[BLOCK] mark some block/ variables cons
[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
194         /* Anybody who can open the device can do a read-safe command */
195         if (type & CMD_READ_SAFE)
196                 return 0;
197
198         /* Write-safe commands just require a writable open.. */
199         if (type & CMD_WRITE_SAFE) {
200                 if (file->f_mode & FMODE_WRITE)
201                         return 0;
202         }
203
204         /* And root can do any command.. */
205         if (capable(CAP_SYS_RAWIO))
206                 return 0;
207
208         if (!type) {
209                 cmd_type[cmd[0]] = CMD_WARNED;
210                 printk(KERN_WARNING "scsi: unknown opcode 0x%02x\n", cmd[0]);
211         }
212
213         /* Otherwise fail it with an "Operation not permitted" */
214         return -EPERM;
215 }
216
217 static int sg_io(struct file *file, request_queue_t *q,
218                 struct gendisk *bd_disk, struct sg_io_hdr *hdr)
219 {
220         unsigned long start_time;
221         int writing = 0, ret = 0;
222         struct request *rq;
223         struct bio *bio;
224         char sense[SCSI_SENSE_BUFFERSIZE];
225         unsigned char cmd[BLK_MAX_CDB];
226
227         if (hdr->interface_id != 'S')
228                 return -EINVAL;
229         if (hdr->cmd_len > BLK_MAX_CDB)
230                 return -EINVAL;
231         if (copy_from_user(cmd, hdr->cmdp, hdr->cmd_len))
232                 return -EFAULT;
233         if (verify_command(file, cmd))
234                 return -EPERM;
235
236         if (hdr->dxfer_len > (q->max_hw_sectors << 9))
237                 return -EIO;
238
239         if (hdr->dxfer_len)
240                 switch (hdr->dxfer_direction) {
241                 default:
242                         return -EINVAL;
243                 case SG_DXFER_TO_FROM_DEV:
244                 case SG_DXFER_TO_DEV:
245                         writing = 1;
246                         break;
247                 case SG_DXFER_FROM_DEV:
248                         break;
249                 }
250
251         rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
252         if (!rq)
253                 return -ENOMEM;
254
255         if (hdr->iovec_count) {
256                 const int size = sizeof(struct sg_iovec) * hdr->iovec_count;
257                 struct sg_iovec *iov;
258
259                 iov = kmalloc(size, GFP_KERNEL);
260                 if (!iov) {
261                         ret = -ENOMEM;
262                         goto out;
263                 }
264
265                 if (copy_from_user(iov, hdr->dxferp, size)) {
266                         kfree(iov);
267                         ret = -EFAULT;
268                         goto out;
269                 }
270
271                 ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count);
272                 kfree(iov);
273         } else if (hdr->dxfer_len)
274                 ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len);
275
276         if (ret)
277                 goto out;
278
279         /*
280          * fill in request structure
281          */
282         rq->cmd_len = hdr->cmd_len;
283         memcpy(rq->cmd, cmd, hdr->cmd_len);
284         if (sizeof(rq->cmd) != hdr->cmd_len)
285                 memset(rq->cmd + hdr->cmd_len, 0, sizeof(rq->cmd) - hdr->cmd_len);
286
287         memset(sense, 0, sizeof(sense));
288         rq->sense = sense;
289         rq->sense_len = 0;
290
291         rq->flags |= REQ_BLOCK_PC;
292         bio = rq->bio;
293
294         /*
295          * bounce this after holding a reference to the original bio, it's
296          * needed for proper unmapping
297          */
298         if (rq->bio)
299                 blk_queue_bounce(q, &rq->bio);
300
301         rq->timeout = (hdr->timeout * HZ) / 1000;
302         if (!rq->timeout)
303                 rq->timeout = q->sg_timeout;
304         if (!rq->timeout)
305                 rq->timeout = BLK_DEFAULT_TIMEOUT;
306
307         start_time = jiffies;
308
309         /* ignore return value. All information is passed back to caller
310          * (if he doesn't check that is his problem).
311          * N.B. a non-zero SCSI status is _not_ necessarily an error.
312          */
313         blk_execute_rq(q, bd_disk, rq, 0);
314
315         /* write to all output members */
316         hdr->status = 0xff & rq->errors;
317         hdr->masked_status = status_byte(rq->errors);
318         hdr->msg_status = msg_byte(rq->errors);
319         hdr->host_status = host_byte(rq->errors);
320         hdr->driver_status = driver_byte(rq->errors);
321         hdr->info = 0;
322         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
323                 hdr->info |= SG_INFO_CHECK;
324         hdr->resid = rq->data_len;
325         hdr->duration = ((jiffies - start_time) * 1000) / HZ;
326         hdr->sb_len_wr = 0;
327
328         if (rq->sense_len && hdr->sbp) {
329                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
330
331                 if (!copy_to_user(hdr->sbp, rq->sense, len))
332                         hdr->sb_len_wr = len;
333         }
334
335         if (blk_rq_unmap_user(bio, hdr->dxfer_len))
336                 ret = -EFAULT;
337
338         /* may not have succeeded, but output values written to control
339          * structure (struct sg_io_hdr).  */
340 out:
341         blk_put_request(rq);
342         return ret;
343 }
344
345 #define OMAX_SB_LEN 16          /* For backward compatibility */
346
347 static int sg_scsi_ioctl(struct file *file, request_queue_t *q,
348                          struct gendisk *bd_disk, Scsi_Ioctl_Command __user *sic)
349 {
350         struct request *rq;
351         int err;
352         unsigned int in_len, out_len, bytes, opcode, cmdlen;
353         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
354
355         /*
356          * get in an out lengths, verify they don't exceed a page worth of data
357          */
358         if (get_user(in_len, &sic->inlen))
359                 return -EFAULT;
360         if (get_user(out_len, &sic->outlen))
361                 return -EFAULT;
362         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
363                 return -EINVAL;
364         if (get_user(opcode, sic->data))
365                 return -EFAULT;
366
367         bytes = max(in_len, out_len);
368         if (bytes) {
369                 buffer = kmalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
370                 if (!buffer)
371                         return -ENOMEM;
372
373                 memset(buffer, 0, bytes);
374         }
375
376         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
377
378         cmdlen = COMMAND_SIZE(opcode);
379
380         /*
381          * get command and data to send to device, if any
382          */
383         err = -EFAULT;
384         rq->cmd_len = cmdlen;
385         if (copy_from_user(rq->cmd, sic->data, cmdlen))
386                 goto error;
387
388         if (copy_from_user(buffer, sic->data + cmdlen, in_len))
389                 goto error;
390
391         err = verify_command(file, rq->cmd);
392         if (err)
393                 goto error;
394
395         switch (opcode) {
396                 case SEND_DIAGNOSTIC:
397                 case FORMAT_UNIT:
398                         rq->timeout = FORMAT_UNIT_TIMEOUT;
399                         break;
400                 case START_STOP:
401                         rq->timeout = START_STOP_TIMEOUT;
402                         break;
403                 case MOVE_MEDIUM:
404                         rq->timeout = MOVE_MEDIUM_TIMEOUT;
405                         break;
406                 case READ_ELEMENT_STATUS:
407                         rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
408                         break;
409                 case READ_DEFECT_DATA:
410                         rq->timeout = READ_DEFECT_DATA_TIMEOUT;
411                         break;
412                 default:
413                         rq->timeout = BLK_DEFAULT_TIMEOUT;
414                         break;
415         }
416
417         memset(sense, 0, sizeof(sense));
418         rq->sense = sense;
419         rq->sense_len = 0;
420
421         rq->data = buffer;
422         rq->data_len = bytes;
423         rq->flags |= REQ_BLOCK_PC;
424
425         blk_execute_rq(q, bd_disk, rq, 0);
426         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
427         if (err) {
428                 if (rq->sense_len && rq->sense) {
429                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
430                                 rq->sense_len : OMAX_SB_LEN;
431                         if (copy_to_user(sic->data, rq->sense, bytes))
432                                 err = -EFAULT;
433                 }
434         } else {
435                 if (copy_to_user(sic->data, buffer, out_len))
436                         err = -EFAULT;
437         }
438         
439 error:
440         kfree(buffer);
441         blk_put_request(rq);
442         return err;
443 }
444
445
446 /* Send basic block requests */
447 static int __blk_send_generic(request_queue_t *q, struct gendisk *bd_disk, int cmd, int data)
448 {
449         struct request *rq;
450         int err;
451
452         rq = blk_get_request(q, WRITE, __GFP_WAIT);
453         rq->flags |= REQ_BLOCK_PC;
454         rq->data = NULL;
455         rq->data_len = 0;
456         rq->timeout = BLK_DEFAULT_TIMEOUT;
457         memset(rq->cmd, 0, sizeof(rq->cmd));
458         rq->cmd[0] = cmd;
459         rq->cmd[4] = data;
460         rq->cmd_len = 6;
461         err = blk_execute_rq(q, bd_disk, rq, 0);
462         blk_put_request(rq);
463
464         return err;
465 }
466
467 static inline int blk_send_start_stop(request_queue_t *q, struct gendisk *bd_disk, int data)
468 {
469         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
470 }
471
472 int scsi_cmd_ioctl(struct file *file, struct gendisk *bd_disk, unsigned int cmd, void __user *arg)
473 {
474         request_queue_t *q;
475         int err;
476
477         q = bd_disk->queue;
478         if (!q)
479                 return -ENXIO;
480
481         if (blk_get_queue(q))
482                 return -ENXIO;
483
484         switch (cmd) {
485                 /*
486                  * new sgv3 interface
487                  */
488                 case SG_GET_VERSION_NUM:
489                         err = sg_get_version(arg);
490                         break;
491                 case SCSI_IOCTL_GET_IDLUN:
492                         err = scsi_get_idlun(q, arg);
493                         break;
494                 case SCSI_IOCTL_GET_BUS_NUMBER:
495                         err = scsi_get_bus(q, arg);
496                         break;
497                 case SG_SET_TIMEOUT:
498                         err = sg_set_timeout(q, arg);
499                         break;
500                 case SG_GET_TIMEOUT:
501                         err = sg_get_timeout(q);
502                         break;
503                 case SG_GET_RESERVED_SIZE:
504                         err = sg_get_reserved_size(q, arg);
505                         break;
506                 case SG_SET_RESERVED_SIZE:
507                         err = sg_set_reserved_size(q, arg);
508                         break;
509                 case SG_EMULATED_HOST:
510                         err = sg_emulated_host(q, arg);
511                         break;
512                 case SG_IO: {
513                         struct sg_io_hdr hdr;
514
515                         err = -EFAULT;
516                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
517                                 break;
518                         err = sg_io(file, q, bd_disk, &hdr);
519                         if (err == -EFAULT)
520                                 break;
521
522                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
523                                 err = -EFAULT;
524                         break;
525                 }
526                 case CDROM_SEND_PACKET: {
527                         struct cdrom_generic_command cgc;
528                         struct sg_io_hdr hdr;
529
530                         err = -EFAULT;
531                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
532                                 break;
533                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
534                         memset(&hdr, 0, sizeof(hdr));
535                         hdr.interface_id = 'S';
536                         hdr.cmd_len = sizeof(cgc.cmd);
537                         hdr.dxfer_len = cgc.buflen;
538                         err = 0;
539                         switch (cgc.data_direction) {
540                                 case CGC_DATA_UNKNOWN:
541                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
542                                         break;
543                                 case CGC_DATA_WRITE:
544                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
545                                         break;
546                                 case CGC_DATA_READ:
547                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
548                                         break;
549                                 case CGC_DATA_NONE:
550                                         hdr.dxfer_direction = SG_DXFER_NONE;
551                                         break;
552                                 default:
553                                         err = -EINVAL;
554                         }
555                         if (err)
556                                 break;
557
558                         hdr.dxferp = cgc.buffer;
559                         hdr.sbp = cgc.sense;
560                         if (hdr.sbp)
561                                 hdr.mx_sb_len = sizeof(struct request_sense);
562                         hdr.timeout = cgc.timeout;
563                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
564                         hdr.cmd_len = sizeof(cgc.cmd);
565
566                         err = sg_io(file, q, bd_disk, &hdr);
567                         if (err == -EFAULT)
568                                 break;
569
570                         if (hdr.status)
571                                 err = -EIO;
572
573                         cgc.stat = err;
574                         cgc.buflen = hdr.resid;
575                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
576                                 err = -EFAULT;
577
578                         break;
579                 }
580
581                 /*
582                  * old junk scsi send command ioctl
583                  */
584                 case SCSI_IOCTL_SEND_COMMAND:
585                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
586                         err = -EINVAL;
587                         if (!arg)
588                                 break;
589
590                         err = sg_scsi_ioctl(file, q, bd_disk, arg);
591                         break;
592                 case CDROMCLOSETRAY:
593                         err = blk_send_start_stop(q, bd_disk, 0x03);
594                         break;
595                 case CDROMEJECT:
596                         err = blk_send_start_stop(q, bd_disk, 0x02);
597                         break;
598                 default:
599                         err = -ENOTTY;
600         }
601
602         blk_put_queue(q);
603         return err;
604 }
605
606 EXPORT_SYMBOL(scsi_cmd_ioctl);