LXR linux/block/scsi

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
   4 */
   5#include <linux/kernel.h>
   6#include <linux/errno.h>
   7#include <linux/string.h>
   8#include <linux/module.h>
   9#include <linux/blkdev.h>
  10#include <linux/capability.h>
  11#include <linux/completion.h>
  12#include <linux/cdrom.h>
  13#include <linux/ratelimit.h>
  14#include <linux/slab.h>
  15#include <linux/times.h>
  16#include <linux/uio.h>
  17#include <linux/uaccess.h>
  18
  19#include <scsi/scsi.h>
  20#include <scsi/scsi_ioctl.h>
  21#include <scsi/scsi_cmnd.h>
  22
  23struct blk_cmd_filter {
  24        unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
  25        unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
  26};
  27
  28static struct blk_cmd_filter blk_default_cmd_filter;
  29
  30/* Command group 3 is reserved and should never be used.  */
  31const unsigned char scsi_command_size_tbl[8] =
  32{
  33        6, 10, 10, 12,
  34        16, 12, 10, 10
  35};
  36EXPORT_SYMBOL(scsi_command_size_tbl);
  37
  38#include <scsi/sg.h>
  39
  40static int sg_get_version(int __user *p)
  41{
  42        static const int sg_version_num = 30527;
  43        return put_user(sg_version_num, p);
  44}
  45
  46static int scsi_get_idlun(struct request_queue *q, int __user *p)
  47{
  48        return put_user(0, p);
  49}
  50
  51static int scsi_get_bus(struct request_queue *q, int __user *p)
  52{
  53        return put_user(0, p);
  54}
  55
  56static int sg_get_timeout(struct request_queue *q)
  57{
  58        return jiffies_to_clock_t(q->sg_timeout);
  59}
  60
  61static int sg_set_timeout(struct request_queue *q, int __user *p)
  62{
  63        int timeout, err = get_user(timeout, p);
  64
  65        if (!err)
  66                q->sg_timeout = clock_t_to_jiffies(timeout);
  67
  68        return err;
  69}
  70
  71static int max_sectors_bytes(struct request_queue *q)
  72{
  73        unsigned int max_sectors = queue_max_sectors(q);
  74
  75        max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
  76
  77        return max_sectors << 9;
  78}
  79
  80static int sg_get_reserved_size(struct request_queue *q, int __user *p)
  81{
  82        int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q));
  83
  84        return put_user(val, p);
  85}
  86
  87static int sg_set_reserved_size(struct request_queue *q, int __user *p)
  88{
  89        int size, err = get_user(size, p);
  90
  91        if (err)
  92                return err;
  93
  94        if (size < 0)
  95                return -EINVAL;
  96
  97        q->sg_reserved_size = min(size, max_sectors_bytes(q));
  98        return 0;
  99}
 100
 101/*
 102 * will always return that we are ATAPI even for a real SCSI drive, I'm not
 103 * so sure this is worth doing anything about (why would you care??)
 104 */
 105static int sg_emulated_host(struct request_queue *q, int __user *p)
 106{
 107        return put_user(1, p);
 108}
 109
 110static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
 111{
 112        /* Basic read-only commands */
 113        __set_bit(TEST_UNIT_READY, filter->read_ok);
 114        __set_bit(REQUEST_SENSE, filter->read_ok);
 115        __set_bit(READ_6, filter->read_ok);
 116        __set_bit(READ_10, filter->read_ok);
 117        __set_bit(READ_12, filter->read_ok);
 118        __set_bit(READ_16, filter->read_ok);
 119        __set_bit(READ_BUFFER, filter->read_ok);
 120        __set_bit(READ_DEFECT_DATA, filter->read_ok);
 121        __set_bit(READ_CAPACITY, filter->read_ok);
 122        __set_bit(READ_LONG, filter->read_ok);
 123        __set_bit(INQUIRY, filter->read_ok);
 124        __set_bit(MODE_SENSE, filter->read_ok);
 125        __set_bit(MODE_SENSE_10, filter->read_ok);
 126        __set_bit(LOG_SENSE, filter->read_ok);
 127        __set_bit(START_STOP, filter->read_ok);
 128        __set_bit(GPCMD_VERIFY_10, filter->read_ok);
 129        __set_bit(VERIFY_16, filter->read_ok);
 130        __set_bit(REPORT_LUNS, filter->read_ok);
 131        __set_bit(SERVICE_ACTION_IN_16, filter->read_ok);
 132        __set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
 133        __set_bit(MAINTENANCE_IN, filter->read_ok);
 134        __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
 135
 136        /* Audio CD commands */
 137        __set_bit(GPCMD_PLAY_CD, filter->read_ok);
 138        __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
 139        __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
 140        __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
 141        __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
 142
 143        /* CD/DVD data reading */
 144        __set_bit(GPCMD_READ_CD, filter->read_ok);
 145        __set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
 146        __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
 147        __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
 148        __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
 149        __set_bit(GPCMD_READ_HEADER, filter->read_ok);
 150        __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
 151        __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
 152        __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
 153        __set_bit(GPCMD_REPORT_KEY, filter->read_ok);
 154        __set_bit(GPCMD_SCAN, filter->read_ok);
 155        __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
 156        __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
 157        __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
 158        __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
 159        __set_bit(GPCMD_SEEK, filter->read_ok);
 160        __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
 161
 162        /* Basic writing commands */
 163        __set_bit(WRITE_6, filter->write_ok);
 164        __set_bit(WRITE_10, filter->write_ok);
 165        __set_bit(WRITE_VERIFY, filter->write_ok);
 166        __set_bit(WRITE_12, filter->write_ok);
 167        __set_bit(WRITE_VERIFY_12, filter->write_ok);
 168        __set_bit(WRITE_16, filter->write_ok);
 169        __set_bit(WRITE_LONG, filter->write_ok);
 170        __set_bit(WRITE_LONG_2, filter->write_ok);
 171        __set_bit(WRITE_SAME, filter->write_ok);
 172        __set_bit(WRITE_SAME_16, filter->write_ok);
 173        __set_bit(WRITE_SAME_32, filter->write_ok);
 174        __set_bit(ERASE, filter->write_ok);
 175        __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
 176        __set_bit(MODE_SELECT, filter->write_ok);
 177        __set_bit(LOG_SELECT, filter->write_ok);
 178        __set_bit(GPCMD_BLANK, filter->write_ok);
 179        __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
 180        __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
 181        __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
 182        __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
 183        __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
 184        __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
 185        __set_bit(GPCMD_SEND_EVENT, filter->write_ok);
 186        __set_bit(GPCMD_SEND_KEY, filter->write_ok);
 187        __set_bit(GPCMD_SEND_OPC, filter->write_ok);
 188        __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
 189        __set_bit(GPCMD_SET_SPEED, filter->write_ok);
 190        __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
 191        __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
 192        __set_bit(GPCMD_SET_STREAMING, filter->write_ok);
 193        __set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
 194}
 195
 196int blk_verify_command(unsigned char *cmd, fmode_t mode)
 197{
 198        struct blk_cmd_filter *filter = &blk_default_cmd_filter;
 199
 200        /* root can do any command. */
 201        if (capable(CAP_SYS_RAWIO))
 202                return 0;
 203
 204        /* Anybody who can open the device can do a read-safe command */
 205        if (test_bit(cmd[0], filter->read_ok))
 206                return 0;
 207
 208        /* Write-safe commands require a writable open */
 209        if (test_bit(cmd[0], filter->write_ok) && (mode & FMODE_WRITE))
 210                return 0;
 211
 212        return -EPERM;
 213}
 214EXPORT_SYMBOL(blk_verify_command);
 215
 216static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
 217                             struct sg_io_hdr *hdr, fmode_t mode)
 218{
 219        struct scsi_request *req = scsi_req(rq);
 220
 221        if (copy_from_user(req->cmd, hdr->cmdp, hdr->cmd_len))
 222                return -EFAULT;
 223        if (blk_verify_command(req->cmd, mode))
 224                return -EPERM;
 225
 226        /*
 227         * fill in request structure
 228         */
 229        req->cmd_len = hdr->cmd_len;
 230
 231        rq->timeout = msecs_to_jiffies(hdr->timeout);
 232        if (!rq->timeout)
 233                rq->timeout = q->sg_timeout;
 234        if (!rq->timeout)
 235                rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 236        if (rq->timeout < BLK_MIN_SG_TIMEOUT)
 237                rq->timeout = BLK_MIN_SG_TIMEOUT;
 238
 239        return 0;
 240}
 241
 242static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 243                                 struct bio *bio)
 244{
 245        struct scsi_request *req = scsi_req(rq);
 246        int r, ret = 0;
 247
 248        /*
 249         * fill in all the output members
 250         */
 251        hdr->status = req->result & 0xff;
 252        hdr->masked_status = status_byte(req->result);
 253        hdr->msg_status = msg_byte(req->result);
 254        hdr->host_status = host_byte(req->result);
 255        hdr->driver_status = driver_byte(req->result);
 256        hdr->info = 0;
 257        if (hdr->masked_status || hdr->host_status || hdr->driver_status)
 258                hdr->info |= SG_INFO_CHECK;
 259        hdr->resid = req->resid_len;
 260        hdr->sb_len_wr = 0;
 261
 262        if (req->sense_len && hdr->sbp) {
 263                int len = min((unsigned int) hdr->mx_sb_len, req->sense_len);
 264
 265                if (!copy_to_user(hdr->sbp, req->sense, len))
 266                        hdr->sb_len_wr = len;
 267                else
 268                        ret = -EFAULT;
 269        }
 270
 271        r = blk_rq_unmap_user(bio);
 272        if (!ret)
 273                ret = r;
 274
 275        return ret;
 276}
 277
 278static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 279                struct sg_io_hdr *hdr, fmode_t mode)
 280{
 281        unsigned long start_time;
 282        ssize_t ret = 0;
 283        int writing = 0;
 284        int at_head = 0;
 285        struct request *rq;
 286        struct scsi_request *req;
 287        struct bio *bio;
 288
 289        if (hdr->interface_id != 'S')
 290                return -EINVAL;
 291
 292        if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
 293                return -EIO;
 294
 295        if (hdr->dxfer_len)
 296                switch (hdr->dxfer_direction) {
 297                default:
 298                        return -EINVAL;
 299                case SG_DXFER_TO_DEV:
 300                        writing = 1;
 301                        break;
 302                case SG_DXFER_TO_FROM_DEV:
 303                case SG_DXFER_FROM_DEV:
 304                        break;
 305                }
 306        if (hdr->flags & SG_FLAG_Q_AT_HEAD)
 307                at_head = 1;
 308
 309        ret = -ENOMEM;
 310        rq = blk_get_request(q, writing ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
 311        if (IS_ERR(rq))
 312                return PTR_ERR(rq);
 313        req = scsi_req(rq);
 314
 315        if (hdr->cmd_len > BLK_MAX_CDB) {
 316                req->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
 317                if (!req->cmd)
 318                        goto out_put_request;
 319        }
 320
 321        ret = blk_fill_sghdr_rq(q, rq, hdr, mode);
 322        if (ret < 0)
 323                goto out_free_cdb;
 324
 325        ret = 0;
 326        if (hdr->iovec_count) {
 327                struct iov_iter i;
 328                struct iovec *iov = NULL;
 329
 330                ret = import_iovec(rq_data_dir(rq),
 331                                   hdr->dxferp, hdr->iovec_count,
 332                                   0, &iov, &i);
 333                if (ret < 0)
 334                        goto out_free_cdb;
 335
 336                /* SG_IO howto says that the shorter of the two wins */
 337                iov_iter_truncate(&i, hdr->dxfer_len);
 338
 339                ret = blk_rq_map_user_iov(q, rq, NULL, &i, GFP_KERNEL);
 340                kfree(iov);
 341        } else if (hdr->dxfer_len)
 342                ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
 343                                      GFP_KERNEL);
 344
 345        if (ret)
 346                goto out_free_cdb;
 347
 348        bio = rq->bio;
 349        req->retries = 0;
 350
 351        start_time = jiffies;
 352
 353        /* ignore return value. All information is passed back to caller
 354         * (if he doesn't check that is his problem).
 355         * N.B. a non-zero SCSI status is _not_ necessarily an error.
 356         */
 357        blk_execute_rq(q, bd_disk, rq, at_head);
 358
 359        hdr->duration = jiffies_to_msecs(jiffies - start_time);
 360
 361        ret = blk_complete_sghdr_rq(rq, hdr, bio);
 362
 363out_free_cdb:
 364        scsi_req_free_cmd(req);
 365out_put_request:
 366        blk_put_request(rq);
 367        return ret;
 368}
 369
 370/**
 371 * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
 372 * @q:          request queue to send scsi commands down
 373 * @disk:       gendisk to operate on (option)
 374 * @mode:       mode used to open the file through which the ioctl has been
 375 *              submitted
 376 * @sic:        userspace structure describing the command to perform
 377 *
 378 * Send down the scsi command described by @sic to the device below
 379 * the request queue @q.  If @file is non-NULL it's used to perform
 380 * fine-grained permission checks that allow users to send down
 381 * non-destructive SCSI commands.  If the caller has a struct gendisk
 382 * available it should be passed in as @disk to allow the low level
 383 * driver to use the information contained in it.  A non-NULL @disk
 384 * is only allowed if the caller knows that the low level driver doesn't
 385 * need it (e.g. in the scsi subsystem).
 386 *
 387 * Notes:
 388 *   -  This interface is deprecated - users should use the SG_IO
 389 *      interface instead, as this is a more flexible approach to
 390 *      performing SCSI commands on a device.
 391 *   -  The SCSI command length is determined by examining the 1st byte
 392 *      of the given command. There is no way to override this.
 393 *   -  Data transfers are limited to PAGE_SIZE
 394 *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
 395 *      accommodate the sense buffer when an error occurs.
 396 *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
 397 *      old code will not be surprised.
 398 *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
 399 *      a negative return and the Unix error code in 'errno'.
 400 *      If the SCSI command succeeds then 0 is returned.
 401 *      Positive numbers returned are the compacted SCSI error codes (4
 402 *      bytes in one int) where the lowest byte is the SCSI status.
 403 */
 404int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 405                struct scsi_ioctl_command __user *sic)
 406{
 407        enum { OMAX_SB_LEN = 16 };      /* For backward compatibility */
 408        struct request *rq;
 409        struct scsi_request *req;
 410        int err;
 411        unsigned int in_len, out_len, bytes, opcode, cmdlen;
 412        char *buffer = NULL;
 413
 414        if (!sic)
 415                return -EINVAL;
 416
 417        /*
 418         * get in an out lengths, verify they don't exceed a page worth of data
 419         */
 420        if (get_user(in_len, &sic->inlen))
 421                return -EFAULT;
 422        if (get_user(out_len, &sic->outlen))
 423                return -EFAULT;
 424        if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
 425                return -EINVAL;
 426        if (get_user(opcode, sic->data))
 427                return -EFAULT;
 428
 429        bytes = max(in_len, out_len);
 430        if (bytes) {
 431                buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
 432                if (!buffer)
 433                        return -ENOMEM;
 434
 435        }
 436
 437        rq = blk_get_request(q, in_len ? REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
 438        if (IS_ERR(rq)) {
 439                err = PTR_ERR(rq);
 440                goto error_free_buffer;
 441        }
 442        req = scsi_req(rq);
 443
 444        cmdlen = COMMAND_SIZE(opcode);
 445
 446        /*
 447         * get command and data to send to device, if any
 448         */
 449        err = -EFAULT;
 450        req->cmd_len = cmdlen;
 451        if (copy_from_user(req->cmd, sic->data, cmdlen))
 452                goto error;
 453
 454        if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
 455                goto error;
 456
 457        err = blk_verify_command(req->cmd, mode);
 458        if (err)
 459                goto error;
 460
 461        /* default.  possible overriden later */
 462        req->retries = 5;
 463
 464        switch (opcode) {
 465        case SEND_DIAGNOSTIC:
 466        case FORMAT_UNIT:
 467                rq->timeout = FORMAT_UNIT_TIMEOUT;
 468                req->retries = 1;
 469                break;
 470        case START_STOP:
 471                rq->timeout = START_STOP_TIMEOUT;
 472                break;
 473        case MOVE_MEDIUM:
 474                rq->timeout = MOVE_MEDIUM_TIMEOUT;
 475                break;
 476        case READ_ELEMENT_STATUS:
 477                rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
 478                break;
 479        case READ_DEFECT_DATA:
 480                rq->timeout = READ_DEFECT_DATA_TIMEOUT;
 481                req->retries = 1;
 482                break;
 483        default:
 484                rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 485                break;
 486        }
 487
 488        if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, GFP_NOIO)) {
 489                err = DRIVER_ERROR << 24;
 490                goto error;
 491        }
 492
 493        blk_execute_rq(q, disk, rq, 0);
 494
 495        err = req->result & 0xff;       /* only 8 bit SCSI status */
 496        if (err) {
 497                if (req->sense_len && req->sense) {
 498                        bytes = (OMAX_SB_LEN > req->sense_len) ?
 499                                req->sense_len : OMAX_SB_LEN;
 500                        if (copy_to_user(sic->data, req->sense, bytes))
 501                                err = -EFAULT;
 502                }
 503        } else {
 504                if (copy_to_user(sic->data, buffer, out_len))
 505                        err = -EFAULT;
 506        }
 507        
 508error:
 509        blk_put_request(rq);
 510
 511error_free_buffer:
 512        kfree(buffer);
 513
 514        return err;
 515}
 516EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
 517
 518/* Send basic block requests */
 519static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
 520                              int cmd, int data)
 521{
 522        struct request *rq;
 523        int err;
 524
 525        rq = blk_get_request(q, REQ_OP_SCSI_OUT, 0);
 526        if (IS_ERR(rq))
 527                return PTR_ERR(rq);
 528        rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 529        scsi_req(rq)->cmd[0] = cmd;
 530        scsi_req(rq)->cmd[4] = data;
 531        scsi_req(rq)->cmd_len = 6;
 532        blk_execute_rq(q, bd_disk, rq, 0);
 533        err = scsi_req(rq)->result ? -EIO : 0;
 534        blk_put_request(rq);
 535
 536        return err;
 537}
 538
 539static inline int blk_send_start_stop(struct request_queue *q,
 540                                      struct gendisk *bd_disk, int data)
 541{
 542        return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
 543}
 544
 545int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
 546                   unsigned int cmd, void __user *arg)
 547{
 548        int err;
 549
 550        if (!q)
 551                return -ENXIO;
 552
 553        switch (cmd) {
 554                /*
 555                 * new sgv3 interface
 556                 */
 557                case SG_GET_VERSION_NUM:
 558                        err = sg_get_version(arg);
 559                        break;
 560                case SCSI_IOCTL_GET_IDLUN:
 561                        err = scsi_get_idlun(q, arg);
 562                        break;
 563                case SCSI_IOCTL_GET_BUS_NUMBER:
 564                        err = scsi_get_bus(q, arg);
 565                        break;
 566                case SG_SET_TIMEOUT:
 567                        err = sg_set_timeout(q, arg);
 568                        break;
 569                case SG_GET_TIMEOUT:
 570                        err = sg_get_timeout(q);
 571                        break;
 572                case SG_GET_RESERVED_SIZE:
 573                        err = sg_get_reserved_size(q, arg);
 574                        break;
 575                case SG_SET_RESERVED_SIZE:
 576                        err = sg_set_reserved_size(q, arg);
 577                        break;
 578                case SG_EMULATED_HOST:
 579                        err = sg_emulated_host(q, arg);
 580                        break;
 581                case SG_IO: {
 582                        struct sg_io_hdr hdr;
 583
 584                        err = -EFAULT;
 585                        if (copy_from_user(&hdr, arg, sizeof(hdr)))
 586                                break;
 587                        err = sg_io(q, bd_disk, &hdr, mode);
 588                        if (err == -EFAULT)
 589                                break;
 590
 591                        if (copy_to_user(arg, &hdr, sizeof(hdr)))
 592                                err = -EFAULT;
 593                        break;
 594                }
 595                case CDROM_SEND_PACKET: {
 596                        struct cdrom_generic_command cgc;
 597                        struct sg_io_hdr hdr;
 598
 599                        err = -EFAULT;
 600                        if (copy_from_user(&cgc, arg, sizeof(cgc)))
 601                                break;
 602                        cgc.timeout = clock_t_to_jiffies(cgc.timeout);
 603                        memset(&hdr, 0, sizeof(hdr));
 604                        hdr.interface_id = 'S';
 605                        hdr.cmd_len = sizeof(cgc.cmd);
 606                        hdr.dxfer_len = cgc.buflen;
 607                        err = 0;
 608                        switch (cgc.data_direction) {
 609                                case CGC_DATA_UNKNOWN:
 610                                        hdr.dxfer_direction = SG_DXFER_UNKNOWN;
 611                                        break;
 612                                case CGC_DATA_WRITE:
 613                                        hdr.dxfer_direction = SG_DXFER_TO_DEV;
 614                                        break;
 615                                case CGC_DATA_READ:
 616                                        hdr.dxfer_direction = SG_DXFER_FROM_DEV;
 617                                        break;
 618                                case CGC_DATA_NONE:
 619                                        hdr.dxfer_direction = SG_DXFER_NONE;
 620                                        break;
 621                                default:
 622                                        err = -EINVAL;
 623                        }
 624                        if (err)
 625                                break;
 626
 627                        hdr.dxferp = cgc.buffer;
 628                        hdr.sbp = cgc.sense;
 629                        if (hdr.sbp)
 630                                hdr.mx_sb_len = sizeof(struct request_sense);
 631                        hdr.timeout = jiffies_to_msecs(cgc.timeout);
 632                        hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
 633                        hdr.cmd_len = sizeof(cgc.cmd);
 634
 635                        err = sg_io(q, bd_disk, &hdr, mode);
 636                        if (err == -EFAULT)
 637                                break;
 638
 639                        if (hdr.status)
 640                                err = -EIO;
 641
 642                        cgc.stat = err;
 643                        cgc.buflen = hdr.resid;
 644                        if (copy_to_user(arg, &cgc, sizeof(cgc)))
 645                                err = -EFAULT;
 646
 647                        break;
 648                }
 649
 650                /*
 651                 * old junk scsi send command ioctl
 652                 */
 653                case SCSI_IOCTL_SEND_COMMAND:
 654                        printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
 655                        err = -EINVAL;
 656                        if (!arg)
 657                                break;
 658
 659                        err = sg_scsi_ioctl(q, bd_disk, mode, arg);
 660                        break;
 661                case CDROMCLOSETRAY:
 662                        err = blk_send_start_stop(q, bd_disk, 0x03);
 663                        break;
 664                case CDROMEJECT:
 665                        err = blk_send_start_stop(q, bd_disk, 0x02);
 666                        break;
 667                default:
 668                        err = -ENOTTY;
 669        }
 670
 671        return err;
 672}
 673EXPORT_SYMBOL(scsi_cmd_ioctl);
 674
 675int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
 676{
 677        if (bd && bd == bd->bd_contains)
 678                return 0;
 679
 680        if (capable(CAP_SYS_RAWIO))
 681                return 0;
 682
 683        return -ENOIOCTLCMD;
 684}
 685EXPORT_SYMBOL(scsi_verify_blk_ioctl);
 686
 687int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
 688                       unsigned int cmd, void __user *arg)
 689{
 690        int ret;
 691
 692        ret = scsi_verify_blk_ioctl(bd, cmd);
 693        if (ret < 0)
 694                return ret;
 695
 696        return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
 697}
 698EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
 699
 700/**
 701 * scsi_req_init - initialize certain fields of a scsi_request structure
 702 * @req: Pointer to a scsi_request structure.
 703 * Initializes .__cmd[], .cmd, .cmd_len and .sense_len but no other members
 704 * of struct scsi_request.
 705 */
 706void scsi_req_init(struct scsi_request *req)
 707{
 708        memset(req->__cmd, 0, sizeof(req->__cmd));
 709        req->cmd = req->__cmd;
 710        req->cmd_len = BLK_MAX_CDB;
 711        req->sense_len = 0;
 712}
 713EXPORT_SYMBOL(scsi_req_init);
 714
 715static int __init blk_scsi_ioctl_init(void)
 716{
 717        blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
 718        return 0;
 719}
 720fs_initcall(blk_scsi_ioctl_init);
 721