• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  *
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public Licens
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
17  *
18  */
19 #include <linux/kernel.h>
20 #include <linux/errno.h>
21 #include <linux/string.h>
22 #include <linux/module.h>
23 #include <linux/blkdev.h>
24 #include <linux/capability.h>
25 #include <linux/completion.h>
26 #include <linux/cdrom.h>
27 #include <linux/ratelimit.h>
28 #include <linux/slab.h>
29 #include <linux/times.h>
30 #include <linux/uio.h>
31 #include <asm/uaccess.h>
32 
33 #include <scsi/scsi.h>
34 #include <scsi/scsi_ioctl.h>
35 #include <scsi/scsi_cmnd.h>
36 
37 struct blk_cmd_filter {
38 	unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
39 	unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
40 };
41 
42 static struct blk_cmd_filter blk_default_cmd_filter;
43 
44 /* Command group 3 is reserved and should never be used.  */
45 const unsigned char scsi_command_size_tbl[8] =
46 {
47 	6, 10, 10, 12,
48 	16, 12, 10, 10
49 };
50 EXPORT_SYMBOL(scsi_command_size_tbl);
51 
52 #include <scsi/sg.h>
53 
sg_get_version(int __user * p)54 static int sg_get_version(int __user *p)
55 {
56 	static const int sg_version_num = 30527;
57 	return put_user(sg_version_num, p);
58 }
59 
scsi_get_idlun(struct request_queue * q,int __user * p)60 static int scsi_get_idlun(struct request_queue *q, int __user *p)
61 {
62 	return put_user(0, p);
63 }
64 
scsi_get_bus(struct request_queue * q,int __user * p)65 static int scsi_get_bus(struct request_queue *q, int __user *p)
66 {
67 	return put_user(0, p);
68 }
69 
sg_get_timeout(struct request_queue * q)70 static int sg_get_timeout(struct request_queue *q)
71 {
72 	return jiffies_to_clock_t(q->sg_timeout);
73 }
74 
sg_set_timeout(struct request_queue * q,int __user * p)75 static int sg_set_timeout(struct request_queue *q, int __user *p)
76 {
77 	int timeout, err = get_user(timeout, p);
78 
79 	if (!err)
80 		q->sg_timeout = clock_t_to_jiffies(timeout);
81 
82 	return err;
83 }
84 
max_sectors_bytes(struct request_queue * q)85 static int max_sectors_bytes(struct request_queue *q)
86 {
87 	unsigned int max_sectors = queue_max_sectors(q);
88 
89 	max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
90 
91 	return max_sectors << 9;
92 }
93 
sg_get_reserved_size(struct request_queue * q,int __user * p)94 static int sg_get_reserved_size(struct request_queue *q, int __user *p)
95 {
96 	int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q));
97 
98 	return put_user(val, p);
99 }
100 
sg_set_reserved_size(struct request_queue * q,int __user * p)101 static int sg_set_reserved_size(struct request_queue *q, int __user *p)
102 {
103 	int size, err = get_user(size, p);
104 
105 	if (err)
106 		return err;
107 
108 	if (size < 0)
109 		return -EINVAL;
110 
111 	q->sg_reserved_size = min(size, max_sectors_bytes(q));
112 	return 0;
113 }
114 
115 /*
116  * will always return that we are ATAPI even for a real SCSI drive, I'm not
117  * so sure this is worth doing anything about (why would you care??)
118  */
sg_emulated_host(struct request_queue * q,int __user * p)119 static int sg_emulated_host(struct request_queue *q, int __user *p)
120 {
121 	return put_user(1, p);
122 }
123 
blk_set_cmd_filter_defaults(struct blk_cmd_filter * filter)124 static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
125 {
126 	/* Basic read-only commands */
127 	__set_bit(TEST_UNIT_READY, filter->read_ok);
128 	__set_bit(REQUEST_SENSE, filter->read_ok);
129 	__set_bit(READ_6, filter->read_ok);
130 	__set_bit(READ_10, filter->read_ok);
131 	__set_bit(READ_12, filter->read_ok);
132 	__set_bit(READ_16, filter->read_ok);
133 	__set_bit(READ_BUFFER, filter->read_ok);
134 	__set_bit(READ_DEFECT_DATA, filter->read_ok);
135 	__set_bit(READ_CAPACITY, filter->read_ok);
136 	__set_bit(READ_LONG, filter->read_ok);
137 	__set_bit(INQUIRY, filter->read_ok);
138 	__set_bit(MODE_SENSE, filter->read_ok);
139 	__set_bit(MODE_SENSE_10, filter->read_ok);
140 	__set_bit(LOG_SENSE, filter->read_ok);
141 	__set_bit(START_STOP, filter->read_ok);
142 	__set_bit(GPCMD_VERIFY_10, filter->read_ok);
143 	__set_bit(VERIFY_16, filter->read_ok);
144 	__set_bit(REPORT_LUNS, filter->read_ok);
145 	__set_bit(SERVICE_ACTION_IN_16, filter->read_ok);
146 	__set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
147 	__set_bit(MAINTENANCE_IN, filter->read_ok);
148 	__set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
149 
150 	/* Audio CD commands */
151 	__set_bit(GPCMD_PLAY_CD, filter->read_ok);
152 	__set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
153 	__set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
154 	__set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
155 	__set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
156 
157 	/* CD/DVD data reading */
158 	__set_bit(GPCMD_READ_CD, filter->read_ok);
159 	__set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
160 	__set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
161 	__set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
162 	__set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
163 	__set_bit(GPCMD_READ_HEADER, filter->read_ok);
164 	__set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
165 	__set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
166 	__set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
167 	__set_bit(GPCMD_REPORT_KEY, filter->read_ok);
168 	__set_bit(GPCMD_SCAN, filter->read_ok);
169 	__set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
170 	__set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
171 	__set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
172 	__set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
173 	__set_bit(GPCMD_SEEK, filter->read_ok);
174 	__set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
175 
176 	/* Basic writing commands */
177 	__set_bit(WRITE_6, filter->write_ok);
178 	__set_bit(WRITE_10, filter->write_ok);
179 	__set_bit(WRITE_VERIFY, filter->write_ok);
180 	__set_bit(WRITE_12, filter->write_ok);
181 	__set_bit(WRITE_VERIFY_12, filter->write_ok);
182 	__set_bit(WRITE_16, filter->write_ok);
183 	__set_bit(WRITE_LONG, filter->write_ok);
184 	__set_bit(WRITE_LONG_2, filter->write_ok);
185 	__set_bit(WRITE_SAME, filter->write_ok);
186 	__set_bit(WRITE_SAME_16, filter->write_ok);
187 	__set_bit(WRITE_SAME_32, filter->write_ok);
188 	__set_bit(ERASE, filter->write_ok);
189 	__set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
190 	__set_bit(MODE_SELECT, filter->write_ok);
191 	__set_bit(LOG_SELECT, filter->write_ok);
192 	__set_bit(GPCMD_BLANK, filter->write_ok);
193 	__set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
194 	__set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
195 	__set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
196 	__set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
197 	__set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
198 	__set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
199 	__set_bit(GPCMD_SEND_EVENT, filter->write_ok);
200 	__set_bit(GPCMD_SEND_KEY, filter->write_ok);
201 	__set_bit(GPCMD_SEND_OPC, filter->write_ok);
202 	__set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
203 	__set_bit(GPCMD_SET_SPEED, filter->write_ok);
204 	__set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
205 	__set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
206 	__set_bit(GPCMD_SET_STREAMING, filter->write_ok);
207 	__set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
208 }
209 
blk_verify_command(unsigned char * cmd,fmode_t has_write_perm)210 int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
211 {
212 	struct blk_cmd_filter *filter = &blk_default_cmd_filter;
213 
214 	/* root can do any command. */
215 	if (capable(CAP_SYS_RAWIO))
216 		return 0;
217 
218 	/* Anybody who can open the device can do a read-safe command */
219 	if (test_bit(cmd[0], filter->read_ok))
220 		return 0;
221 
222 	/* Write-safe commands require a writable open */
223 	if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
224 		return 0;
225 
226 	return -EPERM;
227 }
228 EXPORT_SYMBOL(blk_verify_command);
229 
blk_fill_sghdr_rq(struct request_queue * q,struct request * rq,struct sg_io_hdr * hdr,fmode_t mode)230 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
231 			     struct sg_io_hdr *hdr, fmode_t mode)
232 {
233 	if (copy_from_user(rq->cmd, hdr->cmdp, hdr->cmd_len))
234 		return -EFAULT;
235 	if (blk_verify_command(rq->cmd, mode & FMODE_WRITE))
236 		return -EPERM;
237 
238 	/*
239 	 * fill in request structure
240 	 */
241 	rq->cmd_len = hdr->cmd_len;
242 
243 	rq->timeout = msecs_to_jiffies(hdr->timeout);
244 	if (!rq->timeout)
245 		rq->timeout = q->sg_timeout;
246 	if (!rq->timeout)
247 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
248 	if (rq->timeout < BLK_MIN_SG_TIMEOUT)
249 		rq->timeout = BLK_MIN_SG_TIMEOUT;
250 
251 	return 0;
252 }
253 
blk_complete_sghdr_rq(struct request * rq,struct sg_io_hdr * hdr,struct bio * bio)254 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
255 				 struct bio *bio)
256 {
257 	int r, ret = 0;
258 
259 	/*
260 	 * fill in all the output members
261 	 */
262 	hdr->status = rq->errors & 0xff;
263 	hdr->masked_status = status_byte(rq->errors);
264 	hdr->msg_status = msg_byte(rq->errors);
265 	hdr->host_status = host_byte(rq->errors);
266 	hdr->driver_status = driver_byte(rq->errors);
267 	hdr->info = 0;
268 	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
269 		hdr->info |= SG_INFO_CHECK;
270 	hdr->resid = rq->resid_len;
271 	hdr->sb_len_wr = 0;
272 
273 	if (rq->sense_len && hdr->sbp) {
274 		int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
275 
276 		if (!copy_to_user(hdr->sbp, rq->sense, len))
277 			hdr->sb_len_wr = len;
278 		else
279 			ret = -EFAULT;
280 	}
281 
282 	r = blk_rq_unmap_user(bio);
283 	if (!ret)
284 		ret = r;
285 
286 	return ret;
287 }
288 
sg_io(struct request_queue * q,struct gendisk * bd_disk,struct sg_io_hdr * hdr,fmode_t mode)289 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
290 		struct sg_io_hdr *hdr, fmode_t mode)
291 {
292 	unsigned long start_time;
293 	ssize_t ret = 0;
294 	int writing = 0;
295 	int at_head = 0;
296 	struct request *rq;
297 	char sense[SCSI_SENSE_BUFFERSIZE];
298 	struct bio *bio;
299 
300 	if (hdr->interface_id != 'S')
301 		return -EINVAL;
302 
303 	if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
304 		return -EIO;
305 
306 	if (hdr->dxfer_len)
307 		switch (hdr->dxfer_direction) {
308 		default:
309 			return -EINVAL;
310 		case SG_DXFER_TO_DEV:
311 			writing = 1;
312 			break;
313 		case SG_DXFER_TO_FROM_DEV:
314 		case SG_DXFER_FROM_DEV:
315 			break;
316 		}
317 	if (hdr->flags & SG_FLAG_Q_AT_HEAD)
318 		at_head = 1;
319 
320 	ret = -ENOMEM;
321 	rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
322 	if (IS_ERR(rq))
323 		return PTR_ERR(rq);
324 	blk_rq_set_block_pc(rq);
325 
326 	if (hdr->cmd_len > BLK_MAX_CDB) {
327 		rq->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
328 		if (!rq->cmd)
329 			goto out_put_request;
330 	}
331 
332 	ret = blk_fill_sghdr_rq(q, rq, hdr, mode);
333 	if (ret < 0)
334 		goto out_free_cdb;
335 
336 	ret = 0;
337 	if (hdr->iovec_count) {
338 		struct iov_iter i;
339 		struct iovec *iov = NULL;
340 
341 		ret = import_iovec(rq_data_dir(rq),
342 				   hdr->dxferp, hdr->iovec_count,
343 				   0, &iov, &i);
344 		if (ret < 0)
345 			goto out_free_cdb;
346 
347 		/* SG_IO howto says that the shorter of the two wins */
348 		iov_iter_truncate(&i, hdr->dxfer_len);
349 
350 		ret = blk_rq_map_user_iov(q, rq, NULL, &i, GFP_KERNEL);
351 		kfree(iov);
352 	} else if (hdr->dxfer_len)
353 		ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
354 				      GFP_KERNEL);
355 
356 	if (ret)
357 		goto out_free_cdb;
358 
359 	bio = rq->bio;
360 	memset(sense, 0, sizeof(sense));
361 	rq->sense = sense;
362 	rq->sense_len = 0;
363 	rq->retries = 0;
364 
365 	start_time = jiffies;
366 
367 	/* ignore return value. All information is passed back to caller
368 	 * (if he doesn't check that is his problem).
369 	 * N.B. a non-zero SCSI status is _not_ necessarily an error.
370 	 */
371 	blk_execute_rq(q, bd_disk, rq, at_head);
372 
373 	hdr->duration = jiffies_to_msecs(jiffies - start_time);
374 
375 	ret = blk_complete_sghdr_rq(rq, hdr, bio);
376 
377 out_free_cdb:
378 	if (rq->cmd != rq->__cmd)
379 		kfree(rq->cmd);
380 out_put_request:
381 	blk_put_request(rq);
382 	return ret;
383 }
384 
385 /**
386  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
387  * @file:	file this ioctl operates on (optional)
388  * @q:		request queue to send scsi commands down
389  * @disk:	gendisk to operate on (option)
390  * @sic:	userspace structure describing the command to perform
391  *
392  * Send down the scsi command described by @sic to the device below
393  * the request queue @q.  If @file is non-NULL it's used to perform
394  * fine-grained permission checks that allow users to send down
395  * non-destructive SCSI commands.  If the caller has a struct gendisk
396  * available it should be passed in as @disk to allow the low level
397  * driver to use the information contained in it.  A non-NULL @disk
398  * is only allowed if the caller knows that the low level driver doesn't
399  * need it (e.g. in the scsi subsystem).
400  *
401  * Notes:
402  *   -  This interface is deprecated - users should use the SG_IO
403  *      interface instead, as this is a more flexible approach to
404  *      performing SCSI commands on a device.
405  *   -  The SCSI command length is determined by examining the 1st byte
406  *      of the given command. There is no way to override this.
407  *   -  Data transfers are limited to PAGE_SIZE
408  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
409  *      accommodate the sense buffer when an error occurs.
410  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
411  *      old code will not be surprised.
412  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
413  *      a negative return and the Unix error code in 'errno'.
414  *      If the SCSI command succeeds then 0 is returned.
415  *      Positive numbers returned are the compacted SCSI error codes (4
416  *      bytes in one int) where the lowest byte is the SCSI status.
417  */
418 #define OMAX_SB_LEN 16          /* For backward compatibility */
sg_scsi_ioctl(struct request_queue * q,struct gendisk * disk,fmode_t mode,struct scsi_ioctl_command __user * sic)419 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
420 		struct scsi_ioctl_command __user *sic)
421 {
422 	struct request *rq;
423 	int err;
424 	unsigned int in_len, out_len, bytes, opcode, cmdlen;
425 	char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
426 
427 	if (!sic)
428 		return -EINVAL;
429 
430 	/*
431 	 * get in an out lengths, verify they don't exceed a page worth of data
432 	 */
433 	if (get_user(in_len, &sic->inlen))
434 		return -EFAULT;
435 	if (get_user(out_len, &sic->outlen))
436 		return -EFAULT;
437 	if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
438 		return -EINVAL;
439 	if (get_user(opcode, sic->data))
440 		return -EFAULT;
441 
442 	bytes = max(in_len, out_len);
443 	if (bytes) {
444 		buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
445 		if (!buffer)
446 			return -ENOMEM;
447 
448 	}
449 
450 	rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_RECLAIM);
451 	if (IS_ERR(rq)) {
452 		err = PTR_ERR(rq);
453 		goto error_free_buffer;
454 	}
455 	blk_rq_set_block_pc(rq);
456 
457 	cmdlen = COMMAND_SIZE(opcode);
458 
459 	/*
460 	 * get command and data to send to device, if any
461 	 */
462 	err = -EFAULT;
463 	rq->cmd_len = cmdlen;
464 	if (copy_from_user(rq->cmd, sic->data, cmdlen))
465 		goto error;
466 
467 	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
468 		goto error;
469 
470 	err = blk_verify_command(rq->cmd, mode & FMODE_WRITE);
471 	if (err)
472 		goto error;
473 
474 	/* default.  possible overriden later */
475 	rq->retries = 5;
476 
477 	switch (opcode) {
478 	case SEND_DIAGNOSTIC:
479 	case FORMAT_UNIT:
480 		rq->timeout = FORMAT_UNIT_TIMEOUT;
481 		rq->retries = 1;
482 		break;
483 	case START_STOP:
484 		rq->timeout = START_STOP_TIMEOUT;
485 		break;
486 	case MOVE_MEDIUM:
487 		rq->timeout = MOVE_MEDIUM_TIMEOUT;
488 		break;
489 	case READ_ELEMENT_STATUS:
490 		rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
491 		break;
492 	case READ_DEFECT_DATA:
493 		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
494 		rq->retries = 1;
495 		break;
496 	default:
497 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
498 		break;
499 	}
500 
501 	if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_RECLAIM)) {
502 		err = DRIVER_ERROR << 24;
503 		goto error;
504 	}
505 
506 	memset(sense, 0, sizeof(sense));
507 	rq->sense = sense;
508 	rq->sense_len = 0;
509 
510 	blk_execute_rq(q, disk, rq, 0);
511 
512 	err = rq->errors & 0xff;	/* only 8 bit SCSI status */
513 	if (err) {
514 		if (rq->sense_len && rq->sense) {
515 			bytes = (OMAX_SB_LEN > rq->sense_len) ?
516 				rq->sense_len : OMAX_SB_LEN;
517 			if (copy_to_user(sic->data, rq->sense, bytes))
518 				err = -EFAULT;
519 		}
520 	} else {
521 		if (copy_to_user(sic->data, buffer, out_len))
522 			err = -EFAULT;
523 	}
524 
525 error:
526 	blk_put_request(rq);
527 
528 error_free_buffer:
529 	kfree(buffer);
530 
531 	return err;
532 }
533 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
534 
535 /* Send basic block requests */
__blk_send_generic(struct request_queue * q,struct gendisk * bd_disk,int cmd,int data)536 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
537 			      int cmd, int data)
538 {
539 	struct request *rq;
540 	int err;
541 
542 	rq = blk_get_request(q, WRITE, __GFP_RECLAIM);
543 	if (IS_ERR(rq))
544 		return PTR_ERR(rq);
545 	blk_rq_set_block_pc(rq);
546 	rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
547 	rq->cmd[0] = cmd;
548 	rq->cmd[4] = data;
549 	rq->cmd_len = 6;
550 	err = blk_execute_rq(q, bd_disk, rq, 0);
551 	blk_put_request(rq);
552 
553 	return err;
554 }
555 
blk_send_start_stop(struct request_queue * q,struct gendisk * bd_disk,int data)556 static inline int blk_send_start_stop(struct request_queue *q,
557 				      struct gendisk *bd_disk, int data)
558 {
559 	return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
560 }
561 
scsi_cmd_ioctl(struct request_queue * q,struct gendisk * bd_disk,fmode_t mode,unsigned int cmd,void __user * arg)562 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
563 		   unsigned int cmd, void __user *arg)
564 {
565 	int err;
566 
567 	if (!q)
568 		return -ENXIO;
569 
570 	switch (cmd) {
571 		/*
572 		 * new sgv3 interface
573 		 */
574 		case SG_GET_VERSION_NUM:
575 			err = sg_get_version(arg);
576 			break;
577 		case SCSI_IOCTL_GET_IDLUN:
578 			err = scsi_get_idlun(q, arg);
579 			break;
580 		case SCSI_IOCTL_GET_BUS_NUMBER:
581 			err = scsi_get_bus(q, arg);
582 			break;
583 		case SG_SET_TIMEOUT:
584 			err = sg_set_timeout(q, arg);
585 			break;
586 		case SG_GET_TIMEOUT:
587 			err = sg_get_timeout(q);
588 			break;
589 		case SG_GET_RESERVED_SIZE:
590 			err = sg_get_reserved_size(q, arg);
591 			break;
592 		case SG_SET_RESERVED_SIZE:
593 			err = sg_set_reserved_size(q, arg);
594 			break;
595 		case SG_EMULATED_HOST:
596 			err = sg_emulated_host(q, arg);
597 			break;
598 		case SG_IO: {
599 			struct sg_io_hdr hdr;
600 
601 			err = -EFAULT;
602 			if (copy_from_user(&hdr, arg, sizeof(hdr)))
603 				break;
604 			err = sg_io(q, bd_disk, &hdr, mode);
605 			if (err == -EFAULT)
606 				break;
607 
608 			if (copy_to_user(arg, &hdr, sizeof(hdr)))
609 				err = -EFAULT;
610 			break;
611 		}
612 		case CDROM_SEND_PACKET: {
613 			struct cdrom_generic_command cgc;
614 			struct sg_io_hdr hdr;
615 
616 			err = -EFAULT;
617 			if (copy_from_user(&cgc, arg, sizeof(cgc)))
618 				break;
619 			cgc.timeout = clock_t_to_jiffies(cgc.timeout);
620 			memset(&hdr, 0, sizeof(hdr));
621 			hdr.interface_id = 'S';
622 			hdr.cmd_len = sizeof(cgc.cmd);
623 			hdr.dxfer_len = cgc.buflen;
624 			err = 0;
625 			switch (cgc.data_direction) {
626 				case CGC_DATA_UNKNOWN:
627 					hdr.dxfer_direction = SG_DXFER_UNKNOWN;
628 					break;
629 				case CGC_DATA_WRITE:
630 					hdr.dxfer_direction = SG_DXFER_TO_DEV;
631 					break;
632 				case CGC_DATA_READ:
633 					hdr.dxfer_direction = SG_DXFER_FROM_DEV;
634 					break;
635 				case CGC_DATA_NONE:
636 					hdr.dxfer_direction = SG_DXFER_NONE;
637 					break;
638 				default:
639 					err = -EINVAL;
640 			}
641 			if (err)
642 				break;
643 
644 			hdr.dxferp = cgc.buffer;
645 			hdr.sbp = cgc.sense;
646 			if (hdr.sbp)
647 				hdr.mx_sb_len = sizeof(struct request_sense);
648 			hdr.timeout = jiffies_to_msecs(cgc.timeout);
649 			hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
650 			hdr.cmd_len = sizeof(cgc.cmd);
651 
652 			err = sg_io(q, bd_disk, &hdr, mode);
653 			if (err == -EFAULT)
654 				break;
655 
656 			if (hdr.status)
657 				err = -EIO;
658 
659 			cgc.stat = err;
660 			cgc.buflen = hdr.resid;
661 			if (copy_to_user(arg, &cgc, sizeof(cgc)))
662 				err = -EFAULT;
663 
664 			break;
665 		}
666 
667 		/*
668 		 * old junk scsi send command ioctl
669 		 */
670 		case SCSI_IOCTL_SEND_COMMAND:
671 			printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
672 			err = -EINVAL;
673 			if (!arg)
674 				break;
675 
676 			err = sg_scsi_ioctl(q, bd_disk, mode, arg);
677 			break;
678 		case CDROMCLOSETRAY:
679 			err = blk_send_start_stop(q, bd_disk, 0x03);
680 			break;
681 		case CDROMEJECT:
682 			err = blk_send_start_stop(q, bd_disk, 0x02);
683 			break;
684 		default:
685 			err = -ENOTTY;
686 	}
687 
688 	return err;
689 }
690 EXPORT_SYMBOL(scsi_cmd_ioctl);
691 
scsi_verify_blk_ioctl(struct block_device * bd,unsigned int cmd)692 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
693 {
694 	if (bd && bd == bd->bd_contains)
695 		return 0;
696 
697 	/* Actually none of these is particularly useful on a partition,
698 	 * but they are safe.
699 	 */
700 	switch (cmd) {
701 	case SCSI_IOCTL_GET_IDLUN:
702 	case SCSI_IOCTL_GET_BUS_NUMBER:
703 	case SCSI_IOCTL_GET_PCI:
704 	case SCSI_IOCTL_PROBE_HOST:
705 	case SG_GET_VERSION_NUM:
706 	case SG_SET_TIMEOUT:
707 	case SG_GET_TIMEOUT:
708 	case SG_GET_RESERVED_SIZE:
709 	case SG_SET_RESERVED_SIZE:
710 	case SG_EMULATED_HOST:
711 		return 0;
712 	case CDROM_GET_CAPABILITY:
713 		/* Keep this until we remove the printk below.  udev sends it
714 		 * and we do not want to spam dmesg about it.   CD-ROMs do
715 		 * not have partitions, so we get here only for disks.
716 		 */
717 		return -ENOIOCTLCMD;
718 	default:
719 		break;
720 	}
721 
722 	if (capable(CAP_SYS_RAWIO))
723 		return 0;
724 
725 	/* In particular, rule out all resets and host-specific ioctls.  */
726 	printk_ratelimited(KERN_WARNING
727 			   "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
728 
729 	return -ENOIOCTLCMD;
730 }
731 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
732 
scsi_cmd_blk_ioctl(struct block_device * bd,fmode_t mode,unsigned int cmd,void __user * arg)733 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
734 		       unsigned int cmd, void __user *arg)
735 {
736 	int ret;
737 
738 	ret = scsi_verify_blk_ioctl(bd, cmd);
739 	if (ret < 0)
740 		return ret;
741 
742 	return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
743 }
744 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
745 
blk_scsi_ioctl_init(void)746 static int __init blk_scsi_ioctl_init(void)
747 {
748 	blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
749 	return 0;
750 }
751 fs_initcall(blk_scsi_ioctl_init);
752