Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * History:
4 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
5 * to allow user process control of SCSI devices.
6 * Development Sponsored by Killy Corp. NY NY
7 *
8 * Original driver (sg.c):
9 * Copyright (C) 1992 Lawrence Foard
10 * Version 2 and 3 extensions to driver:
11 * Copyright (C) 1998 - 2014 Douglas Gilbert
12 */
13
14static int sg_version_num = 30536; /* 2 digits for each component */
15#define SG_VERSION_STR "3.5.36"
16
17/*
18 * D. P. Gilbert (dgilbert@interlog.com), notes:
19 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
20 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
21 * (otherwise the macros compile to empty statements).
22 *
23 */
24#include <linux/module.h>
25
26#include <linux/fs.h>
27#include <linux/kernel.h>
28#include <linux/sched.h>
29#include <linux/string.h>
30#include <linux/mm.h>
31#include <linux/errno.h>
32#include <linux/mtio.h>
33#include <linux/ioctl.h>
34#include <linux/major.h>
35#include <linux/slab.h>
36#include <linux/fcntl.h>
37#include <linux/init.h>
38#include <linux/poll.h>
39#include <linux/moduleparam.h>
40#include <linux/cdev.h>
41#include <linux/idr.h>
42#include <linux/seq_file.h>
43#include <linux/blkdev.h>
44#include <linux/delay.h>
45#include <linux/blktrace_api.h>
46#include <linux/mutex.h>
47#include <linux/atomic.h>
48#include <linux/ratelimit.h>
49#include <linux/uio.h>
50#include <linux/cred.h> /* for sg_check_file_access() */
51
52#include <scsi/scsi.h>
53#include <scsi/scsi_cmnd.h>
54#include <scsi/scsi_dbg.h>
55#include <scsi/scsi_device.h>
56#include <scsi/scsi_driver.h>
57#include <scsi/scsi_eh.h>
58#include <scsi/scsi_host.h>
59#include <scsi/scsi_ioctl.h>
60#include <scsi/scsi_tcq.h>
61#include <scsi/sg.h>
62
63#include "scsi_logging.h"
64
65#ifdef CONFIG_SCSI_PROC_FS
66#include <linux/proc_fs.h>
67static char *sg_version_date = "20140603";
68
69static int sg_proc_init(void);
70#endif
71
72#define SG_ALLOW_DIO_DEF 0
73
74#define SG_MAX_DEVS (1 << MINORBITS)
75
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
79 */
80#define SG_MAX_CDB_SIZE 252
81
82#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
83
84/* N.B. This variable is readable and writeable via
85 * /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
86 * of this size (or less if there is not enough memory) will be reserved
87 * for use by this file descriptor.
88 */
89
90/* picks up init parameter */
91static int def_reserved_size = SG_DEF_RESERVED_SIZE;
92static int sg_allow_dio = SG_ALLOW_DIO_DEF;
93
94static int scatter_elem_sz = SG_SCATTER_SZ;
95static int scatter_elem_sz_prev = SG_SCATTER_SZ;
96
97#define SG_SECTOR_SZ 512
98
99static int sg_add_device(struct device *);
100static void sg_remove_device(struct device *);
101
102static DEFINE_IDR(sg_index_idr);
103static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
105
106static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
109};
110
111typedef 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 */
115 struct page **pages;
116 int page_order;
117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
118 unsigned char cmd_opcode; /* first byte of command */
119} Sg_scatter_hold;
120
121struct sg_device; /* forward declarations */
122struct sg_fd;
123
124typedef 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 */
135 struct request *rq;
136 struct bio *bio;
137 struct execute_work ew;
138} Sg_request;
139
140typedef 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 */
158 struct kref f_ref;
159 struct execute_work ew;
160} Sg_fd;
161
162typedef 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 char name[DISK_NAME_LEN];
175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
176 struct kref d_ref;
177} Sg_device;
178
179/* tasklet or soft irq callback */
180static enum rq_end_io_ret sg_rq_end_io(struct request *rq, blk_status_t status,
181 const struct io_comp_batch *iob);
182static int sg_start_req(Sg_request *srp, unsigned char *cmd);
183static int sg_finish_rem_req(Sg_request * srp);
184static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
185static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
186 Sg_request * srp);
187static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
188 const char __user *buf, size_t count, int blocking,
189 int read_only, int sg_io_owned, Sg_request **o_srp);
190static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
191 unsigned char *cmnd, int timeout, int blocking);
192static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
193static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
194static void sg_build_reserve(Sg_fd * sfp, int req_size);
195static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
196static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
197static Sg_fd *sg_add_sfp(Sg_device * sdp);
198static void sg_remove_sfp(struct kref *);
199static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy);
200static Sg_request *sg_add_request(Sg_fd * sfp);
201static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
202static Sg_device *sg_get_dev(int dev);
203static void sg_device_destroy(struct kref *kref);
204
205#define SZ_SG_HEADER sizeof(struct sg_header)
206#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
207#define SZ_SG_IOVEC sizeof(sg_iovec_t)
208#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
209
210#define sg_printk(prefix, sdp, fmt, a...) \
211 sdev_prefix_printk(prefix, (sdp)->device, (sdp)->name, fmt, ##a)
212
213/*
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).
221 *
222 * This function provides protection for the legacy API by restricting the
223 * calling context.
224 */
225static int sg_check_file_access(struct file *filp, const char *caller)
226{
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);
230 return -EPERM;
231 }
232 return 0;
233}
234
235static int sg_allow_access(struct file *filp, unsigned char *cmd)
236{
237 struct sg_fd *sfp = filp->private_data;
238
239 if (sfp->parentdp->device->type == TYPE_SCANNER)
240 return 0;
241 if (!scsi_cmd_allowed(cmd, filp->f_mode & FMODE_WRITE))
242 return -EPERM;
243 return 0;
244}
245
246static int
247open_wait(Sg_device *sdp, int flags)
248{
249 int retval = 0;
250
251 if (flags & O_EXCL) {
252 while (sdp->open_cnt > 0) {
253 mutex_unlock(&sdp->open_rel_lock);
254 retval = wait_event_interruptible(sdp->open_wait,
255 (atomic_read(&sdp->detaching) ||
256 !sdp->open_cnt));
257 mutex_lock(&sdp->open_rel_lock);
258
259 if (retval) /* -ERESTARTSYS */
260 return retval;
261 if (atomic_read(&sdp->detaching))
262 return -ENODEV;
263 }
264 } else {
265 while (sdp->exclude) {
266 mutex_unlock(&sdp->open_rel_lock);
267 retval = wait_event_interruptible(sdp->open_wait,
268 (atomic_read(&sdp->detaching) ||
269 !sdp->exclude));
270 mutex_lock(&sdp->open_rel_lock);
271
272 if (retval) /* -ERESTARTSYS */
273 return retval;
274 if (atomic_read(&sdp->detaching))
275 return -ENODEV;
276 }
277 }
278
279 return retval;
280}
281
282/* Returns 0 on success, else a negated errno value */
283static int
284sg_open(struct inode *inode, struct file *filp)
285{
286 int dev = iminor(inode);
287 int flags = filp->f_flags;
288 struct request_queue *q;
289 struct scsi_device *device;
290 Sg_device *sdp;
291 Sg_fd *sfp;
292 int retval;
293
294 nonseekable_open(inode, filp);
295 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
296 return -EPERM; /* Can't lock it with read only access */
297 sdp = sg_get_dev(dev);
298 if (IS_ERR(sdp))
299 return PTR_ERR(sdp);
300
301 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
302 "sg_open: flags=0x%x\n", flags));
303
304 /* This driver's module count bumped by fops_get in <linux/fs.h> */
305 /* Prevent the device driver from vanishing while we sleep */
306 device = sdp->device;
307 retval = scsi_device_get(device);
308 if (retval)
309 goto sg_put;
310
311 /* scsi_block_when_processing_errors() may block so bypass
312 * check if O_NONBLOCK. Permits SCSI commands to be issued
313 * during error recovery. Tread carefully. */
314 if (!((flags & O_NONBLOCK) ||
315 scsi_block_when_processing_errors(device))) {
316 retval = -ENXIO;
317 /* we are in error recovery for this device */
318 goto sdp_put;
319 }
320
321 mutex_lock(&sdp->open_rel_lock);
322 if (flags & O_NONBLOCK) {
323 if (flags & O_EXCL) {
324 if (sdp->open_cnt > 0) {
325 retval = -EBUSY;
326 goto error_mutex_locked;
327 }
328 } else {
329 if (sdp->exclude) {
330 retval = -EBUSY;
331 goto error_mutex_locked;
332 }
333 }
334 } else {
335 retval = open_wait(sdp, flags);
336 if (retval) /* -ERESTARTSYS or -ENODEV */
337 goto error_mutex_locked;
338 }
339
340 /* N.B. at this point we are holding the open_rel_lock */
341 if (flags & O_EXCL)
342 sdp->exclude = true;
343
344 if (sdp->open_cnt < 1) { /* no existing opens */
345 sdp->sgdebug = 0;
346 q = device->request_queue;
347 sdp->sg_tablesize = queue_max_segments(q);
348 }
349 sfp = sg_add_sfp(sdp);
350 if (IS_ERR(sfp)) {
351 retval = PTR_ERR(sfp);
352 goto out_undo;
353 }
354
355 filp->private_data = sfp;
356 sdp->open_cnt++;
357 mutex_unlock(&sdp->open_rel_lock);
358
359 retval = 0;
360sg_put:
361 kref_put(&sdp->d_ref, sg_device_destroy);
362 return retval;
363
364out_undo:
365 if (flags & O_EXCL) {
366 sdp->exclude = false; /* undo if error */
367 wake_up_interruptible(&sdp->open_wait);
368 }
369error_mutex_locked:
370 mutex_unlock(&sdp->open_rel_lock);
371sdp_put:
372 kref_put(&sdp->d_ref, sg_device_destroy);
373 scsi_device_put(device);
374 return retval;
375}
376
377/* Release resources associated with a successful sg_open()
378 * Returns 0 on success, else a negated errno value */
379static int
380sg_release(struct inode *inode, struct file *filp)
381{
382 Sg_device *sdp;
383 Sg_fd *sfp;
384
385 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
386 return -ENXIO;
387 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
388
389 mutex_lock(&sdp->open_rel_lock);
390 sdp->open_cnt--;
391
392 /* possibly many open()s waiting on exlude clearing, start many;
393 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
394 if (sdp->exclude) {
395 sdp->exclude = false;
396 wake_up_interruptible_all(&sdp->open_wait);
397 } else if (0 == sdp->open_cnt) {
398 wake_up_interruptible(&sdp->open_wait);
399 }
400 mutex_unlock(&sdp->open_rel_lock);
401 kref_put(&sfp->f_ref, sg_remove_sfp);
402 return 0;
403}
404
405static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count)
406{
407 struct sg_header __user *old_hdr = buf;
408 int reply_len;
409
410 if (count >= SZ_SG_HEADER) {
411 /* negative reply_len means v3 format, otherwise v1/v2 */
412 if (get_user(reply_len, &old_hdr->reply_len))
413 return -EFAULT;
414
415 if (reply_len >= 0)
416 return get_user(*pack_id, &old_hdr->pack_id);
417
418 if (in_compat_syscall() &&
419 count >= sizeof(struct compat_sg_io_hdr)) {
420 struct compat_sg_io_hdr __user *hp = buf;
421
422 return get_user(*pack_id, &hp->pack_id);
423 }
424
425 if (count >= sizeof(struct sg_io_hdr)) {
426 struct sg_io_hdr __user *hp = buf;
427
428 return get_user(*pack_id, &hp->pack_id);
429 }
430 }
431
432 /* no valid header was passed, so ignore the pack_id */
433 *pack_id = -1;
434 return 0;
435}
436
437static ssize_t
438sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
439{
440 Sg_device *sdp;
441 Sg_fd *sfp;
442 Sg_request *srp;
443 int req_pack_id = -1;
444 bool busy;
445 sg_io_hdr_t *hp;
446 struct sg_header *old_hdr;
447 int retval;
448
449 /*
450 * This could cause a response to be stranded. Close the associated
451 * file descriptor to free up any resources being held.
452 */
453 retval = sg_check_file_access(filp, __func__);
454 if (retval)
455 return retval;
456
457 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
458 return -ENXIO;
459 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
460 "sg_read: count=%d\n", (int) count));
461
462 if (sfp->force_packid)
463 retval = get_sg_io_pack_id(&req_pack_id, buf, count);
464 if (retval)
465 return retval;
466
467 srp = sg_get_rq_mark(sfp, req_pack_id, &busy);
468 if (!srp) { /* now wait on packet to arrive */
469 if (filp->f_flags & O_NONBLOCK)
470 return -EAGAIN;
471 retval = wait_event_interruptible(sfp->read_wait,
472 ((srp = sg_get_rq_mark(sfp, req_pack_id, &busy)) ||
473 (!busy && atomic_read(&sdp->detaching))));
474 if (!srp)
475 /* signal or detaching */
476 return retval ? retval : -ENODEV;
477 }
478 if (srp->header.interface_id != '\0')
479 return sg_new_read(sfp, buf, count, srp);
480
481 hp = &srp->header;
482 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL);
483 if (!old_hdr)
484 return -ENOMEM;
485
486 old_hdr->reply_len = (int) hp->timeout;
487 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
488 old_hdr->pack_id = hp->pack_id;
489 old_hdr->twelve_byte =
490 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
491 old_hdr->target_status = hp->masked_status;
492 old_hdr->host_status = hp->host_status;
493 old_hdr->driver_status = hp->driver_status;
494 if ((CHECK_CONDITION & hp->masked_status) ||
495 (srp->sense_b[0] & 0x70) == 0x70) {
496 old_hdr->driver_status = DRIVER_SENSE;
497 memcpy(old_hdr->sense_buffer, srp->sense_b,
498 sizeof (old_hdr->sense_buffer));
499 }
500 switch (hp->host_status) {
501 /* This setup of 'result' is for backward compatibility and is best
502 ignored by the user who should use target, host + driver status */
503 case DID_OK:
504 case DID_PASSTHROUGH:
505 case DID_SOFT_ERROR:
506 old_hdr->result = 0;
507 break;
508 case DID_NO_CONNECT:
509 case DID_BUS_BUSY:
510 case DID_TIME_OUT:
511 old_hdr->result = EBUSY;
512 break;
513 case DID_BAD_TARGET:
514 case DID_ABORT:
515 case DID_PARITY:
516 case DID_RESET:
517 case DID_BAD_INTR:
518 old_hdr->result = EIO;
519 break;
520 case DID_ERROR:
521 old_hdr->result = (srp->sense_b[0] == 0 &&
522 hp->masked_status == GOOD) ? 0 : EIO;
523 break;
524 default:
525 old_hdr->result = EIO;
526 break;
527 }
528
529 /* Now copy the result back to the user buffer. */
530 if (count >= SZ_SG_HEADER) {
531 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
532 retval = -EFAULT;
533 goto free_old_hdr;
534 }
535 buf += SZ_SG_HEADER;
536 if (count > old_hdr->reply_len)
537 count = old_hdr->reply_len;
538 if (count > SZ_SG_HEADER) {
539 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
540 retval = -EFAULT;
541 goto free_old_hdr;
542 }
543 }
544 } else
545 count = (old_hdr->result == 0) ? 0 : -EIO;
546 sg_finish_rem_req(srp);
547 sg_remove_request(sfp, srp);
548 retval = count;
549free_old_hdr:
550 kfree(old_hdr);
551 return retval;
552}
553
554static ssize_t
555sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
556{
557 sg_io_hdr_t *hp = &srp->header;
558 int err = 0, err2;
559 int len;
560
561 if (in_compat_syscall()) {
562 if (count < sizeof(struct compat_sg_io_hdr)) {
563 err = -EINVAL;
564 goto err_out;
565 }
566 } else if (count < SZ_SG_IO_HDR) {
567 err = -EINVAL;
568 goto err_out;
569 }
570 hp->sb_len_wr = 0;
571 if ((hp->mx_sb_len > 0) && hp->sbp) {
572 if ((CHECK_CONDITION & hp->masked_status) ||
573 (srp->sense_b[0] & 0x70) == 0x70) {
574 int sb_len = SCSI_SENSE_BUFFERSIZE;
575 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
576 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
577 len = (len > sb_len) ? sb_len : len;
578 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
579 err = -EFAULT;
580 goto err_out;
581 }
582 hp->driver_status = DRIVER_SENSE;
583 hp->sb_len_wr = len;
584 }
585 }
586 if (hp->masked_status || hp->host_status || hp->driver_status)
587 hp->info |= SG_INFO_CHECK;
588 err = put_sg_io_hdr(hp, buf);
589err_out:
590 err2 = sg_finish_rem_req(srp);
591 sg_remove_request(sfp, srp);
592 return err ? : err2 ? : count;
593}
594
595static ssize_t
596sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
597{
598 int mxsize, cmd_size, k;
599 int input_size, blocking;
600 unsigned char opcode;
601 Sg_device *sdp;
602 Sg_fd *sfp;
603 Sg_request *srp;
604 struct sg_header old_hdr;
605 sg_io_hdr_t *hp;
606 unsigned char cmnd[SG_MAX_CDB_SIZE];
607 int retval;
608
609 retval = sg_check_file_access(filp, __func__);
610 if (retval)
611 return retval;
612
613 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
614 return -ENXIO;
615 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
616 "sg_write: count=%d\n", (int) count));
617 if (atomic_read(&sdp->detaching))
618 return -ENODEV;
619 if (!((filp->f_flags & O_NONBLOCK) ||
620 scsi_block_when_processing_errors(sdp->device)))
621 return -ENXIO;
622
623 if (count < SZ_SG_HEADER)
624 return -EIO;
625 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
626 return -EFAULT;
627 blocking = !(filp->f_flags & O_NONBLOCK);
628 if (old_hdr.reply_len < 0)
629 return sg_new_write(sfp, filp, buf, count,
630 blocking, 0, 0, NULL);
631 if (count < (SZ_SG_HEADER + 6))
632 return -EIO; /* The minimum scsi command length is 6 bytes. */
633
634 buf += SZ_SG_HEADER;
635 if (get_user(opcode, buf))
636 return -EFAULT;
637
638 if (!(srp = sg_add_request(sfp))) {
639 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
640 "sg_write: queue full\n"));
641 return -EDOM;
642 }
643 mutex_lock(&sfp->f_mutex);
644 if (sfp->next_cmd_len > 0) {
645 cmd_size = sfp->next_cmd_len;
646 sfp->next_cmd_len = 0; /* reset so only this write() effected */
647 } else {
648 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
649 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
650 cmd_size = 12;
651 }
652 mutex_unlock(&sfp->f_mutex);
653 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
654 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
655/* Determine buffer size. */
656 input_size = count - cmd_size;
657 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
658 mxsize -= SZ_SG_HEADER;
659 input_size -= SZ_SG_HEADER;
660 if (input_size < 0) {
661 sg_remove_request(sfp, srp);
662 return -EIO; /* User did not pass enough bytes for this command. */
663 }
664 hp = &srp->header;
665 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
666 hp->cmd_len = (unsigned char) cmd_size;
667 hp->iovec_count = 0;
668 hp->mx_sb_len = 0;
669 if (input_size > 0)
670 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
671 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
672 else
673 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
674 hp->dxfer_len = mxsize;
675 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
676 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
677 hp->dxferp = (char __user *)buf + cmd_size;
678 else
679 hp->dxferp = NULL;
680 hp->sbp = NULL;
681 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
682 hp->flags = input_size; /* structure abuse ... */
683 hp->pack_id = old_hdr.pack_id;
684 hp->usr_ptr = NULL;
685 if (copy_from_user(cmnd, buf, cmd_size)) {
686 sg_remove_request(sfp, srp);
687 return -EFAULT;
688 }
689 /*
690 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
691 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
692 * is a non-zero input_size, so emit a warning.
693 */
694 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
695 printk_ratelimited(KERN_WARNING
696 "sg_write: data in/out %d/%d bytes "
697 "for SCSI command 0x%x-- guessing "
698 "data in;\n program %s not setting "
699 "count and/or reply_len properly\n",
700 old_hdr.reply_len - (int)SZ_SG_HEADER,
701 input_size, (unsigned int) cmnd[0],
702 current->comm);
703 }
704 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
705 return (k < 0) ? k : count;
706}
707
708static ssize_t
709sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
710 size_t count, int blocking, int read_only, int sg_io_owned,
711 Sg_request **o_srp)
712{
713 int k;
714 Sg_request *srp;
715 sg_io_hdr_t *hp;
716 unsigned char cmnd[SG_MAX_CDB_SIZE];
717 int timeout;
718 unsigned long ul_timeout;
719
720 if (count < SZ_SG_IO_HDR)
721 return -EINVAL;
722
723 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
724 if (!(srp = sg_add_request(sfp))) {
725 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
726 "sg_new_write: queue full\n"));
727 return -EDOM;
728 }
729 srp->sg_io_owned = sg_io_owned;
730 hp = &srp->header;
731 if (get_sg_io_hdr(hp, buf)) {
732 sg_remove_request(sfp, srp);
733 return -EFAULT;
734 }
735 hp->duration = jiffies_to_msecs(jiffies);
736
737 if (hp->interface_id != 'S') {
738 sg_remove_request(sfp, srp);
739 return -ENOSYS;
740 }
741 if (hp->flags & SG_FLAG_MMAP_IO) {
742 if (hp->dxfer_len > sfp->reserve.bufflen) {
743 sg_remove_request(sfp, srp);
744 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
745 }
746 if (hp->flags & SG_FLAG_DIRECT_IO) {
747 sg_remove_request(sfp, srp);
748 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
749 }
750 if (sfp->res_in_use) {
751 sg_remove_request(sfp, srp);
752 return -EBUSY; /* reserve buffer already being used */
753 }
754 }
755 ul_timeout = msecs_to_jiffies(srp->header.timeout);
756 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
757 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
758 sg_remove_request(sfp, srp);
759 return -EMSGSIZE;
760 }
761 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
762 sg_remove_request(sfp, srp);
763 return -EFAULT;
764 }
765 if (read_only && sg_allow_access(file, cmnd)) {
766 sg_remove_request(sfp, srp);
767 return -EPERM;
768 }
769 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
770 if (k < 0)
771 return k;
772 if (o_srp)
773 *o_srp = srp;
774 return count;
775}
776
777static int
778sg_common_write(Sg_fd * sfp, Sg_request * srp,
779 unsigned char *cmnd, int timeout, int blocking)
780{
781 int k, at_head;
782 Sg_device *sdp = sfp->parentdp;
783 sg_io_hdr_t *hp = &srp->header;
784
785 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
786 hp->status = 0;
787 hp->masked_status = 0;
788 hp->msg_status = 0;
789 hp->info = 0;
790 hp->host_status = 0;
791 hp->driver_status = 0;
792 hp->resid = 0;
793 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
794 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
795 (int) cmnd[0], (int) hp->cmd_len));
796
797 if (hp->dxfer_len >= SZ_256M) {
798 sg_remove_request(sfp, srp);
799 return -EINVAL;
800 }
801
802 k = sg_start_req(srp, cmnd);
803 if (k) {
804 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
805 "sg_common_write: start_req err=%d\n", k));
806 sg_finish_rem_req(srp);
807 sg_remove_request(sfp, srp);
808 return k; /* probably out of space --> ENOMEM */
809 }
810 if (atomic_read(&sdp->detaching)) {
811 if (srp->bio) {
812 blk_mq_free_request(srp->rq);
813 srp->rq = NULL;
814 }
815
816 sg_finish_rem_req(srp);
817 sg_remove_request(sfp, srp);
818 return -ENODEV;
819 }
820
821 if (hp->interface_id != '\0' && /* v3 (or later) interface */
822 (SG_FLAG_Q_AT_TAIL & hp->flags))
823 at_head = 0;
824 else
825 at_head = 1;
826
827 srp->rq->timeout = timeout;
828 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
829 srp->rq->end_io = sg_rq_end_io;
830 blk_execute_rq_nowait(srp->rq, at_head);
831 return 0;
832}
833
834static int srp_done(Sg_fd *sfp, Sg_request *srp)
835{
836 unsigned long flags;
837 int ret;
838
839 read_lock_irqsave(&sfp->rq_list_lock, flags);
840 ret = srp->done;
841 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
842 return ret;
843}
844
845static int max_sectors_bytes(struct request_queue *q)
846{
847 unsigned int max_sectors = queue_max_sectors(q);
848
849 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
850
851 return max_sectors << 9;
852}
853
854static void
855sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
856{
857 Sg_request *srp;
858 int val;
859 unsigned int ms;
860
861 val = 0;
862 list_for_each_entry(srp, &sfp->rq_list, entry) {
863 if (val >= SG_MAX_QUEUE)
864 break;
865 rinfo[val].req_state = srp->done + 1;
866 rinfo[val].problem =
867 srp->header.masked_status &
868 srp->header.host_status &
869 srp->header.driver_status;
870 if (srp->done)
871 rinfo[val].duration =
872 srp->header.duration;
873 else {
874 ms = jiffies_to_msecs(jiffies);
875 rinfo[val].duration =
876 (ms > srp->header.duration) ?
877 (ms - srp->header.duration) : 0;
878 }
879 rinfo[val].orphan = srp->orphan;
880 rinfo[val].sg_io_owned = srp->sg_io_owned;
881 rinfo[val].pack_id = srp->header.pack_id;
882 rinfo[val].usr_ptr = srp->header.usr_ptr;
883 val++;
884 }
885}
886
887#ifdef CONFIG_COMPAT
888struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
889 char req_state;
890 char orphan;
891 char sg_io_owned;
892 char problem;
893 int pack_id;
894 compat_uptr_t usr_ptr;
895 unsigned int duration;
896 int unused;
897};
898
899static int put_compat_request_table(struct compat_sg_req_info __user *o,
900 struct sg_req_info *rinfo)
901{
902 int i;
903 for (i = 0; i < SG_MAX_QUEUE; i++) {
904 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
905 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
906 put_user(rinfo[i].duration, &o[i].duration) ||
907 put_user(rinfo[i].unused, &o[i].unused))
908 return -EFAULT;
909 }
910 return 0;
911}
912#endif
913
914static long
915sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
916 unsigned int cmd_in, void __user *p)
917{
918 int __user *ip = p;
919 int result, val, read_only;
920 Sg_request *srp;
921 unsigned long iflags;
922
923 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
924 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
925 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
926
927 switch (cmd_in) {
928 case SG_IO:
929 if (atomic_read(&sdp->detaching))
930 return -ENODEV;
931 if (!scsi_block_when_processing_errors(sdp->device))
932 return -ENXIO;
933 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
934 1, read_only, 1, &srp);
935 if (result < 0)
936 return result;
937 result = wait_event_interruptible(sfp->read_wait,
938 srp_done(sfp, srp));
939 write_lock_irq(&sfp->rq_list_lock);
940 if (srp->done) {
941 srp->done = 2;
942 write_unlock_irq(&sfp->rq_list_lock);
943 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
944 return (result < 0) ? result : 0;
945 }
946 srp->orphan = 1;
947 write_unlock_irq(&sfp->rq_list_lock);
948 return result; /* -ERESTARTSYS because signal hit process */
949 case SG_SET_TIMEOUT:
950 result = get_user(val, ip);
951 if (result)
952 return result;
953 if (val < 0)
954 return -EIO;
955 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
956 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
957 INT_MAX);
958 sfp->timeout_user = val;
959 sfp->timeout = mult_frac(val, HZ, USER_HZ);
960
961 return 0;
962 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
963 /* strange ..., for backward compatibility */
964 return sfp->timeout_user;
965 case SG_SET_FORCE_LOW_DMA:
966 /*
967 * N.B. This ioctl never worked properly, but failed to
968 * return an error value. So returning '0' to keep compability
969 * with legacy applications.
970 */
971 return 0;
972 case SG_GET_LOW_DMA:
973 return put_user(0, ip);
974 case SG_GET_SCSI_ID:
975 {
976 sg_scsi_id_t v;
977
978 if (atomic_read(&sdp->detaching))
979 return -ENODEV;
980 memset(&v, 0, sizeof(v));
981 v.host_no = sdp->device->host->host_no;
982 v.channel = sdp->device->channel;
983 v.scsi_id = sdp->device->id;
984 v.lun = sdp->device->lun;
985 v.scsi_type = sdp->device->type;
986 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
987 v.d_queue_depth = sdp->device->queue_depth;
988 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
989 return -EFAULT;
990 return 0;
991 }
992 case SG_SET_FORCE_PACK_ID:
993 result = get_user(val, ip);
994 if (result)
995 return result;
996 sfp->force_packid = val ? 1 : 0;
997 return 0;
998 case SG_GET_PACK_ID:
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,
1003 iflags);
1004 return put_user(srp->header.pack_id, ip);
1005 }
1006 }
1007 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1008 return put_user(-1, ip);
1009 case SG_GET_NUM_WAITING:
1010 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1011 val = 0;
1012 list_for_each_entry(srp, &sfp->rq_list, entry) {
1013 if ((1 == srp->done) && (!srp->sg_io_owned))
1014 ++val;
1015 }
1016 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1017 return put_user(val, ip);
1018 case SG_GET_SG_TABLESIZE:
1019 return put_user(sdp->sg_tablesize, ip);
1020 case SG_SET_RESERVED_SIZE:
1021 result = get_user(val, ip);
1022 if (result)
1023 return result;
1024 if (val < 0)
1025 return -EINVAL;
1026 val = min_t(int, val,
1027 max_sectors_bytes(sdp->device->request_queue));
1028 mutex_lock(&sfp->f_mutex);
1029 if (val != sfp->reserve.bufflen) {
1030 if (sfp->mmap_called ||
1031 sfp->res_in_use) {
1032 mutex_unlock(&sfp->f_mutex);
1033 return -EBUSY;
1034 }
1035
1036 sg_remove_scat(sfp, &sfp->reserve);
1037 sg_build_reserve(sfp, val);
1038 }
1039 mutex_unlock(&sfp->f_mutex);
1040 return 0;
1041 case SG_GET_RESERVED_SIZE:
1042 val = min_t(int, sfp->reserve.bufflen,
1043 max_sectors_bytes(sdp->device->request_queue));
1044 return put_user(val, ip);
1045 case SG_SET_COMMAND_Q:
1046 result = get_user(val, ip);
1047 if (result)
1048 return result;
1049 sfp->cmd_q = val ? 1 : 0;
1050 return 0;
1051 case SG_GET_COMMAND_Q:
1052 return put_user((int) sfp->cmd_q, ip);
1053 case SG_SET_KEEP_ORPHAN:
1054 result = get_user(val, ip);
1055 if (result)
1056 return result;
1057 sfp->keep_orphan = val;
1058 return 0;
1059 case SG_GET_KEEP_ORPHAN:
1060 return put_user((int) sfp->keep_orphan, ip);
1061 case SG_NEXT_CMD_LEN:
1062 result = get_user(val, ip);
1063 if (result)
1064 return result;
1065 if (val > SG_MAX_CDB_SIZE)
1066 return -ENOMEM;
1067 sfp->next_cmd_len = (val > 0) ? val : 0;
1068 return 0;
1069 case SG_GET_VERSION_NUM:
1070 return put_user(sg_version_num, ip);
1071 case SG_GET_ACCESS_COUNT:
1072 /* faked - we don't have a real access count anymore */
1073 val = (sdp->device ? 1 : 0);
1074 return put_user(val, ip);
1075 case SG_GET_REQUEST_TABLE:
1076 {
1077 sg_req_info_t *rinfo;
1078
1079 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1080 GFP_KERNEL);
1081 if (!rinfo)
1082 return -ENOMEM;
1083 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1084 sg_fill_request_table(sfp, rinfo);
1085 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1086 #ifdef CONFIG_COMPAT
1087 if (in_compat_syscall())
1088 result = put_compat_request_table(p, rinfo);
1089 else
1090 #endif
1091 result = copy_to_user(p, rinfo,
1092 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1093 result = result ? -EFAULT : 0;
1094 kfree(rinfo);
1095 return result;
1096 }
1097 case SG_EMULATED_HOST:
1098 if (atomic_read(&sdp->detaching))
1099 return -ENODEV;
1100 return put_user(sdp->device->host->hostt->emulated, ip);
1101 case SCSI_IOCTL_SEND_COMMAND:
1102 if (atomic_read(&sdp->detaching))
1103 return -ENODEV;
1104 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE,
1105 cmd_in, p);
1106 case SG_SET_DEBUG:
1107 result = get_user(val, ip);
1108 if (result)
1109 return result;
1110 sdp->sgdebug = (char) val;
1111 return 0;
1112 case BLKSECTGET:
1113 return put_user(max_sectors_bytes(sdp->device->request_queue),
1114 ip);
1115 case BLKTRACESETUP:
1116 return blk_trace_setup(sdp->device->request_queue, sdp->name,
1117 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1118 NULL, p);
1119 case BLKTRACESTART:
1120 return blk_trace_startstop(sdp->device->request_queue, 1);
1121 case BLKTRACESTOP:
1122 return blk_trace_startstop(sdp->device->request_queue, 0);
1123 case BLKTRACETEARDOWN:
1124 return blk_trace_remove(sdp->device->request_queue);
1125 case SCSI_IOCTL_GET_IDLUN:
1126 case SCSI_IOCTL_GET_BUS_NUMBER:
1127 case SCSI_IOCTL_PROBE_HOST:
1128 case SG_GET_TRANSFORM:
1129 case SG_SCSI_RESET:
1130 if (atomic_read(&sdp->detaching))
1131 return -ENODEV;
1132 break;
1133 default:
1134 if (read_only)
1135 return -EPERM; /* don't know so take safe approach */
1136 break;
1137 }
1138
1139 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1140 cmd_in, filp->f_flags & O_NDELAY);
1141 if (result)
1142 return result;
1143
1144 return -ENOIOCTLCMD;
1145}
1146
1147static long
1148sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1149{
1150 void __user *p = (void __user *)arg;
1151 Sg_device *sdp;
1152 Sg_fd *sfp;
1153 int ret;
1154
1155 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1156 return -ENXIO;
1157
1158 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1159 if (ret != -ENOIOCTLCMD)
1160 return ret;
1161 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE, cmd_in, p);
1162}
1163
1164static __poll_t
1165sg_poll(struct file *filp, poll_table * wait)
1166{
1167 __poll_t res = 0;
1168 Sg_device *sdp;
1169 Sg_fd *sfp;
1170 Sg_request *srp;
1171 int count = 0;
1172 unsigned long iflags;
1173
1174 sfp = filp->private_data;
1175 if (!sfp)
1176 return EPOLLERR;
1177 sdp = sfp->parentdp;
1178 if (!sdp)
1179 return EPOLLERR;
1180 poll_wait(filp, &sfp->read_wait, wait);
1181 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1182 list_for_each_entry(srp, &sfp->rq_list, entry) {
1183 /* if any read waiting, flag it */
1184 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1185 res = EPOLLIN | EPOLLRDNORM;
1186 ++count;
1187 }
1188 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1189
1190 if (atomic_read(&sdp->detaching))
1191 res |= EPOLLHUP;
1192 else if (!sfp->cmd_q) {
1193 if (0 == count)
1194 res |= EPOLLOUT | EPOLLWRNORM;
1195 } else if (count < SG_MAX_QUEUE)
1196 res |= EPOLLOUT | EPOLLWRNORM;
1197 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1198 "sg_poll: res=0x%x\n", (__force u32) res));
1199 return res;
1200}
1201
1202static int
1203sg_fasync(int fd, struct file *filp, int mode)
1204{
1205 Sg_device *sdp;
1206 Sg_fd *sfp;
1207
1208 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1209 return -ENXIO;
1210 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1211 "sg_fasync: mode=%d\n", mode));
1212
1213 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1214}
1215
1216static vm_fault_t
1217sg_vma_fault(struct vm_fault *vmf)
1218{
1219 struct vm_area_struct *vma = vmf->vma;
1220 Sg_fd *sfp;
1221 unsigned long offset, len, sa;
1222 Sg_scatter_hold *rsv_schp;
1223 int k, length;
1224
1225 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1226 return VM_FAULT_SIGBUS;
1227 rsv_schp = &sfp->reserve;
1228 offset = vmf->pgoff << PAGE_SHIFT;
1229 if (offset >= rsv_schp->bufflen)
1230 return VM_FAULT_SIGBUS;
1231 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1232 "sg_vma_fault: offset=%lu, scatg=%d\n",
1233 offset, rsv_schp->k_use_sg));
1234 sa = vma->vm_start;
1235 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1236 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1237 len = vma->vm_end - sa;
1238 len = (len < length) ? len : length;
1239 if (offset < len) {
1240 struct page *page = rsv_schp->pages[k] + (offset >> PAGE_SHIFT);
1241 get_page(page); /* increment page count */
1242 vmf->page = page;
1243 return 0; /* success */
1244 }
1245 sa += len;
1246 offset -= len;
1247 }
1248
1249 return VM_FAULT_SIGBUS;
1250}
1251
1252static const struct vm_operations_struct sg_mmap_vm_ops = {
1253 .fault = sg_vma_fault,
1254};
1255
1256static int
1257sg_mmap(struct file *filp, struct vm_area_struct *vma)
1258{
1259 Sg_fd *sfp;
1260 unsigned long req_sz, len, sa;
1261 Sg_scatter_hold *rsv_schp;
1262 int k, length;
1263 int ret = 0;
1264
1265 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1266 return -ENXIO;
1267 req_sz = vma->vm_end - vma->vm_start;
1268 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1269 "sg_mmap starting, vm_start=%p, len=%d\n",
1270 (void *) vma->vm_start, (int) req_sz));
1271 if (vma->vm_pgoff)
1272 return -EINVAL; /* want no offset */
1273 rsv_schp = &sfp->reserve;
1274 mutex_lock(&sfp->f_mutex);
1275 if (req_sz > rsv_schp->bufflen) {
1276 ret = -ENOMEM; /* cannot map more than reserved buffer */
1277 goto out;
1278 }
1279
1280 sa = vma->vm_start;
1281 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1282 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1283 len = vma->vm_end - sa;
1284 len = (len < length) ? len : length;
1285 sa += len;
1286 }
1287
1288 sfp->mmap_called = 1;
1289 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP);
1290 vma->vm_private_data = sfp;
1291 vma->vm_ops = &sg_mmap_vm_ops;
1292out:
1293 mutex_unlock(&sfp->f_mutex);
1294 return ret;
1295}
1296
1297static void
1298sg_rq_end_io_usercontext(struct work_struct *work)
1299{
1300 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1301 struct sg_fd *sfp = srp->parentfp;
1302
1303 sg_finish_rem_req(srp);
1304 sg_remove_request(sfp, srp);
1305 kref_put(&sfp->f_ref, sg_remove_sfp);
1306}
1307
1308/*
1309 * This function is a "bottom half" handler that is called by the mid
1310 * level when a command is completed (or has failed).
1311 */
1312static enum rq_end_io_ret
1313sg_rq_end_io(struct request *rq, blk_status_t status,
1314 const struct io_comp_batch *iob)
1315{
1316 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
1317 struct sg_request *srp = rq->end_io_data;
1318 Sg_device *sdp;
1319 Sg_fd *sfp;
1320 unsigned long iflags;
1321 unsigned int ms;
1322 char *sense;
1323 int result, resid, done = 1;
1324
1325 if (WARN_ON(srp->done != 0))
1326 return RQ_END_IO_NONE;
1327
1328 sfp = srp->parentfp;
1329 if (WARN_ON(sfp == NULL))
1330 return RQ_END_IO_NONE;
1331
1332 sdp = sfp->parentdp;
1333 if (unlikely(atomic_read(&sdp->detaching)))
1334 pr_info("%s: device detaching\n", __func__);
1335
1336 sense = scmd->sense_buffer;
1337 result = scmd->result;
1338 resid = scmd->resid_len;
1339
1340 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1341 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1342 srp->header.pack_id, result));
1343 srp->header.resid = resid;
1344 if (0 != result) {
1345 struct scsi_sense_hdr sshdr;
1346
1347 srp->header.status = 0xff & result;
1348 srp->header.masked_status = sg_status_byte(result);
1349 srp->header.msg_status = COMMAND_COMPLETE;
1350 srp->header.host_status = host_byte(result);
1351 srp->header.driver_status = driver_byte(result);
1352 if ((sdp->sgdebug > 0) &&
1353 ((CHECK_CONDITION == srp->header.masked_status) ||
1354 (COMMAND_TERMINATED == srp->header.masked_status)))
1355 __scsi_print_sense(sdp->device, __func__, sense,
1356 SCSI_SENSE_BUFFERSIZE);
1357
1358 /* Following if statement is a patch supplied by Eric Youngdale */
1359 if (driver_byte(result) != 0
1360 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1361 && !scsi_sense_is_deferred(&sshdr)
1362 && sshdr.sense_key == UNIT_ATTENTION
1363 && sdp->device->removable) {
1364 /* Detected possible disc change. Set the bit - this */
1365 /* may be used if there are filesystems using this device */
1366 sdp->device->changed = 1;
1367 }
1368 }
1369
1370 if (scmd->sense_len)
1371 memcpy(srp->sense_b, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
1372
1373 /* Rely on write phase to clean out srp status values, so no "else" */
1374
1375 /*
1376 * Free the request as soon as it is complete so that its resources
1377 * can be reused without waiting for userspace to read() the
1378 * result. But keep the associated bio (if any) around until
1379 * blk_rq_unmap_user() can be called from user context.
1380 */
1381 srp->rq = NULL;
1382 blk_mq_free_request(rq);
1383
1384 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1385 if (unlikely(srp->orphan)) {
1386 if (sfp->keep_orphan)
1387 srp->sg_io_owned = 0;
1388 else
1389 done = 0;
1390 }
1391 srp->done = done;
1392 ms = jiffies_to_msecs(jiffies);
1393 srp->header.duration = (ms > srp->header.duration) ?
1394 (ms - srp->header.duration) : 0;
1395 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1396
1397 if (likely(done)) {
1398 /* Now wake up any sg_read() that is waiting for this
1399 * packet.
1400 */
1401 wake_up_interruptible(&sfp->read_wait);
1402 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1403 kref_put(&sfp->f_ref, sg_remove_sfp);
1404 } else {
1405 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1406 schedule_work(&srp->ew.work);
1407 }
1408 return RQ_END_IO_NONE;
1409}
1410
1411static const struct file_operations sg_fops = {
1412 .owner = THIS_MODULE,
1413 .read = sg_read,
1414 .write = sg_write,
1415 .poll = sg_poll,
1416 .unlocked_ioctl = sg_ioctl,
1417 .compat_ioctl = compat_ptr_ioctl,
1418 .open = sg_open,
1419 .mmap = sg_mmap,
1420 .release = sg_release,
1421 .fasync = sg_fasync,
1422};
1423
1424static const struct class sg_sysfs_class = {
1425 .name = "scsi_generic"
1426};
1427
1428static int sg_sysfs_valid = 0;
1429
1430static Sg_device *
1431sg_alloc(struct scsi_device *scsidp)
1432{
1433 struct request_queue *q = scsidp->request_queue;
1434 Sg_device *sdp;
1435 unsigned long iflags;
1436 int error;
1437 u32 k;
1438
1439 sdp = kzalloc_obj(Sg_device);
1440 if (!sdp) {
1441 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1442 "failure\n", __func__);
1443 return ERR_PTR(-ENOMEM);
1444 }
1445
1446 idr_preload(GFP_KERNEL);
1447 write_lock_irqsave(&sg_index_lock, iflags);
1448
1449 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1450 if (error < 0) {
1451 if (error == -ENOSPC) {
1452 sdev_printk(KERN_WARNING, scsidp,
1453 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1454 scsidp->type, SG_MAX_DEVS - 1);
1455 error = -ENODEV;
1456 } else {
1457 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1458 "allocation Sg_device failure: %d\n",
1459 __func__, error);
1460 }
1461 goto out_unlock;
1462 }
1463 k = error;
1464
1465 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1466 "sg_alloc: dev=%d \n", k));
1467 sprintf(sdp->name, "sg%d", k);
1468 sdp->device = scsidp;
1469 mutex_init(&sdp->open_rel_lock);
1470 INIT_LIST_HEAD(&sdp->sfds);
1471 init_waitqueue_head(&sdp->open_wait);
1472 atomic_set(&sdp->detaching, 0);
1473 rwlock_init(&sdp->sfd_lock);
1474 sdp->sg_tablesize = queue_max_segments(q);
1475 sdp->index = k;
1476 kref_init(&sdp->d_ref);
1477 error = 0;
1478
1479out_unlock:
1480 write_unlock_irqrestore(&sg_index_lock, iflags);
1481 idr_preload_end();
1482
1483 if (error) {
1484 kfree(sdp);
1485 return ERR_PTR(error);
1486 }
1487 return sdp;
1488}
1489
1490static int
1491sg_add_device(struct device *cl_dev)
1492{
1493 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1494 Sg_device *sdp = NULL;
1495 struct cdev * cdev = NULL;
1496 int error;
1497 unsigned long iflags;
1498
1499 if (!blk_get_queue(scsidp->request_queue)) {
1500 pr_warn("%s: get scsi_device queue failed\n", __func__);
1501 return -ENODEV;
1502 }
1503
1504 error = -ENOMEM;
1505 cdev = cdev_alloc();
1506 if (!cdev) {
1507 pr_warn("%s: cdev_alloc failed\n", __func__);
1508 goto out;
1509 }
1510 cdev->owner = THIS_MODULE;
1511 cdev->ops = &sg_fops;
1512
1513 sdp = sg_alloc(scsidp);
1514 if (IS_ERR(sdp)) {
1515 pr_warn("%s: sg_alloc failed\n", __func__);
1516 error = PTR_ERR(sdp);
1517 goto out;
1518 }
1519
1520 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1521 if (error)
1522 goto cdev_add_err;
1523
1524 sdp->cdev = cdev;
1525 if (sg_sysfs_valid) {
1526 struct device *sg_class_member;
1527
1528 sg_class_member = device_create(&sg_sysfs_class, cl_dev->parent,
1529 MKDEV(SCSI_GENERIC_MAJOR,
1530 sdp->index),
1531 sdp, "%s", sdp->name);
1532 if (IS_ERR(sg_class_member)) {
1533 pr_err("%s: device_create failed\n", __func__);
1534 error = PTR_ERR(sg_class_member);
1535 goto cdev_add_err;
1536 }
1537 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1538 &sg_class_member->kobj, "generic");
1539 if (error)
1540 pr_err("%s: unable to make symlink 'generic' back "
1541 "to sg%d\n", __func__, sdp->index);
1542 } else
1543 pr_warn("%s: sg_sys Invalid\n", __func__);
1544
1545 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1546 "type %d\n", sdp->index, scsidp->type);
1547
1548 dev_set_drvdata(cl_dev, sdp);
1549
1550 return 0;
1551
1552cdev_add_err:
1553 write_lock_irqsave(&sg_index_lock, iflags);
1554 idr_remove(&sg_index_idr, sdp->index);
1555 write_unlock_irqrestore(&sg_index_lock, iflags);
1556 kfree(sdp);
1557
1558out:
1559 if (cdev)
1560 cdev_del(cdev);
1561 blk_put_queue(scsidp->request_queue);
1562 return error;
1563}
1564
1565static void
1566sg_device_destroy(struct kref *kref)
1567{
1568 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1569 struct request_queue *q = sdp->device->request_queue;
1570 unsigned long flags;
1571
1572 /* CAUTION! Note that the device can still be found via idr_find()
1573 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1574 * any other cleanup.
1575 */
1576
1577 blk_trace_remove(q);
1578 blk_put_queue(q);
1579
1580 write_lock_irqsave(&sg_index_lock, flags);
1581 idr_remove(&sg_index_idr, sdp->index);
1582 write_unlock_irqrestore(&sg_index_lock, flags);
1583
1584 SCSI_LOG_TIMEOUT(3,
1585 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1586
1587 kfree(sdp);
1588}
1589
1590static void
1591sg_remove_device(struct device *cl_dev)
1592{
1593 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1594 Sg_device *sdp = dev_get_drvdata(cl_dev);
1595 unsigned long iflags;
1596 Sg_fd *sfp;
1597 int val;
1598
1599 if (!sdp)
1600 return;
1601 /* want sdp->detaching non-zero as soon as possible */
1602 val = atomic_inc_return(&sdp->detaching);
1603 if (val > 1)
1604 return; /* only want to do following once per device */
1605
1606 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1607 "%s\n", __func__));
1608
1609 read_lock_irqsave(&sdp->sfd_lock, iflags);
1610 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1611 wake_up_interruptible_all(&sfp->read_wait);
1612 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1613 }
1614 wake_up_interruptible_all(&sdp->open_wait);
1615 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1616
1617 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1618 device_destroy(&sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1619 cdev_del(sdp->cdev);
1620 sdp->cdev = NULL;
1621
1622 kref_put(&sdp->d_ref, sg_device_destroy);
1623}
1624
1625module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1626module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1627
1628static int def_reserved_size_set(const char *val, const struct kernel_param *kp)
1629{
1630 int size, ret;
1631
1632 if (!val)
1633 return -EINVAL;
1634
1635 ret = kstrtoint(val, 0, &size);
1636 if (ret)
1637 return ret;
1638
1639 /* limit to 1 MB */
1640 if (size < 0 || size > 1048576)
1641 return -ERANGE;
1642
1643 def_reserved_size = size;
1644 return 0;
1645}
1646
1647static const struct kernel_param_ops def_reserved_size_ops = {
1648 .set = def_reserved_size_set,
1649 .get = param_get_int,
1650};
1651
1652module_param_cb(def_reserved_size, &def_reserved_size_ops, &def_reserved_size,
1653 S_IRUGO | S_IWUSR);
1654
1655MODULE_AUTHOR("Douglas Gilbert");
1656MODULE_DESCRIPTION("SCSI generic (sg) driver");
1657MODULE_LICENSE("GPL");
1658MODULE_VERSION(SG_VERSION_STR);
1659MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1660
1661MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1662 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1663MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1664MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1665
1666static int __init
1667init_sg(void)
1668{
1669 int rc;
1670
1671 if (scatter_elem_sz < PAGE_SIZE) {
1672 scatter_elem_sz = PAGE_SIZE;
1673 scatter_elem_sz_prev = scatter_elem_sz;
1674 }
1675
1676 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1677 SG_MAX_DEVS, "sg");
1678 if (rc)
1679 return rc;
1680 rc = class_register(&sg_sysfs_class);
1681 if (rc)
1682 goto err_out;
1683 sg_sysfs_valid = 1;
1684 rc = scsi_register_interface(&sg_interface);
1685 if (0 == rc) {
1686#ifdef CONFIG_SCSI_PROC_FS
1687 sg_proc_init();
1688#endif /* CONFIG_SCSI_PROC_FS */
1689 return 0;
1690 }
1691 class_unregister(&sg_sysfs_class);
1692err_out:
1693 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1694 return rc;
1695}
1696
1697static void __exit
1698exit_sg(void)
1699{
1700#ifdef CONFIG_SCSI_PROC_FS
1701 remove_proc_subtree("scsi/sg", NULL);
1702#endif /* CONFIG_SCSI_PROC_FS */
1703 scsi_unregister_interface(&sg_interface);
1704 class_unregister(&sg_sysfs_class);
1705 sg_sysfs_valid = 0;
1706 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1707 SG_MAX_DEVS);
1708 idr_destroy(&sg_index_idr);
1709}
1710
1711static int
1712sg_start_req(Sg_request *srp, unsigned char *cmd)
1713{
1714 int res;
1715 struct request *rq;
1716 Sg_fd *sfp = srp->parentfp;
1717 sg_io_hdr_t *hp = &srp->header;
1718 int dxfer_len = (int) hp->dxfer_len;
1719 int dxfer_dir = hp->dxfer_direction;
1720 unsigned int iov_count = hp->iovec_count;
1721 Sg_scatter_hold *req_schp = &srp->data;
1722 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1723 struct request_queue *q = sfp->parentdp->device->request_queue;
1724 struct rq_map_data *md, map_data;
1725 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? ITER_SOURCE : ITER_DEST;
1726 struct scsi_cmnd *scmd;
1727
1728 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1729 "sg_start_req: dxfer_len=%d\n",
1730 dxfer_len));
1731
1732 /*
1733 * NOTE
1734 *
1735 * With scsi-mq enabled, there are a fixed number of preallocated
1736 * requests equal in number to shost->can_queue. If all of the
1737 * preallocated requests are already in use, then scsi_alloc_request()
1738 * will sleep until an active command completes, freeing up a request.
1739 * Although waiting in an asynchronous interface is less than ideal, we
1740 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1741 * not expect an EWOULDBLOCK from this condition.
1742 */
1743 rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1744 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
1745 if (IS_ERR(rq))
1746 return PTR_ERR(rq);
1747 scmd = blk_mq_rq_to_pdu(rq);
1748
1749 if (hp->cmd_len > sizeof(scmd->cmnd)) {
1750 blk_mq_free_request(rq);
1751 return -EINVAL;
1752 }
1753
1754 memcpy(scmd->cmnd, cmd, hp->cmd_len);
1755 scmd->cmd_len = hp->cmd_len;
1756
1757 srp->rq = rq;
1758 rq->end_io_data = srp;
1759 scmd->allowed = SG_DEFAULT_RETRIES;
1760
1761 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1762 return 0;
1763
1764 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1765 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1766 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1767 md = NULL;
1768 else
1769 md = &map_data;
1770
1771 if (md) {
1772 mutex_lock(&sfp->f_mutex);
1773 if (dxfer_len <= rsv_schp->bufflen &&
1774 !sfp->res_in_use) {
1775 sfp->res_in_use = 1;
1776 sg_link_reserve(sfp, srp, dxfer_len);
1777 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1778 res = -EBUSY; /* sfp->res_in_use == 1 */
1779 if (dxfer_len > rsv_schp->bufflen)
1780 res = -ENOMEM;
1781 mutex_unlock(&sfp->f_mutex);
1782 return res;
1783 } else {
1784 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1785 if (res) {
1786 mutex_unlock(&sfp->f_mutex);
1787 return res;
1788 }
1789 }
1790 mutex_unlock(&sfp->f_mutex);
1791
1792 md->pages = req_schp->pages;
1793 md->page_order = req_schp->page_order;
1794 md->nr_entries = req_schp->k_use_sg;
1795 md->offset = 0;
1796 md->null_mapped = hp->dxferp ? 0 : 1;
1797 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1798 md->from_user = 1;
1799 else
1800 md->from_user = 0;
1801 }
1802
1803 res = blk_rq_map_user_io(rq, md, hp->dxferp, hp->dxfer_len,
1804 GFP_KERNEL, iov_count, iov_count, 1, rw);
1805 if (!res) {
1806 srp->bio = rq->bio;
1807
1808 if (!md) {
1809 req_schp->dio_in_use = 1;
1810 hp->info |= SG_INFO_DIRECT_IO;
1811 }
1812 }
1813 return res;
1814}
1815
1816static int
1817sg_finish_rem_req(Sg_request *srp)
1818{
1819 int ret = 0;
1820
1821 Sg_fd *sfp = srp->parentfp;
1822 Sg_scatter_hold *req_schp = &srp->data;
1823
1824 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1825 "sg_finish_rem_req: res_used=%d\n",
1826 (int) srp->res_used));
1827 if (srp->bio)
1828 ret = blk_rq_unmap_user(srp->bio);
1829
1830 if (srp->rq)
1831 blk_mq_free_request(srp->rq);
1832
1833 if (srp->res_used)
1834 sg_unlink_reserve(sfp, srp);
1835 else
1836 sg_remove_scat(sfp, req_schp);
1837
1838 return ret;
1839}
1840
1841static int
1842sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1843{
1844 int sg_bufflen = tablesize * sizeof(struct page *);
1845 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1846
1847 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1848 if (!schp->pages)
1849 return -ENOMEM;
1850 schp->sglist_len = sg_bufflen;
1851 return tablesize; /* number of scat_gath elements allocated */
1852}
1853
1854static int
1855sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1856{
1857 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1858 int sg_tablesize = sfp->parentdp->sg_tablesize;
1859 int blk_size = buff_size, order;
1860 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1861
1862 if (blk_size < 0)
1863 return -EFAULT;
1864 if (0 == blk_size)
1865 ++blk_size; /* don't know why */
1866 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1867 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1868 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1869 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1870 buff_size, blk_size));
1871
1872 /* N.B. ret_sz carried into this block ... */
1873 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1874 if (mx_sc_elems < 0)
1875 return mx_sc_elems; /* most likely -ENOMEM */
1876
1877 num = scatter_elem_sz;
1878 if (unlikely(num != scatter_elem_sz_prev)) {
1879 if (num < PAGE_SIZE) {
1880 scatter_elem_sz = PAGE_SIZE;
1881 scatter_elem_sz_prev = PAGE_SIZE;
1882 } else
1883 scatter_elem_sz_prev = num;
1884 }
1885
1886 order = get_order(num);
1887retry:
1888 ret_sz = 1 << (PAGE_SHIFT + order);
1889
1890 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1891 k++, rem_sz -= ret_sz) {
1892
1893 num = (rem_sz > scatter_elem_sz_prev) ?
1894 scatter_elem_sz_prev : rem_sz;
1895
1896 schp->pages[k] = alloc_pages(gfp_mask, order);
1897 if (!schp->pages[k])
1898 goto out;
1899
1900 if (num == scatter_elem_sz_prev) {
1901 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1902 scatter_elem_sz = ret_sz;
1903 scatter_elem_sz_prev = ret_sz;
1904 }
1905 }
1906
1907 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1908 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1909 k, num, ret_sz));
1910 } /* end of for loop */
1911
1912 schp->page_order = order;
1913 schp->k_use_sg = k;
1914 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1915 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1916 k, rem_sz));
1917
1918 schp->bufflen = blk_size;
1919 if (rem_sz > 0) /* must have failed */
1920 return -ENOMEM;
1921 return 0;
1922out:
1923 for (i = 0; i < k; i++)
1924 __free_pages(schp->pages[i], order);
1925
1926 if (--order >= 0)
1927 goto retry;
1928
1929 return -ENOMEM;
1930}
1931
1932static void
1933sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1934{
1935 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1936 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1937 if (schp->pages && schp->sglist_len > 0) {
1938 if (!schp->dio_in_use) {
1939 int k;
1940
1941 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1942 SCSI_LOG_TIMEOUT(5,
1943 sg_printk(KERN_INFO, sfp->parentdp,
1944 "sg_remove_scat: k=%d, pg=0x%p\n",
1945 k, schp->pages[k]));
1946 __free_pages(schp->pages[k], schp->page_order);
1947 }
1948
1949 kfree(schp->pages);
1950 }
1951 }
1952 memset(schp, 0, sizeof (*schp));
1953}
1954
1955static int
1956sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1957{
1958 Sg_scatter_hold *schp = &srp->data;
1959 int k, num;
1960
1961 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1962 "sg_read_oxfer: num_read_xfer=%d\n",
1963 num_read_xfer));
1964 if ((!outp) || (num_read_xfer <= 0))
1965 return 0;
1966
1967 num = 1 << (PAGE_SHIFT + schp->page_order);
1968 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1969 if (num > num_read_xfer) {
1970 if (copy_to_user(outp, page_address(schp->pages[k]),
1971 num_read_xfer))
1972 return -EFAULT;
1973 break;
1974 } else {
1975 if (copy_to_user(outp, page_address(schp->pages[k]),
1976 num))
1977 return -EFAULT;
1978 num_read_xfer -= num;
1979 if (num_read_xfer <= 0)
1980 break;
1981 outp += num;
1982 }
1983 }
1984
1985 return 0;
1986}
1987
1988static void
1989sg_build_reserve(Sg_fd * sfp, int req_size)
1990{
1991 Sg_scatter_hold *schp = &sfp->reserve;
1992
1993 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1994 "sg_build_reserve: req_size=%d\n", req_size));
1995 do {
1996 if (req_size < PAGE_SIZE)
1997 req_size = PAGE_SIZE;
1998 if (0 == sg_build_indirect(schp, sfp, req_size))
1999 return;
2000 else
2001 sg_remove_scat(sfp, schp);
2002 req_size >>= 1; /* divide by 2 */
2003 } while (req_size > (PAGE_SIZE / 2));
2004}
2005
2006static void
2007sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2008{
2009 Sg_scatter_hold *req_schp = &srp->data;
2010 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2011 int k, num, rem;
2012
2013 srp->res_used = 1;
2014 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2015 "sg_link_reserve: size=%d\n", size));
2016 rem = size;
2017
2018 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2019 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2020 if (rem <= num) {
2021 req_schp->k_use_sg = k + 1;
2022 req_schp->sglist_len = rsv_schp->sglist_len;
2023 req_schp->pages = rsv_schp->pages;
2024
2025 req_schp->bufflen = size;
2026 req_schp->page_order = rsv_schp->page_order;
2027 break;
2028 } else
2029 rem -= num;
2030 }
2031
2032 if (k >= rsv_schp->k_use_sg)
2033 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2034 "sg_link_reserve: BAD size\n"));
2035}
2036
2037static void
2038sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2039{
2040 Sg_scatter_hold *req_schp = &srp->data;
2041
2042 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2043 "sg_unlink_reserve: req->k_use_sg=%d\n",
2044 (int) req_schp->k_use_sg));
2045 req_schp->k_use_sg = 0;
2046 req_schp->bufflen = 0;
2047 req_schp->pages = NULL;
2048 req_schp->page_order = 0;
2049 req_schp->sglist_len = 0;
2050 srp->res_used = 0;
2051 /* Called without mutex lock to avoid deadlock */
2052 sfp->res_in_use = 0;
2053}
2054
2055static Sg_request *
2056sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy)
2057{
2058 Sg_request *resp;
2059 unsigned long iflags;
2060
2061 *busy = false;
2062 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2063 list_for_each_entry(resp, &sfp->rq_list, entry) {
2064 /* look for requests that are not SG_IO owned */
2065 if ((!resp->sg_io_owned) &&
2066 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2067 switch (resp->done) {
2068 case 0: /* request active */
2069 *busy = true;
2070 break;
2071 case 1: /* request done; response ready to return */
2072 resp->done = 2; /* guard against other readers */
2073 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2074 return resp;
2075 case 2: /* response already being returned */
2076 break;
2077 }
2078 }
2079 }
2080 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2081 return NULL;
2082}
2083
2084/* always adds to end of list */
2085static Sg_request *
2086sg_add_request(Sg_fd * sfp)
2087{
2088 int k;
2089 unsigned long iflags;
2090 Sg_request *rp = sfp->req_arr;
2091
2092 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2093 if (!list_empty(&sfp->rq_list)) {
2094 if (!sfp->cmd_q)
2095 goto out_unlock;
2096
2097 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2098 if (!rp->parentfp)
2099 break;
2100 }
2101 if (k >= SG_MAX_QUEUE)
2102 goto out_unlock;
2103 }
2104 memset(rp, 0, sizeof (Sg_request));
2105 rp->parentfp = sfp;
2106 rp->header.duration = jiffies_to_msecs(jiffies);
2107 list_add_tail(&rp->entry, &sfp->rq_list);
2108 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2109 return rp;
2110out_unlock:
2111 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2112 return NULL;
2113}
2114
2115/* Return of 1 for found; 0 for not found */
2116static int
2117sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2118{
2119 unsigned long iflags;
2120 int res = 0;
2121
2122 if (!sfp || !srp || list_empty(&sfp->rq_list))
2123 return res;
2124 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2125 if (!list_empty(&srp->entry)) {
2126 list_del(&srp->entry);
2127 srp->parentfp = NULL;
2128 res = 1;
2129 }
2130 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2131
2132 /*
2133 * If the device is detaching, wakeup any readers in case we just
2134 * removed the last response, which would leave nothing for them to
2135 * return other than -ENODEV.
2136 */
2137 if (unlikely(atomic_read(&sfp->parentdp->detaching)))
2138 wake_up_interruptible_all(&sfp->read_wait);
2139
2140 return res;
2141}
2142
2143static Sg_fd *
2144sg_add_sfp(Sg_device * sdp)
2145{
2146 Sg_fd *sfp;
2147 unsigned long iflags;
2148 int bufflen;
2149
2150 sfp = kzalloc_obj(*sfp, GFP_ATOMIC | __GFP_NOWARN);
2151 if (!sfp)
2152 return ERR_PTR(-ENOMEM);
2153
2154 init_waitqueue_head(&sfp->read_wait);
2155 rwlock_init(&sfp->rq_list_lock);
2156 INIT_LIST_HEAD(&sfp->rq_list);
2157 kref_init(&sfp->f_ref);
2158 mutex_init(&sfp->f_mutex);
2159 sfp->timeout = SG_DEFAULT_TIMEOUT;
2160 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2161 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2162 sfp->cmd_q = SG_DEF_COMMAND_Q;
2163 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2164 sfp->parentdp = sdp;
2165 write_lock_irqsave(&sdp->sfd_lock, iflags);
2166 if (atomic_read(&sdp->detaching)) {
2167 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2168 kfree(sfp);
2169 return ERR_PTR(-ENODEV);
2170 }
2171 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2172 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2173 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2174 "sg_add_sfp: sfp=0x%p\n", sfp));
2175
2176 bufflen = min_t(int, def_reserved_size,
2177 max_sectors_bytes(sdp->device->request_queue));
2178 sg_build_reserve(sfp, bufflen);
2179 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2180 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2181 sfp->reserve.bufflen,
2182 sfp->reserve.k_use_sg));
2183
2184 kref_get(&sdp->d_ref);
2185 __module_get(THIS_MODULE);
2186 return sfp;
2187}
2188
2189static void
2190sg_remove_sfp_usercontext(struct work_struct *work)
2191{
2192 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2193 struct sg_device *sdp = sfp->parentdp;
2194 struct scsi_device *device = sdp->device;
2195 Sg_request *srp;
2196 unsigned long iflags;
2197
2198 /* Cleanup any responses which were never read(). */
2199 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2200 while (!list_empty(&sfp->rq_list)) {
2201 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2202 list_del(&srp->entry);
2203 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2204
2205 sg_finish_rem_req(srp);
2206 /*
2207 * sg_rq_end_io() uses srp->parentfp. Hence, only clear
2208 * srp->parentfp after blk_mq_free_request() has been called.
2209 */
2210 srp->parentfp = NULL;
2211
2212 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2213 }
2214 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2215
2216 if (sfp->reserve.bufflen > 0) {
2217 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2218 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2219 (int) sfp->reserve.bufflen,
2220 (int) sfp->reserve.k_use_sg));
2221 sg_remove_scat(sfp, &sfp->reserve);
2222 }
2223
2224 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2225 "sg_remove_sfp: sfp=0x%p\n", sfp));
2226 kfree(sfp);
2227
2228 kref_put(&sdp->d_ref, sg_device_destroy);
2229 scsi_device_put(device);
2230 module_put(THIS_MODULE);
2231}
2232
2233static void
2234sg_remove_sfp(struct kref *kref)
2235{
2236 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2237 struct sg_device *sdp = sfp->parentdp;
2238 unsigned long iflags;
2239
2240 write_lock_irqsave(&sdp->sfd_lock, iflags);
2241 list_del(&sfp->sfd_siblings);
2242 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2243
2244 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2245 schedule_work(&sfp->ew.work);
2246}
2247
2248#ifdef CONFIG_SCSI_PROC_FS
2249static int
2250sg_idr_max_id(int id, void *p, void *data)
2251{
2252 int *k = data;
2253
2254 if (*k < id)
2255 *k = id;
2256
2257 return 0;
2258}
2259
2260static int
2261sg_last_dev(void)
2262{
2263 int k = -1;
2264 unsigned long iflags;
2265
2266 read_lock_irqsave(&sg_index_lock, iflags);
2267 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2268 read_unlock_irqrestore(&sg_index_lock, iflags);
2269 return k + 1; /* origin 1 */
2270}
2271#endif
2272
2273/* must be called with sg_index_lock held */
2274static Sg_device *sg_lookup_dev(int dev)
2275{
2276 return idr_find(&sg_index_idr, dev);
2277}
2278
2279static Sg_device *
2280sg_get_dev(int dev)
2281{
2282 struct sg_device *sdp;
2283 unsigned long flags;
2284
2285 read_lock_irqsave(&sg_index_lock, flags);
2286 sdp = sg_lookup_dev(dev);
2287 if (!sdp)
2288 sdp = ERR_PTR(-ENXIO);
2289 else if (atomic_read(&sdp->detaching)) {
2290 /* If sdp->detaching, then the refcount may already be 0, in
2291 * which case it would be a bug to do kref_get().
2292 */
2293 sdp = ERR_PTR(-ENODEV);
2294 } else
2295 kref_get(&sdp->d_ref);
2296 read_unlock_irqrestore(&sg_index_lock, flags);
2297
2298 return sdp;
2299}
2300
2301#ifdef CONFIG_SCSI_PROC_FS
2302static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2303
2304static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2305static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2306 size_t count, loff_t *off);
2307static const struct proc_ops adio_proc_ops = {
2308 .proc_open = sg_proc_single_open_adio,
2309 .proc_read = seq_read,
2310 .proc_lseek = seq_lseek,
2311 .proc_write = sg_proc_write_adio,
2312 .proc_release = single_release,
2313};
2314
2315static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2316static ssize_t sg_proc_write_dressz(struct file *filp,
2317 const char __user *buffer, size_t count, loff_t *off);
2318static const struct proc_ops dressz_proc_ops = {
2319 .proc_open = sg_proc_single_open_dressz,
2320 .proc_read = seq_read,
2321 .proc_lseek = seq_lseek,
2322 .proc_write = sg_proc_write_dressz,
2323 .proc_release = single_release,
2324};
2325
2326static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2327static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2328static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2329static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2330static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2331static void dev_seq_stop(struct seq_file *s, void *v);
2332static const struct seq_operations dev_seq_ops = {
2333 .start = dev_seq_start,
2334 .next = dev_seq_next,
2335 .stop = dev_seq_stop,
2336 .show = sg_proc_seq_show_dev,
2337};
2338
2339static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2340static const struct seq_operations devstrs_seq_ops = {
2341 .start = dev_seq_start,
2342 .next = dev_seq_next,
2343 .stop = dev_seq_stop,
2344 .show = sg_proc_seq_show_devstrs,
2345};
2346
2347static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2348static const struct seq_operations debug_seq_ops = {
2349 .start = dev_seq_start,
2350 .next = dev_seq_next,
2351 .stop = dev_seq_stop,
2352 .show = sg_proc_seq_show_debug,
2353};
2354
2355static int
2356sg_proc_init(void)
2357{
2358 struct proc_dir_entry *p;
2359
2360 p = proc_mkdir("scsi/sg", NULL);
2361 if (!p)
2362 return 1;
2363
2364 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);
2365 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2366 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);
2367 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2368 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2369 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2370 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2371 return 0;
2372}
2373
2374
2375static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2376{
2377 seq_printf(s, "%d\n", *((int *)s->private));
2378 return 0;
2379}
2380
2381static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2382{
2383 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2384}
2385
2386static ssize_t
2387sg_proc_write_adio(struct file *filp, const char __user *buffer,
2388 size_t count, loff_t *off)
2389{
2390 int err;
2391 unsigned long num;
2392
2393 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2394 return -EACCES;
2395 err = kstrtoul_from_user(buffer, count, 0, &num);
2396 if (err)
2397 return err;
2398 sg_allow_dio = num ? 1 : 0;
2399 return count;
2400}
2401
2402static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2403{
2404 return single_open(file, sg_proc_seq_show_int, &def_reserved_size);
2405}
2406
2407static ssize_t
2408sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2409 size_t count, loff_t *off)
2410{
2411 int err;
2412 unsigned long k = ULONG_MAX;
2413
2414 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2415 return -EACCES;
2416
2417 err = kstrtoul_from_user(buffer, count, 0, &k);
2418 if (err)
2419 return err;
2420 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2421 def_reserved_size = k;
2422 return count;
2423 }
2424 return -ERANGE;
2425}
2426
2427static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2428{
2429 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2430 sg_version_date);
2431 return 0;
2432}
2433
2434static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2435{
2436 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2437 return 0;
2438}
2439
2440struct sg_proc_deviter {
2441 loff_t index;
2442 size_t max;
2443};
2444
2445static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2446{
2447 struct sg_proc_deviter * it = kmalloc_obj(*it);
2448
2449 s->private = it;
2450 if (! it)
2451 return NULL;
2452
2453 it->index = *pos;
2454 it->max = sg_last_dev();
2455 if (it->index >= it->max)
2456 return NULL;
2457 return it;
2458}
2459
2460static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2461{
2462 struct sg_proc_deviter * it = s->private;
2463
2464 *pos = ++it->index;
2465 return (it->index < it->max) ? it : NULL;
2466}
2467
2468static void dev_seq_stop(struct seq_file *s, void *v)
2469{
2470 kfree(s->private);
2471}
2472
2473static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2474{
2475 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2476 Sg_device *sdp;
2477 struct scsi_device *scsidp;
2478 unsigned long iflags;
2479
2480 read_lock_irqsave(&sg_index_lock, iflags);
2481 sdp = it ? sg_lookup_dev(it->index) : NULL;
2482 if ((NULL == sdp) || (NULL == sdp->device) ||
2483 (atomic_read(&sdp->detaching)))
2484 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2485 else {
2486 scsidp = sdp->device;
2487 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2488 scsidp->host->host_no, scsidp->channel,
2489 scsidp->id, scsidp->lun, (int) scsidp->type,
2490 1,
2491 (int) scsidp->queue_depth,
2492 (int) scsi_device_busy(scsidp),
2493 (int) scsi_device_online(scsidp));
2494 }
2495 read_unlock_irqrestore(&sg_index_lock, iflags);
2496 return 0;
2497}
2498
2499static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2500{
2501 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2502 Sg_device *sdp;
2503 struct scsi_device *scsidp;
2504 unsigned long iflags;
2505
2506 read_lock_irqsave(&sg_index_lock, iflags);
2507 sdp = it ? sg_lookup_dev(it->index) : NULL;
2508 scsidp = sdp ? sdp->device : NULL;
2509 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2510 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2511 scsidp->vendor, scsidp->model, scsidp->rev);
2512 else
2513 seq_puts(s, "<no active device>\n");
2514 read_unlock_irqrestore(&sg_index_lock, iflags);
2515 return 0;
2516}
2517
2518/* must be called while holding sg_index_lock */
2519static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2520{
2521 int k, new_interface, blen, usg;
2522 Sg_request *srp;
2523 Sg_fd *fp;
2524 const sg_io_hdr_t *hp;
2525 const char * cp;
2526 unsigned int ms;
2527 unsigned int duration;
2528
2529 k = 0;
2530 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2531 k++;
2532 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2533 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2534 "(res)sgat=%d low_dma=%d\n", k,
2535 jiffies_to_msecs(fp->timeout),
2536 fp->reserve.bufflen,
2537 (int) fp->reserve.k_use_sg, 0);
2538 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2539 (int) fp->cmd_q, (int) fp->force_packid,
2540 (int) fp->keep_orphan);
2541 list_for_each_entry(srp, &fp->rq_list, entry) {
2542 hp = &srp->header;
2543 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2544 if (srp->res_used) {
2545 if (new_interface &&
2546 (SG_FLAG_MMAP_IO & hp->flags))
2547 cp = " mmap>> ";
2548 else
2549 cp = " rb>> ";
2550 } else {
2551 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2552 cp = " dio>> ";
2553 else
2554 cp = " ";
2555 }
2556 seq_puts(s, cp);
2557 blen = srp->data.bufflen;
2558 usg = srp->data.k_use_sg;
2559 seq_puts(s, srp->done ?
2560 ((1 == srp->done) ? "rcv:" : "fin:")
2561 : "act:");
2562 seq_printf(s, " id=%d blen=%d",
2563 srp->header.pack_id, blen);
2564 if (srp->done)
2565 seq_printf(s, " dur=%u", hp->duration);
2566 else {
2567 ms = jiffies_to_msecs(jiffies);
2568 duration = READ_ONCE(hp->duration);
2569 if (duration)
2570 duration = (ms > duration ?
2571 ms - duration : 0);
2572 seq_printf(s, " t_o/elap=%u/%u",
2573 (new_interface ? hp->timeout :
2574 jiffies_to_msecs(fp->timeout)),
2575 duration);
2576 }
2577 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2578 (int) srp->data.cmd_opcode);
2579 }
2580 if (list_empty(&fp->rq_list))
2581 seq_puts(s, " No requests active\n");
2582 read_unlock(&fp->rq_list_lock);
2583 }
2584}
2585
2586static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2587{
2588 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2589 Sg_device *sdp;
2590 unsigned long iflags;
2591
2592 if (it && (0 == it->index))
2593 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2594 (int)it->max, def_reserved_size);
2595
2596 read_lock_irqsave(&sg_index_lock, iflags);
2597 sdp = it ? sg_lookup_dev(it->index) : NULL;
2598 if (NULL == sdp)
2599 goto skip;
2600 read_lock(&sdp->sfd_lock);
2601 if (!list_empty(&sdp->sfds)) {
2602 seq_printf(s, " >>> device=%s ", sdp->name);
2603 if (atomic_read(&sdp->detaching))
2604 seq_puts(s, "detaching pending close ");
2605 else if (sdp->device) {
2606 struct scsi_device *scsidp = sdp->device;
2607
2608 seq_printf(s, "%d:%d:%d:%llu em=%d",
2609 scsidp->host->host_no,
2610 scsidp->channel, scsidp->id,
2611 scsidp->lun,
2612 scsidp->host->hostt->emulated);
2613 }
2614 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2615 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2616 sg_proc_debug_helper(s, sdp);
2617 }
2618 read_unlock(&sdp->sfd_lock);
2619skip:
2620 read_unlock_irqrestore(&sg_index_lock, iflags);
2621 return 0;
2622}
2623
2624#endif /* CONFIG_SCSI_PROC_FS */
2625
2626module_init(init_sg);
2627module_exit(exit_sg);