1/*
2 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 *
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public Licens
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
17 *
18 */
19#include <linux/kernel.h>
20#include <linux/errno.h>
21#include <linux/string.h>
22#include <linux/module.h>
23#include <linux/blkdev.h>
24#include <linux/capability.h>
25#include <linux/completion.h>
26#include <linux/cdrom.h>
27#include <linux/slab.h>
28#include <linux/times.h>
29#include <asm/uaccess.h>
30
31#include <scsi/scsi.h>
32#include <scsi/scsi_ioctl.h>
33#include <scsi/scsi_cmnd.h>
34
35/* Command group 3 is reserved and should never be used.  */
36const unsigned char scsi_command_size[8] =
37{
38	6, 10, 10, 12,
39	16, 12, 10, 10
40};
41
42EXPORT_SYMBOL(scsi_command_size);
43
44#define BLK_DEFAULT_TIMEOUT	(60 * HZ)
45
46#include <scsi/sg.h>
47
48static int sg_get_version(int __user *p)
49{
50	static const int sg_version_num = 30527;
51	return put_user(sg_version_num, p);
52}
53
54static int scsi_get_idlun(request_queue_t *q, int __user *p)
55{
56	return put_user(0, p);
57}
58
59static int scsi_get_bus(request_queue_t *q, int __user *p)
60{
61	return put_user(0, p);
62}
63
64static int sg_get_timeout(request_queue_t *q)
65{
66	return q->sg_timeout / (HZ / USER_HZ);
67}
68
69static int sg_set_timeout(request_queue_t *q, int __user *p)
70{
71	int timeout, err = get_user(timeout, p);
72
73	if (!err)
74		q->sg_timeout = timeout * (HZ / USER_HZ);
75
76	return err;
77}
78
79static int sg_get_reserved_size(request_queue_t *q, int __user *p)
80{
81	unsigned val = min(q->sg_reserved_size, q->max_sectors << 9);
82
83	return put_user(val, p);
84}
85
86static int sg_set_reserved_size(request_queue_t *q, int __user *p)
87{
88	int size, err = get_user(size, p);
89
90	if (err)
91		return err;
92
93	if (size < 0)
94		return -EINVAL;
95	if (size > (q->max_sectors << 9))
96		size = q->max_sectors << 9;
97
98	q->sg_reserved_size = size;
99	return 0;
100}
101
102/*
103 * will always return that we are ATAPI even for a real SCSI drive, I'm not
104 * so sure this is worth doing anything about (why would you care??)
105 */
106static int sg_emulated_host(request_queue_t *q, int __user *p)
107{
108	return put_user(1, p);
109}
110
111#define CMD_READ_SAFE	0x01
112#define CMD_WRITE_SAFE	0x02
113#define CMD_WARNED	0x04
114#define safe_for_read(cmd)	[cmd] = CMD_READ_SAFE
115#define safe_for_write(cmd)	[cmd] = CMD_WRITE_SAFE
116
117static int verify_command(struct file *file, unsigned char *cmd)
118{
119	static unsigned char cmd_type[256] = {
120
121		/* Basic read-only commands */
122		safe_for_read(TEST_UNIT_READY),
123		safe_for_read(REQUEST_SENSE),
124		safe_for_read(READ_6),
125		safe_for_read(READ_10),
126		safe_for_read(READ_12),
127		safe_for_read(READ_16),
128		safe_for_read(READ_BUFFER),
129		safe_for_read(READ_DEFECT_DATA),
130		safe_for_read(READ_LONG),
131		safe_for_read(INQUIRY),
132		safe_for_read(MODE_SENSE),
133		safe_for_read(MODE_SENSE_10),
134		safe_for_read(LOG_SENSE),
135		safe_for_read(START_STOP),
136		safe_for_read(GPCMD_VERIFY_10),
137		safe_for_read(VERIFY_16),
138
139		/* Audio CD commands */
140		safe_for_read(GPCMD_PLAY_CD),
141		safe_for_read(GPCMD_PLAY_AUDIO_10),
142		safe_for_read(GPCMD_PLAY_AUDIO_MSF),
143		safe_for_read(GPCMD_PLAY_AUDIO_TI),
144		safe_for_read(GPCMD_PAUSE_RESUME),
145
146		/* CD/DVD data reading */
147		safe_for_read(GPCMD_READ_BUFFER_CAPACITY),
148		safe_for_read(GPCMD_READ_CD),
149		safe_for_read(GPCMD_READ_CD_MSF),
150		safe_for_read(GPCMD_READ_DISC_INFO),
151		safe_for_read(GPCMD_READ_CDVD_CAPACITY),
152		safe_for_read(GPCMD_READ_DVD_STRUCTURE),
153		safe_for_read(GPCMD_READ_HEADER),
154		safe_for_read(GPCMD_READ_TRACK_RZONE_INFO),
155		safe_for_read(GPCMD_READ_SUBCHANNEL),
156		safe_for_read(GPCMD_READ_TOC_PMA_ATIP),
157		safe_for_read(GPCMD_REPORT_KEY),
158		safe_for_read(GPCMD_SCAN),
159		safe_for_read(GPCMD_GET_CONFIGURATION),
160		safe_for_read(GPCMD_READ_FORMAT_CAPACITIES),
161		safe_for_read(GPCMD_GET_EVENT_STATUS_NOTIFICATION),
162		safe_for_read(GPCMD_GET_PERFORMANCE),
163		safe_for_read(GPCMD_SEEK),
164		safe_for_read(GPCMD_STOP_PLAY_SCAN),
165
166		/* Basic writing commands */
167		safe_for_write(WRITE_6),
168		safe_for_write(WRITE_10),
169		safe_for_write(WRITE_VERIFY),
170		safe_for_write(WRITE_12),
171		safe_for_write(WRITE_VERIFY_12),
172		safe_for_write(WRITE_16),
173		safe_for_write(WRITE_LONG),
174		safe_for_write(WRITE_LONG_2),
175		safe_for_write(ERASE),
176		safe_for_write(GPCMD_MODE_SELECT_10),
177		safe_for_write(MODE_SELECT),
178		safe_for_write(LOG_SELECT),
179		safe_for_write(GPCMD_BLANK),
180		safe_for_write(GPCMD_CLOSE_TRACK),
181		safe_for_write(GPCMD_FLUSH_CACHE),
182		safe_for_write(GPCMD_FORMAT_UNIT),
183		safe_for_write(GPCMD_REPAIR_RZONE_TRACK),
184		safe_for_write(GPCMD_RESERVE_RZONE_TRACK),
185		safe_for_write(GPCMD_SEND_DVD_STRUCTURE),
186		safe_for_write(GPCMD_SEND_EVENT),
187		safe_for_write(GPCMD_SEND_KEY),
188		safe_for_write(GPCMD_SEND_OPC),
189		safe_for_write(GPCMD_SEND_CUE_SHEET),
190		safe_for_write(GPCMD_SET_SPEED),
191		safe_for_write(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL),
192		safe_for_write(GPCMD_LOAD_UNLOAD),
193		safe_for_write(GPCMD_SET_STREAMING),
194	};
195	unsigned char type = cmd_type[cmd[0]];
196	int has_write_perm = 0;
197
198	/* Anybody who can open the device can do a read-safe command */
199	if (type & CMD_READ_SAFE)
200		return 0;
201
202	/*
203	 * file can be NULL from ioctl_by_bdev()...
204	 */
205	if (file)
206		has_write_perm = file->f_mode & FMODE_WRITE;
207
208	/* Write-safe commands just require a writable open.. */
209	if ((type & CMD_WRITE_SAFE) && has_write_perm)
210		return 0;
211
212	/* And root can do any command.. */
213	if (capable(CAP_SYS_RAWIO))
214		return 0;
215
216	if (!type) {
217		cmd_type[cmd[0]] = CMD_WARNED;
218		printk(KERN_WARNING "scsi: unknown opcode 0x%02x\n", cmd[0]);
219	}
220
221	/* Otherwise fail it with an "Operation not permitted" */
222	return -EPERM;
223}
224
225static int sg_io(struct file *file, request_queue_t *q,
226		struct gendisk *bd_disk, struct sg_io_hdr *hdr)
227{
228	unsigned long start_time, timeout;
229	int writing = 0, ret = 0;
230	struct request *rq;
231	char sense[SCSI_SENSE_BUFFERSIZE];
232	unsigned char cmd[BLK_MAX_CDB];
233	struct bio *bio;
234
235	if (hdr->interface_id != 'S')
236		return -EINVAL;
237	if (hdr->cmd_len > BLK_MAX_CDB)
238		return -EINVAL;
239	if (copy_from_user(cmd, hdr->cmdp, hdr->cmd_len))
240		return -EFAULT;
241	if (verify_command(file, cmd))
242		return -EPERM;
243
244	if (hdr->dxfer_len > (q->max_hw_sectors << 9))
245		return -EIO;
246
247	if (hdr->dxfer_len)
248		switch (hdr->dxfer_direction) {
249		default:
250			return -EINVAL;
251		case SG_DXFER_TO_DEV:
252			writing = 1;
253			break;
254		case SG_DXFER_TO_FROM_DEV:
255		case SG_DXFER_FROM_DEV:
256			break;
257		}
258
259	rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
260	if (!rq)
261		return -ENOMEM;
262
263	/*
264	 * fill in request structure
265	 */
266	rq->cmd_len = hdr->cmd_len;
267	memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
268	memcpy(rq->cmd, cmd, hdr->cmd_len);
269
270	memset(sense, 0, sizeof(sense));
271	rq->sense = sense;
272	rq->sense_len = 0;
273
274	rq->cmd_type = REQ_TYPE_BLOCK_PC;
275
276	timeout = msecs_to_jiffies(hdr->timeout);
277	rq->timeout = (timeout < INT_MAX) ? timeout : INT_MAX;
278	if (!rq->timeout)
279		rq->timeout = q->sg_timeout;
280	if (!rq->timeout)
281		rq->timeout = BLK_DEFAULT_TIMEOUT;
282
283	if (hdr->iovec_count) {
284		const int size = sizeof(struct sg_iovec) * hdr->iovec_count;
285		struct sg_iovec *iov;
286
287		iov = kmalloc(size, GFP_KERNEL);
288		if (!iov) {
289			ret = -ENOMEM;
290			goto out;
291		}
292
293		if (copy_from_user(iov, hdr->dxferp, size)) {
294			kfree(iov);
295			ret = -EFAULT;
296			goto out;
297		}
298
299		ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count,
300					  hdr->dxfer_len);
301		kfree(iov);
302	} else if (hdr->dxfer_len)
303		ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len);
304
305	if (ret)
306		goto out;
307
308	bio = rq->bio;
309	rq->retries = 0;
310
311	start_time = jiffies;
312
313	/* ignore return value. All information is passed back to caller
314	 * (if he doesn't check that is his problem).
315	 * N.B. a non-zero SCSI status is _not_ necessarily an error.
316	 */
317	blk_execute_rq(q, bd_disk, rq, 0);
318
319	/* write to all output members */
320	hdr->status = 0xff & rq->errors;
321	hdr->masked_status = status_byte(rq->errors);
322	hdr->msg_status = msg_byte(rq->errors);
323	hdr->host_status = host_byte(rq->errors);
324	hdr->driver_status = driver_byte(rq->errors);
325	hdr->info = 0;
326	if (hdr->masked_status || hdr->host_status || hdr->driver_status)
327		hdr->info |= SG_INFO_CHECK;
328	hdr->resid = rq->data_len;
329	hdr->duration = ((jiffies - start_time) * 1000) / HZ;
330	hdr->sb_len_wr = 0;
331
332	if (rq->sense_len && hdr->sbp) {
333		int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
334
335		if (!copy_to_user(hdr->sbp, rq->sense, len))
336			hdr->sb_len_wr = len;
337	}
338
339	if (blk_rq_unmap_user(bio))
340		ret = -EFAULT;
341
342	/* may not have succeeded, but output values written to control
343	 * structure (struct sg_io_hdr).  */
344out:
345	blk_put_request(rq);
346	return ret;
347}
348
349/**
350 * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
351 * @file:	file this ioctl operates on (optional)
352 * @q:		request queue to send scsi commands down
353 * @disk:	gendisk to operate on (option)
354 * @sic:	userspace structure describing the command to perform
355 *
356 * Send down the scsi command described by @sic to the device below
357 * the request queue @q.  If @file is non-NULL it's used to perform
358 * fine-grained permission checks that allow users to send down
359 * non-destructive SCSI commands.  If the caller has a struct gendisk
360 * available it should be passed in as @disk to allow the low level
361 * driver to use the information contained in it.  A non-NULL @disk
362 * is only allowed if the caller knows that the low level driver doesn't
363 * need it (e.g. in the scsi subsystem).
364 *
365 * Notes:
366 *   -  This interface is deprecated - users should use the SG_IO
367 *      interface instead, as this is a more flexible approach to
368 *      performing SCSI commands on a device.
369 *   -  The SCSI command length is determined by examining the 1st byte
370 *      of the given command. There is no way to override this.
371 *   -  Data transfers are limited to PAGE_SIZE
372 *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
373 *      accommodate the sense buffer when an error occurs.
374 *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
375 *      old code will not be surprised.
376 *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
377 *      a negative return and the Unix error code in 'errno'.
378 *      If the SCSI command succeeds then 0 is returned.
379 *      Positive numbers returned are the compacted SCSI error codes (4
380 *      bytes in one int) where the lowest byte is the SCSI status.
381 */
382#define OMAX_SB_LEN 16          /* For backward compatibility */
383int sg_scsi_ioctl(struct file *file, struct request_queue *q,
384		  struct gendisk *disk, struct scsi_ioctl_command __user *sic)
385{
386	struct request *rq;
387	int err;
388	unsigned int in_len, out_len, bytes, opcode, cmdlen;
389	char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
390
391	if (!sic)
392		return -EINVAL;
393
394	/*
395	 * get in an out lengths, verify they don't exceed a page worth of data
396	 */
397	if (get_user(in_len, &sic->inlen))
398		return -EFAULT;
399	if (get_user(out_len, &sic->outlen))
400		return -EFAULT;
401	if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
402		return -EINVAL;
403	if (get_user(opcode, sic->data))
404		return -EFAULT;
405
406	bytes = max(in_len, out_len);
407	if (bytes) {
408		buffer = kmalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
409		if (!buffer)
410			return -ENOMEM;
411
412		memset(buffer, 0, bytes);
413	}
414
415	rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
416
417	cmdlen = COMMAND_SIZE(opcode);
418
419	/*
420	 * get command and data to send to device, if any
421	 */
422	err = -EFAULT;
423	rq->cmd_len = cmdlen;
424	if (copy_from_user(rq->cmd, sic->data, cmdlen))
425		goto error;
426
427	if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
428		goto error;
429
430	err = verify_command(file, rq->cmd);
431	if (err)
432		goto error;
433
434	/* default.  possible overriden later */
435	rq->retries = 5;
436
437	switch (opcode) {
438	case SEND_DIAGNOSTIC:
439	case FORMAT_UNIT:
440		rq->timeout = FORMAT_UNIT_TIMEOUT;
441		rq->retries = 1;
442		break;
443	case START_STOP:
444		rq->timeout = START_STOP_TIMEOUT;
445		break;
446	case MOVE_MEDIUM:
447		rq->timeout = MOVE_MEDIUM_TIMEOUT;
448		break;
449	case READ_ELEMENT_STATUS:
450		rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
451		break;
452	case READ_DEFECT_DATA:
453		rq->timeout = READ_DEFECT_DATA_TIMEOUT;
454		rq->retries = 1;
455		break;
456	default:
457		rq->timeout = BLK_DEFAULT_TIMEOUT;
458		break;
459	}
460
461	if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
462		err = DRIVER_ERROR << 24;
463		goto out;
464	}
465
466	memset(sense, 0, sizeof(sense));
467	rq->sense = sense;
468	rq->sense_len = 0;
469	rq->cmd_type = REQ_TYPE_BLOCK_PC;
470
471	blk_execute_rq(q, disk, rq, 0);
472
473out:
474	err = rq->errors & 0xff;	/* only 8 bit SCSI status */
475	if (err) {
476		if (rq->sense_len && rq->sense) {
477			bytes = (OMAX_SB_LEN > rq->sense_len) ?
478				rq->sense_len : OMAX_SB_LEN;
479			if (copy_to_user(sic->data, rq->sense, bytes))
480				err = -EFAULT;
481		}
482	} else {
483		if (copy_to_user(sic->data, buffer, out_len))
484			err = -EFAULT;
485	}
486
487error:
488	kfree(buffer);
489	blk_put_request(rq);
490	return err;
491}
492EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
493
494/* Send basic block requests */
495static int __blk_send_generic(request_queue_t *q, struct gendisk *bd_disk, int cmd, int data)
496{
497	struct request *rq;
498	int err;
499
500	rq = blk_get_request(q, WRITE, __GFP_WAIT);
501	rq->cmd_type = REQ_TYPE_BLOCK_PC;
502	rq->data = NULL;
503	rq->data_len = 0;
504	rq->timeout = BLK_DEFAULT_TIMEOUT;
505	memset(rq->cmd, 0, sizeof(rq->cmd));
506	rq->cmd[0] = cmd;
507	rq->cmd[4] = data;
508	rq->cmd_len = 6;
509	err = blk_execute_rq(q, bd_disk, rq, 0);
510	blk_put_request(rq);
511
512	return err;
513}
514
515static inline int blk_send_start_stop(request_queue_t *q, struct gendisk *bd_disk, int data)
516{
517	return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
518}
519
520int scsi_cmd_ioctl(struct file *file, struct gendisk *bd_disk, unsigned int cmd, void __user *arg)
521{
522	request_queue_t *q;
523	int err;
524
525	q = bd_disk->queue;
526	if (!q)
527		return -ENXIO;
528
529	if (blk_get_queue(q))
530		return -ENXIO;
531
532	switch (cmd) {
533		/*
534		 * new sgv3 interface
535		 */
536		case SG_GET_VERSION_NUM:
537			err = sg_get_version(arg);
538			break;
539		case SCSI_IOCTL_GET_IDLUN:
540			err = scsi_get_idlun(q, arg);
541			break;
542		case SCSI_IOCTL_GET_BUS_NUMBER:
543			err = scsi_get_bus(q, arg);
544			break;
545		case SG_SET_TIMEOUT:
546			err = sg_set_timeout(q, arg);
547			break;
548		case SG_GET_TIMEOUT:
549			err = sg_get_timeout(q);
550			break;
551		case SG_GET_RESERVED_SIZE:
552			err = sg_get_reserved_size(q, arg);
553			break;
554		case SG_SET_RESERVED_SIZE:
555			err = sg_set_reserved_size(q, arg);
556			break;
557		case SG_EMULATED_HOST:
558			err = sg_emulated_host(q, arg);
559			break;
560		case SG_IO: {
561			struct sg_io_hdr hdr;
562
563			err = -EFAULT;
564			if (copy_from_user(&hdr, arg, sizeof(hdr)))
565				break;
566			err = sg_io(file, q, bd_disk, &hdr);
567			if (err == -EFAULT)
568				break;
569
570			if (copy_to_user(arg, &hdr, sizeof(hdr)))
571				err = -EFAULT;
572			break;
573		}
574		case CDROM_SEND_PACKET: {
575			struct cdrom_generic_command cgc;
576			struct sg_io_hdr hdr;
577
578			err = -EFAULT;
579			if (copy_from_user(&cgc, arg, sizeof(cgc)))
580				break;
581			cgc.timeout = clock_t_to_jiffies(cgc.timeout);
582			memset(&hdr, 0, sizeof(hdr));
583			hdr.interface_id = 'S';
584			hdr.cmd_len = sizeof(cgc.cmd);
585			hdr.dxfer_len = cgc.buflen;
586			err = 0;
587			switch (cgc.data_direction) {
588				case CGC_DATA_UNKNOWN:
589					hdr.dxfer_direction = SG_DXFER_UNKNOWN;
590					break;
591				case CGC_DATA_WRITE:
592					hdr.dxfer_direction = SG_DXFER_TO_DEV;
593					break;
594				case CGC_DATA_READ:
595					hdr.dxfer_direction = SG_DXFER_FROM_DEV;
596					break;
597				case CGC_DATA_NONE:
598					hdr.dxfer_direction = SG_DXFER_NONE;
599					break;
600				default:
601					err = -EINVAL;
602			}
603			if (err)
604				break;
605
606			hdr.dxferp = cgc.buffer;
607			hdr.sbp = cgc.sense;
608			if (hdr.sbp)
609				hdr.mx_sb_len = sizeof(struct request_sense);
610			hdr.timeout = cgc.timeout;
611			hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
612			hdr.cmd_len = sizeof(cgc.cmd);
613
614			err = sg_io(file, q, bd_disk, &hdr);
615			if (err == -EFAULT)
616				break;
617
618			if (hdr.status)
619				err = -EIO;
620
621			cgc.stat = err;
622			cgc.buflen = hdr.resid;
623			if (copy_to_user(arg, &cgc, sizeof(cgc)))
624				err = -EFAULT;
625
626			break;
627		}
628
629		/*
630		 * old junk scsi send command ioctl
631		 */
632		case SCSI_IOCTL_SEND_COMMAND:
633			printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
634			err = -EINVAL;
635			if (!arg)
636				break;
637
638			err = sg_scsi_ioctl(file, q, bd_disk, arg);
639			break;
640		case CDROMCLOSETRAY:
641			err = blk_send_start_stop(q, bd_disk, 0x03);
642			break;
643		case CDROMEJECT:
644			err = blk_send_start_stop(q, bd_disk, 0x02);
645			break;
646		default:
647			err = -ENOTTY;
648	}
649
650	blk_put_queue(q);
651	return err;
652}
653
654EXPORT_SYMBOL(scsi_cmd_ioctl);
655