1 // SPDX-License-Identifier: GPL-2.0+
3 * Driver for USB Mass Storage compliant devices
6 * Current development and maintenance by:
7 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
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)
14 * (c) 1999 Michael Gee (michael@linuxspecific.com)
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.
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.
27 * Also, for certain devices, the interrupt endpoint is used to convey
28 * status of a command.
31 #include <linux/blkdev.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/module.h>
34 #include <linux/mutex.h>
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>
43 #include <linux/usb/hcd.h>
46 #include "transport.h"
50 * Vendor IDs for companies that seem to include the READ CAPACITY bug
51 * in all their devices
53 #define VENDOR_ID_NOKIA 0x0421
54 #define VENDOR_ID_NIKON 0x04b0
55 #define VENDOR_ID_PENTAX 0x0a17
56 #define VENDOR_ID_MOTOROLA 0x22b8
58 /***********************************************************************
60 ***********************************************************************/
62 static const char* host_info(struct Scsi_Host *host)
64 struct us_data *us = host_to_us(host);
68 static int slave_alloc (struct scsi_device *sdev)
70 struct us_data *us = host_to_us(sdev->host);
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
77 sdev->inquiry_len = 36;
80 * Some host controllers may have alignment requirements.
81 * We'll play it safe by requiring 512-byte alignment always.
83 blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
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;
92 static int slave_configure(struct scsi_device *sdev)
94 struct us_data *us = host_to_us(sdev->host);
95 struct device *dev = us->pusb_dev->bus->sysdev;
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).
102 if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
103 unsigned int max_sectors = 64;
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,
110 } else if (sdev->type == TYPE_TAPE) {
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.
116 blk_queue_max_hw_sectors(sdev->request_queue, 0x7FFFFF);
117 } else if (us->pusb_dev->speed >= USB_SPEED_SUPER) {
119 * USB3 devices will be limited to 2048 sectors. This gives us
120 * better throughput on most devices.
122 blk_queue_max_hw_sectors(sdev->request_queue, 2048);
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.
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));
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.
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);
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.
147 if (sdev->type == TYPE_DISK) {
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.
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 |
164 us->fflags |= US_FL_CAPACITY_HEURISTICS;
169 * Disk-type devices use MODE SENSE(6) if the protocol
170 * (SubClass) is Transparent SCSI, otherwise they use
173 if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
174 sdev->use_10_for_ms = 1;
177 *Many disks only accept MODE SENSE transfer lengths of
178 * 192 bytes (that's what Windows uses).
180 sdev->use_192_bytes_for_3f = 1;
183 * Some devices report generic values until the media has been
184 * accessed. Force a READ(10) prior to querying device
187 sdev->read_before_ms = 1;
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.
198 if (us->fflags & US_FL_NO_WP_DETECT)
199 sdev->skip_ms_page_3f = 1;
202 * A number of devices have problems with MODE SENSE for
203 * page x08, so we will skip it.
205 sdev->skip_ms_page_8 = 1;
208 * Some devices don't handle VPD pages correctly, so skip vpd
209 * pages if not forced by SCSI layer.
211 sdev->skip_vpd_pages = !sdev->try_vpd_pages;
213 /* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
214 sdev->no_report_opcodes = 1;
216 /* Do not attempt to use WRITE SAME */
217 sdev->no_write_same = 1;
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.
224 if (us->fflags & US_FL_FIX_CAPACITY)
225 sdev->fix_capacity = 1;
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.
232 if (us->fflags & US_FL_CAPACITY_HEURISTICS)
233 sdev->guess_capacity = 1;
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;
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
245 if (!(us->fflags & US_FL_NEEDS_CAP16))
246 sdev->try_rc_10_first = 1;
249 * assume SPC3 or latter devices support sense size > 18
250 * unless US_FL_BAD_SENSE quirk is specified.
252 if (sdev->scsi_level > SCSI_SPC_2 &&
253 !(us->fflags & US_FL_BAD_SENSE))
254 us->fflags |= US_FL_SANE_SENSE;
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.
264 sdev->retry_hwerror = 1;
267 * USB disks should allow restart. Some drives spin down
268 * automatically, requiring a START-STOP UNIT command.
270 sdev->allow_restart = 1;
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
277 sdev->last_sector_bug = 1;
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.
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;
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;
293 /* A few buggy USB-ATA bridges don't understand FUA */
294 if (us->fflags & US_FL_BROKEN_FUA)
295 sdev->broken_fua = 1;
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;
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).
312 sdev->use_10_for_ms = 1;
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;
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
326 if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
327 sdev->scsi_level == SCSI_UNKNOWN)
331 * Some devices choke when they receive a PREVENT-ALLOW MEDIUM
332 * REMOVAL command, so suppress those commands.
334 if (us->fflags & US_FL_NOT_LOCKABLE)
338 * this is to satisfy the compiler, tho I don't think the
339 * return code is ever checked anywhere.
344 static int target_alloc(struct scsi_target *starget)
346 struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
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
354 starget->no_report_luns = 1;
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.
362 * Let the scanning code know if this target merely sets
363 * Peripheral Device Type to 0x1f to indicate no LUN.
365 if (us->subclass == USB_SC_UFI)
366 starget->pdt_1f_for_no_lun = 1;
371 /* queue a command */
372 /* This is always called with scsi_lock(host) held */
373 static int queuecommand_lck(struct scsi_cmnd *srb)
375 void (*done)(struct scsi_cmnd *) = scsi_done;
376 struct us_data *us = host_to_us(srb->device->host);
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;
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;
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;
402 /* enqueue the command and wake up the control thread */
404 complete(&us->cmnd_ready);
409 static DEF_SCSI_QCMD(queuecommand)
411 /***********************************************************************
412 * Error handling functions
413 ***********************************************************************/
415 /* Command timeout and abort */
416 static int command_abort_matching(struct us_data *us, struct scsi_cmnd *srb_match)
419 * us->srb together with the TIMED_OUT, RESETTING, and ABORTING
420 * bits are protected by the host lock.
422 scsi_lock(us_to_host(us));
424 /* is there any active pending command to abort ? */
426 scsi_unlock(us_to_host(us));
427 usb_stor_dbg(us, "-- nothing to abort\n");
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");
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.
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);
450 scsi_unlock(us_to_host(us));
452 /* Wait for the aborted command to finish */
453 wait_for_completion(&us->notify);
457 static int command_abort(struct scsi_cmnd *srb)
459 struct us_data *us = host_to_us(srb->device->host);
461 usb_stor_dbg(us, "%s called\n", __func__);
462 return command_abort_matching(us, srb);
466 * This invokes the transport reset mechanism to reset the state of the
469 static int device_reset(struct scsi_cmnd *srb)
471 struct us_data *us = host_to_us(srb->device->host);
474 usb_stor_dbg(us, "%s called\n", __func__);
476 /* abort any pending command before reset */
477 command_abort_matching(us, NULL);
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);
484 return result < 0 ? FAILED : SUCCESS;
487 /* Simulate a SCSI bus reset by resetting the device's USB port. */
488 static int bus_reset(struct scsi_cmnd *srb)
490 struct us_data *us = host_to_us(srb->device->host);
493 usb_stor_dbg(us, "%s called\n", __func__);
495 result = usb_stor_port_reset(us);
496 return result < 0 ? FAILED : SUCCESS;
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.
504 void usb_stor_report_device_reset(struct us_data *us)
507 struct Scsi_Host *host = us_to_host(us);
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);
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.
521 void usb_stor_report_bus_reset(struct us_data *us)
523 struct Scsi_Host *host = us_to_host(us);
526 scsi_report_bus_reset(host, 0);
530 /***********************************************************************
531 * /proc/scsi/ functions
532 ***********************************************************************/
534 static int write_info(struct Scsi_Host *host, char *buffer, int length)
536 /* if someone is sending us data, just throw it away */
540 static int show_info (struct seq_file *m, struct Scsi_Host *host)
542 struct us_data *us = host_to_us(host);
545 /* print the controller name */
546 seq_printf(m, " Host scsi%d: usb-storage\n", host->host_no);
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;
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;
562 seq_printf(m, " Product: %s\n", string);
563 if (us->pusb_dev->serial)
564 string = us->pusb_dev->serial;
567 seq_printf(m, "Serial Number: %s\n", string);
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);
573 /* show the device flags */
574 seq_printf(m, " Quirks:");
576 #define US_FLAG(name, value) \
577 if (us->fflags & value) seq_printf(m, " " #name);
584 /***********************************************************************
586 ***********************************************************************/
588 /* Output routine for the sysfs max_sectors file */
589 static ssize_t max_sectors_show(struct device *dev, struct device_attribute *attr, char *buf)
591 struct scsi_device *sdev = to_scsi_device(dev);
593 return sprintf(buf, "%u\n", queue_max_hw_sectors(sdev->request_queue));
596 /* Input routine for the sysfs max_sectors file */
597 static ssize_t max_sectors_store(struct device *dev, struct device_attribute *attr, const char *buf,
600 struct scsi_device *sdev = to_scsi_device(dev);
603 if (sscanf(buf, "%hu", &ms) > 0) {
604 blk_queue_max_hw_sectors(sdev->request_queue, ms);
609 static DEVICE_ATTR_RW(max_sectors);
611 static struct attribute *usb_sdev_attrs[] = {
612 &dev_attr_max_sectors.attr,
616 ATTRIBUTE_GROUPS(usb_sdev);
619 * this defines our host template, with which we'll allocate hosts
622 static 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,
630 /* command interface -- queued only */
631 .queuecommand = queuecommand,
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,
638 /* queue commands only, only one command per LUN */
641 /* unknown initiator id */
644 .slave_alloc = slave_alloc,
645 .slave_configure = slave_configure,
646 .target_alloc = target_alloc,
648 /* lots of sg segments can be handled */
649 .sg_tablesize = SG_MAX_SEGMENTS,
653 * Limit the total size of a transfer to 120 KB.
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.
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.
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.
674 /* we do our own delay after a device or bus reset */
675 .skip_settle_delay = 1,
677 /* sysfs device attributes */
678 .sdev_groups = usb_sdev_groups,
680 /* module management */
681 .module = THIS_MODULE
684 void usb_stor_host_template_init(struct scsi_host_template *sht,
685 const char *name, struct module *owner)
687 *sht = usb_stor_host_template;
689 sht->proc_name = name;
692 EXPORT_SYMBOL_GPL(usb_stor_host_template_init);
694 /* To Report "Illegal Request: Invalid Field in CDB */
695 unsigned 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 */
701 EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);