xref: /openbmc/linux/drivers/scsi/scsi_ioctl.c (revision 7a010c3c)
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 (copy_from_user(req->cmd, hdr->cmdp, hdr->cmd_len))
351 		return -EFAULT;
352 	if (!scsi_cmd_allowed(req->cmd, mode))
353 		return -EPERM;
354 
355 	/*
356 	 * fill in request structure
357 	 */
358 	req->cmd_len = hdr->cmd_len;
359 
360 	rq->timeout = msecs_to_jiffies(hdr->timeout);
361 	if (!rq->timeout)
362 		rq->timeout = sdev->sg_timeout;
363 	if (!rq->timeout)
364 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
365 	if (rq->timeout < BLK_MIN_SG_TIMEOUT)
366 		rq->timeout = BLK_MIN_SG_TIMEOUT;
367 
368 	return 0;
369 }
370 
371 static int scsi_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
372 		struct bio *bio)
373 {
374 	struct scsi_request *req = scsi_req(rq);
375 	int r, ret = 0;
376 
377 	/*
378 	 * fill in all the output members
379 	 */
380 	hdr->status = req->result & 0xff;
381 	hdr->masked_status = status_byte(req->result);
382 	hdr->msg_status = COMMAND_COMPLETE;
383 	hdr->host_status = host_byte(req->result);
384 	hdr->driver_status = 0;
385 	if (scsi_status_is_check_condition(hdr->status))
386 		hdr->driver_status = DRIVER_SENSE;
387 	hdr->info = 0;
388 	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
389 		hdr->info |= SG_INFO_CHECK;
390 	hdr->resid = req->resid_len;
391 	hdr->sb_len_wr = 0;
392 
393 	if (req->sense_len && hdr->sbp) {
394 		int len = min((unsigned int) hdr->mx_sb_len, req->sense_len);
395 
396 		if (!copy_to_user(hdr->sbp, req->sense, len))
397 			hdr->sb_len_wr = len;
398 		else
399 			ret = -EFAULT;
400 	}
401 
402 	r = blk_rq_unmap_user(bio);
403 	if (!ret)
404 		ret = r;
405 
406 	return ret;
407 }
408 
409 static int sg_io(struct scsi_device *sdev, struct gendisk *disk,
410 		struct sg_io_hdr *hdr, fmode_t mode)
411 {
412 	unsigned long start_time;
413 	ssize_t ret = 0;
414 	int writing = 0;
415 	int at_head = 0;
416 	struct request *rq;
417 	struct scsi_request *req;
418 	struct bio *bio;
419 
420 	if (hdr->interface_id != 'S')
421 		return -EINVAL;
422 
423 	if (hdr->dxfer_len > (queue_max_hw_sectors(sdev->request_queue) << 9))
424 		return -EIO;
425 
426 	if (hdr->dxfer_len)
427 		switch (hdr->dxfer_direction) {
428 		default:
429 			return -EINVAL;
430 		case SG_DXFER_TO_DEV:
431 			writing = 1;
432 			break;
433 		case SG_DXFER_TO_FROM_DEV:
434 		case SG_DXFER_FROM_DEV:
435 			break;
436 		}
437 	if (hdr->flags & SG_FLAG_Q_AT_HEAD)
438 		at_head = 1;
439 
440 	ret = -ENOMEM;
441 	rq = blk_get_request(sdev->request_queue, writing ?
442 			     REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
443 	if (IS_ERR(rq))
444 		return PTR_ERR(rq);
445 	req = scsi_req(rq);
446 
447 	if (hdr->cmd_len > BLK_MAX_CDB) {
448 		req->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
449 		if (!req->cmd)
450 			goto out_put_request;
451 	}
452 
453 	ret = scsi_fill_sghdr_rq(sdev, rq, hdr, mode);
454 	if (ret < 0)
455 		goto out_free_cdb;
456 
457 	ret = 0;
458 	if (hdr->iovec_count) {
459 		struct iov_iter i;
460 		struct iovec *iov = NULL;
461 
462 		ret = import_iovec(rq_data_dir(rq), hdr->dxferp,
463 				   hdr->iovec_count, 0, &iov, &i);
464 		if (ret < 0)
465 			goto out_free_cdb;
466 
467 		/* SG_IO howto says that the shorter of the two wins */
468 		iov_iter_truncate(&i, hdr->dxfer_len);
469 
470 		ret = blk_rq_map_user_iov(rq->q, rq, NULL, &i, GFP_KERNEL);
471 		kfree(iov);
472 	} else if (hdr->dxfer_len)
473 		ret = blk_rq_map_user(rq->q, rq, NULL, hdr->dxferp,
474 				      hdr->dxfer_len, GFP_KERNEL);
475 
476 	if (ret)
477 		goto out_free_cdb;
478 
479 	bio = rq->bio;
480 	req->retries = 0;
481 
482 	start_time = jiffies;
483 
484 	blk_execute_rq(disk, rq, at_head);
485 
486 	hdr->duration = jiffies_to_msecs(jiffies - start_time);
487 
488 	ret = scsi_complete_sghdr_rq(rq, hdr, bio);
489 
490 out_free_cdb:
491 	scsi_req_free_cmd(req);
492 out_put_request:
493 	blk_put_request(rq);
494 	return ret;
495 }
496 
497 /**
498  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
499  * @q:		request queue to send scsi commands down
500  * @disk:	gendisk to operate on (option)
501  * @mode:	mode used to open the file through which the ioctl has been
502  *		submitted
503  * @sic:	userspace structure describing the command to perform
504  *
505  * Send down the scsi command described by @sic to the device below
506  * the request queue @q.  If @file is non-NULL it's used to perform
507  * fine-grained permission checks that allow users to send down
508  * non-destructive SCSI commands.  If the caller has a struct gendisk
509  * available it should be passed in as @disk to allow the low level
510  * driver to use the information contained in it.  A non-NULL @disk
511  * is only allowed if the caller knows that the low level driver doesn't
512  * need it (e.g. in the scsi subsystem).
513  *
514  * Notes:
515  *   -  This interface is deprecated - users should use the SG_IO
516  *      interface instead, as this is a more flexible approach to
517  *      performing SCSI commands on a device.
518  *   -  The SCSI command length is determined by examining the 1st byte
519  *      of the given command. There is no way to override this.
520  *   -  Data transfers are limited to PAGE_SIZE
521  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
522  *      accommodate the sense buffer when an error occurs.
523  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
524  *      old code will not be surprised.
525  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
526  *      a negative return and the Unix error code in 'errno'.
527  *      If the SCSI command succeeds then 0 is returned.
528  *      Positive numbers returned are the compacted SCSI error codes (4
529  *      bytes in one int) where the lowest byte is the SCSI status.
530  */
531 static int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk,
532 		fmode_t mode, struct scsi_ioctl_command __user *sic)
533 {
534 	enum { OMAX_SB_LEN = 16 };	/* For backward compatibility */
535 	struct request *rq;
536 	struct scsi_request *req;
537 	int err;
538 	unsigned int in_len, out_len, bytes, opcode, cmdlen;
539 	char *buffer = NULL;
540 
541 	if (!sic)
542 		return -EINVAL;
543 
544 	/*
545 	 * get in an out lengths, verify they don't exceed a page worth of data
546 	 */
547 	if (get_user(in_len, &sic->inlen))
548 		return -EFAULT;
549 	if (get_user(out_len, &sic->outlen))
550 		return -EFAULT;
551 	if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
552 		return -EINVAL;
553 	if (get_user(opcode, sic->data))
554 		return -EFAULT;
555 
556 	bytes = max(in_len, out_len);
557 	if (bytes) {
558 		buffer = kzalloc(bytes, GFP_NOIO | GFP_USER | __GFP_NOWARN);
559 		if (!buffer)
560 			return -ENOMEM;
561 
562 	}
563 
564 	rq = blk_get_request(q, in_len ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
565 	if (IS_ERR(rq)) {
566 		err = PTR_ERR(rq);
567 		goto error_free_buffer;
568 	}
569 	req = scsi_req(rq);
570 
571 	cmdlen = COMMAND_SIZE(opcode);
572 
573 	/*
574 	 * get command and data to send to device, if any
575 	 */
576 	err = -EFAULT;
577 	req->cmd_len = cmdlen;
578 	if (copy_from_user(req->cmd, sic->data, cmdlen))
579 		goto error;
580 
581 	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
582 		goto error;
583 
584 	err = -EPERM;
585 	if (!scsi_cmd_allowed(req->cmd, mode))
586 		goto error;
587 
588 	/* default.  possible overridden later */
589 	req->retries = 5;
590 
591 	switch (opcode) {
592 	case SEND_DIAGNOSTIC:
593 	case FORMAT_UNIT:
594 		rq->timeout = FORMAT_UNIT_TIMEOUT;
595 		req->retries = 1;
596 		break;
597 	case START_STOP:
598 		rq->timeout = START_STOP_TIMEOUT;
599 		break;
600 	case MOVE_MEDIUM:
601 		rq->timeout = MOVE_MEDIUM_TIMEOUT;
602 		break;
603 	case READ_ELEMENT_STATUS:
604 		rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
605 		break;
606 	case READ_DEFECT_DATA:
607 		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
608 		req->retries = 1;
609 		break;
610 	default:
611 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
612 		break;
613 	}
614 
615 	if (bytes) {
616 		err = blk_rq_map_kern(q, rq, buffer, bytes, GFP_NOIO);
617 		if (err)
618 			goto error;
619 	}
620 
621 	blk_execute_rq(disk, rq, 0);
622 
623 	err = req->result & 0xff;	/* only 8 bit SCSI status */
624 	if (err) {
625 		if (req->sense_len && req->sense) {
626 			bytes = (OMAX_SB_LEN > req->sense_len) ?
627 				req->sense_len : OMAX_SB_LEN;
628 			if (copy_to_user(sic->data, req->sense, bytes))
629 				err = -EFAULT;
630 		}
631 	} else {
632 		if (copy_to_user(sic->data, buffer, out_len))
633 			err = -EFAULT;
634 	}
635 
636 error:
637 	blk_put_request(rq);
638 
639 error_free_buffer:
640 	kfree(buffer);
641 
642 	return err;
643 }
644 
645 int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp)
646 {
647 #ifdef CONFIG_COMPAT
648 	if (in_compat_syscall()) {
649 		struct compat_sg_io_hdr hdr32 =  {
650 			.interface_id	 = hdr->interface_id,
651 			.dxfer_direction = hdr->dxfer_direction,
652 			.cmd_len	 = hdr->cmd_len,
653 			.mx_sb_len	 = hdr->mx_sb_len,
654 			.iovec_count	 = hdr->iovec_count,
655 			.dxfer_len	 = hdr->dxfer_len,
656 			.dxferp		 = (uintptr_t)hdr->dxferp,
657 			.cmdp		 = (uintptr_t)hdr->cmdp,
658 			.sbp		 = (uintptr_t)hdr->sbp,
659 			.timeout	 = hdr->timeout,
660 			.flags		 = hdr->flags,
661 			.pack_id	 = hdr->pack_id,
662 			.usr_ptr	 = (uintptr_t)hdr->usr_ptr,
663 			.status		 = hdr->status,
664 			.masked_status	 = hdr->masked_status,
665 			.msg_status	 = hdr->msg_status,
666 			.sb_len_wr	 = hdr->sb_len_wr,
667 			.host_status	 = hdr->host_status,
668 			.driver_status	 = hdr->driver_status,
669 			.resid		 = hdr->resid,
670 			.duration	 = hdr->duration,
671 			.info		 = hdr->info,
672 		};
673 
674 		if (copy_to_user(argp, &hdr32, sizeof(hdr32)))
675 			return -EFAULT;
676 
677 		return 0;
678 	}
679 #endif
680 
681 	if (copy_to_user(argp, hdr, sizeof(*hdr)))
682 		return -EFAULT;
683 
684 	return 0;
685 }
686 EXPORT_SYMBOL(put_sg_io_hdr);
687 
688 int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp)
689 {
690 #ifdef CONFIG_COMPAT
691 	struct compat_sg_io_hdr hdr32;
692 
693 	if (in_compat_syscall()) {
694 		if (copy_from_user(&hdr32, argp, sizeof(hdr32)))
695 			return -EFAULT;
696 
697 		*hdr = (struct sg_io_hdr) {
698 			.interface_id	 = hdr32.interface_id,
699 			.dxfer_direction = hdr32.dxfer_direction,
700 			.cmd_len	 = hdr32.cmd_len,
701 			.mx_sb_len	 = hdr32.mx_sb_len,
702 			.iovec_count	 = hdr32.iovec_count,
703 			.dxfer_len	 = hdr32.dxfer_len,
704 			.dxferp		 = compat_ptr(hdr32.dxferp),
705 			.cmdp		 = compat_ptr(hdr32.cmdp),
706 			.sbp		 = compat_ptr(hdr32.sbp),
707 			.timeout	 = hdr32.timeout,
708 			.flags		 = hdr32.flags,
709 			.pack_id	 = hdr32.pack_id,
710 			.usr_ptr	 = compat_ptr(hdr32.usr_ptr),
711 			.status		 = hdr32.status,
712 			.masked_status	 = hdr32.masked_status,
713 			.msg_status	 = hdr32.msg_status,
714 			.sb_len_wr	 = hdr32.sb_len_wr,
715 			.host_status	 = hdr32.host_status,
716 			.driver_status	 = hdr32.driver_status,
717 			.resid		 = hdr32.resid,
718 			.duration	 = hdr32.duration,
719 			.info		 = hdr32.info,
720 		};
721 
722 		return 0;
723 	}
724 #endif
725 
726 	if (copy_from_user(hdr, argp, sizeof(*hdr)))
727 		return -EFAULT;
728 
729 	return 0;
730 }
731 EXPORT_SYMBOL(get_sg_io_hdr);
732 
733 #ifdef CONFIG_COMPAT
734 struct compat_cdrom_generic_command {
735 	unsigned char	cmd[CDROM_PACKET_SIZE];
736 	compat_caddr_t	buffer;
737 	compat_uint_t	buflen;
738 	compat_int_t	stat;
739 	compat_caddr_t	sense;
740 	unsigned char	data_direction;
741 	unsigned char	pad[3];
742 	compat_int_t	quiet;
743 	compat_int_t	timeout;
744 	compat_caddr_t	unused;
745 };
746 #endif
747 
748 static int scsi_get_cdrom_generic_arg(struct cdrom_generic_command *cgc,
749 				      const void __user *arg)
750 {
751 #ifdef CONFIG_COMPAT
752 	if (in_compat_syscall()) {
753 		struct compat_cdrom_generic_command cgc32;
754 
755 		if (copy_from_user(&cgc32, arg, sizeof(cgc32)))
756 			return -EFAULT;
757 
758 		*cgc = (struct cdrom_generic_command) {
759 			.buffer		= compat_ptr(cgc32.buffer),
760 			.buflen		= cgc32.buflen,
761 			.stat		= cgc32.stat,
762 			.sense		= compat_ptr(cgc32.sense),
763 			.data_direction	= cgc32.data_direction,
764 			.quiet		= cgc32.quiet,
765 			.timeout	= cgc32.timeout,
766 			.unused		= compat_ptr(cgc32.unused),
767 		};
768 		memcpy(&cgc->cmd, &cgc32.cmd, CDROM_PACKET_SIZE);
769 		return 0;
770 	}
771 #endif
772 	if (copy_from_user(cgc, arg, sizeof(*cgc)))
773 		return -EFAULT;
774 
775 	return 0;
776 }
777 
778 static int scsi_put_cdrom_generic_arg(const struct cdrom_generic_command *cgc,
779 				      void __user *arg)
780 {
781 #ifdef CONFIG_COMPAT
782 	if (in_compat_syscall()) {
783 		struct compat_cdrom_generic_command cgc32 = {
784 			.buffer		= (uintptr_t)(cgc->buffer),
785 			.buflen		= cgc->buflen,
786 			.stat		= cgc->stat,
787 			.sense		= (uintptr_t)(cgc->sense),
788 			.data_direction	= cgc->data_direction,
789 			.quiet		= cgc->quiet,
790 			.timeout	= cgc->timeout,
791 			.unused		= (uintptr_t)(cgc->unused),
792 		};
793 		memcpy(&cgc32.cmd, &cgc->cmd, CDROM_PACKET_SIZE);
794 
795 		if (copy_to_user(arg, &cgc32, sizeof(cgc32)))
796 			return -EFAULT;
797 
798 		return 0;
799 	}
800 #endif
801 	if (copy_to_user(arg, cgc, sizeof(*cgc)))
802 		return -EFAULT;
803 
804 	return 0;
805 }
806 
807 static int scsi_cdrom_send_packet(struct scsi_device *sdev, struct gendisk *disk,
808 		fmode_t mode, void __user *arg)
809 {
810 	struct cdrom_generic_command cgc;
811 	struct sg_io_hdr hdr;
812 	int err;
813 
814 	err = scsi_get_cdrom_generic_arg(&cgc, arg);
815 	if (err)
816 		return err;
817 
818 	cgc.timeout = clock_t_to_jiffies(cgc.timeout);
819 	memset(&hdr, 0, sizeof(hdr));
820 	hdr.interface_id = 'S';
821 	hdr.cmd_len = sizeof(cgc.cmd);
822 	hdr.dxfer_len = cgc.buflen;
823 	switch (cgc.data_direction) {
824 	case CGC_DATA_UNKNOWN:
825 		hdr.dxfer_direction = SG_DXFER_UNKNOWN;
826 		break;
827 	case CGC_DATA_WRITE:
828 		hdr.dxfer_direction = SG_DXFER_TO_DEV;
829 		break;
830 	case CGC_DATA_READ:
831 		hdr.dxfer_direction = SG_DXFER_FROM_DEV;
832 		break;
833 	case CGC_DATA_NONE:
834 		hdr.dxfer_direction = SG_DXFER_NONE;
835 		break;
836 	default:
837 		return -EINVAL;
838 	}
839 
840 	hdr.dxferp = cgc.buffer;
841 	hdr.sbp = cgc.sense;
842 	if (hdr.sbp)
843 		hdr.mx_sb_len = sizeof(struct request_sense);
844 	hdr.timeout = jiffies_to_msecs(cgc.timeout);
845 	hdr.cmdp = ((struct cdrom_generic_command __user *) arg)->cmd;
846 	hdr.cmd_len = sizeof(cgc.cmd);
847 
848 	err = sg_io(sdev, disk, &hdr, mode);
849 	if (err == -EFAULT)
850 		return -EFAULT;
851 
852 	if (hdr.status)
853 		return -EIO;
854 
855 	cgc.stat = err;
856 	cgc.buflen = hdr.resid;
857 	if (scsi_put_cdrom_generic_arg(&cgc, arg))
858 		return -EFAULT;
859 
860 	return err;
861 }
862 
863 static int scsi_ioctl_sg_io(struct scsi_device *sdev, struct gendisk *disk,
864 		fmode_t mode, void __user *argp)
865 {
866 	struct sg_io_hdr hdr;
867 	int error;
868 
869 	error = get_sg_io_hdr(&hdr, argp);
870 	if (error)
871 		return error;
872 	error = sg_io(sdev, disk, &hdr, mode);
873 	if (error == -EFAULT)
874 		return error;
875 	if (put_sg_io_hdr(&hdr, argp))
876 		return -EFAULT;
877 	return error;
878 }
879 
880 /**
881  * scsi_ioctl - Dispatch ioctl to scsi device
882  * @sdev: scsi device receiving ioctl
883  * @disk: disk receiving the ioctl
884  * @mode: mode the block/char device is opened with
885  * @cmd: which ioctl is it
886  * @arg: data associated with ioctl
887  *
888  * Description: The scsi_ioctl() function differs from most ioctls in that it
889  * does not take a major/minor number as the dev field.  Rather, it takes
890  * a pointer to a &struct scsi_device.
891  */
892 int scsi_ioctl(struct scsi_device *sdev, struct gendisk *disk, fmode_t mode,
893 		int cmd, void __user *arg)
894 {
895 	struct request_queue *q = sdev->request_queue;
896 	struct scsi_sense_hdr sense_hdr;
897 
898 	/* Check for deprecated ioctls ... all the ioctls which don't
899 	 * follow the new unique numbering scheme are deprecated */
900 	switch (cmd) {
901 	case SCSI_IOCTL_SEND_COMMAND:
902 	case SCSI_IOCTL_TEST_UNIT_READY:
903 	case SCSI_IOCTL_BENCHMARK_COMMAND:
904 	case SCSI_IOCTL_SYNC:
905 	case SCSI_IOCTL_START_UNIT:
906 	case SCSI_IOCTL_STOP_UNIT:
907 		printk(KERN_WARNING "program %s is using a deprecated SCSI "
908 		       "ioctl, please convert it to SG_IO\n", current->comm);
909 		break;
910 	default:
911 		break;
912 	}
913 
914 	switch (cmd) {
915 	case SG_GET_VERSION_NUM:
916 		return sg_get_version(arg);
917 	case SG_SET_TIMEOUT:
918 		return sg_set_timeout(sdev, arg);
919 	case SG_GET_TIMEOUT:
920 		return jiffies_to_clock_t(sdev->sg_timeout);
921 	case SG_GET_RESERVED_SIZE:
922 		return sg_get_reserved_size(sdev, arg);
923 	case SG_SET_RESERVED_SIZE:
924 		return sg_set_reserved_size(sdev, arg);
925 	case SG_EMULATED_HOST:
926 		return sg_emulated_host(q, arg);
927 	case SG_IO:
928 		return scsi_ioctl_sg_io(sdev, disk, mode, arg);
929 	case SCSI_IOCTL_SEND_COMMAND:
930 		return sg_scsi_ioctl(q, disk, mode, arg);
931 	case CDROM_SEND_PACKET:
932 		return scsi_cdrom_send_packet(sdev, disk, mode, arg);
933 	case CDROMCLOSETRAY:
934 		return scsi_send_start_stop(sdev, 3);
935 	case CDROMEJECT:
936 		return scsi_send_start_stop(sdev, 2);
937 	case SCSI_IOCTL_GET_IDLUN:
938 		return scsi_get_idlun(sdev, arg);
939 	case SCSI_IOCTL_GET_BUS_NUMBER:
940 		return put_user(sdev->host->host_no, (int __user *)arg);
941 	case SCSI_IOCTL_PROBE_HOST:
942 		return ioctl_probe(sdev->host, arg);
943 	case SCSI_IOCTL_DOORLOCK:
944 		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
945 	case SCSI_IOCTL_DOORUNLOCK:
946 		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
947 	case SCSI_IOCTL_TEST_UNIT_READY:
948 		return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
949 					    NORMAL_RETRIES, &sense_hdr);
950 	case SCSI_IOCTL_START_UNIT:
951 		return scsi_send_start_stop(sdev, 1);
952 	case SCSI_IOCTL_STOP_UNIT:
953 		return scsi_send_start_stop(sdev, 0);
954         case SCSI_IOCTL_GET_PCI:
955                 return scsi_ioctl_get_pci(sdev, arg);
956 	case SG_SCSI_RESET:
957 		return scsi_ioctl_reset(sdev, arg);
958 	}
959 
960 #ifdef CONFIG_COMPAT
961 	if (in_compat_syscall()) {
962 		if (!sdev->host->hostt->compat_ioctl)
963 			return -EINVAL;
964 		return sdev->host->hostt->compat_ioctl(sdev, cmd, arg);
965 	}
966 #endif
967 	if (!sdev->host->hostt->ioctl)
968 		return -EINVAL;
969 	return sdev->host->hostt->ioctl(sdev, cmd, arg);
970 }
971 EXPORT_SYMBOL(scsi_ioctl);
972 
973 /*
974  * We can process a reset even when a device isn't fully operable.
975  */
976 int scsi_ioctl_block_when_processing_errors(struct scsi_device *sdev, int cmd,
977 		bool ndelay)
978 {
979 	if (cmd == SG_SCSI_RESET && ndelay) {
980 		if (scsi_host_in_recovery(sdev->host))
981 			return -EAGAIN;
982 	} else {
983 		if (!scsi_block_when_processing_errors(sdev))
984 			return -ENODEV;
985 	}
986 
987 	return 0;
988 }
989 EXPORT_SYMBOL_GPL(scsi_ioctl_block_when_processing_errors);
990