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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
4 file Documentation/scsi/st.rst for more information.
5
6 History:
7 Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
8 Contribution and ideas from several people including (in alphabetical
9 order) Klaus Ehrenfried, Eugene Exarevsky, Eric Lee Green, Wolfgang Denk,
10 Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
11 Michael Schaefer, J"org Weule, and Eric Youngdale.
12
13 Copyright 1992 - 2016 Kai Makisara
14 email Kai.Makisara@kolumbus.fi
15
16 Some small formal changes - aeb, 950809
17
18 Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
19 */
20
21static const char *verstr = "20160209";
22
23#include <linux/module.h>
24
25#include <linux/compat.h>
26#include <linux/fs.h>
27#include <linux/kernel.h>
28#include <linux/sched/signal.h>
29#include <linux/mm.h>
30#include <linux/init.h>
31#include <linux/string.h>
32#include <linux/slab.h>
33#include <linux/errno.h>
34#include <linux/mtio.h>
35#include <linux/major.h>
36#include <linux/cdrom.h>
37#include <linux/ioctl.h>
38#include <linux/fcntl.h>
39#include <linux/spinlock.h>
40#include <linux/blkdev.h>
41#include <linux/moduleparam.h>
42#include <linux/cdev.h>
43#include <linux/idr.h>
44#include <linux/delay.h>
45#include <linux/mutex.h>
46
47#include <linux/uaccess.h>
48#include <asm/dma.h>
49#include <asm/unaligned.h>
50
51#include <scsi/scsi.h>
52#include <scsi/scsi_dbg.h>
53#include <scsi/scsi_device.h>
54#include <scsi/scsi_driver.h>
55#include <scsi/scsi_eh.h>
56#include <scsi/scsi_host.h>
57#include <scsi/scsi_ioctl.h>
58#include <scsi/sg.h>
59
60
61/* The driver prints some debugging information on the console if DEBUG
62 is defined and non-zero. */
63#define DEBUG 1
64#define NO_DEBUG 0
65
66#define ST_DEB_MSG KERN_NOTICE
67#if DEBUG
68/* The message level for the debug messages is currently set to KERN_NOTICE
69 so that people can easily see the messages. Later when the debugging messages
70 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
71#define DEB(a) a
72#define DEBC(a) if (debugging) { a ; }
73#else
74#define DEB(a)
75#define DEBC(a)
76#endif
77
78#define ST_KILOBYTE 1024
79
80#include "st_options.h"
81#include "st.h"
82
83static int buffer_kbs;
84static int max_sg_segs;
85static int try_direct_io = TRY_DIRECT_IO;
86static int try_rdio = 1;
87static int try_wdio = 1;
88static int debug_flag;
89
90static struct class st_sysfs_class;
91static const struct attribute_group *st_dev_groups[];
92static const struct attribute_group *st_drv_groups[];
93
94MODULE_AUTHOR("Kai Makisara");
95MODULE_DESCRIPTION("SCSI tape (st) driver");
96MODULE_LICENSE("GPL");
97MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
98MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
99
100/* Set 'perm' (4th argument) to 0 to disable module_param's definition
101 * of sysfs parameters (which module_param doesn't yet support).
102 * Sysfs parameters defined explicitly later.
103 */
104module_param_named(buffer_kbs, buffer_kbs, int, 0);
105MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
106module_param_named(max_sg_segs, max_sg_segs, int, 0);
107MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
108module_param_named(try_direct_io, try_direct_io, int, 0);
109MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
110module_param_named(debug_flag, debug_flag, int, 0);
111MODULE_PARM_DESC(debug_flag, "Enable DEBUG, same as setting debugging=1");
112
113
114/* Extra parameters for testing */
115module_param_named(try_rdio, try_rdio, int, 0);
116MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
117module_param_named(try_wdio, try_wdio, int, 0);
118MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
119
120#ifndef MODULE
121static int write_threshold_kbs; /* retained for compatibility */
122static struct st_dev_parm {
123 char *name;
124 int *val;
125} parms[] __initdata = {
126 {
127 "buffer_kbs", &buffer_kbs
128 },
129 { /* Retained for compatibility with 2.4 */
130 "write_threshold_kbs", &write_threshold_kbs
131 },
132 {
133 "max_sg_segs", NULL
134 },
135 {
136 "try_direct_io", &try_direct_io
137 },
138 {
139 "debug_flag", &debug_flag
140 }
141};
142#endif
143
144/* Restrict the number of modes so that names for all are assigned */
145#if ST_NBR_MODES > 16
146#error "Maximum number of modes is 16"
147#endif
148/* Bit reversed order to get same names for same minors with all
149 mode counts */
150static const char *st_formats[] = {
151 "", "r", "k", "s", "l", "t", "o", "u",
152 "m", "v", "p", "x", "a", "y", "q", "z"};
153
154/* The default definitions have been moved to st_options.h */
155
156#define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
157
158/* The buffer size should fit into the 24 bits for length in the
159 6-byte SCSI read and write commands. */
160#if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
161#error "Buffer size should not exceed (2 << 24 - 1) bytes!"
162#endif
163
164static int debugging = DEBUG;
165
166#define MAX_RETRIES 0
167#define MAX_WRITE_RETRIES 0
168#define MAX_READY_RETRIES 0
169#define NO_TAPE NOT_READY
170
171#define ST_TIMEOUT (900 * HZ)
172#define ST_LONG_TIMEOUT (14000 * HZ)
173
174/* Remove mode bits and auto-rewind bit (7) */
175#define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
176 (iminor(x) & ((1 << ST_MODE_SHIFT)-1)))
177#define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
178
179/* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
180#define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
181 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
182
183/* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
184 24 bits) */
185#define SET_DENS_AND_BLK 0x10001
186
187static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
188static int st_max_sg_segs = ST_MAX_SG;
189
190static int modes_defined;
191
192static int enlarge_buffer(struct st_buffer *, int);
193static void clear_buffer(struct st_buffer *);
194static void normalize_buffer(struct st_buffer *);
195static int append_to_buffer(const char __user *, struct st_buffer *, int);
196static int from_buffer(struct st_buffer *, char __user *, int);
197static void move_buffer_data(struct st_buffer *, int);
198
199static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
200 unsigned long, size_t, int);
201static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
202
203static int st_probe(struct device *);
204static int st_remove(struct device *);
205
206static struct scsi_driver st_template = {
207 .gendrv = {
208 .name = "st",
209 .owner = THIS_MODULE,
210 .probe = st_probe,
211 .remove = st_remove,
212 .groups = st_drv_groups,
213 },
214};
215
216static int st_compression(struct scsi_tape *, int);
217
218static int find_partition(struct scsi_tape *);
219static int switch_partition(struct scsi_tape *);
220
221static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
222
223static void scsi_tape_release(struct kref *);
224
225#define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
226
227static DEFINE_MUTEX(st_ref_mutex);
228static DEFINE_SPINLOCK(st_index_lock);
229static DEFINE_SPINLOCK(st_use_lock);
230static DEFINE_IDR(st_index_idr);
231
232
233
234#ifndef SIGS_FROM_OSST
235#define SIGS_FROM_OSST \
236 {"OnStream", "SC-", "", "osst"}, \
237 {"OnStream", "DI-", "", "osst"}, \
238 {"OnStream", "DP-", "", "osst"}, \
239 {"OnStream", "USB", "", "osst"}, \
240 {"OnStream", "FW-", "", "osst"}
241#endif
242
243static struct scsi_tape *scsi_tape_get(int dev)
244{
245 struct scsi_tape *STp = NULL;
246
247 mutex_lock(&st_ref_mutex);
248 spin_lock(&st_index_lock);
249
250 STp = idr_find(&st_index_idr, dev);
251 if (!STp) goto out;
252
253 kref_get(&STp->kref);
254
255 if (!STp->device)
256 goto out_put;
257
258 if (scsi_device_get(STp->device))
259 goto out_put;
260
261 goto out;
262
263out_put:
264 kref_put(&STp->kref, scsi_tape_release);
265 STp = NULL;
266out:
267 spin_unlock(&st_index_lock);
268 mutex_unlock(&st_ref_mutex);
269 return STp;
270}
271
272static void scsi_tape_put(struct scsi_tape *STp)
273{
274 struct scsi_device *sdev = STp->device;
275
276 mutex_lock(&st_ref_mutex);
277 kref_put(&STp->kref, scsi_tape_release);
278 scsi_device_put(sdev);
279 mutex_unlock(&st_ref_mutex);
280}
281
282struct st_reject_data {
283 char *vendor;
284 char *model;
285 char *rev;
286 char *driver_hint; /* Name of the correct driver, NULL if unknown */
287};
288
289static struct st_reject_data reject_list[] = {
290 /* {"XXX", "Yy-", "", NULL}, example */
291 SIGS_FROM_OSST,
292 {NULL, }};
293
294/* If the device signature is on the list of incompatible drives, the
295 function returns a pointer to the name of the correct driver (if known) */
296static char * st_incompatible(struct scsi_device* SDp)
297{
298 struct st_reject_data *rp;
299
300 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
301 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
302 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
303 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
304 if (rp->driver_hint)
305 return rp->driver_hint;
306 else
307 return "unknown";
308 }
309 return NULL;
310}
311
312
313#define st_printk(prefix, t, fmt, a...) \
314 sdev_prefix_printk(prefix, (t)->device, (t)->name, fmt, ##a)
315#ifdef DEBUG
316#define DEBC_printk(t, fmt, a...) \
317 if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }
318#else
319#define DEBC_printk(t, fmt, a...)
320#endif
321
322static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
323{
324 const u8 *ucp;
325 const u8 *sense = SRpnt->sense;
326
327 s->have_sense = scsi_normalize_sense(SRpnt->sense,
328 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
329 s->flags = 0;
330
331 if (s->have_sense) {
332 s->deferred = 0;
333 s->remainder_valid =
334 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
335 switch (sense[0] & 0x7f) {
336 case 0x71:
337 s->deferred = 1;
338 fallthrough;
339 case 0x70:
340 s->fixed_format = 1;
341 s->flags = sense[2] & 0xe0;
342 break;
343 case 0x73:
344 s->deferred = 1;
345 fallthrough;
346 case 0x72:
347 s->fixed_format = 0;
348 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
349 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
350 break;
351 }
352 }
353}
354
355
356/* Convert the result to success code */
357static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
358{
359 int result = SRpnt->result;
360 u8 scode;
361 DEB(const char *stp;)
362 char *name = STp->name;
363 struct st_cmdstatus *cmdstatp;
364
365 if (!result)
366 return 0;
367
368 cmdstatp = &STp->buffer->cmdstat;
369 st_analyze_sense(SRpnt, cmdstatp);
370
371 if (cmdstatp->have_sense)
372 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
373 else
374 scode = 0;
375
376 DEB(
377 if (debugging) {
378 st_printk(ST_DEB_MSG, STp,
379 "Error: %x, cmd: %x %x %x %x %x %x\n", result,
380 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
381 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
382 if (cmdstatp->have_sense)
383 __scsi_print_sense(STp->device, name,
384 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
385 } ) /* end DEB */
386 if (!debugging) { /* Abnormal conditions for tape */
387 if (!cmdstatp->have_sense)
388 st_printk(KERN_WARNING, STp,
389 "Error %x (driver bt 0, host bt 0x%x).\n",
390 result, host_byte(result));
391 else if (cmdstatp->have_sense &&
392 scode != NO_SENSE &&
393 scode != RECOVERED_ERROR &&
394 /* scode != UNIT_ATTENTION && */
395 scode != BLANK_CHECK &&
396 scode != VOLUME_OVERFLOW &&
397 SRpnt->cmd[0] != MODE_SENSE &&
398 SRpnt->cmd[0] != TEST_UNIT_READY) {
399
400 __scsi_print_sense(STp->device, name,
401 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
402 }
403 }
404
405 if (cmdstatp->fixed_format &&
406 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
407 if (STp->cln_sense_value)
408 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
409 STp->cln_sense_mask) == STp->cln_sense_value);
410 else
411 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
412 STp->cln_sense_mask) != 0);
413 }
414 if (cmdstatp->have_sense &&
415 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
416 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
417 if (cmdstatp->have_sense && scode == UNIT_ATTENTION && cmdstatp->sense_hdr.asc == 0x29)
418 STp->pos_unknown = 1; /* ASC => power on / reset */
419
420 STp->pos_unknown |= STp->device->was_reset;
421
422 if (cmdstatp->have_sense &&
423 scode == RECOVERED_ERROR
424#if ST_RECOVERED_WRITE_FATAL
425 && SRpnt->cmd[0] != WRITE_6
426 && SRpnt->cmd[0] != WRITE_FILEMARKS
427#endif
428 ) {
429 STp->recover_count++;
430 STp->recover_reg++;
431
432 DEB(
433 if (debugging) {
434 if (SRpnt->cmd[0] == READ_6)
435 stp = "read";
436 else if (SRpnt->cmd[0] == WRITE_6)
437 stp = "write";
438 else
439 stp = "ioctl";
440 st_printk(ST_DEB_MSG, STp,
441 "Recovered %s error (%d).\n",
442 stp, STp->recover_count);
443 } ) /* end DEB */
444
445 if (cmdstatp->flags == 0)
446 return 0;
447 }
448 return (-EIO);
449}
450
451static struct st_request *st_allocate_request(struct scsi_tape *stp)
452{
453 struct st_request *streq;
454
455 streq = kzalloc(sizeof(*streq), GFP_KERNEL);
456 if (streq)
457 streq->stp = stp;
458 else {
459 st_printk(KERN_ERR, stp,
460 "Can't get SCSI request.\n");
461 if (signal_pending(current))
462 stp->buffer->syscall_result = -EINTR;
463 else
464 stp->buffer->syscall_result = -EBUSY;
465 }
466
467 return streq;
468}
469
470static void st_release_request(struct st_request *streq)
471{
472 kfree(streq);
473}
474
475static void st_do_stats(struct scsi_tape *STp, struct request *req)
476{
477 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
478 ktime_t now;
479
480 now = ktime_get();
481 if (scmd->cmnd[0] == WRITE_6) {
482 now = ktime_sub(now, STp->stats->write_time);
483 atomic64_add(ktime_to_ns(now), &STp->stats->tot_write_time);
484 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
485 atomic64_inc(&STp->stats->write_cnt);
486 if (scmd->result) {
487 atomic64_add(atomic_read(&STp->stats->last_write_size)
488 - STp->buffer->cmdstat.residual,
489 &STp->stats->write_byte_cnt);
490 if (STp->buffer->cmdstat.residual > 0)
491 atomic64_inc(&STp->stats->resid_cnt);
492 } else
493 atomic64_add(atomic_read(&STp->stats->last_write_size),
494 &STp->stats->write_byte_cnt);
495 } else if (scmd->cmnd[0] == READ_6) {
496 now = ktime_sub(now, STp->stats->read_time);
497 atomic64_add(ktime_to_ns(now), &STp->stats->tot_read_time);
498 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
499 atomic64_inc(&STp->stats->read_cnt);
500 if (scmd->result) {
501 atomic64_add(atomic_read(&STp->stats->last_read_size)
502 - STp->buffer->cmdstat.residual,
503 &STp->stats->read_byte_cnt);
504 if (STp->buffer->cmdstat.residual > 0)
505 atomic64_inc(&STp->stats->resid_cnt);
506 } else
507 atomic64_add(atomic_read(&STp->stats->last_read_size),
508 &STp->stats->read_byte_cnt);
509 } else {
510 now = ktime_sub(now, STp->stats->other_time);
511 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
512 atomic64_inc(&STp->stats->other_cnt);
513 }
514 atomic64_dec(&STp->stats->in_flight);
515}
516
517static enum rq_end_io_ret st_scsi_execute_end(struct request *req,
518 blk_status_t status)
519{
520 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
521 struct st_request *SRpnt = req->end_io_data;
522 struct scsi_tape *STp = SRpnt->stp;
523 struct bio *tmp;
524
525 STp->buffer->cmdstat.midlevel_result = SRpnt->result = scmd->result;
526 STp->buffer->cmdstat.residual = scmd->resid_len;
527
528 st_do_stats(STp, req);
529
530 tmp = SRpnt->bio;
531 if (scmd->sense_len)
532 memcpy(SRpnt->sense, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
533 if (SRpnt->waiting)
534 complete(SRpnt->waiting);
535
536 blk_rq_unmap_user(tmp);
537 blk_mq_free_request(req);
538 return RQ_END_IO_NONE;
539}
540
541static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
542 int data_direction, void *buffer, unsigned bufflen,
543 int timeout, int retries)
544{
545 struct request *req;
546 struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
547 int err = 0;
548 struct scsi_tape *STp = SRpnt->stp;
549 struct scsi_cmnd *scmd;
550
551 req = scsi_alloc_request(SRpnt->stp->device->request_queue,
552 data_direction == DMA_TO_DEVICE ?
553 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
554 if (IS_ERR(req))
555 return PTR_ERR(req);
556 scmd = blk_mq_rq_to_pdu(req);
557 req->rq_flags |= RQF_QUIET;
558
559 mdata->null_mapped = 1;
560
561 if (bufflen) {
562 err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
563 GFP_KERNEL);
564 if (err) {
565 blk_mq_free_request(req);
566 return err;
567 }
568 }
569
570 atomic64_inc(&STp->stats->in_flight);
571 if (cmd[0] == WRITE_6) {
572 atomic_set(&STp->stats->last_write_size, bufflen);
573 STp->stats->write_time = ktime_get();
574 } else if (cmd[0] == READ_6) {
575 atomic_set(&STp->stats->last_read_size, bufflen);
576 STp->stats->read_time = ktime_get();
577 } else {
578 STp->stats->other_time = ktime_get();
579 }
580
581 SRpnt->bio = req->bio;
582 scmd->cmd_len = COMMAND_SIZE(cmd[0]);
583 memcpy(scmd->cmnd, cmd, scmd->cmd_len);
584 req->timeout = timeout;
585 scmd->allowed = retries;
586 req->end_io = st_scsi_execute_end;
587 req->end_io_data = SRpnt;
588
589 blk_execute_rq_nowait(req, true);
590 return 0;
591}
592
593/* Do the scsi command. Waits until command performed if do_wait is true.
594 Otherwise write_behind_check() is used to check that the command
595 has finished. */
596static struct st_request *
597st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
598 int bytes, int direction, int timeout, int retries, int do_wait)
599{
600 struct completion *waiting;
601 struct rq_map_data *mdata = &STp->buffer->map_data;
602 int ret;
603
604 /* if async, make sure there's no command outstanding */
605 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
606 st_printk(KERN_ERR, STp,
607 "Async command already active.\n");
608 if (signal_pending(current))
609 (STp->buffer)->syscall_result = (-EINTR);
610 else
611 (STp->buffer)->syscall_result = (-EBUSY);
612 return NULL;
613 }
614
615 if (!SRpnt) {
616 SRpnt = st_allocate_request(STp);
617 if (!SRpnt)
618 return NULL;
619 }
620
621 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
622 which IO is outstanding. It's nulled out when the IO completes. */
623 if (!do_wait)
624 (STp->buffer)->last_SRpnt = SRpnt;
625
626 waiting = &STp->wait;
627 init_completion(waiting);
628 SRpnt->waiting = waiting;
629
630 if (STp->buffer->do_dio) {
631 mdata->page_order = 0;
632 mdata->nr_entries = STp->buffer->sg_segs;
633 mdata->pages = STp->buffer->mapped_pages;
634 } else {
635 mdata->page_order = STp->buffer->reserved_page_order;
636 mdata->nr_entries =
637 DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
638 mdata->pages = STp->buffer->reserved_pages;
639 mdata->offset = 0;
640 }
641
642 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
643 STp->buffer->cmdstat.have_sense = 0;
644 STp->buffer->syscall_result = 0;
645
646 ret = st_scsi_execute(SRpnt, cmd, direction, NULL, bytes, timeout,
647 retries);
648 if (ret) {
649 /* could not allocate the buffer or request was too large */
650 (STp->buffer)->syscall_result = (-EBUSY);
651 (STp->buffer)->last_SRpnt = NULL;
652 } else if (do_wait) {
653 wait_for_completion(waiting);
654 SRpnt->waiting = NULL;
655 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
656 }
657
658 return SRpnt;
659}
660
661
662/* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
663 write has been correct but EOM early warning reached, -EIO if write ended in
664 error or zero if write successful. Asynchronous writes are used only in
665 variable block mode. */
666static int write_behind_check(struct scsi_tape * STp)
667{
668 int retval = 0;
669 struct st_buffer *STbuffer;
670 struct st_partstat *STps;
671 struct st_cmdstatus *cmdstatp;
672 struct st_request *SRpnt;
673
674 STbuffer = STp->buffer;
675 if (!STbuffer->writing)
676 return 0;
677
678 DEB(
679 if (STp->write_pending)
680 STp->nbr_waits++;
681 else
682 STp->nbr_finished++;
683 ) /* end DEB */
684
685 wait_for_completion(&(STp->wait));
686 SRpnt = STbuffer->last_SRpnt;
687 STbuffer->last_SRpnt = NULL;
688 SRpnt->waiting = NULL;
689
690 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
691 st_release_request(SRpnt);
692
693 STbuffer->buffer_bytes -= STbuffer->writing;
694 STps = &(STp->ps[STp->partition]);
695 if (STps->drv_block >= 0) {
696 if (STp->block_size == 0)
697 STps->drv_block++;
698 else
699 STps->drv_block += STbuffer->writing / STp->block_size;
700 }
701
702 cmdstatp = &STbuffer->cmdstat;
703 if (STbuffer->syscall_result) {
704 retval = -EIO;
705 if (cmdstatp->have_sense && !cmdstatp->deferred &&
706 (cmdstatp->flags & SENSE_EOM) &&
707 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
708 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
709 /* EOM at write-behind, has all data been written? */
710 if (!cmdstatp->remainder_valid ||
711 cmdstatp->uremainder64 == 0)
712 retval = -ENOSPC;
713 }
714 if (retval == -EIO)
715 STps->drv_block = -1;
716 }
717 STbuffer->writing = 0;
718
719 DEB(if (debugging && retval)
720 st_printk(ST_DEB_MSG, STp,
721 "Async write error %x, return value %d.\n",
722 STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
723
724 return retval;
725}
726
727
728/* Step over EOF if it has been inadvertently crossed (ioctl not used because
729 it messes up the block number). */
730static int cross_eof(struct scsi_tape * STp, int forward)
731{
732 struct st_request *SRpnt;
733 unsigned char cmd[MAX_COMMAND_SIZE];
734
735 cmd[0] = SPACE;
736 cmd[1] = 0x01; /* Space FileMarks */
737 if (forward) {
738 cmd[2] = cmd[3] = 0;
739 cmd[4] = 1;
740 } else
741 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
742 cmd[5] = 0;
743
744 DEBC_printk(STp, "Stepping over filemark %s.\n",
745 forward ? "forward" : "backward");
746
747 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
748 STp->device->request_queue->rq_timeout,
749 MAX_RETRIES, 1);
750 if (!SRpnt)
751 return (STp->buffer)->syscall_result;
752
753 st_release_request(SRpnt);
754 SRpnt = NULL;
755
756 if ((STp->buffer)->cmdstat.midlevel_result != 0)
757 st_printk(KERN_ERR, STp,
758 "Stepping over filemark %s failed.\n",
759 forward ? "forward" : "backward");
760
761 return (STp->buffer)->syscall_result;
762}
763
764
765/* Flush the write buffer (never need to write if variable blocksize). */
766static int st_flush_write_buffer(struct scsi_tape * STp)
767{
768 int transfer, blks;
769 int result;
770 unsigned char cmd[MAX_COMMAND_SIZE];
771 struct st_request *SRpnt;
772 struct st_partstat *STps;
773
774 result = write_behind_check(STp);
775 if (result)
776 return result;
777
778 result = 0;
779 if (STp->dirty == 1) {
780
781 transfer = STp->buffer->buffer_bytes;
782 DEBC_printk(STp, "Flushing %d bytes.\n", transfer);
783
784 memset(cmd, 0, MAX_COMMAND_SIZE);
785 cmd[0] = WRITE_6;
786 cmd[1] = 1;
787 blks = transfer / STp->block_size;
788 cmd[2] = blks >> 16;
789 cmd[3] = blks >> 8;
790 cmd[4] = blks;
791
792 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
793 STp->device->request_queue->rq_timeout,
794 MAX_WRITE_RETRIES, 1);
795 if (!SRpnt)
796 return (STp->buffer)->syscall_result;
797
798 STps = &(STp->ps[STp->partition]);
799 if ((STp->buffer)->syscall_result != 0) {
800 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
801
802 if (cmdstatp->have_sense && !cmdstatp->deferred &&
803 (cmdstatp->flags & SENSE_EOM) &&
804 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
805 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
806 (!cmdstatp->remainder_valid ||
807 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
808 STp->dirty = 0;
809 (STp->buffer)->buffer_bytes = 0;
810 if (STps->drv_block >= 0)
811 STps->drv_block += blks;
812 result = (-ENOSPC);
813 } else {
814 st_printk(KERN_ERR, STp, "Error on flush.\n");
815 STps->drv_block = (-1);
816 result = (-EIO);
817 }
818 } else {
819 if (STps->drv_block >= 0)
820 STps->drv_block += blks;
821 STp->dirty = 0;
822 (STp->buffer)->buffer_bytes = 0;
823 }
824 st_release_request(SRpnt);
825 SRpnt = NULL;
826 }
827 return result;
828}
829
830
831/* Flush the tape buffer. The tape will be positioned correctly unless
832 seek_next is true. */
833static int flush_buffer(struct scsi_tape *STp, int seek_next)
834{
835 int backspace, result;
836 struct st_partstat *STps;
837
838 /*
839 * If there was a bus reset, block further access
840 * to this device.
841 */
842 if (STp->pos_unknown)
843 return (-EIO);
844
845 if (STp->ready != ST_READY)
846 return 0;
847 STps = &(STp->ps[STp->partition]);
848 if (STps->rw == ST_WRITING) /* Writing */
849 return st_flush_write_buffer(STp);
850
851 if (STp->block_size == 0)
852 return 0;
853
854 backspace = ((STp->buffer)->buffer_bytes +
855 (STp->buffer)->read_pointer) / STp->block_size -
856 ((STp->buffer)->read_pointer + STp->block_size - 1) /
857 STp->block_size;
858 (STp->buffer)->buffer_bytes = 0;
859 (STp->buffer)->read_pointer = 0;
860 result = 0;
861 if (!seek_next) {
862 if (STps->eof == ST_FM_HIT) {
863 result = cross_eof(STp, 0); /* Back over the EOF hit */
864 if (!result)
865 STps->eof = ST_NOEOF;
866 else {
867 if (STps->drv_file >= 0)
868 STps->drv_file++;
869 STps->drv_block = 0;
870 }
871 }
872 if (!result && backspace > 0)
873 result = st_int_ioctl(STp, MTBSR, backspace);
874 } else if (STps->eof == ST_FM_HIT) {
875 if (STps->drv_file >= 0)
876 STps->drv_file++;
877 STps->drv_block = 0;
878 STps->eof = ST_NOEOF;
879 }
880 return result;
881
882}
883
884/* Set the mode parameters */
885static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
886{
887 int set_it = 0;
888 unsigned long arg;
889
890 if (!STp->density_changed &&
891 STm->default_density >= 0 &&
892 STm->default_density != STp->density) {
893 arg = STm->default_density;
894 set_it = 1;
895 } else
896 arg = STp->density;
897 arg <<= MT_ST_DENSITY_SHIFT;
898 if (!STp->blksize_changed &&
899 STm->default_blksize >= 0 &&
900 STm->default_blksize != STp->block_size) {
901 arg |= STm->default_blksize;
902 set_it = 1;
903 } else
904 arg |= STp->block_size;
905 if (set_it &&
906 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
907 st_printk(KERN_WARNING, STp,
908 "Can't set default block size to %d bytes "
909 "and density %x.\n",
910 STm->default_blksize, STm->default_density);
911 if (modes_defined)
912 return (-EINVAL);
913 }
914 return 0;
915}
916
917
918/* Lock or unlock the drive door. Don't use when st_request allocated. */
919static int do_door_lock(struct scsi_tape * STp, int do_lock)
920{
921 int retval;
922
923 DEBC_printk(STp, "%socking drive door.\n", do_lock ? "L" : "Unl");
924
925 retval = scsi_set_medium_removal(STp->device,
926 do_lock ? SCSI_REMOVAL_PREVENT : SCSI_REMOVAL_ALLOW);
927 if (!retval)
928 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
929 else
930 STp->door_locked = ST_LOCK_FAILS;
931 return retval;
932}
933
934
935/* Set the internal state after reset */
936static void reset_state(struct scsi_tape *STp)
937{
938 int i;
939 struct st_partstat *STps;
940
941 STp->pos_unknown = 0;
942 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
943 STps = &(STp->ps[i]);
944 STps->rw = ST_IDLE;
945 STps->eof = ST_NOEOF;
946 STps->at_sm = 0;
947 STps->last_block_valid = 0;
948 STps->drv_block = -1;
949 STps->drv_file = -1;
950 }
951 if (STp->can_partitions) {
952 STp->partition = find_partition(STp);
953 if (STp->partition < 0)
954 STp->partition = 0;
955 STp->new_partition = STp->partition;
956 }
957}
958
959/* Test if the drive is ready. Returns either one of the codes below or a negative system
960 error code. */
961#define CHKRES_READY 0
962#define CHKRES_NEW_SESSION 1
963#define CHKRES_NOT_READY 2
964#define CHKRES_NO_TAPE 3
965
966#define MAX_ATTENTIONS 10
967
968static int test_ready(struct scsi_tape *STp, int do_wait)
969{
970 int attentions, waits, max_wait, scode;
971 int retval = CHKRES_READY, new_session = 0;
972 unsigned char cmd[MAX_COMMAND_SIZE];
973 struct st_request *SRpnt = NULL;
974 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
975
976 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
977
978 for (attentions=waits=0; ; ) {
979 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
980 cmd[0] = TEST_UNIT_READY;
981 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
982 STp->long_timeout, MAX_READY_RETRIES, 1);
983
984 if (!SRpnt) {
985 retval = (STp->buffer)->syscall_result;
986 break;
987 }
988
989 if (cmdstatp->have_sense) {
990
991 scode = cmdstatp->sense_hdr.sense_key;
992
993 if (scode == UNIT_ATTENTION) { /* New media? */
994 new_session = 1;
995 if (attentions < MAX_ATTENTIONS) {
996 attentions++;
997 continue;
998 }
999 else {
1000 retval = (-EIO);
1001 break;
1002 }
1003 }
1004
1005 if (scode == NOT_READY) {
1006 if (waits < max_wait) {
1007 if (msleep_interruptible(1000)) {
1008 retval = (-EINTR);
1009 break;
1010 }
1011 waits++;
1012 continue;
1013 }
1014 else {
1015 if ((STp->device)->scsi_level >= SCSI_2 &&
1016 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
1017 retval = CHKRES_NO_TAPE;
1018 else
1019 retval = CHKRES_NOT_READY;
1020 break;
1021 }
1022 }
1023 }
1024
1025 retval = (STp->buffer)->syscall_result;
1026 if (!retval)
1027 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
1028 break;
1029 }
1030
1031 if (SRpnt != NULL)
1032 st_release_request(SRpnt);
1033 return retval;
1034}
1035
1036
1037/* See if the drive is ready and gather information about the tape. Return values:
1038 < 0 negative error code from errno.h
1039 0 drive ready
1040 1 drive not ready (possibly no tape)
1041*/
1042static int check_tape(struct scsi_tape *STp, struct file *filp)
1043{
1044 int i, retval, new_session = 0, do_wait;
1045 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
1046 unsigned short st_flags = filp->f_flags;
1047 struct st_request *SRpnt = NULL;
1048 struct st_modedef *STm;
1049 struct st_partstat *STps;
1050 struct inode *inode = file_inode(filp);
1051 int mode = TAPE_MODE(inode);
1052
1053 STp->ready = ST_READY;
1054
1055 if (mode != STp->current_mode) {
1056 DEBC_printk(STp, "Mode change from %d to %d.\n",
1057 STp->current_mode, mode);
1058 new_session = 1;
1059 STp->current_mode = mode;
1060 }
1061 STm = &(STp->modes[STp->current_mode]);
1062
1063 saved_cleaning = STp->cleaning_req;
1064 STp->cleaning_req = 0;
1065
1066 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
1067 retval = test_ready(STp, do_wait);
1068
1069 if (retval < 0)
1070 goto err_out;
1071
1072 if (retval == CHKRES_NEW_SESSION) {
1073 STp->pos_unknown = 0;
1074 STp->partition = STp->new_partition = 0;
1075 if (STp->can_partitions)
1076 STp->nbr_partitions = 1; /* This guess will be updated later
1077 if necessary */
1078 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1079 STps = &(STp->ps[i]);
1080 STps->rw = ST_IDLE;
1081 STps->eof = ST_NOEOF;
1082 STps->at_sm = 0;
1083 STps->last_block_valid = 0;
1084 STps->drv_block = 0;
1085 STps->drv_file = 0;
1086 }
1087 new_session = 1;
1088 }
1089 else {
1090 STp->cleaning_req |= saved_cleaning;
1091
1092 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
1093 if (retval == CHKRES_NO_TAPE)
1094 STp->ready = ST_NO_TAPE;
1095 else
1096 STp->ready = ST_NOT_READY;
1097
1098 STp->density = 0; /* Clear the erroneous "residue" */
1099 STp->write_prot = 0;
1100 STp->block_size = 0;
1101 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
1102 STp->partition = STp->new_partition = 0;
1103 STp->door_locked = ST_UNLOCKED;
1104 return CHKRES_NOT_READY;
1105 }
1106 }
1107
1108 if (STp->omit_blklims)
1109 STp->min_block = STp->max_block = (-1);
1110 else {
1111 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1112 cmd[0] = READ_BLOCK_LIMITS;
1113
1114 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
1115 STp->device->request_queue->rq_timeout,
1116 MAX_READY_RETRIES, 1);
1117 if (!SRpnt) {
1118 retval = (STp->buffer)->syscall_result;
1119 goto err_out;
1120 }
1121
1122 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1123 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
1124 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1125 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1126 (STp->buffer)->b_data[5];
1127 if ( DEB( debugging || ) !STp->inited)
1128 st_printk(KERN_INFO, STp,
1129 "Block limits %d - %d bytes.\n",
1130 STp->min_block, STp->max_block);
1131 } else {
1132 STp->min_block = STp->max_block = (-1);
1133 DEBC_printk(STp, "Can't read block limits.\n");
1134 }
1135 }
1136
1137 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1138 cmd[0] = MODE_SENSE;
1139 cmd[4] = 12;
1140
1141 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1142 STp->device->request_queue->rq_timeout,
1143 MAX_READY_RETRIES, 1);
1144 if (!SRpnt) {
1145 retval = (STp->buffer)->syscall_result;
1146 goto err_out;
1147 }
1148
1149 if ((STp->buffer)->syscall_result != 0) {
1150 DEBC_printk(STp, "No Mode Sense.\n");
1151 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1152 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1153 STp->drv_write_prot = 0;
1154 } else {
1155 DEBC_printk(STp,"Mode sense. Length %d, "
1156 "medium %x, WBS %x, BLL %d\n",
1157 (STp->buffer)->b_data[0],
1158 (STp->buffer)->b_data[1],
1159 (STp->buffer)->b_data[2],
1160 (STp->buffer)->b_data[3]);
1161
1162 if ((STp->buffer)->b_data[3] >= 8) {
1163 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1164 STp->density = (STp->buffer)->b_data[4];
1165 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1166 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1167 DEBC_printk(STp, "Density %x, tape length: %x, "
1168 "drv buffer: %d\n",
1169 STp->density,
1170 (STp->buffer)->b_data[5] * 65536 +
1171 (STp->buffer)->b_data[6] * 256 +
1172 (STp->buffer)->b_data[7],
1173 STp->drv_buffer);
1174 }
1175 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1176 if (!STp->drv_buffer && STp->immediate_filemark) {
1177 st_printk(KERN_WARNING, STp,
1178 "non-buffered tape: disabling "
1179 "writing immediate filemarks\n");
1180 STp->immediate_filemark = 0;
1181 }
1182 }
1183 st_release_request(SRpnt);
1184 SRpnt = NULL;
1185 STp->inited = 1;
1186
1187 if (STp->block_size > 0)
1188 (STp->buffer)->buffer_blocks =
1189 (STp->buffer)->buffer_size / STp->block_size;
1190 else
1191 (STp->buffer)->buffer_blocks = 1;
1192 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1193
1194 DEBC_printk(STp, "Block size: %d, buffer size: %d (%d blocks).\n",
1195 STp->block_size, (STp->buffer)->buffer_size,
1196 (STp->buffer)->buffer_blocks);
1197
1198 if (STp->drv_write_prot) {
1199 STp->write_prot = 1;
1200
1201 DEBC_printk(STp, "Write protected\n");
1202
1203 if (do_wait &&
1204 ((st_flags & O_ACCMODE) == O_WRONLY ||
1205 (st_flags & O_ACCMODE) == O_RDWR)) {
1206 retval = (-EROFS);
1207 goto err_out;
1208 }
1209 }
1210
1211 if (STp->can_partitions && STp->nbr_partitions < 1) {
1212 /* This code is reached when the device is opened for the first time
1213 after the driver has been initialized with tape in the drive and the
1214 partition support has been enabled. */
1215 DEBC_printk(STp, "Updating partition number in status.\n");
1216 if ((STp->partition = find_partition(STp)) < 0) {
1217 retval = STp->partition;
1218 goto err_out;
1219 }
1220 STp->new_partition = STp->partition;
1221 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1222 }
1223
1224 if (new_session) { /* Change the drive parameters for the new mode */
1225 STp->density_changed = STp->blksize_changed = 0;
1226 STp->compression_changed = 0;
1227 if (!(STm->defaults_for_writes) &&
1228 (retval = set_mode_densblk(STp, STm)) < 0)
1229 goto err_out;
1230
1231 if (STp->default_drvbuffer != 0xff) {
1232 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1233 st_printk(KERN_WARNING, STp,
1234 "Can't set default drive "
1235 "buffering to %d.\n",
1236 STp->default_drvbuffer);
1237 }
1238 }
1239
1240 return CHKRES_READY;
1241
1242 err_out:
1243 return retval;
1244}
1245
1246
1247 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1248 module count. */
1249static int st_open(struct inode *inode, struct file *filp)
1250{
1251 int i, retval = (-EIO);
1252 int resumed = 0;
1253 struct scsi_tape *STp;
1254 struct st_partstat *STps;
1255 int dev = TAPE_NR(inode);
1256
1257 /*
1258 * We really want to do nonseekable_open(inode, filp); here, but some
1259 * versions of tar incorrectly call lseek on tapes and bail out if that
1260 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1261 */
1262 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1263
1264 if (!(STp = scsi_tape_get(dev))) {
1265 return -ENXIO;
1266 }
1267
1268 filp->private_data = STp;
1269
1270 spin_lock(&st_use_lock);
1271 if (STp->in_use) {
1272 spin_unlock(&st_use_lock);
1273 DEBC_printk(STp, "Device already in use.\n");
1274 scsi_tape_put(STp);
1275 return (-EBUSY);
1276 }
1277
1278 STp->in_use = 1;
1279 spin_unlock(&st_use_lock);
1280 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1281
1282 if (scsi_autopm_get_device(STp->device) < 0) {
1283 retval = -EIO;
1284 goto err_out;
1285 }
1286 resumed = 1;
1287 if (!scsi_block_when_processing_errors(STp->device)) {
1288 retval = (-ENXIO);
1289 goto err_out;
1290 }
1291
1292 /* See that we have at least a one page buffer available */
1293 if (!enlarge_buffer(STp->buffer, PAGE_SIZE)) {
1294 st_printk(KERN_WARNING, STp,
1295 "Can't allocate one page tape buffer.\n");
1296 retval = (-EOVERFLOW);
1297 goto err_out;
1298 }
1299
1300 (STp->buffer)->cleared = 0;
1301 (STp->buffer)->writing = 0;
1302 (STp->buffer)->syscall_result = 0;
1303
1304 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1305
1306 STp->dirty = 0;
1307 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1308 STps = &(STp->ps[i]);
1309 STps->rw = ST_IDLE;
1310 }
1311 STp->try_dio_now = STp->try_dio;
1312 STp->recover_count = 0;
1313 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1314 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
1315
1316 retval = check_tape(STp, filp);
1317 if (retval < 0)
1318 goto err_out;
1319 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1320 retval != CHKRES_READY) {
1321 if (STp->ready == NO_TAPE)
1322 retval = (-ENOMEDIUM);
1323 else
1324 retval = (-EIO);
1325 goto err_out;
1326 }
1327 return 0;
1328
1329 err_out:
1330 normalize_buffer(STp->buffer);
1331 spin_lock(&st_use_lock);
1332 STp->in_use = 0;
1333 spin_unlock(&st_use_lock);
1334 if (resumed)
1335 scsi_autopm_put_device(STp->device);
1336 scsi_tape_put(STp);
1337 return retval;
1338
1339}
1340
1341
1342/* Flush the tape buffer before close */
1343static int st_flush(struct file *filp, fl_owner_t id)
1344{
1345 int result = 0, result2;
1346 unsigned char cmd[MAX_COMMAND_SIZE];
1347 struct st_request *SRpnt;
1348 struct scsi_tape *STp = filp->private_data;
1349 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1350 struct st_partstat *STps = &(STp->ps[STp->partition]);
1351
1352 if (file_count(filp) > 1)
1353 return 0;
1354
1355 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1356 result = st_flush_write_buffer(STp);
1357 if (result != 0 && result != (-ENOSPC))
1358 goto out;
1359 }
1360
1361 if (STp->can_partitions &&
1362 (result2 = switch_partition(STp)) < 0) {
1363 DEBC_printk(STp, "switch_partition at close failed.\n");
1364 if (result == 0)
1365 result = result2;
1366 goto out;
1367 }
1368
1369 DEBC( if (STp->nbr_requests)
1370 st_printk(KERN_DEBUG, STp,
1371 "Number of r/w requests %d, dio used in %d, "
1372 "pages %d.\n", STp->nbr_requests, STp->nbr_dio,
1373 STp->nbr_pages));
1374
1375 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1376 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1377
1378#if DEBUG
1379 DEBC_printk(STp, "Async write waits %d, finished %d.\n",
1380 STp->nbr_waits, STp->nbr_finished);
1381#endif
1382 memset(cmd, 0, MAX_COMMAND_SIZE);
1383 cmd[0] = WRITE_FILEMARKS;
1384 if (STp->immediate_filemark)
1385 cmd[1] = 1;
1386 cmd[4] = 1 + STp->two_fm;
1387
1388 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1389 STp->device->request_queue->rq_timeout,
1390 MAX_WRITE_RETRIES, 1);
1391 if (!SRpnt) {
1392 result = (STp->buffer)->syscall_result;
1393 goto out;
1394 }
1395
1396 if (STp->buffer->syscall_result == 0 ||
1397 (cmdstatp->have_sense && !cmdstatp->deferred &&
1398 (cmdstatp->flags & SENSE_EOM) &&
1399 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1400 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1401 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1402 /* Write successful at EOM */
1403 st_release_request(SRpnt);
1404 SRpnt = NULL;
1405 if (STps->drv_file >= 0)
1406 STps->drv_file++;
1407 STps->drv_block = 0;
1408 if (STp->two_fm)
1409 cross_eof(STp, 0);
1410 STps->eof = ST_FM;
1411 }
1412 else { /* Write error */
1413 st_release_request(SRpnt);
1414 SRpnt = NULL;
1415 st_printk(KERN_ERR, STp,
1416 "Error on write filemark.\n");
1417 if (result == 0)
1418 result = (-EIO);
1419 }
1420
1421 DEBC_printk(STp, "Buffer flushed, %d EOF(s) written\n", cmd[4]);
1422 } else if (!STp->rew_at_close) {
1423 STps = &(STp->ps[STp->partition]);
1424 if (!STm->sysv || STps->rw != ST_READING) {
1425 if (STp->can_bsr)
1426 result = flush_buffer(STp, 0);
1427 else if (STps->eof == ST_FM_HIT) {
1428 result = cross_eof(STp, 0);
1429 if (result) {
1430 if (STps->drv_file >= 0)
1431 STps->drv_file++;
1432 STps->drv_block = 0;
1433 STps->eof = ST_FM;
1434 } else
1435 STps->eof = ST_NOEOF;
1436 }
1437 } else if ((STps->eof == ST_NOEOF &&
1438 !(result = cross_eof(STp, 1))) ||
1439 STps->eof == ST_FM_HIT) {
1440 if (STps->drv_file >= 0)
1441 STps->drv_file++;
1442 STps->drv_block = 0;
1443 STps->eof = ST_FM;
1444 }
1445 }
1446
1447 out:
1448 if (STp->rew_at_close) {
1449 result2 = st_int_ioctl(STp, MTREW, 1);
1450 if (result == 0)
1451 result = result2;
1452 }
1453 return result;
1454}
1455
1456
1457/* Close the device and release it. BKL is not needed: this is the only thread
1458 accessing this tape. */
1459static int st_release(struct inode *inode, struct file *filp)
1460{
1461 struct scsi_tape *STp = filp->private_data;
1462
1463 if (STp->door_locked == ST_LOCKED_AUTO)
1464 do_door_lock(STp, 0);
1465
1466 normalize_buffer(STp->buffer);
1467 spin_lock(&st_use_lock);
1468 STp->in_use = 0;
1469 spin_unlock(&st_use_lock);
1470 scsi_autopm_put_device(STp->device);
1471 scsi_tape_put(STp);
1472
1473 return 0;
1474}
1475
1476/* The checks common to both reading and writing */
1477static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1478{
1479 ssize_t retval = 0;
1480
1481 /*
1482 * If we are in the middle of error recovery, don't let anyone
1483 * else try and use this device. Also, if error recovery fails, it
1484 * may try and take the device offline, in which case all further
1485 * access to the device is prohibited.
1486 */
1487 if (!scsi_block_when_processing_errors(STp->device)) {
1488 retval = (-ENXIO);
1489 goto out;
1490 }
1491
1492 if (STp->ready != ST_READY) {
1493 if (STp->ready == ST_NO_TAPE)
1494 retval = (-ENOMEDIUM);
1495 else
1496 retval = (-EIO);
1497 goto out;
1498 }
1499
1500 if (! STp->modes[STp->current_mode].defined) {
1501 retval = (-ENXIO);
1502 goto out;
1503 }
1504
1505
1506 /*
1507 * If there was a bus reset, block further access
1508 * to this device.
1509 */
1510 if (STp->pos_unknown) {
1511 retval = (-EIO);
1512 goto out;
1513 }
1514
1515 if (count == 0)
1516 goto out;
1517
1518 DEB(
1519 if (!STp->in_use) {
1520 st_printk(ST_DEB_MSG, STp,
1521 "Incorrect device.\n");
1522 retval = (-EIO);
1523 goto out;
1524 } ) /* end DEB */
1525
1526 if (STp->can_partitions &&
1527 (retval = switch_partition(STp)) < 0)
1528 goto out;
1529
1530 if (STp->block_size == 0 && STp->max_block > 0 &&
1531 (count < STp->min_block || count > STp->max_block)) {
1532 retval = (-EINVAL);
1533 goto out;
1534 }
1535
1536 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1537 !do_door_lock(STp, 1))
1538 STp->door_locked = ST_LOCKED_AUTO;
1539
1540 out:
1541 return retval;
1542}
1543
1544
1545static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1546 size_t count, int is_read)
1547{
1548 int i, bufsize, retval = 0;
1549 struct st_buffer *STbp = STp->buffer;
1550
1551 if (is_read)
1552 i = STp->try_dio_now && try_rdio;
1553 else
1554 i = STp->try_dio_now && try_wdio;
1555
1556 if (i && ((unsigned long)buf & queue_dma_alignment(
1557 STp->device->request_queue)) == 0) {
1558 i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
1559 count, (is_read ? READ : WRITE));
1560 if (i > 0) {
1561 STbp->do_dio = i;
1562 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1563 }
1564 else
1565 STbp->do_dio = 0; /* fall back to buffering with any error */
1566 STbp->sg_segs = STbp->do_dio;
1567 DEB(
1568 if (STbp->do_dio) {
1569 STp->nbr_dio++;
1570 STp->nbr_pages += STbp->do_dio;
1571 }
1572 )
1573 } else
1574 STbp->do_dio = 0;
1575 DEB( STp->nbr_requests++; )
1576
1577 if (!STbp->do_dio) {
1578 if (STp->block_size)
1579 bufsize = STp->block_size > st_fixed_buffer_size ?
1580 STp->block_size : st_fixed_buffer_size;
1581 else {
1582 bufsize = count;
1583 /* Make sure that data from previous user is not leaked even if
1584 HBA does not return correct residual */
1585 if (is_read && STp->sili && !STbp->cleared)
1586 clear_buffer(STbp);
1587 }
1588
1589 if (bufsize > STbp->buffer_size &&
1590 !enlarge_buffer(STbp, bufsize)) {
1591 st_printk(KERN_WARNING, STp,
1592 "Can't allocate %d byte tape buffer.\n",
1593 bufsize);
1594 retval = (-EOVERFLOW);
1595 goto out;
1596 }
1597 if (STp->block_size)
1598 STbp->buffer_blocks = bufsize / STp->block_size;
1599 }
1600
1601 out:
1602 return retval;
1603}
1604
1605
1606/* Can be called more than once after each setup_buffer() */
1607static void release_buffering(struct scsi_tape *STp, int is_read)
1608{
1609 struct st_buffer *STbp;
1610
1611 STbp = STp->buffer;
1612 if (STbp->do_dio) {
1613 sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
1614 STbp->do_dio = 0;
1615 STbp->sg_segs = 0;
1616 }
1617}
1618
1619
1620/* Write command */
1621static ssize_t
1622st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1623{
1624 ssize_t total;
1625 ssize_t i, do_count, blks, transfer;
1626 ssize_t retval;
1627 int undone, retry_eot = 0, scode;
1628 int async_write;
1629 unsigned char cmd[MAX_COMMAND_SIZE];
1630 const char __user *b_point;
1631 struct st_request *SRpnt = NULL;
1632 struct scsi_tape *STp = filp->private_data;
1633 struct st_modedef *STm;
1634 struct st_partstat *STps;
1635 struct st_buffer *STbp;
1636
1637 if (mutex_lock_interruptible(&STp->lock))
1638 return -ERESTARTSYS;
1639
1640 retval = rw_checks(STp, filp, count);
1641 if (retval || count == 0)
1642 goto out;
1643
1644 /* Write must be integral number of blocks */
1645 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1646 st_printk(KERN_WARNING, STp,
1647 "Write not multiple of tape block size.\n");
1648 retval = (-EINVAL);
1649 goto out;
1650 }
1651
1652 STm = &(STp->modes[STp->current_mode]);
1653 STps = &(STp->ps[STp->partition]);
1654
1655 if (STp->write_prot) {
1656 retval = (-EACCES);
1657 goto out;
1658 }
1659
1660
1661 if (STps->rw == ST_READING) {
1662 retval = flush_buffer(STp, 0);
1663 if (retval)
1664 goto out;
1665 STps->rw = ST_WRITING;
1666 } else if (STps->rw != ST_WRITING &&
1667 STps->drv_file == 0 && STps->drv_block == 0) {
1668 if ((retval = set_mode_densblk(STp, STm)) < 0)
1669 goto out;
1670 if (STm->default_compression != ST_DONT_TOUCH &&
1671 !(STp->compression_changed)) {
1672 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1673 st_printk(KERN_WARNING, STp,
1674 "Can't set default compression.\n");
1675 if (modes_defined) {
1676 retval = (-EINVAL);
1677 goto out;
1678 }
1679 }
1680 }
1681 }
1682
1683 STbp = STp->buffer;
1684 i = write_behind_check(STp);
1685 if (i) {
1686 if (i == -ENOSPC)
1687 STps->eof = ST_EOM_OK;
1688 else
1689 STps->eof = ST_EOM_ERROR;
1690 }
1691
1692 if (STps->eof == ST_EOM_OK) {
1693 STps->eof = ST_EOD_1; /* allow next write */
1694 retval = (-ENOSPC);
1695 goto out;
1696 }
1697 else if (STps->eof == ST_EOM_ERROR) {
1698 retval = (-EIO);
1699 goto out;
1700 }
1701
1702 /* Check the buffer readability in cases where copy_user might catch
1703 the problems after some tape movement. */
1704 if (STp->block_size != 0 &&
1705 !STbp->do_dio &&
1706 (copy_from_user(&i, buf, 1) != 0 ||
1707 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1708 retval = (-EFAULT);
1709 goto out;
1710 }
1711
1712 retval = setup_buffering(STp, buf, count, 0);
1713 if (retval)
1714 goto out;
1715
1716 total = count;
1717
1718 memset(cmd, 0, MAX_COMMAND_SIZE);
1719 cmd[0] = WRITE_6;
1720 cmd[1] = (STp->block_size != 0);
1721
1722 STps->rw = ST_WRITING;
1723
1724 b_point = buf;
1725 while (count > 0 && !retry_eot) {
1726
1727 if (STbp->do_dio) {
1728 do_count = count;
1729 }
1730 else {
1731 if (STp->block_size == 0)
1732 do_count = count;
1733 else {
1734 do_count = STbp->buffer_blocks * STp->block_size -
1735 STbp->buffer_bytes;
1736 if (do_count > count)
1737 do_count = count;
1738 }
1739
1740 i = append_to_buffer(b_point, STbp, do_count);
1741 if (i) {
1742 retval = i;
1743 goto out;
1744 }
1745 }
1746 count -= do_count;
1747 b_point += do_count;
1748
1749 async_write = STp->block_size == 0 && !STbp->do_dio &&
1750 STm->do_async_writes && STps->eof < ST_EOM_OK;
1751
1752 if (STp->block_size != 0 && STm->do_buffer_writes &&
1753 !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
1754 STbp->buffer_bytes < STbp->buffer_size) {
1755 STp->dirty = 1;
1756 /* Don't write a buffer that is not full enough. */
1757 if (!async_write && count == 0)
1758 break;
1759 }
1760
1761 retry_write:
1762 if (STp->block_size == 0)
1763 blks = transfer = do_count;
1764 else {
1765 if (!STbp->do_dio)
1766 blks = STbp->buffer_bytes;
1767 else
1768 blks = do_count;
1769 blks /= STp->block_size;
1770 transfer = blks * STp->block_size;
1771 }
1772 cmd[2] = blks >> 16;
1773 cmd[3] = blks >> 8;
1774 cmd[4] = blks;
1775
1776 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1777 STp->device->request_queue->rq_timeout,
1778 MAX_WRITE_RETRIES, !async_write);
1779 if (!SRpnt) {
1780 retval = STbp->syscall_result;
1781 goto out;
1782 }
1783 if (async_write && !STbp->syscall_result) {
1784 STbp->writing = transfer;
1785 STp->dirty = !(STbp->writing ==
1786 STbp->buffer_bytes);
1787 SRpnt = NULL; /* Prevent releasing this request! */
1788 DEB( STp->write_pending = 1; )
1789 break;
1790 }
1791
1792 if (STbp->syscall_result != 0) {
1793 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1794
1795 DEBC_printk(STp, "Error on write:\n");
1796 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1797 scode = cmdstatp->sense_hdr.sense_key;
1798 if (cmdstatp->remainder_valid)
1799 undone = (int)cmdstatp->uremainder64;
1800 else if (STp->block_size == 0 &&
1801 scode == VOLUME_OVERFLOW)
1802 undone = transfer;
1803 else
1804 undone = 0;
1805 if (STp->block_size != 0)
1806 undone *= STp->block_size;
1807 if (undone <= do_count) {
1808 /* Only data from this write is not written */
1809 count += undone;
1810 b_point -= undone;
1811 do_count -= undone;
1812 if (STp->block_size)
1813 blks = (transfer - undone) / STp->block_size;
1814 STps->eof = ST_EOM_OK;
1815 /* Continue in fixed block mode if all written
1816 in this request but still something left to write
1817 (retval left to zero)
1818 */
1819 if (STp->block_size == 0 ||
1820 undone > 0 || count == 0)
1821 retval = (-ENOSPC); /* EOM within current request */
1822 DEBC_printk(STp, "EOM with %d "
1823 "bytes unwritten.\n",
1824 (int)count);
1825 } else {
1826 /* EOT within data buffered earlier (possible only
1827 in fixed block mode without direct i/o) */
1828 if (!retry_eot && !cmdstatp->deferred &&
1829 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1830 move_buffer_data(STp->buffer, transfer - undone);
1831 retry_eot = 1;
1832 if (STps->drv_block >= 0) {
1833 STps->drv_block += (transfer - undone) /
1834 STp->block_size;
1835 }
1836 STps->eof = ST_EOM_OK;
1837 DEBC_printk(STp, "Retry "
1838 "write of %d "
1839 "bytes at EOM.\n",
1840 STp->buffer->buffer_bytes);
1841 goto retry_write;
1842 }
1843 else {
1844 /* Either error within data buffered by driver or
1845 failed retry */
1846 count -= do_count;
1847 blks = do_count = 0;
1848 STps->eof = ST_EOM_ERROR;
1849 STps->drv_block = (-1); /* Too cautious? */
1850 retval = (-EIO); /* EOM for old data */
1851 DEBC_printk(STp, "EOM with "
1852 "lost data.\n");
1853 }
1854 }
1855 } else {
1856 count += do_count;
1857 STps->drv_block = (-1); /* Too cautious? */
1858 retval = STbp->syscall_result;
1859 }
1860
1861 }
1862
1863 if (STps->drv_block >= 0) {
1864 if (STp->block_size == 0)
1865 STps->drv_block += (do_count > 0);
1866 else
1867 STps->drv_block += blks;
1868 }
1869
1870 STbp->buffer_bytes = 0;
1871 STp->dirty = 0;
1872
1873 if (retval || retry_eot) {
1874 if (count < total)
1875 retval = total - count;
1876 goto out;
1877 }
1878 }
1879
1880 if (STps->eof == ST_EOD_1)
1881 STps->eof = ST_EOM_OK;
1882 else if (STps->eof != ST_EOM_OK)
1883 STps->eof = ST_NOEOF;
1884 retval = total - count;
1885
1886 out:
1887 if (SRpnt != NULL)
1888 st_release_request(SRpnt);
1889 release_buffering(STp, 0);
1890 mutex_unlock(&STp->lock);
1891
1892 return retval;
1893}
1894
1895/* Read data from the tape. Returns zero in the normal case, one if the
1896 eof status has changed, and the negative error code in case of a
1897 fatal error. Otherwise updates the buffer and the eof state.
1898
1899 Does release user buffer mapping if it is set.
1900*/
1901static long read_tape(struct scsi_tape *STp, long count,
1902 struct st_request ** aSRpnt)
1903{
1904 int transfer, blks, bytes;
1905 unsigned char cmd[MAX_COMMAND_SIZE];
1906 struct st_request *SRpnt;
1907 struct st_modedef *STm;
1908 struct st_partstat *STps;
1909 struct st_buffer *STbp;
1910 int retval = 0;
1911
1912 if (count == 0)
1913 return 0;
1914
1915 STm = &(STp->modes[STp->current_mode]);
1916 STps = &(STp->ps[STp->partition]);
1917 if (STps->eof == ST_FM_HIT)
1918 return 1;
1919 STbp = STp->buffer;
1920
1921 if (STp->block_size == 0)
1922 blks = bytes = count;
1923 else {
1924 if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
1925 blks = (STp->buffer)->buffer_blocks;
1926 bytes = blks * STp->block_size;
1927 } else {
1928 bytes = count;
1929 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1930 bytes = (STp->buffer)->buffer_size;
1931 blks = bytes / STp->block_size;
1932 bytes = blks * STp->block_size;
1933 }
1934 }
1935
1936 memset(cmd, 0, MAX_COMMAND_SIZE);
1937 cmd[0] = READ_6;
1938 cmd[1] = (STp->block_size != 0);
1939 if (!cmd[1] && STp->sili)
1940 cmd[1] |= 2;
1941 cmd[2] = blks >> 16;
1942 cmd[3] = blks >> 8;
1943 cmd[4] = blks;
1944
1945 SRpnt = *aSRpnt;
1946 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1947 STp->device->request_queue->rq_timeout,
1948 MAX_RETRIES, 1);
1949 release_buffering(STp, 1);
1950 *aSRpnt = SRpnt;
1951 if (!SRpnt)
1952 return STbp->syscall_result;
1953
1954 STbp->read_pointer = 0;
1955 STps->at_sm = 0;
1956
1957 /* Something to check */
1958 if (STbp->syscall_result) {
1959 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1960
1961 retval = 1;
1962 DEBC_printk(STp,
1963 "Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1964 SRpnt->sense[0], SRpnt->sense[1],
1965 SRpnt->sense[2], SRpnt->sense[3],
1966 SRpnt->sense[4], SRpnt->sense[5],
1967 SRpnt->sense[6], SRpnt->sense[7]);
1968 if (cmdstatp->have_sense) {
1969
1970 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1971 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1972
1973 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1974 /* Compute the residual count */
1975 if (cmdstatp->remainder_valid)
1976 transfer = (int)cmdstatp->uremainder64;
1977 else
1978 transfer = 0;
1979 if (cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR) {
1980 if (STp->block_size == 0)
1981 transfer = bytes;
1982 /* Some drives set ILI with MEDIUM ERROR */
1983 cmdstatp->flags &= ~SENSE_ILI;
1984 }
1985
1986 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1987 if (STp->block_size == 0 &&
1988 transfer < 0) {
1989 st_printk(KERN_NOTICE, STp,
1990 "Failed to read %d "
1991 "byte block with %d "
1992 "byte transfer.\n",
1993 bytes - transfer,
1994 bytes);
1995 if (STps->drv_block >= 0)
1996 STps->drv_block += 1;
1997 STbp->buffer_bytes = 0;
1998 return (-ENOMEM);
1999 } else if (STp->block_size == 0) {
2000 STbp->buffer_bytes = bytes - transfer;
2001 } else {
2002 st_release_request(SRpnt);
2003 SRpnt = *aSRpnt = NULL;
2004 if (transfer == blks) { /* We did not get anything, error */
2005 st_printk(KERN_NOTICE, STp,
2006 "Incorrect "
2007 "block size.\n");
2008 if (STps->drv_block >= 0)
2009 STps->drv_block += blks - transfer + 1;
2010 st_int_ioctl(STp, MTBSR, 1);
2011 return (-EIO);
2012 }
2013 /* We have some data, deliver it */
2014 STbp->buffer_bytes = (blks - transfer) *
2015 STp->block_size;
2016 DEBC_printk(STp, "ILI but "
2017 "enough data "
2018 "received %ld "
2019 "%d.\n", count,
2020 STbp->buffer_bytes);
2021 if (STps->drv_block >= 0)
2022 STps->drv_block += 1;
2023 if (st_int_ioctl(STp, MTBSR, 1))
2024 return (-EIO);
2025 }
2026 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
2027 if (STps->eof != ST_FM_HIT)
2028 STps->eof = ST_FM_HIT;
2029 else
2030 STps->eof = ST_EOD_2;
2031 if (STp->block_size == 0)
2032 STbp->buffer_bytes = 0;
2033 else
2034 STbp->buffer_bytes =
2035 bytes - transfer * STp->block_size;
2036 DEBC_printk(STp, "EOF detected (%d "
2037 "bytes read).\n",
2038 STbp->buffer_bytes);
2039 } else if (cmdstatp->flags & SENSE_EOM) {
2040 if (STps->eof == ST_FM)
2041 STps->eof = ST_EOD_1;
2042 else
2043 STps->eof = ST_EOM_OK;
2044 if (STp->block_size == 0)
2045 STbp->buffer_bytes = bytes - transfer;
2046 else
2047 STbp->buffer_bytes =
2048 bytes - transfer * STp->block_size;
2049
2050 DEBC_printk(STp, "EOM detected (%d "
2051 "bytes read).\n",
2052 STbp->buffer_bytes);
2053 }
2054 }
2055 /* end of EOF, EOM, ILI test */
2056 else { /* nonzero sense key */
2057 DEBC_printk(STp, "Tape error while reading.\n");
2058 STps->drv_block = (-1);
2059 if (STps->eof == ST_FM &&
2060 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
2061 DEBC_printk(STp, "Zero returned for "
2062 "first BLANK CHECK "
2063 "after EOF.\n");
2064 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
2065 } else /* Some other extended sense code */
2066 retval = (-EIO);
2067 }
2068
2069 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
2070 STbp->buffer_bytes = 0;
2071 }
2072 /* End of extended sense test */
2073 else { /* Non-extended sense */
2074 retval = STbp->syscall_result;
2075 }
2076
2077 }
2078 /* End of error handling */
2079 else { /* Read successful */
2080 STbp->buffer_bytes = bytes;
2081 if (STp->sili) /* In fixed block mode residual is always zero here */
2082 STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
2083 }
2084
2085 if (STps->drv_block >= 0) {
2086 if (STp->block_size == 0)
2087 STps->drv_block++;
2088 else
2089 STps->drv_block += STbp->buffer_bytes / STp->block_size;
2090 }
2091 return retval;
2092}
2093
2094
2095/* Read command */
2096static ssize_t
2097st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
2098{
2099 ssize_t total;
2100 ssize_t retval = 0;
2101 ssize_t i, transfer;
2102 int special, do_dio = 0;
2103 struct st_request *SRpnt = NULL;
2104 struct scsi_tape *STp = filp->private_data;
2105 struct st_modedef *STm;
2106 struct st_partstat *STps;
2107 struct st_buffer *STbp = STp->buffer;
2108
2109 if (mutex_lock_interruptible(&STp->lock))
2110 return -ERESTARTSYS;
2111
2112 retval = rw_checks(STp, filp, count);
2113 if (retval || count == 0)
2114 goto out;
2115
2116 STm = &(STp->modes[STp->current_mode]);
2117 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
2118 if (!STm->do_read_ahead) {
2119 retval = (-EINVAL); /* Read must be integral number of blocks */
2120 goto out;
2121 }
2122 STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
2123 }
2124
2125 STps = &(STp->ps[STp->partition]);
2126 if (STps->rw == ST_WRITING) {
2127 retval = flush_buffer(STp, 0);
2128 if (retval)
2129 goto out;
2130 STps->rw = ST_READING;
2131 }
2132 DEB(
2133 if (debugging && STps->eof != ST_NOEOF)
2134 st_printk(ST_DEB_MSG, STp,
2135 "EOF/EOM flag up (%d). Bytes %d\n",
2136 STps->eof, STbp->buffer_bytes);
2137 ) /* end DEB */
2138
2139 retval = setup_buffering(STp, buf, count, 1);
2140 if (retval)
2141 goto out;
2142 do_dio = STbp->do_dio;
2143
2144 if (STbp->buffer_bytes == 0 &&
2145 STps->eof >= ST_EOD_1) {
2146 if (STps->eof < ST_EOD) {
2147 STps->eof += 1;
2148 retval = 0;
2149 goto out;
2150 }
2151 retval = (-EIO); /* EOM or Blank Check */
2152 goto out;
2153 }
2154
2155 if (do_dio) {
2156 /* Check the buffer writability before any tape movement. Don't alter
2157 buffer data. */
2158 if (copy_from_user(&i, buf, 1) != 0 ||
2159 copy_to_user(buf, &i, 1) != 0 ||
2160 copy_from_user(&i, buf + count - 1, 1) != 0 ||
2161 copy_to_user(buf + count - 1, &i, 1) != 0) {
2162 retval = (-EFAULT);
2163 goto out;
2164 }
2165 }
2166
2167 STps->rw = ST_READING;
2168
2169
2170 /* Loop until enough data in buffer or a special condition found */
2171 for (total = 0, special = 0; total < count && !special;) {
2172
2173 /* Get new data if the buffer is empty */
2174 if (STbp->buffer_bytes == 0) {
2175 special = read_tape(STp, count - total, &SRpnt);
2176 if (special < 0) { /* No need to continue read */
2177 retval = special;
2178 goto out;
2179 }
2180 }
2181
2182 /* Move the data from driver buffer to user buffer */
2183 if (STbp->buffer_bytes > 0) {
2184 DEB(
2185 if (debugging && STps->eof != ST_NOEOF)
2186 st_printk(ST_DEB_MSG, STp,
2187 "EOF up (%d). Left %d, needed %d.\n",
2188 STps->eof, STbp->buffer_bytes,
2189 (int)(count - total));
2190 ) /* end DEB */
2191 transfer = STbp->buffer_bytes < count - total ?
2192 STbp->buffer_bytes : count - total;
2193 if (!do_dio) {
2194 i = from_buffer(STbp, buf, transfer);
2195 if (i) {
2196 retval = i;
2197 goto out;
2198 }
2199 }
2200 buf += transfer;
2201 total += transfer;
2202 }
2203
2204 if (STp->block_size == 0)
2205 break; /* Read only one variable length block */
2206
2207 } /* for (total = 0, special = 0;
2208 total < count && !special; ) */
2209
2210 /* Change the eof state if no data from tape or buffer */
2211 if (total == 0) {
2212 if (STps->eof == ST_FM_HIT) {
2213 STps->eof = ST_FM;
2214 STps->drv_block = 0;
2215 if (STps->drv_file >= 0)
2216 STps->drv_file++;
2217 } else if (STps->eof == ST_EOD_1) {
2218 STps->eof = ST_EOD_2;
2219 STps->drv_block = 0;
2220 if (STps->drv_file >= 0)
2221 STps->drv_file++;
2222 } else if (STps->eof == ST_EOD_2)
2223 STps->eof = ST_EOD;
2224 } else if (STps->eof == ST_FM)
2225 STps->eof = ST_NOEOF;
2226 retval = total;
2227
2228 out:
2229 if (SRpnt != NULL) {
2230 st_release_request(SRpnt);
2231 SRpnt = NULL;
2232 }
2233 if (do_dio) {
2234 release_buffering(STp, 1);
2235 STbp->buffer_bytes = 0;
2236 }
2237 mutex_unlock(&STp->lock);
2238
2239 return retval;
2240}
2241
2242
2243
2244DEB(
2245/* Set the driver options */
2246static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm)
2247{
2248 if (debugging) {
2249 st_printk(KERN_INFO, STp,
2250 "Mode %d options: buffer writes: %d, "
2251 "async writes: %d, read ahead: %d\n",
2252 STp->current_mode, STm->do_buffer_writes,
2253 STm->do_async_writes, STm->do_read_ahead);
2254 st_printk(KERN_INFO, STp,
2255 " can bsr: %d, two FMs: %d, "
2256 "fast mteom: %d, auto lock: %d,\n",
2257 STp->can_bsr, STp->two_fm, STp->fast_mteom,
2258 STp->do_auto_lock);
2259 st_printk(KERN_INFO, STp,
2260 " defs for wr: %d, no block limits: %d, "
2261 "partitions: %d, s2 log: %d\n",
2262 STm->defaults_for_writes, STp->omit_blklims,
2263 STp->can_partitions, STp->scsi2_logical);
2264 st_printk(KERN_INFO, STp,
2265 " sysv: %d nowait: %d sili: %d "
2266 "nowait_filemark: %d\n",
2267 STm->sysv, STp->immediate, STp->sili,
2268 STp->immediate_filemark);
2269 st_printk(KERN_INFO, STp, " debugging: %d\n", debugging);
2270 }
2271}
2272 )
2273
2274
2275static int st_set_options(struct scsi_tape *STp, long options)
2276{
2277 int value;
2278 long code;
2279 struct st_modedef *STm;
2280 struct cdev *cd0, *cd1;
2281 struct device *d0, *d1;
2282
2283 STm = &(STp->modes[STp->current_mode]);
2284 if (!STm->defined) {
2285 cd0 = STm->cdevs[0];
2286 cd1 = STm->cdevs[1];
2287 d0 = STm->devs[0];
2288 d1 = STm->devs[1];
2289 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2290 STm->cdevs[0] = cd0;
2291 STm->cdevs[1] = cd1;
2292 STm->devs[0] = d0;
2293 STm->devs[1] = d1;
2294 modes_defined = 1;
2295 DEBC_printk(STp, "Initialized mode %d definition from mode 0\n",
2296 STp->current_mode);
2297 }
2298
2299 code = options & MT_ST_OPTIONS;
2300 if (code == MT_ST_BOOLEANS) {
2301 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2302 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2303 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2304 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2305 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2306 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2307 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2308 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2309 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2310 if ((STp->device)->scsi_level >= SCSI_2)
2311 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2312 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2313 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2314 STp->immediate_filemark = (options & MT_ST_NOWAIT_EOF) != 0;
2315 STm->sysv = (options & MT_ST_SYSV) != 0;
2316 STp->sili = (options & MT_ST_SILI) != 0;
2317 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2318 st_log_options(STp, STm); )
2319 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2320 value = (code == MT_ST_SETBOOLEANS);
2321 if ((options & MT_ST_BUFFER_WRITES) != 0)
2322 STm->do_buffer_writes = value;
2323 if ((options & MT_ST_ASYNC_WRITES) != 0)
2324 STm->do_async_writes = value;
2325 if ((options & MT_ST_DEF_WRITES) != 0)
2326 STm->defaults_for_writes = value;
2327 if ((options & MT_ST_READ_AHEAD) != 0)
2328 STm->do_read_ahead = value;
2329 if ((options & MT_ST_TWO_FM) != 0)
2330 STp->two_fm = value;
2331 if ((options & MT_ST_FAST_MTEOM) != 0)
2332 STp->fast_mteom = value;
2333 if ((options & MT_ST_AUTO_LOCK) != 0)
2334 STp->do_auto_lock = value;
2335 if ((options & MT_ST_CAN_BSR) != 0)
2336 STp->can_bsr = value;
2337 if ((options & MT_ST_NO_BLKLIMS) != 0)
2338 STp->omit_blklims = value;
2339 if ((STp->device)->scsi_level >= SCSI_2 &&
2340 (options & MT_ST_CAN_PARTITIONS) != 0)
2341 STp->can_partitions = value;
2342 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2343 STp->scsi2_logical = value;
2344 if ((options & MT_ST_NOWAIT) != 0)
2345 STp->immediate = value;
2346 if ((options & MT_ST_NOWAIT_EOF) != 0)
2347 STp->immediate_filemark = value;
2348 if ((options & MT_ST_SYSV) != 0)
2349 STm->sysv = value;
2350 if ((options & MT_ST_SILI) != 0)
2351 STp->sili = value;
2352 DEB(
2353 if ((options & MT_ST_DEBUGGING) != 0)
2354 debugging = value;
2355 st_log_options(STp, STm); )
2356 } else if (code == MT_ST_WRITE_THRESHOLD) {
2357 /* Retained for compatibility */
2358 } else if (code == MT_ST_DEF_BLKSIZE) {
2359 value = (options & ~MT_ST_OPTIONS);
2360 if (value == ~MT_ST_OPTIONS) {
2361 STm->default_blksize = (-1);
2362 DEBC_printk(STp, "Default block size disabled.\n");
2363 } else {
2364 STm->default_blksize = value;
2365 DEBC_printk(STp,"Default block size set to "
2366 "%d bytes.\n", STm->default_blksize);
2367 if (STp->ready == ST_READY) {
2368 STp->blksize_changed = 0;
2369 set_mode_densblk(STp, STm);
2370 }
2371 }
2372 } else if (code == MT_ST_TIMEOUTS) {
2373 value = (options & ~MT_ST_OPTIONS);
2374 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2375 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2376 DEBC_printk(STp, "Long timeout set to %d seconds.\n",
2377 (value & ~MT_ST_SET_LONG_TIMEOUT));
2378 } else {
2379 blk_queue_rq_timeout(STp->device->request_queue,
2380 value * HZ);
2381 DEBC_printk(STp, "Normal timeout set to %d seconds.\n",
2382 value);
2383 }
2384 } else if (code == MT_ST_SET_CLN) {
2385 value = (options & ~MT_ST_OPTIONS) & 0xff;
2386 if (value != 0 &&
2387 (value < EXTENDED_SENSE_START ||
2388 value >= SCSI_SENSE_BUFFERSIZE))
2389 return (-EINVAL);
2390 STp->cln_mode = value;
2391 STp->cln_sense_mask = (options >> 8) & 0xff;
2392 STp->cln_sense_value = (options >> 16) & 0xff;
2393 st_printk(KERN_INFO, STp,
2394 "Cleaning request mode %d, mask %02x, value %02x\n",
2395 value, STp->cln_sense_mask, STp->cln_sense_value);
2396 } else if (code == MT_ST_DEF_OPTIONS) {
2397 code = (options & ~MT_ST_CLEAR_DEFAULT);
2398 value = (options & MT_ST_CLEAR_DEFAULT);
2399 if (code == MT_ST_DEF_DENSITY) {
2400 if (value == MT_ST_CLEAR_DEFAULT) {
2401 STm->default_density = (-1);
2402 DEBC_printk(STp,
2403 "Density default disabled.\n");
2404 } else {
2405 STm->default_density = value & 0xff;
2406 DEBC_printk(STp, "Density default set to %x\n",
2407 STm->default_density);
2408 if (STp->ready == ST_READY) {
2409 STp->density_changed = 0;
2410 set_mode_densblk(STp, STm);
2411 }
2412 }
2413 } else if (code == MT_ST_DEF_DRVBUFFER) {
2414 if (value == MT_ST_CLEAR_DEFAULT) {
2415 STp->default_drvbuffer = 0xff;
2416 DEBC_printk(STp,
2417 "Drive buffer default disabled.\n");
2418 } else {
2419 STp->default_drvbuffer = value & 7;
2420 DEBC_printk(STp,
2421 "Drive buffer default set to %x\n",
2422 STp->default_drvbuffer);
2423 if (STp->ready == ST_READY)
2424 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2425 }
2426 } else if (code == MT_ST_DEF_COMPRESSION) {
2427 if (value == MT_ST_CLEAR_DEFAULT) {
2428 STm->default_compression = ST_DONT_TOUCH;
2429 DEBC_printk(STp,
2430 "Compression default disabled.\n");
2431 } else {
2432 if ((value & 0xff00) != 0) {
2433 STp->c_algo = (value & 0xff00) >> 8;
2434 DEBC_printk(STp, "Compression "
2435 "algorithm set to 0x%x.\n",
2436 STp->c_algo);
2437 }
2438 if ((value & 0xff) != 0xff) {
2439 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2440 DEBC_printk(STp, "Compression default "
2441 "set to %x\n",
2442 (value & 1));
2443 if (STp->ready == ST_READY) {
2444 STp->compression_changed = 0;
2445 st_compression(STp, (STm->default_compression == ST_YES));
2446 }
2447 }
2448 }
2449 }
2450 } else
2451 return (-EIO);
2452
2453 return 0;
2454}
2455
2456#define MODE_HEADER_LENGTH 4
2457
2458/* Mode header and page byte offsets */
2459#define MH_OFF_DATA_LENGTH 0
2460#define MH_OFF_MEDIUM_TYPE 1
2461#define MH_OFF_DEV_SPECIFIC 2
2462#define MH_OFF_BDESCS_LENGTH 3
2463#define MP_OFF_PAGE_NBR 0
2464#define MP_OFF_PAGE_LENGTH 1
2465
2466/* Mode header and page bit masks */
2467#define MH_BIT_WP 0x80
2468#define MP_MSK_PAGE_NBR 0x3f
2469
2470/* Don't return block descriptors */
2471#define MODE_SENSE_OMIT_BDESCS 0x08
2472
2473#define MODE_SELECT_PAGE_FORMAT 0x10
2474
2475/* Read a mode page into the tape buffer. The block descriptors are included
2476 if incl_block_descs is true. The page control is ored to the page number
2477 parameter, if necessary. */
2478static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2479{
2480 unsigned char cmd[MAX_COMMAND_SIZE];
2481 struct st_request *SRpnt;
2482
2483 memset(cmd, 0, MAX_COMMAND_SIZE);
2484 cmd[0] = MODE_SENSE;
2485 if (omit_block_descs)
2486 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2487 cmd[2] = page;
2488 cmd[4] = 255;
2489
2490 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2491 STp->device->request_queue->rq_timeout, 0, 1);
2492 if (SRpnt == NULL)
2493 return (STp->buffer)->syscall_result;
2494
2495 st_release_request(SRpnt);
2496
2497 return STp->buffer->syscall_result;
2498}
2499
2500
2501/* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2502 in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
2503static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2504{
2505 int pgo;
2506 unsigned char cmd[MAX_COMMAND_SIZE];
2507 struct st_request *SRpnt;
2508 int timeout;
2509
2510 memset(cmd, 0, MAX_COMMAND_SIZE);
2511 cmd[0] = MODE_SELECT;
2512 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2513 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2514 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2515
2516 /* Clear reserved fields */
2517 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2518 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2519 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2520 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2521
2522 timeout = slow ?
2523 STp->long_timeout : STp->device->request_queue->rq_timeout;
2524 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
2525 timeout, 0, 1);
2526 if (SRpnt == NULL)
2527 return (STp->buffer)->syscall_result;
2528
2529 st_release_request(SRpnt);
2530
2531 return STp->buffer->syscall_result;
2532}
2533
2534
2535#define COMPRESSION_PAGE 0x0f
2536#define COMPRESSION_PAGE_LENGTH 16
2537
2538#define CP_OFF_DCE_DCC 2
2539#define CP_OFF_C_ALGO 7
2540
2541#define DCE_MASK 0x80
2542#define DCC_MASK 0x40
2543#define RED_MASK 0x60
2544
2545
2546/* Control the compression with mode page 15. Algorithm not changed if zero.
2547
2548 The block descriptors are read and written because Sony SDT-7000 does not
2549 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2550 Including block descriptors should not cause any harm to other drives. */
2551
2552static int st_compression(struct scsi_tape * STp, int state)
2553{
2554 int retval;
2555 int mpoffs; /* Offset to mode page start */
2556 unsigned char *b_data = (STp->buffer)->b_data;
2557
2558 if (STp->ready != ST_READY)
2559 return (-EIO);
2560
2561 /* Read the current page contents */
2562 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2563 if (retval) {
2564 DEBC_printk(STp, "Compression mode page not supported.\n");
2565 return (-EIO);
2566 }
2567
2568 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2569 DEBC_printk(STp, "Compression state is %d.\n",
2570 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0));
2571
2572 /* Check if compression can be changed */
2573 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2574 DEBC_printk(STp, "Compression not supported.\n");
2575 return (-EIO);
2576 }
2577
2578 /* Do the change */
2579 if (state) {
2580 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2581 if (STp->c_algo != 0)
2582 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2583 }
2584 else {
2585 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2586 if (STp->c_algo != 0)
2587 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2588 }
2589
2590 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2591 if (retval) {
2592 DEBC_printk(STp, "Compression change failed.\n");
2593 return (-EIO);
2594 }
2595 DEBC_printk(STp, "Compression state changed to %d.\n", state);
2596
2597 STp->compression_changed = 1;
2598 return 0;
2599}
2600
2601
2602/* Process the load and unload commands (does unload if the load code is zero) */
2603static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2604{
2605 int retval = (-EIO), timeout;
2606 unsigned char cmd[MAX_COMMAND_SIZE];
2607 struct st_partstat *STps;
2608 struct st_request *SRpnt;
2609
2610 if (STp->ready != ST_READY && !load_code) {
2611 if (STp->ready == ST_NO_TAPE)
2612 return (-ENOMEDIUM);
2613 else
2614 return (-EIO);
2615 }
2616
2617 memset(cmd, 0, MAX_COMMAND_SIZE);
2618 cmd[0] = START_STOP;
2619 if (load_code)
2620 cmd[4] |= 1;
2621 /*
2622 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2623 */
2624 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2625 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2626 DEBC_printk(STp, " Enhanced %sload slot %2d.\n",
2627 (cmd[4]) ? "" : "un",
2628 load_code - MT_ST_HPLOADER_OFFSET);
2629 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2630 }
2631 if (STp->immediate) {
2632 cmd[1] = 1; /* Don't wait for completion */
2633 timeout = STp->device->request_queue->rq_timeout;
2634 }
2635 else
2636 timeout = STp->long_timeout;
2637
2638 DEBC(
2639 if (!load_code)
2640 st_printk(ST_DEB_MSG, STp, "Unloading tape.\n");
2641 else
2642 st_printk(ST_DEB_MSG, STp, "Loading tape.\n");
2643 );
2644
2645 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2646 timeout, MAX_RETRIES, 1);
2647 if (!SRpnt)
2648 return (STp->buffer)->syscall_result;
2649
2650 retval = (STp->buffer)->syscall_result;
2651 st_release_request(SRpnt);
2652
2653 if (!retval) { /* SCSI command successful */
2654
2655 if (!load_code) {
2656 STp->rew_at_close = 0;
2657 STp->ready = ST_NO_TAPE;
2658 }
2659 else {
2660 STp->rew_at_close = STp->autorew_dev;
2661 retval = check_tape(STp, filp);
2662 if (retval > 0)
2663 retval = 0;
2664 }
2665 }
2666 else {
2667 STps = &(STp->ps[STp->partition]);
2668 STps->drv_file = STps->drv_block = (-1);
2669 }
2670
2671 return retval;
2672}
2673
2674#if DEBUG
2675#define ST_DEB_FORWARD 0
2676#define ST_DEB_BACKWARD 1
2677static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd)
2678{
2679 s32 sc;
2680
2681 if (!debugging)
2682 return;
2683
2684 sc = sign_extend32(get_unaligned_be24(&cmd[2]), 23);
2685 if (direction)
2686 sc = -sc;
2687 st_printk(ST_DEB_MSG, STp, "Spacing tape %s over %d %s.\n",
2688 direction ? "backward" : "forward", sc, units);
2689}
2690#else
2691#define ST_DEB_FORWARD 0
2692#define ST_DEB_BACKWARD 1
2693static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd) {}
2694#endif
2695
2696
2697/* Internal ioctl function */
2698static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2699{
2700 int timeout;
2701 long ltmp;
2702 int ioctl_result;
2703 int chg_eof = 1;
2704 unsigned char cmd[MAX_COMMAND_SIZE];
2705 struct st_request *SRpnt;
2706 struct st_partstat *STps;
2707 int fileno, blkno, at_sm, undone;
2708 int datalen = 0, direction = DMA_NONE;
2709
2710 WARN_ON(STp->buffer->do_dio != 0);
2711 if (STp->ready != ST_READY) {
2712 if (STp->ready == ST_NO_TAPE)
2713 return (-ENOMEDIUM);
2714 else
2715 return (-EIO);
2716 }
2717 timeout = STp->long_timeout;
2718 STps = &(STp->ps[STp->partition]);
2719 fileno = STps->drv_file;
2720 blkno = STps->drv_block;
2721 at_sm = STps->at_sm;
2722
2723 memset(cmd, 0, MAX_COMMAND_SIZE);
2724 switch (cmd_in) {
2725 case MTFSFM:
2726 chg_eof = 0; /* Changed from the FSF after this */
2727 fallthrough;
2728 case MTFSF:
2729 cmd[0] = SPACE;
2730 cmd[1] = 0x01; /* Space FileMarks */
2731 cmd[2] = (arg >> 16);
2732 cmd[3] = (arg >> 8);
2733 cmd[4] = arg;
2734 deb_space_print(STp, ST_DEB_FORWARD, "filemarks", cmd);
2735 if (fileno >= 0)
2736 fileno += arg;
2737 blkno = 0;
2738 at_sm &= (arg == 0);
2739 break;
2740 case MTBSFM:
2741 chg_eof = 0; /* Changed from the FSF after this */
2742 fallthrough;
2743 case MTBSF:
2744 cmd[0] = SPACE;
2745 cmd[1] = 0x01; /* Space FileMarks */
2746 ltmp = (-arg);
2747 cmd[2] = (ltmp >> 16);
2748 cmd[3] = (ltmp >> 8);
2749 cmd[4] = ltmp;
2750 deb_space_print(STp, ST_DEB_BACKWARD, "filemarks", cmd);
2751 if (fileno >= 0)
2752 fileno -= arg;
2753 blkno = (-1); /* We can't know the block number */
2754 at_sm &= (arg == 0);
2755 break;
2756 case MTFSR:
2757 cmd[0] = SPACE;
2758 cmd[1] = 0x00; /* Space Blocks */
2759 cmd[2] = (arg >> 16);
2760 cmd[3] = (arg >> 8);
2761 cmd[4] = arg;
2762 deb_space_print(STp, ST_DEB_FORWARD, "blocks", cmd);
2763 if (blkno >= 0)
2764 blkno += arg;
2765 at_sm &= (arg == 0);
2766 break;
2767 case MTBSR:
2768 cmd[0] = SPACE;
2769 cmd[1] = 0x00; /* Space Blocks */
2770 ltmp = (-arg);
2771 cmd[2] = (ltmp >> 16);
2772 cmd[3] = (ltmp >> 8);
2773 cmd[4] = ltmp;
2774 deb_space_print(STp, ST_DEB_BACKWARD, "blocks", cmd);
2775 if (blkno >= 0)
2776 blkno -= arg;
2777 at_sm &= (arg == 0);
2778 break;
2779 case MTFSS:
2780 cmd[0] = SPACE;
2781 cmd[1] = 0x04; /* Space Setmarks */
2782 cmd[2] = (arg >> 16);
2783 cmd[3] = (arg >> 8);
2784 cmd[4] = arg;
2785 deb_space_print(STp, ST_DEB_FORWARD, "setmarks", cmd);
2786 if (arg != 0) {
2787 blkno = fileno = (-1);
2788 at_sm = 1;
2789 }
2790 break;
2791 case MTBSS:
2792 cmd[0] = SPACE;
2793 cmd[1] = 0x04; /* Space Setmarks */
2794 ltmp = (-arg);
2795 cmd[2] = (ltmp >> 16);
2796 cmd[3] = (ltmp >> 8);
2797 cmd[4] = ltmp;
2798 deb_space_print(STp, ST_DEB_BACKWARD, "setmarks", cmd);
2799 if (arg != 0) {
2800 blkno = fileno = (-1);
2801 at_sm = 1;
2802 }
2803 break;
2804 case MTWEOF:
2805 case MTWEOFI:
2806 case MTWSM:
2807 if (STp->write_prot)
2808 return (-EACCES);
2809 cmd[0] = WRITE_FILEMARKS;
2810 if (cmd_in == MTWSM)
2811 cmd[1] = 2;
2812 if (cmd_in == MTWEOFI ||
2813 (cmd_in == MTWEOF && STp->immediate_filemark))
2814 cmd[1] |= 1;
2815 cmd[2] = (arg >> 16);
2816 cmd[3] = (arg >> 8);
2817 cmd[4] = arg;
2818 timeout = STp->device->request_queue->rq_timeout;
2819 DEBC(
2820 if (cmd_in != MTWSM)
2821 st_printk(ST_DEB_MSG, STp,
2822 "Writing %d filemarks.\n",
2823 cmd[2] * 65536 +
2824 cmd[3] * 256 +
2825 cmd[4]);
2826 else
2827 st_printk(ST_DEB_MSG, STp,
2828 "Writing %d setmarks.\n",
2829 cmd[2] * 65536 +
2830 cmd[3] * 256 +
2831 cmd[4]);
2832 )
2833 if (fileno >= 0)
2834 fileno += arg;
2835 blkno = 0;
2836 at_sm = (cmd_in == MTWSM);
2837 break;
2838 case MTREW:
2839 cmd[0] = REZERO_UNIT;
2840 if (STp->immediate) {
2841 cmd[1] = 1; /* Don't wait for completion */
2842 timeout = STp->device->request_queue->rq_timeout;
2843 }
2844 DEBC_printk(STp, "Rewinding tape.\n");
2845 fileno = blkno = at_sm = 0;
2846 break;
2847 case MTNOP:
2848 DEBC_printk(STp, "No op on tape.\n");
2849 return 0; /* Should do something ? */
2850 case MTRETEN:
2851 cmd[0] = START_STOP;
2852 if (STp->immediate) {
2853 cmd[1] = 1; /* Don't wait for completion */
2854 timeout = STp->device->request_queue->rq_timeout;
2855 }
2856 cmd[4] = 3;
2857 DEBC_printk(STp, "Retensioning tape.\n");
2858 fileno = blkno = at_sm = 0;
2859 break;
2860 case MTEOM:
2861 if (!STp->fast_mteom) {
2862 /* space to the end of tape */
2863 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2864 fileno = STps->drv_file;
2865 if (STps->eof >= ST_EOD_1)
2866 return 0;
2867 /* The next lines would hide the number of spaced FileMarks
2868 That's why I inserted the previous lines. I had no luck
2869 with detecting EOM with FSF, so we go now to EOM.
2870 Joerg Weule */
2871 } else
2872 fileno = (-1);
2873 cmd[0] = SPACE;
2874 cmd[1] = 3;
2875 DEBC_printk(STp, "Spacing to end of recorded medium.\n");
2876 blkno = -1;
2877 at_sm = 0;
2878 break;
2879 case MTERASE:
2880 if (STp->write_prot)
2881 return (-EACCES);
2882 cmd[0] = ERASE;
2883 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2884 if (STp->immediate) {
2885 cmd[1] |= 2; /* Don't wait for completion */
2886 timeout = STp->device->request_queue->rq_timeout;
2887 }
2888 else
2889 timeout = STp->long_timeout * 8;
2890
2891 DEBC_printk(STp, "Erasing tape.\n");
2892 fileno = blkno = at_sm = 0;
2893 break;
2894 case MTSETBLK: /* Set block length */
2895 case MTSETDENSITY: /* Set tape density */
2896 case MTSETDRVBUFFER: /* Set drive buffering */
2897 case SET_DENS_AND_BLK: /* Set density and block size */
2898 chg_eof = 0;
2899 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2900 return (-EIO); /* Not allowed if data in buffer */
2901 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2902 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2903 STp->max_block > 0 &&
2904 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2905 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2906 st_printk(KERN_WARNING, STp, "Illegal block size.\n");
2907 return (-EINVAL);
2908 }
2909 cmd[0] = MODE_SELECT;
2910 if ((STp->use_pf & USE_PF))
2911 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2912 cmd[4] = datalen = 12;
2913 direction = DMA_TO_DEVICE;
2914
2915 memset((STp->buffer)->b_data, 0, 12);
2916 if (cmd_in == MTSETDRVBUFFER)
2917 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2918 else
2919 (STp->buffer)->b_data[2] =
2920 STp->drv_buffer << 4;
2921 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2922 if (cmd_in == MTSETDENSITY) {
2923 (STp->buffer)->b_data[4] = arg;
2924 STp->density_changed = 1; /* At least we tried ;-) */
2925 } else if (cmd_in == SET_DENS_AND_BLK)
2926 (STp->buffer)->b_data[4] = arg >> 24;
2927 else
2928 (STp->buffer)->b_data[4] = STp->density;
2929 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2930 ltmp = arg & MT_ST_BLKSIZE_MASK;
2931 if (cmd_in == MTSETBLK)
2932 STp->blksize_changed = 1; /* At least we tried ;-) */
2933 } else
2934 ltmp = STp->block_size;
2935 (STp->buffer)->b_data[9] = (ltmp >> 16);
2936 (STp->buffer)->b_data[10] = (ltmp >> 8);
2937 (STp->buffer)->b_data[11] = ltmp;
2938 timeout = STp->device->request_queue->rq_timeout;
2939 DEBC(
2940 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2941 st_printk(ST_DEB_MSG, STp,
2942 "Setting block size to %d bytes.\n",
2943 (STp->buffer)->b_data[9] * 65536 +
2944 (STp->buffer)->b_data[10] * 256 +
2945 (STp->buffer)->b_data[11]);
2946 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2947 st_printk(ST_DEB_MSG, STp,
2948 "Setting density code to %x.\n",
2949 (STp->buffer)->b_data[4]);
2950 if (cmd_in == MTSETDRVBUFFER)
2951 st_printk(ST_DEB_MSG, STp,
2952 "Setting drive buffer code to %d.\n",
2953 ((STp->buffer)->b_data[2] >> 4) & 7);
2954 )
2955 break;
2956 default:
2957 return (-ENOSYS);
2958 }
2959
2960 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2961 timeout, MAX_RETRIES, 1);
2962 if (!SRpnt)
2963 return (STp->buffer)->syscall_result;
2964
2965 ioctl_result = (STp->buffer)->syscall_result;
2966
2967 if (!ioctl_result) { /* SCSI command successful */
2968 st_release_request(SRpnt);
2969 SRpnt = NULL;
2970 STps->drv_block = blkno;
2971 STps->drv_file = fileno;
2972 STps->at_sm = at_sm;
2973
2974 if (cmd_in == MTBSFM)
2975 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2976 else if (cmd_in == MTFSFM)
2977 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2978
2979 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2980 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2981 if (STp->block_size != 0) {
2982 (STp->buffer)->buffer_blocks =
2983 (STp->buffer)->buffer_size / STp->block_size;
2984 }
2985 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2986 if (cmd_in == SET_DENS_AND_BLK)
2987 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2988 } else if (cmd_in == MTSETDRVBUFFER)
2989 STp->drv_buffer = (arg & 7);
2990 else if (cmd_in == MTSETDENSITY)
2991 STp->density = arg;
2992
2993 if (cmd_in == MTEOM)
2994 STps->eof = ST_EOD;
2995 else if (cmd_in == MTFSF)
2996 STps->eof = ST_FM;
2997 else if (chg_eof)
2998 STps->eof = ST_NOEOF;
2999
3000 if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
3001 STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
3002 } else { /* SCSI command was not completely successful. Don't return
3003 from this block without releasing the SCSI command block! */
3004 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
3005
3006 if (cmdstatp->flags & SENSE_EOM) {
3007 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
3008 cmd_in != MTBSR && cmd_in != MTBSS)
3009 STps->eof = ST_EOM_OK;
3010 STps->drv_block = 0;
3011 }
3012
3013 if (cmdstatp->remainder_valid)
3014 undone = (int)cmdstatp->uremainder64;
3015 else
3016 undone = 0;
3017
3018 if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
3019 cmdstatp->have_sense &&
3020 (cmdstatp->flags & SENSE_EOM)) {
3021 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
3022 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
3023 ioctl_result = 0; /* EOF(s) written successfully at EOM */
3024 STps->eof = ST_NOEOF;
3025 } else { /* Writing EOF(s) failed */
3026 if (fileno >= 0)
3027 fileno -= undone;
3028 if (undone < arg)
3029 STps->eof = ST_NOEOF;
3030 }
3031 STps->drv_file = fileno;
3032 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
3033 if (fileno >= 0)
3034 STps->drv_file = fileno - undone;
3035 else
3036 STps->drv_file = fileno;
3037 STps->drv_block = -1;
3038 STps->eof = ST_NOEOF;
3039 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
3040 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3041 undone = (-undone);
3042 if (STps->drv_file >= 0)
3043 STps->drv_file = fileno + undone;
3044 STps->drv_block = 0;
3045 STps->eof = ST_NOEOF;
3046 } else if (cmd_in == MTFSR) {
3047 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3048 if (STps->drv_file >= 0)
3049 STps->drv_file++;
3050 STps->drv_block = 0;
3051 STps->eof = ST_FM;
3052 } else {
3053 if (blkno >= undone)
3054 STps->drv_block = blkno - undone;
3055 else
3056 STps->drv_block = (-1);
3057 STps->eof = ST_NOEOF;
3058 }
3059 } else if (cmd_in == MTBSR) {
3060 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3061 STps->drv_file--;
3062 STps->drv_block = (-1);
3063 } else {
3064 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3065 undone = (-undone);
3066 if (STps->drv_block >= 0)
3067 STps->drv_block = blkno + undone;
3068 }
3069 STps->eof = ST_NOEOF;
3070 } else if (cmd_in == MTEOM) {
3071 STps->drv_file = (-1);
3072 STps->drv_block = (-1);
3073 STps->eof = ST_EOD;
3074 } else if (cmd_in == MTSETBLK ||
3075 cmd_in == MTSETDENSITY ||
3076 cmd_in == MTSETDRVBUFFER ||
3077 cmd_in == SET_DENS_AND_BLK) {
3078 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
3079 !(STp->use_pf & PF_TESTED)) {
3080 /* Try the other possible state of Page Format if not
3081 already tried */
3082 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
3083 st_release_request(SRpnt);
3084 SRpnt = NULL;
3085 return st_int_ioctl(STp, cmd_in, arg);
3086 }
3087 } else if (chg_eof)
3088 STps->eof = ST_NOEOF;
3089
3090 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
3091 STps->eof = ST_EOD;
3092
3093 st_release_request(SRpnt);
3094 SRpnt = NULL;
3095 }
3096
3097 return ioctl_result;
3098}
3099
3100
3101/* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
3102 structure. */
3103
3104static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
3105 int logical)
3106{
3107 int result;
3108 unsigned char scmd[MAX_COMMAND_SIZE];
3109 struct st_request *SRpnt;
3110
3111 if (STp->ready != ST_READY)
3112 return (-EIO);
3113
3114 memset(scmd, 0, MAX_COMMAND_SIZE);
3115 if ((STp->device)->scsi_level < SCSI_2) {
3116 scmd[0] = QFA_REQUEST_BLOCK;
3117 scmd[4] = 3;
3118 } else {
3119 scmd[0] = READ_POSITION;
3120 if (!logical && !STp->scsi2_logical)
3121 scmd[1] = 1;
3122 }
3123 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3124 STp->device->request_queue->rq_timeout,
3125 MAX_READY_RETRIES, 1);
3126 if (!SRpnt)
3127 return (STp->buffer)->syscall_result;
3128
3129 if ((STp->buffer)->syscall_result != 0 ||
3130 (STp->device->scsi_level >= SCSI_2 &&
3131 ((STp->buffer)->b_data[0] & 4) != 0)) {
3132 *block = *partition = 0;
3133 DEBC_printk(STp, " Can't read tape position.\n");
3134 result = (-EIO);
3135 } else {
3136 result = 0;
3137 if ((STp->device)->scsi_level < SCSI_2) {
3138 *block = ((STp->buffer)->b_data[0] << 16)
3139 + ((STp->buffer)->b_data[1] << 8)
3140 + (STp->buffer)->b_data[2];
3141 *partition = 0;
3142 } else {
3143 *block = ((STp->buffer)->b_data[4] << 24)
3144 + ((STp->buffer)->b_data[5] << 16)
3145 + ((STp->buffer)->b_data[6] << 8)
3146 + (STp->buffer)->b_data[7];
3147 *partition = (STp->buffer)->b_data[1];
3148 if (((STp->buffer)->b_data[0] & 0x80) &&
3149 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3150 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3151 }
3152 DEBC_printk(STp, "Got tape pos. blk %d part %d.\n",
3153 *block, *partition);
3154 }
3155 st_release_request(SRpnt);
3156 SRpnt = NULL;
3157
3158 return result;
3159}
3160
3161
3162/* Set the tape block and partition. Negative partition means that only the
3163 block should be set in vendor specific way. */
3164static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3165 int logical)
3166{
3167 struct st_partstat *STps;
3168 int result, p;
3169 unsigned int blk;
3170 int timeout;
3171 unsigned char scmd[MAX_COMMAND_SIZE];
3172 struct st_request *SRpnt;
3173
3174 if (STp->ready != ST_READY)
3175 return (-EIO);
3176 timeout = STp->long_timeout;
3177 STps = &(STp->ps[STp->partition]);
3178
3179 DEBC_printk(STp, "Setting block to %d and partition to %d.\n",
3180 block, partition);
3181 DEB(if (partition < 0)
3182 return (-EIO); )
3183
3184 /* Update the location at the partition we are leaving */
3185 if ((!STp->can_partitions && partition != 0) ||
3186 partition >= ST_NBR_PARTITIONS)
3187 return (-EINVAL);
3188 if (partition != STp->partition) {
3189 if (get_location(STp, &blk, &p, 1))
3190 STps->last_block_valid = 0;
3191 else {
3192 STps->last_block_valid = 1;
3193 STps->last_block_visited = blk;
3194 DEBC_printk(STp, "Visited block %d for "
3195 "partition %d saved.\n",
3196 blk, STp->partition);
3197 }
3198 }
3199
3200 memset(scmd, 0, MAX_COMMAND_SIZE);
3201 if ((STp->device)->scsi_level < SCSI_2) {
3202 scmd[0] = QFA_SEEK_BLOCK;
3203 scmd[2] = (block >> 16);
3204 scmd[3] = (block >> 8);
3205 scmd[4] = block;
3206 scmd[5] = 0;
3207 } else {
3208 scmd[0] = SEEK_10;
3209 scmd[3] = (block >> 24);
3210 scmd[4] = (block >> 16);
3211 scmd[5] = (block >> 8);
3212 scmd[6] = block;
3213 if (!logical && !STp->scsi2_logical)
3214 scmd[1] = 4;
3215 if (STp->partition != partition) {
3216 scmd[1] |= 2;
3217 scmd[8] = partition;
3218 DEBC_printk(STp, "Trying to change partition "
3219 "from %d to %d\n", STp->partition,
3220 partition);
3221 }
3222 }
3223 if (STp->immediate) {
3224 scmd[1] |= 1; /* Don't wait for completion */
3225 timeout = STp->device->request_queue->rq_timeout;
3226 }
3227
3228 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3229 timeout, MAX_READY_RETRIES, 1);
3230 if (!SRpnt)
3231 return (STp->buffer)->syscall_result;
3232
3233 STps->drv_block = STps->drv_file = (-1);
3234 STps->eof = ST_NOEOF;
3235 if ((STp->buffer)->syscall_result != 0) {
3236 result = (-EIO);
3237 if (STp->can_partitions &&
3238 (STp->device)->scsi_level >= SCSI_2 &&
3239 (p = find_partition(STp)) >= 0)
3240 STp->partition = p;
3241 } else {
3242 if (STp->can_partitions) {
3243 STp->partition = partition;
3244 STps = &(STp->ps[partition]);
3245 if (!STps->last_block_valid ||
3246 STps->last_block_visited != block) {
3247 STps->at_sm = 0;
3248 STps->rw = ST_IDLE;
3249 }
3250 } else
3251 STps->at_sm = 0;
3252 if (block == 0)
3253 STps->drv_block = STps->drv_file = 0;
3254 result = 0;
3255 }
3256
3257 st_release_request(SRpnt);
3258 SRpnt = NULL;
3259
3260 return result;
3261}
3262
3263
3264/* Find the current partition number for the drive status. Called from open and
3265 returns either partition number of negative error code. */
3266static int find_partition(struct scsi_tape *STp)
3267{
3268 int i, partition;
3269 unsigned int block;
3270
3271 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3272 return i;
3273 if (partition >= ST_NBR_PARTITIONS)
3274 return (-EIO);
3275 return partition;
3276}
3277
3278
3279/* Change the partition if necessary */
3280static int switch_partition(struct scsi_tape *STp)
3281{
3282 struct st_partstat *STps;
3283
3284 if (STp->partition == STp->new_partition)
3285 return 0;
3286 STps = &(STp->ps[STp->new_partition]);
3287 if (!STps->last_block_valid)
3288 STps->last_block_visited = 0;
3289 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3290}
3291
3292/* Functions for reading and writing the medium partition mode page. */
3293
3294#define PART_PAGE 0x11
3295#define PART_PAGE_FIXED_LENGTH 8
3296
3297#define PP_OFF_MAX_ADD_PARTS 2
3298#define PP_OFF_NBR_ADD_PARTS 3
3299#define PP_OFF_FLAGS 4
3300#define PP_OFF_PART_UNITS 6
3301#define PP_OFF_RESERVED 7
3302
3303#define PP_BIT_IDP 0x20
3304#define PP_BIT_FDP 0x80
3305#define PP_MSK_PSUM_MB 0x10
3306#define PP_MSK_PSUM_UNITS 0x18
3307#define PP_MSK_POFM 0x04
3308
3309/* Get the number of partitions on the tape. As a side effect reads the
3310 mode page into the tape buffer. */
3311static int nbr_partitions(struct scsi_tape *STp)
3312{
3313 int result;
3314
3315 if (STp->ready != ST_READY)
3316 return (-EIO);
3317
3318 result = read_mode_page(STp, PART_PAGE, 1);
3319
3320 if (result) {
3321 DEBC_printk(STp, "Can't read medium partition page.\n");
3322 result = (-EIO);
3323 } else {
3324 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3325 PP_OFF_NBR_ADD_PARTS] + 1;
3326 DEBC_printk(STp, "Number of partitions %d.\n", result);
3327 }
3328
3329 return result;
3330}
3331
3332
3333static int format_medium(struct scsi_tape *STp, int format)
3334{
3335 int result = 0;
3336 int timeout = STp->long_timeout;
3337 unsigned char scmd[MAX_COMMAND_SIZE];
3338 struct st_request *SRpnt;
3339
3340 memset(scmd, 0, MAX_COMMAND_SIZE);
3341 scmd[0] = FORMAT_UNIT;
3342 scmd[2] = format;
3343 if (STp->immediate) {
3344 scmd[1] |= 1; /* Don't wait for completion */
3345 timeout = STp->device->request_queue->rq_timeout;
3346 }
3347 DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
3348 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3349 timeout, MAX_RETRIES, 1);
3350 if (!SRpnt)
3351 result = STp->buffer->syscall_result;
3352 return result;
3353}
3354
3355
3356/* Partition the tape into two partitions if size > 0 or one partition if
3357 size == 0.
3358
3359 The block descriptors are read and written because Sony SDT-7000 does not
3360 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3361
3362 My HP C1533A drive returns only one partition size field. This is used to
3363 set the size of partition 1. There is no size field for the default partition.
3364 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3365 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3366 The following algorithm is used to accommodate both drives: if the number of
3367 partition size fields is greater than the maximum number of additional partitions
3368 in the mode page, the second field is used. Otherwise the first field is used.
3369
3370 For Seagate DDS drives the page length must be 8 when no partitions is defined
3371 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3372 is acceptable also to some other old drives and enforced if the first partition
3373 size field is used for the first additional partition size.
3374
3375 For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
3376 */
3377static int partition_tape(struct scsi_tape *STp, int size)
3378{
3379 int result;
3380 int target_partition;
3381 bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
3382 int pgo, psd_cnt, psdo;
3383 int psum = PP_MSK_PSUM_MB, units = 0;
3384 unsigned char *bp;
3385
3386 result = read_mode_page(STp, PART_PAGE, 0);
3387 if (result) {
3388 DEBC_printk(STp, "Can't read partition mode page.\n");
3389 return result;
3390 }
3391 target_partition = 1;
3392 if (size < 0) {
3393 target_partition = 0;
3394 size = -size;
3395 }
3396
3397 /* The mode page is in the buffer. Let's modify it and write it. */
3398 bp = (STp->buffer)->b_data;
3399 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3400 DEBC_printk(STp, "Partition page length is %d bytes.\n",
3401 bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
3402
3403 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3404
3405 if (scsi3) {
3406 needs_format = (bp[pgo + PP_OFF_FLAGS] & PP_MSK_POFM) != 0;
3407 if (needs_format && size == 0) {
3408 /* No need to write the mode page when clearing
3409 * partitioning
3410 */
3411 DEBC_printk(STp, "Formatting tape with one partition.\n");
3412 result = format_medium(STp, 0);
3413 goto out;
3414 }
3415 if (needs_format) /* Leave the old value for HP DATs claiming SCSI_3 */
3416 psd_cnt = 2;
3417 if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) == PP_MSK_PSUM_UNITS) {
3418 /* Use units scaling for large partitions if the device
3419 * suggests it and no precision lost. Required for IBM
3420 * TS1140/50 drives that don't support MB units.
3421 */
3422 if (size >= 1000 && (size % 1000) == 0) {
3423 size /= 1000;
3424 psum = PP_MSK_PSUM_UNITS;
3425 units = 9; /* GB */
3426 }
3427 }
3428 /* Try it anyway if too large to specify in MB */
3429 if (psum == PP_MSK_PSUM_MB && size >= 65534) {
3430 size /= 1000;
3431 psum = PP_MSK_PSUM_UNITS;
3432 units = 9; /* GB */
3433 }
3434 }
3435
3436 if (size >= 65535 || /* Does not fit into two bytes */
3437 (target_partition == 0 && psd_cnt < 2)) {
3438 result = -EINVAL;
3439 goto out;
3440 }
3441
3442 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3443 /* The second condition is for HP DDS which use only one partition size
3444 * descriptor
3445 */
3446 if (target_partition > 0 &&
3447 (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS] ||
3448 bp[pgo + PP_OFF_MAX_ADD_PARTS] != 1)) {
3449 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest to partition 0 */
3450 psdo += 2;
3451 }
3452 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3453
3454 DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
3455 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3456 bp[pgo + PP_OFF_NBR_ADD_PARTS]);
3457
3458 if (size == 0) {
3459 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3460 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3461 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3462 DEBC_printk(STp, "Formatting tape with one partition.\n");
3463 } else {
3464 bp[psdo] = (size >> 8) & 0xff;
3465 bp[psdo + 1] = size & 0xff;
3466 if (target_partition == 0)
3467 bp[psdo + 2] = bp[psdo + 3] = 0xff;
3468 bp[pgo + 3] = 1;
3469 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3470 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3471 DEBC_printk(STp,
3472 "Formatting tape with two partitions (%i = %d MB).\n",
3473 target_partition, units > 0 ? size * 1000 : size);
3474 }
3475 bp[pgo + PP_OFF_PART_UNITS] = 0;
3476 bp[pgo + PP_OFF_RESERVED] = 0;
3477 if (size != 1 || units != 0) {
3478 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
3479 (bp[pgo + PP_OFF_FLAGS] & 0x07);
3480 bp[pgo + PP_OFF_PART_UNITS] = units;
3481 } else
3482 bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
3483 (bp[pgo + PP_OFF_FLAGS] & 0x1f);
3484 bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
3485
3486 result = write_mode_page(STp, PART_PAGE, 1);
3487
3488 if (!result && needs_format)
3489 result = format_medium(STp, 1);
3490
3491 if (result) {
3492 st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
3493 result = (-EIO);
3494 }
3495
3496out:
3497 return result;
3498}
3499
3500
3501
3502/* The ioctl command */
3503static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3504{
3505 void __user *p = (void __user *)arg;
3506 int i, cmd_nr, cmd_type, bt;
3507 int retval = 0;
3508 unsigned int blk;
3509 struct scsi_tape *STp = file->private_data;
3510 struct st_modedef *STm;
3511 struct st_partstat *STps;
3512
3513 if (mutex_lock_interruptible(&STp->lock))
3514 return -ERESTARTSYS;
3515
3516 DEB(
3517 if (debugging && !STp->in_use) {
3518 st_printk(ST_DEB_MSG, STp, "Incorrect device.\n");
3519 retval = (-EIO);
3520 goto out;
3521 } ) /* end DEB */
3522
3523 STm = &(STp->modes[STp->current_mode]);
3524 STps = &(STp->ps[STp->partition]);
3525
3526 /*
3527 * If we are in the middle of error recovery, don't let anyone
3528 * else try and use this device. Also, if error recovery fails, it
3529 * may try and take the device offline, in which case all further
3530 * access to the device is prohibited.
3531 */
3532 retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
3533 file->f_flags & O_NDELAY);
3534 if (retval)
3535 goto out;
3536
3537 cmd_type = _IOC_TYPE(cmd_in);
3538 cmd_nr = _IOC_NR(cmd_in);
3539
3540 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3541 struct mtop mtc;
3542
3543 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3544 retval = (-EINVAL);
3545 goto out;
3546 }
3547
3548 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3549 if (i) {
3550 retval = (-EFAULT);
3551 goto out;
3552 }
3553
3554 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3555 st_printk(KERN_WARNING, STp,
3556 "MTSETDRVBUFFER only allowed for root.\n");
3557 retval = (-EPERM);
3558 goto out;
3559 }
3560 if (!STm->defined &&
3561 (mtc.mt_op != MTSETDRVBUFFER &&
3562 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3563 retval = (-ENXIO);
3564 goto out;
3565 }
3566
3567 if (!STp->pos_unknown) {
3568
3569 if (STps->eof == ST_FM_HIT) {
3570 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3571 mtc.mt_op == MTEOM) {
3572 mtc.mt_count -= 1;
3573 if (STps->drv_file >= 0)
3574 STps->drv_file += 1;
3575 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3576 mtc.mt_count += 1;
3577 if (STps->drv_file >= 0)
3578 STps->drv_file += 1;
3579 }
3580 }
3581
3582 if (mtc.mt_op == MTSEEK) {
3583 /* Old position must be restored if partition will be
3584 changed */
3585 i = !STp->can_partitions ||
3586 (STp->new_partition != STp->partition);
3587 } else {
3588 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3589 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3590 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3591 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3592 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3593 mtc.mt_op == MTCOMPRESSION;
3594 }
3595 i = flush_buffer(STp, i);
3596 if (i < 0) {
3597 retval = i;
3598 goto out;
3599 }
3600 if (STps->rw == ST_WRITING &&
3601 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3602 mtc.mt_op == MTSEEK ||
3603 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3604 i = st_int_ioctl(STp, MTWEOF, 1);
3605 if (i < 0) {
3606 retval = i;
3607 goto out;
3608 }
3609 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3610 mtc.mt_count++;
3611 STps->rw = ST_IDLE;
3612 }
3613
3614 } else {
3615 /*
3616 * If there was a bus reset, block further access
3617 * to this device. If the user wants to rewind the tape,
3618 * then reset the flag and allow access again.
3619 */
3620 if (mtc.mt_op != MTREW &&
3621 mtc.mt_op != MTOFFL &&
3622 mtc.mt_op != MTRETEN &&
3623 mtc.mt_op != MTERASE &&
3624 mtc.mt_op != MTSEEK &&
3625 mtc.mt_op != MTEOM) {
3626 retval = (-EIO);
3627 goto out;
3628 }
3629 reset_state(STp);
3630 /* remove this when the midlevel properly clears was_reset */
3631 STp->device->was_reset = 0;
3632 }
3633
3634 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3635 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3636 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3637 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3638
3639 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3640 do_door_lock(STp, 0); /* Ignore result! */
3641
3642 if (mtc.mt_op == MTSETDRVBUFFER &&
3643 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3644 retval = st_set_options(STp, mtc.mt_count);
3645 goto out;
3646 }
3647
3648 if (mtc.mt_op == MTSETPART) {
3649 if (!STp->can_partitions ||
3650 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3651 retval = (-EINVAL);
3652 goto out;
3653 }
3654 if (mtc.mt_count >= STp->nbr_partitions &&
3655 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3656 retval = (-EIO);
3657 goto out;
3658 }
3659 if (mtc.mt_count >= STp->nbr_partitions) {
3660 retval = (-EINVAL);
3661 goto out;
3662 }
3663 STp->new_partition = mtc.mt_count;
3664 retval = 0;
3665 goto out;
3666 }
3667
3668 if (mtc.mt_op == MTMKPART) {
3669 if (!STp->can_partitions) {
3670 retval = (-EINVAL);
3671 goto out;
3672 }
3673 i = do_load_unload(STp, file, 1);
3674 if (i < 0) {
3675 retval = i;
3676 goto out;
3677 }
3678 i = partition_tape(STp, mtc.mt_count);
3679 if (i < 0) {
3680 retval = i;
3681 goto out;
3682 }
3683 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3684 STp->ps[i].rw = ST_IDLE;
3685 STp->ps[i].at_sm = 0;
3686 STp->ps[i].last_block_valid = 0;
3687 }
3688 STp->partition = STp->new_partition = 0;
3689 STp->nbr_partitions = mtc.mt_count != 0 ? 2 : 1;
3690 STps->drv_block = STps->drv_file = 0;
3691 retval = 0;
3692 goto out;
3693 }
3694
3695 if (mtc.mt_op == MTSEEK) {
3696 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3697 if (!STp->can_partitions)
3698 STp->ps[0].rw = ST_IDLE;
3699 retval = i;
3700 goto out;
3701 }
3702
3703 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3704 retval = do_load_unload(STp, file, 0);
3705 goto out;
3706 }
3707
3708 if (mtc.mt_op == MTLOAD) {
3709 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3710 goto out;
3711 }
3712
3713 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3714 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3715 goto out;
3716 }
3717
3718 if (STp->can_partitions && STp->ready == ST_READY &&
3719 (i = switch_partition(STp)) < 0) {
3720 retval = i;
3721 goto out;
3722 }
3723
3724 if (mtc.mt_op == MTCOMPRESSION)
3725 retval = st_compression(STp, (mtc.mt_count & 1));
3726 else
3727 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3728 goto out;
3729 }
3730 if (!STm->defined) {
3731 retval = (-ENXIO);
3732 goto out;
3733 }
3734
3735 if ((i = flush_buffer(STp, 0)) < 0) {
3736 retval = i;
3737 goto out;
3738 }
3739 if (STp->can_partitions &&
3740 (i = switch_partition(STp)) < 0) {
3741 retval = i;
3742 goto out;
3743 }
3744
3745 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3746 struct mtget mt_status;
3747
3748 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3749 retval = (-EINVAL);
3750 goto out;
3751 }
3752
3753 mt_status.mt_type = STp->tape_type;
3754 mt_status.mt_dsreg =
3755 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3756 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3757 mt_status.mt_blkno = STps->drv_block;
3758 mt_status.mt_fileno = STps->drv_file;
3759 if (STp->block_size != 0) {
3760 if (STps->rw == ST_WRITING)
3761 mt_status.mt_blkno +=
3762 (STp->buffer)->buffer_bytes / STp->block_size;
3763 else if (STps->rw == ST_READING)
3764 mt_status.mt_blkno -=
3765 ((STp->buffer)->buffer_bytes +
3766 STp->block_size - 1) / STp->block_size;
3767 }
3768
3769 mt_status.mt_gstat = 0;
3770 if (STp->drv_write_prot)
3771 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3772 if (mt_status.mt_blkno == 0) {
3773 if (mt_status.mt_fileno == 0)
3774 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3775 else
3776 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3777 }
3778 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3779 mt_status.mt_resid = STp->partition;
3780 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3781 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3782 else if (STps->eof >= ST_EOM_OK)
3783 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3784 if (STp->density == 1)
3785 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3786 else if (STp->density == 2)
3787 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3788 else if (STp->density == 3)
3789 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3790 if (STp->ready == ST_READY)
3791 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3792 if (STp->ready == ST_NO_TAPE)
3793 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3794 if (STps->at_sm)
3795 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3796 if (STm->do_async_writes ||
3797 (STm->do_buffer_writes && STp->block_size != 0) ||
3798 STp->drv_buffer != 0)
3799 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3800 if (STp->cleaning_req)
3801 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3802
3803 retval = put_user_mtget(p, &mt_status);
3804 if (retval)
3805 goto out;
3806
3807 STp->recover_reg = 0; /* Clear after read */
3808 goto out;
3809 } /* End of MTIOCGET */
3810 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3811 struct mtpos mt_pos;
3812 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3813 retval = (-EINVAL);
3814 goto out;
3815 }
3816 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3817 retval = i;
3818 goto out;
3819 }
3820 mt_pos.mt_blkno = blk;
3821 retval = put_user_mtpos(p, &mt_pos);
3822 goto out;
3823 }
3824 mutex_unlock(&STp->lock);
3825
3826 switch (cmd_in) {
3827 case SG_IO:
3828 case SCSI_IOCTL_SEND_COMMAND:
3829 case CDROM_SEND_PACKET:
3830 if (!capable(CAP_SYS_RAWIO))
3831 return -EPERM;
3832 break;
3833 default:
3834 break;
3835 }
3836
3837 retval = scsi_ioctl(STp->device, file->f_mode & FMODE_WRITE, cmd_in, p);
3838 if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) {
3839 /* unload */
3840 STp->rew_at_close = 0;
3841 STp->ready = ST_NO_TAPE;
3842 }
3843 return retval;
3844
3845 out:
3846 mutex_unlock(&STp->lock);
3847 return retval;
3848}
3849
3850#ifdef CONFIG_COMPAT
3851static long st_compat_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3852{
3853 /* argument conversion is handled using put_user_mtpos/put_user_mtget */
3854 switch (cmd_in) {
3855 case MTIOCPOS32:
3856 cmd_in = MTIOCPOS;
3857 break;
3858 case MTIOCGET32:
3859 cmd_in = MTIOCGET;
3860 break;
3861 }
3862
3863 return st_ioctl(file, cmd_in, arg);
3864}
3865#endif
3866
3867
3868
3869/* Try to allocate a new tape buffer. Calling function must not hold
3870 dev_arr_lock. */
3871static struct st_buffer *new_tape_buffer(int max_sg)
3872{
3873 struct st_buffer *tb;
3874
3875 tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
3876 if (!tb) {
3877 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3878 return NULL;
3879 }
3880 tb->frp_segs = 0;
3881 tb->use_sg = max_sg;
3882 tb->buffer_size = 0;
3883
3884 tb->reserved_pages = kcalloc(max_sg, sizeof(struct page *),
3885 GFP_KERNEL);
3886 if (!tb->reserved_pages) {
3887 kfree(tb);
3888 return NULL;
3889 }
3890
3891 return tb;
3892}
3893
3894
3895/* Try to allocate enough space in the tape buffer */
3896#define ST_MAX_ORDER 6
3897
3898static int enlarge_buffer(struct st_buffer * STbuffer, int new_size)
3899{
3900 int segs, max_segs, b_size, order, got;
3901 gfp_t priority;
3902
3903 if (new_size <= STbuffer->buffer_size)
3904 return 1;
3905
3906 if (STbuffer->buffer_size <= PAGE_SIZE)
3907 normalize_buffer(STbuffer); /* Avoid extra segment */
3908
3909 max_segs = STbuffer->use_sg;
3910
3911 priority = GFP_KERNEL | __GFP_NOWARN;
3912
3913 if (STbuffer->cleared)
3914 priority |= __GFP_ZERO;
3915
3916 if (STbuffer->frp_segs) {
3917 order = STbuffer->reserved_page_order;
3918 b_size = PAGE_SIZE << order;
3919 } else {
3920 for (b_size = PAGE_SIZE, order = 0;
3921 order < ST_MAX_ORDER &&
3922 max_segs * (PAGE_SIZE << order) < new_size;
3923 order++, b_size *= 2)
3924 ; /* empty */
3925 STbuffer->reserved_page_order = order;
3926 }
3927 if (max_segs * (PAGE_SIZE << order) < new_size) {
3928 if (order == ST_MAX_ORDER)
3929 return 0;
3930 normalize_buffer(STbuffer);
3931 return enlarge_buffer(STbuffer, new_size);
3932 }
3933
3934 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3935 segs < max_segs && got < new_size;) {
3936 struct page *page;
3937
3938 page = alloc_pages(priority, order);
3939 if (!page) {
3940 DEB(STbuffer->buffer_size = got);
3941 normalize_buffer(STbuffer);
3942 return 0;
3943 }
3944
3945 STbuffer->frp_segs += 1;
3946 got += b_size;
3947 STbuffer->buffer_size = got;
3948 STbuffer->reserved_pages[segs] = page;
3949 segs++;
3950 }
3951 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3952
3953 return 1;
3954}
3955
3956
3957/* Make sure that no data from previous user is in the internal buffer */
3958static void clear_buffer(struct st_buffer * st_bp)
3959{
3960 int i;
3961
3962 for (i=0; i < st_bp->frp_segs; i++)
3963 memset(page_address(st_bp->reserved_pages[i]), 0,
3964 PAGE_SIZE << st_bp->reserved_page_order);
3965 st_bp->cleared = 1;
3966}
3967
3968
3969/* Release the extra buffer */
3970static void normalize_buffer(struct st_buffer * STbuffer)
3971{
3972 int i, order = STbuffer->reserved_page_order;
3973
3974 for (i = 0; i < STbuffer->frp_segs; i++) {
3975 __free_pages(STbuffer->reserved_pages[i], order);
3976 STbuffer->buffer_size -= (PAGE_SIZE << order);
3977 }
3978 STbuffer->frp_segs = 0;
3979 STbuffer->sg_segs = 0;
3980 STbuffer->reserved_page_order = 0;
3981 STbuffer->map_data.offset = 0;
3982}
3983
3984
3985/* Move data from the user buffer to the tape buffer. Returns zero (success) or
3986 negative error code. */
3987static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
3988{
3989 int i, cnt, res, offset;
3990 int length = PAGE_SIZE << st_bp->reserved_page_order;
3991
3992 for (i = 0, offset = st_bp->buffer_bytes;
3993 i < st_bp->frp_segs && offset >= length; i++)
3994 offset -= length;
3995 if (i == st_bp->frp_segs) { /* Should never happen */
3996 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
3997 return (-EIO);
3998 }
3999 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4000 struct page *page = st_bp->reserved_pages[i];
4001 cnt = length - offset < do_count ? length - offset : do_count;
4002 res = copy_from_user(page_address(page) + offset, ubp, cnt);
4003 if (res)
4004 return (-EFAULT);
4005 do_count -= cnt;
4006 st_bp->buffer_bytes += cnt;
4007 ubp += cnt;
4008 offset = 0;
4009 }
4010 if (do_count) /* Should never happen */
4011 return (-EIO);
4012
4013 return 0;
4014}
4015
4016
4017/* Move data from the tape buffer to the user buffer. Returns zero (success) or
4018 negative error code. */
4019static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
4020{
4021 int i, cnt, res, offset;
4022 int length = PAGE_SIZE << st_bp->reserved_page_order;
4023
4024 for (i = 0, offset = st_bp->read_pointer;
4025 i < st_bp->frp_segs && offset >= length; i++)
4026 offset -= length;
4027 if (i == st_bp->frp_segs) { /* Should never happen */
4028 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
4029 return (-EIO);
4030 }
4031 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4032 struct page *page = st_bp->reserved_pages[i];
4033 cnt = length - offset < do_count ? length - offset : do_count;
4034 res = copy_to_user(ubp, page_address(page) + offset, cnt);
4035 if (res)
4036 return (-EFAULT);
4037 do_count -= cnt;
4038 st_bp->buffer_bytes -= cnt;
4039 st_bp->read_pointer += cnt;
4040 ubp += cnt;
4041 offset = 0;
4042 }
4043 if (do_count) /* Should never happen */
4044 return (-EIO);
4045
4046 return 0;
4047}
4048
4049
4050/* Move data towards start of buffer */
4051static void move_buffer_data(struct st_buffer * st_bp, int offset)
4052{
4053 int src_seg, dst_seg, src_offset = 0, dst_offset;
4054 int count, total;
4055 int length = PAGE_SIZE << st_bp->reserved_page_order;
4056
4057 if (offset == 0)
4058 return;
4059
4060 total=st_bp->buffer_bytes - offset;
4061 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
4062 src_offset = offset;
4063 if (src_offset < length)
4064 break;
4065 offset -= length;
4066 }
4067
4068 st_bp->buffer_bytes = st_bp->read_pointer = total;
4069 for (dst_seg=dst_offset=0; total > 0; ) {
4070 struct page *dpage = st_bp->reserved_pages[dst_seg];
4071 struct page *spage = st_bp->reserved_pages[src_seg];
4072
4073 count = min(length - dst_offset, length - src_offset);
4074 memmove(page_address(dpage) + dst_offset,
4075 page_address(spage) + src_offset, count);
4076 src_offset += count;
4077 if (src_offset >= length) {
4078 src_seg++;
4079 src_offset = 0;
4080 }
4081 dst_offset += count;
4082 if (dst_offset >= length) {
4083 dst_seg++;
4084 dst_offset = 0;
4085 }
4086 total -= count;
4087 }
4088}
4089
4090/* Validate the options from command line or module parameters */
4091static void validate_options(void)
4092{
4093 if (buffer_kbs > 0)
4094 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
4095 if (max_sg_segs >= ST_FIRST_SG)
4096 st_max_sg_segs = max_sg_segs;
4097}
4098
4099#ifndef MODULE
4100/* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
4101 */
4102static int __init st_setup(char *str)
4103{
4104 int i, len, ints[5];
4105 char *stp;
4106
4107 stp = get_options(str, ARRAY_SIZE(ints), ints);
4108
4109 if (ints[0] > 0) {
4110 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
4111 if (parms[i].val)
4112 *parms[i].val = ints[i + 1];
4113 } else {
4114 while (stp != NULL) {
4115 for (i = 0; i < ARRAY_SIZE(parms); i++) {
4116 len = strlen(parms[i].name);
4117 if (!strncmp(stp, parms[i].name, len) &&
4118 (*(stp + len) == ':' || *(stp + len) == '=')) {
4119 if (parms[i].val)
4120 *parms[i].val =
4121 simple_strtoul(stp + len + 1, NULL, 0);
4122 else
4123 printk(KERN_WARNING "st: Obsolete parameter %s\n",
4124 parms[i].name);
4125 break;
4126 }
4127 }
4128 if (i >= ARRAY_SIZE(parms))
4129 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
4130 stp);
4131 stp = strchr(stp, ',');
4132 if (stp)
4133 stp++;
4134 }
4135 }
4136
4137 validate_options();
4138
4139 return 1;
4140}
4141
4142__setup("st=", st_setup);
4143
4144#endif
4145
4146static const struct file_operations st_fops =
4147{
4148 .owner = THIS_MODULE,
4149 .read = st_read,
4150 .write = st_write,
4151 .unlocked_ioctl = st_ioctl,
4152#ifdef CONFIG_COMPAT
4153 .compat_ioctl = st_compat_ioctl,
4154#endif
4155 .open = st_open,
4156 .flush = st_flush,
4157 .release = st_release,
4158 .llseek = noop_llseek,
4159};
4160
4161static int create_one_cdev(struct scsi_tape *tape, int mode, int rew)
4162{
4163 int i, error;
4164 dev_t cdev_devno;
4165 struct cdev *cdev;
4166 struct device *dev;
4167 struct st_modedef *STm = &(tape->modes[mode]);
4168 char name[10];
4169 int dev_num = tape->index;
4170
4171 cdev_devno = MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, rew));
4172
4173 cdev = cdev_alloc();
4174 if (!cdev) {
4175 pr_err("st%d: out of memory. Device not attached.\n", dev_num);
4176 error = -ENOMEM;
4177 goto out;
4178 }
4179 cdev->owner = THIS_MODULE;
4180 cdev->ops = &st_fops;
4181 STm->cdevs[rew] = cdev;
4182
4183 error = cdev_add(cdev, cdev_devno, 1);
4184 if (error) {
4185 pr_err("st%d: Can't add %s-rewind mode %d\n", dev_num,
4186 rew ? "non" : "auto", mode);
4187 pr_err("st%d: Device not attached.\n", dev_num);
4188 goto out_free;
4189 }
4190
4191 i = mode << (4 - ST_NBR_MODE_BITS);
4192 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4193 tape->name, st_formats[i]);
4194
4195 dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,
4196 cdev_devno, &tape->modes[mode], "%s", name);
4197 if (IS_ERR(dev)) {
4198 pr_err("st%d: device_create failed\n", dev_num);
4199 error = PTR_ERR(dev);
4200 goto out_free;
4201 }
4202
4203 STm->devs[rew] = dev;
4204
4205 return 0;
4206out_free:
4207 cdev_del(STm->cdevs[rew]);
4208out:
4209 STm->cdevs[rew] = NULL;
4210 STm->devs[rew] = NULL;
4211 return error;
4212}
4213
4214static int create_cdevs(struct scsi_tape *tape)
4215{
4216 int mode, error;
4217 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4218 error = create_one_cdev(tape, mode, 0);
4219 if (error)
4220 return error;
4221 error = create_one_cdev(tape, mode, 1);
4222 if (error)
4223 return error;
4224 }
4225
4226 return sysfs_create_link(&tape->device->sdev_gendev.kobj,
4227 &tape->modes[0].devs[0]->kobj, "tape");
4228}
4229
4230static void remove_cdevs(struct scsi_tape *tape)
4231{
4232 int mode, rew;
4233 sysfs_remove_link(&tape->device->sdev_gendev.kobj, "tape");
4234 for (mode = 0; mode < ST_NBR_MODES; mode++) {
4235 struct st_modedef *STm = &(tape->modes[mode]);
4236 for (rew = 0; rew < 2; rew++) {
4237 if (STm->cdevs[rew])
4238 cdev_del(STm->cdevs[rew]);
4239 if (STm->devs[rew])
4240 device_unregister(STm->devs[rew]);
4241 }
4242 }
4243}
4244
4245static int st_probe(struct device *dev)
4246{
4247 struct scsi_device *SDp = to_scsi_device(dev);
4248 struct scsi_tape *tpnt = NULL;
4249 struct st_modedef *STm;
4250 struct st_partstat *STps;
4251 struct st_buffer *buffer;
4252 int i, error;
4253
4254 if (SDp->type != TYPE_TAPE)
4255 return -ENODEV;
4256 if (st_incompatible(SDp)) {
4257 sdev_printk(KERN_INFO, SDp,
4258 "OnStream tapes are no longer supported;\n");
4259 sdev_printk(KERN_INFO, SDp,
4260 "please mail to linux-scsi@vger.kernel.org.\n");
4261 return -ENODEV;
4262 }
4263
4264 scsi_autopm_get_device(SDp);
4265 i = queue_max_segments(SDp->request_queue);
4266 if (st_max_sg_segs < i)
4267 i = st_max_sg_segs;
4268 buffer = new_tape_buffer(i);
4269 if (buffer == NULL) {
4270 sdev_printk(KERN_ERR, SDp,
4271 "st: Can't allocate new tape buffer. "
4272 "Device not attached.\n");
4273 goto out;
4274 }
4275
4276 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);
4277 if (tpnt == NULL) {
4278 sdev_printk(KERN_ERR, SDp,
4279 "st: Can't allocate device descriptor.\n");
4280 goto out_buffer_free;
4281 }
4282 kref_init(&tpnt->kref);
4283
4284 tpnt->device = SDp;
4285 if (SDp->scsi_level <= 2)
4286 tpnt->tape_type = MT_ISSCSI1;
4287 else
4288 tpnt->tape_type = MT_ISSCSI2;
4289
4290 tpnt->buffer = buffer;
4291 tpnt->buffer->last_SRpnt = NULL;
4292
4293 tpnt->inited = 0;
4294 tpnt->dirty = 0;
4295 tpnt->in_use = 0;
4296 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
4297 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
4298 tpnt->density = 0;
4299 tpnt->do_auto_lock = ST_AUTO_LOCK;
4300 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
4301 tpnt->can_partitions = 0;
4302 tpnt->two_fm = ST_TWO_FM;
4303 tpnt->fast_mteom = ST_FAST_MTEOM;
4304 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
4305 tpnt->sili = ST_SILI;
4306 tpnt->immediate = ST_NOWAIT;
4307 tpnt->immediate_filemark = 0;
4308 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
4309 tpnt->partition = 0;
4310 tpnt->new_partition = 0;
4311 tpnt->nbr_partitions = 0;
4312 blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
4313 tpnt->long_timeout = ST_LONG_TIMEOUT;
4314 tpnt->try_dio = try_direct_io;
4315
4316 for (i = 0; i < ST_NBR_MODES; i++) {
4317 STm = &(tpnt->modes[i]);
4318 STm->defined = 0;
4319 STm->sysv = ST_SYSV;
4320 STm->defaults_for_writes = 0;
4321 STm->do_async_writes = ST_ASYNC_WRITES;
4322 STm->do_buffer_writes = ST_BUFFER_WRITES;
4323 STm->do_read_ahead = ST_READ_AHEAD;
4324 STm->default_compression = ST_DONT_TOUCH;
4325 STm->default_blksize = (-1); /* No forced size */
4326 STm->default_density = (-1); /* No forced density */
4327 STm->tape = tpnt;
4328 }
4329
4330 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4331 STps = &(tpnt->ps[i]);
4332 STps->rw = ST_IDLE;
4333 STps->eof = ST_NOEOF;
4334 STps->at_sm = 0;
4335 STps->last_block_valid = 0;
4336 STps->drv_block = (-1);
4337 STps->drv_file = (-1);
4338 }
4339
4340 tpnt->current_mode = 0;
4341 tpnt->modes[0].defined = 1;
4342
4343 tpnt->density_changed = tpnt->compression_changed =
4344 tpnt->blksize_changed = 0;
4345 mutex_init(&tpnt->lock);
4346
4347 idr_preload(GFP_KERNEL);
4348 spin_lock(&st_index_lock);
4349 error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
4350 spin_unlock(&st_index_lock);
4351 idr_preload_end();
4352 if (error < 0) {
4353 pr_warn("st: idr allocation failed: %d\n", error);
4354 goto out_free_tape;
4355 }
4356 tpnt->index = error;
4357 sprintf(tpnt->name, "st%d", tpnt->index);
4358 tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);
4359 if (tpnt->stats == NULL) {
4360 sdev_printk(KERN_ERR, SDp,
4361 "st: Can't allocate statistics.\n");
4362 goto out_idr_remove;
4363 }
4364
4365 dev_set_drvdata(dev, tpnt);
4366
4367
4368 error = create_cdevs(tpnt);
4369 if (error)
4370 goto out_remove_devs;
4371 scsi_autopm_put_device(SDp);
4372
4373 sdev_printk(KERN_NOTICE, SDp,
4374 "Attached scsi tape %s\n", tpnt->name);
4375 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4376 tpnt->name, tpnt->try_dio ? "yes" : "no",
4377 queue_dma_alignment(SDp->request_queue) + 1);
4378
4379 return 0;
4380
4381out_remove_devs:
4382 remove_cdevs(tpnt);
4383 kfree(tpnt->stats);
4384out_idr_remove:
4385 spin_lock(&st_index_lock);
4386 idr_remove(&st_index_idr, tpnt->index);
4387 spin_unlock(&st_index_lock);
4388out_free_tape:
4389 kfree(tpnt);
4390out_buffer_free:
4391 kfree(buffer);
4392out:
4393 scsi_autopm_put_device(SDp);
4394 return -ENODEV;
4395};
4396
4397
4398static int st_remove(struct device *dev)
4399{
4400 struct scsi_tape *tpnt = dev_get_drvdata(dev);
4401 int index = tpnt->index;
4402
4403 scsi_autopm_get_device(to_scsi_device(dev));
4404 remove_cdevs(tpnt);
4405
4406 mutex_lock(&st_ref_mutex);
4407 kref_put(&tpnt->kref, scsi_tape_release);
4408 mutex_unlock(&st_ref_mutex);
4409 spin_lock(&st_index_lock);
4410 idr_remove(&st_index_idr, index);
4411 spin_unlock(&st_index_lock);
4412 return 0;
4413}
4414
4415/**
4416 * scsi_tape_release - Called to free the Scsi_Tape structure
4417 * @kref: pointer to embedded kref
4418 *
4419 * st_ref_mutex must be held entering this routine. Because it is
4420 * called on last put, you should always use the scsi_tape_get()
4421 * scsi_tape_put() helpers which manipulate the semaphore directly
4422 * and never do a direct kref_put().
4423 **/
4424static void scsi_tape_release(struct kref *kref)
4425{
4426 struct scsi_tape *tpnt = to_scsi_tape(kref);
4427
4428 tpnt->device = NULL;
4429
4430 if (tpnt->buffer) {
4431 normalize_buffer(tpnt->buffer);
4432 kfree(tpnt->buffer->reserved_pages);
4433 kfree(tpnt->buffer);
4434 }
4435
4436 kfree(tpnt->stats);
4437 kfree(tpnt);
4438 return;
4439}
4440
4441static struct class st_sysfs_class = {
4442 .name = "scsi_tape",
4443 .dev_groups = st_dev_groups,
4444};
4445
4446static int __init init_st(void)
4447{
4448 int err;
4449
4450 validate_options();
4451
4452 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4453 verstr, st_fixed_buffer_size, st_max_sg_segs);
4454
4455 debugging = (debug_flag > 0) ? debug_flag : NO_DEBUG;
4456 if (debugging) {
4457 printk(KERN_INFO "st: Debugging enabled debug_flag = %d\n",
4458 debugging);
4459 }
4460
4461 err = class_register(&st_sysfs_class);
4462 if (err) {
4463 pr_err("Unable register sysfs class for SCSI tapes\n");
4464 return err;
4465 }
4466
4467 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4468 ST_MAX_TAPE_ENTRIES, "st");
4469 if (err) {
4470 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4471 SCSI_TAPE_MAJOR);
4472 goto err_class;
4473 }
4474
4475 err = scsi_register_driver(&st_template.gendrv);
4476 if (err)
4477 goto err_chrdev;
4478
4479 return 0;
4480
4481err_chrdev:
4482 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4483 ST_MAX_TAPE_ENTRIES);
4484err_class:
4485 class_unregister(&st_sysfs_class);
4486 return err;
4487}
4488
4489static void __exit exit_st(void)
4490{
4491 scsi_unregister_driver(&st_template.gendrv);
4492 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4493 ST_MAX_TAPE_ENTRIES);
4494 class_unregister(&st_sysfs_class);
4495 idr_destroy(&st_index_idr);
4496 printk(KERN_INFO "st: Unloaded.\n");
4497}
4498
4499module_init(init_st);
4500module_exit(exit_st);
4501
4502
4503/* The sysfs driver interface. Read-only at the moment */
4504static ssize_t try_direct_io_show(struct device_driver *ddp, char *buf)
4505{
4506 return scnprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4507}
4508static DRIVER_ATTR_RO(try_direct_io);
4509
4510static ssize_t fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4511{
4512 return scnprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4513}
4514static DRIVER_ATTR_RO(fixed_buffer_size);
4515
4516static ssize_t max_sg_segs_show(struct device_driver *ddp, char *buf)
4517{
4518 return scnprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4519}
4520static DRIVER_ATTR_RO(max_sg_segs);
4521
4522static ssize_t version_show(struct device_driver *ddd, char *buf)
4523{
4524 return scnprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4525}
4526static DRIVER_ATTR_RO(version);
4527
4528#if DEBUG
4529static ssize_t debug_flag_store(struct device_driver *ddp,
4530 const char *buf, size_t count)
4531{
4532/* We only care what the first byte of the data is the rest is unused.
4533 * if it's a '1' we turn on debug and if it's a '0' we disable it. All
4534 * other values have -EINVAL returned if they are passed in.
4535 */
4536 if (count > 0) {
4537 if (buf[0] == '0') {
4538 debugging = NO_DEBUG;
4539 return count;
4540 } else if (buf[0] == '1') {
4541 debugging = 1;
4542 return count;
4543 }
4544 }
4545 return -EINVAL;
4546}
4547
4548static ssize_t debug_flag_show(struct device_driver *ddp, char *buf)
4549{
4550 return scnprintf(buf, PAGE_SIZE, "%d\n", debugging);
4551}
4552static DRIVER_ATTR_RW(debug_flag);
4553#endif
4554
4555static struct attribute *st_drv_attrs[] = {
4556 &driver_attr_try_direct_io.attr,
4557 &driver_attr_fixed_buffer_size.attr,
4558 &driver_attr_max_sg_segs.attr,
4559 &driver_attr_version.attr,
4560#if DEBUG
4561 &driver_attr_debug_flag.attr,
4562#endif
4563 NULL,
4564};
4565ATTRIBUTE_GROUPS(st_drv);
4566
4567/* The sysfs simple class interface */
4568static ssize_t
4569defined_show(struct device *dev, struct device_attribute *attr, char *buf)
4570{
4571 struct st_modedef *STm = dev_get_drvdata(dev);
4572 ssize_t l = 0;
4573
4574 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4575 return l;
4576}
4577static DEVICE_ATTR_RO(defined);
4578
4579static ssize_t
4580default_blksize_show(struct device *dev, struct device_attribute *attr,
4581 char *buf)
4582{
4583 struct st_modedef *STm = dev_get_drvdata(dev);
4584 ssize_t l = 0;
4585
4586 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4587 return l;
4588}
4589static DEVICE_ATTR_RO(default_blksize);
4590
4591static ssize_t
4592default_density_show(struct device *dev, struct device_attribute *attr,
4593 char *buf)
4594{
4595 struct st_modedef *STm = dev_get_drvdata(dev);
4596 ssize_t l = 0;
4597 char *fmt;
4598
4599 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4600 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4601 return l;
4602}
4603static DEVICE_ATTR_RO(default_density);
4604
4605static ssize_t
4606default_compression_show(struct device *dev, struct device_attribute *attr,
4607 char *buf)
4608{
4609 struct st_modedef *STm = dev_get_drvdata(dev);
4610 ssize_t l = 0;
4611
4612 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4613 return l;
4614}
4615static DEVICE_ATTR_RO(default_compression);
4616
4617static ssize_t
4618options_show(struct device *dev, struct device_attribute *attr, char *buf)
4619{
4620 struct st_modedef *STm = dev_get_drvdata(dev);
4621 struct scsi_tape *STp = STm->tape;
4622 int options;
4623 ssize_t l = 0;
4624
4625 options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
4626 options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
4627 options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
4628 DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
4629 options |= STp->two_fm ? MT_ST_TWO_FM : 0;
4630 options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
4631 options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
4632 options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
4633 options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
4634 options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
4635 options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
4636 options |= STm->sysv ? MT_ST_SYSV : 0;
4637 options |= STp->immediate ? MT_ST_NOWAIT : 0;
4638 options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0;
4639 options |= STp->sili ? MT_ST_SILI : 0;
4640
4641 l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
4642 return l;
4643}
4644static DEVICE_ATTR_RO(options);
4645
4646/* Support for tape stats */
4647
4648/**
4649 * read_cnt_show - return read count - count of reads made from tape drive
4650 * @dev: struct device
4651 * @attr: attribute structure
4652 * @buf: buffer to return formatted data in
4653 */
4654static ssize_t read_cnt_show(struct device *dev,
4655 struct device_attribute *attr, char *buf)
4656{
4657 struct st_modedef *STm = dev_get_drvdata(dev);
4658
4659 return sprintf(buf, "%lld",
4660 (long long)atomic64_read(&STm->tape->stats->read_cnt));
4661}
4662static DEVICE_ATTR_RO(read_cnt);
4663
4664/**
4665 * read_byte_cnt_show - return read byte count - tape drives
4666 * may use blocks less than 512 bytes this gives the raw byte count of
4667 * of data read from the tape drive.
4668 * @dev: struct device
4669 * @attr: attribute structure
4670 * @buf: buffer to return formatted data in
4671 */
4672static ssize_t read_byte_cnt_show(struct device *dev,
4673 struct device_attribute *attr, char *buf)
4674{
4675 struct st_modedef *STm = dev_get_drvdata(dev);
4676
4677 return sprintf(buf, "%lld",
4678 (long long)atomic64_read(&STm->tape->stats->read_byte_cnt));
4679}
4680static DEVICE_ATTR_RO(read_byte_cnt);
4681
4682/**
4683 * read_ns_show - return read ns - overall time spent waiting on reads in ns.
4684 * @dev: struct device
4685 * @attr: attribute structure
4686 * @buf: buffer to return formatted data in
4687 */
4688static ssize_t read_ns_show(struct device *dev,
4689 struct device_attribute *attr, char *buf)
4690{
4691 struct st_modedef *STm = dev_get_drvdata(dev);
4692
4693 return sprintf(buf, "%lld",
4694 (long long)atomic64_read(&STm->tape->stats->tot_read_time));
4695}
4696static DEVICE_ATTR_RO(read_ns);
4697
4698/**
4699 * write_cnt_show - write count - number of user calls
4700 * to write(2) that have written data to tape.
4701 * @dev: struct device
4702 * @attr: attribute structure
4703 * @buf: buffer to return formatted data in
4704 */
4705static ssize_t write_cnt_show(struct device *dev,
4706 struct device_attribute *attr, char *buf)
4707{
4708 struct st_modedef *STm = dev_get_drvdata(dev);
4709
4710 return sprintf(buf, "%lld",
4711 (long long)atomic64_read(&STm->tape->stats->write_cnt));
4712}
4713static DEVICE_ATTR_RO(write_cnt);
4714
4715/**
4716 * write_byte_cnt_show - write byte count - raw count of
4717 * bytes written to tape.
4718 * @dev: struct device
4719 * @attr: attribute structure
4720 * @buf: buffer to return formatted data in
4721 */
4722static ssize_t write_byte_cnt_show(struct device *dev,
4723 struct device_attribute *attr, char *buf)
4724{
4725 struct st_modedef *STm = dev_get_drvdata(dev);
4726
4727 return sprintf(buf, "%lld",
4728 (long long)atomic64_read(&STm->tape->stats->write_byte_cnt));
4729}
4730static DEVICE_ATTR_RO(write_byte_cnt);
4731
4732/**
4733 * write_ns_show - write ns - number of nanoseconds waiting on write
4734 * requests to complete.
4735 * @dev: struct device
4736 * @attr: attribute structure
4737 * @buf: buffer to return formatted data in
4738 */
4739static ssize_t write_ns_show(struct device *dev,
4740 struct device_attribute *attr, char *buf)
4741{
4742 struct st_modedef *STm = dev_get_drvdata(dev);
4743
4744 return sprintf(buf, "%lld",
4745 (long long)atomic64_read(&STm->tape->stats->tot_write_time));
4746}
4747static DEVICE_ATTR_RO(write_ns);
4748
4749/**
4750 * in_flight_show - number of I/Os currently in flight -
4751 * in most cases this will be either 0 or 1. It may be higher if someone
4752 * has also issued other SCSI commands such as via an ioctl.
4753 * @dev: struct device
4754 * @attr: attribute structure
4755 * @buf: buffer to return formatted data in
4756 */
4757static ssize_t in_flight_show(struct device *dev,
4758 struct device_attribute *attr, char *buf)
4759{
4760 struct st_modedef *STm = dev_get_drvdata(dev);
4761
4762 return sprintf(buf, "%lld",
4763 (long long)atomic64_read(&STm->tape->stats->in_flight));
4764}
4765static DEVICE_ATTR_RO(in_flight);
4766
4767/**
4768 * io_ns_show - io wait ns - this is the number of ns spent
4769 * waiting on all I/O to complete. This includes tape movement commands
4770 * such as rewinding, seeking to end of file or tape, it also includes
4771 * read and write. To determine the time spent on tape movement
4772 * subtract the read and write ns from this value.
4773 * @dev: struct device
4774 * @attr: attribute structure
4775 * @buf: buffer to return formatted data in
4776 */
4777static ssize_t io_ns_show(struct device *dev,
4778 struct device_attribute *attr, char *buf)
4779{
4780 struct st_modedef *STm = dev_get_drvdata(dev);
4781
4782 return sprintf(buf, "%lld",
4783 (long long)atomic64_read(&STm->tape->stats->tot_io_time));
4784}
4785static DEVICE_ATTR_RO(io_ns);
4786
4787/**
4788 * other_cnt_show - other io count - this is the number of
4789 * I/O requests other than read and write requests.
4790 * Typically these are tape movement requests but will include driver
4791 * tape movement. This includes only requests issued by the st driver.
4792 * @dev: struct device
4793 * @attr: attribute structure
4794 * @buf: buffer to return formatted data in
4795 */
4796static ssize_t other_cnt_show(struct device *dev,
4797 struct device_attribute *attr, char *buf)
4798{
4799 struct st_modedef *STm = dev_get_drvdata(dev);
4800
4801 return sprintf(buf, "%lld",
4802 (long long)atomic64_read(&STm->tape->stats->other_cnt));
4803}
4804static DEVICE_ATTR_RO(other_cnt);
4805
4806/**
4807 * resid_cnt_show - A count of the number of times we get a residual
4808 * count - this should indicate someone issuing reads larger than the
4809 * block size on tape.
4810 * @dev: struct device
4811 * @attr: attribute structure
4812 * @buf: buffer to return formatted data in
4813 */
4814static ssize_t resid_cnt_show(struct device *dev,
4815 struct device_attribute *attr, char *buf)
4816{
4817 struct st_modedef *STm = dev_get_drvdata(dev);
4818
4819 return sprintf(buf, "%lld",
4820 (long long)atomic64_read(&STm->tape->stats->resid_cnt));
4821}
4822static DEVICE_ATTR_RO(resid_cnt);
4823
4824static struct attribute *st_dev_attrs[] = {
4825 &dev_attr_defined.attr,
4826 &dev_attr_default_blksize.attr,
4827 &dev_attr_default_density.attr,
4828 &dev_attr_default_compression.attr,
4829 &dev_attr_options.attr,
4830 NULL,
4831};
4832
4833static struct attribute *st_stats_attrs[] = {
4834 &dev_attr_read_cnt.attr,
4835 &dev_attr_read_byte_cnt.attr,
4836 &dev_attr_read_ns.attr,
4837 &dev_attr_write_cnt.attr,
4838 &dev_attr_write_byte_cnt.attr,
4839 &dev_attr_write_ns.attr,
4840 &dev_attr_in_flight.attr,
4841 &dev_attr_io_ns.attr,
4842 &dev_attr_other_cnt.attr,
4843 &dev_attr_resid_cnt.attr,
4844 NULL,
4845};
4846
4847static struct attribute_group stats_group = {
4848 .name = "stats",
4849 .attrs = st_stats_attrs,
4850};
4851
4852static struct attribute_group st_group = {
4853 .attrs = st_dev_attrs,
4854};
4855
4856static const struct attribute_group *st_dev_groups[] = {
4857 &st_group,
4858 &stats_group,
4859 NULL,
4860};
4861
4862/* The following functions may be useful for a larger audience. */
4863static int sgl_map_user_pages(struct st_buffer *STbp,
4864 const unsigned int max_pages, unsigned long uaddr,
4865 size_t count, int rw)
4866{
4867 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4868 unsigned long start = uaddr >> PAGE_SHIFT;
4869 const int nr_pages = end - start;
4870 int res, i;
4871 struct page **pages;
4872 struct rq_map_data *mdata = &STbp->map_data;
4873
4874 /* User attempted Overflow! */
4875 if ((uaddr + count) < uaddr)
4876 return -EINVAL;
4877
4878 /* Too big */
4879 if (nr_pages > max_pages)
4880 return -ENOMEM;
4881
4882 /* Hmm? */
4883 if (count == 0)
4884 return 0;
4885
4886 pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
4887 if (pages == NULL)
4888 return -ENOMEM;
4889
4890 /* Try to fault in all of the necessary pages */
4891 /* rw==READ means read from drive, write into memory area */
4892 res = pin_user_pages_fast(uaddr, nr_pages, rw == READ ? FOLL_WRITE : 0,
4893 pages);
4894
4895 /* Errors and no page mapped should return here */
4896 if (res < nr_pages)
4897 goto out_unmap;
4898
4899 for (i=0; i < nr_pages; i++) {
4900 /* FIXME: flush superflous for rw==READ,
4901 * probably wrong function for rw==WRITE
4902 */
4903 flush_dcache_page(pages[i]);
4904 }
4905
4906 mdata->offset = uaddr & ~PAGE_MASK;
4907 STbp->mapped_pages = pages;
4908
4909 return nr_pages;
4910 out_unmap:
4911 if (res > 0) {
4912 unpin_user_pages(pages, res);
4913 res = 0;
4914 }
4915 kfree(pages);
4916 return res;
4917}
4918
4919
4920/* And unmap them... */
4921static int sgl_unmap_user_pages(struct st_buffer *STbp,
4922 const unsigned int nr_pages, int dirtied)
4923{
4924 /* FIXME: cache flush missing for rw==READ */
4925 unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);
4926
4927 kfree(STbp->mapped_pages);
4928 STbp->mapped_pages = NULL;
4929
4930 return 0;
4931}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
4 file Documentation/scsi/st.rst for more information.
5
6 History:
7 Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
8 Contribution and ideas from several people including (in alphabetical
9 order) Klaus Ehrenfried, Eugene Exarevsky, Eric Lee Green, Wolfgang Denk,
10 Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
11 Michael Schaefer, J"org Weule, and Eric Youngdale.
12
13 Copyright 1992 - 2016 Kai Makisara
14 email Kai.Makisara@kolumbus.fi
15
16 Some small formal changes - aeb, 950809
17
18 Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
19 */
20
21static const char *verstr = "20160209";
22
23#include <linux/module.h>
24
25#include <linux/compat.h>
26#include <linux/fs.h>
27#include <linux/kernel.h>
28#include <linux/sched/signal.h>
29#include <linux/mm.h>
30#include <linux/init.h>
31#include <linux/string.h>
32#include <linux/slab.h>
33#include <linux/errno.h>
34#include <linux/mtio.h>
35#include <linux/cdrom.h>
36#include <linux/ioctl.h>
37#include <linux/fcntl.h>
38#include <linux/spinlock.h>
39#include <linux/blkdev.h>
40#include <linux/moduleparam.h>
41#include <linux/cdev.h>
42#include <linux/idr.h>
43#include <linux/delay.h>
44#include <linux/mutex.h>
45
46#include <linux/uaccess.h>
47#include <asm/dma.h>
48#include <asm/unaligned.h>
49
50#include <scsi/scsi.h>
51#include <scsi/scsi_dbg.h>
52#include <scsi/scsi_device.h>
53#include <scsi/scsi_driver.h>
54#include <scsi/scsi_eh.h>
55#include <scsi/scsi_host.h>
56#include <scsi/scsi_ioctl.h>
57#include <scsi/sg.h>
58
59
60/* The driver prints some debugging information on the console if DEBUG
61 is defined and non-zero. */
62#define DEBUG 1
63#define NO_DEBUG 0
64
65#define ST_DEB_MSG KERN_NOTICE
66#if DEBUG
67/* The message level for the debug messages is currently set to KERN_NOTICE
68 so that people can easily see the messages. Later when the debugging messages
69 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
70#define DEB(a) a
71#define DEBC(a) if (debugging) { a ; }
72#else
73#define DEB(a)
74#define DEBC(a)
75#endif
76
77#define ST_KILOBYTE 1024
78
79#include "st_options.h"
80#include "st.h"
81
82static int buffer_kbs;
83static int max_sg_segs;
84static int try_direct_io = TRY_DIRECT_IO;
85static int try_rdio = 1;
86static int try_wdio = 1;
87static int debug_flag;
88
89static struct class st_sysfs_class;
90static const struct attribute_group *st_dev_groups[];
91static const struct attribute_group *st_drv_groups[];
92
93MODULE_AUTHOR("Kai Makisara");
94MODULE_DESCRIPTION("SCSI tape (st) driver");
95MODULE_LICENSE("GPL");
96MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
97MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
98
99/* Set 'perm' (4th argument) to 0 to disable module_param's definition
100 * of sysfs parameters (which module_param doesn't yet support).
101 * Sysfs parameters defined explicitly later.
102 */
103module_param_named(buffer_kbs, buffer_kbs, int, 0);
104MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
105module_param_named(max_sg_segs, max_sg_segs, int, 0);
106MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
107module_param_named(try_direct_io, try_direct_io, int, 0);
108MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
109module_param_named(debug_flag, debug_flag, int, 0);
110MODULE_PARM_DESC(debug_flag, "Enable DEBUG, same as setting debugging=1");
111
112
113/* Extra parameters for testing */
114module_param_named(try_rdio, try_rdio, int, 0);
115MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
116module_param_named(try_wdio, try_wdio, int, 0);
117MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
118
119#ifndef MODULE
120static int write_threshold_kbs; /* retained for compatibility */
121static struct st_dev_parm {
122 char *name;
123 int *val;
124} parms[] __initdata = {
125 {
126 "buffer_kbs", &buffer_kbs
127 },
128 { /* Retained for compatibility with 2.4 */
129 "write_threshold_kbs", &write_threshold_kbs
130 },
131 {
132 "max_sg_segs", NULL
133 },
134 {
135 "try_direct_io", &try_direct_io
136 },
137 {
138 "debug_flag", &debug_flag
139 }
140};
141#endif
142
143/* Restrict the number of modes so that names for all are assigned */
144#if ST_NBR_MODES > 16
145#error "Maximum number of modes is 16"
146#endif
147/* Bit reversed order to get same names for same minors with all
148 mode counts */
149static const char *st_formats[] = {
150 "", "r", "k", "s", "l", "t", "o", "u",
151 "m", "v", "p", "x", "a", "y", "q", "z"};
152
153/* The default definitions have been moved to st_options.h */
154
155#define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
156
157/* The buffer size should fit into the 24 bits for length in the
158 6-byte SCSI read and write commands. */
159#if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
160#error "Buffer size should not exceed (2 << 24 - 1) bytes!"
161#endif
162
163static int debugging = DEBUG;
164
165#define MAX_RETRIES 0
166#define MAX_WRITE_RETRIES 0
167#define MAX_READY_RETRIES 0
168#define NO_TAPE NOT_READY
169
170#define ST_TIMEOUT (900 * HZ)
171#define ST_LONG_TIMEOUT (14000 * HZ)
172
173/* Remove mode bits and auto-rewind bit (7) */
174#define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
175 (iminor(x) & ((1 << ST_MODE_SHIFT)-1)))
176#define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
177
178/* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
179#define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
180 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
181
182/* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
183 24 bits) */
184#define SET_DENS_AND_BLK 0x10001
185
186static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
187static int st_max_sg_segs = ST_MAX_SG;
188
189static int modes_defined;
190
191static int enlarge_buffer(struct st_buffer *, int);
192static void clear_buffer(struct st_buffer *);
193static void normalize_buffer(struct st_buffer *);
194static int append_to_buffer(const char __user *, struct st_buffer *, int);
195static int from_buffer(struct st_buffer *, char __user *, int);
196static void move_buffer_data(struct st_buffer *, int);
197
198static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
199 unsigned long, size_t, int);
200static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
201
202static int st_probe(struct device *);
203static int st_remove(struct device *);
204
205static struct scsi_driver st_template = {
206 .gendrv = {
207 .name = "st",
208 .owner = THIS_MODULE,
209 .probe = st_probe,
210 .remove = st_remove,
211 .groups = st_drv_groups,
212 },
213};
214
215static int st_compression(struct scsi_tape *, int);
216
217static int find_partition(struct scsi_tape *);
218static int switch_partition(struct scsi_tape *);
219
220static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
221
222static void scsi_tape_release(struct kref *);
223
224#define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
225
226static DEFINE_MUTEX(st_ref_mutex);
227static DEFINE_SPINLOCK(st_index_lock);
228static DEFINE_SPINLOCK(st_use_lock);
229static DEFINE_IDR(st_index_idr);
230
231
232
233#ifndef SIGS_FROM_OSST
234#define SIGS_FROM_OSST \
235 {"OnStream", "SC-", "", "osst"}, \
236 {"OnStream", "DI-", "", "osst"}, \
237 {"OnStream", "DP-", "", "osst"}, \
238 {"OnStream", "USB", "", "osst"}, \
239 {"OnStream", "FW-", "", "osst"}
240#endif
241
242static struct scsi_tape *scsi_tape_get(int dev)
243{
244 struct scsi_tape *STp = NULL;
245
246 mutex_lock(&st_ref_mutex);
247 spin_lock(&st_index_lock);
248
249 STp = idr_find(&st_index_idr, dev);
250 if (!STp) goto out;
251
252 kref_get(&STp->kref);
253
254 if (!STp->device)
255 goto out_put;
256
257 if (scsi_device_get(STp->device))
258 goto out_put;
259
260 goto out;
261
262out_put:
263 kref_put(&STp->kref, scsi_tape_release);
264 STp = NULL;
265out:
266 spin_unlock(&st_index_lock);
267 mutex_unlock(&st_ref_mutex);
268 return STp;
269}
270
271static void scsi_tape_put(struct scsi_tape *STp)
272{
273 struct scsi_device *sdev = STp->device;
274
275 mutex_lock(&st_ref_mutex);
276 kref_put(&STp->kref, scsi_tape_release);
277 scsi_device_put(sdev);
278 mutex_unlock(&st_ref_mutex);
279}
280
281struct st_reject_data {
282 char *vendor;
283 char *model;
284 char *rev;
285 char *driver_hint; /* Name of the correct driver, NULL if unknown */
286};
287
288static struct st_reject_data reject_list[] = {
289 /* {"XXX", "Yy-", "", NULL}, example */
290 SIGS_FROM_OSST,
291 {NULL, }};
292
293/* If the device signature is on the list of incompatible drives, the
294 function returns a pointer to the name of the correct driver (if known) */
295static char * st_incompatible(struct scsi_device* SDp)
296{
297 struct st_reject_data *rp;
298
299 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
300 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
301 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
302 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
303 if (rp->driver_hint)
304 return rp->driver_hint;
305 else
306 return "unknown";
307 }
308 return NULL;
309}
310
311
312static inline char *tape_name(struct scsi_tape *tape)
313{
314 return tape->disk->disk_name;
315}
316
317#define st_printk(prefix, t, fmt, a...) \
318 sdev_prefix_printk(prefix, (t)->device, tape_name(t), fmt, ##a)
319#ifdef DEBUG
320#define DEBC_printk(t, fmt, a...) \
321 if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }
322#else
323#define DEBC_printk(t, fmt, a...)
324#endif
325
326static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
327{
328 const u8 *ucp;
329 const u8 *sense = SRpnt->sense;
330
331 s->have_sense = scsi_normalize_sense(SRpnt->sense,
332 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
333 s->flags = 0;
334
335 if (s->have_sense) {
336 s->deferred = 0;
337 s->remainder_valid =
338 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
339 switch (sense[0] & 0x7f) {
340 case 0x71:
341 s->deferred = 1;
342 fallthrough;
343 case 0x70:
344 s->fixed_format = 1;
345 s->flags = sense[2] & 0xe0;
346 break;
347 case 0x73:
348 s->deferred = 1;
349 fallthrough;
350 case 0x72:
351 s->fixed_format = 0;
352 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
353 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
354 break;
355 }
356 }
357}
358
359
360/* Convert the result to success code */
361static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
362{
363 int result = SRpnt->result;
364 u8 scode;
365 DEB(const char *stp;)
366 char *name = tape_name(STp);
367 struct st_cmdstatus *cmdstatp;
368
369 if (!result)
370 return 0;
371
372 cmdstatp = &STp->buffer->cmdstat;
373 st_analyze_sense(SRpnt, cmdstatp);
374
375 if (cmdstatp->have_sense)
376 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
377 else
378 scode = 0;
379
380 DEB(
381 if (debugging) {
382 st_printk(ST_DEB_MSG, STp,
383 "Error: %x, cmd: %x %x %x %x %x %x\n", result,
384 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
385 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
386 if (cmdstatp->have_sense)
387 __scsi_print_sense(STp->device, name,
388 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
389 } ) /* end DEB */
390 if (!debugging) { /* Abnormal conditions for tape */
391 if (!cmdstatp->have_sense)
392 st_printk(KERN_WARNING, STp,
393 "Error %x (driver bt 0, host bt 0x%x).\n",
394 result, host_byte(result));
395 else if (cmdstatp->have_sense &&
396 scode != NO_SENSE &&
397 scode != RECOVERED_ERROR &&
398 /* scode != UNIT_ATTENTION && */
399 scode != BLANK_CHECK &&
400 scode != VOLUME_OVERFLOW &&
401 SRpnt->cmd[0] != MODE_SENSE &&
402 SRpnt->cmd[0] != TEST_UNIT_READY) {
403
404 __scsi_print_sense(STp->device, name,
405 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
406 }
407 }
408
409 if (cmdstatp->fixed_format &&
410 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
411 if (STp->cln_sense_value)
412 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
413 STp->cln_sense_mask) == STp->cln_sense_value);
414 else
415 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
416 STp->cln_sense_mask) != 0);
417 }
418 if (cmdstatp->have_sense &&
419 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
420 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
421
422 STp->pos_unknown |= STp->device->was_reset;
423
424 if (cmdstatp->have_sense &&
425 scode == RECOVERED_ERROR
426#if ST_RECOVERED_WRITE_FATAL
427 && SRpnt->cmd[0] != WRITE_6
428 && SRpnt->cmd[0] != WRITE_FILEMARKS
429#endif
430 ) {
431 STp->recover_count++;
432 STp->recover_reg++;
433
434 DEB(
435 if (debugging) {
436 if (SRpnt->cmd[0] == READ_6)
437 stp = "read";
438 else if (SRpnt->cmd[0] == WRITE_6)
439 stp = "write";
440 else
441 stp = "ioctl";
442 st_printk(ST_DEB_MSG, STp,
443 "Recovered %s error (%d).\n",
444 stp, STp->recover_count);
445 } ) /* end DEB */
446
447 if (cmdstatp->flags == 0)
448 return 0;
449 }
450 return (-EIO);
451}
452
453static struct st_request *st_allocate_request(struct scsi_tape *stp)
454{
455 struct st_request *streq;
456
457 streq = kzalloc(sizeof(*streq), GFP_KERNEL);
458 if (streq)
459 streq->stp = stp;
460 else {
461 st_printk(KERN_ERR, stp,
462 "Can't get SCSI request.\n");
463 if (signal_pending(current))
464 stp->buffer->syscall_result = -EINTR;
465 else
466 stp->buffer->syscall_result = -EBUSY;
467 }
468
469 return streq;
470}
471
472static void st_release_request(struct st_request *streq)
473{
474 kfree(streq);
475}
476
477static void st_do_stats(struct scsi_tape *STp, struct request *req)
478{
479 ktime_t now;
480
481 now = ktime_get();
482 if (scsi_req(req)->cmd[0] == WRITE_6) {
483 now = ktime_sub(now, STp->stats->write_time);
484 atomic64_add(ktime_to_ns(now), &STp->stats->tot_write_time);
485 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
486 atomic64_inc(&STp->stats->write_cnt);
487 if (scsi_req(req)->result) {
488 atomic64_add(atomic_read(&STp->stats->last_write_size)
489 - STp->buffer->cmdstat.residual,
490 &STp->stats->write_byte_cnt);
491 if (STp->buffer->cmdstat.residual > 0)
492 atomic64_inc(&STp->stats->resid_cnt);
493 } else
494 atomic64_add(atomic_read(&STp->stats->last_write_size),
495 &STp->stats->write_byte_cnt);
496 } else if (scsi_req(req)->cmd[0] == READ_6) {
497 now = ktime_sub(now, STp->stats->read_time);
498 atomic64_add(ktime_to_ns(now), &STp->stats->tot_read_time);
499 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
500 atomic64_inc(&STp->stats->read_cnt);
501 if (scsi_req(req)->result) {
502 atomic64_add(atomic_read(&STp->stats->last_read_size)
503 - STp->buffer->cmdstat.residual,
504 &STp->stats->read_byte_cnt);
505 if (STp->buffer->cmdstat.residual > 0)
506 atomic64_inc(&STp->stats->resid_cnt);
507 } else
508 atomic64_add(atomic_read(&STp->stats->last_read_size),
509 &STp->stats->read_byte_cnt);
510 } else {
511 now = ktime_sub(now, STp->stats->other_time);
512 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
513 atomic64_inc(&STp->stats->other_cnt);
514 }
515 atomic64_dec(&STp->stats->in_flight);
516}
517
518static void st_scsi_execute_end(struct request *req, blk_status_t status)
519{
520 struct st_request *SRpnt = req->end_io_data;
521 struct scsi_request *rq = scsi_req(req);
522 struct scsi_tape *STp = SRpnt->stp;
523 struct bio *tmp;
524
525 STp->buffer->cmdstat.midlevel_result = SRpnt->result = rq->result;
526 STp->buffer->cmdstat.residual = rq->resid_len;
527
528 st_do_stats(STp, req);
529
530 tmp = SRpnt->bio;
531 if (rq->sense_len)
532 memcpy(SRpnt->sense, rq->sense, SCSI_SENSE_BUFFERSIZE);
533 if (SRpnt->waiting)
534 complete(SRpnt->waiting);
535
536 blk_rq_unmap_user(tmp);
537 blk_put_request(req);
538}
539
540static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
541 int data_direction, void *buffer, unsigned bufflen,
542 int timeout, int retries)
543{
544 struct request *req;
545 struct scsi_request *rq;
546 struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
547 int err = 0;
548 struct scsi_tape *STp = SRpnt->stp;
549
550 req = blk_get_request(SRpnt->stp->device->request_queue,
551 data_direction == DMA_TO_DEVICE ?
552 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
553 if (IS_ERR(req))
554 return PTR_ERR(req);
555 rq = scsi_req(req);
556 req->rq_flags |= RQF_QUIET;
557
558 mdata->null_mapped = 1;
559
560 if (bufflen) {
561 err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
562 GFP_KERNEL);
563 if (err) {
564 blk_put_request(req);
565 return err;
566 }
567 }
568
569 atomic64_inc(&STp->stats->in_flight);
570 if (cmd[0] == WRITE_6) {
571 atomic_set(&STp->stats->last_write_size, bufflen);
572 STp->stats->write_time = ktime_get();
573 } else if (cmd[0] == READ_6) {
574 atomic_set(&STp->stats->last_read_size, bufflen);
575 STp->stats->read_time = ktime_get();
576 } else {
577 STp->stats->other_time = ktime_get();
578 }
579
580 SRpnt->bio = req->bio;
581 rq->cmd_len = COMMAND_SIZE(cmd[0]);
582 memset(rq->cmd, 0, BLK_MAX_CDB);
583 memcpy(rq->cmd, cmd, rq->cmd_len);
584 req->timeout = timeout;
585 rq->retries = retries;
586 req->end_io_data = SRpnt;
587
588 blk_execute_rq_nowait(NULL, req, 1, st_scsi_execute_end);
589 return 0;
590}
591
592/* Do the scsi command. Waits until command performed if do_wait is true.
593 Otherwise write_behind_check() is used to check that the command
594 has finished. */
595static struct st_request *
596st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
597 int bytes, int direction, int timeout, int retries, int do_wait)
598{
599 struct completion *waiting;
600 struct rq_map_data *mdata = &STp->buffer->map_data;
601 int ret;
602
603 /* if async, make sure there's no command outstanding */
604 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
605 st_printk(KERN_ERR, STp,
606 "Async command already active.\n");
607 if (signal_pending(current))
608 (STp->buffer)->syscall_result = (-EINTR);
609 else
610 (STp->buffer)->syscall_result = (-EBUSY);
611 return NULL;
612 }
613
614 if (!SRpnt) {
615 SRpnt = st_allocate_request(STp);
616 if (!SRpnt)
617 return NULL;
618 }
619
620 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
621 which IO is outstanding. It's nulled out when the IO completes. */
622 if (!do_wait)
623 (STp->buffer)->last_SRpnt = SRpnt;
624
625 waiting = &STp->wait;
626 init_completion(waiting);
627 SRpnt->waiting = waiting;
628
629 if (STp->buffer->do_dio) {
630 mdata->page_order = 0;
631 mdata->nr_entries = STp->buffer->sg_segs;
632 mdata->pages = STp->buffer->mapped_pages;
633 } else {
634 mdata->page_order = STp->buffer->reserved_page_order;
635 mdata->nr_entries =
636 DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
637 mdata->pages = STp->buffer->reserved_pages;
638 mdata->offset = 0;
639 }
640
641 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
642 STp->buffer->cmdstat.have_sense = 0;
643 STp->buffer->syscall_result = 0;
644
645 ret = st_scsi_execute(SRpnt, cmd, direction, NULL, bytes, timeout,
646 retries);
647 if (ret) {
648 /* could not allocate the buffer or request was too large */
649 (STp->buffer)->syscall_result = (-EBUSY);
650 (STp->buffer)->last_SRpnt = NULL;
651 } else if (do_wait) {
652 wait_for_completion(waiting);
653 SRpnt->waiting = NULL;
654 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
655 }
656
657 return SRpnt;
658}
659
660
661/* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
662 write has been correct but EOM early warning reached, -EIO if write ended in
663 error or zero if write successful. Asynchronous writes are used only in
664 variable block mode. */
665static int write_behind_check(struct scsi_tape * STp)
666{
667 int retval = 0;
668 struct st_buffer *STbuffer;
669 struct st_partstat *STps;
670 struct st_cmdstatus *cmdstatp;
671 struct st_request *SRpnt;
672
673 STbuffer = STp->buffer;
674 if (!STbuffer->writing)
675 return 0;
676
677 DEB(
678 if (STp->write_pending)
679 STp->nbr_waits++;
680 else
681 STp->nbr_finished++;
682 ) /* end DEB */
683
684 wait_for_completion(&(STp->wait));
685 SRpnt = STbuffer->last_SRpnt;
686 STbuffer->last_SRpnt = NULL;
687 SRpnt->waiting = NULL;
688
689 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
690 st_release_request(SRpnt);
691
692 STbuffer->buffer_bytes -= STbuffer->writing;
693 STps = &(STp->ps[STp->partition]);
694 if (STps->drv_block >= 0) {
695 if (STp->block_size == 0)
696 STps->drv_block++;
697 else
698 STps->drv_block += STbuffer->writing / STp->block_size;
699 }
700
701 cmdstatp = &STbuffer->cmdstat;
702 if (STbuffer->syscall_result) {
703 retval = -EIO;
704 if (cmdstatp->have_sense && !cmdstatp->deferred &&
705 (cmdstatp->flags & SENSE_EOM) &&
706 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
707 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
708 /* EOM at write-behind, has all data been written? */
709 if (!cmdstatp->remainder_valid ||
710 cmdstatp->uremainder64 == 0)
711 retval = -ENOSPC;
712 }
713 if (retval == -EIO)
714 STps->drv_block = -1;
715 }
716 STbuffer->writing = 0;
717
718 DEB(if (debugging && retval)
719 st_printk(ST_DEB_MSG, STp,
720 "Async write error %x, return value %d.\n",
721 STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
722
723 return retval;
724}
725
726
727/* Step over EOF if it has been inadvertently crossed (ioctl not used because
728 it messes up the block number). */
729static int cross_eof(struct scsi_tape * STp, int forward)
730{
731 struct st_request *SRpnt;
732 unsigned char cmd[MAX_COMMAND_SIZE];
733
734 cmd[0] = SPACE;
735 cmd[1] = 0x01; /* Space FileMarks */
736 if (forward) {
737 cmd[2] = cmd[3] = 0;
738 cmd[4] = 1;
739 } else
740 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
741 cmd[5] = 0;
742
743 DEBC_printk(STp, "Stepping over filemark %s.\n",
744 forward ? "forward" : "backward");
745
746 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
747 STp->device->request_queue->rq_timeout,
748 MAX_RETRIES, 1);
749 if (!SRpnt)
750 return (STp->buffer)->syscall_result;
751
752 st_release_request(SRpnt);
753 SRpnt = NULL;
754
755 if ((STp->buffer)->cmdstat.midlevel_result != 0)
756 st_printk(KERN_ERR, STp,
757 "Stepping over filemark %s failed.\n",
758 forward ? "forward" : "backward");
759
760 return (STp->buffer)->syscall_result;
761}
762
763
764/* Flush the write buffer (never need to write if variable blocksize). */
765static int st_flush_write_buffer(struct scsi_tape * STp)
766{
767 int transfer, blks;
768 int result;
769 unsigned char cmd[MAX_COMMAND_SIZE];
770 struct st_request *SRpnt;
771 struct st_partstat *STps;
772
773 result = write_behind_check(STp);
774 if (result)
775 return result;
776
777 result = 0;
778 if (STp->dirty == 1) {
779
780 transfer = STp->buffer->buffer_bytes;
781 DEBC_printk(STp, "Flushing %d bytes.\n", transfer);
782
783 memset(cmd, 0, MAX_COMMAND_SIZE);
784 cmd[0] = WRITE_6;
785 cmd[1] = 1;
786 blks = transfer / STp->block_size;
787 cmd[2] = blks >> 16;
788 cmd[3] = blks >> 8;
789 cmd[4] = blks;
790
791 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
792 STp->device->request_queue->rq_timeout,
793 MAX_WRITE_RETRIES, 1);
794 if (!SRpnt)
795 return (STp->buffer)->syscall_result;
796
797 STps = &(STp->ps[STp->partition]);
798 if ((STp->buffer)->syscall_result != 0) {
799 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
800
801 if (cmdstatp->have_sense && !cmdstatp->deferred &&
802 (cmdstatp->flags & SENSE_EOM) &&
803 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
804 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
805 (!cmdstatp->remainder_valid ||
806 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
807 STp->dirty = 0;
808 (STp->buffer)->buffer_bytes = 0;
809 if (STps->drv_block >= 0)
810 STps->drv_block += blks;
811 result = (-ENOSPC);
812 } else {
813 st_printk(KERN_ERR, STp, "Error on flush.\n");
814 STps->drv_block = (-1);
815 result = (-EIO);
816 }
817 } else {
818 if (STps->drv_block >= 0)
819 STps->drv_block += blks;
820 STp->dirty = 0;
821 (STp->buffer)->buffer_bytes = 0;
822 }
823 st_release_request(SRpnt);
824 SRpnt = NULL;
825 }
826 return result;
827}
828
829
830/* Flush the tape buffer. The tape will be positioned correctly unless
831 seek_next is true. */
832static int flush_buffer(struct scsi_tape *STp, int seek_next)
833{
834 int backspace, result;
835 struct st_partstat *STps;
836
837 /*
838 * If there was a bus reset, block further access
839 * to this device.
840 */
841 if (STp->pos_unknown)
842 return (-EIO);
843
844 if (STp->ready != ST_READY)
845 return 0;
846 STps = &(STp->ps[STp->partition]);
847 if (STps->rw == ST_WRITING) /* Writing */
848 return st_flush_write_buffer(STp);
849
850 if (STp->block_size == 0)
851 return 0;
852
853 backspace = ((STp->buffer)->buffer_bytes +
854 (STp->buffer)->read_pointer) / STp->block_size -
855 ((STp->buffer)->read_pointer + STp->block_size - 1) /
856 STp->block_size;
857 (STp->buffer)->buffer_bytes = 0;
858 (STp->buffer)->read_pointer = 0;
859 result = 0;
860 if (!seek_next) {
861 if (STps->eof == ST_FM_HIT) {
862 result = cross_eof(STp, 0); /* Back over the EOF hit */
863 if (!result)
864 STps->eof = ST_NOEOF;
865 else {
866 if (STps->drv_file >= 0)
867 STps->drv_file++;
868 STps->drv_block = 0;
869 }
870 }
871 if (!result && backspace > 0)
872 result = st_int_ioctl(STp, MTBSR, backspace);
873 } else if (STps->eof == ST_FM_HIT) {
874 if (STps->drv_file >= 0)
875 STps->drv_file++;
876 STps->drv_block = 0;
877 STps->eof = ST_NOEOF;
878 }
879 return result;
880
881}
882
883/* Set the mode parameters */
884static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
885{
886 int set_it = 0;
887 unsigned long arg;
888
889 if (!STp->density_changed &&
890 STm->default_density >= 0 &&
891 STm->default_density != STp->density) {
892 arg = STm->default_density;
893 set_it = 1;
894 } else
895 arg = STp->density;
896 arg <<= MT_ST_DENSITY_SHIFT;
897 if (!STp->blksize_changed &&
898 STm->default_blksize >= 0 &&
899 STm->default_blksize != STp->block_size) {
900 arg |= STm->default_blksize;
901 set_it = 1;
902 } else
903 arg |= STp->block_size;
904 if (set_it &&
905 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
906 st_printk(KERN_WARNING, STp,
907 "Can't set default block size to %d bytes "
908 "and density %x.\n",
909 STm->default_blksize, STm->default_density);
910 if (modes_defined)
911 return (-EINVAL);
912 }
913 return 0;
914}
915
916
917/* Lock or unlock the drive door. Don't use when st_request allocated. */
918static int do_door_lock(struct scsi_tape * STp, int do_lock)
919{
920 int retval;
921
922 DEBC_printk(STp, "%socking drive door.\n", do_lock ? "L" : "Unl");
923
924 retval = scsi_set_medium_removal(STp->device,
925 do_lock ? SCSI_REMOVAL_PREVENT : SCSI_REMOVAL_ALLOW);
926 if (!retval)
927 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
928 else
929 STp->door_locked = ST_LOCK_FAILS;
930 return retval;
931}
932
933
934/* Set the internal state after reset */
935static void reset_state(struct scsi_tape *STp)
936{
937 int i;
938 struct st_partstat *STps;
939
940 STp->pos_unknown = 0;
941 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
942 STps = &(STp->ps[i]);
943 STps->rw = ST_IDLE;
944 STps->eof = ST_NOEOF;
945 STps->at_sm = 0;
946 STps->last_block_valid = 0;
947 STps->drv_block = -1;
948 STps->drv_file = -1;
949 }
950 if (STp->can_partitions) {
951 STp->partition = find_partition(STp);
952 if (STp->partition < 0)
953 STp->partition = 0;
954 STp->new_partition = STp->partition;
955 }
956}
957
958/* Test if the drive is ready. Returns either one of the codes below or a negative system
959 error code. */
960#define CHKRES_READY 0
961#define CHKRES_NEW_SESSION 1
962#define CHKRES_NOT_READY 2
963#define CHKRES_NO_TAPE 3
964
965#define MAX_ATTENTIONS 10
966
967static int test_ready(struct scsi_tape *STp, int do_wait)
968{
969 int attentions, waits, max_wait, scode;
970 int retval = CHKRES_READY, new_session = 0;
971 unsigned char cmd[MAX_COMMAND_SIZE];
972 struct st_request *SRpnt = NULL;
973 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
974
975 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
976
977 for (attentions=waits=0; ; ) {
978 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
979 cmd[0] = TEST_UNIT_READY;
980 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
981 STp->long_timeout, MAX_READY_RETRIES, 1);
982
983 if (!SRpnt) {
984 retval = (STp->buffer)->syscall_result;
985 break;
986 }
987
988 if (cmdstatp->have_sense) {
989
990 scode = cmdstatp->sense_hdr.sense_key;
991
992 if (scode == UNIT_ATTENTION) { /* New media? */
993 new_session = 1;
994 if (attentions < MAX_ATTENTIONS) {
995 attentions++;
996 continue;
997 }
998 else {
999 retval = (-EIO);
1000 break;
1001 }
1002 }
1003
1004 if (scode == NOT_READY) {
1005 if (waits < max_wait) {
1006 if (msleep_interruptible(1000)) {
1007 retval = (-EINTR);
1008 break;
1009 }
1010 waits++;
1011 continue;
1012 }
1013 else {
1014 if ((STp->device)->scsi_level >= SCSI_2 &&
1015 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
1016 retval = CHKRES_NO_TAPE;
1017 else
1018 retval = CHKRES_NOT_READY;
1019 break;
1020 }
1021 }
1022 }
1023
1024 retval = (STp->buffer)->syscall_result;
1025 if (!retval)
1026 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
1027 break;
1028 }
1029
1030 if (SRpnt != NULL)
1031 st_release_request(SRpnt);
1032 return retval;
1033}
1034
1035
1036/* See if the drive is ready and gather information about the tape. Return values:
1037 < 0 negative error code from errno.h
1038 0 drive ready
1039 1 drive not ready (possibly no tape)
1040*/
1041static int check_tape(struct scsi_tape *STp, struct file *filp)
1042{
1043 int i, retval, new_session = 0, do_wait;
1044 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
1045 unsigned short st_flags = filp->f_flags;
1046 struct st_request *SRpnt = NULL;
1047 struct st_modedef *STm;
1048 struct st_partstat *STps;
1049 struct inode *inode = file_inode(filp);
1050 int mode = TAPE_MODE(inode);
1051
1052 STp->ready = ST_READY;
1053
1054 if (mode != STp->current_mode) {
1055 DEBC_printk(STp, "Mode change from %d to %d.\n",
1056 STp->current_mode, mode);
1057 new_session = 1;
1058 STp->current_mode = mode;
1059 }
1060 STm = &(STp->modes[STp->current_mode]);
1061
1062 saved_cleaning = STp->cleaning_req;
1063 STp->cleaning_req = 0;
1064
1065 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
1066 retval = test_ready(STp, do_wait);
1067
1068 if (retval < 0)
1069 goto err_out;
1070
1071 if (retval == CHKRES_NEW_SESSION) {
1072 STp->pos_unknown = 0;
1073 STp->partition = STp->new_partition = 0;
1074 if (STp->can_partitions)
1075 STp->nbr_partitions = 1; /* This guess will be updated later
1076 if necessary */
1077 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1078 STps = &(STp->ps[i]);
1079 STps->rw = ST_IDLE;
1080 STps->eof = ST_NOEOF;
1081 STps->at_sm = 0;
1082 STps->last_block_valid = 0;
1083 STps->drv_block = 0;
1084 STps->drv_file = 0;
1085 }
1086 new_session = 1;
1087 }
1088 else {
1089 STp->cleaning_req |= saved_cleaning;
1090
1091 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
1092 if (retval == CHKRES_NO_TAPE)
1093 STp->ready = ST_NO_TAPE;
1094 else
1095 STp->ready = ST_NOT_READY;
1096
1097 STp->density = 0; /* Clear the erroneous "residue" */
1098 STp->write_prot = 0;
1099 STp->block_size = 0;
1100 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
1101 STp->partition = STp->new_partition = 0;
1102 STp->door_locked = ST_UNLOCKED;
1103 return CHKRES_NOT_READY;
1104 }
1105 }
1106
1107 if (STp->omit_blklims)
1108 STp->min_block = STp->max_block = (-1);
1109 else {
1110 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1111 cmd[0] = READ_BLOCK_LIMITS;
1112
1113 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
1114 STp->device->request_queue->rq_timeout,
1115 MAX_READY_RETRIES, 1);
1116 if (!SRpnt) {
1117 retval = (STp->buffer)->syscall_result;
1118 goto err_out;
1119 }
1120
1121 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1122 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
1123 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1124 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1125 (STp->buffer)->b_data[5];
1126 if ( DEB( debugging || ) !STp->inited)
1127 st_printk(KERN_INFO, STp,
1128 "Block limits %d - %d bytes.\n",
1129 STp->min_block, STp->max_block);
1130 } else {
1131 STp->min_block = STp->max_block = (-1);
1132 DEBC_printk(STp, "Can't read block limits.\n");
1133 }
1134 }
1135
1136 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1137 cmd[0] = MODE_SENSE;
1138 cmd[4] = 12;
1139
1140 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1141 STp->device->request_queue->rq_timeout,
1142 MAX_READY_RETRIES, 1);
1143 if (!SRpnt) {
1144 retval = (STp->buffer)->syscall_result;
1145 goto err_out;
1146 }
1147
1148 if ((STp->buffer)->syscall_result != 0) {
1149 DEBC_printk(STp, "No Mode Sense.\n");
1150 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1151 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1152 STp->drv_write_prot = 0;
1153 } else {
1154 DEBC_printk(STp,"Mode sense. Length %d, "
1155 "medium %x, WBS %x, BLL %d\n",
1156 (STp->buffer)->b_data[0],
1157 (STp->buffer)->b_data[1],
1158 (STp->buffer)->b_data[2],
1159 (STp->buffer)->b_data[3]);
1160
1161 if ((STp->buffer)->b_data[3] >= 8) {
1162 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1163 STp->density = (STp->buffer)->b_data[4];
1164 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1165 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1166 DEBC_printk(STp, "Density %x, tape length: %x, "
1167 "drv buffer: %d\n",
1168 STp->density,
1169 (STp->buffer)->b_data[5] * 65536 +
1170 (STp->buffer)->b_data[6] * 256 +
1171 (STp->buffer)->b_data[7],
1172 STp->drv_buffer);
1173 }
1174 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1175 if (!STp->drv_buffer && STp->immediate_filemark) {
1176 st_printk(KERN_WARNING, STp,
1177 "non-buffered tape: disabling "
1178 "writing immediate filemarks\n");
1179 STp->immediate_filemark = 0;
1180 }
1181 }
1182 st_release_request(SRpnt);
1183 SRpnt = NULL;
1184 STp->inited = 1;
1185
1186 if (STp->block_size > 0)
1187 (STp->buffer)->buffer_blocks =
1188 (STp->buffer)->buffer_size / STp->block_size;
1189 else
1190 (STp->buffer)->buffer_blocks = 1;
1191 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1192
1193 DEBC_printk(STp, "Block size: %d, buffer size: %d (%d blocks).\n",
1194 STp->block_size, (STp->buffer)->buffer_size,
1195 (STp->buffer)->buffer_blocks);
1196
1197 if (STp->drv_write_prot) {
1198 STp->write_prot = 1;
1199
1200 DEBC_printk(STp, "Write protected\n");
1201
1202 if (do_wait &&
1203 ((st_flags & O_ACCMODE) == O_WRONLY ||
1204 (st_flags & O_ACCMODE) == O_RDWR)) {
1205 retval = (-EROFS);
1206 goto err_out;
1207 }
1208 }
1209
1210 if (STp->can_partitions && STp->nbr_partitions < 1) {
1211 /* This code is reached when the device is opened for the first time
1212 after the driver has been initialized with tape in the drive and the
1213 partition support has been enabled. */
1214 DEBC_printk(STp, "Updating partition number in status.\n");
1215 if ((STp->partition = find_partition(STp)) < 0) {
1216 retval = STp->partition;
1217 goto err_out;
1218 }
1219 STp->new_partition = STp->partition;
1220 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1221 }
1222
1223 if (new_session) { /* Change the drive parameters for the new mode */
1224 STp->density_changed = STp->blksize_changed = 0;
1225 STp->compression_changed = 0;
1226 if (!(STm->defaults_for_writes) &&
1227 (retval = set_mode_densblk(STp, STm)) < 0)
1228 goto err_out;
1229
1230 if (STp->default_drvbuffer != 0xff) {
1231 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1232 st_printk(KERN_WARNING, STp,
1233 "Can't set default drive "
1234 "buffering to %d.\n",
1235 STp->default_drvbuffer);
1236 }
1237 }
1238
1239 return CHKRES_READY;
1240
1241 err_out:
1242 return retval;
1243}
1244
1245
1246 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1247 module count. */
1248static int st_open(struct inode *inode, struct file *filp)
1249{
1250 int i, retval = (-EIO);
1251 int resumed = 0;
1252 struct scsi_tape *STp;
1253 struct st_partstat *STps;
1254 int dev = TAPE_NR(inode);
1255
1256 /*
1257 * We really want to do nonseekable_open(inode, filp); here, but some
1258 * versions of tar incorrectly call lseek on tapes and bail out if that
1259 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1260 */
1261 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1262
1263 if (!(STp = scsi_tape_get(dev))) {
1264 return -ENXIO;
1265 }
1266
1267 filp->private_data = STp;
1268
1269 spin_lock(&st_use_lock);
1270 if (STp->in_use) {
1271 spin_unlock(&st_use_lock);
1272 DEBC_printk(STp, "Device already in use.\n");
1273 scsi_tape_put(STp);
1274 return (-EBUSY);
1275 }
1276
1277 STp->in_use = 1;
1278 spin_unlock(&st_use_lock);
1279 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1280
1281 if (scsi_autopm_get_device(STp->device) < 0) {
1282 retval = -EIO;
1283 goto err_out;
1284 }
1285 resumed = 1;
1286 if (!scsi_block_when_processing_errors(STp->device)) {
1287 retval = (-ENXIO);
1288 goto err_out;
1289 }
1290
1291 /* See that we have at least a one page buffer available */
1292 if (!enlarge_buffer(STp->buffer, PAGE_SIZE)) {
1293 st_printk(KERN_WARNING, STp,
1294 "Can't allocate one page tape buffer.\n");
1295 retval = (-EOVERFLOW);
1296 goto err_out;
1297 }
1298
1299 (STp->buffer)->cleared = 0;
1300 (STp->buffer)->writing = 0;
1301 (STp->buffer)->syscall_result = 0;
1302
1303 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1304
1305 STp->dirty = 0;
1306 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1307 STps = &(STp->ps[i]);
1308 STps->rw = ST_IDLE;
1309 }
1310 STp->try_dio_now = STp->try_dio;
1311 STp->recover_count = 0;
1312 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1313 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
1314
1315 retval = check_tape(STp, filp);
1316 if (retval < 0)
1317 goto err_out;
1318 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1319 retval != CHKRES_READY) {
1320 if (STp->ready == NO_TAPE)
1321 retval = (-ENOMEDIUM);
1322 else
1323 retval = (-EIO);
1324 goto err_out;
1325 }
1326 return 0;
1327
1328 err_out:
1329 normalize_buffer(STp->buffer);
1330 spin_lock(&st_use_lock);
1331 STp->in_use = 0;
1332 spin_unlock(&st_use_lock);
1333 if (resumed)
1334 scsi_autopm_put_device(STp->device);
1335 scsi_tape_put(STp);
1336 return retval;
1337
1338}
1339
1340
1341/* Flush the tape buffer before close */
1342static int st_flush(struct file *filp, fl_owner_t id)
1343{
1344 int result = 0, result2;
1345 unsigned char cmd[MAX_COMMAND_SIZE];
1346 struct st_request *SRpnt;
1347 struct scsi_tape *STp = filp->private_data;
1348 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1349 struct st_partstat *STps = &(STp->ps[STp->partition]);
1350
1351 if (file_count(filp) > 1)
1352 return 0;
1353
1354 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1355 result = st_flush_write_buffer(STp);
1356 if (result != 0 && result != (-ENOSPC))
1357 goto out;
1358 }
1359
1360 if (STp->can_partitions &&
1361 (result2 = switch_partition(STp)) < 0) {
1362 DEBC_printk(STp, "switch_partition at close failed.\n");
1363 if (result == 0)
1364 result = result2;
1365 goto out;
1366 }
1367
1368 DEBC( if (STp->nbr_requests)
1369 st_printk(KERN_DEBUG, STp,
1370 "Number of r/w requests %d, dio used in %d, "
1371 "pages %d.\n", STp->nbr_requests, STp->nbr_dio,
1372 STp->nbr_pages));
1373
1374 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1375 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1376
1377#if DEBUG
1378 DEBC_printk(STp, "Async write waits %d, finished %d.\n",
1379 STp->nbr_waits, STp->nbr_finished);
1380#endif
1381 memset(cmd, 0, MAX_COMMAND_SIZE);
1382 cmd[0] = WRITE_FILEMARKS;
1383 if (STp->immediate_filemark)
1384 cmd[1] = 1;
1385 cmd[4] = 1 + STp->two_fm;
1386
1387 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1388 STp->device->request_queue->rq_timeout,
1389 MAX_WRITE_RETRIES, 1);
1390 if (!SRpnt) {
1391 result = (STp->buffer)->syscall_result;
1392 goto out;
1393 }
1394
1395 if (STp->buffer->syscall_result == 0 ||
1396 (cmdstatp->have_sense && !cmdstatp->deferred &&
1397 (cmdstatp->flags & SENSE_EOM) &&
1398 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1399 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1400 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1401 /* Write successful at EOM */
1402 st_release_request(SRpnt);
1403 SRpnt = NULL;
1404 if (STps->drv_file >= 0)
1405 STps->drv_file++;
1406 STps->drv_block = 0;
1407 if (STp->two_fm)
1408 cross_eof(STp, 0);
1409 STps->eof = ST_FM;
1410 }
1411 else { /* Write error */
1412 st_release_request(SRpnt);
1413 SRpnt = NULL;
1414 st_printk(KERN_ERR, STp,
1415 "Error on write filemark.\n");
1416 if (result == 0)
1417 result = (-EIO);
1418 }
1419
1420 DEBC_printk(STp, "Buffer flushed, %d EOF(s) written\n", cmd[4]);
1421 } else if (!STp->rew_at_close) {
1422 STps = &(STp->ps[STp->partition]);
1423 if (!STm->sysv || STps->rw != ST_READING) {
1424 if (STp->can_bsr)
1425 result = flush_buffer(STp, 0);
1426 else if (STps->eof == ST_FM_HIT) {
1427 result = cross_eof(STp, 0);
1428 if (result) {
1429 if (STps->drv_file >= 0)
1430 STps->drv_file++;
1431 STps->drv_block = 0;
1432 STps->eof = ST_FM;
1433 } else
1434 STps->eof = ST_NOEOF;
1435 }
1436 } else if ((STps->eof == ST_NOEOF &&
1437 !(result = cross_eof(STp, 1))) ||
1438 STps->eof == ST_FM_HIT) {
1439 if (STps->drv_file >= 0)
1440 STps->drv_file++;
1441 STps->drv_block = 0;
1442 STps->eof = ST_FM;
1443 }
1444 }
1445
1446 out:
1447 if (STp->rew_at_close) {
1448 result2 = st_int_ioctl(STp, MTREW, 1);
1449 if (result == 0)
1450 result = result2;
1451 }
1452 return result;
1453}
1454
1455
1456/* Close the device and release it. BKL is not needed: this is the only thread
1457 accessing this tape. */
1458static int st_release(struct inode *inode, struct file *filp)
1459{
1460 struct scsi_tape *STp = filp->private_data;
1461
1462 if (STp->door_locked == ST_LOCKED_AUTO)
1463 do_door_lock(STp, 0);
1464
1465 normalize_buffer(STp->buffer);
1466 spin_lock(&st_use_lock);
1467 STp->in_use = 0;
1468 spin_unlock(&st_use_lock);
1469 scsi_autopm_put_device(STp->device);
1470 scsi_tape_put(STp);
1471
1472 return 0;
1473}
1474
1475/* The checks common to both reading and writing */
1476static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1477{
1478 ssize_t retval = 0;
1479
1480 /*
1481 * If we are in the middle of error recovery, don't let anyone
1482 * else try and use this device. Also, if error recovery fails, it
1483 * may try and take the device offline, in which case all further
1484 * access to the device is prohibited.
1485 */
1486 if (!scsi_block_when_processing_errors(STp->device)) {
1487 retval = (-ENXIO);
1488 goto out;
1489 }
1490
1491 if (STp->ready != ST_READY) {
1492 if (STp->ready == ST_NO_TAPE)
1493 retval = (-ENOMEDIUM);
1494 else
1495 retval = (-EIO);
1496 goto out;
1497 }
1498
1499 if (! STp->modes[STp->current_mode].defined) {
1500 retval = (-ENXIO);
1501 goto out;
1502 }
1503
1504
1505 /*
1506 * If there was a bus reset, block further access
1507 * to this device.
1508 */
1509 if (STp->pos_unknown) {
1510 retval = (-EIO);
1511 goto out;
1512 }
1513
1514 if (count == 0)
1515 goto out;
1516
1517 DEB(
1518 if (!STp->in_use) {
1519 st_printk(ST_DEB_MSG, STp,
1520 "Incorrect device.\n");
1521 retval = (-EIO);
1522 goto out;
1523 } ) /* end DEB */
1524
1525 if (STp->can_partitions &&
1526 (retval = switch_partition(STp)) < 0)
1527 goto out;
1528
1529 if (STp->block_size == 0 && STp->max_block > 0 &&
1530 (count < STp->min_block || count > STp->max_block)) {
1531 retval = (-EINVAL);
1532 goto out;
1533 }
1534
1535 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1536 !do_door_lock(STp, 1))
1537 STp->door_locked = ST_LOCKED_AUTO;
1538
1539 out:
1540 return retval;
1541}
1542
1543
1544static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1545 size_t count, int is_read)
1546{
1547 int i, bufsize, retval = 0;
1548 struct st_buffer *STbp = STp->buffer;
1549
1550 if (is_read)
1551 i = STp->try_dio_now && try_rdio;
1552 else
1553 i = STp->try_dio_now && try_wdio;
1554
1555 if (i && ((unsigned long)buf & queue_dma_alignment(
1556 STp->device->request_queue)) == 0) {
1557 i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
1558 count, (is_read ? READ : WRITE));
1559 if (i > 0) {
1560 STbp->do_dio = i;
1561 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1562 }
1563 else
1564 STbp->do_dio = 0; /* fall back to buffering with any error */
1565 STbp->sg_segs = STbp->do_dio;
1566 DEB(
1567 if (STbp->do_dio) {
1568 STp->nbr_dio++;
1569 STp->nbr_pages += STbp->do_dio;
1570 }
1571 )
1572 } else
1573 STbp->do_dio = 0;
1574 DEB( STp->nbr_requests++; )
1575
1576 if (!STbp->do_dio) {
1577 if (STp->block_size)
1578 bufsize = STp->block_size > st_fixed_buffer_size ?
1579 STp->block_size : st_fixed_buffer_size;
1580 else {
1581 bufsize = count;
1582 /* Make sure that data from previous user is not leaked even if
1583 HBA does not return correct residual */
1584 if (is_read && STp->sili && !STbp->cleared)
1585 clear_buffer(STbp);
1586 }
1587
1588 if (bufsize > STbp->buffer_size &&
1589 !enlarge_buffer(STbp, bufsize)) {
1590 st_printk(KERN_WARNING, STp,
1591 "Can't allocate %d byte tape buffer.\n",
1592 bufsize);
1593 retval = (-EOVERFLOW);
1594 goto out;
1595 }
1596 if (STp->block_size)
1597 STbp->buffer_blocks = bufsize / STp->block_size;
1598 }
1599
1600 out:
1601 return retval;
1602}
1603
1604
1605/* Can be called more than once after each setup_buffer() */
1606static void release_buffering(struct scsi_tape *STp, int is_read)
1607{
1608 struct st_buffer *STbp;
1609
1610 STbp = STp->buffer;
1611 if (STbp->do_dio) {
1612 sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
1613 STbp->do_dio = 0;
1614 STbp->sg_segs = 0;
1615 }
1616}
1617
1618
1619/* Write command */
1620static ssize_t
1621st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1622{
1623 ssize_t total;
1624 ssize_t i, do_count, blks, transfer;
1625 ssize_t retval;
1626 int undone, retry_eot = 0, scode;
1627 int async_write;
1628 unsigned char cmd[MAX_COMMAND_SIZE];
1629 const char __user *b_point;
1630 struct st_request *SRpnt = NULL;
1631 struct scsi_tape *STp = filp->private_data;
1632 struct st_modedef *STm;
1633 struct st_partstat *STps;
1634 struct st_buffer *STbp;
1635
1636 if (mutex_lock_interruptible(&STp->lock))
1637 return -ERESTARTSYS;
1638
1639 retval = rw_checks(STp, filp, count);
1640 if (retval || count == 0)
1641 goto out;
1642
1643 /* Write must be integral number of blocks */
1644 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1645 st_printk(KERN_WARNING, STp,
1646 "Write not multiple of tape block size.\n");
1647 retval = (-EINVAL);
1648 goto out;
1649 }
1650
1651 STm = &(STp->modes[STp->current_mode]);
1652 STps = &(STp->ps[STp->partition]);
1653
1654 if (STp->write_prot) {
1655 retval = (-EACCES);
1656 goto out;
1657 }
1658
1659
1660 if (STps->rw == ST_READING) {
1661 retval = flush_buffer(STp, 0);
1662 if (retval)
1663 goto out;
1664 STps->rw = ST_WRITING;
1665 } else if (STps->rw != ST_WRITING &&
1666 STps->drv_file == 0 && STps->drv_block == 0) {
1667 if ((retval = set_mode_densblk(STp, STm)) < 0)
1668 goto out;
1669 if (STm->default_compression != ST_DONT_TOUCH &&
1670 !(STp->compression_changed)) {
1671 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1672 st_printk(KERN_WARNING, STp,
1673 "Can't set default compression.\n");
1674 if (modes_defined) {
1675 retval = (-EINVAL);
1676 goto out;
1677 }
1678 }
1679 }
1680 }
1681
1682 STbp = STp->buffer;
1683 i = write_behind_check(STp);
1684 if (i) {
1685 if (i == -ENOSPC)
1686 STps->eof = ST_EOM_OK;
1687 else
1688 STps->eof = ST_EOM_ERROR;
1689 }
1690
1691 if (STps->eof == ST_EOM_OK) {
1692 STps->eof = ST_EOD_1; /* allow next write */
1693 retval = (-ENOSPC);
1694 goto out;
1695 }
1696 else if (STps->eof == ST_EOM_ERROR) {
1697 retval = (-EIO);
1698 goto out;
1699 }
1700
1701 /* Check the buffer readability in cases where copy_user might catch
1702 the problems after some tape movement. */
1703 if (STp->block_size != 0 &&
1704 !STbp->do_dio &&
1705 (copy_from_user(&i, buf, 1) != 0 ||
1706 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1707 retval = (-EFAULT);
1708 goto out;
1709 }
1710
1711 retval = setup_buffering(STp, buf, count, 0);
1712 if (retval)
1713 goto out;
1714
1715 total = count;
1716
1717 memset(cmd, 0, MAX_COMMAND_SIZE);
1718 cmd[0] = WRITE_6;
1719 cmd[1] = (STp->block_size != 0);
1720
1721 STps->rw = ST_WRITING;
1722
1723 b_point = buf;
1724 while (count > 0 && !retry_eot) {
1725
1726 if (STbp->do_dio) {
1727 do_count = count;
1728 }
1729 else {
1730 if (STp->block_size == 0)
1731 do_count = count;
1732 else {
1733 do_count = STbp->buffer_blocks * STp->block_size -
1734 STbp->buffer_bytes;
1735 if (do_count > count)
1736 do_count = count;
1737 }
1738
1739 i = append_to_buffer(b_point, STbp, do_count);
1740 if (i) {
1741 retval = i;
1742 goto out;
1743 }
1744 }
1745 count -= do_count;
1746 b_point += do_count;
1747
1748 async_write = STp->block_size == 0 && !STbp->do_dio &&
1749 STm->do_async_writes && STps->eof < ST_EOM_OK;
1750
1751 if (STp->block_size != 0 && STm->do_buffer_writes &&
1752 !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
1753 STbp->buffer_bytes < STbp->buffer_size) {
1754 STp->dirty = 1;
1755 /* Don't write a buffer that is not full enough. */
1756 if (!async_write && count == 0)
1757 break;
1758 }
1759
1760 retry_write:
1761 if (STp->block_size == 0)
1762 blks = transfer = do_count;
1763 else {
1764 if (!STbp->do_dio)
1765 blks = STbp->buffer_bytes;
1766 else
1767 blks = do_count;
1768 blks /= STp->block_size;
1769 transfer = blks * STp->block_size;
1770 }
1771 cmd[2] = blks >> 16;
1772 cmd[3] = blks >> 8;
1773 cmd[4] = blks;
1774
1775 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1776 STp->device->request_queue->rq_timeout,
1777 MAX_WRITE_RETRIES, !async_write);
1778 if (!SRpnt) {
1779 retval = STbp->syscall_result;
1780 goto out;
1781 }
1782 if (async_write && !STbp->syscall_result) {
1783 STbp->writing = transfer;
1784 STp->dirty = !(STbp->writing ==
1785 STbp->buffer_bytes);
1786 SRpnt = NULL; /* Prevent releasing this request! */
1787 DEB( STp->write_pending = 1; )
1788 break;
1789 }
1790
1791 if (STbp->syscall_result != 0) {
1792 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1793
1794 DEBC_printk(STp, "Error on write:\n");
1795 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1796 scode = cmdstatp->sense_hdr.sense_key;
1797 if (cmdstatp->remainder_valid)
1798 undone = (int)cmdstatp->uremainder64;
1799 else if (STp->block_size == 0 &&
1800 scode == VOLUME_OVERFLOW)
1801 undone = transfer;
1802 else
1803 undone = 0;
1804 if (STp->block_size != 0)
1805 undone *= STp->block_size;
1806 if (undone <= do_count) {
1807 /* Only data from this write is not written */
1808 count += undone;
1809 b_point -= undone;
1810 do_count -= undone;
1811 if (STp->block_size)
1812 blks = (transfer - undone) / STp->block_size;
1813 STps->eof = ST_EOM_OK;
1814 /* Continue in fixed block mode if all written
1815 in this request but still something left to write
1816 (retval left to zero)
1817 */
1818 if (STp->block_size == 0 ||
1819 undone > 0 || count == 0)
1820 retval = (-ENOSPC); /* EOM within current request */
1821 DEBC_printk(STp, "EOM with %d "
1822 "bytes unwritten.\n",
1823 (int)count);
1824 } else {
1825 /* EOT within data buffered earlier (possible only
1826 in fixed block mode without direct i/o) */
1827 if (!retry_eot && !cmdstatp->deferred &&
1828 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1829 move_buffer_data(STp->buffer, transfer - undone);
1830 retry_eot = 1;
1831 if (STps->drv_block >= 0) {
1832 STps->drv_block += (transfer - undone) /
1833 STp->block_size;
1834 }
1835 STps->eof = ST_EOM_OK;
1836 DEBC_printk(STp, "Retry "
1837 "write of %d "
1838 "bytes at EOM.\n",
1839 STp->buffer->buffer_bytes);
1840 goto retry_write;
1841 }
1842 else {
1843 /* Either error within data buffered by driver or
1844 failed retry */
1845 count -= do_count;
1846 blks = do_count = 0;
1847 STps->eof = ST_EOM_ERROR;
1848 STps->drv_block = (-1); /* Too cautious? */
1849 retval = (-EIO); /* EOM for old data */
1850 DEBC_printk(STp, "EOM with "
1851 "lost data.\n");
1852 }
1853 }
1854 } else {
1855 count += do_count;
1856 STps->drv_block = (-1); /* Too cautious? */
1857 retval = STbp->syscall_result;
1858 }
1859
1860 }
1861
1862 if (STps->drv_block >= 0) {
1863 if (STp->block_size == 0)
1864 STps->drv_block += (do_count > 0);
1865 else
1866 STps->drv_block += blks;
1867 }
1868
1869 STbp->buffer_bytes = 0;
1870 STp->dirty = 0;
1871
1872 if (retval || retry_eot) {
1873 if (count < total)
1874 retval = total - count;
1875 goto out;
1876 }
1877 }
1878
1879 if (STps->eof == ST_EOD_1)
1880 STps->eof = ST_EOM_OK;
1881 else if (STps->eof != ST_EOM_OK)
1882 STps->eof = ST_NOEOF;
1883 retval = total - count;
1884
1885 out:
1886 if (SRpnt != NULL)
1887 st_release_request(SRpnt);
1888 release_buffering(STp, 0);
1889 mutex_unlock(&STp->lock);
1890
1891 return retval;
1892}
1893
1894/* Read data from the tape. Returns zero in the normal case, one if the
1895 eof status has changed, and the negative error code in case of a
1896 fatal error. Otherwise updates the buffer and the eof state.
1897
1898 Does release user buffer mapping if it is set.
1899*/
1900static long read_tape(struct scsi_tape *STp, long count,
1901 struct st_request ** aSRpnt)
1902{
1903 int transfer, blks, bytes;
1904 unsigned char cmd[MAX_COMMAND_SIZE];
1905 struct st_request *SRpnt;
1906 struct st_modedef *STm;
1907 struct st_partstat *STps;
1908 struct st_buffer *STbp;
1909 int retval = 0;
1910
1911 if (count == 0)
1912 return 0;
1913
1914 STm = &(STp->modes[STp->current_mode]);
1915 STps = &(STp->ps[STp->partition]);
1916 if (STps->eof == ST_FM_HIT)
1917 return 1;
1918 STbp = STp->buffer;
1919
1920 if (STp->block_size == 0)
1921 blks = bytes = count;
1922 else {
1923 if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
1924 blks = (STp->buffer)->buffer_blocks;
1925 bytes = blks * STp->block_size;
1926 } else {
1927 bytes = count;
1928 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1929 bytes = (STp->buffer)->buffer_size;
1930 blks = bytes / STp->block_size;
1931 bytes = blks * STp->block_size;
1932 }
1933 }
1934
1935 memset(cmd, 0, MAX_COMMAND_SIZE);
1936 cmd[0] = READ_6;
1937 cmd[1] = (STp->block_size != 0);
1938 if (!cmd[1] && STp->sili)
1939 cmd[1] |= 2;
1940 cmd[2] = blks >> 16;
1941 cmd[3] = blks >> 8;
1942 cmd[4] = blks;
1943
1944 SRpnt = *aSRpnt;
1945 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1946 STp->device->request_queue->rq_timeout,
1947 MAX_RETRIES, 1);
1948 release_buffering(STp, 1);
1949 *aSRpnt = SRpnt;
1950 if (!SRpnt)
1951 return STbp->syscall_result;
1952
1953 STbp->read_pointer = 0;
1954 STps->at_sm = 0;
1955
1956 /* Something to check */
1957 if (STbp->syscall_result) {
1958 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1959
1960 retval = 1;
1961 DEBC_printk(STp,
1962 "Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1963 SRpnt->sense[0], SRpnt->sense[1],
1964 SRpnt->sense[2], SRpnt->sense[3],
1965 SRpnt->sense[4], SRpnt->sense[5],
1966 SRpnt->sense[6], SRpnt->sense[7]);
1967 if (cmdstatp->have_sense) {
1968
1969 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1970 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1971
1972 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1973 /* Compute the residual count */
1974 if (cmdstatp->remainder_valid)
1975 transfer = (int)cmdstatp->uremainder64;
1976 else
1977 transfer = 0;
1978 if (cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR) {
1979 if (STp->block_size == 0)
1980 transfer = bytes;
1981 /* Some drives set ILI with MEDIUM ERROR */
1982 cmdstatp->flags &= ~SENSE_ILI;
1983 }
1984
1985 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1986 if (STp->block_size == 0 &&
1987 transfer < 0) {
1988 st_printk(KERN_NOTICE, STp,
1989 "Failed to read %d "
1990 "byte block with %d "
1991 "byte transfer.\n",
1992 bytes - transfer,
1993 bytes);
1994 if (STps->drv_block >= 0)
1995 STps->drv_block += 1;
1996 STbp->buffer_bytes = 0;
1997 return (-ENOMEM);
1998 } else if (STp->block_size == 0) {
1999 STbp->buffer_bytes = bytes - transfer;
2000 } else {
2001 st_release_request(SRpnt);
2002 SRpnt = *aSRpnt = NULL;
2003 if (transfer == blks) { /* We did not get anything, error */
2004 st_printk(KERN_NOTICE, STp,
2005 "Incorrect "
2006 "block size.\n");
2007 if (STps->drv_block >= 0)
2008 STps->drv_block += blks - transfer + 1;
2009 st_int_ioctl(STp, MTBSR, 1);
2010 return (-EIO);
2011 }
2012 /* We have some data, deliver it */
2013 STbp->buffer_bytes = (blks - transfer) *
2014 STp->block_size;
2015 DEBC_printk(STp, "ILI but "
2016 "enough data "
2017 "received %ld "
2018 "%d.\n", count,
2019 STbp->buffer_bytes);
2020 if (STps->drv_block >= 0)
2021 STps->drv_block += 1;
2022 if (st_int_ioctl(STp, MTBSR, 1))
2023 return (-EIO);
2024 }
2025 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
2026 if (STps->eof != ST_FM_HIT)
2027 STps->eof = ST_FM_HIT;
2028 else
2029 STps->eof = ST_EOD_2;
2030 if (STp->block_size == 0)
2031 STbp->buffer_bytes = 0;
2032 else
2033 STbp->buffer_bytes =
2034 bytes - transfer * STp->block_size;
2035 DEBC_printk(STp, "EOF detected (%d "
2036 "bytes read).\n",
2037 STbp->buffer_bytes);
2038 } else if (cmdstatp->flags & SENSE_EOM) {
2039 if (STps->eof == ST_FM)
2040 STps->eof = ST_EOD_1;
2041 else
2042 STps->eof = ST_EOM_OK;
2043 if (STp->block_size == 0)
2044 STbp->buffer_bytes = bytes - transfer;
2045 else
2046 STbp->buffer_bytes =
2047 bytes - transfer * STp->block_size;
2048
2049 DEBC_printk(STp, "EOM detected (%d "
2050 "bytes read).\n",
2051 STbp->buffer_bytes);
2052 }
2053 }
2054 /* end of EOF, EOM, ILI test */
2055 else { /* nonzero sense key */
2056 DEBC_printk(STp, "Tape error while reading.\n");
2057 STps->drv_block = (-1);
2058 if (STps->eof == ST_FM &&
2059 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
2060 DEBC_printk(STp, "Zero returned for "
2061 "first BLANK CHECK "
2062 "after EOF.\n");
2063 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
2064 } else /* Some other extended sense code */
2065 retval = (-EIO);
2066 }
2067
2068 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
2069 STbp->buffer_bytes = 0;
2070 }
2071 /* End of extended sense test */
2072 else { /* Non-extended sense */
2073 retval = STbp->syscall_result;
2074 }
2075
2076 }
2077 /* End of error handling */
2078 else { /* Read successful */
2079 STbp->buffer_bytes = bytes;
2080 if (STp->sili) /* In fixed block mode residual is always zero here */
2081 STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
2082 }
2083
2084 if (STps->drv_block >= 0) {
2085 if (STp->block_size == 0)
2086 STps->drv_block++;
2087 else
2088 STps->drv_block += STbp->buffer_bytes / STp->block_size;
2089 }
2090 return retval;
2091}
2092
2093
2094/* Read command */
2095static ssize_t
2096st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
2097{
2098 ssize_t total;
2099 ssize_t retval = 0;
2100 ssize_t i, transfer;
2101 int special, do_dio = 0;
2102 struct st_request *SRpnt = NULL;
2103 struct scsi_tape *STp = filp->private_data;
2104 struct st_modedef *STm;
2105 struct st_partstat *STps;
2106 struct st_buffer *STbp = STp->buffer;
2107
2108 if (mutex_lock_interruptible(&STp->lock))
2109 return -ERESTARTSYS;
2110
2111 retval = rw_checks(STp, filp, count);
2112 if (retval || count == 0)
2113 goto out;
2114
2115 STm = &(STp->modes[STp->current_mode]);
2116 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
2117 if (!STm->do_read_ahead) {
2118 retval = (-EINVAL); /* Read must be integral number of blocks */
2119 goto out;
2120 }
2121 STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
2122 }
2123
2124 STps = &(STp->ps[STp->partition]);
2125 if (STps->rw == ST_WRITING) {
2126 retval = flush_buffer(STp, 0);
2127 if (retval)
2128 goto out;
2129 STps->rw = ST_READING;
2130 }
2131 DEB(
2132 if (debugging && STps->eof != ST_NOEOF)
2133 st_printk(ST_DEB_MSG, STp,
2134 "EOF/EOM flag up (%d). Bytes %d\n",
2135 STps->eof, STbp->buffer_bytes);
2136 ) /* end DEB */
2137
2138 retval = setup_buffering(STp, buf, count, 1);
2139 if (retval)
2140 goto out;
2141 do_dio = STbp->do_dio;
2142
2143 if (STbp->buffer_bytes == 0 &&
2144 STps->eof >= ST_EOD_1) {
2145 if (STps->eof < ST_EOD) {
2146 STps->eof += 1;
2147 retval = 0;
2148 goto out;
2149 }
2150 retval = (-EIO); /* EOM or Blank Check */
2151 goto out;
2152 }
2153
2154 if (do_dio) {
2155 /* Check the buffer writability before any tape movement. Don't alter
2156 buffer data. */
2157 if (copy_from_user(&i, buf, 1) != 0 ||
2158 copy_to_user(buf, &i, 1) != 0 ||
2159 copy_from_user(&i, buf + count - 1, 1) != 0 ||
2160 copy_to_user(buf + count - 1, &i, 1) != 0) {
2161 retval = (-EFAULT);
2162 goto out;
2163 }
2164 }
2165
2166 STps->rw = ST_READING;
2167
2168
2169 /* Loop until enough data in buffer or a special condition found */
2170 for (total = 0, special = 0; total < count && !special;) {
2171
2172 /* Get new data if the buffer is empty */
2173 if (STbp->buffer_bytes == 0) {
2174 special = read_tape(STp, count - total, &SRpnt);
2175 if (special < 0) { /* No need to continue read */
2176 retval = special;
2177 goto out;
2178 }
2179 }
2180
2181 /* Move the data from driver buffer to user buffer */
2182 if (STbp->buffer_bytes > 0) {
2183 DEB(
2184 if (debugging && STps->eof != ST_NOEOF)
2185 st_printk(ST_DEB_MSG, STp,
2186 "EOF up (%d). Left %d, needed %d.\n",
2187 STps->eof, STbp->buffer_bytes,
2188 (int)(count - total));
2189 ) /* end DEB */
2190 transfer = STbp->buffer_bytes < count - total ?
2191 STbp->buffer_bytes : count - total;
2192 if (!do_dio) {
2193 i = from_buffer(STbp, buf, transfer);
2194 if (i) {
2195 retval = i;
2196 goto out;
2197 }
2198 }
2199 buf += transfer;
2200 total += transfer;
2201 }
2202
2203 if (STp->block_size == 0)
2204 break; /* Read only one variable length block */
2205
2206 } /* for (total = 0, special = 0;
2207 total < count && !special; ) */
2208
2209 /* Change the eof state if no data from tape or buffer */
2210 if (total == 0) {
2211 if (STps->eof == ST_FM_HIT) {
2212 STps->eof = ST_FM;
2213 STps->drv_block = 0;
2214 if (STps->drv_file >= 0)
2215 STps->drv_file++;
2216 } else if (STps->eof == ST_EOD_1) {
2217 STps->eof = ST_EOD_2;
2218 STps->drv_block = 0;
2219 if (STps->drv_file >= 0)
2220 STps->drv_file++;
2221 } else if (STps->eof == ST_EOD_2)
2222 STps->eof = ST_EOD;
2223 } else if (STps->eof == ST_FM)
2224 STps->eof = ST_NOEOF;
2225 retval = total;
2226
2227 out:
2228 if (SRpnt != NULL) {
2229 st_release_request(SRpnt);
2230 SRpnt = NULL;
2231 }
2232 if (do_dio) {
2233 release_buffering(STp, 1);
2234 STbp->buffer_bytes = 0;
2235 }
2236 mutex_unlock(&STp->lock);
2237
2238 return retval;
2239}
2240
2241
2242
2243DEB(
2244/* Set the driver options */
2245static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm)
2246{
2247 if (debugging) {
2248 st_printk(KERN_INFO, STp,
2249 "Mode %d options: buffer writes: %d, "
2250 "async writes: %d, read ahead: %d\n",
2251 STp->current_mode, STm->do_buffer_writes,
2252 STm->do_async_writes, STm->do_read_ahead);
2253 st_printk(KERN_INFO, STp,
2254 " can bsr: %d, two FMs: %d, "
2255 "fast mteom: %d, auto lock: %d,\n",
2256 STp->can_bsr, STp->two_fm, STp->fast_mteom,
2257 STp->do_auto_lock);
2258 st_printk(KERN_INFO, STp,
2259 " defs for wr: %d, no block limits: %d, "
2260 "partitions: %d, s2 log: %d\n",
2261 STm->defaults_for_writes, STp->omit_blklims,
2262 STp->can_partitions, STp->scsi2_logical);
2263 st_printk(KERN_INFO, STp,
2264 " sysv: %d nowait: %d sili: %d "
2265 "nowait_filemark: %d\n",
2266 STm->sysv, STp->immediate, STp->sili,
2267 STp->immediate_filemark);
2268 st_printk(KERN_INFO, STp, " debugging: %d\n", debugging);
2269 }
2270}
2271 )
2272
2273
2274static int st_set_options(struct scsi_tape *STp, long options)
2275{
2276 int value;
2277 long code;
2278 struct st_modedef *STm;
2279 struct cdev *cd0, *cd1;
2280 struct device *d0, *d1;
2281
2282 STm = &(STp->modes[STp->current_mode]);
2283 if (!STm->defined) {
2284 cd0 = STm->cdevs[0];
2285 cd1 = STm->cdevs[1];
2286 d0 = STm->devs[0];
2287 d1 = STm->devs[1];
2288 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2289 STm->cdevs[0] = cd0;
2290 STm->cdevs[1] = cd1;
2291 STm->devs[0] = d0;
2292 STm->devs[1] = d1;
2293 modes_defined = 1;
2294 DEBC_printk(STp, "Initialized mode %d definition from mode 0\n",
2295 STp->current_mode);
2296 }
2297
2298 code = options & MT_ST_OPTIONS;
2299 if (code == MT_ST_BOOLEANS) {
2300 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2301 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2302 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2303 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2304 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2305 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2306 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2307 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2308 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2309 if ((STp->device)->scsi_level >= SCSI_2)
2310 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2311 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2312 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2313 STp->immediate_filemark = (options & MT_ST_NOWAIT_EOF) != 0;
2314 STm->sysv = (options & MT_ST_SYSV) != 0;
2315 STp->sili = (options & MT_ST_SILI) != 0;
2316 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2317 st_log_options(STp, STm); )
2318 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2319 value = (code == MT_ST_SETBOOLEANS);
2320 if ((options & MT_ST_BUFFER_WRITES) != 0)
2321 STm->do_buffer_writes = value;
2322 if ((options & MT_ST_ASYNC_WRITES) != 0)
2323 STm->do_async_writes = value;
2324 if ((options & MT_ST_DEF_WRITES) != 0)
2325 STm->defaults_for_writes = value;
2326 if ((options & MT_ST_READ_AHEAD) != 0)
2327 STm->do_read_ahead = value;
2328 if ((options & MT_ST_TWO_FM) != 0)
2329 STp->two_fm = value;
2330 if ((options & MT_ST_FAST_MTEOM) != 0)
2331 STp->fast_mteom = value;
2332 if ((options & MT_ST_AUTO_LOCK) != 0)
2333 STp->do_auto_lock = value;
2334 if ((options & MT_ST_CAN_BSR) != 0)
2335 STp->can_bsr = value;
2336 if ((options & MT_ST_NO_BLKLIMS) != 0)
2337 STp->omit_blklims = value;
2338 if ((STp->device)->scsi_level >= SCSI_2 &&
2339 (options & MT_ST_CAN_PARTITIONS) != 0)
2340 STp->can_partitions = value;
2341 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2342 STp->scsi2_logical = value;
2343 if ((options & MT_ST_NOWAIT) != 0)
2344 STp->immediate = value;
2345 if ((options & MT_ST_NOWAIT_EOF) != 0)
2346 STp->immediate_filemark = value;
2347 if ((options & MT_ST_SYSV) != 0)
2348 STm->sysv = value;
2349 if ((options & MT_ST_SILI) != 0)
2350 STp->sili = value;
2351 DEB(
2352 if ((options & MT_ST_DEBUGGING) != 0)
2353 debugging = value;
2354 st_log_options(STp, STm); )
2355 } else if (code == MT_ST_WRITE_THRESHOLD) {
2356 /* Retained for compatibility */
2357 } else if (code == MT_ST_DEF_BLKSIZE) {
2358 value = (options & ~MT_ST_OPTIONS);
2359 if (value == ~MT_ST_OPTIONS) {
2360 STm->default_blksize = (-1);
2361 DEBC_printk(STp, "Default block size disabled.\n");
2362 } else {
2363 STm->default_blksize = value;
2364 DEBC_printk(STp,"Default block size set to "
2365 "%d bytes.\n", STm->default_blksize);
2366 if (STp->ready == ST_READY) {
2367 STp->blksize_changed = 0;
2368 set_mode_densblk(STp, STm);
2369 }
2370 }
2371 } else if (code == MT_ST_TIMEOUTS) {
2372 value = (options & ~MT_ST_OPTIONS);
2373 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2374 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2375 DEBC_printk(STp, "Long timeout set to %d seconds.\n",
2376 (value & ~MT_ST_SET_LONG_TIMEOUT));
2377 } else {
2378 blk_queue_rq_timeout(STp->device->request_queue,
2379 value * HZ);
2380 DEBC_printk(STp, "Normal timeout set to %d seconds.\n",
2381 value);
2382 }
2383 } else if (code == MT_ST_SET_CLN) {
2384 value = (options & ~MT_ST_OPTIONS) & 0xff;
2385 if (value != 0 &&
2386 (value < EXTENDED_SENSE_START ||
2387 value >= SCSI_SENSE_BUFFERSIZE))
2388 return (-EINVAL);
2389 STp->cln_mode = value;
2390 STp->cln_sense_mask = (options >> 8) & 0xff;
2391 STp->cln_sense_value = (options >> 16) & 0xff;
2392 st_printk(KERN_INFO, STp,
2393 "Cleaning request mode %d, mask %02x, value %02x\n",
2394 value, STp->cln_sense_mask, STp->cln_sense_value);
2395 } else if (code == MT_ST_DEF_OPTIONS) {
2396 code = (options & ~MT_ST_CLEAR_DEFAULT);
2397 value = (options & MT_ST_CLEAR_DEFAULT);
2398 if (code == MT_ST_DEF_DENSITY) {
2399 if (value == MT_ST_CLEAR_DEFAULT) {
2400 STm->default_density = (-1);
2401 DEBC_printk(STp,
2402 "Density default disabled.\n");
2403 } else {
2404 STm->default_density = value & 0xff;
2405 DEBC_printk(STp, "Density default set to %x\n",
2406 STm->default_density);
2407 if (STp->ready == ST_READY) {
2408 STp->density_changed = 0;
2409 set_mode_densblk(STp, STm);
2410 }
2411 }
2412 } else if (code == MT_ST_DEF_DRVBUFFER) {
2413 if (value == MT_ST_CLEAR_DEFAULT) {
2414 STp->default_drvbuffer = 0xff;
2415 DEBC_printk(STp,
2416 "Drive buffer default disabled.\n");
2417 } else {
2418 STp->default_drvbuffer = value & 7;
2419 DEBC_printk(STp,
2420 "Drive buffer default set to %x\n",
2421 STp->default_drvbuffer);
2422 if (STp->ready == ST_READY)
2423 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2424 }
2425 } else if (code == MT_ST_DEF_COMPRESSION) {
2426 if (value == MT_ST_CLEAR_DEFAULT) {
2427 STm->default_compression = ST_DONT_TOUCH;
2428 DEBC_printk(STp,
2429 "Compression default disabled.\n");
2430 } else {
2431 if ((value & 0xff00) != 0) {
2432 STp->c_algo = (value & 0xff00) >> 8;
2433 DEBC_printk(STp, "Compression "
2434 "algorithm set to 0x%x.\n",
2435 STp->c_algo);
2436 }
2437 if ((value & 0xff) != 0xff) {
2438 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2439 DEBC_printk(STp, "Compression default "
2440 "set to %x\n",
2441 (value & 1));
2442 if (STp->ready == ST_READY) {
2443 STp->compression_changed = 0;
2444 st_compression(STp, (STm->default_compression == ST_YES));
2445 }
2446 }
2447 }
2448 }
2449 } else
2450 return (-EIO);
2451
2452 return 0;
2453}
2454
2455#define MODE_HEADER_LENGTH 4
2456
2457/* Mode header and page byte offsets */
2458#define MH_OFF_DATA_LENGTH 0
2459#define MH_OFF_MEDIUM_TYPE 1
2460#define MH_OFF_DEV_SPECIFIC 2
2461#define MH_OFF_BDESCS_LENGTH 3
2462#define MP_OFF_PAGE_NBR 0
2463#define MP_OFF_PAGE_LENGTH 1
2464
2465/* Mode header and page bit masks */
2466#define MH_BIT_WP 0x80
2467#define MP_MSK_PAGE_NBR 0x3f
2468
2469/* Don't return block descriptors */
2470#define MODE_SENSE_OMIT_BDESCS 0x08
2471
2472#define MODE_SELECT_PAGE_FORMAT 0x10
2473
2474/* Read a mode page into the tape buffer. The block descriptors are included
2475 if incl_block_descs is true. The page control is ored to the page number
2476 parameter, if necessary. */
2477static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2478{
2479 unsigned char cmd[MAX_COMMAND_SIZE];
2480 struct st_request *SRpnt;
2481
2482 memset(cmd, 0, MAX_COMMAND_SIZE);
2483 cmd[0] = MODE_SENSE;
2484 if (omit_block_descs)
2485 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2486 cmd[2] = page;
2487 cmd[4] = 255;
2488
2489 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2490 STp->device->request_queue->rq_timeout, 0, 1);
2491 if (SRpnt == NULL)
2492 return (STp->buffer)->syscall_result;
2493
2494 st_release_request(SRpnt);
2495
2496 return STp->buffer->syscall_result;
2497}
2498
2499
2500/* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2501 in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
2502static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2503{
2504 int pgo;
2505 unsigned char cmd[MAX_COMMAND_SIZE];
2506 struct st_request *SRpnt;
2507 int timeout;
2508
2509 memset(cmd, 0, MAX_COMMAND_SIZE);
2510 cmd[0] = MODE_SELECT;
2511 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2512 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2513 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2514
2515 /* Clear reserved fields */
2516 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2517 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2518 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2519 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2520
2521 timeout = slow ?
2522 STp->long_timeout : STp->device->request_queue->rq_timeout;
2523 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
2524 timeout, 0, 1);
2525 if (SRpnt == NULL)
2526 return (STp->buffer)->syscall_result;
2527
2528 st_release_request(SRpnt);
2529
2530 return STp->buffer->syscall_result;
2531}
2532
2533
2534#define COMPRESSION_PAGE 0x0f
2535#define COMPRESSION_PAGE_LENGTH 16
2536
2537#define CP_OFF_DCE_DCC 2
2538#define CP_OFF_C_ALGO 7
2539
2540#define DCE_MASK 0x80
2541#define DCC_MASK 0x40
2542#define RED_MASK 0x60
2543
2544
2545/* Control the compression with mode page 15. Algorithm not changed if zero.
2546
2547 The block descriptors are read and written because Sony SDT-7000 does not
2548 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2549 Including block descriptors should not cause any harm to other drives. */
2550
2551static int st_compression(struct scsi_tape * STp, int state)
2552{
2553 int retval;
2554 int mpoffs; /* Offset to mode page start */
2555 unsigned char *b_data = (STp->buffer)->b_data;
2556
2557 if (STp->ready != ST_READY)
2558 return (-EIO);
2559
2560 /* Read the current page contents */
2561 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2562 if (retval) {
2563 DEBC_printk(STp, "Compression mode page not supported.\n");
2564 return (-EIO);
2565 }
2566
2567 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2568 DEBC_printk(STp, "Compression state is %d.\n",
2569 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0));
2570
2571 /* Check if compression can be changed */
2572 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2573 DEBC_printk(STp, "Compression not supported.\n");
2574 return (-EIO);
2575 }
2576
2577 /* Do the change */
2578 if (state) {
2579 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2580 if (STp->c_algo != 0)
2581 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2582 }
2583 else {
2584 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2585 if (STp->c_algo != 0)
2586 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2587 }
2588
2589 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2590 if (retval) {
2591 DEBC_printk(STp, "Compression change failed.\n");
2592 return (-EIO);
2593 }
2594 DEBC_printk(STp, "Compression state changed to %d.\n", state);
2595
2596 STp->compression_changed = 1;
2597 return 0;
2598}
2599
2600
2601/* Process the load and unload commands (does unload if the load code is zero) */
2602static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2603{
2604 int retval = (-EIO), timeout;
2605 unsigned char cmd[MAX_COMMAND_SIZE];
2606 struct st_partstat *STps;
2607 struct st_request *SRpnt;
2608
2609 if (STp->ready != ST_READY && !load_code) {
2610 if (STp->ready == ST_NO_TAPE)
2611 return (-ENOMEDIUM);
2612 else
2613 return (-EIO);
2614 }
2615
2616 memset(cmd, 0, MAX_COMMAND_SIZE);
2617 cmd[0] = START_STOP;
2618 if (load_code)
2619 cmd[4] |= 1;
2620 /*
2621 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2622 */
2623 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2624 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2625 DEBC_printk(STp, " Enhanced %sload slot %2d.\n",
2626 (cmd[4]) ? "" : "un",
2627 load_code - MT_ST_HPLOADER_OFFSET);
2628 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2629 }
2630 if (STp->immediate) {
2631 cmd[1] = 1; /* Don't wait for completion */
2632 timeout = STp->device->request_queue->rq_timeout;
2633 }
2634 else
2635 timeout = STp->long_timeout;
2636
2637 DEBC(
2638 if (!load_code)
2639 st_printk(ST_DEB_MSG, STp, "Unloading tape.\n");
2640 else
2641 st_printk(ST_DEB_MSG, STp, "Loading tape.\n");
2642 );
2643
2644 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2645 timeout, MAX_RETRIES, 1);
2646 if (!SRpnt)
2647 return (STp->buffer)->syscall_result;
2648
2649 retval = (STp->buffer)->syscall_result;
2650 st_release_request(SRpnt);
2651
2652 if (!retval) { /* SCSI command successful */
2653
2654 if (!load_code) {
2655 STp->rew_at_close = 0;
2656 STp->ready = ST_NO_TAPE;
2657 }
2658 else {
2659 STp->rew_at_close = STp->autorew_dev;
2660 retval = check_tape(STp, filp);
2661 if (retval > 0)
2662 retval = 0;
2663 }
2664 }
2665 else {
2666 STps = &(STp->ps[STp->partition]);
2667 STps->drv_file = STps->drv_block = (-1);
2668 }
2669
2670 return retval;
2671}
2672
2673#if DEBUG
2674#define ST_DEB_FORWARD 0
2675#define ST_DEB_BACKWARD 1
2676static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd)
2677{
2678 s32 sc;
2679
2680 if (!debugging)
2681 return;
2682
2683 sc = sign_extend32(get_unaligned_be24(&cmd[2]), 23);
2684 if (direction)
2685 sc = -sc;
2686 st_printk(ST_DEB_MSG, STp, "Spacing tape %s over %d %s.\n",
2687 direction ? "backward" : "forward", sc, units);
2688}
2689#else
2690#define ST_DEB_FORWARD 0
2691#define ST_DEB_BACKWARD 1
2692static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd) {}
2693#endif
2694
2695
2696/* Internal ioctl function */
2697static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2698{
2699 int timeout;
2700 long ltmp;
2701 int ioctl_result;
2702 int chg_eof = 1;
2703 unsigned char cmd[MAX_COMMAND_SIZE];
2704 struct st_request *SRpnt;
2705 struct st_partstat *STps;
2706 int fileno, blkno, at_sm, undone;
2707 int datalen = 0, direction = DMA_NONE;
2708
2709 WARN_ON(STp->buffer->do_dio != 0);
2710 if (STp->ready != ST_READY) {
2711 if (STp->ready == ST_NO_TAPE)
2712 return (-ENOMEDIUM);
2713 else
2714 return (-EIO);
2715 }
2716 timeout = STp->long_timeout;
2717 STps = &(STp->ps[STp->partition]);
2718 fileno = STps->drv_file;
2719 blkno = STps->drv_block;
2720 at_sm = STps->at_sm;
2721
2722 memset(cmd, 0, MAX_COMMAND_SIZE);
2723 switch (cmd_in) {
2724 case MTFSFM:
2725 chg_eof = 0; /* Changed from the FSF after this */
2726 fallthrough;
2727 case MTFSF:
2728 cmd[0] = SPACE;
2729 cmd[1] = 0x01; /* Space FileMarks */
2730 cmd[2] = (arg >> 16);
2731 cmd[3] = (arg >> 8);
2732 cmd[4] = arg;
2733 deb_space_print(STp, ST_DEB_FORWARD, "filemarks", cmd);
2734 if (fileno >= 0)
2735 fileno += arg;
2736 blkno = 0;
2737 at_sm &= (arg == 0);
2738 break;
2739 case MTBSFM:
2740 chg_eof = 0; /* Changed from the FSF after this */
2741 fallthrough;
2742 case MTBSF:
2743 cmd[0] = SPACE;
2744 cmd[1] = 0x01; /* Space FileMarks */
2745 ltmp = (-arg);
2746 cmd[2] = (ltmp >> 16);
2747 cmd[3] = (ltmp >> 8);
2748 cmd[4] = ltmp;
2749 deb_space_print(STp, ST_DEB_BACKWARD, "filemarks", cmd);
2750 if (fileno >= 0)
2751 fileno -= arg;
2752 blkno = (-1); /* We can't know the block number */
2753 at_sm &= (arg == 0);
2754 break;
2755 case MTFSR:
2756 cmd[0] = SPACE;
2757 cmd[1] = 0x00; /* Space Blocks */
2758 cmd[2] = (arg >> 16);
2759 cmd[3] = (arg >> 8);
2760 cmd[4] = arg;
2761 deb_space_print(STp, ST_DEB_FORWARD, "blocks", cmd);
2762 if (blkno >= 0)
2763 blkno += arg;
2764 at_sm &= (arg == 0);
2765 break;
2766 case MTBSR:
2767 cmd[0] = SPACE;
2768 cmd[1] = 0x00; /* Space Blocks */
2769 ltmp = (-arg);
2770 cmd[2] = (ltmp >> 16);
2771 cmd[3] = (ltmp >> 8);
2772 cmd[4] = ltmp;
2773 deb_space_print(STp, ST_DEB_BACKWARD, "blocks", cmd);
2774 if (blkno >= 0)
2775 blkno -= arg;
2776 at_sm &= (arg == 0);
2777 break;
2778 case MTFSS:
2779 cmd[0] = SPACE;
2780 cmd[1] = 0x04; /* Space Setmarks */
2781 cmd[2] = (arg >> 16);
2782 cmd[3] = (arg >> 8);
2783 cmd[4] = arg;
2784 deb_space_print(STp, ST_DEB_FORWARD, "setmarks", cmd);
2785 if (arg != 0) {
2786 blkno = fileno = (-1);
2787 at_sm = 1;
2788 }
2789 break;
2790 case MTBSS:
2791 cmd[0] = SPACE;
2792 cmd[1] = 0x04; /* Space Setmarks */
2793 ltmp = (-arg);
2794 cmd[2] = (ltmp >> 16);
2795 cmd[3] = (ltmp >> 8);
2796 cmd[4] = ltmp;
2797 deb_space_print(STp, ST_DEB_BACKWARD, "setmarks", cmd);
2798 if (arg != 0) {
2799 blkno = fileno = (-1);
2800 at_sm = 1;
2801 }
2802 break;
2803 case MTWEOF:
2804 case MTWEOFI:
2805 case MTWSM:
2806 if (STp->write_prot)
2807 return (-EACCES);
2808 cmd[0] = WRITE_FILEMARKS;
2809 if (cmd_in == MTWSM)
2810 cmd[1] = 2;
2811 if (cmd_in == MTWEOFI ||
2812 (cmd_in == MTWEOF && STp->immediate_filemark))
2813 cmd[1] |= 1;
2814 cmd[2] = (arg >> 16);
2815 cmd[3] = (arg >> 8);
2816 cmd[4] = arg;
2817 timeout = STp->device->request_queue->rq_timeout;
2818 DEBC(
2819 if (cmd_in != MTWSM)
2820 st_printk(ST_DEB_MSG, STp,
2821 "Writing %d filemarks.\n",
2822 cmd[2] * 65536 +
2823 cmd[3] * 256 +
2824 cmd[4]);
2825 else
2826 st_printk(ST_DEB_MSG, STp,
2827 "Writing %d setmarks.\n",
2828 cmd[2] * 65536 +
2829 cmd[3] * 256 +
2830 cmd[4]);
2831 )
2832 if (fileno >= 0)
2833 fileno += arg;
2834 blkno = 0;
2835 at_sm = (cmd_in == MTWSM);
2836 break;
2837 case MTREW:
2838 cmd[0] = REZERO_UNIT;
2839 if (STp->immediate) {
2840 cmd[1] = 1; /* Don't wait for completion */
2841 timeout = STp->device->request_queue->rq_timeout;
2842 }
2843 DEBC_printk(STp, "Rewinding tape.\n");
2844 fileno = blkno = at_sm = 0;
2845 break;
2846 case MTNOP:
2847 DEBC_printk(STp, "No op on tape.\n");
2848 return 0; /* Should do something ? */
2849 case MTRETEN:
2850 cmd[0] = START_STOP;
2851 if (STp->immediate) {
2852 cmd[1] = 1; /* Don't wait for completion */
2853 timeout = STp->device->request_queue->rq_timeout;
2854 }
2855 cmd[4] = 3;
2856 DEBC_printk(STp, "Retensioning tape.\n");
2857 fileno = blkno = at_sm = 0;
2858 break;
2859 case MTEOM:
2860 if (!STp->fast_mteom) {
2861 /* space to the end of tape */
2862 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2863 fileno = STps->drv_file;
2864 if (STps->eof >= ST_EOD_1)
2865 return 0;
2866 /* The next lines would hide the number of spaced FileMarks
2867 That's why I inserted the previous lines. I had no luck
2868 with detecting EOM with FSF, so we go now to EOM.
2869 Joerg Weule */
2870 } else
2871 fileno = (-1);
2872 cmd[0] = SPACE;
2873 cmd[1] = 3;
2874 DEBC_printk(STp, "Spacing to end of recorded medium.\n");
2875 blkno = -1;
2876 at_sm = 0;
2877 break;
2878 case MTERASE:
2879 if (STp->write_prot)
2880 return (-EACCES);
2881 cmd[0] = ERASE;
2882 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2883 if (STp->immediate) {
2884 cmd[1] |= 2; /* Don't wait for completion */
2885 timeout = STp->device->request_queue->rq_timeout;
2886 }
2887 else
2888 timeout = STp->long_timeout * 8;
2889
2890 DEBC_printk(STp, "Erasing tape.\n");
2891 fileno = blkno = at_sm = 0;
2892 break;
2893 case MTSETBLK: /* Set block length */
2894 case MTSETDENSITY: /* Set tape density */
2895 case MTSETDRVBUFFER: /* Set drive buffering */
2896 case SET_DENS_AND_BLK: /* Set density and block size */
2897 chg_eof = 0;
2898 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2899 return (-EIO); /* Not allowed if data in buffer */
2900 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2901 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2902 STp->max_block > 0 &&
2903 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2904 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2905 st_printk(KERN_WARNING, STp, "Illegal block size.\n");
2906 return (-EINVAL);
2907 }
2908 cmd[0] = MODE_SELECT;
2909 if ((STp->use_pf & USE_PF))
2910 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2911 cmd[4] = datalen = 12;
2912 direction = DMA_TO_DEVICE;
2913
2914 memset((STp->buffer)->b_data, 0, 12);
2915 if (cmd_in == MTSETDRVBUFFER)
2916 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2917 else
2918 (STp->buffer)->b_data[2] =
2919 STp->drv_buffer << 4;
2920 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2921 if (cmd_in == MTSETDENSITY) {
2922 (STp->buffer)->b_data[4] = arg;
2923 STp->density_changed = 1; /* At least we tried ;-) */
2924 } else if (cmd_in == SET_DENS_AND_BLK)
2925 (STp->buffer)->b_data[4] = arg >> 24;
2926 else
2927 (STp->buffer)->b_data[4] = STp->density;
2928 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2929 ltmp = arg & MT_ST_BLKSIZE_MASK;
2930 if (cmd_in == MTSETBLK)
2931 STp->blksize_changed = 1; /* At least we tried ;-) */
2932 } else
2933 ltmp = STp->block_size;
2934 (STp->buffer)->b_data[9] = (ltmp >> 16);
2935 (STp->buffer)->b_data[10] = (ltmp >> 8);
2936 (STp->buffer)->b_data[11] = ltmp;
2937 timeout = STp->device->request_queue->rq_timeout;
2938 DEBC(
2939 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2940 st_printk(ST_DEB_MSG, STp,
2941 "Setting block size to %d bytes.\n",
2942 (STp->buffer)->b_data[9] * 65536 +
2943 (STp->buffer)->b_data[10] * 256 +
2944 (STp->buffer)->b_data[11]);
2945 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2946 st_printk(ST_DEB_MSG, STp,
2947 "Setting density code to %x.\n",
2948 (STp->buffer)->b_data[4]);
2949 if (cmd_in == MTSETDRVBUFFER)
2950 st_printk(ST_DEB_MSG, STp,
2951 "Setting drive buffer code to %d.\n",
2952 ((STp->buffer)->b_data[2] >> 4) & 7);
2953 )
2954 break;
2955 default:
2956 return (-ENOSYS);
2957 }
2958
2959 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2960 timeout, MAX_RETRIES, 1);
2961 if (!SRpnt)
2962 return (STp->buffer)->syscall_result;
2963
2964 ioctl_result = (STp->buffer)->syscall_result;
2965
2966 if (!ioctl_result) { /* SCSI command successful */
2967 st_release_request(SRpnt);
2968 SRpnt = NULL;
2969 STps->drv_block = blkno;
2970 STps->drv_file = fileno;
2971 STps->at_sm = at_sm;
2972
2973 if (cmd_in == MTBSFM)
2974 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2975 else if (cmd_in == MTFSFM)
2976 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2977
2978 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2979 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2980 if (STp->block_size != 0) {
2981 (STp->buffer)->buffer_blocks =
2982 (STp->buffer)->buffer_size / STp->block_size;
2983 }
2984 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2985 if (cmd_in == SET_DENS_AND_BLK)
2986 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2987 } else if (cmd_in == MTSETDRVBUFFER)
2988 STp->drv_buffer = (arg & 7);
2989 else if (cmd_in == MTSETDENSITY)
2990 STp->density = arg;
2991
2992 if (cmd_in == MTEOM)
2993 STps->eof = ST_EOD;
2994 else if (cmd_in == MTFSF)
2995 STps->eof = ST_FM;
2996 else if (chg_eof)
2997 STps->eof = ST_NOEOF;
2998
2999 if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
3000 STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
3001 } else { /* SCSI command was not completely successful. Don't return
3002 from this block without releasing the SCSI command block! */
3003 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
3004
3005 if (cmdstatp->flags & SENSE_EOM) {
3006 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
3007 cmd_in != MTBSR && cmd_in != MTBSS)
3008 STps->eof = ST_EOM_OK;
3009 STps->drv_block = 0;
3010 }
3011
3012 if (cmdstatp->remainder_valid)
3013 undone = (int)cmdstatp->uremainder64;
3014 else
3015 undone = 0;
3016
3017 if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
3018 cmdstatp->have_sense &&
3019 (cmdstatp->flags & SENSE_EOM)) {
3020 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
3021 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
3022 ioctl_result = 0; /* EOF(s) written successfully at EOM */
3023 STps->eof = ST_NOEOF;
3024 } else { /* Writing EOF(s) failed */
3025 if (fileno >= 0)
3026 fileno -= undone;
3027 if (undone < arg)
3028 STps->eof = ST_NOEOF;
3029 }
3030 STps->drv_file = fileno;
3031 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
3032 if (fileno >= 0)
3033 STps->drv_file = fileno - undone;
3034 else
3035 STps->drv_file = fileno;
3036 STps->drv_block = -1;
3037 STps->eof = ST_NOEOF;
3038 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
3039 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3040 undone = (-undone);
3041 if (STps->drv_file >= 0)
3042 STps->drv_file = fileno + undone;
3043 STps->drv_block = 0;
3044 STps->eof = ST_NOEOF;
3045 } else if (cmd_in == MTFSR) {
3046 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3047 if (STps->drv_file >= 0)
3048 STps->drv_file++;
3049 STps->drv_block = 0;
3050 STps->eof = ST_FM;
3051 } else {
3052 if (blkno >= undone)
3053 STps->drv_block = blkno - undone;
3054 else
3055 STps->drv_block = (-1);
3056 STps->eof = ST_NOEOF;
3057 }
3058 } else if (cmd_in == MTBSR) {
3059 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3060 STps->drv_file--;
3061 STps->drv_block = (-1);
3062 } else {
3063 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3064 undone = (-undone);
3065 if (STps->drv_block >= 0)
3066 STps->drv_block = blkno + undone;
3067 }
3068 STps->eof = ST_NOEOF;
3069 } else if (cmd_in == MTEOM) {
3070 STps->drv_file = (-1);
3071 STps->drv_block = (-1);
3072 STps->eof = ST_EOD;
3073 } else if (cmd_in == MTSETBLK ||
3074 cmd_in == MTSETDENSITY ||
3075 cmd_in == MTSETDRVBUFFER ||
3076 cmd_in == SET_DENS_AND_BLK) {
3077 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
3078 !(STp->use_pf & PF_TESTED)) {
3079 /* Try the other possible state of Page Format if not
3080 already tried */
3081 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
3082 st_release_request(SRpnt);
3083 SRpnt = NULL;
3084 return st_int_ioctl(STp, cmd_in, arg);
3085 }
3086 } else if (chg_eof)
3087 STps->eof = ST_NOEOF;
3088
3089 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
3090 STps->eof = ST_EOD;
3091
3092 st_release_request(SRpnt);
3093 SRpnt = NULL;
3094 }
3095
3096 return ioctl_result;
3097}
3098
3099
3100/* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
3101 structure. */
3102
3103static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
3104 int logical)
3105{
3106 int result;
3107 unsigned char scmd[MAX_COMMAND_SIZE];
3108 struct st_request *SRpnt;
3109
3110 if (STp->ready != ST_READY)
3111 return (-EIO);
3112
3113 memset(scmd, 0, MAX_COMMAND_SIZE);
3114 if ((STp->device)->scsi_level < SCSI_2) {
3115 scmd[0] = QFA_REQUEST_BLOCK;
3116 scmd[4] = 3;
3117 } else {
3118 scmd[0] = READ_POSITION;
3119 if (!logical && !STp->scsi2_logical)
3120 scmd[1] = 1;
3121 }
3122 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3123 STp->device->request_queue->rq_timeout,
3124 MAX_READY_RETRIES, 1);
3125 if (!SRpnt)
3126 return (STp->buffer)->syscall_result;
3127
3128 if ((STp->buffer)->syscall_result != 0 ||
3129 (STp->device->scsi_level >= SCSI_2 &&
3130 ((STp->buffer)->b_data[0] & 4) != 0)) {
3131 *block = *partition = 0;
3132 DEBC_printk(STp, " Can't read tape position.\n");
3133 result = (-EIO);
3134 } else {
3135 result = 0;
3136 if ((STp->device)->scsi_level < SCSI_2) {
3137 *block = ((STp->buffer)->b_data[0] << 16)
3138 + ((STp->buffer)->b_data[1] << 8)
3139 + (STp->buffer)->b_data[2];
3140 *partition = 0;
3141 } else {
3142 *block = ((STp->buffer)->b_data[4] << 24)
3143 + ((STp->buffer)->b_data[5] << 16)
3144 + ((STp->buffer)->b_data[6] << 8)
3145 + (STp->buffer)->b_data[7];
3146 *partition = (STp->buffer)->b_data[1];
3147 if (((STp->buffer)->b_data[0] & 0x80) &&
3148 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3149 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3150 }
3151 DEBC_printk(STp, "Got tape pos. blk %d part %d.\n",
3152 *block, *partition);
3153 }
3154 st_release_request(SRpnt);
3155 SRpnt = NULL;
3156
3157 return result;
3158}
3159
3160
3161/* Set the tape block and partition. Negative partition means that only the
3162 block should be set in vendor specific way. */
3163static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3164 int logical)
3165{
3166 struct st_partstat *STps;
3167 int result, p;
3168 unsigned int blk;
3169 int timeout;
3170 unsigned char scmd[MAX_COMMAND_SIZE];
3171 struct st_request *SRpnt;
3172
3173 if (STp->ready != ST_READY)
3174 return (-EIO);
3175 timeout = STp->long_timeout;
3176 STps = &(STp->ps[STp->partition]);
3177
3178 DEBC_printk(STp, "Setting block to %d and partition to %d.\n",
3179 block, partition);
3180 DEB(if (partition < 0)
3181 return (-EIO); )
3182
3183 /* Update the location at the partition we are leaving */
3184 if ((!STp->can_partitions && partition != 0) ||
3185 partition >= ST_NBR_PARTITIONS)
3186 return (-EINVAL);
3187 if (partition != STp->partition) {
3188 if (get_location(STp, &blk, &p, 1))
3189 STps->last_block_valid = 0;
3190 else {
3191 STps->last_block_valid = 1;
3192 STps->last_block_visited = blk;
3193 DEBC_printk(STp, "Visited block %d for "
3194 "partition %d saved.\n",
3195 blk, STp->partition);
3196 }
3197 }
3198
3199 memset(scmd, 0, MAX_COMMAND_SIZE);
3200 if ((STp->device)->scsi_level < SCSI_2) {
3201 scmd[0] = QFA_SEEK_BLOCK;
3202 scmd[2] = (block >> 16);
3203 scmd[3] = (block >> 8);
3204 scmd[4] = block;
3205 scmd[5] = 0;
3206 } else {
3207 scmd[0] = SEEK_10;
3208 scmd[3] = (block >> 24);
3209 scmd[4] = (block >> 16);
3210 scmd[5] = (block >> 8);
3211 scmd[6] = block;
3212 if (!logical && !STp->scsi2_logical)
3213 scmd[1] = 4;
3214 if (STp->partition != partition) {
3215 scmd[1] |= 2;
3216 scmd[8] = partition;
3217 DEBC_printk(STp, "Trying to change partition "
3218 "from %d to %d\n", STp->partition,
3219 partition);
3220 }
3221 }
3222 if (STp->immediate) {
3223 scmd[1] |= 1; /* Don't wait for completion */
3224 timeout = STp->device->request_queue->rq_timeout;
3225 }
3226
3227 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3228 timeout, MAX_READY_RETRIES, 1);
3229 if (!SRpnt)
3230 return (STp->buffer)->syscall_result;
3231
3232 STps->drv_block = STps->drv_file = (-1);
3233 STps->eof = ST_NOEOF;
3234 if ((STp->buffer)->syscall_result != 0) {
3235 result = (-EIO);
3236 if (STp->can_partitions &&
3237 (STp->device)->scsi_level >= SCSI_2 &&
3238 (p = find_partition(STp)) >= 0)
3239 STp->partition = p;
3240 } else {
3241 if (STp->can_partitions) {
3242 STp->partition = partition;
3243 STps = &(STp->ps[partition]);
3244 if (!STps->last_block_valid ||
3245 STps->last_block_visited != block) {
3246 STps->at_sm = 0;
3247 STps->rw = ST_IDLE;
3248 }
3249 } else
3250 STps->at_sm = 0;
3251 if (block == 0)
3252 STps->drv_block = STps->drv_file = 0;
3253 result = 0;
3254 }
3255
3256 st_release_request(SRpnt);
3257 SRpnt = NULL;
3258
3259 return result;
3260}
3261
3262
3263/* Find the current partition number for the drive status. Called from open and
3264 returns either partition number of negative error code. */
3265static int find_partition(struct scsi_tape *STp)
3266{
3267 int i, partition;
3268 unsigned int block;
3269
3270 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3271 return i;
3272 if (partition >= ST_NBR_PARTITIONS)
3273 return (-EIO);
3274 return partition;
3275}
3276
3277
3278/* Change the partition if necessary */
3279static int switch_partition(struct scsi_tape *STp)
3280{
3281 struct st_partstat *STps;
3282
3283 if (STp->partition == STp->new_partition)
3284 return 0;
3285 STps = &(STp->ps[STp->new_partition]);
3286 if (!STps->last_block_valid)
3287 STps->last_block_visited = 0;
3288 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3289}
3290
3291/* Functions for reading and writing the medium partition mode page. */
3292
3293#define PART_PAGE 0x11
3294#define PART_PAGE_FIXED_LENGTH 8
3295
3296#define PP_OFF_MAX_ADD_PARTS 2
3297#define PP_OFF_NBR_ADD_PARTS 3
3298#define PP_OFF_FLAGS 4
3299#define PP_OFF_PART_UNITS 6
3300#define PP_OFF_RESERVED 7
3301
3302#define PP_BIT_IDP 0x20
3303#define PP_BIT_FDP 0x80
3304#define PP_MSK_PSUM_MB 0x10
3305#define PP_MSK_PSUM_UNITS 0x18
3306#define PP_MSK_POFM 0x04
3307
3308/* Get the number of partitions on the tape. As a side effect reads the
3309 mode page into the tape buffer. */
3310static int nbr_partitions(struct scsi_tape *STp)
3311{
3312 int result;
3313
3314 if (STp->ready != ST_READY)
3315 return (-EIO);
3316
3317 result = read_mode_page(STp, PART_PAGE, 1);
3318
3319 if (result) {
3320 DEBC_printk(STp, "Can't read medium partition page.\n");
3321 result = (-EIO);
3322 } else {
3323 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3324 PP_OFF_NBR_ADD_PARTS] + 1;
3325 DEBC_printk(STp, "Number of partitions %d.\n", result);
3326 }
3327
3328 return result;
3329}
3330
3331
3332static int format_medium(struct scsi_tape *STp, int format)
3333{
3334 int result = 0;
3335 int timeout = STp->long_timeout;
3336 unsigned char scmd[MAX_COMMAND_SIZE];
3337 struct st_request *SRpnt;
3338
3339 memset(scmd, 0, MAX_COMMAND_SIZE);
3340 scmd[0] = FORMAT_UNIT;
3341 scmd[2] = format;
3342 if (STp->immediate) {
3343 scmd[1] |= 1; /* Don't wait for completion */
3344 timeout = STp->device->request_queue->rq_timeout;
3345 }
3346 DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
3347 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3348 timeout, MAX_RETRIES, 1);
3349 if (!SRpnt)
3350 result = STp->buffer->syscall_result;
3351 return result;
3352}
3353
3354
3355/* Partition the tape into two partitions if size > 0 or one partition if
3356 size == 0.
3357
3358 The block descriptors are read and written because Sony SDT-7000 does not
3359 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3360
3361 My HP C1533A drive returns only one partition size field. This is used to
3362 set the size of partition 1. There is no size field for the default partition.
3363 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3364 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3365 The following algorithm is used to accommodate both drives: if the number of
3366 partition size fields is greater than the maximum number of additional partitions
3367 in the mode page, the second field is used. Otherwise the first field is used.
3368
3369 For Seagate DDS drives the page length must be 8 when no partitions is defined
3370 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3371 is acceptable also to some other old drives and enforced if the first partition
3372 size field is used for the first additional partition size.
3373
3374 For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
3375 */
3376static int partition_tape(struct scsi_tape *STp, int size)
3377{
3378 int result;
3379 int target_partition;
3380 bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
3381 int pgo, psd_cnt, psdo;
3382 int psum = PP_MSK_PSUM_MB, units = 0;
3383 unsigned char *bp;
3384
3385 result = read_mode_page(STp, PART_PAGE, 0);
3386 if (result) {
3387 DEBC_printk(STp, "Can't read partition mode page.\n");
3388 return result;
3389 }
3390 target_partition = 1;
3391 if (size < 0) {
3392 target_partition = 0;
3393 size = -size;
3394 }
3395
3396 /* The mode page is in the buffer. Let's modify it and write it. */
3397 bp = (STp->buffer)->b_data;
3398 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3399 DEBC_printk(STp, "Partition page length is %d bytes.\n",
3400 bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
3401
3402 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3403
3404 if (scsi3) {
3405 needs_format = (bp[pgo + PP_OFF_FLAGS] & PP_MSK_POFM) != 0;
3406 if (needs_format && size == 0) {
3407 /* No need to write the mode page when clearing
3408 * partitioning
3409 */
3410 DEBC_printk(STp, "Formatting tape with one partition.\n");
3411 result = format_medium(STp, 0);
3412 goto out;
3413 }
3414 if (needs_format) /* Leave the old value for HP DATs claiming SCSI_3 */
3415 psd_cnt = 2;
3416 if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) == PP_MSK_PSUM_UNITS) {
3417 /* Use units scaling for large partitions if the device
3418 * suggests it and no precision lost. Required for IBM
3419 * TS1140/50 drives that don't support MB units.
3420 */
3421 if (size >= 1000 && (size % 1000) == 0) {
3422 size /= 1000;
3423 psum = PP_MSK_PSUM_UNITS;
3424 units = 9; /* GB */
3425 }
3426 }
3427 /* Try it anyway if too large to specify in MB */
3428 if (psum == PP_MSK_PSUM_MB && size >= 65534) {
3429 size /= 1000;
3430 psum = PP_MSK_PSUM_UNITS;
3431 units = 9; /* GB */
3432 }
3433 }
3434
3435 if (size >= 65535 || /* Does not fit into two bytes */
3436 (target_partition == 0 && psd_cnt < 2)) {
3437 result = -EINVAL;
3438 goto out;
3439 }
3440
3441 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3442 /* The second condition is for HP DDS which use only one partition size
3443 * descriptor
3444 */
3445 if (target_partition > 0 &&
3446 (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS] ||
3447 bp[pgo + PP_OFF_MAX_ADD_PARTS] != 1)) {
3448 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest to partition 0 */
3449 psdo += 2;
3450 }
3451 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3452
3453 DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
3454 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3455 bp[pgo + PP_OFF_NBR_ADD_PARTS]);
3456
3457 if (size == 0) {
3458 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3459 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3460 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3461 DEBC_printk(STp, "Formatting tape with one partition.\n");
3462 } else {
3463 bp[psdo] = (size >> 8) & 0xff;
3464 bp[psdo + 1] = size & 0xff;
3465 if (target_partition == 0)
3466 bp[psdo + 2] = bp[psdo + 3] = 0xff;
3467 bp[pgo + 3] = 1;
3468 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3469 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3470 DEBC_printk(STp,
3471 "Formatting tape with two partitions (%i = %d MB).\n",
3472 target_partition, units > 0 ? size * 1000 : size);
3473 }
3474 bp[pgo + PP_OFF_PART_UNITS] = 0;
3475 bp[pgo + PP_OFF_RESERVED] = 0;
3476 if (size != 1 || units != 0) {
3477 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
3478 (bp[pgo + PP_OFF_FLAGS] & 0x07);
3479 bp[pgo + PP_OFF_PART_UNITS] = units;
3480 } else
3481 bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
3482 (bp[pgo + PP_OFF_FLAGS] & 0x1f);
3483 bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
3484
3485 result = write_mode_page(STp, PART_PAGE, 1);
3486
3487 if (!result && needs_format)
3488 result = format_medium(STp, 1);
3489
3490 if (result) {
3491 st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
3492 result = (-EIO);
3493 }
3494
3495out:
3496 return result;
3497}
3498
3499
3500
3501/* The ioctl command */
3502static long st_ioctl_common(struct file *file, unsigned int cmd_in, void __user *p)
3503{
3504 int i, cmd_nr, cmd_type, bt;
3505 int retval = 0;
3506 unsigned int blk;
3507 struct scsi_tape *STp = file->private_data;
3508 struct st_modedef *STm;
3509 struct st_partstat *STps;
3510
3511 if (mutex_lock_interruptible(&STp->lock))
3512 return -ERESTARTSYS;
3513
3514 DEB(
3515 if (debugging && !STp->in_use) {
3516 st_printk(ST_DEB_MSG, STp, "Incorrect device.\n");
3517 retval = (-EIO);
3518 goto out;
3519 } ) /* end DEB */
3520
3521 STm = &(STp->modes[STp->current_mode]);
3522 STps = &(STp->ps[STp->partition]);
3523
3524 /*
3525 * If we are in the middle of error recovery, don't let anyone
3526 * else try and use this device. Also, if error recovery fails, it
3527 * may try and take the device offline, in which case all further
3528 * access to the device is prohibited.
3529 */
3530 retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
3531 file->f_flags & O_NDELAY);
3532 if (retval)
3533 goto out;
3534
3535 cmd_type = _IOC_TYPE(cmd_in);
3536 cmd_nr = _IOC_NR(cmd_in);
3537
3538 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3539 struct mtop mtc;
3540
3541 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3542 retval = (-EINVAL);
3543 goto out;
3544 }
3545
3546 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3547 if (i) {
3548 retval = (-EFAULT);
3549 goto out;
3550 }
3551
3552 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3553 st_printk(KERN_WARNING, STp,
3554 "MTSETDRVBUFFER only allowed for root.\n");
3555 retval = (-EPERM);
3556 goto out;
3557 }
3558 if (!STm->defined &&
3559 (mtc.mt_op != MTSETDRVBUFFER &&
3560 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3561 retval = (-ENXIO);
3562 goto out;
3563 }
3564
3565 if (!STp->pos_unknown) {
3566
3567 if (STps->eof == ST_FM_HIT) {
3568 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3569 mtc.mt_op == MTEOM) {
3570 mtc.mt_count -= 1;
3571 if (STps->drv_file >= 0)
3572 STps->drv_file += 1;
3573 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3574 mtc.mt_count += 1;
3575 if (STps->drv_file >= 0)
3576 STps->drv_file += 1;
3577 }
3578 }
3579
3580 if (mtc.mt_op == MTSEEK) {
3581 /* Old position must be restored if partition will be
3582 changed */
3583 i = !STp->can_partitions ||
3584 (STp->new_partition != STp->partition);
3585 } else {
3586 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3587 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3588 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3589 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3590 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3591 mtc.mt_op == MTCOMPRESSION;
3592 }
3593 i = flush_buffer(STp, i);
3594 if (i < 0) {
3595 retval = i;
3596 goto out;
3597 }
3598 if (STps->rw == ST_WRITING &&
3599 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3600 mtc.mt_op == MTSEEK ||
3601 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3602 i = st_int_ioctl(STp, MTWEOF, 1);
3603 if (i < 0) {
3604 retval = i;
3605 goto out;
3606 }
3607 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3608 mtc.mt_count++;
3609 STps->rw = ST_IDLE;
3610 }
3611
3612 } else {
3613 /*
3614 * If there was a bus reset, block further access
3615 * to this device. If the user wants to rewind the tape,
3616 * then reset the flag and allow access again.
3617 */
3618 if (mtc.mt_op != MTREW &&
3619 mtc.mt_op != MTOFFL &&
3620 mtc.mt_op != MTRETEN &&
3621 mtc.mt_op != MTERASE &&
3622 mtc.mt_op != MTSEEK &&
3623 mtc.mt_op != MTEOM) {
3624 retval = (-EIO);
3625 goto out;
3626 }
3627 reset_state(STp);
3628 /* remove this when the midlevel properly clears was_reset */
3629 STp->device->was_reset = 0;
3630 }
3631
3632 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3633 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3634 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3635 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3636
3637 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3638 do_door_lock(STp, 0); /* Ignore result! */
3639
3640 if (mtc.mt_op == MTSETDRVBUFFER &&
3641 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3642 retval = st_set_options(STp, mtc.mt_count);
3643 goto out;
3644 }
3645
3646 if (mtc.mt_op == MTSETPART) {
3647 if (!STp->can_partitions ||
3648 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3649 retval = (-EINVAL);
3650 goto out;
3651 }
3652 if (mtc.mt_count >= STp->nbr_partitions &&
3653 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3654 retval = (-EIO);
3655 goto out;
3656 }
3657 if (mtc.mt_count >= STp->nbr_partitions) {
3658 retval = (-EINVAL);
3659 goto out;
3660 }
3661 STp->new_partition = mtc.mt_count;
3662 retval = 0;
3663 goto out;
3664 }
3665
3666 if (mtc.mt_op == MTMKPART) {
3667 if (!STp->can_partitions) {
3668 retval = (-EINVAL);
3669 goto out;
3670 }
3671 i = do_load_unload(STp, file, 1);
3672 if (i < 0) {
3673 retval = i;
3674 goto out;
3675 }
3676 i = partition_tape(STp, mtc.mt_count);
3677 if (i < 0) {
3678 retval = i;
3679 goto out;
3680 }
3681 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3682 STp->ps[i].rw = ST_IDLE;
3683 STp->ps[i].at_sm = 0;
3684 STp->ps[i].last_block_valid = 0;
3685 }
3686 STp->partition = STp->new_partition = 0;
3687 STp->nbr_partitions = mtc.mt_count != 0 ? 2 : 1;
3688 STps->drv_block = STps->drv_file = 0;
3689 retval = 0;
3690 goto out;
3691 }
3692
3693 if (mtc.mt_op == MTSEEK) {
3694 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3695 if (!STp->can_partitions)
3696 STp->ps[0].rw = ST_IDLE;
3697 retval = i;
3698 goto out;
3699 }
3700
3701 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3702 retval = do_load_unload(STp, file, 0);
3703 goto out;
3704 }
3705
3706 if (mtc.mt_op == MTLOAD) {
3707 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3708 goto out;
3709 }
3710
3711 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3712 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3713 goto out;
3714 }
3715
3716 if (STp->can_partitions && STp->ready == ST_READY &&
3717 (i = switch_partition(STp)) < 0) {
3718 retval = i;
3719 goto out;
3720 }
3721
3722 if (mtc.mt_op == MTCOMPRESSION)
3723 retval = st_compression(STp, (mtc.mt_count & 1));
3724 else
3725 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3726 goto out;
3727 }
3728 if (!STm->defined) {
3729 retval = (-ENXIO);
3730 goto out;
3731 }
3732
3733 if ((i = flush_buffer(STp, 0)) < 0) {
3734 retval = i;
3735 goto out;
3736 }
3737 if (STp->can_partitions &&
3738 (i = switch_partition(STp)) < 0) {
3739 retval = i;
3740 goto out;
3741 }
3742
3743 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3744 struct mtget mt_status;
3745
3746 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3747 retval = (-EINVAL);
3748 goto out;
3749 }
3750
3751 mt_status.mt_type = STp->tape_type;
3752 mt_status.mt_dsreg =
3753 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3754 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3755 mt_status.mt_blkno = STps->drv_block;
3756 mt_status.mt_fileno = STps->drv_file;
3757 if (STp->block_size != 0) {
3758 if (STps->rw == ST_WRITING)
3759 mt_status.mt_blkno +=
3760 (STp->buffer)->buffer_bytes / STp->block_size;
3761 else if (STps->rw == ST_READING)
3762 mt_status.mt_blkno -=
3763 ((STp->buffer)->buffer_bytes +
3764 STp->block_size - 1) / STp->block_size;
3765 }
3766
3767 mt_status.mt_gstat = 0;
3768 if (STp->drv_write_prot)
3769 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3770 if (mt_status.mt_blkno == 0) {
3771 if (mt_status.mt_fileno == 0)
3772 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3773 else
3774 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3775 }
3776 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3777 mt_status.mt_resid = STp->partition;
3778 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3779 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3780 else if (STps->eof >= ST_EOM_OK)
3781 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3782 if (STp->density == 1)
3783 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3784 else if (STp->density == 2)
3785 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3786 else if (STp->density == 3)
3787 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3788 if (STp->ready == ST_READY)
3789 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3790 if (STp->ready == ST_NO_TAPE)
3791 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3792 if (STps->at_sm)
3793 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3794 if (STm->do_async_writes ||
3795 (STm->do_buffer_writes && STp->block_size != 0) ||
3796 STp->drv_buffer != 0)
3797 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3798 if (STp->cleaning_req)
3799 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3800
3801 retval = put_user_mtget(p, &mt_status);
3802 if (retval)
3803 goto out;
3804
3805 STp->recover_reg = 0; /* Clear after read */
3806 goto out;
3807 } /* End of MTIOCGET */
3808 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3809 struct mtpos mt_pos;
3810 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3811 retval = (-EINVAL);
3812 goto out;
3813 }
3814 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3815 retval = i;
3816 goto out;
3817 }
3818 mt_pos.mt_blkno = blk;
3819 retval = put_user_mtpos(p, &mt_pos);
3820 goto out;
3821 }
3822 mutex_unlock(&STp->lock);
3823 switch (cmd_in) {
3824 case SCSI_IOCTL_STOP_UNIT:
3825 /* unload */
3826 retval = scsi_ioctl(STp->device, cmd_in, p);
3827 if (!retval) {
3828 STp->rew_at_close = 0;
3829 STp->ready = ST_NO_TAPE;
3830 }
3831 return retval;
3832
3833 case SCSI_IOCTL_GET_IDLUN:
3834 case SCSI_IOCTL_GET_BUS_NUMBER:
3835 break;
3836
3837 default:
3838 if ((cmd_in == SG_IO ||
3839 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3840 cmd_in == CDROM_SEND_PACKET) &&
3841 !capable(CAP_SYS_RAWIO))
3842 i = -EPERM;
3843 else
3844 i = scsi_cmd_ioctl(STp->disk->queue, STp->disk,
3845 file->f_mode, cmd_in, p);
3846 if (i != -ENOTTY)
3847 return i;
3848 break;
3849 }
3850 return -ENOTTY;
3851
3852 out:
3853 mutex_unlock(&STp->lock);
3854 return retval;
3855}
3856
3857static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3858{
3859 void __user *p = (void __user *)arg;
3860 struct scsi_tape *STp = file->private_data;
3861 int ret;
3862
3863 ret = st_ioctl_common(file, cmd_in, p);
3864 if (ret != -ENOTTY)
3865 return ret;
3866
3867 return scsi_ioctl(STp->device, cmd_in, p);
3868}
3869
3870#ifdef CONFIG_COMPAT
3871static long st_compat_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3872{
3873 void __user *p = compat_ptr(arg);
3874 struct scsi_tape *STp = file->private_data;
3875 int ret;
3876
3877 /* argument conversion is handled using put_user_mtpos/put_user_mtget */
3878 switch (cmd_in) {
3879 case MTIOCPOS32:
3880 return st_ioctl_common(file, MTIOCPOS, p);
3881 case MTIOCGET32:
3882 return st_ioctl_common(file, MTIOCGET, p);
3883 }
3884
3885 ret = st_ioctl_common(file, cmd_in, p);
3886 if (ret != -ENOTTY)
3887 return ret;
3888
3889 return scsi_compat_ioctl(STp->device, cmd_in, p);
3890}
3891#endif
3892
3893
3894
3895/* Try to allocate a new tape buffer. Calling function must not hold
3896 dev_arr_lock. */
3897static struct st_buffer *new_tape_buffer(int max_sg)
3898{
3899 struct st_buffer *tb;
3900
3901 tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
3902 if (!tb) {
3903 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3904 return NULL;
3905 }
3906 tb->frp_segs = 0;
3907 tb->use_sg = max_sg;
3908 tb->buffer_size = 0;
3909
3910 tb->reserved_pages = kcalloc(max_sg, sizeof(struct page *),
3911 GFP_KERNEL);
3912 if (!tb->reserved_pages) {
3913 kfree(tb);
3914 return NULL;
3915 }
3916
3917 return tb;
3918}
3919
3920
3921/* Try to allocate enough space in the tape buffer */
3922#define ST_MAX_ORDER 6
3923
3924static int enlarge_buffer(struct st_buffer * STbuffer, int new_size)
3925{
3926 int segs, max_segs, b_size, order, got;
3927 gfp_t priority;
3928
3929 if (new_size <= STbuffer->buffer_size)
3930 return 1;
3931
3932 if (STbuffer->buffer_size <= PAGE_SIZE)
3933 normalize_buffer(STbuffer); /* Avoid extra segment */
3934
3935 max_segs = STbuffer->use_sg;
3936
3937 priority = GFP_KERNEL | __GFP_NOWARN;
3938
3939 if (STbuffer->cleared)
3940 priority |= __GFP_ZERO;
3941
3942 if (STbuffer->frp_segs) {
3943 order = STbuffer->reserved_page_order;
3944 b_size = PAGE_SIZE << order;
3945 } else {
3946 for (b_size = PAGE_SIZE, order = 0;
3947 order < ST_MAX_ORDER &&
3948 max_segs * (PAGE_SIZE << order) < new_size;
3949 order++, b_size *= 2)
3950 ; /* empty */
3951 STbuffer->reserved_page_order = order;
3952 }
3953 if (max_segs * (PAGE_SIZE << order) < new_size) {
3954 if (order == ST_MAX_ORDER)
3955 return 0;
3956 normalize_buffer(STbuffer);
3957 return enlarge_buffer(STbuffer, new_size);
3958 }
3959
3960 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3961 segs < max_segs && got < new_size;) {
3962 struct page *page;
3963
3964 page = alloc_pages(priority, order);
3965 if (!page) {
3966 DEB(STbuffer->buffer_size = got);
3967 normalize_buffer(STbuffer);
3968 return 0;
3969 }
3970
3971 STbuffer->frp_segs += 1;
3972 got += b_size;
3973 STbuffer->buffer_size = got;
3974 STbuffer->reserved_pages[segs] = page;
3975 segs++;
3976 }
3977 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3978
3979 return 1;
3980}
3981
3982
3983/* Make sure that no data from previous user is in the internal buffer */
3984static void clear_buffer(struct st_buffer * st_bp)
3985{
3986 int i;
3987
3988 for (i=0; i < st_bp->frp_segs; i++)
3989 memset(page_address(st_bp->reserved_pages[i]), 0,
3990 PAGE_SIZE << st_bp->reserved_page_order);
3991 st_bp->cleared = 1;
3992}
3993
3994
3995/* Release the extra buffer */
3996static void normalize_buffer(struct st_buffer * STbuffer)
3997{
3998 int i, order = STbuffer->reserved_page_order;
3999
4000 for (i = 0; i < STbuffer->frp_segs; i++) {
4001 __free_pages(STbuffer->reserved_pages[i], order);
4002 STbuffer->buffer_size -= (PAGE_SIZE << order);
4003 }
4004 STbuffer->frp_segs = 0;
4005 STbuffer->sg_segs = 0;
4006 STbuffer->reserved_page_order = 0;
4007 STbuffer->map_data.offset = 0;
4008}
4009
4010
4011/* Move data from the user buffer to the tape buffer. Returns zero (success) or
4012 negative error code. */
4013static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
4014{
4015 int i, cnt, res, offset;
4016 int length = PAGE_SIZE << st_bp->reserved_page_order;
4017
4018 for (i = 0, offset = st_bp->buffer_bytes;
4019 i < st_bp->frp_segs && offset >= length; i++)
4020 offset -= length;
4021 if (i == st_bp->frp_segs) { /* Should never happen */
4022 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
4023 return (-EIO);
4024 }
4025 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4026 struct page *page = st_bp->reserved_pages[i];
4027 cnt = length - offset < do_count ? length - offset : do_count;
4028 res = copy_from_user(page_address(page) + offset, ubp, cnt);
4029 if (res)
4030 return (-EFAULT);
4031 do_count -= cnt;
4032 st_bp->buffer_bytes += cnt;
4033 ubp += cnt;
4034 offset = 0;
4035 }
4036 if (do_count) /* Should never happen */
4037 return (-EIO);
4038
4039 return 0;
4040}
4041
4042
4043/* Move data from the tape buffer to the user buffer. Returns zero (success) or
4044 negative error code. */
4045static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
4046{
4047 int i, cnt, res, offset;
4048 int length = PAGE_SIZE << st_bp->reserved_page_order;
4049
4050 for (i = 0, offset = st_bp->read_pointer;
4051 i < st_bp->frp_segs && offset >= length; i++)
4052 offset -= length;
4053 if (i == st_bp->frp_segs) { /* Should never happen */
4054 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
4055 return (-EIO);
4056 }
4057 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4058 struct page *page = st_bp->reserved_pages[i];
4059 cnt = length - offset < do_count ? length - offset : do_count;
4060 res = copy_to_user(ubp, page_address(page) + offset, cnt);
4061 if (res)
4062 return (-EFAULT);
4063 do_count -= cnt;
4064 st_bp->buffer_bytes -= cnt;
4065 st_bp->read_pointer += cnt;
4066 ubp += cnt;
4067 offset = 0;
4068 }
4069 if (do_count) /* Should never happen */
4070 return (-EIO);
4071
4072 return 0;
4073}
4074
4075
4076/* Move data towards start of buffer */
4077static void move_buffer_data(struct st_buffer * st_bp, int offset)
4078{
4079 int src_seg, dst_seg, src_offset = 0, dst_offset;
4080 int count, total;
4081 int length = PAGE_SIZE << st_bp->reserved_page_order;
4082
4083 if (offset == 0)
4084 return;
4085
4086 total=st_bp->buffer_bytes - offset;
4087 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
4088 src_offset = offset;
4089 if (src_offset < length)
4090 break;
4091 offset -= length;
4092 }
4093
4094 st_bp->buffer_bytes = st_bp->read_pointer = total;
4095 for (dst_seg=dst_offset=0; total > 0; ) {
4096 struct page *dpage = st_bp->reserved_pages[dst_seg];
4097 struct page *spage = st_bp->reserved_pages[src_seg];
4098
4099 count = min(length - dst_offset, length - src_offset);
4100 memmove(page_address(dpage) + dst_offset,
4101 page_address(spage) + src_offset, count);
4102 src_offset += count;
4103 if (src_offset >= length) {
4104 src_seg++;
4105 src_offset = 0;
4106 }
4107 dst_offset += count;
4108 if (dst_offset >= length) {
4109 dst_seg++;
4110 dst_offset = 0;
4111 }
4112 total -= count;
4113 }
4114}
4115
4116/* Validate the options from command line or module parameters */
4117static void validate_options(void)
4118{
4119 if (buffer_kbs > 0)
4120 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
4121 if (max_sg_segs >= ST_FIRST_SG)
4122 st_max_sg_segs = max_sg_segs;
4123}
4124
4125#ifndef MODULE
4126/* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
4127 */
4128static int __init st_setup(char *str)
4129{
4130 int i, len, ints[5];
4131 char *stp;
4132
4133 stp = get_options(str, ARRAY_SIZE(ints), ints);
4134
4135 if (ints[0] > 0) {
4136 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
4137 if (parms[i].val)
4138 *parms[i].val = ints[i + 1];
4139 } else {
4140 while (stp != NULL) {
4141 for (i = 0; i < ARRAY_SIZE(parms); i++) {
4142 len = strlen(parms[i].name);
4143 if (!strncmp(stp, parms[i].name, len) &&
4144 (*(stp + len) == ':' || *(stp + len) == '=')) {
4145 if (parms[i].val)
4146 *parms[i].val =
4147 simple_strtoul(stp + len + 1, NULL, 0);
4148 else
4149 printk(KERN_WARNING "st: Obsolete parameter %s\n",
4150 parms[i].name);
4151 break;
4152 }
4153 }
4154 if (i >= ARRAY_SIZE(parms))
4155 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
4156 stp);
4157 stp = strchr(stp, ',');
4158 if (stp)
4159 stp++;
4160 }
4161 }
4162
4163 validate_options();
4164
4165 return 1;
4166}
4167
4168__setup("st=", st_setup);
4169
4170#endif
4171
4172static const struct file_operations st_fops =
4173{
4174 .owner = THIS_MODULE,
4175 .read = st_read,
4176 .write = st_write,
4177 .unlocked_ioctl = st_ioctl,
4178#ifdef CONFIG_COMPAT
4179 .compat_ioctl = st_compat_ioctl,
4180#endif
4181 .open = st_open,
4182 .flush = st_flush,
4183 .release = st_release,
4184 .llseek = noop_llseek,
4185};
4186
4187static int create_one_cdev(struct scsi_tape *tape, int mode, int rew)
4188{
4189 int i, error;
4190 dev_t cdev_devno;
4191 struct cdev *cdev;
4192 struct device *dev;
4193 struct st_modedef *STm = &(tape->modes[mode]);
4194 char name[10];
4195 int dev_num = tape->index;
4196
4197 cdev_devno = MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, rew));
4198
4199 cdev = cdev_alloc();
4200 if (!cdev) {
4201 pr_err("st%d: out of memory. Device not attached.\n", dev_num);
4202 error = -ENOMEM;
4203 goto out;
4204 }
4205 cdev->owner = THIS_MODULE;
4206 cdev->ops = &st_fops;
4207 STm->cdevs[rew] = cdev;
4208
4209 error = cdev_add(cdev, cdev_devno, 1);
4210 if (error) {
4211 pr_err("st%d: Can't add %s-rewind mode %d\n", dev_num,
4212 rew ? "non" : "auto", mode);
4213 pr_err("st%d: Device not attached.\n", dev_num);
4214 goto out_free;
4215 }
4216
4217 i = mode << (4 - ST_NBR_MODE_BITS);
4218 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4219 tape->disk->disk_name, st_formats[i]);
4220
4221 dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,
4222 cdev_devno, &tape->modes[mode], "%s", name);
4223 if (IS_ERR(dev)) {
4224 pr_err("st%d: device_create failed\n", dev_num);
4225 error = PTR_ERR(dev);
4226 goto out_free;
4227 }
4228
4229 STm->devs[rew] = dev;
4230
4231 return 0;
4232out_free:
4233 cdev_del(STm->cdevs[rew]);
4234out:
4235 STm->cdevs[rew] = NULL;
4236 STm->devs[rew] = NULL;
4237 return error;
4238}
4239
4240static int create_cdevs(struct scsi_tape *tape)
4241{
4242 int mode, error;
4243 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4244 error = create_one_cdev(tape, mode, 0);
4245 if (error)
4246 return error;
4247 error = create_one_cdev(tape, mode, 1);
4248 if (error)
4249 return error;
4250 }
4251
4252 return sysfs_create_link(&tape->device->sdev_gendev.kobj,
4253 &tape->modes[0].devs[0]->kobj, "tape");
4254}
4255
4256static void remove_cdevs(struct scsi_tape *tape)
4257{
4258 int mode, rew;
4259 sysfs_remove_link(&tape->device->sdev_gendev.kobj, "tape");
4260 for (mode = 0; mode < ST_NBR_MODES; mode++) {
4261 struct st_modedef *STm = &(tape->modes[mode]);
4262 for (rew = 0; rew < 2; rew++) {
4263 if (STm->cdevs[rew])
4264 cdev_del(STm->cdevs[rew]);
4265 if (STm->devs[rew])
4266 device_unregister(STm->devs[rew]);
4267 }
4268 }
4269}
4270
4271static int st_probe(struct device *dev)
4272{
4273 struct scsi_device *SDp = to_scsi_device(dev);
4274 struct gendisk *disk = NULL;
4275 struct scsi_tape *tpnt = NULL;
4276 struct st_modedef *STm;
4277 struct st_partstat *STps;
4278 struct st_buffer *buffer;
4279 int i, error;
4280 char *stp;
4281
4282 if (SDp->type != TYPE_TAPE)
4283 return -ENODEV;
4284 if ((stp = st_incompatible(SDp))) {
4285 sdev_printk(KERN_INFO, SDp,
4286 "OnStream tapes are no longer supported;\n");
4287 sdev_printk(KERN_INFO, SDp,
4288 "please mail to linux-scsi@vger.kernel.org.\n");
4289 return -ENODEV;
4290 }
4291
4292 scsi_autopm_get_device(SDp);
4293 i = queue_max_segments(SDp->request_queue);
4294 if (st_max_sg_segs < i)
4295 i = st_max_sg_segs;
4296 buffer = new_tape_buffer(i);
4297 if (buffer == NULL) {
4298 sdev_printk(KERN_ERR, SDp,
4299 "st: Can't allocate new tape buffer. "
4300 "Device not attached.\n");
4301 goto out;
4302 }
4303
4304 disk = alloc_disk(1);
4305 if (!disk) {
4306 sdev_printk(KERN_ERR, SDp,
4307 "st: out of memory. Device not attached.\n");
4308 goto out_buffer_free;
4309 }
4310
4311 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);
4312 if (tpnt == NULL) {
4313 sdev_printk(KERN_ERR, SDp,
4314 "st: Can't allocate device descriptor.\n");
4315 goto out_put_disk;
4316 }
4317 kref_init(&tpnt->kref);
4318 tpnt->disk = disk;
4319 disk->private_data = &tpnt->driver;
4320 /* SCSI tape doesn't register this gendisk via add_disk(). Manually
4321 * take queue reference that release_disk() expects. */
4322 if (!blk_get_queue(SDp->request_queue))
4323 goto out_put_disk;
4324 disk->queue = SDp->request_queue;
4325 tpnt->driver = &st_template;
4326
4327 tpnt->device = SDp;
4328 if (SDp->scsi_level <= 2)
4329 tpnt->tape_type = MT_ISSCSI1;
4330 else
4331 tpnt->tape_type = MT_ISSCSI2;
4332
4333 tpnt->buffer = buffer;
4334 tpnt->buffer->last_SRpnt = NULL;
4335
4336 tpnt->inited = 0;
4337 tpnt->dirty = 0;
4338 tpnt->in_use = 0;
4339 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
4340 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
4341 tpnt->density = 0;
4342 tpnt->do_auto_lock = ST_AUTO_LOCK;
4343 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
4344 tpnt->can_partitions = 0;
4345 tpnt->two_fm = ST_TWO_FM;
4346 tpnt->fast_mteom = ST_FAST_MTEOM;
4347 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
4348 tpnt->sili = ST_SILI;
4349 tpnt->immediate = ST_NOWAIT;
4350 tpnt->immediate_filemark = 0;
4351 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
4352 tpnt->partition = 0;
4353 tpnt->new_partition = 0;
4354 tpnt->nbr_partitions = 0;
4355 blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
4356 tpnt->long_timeout = ST_LONG_TIMEOUT;
4357 tpnt->try_dio = try_direct_io;
4358
4359 for (i = 0; i < ST_NBR_MODES; i++) {
4360 STm = &(tpnt->modes[i]);
4361 STm->defined = 0;
4362 STm->sysv = ST_SYSV;
4363 STm->defaults_for_writes = 0;
4364 STm->do_async_writes = ST_ASYNC_WRITES;
4365 STm->do_buffer_writes = ST_BUFFER_WRITES;
4366 STm->do_read_ahead = ST_READ_AHEAD;
4367 STm->default_compression = ST_DONT_TOUCH;
4368 STm->default_blksize = (-1); /* No forced size */
4369 STm->default_density = (-1); /* No forced density */
4370 STm->tape = tpnt;
4371 }
4372
4373 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4374 STps = &(tpnt->ps[i]);
4375 STps->rw = ST_IDLE;
4376 STps->eof = ST_NOEOF;
4377 STps->at_sm = 0;
4378 STps->last_block_valid = 0;
4379 STps->drv_block = (-1);
4380 STps->drv_file = (-1);
4381 }
4382
4383 tpnt->current_mode = 0;
4384 tpnt->modes[0].defined = 1;
4385
4386 tpnt->density_changed = tpnt->compression_changed =
4387 tpnt->blksize_changed = 0;
4388 mutex_init(&tpnt->lock);
4389
4390 idr_preload(GFP_KERNEL);
4391 spin_lock(&st_index_lock);
4392 error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
4393 spin_unlock(&st_index_lock);
4394 idr_preload_end();
4395 if (error < 0) {
4396 pr_warn("st: idr allocation failed: %d\n", error);
4397 goto out_put_queue;
4398 }
4399 tpnt->index = error;
4400 sprintf(disk->disk_name, "st%d", tpnt->index);
4401 tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);
4402 if (tpnt->stats == NULL) {
4403 sdev_printk(KERN_ERR, SDp,
4404 "st: Can't allocate statistics.\n");
4405 goto out_idr_remove;
4406 }
4407
4408 dev_set_drvdata(dev, tpnt);
4409
4410
4411 error = create_cdevs(tpnt);
4412 if (error)
4413 goto out_remove_devs;
4414 scsi_autopm_put_device(SDp);
4415
4416 sdev_printk(KERN_NOTICE, SDp,
4417 "Attached scsi tape %s\n", tape_name(tpnt));
4418 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4419 tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
4420 queue_dma_alignment(SDp->request_queue) + 1);
4421
4422 return 0;
4423
4424out_remove_devs:
4425 remove_cdevs(tpnt);
4426 kfree(tpnt->stats);
4427out_idr_remove:
4428 spin_lock(&st_index_lock);
4429 idr_remove(&st_index_idr, tpnt->index);
4430 spin_unlock(&st_index_lock);
4431out_put_queue:
4432 blk_put_queue(disk->queue);
4433out_put_disk:
4434 put_disk(disk);
4435 kfree(tpnt);
4436out_buffer_free:
4437 kfree(buffer);
4438out:
4439 scsi_autopm_put_device(SDp);
4440 return -ENODEV;
4441};
4442
4443
4444static int st_remove(struct device *dev)
4445{
4446 struct scsi_tape *tpnt = dev_get_drvdata(dev);
4447 int index = tpnt->index;
4448
4449 scsi_autopm_get_device(to_scsi_device(dev));
4450 remove_cdevs(tpnt);
4451
4452 mutex_lock(&st_ref_mutex);
4453 kref_put(&tpnt->kref, scsi_tape_release);
4454 mutex_unlock(&st_ref_mutex);
4455 spin_lock(&st_index_lock);
4456 idr_remove(&st_index_idr, index);
4457 spin_unlock(&st_index_lock);
4458 return 0;
4459}
4460
4461/**
4462 * scsi_tape_release - Called to free the Scsi_Tape structure
4463 * @kref: pointer to embedded kref
4464 *
4465 * st_ref_mutex must be held entering this routine. Because it is
4466 * called on last put, you should always use the scsi_tape_get()
4467 * scsi_tape_put() helpers which manipulate the semaphore directly
4468 * and never do a direct kref_put().
4469 **/
4470static void scsi_tape_release(struct kref *kref)
4471{
4472 struct scsi_tape *tpnt = to_scsi_tape(kref);
4473 struct gendisk *disk = tpnt->disk;
4474
4475 tpnt->device = NULL;
4476
4477 if (tpnt->buffer) {
4478 normalize_buffer(tpnt->buffer);
4479 kfree(tpnt->buffer->reserved_pages);
4480 kfree(tpnt->buffer);
4481 }
4482
4483 disk->private_data = NULL;
4484 put_disk(disk);
4485 kfree(tpnt->stats);
4486 kfree(tpnt);
4487 return;
4488}
4489
4490static struct class st_sysfs_class = {
4491 .name = "scsi_tape",
4492 .dev_groups = st_dev_groups,
4493};
4494
4495static int __init init_st(void)
4496{
4497 int err;
4498
4499 validate_options();
4500
4501 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4502 verstr, st_fixed_buffer_size, st_max_sg_segs);
4503
4504 debugging = (debug_flag > 0) ? debug_flag : NO_DEBUG;
4505 if (debugging) {
4506 printk(KERN_INFO "st: Debugging enabled debug_flag = %d\n",
4507 debugging);
4508 }
4509
4510 err = class_register(&st_sysfs_class);
4511 if (err) {
4512 pr_err("Unable register sysfs class for SCSI tapes\n");
4513 return err;
4514 }
4515
4516 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4517 ST_MAX_TAPE_ENTRIES, "st");
4518 if (err) {
4519 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4520 SCSI_TAPE_MAJOR);
4521 goto err_class;
4522 }
4523
4524 err = scsi_register_driver(&st_template.gendrv);
4525 if (err)
4526 goto err_chrdev;
4527
4528 return 0;
4529
4530err_chrdev:
4531 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4532 ST_MAX_TAPE_ENTRIES);
4533err_class:
4534 class_unregister(&st_sysfs_class);
4535 return err;
4536}
4537
4538static void __exit exit_st(void)
4539{
4540 scsi_unregister_driver(&st_template.gendrv);
4541 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4542 ST_MAX_TAPE_ENTRIES);
4543 class_unregister(&st_sysfs_class);
4544 idr_destroy(&st_index_idr);
4545 printk(KERN_INFO "st: Unloaded.\n");
4546}
4547
4548module_init(init_st);
4549module_exit(exit_st);
4550
4551
4552/* The sysfs driver interface. Read-only at the moment */
4553static ssize_t try_direct_io_show(struct device_driver *ddp, char *buf)
4554{
4555 return scnprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4556}
4557static DRIVER_ATTR_RO(try_direct_io);
4558
4559static ssize_t fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4560{
4561 return scnprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4562}
4563static DRIVER_ATTR_RO(fixed_buffer_size);
4564
4565static ssize_t max_sg_segs_show(struct device_driver *ddp, char *buf)
4566{
4567 return scnprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4568}
4569static DRIVER_ATTR_RO(max_sg_segs);
4570
4571static ssize_t version_show(struct device_driver *ddd, char *buf)
4572{
4573 return scnprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4574}
4575static DRIVER_ATTR_RO(version);
4576
4577#if DEBUG
4578static ssize_t debug_flag_store(struct device_driver *ddp,
4579 const char *buf, size_t count)
4580{
4581/* We only care what the first byte of the data is the rest is unused.
4582 * if it's a '1' we turn on debug and if it's a '0' we disable it. All
4583 * other values have -EINVAL returned if they are passed in.
4584 */
4585 if (count > 0) {
4586 if (buf[0] == '0') {
4587 debugging = NO_DEBUG;
4588 return count;
4589 } else if (buf[0] == '1') {
4590 debugging = 1;
4591 return count;
4592 }
4593 }
4594 return -EINVAL;
4595}
4596
4597static ssize_t debug_flag_show(struct device_driver *ddp, char *buf)
4598{
4599 return scnprintf(buf, PAGE_SIZE, "%d\n", debugging);
4600}
4601static DRIVER_ATTR_RW(debug_flag);
4602#endif
4603
4604static struct attribute *st_drv_attrs[] = {
4605 &driver_attr_try_direct_io.attr,
4606 &driver_attr_fixed_buffer_size.attr,
4607 &driver_attr_max_sg_segs.attr,
4608 &driver_attr_version.attr,
4609#if DEBUG
4610 &driver_attr_debug_flag.attr,
4611#endif
4612 NULL,
4613};
4614ATTRIBUTE_GROUPS(st_drv);
4615
4616/* The sysfs simple class interface */
4617static ssize_t
4618defined_show(struct device *dev, struct device_attribute *attr, char *buf)
4619{
4620 struct st_modedef *STm = dev_get_drvdata(dev);
4621 ssize_t l = 0;
4622
4623 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4624 return l;
4625}
4626static DEVICE_ATTR_RO(defined);
4627
4628static ssize_t
4629default_blksize_show(struct device *dev, struct device_attribute *attr,
4630 char *buf)
4631{
4632 struct st_modedef *STm = dev_get_drvdata(dev);
4633 ssize_t l = 0;
4634
4635 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4636 return l;
4637}
4638static DEVICE_ATTR_RO(default_blksize);
4639
4640static ssize_t
4641default_density_show(struct device *dev, struct device_attribute *attr,
4642 char *buf)
4643{
4644 struct st_modedef *STm = dev_get_drvdata(dev);
4645 ssize_t l = 0;
4646 char *fmt;
4647
4648 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4649 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4650 return l;
4651}
4652static DEVICE_ATTR_RO(default_density);
4653
4654static ssize_t
4655default_compression_show(struct device *dev, struct device_attribute *attr,
4656 char *buf)
4657{
4658 struct st_modedef *STm = dev_get_drvdata(dev);
4659 ssize_t l = 0;
4660
4661 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4662 return l;
4663}
4664static DEVICE_ATTR_RO(default_compression);
4665
4666static ssize_t
4667options_show(struct device *dev, struct device_attribute *attr, char *buf)
4668{
4669 struct st_modedef *STm = dev_get_drvdata(dev);
4670 struct scsi_tape *STp = STm->tape;
4671 int options;
4672 ssize_t l = 0;
4673
4674 options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
4675 options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
4676 options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
4677 DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
4678 options |= STp->two_fm ? MT_ST_TWO_FM : 0;
4679 options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
4680 options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
4681 options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
4682 options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
4683 options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
4684 options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
4685 options |= STm->sysv ? MT_ST_SYSV : 0;
4686 options |= STp->immediate ? MT_ST_NOWAIT : 0;
4687 options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0;
4688 options |= STp->sili ? MT_ST_SILI : 0;
4689
4690 l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
4691 return l;
4692}
4693static DEVICE_ATTR_RO(options);
4694
4695/* Support for tape stats */
4696
4697/**
4698 * read_cnt_show - return read count - count of reads made from tape drive
4699 * @dev: struct device
4700 * @attr: attribute structure
4701 * @buf: buffer to return formatted data in
4702 */
4703static ssize_t read_cnt_show(struct device *dev,
4704 struct device_attribute *attr, char *buf)
4705{
4706 struct st_modedef *STm = dev_get_drvdata(dev);
4707
4708 return sprintf(buf, "%lld",
4709 (long long)atomic64_read(&STm->tape->stats->read_cnt));
4710}
4711static DEVICE_ATTR_RO(read_cnt);
4712
4713/**
4714 * read_byte_cnt_show - return read byte count - tape drives
4715 * may use blocks less than 512 bytes this gives the raw byte count of
4716 * of data read from the tape drive.
4717 * @dev: struct device
4718 * @attr: attribute structure
4719 * @buf: buffer to return formatted data in
4720 */
4721static ssize_t read_byte_cnt_show(struct device *dev,
4722 struct device_attribute *attr, char *buf)
4723{
4724 struct st_modedef *STm = dev_get_drvdata(dev);
4725
4726 return sprintf(buf, "%lld",
4727 (long long)atomic64_read(&STm->tape->stats->read_byte_cnt));
4728}
4729static DEVICE_ATTR_RO(read_byte_cnt);
4730
4731/**
4732 * read_ns_show - return read ns - overall time spent waiting on reads in ns.
4733 * @dev: struct device
4734 * @attr: attribute structure
4735 * @buf: buffer to return formatted data in
4736 */
4737static ssize_t read_ns_show(struct device *dev,
4738 struct device_attribute *attr, char *buf)
4739{
4740 struct st_modedef *STm = dev_get_drvdata(dev);
4741
4742 return sprintf(buf, "%lld",
4743 (long long)atomic64_read(&STm->tape->stats->tot_read_time));
4744}
4745static DEVICE_ATTR_RO(read_ns);
4746
4747/**
4748 * write_cnt_show - write count - number of user calls
4749 * to write(2) that have written data to tape.
4750 * @dev: struct device
4751 * @attr: attribute structure
4752 * @buf: buffer to return formatted data in
4753 */
4754static ssize_t write_cnt_show(struct device *dev,
4755 struct device_attribute *attr, char *buf)
4756{
4757 struct st_modedef *STm = dev_get_drvdata(dev);
4758
4759 return sprintf(buf, "%lld",
4760 (long long)atomic64_read(&STm->tape->stats->write_cnt));
4761}
4762static DEVICE_ATTR_RO(write_cnt);
4763
4764/**
4765 * write_byte_cnt_show - write byte count - raw count of
4766 * bytes written to tape.
4767 * @dev: struct device
4768 * @attr: attribute structure
4769 * @buf: buffer to return formatted data in
4770 */
4771static ssize_t write_byte_cnt_show(struct device *dev,
4772 struct device_attribute *attr, char *buf)
4773{
4774 struct st_modedef *STm = dev_get_drvdata(dev);
4775
4776 return sprintf(buf, "%lld",
4777 (long long)atomic64_read(&STm->tape->stats->write_byte_cnt));
4778}
4779static DEVICE_ATTR_RO(write_byte_cnt);
4780
4781/**
4782 * write_ns_show - write ns - number of nanoseconds waiting on write
4783 * requests to complete.
4784 * @dev: struct device
4785 * @attr: attribute structure
4786 * @buf: buffer to return formatted data in
4787 */
4788static ssize_t write_ns_show(struct device *dev,
4789 struct device_attribute *attr, char *buf)
4790{
4791 struct st_modedef *STm = dev_get_drvdata(dev);
4792
4793 return sprintf(buf, "%lld",
4794 (long long)atomic64_read(&STm->tape->stats->tot_write_time));
4795}
4796static DEVICE_ATTR_RO(write_ns);
4797
4798/**
4799 * in_flight_show - number of I/Os currently in flight -
4800 * in most cases this will be either 0 or 1. It may be higher if someone
4801 * has also issued other SCSI commands such as via an ioctl.
4802 * @dev: struct device
4803 * @attr: attribute structure
4804 * @buf: buffer to return formatted data in
4805 */
4806static ssize_t in_flight_show(struct device *dev,
4807 struct device_attribute *attr, char *buf)
4808{
4809 struct st_modedef *STm = dev_get_drvdata(dev);
4810
4811 return sprintf(buf, "%lld",
4812 (long long)atomic64_read(&STm->tape->stats->in_flight));
4813}
4814static DEVICE_ATTR_RO(in_flight);
4815
4816/**
4817 * io_ns_show - io wait ns - this is the number of ns spent
4818 * waiting on all I/O to complete. This includes tape movement commands
4819 * such as rewinding, seeking to end of file or tape, it also includes
4820 * read and write. To determine the time spent on tape movement
4821 * subtract the read and write ns from this value.
4822 * @dev: struct device
4823 * @attr: attribute structure
4824 * @buf: buffer to return formatted data in
4825 */
4826static ssize_t io_ns_show(struct device *dev,
4827 struct device_attribute *attr, char *buf)
4828{
4829 struct st_modedef *STm = dev_get_drvdata(dev);
4830
4831 return sprintf(buf, "%lld",
4832 (long long)atomic64_read(&STm->tape->stats->tot_io_time));
4833}
4834static DEVICE_ATTR_RO(io_ns);
4835
4836/**
4837 * other_cnt_show - other io count - this is the number of
4838 * I/O requests other than read and write requests.
4839 * Typically these are tape movement requests but will include driver
4840 * tape movement. This includes only requests issued by the st driver.
4841 * @dev: struct device
4842 * @attr: attribute structure
4843 * @buf: buffer to return formatted data in
4844 */
4845static ssize_t other_cnt_show(struct device *dev,
4846 struct device_attribute *attr, char *buf)
4847{
4848 struct st_modedef *STm = dev_get_drvdata(dev);
4849
4850 return sprintf(buf, "%lld",
4851 (long long)atomic64_read(&STm->tape->stats->other_cnt));
4852}
4853static DEVICE_ATTR_RO(other_cnt);
4854
4855/**
4856 * resid_cnt_show - A count of the number of times we get a residual
4857 * count - this should indicate someone issuing reads larger than the
4858 * block size on tape.
4859 * @dev: struct device
4860 * @attr: attribute structure
4861 * @buf: buffer to return formatted data in
4862 */
4863static ssize_t resid_cnt_show(struct device *dev,
4864 struct device_attribute *attr, char *buf)
4865{
4866 struct st_modedef *STm = dev_get_drvdata(dev);
4867
4868 return sprintf(buf, "%lld",
4869 (long long)atomic64_read(&STm->tape->stats->resid_cnt));
4870}
4871static DEVICE_ATTR_RO(resid_cnt);
4872
4873static struct attribute *st_dev_attrs[] = {
4874 &dev_attr_defined.attr,
4875 &dev_attr_default_blksize.attr,
4876 &dev_attr_default_density.attr,
4877 &dev_attr_default_compression.attr,
4878 &dev_attr_options.attr,
4879 NULL,
4880};
4881
4882static struct attribute *st_stats_attrs[] = {
4883 &dev_attr_read_cnt.attr,
4884 &dev_attr_read_byte_cnt.attr,
4885 &dev_attr_read_ns.attr,
4886 &dev_attr_write_cnt.attr,
4887 &dev_attr_write_byte_cnt.attr,
4888 &dev_attr_write_ns.attr,
4889 &dev_attr_in_flight.attr,
4890 &dev_attr_io_ns.attr,
4891 &dev_attr_other_cnt.attr,
4892 &dev_attr_resid_cnt.attr,
4893 NULL,
4894};
4895
4896static struct attribute_group stats_group = {
4897 .name = "stats",
4898 .attrs = st_stats_attrs,
4899};
4900
4901static struct attribute_group st_group = {
4902 .attrs = st_dev_attrs,
4903};
4904
4905static const struct attribute_group *st_dev_groups[] = {
4906 &st_group,
4907 &stats_group,
4908 NULL,
4909};
4910
4911/* The following functions may be useful for a larger audience. */
4912static int sgl_map_user_pages(struct st_buffer *STbp,
4913 const unsigned int max_pages, unsigned long uaddr,
4914 size_t count, int rw)
4915{
4916 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4917 unsigned long start = uaddr >> PAGE_SHIFT;
4918 const int nr_pages = end - start;
4919 int res, i;
4920 struct page **pages;
4921 struct rq_map_data *mdata = &STbp->map_data;
4922
4923 /* User attempted Overflow! */
4924 if ((uaddr + count) < uaddr)
4925 return -EINVAL;
4926
4927 /* Too big */
4928 if (nr_pages > max_pages)
4929 return -ENOMEM;
4930
4931 /* Hmm? */
4932 if (count == 0)
4933 return 0;
4934
4935 pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
4936 if (pages == NULL)
4937 return -ENOMEM;
4938
4939 /* Try to fault in all of the necessary pages */
4940 /* rw==READ means read from drive, write into memory area */
4941 res = pin_user_pages_fast(uaddr, nr_pages, rw == READ ? FOLL_WRITE : 0,
4942 pages);
4943
4944 /* Errors and no page mapped should return here */
4945 if (res < nr_pages)
4946 goto out_unmap;
4947
4948 for (i=0; i < nr_pages; i++) {
4949 /* FIXME: flush superflous for rw==READ,
4950 * probably wrong function for rw==WRITE
4951 */
4952 flush_dcache_page(pages[i]);
4953 }
4954
4955 mdata->offset = uaddr & ~PAGE_MASK;
4956 STbp->mapped_pages = pages;
4957
4958 return nr_pages;
4959 out_unmap:
4960 if (res > 0) {
4961 unpin_user_pages(pages, res);
4962 res = 0;
4963 }
4964 kfree(pages);
4965 return res;
4966}
4967
4968
4969/* And unmap them... */
4970static int sgl_unmap_user_pages(struct st_buffer *STbp,
4971 const unsigned int nr_pages, int dirtied)
4972{
4973 /* FIXME: cache flush missing for rw==READ */
4974 unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);
4975
4976 kfree(STbp->mapped_pages);
4977 STbp->mapped_pages = NULL;
4978
4979 return 0;
4980}