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
7 * Original driver (sg.c):
8 * Copyright (C) 1992 Lawrence Foard
9 * Version 2 and 3 extensions to driver:
10 * Copyright (C) 1998 - 2014 Douglas Gilbert
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
19 static int sg_version_num = 30536; /* 2 digits for each component */
20 #define SG_VERSION_STR "3.5.36"
23 * D. P. Gilbert (dgilbert@interlog.com), notes:
24 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
25 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
26 * (otherwise the macros compile to empty statements).
29 #include <linux/module.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/string.h>
36 #include <linux/errno.h>
37 #include <linux/mtio.h>
38 #include <linux/ioctl.h>
39 #include <linux/slab.h>
40 #include <linux/fcntl.h>
41 #include <linux/init.h>
42 #include <linux/poll.h>
43 #include <linux/moduleparam.h>
44 #include <linux/cdev.h>
45 #include <linux/idr.h>
46 #include <linux/seq_file.h>
47 #include <linux/blkdev.h>
48 #include <linux/delay.h>
49 #include <linux/blktrace_api.h>
50 #include <linux/mutex.h>
51 #include <linux/atomic.h>
52 #include <linux/ratelimit.h>
53 #include <linux/uio.h>
56 #include <scsi/scsi_dbg.h>
57 #include <scsi/scsi_host.h>
58 #include <scsi/scsi_driver.h>
59 #include <scsi/scsi_ioctl.h>
62 #include "scsi_logging.h"
64 #ifdef CONFIG_SCSI_PROC_FS
65 #include <linux/proc_fs.h>
66 static char *sg_version_date = "20140603";
68 static int sg_proc_init(void);
69 static void sg_proc_cleanup(void);
72 #define SG_ALLOW_DIO_DEF 0
74 #define SG_MAX_DEVS 32768
76 /* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
78 * than 16 bytes are "variable length" whose length is a multiple of 4
80 #define SG_MAX_CDB_SIZE 252
82 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
84 int sg_big_buff = SG_DEF_RESERVED_SIZE;
85 /* N.B. This variable is readable and writeable via
86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
87 of this size (or less if there is not enough memory) will be reserved
88 for use by this file descriptor. [Deprecated usage: this variable is also
89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
90 the kernel (i.e. it is not a module).] */
91 static int def_reserved_size = -1; /* picks up init parameter */
92 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
94 static int scatter_elem_sz = SG_SCATTER_SZ;
95 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
97 #define SG_SECTOR_SZ 512
99 static int sg_add_device(struct device *, struct class_interface *);
100 static void sg_remove_device(struct device *, struct class_interface *);
102 static DEFINE_IDR(sg_index_idr);
103 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
106 static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
111 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
114 unsigned bufflen; /* Size of (aggregate) data buffer */
117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
118 unsigned char cmd_opcode; /* first byte of command */
121 struct sg_device; /* forward declarations */
124 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
125 struct list_head entry; /* list entry */
126 struct sg_fd *parentfp; /* NULL -> not in use */
127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
131 char orphan; /* 1 -> drop on sight, 0 -> normal */
132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
133 /* done protected by rq_list_lock */
134 char done; /* 0->before bh, 1->before read, 2->read */
137 struct execute_work ew;
140 typedef struct sg_fd { /* holds the state of a file descriptor */
141 struct list_head sfd_siblings; /* protected by device's sfd_lock */
142 struct sg_device *parentdp; /* owning device */
143 wait_queue_head_t read_wait; /* queue read until command done */
144 rwlock_t rq_list_lock; /* protect access to list in req_arr */
145 struct mutex f_mutex; /* protect against changes in this fd */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 struct list_head rq_list; /* head of request list */
150 struct fasync_struct *async_qp; /* used by asynchronous notification */
151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
152 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
156 char mmap_called; /* 0 -> mmap() never called on this fd */
157 char res_in_use; /* 1 -> 'reserve' array in use */
159 struct execute_work ew;
162 typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
165 struct mutex open_rel_lock; /* held when in open() or release() */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 struct list_head sfds;
169 rwlock_t sfd_lock; /* protect access to sfd list */
170 atomic_t detaching; /* 0->device usable, 1->device detaching */
171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174 struct gendisk *disk;
175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
179 /* tasklet or soft irq callback */
180 static void sg_rq_end_io(struct request *rq, blk_status_t status);
181 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182 static int sg_finish_rem_req(Sg_request * srp);
183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, int sg_io_owned, Sg_request **o_srp);
189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196 static Sg_fd *sg_add_sfp(Sg_device * sdp);
197 static void sg_remove_sfp(struct kref *);
198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
199 static Sg_request *sg_add_request(Sg_fd * sfp);
200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201 static Sg_device *sg_get_dev(int dev);
202 static void sg_device_destroy(struct kref *kref);
204 #define SZ_SG_HEADER sizeof(struct sg_header)
205 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
206 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
207 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
209 #define sg_printk(prefix, sdp, fmt, a...) \
210 sdev_prefix_printk(prefix, (sdp)->device, \
211 (sdp)->disk->disk_name, fmt, ##a)
213 static int sg_allow_access(struct file *filp, unsigned char *cmd)
215 struct sg_fd *sfp = filp->private_data;
217 if (sfp->parentdp->device->type == TYPE_SCANNER)
220 return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
224 open_wait(Sg_device *sdp, int flags)
228 if (flags & O_EXCL) {
229 while (sdp->open_cnt > 0) {
230 mutex_unlock(&sdp->open_rel_lock);
231 retval = wait_event_interruptible(sdp->open_wait,
232 (atomic_read(&sdp->detaching) ||
234 mutex_lock(&sdp->open_rel_lock);
236 if (retval) /* -ERESTARTSYS */
238 if (atomic_read(&sdp->detaching))
242 while (sdp->exclude) {
243 mutex_unlock(&sdp->open_rel_lock);
244 retval = wait_event_interruptible(sdp->open_wait,
245 (atomic_read(&sdp->detaching) ||
247 mutex_lock(&sdp->open_rel_lock);
249 if (retval) /* -ERESTARTSYS */
251 if (atomic_read(&sdp->detaching))
259 /* Returns 0 on success, else a negated errno value */
261 sg_open(struct inode *inode, struct file *filp)
263 int dev = iminor(inode);
264 int flags = filp->f_flags;
265 struct request_queue *q;
270 nonseekable_open(inode, filp);
271 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
272 return -EPERM; /* Can't lock it with read only access */
273 sdp = sg_get_dev(dev);
277 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
278 "sg_open: flags=0x%x\n", flags));
280 /* This driver's module count bumped by fops_get in <linux/fs.h> */
281 /* Prevent the device driver from vanishing while we sleep */
282 retval = scsi_device_get(sdp->device);
286 retval = scsi_autopm_get_device(sdp->device);
290 /* scsi_block_when_processing_errors() may block so bypass
291 * check if O_NONBLOCK. Permits SCSI commands to be issued
292 * during error recovery. Tread carefully. */
293 if (!((flags & O_NONBLOCK) ||
294 scsi_block_when_processing_errors(sdp->device))) {
296 /* we are in error recovery for this device */
300 mutex_lock(&sdp->open_rel_lock);
301 if (flags & O_NONBLOCK) {
302 if (flags & O_EXCL) {
303 if (sdp->open_cnt > 0) {
305 goto error_mutex_locked;
310 goto error_mutex_locked;
314 retval = open_wait(sdp, flags);
315 if (retval) /* -ERESTARTSYS or -ENODEV */
316 goto error_mutex_locked;
319 /* N.B. at this point we are holding the open_rel_lock */
323 if (sdp->open_cnt < 1) { /* no existing opens */
325 q = sdp->device->request_queue;
326 sdp->sg_tablesize = queue_max_segments(q);
328 sfp = sg_add_sfp(sdp);
330 retval = PTR_ERR(sfp);
334 filp->private_data = sfp;
336 mutex_unlock(&sdp->open_rel_lock);
340 kref_put(&sdp->d_ref, sg_device_destroy);
344 if (flags & O_EXCL) {
345 sdp->exclude = false; /* undo if error */
346 wake_up_interruptible(&sdp->open_wait);
349 mutex_unlock(&sdp->open_rel_lock);
351 scsi_autopm_put_device(sdp->device);
353 scsi_device_put(sdp->device);
357 /* Release resources associated with a successful sg_open()
358 * Returns 0 on success, else a negated errno value */
360 sg_release(struct inode *inode, struct file *filp)
365 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
367 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
369 mutex_lock(&sdp->open_rel_lock);
370 scsi_autopm_put_device(sdp->device);
371 kref_put(&sfp->f_ref, sg_remove_sfp);
374 /* possibly many open()s waiting on exlude clearing, start many;
375 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
377 sdp->exclude = false;
378 wake_up_interruptible_all(&sdp->open_wait);
379 } else if (0 == sdp->open_cnt) {
380 wake_up_interruptible(&sdp->open_wait);
382 mutex_unlock(&sdp->open_rel_lock);
387 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
392 int req_pack_id = -1;
394 struct sg_header *old_hdr = NULL;
397 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
399 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
400 "sg_read: count=%d\n", (int) count));
402 if (!access_ok(VERIFY_WRITE, buf, count))
404 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
405 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
408 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
412 if (old_hdr->reply_len < 0) {
413 if (count >= SZ_SG_IO_HDR) {
414 sg_io_hdr_t *new_hdr;
415 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
420 retval =__copy_from_user
421 (new_hdr, buf, SZ_SG_IO_HDR);
422 req_pack_id = new_hdr->pack_id;
430 req_pack_id = old_hdr->pack_id;
432 srp = sg_get_rq_mark(sfp, req_pack_id);
433 if (!srp) { /* now wait on packet to arrive */
434 if (atomic_read(&sdp->detaching)) {
438 if (filp->f_flags & O_NONBLOCK) {
442 retval = wait_event_interruptible(sfp->read_wait,
443 (atomic_read(&sdp->detaching) ||
444 (srp = sg_get_rq_mark(sfp, req_pack_id))));
445 if (atomic_read(&sdp->detaching)) {
450 /* -ERESTARTSYS as signal hit process */
454 if (srp->header.interface_id != '\0') {
455 retval = sg_new_read(sfp, buf, count, srp);
460 if (old_hdr == NULL) {
461 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
467 memset(old_hdr, 0, SZ_SG_HEADER);
468 old_hdr->reply_len = (int) hp->timeout;
469 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
470 old_hdr->pack_id = hp->pack_id;
471 old_hdr->twelve_byte =
472 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
473 old_hdr->target_status = hp->masked_status;
474 old_hdr->host_status = hp->host_status;
475 old_hdr->driver_status = hp->driver_status;
476 if ((CHECK_CONDITION & hp->masked_status) ||
477 (DRIVER_SENSE & hp->driver_status))
478 memcpy(old_hdr->sense_buffer, srp->sense_b,
479 sizeof (old_hdr->sense_buffer));
480 switch (hp->host_status) {
481 /* This setup of 'result' is for backward compatibility and is best
482 ignored by the user who should use target, host + driver status */
484 case DID_PASSTHROUGH:
491 old_hdr->result = EBUSY;
498 old_hdr->result = EIO;
501 old_hdr->result = (srp->sense_b[0] == 0 &&
502 hp->masked_status == GOOD) ? 0 : EIO;
505 old_hdr->result = EIO;
509 /* Now copy the result back to the user buffer. */
510 if (count >= SZ_SG_HEADER) {
511 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
516 if (count > old_hdr->reply_len)
517 count = old_hdr->reply_len;
518 if (count > SZ_SG_HEADER) {
519 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
525 count = (old_hdr->result == 0) ? 0 : -EIO;
526 sg_finish_rem_req(srp);
527 sg_remove_request(sfp, srp);
535 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
537 sg_io_hdr_t *hp = &srp->header;
541 if (count < SZ_SG_IO_HDR) {
546 if ((hp->mx_sb_len > 0) && hp->sbp) {
547 if ((CHECK_CONDITION & hp->masked_status) ||
548 (DRIVER_SENSE & hp->driver_status)) {
549 int sb_len = SCSI_SENSE_BUFFERSIZE;
550 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
551 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
552 len = (len > sb_len) ? sb_len : len;
553 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
560 if (hp->masked_status || hp->host_status || hp->driver_status)
561 hp->info |= SG_INFO_CHECK;
562 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
567 err2 = sg_finish_rem_req(srp);
568 sg_remove_request(sfp, srp);
569 return err ? : err2 ? : count;
573 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
575 int mxsize, cmd_size, k;
576 int input_size, blocking;
577 unsigned char opcode;
581 struct sg_header old_hdr;
583 unsigned char cmnd[SG_MAX_CDB_SIZE];
585 if (unlikely(uaccess_kernel()))
588 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
590 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
591 "sg_write: count=%d\n", (int) count));
592 if (atomic_read(&sdp->detaching))
594 if (!((filp->f_flags & O_NONBLOCK) ||
595 scsi_block_when_processing_errors(sdp->device)))
598 if (!access_ok(VERIFY_READ, buf, count))
599 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
600 if (count < SZ_SG_HEADER)
602 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
604 blocking = !(filp->f_flags & O_NONBLOCK);
605 if (old_hdr.reply_len < 0)
606 return sg_new_write(sfp, filp, buf, count,
607 blocking, 0, 0, NULL);
608 if (count < (SZ_SG_HEADER + 6))
609 return -EIO; /* The minimum scsi command length is 6 bytes. */
611 if (!(srp = sg_add_request(sfp))) {
612 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
613 "sg_write: queue full\n"));
617 __get_user(opcode, buf);
618 mutex_lock(&sfp->f_mutex);
619 if (sfp->next_cmd_len > 0) {
620 cmd_size = sfp->next_cmd_len;
621 sfp->next_cmd_len = 0; /* reset so only this write() effected */
623 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
624 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
627 mutex_unlock(&sfp->f_mutex);
628 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
629 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
630 /* Determine buffer size. */
631 input_size = count - cmd_size;
632 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
633 mxsize -= SZ_SG_HEADER;
634 input_size -= SZ_SG_HEADER;
635 if (input_size < 0) {
636 sg_remove_request(sfp, srp);
637 return -EIO; /* User did not pass enough bytes for this command. */
640 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
641 hp->cmd_len = (unsigned char) cmd_size;
645 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
646 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
648 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
649 hp->dxfer_len = mxsize;
650 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
651 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
652 hp->dxferp = (char __user *)buf + cmd_size;
656 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
657 hp->flags = input_size; /* structure abuse ... */
658 hp->pack_id = old_hdr.pack_id;
660 if (__copy_from_user(cmnd, buf, cmd_size))
663 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
664 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
665 * is a non-zero input_size, so emit a warning.
667 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
668 printk_ratelimited(KERN_WARNING
669 "sg_write: data in/out %d/%d bytes "
670 "for SCSI command 0x%x-- guessing "
671 "data in;\n program %s not setting "
672 "count and/or reply_len properly\n",
673 old_hdr.reply_len - (int)SZ_SG_HEADER,
674 input_size, (unsigned int) cmnd[0],
677 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
678 return (k < 0) ? k : count;
682 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
683 size_t count, int blocking, int read_only, int sg_io_owned,
689 unsigned char cmnd[SG_MAX_CDB_SIZE];
691 unsigned long ul_timeout;
693 if (count < SZ_SG_IO_HDR)
695 if (!access_ok(VERIFY_READ, buf, count))
696 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
698 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
699 if (!(srp = sg_add_request(sfp))) {
700 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
701 "sg_new_write: queue full\n"));
704 srp->sg_io_owned = sg_io_owned;
706 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
707 sg_remove_request(sfp, srp);
710 if (hp->interface_id != 'S') {
711 sg_remove_request(sfp, srp);
714 if (hp->flags & SG_FLAG_MMAP_IO) {
715 if (hp->dxfer_len > sfp->reserve.bufflen) {
716 sg_remove_request(sfp, srp);
717 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
719 if (hp->flags & SG_FLAG_DIRECT_IO) {
720 sg_remove_request(sfp, srp);
721 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
723 if (sfp->res_in_use) {
724 sg_remove_request(sfp, srp);
725 return -EBUSY; /* reserve buffer already being used */
728 ul_timeout = msecs_to_jiffies(srp->header.timeout);
729 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
730 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
731 sg_remove_request(sfp, srp);
734 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
735 sg_remove_request(sfp, srp);
736 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
738 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
739 sg_remove_request(sfp, srp);
742 if (read_only && sg_allow_access(file, cmnd)) {
743 sg_remove_request(sfp, srp);
746 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
754 static bool sg_is_valid_dxfer(sg_io_hdr_t *hp)
756 switch (hp->dxfer_direction) {
758 if (hp->dxferp || hp->dxfer_len > 0)
761 case SG_DXFER_FROM_DEV:
763 * for SG_DXFER_FROM_DEV we always set dxfer_len to > 0. dxferp
764 * can either be NULL or != NULL so there's no point in checking
765 * it either. So just return true.
768 case SG_DXFER_TO_DEV:
769 case SG_DXFER_TO_FROM_DEV:
770 if (!hp->dxferp || hp->dxfer_len == 0)
773 case SG_DXFER_UNKNOWN:
774 if ((!hp->dxferp && hp->dxfer_len) ||
775 (hp->dxferp && hp->dxfer_len == 0))
784 sg_common_write(Sg_fd * sfp, Sg_request * srp,
785 unsigned char *cmnd, int timeout, int blocking)
788 Sg_device *sdp = sfp->parentdp;
789 sg_io_hdr_t *hp = &srp->header;
791 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
793 hp->masked_status = 0;
797 hp->driver_status = 0;
799 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
800 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
801 (int) cmnd[0], (int) hp->cmd_len));
803 if (!sg_is_valid_dxfer(hp))
806 k = sg_start_req(srp, cmnd);
808 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
809 "sg_common_write: start_req err=%d\n", k));
810 sg_finish_rem_req(srp);
811 sg_remove_request(sfp, srp);
812 return k; /* probably out of space --> ENOMEM */
814 if (atomic_read(&sdp->detaching)) {
816 scsi_req_free_cmd(scsi_req(srp->rq));
817 blk_end_request_all(srp->rq, BLK_STS_IOERR);
821 sg_finish_rem_req(srp);
822 sg_remove_request(sfp, srp);
826 hp->duration = jiffies_to_msecs(jiffies);
827 if (hp->interface_id != '\0' && /* v3 (or later) interface */
828 (SG_FLAG_Q_AT_TAIL & hp->flags))
833 srp->rq->timeout = timeout;
834 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
835 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
836 srp->rq, at_head, sg_rq_end_io);
840 static int srp_done(Sg_fd *sfp, Sg_request *srp)
845 read_lock_irqsave(&sfp->rq_list_lock, flags);
847 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
851 static int max_sectors_bytes(struct request_queue *q)
853 unsigned int max_sectors = queue_max_sectors(q);
855 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
857 return max_sectors << 9;
861 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
863 void __user *p = (void __user *)arg;
865 int result, val, read_only;
869 unsigned long iflags;
871 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
874 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
875 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
876 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
880 if (atomic_read(&sdp->detaching))
882 if (!scsi_block_when_processing_errors(sdp->device))
884 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
886 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
887 1, read_only, 1, &srp);
890 result = wait_event_interruptible(sfp->read_wait,
891 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
892 if (atomic_read(&sdp->detaching))
894 write_lock_irq(&sfp->rq_list_lock);
897 write_unlock_irq(&sfp->rq_list_lock);
898 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
899 return (result < 0) ? result : 0;
902 write_unlock_irq(&sfp->rq_list_lock);
903 return result; /* -ERESTARTSYS because signal hit process */
905 result = get_user(val, ip);
910 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
911 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
913 sfp->timeout_user = val;
914 sfp->timeout = mult_frac(val, HZ, USER_HZ);
917 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
918 /* strange ..., for backward compatibility */
919 return sfp->timeout_user;
920 case SG_SET_FORCE_LOW_DMA:
922 * N.B. This ioctl never worked properly, but failed to
923 * return an error value. So returning '0' to keep compability
924 * with legacy applications.
928 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
930 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
933 sg_scsi_id_t __user *sg_idp = p;
935 if (atomic_read(&sdp->detaching))
937 __put_user((int) sdp->device->host->host_no,
939 __put_user((int) sdp->device->channel,
941 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
942 __put_user((int) sdp->device->lun, &sg_idp->lun);
943 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
944 __put_user((short) sdp->device->host->cmd_per_lun,
945 &sg_idp->h_cmd_per_lun);
946 __put_user((short) sdp->device->queue_depth,
947 &sg_idp->d_queue_depth);
948 __put_user(0, &sg_idp->unused[0]);
949 __put_user(0, &sg_idp->unused[1]);
952 case SG_SET_FORCE_PACK_ID:
953 result = get_user(val, ip);
956 sfp->force_packid = val ? 1 : 0;
959 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
961 read_lock_irqsave(&sfp->rq_list_lock, iflags);
962 list_for_each_entry(srp, &sfp->rq_list, entry) {
963 if ((1 == srp->done) && (!srp->sg_io_owned)) {
964 read_unlock_irqrestore(&sfp->rq_list_lock,
966 __put_user(srp->header.pack_id, ip);
970 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
973 case SG_GET_NUM_WAITING:
974 read_lock_irqsave(&sfp->rq_list_lock, iflags);
976 list_for_each_entry(srp, &sfp->rq_list, entry) {
977 if ((1 == srp->done) && (!srp->sg_io_owned))
980 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
981 return put_user(val, ip);
982 case SG_GET_SG_TABLESIZE:
983 return put_user(sdp->sg_tablesize, ip);
984 case SG_SET_RESERVED_SIZE:
985 result = get_user(val, ip);
990 val = min_t(int, val,
991 max_sectors_bytes(sdp->device->request_queue));
992 mutex_lock(&sfp->f_mutex);
993 if (val != sfp->reserve.bufflen) {
994 if (sfp->mmap_called ||
996 mutex_unlock(&sfp->f_mutex);
1000 sg_remove_scat(sfp, &sfp->reserve);
1001 sg_build_reserve(sfp, val);
1003 mutex_unlock(&sfp->f_mutex);
1005 case SG_GET_RESERVED_SIZE:
1006 val = min_t(int, sfp->reserve.bufflen,
1007 max_sectors_bytes(sdp->device->request_queue));
1008 return put_user(val, ip);
1009 case SG_SET_COMMAND_Q:
1010 result = get_user(val, ip);
1013 sfp->cmd_q = val ? 1 : 0;
1015 case SG_GET_COMMAND_Q:
1016 return put_user((int) sfp->cmd_q, ip);
1017 case SG_SET_KEEP_ORPHAN:
1018 result = get_user(val, ip);
1021 sfp->keep_orphan = val;
1023 case SG_GET_KEEP_ORPHAN:
1024 return put_user((int) sfp->keep_orphan, ip);
1025 case SG_NEXT_CMD_LEN:
1026 result = get_user(val, ip);
1029 if (val > SG_MAX_CDB_SIZE)
1031 sfp->next_cmd_len = (val > 0) ? val : 0;
1033 case SG_GET_VERSION_NUM:
1034 return put_user(sg_version_num, ip);
1035 case SG_GET_ACCESS_COUNT:
1036 /* faked - we don't have a real access count anymore */
1037 val = (sdp->device ? 1 : 0);
1038 return put_user(val, ip);
1039 case SG_GET_REQUEST_TABLE:
1040 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1043 sg_req_info_t *rinfo;
1046 rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1050 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1052 list_for_each_entry(srp, &sfp->rq_list, entry) {
1053 if (val > SG_MAX_QUEUE)
1055 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
1056 rinfo[val].req_state = srp->done + 1;
1057 rinfo[val].problem =
1058 srp->header.masked_status &
1059 srp->header.host_status &
1060 srp->header.driver_status;
1062 rinfo[val].duration =
1063 srp->header.duration;
1065 ms = jiffies_to_msecs(jiffies);
1066 rinfo[val].duration =
1067 (ms > srp->header.duration) ?
1068 (ms - srp->header.duration) : 0;
1070 rinfo[val].orphan = srp->orphan;
1071 rinfo[val].sg_io_owned = srp->sg_io_owned;
1072 rinfo[val].pack_id = srp->header.pack_id;
1073 rinfo[val].usr_ptr = srp->header.usr_ptr;
1076 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1077 result = __copy_to_user(p, rinfo,
1078 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1079 result = result ? -EFAULT : 0;
1083 case SG_EMULATED_HOST:
1084 if (atomic_read(&sdp->detaching))
1086 return put_user(sdp->device->host->hostt->emulated, ip);
1087 case SCSI_IOCTL_SEND_COMMAND:
1088 if (atomic_read(&sdp->detaching))
1091 unsigned char opcode = WRITE_6;
1092 Scsi_Ioctl_Command __user *siocp = p;
1094 if (copy_from_user(&opcode, siocp->data, 1))
1096 if (sg_allow_access(filp, &opcode))
1099 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1101 result = get_user(val, ip);
1104 sdp->sgdebug = (char) val;
1107 return put_user(max_sectors_bytes(sdp->device->request_queue),
1110 return blk_trace_setup(sdp->device->request_queue,
1111 sdp->disk->disk_name,
1112 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1116 return blk_trace_startstop(sdp->device->request_queue, 1);
1118 return blk_trace_startstop(sdp->device->request_queue, 0);
1119 case BLKTRACETEARDOWN:
1120 return blk_trace_remove(sdp->device->request_queue);
1121 case SCSI_IOCTL_GET_IDLUN:
1122 case SCSI_IOCTL_GET_BUS_NUMBER:
1123 case SCSI_IOCTL_PROBE_HOST:
1124 case SG_GET_TRANSFORM:
1126 if (atomic_read(&sdp->detaching))
1131 return -EPERM; /* don't know so take safe approach */
1135 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1136 cmd_in, filp->f_flags & O_NDELAY);
1139 return scsi_ioctl(sdp->device, cmd_in, p);
1142 #ifdef CONFIG_COMPAT
1143 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1147 struct scsi_device *sdev;
1149 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1153 if (sdev->host->hostt->compat_ioctl) {
1156 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1161 return -ENOIOCTLCMD;
1166 sg_poll(struct file *filp, poll_table * wait)
1168 unsigned int res = 0;
1173 unsigned long iflags;
1175 sfp = filp->private_data;
1178 sdp = sfp->parentdp;
1181 poll_wait(filp, &sfp->read_wait, wait);
1182 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1183 list_for_each_entry(srp, &sfp->rq_list, entry) {
1184 /* if any read waiting, flag it */
1185 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1186 res = POLLIN | POLLRDNORM;
1189 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1191 if (atomic_read(&sdp->detaching))
1193 else if (!sfp->cmd_q) {
1195 res |= POLLOUT | POLLWRNORM;
1196 } else if (count < SG_MAX_QUEUE)
1197 res |= POLLOUT | POLLWRNORM;
1198 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1199 "sg_poll: res=0x%x\n", (int) res));
1204 sg_fasync(int fd, struct file *filp, int mode)
1209 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1211 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1212 "sg_fasync: mode=%d\n", mode));
1214 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1218 sg_vma_fault(struct vm_fault *vmf)
1220 struct vm_area_struct *vma = vmf->vma;
1222 unsigned long offset, len, sa;
1223 Sg_scatter_hold *rsv_schp;
1226 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1227 return VM_FAULT_SIGBUS;
1228 rsv_schp = &sfp->reserve;
1229 offset = vmf->pgoff << PAGE_SHIFT;
1230 if (offset >= rsv_schp->bufflen)
1231 return VM_FAULT_SIGBUS;
1232 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1233 "sg_vma_fault: offset=%lu, scatg=%d\n",
1234 offset, rsv_schp->k_use_sg));
1236 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1237 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1238 len = vma->vm_end - sa;
1239 len = (len < length) ? len : length;
1241 struct page *page = nth_page(rsv_schp->pages[k],
1242 offset >> PAGE_SHIFT);
1243 get_page(page); /* increment page count */
1245 return 0; /* success */
1251 return VM_FAULT_SIGBUS;
1254 static const struct vm_operations_struct sg_mmap_vm_ops = {
1255 .fault = sg_vma_fault,
1259 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1262 unsigned long req_sz, len, sa;
1263 Sg_scatter_hold *rsv_schp;
1266 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1268 req_sz = vma->vm_end - vma->vm_start;
1269 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1270 "sg_mmap starting, vm_start=%p, len=%d\n",
1271 (void *) vma->vm_start, (int) req_sz));
1273 return -EINVAL; /* want no offset */
1274 rsv_schp = &sfp->reserve;
1275 if (req_sz > rsv_schp->bufflen)
1276 return -ENOMEM; /* cannot map more than reserved buffer */
1279 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1280 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1281 len = vma->vm_end - sa;
1282 len = (len < length) ? len : length;
1286 sfp->mmap_called = 1;
1287 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1288 vma->vm_private_data = sfp;
1289 vma->vm_ops = &sg_mmap_vm_ops;
1294 sg_rq_end_io_usercontext(struct work_struct *work)
1296 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1297 struct sg_fd *sfp = srp->parentfp;
1299 sg_finish_rem_req(srp);
1300 sg_remove_request(sfp, srp);
1301 kref_put(&sfp->f_ref, sg_remove_sfp);
1305 * This function is a "bottom half" handler that is called by the mid
1306 * level when a command is completed (or has failed).
1309 sg_rq_end_io(struct request *rq, blk_status_t status)
1311 struct sg_request *srp = rq->end_io_data;
1312 struct scsi_request *req = scsi_req(rq);
1315 unsigned long iflags;
1318 int result, resid, done = 1;
1320 if (WARN_ON(srp->done != 0))
1323 sfp = srp->parentfp;
1324 if (WARN_ON(sfp == NULL))
1327 sdp = sfp->parentdp;
1328 if (unlikely(atomic_read(&sdp->detaching)))
1329 pr_info("%s: device detaching\n", __func__);
1332 result = req->result;
1333 resid = req->resid_len;
1335 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1336 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1337 srp->header.pack_id, result));
1338 srp->header.resid = resid;
1339 ms = jiffies_to_msecs(jiffies);
1340 srp->header.duration = (ms > srp->header.duration) ?
1341 (ms - srp->header.duration) : 0;
1343 struct scsi_sense_hdr sshdr;
1345 srp->header.status = 0xff & result;
1346 srp->header.masked_status = status_byte(result);
1347 srp->header.msg_status = msg_byte(result);
1348 srp->header.host_status = host_byte(result);
1349 srp->header.driver_status = driver_byte(result);
1350 if ((sdp->sgdebug > 0) &&
1351 ((CHECK_CONDITION == srp->header.masked_status) ||
1352 (COMMAND_TERMINATED == srp->header.masked_status)))
1353 __scsi_print_sense(sdp->device, __func__, sense,
1354 SCSI_SENSE_BUFFERSIZE);
1356 /* Following if statement is a patch supplied by Eric Youngdale */
1357 if (driver_byte(result) != 0
1358 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1359 && !scsi_sense_is_deferred(&sshdr)
1360 && sshdr.sense_key == UNIT_ATTENTION
1361 && sdp->device->removable) {
1362 /* Detected possible disc change. Set the bit - this */
1363 /* may be used if there are filesystems using this device */
1364 sdp->device->changed = 1;
1369 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1371 /* Rely on write phase to clean out srp status values, so no "else" */
1374 * Free the request as soon as it is complete so that its resources
1375 * can be reused without waiting for userspace to read() the
1376 * result. But keep the associated bio (if any) around until
1377 * blk_rq_unmap_user() can be called from user context.
1380 scsi_req_free_cmd(scsi_req(rq));
1381 __blk_put_request(rq->q, rq);
1383 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1384 if (unlikely(srp->orphan)) {
1385 if (sfp->keep_orphan)
1386 srp->sg_io_owned = 0;
1391 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1394 /* Now wake up any sg_read() that is waiting for this
1397 wake_up_interruptible(&sfp->read_wait);
1398 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1399 kref_put(&sfp->f_ref, sg_remove_sfp);
1401 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1402 schedule_work(&srp->ew.work);
1406 static const struct file_operations sg_fops = {
1407 .owner = THIS_MODULE,
1411 .unlocked_ioctl = sg_ioctl,
1412 #ifdef CONFIG_COMPAT
1413 .compat_ioctl = sg_compat_ioctl,
1417 .release = sg_release,
1418 .fasync = sg_fasync,
1419 .llseek = no_llseek,
1422 static struct class *sg_sysfs_class;
1424 static int sg_sysfs_valid = 0;
1427 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1429 struct request_queue *q = scsidp->request_queue;
1431 unsigned long iflags;
1435 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1437 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1438 "failure\n", __func__);
1439 return ERR_PTR(-ENOMEM);
1442 idr_preload(GFP_KERNEL);
1443 write_lock_irqsave(&sg_index_lock, iflags);
1445 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1447 if (error == -ENOSPC) {
1448 sdev_printk(KERN_WARNING, scsidp,
1449 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1450 scsidp->type, SG_MAX_DEVS - 1);
1453 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1454 "allocation Sg_device failure: %d\n",
1461 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1462 "sg_alloc: dev=%d \n", k));
1463 sprintf(disk->disk_name, "sg%d", k);
1464 disk->first_minor = k;
1466 sdp->device = scsidp;
1467 mutex_init(&sdp->open_rel_lock);
1468 INIT_LIST_HEAD(&sdp->sfds);
1469 init_waitqueue_head(&sdp->open_wait);
1470 atomic_set(&sdp->detaching, 0);
1471 rwlock_init(&sdp->sfd_lock);
1472 sdp->sg_tablesize = queue_max_segments(q);
1474 kref_init(&sdp->d_ref);
1478 write_unlock_irqrestore(&sg_index_lock, iflags);
1483 return ERR_PTR(error);
1489 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1491 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1492 struct gendisk *disk;
1493 Sg_device *sdp = NULL;
1494 struct cdev * cdev = NULL;
1496 unsigned long iflags;
1498 disk = alloc_disk(1);
1500 pr_warn("%s: alloc_disk failed\n", __func__);
1503 disk->major = SCSI_GENERIC_MAJOR;
1506 cdev = cdev_alloc();
1508 pr_warn("%s: cdev_alloc failed\n", __func__);
1511 cdev->owner = THIS_MODULE;
1512 cdev->ops = &sg_fops;
1514 sdp = sg_alloc(disk, scsidp);
1516 pr_warn("%s: sg_alloc failed\n", __func__);
1517 error = PTR_ERR(sdp);
1521 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1526 if (sg_sysfs_valid) {
1527 struct device *sg_class_member;
1529 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1530 MKDEV(SCSI_GENERIC_MAJOR,
1532 sdp, "%s", disk->disk_name);
1533 if (IS_ERR(sg_class_member)) {
1534 pr_err("%s: device_create failed\n", __func__);
1535 error = PTR_ERR(sg_class_member);
1538 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1539 &sg_class_member->kobj, "generic");
1541 pr_err("%s: unable to make symlink 'generic' back "
1542 "to sg%d\n", __func__, sdp->index);
1544 pr_warn("%s: sg_sys Invalid\n", __func__);
1546 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1547 "type %d\n", sdp->index, scsidp->type);
1549 dev_set_drvdata(cl_dev, sdp);
1554 write_lock_irqsave(&sg_index_lock, iflags);
1555 idr_remove(&sg_index_idr, sdp->index);
1556 write_unlock_irqrestore(&sg_index_lock, iflags);
1567 sg_device_destroy(struct kref *kref)
1569 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1570 unsigned long flags;
1572 /* CAUTION! Note that the device can still be found via idr_find()
1573 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1574 * any other cleanup.
1577 write_lock_irqsave(&sg_index_lock, flags);
1578 idr_remove(&sg_index_idr, sdp->index);
1579 write_unlock_irqrestore(&sg_index_lock, flags);
1582 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1584 put_disk(sdp->disk);
1589 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1591 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1592 Sg_device *sdp = dev_get_drvdata(cl_dev);
1593 unsigned long iflags;
1599 /* want sdp->detaching non-zero as soon as possible */
1600 val = atomic_inc_return(&sdp->detaching);
1602 return; /* only want to do following once per device */
1604 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1607 read_lock_irqsave(&sdp->sfd_lock, iflags);
1608 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1609 wake_up_interruptible_all(&sfp->read_wait);
1610 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1612 wake_up_interruptible_all(&sdp->open_wait);
1613 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1615 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1616 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1617 cdev_del(sdp->cdev);
1620 kref_put(&sdp->d_ref, sg_device_destroy);
1623 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1624 module_param_named(def_reserved_size, def_reserved_size, int,
1626 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1628 MODULE_AUTHOR("Douglas Gilbert");
1629 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1630 MODULE_LICENSE("GPL");
1631 MODULE_VERSION(SG_VERSION_STR);
1632 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1634 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1635 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1636 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1637 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1644 if (scatter_elem_sz < PAGE_SIZE) {
1645 scatter_elem_sz = PAGE_SIZE;
1646 scatter_elem_sz_prev = scatter_elem_sz;
1648 if (def_reserved_size >= 0)
1649 sg_big_buff = def_reserved_size;
1651 def_reserved_size = sg_big_buff;
1653 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1657 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1658 if ( IS_ERR(sg_sysfs_class) ) {
1659 rc = PTR_ERR(sg_sysfs_class);
1663 rc = scsi_register_interface(&sg_interface);
1665 #ifdef CONFIG_SCSI_PROC_FS
1667 #endif /* CONFIG_SCSI_PROC_FS */
1670 class_destroy(sg_sysfs_class);
1672 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1679 #ifdef CONFIG_SCSI_PROC_FS
1681 #endif /* CONFIG_SCSI_PROC_FS */
1682 scsi_unregister_interface(&sg_interface);
1683 class_destroy(sg_sysfs_class);
1685 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1687 idr_destroy(&sg_index_idr);
1691 sg_start_req(Sg_request *srp, unsigned char *cmd)
1695 struct scsi_request *req;
1696 Sg_fd *sfp = srp->parentfp;
1697 sg_io_hdr_t *hp = &srp->header;
1698 int dxfer_len = (int) hp->dxfer_len;
1699 int dxfer_dir = hp->dxfer_direction;
1700 unsigned int iov_count = hp->iovec_count;
1701 Sg_scatter_hold *req_schp = &srp->data;
1702 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1703 struct request_queue *q = sfp->parentdp->device->request_queue;
1704 struct rq_map_data *md, map_data;
1705 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1706 unsigned char *long_cmdp = NULL;
1708 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1709 "sg_start_req: dxfer_len=%d\n",
1712 if (hp->cmd_len > BLK_MAX_CDB) {
1713 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1721 * With scsi-mq enabled, there are a fixed number of preallocated
1722 * requests equal in number to shost->can_queue. If all of the
1723 * preallocated requests are already in use, then using GFP_ATOMIC with
1724 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1725 * will cause blk_get_request() to sleep until an active command
1726 * completes, freeing up a request. Neither option is ideal, but
1727 * GFP_KERNEL is the better choice to prevent userspace from getting an
1728 * unexpected EWOULDBLOCK.
1730 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1731 * does not sleep except under memory pressure.
1733 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1734 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, GFP_KERNEL);
1741 if (hp->cmd_len > BLK_MAX_CDB)
1742 req->cmd = long_cmdp;
1743 memcpy(req->cmd, cmd, hp->cmd_len);
1744 req->cmd_len = hp->cmd_len;
1747 rq->end_io_data = srp;
1748 req->retries = SG_DEFAULT_RETRIES;
1750 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1753 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1754 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1755 !sfp->parentdp->device->host->unchecked_isa_dma &&
1756 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1762 mutex_lock(&sfp->f_mutex);
1763 if (dxfer_len <= rsv_schp->bufflen &&
1765 sfp->res_in_use = 1;
1766 sg_link_reserve(sfp, srp, dxfer_len);
1767 } else if ((hp->flags & SG_FLAG_MMAP_IO) && sfp->res_in_use) {
1768 mutex_unlock(&sfp->f_mutex);
1771 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1773 mutex_unlock(&sfp->f_mutex);
1777 mutex_unlock(&sfp->f_mutex);
1779 md->pages = req_schp->pages;
1780 md->page_order = req_schp->page_order;
1781 md->nr_entries = req_schp->k_use_sg;
1783 md->null_mapped = hp->dxferp ? 0 : 1;
1784 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1791 struct iovec *iov = NULL;
1794 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1798 iov_iter_truncate(&i, hp->dxfer_len);
1799 if (!iov_iter_count(&i)) {
1804 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1807 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1808 hp->dxfer_len, GFP_ATOMIC);
1814 req_schp->dio_in_use = 1;
1815 hp->info |= SG_INFO_DIRECT_IO;
1822 sg_finish_rem_req(Sg_request *srp)
1826 Sg_fd *sfp = srp->parentfp;
1827 Sg_scatter_hold *req_schp = &srp->data;
1829 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1830 "sg_finish_rem_req: res_used=%d\n",
1831 (int) srp->res_used));
1833 ret = blk_rq_unmap_user(srp->bio);
1836 scsi_req_free_cmd(scsi_req(srp->rq));
1837 blk_put_request(srp->rq);
1841 sg_unlink_reserve(sfp, srp);
1843 sg_remove_scat(sfp, req_schp);
1849 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1851 int sg_bufflen = tablesize * sizeof(struct page *);
1852 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1854 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1857 schp->sglist_len = sg_bufflen;
1858 return tablesize; /* number of scat_gath elements allocated */
1862 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1864 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1865 int sg_tablesize = sfp->parentdp->sg_tablesize;
1866 int blk_size = buff_size, order;
1867 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1868 struct sg_device *sdp = sfp->parentdp;
1873 ++blk_size; /* don't know why */
1874 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1875 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1876 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1877 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1878 buff_size, blk_size));
1880 /* N.B. ret_sz carried into this block ... */
1881 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1882 if (mx_sc_elems < 0)
1883 return mx_sc_elems; /* most likely -ENOMEM */
1885 num = scatter_elem_sz;
1886 if (unlikely(num != scatter_elem_sz_prev)) {
1887 if (num < PAGE_SIZE) {
1888 scatter_elem_sz = PAGE_SIZE;
1889 scatter_elem_sz_prev = PAGE_SIZE;
1891 scatter_elem_sz_prev = num;
1894 if (sdp->device->host->unchecked_isa_dma)
1895 gfp_mask |= GFP_DMA;
1897 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1898 gfp_mask |= __GFP_ZERO;
1900 order = get_order(num);
1902 ret_sz = 1 << (PAGE_SHIFT + order);
1904 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1905 k++, rem_sz -= ret_sz) {
1907 num = (rem_sz > scatter_elem_sz_prev) ?
1908 scatter_elem_sz_prev : rem_sz;
1910 schp->pages[k] = alloc_pages(gfp_mask, order);
1911 if (!schp->pages[k])
1914 if (num == scatter_elem_sz_prev) {
1915 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1916 scatter_elem_sz = ret_sz;
1917 scatter_elem_sz_prev = ret_sz;
1921 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1922 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1924 } /* end of for loop */
1926 schp->page_order = order;
1928 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1929 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1932 schp->bufflen = blk_size;
1933 if (rem_sz > 0) /* must have failed */
1937 for (i = 0; i < k; i++)
1938 __free_pages(schp->pages[i], order);
1947 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1949 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1950 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1951 if (schp->pages && schp->sglist_len > 0) {
1952 if (!schp->dio_in_use) {
1955 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1957 sg_printk(KERN_INFO, sfp->parentdp,
1958 "sg_remove_scat: k=%d, pg=0x%p\n",
1959 k, schp->pages[k]));
1960 __free_pages(schp->pages[k], schp->page_order);
1966 memset(schp, 0, sizeof (*schp));
1970 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1972 Sg_scatter_hold *schp = &srp->data;
1975 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1976 "sg_read_oxfer: num_read_xfer=%d\n",
1978 if ((!outp) || (num_read_xfer <= 0))
1981 num = 1 << (PAGE_SHIFT + schp->page_order);
1982 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1983 if (num > num_read_xfer) {
1984 if (__copy_to_user(outp, page_address(schp->pages[k]),
1989 if (__copy_to_user(outp, page_address(schp->pages[k]),
1992 num_read_xfer -= num;
1993 if (num_read_xfer <= 0)
2003 sg_build_reserve(Sg_fd * sfp, int req_size)
2005 Sg_scatter_hold *schp = &sfp->reserve;
2007 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2008 "sg_build_reserve: req_size=%d\n", req_size));
2010 if (req_size < PAGE_SIZE)
2011 req_size = PAGE_SIZE;
2012 if (0 == sg_build_indirect(schp, sfp, req_size))
2015 sg_remove_scat(sfp, schp);
2016 req_size >>= 1; /* divide by 2 */
2017 } while (req_size > (PAGE_SIZE / 2));
2021 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2023 Sg_scatter_hold *req_schp = &srp->data;
2024 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2028 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2029 "sg_link_reserve: size=%d\n", size));
2032 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2033 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2035 req_schp->k_use_sg = k + 1;
2036 req_schp->sglist_len = rsv_schp->sglist_len;
2037 req_schp->pages = rsv_schp->pages;
2039 req_schp->bufflen = size;
2040 req_schp->page_order = rsv_schp->page_order;
2046 if (k >= rsv_schp->k_use_sg)
2047 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2048 "sg_link_reserve: BAD size\n"));
2052 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2054 Sg_scatter_hold *req_schp = &srp->data;
2056 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2057 "sg_unlink_reserve: req->k_use_sg=%d\n",
2058 (int) req_schp->k_use_sg));
2059 req_schp->k_use_sg = 0;
2060 req_schp->bufflen = 0;
2061 req_schp->pages = NULL;
2062 req_schp->page_order = 0;
2063 req_schp->sglist_len = 0;
2065 /* Called without mutex lock to avoid deadlock */
2066 sfp->res_in_use = 0;
2070 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2073 unsigned long iflags;
2075 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2076 list_for_each_entry(resp, &sfp->rq_list, entry) {
2077 /* look for requests that are ready + not SG_IO owned */
2078 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2079 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2080 resp->done = 2; /* guard against other readers */
2081 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2085 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2089 /* always adds to end of list */
2091 sg_add_request(Sg_fd * sfp)
2094 unsigned long iflags;
2095 Sg_request *rp = sfp->req_arr;
2097 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2098 if (!list_empty(&sfp->rq_list)) {
2102 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2106 if (k >= SG_MAX_QUEUE)
2109 memset(rp, 0, sizeof (Sg_request));
2111 rp->header.duration = jiffies_to_msecs(jiffies);
2112 list_add_tail(&rp->entry, &sfp->rq_list);
2113 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2116 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2120 /* Return of 1 for found; 0 for not found */
2122 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2124 unsigned long iflags;
2127 if (!sfp || !srp || list_empty(&sfp->rq_list))
2129 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2130 if (!list_empty(&srp->entry)) {
2131 list_del(&srp->entry);
2132 srp->parentfp = NULL;
2135 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2140 sg_add_sfp(Sg_device * sdp)
2143 unsigned long iflags;
2146 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2148 return ERR_PTR(-ENOMEM);
2150 init_waitqueue_head(&sfp->read_wait);
2151 rwlock_init(&sfp->rq_list_lock);
2152 INIT_LIST_HEAD(&sfp->rq_list);
2153 kref_init(&sfp->f_ref);
2154 mutex_init(&sfp->f_mutex);
2155 sfp->timeout = SG_DEFAULT_TIMEOUT;
2156 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2157 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2158 sfp->cmd_q = SG_DEF_COMMAND_Q;
2159 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2160 sfp->parentdp = sdp;
2161 write_lock_irqsave(&sdp->sfd_lock, iflags);
2162 if (atomic_read(&sdp->detaching)) {
2163 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2164 return ERR_PTR(-ENODEV);
2166 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2167 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2168 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2169 "sg_add_sfp: sfp=0x%p\n", sfp));
2170 if (unlikely(sg_big_buff != def_reserved_size))
2171 sg_big_buff = def_reserved_size;
2173 bufflen = min_t(int, sg_big_buff,
2174 max_sectors_bytes(sdp->device->request_queue));
2175 sg_build_reserve(sfp, bufflen);
2176 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2177 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2178 sfp->reserve.bufflen,
2179 sfp->reserve.k_use_sg));
2181 kref_get(&sdp->d_ref);
2182 __module_get(THIS_MODULE);
2187 sg_remove_sfp_usercontext(struct work_struct *work)
2189 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2190 struct sg_device *sdp = sfp->parentdp;
2192 unsigned long iflags;
2194 /* Cleanup any responses which were never read(). */
2195 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2196 while (!list_empty(&sfp->rq_list)) {
2197 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2198 sg_finish_rem_req(srp);
2199 list_del(&srp->entry);
2200 srp->parentfp = NULL;
2202 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2204 if (sfp->reserve.bufflen > 0) {
2205 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2206 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2207 (int) sfp->reserve.bufflen,
2208 (int) sfp->reserve.k_use_sg));
2209 sg_remove_scat(sfp, &sfp->reserve);
2212 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2213 "sg_remove_sfp: sfp=0x%p\n", sfp));
2216 scsi_device_put(sdp->device);
2217 kref_put(&sdp->d_ref, sg_device_destroy);
2218 module_put(THIS_MODULE);
2222 sg_remove_sfp(struct kref *kref)
2224 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2225 struct sg_device *sdp = sfp->parentdp;
2226 unsigned long iflags;
2228 write_lock_irqsave(&sdp->sfd_lock, iflags);
2229 list_del(&sfp->sfd_siblings);
2230 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2232 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2233 schedule_work(&sfp->ew.work);
2236 #ifdef CONFIG_SCSI_PROC_FS
2238 sg_idr_max_id(int id, void *p, void *data)
2252 unsigned long iflags;
2254 read_lock_irqsave(&sg_index_lock, iflags);
2255 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2256 read_unlock_irqrestore(&sg_index_lock, iflags);
2257 return k + 1; /* origin 1 */
2261 /* must be called with sg_index_lock held */
2262 static Sg_device *sg_lookup_dev(int dev)
2264 return idr_find(&sg_index_idr, dev);
2270 struct sg_device *sdp;
2271 unsigned long flags;
2273 read_lock_irqsave(&sg_index_lock, flags);
2274 sdp = sg_lookup_dev(dev);
2276 sdp = ERR_PTR(-ENXIO);
2277 else if (atomic_read(&sdp->detaching)) {
2278 /* If sdp->detaching, then the refcount may already be 0, in
2279 * which case it would be a bug to do kref_get().
2281 sdp = ERR_PTR(-ENODEV);
2283 kref_get(&sdp->d_ref);
2284 read_unlock_irqrestore(&sg_index_lock, flags);
2289 #ifdef CONFIG_SCSI_PROC_FS
2291 static struct proc_dir_entry *sg_proc_sgp = NULL;
2293 static char sg_proc_sg_dirname[] = "scsi/sg";
2295 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2297 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2298 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2299 size_t count, loff_t *off);
2300 static const struct file_operations adio_fops = {
2301 .owner = THIS_MODULE,
2302 .open = sg_proc_single_open_adio,
2304 .llseek = seq_lseek,
2305 .write = sg_proc_write_adio,
2306 .release = single_release,
2309 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2310 static ssize_t sg_proc_write_dressz(struct file *filp,
2311 const char __user *buffer, size_t count, loff_t *off);
2312 static const struct file_operations dressz_fops = {
2313 .owner = THIS_MODULE,
2314 .open = sg_proc_single_open_dressz,
2316 .llseek = seq_lseek,
2317 .write = sg_proc_write_dressz,
2318 .release = single_release,
2321 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2322 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2323 static const struct file_operations version_fops = {
2324 .owner = THIS_MODULE,
2325 .open = sg_proc_single_open_version,
2327 .llseek = seq_lseek,
2328 .release = single_release,
2331 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2332 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2333 static const struct file_operations devhdr_fops = {
2334 .owner = THIS_MODULE,
2335 .open = sg_proc_single_open_devhdr,
2337 .llseek = seq_lseek,
2338 .release = single_release,
2341 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2342 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2343 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2344 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2345 static void dev_seq_stop(struct seq_file *s, void *v);
2346 static const struct file_operations dev_fops = {
2347 .owner = THIS_MODULE,
2348 .open = sg_proc_open_dev,
2350 .llseek = seq_lseek,
2351 .release = seq_release,
2353 static const struct seq_operations dev_seq_ops = {
2354 .start = dev_seq_start,
2355 .next = dev_seq_next,
2356 .stop = dev_seq_stop,
2357 .show = sg_proc_seq_show_dev,
2360 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2361 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2362 static const struct file_operations devstrs_fops = {
2363 .owner = THIS_MODULE,
2364 .open = sg_proc_open_devstrs,
2366 .llseek = seq_lseek,
2367 .release = seq_release,
2369 static const struct seq_operations devstrs_seq_ops = {
2370 .start = dev_seq_start,
2371 .next = dev_seq_next,
2372 .stop = dev_seq_stop,
2373 .show = sg_proc_seq_show_devstrs,
2376 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2377 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2378 static const struct file_operations debug_fops = {
2379 .owner = THIS_MODULE,
2380 .open = sg_proc_open_debug,
2382 .llseek = seq_lseek,
2383 .release = seq_release,
2385 static const struct seq_operations debug_seq_ops = {
2386 .start = dev_seq_start,
2387 .next = dev_seq_next,
2388 .stop = dev_seq_stop,
2389 .show = sg_proc_seq_show_debug,
2393 struct sg_proc_leaf {
2395 const struct file_operations * fops;
2398 static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2399 {"allow_dio", &adio_fops},
2400 {"debug", &debug_fops},
2401 {"def_reserved_size", &dressz_fops},
2402 {"device_hdr", &devhdr_fops},
2403 {"devices", &dev_fops},
2404 {"device_strs", &devstrs_fops},
2405 {"version", &version_fops}
2411 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2414 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2417 for (k = 0; k < num_leaves; ++k) {
2418 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2419 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2420 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2426 sg_proc_cleanup(void)
2429 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2433 for (k = 0; k < num_leaves; ++k)
2434 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2435 remove_proc_entry(sg_proc_sg_dirname, NULL);
2439 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2441 seq_printf(s, "%d\n", *((int *)s->private));
2445 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2447 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2451 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2452 size_t count, loff_t *off)
2457 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2459 err = kstrtoul_from_user(buffer, count, 0, &num);
2462 sg_allow_dio = num ? 1 : 0;
2466 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2468 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2472 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2473 size_t count, loff_t *off)
2476 unsigned long k = ULONG_MAX;
2478 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2481 err = kstrtoul_from_user(buffer, count, 0, &k);
2484 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2491 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2493 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2498 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2500 return single_open(file, sg_proc_seq_show_version, NULL);
2503 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2505 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2509 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2511 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2514 struct sg_proc_deviter {
2519 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2521 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2528 it->max = sg_last_dev();
2529 if (it->index >= it->max)
2534 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2536 struct sg_proc_deviter * it = s->private;
2539 return (it->index < it->max) ? it : NULL;
2542 static void dev_seq_stop(struct seq_file *s, void *v)
2547 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2549 return seq_open(file, &dev_seq_ops);
2552 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2554 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2556 struct scsi_device *scsidp;
2557 unsigned long iflags;
2559 read_lock_irqsave(&sg_index_lock, iflags);
2560 sdp = it ? sg_lookup_dev(it->index) : NULL;
2561 if ((NULL == sdp) || (NULL == sdp->device) ||
2562 (atomic_read(&sdp->detaching)))
2563 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2565 scsidp = sdp->device;
2566 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2567 scsidp->host->host_no, scsidp->channel,
2568 scsidp->id, scsidp->lun, (int) scsidp->type,
2570 (int) scsidp->queue_depth,
2571 (int) atomic_read(&scsidp->device_busy),
2572 (int) scsi_device_online(scsidp));
2574 read_unlock_irqrestore(&sg_index_lock, iflags);
2578 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2580 return seq_open(file, &devstrs_seq_ops);
2583 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2585 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2587 struct scsi_device *scsidp;
2588 unsigned long iflags;
2590 read_lock_irqsave(&sg_index_lock, iflags);
2591 sdp = it ? sg_lookup_dev(it->index) : NULL;
2592 scsidp = sdp ? sdp->device : NULL;
2593 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2594 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2595 scsidp->vendor, scsidp->model, scsidp->rev);
2597 seq_puts(s, "<no active device>\n");
2598 read_unlock_irqrestore(&sg_index_lock, iflags);
2602 /* must be called while holding sg_index_lock */
2603 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2605 int k, new_interface, blen, usg;
2608 const sg_io_hdr_t *hp;
2613 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2615 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2616 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2617 "(res)sgat=%d low_dma=%d\n", k,
2618 jiffies_to_msecs(fp->timeout),
2619 fp->reserve.bufflen,
2620 (int) fp->reserve.k_use_sg,
2621 (int) sdp->device->host->unchecked_isa_dma);
2622 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2623 (int) fp->cmd_q, (int) fp->force_packid,
2624 (int) fp->keep_orphan);
2625 list_for_each_entry(srp, &fp->rq_list, entry) {
2627 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2628 if (srp->res_used) {
2629 if (new_interface &&
2630 (SG_FLAG_MMAP_IO & hp->flags))
2635 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2641 blen = srp->data.bufflen;
2642 usg = srp->data.k_use_sg;
2643 seq_puts(s, srp->done ?
2644 ((1 == srp->done) ? "rcv:" : "fin:")
2646 seq_printf(s, " id=%d blen=%d",
2647 srp->header.pack_id, blen);
2649 seq_printf(s, " dur=%d", hp->duration);
2651 ms = jiffies_to_msecs(jiffies);
2652 seq_printf(s, " t_o/elap=%d/%d",
2653 (new_interface ? hp->timeout :
2654 jiffies_to_msecs(fp->timeout)),
2655 (ms > hp->duration ? ms - hp->duration : 0));
2657 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2658 (int) srp->data.cmd_opcode);
2660 if (list_empty(&fp->rq_list))
2661 seq_puts(s, " No requests active\n");
2662 read_unlock(&fp->rq_list_lock);
2666 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2668 return seq_open(file, &debug_seq_ops);
2671 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2673 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2675 unsigned long iflags;
2677 if (it && (0 == it->index))
2678 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2679 (int)it->max, sg_big_buff);
2681 read_lock_irqsave(&sg_index_lock, iflags);
2682 sdp = it ? sg_lookup_dev(it->index) : NULL;
2685 read_lock(&sdp->sfd_lock);
2686 if (!list_empty(&sdp->sfds)) {
2687 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2688 if (atomic_read(&sdp->detaching))
2689 seq_puts(s, "detaching pending close ");
2690 else if (sdp->device) {
2691 struct scsi_device *scsidp = sdp->device;
2693 seq_printf(s, "%d:%d:%d:%llu em=%d",
2694 scsidp->host->host_no,
2695 scsidp->channel, scsidp->id,
2697 scsidp->host->hostt->emulated);
2699 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2700 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2701 sg_proc_debug_helper(s, sdp);
2703 read_unlock(&sdp->sfd_lock);
2705 read_unlock_irqrestore(&sg_index_lock, iflags);
2709 #endif /* CONFIG_SCSI_PROC_FS */
2711 module_init(init_sg);
2712 module_exit(exit_sg);