Merge tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl...
[sfrench/cifs-2.6.git] / block / scsi_ioctl.c
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/ratelimit.h>
28 #include <linux/slab.h>
29 #include <linux/times.h>
30 #include <linux/uio.h>
31 #include <asm/uaccess.h>
32
33 #include <scsi/scsi.h>
34 #include <scsi/scsi_ioctl.h>
35 #include <scsi/scsi_cmnd.h>
36
37 struct blk_cmd_filter {
38         unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
39         unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
40 };
41
42 static struct blk_cmd_filter blk_default_cmd_filter;
43
44 /* Command group 3 is reserved and should never be used.  */
45 const unsigned char scsi_command_size_tbl[8] =
46 {
47         6, 10, 10, 12,
48         16, 12, 10, 10
49 };
50 EXPORT_SYMBOL(scsi_command_size_tbl);
51
52 #include <scsi/sg.h>
53
54 static int sg_get_version(int __user *p)
55 {
56         static const int sg_version_num = 30527;
57         return put_user(sg_version_num, p);
58 }
59
60 static int scsi_get_idlun(struct request_queue *q, int __user *p)
61 {
62         return put_user(0, p);
63 }
64
65 static int scsi_get_bus(struct request_queue *q, int __user *p)
66 {
67         return put_user(0, p);
68 }
69
70 static int sg_get_timeout(struct request_queue *q)
71 {
72         return jiffies_to_clock_t(q->sg_timeout);
73 }
74
75 static int sg_set_timeout(struct request_queue *q, int __user *p)
76 {
77         int timeout, err = get_user(timeout, p);
78
79         if (!err)
80                 q->sg_timeout = clock_t_to_jiffies(timeout);
81
82         return err;
83 }
84
85 static int max_sectors_bytes(struct request_queue *q)
86 {
87         unsigned int max_sectors = queue_max_sectors(q);
88
89         max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
90
91         return max_sectors << 9;
92 }
93
94 static int sg_get_reserved_size(struct request_queue *q, int __user *p)
95 {
96         int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q));
97
98         return put_user(val, p);
99 }
100
101 static int sg_set_reserved_size(struct request_queue *q, int __user *p)
102 {
103         int size, err = get_user(size, p);
104
105         if (err)
106                 return err;
107
108         if (size < 0)
109                 return -EINVAL;
110
111         q->sg_reserved_size = min(size, max_sectors_bytes(q));
112         return 0;
113 }
114
115 /*
116  * will always return that we are ATAPI even for a real SCSI drive, I'm not
117  * so sure this is worth doing anything about (why would you care??)
118  */
119 static int sg_emulated_host(struct request_queue *q, int __user *p)
120 {
121         return put_user(1, p);
122 }
123
124 static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
125 {
126         /* Basic read-only commands */
127         __set_bit(TEST_UNIT_READY, filter->read_ok);
128         __set_bit(REQUEST_SENSE, filter->read_ok);
129         __set_bit(READ_6, filter->read_ok);
130         __set_bit(READ_10, filter->read_ok);
131         __set_bit(READ_12, filter->read_ok);
132         __set_bit(READ_16, filter->read_ok);
133         __set_bit(READ_BUFFER, filter->read_ok);
134         __set_bit(READ_DEFECT_DATA, filter->read_ok);
135         __set_bit(READ_CAPACITY, filter->read_ok);
136         __set_bit(READ_LONG, filter->read_ok);
137         __set_bit(INQUIRY, filter->read_ok);
138         __set_bit(MODE_SENSE, filter->read_ok);
139         __set_bit(MODE_SENSE_10, filter->read_ok);
140         __set_bit(LOG_SENSE, filter->read_ok);
141         __set_bit(START_STOP, filter->read_ok);
142         __set_bit(GPCMD_VERIFY_10, filter->read_ok);
143         __set_bit(VERIFY_16, filter->read_ok);
144         __set_bit(REPORT_LUNS, filter->read_ok);
145         __set_bit(SERVICE_ACTION_IN_16, filter->read_ok);
146         __set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
147         __set_bit(MAINTENANCE_IN, filter->read_ok);
148         __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
149
150         /* Audio CD commands */
151         __set_bit(GPCMD_PLAY_CD, filter->read_ok);
152         __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
153         __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
154         __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
155         __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
156
157         /* CD/DVD data reading */
158         __set_bit(GPCMD_READ_CD, filter->read_ok);
159         __set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
160         __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
161         __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
162         __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
163         __set_bit(GPCMD_READ_HEADER, filter->read_ok);
164         __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
165         __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
166         __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
167         __set_bit(GPCMD_REPORT_KEY, filter->read_ok);
168         __set_bit(GPCMD_SCAN, filter->read_ok);
169         __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
170         __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
171         __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
172         __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
173         __set_bit(GPCMD_SEEK, filter->read_ok);
174         __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
175
176         /* Basic writing commands */
177         __set_bit(WRITE_6, filter->write_ok);
178         __set_bit(WRITE_10, filter->write_ok);
179         __set_bit(WRITE_VERIFY, filter->write_ok);
180         __set_bit(WRITE_12, filter->write_ok);
181         __set_bit(WRITE_VERIFY_12, filter->write_ok);
182         __set_bit(WRITE_16, filter->write_ok);
183         __set_bit(WRITE_LONG, filter->write_ok);
184         __set_bit(WRITE_LONG_2, filter->write_ok);
185         __set_bit(ERASE, filter->write_ok);
186         __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
187         __set_bit(MODE_SELECT, filter->write_ok);
188         __set_bit(LOG_SELECT, filter->write_ok);
189         __set_bit(GPCMD_BLANK, filter->write_ok);
190         __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
191         __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
192         __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
193         __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
194         __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
195         __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
196         __set_bit(GPCMD_SEND_EVENT, filter->write_ok);
197         __set_bit(GPCMD_SEND_KEY, filter->write_ok);
198         __set_bit(GPCMD_SEND_OPC, filter->write_ok);
199         __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
200         __set_bit(GPCMD_SET_SPEED, filter->write_ok);
201         __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
202         __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
203         __set_bit(GPCMD_SET_STREAMING, filter->write_ok);
204         __set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
205 }
206
207 int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
208 {
209         struct blk_cmd_filter *filter = &blk_default_cmd_filter;
210
211         /* root can do any command. */
212         if (capable(CAP_SYS_RAWIO))
213                 return 0;
214
215         /* Anybody who can open the device can do a read-safe command */
216         if (test_bit(cmd[0], filter->read_ok))
217                 return 0;
218
219         /* Write-safe commands require a writable open */
220         if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
221                 return 0;
222
223         return -EPERM;
224 }
225 EXPORT_SYMBOL(blk_verify_command);
226
227 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
228                              struct sg_io_hdr *hdr, fmode_t mode)
229 {
230         if (copy_from_user(rq->cmd, hdr->cmdp, hdr->cmd_len))
231                 return -EFAULT;
232         if (blk_verify_command(rq->cmd, mode & FMODE_WRITE))
233                 return -EPERM;
234
235         /*
236          * fill in request structure
237          */
238         rq->cmd_len = hdr->cmd_len;
239
240         rq->timeout = msecs_to_jiffies(hdr->timeout);
241         if (!rq->timeout)
242                 rq->timeout = q->sg_timeout;
243         if (!rq->timeout)
244                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
245         if (rq->timeout < BLK_MIN_SG_TIMEOUT)
246                 rq->timeout = BLK_MIN_SG_TIMEOUT;
247
248         return 0;
249 }
250
251 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
252                                  struct bio *bio)
253 {
254         int r, ret = 0;
255
256         /*
257          * fill in all the output members
258          */
259         hdr->status = rq->errors & 0xff;
260         hdr->masked_status = status_byte(rq->errors);
261         hdr->msg_status = msg_byte(rq->errors);
262         hdr->host_status = host_byte(rq->errors);
263         hdr->driver_status = driver_byte(rq->errors);
264         hdr->info = 0;
265         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
266                 hdr->info |= SG_INFO_CHECK;
267         hdr->resid = rq->resid_len;
268         hdr->sb_len_wr = 0;
269
270         if (rq->sense_len && hdr->sbp) {
271                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
272
273                 if (!copy_to_user(hdr->sbp, rq->sense, len))
274                         hdr->sb_len_wr = len;
275                 else
276                         ret = -EFAULT;
277         }
278
279         r = blk_rq_unmap_user(bio);
280         if (!ret)
281                 ret = r;
282
283         return ret;
284 }
285
286 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
287                 struct sg_io_hdr *hdr, fmode_t mode)
288 {
289         unsigned long start_time;
290         ssize_t ret = 0;
291         int writing = 0;
292         int at_head = 0;
293         struct request *rq;
294         char sense[SCSI_SENSE_BUFFERSIZE];
295         struct bio *bio;
296
297         if (hdr->interface_id != 'S')
298                 return -EINVAL;
299
300         if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
301                 return -EIO;
302
303         if (hdr->dxfer_len)
304                 switch (hdr->dxfer_direction) {
305                 default:
306                         return -EINVAL;
307                 case SG_DXFER_TO_DEV:
308                         writing = 1;
309                         break;
310                 case SG_DXFER_TO_FROM_DEV:
311                 case SG_DXFER_FROM_DEV:
312                         break;
313                 }
314         if (hdr->flags & SG_FLAG_Q_AT_HEAD)
315                 at_head = 1;
316
317         ret = -ENOMEM;
318         rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
319         if (IS_ERR(rq))
320                 return PTR_ERR(rq);
321         blk_rq_set_block_pc(rq);
322
323         if (hdr->cmd_len > BLK_MAX_CDB) {
324                 rq->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
325                 if (!rq->cmd)
326                         goto out_put_request;
327         }
328
329         ret = -EFAULT;
330         if (blk_fill_sghdr_rq(q, rq, hdr, mode))
331                 goto out_free_cdb;
332
333         ret = 0;
334         if (hdr->iovec_count) {
335                 struct iov_iter i;
336                 struct iovec *iov = NULL;
337
338                 ret = import_iovec(rq_data_dir(rq),
339                                    hdr->dxferp, hdr->iovec_count,
340                                    0, &iov, &i);
341                 if (ret < 0)
342                         goto out_free_cdb;
343
344                 /* SG_IO howto says that the shorter of the two wins */
345                 iov_iter_truncate(&i, hdr->dxfer_len);
346
347                 ret = blk_rq_map_user_iov(q, rq, NULL, &i, GFP_KERNEL);
348                 kfree(iov);
349         } else if (hdr->dxfer_len)
350                 ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
351                                       GFP_KERNEL);
352
353         if (ret)
354                 goto out_free_cdb;
355
356         bio = rq->bio;
357         memset(sense, 0, sizeof(sense));
358         rq->sense = sense;
359         rq->sense_len = 0;
360         rq->retries = 0;
361
362         start_time = jiffies;
363
364         /* ignore return value. All information is passed back to caller
365          * (if he doesn't check that is his problem).
366          * N.B. a non-zero SCSI status is _not_ necessarily an error.
367          */
368         blk_execute_rq(q, bd_disk, rq, at_head);
369
370         hdr->duration = jiffies_to_msecs(jiffies - start_time);
371
372         ret = blk_complete_sghdr_rq(rq, hdr, bio);
373
374 out_free_cdb:
375         if (rq->cmd != rq->__cmd)
376                 kfree(rq->cmd);
377 out_put_request:
378         blk_put_request(rq);
379         return ret;
380 }
381
382 /**
383  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
384  * @file:       file this ioctl operates on (optional)
385  * @q:          request queue to send scsi commands down
386  * @disk:       gendisk to operate on (option)
387  * @sic:        userspace structure describing the command to perform
388  *
389  * Send down the scsi command described by @sic to the device below
390  * the request queue @q.  If @file is non-NULL it's used to perform
391  * fine-grained permission checks that allow users to send down
392  * non-destructive SCSI commands.  If the caller has a struct gendisk
393  * available it should be passed in as @disk to allow the low level
394  * driver to use the information contained in it.  A non-NULL @disk
395  * is only allowed if the caller knows that the low level driver doesn't
396  * need it (e.g. in the scsi subsystem).
397  *
398  * Notes:
399  *   -  This interface is deprecated - users should use the SG_IO
400  *      interface instead, as this is a more flexible approach to
401  *      performing SCSI commands on a device.
402  *   -  The SCSI command length is determined by examining the 1st byte
403  *      of the given command. There is no way to override this.
404  *   -  Data transfers are limited to PAGE_SIZE
405  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
406  *      accommodate the sense buffer when an error occurs.
407  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
408  *      old code will not be surprised.
409  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
410  *      a negative return and the Unix error code in 'errno'.
411  *      If the SCSI command succeeds then 0 is returned.
412  *      Positive numbers returned are the compacted SCSI error codes (4
413  *      bytes in one int) where the lowest byte is the SCSI status.
414  */
415 #define OMAX_SB_LEN 16          /* For backward compatibility */
416 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
417                 struct scsi_ioctl_command __user *sic)
418 {
419         struct request *rq;
420         int err;
421         unsigned int in_len, out_len, bytes, opcode, cmdlen;
422         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
423
424         if (!sic)
425                 return -EINVAL;
426
427         /*
428          * get in an out lengths, verify they don't exceed a page worth of data
429          */
430         if (get_user(in_len, &sic->inlen))
431                 return -EFAULT;
432         if (get_user(out_len, &sic->outlen))
433                 return -EFAULT;
434         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
435                 return -EINVAL;
436         if (get_user(opcode, sic->data))
437                 return -EFAULT;
438
439         bytes = max(in_len, out_len);
440         if (bytes) {
441                 buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
442                 if (!buffer)
443                         return -ENOMEM;
444
445         }
446
447         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
448         if (IS_ERR(rq)) {
449                 err = PTR_ERR(rq);
450                 goto error_free_buffer;
451         }
452         blk_rq_set_block_pc(rq);
453
454         cmdlen = COMMAND_SIZE(opcode);
455
456         /*
457          * get command and data to send to device, if any
458          */
459         err = -EFAULT;
460         rq->cmd_len = cmdlen;
461         if (copy_from_user(rq->cmd, sic->data, cmdlen))
462                 goto error;
463
464         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
465                 goto error;
466
467         err = blk_verify_command(rq->cmd, mode & FMODE_WRITE);
468         if (err)
469                 goto error;
470
471         /* default.  possible overriden later */
472         rq->retries = 5;
473
474         switch (opcode) {
475         case SEND_DIAGNOSTIC:
476         case FORMAT_UNIT:
477                 rq->timeout = FORMAT_UNIT_TIMEOUT;
478                 rq->retries = 1;
479                 break;
480         case START_STOP:
481                 rq->timeout = START_STOP_TIMEOUT;
482                 break;
483         case MOVE_MEDIUM:
484                 rq->timeout = MOVE_MEDIUM_TIMEOUT;
485                 break;
486         case READ_ELEMENT_STATUS:
487                 rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
488                 break;
489         case READ_DEFECT_DATA:
490                 rq->timeout = READ_DEFECT_DATA_TIMEOUT;
491                 rq->retries = 1;
492                 break;
493         default:
494                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
495                 break;
496         }
497
498         if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
499                 err = DRIVER_ERROR << 24;
500                 goto error;
501         }
502
503         memset(sense, 0, sizeof(sense));
504         rq->sense = sense;
505         rq->sense_len = 0;
506
507         blk_execute_rq(q, disk, rq, 0);
508
509         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
510         if (err) {
511                 if (rq->sense_len && rq->sense) {
512                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
513                                 rq->sense_len : OMAX_SB_LEN;
514                         if (copy_to_user(sic->data, rq->sense, bytes))
515                                 err = -EFAULT;
516                 }
517         } else {
518                 if (copy_to_user(sic->data, buffer, out_len))
519                         err = -EFAULT;
520         }
521         
522 error:
523         blk_put_request(rq);
524
525 error_free_buffer:
526         kfree(buffer);
527
528         return err;
529 }
530 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
531
532 /* Send basic block requests */
533 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
534                               int cmd, int data)
535 {
536         struct request *rq;
537         int err;
538
539         rq = blk_get_request(q, WRITE, __GFP_WAIT);
540         if (IS_ERR(rq))
541                 return PTR_ERR(rq);
542         blk_rq_set_block_pc(rq);
543         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
544         rq->cmd[0] = cmd;
545         rq->cmd[4] = data;
546         rq->cmd_len = 6;
547         err = blk_execute_rq(q, bd_disk, rq, 0);
548         blk_put_request(rq);
549
550         return err;
551 }
552
553 static inline int blk_send_start_stop(struct request_queue *q,
554                                       struct gendisk *bd_disk, int data)
555 {
556         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
557 }
558
559 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
560                    unsigned int cmd, void __user *arg)
561 {
562         int err;
563
564         if (!q)
565                 return -ENXIO;
566
567         switch (cmd) {
568                 /*
569                  * new sgv3 interface
570                  */
571                 case SG_GET_VERSION_NUM:
572                         err = sg_get_version(arg);
573                         break;
574                 case SCSI_IOCTL_GET_IDLUN:
575                         err = scsi_get_idlun(q, arg);
576                         break;
577                 case SCSI_IOCTL_GET_BUS_NUMBER:
578                         err = scsi_get_bus(q, arg);
579                         break;
580                 case SG_SET_TIMEOUT:
581                         err = sg_set_timeout(q, arg);
582                         break;
583                 case SG_GET_TIMEOUT:
584                         err = sg_get_timeout(q);
585                         break;
586                 case SG_GET_RESERVED_SIZE:
587                         err = sg_get_reserved_size(q, arg);
588                         break;
589                 case SG_SET_RESERVED_SIZE:
590                         err = sg_set_reserved_size(q, arg);
591                         break;
592                 case SG_EMULATED_HOST:
593                         err = sg_emulated_host(q, arg);
594                         break;
595                 case SG_IO: {
596                         struct sg_io_hdr hdr;
597
598                         err = -EFAULT;
599                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
600                                 break;
601                         err = sg_io(q, bd_disk, &hdr, mode);
602                         if (err == -EFAULT)
603                                 break;
604
605                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
606                                 err = -EFAULT;
607                         break;
608                 }
609                 case CDROM_SEND_PACKET: {
610                         struct cdrom_generic_command cgc;
611                         struct sg_io_hdr hdr;
612
613                         err = -EFAULT;
614                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
615                                 break;
616                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
617                         memset(&hdr, 0, sizeof(hdr));
618                         hdr.interface_id = 'S';
619                         hdr.cmd_len = sizeof(cgc.cmd);
620                         hdr.dxfer_len = cgc.buflen;
621                         err = 0;
622                         switch (cgc.data_direction) {
623                                 case CGC_DATA_UNKNOWN:
624                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
625                                         break;
626                                 case CGC_DATA_WRITE:
627                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
628                                         break;
629                                 case CGC_DATA_READ:
630                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
631                                         break;
632                                 case CGC_DATA_NONE:
633                                         hdr.dxfer_direction = SG_DXFER_NONE;
634                                         break;
635                                 default:
636                                         err = -EINVAL;
637                         }
638                         if (err)
639                                 break;
640
641                         hdr.dxferp = cgc.buffer;
642                         hdr.sbp = cgc.sense;
643                         if (hdr.sbp)
644                                 hdr.mx_sb_len = sizeof(struct request_sense);
645                         hdr.timeout = jiffies_to_msecs(cgc.timeout);
646                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
647                         hdr.cmd_len = sizeof(cgc.cmd);
648
649                         err = sg_io(q, bd_disk, &hdr, mode);
650                         if (err == -EFAULT)
651                                 break;
652
653                         if (hdr.status)
654                                 err = -EIO;
655
656                         cgc.stat = err;
657                         cgc.buflen = hdr.resid;
658                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
659                                 err = -EFAULT;
660
661                         break;
662                 }
663
664                 /*
665                  * old junk scsi send command ioctl
666                  */
667                 case SCSI_IOCTL_SEND_COMMAND:
668                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
669                         err = -EINVAL;
670                         if (!arg)
671                                 break;
672
673                         err = sg_scsi_ioctl(q, bd_disk, mode, arg);
674                         break;
675                 case CDROMCLOSETRAY:
676                         err = blk_send_start_stop(q, bd_disk, 0x03);
677                         break;
678                 case CDROMEJECT:
679                         err = blk_send_start_stop(q, bd_disk, 0x02);
680                         break;
681                 default:
682                         err = -ENOTTY;
683         }
684
685         return err;
686 }
687 EXPORT_SYMBOL(scsi_cmd_ioctl);
688
689 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
690 {
691         if (bd && bd == bd->bd_contains)
692                 return 0;
693
694         /* Actually none of these is particularly useful on a partition,
695          * but they are safe.
696          */
697         switch (cmd) {
698         case SCSI_IOCTL_GET_IDLUN:
699         case SCSI_IOCTL_GET_BUS_NUMBER:
700         case SCSI_IOCTL_GET_PCI:
701         case SCSI_IOCTL_PROBE_HOST:
702         case SG_GET_VERSION_NUM:
703         case SG_SET_TIMEOUT:
704         case SG_GET_TIMEOUT:
705         case SG_GET_RESERVED_SIZE:
706         case SG_SET_RESERVED_SIZE:
707         case SG_EMULATED_HOST:
708                 return 0;
709         case CDROM_GET_CAPABILITY:
710                 /* Keep this until we remove the printk below.  udev sends it
711                  * and we do not want to spam dmesg about it.   CD-ROMs do
712                  * not have partitions, so we get here only for disks.
713                  */
714                 return -ENOIOCTLCMD;
715         default:
716                 break;
717         }
718
719         if (capable(CAP_SYS_RAWIO))
720                 return 0;
721
722         /* In particular, rule out all resets and host-specific ioctls.  */
723         printk_ratelimited(KERN_WARNING
724                            "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
725
726         return -ENOIOCTLCMD;
727 }
728 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
729
730 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
731                        unsigned int cmd, void __user *arg)
732 {
733         int ret;
734
735         ret = scsi_verify_blk_ioctl(bd, cmd);
736         if (ret < 0)
737                 return ret;
738
739         return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
740 }
741 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
742
743 static int __init blk_scsi_ioctl_init(void)
744 {
745         blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
746         return 0;
747 }
748 fs_initcall(blk_scsi_ioctl_init);