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/ratelimit.h>
  28 #include <linux/slab.h>
  29 #include <linux/times.h>
  30 #include <linux/uio.h>
  31 #include <asm/uaccess.h>
  32
  33 #include <scsi/scsi.h>
  34 #include <scsi/scsi_ioctl.h>
  35 #include <scsi/scsi_cmnd.h>
  36
  37 struct blk_cmd_filter {
  38         unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
  39         unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
  40 };
  41
  42 static struct blk_cmd_filter blk_default_cmd_filter;
  43
  44 /* Command group 3 is reserved and should never be used.  */
  45 const unsigned char scsi_command_size_tbl[8] =
  46 {
  47         6, 10, 10, 12,
  48         16, 12, 10, 10
  49 };
  50 EXPORT_SYMBOL(scsi_command_size_tbl);
  51
  52 #include <scsi/sg.h>
  53
  54 static int sg_get_version(int __user *p)
  55 {
  56         static const int sg_version_num = 30527;
  57         return put_user(sg_version_num, p);
  58 }
  59
  60 static int scsi_get_idlun(struct request_queue *q, int __user *p)
  61 {
  62         return put_user(0, p);
  63 }
  64
  65 static int scsi_get_bus(struct request_queue *q, int __user *p)
  66 {
  67         return put_user(0, p);
  68 }
  69
  70 static int sg_get_timeout(struct request_queue *q)
  71 {
  72         return jiffies_to_clock_t(q->sg_timeout);
  73 }
  74
  75 static int sg_set_timeout(struct request_queue *q, int __user *p)
  76 {
  77         int timeout, err = get_user(timeout, p);
  78
  79         if (!err)
  80                 q->sg_timeout = clock_t_to_jiffies(timeout);
  81
  82         return err;
  83 }
  84
  85 static int sg_get_reserved_size(struct request_queue *q, int __user *p)
  86 {
  87         unsigned val = min(q->sg_reserved_size, queue_max_sectors(q) << 9);
  88
  89         return put_user(val, p);
  90 }
  91
  92 static int sg_set_reserved_size(struct request_queue *q, int __user *p)
  93 {
  94         int size, err = get_user(size, p);
  95
  96         if (err)
  97                 return err;
  98
  99         if (size < 0)
 100                 return -EINVAL;
 101         if (size > (queue_max_sectors(q) << 9))
 102                 size = queue_max_sectors(q) << 9;
 103
 104         q->sg_reserved_size = size;
 105         return 0;
 106 }
 107
 108 /*
 109  * will always return that we are ATAPI even for a real SCSI drive, I'm not
 110  * so sure this is worth doing anything about (why would you care??)
 111  */
 112 static int sg_emulated_host(struct request_queue *q, int __user *p)
 113 {
 114         return put_user(1, p);
 115 }
 116
 117 static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
 118 {
 119         /* Basic read-only commands */
 120         __set_bit(TEST_UNIT_READY, filter->read_ok);
 121         __set_bit(REQUEST_SENSE, filter->read_ok);
 122         __set_bit(READ_6, filter->read_ok);
 123         __set_bit(READ_10, filter->read_ok);
 124         __set_bit(READ_12, filter->read_ok);
 125         __set_bit(READ_16, filter->read_ok);
 126         __set_bit(READ_BUFFER, filter->read_ok);
 127         __set_bit(READ_DEFECT_DATA, filter->read_ok);
 128         __set_bit(READ_CAPACITY, filter->read_ok);
 129         __set_bit(READ_LONG, filter->read_ok);
 130         __set_bit(INQUIRY, filter->read_ok);
 131         __set_bit(MODE_SENSE, filter->read_ok);
 132         __set_bit(MODE_SENSE_10, filter->read_ok);
 133         __set_bit(LOG_SENSE, filter->read_ok);
 134         __set_bit(START_STOP, filter->read_ok);
 135         __set_bit(GPCMD_VERIFY_10, filter->read_ok);
 136         __set_bit(VERIFY_16, filter->read_ok);
 137         __set_bit(REPORT_LUNS, filter->read_ok);
 138         __set_bit(SERVICE_ACTION_IN, filter->read_ok);
 139         __set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
 140         __set_bit(MAINTENANCE_IN, filter->read_ok);
 141         __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
 142
 143         /* Audio CD commands */
 144         __set_bit(GPCMD_PLAY_CD, filter->read_ok);
 145         __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
 146         __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
 147         __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
 148         __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
 149
 150         /* CD/DVD data reading */
 151         __set_bit(GPCMD_READ_CD, filter->read_ok);
 152         __set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
 153         __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
 154         __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
 155         __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
 156         __set_bit(GPCMD_READ_HEADER, filter->read_ok);
 157         __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
 158         __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
 159         __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
 160         __set_bit(GPCMD_REPORT_KEY, filter->read_ok);
 161         __set_bit(GPCMD_SCAN, filter->read_ok);
 162         __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
 163         __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
 164         __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
 165         __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
 166         __set_bit(GPCMD_SEEK, filter->read_ok);
 167         __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
 168
 169         /* Basic writing commands */
 170         __set_bit(WRITE_6, filter->write_ok);
 171         __set_bit(WRITE_10, filter->write_ok);
 172         __set_bit(WRITE_VERIFY, filter->write_ok);
 173         __set_bit(WRITE_12, filter->write_ok);
 174         __set_bit(WRITE_VERIFY_12, filter->write_ok);
 175         __set_bit(WRITE_16, filter->write_ok);
 176         __set_bit(WRITE_LONG, filter->write_ok);
 177         __set_bit(WRITE_LONG_2, filter->write_ok);
 178         __set_bit(ERASE, filter->write_ok);
 179         __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
 180         __set_bit(MODE_SELECT, filter->write_ok);
 181         __set_bit(LOG_SELECT, filter->write_ok);
 182         __set_bit(GPCMD_BLANK, filter->write_ok);
 183         __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
 184         __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
 185         __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
 186         __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
 187         __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
 188         __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
 189         __set_bit(GPCMD_SEND_EVENT, filter->write_ok);
 190         __set_bit(GPCMD_SEND_KEY, filter->write_ok);
 191         __set_bit(GPCMD_SEND_OPC, filter->write_ok);
 192         __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
 193         __set_bit(GPCMD_SET_SPEED, filter->write_ok);
 194         __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
 195         __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
 196         __set_bit(GPCMD_SET_STREAMING, filter->write_ok);
 197         __set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
 198 }
 199
 200 int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
 201 {
 202         struct blk_cmd_filter *filter = &blk_default_cmd_filter;
 203
 204         /* root can do any command. */
 205         if (capable(CAP_SYS_RAWIO))
 206                 return 0;
 207
 208         /* if there's no filter set, assume we're filtering everything out */
 209         if (!filter)
 210                 return -EPERM;
 211
 212         /* Anybody who can open the device can do a read-safe command */
 213         if (test_bit(cmd[0], filter->read_ok))
 214                 return 0;
 215
 216         /* Write-safe commands require a writable open */
 217         if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
 218                 return 0;
 219
 220         return -EPERM;
 221 }
 222 EXPORT_SYMBOL(blk_verify_command);
 223
 224 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
 225                              struct sg_io_hdr *hdr, fmode_t mode)
 226 {
 227         if (copy_from_user(rq->cmd, hdr->cmdp, hdr->cmd_len))
 228                 return -EFAULT;
 229         if (blk_verify_command(rq->cmd, mode & FMODE_WRITE))
 230                 return -EPERM;
 231
 232         /*
 233          * fill in request structure
 234          */
 235         rq->cmd_len = hdr->cmd_len;
 236         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 237
 238         rq->timeout = msecs_to_jiffies(hdr->timeout);
 239         if (!rq->timeout)
 240                 rq->timeout = q->sg_timeout;
 241         if (!rq->timeout)
 242                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 243         if (rq->timeout < BLK_MIN_SG_TIMEOUT)
 244                 rq->timeout = BLK_MIN_SG_TIMEOUT;
 245
 246         return 0;
 247 }
 248
 249 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 250                                  struct bio *bio)
 251 {
 252         int r, ret = 0;
 253
 254         /*
 255          * fill in all the output members
 256          */
 257         hdr->status = rq->errors & 0xff;
 258         hdr->masked_status = status_byte(rq->errors);
 259         hdr->msg_status = msg_byte(rq->errors);
 260         hdr->host_status = host_byte(rq->errors);
 261         hdr->driver_status = driver_byte(rq->errors);
 262         hdr->info = 0;
 263         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
 264                 hdr->info |= SG_INFO_CHECK;
 265         hdr->resid = rq->resid_len;
 266         hdr->sb_len_wr = 0;
 267
 268         if (rq->sense_len && hdr->sbp) {
 269                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
 270
 271                 if (!copy_to_user(hdr->sbp, rq->sense, len))
 272                         hdr->sb_len_wr = len;
 273                 else
 274                         ret = -EFAULT;
 275         }
 276
 277         r = blk_rq_unmap_user(bio);
 278         if (!ret)
 279                 ret = r;
 280         blk_put_request(rq);
 281
 282         return ret;
 283 }
 284
 285 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 286                 struct sg_io_hdr *hdr, fmode_t mode)
 287 {
 288         unsigned long start_time;
 289         ssize_t ret = 0;
 290         int writing = 0;
 291         struct request *rq;
 292         char sense[SCSI_SENSE_BUFFERSIZE];
 293         struct bio *bio;
 294
 295         if (hdr->interface_id != 'S')
 296                 return -EINVAL;
 297         if (hdr->cmd_len > BLK_MAX_CDB)
 298                 return -EINVAL;
 299
 300         if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
 301                 return -EIO;
 302
 303         if (hdr->dxfer_len)
 304                 switch (hdr->dxfer_direction) {
 305                 default:
 306                         return -EINVAL;
 307                 case SG_DXFER_TO_DEV:
 308                         writing = 1;
 309                         break;
 310                 case SG_DXFER_TO_FROM_DEV:
 311                 case SG_DXFER_FROM_DEV:
 312                         break;
 313                 }
 314
 315         rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
 316         if (!rq)
 317                 return -ENOMEM;
 318
 319         if (blk_fill_sghdr_rq(q, rq, hdr, mode)) {
 320                 blk_put_request(rq);
 321                 return -EFAULT;
 322         }
 323
 324         if (hdr->iovec_count) {
 325                 size_t iov_data_len;
 326                 struct iovec *iov = NULL;
 327
 328                 ret = rw_copy_check_uvector(-1, hdr->dxferp, hdr->iovec_count,
 329                                             0, NULL, &iov);
 330                 if (ret < 0) {
 331                         kfree(iov);
 332                         goto out;
 333                 }
 334
 335                 iov_data_len = ret;
 336                 ret = 0;
 337
 338                 /* SG_IO howto says that the shorter of the two wins */
 339                 if (hdr->dxfer_len < iov_data_len) {
 340                         hdr->iovec_count = iov_shorten(iov,
 341                                                        hdr->iovec_count,
 342                                                        hdr->dxfer_len);
 343                         iov_data_len = hdr->dxfer_len;
 344                 }
 345
 346                 ret = blk_rq_map_user_iov(q, rq, NULL, (struct sg_iovec *) iov,
 347                                           hdr->iovec_count,
 348                                           iov_data_len, GFP_KERNEL);
 349                 kfree(iov);
 350         } else if (hdr->dxfer_len)
 351                 ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
 352                                       GFP_KERNEL);
 353
 354         if (ret)
 355                 goto out;
 356
 357         bio = rq->bio;
 358         memset(sense, 0, sizeof(sense));
 359         rq->sense = sense;
 360         rq->sense_len = 0;
 361         rq->retries = 0;
 362
 363         start_time = jiffies;
 364
 365         /* ignore return value. All information is passed back to caller
 366          * (if he doesn't check that is his problem).
 367          * N.B. a non-zero SCSI status is _not_ necessarily an error.
 368          */
 369         blk_execute_rq(q, bd_disk, rq, 0);
 370
 371         hdr->duration = jiffies_to_msecs(jiffies - start_time);
 372
 373         return blk_complete_sghdr_rq(rq, hdr, bio);
 374 out:
 375         blk_put_request(rq);
 376         return ret;
 377 }
 378
 379 /**
 380  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
 381  * @file:       file this ioctl operates on (optional)
 382  * @q:          request queue to send scsi commands down
 383  * @disk:       gendisk to operate on (option)
 384  * @sic:        userspace structure describing the command to perform
 385  *
 386  * Send down the scsi command described by @sic to the device below
 387  * the request queue @q.  If @file is non-NULL it's used to perform
 388  * fine-grained permission checks that allow users to send down
 389  * non-destructive SCSI commands.  If the caller has a struct gendisk
 390  * available it should be passed in as @disk to allow the low level
 391  * driver to use the information contained in it.  A non-NULL @disk
 392  * is only allowed if the caller knows that the low level driver doesn't
 393  * need it (e.g. in the scsi subsystem).
 394  *
 395  * Notes:
 396  *   -  This interface is deprecated - users should use the SG_IO
 397  *      interface instead, as this is a more flexible approach to
 398  *      performing SCSI commands on a device.
 399  *   -  The SCSI command length is determined by examining the 1st byte
 400  *      of the given command. There is no way to override this.
 401  *   -  Data transfers are limited to PAGE_SIZE
 402  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
 403  *      accommodate the sense buffer when an error occurs.
 404  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
 405  *      old code will not be surprised.
 406  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
 407  *      a negative return and the Unix error code in 'errno'.
 408  *      If the SCSI command succeeds then 0 is returned.
 409  *      Positive numbers returned are the compacted SCSI error codes (4
 410  *      bytes in one int) where the lowest byte is the SCSI status.
 411  */
 412 #define OMAX_SB_LEN 16          /* For backward compatibility */
 413 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 414                 struct scsi_ioctl_command __user *sic)
 415 {
 416         struct request *rq;
 417         int err;
 418         unsigned int in_len, out_len, bytes, opcode, cmdlen;
 419         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
 420
 421         if (!sic)
 422                 return -EINVAL;
 423
 424         /*
 425          * get in an out lengths, verify they don't exceed a page worth of data
 426          */
 427         if (get_user(in_len, &sic->inlen))
 428                 return -EFAULT;
 429         if (get_user(out_len, &sic->outlen))
 430                 return -EFAULT;
 431         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
 432                 return -EINVAL;
 433         if (get_user(opcode, sic->data))
 434                 return -EFAULT;
 435
 436         bytes = max(in_len, out_len);
 437         if (bytes) {
 438                 buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
 439                 if (!buffer)
 440                         return -ENOMEM;
 441
 442         }
 443
 444         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
 445
 446         cmdlen = COMMAND_SIZE(opcode);
 447
 448         /*
 449          * get command and data to send to device, if any
 450          */
 451         err = -EFAULT;
 452         rq->cmd_len = cmdlen;
 453         if (copy_from_user(rq->cmd, sic->data, cmdlen))
 454                 goto error;
 455
 456         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
 457                 goto error;
 458
 459         err = blk_verify_command(rq->cmd, mode & FMODE_WRITE);
 460         if (err)
 461                 goto error;
 462
 463         /* default.  possible overriden later */
 464         rq->retries = 5;
 465
 466         switch (opcode) {
 467         case SEND_DIAGNOSTIC:
 468         case FORMAT_UNIT:
 469                 rq->timeout = FORMAT_UNIT_TIMEOUT;
 470                 rq->retries = 1;
 471                 break;
 472         case START_STOP:
 473                 rq->timeout = START_STOP_TIMEOUT;
 474                 break;
 475         case MOVE_MEDIUM:
 476                 rq->timeout = MOVE_MEDIUM_TIMEOUT;
 477                 break;
 478         case READ_ELEMENT_STATUS:
 479                 rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
 480                 break;
 481         case READ_DEFECT_DATA:
 482                 rq->timeout = READ_DEFECT_DATA_TIMEOUT;
 483                 rq->retries = 1;
 484                 break;
 485         default:
 486                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 487                 break;
 488         }
 489
 490         if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
 491                 err = DRIVER_ERROR << 24;
 492                 goto out;
 493         }
 494
 495         memset(sense, 0, sizeof(sense));
 496         rq->sense = sense;
 497         rq->sense_len = 0;
 498         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 499
 500         blk_execute_rq(q, disk, rq, 0);
 501
 502 out:
 503         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
 504         if (err) {
 505                 if (rq->sense_len && rq->sense) {
 506                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
 507                                 rq->sense_len : OMAX_SB_LEN;
 508                         if (copy_to_user(sic->data, rq->sense, bytes))
 509                                 err = -EFAULT;
 510                 }
 511         } else {
 512                 if (copy_to_user(sic->data, buffer, out_len))
 513                         err = -EFAULT;
 514         }
 515
 516 error:
 517         kfree(buffer);
 518         blk_put_request(rq);
 519         return err;
 520 }
 521 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
 522
 523 /* Send basic block requests */
 524 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
 525                               int cmd, int data)
 526 {
 527         struct request *rq;
 528         int err;
 529
 530         rq = blk_get_request(q, WRITE, __GFP_WAIT);
 531         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 532         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 533         rq->cmd[0] = cmd;
 534         rq->cmd[4] = data;
 535         rq->cmd_len = 6;
 536         err = blk_execute_rq(q, bd_disk, rq, 0);
 537         blk_put_request(rq);
 538
 539         return err;
 540 }
 541
 542 static inline int blk_send_start_stop(struct request_queue *q,
 543                                       struct gendisk *bd_disk, int data)
 544 {
 545         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
 546 }
 547
 548 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
 549                    unsigned int cmd, void __user *arg)
 550 {
 551         int err;
 552
 553         if (!q)
 554                 return -ENXIO;
 555
 556         switch (cmd) {
 557                 /*
 558                  * new sgv3 interface
 559                  */
 560                 case SG_GET_VERSION_NUM:
 561                         err = sg_get_version(arg);
 562                         break;
 563                 case SCSI_IOCTL_GET_IDLUN:
 564                         err = scsi_get_idlun(q, arg);
 565                         break;
 566                 case SCSI_IOCTL_GET_BUS_NUMBER:
 567                         err = scsi_get_bus(q, arg);
 568                         break;
 569                 case SG_SET_TIMEOUT:
 570                         err = sg_set_timeout(q, arg);
 571                         break;
 572                 case SG_GET_TIMEOUT:
 573                         err = sg_get_timeout(q);
 574                         break;
 575                 case SG_GET_RESERVED_SIZE:
 576                         err = sg_get_reserved_size(q, arg);
 577                         break;
 578                 case SG_SET_RESERVED_SIZE:
 579                         err = sg_set_reserved_size(q, arg);
 580                         break;
 581                 case SG_EMULATED_HOST:
 582                         err = sg_emulated_host(q, arg);
 583                         break;
 584                 case SG_IO: {
 585                         struct sg_io_hdr hdr;
 586
 587                         err = -EFAULT;
 588                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
 589                                 break;
 590                         err = sg_io(q, bd_disk, &hdr, mode);
 591                         if (err == -EFAULT)
 592                                 break;
 593
 594                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
 595                                 err = -EFAULT;
 596                         break;
 597                 }
 598                 case CDROM_SEND_PACKET: {
 599                         struct cdrom_generic_command cgc;
 600                         struct sg_io_hdr hdr;
 601
 602                         err = -EFAULT;
 603                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
 604                                 break;
 605                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
 606                         memset(&hdr, 0, sizeof(hdr));
 607                         hdr.interface_id = 'S';
 608                         hdr.cmd_len = sizeof(cgc.cmd);
 609                         hdr.dxfer_len = cgc.buflen;
 610                         err = 0;
 611                         switch (cgc.data_direction) {
 612                                 case CGC_DATA_UNKNOWN:
 613                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
 614                                         break;
 615                                 case CGC_DATA_WRITE:
 616                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
 617                                         break;
 618                                 case CGC_DATA_READ:
 619                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
 620                                         break;
 621                                 case CGC_DATA_NONE:
 622                                         hdr.dxfer_direction = SG_DXFER_NONE;
 623                                         break;
 624                                 default:
 625                                         err = -EINVAL;
 626                         }
 627                         if (err)
 628                                 break;
 629
 630                         hdr.dxferp = cgc.buffer;
 631                         hdr.sbp = cgc.sense;
 632                         if (hdr.sbp)
 633                                 hdr.mx_sb_len = sizeof(struct request_sense);
 634                         hdr.timeout = jiffies_to_msecs(cgc.timeout);
 635                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
 636                         hdr.cmd_len = sizeof(cgc.cmd);
 637
 638                         err = sg_io(q, bd_disk, &hdr, mode);
 639                         if (err == -EFAULT)
 640                                 break;
 641
 642                         if (hdr.status)
 643                                 err = -EIO;
 644
 645                         cgc.stat = err;
 646                         cgc.buflen = hdr.resid;
 647                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
 648                                 err = -EFAULT;
 649
 650                         break;
 651                 }
 652
 653                 /*
 654                  * old junk scsi send command ioctl
 655                  */
 656                 case SCSI_IOCTL_SEND_COMMAND:
 657                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
 658                         err = -EINVAL;
 659                         if (!arg)
 660                                 break;
 661
 662                         err = sg_scsi_ioctl(q, bd_disk, mode, arg);
 663                         break;
 664                 case CDROMCLOSETRAY:
 665                         err = blk_send_start_stop(q, bd_disk, 0x03);
 666                         break;
 667                 case CDROMEJECT:
 668                         err = blk_send_start_stop(q, bd_disk, 0x02);
 669                         break;
 670                 default:
 671                         err = -ENOTTY;
 672         }
 673
 674         return err;
 675 }
 676 EXPORT_SYMBOL(scsi_cmd_ioctl);
 677
 678 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
 679 {
 680         if (bd && bd == bd->bd_contains)
 681                 return 0;
 682
 683         /* Actually none of these is particularly useful on a partition,
 684          * but they are safe.
 685          */
 686         switch (cmd) {
 687         case SCSI_IOCTL_GET_IDLUN:
 688         case SCSI_IOCTL_GET_BUS_NUMBER:
 689         case SCSI_IOCTL_GET_PCI:
 690         case SCSI_IOCTL_PROBE_HOST:
 691         case SG_GET_VERSION_NUM:
 692         case SG_SET_TIMEOUT:
 693         case SG_GET_TIMEOUT:
 694         case SG_GET_RESERVED_SIZE:
 695         case SG_SET_RESERVED_SIZE:
 696         case SG_EMULATED_HOST:
 697                 return 0;
 698         case CDROM_GET_CAPABILITY:
 699                 /* Keep this until we remove the printk below.  udev sends it
 700                  * and we do not want to spam dmesg about it.   CD-ROMs do
 701                  * not have partitions, so we get here only for disks.
 702                  */
 703                 return -ENOIOCTLCMD;
 704         default:
 705                 break;
 706         }
 707
 708         if (capable(CAP_SYS_RAWIO))
 709                 return 0;
 710
 711         /* In particular, rule out all resets and host-specific ioctls.  */
 712         printk_ratelimited(KERN_WARNING
 713                            "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
 714
 715         return -ENOIOCTLCMD;
 716 }
 717 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
 718
 719 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
 720                        unsigned int cmd, void __user *arg)
 721 {
 722         int ret;
 723
 724         ret = scsi_verify_blk_ioctl(bd, cmd);
 725         if (ret < 0)
 726                 return ret;
 727
 728         return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
 729 }
 730 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
 731
 732 static int __init blk_scsi_ioctl_init(void)
 733 {
 734         blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
 735         return 0;
 736 }
 737 fs_initcall(blk_scsi_ioctl_init);