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drm/tests: hdmi: Fix memory leaks in drm_display_mode_from_cea_vic()
[drm/drm-misc.git] / drivers / scsi / sg.c
blobf86be197fedd0420e3bb1ad8f41fc9917d8c13f3
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
14 static 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>
67 static char *sg_version_date = "20140603";
68
69 static 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 static int sg_big_buff = SG_DEF_RESERVED_SIZE;
85 /* N.B. This variable is readable and writeable via
86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
87 of this size (or less if there is not enough memory) will be reserved
88 for use by this file descriptor. [Deprecated usage: this variable is also
89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
90 the kernel (i.e. it is not a module).] */
91 static int def_reserved_size = -1; /* picks up init parameter */
92 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
93
94 static int scatter_elem_sz = SG_SCATTER_SZ;
95 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
96
97 #define SG_SECTOR_SZ 512
98
99 static int sg_add_device(struct device *);
100 static void sg_remove_device(struct device *);
101
102 static DEFINE_IDR(sg_index_idr);
103 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
105
106 static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
109 };
110
111 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
114 unsigned bufflen; /* Size of (aggregate) data buffer */
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
121 struct sg_device; /* forward declarations */
122 struct sg_fd;
123
124 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
125 struct list_head entry; /* list entry */
126 struct sg_fd *parentfp; /* NULL -> not in use */
127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
131 char orphan; /* 1 -> drop on sight, 0 -> normal */
132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
133 /* done protected by rq_list_lock */
134 char done; /* 0->before bh, 1->before read, 2->read */
135 struct request *rq;
136 struct bio *bio;
137 struct execute_work ew;
138 } Sg_request;
139
140 typedef struct sg_fd { /* holds the state of a file descriptor */
141 struct list_head sfd_siblings; /* protected by device's sfd_lock */
142 struct sg_device *parentdp; /* owning device */
143 wait_queue_head_t read_wait; /* queue read until command done */
144 rwlock_t rq_list_lock; /* protect access to list in req_arr */
145 struct mutex f_mutex; /* protect against changes in this fd */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 struct list_head rq_list; /* head of request list */
150 struct fasync_struct *async_qp; /* used by asynchronous notification */
151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
152 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
156 char mmap_called; /* 0 -> mmap() never called on this fd */
157 char res_in_use; /* 1 -> 'reserve' array in use */
158 struct kref f_ref;
159 struct execute_work ew;
160 } Sg_fd;
161
162 typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
165 struct mutex open_rel_lock; /* held when in open() or release() */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 struct list_head sfds;
169 rwlock_t sfd_lock; /* protect access to sfd list */
170 atomic_t detaching; /* 0->device usable, 1->device detaching */
171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174 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 */
180 static enum rq_end_io_ret sg_rq_end_io(struct request *rq, blk_status_t status);
181 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182 static int sg_finish_rem_req(Sg_request * srp);
183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
185 Sg_request * srp);
186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, int sg_io_owned, Sg_request **o_srp);
189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196 static Sg_fd *sg_add_sfp(Sg_device * sdp);
197 static void sg_remove_sfp(struct kref *);
198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy);
199 static Sg_request *sg_add_request(Sg_fd * sfp);
200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201 static Sg_device *sg_get_dev(int dev);
202 static void sg_device_destroy(struct kref *kref);
203
204 #define SZ_SG_HEADER sizeof(struct sg_header)
205 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
206 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
207 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
208
209 #define sg_printk(prefix, sdp, fmt, a...) \
210 sdev_prefix_printk(prefix, (sdp)->device, (sdp)->name, fmt, ##a)
211
212 /*
213 * The SCSI interfaces that use read() and write() as an asynchronous variant of
214 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
215 * to trigger read() and write() calls from various contexts with elevated
216 * privileges. This can lead to kernel memory corruption (e.g. if these
217 * interfaces are called through splice()) and privilege escalation inside
218 * userspace (e.g. if a process with access to such a device passes a file
219 * descriptor to a SUID binary as stdin/stdout/stderr).
220 *
221 * This function provides protection for the legacy API by restricting the
222 * calling context.
223 */
224 static int sg_check_file_access(struct file *filp, const char *caller)
225 {
226 if (filp->f_cred != current_real_cred()) {
227 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
228 caller, task_tgid_vnr(current), current->comm);
229 return -EPERM;
230 }
231 return 0;
232 }
233
234 static int sg_allow_access(struct file *filp, unsigned char *cmd)
235 {
236 struct sg_fd *sfp = filp->private_data;
237
238 if (sfp->parentdp->device->type == TYPE_SCANNER)
239 return 0;
240 if (!scsi_cmd_allowed(cmd, filp->f_mode & FMODE_WRITE))
241 return -EPERM;
242 return 0;
243 }
244
245 static int
246 open_wait(Sg_device *sdp, int flags)
247 {
248 int retval = 0;
249
250 if (flags & O_EXCL) {
251 while (sdp->open_cnt > 0) {
252 mutex_unlock(&sdp->open_rel_lock);
253 retval = wait_event_interruptible(sdp->open_wait,
254 (atomic_read(&sdp->detaching) ||
255 !sdp->open_cnt));
256 mutex_lock(&sdp->open_rel_lock);
257
258 if (retval) /* -ERESTARTSYS */
259 return retval;
260 if (atomic_read(&sdp->detaching))
261 return -ENODEV;
262 }
263 } else {
264 while (sdp->exclude) {
265 mutex_unlock(&sdp->open_rel_lock);
266 retval = wait_event_interruptible(sdp->open_wait,
267 (atomic_read(&sdp->detaching) ||
268 !sdp->exclude));
269 mutex_lock(&sdp->open_rel_lock);
270
271 if (retval) /* -ERESTARTSYS */
272 return retval;
273 if (atomic_read(&sdp->detaching))
274 return -ENODEV;
275 }
276 }
277
278 return retval;
279 }
280
281 /* Returns 0 on success, else a negated errno value */
282 static int
283 sg_open(struct inode *inode, struct file *filp)
284 {
285 int dev = iminor(inode);
286 int flags = filp->f_flags;
287 struct request_queue *q;
288 struct scsi_device *device;
289 Sg_device *sdp;
290 Sg_fd *sfp;
291 int retval;
292
293 nonseekable_open(inode, filp);
294 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
295 return -EPERM; /* Can't lock it with read only access */
296 sdp = sg_get_dev(dev);
297 if (IS_ERR(sdp))
298 return PTR_ERR(sdp);
299
300 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
301 "sg_open: flags=0x%x\n", flags));
302
303 /* This driver's module count bumped by fops_get in <linux/fs.h> */
304 /* Prevent the device driver from vanishing while we sleep */
305 device = sdp->device;
306 retval = scsi_device_get(device);
307 if (retval)
308 goto sg_put;
309
310 retval = scsi_autopm_get_device(device);
311 if (retval)
312 goto sdp_put;
313
314 /* scsi_block_when_processing_errors() may block so bypass
315 * check if O_NONBLOCK. Permits SCSI commands to be issued
316 * during error recovery. Tread carefully. */
317 if (!((flags & O_NONBLOCK) ||
318 scsi_block_when_processing_errors(device))) {
319 retval = -ENXIO;
320 /* we are in error recovery for this device */
321 goto error_out;
322 }
323
324 mutex_lock(&sdp->open_rel_lock);
325 if (flags & O_NONBLOCK) {
326 if (flags & O_EXCL) {
327 if (sdp->open_cnt > 0) {
328 retval = -EBUSY;
329 goto error_mutex_locked;
330 }
331 } else {
332 if (sdp->exclude) {
333 retval = -EBUSY;
334 goto error_mutex_locked;
335 }
336 }
337 } else {
338 retval = open_wait(sdp, flags);
339 if (retval) /* -ERESTARTSYS or -ENODEV */
340 goto error_mutex_locked;
341 }
342
343 /* N.B. at this point we are holding the open_rel_lock */
344 if (flags & O_EXCL)
345 sdp->exclude = true;
346
347 if (sdp->open_cnt < 1) { /* no existing opens */
348 sdp->sgdebug = 0;
349 q = device->request_queue;
350 sdp->sg_tablesize = queue_max_segments(q);
351 }
352 sfp = sg_add_sfp(sdp);
353 if (IS_ERR(sfp)) {
354 retval = PTR_ERR(sfp);
355 goto out_undo;
356 }
357
358 filp->private_data = sfp;
359 sdp->open_cnt++;
360 mutex_unlock(&sdp->open_rel_lock);
361
362 retval = 0;
363 sg_put:
364 kref_put(&sdp->d_ref, sg_device_destroy);
365 return retval;
366
367 out_undo:
368 if (flags & O_EXCL) {
369 sdp->exclude = false; /* undo if error */
370 wake_up_interruptible(&sdp->open_wait);
371 }
372 error_mutex_locked:
373 mutex_unlock(&sdp->open_rel_lock);
374 error_out:
375 scsi_autopm_put_device(device);
376 sdp_put:
377 kref_put(&sdp->d_ref, sg_device_destroy);
378 scsi_device_put(device);
379 return retval;
380 }
381
382 /* Release resources associated with a successful sg_open()
383 * Returns 0 on success, else a negated errno value */
384 static int
385 sg_release(struct inode *inode, struct file *filp)
386 {
387 Sg_device *sdp;
388 Sg_fd *sfp;
389
390 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
391 return -ENXIO;
392 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
393
394 mutex_lock(&sdp->open_rel_lock);
395 scsi_autopm_put_device(sdp->device);
396 kref_put(&sfp->f_ref, sg_remove_sfp);
397 sdp->open_cnt--;
398
399 /* possibly many open()s waiting on exlude clearing, start many;
400 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
401 if (sdp->exclude) {
402 sdp->exclude = false;
403 wake_up_interruptible_all(&sdp->open_wait);
404 } else if (0 == sdp->open_cnt) {
405 wake_up_interruptible(&sdp->open_wait);
406 }
407 mutex_unlock(&sdp->open_rel_lock);
408 return 0;
409 }
410
411 static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count)
412 {
413 struct sg_header __user *old_hdr = buf;
414 int reply_len;
415
416 if (count >= SZ_SG_HEADER) {
417 /* negative reply_len means v3 format, otherwise v1/v2 */
418 if (get_user(reply_len, &old_hdr->reply_len))
419 return -EFAULT;
420
421 if (reply_len >= 0)
422 return get_user(*pack_id, &old_hdr->pack_id);
423
424 if (in_compat_syscall() &&
425 count >= sizeof(struct compat_sg_io_hdr)) {
426 struct compat_sg_io_hdr __user *hp = buf;
427
428 return get_user(*pack_id, &hp->pack_id);
429 }
430
431 if (count >= sizeof(struct sg_io_hdr)) {
432 struct sg_io_hdr __user *hp = buf;
433
434 return get_user(*pack_id, &hp->pack_id);
435 }
436 }
437
438 /* no valid header was passed, so ignore the pack_id */
439 *pack_id = -1;
440 return 0;
441 }
442
443 static ssize_t
444 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
445 {
446 Sg_device *sdp;
447 Sg_fd *sfp;
448 Sg_request *srp;
449 int req_pack_id = -1;
450 bool busy;
451 sg_io_hdr_t *hp;
452 struct sg_header *old_hdr;
453 int retval;
454
455 /*
456 * This could cause a response to be stranded. Close the associated
457 * file descriptor to free up any resources being held.
458 */
459 retval = sg_check_file_access(filp, __func__);
460 if (retval)
461 return retval;
462
463 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
464 return -ENXIO;
465 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
466 "sg_read: count=%d\n", (int) count));
467
468 if (sfp->force_packid)
469 retval = get_sg_io_pack_id(&req_pack_id, buf, count);
470 if (retval)
471 return retval;
472
473 srp = sg_get_rq_mark(sfp, req_pack_id, &busy);
474 if (!srp) { /* now wait on packet to arrive */
475 if (filp->f_flags & O_NONBLOCK)
476 return -EAGAIN;
477 retval = wait_event_interruptible(sfp->read_wait,
478 ((srp = sg_get_rq_mark(sfp, req_pack_id, &busy)) ||
479 (!busy && atomic_read(&sdp->detaching))));
480 if (!srp)
481 /* signal or detaching */
482 return retval ? retval : -ENODEV;
483 }
484 if (srp->header.interface_id != '\0')
485 return sg_new_read(sfp, buf, count, srp);
486
487 hp = &srp->header;
488 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL);
489 if (!old_hdr)
490 return -ENOMEM;
491
492 old_hdr->reply_len = (int) hp->timeout;
493 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
494 old_hdr->pack_id = hp->pack_id;
495 old_hdr->twelve_byte =
496 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
497 old_hdr->target_status = hp->masked_status;
498 old_hdr->host_status = hp->host_status;
499 old_hdr->driver_status = hp->driver_status;
500 if ((CHECK_CONDITION & hp->masked_status) ||
501 (srp->sense_b[0] & 0x70) == 0x70) {
502 old_hdr->driver_status = DRIVER_SENSE;
503 memcpy(old_hdr->sense_buffer, srp->sense_b,
504 sizeof (old_hdr->sense_buffer));
505 }
506 switch (hp->host_status) {
507 /* This setup of 'result' is for backward compatibility and is best
508 ignored by the user who should use target, host + driver status */
509 case DID_OK:
510 case DID_PASSTHROUGH:
511 case DID_SOFT_ERROR:
512 old_hdr->result = 0;
513 break;
514 case DID_NO_CONNECT:
515 case DID_BUS_BUSY:
516 case DID_TIME_OUT:
517 old_hdr->result = EBUSY;
518 break;
519 case DID_BAD_TARGET:
520 case DID_ABORT:
521 case DID_PARITY:
522 case DID_RESET:
523 case DID_BAD_INTR:
524 old_hdr->result = EIO;
525 break;
526 case DID_ERROR:
527 old_hdr->result = (srp->sense_b[0] == 0 &&
528 hp->masked_status == GOOD) ? 0 : EIO;
529 break;
530 default:
531 old_hdr->result = EIO;
532 break;
533 }
534
535 /* Now copy the result back to the user buffer. */
536 if (count >= SZ_SG_HEADER) {
537 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
538 retval = -EFAULT;
539 goto free_old_hdr;
540 }
541 buf += SZ_SG_HEADER;
542 if (count > old_hdr->reply_len)
543 count = old_hdr->reply_len;
544 if (count > SZ_SG_HEADER) {
545 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
546 retval = -EFAULT;
547 goto free_old_hdr;
548 }
549 }
550 } else
551 count = (old_hdr->result == 0) ? 0 : -EIO;
552 sg_finish_rem_req(srp);
553 sg_remove_request(sfp, srp);
554 retval = count;
555 free_old_hdr:
556 kfree(old_hdr);
557 return retval;
558 }
559
560 static ssize_t
561 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
562 {
563 sg_io_hdr_t *hp = &srp->header;
564 int err = 0, err2;
565 int len;
566
567 if (in_compat_syscall()) {
568 if (count < sizeof(struct compat_sg_io_hdr)) {
569 err = -EINVAL;
570 goto err_out;
571 }
572 } else if (count < SZ_SG_IO_HDR) {
573 err = -EINVAL;
574 goto err_out;
575 }
576 hp->sb_len_wr = 0;
577 if ((hp->mx_sb_len > 0) && hp->sbp) {
578 if ((CHECK_CONDITION & hp->masked_status) ||
579 (srp->sense_b[0] & 0x70) == 0x70) {
580 int sb_len = SCSI_SENSE_BUFFERSIZE;
581 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
582 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
583 len = (len > sb_len) ? sb_len : len;
584 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
585 err = -EFAULT;
586 goto err_out;
587 }
588 hp->driver_status = DRIVER_SENSE;
589 hp->sb_len_wr = len;
590 }
591 }
592 if (hp->masked_status || hp->host_status || hp->driver_status)
593 hp->info |= SG_INFO_CHECK;
594 err = put_sg_io_hdr(hp, buf);
595 err_out:
596 err2 = sg_finish_rem_req(srp);
597 sg_remove_request(sfp, srp);
598 return err ? : err2 ? : count;
599 }
600
601 static ssize_t
602 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
603 {
604 int mxsize, cmd_size, k;
605 int input_size, blocking;
606 unsigned char opcode;
607 Sg_device *sdp;
608 Sg_fd *sfp;
609 Sg_request *srp;
610 struct sg_header old_hdr;
611 sg_io_hdr_t *hp;
612 unsigned char cmnd[SG_MAX_CDB_SIZE];
613 int retval;
614
615 retval = sg_check_file_access(filp, __func__);
616 if (retval)
617 return retval;
618
619 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
620 return -ENXIO;
621 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
622 "sg_write: count=%d\n", (int) count));
623 if (atomic_read(&sdp->detaching))
624 return -ENODEV;
625 if (!((filp->f_flags & O_NONBLOCK) ||
626 scsi_block_when_processing_errors(sdp->device)))
627 return -ENXIO;
628
629 if (count < SZ_SG_HEADER)
630 return -EIO;
631 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
632 return -EFAULT;
633 blocking = !(filp->f_flags & O_NONBLOCK);
634 if (old_hdr.reply_len < 0)
635 return sg_new_write(sfp, filp, buf, count,
636 blocking, 0, 0, NULL);
637 if (count < (SZ_SG_HEADER + 6))
638 return -EIO; /* The minimum scsi command length is 6 bytes. */
639
640 buf += SZ_SG_HEADER;
641 if (get_user(opcode, buf))
642 return -EFAULT;
643
644 if (!(srp = sg_add_request(sfp))) {
645 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
646 "sg_write: queue full\n"));
647 return -EDOM;
648 }
649 mutex_lock(&sfp->f_mutex);
650 if (sfp->next_cmd_len > 0) {
651 cmd_size = sfp->next_cmd_len;
652 sfp->next_cmd_len = 0; /* reset so only this write() effected */
653 } else {
654 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
655 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
656 cmd_size = 12;
657 }
658 mutex_unlock(&sfp->f_mutex);
659 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
660 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
661 /* Determine buffer size. */
662 input_size = count - cmd_size;
663 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
664 mxsize -= SZ_SG_HEADER;
665 input_size -= SZ_SG_HEADER;
666 if (input_size < 0) {
667 sg_remove_request(sfp, srp);
668 return -EIO; /* User did not pass enough bytes for this command. */
669 }
670 hp = &srp->header;
671 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
672 hp->cmd_len = (unsigned char) cmd_size;
673 hp->iovec_count = 0;
674 hp->mx_sb_len = 0;
675 if (input_size > 0)
676 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
677 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
678 else
679 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
680 hp->dxfer_len = mxsize;
681 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
682 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
683 hp->dxferp = (char __user *)buf + cmd_size;
684 else
685 hp->dxferp = NULL;
686 hp->sbp = NULL;
687 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
688 hp->flags = input_size; /* structure abuse ... */
689 hp->pack_id = old_hdr.pack_id;
690 hp->usr_ptr = NULL;
691 if (copy_from_user(cmnd, buf, cmd_size)) {
692 sg_remove_request(sfp, srp);
693 return -EFAULT;
694 }
695 /*
696 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
697 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
698 * is a non-zero input_size, so emit a warning.
699 */
700 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
701 printk_ratelimited(KERN_WARNING
702 "sg_write: data in/out %d/%d bytes "
703 "for SCSI command 0x%x-- guessing "
704 "data in;\n program %s not setting "
705 "count and/or reply_len properly\n",
706 old_hdr.reply_len - (int)SZ_SG_HEADER,
707 input_size, (unsigned int) cmnd[0],
708 current->comm);
709 }
710 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
711 return (k < 0) ? k : count;
712 }
713
714 static ssize_t
715 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
716 size_t count, int blocking, int read_only, int sg_io_owned,
717 Sg_request **o_srp)
718 {
719 int k;
720 Sg_request *srp;
721 sg_io_hdr_t *hp;
722 unsigned char cmnd[SG_MAX_CDB_SIZE];
723 int timeout;
724 unsigned long ul_timeout;
725
726 if (count < SZ_SG_IO_HDR)
727 return -EINVAL;
728
729 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
730 if (!(srp = sg_add_request(sfp))) {
731 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
732 "sg_new_write: queue full\n"));
733 return -EDOM;
734 }
735 srp->sg_io_owned = sg_io_owned;
736 hp = &srp->header;
737 if (get_sg_io_hdr(hp, buf)) {
738 sg_remove_request(sfp, srp);
739 return -EFAULT;
740 }
741 if (hp->interface_id != 'S') {
742 sg_remove_request(sfp, srp);
743 return -ENOSYS;
744 }
745 if (hp->flags & SG_FLAG_MMAP_IO) {
746 if (hp->dxfer_len > sfp->reserve.bufflen) {
747 sg_remove_request(sfp, srp);
748 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
749 }
750 if (hp->flags & SG_FLAG_DIRECT_IO) {
751 sg_remove_request(sfp, srp);
752 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
753 }
754 if (sfp->res_in_use) {
755 sg_remove_request(sfp, srp);
756 return -EBUSY; /* reserve buffer already being used */
757 }
758 }
759 ul_timeout = msecs_to_jiffies(srp->header.timeout);
760 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
761 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
762 sg_remove_request(sfp, srp);
763 return -EMSGSIZE;
764 }
765 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
766 sg_remove_request(sfp, srp);
767 return -EFAULT;
768 }
769 if (read_only && sg_allow_access(file, cmnd)) {
770 sg_remove_request(sfp, srp);
771 return -EPERM;
772 }
773 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
774 if (k < 0)
775 return k;
776 if (o_srp)
777 *o_srp = srp;
778 return count;
779 }
780
781 static int
782 sg_common_write(Sg_fd * sfp, Sg_request * srp,
783 unsigned char *cmnd, int timeout, int blocking)
784 {
785 int k, at_head;
786 Sg_device *sdp = sfp->parentdp;
787 sg_io_hdr_t *hp = &srp->header;
788
789 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
790 hp->status = 0;
791 hp->masked_status = 0;
792 hp->msg_status = 0;
793 hp->info = 0;
794 hp->host_status = 0;
795 hp->driver_status = 0;
796 hp->resid = 0;
797 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
798 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
799 (int) cmnd[0], (int) hp->cmd_len));
800
801 if (hp->dxfer_len >= SZ_256M) {
802 sg_remove_request(sfp, srp);
803 return -EINVAL;
804 }
805
806 k = sg_start_req(srp, cmnd);
807 if (k) {
808 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
809 "sg_common_write: start_req err=%d\n", k));
810 sg_finish_rem_req(srp);
811 sg_remove_request(sfp, srp);
812 return k; /* probably out of space --> ENOMEM */
813 }
814 if (atomic_read(&sdp->detaching)) {
815 if (srp->bio) {
816 blk_mq_free_request(srp->rq);
817 srp->rq = NULL;
818 }
819
820 sg_finish_rem_req(srp);
821 sg_remove_request(sfp, srp);
822 return -ENODEV;
823 }
824
825 hp->duration = jiffies_to_msecs(jiffies);
826 if (hp->interface_id != '\0' && /* v3 (or later) interface */
827 (SG_FLAG_Q_AT_TAIL & hp->flags))
828 at_head = 0;
829 else
830 at_head = 1;
831
832 srp->rq->timeout = timeout;
833 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
834 srp->rq->end_io = sg_rq_end_io;
835 blk_execute_rq_nowait(srp->rq, at_head);
836 return 0;
837 }
838
839 static int srp_done(Sg_fd *sfp, Sg_request *srp)
840 {
841 unsigned long flags;
842 int ret;
843
844 read_lock_irqsave(&sfp->rq_list_lock, flags);
845 ret = srp->done;
846 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
847 return ret;
848 }
849
850 static int max_sectors_bytes(struct request_queue *q)
851 {
852 unsigned int max_sectors = queue_max_sectors(q);
853
854 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
855
856 return max_sectors << 9;
857 }
858
859 static void
860 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
861 {
862 Sg_request *srp;
863 int val;
864 unsigned int ms;
865
866 val = 0;
867 list_for_each_entry(srp, &sfp->rq_list, entry) {
868 if (val >= SG_MAX_QUEUE)
869 break;
870 rinfo[val].req_state = srp->done + 1;
871 rinfo[val].problem =
872 srp->header.masked_status &
873 srp->header.host_status &
874 srp->header.driver_status;
875 if (srp->done)
876 rinfo[val].duration =
877 srp->header.duration;
878 else {
879 ms = jiffies_to_msecs(jiffies);
880 rinfo[val].duration =
881 (ms > srp->header.duration) ?
882 (ms - srp->header.duration) : 0;
883 }
884 rinfo[val].orphan = srp->orphan;
885 rinfo[val].sg_io_owned = srp->sg_io_owned;
886 rinfo[val].pack_id = srp->header.pack_id;
887 rinfo[val].usr_ptr = srp->header.usr_ptr;
888 val++;
889 }
890 }
891
892 #ifdef CONFIG_COMPAT
893 struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
894 char req_state;
895 char orphan;
896 char sg_io_owned;
897 char problem;
898 int pack_id;
899 compat_uptr_t usr_ptr;
900 unsigned int duration;
901 int unused;
902 };
903
904 static int put_compat_request_table(struct compat_sg_req_info __user *o,
905 struct sg_req_info *rinfo)
906 {
907 int i;
908 for (i = 0; i < SG_MAX_QUEUE; i++) {
909 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
910 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
911 put_user(rinfo[i].duration, &o[i].duration) ||
912 put_user(rinfo[i].unused, &o[i].unused))
913 return -EFAULT;
914 }
915 return 0;
916 }
917 #endif
918
919 static long
920 sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
921 unsigned int cmd_in, void __user *p)
922 {
923 int __user *ip = p;
924 int result, val, read_only;
925 Sg_request *srp;
926 unsigned long iflags;
927
928 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
929 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
930 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
931
932 switch (cmd_in) {
933 case SG_IO:
934 if (atomic_read(&sdp->detaching))
935 return -ENODEV;
936 if (!scsi_block_when_processing_errors(sdp->device))
937 return -ENXIO;
938 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
939 1, read_only, 1, &srp);
940 if (result < 0)
941 return result;
942 result = wait_event_interruptible(sfp->read_wait,
943 srp_done(sfp, srp));
944 write_lock_irq(&sfp->rq_list_lock);
945 if (srp->done) {
946 srp->done = 2;
947 write_unlock_irq(&sfp->rq_list_lock);
948 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
949 return (result < 0) ? result : 0;
950 }
951 srp->orphan = 1;
952 write_unlock_irq(&sfp->rq_list_lock);
953 return result; /* -ERESTARTSYS because signal hit process */
954 case SG_SET_TIMEOUT:
955 result = get_user(val, ip);
956 if (result)
957 return result;
958 if (val < 0)
959 return -EIO;
960 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
961 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
962 INT_MAX);
963 sfp->timeout_user = val;
964 sfp->timeout = mult_frac(val, HZ, USER_HZ);
965
966 return 0;
967 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
968 /* strange ..., for backward compatibility */
969 return sfp->timeout_user;
970 case SG_SET_FORCE_LOW_DMA:
971 /*
972 * N.B. This ioctl never worked properly, but failed to
973 * return an error value. So returning '0' to keep compability
974 * with legacy applications.
975 */
976 return 0;
977 case SG_GET_LOW_DMA:
978 return put_user(0, ip);
979 case SG_GET_SCSI_ID:
980 {
981 sg_scsi_id_t v;
982
983 if (atomic_read(&sdp->detaching))
984 return -ENODEV;
985 memset(&v, 0, sizeof(v));
986 v.host_no = sdp->device->host->host_no;
987 v.channel = sdp->device->channel;
988 v.scsi_id = sdp->device->id;
989 v.lun = sdp->device->lun;
990 v.scsi_type = sdp->device->type;
991 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
992 v.d_queue_depth = sdp->device->queue_depth;
993 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
994 return -EFAULT;
995 return 0;
996 }
997 case SG_SET_FORCE_PACK_ID:
998 result = get_user(val, ip);
999 if (result)
1000 return result;
1001 sfp->force_packid = val ? 1 : 0;
1002 return 0;
1003 case SG_GET_PACK_ID:
1004 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1005 list_for_each_entry(srp, &sfp->rq_list, entry) {
1006 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1007 read_unlock_irqrestore(&sfp->rq_list_lock,
1008 iflags);
1009 return put_user(srp->header.pack_id, ip);
1010 }
1011 }
1012 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1013 return put_user(-1, ip);
1014 case SG_GET_NUM_WAITING:
1015 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1016 val = 0;
1017 list_for_each_entry(srp, &sfp->rq_list, entry) {
1018 if ((1 == srp->done) && (!srp->sg_io_owned))
1019 ++val;
1020 }
1021 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1022 return put_user(val, ip);
1023 case SG_GET_SG_TABLESIZE:
1024 return put_user(sdp->sg_tablesize, ip);
1025 case SG_SET_RESERVED_SIZE:
1026 result = get_user(val, ip);
1027 if (result)
1028 return result;
1029 if (val < 0)
1030 return -EINVAL;
1031 val = min_t(int, val,
1032 max_sectors_bytes(sdp->device->request_queue));
1033 mutex_lock(&sfp->f_mutex);
1034 if (val != sfp->reserve.bufflen) {
1035 if (sfp->mmap_called ||
1036 sfp->res_in_use) {
1037 mutex_unlock(&sfp->f_mutex);
1038 return -EBUSY;
1039 }
1040
1041 sg_remove_scat(sfp, &sfp->reserve);
1042 sg_build_reserve(sfp, val);
1043 }
1044 mutex_unlock(&sfp->f_mutex);
1045 return 0;
1046 case SG_GET_RESERVED_SIZE:
1047 val = min_t(int, sfp->reserve.bufflen,
1048 max_sectors_bytes(sdp->device->request_queue));
1049 return put_user(val, ip);
1050 case SG_SET_COMMAND_Q:
1051 result = get_user(val, ip);
1052 if (result)
1053 return result;
1054 sfp->cmd_q = val ? 1 : 0;
1055 return 0;
1056 case SG_GET_COMMAND_Q:
1057 return put_user((int) sfp->cmd_q, ip);
1058 case SG_SET_KEEP_ORPHAN:
1059 result = get_user(val, ip);
1060 if (result)
1061 return result;
1062 sfp->keep_orphan = val;
1063 return 0;
1064 case SG_GET_KEEP_ORPHAN:
1065 return put_user((int) sfp->keep_orphan, ip);
1066 case SG_NEXT_CMD_LEN:
1067 result = get_user(val, ip);
1068 if (result)
1069 return result;
1070 if (val > SG_MAX_CDB_SIZE)
1071 return -ENOMEM;
1072 sfp->next_cmd_len = (val > 0) ? val : 0;
1073 return 0;
1074 case SG_GET_VERSION_NUM:
1075 return put_user(sg_version_num, ip);
1076 case SG_GET_ACCESS_COUNT:
1077 /* faked - we don't have a real access count anymore */
1078 val = (sdp->device ? 1 : 0);
1079 return put_user(val, ip);
1080 case SG_GET_REQUEST_TABLE:
1081 {
1082 sg_req_info_t *rinfo;
1083
1084 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1085 GFP_KERNEL);
1086 if (!rinfo)
1087 return -ENOMEM;
1088 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1089 sg_fill_request_table(sfp, rinfo);
1090 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1091 #ifdef CONFIG_COMPAT
1092 if (in_compat_syscall())
1093 result = put_compat_request_table(p, rinfo);
1094 else
1095 #endif
1096 result = copy_to_user(p, rinfo,
1097 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1098 result = result ? -EFAULT : 0;
1099 kfree(rinfo);
1100 return result;
1101 }
1102 case SG_EMULATED_HOST:
1103 if (atomic_read(&sdp->detaching))
1104 return -ENODEV;
1105 return put_user(sdp->device->host->hostt->emulated, ip);
1106 case SCSI_IOCTL_SEND_COMMAND:
1107 if (atomic_read(&sdp->detaching))
1108 return -ENODEV;
1109 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE,
1110 cmd_in, p);
1111 case SG_SET_DEBUG:
1112 result = get_user(val, ip);
1113 if (result)
1114 return result;
1115 sdp->sgdebug = (char) val;
1116 return 0;
1117 case BLKSECTGET:
1118 return put_user(max_sectors_bytes(sdp->device->request_queue),
1119 ip);
1120 case BLKTRACESETUP:
1121 return blk_trace_setup(sdp->device->request_queue, sdp->name,
1122 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1123 NULL, p);
1124 case BLKTRACESTART:
1125 return blk_trace_startstop(sdp->device->request_queue, 1);
1126 case BLKTRACESTOP:
1127 return blk_trace_startstop(sdp->device->request_queue, 0);
1128 case BLKTRACETEARDOWN:
1129 return blk_trace_remove(sdp->device->request_queue);
1130 case SCSI_IOCTL_GET_IDLUN:
1131 case SCSI_IOCTL_GET_BUS_NUMBER:
1132 case SCSI_IOCTL_PROBE_HOST:
1133 case SG_GET_TRANSFORM:
1134 case SG_SCSI_RESET:
1135 if (atomic_read(&sdp->detaching))
1136 return -ENODEV;
1137 break;
1138 default:
1139 if (read_only)
1140 return -EPERM; /* don't know so take safe approach */
1141 break;
1142 }
1143
1144 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1145 cmd_in, filp->f_flags & O_NDELAY);
1146 if (result)
1147 return result;
1148
1149 return -ENOIOCTLCMD;
1150 }
1151
1152 static long
1153 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1154 {
1155 void __user *p = (void __user *)arg;
1156 Sg_device *sdp;
1157 Sg_fd *sfp;
1158 int ret;
1159
1160 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1161 return -ENXIO;
1162
1163 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1164 if (ret != -ENOIOCTLCMD)
1165 return ret;
1166 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE, cmd_in, p);
1167 }
1168
1169 static __poll_t
1170 sg_poll(struct file *filp, poll_table * wait)
1171 {
1172 __poll_t res = 0;
1173 Sg_device *sdp;
1174 Sg_fd *sfp;
1175 Sg_request *srp;
1176 int count = 0;
1177 unsigned long iflags;
1178
1179 sfp = filp->private_data;
1180 if (!sfp)
1181 return EPOLLERR;
1182 sdp = sfp->parentdp;
1183 if (!sdp)
1184 return EPOLLERR;
1185 poll_wait(filp, &sfp->read_wait, wait);
1186 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1187 list_for_each_entry(srp, &sfp->rq_list, entry) {
1188 /* if any read waiting, flag it */
1189 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1190 res = EPOLLIN | EPOLLRDNORM;
1191 ++count;
1192 }
1193 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1194
1195 if (atomic_read(&sdp->detaching))
1196 res |= EPOLLHUP;
1197 else if (!sfp->cmd_q) {
1198 if (0 == count)
1199 res |= EPOLLOUT | EPOLLWRNORM;
1200 } else if (count < SG_MAX_QUEUE)
1201 res |= EPOLLOUT | EPOLLWRNORM;
1202 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1203 "sg_poll: res=0x%x\n", (__force u32) res));
1204 return res;
1205 }
1206
1207 static int
1208 sg_fasync(int fd, struct file *filp, int mode)
1209 {
1210 Sg_device *sdp;
1211 Sg_fd *sfp;
1212
1213 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1214 return -ENXIO;
1215 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1216 "sg_fasync: mode=%d\n", mode));
1217
1218 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1219 }
1220
1221 static vm_fault_t
1222 sg_vma_fault(struct vm_fault *vmf)
1223 {
1224 struct vm_area_struct *vma = vmf->vma;
1225 Sg_fd *sfp;
1226 unsigned long offset, len, sa;
1227 Sg_scatter_hold *rsv_schp;
1228 int k, length;
1229
1230 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1231 return VM_FAULT_SIGBUS;
1232 rsv_schp = &sfp->reserve;
1233 offset = vmf->pgoff << PAGE_SHIFT;
1234 if (offset >= rsv_schp->bufflen)
1235 return VM_FAULT_SIGBUS;
1236 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1237 "sg_vma_fault: offset=%lu, scatg=%d\n",
1238 offset, rsv_schp->k_use_sg));
1239 sa = vma->vm_start;
1240 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1241 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1242 len = vma->vm_end - sa;
1243 len = (len < length) ? len : length;
1244 if (offset < len) {
1245 struct page *page = nth_page(rsv_schp->pages[k],
1246 offset >> PAGE_SHIFT);
1247 get_page(page); /* increment page count */
1248 vmf->page = page;
1249 return 0; /* success */
1250 }
1251 sa += len;
1252 offset -= len;
1253 }
1254
1255 return VM_FAULT_SIGBUS;
1256 }
1257
1258 static const struct vm_operations_struct sg_mmap_vm_ops = {
1259 .fault = sg_vma_fault,
1260 };
1261
1262 static int
1263 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1264 {
1265 Sg_fd *sfp;
1266 unsigned long req_sz, len, sa;
1267 Sg_scatter_hold *rsv_schp;
1268 int k, length;
1269 int ret = 0;
1270
1271 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1272 return -ENXIO;
1273 req_sz = vma->vm_end - vma->vm_start;
1274 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1275 "sg_mmap starting, vm_start=%p, len=%d\n",
1276 (void *) vma->vm_start, (int) req_sz));
1277 if (vma->vm_pgoff)
1278 return -EINVAL; /* want no offset */
1279 rsv_schp = &sfp->reserve;
1280 mutex_lock(&sfp->f_mutex);
1281 if (req_sz > rsv_schp->bufflen) {
1282 ret = -ENOMEM; /* cannot map more than reserved buffer */
1283 goto out;
1284 }
1285
1286 sa = vma->vm_start;
1287 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1288 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1289 len = vma->vm_end - sa;
1290 len = (len < length) ? len : length;
1291 sa += len;
1292 }
1293
1294 sfp->mmap_called = 1;
1295 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP);
1296 vma->vm_private_data = sfp;
1297 vma->vm_ops = &sg_mmap_vm_ops;
1298 out:
1299 mutex_unlock(&sfp->f_mutex);
1300 return ret;
1301 }
1302
1303 static void
1304 sg_rq_end_io_usercontext(struct work_struct *work)
1305 {
1306 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1307 struct sg_fd *sfp = srp->parentfp;
1308
1309 sg_finish_rem_req(srp);
1310 sg_remove_request(sfp, srp);
1311 kref_put(&sfp->f_ref, sg_remove_sfp);
1312 }
1313
1314 /*
1315 * This function is a "bottom half" handler that is called by the mid
1316 * level when a command is completed (or has failed).
1317 */
1318 static enum rq_end_io_ret
1319 sg_rq_end_io(struct request *rq, blk_status_t status)
1320 {
1321 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
1322 struct sg_request *srp = rq->end_io_data;
1323 Sg_device *sdp;
1324 Sg_fd *sfp;
1325 unsigned long iflags;
1326 unsigned int ms;
1327 char *sense;
1328 int result, resid, done = 1;
1329
1330 if (WARN_ON(srp->done != 0))
1331 return RQ_END_IO_NONE;
1332
1333 sfp = srp->parentfp;
1334 if (WARN_ON(sfp == NULL))
1335 return RQ_END_IO_NONE;
1336
1337 sdp = sfp->parentdp;
1338 if (unlikely(atomic_read(&sdp->detaching)))
1339 pr_info("%s: device detaching\n", __func__);
1340
1341 sense = scmd->sense_buffer;
1342 result = scmd->result;
1343 resid = scmd->resid_len;
1344
1345 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1346 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1347 srp->header.pack_id, result));
1348 srp->header.resid = resid;
1349 ms = jiffies_to_msecs(jiffies);
1350 srp->header.duration = (ms > srp->header.duration) ?
1351 (ms - srp->header.duration) : 0;
1352 if (0 != result) {
1353 struct scsi_sense_hdr sshdr;
1354
1355 srp->header.status = 0xff & result;
1356 srp->header.masked_status = sg_status_byte(result);
1357 srp->header.msg_status = COMMAND_COMPLETE;
1358 srp->header.host_status = host_byte(result);
1359 srp->header.driver_status = driver_byte(result);
1360 if ((sdp->sgdebug > 0) &&
1361 ((CHECK_CONDITION == srp->header.masked_status) ||
1362 (COMMAND_TERMINATED == srp->header.masked_status)))
1363 __scsi_print_sense(sdp->device, __func__, sense,
1364 SCSI_SENSE_BUFFERSIZE);
1365
1366 /* Following if statement is a patch supplied by Eric Youngdale */
1367 if (driver_byte(result) != 0
1368 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1369 && !scsi_sense_is_deferred(&sshdr)
1370 && sshdr.sense_key == UNIT_ATTENTION
1371 && sdp->device->removable) {
1372 /* Detected possible disc change. Set the bit - this */
1373 /* may be used if there are filesystems using this device */
1374 sdp->device->changed = 1;
1375 }
1376 }
1377
1378 if (scmd->sense_len)
1379 memcpy(srp->sense_b, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
1380
1381 /* Rely on write phase to clean out srp status values, so no "else" */
1382
1383 /*
1384 * Free the request as soon as it is complete so that its resources
1385 * can be reused without waiting for userspace to read() the
1386 * result. But keep the associated bio (if any) around until
1387 * blk_rq_unmap_user() can be called from user context.
1388 */
1389 srp->rq = NULL;
1390 blk_mq_free_request(rq);
1391
1392 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1393 if (unlikely(srp->orphan)) {
1394 if (sfp->keep_orphan)
1395 srp->sg_io_owned = 0;
1396 else
1397 done = 0;
1398 }
1399 srp->done = done;
1400 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1401
1402 if (likely(done)) {
1403 /* Now wake up any sg_read() that is waiting for this
1404 * packet.
1405 */
1406 wake_up_interruptible(&sfp->read_wait);
1407 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1408 kref_put(&sfp->f_ref, sg_remove_sfp);
1409 } else {
1410 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1411 schedule_work(&srp->ew.work);
1412 }
1413 return RQ_END_IO_NONE;
1414 }
1415
1416 static const struct file_operations sg_fops = {
1417 .owner = THIS_MODULE,
1418 .read = sg_read,
1419 .write = sg_write,
1420 .poll = sg_poll,
1421 .unlocked_ioctl = sg_ioctl,
1422 .compat_ioctl = compat_ptr_ioctl,
1423 .open = sg_open,
1424 .mmap = sg_mmap,
1425 .release = sg_release,
1426 .fasync = sg_fasync,
1427 };
1428
1429 static const struct class sg_sysfs_class = {
1430 .name = "scsi_generic"
1431 };
1432
1433 static int sg_sysfs_valid = 0;
1434
1435 static Sg_device *
1436 sg_alloc(struct scsi_device *scsidp)
1437 {
1438 struct request_queue *q = scsidp->request_queue;
1439 Sg_device *sdp;
1440 unsigned long iflags;
1441 int error;
1442 u32 k;
1443
1444 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1445 if (!sdp) {
1446 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1447 "failure\n", __func__);
1448 return ERR_PTR(-ENOMEM);
1449 }
1450
1451 idr_preload(GFP_KERNEL);
1452 write_lock_irqsave(&sg_index_lock, iflags);
1453
1454 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1455 if (error < 0) {
1456 if (error == -ENOSPC) {
1457 sdev_printk(KERN_WARNING, scsidp,
1458 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1459 scsidp->type, SG_MAX_DEVS - 1);
1460 error = -ENODEV;
1461 } else {
1462 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1463 "allocation Sg_device failure: %d\n",
1464 __func__, error);
1465 }
1466 goto out_unlock;
1467 }
1468 k = error;
1469
1470 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1471 "sg_alloc: dev=%d \n", k));
1472 sprintf(sdp->name, "sg%d", k);
1473 sdp->device = scsidp;
1474 mutex_init(&sdp->open_rel_lock);
1475 INIT_LIST_HEAD(&sdp->sfds);
1476 init_waitqueue_head(&sdp->open_wait);
1477 atomic_set(&sdp->detaching, 0);
1478 rwlock_init(&sdp->sfd_lock);
1479 sdp->sg_tablesize = queue_max_segments(q);
1480 sdp->index = k;
1481 kref_init(&sdp->d_ref);
1482 error = 0;
1483
1484 out_unlock:
1485 write_unlock_irqrestore(&sg_index_lock, iflags);
1486 idr_preload_end();
1487
1488 if (error) {
1489 kfree(sdp);
1490 return ERR_PTR(error);
1491 }
1492 return sdp;
1493 }
1494
1495 static int
1496 sg_add_device(struct device *cl_dev)
1497 {
1498 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1499 Sg_device *sdp = NULL;
1500 struct cdev * cdev = NULL;
1501 int error;
1502 unsigned long iflags;
1503
1504 if (!blk_get_queue(scsidp->request_queue)) {
1505 pr_warn("%s: get scsi_device queue failed\n", __func__);
1506 return -ENODEV;
1507 }
1508
1509 error = -ENOMEM;
1510 cdev = cdev_alloc();
1511 if (!cdev) {
1512 pr_warn("%s: cdev_alloc failed\n", __func__);
1513 goto out;
1514 }
1515 cdev->owner = THIS_MODULE;
1516 cdev->ops = &sg_fops;
1517
1518 sdp = sg_alloc(scsidp);
1519 if (IS_ERR(sdp)) {
1520 pr_warn("%s: sg_alloc failed\n", __func__);
1521 error = PTR_ERR(sdp);
1522 goto out;
1523 }
1524
1525 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1526 if (error)
1527 goto cdev_add_err;
1528
1529 sdp->cdev = cdev;
1530 if (sg_sysfs_valid) {
1531 struct device *sg_class_member;
1532
1533 sg_class_member = device_create(&sg_sysfs_class, cl_dev->parent,
1534 MKDEV(SCSI_GENERIC_MAJOR,
1535 sdp->index),
1536 sdp, "%s", sdp->name);
1537 if (IS_ERR(sg_class_member)) {
1538 pr_err("%s: device_create failed\n", __func__);
1539 error = PTR_ERR(sg_class_member);
1540 goto cdev_add_err;
1541 }
1542 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1543 &sg_class_member->kobj, "generic");
1544 if (error)
1545 pr_err("%s: unable to make symlink 'generic' back "
1546 "to sg%d\n", __func__, sdp->index);
1547 } else
1548 pr_warn("%s: sg_sys Invalid\n", __func__);
1549
1550 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1551 "type %d\n", sdp->index, scsidp->type);
1552
1553 dev_set_drvdata(cl_dev, sdp);
1554
1555 return 0;
1556
1557 cdev_add_err:
1558 write_lock_irqsave(&sg_index_lock, iflags);
1559 idr_remove(&sg_index_idr, sdp->index);
1560 write_unlock_irqrestore(&sg_index_lock, iflags);
1561 kfree(sdp);
1562
1563 out:
1564 if (cdev)
1565 cdev_del(cdev);
1566 blk_put_queue(scsidp->request_queue);
1567 return error;
1568 }
1569
1570 static void
1571 sg_device_destroy(struct kref *kref)
1572 {
1573 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1574 struct request_queue *q = sdp->device->request_queue;
1575 unsigned long flags;
1576
1577 /* CAUTION! Note that the device can still be found via idr_find()
1578 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1579 * any other cleanup.
1580 */
1581
1582 blk_trace_remove(q);
1583 blk_put_queue(q);
1584
1585 write_lock_irqsave(&sg_index_lock, flags);
1586 idr_remove(&sg_index_idr, sdp->index);
1587 write_unlock_irqrestore(&sg_index_lock, flags);
1588
1589 SCSI_LOG_TIMEOUT(3,
1590 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1591
1592 kfree(sdp);
1593 }
1594
1595 static void
1596 sg_remove_device(struct device *cl_dev)
1597 {
1598 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1599 Sg_device *sdp = dev_get_drvdata(cl_dev);
1600 unsigned long iflags;
1601 Sg_fd *sfp;
1602 int val;
1603
1604 if (!sdp)
1605 return;
1606 /* want sdp->detaching non-zero as soon as possible */
1607 val = atomic_inc_return(&sdp->detaching);
1608 if (val > 1)
1609 return; /* only want to do following once per device */
1610
1611 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1612 "%s\n", __func__));
1613
1614 read_lock_irqsave(&sdp->sfd_lock, iflags);
1615 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1616 wake_up_interruptible_all(&sfp->read_wait);
1617 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1618 }
1619 wake_up_interruptible_all(&sdp->open_wait);
1620 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1621
1622 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1623 device_destroy(&sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1624 cdev_del(sdp->cdev);
1625 sdp->cdev = NULL;
1626
1627 kref_put(&sdp->d_ref, sg_device_destroy);
1628 }
1629
1630 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1631 module_param_named(def_reserved_size, def_reserved_size, int,
1632 S_IRUGO | S_IWUSR);
1633 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1634
1635 MODULE_AUTHOR("Douglas Gilbert");
1636 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1637 MODULE_LICENSE("GPL");
1638 MODULE_VERSION(SG_VERSION_STR);
1639 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1640
1641 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1642 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1643 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1644 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1645
1646 #ifdef CONFIG_SYSCTL
1647 #include <linux/sysctl.h>
1648
1649 static struct ctl_table sg_sysctls[] = {
1650 {
1651 .procname = "sg-big-buff",
1652 .data = &sg_big_buff,
1653 .maxlen = sizeof(int),
1654 .mode = 0444,
1655 .proc_handler = proc_dointvec,
1656 },
1657 };
1658
1659 static struct ctl_table_header *hdr;
1660 static void register_sg_sysctls(void)
1661 {
1662 if (!hdr)
1663 hdr = register_sysctl("kernel", sg_sysctls);
1664 }
1665
1666 static void unregister_sg_sysctls(void)
1667 {
1668 if (hdr)
1669 unregister_sysctl_table(hdr);
1670 }
1671 #else
1672 #define register_sg_sysctls() do { } while (0)
1673 #define unregister_sg_sysctls() do { } while (0)
1674 #endif /* CONFIG_SYSCTL */
1675
1676 static int __init
1677 init_sg(void)
1678 {
1679 int rc;
1680
1681 if (scatter_elem_sz < PAGE_SIZE) {
1682 scatter_elem_sz = PAGE_SIZE;
1683 scatter_elem_sz_prev = scatter_elem_sz;
1684 }
1685 if (def_reserved_size >= 0)
1686 sg_big_buff = def_reserved_size;
1687 else
1688 def_reserved_size = sg_big_buff;
1689
1690 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1691 SG_MAX_DEVS, "sg");
1692 if (rc)
1693 return rc;
1694 rc = class_register(&sg_sysfs_class);
1695 if (rc)
1696 goto err_out;
1697 sg_sysfs_valid = 1;
1698 rc = scsi_register_interface(&sg_interface);
1699 if (0 == rc) {
1700 #ifdef CONFIG_SCSI_PROC_FS
1701 sg_proc_init();
1702 #endif /* CONFIG_SCSI_PROC_FS */
1703 return 0;
1704 }
1705 class_unregister(&sg_sysfs_class);
1706 register_sg_sysctls();
1707 err_out:
1708 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1709 return rc;
1710 }
1711
1712 static void __exit
1713 exit_sg(void)
1714 {
1715 unregister_sg_sysctls();
1716 #ifdef CONFIG_SCSI_PROC_FS
1717 remove_proc_subtree("scsi/sg", NULL);
1718 #endif /* CONFIG_SCSI_PROC_FS */
1719 scsi_unregister_interface(&sg_interface);
1720 class_unregister(&sg_sysfs_class);
1721 sg_sysfs_valid = 0;
1722 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1723 SG_MAX_DEVS);
1724 idr_destroy(&sg_index_idr);
1725 }
1726
1727 static int
1728 sg_start_req(Sg_request *srp, unsigned char *cmd)
1729 {
1730 int res;
1731 struct request *rq;
1732 Sg_fd *sfp = srp->parentfp;
1733 sg_io_hdr_t *hp = &srp->header;
1734 int dxfer_len = (int) hp->dxfer_len;
1735 int dxfer_dir = hp->dxfer_direction;
1736 unsigned int iov_count = hp->iovec_count;
1737 Sg_scatter_hold *req_schp = &srp->data;
1738 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1739 struct request_queue *q = sfp->parentdp->device->request_queue;
1740 struct rq_map_data *md, map_data;
1741 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? ITER_SOURCE : ITER_DEST;
1742 struct scsi_cmnd *scmd;
1743
1744 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1745 "sg_start_req: dxfer_len=%d\n",
1746 dxfer_len));
1747
1748 /*
1749 * NOTE
1750 *
1751 * With scsi-mq enabled, there are a fixed number of preallocated
1752 * requests equal in number to shost->can_queue. If all of the
1753 * preallocated requests are already in use, then scsi_alloc_request()
1754 * will sleep until an active command completes, freeing up a request.
1755 * Although waiting in an asynchronous interface is less than ideal, we
1756 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1757 * not expect an EWOULDBLOCK from this condition.
1758 */
1759 rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1760 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
1761 if (IS_ERR(rq))
1762 return PTR_ERR(rq);
1763 scmd = blk_mq_rq_to_pdu(rq);
1764
1765 if (hp->cmd_len > sizeof(scmd->cmnd)) {
1766 blk_mq_free_request(rq);
1767 return -EINVAL;
1768 }
1769
1770 memcpy(scmd->cmnd, cmd, hp->cmd_len);
1771 scmd->cmd_len = hp->cmd_len;
1772
1773 srp->rq = rq;
1774 rq->end_io_data = srp;
1775 scmd->allowed = SG_DEFAULT_RETRIES;
1776
1777 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1778 return 0;
1779
1780 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1781 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1782 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1783 md = NULL;
1784 else
1785 md = &map_data;
1786
1787 if (md) {
1788 mutex_lock(&sfp->f_mutex);
1789 if (dxfer_len <= rsv_schp->bufflen &&
1790 !sfp->res_in_use) {
1791 sfp->res_in_use = 1;
1792 sg_link_reserve(sfp, srp, dxfer_len);
1793 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1794 res = -EBUSY; /* sfp->res_in_use == 1 */
1795 if (dxfer_len > rsv_schp->bufflen)
1796 res = -ENOMEM;
1797 mutex_unlock(&sfp->f_mutex);
1798 return res;
1799 } else {
1800 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1801 if (res) {
1802 mutex_unlock(&sfp->f_mutex);
1803 return res;
1804 }
1805 }
1806 mutex_unlock(&sfp->f_mutex);
1807
1808 md->pages = req_schp->pages;
1809 md->page_order = req_schp->page_order;
1810 md->nr_entries = req_schp->k_use_sg;
1811 md->offset = 0;
1812 md->null_mapped = hp->dxferp ? 0 : 1;
1813 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1814 md->from_user = 1;
1815 else
1816 md->from_user = 0;
1817 }
1818
1819 res = blk_rq_map_user_io(rq, md, hp->dxferp, hp->dxfer_len,
1820 GFP_ATOMIC, iov_count, iov_count, 1, rw);
1821 if (!res) {
1822 srp->bio = rq->bio;
1823
1824 if (!md) {
1825 req_schp->dio_in_use = 1;
1826 hp->info |= SG_INFO_DIRECT_IO;
1827 }
1828 }
1829 return res;
1830 }
1831
1832 static int
1833 sg_finish_rem_req(Sg_request *srp)
1834 {
1835 int ret = 0;
1836
1837 Sg_fd *sfp = srp->parentfp;
1838 Sg_scatter_hold *req_schp = &srp->data;
1839
1840 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1841 "sg_finish_rem_req: res_used=%d\n",
1842 (int) srp->res_used));
1843 if (srp->bio)
1844 ret = blk_rq_unmap_user(srp->bio);
1845
1846 if (srp->rq)
1847 blk_mq_free_request(srp->rq);
1848
1849 if (srp->res_used)
1850 sg_unlink_reserve(sfp, srp);
1851 else
1852 sg_remove_scat(sfp, req_schp);
1853
1854 return ret;
1855 }
1856
1857 static int
1858 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1859 {
1860 int sg_bufflen = tablesize * sizeof(struct page *);
1861 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1862
1863 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1864 if (!schp->pages)
1865 return -ENOMEM;
1866 schp->sglist_len = sg_bufflen;
1867 return tablesize; /* number of scat_gath elements allocated */
1868 }
1869
1870 static int
1871 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1872 {
1873 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1874 int sg_tablesize = sfp->parentdp->sg_tablesize;
1875 int blk_size = buff_size, order;
1876 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1877
1878 if (blk_size < 0)
1879 return -EFAULT;
1880 if (0 == blk_size)
1881 ++blk_size; /* don't know why */
1882 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1883 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1884 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1885 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1886 buff_size, blk_size));
1887
1888 /* N.B. ret_sz carried into this block ... */
1889 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1890 if (mx_sc_elems < 0)
1891 return mx_sc_elems; /* most likely -ENOMEM */
1892
1893 num = scatter_elem_sz;
1894 if (unlikely(num != scatter_elem_sz_prev)) {
1895 if (num < PAGE_SIZE) {
1896 scatter_elem_sz = PAGE_SIZE;
1897 scatter_elem_sz_prev = PAGE_SIZE;
1898 } else
1899 scatter_elem_sz_prev = num;
1900 }
1901
1902 order = get_order(num);
1903 retry:
1904 ret_sz = 1 << (PAGE_SHIFT + order);
1905
1906 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1907 k++, rem_sz -= ret_sz) {
1908
1909 num = (rem_sz > scatter_elem_sz_prev) ?
1910 scatter_elem_sz_prev : rem_sz;
1911
1912 schp->pages[k] = alloc_pages(gfp_mask, order);
1913 if (!schp->pages[k])
1914 goto out;
1915
1916 if (num == scatter_elem_sz_prev) {
1917 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1918 scatter_elem_sz = ret_sz;
1919 scatter_elem_sz_prev = ret_sz;
1920 }
1921 }
1922
1923 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1924 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1925 k, num, ret_sz));
1926 } /* end of for loop */
1927
1928 schp->page_order = order;
1929 schp->k_use_sg = k;
1930 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1931 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1932 k, rem_sz));
1933
1934 schp->bufflen = blk_size;
1935 if (rem_sz > 0) /* must have failed */
1936 return -ENOMEM;
1937 return 0;
1938 out:
1939 for (i = 0; i < k; i++)
1940 __free_pages(schp->pages[i], order);
1941
1942 if (--order >= 0)
1943 goto retry;
1944
1945 return -ENOMEM;
1946 }
1947
1948 static void
1949 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1950 {
1951 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1952 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1953 if (schp->pages && schp->sglist_len > 0) {
1954 if (!schp->dio_in_use) {
1955 int k;
1956
1957 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1958 SCSI_LOG_TIMEOUT(5,
1959 sg_printk(KERN_INFO, sfp->parentdp,
1960 "sg_remove_scat: k=%d, pg=0x%p\n",
1961 k, schp->pages[k]));
1962 __free_pages(schp->pages[k], schp->page_order);
1963 }
1964
1965 kfree(schp->pages);
1966 }
1967 }
1968 memset(schp, 0, sizeof (*schp));
1969 }
1970
1971 static int
1972 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1973 {
1974 Sg_scatter_hold *schp = &srp->data;
1975 int k, num;
1976
1977 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1978 "sg_read_oxfer: num_read_xfer=%d\n",
1979 num_read_xfer));
1980 if ((!outp) || (num_read_xfer <= 0))
1981 return 0;
1982
1983 num = 1 << (PAGE_SHIFT + schp->page_order);
1984 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1985 if (num > num_read_xfer) {
1986 if (copy_to_user(outp, page_address(schp->pages[k]),
1987 num_read_xfer))
1988 return -EFAULT;
1989 break;
1990 } else {
1991 if (copy_to_user(outp, page_address(schp->pages[k]),
1992 num))
1993 return -EFAULT;
1994 num_read_xfer -= num;
1995 if (num_read_xfer <= 0)
1996 break;
1997 outp += num;
1998 }
1999 }
2000
2001 return 0;
2002 }
2003
2004 static void
2005 sg_build_reserve(Sg_fd * sfp, int req_size)
2006 {
2007 Sg_scatter_hold *schp = &sfp->reserve;
2008
2009 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2010 "sg_build_reserve: req_size=%d\n", req_size));
2011 do {
2012 if (req_size < PAGE_SIZE)
2013 req_size = PAGE_SIZE;
2014 if (0 == sg_build_indirect(schp, sfp, req_size))
2015 return;
2016 else
2017 sg_remove_scat(sfp, schp);
2018 req_size >>= 1; /* divide by 2 */
2019 } while (req_size > (PAGE_SIZE / 2));
2020 }
2021
2022 static void
2023 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2024 {
2025 Sg_scatter_hold *req_schp = &srp->data;
2026 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2027 int k, num, rem;
2028
2029 srp->res_used = 1;
2030 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2031 "sg_link_reserve: size=%d\n", size));
2032 rem = size;
2033
2034 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2035 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2036 if (rem <= num) {
2037 req_schp->k_use_sg = k + 1;
2038 req_schp->sglist_len = rsv_schp->sglist_len;
2039 req_schp->pages = rsv_schp->pages;
2040
2041 req_schp->bufflen = size;
2042 req_schp->page_order = rsv_schp->page_order;
2043 break;
2044 } else
2045 rem -= num;
2046 }
2047
2048 if (k >= rsv_schp->k_use_sg)
2049 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2050 "sg_link_reserve: BAD size\n"));
2051 }
2052
2053 static void
2054 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2055 {
2056 Sg_scatter_hold *req_schp = &srp->data;
2057
2058 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2059 "sg_unlink_reserve: req->k_use_sg=%d\n",
2060 (int) req_schp->k_use_sg));
2061 req_schp->k_use_sg = 0;
2062 req_schp->bufflen = 0;
2063 req_schp->pages = NULL;
2064 req_schp->page_order = 0;
2065 req_schp->sglist_len = 0;
2066 srp->res_used = 0;
2067 /* Called without mutex lock to avoid deadlock */
2068 sfp->res_in_use = 0;
2069 }
2070
2071 static Sg_request *
2072 sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy)
2073 {
2074 Sg_request *resp;
2075 unsigned long iflags;
2076
2077 *busy = false;
2078 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2079 list_for_each_entry(resp, &sfp->rq_list, entry) {
2080 /* look for requests that are not SG_IO owned */
2081 if ((!resp->sg_io_owned) &&
2082 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2083 switch (resp->done) {
2084 case 0: /* request active */
2085 *busy = true;
2086 break;
2087 case 1: /* request done; response ready to return */
2088 resp->done = 2; /* guard against other readers */
2089 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2090 return resp;
2091 case 2: /* response already being returned */
2092 break;
2093 }
2094 }
2095 }
2096 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2097 return NULL;
2098 }
2099
2100 /* always adds to end of list */
2101 static Sg_request *
2102 sg_add_request(Sg_fd * sfp)
2103 {
2104 int k;
2105 unsigned long iflags;
2106 Sg_request *rp = sfp->req_arr;
2107
2108 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2109 if (!list_empty(&sfp->rq_list)) {
2110 if (!sfp->cmd_q)
2111 goto out_unlock;
2112
2113 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2114 if (!rp->parentfp)
2115 break;
2116 }
2117 if (k >= SG_MAX_QUEUE)
2118 goto out_unlock;
2119 }
2120 memset(rp, 0, sizeof (Sg_request));
2121 rp->parentfp = sfp;
2122 rp->header.duration = jiffies_to_msecs(jiffies);
2123 list_add_tail(&rp->entry, &sfp->rq_list);
2124 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2125 return rp;
2126 out_unlock:
2127 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2128 return NULL;
2129 }
2130
2131 /* Return of 1 for found; 0 for not found */
2132 static int
2133 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2134 {
2135 unsigned long iflags;
2136 int res = 0;
2137
2138 if (!sfp || !srp || list_empty(&sfp->rq_list))
2139 return res;
2140 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2141 if (!list_empty(&srp->entry)) {
2142 list_del(&srp->entry);
2143 srp->parentfp = NULL;
2144 res = 1;
2145 }
2146 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2147
2148 /*
2149 * If the device is detaching, wakeup any readers in case we just
2150 * removed the last response, which would leave nothing for them to
2151 * return other than -ENODEV.
2152 */
2153 if (unlikely(atomic_read(&sfp->parentdp->detaching)))
2154 wake_up_interruptible_all(&sfp->read_wait);
2155
2156 return res;
2157 }
2158
2159 static Sg_fd *
2160 sg_add_sfp(Sg_device * sdp)
2161 {
2162 Sg_fd *sfp;
2163 unsigned long iflags;
2164 int bufflen;
2165
2166 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2167 if (!sfp)
2168 return ERR_PTR(-ENOMEM);
2169
2170 init_waitqueue_head(&sfp->read_wait);
2171 rwlock_init(&sfp->rq_list_lock);
2172 INIT_LIST_HEAD(&sfp->rq_list);
2173 kref_init(&sfp->f_ref);
2174 mutex_init(&sfp->f_mutex);
2175 sfp->timeout = SG_DEFAULT_TIMEOUT;
2176 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2177 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2178 sfp->cmd_q = SG_DEF_COMMAND_Q;
2179 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2180 sfp->parentdp = sdp;
2181 write_lock_irqsave(&sdp->sfd_lock, iflags);
2182 if (atomic_read(&sdp->detaching)) {
2183 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2184 kfree(sfp);
2185 return ERR_PTR(-ENODEV);
2186 }
2187 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2188 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2189 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2190 "sg_add_sfp: sfp=0x%p\n", sfp));
2191 if (unlikely(sg_big_buff != def_reserved_size))
2192 sg_big_buff = def_reserved_size;
2193
2194 bufflen = min_t(int, sg_big_buff,
2195 max_sectors_bytes(sdp->device->request_queue));
2196 sg_build_reserve(sfp, bufflen);
2197 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2198 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2199 sfp->reserve.bufflen,
2200 sfp->reserve.k_use_sg));
2201
2202 kref_get(&sdp->d_ref);
2203 __module_get(THIS_MODULE);
2204 return sfp;
2205 }
2206
2207 static void
2208 sg_remove_sfp_usercontext(struct work_struct *work)
2209 {
2210 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2211 struct sg_device *sdp = sfp->parentdp;
2212 struct scsi_device *device = sdp->device;
2213 Sg_request *srp;
2214 unsigned long iflags;
2215
2216 /* Cleanup any responses which were never read(). */
2217 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2218 while (!list_empty(&sfp->rq_list)) {
2219 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2220 sg_finish_rem_req(srp);
2221 list_del(&srp->entry);
2222 srp->parentfp = NULL;
2223 }
2224 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2225
2226 if (sfp->reserve.bufflen > 0) {
2227 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2228 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2229 (int) sfp->reserve.bufflen,
2230 (int) sfp->reserve.k_use_sg));
2231 sg_remove_scat(sfp, &sfp->reserve);
2232 }
2233
2234 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2235 "sg_remove_sfp: sfp=0x%p\n", sfp));
2236 kfree(sfp);
2237
2238 kref_put(&sdp->d_ref, sg_device_destroy);
2239 scsi_device_put(device);
2240 module_put(THIS_MODULE);
2241 }
2242
2243 static void
2244 sg_remove_sfp(struct kref *kref)
2245 {
2246 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2247 struct sg_device *sdp = sfp->parentdp;
2248 unsigned long iflags;
2249
2250 write_lock_irqsave(&sdp->sfd_lock, iflags);
2251 list_del(&sfp->sfd_siblings);
2252 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2253
2254 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2255 schedule_work(&sfp->ew.work);
2256 }
2257
2258 #ifdef CONFIG_SCSI_PROC_FS
2259 static int
2260 sg_idr_max_id(int id, void *p, void *data)
2261 {
2262 int *k = data;
2263
2264 if (*k < id)
2265 *k = id;
2266
2267 return 0;
2268 }
2269
2270 static int
2271 sg_last_dev(void)
2272 {
2273 int k = -1;
2274 unsigned long iflags;
2275
2276 read_lock_irqsave(&sg_index_lock, iflags);
2277 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2278 read_unlock_irqrestore(&sg_index_lock, iflags);
2279 return k + 1; /* origin 1 */
2280 }
2281 #endif
2282
2283 /* must be called with sg_index_lock held */
2284 static Sg_device *sg_lookup_dev(int dev)
2285 {
2286 return idr_find(&sg_index_idr, dev);
2287 }
2288
2289 static Sg_device *
2290 sg_get_dev(int dev)
2291 {
2292 struct sg_device *sdp;
2293 unsigned long flags;
2294
2295 read_lock_irqsave(&sg_index_lock, flags);
2296 sdp = sg_lookup_dev(dev);
2297 if (!sdp)
2298 sdp = ERR_PTR(-ENXIO);
2299 else if (atomic_read(&sdp->detaching)) {
2300 /* If sdp->detaching, then the refcount may already be 0, in
2301 * which case it would be a bug to do kref_get().
2302 */
2303 sdp = ERR_PTR(-ENODEV);
2304 } else
2305 kref_get(&sdp->d_ref);
2306 read_unlock_irqrestore(&sg_index_lock, flags);
2307
2308 return sdp;
2309 }
2310
2311 #ifdef CONFIG_SCSI_PROC_FS
2312 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2313
2314 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2315 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2316 size_t count, loff_t *off);
2317 static const struct proc_ops adio_proc_ops = {
2318 .proc_open = sg_proc_single_open_adio,
2319 .proc_read = seq_read,
2320 .proc_lseek = seq_lseek,
2321 .proc_write = sg_proc_write_adio,
2322 .proc_release = single_release,
2323 };
2324
2325 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2326 static ssize_t sg_proc_write_dressz(struct file *filp,
2327 const char __user *buffer, size_t count, loff_t *off);
2328 static const struct proc_ops dressz_proc_ops = {
2329 .proc_open = sg_proc_single_open_dressz,
2330 .proc_read = seq_read,
2331 .proc_lseek = seq_lseek,
2332 .proc_write = sg_proc_write_dressz,
2333 .proc_release = single_release,
2334 };
2335
2336 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2337 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2338 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2339 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2340 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2341 static void dev_seq_stop(struct seq_file *s, void *v);
2342 static const struct seq_operations dev_seq_ops = {
2343 .start = dev_seq_start,
2344 .next = dev_seq_next,
2345 .stop = dev_seq_stop,
2346 .show = sg_proc_seq_show_dev,
2347 };
2348
2349 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2350 static const struct seq_operations devstrs_seq_ops = {
2351 .start = dev_seq_start,
2352 .next = dev_seq_next,
2353 .stop = dev_seq_stop,
2354 .show = sg_proc_seq_show_devstrs,
2355 };
2356
2357 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2358 static const struct seq_operations debug_seq_ops = {
2359 .start = dev_seq_start,
2360 .next = dev_seq_next,
2361 .stop = dev_seq_stop,
2362 .show = sg_proc_seq_show_debug,
2363 };
2364
2365 static int
2366 sg_proc_init(void)
2367 {
2368 struct proc_dir_entry *p;
2369
2370 p = proc_mkdir("scsi/sg", NULL);
2371 if (!p)
2372 return 1;
2373
2374 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);
2375 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2376 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);
2377 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2378 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2379 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2380 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2381 return 0;
2382 }
2383
2384
2385 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2386 {
2387 seq_printf(s, "%d\n", *((int *)s->private));
2388 return 0;
2389 }
2390
2391 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2392 {
2393 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2394 }
2395
2396 static ssize_t
2397 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2398 size_t count, loff_t *off)
2399 {
2400 int err;
2401 unsigned long num;
2402
2403 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2404 return -EACCES;
2405 err = kstrtoul_from_user(buffer, count, 0, &num);
2406 if (err)
2407 return err;
2408 sg_allow_dio = num ? 1 : 0;
2409 return count;
2410 }
2411
2412 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2413 {
2414 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2415 }
2416
2417 static ssize_t
2418 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2419 size_t count, loff_t *off)
2420 {
2421 int err;
2422 unsigned long k = ULONG_MAX;
2423
2424 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2425 return -EACCES;
2426
2427 err = kstrtoul_from_user(buffer, count, 0, &k);
2428 if (err)
2429 return err;
2430 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2431 sg_big_buff = k;
2432 return count;
2433 }
2434 return -ERANGE;
2435 }
2436
2437 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2438 {
2439 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2440 sg_version_date);
2441 return 0;
2442 }
2443
2444 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2445 {
2446 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2447 return 0;
2448 }
2449
2450 struct sg_proc_deviter {
2451 loff_t index;
2452 size_t max;
2453 };
2454
2455 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2456 {
2457 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2458
2459 s->private = it;
2460 if (! it)
2461 return NULL;
2462
2463 it->index = *pos;
2464 it->max = sg_last_dev();
2465 if (it->index >= it->max)
2466 return NULL;
2467 return it;
2468 }
2469
2470 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2471 {
2472 struct sg_proc_deviter * it = s->private;
2473
2474 *pos = ++it->index;
2475 return (it->index < it->max) ? it : NULL;
2476 }
2477
2478 static void dev_seq_stop(struct seq_file *s, void *v)
2479 {
2480 kfree(s->private);
2481 }
2482
2483 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2484 {
2485 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2486 Sg_device *sdp;
2487 struct scsi_device *scsidp;
2488 unsigned long iflags;
2489
2490 read_lock_irqsave(&sg_index_lock, iflags);
2491 sdp = it ? sg_lookup_dev(it->index) : NULL;
2492 if ((NULL == sdp) || (NULL == sdp->device) ||
2493 (atomic_read(&sdp->detaching)))
2494 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2495 else {
2496 scsidp = sdp->device;
2497 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2498 scsidp->host->host_no, scsidp->channel,
2499 scsidp->id, scsidp->lun, (int) scsidp->type,
2500 1,
2501 (int) scsidp->queue_depth,
2502 (int) scsi_device_busy(scsidp),
2503 (int) scsi_device_online(scsidp));
2504 }
2505 read_unlock_irqrestore(&sg_index_lock, iflags);
2506 return 0;
2507 }
2508
2509 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2510 {
2511 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2512 Sg_device *sdp;
2513 struct scsi_device *scsidp;
2514 unsigned long iflags;
2515
2516 read_lock_irqsave(&sg_index_lock, iflags);
2517 sdp = it ? sg_lookup_dev(it->index) : NULL;
2518 scsidp = sdp ? sdp->device : NULL;
2519 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2520 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2521 scsidp->vendor, scsidp->model, scsidp->rev);
2522 else
2523 seq_puts(s, "<no active device>\n");
2524 read_unlock_irqrestore(&sg_index_lock, iflags);
2525 return 0;
2526 }
2527
2528 /* must be called while holding sg_index_lock */
2529 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2530 {
2531 int k, new_interface, blen, usg;
2532 Sg_request *srp;
2533 Sg_fd *fp;
2534 const sg_io_hdr_t *hp;
2535 const char * cp;
2536 unsigned int ms;
2537
2538 k = 0;
2539 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2540 k++;
2541 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2542 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2543 "(res)sgat=%d low_dma=%d\n", k,
2544 jiffies_to_msecs(fp->timeout),
2545 fp->reserve.bufflen,
2546 (int) fp->reserve.k_use_sg, 0);
2547 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2548 (int) fp->cmd_q, (int) fp->force_packid,
2549 (int) fp->keep_orphan);
2550 list_for_each_entry(srp, &fp->rq_list, entry) {
2551 hp = &srp->header;
2552 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2553 if (srp->res_used) {
2554 if (new_interface &&
2555 (SG_FLAG_MMAP_IO & hp->flags))
2556 cp = " mmap>> ";
2557 else
2558 cp = " rb>> ";
2559 } else {
2560 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2561 cp = " dio>> ";
2562 else
2563 cp = " ";
2564 }
2565 seq_puts(s, cp);
2566 blen = srp->data.bufflen;
2567 usg = srp->data.k_use_sg;
2568 seq_puts(s, srp->done ?
2569 ((1 == srp->done) ? "rcv:" : "fin:")
2570 : "act:");
2571 seq_printf(s, " id=%d blen=%d",
2572 srp->header.pack_id, blen);
2573 if (srp->done)
2574 seq_printf(s, " dur=%d", hp->duration);
2575 else {
2576 ms = jiffies_to_msecs(jiffies);
2577 seq_printf(s, " t_o/elap=%d/%d",
2578 (new_interface ? hp->timeout :
2579 jiffies_to_msecs(fp->timeout)),
2580 (ms > hp->duration ? ms - hp->duration : 0));
2581 }
2582 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2583 (int) srp->data.cmd_opcode);
2584 }
2585 if (list_empty(&fp->rq_list))
2586 seq_puts(s, " No requests active\n");
2587 read_unlock(&fp->rq_list_lock);
2588 }
2589 }
2590
2591 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2592 {
2593 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2594 Sg_device *sdp;
2595 unsigned long iflags;
2596
2597 if (it && (0 == it->index))
2598 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2599 (int)it->max, sg_big_buff);
2600
2601 read_lock_irqsave(&sg_index_lock, iflags);
2602 sdp = it ? sg_lookup_dev(it->index) : NULL;
2603 if (NULL == sdp)
2604 goto skip;
2605 read_lock(&sdp->sfd_lock);
2606 if (!list_empty(&sdp->sfds)) {
2607 seq_printf(s, " >>> device=%s ", sdp->name);
2608 if (atomic_read(&sdp->detaching))
2609 seq_puts(s, "detaching pending close ");
2610 else if (sdp->device) {
2611 struct scsi_device *scsidp = sdp->device;
2612
2613 seq_printf(s, "%d:%d:%d:%llu em=%d",
2614 scsidp->host->host_no,
2615 scsidp->channel, scsidp->id,
2616 scsidp->lun,
2617 scsidp->host->hostt->emulated);
2618 }
2619 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2620 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2621 sg_proc_debug_helper(s, sdp);
2622 }
2623 read_unlock(&sdp->sfd_lock);
2624 skip:
2625 read_unlock_irqrestore(&sg_index_lock, iflags);
2626 return 0;
2627 }
2628
2629 #endif /* CONFIG_SCSI_PROC_FS */
2630
2631 module_init(init_sg);
2632 module_exit(exit_sg);
Kernel DRM miscellaneous fixes and cross-tree changes