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