drivers/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 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 safe_for_read(cmd)      [cmd] = CMD_READ_SAFE
 111 #define safe_for_write(cmd)     [cmd] = CMD_WRITE_SAFE
 112
 113 static int verify_command(struct file *file, unsigned char *cmd)
 114 {
 115         static const unsigned char cmd_type[256] = {
 116
 117                 /* Basic read-only commands */
 118                 safe_for_read(TEST_UNIT_READY),
 119                 safe_for_read(REQUEST_SENSE),
 120                 safe_for_read(READ_6),
 121                 safe_for_read(READ_10),
 122                 safe_for_read(READ_12),
 123                 safe_for_read(READ_16),
 124                 safe_for_read(READ_BUFFER),
 125                 safe_for_read(READ_LONG),
 126                 safe_for_read(INQUIRY),
 127                 safe_for_read(MODE_SENSE),
 128                 safe_for_read(MODE_SENSE_10),
 129                 safe_for_read(START_STOP),
 130
 131                 /* Audio CD commands */
 132                 safe_for_read(GPCMD_PLAY_CD),
 133                 safe_for_read(GPCMD_PLAY_AUDIO_10),
 134                 safe_for_read(GPCMD_PLAY_AUDIO_MSF),
 135                 safe_for_read(GPCMD_PLAY_AUDIO_TI),
 136
 137                 /* CD/DVD data reading */
 138                 safe_for_read(GPCMD_READ_CD),
 139                 safe_for_read(GPCMD_READ_CD_MSF),
 140                 safe_for_read(GPCMD_READ_DISC_INFO),
 141                 safe_for_read(GPCMD_READ_CDVD_CAPACITY),
 142                 safe_for_read(GPCMD_READ_DVD_STRUCTURE),
 143                 safe_for_read(GPCMD_READ_HEADER),
 144                 safe_for_read(GPCMD_READ_TRACK_RZONE_INFO),
 145                 safe_for_read(GPCMD_READ_SUBCHANNEL),
 146                 safe_for_read(GPCMD_READ_TOC_PMA_ATIP),
 147                 safe_for_read(GPCMD_REPORT_KEY),
 148                 safe_for_read(GPCMD_SCAN),
 149
 150                 /* Basic writing commands */
 151                 safe_for_write(WRITE_6),
 152                 safe_for_write(WRITE_10),
 153                 safe_for_write(WRITE_VERIFY),
 154                 safe_for_write(WRITE_12),
 155                 safe_for_write(WRITE_VERIFY_12),
 156                 safe_for_write(WRITE_16),
 157                 safe_for_write(WRITE_BUFFER),
 158                 safe_for_write(WRITE_LONG),
 159         };
 160         unsigned char type = cmd_type[cmd[0]];
 161
 162         /* Anybody who can open the device can do a read-safe command */
 163         if (type & CMD_READ_SAFE)
 164                 return 0;
 165
 166         /* Write-safe commands just require a writable open.. */
 167         if (type & CMD_WRITE_SAFE) {
 168                 if (file->f_mode & FMODE_WRITE)
 169                         return 0;
 170         }
 171
 172         /* And root can do any command.. */
 173         if (capable(CAP_SYS_RAWIO))
 174                 return 0;
 175
 176         /* Otherwise fail it with an "Operation not permitted" */
 177         return -EPERM;
 178 }
 179
 180 static int sg_io(struct file *file, request_queue_t *q,
 181                 struct gendisk *bd_disk, struct sg_io_hdr *hdr)
 182 {
 183         unsigned long start_time;
 184         int reading, writing;
 185         struct request *rq;
 186         struct bio *bio;
 187         char sense[SCSI_SENSE_BUFFERSIZE];
 188         unsigned char cmd[BLK_MAX_CDB];
 189
 190         if (hdr->interface_id != 'S')
 191                 return -EINVAL;
 192         if (hdr->cmd_len > BLK_MAX_CDB)
 193                 return -EINVAL;
 194         if (copy_from_user(cmd, hdr->cmdp, hdr->cmd_len))
 195                 return -EFAULT;
 196         if (verify_command(file, cmd))
 197                 return -EPERM;
 198
 199         /*
 200          * we'll do that later
 201          */
 202         if (hdr->iovec_count)
 203                 return -EOPNOTSUPP;
 204
 205         if (hdr->dxfer_len > (q->max_sectors << 9))
 206                 return -EIO;
 207
 208         reading = writing = 0;
 209         if (hdr->dxfer_len) {
 210                 switch (hdr->dxfer_direction) {
 211                 default:
 212                         return -EINVAL;
 213                 case SG_DXFER_TO_FROM_DEV:
 214                         reading = 1;
 215                         /* fall through */
 216                 case SG_DXFER_TO_DEV:
 217                         writing = 1;
 218                         break;
 219                 case SG_DXFER_FROM_DEV:
 220                         reading = 1;
 221                         break;
 222                 }
 223
 224                 rq = blk_rq_map_user(q, writing ? WRITE : READ, hdr->dxferp,
 225                                      hdr->dxfer_len);
 226
 227                 if (IS_ERR(rq))
 228                         return PTR_ERR(rq);
 229         } else
 230                 rq = blk_get_request(q, READ, __GFP_WAIT);
 231
 232         /*
 233          * fill in request structure
 234          */
 235         rq->cmd_len = hdr->cmd_len;
 236         memcpy(rq->cmd, cmd, hdr->cmd_len);
 237         if (sizeof(rq->cmd) != hdr->cmd_len)
 238                 memset(rq->cmd + hdr->cmd_len, 0, sizeof(rq->cmd) - hdr->cmd_len);
 239
 240         memset(sense, 0, sizeof(sense));
 241         rq->sense = sense;
 242         rq->sense_len = 0;
 243
 244         rq->flags |= REQ_BLOCK_PC;
 245         bio = rq->bio;
 246
 247         /*
 248          * bounce this after holding a reference to the original bio, it's
 249          * needed for proper unmapping
 250          */
 251         if (rq->bio)
 252                 blk_queue_bounce(q, &rq->bio);
 253
 254         rq->timeout = (hdr->timeout * HZ) / 1000;
 255         if (!rq->timeout)
 256                 rq->timeout = q->sg_timeout;
 257         if (!rq->timeout)
 258                 rq->timeout = BLK_DEFAULT_TIMEOUT;
 259
 260         start_time = jiffies;
 261
 262         /* ignore return value. All information is passed back to caller
 263          * (if he doesn't check that is his problem).
 264          * N.B. a non-zero SCSI status is _not_ necessarily an error.
 265          */
 266         blk_execute_rq(q, bd_disk, rq);
 267
 268         /* write to all output members */
 269         hdr->status = rq->errors;
 270         hdr->masked_status = (hdr->status >> 1) & 0x1f;
 271         hdr->msg_status = 0;
 272         hdr->host_status = 0;
 273         hdr->driver_status = 0;
 274         hdr->info = 0;
 275         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
 276                 hdr->info |= SG_INFO_CHECK;
 277         hdr->resid = rq->data_len;
 278         hdr->duration = ((jiffies - start_time) * 1000) / HZ;
 279         hdr->sb_len_wr = 0;
 280
 281         if (rq->sense_len && hdr->sbp) {
 282                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
 283
 284                 if (!copy_to_user(hdr->sbp, rq->sense, len))
 285                         hdr->sb_len_wr = len;
 286         }
 287
 288         if (blk_rq_unmap_user(rq, bio, hdr->dxfer_len))
 289                 return -EFAULT;
 290
 291         /* may not have succeeded, but output values written to control
 292          * structure (struct sg_io_hdr).  */
 293         return 0;
 294 }
 295
 296 #define FORMAT_UNIT_TIMEOUT             (2 * 60 * 60 * HZ)
 297 #define START_STOP_TIMEOUT              (60 * HZ)
 298 #define MOVE_MEDIUM_TIMEOUT             (5 * 60 * HZ)
 299 #define READ_ELEMENT_STATUS_TIMEOUT     (5 * 60 * HZ)
 300 #define READ_DEFECT_DATA_TIMEOUT        (60 * HZ )
 301 #define OMAX_SB_LEN 16          /* For backward compatibility */
 302
 303 static int sg_scsi_ioctl(struct file *file, request_queue_t *q,
 304                          struct gendisk *bd_disk, Scsi_Ioctl_Command __user *sic)
 305 {
 306         struct request *rq;
 307         int err, in_len, out_len, bytes, opcode, cmdlen;
 308         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
 309
 310         /*
 311          * get in an out lengths, verify they don't exceed a page worth of data
 312          */
 313         if (get_user(in_len, &sic->inlen))
 314                 return -EFAULT;
 315         if (get_user(out_len, &sic->outlen))
 316                 return -EFAULT;
 317         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
 318                 return -EINVAL;
 319         if (get_user(opcode, sic->data))
 320                 return -EFAULT;
 321
 322         bytes = max(in_len, out_len);
 323         if (bytes) {
 324                 buffer = kmalloc(bytes, q->bounce_gfp | GFP_USER);
 325                 if (!buffer)
 326                         return -ENOMEM;
 327
 328                 memset(buffer, 0, bytes);
 329         }
 330
 331         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
 332
 333         cmdlen = COMMAND_SIZE(opcode);
 334
 335         /*
 336          * get command and data to send to device, if any
 337          */
 338         err = -EFAULT;
 339         rq->cmd_len = cmdlen;
 340         if (copy_from_user(rq->cmd, sic->data, cmdlen))
 341                 goto error;
 342
 343         if (copy_from_user(buffer, sic->data + cmdlen, in_len))
 344                 goto error;
 345
 346         err = verify_command(file, rq->cmd);
 347         if (err)
 348                 goto error;
 349
 350         switch (opcode) {
 351                 case SEND_DIAGNOSTIC:
 352                 case FORMAT_UNIT:
 353                         rq->timeout = FORMAT_UNIT_TIMEOUT;
 354                         break;
 355                 case START_STOP:
 356                         rq->timeout = START_STOP_TIMEOUT;
 357                         break;
 358                 case MOVE_MEDIUM:
 359                         rq->timeout = MOVE_MEDIUM_TIMEOUT;
 360                         break;
 361                 case READ_ELEMENT_STATUS:
 362                         rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
 363                         break;
 364                 case READ_DEFECT_DATA:
 365                         rq->timeout = READ_DEFECT_DATA_TIMEOUT;
 366                         break;
 367                 default:
 368                         rq->timeout = BLK_DEFAULT_TIMEOUT;
 369                         break;
 370         }
 371
 372         memset(sense, 0, sizeof(sense));
 373         rq->sense = sense;
 374         rq->sense_len = 0;
 375
 376         rq->data = buffer;
 377         rq->data_len = bytes;
 378         rq->flags |= REQ_BLOCK_PC;
 379
 380         blk_execute_rq(q, bd_disk, rq);
 381         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
 382         if (err) {
 383                 if (rq->sense_len && rq->sense) {
 384                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
 385                                 rq->sense_len : OMAX_SB_LEN;
 386                         if (copy_to_user(sic->data, rq->sense, bytes))
 387                                 err = -EFAULT;
 388                 }
 389         } else {
 390                 if (copy_to_user(sic->data, buffer, out_len))
 391                         err = -EFAULT;
 392         }
 393
 394 error:
 395         kfree(buffer);
 396         blk_put_request(rq);
 397         return err;
 398 }
 399
 400 int scsi_cmd_ioctl(struct file *file, struct gendisk *bd_disk, unsigned int cmd, void __user *arg)
 401 {
 402         request_queue_t *q;
 403         struct request *rq;
 404         int close = 0, err;
 405
 406         q = bd_disk->queue;
 407         if (!q)
 408                 return -ENXIO;
 409
 410         if (blk_get_queue(q))
 411                 return -ENXIO;
 412
 413         switch (cmd) {
 414                 /*
 415                  * new sgv3 interface
 416                  */
 417                 case SG_GET_VERSION_NUM:
 418                         err = sg_get_version(arg);
 419                         break;
 420                 case SCSI_IOCTL_GET_IDLUN:
 421                         err = scsi_get_idlun(q, arg);
 422                         break;
 423                 case SCSI_IOCTL_GET_BUS_NUMBER:
 424                         err = scsi_get_bus(q, arg);
 425                         break;
 426                 case SG_SET_TIMEOUT:
 427                         err = sg_set_timeout(q, arg);
 428                         break;
 429                 case SG_GET_TIMEOUT:
 430                         err = sg_get_timeout(q);
 431                         break;
 432                 case SG_GET_RESERVED_SIZE:
 433                         err = sg_get_reserved_size(q, arg);
 434                         break;
 435                 case SG_SET_RESERVED_SIZE:
 436                         err = sg_set_reserved_size(q, arg);
 437                         break;
 438                 case SG_EMULATED_HOST:
 439                         err = sg_emulated_host(q, arg);
 440                         break;
 441                 case SG_IO: {
 442                         struct sg_io_hdr hdr;
 443
 444                         err = -EFAULT;
 445                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
 446                                 break;
 447                         err = sg_io(file, q, bd_disk, &hdr);
 448                         if (err == -EFAULT)
 449                                 break;
 450
 451                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
 452                                 err = -EFAULT;
 453                         break;
 454                 }
 455                 case CDROM_SEND_PACKET: {
 456                         struct cdrom_generic_command cgc;
 457                         struct sg_io_hdr hdr;
 458
 459                         err = -EFAULT;
 460                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
 461                                 break;
 462                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
 463                         memset(&hdr, 0, sizeof(hdr));
 464                         hdr.interface_id = 'S';
 465                         hdr.cmd_len = sizeof(cgc.cmd);
 466                         hdr.dxfer_len = cgc.buflen;
 467                         err = 0;
 468                         switch (cgc.data_direction) {
 469                                 case CGC_DATA_UNKNOWN:
 470                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
 471                                         break;
 472                                 case CGC_DATA_WRITE:
 473                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
 474                                         break;
 475                                 case CGC_DATA_READ:
 476                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
 477                                         break;
 478                                 case CGC_DATA_NONE:
 479                                         hdr.dxfer_direction = SG_DXFER_NONE;
 480                                         break;
 481                                 default:
 482                                         err = -EINVAL;
 483                         }
 484                         if (err)
 485                                 break;
 486
 487                         hdr.dxferp = cgc.buffer;
 488                         hdr.sbp = cgc.sense;
 489                         if (hdr.sbp)
 490                                 hdr.mx_sb_len = sizeof(struct request_sense);
 491                         hdr.timeout = cgc.timeout;
 492                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
 493                         hdr.cmd_len = sizeof(cgc.cmd);
 494
 495                         err = sg_io(file, q, bd_disk, &hdr);
 496                         if (err == -EFAULT)
 497                                 break;
 498
 499                         if (hdr.status)
 500                                 err = -EIO;
 501
 502                         cgc.stat = err;
 503                         cgc.buflen = hdr.resid;
 504                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
 505                                 err = -EFAULT;
 506
 507                         break;
 508                 }
 509
 510                 /*
 511                  * old junk scsi send command ioctl
 512                  */
 513                 case SCSI_IOCTL_SEND_COMMAND:
 514                         err = -EINVAL;
 515                         if (!arg)
 516                                 break;
 517
 518                         err = sg_scsi_ioctl(file, q, bd_disk, arg);
 519                         break;
 520                 case CDROMCLOSETRAY:
 521                         close = 1;
 522                 case CDROMEJECT:
 523                         rq = blk_get_request(q, WRITE, __GFP_WAIT);
 524                         rq->flags |= REQ_BLOCK_PC;
 525                         rq->data = NULL;
 526                         rq->data_len = 0;
 527                         rq->timeout = BLK_DEFAULT_TIMEOUT;
 528                         memset(rq->cmd, 0, sizeof(rq->cmd));
 529                         rq->cmd[0] = GPCMD_START_STOP_UNIT;
 530                         rq->cmd[4] = 0x02 + (close != 0);
 531                         rq->cmd_len = 6;
 532                         err = blk_execute_rq(q, bd_disk, rq);
 533                         blk_put_request(rq);
 534                         break;
 535                 default:
 536                         err = -ENOTTY;
 537         }
 538
 539         blk_put_queue(q);
 540         return err;
 541 }
 542
 543 EXPORT_SYMBOL(scsi_cmd_ioctl);