xref: /linux/drivers/scsi/scsi_ioctl.c (revision ea8a163e02d6925773129e2dd86e419e491b791d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Changes:
4  * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000
5  * - get rid of some verify_areas and use __copy*user and __get/put_user
6  *   for the ones that remain
7  */
8 #include <linux/module.h>
9 #include <linux/blkdev.h>
10 #include <linux/interrupt.h>
11 #include <linux/errno.h>
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/mm.h>
15 #include <linux/string.h>
16 #include <linux/uaccess.h>
17 #include <linux/cdrom.h>
18 
19 #include <scsi/scsi.h>
20 #include <scsi/scsi_cmnd.h>
21 #include <scsi/scsi_device.h>
22 #include <scsi/scsi_eh.h>
23 #include <scsi/scsi_host.h>
24 #include <scsi/scsi_ioctl.h>
25 #include <scsi/sg.h>
26 #include <scsi/scsi_dbg.h>
27 
28 #include "scsi_logging.h"
29 
30 #define NORMAL_RETRIES			5
31 #define IOCTL_NORMAL_TIMEOUT			(10 * HZ)
32 
33 #define MAX_BUF PAGE_SIZE
34 
35 /**
36  * ioctl_probe  --  return host identification
37  * @host:	host to identify
38  * @buffer:	userspace buffer for identification
39  *
40  * Return an identifying string at @buffer, if @buffer is non-NULL, filling
41  * to the length stored at * (int *) @buffer.
42  */
43 static int ioctl_probe(struct Scsi_Host *host, void __user *buffer)
44 {
45 	unsigned int len, slen;
46 	const char *string;
47 
48 	if (buffer) {
49 		if (get_user(len, (unsigned int __user *) buffer))
50 			return -EFAULT;
51 
52 		if (host->hostt->info)
53 			string = host->hostt->info(host);
54 		else
55 			string = host->hostt->name;
56 		if (string) {
57 			slen = strlen(string);
58 			if (len > slen)
59 				len = slen + 1;
60 			if (copy_to_user(buffer, string, len))
61 				return -EFAULT;
62 		}
63 	}
64 	return 1;
65 }
66 
67 static int ioctl_internal_command(struct scsi_device *sdev, char *cmd,
68 				  int timeout, int retries)
69 {
70 	int result;
71 	struct scsi_sense_hdr sshdr;
72 
73 	SCSI_LOG_IOCTL(1, sdev_printk(KERN_INFO, sdev,
74 				      "Trying ioctl with scsi command %d\n", *cmd));
75 
76 	result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0,
77 				  &sshdr, timeout, retries, NULL);
78 
79 	SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
80 				      "Ioctl returned  0x%x\n", result));
81 
82 	if (result < 0)
83 		goto out;
84 	if (scsi_sense_valid(&sshdr)) {
85 		switch (sshdr.sense_key) {
86 		case ILLEGAL_REQUEST:
87 			if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
88 				sdev->lockable = 0;
89 			else
90 				sdev_printk(KERN_INFO, sdev,
91 					    "ioctl_internal_command: "
92 					    "ILLEGAL REQUEST "
93 					    "asc=0x%x ascq=0x%x\n",
94 					    sshdr.asc, sshdr.ascq);
95 			break;
96 		case NOT_READY:	/* This happens if there is no disc in drive */
97 			if (sdev->removable)
98 				break;
99 			fallthrough;
100 		case UNIT_ATTENTION:
101 			if (sdev->removable) {
102 				sdev->changed = 1;
103 				result = 0;	/* This is no longer considered an error */
104 				break;
105 			}
106 			fallthrough;	/* for non-removable media */
107 		default:
108 			sdev_printk(KERN_INFO, sdev,
109 				    "ioctl_internal_command return code = %x\n",
110 				    result);
111 			scsi_print_sense_hdr(sdev, NULL, &sshdr);
112 			break;
113 		}
114 	}
115 out:
116 	SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
117 				      "IOCTL Releasing command\n"));
118 	return result;
119 }
120 
121 int scsi_set_medium_removal(struct scsi_device *sdev, char state)
122 {
123 	char scsi_cmd[MAX_COMMAND_SIZE];
124 	int ret;
125 
126 	if (!sdev->removable || !sdev->lockable)
127 	       return 0;
128 
129 	scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
130 	scsi_cmd[1] = 0;
131 	scsi_cmd[2] = 0;
132 	scsi_cmd[3] = 0;
133 	scsi_cmd[4] = state;
134 	scsi_cmd[5] = 0;
135 
136 	ret = ioctl_internal_command(sdev, scsi_cmd,
137 			IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
138 	if (ret == 0)
139 		sdev->locked = (state == SCSI_REMOVAL_PREVENT);
140 	return ret;
141 }
142 EXPORT_SYMBOL(scsi_set_medium_removal);
143 
144 /*
145  * The scsi_ioctl_get_pci() function places into arg the value
146  * pci_dev::slot_name (8 characters) for the PCI device (if any).
147  * Returns: 0 on success
148  *          -ENXIO if there isn't a PCI device pointer
149  *                 (could be because the SCSI driver hasn't been
150  *                  updated yet, or because it isn't a SCSI
151  *                  device)
152  *          any copy_to_user() error on failure there
153  */
154 static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg)
155 {
156 	struct device *dev = scsi_get_device(sdev->host);
157 	const char *name;
158 
159         if (!dev)
160 		return -ENXIO;
161 
162 	name = dev_name(dev);
163 
164 	/* compatibility with old ioctl which only returned
165 	 * 20 characters */
166         return copy_to_user(arg, name, min(strlen(name), (size_t)20))
167 		? -EFAULT: 0;
168 }
169 
170 static int sg_get_version(int __user *p)
171 {
172 	static const int sg_version_num = 30527;
173 	return put_user(sg_version_num, p);
174 }
175 
176 static int sg_set_timeout(struct scsi_device *sdev, int __user *p)
177 {
178 	int timeout, err = get_user(timeout, p);
179 
180 	if (!err)
181 		sdev->sg_timeout = clock_t_to_jiffies(timeout);
182 
183 	return err;
184 }
185 
186 static int sg_get_reserved_size(struct scsi_device *sdev, int __user *p)
187 {
188 	int val = min(sdev->sg_reserved_size,
189 		      queue_max_bytes(sdev->request_queue));
190 
191 	return put_user(val, p);
192 }
193 
194 static int sg_set_reserved_size(struct scsi_device *sdev, int __user *p)
195 {
196 	int size, err = get_user(size, p);
197 
198 	if (err)
199 		return err;
200 
201 	if (size < 0)
202 		return -EINVAL;
203 
204 	sdev->sg_reserved_size = min_t(unsigned int, size,
205 				       queue_max_bytes(sdev->request_queue));
206 	return 0;
207 }
208 
209 /*
210  * will always return that we are ATAPI even for a real SCSI drive, I'm not
211  * so sure this is worth doing anything about (why would you care??)
212  */
213 static int sg_emulated_host(struct request_queue *q, int __user *p)
214 {
215 	return put_user(1, p);
216 }
217 
218 static int scsi_get_idlun(struct scsi_device *sdev, void __user *argp)
219 {
220 	struct scsi_idlun v = {
221 		.dev_id = (sdev->id & 0xff) +
222 			((sdev->lun & 0xff) << 8) +
223 			((sdev->channel & 0xff) << 16) +
224 			((sdev->host->host_no & 0xff) << 24),
225 		.host_unique_id = sdev->host->unique_id
226 	};
227 	if (copy_to_user(argp, &v, sizeof(struct scsi_idlun)))
228 		return -EFAULT;
229 	return 0;
230 }
231 
232 static int scsi_send_start_stop(struct scsi_device *sdev, int data)
233 {
234 	u8 cdb[MAX_COMMAND_SIZE] = { };
235 
236 	cdb[0] = START_STOP;
237 	cdb[4] = data;
238 	return ioctl_internal_command(sdev, cdb, START_STOP_TIMEOUT,
239 				      NORMAL_RETRIES);
240 }
241 
242 /*
243  * Check if the given command is allowed.
244  *
245  * Only a subset of commands are allowed for unprivileged users. Commands used
246  * to format the media, update the firmware, etc. are not permitted.
247  */
248 bool scsi_cmd_allowed(unsigned char *cmd, fmode_t mode)
249 {
250 	/* root can do any command. */
251 	if (capable(CAP_SYS_RAWIO))
252 		return true;
253 
254 	/* Anybody who can open the device can do a read-safe command */
255 	switch (cmd[0]) {
256 	/* Basic read-only commands */
257 	case TEST_UNIT_READY:
258 	case REQUEST_SENSE:
259 	case READ_6:
260 	case READ_10:
261 	case READ_12:
262 	case READ_16:
263 	case READ_BUFFER:
264 	case READ_DEFECT_DATA:
265 	case READ_CAPACITY: /* also GPCMD_READ_CDVD_CAPACITY */
266 	case READ_LONG:
267 	case INQUIRY:
268 	case MODE_SENSE:
269 	case MODE_SENSE_10:
270 	case LOG_SENSE:
271 	case START_STOP:
272 	case GPCMD_VERIFY_10:
273 	case VERIFY_16:
274 	case REPORT_LUNS:
275 	case SERVICE_ACTION_IN_16:
276 	case RECEIVE_DIAGNOSTIC:
277 	case MAINTENANCE_IN: /* also GPCMD_SEND_KEY, which is a write command */
278 	case GPCMD_READ_BUFFER_CAPACITY:
279 	/* Audio CD commands */
280 	case GPCMD_PLAY_CD:
281 	case GPCMD_PLAY_AUDIO_10:
282 	case GPCMD_PLAY_AUDIO_MSF:
283 	case GPCMD_PLAY_AUDIO_TI:
284 	case GPCMD_PAUSE_RESUME:
285 	/* CD/DVD data reading */
286 	case GPCMD_READ_CD:
287 	case GPCMD_READ_CD_MSF:
288 	case GPCMD_READ_DISC_INFO:
289 	case GPCMD_READ_DVD_STRUCTURE:
290 	case GPCMD_READ_HEADER:
291 	case GPCMD_READ_TRACK_RZONE_INFO:
292 	case GPCMD_READ_SUBCHANNEL:
293 	case GPCMD_READ_TOC_PMA_ATIP:
294 	case GPCMD_REPORT_KEY:
295 	case GPCMD_SCAN:
296 	case GPCMD_GET_CONFIGURATION:
297 	case GPCMD_READ_FORMAT_CAPACITIES:
298 	case GPCMD_GET_EVENT_STATUS_NOTIFICATION:
299 	case GPCMD_GET_PERFORMANCE:
300 	case GPCMD_SEEK:
301 	case GPCMD_STOP_PLAY_SCAN:
302 	/* ZBC */
303 	case ZBC_IN:
304 		return true;
305 	/* Basic writing commands */
306 	case WRITE_6:
307 	case WRITE_10:
308 	case WRITE_VERIFY:
309 	case WRITE_12:
310 	case WRITE_VERIFY_12:
311 	case WRITE_16:
312 	case WRITE_LONG:
313 	case WRITE_LONG_2:
314 	case WRITE_SAME:
315 	case WRITE_SAME_16:
316 	case WRITE_SAME_32:
317 	case ERASE:
318 	case GPCMD_MODE_SELECT_10:
319 	case MODE_SELECT:
320 	case LOG_SELECT:
321 	case GPCMD_BLANK:
322 	case GPCMD_CLOSE_TRACK:
323 	case GPCMD_FLUSH_CACHE:
324 	case GPCMD_FORMAT_UNIT:
325 	case GPCMD_REPAIR_RZONE_TRACK:
326 	case GPCMD_RESERVE_RZONE_TRACK:
327 	case GPCMD_SEND_DVD_STRUCTURE:
328 	case GPCMD_SEND_EVENT:
329 	case GPCMD_SEND_OPC:
330 	case GPCMD_SEND_CUE_SHEET:
331 	case GPCMD_SET_SPEED:
332 	case GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
333 	case GPCMD_LOAD_UNLOAD:
334 	case GPCMD_SET_STREAMING:
335 	case GPCMD_SET_READ_AHEAD:
336 	/* ZBC */
337 	case ZBC_OUT:
338 		return (mode & FMODE_WRITE);
339 	default:
340 		return false;
341 	}
342 }
343 EXPORT_SYMBOL(scsi_cmd_allowed);
344 
345 static int scsi_fill_sghdr_rq(struct scsi_device *sdev, struct request *rq,
346 		struct sg_io_hdr *hdr, fmode_t mode)
347 {
348 	struct scsi_request *req = scsi_req(rq);
349 
350 	if (hdr->cmd_len < 6)
351 		return -EMSGSIZE;
352 	if (copy_from_user(req->cmd, hdr->cmdp, hdr->cmd_len))
353 		return -EFAULT;
354 	if (!scsi_cmd_allowed(req->cmd, mode))
355 		return -EPERM;
356 
357 	/*
358 	 * fill in request structure
359 	 */
360 	req->cmd_len = hdr->cmd_len;
361 
362 	rq->timeout = msecs_to_jiffies(hdr->timeout);
363 	if (!rq->timeout)
364 		rq->timeout = sdev->sg_timeout;
365 	if (!rq->timeout)
366 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
367 	if (rq->timeout < BLK_MIN_SG_TIMEOUT)
368 		rq->timeout = BLK_MIN_SG_TIMEOUT;
369 
370 	return 0;
371 }
372 
373 static int scsi_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
374 		struct bio *bio)
375 {
376 	struct scsi_request *req = scsi_req(rq);
377 	int r, ret = 0;
378 
379 	/*
380 	 * fill in all the output members
381 	 */
382 	hdr->status = req->result & 0xff;
383 	hdr->masked_status = status_byte(req->result);
384 	hdr->msg_status = COMMAND_COMPLETE;
385 	hdr->host_status = host_byte(req->result);
386 	hdr->driver_status = 0;
387 	if (scsi_status_is_check_condition(hdr->status))
388 		hdr->driver_status = DRIVER_SENSE;
389 	hdr->info = 0;
390 	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
391 		hdr->info |= SG_INFO_CHECK;
392 	hdr->resid = req->resid_len;
393 	hdr->sb_len_wr = 0;
394 
395 	if (req->sense_len && hdr->sbp) {
396 		int len = min((unsigned int) hdr->mx_sb_len, req->sense_len);
397 
398 		if (!copy_to_user(hdr->sbp, req->sense, len))
399 			hdr->sb_len_wr = len;
400 		else
401 			ret = -EFAULT;
402 	}
403 
404 	r = blk_rq_unmap_user(bio);
405 	if (!ret)
406 		ret = r;
407 
408 	return ret;
409 }
410 
411 static int sg_io(struct scsi_device *sdev, struct gendisk *disk,
412 		struct sg_io_hdr *hdr, fmode_t mode)
413 {
414 	unsigned long start_time;
415 	ssize_t ret = 0;
416 	int writing = 0;
417 	int at_head = 0;
418 	struct request *rq;
419 	struct scsi_request *req;
420 	struct bio *bio;
421 
422 	if (hdr->interface_id != 'S')
423 		return -EINVAL;
424 
425 	if (hdr->dxfer_len > (queue_max_hw_sectors(sdev->request_queue) << 9))
426 		return -EIO;
427 
428 	if (hdr->dxfer_len)
429 		switch (hdr->dxfer_direction) {
430 		default:
431 			return -EINVAL;
432 		case SG_DXFER_TO_DEV:
433 			writing = 1;
434 			break;
435 		case SG_DXFER_TO_FROM_DEV:
436 		case SG_DXFER_FROM_DEV:
437 			break;
438 		}
439 	if (hdr->flags & SG_FLAG_Q_AT_HEAD)
440 		at_head = 1;
441 
442 	ret = -ENOMEM;
443 	rq = scsi_alloc_request(sdev->request_queue, writing ?
444 			     REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
445 	if (IS_ERR(rq))
446 		return PTR_ERR(rq);
447 	req = scsi_req(rq);
448 
449 	if (hdr->cmd_len > BLK_MAX_CDB) {
450 		req->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
451 		if (!req->cmd)
452 			goto out_put_request;
453 	}
454 
455 	ret = scsi_fill_sghdr_rq(sdev, rq, hdr, mode);
456 	if (ret < 0)
457 		goto out_free_cdb;
458 
459 	ret = 0;
460 	if (hdr->iovec_count) {
461 		struct iov_iter i;
462 		struct iovec *iov = NULL;
463 
464 		ret = import_iovec(rq_data_dir(rq), hdr->dxferp,
465 				   hdr->iovec_count, 0, &iov, &i);
466 		if (ret < 0)
467 			goto out_free_cdb;
468 
469 		/* SG_IO howto says that the shorter of the two wins */
470 		iov_iter_truncate(&i, hdr->dxfer_len);
471 
472 		ret = blk_rq_map_user_iov(rq->q, rq, NULL, &i, GFP_KERNEL);
473 		kfree(iov);
474 	} else if (hdr->dxfer_len)
475 		ret = blk_rq_map_user(rq->q, rq, NULL, hdr->dxferp,
476 				      hdr->dxfer_len, GFP_KERNEL);
477 
478 	if (ret)
479 		goto out_free_cdb;
480 
481 	bio = rq->bio;
482 	req->retries = 0;
483 
484 	start_time = jiffies;
485 
486 	blk_execute_rq(disk, rq, at_head);
487 
488 	hdr->duration = jiffies_to_msecs(jiffies - start_time);
489 
490 	ret = scsi_complete_sghdr_rq(rq, hdr, bio);
491 
492 out_free_cdb:
493 	scsi_req_free_cmd(req);
494 out_put_request:
495 	blk_mq_free_request(rq);
496 	return ret;
497 }
498 
499 /**
500  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
501  * @q:		request queue to send scsi commands down
502  * @disk:	gendisk to operate on (option)
503  * @mode:	mode used to open the file through which the ioctl has been
504  *		submitted
505  * @sic:	userspace structure describing the command to perform
506  *
507  * Send down the scsi command described by @sic to the device below
508  * the request queue @q.  If @file is non-NULL it's used to perform
509  * fine-grained permission checks that allow users to send down
510  * non-destructive SCSI commands.  If the caller has a struct gendisk
511  * available it should be passed in as @disk to allow the low level
512  * driver to use the information contained in it.  A non-NULL @disk
513  * is only allowed if the caller knows that the low level driver doesn't
514  * need it (e.g. in the scsi subsystem).
515  *
516  * Notes:
517  *   -  This interface is deprecated - users should use the SG_IO
518  *      interface instead, as this is a more flexible approach to
519  *      performing SCSI commands on a device.
520  *   -  The SCSI command length is determined by examining the 1st byte
521  *      of the given command. There is no way to override this.
522  *   -  Data transfers are limited to PAGE_SIZE
523  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
524  *      accommodate the sense buffer when an error occurs.
525  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
526  *      old code will not be surprised.
527  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
528  *      a negative return and the Unix error code in 'errno'.
529  *      If the SCSI command succeeds then 0 is returned.
530  *      Positive numbers returned are the compacted SCSI error codes (4
531  *      bytes in one int) where the lowest byte is the SCSI status.
532  */
533 static int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk,
534 		fmode_t mode, struct scsi_ioctl_command __user *sic)
535 {
536 	enum { OMAX_SB_LEN = 16 };	/* For backward compatibility */
537 	struct request *rq;
538 	struct scsi_request *req;
539 	int err;
540 	unsigned int in_len, out_len, bytes, opcode, cmdlen;
541 	char *buffer = NULL;
542 
543 	if (!sic)
544 		return -EINVAL;
545 
546 	/*
547 	 * get in an out lengths, verify they don't exceed a page worth of data
548 	 */
549 	if (get_user(in_len, &sic->inlen))
550 		return -EFAULT;
551 	if (get_user(out_len, &sic->outlen))
552 		return -EFAULT;
553 	if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
554 		return -EINVAL;
555 	if (get_user(opcode, sic->data))
556 		return -EFAULT;
557 
558 	bytes = max(in_len, out_len);
559 	if (bytes) {
560 		buffer = kzalloc(bytes, GFP_NOIO | GFP_USER | __GFP_NOWARN);
561 		if (!buffer)
562 			return -ENOMEM;
563 
564 	}
565 
566 	rq = scsi_alloc_request(q, in_len ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
567 	if (IS_ERR(rq)) {
568 		err = PTR_ERR(rq);
569 		goto error_free_buffer;
570 	}
571 	req = scsi_req(rq);
572 
573 	cmdlen = COMMAND_SIZE(opcode);
574 
575 	/*
576 	 * get command and data to send to device, if any
577 	 */
578 	err = -EFAULT;
579 	req->cmd_len = cmdlen;
580 	if (copy_from_user(req->cmd, sic->data, cmdlen))
581 		goto error;
582 
583 	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
584 		goto error;
585 
586 	err = -EPERM;
587 	if (!scsi_cmd_allowed(req->cmd, mode))
588 		goto error;
589 
590 	/* default.  possible overridden later */
591 	req->retries = 5;
592 
593 	switch (opcode) {
594 	case SEND_DIAGNOSTIC:
595 	case FORMAT_UNIT:
596 		rq->timeout = FORMAT_UNIT_TIMEOUT;
597 		req->retries = 1;
598 		break;
599 	case START_STOP:
600 		rq->timeout = START_STOP_TIMEOUT;
601 		break;
602 	case MOVE_MEDIUM:
603 		rq->timeout = MOVE_MEDIUM_TIMEOUT;
604 		break;
605 	case READ_ELEMENT_STATUS:
606 		rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
607 		break;
608 	case READ_DEFECT_DATA:
609 		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
610 		req->retries = 1;
611 		break;
612 	default:
613 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
614 		break;
615 	}
616 
617 	if (bytes) {
618 		err = blk_rq_map_kern(q, rq, buffer, bytes, GFP_NOIO);
619 		if (err)
620 			goto error;
621 	}
622 
623 	blk_execute_rq(disk, rq, 0);
624 
625 	err = req->result & 0xff;	/* only 8 bit SCSI status */
626 	if (err) {
627 		if (req->sense_len && req->sense) {
628 			bytes = (OMAX_SB_LEN > req->sense_len) ?
629 				req->sense_len : OMAX_SB_LEN;
630 			if (copy_to_user(sic->data, req->sense, bytes))
631 				err = -EFAULT;
632 		}
633 	} else {
634 		if (copy_to_user(sic->data, buffer, out_len))
635 			err = -EFAULT;
636 	}
637 
638 error:
639 	blk_mq_free_request(rq);
640 
641 error_free_buffer:
642 	kfree(buffer);
643 
644 	return err;
645 }
646 
647 int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp)
648 {
649 #ifdef CONFIG_COMPAT
650 	if (in_compat_syscall()) {
651 		struct compat_sg_io_hdr hdr32 =  {
652 			.interface_id	 = hdr->interface_id,
653 			.dxfer_direction = hdr->dxfer_direction,
654 			.cmd_len	 = hdr->cmd_len,
655 			.mx_sb_len	 = hdr->mx_sb_len,
656 			.iovec_count	 = hdr->iovec_count,
657 			.dxfer_len	 = hdr->dxfer_len,
658 			.dxferp		 = (uintptr_t)hdr->dxferp,
659 			.cmdp		 = (uintptr_t)hdr->cmdp,
660 			.sbp		 = (uintptr_t)hdr->sbp,
661 			.timeout	 = hdr->timeout,
662 			.flags		 = hdr->flags,
663 			.pack_id	 = hdr->pack_id,
664 			.usr_ptr	 = (uintptr_t)hdr->usr_ptr,
665 			.status		 = hdr->status,
666 			.masked_status	 = hdr->masked_status,
667 			.msg_status	 = hdr->msg_status,
668 			.sb_len_wr	 = hdr->sb_len_wr,
669 			.host_status	 = hdr->host_status,
670 			.driver_status	 = hdr->driver_status,
671 			.resid		 = hdr->resid,
672 			.duration	 = hdr->duration,
673 			.info		 = hdr->info,
674 		};
675 
676 		if (copy_to_user(argp, &hdr32, sizeof(hdr32)))
677 			return -EFAULT;
678 
679 		return 0;
680 	}
681 #endif
682 
683 	if (copy_to_user(argp, hdr, sizeof(*hdr)))
684 		return -EFAULT;
685 
686 	return 0;
687 }
688 EXPORT_SYMBOL(put_sg_io_hdr);
689 
690 int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp)
691 {
692 #ifdef CONFIG_COMPAT
693 	struct compat_sg_io_hdr hdr32;
694 
695 	if (in_compat_syscall()) {
696 		if (copy_from_user(&hdr32, argp, sizeof(hdr32)))
697 			return -EFAULT;
698 
699 		*hdr = (struct sg_io_hdr) {
700 			.interface_id	 = hdr32.interface_id,
701 			.dxfer_direction = hdr32.dxfer_direction,
702 			.cmd_len	 = hdr32.cmd_len,
703 			.mx_sb_len	 = hdr32.mx_sb_len,
704 			.iovec_count	 = hdr32.iovec_count,
705 			.dxfer_len	 = hdr32.dxfer_len,
706 			.dxferp		 = compat_ptr(hdr32.dxferp),
707 			.cmdp		 = compat_ptr(hdr32.cmdp),
708 			.sbp		 = compat_ptr(hdr32.sbp),
709 			.timeout	 = hdr32.timeout,
710 			.flags		 = hdr32.flags,
711 			.pack_id	 = hdr32.pack_id,
712 			.usr_ptr	 = compat_ptr(hdr32.usr_ptr),
713 			.status		 = hdr32.status,
714 			.masked_status	 = hdr32.masked_status,
715 			.msg_status	 = hdr32.msg_status,
716 			.sb_len_wr	 = hdr32.sb_len_wr,
717 			.host_status	 = hdr32.host_status,
718 			.driver_status	 = hdr32.driver_status,
719 			.resid		 = hdr32.resid,
720 			.duration	 = hdr32.duration,
721 			.info		 = hdr32.info,
722 		};
723 
724 		return 0;
725 	}
726 #endif
727 
728 	if (copy_from_user(hdr, argp, sizeof(*hdr)))
729 		return -EFAULT;
730 
731 	return 0;
732 }
733 EXPORT_SYMBOL(get_sg_io_hdr);
734 
735 #ifdef CONFIG_COMPAT
736 struct compat_cdrom_generic_command {
737 	unsigned char	cmd[CDROM_PACKET_SIZE];
738 	compat_caddr_t	buffer;
739 	compat_uint_t	buflen;
740 	compat_int_t	stat;
741 	compat_caddr_t	sense;
742 	unsigned char	data_direction;
743 	unsigned char	pad[3];
744 	compat_int_t	quiet;
745 	compat_int_t	timeout;
746 	compat_caddr_t	unused;
747 };
748 #endif
749 
750 static int scsi_get_cdrom_generic_arg(struct cdrom_generic_command *cgc,
751 				      const void __user *arg)
752 {
753 #ifdef CONFIG_COMPAT
754 	if (in_compat_syscall()) {
755 		struct compat_cdrom_generic_command cgc32;
756 
757 		if (copy_from_user(&cgc32, arg, sizeof(cgc32)))
758 			return -EFAULT;
759 
760 		*cgc = (struct cdrom_generic_command) {
761 			.buffer		= compat_ptr(cgc32.buffer),
762 			.buflen		= cgc32.buflen,
763 			.stat		= cgc32.stat,
764 			.sense		= compat_ptr(cgc32.sense),
765 			.data_direction	= cgc32.data_direction,
766 			.quiet		= cgc32.quiet,
767 			.timeout	= cgc32.timeout,
768 			.unused		= compat_ptr(cgc32.unused),
769 		};
770 		memcpy(&cgc->cmd, &cgc32.cmd, CDROM_PACKET_SIZE);
771 		return 0;
772 	}
773 #endif
774 	if (copy_from_user(cgc, arg, sizeof(*cgc)))
775 		return -EFAULT;
776 
777 	return 0;
778 }
779 
780 static int scsi_put_cdrom_generic_arg(const struct cdrom_generic_command *cgc,
781 				      void __user *arg)
782 {
783 #ifdef CONFIG_COMPAT
784 	if (in_compat_syscall()) {
785 		struct compat_cdrom_generic_command cgc32 = {
786 			.buffer		= (uintptr_t)(cgc->buffer),
787 			.buflen		= cgc->buflen,
788 			.stat		= cgc->stat,
789 			.sense		= (uintptr_t)(cgc->sense),
790 			.data_direction	= cgc->data_direction,
791 			.quiet		= cgc->quiet,
792 			.timeout	= cgc->timeout,
793 			.unused		= (uintptr_t)(cgc->unused),
794 		};
795 		memcpy(&cgc32.cmd, &cgc->cmd, CDROM_PACKET_SIZE);
796 
797 		if (copy_to_user(arg, &cgc32, sizeof(cgc32)))
798 			return -EFAULT;
799 
800 		return 0;
801 	}
802 #endif
803 	if (copy_to_user(arg, cgc, sizeof(*cgc)))
804 		return -EFAULT;
805 
806 	return 0;
807 }
808 
809 static int scsi_cdrom_send_packet(struct scsi_device *sdev, struct gendisk *disk,
810 		fmode_t mode, void __user *arg)
811 {
812 	struct cdrom_generic_command cgc;
813 	struct sg_io_hdr hdr;
814 	int err;
815 
816 	err = scsi_get_cdrom_generic_arg(&cgc, arg);
817 	if (err)
818 		return err;
819 
820 	cgc.timeout = clock_t_to_jiffies(cgc.timeout);
821 	memset(&hdr, 0, sizeof(hdr));
822 	hdr.interface_id = 'S';
823 	hdr.cmd_len = sizeof(cgc.cmd);
824 	hdr.dxfer_len = cgc.buflen;
825 	switch (cgc.data_direction) {
826 	case CGC_DATA_UNKNOWN:
827 		hdr.dxfer_direction = SG_DXFER_UNKNOWN;
828 		break;
829 	case CGC_DATA_WRITE:
830 		hdr.dxfer_direction = SG_DXFER_TO_DEV;
831 		break;
832 	case CGC_DATA_READ:
833 		hdr.dxfer_direction = SG_DXFER_FROM_DEV;
834 		break;
835 	case CGC_DATA_NONE:
836 		hdr.dxfer_direction = SG_DXFER_NONE;
837 		break;
838 	default:
839 		return -EINVAL;
840 	}
841 
842 	hdr.dxferp = cgc.buffer;
843 	hdr.sbp = cgc.sense;
844 	if (hdr.sbp)
845 		hdr.mx_sb_len = sizeof(struct request_sense);
846 	hdr.timeout = jiffies_to_msecs(cgc.timeout);
847 	hdr.cmdp = ((struct cdrom_generic_command __user *) arg)->cmd;
848 	hdr.cmd_len = sizeof(cgc.cmd);
849 
850 	err = sg_io(sdev, disk, &hdr, mode);
851 	if (err == -EFAULT)
852 		return -EFAULT;
853 
854 	if (hdr.status)
855 		return -EIO;
856 
857 	cgc.stat = err;
858 	cgc.buflen = hdr.resid;
859 	if (scsi_put_cdrom_generic_arg(&cgc, arg))
860 		return -EFAULT;
861 
862 	return err;
863 }
864 
865 static int scsi_ioctl_sg_io(struct scsi_device *sdev, struct gendisk *disk,
866 		fmode_t mode, void __user *argp)
867 {
868 	struct sg_io_hdr hdr;
869 	int error;
870 
871 	error = get_sg_io_hdr(&hdr, argp);
872 	if (error)
873 		return error;
874 	error = sg_io(sdev, disk, &hdr, mode);
875 	if (error == -EFAULT)
876 		return error;
877 	if (put_sg_io_hdr(&hdr, argp))
878 		return -EFAULT;
879 	return error;
880 }
881 
882 /**
883  * scsi_ioctl - Dispatch ioctl to scsi device
884  * @sdev: scsi device receiving ioctl
885  * @disk: disk receiving the ioctl
886  * @mode: mode the block/char device is opened with
887  * @cmd: which ioctl is it
888  * @arg: data associated with ioctl
889  *
890  * Description: The scsi_ioctl() function differs from most ioctls in that it
891  * does not take a major/minor number as the dev field.  Rather, it takes
892  * a pointer to a &struct scsi_device.
893  */
894 int scsi_ioctl(struct scsi_device *sdev, struct gendisk *disk, fmode_t mode,
895 		int cmd, void __user *arg)
896 {
897 	struct request_queue *q = sdev->request_queue;
898 	struct scsi_sense_hdr sense_hdr;
899 
900 	/* Check for deprecated ioctls ... all the ioctls which don't
901 	 * follow the new unique numbering scheme are deprecated */
902 	switch (cmd) {
903 	case SCSI_IOCTL_SEND_COMMAND:
904 	case SCSI_IOCTL_TEST_UNIT_READY:
905 	case SCSI_IOCTL_BENCHMARK_COMMAND:
906 	case SCSI_IOCTL_SYNC:
907 	case SCSI_IOCTL_START_UNIT:
908 	case SCSI_IOCTL_STOP_UNIT:
909 		printk(KERN_WARNING "program %s is using a deprecated SCSI "
910 		       "ioctl, please convert it to SG_IO\n", current->comm);
911 		break;
912 	default:
913 		break;
914 	}
915 
916 	switch (cmd) {
917 	case SG_GET_VERSION_NUM:
918 		return sg_get_version(arg);
919 	case SG_SET_TIMEOUT:
920 		return sg_set_timeout(sdev, arg);
921 	case SG_GET_TIMEOUT:
922 		return jiffies_to_clock_t(sdev->sg_timeout);
923 	case SG_GET_RESERVED_SIZE:
924 		return sg_get_reserved_size(sdev, arg);
925 	case SG_SET_RESERVED_SIZE:
926 		return sg_set_reserved_size(sdev, arg);
927 	case SG_EMULATED_HOST:
928 		return sg_emulated_host(q, arg);
929 	case SG_IO:
930 		return scsi_ioctl_sg_io(sdev, disk, mode, arg);
931 	case SCSI_IOCTL_SEND_COMMAND:
932 		return sg_scsi_ioctl(q, disk, mode, arg);
933 	case CDROM_SEND_PACKET:
934 		return scsi_cdrom_send_packet(sdev, disk, mode, arg);
935 	case CDROMCLOSETRAY:
936 		return scsi_send_start_stop(sdev, 3);
937 	case CDROMEJECT:
938 		return scsi_send_start_stop(sdev, 2);
939 	case SCSI_IOCTL_GET_IDLUN:
940 		return scsi_get_idlun(sdev, arg);
941 	case SCSI_IOCTL_GET_BUS_NUMBER:
942 		return put_user(sdev->host->host_no, (int __user *)arg);
943 	case SCSI_IOCTL_PROBE_HOST:
944 		return ioctl_probe(sdev->host, arg);
945 	case SCSI_IOCTL_DOORLOCK:
946 		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
947 	case SCSI_IOCTL_DOORUNLOCK:
948 		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
949 	case SCSI_IOCTL_TEST_UNIT_READY:
950 		return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
951 					    NORMAL_RETRIES, &sense_hdr);
952 	case SCSI_IOCTL_START_UNIT:
953 		return scsi_send_start_stop(sdev, 1);
954 	case SCSI_IOCTL_STOP_UNIT:
955 		return scsi_send_start_stop(sdev, 0);
956         case SCSI_IOCTL_GET_PCI:
957                 return scsi_ioctl_get_pci(sdev, arg);
958 	case SG_SCSI_RESET:
959 		return scsi_ioctl_reset(sdev, arg);
960 	}
961 
962 #ifdef CONFIG_COMPAT
963 	if (in_compat_syscall()) {
964 		if (!sdev->host->hostt->compat_ioctl)
965 			return -EINVAL;
966 		return sdev->host->hostt->compat_ioctl(sdev, cmd, arg);
967 	}
968 #endif
969 	if (!sdev->host->hostt->ioctl)
970 		return -EINVAL;
971 	return sdev->host->hostt->ioctl(sdev, cmd, arg);
972 }
973 EXPORT_SYMBOL(scsi_ioctl);
974 
975 /*
976  * We can process a reset even when a device isn't fully operable.
977  */
978 int scsi_ioctl_block_when_processing_errors(struct scsi_device *sdev, int cmd,
979 		bool ndelay)
980 {
981 	if (cmd == SG_SCSI_RESET && ndelay) {
982 		if (scsi_host_in_recovery(sdev->host))
983 			return -EAGAIN;
984 	} else {
985 		if (!scsi_block_when_processing_errors(sdev))
986 			return -ENODEV;
987 	}
988 
989 	return 0;
990 }
991 EXPORT_SYMBOL_GPL(scsi_ioctl_block_when_processing_errors);
992