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v3.1
 
   1/*
   2 *  History:
   3 *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4 *           to allow user process control of SCSI devices.
   5 *  Development Sponsored by Killy Corp. NY NY
   6 *
   7 * Original driver (sg.c):
   8 *        Copyright (C) 1992 Lawrence Foard
   9 * Version 2 and 3 extensions to driver:
  10 *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11 *
  12 *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13 *
  14 * This program is free software; you can redistribute it and/or modify
  15 * it under the terms of the GNU General Public License as published by
  16 * the Free Software Foundation; either version 2, or (at your option)
  17 * any later version.
  18 *
  19 */
  20
  21static int sg_version_num = 30534;	/* 2 digits for each component */
  22#define SG_VERSION_STR "3.5.34"
  23
  24/*
  25 *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26 *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27 *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28 *        (otherwise the macros compile to empty statements).
  29 *
  30 */
  31#include <linux/module.h>
  32
  33#include <linux/fs.h>
  34#include <linux/kernel.h>
  35#include <linux/sched.h>
  36#include <linux/string.h>
  37#include <linux/mm.h>
  38#include <linux/errno.h>
  39#include <linux/mtio.h>
  40#include <linux/ioctl.h>
  41#include <linux/slab.h>
  42#include <linux/fcntl.h>
  43#include <linux/init.h>
  44#include <linux/poll.h>
  45#include <linux/moduleparam.h>
  46#include <linux/cdev.h>
  47#include <linux/idr.h>
  48#include <linux/seq_file.h>
  49#include <linux/blkdev.h>
  50#include <linux/delay.h>
  51#include <linux/blktrace_api.h>
  52#include <linux/mutex.h>
 
 
 
 
  53
  54#include "scsi.h"
  55#include <scsi/scsi_dbg.h>
  56#include <scsi/scsi_host.h>
  57#include <scsi/scsi_driver.h>
  58#include <scsi/scsi_ioctl.h>
  59#include <scsi/sg.h>
  60
  61#include "scsi_logging.h"
  62
  63#ifdef CONFIG_SCSI_PROC_FS
  64#include <linux/proc_fs.h>
  65static char *sg_version_date = "20061027";
  66
  67static int sg_proc_init(void);
  68static void sg_proc_cleanup(void);
  69#endif
  70
  71#define SG_ALLOW_DIO_DEF 0
  72
  73#define SG_MAX_DEVS 32768
  74
  75/*
  76 * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  77 * Then when using 32 bit integers x * m may overflow during the calculation.
  78 * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  79 * calculates the same, but prevents the overflow when both m and d
  80 * are "small" numbers (like HZ and USER_HZ).
  81 * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  82 * in 32 bits.
  83 */
  84#define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  85
  86#define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  87
  88int sg_big_buff = SG_DEF_RESERVED_SIZE;
  89/* N.B. This variable is readable and writeable via
  90   /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  91   of this size (or less if there is not enough memory) will be reserved
  92   for use by this file descriptor. [Deprecated usage: this variable is also
  93   readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  94   the kernel (i.e. it is not a module).] */
  95static int def_reserved_size = -1;	/* picks up init parameter */
  96static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  97
  98static int scatter_elem_sz = SG_SCATTER_SZ;
  99static int scatter_elem_sz_prev = SG_SCATTER_SZ;
 100
 101#define SG_SECTOR_SZ 512
 102
 103static int sg_add(struct device *, struct class_interface *);
 104static void sg_remove(struct device *, struct class_interface *);
 105
 106static DEFINE_MUTEX(sg_mutex);
 107
 108static DEFINE_IDR(sg_index_idr);
 109static DEFINE_RWLOCK(sg_index_lock);	/* Also used to lock
 110							   file descriptor list for device */
 111
 112static struct class_interface sg_interface = {
 113	.add_dev	= sg_add,
 114	.remove_dev	= sg_remove,
 115};
 116
 117typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 118	unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 119	unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 120	unsigned bufflen;	/* Size of (aggregate) data buffer */
 121	struct page **pages;
 122	int page_order;
 123	char dio_in_use;	/* 0->indirect IO (or mmap), 1->dio */
 124	unsigned char cmd_opcode; /* first byte of command */
 125} Sg_scatter_hold;
 126
 127struct sg_device;		/* forward declarations */
 128struct sg_fd;
 129
 130typedef struct sg_request {	/* SG_MAX_QUEUE requests outstanding per file */
 131	struct sg_request *nextrp;	/* NULL -> tail request (slist) */
 132	struct sg_fd *parentfp;	/* NULL -> not in use */
 133	Sg_scatter_hold data;	/* hold buffer, perhaps scatter list */
 134	sg_io_hdr_t header;	/* scsi command+info, see <scsi/sg.h> */
 135	unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 136	char res_used;		/* 1 -> using reserve buffer, 0 -> not ... */
 137	char orphan;		/* 1 -> drop on sight, 0 -> normal */
 138	char sg_io_owned;	/* 1 -> packet belongs to SG_IO */
 139	volatile char done;	/* 0->before bh, 1->before read, 2->read */
 
 140	struct request *rq;
 141	struct bio *bio;
 142	struct execute_work ew;
 143} Sg_request;
 144
 145typedef struct sg_fd {		/* holds the state of a file descriptor */
 146	struct list_head sfd_siblings;
 147	struct sg_device *parentdp;	/* owning device */
 148	wait_queue_head_t read_wait;	/* queue read until command done */
 149	rwlock_t rq_list_lock;	/* protect access to list in req_arr */
 
 150	int timeout;		/* defaults to SG_DEFAULT_TIMEOUT      */
 151	int timeout_user;	/* defaults to SG_DEFAULT_TIMEOUT_USER */
 152	Sg_scatter_hold reserve;	/* buffer held for this file descriptor */
 153	unsigned save_scat_len;	/* original length of trunc. scat. element */
 154	Sg_request *headrp;	/* head of request slist, NULL->empty */
 155	struct fasync_struct *async_qp;	/* used by asynchronous notification */
 156	Sg_request req_arr[SG_MAX_QUEUE];	/* used as singly-linked list */
 157	char low_dma;		/* as in parent but possibly overridden to 1 */
 158	char force_packid;	/* 1 -> pack_id input to read(), 0 -> ignored */
 159	volatile char closed;	/* 1 -> fd closed but request(s) outstanding */
 160	char cmd_q;		/* 1 -> allow command queuing, 0 -> don't */
 161	char next_cmd_len;	/* 0 -> automatic (def), >0 -> use on next write() */
 162	char keep_orphan;	/* 0 -> drop orphan (def), 1 -> keep for read() */
 163	char mmap_called;	/* 0 -> mmap() never called on this fd */
 
 164	struct kref f_ref;
 165	struct execute_work ew;
 166} Sg_fd;
 167
 168typedef struct sg_device { /* holds the state of each scsi generic device */
 169	struct scsi_device *device;
 170	wait_queue_head_t o_excl_wait;	/* queue open() when O_EXCL in use */
 
 171	int sg_tablesize;	/* adapter's max scatter-gather table size */
 172	u32 index;		/* device index number */
 173	struct list_head sfds;
 174	volatile char detached;	/* 0->attached, 1->detached pending removal */
 175	volatile char exclude;	/* opened for exclusive access */
 
 
 176	char sgdebug;		/* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 177	struct gendisk *disk;
 178	struct cdev * cdev;	/* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 179	struct kref d_ref;
 180} Sg_device;
 181
 182/* tasklet or soft irq callback */
 183static void sg_rq_end_io(struct request *rq, int uptodate);
 184static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 185static int sg_finish_rem_req(Sg_request * srp);
 186static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 187static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 188			   Sg_request * srp);
 189static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 190			const char __user *buf, size_t count, int blocking,
 191			int read_only, int sg_io_owned, Sg_request **o_srp);
 192static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 193			   unsigned char *cmnd, int timeout, int blocking);
 194static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 195static void sg_remove_scat(Sg_scatter_hold * schp);
 196static void sg_build_reserve(Sg_fd * sfp, int req_size);
 197static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 198static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 199static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 200static void sg_remove_sfp(struct kref *);
 201static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 202static Sg_request *sg_add_request(Sg_fd * sfp);
 203static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 204static int sg_res_in_use(Sg_fd * sfp);
 205static Sg_device *sg_get_dev(int dev);
 206static void sg_put_dev(Sg_device *sdp);
 207
 208#define SZ_SG_HEADER sizeof(struct sg_header)
 209#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 210#define SZ_SG_IOVEC sizeof(sg_iovec_t)
 211#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 212
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 213static int sg_allow_access(struct file *filp, unsigned char *cmd)
 214{
 215	struct sg_fd *sfp = filp->private_data;
 216
 217	if (sfp->parentdp->device->type == TYPE_SCANNER)
 218		return 0;
 219
 220	return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
 221}
 222
 223static int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 224sg_open(struct inode *inode, struct file *filp)
 225{
 226	int dev = iminor(inode);
 227	int flags = filp->f_flags;
 228	struct request_queue *q;
 229	Sg_device *sdp;
 230	Sg_fd *sfp;
 231	int res;
 232	int retval;
 233
 234	mutex_lock(&sg_mutex);
 235	nonseekable_open(inode, filp);
 236	SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 
 237	sdp = sg_get_dev(dev);
 238	if (IS_ERR(sdp)) {
 239		retval = PTR_ERR(sdp);
 240		sdp = NULL;
 241		goto sg_put;
 242	}
 243
 244	/* This driver's module count bumped by fops_get in <linux/fs.h> */
 245	/* Prevent the device driver from vanishing while we sleep */
 246	retval = scsi_device_get(sdp->device);
 247	if (retval)
 248		goto sg_put;
 249
 250	retval = scsi_autopm_get_device(sdp->device);
 251	if (retval)
 252		goto sdp_put;
 253
 
 
 
 254	if (!((flags & O_NONBLOCK) ||
 255	      scsi_block_when_processing_errors(sdp->device))) {
 256		retval = -ENXIO;
 257		/* we are in error recovery for this device */
 258		goto error_out;
 259	}
 260
 261	if (flags & O_EXCL) {
 262		if (O_RDONLY == (flags & O_ACCMODE)) {
 263			retval = -EPERM; /* Can't lock it with read only access */
 264			goto error_out;
 265		}
 266		if (!list_empty(&sdp->sfds) && (flags & O_NONBLOCK)) {
 267			retval = -EBUSY;
 268			goto error_out;
 269		}
 270		res = 0;
 271		__wait_event_interruptible(sdp->o_excl_wait,
 272					   ((!list_empty(&sdp->sfds) || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 273		if (res) {
 274			retval = res;	/* -ERESTARTSYS because signal hit process */
 275			goto error_out;
 276		}
 277	} else if (sdp->exclude) {	/* some other fd has an exclusive lock on dev */
 278		if (flags & O_NONBLOCK) {
 279			retval = -EBUSY;
 280			goto error_out;
 281		}
 282		res = 0;
 283		__wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 284					   res);
 285		if (res) {
 286			retval = res;	/* -ERESTARTSYS because signal hit process */
 287			goto error_out;
 288		}
 
 
 
 
 289	}
 290	if (sdp->detached) {
 291		retval = -ENODEV;
 292		goto error_out;
 293	}
 294	if (list_empty(&sdp->sfds)) {	/* no existing opens on this device */
 
 295		sdp->sgdebug = 0;
 296		q = sdp->device->request_queue;
 297		sdp->sg_tablesize = queue_max_segments(q);
 298	}
 299	if ((sfp = sg_add_sfp(sdp, dev)))
 300		filp->private_data = sfp;
 301	else {
 302		if (flags & O_EXCL) {
 303			sdp->exclude = 0;	/* undo if error */
 304			wake_up_interruptible(&sdp->o_excl_wait);
 305		}
 306		retval = -ENOMEM;
 307		goto error_out;
 308	}
 
 
 
 
 
 309	retval = 0;
 310error_out:
 311	if (retval) {
 312		scsi_autopm_put_device(sdp->device);
 313sdp_put:
 314		scsi_device_put(sdp->device);
 315	}
 316sg_put:
 317	if (sdp)
 318		sg_put_dev(sdp);
 319	mutex_unlock(&sg_mutex);
 320	return retval;
 
 
 
 
 
 
 
 
 
 
 
 
 
 321}
 322
 323/* Following function was formerly called 'sg_close' */
 
 324static int
 325sg_release(struct inode *inode, struct file *filp)
 326{
 327	Sg_device *sdp;
 328	Sg_fd *sfp;
 329
 330	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 331		return -ENXIO;
 332	SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 333
 334	sfp->closed = 1;
 335
 336	sdp->exclude = 0;
 337	wake_up_interruptible(&sdp->o_excl_wait);
 338
 
 339	scsi_autopm_put_device(sdp->device);
 340	kref_put(&sfp->f_ref, sg_remove_sfp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 341	return 0;
 342}
 343
 344static ssize_t
 345sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 346{
 347	Sg_device *sdp;
 348	Sg_fd *sfp;
 349	Sg_request *srp;
 350	int req_pack_id = -1;
 351	sg_io_hdr_t *hp;
 352	struct sg_header *old_hdr = NULL;
 353	int retval = 0;
 
 
 
 
 
 
 
 
 354
 355	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 356		return -ENXIO;
 357	SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 358				   sdp->disk->disk_name, (int) count));
 
 
 
 
 
 359
 360	if (!access_ok(VERIFY_WRITE, buf, count))
 361		return -EFAULT;
 362	if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 363		old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 364		if (!old_hdr)
 365			return -ENOMEM;
 366		if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 367			retval = -EFAULT;
 368			goto free_old_hdr;
 369		}
 370		if (old_hdr->reply_len < 0) {
 371			if (count >= SZ_SG_IO_HDR) {
 372				sg_io_hdr_t *new_hdr;
 373				new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 374				if (!new_hdr) {
 375					retval = -ENOMEM;
 376					goto free_old_hdr;
 377				}
 378				retval =__copy_from_user
 379				    (new_hdr, buf, SZ_SG_IO_HDR);
 380				req_pack_id = new_hdr->pack_id;
 381				kfree(new_hdr);
 382				if (retval) {
 383					retval = -EFAULT;
 384					goto free_old_hdr;
 385				}
 386			}
 387		} else
 388			req_pack_id = old_hdr->pack_id;
 389	}
 390	srp = sg_get_rq_mark(sfp, req_pack_id);
 391	if (!srp) {		/* now wait on packet to arrive */
 392		if (sdp->detached) {
 393			retval = -ENODEV;
 394			goto free_old_hdr;
 395		}
 396		if (filp->f_flags & O_NONBLOCK) {
 397			retval = -EAGAIN;
 398			goto free_old_hdr;
 399		}
 400		while (1) {
 401			retval = 0; /* following macro beats race condition */
 402			__wait_event_interruptible(sfp->read_wait,
 403				(sdp->detached ||
 404				(srp = sg_get_rq_mark(sfp, req_pack_id))), 
 405				retval);
 406			if (sdp->detached) {
 407				retval = -ENODEV;
 408				goto free_old_hdr;
 409			}
 410			if (0 == retval)
 411				break;
 412
 413			/* -ERESTARTSYS as signal hit process */
 414			goto free_old_hdr;
 415		}
 416	}
 417	if (srp->header.interface_id != '\0') {
 418		retval = sg_new_read(sfp, buf, count, srp);
 419		goto free_old_hdr;
 420	}
 
 
 421
 422	hp = &srp->header;
 423	if (old_hdr == NULL) {
 424		old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 425		if (! old_hdr) {
 426			retval = -ENOMEM;
 427			goto free_old_hdr;
 428		}
 429	}
 430	memset(old_hdr, 0, SZ_SG_HEADER);
 431	old_hdr->reply_len = (int) hp->timeout;
 432	old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 433	old_hdr->pack_id = hp->pack_id;
 434	old_hdr->twelve_byte =
 435	    ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 436	old_hdr->target_status = hp->masked_status;
 437	old_hdr->host_status = hp->host_status;
 438	old_hdr->driver_status = hp->driver_status;
 439	if ((CHECK_CONDITION & hp->masked_status) ||
 440	    (DRIVER_SENSE & hp->driver_status))
 441		memcpy(old_hdr->sense_buffer, srp->sense_b,
 442		       sizeof (old_hdr->sense_buffer));
 443	switch (hp->host_status) {
 444	/* This setup of 'result' is for backward compatibility and is best
 445	   ignored by the user who should use target, host + driver status */
 446	case DID_OK:
 447	case DID_PASSTHROUGH:
 448	case DID_SOFT_ERROR:
 449		old_hdr->result = 0;
 450		break;
 451	case DID_NO_CONNECT:
 452	case DID_BUS_BUSY:
 453	case DID_TIME_OUT:
 454		old_hdr->result = EBUSY;
 455		break;
 456	case DID_BAD_TARGET:
 457	case DID_ABORT:
 458	case DID_PARITY:
 459	case DID_RESET:
 460	case DID_BAD_INTR:
 461		old_hdr->result = EIO;
 462		break;
 463	case DID_ERROR:
 464		old_hdr->result = (srp->sense_b[0] == 0 && 
 465				  hp->masked_status == GOOD) ? 0 : EIO;
 466		break;
 467	default:
 468		old_hdr->result = EIO;
 469		break;
 470	}
 471
 472	/* Now copy the result back to the user buffer.  */
 473	if (count >= SZ_SG_HEADER) {
 474		if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 475			retval = -EFAULT;
 476			goto free_old_hdr;
 477		}
 478		buf += SZ_SG_HEADER;
 479		if (count > old_hdr->reply_len)
 480			count = old_hdr->reply_len;
 481		if (count > SZ_SG_HEADER) {
 482			if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 483				retval = -EFAULT;
 484				goto free_old_hdr;
 485			}
 486		}
 487	} else
 488		count = (old_hdr->result == 0) ? 0 : -EIO;
 489	sg_finish_rem_req(srp);
 
 490	retval = count;
 491free_old_hdr:
 492	kfree(old_hdr);
 493	return retval;
 494}
 495
 496static ssize_t
 497sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 498{
 499	sg_io_hdr_t *hp = &srp->header;
 500	int err = 0;
 501	int len;
 502
 503	if (count < SZ_SG_IO_HDR) {
 
 
 
 
 
 504		err = -EINVAL;
 505		goto err_out;
 506	}
 507	hp->sb_len_wr = 0;
 508	if ((hp->mx_sb_len > 0) && hp->sbp) {
 509		if ((CHECK_CONDITION & hp->masked_status) ||
 510		    (DRIVER_SENSE & hp->driver_status)) {
 511			int sb_len = SCSI_SENSE_BUFFERSIZE;
 512			sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 513			len = 8 + (int) srp->sense_b[7];	/* Additional sense length field */
 514			len = (len > sb_len) ? sb_len : len;
 515			if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 516				err = -EFAULT;
 517				goto err_out;
 518			}
 519			hp->sb_len_wr = len;
 520		}
 521	}
 522	if (hp->masked_status || hp->host_status || hp->driver_status)
 523		hp->info |= SG_INFO_CHECK;
 524	if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 525		err = -EFAULT;
 526		goto err_out;
 527	}
 528err_out:
 529	err = sg_finish_rem_req(srp);
 530	return (0 == err) ? count : err;
 
 531}
 532
 533static ssize_t
 534sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 535{
 536	int mxsize, cmd_size, k;
 537	int input_size, blocking;
 538	unsigned char opcode;
 539	Sg_device *sdp;
 540	Sg_fd *sfp;
 541	Sg_request *srp;
 542	struct sg_header old_hdr;
 543	sg_io_hdr_t *hp;
 544	unsigned char cmnd[MAX_COMMAND_SIZE];
 
 
 
 
 
 545
 546	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 547		return -ENXIO;
 548	SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 549				   sdp->disk->disk_name, (int) count));
 550	if (sdp->detached)
 551		return -ENODEV;
 552	if (!((filp->f_flags & O_NONBLOCK) ||
 553	      scsi_block_when_processing_errors(sdp->device)))
 554		return -ENXIO;
 555
 556	if (!access_ok(VERIFY_READ, buf, count))
 557		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 558	if (count < SZ_SG_HEADER)
 559		return -EIO;
 560	if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 561		return -EFAULT;
 562	blocking = !(filp->f_flags & O_NONBLOCK);
 563	if (old_hdr.reply_len < 0)
 564		return sg_new_write(sfp, filp, buf, count,
 565				    blocking, 0, 0, NULL);
 566	if (count < (SZ_SG_HEADER + 6))
 567		return -EIO;	/* The minimum scsi command length is 6 bytes. */
 568
 
 
 
 
 569	if (!(srp = sg_add_request(sfp))) {
 570		SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 
 571		return -EDOM;
 572	}
 573	buf += SZ_SG_HEADER;
 574	__get_user(opcode, buf);
 575	if (sfp->next_cmd_len > 0) {
 576		if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 577			SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 578			sfp->next_cmd_len = 0;
 579			sg_remove_request(sfp, srp);
 580			return -EIO;
 581		}
 582		cmd_size = sfp->next_cmd_len;
 583		sfp->next_cmd_len = 0;	/* reset so only this write() effected */
 584	} else {
 585		cmd_size = COMMAND_SIZE(opcode);	/* based on SCSI command group */
 586		if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 587			cmd_size = 12;
 588	}
 589	SCSI_LOG_TIMEOUT(4, printk(
 
 590		"sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 591/* Determine buffer size.  */
 592	input_size = count - cmd_size;
 593	mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 594	mxsize -= SZ_SG_HEADER;
 595	input_size -= SZ_SG_HEADER;
 596	if (input_size < 0) {
 597		sg_remove_request(sfp, srp);
 598		return -EIO;	/* User did not pass enough bytes for this command. */
 599	}
 600	hp = &srp->header;
 601	hp->interface_id = '\0';	/* indicator of old interface tunnelled */
 602	hp->cmd_len = (unsigned char) cmd_size;
 603	hp->iovec_count = 0;
 604	hp->mx_sb_len = 0;
 605	if (input_size > 0)
 606		hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 607		    SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 608	else
 609		hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 610	hp->dxfer_len = mxsize;
 611	if (hp->dxfer_direction == SG_DXFER_TO_DEV)
 
 612		hp->dxferp = (char __user *)buf + cmd_size;
 613	else
 614		hp->dxferp = NULL;
 615	hp->sbp = NULL;
 616	hp->timeout = old_hdr.reply_len;	/* structure abuse ... */
 617	hp->flags = input_size;	/* structure abuse ... */
 618	hp->pack_id = old_hdr.pack_id;
 619	hp->usr_ptr = NULL;
 620	if (__copy_from_user(cmnd, buf, cmd_size))
 
 621		return -EFAULT;
 
 622	/*
 623	 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 624	 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 625	 * is a non-zero input_size, so emit a warning.
 626	 */
 627	if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 628		static char cmd[TASK_COMM_LEN];
 629		if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 630			printk(KERN_WARNING
 631			       "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 632			       "guessing data in;\n   "
 633			       "program %s not setting count and/or reply_len properly\n",
 634			       old_hdr.reply_len - (int)SZ_SG_HEADER,
 635			       input_size, (unsigned int) cmnd[0],
 636			       current->comm);
 637			strcpy(cmd, current->comm);
 638		}
 639	}
 640	k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 641	return (k < 0) ? k : count;
 642}
 643
 644static ssize_t
 645sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 646		 size_t count, int blocking, int read_only, int sg_io_owned,
 647		 Sg_request **o_srp)
 648{
 649	int k;
 650	Sg_request *srp;
 651	sg_io_hdr_t *hp;
 652	unsigned char cmnd[MAX_COMMAND_SIZE];
 653	int timeout;
 654	unsigned long ul_timeout;
 655
 656	if (count < SZ_SG_IO_HDR)
 657		return -EINVAL;
 658	if (!access_ok(VERIFY_READ, buf, count))
 659		return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 660
 661	sfp->cmd_q = 1;	/* when sg_io_hdr seen, set command queuing on */
 662	if (!(srp = sg_add_request(sfp))) {
 663		SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 
 664		return -EDOM;
 665	}
 666	srp->sg_io_owned = sg_io_owned;
 667	hp = &srp->header;
 668	if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 669		sg_remove_request(sfp, srp);
 670		return -EFAULT;
 671	}
 672	if (hp->interface_id != 'S') {
 673		sg_remove_request(sfp, srp);
 674		return -ENOSYS;
 675	}
 676	if (hp->flags & SG_FLAG_MMAP_IO) {
 677		if (hp->dxfer_len > sfp->reserve.bufflen) {
 678			sg_remove_request(sfp, srp);
 679			return -ENOMEM;	/* MMAP_IO size must fit in reserve buffer */
 680		}
 681		if (hp->flags & SG_FLAG_DIRECT_IO) {
 682			sg_remove_request(sfp, srp);
 683			return -EINVAL;	/* either MMAP_IO or DIRECT_IO (not both) */
 684		}
 685		if (sg_res_in_use(sfp)) {
 686			sg_remove_request(sfp, srp);
 687			return -EBUSY;	/* reserve buffer already being used */
 688		}
 689	}
 690	ul_timeout = msecs_to_jiffies(srp->header.timeout);
 691	timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 692	if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 693		sg_remove_request(sfp, srp);
 694		return -EMSGSIZE;
 695	}
 696	if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 697		sg_remove_request(sfp, srp);
 698		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 699	}
 700	if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 701		sg_remove_request(sfp, srp);
 702		return -EFAULT;
 703	}
 704	if (read_only && sg_allow_access(file, cmnd)) {
 705		sg_remove_request(sfp, srp);
 706		return -EPERM;
 707	}
 708	k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 709	if (k < 0)
 710		return k;
 711	if (o_srp)
 712		*o_srp = srp;
 713	return count;
 714}
 715
 716static int
 717sg_common_write(Sg_fd * sfp, Sg_request * srp,
 718		unsigned char *cmnd, int timeout, int blocking)
 719{
 720	int k, data_dir;
 721	Sg_device *sdp = sfp->parentdp;
 722	sg_io_hdr_t *hp = &srp->header;
 723
 724	srp->data.cmd_opcode = cmnd[0];	/* hold opcode of command */
 725	hp->status = 0;
 726	hp->masked_status = 0;
 727	hp->msg_status = 0;
 728	hp->info = 0;
 729	hp->host_status = 0;
 730	hp->driver_status = 0;
 731	hp->resid = 0;
 732	SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 733			  (int) cmnd[0], (int) hp->cmd_len));
 
 
 
 
 
 
 734
 735	k = sg_start_req(srp, cmnd);
 736	if (k) {
 737		SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 
 738		sg_finish_rem_req(srp);
 
 739		return k;	/* probably out of space --> ENOMEM */
 740	}
 741	if (sdp->detached) {
 742		if (srp->bio)
 743			blk_end_request_all(srp->rq, -EIO);
 
 
 
 
 744		sg_finish_rem_req(srp);
 
 745		return -ENODEV;
 746	}
 747
 748	switch (hp->dxfer_direction) {
 749	case SG_DXFER_TO_FROM_DEV:
 750	case SG_DXFER_FROM_DEV:
 751		data_dir = DMA_FROM_DEVICE;
 752		break;
 753	case SG_DXFER_TO_DEV:
 754		data_dir = DMA_TO_DEVICE;
 755		break;
 756	case SG_DXFER_UNKNOWN:
 757		data_dir = DMA_BIDIRECTIONAL;
 758		break;
 759	default:
 760		data_dir = DMA_NONE;
 761		break;
 762	}
 763	hp->duration = jiffies_to_msecs(jiffies);
 
 
 
 
 
 764
 765	srp->rq->timeout = timeout;
 766	kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
 767	blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 768			      srp->rq, 1, sg_rq_end_io);
 769	return 0;
 770}
 771
 772static int
 773sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 774{
 775	void __user *p = (void __user *)arg;
 776	int __user *ip = p;
 777	int result, val, read_only;
 778	Sg_device *sdp;
 779	Sg_fd *sfp;
 780	Sg_request *srp;
 781	unsigned long iflags;
 782
 783	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 784		return -ENXIO;
 785
 786	SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 787				   sdp->disk->disk_name, (int) cmd_in));
 788	read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 789
 790	switch (cmd_in) {
 791	case SG_IO:
 792		{
 793			int blocking = 1;	/* ignore O_NONBLOCK flag */
 794
 795			if (sdp->detached)
 796				return -ENODEV;
 797			if (!scsi_block_when_processing_errors(sdp->device))
 798				return -ENXIO;
 799			if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 800				return -EFAULT;
 801			result =
 802			    sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 803					 blocking, read_only, 1, &srp);
 804			if (result < 0)
 805				return result;
 806			while (1) {
 807				result = 0;	/* following macro to beat race condition */
 808				__wait_event_interruptible(sfp->read_wait,
 809					(srp->done || sdp->detached),
 810					result);
 811				if (sdp->detached)
 812					return -ENODEV;
 813				write_lock_irq(&sfp->rq_list_lock);
 814				if (srp->done) {
 815					srp->done = 2;
 816					write_unlock_irq(&sfp->rq_list_lock);
 817					break;
 818				}
 819				srp->orphan = 1;
 820				write_unlock_irq(&sfp->rq_list_lock);
 821				return result;	/* -ERESTARTSYS because signal hit process */
 822			}
 823			result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 824			return (result < 0) ? result : 0;
 825		}
 
 
 
 826	case SG_SET_TIMEOUT:
 827		result = get_user(val, ip);
 828		if (result)
 829			return result;
 830		if (val < 0)
 831			return -EIO;
 832		if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 833		    val = MULDIV (INT_MAX, USER_HZ, HZ);
 
 834		sfp->timeout_user = val;
 835		sfp->timeout = MULDIV (val, HZ, USER_HZ);
 836
 837		return 0;
 838	case SG_GET_TIMEOUT:	/* N.B. User receives timeout as return value */
 839				/* strange ..., for backward compatibility */
 840		return sfp->timeout_user;
 841	case SG_SET_FORCE_LOW_DMA:
 842		result = get_user(val, ip);
 843		if (result)
 844			return result;
 845		if (val) {
 846			sfp->low_dma = 1;
 847			if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 848				val = (int) sfp->reserve.bufflen;
 849				sg_remove_scat(&sfp->reserve);
 850				sg_build_reserve(sfp, val);
 851			}
 852		} else {
 853			if (sdp->detached)
 854				return -ENODEV;
 855			sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 856		}
 857		return 0;
 858	case SG_GET_LOW_DMA:
 859		return put_user((int) sfp->low_dma, ip);
 860	case SG_GET_SCSI_ID:
 861		if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 862			return -EFAULT;
 863		else {
 864			sg_scsi_id_t __user *sg_idp = p;
 865
 866			if (sdp->detached)
 867				return -ENODEV;
 868			__put_user((int) sdp->device->host->host_no,
 869				   &sg_idp->host_no);
 870			__put_user((int) sdp->device->channel,
 871				   &sg_idp->channel);
 872			__put_user((int) sdp->device->id, &sg_idp->scsi_id);
 873			__put_user((int) sdp->device->lun, &sg_idp->lun);
 874			__put_user((int) sdp->device->type, &sg_idp->scsi_type);
 875			__put_user((short) sdp->device->host->cmd_per_lun,
 876				   &sg_idp->h_cmd_per_lun);
 877			__put_user((short) sdp->device->queue_depth,
 878				   &sg_idp->d_queue_depth);
 879			__put_user(0, &sg_idp->unused[0]);
 880			__put_user(0, &sg_idp->unused[1]);
 881			return 0;
 882		}
 883	case SG_SET_FORCE_PACK_ID:
 884		result = get_user(val, ip);
 885		if (result)
 886			return result;
 887		sfp->force_packid = val ? 1 : 0;
 888		return 0;
 889	case SG_GET_PACK_ID:
 890		if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 891			return -EFAULT;
 892		read_lock_irqsave(&sfp->rq_list_lock, iflags);
 893		for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 894			if ((1 == srp->done) && (!srp->sg_io_owned)) {
 895				read_unlock_irqrestore(&sfp->rq_list_lock,
 896						       iflags);
 897				__put_user(srp->header.pack_id, ip);
 898				return 0;
 899			}
 900		}
 901		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 902		__put_user(-1, ip);
 903		return 0;
 904	case SG_GET_NUM_WAITING:
 905		read_lock_irqsave(&sfp->rq_list_lock, iflags);
 906		for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 
 907			if ((1 == srp->done) && (!srp->sg_io_owned))
 908				++val;
 909		}
 910		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 911		return put_user(val, ip);
 912	case SG_GET_SG_TABLESIZE:
 913		return put_user(sdp->sg_tablesize, ip);
 914	case SG_SET_RESERVED_SIZE:
 915		result = get_user(val, ip);
 916		if (result)
 917			return result;
 918                if (val < 0)
 919                        return -EINVAL;
 920		val = min_t(int, val,
 921			    queue_max_sectors(sdp->device->request_queue) * 512);
 
 922		if (val != sfp->reserve.bufflen) {
 923			if (sg_res_in_use(sfp) || sfp->mmap_called)
 
 
 924				return -EBUSY;
 925			sg_remove_scat(&sfp->reserve);
 
 
 926			sg_build_reserve(sfp, val);
 927		}
 
 928		return 0;
 929	case SG_GET_RESERVED_SIZE:
 930		val = min_t(int, sfp->reserve.bufflen,
 931			    queue_max_sectors(sdp->device->request_queue) * 512);
 932		return put_user(val, ip);
 933	case SG_SET_COMMAND_Q:
 934		result = get_user(val, ip);
 935		if (result)
 936			return result;
 937		sfp->cmd_q = val ? 1 : 0;
 938		return 0;
 939	case SG_GET_COMMAND_Q:
 940		return put_user((int) sfp->cmd_q, ip);
 941	case SG_SET_KEEP_ORPHAN:
 942		result = get_user(val, ip);
 943		if (result)
 944			return result;
 945		sfp->keep_orphan = val;
 946		return 0;
 947	case SG_GET_KEEP_ORPHAN:
 948		return put_user((int) sfp->keep_orphan, ip);
 949	case SG_NEXT_CMD_LEN:
 950		result = get_user(val, ip);
 951		if (result)
 952			return result;
 
 
 953		sfp->next_cmd_len = (val > 0) ? val : 0;
 954		return 0;
 955	case SG_GET_VERSION_NUM:
 956		return put_user(sg_version_num, ip);
 957	case SG_GET_ACCESS_COUNT:
 958		/* faked - we don't have a real access count anymore */
 959		val = (sdp->device ? 1 : 0);
 960		return put_user(val, ip);
 961	case SG_GET_REQUEST_TABLE:
 962		if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 963			return -EFAULT;
 964		else {
 965			sg_req_info_t *rinfo;
 966			unsigned int ms;
 967
 968			rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 969								GFP_KERNEL);
 970			if (!rinfo)
 971				return -ENOMEM;
 972			read_lock_irqsave(&sfp->rq_list_lock, iflags);
 973			for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 974			     ++val, srp = srp ? srp->nextrp : srp) {
 975				memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 976				if (srp) {
 977					rinfo[val].req_state = srp->done + 1;
 978					rinfo[val].problem =
 979					    srp->header.masked_status & 
 980					    srp->header.host_status & 
 981					    srp->header.driver_status;
 982					if (srp->done)
 983						rinfo[val].duration =
 984							srp->header.duration;
 985					else {
 986						ms = jiffies_to_msecs(jiffies);
 987						rinfo[val].duration =
 988						    (ms > srp->header.duration) ?
 989						    (ms - srp->header.duration) : 0;
 990					}
 991					rinfo[val].orphan = srp->orphan;
 992					rinfo[val].sg_io_owned =
 993							srp->sg_io_owned;
 994					rinfo[val].pack_id =
 995							srp->header.pack_id;
 996					rinfo[val].usr_ptr =
 997							srp->header.usr_ptr;
 998				}
 999			}
1000			read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1001			result = __copy_to_user(p, rinfo, 
1002						SZ_SG_REQ_INFO * SG_MAX_QUEUE);
 
 
 
 
 
1003			result = result ? -EFAULT : 0;
1004			kfree(rinfo);
1005			return result;
1006		}
1007	case SG_EMULATED_HOST:
1008		if (sdp->detached)
1009			return -ENODEV;
1010		return put_user(sdp->device->host->hostt->emulated, ip);
1011	case SG_SCSI_RESET:
1012		if (sdp->detached)
1013			return -ENODEV;
1014		if (filp->f_flags & O_NONBLOCK) {
1015			if (scsi_host_in_recovery(sdp->device->host))
1016				return -EBUSY;
1017		} else if (!scsi_block_when_processing_errors(sdp->device))
1018			return -EBUSY;
1019		result = get_user(val, ip);
1020		if (result)
1021			return result;
1022		if (SG_SCSI_RESET_NOTHING == val)
1023			return 0;
1024		switch (val) {
1025		case SG_SCSI_RESET_DEVICE:
1026			val = SCSI_TRY_RESET_DEVICE;
1027			break;
1028		case SG_SCSI_RESET_TARGET:
1029			val = SCSI_TRY_RESET_TARGET;
1030			break;
1031		case SG_SCSI_RESET_BUS:
1032			val = SCSI_TRY_RESET_BUS;
1033			break;
1034		case SG_SCSI_RESET_HOST:
1035			val = SCSI_TRY_RESET_HOST;
1036			break;
1037		default:
1038			return -EINVAL;
1039		}
1040		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1041			return -EACCES;
1042		return (scsi_reset_provider(sdp->device, val) ==
1043			SUCCESS) ? 0 : -EIO;
1044	case SCSI_IOCTL_SEND_COMMAND:
1045		if (sdp->detached)
1046			return -ENODEV;
1047		if (read_only) {
1048			unsigned char opcode = WRITE_6;
1049			Scsi_Ioctl_Command __user *siocp = p;
1050
1051			if (copy_from_user(&opcode, siocp->data, 1))
1052				return -EFAULT;
1053			if (sg_allow_access(filp, &opcode))
1054				return -EPERM;
1055		}
1056		return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1057	case SG_SET_DEBUG:
1058		result = get_user(val, ip);
1059		if (result)
1060			return result;
1061		sdp->sgdebug = (char) val;
1062		return 0;
1063	case SCSI_IOCTL_GET_IDLUN:
1064	case SCSI_IOCTL_GET_BUS_NUMBER:
1065	case SCSI_IOCTL_PROBE_HOST:
1066	case SG_GET_TRANSFORM:
1067		if (sdp->detached)
1068			return -ENODEV;
1069		return scsi_ioctl(sdp->device, cmd_in, p);
1070	case BLKSECTGET:
1071		return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1072				ip);
1073	case BLKTRACESETUP:
1074		return blk_trace_setup(sdp->device->request_queue,
1075				       sdp->disk->disk_name,
1076				       MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1077				       NULL,
1078				       (char *)arg);
1079	case BLKTRACESTART:
1080		return blk_trace_startstop(sdp->device->request_queue, 1);
1081	case BLKTRACESTOP:
1082		return blk_trace_startstop(sdp->device->request_queue, 0);
1083	case BLKTRACETEARDOWN:
1084		return blk_trace_remove(sdp->device->request_queue);
 
 
 
 
 
 
 
 
1085	default:
1086		if (read_only)
1087			return -EPERM;	/* don't know so take safe approach */
1088		return scsi_ioctl(sdp->device, cmd_in, p);
1089	}
 
 
 
 
 
 
 
1090}
1091
1092static long
1093sg_unlocked_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1094{
 
 
 
1095	int ret;
1096
1097	mutex_lock(&sg_mutex);
1098	ret = sg_ioctl(filp, cmd_in, arg);
1099	mutex_unlock(&sg_mutex);
1100
1101	return ret;
 
 
 
 
1102}
1103
1104#ifdef CONFIG_COMPAT
1105static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1106{
 
1107	Sg_device *sdp;
1108	Sg_fd *sfp;
1109	struct scsi_device *sdev;
1110
1111	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1112		return -ENXIO;
1113
1114	sdev = sdp->device;
1115	if (sdev->host->hostt->compat_ioctl) { 
1116		int ret;
1117
1118		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1119
1120		return ret;
1121	}
1122	
1123	return -ENOIOCTLCMD;
1124}
1125#endif
1126
1127static unsigned int
1128sg_poll(struct file *filp, poll_table * wait)
1129{
1130	unsigned int res = 0;
1131	Sg_device *sdp;
1132	Sg_fd *sfp;
1133	Sg_request *srp;
1134	int count = 0;
1135	unsigned long iflags;
1136
1137	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1138	    || sfp->closed)
1139		return POLLERR;
 
 
 
1140	poll_wait(filp, &sfp->read_wait, wait);
1141	read_lock_irqsave(&sfp->rq_list_lock, iflags);
1142	for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1143		/* if any read waiting, flag it */
1144		if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1145			res = POLLIN | POLLRDNORM;
1146		++count;
1147	}
1148	read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1149
1150	if (sdp->detached)
1151		res |= POLLHUP;
1152	else if (!sfp->cmd_q) {
1153		if (0 == count)
1154			res |= POLLOUT | POLLWRNORM;
1155	} else if (count < SG_MAX_QUEUE)
1156		res |= POLLOUT | POLLWRNORM;
1157	SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1158				   sdp->disk->disk_name, (int) res));
1159	return res;
1160}
1161
1162static int
1163sg_fasync(int fd, struct file *filp, int mode)
1164{
1165	Sg_device *sdp;
1166	Sg_fd *sfp;
1167
1168	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1169		return -ENXIO;
1170	SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1171				   sdp->disk->disk_name, mode));
1172
1173	return fasync_helper(fd, filp, mode, &sfp->async_qp);
1174}
1175
1176static int
1177sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1178{
 
1179	Sg_fd *sfp;
1180	unsigned long offset, len, sa;
1181	Sg_scatter_hold *rsv_schp;
1182	int k, length;
1183
1184	if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1185		return VM_FAULT_SIGBUS;
1186	rsv_schp = &sfp->reserve;
1187	offset = vmf->pgoff << PAGE_SHIFT;
1188	if (offset >= rsv_schp->bufflen)
1189		return VM_FAULT_SIGBUS;
1190	SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1191				   offset, rsv_schp->k_use_sg));
 
1192	sa = vma->vm_start;
1193	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1194	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1195		len = vma->vm_end - sa;
1196		len = (len < length) ? len : length;
1197		if (offset < len) {
1198			struct page *page = nth_page(rsv_schp->pages[k],
1199						     offset >> PAGE_SHIFT);
1200			get_page(page);	/* increment page count */
1201			vmf->page = page;
1202			return 0; /* success */
1203		}
1204		sa += len;
1205		offset -= len;
1206	}
1207
1208	return VM_FAULT_SIGBUS;
1209}
1210
1211static const struct vm_operations_struct sg_mmap_vm_ops = {
1212	.fault = sg_vma_fault,
1213};
1214
1215static int
1216sg_mmap(struct file *filp, struct vm_area_struct *vma)
1217{
1218	Sg_fd *sfp;
1219	unsigned long req_sz, len, sa;
1220	Sg_scatter_hold *rsv_schp;
1221	int k, length;
 
1222
1223	if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1224		return -ENXIO;
1225	req_sz = vma->vm_end - vma->vm_start;
1226	SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1227				   (void *) vma->vm_start, (int) req_sz));
 
1228	if (vma->vm_pgoff)
1229		return -EINVAL;	/* want no offset */
1230	rsv_schp = &sfp->reserve;
1231	if (req_sz > rsv_schp->bufflen)
1232		return -ENOMEM;	/* cannot map more than reserved buffer */
 
 
 
1233
1234	sa = vma->vm_start;
1235	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1236	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1237		len = vma->vm_end - sa;
1238		len = (len < length) ? len : length;
1239		sa += len;
1240	}
1241
1242	sfp->mmap_called = 1;
1243	vma->vm_flags |= VM_RESERVED;
1244	vma->vm_private_data = sfp;
1245	vma->vm_ops = &sg_mmap_vm_ops;
1246	return 0;
 
 
1247}
1248
1249static void sg_rq_end_io_usercontext(struct work_struct *work)
 
1250{
1251	struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1252	struct sg_fd *sfp = srp->parentfp;
1253
1254	sg_finish_rem_req(srp);
 
1255	kref_put(&sfp->f_ref, sg_remove_sfp);
1256}
1257
1258/*
1259 * This function is a "bottom half" handler that is called by the mid
1260 * level when a command is completed (or has failed).
1261 */
1262static void sg_rq_end_io(struct request *rq, int uptodate)
 
1263{
1264	struct sg_request *srp = rq->end_io_data;
 
1265	Sg_device *sdp;
1266	Sg_fd *sfp;
1267	unsigned long iflags;
1268	unsigned int ms;
1269	char *sense;
1270	int result, resid, done = 1;
1271
1272	if (WARN_ON(srp->done != 0))
1273		return;
1274
1275	sfp = srp->parentfp;
1276	if (WARN_ON(sfp == NULL))
1277		return;
1278
1279	sdp = sfp->parentdp;
1280	if (unlikely(sdp->detached))
1281		printk(KERN_INFO "sg_rq_end_io: device detached\n");
1282
1283	sense = rq->sense;
1284	result = rq->errors;
1285	resid = rq->resid_len;
1286
1287	SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1288		sdp->disk->disk_name, srp->header.pack_id, result));
 
 
 
 
 
1289	srp->header.resid = resid;
1290	ms = jiffies_to_msecs(jiffies);
1291	srp->header.duration = (ms > srp->header.duration) ?
1292				(ms - srp->header.duration) : 0;
1293	if (0 != result) {
1294		struct scsi_sense_hdr sshdr;
1295
1296		srp->header.status = 0xff & result;
1297		srp->header.masked_status = status_byte(result);
1298		srp->header.msg_status = msg_byte(result);
1299		srp->header.host_status = host_byte(result);
1300		srp->header.driver_status = driver_byte(result);
1301		if ((sdp->sgdebug > 0) &&
1302		    ((CHECK_CONDITION == srp->header.masked_status) ||
1303		     (COMMAND_TERMINATED == srp->header.masked_status)))
1304			__scsi_print_sense("sg_cmd_done", sense,
1305					   SCSI_SENSE_BUFFERSIZE);
1306
1307		/* Following if statement is a patch supplied by Eric Youngdale */
1308		if (driver_byte(result) != 0
1309		    && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1310		    && !scsi_sense_is_deferred(&sshdr)
1311		    && sshdr.sense_key == UNIT_ATTENTION
1312		    && sdp->device->removable) {
1313			/* Detected possible disc change. Set the bit - this */
1314			/* may be used if there are filesystems using this device */
1315			sdp->device->changed = 1;
1316		}
1317	}
 
 
 
 
1318	/* Rely on write phase to clean out srp status values, so no "else" */
1319
 
 
 
 
 
 
 
 
 
 
1320	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1321	if (unlikely(srp->orphan)) {
1322		if (sfp->keep_orphan)
1323			srp->sg_io_owned = 0;
1324		else
1325			done = 0;
1326	}
1327	srp->done = done;
1328	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1329
1330	if (likely(done)) {
1331		/* Now wake up any sg_read() that is waiting for this
1332		 * packet.
1333		 */
1334		wake_up_interruptible(&sfp->read_wait);
1335		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1336		kref_put(&sfp->f_ref, sg_remove_sfp);
1337	} else {
1338		INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1339		schedule_work(&srp->ew.work);
1340	}
1341}
1342
1343static const struct file_operations sg_fops = {
1344	.owner = THIS_MODULE,
1345	.read = sg_read,
1346	.write = sg_write,
1347	.poll = sg_poll,
1348	.unlocked_ioctl = sg_unlocked_ioctl,
1349#ifdef CONFIG_COMPAT
1350	.compat_ioctl = sg_compat_ioctl,
1351#endif
1352	.open = sg_open,
1353	.mmap = sg_mmap,
1354	.release = sg_release,
1355	.fasync = sg_fasync,
1356	.llseek = no_llseek,
1357};
1358
1359static struct class *sg_sysfs_class;
1360
1361static int sg_sysfs_valid = 0;
1362
1363static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
 
1364{
1365	struct request_queue *q = scsidp->request_queue;
1366	Sg_device *sdp;
1367	unsigned long iflags;
1368	int error;
1369	u32 k;
1370
1371	sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1372	if (!sdp) {
1373		printk(KERN_WARNING "kmalloc Sg_device failure\n");
 
1374		return ERR_PTR(-ENOMEM);
1375	}
1376
1377	if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1378		printk(KERN_WARNING "idr expansion Sg_device failure\n");
1379		error = -ENOMEM;
1380		goto out;
1381	}
1382
1383	write_lock_irqsave(&sg_index_lock, iflags);
1384
1385	error = idr_get_new(&sg_index_idr, sdp, &k);
1386	if (error) {
1387		write_unlock_irqrestore(&sg_index_lock, iflags);
1388		printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1389		       error);
1390		goto out;
 
 
 
 
 
 
 
1391	}
 
1392
1393	if (unlikely(k >= SG_MAX_DEVS))
1394		goto overflow;
1395
1396	SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1397	sprintf(disk->disk_name, "sg%d", k);
1398	disk->first_minor = k;
1399	sdp->disk = disk;
1400	sdp->device = scsidp;
 
1401	INIT_LIST_HEAD(&sdp->sfds);
1402	init_waitqueue_head(&sdp->o_excl_wait);
 
 
1403	sdp->sg_tablesize = queue_max_segments(q);
1404	sdp->index = k;
1405	kref_init(&sdp->d_ref);
 
1406
 
1407	write_unlock_irqrestore(&sg_index_lock, iflags);
 
1408
1409	error = 0;
1410 out:
1411	if (error) {
1412		kfree(sdp);
1413		return ERR_PTR(error);
1414	}
1415	return sdp;
1416
1417 overflow:
1418	idr_remove(&sg_index_idr, k);
1419	write_unlock_irqrestore(&sg_index_lock, iflags);
1420	sdev_printk(KERN_WARNING, scsidp,
1421		    "Unable to attach sg device type=%d, minor "
1422		    "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1423	error = -ENODEV;
1424	goto out;
1425}
1426
1427static int
1428sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1429{
1430	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1431	struct gendisk *disk;
1432	Sg_device *sdp = NULL;
1433	struct cdev * cdev = NULL;
1434	int error;
1435	unsigned long iflags;
1436
1437	disk = alloc_disk(1);
1438	if (!disk) {
1439		printk(KERN_WARNING "alloc_disk failed\n");
1440		return -ENOMEM;
1441	}
1442	disk->major = SCSI_GENERIC_MAJOR;
1443
1444	error = -ENOMEM;
1445	cdev = cdev_alloc();
1446	if (!cdev) {
1447		printk(KERN_WARNING "cdev_alloc failed\n");
1448		goto out;
1449	}
1450	cdev->owner = THIS_MODULE;
1451	cdev->ops = &sg_fops;
1452
1453	sdp = sg_alloc(disk, scsidp);
1454	if (IS_ERR(sdp)) {
1455		printk(KERN_WARNING "sg_alloc failed\n");
1456		error = PTR_ERR(sdp);
1457		goto out;
1458	}
1459
1460	error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1461	if (error)
1462		goto cdev_add_err;
1463
1464	sdp->cdev = cdev;
1465	if (sg_sysfs_valid) {
1466		struct device *sg_class_member;
1467
1468		sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1469						MKDEV(SCSI_GENERIC_MAJOR,
1470						      sdp->index),
1471						sdp, "%s", disk->disk_name);
1472		if (IS_ERR(sg_class_member)) {
1473			printk(KERN_ERR "sg_add: "
1474			       "device_create failed\n");
1475			error = PTR_ERR(sg_class_member);
1476			goto cdev_add_err;
1477		}
1478		error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1479					  &sg_class_member->kobj, "generic");
1480		if (error)
1481			printk(KERN_ERR "sg_add: unable to make symlink "
1482					"'generic' back to sg%d\n", sdp->index);
1483	} else
1484		printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1485
1486	sdev_printk(KERN_NOTICE, scsidp,
1487		    "Attached scsi generic sg%d type %d\n", sdp->index,
1488		    scsidp->type);
1489
1490	dev_set_drvdata(cl_dev, sdp);
1491
1492	return 0;
1493
1494cdev_add_err:
1495	write_lock_irqsave(&sg_index_lock, iflags);
1496	idr_remove(&sg_index_idr, sdp->index);
1497	write_unlock_irqrestore(&sg_index_lock, iflags);
1498	kfree(sdp);
1499
1500out:
1501	put_disk(disk);
1502	if (cdev)
1503		cdev_del(cdev);
1504	return error;
1505}
1506
1507static void sg_device_destroy(struct kref *kref)
 
1508{
1509	struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1510	unsigned long flags;
1511
1512	/* CAUTION!  Note that the device can still be found via idr_find()
1513	 * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1514	 * any other cleanup.
1515	 */
1516
1517	write_lock_irqsave(&sg_index_lock, flags);
1518	idr_remove(&sg_index_idr, sdp->index);
1519	write_unlock_irqrestore(&sg_index_lock, flags);
1520
1521	SCSI_LOG_TIMEOUT(3,
1522		printk("sg_device_destroy: %s\n",
1523			sdp->disk->disk_name));
1524
1525	put_disk(sdp->disk);
1526	kfree(sdp);
1527}
1528
1529static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
 
1530{
1531	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1532	Sg_device *sdp = dev_get_drvdata(cl_dev);
1533	unsigned long iflags;
1534	Sg_fd *sfp;
 
1535
1536	if (!sdp || sdp->detached)
1537		return;
 
 
 
 
1538
1539	SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
 
1540
1541	/* Need a write lock to set sdp->detached. */
1542	write_lock_irqsave(&sg_index_lock, iflags);
1543	sdp->detached = 1;
1544	list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1545		wake_up_interruptible(&sfp->read_wait);
1546		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1547	}
1548	write_unlock_irqrestore(&sg_index_lock, iflags);
 
1549
1550	sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1551	device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1552	cdev_del(sdp->cdev);
1553	sdp->cdev = NULL;
1554
1555	sg_put_dev(sdp);
1556}
1557
1558module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1559module_param_named(def_reserved_size, def_reserved_size, int,
1560		   S_IRUGO | S_IWUSR);
1561module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1562
1563MODULE_AUTHOR("Douglas Gilbert");
1564MODULE_DESCRIPTION("SCSI generic (sg) driver");
1565MODULE_LICENSE("GPL");
1566MODULE_VERSION(SG_VERSION_STR);
1567MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1568
1569MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1570                "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1571MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1572MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1573
1574static int __init
1575init_sg(void)
1576{
1577	int rc;
1578
1579	if (scatter_elem_sz < PAGE_SIZE) {
1580		scatter_elem_sz = PAGE_SIZE;
1581		scatter_elem_sz_prev = scatter_elem_sz;
1582	}
1583	if (def_reserved_size >= 0)
1584		sg_big_buff = def_reserved_size;
1585	else
1586		def_reserved_size = sg_big_buff;
1587
1588	rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 
1589				    SG_MAX_DEVS, "sg");
1590	if (rc)
1591		return rc;
1592        sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1593        if ( IS_ERR(sg_sysfs_class) ) {
1594		rc = PTR_ERR(sg_sysfs_class);
1595		goto err_out;
1596        }
1597	sg_sysfs_valid = 1;
1598	rc = scsi_register_interface(&sg_interface);
1599	if (0 == rc) {
1600#ifdef CONFIG_SCSI_PROC_FS
1601		sg_proc_init();
1602#endif				/* CONFIG_SCSI_PROC_FS */
1603		return 0;
1604	}
1605	class_destroy(sg_sysfs_class);
1606err_out:
1607	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1608	return rc;
1609}
1610
1611static void __exit
1612exit_sg(void)
1613{
1614#ifdef CONFIG_SCSI_PROC_FS
1615	sg_proc_cleanup();
1616#endif				/* CONFIG_SCSI_PROC_FS */
1617	scsi_unregister_interface(&sg_interface);
1618	class_destroy(sg_sysfs_class);
1619	sg_sysfs_valid = 0;
1620	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1621				 SG_MAX_DEVS);
1622	idr_destroy(&sg_index_idr);
1623}
1624
1625static int sg_start_req(Sg_request *srp, unsigned char *cmd)
 
1626{
1627	int res;
1628	struct request *rq;
 
1629	Sg_fd *sfp = srp->parentfp;
1630	sg_io_hdr_t *hp = &srp->header;
1631	int dxfer_len = (int) hp->dxfer_len;
1632	int dxfer_dir = hp->dxfer_direction;
1633	unsigned int iov_count = hp->iovec_count;
1634	Sg_scatter_hold *req_schp = &srp->data;
1635	Sg_scatter_hold *rsv_schp = &sfp->reserve;
1636	struct request_queue *q = sfp->parentdp->device->request_queue;
1637	struct rq_map_data *md, map_data;
1638	int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
 
1639
1640	SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1641				   dxfer_len));
1642
1643	rq = blk_get_request(q, rw, GFP_ATOMIC);
1644	if (!rq)
1645		return -ENOMEM;
1646
1647	memcpy(rq->cmd, cmd, hp->cmd_len);
 
1648
1649	rq->cmd_len = hp->cmd_len;
1650	rq->cmd_type = REQ_TYPE_BLOCK_PC;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1651
1652	srp->rq = rq;
1653	rq->end_io_data = srp;
1654	rq->sense = srp->sense_b;
1655	rq->retries = SG_DEFAULT_RETRIES;
1656
1657	if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1658		return 0;
1659
1660	if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1661	    dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1662	    !sfp->parentdp->device->host->unchecked_isa_dma &&
1663	    blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1664		md = NULL;
1665	else
1666		md = &map_data;
1667
1668	if (md) {
1669		if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
 
 
 
1670			sg_link_reserve(sfp, srp, dxfer_len);
1671		else {
 
 
 
 
 
 
1672			res = sg_build_indirect(req_schp, sfp, dxfer_len);
1673			if (res)
 
1674				return res;
 
1675		}
 
1676
1677		md->pages = req_schp->pages;
1678		md->page_order = req_schp->page_order;
1679		md->nr_entries = req_schp->k_use_sg;
1680		md->offset = 0;
1681		md->null_mapped = hp->dxferp ? 0 : 1;
1682		if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1683			md->from_user = 1;
1684		else
1685			md->from_user = 0;
1686	}
1687
1688	if (iov_count) {
1689		int len, size = sizeof(struct sg_iovec) * iov_count;
1690		struct iovec *iov;
1691
1692		iov = memdup_user(hp->dxferp, size);
1693		if (IS_ERR(iov))
1694			return PTR_ERR(iov);
1695
1696		len = iov_length(iov, iov_count);
1697		if (hp->dxfer_len < len) {
1698			iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1699			len = hp->dxfer_len;
1700		}
1701
1702		res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1703					  iov_count,
1704					  len, GFP_ATOMIC);
 
 
 
 
 
1705		kfree(iov);
1706	} else
1707		res = blk_rq_map_user(q, rq, md, hp->dxferp,
1708				      hp->dxfer_len, GFP_ATOMIC);
1709
1710	if (!res) {
1711		srp->bio = rq->bio;
1712
1713		if (!md) {
1714			req_schp->dio_in_use = 1;
1715			hp->info |= SG_INFO_DIRECT_IO;
1716		}
1717	}
1718	return res;
1719}
1720
1721static int sg_finish_rem_req(Sg_request * srp)
 
1722{
1723	int ret = 0;
1724
1725	Sg_fd *sfp = srp->parentfp;
1726	Sg_scatter_hold *req_schp = &srp->data;
1727
1728	SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1729	if (srp->rq) {
1730		if (srp->bio)
1731			ret = blk_rq_unmap_user(srp->bio);
 
1732
 
 
1733		blk_put_request(srp->rq);
1734	}
1735
1736	if (srp->res_used)
1737		sg_unlink_reserve(sfp, srp);
1738	else
1739		sg_remove_scat(req_schp);
1740
1741	sg_remove_request(sfp, srp);
1742
1743	return ret;
1744}
1745
1746static int
1747sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1748{
1749	int sg_bufflen = tablesize * sizeof(struct page *);
1750	gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1751
1752	schp->pages = kzalloc(sg_bufflen, gfp_flags);
1753	if (!schp->pages)
1754		return -ENOMEM;
1755	schp->sglist_len = sg_bufflen;
1756	return tablesize;	/* number of scat_gath elements allocated */
1757}
1758
1759static int
1760sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1761{
1762	int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1763	int sg_tablesize = sfp->parentdp->sg_tablesize;
1764	int blk_size = buff_size, order;
1765	gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
 
1766
1767	if (blk_size < 0)
1768		return -EFAULT;
1769	if (0 == blk_size)
1770		++blk_size;	/* don't know why */
1771	/* round request up to next highest SG_SECTOR_SZ byte boundary */
1772	blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1773	SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1774				   buff_size, blk_size));
 
1775
1776	/* N.B. ret_sz carried into this block ... */
1777	mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1778	if (mx_sc_elems < 0)
1779		return mx_sc_elems;	/* most likely -ENOMEM */
1780
1781	num = scatter_elem_sz;
1782	if (unlikely(num != scatter_elem_sz_prev)) {
1783		if (num < PAGE_SIZE) {
1784			scatter_elem_sz = PAGE_SIZE;
1785			scatter_elem_sz_prev = PAGE_SIZE;
1786		} else
1787			scatter_elem_sz_prev = num;
1788	}
1789
1790	if (sfp->low_dma)
1791		gfp_mask |= GFP_DMA;
1792
1793	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1794		gfp_mask |= __GFP_ZERO;
1795
1796	order = get_order(num);
1797retry:
1798	ret_sz = 1 << (PAGE_SHIFT + order);
1799
1800	for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1801	     k++, rem_sz -= ret_sz) {
1802
1803		num = (rem_sz > scatter_elem_sz_prev) ?
1804			scatter_elem_sz_prev : rem_sz;
1805
1806		schp->pages[k] = alloc_pages(gfp_mask, order);
1807		if (!schp->pages[k])
1808			goto out;
1809
1810		if (num == scatter_elem_sz_prev) {
1811			if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1812				scatter_elem_sz = ret_sz;
1813				scatter_elem_sz_prev = ret_sz;
1814			}
1815		}
1816
1817		SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1818				 "ret_sz=%d\n", k, num, ret_sz));
 
1819	}		/* end of for loop */
1820
1821	schp->page_order = order;
1822	schp->k_use_sg = k;
1823	SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1824			 "rem_sz=%d\n", k, rem_sz));
 
1825
1826	schp->bufflen = blk_size;
1827	if (rem_sz > 0)	/* must have failed */
1828		return -ENOMEM;
1829	return 0;
1830out:
1831	for (i = 0; i < k; i++)
1832		__free_pages(schp->pages[i], order);
1833
1834	if (--order >= 0)
1835		goto retry;
1836
1837	return -ENOMEM;
1838}
1839
1840static void
1841sg_remove_scat(Sg_scatter_hold * schp)
1842{
1843	SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
 
1844	if (schp->pages && schp->sglist_len > 0) {
1845		if (!schp->dio_in_use) {
1846			int k;
1847
1848			for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1849				SCSI_LOG_TIMEOUT(5, printk(
1850				    "sg_remove_scat: k=%d, pg=0x%p\n",
1851				    k, schp->pages[k]));
 
1852				__free_pages(schp->pages[k], schp->page_order);
1853			}
1854
1855			kfree(schp->pages);
1856		}
1857	}
1858	memset(schp, 0, sizeof (*schp));
1859}
1860
1861static int
1862sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1863{
1864	Sg_scatter_hold *schp = &srp->data;
1865	int k, num;
1866
1867	SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1868				   num_read_xfer));
 
1869	if ((!outp) || (num_read_xfer <= 0))
1870		return 0;
1871
1872	num = 1 << (PAGE_SHIFT + schp->page_order);
1873	for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1874		if (num > num_read_xfer) {
1875			if (__copy_to_user(outp, page_address(schp->pages[k]),
1876					   num_read_xfer))
1877				return -EFAULT;
1878			break;
1879		} else {
1880			if (__copy_to_user(outp, page_address(schp->pages[k]),
1881					   num))
1882				return -EFAULT;
1883			num_read_xfer -= num;
1884			if (num_read_xfer <= 0)
1885				break;
1886			outp += num;
1887		}
1888	}
1889
1890	return 0;
1891}
1892
1893static void
1894sg_build_reserve(Sg_fd * sfp, int req_size)
1895{
1896	Sg_scatter_hold *schp = &sfp->reserve;
1897
1898	SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
 
1899	do {
1900		if (req_size < PAGE_SIZE)
1901			req_size = PAGE_SIZE;
1902		if (0 == sg_build_indirect(schp, sfp, req_size))
1903			return;
1904		else
1905			sg_remove_scat(schp);
1906		req_size >>= 1;	/* divide by 2 */
1907	} while (req_size > (PAGE_SIZE / 2));
1908}
1909
1910static void
1911sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1912{
1913	Sg_scatter_hold *req_schp = &srp->data;
1914	Sg_scatter_hold *rsv_schp = &sfp->reserve;
1915	int k, num, rem;
1916
1917	srp->res_used = 1;
1918	SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
 
1919	rem = size;
1920
1921	num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1922	for (k = 0; k < rsv_schp->k_use_sg; k++) {
1923		if (rem <= num) {
1924			req_schp->k_use_sg = k + 1;
1925			req_schp->sglist_len = rsv_schp->sglist_len;
1926			req_schp->pages = rsv_schp->pages;
1927
1928			req_schp->bufflen = size;
1929			req_schp->page_order = rsv_schp->page_order;
1930			break;
1931		} else
1932			rem -= num;
1933	}
1934
1935	if (k >= rsv_schp->k_use_sg)
1936		SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
 
1937}
1938
1939static void
1940sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1941{
1942	Sg_scatter_hold *req_schp = &srp->data;
1943
1944	SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1945				   (int) req_schp->k_use_sg));
 
1946	req_schp->k_use_sg = 0;
1947	req_schp->bufflen = 0;
1948	req_schp->pages = NULL;
1949	req_schp->page_order = 0;
1950	req_schp->sglist_len = 0;
1951	sfp->save_scat_len = 0;
1952	srp->res_used = 0;
 
 
1953}
1954
1955static Sg_request *
1956sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1957{
1958	Sg_request *resp;
1959	unsigned long iflags;
1960
1961	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1962	for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1963		/* look for requests that are ready + not SG_IO owned */
1964		if ((1 == resp->done) && (!resp->sg_io_owned) &&
1965		    ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1966			resp->done = 2;	/* guard against other readers */
1967			break;
 
1968		}
1969	}
1970	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1971	return resp;
1972}
1973
1974/* always adds to end of list */
1975static Sg_request *
1976sg_add_request(Sg_fd * sfp)
1977{
1978	int k;
1979	unsigned long iflags;
1980	Sg_request *resp;
1981	Sg_request *rp = sfp->req_arr;
1982
1983	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1984	resp = sfp->headrp;
1985	if (!resp) {
1986		memset(rp, 0, sizeof (Sg_request));
1987		rp->parentfp = sfp;
1988		resp = rp;
1989		sfp->headrp = resp;
1990	} else {
1991		if (0 == sfp->cmd_q)
1992			resp = NULL;	/* command queuing disallowed */
1993		else {
1994			for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
1995				if (!rp->parentfp)
1996					break;
1997			}
1998			if (k < SG_MAX_QUEUE) {
1999				memset(rp, 0, sizeof (Sg_request));
2000				rp->parentfp = sfp;
2001				while (resp->nextrp)
2002					resp = resp->nextrp;
2003				resp->nextrp = rp;
2004				resp = rp;
2005			} else
2006				resp = NULL;
2007		}
 
 
2008	}
2009	if (resp) {
2010		resp->nextrp = NULL;
2011		resp->header.duration = jiffies_to_msecs(jiffies);
2012	}
 
 
 
2013	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2014	return resp;
2015}
2016
2017/* Return of 1 for found; 0 for not found */
2018static int
2019sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2020{
2021	Sg_request *prev_rp;
2022	Sg_request *rp;
2023	unsigned long iflags;
2024	int res = 0;
2025
2026	if ((!sfp) || (!srp) || (!sfp->headrp))
2027		return res;
2028	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2029	prev_rp = sfp->headrp;
2030	if (srp == prev_rp) {
2031		sfp->headrp = prev_rp->nextrp;
2032		prev_rp->parentfp = NULL;
2033		res = 1;
2034	} else {
2035		while ((rp = prev_rp->nextrp)) {
2036			if (srp == rp) {
2037				prev_rp->nextrp = rp->nextrp;
2038				rp->parentfp = NULL;
2039				res = 1;
2040				break;
2041			}
2042			prev_rp = rp;
2043		}
2044	}
2045	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2046	return res;
2047}
2048
2049static Sg_fd *
2050sg_add_sfp(Sg_device * sdp, int dev)
2051{
2052	Sg_fd *sfp;
2053	unsigned long iflags;
2054	int bufflen;
2055
2056	sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2057	if (!sfp)
2058		return NULL;
2059
2060	init_waitqueue_head(&sfp->read_wait);
2061	rwlock_init(&sfp->rq_list_lock);
2062
2063	kref_init(&sfp->f_ref);
 
2064	sfp->timeout = SG_DEFAULT_TIMEOUT;
2065	sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2066	sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2067	sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2068	    sdp->device->host->unchecked_isa_dma : 1;
2069	sfp->cmd_q = SG_DEF_COMMAND_Q;
2070	sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2071	sfp->parentdp = sdp;
2072	write_lock_irqsave(&sg_index_lock, iflags);
 
 
 
 
 
2073	list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2074	write_unlock_irqrestore(&sg_index_lock, iflags);
2075	SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
 
2076	if (unlikely(sg_big_buff != def_reserved_size))
2077		sg_big_buff = def_reserved_size;
2078
2079	bufflen = min_t(int, sg_big_buff,
2080			queue_max_sectors(sdp->device->request_queue) * 512);
2081	sg_build_reserve(sfp, bufflen);
2082	SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2083			   sfp->reserve.bufflen, sfp->reserve.k_use_sg));
 
 
2084
2085	kref_get(&sdp->d_ref);
2086	__module_get(THIS_MODULE);
2087	return sfp;
2088}
2089
2090static void sg_remove_sfp_usercontext(struct work_struct *work)
 
2091{
2092	struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2093	struct sg_device *sdp = sfp->parentdp;
 
 
2094
2095	/* Cleanup any responses which were never read(). */
2096	while (sfp->headrp)
2097		sg_finish_rem_req(sfp->headrp);
 
 
 
 
 
 
2098
2099	if (sfp->reserve.bufflen > 0) {
2100		SCSI_LOG_TIMEOUT(6,
2101			printk("sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2102				(int) sfp->reserve.bufflen,
2103				(int) sfp->reserve.k_use_sg));
2104		sg_remove_scat(&sfp->reserve);
2105	}
2106
2107	SCSI_LOG_TIMEOUT(6,
2108		printk("sg_remove_sfp: %s, sfp=0x%p\n",
2109			sdp->disk->disk_name,
2110			sfp));
2111	kfree(sfp);
2112
2113	scsi_device_put(sdp->device);
2114	sg_put_dev(sdp);
2115	module_put(THIS_MODULE);
2116}
2117
2118static void sg_remove_sfp(struct kref *kref)
 
2119{
2120	struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2121	struct sg_device *sdp = sfp->parentdp;
2122	unsigned long iflags;
2123
2124	write_lock_irqsave(&sg_index_lock, iflags);
2125	list_del(&sfp->sfd_siblings);
2126	write_unlock_irqrestore(&sg_index_lock, iflags);
2127	wake_up_interruptible(&sdp->o_excl_wait);
2128
2129	INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2130	schedule_work(&sfp->ew.work);
2131}
2132
2133static int
2134sg_res_in_use(Sg_fd * sfp)
2135{
2136	const Sg_request *srp;
2137	unsigned long iflags;
2138
2139	read_lock_irqsave(&sfp->rq_list_lock, iflags);
2140	for (srp = sfp->headrp; srp; srp = srp->nextrp)
2141		if (srp->res_used)
2142			break;
2143	read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2144	return srp ? 1 : 0;
2145}
2146
2147#ifdef CONFIG_SCSI_PROC_FS
2148static int
2149sg_idr_max_id(int id, void *p, void *data)
2150{
2151	int *k = data;
2152
2153	if (*k < id)
2154		*k = id;
2155
2156	return 0;
2157}
2158
2159static int
2160sg_last_dev(void)
2161{
2162	int k = -1;
2163	unsigned long iflags;
2164
2165	read_lock_irqsave(&sg_index_lock, iflags);
2166	idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2167	read_unlock_irqrestore(&sg_index_lock, iflags);
2168	return k + 1;		/* origin 1 */
2169}
2170#endif
2171
2172/* must be called with sg_index_lock held */
2173static Sg_device *sg_lookup_dev(int dev)
2174{
2175	return idr_find(&sg_index_idr, dev);
2176}
2177
2178static Sg_device *sg_get_dev(int dev)
 
2179{
2180	struct sg_device *sdp;
2181	unsigned long flags;
2182
2183	read_lock_irqsave(&sg_index_lock, flags);
2184	sdp = sg_lookup_dev(dev);
2185	if (!sdp)
2186		sdp = ERR_PTR(-ENXIO);
2187	else if (sdp->detached) {
2188		/* If sdp->detached, then the refcount may already be 0, in
2189		 * which case it would be a bug to do kref_get().
2190		 */
2191		sdp = ERR_PTR(-ENODEV);
2192	} else
2193		kref_get(&sdp->d_ref);
2194	read_unlock_irqrestore(&sg_index_lock, flags);
2195
2196	return sdp;
2197}
2198
2199static void sg_put_dev(struct sg_device *sdp)
2200{
2201	kref_put(&sdp->d_ref, sg_device_destroy);
2202}
2203
2204#ifdef CONFIG_SCSI_PROC_FS
2205
2206static struct proc_dir_entry *sg_proc_sgp = NULL;
2207
2208static char sg_proc_sg_dirname[] = "scsi/sg";
2209
2210static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2211
2212static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2213static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2214			          size_t count, loff_t *off);
2215static const struct file_operations adio_fops = {
2216	.owner = THIS_MODULE,
2217	.open = sg_proc_single_open_adio,
2218	.read = seq_read,
2219	.llseek = seq_lseek,
2220	.write = sg_proc_write_adio,
2221	.release = single_release,
2222};
2223
2224static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2225static ssize_t sg_proc_write_dressz(struct file *filp, 
2226		const char __user *buffer, size_t count, loff_t *off);
2227static const struct file_operations dressz_fops = {
2228	.owner = THIS_MODULE,
2229	.open = sg_proc_single_open_dressz,
2230	.read = seq_read,
2231	.llseek = seq_lseek,
2232	.write = sg_proc_write_dressz,
2233	.release = single_release,
2234};
2235
2236static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2237static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2238static const struct file_operations version_fops = {
2239	.owner = THIS_MODULE,
2240	.open = sg_proc_single_open_version,
2241	.read = seq_read,
2242	.llseek = seq_lseek,
2243	.release = single_release,
2244};
2245
2246static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2247static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2248static const struct file_operations devhdr_fops = {
2249	.owner = THIS_MODULE,
2250	.open = sg_proc_single_open_devhdr,
2251	.read = seq_read,
2252	.llseek = seq_lseek,
2253	.release = single_release,
2254};
2255
2256static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2257static int sg_proc_open_dev(struct inode *inode, struct file *file);
2258static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2259static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2260static void dev_seq_stop(struct seq_file *s, void *v);
2261static const struct file_operations dev_fops = {
2262	.owner = THIS_MODULE,
2263	.open = sg_proc_open_dev,
2264	.read = seq_read,
2265	.llseek = seq_lseek,
2266	.release = seq_release,
2267};
2268static const struct seq_operations dev_seq_ops = {
2269	.start = dev_seq_start,
2270	.next  = dev_seq_next,
2271	.stop  = dev_seq_stop,
2272	.show  = sg_proc_seq_show_dev,
2273};
2274
2275static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2276static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2277static const struct file_operations devstrs_fops = {
2278	.owner = THIS_MODULE,
2279	.open = sg_proc_open_devstrs,
2280	.read = seq_read,
2281	.llseek = seq_lseek,
2282	.release = seq_release,
2283};
2284static const struct seq_operations devstrs_seq_ops = {
2285	.start = dev_seq_start,
2286	.next  = dev_seq_next,
2287	.stop  = dev_seq_stop,
2288	.show  = sg_proc_seq_show_devstrs,
2289};
2290
2291static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2292static int sg_proc_open_debug(struct inode *inode, struct file *file);
2293static const struct file_operations debug_fops = {
2294	.owner = THIS_MODULE,
2295	.open = sg_proc_open_debug,
2296	.read = seq_read,
2297	.llseek = seq_lseek,
2298	.release = seq_release,
2299};
2300static const struct seq_operations debug_seq_ops = {
2301	.start = dev_seq_start,
2302	.next  = dev_seq_next,
2303	.stop  = dev_seq_stop,
2304	.show  = sg_proc_seq_show_debug,
2305};
2306
2307
2308struct sg_proc_leaf {
2309	const char * name;
2310	const struct file_operations * fops;
2311};
2312
2313static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2314	{"allow_dio", &adio_fops},
2315	{"debug", &debug_fops},
2316	{"def_reserved_size", &dressz_fops},
2317	{"device_hdr", &devhdr_fops},
2318	{"devices", &dev_fops},
2319	{"device_strs", &devstrs_fops},
2320	{"version", &version_fops}
2321};
2322
2323static int
2324sg_proc_init(void)
2325{
2326	int k, mask;
2327	int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2328	struct sg_proc_leaf * leaf;
2329
2330	sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2331	if (!sg_proc_sgp)
2332		return 1;
2333	for (k = 0; k < num_leaves; ++k) {
2334		leaf = &sg_proc_leaf_arr[k];
2335		mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2336		proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2337	}
2338	return 0;
2339}
2340
2341static void
2342sg_proc_cleanup(void)
2343{
2344	int k;
2345	int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2346
2347	if (!sg_proc_sgp)
2348		return;
2349	for (k = 0; k < num_leaves; ++k)
2350		remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2351	remove_proc_entry(sg_proc_sg_dirname, NULL);
 
 
 
2352}
2353
2354
2355static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2356{
2357	seq_printf(s, "%d\n", *((int *)s->private));
2358	return 0;
2359}
2360
2361static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2362{
2363	return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2364}
2365
2366static ssize_t 
2367sg_proc_write_adio(struct file *filp, const char __user *buffer,
2368		   size_t count, loff_t *off)
2369{
2370	int num;
2371	char buff[11];
2372
2373	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2374		return -EACCES;
2375	num = (count < 10) ? count : 10;
2376	if (copy_from_user(buff, buffer, num))
2377		return -EFAULT;
2378	buff[num] = '\0';
2379	sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2380	return count;
2381}
2382
2383static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2384{
2385	return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2386}
2387
2388static ssize_t 
2389sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2390		     size_t count, loff_t *off)
2391{
2392	int num;
2393	unsigned long k = ULONG_MAX;
2394	char buff[11];
2395
2396	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2397		return -EACCES;
2398	num = (count < 10) ? count : 10;
2399	if (copy_from_user(buff, buffer, num))
2400		return -EFAULT;
2401	buff[num] = '\0';
2402	k = simple_strtoul(buff, NULL, 10);
2403	if (k <= 1048576) {	/* limit "big buff" to 1 MB */
2404		sg_big_buff = k;
2405		return count;
2406	}
2407	return -ERANGE;
2408}
2409
2410static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2411{
2412	seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2413		   sg_version_date);
2414	return 0;
2415}
2416
2417static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2418{
2419	return single_open(file, sg_proc_seq_show_version, NULL);
2420}
2421
2422static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2423{
2424	seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2425		   "online\n");
2426	return 0;
2427}
2428
2429static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2430{
2431	return single_open(file, sg_proc_seq_show_devhdr, NULL);
2432}
2433
2434struct sg_proc_deviter {
2435	loff_t	index;
2436	size_t	max;
2437};
2438
2439static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2440{
2441	struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2442
2443	s->private = it;
2444	if (! it)
2445		return NULL;
2446
2447	it->index = *pos;
2448	it->max = sg_last_dev();
2449	if (it->index >= it->max)
2450		return NULL;
2451	return it;
2452}
2453
2454static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2455{
2456	struct sg_proc_deviter * it = s->private;
2457
2458	*pos = ++it->index;
2459	return (it->index < it->max) ? it : NULL;
2460}
2461
2462static void dev_seq_stop(struct seq_file *s, void *v)
2463{
2464	kfree(s->private);
2465}
2466
2467static int sg_proc_open_dev(struct inode *inode, struct file *file)
2468{
2469        return seq_open(file, &dev_seq_ops);
2470}
2471
2472static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2473{
2474	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2475	Sg_device *sdp;
2476	struct scsi_device *scsidp;
2477	unsigned long iflags;
2478
2479	read_lock_irqsave(&sg_index_lock, iflags);
2480	sdp = it ? sg_lookup_dev(it->index) : NULL;
2481	if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2482		seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
 
 
 
 
2483			      scsidp->host->host_no, scsidp->channel,
2484			      scsidp->id, scsidp->lun, (int) scsidp->type,
2485			      1,
2486			      (int) scsidp->queue_depth,
2487			      (int) scsidp->device_busy,
2488			      (int) scsi_device_online(scsidp));
2489	else
2490		seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2491	read_unlock_irqrestore(&sg_index_lock, iflags);
2492	return 0;
2493}
2494
2495static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2496{
2497        return seq_open(file, &devstrs_seq_ops);
2498}
2499
2500static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2501{
2502	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2503	Sg_device *sdp;
2504	struct scsi_device *scsidp;
2505	unsigned long iflags;
2506
2507	read_lock_irqsave(&sg_index_lock, iflags);
2508	sdp = it ? sg_lookup_dev(it->index) : NULL;
2509	if (sdp && (scsidp = sdp->device) && (!sdp->detached))
 
2510		seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2511			   scsidp->vendor, scsidp->model, scsidp->rev);
2512	else
2513		seq_printf(s, "<no active device>\n");
2514	read_unlock_irqrestore(&sg_index_lock, iflags);
2515	return 0;
2516}
2517
2518/* must be called while holding sg_index_lock */
2519static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2520{
2521	int k, m, new_interface, blen, usg;
2522	Sg_request *srp;
2523	Sg_fd *fp;
2524	const sg_io_hdr_t *hp;
2525	const char * cp;
2526	unsigned int ms;
2527
2528	k = 0;
2529	list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2530		k++;
2531		read_lock(&fp->rq_list_lock); /* irqs already disabled */
2532		seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2533			   "(res)sgat=%d low_dma=%d\n", k,
2534			   jiffies_to_msecs(fp->timeout),
2535			   fp->reserve.bufflen,
2536			   (int) fp->reserve.k_use_sg,
2537			   (int) fp->low_dma);
2538		seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2539			   (int) fp->cmd_q, (int) fp->force_packid,
2540			   (int) fp->keep_orphan, (int) fp->closed);
2541		for (m = 0, srp = fp->headrp;
2542				srp != NULL;
2543				++m, srp = srp->nextrp) {
2544			hp = &srp->header;
2545			new_interface = (hp->interface_id == '\0') ? 0 : 1;
2546			if (srp->res_used) {
2547				if (new_interface && 
2548				    (SG_FLAG_MMAP_IO & hp->flags))
2549					cp = "     mmap>> ";
2550				else
2551					cp = "     rb>> ";
2552			} else {
2553				if (SG_INFO_DIRECT_IO_MASK & hp->info)
2554					cp = "     dio>> ";
2555				else
2556					cp = "     ";
2557			}
2558			seq_printf(s, cp);
2559			blen = srp->data.bufflen;
2560			usg = srp->data.k_use_sg;
2561			seq_printf(s, srp->done ? 
2562				   ((1 == srp->done) ?  "rcv:" : "fin:")
2563				   : "act:");
2564			seq_printf(s, " id=%d blen=%d",
2565				   srp->header.pack_id, blen);
2566			if (srp->done)
2567				seq_printf(s, " dur=%d", hp->duration);
2568			else {
2569				ms = jiffies_to_msecs(jiffies);
2570				seq_printf(s, " t_o/elap=%d/%d",
2571					(new_interface ? hp->timeout :
2572						  jiffies_to_msecs(fp->timeout)),
2573					(ms > hp->duration ? ms - hp->duration : 0));
2574			}
2575			seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2576				   (int) srp->data.cmd_opcode);
2577		}
2578		if (0 == m)
2579			seq_printf(s, "     No requests active\n");
2580		read_unlock(&fp->rq_list_lock);
2581	}
2582}
2583
2584static int sg_proc_open_debug(struct inode *inode, struct file *file)
2585{
2586        return seq_open(file, &debug_seq_ops);
2587}
2588
2589static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2590{
2591	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2592	Sg_device *sdp;
2593	unsigned long iflags;
2594
2595	if (it && (0 == it->index)) {
2596		seq_printf(s, "max_active_device=%d(origin 1)\n",
2597			   (int)it->max);
2598		seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2599	}
2600
2601	read_lock_irqsave(&sg_index_lock, iflags);
2602	sdp = it ? sg_lookup_dev(it->index) : NULL;
2603	if (sdp && !list_empty(&sdp->sfds)) {
2604		struct scsi_device *scsidp = sdp->device;
2605
 
2606		seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2607		if (sdp->detached)
2608			seq_printf(s, "detached pending close ");
2609		else
2610			seq_printf
2611			    (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2612			     scsidp->host->host_no,
2613			     scsidp->channel, scsidp->id,
2614			     scsidp->lun,
2615			     scsidp->host->hostt->emulated);
2616		seq_printf(s, " sg_tablesize=%d excl=%d\n",
2617			   sdp->sg_tablesize, sdp->exclude);
 
 
2618		sg_proc_debug_helper(s, sdp);
2619	}
 
 
2620	read_unlock_irqrestore(&sg_index_lock, iflags);
2621	return 0;
2622}
2623
2624#endif				/* CONFIG_SCSI_PROC_FS */
2625
2626module_init(init_sg);
2627module_exit(exit_sg);
v5.9
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  History:
   4 *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   5 *           to allow user process control of SCSI devices.
   6 *  Development Sponsored by Killy Corp. NY NY
   7 *
   8 * Original driver (sg.c):
   9 *        Copyright (C) 1992 Lawrence Foard
  10 * Version 2 and 3 extensions to driver:
  11 *        Copyright (C) 1998 - 2014 Douglas Gilbert
 
 
 
 
 
 
 
 
  12 */
  13
  14static int sg_version_num = 30536;	/* 2 digits for each component */
  15#define SG_VERSION_STR "3.5.36"
  16
  17/*
  18 *  D. P. Gilbert (dgilbert@interlog.com), notes:
  19 *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  20 *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  21 *        (otherwise the macros compile to empty statements).
  22 *
  23 */
  24#include <linux/module.h>
  25
  26#include <linux/fs.h>
  27#include <linux/kernel.h>
  28#include <linux/sched.h>
  29#include <linux/string.h>
  30#include <linux/mm.h>
  31#include <linux/errno.h>
  32#include <linux/mtio.h>
  33#include <linux/ioctl.h>
  34#include <linux/slab.h>
  35#include <linux/fcntl.h>
  36#include <linux/init.h>
  37#include <linux/poll.h>
  38#include <linux/moduleparam.h>
  39#include <linux/cdev.h>
  40#include <linux/idr.h>
  41#include <linux/seq_file.h>
  42#include <linux/blkdev.h>
  43#include <linux/delay.h>
  44#include <linux/blktrace_api.h>
  45#include <linux/mutex.h>
  46#include <linux/atomic.h>
  47#include <linux/ratelimit.h>
  48#include <linux/uio.h>
  49#include <linux/cred.h> /* for sg_check_file_access() */
  50
  51#include "scsi.h"
  52#include <scsi/scsi_dbg.h>
  53#include <scsi/scsi_host.h>
  54#include <scsi/scsi_driver.h>
  55#include <scsi/scsi_ioctl.h>
  56#include <scsi/sg.h>
  57
  58#include "scsi_logging.h"
  59
  60#ifdef CONFIG_SCSI_PROC_FS
  61#include <linux/proc_fs.h>
  62static char *sg_version_date = "20140603";
  63
  64static int sg_proc_init(void);
 
  65#endif
  66
  67#define SG_ALLOW_DIO_DEF 0
  68
  69#define SG_MAX_DEVS 32768
  70
  71/* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
  72 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
  73 * than 16 bytes are "variable length" whose length is a multiple of 4
 
 
 
 
 
  74 */
  75#define SG_MAX_CDB_SIZE 252
  76
  77#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  78
  79int sg_big_buff = SG_DEF_RESERVED_SIZE;
  80/* N.B. This variable is readable and writeable via
  81   /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  82   of this size (or less if there is not enough memory) will be reserved
  83   for use by this file descriptor. [Deprecated usage: this variable is also
  84   readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  85   the kernel (i.e. it is not a module).] */
  86static int def_reserved_size = -1;	/* picks up init parameter */
  87static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  88
  89static int scatter_elem_sz = SG_SCATTER_SZ;
  90static int scatter_elem_sz_prev = SG_SCATTER_SZ;
  91
  92#define SG_SECTOR_SZ 512
  93
  94static int sg_add_device(struct device *, struct class_interface *);
  95static void sg_remove_device(struct device *, struct class_interface *);
 
 
  96
  97static DEFINE_IDR(sg_index_idr);
  98static DEFINE_RWLOCK(sg_index_lock);	/* Also used to lock
  99							   file descriptor list for device */
 100
 101static struct class_interface sg_interface = {
 102	.add_dev        = sg_add_device,
 103	.remove_dev     = sg_remove_device,
 104};
 105
 106typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 107	unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 108	unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 109	unsigned bufflen;	/* Size of (aggregate) data buffer */
 110	struct page **pages;
 111	int page_order;
 112	char dio_in_use;	/* 0->indirect IO (or mmap), 1->dio */
 113	unsigned char cmd_opcode; /* first byte of command */
 114} Sg_scatter_hold;
 115
 116struct sg_device;		/* forward declarations */
 117struct sg_fd;
 118
 119typedef struct sg_request {	/* SG_MAX_QUEUE requests outstanding per file */
 120	struct list_head entry;	/* list entry */
 121	struct sg_fd *parentfp;	/* NULL -> not in use */
 122	Sg_scatter_hold data;	/* hold buffer, perhaps scatter list */
 123	sg_io_hdr_t header;	/* scsi command+info, see <scsi/sg.h> */
 124	unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 125	char res_used;		/* 1 -> using reserve buffer, 0 -> not ... */
 126	char orphan;		/* 1 -> drop on sight, 0 -> normal */
 127	char sg_io_owned;	/* 1 -> packet belongs to SG_IO */
 128	/* done protected by rq_list_lock */
 129	char done;		/* 0->before bh, 1->before read, 2->read */
 130	struct request *rq;
 131	struct bio *bio;
 132	struct execute_work ew;
 133} Sg_request;
 134
 135typedef struct sg_fd {		/* holds the state of a file descriptor */
 136	struct list_head sfd_siblings;  /* protected by device's sfd_lock */
 137	struct sg_device *parentdp;	/* owning device */
 138	wait_queue_head_t read_wait;	/* queue read until command done */
 139	rwlock_t rq_list_lock;	/* protect access to list in req_arr */
 140	struct mutex f_mutex;	/* protect against changes in this fd */
 141	int timeout;		/* defaults to SG_DEFAULT_TIMEOUT      */
 142	int timeout_user;	/* defaults to SG_DEFAULT_TIMEOUT_USER */
 143	Sg_scatter_hold reserve;	/* buffer held for this file descriptor */
 144	struct list_head rq_list; /* head of request list */
 
 145	struct fasync_struct *async_qp;	/* used by asynchronous notification */
 146	Sg_request req_arr[SG_MAX_QUEUE];	/* used as singly-linked list */
 
 147	char force_packid;	/* 1 -> pack_id input to read(), 0 -> ignored */
 
 148	char cmd_q;		/* 1 -> allow command queuing, 0 -> don't */
 149	unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
 150	char keep_orphan;	/* 0 -> drop orphan (def), 1 -> keep for read() */
 151	char mmap_called;	/* 0 -> mmap() never called on this fd */
 152	char res_in_use;	/* 1 -> 'reserve' array in use */
 153	struct kref f_ref;
 154	struct execute_work ew;
 155} Sg_fd;
 156
 157typedef struct sg_device { /* holds the state of each scsi generic device */
 158	struct scsi_device *device;
 159	wait_queue_head_t open_wait;    /* queue open() when O_EXCL present */
 160	struct mutex open_rel_lock;     /* held when in open() or release() */
 161	int sg_tablesize;	/* adapter's max scatter-gather table size */
 162	u32 index;		/* device index number */
 163	struct list_head sfds;
 164	rwlock_t sfd_lock;      /* protect access to sfd list */
 165	atomic_t detaching;     /* 0->device usable, 1->device detaching */
 166	bool exclude;		/* 1->open(O_EXCL) succeeded and is active */
 167	int open_cnt;		/* count of opens (perhaps < num(sfds) ) */
 168	char sgdebug;		/* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 169	struct gendisk *disk;
 170	struct cdev * cdev;	/* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 171	struct kref d_ref;
 172} Sg_device;
 173
 174/* tasklet or soft irq callback */
 175static void sg_rq_end_io(struct request *rq, blk_status_t status);
 176static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 177static int sg_finish_rem_req(Sg_request * srp);
 178static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 179static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 180			   Sg_request * srp);
 181static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 182			const char __user *buf, size_t count, int blocking,
 183			int read_only, int sg_io_owned, Sg_request **o_srp);
 184static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 185			   unsigned char *cmnd, int timeout, int blocking);
 186static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 187static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
 188static void sg_build_reserve(Sg_fd * sfp, int req_size);
 189static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 190static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 191static Sg_fd *sg_add_sfp(Sg_device * sdp);
 192static void sg_remove_sfp(struct kref *);
 193static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 194static Sg_request *sg_add_request(Sg_fd * sfp);
 195static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 
 196static Sg_device *sg_get_dev(int dev);
 197static void sg_device_destroy(struct kref *kref);
 198
 199#define SZ_SG_HEADER sizeof(struct sg_header)
 200#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 201#define SZ_SG_IOVEC sizeof(sg_iovec_t)
 202#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 203
 204#define sg_printk(prefix, sdp, fmt, a...) \
 205	sdev_prefix_printk(prefix, (sdp)->device,		\
 206			   (sdp)->disk->disk_name, fmt, ##a)
 207
 208/*
 209 * The SCSI interfaces that use read() and write() as an asynchronous variant of
 210 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
 211 * to trigger read() and write() calls from various contexts with elevated
 212 * privileges. This can lead to kernel memory corruption (e.g. if these
 213 * interfaces are called through splice()) and privilege escalation inside
 214 * userspace (e.g. if a process with access to such a device passes a file
 215 * descriptor to a SUID binary as stdin/stdout/stderr).
 216 *
 217 * This function provides protection for the legacy API by restricting the
 218 * calling context.
 219 */
 220static int sg_check_file_access(struct file *filp, const char *caller)
 221{
 222	if (filp->f_cred != current_real_cred()) {
 223		pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
 224			caller, task_tgid_vnr(current), current->comm);
 225		return -EPERM;
 226	}
 227	if (uaccess_kernel()) {
 228		pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
 229			caller, task_tgid_vnr(current), current->comm);
 230		return -EACCES;
 231	}
 232	return 0;
 233}
 234
 235static int sg_allow_access(struct file *filp, unsigned char *cmd)
 236{
 237	struct sg_fd *sfp = filp->private_data;
 238
 239	if (sfp->parentdp->device->type == TYPE_SCANNER)
 240		return 0;
 241
 242	return blk_verify_command(cmd, filp->f_mode);
 243}
 244
 245static int
 246open_wait(Sg_device *sdp, int flags)
 247{
 248	int retval = 0;
 249
 250	if (flags & O_EXCL) {
 251		while (sdp->open_cnt > 0) {
 252			mutex_unlock(&sdp->open_rel_lock);
 253			retval = wait_event_interruptible(sdp->open_wait,
 254					(atomic_read(&sdp->detaching) ||
 255					 !sdp->open_cnt));
 256			mutex_lock(&sdp->open_rel_lock);
 257
 258			if (retval) /* -ERESTARTSYS */
 259				return retval;
 260			if (atomic_read(&sdp->detaching))
 261				return -ENODEV;
 262		}
 263	} else {
 264		while (sdp->exclude) {
 265			mutex_unlock(&sdp->open_rel_lock);
 266			retval = wait_event_interruptible(sdp->open_wait,
 267					(atomic_read(&sdp->detaching) ||
 268					 !sdp->exclude));
 269			mutex_lock(&sdp->open_rel_lock);
 270
 271			if (retval) /* -ERESTARTSYS */
 272				return retval;
 273			if (atomic_read(&sdp->detaching))
 274				return -ENODEV;
 275		}
 276	}
 277
 278	return retval;
 279}
 280
 281/* Returns 0 on success, else a negated errno value */
 282static int
 283sg_open(struct inode *inode, struct file *filp)
 284{
 285	int dev = iminor(inode);
 286	int flags = filp->f_flags;
 287	struct request_queue *q;
 288	Sg_device *sdp;
 289	Sg_fd *sfp;
 
 290	int retval;
 291
 
 292	nonseekable_open(inode, filp);
 293	if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
 294		return -EPERM; /* Can't lock it with read only access */
 295	sdp = sg_get_dev(dev);
 296	if (IS_ERR(sdp))
 297		return PTR_ERR(sdp);
 298
 299	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 300				      "sg_open: flags=0x%x\n", flags));
 301
 302	/* This driver's module count bumped by fops_get in <linux/fs.h> */
 303	/* Prevent the device driver from vanishing while we sleep */
 304	retval = scsi_device_get(sdp->device);
 305	if (retval)
 306		goto sg_put;
 307
 308	retval = scsi_autopm_get_device(sdp->device);
 309	if (retval)
 310		goto sdp_put;
 311
 312	/* scsi_block_when_processing_errors() may block so bypass
 313	 * check if O_NONBLOCK. Permits SCSI commands to be issued
 314	 * during error recovery. Tread carefully. */
 315	if (!((flags & O_NONBLOCK) ||
 316	      scsi_block_when_processing_errors(sdp->device))) {
 317		retval = -ENXIO;
 318		/* we are in error recovery for this device */
 319		goto error_out;
 320	}
 321
 322	mutex_lock(&sdp->open_rel_lock);
 323	if (flags & O_NONBLOCK) {
 324		if (flags & O_EXCL) {
 325			if (sdp->open_cnt > 0) {
 326				retval = -EBUSY;
 327				goto error_mutex_locked;
 328			}
 329		} else {
 330			if (sdp->exclude) {
 331				retval = -EBUSY;
 332				goto error_mutex_locked;
 333			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 334		}
 335	} else {
 336		retval = open_wait(sdp, flags);
 337		if (retval) /* -ERESTARTSYS or -ENODEV */
 338			goto error_mutex_locked;
 339	}
 340
 341	/* N.B. at this point we are holding the open_rel_lock */
 342	if (flags & O_EXCL)
 343		sdp->exclude = true;
 344
 345	if (sdp->open_cnt < 1) {  /* no existing opens */
 346		sdp->sgdebug = 0;
 347		q = sdp->device->request_queue;
 348		sdp->sg_tablesize = queue_max_segments(q);
 349	}
 350	sfp = sg_add_sfp(sdp);
 351	if (IS_ERR(sfp)) {
 352		retval = PTR_ERR(sfp);
 353		goto out_undo;
 
 
 
 
 
 354	}
 355
 356	filp->private_data = sfp;
 357	sdp->open_cnt++;
 358	mutex_unlock(&sdp->open_rel_lock);
 359
 360	retval = 0;
 
 
 
 
 
 
 361sg_put:
 362	kref_put(&sdp->d_ref, sg_device_destroy);
 
 
 363	return retval;
 364
 365out_undo:
 366	if (flags & O_EXCL) {
 367		sdp->exclude = false;   /* undo if error */
 368		wake_up_interruptible(&sdp->open_wait);
 369	}
 370error_mutex_locked:
 371	mutex_unlock(&sdp->open_rel_lock);
 372error_out:
 373	scsi_autopm_put_device(sdp->device);
 374sdp_put:
 375	scsi_device_put(sdp->device);
 376	goto sg_put;
 377}
 378
 379/* Release resources associated with a successful sg_open()
 380 * Returns 0 on success, else a negated errno value */
 381static int
 382sg_release(struct inode *inode, struct file *filp)
 383{
 384	Sg_device *sdp;
 385	Sg_fd *sfp;
 386
 387	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 388		return -ENXIO;
 389	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
 
 
 
 
 
 390
 391	mutex_lock(&sdp->open_rel_lock);
 392	scsi_autopm_put_device(sdp->device);
 393	kref_put(&sfp->f_ref, sg_remove_sfp);
 394	sdp->open_cnt--;
 395
 396	/* possibly many open()s waiting on exlude clearing, start many;
 397	 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
 398	if (sdp->exclude) {
 399		sdp->exclude = false;
 400		wake_up_interruptible_all(&sdp->open_wait);
 401	} else if (0 == sdp->open_cnt) {
 402		wake_up_interruptible(&sdp->open_wait);
 403	}
 404	mutex_unlock(&sdp->open_rel_lock);
 405	return 0;
 406}
 407
 408static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count)
 409{
 410	struct sg_header __user *old_hdr = buf;
 411	int reply_len;
 412
 413	if (count >= SZ_SG_HEADER) {
 414		/* negative reply_len means v3 format, otherwise v1/v2 */
 415		if (get_user(reply_len, &old_hdr->reply_len))
 416			return -EFAULT;
 417
 418		if (reply_len >= 0)
 419			return get_user(*pack_id, &old_hdr->pack_id);
 420
 421		if (in_compat_syscall() &&
 422		    count >= sizeof(struct compat_sg_io_hdr)) {
 423			struct compat_sg_io_hdr __user *hp = buf;
 424
 425			return get_user(*pack_id, &hp->pack_id);
 426		}
 427
 428		if (count >= sizeof(struct sg_io_hdr)) {
 429			struct sg_io_hdr __user *hp = buf;
 430
 431			return get_user(*pack_id, &hp->pack_id);
 432		}
 433	}
 434
 435	/* no valid header was passed, so ignore the pack_id */
 436	*pack_id = -1;
 437	return 0;
 438}
 439
 440static ssize_t
 441sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 442{
 443	Sg_device *sdp;
 444	Sg_fd *sfp;
 445	Sg_request *srp;
 446	int req_pack_id = -1;
 447	sg_io_hdr_t *hp;
 448	struct sg_header *old_hdr;
 449	int retval;
 450
 451	/*
 452	 * This could cause a response to be stranded. Close the associated
 453	 * file descriptor to free up any resources being held.
 454	 */
 455	retval = sg_check_file_access(filp, __func__);
 456	if (retval)
 457		return retval;
 458
 459	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 460		return -ENXIO;
 461	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 462				      "sg_read: count=%d\n", (int) count));
 463
 464	if (sfp->force_packid)
 465		retval = get_sg_io_pack_id(&req_pack_id, buf, count);
 466	if (retval)
 467		return retval;
 468
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 469	srp = sg_get_rq_mark(sfp, req_pack_id);
 470	if (!srp) {		/* now wait on packet to arrive */
 471		if (atomic_read(&sdp->detaching))
 472			return -ENODEV;
 473		if (filp->f_flags & O_NONBLOCK)
 474			return -EAGAIN;
 475		retval = wait_event_interruptible(sfp->read_wait,
 476			(atomic_read(&sdp->detaching) ||
 477			(srp = sg_get_rq_mark(sfp, req_pack_id))));
 478		if (atomic_read(&sdp->detaching))
 479			return -ENODEV;
 480		if (retval)
 
 
 
 
 
 
 
 
 
 
 
 481			/* -ERESTARTSYS as signal hit process */
 482			return retval;
 
 
 
 
 
 483	}
 484	if (srp->header.interface_id != '\0')
 485		return sg_new_read(sfp, buf, count, srp);
 486
 487	hp = &srp->header;
 488	old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL);
 489	if (!old_hdr)
 490		return -ENOMEM;
 491
 
 
 
 
 492	old_hdr->reply_len = (int) hp->timeout;
 493	old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 494	old_hdr->pack_id = hp->pack_id;
 495	old_hdr->twelve_byte =
 496	    ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 497	old_hdr->target_status = hp->masked_status;
 498	old_hdr->host_status = hp->host_status;
 499	old_hdr->driver_status = hp->driver_status;
 500	if ((CHECK_CONDITION & hp->masked_status) ||
 501	    (DRIVER_SENSE & hp->driver_status))
 502		memcpy(old_hdr->sense_buffer, srp->sense_b,
 503		       sizeof (old_hdr->sense_buffer));
 504	switch (hp->host_status) {
 505	/* This setup of 'result' is for backward compatibility and is best
 506	   ignored by the user who should use target, host + driver status */
 507	case DID_OK:
 508	case DID_PASSTHROUGH:
 509	case DID_SOFT_ERROR:
 510		old_hdr->result = 0;
 511		break;
 512	case DID_NO_CONNECT:
 513	case DID_BUS_BUSY:
 514	case DID_TIME_OUT:
 515		old_hdr->result = EBUSY;
 516		break;
 517	case DID_BAD_TARGET:
 518	case DID_ABORT:
 519	case DID_PARITY:
 520	case DID_RESET:
 521	case DID_BAD_INTR:
 522		old_hdr->result = EIO;
 523		break;
 524	case DID_ERROR:
 525		old_hdr->result = (srp->sense_b[0] == 0 && 
 526				  hp->masked_status == GOOD) ? 0 : EIO;
 527		break;
 528	default:
 529		old_hdr->result = EIO;
 530		break;
 531	}
 532
 533	/* Now copy the result back to the user buffer.  */
 534	if (count >= SZ_SG_HEADER) {
 535		if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 536			retval = -EFAULT;
 537			goto free_old_hdr;
 538		}
 539		buf += SZ_SG_HEADER;
 540		if (count > old_hdr->reply_len)
 541			count = old_hdr->reply_len;
 542		if (count > SZ_SG_HEADER) {
 543			if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 544				retval = -EFAULT;
 545				goto free_old_hdr;
 546			}
 547		}
 548	} else
 549		count = (old_hdr->result == 0) ? 0 : -EIO;
 550	sg_finish_rem_req(srp);
 551	sg_remove_request(sfp, srp);
 552	retval = count;
 553free_old_hdr:
 554	kfree(old_hdr);
 555	return retval;
 556}
 557
 558static ssize_t
 559sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 560{
 561	sg_io_hdr_t *hp = &srp->header;
 562	int err = 0, err2;
 563	int len;
 564
 565	if (in_compat_syscall()) {
 566		if (count < sizeof(struct compat_sg_io_hdr)) {
 567			err = -EINVAL;
 568			goto err_out;
 569		}
 570	} else if (count < SZ_SG_IO_HDR) {
 571		err = -EINVAL;
 572		goto err_out;
 573	}
 574	hp->sb_len_wr = 0;
 575	if ((hp->mx_sb_len > 0) && hp->sbp) {
 576		if ((CHECK_CONDITION & hp->masked_status) ||
 577		    (DRIVER_SENSE & hp->driver_status)) {
 578			int sb_len = SCSI_SENSE_BUFFERSIZE;
 579			sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 580			len = 8 + (int) srp->sense_b[7];	/* Additional sense length field */
 581			len = (len > sb_len) ? sb_len : len;
 582			if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 583				err = -EFAULT;
 584				goto err_out;
 585			}
 586			hp->sb_len_wr = len;
 587		}
 588	}
 589	if (hp->masked_status || hp->host_status || hp->driver_status)
 590		hp->info |= SG_INFO_CHECK;
 591	err = put_sg_io_hdr(hp, buf);
 
 
 
 592err_out:
 593	err2 = sg_finish_rem_req(srp);
 594	sg_remove_request(sfp, srp);
 595	return err ? : err2 ? : count;
 596}
 597
 598static ssize_t
 599sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 600{
 601	int mxsize, cmd_size, k;
 602	int input_size, blocking;
 603	unsigned char opcode;
 604	Sg_device *sdp;
 605	Sg_fd *sfp;
 606	Sg_request *srp;
 607	struct sg_header old_hdr;
 608	sg_io_hdr_t *hp;
 609	unsigned char cmnd[SG_MAX_CDB_SIZE];
 610	int retval;
 611
 612	retval = sg_check_file_access(filp, __func__);
 613	if (retval)
 614		return retval;
 615
 616	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 617		return -ENXIO;
 618	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 619				      "sg_write: count=%d\n", (int) count));
 620	if (atomic_read(&sdp->detaching))
 621		return -ENODEV;
 622	if (!((filp->f_flags & O_NONBLOCK) ||
 623	      scsi_block_when_processing_errors(sdp->device)))
 624		return -ENXIO;
 625
 
 
 626	if (count < SZ_SG_HEADER)
 627		return -EIO;
 628	if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 629		return -EFAULT;
 630	blocking = !(filp->f_flags & O_NONBLOCK);
 631	if (old_hdr.reply_len < 0)
 632		return sg_new_write(sfp, filp, buf, count,
 633				    blocking, 0, 0, NULL);
 634	if (count < (SZ_SG_HEADER + 6))
 635		return -EIO;	/* The minimum scsi command length is 6 bytes. */
 636
 637	buf += SZ_SG_HEADER;
 638	if (get_user(opcode, buf))
 639		return -EFAULT;
 640
 641	if (!(srp = sg_add_request(sfp))) {
 642		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
 643					      "sg_write: queue full\n"));
 644		return -EDOM;
 645	}
 646	mutex_lock(&sfp->f_mutex);
 
 647	if (sfp->next_cmd_len > 0) {
 
 
 
 
 
 
 648		cmd_size = sfp->next_cmd_len;
 649		sfp->next_cmd_len = 0;	/* reset so only this write() effected */
 650	} else {
 651		cmd_size = COMMAND_SIZE(opcode);	/* based on SCSI command group */
 652		if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 653			cmd_size = 12;
 654	}
 655	mutex_unlock(&sfp->f_mutex);
 656	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
 657		"sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 658/* Determine buffer size.  */
 659	input_size = count - cmd_size;
 660	mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 661	mxsize -= SZ_SG_HEADER;
 662	input_size -= SZ_SG_HEADER;
 663	if (input_size < 0) {
 664		sg_remove_request(sfp, srp);
 665		return -EIO;	/* User did not pass enough bytes for this command. */
 666	}
 667	hp = &srp->header;
 668	hp->interface_id = '\0';	/* indicator of old interface tunnelled */
 669	hp->cmd_len = (unsigned char) cmd_size;
 670	hp->iovec_count = 0;
 671	hp->mx_sb_len = 0;
 672	if (input_size > 0)
 673		hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 674		    SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 675	else
 676		hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 677	hp->dxfer_len = mxsize;
 678	if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
 679	    (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
 680		hp->dxferp = (char __user *)buf + cmd_size;
 681	else
 682		hp->dxferp = NULL;
 683	hp->sbp = NULL;
 684	hp->timeout = old_hdr.reply_len;	/* structure abuse ... */
 685	hp->flags = input_size;	/* structure abuse ... */
 686	hp->pack_id = old_hdr.pack_id;
 687	hp->usr_ptr = NULL;
 688	if (copy_from_user(cmnd, buf, cmd_size)) {
 689		sg_remove_request(sfp, srp);
 690		return -EFAULT;
 691	}
 692	/*
 693	 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 694	 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 695	 * is a non-zero input_size, so emit a warning.
 696	 */
 697	if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 698		printk_ratelimited(KERN_WARNING
 699				   "sg_write: data in/out %d/%d bytes "
 700				   "for SCSI command 0x%x-- guessing "
 701				   "data in;\n   program %s not setting "
 702				   "count and/or reply_len properly\n",
 703				   old_hdr.reply_len - (int)SZ_SG_HEADER,
 704				   input_size, (unsigned int) cmnd[0],
 705				   current->comm);
 
 
 
 706	}
 707	k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 708	return (k < 0) ? k : count;
 709}
 710
 711static ssize_t
 712sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 713		 size_t count, int blocking, int read_only, int sg_io_owned,
 714		 Sg_request **o_srp)
 715{
 716	int k;
 717	Sg_request *srp;
 718	sg_io_hdr_t *hp;
 719	unsigned char cmnd[SG_MAX_CDB_SIZE];
 720	int timeout;
 721	unsigned long ul_timeout;
 722
 723	if (count < SZ_SG_IO_HDR)
 724		return -EINVAL;
 
 
 725
 726	sfp->cmd_q = 1;	/* when sg_io_hdr seen, set command queuing on */
 727	if (!(srp = sg_add_request(sfp))) {
 728		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
 729					      "sg_new_write: queue full\n"));
 730		return -EDOM;
 731	}
 732	srp->sg_io_owned = sg_io_owned;
 733	hp = &srp->header;
 734	if (get_sg_io_hdr(hp, buf)) {
 735		sg_remove_request(sfp, srp);
 736		return -EFAULT;
 737	}
 738	if (hp->interface_id != 'S') {
 739		sg_remove_request(sfp, srp);
 740		return -ENOSYS;
 741	}
 742	if (hp->flags & SG_FLAG_MMAP_IO) {
 743		if (hp->dxfer_len > sfp->reserve.bufflen) {
 744			sg_remove_request(sfp, srp);
 745			return -ENOMEM;	/* MMAP_IO size must fit in reserve buffer */
 746		}
 747		if (hp->flags & SG_FLAG_DIRECT_IO) {
 748			sg_remove_request(sfp, srp);
 749			return -EINVAL;	/* either MMAP_IO or DIRECT_IO (not both) */
 750		}
 751		if (sfp->res_in_use) {
 752			sg_remove_request(sfp, srp);
 753			return -EBUSY;	/* reserve buffer already being used */
 754		}
 755	}
 756	ul_timeout = msecs_to_jiffies(srp->header.timeout);
 757	timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 758	if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 759		sg_remove_request(sfp, srp);
 760		return -EMSGSIZE;
 761	}
 762	if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 
 
 
 
 763		sg_remove_request(sfp, srp);
 764		return -EFAULT;
 765	}
 766	if (read_only && sg_allow_access(file, cmnd)) {
 767		sg_remove_request(sfp, srp);
 768		return -EPERM;
 769	}
 770	k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 771	if (k < 0)
 772		return k;
 773	if (o_srp)
 774		*o_srp = srp;
 775	return count;
 776}
 777
 778static int
 779sg_common_write(Sg_fd * sfp, Sg_request * srp,
 780		unsigned char *cmnd, int timeout, int blocking)
 781{
 782	int k, at_head;
 783	Sg_device *sdp = sfp->parentdp;
 784	sg_io_hdr_t *hp = &srp->header;
 785
 786	srp->data.cmd_opcode = cmnd[0];	/* hold opcode of command */
 787	hp->status = 0;
 788	hp->masked_status = 0;
 789	hp->msg_status = 0;
 790	hp->info = 0;
 791	hp->host_status = 0;
 792	hp->driver_status = 0;
 793	hp->resid = 0;
 794	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
 795			"sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 796			(int) cmnd[0], (int) hp->cmd_len));
 797
 798	if (hp->dxfer_len >= SZ_256M) {
 799		sg_remove_request(sfp, srp);
 800		return -EINVAL;
 801	}
 802
 803	k = sg_start_req(srp, cmnd);
 804	if (k) {
 805		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
 806			"sg_common_write: start_req err=%d\n", k));
 807		sg_finish_rem_req(srp);
 808		sg_remove_request(sfp, srp);
 809		return k;	/* probably out of space --> ENOMEM */
 810	}
 811	if (atomic_read(&sdp->detaching)) {
 812		if (srp->bio) {
 813			scsi_req_free_cmd(scsi_req(srp->rq));
 814			blk_put_request(srp->rq);
 815			srp->rq = NULL;
 816		}
 817
 818		sg_finish_rem_req(srp);
 819		sg_remove_request(sfp, srp);
 820		return -ENODEV;
 821	}
 822
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 823	hp->duration = jiffies_to_msecs(jiffies);
 824	if (hp->interface_id != '\0' &&	/* v3 (or later) interface */
 825	    (SG_FLAG_Q_AT_TAIL & hp->flags))
 826		at_head = 0;
 827	else
 828		at_head = 1;
 829
 830	srp->rq->timeout = timeout;
 831	kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
 832	blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 833			      srp->rq, at_head, sg_rq_end_io);
 834	return 0;
 835}
 836
 837static int srp_done(Sg_fd *sfp, Sg_request *srp)
 838{
 839	unsigned long flags;
 840	int ret;
 841
 842	read_lock_irqsave(&sfp->rq_list_lock, flags);
 843	ret = srp->done;
 844	read_unlock_irqrestore(&sfp->rq_list_lock, flags);
 845	return ret;
 846}
 847
 848static int max_sectors_bytes(struct request_queue *q)
 849{
 850	unsigned int max_sectors = queue_max_sectors(q);
 851
 852	max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
 853
 854	return max_sectors << 9;
 855}
 856
 857static void
 858sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
 859{
 860	Sg_request *srp;
 861	int val;
 862	unsigned int ms;
 863
 864	val = 0;
 865	list_for_each_entry(srp, &sfp->rq_list, entry) {
 866		if (val >= SG_MAX_QUEUE)
 867			break;
 868		rinfo[val].req_state = srp->done + 1;
 869		rinfo[val].problem =
 870			srp->header.masked_status &
 871			srp->header.host_status &
 872			srp->header.driver_status;
 873		if (srp->done)
 874			rinfo[val].duration =
 875				srp->header.duration;
 876		else {
 877			ms = jiffies_to_msecs(jiffies);
 878			rinfo[val].duration =
 879				(ms > srp->header.duration) ?
 880				(ms - srp->header.duration) : 0;
 881		}
 882		rinfo[val].orphan = srp->orphan;
 883		rinfo[val].sg_io_owned = srp->sg_io_owned;
 884		rinfo[val].pack_id = srp->header.pack_id;
 885		rinfo[val].usr_ptr = srp->header.usr_ptr;
 886		val++;
 887	}
 888}
 889
 890#ifdef CONFIG_COMPAT
 891struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
 892	char req_state;
 893	char orphan;
 894	char sg_io_owned;
 895	char problem;
 896	int pack_id;
 897	compat_uptr_t usr_ptr;
 898	unsigned int duration;
 899	int unused;
 900};
 901
 902static int put_compat_request_table(struct compat_sg_req_info __user *o,
 903				    struct sg_req_info *rinfo)
 904{
 905	int i;
 906	for (i = 0; i < SG_MAX_QUEUE; i++) {
 907		if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
 908		    put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
 909		    put_user(rinfo[i].duration, &o[i].duration) ||
 910		    put_user(rinfo[i].unused, &o[i].unused))
 911			return -EFAULT;
 912	}
 913	return 0;
 914}
 915#endif
 916
 917static long
 918sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
 919		unsigned int cmd_in, void __user *p)
 920{
 
 921	int __user *ip = p;
 922	int result, val, read_only;
 
 
 923	Sg_request *srp;
 924	unsigned long iflags;
 925
 926	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 927				   "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
 
 
 
 928	read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 929
 930	switch (cmd_in) {
 931	case SG_IO:
 932		if (atomic_read(&sdp->detaching))
 933			return -ENODEV;
 934		if (!scsi_block_when_processing_errors(sdp->device))
 935			return -ENXIO;
 936		result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 937				 1, read_only, 1, &srp);
 938		if (result < 0)
 939			return result;
 940		result = wait_event_interruptible(sfp->read_wait,
 941			(srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
 942		if (atomic_read(&sdp->detaching))
 943			return -ENODEV;
 944		write_lock_irq(&sfp->rq_list_lock);
 945		if (srp->done) {
 946			srp->done = 2;
 947			write_unlock_irq(&sfp->rq_list_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 948			result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 949			return (result < 0) ? result : 0;
 950		}
 951		srp->orphan = 1;
 952		write_unlock_irq(&sfp->rq_list_lock);
 953		return result;	/* -ERESTARTSYS because signal hit process */
 954	case SG_SET_TIMEOUT:
 955		result = get_user(val, ip);
 956		if (result)
 957			return result;
 958		if (val < 0)
 959			return -EIO;
 960		if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
 961			val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
 962				    INT_MAX);
 963		sfp->timeout_user = val;
 964		sfp->timeout = mult_frac(val, HZ, USER_HZ);
 965
 966		return 0;
 967	case SG_GET_TIMEOUT:	/* N.B. User receives timeout as return value */
 968				/* strange ..., for backward compatibility */
 969		return sfp->timeout_user;
 970	case SG_SET_FORCE_LOW_DMA:
 971		/*
 972		 * N.B. This ioctl never worked properly, but failed to
 973		 * return an error value. So returning '0' to keep compability
 974		 * with legacy applications.
 975		 */
 
 
 
 
 
 
 
 
 
 
 976		return 0;
 977	case SG_GET_LOW_DMA:
 978		return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
 979	case SG_GET_SCSI_ID:
 980		{
 981			sg_scsi_id_t v;
 
 
 982
 983			if (atomic_read(&sdp->detaching))
 984				return -ENODEV;
 985			memset(&v, 0, sizeof(v));
 986			v.host_no = sdp->device->host->host_no;
 987			v.channel = sdp->device->channel;
 988			v.scsi_id = sdp->device->id;
 989			v.lun = sdp->device->lun;
 990			v.scsi_type = sdp->device->type;
 991			v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
 992			v.d_queue_depth = sdp->device->queue_depth;
 993			if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
 994				return -EFAULT;
 
 
 
 995			return 0;
 996		}
 997	case SG_SET_FORCE_PACK_ID:
 998		result = get_user(val, ip);
 999		if (result)
1000			return result;
1001		sfp->force_packid = val ? 1 : 0;
1002		return 0;
1003	case SG_GET_PACK_ID:
 
 
1004		read_lock_irqsave(&sfp->rq_list_lock, iflags);
1005		list_for_each_entry(srp, &sfp->rq_list, entry) {
1006			if ((1 == srp->done) && (!srp->sg_io_owned)) {
1007				read_unlock_irqrestore(&sfp->rq_list_lock,
1008						       iflags);
1009				return put_user(srp->header.pack_id, ip);
 
1010			}
1011		}
1012		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1013		return put_user(-1, ip);
 
1014	case SG_GET_NUM_WAITING:
1015		read_lock_irqsave(&sfp->rq_list_lock, iflags);
1016		val = 0;
1017		list_for_each_entry(srp, &sfp->rq_list, entry) {
1018			if ((1 == srp->done) && (!srp->sg_io_owned))
1019				++val;
1020		}
1021		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1022		return put_user(val, ip);
1023	case SG_GET_SG_TABLESIZE:
1024		return put_user(sdp->sg_tablesize, ip);
1025	case SG_SET_RESERVED_SIZE:
1026		result = get_user(val, ip);
1027		if (result)
1028			return result;
1029                if (val < 0)
1030                        return -EINVAL;
1031		val = min_t(int, val,
1032			    max_sectors_bytes(sdp->device->request_queue));
1033		mutex_lock(&sfp->f_mutex);
1034		if (val != sfp->reserve.bufflen) {
1035			if (sfp->mmap_called ||
1036			    sfp->res_in_use) {
1037				mutex_unlock(&sfp->f_mutex);
1038				return -EBUSY;
1039			}
1040
1041			sg_remove_scat(sfp, &sfp->reserve);
1042			sg_build_reserve(sfp, val);
1043		}
1044		mutex_unlock(&sfp->f_mutex);
1045		return 0;
1046	case SG_GET_RESERVED_SIZE:
1047		val = min_t(int, sfp->reserve.bufflen,
1048			    max_sectors_bytes(sdp->device->request_queue));
1049		return put_user(val, ip);
1050	case SG_SET_COMMAND_Q:
1051		result = get_user(val, ip);
1052		if (result)
1053			return result;
1054		sfp->cmd_q = val ? 1 : 0;
1055		return 0;
1056	case SG_GET_COMMAND_Q:
1057		return put_user((int) sfp->cmd_q, ip);
1058	case SG_SET_KEEP_ORPHAN:
1059		result = get_user(val, ip);
1060		if (result)
1061			return result;
1062		sfp->keep_orphan = val;
1063		return 0;
1064	case SG_GET_KEEP_ORPHAN:
1065		return put_user((int) sfp->keep_orphan, ip);
1066	case SG_NEXT_CMD_LEN:
1067		result = get_user(val, ip);
1068		if (result)
1069			return result;
1070		if (val > SG_MAX_CDB_SIZE)
1071			return -ENOMEM;
1072		sfp->next_cmd_len = (val > 0) ? val : 0;
1073		return 0;
1074	case SG_GET_VERSION_NUM:
1075		return put_user(sg_version_num, ip);
1076	case SG_GET_ACCESS_COUNT:
1077		/* faked - we don't have a real access count anymore */
1078		val = (sdp->device ? 1 : 0);
1079		return put_user(val, ip);
1080	case SG_GET_REQUEST_TABLE:
1081		{
 
 
1082			sg_req_info_t *rinfo;
 
1083
1084			rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1085					GFP_KERNEL);
1086			if (!rinfo)
1087				return -ENOMEM;
1088			read_lock_irqsave(&sfp->rq_list_lock, iflags);
1089			sg_fill_request_table(sfp, rinfo);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1090			read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1091	#ifdef CONFIG_COMPAT
1092			if (in_compat_syscall())
1093				result = put_compat_request_table(p, rinfo);
1094			else
1095	#endif
1096				result = copy_to_user(p, rinfo,
1097						      SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1098			result = result ? -EFAULT : 0;
1099			kfree(rinfo);
1100			return result;
1101		}
1102	case SG_EMULATED_HOST:
1103		if (atomic_read(&sdp->detaching))
1104			return -ENODEV;
1105		return put_user(sdp->device->host->hostt->emulated, ip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1106	case SCSI_IOCTL_SEND_COMMAND:
1107		if (atomic_read(&sdp->detaching))
1108			return -ENODEV;
 
 
 
 
 
 
 
 
 
1109		return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1110	case SG_SET_DEBUG:
1111		result = get_user(val, ip);
1112		if (result)
1113			return result;
1114		sdp->sgdebug = (char) val;
1115		return 0;
 
 
 
 
 
 
 
1116	case BLKSECTGET:
1117		return put_user(max_sectors_bytes(sdp->device->request_queue),
1118				ip);
1119	case BLKTRACESETUP:
1120		return blk_trace_setup(sdp->device->request_queue,
1121				       sdp->disk->disk_name,
1122				       MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1123				       NULL, p);
 
1124	case BLKTRACESTART:
1125		return blk_trace_startstop(sdp->device->request_queue, 1);
1126	case BLKTRACESTOP:
1127		return blk_trace_startstop(sdp->device->request_queue, 0);
1128	case BLKTRACETEARDOWN:
1129		return blk_trace_remove(sdp->device->request_queue);
1130	case SCSI_IOCTL_GET_IDLUN:
1131	case SCSI_IOCTL_GET_BUS_NUMBER:
1132	case SCSI_IOCTL_PROBE_HOST:
1133	case SG_GET_TRANSFORM:
1134	case SG_SCSI_RESET:
1135		if (atomic_read(&sdp->detaching))
1136			return -ENODEV;
1137		break;
1138	default:
1139		if (read_only)
1140			return -EPERM;	/* don't know so take safe approach */
1141		break;
1142	}
1143
1144	result = scsi_ioctl_block_when_processing_errors(sdp->device,
1145			cmd_in, filp->f_flags & O_NDELAY);
1146	if (result)
1147		return result;
1148
1149	return -ENOIOCTLCMD;
1150}
1151
1152static long
1153sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1154{
1155	void __user *p = (void __user *)arg;
1156	Sg_device *sdp;
1157	Sg_fd *sfp;
1158	int ret;
1159
1160	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1161		return -ENXIO;
 
1162
1163	ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1164	if (ret != -ENOIOCTLCMD)
1165		return ret;
1166
1167	return scsi_ioctl(sdp->device, cmd_in, p);
1168}
1169
1170#ifdef CONFIG_COMPAT
1171static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1172{
1173	void __user *p = compat_ptr(arg);
1174	Sg_device *sdp;
1175	Sg_fd *sfp;
1176	int ret;
1177
1178	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1179		return -ENXIO;
1180
1181	ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1182	if (ret != -ENOIOCTLCMD)
 
 
 
 
1183		return ret;
1184
1185	return scsi_compat_ioctl(sdp->device, cmd_in, p);
 
1186}
1187#endif
1188
1189static __poll_t
1190sg_poll(struct file *filp, poll_table * wait)
1191{
1192	__poll_t res = 0;
1193	Sg_device *sdp;
1194	Sg_fd *sfp;
1195	Sg_request *srp;
1196	int count = 0;
1197	unsigned long iflags;
1198
1199	sfp = filp->private_data;
1200	if (!sfp)
1201		return EPOLLERR;
1202	sdp = sfp->parentdp;
1203	if (!sdp)
1204		return EPOLLERR;
1205	poll_wait(filp, &sfp->read_wait, wait);
1206	read_lock_irqsave(&sfp->rq_list_lock, iflags);
1207	list_for_each_entry(srp, &sfp->rq_list, entry) {
1208		/* if any read waiting, flag it */
1209		if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1210			res = EPOLLIN | EPOLLRDNORM;
1211		++count;
1212	}
1213	read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1214
1215	if (atomic_read(&sdp->detaching))
1216		res |= EPOLLHUP;
1217	else if (!sfp->cmd_q) {
1218		if (0 == count)
1219			res |= EPOLLOUT | EPOLLWRNORM;
1220	} else if (count < SG_MAX_QUEUE)
1221		res |= EPOLLOUT | EPOLLWRNORM;
1222	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1223				      "sg_poll: res=0x%x\n", (__force u32) res));
1224	return res;
1225}
1226
1227static int
1228sg_fasync(int fd, struct file *filp, int mode)
1229{
1230	Sg_device *sdp;
1231	Sg_fd *sfp;
1232
1233	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1234		return -ENXIO;
1235	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1236				      "sg_fasync: mode=%d\n", mode));
1237
1238	return fasync_helper(fd, filp, mode, &sfp->async_qp);
1239}
1240
1241static vm_fault_t
1242sg_vma_fault(struct vm_fault *vmf)
1243{
1244	struct vm_area_struct *vma = vmf->vma;
1245	Sg_fd *sfp;
1246	unsigned long offset, len, sa;
1247	Sg_scatter_hold *rsv_schp;
1248	int k, length;
1249
1250	if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1251		return VM_FAULT_SIGBUS;
1252	rsv_schp = &sfp->reserve;
1253	offset = vmf->pgoff << PAGE_SHIFT;
1254	if (offset >= rsv_schp->bufflen)
1255		return VM_FAULT_SIGBUS;
1256	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1257				      "sg_vma_fault: offset=%lu, scatg=%d\n",
1258				      offset, rsv_schp->k_use_sg));
1259	sa = vma->vm_start;
1260	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1261	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1262		len = vma->vm_end - sa;
1263		len = (len < length) ? len : length;
1264		if (offset < len) {
1265			struct page *page = nth_page(rsv_schp->pages[k],
1266						     offset >> PAGE_SHIFT);
1267			get_page(page);	/* increment page count */
1268			vmf->page = page;
1269			return 0; /* success */
1270		}
1271		sa += len;
1272		offset -= len;
1273	}
1274
1275	return VM_FAULT_SIGBUS;
1276}
1277
1278static const struct vm_operations_struct sg_mmap_vm_ops = {
1279	.fault = sg_vma_fault,
1280};
1281
1282static int
1283sg_mmap(struct file *filp, struct vm_area_struct *vma)
1284{
1285	Sg_fd *sfp;
1286	unsigned long req_sz, len, sa;
1287	Sg_scatter_hold *rsv_schp;
1288	int k, length;
1289	int ret = 0;
1290
1291	if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1292		return -ENXIO;
1293	req_sz = vma->vm_end - vma->vm_start;
1294	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1295				      "sg_mmap starting, vm_start=%p, len=%d\n",
1296				      (void *) vma->vm_start, (int) req_sz));
1297	if (vma->vm_pgoff)
1298		return -EINVAL;	/* want no offset */
1299	rsv_schp = &sfp->reserve;
1300	mutex_lock(&sfp->f_mutex);
1301	if (req_sz > rsv_schp->bufflen) {
1302		ret = -ENOMEM;	/* cannot map more than reserved buffer */
1303		goto out;
1304	}
1305
1306	sa = vma->vm_start;
1307	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1308	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1309		len = vma->vm_end - sa;
1310		len = (len < length) ? len : length;
1311		sa += len;
1312	}
1313
1314	sfp->mmap_called = 1;
1315	vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1316	vma->vm_private_data = sfp;
1317	vma->vm_ops = &sg_mmap_vm_ops;
1318out:
1319	mutex_unlock(&sfp->f_mutex);
1320	return ret;
1321}
1322
1323static void
1324sg_rq_end_io_usercontext(struct work_struct *work)
1325{
1326	struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1327	struct sg_fd *sfp = srp->parentfp;
1328
1329	sg_finish_rem_req(srp);
1330	sg_remove_request(sfp, srp);
1331	kref_put(&sfp->f_ref, sg_remove_sfp);
1332}
1333
1334/*
1335 * This function is a "bottom half" handler that is called by the mid
1336 * level when a command is completed (or has failed).
1337 */
1338static void
1339sg_rq_end_io(struct request *rq, blk_status_t status)
1340{
1341	struct sg_request *srp = rq->end_io_data;
1342	struct scsi_request *req = scsi_req(rq);
1343	Sg_device *sdp;
1344	Sg_fd *sfp;
1345	unsigned long iflags;
1346	unsigned int ms;
1347	char *sense;
1348	int result, resid, done = 1;
1349
1350	if (WARN_ON(srp->done != 0))
1351		return;
1352
1353	sfp = srp->parentfp;
1354	if (WARN_ON(sfp == NULL))
1355		return;
1356
1357	sdp = sfp->parentdp;
1358	if (unlikely(atomic_read(&sdp->detaching)))
1359		pr_info("%s: device detaching\n", __func__);
 
 
 
 
1360
1361	sense = req->sense;
1362	result = req->result;
1363	resid = req->resid_len;
1364
1365	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1366				      "sg_cmd_done: pack_id=%d, res=0x%x\n",
1367				      srp->header.pack_id, result));
1368	srp->header.resid = resid;
1369	ms = jiffies_to_msecs(jiffies);
1370	srp->header.duration = (ms > srp->header.duration) ?
1371				(ms - srp->header.duration) : 0;
1372	if (0 != result) {
1373		struct scsi_sense_hdr sshdr;
1374
1375		srp->header.status = 0xff & result;
1376		srp->header.masked_status = status_byte(result);
1377		srp->header.msg_status = msg_byte(result);
1378		srp->header.host_status = host_byte(result);
1379		srp->header.driver_status = driver_byte(result);
1380		if ((sdp->sgdebug > 0) &&
1381		    ((CHECK_CONDITION == srp->header.masked_status) ||
1382		     (COMMAND_TERMINATED == srp->header.masked_status)))
1383			__scsi_print_sense(sdp->device, __func__, sense,
1384					   SCSI_SENSE_BUFFERSIZE);
1385
1386		/* Following if statement is a patch supplied by Eric Youngdale */
1387		if (driver_byte(result) != 0
1388		    && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1389		    && !scsi_sense_is_deferred(&sshdr)
1390		    && sshdr.sense_key == UNIT_ATTENTION
1391		    && sdp->device->removable) {
1392			/* Detected possible disc change. Set the bit - this */
1393			/* may be used if there are filesystems using this device */
1394			sdp->device->changed = 1;
1395		}
1396	}
1397
1398	if (req->sense_len)
1399		memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1400
1401	/* Rely on write phase to clean out srp status values, so no "else" */
1402
1403	/*
1404	 * Free the request as soon as it is complete so that its resources
1405	 * can be reused without waiting for userspace to read() the
1406	 * result.  But keep the associated bio (if any) around until
1407	 * blk_rq_unmap_user() can be called from user context.
1408	 */
1409	srp->rq = NULL;
1410	scsi_req_free_cmd(scsi_req(rq));
1411	blk_put_request(rq);
1412
1413	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1414	if (unlikely(srp->orphan)) {
1415		if (sfp->keep_orphan)
1416			srp->sg_io_owned = 0;
1417		else
1418			done = 0;
1419	}
1420	srp->done = done;
1421	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1422
1423	if (likely(done)) {
1424		/* Now wake up any sg_read() that is waiting for this
1425		 * packet.
1426		 */
1427		wake_up_interruptible(&sfp->read_wait);
1428		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1429		kref_put(&sfp->f_ref, sg_remove_sfp);
1430	} else {
1431		INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1432		schedule_work(&srp->ew.work);
1433	}
1434}
1435
1436static const struct file_operations sg_fops = {
1437	.owner = THIS_MODULE,
1438	.read = sg_read,
1439	.write = sg_write,
1440	.poll = sg_poll,
1441	.unlocked_ioctl = sg_ioctl,
1442#ifdef CONFIG_COMPAT
1443	.compat_ioctl = sg_compat_ioctl,
1444#endif
1445	.open = sg_open,
1446	.mmap = sg_mmap,
1447	.release = sg_release,
1448	.fasync = sg_fasync,
1449	.llseek = no_llseek,
1450};
1451
1452static struct class *sg_sysfs_class;
1453
1454static int sg_sysfs_valid = 0;
1455
1456static Sg_device *
1457sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1458{
1459	struct request_queue *q = scsidp->request_queue;
1460	Sg_device *sdp;
1461	unsigned long iflags;
1462	int error;
1463	u32 k;
1464
1465	sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1466	if (!sdp) {
1467		sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1468			    "failure\n", __func__);
1469		return ERR_PTR(-ENOMEM);
1470	}
1471
1472	idr_preload(GFP_KERNEL);
 
 
 
 
 
1473	write_lock_irqsave(&sg_index_lock, iflags);
1474
1475	error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1476	if (error < 0) {
1477		if (error == -ENOSPC) {
1478			sdev_printk(KERN_WARNING, scsidp,
1479				    "Unable to attach sg device type=%d, minor number exceeds %d\n",
1480				    scsidp->type, SG_MAX_DEVS - 1);
1481			error = -ENODEV;
1482		} else {
1483			sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1484				    "allocation Sg_device failure: %d\n",
1485				    __func__, error);
1486		}
1487		goto out_unlock;
1488	}
1489	k = error;
1490
1491	SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1492					"sg_alloc: dev=%d \n", k));
 
 
1493	sprintf(disk->disk_name, "sg%d", k);
1494	disk->first_minor = k;
1495	sdp->disk = disk;
1496	sdp->device = scsidp;
1497	mutex_init(&sdp->open_rel_lock);
1498	INIT_LIST_HEAD(&sdp->sfds);
1499	init_waitqueue_head(&sdp->open_wait);
1500	atomic_set(&sdp->detaching, 0);
1501	rwlock_init(&sdp->sfd_lock);
1502	sdp->sg_tablesize = queue_max_segments(q);
1503	sdp->index = k;
1504	kref_init(&sdp->d_ref);
1505	error = 0;
1506
1507out_unlock:
1508	write_unlock_irqrestore(&sg_index_lock, iflags);
1509	idr_preload_end();
1510
 
 
1511	if (error) {
1512		kfree(sdp);
1513		return ERR_PTR(error);
1514	}
1515	return sdp;
 
 
 
 
 
 
 
 
 
1516}
1517
1518static int
1519sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1520{
1521	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1522	struct gendisk *disk;
1523	Sg_device *sdp = NULL;
1524	struct cdev * cdev = NULL;
1525	int error;
1526	unsigned long iflags;
1527
1528	disk = alloc_disk(1);
1529	if (!disk) {
1530		pr_warn("%s: alloc_disk failed\n", __func__);
1531		return -ENOMEM;
1532	}
1533	disk->major = SCSI_GENERIC_MAJOR;
1534
1535	error = -ENOMEM;
1536	cdev = cdev_alloc();
1537	if (!cdev) {
1538		pr_warn("%s: cdev_alloc failed\n", __func__);
1539		goto out;
1540	}
1541	cdev->owner = THIS_MODULE;
1542	cdev->ops = &sg_fops;
1543
1544	sdp = sg_alloc(disk, scsidp);
1545	if (IS_ERR(sdp)) {
1546		pr_warn("%s: sg_alloc failed\n", __func__);
1547		error = PTR_ERR(sdp);
1548		goto out;
1549	}
1550
1551	error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1552	if (error)
1553		goto cdev_add_err;
1554
1555	sdp->cdev = cdev;
1556	if (sg_sysfs_valid) {
1557		struct device *sg_class_member;
1558
1559		sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1560						MKDEV(SCSI_GENERIC_MAJOR,
1561						      sdp->index),
1562						sdp, "%s", disk->disk_name);
1563		if (IS_ERR(sg_class_member)) {
1564			pr_err("%s: device_create failed\n", __func__);
 
1565			error = PTR_ERR(sg_class_member);
1566			goto cdev_add_err;
1567		}
1568		error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1569					  &sg_class_member->kobj, "generic");
1570		if (error)
1571			pr_err("%s: unable to make symlink 'generic' back "
1572			       "to sg%d\n", __func__, sdp->index);
1573	} else
1574		pr_warn("%s: sg_sys Invalid\n", __func__);
1575
1576	sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1577		    "type %d\n", sdp->index, scsidp->type);
 
1578
1579	dev_set_drvdata(cl_dev, sdp);
1580
1581	return 0;
1582
1583cdev_add_err:
1584	write_lock_irqsave(&sg_index_lock, iflags);
1585	idr_remove(&sg_index_idr, sdp->index);
1586	write_unlock_irqrestore(&sg_index_lock, iflags);
1587	kfree(sdp);
1588
1589out:
1590	put_disk(disk);
1591	if (cdev)
1592		cdev_del(cdev);
1593	return error;
1594}
1595
1596static void
1597sg_device_destroy(struct kref *kref)
1598{
1599	struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1600	unsigned long flags;
1601
1602	/* CAUTION!  Note that the device can still be found via idr_find()
1603	 * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1604	 * any other cleanup.
1605	 */
1606
1607	write_lock_irqsave(&sg_index_lock, flags);
1608	idr_remove(&sg_index_idr, sdp->index);
1609	write_unlock_irqrestore(&sg_index_lock, flags);
1610
1611	SCSI_LOG_TIMEOUT(3,
1612		sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
 
1613
1614	put_disk(sdp->disk);
1615	kfree(sdp);
1616}
1617
1618static void
1619sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1620{
1621	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1622	Sg_device *sdp = dev_get_drvdata(cl_dev);
1623	unsigned long iflags;
1624	Sg_fd *sfp;
1625	int val;
1626
1627	if (!sdp)
1628		return;
1629	/* want sdp->detaching non-zero as soon as possible */
1630	val = atomic_inc_return(&sdp->detaching);
1631	if (val > 1)
1632		return; /* only want to do following once per device */
1633
1634	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1635				      "%s\n", __func__));
1636
1637	read_lock_irqsave(&sdp->sfd_lock, iflags);
 
 
1638	list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1639		wake_up_interruptible_all(&sfp->read_wait);
1640		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1641	}
1642	wake_up_interruptible_all(&sdp->open_wait);
1643	read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1644
1645	sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1646	device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1647	cdev_del(sdp->cdev);
1648	sdp->cdev = NULL;
1649
1650	kref_put(&sdp->d_ref, sg_device_destroy);
1651}
1652
1653module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1654module_param_named(def_reserved_size, def_reserved_size, int,
1655		   S_IRUGO | S_IWUSR);
1656module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1657
1658MODULE_AUTHOR("Douglas Gilbert");
1659MODULE_DESCRIPTION("SCSI generic (sg) driver");
1660MODULE_LICENSE("GPL");
1661MODULE_VERSION(SG_VERSION_STR);
1662MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1663
1664MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1665                "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1666MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1667MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1668
1669static int __init
1670init_sg(void)
1671{
1672	int rc;
1673
1674	if (scatter_elem_sz < PAGE_SIZE) {
1675		scatter_elem_sz = PAGE_SIZE;
1676		scatter_elem_sz_prev = scatter_elem_sz;
1677	}
1678	if (def_reserved_size >= 0)
1679		sg_big_buff = def_reserved_size;
1680	else
1681		def_reserved_size = sg_big_buff;
1682
1683	rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 
1684				    SG_MAX_DEVS, "sg");
1685	if (rc)
1686		return rc;
1687        sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1688        if ( IS_ERR(sg_sysfs_class) ) {
1689		rc = PTR_ERR(sg_sysfs_class);
1690		goto err_out;
1691        }
1692	sg_sysfs_valid = 1;
1693	rc = scsi_register_interface(&sg_interface);
1694	if (0 == rc) {
1695#ifdef CONFIG_SCSI_PROC_FS
1696		sg_proc_init();
1697#endif				/* CONFIG_SCSI_PROC_FS */
1698		return 0;
1699	}
1700	class_destroy(sg_sysfs_class);
1701err_out:
1702	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1703	return rc;
1704}
1705
1706static void __exit
1707exit_sg(void)
1708{
1709#ifdef CONFIG_SCSI_PROC_FS
1710	remove_proc_subtree("scsi/sg", NULL);
1711#endif				/* CONFIG_SCSI_PROC_FS */
1712	scsi_unregister_interface(&sg_interface);
1713	class_destroy(sg_sysfs_class);
1714	sg_sysfs_valid = 0;
1715	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1716				 SG_MAX_DEVS);
1717	idr_destroy(&sg_index_idr);
1718}
1719
1720static int
1721sg_start_req(Sg_request *srp, unsigned char *cmd)
1722{
1723	int res;
1724	struct request *rq;
1725	struct scsi_request *req;
1726	Sg_fd *sfp = srp->parentfp;
1727	sg_io_hdr_t *hp = &srp->header;
1728	int dxfer_len = (int) hp->dxfer_len;
1729	int dxfer_dir = hp->dxfer_direction;
1730	unsigned int iov_count = hp->iovec_count;
1731	Sg_scatter_hold *req_schp = &srp->data;
1732	Sg_scatter_hold *rsv_schp = &sfp->reserve;
1733	struct request_queue *q = sfp->parentdp->device->request_queue;
1734	struct rq_map_data *md, map_data;
1735	int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1736	unsigned char *long_cmdp = NULL;
1737
1738	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1739				      "sg_start_req: dxfer_len=%d\n",
1740				      dxfer_len));
1741
1742	if (hp->cmd_len > BLK_MAX_CDB) {
1743		long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1744		if (!long_cmdp)
1745			return -ENOMEM;
1746	}
1747
1748	/*
1749	 * NOTE
1750	 *
1751	 * With scsi-mq enabled, there are a fixed number of preallocated
1752	 * requests equal in number to shost->can_queue.  If all of the
1753	 * preallocated requests are already in use, then blk_get_request()
1754	 * will sleep until an active command completes, freeing up a request.
1755	 * Although waiting in an asynchronous interface is less than ideal, we
1756	 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1757	 * not expect an EWOULDBLOCK from this condition.
1758	 */
1759	rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1760			REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
1761	if (IS_ERR(rq)) {
1762		kfree(long_cmdp);
1763		return PTR_ERR(rq);
1764	}
1765	req = scsi_req(rq);
1766
1767	if (hp->cmd_len > BLK_MAX_CDB)
1768		req->cmd = long_cmdp;
1769	memcpy(req->cmd, cmd, hp->cmd_len);
1770	req->cmd_len = hp->cmd_len;
1771
1772	srp->rq = rq;
1773	rq->end_io_data = srp;
1774	req->retries = SG_DEFAULT_RETRIES;
 
1775
1776	if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1777		return 0;
1778
1779	if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1780	    dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1781	    !sfp->parentdp->device->host->unchecked_isa_dma &&
1782	    blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1783		md = NULL;
1784	else
1785		md = &map_data;
1786
1787	if (md) {
1788		mutex_lock(&sfp->f_mutex);
1789		if (dxfer_len <= rsv_schp->bufflen &&
1790		    !sfp->res_in_use) {
1791			sfp->res_in_use = 1;
1792			sg_link_reserve(sfp, srp, dxfer_len);
1793		} else if (hp->flags & SG_FLAG_MMAP_IO) {
1794			res = -EBUSY; /* sfp->res_in_use == 1 */
1795			if (dxfer_len > rsv_schp->bufflen)
1796				res = -ENOMEM;
1797			mutex_unlock(&sfp->f_mutex);
1798			return res;
1799		} else {
1800			res = sg_build_indirect(req_schp, sfp, dxfer_len);
1801			if (res) {
1802				mutex_unlock(&sfp->f_mutex);
1803				return res;
1804			}
1805		}
1806		mutex_unlock(&sfp->f_mutex);
1807
1808		md->pages = req_schp->pages;
1809		md->page_order = req_schp->page_order;
1810		md->nr_entries = req_schp->k_use_sg;
1811		md->offset = 0;
1812		md->null_mapped = hp->dxferp ? 0 : 1;
1813		if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1814			md->from_user = 1;
1815		else
1816			md->from_user = 0;
1817	}
1818
1819	if (iov_count) {
1820		struct iovec *iov = NULL;
1821		struct iov_iter i;
1822
1823#ifdef CONFIG_COMPAT
1824		if (in_compat_syscall())
1825			res = compat_import_iovec(rw, hp->dxferp, iov_count,
1826						  0, &iov, &i);
1827		else
1828#endif
1829			res = import_iovec(rw, hp->dxferp, iov_count,
1830					   0, &iov, &i);
1831		if (res < 0)
1832			return res;
1833
1834		iov_iter_truncate(&i, hp->dxfer_len);
1835		if (!iov_iter_count(&i)) {
1836			kfree(iov);
1837			return -EINVAL;
1838		}
1839
1840		res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1841		kfree(iov);
1842	} else
1843		res = blk_rq_map_user(q, rq, md, hp->dxferp,
1844				      hp->dxfer_len, GFP_ATOMIC);
1845
1846	if (!res) {
1847		srp->bio = rq->bio;
1848
1849		if (!md) {
1850			req_schp->dio_in_use = 1;
1851			hp->info |= SG_INFO_DIRECT_IO;
1852		}
1853	}
1854	return res;
1855}
1856
1857static int
1858sg_finish_rem_req(Sg_request *srp)
1859{
1860	int ret = 0;
1861
1862	Sg_fd *sfp = srp->parentfp;
1863	Sg_scatter_hold *req_schp = &srp->data;
1864
1865	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1866				      "sg_finish_rem_req: res_used=%d\n",
1867				      (int) srp->res_used));
1868	if (srp->bio)
1869		ret = blk_rq_unmap_user(srp->bio);
1870
1871	if (srp->rq) {
1872		scsi_req_free_cmd(scsi_req(srp->rq));
1873		blk_put_request(srp->rq);
1874	}
1875
1876	if (srp->res_used)
1877		sg_unlink_reserve(sfp, srp);
1878	else
1879		sg_remove_scat(sfp, req_schp);
 
 
1880
1881	return ret;
1882}
1883
1884static int
1885sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1886{
1887	int sg_bufflen = tablesize * sizeof(struct page *);
1888	gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1889
1890	schp->pages = kzalloc(sg_bufflen, gfp_flags);
1891	if (!schp->pages)
1892		return -ENOMEM;
1893	schp->sglist_len = sg_bufflen;
1894	return tablesize;	/* number of scat_gath elements allocated */
1895}
1896
1897static int
1898sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1899{
1900	int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1901	int sg_tablesize = sfp->parentdp->sg_tablesize;
1902	int blk_size = buff_size, order;
1903	gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1904	struct sg_device *sdp = sfp->parentdp;
1905
1906	if (blk_size < 0)
1907		return -EFAULT;
1908	if (0 == blk_size)
1909		++blk_size;	/* don't know why */
1910	/* round request up to next highest SG_SECTOR_SZ byte boundary */
1911	blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1912	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1913		"sg_build_indirect: buff_size=%d, blk_size=%d\n",
1914		buff_size, blk_size));
1915
1916	/* N.B. ret_sz carried into this block ... */
1917	mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1918	if (mx_sc_elems < 0)
1919		return mx_sc_elems;	/* most likely -ENOMEM */
1920
1921	num = scatter_elem_sz;
1922	if (unlikely(num != scatter_elem_sz_prev)) {
1923		if (num < PAGE_SIZE) {
1924			scatter_elem_sz = PAGE_SIZE;
1925			scatter_elem_sz_prev = PAGE_SIZE;
1926		} else
1927			scatter_elem_sz_prev = num;
1928	}
1929
1930	if (sdp->device->host->unchecked_isa_dma)
1931		gfp_mask |= GFP_DMA;
1932
 
 
 
1933	order = get_order(num);
1934retry:
1935	ret_sz = 1 << (PAGE_SHIFT + order);
1936
1937	for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1938	     k++, rem_sz -= ret_sz) {
1939
1940		num = (rem_sz > scatter_elem_sz_prev) ?
1941			scatter_elem_sz_prev : rem_sz;
1942
1943		schp->pages[k] = alloc_pages(gfp_mask, order);
1944		if (!schp->pages[k])
1945			goto out;
1946
1947		if (num == scatter_elem_sz_prev) {
1948			if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1949				scatter_elem_sz = ret_sz;
1950				scatter_elem_sz_prev = ret_sz;
1951			}
1952		}
1953
1954		SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1955				 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1956				 k, num, ret_sz));
1957	}		/* end of for loop */
1958
1959	schp->page_order = order;
1960	schp->k_use_sg = k;
1961	SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1962			 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1963			 k, rem_sz));
1964
1965	schp->bufflen = blk_size;
1966	if (rem_sz > 0)	/* must have failed */
1967		return -ENOMEM;
1968	return 0;
1969out:
1970	for (i = 0; i < k; i++)
1971		__free_pages(schp->pages[i], order);
1972
1973	if (--order >= 0)
1974		goto retry;
1975
1976	return -ENOMEM;
1977}
1978
1979static void
1980sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1981{
1982	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1983			 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1984	if (schp->pages && schp->sglist_len > 0) {
1985		if (!schp->dio_in_use) {
1986			int k;
1987
1988			for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1989				SCSI_LOG_TIMEOUT(5,
1990					sg_printk(KERN_INFO, sfp->parentdp,
1991					"sg_remove_scat: k=%d, pg=0x%p\n",
1992					k, schp->pages[k]));
1993				__free_pages(schp->pages[k], schp->page_order);
1994			}
1995
1996			kfree(schp->pages);
1997		}
1998	}
1999	memset(schp, 0, sizeof (*schp));
2000}
2001
2002static int
2003sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2004{
2005	Sg_scatter_hold *schp = &srp->data;
2006	int k, num;
2007
2008	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2009			 "sg_read_oxfer: num_read_xfer=%d\n",
2010			 num_read_xfer));
2011	if ((!outp) || (num_read_xfer <= 0))
2012		return 0;
2013
2014	num = 1 << (PAGE_SHIFT + schp->page_order);
2015	for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
2016		if (num > num_read_xfer) {
2017			if (copy_to_user(outp, page_address(schp->pages[k]),
2018					   num_read_xfer))
2019				return -EFAULT;
2020			break;
2021		} else {
2022			if (copy_to_user(outp, page_address(schp->pages[k]),
2023					   num))
2024				return -EFAULT;
2025			num_read_xfer -= num;
2026			if (num_read_xfer <= 0)
2027				break;
2028			outp += num;
2029		}
2030	}
2031
2032	return 0;
2033}
2034
2035static void
2036sg_build_reserve(Sg_fd * sfp, int req_size)
2037{
2038	Sg_scatter_hold *schp = &sfp->reserve;
2039
2040	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2041			 "sg_build_reserve: req_size=%d\n", req_size));
2042	do {
2043		if (req_size < PAGE_SIZE)
2044			req_size = PAGE_SIZE;
2045		if (0 == sg_build_indirect(schp, sfp, req_size))
2046			return;
2047		else
2048			sg_remove_scat(sfp, schp);
2049		req_size >>= 1;	/* divide by 2 */
2050	} while (req_size > (PAGE_SIZE / 2));
2051}
2052
2053static void
2054sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2055{
2056	Sg_scatter_hold *req_schp = &srp->data;
2057	Sg_scatter_hold *rsv_schp = &sfp->reserve;
2058	int k, num, rem;
2059
2060	srp->res_used = 1;
2061	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2062			 "sg_link_reserve: size=%d\n", size));
2063	rem = size;
2064
2065	num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2066	for (k = 0; k < rsv_schp->k_use_sg; k++) {
2067		if (rem <= num) {
2068			req_schp->k_use_sg = k + 1;
2069			req_schp->sglist_len = rsv_schp->sglist_len;
2070			req_schp->pages = rsv_schp->pages;
2071
2072			req_schp->bufflen = size;
2073			req_schp->page_order = rsv_schp->page_order;
2074			break;
2075		} else
2076			rem -= num;
2077	}
2078
2079	if (k >= rsv_schp->k_use_sg)
2080		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2081				 "sg_link_reserve: BAD size\n"));
2082}
2083
2084static void
2085sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2086{
2087	Sg_scatter_hold *req_schp = &srp->data;
2088
2089	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2090				      "sg_unlink_reserve: req->k_use_sg=%d\n",
2091				      (int) req_schp->k_use_sg));
2092	req_schp->k_use_sg = 0;
2093	req_schp->bufflen = 0;
2094	req_schp->pages = NULL;
2095	req_schp->page_order = 0;
2096	req_schp->sglist_len = 0;
 
2097	srp->res_used = 0;
2098	/* Called without mutex lock to avoid deadlock */
2099	sfp->res_in_use = 0;
2100}
2101
2102static Sg_request *
2103sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2104{
2105	Sg_request *resp;
2106	unsigned long iflags;
2107
2108	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2109	list_for_each_entry(resp, &sfp->rq_list, entry) {
2110		/* look for requests that are ready + not SG_IO owned */
2111		if ((1 == resp->done) && (!resp->sg_io_owned) &&
2112		    ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2113			resp->done = 2;	/* guard against other readers */
2114			write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2115			return resp;
2116		}
2117	}
2118	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2119	return NULL;
2120}
2121
2122/* always adds to end of list */
2123static Sg_request *
2124sg_add_request(Sg_fd * sfp)
2125{
2126	int k;
2127	unsigned long iflags;
 
2128	Sg_request *rp = sfp->req_arr;
2129
2130	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2131	if (!list_empty(&sfp->rq_list)) {
2132		if (!sfp->cmd_q)
2133			goto out_unlock;
2134
2135		for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2136			if (!rp->parentfp)
2137				break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2138		}
2139		if (k >= SG_MAX_QUEUE)
2140			goto out_unlock;
2141	}
2142	memset(rp, 0, sizeof (Sg_request));
2143	rp->parentfp = sfp;
2144	rp->header.duration = jiffies_to_msecs(jiffies);
2145	list_add_tail(&rp->entry, &sfp->rq_list);
2146	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2147	return rp;
2148out_unlock:
2149	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2150	return NULL;
2151}
2152
2153/* Return of 1 for found; 0 for not found */
2154static int
2155sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2156{
 
 
2157	unsigned long iflags;
2158	int res = 0;
2159
2160	if (!sfp || !srp || list_empty(&sfp->rq_list))
2161		return res;
2162	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2163	if (!list_empty(&srp->entry)) {
2164		list_del(&srp->entry);
2165		srp->parentfp = NULL;
 
2166		res = 1;
 
 
 
 
 
 
 
 
 
 
2167	}
2168	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2169	return res;
2170}
2171
2172static Sg_fd *
2173sg_add_sfp(Sg_device * sdp)
2174{
2175	Sg_fd *sfp;
2176	unsigned long iflags;
2177	int bufflen;
2178
2179	sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2180	if (!sfp)
2181		return ERR_PTR(-ENOMEM);
2182
2183	init_waitqueue_head(&sfp->read_wait);
2184	rwlock_init(&sfp->rq_list_lock);
2185	INIT_LIST_HEAD(&sfp->rq_list);
2186	kref_init(&sfp->f_ref);
2187	mutex_init(&sfp->f_mutex);
2188	sfp->timeout = SG_DEFAULT_TIMEOUT;
2189	sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2190	sfp->force_packid = SG_DEF_FORCE_PACK_ID;
 
 
2191	sfp->cmd_q = SG_DEF_COMMAND_Q;
2192	sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2193	sfp->parentdp = sdp;
2194	write_lock_irqsave(&sdp->sfd_lock, iflags);
2195	if (atomic_read(&sdp->detaching)) {
2196		write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2197		kfree(sfp);
2198		return ERR_PTR(-ENODEV);
2199	}
2200	list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2201	write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2202	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2203				      "sg_add_sfp: sfp=0x%p\n", sfp));
2204	if (unlikely(sg_big_buff != def_reserved_size))
2205		sg_big_buff = def_reserved_size;
2206
2207	bufflen = min_t(int, sg_big_buff,
2208			max_sectors_bytes(sdp->device->request_queue));
2209	sg_build_reserve(sfp, bufflen);
2210	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2211				      "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2212				      sfp->reserve.bufflen,
2213				      sfp->reserve.k_use_sg));
2214
2215	kref_get(&sdp->d_ref);
2216	__module_get(THIS_MODULE);
2217	return sfp;
2218}
2219
2220static void
2221sg_remove_sfp_usercontext(struct work_struct *work)
2222{
2223	struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2224	struct sg_device *sdp = sfp->parentdp;
2225	Sg_request *srp;
2226	unsigned long iflags;
2227
2228	/* Cleanup any responses which were never read(). */
2229	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2230	while (!list_empty(&sfp->rq_list)) {
2231		srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2232		sg_finish_rem_req(srp);
2233		list_del(&srp->entry);
2234		srp->parentfp = NULL;
2235	}
2236	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2237
2238	if (sfp->reserve.bufflen > 0) {
2239		SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2240				"sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2241				(int) sfp->reserve.bufflen,
2242				(int) sfp->reserve.k_use_sg));
2243		sg_remove_scat(sfp, &sfp->reserve);
2244	}
2245
2246	SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2247			"sg_remove_sfp: sfp=0x%p\n", sfp));
 
 
2248	kfree(sfp);
2249
2250	scsi_device_put(sdp->device);
2251	kref_put(&sdp->d_ref, sg_device_destroy);
2252	module_put(THIS_MODULE);
2253}
2254
2255static void
2256sg_remove_sfp(struct kref *kref)
2257{
2258	struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2259	struct sg_device *sdp = sfp->parentdp;
2260	unsigned long iflags;
2261
2262	write_lock_irqsave(&sdp->sfd_lock, iflags);
2263	list_del(&sfp->sfd_siblings);
2264	write_unlock_irqrestore(&sdp->sfd_lock, iflags);
 
2265
2266	INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2267	schedule_work(&sfp->ew.work);
2268}
2269
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2270#ifdef CONFIG_SCSI_PROC_FS
2271static int
2272sg_idr_max_id(int id, void *p, void *data)
2273{
2274	int *k = data;
2275
2276	if (*k < id)
2277		*k = id;
2278
2279	return 0;
2280}
2281
2282static int
2283sg_last_dev(void)
2284{
2285	int k = -1;
2286	unsigned long iflags;
2287
2288	read_lock_irqsave(&sg_index_lock, iflags);
2289	idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2290	read_unlock_irqrestore(&sg_index_lock, iflags);
2291	return k + 1;		/* origin 1 */
2292}
2293#endif
2294
2295/* must be called with sg_index_lock held */
2296static Sg_device *sg_lookup_dev(int dev)
2297{
2298	return idr_find(&sg_index_idr, dev);
2299}
2300
2301static Sg_device *
2302sg_get_dev(int dev)
2303{
2304	struct sg_device *sdp;
2305	unsigned long flags;
2306
2307	read_lock_irqsave(&sg_index_lock, flags);
2308	sdp = sg_lookup_dev(dev);
2309	if (!sdp)
2310		sdp = ERR_PTR(-ENXIO);
2311	else if (atomic_read(&sdp->detaching)) {
2312		/* If sdp->detaching, then the refcount may already be 0, in
2313		 * which case it would be a bug to do kref_get().
2314		 */
2315		sdp = ERR_PTR(-ENODEV);
2316	} else
2317		kref_get(&sdp->d_ref);
2318	read_unlock_irqrestore(&sg_index_lock, flags);
2319
2320	return sdp;
2321}
2322
 
 
 
 
 
2323#ifdef CONFIG_SCSI_PROC_FS
 
 
 
 
 
2324static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2325
2326static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2327static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2328			          size_t count, loff_t *off);
2329static const struct proc_ops adio_proc_ops = {
2330	.proc_open	= sg_proc_single_open_adio,
2331	.proc_read	= seq_read,
2332	.proc_lseek	= seq_lseek,
2333	.proc_write	= sg_proc_write_adio,
2334	.proc_release	= single_release,
 
2335};
2336
2337static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2338static ssize_t sg_proc_write_dressz(struct file *filp, 
2339		const char __user *buffer, size_t count, loff_t *off);
2340static const struct proc_ops dressz_proc_ops = {
2341	.proc_open	= sg_proc_single_open_dressz,
2342	.proc_read	= seq_read,
2343	.proc_lseek	= seq_lseek,
2344	.proc_write	= sg_proc_write_dressz,
2345	.proc_release	= single_release,
 
2346};
2347
2348static int sg_proc_seq_show_version(struct seq_file *s, void *v);
 
 
 
 
 
 
 
 
 
2349static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
 
 
 
 
 
 
 
 
 
2350static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
 
2351static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2352static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2353static void dev_seq_stop(struct seq_file *s, void *v);
 
 
 
 
 
 
 
2354static const struct seq_operations dev_seq_ops = {
2355	.start = dev_seq_start,
2356	.next  = dev_seq_next,
2357	.stop  = dev_seq_stop,
2358	.show  = sg_proc_seq_show_dev,
2359};
2360
2361static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
 
 
 
 
 
 
 
 
2362static const struct seq_operations devstrs_seq_ops = {
2363	.start = dev_seq_start,
2364	.next  = dev_seq_next,
2365	.stop  = dev_seq_stop,
2366	.show  = sg_proc_seq_show_devstrs,
2367};
2368
2369static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
 
 
 
 
 
 
 
 
2370static const struct seq_operations debug_seq_ops = {
2371	.start = dev_seq_start,
2372	.next  = dev_seq_next,
2373	.stop  = dev_seq_stop,
2374	.show  = sg_proc_seq_show_debug,
2375};
2376
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2377static int
2378sg_proc_init(void)
2379{
2380	struct proc_dir_entry *p;
 
 
2381
2382	p = proc_mkdir("scsi/sg", NULL);
2383	if (!p)
2384		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
2385
2386	proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);
2387	proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2388	proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);
2389	proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2390	proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2391	proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2392	proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2393	return 0;
2394}
2395
2396
2397static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2398{
2399	seq_printf(s, "%d\n", *((int *)s->private));
2400	return 0;
2401}
2402
2403static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2404{
2405	return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2406}
2407
2408static ssize_t 
2409sg_proc_write_adio(struct file *filp, const char __user *buffer,
2410		   size_t count, loff_t *off)
2411{
2412	int err;
2413	unsigned long num;
2414
2415	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2416		return -EACCES;
2417	err = kstrtoul_from_user(buffer, count, 0, &num);
2418	if (err)
2419		return err;
2420	sg_allow_dio = num ? 1 : 0;
 
2421	return count;
2422}
2423
2424static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2425{
2426	return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2427}
2428
2429static ssize_t 
2430sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2431		     size_t count, loff_t *off)
2432{
2433	int err;
2434	unsigned long k = ULONG_MAX;
 
2435
2436	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2437		return -EACCES;
2438
2439	err = kstrtoul_from_user(buffer, count, 0, &k);
2440	if (err)
2441		return err;
 
2442	if (k <= 1048576) {	/* limit "big buff" to 1 MB */
2443		sg_big_buff = k;
2444		return count;
2445	}
2446	return -ERANGE;
2447}
2448
2449static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2450{
2451	seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2452		   sg_version_date);
2453	return 0;
2454}
2455
 
 
 
 
 
2456static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2457{
2458	seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
 
2459	return 0;
2460}
2461
 
 
 
 
 
2462struct sg_proc_deviter {
2463	loff_t	index;
2464	size_t	max;
2465};
2466
2467static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2468{
2469	struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2470
2471	s->private = it;
2472	if (! it)
2473		return NULL;
2474
2475	it->index = *pos;
2476	it->max = sg_last_dev();
2477	if (it->index >= it->max)
2478		return NULL;
2479	return it;
2480}
2481
2482static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2483{
2484	struct sg_proc_deviter * it = s->private;
2485
2486	*pos = ++it->index;
2487	return (it->index < it->max) ? it : NULL;
2488}
2489
2490static void dev_seq_stop(struct seq_file *s, void *v)
2491{
2492	kfree(s->private);
2493}
2494
 
 
 
 
 
2495static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2496{
2497	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2498	Sg_device *sdp;
2499	struct scsi_device *scsidp;
2500	unsigned long iflags;
2501
2502	read_lock_irqsave(&sg_index_lock, iflags);
2503	sdp = it ? sg_lookup_dev(it->index) : NULL;
2504	if ((NULL == sdp) || (NULL == sdp->device) ||
2505	    (atomic_read(&sdp->detaching)))
2506		seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2507	else {
2508		scsidp = sdp->device;
2509		seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2510			      scsidp->host->host_no, scsidp->channel,
2511			      scsidp->id, scsidp->lun, (int) scsidp->type,
2512			      1,
2513			      (int) scsidp->queue_depth,
2514			      (int) atomic_read(&scsidp->device_busy),
2515			      (int) scsi_device_online(scsidp));
2516	}
 
2517	read_unlock_irqrestore(&sg_index_lock, iflags);
2518	return 0;
2519}
2520
 
 
 
 
 
2521static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2522{
2523	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2524	Sg_device *sdp;
2525	struct scsi_device *scsidp;
2526	unsigned long iflags;
2527
2528	read_lock_irqsave(&sg_index_lock, iflags);
2529	sdp = it ? sg_lookup_dev(it->index) : NULL;
2530	scsidp = sdp ? sdp->device : NULL;
2531	if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2532		seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2533			   scsidp->vendor, scsidp->model, scsidp->rev);
2534	else
2535		seq_puts(s, "<no active device>\n");
2536	read_unlock_irqrestore(&sg_index_lock, iflags);
2537	return 0;
2538}
2539
2540/* must be called while holding sg_index_lock */
2541static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2542{
2543	int k, new_interface, blen, usg;
2544	Sg_request *srp;
2545	Sg_fd *fp;
2546	const sg_io_hdr_t *hp;
2547	const char * cp;
2548	unsigned int ms;
2549
2550	k = 0;
2551	list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2552		k++;
2553		read_lock(&fp->rq_list_lock); /* irqs already disabled */
2554		seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2555			   "(res)sgat=%d low_dma=%d\n", k,
2556			   jiffies_to_msecs(fp->timeout),
2557			   fp->reserve.bufflen,
2558			   (int) fp->reserve.k_use_sg,
2559			   (int) sdp->device->host->unchecked_isa_dma);
2560		seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2561			   (int) fp->cmd_q, (int) fp->force_packid,
2562			   (int) fp->keep_orphan);
2563		list_for_each_entry(srp, &fp->rq_list, entry) {
 
 
2564			hp = &srp->header;
2565			new_interface = (hp->interface_id == '\0') ? 0 : 1;
2566			if (srp->res_used) {
2567				if (new_interface &&
2568				    (SG_FLAG_MMAP_IO & hp->flags))
2569					cp = "     mmap>> ";
2570				else
2571					cp = "     rb>> ";
2572			} else {
2573				if (SG_INFO_DIRECT_IO_MASK & hp->info)
2574					cp = "     dio>> ";
2575				else
2576					cp = "     ";
2577			}
2578			seq_puts(s, cp);
2579			blen = srp->data.bufflen;
2580			usg = srp->data.k_use_sg;
2581			seq_puts(s, srp->done ?
2582				 ((1 == srp->done) ?  "rcv:" : "fin:")
2583				  : "act:");
2584			seq_printf(s, " id=%d blen=%d",
2585				   srp->header.pack_id, blen);
2586			if (srp->done)
2587				seq_printf(s, " dur=%d", hp->duration);
2588			else {
2589				ms = jiffies_to_msecs(jiffies);
2590				seq_printf(s, " t_o/elap=%d/%d",
2591					(new_interface ? hp->timeout :
2592						  jiffies_to_msecs(fp->timeout)),
2593					(ms > hp->duration ? ms - hp->duration : 0));
2594			}
2595			seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2596				   (int) srp->data.cmd_opcode);
2597		}
2598		if (list_empty(&fp->rq_list))
2599			seq_puts(s, "     No requests active\n");
2600		read_unlock(&fp->rq_list_lock);
2601	}
2602}
2603
 
 
 
 
 
2604static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2605{
2606	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2607	Sg_device *sdp;
2608	unsigned long iflags;
2609
2610	if (it && (0 == it->index))
2611		seq_printf(s, "max_active_device=%d  def_reserved_size=%d\n",
2612			   (int)it->max, sg_big_buff);
 
 
2613
2614	read_lock_irqsave(&sg_index_lock, iflags);
2615	sdp = it ? sg_lookup_dev(it->index) : NULL;
2616	if (NULL == sdp)
2617		goto skip;
2618	read_lock(&sdp->sfd_lock);
2619	if (!list_empty(&sdp->sfds)) {
2620		seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2621		if (atomic_read(&sdp->detaching))
2622			seq_puts(s, "detaching pending close ");
2623		else if (sdp->device) {
2624			struct scsi_device *scsidp = sdp->device;
2625
2626			seq_printf(s, "%d:%d:%d:%llu   em=%d",
2627				   scsidp->host->host_no,
2628				   scsidp->channel, scsidp->id,
2629				   scsidp->lun,
2630				   scsidp->host->hostt->emulated);
2631		}
2632		seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2633			   sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2634		sg_proc_debug_helper(s, sdp);
2635	}
2636	read_unlock(&sdp->sfd_lock);
2637skip:
2638	read_unlock_irqrestore(&sg_index_lock, iflags);
2639	return 0;
2640}
2641
2642#endif				/* CONFIG_SCSI_PROC_FS */
2643
2644module_init(init_sg);
2645module_exit(exit_sg);