[BLOCK] scsi_ioctl: file can be NULL from ioctl_by_bdev()
[linux-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/completion.h>
25 #include <linux/cdrom.h>
26 #include <linux/slab.h>
27 #include <linux/times.h>
28 #include <asm/uaccess.h>
29
30 #include <scsi/scsi.h>
31 #include <scsi/scsi_ioctl.h>
32 #include <scsi/scsi_cmnd.h>
33
34 /* Command group 3 is reserved and should never be used.  */
35 const unsigned char scsi_command_size[8] =
36 {
37         6, 10, 10, 12,
38         16, 12, 10, 10
39 };
40
41 EXPORT_SYMBOL(scsi_command_size);
42
43 #define BLK_DEFAULT_TIMEOUT     (60 * HZ)
44
45 #include <scsi/sg.h>
46
47 static int sg_get_version(int __user *p)
48 {
49         static const int sg_version_num = 30527;
50         return put_user(sg_version_num, p);
51 }
52
53 static int scsi_get_idlun(request_queue_t *q, int __user *p)
54 {
55         return put_user(0, p);
56 }
57
58 static int scsi_get_bus(request_queue_t *q, int __user *p)
59 {
60         return put_user(0, p);
61 }
62
63 static int sg_get_timeout(request_queue_t *q)
64 {
65         return q->sg_timeout / (HZ / USER_HZ);
66 }
67
68 static int sg_set_timeout(request_queue_t *q, int __user *p)
69 {
70         int timeout, err = get_user(timeout, p);
71
72         if (!err)
73                 q->sg_timeout = timeout * (HZ / USER_HZ);
74
75         return err;
76 }
77
78 static int sg_get_reserved_size(request_queue_t *q, int __user *p)
79 {
80         return put_user(q->sg_reserved_size, p);
81 }
82
83 static int sg_set_reserved_size(request_queue_t *q, int __user *p)
84 {
85         int size, err = get_user(size, p);
86
87         if (err)
88                 return err;
89
90         if (size < 0)
91                 return -EINVAL;
92         if (size > (q->max_sectors << 9))
93                 size = q->max_sectors << 9;
94
95         q->sg_reserved_size = size;
96         return 0;
97 }
98
99 /*
100  * will always return that we are ATAPI even for a real SCSI drive, I'm not
101  * so sure this is worth doing anything about (why would you care??)
102  */
103 static int sg_emulated_host(request_queue_t *q, int __user *p)
104 {
105         return put_user(1, p);
106 }
107
108 #define CMD_READ_SAFE   0x01
109 #define CMD_WRITE_SAFE  0x02
110 #define CMD_WARNED      0x04
111 #define safe_for_read(cmd)      [cmd] = CMD_READ_SAFE
112 #define safe_for_write(cmd)     [cmd] = CMD_WRITE_SAFE
113
114 static int verify_command(struct file *file, unsigned char *cmd)
115 {
116         static unsigned char cmd_type[256] = {
117
118                 /* Basic read-only commands */
119                 safe_for_read(TEST_UNIT_READY),
120                 safe_for_read(REQUEST_SENSE),
121                 safe_for_read(READ_6),
122                 safe_for_read(READ_10),
123                 safe_for_read(READ_12),
124                 safe_for_read(READ_16),
125                 safe_for_read(READ_BUFFER),
126                 safe_for_read(READ_DEFECT_DATA),
127                 safe_for_read(READ_LONG),
128                 safe_for_read(INQUIRY),
129                 safe_for_read(MODE_SENSE),
130                 safe_for_read(MODE_SENSE_10),
131                 safe_for_read(LOG_SENSE),
132                 safe_for_read(START_STOP),
133                 safe_for_read(GPCMD_VERIFY_10),
134                 safe_for_read(VERIFY_16),
135
136                 /* Audio CD commands */
137                 safe_for_read(GPCMD_PLAY_CD),
138                 safe_for_read(GPCMD_PLAY_AUDIO_10),
139                 safe_for_read(GPCMD_PLAY_AUDIO_MSF),
140                 safe_for_read(GPCMD_PLAY_AUDIO_TI),
141                 safe_for_read(GPCMD_PAUSE_RESUME),
142
143                 /* CD/DVD data reading */
144                 safe_for_read(GPCMD_READ_BUFFER_CAPACITY),
145                 safe_for_read(GPCMD_READ_CD),
146                 safe_for_read(GPCMD_READ_CD_MSF),
147                 safe_for_read(GPCMD_READ_DISC_INFO),
148                 safe_for_read(GPCMD_READ_CDVD_CAPACITY),
149                 safe_for_read(GPCMD_READ_DVD_STRUCTURE),
150                 safe_for_read(GPCMD_READ_HEADER),
151                 safe_for_read(GPCMD_READ_TRACK_RZONE_INFO),
152                 safe_for_read(GPCMD_READ_SUBCHANNEL),
153                 safe_for_read(GPCMD_READ_TOC_PMA_ATIP),
154                 safe_for_read(GPCMD_REPORT_KEY),
155                 safe_for_read(GPCMD_SCAN),
156                 safe_for_read(GPCMD_GET_CONFIGURATION),
157                 safe_for_read(GPCMD_READ_FORMAT_CAPACITIES),
158                 safe_for_read(GPCMD_GET_EVENT_STATUS_NOTIFICATION),
159                 safe_for_read(GPCMD_GET_PERFORMANCE),
160                 safe_for_read(GPCMD_SEEK),
161                 safe_for_read(GPCMD_STOP_PLAY_SCAN),
162
163                 /* Basic writing commands */
164                 safe_for_write(WRITE_6),
165                 safe_for_write(WRITE_10),
166                 safe_for_write(WRITE_VERIFY),
167                 safe_for_write(WRITE_12),
168                 safe_for_write(WRITE_VERIFY_12),
169                 safe_for_write(WRITE_16),
170                 safe_for_write(WRITE_LONG),
171                 safe_for_write(WRITE_LONG_2),
172                 safe_for_write(ERASE),
173                 safe_for_write(GPCMD_MODE_SELECT_10),
174                 safe_for_write(MODE_SELECT),
175                 safe_for_write(LOG_SELECT),
176                 safe_for_write(GPCMD_BLANK),
177                 safe_for_write(GPCMD_CLOSE_TRACK),
178                 safe_for_write(GPCMD_FLUSH_CACHE),
179                 safe_for_write(GPCMD_FORMAT_UNIT),
180                 safe_for_write(GPCMD_REPAIR_RZONE_TRACK),
181                 safe_for_write(GPCMD_RESERVE_RZONE_TRACK),
182                 safe_for_write(GPCMD_SEND_DVD_STRUCTURE),
183                 safe_for_write(GPCMD_SEND_EVENT),
184                 safe_for_write(GPCMD_SEND_KEY),
185                 safe_for_write(GPCMD_SEND_OPC),
186                 safe_for_write(GPCMD_SEND_CUE_SHEET),
187                 safe_for_write(GPCMD_SET_SPEED),
188                 safe_for_write(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL),
189                 safe_for_write(GPCMD_LOAD_UNLOAD),
190                 safe_for_write(GPCMD_SET_STREAMING),
191         };
192         unsigned char type = cmd_type[cmd[0]];
193         int has_write_perm = 0;
194
195         /* Anybody who can open the device can do a read-safe command */
196         if (type & CMD_READ_SAFE)
197                 return 0;
198
199         /*
200          * file can be NULL from ioctl_by_bdev()...
201          */
202         if (file)
203                 has_write_perm = file->f_mode & FMODE_WRITE;
204
205         /* Write-safe commands just require a writable open.. */
206         if ((type & CMD_WRITE_SAFE) && has_write_perm)
207                 return 0;
208
209         /* And root can do any command.. */
210         if (capable(CAP_SYS_RAWIO))
211                 return 0;
212
213         if (!type) {
214                 cmd_type[cmd[0]] = CMD_WARNED;
215                 printk(KERN_WARNING "scsi: unknown opcode 0x%02x\n", cmd[0]);
216         }
217
218         /* Otherwise fail it with an "Operation not permitted" */
219         return -EPERM;
220 }
221
222 static int sg_io(struct file *file, request_queue_t *q,
223                 struct gendisk *bd_disk, struct sg_io_hdr *hdr)
224 {
225         unsigned long start_time;
226         int writing = 0, ret = 0;
227         struct request *rq;
228         struct bio *bio;
229         char sense[SCSI_SENSE_BUFFERSIZE];
230         unsigned char cmd[BLK_MAX_CDB];
231
232         if (hdr->interface_id != 'S')
233                 return -EINVAL;
234         if (hdr->cmd_len > BLK_MAX_CDB)
235                 return -EINVAL;
236         if (copy_from_user(cmd, hdr->cmdp, hdr->cmd_len))
237                 return -EFAULT;
238         if (verify_command(file, cmd))
239                 return -EPERM;
240
241         if (hdr->dxfer_len > (q->max_hw_sectors << 9))
242                 return -EIO;
243
244         if (hdr->dxfer_len)
245                 switch (hdr->dxfer_direction) {
246                 default:
247                         return -EINVAL;
248                 case SG_DXFER_TO_FROM_DEV:
249                 case SG_DXFER_TO_DEV:
250                         writing = 1;
251                         break;
252                 case SG_DXFER_FROM_DEV:
253                         break;
254                 }
255
256         rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
257         if (!rq)
258                 return -ENOMEM;
259
260         if (hdr->iovec_count) {
261                 const int size = sizeof(struct sg_iovec) * hdr->iovec_count;
262                 struct sg_iovec *iov;
263
264                 iov = kmalloc(size, GFP_KERNEL);
265                 if (!iov) {
266                         ret = -ENOMEM;
267                         goto out;
268                 }
269
270                 if (copy_from_user(iov, hdr->dxferp, size)) {
271                         kfree(iov);
272                         ret = -EFAULT;
273                         goto out;
274                 }
275
276                 ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count);
277                 kfree(iov);
278         } else if (hdr->dxfer_len)
279                 ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len);
280
281         if (ret)
282                 goto out;
283
284         /*
285          * fill in request structure
286          */
287         rq->cmd_len = hdr->cmd_len;
288         memcpy(rq->cmd, cmd, hdr->cmd_len);
289         if (sizeof(rq->cmd) != hdr->cmd_len)
290                 memset(rq->cmd + hdr->cmd_len, 0, sizeof(rq->cmd) - hdr->cmd_len);
291
292         memset(sense, 0, sizeof(sense));
293         rq->sense = sense;
294         rq->sense_len = 0;
295
296         rq->flags |= REQ_BLOCK_PC;
297         bio = rq->bio;
298
299         /*
300          * bounce this after holding a reference to the original bio, it's
301          * needed for proper unmapping
302          */
303         if (rq->bio)
304                 blk_queue_bounce(q, &rq->bio);
305
306         rq->timeout = (hdr->timeout * HZ) / 1000;
307         if (!rq->timeout)
308                 rq->timeout = q->sg_timeout;
309         if (!rq->timeout)
310                 rq->timeout = BLK_DEFAULT_TIMEOUT;
311
312         start_time = jiffies;
313
314         /* ignore return value. All information is passed back to caller
315          * (if he doesn't check that is his problem).
316          * N.B. a non-zero SCSI status is _not_ necessarily an error.
317          */
318         blk_execute_rq(q, bd_disk, rq, 0);
319
320         /* write to all output members */
321         hdr->status = 0xff & rq->errors;
322         hdr->masked_status = status_byte(rq->errors);
323         hdr->msg_status = msg_byte(rq->errors);
324         hdr->host_status = host_byte(rq->errors);
325         hdr->driver_status = driver_byte(rq->errors);
326         hdr->info = 0;
327         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
328                 hdr->info |= SG_INFO_CHECK;
329         hdr->resid = rq->data_len;
330         hdr->duration = ((jiffies - start_time) * 1000) / HZ;
331         hdr->sb_len_wr = 0;
332
333         if (rq->sense_len && hdr->sbp) {
334                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
335
336                 if (!copy_to_user(hdr->sbp, rq->sense, len))
337                         hdr->sb_len_wr = len;
338         }
339
340         if (blk_rq_unmap_user(bio, hdr->dxfer_len))
341                 ret = -EFAULT;
342
343         /* may not have succeeded, but output values written to control
344          * structure (struct sg_io_hdr).  */
345 out:
346         blk_put_request(rq);
347         return ret;
348 }
349
350 #define OMAX_SB_LEN 16          /* For backward compatibility */
351
352 static int sg_scsi_ioctl(struct file *file, request_queue_t *q,
353                          struct gendisk *bd_disk, Scsi_Ioctl_Command __user *sic)
354 {
355         struct request *rq;
356         int err;
357         unsigned int in_len, out_len, bytes, opcode, cmdlen;
358         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
359
360         /*
361          * get in an out lengths, verify they don't exceed a page worth of data
362          */
363         if (get_user(in_len, &sic->inlen))
364                 return -EFAULT;
365         if (get_user(out_len, &sic->outlen))
366                 return -EFAULT;
367         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
368                 return -EINVAL;
369         if (get_user(opcode, sic->data))
370                 return -EFAULT;
371
372         bytes = max(in_len, out_len);
373         if (bytes) {
374                 buffer = kmalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
375                 if (!buffer)
376                         return -ENOMEM;
377
378                 memset(buffer, 0, bytes);
379         }
380
381         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
382
383         cmdlen = COMMAND_SIZE(opcode);
384
385         /*
386          * get command and data to send to device, if any
387          */
388         err = -EFAULT;
389         rq->cmd_len = cmdlen;
390         if (copy_from_user(rq->cmd, sic->data, cmdlen))
391                 goto error;
392
393         if (copy_from_user(buffer, sic->data + cmdlen, in_len))
394                 goto error;
395
396         err = verify_command(file, rq->cmd);
397         if (err)
398                 goto error;
399
400         switch (opcode) {
401                 case SEND_DIAGNOSTIC:
402                 case FORMAT_UNIT:
403                         rq->timeout = FORMAT_UNIT_TIMEOUT;
404                         break;
405                 case START_STOP:
406                         rq->timeout = START_STOP_TIMEOUT;
407                         break;
408                 case MOVE_MEDIUM:
409                         rq->timeout = MOVE_MEDIUM_TIMEOUT;
410                         break;
411                 case READ_ELEMENT_STATUS:
412                         rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
413                         break;
414                 case READ_DEFECT_DATA:
415                         rq->timeout = READ_DEFECT_DATA_TIMEOUT;
416                         break;
417                 default:
418                         rq->timeout = BLK_DEFAULT_TIMEOUT;
419                         break;
420         }
421
422         memset(sense, 0, sizeof(sense));
423         rq->sense = sense;
424         rq->sense_len = 0;
425
426         rq->data = buffer;
427         rq->data_len = bytes;
428         rq->flags |= REQ_BLOCK_PC;
429
430         blk_execute_rq(q, bd_disk, rq, 0);
431         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
432         if (err) {
433                 if (rq->sense_len && rq->sense) {
434                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
435                                 rq->sense_len : OMAX_SB_LEN;
436                         if (copy_to_user(sic->data, rq->sense, bytes))
437                                 err = -EFAULT;
438                 }
439         } else {
440                 if (copy_to_user(sic->data, buffer, out_len))
441                         err = -EFAULT;
442         }
443         
444 error:
445         kfree(buffer);
446         blk_put_request(rq);
447         return err;
448 }
449
450
451 /* Send basic block requests */
452 static int __blk_send_generic(request_queue_t *q, struct gendisk *bd_disk, int cmd, int data)
453 {
454         struct request *rq;
455         int err;
456
457         rq = blk_get_request(q, WRITE, __GFP_WAIT);
458         rq->flags |= REQ_BLOCK_PC;
459         rq->data = NULL;
460         rq->data_len = 0;
461         rq->timeout = BLK_DEFAULT_TIMEOUT;
462         memset(rq->cmd, 0, sizeof(rq->cmd));
463         rq->cmd[0] = cmd;
464         rq->cmd[4] = data;
465         rq->cmd_len = 6;
466         err = blk_execute_rq(q, bd_disk, rq, 0);
467         blk_put_request(rq);
468
469         return err;
470 }
471
472 static inline int blk_send_start_stop(request_queue_t *q, struct gendisk *bd_disk, int data)
473 {
474         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
475 }
476
477 int scsi_cmd_ioctl(struct file *file, struct gendisk *bd_disk, unsigned int cmd, void __user *arg)
478 {
479         request_queue_t *q;
480         int err;
481
482         q = bd_disk->queue;
483         if (!q)
484                 return -ENXIO;
485
486         if (blk_get_queue(q))
487                 return -ENXIO;
488
489         switch (cmd) {
490                 /*
491                  * new sgv3 interface
492                  */
493                 case SG_GET_VERSION_NUM:
494                         err = sg_get_version(arg);
495                         break;
496                 case SCSI_IOCTL_GET_IDLUN:
497                         err = scsi_get_idlun(q, arg);
498                         break;
499                 case SCSI_IOCTL_GET_BUS_NUMBER:
500                         err = scsi_get_bus(q, arg);
501                         break;
502                 case SG_SET_TIMEOUT:
503                         err = sg_set_timeout(q, arg);
504                         break;
505                 case SG_GET_TIMEOUT:
506                         err = sg_get_timeout(q);
507                         break;
508                 case SG_GET_RESERVED_SIZE:
509                         err = sg_get_reserved_size(q, arg);
510                         break;
511                 case SG_SET_RESERVED_SIZE:
512                         err = sg_set_reserved_size(q, arg);
513                         break;
514                 case SG_EMULATED_HOST:
515                         err = sg_emulated_host(q, arg);
516                         break;
517                 case SG_IO: {
518                         struct sg_io_hdr hdr;
519
520                         err = -EFAULT;
521                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
522                                 break;
523                         err = sg_io(file, q, bd_disk, &hdr);
524                         if (err == -EFAULT)
525                                 break;
526
527                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
528                                 err = -EFAULT;
529                         break;
530                 }
531                 case CDROM_SEND_PACKET: {
532                         struct cdrom_generic_command cgc;
533                         struct sg_io_hdr hdr;
534
535                         err = -EFAULT;
536                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
537                                 break;
538                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
539                         memset(&hdr, 0, sizeof(hdr));
540                         hdr.interface_id = 'S';
541                         hdr.cmd_len = sizeof(cgc.cmd);
542                         hdr.dxfer_len = cgc.buflen;
543                         err = 0;
544                         switch (cgc.data_direction) {
545                                 case CGC_DATA_UNKNOWN:
546                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
547                                         break;
548                                 case CGC_DATA_WRITE:
549                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
550                                         break;
551                                 case CGC_DATA_READ:
552                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
553                                         break;
554                                 case CGC_DATA_NONE:
555                                         hdr.dxfer_direction = SG_DXFER_NONE;
556                                         break;
557                                 default:
558                                         err = -EINVAL;
559                         }
560                         if (err)
561                                 break;
562
563                         hdr.dxferp = cgc.buffer;
564                         hdr.sbp = cgc.sense;
565                         if (hdr.sbp)
566                                 hdr.mx_sb_len = sizeof(struct request_sense);
567                         hdr.timeout = cgc.timeout;
568                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
569                         hdr.cmd_len = sizeof(cgc.cmd);
570
571                         err = sg_io(file, q, bd_disk, &hdr);
572                         if (err == -EFAULT)
573                                 break;
574
575                         if (hdr.status)
576                                 err = -EIO;
577
578                         cgc.stat = err;
579                         cgc.buflen = hdr.resid;
580                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
581                                 err = -EFAULT;
582
583                         break;
584                 }
585
586                 /*
587                  * old junk scsi send command ioctl
588                  */
589                 case SCSI_IOCTL_SEND_COMMAND:
590                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
591                         err = -EINVAL;
592                         if (!arg)
593                                 break;
594
595                         err = sg_scsi_ioctl(file, q, bd_disk, arg);
596                         break;
597                 case CDROMCLOSETRAY:
598                         err = blk_send_start_stop(q, bd_disk, 0x03);
599                         break;
600                 case CDROMEJECT:
601                         err = blk_send_start_stop(q, bd_disk, 0x02);
602                         break;
603                 default:
604                         err = -ENOTTY;
605         }
606
607         blk_put_queue(q);
608         return err;
609 }
610
611 EXPORT_SYMBOL(scsi_cmd_ioctl);