3 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
4 * to allow user process control of SCSI devices.
5 * Development Sponsored by Killy Corp. NY NY
7 * Original driver (sg.c):
8 * Copyright (C) 1992 Lawrence Foard
9 * Version 2 and 3 extensions to driver:
10 * Copyright (C) 1998 - 2014 Douglas Gilbert
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
19 static int sg_version_num = 30536; /* 2 digits for each component */
20 #define SG_VERSION_STR "3.5.36"
23 * D. P. Gilbert (dgilbert@interlog.com), notes:
24 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
25 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
26 * (otherwise the macros compile to empty statements).
29 #include <linux/module.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/string.h>
36 #include <linux/errno.h>
37 #include <linux/mtio.h>
38 #include <linux/ioctl.h>
39 #include <linux/slab.h>
40 #include <linux/fcntl.h>
41 #include <linux/init.h>
42 #include <linux/poll.h>
43 #include <linux/moduleparam.h>
44 #include <linux/cdev.h>
45 #include <linux/idr.h>
46 #include <linux/seq_file.h>
47 #include <linux/blkdev.h>
48 #include <linux/delay.h>
49 #include <linux/blktrace_api.h>
50 #include <linux/mutex.h>
51 #include <linux/atomic.h>
52 #include <linux/ratelimit.h>
53 #include <linux/uio.h>
54 #include <linux/cred.h> /* for sg_check_file_access() */
57 #include <scsi/scsi_dbg.h>
58 #include <scsi/scsi_host.h>
59 #include <scsi/scsi_driver.h>
60 #include <scsi/scsi_ioctl.h>
63 #include "scsi_logging.h"
65 #ifdef CONFIG_SCSI_PROC_FS
66 #include <linux/proc_fs.h>
67 static char *sg_version_date = "20140603";
69 static int sg_proc_init(void);
72 #define SG_ALLOW_DIO_DEF 0
74 #define SG_MAX_DEVS 32768
76 /* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
78 * than 16 bytes are "variable length" whose length is a multiple of 4
80 #define SG_MAX_CDB_SIZE 252
82 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
84 int sg_big_buff = SG_DEF_RESERVED_SIZE;
85 /* N.B. This variable is readable and writeable via
86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
87 of this size (or less if there is not enough memory) will be reserved
88 for use by this file descriptor. [Deprecated usage: this variable is also
89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
90 the kernel (i.e. it is not a module).] */
91 static int def_reserved_size = -1; /* picks up init parameter */
92 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
94 static int scatter_elem_sz = SG_SCATTER_SZ;
95 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
97 #define SG_SECTOR_SZ 512
99 static int sg_add_device(struct device *, struct class_interface *);
100 static void sg_remove_device(struct device *, struct class_interface *);
102 static DEFINE_IDR(sg_index_idr);
103 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
106 static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
111 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
114 unsigned bufflen; /* Size of (aggregate) data buffer */
117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
118 unsigned char cmd_opcode; /* first byte of command */
121 struct sg_device; /* forward declarations */
124 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
125 struct list_head entry; /* list entry */
126 struct sg_fd *parentfp; /* NULL -> not in use */
127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
131 char orphan; /* 1 -> drop on sight, 0 -> normal */
132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
133 /* done protected by rq_list_lock */
134 char done; /* 0->before bh, 1->before read, 2->read */
137 struct execute_work ew;
140 typedef struct sg_fd { /* holds the state of a file descriptor */
141 struct list_head sfd_siblings; /* protected by device's sfd_lock */
142 struct sg_device *parentdp; /* owning device */
143 wait_queue_head_t read_wait; /* queue read until command done */
144 rwlock_t rq_list_lock; /* protect access to list in req_arr */
145 struct mutex f_mutex; /* protect against changes in this fd */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 struct list_head rq_list; /* head of request list */
150 struct fasync_struct *async_qp; /* used by asynchronous notification */
151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
152 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
156 char mmap_called; /* 0 -> mmap() never called on this fd */
157 char res_in_use; /* 1 -> 'reserve' array in use */
159 struct execute_work ew;
162 typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
165 struct mutex open_rel_lock; /* held when in open() or release() */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 struct list_head sfds;
169 rwlock_t sfd_lock; /* protect access to sfd list */
170 atomic_t detaching; /* 0->device usable, 1->device detaching */
171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174 struct gendisk *disk;
175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
179 /* tasklet or soft irq callback */
180 static void sg_rq_end_io(struct request *rq, blk_status_t status);
181 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182 static int sg_finish_rem_req(Sg_request * srp);
183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, int sg_io_owned, Sg_request **o_srp);
189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196 static Sg_fd *sg_add_sfp(Sg_device * sdp);
197 static void sg_remove_sfp(struct kref *);
198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy);
199 static Sg_request *sg_add_request(Sg_fd * sfp);
200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201 static Sg_device *sg_get_dev(int dev);
202 static void sg_device_destroy(struct kref *kref);
204 #define SZ_SG_HEADER sizeof(struct sg_header)
205 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
206 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
207 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
209 #define sg_printk(prefix, sdp, fmt, a...) \
210 sdev_prefix_printk(prefix, (sdp)->device, \
211 (sdp)->disk->disk_name, fmt, ##a)
214 * The SCSI interfaces that use read() and write() as an asynchronous variant of
215 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
216 * to trigger read() and write() calls from various contexts with elevated
217 * privileges. This can lead to kernel memory corruption (e.g. if these
218 * interfaces are called through splice()) and privilege escalation inside
219 * userspace (e.g. if a process with access to such a device passes a file
220 * descriptor to a SUID binary as stdin/stdout/stderr).
222 * This function provides protection for the legacy API by restricting the
225 static int sg_check_file_access(struct file *filp, const char *caller)
227 if (filp->f_cred != current_real_cred()) {
228 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
229 caller, task_tgid_vnr(current), current->comm);
232 if (uaccess_kernel()) {
233 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
234 caller, task_tgid_vnr(current), current->comm);
240 static int sg_allow_access(struct file *filp, unsigned char *cmd)
242 struct sg_fd *sfp = filp->private_data;
244 if (sfp->parentdp->device->type == TYPE_SCANNER)
247 return blk_verify_command(cmd, filp->f_mode);
251 open_wait(Sg_device *sdp, int flags)
255 if (flags & O_EXCL) {
256 while (sdp->open_cnt > 0) {
257 mutex_unlock(&sdp->open_rel_lock);
258 retval = wait_event_interruptible(sdp->open_wait,
259 (atomic_read(&sdp->detaching) ||
261 mutex_lock(&sdp->open_rel_lock);
263 if (retval) /* -ERESTARTSYS */
265 if (atomic_read(&sdp->detaching))
269 while (sdp->exclude) {
270 mutex_unlock(&sdp->open_rel_lock);
271 retval = wait_event_interruptible(sdp->open_wait,
272 (atomic_read(&sdp->detaching) ||
274 mutex_lock(&sdp->open_rel_lock);
276 if (retval) /* -ERESTARTSYS */
278 if (atomic_read(&sdp->detaching))
286 /* Returns 0 on success, else a negated errno value */
288 sg_open(struct inode *inode, struct file *filp)
290 int dev = iminor(inode);
291 int flags = filp->f_flags;
292 struct request_queue *q;
297 nonseekable_open(inode, filp);
298 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
299 return -EPERM; /* Can't lock it with read only access */
300 sdp = sg_get_dev(dev);
304 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
305 "sg_open: flags=0x%x\n", flags));
307 /* This driver's module count bumped by fops_get in <linux/fs.h> */
308 /* Prevent the device driver from vanishing while we sleep */
309 retval = scsi_device_get(sdp->device);
313 retval = scsi_autopm_get_device(sdp->device);
317 /* scsi_block_when_processing_errors() may block so bypass
318 * check if O_NONBLOCK. Permits SCSI commands to be issued
319 * during error recovery. Tread carefully. */
320 if (!((flags & O_NONBLOCK) ||
321 scsi_block_when_processing_errors(sdp->device))) {
323 /* we are in error recovery for this device */
327 mutex_lock(&sdp->open_rel_lock);
328 if (flags & O_NONBLOCK) {
329 if (flags & O_EXCL) {
330 if (sdp->open_cnt > 0) {
332 goto error_mutex_locked;
337 goto error_mutex_locked;
341 retval = open_wait(sdp, flags);
342 if (retval) /* -ERESTARTSYS or -ENODEV */
343 goto error_mutex_locked;
346 /* N.B. at this point we are holding the open_rel_lock */
350 if (sdp->open_cnt < 1) { /* no existing opens */
352 q = sdp->device->request_queue;
353 sdp->sg_tablesize = queue_max_segments(q);
355 sfp = sg_add_sfp(sdp);
357 retval = PTR_ERR(sfp);
361 filp->private_data = sfp;
363 mutex_unlock(&sdp->open_rel_lock);
367 kref_put(&sdp->d_ref, sg_device_destroy);
371 if (flags & O_EXCL) {
372 sdp->exclude = false; /* undo if error */
373 wake_up_interruptible(&sdp->open_wait);
376 mutex_unlock(&sdp->open_rel_lock);
378 scsi_autopm_put_device(sdp->device);
380 scsi_device_put(sdp->device);
384 /* Release resources associated with a successful sg_open()
385 * Returns 0 on success, else a negated errno value */
387 sg_release(struct inode *inode, struct file *filp)
392 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
394 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
396 mutex_lock(&sdp->open_rel_lock);
397 scsi_autopm_put_device(sdp->device);
398 kref_put(&sfp->f_ref, sg_remove_sfp);
401 /* possibly many open()s waiting on exlude clearing, start many;
402 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
404 sdp->exclude = false;
405 wake_up_interruptible_all(&sdp->open_wait);
406 } else if (0 == sdp->open_cnt) {
407 wake_up_interruptible(&sdp->open_wait);
409 mutex_unlock(&sdp->open_rel_lock);
414 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
419 int req_pack_id = -1;
422 struct sg_header *old_hdr = NULL;
426 * This could cause a response to be stranded. Close the associated
427 * file descriptor to free up any resources being held.
429 retval = sg_check_file_access(filp, __func__);
433 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
435 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
436 "sg_read: count=%d\n", (int) count));
438 if (!access_ok(VERIFY_WRITE, buf, count))
440 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
441 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
444 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
448 if (old_hdr->reply_len < 0) {
449 if (count >= SZ_SG_IO_HDR) {
450 sg_io_hdr_t *new_hdr;
451 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
456 retval =__copy_from_user
457 (new_hdr, buf, SZ_SG_IO_HDR);
458 req_pack_id = new_hdr->pack_id;
466 req_pack_id = old_hdr->pack_id;
468 srp = sg_get_rq_mark(sfp, req_pack_id, &busy);
469 if (!srp) { /* now wait on packet to arrive */
470 if (filp->f_flags & O_NONBLOCK) {
474 retval = wait_event_interruptible(sfp->read_wait,
475 ((srp = sg_get_rq_mark(sfp, req_pack_id, &busy)) ||
476 (!busy && atomic_read(&sdp->detaching))));
478 /* signal or detaching */
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(VERIFY_READ, 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(VERIFY_READ, 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(VERIFY_READ, 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_end_request_all(srp->rq, BLK_STS_IOERR);
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(VERIFY_WRITE, 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,
932 write_lock_irq(&sfp->rq_list_lock);
935 write_unlock_irq(&sfp->rq_list_lock);
936 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
937 return (result < 0) ? result : 0;
940 write_unlock_irq(&sfp->rq_list_lock);
941 return result; /* -ERESTARTSYS because signal hit process */
943 result = get_user(val, ip);
948 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
949 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
951 sfp->timeout_user = val;
952 sfp->timeout = mult_frac(val, HZ, USER_HZ);
955 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
956 /* strange ..., for backward compatibility */
957 return sfp->timeout_user;
958 case SG_SET_FORCE_LOW_DMA:
960 * N.B. This ioctl never worked properly, but failed to
961 * return an error value. So returning '0' to keep compability
962 * with legacy applications.
966 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
968 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
971 sg_scsi_id_t __user *sg_idp = p;
973 if (atomic_read(&sdp->detaching))
975 __put_user((int) sdp->device->host->host_no,
977 __put_user((int) sdp->device->channel,
979 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
980 __put_user((int) sdp->device->lun, &sg_idp->lun);
981 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
982 __put_user((short) sdp->device->host->cmd_per_lun,
983 &sg_idp->h_cmd_per_lun);
984 __put_user((short) sdp->device->queue_depth,
985 &sg_idp->d_queue_depth);
986 __put_user(0, &sg_idp->unused[0]);
987 __put_user(0, &sg_idp->unused[1]);
990 case SG_SET_FORCE_PACK_ID:
991 result = get_user(val, ip);
994 sfp->force_packid = val ? 1 : 0;
997 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
999 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1000 list_for_each_entry(srp, &sfp->rq_list, entry) {
1001 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1002 read_unlock_irqrestore(&sfp->rq_list_lock,
1004 __put_user(srp->header.pack_id, ip);
1008 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1011 case SG_GET_NUM_WAITING:
1012 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1014 list_for_each_entry(srp, &sfp->rq_list, entry) {
1015 if ((1 == srp->done) && (!srp->sg_io_owned))
1018 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1019 return put_user(val, ip);
1020 case SG_GET_SG_TABLESIZE:
1021 return put_user(sdp->sg_tablesize, ip);
1022 case SG_SET_RESERVED_SIZE:
1023 result = get_user(val, ip);
1028 val = min_t(int, val,
1029 max_sectors_bytes(sdp->device->request_queue));
1030 mutex_lock(&sfp->f_mutex);
1031 if (val != sfp->reserve.bufflen) {
1032 if (sfp->mmap_called ||
1034 mutex_unlock(&sfp->f_mutex);
1038 sg_remove_scat(sfp, &sfp->reserve);
1039 sg_build_reserve(sfp, val);
1041 mutex_unlock(&sfp->f_mutex);
1043 case SG_GET_RESERVED_SIZE:
1044 val = min_t(int, sfp->reserve.bufflen,
1045 max_sectors_bytes(sdp->device->request_queue));
1046 return put_user(val, ip);
1047 case SG_SET_COMMAND_Q:
1048 result = get_user(val, ip);
1051 sfp->cmd_q = val ? 1 : 0;
1053 case SG_GET_COMMAND_Q:
1054 return put_user((int) sfp->cmd_q, ip);
1055 case SG_SET_KEEP_ORPHAN:
1056 result = get_user(val, ip);
1059 sfp->keep_orphan = val;
1061 case SG_GET_KEEP_ORPHAN:
1062 return put_user((int) sfp->keep_orphan, ip);
1063 case SG_NEXT_CMD_LEN:
1064 result = get_user(val, ip);
1067 if (val > SG_MAX_CDB_SIZE)
1069 sfp->next_cmd_len = (val > 0) ? val : 0;
1071 case SG_GET_VERSION_NUM:
1072 return put_user(sg_version_num, ip);
1073 case SG_GET_ACCESS_COUNT:
1074 /* faked - we don't have a real access count anymore */
1075 val = (sdp->device ? 1 : 0);
1076 return put_user(val, ip);
1077 case SG_GET_REQUEST_TABLE:
1078 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1081 sg_req_info_t *rinfo;
1083 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1087 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1088 sg_fill_request_table(sfp, rinfo);
1089 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1090 result = __copy_to_user(p, rinfo,
1091 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1092 result = result ? -EFAULT : 0;
1096 case SG_EMULATED_HOST:
1097 if (atomic_read(&sdp->detaching))
1099 return put_user(sdp->device->host->hostt->emulated, ip);
1100 case SCSI_IOCTL_SEND_COMMAND:
1101 if (atomic_read(&sdp->detaching))
1103 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1105 result = get_user(val, ip);
1108 sdp->sgdebug = (char) val;
1111 return put_user(max_sectors_bytes(sdp->device->request_queue),
1114 return blk_trace_setup(sdp->device->request_queue,
1115 sdp->disk->disk_name,
1116 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1119 return blk_trace_startstop(sdp->device->request_queue, 1);
1121 return blk_trace_startstop(sdp->device->request_queue, 0);
1122 case BLKTRACETEARDOWN:
1123 return blk_trace_remove(sdp->device->request_queue);
1124 case SCSI_IOCTL_GET_IDLUN:
1125 case SCSI_IOCTL_GET_BUS_NUMBER:
1126 case SCSI_IOCTL_PROBE_HOST:
1127 case SG_GET_TRANSFORM:
1129 if (atomic_read(&sdp->detaching))
1134 return -EPERM; /* don't know so take safe approach */
1138 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1139 cmd_in, filp->f_flags & O_NDELAY);
1142 return scsi_ioctl(sdp->device, cmd_in, p);
1145 #ifdef CONFIG_COMPAT
1146 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1150 struct scsi_device *sdev;
1152 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1156 if (sdev->host->hostt->compat_ioctl) {
1159 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1164 return -ENOIOCTLCMD;
1169 sg_poll(struct file *filp, poll_table * wait)
1176 unsigned long iflags;
1178 sfp = filp->private_data;
1181 sdp = sfp->parentdp;
1184 poll_wait(filp, &sfp->read_wait, wait);
1185 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1186 list_for_each_entry(srp, &sfp->rq_list, entry) {
1187 /* if any read waiting, flag it */
1188 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1189 res = EPOLLIN | EPOLLRDNORM;
1192 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1194 if (atomic_read(&sdp->detaching))
1196 else if (!sfp->cmd_q) {
1198 res |= EPOLLOUT | EPOLLWRNORM;
1199 } else if (count < SG_MAX_QUEUE)
1200 res |= EPOLLOUT | EPOLLWRNORM;
1201 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1202 "sg_poll: res=0x%x\n", (__force u32) res));
1207 sg_fasync(int fd, struct file *filp, int mode)
1212 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1214 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1215 "sg_fasync: mode=%d\n", mode));
1217 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1221 sg_vma_fault(struct vm_fault *vmf)
1223 struct vm_area_struct *vma = vmf->vma;
1225 unsigned long offset, len, sa;
1226 Sg_scatter_hold *rsv_schp;
1229 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1230 return VM_FAULT_SIGBUS;
1231 rsv_schp = &sfp->reserve;
1232 offset = vmf->pgoff << PAGE_SHIFT;
1233 if (offset >= rsv_schp->bufflen)
1234 return VM_FAULT_SIGBUS;
1235 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1236 "sg_vma_fault: offset=%lu, scatg=%d\n",
1237 offset, rsv_schp->k_use_sg));
1239 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1240 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1241 len = vma->vm_end - sa;
1242 len = (len < length) ? len : length;
1244 struct page *page = nth_page(rsv_schp->pages[k],
1245 offset >> PAGE_SHIFT);
1246 get_page(page); /* increment page count */
1248 return 0; /* success */
1254 return VM_FAULT_SIGBUS;
1257 static const struct vm_operations_struct sg_mmap_vm_ops = {
1258 .fault = sg_vma_fault,
1262 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1265 unsigned long req_sz, len, sa;
1266 Sg_scatter_hold *rsv_schp;
1270 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1272 req_sz = vma->vm_end - vma->vm_start;
1273 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1274 "sg_mmap starting, vm_start=%p, len=%d\n",
1275 (void *) vma->vm_start, (int) req_sz));
1277 return -EINVAL; /* want no offset */
1278 rsv_schp = &sfp->reserve;
1279 mutex_lock(&sfp->f_mutex);
1280 if (req_sz > rsv_schp->bufflen) {
1281 ret = -ENOMEM; /* cannot map more than reserved buffer */
1286 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1287 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1288 len = vma->vm_end - sa;
1289 len = (len < length) ? len : length;
1293 sfp->mmap_called = 1;
1294 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1295 vma->vm_private_data = sfp;
1296 vma->vm_ops = &sg_mmap_vm_ops;
1298 mutex_unlock(&sfp->f_mutex);
1303 sg_rq_end_io_usercontext(struct work_struct *work)
1305 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1306 struct sg_fd *sfp = srp->parentfp;
1308 sg_finish_rem_req(srp);
1309 sg_remove_request(sfp, srp);
1310 kref_put(&sfp->f_ref, sg_remove_sfp);
1314 * This function is a "bottom half" handler that is called by the mid
1315 * level when a command is completed (or has failed).
1318 sg_rq_end_io(struct request *rq, blk_status_t status)
1320 struct sg_request *srp = rq->end_io_data;
1321 struct scsi_request *req = scsi_req(rq);
1324 unsigned long iflags;
1327 int result, resid, done = 1;
1329 if (WARN_ON(srp->done != 0))
1332 sfp = srp->parentfp;
1333 if (WARN_ON(sfp == NULL))
1336 sdp = sfp->parentdp;
1337 if (unlikely(atomic_read(&sdp->detaching)))
1338 pr_info("%s: device detaching\n", __func__);
1341 result = req->result;
1342 resid = req->resid_len;
1344 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1345 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1346 srp->header.pack_id, result));
1347 srp->header.resid = resid;
1348 ms = jiffies_to_msecs(jiffies);
1349 srp->header.duration = (ms > srp->header.duration) ?
1350 (ms - srp->header.duration) : 0;
1352 struct scsi_sense_hdr sshdr;
1354 srp->header.status = 0xff & result;
1355 srp->header.masked_status = status_byte(result);
1356 srp->header.msg_status = msg_byte(result);
1357 srp->header.host_status = host_byte(result);
1358 srp->header.driver_status = driver_byte(result);
1359 if ((sdp->sgdebug > 0) &&
1360 ((CHECK_CONDITION == srp->header.masked_status) ||
1361 (COMMAND_TERMINATED == srp->header.masked_status)))
1362 __scsi_print_sense(sdp->device, __func__, sense,
1363 SCSI_SENSE_BUFFERSIZE);
1365 /* Following if statement is a patch supplied by Eric Youngdale */
1366 if (driver_byte(result) != 0
1367 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1368 && !scsi_sense_is_deferred(&sshdr)
1369 && sshdr.sense_key == UNIT_ATTENTION
1370 && sdp->device->removable) {
1371 /* Detected possible disc change. Set the bit - this */
1372 /* may be used if there are filesystems using this device */
1373 sdp->device->changed = 1;
1378 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1380 /* Rely on write phase to clean out srp status values, so no "else" */
1383 * Free the request as soon as it is complete so that its resources
1384 * can be reused without waiting for userspace to read() the
1385 * result. But keep the associated bio (if any) around until
1386 * blk_rq_unmap_user() can be called from user context.
1389 scsi_req_free_cmd(scsi_req(rq));
1390 __blk_put_request(rq->q, rq);
1392 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1393 if (unlikely(srp->orphan)) {
1394 if (sfp->keep_orphan)
1395 srp->sg_io_owned = 0;
1400 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1403 /* Now wake up any sg_read() that is waiting for this
1406 wake_up_interruptible(&sfp->read_wait);
1407 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1408 kref_put(&sfp->f_ref, sg_remove_sfp);
1410 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1411 schedule_work(&srp->ew.work);
1415 static const struct file_operations sg_fops = {
1416 .owner = THIS_MODULE,
1420 .unlocked_ioctl = sg_ioctl,
1421 #ifdef CONFIG_COMPAT
1422 .compat_ioctl = sg_compat_ioctl,
1426 .release = sg_release,
1427 .fasync = sg_fasync,
1428 .llseek = no_llseek,
1431 static struct class *sg_sysfs_class;
1433 static int sg_sysfs_valid = 0;
1436 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1438 struct request_queue *q = scsidp->request_queue;
1440 unsigned long iflags;
1444 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1446 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1447 "failure\n", __func__);
1448 return ERR_PTR(-ENOMEM);
1451 idr_preload(GFP_KERNEL);
1452 write_lock_irqsave(&sg_index_lock, iflags);
1454 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1456 if (error == -ENOSPC) {
1457 sdev_printk(KERN_WARNING, scsidp,
1458 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1459 scsidp->type, SG_MAX_DEVS - 1);
1462 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1463 "allocation Sg_device failure: %d\n",
1470 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1471 "sg_alloc: dev=%d \n", k));
1472 sprintf(disk->disk_name, "sg%d", k);
1473 disk->first_minor = k;
1475 sdp->device = scsidp;
1476 mutex_init(&sdp->open_rel_lock);
1477 INIT_LIST_HEAD(&sdp->sfds);
1478 init_waitqueue_head(&sdp->open_wait);
1479 atomic_set(&sdp->detaching, 0);
1480 rwlock_init(&sdp->sfd_lock);
1481 sdp->sg_tablesize = queue_max_segments(q);
1483 kref_init(&sdp->d_ref);
1487 write_unlock_irqrestore(&sg_index_lock, iflags);
1492 return ERR_PTR(error);
1498 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1500 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1501 struct gendisk *disk;
1502 Sg_device *sdp = NULL;
1503 struct cdev * cdev = NULL;
1505 unsigned long iflags;
1507 disk = alloc_disk(1);
1509 pr_warn("%s: alloc_disk failed\n", __func__);
1512 disk->major = SCSI_GENERIC_MAJOR;
1515 cdev = cdev_alloc();
1517 pr_warn("%s: cdev_alloc failed\n", __func__);
1520 cdev->owner = THIS_MODULE;
1521 cdev->ops = &sg_fops;
1523 sdp = sg_alloc(disk, scsidp);
1525 pr_warn("%s: sg_alloc failed\n", __func__);
1526 error = PTR_ERR(sdp);
1530 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1535 if (sg_sysfs_valid) {
1536 struct device *sg_class_member;
1538 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1539 MKDEV(SCSI_GENERIC_MAJOR,
1541 sdp, "%s", disk->disk_name);
1542 if (IS_ERR(sg_class_member)) {
1543 pr_err("%s: device_create failed\n", __func__);
1544 error = PTR_ERR(sg_class_member);
1547 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1548 &sg_class_member->kobj, "generic");
1550 pr_err("%s: unable to make symlink 'generic' back "
1551 "to sg%d\n", __func__, sdp->index);
1553 pr_warn("%s: sg_sys Invalid\n", __func__);
1555 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1556 "type %d\n", sdp->index, scsidp->type);
1558 dev_set_drvdata(cl_dev, sdp);
1563 write_lock_irqsave(&sg_index_lock, iflags);
1564 idr_remove(&sg_index_idr, sdp->index);
1565 write_unlock_irqrestore(&sg_index_lock, iflags);
1576 sg_device_destroy(struct kref *kref)
1578 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1579 unsigned long flags;
1581 /* CAUTION! Note that the device can still be found via idr_find()
1582 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1583 * any other cleanup.
1586 write_lock_irqsave(&sg_index_lock, flags);
1587 idr_remove(&sg_index_idr, sdp->index);
1588 write_unlock_irqrestore(&sg_index_lock, flags);
1591 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1593 put_disk(sdp->disk);
1598 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1600 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1601 Sg_device *sdp = dev_get_drvdata(cl_dev);
1602 unsigned long iflags;
1608 /* want sdp->detaching non-zero as soon as possible */
1609 val = atomic_inc_return(&sdp->detaching);
1611 return; /* only want to do following once per device */
1613 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1616 read_lock_irqsave(&sdp->sfd_lock, iflags);
1617 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1618 wake_up_interruptible_all(&sfp->read_wait);
1619 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1621 wake_up_interruptible_all(&sdp->open_wait);
1622 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1624 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1625 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1626 cdev_del(sdp->cdev);
1629 kref_put(&sdp->d_ref, sg_device_destroy);
1632 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1633 module_param_named(def_reserved_size, def_reserved_size, int,
1635 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1637 MODULE_AUTHOR("Douglas Gilbert");
1638 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1639 MODULE_LICENSE("GPL");
1640 MODULE_VERSION(SG_VERSION_STR);
1641 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1643 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1644 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1645 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1646 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1653 if (scatter_elem_sz < PAGE_SIZE) {
1654 scatter_elem_sz = PAGE_SIZE;
1655 scatter_elem_sz_prev = scatter_elem_sz;
1657 if (def_reserved_size >= 0)
1658 sg_big_buff = def_reserved_size;
1660 def_reserved_size = sg_big_buff;
1662 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1666 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1667 if ( IS_ERR(sg_sysfs_class) ) {
1668 rc = PTR_ERR(sg_sysfs_class);
1672 rc = scsi_register_interface(&sg_interface);
1674 #ifdef CONFIG_SCSI_PROC_FS
1676 #endif /* CONFIG_SCSI_PROC_FS */
1679 class_destroy(sg_sysfs_class);
1681 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1688 #ifdef CONFIG_SCSI_PROC_FS
1689 remove_proc_subtree("scsi/sg", NULL);
1690 #endif /* CONFIG_SCSI_PROC_FS */
1691 scsi_unregister_interface(&sg_interface);
1692 class_destroy(sg_sysfs_class);
1694 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1696 idr_destroy(&sg_index_idr);
1700 sg_start_req(Sg_request *srp, unsigned char *cmd)
1704 struct scsi_request *req;
1705 Sg_fd *sfp = srp->parentfp;
1706 sg_io_hdr_t *hp = &srp->header;
1707 int dxfer_len = (int) hp->dxfer_len;
1708 int dxfer_dir = hp->dxfer_direction;
1709 unsigned int iov_count = hp->iovec_count;
1710 Sg_scatter_hold *req_schp = &srp->data;
1711 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1712 struct request_queue *q = sfp->parentdp->device->request_queue;
1713 struct rq_map_data *md, map_data;
1714 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1715 unsigned char *long_cmdp = NULL;
1717 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1718 "sg_start_req: dxfer_len=%d\n",
1721 if (hp->cmd_len > BLK_MAX_CDB) {
1722 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1730 * With scsi-mq enabled, there are a fixed number of preallocated
1731 * requests equal in number to shost->can_queue. If all of the
1732 * preallocated requests are already in use, then blk_get_request()
1733 * will sleep until an active command completes, freeing up a request.
1734 * Although waiting in an asynchronous interface is less than ideal, we
1735 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1736 * not expect an EWOULDBLOCK from this condition.
1738 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1739 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
1746 if (hp->cmd_len > BLK_MAX_CDB)
1747 req->cmd = long_cmdp;
1748 memcpy(req->cmd, cmd, hp->cmd_len);
1749 req->cmd_len = hp->cmd_len;
1752 rq->end_io_data = srp;
1753 req->retries = SG_DEFAULT_RETRIES;
1755 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1758 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1759 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1760 !sfp->parentdp->device->host->unchecked_isa_dma &&
1761 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1767 mutex_lock(&sfp->f_mutex);
1768 if (dxfer_len <= rsv_schp->bufflen &&
1770 sfp->res_in_use = 1;
1771 sg_link_reserve(sfp, srp, dxfer_len);
1772 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1773 res = -EBUSY; /* sfp->res_in_use == 1 */
1774 if (dxfer_len > rsv_schp->bufflen)
1776 mutex_unlock(&sfp->f_mutex);
1779 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1781 mutex_unlock(&sfp->f_mutex);
1785 mutex_unlock(&sfp->f_mutex);
1787 md->pages = req_schp->pages;
1788 md->page_order = req_schp->page_order;
1789 md->nr_entries = req_schp->k_use_sg;
1791 md->null_mapped = hp->dxferp ? 0 : 1;
1792 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1799 struct iovec *iov = NULL;
1802 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1806 iov_iter_truncate(&i, hp->dxfer_len);
1807 if (!iov_iter_count(&i)) {
1812 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1815 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1816 hp->dxfer_len, GFP_ATOMIC);
1822 req_schp->dio_in_use = 1;
1823 hp->info |= SG_INFO_DIRECT_IO;
1830 sg_finish_rem_req(Sg_request *srp)
1834 Sg_fd *sfp = srp->parentfp;
1835 Sg_scatter_hold *req_schp = &srp->data;
1837 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1838 "sg_finish_rem_req: res_used=%d\n",
1839 (int) srp->res_used));
1841 ret = blk_rq_unmap_user(srp->bio);
1844 scsi_req_free_cmd(scsi_req(srp->rq));
1845 blk_put_request(srp->rq);
1849 sg_unlink_reserve(sfp, srp);
1851 sg_remove_scat(sfp, req_schp);
1857 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1859 int sg_bufflen = tablesize * sizeof(struct page *);
1860 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1862 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1865 schp->sglist_len = sg_bufflen;
1866 return tablesize; /* number of scat_gath elements allocated */
1870 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1872 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1873 int sg_tablesize = sfp->parentdp->sg_tablesize;
1874 int blk_size = buff_size, order;
1875 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1876 struct sg_device *sdp = sfp->parentdp;
1881 ++blk_size; /* don't know why */
1882 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1883 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1884 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1885 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1886 buff_size, blk_size));
1888 /* N.B. ret_sz carried into this block ... */
1889 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1890 if (mx_sc_elems < 0)
1891 return mx_sc_elems; /* most likely -ENOMEM */
1893 num = scatter_elem_sz;
1894 if (unlikely(num != scatter_elem_sz_prev)) {
1895 if (num < PAGE_SIZE) {
1896 scatter_elem_sz = PAGE_SIZE;
1897 scatter_elem_sz_prev = PAGE_SIZE;
1899 scatter_elem_sz_prev = num;
1902 if (sdp->device->host->unchecked_isa_dma)
1903 gfp_mask |= GFP_DMA;
1905 order = get_order(num);
1907 ret_sz = 1 << (PAGE_SHIFT + order);
1909 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1910 k++, rem_sz -= ret_sz) {
1912 num = (rem_sz > scatter_elem_sz_prev) ?
1913 scatter_elem_sz_prev : rem_sz;
1915 schp->pages[k] = alloc_pages(gfp_mask, order);
1916 if (!schp->pages[k])
1919 if (num == scatter_elem_sz_prev) {
1920 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1921 scatter_elem_sz = ret_sz;
1922 scatter_elem_sz_prev = ret_sz;
1926 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1927 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1929 } /* end of for loop */
1931 schp->page_order = order;
1933 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1934 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1937 schp->bufflen = blk_size;
1938 if (rem_sz > 0) /* must have failed */
1942 for (i = 0; i < k; i++)
1943 __free_pages(schp->pages[i], order);
1952 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1954 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1955 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1956 if (schp->pages && schp->sglist_len > 0) {
1957 if (!schp->dio_in_use) {
1960 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1962 sg_printk(KERN_INFO, sfp->parentdp,
1963 "sg_remove_scat: k=%d, pg=0x%p\n",
1964 k, schp->pages[k]));
1965 __free_pages(schp->pages[k], schp->page_order);
1971 memset(schp, 0, sizeof (*schp));
1975 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1977 Sg_scatter_hold *schp = &srp->data;
1980 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1981 "sg_read_oxfer: num_read_xfer=%d\n",
1983 if ((!outp) || (num_read_xfer <= 0))
1986 num = 1 << (PAGE_SHIFT + schp->page_order);
1987 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1988 if (num > num_read_xfer) {
1989 if (__copy_to_user(outp, page_address(schp->pages[k]),
1994 if (__copy_to_user(outp, page_address(schp->pages[k]),
1997 num_read_xfer -= num;
1998 if (num_read_xfer <= 0)
2008 sg_build_reserve(Sg_fd * sfp, int req_size)
2010 Sg_scatter_hold *schp = &sfp->reserve;
2012 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2013 "sg_build_reserve: req_size=%d\n", req_size));
2015 if (req_size < PAGE_SIZE)
2016 req_size = PAGE_SIZE;
2017 if (0 == sg_build_indirect(schp, sfp, req_size))
2020 sg_remove_scat(sfp, schp);
2021 req_size >>= 1; /* divide by 2 */
2022 } while (req_size > (PAGE_SIZE / 2));
2026 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2028 Sg_scatter_hold *req_schp = &srp->data;
2029 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2033 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2034 "sg_link_reserve: size=%d\n", size));
2037 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2038 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2040 req_schp->k_use_sg = k + 1;
2041 req_schp->sglist_len = rsv_schp->sglist_len;
2042 req_schp->pages = rsv_schp->pages;
2044 req_schp->bufflen = size;
2045 req_schp->page_order = rsv_schp->page_order;
2051 if (k >= rsv_schp->k_use_sg)
2052 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2053 "sg_link_reserve: BAD size\n"));
2057 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2059 Sg_scatter_hold *req_schp = &srp->data;
2061 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2062 "sg_unlink_reserve: req->k_use_sg=%d\n",
2063 (int) req_schp->k_use_sg));
2064 req_schp->k_use_sg = 0;
2065 req_schp->bufflen = 0;
2066 req_schp->pages = NULL;
2067 req_schp->page_order = 0;
2068 req_schp->sglist_len = 0;
2070 /* Called without mutex lock to avoid deadlock */
2071 sfp->res_in_use = 0;
2075 sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy)
2078 unsigned long iflags;
2081 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2082 list_for_each_entry(resp, &sfp->rq_list, entry) {
2083 /* look for requests that are not SG_IO owned */
2084 if ((!resp->sg_io_owned) &&
2085 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2086 switch (resp->done) {
2087 case 0: /* request active */
2090 case 1: /* request done; response ready to return */
2091 resp->done = 2; /* guard against other readers */
2092 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2094 case 2: /* response already being returned */
2099 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2103 /* always adds to end of list */
2105 sg_add_request(Sg_fd * sfp)
2108 unsigned long iflags;
2109 Sg_request *rp = sfp->req_arr;
2111 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2112 if (!list_empty(&sfp->rq_list)) {
2116 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2120 if (k >= SG_MAX_QUEUE)
2123 memset(rp, 0, sizeof (Sg_request));
2125 rp->header.duration = jiffies_to_msecs(jiffies);
2126 list_add_tail(&rp->entry, &sfp->rq_list);
2127 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2130 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2134 /* Return of 1 for found; 0 for not found */
2136 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2138 unsigned long iflags;
2141 if (!sfp || !srp || list_empty(&sfp->rq_list))
2143 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2144 if (!list_empty(&srp->entry)) {
2145 list_del(&srp->entry);
2146 srp->parentfp = NULL;
2149 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2152 * If the device is detaching, wakeup any readers in case we just
2153 * removed the last response, which would leave nothing for them to
2154 * return other than -ENODEV.
2156 if (unlikely(atomic_read(&sfp->parentdp->detaching)))
2157 wake_up_interruptible_all(&sfp->read_wait);
2163 sg_add_sfp(Sg_device * sdp)
2166 unsigned long iflags;
2169 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2171 return ERR_PTR(-ENOMEM);
2173 init_waitqueue_head(&sfp->read_wait);
2174 rwlock_init(&sfp->rq_list_lock);
2175 INIT_LIST_HEAD(&sfp->rq_list);
2176 kref_init(&sfp->f_ref);
2177 mutex_init(&sfp->f_mutex);
2178 sfp->timeout = SG_DEFAULT_TIMEOUT;
2179 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2180 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2181 sfp->cmd_q = SG_DEF_COMMAND_Q;
2182 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2183 sfp->parentdp = sdp;
2184 write_lock_irqsave(&sdp->sfd_lock, iflags);
2185 if (atomic_read(&sdp->detaching)) {
2186 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2188 return ERR_PTR(-ENODEV);
2190 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2191 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2192 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2193 "sg_add_sfp: sfp=0x%p\n", sfp));
2194 if (unlikely(sg_big_buff != def_reserved_size))
2195 sg_big_buff = def_reserved_size;
2197 bufflen = min_t(int, sg_big_buff,
2198 max_sectors_bytes(sdp->device->request_queue));
2199 sg_build_reserve(sfp, bufflen);
2200 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2201 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2202 sfp->reserve.bufflen,
2203 sfp->reserve.k_use_sg));
2205 kref_get(&sdp->d_ref);
2206 __module_get(THIS_MODULE);
2211 sg_remove_sfp_usercontext(struct work_struct *work)
2213 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2214 struct sg_device *sdp = sfp->parentdp;
2216 unsigned long iflags;
2218 /* Cleanup any responses which were never read(). */
2219 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2220 while (!list_empty(&sfp->rq_list)) {
2221 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2222 sg_finish_rem_req(srp);
2223 list_del(&srp->entry);
2224 srp->parentfp = NULL;
2226 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2228 if (sfp->reserve.bufflen > 0) {
2229 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2230 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2231 (int) sfp->reserve.bufflen,
2232 (int) sfp->reserve.k_use_sg));
2233 sg_remove_scat(sfp, &sfp->reserve);
2236 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2237 "sg_remove_sfp: sfp=0x%p\n", sfp));
2240 scsi_device_put(sdp->device);
2241 kref_put(&sdp->d_ref, sg_device_destroy);
2242 module_put(THIS_MODULE);
2246 sg_remove_sfp(struct kref *kref)
2248 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2249 struct sg_device *sdp = sfp->parentdp;
2250 unsigned long iflags;
2252 write_lock_irqsave(&sdp->sfd_lock, iflags);
2253 list_del(&sfp->sfd_siblings);
2254 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2256 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2257 schedule_work(&sfp->ew.work);
2260 #ifdef CONFIG_SCSI_PROC_FS
2262 sg_idr_max_id(int id, void *p, void *data)
2276 unsigned long iflags;
2278 read_lock_irqsave(&sg_index_lock, iflags);
2279 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2280 read_unlock_irqrestore(&sg_index_lock, iflags);
2281 return k + 1; /* origin 1 */
2285 /* must be called with sg_index_lock held */
2286 static Sg_device *sg_lookup_dev(int dev)
2288 return idr_find(&sg_index_idr, dev);
2294 struct sg_device *sdp;
2295 unsigned long flags;
2297 read_lock_irqsave(&sg_index_lock, flags);
2298 sdp = sg_lookup_dev(dev);
2300 sdp = ERR_PTR(-ENXIO);
2301 else if (atomic_read(&sdp->detaching)) {
2302 /* If sdp->detaching, then the refcount may already be 0, in
2303 * which case it would be a bug to do kref_get().
2305 sdp = ERR_PTR(-ENODEV);
2307 kref_get(&sdp->d_ref);
2308 read_unlock_irqrestore(&sg_index_lock, flags);
2313 #ifdef CONFIG_SCSI_PROC_FS
2314 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2316 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2317 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2318 size_t count, loff_t *off);
2319 static const struct file_operations adio_fops = {
2320 .owner = THIS_MODULE,
2321 .open = sg_proc_single_open_adio,
2323 .llseek = seq_lseek,
2324 .write = sg_proc_write_adio,
2325 .release = single_release,
2328 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2329 static ssize_t sg_proc_write_dressz(struct file *filp,
2330 const char __user *buffer, size_t count, loff_t *off);
2331 static const struct file_operations dressz_fops = {
2332 .owner = THIS_MODULE,
2333 .open = sg_proc_single_open_dressz,
2335 .llseek = seq_lseek,
2336 .write = sg_proc_write_dressz,
2337 .release = single_release,
2340 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2341 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2342 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2343 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2344 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2345 static void dev_seq_stop(struct seq_file *s, void *v);
2346 static const struct seq_operations dev_seq_ops = {
2347 .start = dev_seq_start,
2348 .next = dev_seq_next,
2349 .stop = dev_seq_stop,
2350 .show = sg_proc_seq_show_dev,
2353 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2354 static const struct seq_operations devstrs_seq_ops = {
2355 .start = dev_seq_start,
2356 .next = dev_seq_next,
2357 .stop = dev_seq_stop,
2358 .show = sg_proc_seq_show_devstrs,
2361 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2362 static const struct seq_operations debug_seq_ops = {
2363 .start = dev_seq_start,
2364 .next = dev_seq_next,
2365 .stop = dev_seq_stop,
2366 .show = sg_proc_seq_show_debug,
2372 struct proc_dir_entry *p;
2374 p = proc_mkdir("scsi/sg", NULL);
2378 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_fops);
2379 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2380 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_fops);
2381 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2382 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2383 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2384 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2389 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2391 seq_printf(s, "%d\n", *((int *)s->private));
2395 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2397 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2401 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2402 size_t count, loff_t *off)
2407 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2409 err = kstrtoul_from_user(buffer, count, 0, &num);
2412 sg_allow_dio = num ? 1 : 0;
2416 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2418 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2422 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2423 size_t count, loff_t *off)
2426 unsigned long k = ULONG_MAX;
2428 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2431 err = kstrtoul_from_user(buffer, count, 0, &k);
2434 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2441 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2443 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2448 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2450 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2454 struct sg_proc_deviter {
2459 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2461 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2468 it->max = sg_last_dev();
2469 if (it->index >= it->max)
2474 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2476 struct sg_proc_deviter * it = s->private;
2479 return (it->index < it->max) ? it : NULL;
2482 static void dev_seq_stop(struct seq_file *s, void *v)
2487 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2489 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2491 struct scsi_device *scsidp;
2492 unsigned long iflags;
2494 read_lock_irqsave(&sg_index_lock, iflags);
2495 sdp = it ? sg_lookup_dev(it->index) : NULL;
2496 if ((NULL == sdp) || (NULL == sdp->device) ||
2497 (atomic_read(&sdp->detaching)))
2498 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2500 scsidp = sdp->device;
2501 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2502 scsidp->host->host_no, scsidp->channel,
2503 scsidp->id, scsidp->lun, (int) scsidp->type,
2505 (int) scsidp->queue_depth,
2506 (int) atomic_read(&scsidp->device_busy),
2507 (int) scsi_device_online(scsidp));
2509 read_unlock_irqrestore(&sg_index_lock, iflags);
2513 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2515 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2517 struct scsi_device *scsidp;
2518 unsigned long iflags;
2520 read_lock_irqsave(&sg_index_lock, iflags);
2521 sdp = it ? sg_lookup_dev(it->index) : NULL;
2522 scsidp = sdp ? sdp->device : NULL;
2523 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2524 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2525 scsidp->vendor, scsidp->model, scsidp->rev);
2527 seq_puts(s, "<no active device>\n");
2528 read_unlock_irqrestore(&sg_index_lock, iflags);
2532 /* must be called while holding sg_index_lock */
2533 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2535 int k, new_interface, blen, usg;
2538 const sg_io_hdr_t *hp;
2543 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2545 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2546 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2547 "(res)sgat=%d low_dma=%d\n", k,
2548 jiffies_to_msecs(fp->timeout),
2549 fp->reserve.bufflen,
2550 (int) fp->reserve.k_use_sg,
2551 (int) sdp->device->host->unchecked_isa_dma);
2552 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2553 (int) fp->cmd_q, (int) fp->force_packid,
2554 (int) fp->keep_orphan);
2555 list_for_each_entry(srp, &fp->rq_list, entry) {
2557 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2558 if (srp->res_used) {
2559 if (new_interface &&
2560 (SG_FLAG_MMAP_IO & hp->flags))
2565 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2571 blen = srp->data.bufflen;
2572 usg = srp->data.k_use_sg;
2573 seq_puts(s, srp->done ?
2574 ((1 == srp->done) ? "rcv:" : "fin:")
2576 seq_printf(s, " id=%d blen=%d",
2577 srp->header.pack_id, blen);
2579 seq_printf(s, " dur=%d", hp->duration);
2581 ms = jiffies_to_msecs(jiffies);
2582 seq_printf(s, " t_o/elap=%d/%d",
2583 (new_interface ? hp->timeout :
2584 jiffies_to_msecs(fp->timeout)),
2585 (ms > hp->duration ? ms - hp->duration : 0));
2587 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2588 (int) srp->data.cmd_opcode);
2590 if (list_empty(&fp->rq_list))
2591 seq_puts(s, " No requests active\n");
2592 read_unlock(&fp->rq_list_lock);
2596 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2598 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2600 unsigned long iflags;
2602 if (it && (0 == it->index))
2603 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2604 (int)it->max, sg_big_buff);
2606 read_lock_irqsave(&sg_index_lock, iflags);
2607 sdp = it ? sg_lookup_dev(it->index) : NULL;
2610 read_lock(&sdp->sfd_lock);
2611 if (!list_empty(&sdp->sfds)) {
2612 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2613 if (atomic_read(&sdp->detaching))
2614 seq_puts(s, "detaching pending close ");
2615 else if (sdp->device) {
2616 struct scsi_device *scsidp = sdp->device;
2618 seq_printf(s, "%d:%d:%d:%llu em=%d",
2619 scsidp->host->host_no,
2620 scsidp->channel, scsidp->id,
2622 scsidp->host->hostt->emulated);
2624 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2625 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2626 sg_proc_debug_helper(s, sdp);
2628 read_unlock(&sdp->sfd_lock);
2630 read_unlock_irqrestore(&sg_index_lock, iflags);
2634 #endif /* CONFIG_SCSI_PROC_FS */
2636 module_init(init_sg);
2637 module_exit(exit_sg);