Merge branch 'for-4.0' of git://linux-nfs.org/~bfields/linux
[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 = rw_copy_check_uvector(-1, hdr->dxferp, hdr->iovec_count,
339                                             0, NULL, &iov);
340                 if (ret < 0) {
341                         kfree(iov);
342                         goto out_free_cdb;
343                 }
344
345                 /* SG_IO howto says that the shorter of the two wins */
346                 iov_iter_init(&i, rq_data_dir(rq), iov, hdr->iovec_count,
347                               min_t(unsigned, ret, hdr->dxfer_len));
348
349                 ret = blk_rq_map_user_iov(q, rq, NULL, &i, GFP_KERNEL);
350                 kfree(iov);
351         } else if (hdr->dxfer_len)
352                 ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
353                                       GFP_KERNEL);
354
355         if (ret)
356                 goto out_free_cdb;
357
358         bio = rq->bio;
359         memset(sense, 0, sizeof(sense));
360         rq->sense = sense;
361         rq->sense_len = 0;
362         rq->retries = 0;
363
364         start_time = jiffies;
365
366         /* ignore return value. All information is passed back to caller
367          * (if he doesn't check that is his problem).
368          * N.B. a non-zero SCSI status is _not_ necessarily an error.
369          */
370         blk_execute_rq(q, bd_disk, rq, at_head);
371
372         hdr->duration = jiffies_to_msecs(jiffies - start_time);
373
374         ret = blk_complete_sghdr_rq(rq, hdr, bio);
375
376 out_free_cdb:
377         if (rq->cmd != rq->__cmd)
378                 kfree(rq->cmd);
379 out_put_request:
380         blk_put_request(rq);
381         return ret;
382 }
383
384 /**
385  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
386  * @file:       file this ioctl operates on (optional)
387  * @q:          request queue to send scsi commands down
388  * @disk:       gendisk to operate on (option)
389  * @sic:        userspace structure describing the command to perform
390  *
391  * Send down the scsi command described by @sic to the device below
392  * the request queue @q.  If @file is non-NULL it's used to perform
393  * fine-grained permission checks that allow users to send down
394  * non-destructive SCSI commands.  If the caller has a struct gendisk
395  * available it should be passed in as @disk to allow the low level
396  * driver to use the information contained in it.  A non-NULL @disk
397  * is only allowed if the caller knows that the low level driver doesn't
398  * need it (e.g. in the scsi subsystem).
399  *
400  * Notes:
401  *   -  This interface is deprecated - users should use the SG_IO
402  *      interface instead, as this is a more flexible approach to
403  *      performing SCSI commands on a device.
404  *   -  The SCSI command length is determined by examining the 1st byte
405  *      of the given command. There is no way to override this.
406  *   -  Data transfers are limited to PAGE_SIZE
407  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
408  *      accommodate the sense buffer when an error occurs.
409  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
410  *      old code will not be surprised.
411  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
412  *      a negative return and the Unix error code in 'errno'.
413  *      If the SCSI command succeeds then 0 is returned.
414  *      Positive numbers returned are the compacted SCSI error codes (4
415  *      bytes in one int) where the lowest byte is the SCSI status.
416  */
417 #define OMAX_SB_LEN 16          /* For backward compatibility */
418 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
419                 struct scsi_ioctl_command __user *sic)
420 {
421         struct request *rq;
422         int err;
423         unsigned int in_len, out_len, bytes, opcode, cmdlen;
424         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
425
426         if (!sic)
427                 return -EINVAL;
428
429         /*
430          * get in an out lengths, verify they don't exceed a page worth of data
431          */
432         if (get_user(in_len, &sic->inlen))
433                 return -EFAULT;
434         if (get_user(out_len, &sic->outlen))
435                 return -EFAULT;
436         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
437                 return -EINVAL;
438         if (get_user(opcode, sic->data))
439                 return -EFAULT;
440
441         bytes = max(in_len, out_len);
442         if (bytes) {
443                 buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
444                 if (!buffer)
445                         return -ENOMEM;
446
447         }
448
449         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
450         if (IS_ERR(rq)) {
451                 err = PTR_ERR(rq);
452                 goto error_free_buffer;
453         }
454         blk_rq_set_block_pc(rq);
455
456         cmdlen = COMMAND_SIZE(opcode);
457
458         /*
459          * get command and data to send to device, if any
460          */
461         err = -EFAULT;
462         rq->cmd_len = cmdlen;
463         if (copy_from_user(rq->cmd, sic->data, cmdlen))
464                 goto error;
465
466         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
467                 goto error;
468
469         err = blk_verify_command(rq->cmd, mode & FMODE_WRITE);
470         if (err)
471                 goto error;
472
473         /* default.  possible overriden later */
474         rq->retries = 5;
475
476         switch (opcode) {
477         case SEND_DIAGNOSTIC:
478         case FORMAT_UNIT:
479                 rq->timeout = FORMAT_UNIT_TIMEOUT;
480                 rq->retries = 1;
481                 break;
482         case START_STOP:
483                 rq->timeout = START_STOP_TIMEOUT;
484                 break;
485         case MOVE_MEDIUM:
486                 rq->timeout = MOVE_MEDIUM_TIMEOUT;
487                 break;
488         case READ_ELEMENT_STATUS:
489                 rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
490                 break;
491         case READ_DEFECT_DATA:
492                 rq->timeout = READ_DEFECT_DATA_TIMEOUT;
493                 rq->retries = 1;
494                 break;
495         default:
496                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
497                 break;
498         }
499
500         if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
501                 err = DRIVER_ERROR << 24;
502                 goto error;
503         }
504
505         memset(sense, 0, sizeof(sense));
506         rq->sense = sense;
507         rq->sense_len = 0;
508
509         blk_execute_rq(q, disk, rq, 0);
510
511         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
512         if (err) {
513                 if (rq->sense_len && rq->sense) {
514                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
515                                 rq->sense_len : OMAX_SB_LEN;
516                         if (copy_to_user(sic->data, rq->sense, bytes))
517                                 err = -EFAULT;
518                 }
519         } else {
520                 if (copy_to_user(sic->data, buffer, out_len))
521                         err = -EFAULT;
522         }
523         
524 error:
525         blk_put_request(rq);
526
527 error_free_buffer:
528         kfree(buffer);
529
530         return err;
531 }
532 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
533
534 /* Send basic block requests */
535 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
536                               int cmd, int data)
537 {
538         struct request *rq;
539         int err;
540
541         rq = blk_get_request(q, WRITE, __GFP_WAIT);
542         if (IS_ERR(rq))
543                 return PTR_ERR(rq);
544         blk_rq_set_block_pc(rq);
545         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
546         rq->cmd[0] = cmd;
547         rq->cmd[4] = data;
548         rq->cmd_len = 6;
549         err = blk_execute_rq(q, bd_disk, rq, 0);
550         blk_put_request(rq);
551
552         return err;
553 }
554
555 static inline int blk_send_start_stop(struct request_queue *q,
556                                       struct gendisk *bd_disk, int data)
557 {
558         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
559 }
560
561 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
562                    unsigned int cmd, void __user *arg)
563 {
564         int err;
565
566         if (!q)
567                 return -ENXIO;
568
569         switch (cmd) {
570                 /*
571                  * new sgv3 interface
572                  */
573                 case SG_GET_VERSION_NUM:
574                         err = sg_get_version(arg);
575                         break;
576                 case SCSI_IOCTL_GET_IDLUN:
577                         err = scsi_get_idlun(q, arg);
578                         break;
579                 case SCSI_IOCTL_GET_BUS_NUMBER:
580                         err = scsi_get_bus(q, arg);
581                         break;
582                 case SG_SET_TIMEOUT:
583                         err = sg_set_timeout(q, arg);
584                         break;
585                 case SG_GET_TIMEOUT:
586                         err = sg_get_timeout(q);
587                         break;
588                 case SG_GET_RESERVED_SIZE:
589                         err = sg_get_reserved_size(q, arg);
590                         break;
591                 case SG_SET_RESERVED_SIZE:
592                         err = sg_set_reserved_size(q, arg);
593                         break;
594                 case SG_EMULATED_HOST:
595                         err = sg_emulated_host(q, arg);
596                         break;
597                 case SG_IO: {
598                         struct sg_io_hdr hdr;
599
600                         err = -EFAULT;
601                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
602                                 break;
603                         err = sg_io(q, bd_disk, &hdr, mode);
604                         if (err == -EFAULT)
605                                 break;
606
607                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
608                                 err = -EFAULT;
609                         break;
610                 }
611                 case CDROM_SEND_PACKET: {
612                         struct cdrom_generic_command cgc;
613                         struct sg_io_hdr hdr;
614
615                         err = -EFAULT;
616                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
617                                 break;
618                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
619                         memset(&hdr, 0, sizeof(hdr));
620                         hdr.interface_id = 'S';
621                         hdr.cmd_len = sizeof(cgc.cmd);
622                         hdr.dxfer_len = cgc.buflen;
623                         err = 0;
624                         switch (cgc.data_direction) {
625                                 case CGC_DATA_UNKNOWN:
626                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
627                                         break;
628                                 case CGC_DATA_WRITE:
629                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
630                                         break;
631                                 case CGC_DATA_READ:
632                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
633                                         break;
634                                 case CGC_DATA_NONE:
635                                         hdr.dxfer_direction = SG_DXFER_NONE;
636                                         break;
637                                 default:
638                                         err = -EINVAL;
639                         }
640                         if (err)
641                                 break;
642
643                         hdr.dxferp = cgc.buffer;
644                         hdr.sbp = cgc.sense;
645                         if (hdr.sbp)
646                                 hdr.mx_sb_len = sizeof(struct request_sense);
647                         hdr.timeout = jiffies_to_msecs(cgc.timeout);
648                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
649                         hdr.cmd_len = sizeof(cgc.cmd);
650
651                         err = sg_io(q, bd_disk, &hdr, mode);
652                         if (err == -EFAULT)
653                                 break;
654
655                         if (hdr.status)
656                                 err = -EIO;
657
658                         cgc.stat = err;
659                         cgc.buflen = hdr.resid;
660                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
661                                 err = -EFAULT;
662
663                         break;
664                 }
665
666                 /*
667                  * old junk scsi send command ioctl
668                  */
669                 case SCSI_IOCTL_SEND_COMMAND:
670                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
671                         err = -EINVAL;
672                         if (!arg)
673                                 break;
674
675                         err = sg_scsi_ioctl(q, bd_disk, mode, arg);
676                         break;
677                 case CDROMCLOSETRAY:
678                         err = blk_send_start_stop(q, bd_disk, 0x03);
679                         break;
680                 case CDROMEJECT:
681                         err = blk_send_start_stop(q, bd_disk, 0x02);
682                         break;
683                 default:
684                         err = -ENOTTY;
685         }
686
687         return err;
688 }
689 EXPORT_SYMBOL(scsi_cmd_ioctl);
690
691 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
692 {
693         if (bd && bd == bd->bd_contains)
694                 return 0;
695
696         /* Actually none of these is particularly useful on a partition,
697          * but they are safe.
698          */
699         switch (cmd) {
700         case SCSI_IOCTL_GET_IDLUN:
701         case SCSI_IOCTL_GET_BUS_NUMBER:
702         case SCSI_IOCTL_GET_PCI:
703         case SCSI_IOCTL_PROBE_HOST:
704         case SG_GET_VERSION_NUM:
705         case SG_SET_TIMEOUT:
706         case SG_GET_TIMEOUT:
707         case SG_GET_RESERVED_SIZE:
708         case SG_SET_RESERVED_SIZE:
709         case SG_EMULATED_HOST:
710                 return 0;
711         case CDROM_GET_CAPABILITY:
712                 /* Keep this until we remove the printk below.  udev sends it
713                  * and we do not want to spam dmesg about it.   CD-ROMs do
714                  * not have partitions, so we get here only for disks.
715                  */
716                 return -ENOIOCTLCMD;
717         default:
718                 break;
719         }
720
721         if (capable(CAP_SYS_RAWIO))
722                 return 0;
723
724         /* In particular, rule out all resets and host-specific ioctls.  */
725         printk_ratelimited(KERN_WARNING
726                            "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
727
728         return -ENOIOCTLCMD;
729 }
730 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
731
732 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
733                        unsigned int cmd, void __user *arg)
734 {
735         int ret;
736
737         ret = scsi_verify_blk_ioctl(bd, cmd);
738         if (ret < 0)
739                 return ret;
740
741         return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
742 }
743 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
744
745 static int __init blk_scsi_ioctl_init(void)
746 {
747         blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
748         return 0;
749 }
750 fs_initcall(blk_scsi_ioctl_init);