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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * History:
4 * Started: Aug 9 by Lawrence Foard ([email protected]),
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 ([email protected]), 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 = srp->header.masked_status ||
867 srp->header.host_status ||
868 srp->header.driver_status;
869 if (srp->done)
870 rinfo[val].duration =
871 srp->header.duration;
872 else {
873 ms = jiffies_to_msecs(jiffies);
874 rinfo[val].duration =
875 (ms > srp->header.duration) ?
876 (ms - srp->header.duration) : 0;
877 }
878 rinfo[val].orphan = srp->orphan;
879 rinfo[val].sg_io_owned = srp->sg_io_owned;
880 rinfo[val].pack_id = srp->header.pack_id;
881 rinfo[val].usr_ptr = srp->header.usr_ptr;
882 val++;
883 }
884}
885
886#ifdef CONFIG_COMPAT
887struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
888 char req_state;
889 char orphan;
890 char sg_io_owned;
891 char problem;
892 int pack_id;
893 compat_uptr_t usr_ptr;
894 unsigned int duration;
895 int unused;
896};
897
898static int put_compat_request_table(struct compat_sg_req_info __user *o,
899 struct sg_req_info *rinfo)
900{
901 int i;
902 for (i = 0; i < SG_MAX_QUEUE; i++) {
903 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
904 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
905 put_user(rinfo[i].duration, &o[i].duration) ||
906 put_user(rinfo[i].unused, &o[i].unused))
907 return -EFAULT;
908 }
909 return 0;
910}
911#endif
912
913static long
914sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
915 unsigned int cmd_in, void __user *p)
916{
917 int __user *ip = p;
918 int result, val, read_only;
919 Sg_request *srp;
920 unsigned long iflags;
921
922 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
923 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
924 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
925
926 switch (cmd_in) {
927 case SG_IO:
928 if (atomic_read(&sdp->detaching))
929 return -ENODEV;
930 if (!scsi_block_when_processing_errors(sdp->device))
931 return -ENXIO;
932 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
933 1, read_only, 1, &srp);
934 if (result < 0)
935 return result;
936 result = wait_event_interruptible(sfp->read_wait,
937 srp_done(sfp, srp));
938 write_lock_irq(&sfp->rq_list_lock);
939 if (srp->done) {
940 srp->done = 2;
941 write_unlock_irq(&sfp->rq_list_lock);
942 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
943 return (result < 0) ? result : 0;
944 }
945 srp->orphan = 1;
946 write_unlock_irq(&sfp->rq_list_lock);
947 return result; /* -ERESTARTSYS because signal hit process */
948 case SG_SET_TIMEOUT:
949 result = get_user(val, ip);
950 if (result)
951 return result;
952 if (val < 0)
953 return -EIO;
954 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
955 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
956 INT_MAX);
957 sfp->timeout_user = val;
958 sfp->timeout = mult_frac(val, HZ, USER_HZ);
959
960 return 0;
961 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
962 /* strange ..., for backward compatibility */
963 return sfp->timeout_user;
964 case SG_SET_FORCE_LOW_DMA:
965 /*
966 * N.B. This ioctl never worked properly, but failed to
967 * return an error value. So returning '0' to keep compability
968 * with legacy applications.
969 */
970 return 0;
971 case SG_GET_LOW_DMA:
972 return put_user(0, ip);
973 case SG_GET_SCSI_ID:
974 {
975 sg_scsi_id_t v;
976
977 if (atomic_read(&sdp->detaching))
978 return -ENODEV;
979 memset(&v, 0, sizeof(v));
980 v.host_no = sdp->device->host->host_no;
981 v.channel = sdp->device->channel;
982 v.scsi_id = sdp->device->id;
983 v.lun = sdp->device->lun;
984 v.scsi_type = sdp->device->type;
985 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
986 v.d_queue_depth = sdp->device->queue_depth;
987 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
988 return -EFAULT;
989 return 0;
990 }
991 case SG_SET_FORCE_PACK_ID:
992 result = get_user(val, ip);
993 if (result)
994 return result;
995 sfp->force_packid = val ? 1 : 0;
996 return 0;
997 case SG_GET_PACK_ID:
998 read_lock_irqsave(&sfp->rq_list_lock, iflags);
999 list_for_each_entry(srp, &sfp->rq_list, entry) {
1000 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1001 read_unlock_irqrestore(&sfp->rq_list_lock,
1002 iflags);
1003 return put_user(srp->header.pack_id, ip);
1004 }
1005 }
1006 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1007 return put_user(-1, ip);
1008 case SG_GET_NUM_WAITING:
1009 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1010 val = 0;
1011 list_for_each_entry(srp, &sfp->rq_list, entry) {
1012 if ((1 == srp->done) && (!srp->sg_io_owned))
1013 ++val;
1014 }
1015 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1016 return put_user(val, ip);
1017 case SG_GET_SG_TABLESIZE:
1018 return put_user(sdp->sg_tablesize, ip);
1019 case SG_SET_RESERVED_SIZE:
1020 result = get_user(val, ip);
1021 if (result)
1022 return result;
1023 if (val < 0)
1024 return -EINVAL;
1025 val = min_t(int, val,
1026 max_sectors_bytes(sdp->device->request_queue));
1027 mutex_lock(&sfp->f_mutex);
1028 if (val != sfp->reserve.bufflen) {
1029 if (sfp->mmap_called ||
1030 sfp->res_in_use) {
1031 mutex_unlock(&sfp->f_mutex);
1032 return -EBUSY;
1033 }
1034
1035 sg_remove_scat(sfp, &sfp->reserve);
1036 sg_build_reserve(sfp, val);
1037 }
1038 mutex_unlock(&sfp->f_mutex);
1039 return 0;
1040 case SG_GET_RESERVED_SIZE:
1041 val = min_t(int, sfp->reserve.bufflen,
1042 max_sectors_bytes(sdp->device->request_queue));
1043 return put_user(val, ip);
1044 case SG_SET_COMMAND_Q:
1045 result = get_user(val, ip);
1046 if (result)
1047 return result;
1048 sfp->cmd_q = val ? 1 : 0;
1049 return 0;
1050 case SG_GET_COMMAND_Q:
1051 return put_user((int) sfp->cmd_q, ip);
1052 case SG_SET_KEEP_ORPHAN:
1053 result = get_user(val, ip);
1054 if (result)
1055 return result;
1056 sfp->keep_orphan = val;
1057 return 0;
1058 case SG_GET_KEEP_ORPHAN:
1059 return put_user((int) sfp->keep_orphan, ip);
1060 case SG_NEXT_CMD_LEN:
1061 result = get_user(val, ip);
1062 if (result)
1063 return result;
1064 if (val > SG_MAX_CDB_SIZE)
1065 return -ENOMEM;
1066 sfp->next_cmd_len = (val > 0) ? val : 0;
1067 return 0;
1068 case SG_GET_VERSION_NUM:
1069 return put_user(sg_version_num, ip);
1070 case SG_GET_ACCESS_COUNT:
1071 /* faked - we don't have a real access count anymore */
1072 val = (sdp->device ? 1 : 0);
1073 return put_user(val, ip);
1074 case SG_GET_REQUEST_TABLE:
1075 {
1076 sg_req_info_t *rinfo;
1077
1078 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1079 GFP_KERNEL);
1080 if (!rinfo)
1081 return -ENOMEM;
1082 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1083 sg_fill_request_table(sfp, rinfo);
1084 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1085 #ifdef CONFIG_COMPAT
1086 if (in_compat_syscall())
1087 result = put_compat_request_table(p, rinfo);
1088 else
1089 #endif
1090 result = copy_to_user(p, rinfo,
1091 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1092 result = result ? -EFAULT : 0;
1093 kfree(rinfo);
1094 return result;
1095 }
1096 case SG_EMULATED_HOST:
1097 if (atomic_read(&sdp->detaching))
1098 return -ENODEV;
1099 return put_user(sdp->device->host->hostt->emulated, ip);
1100 case SCSI_IOCTL_SEND_COMMAND:
1101 if (atomic_read(&sdp->detaching))
1102 return -ENODEV;
1103 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE,
1104 cmd_in, p);
1105 case SG_SET_DEBUG:
1106 result = get_user(val, ip);
1107 if (result)
1108 return result;
1109 sdp->sgdebug = (char) val;
1110 return 0;
1111 case BLKSECTGET:
1112 return put_user(max_sectors_bytes(sdp->device->request_queue),
1113 ip);
1114 case BLKTRACESETUP:
1115 return blk_trace_setup(sdp->device->request_queue, sdp->name,
1116 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1117 NULL, p);
1118 case BLKTRACESTART:
1119 return blk_trace_startstop(sdp->device->request_queue, 1);
1120 case BLKTRACESTOP:
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:
1128 case SG_SCSI_RESET:
1129 if (atomic_read(&sdp->detaching))
1130 return -ENODEV;
1131 break;
1132 default:
1133 if (read_only)
1134 return -EPERM; /* don't know so take safe approach */
1135 break;
1136 }
1137
1138 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1139 cmd_in, filp->f_flags & O_NDELAY);
1140 if (result)
1141 return result;
1142
1143 return -ENOIOCTLCMD;
1144}
1145
1146static long
1147sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1148{
1149 void __user *p = (void __user *)arg;
1150 Sg_device *sdp;
1151 Sg_fd *sfp;
1152 int ret;
1153
1154 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1155 return -ENXIO;
1156
1157 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1158 if (ret != -ENOIOCTLCMD)
1159 return ret;
1160 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE, cmd_in, p);
1161}
1162
1163static __poll_t
1164sg_poll(struct file *filp, poll_table * wait)
1165{
1166 __poll_t res = 0;
1167 Sg_device *sdp;
1168 Sg_fd *sfp;
1169 Sg_request *srp;
1170 int count = 0;
1171 unsigned long iflags;
1172
1173 sfp = filp->private_data;
1174 if (!sfp)
1175 return EPOLLERR;
1176 sdp = sfp->parentdp;
1177 if (!sdp)
1178 return EPOLLERR;
1179 poll_wait(filp, &sfp->read_wait, wait);
1180 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1181 list_for_each_entry(srp, &sfp->rq_list, entry) {
1182 /* if any read waiting, flag it */
1183 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1184 res = EPOLLIN | EPOLLRDNORM;
1185 ++count;
1186 }
1187 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1188
1189 if (atomic_read(&sdp->detaching))
1190 res |= EPOLLHUP;
1191 else if (!sfp->cmd_q) {
1192 if (0 == count)
1193 res |= EPOLLOUT | EPOLLWRNORM;
1194 } else if (count < SG_MAX_QUEUE)
1195 res |= EPOLLOUT | EPOLLWRNORM;
1196 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1197 "sg_poll: res=0x%x\n", (__force u32) res));
1198 return res;
1199}
1200
1201static int
1202sg_fasync(int fd, struct file *filp, int mode)
1203{
1204 Sg_device *sdp;
1205 Sg_fd *sfp;
1206
1207 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1208 return -ENXIO;
1209 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1210 "sg_fasync: mode=%d\n", mode));
1211
1212 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1213}
1214
1215static vm_fault_t
1216sg_vma_fault(struct vm_fault *vmf)
1217{
1218 struct vm_area_struct *vma = vmf->vma;
1219 Sg_fd *sfp;
1220 unsigned long offset, len, sa;
1221 Sg_scatter_hold *rsv_schp;
1222 int k, length;
1223
1224 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1225 return VM_FAULT_SIGBUS;
1226 rsv_schp = &sfp->reserve;
1227 offset = vmf->pgoff << PAGE_SHIFT;
1228 if (offset >= rsv_schp->bufflen)
1229 return VM_FAULT_SIGBUS;
1230 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1231 "sg_vma_fault: offset=%lu, scatg=%d\n",
1232 offset, rsv_schp->k_use_sg));
1233 sa = vma->vm_start;
1234 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1235 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1236 len = vma->vm_end - sa;
1237 len = (len < length) ? len : length;
1238 if (offset < len) {
1239 struct page *page = rsv_schp->pages[k] + (offset >> PAGE_SHIFT);
1240 get_page(page); /* increment page count */
1241 vmf->page = page;
1242 return 0; /* success */
1243 }
1244 sa += len;
1245 offset -= len;
1246 }
1247
1248 return VM_FAULT_SIGBUS;
1249}
1250
1251static const struct vm_operations_struct sg_mmap_vm_ops = {
1252 .fault = sg_vma_fault,
1253};
1254
1255static int
1256sg_mmap(struct file *filp, struct vm_area_struct *vma)
1257{
1258 Sg_fd *sfp;
1259 unsigned long req_sz, len, sa;
1260 Sg_scatter_hold *rsv_schp;
1261 int k, length;
1262 int ret = 0;
1263
1264 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1265 return -ENXIO;
1266 req_sz = vma->vm_end - vma->vm_start;
1267 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1268 "sg_mmap starting, vm_start=%p, len=%d\n",
1269 (void *) vma->vm_start, (int) req_sz));
1270 if (vma->vm_pgoff)
1271 return -EINVAL; /* want no offset */
1272 rsv_schp = &sfp->reserve;
1273 mutex_lock(&sfp->f_mutex);
1274 if (req_sz > rsv_schp->bufflen) {
1275 ret = -ENOMEM; /* cannot map more than reserved buffer */
1276 goto out;
1277 }
1278
1279 sa = vma->vm_start;
1280 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1281 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1282 len = vma->vm_end - sa;
1283 len = (len < length) ? len : length;
1284 sa += len;
1285 }
1286
1287 sfp->mmap_called = 1;
1288 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP);
1289 vma->vm_private_data = sfp;
1290 vma->vm_ops = &sg_mmap_vm_ops;
1291out:
1292 mutex_unlock(&sfp->f_mutex);
1293 return ret;
1294}
1295
1296static void
1297sg_rq_end_io_usercontext(struct work_struct *work)
1298{
1299 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1300 struct sg_fd *sfp = srp->parentfp;
1301
1302 sg_finish_rem_req(srp);
1303 sg_remove_request(sfp, srp);
1304 kref_put(&sfp->f_ref, sg_remove_sfp);
1305}
1306
1307/*
1308 * This function is a "bottom half" handler that is called by the mid
1309 * level when a command is completed (or has failed).
1310 */
1311static enum rq_end_io_ret
1312sg_rq_end_io(struct request *rq, blk_status_t status,
1313 const struct io_comp_batch *iob)
1314{
1315 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
1316 struct sg_request *srp = rq->end_io_data;
1317 Sg_device *sdp;
1318 Sg_fd *sfp;
1319 unsigned long iflags;
1320 unsigned int ms;
1321 char *sense;
1322 int result, resid, done = 1;
1323
1324 if (WARN_ON(srp->done != 0))
1325 return RQ_END_IO_NONE;
1326
1327 sfp = srp->parentfp;
1328 if (WARN_ON(sfp == NULL))
1329 return RQ_END_IO_NONE;
1330
1331 sdp = sfp->parentdp;
1332 if (unlikely(atomic_read(&sdp->detaching)))
1333 pr_info("%s: device detaching\n", __func__);
1334
1335 sense = scmd->sense_buffer;
1336 result = scmd->result;
1337 resid = scmd->resid_len;
1338
1339 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1340 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1341 srp->header.pack_id, result));
1342 srp->header.resid = resid;
1343 if (0 != result) {
1344 struct scsi_sense_hdr sshdr;
1345
1346 srp->header.status = 0xff & result;
1347 srp->header.masked_status = sg_status_byte(result);
1348 srp->header.msg_status = COMMAND_COMPLETE;
1349 srp->header.host_status = host_byte(result);
1350 srp->header.driver_status = driver_byte(result);
1351 if ((sdp->sgdebug > 0) &&
1352 ((CHECK_CONDITION == srp->header.masked_status) ||
1353 (COMMAND_TERMINATED == srp->header.masked_status)))
1354 __scsi_print_sense(sdp->device, __func__, sense,
1355 SCSI_SENSE_BUFFERSIZE);
1356
1357 /* Following if statement is a patch supplied by Eric Youngdale */
1358 if (driver_byte(result) != 0
1359 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1360 && !scsi_sense_is_deferred(&sshdr)
1361 && sshdr.sense_key == UNIT_ATTENTION
1362 && sdp->device->removable) {
1363 /* Detected possible disc change. Set the bit - this */
1364 /* may be used if there are filesystems using this device */
1365 sdp->device->changed = 1;
1366 }
1367 }
1368
1369 if (scmd->sense_len)
1370 memcpy(srp->sense_b, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
1371
1372 /* Rely on write phase to clean out srp status values, so no "else" */
1373
1374 /*
1375 * Free the request as soon as it is complete so that its resources
1376 * can be reused without waiting for userspace to read() the
1377 * result. But keep the associated bio (if any) around until
1378 * blk_rq_unmap_user() can be called from user context.
1379 */
1380 srp->rq = NULL;
1381 blk_mq_free_request(rq);
1382
1383 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1384 if (unlikely(srp->orphan)) {
1385 if (sfp->keep_orphan)
1386 srp->sg_io_owned = 0;
1387 else
1388 done = 0;
1389 }
1390 srp->done = done;
1391 ms = jiffies_to_msecs(jiffies);
1392 srp->header.duration = (ms > srp->header.duration) ?
1393 (ms - srp->header.duration) : 0;
1394 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1395
1396 if (likely(done)) {
1397 /* Now wake up any sg_read() that is waiting for this
1398 * packet.
1399 */
1400 wake_up_interruptible(&sfp->read_wait);
1401 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1402 kref_put(&sfp->f_ref, sg_remove_sfp);
1403 } else {
1404 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1405 schedule_work(&srp->ew.work);
1406 }
1407 return RQ_END_IO_NONE;
1408}
1409
1410static const struct file_operations sg_fops = {
1411 .owner = THIS_MODULE,
1412 .read = sg_read,
1413 .write = sg_write,
1414 .poll = sg_poll,
1415 .unlocked_ioctl = sg_ioctl,
1416 .compat_ioctl = compat_ptr_ioctl,
1417 .open = sg_open,
1418 .mmap = sg_mmap,
1419 .release = sg_release,
1420 .fasync = sg_fasync,
1421};
1422
1423static const struct class sg_sysfs_class = {
1424 .name = "scsi_generic"
1425};
1426
1427static int sg_sysfs_valid = 0;
1428
1429static Sg_device *
1430sg_alloc(struct scsi_device *scsidp)
1431{
1432 struct request_queue *q = scsidp->request_queue;
1433 Sg_device *sdp;
1434 unsigned long iflags;
1435 int error;
1436 u32 k;
1437
1438 sdp = kzalloc_obj(Sg_device);
1439 if (!sdp) {
1440 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1441 "failure\n", __func__);
1442 return ERR_PTR(-ENOMEM);
1443 }
1444
1445 idr_preload(GFP_KERNEL);
1446 write_lock_irqsave(&sg_index_lock, iflags);
1447
1448 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1449 if (error < 0) {
1450 if (error == -ENOSPC) {
1451 sdev_printk(KERN_WARNING, scsidp,
1452 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1453 scsidp->type, SG_MAX_DEVS - 1);
1454 error = -ENODEV;
1455 } else {
1456 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1457 "allocation Sg_device failure: %d\n",
1458 __func__, error);
1459 }
1460 goto out_unlock;
1461 }
1462 k = error;
1463
1464 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1465 "sg_alloc: dev=%d \n", k));
1466 sprintf(sdp->name, "sg%d", k);
1467 sdp->device = scsidp;
1468 mutex_init(&sdp->open_rel_lock);
1469 INIT_LIST_HEAD(&sdp->sfds);
1470 init_waitqueue_head(&sdp->open_wait);
1471 atomic_set(&sdp->detaching, 0);
1472 rwlock_init(&sdp->sfd_lock);
1473 sdp->sg_tablesize = queue_max_segments(q);
1474 sdp->index = k;
1475 kref_init(&sdp->d_ref);
1476 error = 0;
1477
1478out_unlock:
1479 write_unlock_irqrestore(&sg_index_lock, iflags);
1480 idr_preload_end();
1481
1482 if (error) {
1483 kfree(sdp);
1484 return ERR_PTR(error);
1485 }
1486 return sdp;
1487}
1488
1489static int
1490sg_add_device(struct device *cl_dev)
1491{
1492 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1493 Sg_device *sdp = NULL;
1494 struct cdev * cdev = NULL;
1495 int error;
1496 unsigned long iflags;
1497
1498 if (!blk_get_queue(scsidp->request_queue)) {
1499 pr_warn("%s: get scsi_device queue failed\n", __func__);
1500 return -ENODEV;
1501 }
1502
1503 error = -ENOMEM;
1504 cdev = cdev_alloc();
1505 if (!cdev) {
1506 pr_warn("%s: cdev_alloc failed\n", __func__);
1507 goto out;
1508 }
1509 cdev->owner = THIS_MODULE;
1510 cdev->ops = &sg_fops;
1511
1512 sdp = sg_alloc(scsidp);
1513 if (IS_ERR(sdp)) {
1514 pr_warn("%s: sg_alloc failed\n", __func__);
1515 error = PTR_ERR(sdp);
1516 goto out;
1517 }
1518
1519 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1520 if (error)
1521 goto cdev_add_err;
1522
1523 sdp->cdev = cdev;
1524 if (sg_sysfs_valid) {
1525 struct device *sg_class_member;
1526
1527 sg_class_member = device_create(&sg_sysfs_class, cl_dev->parent,
1528 MKDEV(SCSI_GENERIC_MAJOR,
1529 sdp->index),
1530 sdp, "%s", sdp->name);
1531 if (IS_ERR(sg_class_member)) {
1532 pr_err("%s: device_create failed\n", __func__);
1533 error = PTR_ERR(sg_class_member);
1534 goto cdev_add_err;
1535 }
1536 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1537 &sg_class_member->kobj, "generic");
1538 if (error)
1539 pr_err("%s: unable to make symlink 'generic' back "
1540 "to sg%d\n", __func__, sdp->index);
1541 } else
1542 pr_warn("%s: sg_sys Invalid\n", __func__);
1543
1544 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1545 "type %d\n", sdp->index, scsidp->type);
1546
1547 dev_set_drvdata(cl_dev, sdp);
1548
1549 return 0;
1550
1551cdev_add_err:
1552 write_lock_irqsave(&sg_index_lock, iflags);
1553 idr_remove(&sg_index_idr, sdp->index);
1554 write_unlock_irqrestore(&sg_index_lock, iflags);
1555 kfree(sdp);
1556
1557out:
1558 if (cdev)
1559 cdev_del(cdev);
1560 blk_put_queue(scsidp->request_queue);
1561 return error;
1562}
1563
1564static void
1565sg_device_destroy(struct kref *kref)
1566{
1567 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1568 struct request_queue *q = sdp->device->request_queue;
1569 unsigned long flags;
1570
1571 /* CAUTION! Note that the device can still be found via idr_find()
1572 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1573 * any other cleanup.
1574 */
1575
1576 blk_trace_remove(q);
1577 blk_put_queue(q);
1578
1579 write_lock_irqsave(&sg_index_lock, flags);
1580 idr_remove(&sg_index_idr, sdp->index);
1581 write_unlock_irqrestore(&sg_index_lock, flags);
1582
1583 SCSI_LOG_TIMEOUT(3,
1584 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1585
1586 kfree(sdp);
1587}
1588
1589static void
1590sg_remove_device(struct device *cl_dev)
1591{
1592 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1593 Sg_device *sdp = dev_get_drvdata(cl_dev);
1594 unsigned long iflags;
1595 Sg_fd *sfp;
1596 int val;
1597
1598 if (!sdp)
1599 return;
1600 /* want sdp->detaching non-zero as soon as possible */
1601 val = atomic_inc_return(&sdp->detaching);
1602 if (val > 1)
1603 return; /* only want to do following once per device */
1604
1605 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1606 "%s\n", __func__));
1607
1608 read_lock_irqsave(&sdp->sfd_lock, iflags);
1609 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1610 wake_up_interruptible_all(&sfp->read_wait);
1611 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1612 }
1613 wake_up_interruptible_all(&sdp->open_wait);
1614 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1615
1616 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1617 device_destroy(&sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1618 cdev_del(sdp->cdev);
1619 sdp->cdev = NULL;
1620
1621 kref_put(&sdp->d_ref, sg_device_destroy);
1622}
1623
1624module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1625module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1626
1627static int def_reserved_size_set(const char *val, const struct kernel_param *kp)
1628{
1629 int size, ret;
1630
1631 if (!val)
1632 return -EINVAL;
1633
1634 ret = kstrtoint(val, 0, &size);
1635 if (ret)
1636 return ret;
1637
1638 /* limit to 1 MB */
1639 if (size < 0 || size > 1048576)
1640 return -ERANGE;
1641
1642 def_reserved_size = size;
1643 return 0;
1644}
1645
1646static const struct kernel_param_ops def_reserved_size_ops = {
1647 .set = def_reserved_size_set,
1648 .get = param_get_int,
1649};
1650
1651module_param_cb(def_reserved_size, &def_reserved_size_ops, &def_reserved_size,
1652 S_IRUGO | S_IWUSR);
1653
1654MODULE_AUTHOR("Douglas Gilbert");
1655MODULE_DESCRIPTION("SCSI generic (sg) driver");
1656MODULE_LICENSE("GPL");
1657MODULE_VERSION(SG_VERSION_STR);
1658MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1659
1660MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1661 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1662MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1663MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1664
1665static int __init
1666init_sg(void)
1667{
1668 int rc;
1669
1670 if (scatter_elem_sz < PAGE_SIZE) {
1671 scatter_elem_sz = PAGE_SIZE;
1672 scatter_elem_sz_prev = scatter_elem_sz;
1673 }
1674
1675 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1676 SG_MAX_DEVS, "sg");
1677 if (rc)
1678 return rc;
1679 rc = class_register(&sg_sysfs_class);
1680 if (rc)
1681 goto err_out;
1682 sg_sysfs_valid = 1;
1683 rc = scsi_register_interface(&sg_interface);
1684 if (0 == rc) {
1685#ifdef CONFIG_SCSI_PROC_FS
1686 sg_proc_init();
1687#endif /* CONFIG_SCSI_PROC_FS */
1688 return 0;
1689 }
1690 class_unregister(&sg_sysfs_class);
1691err_out:
1692 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1693 return rc;
1694}
1695
1696static void __exit
1697exit_sg(void)
1698{
1699#ifdef CONFIG_SCSI_PROC_FS
1700 remove_proc_subtree("scsi/sg", NULL);
1701#endif /* CONFIG_SCSI_PROC_FS */
1702 scsi_unregister_interface(&sg_interface);
1703 class_unregister(&sg_sysfs_class);
1704 sg_sysfs_valid = 0;
1705 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1706 SG_MAX_DEVS);
1707 idr_destroy(&sg_index_idr);
1708}
1709
1710static int
1711sg_start_req(Sg_request *srp, unsigned char *cmd)
1712{
1713 int res;
1714 struct request *rq;
1715 Sg_fd *sfp = srp->parentfp;
1716 sg_io_hdr_t *hp = &srp->header;
1717 int dxfer_len = (int) hp->dxfer_len;
1718 int dxfer_dir = hp->dxfer_direction;
1719 unsigned int iov_count = hp->iovec_count;
1720 Sg_scatter_hold *req_schp = &srp->data;
1721 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1722 struct request_queue *q = sfp->parentdp->device->request_queue;
1723 struct rq_map_data *md, map_data;
1724 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? ITER_SOURCE : ITER_DEST;
1725 struct scsi_cmnd *scmd;
1726
1727 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1728 "sg_start_req: dxfer_len=%d\n",
1729 dxfer_len));
1730
1731 /*
1732 * NOTE
1733 *
1734 * With scsi-mq enabled, there are a fixed number of preallocated
1735 * requests equal in number to shost->can_queue. If all of the
1736 * preallocated requests are already in use, then scsi_alloc_request()
1737 * will sleep until an active command completes, freeing up a request.
1738 * Although waiting in an asynchronous interface is less than ideal, we
1739 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1740 * not expect an EWOULDBLOCK from this condition.
1741 */
1742 rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1743 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
1744 if (IS_ERR(rq))
1745 return PTR_ERR(rq);
1746 scmd = blk_mq_rq_to_pdu(rq);
1747
1748 if (hp->cmd_len > sizeof(scmd->cmnd)) {
1749 blk_mq_free_request(rq);
1750 return -EINVAL;
1751 }
1752
1753 memcpy(scmd->cmnd, cmd, hp->cmd_len);
1754 scmd->cmd_len = hp->cmd_len;
1755
1756 srp->rq = rq;
1757 rq->end_io_data = srp;
1758 scmd->allowed = SG_DEFAULT_RETRIES;
1759
1760 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1761 return 0;
1762
1763 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1764 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1765 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1766 md = NULL;
1767 else
1768 md = &map_data;
1769
1770 if (md) {
1771 mutex_lock(&sfp->f_mutex);
1772 if (dxfer_len <= rsv_schp->bufflen &&
1773 !sfp->res_in_use) {
1774 sfp->res_in_use = 1;
1775 sg_link_reserve(sfp, srp, dxfer_len);
1776 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1777 res = -EBUSY; /* sfp->res_in_use == 1 */
1778 if (dxfer_len > rsv_schp->bufflen)
1779 res = -ENOMEM;
1780 mutex_unlock(&sfp->f_mutex);
1781 return res;
1782 } else {
1783 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1784 if (res) {
1785 mutex_unlock(&sfp->f_mutex);
1786 return res;
1787 }
1788 }
1789 mutex_unlock(&sfp->f_mutex);
1790
1791 md->pages = req_schp->pages;
1792 md->page_order = req_schp->page_order;
1793 md->nr_entries = req_schp->k_use_sg;
1794 md->offset = 0;
1795 md->null_mapped = hp->dxferp ? 0 : 1;
1796 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1797 md->from_user = 1;
1798 else
1799 md->from_user = 0;
1800 }
1801
1802 res = blk_rq_map_user_io(rq, md, hp->dxferp, hp->dxfer_len,
1803 GFP_KERNEL, iov_count, iov_count, 1, rw);
1804 if (!res) {
1805 srp->bio = rq->bio;
1806
1807 if (!md) {
1808 req_schp->dio_in_use = 1;
1809 hp->info |= SG_INFO_DIRECT_IO;
1810 }
1811 }
1812 return res;
1813}
1814
1815static int
1816sg_finish_rem_req(Sg_request *srp)
1817{
1818 int ret = 0;
1819
1820 Sg_fd *sfp = srp->parentfp;
1821 Sg_scatter_hold *req_schp = &srp->data;
1822
1823 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1824 "sg_finish_rem_req: res_used=%d\n",
1825 (int) srp->res_used));
1826 if (srp->bio)
1827 ret = blk_rq_unmap_user(srp->bio);
1828
1829 if (srp->rq)
1830 blk_mq_free_request(srp->rq);
1831
1832 if (srp->res_used)
1833 sg_unlink_reserve(sfp, srp);
1834 else
1835 sg_remove_scat(sfp, req_schp);
1836
1837 return ret;
1838}
1839
1840static int
1841sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1842{
1843 int sg_bufflen = tablesize * sizeof(struct page *);
1844 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1845
1846 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1847 if (!schp->pages)
1848 return -ENOMEM;
1849 schp->sglist_len = sg_bufflen;
1850 return tablesize; /* number of scat_gath elements allocated */
1851}
1852
1853static int
1854sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1855{
1856 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1857 int sg_tablesize = sfp->parentdp->sg_tablesize;
1858 int blk_size = buff_size, order;
1859 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1860
1861 if (blk_size < 0)
1862 return -EFAULT;
1863 if (0 == blk_size)
1864 ++blk_size; /* don't know why */
1865 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1866 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1867 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1868 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1869 buff_size, blk_size));
1870
1871 /* N.B. ret_sz carried into this block ... */
1872 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1873 if (mx_sc_elems < 0)
1874 return mx_sc_elems; /* most likely -ENOMEM */
1875
1876 num = scatter_elem_sz;
1877 if (unlikely(num != scatter_elem_sz_prev)) {
1878 if (num < PAGE_SIZE) {
1879 scatter_elem_sz = PAGE_SIZE;
1880 scatter_elem_sz_prev = PAGE_SIZE;
1881 } else
1882 scatter_elem_sz_prev = num;
1883 }
1884
1885 order = get_order(num);
1886retry:
1887 ret_sz = 1 << (PAGE_SHIFT + order);
1888
1889 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1890 k++, rem_sz -= ret_sz) {
1891
1892 num = (rem_sz > scatter_elem_sz_prev) ?
1893 scatter_elem_sz_prev : rem_sz;
1894
1895 schp->pages[k] = alloc_pages(gfp_mask, order);
1896 if (!schp->pages[k])
1897 goto out;
1898
1899 if (num == scatter_elem_sz_prev) {
1900 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1901 scatter_elem_sz = ret_sz;
1902 scatter_elem_sz_prev = ret_sz;
1903 }
1904 }
1905
1906 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1907 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1908 k, num, ret_sz));
1909 } /* end of for loop */
1910
1911 schp->page_order = order;
1912 schp->k_use_sg = k;
1913 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1914 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1915 k, rem_sz));
1916
1917 schp->bufflen = blk_size;
1918 if (rem_sz > 0) /* must have failed */
1919 return -ENOMEM;
1920 return 0;
1921out:
1922 for (i = 0; i < k; i++)
1923 __free_pages(schp->pages[i], order);
1924
1925 if (--order >= 0)
1926 goto retry;
1927
1928 return -ENOMEM;
1929}
1930
1931static void
1932sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1933{
1934 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1935 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1936 if (schp->pages && schp->sglist_len > 0) {
1937 if (!schp->dio_in_use) {
1938 int k;
1939
1940 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1941 SCSI_LOG_TIMEOUT(5,
1942 sg_printk(KERN_INFO, sfp->parentdp,
1943 "sg_remove_scat: k=%d, pg=0x%p\n",
1944 k, schp->pages[k]));
1945 __free_pages(schp->pages[k], schp->page_order);
1946 }
1947
1948 kfree(schp->pages);
1949 }
1950 }
1951 memset(schp, 0, sizeof (*schp));
1952}
1953
1954static int
1955sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1956{
1957 Sg_scatter_hold *schp = &srp->data;
1958 int k, num;
1959
1960 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1961 "sg_read_oxfer: num_read_xfer=%d\n",
1962 num_read_xfer));
1963 if ((!outp) || (num_read_xfer <= 0))
1964 return 0;
1965
1966 num = 1 << (PAGE_SHIFT + schp->page_order);
1967 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1968 if (num > num_read_xfer) {
1969 if (copy_to_user(outp, page_address(schp->pages[k]),
1970 num_read_xfer))
1971 return -EFAULT;
1972 break;
1973 } else {
1974 if (copy_to_user(outp, page_address(schp->pages[k]),
1975 num))
1976 return -EFAULT;
1977 num_read_xfer -= num;
1978 if (num_read_xfer <= 0)
1979 break;
1980 outp += num;
1981 }
1982 }
1983
1984 return 0;
1985}
1986
1987static void
1988sg_build_reserve(Sg_fd * sfp, int req_size)
1989{
1990 Sg_scatter_hold *schp = &sfp->reserve;
1991
1992 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1993 "sg_build_reserve: req_size=%d\n", req_size));
1994 do {
1995 if (req_size < PAGE_SIZE)
1996 req_size = PAGE_SIZE;
1997 if (0 == sg_build_indirect(schp, sfp, req_size))
1998 return;
1999 else
2000 sg_remove_scat(sfp, schp);
2001 req_size >>= 1; /* divide by 2 */
2002 } while (req_size > (PAGE_SIZE / 2));
2003}
2004
2005static void
2006sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2007{
2008 Sg_scatter_hold *req_schp = &srp->data;
2009 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2010 int k, num, rem;
2011
2012 srp->res_used = 1;
2013 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2014 "sg_link_reserve: size=%d\n", size));
2015 rem = size;
2016
2017 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2018 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2019 if (rem <= num) {
2020 req_schp->k_use_sg = k + 1;
2021 req_schp->sglist_len = rsv_schp->sglist_len;
2022 req_schp->pages = rsv_schp->pages;
2023
2024 req_schp->bufflen = size;
2025 req_schp->page_order = rsv_schp->page_order;
2026 break;
2027 } else
2028 rem -= num;
2029 }
2030
2031 if (k >= rsv_schp->k_use_sg)
2032 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2033 "sg_link_reserve: BAD size\n"));
2034}
2035
2036static void
2037sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2038{
2039 Sg_scatter_hold *req_schp = &srp->data;
2040
2041 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2042 "sg_unlink_reserve: req->k_use_sg=%d\n",
2043 (int) req_schp->k_use_sg));
2044 req_schp->k_use_sg = 0;
2045 req_schp->bufflen = 0;
2046 req_schp->pages = NULL;
2047 req_schp->page_order = 0;
2048 req_schp->sglist_len = 0;
2049 srp->res_used = 0;
2050 /* Called without mutex lock to avoid deadlock */
2051 sfp->res_in_use = 0;
2052}
2053
2054static Sg_request *
2055sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy)
2056{
2057 Sg_request *resp;
2058 unsigned long iflags;
2059
2060 *busy = false;
2061 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2062 list_for_each_entry(resp, &sfp->rq_list, entry) {
2063 /* look for requests that are not SG_IO owned */
2064 if ((!resp->sg_io_owned) &&
2065 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2066 switch (resp->done) {
2067 case 0: /* request active */
2068 *busy = true;
2069 break;
2070 case 1: /* request done; response ready to return */
2071 resp->done = 2; /* guard against other readers */
2072 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2073 return resp;
2074 case 2: /* response already being returned */
2075 break;
2076 }
2077 }
2078 }
2079 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2080 return NULL;
2081}
2082
2083/* always adds to end of list */
2084static Sg_request *
2085sg_add_request(Sg_fd * sfp)
2086{
2087 int k;
2088 unsigned long iflags;
2089 Sg_request *rp = sfp->req_arr;
2090
2091 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2092 if (!list_empty(&sfp->rq_list)) {
2093 if (!sfp->cmd_q)
2094 goto out_unlock;
2095
2096 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2097 if (!rp->parentfp)
2098 break;
2099 }
2100 if (k >= SG_MAX_QUEUE)
2101 goto out_unlock;
2102 }
2103 memset(rp, 0, sizeof (Sg_request));
2104 rp->parentfp = sfp;
2105 rp->header.duration = jiffies_to_msecs(jiffies);
2106 list_add_tail(&rp->entry, &sfp->rq_list);
2107 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2108 return rp;
2109out_unlock:
2110 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2111 return NULL;
2112}
2113
2114/* Return of 1 for found; 0 for not found */
2115static int
2116sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2117{
2118 unsigned long iflags;
2119 int res = 0;
2120
2121 if (!sfp || !srp || list_empty(&sfp->rq_list))
2122 return res;
2123 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2124 if (!list_empty(&srp->entry)) {
2125 list_del(&srp->entry);
2126 srp->parentfp = NULL;
2127 res = 1;
2128 }
2129 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2130
2131 /*
2132 * If the device is detaching, wakeup any readers in case we just
2133 * removed the last response, which would leave nothing for them to
2134 * return other than -ENODEV.
2135 */
2136 if (unlikely(atomic_read(&sfp->parentdp->detaching)))
2137 wake_up_interruptible_all(&sfp->read_wait);
2138
2139 return res;
2140}
2141
2142static Sg_fd *
2143sg_add_sfp(Sg_device * sdp)
2144{
2145 Sg_fd *sfp;
2146 unsigned long iflags;
2147 int bufflen;
2148
2149 sfp = kzalloc_obj(*sfp, GFP_ATOMIC | __GFP_NOWARN);
2150 if (!sfp)
2151 return ERR_PTR(-ENOMEM);
2152
2153 init_waitqueue_head(&sfp->read_wait);
2154 rwlock_init(&sfp->rq_list_lock);
2155 INIT_LIST_HEAD(&sfp->rq_list);
2156 kref_init(&sfp->f_ref);
2157 mutex_init(&sfp->f_mutex);
2158 sfp->timeout = SG_DEFAULT_TIMEOUT;
2159 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2160 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2161 sfp->cmd_q = SG_DEF_COMMAND_Q;
2162 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2163 sfp->parentdp = sdp;
2164 write_lock_irqsave(&sdp->sfd_lock, iflags);
2165 if (atomic_read(&sdp->detaching)) {
2166 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2167 kfree(sfp);
2168 return ERR_PTR(-ENODEV);
2169 }
2170 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2171 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2172 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2173 "sg_add_sfp: sfp=0x%p\n", sfp));
2174
2175 bufflen = min_t(int, def_reserved_size,
2176 max_sectors_bytes(sdp->device->request_queue));
2177 sg_build_reserve(sfp, bufflen);
2178 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2179 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2180 sfp->reserve.bufflen,
2181 sfp->reserve.k_use_sg));
2182
2183 kref_get(&sdp->d_ref);
2184 __module_get(THIS_MODULE);
2185 return sfp;
2186}
2187
2188static void
2189sg_remove_sfp_usercontext(struct work_struct *work)
2190{
2191 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2192 struct sg_device *sdp = sfp->parentdp;
2193 struct scsi_device *device = sdp->device;
2194 Sg_request *srp;
2195 unsigned long iflags;
2196
2197 /* Cleanup any responses which were never read(). */
2198 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2199 while (!list_empty(&sfp->rq_list)) {
2200 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2201 list_del(&srp->entry);
2202 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2203
2204 sg_finish_rem_req(srp);
2205 /*
2206 * sg_rq_end_io() uses srp->parentfp. Hence, only clear
2207 * srp->parentfp after blk_mq_free_request() has been called.
2208 */
2209 srp->parentfp = NULL;
2210
2211 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2212 }
2213 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2214
2215 if (sfp->reserve.bufflen > 0) {
2216 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2217 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2218 (int) sfp->reserve.bufflen,
2219 (int) sfp->reserve.k_use_sg));
2220 sg_remove_scat(sfp, &sfp->reserve);
2221 }
2222
2223 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2224 "sg_remove_sfp: sfp=0x%p\n", sfp));
2225 kfree(sfp);
2226
2227 kref_put(&sdp->d_ref, sg_device_destroy);
2228 scsi_device_put(device);
2229 module_put(THIS_MODULE);
2230}
2231
2232static void
2233sg_remove_sfp(struct kref *kref)
2234{
2235 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2236 struct sg_device *sdp = sfp->parentdp;
2237 unsigned long iflags;
2238
2239 write_lock_irqsave(&sdp->sfd_lock, iflags);
2240 list_del(&sfp->sfd_siblings);
2241 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2242
2243 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2244 schedule_work(&sfp->ew.work);
2245}
2246
2247#ifdef CONFIG_SCSI_PROC_FS
2248static int
2249sg_idr_max_id(int id, void *p, void *data)
2250{
2251 int *k = data;
2252
2253 if (*k < id)
2254 *k = id;
2255
2256 return 0;
2257}
2258
2259static int
2260sg_last_dev(void)
2261{
2262 int k = -1;
2263 unsigned long iflags;
2264
2265 read_lock_irqsave(&sg_index_lock, iflags);
2266 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2267 read_unlock_irqrestore(&sg_index_lock, iflags);
2268 return k + 1; /* origin 1 */
2269}
2270#endif
2271
2272/* must be called with sg_index_lock held */
2273static Sg_device *sg_lookup_dev(int dev)
2274{
2275 return idr_find(&sg_index_idr, dev);
2276}
2277
2278static Sg_device *
2279sg_get_dev(int dev)
2280{
2281 struct sg_device *sdp;
2282 unsigned long flags;
2283
2284 read_lock_irqsave(&sg_index_lock, flags);
2285 sdp = sg_lookup_dev(dev);
2286 if (!sdp)
2287 sdp = ERR_PTR(-ENXIO);
2288 else if (atomic_read(&sdp->detaching)) {
2289 /* If sdp->detaching, then the refcount may already be 0, in
2290 * which case it would be a bug to do kref_get().
2291 */
2292 sdp = ERR_PTR(-ENODEV);
2293 } else
2294 kref_get(&sdp->d_ref);
2295 read_unlock_irqrestore(&sg_index_lock, flags);
2296
2297 return sdp;
2298}
2299
2300#ifdef CONFIG_SCSI_PROC_FS
2301static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2302
2303static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2304static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2305 size_t count, loff_t *off);
2306static const struct proc_ops adio_proc_ops = {
2307 .proc_open = sg_proc_single_open_adio,
2308 .proc_read = seq_read,
2309 .proc_lseek = seq_lseek,
2310 .proc_write = sg_proc_write_adio,
2311 .proc_release = single_release,
2312};
2313
2314static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2315static ssize_t sg_proc_write_dressz(struct file *filp,
2316 const char __user *buffer, size_t count, loff_t *off);
2317static const struct proc_ops dressz_proc_ops = {
2318 .proc_open = sg_proc_single_open_dressz,
2319 .proc_read = seq_read,
2320 .proc_lseek = seq_lseek,
2321 .proc_write = sg_proc_write_dressz,
2322 .proc_release = single_release,
2323};
2324
2325static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2326static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2327static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2328static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2329static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2330static void dev_seq_stop(struct seq_file *s, void *v);
2331static const struct seq_operations dev_seq_ops = {
2332 .start = dev_seq_start,
2333 .next = dev_seq_next,
2334 .stop = dev_seq_stop,
2335 .show = sg_proc_seq_show_dev,
2336};
2337
2338static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2339static const struct seq_operations devstrs_seq_ops = {
2340 .start = dev_seq_start,
2341 .next = dev_seq_next,
2342 .stop = dev_seq_stop,
2343 .show = sg_proc_seq_show_devstrs,
2344};
2345
2346static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2347static const struct seq_operations debug_seq_ops = {
2348 .start = dev_seq_start,
2349 .next = dev_seq_next,
2350 .stop = dev_seq_stop,
2351 .show = sg_proc_seq_show_debug,
2352};
2353
2354static int
2355sg_proc_init(void)
2356{
2357 struct proc_dir_entry *p;
2358
2359 p = proc_mkdir("scsi/sg", NULL);
2360 if (!p)
2361 return 1;
2362
2363 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);
2364 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2365 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);
2366 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2367 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2368 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2369 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2370 return 0;
2371}
2372
2373
2374static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2375{
2376 seq_printf(s, "%d\n", *((int *)s->private));
2377 return 0;
2378}
2379
2380static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2381{
2382 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2383}
2384
2385static ssize_t
2386sg_proc_write_adio(struct file *filp, const char __user *buffer,
2387 size_t count, loff_t *off)
2388{
2389 int err;
2390 unsigned long num;
2391
2392 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2393 return -EACCES;
2394 err = kstrtoul_from_user(buffer, count, 0, &num);
2395 if (err)
2396 return err;
2397 sg_allow_dio = num ? 1 : 0;
2398 return count;
2399}
2400
2401static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2402{
2403 return single_open(file, sg_proc_seq_show_int, &def_reserved_size);
2404}
2405
2406static ssize_t
2407sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2408 size_t count, loff_t *off)
2409{
2410 int err;
2411 unsigned long k = ULONG_MAX;
2412
2413 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2414 return -EACCES;
2415
2416 err = kstrtoul_from_user(buffer, count, 0, &k);
2417 if (err)
2418 return err;
2419 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2420 def_reserved_size = k;
2421 return count;
2422 }
2423 return -ERANGE;
2424}
2425
2426static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2427{
2428 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2429 sg_version_date);
2430 return 0;
2431}
2432
2433static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2434{
2435 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2436 return 0;
2437}
2438
2439struct sg_proc_deviter {
2440 loff_t index;
2441 size_t max;
2442};
2443
2444static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2445{
2446 struct sg_proc_deviter * it = kmalloc_obj(*it);
2447
2448 s->private = it;
2449 if (! it)
2450 return NULL;
2451
2452 it->index = *pos;
2453 it->max = sg_last_dev();
2454 if (it->index >= it->max)
2455 return NULL;
2456 return it;
2457}
2458
2459static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2460{
2461 struct sg_proc_deviter * it = s->private;
2462
2463 *pos = ++it->index;
2464 return (it->index < it->max) ? it : NULL;
2465}
2466
2467static void dev_seq_stop(struct seq_file *s, void *v)
2468{
2469 kfree(s->private);
2470}
2471
2472static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2473{
2474 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2475 Sg_device *sdp;
2476 struct scsi_device *scsidp;
2477 unsigned long iflags;
2478
2479 read_lock_irqsave(&sg_index_lock, iflags);
2480 sdp = it ? sg_lookup_dev(it->index) : NULL;
2481 if ((NULL == sdp) || (NULL == sdp->device) ||
2482 (atomic_read(&sdp->detaching)))
2483 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2484 else {
2485 scsidp = sdp->device;
2486 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2487 scsidp->host->host_no, scsidp->channel,
2488 scsidp->id, scsidp->lun, (int) scsidp->type,
2489 1,
2490 (int) scsidp->queue_depth,
2491 (int) scsi_device_busy(scsidp),
2492 (int) scsi_device_online(scsidp));
2493 }
2494 read_unlock_irqrestore(&sg_index_lock, iflags);
2495 return 0;
2496}
2497
2498static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2499{
2500 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2501 Sg_device *sdp;
2502 struct scsi_device *scsidp;
2503 unsigned long iflags;
2504
2505 read_lock_irqsave(&sg_index_lock, iflags);
2506 sdp = it ? sg_lookup_dev(it->index) : NULL;
2507 scsidp = sdp ? sdp->device : NULL;
2508 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2509 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2510 scsidp->vendor, scsidp->model, scsidp->rev);
2511 else
2512 seq_puts(s, "<no active device>\n");
2513 read_unlock_irqrestore(&sg_index_lock, iflags);
2514 return 0;
2515}
2516
2517/* must be called while holding sg_index_lock */
2518static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2519{
2520 int k, new_interface, blen, usg;
2521 Sg_request *srp;
2522 Sg_fd *fp;
2523 const sg_io_hdr_t *hp;
2524 const char * cp;
2525 unsigned int ms;
2526 unsigned int duration;
2527
2528 k = 0;
2529 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2530 k++;
2531 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2532 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2533 "(res)sgat=%d low_dma=%d\n", k,
2534 jiffies_to_msecs(fp->timeout),
2535 fp->reserve.bufflen,
2536 (int) fp->reserve.k_use_sg, 0);
2537 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2538 (int) fp->cmd_q, (int) fp->force_packid,
2539 (int) fp->keep_orphan);
2540 list_for_each_entry(srp, &fp->rq_list, entry) {
2541 hp = &srp->header;
2542 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2543 if (srp->res_used) {
2544 if (new_interface &&
2545 (SG_FLAG_MMAP_IO & hp->flags))
2546 cp = " mmap>> ";
2547 else
2548 cp = " rb>> ";
2549 } else {
2550 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2551 cp = " dio>> ";
2552 else
2553 cp = " ";
2554 }
2555 seq_puts(s, cp);
2556 blen = srp->data.bufflen;
2557 usg = srp->data.k_use_sg;
2558 seq_puts(s, srp->done ?
2559 ((1 == srp->done) ? "rcv:" : "fin:")
2560 : "act:");
2561 seq_printf(s, " id=%d blen=%d",
2562 srp->header.pack_id, blen);
2563 if (srp->done)
2564 seq_printf(s, " dur=%u", hp->duration);
2565 else {
2566 ms = jiffies_to_msecs(jiffies);
2567 duration = READ_ONCE(hp->duration);
2568 if (duration)
2569 duration = (ms > duration ?
2570 ms - duration : 0);
2571 seq_printf(s, " t_o/elap=%u/%u",
2572 (new_interface ? hp->timeout :
2573 jiffies_to_msecs(fp->timeout)),
2574 duration);
2575 }
2576 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2577 (int) srp->data.cmd_opcode);
2578 }
2579 if (list_empty(&fp->rq_list))
2580 seq_puts(s, " No requests active\n");
2581 read_unlock(&fp->rq_list_lock);
2582 }
2583}
2584
2585static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2586{
2587 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2588 Sg_device *sdp;
2589 unsigned long iflags;
2590
2591 if (it && (0 == it->index))
2592 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2593 (int)it->max, def_reserved_size);
2594
2595 read_lock_irqsave(&sg_index_lock, iflags);
2596 sdp = it ? sg_lookup_dev(it->index) : NULL;
2597 if (NULL == sdp)
2598 goto skip;
2599 read_lock(&sdp->sfd_lock);
2600 if (!list_empty(&sdp->sfds)) {
2601 seq_printf(s, " >>> device=%s ", sdp->name);
2602 if (atomic_read(&sdp->detaching))
2603 seq_puts(s, "detaching pending close ");
2604 else if (sdp->device) {
2605 struct scsi_device *scsidp = sdp->device;
2606
2607 seq_printf(s, "%d:%d:%d:%llu em=%d",
2608 scsidp->host->host_no,
2609 scsidp->channel, scsidp->id,
2610 scsidp->lun,
2611 scsidp->host->hostt->emulated);
2612 }
2613 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2614 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2615 sg_proc_debug_helper(s, sdp);
2616 }
2617 read_unlock(&sdp->sfd_lock);
2618skip:
2619 read_unlock_irqrestore(&sg_index_lock, iflags);
2620 return 0;
2621}
2622
2623#endif /* CONFIG_SCSI_PROC_FS */
2624
2625module_init(init_sg);
2626module_exit(exit_sg);