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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for USB Mass Storage compliant devices
4 * SCSI layer glue code
5 *
6 * Current development and maintenance by:
7 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
8 *
9 * Developed with the assistance of:
10 * (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
11 * (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
12 *
13 * Initial work by:
14 * (c) 1999 Michael Gee (michael@linuxspecific.com)
15 *
16 * This driver is based on the 'USB Mass Storage Class' document. This
17 * describes in detail the protocol used to communicate with such
18 * devices. Clearly, the designers had SCSI and ATAPI commands in
19 * mind when they created this document. The commands are all very
20 * similar to commands in the SCSI-II and ATAPI specifications.
21 *
22 * It is important to note that in a number of cases this class
23 * exhibits class-specific exemptions from the USB specification.
24 * Notably the usage of NAK, STALL and ACK differs from the norm, in
25 * that they are used to communicate wait, failed and OK on commands.
26 *
27 * Also, for certain devices, the interrupt endpoint is used to convey
28 * status of a command.
29 */
30
31#include <linux/blkdev.h>
32#include <linux/dma-mapping.h>
33#include <linux/module.h>
34#include <linux/mutex.h>
35
36#include <scsi/scsi.h>
37#include <scsi/scsi_cmnd.h>
38#include <scsi/scsi_devinfo.h>
39#include <scsi/scsi_device.h>
40#include <scsi/scsi_eh.h>
41
42#include "usb.h"
43#include "scsiglue.h"
44#include "debug.h"
45#include "transport.h"
46#include "protocol.h"
47
48/*
49 * Vendor IDs for companies that seem to include the READ CAPACITY bug
50 * in all their devices
51 */
52#define VENDOR_ID_NOKIA 0x0421
53#define VENDOR_ID_NIKON 0x04b0
54#define VENDOR_ID_PENTAX 0x0a17
55#define VENDOR_ID_MOTOROLA 0x22b8
56
57/***********************************************************************
58 * Host functions
59 ***********************************************************************/
60
61static const char* host_info(struct Scsi_Host *host)
62{
63 struct us_data *us = host_to_us(host);
64 return us->scsi_name;
65}
66
67static int slave_alloc (struct scsi_device *sdev)
68{
69 struct us_data *us = host_to_us(sdev->host);
70
71 /*
72 * Set the INQUIRY transfer length to 36. We don't use any of
73 * the extra data and many devices choke if asked for more or
74 * less than 36 bytes.
75 */
76 sdev->inquiry_len = 36;
77
78 /* Tell the SCSI layer if we know there is more than one LUN */
79 if (us->protocol == USB_PR_BULK && us->max_lun > 0)
80 sdev->sdev_bflags |= BLIST_FORCELUN;
81
82 /*
83 * Some USB storage devices reset if the IO advice hints grouping mode
84 * page is queried. Hence skip that mode page.
85 */
86 sdev->sdev_bflags |= BLIST_SKIP_IO_HINTS;
87
88 return 0;
89}
90
91static int device_configure(struct scsi_device *sdev, struct queue_limits *lim)
92{
93 struct us_data *us = host_to_us(sdev->host);
94 struct device *dev = us->pusb_dev->bus->sysdev;
95
96 /*
97 * Many devices have trouble transferring more than 32KB at a time,
98 * while others have trouble with more than 64K. At this time we
99 * are limiting both to 32K (64 sectores).
100 */
101 if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
102 unsigned int max_sectors = 64;
103
104 if (us->fflags & US_FL_MAX_SECTORS_MIN)
105 max_sectors = PAGE_SIZE >> 9;
106 lim->max_hw_sectors = min(lim->max_hw_sectors, max_sectors);
107 } else if (sdev->type == TYPE_TAPE) {
108 /*
109 * Tapes need much higher max_sector limits, so just
110 * raise it to the maximum possible (4 GB / 512) and
111 * let the queue segment size sort out the real limit.
112 */
113 lim->max_hw_sectors = 0x7FFFFF;
114 } else if (us->pusb_dev->speed >= USB_SPEED_SUPER) {
115 /*
116 * USB3 devices will be limited to 2048 sectors. This gives us
117 * better throughput on most devices.
118 */
119 lim->max_hw_sectors = 2048;
120 }
121
122 /*
123 * The max_hw_sectors should be up to maximum size of a mapping for
124 * the device. Otherwise, a DMA API might fail on swiotlb environment.
125 */
126 lim->max_hw_sectors = min_t(size_t,
127 lim->max_hw_sectors, dma_max_mapping_size(dev) >> SECTOR_SHIFT);
128
129 /*
130 * We can't put these settings in slave_alloc() because that gets
131 * called before the device type is known. Consequently these
132 * settings can't be overridden via the scsi devinfo mechanism.
133 */
134 if (sdev->type == TYPE_DISK) {
135
136 /*
137 * Some vendors seem to put the READ CAPACITY bug into
138 * all their devices -- primarily makers of cell phones
139 * and digital cameras. Since these devices always use
140 * flash media and can be expected to have an even number
141 * of sectors, we will always enable the CAPACITY_HEURISTICS
142 * flag unless told otherwise.
143 */
144 switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
145 case VENDOR_ID_NOKIA:
146 case VENDOR_ID_NIKON:
147 case VENDOR_ID_PENTAX:
148 case VENDOR_ID_MOTOROLA:
149 if (!(us->fflags & (US_FL_FIX_CAPACITY |
150 US_FL_CAPACITY_OK)))
151 us->fflags |= US_FL_CAPACITY_HEURISTICS;
152 break;
153 }
154
155 /*
156 * Disk-type devices use MODE SENSE(6) if the protocol
157 * (SubClass) is Transparent SCSI, otherwise they use
158 * MODE SENSE(10).
159 */
160 if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
161 sdev->use_10_for_ms = 1;
162
163 /*
164 *Many disks only accept MODE SENSE transfer lengths of
165 * 192 bytes (that's what Windows uses).
166 */
167 sdev->use_192_bytes_for_3f = 1;
168
169 /*
170 * Some devices report generic values until the media has been
171 * accessed. Force a READ(10) prior to querying device
172 * characteristics.
173 */
174 sdev->read_before_ms = 1;
175
176 /*
177 * Some devices don't like MODE SENSE with page=0x3f,
178 * which is the command used for checking if a device
179 * is write-protected. Now that we tell the sd driver
180 * to do a 192-byte transfer with this command the
181 * majority of devices work fine, but a few still can't
182 * handle it. The sd driver will simply assume those
183 * devices are write-enabled.
184 */
185 if (us->fflags & US_FL_NO_WP_DETECT)
186 sdev->skip_ms_page_3f = 1;
187
188 /*
189 * A number of devices have problems with MODE SENSE for
190 * page x08, so we will skip it.
191 */
192 sdev->skip_ms_page_8 = 1;
193
194 /*
195 * Some devices don't handle VPD pages correctly, so skip vpd
196 * pages if not forced by SCSI layer.
197 */
198 sdev->skip_vpd_pages = !sdev->try_vpd_pages;
199
200 /* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
201 sdev->no_report_opcodes = 1;
202
203 /* Do not attempt to use WRITE SAME */
204 sdev->no_write_same = 1;
205
206 /*
207 * Some disks return the total number of blocks in response
208 * to READ CAPACITY rather than the highest block number.
209 * If this device makes that mistake, tell the sd driver.
210 */
211 if (us->fflags & US_FL_FIX_CAPACITY)
212 sdev->fix_capacity = 1;
213
214 /*
215 * A few disks have two indistinguishable version, one of
216 * which reports the correct capacity and the other does not.
217 * The sd driver has to guess which is the case.
218 */
219 if (us->fflags & US_FL_CAPACITY_HEURISTICS)
220 sdev->guess_capacity = 1;
221
222 /* Some devices cannot handle READ_CAPACITY_16 */
223 if (us->fflags & US_FL_NO_READ_CAPACITY_16)
224 sdev->no_read_capacity_16 = 1;
225
226 /*
227 * Many devices do not respond properly to READ_CAPACITY_16.
228 * Tell the SCSI layer to try READ_CAPACITY_10 first.
229 * However some USB 3.0 drive enclosures return capacity
230 * modulo 2TB. Those must use READ_CAPACITY_16
231 */
232 if (!(us->fflags & US_FL_NEEDS_CAP16))
233 sdev->try_rc_10_first = 1;
234
235 /*
236 * assume SPC3 or latter devices support sense size > 18
237 * unless US_FL_BAD_SENSE quirk is specified.
238 */
239 if (sdev->scsi_level > SCSI_SPC_2 &&
240 !(us->fflags & US_FL_BAD_SENSE))
241 us->fflags |= US_FL_SANE_SENSE;
242
243 /*
244 * USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
245 * Hardware Error) when any low-level error occurs,
246 * recoverable or not. Setting this flag tells the SCSI
247 * midlayer to retry such commands, which frequently will
248 * succeed and fix the error. The worst this can lead to
249 * is an occasional series of retries that will all fail.
250 */
251 sdev->retry_hwerror = 1;
252
253 /*
254 * USB disks should allow restart. Some drives spin down
255 * automatically, requiring a START-STOP UNIT command.
256 */
257 sdev->allow_restart = 1;
258
259 /*
260 * Some USB cardreaders have trouble reading an sdcard's last
261 * sector in a larger then 1 sector read, since the performance
262 * impact is negligible we set this flag for all USB disks
263 */
264 sdev->last_sector_bug = 1;
265
266 /*
267 * Enable last-sector hacks for single-target devices using
268 * the Bulk-only transport, unless we already know the
269 * capacity will be decremented or is correct.
270 */
271 if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
272 US_FL_SCM_MULT_TARG)) &&
273 us->protocol == USB_PR_BULK)
274 us->use_last_sector_hacks = 1;
275
276 /* Check if write cache default on flag is set or not */
277 if (us->fflags & US_FL_WRITE_CACHE)
278 sdev->wce_default_on = 1;
279
280 /* A few buggy USB-ATA bridges don't understand FUA */
281 if (us->fflags & US_FL_BROKEN_FUA)
282 sdev->broken_fua = 1;
283
284 /* Some even totally fail to indicate a cache */
285 if (us->fflags & US_FL_ALWAYS_SYNC) {
286 /* don't read caching information */
287 sdev->skip_ms_page_8 = 1;
288 sdev->skip_ms_page_3f = 1;
289 /* assume sync is needed */
290 sdev->wce_default_on = 1;
291 }
292 } else {
293
294 /*
295 * Non-disk-type devices don't need to ignore any pages
296 * or to force 192-byte transfer lengths for MODE SENSE.
297 * But they do need to use MODE SENSE(10).
298 */
299 sdev->use_10_for_ms = 1;
300
301 /* Some (fake) usb cdrom devices don't like READ_DISC_INFO */
302 if (us->fflags & US_FL_NO_READ_DISC_INFO)
303 sdev->no_read_disc_info = 1;
304 }
305
306 /*
307 * The CB and CBI transports have no way to pass LUN values
308 * other than the bits in the second byte of a CDB. But those
309 * bits don't get set to the LUN value if the device reports
310 * scsi_level == 0 (UNKNOWN). Hence such devices must necessarily
311 * be single-LUN.
312 */
313 if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
314 sdev->scsi_level == SCSI_UNKNOWN)
315 us->max_lun = 0;
316
317 /*
318 * Some devices choke when they receive a PREVENT-ALLOW MEDIUM
319 * REMOVAL command, so suppress those commands.
320 */
321 if (us->fflags & US_FL_NOT_LOCKABLE)
322 sdev->lockable = 0;
323
324 /*
325 * this is to satisfy the compiler, tho I don't think the
326 * return code is ever checked anywhere.
327 */
328 return 0;
329}
330
331static int target_alloc(struct scsi_target *starget)
332{
333 struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
334
335 /*
336 * Some USB drives don't support REPORT LUNS, even though they
337 * report a SCSI revision level above 2. Tell the SCSI layer
338 * not to issue that command; it will perform a normal sequential
339 * scan instead.
340 */
341 starget->no_report_luns = 1;
342
343 /*
344 * The UFI spec treats the Peripheral Qualifier bits in an
345 * INQUIRY result as reserved and requires devices to set them
346 * to 0. However the SCSI spec requires these bits to be set
347 * to 3 to indicate when a LUN is not present.
348 *
349 * Let the scanning code know if this target merely sets
350 * Peripheral Device Type to 0x1f to indicate no LUN.
351 */
352 if (us->subclass == USB_SC_UFI)
353 starget->pdt_1f_for_no_lun = 1;
354
355 return 0;
356}
357
358/* queue a command */
359/* This is always called with scsi_lock(host) held */
360static int queuecommand_lck(struct scsi_cmnd *srb)
361{
362 void (*done)(struct scsi_cmnd *) = scsi_done;
363 struct us_data *us = host_to_us(srb->device->host);
364
365 /* check for state-transition errors */
366 if (us->srb != NULL) {
367 dev_err(&us->pusb_intf->dev,
368 "Error in %s: us->srb = %p\n", __func__, us->srb);
369 return SCSI_MLQUEUE_HOST_BUSY;
370 }
371
372 /* fail the command if we are disconnecting */
373 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
374 usb_stor_dbg(us, "Fail command during disconnect\n");
375 srb->result = DID_NO_CONNECT << 16;
376 done(srb);
377 return 0;
378 }
379
380 if ((us->fflags & US_FL_NO_ATA_1X) &&
381 (srb->cmnd[0] == ATA_12 || srb->cmnd[0] == ATA_16)) {
382 memcpy(srb->sense_buffer, usb_stor_sense_invalidCDB,
383 sizeof(usb_stor_sense_invalidCDB));
384 srb->result = SAM_STAT_CHECK_CONDITION;
385 done(srb);
386 return 0;
387 }
388
389 /* enqueue the command and wake up the control thread */
390 us->srb = srb;
391 complete(&us->cmnd_ready);
392
393 return 0;
394}
395
396static DEF_SCSI_QCMD(queuecommand)
397
398/***********************************************************************
399 * Error handling functions
400 ***********************************************************************/
401
402/* Command timeout and abort */
403static int command_abort_matching(struct us_data *us, struct scsi_cmnd *srb_match)
404{
405 /*
406 * us->srb together with the TIMED_OUT, RESETTING, and ABORTING
407 * bits are protected by the host lock.
408 */
409 scsi_lock(us_to_host(us));
410
411 /* is there any active pending command to abort ? */
412 if (!us->srb) {
413 scsi_unlock(us_to_host(us));
414 usb_stor_dbg(us, "-- nothing to abort\n");
415 return SUCCESS;
416 }
417
418 /* Does the command match the passed srb if any ? */
419 if (srb_match && us->srb != srb_match) {
420 scsi_unlock(us_to_host(us));
421 usb_stor_dbg(us, "-- pending command mismatch\n");
422 return FAILED;
423 }
424
425 /*
426 * Set the TIMED_OUT bit. Also set the ABORTING bit, but only if
427 * a device reset isn't already in progress (to avoid interfering
428 * with the reset). Note that we must retain the host lock while
429 * calling usb_stor_stop_transport(); otherwise it might interfere
430 * with an auto-reset that begins as soon as we release the lock.
431 */
432 set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
433 if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
434 set_bit(US_FLIDX_ABORTING, &us->dflags);
435 usb_stor_stop_transport(us);
436 }
437 scsi_unlock(us_to_host(us));
438
439 /* Wait for the aborted command to finish */
440 wait_for_completion(&us->notify);
441 return SUCCESS;
442}
443
444static int command_abort(struct scsi_cmnd *srb)
445{
446 struct us_data *us = host_to_us(srb->device->host);
447
448 usb_stor_dbg(us, "%s called\n", __func__);
449 return command_abort_matching(us, srb);
450}
451
452/*
453 * This invokes the transport reset mechanism to reset the state of the
454 * device
455 */
456static int device_reset(struct scsi_cmnd *srb)
457{
458 struct us_data *us = host_to_us(srb->device->host);
459 int result;
460
461 usb_stor_dbg(us, "%s called\n", __func__);
462
463 /* abort any pending command before reset */
464 command_abort_matching(us, NULL);
465
466 /* lock the device pointers and do the reset */
467 mutex_lock(&(us->dev_mutex));
468 result = us->transport_reset(us);
469 mutex_unlock(&us->dev_mutex);
470
471 return result < 0 ? FAILED : SUCCESS;
472}
473
474/* Simulate a SCSI bus reset by resetting the device's USB port. */
475static int bus_reset(struct scsi_cmnd *srb)
476{
477 struct us_data *us = host_to_us(srb->device->host);
478 int result;
479
480 usb_stor_dbg(us, "%s called\n", __func__);
481
482 result = usb_stor_port_reset(us);
483 return result < 0 ? FAILED : SUCCESS;
484}
485
486/*
487 * Report a driver-initiated device reset to the SCSI layer.
488 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
489 * The caller must own the SCSI host lock.
490 */
491void usb_stor_report_device_reset(struct us_data *us)
492{
493 int i;
494 struct Scsi_Host *host = us_to_host(us);
495
496 scsi_report_device_reset(host, 0, 0);
497 if (us->fflags & US_FL_SCM_MULT_TARG) {
498 for (i = 1; i < host->max_id; ++i)
499 scsi_report_device_reset(host, 0, i);
500 }
501}
502
503/*
504 * Report a driver-initiated bus reset to the SCSI layer.
505 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
506 * The caller must not own the SCSI host lock.
507 */
508void usb_stor_report_bus_reset(struct us_data *us)
509{
510 struct Scsi_Host *host = us_to_host(us);
511
512 scsi_lock(host);
513 scsi_report_bus_reset(host, 0);
514 scsi_unlock(host);
515}
516
517/***********************************************************************
518 * /proc/scsi/ functions
519 ***********************************************************************/
520
521static int write_info(struct Scsi_Host *host, char *buffer, int length)
522{
523 /* if someone is sending us data, just throw it away */
524 return length;
525}
526
527static int show_info (struct seq_file *m, struct Scsi_Host *host)
528{
529 struct us_data *us = host_to_us(host);
530 const char *string;
531
532 /* print the controller name */
533 seq_printf(m, " Host scsi%d: usb-storage\n", host->host_no);
534
535 /* print product, vendor, and serial number strings */
536 if (us->pusb_dev->manufacturer)
537 string = us->pusb_dev->manufacturer;
538 else if (us->unusual_dev->vendorName)
539 string = us->unusual_dev->vendorName;
540 else
541 string = "Unknown";
542 seq_printf(m, " Vendor: %s\n", string);
543 if (us->pusb_dev->product)
544 string = us->pusb_dev->product;
545 else if (us->unusual_dev->productName)
546 string = us->unusual_dev->productName;
547 else
548 string = "Unknown";
549 seq_printf(m, " Product: %s\n", string);
550 if (us->pusb_dev->serial)
551 string = us->pusb_dev->serial;
552 else
553 string = "None";
554 seq_printf(m, "Serial Number: %s\n", string);
555
556 /* show the protocol and transport */
557 seq_printf(m, " Protocol: %s\n", us->protocol_name);
558 seq_printf(m, " Transport: %s\n", us->transport_name);
559
560 /* show the device flags */
561 seq_printf(m, " Quirks:");
562
563#define US_FLAG(name, value) \
564 if (us->fflags & value) seq_printf(m, " " #name);
565US_DO_ALL_FLAGS
566#undef US_FLAG
567 seq_putc(m, '\n');
568 return 0;
569}
570
571/***********************************************************************
572 * Sysfs interface
573 ***********************************************************************/
574
575/* Output routine for the sysfs max_sectors file */
576static ssize_t max_sectors_show(struct device *dev, struct device_attribute *attr, char *buf)
577{
578 struct scsi_device *sdev = to_scsi_device(dev);
579
580 return sprintf(buf, "%u\n", queue_max_hw_sectors(sdev->request_queue));
581}
582
583/* Input routine for the sysfs max_sectors file */
584static ssize_t max_sectors_store(struct device *dev, struct device_attribute *attr, const char *buf,
585 size_t count)
586{
587 struct scsi_device *sdev = to_scsi_device(dev);
588 struct queue_limits lim;
589 unsigned short ms;
590 int ret;
591
592 if (sscanf(buf, "%hu", &ms) <= 0)
593 return -EINVAL;
594
595 blk_mq_freeze_queue(sdev->request_queue);
596 lim = queue_limits_start_update(sdev->request_queue);
597 lim.max_hw_sectors = ms;
598 ret = queue_limits_commit_update(sdev->request_queue, &lim);
599 blk_mq_unfreeze_queue(sdev->request_queue);
600
601 if (ret)
602 return ret;
603 return count;
604}
605static DEVICE_ATTR_RW(max_sectors);
606
607static struct attribute *usb_sdev_attrs[] = {
608 &dev_attr_max_sectors.attr,
609 NULL,
610};
611
612ATTRIBUTE_GROUPS(usb_sdev);
613
614/*
615 * this defines our host template, with which we'll allocate hosts
616 */
617
618static const struct scsi_host_template usb_stor_host_template = {
619 /* basic userland interface stuff */
620 .name = "usb-storage",
621 .proc_name = "usb-storage",
622 .show_info = show_info,
623 .write_info = write_info,
624 .info = host_info,
625
626 /* command interface -- queued only */
627 .queuecommand = queuecommand,
628
629 /* error and abort handlers */
630 .eh_abort_handler = command_abort,
631 .eh_device_reset_handler = device_reset,
632 .eh_bus_reset_handler = bus_reset,
633
634 /* queue commands only, only one command per LUN */
635 .can_queue = 1,
636
637 /* unknown initiator id */
638 .this_id = -1,
639
640 .slave_alloc = slave_alloc,
641 .device_configure = device_configure,
642 .target_alloc = target_alloc,
643
644 /* lots of sg segments can be handled */
645 .sg_tablesize = SG_MAX_SEGMENTS,
646
647 /*
648 * Some host controllers may have alignment requirements.
649 * We'll play it safe by requiring 512-byte alignment always.
650 */
651 .dma_alignment = 511,
652
653 /*
654 * Limit the total size of a transfer to 120 KB.
655 *
656 * Some devices are known to choke with anything larger. It seems like
657 * the problem stems from the fact that original IDE controllers had
658 * only an 8-bit register to hold the number of sectors in one transfer
659 * and even those couldn't handle a full 256 sectors.
660 *
661 * Because we want to make sure we interoperate with as many devices as
662 * possible, we will maintain a 240 sector transfer size limit for USB
663 * Mass Storage devices.
664 *
665 * Tests show that other operating have similar limits with Microsoft
666 * Windows 7 limiting transfers to 128 sectors for both USB2 and USB3
667 * and Apple Mac OS X 10.11 limiting transfers to 256 sectors for USB2
668 * and 2048 for USB3 devices.
669 */
670 .max_sectors = 240,
671
672 /* emulated HBA */
673 .emulated = 1,
674
675 /* we do our own delay after a device or bus reset */
676 .skip_settle_delay = 1,
677
678 /* sysfs device attributes */
679 .sdev_groups = usb_sdev_groups,
680
681 /* module management */
682 .module = THIS_MODULE
683};
684
685void usb_stor_host_template_init(struct scsi_host_template *sht,
686 const char *name, struct module *owner)
687{
688 *sht = usb_stor_host_template;
689 sht->name = name;
690 sht->proc_name = name;
691 sht->module = owner;
692}
693EXPORT_SYMBOL_GPL(usb_stor_host_template_init);
694
695/* To Report "Illegal Request: Invalid Field in CDB */
696unsigned char usb_stor_sense_invalidCDB[18] = {
697 [0] = 0x70, /* current error */
698 [2] = ILLEGAL_REQUEST, /* Illegal Request = 0x05 */
699 [7] = 0x0a, /* additional length */
700 [12] = 0x24 /* Invalid Field in CDB */
701};
702EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for USB Mass Storage compliant devices
4 * SCSI layer glue code
5 *
6 * Current development and maintenance by:
7 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
8 *
9 * Developed with the assistance of:
10 * (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
11 * (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
12 *
13 * Initial work by:
14 * (c) 1999 Michael Gee (michael@linuxspecific.com)
15 *
16 * This driver is based on the 'USB Mass Storage Class' document. This
17 * describes in detail the protocol used to communicate with such
18 * devices. Clearly, the designers had SCSI and ATAPI commands in
19 * mind when they created this document. The commands are all very
20 * similar to commands in the SCSI-II and ATAPI specifications.
21 *
22 * It is important to note that in a number of cases this class
23 * exhibits class-specific exemptions from the USB specification.
24 * Notably the usage of NAK, STALL and ACK differs from the norm, in
25 * that they are used to communicate wait, failed and OK on commands.
26 *
27 * Also, for certain devices, the interrupt endpoint is used to convey
28 * status of a command.
29 */
30
31#include <linux/blkdev.h>
32#include <linux/dma-mapping.h>
33#include <linux/module.h>
34#include <linux/mutex.h>
35
36#include <scsi/scsi.h>
37#include <scsi/scsi_cmnd.h>
38#include <scsi/scsi_devinfo.h>
39#include <scsi/scsi_device.h>
40#include <scsi/scsi_eh.h>
41
42#include "usb.h"
43#include <linux/usb/hcd.h>
44#include "scsiglue.h"
45#include "debug.h"
46#include "transport.h"
47#include "protocol.h"
48
49/*
50 * Vendor IDs for companies that seem to include the READ CAPACITY bug
51 * in all their devices
52 */
53#define VENDOR_ID_NOKIA 0x0421
54#define VENDOR_ID_NIKON 0x04b0
55#define VENDOR_ID_PENTAX 0x0a17
56#define VENDOR_ID_MOTOROLA 0x22b8
57
58/***********************************************************************
59 * Host functions
60 ***********************************************************************/
61
62static const char* host_info(struct Scsi_Host *host)
63{
64 struct us_data *us = host_to_us(host);
65 return us->scsi_name;
66}
67
68static int slave_alloc (struct scsi_device *sdev)
69{
70 struct us_data *us = host_to_us(sdev->host);
71
72 /*
73 * Set the INQUIRY transfer length to 36. We don't use any of
74 * the extra data and many devices choke if asked for more or
75 * less than 36 bytes.
76 */
77 sdev->inquiry_len = 36;
78
79 /*
80 * Some host controllers may have alignment requirements.
81 * We'll play it safe by requiring 512-byte alignment always.
82 */
83 blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
84
85 /* Tell the SCSI layer if we know there is more than one LUN */
86 if (us->protocol == USB_PR_BULK && us->max_lun > 0)
87 sdev->sdev_bflags |= BLIST_FORCELUN;
88
89 return 0;
90}
91
92static int slave_configure(struct scsi_device *sdev)
93{
94 struct us_data *us = host_to_us(sdev->host);
95 struct device *dev = us->pusb_dev->bus->sysdev;
96
97 /*
98 * Many devices have trouble transferring more than 32KB at a time,
99 * while others have trouble with more than 64K. At this time we
100 * are limiting both to 32K (64 sectores).
101 */
102 if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
103 unsigned int max_sectors = 64;
104
105 if (us->fflags & US_FL_MAX_SECTORS_MIN)
106 max_sectors = PAGE_SIZE >> 9;
107 if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
108 blk_queue_max_hw_sectors(sdev->request_queue,
109 max_sectors);
110 } else if (sdev->type == TYPE_TAPE) {
111 /*
112 * Tapes need much higher max_sector limits, so just
113 * raise it to the maximum possible (4 GB / 512) and
114 * let the queue segment size sort out the real limit.
115 */
116 blk_queue_max_hw_sectors(sdev->request_queue, 0x7FFFFF);
117 } else if (us->pusb_dev->speed >= USB_SPEED_SUPER) {
118 /*
119 * USB3 devices will be limited to 2048 sectors. This gives us
120 * better throughput on most devices.
121 */
122 blk_queue_max_hw_sectors(sdev->request_queue, 2048);
123 }
124
125 /*
126 * The max_hw_sectors should be up to maximum size of a mapping for
127 * the device. Otherwise, a DMA API might fail on swiotlb environment.
128 */
129 blk_queue_max_hw_sectors(sdev->request_queue,
130 min_t(size_t, queue_max_hw_sectors(sdev->request_queue),
131 dma_max_mapping_size(dev) >> SECTOR_SHIFT));
132
133 /*
134 * Some USB host controllers can't do DMA; they have to use PIO.
135 * For such controllers we need to make sure the block layer sets
136 * up bounce buffers in addressable memory.
137 */
138 if (!hcd_uses_dma(bus_to_hcd(us->pusb_dev->bus)) ||
139 (bus_to_hcd(us->pusb_dev->bus)->localmem_pool != NULL))
140 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
141
142 /*
143 * We can't put these settings in slave_alloc() because that gets
144 * called before the device type is known. Consequently these
145 * settings can't be overridden via the scsi devinfo mechanism.
146 */
147 if (sdev->type == TYPE_DISK) {
148
149 /*
150 * Some vendors seem to put the READ CAPACITY bug into
151 * all their devices -- primarily makers of cell phones
152 * and digital cameras. Since these devices always use
153 * flash media and can be expected to have an even number
154 * of sectors, we will always enable the CAPACITY_HEURISTICS
155 * flag unless told otherwise.
156 */
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 /*
169 * Disk-type devices use MODE SENSE(6) if the protocol
170 * (SubClass) is Transparent SCSI, otherwise they use
171 * MODE SENSE(10).
172 */
173 if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
174 sdev->use_10_for_ms = 1;
175
176 /*
177 *Many disks only accept MODE SENSE transfer lengths of
178 * 192 bytes (that's what Windows uses).
179 */
180 sdev->use_192_bytes_for_3f = 1;
181
182 /*
183 * Some devices report generic values until the media has been
184 * accessed. Force a READ(10) prior to querying device
185 * characteristics.
186 */
187 sdev->read_before_ms = 1;
188
189 /*
190 * Some devices don't like MODE SENSE with page=0x3f,
191 * which is the command used for checking if a device
192 * is write-protected. Now that we tell the sd driver
193 * to do a 192-byte transfer with this command the
194 * majority of devices work fine, but a few still can't
195 * handle it. The sd driver will simply assume those
196 * devices are write-enabled.
197 */
198 if (us->fflags & US_FL_NO_WP_DETECT)
199 sdev->skip_ms_page_3f = 1;
200
201 /*
202 * A number of devices have problems with MODE SENSE for
203 * page x08, so we will skip it.
204 */
205 sdev->skip_ms_page_8 = 1;
206
207 /*
208 * Some devices don't handle VPD pages correctly, so skip vpd
209 * pages if not forced by SCSI layer.
210 */
211 sdev->skip_vpd_pages = !sdev->try_vpd_pages;
212
213 /* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
214 sdev->no_report_opcodes = 1;
215
216 /* Do not attempt to use WRITE SAME */
217 sdev->no_write_same = 1;
218
219 /*
220 * Some disks return the total number of blocks in response
221 * to READ CAPACITY rather than the highest block number.
222 * If this device makes that mistake, tell the sd driver.
223 */
224 if (us->fflags & US_FL_FIX_CAPACITY)
225 sdev->fix_capacity = 1;
226
227 /*
228 * A few disks have two indistinguishable version, one of
229 * which reports the correct capacity and the other does not.
230 * The sd driver has to guess which is the case.
231 */
232 if (us->fflags & US_FL_CAPACITY_HEURISTICS)
233 sdev->guess_capacity = 1;
234
235 /* Some devices cannot handle READ_CAPACITY_16 */
236 if (us->fflags & US_FL_NO_READ_CAPACITY_16)
237 sdev->no_read_capacity_16 = 1;
238
239 /*
240 * Many devices do not respond properly to READ_CAPACITY_16.
241 * Tell the SCSI layer to try READ_CAPACITY_10 first.
242 * However some USB 3.0 drive enclosures return capacity
243 * modulo 2TB. Those must use READ_CAPACITY_16
244 */
245 if (!(us->fflags & US_FL_NEEDS_CAP16))
246 sdev->try_rc_10_first = 1;
247
248 /*
249 * assume SPC3 or latter devices support sense size > 18
250 * unless US_FL_BAD_SENSE quirk is specified.
251 */
252 if (sdev->scsi_level > SCSI_SPC_2 &&
253 !(us->fflags & US_FL_BAD_SENSE))
254 us->fflags |= US_FL_SANE_SENSE;
255
256 /*
257 * USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
258 * Hardware Error) when any low-level error occurs,
259 * recoverable or not. Setting this flag tells the SCSI
260 * midlayer to retry such commands, which frequently will
261 * succeed and fix the error. The worst this can lead to
262 * is an occasional series of retries that will all fail.
263 */
264 sdev->retry_hwerror = 1;
265
266 /*
267 * USB disks should allow restart. Some drives spin down
268 * automatically, requiring a START-STOP UNIT command.
269 */
270 sdev->allow_restart = 1;
271
272 /*
273 * Some USB cardreaders have trouble reading an sdcard's last
274 * sector in a larger then 1 sector read, since the performance
275 * impact is negligible we set this flag for all USB disks
276 */
277 sdev->last_sector_bug = 1;
278
279 /*
280 * Enable last-sector hacks for single-target devices using
281 * the Bulk-only transport, unless we already know the
282 * capacity will be decremented or is correct.
283 */
284 if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
285 US_FL_SCM_MULT_TARG)) &&
286 us->protocol == USB_PR_BULK)
287 us->use_last_sector_hacks = 1;
288
289 /* Check if write cache default on flag is set or not */
290 if (us->fflags & US_FL_WRITE_CACHE)
291 sdev->wce_default_on = 1;
292
293 /* A few buggy USB-ATA bridges don't understand FUA */
294 if (us->fflags & US_FL_BROKEN_FUA)
295 sdev->broken_fua = 1;
296
297 /* Some even totally fail to indicate a cache */
298 if (us->fflags & US_FL_ALWAYS_SYNC) {
299 /* don't read caching information */
300 sdev->skip_ms_page_8 = 1;
301 sdev->skip_ms_page_3f = 1;
302 /* assume sync is needed */
303 sdev->wce_default_on = 1;
304 }
305 } else {
306
307 /*
308 * Non-disk-type devices don't need to ignore any pages
309 * or to force 192-byte transfer lengths for MODE SENSE.
310 * But they do need to use MODE SENSE(10).
311 */
312 sdev->use_10_for_ms = 1;
313
314 /* Some (fake) usb cdrom devices don't like READ_DISC_INFO */
315 if (us->fflags & US_FL_NO_READ_DISC_INFO)
316 sdev->no_read_disc_info = 1;
317 }
318
319 /*
320 * The CB and CBI transports have no way to pass LUN values
321 * other than the bits in the second byte of a CDB. But those
322 * bits don't get set to the LUN value if the device reports
323 * scsi_level == 0 (UNKNOWN). Hence such devices must necessarily
324 * be single-LUN.
325 */
326 if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
327 sdev->scsi_level == SCSI_UNKNOWN)
328 us->max_lun = 0;
329
330 /*
331 * Some devices choke when they receive a PREVENT-ALLOW MEDIUM
332 * REMOVAL command, so suppress those commands.
333 */
334 if (us->fflags & US_FL_NOT_LOCKABLE)
335 sdev->lockable = 0;
336
337 /*
338 * this is to satisfy the compiler, tho I don't think the
339 * return code is ever checked anywhere.
340 */
341 return 0;
342}
343
344static int target_alloc(struct scsi_target *starget)
345{
346 struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
347
348 /*
349 * Some USB drives don't support REPORT LUNS, even though they
350 * report a SCSI revision level above 2. Tell the SCSI layer
351 * not to issue that command; it will perform a normal sequential
352 * scan instead.
353 */
354 starget->no_report_luns = 1;
355
356 /*
357 * The UFI spec treats the Peripheral Qualifier bits in an
358 * INQUIRY result as reserved and requires devices to set them
359 * to 0. However the SCSI spec requires these bits to be set
360 * to 3 to indicate when a LUN is not present.
361 *
362 * Let the scanning code know if this target merely sets
363 * Peripheral Device Type to 0x1f to indicate no LUN.
364 */
365 if (us->subclass == USB_SC_UFI)
366 starget->pdt_1f_for_no_lun = 1;
367
368 return 0;
369}
370
371/* queue a command */
372/* This is always called with scsi_lock(host) held */
373static int queuecommand_lck(struct scsi_cmnd *srb)
374{
375 void (*done)(struct scsi_cmnd *) = scsi_done;
376 struct us_data *us = host_to_us(srb->device->host);
377
378 /* check for state-transition errors */
379 if (us->srb != NULL) {
380 dev_err(&us->pusb_intf->dev,
381 "Error in %s: us->srb = %p\n", __func__, us->srb);
382 return SCSI_MLQUEUE_HOST_BUSY;
383 }
384
385 /* fail the command if we are disconnecting */
386 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
387 usb_stor_dbg(us, "Fail command during disconnect\n");
388 srb->result = DID_NO_CONNECT << 16;
389 done(srb);
390 return 0;
391 }
392
393 if ((us->fflags & US_FL_NO_ATA_1X) &&
394 (srb->cmnd[0] == ATA_12 || srb->cmnd[0] == ATA_16)) {
395 memcpy(srb->sense_buffer, usb_stor_sense_invalidCDB,
396 sizeof(usb_stor_sense_invalidCDB));
397 srb->result = SAM_STAT_CHECK_CONDITION;
398 done(srb);
399 return 0;
400 }
401
402 /* enqueue the command and wake up the control thread */
403 us->srb = srb;
404 complete(&us->cmnd_ready);
405
406 return 0;
407}
408
409static DEF_SCSI_QCMD(queuecommand)
410
411/***********************************************************************
412 * Error handling functions
413 ***********************************************************************/
414
415/* Command timeout and abort */
416static int command_abort_matching(struct us_data *us, struct scsi_cmnd *srb_match)
417{
418 /*
419 * us->srb together with the TIMED_OUT, RESETTING, and ABORTING
420 * bits are protected by the host lock.
421 */
422 scsi_lock(us_to_host(us));
423
424 /* is there any active pending command to abort ? */
425 if (!us->srb) {
426 scsi_unlock(us_to_host(us));
427 usb_stor_dbg(us, "-- nothing to abort\n");
428 return SUCCESS;
429 }
430
431 /* Does the command match the passed srb if any ? */
432 if (srb_match && us->srb != srb_match) {
433 scsi_unlock(us_to_host(us));
434 usb_stor_dbg(us, "-- pending command mismatch\n");
435 return FAILED;
436 }
437
438 /*
439 * Set the TIMED_OUT bit. Also set the ABORTING bit, but only if
440 * a device reset isn't already in progress (to avoid interfering
441 * with the reset). Note that we must retain the host lock while
442 * calling usb_stor_stop_transport(); otherwise it might interfere
443 * with an auto-reset that begins as soon as we release the lock.
444 */
445 set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
446 if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
447 set_bit(US_FLIDX_ABORTING, &us->dflags);
448 usb_stor_stop_transport(us);
449 }
450 scsi_unlock(us_to_host(us));
451
452 /* Wait for the aborted command to finish */
453 wait_for_completion(&us->notify);
454 return SUCCESS;
455}
456
457static int command_abort(struct scsi_cmnd *srb)
458{
459 struct us_data *us = host_to_us(srb->device->host);
460
461 usb_stor_dbg(us, "%s called\n", __func__);
462 return command_abort_matching(us, srb);
463}
464
465/*
466 * This invokes the transport reset mechanism to reset the state of the
467 * device
468 */
469static int device_reset(struct scsi_cmnd *srb)
470{
471 struct us_data *us = host_to_us(srb->device->host);
472 int result;
473
474 usb_stor_dbg(us, "%s called\n", __func__);
475
476 /* abort any pending command before reset */
477 command_abort_matching(us, NULL);
478
479 /* lock the device pointers and do the reset */
480 mutex_lock(&(us->dev_mutex));
481 result = us->transport_reset(us);
482 mutex_unlock(&us->dev_mutex);
483
484 return result < 0 ? FAILED : SUCCESS;
485}
486
487/* Simulate a SCSI bus reset by resetting the device's USB port. */
488static int bus_reset(struct scsi_cmnd *srb)
489{
490 struct us_data *us = host_to_us(srb->device->host);
491 int result;
492
493 usb_stor_dbg(us, "%s called\n", __func__);
494
495 result = usb_stor_port_reset(us);
496 return result < 0 ? FAILED : SUCCESS;
497}
498
499/*
500 * Report a driver-initiated device reset to the SCSI layer.
501 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
502 * The caller must own the SCSI host lock.
503 */
504void usb_stor_report_device_reset(struct us_data *us)
505{
506 int i;
507 struct Scsi_Host *host = us_to_host(us);
508
509 scsi_report_device_reset(host, 0, 0);
510 if (us->fflags & US_FL_SCM_MULT_TARG) {
511 for (i = 1; i < host->max_id; ++i)
512 scsi_report_device_reset(host, 0, i);
513 }
514}
515
516/*
517 * Report a driver-initiated bus reset to the SCSI layer.
518 * Calling this for a SCSI-initiated reset is unnecessary but harmless.
519 * The caller must not own the SCSI host lock.
520 */
521void usb_stor_report_bus_reset(struct us_data *us)
522{
523 struct Scsi_Host *host = us_to_host(us);
524
525 scsi_lock(host);
526 scsi_report_bus_reset(host, 0);
527 scsi_unlock(host);
528}
529
530/***********************************************************************
531 * /proc/scsi/ functions
532 ***********************************************************************/
533
534static int write_info(struct Scsi_Host *host, char *buffer, int length)
535{
536 /* if someone is sending us data, just throw it away */
537 return length;
538}
539
540static int show_info (struct seq_file *m, struct Scsi_Host *host)
541{
542 struct us_data *us = host_to_us(host);
543 const char *string;
544
545 /* print the controller name */
546 seq_printf(m, " Host scsi%d: usb-storage\n", host->host_no);
547
548 /* print product, vendor, and serial number strings */
549 if (us->pusb_dev->manufacturer)
550 string = us->pusb_dev->manufacturer;
551 else if (us->unusual_dev->vendorName)
552 string = us->unusual_dev->vendorName;
553 else
554 string = "Unknown";
555 seq_printf(m, " Vendor: %s\n", string);
556 if (us->pusb_dev->product)
557 string = us->pusb_dev->product;
558 else if (us->unusual_dev->productName)
559 string = us->unusual_dev->productName;
560 else
561 string = "Unknown";
562 seq_printf(m, " Product: %s\n", string);
563 if (us->pusb_dev->serial)
564 string = us->pusb_dev->serial;
565 else
566 string = "None";
567 seq_printf(m, "Serial Number: %s\n", string);
568
569 /* show the protocol and transport */
570 seq_printf(m, " Protocol: %s\n", us->protocol_name);
571 seq_printf(m, " Transport: %s\n", us->transport_name);
572
573 /* show the device flags */
574 seq_printf(m, " Quirks:");
575
576#define US_FLAG(name, value) \
577 if (us->fflags & value) seq_printf(m, " " #name);
578US_DO_ALL_FLAGS
579#undef US_FLAG
580 seq_putc(m, '\n');
581 return 0;
582}
583
584/***********************************************************************
585 * Sysfs interface
586 ***********************************************************************/
587
588/* Output routine for the sysfs max_sectors file */
589static ssize_t max_sectors_show(struct device *dev, struct device_attribute *attr, char *buf)
590{
591 struct scsi_device *sdev = to_scsi_device(dev);
592
593 return sprintf(buf, "%u\n", queue_max_hw_sectors(sdev->request_queue));
594}
595
596/* Input routine for the sysfs max_sectors file */
597static ssize_t max_sectors_store(struct device *dev, struct device_attribute *attr, const char *buf,
598 size_t count)
599{
600 struct scsi_device *sdev = to_scsi_device(dev);
601 unsigned short ms;
602
603 if (sscanf(buf, "%hu", &ms) > 0) {
604 blk_queue_max_hw_sectors(sdev->request_queue, ms);
605 return count;
606 }
607 return -EINVAL;
608}
609static DEVICE_ATTR_RW(max_sectors);
610
611static struct attribute *usb_sdev_attrs[] = {
612 &dev_attr_max_sectors.attr,
613 NULL,
614};
615
616ATTRIBUTE_GROUPS(usb_sdev);
617
618/*
619 * this defines our host template, with which we'll allocate hosts
620 */
621
622static const struct scsi_host_template usb_stor_host_template = {
623 /* basic userland interface stuff */
624 .name = "usb-storage",
625 .proc_name = "usb-storage",
626 .show_info = show_info,
627 .write_info = write_info,
628 .info = host_info,
629
630 /* command interface -- queued only */
631 .queuecommand = queuecommand,
632
633 /* error and abort handlers */
634 .eh_abort_handler = command_abort,
635 .eh_device_reset_handler = device_reset,
636 .eh_bus_reset_handler = bus_reset,
637
638 /* queue commands only, only one command per LUN */
639 .can_queue = 1,
640
641 /* unknown initiator id */
642 .this_id = -1,
643
644 .slave_alloc = slave_alloc,
645 .slave_configure = slave_configure,
646 .target_alloc = target_alloc,
647
648 /* lots of sg segments can be handled */
649 .sg_tablesize = SG_MAX_SEGMENTS,
650
651
652 /*
653 * Limit the total size of a transfer to 120 KB.
654 *
655 * Some devices are known to choke with anything larger. It seems like
656 * the problem stems from the fact that original IDE controllers had
657 * only an 8-bit register to hold the number of sectors in one transfer
658 * and even those couldn't handle a full 256 sectors.
659 *
660 * Because we want to make sure we interoperate with as many devices as
661 * possible, we will maintain a 240 sector transfer size limit for USB
662 * Mass Storage devices.
663 *
664 * Tests show that other operating have similar limits with Microsoft
665 * Windows 7 limiting transfers to 128 sectors for both USB2 and USB3
666 * and Apple Mac OS X 10.11 limiting transfers to 256 sectors for USB2
667 * and 2048 for USB3 devices.
668 */
669 .max_sectors = 240,
670
671 /* emulated HBA */
672 .emulated = 1,
673
674 /* we do our own delay after a device or bus reset */
675 .skip_settle_delay = 1,
676
677 /* sysfs device attributes */
678 .sdev_groups = usb_sdev_groups,
679
680 /* module management */
681 .module = THIS_MODULE
682};
683
684void usb_stor_host_template_init(struct scsi_host_template *sht,
685 const char *name, struct module *owner)
686{
687 *sht = usb_stor_host_template;
688 sht->name = name;
689 sht->proc_name = name;
690 sht->module = owner;
691}
692EXPORT_SYMBOL_GPL(usb_stor_host_template_init);
693
694/* To Report "Illegal Request: Invalid Field in CDB */
695unsigned char usb_stor_sense_invalidCDB[18] = {
696 [0] = 0x70, /* current error */
697 [2] = ILLEGAL_REQUEST, /* Illegal Request = 0x05 */
698 [7] = 0x0a, /* additional length */
699 [12] = 0x24 /* Invalid Field in CDB */
700};
701EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);