drivers/usb/storage/scsiglue.c

   1 /* Driver for USB Mass Storage compliant devices
   2  * SCSI layer glue code
   3  *
   4  * Current development and maintenance by:
   5  *   (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
   6  *
   7  * Developed with the assistance of:
   8  *   (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
   9  *   (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
  10  *
  11  * Initial work by:
  12  *   (c) 1999 Michael Gee (michael@linuxspecific.com)
  13  *
  14  * This driver is based on the 'USB Mass Storage Class' document. This
  15  * describes in detail the protocol used to communicate with such
  16  * devices.  Clearly, the designers had SCSI and ATAPI commands in
  17  * mind when they created this document.  The commands are all very
  18  * similar to commands in the SCSI-II and ATAPI specifications.
  19  *
  20  * It is important to note that in a number of cases this class
  21  * exhibits class-specific exemptions from the USB specification.
  22  * Notably the usage of NAK, STALL and ACK differs from the norm, in
  23  * that they are used to communicate wait, failed and OK on commands.
  24  *
  25  * Also, for certain devices, the interrupt endpoint is used to convey
  26  * status of a command.
  27  *
  28  * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
  29  * information about this driver.
  30  *
  31  * This program is free software; you can redistribute it and/or modify it
  32  * under the terms of the GNU General Public License as published by the
  33  * Free Software Foundation; either version 2, or (at your option) any
  34  * later version.
  35  *
  36  * This program is distributed in the hope that it will be useful, but
  37  * WITHOUT ANY WARRANTY; without even the implied warranty of
  38  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  39  * General Public License for more details.
  40  *
  41  * You should have received a copy of the GNU General Public License along
  42  * with this program; if not, write to the Free Software Foundation, Inc.,
  43  * 675 Mass Ave, Cambridge, MA 02139, USA.
  44  */
  45
  46 #include <linux/module.h>
  47 #include <linux/mutex.h>
  48
  49 #include <scsi/scsi.h>
  50 #include <scsi/scsi_cmnd.h>
  51 #include <scsi/scsi_devinfo.h>
  52 #include <scsi/scsi_device.h>
  53 #include <scsi/scsi_eh.h>
  54
  55 #include "usb.h"
  56 #include "scsiglue.h"
  57 #include "debug.h"
  58 #include "transport.h"
  59 #include "protocol.h"
  60
  61 /* Vendor IDs for companies that seem to include the READ CAPACITY bug
  62  * in all their devices
  63  */
  64 #define VENDOR_ID_NOKIA         0x0421
  65 #define VENDOR_ID_NIKON         0x04b0
  66 #define VENDOR_ID_PENTAX        0x0a17
  67 #define VENDOR_ID_MOTOROLA      0x22b8
  68
  69 /***********************************************************************
  70  * Host functions
  71  ***********************************************************************/
  72
  73 static const char* host_info(struct Scsi_Host *host)
  74 {
  75         struct us_data *us = host_to_us(host);
  76         return us->scsi_name;
  77 }
  78
  79 static int slave_alloc (struct scsi_device *sdev)
  80 {
  81         struct us_data *us = host_to_us(sdev->host);
  82
  83         /*
  84          * Set the INQUIRY transfer length to 36.  We don't use any of
  85          * the extra data and many devices choke if asked for more or
  86          * less than 36 bytes.
  87          */
  88         sdev->inquiry_len = 36;
  89
  90         /* USB has unusual DMA-alignment requirements: Although the
  91          * starting address of each scatter-gather element doesn't matter,
  92          * the length of each element except the last must be divisible
  93          * by the Bulk maxpacket value.  There's currently no way to
  94          * express this by block-layer constraints, so we'll cop out
  95          * and simply require addresses to be aligned at 512-byte
  96          * boundaries.  This is okay since most block I/O involves
  97          * hardware sectors that are multiples of 512 bytes in length,
  98          * and since host controllers up through USB 2.0 have maxpacket
  99          * values no larger than 512.
 100          *
 101          * But it doesn't suffice for Wireless USB, where Bulk maxpacket
 102          * values can be as large as 2048.  To make that work properly
 103          * will require changes to the block layer.
 104          */
 105         blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
 106
 107         /* Tell the SCSI layer if we know there is more than one LUN */
 108         if (us->protocol == USB_PR_BULK && us->max_lun > 0)
 109                 sdev->sdev_bflags |= BLIST_FORCELUN;
 110
 111         return 0;
 112 }
 113
 114 static int slave_configure(struct scsi_device *sdev)
 115 {
 116         struct us_data *us = host_to_us(sdev->host);
 117
 118         /* Many devices have trouble transferring more than 32KB at a time,
 119          * while others have trouble with more than 64K. At this time we
 120          * are limiting both to 32K (64 sectores).
 121          */
 122         if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
 123                 unsigned int max_sectors = 64;
 124
 125                 if (us->fflags & US_FL_MAX_SECTORS_MIN)
 126                         max_sectors = PAGE_SIZE >> 9;
 127                 if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
 128                         blk_queue_max_hw_sectors(sdev->request_queue,
 129                                               max_sectors);
 130         } else if (sdev->type == TYPE_TAPE) {
 131                 /* Tapes need much higher max_sector limits, so just
 132                  * raise it to the maximum possible (4 GB / 512) and
 133                  * let the queue segment size sort out the real limit.
 134                  */
 135                 blk_queue_max_hw_sectors(sdev->request_queue, 0x7FFFFF);
 136         }
 137
 138         /* Some USB host controllers can't do DMA; they have to use PIO.
 139          * They indicate this by setting their dma_mask to NULL.  For
 140          * such controllers we need to make sure the block layer sets
 141          * up bounce buffers in addressable memory.
 142          */
 143         if (!us->pusb_dev->bus->controller->dma_mask)
 144                 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
 145
 146         /* We can't put these settings in slave_alloc() because that gets
 147          * called before the device type is known.  Consequently these
 148          * settings can't be overridden via the scsi devinfo mechanism. */
 149         if (sdev->type == TYPE_DISK) {
 150
 151                 /* Some vendors seem to put the READ CAPACITY bug into
 152                  * all their devices -- primarily makers of cell phones
 153                  * and digital cameras.  Since these devices always use
 154                  * flash media and can be expected to have an even number
 155                  * of sectors, we will always enable the CAPACITY_HEURISTICS
 156                  * flag unless told otherwise. */
 157                 switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
 158                 case VENDOR_ID_NOKIA:
 159                 case VENDOR_ID_NIKON:
 160                 case VENDOR_ID_PENTAX:
 161                 case VENDOR_ID_MOTOROLA:
 162                         if (!(us->fflags & (US_FL_FIX_CAPACITY |
 163                                         US_FL_CAPACITY_OK)))
 164                                 us->fflags |= US_FL_CAPACITY_HEURISTICS;
 165                         break;
 166                 }
 167
 168                 /* Disk-type devices use MODE SENSE(6) if the protocol
 169                  * (SubClass) is Transparent SCSI, otherwise they use
 170                  * MODE SENSE(10). */
 171                 if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
 172                         sdev->use_10_for_ms = 1;
 173
 174                 /* Many disks only accept MODE SENSE transfer lengths of
 175                  * 192 bytes (that's what Windows uses). */
 176                 sdev->use_192_bytes_for_3f = 1;
 177
 178                 /* Some devices don't like MODE SENSE with page=0x3f,
 179                  * which is the command used for checking if a device
 180                  * is write-protected.  Now that we tell the sd driver
 181                  * to do a 192-byte transfer with this command the
 182                  * majority of devices work fine, but a few still can't
 183                  * handle it.  The sd driver will simply assume those
 184                  * devices are write-enabled. */
 185                 if (us->fflags & US_FL_NO_WP_DETECT)
 186                         sdev->skip_ms_page_3f = 1;
 187
 188                 /* A number of devices have problems with MODE SENSE for
 189                  * page x08, so we will skip it. */
 190                 sdev->skip_ms_page_8 = 1;
 191
 192                 /* Some devices don't handle VPD pages correctly */
 193                 sdev->skip_vpd_pages = 1;
 194
 195                 /* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
 196                 sdev->no_report_opcodes = 1;
 197
 198                 /* Do not attempt to use WRITE SAME */
 199                 sdev->no_write_same = 1;
 200
 201                 /* Some disks return the total number of blocks in response
 202                  * to READ CAPACITY rather than the highest block number.
 203                  * If this device makes that mistake, tell the sd driver. */
 204                 if (us->fflags & US_FL_FIX_CAPACITY)
 205                         sdev->fix_capacity = 1;
 206
 207                 /* A few disks have two indistinguishable version, one of
 208                  * which reports the correct capacity and the other does not.
 209                  * The sd driver has to guess which is the case. */
 210                 if (us->fflags & US_FL_CAPACITY_HEURISTICS)
 211                         sdev->guess_capacity = 1;
 212
 213                 /* Some devices cannot handle READ_CAPACITY_16 */
 214                 if (us->fflags & US_FL_NO_READ_CAPACITY_16)
 215                         sdev->no_read_capacity_16 = 1;
 216
 217                 /*
 218                  * Many devices do not respond properly to READ_CAPACITY_16.
 219                  * Tell the SCSI layer to try READ_CAPACITY_10 first.
 220                  * However some USB 3.0 drive enclosures return capacity
 221                  * modulo 2TB. Those must use READ_CAPACITY_16
 222                  */
 223                 if (!(us->fflags & US_FL_NEEDS_CAP16))
 224                         sdev->try_rc_10_first = 1;
 225
 226                 /* assume SPC3 or latter devices support sense size > 18 */
 227                 if (sdev->scsi_level > SCSI_SPC_2)
 228                         us->fflags |= US_FL_SANE_SENSE;
 229
 230                 /* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
 231                  * Hardware Error) when any low-level error occurs,
 232                  * recoverable or not.  Setting this flag tells the SCSI
 233                  * midlayer to retry such commands, which frequently will
 234                  * succeed and fix the error.  The worst this can lead to
 235                  * is an occasional series of retries that will all fail. */
 236                 sdev->retry_hwerror = 1;
 237
 238                 /* USB disks should allow restart.  Some drives spin down
 239                  * automatically, requiring a START-STOP UNIT command. */
 240                 sdev->allow_restart = 1;
 241
 242                 /* Some USB cardreaders have trouble reading an sdcard's last
 243                  * sector in a larger then 1 sector read, since the performance
 244                  * impact is negligible we set this flag for all USB disks */
 245                 sdev->last_sector_bug = 1;
 246
 247                 /* Enable last-sector hacks for single-target devices using
 248                  * the Bulk-only transport, unless we already know the
 249                  * capacity will be decremented or is correct. */
 250                 if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
 251                                         US_FL_SCM_MULT_TARG)) &&
 252                                 us->protocol == USB_PR_BULK)
 253                         us->use_last_sector_hacks = 1;
 254
 255                 /* Check if write cache default on flag is set or not */
 256                 if (us->fflags & US_FL_WRITE_CACHE)
 257                         sdev->wce_default_on = 1;
 258
 259                 /* A few buggy USB-ATA bridges don't understand FUA */
 260                 if (us->fflags & US_FL_BROKEN_FUA)
 261                         sdev->broken_fua = 1;
 262
 263         } else {
 264
 265                 /* Non-disk-type devices don't need to blacklist any pages
 266                  * or to force 192-byte transfer lengths for MODE SENSE.
 267                  * But they do need to use MODE SENSE(10). */
 268                 sdev->use_10_for_ms = 1;
 269
 270                 /* Some (fake) usb cdrom devices don't like READ_DISC_INFO */
 271                 if (us->fflags & US_FL_NO_READ_DISC_INFO)
 272                         sdev->no_read_disc_info = 1;
 273         }
 274
 275         /* The CB and CBI transports have no way to pass LUN values
 276          * other than the bits in the second byte of a CDB.  But those
 277          * bits don't get set to the LUN value if the device reports
 278          * scsi_level == 0 (UNKNOWN).  Hence such devices must necessarily
 279          * be single-LUN.
 280          */
 281         if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
 282                         sdev->scsi_level == SCSI_UNKNOWN)
 283                 us->max_lun = 0;
 284
 285         /* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
 286          * REMOVAL command, so suppress those commands. */
 287         if (us->fflags & US_FL_NOT_LOCKABLE)
 288                 sdev->lockable = 0;
 289
 290         /* this is to satisfy the compiler, tho I don't think the
 291          * return code is ever checked anywhere. */
 292         return 0;
 293 }
 294
 295 static int target_alloc(struct scsi_target *starget)
 296 {
 297         struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
 298
 299         /*
 300          * Some USB drives don't support REPORT LUNS, even though they
 301          * report a SCSI revision level above 2.  Tell the SCSI layer
 302          * not to issue that command; it will perform a normal sequential
 303          * scan instead.
 304          */
 305         starget->no_report_luns = 1;
 306
 307         /*
 308          * The UFI spec treats the Peripheral Qualifier bits in an
 309          * INQUIRY result as reserved and requires devices to set them
 310          * to 0.  However the SCSI spec requires these bits to be set
 311          * to 3 to indicate when a LUN is not present.
 312          *
 313          * Let the scanning code know if this target merely sets
 314          * Peripheral Device Type to 0x1f to indicate no LUN.
 315          */
 316         if (us->subclass == USB_SC_UFI)
 317                 starget->pdt_1f_for_no_lun = 1;
 318
 319         return 0;
 320 }
 321
 322 /* queue a command */
 323 /* This is always called with scsi_lock(host) held */
 324 static int queuecommand_lck(struct scsi_cmnd *srb,
 325                         void (*done)(struct scsi_cmnd *))
 326 {
 327         struct us_data *us = host_to_us(srb->device->host);
 328
 329         /* check for state-transition errors */
 330         if (us->srb != NULL) {
 331                 printk(KERN_ERR USB_STORAGE "Error in %s: us->srb = %p\n",
 332                         __func__, us->srb);
 333                 return SCSI_MLQUEUE_HOST_BUSY;
 334         }
 335
 336         /* fail the command if we are disconnecting */
 337         if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 338                 usb_stor_dbg(us, "Fail command during disconnect\n");
 339                 srb->result = DID_NO_CONNECT << 16;
 340                 done(srb);
 341                 return 0;
 342         }
 343
 344         /* enqueue the command and wake up the control thread */
 345         srb->scsi_done = done;
 346         us->srb = srb;
 347         complete(&us->cmnd_ready);
 348
 349         return 0;
 350 }
 351
 352 static DEF_SCSI_QCMD(queuecommand)
 353
 354 /***********************************************************************
 355  * Error handling functions
 356  ***********************************************************************/
 357
 358 /* Command timeout and abort */
 359 static int command_abort(struct scsi_cmnd *srb)
 360 {
 361         struct us_data *us = host_to_us(srb->device->host);
 362
 363         usb_stor_dbg(us, "%s called\n", __func__);
 364
 365         /* us->srb together with the TIMED_OUT, RESETTING, and ABORTING
 366          * bits are protected by the host lock. */
 367         scsi_lock(us_to_host(us));
 368
 369         /* Is this command still active? */
 370         if (us->srb != srb) {
 371                 scsi_unlock(us_to_host(us));
 372                 usb_stor_dbg(us, "-- nothing to abort\n");
 373                 return FAILED;
 374         }
 375
 376         /* Set the TIMED_OUT bit.  Also set the ABORTING bit, but only if
 377          * a device reset isn't already in progress (to avoid interfering
 378          * with the reset).  Note that we must retain the host lock while
 379          * calling usb_stor_stop_transport(); otherwise it might interfere
 380          * with an auto-reset that begins as soon as we release the lock. */
 381         set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
 382         if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
 383                 set_bit(US_FLIDX_ABORTING, &us->dflags);
 384                 usb_stor_stop_transport(us);
 385         }
 386         scsi_unlock(us_to_host(us));
 387
 388         /* Wait for the aborted command to finish */
 389         wait_for_completion(&us->notify);
 390         return SUCCESS;
 391 }
 392
 393 /* This invokes the transport reset mechanism to reset the state of the
 394  * device */
 395 static int device_reset(struct scsi_cmnd *srb)
 396 {
 397         struct us_data *us = host_to_us(srb->device->host);
 398         int result;
 399
 400         usb_stor_dbg(us, "%s called\n", __func__);
 401
 402         /* lock the device pointers and do the reset */
 403         mutex_lock(&(us->dev_mutex));
 404         result = us->transport_reset(us);
 405         mutex_unlock(&us->dev_mutex);
 406
 407         return result < 0 ? FAILED : SUCCESS;
 408 }
 409
 410 /* Simulate a SCSI bus reset by resetting the device's USB port. */
 411 static int bus_reset(struct scsi_cmnd *srb)
 412 {
 413         struct us_data *us = host_to_us(srb->device->host);
 414         int result;
 415
 416         usb_stor_dbg(us, "%s called\n", __func__);
 417
 418         result = usb_stor_port_reset(us);
 419         return result < 0 ? FAILED : SUCCESS;
 420 }
 421
 422 /* Report a driver-initiated device reset to the SCSI layer.
 423  * Calling this for a SCSI-initiated reset is unnecessary but harmless.
 424  * The caller must own the SCSI host lock. */
 425 void usb_stor_report_device_reset(struct us_data *us)
 426 {
 427         int i;
 428         struct Scsi_Host *host = us_to_host(us);
 429
 430         scsi_report_device_reset(host, 0, 0);
 431         if (us->fflags & US_FL_SCM_MULT_TARG) {
 432                 for (i = 1; i < host->max_id; ++i)
 433                         scsi_report_device_reset(host, 0, i);
 434         }
 435 }
 436
 437 /* Report a driver-initiated bus reset to the SCSI layer.
 438  * Calling this for a SCSI-initiated reset is unnecessary but harmless.
 439  * The caller must not own the SCSI host lock. */
 440 void usb_stor_report_bus_reset(struct us_data *us)
 441 {
 442         struct Scsi_Host *host = us_to_host(us);
 443
 444         scsi_lock(host);
 445         scsi_report_bus_reset(host, 0);
 446         scsi_unlock(host);
 447 }
 448
 449 /***********************************************************************
 450  * /proc/scsi/ functions
 451  ***********************************************************************/
 452
 453 static int write_info(struct Scsi_Host *host, char *buffer, int length)
 454 {
 455         /* if someone is sending us data, just throw it away */
 456         return length;
 457 }
 458
 459 static int show_info (struct seq_file *m, struct Scsi_Host *host)
 460 {
 461         struct us_data *us = host_to_us(host);
 462         const char *string;
 463
 464         /* print the controller name */
 465         seq_printf(m, "   Host scsi%d: usb-storage\n", host->host_no);
 466
 467         /* print product, vendor, and serial number strings */
 468         if (us->pusb_dev->manufacturer)
 469                 string = us->pusb_dev->manufacturer;
 470         else if (us->unusual_dev->vendorName)
 471                 string = us->unusual_dev->vendorName;
 472         else
 473                 string = "Unknown";
 474         seq_printf(m, "       Vendor: %s\n", string);
 475         if (us->pusb_dev->product)
 476                 string = us->pusb_dev->product;
 477         else if (us->unusual_dev->productName)
 478                 string = us->unusual_dev->productName;
 479         else
 480                 string = "Unknown";
 481         seq_printf(m, "      Product: %s\n", string);
 482         if (us->pusb_dev->serial)
 483                 string = us->pusb_dev->serial;
 484         else
 485                 string = "None";
 486         seq_printf(m, "Serial Number: %s\n", string);
 487
 488         /* show the protocol and transport */
 489         seq_printf(m, "     Protocol: %s\n", us->protocol_name);
 490         seq_printf(m, "    Transport: %s\n", us->transport_name);
 491
 492         /* show the device flags */
 493         seq_printf(m, "       Quirks:");
 494
 495 #define US_FLAG(name, value) \
 496         if (us->fflags & value) seq_printf(m, " " #name);
 497 US_DO_ALL_FLAGS
 498 #undef US_FLAG
 499         seq_putc(m, '\n');
 500         return 0;
 501 }
 502
 503 /***********************************************************************
 504  * Sysfs interface
 505  ***********************************************************************/
 506
 507 /* Output routine for the sysfs max_sectors file */
 508 static ssize_t max_sectors_show(struct device *dev, struct device_attribute *attr, char *buf)
 509 {
 510         struct scsi_device *sdev = to_scsi_device(dev);
 511
 512         return sprintf(buf, "%u\n", queue_max_hw_sectors(sdev->request_queue));
 513 }
 514
 515 /* Input routine for the sysfs max_sectors file */
 516 static ssize_t max_sectors_store(struct device *dev, struct device_attribute *attr, const char *buf,
 517                 size_t count)
 518 {
 519         struct scsi_device *sdev = to_scsi_device(dev);
 520         unsigned short ms;
 521
 522         if (sscanf(buf, "%hu", &ms) > 0) {
 523                 blk_queue_max_hw_sectors(sdev->request_queue, ms);
 524                 return count;
 525         }
 526         return -EINVAL;
 527 }
 528 static DEVICE_ATTR_RW(max_sectors);
 529
 530 static struct device_attribute *sysfs_device_attr_list[] = {
 531         &dev_attr_max_sectors,
 532         NULL,
 533 };
 534
 535 /*
 536  * this defines our host template, with which we'll allocate hosts
 537  */
 538
 539 static const struct scsi_host_template usb_stor_host_template = {
 540         /* basic userland interface stuff */
 541         .name =                         "usb-storage",
 542         .proc_name =                    "usb-storage",
 543         .show_info =                    show_info,
 544         .write_info =                   write_info,
 545         .info =                         host_info,
 546
 547         /* command interface -- queued only */
 548         .queuecommand =                 queuecommand,
 549
 550         /* error and abort handlers */
 551         .eh_abort_handler =             command_abort,
 552         .eh_device_reset_handler =      device_reset,
 553         .eh_bus_reset_handler =         bus_reset,
 554
 555         /* queue commands only, only one command per LUN */
 556         .can_queue =                    1,
 557
 558         /* unknown initiator id */
 559         .this_id =                      -1,
 560
 561         .slave_alloc =                  slave_alloc,
 562         .slave_configure =              slave_configure,
 563         .target_alloc =                 target_alloc,
 564
 565         /* lots of sg segments can be handled */
 566         .sg_tablesize =                 SCSI_MAX_SG_CHAIN_SEGMENTS,
 567
 568         /* limit the total size of a transfer to 120 KB */
 569         .max_sectors =                  240,
 570
 571         /* merge commands... this seems to help performance, but
 572          * periodically someone should test to see which setting is more
 573          * optimal.
 574          */
 575         .use_clustering =               1,
 576
 577         /* emulated HBA */
 578         .emulated =                     1,
 579
 580         /* we do our own delay after a device or bus reset */
 581         .skip_settle_delay =            1,
 582
 583         /* sysfs device attributes */
 584         .sdev_attrs =                   sysfs_device_attr_list,
 585
 586         /* module management */
 587         .module =                       THIS_MODULE
 588 };
 589
 590 void usb_stor_host_template_init(struct scsi_host_template *sht,
 591                                  const char *name, struct module *owner)
 592 {
 593         *sht = usb_stor_host_template;
 594         sht->name = name;
 595         sht->proc_name = name;
 596         sht->module = owner;
 597 }
 598 EXPORT_SYMBOL_GPL(usb_stor_host_template_init);
 599
 600 /* To Report "Illegal Request: Invalid Field in CDB */
 601 unsigned char usb_stor_sense_invalidCDB[18] = {
 602         [0]     = 0x70,                     /* current error */
 603         [2]     = ILLEGAL_REQUEST,          /* Illegal Request = 0x05 */
 604         [7]     = 0x0a,                     /* additional length */
 605         [12]    = 0x24                      /* Invalid Field in CDB */
 606 };
 607 EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);