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 struct gendisk *disk;
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, \
206 (sdp)->disk->disk_name, fmt, ##a)
209 * The SCSI interfaces that use read() and write() as an asynchronous variant of
210 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
211 * to trigger read() and write() calls from various contexts with elevated
212 * privileges. This can lead to kernel memory corruption (e.g. if these
213 * interfaces are called through splice()) and privilege escalation inside
214 * userspace (e.g. if a process with access to such a device passes a file
215 * descriptor to a SUID binary as stdin/stdout/stderr).
217 * This function provides protection for the legacy API by restricting the
220 static int sg_check_file_access(struct file *filp, const char *caller)
222 if (filp->f_cred != current_real_cred()) {
223 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
224 caller, task_tgid_vnr(current), current->comm);
227 if (uaccess_kernel()) {
228 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
229 caller, task_tgid_vnr(current), current->comm);
235 static int sg_allow_access(struct file *filp, unsigned char *cmd)
237 struct sg_fd *sfp = filp->private_data;
239 if (sfp->parentdp->device->type == TYPE_SCANNER)
242 return blk_verify_command(cmd, filp->f_mode);
246 open_wait(Sg_device *sdp, int flags)
250 if (flags & O_EXCL) {
251 while (sdp->open_cnt > 0) {
252 mutex_unlock(&sdp->open_rel_lock);
253 retval = wait_event_interruptible(sdp->open_wait,
254 (atomic_read(&sdp->detaching) ||
256 mutex_lock(&sdp->open_rel_lock);
258 if (retval) /* -ERESTARTSYS */
260 if (atomic_read(&sdp->detaching))
264 while (sdp->exclude) {
265 mutex_unlock(&sdp->open_rel_lock);
266 retval = wait_event_interruptible(sdp->open_wait,
267 (atomic_read(&sdp->detaching) ||
269 mutex_lock(&sdp->open_rel_lock);
271 if (retval) /* -ERESTARTSYS */
273 if (atomic_read(&sdp->detaching))
281 /* Returns 0 on success, else a negated errno value */
283 sg_open(struct inode *inode, struct file *filp)
285 int dev = iminor(inode);
286 int flags = filp->f_flags;
287 struct request_queue *q;
292 nonseekable_open(inode, filp);
293 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
294 return -EPERM; /* Can't lock it with read only access */
295 sdp = sg_get_dev(dev);
299 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
300 "sg_open: flags=0x%x\n", flags));
302 /* This driver's module count bumped by fops_get in <linux/fs.h> */
303 /* Prevent the device driver from vanishing while we sleep */
304 retval = scsi_device_get(sdp->device);
308 retval = scsi_autopm_get_device(sdp->device);
312 /* scsi_block_when_processing_errors() may block so bypass
313 * check if O_NONBLOCK. Permits SCSI commands to be issued
314 * during error recovery. Tread carefully. */
315 if (!((flags & O_NONBLOCK) ||
316 scsi_block_when_processing_errors(sdp->device))) {
318 /* we are in error recovery for this device */
322 mutex_lock(&sdp->open_rel_lock);
323 if (flags & O_NONBLOCK) {
324 if (flags & O_EXCL) {
325 if (sdp->open_cnt > 0) {
327 goto error_mutex_locked;
332 goto error_mutex_locked;
336 retval = open_wait(sdp, flags);
337 if (retval) /* -ERESTARTSYS or -ENODEV */
338 goto error_mutex_locked;
341 /* N.B. at this point we are holding the open_rel_lock */
345 if (sdp->open_cnt < 1) { /* no existing opens */
347 q = sdp->device->request_queue;
348 sdp->sg_tablesize = queue_max_segments(q);
350 sfp = sg_add_sfp(sdp);
352 retval = PTR_ERR(sfp);
356 filp->private_data = sfp;
358 mutex_unlock(&sdp->open_rel_lock);
362 kref_put(&sdp->d_ref, sg_device_destroy);
366 if (flags & O_EXCL) {
367 sdp->exclude = false; /* undo if error */
368 wake_up_interruptible(&sdp->open_wait);
371 mutex_unlock(&sdp->open_rel_lock);
373 scsi_autopm_put_device(sdp->device);
375 scsi_device_put(sdp->device);
379 /* Release resources associated with a successful sg_open()
380 * Returns 0 on success, else a negated errno value */
382 sg_release(struct inode *inode, struct file *filp)
387 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
389 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
391 mutex_lock(&sdp->open_rel_lock);
392 scsi_autopm_put_device(sdp->device);
393 kref_put(&sfp->f_ref, sg_remove_sfp);
396 /* possibly many open()s waiting on exlude clearing, start many;
397 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
399 sdp->exclude = false;
400 wake_up_interruptible_all(&sdp->open_wait);
401 } else if (0 == sdp->open_cnt) {
402 wake_up_interruptible(&sdp->open_wait);
404 mutex_unlock(&sdp->open_rel_lock);
409 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
414 int req_pack_id = -1;
416 struct sg_header *old_hdr = NULL;
420 * This could cause a response to be stranded. Close the associated
421 * file descriptor to free up any resources being held.
423 retval = sg_check_file_access(filp, __func__);
427 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
429 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
430 "sg_read: count=%d\n", (int) count));
432 if (!access_ok(buf, count))
434 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
435 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
438 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
442 if (old_hdr->reply_len < 0) {
443 if (count >= SZ_SG_IO_HDR) {
444 sg_io_hdr_t *new_hdr;
445 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
450 retval =__copy_from_user
451 (new_hdr, buf, SZ_SG_IO_HDR);
452 req_pack_id = new_hdr->pack_id;
460 req_pack_id = old_hdr->pack_id;
462 srp = sg_get_rq_mark(sfp, req_pack_id);
463 if (!srp) { /* now wait on packet to arrive */
464 if (atomic_read(&sdp->detaching)) {
468 if (filp->f_flags & O_NONBLOCK) {
472 retval = wait_event_interruptible(sfp->read_wait,
473 (atomic_read(&sdp->detaching) ||
474 (srp = sg_get_rq_mark(sfp, req_pack_id))));
475 if (atomic_read(&sdp->detaching)) {
480 /* -ERESTARTSYS as signal hit process */
484 if (srp->header.interface_id != '\0') {
485 retval = sg_new_read(sfp, buf, count, srp);
490 if (old_hdr == NULL) {
491 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
497 memset(old_hdr, 0, SZ_SG_HEADER);
498 old_hdr->reply_len = (int) hp->timeout;
499 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
500 old_hdr->pack_id = hp->pack_id;
501 old_hdr->twelve_byte =
502 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
503 old_hdr->target_status = hp->masked_status;
504 old_hdr->host_status = hp->host_status;
505 old_hdr->driver_status = hp->driver_status;
506 if ((CHECK_CONDITION & hp->masked_status) ||
507 (DRIVER_SENSE & hp->driver_status))
508 memcpy(old_hdr->sense_buffer, srp->sense_b,
509 sizeof (old_hdr->sense_buffer));
510 switch (hp->host_status) {
511 /* This setup of 'result' is for backward compatibility and is best
512 ignored by the user who should use target, host + driver status */
514 case DID_PASSTHROUGH:
521 old_hdr->result = EBUSY;
528 old_hdr->result = EIO;
531 old_hdr->result = (srp->sense_b[0] == 0 &&
532 hp->masked_status == GOOD) ? 0 : EIO;
535 old_hdr->result = EIO;
539 /* Now copy the result back to the user buffer. */
540 if (count >= SZ_SG_HEADER) {
541 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
546 if (count > old_hdr->reply_len)
547 count = old_hdr->reply_len;
548 if (count > SZ_SG_HEADER) {
549 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
555 count = (old_hdr->result == 0) ? 0 : -EIO;
556 sg_finish_rem_req(srp);
557 sg_remove_request(sfp, srp);
565 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
567 sg_io_hdr_t *hp = &srp->header;
571 if (count < SZ_SG_IO_HDR) {
576 if ((hp->mx_sb_len > 0) && hp->sbp) {
577 if ((CHECK_CONDITION & hp->masked_status) ||
578 (DRIVER_SENSE & hp->driver_status)) {
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)) {
590 if (hp->masked_status || hp->host_status || hp->driver_status)
591 hp->info |= SG_INFO_CHECK;
592 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
597 err2 = sg_finish_rem_req(srp);
598 sg_remove_request(sfp, srp);
599 return err ? : err2 ? : count;
603 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
605 int mxsize, cmd_size, k;
606 int input_size, blocking;
607 unsigned char opcode;
611 struct sg_header old_hdr;
613 unsigned char cmnd[SG_MAX_CDB_SIZE];
616 retval = sg_check_file_access(filp, __func__);
620 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
622 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
623 "sg_write: count=%d\n", (int) count));
624 if (atomic_read(&sdp->detaching))
626 if (!((filp->f_flags & O_NONBLOCK) ||
627 scsi_block_when_processing_errors(sdp->device)))
630 if (!access_ok(buf, count))
631 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
632 if (count < SZ_SG_HEADER)
634 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
636 blocking = !(filp->f_flags & O_NONBLOCK);
637 if (old_hdr.reply_len < 0)
638 return sg_new_write(sfp, filp, buf, count,
639 blocking, 0, 0, NULL);
640 if (count < (SZ_SG_HEADER + 6))
641 return -EIO; /* The minimum scsi command length is 6 bytes. */
643 if (!(srp = sg_add_request(sfp))) {
644 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
645 "sg_write: queue full\n"));
649 __get_user(opcode, buf);
650 mutex_lock(&sfp->f_mutex);
651 if (sfp->next_cmd_len > 0) {
652 cmd_size = sfp->next_cmd_len;
653 sfp->next_cmd_len = 0; /* reset so only this write() effected */
655 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
656 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
659 mutex_unlock(&sfp->f_mutex);
660 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
661 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
662 /* Determine buffer size. */
663 input_size = count - cmd_size;
664 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
665 mxsize -= SZ_SG_HEADER;
666 input_size -= SZ_SG_HEADER;
667 if (input_size < 0) {
668 sg_remove_request(sfp, srp);
669 return -EIO; /* User did not pass enough bytes for this command. */
672 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
673 hp->cmd_len = (unsigned char) cmd_size;
677 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
678 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
680 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
681 hp->dxfer_len = mxsize;
682 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
683 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
684 hp->dxferp = (char __user *)buf + cmd_size;
688 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
689 hp->flags = input_size; /* structure abuse ... */
690 hp->pack_id = old_hdr.pack_id;
692 if (__copy_from_user(cmnd, buf, cmd_size)) {
693 sg_remove_request(sfp, srp);
697 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
698 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
699 * is a non-zero input_size, so emit a warning.
701 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
702 printk_ratelimited(KERN_WARNING
703 "sg_write: data in/out %d/%d bytes "
704 "for SCSI command 0x%x-- guessing "
705 "data in;\n program %s not setting "
706 "count and/or reply_len properly\n",
707 old_hdr.reply_len - (int)SZ_SG_HEADER,
708 input_size, (unsigned int) cmnd[0],
711 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
712 return (k < 0) ? k : count;
716 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
717 size_t count, int blocking, int read_only, int sg_io_owned,
723 unsigned char cmnd[SG_MAX_CDB_SIZE];
725 unsigned long ul_timeout;
727 if (count < SZ_SG_IO_HDR)
729 if (!access_ok(buf, count))
730 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
732 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
733 if (!(srp = sg_add_request(sfp))) {
734 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
735 "sg_new_write: queue full\n"));
738 srp->sg_io_owned = sg_io_owned;
740 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
741 sg_remove_request(sfp, srp);
744 if (hp->interface_id != 'S') {
745 sg_remove_request(sfp, srp);
748 if (hp->flags & SG_FLAG_MMAP_IO) {
749 if (hp->dxfer_len > sfp->reserve.bufflen) {
750 sg_remove_request(sfp, srp);
751 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
753 if (hp->flags & SG_FLAG_DIRECT_IO) {
754 sg_remove_request(sfp, srp);
755 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
757 if (sfp->res_in_use) {
758 sg_remove_request(sfp, srp);
759 return -EBUSY; /* reserve buffer already being used */
762 ul_timeout = msecs_to_jiffies(srp->header.timeout);
763 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
764 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
765 sg_remove_request(sfp, srp);
768 if (!access_ok(hp->cmdp, hp->cmd_len)) {
769 sg_remove_request(sfp, srp);
770 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
772 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
773 sg_remove_request(sfp, srp);
776 if (read_only && sg_allow_access(file, cmnd)) {
777 sg_remove_request(sfp, srp);
780 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
789 sg_common_write(Sg_fd * sfp, Sg_request * srp,
790 unsigned char *cmnd, int timeout, int blocking)
793 Sg_device *sdp = sfp->parentdp;
794 sg_io_hdr_t *hp = &srp->header;
796 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
798 hp->masked_status = 0;
802 hp->driver_status = 0;
804 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
805 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
806 (int) cmnd[0], (int) hp->cmd_len));
808 if (hp->dxfer_len >= SZ_256M) {
809 sg_remove_request(sfp, srp);
813 k = sg_start_req(srp, cmnd);
815 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
816 "sg_common_write: start_req err=%d\n", k));
817 sg_finish_rem_req(srp);
818 sg_remove_request(sfp, srp);
819 return k; /* probably out of space --> ENOMEM */
821 if (atomic_read(&sdp->detaching)) {
823 scsi_req_free_cmd(scsi_req(srp->rq));
824 blk_put_request(srp->rq);
828 sg_finish_rem_req(srp);
829 sg_remove_request(sfp, srp);
833 hp->duration = jiffies_to_msecs(jiffies);
834 if (hp->interface_id != '\0' && /* v3 (or later) interface */
835 (SG_FLAG_Q_AT_TAIL & hp->flags))
840 srp->rq->timeout = timeout;
841 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
842 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
843 srp->rq, at_head, sg_rq_end_io);
847 static int srp_done(Sg_fd *sfp, Sg_request *srp)
852 read_lock_irqsave(&sfp->rq_list_lock, flags);
854 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
858 static int max_sectors_bytes(struct request_queue *q)
860 unsigned int max_sectors = queue_max_sectors(q);
862 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
864 return max_sectors << 9;
868 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
875 list_for_each_entry(srp, &sfp->rq_list, entry) {
876 if (val >= SG_MAX_QUEUE)
878 rinfo[val].req_state = srp->done + 1;
880 srp->header.masked_status &
881 srp->header.host_status &
882 srp->header.driver_status;
884 rinfo[val].duration =
885 srp->header.duration;
887 ms = jiffies_to_msecs(jiffies);
888 rinfo[val].duration =
889 (ms > srp->header.duration) ?
890 (ms - srp->header.duration) : 0;
892 rinfo[val].orphan = srp->orphan;
893 rinfo[val].sg_io_owned = srp->sg_io_owned;
894 rinfo[val].pack_id = srp->header.pack_id;
895 rinfo[val].usr_ptr = srp->header.usr_ptr;
901 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
903 void __user *p = (void __user *)arg;
905 int result, val, read_only;
909 unsigned long iflags;
911 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
914 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
915 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
916 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
920 if (atomic_read(&sdp->detaching))
922 if (!scsi_block_when_processing_errors(sdp->device))
924 if (!access_ok(p, SZ_SG_IO_HDR))
926 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
927 1, read_only, 1, &srp);
930 result = wait_event_interruptible(sfp->read_wait,
931 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
932 if (atomic_read(&sdp->detaching))
934 write_lock_irq(&sfp->rq_list_lock);
937 write_unlock_irq(&sfp->rq_list_lock);
938 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
939 return (result < 0) ? result : 0;
942 write_unlock_irq(&sfp->rq_list_lock);
943 return result; /* -ERESTARTSYS because signal hit process */
945 result = get_user(val, ip);
950 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
951 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
953 sfp->timeout_user = val;
954 sfp->timeout = mult_frac(val, HZ, USER_HZ);
957 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
958 /* strange ..., for backward compatibility */
959 return sfp->timeout_user;
960 case SG_SET_FORCE_LOW_DMA:
962 * N.B. This ioctl never worked properly, but failed to
963 * return an error value. So returning '0' to keep compability
964 * with legacy applications.
968 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
970 if (!access_ok(p, sizeof (sg_scsi_id_t)))
973 sg_scsi_id_t __user *sg_idp = p;
975 if (atomic_read(&sdp->detaching))
977 __put_user((int) sdp->device->host->host_no,
979 __put_user((int) sdp->device->channel,
981 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
982 __put_user((int) sdp->device->lun, &sg_idp->lun);
983 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
984 __put_user((short) sdp->device->host->cmd_per_lun,
985 &sg_idp->h_cmd_per_lun);
986 __put_user((short) sdp->device->queue_depth,
987 &sg_idp->d_queue_depth);
988 __put_user(0, &sg_idp->unused[0]);
989 __put_user(0, &sg_idp->unused[1]);
992 case SG_SET_FORCE_PACK_ID:
993 result = get_user(val, ip);
996 sfp->force_packid = val ? 1 : 0;
999 if (!access_ok(ip, sizeof (int)))
1001 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1002 list_for_each_entry(srp, &sfp->rq_list, entry) {
1003 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1004 read_unlock_irqrestore(&sfp->rq_list_lock,
1006 __put_user(srp->header.pack_id, ip);
1010 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1013 case SG_GET_NUM_WAITING:
1014 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1016 list_for_each_entry(srp, &sfp->rq_list, entry) {
1017 if ((1 == srp->done) && (!srp->sg_io_owned))
1020 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1021 return put_user(val, ip);
1022 case SG_GET_SG_TABLESIZE:
1023 return put_user(sdp->sg_tablesize, ip);
1024 case SG_SET_RESERVED_SIZE:
1025 result = get_user(val, ip);
1030 val = min_t(int, val,
1031 max_sectors_bytes(sdp->device->request_queue));
1032 mutex_lock(&sfp->f_mutex);
1033 if (val != sfp->reserve.bufflen) {
1034 if (sfp->mmap_called ||
1036 mutex_unlock(&sfp->f_mutex);
1040 sg_remove_scat(sfp, &sfp->reserve);
1041 sg_build_reserve(sfp, val);
1043 mutex_unlock(&sfp->f_mutex);
1045 case SG_GET_RESERVED_SIZE:
1046 val = min_t(int, sfp->reserve.bufflen,
1047 max_sectors_bytes(sdp->device->request_queue));
1048 return put_user(val, ip);
1049 case SG_SET_COMMAND_Q:
1050 result = get_user(val, ip);
1053 sfp->cmd_q = val ? 1 : 0;
1055 case SG_GET_COMMAND_Q:
1056 return put_user((int) sfp->cmd_q, ip);
1057 case SG_SET_KEEP_ORPHAN:
1058 result = get_user(val, ip);
1061 sfp->keep_orphan = val;
1063 case SG_GET_KEEP_ORPHAN:
1064 return put_user((int) sfp->keep_orphan, ip);
1065 case SG_NEXT_CMD_LEN:
1066 result = get_user(val, ip);
1069 if (val > SG_MAX_CDB_SIZE)
1071 sfp->next_cmd_len = (val > 0) ? val : 0;
1073 case SG_GET_VERSION_NUM:
1074 return put_user(sg_version_num, ip);
1075 case SG_GET_ACCESS_COUNT:
1076 /* faked - we don't have a real access count anymore */
1077 val = (sdp->device ? 1 : 0);
1078 return put_user(val, ip);
1079 case SG_GET_REQUEST_TABLE:
1080 if (!access_ok(p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
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 result = __copy_to_user(p, rinfo,
1093 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1094 result = result ? -EFAULT : 0;
1098 case SG_EMULATED_HOST:
1099 if (atomic_read(&sdp->detaching))
1101 return put_user(sdp->device->host->hostt->emulated, ip);
1102 case SCSI_IOCTL_SEND_COMMAND:
1103 if (atomic_read(&sdp->detaching))
1105 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1107 result = get_user(val, ip);
1110 sdp->sgdebug = (char) val;
1113 return put_user(max_sectors_bytes(sdp->device->request_queue),
1116 return blk_trace_setup(sdp->device->request_queue,
1117 sdp->disk->disk_name,
1118 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1121 return blk_trace_startstop(sdp->device->request_queue, 1);
1123 return blk_trace_startstop(sdp->device->request_queue, 0);
1124 case BLKTRACETEARDOWN:
1125 return blk_trace_remove(sdp->device->request_queue);
1126 case SCSI_IOCTL_GET_IDLUN:
1127 case SCSI_IOCTL_GET_BUS_NUMBER:
1128 case SCSI_IOCTL_PROBE_HOST:
1129 case SG_GET_TRANSFORM:
1131 if (atomic_read(&sdp->detaching))
1136 return -EPERM; /* don't know so take safe approach */
1140 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1141 cmd_in, filp->f_flags & O_NDELAY);
1144 return scsi_ioctl(sdp->device, cmd_in, p);
1147 #ifdef CONFIG_COMPAT
1148 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1152 struct scsi_device *sdev;
1154 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1158 if (sdev->host->hostt->compat_ioctl) {
1161 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1166 return -ENOIOCTLCMD;
1171 sg_poll(struct file *filp, poll_table * wait)
1178 unsigned long iflags;
1180 sfp = filp->private_data;
1183 sdp = sfp->parentdp;
1186 poll_wait(filp, &sfp->read_wait, wait);
1187 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1188 list_for_each_entry(srp, &sfp->rq_list, entry) {
1189 /* if any read waiting, flag it */
1190 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1191 res = EPOLLIN | EPOLLRDNORM;
1194 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1196 if (atomic_read(&sdp->detaching))
1198 else if (!sfp->cmd_q) {
1200 res |= EPOLLOUT | EPOLLWRNORM;
1201 } else if (count < SG_MAX_QUEUE)
1202 res |= EPOLLOUT | EPOLLWRNORM;
1203 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1204 "sg_poll: res=0x%x\n", (__force u32) res));
1209 sg_fasync(int fd, struct file *filp, int mode)
1214 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1216 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1217 "sg_fasync: mode=%d\n", mode));
1219 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1223 sg_vma_fault(struct vm_fault *vmf)
1225 struct vm_area_struct *vma = vmf->vma;
1227 unsigned long offset, len, sa;
1228 Sg_scatter_hold *rsv_schp;
1231 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1232 return VM_FAULT_SIGBUS;
1233 rsv_schp = &sfp->reserve;
1234 offset = vmf->pgoff << PAGE_SHIFT;
1235 if (offset >= rsv_schp->bufflen)
1236 return VM_FAULT_SIGBUS;
1237 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1238 "sg_vma_fault: offset=%lu, scatg=%d\n",
1239 offset, rsv_schp->k_use_sg));
1241 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1242 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1243 len = vma->vm_end - sa;
1244 len = (len < length) ? len : length;
1246 struct page *page = nth_page(rsv_schp->pages[k],
1247 offset >> PAGE_SHIFT);
1248 get_page(page); /* increment page count */
1250 return 0; /* success */
1256 return VM_FAULT_SIGBUS;
1259 static const struct vm_operations_struct sg_mmap_vm_ops = {
1260 .fault = sg_vma_fault,
1264 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1267 unsigned long req_sz, len, sa;
1268 Sg_scatter_hold *rsv_schp;
1272 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1274 req_sz = vma->vm_end - vma->vm_start;
1275 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1276 "sg_mmap starting, vm_start=%p, len=%d\n",
1277 (void *) vma->vm_start, (int) req_sz));
1279 return -EINVAL; /* want no offset */
1280 rsv_schp = &sfp->reserve;
1281 mutex_lock(&sfp->f_mutex);
1282 if (req_sz > rsv_schp->bufflen) {
1283 ret = -ENOMEM; /* cannot map more than reserved buffer */
1288 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1289 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1290 len = vma->vm_end - sa;
1291 len = (len < length) ? len : length;
1295 sfp->mmap_called = 1;
1296 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1297 vma->vm_private_data = sfp;
1298 vma->vm_ops = &sg_mmap_vm_ops;
1300 mutex_unlock(&sfp->f_mutex);
1305 sg_rq_end_io_usercontext(struct work_struct *work)
1307 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1308 struct sg_fd *sfp = srp->parentfp;
1310 sg_finish_rem_req(srp);
1311 sg_remove_request(sfp, srp);
1312 kref_put(&sfp->f_ref, sg_remove_sfp);
1316 * This function is a "bottom half" handler that is called by the mid
1317 * level when a command is completed (or has failed).
1320 sg_rq_end_io(struct request *rq, blk_status_t status)
1322 struct sg_request *srp = rq->end_io_data;
1323 struct scsi_request *req = scsi_req(rq);
1326 unsigned long iflags;
1329 int result, resid, done = 1;
1331 if (WARN_ON(srp->done != 0))
1334 sfp = srp->parentfp;
1335 if (WARN_ON(sfp == NULL))
1338 sdp = sfp->parentdp;
1339 if (unlikely(atomic_read(&sdp->detaching)))
1340 pr_info("%s: device detaching\n", __func__);
1343 result = req->result;
1344 resid = req->resid_len;
1346 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1347 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1348 srp->header.pack_id, result));
1349 srp->header.resid = resid;
1350 ms = jiffies_to_msecs(jiffies);
1351 srp->header.duration = (ms > srp->header.duration) ?
1352 (ms - srp->header.duration) : 0;
1354 struct scsi_sense_hdr sshdr;
1356 srp->header.status = 0xff & result;
1357 srp->header.masked_status = status_byte(result);
1358 srp->header.msg_status = msg_byte(result);
1359 srp->header.host_status = host_byte(result);
1360 srp->header.driver_status = driver_byte(result);
1361 if ((sdp->sgdebug > 0) &&
1362 ((CHECK_CONDITION == srp->header.masked_status) ||
1363 (COMMAND_TERMINATED == srp->header.masked_status)))
1364 __scsi_print_sense(sdp->device, __func__, sense,
1365 SCSI_SENSE_BUFFERSIZE);
1367 /* Following if statement is a patch supplied by Eric Youngdale */
1368 if (driver_byte(result) != 0
1369 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1370 && !scsi_sense_is_deferred(&sshdr)
1371 && sshdr.sense_key == UNIT_ATTENTION
1372 && sdp->device->removable) {
1373 /* Detected possible disc change. Set the bit - this */
1374 /* may be used if there are filesystems using this device */
1375 sdp->device->changed = 1;
1380 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1382 /* Rely on write phase to clean out srp status values, so no "else" */
1385 * Free the request as soon as it is complete so that its resources
1386 * can be reused without waiting for userspace to read() the
1387 * result. But keep the associated bio (if any) around until
1388 * blk_rq_unmap_user() can be called from user context.
1391 scsi_req_free_cmd(scsi_req(rq));
1392 blk_put_request(rq);
1394 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1395 if (unlikely(srp->orphan)) {
1396 if (sfp->keep_orphan)
1397 srp->sg_io_owned = 0;
1402 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1405 /* Now wake up any sg_read() that is waiting for this
1408 wake_up_interruptible(&sfp->read_wait);
1409 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1410 kref_put(&sfp->f_ref, sg_remove_sfp);
1412 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1413 schedule_work(&srp->ew.work);
1417 static const struct file_operations sg_fops = {
1418 .owner = THIS_MODULE,
1422 .unlocked_ioctl = sg_ioctl,
1423 #ifdef CONFIG_COMPAT
1424 .compat_ioctl = sg_compat_ioctl,
1428 .release = sg_release,
1429 .fasync = sg_fasync,
1430 .llseek = no_llseek,
1433 static struct class *sg_sysfs_class;
1435 static int sg_sysfs_valid = 0;
1438 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1440 struct request_queue *q = scsidp->request_queue;
1442 unsigned long iflags;
1446 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1448 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1449 "failure\n", __func__);
1450 return ERR_PTR(-ENOMEM);
1453 idr_preload(GFP_KERNEL);
1454 write_lock_irqsave(&sg_index_lock, iflags);
1456 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1458 if (error == -ENOSPC) {
1459 sdev_printk(KERN_WARNING, scsidp,
1460 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1461 scsidp->type, SG_MAX_DEVS - 1);
1464 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1465 "allocation Sg_device failure: %d\n",
1472 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1473 "sg_alloc: dev=%d \n", k));
1474 sprintf(disk->disk_name, "sg%d", k);
1475 disk->first_minor = k;
1477 sdp->device = scsidp;
1478 mutex_init(&sdp->open_rel_lock);
1479 INIT_LIST_HEAD(&sdp->sfds);
1480 init_waitqueue_head(&sdp->open_wait);
1481 atomic_set(&sdp->detaching, 0);
1482 rwlock_init(&sdp->sfd_lock);
1483 sdp->sg_tablesize = queue_max_segments(q);
1485 kref_init(&sdp->d_ref);
1489 write_unlock_irqrestore(&sg_index_lock, iflags);
1494 return ERR_PTR(error);
1500 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1502 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1503 struct gendisk *disk;
1504 Sg_device *sdp = NULL;
1505 struct cdev * cdev = NULL;
1507 unsigned long iflags;
1509 disk = alloc_disk(1);
1511 pr_warn("%s: alloc_disk failed\n", __func__);
1514 disk->major = SCSI_GENERIC_MAJOR;
1517 cdev = cdev_alloc();
1519 pr_warn("%s: cdev_alloc failed\n", __func__);
1522 cdev->owner = THIS_MODULE;
1523 cdev->ops = &sg_fops;
1525 sdp = sg_alloc(disk, scsidp);
1527 pr_warn("%s: sg_alloc failed\n", __func__);
1528 error = PTR_ERR(sdp);
1532 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1537 if (sg_sysfs_valid) {
1538 struct device *sg_class_member;
1540 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1541 MKDEV(SCSI_GENERIC_MAJOR,
1543 sdp, "%s", disk->disk_name);
1544 if (IS_ERR(sg_class_member)) {
1545 pr_err("%s: device_create failed\n", __func__);
1546 error = PTR_ERR(sg_class_member);
1549 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1550 &sg_class_member->kobj, "generic");
1552 pr_err("%s: unable to make symlink 'generic' back "
1553 "to sg%d\n", __func__, sdp->index);
1555 pr_warn("%s: sg_sys Invalid\n", __func__);
1557 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1558 "type %d\n", sdp->index, scsidp->type);
1560 dev_set_drvdata(cl_dev, sdp);
1565 write_lock_irqsave(&sg_index_lock, iflags);
1566 idr_remove(&sg_index_idr, sdp->index);
1567 write_unlock_irqrestore(&sg_index_lock, iflags);
1578 sg_device_destroy(struct kref *kref)
1580 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1581 unsigned long flags;
1583 /* CAUTION! Note that the device can still be found via idr_find()
1584 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1585 * any other cleanup.
1588 write_lock_irqsave(&sg_index_lock, flags);
1589 idr_remove(&sg_index_idr, sdp->index);
1590 write_unlock_irqrestore(&sg_index_lock, flags);
1593 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1595 put_disk(sdp->disk);
1600 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1602 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1603 Sg_device *sdp = dev_get_drvdata(cl_dev);
1604 unsigned long iflags;
1610 /* want sdp->detaching non-zero as soon as possible */
1611 val = atomic_inc_return(&sdp->detaching);
1613 return; /* only want to do following once per device */
1615 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1618 read_lock_irqsave(&sdp->sfd_lock, iflags);
1619 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1620 wake_up_interruptible_all(&sfp->read_wait);
1621 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1623 wake_up_interruptible_all(&sdp->open_wait);
1624 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1626 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1627 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1628 cdev_del(sdp->cdev);
1631 kref_put(&sdp->d_ref, sg_device_destroy);
1634 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1635 module_param_named(def_reserved_size, def_reserved_size, int,
1637 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1639 MODULE_AUTHOR("Douglas Gilbert");
1640 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1641 MODULE_LICENSE("GPL");
1642 MODULE_VERSION(SG_VERSION_STR);
1643 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1645 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1646 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1647 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1648 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1655 if (scatter_elem_sz < PAGE_SIZE) {
1656 scatter_elem_sz = PAGE_SIZE;
1657 scatter_elem_sz_prev = scatter_elem_sz;
1659 if (def_reserved_size >= 0)
1660 sg_big_buff = def_reserved_size;
1662 def_reserved_size = sg_big_buff;
1664 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1668 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1669 if ( IS_ERR(sg_sysfs_class) ) {
1670 rc = PTR_ERR(sg_sysfs_class);
1674 rc = scsi_register_interface(&sg_interface);
1676 #ifdef CONFIG_SCSI_PROC_FS
1678 #endif /* CONFIG_SCSI_PROC_FS */
1681 class_destroy(sg_sysfs_class);
1683 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1690 #ifdef CONFIG_SCSI_PROC_FS
1691 remove_proc_subtree("scsi/sg", NULL);
1692 #endif /* CONFIG_SCSI_PROC_FS */
1693 scsi_unregister_interface(&sg_interface);
1694 class_destroy(sg_sysfs_class);
1696 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1698 idr_destroy(&sg_index_idr);
1702 sg_start_req(Sg_request *srp, unsigned char *cmd)
1706 struct scsi_request *req;
1707 Sg_fd *sfp = srp->parentfp;
1708 sg_io_hdr_t *hp = &srp->header;
1709 int dxfer_len = (int) hp->dxfer_len;
1710 int dxfer_dir = hp->dxfer_direction;
1711 unsigned int iov_count = hp->iovec_count;
1712 Sg_scatter_hold *req_schp = &srp->data;
1713 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1714 struct request_queue *q = sfp->parentdp->device->request_queue;
1715 struct rq_map_data *md, map_data;
1716 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1717 unsigned char *long_cmdp = NULL;
1719 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1720 "sg_start_req: dxfer_len=%d\n",
1723 if (hp->cmd_len > BLK_MAX_CDB) {
1724 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1732 * With scsi-mq enabled, there are a fixed number of preallocated
1733 * requests equal in number to shost->can_queue. If all of the
1734 * preallocated requests are already in use, then blk_get_request()
1735 * will sleep until an active command completes, freeing up a request.
1736 * Although waiting in an asynchronous interface is less than ideal, we
1737 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1738 * not expect an EWOULDBLOCK from this condition.
1740 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1741 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
1748 if (hp->cmd_len > BLK_MAX_CDB)
1749 req->cmd = long_cmdp;
1750 memcpy(req->cmd, cmd, hp->cmd_len);
1751 req->cmd_len = hp->cmd_len;
1754 rq->end_io_data = srp;
1755 req->retries = SG_DEFAULT_RETRIES;
1757 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1760 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1761 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1762 !sfp->parentdp->device->host->unchecked_isa_dma &&
1763 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1769 mutex_lock(&sfp->f_mutex);
1770 if (dxfer_len <= rsv_schp->bufflen &&
1772 sfp->res_in_use = 1;
1773 sg_link_reserve(sfp, srp, dxfer_len);
1774 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1775 res = -EBUSY; /* sfp->res_in_use == 1 */
1776 if (dxfer_len > rsv_schp->bufflen)
1778 mutex_unlock(&sfp->f_mutex);
1781 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1783 mutex_unlock(&sfp->f_mutex);
1787 mutex_unlock(&sfp->f_mutex);
1789 md->pages = req_schp->pages;
1790 md->page_order = req_schp->page_order;
1791 md->nr_entries = req_schp->k_use_sg;
1793 md->null_mapped = hp->dxferp ? 0 : 1;
1794 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1801 struct iovec *iov = NULL;
1804 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1808 iov_iter_truncate(&i, hp->dxfer_len);
1809 if (!iov_iter_count(&i)) {
1814 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1817 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1818 hp->dxfer_len, GFP_ATOMIC);
1824 req_schp->dio_in_use = 1;
1825 hp->info |= SG_INFO_DIRECT_IO;
1832 sg_finish_rem_req(Sg_request *srp)
1836 Sg_fd *sfp = srp->parentfp;
1837 Sg_scatter_hold *req_schp = &srp->data;
1839 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1840 "sg_finish_rem_req: res_used=%d\n",
1841 (int) srp->res_used));
1843 ret = blk_rq_unmap_user(srp->bio);
1846 scsi_req_free_cmd(scsi_req(srp->rq));
1847 blk_put_request(srp->rq);
1851 sg_unlink_reserve(sfp, srp);
1853 sg_remove_scat(sfp, req_schp);
1859 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1861 int sg_bufflen = tablesize * sizeof(struct page *);
1862 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1864 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1867 schp->sglist_len = sg_bufflen;
1868 return tablesize; /* number of scat_gath elements allocated */
1872 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1874 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1875 int sg_tablesize = sfp->parentdp->sg_tablesize;
1876 int blk_size = buff_size, order;
1877 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1878 struct sg_device *sdp = sfp->parentdp;
1883 ++blk_size; /* don't know why */
1884 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1885 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1886 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1887 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1888 buff_size, blk_size));
1890 /* N.B. ret_sz carried into this block ... */
1891 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1892 if (mx_sc_elems < 0)
1893 return mx_sc_elems; /* most likely -ENOMEM */
1895 num = scatter_elem_sz;
1896 if (unlikely(num != scatter_elem_sz_prev)) {
1897 if (num < PAGE_SIZE) {
1898 scatter_elem_sz = PAGE_SIZE;
1899 scatter_elem_sz_prev = PAGE_SIZE;
1901 scatter_elem_sz_prev = num;
1904 if (sdp->device->host->unchecked_isa_dma)
1905 gfp_mask |= GFP_DMA;
1907 order = get_order(num);
1909 ret_sz = 1 << (PAGE_SHIFT + order);
1911 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1912 k++, rem_sz -= ret_sz) {
1914 num = (rem_sz > scatter_elem_sz_prev) ?
1915 scatter_elem_sz_prev : rem_sz;
1917 schp->pages[k] = alloc_pages(gfp_mask, order);
1918 if (!schp->pages[k])
1921 if (num == scatter_elem_sz_prev) {
1922 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1923 scatter_elem_sz = ret_sz;
1924 scatter_elem_sz_prev = ret_sz;
1928 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1929 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1931 } /* end of for loop */
1933 schp->page_order = order;
1935 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1936 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1939 schp->bufflen = blk_size;
1940 if (rem_sz > 0) /* must have failed */
1944 for (i = 0; i < k; i++)
1945 __free_pages(schp->pages[i], order);
1954 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1956 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1957 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1958 if (schp->pages && schp->sglist_len > 0) {
1959 if (!schp->dio_in_use) {
1962 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1964 sg_printk(KERN_INFO, sfp->parentdp,
1965 "sg_remove_scat: k=%d, pg=0x%p\n",
1966 k, schp->pages[k]));
1967 __free_pages(schp->pages[k], schp->page_order);
1973 memset(schp, 0, sizeof (*schp));
1977 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1979 Sg_scatter_hold *schp = &srp->data;
1982 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1983 "sg_read_oxfer: num_read_xfer=%d\n",
1985 if ((!outp) || (num_read_xfer <= 0))
1988 num = 1 << (PAGE_SHIFT + schp->page_order);
1989 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1990 if (num > num_read_xfer) {
1991 if (__copy_to_user(outp, page_address(schp->pages[k]),
1996 if (__copy_to_user(outp, page_address(schp->pages[k]),
1999 num_read_xfer -= num;
2000 if (num_read_xfer <= 0)
2010 sg_build_reserve(Sg_fd * sfp, int req_size)
2012 Sg_scatter_hold *schp = &sfp->reserve;
2014 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2015 "sg_build_reserve: req_size=%d\n", req_size));
2017 if (req_size < PAGE_SIZE)
2018 req_size = PAGE_SIZE;
2019 if (0 == sg_build_indirect(schp, sfp, req_size))
2022 sg_remove_scat(sfp, schp);
2023 req_size >>= 1; /* divide by 2 */
2024 } while (req_size > (PAGE_SIZE / 2));
2028 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2030 Sg_scatter_hold *req_schp = &srp->data;
2031 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2035 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2036 "sg_link_reserve: size=%d\n", size));
2039 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2040 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2042 req_schp->k_use_sg = k + 1;
2043 req_schp->sglist_len = rsv_schp->sglist_len;
2044 req_schp->pages = rsv_schp->pages;
2046 req_schp->bufflen = size;
2047 req_schp->page_order = rsv_schp->page_order;
2053 if (k >= rsv_schp->k_use_sg)
2054 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2055 "sg_link_reserve: BAD size\n"));
2059 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2061 Sg_scatter_hold *req_schp = &srp->data;
2063 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2064 "sg_unlink_reserve: req->k_use_sg=%d\n",
2065 (int) req_schp->k_use_sg));
2066 req_schp->k_use_sg = 0;
2067 req_schp->bufflen = 0;
2068 req_schp->pages = NULL;
2069 req_schp->page_order = 0;
2070 req_schp->sglist_len = 0;
2072 /* Called without mutex lock to avoid deadlock */
2073 sfp->res_in_use = 0;
2077 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2080 unsigned long iflags;
2082 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2083 list_for_each_entry(resp, &sfp->rq_list, entry) {
2084 /* look for requests that are ready + not SG_IO owned */
2085 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2086 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2087 resp->done = 2; /* guard against other readers */
2088 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2092 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2096 /* always adds to end of list */
2098 sg_add_request(Sg_fd * sfp)
2101 unsigned long iflags;
2102 Sg_request *rp = sfp->req_arr;
2104 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2105 if (!list_empty(&sfp->rq_list)) {
2109 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2113 if (k >= SG_MAX_QUEUE)
2116 memset(rp, 0, sizeof (Sg_request));
2118 rp->header.duration = jiffies_to_msecs(jiffies);
2119 list_add_tail(&rp->entry, &sfp->rq_list);
2120 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2123 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2127 /* Return of 1 for found; 0 for not found */
2129 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2131 unsigned long iflags;
2134 if (!sfp || !srp || list_empty(&sfp->rq_list))
2136 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2137 if (!list_empty(&srp->entry)) {
2138 list_del(&srp->entry);
2139 srp->parentfp = NULL;
2142 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2147 sg_add_sfp(Sg_device * sdp)
2150 unsigned long iflags;
2153 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2155 return ERR_PTR(-ENOMEM);
2157 init_waitqueue_head(&sfp->read_wait);
2158 rwlock_init(&sfp->rq_list_lock);
2159 INIT_LIST_HEAD(&sfp->rq_list);
2160 kref_init(&sfp->f_ref);
2161 mutex_init(&sfp->f_mutex);
2162 sfp->timeout = SG_DEFAULT_TIMEOUT;
2163 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2164 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2165 sfp->cmd_q = SG_DEF_COMMAND_Q;
2166 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2167 sfp->parentdp = sdp;
2168 write_lock_irqsave(&sdp->sfd_lock, iflags);
2169 if (atomic_read(&sdp->detaching)) {
2170 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2172 return ERR_PTR(-ENODEV);
2174 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2175 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2176 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2177 "sg_add_sfp: sfp=0x%p\n", sfp));
2178 if (unlikely(sg_big_buff != def_reserved_size))
2179 sg_big_buff = def_reserved_size;
2181 bufflen = min_t(int, sg_big_buff,
2182 max_sectors_bytes(sdp->device->request_queue));
2183 sg_build_reserve(sfp, bufflen);
2184 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2185 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2186 sfp->reserve.bufflen,
2187 sfp->reserve.k_use_sg));
2189 kref_get(&sdp->d_ref);
2190 __module_get(THIS_MODULE);
2195 sg_remove_sfp_usercontext(struct work_struct *work)
2197 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2198 struct sg_device *sdp = sfp->parentdp;
2200 unsigned long iflags;
2202 /* Cleanup any responses which were never read(). */
2203 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2204 while (!list_empty(&sfp->rq_list)) {
2205 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2206 sg_finish_rem_req(srp);
2207 list_del(&srp->entry);
2208 srp->parentfp = NULL;
2210 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2212 if (sfp->reserve.bufflen > 0) {
2213 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2214 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2215 (int) sfp->reserve.bufflen,
2216 (int) sfp->reserve.k_use_sg));
2217 sg_remove_scat(sfp, &sfp->reserve);
2220 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2221 "sg_remove_sfp: sfp=0x%p\n", sfp));
2224 scsi_device_put(sdp->device);
2225 kref_put(&sdp->d_ref, sg_device_destroy);
2226 module_put(THIS_MODULE);
2230 sg_remove_sfp(struct kref *kref)
2232 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2233 struct sg_device *sdp = sfp->parentdp;
2234 unsigned long iflags;
2236 write_lock_irqsave(&sdp->sfd_lock, iflags);
2237 list_del(&sfp->sfd_siblings);
2238 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2240 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2241 schedule_work(&sfp->ew.work);
2244 #ifdef CONFIG_SCSI_PROC_FS
2246 sg_idr_max_id(int id, void *p, void *data)
2260 unsigned long iflags;
2262 read_lock_irqsave(&sg_index_lock, iflags);
2263 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2264 read_unlock_irqrestore(&sg_index_lock, iflags);
2265 return k + 1; /* origin 1 */
2269 /* must be called with sg_index_lock held */
2270 static Sg_device *sg_lookup_dev(int dev)
2272 return idr_find(&sg_index_idr, dev);
2278 struct sg_device *sdp;
2279 unsigned long flags;
2281 read_lock_irqsave(&sg_index_lock, flags);
2282 sdp = sg_lookup_dev(dev);
2284 sdp = ERR_PTR(-ENXIO);
2285 else if (atomic_read(&sdp->detaching)) {
2286 /* If sdp->detaching, then the refcount may already be 0, in
2287 * which case it would be a bug to do kref_get().
2289 sdp = ERR_PTR(-ENODEV);
2291 kref_get(&sdp->d_ref);
2292 read_unlock_irqrestore(&sg_index_lock, flags);
2297 #ifdef CONFIG_SCSI_PROC_FS
2298 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2300 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2301 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2302 size_t count, loff_t *off);
2303 static const struct file_operations adio_fops = {
2304 .owner = THIS_MODULE,
2305 .open = sg_proc_single_open_adio,
2307 .llseek = seq_lseek,
2308 .write = sg_proc_write_adio,
2309 .release = single_release,
2312 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2313 static ssize_t sg_proc_write_dressz(struct file *filp,
2314 const char __user *buffer, size_t count, loff_t *off);
2315 static const struct file_operations dressz_fops = {
2316 .owner = THIS_MODULE,
2317 .open = sg_proc_single_open_dressz,
2319 .llseek = seq_lseek,
2320 .write = sg_proc_write_dressz,
2321 .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_fops);
2363 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2364 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_fops);
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) atomic_read(&scsidp->device_busy),
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,
2535 (int) sdp->device->host->unchecked_isa_dma);
2536 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2537 (int) fp->cmd_q, (int) fp->force_packid,
2538 (int) fp->keep_orphan);
2539 list_for_each_entry(srp, &fp->rq_list, entry) {
2541 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2542 if (srp->res_used) {
2543 if (new_interface &&
2544 (SG_FLAG_MMAP_IO & hp->flags))
2549 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2555 blen = srp->data.bufflen;
2556 usg = srp->data.k_use_sg;
2557 seq_puts(s, srp->done ?
2558 ((1 == srp->done) ? "rcv:" : "fin:")
2560 seq_printf(s, " id=%d blen=%d",
2561 srp->header.pack_id, blen);
2563 seq_printf(s, " dur=%d", hp->duration);
2565 ms = jiffies_to_msecs(jiffies);
2566 seq_printf(s, " t_o/elap=%d/%d",
2567 (new_interface ? hp->timeout :
2568 jiffies_to_msecs(fp->timeout)),
2569 (ms > hp->duration ? ms - hp->duration : 0));
2571 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2572 (int) srp->data.cmd_opcode);
2574 if (list_empty(&fp->rq_list))
2575 seq_puts(s, " No requests active\n");
2576 read_unlock(&fp->rq_list_lock);
2580 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2582 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2584 unsigned long iflags;
2586 if (it && (0 == it->index))
2587 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2588 (int)it->max, sg_big_buff);
2590 read_lock_irqsave(&sg_index_lock, iflags);
2591 sdp = it ? sg_lookup_dev(it->index) : NULL;
2594 read_lock(&sdp->sfd_lock);
2595 if (!list_empty(&sdp->sfds)) {
2596 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2597 if (atomic_read(&sdp->detaching))
2598 seq_puts(s, "detaching pending close ");
2599 else if (sdp->device) {
2600 struct scsi_device *scsidp = sdp->device;
2602 seq_printf(s, "%d:%d:%d:%llu em=%d",
2603 scsidp->host->host_no,
2604 scsidp->channel, scsidp->id,
2606 scsidp->host->hostt->emulated);
2608 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2609 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2610 sg_proc_debug_helper(s, sdp);
2612 read_unlock(&sdp->sfd_lock);
2614 read_unlock_irqrestore(&sg_index_lock, iflags);
2618 #endif /* CONFIG_SCSI_PROC_FS */
2620 module_init(init_sg);
2621 module_exit(exit_sg);