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