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v3.1
   1/*
   2  SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
   3  file Documentation/scsi/st.txt for more information.
   4
   5  History:
   6
   7  OnStream SCSI Tape support (osst) cloned from st.c by
   8  Willem Riede (osst@riede.org) Feb 2000
   9  Fixes ... Kurt Garloff <garloff@suse.de> Mar 2000
  10
  11  Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
  12  Contribution and ideas from several people including (in alphabetical
  13  order) Klaus Ehrenfried, Wolfgang Denk, Steve Hirsch, Andreas Koppenh"ofer,
  14  Michael Leodolter, Eyal Lebedinsky, J"org Weule, and Eric Youngdale.
  15
  16  Copyright 1992 - 2002 Kai Makisara / 2000 - 2006 Willem Riede
  17	 email osst@riede.org
  18
  19  $Header: /cvsroot/osst/Driver/osst.c,v 1.73 2005/01/01 21:13:34 wriede Exp $
  20
  21  Microscopic alterations - Rik Ling, 2000/12/21
  22  Last st.c sync: Tue Oct 15 22:01:04 2002 by makisara
  23  Some small formal changes - aeb, 950809
  24*/
  25
  26static const char * cvsid = "$Id: osst.c,v 1.73 2005/01/01 21:13:34 wriede Exp $";
  27static const char * osst_version = "0.99.4";
  28
  29/* The "failure to reconnect" firmware bug */
  30#define OSST_FW_NEED_POLL_MIN 10601 /*(107A)*/
  31#define OSST_FW_NEED_POLL_MAX 10704 /*(108D)*/
  32#define OSST_FW_NEED_POLL(x,d) ((x) >= OSST_FW_NEED_POLL_MIN && (x) <= OSST_FW_NEED_POLL_MAX && d->host->this_id != 7)
  33
  34#include <linux/module.h>
  35
  36#include <linux/fs.h>
  37#include <linux/kernel.h>
  38#include <linux/sched.h>
  39#include <linux/proc_fs.h>
  40#include <linux/mm.h>
  41#include <linux/slab.h>
  42#include <linux/init.h>
  43#include <linux/string.h>
  44#include <linux/errno.h>
  45#include <linux/mtio.h>
  46#include <linux/ioctl.h>
  47#include <linux/fcntl.h>
  48#include <linux/spinlock.h>
  49#include <linux/vmalloc.h>
  50#include <linux/blkdev.h>
  51#include <linux/moduleparam.h>
  52#include <linux/delay.h>
  53#include <linux/jiffies.h>
  54#include <linux/mutex.h>
  55#include <asm/uaccess.h>
  56#include <asm/dma.h>
  57#include <asm/system.h>
  58
  59/* The driver prints some debugging information on the console if DEBUG
  60   is defined and non-zero. */
  61#define DEBUG 0
  62
  63/* The message level for the debug messages is currently set to KERN_NOTICE
  64   so that people can easily see the messages. Later when the debugging messages
  65   in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
  66#define OSST_DEB_MSG  KERN_NOTICE
  67
  68#include <scsi/scsi.h>
  69#include <scsi/scsi_dbg.h>
  70#include <scsi/scsi_device.h>
  71#include <scsi/scsi_driver.h>
  72#include <scsi/scsi_eh.h>
  73#include <scsi/scsi_host.h>
  74#include <scsi/scsi_ioctl.h>
  75
  76#define ST_KILOBYTE 1024
  77
  78#include "st.h"
  79#include "osst.h"
  80#include "osst_options.h"
  81#include "osst_detect.h"
  82
  83static DEFINE_MUTEX(osst_int_mutex);
  84static int max_dev = 0;
  85static int write_threshold_kbs = 0;
  86static int max_sg_segs = 0;
  87
  88#ifdef MODULE
  89MODULE_AUTHOR("Willem Riede");
  90MODULE_DESCRIPTION("OnStream {DI-|FW-|SC-|USB}{30|50} Tape Driver");
  91MODULE_LICENSE("GPL");
  92MODULE_ALIAS_CHARDEV_MAJOR(OSST_MAJOR);
  93MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
  94
  95module_param(max_dev, int, 0444);
  96MODULE_PARM_DESC(max_dev, "Maximum number of OnStream Tape Drives to attach (4)");
  97
  98module_param(write_threshold_kbs, int, 0644);
  99MODULE_PARM_DESC(write_threshold_kbs, "Asynchronous write threshold (KB; 32)");
 100
 101module_param(max_sg_segs, int, 0644);
 102MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (9)");
 103#else
 104static struct osst_dev_parm {
 105       char   *name;
 106       int    *val;
 107} parms[] __initdata = {
 108       { "max_dev",             &max_dev             },
 109       { "write_threshold_kbs", &write_threshold_kbs },
 110       { "max_sg_segs",         &max_sg_segs         }
 111};
 112#endif
 113
 114/* Some default definitions have been moved to osst_options.h */
 115#define OSST_BUFFER_SIZE (OSST_BUFFER_BLOCKS * ST_KILOBYTE)
 116#define OSST_WRITE_THRESHOLD (OSST_WRITE_THRESHOLD_BLOCKS * ST_KILOBYTE)
 117
 118/* The buffer size should fit into the 24 bits for length in the
 119   6-byte SCSI read and write commands. */
 120#if OSST_BUFFER_SIZE >= (2 << 24 - 1)
 121#error "Buffer size should not exceed (2 << 24 - 1) bytes!"
 122#endif
 123
 124#if DEBUG
 125static int debugging = 1;
 126/* uncomment define below to test error recovery */
 127// #define OSST_INJECT_ERRORS 1 
 128#endif
 129
 130/* Do not retry! The drive firmware already retries when appropriate,
 131   and when it tries to tell us something, we had better listen... */
 132#define MAX_RETRIES 0
 133
 134#define NO_TAPE  NOT_READY
 135
 136#define OSST_WAIT_POSITION_COMPLETE   (HZ > 200 ? HZ / 200 : 1)
 137#define OSST_WAIT_WRITE_COMPLETE      (HZ / 12)
 138#define OSST_WAIT_LONG_WRITE_COMPLETE (HZ / 2)
 139	
 140#define OSST_TIMEOUT (200 * HZ)
 141#define OSST_LONG_TIMEOUT (1800 * HZ)
 142
 143#define TAPE_NR(x) (iminor(x) & ~(-1 << ST_MODE_SHIFT))
 144#define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
 145#define TAPE_REWIND(x) ((iminor(x) & 0x80) == 0)
 146#define TAPE_IS_RAW(x) (TAPE_MODE(x) & (ST_NBR_MODES >> 1))
 147
 148/* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
 149   24 bits) */
 150#define SET_DENS_AND_BLK 0x10001
 151
 152static int osst_buffer_size       = OSST_BUFFER_SIZE;
 153static int osst_write_threshold   = OSST_WRITE_THRESHOLD;
 154static int osst_max_sg_segs       = OSST_MAX_SG;
 155static int osst_max_dev           = OSST_MAX_TAPES;
 156static int osst_nr_dev;
 157
 158static struct osst_tape **os_scsi_tapes = NULL;
 159static DEFINE_RWLOCK(os_scsi_tapes_lock);
 160
 161static int modes_defined = 0;
 162
 163static struct osst_buffer *new_tape_buffer(int, int, int);
 164static int enlarge_buffer(struct osst_buffer *, int);
 165static void normalize_buffer(struct osst_buffer *);
 166static int append_to_buffer(const char __user *, struct osst_buffer *, int);
 167static int from_buffer(struct osst_buffer *, char __user *, int);
 168static int osst_zero_buffer_tail(struct osst_buffer *);
 169static int osst_copy_to_buffer(struct osst_buffer *, unsigned char *);
 170static int osst_copy_from_buffer(struct osst_buffer *, unsigned char *);
 171
 172static int osst_probe(struct device *);
 173static int osst_remove(struct device *);
 174
 175static struct scsi_driver osst_template = {
 176	.owner			= THIS_MODULE,
 177	.gendrv = {
 178		.name		=  "osst",
 
 179		.probe		= osst_probe,
 180		.remove		= osst_remove,
 181	}
 182};
 183
 184static int osst_int_ioctl(struct osst_tape *STp, struct osst_request ** aSRpnt,
 185			    unsigned int cmd_in, unsigned long arg);
 186
 187static int osst_set_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt, int frame, int skip);
 188
 189static int osst_get_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt);
 190
 191static int osst_flush_write_buffer(struct osst_tape *STp, struct osst_request ** aSRpnt);
 192
 193static int osst_write_error_recovery(struct osst_tape * STp, struct osst_request ** aSRpnt, int pending);
 194
 195static inline char *tape_name(struct osst_tape *tape)
 196{
 197	return tape->drive->disk_name;
 198}
 199
 200/* Routines that handle the interaction with mid-layer SCSI routines */
 201
 202
 203/* Normalize Sense */
 204static void osst_analyze_sense(struct osst_request *SRpnt, struct st_cmdstatus *s)
 205{
 206	const u8 *ucp;
 207	const u8 *sense = SRpnt->sense;
 208
 209	s->have_sense = scsi_normalize_sense(SRpnt->sense,
 210				SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
 211	s->flags = 0;
 212
 213	if (s->have_sense) {
 214		s->deferred = 0;
 215		s->remainder_valid =
 216			scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
 217		switch (sense[0] & 0x7f) {
 218		case 0x71:
 219			s->deferred = 1;
 220		case 0x70:
 221			s->fixed_format = 1;
 222			s->flags = sense[2] & 0xe0;
 223			break;
 224		case 0x73:
 225			s->deferred = 1;
 226		case 0x72:
 227			s->fixed_format = 0;
 228			ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
 229			s->flags = ucp ? (ucp[3] & 0xe0) : 0;
 230			break;
 231		}
 232	}
 233}
 234
 235/* Convert the result to success code */
 236static int osst_chk_result(struct osst_tape * STp, struct osst_request * SRpnt)
 237{
 238	char *name = tape_name(STp);
 239	int result = SRpnt->result;
 240	u8 * sense = SRpnt->sense, scode;
 241#if DEBUG
 242	const char *stp;
 243#endif
 244	struct st_cmdstatus *cmdstatp;
 245
 246	if (!result)
 247		return 0;
 248
 249	cmdstatp = &STp->buffer->cmdstat;
 250	osst_analyze_sense(SRpnt, cmdstatp);
 251
 252	if (cmdstatp->have_sense)
 253		scode = STp->buffer->cmdstat.sense_hdr.sense_key;
 254	else
 255		scode = 0;
 256#if DEBUG
 257	if (debugging) {
 258		printk(OSST_DEB_MSG "%s:D: Error: %x, cmd: %x %x %x %x %x %x\n",
 259		   name, result,
 260		   SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
 261		   SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
 262		if (scode) printk(OSST_DEB_MSG "%s:D: Sense: %02x, ASC: %02x, ASCQ: %02x\n",
 263			       	name, scode, sense[12], sense[13]);
 264		if (cmdstatp->have_sense)
 265			__scsi_print_sense("osst ", SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
 
 266	}
 267	else
 268#endif
 269	if (cmdstatp->have_sense && (
 270		 scode != NO_SENSE &&
 271		 scode != RECOVERED_ERROR &&
 272/*      	 scode != UNIT_ATTENTION && */
 273		 scode != BLANK_CHECK &&
 274		 scode != VOLUME_OVERFLOW &&
 275		 SRpnt->cmd[0] != MODE_SENSE &&
 276		 SRpnt->cmd[0] != TEST_UNIT_READY)) { /* Abnormal conditions for tape */
 277		if (cmdstatp->have_sense) {
 278			printk(KERN_WARNING "%s:W: Command with sense data:\n", name);
 279			__scsi_print_sense("osst ", SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
 
 280		}
 281		else {
 282			static	int	notyetprinted = 1;
 283
 284			printk(KERN_WARNING
 285			     "%s:W: Warning %x (driver bt 0x%x, host bt 0x%x).\n",
 286			     name, result, driver_byte(result),
 287			     host_byte(result));
 288			if (notyetprinted) {
 289				notyetprinted = 0;
 290				printk(KERN_INFO
 291					"%s:I: This warning may be caused by your scsi controller,\n", name);
 292				printk(KERN_INFO
 293					"%s:I: it has been reported with some Buslogic cards.\n", name);
 294			}
 295		}
 296	}
 297	STp->pos_unknown |= STp->device->was_reset;
 298
 299	if (cmdstatp->have_sense && scode == RECOVERED_ERROR) {
 300		STp->recover_count++;
 301		STp->recover_erreg++;
 302#if DEBUG
 303		if (debugging) {
 304			if (SRpnt->cmd[0] == READ_6)
 305				stp = "read";
 306			else if (SRpnt->cmd[0] == WRITE_6)
 307				stp = "write";
 308			else
 309				stp = "ioctl";
 310			printk(OSST_DEB_MSG "%s:D: Recovered %s error (%d).\n", name, stp,
 311					     STp->recover_count);
 312		}
 313#endif
 314		if ((sense[2] & 0xe0) == 0)
 315			return 0;
 316	}
 317	return (-EIO);
 318}
 319
 320
 321/* Wakeup from interrupt */
 322static void osst_end_async(struct request *req, int update)
 323{
 
 324	struct osst_request *SRpnt = req->end_io_data;
 325	struct osst_tape *STp = SRpnt->stp;
 326	struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
 327
 328	STp->buffer->cmdstat.midlevel_result = SRpnt->result = req->errors;
 329#if DEBUG
 330	STp->write_pending = 0;
 331#endif
 
 
 332	if (SRpnt->waiting)
 333		complete(SRpnt->waiting);
 334
 335	if (SRpnt->bio) {
 336		kfree(mdata->pages);
 337		blk_rq_unmap_user(SRpnt->bio);
 338	}
 339
 340	__blk_put_request(req->q, req);
 341}
 342
 343/* osst_request memory management */
 344static struct osst_request *osst_allocate_request(void)
 345{
 346	return kzalloc(sizeof(struct osst_request), GFP_KERNEL);
 347}
 348
 349static void osst_release_request(struct osst_request *streq)
 350{
 351	kfree(streq);
 352}
 353
 354static int osst_execute(struct osst_request *SRpnt, const unsigned char *cmd,
 355			int cmd_len, int data_direction, void *buffer, unsigned bufflen,
 356			int use_sg, int timeout, int retries)
 357{
 358	struct request *req;
 
 359	struct page **pages = NULL;
 360	struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
 361
 362	int err = 0;
 363	int write = (data_direction == DMA_TO_DEVICE);
 364
 365	req = blk_get_request(SRpnt->stp->device->request_queue, write, GFP_KERNEL);
 366	if (!req)
 
 367		return DRIVER_ERROR << 24;
 368
 369	req->cmd_type = REQ_TYPE_BLOCK_PC;
 370	req->cmd_flags |= REQ_QUIET;
 371
 372	SRpnt->bio = NULL;
 373
 374	if (use_sg) {
 375		struct scatterlist *sg, *sgl = (struct scatterlist *)buffer;
 376		int i;
 377
 378		pages = kzalloc(use_sg * sizeof(struct page *), GFP_KERNEL);
 379		if (!pages)
 380			goto free_req;
 381
 382		for_each_sg(sgl, sg, use_sg, i)
 383			pages[i] = sg_page(sg);
 384
 385		mdata->null_mapped = 1;
 386
 387		mdata->page_order = get_order(sgl[0].length);
 388		mdata->nr_entries =
 389			DIV_ROUND_UP(bufflen, PAGE_SIZE << mdata->page_order);
 390		mdata->offset = 0;
 391
 392		err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen, GFP_KERNEL);
 393		if (err) {
 394			kfree(pages);
 395			goto free_req;
 396		}
 397		SRpnt->bio = req->bio;
 398		mdata->pages = pages;
 399
 400	} else if (bufflen) {
 401		err = blk_rq_map_kern(req->q, req, buffer, bufflen, GFP_KERNEL);
 402		if (err)
 403			goto free_req;
 404	}
 405
 406	req->cmd_len = cmd_len;
 407	memset(req->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
 408	memcpy(req->cmd, cmd, req->cmd_len);
 409	req->sense = SRpnt->sense;
 410	req->sense_len = 0;
 411	req->timeout = timeout;
 412	req->retries = retries;
 413	req->end_io_data = SRpnt;
 414
 415	blk_execute_rq_nowait(req->q, NULL, req, 1, osst_end_async);
 416	return 0;
 417free_req:
 418	blk_put_request(req);
 419	return DRIVER_ERROR << 24;
 420}
 421
 422/* Do the scsi command. Waits until command performed if do_wait is true.
 423   Otherwise osst_write_behind_check() is used to check that the command
 424   has finished. */
 425static	struct osst_request * osst_do_scsi(struct osst_request *SRpnt, struct osst_tape *STp, 
 426	unsigned char *cmd, int bytes, int direction, int timeout, int retries, int do_wait)
 427{
 428	unsigned char *bp;
 429	unsigned short use_sg;
 430#ifdef OSST_INJECT_ERRORS
 431	static   int   inject = 0;
 432	static   int   repeat = 0;
 433#endif
 434	struct completion *waiting;
 435
 436	/* if async, make sure there's no command outstanding */
 437	if (!do_wait && ((STp->buffer)->last_SRpnt)) {
 438		printk(KERN_ERR "%s: Async command already active.\n",
 439		       tape_name(STp));
 440		if (signal_pending(current))
 441			(STp->buffer)->syscall_result = (-EINTR);
 442		else
 443			(STp->buffer)->syscall_result = (-EBUSY);
 444		return NULL;
 445	}
 446
 447	if (SRpnt == NULL) {
 448		SRpnt = osst_allocate_request();
 449		if (SRpnt == NULL) {
 450			printk(KERN_ERR "%s: Can't allocate SCSI request.\n",
 451				     tape_name(STp));
 452			if (signal_pending(current))
 453				(STp->buffer)->syscall_result = (-EINTR);
 454			else
 455				(STp->buffer)->syscall_result = (-EBUSY);
 456			return NULL;
 457		}
 458		SRpnt->stp = STp;
 459	}
 460
 461	/* If async IO, set last_SRpnt. This ptr tells write_behind_check
 462	   which IO is outstanding. It's nulled out when the IO completes. */
 463	if (!do_wait)
 464		(STp->buffer)->last_SRpnt = SRpnt;
 465
 466	waiting = &STp->wait;
 467	init_completion(waiting);
 468	SRpnt->waiting = waiting;
 469
 470	use_sg = (bytes > STp->buffer->sg[0].length) ? STp->buffer->use_sg : 0;
 471	if (use_sg) {
 472		bp = (char *)&(STp->buffer->sg[0]);
 473		if (STp->buffer->sg_segs < use_sg)
 474			use_sg = STp->buffer->sg_segs;
 475	}
 476	else
 477		bp = (STp->buffer)->b_data;
 478
 479	memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
 480	STp->buffer->cmdstat.have_sense = 0;
 481	STp->buffer->syscall_result = 0;
 482
 483	if (osst_execute(SRpnt, cmd, COMMAND_SIZE(cmd[0]), direction, bp, bytes,
 484			 use_sg, timeout, retries))
 485		/* could not allocate the buffer or request was too large */
 486		(STp->buffer)->syscall_result = (-EBUSY);
 487	else if (do_wait) {
 488		wait_for_completion(waiting);
 489		SRpnt->waiting = NULL;
 490		STp->buffer->syscall_result = osst_chk_result(STp, SRpnt);
 491#ifdef OSST_INJECT_ERRORS
 492		if (STp->buffer->syscall_result == 0 &&
 493		    cmd[0] == READ_6 &&
 494		    cmd[4] && 
 495		    ( (++ inject % 83) == 29  ||
 496		      (STp->first_frame_position == 240 
 497			         /* or STp->read_error_frame to fail again on the block calculated above */ &&
 498				 ++repeat < 3))) {
 499			printk(OSST_DEB_MSG "%s:D: Injecting read error\n", tape_name(STp));
 500			STp->buffer->last_result_fatal = 1;
 501		}
 502#endif
 503	}
 504	return SRpnt;
 505}
 506
 507
 508/* Handle the write-behind checking (downs the semaphore) */
 509static void osst_write_behind_check(struct osst_tape *STp)
 510{
 511	struct osst_buffer * STbuffer;
 512
 513	STbuffer = STp->buffer;
 514
 515#if DEBUG
 516	if (STp->write_pending)
 517		STp->nbr_waits++;
 518	else
 519		STp->nbr_finished++;
 520#endif
 521	wait_for_completion(&(STp->wait));
 522	STp->buffer->last_SRpnt->waiting = NULL;
 523
 524	STp->buffer->syscall_result = osst_chk_result(STp, STp->buffer->last_SRpnt);
 525
 526	if (STp->buffer->syscall_result)
 527		STp->buffer->syscall_result =
 528			osst_write_error_recovery(STp, &(STp->buffer->last_SRpnt), 1);
 529	else
 530		STp->first_frame_position++;
 531
 532	osst_release_request(STp->buffer->last_SRpnt);
 533
 534	if (STbuffer->writing < STbuffer->buffer_bytes)
 535		printk(KERN_WARNING "osst :A: write_behind_check: something left in buffer!\n");
 536
 537	STbuffer->last_SRpnt = NULL;
 538	STbuffer->buffer_bytes -= STbuffer->writing;
 539	STbuffer->writing = 0;
 540
 541	return;
 542}
 543
 544
 545
 546/* Onstream specific Routines */
 547/*
 548 * Initialize the OnStream AUX
 549 */
 550static void osst_init_aux(struct osst_tape * STp, int frame_type, int frame_seq_number,
 551					 int logical_blk_num, int blk_sz, int blk_cnt)
 552{
 553	os_aux_t       *aux = STp->buffer->aux;
 554	os_partition_t *par = &aux->partition;
 555	os_dat_t       *dat = &aux->dat;
 556
 557	if (STp->raw) return;
 558
 559	memset(aux, 0, sizeof(*aux));
 560	aux->format_id = htonl(0);
 561	memcpy(aux->application_sig, "LIN4", 4);
 562	aux->hdwr = htonl(0);
 563	aux->frame_type = frame_type;
 564
 565	switch (frame_type) {
 566	  case	OS_FRAME_TYPE_HEADER:
 567		aux->update_frame_cntr    = htonl(STp->update_frame_cntr);
 568		par->partition_num        = OS_CONFIG_PARTITION;
 569		par->par_desc_ver         = OS_PARTITION_VERSION;
 570		par->wrt_pass_cntr        = htons(0xffff);
 571		/* 0-4 = reserved, 5-9 = header, 2990-2994 = header, 2995-2999 = reserved */
 572		par->first_frame_ppos     = htonl(0);
 573		par->last_frame_ppos      = htonl(0xbb7);
 574		aux->frame_seq_num        = htonl(0);
 575		aux->logical_blk_num_high = htonl(0);
 576		aux->logical_blk_num      = htonl(0);
 577		aux->next_mark_ppos       = htonl(STp->first_mark_ppos);
 578		break;
 579	  case	OS_FRAME_TYPE_DATA:
 580	  case	OS_FRAME_TYPE_MARKER:
 581		dat->dat_sz = 8;
 582		dat->reserved1 = 0;
 583		dat->entry_cnt = 1;
 584		dat->reserved3 = 0;
 585		dat->dat_list[0].blk_sz   = htonl(blk_sz);
 586		dat->dat_list[0].blk_cnt  = htons(blk_cnt);
 587		dat->dat_list[0].flags    = frame_type==OS_FRAME_TYPE_MARKER?
 588							OS_DAT_FLAGS_MARK:OS_DAT_FLAGS_DATA;
 589		dat->dat_list[0].reserved = 0;
 590	  case	OS_FRAME_TYPE_EOD:
 591		aux->update_frame_cntr    = htonl(0);
 592		par->partition_num        = OS_DATA_PARTITION;
 593		par->par_desc_ver         = OS_PARTITION_VERSION;
 594		par->wrt_pass_cntr        = htons(STp->wrt_pass_cntr);
 595		par->first_frame_ppos     = htonl(STp->first_data_ppos);
 596		par->last_frame_ppos      = htonl(STp->capacity);
 597		aux->frame_seq_num        = htonl(frame_seq_number);
 598		aux->logical_blk_num_high = htonl(0);
 599		aux->logical_blk_num      = htonl(logical_blk_num);
 600		break;
 601	  default: ; /* probably FILL */
 602	}
 603	aux->filemark_cnt = htonl(STp->filemark_cnt);
 604	aux->phys_fm = htonl(0xffffffff);
 605	aux->last_mark_ppos = htonl(STp->last_mark_ppos);
 606	aux->last_mark_lbn  = htonl(STp->last_mark_lbn);
 607}
 608
 609/*
 610 * Verify that we have the correct tape frame
 611 */
 612static int osst_verify_frame(struct osst_tape * STp, int frame_seq_number, int quiet)
 613{
 614	char               * name = tape_name(STp);
 615	os_aux_t           * aux  = STp->buffer->aux;
 616	os_partition_t     * par  = &(aux->partition);
 617	struct st_partstat * STps = &(STp->ps[STp->partition]);
 618	int		     blk_cnt, blk_sz, i;
 619
 620	if (STp->raw) {
 621		if (STp->buffer->syscall_result) {
 622			for (i=0; i < STp->buffer->sg_segs; i++)
 623				memset(page_address(sg_page(&STp->buffer->sg[i])),
 624				       0, STp->buffer->sg[i].length);
 625			strcpy(STp->buffer->b_data, "READ ERROR ON FRAME");
 626                } else
 627			STp->buffer->buffer_bytes = OS_FRAME_SIZE;
 628		return 1;
 629	}
 630	if (STp->buffer->syscall_result) {
 631#if DEBUG
 632		printk(OSST_DEB_MSG "%s:D: Skipping frame, read error\n", name);
 633#endif
 634		return 0;
 635	}
 636	if (ntohl(aux->format_id) != 0) {
 637#if DEBUG
 638		printk(OSST_DEB_MSG "%s:D: Skipping frame, format_id %u\n", name, ntohl(aux->format_id));
 639#endif
 640		goto err_out;
 641	}
 642	if (memcmp(aux->application_sig, STp->application_sig, 4) != 0 &&
 643	    (memcmp(aux->application_sig, "LIN3", 4) != 0 || STp->linux_media_version != 4)) {
 644#if DEBUG
 645		printk(OSST_DEB_MSG "%s:D: Skipping frame, incorrect application signature\n", name);
 646#endif
 647		goto err_out;
 648	}
 649	if (par->partition_num != OS_DATA_PARTITION) {
 650		if (!STp->linux_media || STp->linux_media_version != 2) {
 651#if DEBUG
 652			printk(OSST_DEB_MSG "%s:D: Skipping frame, partition num %d\n",
 653					    name, par->partition_num);
 654#endif
 655			goto err_out;
 656		}
 657	}
 658	if (par->par_desc_ver != OS_PARTITION_VERSION) {
 659#if DEBUG
 660		printk(OSST_DEB_MSG "%s:D: Skipping frame, partition version %d\n", name, par->par_desc_ver);
 661#endif
 662		goto err_out;
 663	}
 664	if (ntohs(par->wrt_pass_cntr) != STp->wrt_pass_cntr) {
 665#if DEBUG
 666		printk(OSST_DEB_MSG "%s:D: Skipping frame, wrt_pass_cntr %d (expected %d)\n", 
 667				    name, ntohs(par->wrt_pass_cntr), STp->wrt_pass_cntr);
 668#endif
 669		goto err_out;
 670	}
 671	if (aux->frame_type != OS_FRAME_TYPE_DATA &&
 672	    aux->frame_type != OS_FRAME_TYPE_EOD &&
 673	    aux->frame_type != OS_FRAME_TYPE_MARKER) {
 674		if (!quiet) {
 675#if DEBUG
 676			printk(OSST_DEB_MSG "%s:D: Skipping frame, frame type %x\n", name, aux->frame_type);
 677#endif
 678		}
 679		goto err_out;
 680	}
 681	if (aux->frame_type == OS_FRAME_TYPE_EOD &&
 682	    STp->first_frame_position < STp->eod_frame_ppos) {
 683		printk(KERN_INFO "%s:I: Skipping premature EOD frame %d\n", name,
 684				 STp->first_frame_position);
 685		goto err_out;
 686	}
 687        if (frame_seq_number != -1 && ntohl(aux->frame_seq_num) != frame_seq_number) {
 688		if (!quiet) {
 689#if DEBUG
 690			printk(OSST_DEB_MSG "%s:D: Skipping frame, sequence number %u (expected %d)\n", 
 691					    name, ntohl(aux->frame_seq_num), frame_seq_number);
 692#endif
 693		}
 694		goto err_out;
 695	}
 696	if (aux->frame_type == OS_FRAME_TYPE_MARKER) {
 697		STps->eof = ST_FM_HIT;
 698
 699		i = ntohl(aux->filemark_cnt);
 700		if (STp->header_cache != NULL && i < OS_FM_TAB_MAX && (i > STp->filemark_cnt ||
 701		    STp->first_frame_position - 1 != ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[i]))) {
 702#if DEBUG
 703			printk(OSST_DEB_MSG "%s:D: %s filemark %d at frame pos %d\n", name,
 704				  STp->header_cache->dat_fm_tab.fm_tab_ent[i] == 0?"Learned":"Corrected",
 705				  i, STp->first_frame_position - 1);
 706#endif
 707			STp->header_cache->dat_fm_tab.fm_tab_ent[i] = htonl(STp->first_frame_position - 1);
 708			if (i >= STp->filemark_cnt)
 709				 STp->filemark_cnt = i+1;
 710		}
 711	}
 712	if (aux->frame_type == OS_FRAME_TYPE_EOD) {
 713		STps->eof = ST_EOD_1;
 714		STp->frame_in_buffer = 1;
 715	}
 716	if (aux->frame_type == OS_FRAME_TYPE_DATA) {
 717                blk_cnt = ntohs(aux->dat.dat_list[0].blk_cnt);
 718		blk_sz  = ntohl(aux->dat.dat_list[0].blk_sz);
 719		STp->buffer->buffer_bytes = blk_cnt * blk_sz;
 720		STp->buffer->read_pointer = 0;
 721		STp->frame_in_buffer = 1;
 722
 723		/* See what block size was used to write file */
 724		if (STp->block_size != blk_sz && blk_sz > 0) {
 725			printk(KERN_INFO
 726	    	"%s:I: File was written with block size %d%c, currently %d%c, adjusted to match.\n",
 727       				name, blk_sz<1024?blk_sz:blk_sz/1024,blk_sz<1024?'b':'k',
 728				STp->block_size<1024?STp->block_size:STp->block_size/1024,
 729				STp->block_size<1024?'b':'k');
 730			STp->block_size            = blk_sz;
 731			STp->buffer->buffer_blocks = OS_DATA_SIZE / blk_sz;
 732		}
 733		STps->eof = ST_NOEOF;
 734	}
 735        STp->frame_seq_number = ntohl(aux->frame_seq_num);
 736	STp->logical_blk_num  = ntohl(aux->logical_blk_num);
 737	return 1;
 738
 739err_out:
 740	if (STp->read_error_frame == 0)
 741		STp->read_error_frame = STp->first_frame_position - 1;
 742	return 0;
 743}
 744
 745/*
 746 * Wait for the unit to become Ready
 747 */
 748static int osst_wait_ready(struct osst_tape * STp, struct osst_request ** aSRpnt,
 749				 unsigned timeout, int initial_delay)
 750{
 751	unsigned char		cmd[MAX_COMMAND_SIZE];
 752	struct osst_request   * SRpnt;
 753	unsigned long		startwait = jiffies;
 754#if DEBUG
 755	int			dbg  = debugging;
 756	char    	      * name = tape_name(STp);
 757
 758	printk(OSST_DEB_MSG "%s:D: Reached onstream wait ready\n", name);
 759#endif
 760
 761	if (initial_delay > 0)
 762		msleep(jiffies_to_msecs(initial_delay));
 763
 764	memset(cmd, 0, MAX_COMMAND_SIZE);
 765	cmd[0] = TEST_UNIT_READY;
 766
 767	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 768	*aSRpnt = SRpnt;
 769	if (!SRpnt) return (-EBUSY);
 770
 771	while ( STp->buffer->syscall_result && time_before(jiffies, startwait + timeout*HZ) &&
 772	       (( SRpnt->sense[2]  == 2 && SRpnt->sense[12] == 4    &&
 773		 (SRpnt->sense[13] == 1 || SRpnt->sense[13] == 8)    ) ||
 774		( SRpnt->sense[2]  == 6 && SRpnt->sense[12] == 0x28 &&
 775		  SRpnt->sense[13] == 0                                        )  )) {
 776#if DEBUG
 777	    if (debugging) {
 778		printk(OSST_DEB_MSG "%s:D: Sleeping in onstream wait ready\n", name);
 779		printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
 780		debugging = 0;
 781	    }
 782#endif
 783	    msleep(100);
 784
 785	    memset(cmd, 0, MAX_COMMAND_SIZE);
 786	    cmd[0] = TEST_UNIT_READY;
 787
 788	    SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 789	}
 790	*aSRpnt = SRpnt;
 791#if DEBUG
 792	debugging = dbg;
 793#endif
 794	if ( STp->buffer->syscall_result &&
 795	     osst_write_error_recovery(STp, aSRpnt, 0) ) {
 796#if DEBUG
 797	    printk(OSST_DEB_MSG "%s:D: Abnormal exit from onstream wait ready\n", name);
 798	    printk(OSST_DEB_MSG "%s:D: Result = %d, Sense: 0=%02x, 2=%02x, 12=%02x, 13=%02x\n", name,
 799			STp->buffer->syscall_result, SRpnt->sense[0], SRpnt->sense[2],
 800			SRpnt->sense[12], SRpnt->sense[13]);
 801#endif
 802	    return (-EIO);
 803	}
 804#if DEBUG
 805	printk(OSST_DEB_MSG "%s:D: Normal exit from onstream wait ready\n", name);
 806#endif
 807	return 0;
 808}
 809
 810/*
 811 * Wait for a tape to be inserted in the unit
 812 */
 813static int osst_wait_for_medium(struct osst_tape * STp, struct osst_request ** aSRpnt, unsigned timeout)
 814{
 815	unsigned char		cmd[MAX_COMMAND_SIZE];
 816	struct osst_request   * SRpnt;
 817	unsigned long		startwait = jiffies;
 818#if DEBUG
 819	int			dbg = debugging;
 820	char    	      * name = tape_name(STp);
 821
 822	printk(OSST_DEB_MSG "%s:D: Reached onstream wait for medium\n", name);
 823#endif
 824
 825	memset(cmd, 0, MAX_COMMAND_SIZE);
 826	cmd[0] = TEST_UNIT_READY;
 827
 828	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 829	*aSRpnt = SRpnt;
 830	if (!SRpnt) return (-EBUSY);
 831
 832	while ( STp->buffer->syscall_result && time_before(jiffies, startwait + timeout*HZ) &&
 833		SRpnt->sense[2] == 2 && SRpnt->sense[12] == 0x3a && SRpnt->sense[13] == 0  ) {
 834#if DEBUG
 835	    if (debugging) {
 836		printk(OSST_DEB_MSG "%s:D: Sleeping in onstream wait medium\n", name);
 837		printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
 838		debugging = 0;
 839	    }
 840#endif
 841	    msleep(100);
 842
 843	    memset(cmd, 0, MAX_COMMAND_SIZE);
 844	    cmd[0] = TEST_UNIT_READY;
 845
 846	    SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 847	}
 848	*aSRpnt = SRpnt;
 849#if DEBUG
 850	debugging = dbg;
 851#endif
 852	if ( STp->buffer->syscall_result     && SRpnt->sense[2]  != 2 &&
 853	     SRpnt->sense[12] != 4 && SRpnt->sense[13] == 1) {
 854#if DEBUG
 855	    printk(OSST_DEB_MSG "%s:D: Abnormal exit from onstream wait medium\n", name);
 856	    printk(OSST_DEB_MSG "%s:D: Result = %d, Sense: 0=%02x, 2=%02x, 12=%02x, 13=%02x\n", name,
 857			STp->buffer->syscall_result, SRpnt->sense[0], SRpnt->sense[2],
 858			SRpnt->sense[12], SRpnt->sense[13]);
 859#endif
 860	    return 0;
 861	}
 862#if DEBUG
 863	printk(OSST_DEB_MSG "%s:D: Normal exit from onstream wait medium\n", name);
 864#endif
 865	return 1;
 866}
 867
 868static int osst_position_tape_and_confirm(struct osst_tape * STp, struct osst_request ** aSRpnt, int frame)
 869{
 870	int	retval;
 871
 872	osst_wait_ready(STp, aSRpnt, 15 * 60, 0);			/* TODO - can this catch a write error? */
 873	retval = osst_set_frame_position(STp, aSRpnt, frame, 0);
 874	if (retval) return (retval);
 875	osst_wait_ready(STp, aSRpnt, 15 * 60, OSST_WAIT_POSITION_COMPLETE);
 876	return (osst_get_frame_position(STp, aSRpnt));
 877}
 878
 879/*
 880 * Wait for write(s) to complete
 881 */
 882static int osst_flush_drive_buffer(struct osst_tape * STp, struct osst_request ** aSRpnt)
 883{
 884	unsigned char		cmd[MAX_COMMAND_SIZE];
 885	struct osst_request   * SRpnt;
 886	int			result = 0;
 887	int			delay  = OSST_WAIT_WRITE_COMPLETE;
 888#if DEBUG
 889	char		      * name = tape_name(STp);
 890
 891	printk(OSST_DEB_MSG "%s:D: Reached onstream flush drive buffer (write filemark)\n", name);
 892#endif
 893
 894	memset(cmd, 0, MAX_COMMAND_SIZE);
 895	cmd[0] = WRITE_FILEMARKS;
 896	cmd[1] = 1;
 897
 898	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 899	*aSRpnt = SRpnt;
 900	if (!SRpnt) return (-EBUSY);
 901	if (STp->buffer->syscall_result) {
 902		if ((SRpnt->sense[2] & 0x0f) == 2 && SRpnt->sense[12] == 4) {
 903			if (SRpnt->sense[13] == 8) {
 904				delay = OSST_WAIT_LONG_WRITE_COMPLETE;
 905			}
 906		} else
 907			result = osst_write_error_recovery(STp, aSRpnt, 0);
 908	}
 909	result |= osst_wait_ready(STp, aSRpnt, 5 * 60, delay);
 910	STp->ps[STp->partition].rw = OS_WRITING_COMPLETE;
 911
 912	return (result);
 913}
 914
 915#define OSST_POLL_PER_SEC 10
 916static int osst_wait_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int curr, int minlast, int to)
 917{
 918	unsigned long	startwait = jiffies;
 919	char	      * name      = tape_name(STp);
 920#if DEBUG
 921	char	   notyetprinted  = 1;
 922#endif
 923	if (minlast >= 0 && STp->ps[STp->partition].rw != ST_READING)
 924		printk(KERN_ERR "%s:A: Waiting for frame without having initialized read!\n", name);
 925
 926	while (time_before (jiffies, startwait + to*HZ))
 927	{ 
 928		int result;
 929		result = osst_get_frame_position(STp, aSRpnt);
 930		if (result == -EIO)
 931			if ((result = osst_write_error_recovery(STp, aSRpnt, 0)) == 0)
 932				return 0;	/* successful recovery leaves drive ready for frame */
 933		if (result < 0) break;
 934		if (STp->first_frame_position == curr &&
 935		    ((minlast < 0 &&
 936		      (signed)STp->last_frame_position > (signed)curr + minlast) ||
 937		     (minlast >= 0 && STp->cur_frames > minlast)
 938		    ) && result >= 0)
 939		{
 940#if DEBUG			
 941			if (debugging || time_after_eq(jiffies, startwait + 2*HZ/OSST_POLL_PER_SEC))
 942				printk (OSST_DEB_MSG
 943					"%s:D: Succ wait f fr %i (>%i): %i-%i %i (%i): %3li.%li s\n",
 944					name, curr, curr+minlast, STp->first_frame_position,
 945					STp->last_frame_position, STp->cur_frames,
 946					result, (jiffies-startwait)/HZ, 
 947					(((jiffies-startwait)%HZ)*10)/HZ);
 948#endif
 949			return 0;
 950		}
 951#if DEBUG
 952		if (time_after_eq(jiffies, startwait + 2*HZ/OSST_POLL_PER_SEC) && notyetprinted)
 953		{
 954			printk (OSST_DEB_MSG "%s:D: Wait for frame %i (>%i): %i-%i %i (%i)\n",
 955				name, curr, curr+minlast, STp->first_frame_position,
 956				STp->last_frame_position, STp->cur_frames, result);
 957			notyetprinted--;
 958		}
 959#endif
 960		msleep(1000 / OSST_POLL_PER_SEC);
 961	}
 962#if DEBUG
 963	printk (OSST_DEB_MSG "%s:D: Fail wait f fr %i (>%i): %i-%i %i: %3li.%li s\n",
 964		name, curr, curr+minlast, STp->first_frame_position,
 965		STp->last_frame_position, STp->cur_frames,
 966		(jiffies-startwait)/HZ, (((jiffies-startwait)%HZ)*10)/HZ);
 967#endif	
 968	return -EBUSY;
 969}
 970
 971static int osst_recover_wait_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int writing)
 972{
 973	struct osst_request   * SRpnt;
 974	unsigned char		cmd[MAX_COMMAND_SIZE];
 975	unsigned long   	startwait = jiffies;
 976	int			retval    = 1;
 977        char		      * name      = tape_name(STp);
 978                                                                                                                                
 979	if (writing) {
 980		char	mybuf[24];
 981		char  * olddata = STp->buffer->b_data;
 982		int	oldsize = STp->buffer->buffer_size;
 983
 984		/* write zero fm then read pos - if shows write error, try to recover - if no progress, wait */
 985
 986		memset(cmd, 0, MAX_COMMAND_SIZE);
 987		cmd[0] = WRITE_FILEMARKS;
 988		cmd[1] = 1;
 989		SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout,
 990								MAX_RETRIES, 1);
 991
 992		while (retval && time_before (jiffies, startwait + 5*60*HZ)) {
 993
 994			if (STp->buffer->syscall_result && (SRpnt->sense[2] & 0x0f) != 2) {
 995
 996				/* some failure - not just not-ready */
 997				retval = osst_write_error_recovery(STp, aSRpnt, 0);
 998				break;
 999			}
1000			schedule_timeout_interruptible(HZ / OSST_POLL_PER_SEC);
1001
1002			STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
1003			memset(cmd, 0, MAX_COMMAND_SIZE);
1004			cmd[0] = READ_POSITION;
1005
1006			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 20, DMA_FROM_DEVICE, STp->timeout,
1007										MAX_RETRIES, 1);
1008
1009			retval = ( STp->buffer->syscall_result || (STp->buffer)->b_data[15] > 25 );
1010			STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
1011		}
1012		if (retval)
1013			printk(KERN_ERR "%s:E: Device did not succeed to write buffered data\n", name);
1014	} else
1015		/* TODO - figure out which error conditions can be handled */
1016		if (STp->buffer->syscall_result)
1017			printk(KERN_WARNING
1018				"%s:W: Recover_wait_frame(read) cannot handle %02x:%02x:%02x\n", name,
1019					(*aSRpnt)->sense[ 2] & 0x0f,
1020					(*aSRpnt)->sense[12],
1021					(*aSRpnt)->sense[13]);
1022
1023	return retval;
1024}
1025
1026/*
1027 * Read the next OnStream tape frame at the current location
1028 */
1029static int osst_read_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int timeout)
1030{
1031	unsigned char		cmd[MAX_COMMAND_SIZE];
1032	struct osst_request   * SRpnt;
1033	int			retval = 0;
1034#if DEBUG
1035	os_aux_t	      * aux    = STp->buffer->aux;
1036	char		      * name   = tape_name(STp);
1037#endif
1038
1039	if (STp->poll)
1040		if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, 0, timeout))
1041			retval = osst_recover_wait_frame(STp, aSRpnt, 0);
1042
1043	memset(cmd, 0, MAX_COMMAND_SIZE);
1044	cmd[0] = READ_6;
1045	cmd[1] = 1;
1046	cmd[4] = 1;
1047
1048#if DEBUG
1049	if (debugging)
1050		printk(OSST_DEB_MSG "%s:D: Reading frame from OnStream tape\n", name);
1051#endif
1052	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_FROM_DEVICE,
1053				      STp->timeout, MAX_RETRIES, 1);
1054	*aSRpnt = SRpnt;
1055	if (!SRpnt)
1056		return (-EBUSY);
1057
1058	if ((STp->buffer)->syscall_result) {
1059	    retval = 1;
1060	    if (STp->read_error_frame == 0) {
1061		STp->read_error_frame = STp->first_frame_position;
1062#if DEBUG
1063		printk(OSST_DEB_MSG "%s:D: Recording read error at %d\n", name, STp->read_error_frame);
1064#endif
1065	    }
1066#if DEBUG
1067	    if (debugging)
1068		printk(OSST_DEB_MSG "%s:D: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1069		   name,
1070		   SRpnt->sense[0], SRpnt->sense[1],
1071		   SRpnt->sense[2], SRpnt->sense[3],
1072		   SRpnt->sense[4], SRpnt->sense[5],
1073		   SRpnt->sense[6], SRpnt->sense[7]);
1074#endif
1075	}
1076	else
1077	    STp->first_frame_position++;
1078#if DEBUG
1079	if (debugging) {
1080	   char sig[8]; int i;
1081	   for (i=0;i<4;i++)
1082		   sig[i] = aux->application_sig[i]<32?'^':aux->application_sig[i];
1083	   sig[4] = '\0';
1084	   printk(OSST_DEB_MSG 
1085		"%s:D: AUX: %s UpdFrCt#%d Wpass#%d %s FrSeq#%d LogBlk#%d Qty=%d Sz=%d\n", name, sig,
1086			ntohl(aux->update_frame_cntr), ntohs(aux->partition.wrt_pass_cntr),
1087			aux->frame_type==1?"EOD":aux->frame_type==2?"MARK":
1088			aux->frame_type==8?"HEADR":aux->frame_type==0x80?"DATA":"FILL", 
1089			ntohl(aux->frame_seq_num), ntohl(aux->logical_blk_num),
1090			ntohs(aux->dat.dat_list[0].blk_cnt), ntohl(aux->dat.dat_list[0].blk_sz) );
1091	   if (aux->frame_type==2)
1092		printk(OSST_DEB_MSG "%s:D: mark_cnt=%d, last_mark_ppos=%d, last_mark_lbn=%d\n", name,
1093			ntohl(aux->filemark_cnt), ntohl(aux->last_mark_ppos), ntohl(aux->last_mark_lbn));
1094	   printk(OSST_DEB_MSG "%s:D: Exit read frame from OnStream tape with code %d\n", name, retval);
1095	}
1096#endif
1097	return (retval);
1098}
1099
1100static int osst_initiate_read(struct osst_tape * STp, struct osst_request ** aSRpnt)
1101{
1102	struct st_partstat    * STps   = &(STp->ps[STp->partition]);
1103	struct osst_request   * SRpnt  ;
1104	unsigned char		cmd[MAX_COMMAND_SIZE];
1105	int			retval = 0;
1106	char		      * name   = tape_name(STp);
1107
1108	if (STps->rw != ST_READING) {         /* Initialize read operation */
1109		if (STps->rw == ST_WRITING || STp->dirty) {
1110			STp->write_type = OS_WRITE_DATA;
1111                        osst_flush_write_buffer(STp, aSRpnt);
1112			osst_flush_drive_buffer(STp, aSRpnt);
1113		}
1114		STps->rw = ST_READING;
1115		STp->frame_in_buffer = 0;
1116
1117		/*
1118		 *      Issue a read 0 command to get the OnStream drive
1119                 *      read frames into its buffer.
1120		 */
1121		memset(cmd, 0, MAX_COMMAND_SIZE);
1122		cmd[0] = READ_6;
1123		cmd[1] = 1;
1124
1125#if DEBUG
1126		printk(OSST_DEB_MSG "%s:D: Start Read Ahead on OnStream tape\n", name);
1127#endif
1128		SRpnt   = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
1129		*aSRpnt = SRpnt;
1130		if ((retval = STp->buffer->syscall_result))
1131			printk(KERN_WARNING "%s:W: Error starting read ahead\n", name);
1132	}
1133
1134	return retval;
1135}
1136
1137static int osst_get_logical_frame(struct osst_tape * STp, struct osst_request ** aSRpnt,
1138						int frame_seq_number, int quiet)
1139{
1140	struct st_partstat * STps  = &(STp->ps[STp->partition]);
1141	char		   * name  = tape_name(STp);
1142	int		     cnt   = 0,
1143			     bad   = 0,
1144			     past  = 0,
1145			     x,
1146			     position;
1147
1148	/*
1149	 * If we want just any frame (-1) and there is a frame in the buffer, return it
1150	 */
1151	if (frame_seq_number == -1 && STp->frame_in_buffer) {
1152#if DEBUG
1153		printk(OSST_DEB_MSG "%s:D: Frame %d still in buffer\n", name, STp->frame_seq_number);
1154#endif
1155		return (STps->eof);
1156	}
1157	/*
1158         * Search and wait for the next logical tape frame
1159	 */
1160	while (1) {
1161		if (cnt++ > 400) {
1162                        printk(KERN_ERR "%s:E: Couldn't find logical frame %d, aborting\n",
1163					    name, frame_seq_number);
1164			if (STp->read_error_frame) {
1165				osst_set_frame_position(STp, aSRpnt, STp->read_error_frame, 0);
1166#if DEBUG
1167                        	printk(OSST_DEB_MSG "%s:D: Repositioning tape to bad frame %d\n",
1168						    name, STp->read_error_frame);
1169#endif
1170				STp->read_error_frame = 0;
1171				STp->abort_count++;
1172			}
1173			return (-EIO);
1174		}
1175#if DEBUG
1176		if (debugging)
1177			printk(OSST_DEB_MSG "%s:D: Looking for frame %d, attempt %d\n",
1178					  name, frame_seq_number, cnt);
1179#endif
1180		if ( osst_initiate_read(STp, aSRpnt)
1181                || ( (!STp->frame_in_buffer) && osst_read_frame(STp, aSRpnt, 30) ) ) {
1182			if (STp->raw)
1183				return (-EIO);
1184			position = osst_get_frame_position(STp, aSRpnt);
1185			if (position >= 0xbae && position < 0xbb8)
1186				position = 0xbb8;
1187			else if (position > STp->eod_frame_ppos || ++bad == 10) {
1188				position = STp->read_error_frame - 1;
1189				bad = 0;
1190			}
1191			else {
1192				position += 29;
1193				cnt      += 19;
1194			}
1195#if DEBUG
1196			printk(OSST_DEB_MSG "%s:D: Bad frame detected, positioning tape to block %d\n",
1197					 name, position);
1198#endif
1199			osst_set_frame_position(STp, aSRpnt, position, 0);
1200			continue;
1201		}
1202		if (osst_verify_frame(STp, frame_seq_number, quiet))
1203			break;
1204		if (osst_verify_frame(STp, -1, quiet)) {
1205			x = ntohl(STp->buffer->aux->frame_seq_num);
1206			if (STp->fast_open) {
1207				printk(KERN_WARNING
1208				       "%s:W: Found logical frame %d instead of %d after fast open\n",
1209				       name, x, frame_seq_number);
1210				STp->header_ok = 0;
1211				STp->read_error_frame = 0;
1212				return (-EIO);
1213			}
1214			if (x > frame_seq_number) {
1215				if (++past > 3) {
1216					/* positioning backwards did not bring us to the desired frame */
1217					position = STp->read_error_frame - 1;
1218				}
1219				else {
1220			        	position = osst_get_frame_position(STp, aSRpnt)
1221					         + frame_seq_number - x - 1;
1222
1223					if (STp->first_frame_position >= 3000 && position < 3000)
1224						position -= 10;
1225				}
1226#if DEBUG
1227                                printk(OSST_DEB_MSG
1228				       "%s:D: Found logical frame %d while looking for %d: back up %d\n",
1229						name, x, frame_seq_number,
1230					       	STp->first_frame_position - position);
1231#endif
1232                        	osst_set_frame_position(STp, aSRpnt, position, 0);
1233				cnt += 10;
1234			}
1235			else
1236				past = 0;
1237		}
1238		if (osst_get_frame_position(STp, aSRpnt) == 0xbaf) {
1239#if DEBUG
1240			printk(OSST_DEB_MSG "%s:D: Skipping config partition\n", name);
1241#endif
1242			osst_set_frame_position(STp, aSRpnt, 0xbb8, 0);
1243			cnt--;
1244		}
1245		STp->frame_in_buffer = 0;
1246	}
1247	if (cnt > 1) {
1248		STp->recover_count++;
1249		STp->recover_erreg++;
1250		printk(KERN_WARNING "%s:I: Don't worry, Read error at position %d recovered\n", 
1251					name, STp->read_error_frame);
1252 	}
1253	STp->read_count++;
1254
1255#if DEBUG
1256	if (debugging || STps->eof)
1257		printk(OSST_DEB_MSG
1258			"%s:D: Exit get logical frame (%d=>%d) from OnStream tape with code %d\n",
1259			name, frame_seq_number, STp->frame_seq_number, STps->eof);
1260#endif
1261	STp->fast_open = 0;
1262	STp->read_error_frame = 0;
1263	return (STps->eof);
1264}
1265
1266static int osst_seek_logical_blk(struct osst_tape * STp, struct osst_request ** aSRpnt, int logical_blk_num)
1267{
1268        struct st_partstat * STps = &(STp->ps[STp->partition]);
1269	char		   * name = tape_name(STp);
1270	int	retries    = 0;
1271	int	frame_seq_estimate, ppos_estimate, move;
1272	
1273	if (logical_blk_num < 0) logical_blk_num = 0;
1274#if DEBUG
1275	printk(OSST_DEB_MSG "%s:D: Seeking logical block %d (now at %d, size %d%c)\n",
1276				name, logical_blk_num, STp->logical_blk_num, 
1277				STp->block_size<1024?STp->block_size:STp->block_size/1024,
1278				STp->block_size<1024?'b':'k');
1279#endif
1280	/* Do we know where we are? */
1281	if (STps->drv_block >= 0) {
1282		move                = logical_blk_num - STp->logical_blk_num;
1283		if (move < 0) move -= (OS_DATA_SIZE / STp->block_size) - 1;
1284		move               /= (OS_DATA_SIZE / STp->block_size);
1285		frame_seq_estimate  = STp->frame_seq_number + move;
1286	} else
1287		frame_seq_estimate  = logical_blk_num * STp->block_size / OS_DATA_SIZE;
1288
1289	if (frame_seq_estimate < 2980) ppos_estimate = frame_seq_estimate + 10;
1290	else			       ppos_estimate = frame_seq_estimate + 20;
1291	while (++retries < 10) {
1292	   if (ppos_estimate > STp->eod_frame_ppos-2) {
1293	       frame_seq_estimate += STp->eod_frame_ppos - 2 - ppos_estimate;
1294	       ppos_estimate       = STp->eod_frame_ppos - 2;
1295	   }
1296	   if (frame_seq_estimate < 0) {
1297	       frame_seq_estimate = 0;
1298	       ppos_estimate      = 10;
1299	   }
1300	   osst_set_frame_position(STp, aSRpnt, ppos_estimate, 0);
1301	   if (osst_get_logical_frame(STp, aSRpnt, frame_seq_estimate, 1) >= 0) {
1302	      /* we've located the estimated frame, now does it have our block? */
1303	      if (logical_blk_num <  STp->logical_blk_num ||
1304	          logical_blk_num >= STp->logical_blk_num + ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt)) {
1305		 if (STps->eof == ST_FM_HIT)
1306		    move = logical_blk_num < STp->logical_blk_num? -2 : 1;
1307		 else {
1308		    move                = logical_blk_num - STp->logical_blk_num;
1309		    if (move < 0) move -= (OS_DATA_SIZE / STp->block_size) - 1;
1310		    move               /= (OS_DATA_SIZE / STp->block_size);
1311		 }
1312		 if (!move) move = logical_blk_num > STp->logical_blk_num ? 1 : -1;
1313#if DEBUG
1314		 printk(OSST_DEB_MSG
1315			"%s:D: Seek retry %d at ppos %d fsq %d (est %d) lbn %d (need %d) move %d\n",
1316				name, retries, ppos_estimate, STp->frame_seq_number, frame_seq_estimate, 
1317				STp->logical_blk_num, logical_blk_num, move);
1318#endif
1319		 frame_seq_estimate += move;
1320		 ppos_estimate      += move;
1321		 continue;
1322	      } else {
1323		 STp->buffer->read_pointer  = (logical_blk_num - STp->logical_blk_num) * STp->block_size;
1324		 STp->buffer->buffer_bytes -= STp->buffer->read_pointer;
1325		 STp->logical_blk_num       =  logical_blk_num;
1326#if DEBUG
1327		 printk(OSST_DEB_MSG 
1328			"%s:D: Seek success at ppos %d fsq %d in_buf %d, bytes %d, ptr %d*%d\n",
1329				name, ppos_estimate, STp->frame_seq_number, STp->frame_in_buffer, 
1330				STp->buffer->buffer_bytes, STp->buffer->read_pointer / STp->block_size, 
1331				STp->block_size);
1332#endif
1333		 STps->drv_file = ntohl(STp->buffer->aux->filemark_cnt);
1334		 if (STps->eof == ST_FM_HIT) {
1335		     STps->drv_file++;
1336		     STps->drv_block = 0;
1337		 } else {
1338		     STps->drv_block = ntohl(STp->buffer->aux->last_mark_lbn)?
1339					  STp->logical_blk_num -
1340					     (STps->drv_file ? ntohl(STp->buffer->aux->last_mark_lbn) + 1 : 0):
1341					-1;
1342		 }
1343		 STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_NOEOF;
1344		 return 0;
1345	      }
1346	   }
1347	   if (osst_get_logical_frame(STp, aSRpnt, -1, 1) < 0)
1348	      goto error;
1349	   /* we are not yet at the estimated frame, adjust our estimate of its physical position */
1350#if DEBUG
1351	   printk(OSST_DEB_MSG "%s:D: Seek retry %d at ppos %d fsq %d (est %d) lbn %d (need %d)\n", 
1352			   name, retries, ppos_estimate, STp->frame_seq_number, frame_seq_estimate, 
1353			   STp->logical_blk_num, logical_blk_num);
1354#endif
1355	   if (frame_seq_estimate != STp->frame_seq_number)
1356	      ppos_estimate += frame_seq_estimate - STp->frame_seq_number;
1357	   else
1358	      break;
1359	}
1360error:
1361	printk(KERN_ERR "%s:E: Couldn't seek to logical block %d (at %d), %d retries\n", 
1362			    name, logical_blk_num, STp->logical_blk_num, retries);
1363	return (-EIO);
1364}
1365
1366/* The values below are based on the OnStream frame payload size of 32K == 2**15,
1367 * that is, OSST_FRAME_SHIFT + OSST_SECTOR_SHIFT must be 15. With a minimum block
1368 * size of 512 bytes, we need to be able to resolve 32K/512 == 64 == 2**6 positions
1369 * inside each frame. Finally, OSST_SECTOR_MASK == 2**OSST_FRAME_SHIFT - 1.
1370 */
1371#define OSST_FRAME_SHIFT  6
1372#define OSST_SECTOR_SHIFT 9
1373#define OSST_SECTOR_MASK  0x03F
1374
1375static int osst_get_sector(struct osst_tape * STp, struct osst_request ** aSRpnt)
1376{
1377	int	sector;
1378#if DEBUG
1379	char  * name = tape_name(STp);
1380	
1381	printk(OSST_DEB_MSG 
1382		"%s:D: Positioned at ppos %d, frame %d, lbn %d, file %d, blk %d, %cptr %d, eof %d\n",
1383		name, STp->first_frame_position, STp->frame_seq_number, STp->logical_blk_num,
1384		STp->ps[STp->partition].drv_file, STp->ps[STp->partition].drv_block, 
1385		STp->ps[STp->partition].rw == ST_WRITING?'w':'r',
1386		STp->ps[STp->partition].rw == ST_WRITING?STp->buffer->buffer_bytes:
1387		STp->buffer->read_pointer, STp->ps[STp->partition].eof);
1388#endif
1389	/* do we know where we are inside a file? */
1390	if (STp->ps[STp->partition].drv_block >= 0) {
1391		sector = (STp->frame_in_buffer ? STp->first_frame_position-1 :
1392				STp->first_frame_position) << OSST_FRAME_SHIFT;
1393		if (STp->ps[STp->partition].rw == ST_WRITING)
1394		       	sector |= (STp->buffer->buffer_bytes >> OSST_SECTOR_SHIFT) & OSST_SECTOR_MASK;
1395		else
1396	       		sector |= (STp->buffer->read_pointer >> OSST_SECTOR_SHIFT) & OSST_SECTOR_MASK;
1397	} else {
1398		sector = osst_get_frame_position(STp, aSRpnt);
1399		if (sector > 0)
1400			sector <<= OSST_FRAME_SHIFT;
1401	}
1402	return sector;
1403}
1404
1405static int osst_seek_sector(struct osst_tape * STp, struct osst_request ** aSRpnt, int sector)
1406{
1407        struct st_partstat * STps   = &(STp->ps[STp->partition]);
1408	int		     frame  = sector >> OSST_FRAME_SHIFT,
1409			     offset = (sector & OSST_SECTOR_MASK) << OSST_SECTOR_SHIFT, 
1410			     r;
1411#if DEBUG
1412	char          * name = tape_name(STp);
1413
1414	printk(OSST_DEB_MSG "%s:D: Seeking sector %d in frame %d at offset %d\n",
1415				name, sector, frame, offset);
1416#endif
1417	if (frame < 0 || frame >= STp->capacity) return (-ENXIO);
1418
1419	if (frame <= STp->first_data_ppos) {
1420		STp->frame_seq_number = STp->logical_blk_num = STps->drv_file = STps->drv_block = 0;
1421		return (osst_set_frame_position(STp, aSRpnt, frame, 0));
1422	}
1423	r = osst_set_frame_position(STp, aSRpnt, offset?frame:frame-1, 0);
1424	if (r < 0) return r;
1425
1426	r = osst_get_logical_frame(STp, aSRpnt, -1, 1);
1427	if (r < 0) return r;
1428
1429	if (osst_get_frame_position(STp, aSRpnt) != (offset?frame+1:frame)) return (-EIO);
1430
1431	if (offset) {
1432		STp->logical_blk_num      += offset / STp->block_size;
1433		STp->buffer->read_pointer  = offset;
1434		STp->buffer->buffer_bytes -= offset;
1435	} else {
1436		STp->frame_seq_number++;
1437		STp->frame_in_buffer       = 0;
1438		STp->logical_blk_num      += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1439		STp->buffer->buffer_bytes  = STp->buffer->read_pointer = 0;
1440	}
1441	STps->drv_file = ntohl(STp->buffer->aux->filemark_cnt);
1442	if (STps->eof == ST_FM_HIT) {
1443		STps->drv_file++;
1444		STps->drv_block = 0;
1445	} else {
1446		STps->drv_block = ntohl(STp->buffer->aux->last_mark_lbn)?
1447				    STp->logical_blk_num -
1448					(STps->drv_file ? ntohl(STp->buffer->aux->last_mark_lbn) + 1 : 0):
1449				  -1;
1450	}
1451	STps->eof       = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_NOEOF;
1452#if DEBUG
1453	printk(OSST_DEB_MSG 
1454		"%s:D: Now positioned at ppos %d, frame %d, lbn %d, file %d, blk %d, rptr %d, eof %d\n",
1455		name, STp->first_frame_position, STp->frame_seq_number, STp->logical_blk_num,
1456		STps->drv_file, STps->drv_block, STp->buffer->read_pointer, STps->eof);
1457#endif
1458	return 0;
1459}
1460
1461/*
1462 * Read back the drive's internal buffer contents, as a part
1463 * of the write error recovery mechanism for old OnStream
1464 * firmware revisions.
1465 * Precondition for this function to work: all frames in the
1466 * drive's buffer must be of one type (DATA, MARK or EOD)!
1467 */
1468static int osst_read_back_buffer_and_rewrite(struct osst_tape * STp, struct osst_request ** aSRpnt,
1469						unsigned int frame, unsigned int skip, int pending)
1470{
1471	struct osst_request   * SRpnt = * aSRpnt;
1472	unsigned char	      * buffer, * p;
1473	unsigned char		cmd[MAX_COMMAND_SIZE];
1474	int			flag, new_frame, i;
1475	int			nframes          = STp->cur_frames;
1476	int			blks_per_frame   = ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1477	int			frame_seq_number = ntohl(STp->buffer->aux->frame_seq_num)
1478						- (nframes + pending - 1);
1479	int			logical_blk_num  = ntohl(STp->buffer->aux->logical_blk_num) 
1480						- (nframes + pending - 1) * blks_per_frame;
1481	char		      * name             = tape_name(STp);
1482	unsigned long		startwait        = jiffies;
1483#if DEBUG
1484	int			dbg              = debugging;
1485#endif
1486
1487	if ((buffer = vmalloc((nframes + 1) * OS_DATA_SIZE)) == NULL)
1488		return (-EIO);
1489
1490	printk(KERN_INFO "%s:I: Reading back %d frames from drive buffer%s\n",
1491			 name, nframes, pending?" and one that was pending":"");
1492
1493	osst_copy_from_buffer(STp->buffer, (p = &buffer[nframes * OS_DATA_SIZE]));
1494#if DEBUG
1495	if (pending && debugging)
1496		printk(OSST_DEB_MSG "%s:D: Pending frame %d (lblk %d), data %02x %02x %02x %02x\n",
1497				name, frame_seq_number + nframes,
1498			       	logical_blk_num + nframes * blks_per_frame,
1499			       	p[0], p[1], p[2], p[3]);
1500#endif
1501	for (i = 0, p = buffer; i < nframes; i++, p += OS_DATA_SIZE) {
1502
1503		memset(cmd, 0, MAX_COMMAND_SIZE);
1504		cmd[0] = 0x3C;		/* Buffer Read           */
1505		cmd[1] = 6;		/* Retrieve Faulty Block */
1506		cmd[7] = 32768 >> 8;
1507		cmd[8] = 32768 & 0xff;
1508
1509		SRpnt = osst_do_scsi(SRpnt, STp, cmd, OS_FRAME_SIZE, DMA_FROM_DEVICE,
1510					    STp->timeout, MAX_RETRIES, 1);
1511	
1512		if ((STp->buffer)->syscall_result || !SRpnt) {
1513			printk(KERN_ERR "%s:E: Failed to read frame back from OnStream buffer\n", name);
1514			vfree(buffer);
1515			*aSRpnt = SRpnt;
1516			return (-EIO);
1517		}
1518		osst_copy_from_buffer(STp->buffer, p);
1519#if DEBUG
1520		if (debugging)
1521			printk(OSST_DEB_MSG "%s:D: Read back logical frame %d, data %02x %02x %02x %02x\n",
1522					  name, frame_seq_number + i, p[0], p[1], p[2], p[3]);
1523#endif
1524	}
1525	*aSRpnt = SRpnt;
1526	osst_get_frame_position(STp, aSRpnt);
1527
1528#if DEBUG
1529	printk(OSST_DEB_MSG "%s:D: Frames left in buffer: %d\n", name, STp->cur_frames);
1530#endif
1531	/* Write synchronously so we can be sure we're OK again and don't have to recover recursively */
1532	/* In the header we don't actually re-write the frames that fail, just the ones after them */
1533
1534	for (flag=1, new_frame=frame, p=buffer, i=0; i < nframes + pending; ) {
1535
1536		if (flag) {
1537			if (STp->write_type == OS_WRITE_HEADER) {
1538				i += skip;
1539				p += skip * OS_DATA_SIZE;
1540			}
1541			else if (new_frame < 2990 && new_frame+skip+nframes+pending >= 2990)
1542				new_frame = 3000-i;
1543			else
1544				new_frame += skip;
1545#if DEBUG
1546			printk(OSST_DEB_MSG "%s:D: Position to frame %d, write fseq %d\n",
1547						name, new_frame+i, frame_seq_number+i);
1548#endif
1549			osst_set_frame_position(STp, aSRpnt, new_frame + i, 0);
1550			osst_wait_ready(STp, aSRpnt, 60, OSST_WAIT_POSITION_COMPLETE);
1551			osst_get_frame_position(STp, aSRpnt);
1552			SRpnt = * aSRpnt;
1553
1554			if (new_frame > frame + 1000) {
1555				printk(KERN_ERR "%s:E: Failed to find writable tape media\n", name);
1556				vfree(buffer);
1557				return (-EIO);
1558			}
1559			if ( i >= nframes + pending ) break;
1560			flag = 0;
1561		}
1562		osst_copy_to_buffer(STp->buffer, p);
1563		/*
1564		 * IMPORTANT: for error recovery to work, _never_ queue frames with mixed frame type!
1565		 */
1566		osst_init_aux(STp, STp->buffer->aux->frame_type, frame_seq_number+i,
1567			       	logical_blk_num + i*blks_per_frame,
1568			       	ntohl(STp->buffer->aux->dat.dat_list[0].blk_sz), blks_per_frame);
1569		memset(cmd, 0, MAX_COMMAND_SIZE);
1570		cmd[0] = WRITE_6;
1571		cmd[1] = 1;
1572		cmd[4] = 1;
1573
1574#if DEBUG
1575		if (debugging)
1576			printk(OSST_DEB_MSG
1577				"%s:D: About to write frame %d, seq %d, lbn %d, data %02x %02x %02x %02x\n",
1578				name, new_frame+i, frame_seq_number+i, logical_blk_num + i*blks_per_frame,
1579				p[0], p[1], p[2], p[3]);
1580#endif
1581		SRpnt = osst_do_scsi(SRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE,
1582					    STp->timeout, MAX_RETRIES, 1);
1583
1584		if (STp->buffer->syscall_result)
1585			flag = 1;
1586		else {
1587			p += OS_DATA_SIZE; i++;
1588
1589			/* if we just sent the last frame, wait till all successfully written */
1590			if ( i == nframes + pending ) {
1591#if DEBUG
1592				printk(OSST_DEB_MSG "%s:D: Check re-write successful\n", name);
1593#endif
1594				memset(cmd, 0, MAX_COMMAND_SIZE);
1595				cmd[0] = WRITE_FILEMARKS;
1596				cmd[1] = 1;
1597				SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
1598							    STp->timeout, MAX_RETRIES, 1);
1599#if DEBUG
1600				if (debugging) {
1601					printk(OSST_DEB_MSG "%s:D: Sleeping in re-write wait ready\n", name);
1602					printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
1603					debugging = 0;
1604				}
1605#endif
1606				flag = STp->buffer->syscall_result;
1607				while ( !flag && time_before(jiffies, startwait + 60*HZ) ) {
1608
1609					memset(cmd, 0, MAX_COMMAND_SIZE);
1610					cmd[0] = TEST_UNIT_READY;
1611
1612					SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout,
1613												MAX_RETRIES, 1);
1614
1615					if (SRpnt->sense[2] == 2 && SRpnt->sense[12] == 4 &&
1616					    (SRpnt->sense[13] == 1 || SRpnt->sense[13] == 8)) {
1617						/* in the process of becoming ready */
1618						msleep(100);
1619						continue;
1620					}
1621					if (STp->buffer->syscall_result)
1622						flag = 1;
1623					break;
1624				}
1625#if DEBUG
1626				debugging = dbg;
1627				printk(OSST_DEB_MSG "%s:D: Wait re-write finished\n", name);
1628#endif
1629			}
1630		}
1631		*aSRpnt = SRpnt;
1632		if (flag) {
1633			if ((SRpnt->sense[ 2] & 0x0f) == 13 &&
1634			     SRpnt->sense[12]         ==  0 &&
1635			     SRpnt->sense[13]         ==  2) {
1636				printk(KERN_ERR "%s:E: Volume overflow in write error recovery\n", name);
1637				vfree(buffer);
1638				return (-EIO);			/* hit end of tape = fail */
1639			}
1640			i = ((SRpnt->sense[3] << 24) |
1641			     (SRpnt->sense[4] << 16) |
1642			     (SRpnt->sense[5] <<  8) |
1643			      SRpnt->sense[6]        ) - new_frame;
1644			p = &buffer[i * OS_DATA_SIZE];
1645#if DEBUG
1646			printk(OSST_DEB_MSG "%s:D: Additional write error at %d\n", name, new_frame+i);
1647#endif
1648			osst_get_frame_position(STp, aSRpnt);
1649#if DEBUG
1650			printk(OSST_DEB_MSG "%s:D: reported frame positions: host = %d, tape = %d, buffer = %d\n",
1651					  name, STp->first_frame_position, STp->last_frame_position, STp->cur_frames);
1652#endif
1653		}
1654	}
1655	if (flag) {
1656		/* error recovery did not successfully complete */
1657		printk(KERN_ERR "%s:D: Write error recovery failed in %s\n", name,
1658				STp->write_type == OS_WRITE_HEADER?"header":"body");
1659	}
1660	if (!pending)
1661		osst_copy_to_buffer(STp->buffer, p);	/* so buffer content == at entry in all cases */
1662	vfree(buffer);
1663	return 0;
1664}
1665
1666static int osst_reposition_and_retry(struct osst_tape * STp, struct osst_request ** aSRpnt,
1667					unsigned int frame, unsigned int skip, int pending)
1668{
1669	unsigned char		cmd[MAX_COMMAND_SIZE];
1670	struct osst_request   * SRpnt;
1671	char		      * name      = tape_name(STp);
1672	int			expected  = 0;
1673	int			attempts  = 1000 / skip;
1674	int			flag      = 1;
1675	unsigned long		startwait = jiffies;
1676#if DEBUG
1677	int			dbg       = debugging;
1678#endif
1679
1680	while (attempts && time_before(jiffies, startwait + 60*HZ)) {
1681		if (flag) {
1682#if DEBUG
1683			debugging = dbg;
1684#endif
1685			if (frame < 2990 && frame+skip+STp->cur_frames+pending >= 2990)
1686				frame = 3000-skip;
1687			expected = frame+skip+STp->cur_frames+pending;
1688#if DEBUG
1689			printk(OSST_DEB_MSG "%s:D: Position to fppos %d, re-write from fseq %d\n",
1690					  name, frame+skip, STp->frame_seq_number-STp->cur_frames-pending);
1691#endif
1692			osst_set_frame_position(STp, aSRpnt, frame + skip, 1);
1693			flag = 0;
1694			attempts--;
1695			schedule_timeout_interruptible(msecs_to_jiffies(100));
1696		}
1697		if (osst_get_frame_position(STp, aSRpnt) < 0) {		/* additional write error */
1698#if DEBUG
1699			printk(OSST_DEB_MSG "%s:D: Addl error, host %d, tape %d, buffer %d\n",
1700					  name, STp->first_frame_position,
1701					  STp->last_frame_position, STp->cur_frames);
1702#endif
1703			frame = STp->last_frame_position;
1704			flag = 1;
1705			continue;
1706		}
1707		if (pending && STp->cur_frames < 50) {
1708
1709			memset(cmd, 0, MAX_COMMAND_SIZE);
1710			cmd[0] = WRITE_6;
1711			cmd[1] = 1;
1712			cmd[4] = 1;
1713#if DEBUG
1714			printk(OSST_DEB_MSG "%s:D: About to write pending fseq %d at fppos %d\n",
1715					  name, STp->frame_seq_number-1, STp->first_frame_position);
1716#endif
1717			SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE,
1718						      STp->timeout, MAX_RETRIES, 1);
1719			*aSRpnt = SRpnt;
1720
1721			if (STp->buffer->syscall_result) {		/* additional write error */
1722				if ((SRpnt->sense[ 2] & 0x0f) == 13 &&
1723				     SRpnt->sense[12]         ==  0 &&
1724				     SRpnt->sense[13]         ==  2) {
1725					printk(KERN_ERR
1726					       "%s:E: Volume overflow in write error recovery\n",
1727					       name);
1728					break;				/* hit end of tape = fail */
1729				}
1730				flag = 1;
1731			}
1732			else
1733				pending = 0;
1734
1735			continue;
1736		}
1737		if (STp->cur_frames == 0) {
1738#if DEBUG
1739			debugging = dbg;
1740			printk(OSST_DEB_MSG "%s:D: Wait re-write finished\n", name);
1741#endif
1742			if (STp->first_frame_position != expected) {
1743				printk(KERN_ERR "%s:A: Actual position %d - expected %d\n", 
1744						name, STp->first_frame_position, expected);
1745				return (-EIO);
1746			}
1747			return 0;
1748		}
1749#if DEBUG
1750		if (debugging) {
1751			printk(OSST_DEB_MSG "%s:D: Sleeping in re-write wait ready\n", name);
1752			printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
1753			debugging = 0;
1754		}
1755#endif
1756		schedule_timeout_interruptible(msecs_to_jiffies(100));
1757	}
1758	printk(KERN_ERR "%s:E: Failed to find valid tape media\n", name);
1759#if DEBUG
1760	debugging = dbg;
1761#endif
1762	return (-EIO);
1763}
1764
1765/*
1766 * Error recovery algorithm for the OnStream tape.
1767 */
1768
1769static int osst_write_error_recovery(struct osst_tape * STp, struct osst_request ** aSRpnt, int pending)
1770{
1771	struct osst_request * SRpnt  = * aSRpnt;
1772	struct st_partstat  * STps   = & STp->ps[STp->partition];
1773	char		    * name   = tape_name(STp);
1774	int		      retval = 0;
1775	int		      rw_state;
1776	unsigned int	      frame, skip;
1777
1778	rw_state = STps->rw;
1779
1780	if ((SRpnt->sense[ 2] & 0x0f) != 3
1781	  || SRpnt->sense[12]         != 12
1782	  || SRpnt->sense[13]         != 0) {
1783#if DEBUG
1784		printk(OSST_DEB_MSG "%s:D: Write error recovery cannot handle %02x:%02x:%02x\n", name,
1785			SRpnt->sense[2], SRpnt->sense[12], SRpnt->sense[13]);
1786#endif
1787		return (-EIO);
1788	}
1789	frame =	(SRpnt->sense[3] << 24) |
1790		(SRpnt->sense[4] << 16) |
1791		(SRpnt->sense[5] <<  8) |
1792		 SRpnt->sense[6];
1793	skip  =  SRpnt->sense[9];
1794 
1795#if DEBUG
1796	printk(OSST_DEB_MSG "%s:D: Detected physical bad frame at %u, advised to skip %d\n", name, frame, skip);
1797#endif
1798	osst_get_frame_position(STp, aSRpnt);
1799#if DEBUG
1800	printk(OSST_DEB_MSG "%s:D: reported frame positions: host = %d, tape = %d\n",
1801			name, STp->first_frame_position, STp->last_frame_position);
1802#endif
1803	switch (STp->write_type) {
1804	   case OS_WRITE_DATA:
1805	   case OS_WRITE_EOD:
1806	   case OS_WRITE_NEW_MARK:
1807		printk(KERN_WARNING 
1808			"%s:I: Relocating %d buffered logical frames from position %u to %u\n",
1809			name, STp->cur_frames, frame, (frame + skip > 3000 && frame < 3000)?3000:frame + skip);
1810		if (STp->os_fw_rev >= 10600)
1811			retval = osst_reposition_and_retry(STp, aSRpnt, frame, skip, pending);
1812		else
1813			retval = osst_read_back_buffer_and_rewrite(STp, aSRpnt, frame, skip, pending);
1814		printk(KERN_WARNING "%s:%s: %sWrite error%srecovered\n", name,
1815			       	retval?"E"    :"I",
1816			       	retval?""     :"Don't worry, ",
1817			       	retval?" not ":" ");
1818		break;
1819	   case OS_WRITE_LAST_MARK:
1820		printk(KERN_ERR "%s:E: Bad frame in update last marker, fatal\n", name);
1821		osst_set_frame_position(STp, aSRpnt, frame + STp->cur_frames + pending, 0);
1822		retval = -EIO;
1823		break;
1824	   case OS_WRITE_HEADER:
1825		printk(KERN_WARNING "%s:I: Bad frame in header partition, skipped\n", name);
1826		retval = osst_read_back_buffer_and_rewrite(STp, aSRpnt, frame, 1, pending);
1827		break;
1828	   default:
1829		printk(KERN_INFO "%s:I: Bad frame in filler, ignored\n", name);
1830		osst_set_frame_position(STp, aSRpnt, frame + STp->cur_frames + pending, 0);
1831	}
1832	osst_get_frame_position(STp, aSRpnt);
1833#if DEBUG
1834	printk(OSST_DEB_MSG "%s:D: Positioning complete, cur_frames %d, pos %d, tape pos %d\n", 
1835			name, STp->cur_frames, STp->first_frame_position, STp->last_frame_position);
1836	printk(OSST_DEB_MSG "%s:D: next logical frame to write: %d\n", name, STp->logical_blk_num);
1837#endif
1838	if (retval == 0) {
1839		STp->recover_count++;
1840		STp->recover_erreg++;
1841	} else
1842		STp->abort_count++;
1843
1844	STps->rw = rw_state;
1845	return retval;
1846}
1847
1848static int osst_space_over_filemarks_backward(struct osst_tape * STp, struct osst_request ** aSRpnt,
1849								 int mt_op, int mt_count)
1850{
1851	char  * name = tape_name(STp);
1852	int     cnt;
1853	int     last_mark_ppos = -1;
1854
1855#if DEBUG
1856	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_backwards %d %d\n", name, mt_op, mt_count);
1857#endif
1858	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1859#if DEBUG
1860		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_bwd\n", name);
1861#endif
1862		return -EIO;
1863	}
1864	if (STp->linux_media_version >= 4) {
1865		/*
1866		 * direct lookup in header filemark list
1867		 */
1868		cnt = ntohl(STp->buffer->aux->filemark_cnt);
1869		if (STp->header_ok                         && 
1870		    STp->header_cache != NULL              &&
1871		    (cnt - mt_count)  >= 0                 &&
1872		    (cnt - mt_count)   < OS_FM_TAB_MAX     &&
1873		    (cnt - mt_count)   < STp->filemark_cnt &&
1874		    STp->header_cache->dat_fm_tab.fm_tab_ent[cnt-1] == STp->buffer->aux->last_mark_ppos)
1875
1876			last_mark_ppos = ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt - mt_count]);
1877#if DEBUG
1878		if (STp->header_cache == NULL || (cnt - mt_count) < 0 || (cnt - mt_count) >= OS_FM_TAB_MAX)
1879			printk(OSST_DEB_MSG "%s:D: Filemark lookup fail due to %s\n", name,
1880			       STp->header_cache == NULL?"lack of header cache":"count out of range");
1881		else
1882			printk(OSST_DEB_MSG "%s:D: Filemark lookup: prev mark %d (%s), skip %d to %d\n",
1883				name, cnt,
1884				((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
1885				 (STp->header_cache->dat_fm_tab.fm_tab_ent[cnt-1] ==
1886					 STp->buffer->aux->last_mark_ppos))?"match":"error",
1887			       mt_count, last_mark_ppos);
1888#endif
1889		if (last_mark_ppos > 10 && last_mark_ppos < STp->eod_frame_ppos) {
1890			osst_position_tape_and_confirm(STp, aSRpnt, last_mark_ppos);
1891			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1892#if DEBUG
1893				printk(OSST_DEB_MSG 
1894					"%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1895#endif
1896				return (-EIO);
1897			}
1898			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
1899				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
1900						 name, last_mark_ppos);
1901				return (-EIO);
1902			}
1903			goto found;
1904		}
1905#if DEBUG
1906		printk(OSST_DEB_MSG "%s:D: Reverting to scan filemark backwards\n", name);
1907#endif
1908	}
1909	cnt = 0;
1910	while (cnt != mt_count) {
1911		last_mark_ppos = ntohl(STp->buffer->aux->last_mark_ppos);
1912		if (last_mark_ppos == -1)
1913			return (-EIO);
1914#if DEBUG
1915		printk(OSST_DEB_MSG "%s:D: Positioning to last mark at %d\n", name, last_mark_ppos);
1916#endif
1917		osst_position_tape_and_confirm(STp, aSRpnt, last_mark_ppos);
1918		cnt++;
1919		if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1920#if DEBUG
1921			printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1922#endif
1923			return (-EIO);
1924		}
1925		if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
1926			printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
1927					 name, last_mark_ppos);
1928			return (-EIO);
1929		}
1930	}
1931found:
1932	if (mt_op == MTBSFM) {
1933		STp->frame_seq_number++;
1934		STp->frame_in_buffer      = 0;
1935		STp->buffer->buffer_bytes = 0;
1936		STp->buffer->read_pointer = 0;
1937		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1938	}
1939	return 0;
1940}
1941
1942/*
1943 * ADRL 1.1 compatible "slow" space filemarks fwd version
1944 *
1945 * Just scans for the filemark sequentially.
1946 */
1947static int osst_space_over_filemarks_forward_slow(struct osst_tape * STp, struct osst_request ** aSRpnt,
1948								     int mt_op, int mt_count)
1949{
1950	int	cnt = 0;
1951#if DEBUG
1952	char  * name = tape_name(STp);
1953
1954	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_forward_slow %d %d\n", name, mt_op, mt_count);
1955#endif
1956	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1957#if DEBUG
1958		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_fwd\n", name);
1959#endif
1960		return (-EIO);
1961	}
1962	while (1) {
1963		if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1964#if DEBUG
1965			printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1966#endif
1967			return (-EIO);
1968		}
1969		if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER)
1970			cnt++;
1971		if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_EOD) {
1972#if DEBUG
1973			printk(OSST_DEB_MSG "%s:D: space_fwd: EOD reached\n", name);
1974#endif
1975			if (STp->first_frame_position > STp->eod_frame_ppos+1) {
1976#if DEBUG
1977				printk(OSST_DEB_MSG "%s:D: EOD position corrected (%d=>%d)\n",
1978					       	name, STp->eod_frame_ppos, STp->first_frame_position-1);
1979#endif
1980				STp->eod_frame_ppos = STp->first_frame_position-1;
1981			}
1982			return (-EIO);
1983		}
1984		if (cnt == mt_count)
1985			break;
1986		STp->frame_in_buffer = 0;
1987	}
1988	if (mt_op == MTFSF) {
1989		STp->frame_seq_number++;
1990		STp->frame_in_buffer      = 0;
1991		STp->buffer->buffer_bytes = 0;
1992		STp->buffer->read_pointer = 0;
1993		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1994	}
1995	return 0;
1996}
1997
1998/*
1999 * Fast linux specific version of OnStream FSF
2000 */
2001static int osst_space_over_filemarks_forward_fast(struct osst_tape * STp, struct osst_request ** aSRpnt,
2002								     int mt_op, int mt_count)
2003{
2004	char  * name = tape_name(STp);
2005	int	cnt  = 0,
2006		next_mark_ppos = -1;
2007
2008#if DEBUG
2009	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_forward_fast %d %d\n", name, mt_op, mt_count);
2010#endif
2011	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2012#if DEBUG
2013		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_fwd\n", name);
2014#endif
2015		return (-EIO);
2016	}
2017
2018	if (STp->linux_media_version >= 4) {
2019		/*
2020		 * direct lookup in header filemark list
2021		 */
2022		cnt = ntohl(STp->buffer->aux->filemark_cnt) - 1;
2023		if (STp->header_ok                         && 
2024		    STp->header_cache != NULL              &&
2025		    (cnt + mt_count)   < OS_FM_TAB_MAX     &&
2026		    (cnt + mt_count)   < STp->filemark_cnt &&
2027		    ((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
2028		     (STp->header_cache->dat_fm_tab.fm_tab_ent[cnt] == STp->buffer->aux->last_mark_ppos)))
2029
2030			next_mark_ppos = ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt + mt_count]);
2031#if DEBUG
2032		if (STp->header_cache == NULL || (cnt + mt_count) >= OS_FM_TAB_MAX)
2033			printk(OSST_DEB_MSG "%s:D: Filemark lookup fail due to %s\n", name,
2034			       STp->header_cache == NULL?"lack of header cache":"count out of range");
2035		else
2036			printk(OSST_DEB_MSG "%s:D: Filemark lookup: prev mark %d (%s), skip %d to %d\n",
2037			       name, cnt,
2038			       ((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
2039				(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt] ==
2040					 STp->buffer->aux->last_mark_ppos))?"match":"error",
2041			       mt_count, next_mark_ppos);
2042#endif
2043		if (next_mark_ppos <= 10 || next_mark_ppos > STp->eod_frame_ppos) {
2044#if DEBUG
2045			printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2046#endif
2047			return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count);
2048		} else {
2049			osst_position_tape_and_confirm(STp, aSRpnt, next_mark_ppos);
2050			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2051#if DEBUG
2052				printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n",
2053						 name);
2054#endif
2055				return (-EIO);
2056			}
2057			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2058				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
2059						 name, next_mark_ppos);
2060				return (-EIO);
2061			}
2062			if (ntohl(STp->buffer->aux->filemark_cnt) != cnt + mt_count) {
2063				printk(KERN_WARNING "%s:W: Expected to find marker %d at ppos %d, not %d\n",
2064						 name, cnt+mt_count, next_mark_ppos,
2065						 ntohl(STp->buffer->aux->filemark_cnt));
2066       				return (-EIO);
2067			}
2068		}
2069	} else {
2070		/*
2071		 * Find nearest (usually previous) marker, then jump from marker to marker
2072		 */
2073		while (1) {
2074			if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER)
2075				break;
2076			if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_EOD) {
2077#if DEBUG
2078				printk(OSST_DEB_MSG "%s:D: space_fwd: EOD reached\n", name);
2079#endif
2080				return (-EIO);
2081			}
2082			if (ntohl(STp->buffer->aux->filemark_cnt) == 0) {
2083				if (STp->first_mark_ppos == -1) {
2084#if DEBUG
2085					printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2086#endif
2087					return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count);
2088				}
2089				osst_position_tape_and_confirm(STp, aSRpnt, STp->first_mark_ppos);
2090				if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2091#if DEBUG
2092					printk(OSST_DEB_MSG
2093					       "%s:D: Couldn't get logical blk num in space_filemarks_fwd_fast\n",
2094					       name);
2095#endif
2096					return (-EIO);
2097				}
2098				if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2099					printk(KERN_WARNING "%s:W: Expected to find filemark at %d\n",
2100							 name, STp->first_mark_ppos);
2101					return (-EIO);
2102				}
2103			} else {
2104				if (osst_space_over_filemarks_backward(STp, aSRpnt, MTBSF, 1) < 0)
2105					return (-EIO);
2106				mt_count++;
2107			}
2108		}
2109		cnt++;
2110		while (cnt != mt_count) {
2111			next_mark_ppos = ntohl(STp->buffer->aux->next_mark_ppos);
2112			if (!next_mark_ppos || next_mark_ppos > STp->eod_frame_ppos) {
2113#if DEBUG
2114				printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2115#endif
2116				return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count - cnt);
2117			}
2118#if DEBUG
2119			else printk(OSST_DEB_MSG "%s:D: Positioning to next mark at %d\n", name, next_mark_ppos);
2120#endif
2121			osst_position_tape_and_confirm(STp, aSRpnt, next_mark_ppos);
2122			cnt++;
2123			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2124#if DEBUG
2125				printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n",
2126						 name);
2127#endif
2128				return (-EIO);
2129			}
2130			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2131				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
2132						 name, next_mark_ppos);
2133				return (-EIO);
2134			}
2135		}
2136	}
2137	if (mt_op == MTFSF) {
2138		STp->frame_seq_number++;
2139		STp->frame_in_buffer      = 0;
2140		STp->buffer->buffer_bytes = 0;
2141		STp->buffer->read_pointer = 0;
2142		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
2143	}
2144	return 0;
2145}
2146
2147/*
2148 * In debug mode, we want to see as many errors as possible
2149 * to test the error recovery mechanism.
2150 */
2151#if DEBUG
2152static void osst_set_retries(struct osst_tape * STp, struct osst_request ** aSRpnt, int retries)
2153{
2154	unsigned char		cmd[MAX_COMMAND_SIZE];
2155	struct osst_request   * SRpnt  = * aSRpnt;
2156	char		      * name   = tape_name(STp);
2157
2158	memset(cmd, 0, MAX_COMMAND_SIZE);
2159	cmd[0] = MODE_SELECT;
2160	cmd[1] = 0x10;
2161	cmd[4] = NUMBER_RETRIES_PAGE_LENGTH + MODE_HEADER_LENGTH;
2162
2163	(STp->buffer)->b_data[0] = cmd[4] - 1;
2164	(STp->buffer)->b_data[1] = 0;			/* Medium Type - ignoring */
2165	(STp->buffer)->b_data[2] = 0;			/* Reserved */
2166	(STp->buffer)->b_data[3] = 0;			/* Block Descriptor Length */
2167	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = NUMBER_RETRIES_PAGE | (1 << 7);
2168	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 2;
2169	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 4;
2170	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = retries;
2171
2172	if (debugging)
2173	    printk(OSST_DEB_MSG "%s:D: Setting number of retries on OnStream tape to %d\n", name, retries);
2174
2175	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2176	*aSRpnt = SRpnt;
2177
2178	if ((STp->buffer)->syscall_result)
2179	    printk (KERN_ERR "%s:D: Couldn't set retries to %d\n", name, retries);
2180}
2181#endif
2182
2183
2184static int osst_write_filemark(struct osst_tape * STp, struct osst_request ** aSRpnt)
2185{
2186	int	result;
2187	int	this_mark_ppos = STp->first_frame_position;
2188	int	this_mark_lbn  = STp->logical_blk_num;
2189#if DEBUG
2190	char  * name = tape_name(STp);
2191#endif
2192
2193	if (STp->raw) return 0;
2194
2195	STp->write_type = OS_WRITE_NEW_MARK;
2196#if DEBUG
2197	printk(OSST_DEB_MSG "%s:D: Writing Filemark %i at fppos %d (fseq %d, lblk %d)\n", 
2198	       name, STp->filemark_cnt, this_mark_ppos, STp->frame_seq_number, this_mark_lbn);
2199#endif
2200	STp->dirty = 1;
2201	result  = osst_flush_write_buffer(STp, aSRpnt);
2202	result |= osst_flush_drive_buffer(STp, aSRpnt);
2203	STp->last_mark_ppos = this_mark_ppos;
2204	STp->last_mark_lbn  = this_mark_lbn;
2205	if (STp->header_cache != NULL && STp->filemark_cnt < OS_FM_TAB_MAX)
2206		STp->header_cache->dat_fm_tab.fm_tab_ent[STp->filemark_cnt] = htonl(this_mark_ppos);
2207	if (STp->filemark_cnt++ == 0)
2208		STp->first_mark_ppos = this_mark_ppos;
2209	return result;
2210}
2211
2212static int osst_write_eod(struct osst_tape * STp, struct osst_request ** aSRpnt)
2213{
2214	int	result;
2215#if DEBUG
2216	char  * name = tape_name(STp);
2217#endif
2218
2219	if (STp->raw) return 0;
2220
2221	STp->write_type = OS_WRITE_EOD;
2222	STp->eod_frame_ppos = STp->first_frame_position;
2223#if DEBUG
2224	printk(OSST_DEB_MSG "%s:D: Writing EOD at fppos %d (fseq %d, lblk %d)\n", name,
2225			STp->eod_frame_ppos, STp->frame_seq_number, STp->logical_blk_num);
2226#endif
2227	STp->dirty = 1;
2228
2229	result  = osst_flush_write_buffer(STp, aSRpnt);	
2230	result |= osst_flush_drive_buffer(STp, aSRpnt);
2231	STp->eod_frame_lfa = --(STp->frame_seq_number);
2232	return result;
2233}
2234
2235static int osst_write_filler(struct osst_tape * STp, struct osst_request ** aSRpnt, int where, int count)
2236{
2237	char * name = tape_name(STp);
2238
2239#if DEBUG
2240	printk(OSST_DEB_MSG "%s:D: Reached onstream write filler group %d\n", name, where);
2241#endif
2242	osst_wait_ready(STp, aSRpnt, 60 * 5, 0);
2243	osst_set_frame_position(STp, aSRpnt, where, 0);
2244	STp->write_type = OS_WRITE_FILLER;
2245	while (count--) {
2246		memcpy(STp->buffer->b_data, "Filler", 6);
2247		STp->buffer->buffer_bytes = 6;
2248		STp->dirty = 1;
2249		if (osst_flush_write_buffer(STp, aSRpnt)) {
2250			printk(KERN_INFO "%s:I: Couldn't write filler frame\n", name);
2251			return (-EIO);
2252		}
2253	}
2254#if DEBUG
2255	printk(OSST_DEB_MSG "%s:D: Exiting onstream write filler group\n", name);
2256#endif
2257	return osst_flush_drive_buffer(STp, aSRpnt);
2258}
2259
2260static int __osst_write_header(struct osst_tape * STp, struct osst_request ** aSRpnt, int where, int count)
2261{
2262	char * name = tape_name(STp);
2263	int     result;
2264
2265#if DEBUG
2266	printk(OSST_DEB_MSG "%s:D: Reached onstream write header group %d\n", name, where);
2267#endif
2268	osst_wait_ready(STp, aSRpnt, 60 * 5, 0);
2269	osst_set_frame_position(STp, aSRpnt, where, 0);
2270	STp->write_type = OS_WRITE_HEADER;
2271	while (count--) {
2272		osst_copy_to_buffer(STp->buffer, (unsigned char *)STp->header_cache);
2273		STp->buffer->buffer_bytes = sizeof(os_header_t);
2274		STp->dirty = 1;
2275		if (osst_flush_write_buffer(STp, aSRpnt)) {
2276			printk(KERN_INFO "%s:I: Couldn't write header frame\n", name);
2277			return (-EIO);
2278		}
2279	}
2280	result = osst_flush_drive_buffer(STp, aSRpnt);
2281#if DEBUG
2282	printk(OSST_DEB_MSG "%s:D: Write onstream header group %s\n", name, result?"failed":"done");
2283#endif
2284	return result;
2285}
2286
2287static int osst_write_header(struct osst_tape * STp, struct osst_request ** aSRpnt, int locate_eod)
2288{
2289	os_header_t * header;
2290	int	      result;
2291	char        * name = tape_name(STp);
2292
2293#if DEBUG
2294	printk(OSST_DEB_MSG "%s:D: Writing tape header\n", name);
2295#endif
2296	if (STp->raw) return 0;
2297
2298	if (STp->header_cache == NULL) {
2299		if ((STp->header_cache = vmalloc(sizeof(os_header_t))) == NULL) {
2300			printk(KERN_ERR "%s:E: Failed to allocate header cache\n", name);
2301			return (-ENOMEM);
2302		}
2303		memset(STp->header_cache, 0, sizeof(os_header_t));
2304#if DEBUG
2305		printk(OSST_DEB_MSG "%s:D: Allocated and cleared memory for header cache\n", name);
2306#endif
2307	}
2308	if (STp->header_ok) STp->update_frame_cntr++;
2309	else                STp->update_frame_cntr = 0;
2310
2311	header = STp->header_cache;
2312	strcpy(header->ident_str, "ADR_SEQ");
2313	header->major_rev      = 1;
2314	header->minor_rev      = 4;
2315	header->ext_trk_tb_off = htons(17192);
2316	header->pt_par_num     = 1;
2317	header->partition[0].partition_num              = OS_DATA_PARTITION;
2318	header->partition[0].par_desc_ver               = OS_PARTITION_VERSION;
2319	header->partition[0].wrt_pass_cntr              = htons(STp->wrt_pass_cntr);
2320	header->partition[0].first_frame_ppos           = htonl(STp->first_data_ppos);
2321	header->partition[0].last_frame_ppos            = htonl(STp->capacity);
2322	header->partition[0].eod_frame_ppos             = htonl(STp->eod_frame_ppos);
2323	header->cfg_col_width                           = htonl(20);
2324	header->dat_col_width                           = htonl(1500);
2325	header->qfa_col_width                           = htonl(0);
2326	header->ext_track_tb.nr_stream_part             = 1;
2327	header->ext_track_tb.et_ent_sz                  = 32;
2328	header->ext_track_tb.dat_ext_trk_ey.et_part_num = 0;
2329	header->ext_track_tb.dat_ext_trk_ey.fmt         = 1;
2330	header->ext_track_tb.dat_ext_trk_ey.fm_tab_off  = htons(17736);
2331	header->ext_track_tb.dat_ext_trk_ey.last_hlb_hi = 0;
2332	header->ext_track_tb.dat_ext_trk_ey.last_hlb    = htonl(STp->eod_frame_lfa);
2333	header->ext_track_tb.dat_ext_trk_ey.last_pp	= htonl(STp->eod_frame_ppos);
2334	header->dat_fm_tab.fm_part_num                  = 0;
2335	header->dat_fm_tab.fm_tab_ent_sz                = 4;
2336	header->dat_fm_tab.fm_tab_ent_cnt               = htons(STp->filemark_cnt<OS_FM_TAB_MAX?
2337								STp->filemark_cnt:OS_FM_TAB_MAX);
2338
2339	result  = __osst_write_header(STp, aSRpnt, 0xbae, 5);
2340	if (STp->update_frame_cntr == 0)
2341		    osst_write_filler(STp, aSRpnt, 0xbb3, 5);
2342	result &= __osst_write_header(STp, aSRpnt,     5, 5);
2343
2344	if (locate_eod) {
2345#if DEBUG
2346		printk(OSST_DEB_MSG "%s:D: Locating back to eod frame addr %d\n", name, STp->eod_frame_ppos);
2347#endif
2348		osst_set_frame_position(STp, aSRpnt, STp->eod_frame_ppos, 0);
2349	}
2350	if (result)
2351		printk(KERN_ERR "%s:E: Write header failed\n", name);
2352	else {
2353		memcpy(STp->application_sig, "LIN4", 4);
2354		STp->linux_media         = 1;
2355		STp->linux_media_version = 4;
2356		STp->header_ok           = 1;
2357	}
2358	return result;
2359}
2360
2361static int osst_reset_header(struct osst_tape * STp, struct osst_request ** aSRpnt)
2362{
2363	if (STp->header_cache != NULL)
2364		memset(STp->header_cache, 0, sizeof(os_header_t));
2365
2366	STp->logical_blk_num = STp->frame_seq_number = 0;
2367	STp->frame_in_buffer = 0;
2368	STp->eod_frame_ppos = STp->first_data_ppos = 0x0000000A;
2369	STp->filemark_cnt = 0;
2370	STp->first_mark_ppos = STp->last_mark_ppos = STp->last_mark_lbn = -1;
2371	return osst_write_header(STp, aSRpnt, 1);
2372}
2373
2374static int __osst_analyze_headers(struct osst_tape * STp, struct osst_request ** aSRpnt, int ppos)
2375{
2376	char        * name = tape_name(STp);
2377	os_header_t * header;
2378	os_aux_t    * aux;
2379	char          id_string[8];
2380	int	      linux_media_version,
2381		      update_frame_cntr;
2382
2383	if (STp->raw)
2384		return 1;
2385
2386	if (ppos == 5 || ppos == 0xbae || STp->buffer->syscall_result) {
2387		if (osst_set_frame_position(STp, aSRpnt, ppos, 0))
2388			printk(KERN_WARNING "%s:W: Couldn't position tape\n", name);
2389		osst_wait_ready(STp, aSRpnt, 60 * 15, 0);
2390		if (osst_initiate_read (STp, aSRpnt)) {
2391			printk(KERN_WARNING "%s:W: Couldn't initiate read\n", name);
2392			return 0;
2393		}
2394	}
2395	if (osst_read_frame(STp, aSRpnt, 180)) {
2396#if DEBUG
2397		printk(OSST_DEB_MSG "%s:D: Couldn't read header frame\n", name);
2398#endif
2399		return 0;
2400	}
2401	header = (os_header_t *) STp->buffer->b_data;	/* warning: only first segment addressable */
2402	aux = STp->buffer->aux;
2403	if (aux->frame_type != OS_FRAME_TYPE_HEADER) {
2404#if DEBUG
2405		printk(OSST_DEB_MSG "%s:D: Skipping non-header frame (%d)\n", name, ppos);
2406#endif
2407		return 0;
2408	}
2409	if (ntohl(aux->frame_seq_num)              != 0                   ||
2410	    ntohl(aux->logical_blk_num)            != 0                   ||
2411	          aux->partition.partition_num     != OS_CONFIG_PARTITION ||
2412	    ntohl(aux->partition.first_frame_ppos) != 0                   ||
2413	    ntohl(aux->partition.last_frame_ppos)  != 0xbb7               ) {
2414#if DEBUG
2415		printk(OSST_DEB_MSG "%s:D: Invalid header frame (%d,%d,%d,%d,%d)\n", name,
2416				ntohl(aux->frame_seq_num), ntohl(aux->logical_blk_num),
2417			       	aux->partition.partition_num, ntohl(aux->partition.first_frame_ppos),
2418			       	ntohl(aux->partition.last_frame_ppos));
2419#endif
2420		return 0;
2421	}
2422	if (strncmp(header->ident_str, "ADR_SEQ", 7) != 0 &&
2423	    strncmp(header->ident_str, "ADR-SEQ", 7) != 0) {
2424		strlcpy(id_string, header->ident_str, 8);
2425#if DEBUG
2426		printk(OSST_DEB_MSG "%s:D: Invalid header identification string %s\n", name, id_string);
2427#endif
2428		return 0;
2429	}
2430	update_frame_cntr = ntohl(aux->update_frame_cntr);
2431	if (update_frame_cntr < STp->update_frame_cntr) {
2432#if DEBUG
2433		printk(OSST_DEB_MSG "%s:D: Skipping frame %d with update_frame_counter %d<%d\n",
2434				   name, ppos, update_frame_cntr, STp->update_frame_cntr);
2435#endif
2436		return 0;
2437	}
2438	if (header->major_rev != 1 || header->minor_rev != 4 ) {
2439#if DEBUG
2440		printk(OSST_DEB_MSG "%s:D: %s revision %d.%d detected (1.4 supported)\n", 
2441				 name, (header->major_rev != 1 || header->minor_rev < 2 || 
2442				       header->minor_rev  > 4 )? "Invalid" : "Warning:",
2443				 header->major_rev, header->minor_rev);
2444#endif
2445		if (header->major_rev != 1 || header->minor_rev < 2 || header->minor_rev > 4)
2446			return 0;
2447	}
2448#if DEBUG
2449	if (header->pt_par_num != 1)
2450		printk(KERN_INFO "%s:W: %d partitions defined, only one supported\n", 
2451				 name, header->pt_par_num);
2452#endif
2453	memcpy(id_string, aux->application_sig, 4);
2454	id_string[4] = 0;
2455	if (memcmp(id_string, "LIN", 3) == 0) {
2456		STp->linux_media = 1;
2457		linux_media_version = id_string[3] - '0';
2458		if (linux_media_version != 4)
2459			printk(KERN_INFO "%s:I: Linux media version %d detected (current 4)\n",
2460					 name, linux_media_version);
2461	} else {
2462		printk(KERN_WARNING "%s:W: Non Linux media detected (%s)\n", name, id_string);
2463		return 0;
2464	}
2465	if (linux_media_version < STp->linux_media_version) {
2466#if DEBUG
2467		printk(OSST_DEB_MSG "%s:D: Skipping frame %d with linux_media_version %d\n",
2468				  name, ppos, linux_media_version);
2469#endif
2470		return 0;
2471	}
2472	if (linux_media_version > STp->linux_media_version) {
2473#if DEBUG
2474		printk(OSST_DEB_MSG "%s:D: Frame %d sets linux_media_version to %d\n",
2475				   name, ppos, linux_media_version);
2476#endif
2477		memcpy(STp->application_sig, id_string, 5);
2478		STp->linux_media_version = linux_media_version;
2479		STp->update_frame_cntr = -1;
2480	}
2481	if (update_frame_cntr > STp->update_frame_cntr) {
2482#if DEBUG
2483		printk(OSST_DEB_MSG "%s:D: Frame %d sets update_frame_counter to %d\n",
2484				   name, ppos, update_frame_cntr);
2485#endif
2486		if (STp->header_cache == NULL) {
2487			if ((STp->header_cache = vmalloc(sizeof(os_header_t))) == NULL) {
2488				printk(KERN_ERR "%s:E: Failed to allocate header cache\n", name);
2489				return 0;
2490			}
2491#if DEBUG
2492			printk(OSST_DEB_MSG "%s:D: Allocated memory for header cache\n", name);
2493#endif
2494		}
2495		osst_copy_from_buffer(STp->buffer, (unsigned char *)STp->header_cache);
2496		header = STp->header_cache;	/* further accesses from cached (full) copy */
2497
2498		STp->wrt_pass_cntr     = ntohs(header->partition[0].wrt_pass_cntr);
2499		STp->first_data_ppos   = ntohl(header->partition[0].first_frame_ppos);
2500		STp->eod_frame_ppos    = ntohl(header->partition[0].eod_frame_ppos);
2501		STp->eod_frame_lfa     = ntohl(header->ext_track_tb.dat_ext_trk_ey.last_hlb);
2502		STp->filemark_cnt      = ntohl(aux->filemark_cnt);
2503		STp->first_mark_ppos   = ntohl(aux->next_mark_ppos);
2504		STp->last_mark_ppos    = ntohl(aux->last_mark_ppos);
2505		STp->last_mark_lbn     = ntohl(aux->last_mark_lbn);
2506		STp->update_frame_cntr = update_frame_cntr;
2507#if DEBUG
2508	printk(OSST_DEB_MSG "%s:D: Detected write pass %d, update frame counter %d, filemark counter %d\n",
2509			  name, STp->wrt_pass_cntr, STp->update_frame_cntr, STp->filemark_cnt);
2510	printk(OSST_DEB_MSG "%s:D: first data frame on tape = %d, last = %d, eod frame = %d\n", name,
2511			  STp->first_data_ppos,
2512			  ntohl(header->partition[0].last_frame_ppos),
2513			  ntohl(header->partition[0].eod_frame_ppos));
2514	printk(OSST_DEB_MSG "%s:D: first mark on tape = %d, last = %d, eod frame = %d\n", 
2515			  name, STp->first_mark_ppos, STp->last_mark_ppos, STp->eod_frame_ppos);
2516#endif
2517		if (header->minor_rev < 4 && STp->linux_media_version == 4) {
2518#if DEBUG
2519			printk(OSST_DEB_MSG "%s:D: Moving filemark list to ADR 1.4 location\n", name);
2520#endif
2521			memcpy((void *)header->dat_fm_tab.fm_tab_ent, 
2522			       (void *)header->old_filemark_list, sizeof(header->dat_fm_tab.fm_tab_ent));
2523			memset((void *)header->old_filemark_list, 0, sizeof(header->old_filemark_list));
2524		}
2525		if (header->minor_rev == 4   &&
2526		    (header->ext_trk_tb_off                          != htons(17192)               ||
2527		     header->partition[0].partition_num              != OS_DATA_PARTITION          ||
2528		     header->partition[0].par_desc_ver               != OS_PARTITION_VERSION       ||
2529		     header->partition[0].last_frame_ppos            != htonl(STp->capacity)       ||
2530		     header->cfg_col_width                           != htonl(20)                  ||
2531		     header->dat_col_width                           != htonl(1500)                ||
2532		     header->qfa_col_width                           != htonl(0)                   ||
2533		     header->ext_track_tb.nr_stream_part             != 1                          ||
2534		     header->ext_track_tb.et_ent_sz                  != 32                         ||
2535		     header->ext_track_tb.dat_ext_trk_ey.et_part_num != OS_DATA_PARTITION          ||
2536		     header->ext_track_tb.dat_ext_trk_ey.fmt         != 1                          ||
2537		     header->ext_track_tb.dat_ext_trk_ey.fm_tab_off  != htons(17736)               ||
2538		     header->ext_track_tb.dat_ext_trk_ey.last_hlb_hi != 0                          ||
2539		     header->ext_track_tb.dat_ext_trk_ey.last_pp     != htonl(STp->eod_frame_ppos) ||
2540		     header->dat_fm_tab.fm_part_num                  != OS_DATA_PARTITION          ||
2541		     header->dat_fm_tab.fm_tab_ent_sz                != 4                          ||
2542		     header->dat_fm_tab.fm_tab_ent_cnt               !=
2543			     htons(STp->filemark_cnt<OS_FM_TAB_MAX?STp->filemark_cnt:OS_FM_TAB_MAX)))
2544			printk(KERN_WARNING "%s:W: Failed consistency check ADR 1.4 format\n", name);
2545
2546	}
2547
2548	return 1;
2549}
2550
2551static int osst_analyze_headers(struct osst_tape * STp, struct osst_request ** aSRpnt)
2552{
2553	int	position, ppos;
2554	int	first, last;
2555	int	valid = 0;
2556	char  * name  = tape_name(STp);
2557
2558	position = osst_get_frame_position(STp, aSRpnt);
2559
2560	if (STp->raw) {
2561		STp->header_ok = STp->linux_media = 1;
2562		STp->linux_media_version = 0;
2563		return 1;
2564	}
2565	STp->header_ok = STp->linux_media = STp->linux_media_version = 0;
2566	STp->wrt_pass_cntr = STp->update_frame_cntr = -1;
2567	STp->eod_frame_ppos = STp->first_data_ppos = -1;
2568	STp->first_mark_ppos = STp->last_mark_ppos = STp->last_mark_lbn = -1;
2569#if DEBUG
2570	printk(OSST_DEB_MSG "%s:D: Reading header\n", name);
2571#endif
2572
2573	/* optimization for speed - if we are positioned at ppos 10, read second group first  */	
2574	/* TODO try the ADR 1.1 locations for the second group if we have no valid one yet... */
2575
2576	first = position==10?0xbae: 5;
2577	last  = position==10?0xbb3:10;
2578
2579	for (ppos = first; ppos < last; ppos++)
2580		if (__osst_analyze_headers(STp, aSRpnt, ppos))
2581			valid = 1;
2582
2583	first = position==10? 5:0xbae;
2584	last  = position==10?10:0xbb3;
2585
2586	for (ppos = first; ppos < last; ppos++)
2587		if (__osst_analyze_headers(STp, aSRpnt, ppos))
2588			valid = 1;
2589
2590	if (!valid) {
2591		printk(KERN_ERR "%s:E: Failed to find valid ADRL header, new media?\n", name);
2592		STp->eod_frame_ppos = STp->first_data_ppos = 0;
2593		osst_set_frame_position(STp, aSRpnt, 10, 0);
2594		return 0;
2595	}
2596	if (position <= STp->first_data_ppos) {
2597		position = STp->first_data_ppos;
2598		STp->ps[0].drv_file = STp->ps[0].drv_block = STp->frame_seq_number = STp->logical_blk_num = 0;
2599	}
2600	osst_set_frame_position(STp, aSRpnt, position, 0);
2601	STp->header_ok = 1;
2602
2603	return 1;
2604}
2605
2606static int osst_verify_position(struct osst_tape * STp, struct osst_request ** aSRpnt)
2607{
2608	int	frame_position  = STp->first_frame_position;
2609	int	frame_seq_numbr = STp->frame_seq_number;
2610	int	logical_blk_num = STp->logical_blk_num;
2611       	int	halfway_frame   = STp->frame_in_buffer;
2612	int	read_pointer    = STp->buffer->read_pointer;
2613	int	prev_mark_ppos  = -1;
2614	int	actual_mark_ppos, i, n;
2615#if DEBUG
2616	char  * name = tape_name(STp);
2617
2618	printk(OSST_DEB_MSG "%s:D: Verify that the tape is really the one we think before writing\n", name);
2619#endif
2620	osst_set_frame_position(STp, aSRpnt, frame_position - 1, 0);
2621	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2622#if DEBUG
2623		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in verify_position\n", name);
2624#endif
2625		return (-EIO);
2626	}
2627	if (STp->linux_media_version >= 4) {
2628		for (i=0; i<STp->filemark_cnt; i++)
2629			if ((n=ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[i])) < frame_position)
2630				prev_mark_ppos = n;
2631	} else
2632		prev_mark_ppos = frame_position - 1;  /* usually - we don't really know */
2633	actual_mark_ppos = STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER ?
2634				frame_position - 1 : ntohl(STp->buffer->aux->last_mark_ppos);
2635	if (frame_position  != STp->first_frame_position                   ||
2636	    frame_seq_numbr != STp->frame_seq_number + (halfway_frame?0:1) ||
2637	    prev_mark_ppos  != actual_mark_ppos                            ) {
2638#if DEBUG
2639		printk(OSST_DEB_MSG "%s:D: Block mismatch: fppos %d-%d, fseq %d-%d, mark %d-%d\n", name,
2640				  STp->first_frame_position, frame_position, 
2641				  STp->frame_seq_number + (halfway_frame?0:1),
2642				  frame_seq_numbr, actual_mark_ppos, prev_mark_ppos);
2643#endif
2644		return (-EIO);
2645	}
2646	if (halfway_frame) {
2647		/* prepare buffer for append and rewrite on top of original */
2648		osst_set_frame_position(STp, aSRpnt, frame_position - 1, 0);
2649		STp->buffer->buffer_bytes  = read_pointer;
2650		STp->ps[STp->partition].rw = ST_WRITING;
2651		STp->dirty                 = 1;
2652	}
2653	STp->frame_in_buffer  = halfway_frame;
2654	STp->frame_seq_number = frame_seq_numbr;
2655	STp->logical_blk_num  = logical_blk_num;
2656	return 0;
2657}
2658
2659/* Acc. to OnStream, the vers. numbering is the following:
2660 * X.XX for released versions (X=digit), 
2661 * XXXY for unreleased versions (Y=letter)
2662 * Ordering 1.05 < 106A < 106B < ...  < 106a < ... < 1.06
2663 * This fn makes monoton numbers out of this scheme ...
2664 */
2665static unsigned int osst_parse_firmware_rev (const char * str)
2666{
2667	if (str[1] == '.') {
2668		return (str[0]-'0')*10000
2669			+(str[2]-'0')*1000
2670			+(str[3]-'0')*100;
2671	} else {
2672		return (str[0]-'0')*10000
2673			+(str[1]-'0')*1000
2674			+(str[2]-'0')*100 - 100
2675			+(str[3]-'@');
2676	}
2677}
2678
2679/*
2680 * Configure the OnStream SCII tape drive for default operation
2681 */
2682static int osst_configure_onstream(struct osst_tape *STp, struct osst_request ** aSRpnt)
2683{
2684	unsigned char                  cmd[MAX_COMMAND_SIZE];
2685	char                         * name = tape_name(STp);
2686	struct osst_request          * SRpnt = * aSRpnt;
2687	osst_mode_parameter_header_t * header;
2688	osst_block_size_page_t       * bs;
2689	osst_capabilities_page_t     * cp;
2690	osst_tape_paramtr_page_t     * prm;
2691	int                            drive_buffer_size;
2692
2693	if (STp->ready != ST_READY) {
2694#if DEBUG
2695	    printk(OSST_DEB_MSG "%s:D: Not Ready\n", name);
2696#endif
2697	    return (-EIO);
2698	}
2699	
2700	if (STp->os_fw_rev < 10600) {
2701	    printk(KERN_INFO "%s:I: Old OnStream firmware revision detected (%s),\n", name, STp->device->rev);
2702	    printk(KERN_INFO "%s:I: an upgrade to version 1.06 or above is recommended\n", name);
2703	}
2704
2705	/*
2706	 * Configure 32.5KB (data+aux) frame size.
2707         * Get the current frame size from the block size mode page
2708	 */
2709	memset(cmd, 0, MAX_COMMAND_SIZE);
2710	cmd[0] = MODE_SENSE;
2711	cmd[1] = 8;
2712	cmd[2] = BLOCK_SIZE_PAGE;
2713	cmd[4] = BLOCK_SIZE_PAGE_LENGTH + MODE_HEADER_LENGTH;
2714
2715	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2716	if (SRpnt == NULL) {
2717#if DEBUG
2718 	    printk(OSST_DEB_MSG "osst :D: Busy\n");
2719#endif
2720	    return (-EBUSY);
2721	}
2722	*aSRpnt = SRpnt;
2723	if ((STp->buffer)->syscall_result != 0) {
2724	    printk (KERN_ERR "%s:E: Can't get tape block size mode page\n", name);
2725	    return (-EIO);
2726	}
2727
2728	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2729	bs = (osst_block_size_page_t *) ((STp->buffer)->b_data + sizeof(osst_mode_parameter_header_t) + header->bdl);
2730
2731#if DEBUG
2732	printk(OSST_DEB_MSG "%s:D: 32KB play back: %s\n",   name, bs->play32     ? "Yes" : "No");
2733	printk(OSST_DEB_MSG "%s:D: 32.5KB play back: %s\n", name, bs->play32_5   ? "Yes" : "No");
2734	printk(OSST_DEB_MSG "%s:D: 32KB record: %s\n",      name, bs->record32   ? "Yes" : "No");
2735	printk(OSST_DEB_MSG "%s:D: 32.5KB record: %s\n",    name, bs->record32_5 ? "Yes" : "No");
2736#endif
2737
2738	/*
2739	 * Configure default auto columns mode, 32.5KB transfer mode
2740	 */ 
2741	bs->one = 1;
2742	bs->play32 = 0;
2743	bs->play32_5 = 1;
2744	bs->record32 = 0;
2745	bs->record32_5 = 1;
2746
2747	memset(cmd, 0, MAX_COMMAND_SIZE);
2748	cmd[0] = MODE_SELECT;
2749	cmd[1] = 0x10;
2750	cmd[4] = BLOCK_SIZE_PAGE_LENGTH + MODE_HEADER_LENGTH;
2751
2752	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2753	*aSRpnt = SRpnt;
2754	if ((STp->buffer)->syscall_result != 0) {
2755	    printk (KERN_ERR "%s:E: Couldn't set tape block size mode page\n", name);
2756	    return (-EIO);
2757	}
2758
2759#if DEBUG
2760	printk(KERN_INFO "%s:D: Drive Block Size changed to 32.5K\n", name);
2761	 /*
2762	 * In debug mode, we want to see as many errors as possible
2763	 * to test the error recovery mechanism.
2764	 */
2765	osst_set_retries(STp, aSRpnt, 0);
2766	SRpnt = * aSRpnt;
2767#endif
2768
2769	/*
2770	 * Set vendor name to 'LIN4' for "Linux support version 4".
2771	 */
2772
2773	memset(cmd, 0, MAX_COMMAND_SIZE);
2774	cmd[0] = MODE_SELECT;
2775	cmd[1] = 0x10;
2776	cmd[4] = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH;
2777
2778	header->mode_data_length = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH - 1;
2779	header->medium_type      = 0;	/* Medium Type - ignoring */
2780	header->dsp              = 0;	/* Reserved */
2781	header->bdl              = 0;	/* Block Descriptor Length */
2782	
2783	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = VENDOR_IDENT_PAGE | (1 << 7);
2784	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 6;
2785	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 'L';
2786	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = 'I';
2787	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 4] = 'N';
2788	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 5] = '4';
2789	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 6] = 0;
2790	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 7] = 0;
2791
2792	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2793	*aSRpnt = SRpnt;
2794
2795	if ((STp->buffer)->syscall_result != 0) {
2796	    printk (KERN_ERR "%s:E: Couldn't set vendor name to %s\n", name, 
2797			(char *) ((STp->buffer)->b_data + MODE_HEADER_LENGTH + 2));
2798	    return (-EIO);
2799	}
2800
2801	memset(cmd, 0, MAX_COMMAND_SIZE);
2802	cmd[0] = MODE_SENSE;
2803	cmd[1] = 8;
2804	cmd[2] = CAPABILITIES_PAGE;
2805	cmd[4] = CAPABILITIES_PAGE_LENGTH + MODE_HEADER_LENGTH;
2806
2807	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2808	*aSRpnt = SRpnt;
2809
2810	if ((STp->buffer)->syscall_result != 0) {
2811	    printk (KERN_ERR "%s:E: Can't get capabilities page\n", name);
2812	    return (-EIO);
2813	}
2814
2815	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2816	cp     = (osst_capabilities_page_t    *) ((STp->buffer)->b_data +
2817		 sizeof(osst_mode_parameter_header_t) + header->bdl);
2818
2819	drive_buffer_size = ntohs(cp->buffer_size) / 2;
2820
2821	memset(cmd, 0, MAX_COMMAND_SIZE);
2822	cmd[0] = MODE_SENSE;
2823	cmd[1] = 8;
2824	cmd[2] = TAPE_PARAMTR_PAGE;
2825	cmd[4] = TAPE_PARAMTR_PAGE_LENGTH + MODE_HEADER_LENGTH;
2826
2827	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2828	*aSRpnt = SRpnt;
2829
2830	if ((STp->buffer)->syscall_result != 0) {
2831	    printk (KERN_ERR "%s:E: Can't get tape parameter page\n", name);
2832	    return (-EIO);
2833	}
2834
2835	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2836	prm    = (osst_tape_paramtr_page_t    *) ((STp->buffer)->b_data +
2837		 sizeof(osst_mode_parameter_header_t) + header->bdl);
2838
2839	STp->density  = prm->density;
2840	STp->capacity = ntohs(prm->segtrk) * ntohs(prm->trks);
2841#if DEBUG
2842	printk(OSST_DEB_MSG "%s:D: Density %d, tape length: %dMB, drive buffer size: %dKB\n",
2843			  name, STp->density, STp->capacity / 32, drive_buffer_size);
2844#endif
2845
2846	return 0;
2847	
2848}
2849
2850
2851/* Step over EOF if it has been inadvertently crossed (ioctl not used because
2852   it messes up the block number). */
2853static int cross_eof(struct osst_tape *STp, struct osst_request ** aSRpnt, int forward)
2854{
2855	int	result;
2856	char  * name = tape_name(STp);
2857
2858#if DEBUG
2859	if (debugging)
2860		printk(OSST_DEB_MSG "%s:D: Stepping over filemark %s.\n",
2861	   			  name, forward ? "forward" : "backward");
2862#endif
2863
2864	if (forward) {
2865	   /* assumes that the filemark is already read by the drive, so this is low cost */
2866	   result = osst_space_over_filemarks_forward_slow(STp, aSRpnt, MTFSF, 1);
2867	}
2868	else
2869	   /* assumes this is only called if we just read the filemark! */
2870	   result = osst_seek_logical_blk(STp, aSRpnt, STp->logical_blk_num - 1);
2871
2872	if (result < 0)
2873	   printk(KERN_WARNING "%s:W: Stepping over filemark %s failed.\n",
2874				name, forward ? "forward" : "backward");
2875
2876	return result;
2877}
2878
2879
2880/* Get the tape position. */
2881
2882static int osst_get_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt)
2883{
2884	unsigned char		scmd[MAX_COMMAND_SIZE];
2885	struct osst_request   * SRpnt;
2886	int			result = 0;
2887	char    	      * name   = tape_name(STp);
2888
2889	/* KG: We want to be able to use it for checking Write Buffer availability
2890	 *  and thus don't want to risk to overwrite anything. Exchange buffers ... */
2891	char		mybuf[24];
2892	char	      * olddata = STp->buffer->b_data;
2893	int		oldsize = STp->buffer->buffer_size;
2894
2895	if (STp->ready != ST_READY) return (-EIO);
2896
2897	memset (scmd, 0, MAX_COMMAND_SIZE);
2898	scmd[0] = READ_POSITION;
2899
2900	STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
2901	SRpnt = osst_do_scsi(*aSRpnt, STp, scmd, 20, DMA_FROM_DEVICE,
2902				      STp->timeout, MAX_RETRIES, 1);
2903	if (!SRpnt) {
2904		STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
2905		return (-EBUSY);
2906	}
2907	*aSRpnt = SRpnt;
2908
2909	if (STp->buffer->syscall_result)
2910		result = ((SRpnt->sense[2] & 0x0f) == 3) ? -EIO : -EINVAL;	/* 3: Write Error */
2911
2912	if (result == -EINVAL)
2913		printk(KERN_ERR "%s:E: Can't read tape position.\n", name);
2914	else {
2915		if (result == -EIO) {	/* re-read position - this needs to preserve media errors */
2916			unsigned char mysense[16];
2917			memcpy (mysense, SRpnt->sense, 16);
2918			memset (scmd, 0, MAX_COMMAND_SIZE);
2919			scmd[0] = READ_POSITION;
2920			STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
2921			SRpnt = osst_do_scsi(SRpnt, STp, scmd, 20, DMA_FROM_DEVICE,
2922						    STp->timeout, MAX_RETRIES, 1);
2923#if DEBUG
2924			printk(OSST_DEB_MSG "%s:D: Reread position, reason=[%02x:%02x:%02x], result=[%s%02x:%02x:%02x]\n",
2925					name, mysense[2], mysense[12], mysense[13], STp->buffer->syscall_result?"":"ok:",
2926					SRpnt->sense[2],SRpnt->sense[12],SRpnt->sense[13]);
2927#endif
2928			if (!STp->buffer->syscall_result)
2929				memcpy (SRpnt->sense, mysense, 16);
2930			else
2931				printk(KERN_WARNING "%s:W: Double error in get position\n", name);
2932		}
2933		STp->first_frame_position = ((STp->buffer)->b_data[4] << 24)
2934					  + ((STp->buffer)->b_data[5] << 16)
2935					  + ((STp->buffer)->b_data[6] << 8)
2936					  +  (STp->buffer)->b_data[7];
2937		STp->last_frame_position  = ((STp->buffer)->b_data[ 8] << 24)
2938					  + ((STp->buffer)->b_data[ 9] << 16)
2939					  + ((STp->buffer)->b_data[10] <<  8)
2940					  +  (STp->buffer)->b_data[11];
2941		STp->cur_frames           =  (STp->buffer)->b_data[15];
2942#if DEBUG
2943		if (debugging) {
2944			printk(OSST_DEB_MSG "%s:D: Drive Positions: host %d, tape %d%s, buffer %d\n", name,
2945					    STp->first_frame_position, STp->last_frame_position,
2946					    ((STp->buffer)->b_data[0]&0x80)?" (BOP)":
2947					    ((STp->buffer)->b_data[0]&0x40)?" (EOP)":"",
2948					    STp->cur_frames);
2949		}
2950#endif
2951		if (STp->cur_frames == 0 && STp->first_frame_position != STp->last_frame_position) {
2952#if DEBUG
2953			printk(OSST_DEB_MSG "%s:D: Correcting read position %d, %d, %d\n", name,
2954					STp->first_frame_position, STp->last_frame_position, STp->cur_frames);
2955#endif
2956			STp->first_frame_position = STp->last_frame_position;
2957		}
2958	}
2959	STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
2960
2961	return (result == 0 ? STp->first_frame_position : result);
2962}
2963
2964
2965/* Set the tape block */
2966static int osst_set_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt, int ppos, int skip)
2967{
2968	unsigned char		scmd[MAX_COMMAND_SIZE];
2969	struct osst_request   * SRpnt;
2970	struct st_partstat    * STps;
2971	int			result = 0;
2972	int			pp     = (ppos == 3000 && !skip)? 0 : ppos;
2973	char		      * name   = tape_name(STp);
2974
2975	if (STp->ready != ST_READY) return (-EIO);
2976
2977	STps = &(STp->ps[STp->partition]);
2978
2979	if (ppos < 0 || ppos > STp->capacity) {
2980		printk(KERN_WARNING "%s:W: Reposition request %d out of range\n", name, ppos);
2981		pp = ppos = ppos < 0 ? 0 : (STp->capacity - 1);
2982		result = (-EINVAL);
2983	}
2984
2985	do {
2986#if DEBUG
2987		if (debugging)
2988			printk(OSST_DEB_MSG "%s:D: Setting ppos to %d.\n", name, pp);
2989#endif
2990		memset (scmd, 0, MAX_COMMAND_SIZE);
2991		scmd[0] = SEEK_10;
2992		scmd[1] = 1;
2993		scmd[3] = (pp >> 24);
2994		scmd[4] = (pp >> 16);
2995		scmd[5] = (pp >> 8);
2996		scmd[6] =  pp;
2997		if (skip)
2998			scmd[9] = 0x80;
2999
3000		SRpnt = osst_do_scsi(*aSRpnt, STp, scmd, 0, DMA_NONE, STp->long_timeout,
3001								MAX_RETRIES, 1);
3002		if (!SRpnt)
3003			return (-EBUSY);
3004		*aSRpnt  = SRpnt;
3005
3006		if ((STp->buffer)->syscall_result != 0) {
3007#if DEBUG
3008			printk(OSST_DEB_MSG "%s:D: SEEK command from %d to %d failed.\n",
3009					name, STp->first_frame_position, pp);
3010#endif
3011			result = (-EIO);
3012		}
3013		if (pp != ppos)
3014			osst_wait_ready(STp, aSRpnt, 5 * 60, OSST_WAIT_POSITION_COMPLETE);
3015	} while ((pp != ppos) && (pp = ppos));
3016	STp->first_frame_position = STp->last_frame_position = ppos;
3017	STps->eof = ST_NOEOF;
3018	STps->at_sm = 0;
3019	STps->rw = ST_IDLE;
3020	STp->frame_in_buffer = 0;
3021	return result;
3022}
3023
3024static int osst_write_trailer(struct osst_tape *STp, struct osst_request ** aSRpnt, int leave_at_EOT)
3025{
3026	struct st_partstat * STps = &(STp->ps[STp->partition]);
3027	int result = 0;
3028
3029	if (STp->write_type != OS_WRITE_NEW_MARK) {
3030		/* true unless the user wrote the filemark for us */
3031		result = osst_flush_drive_buffer(STp, aSRpnt);
3032		if (result < 0) goto out;
3033		result = osst_write_filemark(STp, aSRpnt);
3034		if (result < 0) goto out;
3035
3036		if (STps->drv_file >= 0)
3037			STps->drv_file++ ;
3038		STps->drv_block = 0;
3039	}
3040	result = osst_write_eod(STp, aSRpnt);
3041	osst_write_header(STp, aSRpnt, leave_at_EOT);
3042
3043	STps->eof = ST_FM;
3044out:
3045	return result;
3046}
3047
3048/* osst versions of st functions - augmented and stripped to suit OnStream only */
3049
3050/* Flush the write buffer (never need to write if variable blocksize). */
3051static int osst_flush_write_buffer(struct osst_tape *STp, struct osst_request ** aSRpnt)
3052{
3053	int			offset, transfer, blks = 0;
3054	int			result = 0;
3055	unsigned char		cmd[MAX_COMMAND_SIZE];
3056	struct osst_request   * SRpnt = *aSRpnt;
3057	struct st_partstat    * STps;
3058	char		      * name = tape_name(STp);
3059
3060	if ((STp->buffer)->writing) {
3061		if (SRpnt == (STp->buffer)->last_SRpnt)
3062#if DEBUG
3063			{ printk(OSST_DEB_MSG
3064	 "%s:D: aSRpnt points to osst_request that write_behind_check will release -- cleared\n", name);
3065#endif
3066			*aSRpnt = SRpnt = NULL;
3067#if DEBUG
3068			} else if (SRpnt)
3069				printk(OSST_DEB_MSG
3070	 "%s:D: aSRpnt does not point to osst_request that write_behind_check will release -- strange\n", name);
3071#endif	
3072		osst_write_behind_check(STp);
3073		if ((STp->buffer)->syscall_result) {
3074#if DEBUG
3075			if (debugging)
3076				printk(OSST_DEB_MSG "%s:D: Async write error (flush) %x.\n",
3077				       name, (STp->buffer)->midlevel_result);
3078#endif
3079			if ((STp->buffer)->midlevel_result == INT_MAX)
3080				return (-ENOSPC);
3081			return (-EIO);
3082		}
3083	}
3084
3085	result = 0;
3086	if (STp->dirty == 1) {
3087
3088		STp->write_count++;
3089		STps     = &(STp->ps[STp->partition]);
3090		STps->rw = ST_WRITING;
3091		offset   = STp->buffer->buffer_bytes;
3092		blks     = (offset + STp->block_size - 1) / STp->block_size;
3093		transfer = OS_FRAME_SIZE;
3094		
3095		if (offset < OS_DATA_SIZE)
3096			osst_zero_buffer_tail(STp->buffer);
3097
3098		if (STp->poll)
3099			if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, -50, 120))
3100				result = osst_recover_wait_frame(STp, aSRpnt, 1);
3101
3102		memset(cmd, 0, MAX_COMMAND_SIZE);
3103		cmd[0] = WRITE_6;
3104		cmd[1] = 1;
3105		cmd[4] = 1;
3106
3107		switch	(STp->write_type) {
3108		   case OS_WRITE_DATA:
3109#if DEBUG
3110   			if (debugging)
3111				printk(OSST_DEB_MSG "%s:D: Writing %d blocks to frame %d, lblks %d-%d\n",
3112					name, blks, STp->frame_seq_number, 
3113					STp->logical_blk_num - blks, STp->logical_blk_num - 1);
3114#endif
3115			osst_init_aux(STp, OS_FRAME_TYPE_DATA, STp->frame_seq_number++,
3116				      STp->logical_blk_num - blks, STp->block_size, blks);
3117			break;
3118		   case OS_WRITE_EOD:
3119			osst_init_aux(STp, OS_FRAME_TYPE_EOD, STp->frame_seq_number++,
3120				      STp->logical_blk_num, 0, 0);
3121			break;
3122		   case OS_WRITE_NEW_MARK:
3123			osst_init_aux(STp, OS_FRAME_TYPE_MARKER, STp->frame_seq_number++,
3124				      STp->logical_blk_num++, 0, blks=1);
3125			break;
3126		   case OS_WRITE_HEADER:
3127			osst_init_aux(STp, OS_FRAME_TYPE_HEADER, 0, 0, 0, blks=0);
3128			break;
3129		default: /* probably FILLER */
3130			osst_init_aux(STp, OS_FRAME_TYPE_FILL, 0, 0, 0, 0);
3131		}
3132#if DEBUG
3133		if (debugging)
3134			printk(OSST_DEB_MSG "%s:D: Flushing %d bytes, Transferring %d bytes in %d lblocks.\n",
3135			  			 name, offset, transfer, blks);
3136#endif
3137
3138		SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
3139					      STp->timeout, MAX_RETRIES, 1);
3140		*aSRpnt = SRpnt;
3141		if (!SRpnt)
3142			return (-EBUSY);
3143
3144		if ((STp->buffer)->syscall_result != 0) {
3145#if DEBUG
3146			printk(OSST_DEB_MSG
3147				"%s:D: write sense [0]=0x%02x [2]=%02x [12]=%02x [13]=%02x\n",
3148				name, SRpnt->sense[0], SRpnt->sense[2],
3149				SRpnt->sense[12], SRpnt->sense[13]);
3150#endif
3151			if ((SRpnt->sense[0] & 0x70) == 0x70 &&
3152			    (SRpnt->sense[2] & 0x40) && /* FIXME - SC-30 drive doesn't assert EOM bit */
3153			    (SRpnt->sense[2] & 0x0f) == NO_SENSE) {
3154				STp->dirty = 0;
3155				(STp->buffer)->buffer_bytes = 0;
3156				result = (-ENOSPC);
3157			}
3158			else {
3159				if (osst_write_error_recovery(STp, aSRpnt, 1)) {
3160					printk(KERN_ERR "%s:E: Error on flush write.\n", name);
3161					result = (-EIO);
3162				}
3163			}
3164			STps->drv_block = (-1);		/* FIXME - even if write recovery succeeds? */
3165		}
3166		else {
3167			STp->first_frame_position++;
3168			STp->dirty = 0;
3169			(STp->buffer)->buffer_bytes = 0;
3170		}
3171	}
3172#if DEBUG
3173	printk(OSST_DEB_MSG "%s:D: Exit flush write buffer with code %d\n", name, result);
3174#endif
3175	return result;
3176}
3177
3178
3179/* Flush the tape buffer. The tape will be positioned correctly unless
3180   seek_next is true. */
3181static int osst_flush_buffer(struct osst_tape * STp, struct osst_request ** aSRpnt, int seek_next)
3182{
3183	struct st_partstat * STps;
3184	int    backspace = 0, result = 0;
3185#if DEBUG
3186	char * name = tape_name(STp);
3187#endif
3188
3189	/*
3190	 * If there was a bus reset, block further access
3191	 * to this device.
3192	 */
3193	if( STp->pos_unknown)
3194		return (-EIO);
3195
3196	if (STp->ready != ST_READY)
3197		return 0;
3198
3199	STps = &(STp->ps[STp->partition]);
3200	if (STps->rw == ST_WRITING || STp->dirty) {	/* Writing */
3201		STp->write_type = OS_WRITE_DATA;
3202		return osst_flush_write_buffer(STp, aSRpnt);
3203	}
3204	if (STp->block_size == 0)
3205		return 0;
3206
3207#if DEBUG
3208	printk(OSST_DEB_MSG "%s:D: Reached flush (read) buffer\n", name);
3209#endif
3210
3211	if (!STp->can_bsr) {
3212		backspace = ((STp->buffer)->buffer_bytes + (STp->buffer)->read_pointer) / STp->block_size -
3213			    ((STp->buffer)->read_pointer + STp->block_size - 1        ) / STp->block_size ;
3214		(STp->buffer)->buffer_bytes = 0;
3215		(STp->buffer)->read_pointer = 0;
3216		STp->frame_in_buffer = 0;		/* FIXME is this relevant w. OSST? */
3217	}
3218
3219	if (!seek_next) {
3220		if (STps->eof == ST_FM_HIT) {
3221			result = cross_eof(STp, aSRpnt, 0); /* Back over the EOF hit */
3222			if (!result)
3223				STps->eof = ST_NOEOF;
3224			else {
3225				if (STps->drv_file >= 0)
3226					STps->drv_file++;
3227				STps->drv_block = 0;
3228			}
3229		}
3230		if (!result && backspace > 0)	/* TODO -- design and run a test case for this */
3231			result = osst_seek_logical_blk(STp, aSRpnt, STp->logical_blk_num - backspace);
3232	}
3233	else if (STps->eof == ST_FM_HIT) {
3234		if (STps->drv_file >= 0)
3235			STps->drv_file++;
3236		STps->drv_block = 0;
3237		STps->eof = ST_NOEOF;
3238	}
3239
3240	return result;
3241}
3242
3243static int osst_write_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int synchronous)
3244{
3245	unsigned char		cmd[MAX_COMMAND_SIZE];
3246	struct osst_request   * SRpnt;
3247	int			blks;
3248#if DEBUG
3249	char		      * name = tape_name(STp);
3250#endif
3251
3252	if ((!STp-> raw) && (STp->first_frame_position == 0xbae)) { /* _must_ preserve buffer! */
3253#if DEBUG
3254		printk(OSST_DEB_MSG "%s:D: Reaching config partition.\n", name);
3255#endif
3256		if (osst_flush_drive_buffer(STp, aSRpnt) < 0) {
3257			return (-EIO);
3258		}
3259		/* error recovery may have bumped us past the header partition */
3260		if (osst_get_frame_position(STp, aSRpnt) < 0xbb8) {
3261#if DEBUG
3262			printk(OSST_DEB_MSG "%s:D: Skipping over config partition.\n", name);
3263#endif
3264		osst_position_tape_and_confirm(STp, aSRpnt, 0xbb8);
3265		}
3266	}
3267
3268	if (STp->poll)
3269		if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, -48, 120))
3270			if (osst_recover_wait_frame(STp, aSRpnt, 1))
3271				return (-EIO);
3272
3273//	osst_build_stats(STp, &SRpnt);
3274
3275	STp->ps[STp->partition].rw = ST_WRITING;
3276	STp->write_type            = OS_WRITE_DATA;
3277			
3278	memset(cmd, 0, MAX_COMMAND_SIZE);
3279	cmd[0]   = WRITE_6;
3280	cmd[1]   = 1;
3281	cmd[4]   = 1;						/* one frame at a time... */
3282	blks     = STp->buffer->buffer_bytes / STp->block_size;
3283#if DEBUG
3284	if (debugging)
3285		printk(OSST_DEB_MSG "%s:D: Writing %d blocks to frame %d, lblks %d-%d\n", name, blks, 
3286			STp->frame_seq_number, STp->logical_blk_num - blks, STp->logical_blk_num - 1);
3287#endif
3288	osst_init_aux(STp, OS_FRAME_TYPE_DATA, STp->frame_seq_number++,
3289		      STp->logical_blk_num - blks, STp->block_size, blks);
3290
3291#if DEBUG
3292	if (!synchronous)
3293		STp->write_pending = 1;
3294#endif
3295	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE, STp->timeout,
3296									MAX_RETRIES, synchronous);
3297	if (!SRpnt)
3298		return (-EBUSY);
3299	*aSRpnt = SRpnt;
3300
3301	if (synchronous) {
3302		if (STp->buffer->syscall_result != 0) {
3303#if DEBUG
3304			if (debugging)
3305				printk(OSST_DEB_MSG "%s:D: Error on write:\n", name);
3306#endif
3307			if ((SRpnt->sense[0] & 0x70) == 0x70 &&
3308			    (SRpnt->sense[2] & 0x40)) {
3309				if ((SRpnt->sense[2] & 0x0f) == VOLUME_OVERFLOW)
3310					return (-ENOSPC);
3311			}
3312			else {
3313				if (osst_write_error_recovery(STp, aSRpnt, 1))
3314					return (-EIO);
3315			}
3316		}
3317		else
3318			STp->first_frame_position++;
3319	}
3320
3321	STp->write_count++;
3322
3323	return 0;
3324}
3325
3326/* Lock or unlock the drive door. Don't use when struct osst_request allocated. */
3327static int do_door_lock(struct osst_tape * STp, int do_lock)
3328{
3329	int retval, cmd;
3330
3331	cmd = do_lock ? SCSI_IOCTL_DOORLOCK : SCSI_IOCTL_DOORUNLOCK;
3332#if DEBUG
3333	printk(OSST_DEB_MSG "%s:D: %socking drive door.\n", tape_name(STp), do_lock ? "L" : "Unl");
3334#endif
3335	retval = scsi_ioctl(STp->device, cmd, NULL);
3336	if (!retval) {
 
 
3337		STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
3338	}
3339	else {
3340		STp->door_locked = ST_LOCK_FAILS;
3341	}
3342	return retval;
3343}
3344
3345/* Set the internal state after reset */
3346static void reset_state(struct osst_tape *STp)
3347{
3348	int i;
3349	struct st_partstat *STps;
3350
3351	STp->pos_unknown = 0;
3352	for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3353		STps = &(STp->ps[i]);
3354		STps->rw = ST_IDLE;
3355		STps->eof = ST_NOEOF;
3356		STps->at_sm = 0;
3357		STps->last_block_valid = 0;
3358		STps->drv_block = -1;
3359		STps->drv_file = -1;
3360	}
3361}
3362				
3363
3364/* Entry points to osst */
3365
3366/* Write command */
3367static ssize_t osst_write(struct file * filp, const char __user * buf, size_t count, loff_t *ppos)
3368{
3369	ssize_t		      total, retval = 0;
3370	ssize_t		      i, do_count, blks, transfer;
3371	int		      write_threshold;
3372	int		      doing_write = 0;
3373	const char   __user * b_point;
3374	struct osst_request * SRpnt = NULL;
3375	struct st_modedef   * STm;
3376	struct st_partstat  * STps;
3377	struct osst_tape    * STp  = filp->private_data;
3378	char		    * name = tape_name(STp);
3379
3380
3381	if (mutex_lock_interruptible(&STp->lock))
3382		return (-ERESTARTSYS);
3383
3384	/*
3385	 * If we are in the middle of error recovery, don't let anyone
3386	 * else try and use this device.  Also, if error recovery fails, it
3387	 * may try and take the device offline, in which case all further
3388	 * access to the device is prohibited.
3389	 */
3390	if( !scsi_block_when_processing_errors(STp->device) ) {
3391		retval = (-ENXIO);
3392		goto out;
3393	}
3394	
3395	if (STp->ready != ST_READY) {
3396		if (STp->ready == ST_NO_TAPE)
3397			retval = (-ENOMEDIUM);
3398		else
3399			retval = (-EIO);
3400		goto out;
3401	}
3402	STm = &(STp->modes[STp->current_mode]);
3403	if (!STm->defined) {
3404		retval = (-ENXIO);
3405		goto out;
3406	}
3407	if (count == 0)
3408		goto out;
3409
3410	/*
3411	 * If there was a bus reset, block further access
3412	 * to this device.
3413	 */
3414	if (STp->pos_unknown) {
3415		retval = (-EIO);
3416		goto out;
3417	}
3418
3419#if DEBUG
3420	if (!STp->in_use) {
3421		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
3422		retval = (-EIO);
3423		goto out;
3424	}
3425#endif
3426
3427	if (STp->write_prot) {
3428		retval = (-EACCES);
3429		goto out;
3430	}
3431
3432	/* Write must be integral number of blocks */
3433	if (STp->block_size != 0 && (count % STp->block_size) != 0) {
3434		printk(KERN_ERR "%s:E: Write (%Zd bytes) not multiple of tape block size (%d%c).\n",
3435				       name, count, STp->block_size<1024?
3436				       STp->block_size:STp->block_size/1024, STp->block_size<1024?'b':'k');
3437		retval = (-EINVAL);
3438		goto out;
3439	}
3440
3441	if (STp->first_frame_position >= STp->capacity - OSST_EOM_RESERVE) {
3442		printk(KERN_ERR "%s:E: Write truncated at EOM early warning (frame %d).\n",
3443				       name, STp->first_frame_position);
3444		retval = (-ENOSPC);
3445		goto out;
3446	}
3447
3448	if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED && !do_door_lock(STp, 1))
3449		STp->door_locked = ST_LOCKED_AUTO;
3450
3451	STps = &(STp->ps[STp->partition]);
3452
3453	if (STps->rw == ST_READING) {
3454#if DEBUG
3455		printk(OSST_DEB_MSG "%s:D: Switching from read to write at file %d, block %d\n", name, 
3456					STps->drv_file, STps->drv_block);
3457#endif
3458		retval = osst_flush_buffer(STp, &SRpnt, 0);
3459		if (retval)
3460			goto out;
3461		STps->rw = ST_IDLE;
3462	}
3463	if (STps->rw != ST_WRITING) {
3464		/* Are we totally rewriting this tape? */
3465		if (!STp->header_ok ||
3466		    (STp->first_frame_position == STp->first_data_ppos && STps->drv_block < 0) ||
3467		    (STps->drv_file == 0 && STps->drv_block == 0)) {
3468			STp->wrt_pass_cntr++;
3469#if DEBUG
3470			printk(OSST_DEB_MSG "%s:D: Allocating next write pass counter: %d\n",
3471						  name, STp->wrt_pass_cntr);
3472#endif
3473			osst_reset_header(STp, &SRpnt);
3474			STps->drv_file = STps->drv_block = 0;
3475		}
3476		/* Do we know where we'll be writing on the tape? */
3477		else {
3478			if ((STp->fast_open && osst_verify_position(STp, &SRpnt)) ||
3479			  		STps->drv_file < 0 || STps->drv_block < 0) {
3480				if (STp->first_frame_position == STp->eod_frame_ppos) {	/* at EOD */
3481			  		STps->drv_file = STp->filemark_cnt;
3482			  		STps->drv_block = 0;
3483				}
3484				else {
3485					/* We have no idea where the tape is positioned - give up */
3486#if DEBUG
3487					printk(OSST_DEB_MSG
3488						"%s:D: Cannot write at indeterminate position.\n", name);
3489#endif
3490					retval = (-EIO);
3491					goto out;
3492				}
3493      			}	  
3494			if ((STps->drv_file + STps->drv_block) > 0 && STps->drv_file < STp->filemark_cnt) {
3495				STp->filemark_cnt = STps->drv_file;
3496				STp->last_mark_ppos =
3497				       	ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[STp->filemark_cnt-1]);
3498				printk(KERN_WARNING
3499					"%s:W: Overwriting file %d with old write pass counter %d\n",
3500						name, STps->drv_file, STp->wrt_pass_cntr);
3501				printk(KERN_WARNING
3502					"%s:W: may lead to stale data being accepted on reading back!\n",
3503						name);
3504#if DEBUG
3505				printk(OSST_DEB_MSG
3506				  "%s:D: resetting filemark count to %d and last mark ppos,lbn to %d,%d\n",
3507					name, STp->filemark_cnt, STp->last_mark_ppos, STp->last_mark_lbn);
3508#endif
3509			}
3510		}
3511		STp->fast_open = 0;
3512	}
3513	if (!STp->header_ok) {
3514#if DEBUG
3515		printk(OSST_DEB_MSG "%s:D: Write cannot proceed without valid headers\n", name);
3516#endif
3517		retval = (-EIO);
3518		goto out;
3519	}
3520
3521	if ((STp->buffer)->writing) {
3522if (SRpnt) printk(KERN_ERR "%s:A: Not supposed to have SRpnt at line %d\n", name, __LINE__);
3523		osst_write_behind_check(STp);
3524		if ((STp->buffer)->syscall_result) {
3525#if DEBUG
3526		if (debugging)
3527			printk(OSST_DEB_MSG "%s:D: Async write error (write) %x.\n", name,
3528						 (STp->buffer)->midlevel_result);
3529#endif
3530		if ((STp->buffer)->midlevel_result == INT_MAX)
3531			STps->eof = ST_EOM_OK;
3532		else
3533			STps->eof = ST_EOM_ERROR;
3534		}
3535	}
3536	if (STps->eof == ST_EOM_OK) {
3537		retval = (-ENOSPC);
3538		goto out;
3539	}
3540	else if (STps->eof == ST_EOM_ERROR) {
3541		retval = (-EIO);
3542		goto out;
3543	}
3544
3545	/* Check the buffer readability in cases where copy_user might catch
3546		 the problems after some tape movement. */
3547	if ((copy_from_user(&i, buf, 1) != 0 ||
3548	     copy_from_user(&i, buf + count - 1, 1) != 0)) {
3549		retval = (-EFAULT);
3550		goto out;
3551	}
3552
3553	if (!STm->do_buffer_writes) {
3554		write_threshold = 1;
3555	}
3556	else
3557		write_threshold = (STp->buffer)->buffer_blocks * STp->block_size;
3558	if (!STm->do_async_writes)
3559		write_threshold--;
3560
3561	total = count;
3562#if DEBUG
3563	if (debugging)
3564		printk(OSST_DEB_MSG "%s:D: Writing %d bytes to file %d block %d lblk %d fseq %d fppos %d\n",
3565				name, (int) count, STps->drv_file, STps->drv_block,
3566				STp->logical_blk_num, STp->frame_seq_number, STp->first_frame_position);
3567#endif
3568	b_point = buf;
3569	while ((STp->buffer)->buffer_bytes + count > write_threshold)
3570	{
3571		doing_write = 1;
3572		do_count = (STp->buffer)->buffer_blocks * STp->block_size -
3573			   (STp->buffer)->buffer_bytes;
3574		if (do_count > count)
3575			do_count = count;
3576
3577		i = append_to_buffer(b_point, STp->buffer, do_count);
3578		if (i) {
3579			retval = i;
3580			goto out;
3581		}
3582
3583		blks = do_count / STp->block_size;
3584		STp->logical_blk_num += blks;  /* logical_blk_num is incremented as data is moved from user */
3585  
3586		i = osst_write_frame(STp, &SRpnt, 1);
3587
3588		if (i == (-ENOSPC)) {
3589			transfer = STp->buffer->writing;	/* FIXME -- check this logic */
3590			if (transfer <= do_count) {
3591				*ppos += do_count - transfer;
3592				count -= do_count - transfer;
3593				if (STps->drv_block >= 0) {
3594					STps->drv_block += (do_count - transfer) / STp->block_size;
3595				}
3596				STps->eof = ST_EOM_OK;
3597				retval = (-ENOSPC);		/* EOM within current request */
3598#if DEBUG
3599				if (debugging)
3600				      printk(OSST_DEB_MSG "%s:D: EOM with %d bytes unwritten.\n",
3601							     name, (int) transfer);
3602#endif
3603			}
3604			else {
3605				STps->eof = ST_EOM_ERROR;
3606				STps->drv_block = (-1);		/* Too cautious? */
3607				retval = (-EIO);		/* EOM for old data */
3608#if DEBUG
3609				if (debugging)
3610				      printk(OSST_DEB_MSG "%s:D: EOM with lost data.\n", name);
3611#endif
3612			}
3613		}
3614		else
3615			retval = i;
3616			
3617		if (retval < 0) {
3618			if (SRpnt != NULL) {
3619				osst_release_request(SRpnt);
3620				SRpnt = NULL;
3621			}
3622			STp->buffer->buffer_bytes = 0;
3623			STp->dirty = 0;
3624			if (count < total)
3625				retval = total - count;
3626			goto out;
3627		}
3628
3629		*ppos += do_count;
3630		b_point += do_count;
3631		count -= do_count;
3632		if (STps->drv_block >= 0) {
3633			STps->drv_block += blks;
3634		}
3635		STp->buffer->buffer_bytes = 0;
3636		STp->dirty = 0;
3637	}  /* end while write threshold exceeded */
3638
3639	if (count != 0) {
3640		STp->dirty = 1;
3641		i = append_to_buffer(b_point, STp->buffer, count);
3642		if (i) {
3643			retval = i;
3644			goto out;
3645		}
3646		blks = count / STp->block_size;
3647		STp->logical_blk_num += blks;
3648		if (STps->drv_block >= 0) {
3649			STps->drv_block += blks;
3650		}
3651		*ppos += count;
3652		count = 0;
3653	}
3654
3655	if (doing_write && (STp->buffer)->syscall_result != 0) {
3656		retval = (STp->buffer)->syscall_result;
3657		goto out;
3658	}
3659
3660	if (STm->do_async_writes && ((STp->buffer)->buffer_bytes >= STp->write_threshold)) { 
3661		/* Schedule an asynchronous write */
3662		(STp->buffer)->writing = ((STp->buffer)->buffer_bytes /
3663					   STp->block_size) * STp->block_size;
3664		STp->dirty = !((STp->buffer)->writing ==
3665				          (STp->buffer)->buffer_bytes);
3666
3667		i = osst_write_frame(STp, &SRpnt, 0);
3668		if (i < 0) {
3669			retval = (-EIO);
3670			goto out;
3671		}
3672		SRpnt = NULL;			/* Prevent releasing this request! */
3673	}
3674	STps->at_sm &= (total == 0);
3675	if (total > 0)
3676		STps->eof = ST_NOEOF;
3677
3678	retval = total;
3679
3680out:
3681	if (SRpnt != NULL) osst_release_request(SRpnt);
3682
3683	mutex_unlock(&STp->lock);
3684
3685	return retval;
3686}
3687
3688
3689/* Read command */
3690static ssize_t osst_read(struct file * filp, char __user * buf, size_t count, loff_t *ppos)
3691{
3692	ssize_t		      total, retval = 0;
3693	ssize_t		      i, transfer;
3694	int		      special;
3695	struct st_modedef   * STm;
3696	struct st_partstat  * STps;
3697	struct osst_request * SRpnt = NULL;
3698	struct osst_tape    * STp   = filp->private_data;
3699	char		    * name  = tape_name(STp);
3700
3701
3702	if (mutex_lock_interruptible(&STp->lock))
3703		return (-ERESTARTSYS);
3704
3705	/*
3706	 * If we are in the middle of error recovery, don't let anyone
3707	 * else try and use this device.  Also, if error recovery fails, it
3708	 * may try and take the device offline, in which case all further
3709	 * access to the device is prohibited.
3710	 */
3711	if( !scsi_block_when_processing_errors(STp->device) ) {
3712		retval = (-ENXIO);
3713		goto out;
3714	}
3715	
3716	if (STp->ready != ST_READY) {
3717		if (STp->ready == ST_NO_TAPE)
3718			retval = (-ENOMEDIUM);
3719		else
3720			retval = (-EIO);
3721		goto out;
3722	}
3723	STm = &(STp->modes[STp->current_mode]);
3724	if (!STm->defined) {
3725		retval = (-ENXIO);
3726		goto out;
3727	}
3728#if DEBUG
3729	if (!STp->in_use) {
3730		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
3731		retval = (-EIO);
3732		goto out;
3733	}
3734#endif
3735	/* Must have initialized medium */
3736	if (!STp->header_ok) {
3737		retval = (-EIO);
3738		goto out;
3739	}
3740
3741	if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED && !do_door_lock(STp, 1))
3742		STp->door_locked = ST_LOCKED_AUTO;
3743
3744	STps = &(STp->ps[STp->partition]);
3745	if (STps->rw == ST_WRITING) {
3746		retval = osst_flush_buffer(STp, &SRpnt, 0);
3747		if (retval)
3748			goto out;
3749		STps->rw = ST_IDLE;
3750		/* FIXME -- this may leave the tape without EOD and up2date headers */
3751	}
3752
3753	if ((count % STp->block_size) != 0) {
3754		printk(KERN_WARNING
3755		    "%s:W: Read (%Zd bytes) not multiple of tape block size (%d%c).\n", name, count,
3756		    STp->block_size<1024?STp->block_size:STp->block_size/1024, STp->block_size<1024?'b':'k');
3757	}
3758
3759#if DEBUG
3760	if (debugging && STps->eof != ST_NOEOF)
3761		printk(OSST_DEB_MSG "%s:D: EOF/EOM flag up (%d). Bytes %d\n", name,
3762				     STps->eof, (STp->buffer)->buffer_bytes);
3763#endif
3764	if ((STp->buffer)->buffer_bytes == 0 &&
3765	     STps->eof >= ST_EOD_1) {
3766		if (STps->eof < ST_EOD) {
3767			STps->eof += 1;
3768			retval = 0;
3769			goto out;
3770		}
3771		retval = (-EIO);  /* EOM or Blank Check */
3772		goto out;
3773	}
3774
3775	/* Check the buffer writability before any tape movement. Don't alter
3776		 buffer data. */
3777	if (copy_from_user(&i, buf, 1)             != 0 ||
3778	    copy_to_user  (buf, &i, 1)             != 0 ||
3779	    copy_from_user(&i, buf + count - 1, 1) != 0 ||
3780	    copy_to_user  (buf + count - 1, &i, 1) != 0) {
3781		retval = (-EFAULT);
3782		goto out;
3783	}
3784
3785	/* Loop until enough data in buffer or a special condition found */
3786	for (total = 0, special = 0; total < count - STp->block_size + 1 && !special; ) {
3787
3788		/* Get new data if the buffer is empty */
3789		if ((STp->buffer)->buffer_bytes == 0) {
3790			if (STps->eof == ST_FM_HIT)
3791				break;
3792			special = osst_get_logical_frame(STp, &SRpnt, STp->frame_seq_number, 0);
3793			if (special < 0) { 			/* No need to continue read */
3794				STp->frame_in_buffer = 0;
3795				retval = special;
3796				goto out;
3797			}
3798		}
3799
3800		/* Move the data from driver buffer to user buffer */
3801		if ((STp->buffer)->buffer_bytes > 0) {
3802#if DEBUG
3803			if (debugging && STps->eof != ST_NOEOF)
3804			    printk(OSST_DEB_MSG "%s:D: EOF up (%d). Left %d, needed %d.\n", name,
3805						 STps->eof, (STp->buffer)->buffer_bytes, (int) (count - total));
3806#endif
3807		       	/* force multiple of block size, note block_size may have been adjusted */
3808			transfer = (((STp->buffer)->buffer_bytes < count - total ?
3809				     (STp->buffer)->buffer_bytes : count - total)/
3810					STp->block_size) * STp->block_size;
3811
3812			if (transfer == 0) {
3813				printk(KERN_WARNING
3814				  "%s:W: Nothing can be transferred, requested %Zd, tape block size (%d%c).\n",
3815			   		name, count, STp->block_size < 1024?
3816					STp->block_size:STp->block_size/1024,
3817				       	STp->block_size<1024?'b':'k');
3818				break;
3819			}
3820			i = from_buffer(STp->buffer, buf, transfer);
3821			if (i)  {
3822				retval = i;
3823				goto out;
3824			}
3825			STp->logical_blk_num += transfer / STp->block_size;
3826			STps->drv_block      += transfer / STp->block_size;
3827			*ppos          += transfer;
3828			buf                  += transfer;
3829			total                += transfer;
3830		}
3831 
3832		if ((STp->buffer)->buffer_bytes == 0) {
3833#if DEBUG
3834			if (debugging)
3835				printk(OSST_DEB_MSG "%s:D: Finished with frame %d\n",
3836					       	name, STp->frame_seq_number);
3837#endif
3838			STp->frame_in_buffer = 0;
3839			STp->frame_seq_number++;              /* frame to look for next time */
3840		}
3841	} /* for (total = 0, special = 0; total < count && !special; ) */
3842
3843	/* Change the eof state if no data from tape or buffer */
3844	if (total == 0) {
3845		if (STps->eof == ST_FM_HIT) {
3846			STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD_2:ST_FM;
3847			STps->drv_block = 0;
3848			if (STps->drv_file >= 0)
3849				STps->drv_file++;
3850		}
3851		else if (STps->eof == ST_EOD_1) {
3852			STps->eof = ST_EOD_2;
3853			if (STps->drv_block > 0 && STps->drv_file >= 0)
3854				STps->drv_file++;
3855			STps->drv_block = 0;
3856		}
3857		else if (STps->eof == ST_EOD_2)
3858			STps->eof = ST_EOD;
3859	}
3860	else if (STps->eof == ST_FM)
3861		STps->eof = ST_NOEOF;
3862
3863	retval = total;
3864
3865out:
3866	if (SRpnt != NULL) osst_release_request(SRpnt);
3867
3868	mutex_unlock(&STp->lock);
3869
3870	return retval;
3871}
3872
3873
3874/* Set the driver options */
3875static void osst_log_options(struct osst_tape *STp, struct st_modedef *STm, char *name)
3876{
3877  printk(KERN_INFO
3878"%s:I: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
3879	 name, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
3880	 STm->do_read_ahead);
3881  printk(KERN_INFO
3882"%s:I:    can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
3883	 name, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
3884  printk(KERN_INFO
3885"%s:I:    defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
3886	 name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
3887	 STp->scsi2_logical);
3888  printk(KERN_INFO
3889"%s:I:    sysv: %d\n", name, STm->sysv);
3890#if DEBUG
3891  printk(KERN_INFO
3892	 "%s:D:    debugging: %d\n",
3893	 name, debugging);
3894#endif
3895}
3896
3897
3898static int osst_set_options(struct osst_tape *STp, long options)
3899{
3900	int		    value;
3901	long		    code;
3902	struct st_modedef * STm;
3903	char		  * name = tape_name(STp);
3904
3905	STm = &(STp->modes[STp->current_mode]);
3906	if (!STm->defined) {
3907		memcpy(STm, &(STp->modes[0]), sizeof(*STm));
3908		modes_defined = 1;
3909#if DEBUG
3910		if (debugging)
3911			printk(OSST_DEB_MSG "%s:D: Initialized mode %d definition from mode 0\n",
3912					     name, STp->current_mode);
3913#endif
3914	}
3915
3916	code = options & MT_ST_OPTIONS;
3917	if (code == MT_ST_BOOLEANS) {
3918		STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
3919		STm->do_async_writes  = (options & MT_ST_ASYNC_WRITES) != 0;
3920		STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
3921		STm->do_read_ahead    = (options & MT_ST_READ_AHEAD) != 0;
3922		STp->two_fm	      = (options & MT_ST_TWO_FM) != 0;
3923		STp->fast_mteom	      = (options & MT_ST_FAST_MTEOM) != 0;
3924		STp->do_auto_lock     = (options & MT_ST_AUTO_LOCK) != 0;
3925		STp->can_bsr          = (options & MT_ST_CAN_BSR) != 0;
3926		STp->omit_blklims     = (options & MT_ST_NO_BLKLIMS) != 0;
3927		if ((STp->device)->scsi_level >= SCSI_2)
3928			STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
3929		STp->scsi2_logical    = (options & MT_ST_SCSI2LOGICAL) != 0;
3930		STm->sysv	      = (options & MT_ST_SYSV) != 0;
3931#if DEBUG
3932		debugging = (options & MT_ST_DEBUGGING) != 0;
3933#endif
3934		osst_log_options(STp, STm, name);
3935	}
3936	else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
3937		value = (code == MT_ST_SETBOOLEANS);
3938		if ((options & MT_ST_BUFFER_WRITES) != 0)
3939			STm->do_buffer_writes = value;
3940		if ((options & MT_ST_ASYNC_WRITES) != 0)
3941			STm->do_async_writes = value;
3942		if ((options & MT_ST_DEF_WRITES) != 0)
3943			STm->defaults_for_writes = value;
3944		if ((options & MT_ST_READ_AHEAD) != 0)
3945			STm->do_read_ahead = value;
3946		if ((options & MT_ST_TWO_FM) != 0)
3947			STp->two_fm = value;
3948		if ((options & MT_ST_FAST_MTEOM) != 0)
3949			STp->fast_mteom = value;
3950		if ((options & MT_ST_AUTO_LOCK) != 0)
3951			STp->do_auto_lock = value;
3952		if ((options & MT_ST_CAN_BSR) != 0)
3953			STp->can_bsr = value;
3954		if ((options & MT_ST_NO_BLKLIMS) != 0)
3955			STp->omit_blklims = value;
3956		if ((STp->device)->scsi_level >= SCSI_2 &&
3957		    (options & MT_ST_CAN_PARTITIONS) != 0)
3958			STp->can_partitions = value;
3959		if ((options & MT_ST_SCSI2LOGICAL) != 0)
3960			STp->scsi2_logical = value;
3961		if ((options & MT_ST_SYSV) != 0)
3962			STm->sysv = value;
3963#if DEBUG
3964		if ((options & MT_ST_DEBUGGING) != 0)
3965			debugging = value;
3966#endif
3967		osst_log_options(STp, STm, name);
3968	}
3969	else if (code == MT_ST_WRITE_THRESHOLD) {
3970		value = (options & ~MT_ST_OPTIONS) * ST_KILOBYTE;
3971		if (value < 1 || value > osst_buffer_size) {
3972			printk(KERN_WARNING "%s:W: Write threshold %d too small or too large.\n",
3973					     name, value);
3974			return (-EIO);
3975		}
3976		STp->write_threshold = value;
3977		printk(KERN_INFO "%s:I: Write threshold set to %d bytes.\n",
3978				  name, value);
3979	}
3980	else if (code == MT_ST_DEF_BLKSIZE) {
3981		value = (options & ~MT_ST_OPTIONS);
3982		if (value == ~MT_ST_OPTIONS) {
3983			STm->default_blksize = (-1);
3984			printk(KERN_INFO "%s:I: Default block size disabled.\n", name);
3985		}
3986		else {
3987			if (value < 512 || value > OS_DATA_SIZE || OS_DATA_SIZE % value) {
3988				printk(KERN_WARNING "%s:W: Default block size cannot be set to %d.\n",
3989							 name, value);
3990				return (-EINVAL);
3991			}
3992			STm->default_blksize = value;
3993			printk(KERN_INFO "%s:I: Default block size set to %d bytes.\n",
3994					  name, STm->default_blksize);
3995		}
3996	}
3997	else if (code == MT_ST_TIMEOUTS) {
3998		value = (options & ~MT_ST_OPTIONS);
3999		if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
4000			STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
4001			printk(KERN_INFO "%s:I: Long timeout set to %d seconds.\n", name,
4002					     (value & ~MT_ST_SET_LONG_TIMEOUT));
4003		}
4004		else {
4005			STp->timeout = value * HZ;
4006			printk(KERN_INFO "%s:I: Normal timeout set to %d seconds.\n", name, value);
4007		}
4008	}
4009	else if (code == MT_ST_DEF_OPTIONS) {
4010		code = (options & ~MT_ST_CLEAR_DEFAULT);
4011		value = (options & MT_ST_CLEAR_DEFAULT);
4012		if (code == MT_ST_DEF_DENSITY) {
4013			if (value == MT_ST_CLEAR_DEFAULT) {
4014				STm->default_density = (-1);
4015				printk(KERN_INFO "%s:I: Density default disabled.\n", name);
4016			}
4017			else {
4018				STm->default_density = value & 0xff;
4019				printk(KERN_INFO "%s:I: Density default set to %x\n",
4020						  name, STm->default_density);
4021			}
4022		}
4023		else if (code == MT_ST_DEF_DRVBUFFER) {
4024			if (value == MT_ST_CLEAR_DEFAULT) {
4025				STp->default_drvbuffer = 0xff;
4026				printk(KERN_INFO "%s:I: Drive buffer default disabled.\n", name);
4027			}
4028			else {
4029				STp->default_drvbuffer = value & 7;
4030				printk(KERN_INFO "%s:I: Drive buffer default set to %x\n",
4031						  name, STp->default_drvbuffer);
4032			}
4033		}
4034		else if (code == MT_ST_DEF_COMPRESSION) {
4035			if (value == MT_ST_CLEAR_DEFAULT) {
4036				STm->default_compression = ST_DONT_TOUCH;
4037				printk(KERN_INFO "%s:I: Compression default disabled.\n", name);
4038			}
4039			else {
4040				STm->default_compression = (value & 1 ? ST_YES : ST_NO);
4041				printk(KERN_INFO "%s:I: Compression default set to %x\n",
4042						  name, (value & 1));
4043			}
4044		}
4045	}
4046	else
4047		return (-EIO);
4048
4049	return 0;
4050}
4051
4052
4053/* Internal ioctl function */
4054static int osst_int_ioctl(struct osst_tape * STp, struct osst_request ** aSRpnt,
4055			     unsigned int cmd_in, unsigned long arg)
4056{
4057	int			timeout;
4058	long			ltmp;
4059	int			i, ioctl_result;
4060	int			chg_eof = 1;
4061	unsigned char		cmd[MAX_COMMAND_SIZE];
4062	struct osst_request   * SRpnt = * aSRpnt;
4063	struct st_partstat    * STps;
4064	int			fileno, blkno, at_sm, frame_seq_numbr, logical_blk_num;
4065	int			datalen = 0, direction = DMA_NONE;
4066	char		      * name = tape_name(STp);
4067
4068	if (STp->ready != ST_READY && cmd_in != MTLOAD) {
4069		if (STp->ready == ST_NO_TAPE)
4070			return (-ENOMEDIUM);
4071		else
4072			return (-EIO);
4073	}
4074	timeout = STp->long_timeout;
4075	STps = &(STp->ps[STp->partition]);
4076	fileno = STps->drv_file;
4077	blkno = STps->drv_block;
4078	at_sm = STps->at_sm;
4079	frame_seq_numbr = STp->frame_seq_number;
4080	logical_blk_num = STp->logical_blk_num;
4081
4082	memset(cmd, 0, MAX_COMMAND_SIZE);
4083	switch (cmd_in) {
4084	 case MTFSFM:
4085		chg_eof = 0; /* Changed from the FSF after this */
4086	 case MTFSF:
4087		if (STp->raw)
4088		   return (-EIO);
4089		if (STp->linux_media)
4090		   ioctl_result = osst_space_over_filemarks_forward_fast(STp, &SRpnt, cmd_in, arg);
4091		else
4092		   ioctl_result = osst_space_over_filemarks_forward_slow(STp, &SRpnt, cmd_in, arg);
4093		if (fileno >= 0)
4094		   fileno += arg;
4095		blkno = 0;
4096		at_sm &= (arg == 0);
4097		goto os_bypass;
4098
4099	 case MTBSF:
4100		chg_eof = 0; /* Changed from the FSF after this */
4101	 case MTBSFM:
4102		if (STp->raw)
4103		   return (-EIO);
4104		ioctl_result = osst_space_over_filemarks_backward(STp, &SRpnt, cmd_in, arg);
4105		if (fileno >= 0)
4106		   fileno -= arg;
4107		blkno = (-1);  /* We can't know the block number */
4108		at_sm &= (arg == 0);
4109		goto os_bypass;
4110
4111	 case MTFSR:
4112	 case MTBSR:
4113#if DEBUG
4114		if (debugging)
4115		   printk(OSST_DEB_MSG "%s:D: Skipping %lu blocks %s from logical block %d\n",
4116				name, arg, cmd_in==MTFSR?"forward":"backward", logical_blk_num);
4117#endif
4118		if (cmd_in == MTFSR) {
4119		   logical_blk_num += arg;
4120		   if (blkno >= 0) blkno += arg;
4121		}
4122		else {
4123		   logical_blk_num -= arg;
4124		   if (blkno >= 0) blkno -= arg;
4125		}
4126		ioctl_result = osst_seek_logical_blk(STp, &SRpnt, logical_blk_num);
4127		fileno = STps->drv_file;
4128		blkno  = STps->drv_block;
4129		at_sm &= (arg == 0);
4130		goto os_bypass;
4131
4132	 case MTFSS:
4133		cmd[0] = SPACE;
4134		cmd[1] = 0x04; /* Space Setmarks */   /* FIXME -- OS can't do this? */
4135		cmd[2] = (arg >> 16);
4136		cmd[3] = (arg >> 8);
4137		cmd[4] = arg;
4138#if DEBUG
4139		if (debugging)
4140			printk(OSST_DEB_MSG "%s:D: Spacing tape forward %d setmarks.\n", name,
4141		cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
4142#endif
4143		if (arg != 0) {
4144			blkno = fileno = (-1);
4145			at_sm = 1;
4146		}
4147		break;
4148	 case MTBSS:
4149		cmd[0] = SPACE;
4150		cmd[1] = 0x04; /* Space Setmarks */   /* FIXME -- OS can't do this? */
4151		ltmp = (-arg);
4152		cmd[2] = (ltmp >> 16);
4153		cmd[3] = (ltmp >> 8);
4154		cmd[4] = ltmp;
4155#if DEBUG
4156		if (debugging) {
4157			if (cmd[2] & 0x80)
4158			   ltmp = 0xff000000;
4159			ltmp = ltmp | (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
4160			printk(OSST_DEB_MSG "%s:D: Spacing tape backward %ld setmarks.\n",
4161						name, (-ltmp));
4162		 }
4163#endif
4164		 if (arg != 0) {
4165			blkno = fileno = (-1);
4166			at_sm = 1;
4167		 }
4168		 break;
4169	 case MTWEOF:
4170		 if ((STps->rw == ST_WRITING || STp->dirty) && !STp->pos_unknown) {
4171			STp->write_type = OS_WRITE_DATA;
4172			ioctl_result = osst_flush_write_buffer(STp, &SRpnt);
4173		 } else
4174			ioctl_result = 0;
4175#if DEBUG
4176		 if (debugging) 
4177			   printk(OSST_DEB_MSG "%s:D: Writing %ld filemark(s).\n", name, arg);
4178#endif
4179		 for (i=0; i<arg; i++)
4180			ioctl_result |= osst_write_filemark(STp, &SRpnt);
4181		 if (fileno >= 0) fileno += arg;
4182		 if (blkno  >= 0) blkno   = 0;
4183		 goto os_bypass;
4184
4185	 case MTWSM:
4186		 if (STp->write_prot)
4187			return (-EACCES);
4188		 if (!STp->raw)
4189			return 0;
4190		 cmd[0] = WRITE_FILEMARKS;   /* FIXME -- need OS version */
4191		 if (cmd_in == MTWSM)
4192			 cmd[1] = 2;
4193		 cmd[2] = (arg >> 16);
4194		 cmd[3] = (arg >> 8);
4195		 cmd[4] = arg;
4196		 timeout = STp->timeout;
4197#if DEBUG
4198		 if (debugging) 
4199			   printk(OSST_DEB_MSG "%s:D: Writing %d setmark(s).\n", name,
4200				  cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
4201#endif
4202		 if (fileno >= 0)
4203			fileno += arg;
4204		 blkno = 0;
4205		 at_sm = (cmd_in == MTWSM);
4206		 break;
4207	 case MTOFFL:
4208	 case MTLOAD:
4209	 case MTUNLOAD:
4210	 case MTRETEN:
4211		 cmd[0] = START_STOP;
4212		 cmd[1] = 1;			/* Don't wait for completion */
4213		 if (cmd_in == MTLOAD) {
4214		     if (STp->ready == ST_NO_TAPE)
4215			 cmd[4] = 4;		/* open tray */
4216		      else
4217			 cmd[4] = 1;		/* load */
4218		 }
4219		 if (cmd_in == MTRETEN)
4220			 cmd[4] = 3;		/* retension then mount */
4221		 if (cmd_in == MTOFFL)
4222			 cmd[4] = 4;		/* rewind then eject */
4223		 timeout = STp->timeout;
4224#if DEBUG
4225		 if (debugging) {
4226			 switch (cmd_in) {
4227				 case MTUNLOAD:
4228					 printk(OSST_DEB_MSG "%s:D: Unloading tape.\n", name);
4229					 break;
4230				 case MTLOAD:
4231					 printk(OSST_DEB_MSG "%s:D: Loading tape.\n", name);
4232					 break;
4233				 case MTRETEN:
4234					 printk(OSST_DEB_MSG "%s:D: Retensioning tape.\n", name);
4235					 break;
4236				 case MTOFFL:
4237					 printk(OSST_DEB_MSG "%s:D: Ejecting tape.\n", name);
4238					 break;
4239			 }
4240		 }
4241#endif
4242       fileno = blkno = at_sm = frame_seq_numbr = logical_blk_num = 0 ;
4243		 break;
4244	 case MTNOP:
4245#if DEBUG
4246		 if (debugging)
4247			 printk(OSST_DEB_MSG "%s:D: No-op on tape.\n", name);
4248#endif
4249		 return 0;  /* Should do something ? */
4250		 break;
4251	 case MTEOM:
4252#if DEBUG
4253		if (debugging)
4254		   printk(OSST_DEB_MSG "%s:D: Spacing to end of recorded medium.\n", name);
4255#endif
4256		if ((osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos) < 0) ||
4257			    (osst_get_logical_frame(STp, &SRpnt, -1, 0)               < 0)) {
4258		   ioctl_result = -EIO;
4259		   goto os_bypass;
4260		}
4261		if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_EOD) {
4262#if DEBUG
4263		   printk(OSST_DEB_MSG "%s:D: No EOD frame found where expected.\n", name);
4264#endif
4265		   ioctl_result = -EIO;
4266		   goto os_bypass;
4267		}
4268		ioctl_result = osst_set_frame_position(STp, &SRpnt, STp->eod_frame_ppos, 0);
4269		fileno = STp->filemark_cnt;
4270		blkno  = at_sm = 0;
4271		goto os_bypass;
4272
4273	 case MTERASE:
4274		if (STp->write_prot)
4275		   return (-EACCES);
4276		ioctl_result = osst_reset_header(STp, &SRpnt);
4277		i = osst_write_eod(STp, &SRpnt);
4278		if (i < ioctl_result) ioctl_result = i;
4279		i = osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos);
4280		if (i < ioctl_result) ioctl_result = i;
4281		fileno = blkno = at_sm = 0 ;
4282		goto os_bypass;
4283
4284	 case MTREW:
4285		cmd[0] = REZERO_UNIT; /* rewind */
4286		cmd[1] = 1;
4287#if DEBUG
4288		if (debugging)
4289		   printk(OSST_DEB_MSG "%s:D: Rewinding tape, Immed=%d.\n", name, cmd[1]);
4290#endif
4291		fileno = blkno = at_sm = frame_seq_numbr = logical_blk_num = 0 ;
4292		break;
4293
4294	 case MTSETBLK:           /* Set block length */
4295		 if ((STps->drv_block == 0 )			  &&
4296		     !STp->dirty				  &&
4297		     ((STp->buffer)->buffer_bytes == 0)		  &&
4298		     ((arg & MT_ST_BLKSIZE_MASK) >= 512 )	  && 
4299		     ((arg & MT_ST_BLKSIZE_MASK) <= OS_DATA_SIZE) &&
4300		     !(OS_DATA_SIZE % (arg & MT_ST_BLKSIZE_MASK))  ) {
4301			 /*
4302			  * Only allowed to change the block size if you opened the
4303			  * device at the beginning of a file before writing anything.
4304			  * Note, that when reading, changing block_size is futile,
4305			  * as the size used when writing overrides it.
4306			  */
4307			 STp->block_size = (arg & MT_ST_BLKSIZE_MASK);
4308			 printk(KERN_INFO "%s:I: Block size set to %d bytes.\n",
4309					   name, STp->block_size);
4310			 return 0;
4311		 }
4312	 case MTSETDENSITY:       /* Set tape density */
4313	 case MTSETDRVBUFFER:     /* Set drive buffering */
4314	 case SET_DENS_AND_BLK:   /* Set density and block size */
4315		 chg_eof = 0;
4316		 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
4317			 return (-EIO);       /* Not allowed if data in buffer */
4318		 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
4319		     (arg & MT_ST_BLKSIZE_MASK) != 0                    &&
4320		     (arg & MT_ST_BLKSIZE_MASK) != STp->block_size       ) {
4321			 printk(KERN_WARNING "%s:W: Illegal to set block size to %d%s.\n",
4322						name, (int)(arg & MT_ST_BLKSIZE_MASK),
4323						(OS_DATA_SIZE % (arg & MT_ST_BLKSIZE_MASK))?"":" now");
4324			 return (-EINVAL);
4325		 }
4326		 return 0;  /* FIXME silently ignore if block size didn't change */
4327
4328	 default:
4329		return (-ENOSYS);
4330	}
4331
4332	SRpnt = osst_do_scsi(SRpnt, STp, cmd, datalen, direction, timeout, MAX_RETRIES, 1);
4333
4334	ioctl_result = (STp->buffer)->syscall_result;
4335
4336	if (!SRpnt) {
4337#if DEBUG
4338		printk(OSST_DEB_MSG "%s:D: Couldn't exec scsi cmd for IOCTL\n", name);
4339#endif
4340		return ioctl_result;
4341	}
4342
4343	if (!ioctl_result) {  /* SCSI command successful */
4344		STp->frame_seq_number = frame_seq_numbr;
4345		STp->logical_blk_num  = logical_blk_num;
4346	}
4347
4348os_bypass:
4349#if DEBUG
4350	if (debugging)
4351		printk(OSST_DEB_MSG "%s:D: IOCTL (%d) Result=%d\n", name, cmd_in, ioctl_result);
4352#endif
4353
4354	if (!ioctl_result) {				/* success */
4355
4356		if (cmd_in == MTFSFM) {
4357			 fileno--;
4358			 blkno--;
4359		}
4360		if (cmd_in == MTBSFM) {
4361			 fileno++;
4362			 blkno++;
4363		}
4364		STps->drv_block = blkno;
4365		STps->drv_file = fileno;
4366		STps->at_sm = at_sm;
4367
4368		if (cmd_in == MTEOM)
4369			STps->eof = ST_EOD;
4370		else if ((cmd_in == MTFSFM || cmd_in == MTBSF) && STps->eof == ST_FM_HIT) {
4371			ioctl_result = osst_seek_logical_blk(STp, &SRpnt, STp->logical_blk_num-1);
4372			STps->drv_block++;
4373			STp->logical_blk_num++;
4374			STp->frame_seq_number++;
4375			STp->frame_in_buffer = 0;
4376			STp->buffer->read_pointer = 0;
4377		}
4378		else if (cmd_in == MTFSF)
4379			STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_FM;
4380		else if (chg_eof)
4381			STps->eof = ST_NOEOF;
4382
4383		if (cmd_in == MTOFFL || cmd_in == MTUNLOAD)
4384			STp->rew_at_close = 0;
4385		else if (cmd_in == MTLOAD) {
4386			for (i=0; i < ST_NBR_PARTITIONS; i++) {
4387			    STp->ps[i].rw = ST_IDLE;
4388			    STp->ps[i].last_block_valid = 0;/* FIXME - where else is this field maintained? */
4389			}
4390			STp->partition = 0;
4391		}
4392
4393		if (cmd_in == MTREW) {
4394			ioctl_result = osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos); 
4395			if (ioctl_result > 0)
4396				ioctl_result = 0;
4397		}
4398
4399	} else if (cmd_in == MTBSF || cmd_in == MTBSFM ) {
4400		if (osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos) < 0)
4401			STps->drv_file = STps->drv_block = -1;
4402		else
4403			STps->drv_file = STps->drv_block = 0;
4404		STps->eof = ST_NOEOF;
4405	} else if (cmd_in == MTFSF || cmd_in == MTFSFM) {
4406		if (osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos) < 0)
4407			STps->drv_file = STps->drv_block = -1;
4408		else {
4409			STps->drv_file  = STp->filemark_cnt;
4410			STps->drv_block = 0;
4411		}
4412		STps->eof = ST_EOD;
4413	} else if (cmd_in == MTBSR || cmd_in == MTFSR || cmd_in == MTWEOF || cmd_in == MTEOM) {
4414		STps->drv_file = STps->drv_block = (-1);
4415		STps->eof = ST_NOEOF;
4416		STp->header_ok = 0;
4417	} else if (cmd_in == MTERASE) {
4418		STp->header_ok = 0;
4419	} else if (SRpnt) {  /* SCSI command was not completely successful. */
4420		if (SRpnt->sense[2] & 0x40) {
4421			STps->eof = ST_EOM_OK;
4422			STps->drv_block = 0;
4423		}
4424		if (chg_eof)
4425			STps->eof = ST_NOEOF;
4426
4427		if ((SRpnt->sense[2] & 0x0f) == BLANK_CHECK)
4428			STps->eof = ST_EOD;
4429
4430		if (cmd_in == MTLOAD && osst_wait_for_medium(STp, &SRpnt, 60))
4431			ioctl_result = osst_wait_ready(STp, &SRpnt, 5 * 60, OSST_WAIT_POSITION_COMPLETE);
4432	}
4433	*aSRpnt = SRpnt;
4434
4435	return ioctl_result;
4436}
4437
4438
4439/* Open the device */
4440static int __os_scsi_tape_open(struct inode * inode, struct file * filp)
4441{
4442	unsigned short	      flags;
4443	int		      i, b_size, new_session = 0, retval = 0;
4444	unsigned char	      cmd[MAX_COMMAND_SIZE];
4445	struct osst_request * SRpnt = NULL;
4446	struct osst_tape    * STp;
4447	struct st_modedef   * STm;
4448	struct st_partstat  * STps;
4449	char		    * name;
4450	int		      dev  = TAPE_NR(inode);
4451	int		      mode = TAPE_MODE(inode);
4452
4453	/*
4454	 * We really want to do nonseekable_open(inode, filp); here, but some
4455	 * versions of tar incorrectly call lseek on tapes and bail out if that
4456	 * fails.  So we disallow pread() and pwrite(), but permit lseeks.
4457	 */
4458	filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
4459
4460	write_lock(&os_scsi_tapes_lock);
4461	if (dev >= osst_max_dev || os_scsi_tapes == NULL ||
4462	    (STp = os_scsi_tapes[dev]) == NULL || !STp->device) {
4463		write_unlock(&os_scsi_tapes_lock);
4464		return (-ENXIO);
4465	}
4466
4467	name = tape_name(STp);
4468
4469	if (STp->in_use) {
4470		write_unlock(&os_scsi_tapes_lock);
4471#if DEBUG
4472		printk(OSST_DEB_MSG "%s:D: Device already in use.\n", name);
4473#endif
4474		return (-EBUSY);
4475	}
4476	if (scsi_device_get(STp->device)) {
4477		write_unlock(&os_scsi_tapes_lock);
4478#if DEBUG
4479                printk(OSST_DEB_MSG "%s:D: Failed scsi_device_get.\n", name);
4480#endif
4481		return (-ENXIO);
4482	}
4483	filp->private_data = STp;
4484	STp->in_use = 1;
4485	write_unlock(&os_scsi_tapes_lock);
4486	STp->rew_at_close = TAPE_REWIND(inode);
4487
4488	if( !scsi_block_when_processing_errors(STp->device) ) {
4489		return -ENXIO;
4490	}
4491
4492	if (mode != STp->current_mode) {
4493#if DEBUG
4494		if (debugging)
4495			printk(OSST_DEB_MSG "%s:D: Mode change from %d to %d.\n",
4496					       name, STp->current_mode, mode);
4497#endif
4498		new_session = 1;
4499		STp->current_mode = mode;
4500	}
4501	STm = &(STp->modes[STp->current_mode]);
4502
4503	flags = filp->f_flags;
4504	STp->write_prot = ((flags & O_ACCMODE) == O_RDONLY);
4505
4506	STp->raw = TAPE_IS_RAW(inode);
4507	if (STp->raw)
4508		STp->header_ok = 0;
4509
4510	/* Allocate data segments for this device's tape buffer */
4511	if (!enlarge_buffer(STp->buffer, STp->restr_dma)) {
4512		printk(KERN_ERR "%s:E: Unable to allocate memory segments for tape buffer.\n", name);
4513		retval = (-EOVERFLOW);
4514		goto err_out;
4515	}
4516	if (STp->buffer->buffer_size >= OS_FRAME_SIZE) {
4517		for (i = 0, b_size = 0; 
4518		     (i < STp->buffer->sg_segs) && ((b_size + STp->buffer->sg[i].length) <= OS_DATA_SIZE); 
4519		     b_size += STp->buffer->sg[i++].length);
4520		STp->buffer->aux = (os_aux_t *) (page_address(sg_page(&STp->buffer->sg[i])) + OS_DATA_SIZE - b_size);
4521#if DEBUG
4522		printk(OSST_DEB_MSG "%s:D: b_data points to %p in segment 0 at %p\n", name,
4523			STp->buffer->b_data, page_address(STp->buffer->sg[0].page));
4524		printk(OSST_DEB_MSG "%s:D: AUX points to %p in segment %d at %p\n", name,
4525			 STp->buffer->aux, i, page_address(STp->buffer->sg[i].page));
4526#endif
4527	} else {
4528		STp->buffer->aux = NULL; /* this had better never happen! */
4529		printk(KERN_NOTICE "%s:A: Framesize %d too large for buffer.\n", name, OS_FRAME_SIZE);
4530		retval = (-EIO);
4531		goto err_out;
4532	}
4533	STp->buffer->writing = 0;
4534	STp->buffer->syscall_result = 0;
4535	STp->dirty = 0;
4536	for (i=0; i < ST_NBR_PARTITIONS; i++) {
4537		STps = &(STp->ps[i]);
4538		STps->rw = ST_IDLE;
4539	}
4540	STp->ready = ST_READY;
4541#if DEBUG
4542	STp->nbr_waits = STp->nbr_finished = 0;
4543#endif
4544
4545	memset (cmd, 0, MAX_COMMAND_SIZE);
4546	cmd[0] = TEST_UNIT_READY;
4547
4548	SRpnt = osst_do_scsi(NULL, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
4549	if (!SRpnt) {
4550		retval = (STp->buffer)->syscall_result;		/* FIXME - valid? */
4551		goto err_out;
4552	}
4553	if ((SRpnt->sense[0] & 0x70) == 0x70      &&
4554	    (SRpnt->sense[2] & 0x0f) == NOT_READY &&
4555	     SRpnt->sense[12]        == 4         ) {
4556#if DEBUG
4557		printk(OSST_DEB_MSG "%s:D: Unit not ready, cause %x\n", name, SRpnt->sense[13]);
4558#endif
4559		if (filp->f_flags & O_NONBLOCK) {
4560			retval = -EAGAIN;
4561			goto err_out;
4562		}
4563		if (SRpnt->sense[13] == 2) {	/* initialize command required (LOAD) */
4564			memset (cmd, 0, MAX_COMMAND_SIZE);
4565        		cmd[0] = START_STOP;
4566			cmd[1] = 1;
4567			cmd[4] = 1;
4568			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4569					     STp->timeout, MAX_RETRIES, 1);
4570		}
4571		osst_wait_ready(STp, &SRpnt, (SRpnt->sense[13]==1?15:3) * 60, 0);
4572	}
4573	if ((SRpnt->sense[0] & 0x70) == 0x70 &&
4574	    (SRpnt->sense[2] & 0x0f) == UNIT_ATTENTION) { /* New media? */
4575#if DEBUG
4576		printk(OSST_DEB_MSG "%s:D: Unit wants attention\n", name);
4577#endif
4578		STp->header_ok = 0;
4579
4580		for (i=0; i < 10; i++) {
4581
4582			memset (cmd, 0, MAX_COMMAND_SIZE);
4583			cmd[0] = TEST_UNIT_READY;
4584
4585			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4586					     STp->timeout, MAX_RETRIES, 1);
4587			if ((SRpnt->sense[0] & 0x70) != 0x70 ||
4588			    (SRpnt->sense[2] & 0x0f) != UNIT_ATTENTION)
4589				break;
4590		}
4591
4592		STp->pos_unknown = 0;
4593		STp->partition = STp->new_partition = 0;
4594		if (STp->can_partitions)
4595			STp->nbr_partitions = 1;  /* This guess will be updated later if necessary */
4596		for (i=0; i < ST_NBR_PARTITIONS; i++) {
4597			STps = &(STp->ps[i]);
4598			STps->rw = ST_IDLE;		/* FIXME - seems to be redundant... */
4599			STps->eof = ST_NOEOF;
4600			STps->at_sm = 0;
4601			STps->last_block_valid = 0;
4602			STps->drv_block = 0;
4603			STps->drv_file = 0 ;
4604		}
4605		new_session = 1;
4606		STp->recover_count = 0;
4607		STp->abort_count = 0;
4608	}
4609	/*
4610	 * if we have valid headers from before, and the drive/tape seem untouched,
4611	 * open without reconfiguring and re-reading the headers
4612	 */
4613	if (!STp->buffer->syscall_result && STp->header_ok &&
4614	    !SRpnt->result && SRpnt->sense[0] == 0) {
4615
4616		memset(cmd, 0, MAX_COMMAND_SIZE);
4617		cmd[0] = MODE_SENSE;
4618		cmd[1] = 8;
4619		cmd[2] = VENDOR_IDENT_PAGE;
4620		cmd[4] = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH;
4621
4622		SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
4623
4624		if (STp->buffer->syscall_result                     ||
4625		    STp->buffer->b_data[MODE_HEADER_LENGTH + 2] != 'L' ||
4626		    STp->buffer->b_data[MODE_HEADER_LENGTH + 3] != 'I' ||
4627		    STp->buffer->b_data[MODE_HEADER_LENGTH + 4] != 'N' ||
4628		    STp->buffer->b_data[MODE_HEADER_LENGTH + 5] != '4'  ) {
4629#if DEBUG
4630			printk(OSST_DEB_MSG "%s:D: Signature was changed to %c%c%c%c\n", name,
4631			  STp->buffer->b_data[MODE_HEADER_LENGTH + 2],
4632			  STp->buffer->b_data[MODE_HEADER_LENGTH + 3],
4633			  STp->buffer->b_data[MODE_HEADER_LENGTH + 4],
4634			  STp->buffer->b_data[MODE_HEADER_LENGTH + 5]);
4635#endif
4636			STp->header_ok = 0;
4637		}
4638		i = STp->first_frame_position;
4639		if (STp->header_ok && i == osst_get_frame_position(STp, &SRpnt)) {
4640			if (STp->door_locked == ST_UNLOCKED) {
4641				if (do_door_lock(STp, 1))
4642					printk(KERN_INFO "%s:I: Can't lock drive door\n", name);
4643				else
4644					STp->door_locked = ST_LOCKED_AUTO;
4645			}
4646			if (!STp->frame_in_buffer) {
4647				STp->block_size = (STm->default_blksize > 0) ?
4648							STm->default_blksize : OS_DATA_SIZE;
4649				STp->buffer->buffer_bytes = STp->buffer->read_pointer = 0;
4650			}
4651			STp->buffer->buffer_blocks = OS_DATA_SIZE / STp->block_size;
4652			STp->fast_open = 1;
4653			osst_release_request(SRpnt);
4654			return 0;
4655		}
4656#if DEBUG
4657		if (i != STp->first_frame_position)
4658			printk(OSST_DEB_MSG "%s:D: Tape position changed from %d to %d\n",
4659						name, i, STp->first_frame_position);
4660#endif
4661		STp->header_ok = 0;
4662	}
4663	STp->fast_open = 0;
4664
4665	if ((STp->buffer)->syscall_result != 0 &&   /* in all error conditions except no medium */ 
4666	    (SRpnt->sense[2] != 2 || SRpnt->sense[12] != 0x3A) ) {
4667
4668		memset(cmd, 0, MAX_COMMAND_SIZE);
4669		cmd[0] = MODE_SELECT;
4670		cmd[1] = 0x10;
4671		cmd[4] = 4 + MODE_HEADER_LENGTH;
4672
4673		(STp->buffer)->b_data[0] = cmd[4] - 1;
4674		(STp->buffer)->b_data[1] = 0;			/* Medium Type - ignoring */
4675		(STp->buffer)->b_data[2] = 0;			/* Reserved */
4676		(STp->buffer)->b_data[3] = 0;			/* Block Descriptor Length */
4677		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = 0x3f;
4678		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 1;
4679		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 2;
4680		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = 3;
4681
4682#if DEBUG
4683		printk(OSST_DEB_MSG "%s:D: Applying soft reset\n", name);
4684#endif
4685		SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
4686
4687		STp->header_ok = 0;
4688
4689		for (i=0; i < 10; i++) {
4690
4691			memset (cmd, 0, MAX_COMMAND_SIZE);
4692			cmd[0] = TEST_UNIT_READY;
4693
4694			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4695						    STp->timeout, MAX_RETRIES, 1);
4696			if ((SRpnt->sense[0] & 0x70) != 0x70 ||
4697			    (SRpnt->sense[2] & 0x0f) == NOT_READY)
4698			break;
4699
4700			if ((SRpnt->sense[2] & 0x0f) == UNIT_ATTENTION) {
4701				int j;
4702
4703				STp->pos_unknown = 0;
4704				STp->partition = STp->new_partition = 0;
4705				if (STp->can_partitions)
4706					STp->nbr_partitions = 1;  /* This guess will be updated later if necessary */
4707				for (j = 0; j < ST_NBR_PARTITIONS; j++) {
4708					STps = &(STp->ps[j]);
4709					STps->rw = ST_IDLE;
4710					STps->eof = ST_NOEOF;
4711					STps->at_sm = 0;
4712					STps->last_block_valid = 0;
4713					STps->drv_block = 0;
4714					STps->drv_file = 0 ;
4715				}
4716				new_session = 1;
4717			}
4718		}
4719	}
4720
4721	if (osst_wait_ready(STp, &SRpnt, 15 * 60, 0))		/* FIXME - not allowed with NOBLOCK */
4722		 printk(KERN_INFO "%s:I: Device did not become Ready in open\n", name);
4723
4724	if ((STp->buffer)->syscall_result != 0) {
4725		if ((STp->device)->scsi_level >= SCSI_2 &&
4726		    (SRpnt->sense[0] & 0x70) == 0x70 &&
4727		    (SRpnt->sense[2] & 0x0f) == NOT_READY &&
4728		     SRpnt->sense[12] == 0x3a) { /* Check ASC */
4729			STp->ready = ST_NO_TAPE;
4730		} else
4731			STp->ready = ST_NOT_READY;
4732		osst_release_request(SRpnt);
4733		SRpnt = NULL;
4734		STp->density = 0;   	/* Clear the erroneous "residue" */
4735		STp->write_prot = 0;
4736		STp->block_size = 0;
4737		STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
4738		STp->partition = STp->new_partition = 0;
4739		STp->door_locked = ST_UNLOCKED;
4740		return 0;
4741	}
4742
4743	osst_configure_onstream(STp, &SRpnt);
4744
4745	STp->block_size = STp->raw ? OS_FRAME_SIZE : (
4746			     (STm->default_blksize > 0) ? STm->default_blksize : OS_DATA_SIZE);
4747	STp->buffer->buffer_blocks = STp->raw ? 1 : OS_DATA_SIZE / STp->block_size;
4748	STp->buffer->buffer_bytes  =
4749	STp->buffer->read_pointer  =
4750	STp->frame_in_buffer       = 0;
4751
4752#if DEBUG
4753	if (debugging)
4754		printk(OSST_DEB_MSG "%s:D: Block size: %d, frame size: %d, buffer size: %d (%d blocks).\n",
4755		     name, STp->block_size, OS_FRAME_SIZE, (STp->buffer)->buffer_size,
4756		     (STp->buffer)->buffer_blocks);
4757#endif
4758
4759	if (STp->drv_write_prot) {
4760		STp->write_prot = 1;
4761#if DEBUG
4762		if (debugging)
4763			printk(OSST_DEB_MSG "%s:D: Write protected\n", name);
4764#endif
4765		if ((flags & O_ACCMODE) == O_WRONLY || (flags & O_ACCMODE) == O_RDWR) {
4766			retval = (-EROFS);
4767			goto err_out;
4768		}
4769	}
4770
4771	if (new_session) {  /* Change the drive parameters for the new mode */
4772#if DEBUG
4773		if (debugging)
4774	printk(OSST_DEB_MSG "%s:D: New Session\n", name);
4775#endif
4776		STp->density_changed = STp->blksize_changed = 0;
4777		STp->compression_changed = 0;
4778	}
4779
4780	/*
4781	 * properly position the tape and check the ADR headers
4782	 */
4783	if (STp->door_locked == ST_UNLOCKED) {
4784		 if (do_door_lock(STp, 1))
4785			printk(KERN_INFO "%s:I: Can't lock drive door\n", name);
4786		 else
4787			STp->door_locked = ST_LOCKED_AUTO;
4788	}
4789
4790	osst_analyze_headers(STp, &SRpnt);
4791
4792	osst_release_request(SRpnt);
4793	SRpnt = NULL;
4794
4795	return 0;
4796
4797err_out:
4798	if (SRpnt != NULL)
4799		osst_release_request(SRpnt);
4800	normalize_buffer(STp->buffer);
4801	STp->header_ok = 0;
4802	STp->in_use = 0;
4803	scsi_device_put(STp->device);
4804
4805	return retval;
4806}
4807
4808/* BKL pushdown: spaghetti avoidance wrapper */
4809static int os_scsi_tape_open(struct inode * inode, struct file * filp)
4810{
4811	int ret;
4812
4813	mutex_lock(&osst_int_mutex);
4814	ret = __os_scsi_tape_open(inode, filp);
4815	mutex_unlock(&osst_int_mutex);
4816	return ret;
4817}
4818
4819
4820
4821/* Flush the tape buffer before close */
4822static int os_scsi_tape_flush(struct file * filp, fl_owner_t id)
4823{
4824	int		      result = 0, result2;
4825	struct osst_tape    * STp    = filp->private_data;
4826	struct st_modedef   * STm    = &(STp->modes[STp->current_mode]);
4827	struct st_partstat  * STps   = &(STp->ps[STp->partition]);
4828	struct osst_request * SRpnt  = NULL;
4829	char		    * name   = tape_name(STp);
4830
4831	if (file_count(filp) > 1)
4832		return 0;
4833
4834	if ((STps->rw == ST_WRITING || STp->dirty) && !STp->pos_unknown) {
4835		STp->write_type = OS_WRITE_DATA;
4836		result = osst_flush_write_buffer(STp, &SRpnt);
4837		if (result != 0 && result != (-ENOSPC))
4838			goto out;
4839	}
4840	if ( STps->rw >= ST_WRITING && !STp->pos_unknown) {
4841
4842#if DEBUG
4843		if (debugging) {
4844			printk(OSST_DEB_MSG "%s:D: File length %ld bytes.\n",
4845					       name, (long)(filp->f_pos));
4846			printk(OSST_DEB_MSG "%s:D: Async write waits %d, finished %d.\n",
4847					       name, STp->nbr_waits, STp->nbr_finished);
4848		}
4849#endif
4850		result = osst_write_trailer(STp, &SRpnt, !(STp->rew_at_close));
4851#if DEBUG
4852		if (debugging)
4853			printk(OSST_DEB_MSG "%s:D: Buffer flushed, %d EOF(s) written\n",
4854					       name, 1+STp->two_fm);
4855#endif
4856	}
4857	else if (!STp->rew_at_close) {
4858		STps = &(STp->ps[STp->partition]);
4859		if (!STm->sysv || STps->rw != ST_READING) {
4860			if (STp->can_bsr)
4861				result = osst_flush_buffer(STp, &SRpnt, 0); /* this is the default path */
4862			else if (STps->eof == ST_FM_HIT) {
4863				result = cross_eof(STp, &SRpnt, 0);
4864					if (result) {
4865						if (STps->drv_file >= 0)
4866							STps->drv_file++;
4867						STps->drv_block = 0;
4868						STps->eof = ST_FM;
4869					}
4870					else
4871						STps->eof = ST_NOEOF;
4872			}
4873		}
4874		else if ((STps->eof == ST_NOEOF &&
4875			  !(result = cross_eof(STp, &SRpnt, 1))) ||
4876			 STps->eof == ST_FM_HIT) {
4877			if (STps->drv_file >= 0)
4878				STps->drv_file++;
4879			STps->drv_block = 0;
4880			STps->eof = ST_FM;
4881		}
4882	}
4883
4884out:
4885	if (STp->rew_at_close) {
4886		result2 = osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos);
4887		STps->drv_file = STps->drv_block = STp->frame_seq_number = STp->logical_blk_num = 0;
4888		if (result == 0 && result2 < 0)
4889			result = result2;
4890	}
4891	if (SRpnt) osst_release_request(SRpnt);
4892
4893	if (STp->abort_count || STp->recover_count) {
4894		printk(KERN_INFO "%s:I:", name);
4895		if (STp->abort_count)
4896			printk(" %d unrecovered errors", STp->abort_count);
4897		if (STp->recover_count)
4898			printk(" %d recovered errors", STp->recover_count);
4899		if (STp->write_count)
4900			printk(" in %d frames written", STp->write_count);
4901		if (STp->read_count)
4902			printk(" in %d frames read", STp->read_count);
4903		printk("\n");
4904		STp->recover_count = 0;
4905		STp->abort_count   = 0;
4906	}
4907	STp->write_count = 0;
4908	STp->read_count  = 0;
4909
4910	return result;
4911}
4912
4913
4914/* Close the device and release it */
4915static int os_scsi_tape_close(struct inode * inode, struct file * filp)
4916{
4917	int		      result = 0;
4918	struct osst_tape    * STp    = filp->private_data;
4919
4920	if (STp->door_locked == ST_LOCKED_AUTO)
4921		do_door_lock(STp, 0);
4922
4923	if (STp->raw)
4924		STp->header_ok = 0;
4925	
4926	normalize_buffer(STp->buffer);
4927	write_lock(&os_scsi_tapes_lock);
4928	STp->in_use = 0;
4929	write_unlock(&os_scsi_tapes_lock);
4930
4931	scsi_device_put(STp->device);
4932
4933	return result;
4934}
4935
4936
4937/* The ioctl command */
4938static long osst_ioctl(struct file * file,
4939	 unsigned int cmd_in, unsigned long arg)
4940{
4941	int		      i, cmd_nr, cmd_type, blk, retval = 0;
4942	struct st_modedef   * STm;
4943	struct st_partstat  * STps;
4944	struct osst_request * SRpnt = NULL;
4945	struct osst_tape    * STp   = file->private_data;
4946	char		    * name  = tape_name(STp);
4947	void	    __user  * p     = (void __user *)arg;
4948
4949	mutex_lock(&osst_int_mutex);
4950	if (mutex_lock_interruptible(&STp->lock)) {
4951		mutex_unlock(&osst_int_mutex);
4952		return -ERESTARTSYS;
4953	}
4954
4955#if DEBUG
4956	if (debugging && !STp->in_use) {
4957		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
4958		retval = (-EIO);
4959		goto out;
4960	}
4961#endif
4962	STm = &(STp->modes[STp->current_mode]);
4963	STps = &(STp->ps[STp->partition]);
4964
4965	/*
4966	 * If we are in the middle of error recovery, don't let anyone
4967	 * else try and use this device.  Also, if error recovery fails, it
4968	 * may try and take the device offline, in which case all further
4969	 * access to the device is prohibited.
4970	 */
4971	if( !scsi_block_when_processing_errors(STp->device) ) {
4972		retval = (-ENXIO);
 
4973		goto out;
4974	}
4975
4976	cmd_type = _IOC_TYPE(cmd_in);
4977	cmd_nr   = _IOC_NR(cmd_in);
4978#if DEBUG
4979	printk(OSST_DEB_MSG "%s:D: Ioctl %d,%d in %s mode\n", name,
4980			    cmd_type, cmd_nr, STp->raw?"raw":"normal");
4981#endif
4982	if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
4983		struct mtop mtc;
4984		int    auto_weof = 0;
4985
4986		if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
4987			retval = (-EINVAL);
4988			goto out;
4989		}
4990
4991		i = copy_from_user((char *) &mtc, p, sizeof(struct mtop));
4992		if (i) {
4993			retval = (-EFAULT);
4994			goto out;
4995		}
4996
4997		if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
4998			printk(KERN_WARNING "%s:W: MTSETDRVBUFFER only allowed for root.\n", name);
4999			retval = (-EPERM);
5000			goto out;
5001		}
5002
5003		if (!STm->defined && (mtc.mt_op != MTSETDRVBUFFER && (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
5004			retval = (-ENXIO);
5005			goto out;
5006		}
5007
5008		if (!STp->pos_unknown) {
5009
5010			if (STps->eof == ST_FM_HIT) {
5011				if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM|| mtc.mt_op == MTEOM) {
5012					mtc.mt_count -= 1;
5013					if (STps->drv_file >= 0)
5014						STps->drv_file += 1;
5015				}
5016				else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
5017					mtc.mt_count += 1;
5018					if (STps->drv_file >= 0)
5019						STps->drv_file += 1;
5020				}
5021			}
5022
5023			if (mtc.mt_op == MTSEEK) {
5024				/* Old position must be restored if partition will be changed */
5025				i = !STp->can_partitions || (STp->new_partition != STp->partition);
5026			}
5027			else {
5028				i = mtc.mt_op == MTREW   || mtc.mt_op == MTOFFL ||
5029				    mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM  ||
5030				    mtc.mt_op == MTLOCK  || mtc.mt_op == MTLOAD ||
5031				    mtc.mt_op == MTFSF   || mtc.mt_op == MTFSFM ||
5032				    mtc.mt_op == MTBSF   || mtc.mt_op == MTBSFM ||
5033				    mtc.mt_op == MTCOMPRESSION;
5034			}
5035			i = osst_flush_buffer(STp, &SRpnt, i);
5036			if (i < 0) {
5037				retval = i;
5038				goto out;
5039			}
5040		}
5041		else {
5042			/*
5043			 * If there was a bus reset, block further access
5044			 * to this device.  If the user wants to rewind the tape,
5045			 * then reset the flag and allow access again.
5046			 */
5047			if(mtc.mt_op != MTREW   &&
5048			   mtc.mt_op != MTOFFL  &&
5049			   mtc.mt_op != MTRETEN &&
5050			   mtc.mt_op != MTERASE &&
5051			   mtc.mt_op != MTSEEK  &&
5052			   mtc.mt_op != MTEOM)   {
5053				retval = (-EIO);
5054				goto out;
5055			}
5056			reset_state(STp);
5057			/* remove this when the midlevel properly clears was_reset */
5058			STp->device->was_reset = 0;
5059		}
5060
5061		if (mtc.mt_op != MTCOMPRESSION  && mtc.mt_op != MTLOCK         &&
5062		    mtc.mt_op != MTNOP          && mtc.mt_op != MTSETBLK       &&
5063		    mtc.mt_op != MTSETDENSITY   && mtc.mt_op != MTSETDRVBUFFER && 
5064		    mtc.mt_op != MTMKPART       && mtc.mt_op != MTSETPART      &&
5065		    mtc.mt_op != MTWEOF         && mtc.mt_op != MTWSM           ) {
5066
5067			/*
5068			 * The user tells us to move to another position on the tape.
5069			 * If we were appending to the tape content, that would leave
5070			 * the tape without proper end, in that case write EOD and
5071			 * update the header to reflect its position.
5072			 */
5073#if DEBUG
5074			printk(KERN_WARNING "%s:D: auto_weod %s at ffp=%d,efp=%d,fsn=%d,lbn=%d,fn=%d,bn=%d\n", name,
5075					STps->rw >= ST_WRITING ? "write" : STps->rw == ST_READING ? "read" : "idle",
5076					STp->first_frame_position, STp->eod_frame_ppos, STp->frame_seq_number,
5077					STp->logical_blk_num, STps->drv_file, STps->drv_block );
5078#endif
5079			if (STps->rw >= ST_WRITING && STp->first_frame_position >= STp->eod_frame_ppos) {
5080				auto_weof = ((STp->write_type != OS_WRITE_NEW_MARK) &&
5081							!(mtc.mt_op == MTREW || mtc.mt_op == MTOFFL));
5082				i = osst_write_trailer(STp, &SRpnt,
5083							!(mtc.mt_op == MTREW || mtc.mt_op == MTOFFL));
5084#if DEBUG
5085				printk(KERN_WARNING "%s:D: post trailer xeof=%d,ffp=%d,efp=%d,fsn=%d,lbn=%d,fn=%d,bn=%d\n",
5086						name, auto_weof, STp->first_frame_position, STp->eod_frame_ppos,
5087						STp->frame_seq_number, STp->logical_blk_num, STps->drv_file, STps->drv_block );
5088#endif
5089				if (i < 0) {
5090					retval = i;
5091					goto out;
5092				}
5093			}
5094			STps->rw = ST_IDLE;
5095		}
5096
5097		if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
5098			do_door_lock(STp, 0);  /* Ignore result! */
5099
5100		if (mtc.mt_op == MTSETDRVBUFFER &&
5101		   (mtc.mt_count & MT_ST_OPTIONS) != 0) {
5102			retval = osst_set_options(STp, mtc.mt_count);
5103			goto out;
5104		}
5105
5106		if (mtc.mt_op == MTSETPART) {
5107			if (mtc.mt_count >= STp->nbr_partitions)
5108				retval = -EINVAL;
5109			else {
5110				STp->new_partition = mtc.mt_count;
5111				retval = 0;
5112			}
5113			goto out;
5114		}
5115
5116		if (mtc.mt_op == MTMKPART) {
5117			if (!STp->can_partitions) {
5118				retval = (-EINVAL);
5119				goto out;
5120			}
5121			if ((i = osst_int_ioctl(STp, &SRpnt, MTREW, 0)) < 0 /*||
5122			    (i = partition_tape(inode, mtc.mt_count)) < 0*/) {
5123				retval = i;
5124				goto out;
5125			}
5126			for (i=0; i < ST_NBR_PARTITIONS; i++) {
5127				STp->ps[i].rw = ST_IDLE;
5128				STp->ps[i].at_sm = 0;
5129				STp->ps[i].last_block_valid = 0;
5130			}
5131			STp->partition = STp->new_partition = 0;
5132			STp->nbr_partitions = 1;  /* Bad guess ?-) */
5133			STps->drv_block = STps->drv_file = 0;
5134			retval = 0;
5135			goto out;
5136	 	}
5137
5138		if (mtc.mt_op == MTSEEK) {
5139			if (STp->raw)
5140				i = osst_set_frame_position(STp, &SRpnt, mtc.mt_count, 0);
5141			else
5142				i = osst_seek_sector(STp, &SRpnt, mtc.mt_count);
5143			if (!STp->can_partitions)
5144				STp->ps[0].rw = ST_IDLE;
5145			retval = i;
5146			goto out;
5147		}
5148 
5149		if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
5150			retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
5151			goto out;
5152		}
5153
5154		if (auto_weof)
5155			cross_eof(STp, &SRpnt, 0);
5156
5157		if (mtc.mt_op == MTCOMPRESSION)
5158			retval = -EINVAL;       /* OnStream drives don't have compression hardware */
5159		else
5160			/* MTBSF MTBSFM MTBSR MTBSS MTEOM MTERASE MTFSF MTFSFB MTFSR MTFSS
5161			 * MTLOAD MTOFFL MTRESET MTRETEN MTREW MTUNLOAD MTWEOF MTWSM */
5162			retval = osst_int_ioctl(STp, &SRpnt, mtc.mt_op, mtc.mt_count);
5163		goto out;
5164	}
5165
5166	if (!STm->defined) {
5167		retval = (-ENXIO);
5168		goto out;
5169	}
5170
5171	if ((i = osst_flush_buffer(STp, &SRpnt, 0)) < 0) {
5172		retval = i;
5173		goto out;
5174	}
5175
5176	if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
5177		struct mtget mt_status;
5178
5179		if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
5180			 retval = (-EINVAL);
5181			 goto out;
5182		}
5183
5184		mt_status.mt_type = MT_ISONSTREAM_SC;
5185		mt_status.mt_erreg = STp->recover_erreg << MT_ST_SOFTERR_SHIFT;
5186		mt_status.mt_dsreg =
5187			((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
5188			((STp->density    << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
5189		mt_status.mt_blkno = STps->drv_block;
5190		mt_status.mt_fileno = STps->drv_file;
5191		if (STp->block_size != 0) {
5192			if (STps->rw == ST_WRITING)
5193				mt_status.mt_blkno += (STp->buffer)->buffer_bytes / STp->block_size;
5194			else if (STps->rw == ST_READING)
5195				mt_status.mt_blkno -= ((STp->buffer)->buffer_bytes +
5196							STp->block_size - 1) / STp->block_size;
5197		}
5198
5199		mt_status.mt_gstat = 0;
5200		if (STp->drv_write_prot)
5201			mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
5202		if (mt_status.mt_blkno == 0) {
5203			if (mt_status.mt_fileno == 0)
5204				mt_status.mt_gstat |= GMT_BOT(0xffffffff);
5205			else
5206				mt_status.mt_gstat |= GMT_EOF(0xffffffff);
5207		}
5208		mt_status.mt_resid = STp->partition;
5209		if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
5210			mt_status.mt_gstat |= GMT_EOT(0xffffffff);
5211		else if (STps->eof >= ST_EOM_OK)
5212			mt_status.mt_gstat |= GMT_EOD(0xffffffff);
5213		if (STp->density == 1)
5214			mt_status.mt_gstat |= GMT_D_800(0xffffffff);
5215		else if (STp->density == 2)
5216			mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
5217		else if (STp->density == 3)
5218			mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
5219		if (STp->ready == ST_READY)
5220			mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
5221		if (STp->ready == ST_NO_TAPE)
5222			mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
5223		if (STps->at_sm)
5224			mt_status.mt_gstat |= GMT_SM(0xffffffff);
5225		if (STm->do_async_writes || (STm->do_buffer_writes && STp->block_size != 0) ||
5226		    STp->drv_buffer != 0)
5227			mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
5228
5229		i = copy_to_user(p, &mt_status, sizeof(struct mtget));
5230		if (i) {
5231			retval = (-EFAULT);
5232			goto out;
5233		}
5234
5235		STp->recover_erreg = 0;  /* Clear after read */
5236		retval = 0;
5237		goto out;
5238	} /* End of MTIOCGET */
5239
5240	if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
5241		struct mtpos mt_pos;
5242
5243		if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
5244			retval = (-EINVAL);
5245			goto out;
5246		}
5247		if (STp->raw)
5248			blk = osst_get_frame_position(STp, &SRpnt);
5249		else
5250			blk = osst_get_sector(STp, &SRpnt);
5251		if (blk < 0) {
5252			retval = blk;
5253			goto out;
5254		}
5255		mt_pos.mt_blkno = blk;
5256		i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
5257		if (i)
5258			retval = -EFAULT;
5259		goto out;
5260	}
5261	if (SRpnt) osst_release_request(SRpnt);
5262
5263	mutex_unlock(&STp->lock);
5264
5265	retval = scsi_ioctl(STp->device, cmd_in, p);
5266	mutex_unlock(&osst_int_mutex);
5267	return retval;
5268
5269out:
5270	if (SRpnt) osst_release_request(SRpnt);
5271
5272	mutex_unlock(&STp->lock);
5273	mutex_unlock(&osst_int_mutex);
5274
5275	return retval;
5276}
5277
5278#ifdef CONFIG_COMPAT
5279static long osst_compat_ioctl(struct file * file, unsigned int cmd_in, unsigned long arg)
5280{
5281	struct osst_tape *STp = file->private_data;
5282	struct scsi_device *sdev = STp->device;
5283	int ret = -ENOIOCTLCMD;
5284	if (sdev->host->hostt->compat_ioctl) {
5285
5286		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
5287
5288	}
5289	return ret;
5290}
5291#endif
5292
5293
5294
5295/* Memory handling routines */
5296
5297/* Try to allocate a new tape buffer skeleton. Caller must not hold os_scsi_tapes_lock */
5298static struct osst_buffer * new_tape_buffer( int from_initialization, int need_dma, int max_sg )
5299{
5300	int i;
5301	gfp_t priority;
5302	struct osst_buffer *tb;
5303
5304	if (from_initialization)
5305		priority = GFP_ATOMIC;
5306	else
5307		priority = GFP_KERNEL;
5308
5309	i = sizeof(struct osst_buffer) + (osst_max_sg_segs - 1) * sizeof(struct scatterlist);
5310	tb = kzalloc(i, priority);
5311	if (!tb) {
5312		printk(KERN_NOTICE "osst :I: Can't allocate new tape buffer.\n");
5313		return NULL;
5314	}
5315
5316	tb->sg_segs = tb->orig_sg_segs = 0;
5317	tb->use_sg = max_sg;
5318	tb->in_use = 1;
5319	tb->dma = need_dma;
5320	tb->buffer_size = 0;
5321#if DEBUG
5322	if (debugging) 
5323		printk(OSST_DEB_MSG
5324			"osst :D: Allocated tape buffer skeleton (%d bytes, %d segments, dma: %d).\n",
5325			   i, max_sg, need_dma);
5326#endif
5327	return tb;
5328}
5329
5330/* Try to allocate a temporary (while a user has the device open) enlarged tape buffer */
5331static int enlarge_buffer(struct osst_buffer *STbuffer, int need_dma)
5332{
5333	int segs, nbr, max_segs, b_size, order, got;
5334	gfp_t priority;
5335
5336	if (STbuffer->buffer_size >= OS_FRAME_SIZE)
5337		return 1;
5338
5339	if (STbuffer->sg_segs) {
5340		printk(KERN_WARNING "osst :A: Buffer not previously normalized.\n");
5341		normalize_buffer(STbuffer);
5342	}
5343	/* See how many segments we can use -- need at least two */
5344	nbr = max_segs = STbuffer->use_sg;
5345	if (nbr <= 2)
5346		return 0;
5347
5348	priority = GFP_KERNEL /* | __GFP_NOWARN */;
5349	if (need_dma)
5350		priority |= GFP_DMA;
5351
5352	/* Try to allocate the first segment up to OS_DATA_SIZE and the others
5353	   big enough to reach the goal (code assumes no segments in place) */
5354	for (b_size = OS_DATA_SIZE, order = OSST_FIRST_ORDER; b_size >= PAGE_SIZE; order--, b_size /= 2) {
5355		struct page *page = alloc_pages(priority, order);
5356
5357		STbuffer->sg[0].offset = 0;
5358		if (page != NULL) {
5359		    sg_set_page(&STbuffer->sg[0], page, b_size, 0);
5360		    STbuffer->b_data = page_address(page);
5361		    break;
5362		}
5363	}
5364	if (sg_page(&STbuffer->sg[0]) == NULL) {
5365		printk(KERN_NOTICE "osst :I: Can't allocate tape buffer main segment.\n");
5366		return 0;
5367	}
5368	/* Got initial segment of 'bsize,order', continue with same size if possible, except for AUX */
5369	for (segs=STbuffer->sg_segs=1, got=b_size;
5370	     segs < max_segs && got < OS_FRAME_SIZE; ) {
5371		struct page *page = alloc_pages(priority, (OS_FRAME_SIZE - got <= PAGE_SIZE) ? 0 : order);
5372		STbuffer->sg[segs].offset = 0;
5373		if (page == NULL) {
5374			printk(KERN_WARNING "osst :W: Failed to enlarge buffer to %d bytes.\n",
5375						OS_FRAME_SIZE);
5376#if DEBUG
5377			STbuffer->buffer_size = got;
5378#endif
5379			normalize_buffer(STbuffer);
5380			return 0;
5381		}
5382		sg_set_page(&STbuffer->sg[segs], page, (OS_FRAME_SIZE - got <= PAGE_SIZE / 2) ? (OS_FRAME_SIZE - got) : b_size, 0);
5383		got += STbuffer->sg[segs].length;
5384		STbuffer->buffer_size = got;
5385		STbuffer->sg_segs = ++segs;
5386	}
5387#if DEBUG
5388	if (debugging) {
5389		printk(OSST_DEB_MSG
5390			   "osst :D: Expanded tape buffer (%d bytes, %d->%d segments, dma: %d, at: %p).\n",
5391			   got, STbuffer->orig_sg_segs, STbuffer->sg_segs, need_dma, STbuffer->b_data);
5392		printk(OSST_DEB_MSG
5393			   "osst :D: segment sizes: first %d at %p, last %d bytes at %p.\n",
5394			   STbuffer->sg[0].length, page_address(STbuffer->sg[0].page),
5395			   STbuffer->sg[segs-1].length, page_address(STbuffer->sg[segs-1].page));
5396	}
5397#endif
5398
5399	return 1;
5400}
5401
5402
5403/* Release the segments */
5404static void normalize_buffer(struct osst_buffer *STbuffer)
5405{
5406  int i, order, b_size;
5407
5408	for (i=0; i < STbuffer->sg_segs; i++) {
5409
5410		for (b_size = PAGE_SIZE, order = 0;
5411		     b_size < STbuffer->sg[i].length;
5412		     b_size *= 2, order++);
5413
5414		__free_pages(sg_page(&STbuffer->sg[i]), order);
5415		STbuffer->buffer_size -= STbuffer->sg[i].length;
5416	}
5417#if DEBUG
5418	if (debugging && STbuffer->orig_sg_segs < STbuffer->sg_segs)
5419		printk(OSST_DEB_MSG "osst :D: Buffer at %p normalized to %d bytes (segs %d).\n",
5420			     STbuffer->b_data, STbuffer->buffer_size, STbuffer->sg_segs);
5421#endif
5422	STbuffer->sg_segs = STbuffer->orig_sg_segs = 0;
5423}
5424
5425
5426/* Move data from the user buffer to the tape buffer. Returns zero (success) or
5427   negative error code. */
5428static int append_to_buffer(const char __user *ubp, struct osst_buffer *st_bp, int do_count)
5429{
5430	int i, cnt, res, offset;
5431
5432	for (i=0, offset=st_bp->buffer_bytes;
5433	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5434	offset -= st_bp->sg[i].length;
5435	if (i == st_bp->sg_segs) {  /* Should never happen */
5436		printk(KERN_WARNING "osst :A: Append_to_buffer offset overflow.\n");
5437		return (-EIO);
5438	}
5439	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {
5440		cnt = st_bp->sg[i].length - offset < do_count ?
5441		      st_bp->sg[i].length - offset : do_count;
5442		res = copy_from_user(page_address(sg_page(&st_bp->sg[i])) + offset, ubp, cnt);
5443		if (res)
5444			return (-EFAULT);
5445		do_count -= cnt;
5446		st_bp->buffer_bytes += cnt;
5447		ubp += cnt;
5448		offset = 0;
5449	}
5450	if (do_count) {  /* Should never happen */
5451		printk(KERN_WARNING "osst :A: Append_to_buffer overflow (left %d).\n",
5452		       do_count);
5453		return (-EIO);
5454	}
5455	return 0;
5456}
5457
5458
5459/* Move data from the tape buffer to the user buffer. Returns zero (success) or
5460   negative error code. */
5461static int from_buffer(struct osst_buffer *st_bp, char __user *ubp, int do_count)
5462{
5463	int i, cnt, res, offset;
5464
5465	for (i=0, offset=st_bp->read_pointer;
5466	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5467		offset -= st_bp->sg[i].length;
5468	if (i == st_bp->sg_segs) {  /* Should never happen */
5469		printk(KERN_WARNING "osst :A: From_buffer offset overflow.\n");
5470		return (-EIO);
5471	}
5472	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {
5473		cnt = st_bp->sg[i].length - offset < do_count ?
5474		      st_bp->sg[i].length - offset : do_count;
5475		res = copy_to_user(ubp, page_address(sg_page(&st_bp->sg[i])) + offset, cnt);
5476		if (res)
5477			return (-EFAULT);
5478		do_count -= cnt;
5479		st_bp->buffer_bytes -= cnt;
5480		st_bp->read_pointer += cnt;
5481		ubp += cnt;
5482		offset = 0;
5483	}
5484	if (do_count) {  /* Should never happen */
5485		printk(KERN_WARNING "osst :A: From_buffer overflow (left %d).\n", do_count);
5486		return (-EIO);
5487	}
5488	return 0;
5489}
5490
5491/* Sets the tail of the buffer after fill point to zero.
5492   Returns zero (success) or negative error code.        */
5493static int osst_zero_buffer_tail(struct osst_buffer *st_bp)
5494{
5495	int	i, offset, do_count, cnt;
5496
5497	for (i = 0, offset = st_bp->buffer_bytes;
5498	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5499		offset -= st_bp->sg[i].length;
5500	if (i == st_bp->sg_segs) {  /* Should never happen */
5501		printk(KERN_WARNING "osst :A: Zero_buffer offset overflow.\n");
5502		return (-EIO);
5503	}
5504	for (do_count = OS_DATA_SIZE - st_bp->buffer_bytes;
5505	     i < st_bp->sg_segs && do_count > 0; i++) {
5506		cnt = st_bp->sg[i].length - offset < do_count ?
5507		      st_bp->sg[i].length - offset : do_count ;
5508		memset(page_address(sg_page(&st_bp->sg[i])) + offset, 0, cnt);
5509		do_count -= cnt;
5510		offset = 0;
5511	}
5512	if (do_count) {  /* Should never happen */
5513		printk(KERN_WARNING "osst :A: Zero_buffer overflow (left %d).\n", do_count);
5514		return (-EIO);
5515	}
5516	return 0;
5517}
5518
5519/* Copy a osst 32K chunk of memory into the buffer.
5520   Returns zero (success) or negative error code.  */
5521static int osst_copy_to_buffer(struct osst_buffer *st_bp, unsigned char *ptr)
5522{
5523	int	i, cnt, do_count = OS_DATA_SIZE;
5524
5525	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {
5526		cnt = st_bp->sg[i].length < do_count ?
5527		      st_bp->sg[i].length : do_count ;
5528		memcpy(page_address(sg_page(&st_bp->sg[i])), ptr, cnt);
5529		do_count -= cnt;
5530		ptr      += cnt;
5531	}
5532	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */
5533		printk(KERN_WARNING "osst :A: Copy_to_buffer overflow (left %d at sg %d).\n",
5534					 do_count, i);
5535		return (-EIO);
5536	}
5537	return 0;
5538}
5539
5540/* Copy a osst 32K chunk of memory from the buffer.
5541   Returns zero (success) or negative error code.  */
5542static int osst_copy_from_buffer(struct osst_buffer *st_bp, unsigned char *ptr)
5543{
5544	int	i, cnt, do_count = OS_DATA_SIZE;
5545
5546	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {
5547		cnt = st_bp->sg[i].length < do_count ?
5548		      st_bp->sg[i].length : do_count ;
5549		memcpy(ptr, page_address(sg_page(&st_bp->sg[i])), cnt);
5550		do_count -= cnt;
5551		ptr      += cnt;
5552	}
5553	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */
5554		printk(KERN_WARNING "osst :A: Copy_from_buffer overflow (left %d at sg %d).\n",
5555					 do_count, i);
5556		return (-EIO);
5557	}
5558	return 0;
5559}
5560
5561
5562/* Module housekeeping */
5563
5564static void validate_options (void)
5565{
5566  if (max_dev > 0)
5567		osst_max_dev = max_dev;  
5568  if (write_threshold_kbs > 0)
5569		osst_write_threshold = write_threshold_kbs * ST_KILOBYTE;
5570  if (osst_write_threshold > osst_buffer_size)
5571		osst_write_threshold = osst_buffer_size;
5572  if (max_sg_segs >= OSST_FIRST_SG)
5573		osst_max_sg_segs = max_sg_segs;
5574#if DEBUG
5575  printk(OSST_DEB_MSG "osst :D: max tapes %d, write threshold %d, max s/g segs %d.\n",
5576			   osst_max_dev, osst_write_threshold, osst_max_sg_segs);
5577#endif
5578}
5579	
5580#ifndef MODULE
5581/* Set the boot options. Syntax: osst=xxx,yyy,...
5582   where xxx is write threshold in 1024 byte blocks,
5583   and   yyy is number of s/g segments to use. */
5584static int __init osst_setup (char *str)
5585{
5586  int i, ints[5];
5587  char *stp;
5588
5589  stp = get_options(str, ARRAY_SIZE(ints), ints);
5590
5591  if (ints[0] > 0) {
5592	for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
5593		  *parms[i].val = ints[i + 1];
5594  } else {
5595	while (stp != NULL) {
5596		for (i = 0; i < ARRAY_SIZE(parms); i++) {
5597			int len = strlen(parms[i].name);
5598			if (!strncmp(stp, parms[i].name, len) &&
5599			    (*(stp + len) == ':' || *(stp + len) == '=')) {
5600				*parms[i].val =
5601					simple_strtoul(stp + len + 1, NULL, 0);
5602				break;
5603			}
5604		}
5605		if (i >= ARRAY_SIZE(parms))
5606			printk(KERN_INFO "osst :I: Illegal parameter in '%s'\n",
5607			       stp);
5608		stp = strchr(stp, ',');
5609		if (stp)
5610			stp++;
5611	}
5612  }
5613
5614  return 1;
5615}
5616
5617__setup("osst=", osst_setup);
5618
5619#endif
5620
5621static const struct file_operations osst_fops = {
5622	.owner =        THIS_MODULE,
5623	.read =         osst_read,
5624	.write =        osst_write,
5625	.unlocked_ioctl = osst_ioctl,
5626#ifdef CONFIG_COMPAT
5627	.compat_ioctl = osst_compat_ioctl,
5628#endif
5629	.open =         os_scsi_tape_open,
5630	.flush =        os_scsi_tape_flush,
5631	.release =      os_scsi_tape_close,
5632	.llseek =	noop_llseek,
5633};
5634
5635static int osst_supports(struct scsi_device * SDp)
5636{
5637	struct	osst_support_data {
5638		char *vendor;
5639		char *model;
5640		char *rev;
5641		char *driver_hint; /* Name of the correct driver, NULL if unknown */
5642	};
5643
5644static	struct	osst_support_data support_list[] = {
5645		/* {"XXX", "Yy-", "", NULL},  example */
5646		SIGS_FROM_OSST,
5647		{NULL, }};
5648
5649	struct	osst_support_data *rp;
5650
5651	/* We are willing to drive OnStream SC-x0 as well as the
5652	 * 	 * IDE, ParPort, FireWire, USB variants, if accessible by
5653	 * 	 	 * emulation layer (ide-scsi, usb-storage, ...) */
5654
5655	for (rp=&(support_list[0]); rp->vendor != NULL; rp++)
5656		if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
5657		    !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
5658		    !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) 
5659			return 1;
5660	return 0;
5661}
5662
5663/*
5664 * sysfs support for osst driver parameter information
5665 */
5666
5667static ssize_t osst_version_show(struct device_driver *ddd, char *buf)
5668{
5669	return snprintf(buf, PAGE_SIZE, "%s\n", osst_version);
5670}
5671
5672static DRIVER_ATTR(version, S_IRUGO, osst_version_show, NULL);
5673
5674static int osst_create_sysfs_files(struct device_driver *sysfs)
5675{
5676	return driver_create_file(sysfs, &driver_attr_version);
5677}
5678
5679static void osst_remove_sysfs_files(struct device_driver *sysfs)
5680{
5681	driver_remove_file(sysfs, &driver_attr_version);
5682}
5683
5684/*
5685 * sysfs support for accessing ADR header information
5686 */
5687
5688static ssize_t osst_adr_rev_show(struct device *dev,
5689				 struct device_attribute *attr, char *buf)
5690{
5691	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5692	ssize_t l = 0;
5693
5694	if (STp && STp->header_ok && STp->linux_media)
5695		l = snprintf(buf, PAGE_SIZE, "%d.%d\n", STp->header_cache->major_rev, STp->header_cache->minor_rev);
5696	return l;
5697}
5698
5699DEVICE_ATTR(ADR_rev, S_IRUGO, osst_adr_rev_show, NULL);
5700
5701static ssize_t osst_linux_media_version_show(struct device *dev,
5702					     struct device_attribute *attr,
5703					     char *buf)
5704{
5705	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5706	ssize_t l = 0;
5707
5708	if (STp && STp->header_ok && STp->linux_media)
5709		l = snprintf(buf, PAGE_SIZE, "LIN%d\n", STp->linux_media_version);
5710	return l;
5711}
5712
5713DEVICE_ATTR(media_version, S_IRUGO, osst_linux_media_version_show, NULL);
5714
5715static ssize_t osst_capacity_show(struct device *dev,
5716				  struct device_attribute *attr, char *buf)
5717{
5718	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5719	ssize_t l = 0;
5720
5721	if (STp && STp->header_ok && STp->linux_media)
5722		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->capacity);
5723	return l;
5724}
5725
5726DEVICE_ATTR(capacity, S_IRUGO, osst_capacity_show, NULL);
5727
5728static ssize_t osst_first_data_ppos_show(struct device *dev,
5729					 struct device_attribute *attr,
5730					 char *buf)
5731{
5732	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5733	ssize_t l = 0;
5734
5735	if (STp && STp->header_ok && STp->linux_media)
5736		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->first_data_ppos);
5737	return l;
5738}
5739
5740DEVICE_ATTR(BOT_frame, S_IRUGO, osst_first_data_ppos_show, NULL);
5741
5742static ssize_t osst_eod_frame_ppos_show(struct device *dev,
5743					struct device_attribute *attr,
5744					char *buf)
5745{
5746	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5747	ssize_t l = 0;
5748
5749	if (STp && STp->header_ok && STp->linux_media)
5750		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->eod_frame_ppos);
5751	return l;
5752}
5753
5754DEVICE_ATTR(EOD_frame, S_IRUGO, osst_eod_frame_ppos_show, NULL);
5755
5756static ssize_t osst_filemark_cnt_show(struct device *dev,
5757				      struct device_attribute *attr, char *buf)
5758{
5759	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5760	ssize_t l = 0;
5761
5762	if (STp && STp->header_ok && STp->linux_media)
5763		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->filemark_cnt);
5764	return l;
5765}
5766
5767DEVICE_ATTR(file_count, S_IRUGO, osst_filemark_cnt_show, NULL);
5768
5769static struct class *osst_sysfs_class;
5770
5771static int osst_sysfs_init(void)
5772{
5773	osst_sysfs_class = class_create(THIS_MODULE, "onstream_tape");
5774	if (IS_ERR(osst_sysfs_class)) {
5775		printk(KERN_ERR "osst :W: Unable to register sysfs class\n");
5776		return PTR_ERR(osst_sysfs_class);
5777	}
5778
5779	return 0;
5780}
5781
5782static void osst_sysfs_destroy(dev_t dev)
5783{
5784	device_destroy(osst_sysfs_class, dev);
5785}
5786
5787static int osst_sysfs_add(dev_t dev, struct device *device, struct osst_tape * STp, char * name)
5788{
5789	struct device *osst_member;
5790	int err;
5791
5792	osst_member = device_create(osst_sysfs_class, device, dev, STp,
5793				    "%s", name);
5794	if (IS_ERR(osst_member)) {
5795		printk(KERN_WARNING "osst :W: Unable to add sysfs class member %s\n", name);
5796		return PTR_ERR(osst_member);
5797	}
5798
5799	err = device_create_file(osst_member, &dev_attr_ADR_rev);
5800	if (err)
5801		goto err_out;
5802	err = device_create_file(osst_member, &dev_attr_media_version);
5803	if (err)
5804		goto err_out;
5805	err = device_create_file(osst_member, &dev_attr_capacity);
5806	if (err)
5807		goto err_out;
5808	err = device_create_file(osst_member, &dev_attr_BOT_frame);
5809	if (err)
5810		goto err_out;
5811	err = device_create_file(osst_member, &dev_attr_EOD_frame);
5812	if (err)
5813		goto err_out;
5814	err = device_create_file(osst_member, &dev_attr_file_count);
5815	if (err)
5816		goto err_out;
5817
5818	return 0;
5819
5820err_out:
5821	osst_sysfs_destroy(dev);
5822	return err;
5823}
5824
5825static void osst_sysfs_cleanup(void)
5826{
5827	class_destroy(osst_sysfs_class);
5828}
5829
5830/*
5831 * osst startup / cleanup code
5832 */
5833
5834static int osst_probe(struct device *dev)
5835{
5836	struct scsi_device * SDp = to_scsi_device(dev);
5837	struct osst_tape   * tpnt;
5838	struct st_modedef  * STm;
5839	struct st_partstat * STps;
5840	struct osst_buffer * buffer;
5841	struct gendisk	   * drive;
5842	int		     i, dev_num, err = -ENODEV;
5843
5844	if (SDp->type != TYPE_TAPE || !osst_supports(SDp))
5845		return -ENODEV;
5846
5847	drive = alloc_disk(1);
5848	if (!drive) {
5849		printk(KERN_ERR "osst :E: Out of memory. Device not attached.\n");
5850		return -ENODEV;
5851	}
5852
5853	/* if this is the first attach, build the infrastructure */
5854	write_lock(&os_scsi_tapes_lock);
5855	if (os_scsi_tapes == NULL) {
5856		os_scsi_tapes = kmalloc(osst_max_dev * sizeof(struct osst_tape *), GFP_ATOMIC);
5857		if (os_scsi_tapes == NULL) {
5858			write_unlock(&os_scsi_tapes_lock);
5859			printk(KERN_ERR "osst :E: Unable to allocate array for OnStream SCSI tapes.\n");
5860			goto out_put_disk;
5861		}
5862		for (i=0; i < osst_max_dev; ++i) os_scsi_tapes[i] = NULL;
5863	}
5864	
5865	if (osst_nr_dev >= osst_max_dev) {
5866		write_unlock(&os_scsi_tapes_lock);
5867		printk(KERN_ERR "osst :E: Too many tape devices (max. %d).\n", osst_max_dev);
5868		goto out_put_disk;
5869	}
5870
5871	/* find a free minor number */
5872	for (i = 0; i < osst_max_dev && os_scsi_tapes[i]; i++)
5873		;
5874	if(i >= osst_max_dev) panic ("Scsi_devices corrupt (osst)");
5875	dev_num = i;
5876
5877	/* allocate a struct osst_tape for this device */
5878	tpnt = kzalloc(sizeof(struct osst_tape), GFP_ATOMIC);
5879	if (!tpnt) {
5880		write_unlock(&os_scsi_tapes_lock);
5881		printk(KERN_ERR "osst :E: Can't allocate device descriptor, device not attached.\n");
5882		goto out_put_disk;
5883	}
5884
5885	/* allocate a buffer for this device */
5886	i = SDp->host->sg_tablesize;
5887	if (osst_max_sg_segs < i)
5888		i = osst_max_sg_segs;
5889	buffer = new_tape_buffer(1, SDp->host->unchecked_isa_dma, i);
5890	if (buffer == NULL) {
5891		write_unlock(&os_scsi_tapes_lock);
5892		printk(KERN_ERR "osst :E: Unable to allocate a tape buffer, device not attached.\n");
5893		kfree(tpnt);
5894		goto out_put_disk;
5895	}
5896	os_scsi_tapes[dev_num] = tpnt;
5897	tpnt->buffer = buffer;
5898	tpnt->device = SDp;
5899	drive->private_data = &tpnt->driver;
5900	sprintf(drive->disk_name, "osst%d", dev_num);
5901	tpnt->driver = &osst_template;
5902	tpnt->drive = drive;
5903	tpnt->in_use = 0;
5904	tpnt->capacity = 0xfffff;
5905	tpnt->dirty = 0;
5906	tpnt->drv_buffer = 1;  /* Try buffering if no mode sense */
5907	tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
5908	tpnt->density = 0;
5909	tpnt->do_auto_lock = OSST_AUTO_LOCK;
5910	tpnt->can_bsr = OSST_IN_FILE_POS;
5911	tpnt->can_partitions = 0;
5912	tpnt->two_fm = OSST_TWO_FM;
5913	tpnt->fast_mteom = OSST_FAST_MTEOM;
5914	tpnt->scsi2_logical = OSST_SCSI2LOGICAL; /* FIXME */
5915	tpnt->write_threshold = osst_write_threshold;
5916	tpnt->default_drvbuffer = 0xff; /* No forced buffering */
5917	tpnt->partition = 0;
5918	tpnt->new_partition = 0;
5919	tpnt->nbr_partitions = 0;
5920	tpnt->min_block = 512;
5921	tpnt->max_block = OS_DATA_SIZE;
5922	tpnt->timeout = OSST_TIMEOUT;
5923	tpnt->long_timeout = OSST_LONG_TIMEOUT;
5924
5925	/* Recognize OnStream tapes */
5926	/* We don't need to test for OnStream, as this has been done in detect () */
5927	tpnt->os_fw_rev = osst_parse_firmware_rev (SDp->rev);
5928	tpnt->omit_blklims = 1;
5929
5930	tpnt->poll = (strncmp(SDp->model, "DI-", 3) == 0) || 
5931		     (strncmp(SDp->model, "FW-", 3) == 0) || OSST_FW_NEED_POLL(tpnt->os_fw_rev,SDp);
5932	tpnt->frame_in_buffer = 0;
5933	tpnt->header_ok = 0;
5934	tpnt->linux_media = 0;
5935	tpnt->header_cache = NULL;
5936
5937	for (i=0; i < ST_NBR_MODES; i++) {
5938		STm = &(tpnt->modes[i]);
5939		STm->defined = 0;
5940		STm->sysv = OSST_SYSV;
5941		STm->defaults_for_writes = 0;
5942		STm->do_async_writes = OSST_ASYNC_WRITES;
5943		STm->do_buffer_writes = OSST_BUFFER_WRITES;
5944		STm->do_read_ahead = OSST_READ_AHEAD;
5945		STm->default_compression = ST_DONT_TOUCH;
5946		STm->default_blksize = 512;
5947		STm->default_density = (-1);  /* No forced density */
5948	}
5949
5950	for (i=0; i < ST_NBR_PARTITIONS; i++) {
5951		STps = &(tpnt->ps[i]);
5952		STps->rw = ST_IDLE;
5953		STps->eof = ST_NOEOF;
5954		STps->at_sm = 0;
5955		STps->last_block_valid = 0;
5956		STps->drv_block = (-1);
5957		STps->drv_file = (-1);
5958	}
5959
5960	tpnt->current_mode = 0;
5961	tpnt->modes[0].defined = 1;
5962	tpnt->modes[2].defined = 1;
5963	tpnt->density_changed = tpnt->compression_changed = tpnt->blksize_changed = 0;
5964
5965	mutex_init(&tpnt->lock);
5966	osst_nr_dev++;
5967	write_unlock(&os_scsi_tapes_lock);
5968
5969	{
5970		char name[8];
5971
5972		/*  Rewind entry  */
5973		err = osst_sysfs_add(MKDEV(OSST_MAJOR, dev_num), dev, tpnt, tape_name(tpnt));
5974		if (err)
5975			goto out_free_buffer;
5976
5977		/*  No-rewind entry  */
5978		snprintf(name, 8, "%s%s", "n", tape_name(tpnt));
5979		err = osst_sysfs_add(MKDEV(OSST_MAJOR, dev_num + 128), dev, tpnt, name);
5980		if (err)
5981			goto out_free_sysfs1;
5982	}
5983
5984	sdev_printk(KERN_INFO, SDp,
5985		"osst :I: Attached OnStream %.5s tape as %s\n",
5986		SDp->model, tape_name(tpnt));
5987
5988	return 0;
5989
5990out_free_sysfs1:
5991	osst_sysfs_destroy(MKDEV(OSST_MAJOR, dev_num));
5992out_free_buffer:
5993	kfree(buffer);
5994out_put_disk:
5995        put_disk(drive);
5996        return err;
5997};
5998
5999static int osst_remove(struct device *dev)
6000{
6001	struct scsi_device * SDp = to_scsi_device(dev);
6002	struct osst_tape * tpnt;
6003	int i;
6004
6005	if ((SDp->type != TYPE_TAPE) || (osst_nr_dev <= 0))
6006		return 0;
6007
6008	write_lock(&os_scsi_tapes_lock);
6009	for(i=0; i < osst_max_dev; i++) {
6010		if((tpnt = os_scsi_tapes[i]) && (tpnt->device == SDp)) {
6011			osst_sysfs_destroy(MKDEV(OSST_MAJOR, i));
6012			osst_sysfs_destroy(MKDEV(OSST_MAJOR, i+128));
6013			tpnt->device = NULL;
6014			put_disk(tpnt->drive);
6015			os_scsi_tapes[i] = NULL;
6016			osst_nr_dev--;
6017			write_unlock(&os_scsi_tapes_lock);
6018			vfree(tpnt->header_cache);
6019			if (tpnt->buffer) {
6020				normalize_buffer(tpnt->buffer);
6021				kfree(tpnt->buffer);
6022			}
6023			kfree(tpnt);
6024			return 0;
6025		}
6026	}
6027	write_unlock(&os_scsi_tapes_lock);
6028	return 0;
6029}
6030
6031static int __init init_osst(void) 
6032{
6033	int err;
6034
6035	printk(KERN_INFO "osst :I: Tape driver with OnStream support version %s\nosst :I: %s\n", osst_version, cvsid);
6036
6037	validate_options();
6038
6039	err = osst_sysfs_init();
6040	if (err)
6041		return err;
6042
6043	err = register_chrdev(OSST_MAJOR, "osst", &osst_fops);
6044	if (err < 0) {
6045		printk(KERN_ERR "osst :E: Unable to register major %d for OnStream tapes\n", OSST_MAJOR);
6046		goto err_out;
6047	}
6048
6049	err = scsi_register_driver(&osst_template.gendrv);
6050	if (err)
6051		goto err_out_chrdev;
6052
6053	err = osst_create_sysfs_files(&osst_template.gendrv);
6054	if (err)
6055		goto err_out_scsidrv;
6056
6057	return 0;
6058
6059err_out_scsidrv:
6060	scsi_unregister_driver(&osst_template.gendrv);
6061err_out_chrdev:
6062	unregister_chrdev(OSST_MAJOR, "osst");
6063err_out:
6064	osst_sysfs_cleanup();
6065	return err;
6066}
6067
6068static void __exit exit_osst (void)
6069{
6070	int i;
6071	struct osst_tape * STp;
6072
6073	osst_remove_sysfs_files(&osst_template.gendrv);
6074	scsi_unregister_driver(&osst_template.gendrv);
6075	unregister_chrdev(OSST_MAJOR, "osst");
6076	osst_sysfs_cleanup();
6077
6078	if (os_scsi_tapes) {
6079		for (i=0; i < osst_max_dev; ++i) {
6080			if (!(STp = os_scsi_tapes[i])) continue;
6081			/* This is defensive, supposed to happen during detach */
6082			vfree(STp->header_cache);
6083			if (STp->buffer) {
6084				normalize_buffer(STp->buffer);
6085				kfree(STp->buffer);
6086			}
6087			put_disk(STp->drive);
6088			kfree(STp);
6089		}
6090		kfree(os_scsi_tapes);
6091	}
6092	printk(KERN_INFO "osst :I: Unloaded.\n");
6093}
6094
6095module_init(init_osst);
6096module_exit(exit_osst);
v4.17
   1/*
   2  SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
   3  file Documentation/scsi/st.txt for more information.
   4
   5  History:
   6
   7  OnStream SCSI Tape support (osst) cloned from st.c by
   8  Willem Riede (osst@riede.org) Feb 2000
   9  Fixes ... Kurt Garloff <garloff@suse.de> Mar 2000
  10
  11  Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
  12  Contribution and ideas from several people including (in alphabetical
  13  order) Klaus Ehrenfried, Wolfgang Denk, Steve Hirsch, Andreas Koppenh"ofer,
  14  Michael Leodolter, Eyal Lebedinsky, J"org Weule, and Eric Youngdale.
  15
  16  Copyright 1992 - 2002 Kai Makisara / 2000 - 2006 Willem Riede
  17	 email osst@riede.org
  18
  19  $Header: /cvsroot/osst/Driver/osst.c,v 1.73 2005/01/01 21:13:34 wriede Exp $
  20
  21  Microscopic alterations - Rik Ling, 2000/12/21
  22  Last st.c sync: Tue Oct 15 22:01:04 2002 by makisara
  23  Some small formal changes - aeb, 950809
  24*/
  25
  26static const char * cvsid = "$Id: osst.c,v 1.73 2005/01/01 21:13:34 wriede Exp $";
  27static const char * osst_version = "0.99.4";
  28
  29/* The "failure to reconnect" firmware bug */
  30#define OSST_FW_NEED_POLL_MIN 10601 /*(107A)*/
  31#define OSST_FW_NEED_POLL_MAX 10704 /*(108D)*/
  32#define OSST_FW_NEED_POLL(x,d) ((x) >= OSST_FW_NEED_POLL_MIN && (x) <= OSST_FW_NEED_POLL_MAX && d->host->this_id != 7)
  33
  34#include <linux/module.h>
  35
  36#include <linux/fs.h>
  37#include <linux/kernel.h>
  38#include <linux/sched/signal.h>
  39#include <linux/proc_fs.h>
  40#include <linux/mm.h>
  41#include <linux/slab.h>
  42#include <linux/init.h>
  43#include <linux/string.h>
  44#include <linux/errno.h>
  45#include <linux/mtio.h>
  46#include <linux/ioctl.h>
  47#include <linux/fcntl.h>
  48#include <linux/spinlock.h>
  49#include <linux/vmalloc.h>
  50#include <linux/blkdev.h>
  51#include <linux/moduleparam.h>
  52#include <linux/delay.h>
  53#include <linux/jiffies.h>
  54#include <linux/mutex.h>
  55#include <linux/uaccess.h>
  56#include <asm/dma.h>
 
  57
  58/* The driver prints some debugging information on the console if DEBUG
  59   is defined and non-zero. */
  60#define DEBUG 0
  61
  62/* The message level for the debug messages is currently set to KERN_NOTICE
  63   so that people can easily see the messages. Later when the debugging messages
  64   in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
  65#define OSST_DEB_MSG  KERN_NOTICE
  66
  67#include <scsi/scsi.h>
  68#include <scsi/scsi_dbg.h>
  69#include <scsi/scsi_device.h>
  70#include <scsi/scsi_driver.h>
  71#include <scsi/scsi_eh.h>
  72#include <scsi/scsi_host.h>
  73#include <scsi/scsi_ioctl.h>
  74
  75#define ST_KILOBYTE 1024
  76
  77#include "st.h"
  78#include "osst.h"
  79#include "osst_options.h"
  80#include "osst_detect.h"
  81
  82static DEFINE_MUTEX(osst_int_mutex);
  83static int max_dev = 0;
  84static int write_threshold_kbs = 0;
  85static int max_sg_segs = 0;
  86
  87#ifdef MODULE
  88MODULE_AUTHOR("Willem Riede");
  89MODULE_DESCRIPTION("OnStream {DI-|FW-|SC-|USB}{30|50} Tape Driver");
  90MODULE_LICENSE("GPL");
  91MODULE_ALIAS_CHARDEV_MAJOR(OSST_MAJOR);
  92MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
  93
  94module_param(max_dev, int, 0444);
  95MODULE_PARM_DESC(max_dev, "Maximum number of OnStream Tape Drives to attach (4)");
  96
  97module_param(write_threshold_kbs, int, 0644);
  98MODULE_PARM_DESC(write_threshold_kbs, "Asynchronous write threshold (KB; 32)");
  99
 100module_param(max_sg_segs, int, 0644);
 101MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (9)");
 102#else
 103static struct osst_dev_parm {
 104       char   *name;
 105       int    *val;
 106} parms[] __initdata = {
 107       { "max_dev",             &max_dev             },
 108       { "write_threshold_kbs", &write_threshold_kbs },
 109       { "max_sg_segs",         &max_sg_segs         }
 110};
 111#endif
 112
 113/* Some default definitions have been moved to osst_options.h */
 114#define OSST_BUFFER_SIZE (OSST_BUFFER_BLOCKS * ST_KILOBYTE)
 115#define OSST_WRITE_THRESHOLD (OSST_WRITE_THRESHOLD_BLOCKS * ST_KILOBYTE)
 116
 117/* The buffer size should fit into the 24 bits for length in the
 118   6-byte SCSI read and write commands. */
 119#if OSST_BUFFER_SIZE >= (2 << 24 - 1)
 120#error "Buffer size should not exceed (2 << 24 - 1) bytes!"
 121#endif
 122
 123#if DEBUG
 124static int debugging = 1;
 125/* uncomment define below to test error recovery */
 126// #define OSST_INJECT_ERRORS 1 
 127#endif
 128
 129/* Do not retry! The drive firmware already retries when appropriate,
 130   and when it tries to tell us something, we had better listen... */
 131#define MAX_RETRIES 0
 132
 133#define NO_TAPE  NOT_READY
 134
 135#define OSST_WAIT_POSITION_COMPLETE   (HZ > 200 ? HZ / 200 : 1)
 136#define OSST_WAIT_WRITE_COMPLETE      (HZ / 12)
 137#define OSST_WAIT_LONG_WRITE_COMPLETE (HZ / 2)
 138	
 139#define OSST_TIMEOUT (200 * HZ)
 140#define OSST_LONG_TIMEOUT (1800 * HZ)
 141
 142#define TAPE_NR(x) (iminor(x) & ~(-1 << ST_MODE_SHIFT))
 143#define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
 144#define TAPE_REWIND(x) ((iminor(x) & 0x80) == 0)
 145#define TAPE_IS_RAW(x) (TAPE_MODE(x) & (ST_NBR_MODES >> 1))
 146
 147/* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
 148   24 bits) */
 149#define SET_DENS_AND_BLK 0x10001
 150
 151static int osst_buffer_size       = OSST_BUFFER_SIZE;
 152static int osst_write_threshold   = OSST_WRITE_THRESHOLD;
 153static int osst_max_sg_segs       = OSST_MAX_SG;
 154static int osst_max_dev           = OSST_MAX_TAPES;
 155static int osst_nr_dev;
 156
 157static struct osst_tape **os_scsi_tapes = NULL;
 158static DEFINE_RWLOCK(os_scsi_tapes_lock);
 159
 160static int modes_defined = 0;
 161
 162static struct osst_buffer *new_tape_buffer(int, int, int);
 163static int enlarge_buffer(struct osst_buffer *, int);
 164static void normalize_buffer(struct osst_buffer *);
 165static int append_to_buffer(const char __user *, struct osst_buffer *, int);
 166static int from_buffer(struct osst_buffer *, char __user *, int);
 167static int osst_zero_buffer_tail(struct osst_buffer *);
 168static int osst_copy_to_buffer(struct osst_buffer *, unsigned char *);
 169static int osst_copy_from_buffer(struct osst_buffer *, unsigned char *);
 170
 171static int osst_probe(struct device *);
 172static int osst_remove(struct device *);
 173
 174static struct scsi_driver osst_template = {
 
 175	.gendrv = {
 176		.name		=  "osst",
 177		.owner		= THIS_MODULE,
 178		.probe		= osst_probe,
 179		.remove		= osst_remove,
 180	}
 181};
 182
 183static int osst_int_ioctl(struct osst_tape *STp, struct osst_request ** aSRpnt,
 184			    unsigned int cmd_in, unsigned long arg);
 185
 186static int osst_set_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt, int frame, int skip);
 187
 188static int osst_get_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt);
 189
 190static int osst_flush_write_buffer(struct osst_tape *STp, struct osst_request ** aSRpnt);
 191
 192static int osst_write_error_recovery(struct osst_tape * STp, struct osst_request ** aSRpnt, int pending);
 193
 194static inline char *tape_name(struct osst_tape *tape)
 195{
 196	return tape->drive->disk_name;
 197}
 198
 199/* Routines that handle the interaction with mid-layer SCSI routines */
 200
 201
 202/* Normalize Sense */
 203static void osst_analyze_sense(struct osst_request *SRpnt, struct st_cmdstatus *s)
 204{
 205	const u8 *ucp;
 206	const u8 *sense = SRpnt->sense;
 207
 208	s->have_sense = scsi_normalize_sense(SRpnt->sense,
 209				SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
 210	s->flags = 0;
 211
 212	if (s->have_sense) {
 213		s->deferred = 0;
 214		s->remainder_valid =
 215			scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
 216		switch (sense[0] & 0x7f) {
 217		case 0x71:
 218			s->deferred = 1;
 219		case 0x70:
 220			s->fixed_format = 1;
 221			s->flags = sense[2] & 0xe0;
 222			break;
 223		case 0x73:
 224			s->deferred = 1;
 225		case 0x72:
 226			s->fixed_format = 0;
 227			ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
 228			s->flags = ucp ? (ucp[3] & 0xe0) : 0;
 229			break;
 230		}
 231	}
 232}
 233
 234/* Convert the result to success code */
 235static int osst_chk_result(struct osst_tape * STp, struct osst_request * SRpnt)
 236{
 237	char *name = tape_name(STp);
 238	int result = SRpnt->result;
 239	u8 * sense = SRpnt->sense, scode;
 240#if DEBUG
 241	const char *stp;
 242#endif
 243	struct st_cmdstatus *cmdstatp;
 244
 245	if (!result)
 246		return 0;
 247
 248	cmdstatp = &STp->buffer->cmdstat;
 249	osst_analyze_sense(SRpnt, cmdstatp);
 250
 251	if (cmdstatp->have_sense)
 252		scode = STp->buffer->cmdstat.sense_hdr.sense_key;
 253	else
 254		scode = 0;
 255#if DEBUG
 256	if (debugging) {
 257		printk(OSST_DEB_MSG "%s:D: Error: %x, cmd: %x %x %x %x %x %x\n",
 258		   name, result,
 259		   SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
 260		   SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
 261		if (scode) printk(OSST_DEB_MSG "%s:D: Sense: %02x, ASC: %02x, ASCQ: %02x\n",
 262				  name, scode, sense[12], sense[13]);
 263		if (cmdstatp->have_sense)
 264			__scsi_print_sense(STp->device, name,
 265					   SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
 266	}
 267	else
 268#endif
 269	if (cmdstatp->have_sense && (
 270		 scode != NO_SENSE &&
 271		 scode != RECOVERED_ERROR &&
 272/*      	 scode != UNIT_ATTENTION && */
 273		 scode != BLANK_CHECK &&
 274		 scode != VOLUME_OVERFLOW &&
 275		 SRpnt->cmd[0] != MODE_SENSE &&
 276		 SRpnt->cmd[0] != TEST_UNIT_READY)) { /* Abnormal conditions for tape */
 277		if (cmdstatp->have_sense) {
 278			printk(KERN_WARNING "%s:W: Command with sense data:\n", name);
 279			__scsi_print_sense(STp->device, name,
 280					   SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
 281		}
 282		else {
 283			static	int	notyetprinted = 1;
 284
 285			printk(KERN_WARNING
 286			     "%s:W: Warning %x (driver bt 0x%x, host bt 0x%x).\n",
 287			     name, result, driver_byte(result),
 288			     host_byte(result));
 289			if (notyetprinted) {
 290				notyetprinted = 0;
 291				printk(KERN_INFO
 292					"%s:I: This warning may be caused by your scsi controller,\n", name);
 293				printk(KERN_INFO
 294					"%s:I: it has been reported with some Buslogic cards.\n", name);
 295			}
 296		}
 297	}
 298	STp->pos_unknown |= STp->device->was_reset;
 299
 300	if (cmdstatp->have_sense && scode == RECOVERED_ERROR) {
 301		STp->recover_count++;
 302		STp->recover_erreg++;
 303#if DEBUG
 304		if (debugging) {
 305			if (SRpnt->cmd[0] == READ_6)
 306				stp = "read";
 307			else if (SRpnt->cmd[0] == WRITE_6)
 308				stp = "write";
 309			else
 310				stp = "ioctl";
 311			printk(OSST_DEB_MSG "%s:D: Recovered %s error (%d).\n", name, stp,
 312					     STp->recover_count);
 313		}
 314#endif
 315		if ((sense[2] & 0xe0) == 0)
 316			return 0;
 317	}
 318	return (-EIO);
 319}
 320
 321
 322/* Wakeup from interrupt */
 323static void osst_end_async(struct request *req, blk_status_t status)
 324{
 325	struct scsi_request *rq = scsi_req(req);
 326	struct osst_request *SRpnt = req->end_io_data;
 327	struct osst_tape *STp = SRpnt->stp;
 328	struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
 329
 330	STp->buffer->cmdstat.midlevel_result = SRpnt->result = rq->result;
 331#if DEBUG
 332	STp->write_pending = 0;
 333#endif
 334	if (rq->sense_len)
 335		memcpy(SRpnt->sense, rq->sense, SCSI_SENSE_BUFFERSIZE);
 336	if (SRpnt->waiting)
 337		complete(SRpnt->waiting);
 338
 339	if (SRpnt->bio) {
 340		kfree(mdata->pages);
 341		blk_rq_unmap_user(SRpnt->bio);
 342	}
 343
 344	__blk_put_request(req->q, req);
 345}
 346
 347/* osst_request memory management */
 348static struct osst_request *osst_allocate_request(void)
 349{
 350	return kzalloc(sizeof(struct osst_request), GFP_KERNEL);
 351}
 352
 353static void osst_release_request(struct osst_request *streq)
 354{
 355	kfree(streq);
 356}
 357
 358static int osst_execute(struct osst_request *SRpnt, const unsigned char *cmd,
 359			int cmd_len, int data_direction, void *buffer, unsigned bufflen,
 360			int use_sg, int timeout, int retries)
 361{
 362	struct request *req;
 363	struct scsi_request *rq;
 364	struct page **pages = NULL;
 365	struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
 366
 367	int err = 0;
 368	int write = (data_direction == DMA_TO_DEVICE);
 369
 370	req = blk_get_request(SRpnt->stp->device->request_queue,
 371			write ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, GFP_KERNEL);
 372	if (IS_ERR(req))
 373		return DRIVER_ERROR << 24;
 374
 375	rq = scsi_req(req);
 376	req->rq_flags |= RQF_QUIET;
 377
 378	SRpnt->bio = NULL;
 379
 380	if (use_sg) {
 381		struct scatterlist *sg, *sgl = (struct scatterlist *)buffer;
 382		int i;
 383
 384		pages = kzalloc(use_sg * sizeof(struct page *), GFP_KERNEL);
 385		if (!pages)
 386			goto free_req;
 387
 388		for_each_sg(sgl, sg, use_sg, i)
 389			pages[i] = sg_page(sg);
 390
 391		mdata->null_mapped = 1;
 392
 393		mdata->page_order = get_order(sgl[0].length);
 394		mdata->nr_entries =
 395			DIV_ROUND_UP(bufflen, PAGE_SIZE << mdata->page_order);
 396		mdata->offset = 0;
 397
 398		err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen, GFP_KERNEL);
 399		if (err) {
 400			kfree(pages);
 401			goto free_req;
 402		}
 403		SRpnt->bio = req->bio;
 404		mdata->pages = pages;
 405
 406	} else if (bufflen) {
 407		err = blk_rq_map_kern(req->q, req, buffer, bufflen, GFP_KERNEL);
 408		if (err)
 409			goto free_req;
 410	}
 411
 412	rq->cmd_len = cmd_len;
 413	memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
 414	memcpy(rq->cmd, cmd, rq->cmd_len);
 
 
 415	req->timeout = timeout;
 416	rq->retries = retries;
 417	req->end_io_data = SRpnt;
 418
 419	blk_execute_rq_nowait(req->q, NULL, req, 1, osst_end_async);
 420	return 0;
 421free_req:
 422	blk_put_request(req);
 423	return DRIVER_ERROR << 24;
 424}
 425
 426/* Do the scsi command. Waits until command performed if do_wait is true.
 427   Otherwise osst_write_behind_check() is used to check that the command
 428   has finished. */
 429static	struct osst_request * osst_do_scsi(struct osst_request *SRpnt, struct osst_tape *STp, 
 430	unsigned char *cmd, int bytes, int direction, int timeout, int retries, int do_wait)
 431{
 432	unsigned char *bp;
 433	unsigned short use_sg;
 434#ifdef OSST_INJECT_ERRORS
 435	static   int   inject = 0;
 436	static   int   repeat = 0;
 437#endif
 438	struct completion *waiting;
 439
 440	/* if async, make sure there's no command outstanding */
 441	if (!do_wait && ((STp->buffer)->last_SRpnt)) {
 442		printk(KERN_ERR "%s: Async command already active.\n",
 443		       tape_name(STp));
 444		if (signal_pending(current))
 445			(STp->buffer)->syscall_result = (-EINTR);
 446		else
 447			(STp->buffer)->syscall_result = (-EBUSY);
 448		return NULL;
 449	}
 450
 451	if (SRpnt == NULL) {
 452		SRpnt = osst_allocate_request();
 453		if (SRpnt == NULL) {
 454			printk(KERN_ERR "%s: Can't allocate SCSI request.\n",
 455				     tape_name(STp));
 456			if (signal_pending(current))
 457				(STp->buffer)->syscall_result = (-EINTR);
 458			else
 459				(STp->buffer)->syscall_result = (-EBUSY);
 460			return NULL;
 461		}
 462		SRpnt->stp = STp;
 463	}
 464
 465	/* If async IO, set last_SRpnt. This ptr tells write_behind_check
 466	   which IO is outstanding. It's nulled out when the IO completes. */
 467	if (!do_wait)
 468		(STp->buffer)->last_SRpnt = SRpnt;
 469
 470	waiting = &STp->wait;
 471	init_completion(waiting);
 472	SRpnt->waiting = waiting;
 473
 474	use_sg = (bytes > STp->buffer->sg[0].length) ? STp->buffer->use_sg : 0;
 475	if (use_sg) {
 476		bp = (char *)&(STp->buffer->sg[0]);
 477		if (STp->buffer->sg_segs < use_sg)
 478			use_sg = STp->buffer->sg_segs;
 479	}
 480	else
 481		bp = (STp->buffer)->b_data;
 482
 483	memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
 484	STp->buffer->cmdstat.have_sense = 0;
 485	STp->buffer->syscall_result = 0;
 486
 487	if (osst_execute(SRpnt, cmd, COMMAND_SIZE(cmd[0]), direction, bp, bytes,
 488			 use_sg, timeout, retries))
 489		/* could not allocate the buffer or request was too large */
 490		(STp->buffer)->syscall_result = (-EBUSY);
 491	else if (do_wait) {
 492		wait_for_completion(waiting);
 493		SRpnt->waiting = NULL;
 494		STp->buffer->syscall_result = osst_chk_result(STp, SRpnt);
 495#ifdef OSST_INJECT_ERRORS
 496		if (STp->buffer->syscall_result == 0 &&
 497		    cmd[0] == READ_6 &&
 498		    cmd[4] && 
 499		    ( (++ inject % 83) == 29  ||
 500		      (STp->first_frame_position == 240 
 501			         /* or STp->read_error_frame to fail again on the block calculated above */ &&
 502				 ++repeat < 3))) {
 503			printk(OSST_DEB_MSG "%s:D: Injecting read error\n", tape_name(STp));
 504			STp->buffer->last_result_fatal = 1;
 505		}
 506#endif
 507	}
 508	return SRpnt;
 509}
 510
 511
 512/* Handle the write-behind checking (downs the semaphore) */
 513static void osst_write_behind_check(struct osst_tape *STp)
 514{
 515	struct osst_buffer * STbuffer;
 516
 517	STbuffer = STp->buffer;
 518
 519#if DEBUG
 520	if (STp->write_pending)
 521		STp->nbr_waits++;
 522	else
 523		STp->nbr_finished++;
 524#endif
 525	wait_for_completion(&(STp->wait));
 526	STp->buffer->last_SRpnt->waiting = NULL;
 527
 528	STp->buffer->syscall_result = osst_chk_result(STp, STp->buffer->last_SRpnt);
 529
 530	if (STp->buffer->syscall_result)
 531		STp->buffer->syscall_result =
 532			osst_write_error_recovery(STp, &(STp->buffer->last_SRpnt), 1);
 533	else
 534		STp->first_frame_position++;
 535
 536	osst_release_request(STp->buffer->last_SRpnt);
 537
 538	if (STbuffer->writing < STbuffer->buffer_bytes)
 539		printk(KERN_WARNING "osst :A: write_behind_check: something left in buffer!\n");
 540
 541	STbuffer->last_SRpnt = NULL;
 542	STbuffer->buffer_bytes -= STbuffer->writing;
 543	STbuffer->writing = 0;
 544
 545	return;
 546}
 547
 548
 549
 550/* Onstream specific Routines */
 551/*
 552 * Initialize the OnStream AUX
 553 */
 554static void osst_init_aux(struct osst_tape * STp, int frame_type, int frame_seq_number,
 555					 int logical_blk_num, int blk_sz, int blk_cnt)
 556{
 557	os_aux_t       *aux = STp->buffer->aux;
 558	os_partition_t *par = &aux->partition;
 559	os_dat_t       *dat = &aux->dat;
 560
 561	if (STp->raw) return;
 562
 563	memset(aux, 0, sizeof(*aux));
 564	aux->format_id = htonl(0);
 565	memcpy(aux->application_sig, "LIN4", 4);
 566	aux->hdwr = htonl(0);
 567	aux->frame_type = frame_type;
 568
 569	switch (frame_type) {
 570	  case	OS_FRAME_TYPE_HEADER:
 571		aux->update_frame_cntr    = htonl(STp->update_frame_cntr);
 572		par->partition_num        = OS_CONFIG_PARTITION;
 573		par->par_desc_ver         = OS_PARTITION_VERSION;
 574		par->wrt_pass_cntr        = htons(0xffff);
 575		/* 0-4 = reserved, 5-9 = header, 2990-2994 = header, 2995-2999 = reserved */
 576		par->first_frame_ppos     = htonl(0);
 577		par->last_frame_ppos      = htonl(0xbb7);
 578		aux->frame_seq_num        = htonl(0);
 579		aux->logical_blk_num_high = htonl(0);
 580		aux->logical_blk_num      = htonl(0);
 581		aux->next_mark_ppos       = htonl(STp->first_mark_ppos);
 582		break;
 583	  case	OS_FRAME_TYPE_DATA:
 584	  case	OS_FRAME_TYPE_MARKER:
 585		dat->dat_sz = 8;
 586		dat->reserved1 = 0;
 587		dat->entry_cnt = 1;
 588		dat->reserved3 = 0;
 589		dat->dat_list[0].blk_sz   = htonl(blk_sz);
 590		dat->dat_list[0].blk_cnt  = htons(blk_cnt);
 591		dat->dat_list[0].flags    = frame_type==OS_FRAME_TYPE_MARKER?
 592							OS_DAT_FLAGS_MARK:OS_DAT_FLAGS_DATA;
 593		dat->dat_list[0].reserved = 0;
 594	  case	OS_FRAME_TYPE_EOD:
 595		aux->update_frame_cntr    = htonl(0);
 596		par->partition_num        = OS_DATA_PARTITION;
 597		par->par_desc_ver         = OS_PARTITION_VERSION;
 598		par->wrt_pass_cntr        = htons(STp->wrt_pass_cntr);
 599		par->first_frame_ppos     = htonl(STp->first_data_ppos);
 600		par->last_frame_ppos      = htonl(STp->capacity);
 601		aux->frame_seq_num        = htonl(frame_seq_number);
 602		aux->logical_blk_num_high = htonl(0);
 603		aux->logical_blk_num      = htonl(logical_blk_num);
 604		break;
 605	  default: ; /* probably FILL */
 606	}
 607	aux->filemark_cnt = htonl(STp->filemark_cnt);
 608	aux->phys_fm = htonl(0xffffffff);
 609	aux->last_mark_ppos = htonl(STp->last_mark_ppos);
 610	aux->last_mark_lbn  = htonl(STp->last_mark_lbn);
 611}
 612
 613/*
 614 * Verify that we have the correct tape frame
 615 */
 616static int osst_verify_frame(struct osst_tape * STp, int frame_seq_number, int quiet)
 617{
 618	char               * name = tape_name(STp);
 619	os_aux_t           * aux  = STp->buffer->aux;
 620	os_partition_t     * par  = &(aux->partition);
 621	struct st_partstat * STps = &(STp->ps[STp->partition]);
 622	unsigned int	     blk_cnt, blk_sz, i;
 623
 624	if (STp->raw) {
 625		if (STp->buffer->syscall_result) {
 626			for (i=0; i < STp->buffer->sg_segs; i++)
 627				memset(page_address(sg_page(&STp->buffer->sg[i])),
 628				       0, STp->buffer->sg[i].length);
 629			strcpy(STp->buffer->b_data, "READ ERROR ON FRAME");
 630                } else
 631			STp->buffer->buffer_bytes = OS_FRAME_SIZE;
 632		return 1;
 633	}
 634	if (STp->buffer->syscall_result) {
 635#if DEBUG
 636		printk(OSST_DEB_MSG "%s:D: Skipping frame, read error\n", name);
 637#endif
 638		return 0;
 639	}
 640	if (ntohl(aux->format_id) != 0) {
 641#if DEBUG
 642		printk(OSST_DEB_MSG "%s:D: Skipping frame, format_id %u\n", name, ntohl(aux->format_id));
 643#endif
 644		goto err_out;
 645	}
 646	if (memcmp(aux->application_sig, STp->application_sig, 4) != 0 &&
 647	    (memcmp(aux->application_sig, "LIN3", 4) != 0 || STp->linux_media_version != 4)) {
 648#if DEBUG
 649		printk(OSST_DEB_MSG "%s:D: Skipping frame, incorrect application signature\n", name);
 650#endif
 651		goto err_out;
 652	}
 653	if (par->partition_num != OS_DATA_PARTITION) {
 654		if (!STp->linux_media || STp->linux_media_version != 2) {
 655#if DEBUG
 656			printk(OSST_DEB_MSG "%s:D: Skipping frame, partition num %d\n",
 657					    name, par->partition_num);
 658#endif
 659			goto err_out;
 660		}
 661	}
 662	if (par->par_desc_ver != OS_PARTITION_VERSION) {
 663#if DEBUG
 664		printk(OSST_DEB_MSG "%s:D: Skipping frame, partition version %d\n", name, par->par_desc_ver);
 665#endif
 666		goto err_out;
 667	}
 668	if (ntohs(par->wrt_pass_cntr) != STp->wrt_pass_cntr) {
 669#if DEBUG
 670		printk(OSST_DEB_MSG "%s:D: Skipping frame, wrt_pass_cntr %d (expected %d)\n", 
 671				    name, ntohs(par->wrt_pass_cntr), STp->wrt_pass_cntr);
 672#endif
 673		goto err_out;
 674	}
 675	if (aux->frame_type != OS_FRAME_TYPE_DATA &&
 676	    aux->frame_type != OS_FRAME_TYPE_EOD &&
 677	    aux->frame_type != OS_FRAME_TYPE_MARKER) {
 678		if (!quiet) {
 679#if DEBUG
 680			printk(OSST_DEB_MSG "%s:D: Skipping frame, frame type %x\n", name, aux->frame_type);
 681#endif
 682		}
 683		goto err_out;
 684	}
 685	if (aux->frame_type == OS_FRAME_TYPE_EOD &&
 686	    STp->first_frame_position < STp->eod_frame_ppos) {
 687		printk(KERN_INFO "%s:I: Skipping premature EOD frame %d\n", name,
 688				 STp->first_frame_position);
 689		goto err_out;
 690	}
 691        if (frame_seq_number != -1 && ntohl(aux->frame_seq_num) != frame_seq_number) {
 692		if (!quiet) {
 693#if DEBUG
 694			printk(OSST_DEB_MSG "%s:D: Skipping frame, sequence number %u (expected %d)\n", 
 695					    name, ntohl(aux->frame_seq_num), frame_seq_number);
 696#endif
 697		}
 698		goto err_out;
 699	}
 700	if (aux->frame_type == OS_FRAME_TYPE_MARKER) {
 701		STps->eof = ST_FM_HIT;
 702
 703		i = ntohl(aux->filemark_cnt);
 704		if (STp->header_cache != NULL && i < OS_FM_TAB_MAX && (i > STp->filemark_cnt ||
 705		    STp->first_frame_position - 1 != ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[i]))) {
 706#if DEBUG
 707			printk(OSST_DEB_MSG "%s:D: %s filemark %d at frame pos %d\n", name,
 708				  STp->header_cache->dat_fm_tab.fm_tab_ent[i] == 0?"Learned":"Corrected",
 709				  i, STp->first_frame_position - 1);
 710#endif
 711			STp->header_cache->dat_fm_tab.fm_tab_ent[i] = htonl(STp->first_frame_position - 1);
 712			if (i >= STp->filemark_cnt)
 713				 STp->filemark_cnt = i+1;
 714		}
 715	}
 716	if (aux->frame_type == OS_FRAME_TYPE_EOD) {
 717		STps->eof = ST_EOD_1;
 718		STp->frame_in_buffer = 1;
 719	}
 720	if (aux->frame_type == OS_FRAME_TYPE_DATA) {
 721                blk_cnt = ntohs(aux->dat.dat_list[0].blk_cnt);
 722		blk_sz  = ntohl(aux->dat.dat_list[0].blk_sz);
 723		STp->buffer->buffer_bytes = blk_cnt * blk_sz;
 724		STp->buffer->read_pointer = 0;
 725		STp->frame_in_buffer = 1;
 726
 727		/* See what block size was used to write file */
 728		if (STp->block_size != blk_sz && blk_sz > 0) {
 729			printk(KERN_INFO
 730	    	"%s:I: File was written with block size %d%c, currently %d%c, adjusted to match.\n",
 731       				name, blk_sz<1024?blk_sz:blk_sz/1024,blk_sz<1024?'b':'k',
 732				STp->block_size<1024?STp->block_size:STp->block_size/1024,
 733				STp->block_size<1024?'b':'k');
 734			STp->block_size            = blk_sz;
 735			STp->buffer->buffer_blocks = OS_DATA_SIZE / blk_sz;
 736		}
 737		STps->eof = ST_NOEOF;
 738	}
 739        STp->frame_seq_number = ntohl(aux->frame_seq_num);
 740	STp->logical_blk_num  = ntohl(aux->logical_blk_num);
 741	return 1;
 742
 743err_out:
 744	if (STp->read_error_frame == 0)
 745		STp->read_error_frame = STp->first_frame_position - 1;
 746	return 0;
 747}
 748
 749/*
 750 * Wait for the unit to become Ready
 751 */
 752static int osst_wait_ready(struct osst_tape * STp, struct osst_request ** aSRpnt,
 753				 unsigned timeout, int initial_delay)
 754{
 755	unsigned char		cmd[MAX_COMMAND_SIZE];
 756	struct osst_request   * SRpnt;
 757	unsigned long		startwait = jiffies;
 758#if DEBUG
 759	int			dbg  = debugging;
 760	char    	      * name = tape_name(STp);
 761
 762	printk(OSST_DEB_MSG "%s:D: Reached onstream wait ready\n", name);
 763#endif
 764
 765	if (initial_delay > 0)
 766		msleep(jiffies_to_msecs(initial_delay));
 767
 768	memset(cmd, 0, MAX_COMMAND_SIZE);
 769	cmd[0] = TEST_UNIT_READY;
 770
 771	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 772	*aSRpnt = SRpnt;
 773	if (!SRpnt) return (-EBUSY);
 774
 775	while ( STp->buffer->syscall_result && time_before(jiffies, startwait + timeout*HZ) &&
 776	       (( SRpnt->sense[2]  == 2 && SRpnt->sense[12] == 4    &&
 777		 (SRpnt->sense[13] == 1 || SRpnt->sense[13] == 8)    ) ||
 778		( SRpnt->sense[2]  == 6 && SRpnt->sense[12] == 0x28 &&
 779		  SRpnt->sense[13] == 0                                        )  )) {
 780#if DEBUG
 781	    if (debugging) {
 782		printk(OSST_DEB_MSG "%s:D: Sleeping in onstream wait ready\n", name);
 783		printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
 784		debugging = 0;
 785	    }
 786#endif
 787	    msleep(100);
 788
 789	    memset(cmd, 0, MAX_COMMAND_SIZE);
 790	    cmd[0] = TEST_UNIT_READY;
 791
 792	    SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 793	}
 794	*aSRpnt = SRpnt;
 795#if DEBUG
 796	debugging = dbg;
 797#endif
 798	if ( STp->buffer->syscall_result &&
 799	     osst_write_error_recovery(STp, aSRpnt, 0) ) {
 800#if DEBUG
 801	    printk(OSST_DEB_MSG "%s:D: Abnormal exit from onstream wait ready\n", name);
 802	    printk(OSST_DEB_MSG "%s:D: Result = %d, Sense: 0=%02x, 2=%02x, 12=%02x, 13=%02x\n", name,
 803			STp->buffer->syscall_result, SRpnt->sense[0], SRpnt->sense[2],
 804			SRpnt->sense[12], SRpnt->sense[13]);
 805#endif
 806	    return (-EIO);
 807	}
 808#if DEBUG
 809	printk(OSST_DEB_MSG "%s:D: Normal exit from onstream wait ready\n", name);
 810#endif
 811	return 0;
 812}
 813
 814/*
 815 * Wait for a tape to be inserted in the unit
 816 */
 817static int osst_wait_for_medium(struct osst_tape * STp, struct osst_request ** aSRpnt, unsigned timeout)
 818{
 819	unsigned char		cmd[MAX_COMMAND_SIZE];
 820	struct osst_request   * SRpnt;
 821	unsigned long		startwait = jiffies;
 822#if DEBUG
 823	int			dbg = debugging;
 824	char    	      * name = tape_name(STp);
 825
 826	printk(OSST_DEB_MSG "%s:D: Reached onstream wait for medium\n", name);
 827#endif
 828
 829	memset(cmd, 0, MAX_COMMAND_SIZE);
 830	cmd[0] = TEST_UNIT_READY;
 831
 832	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 833	*aSRpnt = SRpnt;
 834	if (!SRpnt) return (-EBUSY);
 835
 836	while ( STp->buffer->syscall_result && time_before(jiffies, startwait + timeout*HZ) &&
 837		SRpnt->sense[2] == 2 && SRpnt->sense[12] == 0x3a && SRpnt->sense[13] == 0  ) {
 838#if DEBUG
 839	    if (debugging) {
 840		printk(OSST_DEB_MSG "%s:D: Sleeping in onstream wait medium\n", name);
 841		printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
 842		debugging = 0;
 843	    }
 844#endif
 845	    msleep(100);
 846
 847	    memset(cmd, 0, MAX_COMMAND_SIZE);
 848	    cmd[0] = TEST_UNIT_READY;
 849
 850	    SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 851	}
 852	*aSRpnt = SRpnt;
 853#if DEBUG
 854	debugging = dbg;
 855#endif
 856	if ( STp->buffer->syscall_result     && SRpnt->sense[2]  != 2 &&
 857	     SRpnt->sense[12] != 4 && SRpnt->sense[13] == 1) {
 858#if DEBUG
 859	    printk(OSST_DEB_MSG "%s:D: Abnormal exit from onstream wait medium\n", name);
 860	    printk(OSST_DEB_MSG "%s:D: Result = %d, Sense: 0=%02x, 2=%02x, 12=%02x, 13=%02x\n", name,
 861			STp->buffer->syscall_result, SRpnt->sense[0], SRpnt->sense[2],
 862			SRpnt->sense[12], SRpnt->sense[13]);
 863#endif
 864	    return 0;
 865	}
 866#if DEBUG
 867	printk(OSST_DEB_MSG "%s:D: Normal exit from onstream wait medium\n", name);
 868#endif
 869	return 1;
 870}
 871
 872static int osst_position_tape_and_confirm(struct osst_tape * STp, struct osst_request ** aSRpnt, int frame)
 873{
 874	int	retval;
 875
 876	osst_wait_ready(STp, aSRpnt, 15 * 60, 0);			/* TODO - can this catch a write error? */
 877	retval = osst_set_frame_position(STp, aSRpnt, frame, 0);
 878	if (retval) return (retval);
 879	osst_wait_ready(STp, aSRpnt, 15 * 60, OSST_WAIT_POSITION_COMPLETE);
 880	return (osst_get_frame_position(STp, aSRpnt));
 881}
 882
 883/*
 884 * Wait for write(s) to complete
 885 */
 886static int osst_flush_drive_buffer(struct osst_tape * STp, struct osst_request ** aSRpnt)
 887{
 888	unsigned char		cmd[MAX_COMMAND_SIZE];
 889	struct osst_request   * SRpnt;
 890	int			result = 0;
 891	int			delay  = OSST_WAIT_WRITE_COMPLETE;
 892#if DEBUG
 893	char		      * name = tape_name(STp);
 894
 895	printk(OSST_DEB_MSG "%s:D: Reached onstream flush drive buffer (write filemark)\n", name);
 896#endif
 897
 898	memset(cmd, 0, MAX_COMMAND_SIZE);
 899	cmd[0] = WRITE_FILEMARKS;
 900	cmd[1] = 1;
 901
 902	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
 903	*aSRpnt = SRpnt;
 904	if (!SRpnt) return (-EBUSY);
 905	if (STp->buffer->syscall_result) {
 906		if ((SRpnt->sense[2] & 0x0f) == 2 && SRpnt->sense[12] == 4) {
 907			if (SRpnt->sense[13] == 8) {
 908				delay = OSST_WAIT_LONG_WRITE_COMPLETE;
 909			}
 910		} else
 911			result = osst_write_error_recovery(STp, aSRpnt, 0);
 912	}
 913	result |= osst_wait_ready(STp, aSRpnt, 5 * 60, delay);
 914	STp->ps[STp->partition].rw = OS_WRITING_COMPLETE;
 915
 916	return (result);
 917}
 918
 919#define OSST_POLL_PER_SEC 10
 920static int osst_wait_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int curr, int minlast, int to)
 921{
 922	unsigned long	startwait = jiffies;
 923	char	      * name      = tape_name(STp);
 924#if DEBUG
 925	char	   notyetprinted  = 1;
 926#endif
 927	if (minlast >= 0 && STp->ps[STp->partition].rw != ST_READING)
 928		printk(KERN_ERR "%s:A: Waiting for frame without having initialized read!\n", name);
 929
 930	while (time_before (jiffies, startwait + to*HZ))
 931	{ 
 932		int result;
 933		result = osst_get_frame_position(STp, aSRpnt);
 934		if (result == -EIO)
 935			if ((result = osst_write_error_recovery(STp, aSRpnt, 0)) == 0)
 936				return 0;	/* successful recovery leaves drive ready for frame */
 937		if (result < 0) break;
 938		if (STp->first_frame_position == curr &&
 939		    ((minlast < 0 &&
 940		      (signed)STp->last_frame_position > (signed)curr + minlast) ||
 941		     (minlast >= 0 && STp->cur_frames > minlast)
 942		    ) && result >= 0)
 943		{
 944#if DEBUG			
 945			if (debugging || time_after_eq(jiffies, startwait + 2*HZ/OSST_POLL_PER_SEC))
 946				printk (OSST_DEB_MSG
 947					"%s:D: Succ wait f fr %i (>%i): %i-%i %i (%i): %3li.%li s\n",
 948					name, curr, curr+minlast, STp->first_frame_position,
 949					STp->last_frame_position, STp->cur_frames,
 950					result, (jiffies-startwait)/HZ, 
 951					(((jiffies-startwait)%HZ)*10)/HZ);
 952#endif
 953			return 0;
 954		}
 955#if DEBUG
 956		if (time_after_eq(jiffies, startwait + 2*HZ/OSST_POLL_PER_SEC) && notyetprinted)
 957		{
 958			printk (OSST_DEB_MSG "%s:D: Wait for frame %i (>%i): %i-%i %i (%i)\n",
 959				name, curr, curr+minlast, STp->first_frame_position,
 960				STp->last_frame_position, STp->cur_frames, result);
 961			notyetprinted--;
 962		}
 963#endif
 964		msleep(1000 / OSST_POLL_PER_SEC);
 965	}
 966#if DEBUG
 967	printk (OSST_DEB_MSG "%s:D: Fail wait f fr %i (>%i): %i-%i %i: %3li.%li s\n",
 968		name, curr, curr+minlast, STp->first_frame_position,
 969		STp->last_frame_position, STp->cur_frames,
 970		(jiffies-startwait)/HZ, (((jiffies-startwait)%HZ)*10)/HZ);
 971#endif	
 972	return -EBUSY;
 973}
 974
 975static int osst_recover_wait_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int writing)
 976{
 977	struct osst_request   * SRpnt;
 978	unsigned char		cmd[MAX_COMMAND_SIZE];
 979	unsigned long   	startwait = jiffies;
 980	int			retval    = 1;
 981        char		      * name      = tape_name(STp);
 982                                                                                                                                
 983	if (writing) {
 984		char	mybuf[24];
 985		char  * olddata = STp->buffer->b_data;
 986		int	oldsize = STp->buffer->buffer_size;
 987
 988		/* write zero fm then read pos - if shows write error, try to recover - if no progress, wait */
 989
 990		memset(cmd, 0, MAX_COMMAND_SIZE);
 991		cmd[0] = WRITE_FILEMARKS;
 992		cmd[1] = 1;
 993		SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout,
 994								MAX_RETRIES, 1);
 995
 996		while (retval && time_before (jiffies, startwait + 5*60*HZ)) {
 997
 998			if (STp->buffer->syscall_result && (SRpnt->sense[2] & 0x0f) != 2) {
 999
1000				/* some failure - not just not-ready */
1001				retval = osst_write_error_recovery(STp, aSRpnt, 0);
1002				break;
1003			}
1004			schedule_timeout_interruptible(HZ / OSST_POLL_PER_SEC);
1005
1006			STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
1007			memset(cmd, 0, MAX_COMMAND_SIZE);
1008			cmd[0] = READ_POSITION;
1009
1010			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 20, DMA_FROM_DEVICE, STp->timeout,
1011										MAX_RETRIES, 1);
1012
1013			retval = ( STp->buffer->syscall_result || (STp->buffer)->b_data[15] > 25 );
1014			STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
1015		}
1016		if (retval)
1017			printk(KERN_ERR "%s:E: Device did not succeed to write buffered data\n", name);
1018	} else
1019		/* TODO - figure out which error conditions can be handled */
1020		if (STp->buffer->syscall_result)
1021			printk(KERN_WARNING
1022				"%s:W: Recover_wait_frame(read) cannot handle %02x:%02x:%02x\n", name,
1023					(*aSRpnt)->sense[ 2] & 0x0f,
1024					(*aSRpnt)->sense[12],
1025					(*aSRpnt)->sense[13]);
1026
1027	return retval;
1028}
1029
1030/*
1031 * Read the next OnStream tape frame at the current location
1032 */
1033static int osst_read_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int timeout)
1034{
1035	unsigned char		cmd[MAX_COMMAND_SIZE];
1036	struct osst_request   * SRpnt;
1037	int			retval = 0;
1038#if DEBUG
1039	os_aux_t	      * aux    = STp->buffer->aux;
1040	char		      * name   = tape_name(STp);
1041#endif
1042
1043	if (STp->poll)
1044		if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, 0, timeout))
1045			retval = osst_recover_wait_frame(STp, aSRpnt, 0);
1046
1047	memset(cmd, 0, MAX_COMMAND_SIZE);
1048	cmd[0] = READ_6;
1049	cmd[1] = 1;
1050	cmd[4] = 1;
1051
1052#if DEBUG
1053	if (debugging)
1054		printk(OSST_DEB_MSG "%s:D: Reading frame from OnStream tape\n", name);
1055#endif
1056	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_FROM_DEVICE,
1057				      STp->timeout, MAX_RETRIES, 1);
1058	*aSRpnt = SRpnt;
1059	if (!SRpnt)
1060		return (-EBUSY);
1061
1062	if ((STp->buffer)->syscall_result) {
1063	    retval = 1;
1064	    if (STp->read_error_frame == 0) {
1065		STp->read_error_frame = STp->first_frame_position;
1066#if DEBUG
1067		printk(OSST_DEB_MSG "%s:D: Recording read error at %d\n", name, STp->read_error_frame);
1068#endif
1069	    }
1070#if DEBUG
1071	    if (debugging)
1072		printk(OSST_DEB_MSG "%s:D: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1073		   name,
1074		   SRpnt->sense[0], SRpnt->sense[1],
1075		   SRpnt->sense[2], SRpnt->sense[3],
1076		   SRpnt->sense[4], SRpnt->sense[5],
1077		   SRpnt->sense[6], SRpnt->sense[7]);
1078#endif
1079	}
1080	else
1081	    STp->first_frame_position++;
1082#if DEBUG
1083	if (debugging) {
1084	   char sig[8]; int i;
1085	   for (i=0;i<4;i++)
1086		   sig[i] = aux->application_sig[i]<32?'^':aux->application_sig[i];
1087	   sig[4] = '\0';
1088	   printk(OSST_DEB_MSG 
1089		"%s:D: AUX: %s UpdFrCt#%d Wpass#%d %s FrSeq#%d LogBlk#%d Qty=%d Sz=%d\n", name, sig,
1090			ntohl(aux->update_frame_cntr), ntohs(aux->partition.wrt_pass_cntr),
1091			aux->frame_type==1?"EOD":aux->frame_type==2?"MARK":
1092			aux->frame_type==8?"HEADR":aux->frame_type==0x80?"DATA":"FILL", 
1093			ntohl(aux->frame_seq_num), ntohl(aux->logical_blk_num),
1094			ntohs(aux->dat.dat_list[0].blk_cnt), ntohl(aux->dat.dat_list[0].blk_sz) );
1095	   if (aux->frame_type==2)
1096		printk(OSST_DEB_MSG "%s:D: mark_cnt=%d, last_mark_ppos=%d, last_mark_lbn=%d\n", name,
1097			ntohl(aux->filemark_cnt), ntohl(aux->last_mark_ppos), ntohl(aux->last_mark_lbn));
1098	   printk(OSST_DEB_MSG "%s:D: Exit read frame from OnStream tape with code %d\n", name, retval);
1099	}
1100#endif
1101	return (retval);
1102}
1103
1104static int osst_initiate_read(struct osst_tape * STp, struct osst_request ** aSRpnt)
1105{
1106	struct st_partstat    * STps   = &(STp->ps[STp->partition]);
1107	struct osst_request   * SRpnt  ;
1108	unsigned char		cmd[MAX_COMMAND_SIZE];
1109	int			retval = 0;
1110	char		      * name   = tape_name(STp);
1111
1112	if (STps->rw != ST_READING) {         /* Initialize read operation */
1113		if (STps->rw == ST_WRITING || STp->dirty) {
1114			STp->write_type = OS_WRITE_DATA;
1115                        osst_flush_write_buffer(STp, aSRpnt);
1116			osst_flush_drive_buffer(STp, aSRpnt);
1117		}
1118		STps->rw = ST_READING;
1119		STp->frame_in_buffer = 0;
1120
1121		/*
1122		 *      Issue a read 0 command to get the OnStream drive
1123                 *      read frames into its buffer.
1124		 */
1125		memset(cmd, 0, MAX_COMMAND_SIZE);
1126		cmd[0] = READ_6;
1127		cmd[1] = 1;
1128
1129#if DEBUG
1130		printk(OSST_DEB_MSG "%s:D: Start Read Ahead on OnStream tape\n", name);
1131#endif
1132		SRpnt   = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
1133		*aSRpnt = SRpnt;
1134		if ((retval = STp->buffer->syscall_result))
1135			printk(KERN_WARNING "%s:W: Error starting read ahead\n", name);
1136	}
1137
1138	return retval;
1139}
1140
1141static int osst_get_logical_frame(struct osst_tape * STp, struct osst_request ** aSRpnt,
1142						int frame_seq_number, int quiet)
1143{
1144	struct st_partstat * STps  = &(STp->ps[STp->partition]);
1145	char		   * name  = tape_name(STp);
1146	int		     cnt   = 0,
1147			     bad   = 0,
1148			     past  = 0,
1149			     x,
1150			     position;
1151
1152	/*
1153	 * If we want just any frame (-1) and there is a frame in the buffer, return it
1154	 */
1155	if (frame_seq_number == -1 && STp->frame_in_buffer) {
1156#if DEBUG
1157		printk(OSST_DEB_MSG "%s:D: Frame %d still in buffer\n", name, STp->frame_seq_number);
1158#endif
1159		return (STps->eof);
1160	}
1161	/*
1162         * Search and wait for the next logical tape frame
1163	 */
1164	while (1) {
1165		if (cnt++ > 400) {
1166                        printk(KERN_ERR "%s:E: Couldn't find logical frame %d, aborting\n",
1167					    name, frame_seq_number);
1168			if (STp->read_error_frame) {
1169				osst_set_frame_position(STp, aSRpnt, STp->read_error_frame, 0);
1170#if DEBUG
1171                        	printk(OSST_DEB_MSG "%s:D: Repositioning tape to bad frame %d\n",
1172						    name, STp->read_error_frame);
1173#endif
1174				STp->read_error_frame = 0;
1175				STp->abort_count++;
1176			}
1177			return (-EIO);
1178		}
1179#if DEBUG
1180		if (debugging)
1181			printk(OSST_DEB_MSG "%s:D: Looking for frame %d, attempt %d\n",
1182					  name, frame_seq_number, cnt);
1183#endif
1184		if ( osst_initiate_read(STp, aSRpnt)
1185                || ( (!STp->frame_in_buffer) && osst_read_frame(STp, aSRpnt, 30) ) ) {
1186			if (STp->raw)
1187				return (-EIO);
1188			position = osst_get_frame_position(STp, aSRpnt);
1189			if (position >= 0xbae && position < 0xbb8)
1190				position = 0xbb8;
1191			else if (position > STp->eod_frame_ppos || ++bad == 10) {
1192				position = STp->read_error_frame - 1;
1193				bad = 0;
1194			}
1195			else {
1196				position += 29;
1197				cnt      += 19;
1198			}
1199#if DEBUG
1200			printk(OSST_DEB_MSG "%s:D: Bad frame detected, positioning tape to block %d\n",
1201					 name, position);
1202#endif
1203			osst_set_frame_position(STp, aSRpnt, position, 0);
1204			continue;
1205		}
1206		if (osst_verify_frame(STp, frame_seq_number, quiet))
1207			break;
1208		if (osst_verify_frame(STp, -1, quiet)) {
1209			x = ntohl(STp->buffer->aux->frame_seq_num);
1210			if (STp->fast_open) {
1211				printk(KERN_WARNING
1212				       "%s:W: Found logical frame %d instead of %d after fast open\n",
1213				       name, x, frame_seq_number);
1214				STp->header_ok = 0;
1215				STp->read_error_frame = 0;
1216				return (-EIO);
1217			}
1218			if (x > frame_seq_number) {
1219				if (++past > 3) {
1220					/* positioning backwards did not bring us to the desired frame */
1221					position = STp->read_error_frame - 1;
1222				}
1223				else {
1224			        	position = osst_get_frame_position(STp, aSRpnt)
1225					         + frame_seq_number - x - 1;
1226
1227					if (STp->first_frame_position >= 3000 && position < 3000)
1228						position -= 10;
1229				}
1230#if DEBUG
1231                                printk(OSST_DEB_MSG
1232				       "%s:D: Found logical frame %d while looking for %d: back up %d\n",
1233						name, x, frame_seq_number,
1234					       	STp->first_frame_position - position);
1235#endif
1236                        	osst_set_frame_position(STp, aSRpnt, position, 0);
1237				cnt += 10;
1238			}
1239			else
1240				past = 0;
1241		}
1242		if (osst_get_frame_position(STp, aSRpnt) == 0xbaf) {
1243#if DEBUG
1244			printk(OSST_DEB_MSG "%s:D: Skipping config partition\n", name);
1245#endif
1246			osst_set_frame_position(STp, aSRpnt, 0xbb8, 0);
1247			cnt--;
1248		}
1249		STp->frame_in_buffer = 0;
1250	}
1251	if (cnt > 1) {
1252		STp->recover_count++;
1253		STp->recover_erreg++;
1254		printk(KERN_WARNING "%s:I: Don't worry, Read error at position %d recovered\n", 
1255					name, STp->read_error_frame);
1256 	}
1257	STp->read_count++;
1258
1259#if DEBUG
1260	if (debugging || STps->eof)
1261		printk(OSST_DEB_MSG
1262			"%s:D: Exit get logical frame (%d=>%d) from OnStream tape with code %d\n",
1263			name, frame_seq_number, STp->frame_seq_number, STps->eof);
1264#endif
1265	STp->fast_open = 0;
1266	STp->read_error_frame = 0;
1267	return (STps->eof);
1268}
1269
1270static int osst_seek_logical_blk(struct osst_tape * STp, struct osst_request ** aSRpnt, int logical_blk_num)
1271{
1272        struct st_partstat * STps = &(STp->ps[STp->partition]);
1273	char		   * name = tape_name(STp);
1274	int	retries    = 0;
1275	int	frame_seq_estimate, ppos_estimate, move;
1276	
1277	if (logical_blk_num < 0) logical_blk_num = 0;
1278#if DEBUG
1279	printk(OSST_DEB_MSG "%s:D: Seeking logical block %d (now at %d, size %d%c)\n",
1280				name, logical_blk_num, STp->logical_blk_num, 
1281				STp->block_size<1024?STp->block_size:STp->block_size/1024,
1282				STp->block_size<1024?'b':'k');
1283#endif
1284	/* Do we know where we are? */
1285	if (STps->drv_block >= 0) {
1286		move                = logical_blk_num - STp->logical_blk_num;
1287		if (move < 0) move -= (OS_DATA_SIZE / STp->block_size) - 1;
1288		move               /= (OS_DATA_SIZE / STp->block_size);
1289		frame_seq_estimate  = STp->frame_seq_number + move;
1290	} else
1291		frame_seq_estimate  = logical_blk_num * STp->block_size / OS_DATA_SIZE;
1292
1293	if (frame_seq_estimate < 2980) ppos_estimate = frame_seq_estimate + 10;
1294	else			       ppos_estimate = frame_seq_estimate + 20;
1295	while (++retries < 10) {
1296	   if (ppos_estimate > STp->eod_frame_ppos-2) {
1297	       frame_seq_estimate += STp->eod_frame_ppos - 2 - ppos_estimate;
1298	       ppos_estimate       = STp->eod_frame_ppos - 2;
1299	   }
1300	   if (frame_seq_estimate < 0) {
1301	       frame_seq_estimate = 0;
1302	       ppos_estimate      = 10;
1303	   }
1304	   osst_set_frame_position(STp, aSRpnt, ppos_estimate, 0);
1305	   if (osst_get_logical_frame(STp, aSRpnt, frame_seq_estimate, 1) >= 0) {
1306	      /* we've located the estimated frame, now does it have our block? */
1307	      if (logical_blk_num <  STp->logical_blk_num ||
1308	          logical_blk_num >= STp->logical_blk_num + ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt)) {
1309		 if (STps->eof == ST_FM_HIT)
1310		    move = logical_blk_num < STp->logical_blk_num? -2 : 1;
1311		 else {
1312		    move                = logical_blk_num - STp->logical_blk_num;
1313		    if (move < 0) move -= (OS_DATA_SIZE / STp->block_size) - 1;
1314		    move               /= (OS_DATA_SIZE / STp->block_size);
1315		 }
1316		 if (!move) move = logical_blk_num > STp->logical_blk_num ? 1 : -1;
1317#if DEBUG
1318		 printk(OSST_DEB_MSG
1319			"%s:D: Seek retry %d at ppos %d fsq %d (est %d) lbn %d (need %d) move %d\n",
1320				name, retries, ppos_estimate, STp->frame_seq_number, frame_seq_estimate, 
1321				STp->logical_blk_num, logical_blk_num, move);
1322#endif
1323		 frame_seq_estimate += move;
1324		 ppos_estimate      += move;
1325		 continue;
1326	      } else {
1327		 STp->buffer->read_pointer  = (logical_blk_num - STp->logical_blk_num) * STp->block_size;
1328		 STp->buffer->buffer_bytes -= STp->buffer->read_pointer;
1329		 STp->logical_blk_num       =  logical_blk_num;
1330#if DEBUG
1331		 printk(OSST_DEB_MSG 
1332			"%s:D: Seek success at ppos %d fsq %d in_buf %d, bytes %d, ptr %d*%d\n",
1333				name, ppos_estimate, STp->frame_seq_number, STp->frame_in_buffer, 
1334				STp->buffer->buffer_bytes, STp->buffer->read_pointer / STp->block_size, 
1335				STp->block_size);
1336#endif
1337		 STps->drv_file = ntohl(STp->buffer->aux->filemark_cnt);
1338		 if (STps->eof == ST_FM_HIT) {
1339		     STps->drv_file++;
1340		     STps->drv_block = 0;
1341		 } else {
1342		     STps->drv_block = ntohl(STp->buffer->aux->last_mark_lbn)?
1343					  STp->logical_blk_num -
1344					     (STps->drv_file ? ntohl(STp->buffer->aux->last_mark_lbn) + 1 : 0):
1345					-1;
1346		 }
1347		 STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_NOEOF;
1348		 return 0;
1349	      }
1350	   }
1351	   if (osst_get_logical_frame(STp, aSRpnt, -1, 1) < 0)
1352	      goto error;
1353	   /* we are not yet at the estimated frame, adjust our estimate of its physical position */
1354#if DEBUG
1355	   printk(OSST_DEB_MSG "%s:D: Seek retry %d at ppos %d fsq %d (est %d) lbn %d (need %d)\n", 
1356			   name, retries, ppos_estimate, STp->frame_seq_number, frame_seq_estimate, 
1357			   STp->logical_blk_num, logical_blk_num);
1358#endif
1359	   if (frame_seq_estimate != STp->frame_seq_number)
1360	      ppos_estimate += frame_seq_estimate - STp->frame_seq_number;
1361	   else
1362	      break;
1363	}
1364error:
1365	printk(KERN_ERR "%s:E: Couldn't seek to logical block %d (at %d), %d retries\n", 
1366			    name, logical_blk_num, STp->logical_blk_num, retries);
1367	return (-EIO);
1368}
1369
1370/* The values below are based on the OnStream frame payload size of 32K == 2**15,
1371 * that is, OSST_FRAME_SHIFT + OSST_SECTOR_SHIFT must be 15. With a minimum block
1372 * size of 512 bytes, we need to be able to resolve 32K/512 == 64 == 2**6 positions
1373 * inside each frame. Finally, OSST_SECTOR_MASK == 2**OSST_FRAME_SHIFT - 1.
1374 */
1375#define OSST_FRAME_SHIFT  6
1376#define OSST_SECTOR_SHIFT 9
1377#define OSST_SECTOR_MASK  0x03F
1378
1379static int osst_get_sector(struct osst_tape * STp, struct osst_request ** aSRpnt)
1380{
1381	int	sector;
1382#if DEBUG
1383	char  * name = tape_name(STp);
1384	
1385	printk(OSST_DEB_MSG 
1386		"%s:D: Positioned at ppos %d, frame %d, lbn %d, file %d, blk %d, %cptr %d, eof %d\n",
1387		name, STp->first_frame_position, STp->frame_seq_number, STp->logical_blk_num,
1388		STp->ps[STp->partition].drv_file, STp->ps[STp->partition].drv_block, 
1389		STp->ps[STp->partition].rw == ST_WRITING?'w':'r',
1390		STp->ps[STp->partition].rw == ST_WRITING?STp->buffer->buffer_bytes:
1391		STp->buffer->read_pointer, STp->ps[STp->partition].eof);
1392#endif
1393	/* do we know where we are inside a file? */
1394	if (STp->ps[STp->partition].drv_block >= 0) {
1395		sector = (STp->frame_in_buffer ? STp->first_frame_position-1 :
1396				STp->first_frame_position) << OSST_FRAME_SHIFT;
1397		if (STp->ps[STp->partition].rw == ST_WRITING)
1398		       	sector |= (STp->buffer->buffer_bytes >> OSST_SECTOR_SHIFT) & OSST_SECTOR_MASK;
1399		else
1400	       		sector |= (STp->buffer->read_pointer >> OSST_SECTOR_SHIFT) & OSST_SECTOR_MASK;
1401	} else {
1402		sector = osst_get_frame_position(STp, aSRpnt);
1403		if (sector > 0)
1404			sector <<= OSST_FRAME_SHIFT;
1405	}
1406	return sector;
1407}
1408
1409static int osst_seek_sector(struct osst_tape * STp, struct osst_request ** aSRpnt, int sector)
1410{
1411        struct st_partstat * STps   = &(STp->ps[STp->partition]);
1412	int		     frame  = sector >> OSST_FRAME_SHIFT,
1413			     offset = (sector & OSST_SECTOR_MASK) << OSST_SECTOR_SHIFT, 
1414			     r;
1415#if DEBUG
1416	char          * name = tape_name(STp);
1417
1418	printk(OSST_DEB_MSG "%s:D: Seeking sector %d in frame %d at offset %d\n",
1419				name, sector, frame, offset);
1420#endif
1421	if (frame < 0 || frame >= STp->capacity) return (-ENXIO);
1422
1423	if (frame <= STp->first_data_ppos) {
1424		STp->frame_seq_number = STp->logical_blk_num = STps->drv_file = STps->drv_block = 0;
1425		return (osst_set_frame_position(STp, aSRpnt, frame, 0));
1426	}
1427	r = osst_set_frame_position(STp, aSRpnt, offset?frame:frame-1, 0);
1428	if (r < 0) return r;
1429
1430	r = osst_get_logical_frame(STp, aSRpnt, -1, 1);
1431	if (r < 0) return r;
1432
1433	if (osst_get_frame_position(STp, aSRpnt) != (offset?frame+1:frame)) return (-EIO);
1434
1435	if (offset) {
1436		STp->logical_blk_num      += offset / STp->block_size;
1437		STp->buffer->read_pointer  = offset;
1438		STp->buffer->buffer_bytes -= offset;
1439	} else {
1440		STp->frame_seq_number++;
1441		STp->frame_in_buffer       = 0;
1442		STp->logical_blk_num      += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1443		STp->buffer->buffer_bytes  = STp->buffer->read_pointer = 0;
1444	}
1445	STps->drv_file = ntohl(STp->buffer->aux->filemark_cnt);
1446	if (STps->eof == ST_FM_HIT) {
1447		STps->drv_file++;
1448		STps->drv_block = 0;
1449	} else {
1450		STps->drv_block = ntohl(STp->buffer->aux->last_mark_lbn)?
1451				    STp->logical_blk_num -
1452					(STps->drv_file ? ntohl(STp->buffer->aux->last_mark_lbn) + 1 : 0):
1453				  -1;
1454	}
1455	STps->eof       = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_NOEOF;
1456#if DEBUG
1457	printk(OSST_DEB_MSG 
1458		"%s:D: Now positioned at ppos %d, frame %d, lbn %d, file %d, blk %d, rptr %d, eof %d\n",
1459		name, STp->first_frame_position, STp->frame_seq_number, STp->logical_blk_num,
1460		STps->drv_file, STps->drv_block, STp->buffer->read_pointer, STps->eof);
1461#endif
1462	return 0;
1463}
1464
1465/*
1466 * Read back the drive's internal buffer contents, as a part
1467 * of the write error recovery mechanism for old OnStream
1468 * firmware revisions.
1469 * Precondition for this function to work: all frames in the
1470 * drive's buffer must be of one type (DATA, MARK or EOD)!
1471 */
1472static int osst_read_back_buffer_and_rewrite(struct osst_tape * STp, struct osst_request ** aSRpnt,
1473						unsigned int frame, unsigned int skip, int pending)
1474{
1475	struct osst_request   * SRpnt = * aSRpnt;
1476	unsigned char	      * buffer, * p;
1477	unsigned char		cmd[MAX_COMMAND_SIZE];
1478	int			flag, new_frame, i;
1479	int			nframes          = STp->cur_frames;
1480	int			blks_per_frame   = ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1481	int			frame_seq_number = ntohl(STp->buffer->aux->frame_seq_num)
1482						- (nframes + pending - 1);
1483	int			logical_blk_num  = ntohl(STp->buffer->aux->logical_blk_num) 
1484						- (nframes + pending - 1) * blks_per_frame;
1485	char		      * name             = tape_name(STp);
1486	unsigned long		startwait        = jiffies;
1487#if DEBUG
1488	int			dbg              = debugging;
1489#endif
1490
1491	if ((buffer = vmalloc((nframes + 1) * OS_DATA_SIZE)) == NULL)
1492		return (-EIO);
1493
1494	printk(KERN_INFO "%s:I: Reading back %d frames from drive buffer%s\n",
1495			 name, nframes, pending?" and one that was pending":"");
1496
1497	osst_copy_from_buffer(STp->buffer, (p = &buffer[nframes * OS_DATA_SIZE]));
1498#if DEBUG
1499	if (pending && debugging)
1500		printk(OSST_DEB_MSG "%s:D: Pending frame %d (lblk %d), data %02x %02x %02x %02x\n",
1501				name, frame_seq_number + nframes,
1502			       	logical_blk_num + nframes * blks_per_frame,
1503			       	p[0], p[1], p[2], p[3]);
1504#endif
1505	for (i = 0, p = buffer; i < nframes; i++, p += OS_DATA_SIZE) {
1506
1507		memset(cmd, 0, MAX_COMMAND_SIZE);
1508		cmd[0] = 0x3C;		/* Buffer Read           */
1509		cmd[1] = 6;		/* Retrieve Faulty Block */
1510		cmd[7] = 32768 >> 8;
1511		cmd[8] = 32768 & 0xff;
1512
1513		SRpnt = osst_do_scsi(SRpnt, STp, cmd, OS_FRAME_SIZE, DMA_FROM_DEVICE,
1514					    STp->timeout, MAX_RETRIES, 1);
1515	
1516		if ((STp->buffer)->syscall_result || !SRpnt) {
1517			printk(KERN_ERR "%s:E: Failed to read frame back from OnStream buffer\n", name);
1518			vfree(buffer);
1519			*aSRpnt = SRpnt;
1520			return (-EIO);
1521		}
1522		osst_copy_from_buffer(STp->buffer, p);
1523#if DEBUG
1524		if (debugging)
1525			printk(OSST_DEB_MSG "%s:D: Read back logical frame %d, data %02x %02x %02x %02x\n",
1526					  name, frame_seq_number + i, p[0], p[1], p[2], p[3]);
1527#endif
1528	}
1529	*aSRpnt = SRpnt;
1530	osst_get_frame_position(STp, aSRpnt);
1531
1532#if DEBUG
1533	printk(OSST_DEB_MSG "%s:D: Frames left in buffer: %d\n", name, STp->cur_frames);
1534#endif
1535	/* Write synchronously so we can be sure we're OK again and don't have to recover recursively */
1536	/* In the header we don't actually re-write the frames that fail, just the ones after them */
1537
1538	for (flag=1, new_frame=frame, p=buffer, i=0; i < nframes + pending; ) {
1539
1540		if (flag) {
1541			if (STp->write_type == OS_WRITE_HEADER) {
1542				i += skip;
1543				p += skip * OS_DATA_SIZE;
1544			}
1545			else if (new_frame < 2990 && new_frame+skip+nframes+pending >= 2990)
1546				new_frame = 3000-i;
1547			else
1548				new_frame += skip;
1549#if DEBUG
1550			printk(OSST_DEB_MSG "%s:D: Position to frame %d, write fseq %d\n",
1551						name, new_frame+i, frame_seq_number+i);
1552#endif
1553			osst_set_frame_position(STp, aSRpnt, new_frame + i, 0);
1554			osst_wait_ready(STp, aSRpnt, 60, OSST_WAIT_POSITION_COMPLETE);
1555			osst_get_frame_position(STp, aSRpnt);
1556			SRpnt = * aSRpnt;
1557
1558			if (new_frame > frame + 1000) {
1559				printk(KERN_ERR "%s:E: Failed to find writable tape media\n", name);
1560				vfree(buffer);
1561				return (-EIO);
1562			}
1563			if ( i >= nframes + pending ) break;
1564			flag = 0;
1565		}
1566		osst_copy_to_buffer(STp->buffer, p);
1567		/*
1568		 * IMPORTANT: for error recovery to work, _never_ queue frames with mixed frame type!
1569		 */
1570		osst_init_aux(STp, STp->buffer->aux->frame_type, frame_seq_number+i,
1571			       	logical_blk_num + i*blks_per_frame,
1572			       	ntohl(STp->buffer->aux->dat.dat_list[0].blk_sz), blks_per_frame);
1573		memset(cmd, 0, MAX_COMMAND_SIZE);
1574		cmd[0] = WRITE_6;
1575		cmd[1] = 1;
1576		cmd[4] = 1;
1577
1578#if DEBUG
1579		if (debugging)
1580			printk(OSST_DEB_MSG
1581				"%s:D: About to write frame %d, seq %d, lbn %d, data %02x %02x %02x %02x\n",
1582				name, new_frame+i, frame_seq_number+i, logical_blk_num + i*blks_per_frame,
1583				p[0], p[1], p[2], p[3]);
1584#endif
1585		SRpnt = osst_do_scsi(SRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE,
1586					    STp->timeout, MAX_RETRIES, 1);
1587
1588		if (STp->buffer->syscall_result)
1589			flag = 1;
1590		else {
1591			p += OS_DATA_SIZE; i++;
1592
1593			/* if we just sent the last frame, wait till all successfully written */
1594			if ( i == nframes + pending ) {
1595#if DEBUG
1596				printk(OSST_DEB_MSG "%s:D: Check re-write successful\n", name);
1597#endif
1598				memset(cmd, 0, MAX_COMMAND_SIZE);
1599				cmd[0] = WRITE_FILEMARKS;
1600				cmd[1] = 1;
1601				SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
1602							    STp->timeout, MAX_RETRIES, 1);
1603#if DEBUG
1604				if (debugging) {
1605					printk(OSST_DEB_MSG "%s:D: Sleeping in re-write wait ready\n", name);
1606					printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
1607					debugging = 0;
1608				}
1609#endif
1610				flag = STp->buffer->syscall_result;
1611				while ( !flag && time_before(jiffies, startwait + 60*HZ) ) {
1612
1613					memset(cmd, 0, MAX_COMMAND_SIZE);
1614					cmd[0] = TEST_UNIT_READY;
1615
1616					SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout,
1617												MAX_RETRIES, 1);
1618
1619					if (SRpnt->sense[2] == 2 && SRpnt->sense[12] == 4 &&
1620					    (SRpnt->sense[13] == 1 || SRpnt->sense[13] == 8)) {
1621						/* in the process of becoming ready */
1622						msleep(100);
1623						continue;
1624					}
1625					if (STp->buffer->syscall_result)
1626						flag = 1;
1627					break;
1628				}
1629#if DEBUG
1630				debugging = dbg;
1631				printk(OSST_DEB_MSG "%s:D: Wait re-write finished\n", name);
1632#endif
1633			}
1634		}
1635		*aSRpnt = SRpnt;
1636		if (flag) {
1637			if ((SRpnt->sense[ 2] & 0x0f) == 13 &&
1638			     SRpnt->sense[12]         ==  0 &&
1639			     SRpnt->sense[13]         ==  2) {
1640				printk(KERN_ERR "%s:E: Volume overflow in write error recovery\n", name);
1641				vfree(buffer);
1642				return (-EIO);			/* hit end of tape = fail */
1643			}
1644			i = ((SRpnt->sense[3] << 24) |
1645			     (SRpnt->sense[4] << 16) |
1646			     (SRpnt->sense[5] <<  8) |
1647			      SRpnt->sense[6]        ) - new_frame;
1648			p = &buffer[i * OS_DATA_SIZE];
1649#if DEBUG
1650			printk(OSST_DEB_MSG "%s:D: Additional write error at %d\n", name, new_frame+i);
1651#endif
1652			osst_get_frame_position(STp, aSRpnt);
1653#if DEBUG
1654			printk(OSST_DEB_MSG "%s:D: reported frame positions: host = %d, tape = %d, buffer = %d\n",
1655					  name, STp->first_frame_position, STp->last_frame_position, STp->cur_frames);
1656#endif
1657		}
1658	}
1659	if (flag) {
1660		/* error recovery did not successfully complete */
1661		printk(KERN_ERR "%s:D: Write error recovery failed in %s\n", name,
1662				STp->write_type == OS_WRITE_HEADER?"header":"body");
1663	}
1664	if (!pending)
1665		osst_copy_to_buffer(STp->buffer, p);	/* so buffer content == at entry in all cases */
1666	vfree(buffer);
1667	return 0;
1668}
1669
1670static int osst_reposition_and_retry(struct osst_tape * STp, struct osst_request ** aSRpnt,
1671					unsigned int frame, unsigned int skip, int pending)
1672{
1673	unsigned char		cmd[MAX_COMMAND_SIZE];
1674	struct osst_request   * SRpnt;
1675	char		      * name      = tape_name(STp);
1676	int			expected  = 0;
1677	int			attempts  = 1000 / skip;
1678	int			flag      = 1;
1679	unsigned long		startwait = jiffies;
1680#if DEBUG
1681	int			dbg       = debugging;
1682#endif
1683
1684	while (attempts && time_before(jiffies, startwait + 60*HZ)) {
1685		if (flag) {
1686#if DEBUG
1687			debugging = dbg;
1688#endif
1689			if (frame < 2990 && frame+skip+STp->cur_frames+pending >= 2990)
1690				frame = 3000-skip;
1691			expected = frame+skip+STp->cur_frames+pending;
1692#if DEBUG
1693			printk(OSST_DEB_MSG "%s:D: Position to fppos %d, re-write from fseq %d\n",
1694					  name, frame+skip, STp->frame_seq_number-STp->cur_frames-pending);
1695#endif
1696			osst_set_frame_position(STp, aSRpnt, frame + skip, 1);
1697			flag = 0;
1698			attempts--;
1699			schedule_timeout_interruptible(msecs_to_jiffies(100));
1700		}
1701		if (osst_get_frame_position(STp, aSRpnt) < 0) {		/* additional write error */
1702#if DEBUG
1703			printk(OSST_DEB_MSG "%s:D: Addl error, host %d, tape %d, buffer %d\n",
1704					  name, STp->first_frame_position,
1705					  STp->last_frame_position, STp->cur_frames);
1706#endif
1707			frame = STp->last_frame_position;
1708			flag = 1;
1709			continue;
1710		}
1711		if (pending && STp->cur_frames < 50) {
1712
1713			memset(cmd, 0, MAX_COMMAND_SIZE);
1714			cmd[0] = WRITE_6;
1715			cmd[1] = 1;
1716			cmd[4] = 1;
1717#if DEBUG
1718			printk(OSST_DEB_MSG "%s:D: About to write pending fseq %d at fppos %d\n",
1719					  name, STp->frame_seq_number-1, STp->first_frame_position);
1720#endif
1721			SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE,
1722						      STp->timeout, MAX_RETRIES, 1);
1723			*aSRpnt = SRpnt;
1724
1725			if (STp->buffer->syscall_result) {		/* additional write error */
1726				if ((SRpnt->sense[ 2] & 0x0f) == 13 &&
1727				     SRpnt->sense[12]         ==  0 &&
1728				     SRpnt->sense[13]         ==  2) {
1729					printk(KERN_ERR
1730					       "%s:E: Volume overflow in write error recovery\n",
1731					       name);
1732					break;				/* hit end of tape = fail */
1733				}
1734				flag = 1;
1735			}
1736			else
1737				pending = 0;
1738
1739			continue;
1740		}
1741		if (STp->cur_frames == 0) {
1742#if DEBUG
1743			debugging = dbg;
1744			printk(OSST_DEB_MSG "%s:D: Wait re-write finished\n", name);
1745#endif
1746			if (STp->first_frame_position != expected) {
1747				printk(KERN_ERR "%s:A: Actual position %d - expected %d\n", 
1748						name, STp->first_frame_position, expected);
1749				return (-EIO);
1750			}
1751			return 0;
1752		}
1753#if DEBUG
1754		if (debugging) {
1755			printk(OSST_DEB_MSG "%s:D: Sleeping in re-write wait ready\n", name);
1756			printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
1757			debugging = 0;
1758		}
1759#endif
1760		schedule_timeout_interruptible(msecs_to_jiffies(100));
1761	}
1762	printk(KERN_ERR "%s:E: Failed to find valid tape media\n", name);
1763#if DEBUG
1764	debugging = dbg;
1765#endif
1766	return (-EIO);
1767}
1768
1769/*
1770 * Error recovery algorithm for the OnStream tape.
1771 */
1772
1773static int osst_write_error_recovery(struct osst_tape * STp, struct osst_request ** aSRpnt, int pending)
1774{
1775	struct osst_request * SRpnt  = * aSRpnt;
1776	struct st_partstat  * STps   = & STp->ps[STp->partition];
1777	char		    * name   = tape_name(STp);
1778	int		      retval = 0;
1779	int		      rw_state;
1780	unsigned int	      frame, skip;
1781
1782	rw_state = STps->rw;
1783
1784	if ((SRpnt->sense[ 2] & 0x0f) != 3
1785	  || SRpnt->sense[12]         != 12
1786	  || SRpnt->sense[13]         != 0) {
1787#if DEBUG
1788		printk(OSST_DEB_MSG "%s:D: Write error recovery cannot handle %02x:%02x:%02x\n", name,
1789			SRpnt->sense[2], SRpnt->sense[12], SRpnt->sense[13]);
1790#endif
1791		return (-EIO);
1792	}
1793	frame =	(SRpnt->sense[3] << 24) |
1794		(SRpnt->sense[4] << 16) |
1795		(SRpnt->sense[5] <<  8) |
1796		 SRpnt->sense[6];
1797	skip  =  SRpnt->sense[9];
1798 
1799#if DEBUG
1800	printk(OSST_DEB_MSG "%s:D: Detected physical bad frame at %u, advised to skip %d\n", name, frame, skip);
1801#endif
1802	osst_get_frame_position(STp, aSRpnt);
1803#if DEBUG
1804	printk(OSST_DEB_MSG "%s:D: reported frame positions: host = %d, tape = %d\n",
1805			name, STp->first_frame_position, STp->last_frame_position);
1806#endif
1807	switch (STp->write_type) {
1808	   case OS_WRITE_DATA:
1809	   case OS_WRITE_EOD:
1810	   case OS_WRITE_NEW_MARK:
1811		printk(KERN_WARNING 
1812			"%s:I: Relocating %d buffered logical frames from position %u to %u\n",
1813			name, STp->cur_frames, frame, (frame + skip > 3000 && frame < 3000)?3000:frame + skip);
1814		if (STp->os_fw_rev >= 10600)
1815			retval = osst_reposition_and_retry(STp, aSRpnt, frame, skip, pending);
1816		else
1817			retval = osst_read_back_buffer_and_rewrite(STp, aSRpnt, frame, skip, pending);
1818		printk(KERN_WARNING "%s:%s: %sWrite error%srecovered\n", name,
1819			       	retval?"E"    :"I",
1820			       	retval?""     :"Don't worry, ",
1821			       	retval?" not ":" ");
1822		break;
1823	   case OS_WRITE_LAST_MARK:
1824		printk(KERN_ERR "%s:E: Bad frame in update last marker, fatal\n", name);
1825		osst_set_frame_position(STp, aSRpnt, frame + STp->cur_frames + pending, 0);
1826		retval = -EIO;
1827		break;
1828	   case OS_WRITE_HEADER:
1829		printk(KERN_WARNING "%s:I: Bad frame in header partition, skipped\n", name);
1830		retval = osst_read_back_buffer_and_rewrite(STp, aSRpnt, frame, 1, pending);
1831		break;
1832	   default:
1833		printk(KERN_INFO "%s:I: Bad frame in filler, ignored\n", name);
1834		osst_set_frame_position(STp, aSRpnt, frame + STp->cur_frames + pending, 0);
1835	}
1836	osst_get_frame_position(STp, aSRpnt);
1837#if DEBUG
1838	printk(OSST_DEB_MSG "%s:D: Positioning complete, cur_frames %d, pos %d, tape pos %d\n", 
1839			name, STp->cur_frames, STp->first_frame_position, STp->last_frame_position);
1840	printk(OSST_DEB_MSG "%s:D: next logical frame to write: %d\n", name, STp->logical_blk_num);
1841#endif
1842	if (retval == 0) {
1843		STp->recover_count++;
1844		STp->recover_erreg++;
1845	} else
1846		STp->abort_count++;
1847
1848	STps->rw = rw_state;
1849	return retval;
1850}
1851
1852static int osst_space_over_filemarks_backward(struct osst_tape * STp, struct osst_request ** aSRpnt,
1853								 int mt_op, int mt_count)
1854{
1855	char  * name = tape_name(STp);
1856	int     cnt;
1857	int     last_mark_ppos = -1;
1858
1859#if DEBUG
1860	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_backwards %d %d\n", name, mt_op, mt_count);
1861#endif
1862	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1863#if DEBUG
1864		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_bwd\n", name);
1865#endif
1866		return -EIO;
1867	}
1868	if (STp->linux_media_version >= 4) {
1869		/*
1870		 * direct lookup in header filemark list
1871		 */
1872		cnt = ntohl(STp->buffer->aux->filemark_cnt);
1873		if (STp->header_ok                         && 
1874		    STp->header_cache != NULL              &&
1875		    (cnt - mt_count)  >= 0                 &&
1876		    (cnt - mt_count)   < OS_FM_TAB_MAX     &&
1877		    (cnt - mt_count)   < STp->filemark_cnt &&
1878		    STp->header_cache->dat_fm_tab.fm_tab_ent[cnt-1] == STp->buffer->aux->last_mark_ppos)
1879
1880			last_mark_ppos = ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt - mt_count]);
1881#if DEBUG
1882		if (STp->header_cache == NULL || (cnt - mt_count) < 0 || (cnt - mt_count) >= OS_FM_TAB_MAX)
1883			printk(OSST_DEB_MSG "%s:D: Filemark lookup fail due to %s\n", name,
1884			       STp->header_cache == NULL?"lack of header cache":"count out of range");
1885		else
1886			printk(OSST_DEB_MSG "%s:D: Filemark lookup: prev mark %d (%s), skip %d to %d\n",
1887				name, cnt,
1888				((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
1889				 (STp->header_cache->dat_fm_tab.fm_tab_ent[cnt-1] ==
1890					 STp->buffer->aux->last_mark_ppos))?"match":"error",
1891			       mt_count, last_mark_ppos);
1892#endif
1893		if (last_mark_ppos > 10 && last_mark_ppos < STp->eod_frame_ppos) {
1894			osst_position_tape_and_confirm(STp, aSRpnt, last_mark_ppos);
1895			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1896#if DEBUG
1897				printk(OSST_DEB_MSG 
1898					"%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1899#endif
1900				return (-EIO);
1901			}
1902			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
1903				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
1904						 name, last_mark_ppos);
1905				return (-EIO);
1906			}
1907			goto found;
1908		}
1909#if DEBUG
1910		printk(OSST_DEB_MSG "%s:D: Reverting to scan filemark backwards\n", name);
1911#endif
1912	}
1913	cnt = 0;
1914	while (cnt != mt_count) {
1915		last_mark_ppos = ntohl(STp->buffer->aux->last_mark_ppos);
1916		if (last_mark_ppos == -1)
1917			return (-EIO);
1918#if DEBUG
1919		printk(OSST_DEB_MSG "%s:D: Positioning to last mark at %d\n", name, last_mark_ppos);
1920#endif
1921		osst_position_tape_and_confirm(STp, aSRpnt, last_mark_ppos);
1922		cnt++;
1923		if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1924#if DEBUG
1925			printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1926#endif
1927			return (-EIO);
1928		}
1929		if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
1930			printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
1931					 name, last_mark_ppos);
1932			return (-EIO);
1933		}
1934	}
1935found:
1936	if (mt_op == MTBSFM) {
1937		STp->frame_seq_number++;
1938		STp->frame_in_buffer      = 0;
1939		STp->buffer->buffer_bytes = 0;
1940		STp->buffer->read_pointer = 0;
1941		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1942	}
1943	return 0;
1944}
1945
1946/*
1947 * ADRL 1.1 compatible "slow" space filemarks fwd version
1948 *
1949 * Just scans for the filemark sequentially.
1950 */
1951static int osst_space_over_filemarks_forward_slow(struct osst_tape * STp, struct osst_request ** aSRpnt,
1952								     int mt_op, int mt_count)
1953{
1954	int	cnt = 0;
1955#if DEBUG
1956	char  * name = tape_name(STp);
1957
1958	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_forward_slow %d %d\n", name, mt_op, mt_count);
1959#endif
1960	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1961#if DEBUG
1962		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_fwd\n", name);
1963#endif
1964		return (-EIO);
1965	}
1966	while (1) {
1967		if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1968#if DEBUG
1969			printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1970#endif
1971			return (-EIO);
1972		}
1973		if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER)
1974			cnt++;
1975		if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_EOD) {
1976#if DEBUG
1977			printk(OSST_DEB_MSG "%s:D: space_fwd: EOD reached\n", name);
1978#endif
1979			if (STp->first_frame_position > STp->eod_frame_ppos+1) {
1980#if DEBUG
1981				printk(OSST_DEB_MSG "%s:D: EOD position corrected (%d=>%d)\n",
1982					       	name, STp->eod_frame_ppos, STp->first_frame_position-1);
1983#endif
1984				STp->eod_frame_ppos = STp->first_frame_position-1;
1985			}
1986			return (-EIO);
1987		}
1988		if (cnt == mt_count)
1989			break;
1990		STp->frame_in_buffer = 0;
1991	}
1992	if (mt_op == MTFSF) {
1993		STp->frame_seq_number++;
1994		STp->frame_in_buffer      = 0;
1995		STp->buffer->buffer_bytes = 0;
1996		STp->buffer->read_pointer = 0;
1997		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1998	}
1999	return 0;
2000}
2001
2002/*
2003 * Fast linux specific version of OnStream FSF
2004 */
2005static int osst_space_over_filemarks_forward_fast(struct osst_tape * STp, struct osst_request ** aSRpnt,
2006								     int mt_op, int mt_count)
2007{
2008	char  * name = tape_name(STp);
2009	int	cnt  = 0,
2010		next_mark_ppos = -1;
2011
2012#if DEBUG
2013	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_forward_fast %d %d\n", name, mt_op, mt_count);
2014#endif
2015	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2016#if DEBUG
2017		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_fwd\n", name);
2018#endif
2019		return (-EIO);
2020	}
2021
2022	if (STp->linux_media_version >= 4) {
2023		/*
2024		 * direct lookup in header filemark list
2025		 */
2026		cnt = ntohl(STp->buffer->aux->filemark_cnt) - 1;
2027		if (STp->header_ok                         && 
2028		    STp->header_cache != NULL              &&
2029		    (cnt + mt_count)   < OS_FM_TAB_MAX     &&
2030		    (cnt + mt_count)   < STp->filemark_cnt &&
2031		    ((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
2032		     (STp->header_cache->dat_fm_tab.fm_tab_ent[cnt] == STp->buffer->aux->last_mark_ppos)))
2033
2034			next_mark_ppos = ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt + mt_count]);
2035#if DEBUG
2036		if (STp->header_cache == NULL || (cnt + mt_count) >= OS_FM_TAB_MAX)
2037			printk(OSST_DEB_MSG "%s:D: Filemark lookup fail due to %s\n", name,
2038			       STp->header_cache == NULL?"lack of header cache":"count out of range");
2039		else
2040			printk(OSST_DEB_MSG "%s:D: Filemark lookup: prev mark %d (%s), skip %d to %d\n",
2041			       name, cnt,
2042			       ((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
2043				(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt] ==
2044					 STp->buffer->aux->last_mark_ppos))?"match":"error",
2045			       mt_count, next_mark_ppos);
2046#endif
2047		if (next_mark_ppos <= 10 || next_mark_ppos > STp->eod_frame_ppos) {
2048#if DEBUG
2049			printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2050#endif
2051			return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count);
2052		} else {
2053			osst_position_tape_and_confirm(STp, aSRpnt, next_mark_ppos);
2054			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2055#if DEBUG
2056				printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n",
2057						 name);
2058#endif
2059				return (-EIO);
2060			}
2061			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2062				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
2063						 name, next_mark_ppos);
2064				return (-EIO);
2065			}
2066			if (ntohl(STp->buffer->aux->filemark_cnt) != cnt + mt_count) {
2067				printk(KERN_WARNING "%s:W: Expected to find marker %d at ppos %d, not %d\n",
2068						 name, cnt+mt_count, next_mark_ppos,
2069						 ntohl(STp->buffer->aux->filemark_cnt));
2070       				return (-EIO);
2071			}
2072		}
2073	} else {
2074		/*
2075		 * Find nearest (usually previous) marker, then jump from marker to marker
2076		 */
2077		while (1) {
2078			if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER)
2079				break;
2080			if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_EOD) {
2081#if DEBUG
2082				printk(OSST_DEB_MSG "%s:D: space_fwd: EOD reached\n", name);
2083#endif
2084				return (-EIO);
2085			}
2086			if (ntohl(STp->buffer->aux->filemark_cnt) == 0) {
2087				if (STp->first_mark_ppos == -1) {
2088#if DEBUG
2089					printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2090#endif
2091					return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count);
2092				}
2093				osst_position_tape_and_confirm(STp, aSRpnt, STp->first_mark_ppos);
2094				if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2095#if DEBUG
2096					printk(OSST_DEB_MSG
2097					       "%s:D: Couldn't get logical blk num in space_filemarks_fwd_fast\n",
2098					       name);
2099#endif
2100					return (-EIO);
2101				}
2102				if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2103					printk(KERN_WARNING "%s:W: Expected to find filemark at %d\n",
2104							 name, STp->first_mark_ppos);
2105					return (-EIO);
2106				}
2107			} else {
2108				if (osst_space_over_filemarks_backward(STp, aSRpnt, MTBSF, 1) < 0)
2109					return (-EIO);
2110				mt_count++;
2111			}
2112		}
2113		cnt++;
2114		while (cnt != mt_count) {
2115			next_mark_ppos = ntohl(STp->buffer->aux->next_mark_ppos);
2116			if (!next_mark_ppos || next_mark_ppos > STp->eod_frame_ppos) {
2117#if DEBUG
2118				printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2119#endif
2120				return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count - cnt);
2121			}
2122#if DEBUG
2123			else printk(OSST_DEB_MSG "%s:D: Positioning to next mark at %d\n", name, next_mark_ppos);
2124#endif
2125			osst_position_tape_and_confirm(STp, aSRpnt, next_mark_ppos);
2126			cnt++;
2127			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2128#if DEBUG
2129				printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n",
2130						 name);
2131#endif
2132				return (-EIO);
2133			}
2134			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2135				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
2136						 name, next_mark_ppos);
2137				return (-EIO);
2138			}
2139		}
2140	}
2141	if (mt_op == MTFSF) {
2142		STp->frame_seq_number++;
2143		STp->frame_in_buffer      = 0;
2144		STp->buffer->buffer_bytes = 0;
2145		STp->buffer->read_pointer = 0;
2146		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
2147	}
2148	return 0;
2149}
2150
2151/*
2152 * In debug mode, we want to see as many errors as possible
2153 * to test the error recovery mechanism.
2154 */
2155#if DEBUG
2156static void osst_set_retries(struct osst_tape * STp, struct osst_request ** aSRpnt, int retries)
2157{
2158	unsigned char		cmd[MAX_COMMAND_SIZE];
2159	struct osst_request   * SRpnt  = * aSRpnt;
2160	char		      * name   = tape_name(STp);
2161
2162	memset(cmd, 0, MAX_COMMAND_SIZE);
2163	cmd[0] = MODE_SELECT;
2164	cmd[1] = 0x10;
2165	cmd[4] = NUMBER_RETRIES_PAGE_LENGTH + MODE_HEADER_LENGTH;
2166
2167	(STp->buffer)->b_data[0] = cmd[4] - 1;
2168	(STp->buffer)->b_data[1] = 0;			/* Medium Type - ignoring */
2169	(STp->buffer)->b_data[2] = 0;			/* Reserved */
2170	(STp->buffer)->b_data[3] = 0;			/* Block Descriptor Length */
2171	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = NUMBER_RETRIES_PAGE | (1 << 7);
2172	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 2;
2173	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 4;
2174	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = retries;
2175
2176	if (debugging)
2177	    printk(OSST_DEB_MSG "%s:D: Setting number of retries on OnStream tape to %d\n", name, retries);
2178
2179	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2180	*aSRpnt = SRpnt;
2181
2182	if ((STp->buffer)->syscall_result)
2183	    printk (KERN_ERR "%s:D: Couldn't set retries to %d\n", name, retries);
2184}
2185#endif
2186
2187
2188static int osst_write_filemark(struct osst_tape * STp, struct osst_request ** aSRpnt)
2189{
2190	int	result;
2191	int	this_mark_ppos = STp->first_frame_position;
2192	int	this_mark_lbn  = STp->logical_blk_num;
2193#if DEBUG
2194	char  * name = tape_name(STp);
2195#endif
2196
2197	if (STp->raw) return 0;
2198
2199	STp->write_type = OS_WRITE_NEW_MARK;
2200#if DEBUG
2201	printk(OSST_DEB_MSG "%s:D: Writing Filemark %i at fppos %d (fseq %d, lblk %d)\n", 
2202	       name, STp->filemark_cnt, this_mark_ppos, STp->frame_seq_number, this_mark_lbn);
2203#endif
2204	STp->dirty = 1;
2205	result  = osst_flush_write_buffer(STp, aSRpnt);
2206	result |= osst_flush_drive_buffer(STp, aSRpnt);
2207	STp->last_mark_ppos = this_mark_ppos;
2208	STp->last_mark_lbn  = this_mark_lbn;
2209	if (STp->header_cache != NULL && STp->filemark_cnt < OS_FM_TAB_MAX)
2210		STp->header_cache->dat_fm_tab.fm_tab_ent[STp->filemark_cnt] = htonl(this_mark_ppos);
2211	if (STp->filemark_cnt++ == 0)
2212		STp->first_mark_ppos = this_mark_ppos;
2213	return result;
2214}
2215
2216static int osst_write_eod(struct osst_tape * STp, struct osst_request ** aSRpnt)
2217{
2218	int	result;
2219#if DEBUG
2220	char  * name = tape_name(STp);
2221#endif
2222
2223	if (STp->raw) return 0;
2224
2225	STp->write_type = OS_WRITE_EOD;
2226	STp->eod_frame_ppos = STp->first_frame_position;
2227#if DEBUG
2228	printk(OSST_DEB_MSG "%s:D: Writing EOD at fppos %d (fseq %d, lblk %d)\n", name,
2229			STp->eod_frame_ppos, STp->frame_seq_number, STp->logical_blk_num);
2230#endif
2231	STp->dirty = 1;
2232
2233	result  = osst_flush_write_buffer(STp, aSRpnt);	
2234	result |= osst_flush_drive_buffer(STp, aSRpnt);
2235	STp->eod_frame_lfa = --(STp->frame_seq_number);
2236	return result;
2237}
2238
2239static int osst_write_filler(struct osst_tape * STp, struct osst_request ** aSRpnt, int where, int count)
2240{
2241	char * name = tape_name(STp);
2242
2243#if DEBUG
2244	printk(OSST_DEB_MSG "%s:D: Reached onstream write filler group %d\n", name, where);
2245#endif
2246	osst_wait_ready(STp, aSRpnt, 60 * 5, 0);
2247	osst_set_frame_position(STp, aSRpnt, where, 0);
2248	STp->write_type = OS_WRITE_FILLER;
2249	while (count--) {
2250		memcpy(STp->buffer->b_data, "Filler", 6);
2251		STp->buffer->buffer_bytes = 6;
2252		STp->dirty = 1;
2253		if (osst_flush_write_buffer(STp, aSRpnt)) {
2254			printk(KERN_INFO "%s:I: Couldn't write filler frame\n", name);
2255			return (-EIO);
2256		}
2257	}
2258#if DEBUG
2259	printk(OSST_DEB_MSG "%s:D: Exiting onstream write filler group\n", name);
2260#endif
2261	return osst_flush_drive_buffer(STp, aSRpnt);
2262}
2263
2264static int __osst_write_header(struct osst_tape * STp, struct osst_request ** aSRpnt, int where, int count)
2265{
2266	char * name = tape_name(STp);
2267	int     result;
2268
2269#if DEBUG
2270	printk(OSST_DEB_MSG "%s:D: Reached onstream write header group %d\n", name, where);
2271#endif
2272	osst_wait_ready(STp, aSRpnt, 60 * 5, 0);
2273	osst_set_frame_position(STp, aSRpnt, where, 0);
2274	STp->write_type = OS_WRITE_HEADER;
2275	while (count--) {
2276		osst_copy_to_buffer(STp->buffer, (unsigned char *)STp->header_cache);
2277		STp->buffer->buffer_bytes = sizeof(os_header_t);
2278		STp->dirty = 1;
2279		if (osst_flush_write_buffer(STp, aSRpnt)) {
2280			printk(KERN_INFO "%s:I: Couldn't write header frame\n", name);
2281			return (-EIO);
2282		}
2283	}
2284	result = osst_flush_drive_buffer(STp, aSRpnt);
2285#if DEBUG
2286	printk(OSST_DEB_MSG "%s:D: Write onstream header group %s\n", name, result?"failed":"done");
2287#endif
2288	return result;
2289}
2290
2291static int osst_write_header(struct osst_tape * STp, struct osst_request ** aSRpnt, int locate_eod)
2292{
2293	os_header_t * header;
2294	int	      result;
2295	char        * name = tape_name(STp);
2296
2297#if DEBUG
2298	printk(OSST_DEB_MSG "%s:D: Writing tape header\n", name);
2299#endif
2300	if (STp->raw) return 0;
2301
2302	if (STp->header_cache == NULL) {
2303		if ((STp->header_cache = vmalloc(sizeof(os_header_t))) == NULL) {
2304			printk(KERN_ERR "%s:E: Failed to allocate header cache\n", name);
2305			return (-ENOMEM);
2306		}
2307		memset(STp->header_cache, 0, sizeof(os_header_t));
2308#if DEBUG
2309		printk(OSST_DEB_MSG "%s:D: Allocated and cleared memory for header cache\n", name);
2310#endif
2311	}
2312	if (STp->header_ok) STp->update_frame_cntr++;
2313	else                STp->update_frame_cntr = 0;
2314
2315	header = STp->header_cache;
2316	strcpy(header->ident_str, "ADR_SEQ");
2317	header->major_rev      = 1;
2318	header->minor_rev      = 4;
2319	header->ext_trk_tb_off = htons(17192);
2320	header->pt_par_num     = 1;
2321	header->partition[0].partition_num              = OS_DATA_PARTITION;
2322	header->partition[0].par_desc_ver               = OS_PARTITION_VERSION;
2323	header->partition[0].wrt_pass_cntr              = htons(STp->wrt_pass_cntr);
2324	header->partition[0].first_frame_ppos           = htonl(STp->first_data_ppos);
2325	header->partition[0].last_frame_ppos            = htonl(STp->capacity);
2326	header->partition[0].eod_frame_ppos             = htonl(STp->eod_frame_ppos);
2327	header->cfg_col_width                           = htonl(20);
2328	header->dat_col_width                           = htonl(1500);
2329	header->qfa_col_width                           = htonl(0);
2330	header->ext_track_tb.nr_stream_part             = 1;
2331	header->ext_track_tb.et_ent_sz                  = 32;
2332	header->ext_track_tb.dat_ext_trk_ey.et_part_num = 0;
2333	header->ext_track_tb.dat_ext_trk_ey.fmt         = 1;
2334	header->ext_track_tb.dat_ext_trk_ey.fm_tab_off  = htons(17736);
2335	header->ext_track_tb.dat_ext_trk_ey.last_hlb_hi = 0;
2336	header->ext_track_tb.dat_ext_trk_ey.last_hlb    = htonl(STp->eod_frame_lfa);
2337	header->ext_track_tb.dat_ext_trk_ey.last_pp	= htonl(STp->eod_frame_ppos);
2338	header->dat_fm_tab.fm_part_num                  = 0;
2339	header->dat_fm_tab.fm_tab_ent_sz                = 4;
2340	header->dat_fm_tab.fm_tab_ent_cnt               = htons(STp->filemark_cnt<OS_FM_TAB_MAX?
2341								STp->filemark_cnt:OS_FM_TAB_MAX);
2342
2343	result  = __osst_write_header(STp, aSRpnt, 0xbae, 5);
2344	if (STp->update_frame_cntr == 0)
2345		    osst_write_filler(STp, aSRpnt, 0xbb3, 5);
2346	result &= __osst_write_header(STp, aSRpnt,     5, 5);
2347
2348	if (locate_eod) {
2349#if DEBUG
2350		printk(OSST_DEB_MSG "%s:D: Locating back to eod frame addr %d\n", name, STp->eod_frame_ppos);
2351#endif
2352		osst_set_frame_position(STp, aSRpnt, STp->eod_frame_ppos, 0);
2353	}
2354	if (result)
2355		printk(KERN_ERR "%s:E: Write header failed\n", name);
2356	else {
2357		memcpy(STp->application_sig, "LIN4", 4);
2358		STp->linux_media         = 1;
2359		STp->linux_media_version = 4;
2360		STp->header_ok           = 1;
2361	}
2362	return result;
2363}
2364
2365static int osst_reset_header(struct osst_tape * STp, struct osst_request ** aSRpnt)
2366{
2367	if (STp->header_cache != NULL)
2368		memset(STp->header_cache, 0, sizeof(os_header_t));
2369
2370	STp->logical_blk_num = STp->frame_seq_number = 0;
2371	STp->frame_in_buffer = 0;
2372	STp->eod_frame_ppos = STp->first_data_ppos = 0x0000000A;
2373	STp->filemark_cnt = 0;
2374	STp->first_mark_ppos = STp->last_mark_ppos = STp->last_mark_lbn = -1;
2375	return osst_write_header(STp, aSRpnt, 1);
2376}
2377
2378static int __osst_analyze_headers(struct osst_tape * STp, struct osst_request ** aSRpnt, int ppos)
2379{
2380	char        * name = tape_name(STp);
2381	os_header_t * header;
2382	os_aux_t    * aux;
2383	char          id_string[8];
2384	int	      linux_media_version,
2385		      update_frame_cntr;
2386
2387	if (STp->raw)
2388		return 1;
2389
2390	if (ppos == 5 || ppos == 0xbae || STp->buffer->syscall_result) {
2391		if (osst_set_frame_position(STp, aSRpnt, ppos, 0))
2392			printk(KERN_WARNING "%s:W: Couldn't position tape\n", name);
2393		osst_wait_ready(STp, aSRpnt, 60 * 15, 0);
2394		if (osst_initiate_read (STp, aSRpnt)) {
2395			printk(KERN_WARNING "%s:W: Couldn't initiate read\n", name);
2396			return 0;
2397		}
2398	}
2399	if (osst_read_frame(STp, aSRpnt, 180)) {
2400#if DEBUG
2401		printk(OSST_DEB_MSG "%s:D: Couldn't read header frame\n", name);
2402#endif
2403		return 0;
2404	}
2405	header = (os_header_t *) STp->buffer->b_data;	/* warning: only first segment addressable */
2406	aux = STp->buffer->aux;
2407	if (aux->frame_type != OS_FRAME_TYPE_HEADER) {
2408#if DEBUG
2409		printk(OSST_DEB_MSG "%s:D: Skipping non-header frame (%d)\n", name, ppos);
2410#endif
2411		return 0;
2412	}
2413	if (ntohl(aux->frame_seq_num)              != 0                   ||
2414	    ntohl(aux->logical_blk_num)            != 0                   ||
2415	          aux->partition.partition_num     != OS_CONFIG_PARTITION ||
2416	    ntohl(aux->partition.first_frame_ppos) != 0                   ||
2417	    ntohl(aux->partition.last_frame_ppos)  != 0xbb7               ) {
2418#if DEBUG
2419		printk(OSST_DEB_MSG "%s:D: Invalid header frame (%d,%d,%d,%d,%d)\n", name,
2420				ntohl(aux->frame_seq_num), ntohl(aux->logical_blk_num),
2421			       	aux->partition.partition_num, ntohl(aux->partition.first_frame_ppos),
2422			       	ntohl(aux->partition.last_frame_ppos));
2423#endif
2424		return 0;
2425	}
2426	if (strncmp(header->ident_str, "ADR_SEQ", 7) != 0 &&
2427	    strncmp(header->ident_str, "ADR-SEQ", 7) != 0) {
2428		strlcpy(id_string, header->ident_str, 8);
2429#if DEBUG
2430		printk(OSST_DEB_MSG "%s:D: Invalid header identification string %s\n", name, id_string);
2431#endif
2432		return 0;
2433	}
2434	update_frame_cntr = ntohl(aux->update_frame_cntr);
2435	if (update_frame_cntr < STp->update_frame_cntr) {
2436#if DEBUG
2437		printk(OSST_DEB_MSG "%s:D: Skipping frame %d with update_frame_counter %d<%d\n",
2438				   name, ppos, update_frame_cntr, STp->update_frame_cntr);
2439#endif
2440		return 0;
2441	}
2442	if (header->major_rev != 1 || header->minor_rev != 4 ) {
2443#if DEBUG
2444		printk(OSST_DEB_MSG "%s:D: %s revision %d.%d detected (1.4 supported)\n", 
2445				 name, (header->major_rev != 1 || header->minor_rev < 2 || 
2446				       header->minor_rev  > 4 )? "Invalid" : "Warning:",
2447				 header->major_rev, header->minor_rev);
2448#endif
2449		if (header->major_rev != 1 || header->minor_rev < 2 || header->minor_rev > 4)
2450			return 0;
2451	}
2452#if DEBUG
2453	if (header->pt_par_num != 1)
2454		printk(KERN_INFO "%s:W: %d partitions defined, only one supported\n", 
2455				 name, header->pt_par_num);
2456#endif
2457	memcpy(id_string, aux->application_sig, 4);
2458	id_string[4] = 0;
2459	if (memcmp(id_string, "LIN", 3) == 0) {
2460		STp->linux_media = 1;
2461		linux_media_version = id_string[3] - '0';
2462		if (linux_media_version != 4)
2463			printk(KERN_INFO "%s:I: Linux media version %d detected (current 4)\n",
2464					 name, linux_media_version);
2465	} else {
2466		printk(KERN_WARNING "%s:W: Non Linux media detected (%s)\n", name, id_string);
2467		return 0;
2468	}
2469	if (linux_media_version < STp->linux_media_version) {
2470#if DEBUG
2471		printk(OSST_DEB_MSG "%s:D: Skipping frame %d with linux_media_version %d\n",
2472				  name, ppos, linux_media_version);
2473#endif
2474		return 0;
2475	}
2476	if (linux_media_version > STp->linux_media_version) {
2477#if DEBUG
2478		printk(OSST_DEB_MSG "%s:D: Frame %d sets linux_media_version to %d\n",
2479				   name, ppos, linux_media_version);
2480#endif
2481		memcpy(STp->application_sig, id_string, 5);
2482		STp->linux_media_version = linux_media_version;
2483		STp->update_frame_cntr = -1;
2484	}
2485	if (update_frame_cntr > STp->update_frame_cntr) {
2486#if DEBUG
2487		printk(OSST_DEB_MSG "%s:D: Frame %d sets update_frame_counter to %d\n",
2488				   name, ppos, update_frame_cntr);
2489#endif
2490		if (STp->header_cache == NULL) {
2491			if ((STp->header_cache = vmalloc(sizeof(os_header_t))) == NULL) {
2492				printk(KERN_ERR "%s:E: Failed to allocate header cache\n", name);
2493				return 0;
2494			}
2495#if DEBUG
2496			printk(OSST_DEB_MSG "%s:D: Allocated memory for header cache\n", name);
2497#endif
2498		}
2499		osst_copy_from_buffer(STp->buffer, (unsigned char *)STp->header_cache);
2500		header = STp->header_cache;	/* further accesses from cached (full) copy */
2501
2502		STp->wrt_pass_cntr     = ntohs(header->partition[0].wrt_pass_cntr);
2503		STp->first_data_ppos   = ntohl(header->partition[0].first_frame_ppos);
2504		STp->eod_frame_ppos    = ntohl(header->partition[0].eod_frame_ppos);
2505		STp->eod_frame_lfa     = ntohl(header->ext_track_tb.dat_ext_trk_ey.last_hlb);
2506		STp->filemark_cnt      = ntohl(aux->filemark_cnt);
2507		STp->first_mark_ppos   = ntohl(aux->next_mark_ppos);
2508		STp->last_mark_ppos    = ntohl(aux->last_mark_ppos);
2509		STp->last_mark_lbn     = ntohl(aux->last_mark_lbn);
2510		STp->update_frame_cntr = update_frame_cntr;
2511#if DEBUG
2512	printk(OSST_DEB_MSG "%s:D: Detected write pass %d, update frame counter %d, filemark counter %d\n",
2513			  name, STp->wrt_pass_cntr, STp->update_frame_cntr, STp->filemark_cnt);
2514	printk(OSST_DEB_MSG "%s:D: first data frame on tape = %d, last = %d, eod frame = %d\n", name,
2515			  STp->first_data_ppos,
2516			  ntohl(header->partition[0].last_frame_ppos),
2517			  ntohl(header->partition[0].eod_frame_ppos));
2518	printk(OSST_DEB_MSG "%s:D: first mark on tape = %d, last = %d, eod frame = %d\n", 
2519			  name, STp->first_mark_ppos, STp->last_mark_ppos, STp->eod_frame_ppos);
2520#endif
2521		if (header->minor_rev < 4 && STp->linux_media_version == 4) {
2522#if DEBUG
2523			printk(OSST_DEB_MSG "%s:D: Moving filemark list to ADR 1.4 location\n", name);
2524#endif
2525			memcpy((void *)header->dat_fm_tab.fm_tab_ent, 
2526			       (void *)header->old_filemark_list, sizeof(header->dat_fm_tab.fm_tab_ent));
2527			memset((void *)header->old_filemark_list, 0, sizeof(header->old_filemark_list));
2528		}
2529		if (header->minor_rev == 4   &&
2530		    (header->ext_trk_tb_off                          != htons(17192)               ||
2531		     header->partition[0].partition_num              != OS_DATA_PARTITION          ||
2532		     header->partition[0].par_desc_ver               != OS_PARTITION_VERSION       ||
2533		     header->partition[0].last_frame_ppos            != htonl(STp->capacity)       ||
2534		     header->cfg_col_width                           != htonl(20)                  ||
2535		     header->dat_col_width                           != htonl(1500)                ||
2536		     header->qfa_col_width                           != htonl(0)                   ||
2537		     header->ext_track_tb.nr_stream_part             != 1                          ||
2538		     header->ext_track_tb.et_ent_sz                  != 32                         ||
2539		     header->ext_track_tb.dat_ext_trk_ey.et_part_num != OS_DATA_PARTITION          ||
2540		     header->ext_track_tb.dat_ext_trk_ey.fmt         != 1                          ||
2541		     header->ext_track_tb.dat_ext_trk_ey.fm_tab_off  != htons(17736)               ||
2542		     header->ext_track_tb.dat_ext_trk_ey.last_hlb_hi != 0                          ||
2543		     header->ext_track_tb.dat_ext_trk_ey.last_pp     != htonl(STp->eod_frame_ppos) ||
2544		     header->dat_fm_tab.fm_part_num                  != OS_DATA_PARTITION          ||
2545		     header->dat_fm_tab.fm_tab_ent_sz                != 4                          ||
2546		     header->dat_fm_tab.fm_tab_ent_cnt               !=
2547			     htons(STp->filemark_cnt<OS_FM_TAB_MAX?STp->filemark_cnt:OS_FM_TAB_MAX)))
2548			printk(KERN_WARNING "%s:W: Failed consistency check ADR 1.4 format\n", name);
2549
2550	}
2551
2552	return 1;
2553}
2554
2555static int osst_analyze_headers(struct osst_tape * STp, struct osst_request ** aSRpnt)
2556{
2557	int	position, ppos;
2558	int	first, last;
2559	int	valid = 0;
2560	char  * name  = tape_name(STp);
2561
2562	position = osst_get_frame_position(STp, aSRpnt);
2563
2564	if (STp->raw) {
2565		STp->header_ok = STp->linux_media = 1;
2566		STp->linux_media_version = 0;
2567		return 1;
2568	}
2569	STp->header_ok = STp->linux_media = STp->linux_media_version = 0;
2570	STp->wrt_pass_cntr = STp->update_frame_cntr = -1;
2571	STp->eod_frame_ppos = STp->first_data_ppos = -1;
2572	STp->first_mark_ppos = STp->last_mark_ppos = STp->last_mark_lbn = -1;
2573#if DEBUG
2574	printk(OSST_DEB_MSG "%s:D: Reading header\n", name);
2575#endif
2576
2577	/* optimization for speed - if we are positioned at ppos 10, read second group first  */	
2578	/* TODO try the ADR 1.1 locations for the second group if we have no valid one yet... */
2579
2580	first = position==10?0xbae: 5;
2581	last  = position==10?0xbb3:10;
2582
2583	for (ppos = first; ppos < last; ppos++)
2584		if (__osst_analyze_headers(STp, aSRpnt, ppos))
2585			valid = 1;
2586
2587	first = position==10? 5:0xbae;
2588	last  = position==10?10:0xbb3;
2589
2590	for (ppos = first; ppos < last; ppos++)
2591		if (__osst_analyze_headers(STp, aSRpnt, ppos))
2592			valid = 1;
2593
2594	if (!valid) {
2595		printk(KERN_ERR "%s:E: Failed to find valid ADRL header, new media?\n", name);
2596		STp->eod_frame_ppos = STp->first_data_ppos = 0;
2597		osst_set_frame_position(STp, aSRpnt, 10, 0);
2598		return 0;
2599	}
2600	if (position <= STp->first_data_ppos) {
2601		position = STp->first_data_ppos;
2602		STp->ps[0].drv_file = STp->ps[0].drv_block = STp->frame_seq_number = STp->logical_blk_num = 0;
2603	}
2604	osst_set_frame_position(STp, aSRpnt, position, 0);
2605	STp->header_ok = 1;
2606
2607	return 1;
2608}
2609
2610static int osst_verify_position(struct osst_tape * STp, struct osst_request ** aSRpnt)
2611{
2612	int	frame_position  = STp->first_frame_position;
2613	int	frame_seq_numbr = STp->frame_seq_number;
2614	int	logical_blk_num = STp->logical_blk_num;
2615       	int	halfway_frame   = STp->frame_in_buffer;
2616	int	read_pointer    = STp->buffer->read_pointer;
2617	int	prev_mark_ppos  = -1;
2618	int	actual_mark_ppos, i, n;
2619#if DEBUG
2620	char  * name = tape_name(STp);
2621
2622	printk(OSST_DEB_MSG "%s:D: Verify that the tape is really the one we think before writing\n", name);
2623#endif
2624	osst_set_frame_position(STp, aSRpnt, frame_position - 1, 0);
2625	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2626#if DEBUG
2627		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in verify_position\n", name);
2628#endif
2629		return (-EIO);
2630	}
2631	if (STp->linux_media_version >= 4) {
2632		for (i=0; i<STp->filemark_cnt; i++)
2633			if ((n=ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[i])) < frame_position)
2634				prev_mark_ppos = n;
2635	} else
2636		prev_mark_ppos = frame_position - 1;  /* usually - we don't really know */
2637	actual_mark_ppos = STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER ?
2638				frame_position - 1 : ntohl(STp->buffer->aux->last_mark_ppos);
2639	if (frame_position  != STp->first_frame_position                   ||
2640	    frame_seq_numbr != STp->frame_seq_number + (halfway_frame?0:1) ||
2641	    prev_mark_ppos  != actual_mark_ppos                            ) {
2642#if DEBUG
2643		printk(OSST_DEB_MSG "%s:D: Block mismatch: fppos %d-%d, fseq %d-%d, mark %d-%d\n", name,
2644				  STp->first_frame_position, frame_position, 
2645				  STp->frame_seq_number + (halfway_frame?0:1),
2646				  frame_seq_numbr, actual_mark_ppos, prev_mark_ppos);
2647#endif
2648		return (-EIO);
2649	}
2650	if (halfway_frame) {
2651		/* prepare buffer for append and rewrite on top of original */
2652		osst_set_frame_position(STp, aSRpnt, frame_position - 1, 0);
2653		STp->buffer->buffer_bytes  = read_pointer;
2654		STp->ps[STp->partition].rw = ST_WRITING;
2655		STp->dirty                 = 1;
2656	}
2657	STp->frame_in_buffer  = halfway_frame;
2658	STp->frame_seq_number = frame_seq_numbr;
2659	STp->logical_blk_num  = logical_blk_num;
2660	return 0;
2661}
2662
2663/* Acc. to OnStream, the vers. numbering is the following:
2664 * X.XX for released versions (X=digit), 
2665 * XXXY for unreleased versions (Y=letter)
2666 * Ordering 1.05 < 106A < 106B < ...  < 106a < ... < 1.06
2667 * This fn makes monoton numbers out of this scheme ...
2668 */
2669static unsigned int osst_parse_firmware_rev (const char * str)
2670{
2671	if (str[1] == '.') {
2672		return (str[0]-'0')*10000
2673			+(str[2]-'0')*1000
2674			+(str[3]-'0')*100;
2675	} else {
2676		return (str[0]-'0')*10000
2677			+(str[1]-'0')*1000
2678			+(str[2]-'0')*100 - 100
2679			+(str[3]-'@');
2680	}
2681}
2682
2683/*
2684 * Configure the OnStream SCII tape drive for default operation
2685 */
2686static int osst_configure_onstream(struct osst_tape *STp, struct osst_request ** aSRpnt)
2687{
2688	unsigned char                  cmd[MAX_COMMAND_SIZE];
2689	char                         * name = tape_name(STp);
2690	struct osst_request          * SRpnt = * aSRpnt;
2691	osst_mode_parameter_header_t * header;
2692	osst_block_size_page_t       * bs;
2693	osst_capabilities_page_t     * cp;
2694	osst_tape_paramtr_page_t     * prm;
2695	int                            drive_buffer_size;
2696
2697	if (STp->ready != ST_READY) {
2698#if DEBUG
2699	    printk(OSST_DEB_MSG "%s:D: Not Ready\n", name);
2700#endif
2701	    return (-EIO);
2702	}
2703	
2704	if (STp->os_fw_rev < 10600) {
2705	    printk(KERN_INFO "%s:I: Old OnStream firmware revision detected (%s),\n", name, STp->device->rev);
2706	    printk(KERN_INFO "%s:I: an upgrade to version 1.06 or above is recommended\n", name);
2707	}
2708
2709	/*
2710	 * Configure 32.5KB (data+aux) frame size.
2711         * Get the current frame size from the block size mode page
2712	 */
2713	memset(cmd, 0, MAX_COMMAND_SIZE);
2714	cmd[0] = MODE_SENSE;
2715	cmd[1] = 8;
2716	cmd[2] = BLOCK_SIZE_PAGE;
2717	cmd[4] = BLOCK_SIZE_PAGE_LENGTH + MODE_HEADER_LENGTH;
2718
2719	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2720	if (SRpnt == NULL) {
2721#if DEBUG
2722 	    printk(OSST_DEB_MSG "osst :D: Busy\n");
2723#endif
2724	    return (-EBUSY);
2725	}
2726	*aSRpnt = SRpnt;
2727	if ((STp->buffer)->syscall_result != 0) {
2728	    printk (KERN_ERR "%s:E: Can't get tape block size mode page\n", name);
2729	    return (-EIO);
2730	}
2731
2732	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2733	bs = (osst_block_size_page_t *) ((STp->buffer)->b_data + sizeof(osst_mode_parameter_header_t) + header->bdl);
2734
2735#if DEBUG
2736	printk(OSST_DEB_MSG "%s:D: 32KB play back: %s\n",   name, bs->play32     ? "Yes" : "No");
2737	printk(OSST_DEB_MSG "%s:D: 32.5KB play back: %s\n", name, bs->play32_5   ? "Yes" : "No");
2738	printk(OSST_DEB_MSG "%s:D: 32KB record: %s\n",      name, bs->record32   ? "Yes" : "No");
2739	printk(OSST_DEB_MSG "%s:D: 32.5KB record: %s\n",    name, bs->record32_5 ? "Yes" : "No");
2740#endif
2741
2742	/*
2743	 * Configure default auto columns mode, 32.5KB transfer mode
2744	 */ 
2745	bs->one = 1;
2746	bs->play32 = 0;
2747	bs->play32_5 = 1;
2748	bs->record32 = 0;
2749	bs->record32_5 = 1;
2750
2751	memset(cmd, 0, MAX_COMMAND_SIZE);
2752	cmd[0] = MODE_SELECT;
2753	cmd[1] = 0x10;
2754	cmd[4] = BLOCK_SIZE_PAGE_LENGTH + MODE_HEADER_LENGTH;
2755
2756	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2757	*aSRpnt = SRpnt;
2758	if ((STp->buffer)->syscall_result != 0) {
2759	    printk (KERN_ERR "%s:E: Couldn't set tape block size mode page\n", name);
2760	    return (-EIO);
2761	}
2762
2763#if DEBUG
2764	printk(KERN_INFO "%s:D: Drive Block Size changed to 32.5K\n", name);
2765	 /*
2766	 * In debug mode, we want to see as many errors as possible
2767	 * to test the error recovery mechanism.
2768	 */
2769	osst_set_retries(STp, aSRpnt, 0);
2770	SRpnt = * aSRpnt;
2771#endif
2772
2773	/*
2774	 * Set vendor name to 'LIN4' for "Linux support version 4".
2775	 */
2776
2777	memset(cmd, 0, MAX_COMMAND_SIZE);
2778	cmd[0] = MODE_SELECT;
2779	cmd[1] = 0x10;
2780	cmd[4] = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH;
2781
2782	header->mode_data_length = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH - 1;
2783	header->medium_type      = 0;	/* Medium Type - ignoring */
2784	header->dsp              = 0;	/* Reserved */
2785	header->bdl              = 0;	/* Block Descriptor Length */
2786	
2787	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = VENDOR_IDENT_PAGE | (1 << 7);
2788	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 6;
2789	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 'L';
2790	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = 'I';
2791	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 4] = 'N';
2792	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 5] = '4';
2793	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 6] = 0;
2794	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 7] = 0;
2795
2796	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2797	*aSRpnt = SRpnt;
2798
2799	if ((STp->buffer)->syscall_result != 0) {
2800	    printk (KERN_ERR "%s:E: Couldn't set vendor name to %s\n", name, 
2801			(char *) ((STp->buffer)->b_data + MODE_HEADER_LENGTH + 2));
2802	    return (-EIO);
2803	}
2804
2805	memset(cmd, 0, MAX_COMMAND_SIZE);
2806	cmd[0] = MODE_SENSE;
2807	cmd[1] = 8;
2808	cmd[2] = CAPABILITIES_PAGE;
2809	cmd[4] = CAPABILITIES_PAGE_LENGTH + MODE_HEADER_LENGTH;
2810
2811	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2812	*aSRpnt = SRpnt;
2813
2814	if ((STp->buffer)->syscall_result != 0) {
2815	    printk (KERN_ERR "%s:E: Can't get capabilities page\n", name);
2816	    return (-EIO);
2817	}
2818
2819	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2820	cp     = (osst_capabilities_page_t    *) ((STp->buffer)->b_data +
2821		 sizeof(osst_mode_parameter_header_t) + header->bdl);
2822
2823	drive_buffer_size = ntohs(cp->buffer_size) / 2;
2824
2825	memset(cmd, 0, MAX_COMMAND_SIZE);
2826	cmd[0] = MODE_SENSE;
2827	cmd[1] = 8;
2828	cmd[2] = TAPE_PARAMTR_PAGE;
2829	cmd[4] = TAPE_PARAMTR_PAGE_LENGTH + MODE_HEADER_LENGTH;
2830
2831	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2832	*aSRpnt = SRpnt;
2833
2834	if ((STp->buffer)->syscall_result != 0) {
2835	    printk (KERN_ERR "%s:E: Can't get tape parameter page\n", name);
2836	    return (-EIO);
2837	}
2838
2839	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2840	prm    = (osst_tape_paramtr_page_t    *) ((STp->buffer)->b_data +
2841		 sizeof(osst_mode_parameter_header_t) + header->bdl);
2842
2843	STp->density  = prm->density;
2844	STp->capacity = ntohs(prm->segtrk) * ntohs(prm->trks);
2845#if DEBUG
2846	printk(OSST_DEB_MSG "%s:D: Density %d, tape length: %dMB, drive buffer size: %dKB\n",
2847			  name, STp->density, STp->capacity / 32, drive_buffer_size);
2848#endif
2849
2850	return 0;
2851	
2852}
2853
2854
2855/* Step over EOF if it has been inadvertently crossed (ioctl not used because
2856   it messes up the block number). */
2857static int cross_eof(struct osst_tape *STp, struct osst_request ** aSRpnt, int forward)
2858{
2859	int	result;
2860	char  * name = tape_name(STp);
2861
2862#if DEBUG
2863	if (debugging)
2864		printk(OSST_DEB_MSG "%s:D: Stepping over filemark %s.\n",
2865	   			  name, forward ? "forward" : "backward");
2866#endif
2867
2868	if (forward) {
2869	   /* assumes that the filemark is already read by the drive, so this is low cost */
2870	   result = osst_space_over_filemarks_forward_slow(STp, aSRpnt, MTFSF, 1);
2871	}
2872	else
2873	   /* assumes this is only called if we just read the filemark! */
2874	   result = osst_seek_logical_blk(STp, aSRpnt, STp->logical_blk_num - 1);
2875
2876	if (result < 0)
2877	   printk(KERN_WARNING "%s:W: Stepping over filemark %s failed.\n",
2878				name, forward ? "forward" : "backward");
2879
2880	return result;
2881}
2882
2883
2884/* Get the tape position. */
2885
2886static int osst_get_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt)
2887{
2888	unsigned char		scmd[MAX_COMMAND_SIZE];
2889	struct osst_request   * SRpnt;
2890	int			result = 0;
2891	char    	      * name   = tape_name(STp);
2892
2893	/* KG: We want to be able to use it for checking Write Buffer availability
2894	 *  and thus don't want to risk to overwrite anything. Exchange buffers ... */
2895	char		mybuf[24];
2896	char	      * olddata = STp->buffer->b_data;
2897	int		oldsize = STp->buffer->buffer_size;
2898
2899	if (STp->ready != ST_READY) return (-EIO);
2900
2901	memset (scmd, 0, MAX_COMMAND_SIZE);
2902	scmd[0] = READ_POSITION;
2903
2904	STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
2905	SRpnt = osst_do_scsi(*aSRpnt, STp, scmd, 20, DMA_FROM_DEVICE,
2906				      STp->timeout, MAX_RETRIES, 1);
2907	if (!SRpnt) {
2908		STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
2909		return (-EBUSY);
2910	}
2911	*aSRpnt = SRpnt;
2912
2913	if (STp->buffer->syscall_result)
2914		result = ((SRpnt->sense[2] & 0x0f) == 3) ? -EIO : -EINVAL;	/* 3: Write Error */
2915
2916	if (result == -EINVAL)
2917		printk(KERN_ERR "%s:E: Can't read tape position.\n", name);
2918	else {
2919		if (result == -EIO) {	/* re-read position - this needs to preserve media errors */
2920			unsigned char mysense[16];
2921			memcpy (mysense, SRpnt->sense, 16);
2922			memset (scmd, 0, MAX_COMMAND_SIZE);
2923			scmd[0] = READ_POSITION;
2924			STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
2925			SRpnt = osst_do_scsi(SRpnt, STp, scmd, 20, DMA_FROM_DEVICE,
2926						    STp->timeout, MAX_RETRIES, 1);
2927#if DEBUG
2928			printk(OSST_DEB_MSG "%s:D: Reread position, reason=[%02x:%02x:%02x], result=[%s%02x:%02x:%02x]\n",
2929					name, mysense[2], mysense[12], mysense[13], STp->buffer->syscall_result?"":"ok:",
2930					SRpnt->sense[2],SRpnt->sense[12],SRpnt->sense[13]);
2931#endif
2932			if (!STp->buffer->syscall_result)
2933				memcpy (SRpnt->sense, mysense, 16);
2934			else
2935				printk(KERN_WARNING "%s:W: Double error in get position\n", name);
2936		}
2937		STp->first_frame_position = ((STp->buffer)->b_data[4] << 24)
2938					  + ((STp->buffer)->b_data[5] << 16)
2939					  + ((STp->buffer)->b_data[6] << 8)
2940					  +  (STp->buffer)->b_data[7];
2941		STp->last_frame_position  = ((STp->buffer)->b_data[ 8] << 24)
2942					  + ((STp->buffer)->b_data[ 9] << 16)
2943					  + ((STp->buffer)->b_data[10] <<  8)
2944					  +  (STp->buffer)->b_data[11];
2945		STp->cur_frames           =  (STp->buffer)->b_data[15];
2946#if DEBUG
2947		if (debugging) {
2948			printk(OSST_DEB_MSG "%s:D: Drive Positions: host %d, tape %d%s, buffer %d\n", name,
2949					    STp->first_frame_position, STp->last_frame_position,
2950					    ((STp->buffer)->b_data[0]&0x80)?" (BOP)":
2951					    ((STp->buffer)->b_data[0]&0x40)?" (EOP)":"",
2952					    STp->cur_frames);
2953		}
2954#endif
2955		if (STp->cur_frames == 0 && STp->first_frame_position != STp->last_frame_position) {
2956#if DEBUG
2957			printk(OSST_DEB_MSG "%s:D: Correcting read position %d, %d, %d\n", name,
2958					STp->first_frame_position, STp->last_frame_position, STp->cur_frames);
2959#endif
2960			STp->first_frame_position = STp->last_frame_position;
2961		}
2962	}
2963	STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
2964
2965	return (result == 0 ? STp->first_frame_position : result);
2966}
2967
2968
2969/* Set the tape block */
2970static int osst_set_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt, int ppos, int skip)
2971{
2972	unsigned char		scmd[MAX_COMMAND_SIZE];
2973	struct osst_request   * SRpnt;
2974	struct st_partstat    * STps;
2975	int			result = 0;
2976	int			pp     = (ppos == 3000 && !skip)? 0 : ppos;
2977	char		      * name   = tape_name(STp);
2978
2979	if (STp->ready != ST_READY) return (-EIO);
2980
2981	STps = &(STp->ps[STp->partition]);
2982
2983	if (ppos < 0 || ppos > STp->capacity) {
2984		printk(KERN_WARNING "%s:W: Reposition request %d out of range\n", name, ppos);
2985		pp = ppos = ppos < 0 ? 0 : (STp->capacity - 1);
2986		result = (-EINVAL);
2987	}
2988
2989	do {
2990#if DEBUG
2991		if (debugging)
2992			printk(OSST_DEB_MSG "%s:D: Setting ppos to %d.\n", name, pp);
2993#endif
2994		memset (scmd, 0, MAX_COMMAND_SIZE);
2995		scmd[0] = SEEK_10;
2996		scmd[1] = 1;
2997		scmd[3] = (pp >> 24);
2998		scmd[4] = (pp >> 16);
2999		scmd[5] = (pp >> 8);
3000		scmd[6] =  pp;
3001		if (skip)
3002			scmd[9] = 0x80;
3003
3004		SRpnt = osst_do_scsi(*aSRpnt, STp, scmd, 0, DMA_NONE, STp->long_timeout,
3005								MAX_RETRIES, 1);
3006		if (!SRpnt)
3007			return (-EBUSY);
3008		*aSRpnt  = SRpnt;
3009
3010		if ((STp->buffer)->syscall_result != 0) {
3011#if DEBUG
3012			printk(OSST_DEB_MSG "%s:D: SEEK command from %d to %d failed.\n",
3013					name, STp->first_frame_position, pp);
3014#endif
3015			result = (-EIO);
3016		}
3017		if (pp != ppos)
3018			osst_wait_ready(STp, aSRpnt, 5 * 60, OSST_WAIT_POSITION_COMPLETE);
3019	} while ((pp != ppos) && (pp = ppos));
3020	STp->first_frame_position = STp->last_frame_position = ppos;
3021	STps->eof = ST_NOEOF;
3022	STps->at_sm = 0;
3023	STps->rw = ST_IDLE;
3024	STp->frame_in_buffer = 0;
3025	return result;
3026}
3027
3028static int osst_write_trailer(struct osst_tape *STp, struct osst_request ** aSRpnt, int leave_at_EOT)
3029{
3030	struct st_partstat * STps = &(STp->ps[STp->partition]);
3031	int result = 0;
3032
3033	if (STp->write_type != OS_WRITE_NEW_MARK) {
3034		/* true unless the user wrote the filemark for us */
3035		result = osst_flush_drive_buffer(STp, aSRpnt);
3036		if (result < 0) goto out;
3037		result = osst_write_filemark(STp, aSRpnt);
3038		if (result < 0) goto out;
3039
3040		if (STps->drv_file >= 0)
3041			STps->drv_file++ ;
3042		STps->drv_block = 0;
3043	}
3044	result = osst_write_eod(STp, aSRpnt);
3045	osst_write_header(STp, aSRpnt, leave_at_EOT);
3046
3047	STps->eof = ST_FM;
3048out:
3049	return result;
3050}
3051
3052/* osst versions of st functions - augmented and stripped to suit OnStream only */
3053
3054/* Flush the write buffer (never need to write if variable blocksize). */
3055static int osst_flush_write_buffer(struct osst_tape *STp, struct osst_request ** aSRpnt)
3056{
3057	int			offset, transfer, blks = 0;
3058	int			result = 0;
3059	unsigned char		cmd[MAX_COMMAND_SIZE];
3060	struct osst_request   * SRpnt = *aSRpnt;
3061	struct st_partstat    * STps;
3062	char		      * name = tape_name(STp);
3063
3064	if ((STp->buffer)->writing) {
3065		if (SRpnt == (STp->buffer)->last_SRpnt)
3066#if DEBUG
3067			{ printk(OSST_DEB_MSG
3068	 "%s:D: aSRpnt points to osst_request that write_behind_check will release -- cleared\n", name);
3069#endif
3070			*aSRpnt = SRpnt = NULL;
3071#if DEBUG
3072			} else if (SRpnt)
3073				printk(OSST_DEB_MSG
3074	 "%s:D: aSRpnt does not point to osst_request that write_behind_check will release -- strange\n", name);
3075#endif	
3076		osst_write_behind_check(STp);
3077		if ((STp->buffer)->syscall_result) {
3078#if DEBUG
3079			if (debugging)
3080				printk(OSST_DEB_MSG "%s:D: Async write error (flush) %x.\n",
3081				       name, (STp->buffer)->midlevel_result);
3082#endif
3083			if ((STp->buffer)->midlevel_result == INT_MAX)
3084				return (-ENOSPC);
3085			return (-EIO);
3086		}
3087	}
3088
3089	result = 0;
3090	if (STp->dirty == 1) {
3091
3092		STp->write_count++;
3093		STps     = &(STp->ps[STp->partition]);
3094		STps->rw = ST_WRITING;
3095		offset   = STp->buffer->buffer_bytes;
3096		blks     = (offset + STp->block_size - 1) / STp->block_size;
3097		transfer = OS_FRAME_SIZE;
3098		
3099		if (offset < OS_DATA_SIZE)
3100			osst_zero_buffer_tail(STp->buffer);
3101
3102		if (STp->poll)
3103			if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, -50, 120))
3104				result = osst_recover_wait_frame(STp, aSRpnt, 1);
3105
3106		memset(cmd, 0, MAX_COMMAND_SIZE);
3107		cmd[0] = WRITE_6;
3108		cmd[1] = 1;
3109		cmd[4] = 1;
3110
3111		switch	(STp->write_type) {
3112		   case OS_WRITE_DATA:
3113#if DEBUG
3114   			if (debugging)
3115				printk(OSST_DEB_MSG "%s:D: Writing %d blocks to frame %d, lblks %d-%d\n",
3116					name, blks, STp->frame_seq_number, 
3117					STp->logical_blk_num - blks, STp->logical_blk_num - 1);
3118#endif
3119			osst_init_aux(STp, OS_FRAME_TYPE_DATA, STp->frame_seq_number++,
3120				      STp->logical_blk_num - blks, STp->block_size, blks);
3121			break;
3122		   case OS_WRITE_EOD:
3123			osst_init_aux(STp, OS_FRAME_TYPE_EOD, STp->frame_seq_number++,
3124				      STp->logical_blk_num, 0, 0);
3125			break;
3126		   case OS_WRITE_NEW_MARK:
3127			osst_init_aux(STp, OS_FRAME_TYPE_MARKER, STp->frame_seq_number++,
3128				      STp->logical_blk_num++, 0, blks=1);
3129			break;
3130		   case OS_WRITE_HEADER:
3131			osst_init_aux(STp, OS_FRAME_TYPE_HEADER, 0, 0, 0, blks=0);
3132			break;
3133		default: /* probably FILLER */
3134			osst_init_aux(STp, OS_FRAME_TYPE_FILL, 0, 0, 0, 0);
3135		}
3136#if DEBUG
3137		if (debugging)
3138			printk(OSST_DEB_MSG "%s:D: Flushing %d bytes, Transferring %d bytes in %d lblocks.\n",
3139			  			 name, offset, transfer, blks);
3140#endif
3141
3142		SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
3143					      STp->timeout, MAX_RETRIES, 1);
3144		*aSRpnt = SRpnt;
3145		if (!SRpnt)
3146			return (-EBUSY);
3147
3148		if ((STp->buffer)->syscall_result != 0) {
3149#if DEBUG
3150			printk(OSST_DEB_MSG
3151				"%s:D: write sense [0]=0x%02x [2]=%02x [12]=%02x [13]=%02x\n",
3152				name, SRpnt->sense[0], SRpnt->sense[2],
3153				SRpnt->sense[12], SRpnt->sense[13]);
3154#endif
3155			if ((SRpnt->sense[0] & 0x70) == 0x70 &&
3156			    (SRpnt->sense[2] & 0x40) && /* FIXME - SC-30 drive doesn't assert EOM bit */
3157			    (SRpnt->sense[2] & 0x0f) == NO_SENSE) {
3158				STp->dirty = 0;
3159				(STp->buffer)->buffer_bytes = 0;
3160				result = (-ENOSPC);
3161			}
3162			else {
3163				if (osst_write_error_recovery(STp, aSRpnt, 1)) {
3164					printk(KERN_ERR "%s:E: Error on flush write.\n", name);
3165					result = (-EIO);
3166				}
3167			}
3168			STps->drv_block = (-1);		/* FIXME - even if write recovery succeeds? */
3169		}
3170		else {
3171			STp->first_frame_position++;
3172			STp->dirty = 0;
3173			(STp->buffer)->buffer_bytes = 0;
3174		}
3175	}
3176#if DEBUG
3177	printk(OSST_DEB_MSG "%s:D: Exit flush write buffer with code %d\n", name, result);
3178#endif
3179	return result;
3180}
3181
3182
3183/* Flush the tape buffer. The tape will be positioned correctly unless
3184   seek_next is true. */
3185static int osst_flush_buffer(struct osst_tape * STp, struct osst_request ** aSRpnt, int seek_next)
3186{
3187	struct st_partstat * STps;
3188	int    backspace = 0, result = 0;
3189#if DEBUG
3190	char * name = tape_name(STp);
3191#endif
3192
3193	/*
3194	 * If there was a bus reset, block further access
3195	 * to this device.
3196	 */
3197	if( STp->pos_unknown)
3198		return (-EIO);
3199
3200	if (STp->ready != ST_READY)
3201		return 0;
3202
3203	STps = &(STp->ps[STp->partition]);
3204	if (STps->rw == ST_WRITING || STp->dirty) {	/* Writing */
3205		STp->write_type = OS_WRITE_DATA;
3206		return osst_flush_write_buffer(STp, aSRpnt);
3207	}
3208	if (STp->block_size == 0)
3209		return 0;
3210
3211#if DEBUG
3212	printk(OSST_DEB_MSG "%s:D: Reached flush (read) buffer\n", name);
3213#endif
3214
3215	if (!STp->can_bsr) {
3216		backspace = ((STp->buffer)->buffer_bytes + (STp->buffer)->read_pointer) / STp->block_size -
3217			    ((STp->buffer)->read_pointer + STp->block_size - 1        ) / STp->block_size ;
3218		(STp->buffer)->buffer_bytes = 0;
3219		(STp->buffer)->read_pointer = 0;
3220		STp->frame_in_buffer = 0;		/* FIXME is this relevant w. OSST? */
3221	}
3222
3223	if (!seek_next) {
3224		if (STps->eof == ST_FM_HIT) {
3225			result = cross_eof(STp, aSRpnt, 0); /* Back over the EOF hit */
3226			if (!result)
3227				STps->eof = ST_NOEOF;
3228			else {
3229				if (STps->drv_file >= 0)
3230					STps->drv_file++;
3231				STps->drv_block = 0;
3232			}
3233		}
3234		if (!result && backspace > 0)	/* TODO -- design and run a test case for this */
3235			result = osst_seek_logical_blk(STp, aSRpnt, STp->logical_blk_num - backspace);
3236	}
3237	else if (STps->eof == ST_FM_HIT) {
3238		if (STps->drv_file >= 0)
3239			STps->drv_file++;
3240		STps->drv_block = 0;
3241		STps->eof = ST_NOEOF;
3242	}
3243
3244	return result;
3245}
3246
3247static int osst_write_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int synchronous)
3248{
3249	unsigned char		cmd[MAX_COMMAND_SIZE];
3250	struct osst_request   * SRpnt;
3251	int			blks;
3252#if DEBUG
3253	char		      * name = tape_name(STp);
3254#endif
3255
3256	if ((!STp-> raw) && (STp->first_frame_position == 0xbae)) { /* _must_ preserve buffer! */
3257#if DEBUG
3258		printk(OSST_DEB_MSG "%s:D: Reaching config partition.\n", name);
3259#endif
3260		if (osst_flush_drive_buffer(STp, aSRpnt) < 0) {
3261			return (-EIO);
3262		}
3263		/* error recovery may have bumped us past the header partition */
3264		if (osst_get_frame_position(STp, aSRpnt) < 0xbb8) {
3265#if DEBUG
3266			printk(OSST_DEB_MSG "%s:D: Skipping over config partition.\n", name);
3267#endif
3268		osst_position_tape_and_confirm(STp, aSRpnt, 0xbb8);
3269		}
3270	}
3271
3272	if (STp->poll)
3273		if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, -48, 120))
3274			if (osst_recover_wait_frame(STp, aSRpnt, 1))
3275				return (-EIO);
3276
3277//	osst_build_stats(STp, &SRpnt);
3278
3279	STp->ps[STp->partition].rw = ST_WRITING;
3280	STp->write_type            = OS_WRITE_DATA;
3281			
3282	memset(cmd, 0, MAX_COMMAND_SIZE);
3283	cmd[0]   = WRITE_6;
3284	cmd[1]   = 1;
3285	cmd[4]   = 1;						/* one frame at a time... */
3286	blks     = STp->buffer->buffer_bytes / STp->block_size;
3287#if DEBUG
3288	if (debugging)
3289		printk(OSST_DEB_MSG "%s:D: Writing %d blocks to frame %d, lblks %d-%d\n", name, blks, 
3290			STp->frame_seq_number, STp->logical_blk_num - blks, STp->logical_blk_num - 1);
3291#endif
3292	osst_init_aux(STp, OS_FRAME_TYPE_DATA, STp->frame_seq_number++,
3293		      STp->logical_blk_num - blks, STp->block_size, blks);
3294
3295#if DEBUG
3296	if (!synchronous)
3297		STp->write_pending = 1;
3298#endif
3299	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE, STp->timeout,
3300									MAX_RETRIES, synchronous);
3301	if (!SRpnt)
3302		return (-EBUSY);
3303	*aSRpnt = SRpnt;
3304
3305	if (synchronous) {
3306		if (STp->buffer->syscall_result != 0) {
3307#if DEBUG
3308			if (debugging)
3309				printk(OSST_DEB_MSG "%s:D: Error on write:\n", name);
3310#endif
3311			if ((SRpnt->sense[0] & 0x70) == 0x70 &&
3312			    (SRpnt->sense[2] & 0x40)) {
3313				if ((SRpnt->sense[2] & 0x0f) == VOLUME_OVERFLOW)
3314					return (-ENOSPC);
3315			}
3316			else {
3317				if (osst_write_error_recovery(STp, aSRpnt, 1))
3318					return (-EIO);
3319			}
3320		}
3321		else
3322			STp->first_frame_position++;
3323	}
3324
3325	STp->write_count++;
3326
3327	return 0;
3328}
3329
3330/* Lock or unlock the drive door. Don't use when struct osst_request allocated. */
3331static int do_door_lock(struct osst_tape * STp, int do_lock)
3332{
3333	int retval;
3334
 
3335#if DEBUG
3336	printk(OSST_DEB_MSG "%s:D: %socking drive door.\n", tape_name(STp), do_lock ? "L" : "Unl");
3337#endif
3338
3339	retval = scsi_set_medium_removal(STp->device,
3340			do_lock ? SCSI_REMOVAL_PREVENT : SCSI_REMOVAL_ALLOW);
3341	if (!retval)
3342		STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
3343	else
 
3344		STp->door_locked = ST_LOCK_FAILS;
 
3345	return retval;
3346}
3347
3348/* Set the internal state after reset */
3349static void reset_state(struct osst_tape *STp)
3350{
3351	int i;
3352	struct st_partstat *STps;
3353
3354	STp->pos_unknown = 0;
3355	for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3356		STps = &(STp->ps[i]);
3357		STps->rw = ST_IDLE;
3358		STps->eof = ST_NOEOF;
3359		STps->at_sm = 0;
3360		STps->last_block_valid = 0;
3361		STps->drv_block = -1;
3362		STps->drv_file = -1;
3363	}
3364}
3365				
3366
3367/* Entry points to osst */
3368
3369/* Write command */
3370static ssize_t osst_write(struct file * filp, const char __user * buf, size_t count, loff_t *ppos)
3371{
3372	ssize_t		      total, retval = 0;
3373	ssize_t		      i, do_count, blks, transfer;
3374	int		      write_threshold;
3375	int		      doing_write = 0;
3376	const char   __user * b_point;
3377	struct osst_request * SRpnt = NULL;
3378	struct st_modedef   * STm;
3379	struct st_partstat  * STps;
3380	struct osst_tape    * STp  = filp->private_data;
3381	char		    * name = tape_name(STp);
3382
3383
3384	if (mutex_lock_interruptible(&STp->lock))
3385		return (-ERESTARTSYS);
3386
3387	/*
3388	 * If we are in the middle of error recovery, don't let anyone
3389	 * else try and use this device.  Also, if error recovery fails, it
3390	 * may try and take the device offline, in which case all further
3391	 * access to the device is prohibited.
3392	 */
3393	if( !scsi_block_when_processing_errors(STp->device) ) {
3394		retval = (-ENXIO);
3395		goto out;
3396	}
3397	
3398	if (STp->ready != ST_READY) {
3399		if (STp->ready == ST_NO_TAPE)
3400			retval = (-ENOMEDIUM);
3401		else
3402			retval = (-EIO);
3403		goto out;
3404	}
3405	STm = &(STp->modes[STp->current_mode]);
3406	if (!STm->defined) {
3407		retval = (-ENXIO);
3408		goto out;
3409	}
3410	if (count == 0)
3411		goto out;
3412
3413	/*
3414	 * If there was a bus reset, block further access
3415	 * to this device.
3416	 */
3417	if (STp->pos_unknown) {
3418		retval = (-EIO);
3419		goto out;
3420	}
3421
3422#if DEBUG
3423	if (!STp->in_use) {
3424		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
3425		retval = (-EIO);
3426		goto out;
3427	}
3428#endif
3429
3430	if (STp->write_prot) {
3431		retval = (-EACCES);
3432		goto out;
3433	}
3434
3435	/* Write must be integral number of blocks */
3436	if (STp->block_size != 0 && (count % STp->block_size) != 0) {
3437		printk(KERN_ERR "%s:E: Write (%zd bytes) not multiple of tape block size (%d%c).\n",
3438				       name, count, STp->block_size<1024?
3439				       STp->block_size:STp->block_size/1024, STp->block_size<1024?'b':'k');
3440		retval = (-EINVAL);
3441		goto out;
3442	}
3443
3444	if (STp->first_frame_position >= STp->capacity - OSST_EOM_RESERVE) {
3445		printk(KERN_ERR "%s:E: Write truncated at EOM early warning (frame %d).\n",
3446				       name, STp->first_frame_position);
3447		retval = (-ENOSPC);
3448		goto out;
3449	}
3450
3451	if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED && !do_door_lock(STp, 1))
3452		STp->door_locked = ST_LOCKED_AUTO;
3453
3454	STps = &(STp->ps[STp->partition]);
3455
3456	if (STps->rw == ST_READING) {
3457#if DEBUG
3458		printk(OSST_DEB_MSG "%s:D: Switching from read to write at file %d, block %d\n", name, 
3459					STps->drv_file, STps->drv_block);
3460#endif
3461		retval = osst_flush_buffer(STp, &SRpnt, 0);
3462		if (retval)
3463			goto out;
3464		STps->rw = ST_IDLE;
3465	}
3466	if (STps->rw != ST_WRITING) {
3467		/* Are we totally rewriting this tape? */
3468		if (!STp->header_ok ||
3469		    (STp->first_frame_position == STp->first_data_ppos && STps->drv_block < 0) ||
3470		    (STps->drv_file == 0 && STps->drv_block == 0)) {
3471			STp->wrt_pass_cntr++;
3472#if DEBUG
3473			printk(OSST_DEB_MSG "%s:D: Allocating next write pass counter: %d\n",
3474						  name, STp->wrt_pass_cntr);
3475#endif
3476			osst_reset_header(STp, &SRpnt);
3477			STps->drv_file = STps->drv_block = 0;
3478		}
3479		/* Do we know where we'll be writing on the tape? */
3480		else {
3481			if ((STp->fast_open && osst_verify_position(STp, &SRpnt)) ||
3482			  		STps->drv_file < 0 || STps->drv_block < 0) {
3483				if (STp->first_frame_position == STp->eod_frame_ppos) {	/* at EOD */
3484			  		STps->drv_file = STp->filemark_cnt;
3485			  		STps->drv_block = 0;
3486				}
3487				else {
3488					/* We have no idea where the tape is positioned - give up */
3489#if DEBUG
3490					printk(OSST_DEB_MSG
3491						"%s:D: Cannot write at indeterminate position.\n", name);
3492#endif
3493					retval = (-EIO);
3494					goto out;
3495				}
3496      			}	  
3497			if ((STps->drv_file + STps->drv_block) > 0 && STps->drv_file < STp->filemark_cnt) {
3498				STp->filemark_cnt = STps->drv_file;
3499				STp->last_mark_ppos =
3500				       	ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[STp->filemark_cnt-1]);
3501				printk(KERN_WARNING
3502					"%s:W: Overwriting file %d with old write pass counter %d\n",
3503						name, STps->drv_file, STp->wrt_pass_cntr);
3504				printk(KERN_WARNING
3505					"%s:W: may lead to stale data being accepted on reading back!\n",
3506						name);
3507#if DEBUG
3508				printk(OSST_DEB_MSG
3509				  "%s:D: resetting filemark count to %d and last mark ppos,lbn to %d,%d\n",
3510					name, STp->filemark_cnt, STp->last_mark_ppos, STp->last_mark_lbn);
3511#endif
3512			}
3513		}
3514		STp->fast_open = 0;
3515	}
3516	if (!STp->header_ok) {
3517#if DEBUG
3518		printk(OSST_DEB_MSG "%s:D: Write cannot proceed without valid headers\n", name);
3519#endif
3520		retval = (-EIO);
3521		goto out;
3522	}
3523
3524	if ((STp->buffer)->writing) {
3525if (SRpnt) printk(KERN_ERR "%s:A: Not supposed to have SRpnt at line %d\n", name, __LINE__);
3526		osst_write_behind_check(STp);
3527		if ((STp->buffer)->syscall_result) {
3528#if DEBUG
3529		if (debugging)
3530			printk(OSST_DEB_MSG "%s:D: Async write error (write) %x.\n", name,
3531						 (STp->buffer)->midlevel_result);
3532#endif
3533		if ((STp->buffer)->midlevel_result == INT_MAX)
3534			STps->eof = ST_EOM_OK;
3535		else
3536			STps->eof = ST_EOM_ERROR;
3537		}
3538	}
3539	if (STps->eof == ST_EOM_OK) {
3540		retval = (-ENOSPC);
3541		goto out;
3542	}
3543	else if (STps->eof == ST_EOM_ERROR) {
3544		retval = (-EIO);
3545		goto out;
3546	}
3547
3548	/* Check the buffer readability in cases where copy_user might catch
3549		 the problems after some tape movement. */
3550	if ((copy_from_user(&i, buf, 1) != 0 ||
3551	     copy_from_user(&i, buf + count - 1, 1) != 0)) {
3552		retval = (-EFAULT);
3553		goto out;
3554	}
3555
3556	if (!STm->do_buffer_writes) {
3557		write_threshold = 1;
3558	}
3559	else
3560		write_threshold = (STp->buffer)->buffer_blocks * STp->block_size;
3561	if (!STm->do_async_writes)
3562		write_threshold--;
3563
3564	total = count;
3565#if DEBUG
3566	if (debugging)
3567		printk(OSST_DEB_MSG "%s:D: Writing %d bytes to file %d block %d lblk %d fseq %d fppos %d\n",
3568				name, (int) count, STps->drv_file, STps->drv_block,
3569				STp->logical_blk_num, STp->frame_seq_number, STp->first_frame_position);
3570#endif
3571	b_point = buf;
3572	while ((STp->buffer)->buffer_bytes + count > write_threshold)
3573	{
3574		doing_write = 1;
3575		do_count = (STp->buffer)->buffer_blocks * STp->block_size -
3576			   (STp->buffer)->buffer_bytes;
3577		if (do_count > count)
3578			do_count = count;
3579
3580		i = append_to_buffer(b_point, STp->buffer, do_count);
3581		if (i) {
3582			retval = i;
3583			goto out;
3584		}
3585
3586		blks = do_count / STp->block_size;
3587		STp->logical_blk_num += blks;  /* logical_blk_num is incremented as data is moved from user */
3588  
3589		i = osst_write_frame(STp, &SRpnt, 1);
3590
3591		if (i == (-ENOSPC)) {
3592			transfer = STp->buffer->writing;	/* FIXME -- check this logic */
3593			if (transfer <= do_count) {
3594				*ppos += do_count - transfer;
3595				count -= do_count - transfer;
3596				if (STps->drv_block >= 0) {
3597					STps->drv_block += (do_count - transfer) / STp->block_size;
3598				}
3599				STps->eof = ST_EOM_OK;
3600				retval = (-ENOSPC);		/* EOM within current request */
3601#if DEBUG
3602				if (debugging)
3603				      printk(OSST_DEB_MSG "%s:D: EOM with %d bytes unwritten.\n",
3604							     name, (int) transfer);
3605#endif
3606			}
3607			else {
3608				STps->eof = ST_EOM_ERROR;
3609				STps->drv_block = (-1);		/* Too cautious? */
3610				retval = (-EIO);		/* EOM for old data */
3611#if DEBUG
3612				if (debugging)
3613				      printk(OSST_DEB_MSG "%s:D: EOM with lost data.\n", name);
3614#endif
3615			}
3616		}
3617		else
3618			retval = i;
3619			
3620		if (retval < 0) {
3621			if (SRpnt != NULL) {
3622				osst_release_request(SRpnt);
3623				SRpnt = NULL;
3624			}
3625			STp->buffer->buffer_bytes = 0;
3626			STp->dirty = 0;
3627			if (count < total)
3628				retval = total - count;
3629			goto out;
3630		}
3631
3632		*ppos += do_count;
3633		b_point += do_count;
3634		count -= do_count;
3635		if (STps->drv_block >= 0) {
3636			STps->drv_block += blks;
3637		}
3638		STp->buffer->buffer_bytes = 0;
3639		STp->dirty = 0;
3640	}  /* end while write threshold exceeded */
3641
3642	if (count != 0) {
3643		STp->dirty = 1;
3644		i = append_to_buffer(b_point, STp->buffer, count);
3645		if (i) {
3646			retval = i;
3647			goto out;
3648		}
3649		blks = count / STp->block_size;
3650		STp->logical_blk_num += blks;
3651		if (STps->drv_block >= 0) {
3652			STps->drv_block += blks;
3653		}
3654		*ppos += count;
3655		count = 0;
3656	}
3657
3658	if (doing_write && (STp->buffer)->syscall_result != 0) {
3659		retval = (STp->buffer)->syscall_result;
3660		goto out;
3661	}
3662
3663	if (STm->do_async_writes && ((STp->buffer)->buffer_bytes >= STp->write_threshold)) { 
3664		/* Schedule an asynchronous write */
3665		(STp->buffer)->writing = ((STp->buffer)->buffer_bytes /
3666					   STp->block_size) * STp->block_size;
3667		STp->dirty = !((STp->buffer)->writing ==
3668				          (STp->buffer)->buffer_bytes);
3669
3670		i = osst_write_frame(STp, &SRpnt, 0);
3671		if (i < 0) {
3672			retval = (-EIO);
3673			goto out;
3674		}
3675		SRpnt = NULL;			/* Prevent releasing this request! */
3676	}
3677	STps->at_sm &= (total == 0);
3678	if (total > 0)
3679		STps->eof = ST_NOEOF;
3680
3681	retval = total;
3682
3683out:
3684	if (SRpnt != NULL) osst_release_request(SRpnt);
3685
3686	mutex_unlock(&STp->lock);
3687
3688	return retval;
3689}
3690
3691
3692/* Read command */
3693static ssize_t osst_read(struct file * filp, char __user * buf, size_t count, loff_t *ppos)
3694{
3695	ssize_t		      total, retval = 0;
3696	ssize_t		      i, transfer;
3697	int		      special;
3698	struct st_modedef   * STm;
3699	struct st_partstat  * STps;
3700	struct osst_request * SRpnt = NULL;
3701	struct osst_tape    * STp   = filp->private_data;
3702	char		    * name  = tape_name(STp);
3703
3704
3705	if (mutex_lock_interruptible(&STp->lock))
3706		return (-ERESTARTSYS);
3707
3708	/*
3709	 * If we are in the middle of error recovery, don't let anyone
3710	 * else try and use this device.  Also, if error recovery fails, it
3711	 * may try and take the device offline, in which case all further
3712	 * access to the device is prohibited.
3713	 */
3714	if( !scsi_block_when_processing_errors(STp->device) ) {
3715		retval = (-ENXIO);
3716		goto out;
3717	}
3718	
3719	if (STp->ready != ST_READY) {
3720		if (STp->ready == ST_NO_TAPE)
3721			retval = (-ENOMEDIUM);
3722		else
3723			retval = (-EIO);
3724		goto out;
3725	}
3726	STm = &(STp->modes[STp->current_mode]);
3727	if (!STm->defined) {
3728		retval = (-ENXIO);
3729		goto out;
3730	}
3731#if DEBUG
3732	if (!STp->in_use) {
3733		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
3734		retval = (-EIO);
3735		goto out;
3736	}
3737#endif
3738	/* Must have initialized medium */
3739	if (!STp->header_ok) {
3740		retval = (-EIO);
3741		goto out;
3742	}
3743
3744	if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED && !do_door_lock(STp, 1))
3745		STp->door_locked = ST_LOCKED_AUTO;
3746
3747	STps = &(STp->ps[STp->partition]);
3748	if (STps->rw == ST_WRITING) {
3749		retval = osst_flush_buffer(STp, &SRpnt, 0);
3750		if (retval)
3751			goto out;
3752		STps->rw = ST_IDLE;
3753		/* FIXME -- this may leave the tape without EOD and up2date headers */
3754	}
3755
3756	if ((count % STp->block_size) != 0) {
3757		printk(KERN_WARNING
3758		    "%s:W: Read (%zd bytes) not multiple of tape block size (%d%c).\n", name, count,
3759		    STp->block_size<1024?STp->block_size:STp->block_size/1024, STp->block_size<1024?'b':'k');
3760	}
3761
3762#if DEBUG
3763	if (debugging && STps->eof != ST_NOEOF)
3764		printk(OSST_DEB_MSG "%s:D: EOF/EOM flag up (%d). Bytes %d\n", name,
3765				     STps->eof, (STp->buffer)->buffer_bytes);
3766#endif
3767	if ((STp->buffer)->buffer_bytes == 0 &&
3768	     STps->eof >= ST_EOD_1) {
3769		if (STps->eof < ST_EOD) {
3770			STps->eof += 1;
3771			retval = 0;
3772			goto out;
3773		}
3774		retval = (-EIO);  /* EOM or Blank Check */
3775		goto out;
3776	}
3777
3778	/* Check the buffer writability before any tape movement. Don't alter
3779		 buffer data. */
3780	if (copy_from_user(&i, buf, 1)             != 0 ||
3781	    copy_to_user  (buf, &i, 1)             != 0 ||
3782	    copy_from_user(&i, buf + count - 1, 1) != 0 ||
3783	    copy_to_user  (buf + count - 1, &i, 1) != 0) {
3784		retval = (-EFAULT);
3785		goto out;
3786	}
3787
3788	/* Loop until enough data in buffer or a special condition found */
3789	for (total = 0, special = 0; total < count - STp->block_size + 1 && !special; ) {
3790
3791		/* Get new data if the buffer is empty */
3792		if ((STp->buffer)->buffer_bytes == 0) {
3793			if (STps->eof == ST_FM_HIT)
3794				break;
3795			special = osst_get_logical_frame(STp, &SRpnt, STp->frame_seq_number, 0);
3796			if (special < 0) { 			/* No need to continue read */
3797				STp->frame_in_buffer = 0;
3798				retval = special;
3799				goto out;
3800			}
3801		}
3802
3803		/* Move the data from driver buffer to user buffer */
3804		if ((STp->buffer)->buffer_bytes > 0) {
3805#if DEBUG
3806			if (debugging && STps->eof != ST_NOEOF)
3807			    printk(OSST_DEB_MSG "%s:D: EOF up (%d). Left %d, needed %d.\n", name,
3808						 STps->eof, (STp->buffer)->buffer_bytes, (int) (count - total));
3809#endif
3810		       	/* force multiple of block size, note block_size may have been adjusted */
3811			transfer = (((STp->buffer)->buffer_bytes < count - total ?
3812				     (STp->buffer)->buffer_bytes : count - total)/
3813					STp->block_size) * STp->block_size;
3814
3815			if (transfer == 0) {
3816				printk(KERN_WARNING
3817				  "%s:W: Nothing can be transferred, requested %zd, tape block size (%d%c).\n",
3818			   		name, count, STp->block_size < 1024?
3819					STp->block_size:STp->block_size/1024,
3820				       	STp->block_size<1024?'b':'k');
3821				break;
3822			}
3823			i = from_buffer(STp->buffer, buf, transfer);
3824			if (i)  {
3825				retval = i;
3826				goto out;
3827			}
3828			STp->logical_blk_num += transfer / STp->block_size;
3829			STps->drv_block      += transfer / STp->block_size;
3830			*ppos          += transfer;
3831			buf                  += transfer;
3832			total                += transfer;
3833		}
3834 
3835		if ((STp->buffer)->buffer_bytes == 0) {
3836#if DEBUG
3837			if (debugging)
3838				printk(OSST_DEB_MSG "%s:D: Finished with frame %d\n",
3839					       	name, STp->frame_seq_number);
3840#endif
3841			STp->frame_in_buffer = 0;
3842			STp->frame_seq_number++;              /* frame to look for next time */
3843		}
3844	} /* for (total = 0, special = 0; total < count && !special; ) */
3845
3846	/* Change the eof state if no data from tape or buffer */
3847	if (total == 0) {
3848		if (STps->eof == ST_FM_HIT) {
3849			STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD_2:ST_FM;
3850			STps->drv_block = 0;
3851			if (STps->drv_file >= 0)
3852				STps->drv_file++;
3853		}
3854		else if (STps->eof == ST_EOD_1) {
3855			STps->eof = ST_EOD_2;
3856			if (STps->drv_block > 0 && STps->drv_file >= 0)
3857				STps->drv_file++;
3858			STps->drv_block = 0;
3859		}
3860		else if (STps->eof == ST_EOD_2)
3861			STps->eof = ST_EOD;
3862	}
3863	else if (STps->eof == ST_FM)
3864		STps->eof = ST_NOEOF;
3865
3866	retval = total;
3867
3868out:
3869	if (SRpnt != NULL) osst_release_request(SRpnt);
3870
3871	mutex_unlock(&STp->lock);
3872
3873	return retval;
3874}
3875
3876
3877/* Set the driver options */
3878static void osst_log_options(struct osst_tape *STp, struct st_modedef *STm, char *name)
3879{
3880  printk(KERN_INFO
3881"%s:I: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
3882	 name, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
3883	 STm->do_read_ahead);
3884  printk(KERN_INFO
3885"%s:I:    can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
3886	 name, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
3887  printk(KERN_INFO
3888"%s:I:    defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
3889	 name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
3890	 STp->scsi2_logical);
3891  printk(KERN_INFO
3892"%s:I:    sysv: %d\n", name, STm->sysv);
3893#if DEBUG
3894  printk(KERN_INFO
3895	 "%s:D:    debugging: %d\n",
3896	 name, debugging);
3897#endif
3898}
3899
3900
3901static int osst_set_options(struct osst_tape *STp, long options)
3902{
3903	int		    value;
3904	long		    code;
3905	struct st_modedef * STm;
3906	char		  * name = tape_name(STp);
3907
3908	STm = &(STp->modes[STp->current_mode]);
3909	if (!STm->defined) {
3910		memcpy(STm, &(STp->modes[0]), sizeof(*STm));
3911		modes_defined = 1;
3912#if DEBUG
3913		if (debugging)
3914			printk(OSST_DEB_MSG "%s:D: Initialized mode %d definition from mode 0\n",
3915					     name, STp->current_mode);
3916#endif
3917	}
3918
3919	code = options & MT_ST_OPTIONS;
3920	if (code == MT_ST_BOOLEANS) {
3921		STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
3922		STm->do_async_writes  = (options & MT_ST_ASYNC_WRITES) != 0;
3923		STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
3924		STm->do_read_ahead    = (options & MT_ST_READ_AHEAD) != 0;
3925		STp->two_fm	      = (options & MT_ST_TWO_FM) != 0;
3926		STp->fast_mteom	      = (options & MT_ST_FAST_MTEOM) != 0;
3927		STp->do_auto_lock     = (options & MT_ST_AUTO_LOCK) != 0;
3928		STp->can_bsr          = (options & MT_ST_CAN_BSR) != 0;
3929		STp->omit_blklims     = (options & MT_ST_NO_BLKLIMS) != 0;
3930		if ((STp->device)->scsi_level >= SCSI_2)
3931			STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
3932		STp->scsi2_logical    = (options & MT_ST_SCSI2LOGICAL) != 0;
3933		STm->sysv	      = (options & MT_ST_SYSV) != 0;
3934#if DEBUG
3935		debugging = (options & MT_ST_DEBUGGING) != 0;
3936#endif
3937		osst_log_options(STp, STm, name);
3938	}
3939	else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
3940		value = (code == MT_ST_SETBOOLEANS);
3941		if ((options & MT_ST_BUFFER_WRITES) != 0)
3942			STm->do_buffer_writes = value;
3943		if ((options & MT_ST_ASYNC_WRITES) != 0)
3944			STm->do_async_writes = value;
3945		if ((options & MT_ST_DEF_WRITES) != 0)
3946			STm->defaults_for_writes = value;
3947		if ((options & MT_ST_READ_AHEAD) != 0)
3948			STm->do_read_ahead = value;
3949		if ((options & MT_ST_TWO_FM) != 0)
3950			STp->two_fm = value;
3951		if ((options & MT_ST_FAST_MTEOM) != 0)
3952			STp->fast_mteom = value;
3953		if ((options & MT_ST_AUTO_LOCK) != 0)
3954			STp->do_auto_lock = value;
3955		if ((options & MT_ST_CAN_BSR) != 0)
3956			STp->can_bsr = value;
3957		if ((options & MT_ST_NO_BLKLIMS) != 0)
3958			STp->omit_blklims = value;
3959		if ((STp->device)->scsi_level >= SCSI_2 &&
3960		    (options & MT_ST_CAN_PARTITIONS) != 0)
3961			STp->can_partitions = value;
3962		if ((options & MT_ST_SCSI2LOGICAL) != 0)
3963			STp->scsi2_logical = value;
3964		if ((options & MT_ST_SYSV) != 0)
3965			STm->sysv = value;
3966#if DEBUG
3967		if ((options & MT_ST_DEBUGGING) != 0)
3968			debugging = value;
3969#endif
3970		osst_log_options(STp, STm, name);
3971	}
3972	else if (code == MT_ST_WRITE_THRESHOLD) {
3973		value = (options & ~MT_ST_OPTIONS) * ST_KILOBYTE;
3974		if (value < 1 || value > osst_buffer_size) {
3975			printk(KERN_WARNING "%s:W: Write threshold %d too small or too large.\n",
3976					     name, value);
3977			return (-EIO);
3978		}
3979		STp->write_threshold = value;
3980		printk(KERN_INFO "%s:I: Write threshold set to %d bytes.\n",
3981				  name, value);
3982	}
3983	else if (code == MT_ST_DEF_BLKSIZE) {
3984		value = (options & ~MT_ST_OPTIONS);
3985		if (value == ~MT_ST_OPTIONS) {
3986			STm->default_blksize = (-1);
3987			printk(KERN_INFO "%s:I: Default block size disabled.\n", name);
3988		}
3989		else {
3990			if (value < 512 || value > OS_DATA_SIZE || OS_DATA_SIZE % value) {
3991				printk(KERN_WARNING "%s:W: Default block size cannot be set to %d.\n",
3992							 name, value);
3993				return (-EINVAL);
3994			}
3995			STm->default_blksize = value;
3996			printk(KERN_INFO "%s:I: Default block size set to %d bytes.\n",
3997					  name, STm->default_blksize);
3998		}
3999	}
4000	else if (code == MT_ST_TIMEOUTS) {
4001		value = (options & ~MT_ST_OPTIONS);
4002		if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
4003			STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
4004			printk(KERN_INFO "%s:I: Long timeout set to %d seconds.\n", name,
4005					     (value & ~MT_ST_SET_LONG_TIMEOUT));
4006		}
4007		else {
4008			STp->timeout = value * HZ;
4009			printk(KERN_INFO "%s:I: Normal timeout set to %d seconds.\n", name, value);
4010		}
4011	}
4012	else if (code == MT_ST_DEF_OPTIONS) {
4013		code = (options & ~MT_ST_CLEAR_DEFAULT);
4014		value = (options & MT_ST_CLEAR_DEFAULT);
4015		if (code == MT_ST_DEF_DENSITY) {
4016			if (value == MT_ST_CLEAR_DEFAULT) {
4017				STm->default_density = (-1);
4018				printk(KERN_INFO "%s:I: Density default disabled.\n", name);
4019			}
4020			else {
4021				STm->default_density = value & 0xff;
4022				printk(KERN_INFO "%s:I: Density default set to %x\n",
4023						  name, STm->default_density);
4024			}
4025		}
4026		else if (code == MT_ST_DEF_DRVBUFFER) {
4027			if (value == MT_ST_CLEAR_DEFAULT) {
4028				STp->default_drvbuffer = 0xff;
4029				printk(KERN_INFO "%s:I: Drive buffer default disabled.\n", name);
4030			}
4031			else {
4032				STp->default_drvbuffer = value & 7;
4033				printk(KERN_INFO "%s:I: Drive buffer default set to %x\n",
4034						  name, STp->default_drvbuffer);
4035			}
4036		}
4037		else if (code == MT_ST_DEF_COMPRESSION) {
4038			if (value == MT_ST_CLEAR_DEFAULT) {
4039				STm->default_compression = ST_DONT_TOUCH;
4040				printk(KERN_INFO "%s:I: Compression default disabled.\n", name);
4041			}
4042			else {
4043				STm->default_compression = (value & 1 ? ST_YES : ST_NO);
4044				printk(KERN_INFO "%s:I: Compression default set to %x\n",
4045						  name, (value & 1));
4046			}
4047		}
4048	}
4049	else
4050		return (-EIO);
4051
4052	return 0;
4053}
4054
4055
4056/* Internal ioctl function */
4057static int osst_int_ioctl(struct osst_tape * STp, struct osst_request ** aSRpnt,
4058			     unsigned int cmd_in, unsigned long arg)
4059{
4060	int			timeout;
4061	long			ltmp;
4062	int			i, ioctl_result;
4063	int			chg_eof = 1;
4064	unsigned char		cmd[MAX_COMMAND_SIZE];
4065	struct osst_request   * SRpnt = * aSRpnt;
4066	struct st_partstat    * STps;
4067	int			fileno, blkno, at_sm, frame_seq_numbr, logical_blk_num;
4068	int			datalen = 0, direction = DMA_NONE;
4069	char		      * name = tape_name(STp);
4070
4071	if (STp->ready != ST_READY && cmd_in != MTLOAD) {
4072		if (STp->ready == ST_NO_TAPE)
4073			return (-ENOMEDIUM);
4074		else
4075			return (-EIO);
4076	}
4077	timeout = STp->long_timeout;
4078	STps = &(STp->ps[STp->partition]);
4079	fileno = STps->drv_file;
4080	blkno = STps->drv_block;
4081	at_sm = STps->at_sm;
4082	frame_seq_numbr = STp->frame_seq_number;
4083	logical_blk_num = STp->logical_blk_num;
4084
4085	memset(cmd, 0, MAX_COMMAND_SIZE);
4086	switch (cmd_in) {
4087	 case MTFSFM:
4088		chg_eof = 0; /* Changed from the FSF after this */
4089	 case MTFSF:
4090		if (STp->raw)
4091		   return (-EIO);
4092		if (STp->linux_media)
4093		   ioctl_result = osst_space_over_filemarks_forward_fast(STp, &SRpnt, cmd_in, arg);
4094		else
4095		   ioctl_result = osst_space_over_filemarks_forward_slow(STp, &SRpnt, cmd_in, arg);
4096		if (fileno >= 0)
4097		   fileno += arg;
4098		blkno = 0;
4099		at_sm &= (arg == 0);
4100		goto os_bypass;
4101
4102	 case MTBSF:
4103		chg_eof = 0; /* Changed from the FSF after this */
4104	 case MTBSFM:
4105		if (STp->raw)
4106		   return (-EIO);
4107		ioctl_result = osst_space_over_filemarks_backward(STp, &SRpnt, cmd_in, arg);
4108		if (fileno >= 0)
4109		   fileno -= arg;
4110		blkno = (-1);  /* We can't know the block number */
4111		at_sm &= (arg == 0);
4112		goto os_bypass;
4113
4114	 case MTFSR:
4115	 case MTBSR:
4116#if DEBUG
4117		if (debugging)
4118		   printk(OSST_DEB_MSG "%s:D: Skipping %lu blocks %s from logical block %d\n",
4119				name, arg, cmd_in==MTFSR?"forward":"backward", logical_blk_num);
4120#endif
4121		if (cmd_in == MTFSR) {
4122		   logical_blk_num += arg;
4123		   if (blkno >= 0) blkno += arg;
4124		}
4125		else {
4126		   logical_blk_num -= arg;
4127		   if (blkno >= 0) blkno -= arg;
4128		}
4129		ioctl_result = osst_seek_logical_blk(STp, &SRpnt, logical_blk_num);
4130		fileno = STps->drv_file;
4131		blkno  = STps->drv_block;
4132		at_sm &= (arg == 0);
4133		goto os_bypass;
4134
4135	 case MTFSS:
4136		cmd[0] = SPACE;
4137		cmd[1] = 0x04; /* Space Setmarks */   /* FIXME -- OS can't do this? */
4138		cmd[2] = (arg >> 16);
4139		cmd[3] = (arg >> 8);
4140		cmd[4] = arg;
4141#if DEBUG
4142		if (debugging)
4143			printk(OSST_DEB_MSG "%s:D: Spacing tape forward %d setmarks.\n", name,
4144		cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
4145#endif
4146		if (arg != 0) {
4147			blkno = fileno = (-1);
4148			at_sm = 1;
4149		}
4150		break;
4151	 case MTBSS:
4152		cmd[0] = SPACE;
4153		cmd[1] = 0x04; /* Space Setmarks */   /* FIXME -- OS can't do this? */
4154		ltmp = (-arg);
4155		cmd[2] = (ltmp >> 16);
4156		cmd[3] = (ltmp >> 8);
4157		cmd[4] = ltmp;
4158#if DEBUG
4159		if (debugging) {
4160			if (cmd[2] & 0x80)
4161			   ltmp = 0xff000000;
4162			ltmp = ltmp | (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
4163			printk(OSST_DEB_MSG "%s:D: Spacing tape backward %ld setmarks.\n",
4164						name, (-ltmp));
4165		 }
4166#endif
4167		 if (arg != 0) {
4168			blkno = fileno = (-1);
4169			at_sm = 1;
4170		 }
4171		 break;
4172	 case MTWEOF:
4173		 if ((STps->rw == ST_WRITING || STp->dirty) && !STp->pos_unknown) {
4174			STp->write_type = OS_WRITE_DATA;
4175			ioctl_result = osst_flush_write_buffer(STp, &SRpnt);
4176		 } else
4177			ioctl_result = 0;
4178#if DEBUG
4179		 if (debugging) 
4180			   printk(OSST_DEB_MSG "%s:D: Writing %ld filemark(s).\n", name, arg);
4181#endif
4182		 for (i=0; i<arg; i++)
4183			ioctl_result |= osst_write_filemark(STp, &SRpnt);
4184		 if (fileno >= 0) fileno += arg;
4185		 if (blkno  >= 0) blkno   = 0;
4186		 goto os_bypass;
4187
4188	 case MTWSM:
4189		 if (STp->write_prot)
4190			return (-EACCES);
4191		 if (!STp->raw)
4192			return 0;
4193		 cmd[0] = WRITE_FILEMARKS;   /* FIXME -- need OS version */
4194		 if (cmd_in == MTWSM)
4195			 cmd[1] = 2;
4196		 cmd[2] = (arg >> 16);
4197		 cmd[3] = (arg >> 8);
4198		 cmd[4] = arg;
4199		 timeout = STp->timeout;
4200#if DEBUG
4201		 if (debugging) 
4202			   printk(OSST_DEB_MSG "%s:D: Writing %d setmark(s).\n", name,
4203				  cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
4204#endif
4205		 if (fileno >= 0)
4206			fileno += arg;
4207		 blkno = 0;
4208		 at_sm = (cmd_in == MTWSM);
4209		 break;
4210	 case MTOFFL:
4211	 case MTLOAD:
4212	 case MTUNLOAD:
4213	 case MTRETEN:
4214		 cmd[0] = START_STOP;
4215		 cmd[1] = 1;			/* Don't wait for completion */
4216		 if (cmd_in == MTLOAD) {
4217		     if (STp->ready == ST_NO_TAPE)
4218			 cmd[4] = 4;		/* open tray */
4219		      else
4220			 cmd[4] = 1;		/* load */
4221		 }
4222		 if (cmd_in == MTRETEN)
4223			 cmd[4] = 3;		/* retension then mount */
4224		 if (cmd_in == MTOFFL)
4225			 cmd[4] = 4;		/* rewind then eject */
4226		 timeout = STp->timeout;
4227#if DEBUG
4228		 if (debugging) {
4229			 switch (cmd_in) {
4230				 case MTUNLOAD:
4231					 printk(OSST_DEB_MSG "%s:D: Unloading tape.\n", name);
4232					 break;
4233				 case MTLOAD:
4234					 printk(OSST_DEB_MSG "%s:D: Loading tape.\n", name);
4235					 break;
4236				 case MTRETEN:
4237					 printk(OSST_DEB_MSG "%s:D: Retensioning tape.\n", name);
4238					 break;
4239				 case MTOFFL:
4240					 printk(OSST_DEB_MSG "%s:D: Ejecting tape.\n", name);
4241					 break;
4242			 }
4243		 }
4244#endif
4245       fileno = blkno = at_sm = frame_seq_numbr = logical_blk_num = 0 ;
4246		 break;
4247	 case MTNOP:
4248#if DEBUG
4249		 if (debugging)
4250			 printk(OSST_DEB_MSG "%s:D: No-op on tape.\n", name);
4251#endif
4252		 return 0;  /* Should do something ? */
4253		 break;
4254	 case MTEOM:
4255#if DEBUG
4256		if (debugging)
4257		   printk(OSST_DEB_MSG "%s:D: Spacing to end of recorded medium.\n", name);
4258#endif
4259		if ((osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos) < 0) ||
4260			    (osst_get_logical_frame(STp, &SRpnt, -1, 0)               < 0)) {
4261		   ioctl_result = -EIO;
4262		   goto os_bypass;
4263		}
4264		if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_EOD) {
4265#if DEBUG
4266		   printk(OSST_DEB_MSG "%s:D: No EOD frame found where expected.\n", name);
4267#endif
4268		   ioctl_result = -EIO;
4269		   goto os_bypass;
4270		}
4271		ioctl_result = osst_set_frame_position(STp, &SRpnt, STp->eod_frame_ppos, 0);
4272		fileno = STp->filemark_cnt;
4273		blkno  = at_sm = 0;
4274		goto os_bypass;
4275
4276	 case MTERASE:
4277		if (STp->write_prot)
4278		   return (-EACCES);
4279		ioctl_result = osst_reset_header(STp, &SRpnt);
4280		i = osst_write_eod(STp, &SRpnt);
4281		if (i < ioctl_result) ioctl_result = i;
4282		i = osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos);
4283		if (i < ioctl_result) ioctl_result = i;
4284		fileno = blkno = at_sm = 0 ;
4285		goto os_bypass;
4286
4287	 case MTREW:
4288		cmd[0] = REZERO_UNIT; /* rewind */
4289		cmd[1] = 1;
4290#if DEBUG
4291		if (debugging)
4292		   printk(OSST_DEB_MSG "%s:D: Rewinding tape, Immed=%d.\n", name, cmd[1]);
4293#endif
4294		fileno = blkno = at_sm = frame_seq_numbr = logical_blk_num = 0 ;
4295		break;
4296
4297	 case MTSETBLK:           /* Set block length */
4298		 if ((STps->drv_block == 0 )			  &&
4299		     !STp->dirty				  &&
4300		     ((STp->buffer)->buffer_bytes == 0)		  &&
4301		     ((arg & MT_ST_BLKSIZE_MASK) >= 512 )	  && 
4302		     ((arg & MT_ST_BLKSIZE_MASK) <= OS_DATA_SIZE) &&
4303		     !(OS_DATA_SIZE % (arg & MT_ST_BLKSIZE_MASK))  ) {
4304			 /*
4305			  * Only allowed to change the block size if you opened the
4306			  * device at the beginning of a file before writing anything.
4307			  * Note, that when reading, changing block_size is futile,
4308			  * as the size used when writing overrides it.
4309			  */
4310			 STp->block_size = (arg & MT_ST_BLKSIZE_MASK);
4311			 printk(KERN_INFO "%s:I: Block size set to %d bytes.\n",
4312					   name, STp->block_size);
4313			 return 0;
4314		 }
4315	 case MTSETDENSITY:       /* Set tape density */
4316	 case MTSETDRVBUFFER:     /* Set drive buffering */
4317	 case SET_DENS_AND_BLK:   /* Set density and block size */
4318		 chg_eof = 0;
4319		 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
4320			 return (-EIO);       /* Not allowed if data in buffer */
4321		 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
4322		     (arg & MT_ST_BLKSIZE_MASK) != 0                    &&
4323		     (arg & MT_ST_BLKSIZE_MASK) != STp->block_size       ) {
4324			 printk(KERN_WARNING "%s:W: Illegal to set block size to %d%s.\n",
4325						name, (int)(arg & MT_ST_BLKSIZE_MASK),
4326						(OS_DATA_SIZE % (arg & MT_ST_BLKSIZE_MASK))?"":" now");
4327			 return (-EINVAL);
4328		 }
4329		 return 0;  /* FIXME silently ignore if block size didn't change */
4330
4331	 default:
4332		return (-ENOSYS);
4333	}
4334
4335	SRpnt = osst_do_scsi(SRpnt, STp, cmd, datalen, direction, timeout, MAX_RETRIES, 1);
4336
4337	ioctl_result = (STp->buffer)->syscall_result;
4338
4339	if (!SRpnt) {
4340#if DEBUG
4341		printk(OSST_DEB_MSG "%s:D: Couldn't exec scsi cmd for IOCTL\n", name);
4342#endif
4343		return ioctl_result;
4344	}
4345
4346	if (!ioctl_result) {  /* SCSI command successful */
4347		STp->frame_seq_number = frame_seq_numbr;
4348		STp->logical_blk_num  = logical_blk_num;
4349	}
4350
4351os_bypass:
4352#if DEBUG
4353	if (debugging)
4354		printk(OSST_DEB_MSG "%s:D: IOCTL (%d) Result=%d\n", name, cmd_in, ioctl_result);
4355#endif
4356
4357	if (!ioctl_result) {				/* success */
4358
4359		if (cmd_in == MTFSFM) {
4360			 fileno--;
4361			 blkno--;
4362		}
4363		if (cmd_in == MTBSFM) {
4364			 fileno++;
4365			 blkno++;
4366		}
4367		STps->drv_block = blkno;
4368		STps->drv_file = fileno;
4369		STps->at_sm = at_sm;
4370
4371		if (cmd_in == MTEOM)
4372			STps->eof = ST_EOD;
4373		else if ((cmd_in == MTFSFM || cmd_in == MTBSF) && STps->eof == ST_FM_HIT) {
4374			ioctl_result = osst_seek_logical_blk(STp, &SRpnt, STp->logical_blk_num-1);
4375			STps->drv_block++;
4376			STp->logical_blk_num++;
4377			STp->frame_seq_number++;
4378			STp->frame_in_buffer = 0;
4379			STp->buffer->read_pointer = 0;
4380		}
4381		else if (cmd_in == MTFSF)
4382			STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_FM;
4383		else if (chg_eof)
4384			STps->eof = ST_NOEOF;
4385
4386		if (cmd_in == MTOFFL || cmd_in == MTUNLOAD)
4387			STp->rew_at_close = 0;
4388		else if (cmd_in == MTLOAD) {
4389			for (i=0; i < ST_NBR_PARTITIONS; i++) {
4390			    STp->ps[i].rw = ST_IDLE;
4391			    STp->ps[i].last_block_valid = 0;/* FIXME - where else is this field maintained? */
4392			}
4393			STp->partition = 0;
4394		}
4395
4396		if (cmd_in == MTREW) {
4397			ioctl_result = osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos); 
4398			if (ioctl_result > 0)
4399				ioctl_result = 0;
4400		}
4401
4402	} else if (cmd_in == MTBSF || cmd_in == MTBSFM ) {
4403		if (osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos) < 0)
4404			STps->drv_file = STps->drv_block = -1;
4405		else
4406			STps->drv_file = STps->drv_block = 0;
4407		STps->eof = ST_NOEOF;
4408	} else if (cmd_in == MTFSF || cmd_in == MTFSFM) {
4409		if (osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos) < 0)
4410			STps->drv_file = STps->drv_block = -1;
4411		else {
4412			STps->drv_file  = STp->filemark_cnt;
4413			STps->drv_block = 0;
4414		}
4415		STps->eof = ST_EOD;
4416	} else if (cmd_in == MTBSR || cmd_in == MTFSR || cmd_in == MTWEOF || cmd_in == MTEOM) {
4417		STps->drv_file = STps->drv_block = (-1);
4418		STps->eof = ST_NOEOF;
4419		STp->header_ok = 0;
4420	} else if (cmd_in == MTERASE) {
4421		STp->header_ok = 0;
4422	} else if (SRpnt) {  /* SCSI command was not completely successful. */
4423		if (SRpnt->sense[2] & 0x40) {
4424			STps->eof = ST_EOM_OK;
4425			STps->drv_block = 0;
4426		}
4427		if (chg_eof)
4428			STps->eof = ST_NOEOF;
4429
4430		if ((SRpnt->sense[2] & 0x0f) == BLANK_CHECK)
4431			STps->eof = ST_EOD;
4432
4433		if (cmd_in == MTLOAD && osst_wait_for_medium(STp, &SRpnt, 60))
4434			ioctl_result = osst_wait_ready(STp, &SRpnt, 5 * 60, OSST_WAIT_POSITION_COMPLETE);
4435	}
4436	*aSRpnt = SRpnt;
4437
4438	return ioctl_result;
4439}
4440
4441
4442/* Open the device */
4443static int __os_scsi_tape_open(struct inode * inode, struct file * filp)
4444{
4445	unsigned short	      flags;
4446	int		      i, b_size, new_session = 0, retval = 0;
4447	unsigned char	      cmd[MAX_COMMAND_SIZE];
4448	struct osst_request * SRpnt = NULL;
4449	struct osst_tape    * STp;
4450	struct st_modedef   * STm;
4451	struct st_partstat  * STps;
4452	char		    * name;
4453	int		      dev  = TAPE_NR(inode);
4454	int		      mode = TAPE_MODE(inode);
4455
4456	/*
4457	 * We really want to do nonseekable_open(inode, filp); here, but some
4458	 * versions of tar incorrectly call lseek on tapes and bail out if that
4459	 * fails.  So we disallow pread() and pwrite(), but permit lseeks.
4460	 */
4461	filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
4462
4463	write_lock(&os_scsi_tapes_lock);
4464	if (dev >= osst_max_dev || os_scsi_tapes == NULL ||
4465	    (STp = os_scsi_tapes[dev]) == NULL || !STp->device) {
4466		write_unlock(&os_scsi_tapes_lock);
4467		return (-ENXIO);
4468	}
4469
4470	name = tape_name(STp);
4471
4472	if (STp->in_use) {
4473		write_unlock(&os_scsi_tapes_lock);
4474#if DEBUG
4475		printk(OSST_DEB_MSG "%s:D: Device already in use.\n", name);
4476#endif
4477		return (-EBUSY);
4478	}
4479	if (scsi_device_get(STp->device)) {
4480		write_unlock(&os_scsi_tapes_lock);
4481#if DEBUG
4482                printk(OSST_DEB_MSG "%s:D: Failed scsi_device_get.\n", name);
4483#endif
4484		return (-ENXIO);
4485	}
4486	filp->private_data = STp;
4487	STp->in_use = 1;
4488	write_unlock(&os_scsi_tapes_lock);
4489	STp->rew_at_close = TAPE_REWIND(inode);
4490
4491	if( !scsi_block_when_processing_errors(STp->device) ) {
4492		return -ENXIO;
4493	}
4494
4495	if (mode != STp->current_mode) {
4496#if DEBUG
4497		if (debugging)
4498			printk(OSST_DEB_MSG "%s:D: Mode change from %d to %d.\n",
4499					       name, STp->current_mode, mode);
4500#endif
4501		new_session = 1;
4502		STp->current_mode = mode;
4503	}
4504	STm = &(STp->modes[STp->current_mode]);
4505
4506	flags = filp->f_flags;
4507	STp->write_prot = ((flags & O_ACCMODE) == O_RDONLY);
4508
4509	STp->raw = TAPE_IS_RAW(inode);
4510	if (STp->raw)
4511		STp->header_ok = 0;
4512
4513	/* Allocate data segments for this device's tape buffer */
4514	if (!enlarge_buffer(STp->buffer, STp->restr_dma)) {
4515		printk(KERN_ERR "%s:E: Unable to allocate memory segments for tape buffer.\n", name);
4516		retval = (-EOVERFLOW);
4517		goto err_out;
4518	}
4519	if (STp->buffer->buffer_size >= OS_FRAME_SIZE) {
4520		for (i = 0, b_size = 0; 
4521		     (i < STp->buffer->sg_segs) && ((b_size + STp->buffer->sg[i].length) <= OS_DATA_SIZE); 
4522		     b_size += STp->buffer->sg[i++].length);
4523		STp->buffer->aux = (os_aux_t *) (page_address(sg_page(&STp->buffer->sg[i])) + OS_DATA_SIZE - b_size);
4524#if DEBUG
4525		printk(OSST_DEB_MSG "%s:D: b_data points to %p in segment 0 at %p\n", name,
4526			STp->buffer->b_data, page_address(STp->buffer->sg[0].page));
4527		printk(OSST_DEB_MSG "%s:D: AUX points to %p in segment %d at %p\n", name,
4528			 STp->buffer->aux, i, page_address(STp->buffer->sg[i].page));
4529#endif
4530	} else {
4531		STp->buffer->aux = NULL; /* this had better never happen! */
4532		printk(KERN_NOTICE "%s:A: Framesize %d too large for buffer.\n", name, OS_FRAME_SIZE);
4533		retval = (-EIO);
4534		goto err_out;
4535	}
4536	STp->buffer->writing = 0;
4537	STp->buffer->syscall_result = 0;
4538	STp->dirty = 0;
4539	for (i=0; i < ST_NBR_PARTITIONS; i++) {
4540		STps = &(STp->ps[i]);
4541		STps->rw = ST_IDLE;
4542	}
4543	STp->ready = ST_READY;
4544#if DEBUG
4545	STp->nbr_waits = STp->nbr_finished = 0;
4546#endif
4547
4548	memset (cmd, 0, MAX_COMMAND_SIZE);
4549	cmd[0] = TEST_UNIT_READY;
4550
4551	SRpnt = osst_do_scsi(NULL, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
4552	if (!SRpnt) {
4553		retval = (STp->buffer)->syscall_result;		/* FIXME - valid? */
4554		goto err_out;
4555	}
4556	if ((SRpnt->sense[0] & 0x70) == 0x70      &&
4557	    (SRpnt->sense[2] & 0x0f) == NOT_READY &&
4558	     SRpnt->sense[12]        == 4         ) {
4559#if DEBUG
4560		printk(OSST_DEB_MSG "%s:D: Unit not ready, cause %x\n", name, SRpnt->sense[13]);
4561#endif
4562		if (filp->f_flags & O_NONBLOCK) {
4563			retval = -EAGAIN;
4564			goto err_out;
4565		}
4566		if (SRpnt->sense[13] == 2) {	/* initialize command required (LOAD) */
4567			memset (cmd, 0, MAX_COMMAND_SIZE);
4568        		cmd[0] = START_STOP;
4569			cmd[1] = 1;
4570			cmd[4] = 1;
4571			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4572					     STp->timeout, MAX_RETRIES, 1);
4573		}
4574		osst_wait_ready(STp, &SRpnt, (SRpnt->sense[13]==1?15:3) * 60, 0);
4575	}
4576	if ((SRpnt->sense[0] & 0x70) == 0x70 &&
4577	    (SRpnt->sense[2] & 0x0f) == UNIT_ATTENTION) { /* New media? */
4578#if DEBUG
4579		printk(OSST_DEB_MSG "%s:D: Unit wants attention\n", name);
4580#endif
4581		STp->header_ok = 0;
4582
4583		for (i=0; i < 10; i++) {
4584
4585			memset (cmd, 0, MAX_COMMAND_SIZE);
4586			cmd[0] = TEST_UNIT_READY;
4587
4588			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4589					     STp->timeout, MAX_RETRIES, 1);
4590			if ((SRpnt->sense[0] & 0x70) != 0x70 ||
4591			    (SRpnt->sense[2] & 0x0f) != UNIT_ATTENTION)
4592				break;
4593		}
4594
4595		STp->pos_unknown = 0;
4596		STp->partition = STp->new_partition = 0;
4597		if (STp->can_partitions)
4598			STp->nbr_partitions = 1;  /* This guess will be updated later if necessary */
4599		for (i=0; i < ST_NBR_PARTITIONS; i++) {
4600			STps = &(STp->ps[i]);
4601			STps->rw = ST_IDLE;		/* FIXME - seems to be redundant... */
4602			STps->eof = ST_NOEOF;
4603			STps->at_sm = 0;
4604			STps->last_block_valid = 0;
4605			STps->drv_block = 0;
4606			STps->drv_file = 0 ;
4607		}
4608		new_session = 1;
4609		STp->recover_count = 0;
4610		STp->abort_count = 0;
4611	}
4612	/*
4613	 * if we have valid headers from before, and the drive/tape seem untouched,
4614	 * open without reconfiguring and re-reading the headers
4615	 */
4616	if (!STp->buffer->syscall_result && STp->header_ok &&
4617	    !SRpnt->result && SRpnt->sense[0] == 0) {
4618
4619		memset(cmd, 0, MAX_COMMAND_SIZE);
4620		cmd[0] = MODE_SENSE;
4621		cmd[1] = 8;
4622		cmd[2] = VENDOR_IDENT_PAGE;
4623		cmd[4] = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH;
4624
4625		SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
4626
4627		if (STp->buffer->syscall_result                     ||
4628		    STp->buffer->b_data[MODE_HEADER_LENGTH + 2] != 'L' ||
4629		    STp->buffer->b_data[MODE_HEADER_LENGTH + 3] != 'I' ||
4630		    STp->buffer->b_data[MODE_HEADER_LENGTH + 4] != 'N' ||
4631		    STp->buffer->b_data[MODE_HEADER_LENGTH + 5] != '4'  ) {
4632#if DEBUG
4633			printk(OSST_DEB_MSG "%s:D: Signature was changed to %c%c%c%c\n", name,
4634			  STp->buffer->b_data[MODE_HEADER_LENGTH + 2],
4635			  STp->buffer->b_data[MODE_HEADER_LENGTH + 3],
4636			  STp->buffer->b_data[MODE_HEADER_LENGTH + 4],
4637			  STp->buffer->b_data[MODE_HEADER_LENGTH + 5]);
4638#endif
4639			STp->header_ok = 0;
4640		}
4641		i = STp->first_frame_position;
4642		if (STp->header_ok && i == osst_get_frame_position(STp, &SRpnt)) {
4643			if (STp->door_locked == ST_UNLOCKED) {
4644				if (do_door_lock(STp, 1))
4645					printk(KERN_INFO "%s:I: Can't lock drive door\n", name);
4646				else
4647					STp->door_locked = ST_LOCKED_AUTO;
4648			}
4649			if (!STp->frame_in_buffer) {
4650				STp->block_size = (STm->default_blksize > 0) ?
4651							STm->default_blksize : OS_DATA_SIZE;
4652				STp->buffer->buffer_bytes = STp->buffer->read_pointer = 0;
4653			}
4654			STp->buffer->buffer_blocks = OS_DATA_SIZE / STp->block_size;
4655			STp->fast_open = 1;
4656			osst_release_request(SRpnt);
4657			return 0;
4658		}
4659#if DEBUG
4660		if (i != STp->first_frame_position)
4661			printk(OSST_DEB_MSG "%s:D: Tape position changed from %d to %d\n",
4662						name, i, STp->first_frame_position);
4663#endif
4664		STp->header_ok = 0;
4665	}
4666	STp->fast_open = 0;
4667
4668	if ((STp->buffer)->syscall_result != 0 &&   /* in all error conditions except no medium */ 
4669	    (SRpnt->sense[2] != 2 || SRpnt->sense[12] != 0x3A) ) {
4670
4671		memset(cmd, 0, MAX_COMMAND_SIZE);
4672		cmd[0] = MODE_SELECT;
4673		cmd[1] = 0x10;
4674		cmd[4] = 4 + MODE_HEADER_LENGTH;
4675
4676		(STp->buffer)->b_data[0] = cmd[4] - 1;
4677		(STp->buffer)->b_data[1] = 0;			/* Medium Type - ignoring */
4678		(STp->buffer)->b_data[2] = 0;			/* Reserved */
4679		(STp->buffer)->b_data[3] = 0;			/* Block Descriptor Length */
4680		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = 0x3f;
4681		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 1;
4682		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 2;
4683		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = 3;
4684
4685#if DEBUG
4686		printk(OSST_DEB_MSG "%s:D: Applying soft reset\n", name);
4687#endif
4688		SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
4689
4690		STp->header_ok = 0;
4691
4692		for (i=0; i < 10; i++) {
4693
4694			memset (cmd, 0, MAX_COMMAND_SIZE);
4695			cmd[0] = TEST_UNIT_READY;
4696
4697			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4698						    STp->timeout, MAX_RETRIES, 1);
4699			if ((SRpnt->sense[0] & 0x70) != 0x70 ||
4700			    (SRpnt->sense[2] & 0x0f) == NOT_READY)
4701			break;
4702
4703			if ((SRpnt->sense[2] & 0x0f) == UNIT_ATTENTION) {
4704				int j;
4705
4706				STp->pos_unknown = 0;
4707				STp->partition = STp->new_partition = 0;
4708				if (STp->can_partitions)
4709					STp->nbr_partitions = 1;  /* This guess will be updated later if necessary */
4710				for (j = 0; j < ST_NBR_PARTITIONS; j++) {
4711					STps = &(STp->ps[j]);
4712					STps->rw = ST_IDLE;
4713					STps->eof = ST_NOEOF;
4714					STps->at_sm = 0;
4715					STps->last_block_valid = 0;
4716					STps->drv_block = 0;
4717					STps->drv_file = 0 ;
4718				}
4719				new_session = 1;
4720			}
4721		}
4722	}
4723
4724	if (osst_wait_ready(STp, &SRpnt, 15 * 60, 0))		/* FIXME - not allowed with NOBLOCK */
4725		 printk(KERN_INFO "%s:I: Device did not become Ready in open\n", name);
4726
4727	if ((STp->buffer)->syscall_result != 0) {
4728		if ((STp->device)->scsi_level >= SCSI_2 &&
4729		    (SRpnt->sense[0] & 0x70) == 0x70 &&
4730		    (SRpnt->sense[2] & 0x0f) == NOT_READY &&
4731		     SRpnt->sense[12] == 0x3a) { /* Check ASC */
4732			STp->ready = ST_NO_TAPE;
4733		} else
4734			STp->ready = ST_NOT_READY;
4735		osst_release_request(SRpnt);
4736		SRpnt = NULL;
4737		STp->density = 0;   	/* Clear the erroneous "residue" */
4738		STp->write_prot = 0;
4739		STp->block_size = 0;
4740		STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
4741		STp->partition = STp->new_partition = 0;
4742		STp->door_locked = ST_UNLOCKED;
4743		return 0;
4744	}
4745
4746	osst_configure_onstream(STp, &SRpnt);
4747
4748	STp->block_size = STp->raw ? OS_FRAME_SIZE : (
4749			     (STm->default_blksize > 0) ? STm->default_blksize : OS_DATA_SIZE);
4750	STp->buffer->buffer_blocks = STp->raw ? 1 : OS_DATA_SIZE / STp->block_size;
4751	STp->buffer->buffer_bytes  =
4752	STp->buffer->read_pointer  =
4753	STp->frame_in_buffer       = 0;
4754
4755#if DEBUG
4756	if (debugging)
4757		printk(OSST_DEB_MSG "%s:D: Block size: %d, frame size: %d, buffer size: %d (%d blocks).\n",
4758		     name, STp->block_size, OS_FRAME_SIZE, (STp->buffer)->buffer_size,
4759		     (STp->buffer)->buffer_blocks);
4760#endif
4761
4762	if (STp->drv_write_prot) {
4763		STp->write_prot = 1;
4764#if DEBUG
4765		if (debugging)
4766			printk(OSST_DEB_MSG "%s:D: Write protected\n", name);
4767#endif
4768		if ((flags & O_ACCMODE) == O_WRONLY || (flags & O_ACCMODE) == O_RDWR) {
4769			retval = (-EROFS);
4770			goto err_out;
4771		}
4772	}
4773
4774	if (new_session) {  /* Change the drive parameters for the new mode */
4775#if DEBUG
4776		if (debugging)
4777	printk(OSST_DEB_MSG "%s:D: New Session\n", name);
4778#endif
4779		STp->density_changed = STp->blksize_changed = 0;
4780		STp->compression_changed = 0;
4781	}
4782
4783	/*
4784	 * properly position the tape and check the ADR headers
4785	 */
4786	if (STp->door_locked == ST_UNLOCKED) {
4787		 if (do_door_lock(STp, 1))
4788			printk(KERN_INFO "%s:I: Can't lock drive door\n", name);
4789		 else
4790			STp->door_locked = ST_LOCKED_AUTO;
4791	}
4792
4793	osst_analyze_headers(STp, &SRpnt);
4794
4795	osst_release_request(SRpnt);
4796	SRpnt = NULL;
4797
4798	return 0;
4799
4800err_out:
4801	if (SRpnt != NULL)
4802		osst_release_request(SRpnt);
4803	normalize_buffer(STp->buffer);
4804	STp->header_ok = 0;
4805	STp->in_use = 0;
4806	scsi_device_put(STp->device);
4807
4808	return retval;
4809}
4810
4811/* BKL pushdown: spaghetti avoidance wrapper */
4812static int os_scsi_tape_open(struct inode * inode, struct file * filp)
4813{
4814	int ret;
4815
4816	mutex_lock(&osst_int_mutex);
4817	ret = __os_scsi_tape_open(inode, filp);
4818	mutex_unlock(&osst_int_mutex);
4819	return ret;
4820}
4821
4822
4823
4824/* Flush the tape buffer before close */
4825static int os_scsi_tape_flush(struct file * filp, fl_owner_t id)
4826{
4827	int		      result = 0, result2;
4828	struct osst_tape    * STp    = filp->private_data;
4829	struct st_modedef   * STm    = &(STp->modes[STp->current_mode]);
4830	struct st_partstat  * STps   = &(STp->ps[STp->partition]);
4831	struct osst_request * SRpnt  = NULL;
4832	char		    * name   = tape_name(STp);
4833
4834	if (file_count(filp) > 1)
4835		return 0;
4836
4837	if ((STps->rw == ST_WRITING || STp->dirty) && !STp->pos_unknown) {
4838		STp->write_type = OS_WRITE_DATA;
4839		result = osst_flush_write_buffer(STp, &SRpnt);
4840		if (result != 0 && result != (-ENOSPC))
4841			goto out;
4842	}
4843	if ( STps->rw >= ST_WRITING && !STp->pos_unknown) {
4844
4845#if DEBUG
4846		if (debugging) {
4847			printk(OSST_DEB_MSG "%s:D: File length %ld bytes.\n",
4848					       name, (long)(filp->f_pos));
4849			printk(OSST_DEB_MSG "%s:D: Async write waits %d, finished %d.\n",
4850					       name, STp->nbr_waits, STp->nbr_finished);
4851		}
4852#endif
4853		result = osst_write_trailer(STp, &SRpnt, !(STp->rew_at_close));
4854#if DEBUG
4855		if (debugging)
4856			printk(OSST_DEB_MSG "%s:D: Buffer flushed, %d EOF(s) written\n",
4857					       name, 1+STp->two_fm);
4858#endif
4859	}
4860	else if (!STp->rew_at_close) {
4861		STps = &(STp->ps[STp->partition]);
4862		if (!STm->sysv || STps->rw != ST_READING) {
4863			if (STp->can_bsr)
4864				result = osst_flush_buffer(STp, &SRpnt, 0); /* this is the default path */
4865			else if (STps->eof == ST_FM_HIT) {
4866				result = cross_eof(STp, &SRpnt, 0);
4867					if (result) {
4868						if (STps->drv_file >= 0)
4869							STps->drv_file++;
4870						STps->drv_block = 0;
4871						STps->eof = ST_FM;
4872					}
4873					else
4874						STps->eof = ST_NOEOF;
4875			}
4876		}
4877		else if ((STps->eof == ST_NOEOF &&
4878			  !(result = cross_eof(STp, &SRpnt, 1))) ||
4879			 STps->eof == ST_FM_HIT) {
4880			if (STps->drv_file >= 0)
4881				STps->drv_file++;
4882			STps->drv_block = 0;
4883			STps->eof = ST_FM;
4884		}
4885	}
4886
4887out:
4888	if (STp->rew_at_close) {
4889		result2 = osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos);
4890		STps->drv_file = STps->drv_block = STp->frame_seq_number = STp->logical_blk_num = 0;
4891		if (result == 0 && result2 < 0)
4892			result = result2;
4893	}
4894	if (SRpnt) osst_release_request(SRpnt);
4895
4896	if (STp->abort_count || STp->recover_count) {
4897		printk(KERN_INFO "%s:I:", name);
4898		if (STp->abort_count)
4899			printk(" %d unrecovered errors", STp->abort_count);
4900		if (STp->recover_count)
4901			printk(" %d recovered errors", STp->recover_count);
4902		if (STp->write_count)
4903			printk(" in %d frames written", STp->write_count);
4904		if (STp->read_count)
4905			printk(" in %d frames read", STp->read_count);
4906		printk("\n");
4907		STp->recover_count = 0;
4908		STp->abort_count   = 0;
4909	}
4910	STp->write_count = 0;
4911	STp->read_count  = 0;
4912
4913	return result;
4914}
4915
4916
4917/* Close the device and release it */
4918static int os_scsi_tape_close(struct inode * inode, struct file * filp)
4919{
4920	int		      result = 0;
4921	struct osst_tape    * STp    = filp->private_data;
4922
4923	if (STp->door_locked == ST_LOCKED_AUTO)
4924		do_door_lock(STp, 0);
4925
4926	if (STp->raw)
4927		STp->header_ok = 0;
4928	
4929	normalize_buffer(STp->buffer);
4930	write_lock(&os_scsi_tapes_lock);
4931	STp->in_use = 0;
4932	write_unlock(&os_scsi_tapes_lock);
4933
4934	scsi_device_put(STp->device);
4935
4936	return result;
4937}
4938
4939
4940/* The ioctl command */
4941static long osst_ioctl(struct file * file,
4942	 unsigned int cmd_in, unsigned long arg)
4943{
4944	int		      i, cmd_nr, cmd_type, blk, retval = 0;
4945	struct st_modedef   * STm;
4946	struct st_partstat  * STps;
4947	struct osst_request * SRpnt = NULL;
4948	struct osst_tape    * STp   = file->private_data;
4949	char		    * name  = tape_name(STp);
4950	void	    __user  * p     = (void __user *)arg;
4951
4952	mutex_lock(&osst_int_mutex);
4953	if (mutex_lock_interruptible(&STp->lock)) {
4954		mutex_unlock(&osst_int_mutex);
4955		return -ERESTARTSYS;
4956	}
4957
4958#if DEBUG
4959	if (debugging && !STp->in_use) {
4960		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
4961		retval = (-EIO);
4962		goto out;
4963	}
4964#endif
4965	STm = &(STp->modes[STp->current_mode]);
4966	STps = &(STp->ps[STp->partition]);
4967
4968	/*
4969	 * If we are in the middle of error recovery, don't let anyone
4970	 * else try and use this device.  Also, if error recovery fails, it
4971	 * may try and take the device offline, in which case all further
4972	 * access to the device is prohibited.
4973	 */
4974	retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
4975			file->f_flags & O_NDELAY);
4976	if (retval)
4977		goto out;
 
4978
4979	cmd_type = _IOC_TYPE(cmd_in);
4980	cmd_nr   = _IOC_NR(cmd_in);
4981#if DEBUG
4982	printk(OSST_DEB_MSG "%s:D: Ioctl %d,%d in %s mode\n", name,
4983			    cmd_type, cmd_nr, STp->raw?"raw":"normal");
4984#endif
4985	if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
4986		struct mtop mtc;
4987		int    auto_weof = 0;
4988
4989		if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
4990			retval = (-EINVAL);
4991			goto out;
4992		}
4993
4994		i = copy_from_user((char *) &mtc, p, sizeof(struct mtop));
4995		if (i) {
4996			retval = (-EFAULT);
4997			goto out;
4998		}
4999
5000		if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
5001			printk(KERN_WARNING "%s:W: MTSETDRVBUFFER only allowed for root.\n", name);
5002			retval = (-EPERM);
5003			goto out;
5004		}
5005
5006		if (!STm->defined && (mtc.mt_op != MTSETDRVBUFFER && (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
5007			retval = (-ENXIO);
5008			goto out;
5009		}
5010
5011		if (!STp->pos_unknown) {
5012
5013			if (STps->eof == ST_FM_HIT) {
5014				if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM|| mtc.mt_op == MTEOM) {
5015					mtc.mt_count -= 1;
5016					if (STps->drv_file >= 0)
5017						STps->drv_file += 1;
5018				}
5019				else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
5020					mtc.mt_count += 1;
5021					if (STps->drv_file >= 0)
5022						STps->drv_file += 1;
5023				}
5024			}
5025
5026			if (mtc.mt_op == MTSEEK) {
5027				/* Old position must be restored if partition will be changed */
5028				i = !STp->can_partitions || (STp->new_partition != STp->partition);
5029			}
5030			else {
5031				i = mtc.mt_op == MTREW   || mtc.mt_op == MTOFFL ||
5032				    mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM  ||
5033				    mtc.mt_op == MTLOCK  || mtc.mt_op == MTLOAD ||
5034				    mtc.mt_op == MTFSF   || mtc.mt_op == MTFSFM ||
5035				    mtc.mt_op == MTBSF   || mtc.mt_op == MTBSFM ||
5036				    mtc.mt_op == MTCOMPRESSION;
5037			}
5038			i = osst_flush_buffer(STp, &SRpnt, i);
5039			if (i < 0) {
5040				retval = i;
5041				goto out;
5042			}
5043		}
5044		else {
5045			/*
5046			 * If there was a bus reset, block further access
5047			 * to this device.  If the user wants to rewind the tape,
5048			 * then reset the flag and allow access again.
5049			 */
5050			if(mtc.mt_op != MTREW   &&
5051			   mtc.mt_op != MTOFFL  &&
5052			   mtc.mt_op != MTRETEN &&
5053			   mtc.mt_op != MTERASE &&
5054			   mtc.mt_op != MTSEEK  &&
5055			   mtc.mt_op != MTEOM)   {
5056				retval = (-EIO);
5057				goto out;
5058			}
5059			reset_state(STp);
5060			/* remove this when the midlevel properly clears was_reset */
5061			STp->device->was_reset = 0;
5062		}
5063
5064		if (mtc.mt_op != MTCOMPRESSION  && mtc.mt_op != MTLOCK         &&
5065		    mtc.mt_op != MTNOP          && mtc.mt_op != MTSETBLK       &&
5066		    mtc.mt_op != MTSETDENSITY   && mtc.mt_op != MTSETDRVBUFFER && 
5067		    mtc.mt_op != MTMKPART       && mtc.mt_op != MTSETPART      &&
5068		    mtc.mt_op != MTWEOF         && mtc.mt_op != MTWSM           ) {
5069
5070			/*
5071			 * The user tells us to move to another position on the tape.
5072			 * If we were appending to the tape content, that would leave
5073			 * the tape without proper end, in that case write EOD and
5074			 * update the header to reflect its position.
5075			 */
5076#if DEBUG
5077			printk(KERN_WARNING "%s:D: auto_weod %s at ffp=%d,efp=%d,fsn=%d,lbn=%d,fn=%d,bn=%d\n", name,
5078					STps->rw >= ST_WRITING ? "write" : STps->rw == ST_READING ? "read" : "idle",
5079					STp->first_frame_position, STp->eod_frame_ppos, STp->frame_seq_number,
5080					STp->logical_blk_num, STps->drv_file, STps->drv_block );
5081#endif
5082			if (STps->rw >= ST_WRITING && STp->first_frame_position >= STp->eod_frame_ppos) {
5083				auto_weof = ((STp->write_type != OS_WRITE_NEW_MARK) &&
5084							!(mtc.mt_op == MTREW || mtc.mt_op == MTOFFL));
5085				i = osst_write_trailer(STp, &SRpnt,
5086							!(mtc.mt_op == MTREW || mtc.mt_op == MTOFFL));
5087#if DEBUG
5088				printk(KERN_WARNING "%s:D: post trailer xeof=%d,ffp=%d,efp=%d,fsn=%d,lbn=%d,fn=%d,bn=%d\n",
5089						name, auto_weof, STp->first_frame_position, STp->eod_frame_ppos,
5090						STp->frame_seq_number, STp->logical_blk_num, STps->drv_file, STps->drv_block );
5091#endif
5092				if (i < 0) {
5093					retval = i;
5094					goto out;
5095				}
5096			}
5097			STps->rw = ST_IDLE;
5098		}
5099
5100		if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
5101			do_door_lock(STp, 0);  /* Ignore result! */
5102
5103		if (mtc.mt_op == MTSETDRVBUFFER &&
5104		   (mtc.mt_count & MT_ST_OPTIONS) != 0) {
5105			retval = osst_set_options(STp, mtc.mt_count);
5106			goto out;
5107		}
5108
5109		if (mtc.mt_op == MTSETPART) {
5110			if (mtc.mt_count >= STp->nbr_partitions)
5111				retval = -EINVAL;
5112			else {
5113				STp->new_partition = mtc.mt_count;
5114				retval = 0;
5115			}
5116			goto out;
5117		}
5118
5119		if (mtc.mt_op == MTMKPART) {
5120			if (!STp->can_partitions) {
5121				retval = (-EINVAL);
5122				goto out;
5123			}
5124			if ((i = osst_int_ioctl(STp, &SRpnt, MTREW, 0)) < 0 /*||
5125			    (i = partition_tape(inode, mtc.mt_count)) < 0*/) {
5126				retval = i;
5127				goto out;
5128			}
5129			for (i=0; i < ST_NBR_PARTITIONS; i++) {
5130				STp->ps[i].rw = ST_IDLE;
5131				STp->ps[i].at_sm = 0;
5132				STp->ps[i].last_block_valid = 0;
5133			}
5134			STp->partition = STp->new_partition = 0;
5135			STp->nbr_partitions = 1;  /* Bad guess ?-) */
5136			STps->drv_block = STps->drv_file = 0;
5137			retval = 0;
5138			goto out;
5139	 	}
5140
5141		if (mtc.mt_op == MTSEEK) {
5142			if (STp->raw)
5143				i = osst_set_frame_position(STp, &SRpnt, mtc.mt_count, 0);
5144			else
5145				i = osst_seek_sector(STp, &SRpnt, mtc.mt_count);
5146			if (!STp->can_partitions)
5147				STp->ps[0].rw = ST_IDLE;
5148			retval = i;
5149			goto out;
5150		}
5151 
5152		if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
5153			retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
5154			goto out;
5155		}
5156
5157		if (auto_weof)
5158			cross_eof(STp, &SRpnt, 0);
5159
5160		if (mtc.mt_op == MTCOMPRESSION)
5161			retval = -EINVAL;       /* OnStream drives don't have compression hardware */
5162		else
5163			/* MTBSF MTBSFM MTBSR MTBSS MTEOM MTERASE MTFSF MTFSFB MTFSR MTFSS
5164			 * MTLOAD MTOFFL MTRESET MTRETEN MTREW MTUNLOAD MTWEOF MTWSM */
5165			retval = osst_int_ioctl(STp, &SRpnt, mtc.mt_op, mtc.mt_count);
5166		goto out;
5167	}
5168
5169	if (!STm->defined) {
5170		retval = (-ENXIO);
5171		goto out;
5172	}
5173
5174	if ((i = osst_flush_buffer(STp, &SRpnt, 0)) < 0) {
5175		retval = i;
5176		goto out;
5177	}
5178
5179	if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
5180		struct mtget mt_status;
5181
5182		if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
5183			 retval = (-EINVAL);
5184			 goto out;
5185		}
5186
5187		mt_status.mt_type = MT_ISONSTREAM_SC;
5188		mt_status.mt_erreg = STp->recover_erreg << MT_ST_SOFTERR_SHIFT;
5189		mt_status.mt_dsreg =
5190			((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
5191			((STp->density    << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
5192		mt_status.mt_blkno = STps->drv_block;
5193		mt_status.mt_fileno = STps->drv_file;
5194		if (STp->block_size != 0) {
5195			if (STps->rw == ST_WRITING)
5196				mt_status.mt_blkno += (STp->buffer)->buffer_bytes / STp->block_size;
5197			else if (STps->rw == ST_READING)
5198				mt_status.mt_blkno -= ((STp->buffer)->buffer_bytes +
5199							STp->block_size - 1) / STp->block_size;
5200		}
5201
5202		mt_status.mt_gstat = 0;
5203		if (STp->drv_write_prot)
5204			mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
5205		if (mt_status.mt_blkno == 0) {
5206			if (mt_status.mt_fileno == 0)
5207				mt_status.mt_gstat |= GMT_BOT(0xffffffff);
5208			else
5209				mt_status.mt_gstat |= GMT_EOF(0xffffffff);
5210		}
5211		mt_status.mt_resid = STp->partition;
5212		if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
5213			mt_status.mt_gstat |= GMT_EOT(0xffffffff);
5214		else if (STps->eof >= ST_EOM_OK)
5215			mt_status.mt_gstat |= GMT_EOD(0xffffffff);
5216		if (STp->density == 1)
5217			mt_status.mt_gstat |= GMT_D_800(0xffffffff);
5218		else if (STp->density == 2)
5219			mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
5220		else if (STp->density == 3)
5221			mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
5222		if (STp->ready == ST_READY)
5223			mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
5224		if (STp->ready == ST_NO_TAPE)
5225			mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
5226		if (STps->at_sm)
5227			mt_status.mt_gstat |= GMT_SM(0xffffffff);
5228		if (STm->do_async_writes || (STm->do_buffer_writes && STp->block_size != 0) ||
5229		    STp->drv_buffer != 0)
5230			mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
5231
5232		i = copy_to_user(p, &mt_status, sizeof(struct mtget));
5233		if (i) {
5234			retval = (-EFAULT);
5235			goto out;
5236		}
5237
5238		STp->recover_erreg = 0;  /* Clear after read */
5239		retval = 0;
5240		goto out;
5241	} /* End of MTIOCGET */
5242
5243	if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
5244		struct mtpos mt_pos;
5245
5246		if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
5247			retval = (-EINVAL);
5248			goto out;
5249		}
5250		if (STp->raw)
5251			blk = osst_get_frame_position(STp, &SRpnt);
5252		else
5253			blk = osst_get_sector(STp, &SRpnt);
5254		if (blk < 0) {
5255			retval = blk;
5256			goto out;
5257		}
5258		mt_pos.mt_blkno = blk;
5259		i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
5260		if (i)
5261			retval = -EFAULT;
5262		goto out;
5263	}
5264	if (SRpnt) osst_release_request(SRpnt);
5265
5266	mutex_unlock(&STp->lock);
5267
5268	retval = scsi_ioctl(STp->device, cmd_in, p);
5269	mutex_unlock(&osst_int_mutex);
5270	return retval;
5271
5272out:
5273	if (SRpnt) osst_release_request(SRpnt);
5274
5275	mutex_unlock(&STp->lock);
5276	mutex_unlock(&osst_int_mutex);
5277
5278	return retval;
5279}
5280
5281#ifdef CONFIG_COMPAT
5282static long osst_compat_ioctl(struct file * file, unsigned int cmd_in, unsigned long arg)
5283{
5284	struct osst_tape *STp = file->private_data;
5285	struct scsi_device *sdev = STp->device;
5286	int ret = -ENOIOCTLCMD;
5287	if (sdev->host->hostt->compat_ioctl) {
5288
5289		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
5290
5291	}
5292	return ret;
5293}
5294#endif
5295
5296
5297
5298/* Memory handling routines */
5299
5300/* Try to allocate a new tape buffer skeleton. Caller must not hold os_scsi_tapes_lock */
5301static struct osst_buffer * new_tape_buffer( int from_initialization, int need_dma, int max_sg )
5302{
5303	int i;
5304	gfp_t priority;
5305	struct osst_buffer *tb;
5306
5307	if (from_initialization)
5308		priority = GFP_ATOMIC;
5309	else
5310		priority = GFP_KERNEL;
5311
5312	i = sizeof(struct osst_buffer) + (osst_max_sg_segs - 1) * sizeof(struct scatterlist);
5313	tb = kzalloc(i, priority);
5314	if (!tb) {
5315		printk(KERN_NOTICE "osst :I: Can't allocate new tape buffer.\n");
5316		return NULL;
5317	}
5318
5319	tb->sg_segs = tb->orig_sg_segs = 0;
5320	tb->use_sg = max_sg;
5321	tb->in_use = 1;
5322	tb->dma = need_dma;
5323	tb->buffer_size = 0;
5324#if DEBUG
5325	if (debugging) 
5326		printk(OSST_DEB_MSG
5327			"osst :D: Allocated tape buffer skeleton (%d bytes, %d segments, dma: %d).\n",
5328			   i, max_sg, need_dma);
5329#endif
5330	return tb;
5331}
5332
5333/* Try to allocate a temporary (while a user has the device open) enlarged tape buffer */
5334static int enlarge_buffer(struct osst_buffer *STbuffer, int need_dma)
5335{
5336	int segs, nbr, max_segs, b_size, order, got;
5337	gfp_t priority;
5338
5339	if (STbuffer->buffer_size >= OS_FRAME_SIZE)
5340		return 1;
5341
5342	if (STbuffer->sg_segs) {
5343		printk(KERN_WARNING "osst :A: Buffer not previously normalized.\n");
5344		normalize_buffer(STbuffer);
5345	}
5346	/* See how many segments we can use -- need at least two */
5347	nbr = max_segs = STbuffer->use_sg;
5348	if (nbr <= 2)
5349		return 0;
5350
5351	priority = GFP_KERNEL /* | __GFP_NOWARN */;
5352	if (need_dma)
5353		priority |= GFP_DMA;
5354
5355	/* Try to allocate the first segment up to OS_DATA_SIZE and the others
5356	   big enough to reach the goal (code assumes no segments in place) */
5357	for (b_size = OS_DATA_SIZE, order = OSST_FIRST_ORDER; b_size >= PAGE_SIZE; order--, b_size /= 2) {
5358		struct page *page = alloc_pages(priority, order);
5359
5360		STbuffer->sg[0].offset = 0;
5361		if (page != NULL) {
5362		    sg_set_page(&STbuffer->sg[0], page, b_size, 0);
5363		    STbuffer->b_data = page_address(page);
5364		    break;
5365		}
5366	}
5367	if (sg_page(&STbuffer->sg[0]) == NULL) {
5368		printk(KERN_NOTICE "osst :I: Can't allocate tape buffer main segment.\n");
5369		return 0;
5370	}
5371	/* Got initial segment of 'bsize,order', continue with same size if possible, except for AUX */
5372	for (segs=STbuffer->sg_segs=1, got=b_size;
5373	     segs < max_segs && got < OS_FRAME_SIZE; ) {
5374		struct page *page = alloc_pages(priority, (OS_FRAME_SIZE - got <= PAGE_SIZE) ? 0 : order);
5375		STbuffer->sg[segs].offset = 0;
5376		if (page == NULL) {
5377			printk(KERN_WARNING "osst :W: Failed to enlarge buffer to %d bytes.\n",
5378						OS_FRAME_SIZE);
5379#if DEBUG
5380			STbuffer->buffer_size = got;
5381#endif
5382			normalize_buffer(STbuffer);
5383			return 0;
5384		}
5385		sg_set_page(&STbuffer->sg[segs], page, (OS_FRAME_SIZE - got <= PAGE_SIZE / 2) ? (OS_FRAME_SIZE - got) : b_size, 0);
5386		got += STbuffer->sg[segs].length;
5387		STbuffer->buffer_size = got;
5388		STbuffer->sg_segs = ++segs;
5389	}
5390#if DEBUG
5391	if (debugging) {
5392		printk(OSST_DEB_MSG
5393			   "osst :D: Expanded tape buffer (%d bytes, %d->%d segments, dma: %d, at: %p).\n",
5394			   got, STbuffer->orig_sg_segs, STbuffer->sg_segs, need_dma, STbuffer->b_data);
5395		printk(OSST_DEB_MSG
5396			   "osst :D: segment sizes: first %d at %p, last %d bytes at %p.\n",
5397			   STbuffer->sg[0].length, page_address(STbuffer->sg[0].page),
5398			   STbuffer->sg[segs-1].length, page_address(STbuffer->sg[segs-1].page));
5399	}
5400#endif
5401
5402	return 1;
5403}
5404
5405
5406/* Release the segments */
5407static void normalize_buffer(struct osst_buffer *STbuffer)
5408{
5409  int i, order, b_size;
5410
5411	for (i=0; i < STbuffer->sg_segs; i++) {
5412
5413		for (b_size = PAGE_SIZE, order = 0;
5414		     b_size < STbuffer->sg[i].length;
5415		     b_size *= 2, order++);
5416
5417		__free_pages(sg_page(&STbuffer->sg[i]), order);
5418		STbuffer->buffer_size -= STbuffer->sg[i].length;
5419	}
5420#if DEBUG
5421	if (debugging && STbuffer->orig_sg_segs < STbuffer->sg_segs)
5422		printk(OSST_DEB_MSG "osst :D: Buffer at %p normalized to %d bytes (segs %d).\n",
5423			     STbuffer->b_data, STbuffer->buffer_size, STbuffer->sg_segs);
5424#endif
5425	STbuffer->sg_segs = STbuffer->orig_sg_segs = 0;
5426}
5427
5428
5429/* Move data from the user buffer to the tape buffer. Returns zero (success) or
5430   negative error code. */
5431static int append_to_buffer(const char __user *ubp, struct osst_buffer *st_bp, int do_count)
5432{
5433	int i, cnt, res, offset;
5434
5435	for (i=0, offset=st_bp->buffer_bytes;
5436	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5437		offset -= st_bp->sg[i].length;
5438	if (i == st_bp->sg_segs) {  /* Should never happen */
5439		printk(KERN_WARNING "osst :A: Append_to_buffer offset overflow.\n");
5440		return (-EIO);
5441	}
5442	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {
5443		cnt = st_bp->sg[i].length - offset < do_count ?
5444		      st_bp->sg[i].length - offset : do_count;
5445		res = copy_from_user(page_address(sg_page(&st_bp->sg[i])) + offset, ubp, cnt);
5446		if (res)
5447			return (-EFAULT);
5448		do_count -= cnt;
5449		st_bp->buffer_bytes += cnt;
5450		ubp += cnt;
5451		offset = 0;
5452	}
5453	if (do_count) {  /* Should never happen */
5454		printk(KERN_WARNING "osst :A: Append_to_buffer overflow (left %d).\n",
5455		       do_count);
5456		return (-EIO);
5457	}
5458	return 0;
5459}
5460
5461
5462/* Move data from the tape buffer to the user buffer. Returns zero (success) or
5463   negative error code. */
5464static int from_buffer(struct osst_buffer *st_bp, char __user *ubp, int do_count)
5465{
5466	int i, cnt, res, offset;
5467
5468	for (i=0, offset=st_bp->read_pointer;
5469	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5470		offset -= st_bp->sg[i].length;
5471	if (i == st_bp->sg_segs) {  /* Should never happen */
5472		printk(KERN_WARNING "osst :A: From_buffer offset overflow.\n");
5473		return (-EIO);
5474	}
5475	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {
5476		cnt = st_bp->sg[i].length - offset < do_count ?
5477		      st_bp->sg[i].length - offset : do_count;
5478		res = copy_to_user(ubp, page_address(sg_page(&st_bp->sg[i])) + offset, cnt);
5479		if (res)
5480			return (-EFAULT);
5481		do_count -= cnt;
5482		st_bp->buffer_bytes -= cnt;
5483		st_bp->read_pointer += cnt;
5484		ubp += cnt;
5485		offset = 0;
5486	}
5487	if (do_count) {  /* Should never happen */
5488		printk(KERN_WARNING "osst :A: From_buffer overflow (left %d).\n", do_count);
5489		return (-EIO);
5490	}
5491	return 0;
5492}
5493
5494/* Sets the tail of the buffer after fill point to zero.
5495   Returns zero (success) or negative error code.        */
5496static int osst_zero_buffer_tail(struct osst_buffer *st_bp)
5497{
5498	int	i, offset, do_count, cnt;
5499
5500	for (i = 0, offset = st_bp->buffer_bytes;
5501	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5502		offset -= st_bp->sg[i].length;
5503	if (i == st_bp->sg_segs) {  /* Should never happen */
5504		printk(KERN_WARNING "osst :A: Zero_buffer offset overflow.\n");
5505		return (-EIO);
5506	}
5507	for (do_count = OS_DATA_SIZE - st_bp->buffer_bytes;
5508	     i < st_bp->sg_segs && do_count > 0; i++) {
5509		cnt = st_bp->sg[i].length - offset < do_count ?
5510		      st_bp->sg[i].length - offset : do_count ;
5511		memset(page_address(sg_page(&st_bp->sg[i])) + offset, 0, cnt);
5512		do_count -= cnt;
5513		offset = 0;
5514	}
5515	if (do_count) {  /* Should never happen */
5516		printk(KERN_WARNING "osst :A: Zero_buffer overflow (left %d).\n", do_count);
5517		return (-EIO);
5518	}
5519	return 0;
5520}
5521
5522/* Copy a osst 32K chunk of memory into the buffer.
5523   Returns zero (success) or negative error code.  */
5524static int osst_copy_to_buffer(struct osst_buffer *st_bp, unsigned char *ptr)
5525{
5526	int	i, cnt, do_count = OS_DATA_SIZE;
5527
5528	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {
5529		cnt = st_bp->sg[i].length < do_count ?
5530		      st_bp->sg[i].length : do_count ;
5531		memcpy(page_address(sg_page(&st_bp->sg[i])), ptr, cnt);
5532		do_count -= cnt;
5533		ptr      += cnt;
5534	}
5535	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */
5536		printk(KERN_WARNING "osst :A: Copy_to_buffer overflow (left %d at sg %d).\n",
5537					 do_count, i);
5538		return (-EIO);
5539	}
5540	return 0;
5541}
5542
5543/* Copy a osst 32K chunk of memory from the buffer.
5544   Returns zero (success) or negative error code.  */
5545static int osst_copy_from_buffer(struct osst_buffer *st_bp, unsigned char *ptr)
5546{
5547	int	i, cnt, do_count = OS_DATA_SIZE;
5548
5549	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {
5550		cnt = st_bp->sg[i].length < do_count ?
5551		      st_bp->sg[i].length : do_count ;
5552		memcpy(ptr, page_address(sg_page(&st_bp->sg[i])), cnt);
5553		do_count -= cnt;
5554		ptr      += cnt;
5555	}
5556	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */
5557		printk(KERN_WARNING "osst :A: Copy_from_buffer overflow (left %d at sg %d).\n",
5558					 do_count, i);
5559		return (-EIO);
5560	}
5561	return 0;
5562}
5563
5564
5565/* Module housekeeping */
5566
5567static void validate_options (void)
5568{
5569  if (max_dev > 0)
5570		osst_max_dev = max_dev;  
5571  if (write_threshold_kbs > 0)
5572		osst_write_threshold = write_threshold_kbs * ST_KILOBYTE;
5573  if (osst_write_threshold > osst_buffer_size)
5574		osst_write_threshold = osst_buffer_size;
5575  if (max_sg_segs >= OSST_FIRST_SG)
5576		osst_max_sg_segs = max_sg_segs;
5577#if DEBUG
5578  printk(OSST_DEB_MSG "osst :D: max tapes %d, write threshold %d, max s/g segs %d.\n",
5579			   osst_max_dev, osst_write_threshold, osst_max_sg_segs);
5580#endif
5581}
5582	
5583#ifndef MODULE
5584/* Set the boot options. Syntax: osst=xxx,yyy,...
5585   where xxx is write threshold in 1024 byte blocks,
5586   and   yyy is number of s/g segments to use. */
5587static int __init osst_setup (char *str)
5588{
5589  int i, ints[5];
5590  char *stp;
5591
5592  stp = get_options(str, ARRAY_SIZE(ints), ints);
5593
5594  if (ints[0] > 0) {
5595	for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
5596		  *parms[i].val = ints[i + 1];
5597  } else {
5598	while (stp != NULL) {
5599		for (i = 0; i < ARRAY_SIZE(parms); i++) {
5600			int len = strlen(parms[i].name);
5601			if (!strncmp(stp, parms[i].name, len) &&
5602			    (*(stp + len) == ':' || *(stp + len) == '=')) {
5603				*parms[i].val =
5604					simple_strtoul(stp + len + 1, NULL, 0);
5605				break;
5606			}
5607		}
5608		if (i >= ARRAY_SIZE(parms))
5609			printk(KERN_INFO "osst :I: Illegal parameter in '%s'\n",
5610			       stp);
5611		stp = strchr(stp, ',');
5612		if (stp)
5613			stp++;
5614	}
5615  }
5616
5617  return 1;
5618}
5619
5620__setup("osst=", osst_setup);
5621
5622#endif
5623
5624static const struct file_operations osst_fops = {
5625	.owner =        THIS_MODULE,
5626	.read =         osst_read,
5627	.write =        osst_write,
5628	.unlocked_ioctl = osst_ioctl,
5629#ifdef CONFIG_COMPAT
5630	.compat_ioctl = osst_compat_ioctl,
5631#endif
5632	.open =         os_scsi_tape_open,
5633	.flush =        os_scsi_tape_flush,
5634	.release =      os_scsi_tape_close,
5635	.llseek =	noop_llseek,
5636};
5637
5638static int osst_supports(struct scsi_device * SDp)
5639{
5640	struct	osst_support_data {
5641		char *vendor;
5642		char *model;
5643		char *rev;
5644		char *driver_hint; /* Name of the correct driver, NULL if unknown */
5645	};
5646
5647static	struct	osst_support_data support_list[] = {
5648		/* {"XXX", "Yy-", "", NULL},  example */
5649		SIGS_FROM_OSST,
5650		{NULL, }};
5651
5652	struct	osst_support_data *rp;
5653
5654	/* We are willing to drive OnStream SC-x0 as well as the
5655	 * 	 * IDE, ParPort, FireWire, USB variants, if accessible by
5656	 * 	 	 * emulation layer (ide-scsi, usb-storage, ...) */
5657
5658	for (rp=&(support_list[0]); rp->vendor != NULL; rp++)
5659		if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
5660		    !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
5661		    !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) 
5662			return 1;
5663	return 0;
5664}
5665
5666/*
5667 * sysfs support for osst driver parameter information
5668 */
5669
5670static ssize_t version_show(struct device_driver *ddd, char *buf)
5671{
5672	return snprintf(buf, PAGE_SIZE, "%s\n", osst_version);
5673}
5674
5675static DRIVER_ATTR_RO(version);
5676
5677static int osst_create_sysfs_files(struct device_driver *sysfs)
5678{
5679	return driver_create_file(sysfs, &driver_attr_version);
5680}
5681
5682static void osst_remove_sysfs_files(struct device_driver *sysfs)
5683{
5684	driver_remove_file(sysfs, &driver_attr_version);
5685}
5686
5687/*
5688 * sysfs support for accessing ADR header information
5689 */
5690
5691static ssize_t osst_adr_rev_show(struct device *dev,
5692				 struct device_attribute *attr, char *buf)
5693{
5694	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5695	ssize_t l = 0;
5696
5697	if (STp && STp->header_ok && STp->linux_media)
5698		l = snprintf(buf, PAGE_SIZE, "%d.%d\n", STp->header_cache->major_rev, STp->header_cache->minor_rev);
5699	return l;
5700}
5701
5702DEVICE_ATTR(ADR_rev, S_IRUGO, osst_adr_rev_show, NULL);
5703
5704static ssize_t osst_linux_media_version_show(struct device *dev,
5705					     struct device_attribute *attr,
5706					     char *buf)
5707{
5708	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5709	ssize_t l = 0;
5710
5711	if (STp && STp->header_ok && STp->linux_media)
5712		l = snprintf(buf, PAGE_SIZE, "LIN%d\n", STp->linux_media_version);
5713	return l;
5714}
5715
5716DEVICE_ATTR(media_version, S_IRUGO, osst_linux_media_version_show, NULL);
5717
5718static ssize_t osst_capacity_show(struct device *dev,
5719				  struct device_attribute *attr, char *buf)
5720{
5721	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5722	ssize_t l = 0;
5723
5724	if (STp && STp->header_ok && STp->linux_media)
5725		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->capacity);
5726	return l;
5727}
5728
5729DEVICE_ATTR(capacity, S_IRUGO, osst_capacity_show, NULL);
5730
5731static ssize_t osst_first_data_ppos_show(struct device *dev,
5732					 struct device_attribute *attr,
5733					 char *buf)
5734{
5735	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5736	ssize_t l = 0;
5737
5738	if (STp && STp->header_ok && STp->linux_media)
5739		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->first_data_ppos);
5740	return l;
5741}
5742
5743DEVICE_ATTR(BOT_frame, S_IRUGO, osst_first_data_ppos_show, NULL);
5744
5745static ssize_t osst_eod_frame_ppos_show(struct device *dev,
5746					struct device_attribute *attr,
5747					char *buf)
5748{
5749	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5750	ssize_t l = 0;
5751
5752	if (STp && STp->header_ok && STp->linux_media)
5753		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->eod_frame_ppos);
5754	return l;
5755}
5756
5757DEVICE_ATTR(EOD_frame, S_IRUGO, osst_eod_frame_ppos_show, NULL);
5758
5759static ssize_t osst_filemark_cnt_show(struct device *dev,
5760				      struct device_attribute *attr, char *buf)
5761{
5762	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5763	ssize_t l = 0;
5764
5765	if (STp && STp->header_ok && STp->linux_media)
5766		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->filemark_cnt);
5767	return l;
5768}
5769
5770DEVICE_ATTR(file_count, S_IRUGO, osst_filemark_cnt_show, NULL);
5771
5772static struct class *osst_sysfs_class;
5773
5774static int osst_sysfs_init(void)
5775{
5776	osst_sysfs_class = class_create(THIS_MODULE, "onstream_tape");
5777	if (IS_ERR(osst_sysfs_class)) {
5778		printk(KERN_ERR "osst :W: Unable to register sysfs class\n");
5779		return PTR_ERR(osst_sysfs_class);
5780	}
5781
5782	return 0;
5783}
5784
5785static void osst_sysfs_destroy(dev_t dev)
5786{
5787	device_destroy(osst_sysfs_class, dev);
5788}
5789
5790static int osst_sysfs_add(dev_t dev, struct device *device, struct osst_tape * STp, char * name)
5791{
5792	struct device *osst_member;
5793	int err;
5794
5795	osst_member = device_create(osst_sysfs_class, device, dev, STp,
5796				    "%s", name);
5797	if (IS_ERR(osst_member)) {
5798		printk(KERN_WARNING "osst :W: Unable to add sysfs class member %s\n", name);
5799		return PTR_ERR(osst_member);
5800	}
5801
5802	err = device_create_file(osst_member, &dev_attr_ADR_rev);
5803	if (err)
5804		goto err_out;
5805	err = device_create_file(osst_member, &dev_attr_media_version);
5806	if (err)
5807		goto err_out;
5808	err = device_create_file(osst_member, &dev_attr_capacity);
5809	if (err)
5810		goto err_out;
5811	err = device_create_file(osst_member, &dev_attr_BOT_frame);
5812	if (err)
5813		goto err_out;
5814	err = device_create_file(osst_member, &dev_attr_EOD_frame);
5815	if (err)
5816		goto err_out;
5817	err = device_create_file(osst_member, &dev_attr_file_count);
5818	if (err)
5819		goto err_out;
5820
5821	return 0;
5822
5823err_out:
5824	osst_sysfs_destroy(dev);
5825	return err;
5826}
5827
5828static void osst_sysfs_cleanup(void)
5829{
5830	class_destroy(osst_sysfs_class);
5831}
5832
5833/*
5834 * osst startup / cleanup code
5835 */
5836
5837static int osst_probe(struct device *dev)
5838{
5839	struct scsi_device * SDp = to_scsi_device(dev);
5840	struct osst_tape   * tpnt;
5841	struct st_modedef  * STm;
5842	struct st_partstat * STps;
5843	struct osst_buffer * buffer;
5844	struct gendisk	   * drive;
5845	int		     i, dev_num, err = -ENODEV;
5846
5847	if (SDp->type != TYPE_TAPE || !osst_supports(SDp))
5848		return -ENODEV;
5849
5850	drive = alloc_disk(1);
5851	if (!drive) {
5852		printk(KERN_ERR "osst :E: Out of memory. Device not attached.\n");
5853		return -ENODEV;
5854	}
5855
5856	/* if this is the first attach, build the infrastructure */
5857	write_lock(&os_scsi_tapes_lock);
5858	if (os_scsi_tapes == NULL) {
5859		os_scsi_tapes = kmalloc(osst_max_dev * sizeof(struct osst_tape *), GFP_ATOMIC);
5860		if (os_scsi_tapes == NULL) {
5861			write_unlock(&os_scsi_tapes_lock);
5862			printk(KERN_ERR "osst :E: Unable to allocate array for OnStream SCSI tapes.\n");
5863			goto out_put_disk;
5864		}
5865		for (i=0; i < osst_max_dev; ++i) os_scsi_tapes[i] = NULL;
5866	}
5867	
5868	if (osst_nr_dev >= osst_max_dev) {
5869		write_unlock(&os_scsi_tapes_lock);
5870		printk(KERN_ERR "osst :E: Too many tape devices (max. %d).\n", osst_max_dev);
5871		goto out_put_disk;
5872	}
5873
5874	/* find a free minor number */
5875	for (i = 0; i < osst_max_dev && os_scsi_tapes[i]; i++)
5876		;
5877	if(i >= osst_max_dev) panic ("Scsi_devices corrupt (osst)");
5878	dev_num = i;
5879
5880	/* allocate a struct osst_tape for this device */
5881	tpnt = kzalloc(sizeof(struct osst_tape), GFP_ATOMIC);
5882	if (!tpnt) {
5883		write_unlock(&os_scsi_tapes_lock);
5884		printk(KERN_ERR "osst :E: Can't allocate device descriptor, device not attached.\n");
5885		goto out_put_disk;
5886	}
5887
5888	/* allocate a buffer for this device */
5889	i = SDp->host->sg_tablesize;
5890	if (osst_max_sg_segs < i)
5891		i = osst_max_sg_segs;
5892	buffer = new_tape_buffer(1, SDp->host->unchecked_isa_dma, i);
5893	if (buffer == NULL) {
5894		write_unlock(&os_scsi_tapes_lock);
5895		printk(KERN_ERR "osst :E: Unable to allocate a tape buffer, device not attached.\n");
5896		kfree(tpnt);
5897		goto out_put_disk;
5898	}
5899	os_scsi_tapes[dev_num] = tpnt;
5900	tpnt->buffer = buffer;
5901	tpnt->device = SDp;
5902	drive->private_data = &tpnt->driver;
5903	sprintf(drive->disk_name, "osst%d", dev_num);
5904	tpnt->driver = &osst_template;
5905	tpnt->drive = drive;
5906	tpnt->in_use = 0;
5907	tpnt->capacity = 0xfffff;
5908	tpnt->dirty = 0;
5909	tpnt->drv_buffer = 1;  /* Try buffering if no mode sense */
5910	tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
5911	tpnt->density = 0;
5912	tpnt->do_auto_lock = OSST_AUTO_LOCK;
5913	tpnt->can_bsr = OSST_IN_FILE_POS;
5914	tpnt->can_partitions = 0;
5915	tpnt->two_fm = OSST_TWO_FM;
5916	tpnt->fast_mteom = OSST_FAST_MTEOM;
5917	tpnt->scsi2_logical = OSST_SCSI2LOGICAL; /* FIXME */
5918	tpnt->write_threshold = osst_write_threshold;
5919	tpnt->default_drvbuffer = 0xff; /* No forced buffering */
5920	tpnt->partition = 0;
5921	tpnt->new_partition = 0;
5922	tpnt->nbr_partitions = 0;
5923	tpnt->min_block = 512;
5924	tpnt->max_block = OS_DATA_SIZE;
5925	tpnt->timeout = OSST_TIMEOUT;
5926	tpnt->long_timeout = OSST_LONG_TIMEOUT;
5927
5928	/* Recognize OnStream tapes */
5929	/* We don't need to test for OnStream, as this has been done in detect () */
5930	tpnt->os_fw_rev = osst_parse_firmware_rev (SDp->rev);
5931	tpnt->omit_blklims = 1;
5932
5933	tpnt->poll = (strncmp(SDp->model, "DI-", 3) == 0) || 
5934		     (strncmp(SDp->model, "FW-", 3) == 0) || OSST_FW_NEED_POLL(tpnt->os_fw_rev,SDp);
5935	tpnt->frame_in_buffer = 0;
5936	tpnt->header_ok = 0;
5937	tpnt->linux_media = 0;
5938	tpnt->header_cache = NULL;
5939
5940	for (i=0; i < ST_NBR_MODES; i++) {
5941		STm = &(tpnt->modes[i]);
5942		STm->defined = 0;
5943		STm->sysv = OSST_SYSV;
5944		STm->defaults_for_writes = 0;
5945		STm->do_async_writes = OSST_ASYNC_WRITES;
5946		STm->do_buffer_writes = OSST_BUFFER_WRITES;
5947		STm->do_read_ahead = OSST_READ_AHEAD;
5948		STm->default_compression = ST_DONT_TOUCH;
5949		STm->default_blksize = 512;
5950		STm->default_density = (-1);  /* No forced density */
5951	}
5952
5953	for (i=0; i < ST_NBR_PARTITIONS; i++) {
5954		STps = &(tpnt->ps[i]);
5955		STps->rw = ST_IDLE;
5956		STps->eof = ST_NOEOF;
5957		STps->at_sm = 0;
5958		STps->last_block_valid = 0;
5959		STps->drv_block = (-1);
5960		STps->drv_file = (-1);
5961	}
5962
5963	tpnt->current_mode = 0;
5964	tpnt->modes[0].defined = 1;
5965	tpnt->modes[2].defined = 1;
5966	tpnt->density_changed = tpnt->compression_changed = tpnt->blksize_changed = 0;
5967
5968	mutex_init(&tpnt->lock);
5969	osst_nr_dev++;
5970	write_unlock(&os_scsi_tapes_lock);
5971
5972	{
5973		char name[8];
5974
5975		/*  Rewind entry  */
5976		err = osst_sysfs_add(MKDEV(OSST_MAJOR, dev_num), dev, tpnt, tape_name(tpnt));
5977		if (err)
5978			goto out_free_buffer;
5979
5980		/*  No-rewind entry  */
5981		snprintf(name, 8, "%s%s", "n", tape_name(tpnt));
5982		err = osst_sysfs_add(MKDEV(OSST_MAJOR, dev_num + 128), dev, tpnt, name);
5983		if (err)
5984			goto out_free_sysfs1;
5985	}
5986
5987	sdev_printk(KERN_INFO, SDp,
5988		"osst :I: Attached OnStream %.5s tape as %s\n",
5989		SDp->model, tape_name(tpnt));
5990
5991	return 0;
5992
5993out_free_sysfs1:
5994	osst_sysfs_destroy(MKDEV(OSST_MAJOR, dev_num));
5995out_free_buffer:
5996	kfree(buffer);
5997out_put_disk:
5998        put_disk(drive);
5999        return err;
6000};
6001
6002static int osst_remove(struct device *dev)
6003{
6004	struct scsi_device * SDp = to_scsi_device(dev);
6005	struct osst_tape * tpnt;
6006	int i;
6007
6008	if ((SDp->type != TYPE_TAPE) || (osst_nr_dev <= 0))
6009		return 0;
6010
6011	write_lock(&os_scsi_tapes_lock);
6012	for(i=0; i < osst_max_dev; i++) {
6013		if((tpnt = os_scsi_tapes[i]) && (tpnt->device == SDp)) {
6014			osst_sysfs_destroy(MKDEV(OSST_MAJOR, i));
6015			osst_sysfs_destroy(MKDEV(OSST_MAJOR, i+128));
6016			tpnt->device = NULL;
6017			put_disk(tpnt->drive);
6018			os_scsi_tapes[i] = NULL;
6019			osst_nr_dev--;
6020			write_unlock(&os_scsi_tapes_lock);
6021			vfree(tpnt->header_cache);
6022			if (tpnt->buffer) {
6023				normalize_buffer(tpnt->buffer);
6024				kfree(tpnt->buffer);
6025			}
6026			kfree(tpnt);
6027			return 0;
6028		}
6029	}
6030	write_unlock(&os_scsi_tapes_lock);
6031	return 0;
6032}
6033
6034static int __init init_osst(void) 
6035{
6036	int err;
6037
6038	printk(KERN_INFO "osst :I: Tape driver with OnStream support version %s\nosst :I: %s\n", osst_version, cvsid);
6039
6040	validate_options();
6041
6042	err = osst_sysfs_init();
6043	if (err)
6044		return err;
6045
6046	err = register_chrdev(OSST_MAJOR, "osst", &osst_fops);
6047	if (err < 0) {
6048		printk(KERN_ERR "osst :E: Unable to register major %d for OnStream tapes\n", OSST_MAJOR);
6049		goto err_out;
6050	}
6051
6052	err = scsi_register_driver(&osst_template.gendrv);
6053	if (err)
6054		goto err_out_chrdev;
6055
6056	err = osst_create_sysfs_files(&osst_template.gendrv);
6057	if (err)
6058		goto err_out_scsidrv;
6059
6060	return 0;
6061
6062err_out_scsidrv:
6063	scsi_unregister_driver(&osst_template.gendrv);
6064err_out_chrdev:
6065	unregister_chrdev(OSST_MAJOR, "osst");
6066err_out:
6067	osst_sysfs_cleanup();
6068	return err;
6069}
6070
6071static void __exit exit_osst (void)
6072{
6073	int i;
6074	struct osst_tape * STp;
6075
6076	osst_remove_sysfs_files(&osst_template.gendrv);
6077	scsi_unregister_driver(&osst_template.gendrv);
6078	unregister_chrdev(OSST_MAJOR, "osst");
6079	osst_sysfs_cleanup();
6080
6081	if (os_scsi_tapes) {
6082		for (i=0; i < osst_max_dev; ++i) {
6083			if (!(STp = os_scsi_tapes[i])) continue;
6084			/* This is defensive, supposed to happen during detach */
6085			vfree(STp->header_cache);
6086			if (STp->buffer) {
6087				normalize_buffer(STp->buffer);
6088				kfree(STp->buffer);
6089			}
6090			put_disk(STp->drive);
6091			kfree(STp);
6092		}
6093		kfree(os_scsi_tapes);
6094	}
6095	printk(KERN_INFO "osst :I: Unloaded.\n");
6096}
6097
6098module_init(init_osst);
6099module_exit(exit_osst);