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