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_DEV:
 250                         writing = 1;
 251                         break;
 252                 case SG_DXFER_TO_FROM_DEV:
 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         memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
 290         memcpy(rq->cmd, 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         rq->retries = 0;
 313
 314         start_time = jiffies;
 315
 316         /* ignore return value. All information is passed back to caller
 317          * (if he doesn't check that is his problem).
 318          * N.B. a non-zero SCSI status is _not_ necessarily an error.
 319          */
 320         blk_execute_rq(q, bd_disk, rq, 0);
 321
 322         /* write to all output members */
 323         hdr->status = 0xff & rq->errors;
 324         hdr->masked_status = status_byte(rq->errors);
 325         hdr->msg_status = msg_byte(rq->errors);
 326         hdr->host_status = host_byte(rq->errors);
 327         hdr->driver_status = driver_byte(rq->errors);
 328         hdr->info = 0;
 329         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
 330                 hdr->info |= SG_INFO_CHECK;
 331         hdr->resid = rq->data_len;
 332         hdr->duration = ((jiffies - start_time) * 1000) / HZ;
 333         hdr->sb_len_wr = 0;
 334
 335         if (rq->sense_len && hdr->sbp) {
 336                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
 337
 338                 if (!copy_to_user(hdr->sbp, rq->sense, len))
 339                         hdr->sb_len_wr = len;
 340         }
 341
 342         if (blk_rq_unmap_user(bio, hdr->dxfer_len))
 343                 ret = -EFAULT;
 344
 345         /* may not have succeeded, but output values written to control
 346          * structure (struct sg_io_hdr).  */
 347 out:
 348         blk_put_request(rq);
 349         return ret;
 350 }
 351
 352 #define OMAX_SB_LEN 16          /* For backward compatibility */
 353
 354 static int sg_scsi_ioctl(struct file *file, request_queue_t *q,
 355                          struct gendisk *bd_disk, Scsi_Ioctl_Command __user *sic)
 356 {
 357         struct request *rq;
 358         int err;
 359         unsigned int in_len, out_len, bytes, opcode, cmdlen;
 360         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
 361
 362         /*
 363          * get in an out lengths, verify they don't exceed a page worth of data
 364          */
 365         if (get_user(in_len, &sic->inlen))
 366                 return -EFAULT;
 367         if (get_user(out_len, &sic->outlen))
 368                 return -EFAULT;
 369         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
 370                 return -EINVAL;
 371         if (get_user(opcode, sic->data))
 372                 return -EFAULT;
 373
 374         bytes = max(in_len, out_len);
 375         if (bytes) {
 376                 buffer = kmalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
 377                 if (!buffer)
 378                         return -ENOMEM;
 379
 380                 memset(buffer, 0, bytes);
 381         }
 382
 383         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
 384
 385         cmdlen = COMMAND_SIZE(opcode);
 386
 387         /*
 388          * get command and data to send to device, if any
 389          */
 390         err = -EFAULT;
 391         rq->cmd_len = cmdlen;
 392         if (copy_from_user(rq->cmd, sic->data, cmdlen))
 393                 goto error;
 394
 395         if (copy_from_user(buffer, sic->data + cmdlen, in_len))
 396                 goto error;
 397
 398         err = verify_command(file, rq->cmd);
 399         if (err)
 400                 goto error;
 401
 402         switch (opcode) {
 403                 case SEND_DIAGNOSTIC:
 404                 case FORMAT_UNIT:
 405                         rq->timeout = FORMAT_UNIT_TIMEOUT;
 406                         break;
 407                 case START_STOP:
 408                         rq->timeout = START_STOP_TIMEOUT;
 409                         break;
 410                 case MOVE_MEDIUM:
 411                         rq->timeout = MOVE_MEDIUM_TIMEOUT;
 412                         break;
 413                 case READ_ELEMENT_STATUS:
 414                         rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
 415                         break;
 416                 case READ_DEFECT_DATA:
 417                         rq->timeout = READ_DEFECT_DATA_TIMEOUT;
 418                         break;
 419                 default:
 420                         rq->timeout = BLK_DEFAULT_TIMEOUT;
 421                         break;
 422         }
 423
 424         memset(sense, 0, sizeof(sense));
 425         rq->sense = sense;
 426         rq->sense_len = 0;
 427
 428         rq->data = buffer;
 429         rq->data_len = bytes;
 430         rq->flags |= REQ_BLOCK_PC;
 431         rq->retries = 0;
 432
 433         blk_execute_rq(q, bd_disk, rq, 0);
 434         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
 435         if (err) {
 436                 if (rq->sense_len && rq->sense) {
 437                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
 438                                 rq->sense_len : OMAX_SB_LEN;
 439                         if (copy_to_user(sic->data, rq->sense, bytes))
 440                                 err = -EFAULT;
 441                 }
 442         } else {
 443                 if (copy_to_user(sic->data, buffer, out_len))
 444                         err = -EFAULT;
 445         }
 446
 447 error:
 448         kfree(buffer);
 449         blk_put_request(rq);
 450         return err;
 451 }
 452
 453
 454 /* Send basic block requests */
 455 static int __blk_send_generic(request_queue_t *q, struct gendisk *bd_disk, int cmd, int data)
 456 {
 457         struct request *rq;
 458         int err;
 459
 460         rq = blk_get_request(q, WRITE, __GFP_WAIT);
 461         rq->flags |= REQ_BLOCK_PC;
 462         rq->data = NULL;
 463         rq->data_len = 0;
 464         rq->timeout = BLK_DEFAULT_TIMEOUT;
 465         memset(rq->cmd, 0, sizeof(rq->cmd));
 466         rq->cmd[0] = cmd;
 467         rq->cmd[4] = data;
 468         rq->cmd_len = 6;
 469         err = blk_execute_rq(q, bd_disk, rq, 0);
 470         blk_put_request(rq);
 471
 472         return err;
 473 }
 474
 475 static inline int blk_send_start_stop(request_queue_t *q, struct gendisk *bd_disk, int data)
 476 {
 477         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
 478 }
 479
 480 int scsi_cmd_ioctl(struct file *file, struct gendisk *bd_disk, unsigned int cmd, void __user *arg)
 481 {
 482         request_queue_t *q;
 483         int err;
 484
 485         q = bd_disk->queue;
 486         if (!q)
 487                 return -ENXIO;
 488
 489         if (blk_get_queue(q))
 490                 return -ENXIO;
 491
 492         switch (cmd) {
 493                 /*
 494                  * new sgv3 interface
 495                  */
 496                 case SG_GET_VERSION_NUM:
 497                         err = sg_get_version(arg);
 498                         break;
 499                 case SCSI_IOCTL_GET_IDLUN:
 500                         err = scsi_get_idlun(q, arg);
 501                         break;
 502                 case SCSI_IOCTL_GET_BUS_NUMBER:
 503                         err = scsi_get_bus(q, arg);
 504                         break;
 505                 case SG_SET_TIMEOUT:
 506                         err = sg_set_timeout(q, arg);
 507                         break;
 508                 case SG_GET_TIMEOUT:
 509                         err = sg_get_timeout(q);
 510                         break;
 511                 case SG_GET_RESERVED_SIZE:
 512                         err = sg_get_reserved_size(q, arg);
 513                         break;
 514                 case SG_SET_RESERVED_SIZE:
 515                         err = sg_set_reserved_size(q, arg);
 516                         break;
 517                 case SG_EMULATED_HOST:
 518                         err = sg_emulated_host(q, arg);
 519                         break;
 520                 case SG_IO: {
 521                         struct sg_io_hdr hdr;
 522
 523                         err = -EFAULT;
 524                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
 525                                 break;
 526                         err = sg_io(file, q, bd_disk, &hdr);
 527                         if (err == -EFAULT)
 528                                 break;
 529
 530                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
 531                                 err = -EFAULT;
 532                         break;
 533                 }
 534                 case CDROM_SEND_PACKET: {
 535                         struct cdrom_generic_command cgc;
 536                         struct sg_io_hdr hdr;
 537
 538                         err = -EFAULT;
 539                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
 540                                 break;
 541                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
 542                         memset(&hdr, 0, sizeof(hdr));
 543                         hdr.interface_id = 'S';
 544                         hdr.cmd_len = sizeof(cgc.cmd);
 545                         hdr.dxfer_len = cgc.buflen;
 546                         err = 0;
 547                         switch (cgc.data_direction) {
 548                                 case CGC_DATA_UNKNOWN:
 549                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
 550                                         break;
 551                                 case CGC_DATA_WRITE:
 552                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
 553                                         break;
 554                                 case CGC_DATA_READ:
 555                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
 556                                         break;
 557                                 case CGC_DATA_NONE:
 558                                         hdr.dxfer_direction = SG_DXFER_NONE;
 559                                         break;
 560                                 default:
 561                                         err = -EINVAL;
 562                         }
 563                         if (err)
 564                                 break;
 565
 566                         hdr.dxferp = cgc.buffer;
 567                         hdr.sbp = cgc.sense;
 568                         if (hdr.sbp)
 569                                 hdr.mx_sb_len = sizeof(struct request_sense);
 570                         hdr.timeout = cgc.timeout;
 571                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
 572                         hdr.cmd_len = sizeof(cgc.cmd);
 573
 574                         err = sg_io(file, q, bd_disk, &hdr);
 575                         if (err == -EFAULT)
 576                                 break;
 577
 578                         if (hdr.status)
 579                                 err = -EIO;
 580
 581                         cgc.stat = err;
 582                         cgc.buflen = hdr.resid;
 583                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
 584                                 err = -EFAULT;
 585
 586                         break;
 587                 }
 588
 589                 /*
 590                  * old junk scsi send command ioctl
 591                  */
 592                 case SCSI_IOCTL_SEND_COMMAND:
 593                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
 594                         err = -EINVAL;
 595                         if (!arg)
 596                                 break;
 597
 598                         err = sg_scsi_ioctl(file, q, bd_disk, arg);
 599                         break;
 600                 case CDROMCLOSETRAY:
 601                         err = blk_send_start_stop(q, bd_disk, 0x03);
 602                         break;
 603                 case CDROMEJECT:
 604                         err = blk_send_start_stop(q, bd_disk, 0x02);
 605                         break;
 606                 default:
 607                         err = -ENOTTY;
 608         }
 609
 610         blk_put_queue(q);
 611         return err;
 612 }
 613
 614 EXPORT_SYMBOL(scsi_cmd_ioctl);