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1/* Driver for USB Mass Storage compliant devices
2 *
3 * Current development and maintenance by:
4 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
5 *
6 * Developed with the assistance of:
7 * (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
8 * (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
9 * (c) 2002 Alan Stern <stern@rowland.org>
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/sched.h>
47#include <linux/gfp.h>
48#include <linux/errno.h>
49
50#include <linux/usb/quirks.h>
51
52#include <scsi/scsi.h>
53#include <scsi/scsi_eh.h>
54#include <scsi/scsi_device.h>
55
56#include "usb.h"
57#include "transport.h"
58#include "protocol.h"
59#include "scsiglue.h"
60#include "debug.h"
61
62#include <linux/blkdev.h>
63#include "../../scsi/sd.h"
64
65
66/***********************************************************************
67 * Data transfer routines
68 ***********************************************************************/
69
70/*
71 * This is subtle, so pay attention:
72 * ---------------------------------
73 * We're very concerned about races with a command abort. Hanging this code
74 * is a sure fire way to hang the kernel. (Note that this discussion applies
75 * only to transactions resulting from a scsi queued-command, since only
76 * these transactions are subject to a scsi abort. Other transactions, such
77 * as those occurring during device-specific initialization, must be handled
78 * by a separate code path.)
79 *
80 * The abort function (usb_storage_command_abort() in scsiglue.c) first
81 * sets the machine state and the ABORTING bit in us->dflags to prevent
82 * new URBs from being submitted. It then calls usb_stor_stop_transport()
83 * below, which atomically tests-and-clears the URB_ACTIVE bit in us->dflags
84 * to see if the current_urb needs to be stopped. Likewise, the SG_ACTIVE
85 * bit is tested to see if the current_sg scatter-gather request needs to be
86 * stopped. The timeout callback routine does much the same thing.
87 *
88 * When a disconnect occurs, the DISCONNECTING bit in us->dflags is set to
89 * prevent new URBs from being submitted, and usb_stor_stop_transport() is
90 * called to stop any ongoing requests.
91 *
92 * The submit function first verifies that the submitting is allowed
93 * (neither ABORTING nor DISCONNECTING bits are set) and that the submit
94 * completes without errors, and only then sets the URB_ACTIVE bit. This
95 * prevents the stop_transport() function from trying to cancel the URB
96 * while the submit call is underway. Next, the submit function must test
97 * the flags to see if an abort or disconnect occurred during the submission
98 * or before the URB_ACTIVE bit was set. If so, it's essential to cancel
99 * the URB if it hasn't been cancelled already (i.e., if the URB_ACTIVE bit
100 * is still set). Either way, the function must then wait for the URB to
101 * finish. Note that the URB can still be in progress even after a call to
102 * usb_unlink_urb() returns.
103 *
104 * The idea is that (1) once the ABORTING or DISCONNECTING bit is set,
105 * either the stop_transport() function or the submitting function
106 * is guaranteed to call usb_unlink_urb() for an active URB,
107 * and (2) test_and_clear_bit() prevents usb_unlink_urb() from being
108 * called more than once or from being called during usb_submit_urb().
109 */
110
111/* This is the completion handler which will wake us up when an URB
112 * completes.
113 */
114static void usb_stor_blocking_completion(struct urb *urb)
115{
116 struct completion *urb_done_ptr = urb->context;
117
118 complete(urb_done_ptr);
119}
120
121/* This is the common part of the URB message submission code
122 *
123 * All URBs from the usb-storage driver involved in handling a queued scsi
124 * command _must_ pass through this function (or something like it) for the
125 * abort mechanisms to work properly.
126 */
127static int usb_stor_msg_common(struct us_data *us, int timeout)
128{
129 struct completion urb_done;
130 long timeleft;
131 int status;
132
133 /* don't submit URBs during abort processing */
134 if (test_bit(US_FLIDX_ABORTING, &us->dflags))
135 return -EIO;
136
137 /* set up data structures for the wakeup system */
138 init_completion(&urb_done);
139
140 /* fill the common fields in the URB */
141 us->current_urb->context = &urb_done;
142 us->current_urb->transfer_flags = 0;
143
144 /* we assume that if transfer_buffer isn't us->iobuf then it
145 * hasn't been mapped for DMA. Yes, this is clunky, but it's
146 * easier than always having the caller tell us whether the
147 * transfer buffer has already been mapped. */
148 if (us->current_urb->transfer_buffer == us->iobuf)
149 us->current_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
150 us->current_urb->transfer_dma = us->iobuf_dma;
151
152 /* submit the URB */
153 status = usb_submit_urb(us->current_urb, GFP_NOIO);
154 if (status) {
155 /* something went wrong */
156 return status;
157 }
158
159 /* since the URB has been submitted successfully, it's now okay
160 * to cancel it */
161 set_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
162
163 /* did an abort occur during the submission? */
164 if (test_bit(US_FLIDX_ABORTING, &us->dflags)) {
165
166 /* cancel the URB, if it hasn't been cancelled already */
167 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
168 US_DEBUGP("-- cancelling URB\n");
169 usb_unlink_urb(us->current_urb);
170 }
171 }
172
173 /* wait for the completion of the URB */
174 timeleft = wait_for_completion_interruptible_timeout(
175 &urb_done, timeout ? : MAX_SCHEDULE_TIMEOUT);
176
177 clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
178
179 if (timeleft <= 0) {
180 US_DEBUGP("%s -- cancelling URB\n",
181 timeleft == 0 ? "Timeout" : "Signal");
182 usb_kill_urb(us->current_urb);
183 }
184
185 /* return the URB status */
186 return us->current_urb->status;
187}
188
189/*
190 * Transfer one control message, with timeouts, and allowing early
191 * termination. Return codes are usual -Exxx, *not* USB_STOR_XFER_xxx.
192 */
193int usb_stor_control_msg(struct us_data *us, unsigned int pipe,
194 u8 request, u8 requesttype, u16 value, u16 index,
195 void *data, u16 size, int timeout)
196{
197 int status;
198
199 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
200 __func__, request, requesttype,
201 value, index, size);
202
203 /* fill in the devrequest structure */
204 us->cr->bRequestType = requesttype;
205 us->cr->bRequest = request;
206 us->cr->wValue = cpu_to_le16(value);
207 us->cr->wIndex = cpu_to_le16(index);
208 us->cr->wLength = cpu_to_le16(size);
209
210 /* fill and submit the URB */
211 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe,
212 (unsigned char*) us->cr, data, size,
213 usb_stor_blocking_completion, NULL);
214 status = usb_stor_msg_common(us, timeout);
215
216 /* return the actual length of the data transferred if no error */
217 if (status == 0)
218 status = us->current_urb->actual_length;
219 return status;
220}
221EXPORT_SYMBOL_GPL(usb_stor_control_msg);
222
223/* This is a version of usb_clear_halt() that allows early termination and
224 * doesn't read the status from the device -- this is because some devices
225 * crash their internal firmware when the status is requested after a halt.
226 *
227 * A definitive list of these 'bad' devices is too difficult to maintain or
228 * make complete enough to be useful. This problem was first observed on the
229 * Hagiwara FlashGate DUAL unit. However, bus traces reveal that neither
230 * MacOS nor Windows checks the status after clearing a halt.
231 *
232 * Since many vendors in this space limit their testing to interoperability
233 * with these two OSes, specification violations like this one are common.
234 */
235int usb_stor_clear_halt(struct us_data *us, unsigned int pipe)
236{
237 int result;
238 int endp = usb_pipeendpoint(pipe);
239
240 if (usb_pipein (pipe))
241 endp |= USB_DIR_IN;
242
243 result = usb_stor_control_msg(us, us->send_ctrl_pipe,
244 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
245 USB_ENDPOINT_HALT, endp,
246 NULL, 0, 3*HZ);
247
248 if (result >= 0)
249 usb_reset_endpoint(us->pusb_dev, endp);
250
251 US_DEBUGP("%s: result = %d\n", __func__, result);
252 return result;
253}
254EXPORT_SYMBOL_GPL(usb_stor_clear_halt);
255
256
257/*
258 * Interpret the results of a URB transfer
259 *
260 * This function prints appropriate debugging messages, clears halts on
261 * non-control endpoints, and translates the status to the corresponding
262 * USB_STOR_XFER_xxx return code.
263 */
264static int interpret_urb_result(struct us_data *us, unsigned int pipe,
265 unsigned int length, int result, unsigned int partial)
266{
267 US_DEBUGP("Status code %d; transferred %u/%u\n",
268 result, partial, length);
269 switch (result) {
270
271 /* no error code; did we send all the data? */
272 case 0:
273 if (partial != length) {
274 US_DEBUGP("-- short transfer\n");
275 return USB_STOR_XFER_SHORT;
276 }
277
278 US_DEBUGP("-- transfer complete\n");
279 return USB_STOR_XFER_GOOD;
280
281 /* stalled */
282 case -EPIPE:
283 /* for control endpoints, (used by CB[I]) a stall indicates
284 * a failed command */
285 if (usb_pipecontrol(pipe)) {
286 US_DEBUGP("-- stall on control pipe\n");
287 return USB_STOR_XFER_STALLED;
288 }
289
290 /* for other sorts of endpoint, clear the stall */
291 US_DEBUGP("clearing endpoint halt for pipe 0x%x\n", pipe);
292 if (usb_stor_clear_halt(us, pipe) < 0)
293 return USB_STOR_XFER_ERROR;
294 return USB_STOR_XFER_STALLED;
295
296 /* babble - the device tried to send more than we wanted to read */
297 case -EOVERFLOW:
298 US_DEBUGP("-- babble\n");
299 return USB_STOR_XFER_LONG;
300
301 /* the transfer was cancelled by abort, disconnect, or timeout */
302 case -ECONNRESET:
303 US_DEBUGP("-- transfer cancelled\n");
304 return USB_STOR_XFER_ERROR;
305
306 /* short scatter-gather read transfer */
307 case -EREMOTEIO:
308 US_DEBUGP("-- short read transfer\n");
309 return USB_STOR_XFER_SHORT;
310
311 /* abort or disconnect in progress */
312 case -EIO:
313 US_DEBUGP("-- abort or disconnect in progress\n");
314 return USB_STOR_XFER_ERROR;
315
316 /* the catch-all error case */
317 default:
318 US_DEBUGP("-- unknown error\n");
319 return USB_STOR_XFER_ERROR;
320 }
321}
322
323/*
324 * Transfer one control message, without timeouts, but allowing early
325 * termination. Return codes are USB_STOR_XFER_xxx.
326 */
327int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe,
328 u8 request, u8 requesttype, u16 value, u16 index,
329 void *data, u16 size)
330{
331 int result;
332
333 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
334 __func__, request, requesttype,
335 value, index, size);
336
337 /* fill in the devrequest structure */
338 us->cr->bRequestType = requesttype;
339 us->cr->bRequest = request;
340 us->cr->wValue = cpu_to_le16(value);
341 us->cr->wIndex = cpu_to_le16(index);
342 us->cr->wLength = cpu_to_le16(size);
343
344 /* fill and submit the URB */
345 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe,
346 (unsigned char*) us->cr, data, size,
347 usb_stor_blocking_completion, NULL);
348 result = usb_stor_msg_common(us, 0);
349
350 return interpret_urb_result(us, pipe, size, result,
351 us->current_urb->actual_length);
352}
353EXPORT_SYMBOL_GPL(usb_stor_ctrl_transfer);
354
355/*
356 * Receive one interrupt buffer, without timeouts, but allowing early
357 * termination. Return codes are USB_STOR_XFER_xxx.
358 *
359 * This routine always uses us->recv_intr_pipe as the pipe and
360 * us->ep_bInterval as the interrupt interval.
361 */
362static int usb_stor_intr_transfer(struct us_data *us, void *buf,
363 unsigned int length)
364{
365 int result;
366 unsigned int pipe = us->recv_intr_pipe;
367 unsigned int maxp;
368
369 US_DEBUGP("%s: xfer %u bytes\n", __func__, length);
370
371 /* calculate the max packet size */
372 maxp = usb_maxpacket(us->pusb_dev, pipe, usb_pipeout(pipe));
373 if (maxp > length)
374 maxp = length;
375
376 /* fill and submit the URB */
377 usb_fill_int_urb(us->current_urb, us->pusb_dev, pipe, buf,
378 maxp, usb_stor_blocking_completion, NULL,
379 us->ep_bInterval);
380 result = usb_stor_msg_common(us, 0);
381
382 return interpret_urb_result(us, pipe, length, result,
383 us->current_urb->actual_length);
384}
385
386/*
387 * Transfer one buffer via bulk pipe, without timeouts, but allowing early
388 * termination. Return codes are USB_STOR_XFER_xxx. If the bulk pipe
389 * stalls during the transfer, the halt is automatically cleared.
390 */
391int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe,
392 void *buf, unsigned int length, unsigned int *act_len)
393{
394 int result;
395
396 US_DEBUGP("%s: xfer %u bytes\n", __func__, length);
397
398 /* fill and submit the URB */
399 usb_fill_bulk_urb(us->current_urb, us->pusb_dev, pipe, buf, length,
400 usb_stor_blocking_completion, NULL);
401 result = usb_stor_msg_common(us, 0);
402
403 /* store the actual length of the data transferred */
404 if (act_len)
405 *act_len = us->current_urb->actual_length;
406 return interpret_urb_result(us, pipe, length, result,
407 us->current_urb->actual_length);
408}
409EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_buf);
410
411/*
412 * Transfer a scatter-gather list via bulk transfer
413 *
414 * This function does basically the same thing as usb_stor_bulk_transfer_buf()
415 * above, but it uses the usbcore scatter-gather library.
416 */
417static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
418 struct scatterlist *sg, int num_sg, unsigned int length,
419 unsigned int *act_len)
420{
421 int result;
422
423 /* don't submit s-g requests during abort processing */
424 if (test_bit(US_FLIDX_ABORTING, &us->dflags))
425 return USB_STOR_XFER_ERROR;
426
427 /* initialize the scatter-gather request block */
428 US_DEBUGP("%s: xfer %u bytes, %d entries\n", __func__,
429 length, num_sg);
430 result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0,
431 sg, num_sg, length, GFP_NOIO);
432 if (result) {
433 US_DEBUGP("usb_sg_init returned %d\n", result);
434 return USB_STOR_XFER_ERROR;
435 }
436
437 /* since the block has been initialized successfully, it's now
438 * okay to cancel it */
439 set_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
440
441 /* did an abort occur during the submission? */
442 if (test_bit(US_FLIDX_ABORTING, &us->dflags)) {
443
444 /* cancel the request, if it hasn't been cancelled already */
445 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
446 US_DEBUGP("-- cancelling sg request\n");
447 usb_sg_cancel(&us->current_sg);
448 }
449 }
450
451 /* wait for the completion of the transfer */
452 usb_sg_wait(&us->current_sg);
453 clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
454
455 result = us->current_sg.status;
456 if (act_len)
457 *act_len = us->current_sg.bytes;
458 return interpret_urb_result(us, pipe, length, result,
459 us->current_sg.bytes);
460}
461
462/*
463 * Common used function. Transfer a complete command
464 * via usb_stor_bulk_transfer_sglist() above. Set cmnd resid
465 */
466int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe,
467 struct scsi_cmnd* srb)
468{
469 unsigned int partial;
470 int result = usb_stor_bulk_transfer_sglist(us, pipe, scsi_sglist(srb),
471 scsi_sg_count(srb), scsi_bufflen(srb),
472 &partial);
473
474 scsi_set_resid(srb, scsi_bufflen(srb) - partial);
475 return result;
476}
477EXPORT_SYMBOL_GPL(usb_stor_bulk_srb);
478
479/*
480 * Transfer an entire SCSI command's worth of data payload over the bulk
481 * pipe.
482 *
483 * Note that this uses usb_stor_bulk_transfer_buf() and
484 * usb_stor_bulk_transfer_sglist() to achieve its goals --
485 * this function simply determines whether we're going to use
486 * scatter-gather or not, and acts appropriately.
487 */
488int usb_stor_bulk_transfer_sg(struct us_data* us, unsigned int pipe,
489 void *buf, unsigned int length_left, int use_sg, int *residual)
490{
491 int result;
492 unsigned int partial;
493
494 /* are we scatter-gathering? */
495 if (use_sg) {
496 /* use the usb core scatter-gather primitives */
497 result = usb_stor_bulk_transfer_sglist(us, pipe,
498 (struct scatterlist *) buf, use_sg,
499 length_left, &partial);
500 length_left -= partial;
501 } else {
502 /* no scatter-gather, just make the request */
503 result = usb_stor_bulk_transfer_buf(us, pipe, buf,
504 length_left, &partial);
505 length_left -= partial;
506 }
507
508 /* store the residual and return the error code */
509 if (residual)
510 *residual = length_left;
511 return result;
512}
513EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_sg);
514
515/***********************************************************************
516 * Transport routines
517 ***********************************************************************/
518
519/* There are so many devices that report the capacity incorrectly,
520 * this routine was written to counteract some of the resulting
521 * problems.
522 */
523static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb)
524{
525 struct gendisk *disk;
526 struct scsi_disk *sdkp;
527 u32 sector;
528
529 /* To Report "Medium Error: Record Not Found */
530 static unsigned char record_not_found[18] = {
531 [0] = 0x70, /* current error */
532 [2] = MEDIUM_ERROR, /* = 0x03 */
533 [7] = 0x0a, /* additional length */
534 [12] = 0x14 /* Record Not Found */
535 };
536
537 /* If last-sector problems can't occur, whether because the
538 * capacity was already decremented or because the device is
539 * known to report the correct capacity, then we don't need
540 * to do anything.
541 */
542 if (!us->use_last_sector_hacks)
543 return;
544
545 /* Was this command a READ(10) or a WRITE(10)? */
546 if (srb->cmnd[0] != READ_10 && srb->cmnd[0] != WRITE_10)
547 goto done;
548
549 /* Did this command access the last sector? */
550 sector = (srb->cmnd[2] << 24) | (srb->cmnd[3] << 16) |
551 (srb->cmnd[4] << 8) | (srb->cmnd[5]);
552 disk = srb->request->rq_disk;
553 if (!disk)
554 goto done;
555 sdkp = scsi_disk(disk);
556 if (!sdkp)
557 goto done;
558 if (sector + 1 != sdkp->capacity)
559 goto done;
560
561 if (srb->result == SAM_STAT_GOOD && scsi_get_resid(srb) == 0) {
562
563 /* The command succeeded. We know this device doesn't
564 * have the last-sector bug, so stop checking it.
565 */
566 us->use_last_sector_hacks = 0;
567
568 } else {
569 /* The command failed. Allow up to 3 retries in case this
570 * is some normal sort of failure. After that, assume the
571 * capacity is wrong and we're trying to access the sector
572 * beyond the end. Replace the result code and sense data
573 * with values that will cause the SCSI core to fail the
574 * command immediately, instead of going into an infinite
575 * (or even just a very long) retry loop.
576 */
577 if (++us->last_sector_retries < 3)
578 return;
579 srb->result = SAM_STAT_CHECK_CONDITION;
580 memcpy(srb->sense_buffer, record_not_found,
581 sizeof(record_not_found));
582 }
583
584 done:
585 /* Don't reset the retry counter for TEST UNIT READY commands,
586 * because they get issued after device resets which might be
587 * caused by a failed last-sector access.
588 */
589 if (srb->cmnd[0] != TEST_UNIT_READY)
590 us->last_sector_retries = 0;
591}
592
593/* Invoke the transport and basic error-handling/recovery methods
594 *
595 * This is used by the protocol layers to actually send the message to
596 * the device and receive the response.
597 */
598void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
599{
600 int need_auto_sense;
601 int result;
602
603 /* send the command to the transport layer */
604 scsi_set_resid(srb, 0);
605 result = us->transport(srb, us);
606
607 /* if the command gets aborted by the higher layers, we need to
608 * short-circuit all other processing
609 */
610 if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
611 US_DEBUGP("-- command was aborted\n");
612 srb->result = DID_ABORT << 16;
613 goto Handle_Errors;
614 }
615
616 /* if there is a transport error, reset and don't auto-sense */
617 if (result == USB_STOR_TRANSPORT_ERROR) {
618 US_DEBUGP("-- transport indicates error, resetting\n");
619 srb->result = DID_ERROR << 16;
620 goto Handle_Errors;
621 }
622
623 /* if the transport provided its own sense data, don't auto-sense */
624 if (result == USB_STOR_TRANSPORT_NO_SENSE) {
625 srb->result = SAM_STAT_CHECK_CONDITION;
626 last_sector_hacks(us, srb);
627 return;
628 }
629
630 srb->result = SAM_STAT_GOOD;
631
632 /* Determine if we need to auto-sense
633 *
634 * I normally don't use a flag like this, but it's almost impossible
635 * to understand what's going on here if I don't.
636 */
637 need_auto_sense = 0;
638
639 /*
640 * If we're running the CB transport, which is incapable
641 * of determining status on its own, we will auto-sense
642 * unless the operation involved a data-in transfer. Devices
643 * can signal most data-in errors by stalling the bulk-in pipe.
644 */
645 if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_DPCM_USB) &&
646 srb->sc_data_direction != DMA_FROM_DEVICE) {
647 US_DEBUGP("-- CB transport device requiring auto-sense\n");
648 need_auto_sense = 1;
649 }
650
651 /*
652 * If we have a failure, we're going to do a REQUEST_SENSE
653 * automatically. Note that we differentiate between a command
654 * "failure" and an "error" in the transport mechanism.
655 */
656 if (result == USB_STOR_TRANSPORT_FAILED) {
657 US_DEBUGP("-- transport indicates command failure\n");
658 need_auto_sense = 1;
659 }
660
661 /*
662 * Determine if this device is SAT by seeing if the
663 * command executed successfully. Otherwise we'll have
664 * to wait for at least one CHECK_CONDITION to determine
665 * SANE_SENSE support
666 */
667 if (unlikely((srb->cmnd[0] == ATA_16 || srb->cmnd[0] == ATA_12) &&
668 result == USB_STOR_TRANSPORT_GOOD &&
669 !(us->fflags & US_FL_SANE_SENSE) &&
670 !(us->fflags & US_FL_BAD_SENSE) &&
671 !(srb->cmnd[2] & 0x20))) {
672 US_DEBUGP("-- SAT supported, increasing auto-sense\n");
673 us->fflags |= US_FL_SANE_SENSE;
674 }
675
676 /*
677 * A short transfer on a command where we don't expect it
678 * is unusual, but it doesn't mean we need to auto-sense.
679 */
680 if ((scsi_get_resid(srb) > 0) &&
681 !((srb->cmnd[0] == REQUEST_SENSE) ||
682 (srb->cmnd[0] == INQUIRY) ||
683 (srb->cmnd[0] == MODE_SENSE) ||
684 (srb->cmnd[0] == LOG_SENSE) ||
685 (srb->cmnd[0] == MODE_SENSE_10))) {
686 US_DEBUGP("-- unexpectedly short transfer\n");
687 }
688
689 /* Now, if we need to do the auto-sense, let's do it */
690 if (need_auto_sense) {
691 int temp_result;
692 struct scsi_eh_save ses;
693 int sense_size = US_SENSE_SIZE;
694
695 /* device supports and needs bigger sense buffer */
696 if (us->fflags & US_FL_SANE_SENSE)
697 sense_size = ~0;
698Retry_Sense:
699 US_DEBUGP("Issuing auto-REQUEST_SENSE\n");
700
701 scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sense_size);
702
703 /* FIXME: we must do the protocol translation here */
704 if (us->subclass == USB_SC_RBC || us->subclass == USB_SC_SCSI ||
705 us->subclass == USB_SC_CYP_ATACB)
706 srb->cmd_len = 6;
707 else
708 srb->cmd_len = 12;
709
710 /* issue the auto-sense command */
711 scsi_set_resid(srb, 0);
712 temp_result = us->transport(us->srb, us);
713
714 /* let's clean up right away */
715 scsi_eh_restore_cmnd(srb, &ses);
716
717 if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
718 US_DEBUGP("-- auto-sense aborted\n");
719 srb->result = DID_ABORT << 16;
720
721 /* If SANE_SENSE caused this problem, disable it */
722 if (sense_size != US_SENSE_SIZE) {
723 us->fflags &= ~US_FL_SANE_SENSE;
724 us->fflags |= US_FL_BAD_SENSE;
725 }
726 goto Handle_Errors;
727 }
728
729 /* Some devices claim to support larger sense but fail when
730 * trying to request it. When a transport failure happens
731 * using US_FS_SANE_SENSE, we always retry with a standard
732 * (small) sense request. This fixes some USB GSM modems
733 */
734 if (temp_result == USB_STOR_TRANSPORT_FAILED &&
735 sense_size != US_SENSE_SIZE) {
736 US_DEBUGP("-- auto-sense failure, retry small sense\n");
737 sense_size = US_SENSE_SIZE;
738 us->fflags &= ~US_FL_SANE_SENSE;
739 us->fflags |= US_FL_BAD_SENSE;
740 goto Retry_Sense;
741 }
742
743 /* Other failures */
744 if (temp_result != USB_STOR_TRANSPORT_GOOD) {
745 US_DEBUGP("-- auto-sense failure\n");
746
747 /* we skip the reset if this happens to be a
748 * multi-target device, since failure of an
749 * auto-sense is perfectly valid
750 */
751 srb->result = DID_ERROR << 16;
752 if (!(us->fflags & US_FL_SCM_MULT_TARG))
753 goto Handle_Errors;
754 return;
755 }
756
757 /* If the sense data returned is larger than 18-bytes then we
758 * assume this device supports requesting more in the future.
759 * The response code must be 70h through 73h inclusive.
760 */
761 if (srb->sense_buffer[7] > (US_SENSE_SIZE - 8) &&
762 !(us->fflags & US_FL_SANE_SENSE) &&
763 !(us->fflags & US_FL_BAD_SENSE) &&
764 (srb->sense_buffer[0] & 0x7C) == 0x70) {
765 US_DEBUGP("-- SANE_SENSE support enabled\n");
766 us->fflags |= US_FL_SANE_SENSE;
767
768 /* Indicate to the user that we truncated their sense
769 * because we didn't know it supported larger sense.
770 */
771 US_DEBUGP("-- Sense data truncated to %i from %i\n",
772 US_SENSE_SIZE,
773 srb->sense_buffer[7] + 8);
774 srb->sense_buffer[7] = (US_SENSE_SIZE - 8);
775 }
776
777 US_DEBUGP("-- Result from auto-sense is %d\n", temp_result);
778 US_DEBUGP("-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n",
779 srb->sense_buffer[0],
780 srb->sense_buffer[2] & 0xf,
781 srb->sense_buffer[12],
782 srb->sense_buffer[13]);
783#ifdef CONFIG_USB_STORAGE_DEBUG
784 usb_stor_show_sense(
785 srb->sense_buffer[2] & 0xf,
786 srb->sense_buffer[12],
787 srb->sense_buffer[13]);
788#endif
789
790 /* set the result so the higher layers expect this data */
791 srb->result = SAM_STAT_CHECK_CONDITION;
792
793 /* We often get empty sense data. This could indicate that
794 * everything worked or that there was an unspecified
795 * problem. We have to decide which.
796 */
797 if ( /* Filemark 0, ignore EOM, ILI 0, no sense */
798 (srb->sense_buffer[2] & 0xaf) == 0 &&
799 /* No ASC or ASCQ */
800 srb->sense_buffer[12] == 0 &&
801 srb->sense_buffer[13] == 0) {
802
803 /* If things are really okay, then let's show that.
804 * Zero out the sense buffer so the higher layers
805 * won't realize we did an unsolicited auto-sense.
806 */
807 if (result == USB_STOR_TRANSPORT_GOOD) {
808 srb->result = SAM_STAT_GOOD;
809 srb->sense_buffer[0] = 0x0;
810
811 /* If there was a problem, report an unspecified
812 * hardware error to prevent the higher layers from
813 * entering an infinite retry loop.
814 */
815 } else {
816 srb->result = DID_ERROR << 16;
817 srb->sense_buffer[2] = HARDWARE_ERROR;
818 }
819 }
820 }
821
822 /*
823 * Some devices don't work or return incorrect data the first
824 * time they get a READ(10) command, or for the first READ(10)
825 * after a media change. If the INITIAL_READ10 flag is set,
826 * keep track of whether READ(10) commands succeed. If the
827 * previous one succeeded and this one failed, set the REDO_READ10
828 * flag to force a retry.
829 */
830 if (unlikely((us->fflags & US_FL_INITIAL_READ10) &&
831 srb->cmnd[0] == READ_10)) {
832 if (srb->result == SAM_STAT_GOOD) {
833 set_bit(US_FLIDX_READ10_WORKED, &us->dflags);
834 } else if (test_bit(US_FLIDX_READ10_WORKED, &us->dflags)) {
835 clear_bit(US_FLIDX_READ10_WORKED, &us->dflags);
836 set_bit(US_FLIDX_REDO_READ10, &us->dflags);
837 }
838
839 /*
840 * Next, if the REDO_READ10 flag is set, return a result
841 * code that will cause the SCSI core to retry the READ(10)
842 * command immediately.
843 */
844 if (test_bit(US_FLIDX_REDO_READ10, &us->dflags)) {
845 clear_bit(US_FLIDX_REDO_READ10, &us->dflags);
846 srb->result = DID_IMM_RETRY << 16;
847 srb->sense_buffer[0] = 0;
848 }
849 }
850
851 /* Did we transfer less than the minimum amount required? */
852 if ((srb->result == SAM_STAT_GOOD || srb->sense_buffer[2] == 0) &&
853 scsi_bufflen(srb) - scsi_get_resid(srb) < srb->underflow)
854 srb->result = DID_ERROR << 16;
855
856 last_sector_hacks(us, srb);
857 return;
858
859 /* Error and abort processing: try to resynchronize with the device
860 * by issuing a port reset. If that fails, try a class-specific
861 * device reset. */
862 Handle_Errors:
863
864 /* Set the RESETTING bit, and clear the ABORTING bit so that
865 * the reset may proceed. */
866 scsi_lock(us_to_host(us));
867 set_bit(US_FLIDX_RESETTING, &us->dflags);
868 clear_bit(US_FLIDX_ABORTING, &us->dflags);
869 scsi_unlock(us_to_host(us));
870
871 /* We must release the device lock because the pre_reset routine
872 * will want to acquire it. */
873 mutex_unlock(&us->dev_mutex);
874 result = usb_stor_port_reset(us);
875 mutex_lock(&us->dev_mutex);
876
877 if (result < 0) {
878 scsi_lock(us_to_host(us));
879 usb_stor_report_device_reset(us);
880 scsi_unlock(us_to_host(us));
881 us->transport_reset(us);
882 }
883 clear_bit(US_FLIDX_RESETTING, &us->dflags);
884 last_sector_hacks(us, srb);
885}
886
887/* Stop the current URB transfer */
888void usb_stor_stop_transport(struct us_data *us)
889{
890 US_DEBUGP("%s called\n", __func__);
891
892 /* If the state machine is blocked waiting for an URB,
893 * let's wake it up. The test_and_clear_bit() call
894 * guarantees that if a URB has just been submitted,
895 * it won't be cancelled more than once. */
896 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
897 US_DEBUGP("-- cancelling URB\n");
898 usb_unlink_urb(us->current_urb);
899 }
900
901 /* If we are waiting for a scatter-gather operation, cancel it. */
902 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
903 US_DEBUGP("-- cancelling sg request\n");
904 usb_sg_cancel(&us->current_sg);
905 }
906}
907
908/*
909 * Control/Bulk and Control/Bulk/Interrupt transport
910 */
911
912int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us)
913{
914 unsigned int transfer_length = scsi_bufflen(srb);
915 unsigned int pipe = 0;
916 int result;
917
918 /* COMMAND STAGE */
919 /* let's send the command via the control pipe */
920 result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe,
921 US_CBI_ADSC,
922 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
923 us->ifnum, srb->cmnd, srb->cmd_len);
924
925 /* check the return code for the command */
926 US_DEBUGP("Call to usb_stor_ctrl_transfer() returned %d\n", result);
927
928 /* if we stalled the command, it means command failed */
929 if (result == USB_STOR_XFER_STALLED) {
930 return USB_STOR_TRANSPORT_FAILED;
931 }
932
933 /* Uh oh... serious problem here */
934 if (result != USB_STOR_XFER_GOOD) {
935 return USB_STOR_TRANSPORT_ERROR;
936 }
937
938 /* DATA STAGE */
939 /* transfer the data payload for this command, if one exists*/
940 if (transfer_length) {
941 pipe = srb->sc_data_direction == DMA_FROM_DEVICE ?
942 us->recv_bulk_pipe : us->send_bulk_pipe;
943 result = usb_stor_bulk_srb(us, pipe, srb);
944 US_DEBUGP("CBI data stage result is 0x%x\n", result);
945
946 /* if we stalled the data transfer it means command failed */
947 if (result == USB_STOR_XFER_STALLED)
948 return USB_STOR_TRANSPORT_FAILED;
949 if (result > USB_STOR_XFER_STALLED)
950 return USB_STOR_TRANSPORT_ERROR;
951 }
952
953 /* STATUS STAGE */
954
955 /* NOTE: CB does not have a status stage. Silly, I know. So
956 * we have to catch this at a higher level.
957 */
958 if (us->protocol != USB_PR_CBI)
959 return USB_STOR_TRANSPORT_GOOD;
960
961 result = usb_stor_intr_transfer(us, us->iobuf, 2);
962 US_DEBUGP("Got interrupt data (0x%x, 0x%x)\n",
963 us->iobuf[0], us->iobuf[1]);
964 if (result != USB_STOR_XFER_GOOD)
965 return USB_STOR_TRANSPORT_ERROR;
966
967 /* UFI gives us ASC and ASCQ, like a request sense
968 *
969 * REQUEST_SENSE and INQUIRY don't affect the sense data on UFI
970 * devices, so we ignore the information for those commands. Note
971 * that this means we could be ignoring a real error on these
972 * commands, but that can't be helped.
973 */
974 if (us->subclass == USB_SC_UFI) {
975 if (srb->cmnd[0] == REQUEST_SENSE ||
976 srb->cmnd[0] == INQUIRY)
977 return USB_STOR_TRANSPORT_GOOD;
978 if (us->iobuf[0])
979 goto Failed;
980 return USB_STOR_TRANSPORT_GOOD;
981 }
982
983 /* If not UFI, we interpret the data as a result code
984 * The first byte should always be a 0x0.
985 *
986 * Some bogus devices don't follow that rule. They stuff the ASC
987 * into the first byte -- so if it's non-zero, call it a failure.
988 */
989 if (us->iobuf[0]) {
990 US_DEBUGP("CBI IRQ data showed reserved bType 0x%x\n",
991 us->iobuf[0]);
992 goto Failed;
993
994 }
995
996 /* The second byte & 0x0F should be 0x0 for good, otherwise error */
997 switch (us->iobuf[1] & 0x0F) {
998 case 0x00:
999 return USB_STOR_TRANSPORT_GOOD;
1000 case 0x01:
1001 goto Failed;
1002 }
1003 return USB_STOR_TRANSPORT_ERROR;
1004
1005 /* the CBI spec requires that the bulk pipe must be cleared
1006 * following any data-in/out command failure (section 2.4.3.1.3)
1007 */
1008 Failed:
1009 if (pipe)
1010 usb_stor_clear_halt(us, pipe);
1011 return USB_STOR_TRANSPORT_FAILED;
1012}
1013EXPORT_SYMBOL_GPL(usb_stor_CB_transport);
1014
1015/*
1016 * Bulk only transport
1017 */
1018
1019/* Determine what the maximum LUN supported is */
1020int usb_stor_Bulk_max_lun(struct us_data *us)
1021{
1022 int result;
1023
1024 /* issue the command */
1025 us->iobuf[0] = 0;
1026 result = usb_stor_control_msg(us, us->recv_ctrl_pipe,
1027 US_BULK_GET_MAX_LUN,
1028 USB_DIR_IN | USB_TYPE_CLASS |
1029 USB_RECIP_INTERFACE,
1030 0, us->ifnum, us->iobuf, 1, 10*HZ);
1031
1032 US_DEBUGP("GetMaxLUN command result is %d, data is %d\n",
1033 result, us->iobuf[0]);
1034
1035 /* if we have a successful request, return the result */
1036 if (result > 0)
1037 return us->iobuf[0];
1038
1039 /*
1040 * Some devices don't like GetMaxLUN. They may STALL the control
1041 * pipe, they may return a zero-length result, they may do nothing at
1042 * all and timeout, or they may fail in even more bizarrely creative
1043 * ways. In these cases the best approach is to use the default
1044 * value: only one LUN.
1045 */
1046 return 0;
1047}
1048
1049int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
1050{
1051 struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf;
1052 struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf;
1053 unsigned int transfer_length = scsi_bufflen(srb);
1054 unsigned int residue;
1055 int result;
1056 int fake_sense = 0;
1057 unsigned int cswlen;
1058 unsigned int cbwlen = US_BULK_CB_WRAP_LEN;
1059
1060 /* Take care of BULK32 devices; set extra byte to 0 */
1061 if (unlikely(us->fflags & US_FL_BULK32)) {
1062 cbwlen = 32;
1063 us->iobuf[31] = 0;
1064 }
1065
1066 /* set up the command wrapper */
1067 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
1068 bcb->DataTransferLength = cpu_to_le32(transfer_length);
1069 bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ? 1 << 7 : 0;
1070 bcb->Tag = ++us->tag;
1071 bcb->Lun = srb->device->lun;
1072 if (us->fflags & US_FL_SCM_MULT_TARG)
1073 bcb->Lun |= srb->device->id << 4;
1074 bcb->Length = srb->cmd_len;
1075
1076 /* copy the command payload */
1077 memset(bcb->CDB, 0, sizeof(bcb->CDB));
1078 memcpy(bcb->CDB, srb->cmnd, bcb->Length);
1079
1080 /* send it to out endpoint */
1081 US_DEBUGP("Bulk Command S 0x%x T 0x%x L %d F %d Trg %d LUN %d CL %d\n",
1082 le32_to_cpu(bcb->Signature), bcb->Tag,
1083 le32_to_cpu(bcb->DataTransferLength), bcb->Flags,
1084 (bcb->Lun >> 4), (bcb->Lun & 0x0F),
1085 bcb->Length);
1086 result = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
1087 bcb, cbwlen, NULL);
1088 US_DEBUGP("Bulk command transfer result=%d\n", result);
1089 if (result != USB_STOR_XFER_GOOD)
1090 return USB_STOR_TRANSPORT_ERROR;
1091
1092 /* DATA STAGE */
1093 /* send/receive data payload, if there is any */
1094
1095 /* Some USB-IDE converter chips need a 100us delay between the
1096 * command phase and the data phase. Some devices need a little
1097 * more than that, probably because of clock rate inaccuracies. */
1098 if (unlikely(us->fflags & US_FL_GO_SLOW))
1099 udelay(125);
1100
1101 if (transfer_length) {
1102 unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ?
1103 us->recv_bulk_pipe : us->send_bulk_pipe;
1104 result = usb_stor_bulk_srb(us, pipe, srb);
1105 US_DEBUGP("Bulk data transfer result 0x%x\n", result);
1106 if (result == USB_STOR_XFER_ERROR)
1107 return USB_STOR_TRANSPORT_ERROR;
1108
1109 /* If the device tried to send back more data than the
1110 * amount requested, the spec requires us to transfer
1111 * the CSW anyway. Since there's no point retrying the
1112 * the command, we'll return fake sense data indicating
1113 * Illegal Request, Invalid Field in CDB.
1114 */
1115 if (result == USB_STOR_XFER_LONG)
1116 fake_sense = 1;
1117 }
1118
1119 /* See flow chart on pg 15 of the Bulk Only Transport spec for
1120 * an explanation of how this code works.
1121 */
1122
1123 /* get CSW for device status */
1124 US_DEBUGP("Attempting to get CSW...\n");
1125 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1126 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
1127
1128 /* Some broken devices add unnecessary zero-length packets to the
1129 * end of their data transfers. Such packets show up as 0-length
1130 * CSWs. If we encounter such a thing, try to read the CSW again.
1131 */
1132 if (result == USB_STOR_XFER_SHORT && cswlen == 0) {
1133 US_DEBUGP("Received 0-length CSW; retrying...\n");
1134 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1135 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
1136 }
1137
1138 /* did the attempt to read the CSW fail? */
1139 if (result == USB_STOR_XFER_STALLED) {
1140
1141 /* get the status again */
1142 US_DEBUGP("Attempting to get CSW (2nd try)...\n");
1143 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1144 bcs, US_BULK_CS_WRAP_LEN, NULL);
1145 }
1146
1147 /* if we still have a failure at this point, we're in trouble */
1148 US_DEBUGP("Bulk status result = %d\n", result);
1149 if (result != USB_STOR_XFER_GOOD)
1150 return USB_STOR_TRANSPORT_ERROR;
1151
1152 /* check bulk status */
1153 residue = le32_to_cpu(bcs->Residue);
1154 US_DEBUGP("Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n",
1155 le32_to_cpu(bcs->Signature), bcs->Tag,
1156 residue, bcs->Status);
1157 if (!(bcs->Tag == us->tag || (us->fflags & US_FL_BULK_IGNORE_TAG)) ||
1158 bcs->Status > US_BULK_STAT_PHASE) {
1159 US_DEBUGP("Bulk logical error\n");
1160 return USB_STOR_TRANSPORT_ERROR;
1161 }
1162
1163 /* Some broken devices report odd signatures, so we do not check them
1164 * for validity against the spec. We store the first one we see,
1165 * and check subsequent transfers for validity against this signature.
1166 */
1167 if (!us->bcs_signature) {
1168 us->bcs_signature = bcs->Signature;
1169 if (us->bcs_signature != cpu_to_le32(US_BULK_CS_SIGN))
1170 US_DEBUGP("Learnt BCS signature 0x%08X\n",
1171 le32_to_cpu(us->bcs_signature));
1172 } else if (bcs->Signature != us->bcs_signature) {
1173 US_DEBUGP("Signature mismatch: got %08X, expecting %08X\n",
1174 le32_to_cpu(bcs->Signature),
1175 le32_to_cpu(us->bcs_signature));
1176 return USB_STOR_TRANSPORT_ERROR;
1177 }
1178
1179 /* try to compute the actual residue, based on how much data
1180 * was really transferred and what the device tells us */
1181 if (residue && !(us->fflags & US_FL_IGNORE_RESIDUE)) {
1182
1183 /* Heuristically detect devices that generate bogus residues
1184 * by seeing what happens with INQUIRY and READ CAPACITY
1185 * commands.
1186 */
1187 if (bcs->Status == US_BULK_STAT_OK &&
1188 scsi_get_resid(srb) == 0 &&
1189 ((srb->cmnd[0] == INQUIRY &&
1190 transfer_length == 36) ||
1191 (srb->cmnd[0] == READ_CAPACITY &&
1192 transfer_length == 8))) {
1193 us->fflags |= US_FL_IGNORE_RESIDUE;
1194
1195 } else {
1196 residue = min(residue, transfer_length);
1197 scsi_set_resid(srb, max(scsi_get_resid(srb),
1198 (int) residue));
1199 }
1200 }
1201
1202 /* based on the status code, we report good or bad */
1203 switch (bcs->Status) {
1204 case US_BULK_STAT_OK:
1205 /* device babbled -- return fake sense data */
1206 if (fake_sense) {
1207 memcpy(srb->sense_buffer,
1208 usb_stor_sense_invalidCDB,
1209 sizeof(usb_stor_sense_invalidCDB));
1210 return USB_STOR_TRANSPORT_NO_SENSE;
1211 }
1212
1213 /* command good -- note that data could be short */
1214 return USB_STOR_TRANSPORT_GOOD;
1215
1216 case US_BULK_STAT_FAIL:
1217 /* command failed */
1218 return USB_STOR_TRANSPORT_FAILED;
1219
1220 case US_BULK_STAT_PHASE:
1221 /* phase error -- note that a transport reset will be
1222 * invoked by the invoke_transport() function
1223 */
1224 return USB_STOR_TRANSPORT_ERROR;
1225 }
1226
1227 /* we should never get here, but if we do, we're in trouble */
1228 return USB_STOR_TRANSPORT_ERROR;
1229}
1230EXPORT_SYMBOL_GPL(usb_stor_Bulk_transport);
1231
1232/***********************************************************************
1233 * Reset routines
1234 ***********************************************************************/
1235
1236/* This is the common part of the device reset code.
1237 *
1238 * It's handy that every transport mechanism uses the control endpoint for
1239 * resets.
1240 *
1241 * Basically, we send a reset with a 5-second timeout, so we don't get
1242 * jammed attempting to do the reset.
1243 */
1244static int usb_stor_reset_common(struct us_data *us,
1245 u8 request, u8 requesttype,
1246 u16 value, u16 index, void *data, u16 size)
1247{
1248 int result;
1249 int result2;
1250
1251 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
1252 US_DEBUGP("No reset during disconnect\n");
1253 return -EIO;
1254 }
1255
1256 result = usb_stor_control_msg(us, us->send_ctrl_pipe,
1257 request, requesttype, value, index, data, size,
1258 5*HZ);
1259 if (result < 0) {
1260 US_DEBUGP("Soft reset failed: %d\n", result);
1261 return result;
1262 }
1263
1264 /* Give the device some time to recover from the reset,
1265 * but don't delay disconnect processing. */
1266 wait_event_interruptible_timeout(us->delay_wait,
1267 test_bit(US_FLIDX_DISCONNECTING, &us->dflags),
1268 HZ*6);
1269 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
1270 US_DEBUGP("Reset interrupted by disconnect\n");
1271 return -EIO;
1272 }
1273
1274 US_DEBUGP("Soft reset: clearing bulk-in endpoint halt\n");
1275 result = usb_stor_clear_halt(us, us->recv_bulk_pipe);
1276
1277 US_DEBUGP("Soft reset: clearing bulk-out endpoint halt\n");
1278 result2 = usb_stor_clear_halt(us, us->send_bulk_pipe);
1279
1280 /* return a result code based on the result of the clear-halts */
1281 if (result >= 0)
1282 result = result2;
1283 if (result < 0)
1284 US_DEBUGP("Soft reset failed\n");
1285 else
1286 US_DEBUGP("Soft reset done\n");
1287 return result;
1288}
1289
1290/* This issues a CB[I] Reset to the device in question
1291 */
1292#define CB_RESET_CMD_SIZE 12
1293
1294int usb_stor_CB_reset(struct us_data *us)
1295{
1296 US_DEBUGP("%s called\n", __func__);
1297
1298 memset(us->iobuf, 0xFF, CB_RESET_CMD_SIZE);
1299 us->iobuf[0] = SEND_DIAGNOSTIC;
1300 us->iobuf[1] = 4;
1301 return usb_stor_reset_common(us, US_CBI_ADSC,
1302 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1303 0, us->ifnum, us->iobuf, CB_RESET_CMD_SIZE);
1304}
1305EXPORT_SYMBOL_GPL(usb_stor_CB_reset);
1306
1307/* This issues a Bulk-only Reset to the device in question, including
1308 * clearing the subsequent endpoint halts that may occur.
1309 */
1310int usb_stor_Bulk_reset(struct us_data *us)
1311{
1312 US_DEBUGP("%s called\n", __func__);
1313
1314 return usb_stor_reset_common(us, US_BULK_RESET_REQUEST,
1315 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1316 0, us->ifnum, NULL, 0);
1317}
1318EXPORT_SYMBOL_GPL(usb_stor_Bulk_reset);
1319
1320/* Issue a USB port reset to the device. The caller must not hold
1321 * us->dev_mutex.
1322 */
1323int usb_stor_port_reset(struct us_data *us)
1324{
1325 int result;
1326
1327 /*for these devices we must use the class specific method */
1328 if (us->pusb_dev->quirks & USB_QUIRK_RESET_MORPHS)
1329 return -EPERM;
1330
1331 result = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
1332 if (result < 0)
1333 US_DEBUGP("unable to lock device for reset: %d\n", result);
1334 else {
1335 /* Were we disconnected while waiting for the lock? */
1336 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
1337 result = -EIO;
1338 US_DEBUGP("No reset during disconnect\n");
1339 } else {
1340 result = usb_reset_device(us->pusb_dev);
1341 US_DEBUGP("usb_reset_device returns %d\n",
1342 result);
1343 }
1344 usb_unlock_device(us->pusb_dev);
1345 }
1346 return result;
1347}
1/* Driver for USB Mass Storage compliant devices
2 *
3 * Current development and maintenance by:
4 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
5 *
6 * Developed with the assistance of:
7 * (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
8 * (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
9 * (c) 2002 Alan Stern <stern@rowland.org>
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/sched.h>
47#include <linux/gfp.h>
48#include <linux/errno.h>
49#include <linux/export.h>
50
51#include <linux/usb/quirks.h>
52
53#include <scsi/scsi.h>
54#include <scsi/scsi_eh.h>
55#include <scsi/scsi_device.h>
56
57#include "usb.h"
58#include "transport.h"
59#include "protocol.h"
60#include "scsiglue.h"
61#include "debug.h"
62
63#include <linux/blkdev.h>
64#include "../../scsi/sd.h"
65
66
67/***********************************************************************
68 * Data transfer routines
69 ***********************************************************************/
70
71/*
72 * This is subtle, so pay attention:
73 * ---------------------------------
74 * We're very concerned about races with a command abort. Hanging this code
75 * is a sure fire way to hang the kernel. (Note that this discussion applies
76 * only to transactions resulting from a scsi queued-command, since only
77 * these transactions are subject to a scsi abort. Other transactions, such
78 * as those occurring during device-specific initialization, must be handled
79 * by a separate code path.)
80 *
81 * The abort function (usb_storage_command_abort() in scsiglue.c) first
82 * sets the machine state and the ABORTING bit in us->dflags to prevent
83 * new URBs from being submitted. It then calls usb_stor_stop_transport()
84 * below, which atomically tests-and-clears the URB_ACTIVE bit in us->dflags
85 * to see if the current_urb needs to be stopped. Likewise, the SG_ACTIVE
86 * bit is tested to see if the current_sg scatter-gather request needs to be
87 * stopped. The timeout callback routine does much the same thing.
88 *
89 * When a disconnect occurs, the DISCONNECTING bit in us->dflags is set to
90 * prevent new URBs from being submitted, and usb_stor_stop_transport() is
91 * called to stop any ongoing requests.
92 *
93 * The submit function first verifies that the submitting is allowed
94 * (neither ABORTING nor DISCONNECTING bits are set) and that the submit
95 * completes without errors, and only then sets the URB_ACTIVE bit. This
96 * prevents the stop_transport() function from trying to cancel the URB
97 * while the submit call is underway. Next, the submit function must test
98 * the flags to see if an abort or disconnect occurred during the submission
99 * or before the URB_ACTIVE bit was set. If so, it's essential to cancel
100 * the URB if it hasn't been cancelled already (i.e., if the URB_ACTIVE bit
101 * is still set). Either way, the function must then wait for the URB to
102 * finish. Note that the URB can still be in progress even after a call to
103 * usb_unlink_urb() returns.
104 *
105 * The idea is that (1) once the ABORTING or DISCONNECTING bit is set,
106 * either the stop_transport() function or the submitting function
107 * is guaranteed to call usb_unlink_urb() for an active URB,
108 * and (2) test_and_clear_bit() prevents usb_unlink_urb() from being
109 * called more than once or from being called during usb_submit_urb().
110 */
111
112/* This is the completion handler which will wake us up when an URB
113 * completes.
114 */
115static void usb_stor_blocking_completion(struct urb *urb)
116{
117 struct completion *urb_done_ptr = urb->context;
118
119 complete(urb_done_ptr);
120}
121
122/* This is the common part of the URB message submission code
123 *
124 * All URBs from the usb-storage driver involved in handling a queued scsi
125 * command _must_ pass through this function (or something like it) for the
126 * abort mechanisms to work properly.
127 */
128static int usb_stor_msg_common(struct us_data *us, int timeout)
129{
130 struct completion urb_done;
131 long timeleft;
132 int status;
133
134 /* don't submit URBs during abort processing */
135 if (test_bit(US_FLIDX_ABORTING, &us->dflags))
136 return -EIO;
137
138 /* set up data structures for the wakeup system */
139 init_completion(&urb_done);
140
141 /* fill the common fields in the URB */
142 us->current_urb->context = &urb_done;
143 us->current_urb->transfer_flags = 0;
144
145 /* we assume that if transfer_buffer isn't us->iobuf then it
146 * hasn't been mapped for DMA. Yes, this is clunky, but it's
147 * easier than always having the caller tell us whether the
148 * transfer buffer has already been mapped. */
149 if (us->current_urb->transfer_buffer == us->iobuf)
150 us->current_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
151 us->current_urb->transfer_dma = us->iobuf_dma;
152
153 /* submit the URB */
154 status = usb_submit_urb(us->current_urb, GFP_NOIO);
155 if (status) {
156 /* something went wrong */
157 return status;
158 }
159
160 /* since the URB has been submitted successfully, it's now okay
161 * to cancel it */
162 set_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
163
164 /* did an abort occur during the submission? */
165 if (test_bit(US_FLIDX_ABORTING, &us->dflags)) {
166
167 /* cancel the URB, if it hasn't been cancelled already */
168 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
169 usb_stor_dbg(us, "-- cancelling URB\n");
170 usb_unlink_urb(us->current_urb);
171 }
172 }
173
174 /* wait for the completion of the URB */
175 timeleft = wait_for_completion_interruptible_timeout(
176 &urb_done, timeout ? : MAX_SCHEDULE_TIMEOUT);
177
178 clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
179
180 if (timeleft <= 0) {
181 usb_stor_dbg(us, "%s -- cancelling URB\n",
182 timeleft == 0 ? "Timeout" : "Signal");
183 usb_kill_urb(us->current_urb);
184 }
185
186 /* return the URB status */
187 return us->current_urb->status;
188}
189
190/*
191 * Transfer one control message, with timeouts, and allowing early
192 * termination. Return codes are usual -Exxx, *not* USB_STOR_XFER_xxx.
193 */
194int usb_stor_control_msg(struct us_data *us, unsigned int pipe,
195 u8 request, u8 requesttype, u16 value, u16 index,
196 void *data, u16 size, int timeout)
197{
198 int status;
199
200 usb_stor_dbg(us, "rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
201 request, requesttype, value, index, size);
202
203 /* fill in the devrequest structure */
204 us->cr->bRequestType = requesttype;
205 us->cr->bRequest = request;
206 us->cr->wValue = cpu_to_le16(value);
207 us->cr->wIndex = cpu_to_le16(index);
208 us->cr->wLength = cpu_to_le16(size);
209
210 /* fill and submit the URB */
211 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe,
212 (unsigned char*) us->cr, data, size,
213 usb_stor_blocking_completion, NULL);
214 status = usb_stor_msg_common(us, timeout);
215
216 /* return the actual length of the data transferred if no error */
217 if (status == 0)
218 status = us->current_urb->actual_length;
219 return status;
220}
221EXPORT_SYMBOL_GPL(usb_stor_control_msg);
222
223/* This is a version of usb_clear_halt() that allows early termination and
224 * doesn't read the status from the device -- this is because some devices
225 * crash their internal firmware when the status is requested after a halt.
226 *
227 * A definitive list of these 'bad' devices is too difficult to maintain or
228 * make complete enough to be useful. This problem was first observed on the
229 * Hagiwara FlashGate DUAL unit. However, bus traces reveal that neither
230 * MacOS nor Windows checks the status after clearing a halt.
231 *
232 * Since many vendors in this space limit their testing to interoperability
233 * with these two OSes, specification violations like this one are common.
234 */
235int usb_stor_clear_halt(struct us_data *us, unsigned int pipe)
236{
237 int result;
238 int endp = usb_pipeendpoint(pipe);
239
240 if (usb_pipein (pipe))
241 endp |= USB_DIR_IN;
242
243 result = usb_stor_control_msg(us, us->send_ctrl_pipe,
244 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
245 USB_ENDPOINT_HALT, endp,
246 NULL, 0, 3*HZ);
247
248 if (result >= 0)
249 usb_reset_endpoint(us->pusb_dev, endp);
250
251 usb_stor_dbg(us, "result = %d\n", result);
252 return result;
253}
254EXPORT_SYMBOL_GPL(usb_stor_clear_halt);
255
256
257/*
258 * Interpret the results of a URB transfer
259 *
260 * This function prints appropriate debugging messages, clears halts on
261 * non-control endpoints, and translates the status to the corresponding
262 * USB_STOR_XFER_xxx return code.
263 */
264static int interpret_urb_result(struct us_data *us, unsigned int pipe,
265 unsigned int length, int result, unsigned int partial)
266{
267 usb_stor_dbg(us, "Status code %d; transferred %u/%u\n",
268 result, partial, length);
269 switch (result) {
270
271 /* no error code; did we send all the data? */
272 case 0:
273 if (partial != length) {
274 usb_stor_dbg(us, "-- short transfer\n");
275 return USB_STOR_XFER_SHORT;
276 }
277
278 usb_stor_dbg(us, "-- transfer complete\n");
279 return USB_STOR_XFER_GOOD;
280
281 /* stalled */
282 case -EPIPE:
283 /* for control endpoints, (used by CB[I]) a stall indicates
284 * a failed command */
285 if (usb_pipecontrol(pipe)) {
286 usb_stor_dbg(us, "-- stall on control pipe\n");
287 return USB_STOR_XFER_STALLED;
288 }
289
290 /* for other sorts of endpoint, clear the stall */
291 usb_stor_dbg(us, "clearing endpoint halt for pipe 0x%x\n",
292 pipe);
293 if (usb_stor_clear_halt(us, pipe) < 0)
294 return USB_STOR_XFER_ERROR;
295 return USB_STOR_XFER_STALLED;
296
297 /* babble - the device tried to send more than we wanted to read */
298 case -EOVERFLOW:
299 usb_stor_dbg(us, "-- babble\n");
300 return USB_STOR_XFER_LONG;
301
302 /* the transfer was cancelled by abort, disconnect, or timeout */
303 case -ECONNRESET:
304 usb_stor_dbg(us, "-- transfer cancelled\n");
305 return USB_STOR_XFER_ERROR;
306
307 /* short scatter-gather read transfer */
308 case -EREMOTEIO:
309 usb_stor_dbg(us, "-- short read transfer\n");
310 return USB_STOR_XFER_SHORT;
311
312 /* abort or disconnect in progress */
313 case -EIO:
314 usb_stor_dbg(us, "-- abort or disconnect in progress\n");
315 return USB_STOR_XFER_ERROR;
316
317 /* the catch-all error case */
318 default:
319 usb_stor_dbg(us, "-- unknown error\n");
320 return USB_STOR_XFER_ERROR;
321 }
322}
323
324/*
325 * Transfer one control message, without timeouts, but allowing early
326 * termination. Return codes are USB_STOR_XFER_xxx.
327 */
328int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe,
329 u8 request, u8 requesttype, u16 value, u16 index,
330 void *data, u16 size)
331{
332 int result;
333
334 usb_stor_dbg(us, "rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
335 request, requesttype, value, index, size);
336
337 /* fill in the devrequest structure */
338 us->cr->bRequestType = requesttype;
339 us->cr->bRequest = request;
340 us->cr->wValue = cpu_to_le16(value);
341 us->cr->wIndex = cpu_to_le16(index);
342 us->cr->wLength = cpu_to_le16(size);
343
344 /* fill and submit the URB */
345 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe,
346 (unsigned char*) us->cr, data, size,
347 usb_stor_blocking_completion, NULL);
348 result = usb_stor_msg_common(us, 0);
349
350 return interpret_urb_result(us, pipe, size, result,
351 us->current_urb->actual_length);
352}
353EXPORT_SYMBOL_GPL(usb_stor_ctrl_transfer);
354
355/*
356 * Receive one interrupt buffer, without timeouts, but allowing early
357 * termination. Return codes are USB_STOR_XFER_xxx.
358 *
359 * This routine always uses us->recv_intr_pipe as the pipe and
360 * us->ep_bInterval as the interrupt interval.
361 */
362static int usb_stor_intr_transfer(struct us_data *us, void *buf,
363 unsigned int length)
364{
365 int result;
366 unsigned int pipe = us->recv_intr_pipe;
367 unsigned int maxp;
368
369 usb_stor_dbg(us, "xfer %u bytes\n", length);
370
371 /* calculate the max packet size */
372 maxp = usb_maxpacket(us->pusb_dev, pipe, usb_pipeout(pipe));
373 if (maxp > length)
374 maxp = length;
375
376 /* fill and submit the URB */
377 usb_fill_int_urb(us->current_urb, us->pusb_dev, pipe, buf,
378 maxp, usb_stor_blocking_completion, NULL,
379 us->ep_bInterval);
380 result = usb_stor_msg_common(us, 0);
381
382 return interpret_urb_result(us, pipe, length, result,
383 us->current_urb->actual_length);
384}
385
386/*
387 * Transfer one buffer via bulk pipe, without timeouts, but allowing early
388 * termination. Return codes are USB_STOR_XFER_xxx. If the bulk pipe
389 * stalls during the transfer, the halt is automatically cleared.
390 */
391int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe,
392 void *buf, unsigned int length, unsigned int *act_len)
393{
394 int result;
395
396 usb_stor_dbg(us, "xfer %u bytes\n", length);
397
398 /* fill and submit the URB */
399 usb_fill_bulk_urb(us->current_urb, us->pusb_dev, pipe, buf, length,
400 usb_stor_blocking_completion, NULL);
401 result = usb_stor_msg_common(us, 0);
402
403 /* store the actual length of the data transferred */
404 if (act_len)
405 *act_len = us->current_urb->actual_length;
406 return interpret_urb_result(us, pipe, length, result,
407 us->current_urb->actual_length);
408}
409EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_buf);
410
411/*
412 * Transfer a scatter-gather list via bulk transfer
413 *
414 * This function does basically the same thing as usb_stor_bulk_transfer_buf()
415 * above, but it uses the usbcore scatter-gather library.
416 */
417static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
418 struct scatterlist *sg, int num_sg, unsigned int length,
419 unsigned int *act_len)
420{
421 int result;
422
423 /* don't submit s-g requests during abort processing */
424 if (test_bit(US_FLIDX_ABORTING, &us->dflags))
425 return USB_STOR_XFER_ERROR;
426
427 /* initialize the scatter-gather request block */
428 usb_stor_dbg(us, "xfer %u bytes, %d entries\n", length, num_sg);
429 result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0,
430 sg, num_sg, length, GFP_NOIO);
431 if (result) {
432 usb_stor_dbg(us, "usb_sg_init returned %d\n", result);
433 return USB_STOR_XFER_ERROR;
434 }
435
436 /* since the block has been initialized successfully, it's now
437 * okay to cancel it */
438 set_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
439
440 /* did an abort occur during the submission? */
441 if (test_bit(US_FLIDX_ABORTING, &us->dflags)) {
442
443 /* cancel the request, if it hasn't been cancelled already */
444 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
445 usb_stor_dbg(us, "-- cancelling sg request\n");
446 usb_sg_cancel(&us->current_sg);
447 }
448 }
449
450 /* wait for the completion of the transfer */
451 usb_sg_wait(&us->current_sg);
452 clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
453
454 result = us->current_sg.status;
455 if (act_len)
456 *act_len = us->current_sg.bytes;
457 return interpret_urb_result(us, pipe, length, result,
458 us->current_sg.bytes);
459}
460
461/*
462 * Common used function. Transfer a complete command
463 * via usb_stor_bulk_transfer_sglist() above. Set cmnd resid
464 */
465int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe,
466 struct scsi_cmnd* srb)
467{
468 unsigned int partial;
469 int result = usb_stor_bulk_transfer_sglist(us, pipe, scsi_sglist(srb),
470 scsi_sg_count(srb), scsi_bufflen(srb),
471 &partial);
472
473 scsi_set_resid(srb, scsi_bufflen(srb) - partial);
474 return result;
475}
476EXPORT_SYMBOL_GPL(usb_stor_bulk_srb);
477
478/*
479 * Transfer an entire SCSI command's worth of data payload over the bulk
480 * pipe.
481 *
482 * Note that this uses usb_stor_bulk_transfer_buf() and
483 * usb_stor_bulk_transfer_sglist() to achieve its goals --
484 * this function simply determines whether we're going to use
485 * scatter-gather or not, and acts appropriately.
486 */
487int usb_stor_bulk_transfer_sg(struct us_data* us, unsigned int pipe,
488 void *buf, unsigned int length_left, int use_sg, int *residual)
489{
490 int result;
491 unsigned int partial;
492
493 /* are we scatter-gathering? */
494 if (use_sg) {
495 /* use the usb core scatter-gather primitives */
496 result = usb_stor_bulk_transfer_sglist(us, pipe,
497 (struct scatterlist *) buf, use_sg,
498 length_left, &partial);
499 length_left -= partial;
500 } else {
501 /* no scatter-gather, just make the request */
502 result = usb_stor_bulk_transfer_buf(us, pipe, buf,
503 length_left, &partial);
504 length_left -= partial;
505 }
506
507 /* store the residual and return the error code */
508 if (residual)
509 *residual = length_left;
510 return result;
511}
512EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_sg);
513
514/***********************************************************************
515 * Transport routines
516 ***********************************************************************/
517
518/* There are so many devices that report the capacity incorrectly,
519 * this routine was written to counteract some of the resulting
520 * problems.
521 */
522static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb)
523{
524 struct gendisk *disk;
525 struct scsi_disk *sdkp;
526 u32 sector;
527
528 /* To Report "Medium Error: Record Not Found */
529 static unsigned char record_not_found[18] = {
530 [0] = 0x70, /* current error */
531 [2] = MEDIUM_ERROR, /* = 0x03 */
532 [7] = 0x0a, /* additional length */
533 [12] = 0x14 /* Record Not Found */
534 };
535
536 /* If last-sector problems can't occur, whether because the
537 * capacity was already decremented or because the device is
538 * known to report the correct capacity, then we don't need
539 * to do anything.
540 */
541 if (!us->use_last_sector_hacks)
542 return;
543
544 /* Was this command a READ(10) or a WRITE(10)? */
545 if (srb->cmnd[0] != READ_10 && srb->cmnd[0] != WRITE_10)
546 goto done;
547
548 /* Did this command access the last sector? */
549 sector = (srb->cmnd[2] << 24) | (srb->cmnd[3] << 16) |
550 (srb->cmnd[4] << 8) | (srb->cmnd[5]);
551 disk = srb->request->rq_disk;
552 if (!disk)
553 goto done;
554 sdkp = scsi_disk(disk);
555 if (!sdkp)
556 goto done;
557 if (sector + 1 != sdkp->capacity)
558 goto done;
559
560 if (srb->result == SAM_STAT_GOOD && scsi_get_resid(srb) == 0) {
561
562 /* The command succeeded. We know this device doesn't
563 * have the last-sector bug, so stop checking it.
564 */
565 us->use_last_sector_hacks = 0;
566
567 } else {
568 /* The command failed. Allow up to 3 retries in case this
569 * is some normal sort of failure. After that, assume the
570 * capacity is wrong and we're trying to access the sector
571 * beyond the end. Replace the result code and sense data
572 * with values that will cause the SCSI core to fail the
573 * command immediately, instead of going into an infinite
574 * (or even just a very long) retry loop.
575 */
576 if (++us->last_sector_retries < 3)
577 return;
578 srb->result = SAM_STAT_CHECK_CONDITION;
579 memcpy(srb->sense_buffer, record_not_found,
580 sizeof(record_not_found));
581 }
582
583 done:
584 /* Don't reset the retry counter for TEST UNIT READY commands,
585 * because they get issued after device resets which might be
586 * caused by a failed last-sector access.
587 */
588 if (srb->cmnd[0] != TEST_UNIT_READY)
589 us->last_sector_retries = 0;
590}
591
592/* Invoke the transport and basic error-handling/recovery methods
593 *
594 * This is used by the protocol layers to actually send the message to
595 * the device and receive the response.
596 */
597void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
598{
599 int need_auto_sense;
600 int result;
601
602 /* send the command to the transport layer */
603 scsi_set_resid(srb, 0);
604 result = us->transport(srb, us);
605
606 /* if the command gets aborted by the higher layers, we need to
607 * short-circuit all other processing
608 */
609 if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
610 usb_stor_dbg(us, "-- command was aborted\n");
611 srb->result = DID_ABORT << 16;
612 goto Handle_Errors;
613 }
614
615 /* if there is a transport error, reset and don't auto-sense */
616 if (result == USB_STOR_TRANSPORT_ERROR) {
617 usb_stor_dbg(us, "-- transport indicates error, resetting\n");
618 srb->result = DID_ERROR << 16;
619 goto Handle_Errors;
620 }
621
622 /* if the transport provided its own sense data, don't auto-sense */
623 if (result == USB_STOR_TRANSPORT_NO_SENSE) {
624 srb->result = SAM_STAT_CHECK_CONDITION;
625 last_sector_hacks(us, srb);
626 return;
627 }
628
629 srb->result = SAM_STAT_GOOD;
630
631 /* Determine if we need to auto-sense
632 *
633 * I normally don't use a flag like this, but it's almost impossible
634 * to understand what's going on here if I don't.
635 */
636 need_auto_sense = 0;
637
638 /*
639 * If we're running the CB transport, which is incapable
640 * of determining status on its own, we will auto-sense
641 * unless the operation involved a data-in transfer. Devices
642 * can signal most data-in errors by stalling the bulk-in pipe.
643 */
644 if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_DPCM_USB) &&
645 srb->sc_data_direction != DMA_FROM_DEVICE) {
646 usb_stor_dbg(us, "-- CB transport device requiring auto-sense\n");
647 need_auto_sense = 1;
648 }
649
650 /*
651 * If we have a failure, we're going to do a REQUEST_SENSE
652 * automatically. Note that we differentiate between a command
653 * "failure" and an "error" in the transport mechanism.
654 */
655 if (result == USB_STOR_TRANSPORT_FAILED) {
656 usb_stor_dbg(us, "-- transport indicates command failure\n");
657 need_auto_sense = 1;
658 }
659
660 /*
661 * Determine if this device is SAT by seeing if the
662 * command executed successfully. Otherwise we'll have
663 * to wait for at least one CHECK_CONDITION to determine
664 * SANE_SENSE support
665 */
666 if (unlikely((srb->cmnd[0] == ATA_16 || srb->cmnd[0] == ATA_12) &&
667 result == USB_STOR_TRANSPORT_GOOD &&
668 !(us->fflags & US_FL_SANE_SENSE) &&
669 !(us->fflags & US_FL_BAD_SENSE) &&
670 !(srb->cmnd[2] & 0x20))) {
671 usb_stor_dbg(us, "-- SAT supported, increasing auto-sense\n");
672 us->fflags |= US_FL_SANE_SENSE;
673 }
674
675 /*
676 * A short transfer on a command where we don't expect it
677 * is unusual, but it doesn't mean we need to auto-sense.
678 */
679 if ((scsi_get_resid(srb) > 0) &&
680 !((srb->cmnd[0] == REQUEST_SENSE) ||
681 (srb->cmnd[0] == INQUIRY) ||
682 (srb->cmnd[0] == MODE_SENSE) ||
683 (srb->cmnd[0] == LOG_SENSE) ||
684 (srb->cmnd[0] == MODE_SENSE_10))) {
685 usb_stor_dbg(us, "-- unexpectedly short transfer\n");
686 }
687
688 /* Now, if we need to do the auto-sense, let's do it */
689 if (need_auto_sense) {
690 int temp_result;
691 struct scsi_eh_save ses;
692 int sense_size = US_SENSE_SIZE;
693 struct scsi_sense_hdr sshdr;
694 const u8 *scdd;
695 u8 fm_ili;
696
697 /* device supports and needs bigger sense buffer */
698 if (us->fflags & US_FL_SANE_SENSE)
699 sense_size = ~0;
700Retry_Sense:
701 usb_stor_dbg(us, "Issuing auto-REQUEST_SENSE\n");
702
703 scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sense_size);
704
705 /* FIXME: we must do the protocol translation here */
706 if (us->subclass == USB_SC_RBC || us->subclass == USB_SC_SCSI ||
707 us->subclass == USB_SC_CYP_ATACB)
708 srb->cmd_len = 6;
709 else
710 srb->cmd_len = 12;
711
712 /* issue the auto-sense command */
713 scsi_set_resid(srb, 0);
714 temp_result = us->transport(us->srb, us);
715
716 /* let's clean up right away */
717 scsi_eh_restore_cmnd(srb, &ses);
718
719 if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
720 usb_stor_dbg(us, "-- auto-sense aborted\n");
721 srb->result = DID_ABORT << 16;
722
723 /* If SANE_SENSE caused this problem, disable it */
724 if (sense_size != US_SENSE_SIZE) {
725 us->fflags &= ~US_FL_SANE_SENSE;
726 us->fflags |= US_FL_BAD_SENSE;
727 }
728 goto Handle_Errors;
729 }
730
731 /* Some devices claim to support larger sense but fail when
732 * trying to request it. When a transport failure happens
733 * using US_FS_SANE_SENSE, we always retry with a standard
734 * (small) sense request. This fixes some USB GSM modems
735 */
736 if (temp_result == USB_STOR_TRANSPORT_FAILED &&
737 sense_size != US_SENSE_SIZE) {
738 usb_stor_dbg(us, "-- auto-sense failure, retry small sense\n");
739 sense_size = US_SENSE_SIZE;
740 us->fflags &= ~US_FL_SANE_SENSE;
741 us->fflags |= US_FL_BAD_SENSE;
742 goto Retry_Sense;
743 }
744
745 /* Other failures */
746 if (temp_result != USB_STOR_TRANSPORT_GOOD) {
747 usb_stor_dbg(us, "-- auto-sense failure\n");
748
749 /* we skip the reset if this happens to be a
750 * multi-target device, since failure of an
751 * auto-sense is perfectly valid
752 */
753 srb->result = DID_ERROR << 16;
754 if (!(us->fflags & US_FL_SCM_MULT_TARG))
755 goto Handle_Errors;
756 return;
757 }
758
759 /* If the sense data returned is larger than 18-bytes then we
760 * assume this device supports requesting more in the future.
761 * The response code must be 70h through 73h inclusive.
762 */
763 if (srb->sense_buffer[7] > (US_SENSE_SIZE - 8) &&
764 !(us->fflags & US_FL_SANE_SENSE) &&
765 !(us->fflags & US_FL_BAD_SENSE) &&
766 (srb->sense_buffer[0] & 0x7C) == 0x70) {
767 usb_stor_dbg(us, "-- SANE_SENSE support enabled\n");
768 us->fflags |= US_FL_SANE_SENSE;
769
770 /* Indicate to the user that we truncated their sense
771 * because we didn't know it supported larger sense.
772 */
773 usb_stor_dbg(us, "-- Sense data truncated to %i from %i\n",
774 US_SENSE_SIZE,
775 srb->sense_buffer[7] + 8);
776 srb->sense_buffer[7] = (US_SENSE_SIZE - 8);
777 }
778
779 scsi_normalize_sense(srb->sense_buffer, SCSI_SENSE_BUFFERSIZE,
780 &sshdr);
781
782 usb_stor_dbg(us, "-- Result from auto-sense is %d\n",
783 temp_result);
784 usb_stor_dbg(us, "-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n",
785 sshdr.response_code, sshdr.sense_key,
786 sshdr.asc, sshdr.ascq);
787#ifdef CONFIG_USB_STORAGE_DEBUG
788 usb_stor_show_sense(us, sshdr.sense_key, sshdr.asc, sshdr.ascq);
789#endif
790
791 /* set the result so the higher layers expect this data */
792 srb->result = SAM_STAT_CHECK_CONDITION;
793
794 scdd = scsi_sense_desc_find(srb->sense_buffer,
795 SCSI_SENSE_BUFFERSIZE, 4);
796 fm_ili = (scdd ? scdd[3] : srb->sense_buffer[2]) & 0xA0;
797
798 /* We often get empty sense data. This could indicate that
799 * everything worked or that there was an unspecified
800 * problem. We have to decide which.
801 */
802 if (sshdr.sense_key == 0 && sshdr.asc == 0 && sshdr.ascq == 0 &&
803 fm_ili == 0) {
804 /* If things are really okay, then let's show that.
805 * Zero out the sense buffer so the higher layers
806 * won't realize we did an unsolicited auto-sense.
807 */
808 if (result == USB_STOR_TRANSPORT_GOOD) {
809 srb->result = SAM_STAT_GOOD;
810 srb->sense_buffer[0] = 0x0;
811
812 /* If there was a problem, report an unspecified
813 * hardware error to prevent the higher layers from
814 * entering an infinite retry loop.
815 */
816 } else {
817 srb->result = DID_ERROR << 16;
818 if ((sshdr.response_code & 0x72) == 0x72)
819 srb->sense_buffer[1] = HARDWARE_ERROR;
820 else
821 srb->sense_buffer[2] = HARDWARE_ERROR;
822 }
823 }
824 }
825
826 /*
827 * Some devices don't work or return incorrect data the first
828 * time they get a READ(10) command, or for the first READ(10)
829 * after a media change. If the INITIAL_READ10 flag is set,
830 * keep track of whether READ(10) commands succeed. If the
831 * previous one succeeded and this one failed, set the REDO_READ10
832 * flag to force a retry.
833 */
834 if (unlikely((us->fflags & US_FL_INITIAL_READ10) &&
835 srb->cmnd[0] == READ_10)) {
836 if (srb->result == SAM_STAT_GOOD) {
837 set_bit(US_FLIDX_READ10_WORKED, &us->dflags);
838 } else if (test_bit(US_FLIDX_READ10_WORKED, &us->dflags)) {
839 clear_bit(US_FLIDX_READ10_WORKED, &us->dflags);
840 set_bit(US_FLIDX_REDO_READ10, &us->dflags);
841 }
842
843 /*
844 * Next, if the REDO_READ10 flag is set, return a result
845 * code that will cause the SCSI core to retry the READ(10)
846 * command immediately.
847 */
848 if (test_bit(US_FLIDX_REDO_READ10, &us->dflags)) {
849 clear_bit(US_FLIDX_REDO_READ10, &us->dflags);
850 srb->result = DID_IMM_RETRY << 16;
851 srb->sense_buffer[0] = 0;
852 }
853 }
854
855 /* Did we transfer less than the minimum amount required? */
856 if ((srb->result == SAM_STAT_GOOD || srb->sense_buffer[2] == 0) &&
857 scsi_bufflen(srb) - scsi_get_resid(srb) < srb->underflow)
858 srb->result = DID_ERROR << 16;
859
860 last_sector_hacks(us, srb);
861 return;
862
863 /* Error and abort processing: try to resynchronize with the device
864 * by issuing a port reset. If that fails, try a class-specific
865 * device reset. */
866 Handle_Errors:
867
868 /* Set the RESETTING bit, and clear the ABORTING bit so that
869 * the reset may proceed. */
870 scsi_lock(us_to_host(us));
871 set_bit(US_FLIDX_RESETTING, &us->dflags);
872 clear_bit(US_FLIDX_ABORTING, &us->dflags);
873 scsi_unlock(us_to_host(us));
874
875 /* We must release the device lock because the pre_reset routine
876 * will want to acquire it. */
877 mutex_unlock(&us->dev_mutex);
878 result = usb_stor_port_reset(us);
879 mutex_lock(&us->dev_mutex);
880
881 if (result < 0) {
882 scsi_lock(us_to_host(us));
883 usb_stor_report_device_reset(us);
884 scsi_unlock(us_to_host(us));
885 us->transport_reset(us);
886 }
887 clear_bit(US_FLIDX_RESETTING, &us->dflags);
888 last_sector_hacks(us, srb);
889}
890
891/* Stop the current URB transfer */
892void usb_stor_stop_transport(struct us_data *us)
893{
894 /* If the state machine is blocked waiting for an URB,
895 * let's wake it up. The test_and_clear_bit() call
896 * guarantees that if a URB has just been submitted,
897 * it won't be cancelled more than once. */
898 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
899 usb_stor_dbg(us, "-- cancelling URB\n");
900 usb_unlink_urb(us->current_urb);
901 }
902
903 /* If we are waiting for a scatter-gather operation, cancel it. */
904 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
905 usb_stor_dbg(us, "-- cancelling sg request\n");
906 usb_sg_cancel(&us->current_sg);
907 }
908}
909
910/*
911 * Control/Bulk and Control/Bulk/Interrupt transport
912 */
913
914int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us)
915{
916 unsigned int transfer_length = scsi_bufflen(srb);
917 unsigned int pipe = 0;
918 int result;
919
920 /* COMMAND STAGE */
921 /* let's send the command via the control pipe */
922 result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe,
923 US_CBI_ADSC,
924 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0,
925 us->ifnum, srb->cmnd, srb->cmd_len);
926
927 /* check the return code for the command */
928 usb_stor_dbg(us, "Call to usb_stor_ctrl_transfer() returned %d\n",
929 result);
930
931 /* if we stalled the command, it means command failed */
932 if (result == USB_STOR_XFER_STALLED) {
933 return USB_STOR_TRANSPORT_FAILED;
934 }
935
936 /* Uh oh... serious problem here */
937 if (result != USB_STOR_XFER_GOOD) {
938 return USB_STOR_TRANSPORT_ERROR;
939 }
940
941 /* DATA STAGE */
942 /* transfer the data payload for this command, if one exists*/
943 if (transfer_length) {
944 pipe = srb->sc_data_direction == DMA_FROM_DEVICE ?
945 us->recv_bulk_pipe : us->send_bulk_pipe;
946 result = usb_stor_bulk_srb(us, pipe, srb);
947 usb_stor_dbg(us, "CBI data stage result is 0x%x\n", result);
948
949 /* if we stalled the data transfer it means command failed */
950 if (result == USB_STOR_XFER_STALLED)
951 return USB_STOR_TRANSPORT_FAILED;
952 if (result > USB_STOR_XFER_STALLED)
953 return USB_STOR_TRANSPORT_ERROR;
954 }
955
956 /* STATUS STAGE */
957
958 /* NOTE: CB does not have a status stage. Silly, I know. So
959 * we have to catch this at a higher level.
960 */
961 if (us->protocol != USB_PR_CBI)
962 return USB_STOR_TRANSPORT_GOOD;
963
964 result = usb_stor_intr_transfer(us, us->iobuf, 2);
965 usb_stor_dbg(us, "Got interrupt data (0x%x, 0x%x)\n",
966 us->iobuf[0], us->iobuf[1]);
967 if (result != USB_STOR_XFER_GOOD)
968 return USB_STOR_TRANSPORT_ERROR;
969
970 /* UFI gives us ASC and ASCQ, like a request sense
971 *
972 * REQUEST_SENSE and INQUIRY don't affect the sense data on UFI
973 * devices, so we ignore the information for those commands. Note
974 * that this means we could be ignoring a real error on these
975 * commands, but that can't be helped.
976 */
977 if (us->subclass == USB_SC_UFI) {
978 if (srb->cmnd[0] == REQUEST_SENSE ||
979 srb->cmnd[0] == INQUIRY)
980 return USB_STOR_TRANSPORT_GOOD;
981 if (us->iobuf[0])
982 goto Failed;
983 return USB_STOR_TRANSPORT_GOOD;
984 }
985
986 /* If not UFI, we interpret the data as a result code
987 * The first byte should always be a 0x0.
988 *
989 * Some bogus devices don't follow that rule. They stuff the ASC
990 * into the first byte -- so if it's non-zero, call it a failure.
991 */
992 if (us->iobuf[0]) {
993 usb_stor_dbg(us, "CBI IRQ data showed reserved bType 0x%x\n",
994 us->iobuf[0]);
995 goto Failed;
996
997 }
998
999 /* The second byte & 0x0F should be 0x0 for good, otherwise error */
1000 switch (us->iobuf[1] & 0x0F) {
1001 case 0x00:
1002 return USB_STOR_TRANSPORT_GOOD;
1003 case 0x01:
1004 goto Failed;
1005 }
1006 return USB_STOR_TRANSPORT_ERROR;
1007
1008 /* the CBI spec requires that the bulk pipe must be cleared
1009 * following any data-in/out command failure (section 2.4.3.1.3)
1010 */
1011 Failed:
1012 if (pipe)
1013 usb_stor_clear_halt(us, pipe);
1014 return USB_STOR_TRANSPORT_FAILED;
1015}
1016EXPORT_SYMBOL_GPL(usb_stor_CB_transport);
1017
1018/*
1019 * Bulk only transport
1020 */
1021
1022/* Determine what the maximum LUN supported is */
1023int usb_stor_Bulk_max_lun(struct us_data *us)
1024{
1025 int result;
1026
1027 /* issue the command */
1028 us->iobuf[0] = 0;
1029 result = usb_stor_control_msg(us, us->recv_ctrl_pipe,
1030 US_BULK_GET_MAX_LUN,
1031 USB_DIR_IN | USB_TYPE_CLASS |
1032 USB_RECIP_INTERFACE,
1033 0, us->ifnum, us->iobuf, 1, 10*HZ);
1034
1035 usb_stor_dbg(us, "GetMaxLUN command result is %d, data is %d\n",
1036 result, us->iobuf[0]);
1037
1038 /*
1039 * If we have a successful request, return the result if valid. The
1040 * CBW LUN field is 4 bits wide, so the value reported by the device
1041 * should fit into that.
1042 */
1043 if (result > 0) {
1044 if (us->iobuf[0] < 16) {
1045 return us->iobuf[0];
1046 } else {
1047 dev_info(&us->pusb_intf->dev,
1048 "Max LUN %d is not valid, using 0 instead",
1049 us->iobuf[0]);
1050 }
1051 }
1052
1053 /*
1054 * Some devices don't like GetMaxLUN. They may STALL the control
1055 * pipe, they may return a zero-length result, they may do nothing at
1056 * all and timeout, or they may fail in even more bizarrely creative
1057 * ways. In these cases the best approach is to use the default
1058 * value: only one LUN.
1059 */
1060 return 0;
1061}
1062
1063int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
1064{
1065 struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf;
1066 struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf;
1067 unsigned int transfer_length = scsi_bufflen(srb);
1068 unsigned int residue;
1069 int result;
1070 int fake_sense = 0;
1071 unsigned int cswlen;
1072 unsigned int cbwlen = US_BULK_CB_WRAP_LEN;
1073
1074 /* Take care of BULK32 devices; set extra byte to 0 */
1075 if (unlikely(us->fflags & US_FL_BULK32)) {
1076 cbwlen = 32;
1077 us->iobuf[31] = 0;
1078 }
1079
1080 /* set up the command wrapper */
1081 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
1082 bcb->DataTransferLength = cpu_to_le32(transfer_length);
1083 bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ?
1084 US_BULK_FLAG_IN : 0;
1085 bcb->Tag = ++us->tag;
1086 bcb->Lun = srb->device->lun;
1087 if (us->fflags & US_FL_SCM_MULT_TARG)
1088 bcb->Lun |= srb->device->id << 4;
1089 bcb->Length = srb->cmd_len;
1090
1091 /* copy the command payload */
1092 memset(bcb->CDB, 0, sizeof(bcb->CDB));
1093 memcpy(bcb->CDB, srb->cmnd, bcb->Length);
1094
1095 /* send it to out endpoint */
1096 usb_stor_dbg(us, "Bulk Command S 0x%x T 0x%x L %d F %d Trg %d LUN %d CL %d\n",
1097 le32_to_cpu(bcb->Signature), bcb->Tag,
1098 le32_to_cpu(bcb->DataTransferLength), bcb->Flags,
1099 (bcb->Lun >> 4), (bcb->Lun & 0x0F),
1100 bcb->Length);
1101 result = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
1102 bcb, cbwlen, NULL);
1103 usb_stor_dbg(us, "Bulk command transfer result=%d\n", result);
1104 if (result != USB_STOR_XFER_GOOD)
1105 return USB_STOR_TRANSPORT_ERROR;
1106
1107 /* DATA STAGE */
1108 /* send/receive data payload, if there is any */
1109
1110 /* Some USB-IDE converter chips need a 100us delay between the
1111 * command phase and the data phase. Some devices need a little
1112 * more than that, probably because of clock rate inaccuracies. */
1113 if (unlikely(us->fflags & US_FL_GO_SLOW))
1114 usleep_range(125, 150);
1115
1116 if (transfer_length) {
1117 unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ?
1118 us->recv_bulk_pipe : us->send_bulk_pipe;
1119 result = usb_stor_bulk_srb(us, pipe, srb);
1120 usb_stor_dbg(us, "Bulk data transfer result 0x%x\n", result);
1121 if (result == USB_STOR_XFER_ERROR)
1122 return USB_STOR_TRANSPORT_ERROR;
1123
1124 /* If the device tried to send back more data than the
1125 * amount requested, the spec requires us to transfer
1126 * the CSW anyway. Since there's no point retrying the
1127 * the command, we'll return fake sense data indicating
1128 * Illegal Request, Invalid Field in CDB.
1129 */
1130 if (result == USB_STOR_XFER_LONG)
1131 fake_sense = 1;
1132
1133 /*
1134 * Sometimes a device will mistakenly skip the data phase
1135 * and go directly to the status phase without sending a
1136 * zero-length packet. If we get a 13-byte response here,
1137 * check whether it really is a CSW.
1138 */
1139 if (result == USB_STOR_XFER_SHORT &&
1140 srb->sc_data_direction == DMA_FROM_DEVICE &&
1141 transfer_length - scsi_get_resid(srb) ==
1142 US_BULK_CS_WRAP_LEN) {
1143 struct scatterlist *sg = NULL;
1144 unsigned int offset = 0;
1145
1146 if (usb_stor_access_xfer_buf((unsigned char *) bcs,
1147 US_BULK_CS_WRAP_LEN, srb, &sg,
1148 &offset, FROM_XFER_BUF) ==
1149 US_BULK_CS_WRAP_LEN &&
1150 bcs->Signature ==
1151 cpu_to_le32(US_BULK_CS_SIGN)) {
1152 usb_stor_dbg(us, "Device skipped data phase\n");
1153 scsi_set_resid(srb, transfer_length);
1154 goto skipped_data_phase;
1155 }
1156 }
1157 }
1158
1159 /* See flow chart on pg 15 of the Bulk Only Transport spec for
1160 * an explanation of how this code works.
1161 */
1162
1163 /* get CSW for device status */
1164 usb_stor_dbg(us, "Attempting to get CSW...\n");
1165 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1166 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
1167
1168 /* Some broken devices add unnecessary zero-length packets to the
1169 * end of their data transfers. Such packets show up as 0-length
1170 * CSWs. If we encounter such a thing, try to read the CSW again.
1171 */
1172 if (result == USB_STOR_XFER_SHORT && cswlen == 0) {
1173 usb_stor_dbg(us, "Received 0-length CSW; retrying...\n");
1174 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1175 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
1176 }
1177
1178 /* did the attempt to read the CSW fail? */
1179 if (result == USB_STOR_XFER_STALLED) {
1180
1181 /* get the status again */
1182 usb_stor_dbg(us, "Attempting to get CSW (2nd try)...\n");
1183 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
1184 bcs, US_BULK_CS_WRAP_LEN, NULL);
1185 }
1186
1187 /* if we still have a failure at this point, we're in trouble */
1188 usb_stor_dbg(us, "Bulk status result = %d\n", result);
1189 if (result != USB_STOR_XFER_GOOD)
1190 return USB_STOR_TRANSPORT_ERROR;
1191
1192 skipped_data_phase:
1193 /* check bulk status */
1194 residue = le32_to_cpu(bcs->Residue);
1195 usb_stor_dbg(us, "Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n",
1196 le32_to_cpu(bcs->Signature), bcs->Tag,
1197 residue, bcs->Status);
1198 if (!(bcs->Tag == us->tag || (us->fflags & US_FL_BULK_IGNORE_TAG)) ||
1199 bcs->Status > US_BULK_STAT_PHASE) {
1200 usb_stor_dbg(us, "Bulk logical error\n");
1201 return USB_STOR_TRANSPORT_ERROR;
1202 }
1203
1204 /* Some broken devices report odd signatures, so we do not check them
1205 * for validity against the spec. We store the first one we see,
1206 * and check subsequent transfers for validity against this signature.
1207 */
1208 if (!us->bcs_signature) {
1209 us->bcs_signature = bcs->Signature;
1210 if (us->bcs_signature != cpu_to_le32(US_BULK_CS_SIGN))
1211 usb_stor_dbg(us, "Learnt BCS signature 0x%08X\n",
1212 le32_to_cpu(us->bcs_signature));
1213 } else if (bcs->Signature != us->bcs_signature) {
1214 usb_stor_dbg(us, "Signature mismatch: got %08X, expecting %08X\n",
1215 le32_to_cpu(bcs->Signature),
1216 le32_to_cpu(us->bcs_signature));
1217 return USB_STOR_TRANSPORT_ERROR;
1218 }
1219
1220 /* try to compute the actual residue, based on how much data
1221 * was really transferred and what the device tells us */
1222 if (residue && !(us->fflags & US_FL_IGNORE_RESIDUE)) {
1223
1224 /* Heuristically detect devices that generate bogus residues
1225 * by seeing what happens with INQUIRY and READ CAPACITY
1226 * commands.
1227 */
1228 if (bcs->Status == US_BULK_STAT_OK &&
1229 scsi_get_resid(srb) == 0 &&
1230 ((srb->cmnd[0] == INQUIRY &&
1231 transfer_length == 36) ||
1232 (srb->cmnd[0] == READ_CAPACITY &&
1233 transfer_length == 8))) {
1234 us->fflags |= US_FL_IGNORE_RESIDUE;
1235
1236 } else {
1237 residue = min(residue, transfer_length);
1238 scsi_set_resid(srb, max(scsi_get_resid(srb),
1239 (int) residue));
1240 }
1241 }
1242
1243 /* based on the status code, we report good or bad */
1244 switch (bcs->Status) {
1245 case US_BULK_STAT_OK:
1246 /* device babbled -- return fake sense data */
1247 if (fake_sense) {
1248 memcpy(srb->sense_buffer,
1249 usb_stor_sense_invalidCDB,
1250 sizeof(usb_stor_sense_invalidCDB));
1251 return USB_STOR_TRANSPORT_NO_SENSE;
1252 }
1253
1254 /* command good -- note that data could be short */
1255 return USB_STOR_TRANSPORT_GOOD;
1256
1257 case US_BULK_STAT_FAIL:
1258 /* command failed */
1259 return USB_STOR_TRANSPORT_FAILED;
1260
1261 case US_BULK_STAT_PHASE:
1262 /* phase error -- note that a transport reset will be
1263 * invoked by the invoke_transport() function
1264 */
1265 return USB_STOR_TRANSPORT_ERROR;
1266 }
1267
1268 /* we should never get here, but if we do, we're in trouble */
1269 return USB_STOR_TRANSPORT_ERROR;
1270}
1271EXPORT_SYMBOL_GPL(usb_stor_Bulk_transport);
1272
1273/***********************************************************************
1274 * Reset routines
1275 ***********************************************************************/
1276
1277/* This is the common part of the device reset code.
1278 *
1279 * It's handy that every transport mechanism uses the control endpoint for
1280 * resets.
1281 *
1282 * Basically, we send a reset with a 5-second timeout, so we don't get
1283 * jammed attempting to do the reset.
1284 */
1285static int usb_stor_reset_common(struct us_data *us,
1286 u8 request, u8 requesttype,
1287 u16 value, u16 index, void *data, u16 size)
1288{
1289 int result;
1290 int result2;
1291
1292 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
1293 usb_stor_dbg(us, "No reset during disconnect\n");
1294 return -EIO;
1295 }
1296
1297 result = usb_stor_control_msg(us, us->send_ctrl_pipe,
1298 request, requesttype, value, index, data, size,
1299 5*HZ);
1300 if (result < 0) {
1301 usb_stor_dbg(us, "Soft reset failed: %d\n", result);
1302 return result;
1303 }
1304
1305 /* Give the device some time to recover from the reset,
1306 * but don't delay disconnect processing. */
1307 wait_event_interruptible_timeout(us->delay_wait,
1308 test_bit(US_FLIDX_DISCONNECTING, &us->dflags),
1309 HZ*6);
1310 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
1311 usb_stor_dbg(us, "Reset interrupted by disconnect\n");
1312 return -EIO;
1313 }
1314
1315 usb_stor_dbg(us, "Soft reset: clearing bulk-in endpoint halt\n");
1316 result = usb_stor_clear_halt(us, us->recv_bulk_pipe);
1317
1318 usb_stor_dbg(us, "Soft reset: clearing bulk-out endpoint halt\n");
1319 result2 = usb_stor_clear_halt(us, us->send_bulk_pipe);
1320
1321 /* return a result code based on the result of the clear-halts */
1322 if (result >= 0)
1323 result = result2;
1324 if (result < 0)
1325 usb_stor_dbg(us, "Soft reset failed\n");
1326 else
1327 usb_stor_dbg(us, "Soft reset done\n");
1328 return result;
1329}
1330
1331/* This issues a CB[I] Reset to the device in question
1332 */
1333#define CB_RESET_CMD_SIZE 12
1334
1335int usb_stor_CB_reset(struct us_data *us)
1336{
1337 memset(us->iobuf, 0xFF, CB_RESET_CMD_SIZE);
1338 us->iobuf[0] = SEND_DIAGNOSTIC;
1339 us->iobuf[1] = 4;
1340 return usb_stor_reset_common(us, US_CBI_ADSC,
1341 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1342 0, us->ifnum, us->iobuf, CB_RESET_CMD_SIZE);
1343}
1344EXPORT_SYMBOL_GPL(usb_stor_CB_reset);
1345
1346/* This issues a Bulk-only Reset to the device in question, including
1347 * clearing the subsequent endpoint halts that may occur.
1348 */
1349int usb_stor_Bulk_reset(struct us_data *us)
1350{
1351 return usb_stor_reset_common(us, US_BULK_RESET_REQUEST,
1352 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1353 0, us->ifnum, NULL, 0);
1354}
1355EXPORT_SYMBOL_GPL(usb_stor_Bulk_reset);
1356
1357/* Issue a USB port reset to the device. The caller must not hold
1358 * us->dev_mutex.
1359 */
1360int usb_stor_port_reset(struct us_data *us)
1361{
1362 int result;
1363
1364 /*for these devices we must use the class specific method */
1365 if (us->pusb_dev->quirks & USB_QUIRK_RESET)
1366 return -EPERM;
1367
1368 result = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
1369 if (result < 0)
1370 usb_stor_dbg(us, "unable to lock device for reset: %d\n",
1371 result);
1372 else {
1373 /* Were we disconnected while waiting for the lock? */
1374 if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
1375 result = -EIO;
1376 usb_stor_dbg(us, "No reset during disconnect\n");
1377 } else {
1378 result = usb_reset_device(us->pusb_dev);
1379 usb_stor_dbg(us, "usb_reset_device returns %d\n",
1380 result);
1381 }
1382 usb_unlock_device(us->pusb_dev);
1383 }
1384 return result;
1385}