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 <linux/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 max_sectors_bytes(struct request_queue *q)
  86 {
  87         unsigned int max_sectors = queue_max_sectors(q);
  88
  89         max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
  90
  91         return max_sectors << 9;
  92 }
  93
  94 static int sg_get_reserved_size(struct request_queue *q, int __user *p)
  95 {
  96         int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q));
  97
  98         return put_user(val, p);
  99 }
 100
 101 static int sg_set_reserved_size(struct request_queue *q, int __user *p)
 102 {
 103         int size, err = get_user(size, p);
 104
 105         if (err)
 106                 return err;
 107
 108         if (size < 0)
 109                 return -EINVAL;
 110
 111         q->sg_reserved_size = min(size, max_sectors_bytes(q));
 112         return 0;
 113 }
 114
 115 /*
 116  * will always return that we are ATAPI even for a real SCSI drive, I'm not
 117  * so sure this is worth doing anything about (why would you care??)
 118  */
 119 static int sg_emulated_host(struct request_queue *q, int __user *p)
 120 {
 121         return put_user(1, p);
 122 }
 123
 124 static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
 125 {
 126         /* Basic read-only commands */
 127         __set_bit(TEST_UNIT_READY, filter->read_ok);
 128         __set_bit(REQUEST_SENSE, filter->read_ok);
 129         __set_bit(READ_6, filter->read_ok);
 130         __set_bit(READ_10, filter->read_ok);
 131         __set_bit(READ_12, filter->read_ok);
 132         __set_bit(READ_16, filter->read_ok);
 133         __set_bit(READ_BUFFER, filter->read_ok);
 134         __set_bit(READ_DEFECT_DATA, filter->read_ok);
 135         __set_bit(READ_CAPACITY, filter->read_ok);
 136         __set_bit(READ_LONG, filter->read_ok);
 137         __set_bit(INQUIRY, filter->read_ok);
 138         __set_bit(MODE_SENSE, filter->read_ok);
 139         __set_bit(MODE_SENSE_10, filter->read_ok);
 140         __set_bit(LOG_SENSE, filter->read_ok);
 141         __set_bit(START_STOP, filter->read_ok);
 142         __set_bit(GPCMD_VERIFY_10, filter->read_ok);
 143         __set_bit(VERIFY_16, filter->read_ok);
 144         __set_bit(REPORT_LUNS, filter->read_ok);
 145         __set_bit(SERVICE_ACTION_IN_16, filter->read_ok);
 146         __set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
 147         __set_bit(MAINTENANCE_IN, filter->read_ok);
 148         __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
 149
 150         /* Audio CD commands */
 151         __set_bit(GPCMD_PLAY_CD, filter->read_ok);
 152         __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
 153         __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
 154         __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
 155         __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
 156
 157         /* CD/DVD data reading */
 158         __set_bit(GPCMD_READ_CD, filter->read_ok);
 159         __set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
 160         __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
 161         __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
 162         __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
 163         __set_bit(GPCMD_READ_HEADER, filter->read_ok);
 164         __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
 165         __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
 166         __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
 167         __set_bit(GPCMD_REPORT_KEY, filter->read_ok);
 168         __set_bit(GPCMD_SCAN, filter->read_ok);
 169         __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
 170         __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
 171         __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
 172         __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
 173         __set_bit(GPCMD_SEEK, filter->read_ok);
 174         __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
 175
 176         /* Basic writing commands */
 177         __set_bit(WRITE_6, filter->write_ok);
 178         __set_bit(WRITE_10, filter->write_ok);
 179         __set_bit(WRITE_VERIFY, filter->write_ok);
 180         __set_bit(WRITE_12, filter->write_ok);
 181         __set_bit(WRITE_VERIFY_12, filter->write_ok);
 182         __set_bit(WRITE_16, filter->write_ok);
 183         __set_bit(WRITE_LONG, filter->write_ok);
 184         __set_bit(WRITE_LONG_2, filter->write_ok);
 185         __set_bit(WRITE_SAME, filter->write_ok);
 186         __set_bit(WRITE_SAME_16, filter->write_ok);
 187         __set_bit(WRITE_SAME_32, filter->write_ok);
 188         __set_bit(ERASE, filter->write_ok);
 189         __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
 190         __set_bit(MODE_SELECT, filter->write_ok);
 191         __set_bit(LOG_SELECT, filter->write_ok);
 192         __set_bit(GPCMD_BLANK, filter->write_ok);
 193         __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
 194         __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
 195         __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
 196         __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
 197         __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
 198         __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
 199         __set_bit(GPCMD_SEND_EVENT, filter->write_ok);
 200         __set_bit(GPCMD_SEND_KEY, filter->write_ok);
 201         __set_bit(GPCMD_SEND_OPC, filter->write_ok);
 202         __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
 203         __set_bit(GPCMD_SET_SPEED, filter->write_ok);
 204         __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
 205         __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
 206         __set_bit(GPCMD_SET_STREAMING, filter->write_ok);
 207         __set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
 208 }
 209
 210 int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
 211 {
 212         struct blk_cmd_filter *filter = &blk_default_cmd_filter;
 213
 214         /* root can do any command. */
 215         if (capable(CAP_SYS_RAWIO))
 216                 return 0;
 217
 218         /* Anybody who can open the device can do a read-safe command */
 219         if (test_bit(cmd[0], filter->read_ok))
 220                 return 0;
 221
 222         /* Write-safe commands require a writable open */
 223         if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
 224                 return 0;
 225
 226         return -EPERM;
 227 }
 228 EXPORT_SYMBOL(blk_verify_command);
 229
 230 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
 231                              struct sg_io_hdr *hdr, fmode_t mode)
 232 {
 233         struct scsi_request *req = scsi_req(rq);
 234
 235         if (copy_from_user(req->cmd, hdr->cmdp, hdr->cmd_len))
 236                 return -EFAULT;
 237         if (blk_verify_command(req->cmd, mode & FMODE_WRITE))
 238                 return -EPERM;
 239
 240         /*
 241          * fill in request structure
 242          */
 243         req->cmd_len = hdr->cmd_len;
 244
 245         rq->timeout = msecs_to_jiffies(hdr->timeout);
 246         if (!rq->timeout)
 247                 rq->timeout = q->sg_timeout;
 248         if (!rq->timeout)
 249                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 250         if (rq->timeout < BLK_MIN_SG_TIMEOUT)
 251                 rq->timeout = BLK_MIN_SG_TIMEOUT;
 252
 253         return 0;
 254 }
 255
 256 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 257                                  struct bio *bio)
 258 {
 259         struct scsi_request *req = scsi_req(rq);
 260         int r, ret = 0;
 261
 262         /*
 263          * fill in all the output members
 264          */
 265         hdr->status = req->result & 0xff;
 266         hdr->masked_status = status_byte(req->result);
 267         hdr->msg_status = msg_byte(req->result);
 268         hdr->host_status = host_byte(req->result);
 269         hdr->driver_status = driver_byte(req->result);
 270         hdr->info = 0;
 271         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
 272                 hdr->info |= SG_INFO_CHECK;
 273         hdr->resid = req->resid_len;
 274         hdr->sb_len_wr = 0;
 275
 276         if (req->sense_len && hdr->sbp) {
 277                 int len = min((unsigned int) hdr->mx_sb_len, req->sense_len);
 278
 279                 if (!copy_to_user(hdr->sbp, req->sense, len))
 280                         hdr->sb_len_wr = len;
 281                 else
 282                         ret = -EFAULT;
 283         }
 284
 285         r = blk_rq_unmap_user(bio);
 286         if (!ret)
 287                 ret = r;
 288
 289         return ret;
 290 }
 291
 292 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 293                 struct sg_io_hdr *hdr, fmode_t mode)
 294 {
 295         unsigned long start_time;
 296         ssize_t ret = 0;
 297         int writing = 0;
 298         int at_head = 0;
 299         struct request *rq;
 300         struct scsi_request *req;
 301         struct bio *bio;
 302
 303         if (hdr->interface_id != 'S')
 304                 return -EINVAL;
 305
 306         if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
 307                 return -EIO;
 308
 309         if (hdr->dxfer_len)
 310                 switch (hdr->dxfer_direction) {
 311                 default:
 312                         return -EINVAL;
 313                 case SG_DXFER_TO_DEV:
 314                         writing = 1;
 315                         break;
 316                 case SG_DXFER_TO_FROM_DEV:
 317                 case SG_DXFER_FROM_DEV:
 318                         break;
 319                 }
 320         if (hdr->flags & SG_FLAG_Q_AT_HEAD)
 321                 at_head = 1;
 322
 323         ret = -ENOMEM;
 324         rq = blk_get_request(q, writing ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN,
 325                         GFP_KERNEL);
 326         if (IS_ERR(rq))
 327                 return PTR_ERR(rq);
 328         req = scsi_req(rq);
 329
 330         if (hdr->cmd_len > BLK_MAX_CDB) {
 331                 req->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
 332                 if (!req->cmd)
 333                         goto out_put_request;
 334         }
 335
 336         ret = blk_fill_sghdr_rq(q, rq, hdr, mode);
 337         if (ret < 0)
 338                 goto out_free_cdb;
 339
 340         ret = 0;
 341         if (hdr->iovec_count) {
 342                 struct iov_iter i;
 343                 struct iovec *iov = NULL;
 344
 345                 ret = import_iovec(rq_data_dir(rq),
 346                                    hdr->dxferp, hdr->iovec_count,
 347                                    0, &iov, &i);
 348                 if (ret < 0)
 349                         goto out_free_cdb;
 350
 351                 /* SG_IO howto says that the shorter of the two wins */
 352                 iov_iter_truncate(&i, hdr->dxfer_len);
 353
 354                 ret = blk_rq_map_user_iov(q, rq, NULL, &i, GFP_KERNEL);
 355                 kfree(iov);
 356         } else if (hdr->dxfer_len)
 357                 ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
 358                                       GFP_KERNEL);
 359
 360         if (ret)
 361                 goto out_free_cdb;
 362
 363         bio = rq->bio;
 364         req->retries = 0;
 365
 366         start_time = jiffies;
 367
 368         /* ignore return value. All information is passed back to caller
 369          * (if he doesn't check that is his problem).
 370          * N.B. a non-zero SCSI status is _not_ necessarily an error.
 371          */
 372         blk_execute_rq(q, bd_disk, rq, at_head);
 373
 374         hdr->duration = jiffies_to_msecs(jiffies - start_time);
 375
 376         ret = blk_complete_sghdr_rq(rq, hdr, bio);
 377
 378 out_free_cdb:
 379         scsi_req_free_cmd(req);
 380 out_put_request:
 381         blk_put_request(rq);
 382         return ret;
 383 }
 384
 385 /**
 386  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
 387  * @file:       file this ioctl operates on (optional)
 388  * @q:          request queue to send scsi commands down
 389  * @disk:       gendisk to operate on (option)
 390  * @sic:        userspace structure describing the command to perform
 391  *
 392  * Send down the scsi command described by @sic to the device below
 393  * the request queue @q.  If @file is non-NULL it's used to perform
 394  * fine-grained permission checks that allow users to send down
 395  * non-destructive SCSI commands.  If the caller has a struct gendisk
 396  * available it should be passed in as @disk to allow the low level
 397  * driver to use the information contained in it.  A non-NULL @disk
 398  * is only allowed if the caller knows that the low level driver doesn't
 399  * need it (e.g. in the scsi subsystem).
 400  *
 401  * Notes:
 402  *   -  This interface is deprecated - users should use the SG_IO
 403  *      interface instead, as this is a more flexible approach to
 404  *      performing SCSI commands on a device.
 405  *   -  The SCSI command length is determined by examining the 1st byte
 406  *      of the given command. There is no way to override this.
 407  *   -  Data transfers are limited to PAGE_SIZE
 408  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
 409  *      accommodate the sense buffer when an error occurs.
 410  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
 411  *      old code will not be surprised.
 412  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
 413  *      a negative return and the Unix error code in 'errno'.
 414  *      If the SCSI command succeeds then 0 is returned.
 415  *      Positive numbers returned are the compacted SCSI error codes (4
 416  *      bytes in one int) where the lowest byte is the SCSI status.
 417  */
 418 #define OMAX_SB_LEN 16          /* For backward compatibility */
 419 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 420                 struct scsi_ioctl_command __user *sic)
 421 {
 422         struct request *rq;
 423         struct scsi_request *req;
 424         int err;
 425         unsigned int in_len, out_len, bytes, opcode, cmdlen;
 426         char *buffer = NULL;
 427
 428         if (!sic)
 429                 return -EINVAL;
 430
 431         /*
 432          * get in an out lengths, verify they don't exceed a page worth of data
 433          */
 434         if (get_user(in_len, &sic->inlen))
 435                 return -EFAULT;
 436         if (get_user(out_len, &sic->outlen))
 437                 return -EFAULT;
 438         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
 439                 return -EINVAL;
 440         if (get_user(opcode, sic->data))
 441                 return -EFAULT;
 442
 443         bytes = max(in_len, out_len);
 444         if (bytes) {
 445                 buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
 446                 if (!buffer)
 447                         return -ENOMEM;
 448
 449         }
 450
 451         rq = blk_get_request(q, in_len ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN,
 452                         __GFP_RECLAIM);
 453         if (IS_ERR(rq)) {
 454                 err = PTR_ERR(rq);
 455                 goto error_free_buffer;
 456         }
 457         req = scsi_req(rq);
 458
 459         cmdlen = COMMAND_SIZE(opcode);
 460
 461         /*
 462          * get command and data to send to device, if any
 463          */
 464         err = -EFAULT;
 465         req->cmd_len = cmdlen;
 466         if (copy_from_user(req->cmd, sic->data, cmdlen))
 467                 goto error;
 468
 469         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
 470                 goto error;
 471
 472         err = blk_verify_command(req->cmd, mode & FMODE_WRITE);
 473         if (err)
 474                 goto error;
 475
 476         /* default.  possible overriden later */
 477         req->retries = 5;
 478
 479         switch (opcode) {
 480         case SEND_DIAGNOSTIC:
 481         case FORMAT_UNIT:
 482                 rq->timeout = FORMAT_UNIT_TIMEOUT;
 483                 req->retries = 1;
 484                 break;
 485         case START_STOP:
 486                 rq->timeout = START_STOP_TIMEOUT;
 487                 break;
 488         case MOVE_MEDIUM:
 489                 rq->timeout = MOVE_MEDIUM_TIMEOUT;
 490                 break;
 491         case READ_ELEMENT_STATUS:
 492                 rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
 493                 break;
 494         case READ_DEFECT_DATA:
 495                 rq->timeout = READ_DEFECT_DATA_TIMEOUT;
 496                 req->retries = 1;
 497                 break;
 498         default:
 499                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 500                 break;
 501         }
 502
 503         if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_RECLAIM)) {
 504                 err = DRIVER_ERROR << 24;
 505                 goto error;
 506         }
 507
 508         blk_execute_rq(q, disk, rq, 0);
 509
 510         err = req->result & 0xff;       /* only 8 bit SCSI status */
 511         if (err) {
 512                 if (req->sense_len && req->sense) {
 513                         bytes = (OMAX_SB_LEN > req->sense_len) ?
 514                                 req->sense_len : OMAX_SB_LEN;
 515                         if (copy_to_user(sic->data, req->sense, bytes))
 516                                 err = -EFAULT;
 517                 }
 518         } else {
 519                 if (copy_to_user(sic->data, buffer, out_len))
 520                         err = -EFAULT;
 521         }
 522
 523 error:
 524         blk_put_request(rq);
 525
 526 error_free_buffer:
 527         kfree(buffer);
 528
 529         return err;
 530 }
 531 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
 532
 533 /* Send basic block requests */
 534 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
 535                               int cmd, int data)
 536 {
 537         struct request *rq;
 538         int err;
 539
 540         rq = blk_get_request(q, REQ_OP_SCSI_OUT, __GFP_RECLAIM);
 541         if (IS_ERR(rq))
 542                 return PTR_ERR(rq);
 543         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 544         scsi_req(rq)->cmd[0] = cmd;
 545         scsi_req(rq)->cmd[4] = data;
 546         scsi_req(rq)->cmd_len = 6;
 547         blk_execute_rq(q, bd_disk, rq, 0);
 548         err = scsi_req(rq)->result ? -EIO : 0;
 549         blk_put_request(rq);
 550
 551         return err;
 552 }
 553
 554 static inline int blk_send_start_stop(struct request_queue *q,
 555                                       struct gendisk *bd_disk, int data)
 556 {
 557         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
 558 }
 559
 560 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
 561                    unsigned int cmd, void __user *arg)
 562 {
 563         int err;
 564
 565         if (!q)
 566                 return -ENXIO;
 567
 568         switch (cmd) {
 569                 /*
 570                  * new sgv3 interface
 571                  */
 572                 case SG_GET_VERSION_NUM:
 573                         err = sg_get_version(arg);
 574                         break;
 575                 case SCSI_IOCTL_GET_IDLUN:
 576                         err = scsi_get_idlun(q, arg);
 577                         break;
 578                 case SCSI_IOCTL_GET_BUS_NUMBER:
 579                         err = scsi_get_bus(q, arg);
 580                         break;
 581                 case SG_SET_TIMEOUT:
 582                         err = sg_set_timeout(q, arg);
 583                         break;
 584                 case SG_GET_TIMEOUT:
 585                         err = sg_get_timeout(q);
 586                         break;
 587                 case SG_GET_RESERVED_SIZE:
 588                         err = sg_get_reserved_size(q, arg);
 589                         break;
 590                 case SG_SET_RESERVED_SIZE:
 591                         err = sg_set_reserved_size(q, arg);
 592                         break;
 593                 case SG_EMULATED_HOST:
 594                         err = sg_emulated_host(q, arg);
 595                         break;
 596                 case SG_IO: {
 597                         struct sg_io_hdr hdr;
 598
 599                         err = -EFAULT;
 600                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
 601                                 break;
 602                         err = sg_io(q, bd_disk, &hdr, mode);
 603                         if (err == -EFAULT)
 604                                 break;
 605
 606                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
 607                                 err = -EFAULT;
 608                         break;
 609                 }
 610                 case CDROM_SEND_PACKET: {
 611                         struct cdrom_generic_command cgc;
 612                         struct sg_io_hdr hdr;
 613
 614                         err = -EFAULT;
 615                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
 616                                 break;
 617                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
 618                         memset(&hdr, 0, sizeof(hdr));
 619                         hdr.interface_id = 'S';
 620                         hdr.cmd_len = sizeof(cgc.cmd);
 621                         hdr.dxfer_len = cgc.buflen;
 622                         err = 0;
 623                         switch (cgc.data_direction) {
 624                                 case CGC_DATA_UNKNOWN:
 625                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
 626                                         break;
 627                                 case CGC_DATA_WRITE:
 628                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
 629                                         break;
 630                                 case CGC_DATA_READ:
 631                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
 632                                         break;
 633                                 case CGC_DATA_NONE:
 634                                         hdr.dxfer_direction = SG_DXFER_NONE;
 635                                         break;
 636                                 default:
 637                                         err = -EINVAL;
 638                         }
 639                         if (err)
 640                                 break;
 641
 642                         hdr.dxferp = cgc.buffer;
 643                         hdr.sbp = cgc.sense;
 644                         if (hdr.sbp)
 645                                 hdr.mx_sb_len = sizeof(struct request_sense);
 646                         hdr.timeout = jiffies_to_msecs(cgc.timeout);
 647                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
 648                         hdr.cmd_len = sizeof(cgc.cmd);
 649
 650                         err = sg_io(q, bd_disk, &hdr, mode);
 651                         if (err == -EFAULT)
 652                                 break;
 653
 654                         if (hdr.status)
 655                                 err = -EIO;
 656
 657                         cgc.stat = err;
 658                         cgc.buflen = hdr.resid;
 659                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
 660                                 err = -EFAULT;
 661
 662                         break;
 663                 }
 664
 665                 /*
 666                  * old junk scsi send command ioctl
 667                  */
 668                 case SCSI_IOCTL_SEND_COMMAND:
 669                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
 670                         err = -EINVAL;
 671                         if (!arg)
 672                                 break;
 673
 674                         err = sg_scsi_ioctl(q, bd_disk, mode, arg);
 675                         break;
 676                 case CDROMCLOSETRAY:
 677                         err = blk_send_start_stop(q, bd_disk, 0x03);
 678                         break;
 679                 case CDROMEJECT:
 680                         err = blk_send_start_stop(q, bd_disk, 0x02);
 681                         break;
 682                 default:
 683                         err = -ENOTTY;
 684         }
 685
 686         return err;
 687 }
 688 EXPORT_SYMBOL(scsi_cmd_ioctl);
 689
 690 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
 691 {
 692         if (bd && bd == bd->bd_contains)
 693                 return 0;
 694
 695         /* Actually none of these is particularly useful on a partition,
 696          * but they are safe.
 697          */
 698         switch (cmd) {
 699         case SCSI_IOCTL_GET_IDLUN:
 700         case SCSI_IOCTL_GET_BUS_NUMBER:
 701         case SCSI_IOCTL_GET_PCI:
 702         case SCSI_IOCTL_PROBE_HOST:
 703         case SG_GET_VERSION_NUM:
 704         case SG_SET_TIMEOUT:
 705         case SG_GET_TIMEOUT:
 706         case SG_GET_RESERVED_SIZE:
 707         case SG_SET_RESERVED_SIZE:
 708         case SG_EMULATED_HOST:
 709                 return 0;
 710         case CDROM_GET_CAPABILITY:
 711                 /* Keep this until we remove the printk below.  udev sends it
 712                  * and we do not want to spam dmesg about it.   CD-ROMs do
 713                  * not have partitions, so we get here only for disks.
 714                  */
 715                 return -ENOIOCTLCMD;
 716         default:
 717                 break;
 718         }
 719
 720         if (capable(CAP_SYS_RAWIO))
 721                 return 0;
 722
 723         /* In particular, rule out all resets and host-specific ioctls.  */
 724         printk_ratelimited(KERN_WARNING
 725                            "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
 726
 727         return -ENOIOCTLCMD;
 728 }
 729 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
 730
 731 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
 732                        unsigned int cmd, void __user *arg)
 733 {
 734         int ret;
 735
 736         ret = scsi_verify_blk_ioctl(bd, cmd);
 737         if (ret < 0)
 738                 return ret;
 739
 740         return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
 741 }
 742 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
 743
 744 /**
 745  * scsi_req_init - initialize certain fields of a scsi_request structure
 746  * @req: Pointer to a scsi_request structure.
 747  * Initializes .__cmd[], .cmd, .cmd_len and .sense_len but no other members
 748  * of struct scsi_request.
 749  */
 750 void scsi_req_init(struct scsi_request *req)
 751 {
 752         memset(req->__cmd, 0, sizeof(req->__cmd));
 753         req->cmd = req->__cmd;
 754         req->cmd_len = BLK_MAX_CDB;
 755         req->sense_len = 0;
 756 }
 757 EXPORT_SYMBOL(scsi_req_init);
 758
 759 static int __init blk_scsi_ioctl_init(void)
 760 {
 761         blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
 762         return 0;
 763 }
 764 fs_initcall(blk_scsi_ioctl_init);