Merge tag 'xtensa-next-20130710' of git://github.com/czankel/xtensa-linux
[platform/adaptation/renesas_rcar/renesas_kernel.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 sg_get_reserved_size(struct request_queue *q, int __user *p)
86 {
87         unsigned val = min(q->sg_reserved_size, queue_max_sectors(q) << 9);
88
89         return put_user(val, p);
90 }
91
92 static int sg_set_reserved_size(struct request_queue *q, int __user *p)
93 {
94         int size, err = get_user(size, p);
95
96         if (err)
97                 return err;
98
99         if (size < 0)
100                 return -EINVAL;
101         if (size > (queue_max_sectors(q) << 9))
102                 size = queue_max_sectors(q) << 9;
103
104         q->sg_reserved_size = size;
105         return 0;
106 }
107
108 /*
109  * will always return that we are ATAPI even for a real SCSI drive, I'm not
110  * so sure this is worth doing anything about (why would you care??)
111  */
112 static int sg_emulated_host(struct request_queue *q, int __user *p)
113 {
114         return put_user(1, p);
115 }
116
117 static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
118 {
119         /* Basic read-only commands */
120         __set_bit(TEST_UNIT_READY, filter->read_ok);
121         __set_bit(REQUEST_SENSE, filter->read_ok);
122         __set_bit(READ_6, filter->read_ok);
123         __set_bit(READ_10, filter->read_ok);
124         __set_bit(READ_12, filter->read_ok);
125         __set_bit(READ_16, filter->read_ok);
126         __set_bit(READ_BUFFER, filter->read_ok);
127         __set_bit(READ_DEFECT_DATA, filter->read_ok);
128         __set_bit(READ_CAPACITY, filter->read_ok);
129         __set_bit(READ_LONG, filter->read_ok);
130         __set_bit(INQUIRY, filter->read_ok);
131         __set_bit(MODE_SENSE, filter->read_ok);
132         __set_bit(MODE_SENSE_10, filter->read_ok);
133         __set_bit(LOG_SENSE, filter->read_ok);
134         __set_bit(START_STOP, filter->read_ok);
135         __set_bit(GPCMD_VERIFY_10, filter->read_ok);
136         __set_bit(VERIFY_16, filter->read_ok);
137         __set_bit(REPORT_LUNS, filter->read_ok);
138         __set_bit(SERVICE_ACTION_IN, filter->read_ok);
139         __set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
140         __set_bit(MAINTENANCE_IN, filter->read_ok);
141         __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
142
143         /* Audio CD commands */
144         __set_bit(GPCMD_PLAY_CD, filter->read_ok);
145         __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
146         __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
147         __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
148         __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
149
150         /* CD/DVD data reading */
151         __set_bit(GPCMD_READ_CD, filter->read_ok);
152         __set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
153         __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
154         __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
155         __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
156         __set_bit(GPCMD_READ_HEADER, filter->read_ok);
157         __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
158         __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
159         __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
160         __set_bit(GPCMD_REPORT_KEY, filter->read_ok);
161         __set_bit(GPCMD_SCAN, filter->read_ok);
162         __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
163         __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
164         __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
165         __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
166         __set_bit(GPCMD_SEEK, filter->read_ok);
167         __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
168
169         /* Basic writing commands */
170         __set_bit(WRITE_6, filter->write_ok);
171         __set_bit(WRITE_10, filter->write_ok);
172         __set_bit(WRITE_VERIFY, filter->write_ok);
173         __set_bit(WRITE_12, filter->write_ok);
174         __set_bit(WRITE_VERIFY_12, filter->write_ok);
175         __set_bit(WRITE_16, filter->write_ok);
176         __set_bit(WRITE_LONG, filter->write_ok);
177         __set_bit(WRITE_LONG_2, filter->write_ok);
178         __set_bit(ERASE, filter->write_ok);
179         __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
180         __set_bit(MODE_SELECT, filter->write_ok);
181         __set_bit(LOG_SELECT, filter->write_ok);
182         __set_bit(GPCMD_BLANK, filter->write_ok);
183         __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
184         __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
185         __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
186         __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
187         __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
188         __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
189         __set_bit(GPCMD_SEND_EVENT, filter->write_ok);
190         __set_bit(GPCMD_SEND_KEY, filter->write_ok);
191         __set_bit(GPCMD_SEND_OPC, filter->write_ok);
192         __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
193         __set_bit(GPCMD_SET_SPEED, filter->write_ok);
194         __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
195         __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
196         __set_bit(GPCMD_SET_STREAMING, filter->write_ok);
197         __set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
198 }
199
200 int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
201 {
202         struct blk_cmd_filter *filter = &blk_default_cmd_filter;
203
204         /* root can do any command. */
205         if (capable(CAP_SYS_RAWIO))
206                 return 0;
207
208         /* if there's no filter set, assume we're filtering everything out */
209         if (!filter)
210                 return -EPERM;
211
212         /* Anybody who can open the device can do a read-safe command */
213         if (test_bit(cmd[0], filter->read_ok))
214                 return 0;
215
216         /* Write-safe commands require a writable open */
217         if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
218                 return 0;
219
220         return -EPERM;
221 }
222 EXPORT_SYMBOL(blk_verify_command);
223
224 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
225                              struct sg_io_hdr *hdr, fmode_t mode)
226 {
227         if (copy_from_user(rq->cmd, hdr->cmdp, hdr->cmd_len))
228                 return -EFAULT;
229         if (blk_verify_command(rq->cmd, mode & FMODE_WRITE))
230                 return -EPERM;
231
232         /*
233          * fill in request structure
234          */
235         rq->cmd_len = hdr->cmd_len;
236         rq->cmd_type = REQ_TYPE_BLOCK_PC;
237
238         rq->timeout = msecs_to_jiffies(hdr->timeout);
239         if (!rq->timeout)
240                 rq->timeout = q->sg_timeout;
241         if (!rq->timeout)
242                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
243         if (rq->timeout < BLK_MIN_SG_TIMEOUT)
244                 rq->timeout = BLK_MIN_SG_TIMEOUT;
245
246         return 0;
247 }
248
249 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
250                                  struct bio *bio)
251 {
252         int r, ret = 0;
253
254         /*
255          * fill in all the output members
256          */
257         hdr->status = rq->errors & 0xff;
258         hdr->masked_status = status_byte(rq->errors);
259         hdr->msg_status = msg_byte(rq->errors);
260         hdr->host_status = host_byte(rq->errors);
261         hdr->driver_status = driver_byte(rq->errors);
262         hdr->info = 0;
263         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
264                 hdr->info |= SG_INFO_CHECK;
265         hdr->resid = rq->resid_len;
266         hdr->sb_len_wr = 0;
267
268         if (rq->sense_len && hdr->sbp) {
269                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
270
271                 if (!copy_to_user(hdr->sbp, rq->sense, len))
272                         hdr->sb_len_wr = len;
273                 else
274                         ret = -EFAULT;
275         }
276
277         r = blk_rq_unmap_user(bio);
278         if (!ret)
279                 ret = r;
280         blk_put_request(rq);
281
282         return ret;
283 }
284
285 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
286                 struct sg_io_hdr *hdr, fmode_t mode)
287 {
288         unsigned long start_time;
289         int writing = 0, ret = 0;
290         struct request *rq;
291         char sense[SCSI_SENSE_BUFFERSIZE];
292         struct bio *bio;
293
294         if (hdr->interface_id != 'S')
295                 return -EINVAL;
296         if (hdr->cmd_len > BLK_MAX_CDB)
297                 return -EINVAL;
298
299         if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
300                 return -EIO;
301
302         if (hdr->dxfer_len)
303                 switch (hdr->dxfer_direction) {
304                 default:
305                         return -EINVAL;
306                 case SG_DXFER_TO_DEV:
307                         writing = 1;
308                         break;
309                 case SG_DXFER_TO_FROM_DEV:
310                 case SG_DXFER_FROM_DEV:
311                         break;
312                 }
313
314         rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
315         if (!rq)
316                 return -ENOMEM;
317
318         if (blk_fill_sghdr_rq(q, rq, hdr, mode)) {
319                 blk_put_request(rq);
320                 return -EFAULT;
321         }
322
323         if (hdr->iovec_count) {
324                 const int size = sizeof(struct sg_iovec) * hdr->iovec_count;
325                 size_t iov_data_len;
326                 struct sg_iovec *sg_iov;
327                 struct iovec *iov;
328                 int i;
329
330                 sg_iov = kmalloc(size, GFP_KERNEL);
331                 if (!sg_iov) {
332                         ret = -ENOMEM;
333                         goto out;
334                 }
335
336                 if (copy_from_user(sg_iov, hdr->dxferp, size)) {
337                         kfree(sg_iov);
338                         ret = -EFAULT;
339                         goto out;
340                 }
341
342                 /*
343                  * Sum up the vecs, making sure they don't overflow
344                  */
345                 iov = (struct iovec *) sg_iov;
346                 iov_data_len = 0;
347                 for (i = 0; i < hdr->iovec_count; i++) {
348                         if (iov_data_len + iov[i].iov_len < iov_data_len) {
349                                 kfree(sg_iov);
350                                 ret = -EINVAL;
351                                 goto out;
352                         }
353                         iov_data_len += iov[i].iov_len;
354                 }
355
356                 /* SG_IO howto says that the shorter of the two wins */
357                 if (hdr->dxfer_len < iov_data_len) {
358                         hdr->iovec_count = iov_shorten(iov,
359                                                        hdr->iovec_count,
360                                                        hdr->dxfer_len);
361                         iov_data_len = hdr->dxfer_len;
362                 }
363
364                 ret = blk_rq_map_user_iov(q, rq, NULL, sg_iov, hdr->iovec_count,
365                                           iov_data_len, GFP_KERNEL);
366                 kfree(sg_iov);
367         } else if (hdr->dxfer_len)
368                 ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
369                                       GFP_KERNEL);
370
371         if (ret)
372                 goto out;
373
374         bio = rq->bio;
375         memset(sense, 0, sizeof(sense));
376         rq->sense = sense;
377         rq->sense_len = 0;
378         rq->retries = 0;
379
380         start_time = jiffies;
381
382         /* ignore return value. All information is passed back to caller
383          * (if he doesn't check that is his problem).
384          * N.B. a non-zero SCSI status is _not_ necessarily an error.
385          */
386         blk_execute_rq(q, bd_disk, rq, 0);
387
388         hdr->duration = jiffies_to_msecs(jiffies - start_time);
389
390         return blk_complete_sghdr_rq(rq, hdr, bio);
391 out:
392         blk_put_request(rq);
393         return ret;
394 }
395
396 /**
397  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
398  * @file:       file this ioctl operates on (optional)
399  * @q:          request queue to send scsi commands down
400  * @disk:       gendisk to operate on (option)
401  * @sic:        userspace structure describing the command to perform
402  *
403  * Send down the scsi command described by @sic to the device below
404  * the request queue @q.  If @file is non-NULL it's used to perform
405  * fine-grained permission checks that allow users to send down
406  * non-destructive SCSI commands.  If the caller has a struct gendisk
407  * available it should be passed in as @disk to allow the low level
408  * driver to use the information contained in it.  A non-NULL @disk
409  * is only allowed if the caller knows that the low level driver doesn't
410  * need it (e.g. in the scsi subsystem).
411  *
412  * Notes:
413  *   -  This interface is deprecated - users should use the SG_IO
414  *      interface instead, as this is a more flexible approach to
415  *      performing SCSI commands on a device.
416  *   -  The SCSI command length is determined by examining the 1st byte
417  *      of the given command. There is no way to override this.
418  *   -  Data transfers are limited to PAGE_SIZE
419  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
420  *      accommodate the sense buffer when an error occurs.
421  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
422  *      old code will not be surprised.
423  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
424  *      a negative return and the Unix error code in 'errno'.
425  *      If the SCSI command succeeds then 0 is returned.
426  *      Positive numbers returned are the compacted SCSI error codes (4
427  *      bytes in one int) where the lowest byte is the SCSI status.
428  */
429 #define OMAX_SB_LEN 16          /* For backward compatibility */
430 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
431                 struct scsi_ioctl_command __user *sic)
432 {
433         struct request *rq;
434         int err;
435         unsigned int in_len, out_len, bytes, opcode, cmdlen;
436         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
437
438         if (!sic)
439                 return -EINVAL;
440
441         /*
442          * get in an out lengths, verify they don't exceed a page worth of data
443          */
444         if (get_user(in_len, &sic->inlen))
445                 return -EFAULT;
446         if (get_user(out_len, &sic->outlen))
447                 return -EFAULT;
448         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
449                 return -EINVAL;
450         if (get_user(opcode, sic->data))
451                 return -EFAULT;
452
453         bytes = max(in_len, out_len);
454         if (bytes) {
455                 buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
456                 if (!buffer)
457                         return -ENOMEM;
458
459         }
460
461         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
462
463         cmdlen = COMMAND_SIZE(opcode);
464
465         /*
466          * get command and data to send to device, if any
467          */
468         err = -EFAULT;
469         rq->cmd_len = cmdlen;
470         if (copy_from_user(rq->cmd, sic->data, cmdlen))
471                 goto error;
472
473         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
474                 goto error;
475
476         err = blk_verify_command(rq->cmd, mode & FMODE_WRITE);
477         if (err)
478                 goto error;
479
480         /* default.  possible overriden later */
481         rq->retries = 5;
482
483         switch (opcode) {
484         case SEND_DIAGNOSTIC:
485         case FORMAT_UNIT:
486                 rq->timeout = FORMAT_UNIT_TIMEOUT;
487                 rq->retries = 1;
488                 break;
489         case START_STOP:
490                 rq->timeout = START_STOP_TIMEOUT;
491                 break;
492         case MOVE_MEDIUM:
493                 rq->timeout = MOVE_MEDIUM_TIMEOUT;
494                 break;
495         case READ_ELEMENT_STATUS:
496                 rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
497                 break;
498         case READ_DEFECT_DATA:
499                 rq->timeout = READ_DEFECT_DATA_TIMEOUT;
500                 rq->retries = 1;
501                 break;
502         default:
503                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
504                 break;
505         }
506
507         if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
508                 err = DRIVER_ERROR << 24;
509                 goto out;
510         }
511
512         memset(sense, 0, sizeof(sense));
513         rq->sense = sense;
514         rq->sense_len = 0;
515         rq->cmd_type = REQ_TYPE_BLOCK_PC;
516
517         blk_execute_rq(q, disk, rq, 0);
518
519 out:
520         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
521         if (err) {
522                 if (rq->sense_len && rq->sense) {
523                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
524                                 rq->sense_len : OMAX_SB_LEN;
525                         if (copy_to_user(sic->data, rq->sense, bytes))
526                                 err = -EFAULT;
527                 }
528         } else {
529                 if (copy_to_user(sic->data, buffer, out_len))
530                         err = -EFAULT;
531         }
532         
533 error:
534         kfree(buffer);
535         blk_put_request(rq);
536         return err;
537 }
538 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
539
540 /* Send basic block requests */
541 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
542                               int cmd, int data)
543 {
544         struct request *rq;
545         int err;
546
547         rq = blk_get_request(q, WRITE, __GFP_WAIT);
548         rq->cmd_type = REQ_TYPE_BLOCK_PC;
549         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
550         rq->cmd[0] = cmd;
551         rq->cmd[4] = data;
552         rq->cmd_len = 6;
553         err = blk_execute_rq(q, bd_disk, rq, 0);
554         blk_put_request(rq);
555
556         return err;
557 }
558
559 static inline int blk_send_start_stop(struct request_queue *q,
560                                       struct gendisk *bd_disk, int data)
561 {
562         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
563 }
564
565 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
566                    unsigned int cmd, void __user *arg)
567 {
568         int err;
569
570         if (!q)
571                 return -ENXIO;
572
573         switch (cmd) {
574                 /*
575                  * new sgv3 interface
576                  */
577                 case SG_GET_VERSION_NUM:
578                         err = sg_get_version(arg);
579                         break;
580                 case SCSI_IOCTL_GET_IDLUN:
581                         err = scsi_get_idlun(q, arg);
582                         break;
583                 case SCSI_IOCTL_GET_BUS_NUMBER:
584                         err = scsi_get_bus(q, arg);
585                         break;
586                 case SG_SET_TIMEOUT:
587                         err = sg_set_timeout(q, arg);
588                         break;
589                 case SG_GET_TIMEOUT:
590                         err = sg_get_timeout(q);
591                         break;
592                 case SG_GET_RESERVED_SIZE:
593                         err = sg_get_reserved_size(q, arg);
594                         break;
595                 case SG_SET_RESERVED_SIZE:
596                         err = sg_set_reserved_size(q, arg);
597                         break;
598                 case SG_EMULATED_HOST:
599                         err = sg_emulated_host(q, arg);
600                         break;
601                 case SG_IO: {
602                         struct sg_io_hdr hdr;
603
604                         err = -EFAULT;
605                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
606                                 break;
607                         err = sg_io(q, bd_disk, &hdr, mode);
608                         if (err == -EFAULT)
609                                 break;
610
611                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
612                                 err = -EFAULT;
613                         break;
614                 }
615                 case CDROM_SEND_PACKET: {
616                         struct cdrom_generic_command cgc;
617                         struct sg_io_hdr hdr;
618
619                         err = -EFAULT;
620                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
621                                 break;
622                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
623                         memset(&hdr, 0, sizeof(hdr));
624                         hdr.interface_id = 'S';
625                         hdr.cmd_len = sizeof(cgc.cmd);
626                         hdr.dxfer_len = cgc.buflen;
627                         err = 0;
628                         switch (cgc.data_direction) {
629                                 case CGC_DATA_UNKNOWN:
630                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
631                                         break;
632                                 case CGC_DATA_WRITE:
633                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
634                                         break;
635                                 case CGC_DATA_READ:
636                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
637                                         break;
638                                 case CGC_DATA_NONE:
639                                         hdr.dxfer_direction = SG_DXFER_NONE;
640                                         break;
641                                 default:
642                                         err = -EINVAL;
643                         }
644                         if (err)
645                                 break;
646
647                         hdr.dxferp = cgc.buffer;
648                         hdr.sbp = cgc.sense;
649                         if (hdr.sbp)
650                                 hdr.mx_sb_len = sizeof(struct request_sense);
651                         hdr.timeout = jiffies_to_msecs(cgc.timeout);
652                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
653                         hdr.cmd_len = sizeof(cgc.cmd);
654
655                         err = sg_io(q, bd_disk, &hdr, mode);
656                         if (err == -EFAULT)
657                                 break;
658
659                         if (hdr.status)
660                                 err = -EIO;
661
662                         cgc.stat = err;
663                         cgc.buflen = hdr.resid;
664                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
665                                 err = -EFAULT;
666
667                         break;
668                 }
669
670                 /*
671                  * old junk scsi send command ioctl
672                  */
673                 case SCSI_IOCTL_SEND_COMMAND:
674                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
675                         err = -EINVAL;
676                         if (!arg)
677                                 break;
678
679                         err = sg_scsi_ioctl(q, bd_disk, mode, arg);
680                         break;
681                 case CDROMCLOSETRAY:
682                         err = blk_send_start_stop(q, bd_disk, 0x03);
683                         break;
684                 case CDROMEJECT:
685                         err = blk_send_start_stop(q, bd_disk, 0x02);
686                         break;
687                 default:
688                         err = -ENOTTY;
689         }
690
691         return err;
692 }
693 EXPORT_SYMBOL(scsi_cmd_ioctl);
694
695 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
696 {
697         if (bd && bd == bd->bd_contains)
698                 return 0;
699
700         /* Actually none of these is particularly useful on a partition,
701          * but they are safe.
702          */
703         switch (cmd) {
704         case SCSI_IOCTL_GET_IDLUN:
705         case SCSI_IOCTL_GET_BUS_NUMBER:
706         case SCSI_IOCTL_GET_PCI:
707         case SCSI_IOCTL_PROBE_HOST:
708         case SG_GET_VERSION_NUM:
709         case SG_SET_TIMEOUT:
710         case SG_GET_TIMEOUT:
711         case SG_GET_RESERVED_SIZE:
712         case SG_SET_RESERVED_SIZE:
713         case SG_EMULATED_HOST:
714                 return 0;
715         case CDROM_GET_CAPABILITY:
716                 /* Keep this until we remove the printk below.  udev sends it
717                  * and we do not want to spam dmesg about it.   CD-ROMs do
718                  * not have partitions, so we get here only for disks.
719                  */
720                 return -ENOIOCTLCMD;
721         default:
722                 break;
723         }
724
725         if (capable(CAP_SYS_RAWIO))
726                 return 0;
727
728         /* In particular, rule out all resets and host-specific ioctls.  */
729         printk_ratelimited(KERN_WARNING
730                            "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
731
732         return -ENOIOCTLCMD;
733 }
734 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
735
736 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
737                        unsigned int cmd, void __user *arg)
738 {
739         int ret;
740
741         ret = scsi_verify_blk_ioctl(bd, cmd);
742         if (ret < 0)
743                 return ret;
744
745         return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
746 }
747 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
748
749 static int __init blk_scsi_ioctl_init(void)
750 {
751         blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
752         return 0;
753 }
754 fs_initcall(blk_scsi_ioctl_init);