xref: /linux/drivers/scsi/scsi_ioctl.c (revision 55f1b540d893da740a81200450014c45a8103f54)
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 	const struct scsi_exec_args exec_args = {
73 		.sshdr = &sshdr,
74 	};
75 
76 	SCSI_LOG_IOCTL(1, sdev_printk(KERN_INFO, sdev,
77 				      "Trying ioctl with scsi command %d\n", *cmd));
78 
79 	result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, NULL, 0, timeout,
80 				  retries, &exec_args);
81 
82 	SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
83 				      "Ioctl returned  0x%x\n", result));
84 
85 	if (result < 0)
86 		goto out;
87 	if (scsi_sense_valid(&sshdr)) {
88 		switch (sshdr.sense_key) {
89 		case ILLEGAL_REQUEST:
90 			if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
91 				sdev->lockable = 0;
92 			else
93 				sdev_printk(KERN_INFO, sdev,
94 					    "ioctl_internal_command: "
95 					    "ILLEGAL REQUEST "
96 					    "asc=0x%x ascq=0x%x\n",
97 					    sshdr.asc, sshdr.ascq);
98 			break;
99 		case NOT_READY:	/* This happens if there is no disc in drive */
100 			if (sdev->removable)
101 				break;
102 			fallthrough;
103 		case UNIT_ATTENTION:
104 			if (sdev->removable) {
105 				sdev->changed = 1;
106 				result = 0;	/* This is no longer considered an error */
107 				break;
108 			}
109 			fallthrough;	/* for non-removable media */
110 		default:
111 			sdev_printk(KERN_INFO, sdev,
112 				    "ioctl_internal_command return code = %x\n",
113 				    result);
114 			scsi_print_sense_hdr(sdev, NULL, &sshdr);
115 			break;
116 		}
117 	}
118 out:
119 	SCSI_LOG_IOCTL(2, sdev_printk(KERN_INFO, sdev,
120 				      "IOCTL Releasing command\n"));
121 	return result;
122 }
123 
124 int scsi_set_medium_removal(struct scsi_device *sdev, char state)
125 {
126 	char scsi_cmd[MAX_COMMAND_SIZE];
127 	int ret;
128 
129 	if (!sdev->removable || !sdev->lockable)
130 	       return 0;
131 
132 	scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
133 	scsi_cmd[1] = 0;
134 	scsi_cmd[2] = 0;
135 	scsi_cmd[3] = 0;
136 	scsi_cmd[4] = state;
137 	scsi_cmd[5] = 0;
138 
139 	ret = ioctl_internal_command(sdev, scsi_cmd,
140 			IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
141 	if (ret == 0)
142 		sdev->locked = (state == SCSI_REMOVAL_PREVENT);
143 	return ret;
144 }
145 EXPORT_SYMBOL(scsi_set_medium_removal);
146 
147 /*
148  * The scsi_ioctl_get_pci() function places into arg the value
149  * pci_dev::slot_name (8 characters) for the PCI device (if any).
150  * Returns: 0 on success
151  *          -ENXIO if there isn't a PCI device pointer
152  *                 (could be because the SCSI driver hasn't been
153  *                  updated yet, or because it isn't a SCSI
154  *                  device)
155  *          any copy_to_user() error on failure there
156  */
157 static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg)
158 {
159 	struct device *dev = scsi_get_device(sdev->host);
160 	const char *name;
161 
162         if (!dev)
163 		return -ENXIO;
164 
165 	name = dev_name(dev);
166 
167 	/* compatibility with old ioctl which only returned
168 	 * 20 characters */
169         return copy_to_user(arg, name, min(strlen(name), (size_t)20))
170 		? -EFAULT: 0;
171 }
172 
173 static int sg_get_version(int __user *p)
174 {
175 	static const int sg_version_num = 30527;
176 	return put_user(sg_version_num, p);
177 }
178 
179 static int sg_set_timeout(struct scsi_device *sdev, int __user *p)
180 {
181 	int timeout, err = get_user(timeout, p);
182 
183 	if (!err)
184 		sdev->sg_timeout = clock_t_to_jiffies(timeout);
185 
186 	return err;
187 }
188 
189 static int sg_get_reserved_size(struct scsi_device *sdev, int __user *p)
190 {
191 	int val = min(sdev->sg_reserved_size,
192 		      queue_max_bytes(sdev->request_queue));
193 
194 	return put_user(val, p);
195 }
196 
197 static int sg_set_reserved_size(struct scsi_device *sdev, int __user *p)
198 {
199 	int size, err = get_user(size, p);
200 
201 	if (err)
202 		return err;
203 
204 	if (size < 0)
205 		return -EINVAL;
206 
207 	sdev->sg_reserved_size = min_t(unsigned int, size,
208 				       queue_max_bytes(sdev->request_queue));
209 	return 0;
210 }
211 
212 /*
213  * will always return that we are ATAPI even for a real SCSI drive, I'm not
214  * so sure this is worth doing anything about (why would you care??)
215  */
216 static int sg_emulated_host(struct request_queue *q, int __user *p)
217 {
218 	return put_user(1, p);
219 }
220 
221 static int scsi_get_idlun(struct scsi_device *sdev, void __user *argp)
222 {
223 	struct scsi_idlun v = {
224 		.dev_id = (sdev->id & 0xff) +
225 			((sdev->lun & 0xff) << 8) +
226 			((sdev->channel & 0xff) << 16) +
227 			((sdev->host->host_no & 0xff) << 24),
228 		.host_unique_id = sdev->host->unique_id
229 	};
230 	if (copy_to_user(argp, &v, sizeof(struct scsi_idlun)))
231 		return -EFAULT;
232 	return 0;
233 }
234 
235 static int scsi_send_start_stop(struct scsi_device *sdev, int data)
236 {
237 	u8 cdb[MAX_COMMAND_SIZE] = { };
238 
239 	cdb[0] = START_STOP;
240 	cdb[4] = data;
241 	return ioctl_internal_command(sdev, cdb, START_STOP_TIMEOUT,
242 				      NORMAL_RETRIES);
243 }
244 
245 /*
246  * Check if the given command is allowed.
247  *
248  * Only a subset of commands are allowed for unprivileged users. Commands used
249  * to format the media, update the firmware, etc. are not permitted.
250  */
251 bool scsi_cmd_allowed(unsigned char *cmd, bool open_for_write)
252 {
253 	/* root can do any command. */
254 	if (capable(CAP_SYS_RAWIO))
255 		return true;
256 
257 	/* Anybody who can open the device can do a read-safe command */
258 	switch (cmd[0]) {
259 	/* Basic read-only commands */
260 	case TEST_UNIT_READY:
261 	case REQUEST_SENSE:
262 	case READ_6:
263 	case READ_10:
264 	case READ_12:
265 	case READ_16:
266 	case READ_BUFFER:
267 	case READ_DEFECT_DATA:
268 	case READ_CAPACITY: /* also GPCMD_READ_CDVD_CAPACITY */
269 	case READ_LONG:
270 	case INQUIRY:
271 	case MODE_SENSE:
272 	case MODE_SENSE_10:
273 	case LOG_SENSE:
274 	case START_STOP:
275 	case GPCMD_VERIFY_10:
276 	case VERIFY_16:
277 	case REPORT_LUNS:
278 	case SERVICE_ACTION_IN_16:
279 	case RECEIVE_DIAGNOSTIC:
280 	case MAINTENANCE_IN: /* also GPCMD_SEND_KEY, which is a write command */
281 	case GPCMD_READ_BUFFER_CAPACITY:
282 	/* Audio CD commands */
283 	case GPCMD_PLAY_CD:
284 	case GPCMD_PLAY_AUDIO_10:
285 	case GPCMD_PLAY_AUDIO_MSF:
286 	case GPCMD_PLAY_AUDIO_TI:
287 	case GPCMD_PAUSE_RESUME:
288 	/* CD/DVD data reading */
289 	case GPCMD_READ_CD:
290 	case GPCMD_READ_CD_MSF:
291 	case GPCMD_READ_DISC_INFO:
292 	case GPCMD_READ_DVD_STRUCTURE:
293 	case GPCMD_READ_HEADER:
294 	case GPCMD_READ_TRACK_RZONE_INFO:
295 	case GPCMD_READ_SUBCHANNEL:
296 	case GPCMD_READ_TOC_PMA_ATIP:
297 	case GPCMD_REPORT_KEY:
298 	case GPCMD_SCAN:
299 	case GPCMD_GET_CONFIGURATION:
300 	case GPCMD_READ_FORMAT_CAPACITIES:
301 	case GPCMD_GET_EVENT_STATUS_NOTIFICATION:
302 	case GPCMD_GET_PERFORMANCE:
303 	case GPCMD_SEEK:
304 	case GPCMD_STOP_PLAY_SCAN:
305 	/* ZBC */
306 	case ZBC_IN:
307 		return true;
308 	/* Basic writing commands */
309 	case WRITE_6:
310 	case WRITE_10:
311 	case WRITE_VERIFY:
312 	case WRITE_12:
313 	case WRITE_VERIFY_12:
314 	case WRITE_16:
315 	case WRITE_LONG:
316 	case WRITE_LONG_2:
317 	case WRITE_SAME:
318 	case WRITE_SAME_16:
319 	case WRITE_SAME_32:
320 	case ERASE:
321 	case GPCMD_MODE_SELECT_10:
322 	case MODE_SELECT:
323 	case LOG_SELECT:
324 	case GPCMD_BLANK:
325 	case GPCMD_CLOSE_TRACK:
326 	case GPCMD_FLUSH_CACHE:
327 	case GPCMD_FORMAT_UNIT:
328 	case GPCMD_REPAIR_RZONE_TRACK:
329 	case GPCMD_RESERVE_RZONE_TRACK:
330 	case GPCMD_SEND_DVD_STRUCTURE:
331 	case GPCMD_SEND_EVENT:
332 	case GPCMD_SEND_OPC:
333 	case GPCMD_SEND_CUE_SHEET:
334 	case GPCMD_SET_SPEED:
335 	case GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
336 	case GPCMD_LOAD_UNLOAD:
337 	case GPCMD_SET_STREAMING:
338 	case GPCMD_SET_READ_AHEAD:
339 	/* ZBC */
340 	case ZBC_OUT:
341 		return open_for_write;
342 	default:
343 		return false;
344 	}
345 }
346 EXPORT_SYMBOL(scsi_cmd_allowed);
347 
348 static int scsi_fill_sghdr_rq(struct scsi_device *sdev, struct request *rq,
349 		struct sg_io_hdr *hdr, bool open_for_write)
350 {
351 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
352 
353 	if (hdr->cmd_len < 6)
354 		return -EMSGSIZE;
355 	if (copy_from_user(scmd->cmnd, hdr->cmdp, hdr->cmd_len))
356 		return -EFAULT;
357 	if (!scsi_cmd_allowed(scmd->cmnd, open_for_write))
358 		return -EPERM;
359 	scmd->cmd_len = hdr->cmd_len;
360 
361 	rq->timeout = msecs_to_jiffies(hdr->timeout);
362 	if (!rq->timeout)
363 		rq->timeout = sdev->sg_timeout;
364 	if (!rq->timeout)
365 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
366 	if (rq->timeout < BLK_MIN_SG_TIMEOUT)
367 		rq->timeout = BLK_MIN_SG_TIMEOUT;
368 
369 	return 0;
370 }
371 
372 static int scsi_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
373 		struct bio *bio)
374 {
375 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
376 	int r, ret = 0;
377 
378 	/*
379 	 * fill in all the output members
380 	 */
381 	hdr->status = scmd->result & 0xff;
382 	hdr->masked_status = sg_status_byte(scmd->result);
383 	hdr->msg_status = COMMAND_COMPLETE;
384 	hdr->host_status = host_byte(scmd->result);
385 	hdr->driver_status = 0;
386 	if (scsi_status_is_check_condition(hdr->status))
387 		hdr->driver_status = DRIVER_SENSE;
388 	hdr->info = 0;
389 	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
390 		hdr->info |= SG_INFO_CHECK;
391 	hdr->resid = scmd->resid_len;
392 	hdr->sb_len_wr = 0;
393 
394 	if (scmd->sense_len && hdr->sbp) {
395 		int len = min((unsigned int) hdr->mx_sb_len, scmd->sense_len);
396 
397 		if (!copy_to_user(hdr->sbp, scmd->sense_buffer, len))
398 			hdr->sb_len_wr = len;
399 		else
400 			ret = -EFAULT;
401 	}
402 
403 	r = blk_rq_unmap_user(bio);
404 	if (!ret)
405 		ret = r;
406 
407 	return ret;
408 }
409 
410 static int sg_io(struct scsi_device *sdev, struct sg_io_hdr *hdr,
411 		bool open_for_write)
412 {
413 	unsigned long start_time;
414 	ssize_t ret = 0;
415 	int writing = 0;
416 	int at_head = 0;
417 	struct request *rq;
418 	struct scsi_cmnd *scmd;
419 	struct bio *bio;
420 
421 	if (hdr->interface_id != 'S')
422 		return -EINVAL;
423 
424 	if (hdr->dxfer_len > (queue_max_hw_sectors(sdev->request_queue) << 9))
425 		return -EIO;
426 
427 	if (hdr->dxfer_len)
428 		switch (hdr->dxfer_direction) {
429 		default:
430 			return -EINVAL;
431 		case SG_DXFER_TO_DEV:
432 			writing = 1;
433 			break;
434 		case SG_DXFER_TO_FROM_DEV:
435 		case SG_DXFER_FROM_DEV:
436 			break;
437 		}
438 	if (hdr->flags & SG_FLAG_Q_AT_HEAD)
439 		at_head = 1;
440 
441 	rq = scsi_alloc_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 	scmd = blk_mq_rq_to_pdu(rq);
446 
447 	if (hdr->cmd_len > sizeof(scmd->cmnd)) {
448 		ret = -EINVAL;
449 		goto out_put_request;
450 	}
451 
452 	ret = scsi_fill_sghdr_rq(sdev, rq, hdr, open_for_write);
453 	if (ret < 0)
454 		goto out_put_request;
455 
456 	ret = blk_rq_map_user_io(rq, NULL, hdr->dxferp, hdr->dxfer_len,
457 			GFP_KERNEL, hdr->iovec_count && hdr->dxfer_len,
458 			hdr->iovec_count, 0, rq_data_dir(rq));
459 	if (ret)
460 		goto out_put_request;
461 
462 	bio = rq->bio;
463 	scmd->allowed = 0;
464 
465 	start_time = jiffies;
466 
467 	blk_execute_rq(rq, at_head);
468 
469 	hdr->duration = jiffies_to_msecs(jiffies - start_time);
470 
471 	ret = scsi_complete_sghdr_rq(rq, hdr, bio);
472 
473 out_put_request:
474 	blk_mq_free_request(rq);
475 	return ret;
476 }
477 
478 /**
479  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
480  * @q:		request queue to send scsi commands down
481  * @open_for_write: is the file / block device opened for writing?
482  * @sic:	userspace structure describing the command to perform
483  *
484  * Send down the scsi command described by @sic to the device below
485  * the request queue @q.
486  *
487  * Notes:
488  *   -  This interface is deprecated - users should use the SG_IO
489  *      interface instead, as this is a more flexible approach to
490  *      performing SCSI commands on a device.
491  *   -  The SCSI command length is determined by examining the 1st byte
492  *      of the given command. There is no way to override this.
493  *   -  Data transfers are limited to PAGE_SIZE
494  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
495  *      accommodate the sense buffer when an error occurs.
496  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
497  *      old code will not be surprised.
498  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
499  *      a negative return and the Unix error code in 'errno'.
500  *      If the SCSI command succeeds then 0 is returned.
501  *      Positive numbers returned are the compacted SCSI error codes (4
502  *      bytes in one int) where the lowest byte is the SCSI status.
503  */
504 static int sg_scsi_ioctl(struct request_queue *q, bool open_for_write,
505 		struct scsi_ioctl_command __user *sic)
506 {
507 	struct request *rq;
508 	int err;
509 	unsigned int in_len, out_len, bytes, opcode, cmdlen;
510 	struct scsi_cmnd *scmd;
511 	char *buffer = NULL;
512 
513 	if (!sic)
514 		return -EINVAL;
515 
516 	/*
517 	 * get in an out lengths, verify they don't exceed a page worth of data
518 	 */
519 	if (get_user(in_len, &sic->inlen))
520 		return -EFAULT;
521 	if (get_user(out_len, &sic->outlen))
522 		return -EFAULT;
523 	if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
524 		return -EINVAL;
525 	if (get_user(opcode, &sic->data[0]))
526 		return -EFAULT;
527 
528 	bytes = max(in_len, out_len);
529 	if (bytes) {
530 		buffer = kzalloc(bytes, GFP_NOIO | GFP_USER | __GFP_NOWARN);
531 		if (!buffer)
532 			return -ENOMEM;
533 
534 	}
535 
536 	rq = scsi_alloc_request(q, in_len ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
537 	if (IS_ERR(rq)) {
538 		err = PTR_ERR(rq);
539 		goto error_free_buffer;
540 	}
541 	scmd = blk_mq_rq_to_pdu(rq);
542 
543 	cmdlen = COMMAND_SIZE(opcode);
544 
545 	/*
546 	 * get command and data to send to device, if any
547 	 */
548 	err = -EFAULT;
549 	scmd->cmd_len = cmdlen;
550 	if (copy_from_user(scmd->cmnd, sic->data, cmdlen))
551 		goto error;
552 
553 	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
554 		goto error;
555 
556 	err = -EPERM;
557 	if (!scsi_cmd_allowed(scmd->cmnd, open_for_write))
558 		goto error;
559 
560 	/* default.  possible overridden later */
561 	scmd->allowed = 5;
562 
563 	switch (opcode) {
564 	case SEND_DIAGNOSTIC:
565 	case FORMAT_UNIT:
566 		rq->timeout = FORMAT_UNIT_TIMEOUT;
567 		scmd->allowed = 1;
568 		break;
569 	case START_STOP:
570 		rq->timeout = START_STOP_TIMEOUT;
571 		break;
572 	case MOVE_MEDIUM:
573 		rq->timeout = MOVE_MEDIUM_TIMEOUT;
574 		break;
575 	case READ_ELEMENT_STATUS:
576 		rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
577 		break;
578 	case READ_DEFECT_DATA:
579 		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
580 		scmd->allowed = 1;
581 		break;
582 	default:
583 		rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
584 		break;
585 	}
586 
587 	if (bytes) {
588 		err = blk_rq_map_kern(q, rq, buffer, bytes, GFP_NOIO);
589 		if (err)
590 			goto error;
591 	}
592 
593 	blk_execute_rq(rq, false);
594 
595 	err = scmd->result & 0xff;	/* only 8 bit SCSI status */
596 	if (err) {
597 		if (scmd->sense_len && scmd->sense_buffer) {
598 			/* limit sense len for backward compatibility */
599 			if (copy_to_user(sic->data, scmd->sense_buffer,
600 					 min(scmd->sense_len, 16U)))
601 				err = -EFAULT;
602 		}
603 	} else {
604 		if (copy_to_user(sic->data, buffer, out_len))
605 			err = -EFAULT;
606 	}
607 
608 error:
609 	blk_mq_free_request(rq);
610 
611 error_free_buffer:
612 	kfree(buffer);
613 
614 	return err;
615 }
616 
617 int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp)
618 {
619 #ifdef CONFIG_COMPAT
620 	if (in_compat_syscall()) {
621 		struct compat_sg_io_hdr hdr32 =  {
622 			.interface_id	 = hdr->interface_id,
623 			.dxfer_direction = hdr->dxfer_direction,
624 			.cmd_len	 = hdr->cmd_len,
625 			.mx_sb_len	 = hdr->mx_sb_len,
626 			.iovec_count	 = hdr->iovec_count,
627 			.dxfer_len	 = hdr->dxfer_len,
628 			.dxferp		 = (uintptr_t)hdr->dxferp,
629 			.cmdp		 = (uintptr_t)hdr->cmdp,
630 			.sbp		 = (uintptr_t)hdr->sbp,
631 			.timeout	 = hdr->timeout,
632 			.flags		 = hdr->flags,
633 			.pack_id	 = hdr->pack_id,
634 			.usr_ptr	 = (uintptr_t)hdr->usr_ptr,
635 			.status		 = hdr->status,
636 			.masked_status	 = hdr->masked_status,
637 			.msg_status	 = hdr->msg_status,
638 			.sb_len_wr	 = hdr->sb_len_wr,
639 			.host_status	 = hdr->host_status,
640 			.driver_status	 = hdr->driver_status,
641 			.resid		 = hdr->resid,
642 			.duration	 = hdr->duration,
643 			.info		 = hdr->info,
644 		};
645 
646 		if (copy_to_user(argp, &hdr32, sizeof(hdr32)))
647 			return -EFAULT;
648 
649 		return 0;
650 	}
651 #endif
652 
653 	if (copy_to_user(argp, hdr, sizeof(*hdr)))
654 		return -EFAULT;
655 
656 	return 0;
657 }
658 EXPORT_SYMBOL(put_sg_io_hdr);
659 
660 int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp)
661 {
662 #ifdef CONFIG_COMPAT
663 	struct compat_sg_io_hdr hdr32;
664 
665 	if (in_compat_syscall()) {
666 		if (copy_from_user(&hdr32, argp, sizeof(hdr32)))
667 			return -EFAULT;
668 
669 		*hdr = (struct sg_io_hdr) {
670 			.interface_id	 = hdr32.interface_id,
671 			.dxfer_direction = hdr32.dxfer_direction,
672 			.cmd_len	 = hdr32.cmd_len,
673 			.mx_sb_len	 = hdr32.mx_sb_len,
674 			.iovec_count	 = hdr32.iovec_count,
675 			.dxfer_len	 = hdr32.dxfer_len,
676 			.dxferp		 = compat_ptr(hdr32.dxferp),
677 			.cmdp		 = compat_ptr(hdr32.cmdp),
678 			.sbp		 = compat_ptr(hdr32.sbp),
679 			.timeout	 = hdr32.timeout,
680 			.flags		 = hdr32.flags,
681 			.pack_id	 = hdr32.pack_id,
682 			.usr_ptr	 = compat_ptr(hdr32.usr_ptr),
683 			.status		 = hdr32.status,
684 			.masked_status	 = hdr32.masked_status,
685 			.msg_status	 = hdr32.msg_status,
686 			.sb_len_wr	 = hdr32.sb_len_wr,
687 			.host_status	 = hdr32.host_status,
688 			.driver_status	 = hdr32.driver_status,
689 			.resid		 = hdr32.resid,
690 			.duration	 = hdr32.duration,
691 			.info		 = hdr32.info,
692 		};
693 
694 		return 0;
695 	}
696 #endif
697 
698 	if (copy_from_user(hdr, argp, sizeof(*hdr)))
699 		return -EFAULT;
700 
701 	return 0;
702 }
703 EXPORT_SYMBOL(get_sg_io_hdr);
704 
705 #ifdef CONFIG_COMPAT
706 struct compat_cdrom_generic_command {
707 	unsigned char	cmd[CDROM_PACKET_SIZE];
708 	compat_caddr_t	buffer;
709 	compat_uint_t	buflen;
710 	compat_int_t	stat;
711 	compat_caddr_t	sense;
712 	unsigned char	data_direction;
713 	unsigned char	pad[3];
714 	compat_int_t	quiet;
715 	compat_int_t	timeout;
716 	compat_caddr_t	unused;
717 };
718 #endif
719 
720 static int scsi_get_cdrom_generic_arg(struct cdrom_generic_command *cgc,
721 				      const void __user *arg)
722 {
723 #ifdef CONFIG_COMPAT
724 	if (in_compat_syscall()) {
725 		struct compat_cdrom_generic_command cgc32;
726 
727 		if (copy_from_user(&cgc32, arg, sizeof(cgc32)))
728 			return -EFAULT;
729 
730 		*cgc = (struct cdrom_generic_command) {
731 			.buffer		= compat_ptr(cgc32.buffer),
732 			.buflen		= cgc32.buflen,
733 			.stat		= cgc32.stat,
734 			.sense		= compat_ptr(cgc32.sense),
735 			.data_direction	= cgc32.data_direction,
736 			.quiet		= cgc32.quiet,
737 			.timeout	= cgc32.timeout,
738 			.unused		= compat_ptr(cgc32.unused),
739 		};
740 		memcpy(&cgc->cmd, &cgc32.cmd, CDROM_PACKET_SIZE);
741 		return 0;
742 	}
743 #endif
744 	if (copy_from_user(cgc, arg, sizeof(*cgc)))
745 		return -EFAULT;
746 
747 	return 0;
748 }
749 
750 static int scsi_put_cdrom_generic_arg(const struct cdrom_generic_command *cgc,
751 				      void __user *arg)
752 {
753 #ifdef CONFIG_COMPAT
754 	if (in_compat_syscall()) {
755 		struct compat_cdrom_generic_command cgc32 = {
756 			.buffer		= (uintptr_t)(cgc->buffer),
757 			.buflen		= cgc->buflen,
758 			.stat		= cgc->stat,
759 			.sense		= (uintptr_t)(cgc->sense),
760 			.data_direction	= cgc->data_direction,
761 			.quiet		= cgc->quiet,
762 			.timeout	= cgc->timeout,
763 			.unused		= (uintptr_t)(cgc->unused),
764 		};
765 		memcpy(&cgc32.cmd, &cgc->cmd, CDROM_PACKET_SIZE);
766 
767 		if (copy_to_user(arg, &cgc32, sizeof(cgc32)))
768 			return -EFAULT;
769 
770 		return 0;
771 	}
772 #endif
773 	if (copy_to_user(arg, cgc, sizeof(*cgc)))
774 		return -EFAULT;
775 
776 	return 0;
777 }
778 
779 static int scsi_cdrom_send_packet(struct scsi_device *sdev, bool open_for_write,
780 		void __user *arg)
781 {
782 	struct cdrom_generic_command cgc;
783 	struct sg_io_hdr hdr;
784 	int err;
785 
786 	err = scsi_get_cdrom_generic_arg(&cgc, arg);
787 	if (err)
788 		return err;
789 
790 	cgc.timeout = clock_t_to_jiffies(cgc.timeout);
791 	memset(&hdr, 0, sizeof(hdr));
792 	hdr.interface_id = 'S';
793 	hdr.cmd_len = sizeof(cgc.cmd);
794 	hdr.dxfer_len = cgc.buflen;
795 	switch (cgc.data_direction) {
796 	case CGC_DATA_UNKNOWN:
797 		hdr.dxfer_direction = SG_DXFER_UNKNOWN;
798 		break;
799 	case CGC_DATA_WRITE:
800 		hdr.dxfer_direction = SG_DXFER_TO_DEV;
801 		break;
802 	case CGC_DATA_READ:
803 		hdr.dxfer_direction = SG_DXFER_FROM_DEV;
804 		break;
805 	case CGC_DATA_NONE:
806 		hdr.dxfer_direction = SG_DXFER_NONE;
807 		break;
808 	default:
809 		return -EINVAL;
810 	}
811 
812 	hdr.dxferp = cgc.buffer;
813 	hdr.sbp = cgc.sense;
814 	if (hdr.sbp)
815 		hdr.mx_sb_len = sizeof(struct request_sense);
816 	hdr.timeout = jiffies_to_msecs(cgc.timeout);
817 	hdr.cmdp = ((struct cdrom_generic_command __user *) arg)->cmd;
818 	hdr.cmd_len = sizeof(cgc.cmd);
819 
820 	err = sg_io(sdev, &hdr, open_for_write);
821 	if (err == -EFAULT)
822 		return -EFAULT;
823 
824 	if (hdr.status)
825 		return -EIO;
826 
827 	cgc.stat = err;
828 	cgc.buflen = hdr.resid;
829 	if (scsi_put_cdrom_generic_arg(&cgc, arg))
830 		return -EFAULT;
831 
832 	return err;
833 }
834 
835 static int scsi_ioctl_sg_io(struct scsi_device *sdev, bool open_for_write,
836 		void __user *argp)
837 {
838 	struct sg_io_hdr hdr;
839 	int error;
840 
841 	error = get_sg_io_hdr(&hdr, argp);
842 	if (error)
843 		return error;
844 	error = sg_io(sdev, &hdr, open_for_write);
845 	if (error == -EFAULT)
846 		return error;
847 	if (put_sg_io_hdr(&hdr, argp))
848 		return -EFAULT;
849 	return error;
850 }
851 
852 /**
853  * scsi_ioctl - Dispatch ioctl to scsi device
854  * @sdev: scsi device receiving ioctl
855  * @open_for_write: is the file / block device opened for writing?
856  * @cmd: which ioctl is it
857  * @arg: data associated with ioctl
858  *
859  * Description: The scsi_ioctl() function differs from most ioctls in that it
860  * does not take a major/minor number as the dev field.  Rather, it takes
861  * a pointer to a &struct scsi_device.
862  */
863 int scsi_ioctl(struct scsi_device *sdev, bool open_for_write, int cmd,
864 		void __user *arg)
865 {
866 	struct request_queue *q = sdev->request_queue;
867 	struct scsi_sense_hdr sense_hdr;
868 
869 	/* Check for deprecated ioctls ... all the ioctls which don't
870 	 * follow the new unique numbering scheme are deprecated */
871 	switch (cmd) {
872 	case SCSI_IOCTL_SEND_COMMAND:
873 	case SCSI_IOCTL_TEST_UNIT_READY:
874 	case SCSI_IOCTL_BENCHMARK_COMMAND:
875 	case SCSI_IOCTL_SYNC:
876 	case SCSI_IOCTL_START_UNIT:
877 	case SCSI_IOCTL_STOP_UNIT:
878 		printk(KERN_WARNING "program %s is using a deprecated SCSI "
879 		       "ioctl, please convert it to SG_IO\n", current->comm);
880 		break;
881 	default:
882 		break;
883 	}
884 
885 	switch (cmd) {
886 	case SG_GET_VERSION_NUM:
887 		return sg_get_version(arg);
888 	case SG_SET_TIMEOUT:
889 		return sg_set_timeout(sdev, arg);
890 	case SG_GET_TIMEOUT:
891 		return jiffies_to_clock_t(sdev->sg_timeout);
892 	case SG_GET_RESERVED_SIZE:
893 		return sg_get_reserved_size(sdev, arg);
894 	case SG_SET_RESERVED_SIZE:
895 		return sg_set_reserved_size(sdev, arg);
896 	case SG_EMULATED_HOST:
897 		return sg_emulated_host(q, arg);
898 	case SG_IO:
899 		return scsi_ioctl_sg_io(sdev, open_for_write, arg);
900 	case SCSI_IOCTL_SEND_COMMAND:
901 		return sg_scsi_ioctl(q, open_for_write, arg);
902 	case CDROM_SEND_PACKET:
903 		return scsi_cdrom_send_packet(sdev, open_for_write, arg);
904 	case CDROMCLOSETRAY:
905 		return scsi_send_start_stop(sdev, 3);
906 	case CDROMEJECT:
907 		return scsi_send_start_stop(sdev, 2);
908 	case SCSI_IOCTL_GET_IDLUN:
909 		return scsi_get_idlun(sdev, arg);
910 	case SCSI_IOCTL_GET_BUS_NUMBER:
911 		return put_user(sdev->host->host_no, (int __user *)arg);
912 	case SCSI_IOCTL_PROBE_HOST:
913 		return ioctl_probe(sdev->host, arg);
914 	case SCSI_IOCTL_DOORLOCK:
915 		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
916 	case SCSI_IOCTL_DOORUNLOCK:
917 		return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
918 	case SCSI_IOCTL_TEST_UNIT_READY:
919 		return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
920 					    NORMAL_RETRIES, &sense_hdr);
921 	case SCSI_IOCTL_START_UNIT:
922 		return scsi_send_start_stop(sdev, 1);
923 	case SCSI_IOCTL_STOP_UNIT:
924 		return scsi_send_start_stop(sdev, 0);
925         case SCSI_IOCTL_GET_PCI:
926                 return scsi_ioctl_get_pci(sdev, arg);
927 	case SG_SCSI_RESET:
928 		return scsi_ioctl_reset(sdev, arg);
929 	}
930 
931 #ifdef CONFIG_COMPAT
932 	if (in_compat_syscall()) {
933 		if (!sdev->host->hostt->compat_ioctl)
934 			return -EINVAL;
935 		return sdev->host->hostt->compat_ioctl(sdev, cmd, arg);
936 	}
937 #endif
938 	if (!sdev->host->hostt->ioctl)
939 		return -EINVAL;
940 	return sdev->host->hostt->ioctl(sdev, cmd, arg);
941 }
942 EXPORT_SYMBOL(scsi_ioctl);
943 
944 /*
945  * We can process a reset even when a device isn't fully operable.
946  */
947 int scsi_ioctl_block_when_processing_errors(struct scsi_device *sdev, int cmd,
948 		bool ndelay)
949 {
950 	if (cmd == SG_SCSI_RESET && ndelay) {
951 		if (scsi_host_in_recovery(sdev->host))
952 			return -EAGAIN;
953 	} else {
954 		if (!scsi_block_when_processing_errors(sdev))
955 			return -ENODEV;
956 	}
957 
958 	return 0;
959 }
960 EXPORT_SYMBOL_GPL(scsi_ioctl_block_when_processing_errors);
961