summaryrefslogtreecommitdiff
path: root/drivers/scsi/scsi_ioctl.c
blob: 6f6c5973c3ea95d91af230689084b68e6a8d3f32 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Changes:
 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000
 * - get rid of some verify_areas and use __copy*user and __get/put_user
 *   for the ones that remain
 */
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/cdrom.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/sg.h>
#include <scsi/scsi_dbg.h>

#include "scsi_logging.h"

#define NORMAL_RETRIES			5
#define IOCTL_NORMAL_TIMEOUT			(10 * HZ)

#define MAX_BUF PAGE_SIZE

/**
 * ioctl_probe  --  return host identification
 * @host:	host to identify
 * @buffer:	userspace buffer for identification
 *
 * Return an identifying string at @buffer, if @buffer is non-NULL, filling
 * to the length stored at * (int *) @buffer.
 */
static int ioctl_probe(struct Scsi_Host *host, void __user *buffer)
{
	unsigned int len, slen;
	const char *string;

	if (buffer) {
		if (get_user(len, (unsigned int __user *) buffer))
			return -EFAULT;

		if (host->hostt->info)
			string = host->hostt->info(host);
		else
			string = host->hostt->name;
		if (string) {
			slen = strlen(string);
			if (len > slen)
				len = slen + 1;
			if (copy_to_user(buffer, string, len))
				return -EFAULT;
		}
	}
	return 1;
}

static int ioctl_internal_command(struct scsi_device *sdev, char *cmd,
				  int timeout, int retries)
{
	int result;
	struct scsi_sense_hdr sshdr;
	const struct scsi_exec_args exec_args = {
		.sshdr = &sshdr,
	};

	SCSI_LOG_IOCTL(1, sdev_printk(KERN_INFO, sdev,
				      "Trying ioctl with scsi command %d\n", *cmd));

	result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, NULL, 0, timeout,
				  retries, &exec_args);

	SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
				      "Ioctl returned  0x%x\n", result));

	if (result < 0)
		goto out;
	if (scsi_sense_valid(&sshdr)) {
		switch (sshdr.sense_key) {
		case ILLEGAL_REQUEST:
			if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
				sdev->lockable = 0;
			else
				sdev_printk(KERN_INFO, sdev,
					    "ioctl_internal_command: "
					    "ILLEGAL REQUEST "
					    "asc=0x%x ascq=0x%x\n",
					    sshdr.asc, sshdr.ascq);
			break;
		case NOT_READY:	/* This happens if there is no disc in drive */
			if (sdev->removable)
				break;
			fallthrough;
		case UNIT_ATTENTION:
			if (sdev->removable) {
				sdev->changed = 1;
				result = 0;	/* This is no longer considered an error */
				break;
			}
			fallthrough;	/* for non-removable media */
		default:
			sdev_printk(KERN_INFO, sdev,
				    "ioctl_internal_command return code = %x\n",
				    result);
			scsi_print_sense_hdr(sdev, NULL, &sshdr);
			break;
		}
	}
out:
	SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
				      "IOCTL Releasing command\n"));
	return result;
}

int scsi_set_medium_removal(struct scsi_device *sdev, char state)
{
	char scsi_cmd[MAX_COMMAND_SIZE];
	int ret;

	if (!sdev->removable || !sdev->lockable)
	       return 0;

	scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
	scsi_cmd[1] = 0;
	scsi_cmd[2] = 0;
	scsi_cmd[3] = 0;
	scsi_cmd[4] = state;
	scsi_cmd[5] = 0;

	ret = ioctl_internal_command(sdev, scsi_cmd,
			IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
	if (ret == 0)
		sdev->locked = (state == SCSI_REMOVAL_PREVENT);
	return ret;
}
EXPORT_SYMBOL(scsi_set_medium_removal);

/*
 * The scsi_ioctl_get_pci() function places into arg the value
 * pci_dev::slot_name (8 characters) for the PCI device (if any).
 * Returns: 0 on success
 *          -ENXIO if there isn't a PCI device pointer
 *                 (could be because the SCSI driver hasn't been
 *                  updated yet, or because it isn't a SCSI
 *                  device)
 *          any copy_to_user() error on failure there
 */
static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg)
{
	struct device *dev = scsi_get_device(sdev->host);
	const char *name;

        if (!dev)
		return -ENXIO;

	name = dev_name(dev);

	/* compatibility with old ioctl which only returned
	 * 20 characters */
        return copy_to_user(arg, name, min(strlen(name), (size_t)20))
		? -EFAULT: 0;
}

static int sg_get_version(int __user *p)
{
	static const int sg_version_num = 30527;
	return put_user(sg_version_num, p);
}

static int sg_set_timeout(struct scsi_device *sdev, int __user *p)
{
	int timeout, err = get_user(timeout, p);

	if (!err)
		sdev->sg_timeout = clock_t_to_jiffies(timeout);

	return err;
}

static int sg_get_reserved_size(struct scsi_device *sdev, int __user *p)
{
	int val = min(sdev->sg_reserved_size,
		      queue_max_bytes(sdev->request_queue));

	return put_user(val, p);
}

static int sg_set_reserved_size(struct scsi_device *sdev, int __user *p)
{
	int size, err = get_user(size, p);

	if (err)
		return err;

	if (size < 0)
		return -EINVAL;

	sdev->sg_reserved_size = min_t(unsigned int, size,
				       queue_max_bytes(sdev->request_queue));
	return 0;
}

/*
 * will always return that we are ATAPI even for a real SCSI drive, I'm not
 * so sure this is worth doing anything about (why would you care??)
 */
static int sg_emulated_host(struct request_queue *q, int __user *p)
{
	return put_user(1, p);
}

static int scsi_get_idlun(struct scsi_device *sdev, void __user *argp)
{
	struct scsi_idlun v = {
		.dev_id = (sdev->id & 0xff) +
			((sdev->lun & 0xff) << 8) +
			((sdev->channel & 0xff) << 16) +
			((sdev->host->host_no & 0xff) << 24),
		.host_unique_id = sdev->host->unique_id
	};
	if (copy_to_user(argp, &v, sizeof(struct scsi_idlun)))
		return -EFAULT;
	return 0;
}

static int scsi_send_start_stop(struct scsi_device *sdev, int data)
{
	u8 cdb[MAX_COMMAND_SIZE] = { };

	cdb[0] = START_STOP;
	cdb[4] = data;
	return ioctl_internal_command(sdev, cdb, START_STOP_TIMEOUT,
				      NORMAL_RETRIES);
}

/*
 * Check if the given command is allowed.
 *
 * Only a subset of commands are allowed for unprivileged users. Commands used
 * to format the media, update the firmware, etc. are not permitted.
 */
bool scsi_cmd_allowed(unsigned char *cmd, bool open_for_write)
{
	/* root can do any command. */
	if (capable(CAP_SYS_RAWIO))
		return true;

	/* Anybody who can open the device can do a read-safe command */
	switch (cmd[0]) {
	/* Basic read-only commands */
	case TEST_UNIT_READY:
	case REQUEST_SENSE:
	case READ_6:
	case READ_10:
	case READ_12:
	case READ_16:
	case READ_BUFFER:
	case READ_DEFECT_DATA:
	case READ_CAPACITY: /* also GPCMD_READ_CDVD_CAPACITY */
	case READ_LONG:
	case INQUIRY:
	case MODE_SENSE:
	case MODE_SENSE_10:
	case LOG_SENSE:
	case START_STOP:
	case GPCMD_VERIFY_10:
	case VERIFY_16:
	case REPORT_LUNS:
	case SERVICE_ACTION_IN_16:
	case RECEIVE_DIAGNOSTIC:
	case MAINTENANCE_IN: /* also GPCMD_SEND_KEY, which is a write command */
	case GPCMD_READ_BUFFER_CAPACITY:
	/* Audio CD commands */
	case GPCMD_PLAY_CD:
	case GPCMD_PLAY_AUDIO_10:
	case GPCMD_PLAY_AUDIO_MSF:
	case GPCMD_PLAY_AUDIO_TI:
	case GPCMD_PAUSE_RESUME:
	/* CD/DVD data reading */
	case GPCMD_READ_CD:
	case GPCMD_READ_CD_MSF:
	case GPCMD_READ_DISC_INFO:
	case GPCMD_READ_DVD_STRUCTURE:
	case GPCMD_READ_HEADER:
	case GPCMD_READ_TRACK_RZONE_INFO:
	case GPCMD_READ_SUBCHANNEL:
	case GPCMD_READ_TOC_PMA_ATIP:
	case GPCMD_REPORT_KEY:
	case GPCMD_SCAN:
	case GPCMD_GET_CONFIGURATION:
	case GPCMD_READ_FORMAT_CAPACITIES:
	case GPCMD_GET_EVENT_STATUS_NOTIFICATION:
	case GPCMD_GET_PERFORMANCE:
	case GPCMD_SEEK:
	case GPCMD_STOP_PLAY_SCAN:
	/* ZBC */
	case ZBC_IN:
		return true;
	/* Basic writing commands */
	case WRITE_6:
	case WRITE_10:
	case WRITE_VERIFY:
	case WRITE_12:
	case WRITE_VERIFY_12:
	case WRITE_16:
	case WRITE_LONG:
	case WRITE_LONG_2:
	case WRITE_SAME:
	case WRITE_SAME_16:
	case WRITE_SAME_32:
	case ERASE:
	case GPCMD_MODE_SELECT_10:
	case MODE_SELECT:
	case LOG_SELECT:
	case GPCMD_BLANK:
	case GPCMD_CLOSE_TRACK:
	case GPCMD_FLUSH_CACHE:
	case GPCMD_FORMAT_UNIT:
	case GPCMD_REPAIR_RZONE_TRACK:
	case GPCMD_RESERVE_RZONE_TRACK:
	case GPCMD_SEND_DVD_STRUCTURE:
	case GPCMD_SEND_EVENT:
	case GPCMD_SEND_OPC:
	case GPCMD_SEND_CUE_SHEET:
	case GPCMD_SET_SPEED:
	case GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
	case GPCMD_LOAD_UNLOAD:
	case GPCMD_SET_STREAMING:
	case GPCMD_SET_READ_AHEAD:
	/* ZBC */
	case ZBC_OUT:
		return open_for_write;
	default:
		return false;
	}
}
EXPORT_SYMBOL(scsi_cmd_allowed);

static int scsi_fill_sghdr_rq(struct scsi_device *sdev, struct request *rq,
		struct sg_io_hdr *hdr, bool open_for_write)
{
	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);

	if (hdr->cmd_len < 6)
		return -EMSGSIZE;
	if (copy_from_user(scmd->cmnd, hdr->cmdp, hdr->cmd_len))
		return -EFAULT;
	if (!scsi_cmd_allowed(scmd->cmnd, open_for_write))
		return -EPERM;
	scmd->cmd_len = hdr->cmd_len;

	rq->timeout = msecs_to_jiffies(hdr->timeout);
	if (!rq->timeout)
		rq->timeout = sdev->sg_timeout;
	if (!rq->timeout)
		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
	if (rq->timeout < BLK_MIN_SG_TIMEOUT)
		rq->timeout = BLK_MIN_SG_TIMEOUT;

	return 0;
}

static int scsi_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
		struct bio *bio)
{
	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
	int r, ret = 0;

	/*
	 * fill in all the output members
	 */
	hdr->status = scmd->result & 0xff;
	hdr->masked_status = sg_status_byte(scmd->result);
	hdr->msg_status = COMMAND_COMPLETE;
	hdr->host_status = host_byte(scmd->result);
	hdr->driver_status = 0;
	if (scsi_status_is_check_condition(hdr->status))
		hdr->driver_status = DRIVER_SENSE;
	hdr->info = 0;
	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
		hdr->info |= SG_INFO_CHECK;
	hdr->resid = scmd->resid_len;
	hdr->sb_len_wr = 0;

	if (scmd->sense_len && hdr->sbp) {
		int len = min((unsigned int) hdr->mx_sb_len, scmd->sense_len);

		if (!copy_to_user(hdr->sbp, scmd->sense_buffer, len))
			hdr->sb_len_wr = len;
		else
			ret = -EFAULT;
	}

	r = blk_rq_unmap_user(bio);
	if (!ret)
		ret = r;

	return ret;
}

static int sg_io(struct scsi_device *sdev, struct sg_io_hdr *hdr,
		bool open_for_write)
{
	unsigned long start_time;
	ssize_t ret = 0;
	int writing = 0;
	int at_head = 0;
	struct request *rq;
	struct scsi_cmnd *scmd;
	struct bio *bio;

	if (hdr->interface_id != 'S')
		return -EINVAL;

	if (hdr->dxfer_len > (queue_max_hw_sectors(sdev->request_queue) << 9))
		return -EIO;

	if (hdr->dxfer_len)
		switch (hdr->dxfer_direction) {
		default:
			return -EINVAL;
		case SG_DXFER_TO_DEV:
			writing = 1;
			break;
		case SG_DXFER_TO_FROM_DEV:
		case SG_DXFER_FROM_DEV:
			break;
		}
	if (hdr->flags & SG_FLAG_Q_AT_HEAD)
		at_head = 1;

	rq = scsi_alloc_request(sdev->request_queue, writing ?
			     REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
	if (IS_ERR(rq))
		return PTR_ERR(rq);
	scmd = blk_mq_rq_to_pdu(rq);

	if (hdr->cmd_len > sizeof(scmd->cmnd)) {
		ret = -EINVAL;
		goto out_put_request;
	}

	ret = scsi_fill_sghdr_rq(sdev, rq, hdr, open_for_write);
	if (ret < 0)
		goto out_put_request;

	ret = blk_rq_map_user_io(rq, NULL, hdr->dxferp, hdr->dxfer_len,
			GFP_KERNEL, hdr->iovec_count && hdr->dxfer_len,
			hdr->iovec_count, 0, rq_data_dir(rq));
	if (ret)
		goto out_put_request;

	bio = rq->bio;
	scmd->allowed = 0;

	start_time = jiffies;

	blk_execute_rq(rq, at_head);

	hdr->duration = jiffies_to_msecs(jiffies - start_time);

	ret = scsi_complete_sghdr_rq(rq, hdr, bio);

out_put_request:
	blk_mq_free_request(rq);
	return ret;
}

/**
 * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
 * @q:		request queue to send scsi commands down
 * @open_for_write: is the file / block device opened for writing?
 * @sic:	userspace structure describing the command to perform
 *
 * Send down the scsi command described by @sic to the device below
 * the request queue @q.
 *
 * Notes:
 *   -  This interface is deprecated - users should use the SG_IO
 *      interface instead, as this is a more flexible approach to
 *      performing SCSI commands on a device.
 *   -  The SCSI command length is determined by examining the 1st byte
 *      of the given command. There is no way to override this.
 *   -  Data transfers are limited to PAGE_SIZE
 *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
 *      accommodate the sense buffer when an error occurs.
 *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
 *      old code will not be surprised.
 *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
 *      a negative return and the Unix error code in 'errno'.
 *      If the SCSI command succeeds then 0 is returned.
 *      Positive numbers returned are the compacted SCSI error codes (4
 *      bytes in one int) where the lowest byte is the SCSI status.
 */
static int sg_scsi_ioctl(struct request_queue *q, bool open_for_write,
		struct scsi_ioctl_command __user *sic)
{
	struct request *rq;
	int err;
	unsigned int in_len, out_len, bytes, opcode, cmdlen;
	struct scsi_cmnd *scmd;
	char *buffer = NULL;

	if (!sic)
		return -EINVAL;

	/*
	 * get in an out lengths, verify they don't exceed a page worth of data
	 */
	if (get_user(in_len, &sic->inlen))
		return -EFAULT;
	if (get_user(out_len, &sic->outlen))
		return -EFAULT;
	if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
		return -EINVAL;
	if (get_user(opcode, &sic->data[0]))
		return -EFAULT;

	bytes = max(in_len, out_len);
	if (bytes) {
		buffer = kzalloc(bytes, GFP_NOIO | GFP_USER | __GFP_NOWARN);
		if (!buffer)
			return -ENOMEM;

	}

	rq = scsi_alloc_request(q, in_len ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
	if (IS_ERR(rq)) {
		err = PTR_ERR(rq);
		goto error_free_buffer;
	}
	scmd = blk_mq_rq_to_pdu(rq);

	cmdlen = COMMAND_SIZE(opcode);

	/*
	 * get command and data to send to device, if any
	 */
	err = -EFAULT;
	scmd->cmd_len = cmdlen;
	if (copy_from_user(scmd->cmnd, sic->data, cmdlen))
		goto error;

	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
		goto error;

	err = -EPERM;
	if (!scsi_cmd_allowed(scmd->cmnd, open_for_write))
		goto error;

	/* default.  possible overridden later */
	scmd->allowed = 5;

	switch (opcode) {
	case SEND_DIAGNOSTIC:
	case FORMAT_UNIT:
		rq->timeout = FORMAT_UNIT_TIMEOUT;
		scmd->allowed = 1;
		break;
	case START_STOP:
		rq->timeout = START_STOP_TIMEOUT;
		break;
	case MOVE_MEDIUM:
		rq->timeout = MOVE_MEDIUM_TIMEOUT;
		break;
	case READ_ELEMENT_STATUS:
		rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
		break;
	case READ_DEFECT_DATA:
		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
		scmd->allowed = 1;
		break;
	default:
		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
		break;
	}

	if (bytes) {
		err = blk_rq_map_kern(q, rq, buffer, bytes, GFP_NOIO);
		if (err)
			goto error;
	}

	blk_execute_rq(rq, false);

	err = scmd->result & 0xff;	/* only 8 bit SCSI status */
	if (err) {
		if (scmd->sense_len && scmd->sense_buffer) {
			/* limit sense len for backward compatibility */
			if (copy_to_user(sic->data, scmd->sense_buffer,
					 min(scmd->sense_len, 16U)))
				err = -EFAULT;
		}
	} else {
		if (copy_to_user(sic->data, buffer, out_len))
			err = -EFAULT;
	}

error:
	blk_mq_free_request(rq);

error_free_buffer:
	kfree(buffer);

	return err;
}

int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp)
{
#ifdef CONFIG_COMPAT
	if (in_compat_syscall()) {
		struct compat_sg_io_hdr hdr32 =  {
			.interface_id	 = hdr->interface_id,
			.dxfer_direction = hdr->dxfer_direction,
			.cmd_len	 = hdr->cmd_len,
			.mx_sb_len	 = hdr->mx_sb_len,
			.iovec_count	 = hdr->iovec_count,
			.dxfer_len	 = hdr->dxfer_len,
			.dxferp		 = (uintptr_t)hdr->dxferp,
			.cmdp		 = (uintptr_t)hdr->cmdp,
			.sbp		 = (uintptr_t)hdr->sbp,
			.timeout	 = hdr->timeout,
			.flags		 = hdr->flags,
			.pack_id	 = hdr->pack_id,
			.usr_ptr	 = (uintptr_t)hdr->usr_ptr,
			.status		 = hdr->status,
			.masked_status	 = hdr->masked_status,
			.msg_status	 = hdr->msg_status,
			.sb_len_wr	 = hdr->sb_len_wr,
			.host_status	 = hdr->host_status,
			.driver_status	 = hdr->driver_status,
			.resid		 = hdr->resid,
			.duration	 = hdr->duration,
			.info		 = hdr->info,
		};

		if (copy_to_user(argp, &hdr32, sizeof(hdr32)))
			return -EFAULT;

		return 0;
	}
#endif

	if (copy_to_user(argp, hdr, sizeof(*hdr)))
		return -EFAULT;

	return 0;
}
EXPORT_SYMBOL(put_sg_io_hdr);

int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp)
{
#ifdef CONFIG_COMPAT
	struct compat_sg_io_hdr hdr32;

	if (in_compat_syscall()) {
		if (copy_from_user(&hdr32, argp, sizeof(hdr32)))
			return -EFAULT;

		*hdr = (struct sg_io_hdr) {
			.interface_id	 = hdr32.interface_id,
			.dxfer_direction = hdr32.dxfer_direction,
			.cmd_len	 = hdr32.cmd_len,
			.mx_sb_len	 = hdr32.mx_sb_len,
			.iovec_count	 = hdr32.iovec_count,
			.dxfer_len	 = hdr32.dxfer_len,
			.dxferp		 = compat_ptr(hdr32.dxferp),
			.cmdp		 = compat_ptr(hdr32.cmdp),
			.sbp		 = compat_ptr(hdr32.sbp),
			.timeout	 = hdr32.timeout,
			.flags		 = hdr32.flags,
			.pack_id	 = hdr32.pack_id,
			.usr_ptr	 = compat_ptr(hdr32.usr_ptr),
			.status		 = hdr32.status,
			.masked_status	 = hdr32.masked_status,
			.msg_status	 = hdr32.msg_status,
			.sb_len_wr	 = hdr32.sb_len_wr,
			.host_status	 = hdr32.host_status,
			.driver_status	 = hdr32.driver_status,
			.resid		 = hdr32.resid,
			.duration	 = hdr32.duration,
			.info		 = hdr32.info,
		};

		return 0;
	}
#endif

	if (copy_from_user(hdr, argp, sizeof(*hdr)))
		return -EFAULT;

	return 0;
}
EXPORT_SYMBOL(get_sg_io_hdr);

#ifdef CONFIG_COMPAT
struct compat_cdrom_generic_command {
	unsigned char	cmd[CDROM_PACKET_SIZE];
	compat_caddr_t	buffer;
	compat_uint_t	buflen;
	compat_int_t	stat;
	compat_caddr_t	sense;
	unsigned char	data_direction;
	unsigned char	pad[3];
	compat_int_t	quiet;
	compat_int_t	timeout;
	compat_caddr_t	unused;
};
#endif

static int scsi_get_cdrom_generic_arg(struct cdrom_generic_command *cgc,
				      const void __user *arg)
{
#ifdef CONFIG_COMPAT
	if (in_compat_syscall()) {
		struct compat_cdrom_generic_command cgc32;

		if (copy_from_user(&cgc32, arg, sizeof(cgc32)))
			return -EFAULT;

		*cgc = (struct cdrom_generic_command) {
			.buffer		= compat_ptr(cgc32.buffer),
			.buflen		= cgc32.buflen,
			.stat		= cgc32.stat,
			.sense		= compat_ptr(cgc32.sense),
			.data_direction	= cgc32.data_direction,
			.quiet		= cgc32.quiet,
			.timeout	= cgc32.timeout,
			.unused		= compat_ptr(cgc32.unused),
		};
		memcpy(&cgc->cmd, &cgc32.cmd, CDROM_PACKET_SIZE);
		return 0;
	}
#endif
	if (copy_from_user(cgc, arg, sizeof(*cgc)))
		return -EFAULT;

	return 0;
}

static int scsi_put_cdrom_generic_arg(const struct cdrom_generic_command *cgc,
				      void __user *arg)
{
#ifdef CONFIG_COMPAT
	if (in_compat_syscall()) {
		struct compat_cdrom_generic_command cgc32 = {
			.buffer		= (uintptr_t)(cgc->buffer),
			.buflen		= cgc->buflen,
			.stat		= cgc->stat,
			.sense		= (uintptr_t)(cgc->sense),
			.data_direction	= cgc->data_direction,
			.quiet		= cgc->quiet,
			.timeout	= cgc->timeout,
			.unused		= (uintptr_t)(cgc->unused),
		};
		memcpy(&cgc32.cmd, &cgc->cmd, CDROM_PACKET_SIZE);

		if (copy_to_user(arg, &cgc32, sizeof(cgc32)))
			return -EFAULT;

		return 0;
	}
#endif
	if (copy_to_user(arg, cgc, sizeof(*cgc)))
		return -EFAULT;

	return 0;
}

static int scsi_cdrom_send_packet(struct scsi_device *sdev, bool open_for_write,
		void __user *arg)
{
	struct cdrom_generic_command cgc;
	struct sg_io_hdr hdr;
	int err;

	err = scsi_get_cdrom_generic_arg(&cgc, arg);
	if (err)
		return err;

	cgc.timeout = clock_t_to_jiffies(cgc.timeout);
	memset(&hdr, 0, sizeof(hdr));
	hdr.interface_id = 'S';
	hdr.cmd_len = sizeof(cgc.cmd);
	hdr.dxfer_len = cgc.buflen;
	switch (cgc.data_direction) {
	case CGC_DATA_UNKNOWN:
		hdr.dxfer_direction = SG_DXFER_UNKNOWN;
		break;
	case CGC_DATA_WRITE:
		hdr.dxfer_direction = SG_DXFER_TO_DEV;
		break;
	case CGC_DATA_READ:
		hdr.dxfer_direction = SG_DXFER_FROM_DEV;
		break;
	case CGC_DATA_NONE:
		hdr.dxfer_direction = SG_DXFER_NONE;
		break;
	default:
		return -EINVAL;
	}

	hdr.dxferp = cgc.buffer;
	hdr.sbp = cgc.sense;
	if (hdr.sbp)
		hdr.mx_sb_len = sizeof(struct request_sense);
	hdr.timeout = jiffies_to_msecs(cgc.timeout);
	hdr.cmdp = ((struct cdrom_generic_command __user *) arg)->cmd;
	hdr.cmd_len = sizeof(cgc.cmd);

	err = sg_io(sdev, &hdr, open_for_write);
	if (err == -EFAULT)
		return -EFAULT;

	if (hdr.status)
		return -EIO;

	cgc.stat = err;
	cgc.buflen = hdr.resid;
	if (scsi_put_cdrom_generic_arg(&cgc, arg))
		return -EFAULT;

	return err;
}

static int scsi_ioctl_sg_io(struct scsi_device *sdev, bool open_for_write,
		void __user *argp)
{
	struct sg_io_hdr hdr;
	int error;

	error = get_sg_io_hdr(&hdr, argp);
	if (error)
		return error;
	error = sg_io(sdev, &hdr, open_for_write);
	if (error == -EFAULT)
		return error;
	if (put_sg_io_hdr(&hdr, argp))
		return -EFAULT;
	return error;
}

/**
 * scsi_ioctl - Dispatch ioctl to scsi device
 * @sdev: scsi device receiving ioctl
 * @open_for_write: is the file / block device opened for writing?
 * @cmd: which ioctl is it
 * @arg: data associated with ioctl
 *
 * Description: The scsi_ioctl() function differs from most ioctls in that it
 * does not take a major/minor number as the dev field.  Rather, it takes
 * a pointer to a &struct scsi_device.
 */
int scsi_ioctl(struct scsi_device *sdev, bool open_for_write, int cmd,
		void __user *arg)
{
	struct request_queue *q = sdev->request_queue;
	struct scsi_sense_hdr sense_hdr;

	/* Check for deprecated ioctls ... all the ioctls which don't
	 * follow the new unique numbering scheme are deprecated */
	switch (cmd) {
	case SCSI_IOCTL_SEND_COMMAND:
	case SCSI_IOCTL_TEST_UNIT_READY:
	case SCSI_IOCTL_BENCHMARK_COMMAND:
	case SCSI_IOCTL_SYNC:
	case SCSI_IOCTL_START_UNIT:
	case SCSI_IOCTL_STOP_UNIT:
		printk(KERN_WARNING "program %s is using a deprecated SCSI "
		       "ioctl, please convert it to SG_IO\n", current->comm);
		break;
	default:
		break;
	}

	switch (cmd) {
	case SG_GET_VERSION_NUM:
		return sg_get_version(arg);
	case SG_SET_TIMEOUT:
		return sg_set_timeout(sdev, arg);
	case SG_GET_TIMEOUT:
		return jiffies_to_clock_t(sdev->sg_timeout);
	case SG_GET_RESERVED_SIZE:
		return sg_get_reserved_size(sdev, arg);
	case SG_SET_RESERVED_SIZE:
		return sg_set_reserved_size(sdev, arg);
	case SG_EMULATED_HOST:
		return sg_emulated_host(q, arg);
	case SG_IO:
		return scsi_ioctl_sg_io(sdev, open_for_write, arg);
	case SCSI_IOCTL_SEND_COMMAND:
		return sg_scsi_ioctl(q, open_for_write, arg);
	case CDROM_SEND_PACKET:
		return scsi_cdrom_send_packet(sdev, open_for_write, arg);
	case CDROMCLOSETRAY:
		return scsi_send_start_stop(sdev, 3);
	case CDROMEJECT:
		return scsi_send_start_stop(sdev, 2);
	case SCSI_IOCTL_GET_IDLUN:
		return scsi_get_idlun(sdev, arg);
	case SCSI_IOCTL_GET_BUS_NUMBER:
		return put_user(sdev->host->host_no, (int __user *)arg);
	case SCSI_IOCTL_PROBE_HOST:
		return ioctl_probe(sdev->host, arg);
	case SCSI_IOCTL_DOORLOCK:
		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
	case SCSI_IOCTL_DOORUNLOCK:
		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
	case SCSI_IOCTL_TEST_UNIT_READY:
		return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
					    NORMAL_RETRIES, &sense_hdr);
	case SCSI_IOCTL_START_UNIT:
		return scsi_send_start_stop(sdev, 1);
	case SCSI_IOCTL_STOP_UNIT:
		return scsi_send_start_stop(sdev, 0);
        case SCSI_IOCTL_GET_PCI:
                return scsi_ioctl_get_pci(sdev, arg);
	case SG_SCSI_RESET:
		return scsi_ioctl_reset(sdev, arg);
	}

#ifdef CONFIG_COMPAT
	if (in_compat_syscall()) {
		if (!sdev->host->hostt->compat_ioctl)
			return -EINVAL;
		return sdev->host->hostt->compat_ioctl(sdev, cmd, arg);
	}
#endif
	if (!sdev->host->hostt->ioctl)
		return -EINVAL;
	return sdev->host->hostt->ioctl(sdev, cmd, arg);
}
EXPORT_SYMBOL(scsi_ioctl);

/*
 * We can process a reset even when a device isn't fully operable.
 */
int scsi_ioctl_block_when_processing_errors(struct scsi_device *sdev, int cmd,
		bool ndelay)
{
	if (cmd == SG_SCSI_RESET && ndelay) {
		if (scsi_host_in_recovery(sdev->host))
			return -EAGAIN;
	} else {
		if (!scsi_block_when_processing_errors(sdev))
			return -ENODEV;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(scsi_ioctl_block_when_processing_errors);