Merge branch 'akpm' (fixes from Andrew)
[linux-drm-fsl-dcu.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         ssize_t ret = 0;
290         int writing = 0;
291         struct request *rq;
292         char sense[SCSI_SENSE_BUFFERSIZE];
293         struct bio *bio;
294
295         if (hdr->interface_id != 'S')
296                 return -EINVAL;
297         if (hdr->cmd_len > BLK_MAX_CDB)
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
315         rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
316         if (!rq)
317                 return -ENOMEM;
318
319         if (blk_fill_sghdr_rq(q, rq, hdr, mode)) {
320                 blk_put_request(rq);
321                 return -EFAULT;
322         }
323
324         if (hdr->iovec_count) {
325                 size_t iov_data_len;
326                 struct iovec *iov;
327
328                 ret = rw_copy_check_uvector(-1, hdr->dxferp, hdr->iovec_count,
329                                             0, NULL, &iov);
330                 if (ret < 0)
331                         goto out;
332
333                 iov_data_len = ret;
334                 ret = 0;
335
336                 /* SG_IO howto says that the shorter of the two wins */
337                 if (hdr->dxfer_len < iov_data_len) {
338                         hdr->iovec_count = iov_shorten(iov,
339                                                        hdr->iovec_count,
340                                                        hdr->dxfer_len);
341                         iov_data_len = hdr->dxfer_len;
342                 }
343
344                 ret = blk_rq_map_user_iov(q, rq, NULL, (struct sg_iovec *) iov,
345                                           hdr->iovec_count,
346                                           iov_data_len, GFP_KERNEL);
347                 kfree(iov);
348         } else if (hdr->dxfer_len)
349                 ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
350                                       GFP_KERNEL);
351
352         if (ret)
353                 goto out;
354
355         bio = rq->bio;
356         memset(sense, 0, sizeof(sense));
357         rq->sense = sense;
358         rq->sense_len = 0;
359         rq->retries = 0;
360
361         start_time = jiffies;
362
363         /* ignore return value. All information is passed back to caller
364          * (if he doesn't check that is his problem).
365          * N.B. a non-zero SCSI status is _not_ necessarily an error.
366          */
367         blk_execute_rq(q, bd_disk, rq, 0);
368
369         hdr->duration = jiffies_to_msecs(jiffies - start_time);
370
371         return blk_complete_sghdr_rq(rq, hdr, bio);
372 out:
373         blk_put_request(rq);
374         return ret;
375 }
376
377 /**
378  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
379  * @file:       file this ioctl operates on (optional)
380  * @q:          request queue to send scsi commands down
381  * @disk:       gendisk to operate on (option)
382  * @sic:        userspace structure describing the command to perform
383  *
384  * Send down the scsi command described by @sic to the device below
385  * the request queue @q.  If @file is non-NULL it's used to perform
386  * fine-grained permission checks that allow users to send down
387  * non-destructive SCSI commands.  If the caller has a struct gendisk
388  * available it should be passed in as @disk to allow the low level
389  * driver to use the information contained in it.  A non-NULL @disk
390  * is only allowed if the caller knows that the low level driver doesn't
391  * need it (e.g. in the scsi subsystem).
392  *
393  * Notes:
394  *   -  This interface is deprecated - users should use the SG_IO
395  *      interface instead, as this is a more flexible approach to
396  *      performing SCSI commands on a device.
397  *   -  The SCSI command length is determined by examining the 1st byte
398  *      of the given command. There is no way to override this.
399  *   -  Data transfers are limited to PAGE_SIZE
400  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
401  *      accommodate the sense buffer when an error occurs.
402  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
403  *      old code will not be surprised.
404  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
405  *      a negative return and the Unix error code in 'errno'.
406  *      If the SCSI command succeeds then 0 is returned.
407  *      Positive numbers returned are the compacted SCSI error codes (4
408  *      bytes in one int) where the lowest byte is the SCSI status.
409  */
410 #define OMAX_SB_LEN 16          /* For backward compatibility */
411 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
412                 struct scsi_ioctl_command __user *sic)
413 {
414         struct request *rq;
415         int err;
416         unsigned int in_len, out_len, bytes, opcode, cmdlen;
417         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
418
419         if (!sic)
420                 return -EINVAL;
421
422         /*
423          * get in an out lengths, verify they don't exceed a page worth of data
424          */
425         if (get_user(in_len, &sic->inlen))
426                 return -EFAULT;
427         if (get_user(out_len, &sic->outlen))
428                 return -EFAULT;
429         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
430                 return -EINVAL;
431         if (get_user(opcode, sic->data))
432                 return -EFAULT;
433
434         bytes = max(in_len, out_len);
435         if (bytes) {
436                 buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
437                 if (!buffer)
438                         return -ENOMEM;
439
440         }
441
442         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
443
444         cmdlen = COMMAND_SIZE(opcode);
445
446         /*
447          * get command and data to send to device, if any
448          */
449         err = -EFAULT;
450         rq->cmd_len = cmdlen;
451         if (copy_from_user(rq->cmd, sic->data, cmdlen))
452                 goto error;
453
454         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
455                 goto error;
456
457         err = blk_verify_command(rq->cmd, mode & FMODE_WRITE);
458         if (err)
459                 goto error;
460
461         /* default.  possible overriden later */
462         rq->retries = 5;
463
464         switch (opcode) {
465         case SEND_DIAGNOSTIC:
466         case FORMAT_UNIT:
467                 rq->timeout = FORMAT_UNIT_TIMEOUT;
468                 rq->retries = 1;
469                 break;
470         case START_STOP:
471                 rq->timeout = START_STOP_TIMEOUT;
472                 break;
473         case MOVE_MEDIUM:
474                 rq->timeout = MOVE_MEDIUM_TIMEOUT;
475                 break;
476         case READ_ELEMENT_STATUS:
477                 rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
478                 break;
479         case READ_DEFECT_DATA:
480                 rq->timeout = READ_DEFECT_DATA_TIMEOUT;
481                 rq->retries = 1;
482                 break;
483         default:
484                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
485                 break;
486         }
487
488         if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
489                 err = DRIVER_ERROR << 24;
490                 goto out;
491         }
492
493         memset(sense, 0, sizeof(sense));
494         rq->sense = sense;
495         rq->sense_len = 0;
496         rq->cmd_type = REQ_TYPE_BLOCK_PC;
497
498         blk_execute_rq(q, disk, rq, 0);
499
500 out:
501         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
502         if (err) {
503                 if (rq->sense_len && rq->sense) {
504                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
505                                 rq->sense_len : OMAX_SB_LEN;
506                         if (copy_to_user(sic->data, rq->sense, bytes))
507                                 err = -EFAULT;
508                 }
509         } else {
510                 if (copy_to_user(sic->data, buffer, out_len))
511                         err = -EFAULT;
512         }
513         
514 error:
515         kfree(buffer);
516         blk_put_request(rq);
517         return err;
518 }
519 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
520
521 /* Send basic block requests */
522 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
523                               int cmd, int data)
524 {
525         struct request *rq;
526         int err;
527
528         rq = blk_get_request(q, WRITE, __GFP_WAIT);
529         rq->cmd_type = REQ_TYPE_BLOCK_PC;
530         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
531         rq->cmd[0] = cmd;
532         rq->cmd[4] = data;
533         rq->cmd_len = 6;
534         err = blk_execute_rq(q, bd_disk, rq, 0);
535         blk_put_request(rq);
536
537         return err;
538 }
539
540 static inline int blk_send_start_stop(struct request_queue *q,
541                                       struct gendisk *bd_disk, int data)
542 {
543         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
544 }
545
546 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
547                    unsigned int cmd, void __user *arg)
548 {
549         int err;
550
551         if (!q)
552                 return -ENXIO;
553
554         switch (cmd) {
555                 /*
556                  * new sgv3 interface
557                  */
558                 case SG_GET_VERSION_NUM:
559                         err = sg_get_version(arg);
560                         break;
561                 case SCSI_IOCTL_GET_IDLUN:
562                         err = scsi_get_idlun(q, arg);
563                         break;
564                 case SCSI_IOCTL_GET_BUS_NUMBER:
565                         err = scsi_get_bus(q, arg);
566                         break;
567                 case SG_SET_TIMEOUT:
568                         err = sg_set_timeout(q, arg);
569                         break;
570                 case SG_GET_TIMEOUT:
571                         err = sg_get_timeout(q);
572                         break;
573                 case SG_GET_RESERVED_SIZE:
574                         err = sg_get_reserved_size(q, arg);
575                         break;
576                 case SG_SET_RESERVED_SIZE:
577                         err = sg_set_reserved_size(q, arg);
578                         break;
579                 case SG_EMULATED_HOST:
580                         err = sg_emulated_host(q, arg);
581                         break;
582                 case SG_IO: {
583                         struct sg_io_hdr hdr;
584
585                         err = -EFAULT;
586                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
587                                 break;
588                         err = sg_io(q, bd_disk, &hdr, mode);
589                         if (err == -EFAULT)
590                                 break;
591
592                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
593                                 err = -EFAULT;
594                         break;
595                 }
596                 case CDROM_SEND_PACKET: {
597                         struct cdrom_generic_command cgc;
598                         struct sg_io_hdr hdr;
599
600                         err = -EFAULT;
601                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
602                                 break;
603                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
604                         memset(&hdr, 0, sizeof(hdr));
605                         hdr.interface_id = 'S';
606                         hdr.cmd_len = sizeof(cgc.cmd);
607                         hdr.dxfer_len = cgc.buflen;
608                         err = 0;
609                         switch (cgc.data_direction) {
610                                 case CGC_DATA_UNKNOWN:
611                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
612                                         break;
613                                 case CGC_DATA_WRITE:
614                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
615                                         break;
616                                 case CGC_DATA_READ:
617                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
618                                         break;
619                                 case CGC_DATA_NONE:
620                                         hdr.dxfer_direction = SG_DXFER_NONE;
621                                         break;
622                                 default:
623                                         err = -EINVAL;
624                         }
625                         if (err)
626                                 break;
627
628                         hdr.dxferp = cgc.buffer;
629                         hdr.sbp = cgc.sense;
630                         if (hdr.sbp)
631                                 hdr.mx_sb_len = sizeof(struct request_sense);
632                         hdr.timeout = jiffies_to_msecs(cgc.timeout);
633                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
634                         hdr.cmd_len = sizeof(cgc.cmd);
635
636                         err = sg_io(q, bd_disk, &hdr, mode);
637                         if (err == -EFAULT)
638                                 break;
639
640                         if (hdr.status)
641                                 err = -EIO;
642
643                         cgc.stat = err;
644                         cgc.buflen = hdr.resid;
645                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
646                                 err = -EFAULT;
647
648                         break;
649                 }
650
651                 /*
652                  * old junk scsi send command ioctl
653                  */
654                 case SCSI_IOCTL_SEND_COMMAND:
655                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
656                         err = -EINVAL;
657                         if (!arg)
658                                 break;
659
660                         err = sg_scsi_ioctl(q, bd_disk, mode, arg);
661                         break;
662                 case CDROMCLOSETRAY:
663                         err = blk_send_start_stop(q, bd_disk, 0x03);
664                         break;
665                 case CDROMEJECT:
666                         err = blk_send_start_stop(q, bd_disk, 0x02);
667                         break;
668                 default:
669                         err = -ENOTTY;
670         }
671
672         return err;
673 }
674 EXPORT_SYMBOL(scsi_cmd_ioctl);
675
676 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
677 {
678         if (bd && bd == bd->bd_contains)
679                 return 0;
680
681         /* Actually none of these is particularly useful on a partition,
682          * but they are safe.
683          */
684         switch (cmd) {
685         case SCSI_IOCTL_GET_IDLUN:
686         case SCSI_IOCTL_GET_BUS_NUMBER:
687         case SCSI_IOCTL_GET_PCI:
688         case SCSI_IOCTL_PROBE_HOST:
689         case SG_GET_VERSION_NUM:
690         case SG_SET_TIMEOUT:
691         case SG_GET_TIMEOUT:
692         case SG_GET_RESERVED_SIZE:
693         case SG_SET_RESERVED_SIZE:
694         case SG_EMULATED_HOST:
695                 return 0;
696         case CDROM_GET_CAPABILITY:
697                 /* Keep this until we remove the printk below.  udev sends it
698                  * and we do not want to spam dmesg about it.   CD-ROMs do
699                  * not have partitions, so we get here only for disks.
700                  */
701                 return -ENOIOCTLCMD;
702         default:
703                 break;
704         }
705
706         if (capable(CAP_SYS_RAWIO))
707                 return 0;
708
709         /* In particular, rule out all resets and host-specific ioctls.  */
710         printk_ratelimited(KERN_WARNING
711                            "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
712
713         return -ENOIOCTLCMD;
714 }
715 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
716
717 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
718                        unsigned int cmd, void __user *arg)
719 {
720         int ret;
721
722         ret = scsi_verify_blk_ioctl(bd, cmd);
723         if (ret < 0)
724                 return ret;
725
726         return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
727 }
728 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
729
730 static int __init blk_scsi_ioctl_init(void)
731 {
732         blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
733         return 0;
734 }
735 fs_initcall(blk_scsi_ioctl_init);