1 // SPDX-License-Identifier: GPL-2.0-or-later
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
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
14 static int sg_version_num = 30536; /* 2 digits for each component */
15 #define SG_VERSION_STR "3.5.36"
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).
24 #include <linux/module.h>
27 #include <linux/kernel.h>
28 #include <linux/sched.h>
29 #include <linux/string.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() */
52 #include <scsi/scsi_dbg.h>
53 #include <scsi/scsi_host.h>
54 #include <scsi/scsi_driver.h>
55 #include <scsi/scsi_ioctl.h>
58 #include "scsi_logging.h"
60 #ifdef CONFIG_SCSI_PROC_FS
61 #include <linux/proc_fs.h>
62 static char *sg_version_date = "20140603";
64 static int sg_proc_init(void);
67 #define SG_ALLOW_DIO_DEF 0
69 #define SG_MAX_DEVS 32768
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
75 #define SG_MAX_CDB_SIZE 252
77 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
79 int 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).] */
86 static int def_reserved_size = -1; /* picks up init parameter */
87 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
89 static int scatter_elem_sz = SG_SCATTER_SZ;
90 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
92 #define SG_SECTOR_SZ 512
94 static int sg_add_device(struct device *, struct class_interface *);
95 static void sg_remove_device(struct device *, struct class_interface *);
97 static DEFINE_IDR(sg_index_idr);
98 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
99 file descriptor list for device */
101 static struct class_interface sg_interface = {
102 .add_dev = sg_add_device,
103 .remove_dev = sg_remove_device,
106 typedef 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 */
112 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
113 unsigned char cmd_opcode; /* first byte of command */
116 struct sg_device; /* forward declarations */
119 typedef 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 */
132 struct execute_work ew;
135 typedef 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 */
154 struct execute_work ew;
157 typedef 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 char name[DISK_NAME_LEN];
170 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
174 /* tasklet or soft irq callback */
175 static void sg_rq_end_io(struct request *rq, blk_status_t status);
176 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
177 static int sg_finish_rem_req(Sg_request * srp);
178 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
179 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
181 static 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);
184 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
185 unsigned char *cmnd, int timeout, int blocking);
186 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
187 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
188 static void sg_build_reserve(Sg_fd * sfp, int req_size);
189 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
190 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
191 static Sg_fd *sg_add_sfp(Sg_device * sdp);
192 static void sg_remove_sfp(struct kref *);
193 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
194 static Sg_request *sg_add_request(Sg_fd * sfp);
195 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
196 static Sg_device *sg_get_dev(int dev);
197 static void sg_device_destroy(struct kref *kref);
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)
204 #define sg_printk(prefix, sdp, fmt, a...) \
205 sdev_prefix_printk(prefix, (sdp)->device, (sdp)->name, fmt, ##a)
208 * The SCSI interfaces that use read() and write() as an asynchronous variant of
209 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
210 * to trigger read() and write() calls from various contexts with elevated
211 * privileges. This can lead to kernel memory corruption (e.g. if these
212 * interfaces are called through splice()) and privilege escalation inside
213 * userspace (e.g. if a process with access to such a device passes a file
214 * descriptor to a SUID binary as stdin/stdout/stderr).
216 * This function provides protection for the legacy API by restricting the
219 static int sg_check_file_access(struct file *filp, const char *caller)
221 if (filp->f_cred != current_real_cred()) {
222 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
223 caller, task_tgid_vnr(current), current->comm);
226 if (uaccess_kernel()) {
227 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
228 caller, task_tgid_vnr(current), current->comm);
234 static int sg_allow_access(struct file *filp, unsigned char *cmd)
236 struct sg_fd *sfp = filp->private_data;
238 if (sfp->parentdp->device->type == TYPE_SCANNER)
241 return blk_verify_command(cmd, filp->f_mode);
245 open_wait(Sg_device *sdp, int flags)
249 if (flags & O_EXCL) {
250 while (sdp->open_cnt > 0) {
251 mutex_unlock(&sdp->open_rel_lock);
252 retval = wait_event_interruptible(sdp->open_wait,
253 (atomic_read(&sdp->detaching) ||
255 mutex_lock(&sdp->open_rel_lock);
257 if (retval) /* -ERESTARTSYS */
259 if (atomic_read(&sdp->detaching))
263 while (sdp->exclude) {
264 mutex_unlock(&sdp->open_rel_lock);
265 retval = wait_event_interruptible(sdp->open_wait,
266 (atomic_read(&sdp->detaching) ||
268 mutex_lock(&sdp->open_rel_lock);
270 if (retval) /* -ERESTARTSYS */
272 if (atomic_read(&sdp->detaching))
280 /* Returns 0 on success, else a negated errno value */
282 sg_open(struct inode *inode, struct file *filp)
284 int dev = iminor(inode);
285 int flags = filp->f_flags;
286 struct request_queue *q;
291 nonseekable_open(inode, filp);
292 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
293 return -EPERM; /* Can't lock it with read only access */
294 sdp = sg_get_dev(dev);
298 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
299 "sg_open: flags=0x%x\n", flags));
301 /* This driver's module count bumped by fops_get in <linux/fs.h> */
302 /* Prevent the device driver from vanishing while we sleep */
303 retval = scsi_device_get(sdp->device);
307 retval = scsi_autopm_get_device(sdp->device);
311 /* scsi_block_when_processing_errors() may block so bypass
312 * check if O_NONBLOCK. Permits SCSI commands to be issued
313 * during error recovery. Tread carefully. */
314 if (!((flags & O_NONBLOCK) ||
315 scsi_block_when_processing_errors(sdp->device))) {
317 /* we are in error recovery for this device */
321 mutex_lock(&sdp->open_rel_lock);
322 if (flags & O_NONBLOCK) {
323 if (flags & O_EXCL) {
324 if (sdp->open_cnt > 0) {
326 goto error_mutex_locked;
331 goto error_mutex_locked;
335 retval = open_wait(sdp, flags);
336 if (retval) /* -ERESTARTSYS or -ENODEV */
337 goto error_mutex_locked;
340 /* N.B. at this point we are holding the open_rel_lock */
344 if (sdp->open_cnt < 1) { /* no existing opens */
346 q = sdp->device->request_queue;
347 sdp->sg_tablesize = queue_max_segments(q);
349 sfp = sg_add_sfp(sdp);
351 retval = PTR_ERR(sfp);
355 filp->private_data = sfp;
357 mutex_unlock(&sdp->open_rel_lock);
361 kref_put(&sdp->d_ref, sg_device_destroy);
365 if (flags & O_EXCL) {
366 sdp->exclude = false; /* undo if error */
367 wake_up_interruptible(&sdp->open_wait);
370 mutex_unlock(&sdp->open_rel_lock);
372 scsi_autopm_put_device(sdp->device);
374 scsi_device_put(sdp->device);
378 /* Release resources associated with a successful sg_open()
379 * Returns 0 on success, else a negated errno value */
381 sg_release(struct inode *inode, struct file *filp)
386 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
388 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
390 mutex_lock(&sdp->open_rel_lock);
391 scsi_autopm_put_device(sdp->device);
392 kref_put(&sfp->f_ref, sg_remove_sfp);
395 /* possibly many open()s waiting on exlude clearing, start many;
396 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
398 sdp->exclude = false;
399 wake_up_interruptible_all(&sdp->open_wait);
400 } else if (0 == sdp->open_cnt) {
401 wake_up_interruptible(&sdp->open_wait);
403 mutex_unlock(&sdp->open_rel_lock);
407 static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count)
409 struct sg_header __user *old_hdr = buf;
412 if (count >= SZ_SG_HEADER) {
413 /* negative reply_len means v3 format, otherwise v1/v2 */
414 if (get_user(reply_len, &old_hdr->reply_len))
418 return get_user(*pack_id, &old_hdr->pack_id);
420 if (in_compat_syscall() &&
421 count >= sizeof(struct compat_sg_io_hdr)) {
422 struct compat_sg_io_hdr __user *hp = buf;
424 return get_user(*pack_id, &hp->pack_id);
427 if (count >= sizeof(struct sg_io_hdr)) {
428 struct sg_io_hdr __user *hp = buf;
430 return get_user(*pack_id, &hp->pack_id);
434 /* no valid header was passed, so ignore the pack_id */
440 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
445 int req_pack_id = -1;
447 struct sg_header *old_hdr;
451 * This could cause a response to be stranded. Close the associated
452 * file descriptor to free up any resources being held.
454 retval = sg_check_file_access(filp, __func__);
458 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
460 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
461 "sg_read: count=%d\n", (int) count));
463 if (sfp->force_packid)
464 retval = get_sg_io_pack_id(&req_pack_id, buf, count);
468 srp = sg_get_rq_mark(sfp, req_pack_id);
469 if (!srp) { /* now wait on packet to arrive */
470 if (atomic_read(&sdp->detaching))
472 if (filp->f_flags & O_NONBLOCK)
474 retval = wait_event_interruptible(sfp->read_wait,
475 (atomic_read(&sdp->detaching) ||
476 (srp = sg_get_rq_mark(sfp, req_pack_id))));
477 if (atomic_read(&sdp->detaching))
480 /* -ERESTARTSYS as signal hit process */
483 if (srp->header.interface_id != '\0')
484 return sg_new_read(sfp, buf, count, srp);
487 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL);
491 old_hdr->reply_len = (int) hp->timeout;
492 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
493 old_hdr->pack_id = hp->pack_id;
494 old_hdr->twelve_byte =
495 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
496 old_hdr->target_status = hp->masked_status;
497 old_hdr->host_status = hp->host_status;
498 old_hdr->driver_status = hp->driver_status;
499 if ((CHECK_CONDITION & hp->masked_status) ||
500 (srp->sense_b[0] & 0x70) == 0x70) {
501 old_hdr->driver_status = DRIVER_SENSE;
502 memcpy(old_hdr->sense_buffer, srp->sense_b,
503 sizeof (old_hdr->sense_buffer));
505 switch (hp->host_status) {
506 /* This setup of 'result' is for backward compatibility and is best
507 ignored by the user who should use target, host + driver status */
509 case DID_PASSTHROUGH:
516 old_hdr->result = EBUSY;
523 old_hdr->result = EIO;
526 old_hdr->result = (srp->sense_b[0] == 0 &&
527 hp->masked_status == GOOD) ? 0 : EIO;
530 old_hdr->result = EIO;
534 /* Now copy the result back to the user buffer. */
535 if (count >= SZ_SG_HEADER) {
536 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
541 if (count > old_hdr->reply_len)
542 count = old_hdr->reply_len;
543 if (count > SZ_SG_HEADER) {
544 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
550 count = (old_hdr->result == 0) ? 0 : -EIO;
551 sg_finish_rem_req(srp);
552 sg_remove_request(sfp, srp);
560 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
562 sg_io_hdr_t *hp = &srp->header;
566 if (in_compat_syscall()) {
567 if (count < sizeof(struct compat_sg_io_hdr)) {
571 } else if (count < SZ_SG_IO_HDR) {
576 if ((hp->mx_sb_len > 0) && hp->sbp) {
577 if ((CHECK_CONDITION & hp->masked_status) ||
578 (srp->sense_b[0] & 0x70) == 0x70) {
579 int sb_len = SCSI_SENSE_BUFFERSIZE;
580 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
581 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
582 len = (len > sb_len) ? sb_len : len;
583 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
587 hp->driver_status = DRIVER_SENSE;
591 if (hp->masked_status || hp->host_status || hp->driver_status)
592 hp->info |= SG_INFO_CHECK;
593 err = put_sg_io_hdr(hp, buf);
595 err2 = sg_finish_rem_req(srp);
596 sg_remove_request(sfp, srp);
597 return err ? : err2 ? : count;
601 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
603 int mxsize, cmd_size, k;
604 int input_size, blocking;
605 unsigned char opcode;
609 struct sg_header old_hdr;
611 unsigned char cmnd[SG_MAX_CDB_SIZE];
614 retval = sg_check_file_access(filp, __func__);
618 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
620 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
621 "sg_write: count=%d\n", (int) count));
622 if (atomic_read(&sdp->detaching))
624 if (!((filp->f_flags & O_NONBLOCK) ||
625 scsi_block_when_processing_errors(sdp->device)))
628 if (count < SZ_SG_HEADER)
630 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
632 blocking = !(filp->f_flags & O_NONBLOCK);
633 if (old_hdr.reply_len < 0)
634 return sg_new_write(sfp, filp, buf, count,
635 blocking, 0, 0, NULL);
636 if (count < (SZ_SG_HEADER + 6))
637 return -EIO; /* The minimum scsi command length is 6 bytes. */
640 if (get_user(opcode, buf))
643 if (!(srp = sg_add_request(sfp))) {
644 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
645 "sg_write: queue full\n"));
648 mutex_lock(&sfp->f_mutex);
649 if (sfp->next_cmd_len > 0) {
650 cmd_size = sfp->next_cmd_len;
651 sfp->next_cmd_len = 0; /* reset so only this write() effected */
653 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
654 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
657 mutex_unlock(&sfp->f_mutex);
658 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
659 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
660 /* Determine buffer size. */
661 input_size = count - cmd_size;
662 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
663 mxsize -= SZ_SG_HEADER;
664 input_size -= SZ_SG_HEADER;
665 if (input_size < 0) {
666 sg_remove_request(sfp, srp);
667 return -EIO; /* User did not pass enough bytes for this command. */
670 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
671 hp->cmd_len = (unsigned char) cmd_size;
675 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
676 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
678 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
679 hp->dxfer_len = mxsize;
680 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
681 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
682 hp->dxferp = (char __user *)buf + cmd_size;
686 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
687 hp->flags = input_size; /* structure abuse ... */
688 hp->pack_id = old_hdr.pack_id;
690 if (copy_from_user(cmnd, buf, cmd_size)) {
691 sg_remove_request(sfp, srp);
695 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
696 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
697 * is a non-zero input_size, so emit a warning.
699 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
700 printk_ratelimited(KERN_WARNING
701 "sg_write: data in/out %d/%d bytes "
702 "for SCSI command 0x%x-- guessing "
703 "data in;\n program %s not setting "
704 "count and/or reply_len properly\n",
705 old_hdr.reply_len - (int)SZ_SG_HEADER,
706 input_size, (unsigned int) cmnd[0],
709 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
710 return (k < 0) ? k : count;
714 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
715 size_t count, int blocking, int read_only, int sg_io_owned,
721 unsigned char cmnd[SG_MAX_CDB_SIZE];
723 unsigned long ul_timeout;
725 if (count < SZ_SG_IO_HDR)
728 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
729 if (!(srp = sg_add_request(sfp))) {
730 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
731 "sg_new_write: queue full\n"));
734 srp->sg_io_owned = sg_io_owned;
736 if (get_sg_io_hdr(hp, buf)) {
737 sg_remove_request(sfp, srp);
740 if (hp->interface_id != 'S') {
741 sg_remove_request(sfp, srp);
744 if (hp->flags & SG_FLAG_MMAP_IO) {
745 if (hp->dxfer_len > sfp->reserve.bufflen) {
746 sg_remove_request(sfp, srp);
747 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
749 if (hp->flags & SG_FLAG_DIRECT_IO) {
750 sg_remove_request(sfp, srp);
751 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
753 if (sfp->res_in_use) {
754 sg_remove_request(sfp, srp);
755 return -EBUSY; /* reserve buffer already being used */
758 ul_timeout = msecs_to_jiffies(srp->header.timeout);
759 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
760 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
761 sg_remove_request(sfp, srp);
764 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
765 sg_remove_request(sfp, srp);
768 if (read_only && sg_allow_access(file, cmnd)) {
769 sg_remove_request(sfp, srp);
772 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
781 sg_common_write(Sg_fd * sfp, Sg_request * srp,
782 unsigned char *cmnd, int timeout, int blocking)
785 Sg_device *sdp = sfp->parentdp;
786 sg_io_hdr_t *hp = &srp->header;
788 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
790 hp->masked_status = 0;
794 hp->driver_status = 0;
796 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
797 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
798 (int) cmnd[0], (int) hp->cmd_len));
800 if (hp->dxfer_len >= SZ_256M) {
801 sg_remove_request(sfp, srp);
805 k = sg_start_req(srp, cmnd);
807 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
808 "sg_common_write: start_req err=%d\n", k));
809 sg_finish_rem_req(srp);
810 sg_remove_request(sfp, srp);
811 return k; /* probably out of space --> ENOMEM */
813 if (atomic_read(&sdp->detaching)) {
815 scsi_req_free_cmd(scsi_req(srp->rq));
816 blk_put_request(srp->rq);
820 sg_finish_rem_req(srp);
821 sg_remove_request(sfp, srp);
825 hp->duration = jiffies_to_msecs(jiffies);
826 if (hp->interface_id != '\0' && /* v3 (or later) interface */
827 (SG_FLAG_Q_AT_TAIL & hp->flags))
832 srp->rq->timeout = timeout;
833 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
834 blk_execute_rq_nowait(NULL, srp->rq, at_head, sg_rq_end_io);
838 static int srp_done(Sg_fd *sfp, Sg_request *srp)
843 read_lock_irqsave(&sfp->rq_list_lock, flags);
845 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
849 static int max_sectors_bytes(struct request_queue *q)
851 unsigned int max_sectors = queue_max_sectors(q);
853 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
855 return max_sectors << 9;
859 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
866 list_for_each_entry(srp, &sfp->rq_list, entry) {
867 if (val >= SG_MAX_QUEUE)
869 rinfo[val].req_state = srp->done + 1;
871 srp->header.masked_status &
872 srp->header.host_status &
873 srp->header.driver_status;
875 rinfo[val].duration =
876 srp->header.duration;
878 ms = jiffies_to_msecs(jiffies);
879 rinfo[val].duration =
880 (ms > srp->header.duration) ?
881 (ms - srp->header.duration) : 0;
883 rinfo[val].orphan = srp->orphan;
884 rinfo[val].sg_io_owned = srp->sg_io_owned;
885 rinfo[val].pack_id = srp->header.pack_id;
886 rinfo[val].usr_ptr = srp->header.usr_ptr;
892 struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
898 compat_uptr_t usr_ptr;
899 unsigned int duration;
903 static int put_compat_request_table(struct compat_sg_req_info __user *o,
904 struct sg_req_info *rinfo)
907 for (i = 0; i < SG_MAX_QUEUE; i++) {
908 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
909 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
910 put_user(rinfo[i].duration, &o[i].duration) ||
911 put_user(rinfo[i].unused, &o[i].unused))
919 sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
920 unsigned int cmd_in, void __user *p)
923 int result, val, read_only;
925 unsigned long iflags;
927 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
928 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
929 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
933 if (atomic_read(&sdp->detaching))
935 if (!scsi_block_when_processing_errors(sdp->device))
937 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
938 1, read_only, 1, &srp);
941 result = wait_event_interruptible(sfp->read_wait,
942 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
943 if (atomic_read(&sdp->detaching))
945 write_lock_irq(&sfp->rq_list_lock);
948 write_unlock_irq(&sfp->rq_list_lock);
949 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
950 return (result < 0) ? result : 0;
953 write_unlock_irq(&sfp->rq_list_lock);
954 return result; /* -ERESTARTSYS because signal hit process */
956 result = get_user(val, ip);
961 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
962 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
964 sfp->timeout_user = val;
965 sfp->timeout = mult_frac(val, HZ, USER_HZ);
968 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
969 /* strange ..., for backward compatibility */
970 return sfp->timeout_user;
971 case SG_SET_FORCE_LOW_DMA:
973 * N.B. This ioctl never worked properly, but failed to
974 * return an error value. So returning '0' to keep compability
975 * with legacy applications.
979 return put_user(0, ip);
984 if (atomic_read(&sdp->detaching))
986 memset(&v, 0, sizeof(v));
987 v.host_no = sdp->device->host->host_no;
988 v.channel = sdp->device->channel;
989 v.scsi_id = sdp->device->id;
990 v.lun = sdp->device->lun;
991 v.scsi_type = sdp->device->type;
992 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
993 v.d_queue_depth = sdp->device->queue_depth;
994 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
998 case SG_SET_FORCE_PACK_ID:
999 result = get_user(val, ip);
1002 sfp->force_packid = val ? 1 : 0;
1004 case SG_GET_PACK_ID:
1005 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1006 list_for_each_entry(srp, &sfp->rq_list, entry) {
1007 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1008 read_unlock_irqrestore(&sfp->rq_list_lock,
1010 return put_user(srp->header.pack_id, ip);
1013 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1014 return put_user(-1, ip);
1015 case SG_GET_NUM_WAITING:
1016 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1018 list_for_each_entry(srp, &sfp->rq_list, entry) {
1019 if ((1 == srp->done) && (!srp->sg_io_owned))
1022 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1023 return put_user(val, ip);
1024 case SG_GET_SG_TABLESIZE:
1025 return put_user(sdp->sg_tablesize, ip);
1026 case SG_SET_RESERVED_SIZE:
1027 result = get_user(val, ip);
1032 val = min_t(int, val,
1033 max_sectors_bytes(sdp->device->request_queue));
1034 mutex_lock(&sfp->f_mutex);
1035 if (val != sfp->reserve.bufflen) {
1036 if (sfp->mmap_called ||
1038 mutex_unlock(&sfp->f_mutex);
1042 sg_remove_scat(sfp, &sfp->reserve);
1043 sg_build_reserve(sfp, val);
1045 mutex_unlock(&sfp->f_mutex);
1047 case SG_GET_RESERVED_SIZE:
1048 val = min_t(int, sfp->reserve.bufflen,
1049 max_sectors_bytes(sdp->device->request_queue));
1050 return put_user(val, ip);
1051 case SG_SET_COMMAND_Q:
1052 result = get_user(val, ip);
1055 sfp->cmd_q = val ? 1 : 0;
1057 case SG_GET_COMMAND_Q:
1058 return put_user((int) sfp->cmd_q, ip);
1059 case SG_SET_KEEP_ORPHAN:
1060 result = get_user(val, ip);
1063 sfp->keep_orphan = val;
1065 case SG_GET_KEEP_ORPHAN:
1066 return put_user((int) sfp->keep_orphan, ip);
1067 case SG_NEXT_CMD_LEN:
1068 result = get_user(val, ip);
1071 if (val > SG_MAX_CDB_SIZE)
1073 sfp->next_cmd_len = (val > 0) ? val : 0;
1075 case SG_GET_VERSION_NUM:
1076 return put_user(sg_version_num, ip);
1077 case SG_GET_ACCESS_COUNT:
1078 /* faked - we don't have a real access count anymore */
1079 val = (sdp->device ? 1 : 0);
1080 return put_user(val, ip);
1081 case SG_GET_REQUEST_TABLE:
1083 sg_req_info_t *rinfo;
1085 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1089 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1090 sg_fill_request_table(sfp, rinfo);
1091 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1092 #ifdef CONFIG_COMPAT
1093 if (in_compat_syscall())
1094 result = put_compat_request_table(p, rinfo);
1097 result = copy_to_user(p, rinfo,
1098 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1099 result = result ? -EFAULT : 0;
1103 case SG_EMULATED_HOST:
1104 if (atomic_read(&sdp->detaching))
1106 return put_user(sdp->device->host->hostt->emulated, ip);
1107 case SCSI_IOCTL_SEND_COMMAND:
1108 if (atomic_read(&sdp->detaching))
1110 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1112 result = get_user(val, ip);
1115 sdp->sgdebug = (char) val;
1118 return put_user(max_sectors_bytes(sdp->device->request_queue),
1121 return blk_trace_setup(sdp->device->request_queue, sdp->name,
1122 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1125 return blk_trace_startstop(sdp->device->request_queue, 1);
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:
1135 if (atomic_read(&sdp->detaching))
1140 return -EPERM; /* don't know so take safe approach */
1144 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1145 cmd_in, filp->f_flags & O_NDELAY);
1149 return -ENOIOCTLCMD;
1153 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1155 void __user *p = (void __user *)arg;
1160 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1163 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1164 if (ret != -ENOIOCTLCMD)
1167 return scsi_ioctl(sdp->device, cmd_in, p);
1170 #ifdef CONFIG_COMPAT
1171 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1173 void __user *p = compat_ptr(arg);
1178 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1181 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1182 if (ret != -ENOIOCTLCMD)
1185 return scsi_compat_ioctl(sdp->device, cmd_in, p);
1190 sg_poll(struct file *filp, poll_table * wait)
1197 unsigned long iflags;
1199 sfp = filp->private_data;
1202 sdp = sfp->parentdp;
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;
1213 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1215 if (atomic_read(&sdp->detaching))
1217 else if (!sfp->cmd_q) {
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));
1228 sg_fasync(int fd, struct file *filp, int mode)
1233 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1235 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1236 "sg_fasync: mode=%d\n", mode));
1238 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1242 sg_vma_fault(struct vm_fault *vmf)
1244 struct vm_area_struct *vma = vmf->vma;
1246 unsigned long offset, len, sa;
1247 Sg_scatter_hold *rsv_schp;
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));
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;
1265 struct page *page = nth_page(rsv_schp->pages[k],
1266 offset >> PAGE_SHIFT);
1267 get_page(page); /* increment page count */
1269 return 0; /* success */
1275 return VM_FAULT_SIGBUS;
1278 static const struct vm_operations_struct sg_mmap_vm_ops = {
1279 .fault = sg_vma_fault,
1283 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1286 unsigned long req_sz, len, sa;
1287 Sg_scatter_hold *rsv_schp;
1291 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
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));
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 */
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;
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;
1319 mutex_unlock(&sfp->f_mutex);
1324 sg_rq_end_io_usercontext(struct work_struct *work)
1326 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1327 struct sg_fd *sfp = srp->parentfp;
1329 sg_finish_rem_req(srp);
1330 sg_remove_request(sfp, srp);
1331 kref_put(&sfp->f_ref, sg_remove_sfp);
1335 * This function is a "bottom half" handler that is called by the mid
1336 * level when a command is completed (or has failed).
1339 sg_rq_end_io(struct request *rq, blk_status_t status)
1341 struct sg_request *srp = rq->end_io_data;
1342 struct scsi_request *req = scsi_req(rq);
1345 unsigned long iflags;
1348 int result, resid, done = 1;
1350 if (WARN_ON(srp->done != 0))
1353 sfp = srp->parentfp;
1354 if (WARN_ON(sfp == NULL))
1357 sdp = sfp->parentdp;
1358 if (unlikely(atomic_read(&sdp->detaching)))
1359 pr_info("%s: device detaching\n", __func__);
1362 result = req->result;
1363 resid = req->resid_len;
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;
1373 struct scsi_sense_hdr sshdr;
1375 srp->header.status = 0xff & result;
1376 srp->header.masked_status = status_byte(result);
1377 srp->header.msg_status = COMMAND_COMPLETE;
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);
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;
1399 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1401 /* Rely on write phase to clean out srp status values, so no "else" */
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.
1410 scsi_req_free_cmd(scsi_req(rq));
1411 blk_put_request(rq);
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;
1421 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1424 /* Now wake up any sg_read() that is waiting for this
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);
1431 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1432 schedule_work(&srp->ew.work);
1436 static const struct file_operations sg_fops = {
1437 .owner = THIS_MODULE,
1441 .unlocked_ioctl = sg_ioctl,
1442 #ifdef CONFIG_COMPAT
1443 .compat_ioctl = sg_compat_ioctl,
1447 .release = sg_release,
1448 .fasync = sg_fasync,
1449 .llseek = no_llseek,
1452 static struct class *sg_sysfs_class;
1454 static int sg_sysfs_valid = 0;
1457 sg_alloc(struct scsi_device *scsidp)
1459 struct request_queue *q = scsidp->request_queue;
1461 unsigned long iflags;
1465 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1467 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1468 "failure\n", __func__);
1469 return ERR_PTR(-ENOMEM);
1472 idr_preload(GFP_KERNEL);
1473 write_lock_irqsave(&sg_index_lock, iflags);
1475 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
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);
1483 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1484 "allocation Sg_device failure: %d\n",
1491 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1492 "sg_alloc: dev=%d \n", k));
1493 sprintf(sdp->name, "sg%d", k);
1494 sdp->device = scsidp;
1495 mutex_init(&sdp->open_rel_lock);
1496 INIT_LIST_HEAD(&sdp->sfds);
1497 init_waitqueue_head(&sdp->open_wait);
1498 atomic_set(&sdp->detaching, 0);
1499 rwlock_init(&sdp->sfd_lock);
1500 sdp->sg_tablesize = queue_max_segments(q);
1502 kref_init(&sdp->d_ref);
1506 write_unlock_irqrestore(&sg_index_lock, iflags);
1511 return ERR_PTR(error);
1517 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1519 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1520 Sg_device *sdp = NULL;
1521 struct cdev * cdev = NULL;
1523 unsigned long iflags;
1526 cdev = cdev_alloc();
1528 pr_warn("%s: cdev_alloc failed\n", __func__);
1531 cdev->owner = THIS_MODULE;
1532 cdev->ops = &sg_fops;
1534 sdp = sg_alloc(scsidp);
1536 pr_warn("%s: sg_alloc failed\n", __func__);
1537 error = PTR_ERR(sdp);
1541 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1546 if (sg_sysfs_valid) {
1547 struct device *sg_class_member;
1549 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1550 MKDEV(SCSI_GENERIC_MAJOR,
1552 sdp, "%s", sdp->name);
1553 if (IS_ERR(sg_class_member)) {
1554 pr_err("%s: device_create failed\n", __func__);
1555 error = PTR_ERR(sg_class_member);
1558 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1559 &sg_class_member->kobj, "generic");
1561 pr_err("%s: unable to make symlink 'generic' back "
1562 "to sg%d\n", __func__, sdp->index);
1564 pr_warn("%s: sg_sys Invalid\n", __func__);
1566 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1567 "type %d\n", sdp->index, scsidp->type);
1569 dev_set_drvdata(cl_dev, sdp);
1574 write_lock_irqsave(&sg_index_lock, iflags);
1575 idr_remove(&sg_index_idr, sdp->index);
1576 write_unlock_irqrestore(&sg_index_lock, iflags);
1586 sg_device_destroy(struct kref *kref)
1588 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1589 unsigned long flags;
1591 /* CAUTION! Note that the device can still be found via idr_find()
1592 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1593 * any other cleanup.
1596 write_lock_irqsave(&sg_index_lock, flags);
1597 idr_remove(&sg_index_idr, sdp->index);
1598 write_unlock_irqrestore(&sg_index_lock, flags);
1601 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1607 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1609 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1610 Sg_device *sdp = dev_get_drvdata(cl_dev);
1611 unsigned long iflags;
1617 /* want sdp->detaching non-zero as soon as possible */
1618 val = atomic_inc_return(&sdp->detaching);
1620 return; /* only want to do following once per device */
1622 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1625 read_lock_irqsave(&sdp->sfd_lock, iflags);
1626 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1627 wake_up_interruptible_all(&sfp->read_wait);
1628 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1630 wake_up_interruptible_all(&sdp->open_wait);
1631 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1633 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1634 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1635 cdev_del(sdp->cdev);
1638 kref_put(&sdp->d_ref, sg_device_destroy);
1641 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1642 module_param_named(def_reserved_size, def_reserved_size, int,
1644 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1646 MODULE_AUTHOR("Douglas Gilbert");
1647 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1648 MODULE_LICENSE("GPL");
1649 MODULE_VERSION(SG_VERSION_STR);
1650 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1652 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1653 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1654 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1655 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1662 if (scatter_elem_sz < PAGE_SIZE) {
1663 scatter_elem_sz = PAGE_SIZE;
1664 scatter_elem_sz_prev = scatter_elem_sz;
1666 if (def_reserved_size >= 0)
1667 sg_big_buff = def_reserved_size;
1669 def_reserved_size = sg_big_buff;
1671 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1675 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1676 if ( IS_ERR(sg_sysfs_class) ) {
1677 rc = PTR_ERR(sg_sysfs_class);
1681 rc = scsi_register_interface(&sg_interface);
1683 #ifdef CONFIG_SCSI_PROC_FS
1685 #endif /* CONFIG_SCSI_PROC_FS */
1688 class_destroy(sg_sysfs_class);
1690 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1697 #ifdef CONFIG_SCSI_PROC_FS
1698 remove_proc_subtree("scsi/sg", NULL);
1699 #endif /* CONFIG_SCSI_PROC_FS */
1700 scsi_unregister_interface(&sg_interface);
1701 class_destroy(sg_sysfs_class);
1703 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1705 idr_destroy(&sg_index_idr);
1709 sg_start_req(Sg_request *srp, unsigned char *cmd)
1713 struct scsi_request *req;
1714 Sg_fd *sfp = srp->parentfp;
1715 sg_io_hdr_t *hp = &srp->header;
1716 int dxfer_len = (int) hp->dxfer_len;
1717 int dxfer_dir = hp->dxfer_direction;
1718 unsigned int iov_count = hp->iovec_count;
1719 Sg_scatter_hold *req_schp = &srp->data;
1720 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1721 struct request_queue *q = sfp->parentdp->device->request_queue;
1722 struct rq_map_data *md, map_data;
1723 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1724 unsigned char *long_cmdp = NULL;
1726 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1727 "sg_start_req: dxfer_len=%d\n",
1730 if (hp->cmd_len > BLK_MAX_CDB) {
1731 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1739 * With scsi-mq enabled, there are a fixed number of preallocated
1740 * requests equal in number to shost->can_queue. If all of the
1741 * preallocated requests are already in use, then blk_get_request()
1742 * will sleep until an active command completes, freeing up a request.
1743 * Although waiting in an asynchronous interface is less than ideal, we
1744 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1745 * not expect an EWOULDBLOCK from this condition.
1747 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1748 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
1755 if (hp->cmd_len > BLK_MAX_CDB)
1756 req->cmd = long_cmdp;
1757 memcpy(req->cmd, cmd, hp->cmd_len);
1758 req->cmd_len = hp->cmd_len;
1761 rq->end_io_data = srp;
1762 req->retries = SG_DEFAULT_RETRIES;
1764 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1767 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1768 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1769 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1775 mutex_lock(&sfp->f_mutex);
1776 if (dxfer_len <= rsv_schp->bufflen &&
1778 sfp->res_in_use = 1;
1779 sg_link_reserve(sfp, srp, dxfer_len);
1780 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1781 res = -EBUSY; /* sfp->res_in_use == 1 */
1782 if (dxfer_len > rsv_schp->bufflen)
1784 mutex_unlock(&sfp->f_mutex);
1787 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1789 mutex_unlock(&sfp->f_mutex);
1793 mutex_unlock(&sfp->f_mutex);
1795 md->pages = req_schp->pages;
1796 md->page_order = req_schp->page_order;
1797 md->nr_entries = req_schp->k_use_sg;
1799 md->null_mapped = hp->dxferp ? 0 : 1;
1800 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1807 struct iovec *iov = NULL;
1810 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1814 iov_iter_truncate(&i, hp->dxfer_len);
1815 if (!iov_iter_count(&i)) {
1820 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1823 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1824 hp->dxfer_len, GFP_ATOMIC);
1830 req_schp->dio_in_use = 1;
1831 hp->info |= SG_INFO_DIRECT_IO;
1838 sg_finish_rem_req(Sg_request *srp)
1842 Sg_fd *sfp = srp->parentfp;
1843 Sg_scatter_hold *req_schp = &srp->data;
1845 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1846 "sg_finish_rem_req: res_used=%d\n",
1847 (int) srp->res_used));
1849 ret = blk_rq_unmap_user(srp->bio);
1852 scsi_req_free_cmd(scsi_req(srp->rq));
1853 blk_put_request(srp->rq);
1857 sg_unlink_reserve(sfp, srp);
1859 sg_remove_scat(sfp, req_schp);
1865 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1867 int sg_bufflen = tablesize * sizeof(struct page *);
1868 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1870 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1873 schp->sglist_len = sg_bufflen;
1874 return tablesize; /* number of scat_gath elements allocated */
1878 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1880 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1881 int sg_tablesize = sfp->parentdp->sg_tablesize;
1882 int blk_size = buff_size, order;
1883 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1888 ++blk_size; /* don't know why */
1889 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1890 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1891 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1892 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1893 buff_size, blk_size));
1895 /* N.B. ret_sz carried into this block ... */
1896 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1897 if (mx_sc_elems < 0)
1898 return mx_sc_elems; /* most likely -ENOMEM */
1900 num = scatter_elem_sz;
1901 if (unlikely(num != scatter_elem_sz_prev)) {
1902 if (num < PAGE_SIZE) {
1903 scatter_elem_sz = PAGE_SIZE;
1904 scatter_elem_sz_prev = PAGE_SIZE;
1906 scatter_elem_sz_prev = num;
1909 order = get_order(num);
1911 ret_sz = 1 << (PAGE_SHIFT + order);
1913 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1914 k++, rem_sz -= ret_sz) {
1916 num = (rem_sz > scatter_elem_sz_prev) ?
1917 scatter_elem_sz_prev : rem_sz;
1919 schp->pages[k] = alloc_pages(gfp_mask, order);
1920 if (!schp->pages[k])
1923 if (num == scatter_elem_sz_prev) {
1924 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1925 scatter_elem_sz = ret_sz;
1926 scatter_elem_sz_prev = ret_sz;
1930 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1931 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1933 } /* end of for loop */
1935 schp->page_order = order;
1937 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1938 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1941 schp->bufflen = blk_size;
1942 if (rem_sz > 0) /* must have failed */
1946 for (i = 0; i < k; i++)
1947 __free_pages(schp->pages[i], order);
1956 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1958 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1959 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1960 if (schp->pages && schp->sglist_len > 0) {
1961 if (!schp->dio_in_use) {
1964 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1966 sg_printk(KERN_INFO, sfp->parentdp,
1967 "sg_remove_scat: k=%d, pg=0x%p\n",
1968 k, schp->pages[k]));
1969 __free_pages(schp->pages[k], schp->page_order);
1975 memset(schp, 0, sizeof (*schp));
1979 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1981 Sg_scatter_hold *schp = &srp->data;
1984 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1985 "sg_read_oxfer: num_read_xfer=%d\n",
1987 if ((!outp) || (num_read_xfer <= 0))
1990 num = 1 << (PAGE_SHIFT + schp->page_order);
1991 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1992 if (num > num_read_xfer) {
1993 if (copy_to_user(outp, page_address(schp->pages[k]),
1998 if (copy_to_user(outp, page_address(schp->pages[k]),
2001 num_read_xfer -= num;
2002 if (num_read_xfer <= 0)
2012 sg_build_reserve(Sg_fd * sfp, int req_size)
2014 Sg_scatter_hold *schp = &sfp->reserve;
2016 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2017 "sg_build_reserve: req_size=%d\n", req_size));
2019 if (req_size < PAGE_SIZE)
2020 req_size = PAGE_SIZE;
2021 if (0 == sg_build_indirect(schp, sfp, req_size))
2024 sg_remove_scat(sfp, schp);
2025 req_size >>= 1; /* divide by 2 */
2026 } while (req_size > (PAGE_SIZE / 2));
2030 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2032 Sg_scatter_hold *req_schp = &srp->data;
2033 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2037 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2038 "sg_link_reserve: size=%d\n", size));
2041 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2042 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2044 req_schp->k_use_sg = k + 1;
2045 req_schp->sglist_len = rsv_schp->sglist_len;
2046 req_schp->pages = rsv_schp->pages;
2048 req_schp->bufflen = size;
2049 req_schp->page_order = rsv_schp->page_order;
2055 if (k >= rsv_schp->k_use_sg)
2056 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2057 "sg_link_reserve: BAD size\n"));
2061 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2063 Sg_scatter_hold *req_schp = &srp->data;
2065 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2066 "sg_unlink_reserve: req->k_use_sg=%d\n",
2067 (int) req_schp->k_use_sg));
2068 req_schp->k_use_sg = 0;
2069 req_schp->bufflen = 0;
2070 req_schp->pages = NULL;
2071 req_schp->page_order = 0;
2072 req_schp->sglist_len = 0;
2074 /* Called without mutex lock to avoid deadlock */
2075 sfp->res_in_use = 0;
2079 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2082 unsigned long iflags;
2084 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2085 list_for_each_entry(resp, &sfp->rq_list, entry) {
2086 /* look for requests that are ready + not SG_IO owned */
2087 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2088 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2089 resp->done = 2; /* guard against other readers */
2090 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2094 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2098 /* always adds to end of list */
2100 sg_add_request(Sg_fd * sfp)
2103 unsigned long iflags;
2104 Sg_request *rp = sfp->req_arr;
2106 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2107 if (!list_empty(&sfp->rq_list)) {
2111 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2115 if (k >= SG_MAX_QUEUE)
2118 memset(rp, 0, sizeof (Sg_request));
2120 rp->header.duration = jiffies_to_msecs(jiffies);
2121 list_add_tail(&rp->entry, &sfp->rq_list);
2122 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2125 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2129 /* Return of 1 for found; 0 for not found */
2131 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2133 unsigned long iflags;
2136 if (!sfp || !srp || list_empty(&sfp->rq_list))
2138 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2139 if (!list_empty(&srp->entry)) {
2140 list_del(&srp->entry);
2141 srp->parentfp = NULL;
2144 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2149 sg_add_sfp(Sg_device * sdp)
2152 unsigned long iflags;
2155 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2157 return ERR_PTR(-ENOMEM);
2159 init_waitqueue_head(&sfp->read_wait);
2160 rwlock_init(&sfp->rq_list_lock);
2161 INIT_LIST_HEAD(&sfp->rq_list);
2162 kref_init(&sfp->f_ref);
2163 mutex_init(&sfp->f_mutex);
2164 sfp->timeout = SG_DEFAULT_TIMEOUT;
2165 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2166 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2167 sfp->cmd_q = SG_DEF_COMMAND_Q;
2168 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2169 sfp->parentdp = sdp;
2170 write_lock_irqsave(&sdp->sfd_lock, iflags);
2171 if (atomic_read(&sdp->detaching)) {
2172 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2174 return ERR_PTR(-ENODEV);
2176 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2177 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2178 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2179 "sg_add_sfp: sfp=0x%p\n", sfp));
2180 if (unlikely(sg_big_buff != def_reserved_size))
2181 sg_big_buff = def_reserved_size;
2183 bufflen = min_t(int, sg_big_buff,
2184 max_sectors_bytes(sdp->device->request_queue));
2185 sg_build_reserve(sfp, bufflen);
2186 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2187 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2188 sfp->reserve.bufflen,
2189 sfp->reserve.k_use_sg));
2191 kref_get(&sdp->d_ref);
2192 __module_get(THIS_MODULE);
2197 sg_remove_sfp_usercontext(struct work_struct *work)
2199 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2200 struct sg_device *sdp = sfp->parentdp;
2202 unsigned long iflags;
2204 /* Cleanup any responses which were never read(). */
2205 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2206 while (!list_empty(&sfp->rq_list)) {
2207 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2208 sg_finish_rem_req(srp);
2209 list_del(&srp->entry);
2210 srp->parentfp = NULL;
2212 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2214 if (sfp->reserve.bufflen > 0) {
2215 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2216 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2217 (int) sfp->reserve.bufflen,
2218 (int) sfp->reserve.k_use_sg));
2219 sg_remove_scat(sfp, &sfp->reserve);
2222 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2223 "sg_remove_sfp: sfp=0x%p\n", sfp));
2226 scsi_device_put(sdp->device);
2227 kref_put(&sdp->d_ref, sg_device_destroy);
2228 module_put(THIS_MODULE);
2232 sg_remove_sfp(struct kref *kref)
2234 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2235 struct sg_device *sdp = sfp->parentdp;
2236 unsigned long iflags;
2238 write_lock_irqsave(&sdp->sfd_lock, iflags);
2239 list_del(&sfp->sfd_siblings);
2240 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2242 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2243 schedule_work(&sfp->ew.work);
2246 #ifdef CONFIG_SCSI_PROC_FS
2248 sg_idr_max_id(int id, void *p, void *data)
2262 unsigned long iflags;
2264 read_lock_irqsave(&sg_index_lock, iflags);
2265 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2266 read_unlock_irqrestore(&sg_index_lock, iflags);
2267 return k + 1; /* origin 1 */
2271 /* must be called with sg_index_lock held */
2272 static Sg_device *sg_lookup_dev(int dev)
2274 return idr_find(&sg_index_idr, dev);
2280 struct sg_device *sdp;
2281 unsigned long flags;
2283 read_lock_irqsave(&sg_index_lock, flags);
2284 sdp = sg_lookup_dev(dev);
2286 sdp = ERR_PTR(-ENXIO);
2287 else if (atomic_read(&sdp->detaching)) {
2288 /* If sdp->detaching, then the refcount may already be 0, in
2289 * which case it would be a bug to do kref_get().
2291 sdp = ERR_PTR(-ENODEV);
2293 kref_get(&sdp->d_ref);
2294 read_unlock_irqrestore(&sg_index_lock, flags);
2299 #ifdef CONFIG_SCSI_PROC_FS
2300 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2302 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2303 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2304 size_t count, loff_t *off);
2305 static const struct proc_ops adio_proc_ops = {
2306 .proc_open = sg_proc_single_open_adio,
2307 .proc_read = seq_read,
2308 .proc_lseek = seq_lseek,
2309 .proc_write = sg_proc_write_adio,
2310 .proc_release = single_release,
2313 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2314 static ssize_t sg_proc_write_dressz(struct file *filp,
2315 const char __user *buffer, size_t count, loff_t *off);
2316 static const struct proc_ops dressz_proc_ops = {
2317 .proc_open = sg_proc_single_open_dressz,
2318 .proc_read = seq_read,
2319 .proc_lseek = seq_lseek,
2320 .proc_write = sg_proc_write_dressz,
2321 .proc_release = single_release,
2324 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2325 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2326 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2327 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2328 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2329 static void dev_seq_stop(struct seq_file *s, void *v);
2330 static const struct seq_operations dev_seq_ops = {
2331 .start = dev_seq_start,
2332 .next = dev_seq_next,
2333 .stop = dev_seq_stop,
2334 .show = sg_proc_seq_show_dev,
2337 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2338 static const struct seq_operations devstrs_seq_ops = {
2339 .start = dev_seq_start,
2340 .next = dev_seq_next,
2341 .stop = dev_seq_stop,
2342 .show = sg_proc_seq_show_devstrs,
2345 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2346 static const struct seq_operations debug_seq_ops = {
2347 .start = dev_seq_start,
2348 .next = dev_seq_next,
2349 .stop = dev_seq_stop,
2350 .show = sg_proc_seq_show_debug,
2356 struct proc_dir_entry *p;
2358 p = proc_mkdir("scsi/sg", NULL);
2362 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);
2363 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2364 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);
2365 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2366 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2367 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2368 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2373 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2375 seq_printf(s, "%d\n", *((int *)s->private));
2379 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2381 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2385 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2386 size_t count, loff_t *off)
2391 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2393 err = kstrtoul_from_user(buffer, count, 0, &num);
2396 sg_allow_dio = num ? 1 : 0;
2400 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2402 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2406 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2407 size_t count, loff_t *off)
2410 unsigned long k = ULONG_MAX;
2412 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2415 err = kstrtoul_from_user(buffer, count, 0, &k);
2418 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2425 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2427 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2432 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2434 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2438 struct sg_proc_deviter {
2443 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2445 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2452 it->max = sg_last_dev();
2453 if (it->index >= it->max)
2458 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2460 struct sg_proc_deviter * it = s->private;
2463 return (it->index < it->max) ? it : NULL;
2466 static void dev_seq_stop(struct seq_file *s, void *v)
2471 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2473 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2475 struct scsi_device *scsidp;
2476 unsigned long iflags;
2478 read_lock_irqsave(&sg_index_lock, iflags);
2479 sdp = it ? sg_lookup_dev(it->index) : NULL;
2480 if ((NULL == sdp) || (NULL == sdp->device) ||
2481 (atomic_read(&sdp->detaching)))
2482 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2484 scsidp = sdp->device;
2485 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2486 scsidp->host->host_no, scsidp->channel,
2487 scsidp->id, scsidp->lun, (int) scsidp->type,
2489 (int) scsidp->queue_depth,
2490 (int) scsi_device_busy(scsidp),
2491 (int) scsi_device_online(scsidp));
2493 read_unlock_irqrestore(&sg_index_lock, iflags);
2497 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2499 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2501 struct scsi_device *scsidp;
2502 unsigned long iflags;
2504 read_lock_irqsave(&sg_index_lock, iflags);
2505 sdp = it ? sg_lookup_dev(it->index) : NULL;
2506 scsidp = sdp ? sdp->device : NULL;
2507 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2508 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2509 scsidp->vendor, scsidp->model, scsidp->rev);
2511 seq_puts(s, "<no active device>\n");
2512 read_unlock_irqrestore(&sg_index_lock, iflags);
2516 /* must be called while holding sg_index_lock */
2517 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2519 int k, new_interface, blen, usg;
2522 const sg_io_hdr_t *hp;
2527 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2529 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2530 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2531 "(res)sgat=%d low_dma=%d\n", k,
2532 jiffies_to_msecs(fp->timeout),
2533 fp->reserve.bufflen,
2534 (int) fp->reserve.k_use_sg, 0);
2535 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2536 (int) fp->cmd_q, (int) fp->force_packid,
2537 (int) fp->keep_orphan);
2538 list_for_each_entry(srp, &fp->rq_list, entry) {
2540 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2541 if (srp->res_used) {
2542 if (new_interface &&
2543 (SG_FLAG_MMAP_IO & hp->flags))
2548 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2554 blen = srp->data.bufflen;
2555 usg = srp->data.k_use_sg;
2556 seq_puts(s, srp->done ?
2557 ((1 == srp->done) ? "rcv:" : "fin:")
2559 seq_printf(s, " id=%d blen=%d",
2560 srp->header.pack_id, blen);
2562 seq_printf(s, " dur=%d", hp->duration);
2564 ms = jiffies_to_msecs(jiffies);
2565 seq_printf(s, " t_o/elap=%d/%d",
2566 (new_interface ? hp->timeout :
2567 jiffies_to_msecs(fp->timeout)),
2568 (ms > hp->duration ? ms - hp->duration : 0));
2570 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2571 (int) srp->data.cmd_opcode);
2573 if (list_empty(&fp->rq_list))
2574 seq_puts(s, " No requests active\n");
2575 read_unlock(&fp->rq_list_lock);
2579 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2581 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2583 unsigned long iflags;
2585 if (it && (0 == it->index))
2586 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2587 (int)it->max, sg_big_buff);
2589 read_lock_irqsave(&sg_index_lock, iflags);
2590 sdp = it ? sg_lookup_dev(it->index) : NULL;
2593 read_lock(&sdp->sfd_lock);
2594 if (!list_empty(&sdp->sfds)) {
2595 seq_printf(s, " >>> device=%s ", sdp->name);
2596 if (atomic_read(&sdp->detaching))
2597 seq_puts(s, "detaching pending close ");
2598 else if (sdp->device) {
2599 struct scsi_device *scsidp = sdp->device;
2601 seq_printf(s, "%d:%d:%d:%llu em=%d",
2602 scsidp->host->host_no,
2603 scsidp->channel, scsidp->id,
2605 scsidp->host->hostt->emulated);
2607 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2608 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2609 sg_proc_debug_helper(s, sdp);
2611 read_unlock(&sdp->sfd_lock);
2613 read_unlock_irqrestore(&sg_index_lock, iflags);
2617 #endif /* CONFIG_SCSI_PROC_FS */
2619 module_init(init_sg);
2620 module_exit(exit_sg);