1 /* Driver for USB Mass Storage compliant devices 2 * 3 * $Id: transport.c,v 1.47 2002/04/22 03:39:43 mdharm Exp $ 4 * 5 * Current development and maintenance by: 6 * (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net) 7 * 8 * Developed with the assistance of: 9 * (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org) 10 * (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov) 11 * (c) 2002 Alan Stern <stern@rowland.org> 12 * 13 * Initial work by: 14 * (c) 1999 Michael Gee (michael@linuxspecific.com) 15 * 16 * This driver is based on the 'USB Mass Storage Class' document. This 17 * describes in detail the protocol used to communicate with such 18 * devices. Clearly, the designers had SCSI and ATAPI commands in 19 * mind when they created this document. The commands are all very 20 * similar to commands in the SCSI-II and ATAPI specifications. 21 * 22 * It is important to note that in a number of cases this class 23 * exhibits class-specific exemptions from the USB specification. 24 * Notably the usage of NAK, STALL and ACK differs from the norm, in 25 * that they are used to communicate wait, failed and OK on commands. 26 * 27 * Also, for certain devices, the interrupt endpoint is used to convey 28 * status of a command. 29 * 30 * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more 31 * information about this driver. 32 * 33 * This program is free software; you can redistribute it and/or modify it 34 * under the terms of the GNU General Public License as published by the 35 * Free Software Foundation; either version 2, or (at your option) any 36 * later version. 37 * 38 * This program is distributed in the hope that it will be useful, but 39 * WITHOUT ANY WARRANTY; without even the implied warranty of 40 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 41 * General Public License for more details. 42 * 43 * You should have received a copy of the GNU General Public License along 44 * with this program; if not, write to the Free Software Foundation, Inc., 45 * 675 Mass Ave, Cambridge, MA 02139, USA. 46 */ 47 48 #include <linux/sched.h> 49 #include <linux/errno.h> 50 #include <linux/slab.h> 51 52 #include <scsi/scsi.h> 53 #include <scsi/scsi_cmnd.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 63 /*********************************************************************** 64 * Data transfer routines 65 ***********************************************************************/ 66 67 /* 68 * This is subtle, so pay attention: 69 * --------------------------------- 70 * We're very concerned about races with a command abort. Hanging this code 71 * is a sure fire way to hang the kernel. (Note that this discussion applies 72 * only to transactions resulting from a scsi queued-command, since only 73 * these transactions are subject to a scsi abort. Other transactions, such 74 * as those occurring during device-specific initialization, must be handled 75 * by a separate code path.) 76 * 77 * The abort function (usb_storage_command_abort() in scsiglue.c) first 78 * sets the machine state and the ABORTING bit in us->flags to prevent 79 * new URBs from being submitted. It then calls usb_stor_stop_transport() 80 * below, which atomically tests-and-clears the URB_ACTIVE bit in us->flags 81 * to see if the current_urb needs to be stopped. Likewise, the SG_ACTIVE 82 * bit is tested to see if the current_sg scatter-gather request needs to be 83 * stopped. The timeout callback routine does much the same thing. 84 * 85 * When a disconnect occurs, the DISCONNECTING bit in us->flags is set to 86 * prevent new URBs from being submitted, and usb_stor_stop_transport() is 87 * called to stop any ongoing requests. 88 * 89 * The submit function first verifies that the submitting is allowed 90 * (neither ABORTING nor DISCONNECTING bits are set) and that the submit 91 * completes without errors, and only then sets the URB_ACTIVE bit. This 92 * prevents the stop_transport() function from trying to cancel the URB 93 * while the submit call is underway. Next, the submit function must test 94 * the flags to see if an abort or disconnect occurred during the submission 95 * or before the URB_ACTIVE bit was set. If so, it's essential to cancel 96 * the URB if it hasn't been cancelled already (i.e., if the URB_ACTIVE bit 97 * is still set). Either way, the function must then wait for the URB to 98 * finish. Note that the URB can still be in progress even after a call to 99 * usb_unlink_urb() returns. 100 * 101 * The idea is that (1) once the ABORTING or DISCONNECTING bit is set, 102 * either the stop_transport() function or the submitting function 103 * is guaranteed to call usb_unlink_urb() for an active URB, 104 * and (2) test_and_clear_bit() prevents usb_unlink_urb() from being 105 * called more than once or from being called during usb_submit_urb(). 106 */ 107 108 /* This is the completion handler which will wake us up when an URB 109 * completes. 110 */ 111 static void usb_stor_blocking_completion(struct urb *urb, struct pt_regs *regs) 112 { 113 struct completion *urb_done_ptr = (struct completion *)urb->context; 114 115 complete(urb_done_ptr); 116 } 117 118 /* This is the common part of the URB message submission code 119 * 120 * All URBs from the usb-storage driver involved in handling a queued scsi 121 * command _must_ pass through this function (or something like it) for the 122 * abort mechanisms to work properly. 123 */ 124 static int usb_stor_msg_common(struct us_data *us, int timeout) 125 { 126 struct completion urb_done; 127 long timeleft; 128 int status; 129 130 /* don't submit URBs during abort/disconnect processing */ 131 if (us->flags & ABORTING_OR_DISCONNECTING) 132 return -EIO; 133 134 /* set up data structures for the wakeup system */ 135 init_completion(&urb_done); 136 137 /* fill the common fields in the URB */ 138 us->current_urb->context = &urb_done; 139 us->current_urb->actual_length = 0; 140 us->current_urb->error_count = 0; 141 us->current_urb->status = 0; 142 143 /* we assume that if transfer_buffer isn't us->iobuf then it 144 * hasn't been mapped for DMA. Yes, this is clunky, but it's 145 * easier than always having the caller tell us whether the 146 * transfer buffer has already been mapped. */ 147 us->current_urb->transfer_flags = URB_NO_SETUP_DMA_MAP; 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 us->current_urb->setup_dma = us->cr_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->flags); 163 164 /* did an abort/disconnect occur during the submission? */ 165 if (us->flags & ABORTING_OR_DISCONNECTING) { 166 167 /* cancel the URB, if it hasn't been cancelled already */ 168 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) { 169 US_DEBUGP("-- 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->flags); 179 180 if (timeleft <= 0) { 181 US_DEBUGP("%s -- cancelling URB\n", 182 timeleft == 0 ? "Timeout" : "Signal"); 183 usb_unlink_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 */ 194 int 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 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n", 201 __FUNCTION__, request, requesttype, 202 value, index, size); 203 204 /* fill in the devrequest structure */ 205 us->cr->bRequestType = requesttype; 206 us->cr->bRequest = request; 207 us->cr->wValue = cpu_to_le16(value); 208 us->cr->wIndex = cpu_to_le16(index); 209 us->cr->wLength = cpu_to_le16(size); 210 211 /* fill and submit the URB */ 212 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe, 213 (unsigned char*) us->cr, data, size, 214 usb_stor_blocking_completion, NULL); 215 status = usb_stor_msg_common(us, timeout); 216 217 /* return the actual length of the data transferred if no error */ 218 if (status == 0) 219 status = us->current_urb->actual_length; 220 return status; 221 } 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 */ 235 int 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 /* reset the endpoint toggle */ 249 if (result >= 0) 250 usb_settoggle(us->pusb_dev, usb_pipeendpoint(pipe), 251 usb_pipeout(pipe), 0); 252 253 US_DEBUGP("%s: result = %d\n", __FUNCTION__, result); 254 return result; 255 } 256 257 258 /* 259 * Interpret the results of a URB transfer 260 * 261 * This function prints appropriate debugging messages, clears halts on 262 * non-control endpoints, and translates the status to the corresponding 263 * USB_STOR_XFER_xxx return code. 264 */ 265 static int interpret_urb_result(struct us_data *us, unsigned int pipe, 266 unsigned int length, int result, unsigned int partial) 267 { 268 US_DEBUGP("Status code %d; transferred %u/%u\n", 269 result, partial, length); 270 switch (result) { 271 272 /* no error code; did we send all the data? */ 273 case 0: 274 if (partial != length) { 275 US_DEBUGP("-- short transfer\n"); 276 return USB_STOR_XFER_SHORT; 277 } 278 279 US_DEBUGP("-- transfer complete\n"); 280 return USB_STOR_XFER_GOOD; 281 282 /* stalled */ 283 case -EPIPE: 284 /* for control endpoints, (used by CB[I]) a stall indicates 285 * a failed command */ 286 if (usb_pipecontrol(pipe)) { 287 US_DEBUGP("-- stall on control pipe\n"); 288 return USB_STOR_XFER_STALLED; 289 } 290 291 /* for other sorts of endpoint, clear the stall */ 292 US_DEBUGP("clearing endpoint halt for pipe 0x%x\n", pipe); 293 if (usb_stor_clear_halt(us, pipe) < 0) 294 return USB_STOR_XFER_ERROR; 295 return USB_STOR_XFER_STALLED; 296 297 /* timeout or excessively long NAK */ 298 case -ETIMEDOUT: 299 US_DEBUGP("-- timeout or NAK\n"); 300 return USB_STOR_XFER_ERROR; 301 302 /* babble - the device tried to send more than we wanted to read */ 303 case -EOVERFLOW: 304 US_DEBUGP("-- babble\n"); 305 return USB_STOR_XFER_LONG; 306 307 /* the transfer was cancelled by abort, disconnect, or timeout */ 308 case -ECONNRESET: 309 US_DEBUGP("-- transfer cancelled\n"); 310 return USB_STOR_XFER_ERROR; 311 312 /* short scatter-gather read transfer */ 313 case -EREMOTEIO: 314 US_DEBUGP("-- short read transfer\n"); 315 return USB_STOR_XFER_SHORT; 316 317 /* abort or disconnect in progress */ 318 case -EIO: 319 US_DEBUGP("-- abort or disconnect in progress\n"); 320 return USB_STOR_XFER_ERROR; 321 322 /* the catch-all error case */ 323 default: 324 US_DEBUGP("-- unknown error\n"); 325 return USB_STOR_XFER_ERROR; 326 } 327 } 328 329 /* 330 * Transfer one control message, without timeouts, but allowing early 331 * termination. Return codes are USB_STOR_XFER_xxx. 332 */ 333 int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe, 334 u8 request, u8 requesttype, u16 value, u16 index, 335 void *data, u16 size) 336 { 337 int result; 338 339 US_DEBUGP("%s: rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n", 340 __FUNCTION__, request, requesttype, 341 value, index, size); 342 343 /* fill in the devrequest structure */ 344 us->cr->bRequestType = requesttype; 345 us->cr->bRequest = request; 346 us->cr->wValue = cpu_to_le16(value); 347 us->cr->wIndex = cpu_to_le16(index); 348 us->cr->wLength = cpu_to_le16(size); 349 350 /* fill and submit the URB */ 351 usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe, 352 (unsigned char*) us->cr, data, size, 353 usb_stor_blocking_completion, NULL); 354 result = usb_stor_msg_common(us, 0); 355 356 return interpret_urb_result(us, pipe, size, result, 357 us->current_urb->actual_length); 358 } 359 360 /* 361 * Receive one interrupt buffer, without timeouts, but allowing early 362 * termination. Return codes are USB_STOR_XFER_xxx. 363 * 364 * This routine always uses us->recv_intr_pipe as the pipe and 365 * us->ep_bInterval as the interrupt interval. 366 */ 367 static int usb_stor_intr_transfer(struct us_data *us, void *buf, 368 unsigned int length) 369 { 370 int result; 371 unsigned int pipe = us->recv_intr_pipe; 372 unsigned int maxp; 373 374 US_DEBUGP("%s: xfer %u bytes\n", __FUNCTION__, length); 375 376 /* calculate the max packet size */ 377 maxp = usb_maxpacket(us->pusb_dev, pipe, usb_pipeout(pipe)); 378 if (maxp > length) 379 maxp = length; 380 381 /* fill and submit the URB */ 382 usb_fill_int_urb(us->current_urb, us->pusb_dev, pipe, buf, 383 maxp, usb_stor_blocking_completion, NULL, 384 us->ep_bInterval); 385 result = usb_stor_msg_common(us, 0); 386 387 return interpret_urb_result(us, pipe, length, result, 388 us->current_urb->actual_length); 389 } 390 391 /* 392 * Transfer one buffer via bulk pipe, without timeouts, but allowing early 393 * termination. Return codes are USB_STOR_XFER_xxx. If the bulk pipe 394 * stalls during the transfer, the halt is automatically cleared. 395 */ 396 int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe, 397 void *buf, unsigned int length, unsigned int *act_len) 398 { 399 int result; 400 401 US_DEBUGP("%s: xfer %u bytes\n", __FUNCTION__, length); 402 403 /* fill and submit the URB */ 404 usb_fill_bulk_urb(us->current_urb, us->pusb_dev, pipe, buf, length, 405 usb_stor_blocking_completion, NULL); 406 result = usb_stor_msg_common(us, 0); 407 408 /* store the actual length of the data transferred */ 409 if (act_len) 410 *act_len = us->current_urb->actual_length; 411 return interpret_urb_result(us, pipe, length, result, 412 us->current_urb->actual_length); 413 } 414 415 /* 416 * Transfer a scatter-gather list via bulk transfer 417 * 418 * This function does basically the same thing as usb_stor_bulk_transfer_buf() 419 * above, but it uses the usbcore scatter-gather library. 420 */ 421 static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe, 422 struct scatterlist *sg, int num_sg, unsigned int length, 423 unsigned int *act_len) 424 { 425 int result; 426 427 /* don't submit s-g requests during abort/disconnect processing */ 428 if (us->flags & ABORTING_OR_DISCONNECTING) 429 return USB_STOR_XFER_ERROR; 430 431 /* initialize the scatter-gather request block */ 432 US_DEBUGP("%s: xfer %u bytes, %d entries\n", __FUNCTION__, 433 length, num_sg); 434 result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0, 435 sg, num_sg, length, SLAB_NOIO); 436 if (result) { 437 US_DEBUGP("usb_sg_init returned %d\n", result); 438 return USB_STOR_XFER_ERROR; 439 } 440 441 /* since the block has been initialized successfully, it's now 442 * okay to cancel it */ 443 set_bit(US_FLIDX_SG_ACTIVE, &us->flags); 444 445 /* did an abort/disconnect occur during the submission? */ 446 if (us->flags & ABORTING_OR_DISCONNECTING) { 447 448 /* cancel the request, if it hasn't been cancelled already */ 449 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) { 450 US_DEBUGP("-- cancelling sg request\n"); 451 usb_sg_cancel(&us->current_sg); 452 } 453 } 454 455 /* wait for the completion of the transfer */ 456 usb_sg_wait(&us->current_sg); 457 clear_bit(US_FLIDX_SG_ACTIVE, &us->flags); 458 459 result = us->current_sg.status; 460 if (act_len) 461 *act_len = us->current_sg.bytes; 462 return interpret_urb_result(us, pipe, length, result, 463 us->current_sg.bytes); 464 } 465 466 /* 467 * Transfer an entire SCSI command's worth of data payload over the bulk 468 * pipe. 469 * 470 * Note that this uses usb_stor_bulk_transfer_buf() and 471 * usb_stor_bulk_transfer_sglist() to achieve its goals -- 472 * this function simply determines whether we're going to use 473 * scatter-gather or not, and acts appropriately. 474 */ 475 int usb_stor_bulk_transfer_sg(struct us_data* us, unsigned int pipe, 476 void *buf, unsigned int length_left, int use_sg, int *residual) 477 { 478 int result; 479 unsigned int partial; 480 481 /* are we scatter-gathering? */ 482 if (use_sg) { 483 /* use the usb core scatter-gather primitives */ 484 result = usb_stor_bulk_transfer_sglist(us, pipe, 485 (struct scatterlist *) buf, use_sg, 486 length_left, &partial); 487 length_left -= partial; 488 } else { 489 /* no scatter-gather, just make the request */ 490 result = usb_stor_bulk_transfer_buf(us, pipe, buf, 491 length_left, &partial); 492 length_left -= partial; 493 } 494 495 /* store the residual and return the error code */ 496 if (residual) 497 *residual = length_left; 498 return result; 499 } 500 501 /*********************************************************************** 502 * Transport routines 503 ***********************************************************************/ 504 505 /* Invoke the transport and basic error-handling/recovery methods 506 * 507 * This is used by the protocol layers to actually send the message to 508 * the device and receive the response. 509 */ 510 void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) 511 { 512 int need_auto_sense; 513 int result; 514 515 /* send the command to the transport layer */ 516 srb->resid = 0; 517 result = us->transport(srb, us); 518 519 /* if the command gets aborted by the higher layers, we need to 520 * short-circuit all other processing 521 */ 522 if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) { 523 US_DEBUGP("-- command was aborted\n"); 524 srb->result = DID_ABORT << 16; 525 goto Handle_Errors; 526 } 527 528 /* if there is a transport error, reset and don't auto-sense */ 529 if (result == USB_STOR_TRANSPORT_ERROR) { 530 US_DEBUGP("-- transport indicates error, resetting\n"); 531 srb->result = DID_ERROR << 16; 532 goto Handle_Errors; 533 } 534 535 /* if the transport provided its own sense data, don't auto-sense */ 536 if (result == USB_STOR_TRANSPORT_NO_SENSE) { 537 srb->result = SAM_STAT_CHECK_CONDITION; 538 return; 539 } 540 541 srb->result = SAM_STAT_GOOD; 542 543 /* Determine if we need to auto-sense 544 * 545 * I normally don't use a flag like this, but it's almost impossible 546 * to understand what's going on here if I don't. 547 */ 548 need_auto_sense = 0; 549 550 /* 551 * If we're running the CB transport, which is incapable 552 * of determining status on its own, we will auto-sense 553 * unless the operation involved a data-in transfer. Devices 554 * can signal most data-in errors by stalling the bulk-in pipe. 555 */ 556 if ((us->protocol == US_PR_CB || us->protocol == US_PR_DPCM_USB) && 557 srb->sc_data_direction != DMA_FROM_DEVICE) { 558 US_DEBUGP("-- CB transport device requiring auto-sense\n"); 559 need_auto_sense = 1; 560 } 561 562 /* 563 * If we have a failure, we're going to do a REQUEST_SENSE 564 * automatically. Note that we differentiate between a command 565 * "failure" and an "error" in the transport mechanism. 566 */ 567 if (result == USB_STOR_TRANSPORT_FAILED) { 568 US_DEBUGP("-- transport indicates command failure\n"); 569 need_auto_sense = 1; 570 } 571 572 /* 573 * A short transfer on a command where we don't expect it 574 * is unusual, but it doesn't mean we need to auto-sense. 575 */ 576 if ((srb->resid > 0) && 577 !((srb->cmnd[0] == REQUEST_SENSE) || 578 (srb->cmnd[0] == INQUIRY) || 579 (srb->cmnd[0] == MODE_SENSE) || 580 (srb->cmnd[0] == LOG_SENSE) || 581 (srb->cmnd[0] == MODE_SENSE_10))) { 582 US_DEBUGP("-- unexpectedly short transfer\n"); 583 } 584 585 /* Now, if we need to do the auto-sense, let's do it */ 586 if (need_auto_sense) { 587 int temp_result; 588 void* old_request_buffer; 589 unsigned short old_sg; 590 unsigned old_request_bufflen; 591 unsigned char old_sc_data_direction; 592 unsigned char old_cmd_len; 593 unsigned char old_cmnd[MAX_COMMAND_SIZE]; 594 int old_resid; 595 596 US_DEBUGP("Issuing auto-REQUEST_SENSE\n"); 597 598 /* save the old command */ 599 memcpy(old_cmnd, srb->cmnd, MAX_COMMAND_SIZE); 600 old_cmd_len = srb->cmd_len; 601 602 /* set the command and the LUN */ 603 memset(srb->cmnd, 0, MAX_COMMAND_SIZE); 604 srb->cmnd[0] = REQUEST_SENSE; 605 srb->cmnd[1] = old_cmnd[1] & 0xE0; 606 srb->cmnd[4] = 18; 607 608 /* FIXME: we must do the protocol translation here */ 609 if (us->subclass == US_SC_RBC || us->subclass == US_SC_SCSI) 610 srb->cmd_len = 6; 611 else 612 srb->cmd_len = 12; 613 614 /* set the transfer direction */ 615 old_sc_data_direction = srb->sc_data_direction; 616 srb->sc_data_direction = DMA_FROM_DEVICE; 617 618 /* use the new buffer we have */ 619 old_request_buffer = srb->request_buffer; 620 srb->request_buffer = us->sensebuf; 621 622 /* set the buffer length for transfer */ 623 old_request_bufflen = srb->request_bufflen; 624 srb->request_bufflen = US_SENSE_SIZE; 625 626 /* set up for no scatter-gather use */ 627 old_sg = srb->use_sg; 628 srb->use_sg = 0; 629 630 /* issue the auto-sense command */ 631 old_resid = srb->resid; 632 srb->resid = 0; 633 temp_result = us->transport(us->srb, us); 634 635 /* let's clean up right away */ 636 memcpy(srb->sense_buffer, us->sensebuf, US_SENSE_SIZE); 637 srb->resid = old_resid; 638 srb->request_buffer = old_request_buffer; 639 srb->request_bufflen = old_request_bufflen; 640 srb->use_sg = old_sg; 641 srb->sc_data_direction = old_sc_data_direction; 642 srb->cmd_len = old_cmd_len; 643 memcpy(srb->cmnd, old_cmnd, MAX_COMMAND_SIZE); 644 645 if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) { 646 US_DEBUGP("-- auto-sense aborted\n"); 647 srb->result = DID_ABORT << 16; 648 goto Handle_Errors; 649 } 650 if (temp_result != USB_STOR_TRANSPORT_GOOD) { 651 US_DEBUGP("-- auto-sense failure\n"); 652 653 /* we skip the reset if this happens to be a 654 * multi-target device, since failure of an 655 * auto-sense is perfectly valid 656 */ 657 srb->result = DID_ERROR << 16; 658 if (!(us->flags & US_FL_SCM_MULT_TARG)) 659 goto Handle_Errors; 660 return; 661 } 662 663 US_DEBUGP("-- Result from auto-sense is %d\n", temp_result); 664 US_DEBUGP("-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n", 665 srb->sense_buffer[0], 666 srb->sense_buffer[2] & 0xf, 667 srb->sense_buffer[12], 668 srb->sense_buffer[13]); 669 #ifdef CONFIG_USB_STORAGE_DEBUG 670 usb_stor_show_sense( 671 srb->sense_buffer[2] & 0xf, 672 srb->sense_buffer[12], 673 srb->sense_buffer[13]); 674 #endif 675 676 /* set the result so the higher layers expect this data */ 677 srb->result = SAM_STAT_CHECK_CONDITION; 678 679 /* If things are really okay, then let's show that. Zero 680 * out the sense buffer so the higher layers won't realize 681 * we did an unsolicited auto-sense. */ 682 if (result == USB_STOR_TRANSPORT_GOOD && 683 /* Filemark 0, ignore EOM, ILI 0, no sense */ 684 (srb->sense_buffer[2] & 0xaf) == 0 && 685 /* No ASC or ASCQ */ 686 srb->sense_buffer[12] == 0 && 687 srb->sense_buffer[13] == 0) { 688 srb->result = SAM_STAT_GOOD; 689 srb->sense_buffer[0] = 0x0; 690 } 691 } 692 693 /* Did we transfer less than the minimum amount required? */ 694 if (srb->result == SAM_STAT_GOOD && 695 srb->request_bufflen - srb->resid < srb->underflow) 696 srb->result = (DID_ERROR << 16) | (SUGGEST_RETRY << 24); 697 698 return; 699 700 /* Error and abort processing: try to resynchronize with the device 701 * by issuing a port reset. If that fails, try a class-specific 702 * device reset. */ 703 Handle_Errors: 704 705 /* Set the RESETTING bit, and clear the ABORTING bit so that 706 * the reset may proceed. */ 707 scsi_lock(us_to_host(us)); 708 set_bit(US_FLIDX_RESETTING, &us->flags); 709 clear_bit(US_FLIDX_ABORTING, &us->flags); 710 scsi_unlock(us_to_host(us)); 711 712 /* We must release the device lock because the pre_reset routine 713 * will want to acquire it. */ 714 mutex_unlock(&us->dev_mutex); 715 result = usb_stor_port_reset(us); 716 mutex_lock(&us->dev_mutex); 717 718 if (result < 0) { 719 scsi_lock(us_to_host(us)); 720 usb_stor_report_device_reset(us); 721 scsi_unlock(us_to_host(us)); 722 us->transport_reset(us); 723 } 724 clear_bit(US_FLIDX_RESETTING, &us->flags); 725 } 726 727 /* Stop the current URB transfer */ 728 void usb_stor_stop_transport(struct us_data *us) 729 { 730 US_DEBUGP("%s called\n", __FUNCTION__); 731 732 /* If the state machine is blocked waiting for an URB, 733 * let's wake it up. The test_and_clear_bit() call 734 * guarantees that if a URB has just been submitted, 735 * it won't be cancelled more than once. */ 736 if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->flags)) { 737 US_DEBUGP("-- cancelling URB\n"); 738 usb_unlink_urb(us->current_urb); 739 } 740 741 /* If we are waiting for a scatter-gather operation, cancel it. */ 742 if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->flags)) { 743 US_DEBUGP("-- cancelling sg request\n"); 744 usb_sg_cancel(&us->current_sg); 745 } 746 } 747 748 /* 749 * Control/Bulk/Interrupt transport 750 */ 751 752 int usb_stor_CBI_transport(struct scsi_cmnd *srb, struct us_data *us) 753 { 754 unsigned int transfer_length = srb->request_bufflen; 755 unsigned int pipe = 0; 756 int result; 757 758 /* COMMAND STAGE */ 759 /* let's send the command via the control pipe */ 760 result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe, 761 US_CBI_ADSC, 762 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 763 us->ifnum, srb->cmnd, srb->cmd_len); 764 765 /* check the return code for the command */ 766 US_DEBUGP("Call to usb_stor_ctrl_transfer() returned %d\n", result); 767 768 /* if we stalled the command, it means command failed */ 769 if (result == USB_STOR_XFER_STALLED) { 770 return USB_STOR_TRANSPORT_FAILED; 771 } 772 773 /* Uh oh... serious problem here */ 774 if (result != USB_STOR_XFER_GOOD) { 775 return USB_STOR_TRANSPORT_ERROR; 776 } 777 778 /* DATA STAGE */ 779 /* transfer the data payload for this command, if one exists*/ 780 if (transfer_length) { 781 pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? 782 us->recv_bulk_pipe : us->send_bulk_pipe; 783 result = usb_stor_bulk_transfer_sg(us, pipe, 784 srb->request_buffer, transfer_length, 785 srb->use_sg, &srb->resid); 786 US_DEBUGP("CBI data stage result is 0x%x\n", result); 787 788 /* if we stalled the data transfer it means command failed */ 789 if (result == USB_STOR_XFER_STALLED) 790 return USB_STOR_TRANSPORT_FAILED; 791 if (result > USB_STOR_XFER_STALLED) 792 return USB_STOR_TRANSPORT_ERROR; 793 } 794 795 /* STATUS STAGE */ 796 result = usb_stor_intr_transfer(us, us->iobuf, 2); 797 US_DEBUGP("Got interrupt data (0x%x, 0x%x)\n", 798 us->iobuf[0], us->iobuf[1]); 799 if (result != USB_STOR_XFER_GOOD) 800 return USB_STOR_TRANSPORT_ERROR; 801 802 /* UFI gives us ASC and ASCQ, like a request sense 803 * 804 * REQUEST_SENSE and INQUIRY don't affect the sense data on UFI 805 * devices, so we ignore the information for those commands. Note 806 * that this means we could be ignoring a real error on these 807 * commands, but that can't be helped. 808 */ 809 if (us->subclass == US_SC_UFI) { 810 if (srb->cmnd[0] == REQUEST_SENSE || 811 srb->cmnd[0] == INQUIRY) 812 return USB_STOR_TRANSPORT_GOOD; 813 if (us->iobuf[0]) 814 goto Failed; 815 return USB_STOR_TRANSPORT_GOOD; 816 } 817 818 /* If not UFI, we interpret the data as a result code 819 * The first byte should always be a 0x0. 820 * 821 * Some bogus devices don't follow that rule. They stuff the ASC 822 * into the first byte -- so if it's non-zero, call it a failure. 823 */ 824 if (us->iobuf[0]) { 825 US_DEBUGP("CBI IRQ data showed reserved bType 0x%x\n", 826 us->iobuf[0]); 827 goto Failed; 828 829 } 830 831 /* The second byte & 0x0F should be 0x0 for good, otherwise error */ 832 switch (us->iobuf[1] & 0x0F) { 833 case 0x00: 834 return USB_STOR_TRANSPORT_GOOD; 835 case 0x01: 836 goto Failed; 837 } 838 return USB_STOR_TRANSPORT_ERROR; 839 840 /* the CBI spec requires that the bulk pipe must be cleared 841 * following any data-in/out command failure (section 2.4.3.1.3) 842 */ 843 Failed: 844 if (pipe) 845 usb_stor_clear_halt(us, pipe); 846 return USB_STOR_TRANSPORT_FAILED; 847 } 848 849 /* 850 * Control/Bulk transport 851 */ 852 int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us) 853 { 854 unsigned int transfer_length = srb->request_bufflen; 855 int result; 856 857 /* COMMAND STAGE */ 858 /* let's send the command via the control pipe */ 859 result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe, 860 US_CBI_ADSC, 861 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 862 us->ifnum, srb->cmnd, srb->cmd_len); 863 864 /* check the return code for the command */ 865 US_DEBUGP("Call to usb_stor_ctrl_transfer() returned %d\n", result); 866 867 /* if we stalled the command, it means command failed */ 868 if (result == USB_STOR_XFER_STALLED) { 869 return USB_STOR_TRANSPORT_FAILED; 870 } 871 872 /* Uh oh... serious problem here */ 873 if (result != USB_STOR_XFER_GOOD) { 874 return USB_STOR_TRANSPORT_ERROR; 875 } 876 877 /* DATA STAGE */ 878 /* transfer the data payload for this command, if one exists*/ 879 if (transfer_length) { 880 unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? 881 us->recv_bulk_pipe : us->send_bulk_pipe; 882 result = usb_stor_bulk_transfer_sg(us, pipe, 883 srb->request_buffer, transfer_length, 884 srb->use_sg, &srb->resid); 885 US_DEBUGP("CB data stage result is 0x%x\n", result); 886 887 /* if we stalled the data transfer it means command failed */ 888 if (result == USB_STOR_XFER_STALLED) 889 return USB_STOR_TRANSPORT_FAILED; 890 if (result > USB_STOR_XFER_STALLED) 891 return USB_STOR_TRANSPORT_ERROR; 892 } 893 894 /* STATUS STAGE */ 895 /* NOTE: CB does not have a status stage. Silly, I know. So 896 * we have to catch this at a higher level. 897 */ 898 return USB_STOR_TRANSPORT_GOOD; 899 } 900 901 /* 902 * Bulk only transport 903 */ 904 905 /* Determine what the maximum LUN supported is */ 906 int usb_stor_Bulk_max_lun(struct us_data *us) 907 { 908 int result; 909 910 /* issue the command */ 911 us->iobuf[0] = 0; 912 result = usb_stor_control_msg(us, us->recv_ctrl_pipe, 913 US_BULK_GET_MAX_LUN, 914 USB_DIR_IN | USB_TYPE_CLASS | 915 USB_RECIP_INTERFACE, 916 0, us->ifnum, us->iobuf, 1, HZ); 917 918 US_DEBUGP("GetMaxLUN command result is %d, data is %d\n", 919 result, us->iobuf[0]); 920 921 /* if we have a successful request, return the result */ 922 if (result > 0) 923 return us->iobuf[0]; 924 925 /* 926 * Some devices (i.e. Iomega Zip100) need this -- apparently 927 * the bulk pipes get STALLed when the GetMaxLUN request is 928 * processed. This is, in theory, harmless to all other devices 929 * (regardless of if they stall or not). 930 */ 931 if (result == -EPIPE) { 932 usb_stor_clear_halt(us, us->recv_bulk_pipe); 933 usb_stor_clear_halt(us, us->send_bulk_pipe); 934 } 935 936 /* 937 * Some devices don't like GetMaxLUN. They may STALL the control 938 * pipe, they may return a zero-length result, they may do nothing at 939 * all and timeout, or they may fail in even more bizarrely creative 940 * ways. In these cases the best approach is to use the default 941 * value: only one LUN. 942 */ 943 return 0; 944 } 945 946 int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us) 947 { 948 struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf; 949 struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf; 950 unsigned int transfer_length = srb->request_bufflen; 951 unsigned int residue; 952 int result; 953 int fake_sense = 0; 954 unsigned int cswlen; 955 unsigned int cbwlen = US_BULK_CB_WRAP_LEN; 956 957 /* Take care of BULK32 devices; set extra byte to 0 */ 958 if ( unlikely(us->flags & US_FL_BULK32)) { 959 cbwlen = 32; 960 us->iobuf[31] = 0; 961 } 962 963 /* set up the command wrapper */ 964 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN); 965 bcb->DataTransferLength = cpu_to_le32(transfer_length); 966 bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ? 1 << 7 : 0; 967 bcb->Tag = ++us->tag; 968 bcb->Lun = srb->device->lun; 969 if (us->flags & US_FL_SCM_MULT_TARG) 970 bcb->Lun |= srb->device->id << 4; 971 bcb->Length = srb->cmd_len; 972 973 /* copy the command payload */ 974 memset(bcb->CDB, 0, sizeof(bcb->CDB)); 975 memcpy(bcb->CDB, srb->cmnd, bcb->Length); 976 977 /* send it to out endpoint */ 978 US_DEBUGP("Bulk Command S 0x%x T 0x%x L %d F %d Trg %d LUN %d CL %d\n", 979 le32_to_cpu(bcb->Signature), bcb->Tag, 980 le32_to_cpu(bcb->DataTransferLength), bcb->Flags, 981 (bcb->Lun >> 4), (bcb->Lun & 0x0F), 982 bcb->Length); 983 result = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe, 984 bcb, cbwlen, NULL); 985 US_DEBUGP("Bulk command transfer result=%d\n", result); 986 if (result != USB_STOR_XFER_GOOD) 987 return USB_STOR_TRANSPORT_ERROR; 988 989 /* DATA STAGE */ 990 /* send/receive data payload, if there is any */ 991 992 /* Some USB-IDE converter chips need a 100us delay between the 993 * command phase and the data phase. Some devices need a little 994 * more than that, probably because of clock rate inaccuracies. */ 995 if (unlikely(us->flags & US_FL_GO_SLOW)) 996 udelay(125); 997 998 if (transfer_length) { 999 unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? 1000 us->recv_bulk_pipe : us->send_bulk_pipe; 1001 result = usb_stor_bulk_transfer_sg(us, pipe, 1002 srb->request_buffer, transfer_length, 1003 srb->use_sg, &srb->resid); 1004 US_DEBUGP("Bulk data transfer result 0x%x\n", result); 1005 if (result == USB_STOR_XFER_ERROR) 1006 return USB_STOR_TRANSPORT_ERROR; 1007 1008 /* If the device tried to send back more data than the 1009 * amount requested, the spec requires us to transfer 1010 * the CSW anyway. Since there's no point retrying the 1011 * the command, we'll return fake sense data indicating 1012 * Illegal Request, Invalid Field in CDB. 1013 */ 1014 if (result == USB_STOR_XFER_LONG) 1015 fake_sense = 1; 1016 } 1017 1018 /* See flow chart on pg 15 of the Bulk Only Transport spec for 1019 * an explanation of how this code works. 1020 */ 1021 1022 /* get CSW for device status */ 1023 US_DEBUGP("Attempting to get CSW...\n"); 1024 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe, 1025 bcs, US_BULK_CS_WRAP_LEN, &cswlen); 1026 1027 /* Some broken devices add unnecessary zero-length packets to the 1028 * end of their data transfers. Such packets show up as 0-length 1029 * CSWs. If we encounter such a thing, try to read the CSW again. 1030 */ 1031 if (result == USB_STOR_XFER_SHORT && cswlen == 0) { 1032 US_DEBUGP("Received 0-length CSW; retrying...\n"); 1033 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe, 1034 bcs, US_BULK_CS_WRAP_LEN, &cswlen); 1035 } 1036 1037 /* did the attempt to read the CSW fail? */ 1038 if (result == USB_STOR_XFER_STALLED) { 1039 1040 /* get the status again */ 1041 US_DEBUGP("Attempting to get CSW (2nd try)...\n"); 1042 result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe, 1043 bcs, US_BULK_CS_WRAP_LEN, NULL); 1044 } 1045 1046 /* if we still have a failure at this point, we're in trouble */ 1047 US_DEBUGP("Bulk status result = %d\n", result); 1048 if (result != USB_STOR_XFER_GOOD) 1049 return USB_STOR_TRANSPORT_ERROR; 1050 1051 /* check bulk status */ 1052 residue = le32_to_cpu(bcs->Residue); 1053 US_DEBUGP("Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n", 1054 le32_to_cpu(bcs->Signature), bcs->Tag, 1055 residue, bcs->Status); 1056 if (bcs->Tag != us->tag || bcs->Status > US_BULK_STAT_PHASE) { 1057 US_DEBUGP("Bulk logical error\n"); 1058 return USB_STOR_TRANSPORT_ERROR; 1059 } 1060 1061 /* Some broken devices report odd signatures, so we do not check them 1062 * for validity against the spec. We store the first one we see, 1063 * and check subsequent transfers for validity against this signature. 1064 */ 1065 if (!us->bcs_signature) { 1066 us->bcs_signature = bcs->Signature; 1067 if (us->bcs_signature != cpu_to_le32(US_BULK_CS_SIGN)) 1068 US_DEBUGP("Learnt BCS signature 0x%08X\n", 1069 le32_to_cpu(us->bcs_signature)); 1070 } else if (bcs->Signature != us->bcs_signature) { 1071 US_DEBUGP("Signature mismatch: got %08X, expecting %08X\n", 1072 le32_to_cpu(bcs->Signature), 1073 le32_to_cpu(us->bcs_signature)); 1074 return USB_STOR_TRANSPORT_ERROR; 1075 } 1076 1077 /* try to compute the actual residue, based on how much data 1078 * was really transferred and what the device tells us */ 1079 if (residue) { 1080 if (!(us->flags & US_FL_IGNORE_RESIDUE)) { 1081 residue = min(residue, transfer_length); 1082 srb->resid = max(srb->resid, (int) residue); 1083 } 1084 } 1085 1086 /* based on the status code, we report good or bad */ 1087 switch (bcs->Status) { 1088 case US_BULK_STAT_OK: 1089 /* device babbled -- return fake sense data */ 1090 if (fake_sense) { 1091 memcpy(srb->sense_buffer, 1092 usb_stor_sense_invalidCDB, 1093 sizeof(usb_stor_sense_invalidCDB)); 1094 return USB_STOR_TRANSPORT_NO_SENSE; 1095 } 1096 1097 /* command good -- note that data could be short */ 1098 return USB_STOR_TRANSPORT_GOOD; 1099 1100 case US_BULK_STAT_FAIL: 1101 /* command failed */ 1102 return USB_STOR_TRANSPORT_FAILED; 1103 1104 case US_BULK_STAT_PHASE: 1105 /* phase error -- note that a transport reset will be 1106 * invoked by the invoke_transport() function 1107 */ 1108 return USB_STOR_TRANSPORT_ERROR; 1109 } 1110 1111 /* we should never get here, but if we do, we're in trouble */ 1112 return USB_STOR_TRANSPORT_ERROR; 1113 } 1114 1115 /*********************************************************************** 1116 * Reset routines 1117 ***********************************************************************/ 1118 1119 /* This is the common part of the device reset code. 1120 * 1121 * It's handy that every transport mechanism uses the control endpoint for 1122 * resets. 1123 * 1124 * Basically, we send a reset with a 5-second timeout, so we don't get 1125 * jammed attempting to do the reset. 1126 */ 1127 static int usb_stor_reset_common(struct us_data *us, 1128 u8 request, u8 requesttype, 1129 u16 value, u16 index, void *data, u16 size) 1130 { 1131 int result; 1132 int result2; 1133 1134 if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) { 1135 US_DEBUGP("No reset during disconnect\n"); 1136 return -EIO; 1137 } 1138 1139 result = usb_stor_control_msg(us, us->send_ctrl_pipe, 1140 request, requesttype, value, index, data, size, 1141 5*HZ); 1142 if (result < 0) { 1143 US_DEBUGP("Soft reset failed: %d\n", result); 1144 return result; 1145 } 1146 1147 /* Give the device some time to recover from the reset, 1148 * but don't delay disconnect processing. */ 1149 wait_event_interruptible_timeout(us->delay_wait, 1150 test_bit(US_FLIDX_DISCONNECTING, &us->flags), 1151 HZ*6); 1152 if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) { 1153 US_DEBUGP("Reset interrupted by disconnect\n"); 1154 return -EIO; 1155 } 1156 1157 US_DEBUGP("Soft reset: clearing bulk-in endpoint halt\n"); 1158 result = usb_stor_clear_halt(us, us->recv_bulk_pipe); 1159 1160 US_DEBUGP("Soft reset: clearing bulk-out endpoint halt\n"); 1161 result2 = usb_stor_clear_halt(us, us->send_bulk_pipe); 1162 1163 /* return a result code based on the result of the clear-halts */ 1164 if (result >= 0) 1165 result = result2; 1166 if (result < 0) 1167 US_DEBUGP("Soft reset failed\n"); 1168 else 1169 US_DEBUGP("Soft reset done\n"); 1170 return result; 1171 } 1172 1173 /* This issues a CB[I] Reset to the device in question 1174 */ 1175 #define CB_RESET_CMD_SIZE 12 1176 1177 int usb_stor_CB_reset(struct us_data *us) 1178 { 1179 US_DEBUGP("%s called\n", __FUNCTION__); 1180 1181 memset(us->iobuf, 0xFF, CB_RESET_CMD_SIZE); 1182 us->iobuf[0] = SEND_DIAGNOSTIC; 1183 us->iobuf[1] = 4; 1184 return usb_stor_reset_common(us, US_CBI_ADSC, 1185 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 1186 0, us->ifnum, us->iobuf, CB_RESET_CMD_SIZE); 1187 } 1188 1189 /* This issues a Bulk-only Reset to the device in question, including 1190 * clearing the subsequent endpoint halts that may occur. 1191 */ 1192 int usb_stor_Bulk_reset(struct us_data *us) 1193 { 1194 US_DEBUGP("%s called\n", __FUNCTION__); 1195 1196 return usb_stor_reset_common(us, US_BULK_RESET_REQUEST, 1197 USB_TYPE_CLASS | USB_RECIP_INTERFACE, 1198 0, us->ifnum, NULL, 0); 1199 } 1200 1201 /* Issue a USB port reset to the device. The caller must not hold 1202 * us->dev_mutex. 1203 */ 1204 int usb_stor_port_reset(struct us_data *us) 1205 { 1206 int result, rc_lock; 1207 1208 result = rc_lock = 1209 usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf); 1210 if (result < 0) 1211 US_DEBUGP("unable to lock device for reset: %d\n", result); 1212 else { 1213 /* Were we disconnected while waiting for the lock? */ 1214 if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) { 1215 result = -EIO; 1216 US_DEBUGP("No reset during disconnect\n"); 1217 } else { 1218 result = usb_reset_composite_device( 1219 us->pusb_dev, us->pusb_intf); 1220 US_DEBUGP("usb_reset_composite_device returns %d\n", 1221 result); 1222 } 1223 if (rc_lock) 1224 usb_unlock_device(us->pusb_dev); 1225 } 1226 return result; 1227 } 1228