Line data Source code
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/slab.h>
47 : #include <linux/module.h>
48 : #include <linux/mutex.h>
49 :
50 : #include <scsi/scsi.h>
51 : #include <scsi/scsi_cmnd.h>
52 : #include <scsi/scsi_devinfo.h>
53 : #include <scsi/scsi_device.h>
54 : #include <scsi/scsi_eh.h>
55 :
56 : #include "usb.h"
57 : #include "scsiglue.h"
58 : #include "debug.h"
59 : #include "transport.h"
60 : #include "protocol.h"
61 :
62 : /* Vendor IDs for companies that seem to include the READ CAPACITY bug
63 : * in all their devices
64 : */
65 : #define VENDOR_ID_NOKIA 0x0421
66 : #define VENDOR_ID_NIKON 0x04b0
67 : #define VENDOR_ID_PENTAX 0x0a17
68 : #define VENDOR_ID_MOTOROLA 0x22b8
69 :
70 : /***********************************************************************
71 : * Host functions
72 : ***********************************************************************/
73 :
74 : static const char* host_info(struct Scsi_Host *host)
75 : {
76 4 : struct us_data *us = host_to_us(host);
77 2 : return us->scsi_name;
78 : }
79 :
80 : static int slave_alloc (struct scsi_device *sdev)
81 : {
82 4 : struct us_data *us = host_to_us(sdev->host);
83 1 :
84 : /*
85 : * Set the INQUIRY transfer length to 36. We don't use any of
86 : * the extra data and many devices choke if asked for more or
87 : * less than 36 bytes.
88 : */
89 1 : sdev->inquiry_len = 36;
90 :
91 : /* USB has unusual DMA-alignment requirements: Although the
92 : * starting address of each scatter-gather element doesn't matter,
93 : * the length of each element except the last must be divisible
94 : * by the Bulk maxpacket value. There's currently no way to
95 : * express this by block-layer constraints, so we'll cop out
96 : * and simply require addresses to be aligned at 512-byte
97 : * boundaries. This is okay since most block I/O involves
98 : * hardware sectors that are multiples of 512 bytes in length,
99 : * and since host controllers up through USB 2.0 have maxpacket
100 : * values no larger than 512.
101 : *
102 : * But it doesn't suffice for Wireless USB, where Bulk maxpacket
103 : * values can be as large as 2048. To make that work properly
104 : * will require changes to the block layer.
105 : */
106 1 : blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
107 :
108 : /*
109 : * The UFI spec treates the Peripheral Qualifier bits in an
110 : * INQUIRY result as reserved and requires devices to set them
111 : * to 0. However the SCSI spec requires these bits to be set
112 : * to 3 to indicate when a LUN is not present.
113 : *
114 : * Let the scanning code know if this target merely sets
115 : * Peripheral Device Type to 0x1f to indicate no LUN.
116 : */
117 3 : if (us->subclass == US_SC_UFI)
118 1 : sdev->sdev_target->pdt_1f_for_no_lun = 1;
119 :
120 1 : return 0;
121 : }
122 :
123 : static int slave_configure(struct scsi_device *sdev)
124 : {
125 4 : struct us_data *us = host_to_us(sdev->host);
126 1 :
127 1 : /* Many devices have trouble transfering more than 32KB at a time,
128 1 : * while others have trouble with more than 64K. At this time we
129 1 : * are limiting both to 32K (64 sectores).
130 : */
131 2 : if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
132 1 : unsigned int max_sectors = 64;
133 :
134 2 : if (us->fflags & US_FL_MAX_SECTORS_MIN)
135 1 : max_sectors = PAGE_CACHE_SIZE >> 9;
136 4 : if (queue_max_sectors(sdev->request_queue) > max_sectors)
137 1 : blk_queue_max_sectors(sdev->request_queue,
138 : max_sectors);
139 3 : } else if (sdev->type == TYPE_TAPE) {
140 : /* Tapes need much higher max_sector limits, so just
141 : * raise it to the maximum possible (4 GB / 512) and
142 : * let the queue segment size sort out the real limit.
143 : */
144 1 : blk_queue_max_sectors(sdev->request_queue, 0x7FFFFF);
145 : }
146 :
147 : /* Some USB host controllers can't do DMA; they have to use PIO.
148 : * They indicate this by setting their dma_mask to NULL. For
149 : * such controllers we need to make sure the block layer sets
150 : * up bounce buffers in addressable memory.
151 : */
152 6 : if (!us->pusb_dev->bus->controller->dma_mask)
153 2 : blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
154 :
155 : /* We can't put these settings in slave_alloc() because that gets
156 : * called before the device type is known. Consequently these
157 : * settings can't be overridden via the scsi devinfo mechanism. */
158 6 : if (sdev->type == TYPE_DISK) {
159 :
160 : /* Some vendors seem to put the READ CAPACITY bug into
161 : * all their devices -- primarily makers of cell phones
162 : * and digital cameras. Since these devices always use
163 : * flash media and can be expected to have an even number
164 : * of sectors, we will always enable the CAPACITY_HEURISTICS
165 : * flag unless told otherwise. */
166 2 : switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
167 8 : case VENDOR_ID_NOKIA:
168 8 : case VENDOR_ID_NIKON:
169 8 : case VENDOR_ID_PENTAX:
170 8 : case VENDOR_ID_MOTOROLA:
171 4 : if (!(us->fflags & (US_FL_FIX_CAPACITY |
172 : US_FL_CAPACITY_OK)))
173 2 : us->fflags |= US_FL_CAPACITY_HEURISTICS;
174 2 : break;
175 2 : }
176 :
177 2 : /* Disk-type devices use MODE SENSE(6) if the protocol
178 : * (SubClass) is Transparent SCSI, otherwise they use
179 : * MODE SENSE(10). */
180 12 : if (us->subclass != US_SC_SCSI && us->subclass != US_SC_CYP_ATACB)
181 2 : sdev->use_10_for_ms = 1;
182 :
183 : /* Many disks only accept MODE SENSE transfer lengths of
184 : * 192 bytes (that's what Windows uses). */
185 2 : sdev->use_192_bytes_for_3f = 1;
186 :
187 : /* Some devices don't like MODE SENSE with page=0x3f,
188 : * which is the command used for checking if a device
189 : * is write-protected. Now that we tell the sd driver
190 : * to do a 192-byte transfer with this command the
191 : * majority of devices work fine, but a few still can't
192 : * handle it. The sd driver will simply assume those
193 : * devices are write-enabled. */
194 4 : if (us->fflags & US_FL_NO_WP_DETECT)
195 2 : sdev->skip_ms_page_3f = 1;
196 :
197 : /* A number of devices have problems with MODE SENSE for
198 : * page x08, so we will skip it. */
199 2 : sdev->skip_ms_page_8 = 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 4 : if (us->fflags & US_FL_FIX_CAPACITY)
205 2 : 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 4 : if (us->fflags & US_FL_CAPACITY_HEURISTICS)
211 2 : sdev->guess_capacity = 1;
212 :
213 : /* assume SPC3 or latter devices support sense size > 18 */
214 6 : if (sdev->scsi_level > SCSI_SPC_2)
215 2 : us->fflags |= US_FL_SANE_SENSE;
216 :
217 : /* Some devices report a SCSI revision level above 2 but are
218 : * unable to handle the REPORT LUNS command (for which
219 : * support is mandatory at level 3). Since we already have
220 : * a Get-Max-LUN request, we won't lose much by setting the
221 : * revision level down to 2. The only devices that would be
222 : * affected are those with sparse LUNs. */
223 6 : if (sdev->scsi_level > SCSI_2)
224 6 : sdev->sdev_target->scsi_level =
225 : sdev->scsi_level = SCSI_2;
226 :
227 : /* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
228 : * Hardware Error) when any low-level error occurs,
229 : * recoverable or not. Setting this flag tells the SCSI
230 : * midlayer to retry such commands, which frequently will
231 : * succeed and fix the error. The worst this can lead to
232 : * is an occasional series of retries that will all fail. */
233 2 : sdev->retry_hwerror = 1;
234 :
235 : /* USB disks should allow restart. Some drives spin down
236 : * automatically, requiring a START-STOP UNIT command. */
237 2 : sdev->allow_restart = 1;
238 :
239 : /* Some USB cardreaders have trouble reading an sdcard's last
240 : * sector in a larger then 1 sector read, since the performance
241 : * impact is negible we set this flag for all USB disks */
242 2 : sdev->last_sector_bug = 1;
243 :
244 : /* Enable last-sector hacks for single-target devices using
245 : * the Bulk-only transport, unless we already know the
246 : * capacity will be decremented or is correct. */
247 10 : if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
248 : US_FL_SCM_MULT_TARG)) &&
249 : us->protocol == US_PR_BULK)
250 2 : us->use_last_sector_hacks = 1;
251 : } else {
252 :
253 : /* Non-disk-type devices don't need to blacklist any pages
254 : * or to force 192-byte transfer lengths for MODE SENSE.
255 : * But they do need to use MODE SENSE(10). */
256 2 : sdev->use_10_for_ms = 1;
257 : }
258 :
259 : /* The CB and CBI transports have no way to pass LUN values
260 : * other than the bits in the second byte of a CDB. But those
261 : * bits don't get set to the LUN value if the device reports
262 : * scsi_level == 0 (UNKNOWN). Hence such devices must necessarily
263 : * be single-LUN.
264 : */
265 12 : if ((us->protocol == US_PR_CB || us->protocol == US_PR_CBI) &&
266 : sdev->scsi_level == SCSI_UNKNOWN)
267 2 : us->max_lun = 0;
268 :
269 : /* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
270 : * REMOVAL command, so suppress those commands. */
271 4 : if (us->fflags & US_FL_NOT_LOCKABLE)
272 2 : sdev->lockable = 0;
273 :
274 : /* this is to satisfy the compiler, tho I don't think the
275 : * return code is ever checked anywhere. */
276 2 : return 0;
277 : }
278 :
279 : /* queue a command */
280 : /* This is always called with scsi_lock(host) held */
281 : static int queuecommand(struct scsi_cmnd *srb,
282 : void (*done)(struct scsi_cmnd *))
283 1 : {
284 4 : struct us_data *us = host_to_us(srb->device->host);
285 1 :
286 : US_DEBUGP("%s called\n", __func__);
287 :
288 : /* check for state-transition errors */
289 3 : if (us->srb != NULL) {
290 1 : printk(KERN_ERR USB_STORAGE "Error in %s: us->srb = %p\n",
291 : __func__, us->srb);
292 1 : return SCSI_MLQUEUE_HOST_BUSY;
293 : }
294 :
295 : /* fail the command if we are disconnecting */
296 4 : if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
297 : US_DEBUGP("Fail command during disconnect\n");
298 1 : srb->result = DID_NO_CONNECT << 16;
299 1 : done(srb);
300 1 : return 0;
301 : }
302 :
303 : /* enqueue the command and wake up the control thread */
304 1 : srb->scsi_done = done;
305 1 : us->srb = srb;
306 1 : complete(&us->cmnd_ready);
307 :
308 1 : return 0;
309 : }
310 :
311 : /***********************************************************************
312 : * Error handling functions
313 : ***********************************************************************/
314 :
315 : /* Command timeout and abort */
316 : static int command_abort(struct scsi_cmnd *srb)
317 : {
318 4 : struct us_data *us = host_to_us(srb->device->host);
319 1 :
320 1 : US_DEBUGP("%s called\n", __func__);
321 1 :
322 1 : /* us->srb together with the TIMED_OUT, RESETTING, and ABORTING
323 1 : * bits are protected by the host lock. */
324 4 : scsi_lock(us_to_host(us));
325 :
326 : /* Is this command still active? */
327 3 : if (us->srb != srb) {
328 4 : scsi_unlock(us_to_host(us));
329 : US_DEBUGP ("-- nothing to abort\n");
330 1 : return FAILED;
331 : }
332 :
333 : /* Set the TIMED_OUT bit. Also set the ABORTING bit, but only if
334 : * a device reset isn't already in progress (to avoid interfering
335 : * with the reset). Note that we must retain the host lock while
336 : * calling usb_stor_stop_transport(); otherwise it might interfere
337 : * with an auto-reset that begins as soon as we release the lock. */
338 2 : set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
339 4 : if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
340 2 : set_bit(US_FLIDX_ABORTING, &us->dflags);
341 2 : usb_stor_stop_transport(us);
342 : }
343 6 : scsi_unlock(us_to_host(us));
344 :
345 : /* Wait for the aborted command to finish */
346 1 : wait_for_completion(&us->notify);
347 1 : return SUCCESS;
348 : }
349 :
350 : /* This invokes the transport reset mechanism to reset the state of the
351 : * device */
352 : static int device_reset(struct scsi_cmnd *srb)
353 : {
354 4 : struct us_data *us = host_to_us(srb->device->host);
355 1 : int result;
356 1 :
357 : US_DEBUGP("%s called\n", __func__);
358 :
359 : /* lock the device pointers and do the reset */
360 1 : mutex_lock(&(us->dev_mutex));
361 10 : result = us->transport_reset(us);
362 1 : mutex_unlock(&us->dev_mutex);
363 :
364 6 : return result < 0 ? FAILED : SUCCESS;
365 : }
366 :
367 : /* Simulate a SCSI bus reset by resetting the device's USB port. */
368 : static int bus_reset(struct scsi_cmnd *srb)
369 : {
370 4 : struct us_data *us = host_to_us(srb->device->host);
371 1 : int result;
372 1 :
373 : US_DEBUGP("%s called\n", __func__);
374 4 : result = usb_stor_port_reset(us);
375 6 : return result < 0 ? FAILED : SUCCESS;
376 : }
377 :
378 : /* Report a driver-initiated device reset to the SCSI layer.
379 : * Calling this for a SCSI-initiated reset is unnecessary but harmless.
380 : * The caller must own the SCSI host lock. */
381 : void usb_stor_report_device_reset(struct us_data *us)
382 : {
383 0 : int i;
384 0 : struct Scsi_Host *host = us_to_host(us);
385 0 :
386 0 : scsi_report_device_reset(host, 0, 0);
387 0 : if (us->fflags & US_FL_SCM_MULT_TARG) {
388 0 : for (i = 1; i < host->max_id; ++i)
389 0 : scsi_report_device_reset(host, 0, i);
390 0 : }
391 : }
392 :
393 : /* Report a driver-initiated bus reset to the SCSI layer.
394 : * Calling this for a SCSI-initiated reset is unnecessary but harmless.
395 : * The caller must not own the SCSI host lock. */
396 0 : void usb_stor_report_bus_reset(struct us_data *us)
397 : {
398 4 : struct Scsi_Host *host = us_to_host(us);
399 1 :
400 2 : scsi_lock(host);
401 1 : scsi_report_bus_reset(host, 0);
402 2 : scsi_unlock(host);
403 1 : }
404 :
405 : /***********************************************************************
406 : * /proc/scsi/ functions
407 : ***********************************************************************/
408 :
409 : /* we use this macro to help us write into the buffer */
410 : #undef SPRINTF
411 : #define SPRINTF(args...) \
412 : do { if (pos < buffer+length) pos += sprintf(pos, ## args); } while (0)
413 :
414 : static int proc_info (struct Scsi_Host *host, char *buffer,
415 : char **start, off_t offset, int length, int inout)
416 : {
417 4 : struct us_data *us = host_to_us(host);
418 2 : char *pos = buffer;
419 1 : const char *string;
420 1 :
421 1 : /* if someone is sending us data, just throw it away */
422 3 : if (inout)
423 2 : return length;
424 1 :
425 1 : /* print the controller name */
426 5 : SPRINTF(" Host scsi%d: usb-storage\n", host->host_no);
427 1 :
428 1 : /* print product, vendor, and serial number strings */
429 4 : if (us->pusb_dev->manufacturer)
430 3 : string = us->pusb_dev->manufacturer;
431 4 : else if (us->unusual_dev->vendorName)
432 2 : string = us->unusual_dev->vendorName;
433 1 : else
434 2 : string = "Unknown";
435 5 : SPRINTF(" Vendor: %s\n", string);
436 4 : if (us->pusb_dev->product)
437 3 : string = us->pusb_dev->product;
438 4 : else if (us->unusual_dev->productName)
439 2 : string = us->unusual_dev->productName;
440 1 : else
441 2 : string = "Unknown";
442 5 : SPRINTF(" Product: %s\n", string);
443 4 : if (us->pusb_dev->serial)
444 3 : string = us->pusb_dev->serial;
445 1 : else
446 2 : string = "None";
447 4 : SPRINTF("Serial Number: %s\n", string);
448 :
449 : /* show the protocol and transport */
450 4 : SPRINTF(" Protocol: %s\n", us->protocol_name);
451 4 : SPRINTF(" Transport: %s\n", us->transport_name);
452 :
453 : /* show the device flags */
454 2 : if (pos < buffer + length) {
455 2 : pos += sprintf(pos, " Quirks:");
456 :
457 : #define US_FLAG(name, value) \
458 : if (us->fflags & value) pos += sprintf(pos, " " #name);
459 73 : US_DO_ALL_FLAGS
460 : #undef US_FLAG
461 :
462 3 : *(pos++) = '\n';
463 : }
464 :
465 : /*
466 : * Calculate start of next buffer, and return value.
467 : */
468 1 : *start = buffer + offset;
469 :
470 2 : if ((pos - buffer) < offset)
471 1 : return (0);
472 2 : else if ((pos - buffer - offset) < length)
473 1 : return (pos - buffer - offset);
474 : else
475 1 : return (length);
476 : }
477 :
478 : /***********************************************************************
479 : * Sysfs interface
480 : ***********************************************************************/
481 :
482 : /* Output routine for the sysfs max_sectors file */
483 : static ssize_t show_max_sectors(struct device *dev, struct device_attribute *attr, char *buf)
484 : {
485 2 : struct scsi_device *sdev = to_scsi_device(dev);
486 1 :
487 5 : return sprintf(buf, "%u\n", queue_max_sectors(sdev->request_queue));
488 1 : }
489 1 :
490 : /* Input routine for the sysfs max_sectors file */
491 : static ssize_t store_max_sectors(struct device *dev, struct device_attribute *attr, const char *buf,
492 : size_t count)
493 : {
494 3 : struct scsi_device *sdev = to_scsi_device(dev);
495 1 : unsigned short ms;
496 1 :
497 6 : if (sscanf(buf, "%hu", &ms) > 0 && ms <= SCSI_DEFAULT_MAX_SECTORS) {
498 2 : blk_queue_max_sectors(sdev->request_queue, ms);
499 2 : return strlen(buf);
500 : }
501 1 : return -EINVAL;
502 : }
503 :
504 : static DEVICE_ATTR(max_sectors, S_IRUGO | S_IWUSR, show_max_sectors,
505 1 : store_max_sectors);
506 :
507 1 : static struct device_attribute *sysfs_device_attr_list[] = {
508 : &dev_attr_max_sectors,
509 : NULL,
510 : };
511 :
512 : /*
513 : * this defines our host template, with which we'll allocate hosts
514 : */
515 :
516 1 : struct scsi_host_template usb_stor_host_template = {
517 : /* basic userland interface stuff */
518 : .name = "usb-storage",
519 : .proc_name = "usb-storage",
520 : .proc_info = proc_info,
521 : .info = host_info,
522 :
523 : /* command interface -- queued only */
524 : .queuecommand = queuecommand,
525 :
526 : /* error and abort handlers */
527 : .eh_abort_handler = command_abort,
528 : .eh_device_reset_handler = device_reset,
529 : .eh_bus_reset_handler = bus_reset,
530 :
531 : /* queue commands only, only one command per LUN */
532 : .can_queue = 1,
533 : .cmd_per_lun = 1,
534 :
535 : /* unknown initiator id */
536 : .this_id = -1,
537 :
538 : .slave_alloc = slave_alloc,
539 : .slave_configure = slave_configure,
540 :
541 : /* lots of sg segments can be handled */
542 : .sg_tablesize = SG_ALL,
543 :
544 : /* limit the total size of a transfer to 120 KB */
545 : .max_sectors = 240,
546 :
547 : /* merge commands... this seems to help performance, but
548 : * periodically someone should test to see which setting is more
549 : * optimal.
550 : */
551 : .use_clustering = 1,
552 :
553 : /* emulated HBA */
554 : .emulated = 1,
555 :
556 : /* we do our own delay after a device or bus reset */
557 : .skip_settle_delay = 1,
558 :
559 : /* sysfs device attributes */
560 : .sdev_attrs = sysfs_device_attr_list,
561 :
562 : /* module management */
563 : .module = THIS_MODULE
564 : };
565 :
566 : /* To Report "Illegal Request: Invalid Field in CDB */
567 1 : unsigned char usb_stor_sense_invalidCDB[18] = {
568 : [0] = 0x70, /* current error */
569 : [2] = ILLEGAL_REQUEST, /* Illegal Request = 0x05 */
570 : [7] = 0x0a, /* additional length */
571 : [12] = 0x24 /* Invalid Field in CDB */
572 : };
573 : EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);
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