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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Driver for USB Mass Storage compliant devices
  *
  * Current development and maintenance by:
  *   (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
  *
  * Developed with the assistance of:
  *   (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
  *   (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
  *   (c) 2002 Alan Stern <stern@rowland.org>
  *
  * Initial work by:
  *   (c) 1999 Michael Gee (michael@linuxspecific.com)
  *
  * This driver is based on the 'USB Mass Storage Class' document. This
  * describes in detail the protocol used to communicate with such
  * devices.  Clearly, the designers had SCSI and ATAPI commands in
  * mind when they created this document.  The commands are all very
  * similar to commands in the SCSI-II and ATAPI specifications.
  *
  * It is important to note that in a number of cases this class
  * exhibits class-specific exemptions from the USB specification.
  * Notably the usage of NAK, STALL and ACK differs from the norm, in
  * that they are used to communicate wait, failed and OK on commands.
  *
  * Also, for certain devices, the interrupt endpoint is used to convey
  * status of a command.
  */
 
 #include <linux/sched.h>
 #include <linux/gfp.h>
 #include <linux/errno.h>
 #include <linux/export.h>
 
 #include <linux/usb/quirks.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_eh.h>
 #include <scsi/scsi_device.h>
 
 #include "usb.h"
 #include "transport.h"
 #include "protocol.h"
 #include "scsiglue.h"
 #include "debug.h"
 
 #include <linux/blkdev.h>
 #include "../../scsi/sd.h"
 
 
 /***********************************************************************
  * Data transfer routines
  ***********************************************************************/
 
 /*
  * This is subtle, so pay attention:
  * ---------------------------------
  * We're very concerned about races with a command abort.  Hanging this code
  * is a sure fire way to hang the kernel.  (Note that this discussion applies
  * only to transactions resulting from a scsi queued-command, since only
  * these transactions are subject to a scsi abort.  Other transactions, such
  * as those occurring during device-specific initialization, must be handled
  * by a separate code path.)
  *
  * The abort function (usb_storage_command_abort() in scsiglue.c) first
  * sets the machine state and the ABORTING bit in us->dflags to prevent
  * new URBs from being submitted.  It then calls usb_stor_stop_transport()
  * below, which atomically tests-and-clears the URB_ACTIVE bit in us->dflags
  * to see if the current_urb needs to be stopped.  Likewise, the SG_ACTIVE
  * bit is tested to see if the current_sg scatter-gather request needs to be
  * stopped.  The timeout callback routine does much the same thing.
  *
  * When a disconnect occurs, the DISCONNECTING bit in us->dflags is set to
  * prevent new URBs from being submitted, and usb_stor_stop_transport() is
  * called to stop any ongoing requests.
  *
  * The submit function first verifies that the submitting is allowed
  * (neither ABORTING nor DISCONNECTING bits are set) and that the submit
  * completes without errors, and only then sets the URB_ACTIVE bit.  This
  * prevents the stop_transport() function from trying to cancel the URB
  * while the submit call is underway.  Next, the submit function must test
  * the flags to see if an abort or disconnect occurred during the submission
  * or before the URB_ACTIVE bit was set.  If so, it's essential to cancel
  * the URB if it hasn't been cancelled already (i.e., if the URB_ACTIVE bit
  * is still set).  Either way, the function must then wait for the URB to
  * finish.  Note that the URB can still be in progress even after a call to
  * usb_unlink_urb() returns.
  *
  * The idea is that (1) once the ABORTING or DISCONNECTING bit is set,
  * either the stop_transport() function or the submitting function
  * is guaranteed to call usb_unlink_urb() for an active URB,
  * and (2) test_and_clear_bit() prevents usb_unlink_urb() from being
  * called more than once or from being called during usb_submit_urb().
  */
 
 /*
  * This is the completion handler which will wake us up when an URB
  * completes.
  */
 static void usb_stor_blocking_completion(struct urb *urb)
 {
     struct completion *urb_done_ptr = urb->context;
 
     complete(urb_done_ptr);
 }
 
 /*
  * This is the common part of the URB message submission code
  *
  * All URBs from the usb-storage driver involved in handling a queued scsi
  * command _must_ pass through this function (or something like it) for the
  * abort mechanisms to work properly.
  */
 static int usb_stor_msg_common(struct us_data *us, int timeout)
 {
     struct completion urb_done;
     long timeleft;
     int status;
 
     /* don't submit URBs during abort processing */
     if (test_bit(US_FLIDX_ABORTING, &us->dflags))
         return -EIO;
 
     /* set up data structures for the wakeup system */
     init_completion(&urb_done);
 
     /* fill the common fields in the URB */
     us->current_urb->context = &urb_done;
     us->current_urb->transfer_flags = 0;
 
     /*
      * we assume that if transfer_buffer isn't us->iobuf then it
      * hasn't been mapped for DMA.  Yes, this is clunky, but it's
      * easier than always having the caller tell us whether the
      * transfer buffer has already been mapped.
      */
     if (us->current_urb->transfer_buffer == us->iobuf)
         us->current_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
     us->current_urb->transfer_dma = us->iobuf_dma;
 
     /* submit the URB */
     status = usb_submit_urb(us->current_urb, GFP_NOIO);
     if (status) {
         /* something went wrong */
         return status;
     }
 
     /*
      * since the URB has been submitted successfully, it's now okay
      * to cancel it
      */
     set_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
 
     /* did an abort occur during the submission? */
     if (test_bit(US_FLIDX_ABORTING, &us->dflags)) {
 
         /* cancel the URB, if it hasn't been cancelled already */
         if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
             usb_stor_dbg(us, "-- cancelling URB\n");
             usb_unlink_urb(us->current_urb);
         }
     }
  
     /* wait for the completion of the URB */
     timeleft = wait_for_completion_interruptible_timeout(
             &urb_done, timeout ? : MAX_SCHEDULE_TIMEOUT);
  
     clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags);
 
     if (timeleft <= 0) {
         usb_stor_dbg(us, "%s -- cancelling URB\n",
                  timeleft == 0 ? "Timeout" : "Signal");
         usb_kill_urb(us->current_urb);
     }
 
     /* return the URB status */
     return us->current_urb->status;
 }
 
 /*
  * Transfer one control message, with timeouts, and allowing early
  * termination.  Return codes are usual -Exxx, *not* USB_STOR_XFER_xxx.
  */
 int usb_stor_control_msg(struct us_data *us, unsigned int pipe,
          u8 request, u8 requesttype, u16 value, u16 index, 
          void *data, u16 size, int timeout)
 {
     int status;
 
     usb_stor_dbg(us, "rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
              request, requesttype, value, index, size);
 
     /* fill in the devrequest structure */
     us->cr->bRequestType = requesttype;
     us->cr->bRequest = request;
     us->cr->wValue = cpu_to_le16(value);
     us->cr->wIndex = cpu_to_le16(index);
     us->cr->wLength = cpu_to_le16(size);
 
     /* fill and submit the URB */
     usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe, 
              (unsigned char*) us->cr, data, size, 
              usb_stor_blocking_completion, NULL);
     status = usb_stor_msg_common(us, timeout);
 
     /* return the actual length of the data transferred if no error */
     if (status == 0)
         status = us->current_urb->actual_length;
     return status;
 }
 EXPORT_SYMBOL_GPL(usb_stor_control_msg);
 
 /*
  * This is a version of usb_clear_halt() that allows early termination and
  * doesn't read the status from the device -- this is because some devices
  * crash their internal firmware when the status is requested after a halt.
  *
  * A definitive list of these 'bad' devices is too difficult to maintain or
  * make complete enough to be useful.  This problem was first observed on the
  * Hagiwara FlashGate DUAL unit.  However, bus traces reveal that neither
  * MacOS nor Windows checks the status after clearing a halt.
  *
  * Since many vendors in this space limit their testing to interoperability
  * with these two OSes, specification violations like this one are common.
  */
 int usb_stor_clear_halt(struct us_data *us, unsigned int pipe)
 {
     int result;
     int endp = usb_pipeendpoint(pipe);
 
     if (usb_pipein (pipe))
         endp |= USB_DIR_IN;
 
     result = usb_stor_control_msg(us, us->send_ctrl_pipe,
         USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
         USB_ENDPOINT_HALT, endp,
         NULL, 0, 3*HZ);
 
     if (result >= 0)
         usb_reset_endpoint(us->pusb_dev, endp);
 
     usb_stor_dbg(us, "result = %d\n", result);
     return result;
 }
 EXPORT_SYMBOL_GPL(usb_stor_clear_halt);
 
 
 /*
  * Interpret the results of a URB transfer
  *
  * This function prints appropriate debugging messages, clears halts on
  * non-control endpoints, and translates the status to the corresponding
  * USB_STOR_XFER_xxx return code.
  */
 static int interpret_urb_result(struct us_data *us, unsigned int pipe,
         unsigned int length, int result, unsigned int partial)
 {
     usb_stor_dbg(us, "Status code %d; transferred %u/%u\n",
              result, partial, length);
     switch (result) {
 
     /* no error code; did we send all the data? */
     case 0:
         if (partial != length) {
             usb_stor_dbg(us, "-- short transfer\n");
             return USB_STOR_XFER_SHORT;
         }
 
         usb_stor_dbg(us, "-- transfer complete\n");
         return USB_STOR_XFER_GOOD;
 
     /* stalled */
     case -EPIPE:
         /*
          * for control endpoints, (used by CB[I]) a stall indicates
          * a failed command
          */
         if (usb_pipecontrol(pipe)) {
             usb_stor_dbg(us, "-- stall on control pipe\n");
             return USB_STOR_XFER_STALLED;
         }
 
         /* for other sorts of endpoint, clear the stall */
         usb_stor_dbg(us, "clearing endpoint halt for pipe 0x%x\n",
                  pipe);
         if (usb_stor_clear_halt(us, pipe) < 0)
             return USB_STOR_XFER_ERROR;
         return USB_STOR_XFER_STALLED;
 
     /* babble - the device tried to send more than we wanted to read */
     case -EOVERFLOW:
         usb_stor_dbg(us, "-- babble\n");
         return USB_STOR_XFER_LONG;
 
     /* the transfer was cancelled by abort, disconnect, or timeout */
     case -ECONNRESET:
         usb_stor_dbg(us, "-- transfer cancelled\n");
         return USB_STOR_XFER_ERROR;
 
     /* short scatter-gather read transfer */
     case -EREMOTEIO:
         usb_stor_dbg(us, "-- short read transfer\n");
         return USB_STOR_XFER_SHORT;
 
     /* abort or disconnect in progress */
     case -EIO:
         usb_stor_dbg(us, "-- abort or disconnect in progress\n");
         return USB_STOR_XFER_ERROR;
 
     /* the catch-all error case */
     default:
         usb_stor_dbg(us, "-- unknown error\n");
         return USB_STOR_XFER_ERROR;
     }
 }
 
 /*
  * Transfer one control message, without timeouts, but allowing early
  * termination.  Return codes are USB_STOR_XFER_xxx.
  */
 int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe,
         u8 request, u8 requesttype, u16 value, u16 index,
         void *data, u16 size)
 {
     int result;
 
     usb_stor_dbg(us, "rq=%02x rqtype=%02x value=%04x index=%02x len=%u\n",
              request, requesttype, value, index, size);
 
     /* fill in the devrequest structure */
     us->cr->bRequestType = requesttype;
     us->cr->bRequest = request;
     us->cr->wValue = cpu_to_le16(value);
     us->cr->wIndex = cpu_to_le16(index);
     us->cr->wLength = cpu_to_le16(size);
 
     /* fill and submit the URB */
     usb_fill_control_urb(us->current_urb, us->pusb_dev, pipe, 
              (unsigned char*) us->cr, data, size, 
              usb_stor_blocking_completion, NULL);
     result = usb_stor_msg_common(us, 0);
 
     return interpret_urb_result(us, pipe, size, result,
             us->current_urb->actual_length);
 }
 EXPORT_SYMBOL_GPL(usb_stor_ctrl_transfer);
 
 /*
  * Receive one interrupt buffer, without timeouts, but allowing early
  * termination.  Return codes are USB_STOR_XFER_xxx.
  *
  * This routine always uses us->recv_intr_pipe as the pipe and
  * us->ep_bInterval as the interrupt interval.
  */
 static int usb_stor_intr_transfer(struct us_data *us, void *buf,
                   unsigned int length)
 {
     int result;
     unsigned int pipe = us->recv_intr_pipe;
     unsigned int maxp;
 
     usb_stor_dbg(us, "xfer %u bytes\n", length);
 
     /* calculate the max packet size */
     maxp = usb_maxpacket(us->pusb_dev, pipe);
     if (maxp > length)
         maxp = length;
 
     /* fill and submit the URB */
     usb_fill_int_urb(us->current_urb, us->pusb_dev, pipe, buf,
             maxp, usb_stor_blocking_completion, NULL,
             us->ep_bInterval);
     result = usb_stor_msg_common(us, 0);
 
     return interpret_urb_result(us, pipe, length, result,
             us->current_urb->actual_length);
 }
 
 /*
  * Transfer one buffer via bulk pipe, without timeouts, but allowing early
  * termination.  Return codes are USB_STOR_XFER_xxx.  If the bulk pipe
  * stalls during the transfer, the halt is automatically cleared.
  */
 int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe,
     void *buf, unsigned int length, unsigned int *act_len)
 {
     int result;
 
     usb_stor_dbg(us, "xfer %u bytes\n", length);
 
     /* fill and submit the URB */
     usb_fill_bulk_urb(us->current_urb, us->pusb_dev, pipe, buf, length,
               usb_stor_blocking_completion, NULL);
     result = usb_stor_msg_common(us, 0);
 
     /* store the actual length of the data transferred */
     if (act_len)
         *act_len = us->current_urb->actual_length;
     return interpret_urb_result(us, pipe, length, result, 
             us->current_urb->actual_length);
 }
 EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_buf);
 
 /*
  * Transfer a scatter-gather list via bulk transfer
  *
  * This function does basically the same thing as usb_stor_bulk_transfer_buf()
  * above, but it uses the usbcore scatter-gather library.
  */
 static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
         struct scatterlist *sg, int num_sg, unsigned int length,
         unsigned int *act_len)
 {
     int result;
 
     /* don't submit s-g requests during abort processing */
     if (test_bit(US_FLIDX_ABORTING, &us->dflags))
         goto usb_stor_xfer_error;
 
     /* initialize the scatter-gather request block */
     usb_stor_dbg(us, "xfer %u bytes, %d entries\n", length, num_sg);
     result = usb_sg_init(&us->current_sg, us->pusb_dev, pipe, 0,
             sg, num_sg, length, GFP_NOIO);
     if (result) {
         usb_stor_dbg(us, "usb_sg_init returned %d\n", result);
         goto usb_stor_xfer_error;
     }
 
     /*
      * since the block has been initialized successfully, it's now
      * okay to cancel it
      */
     set_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
 
     /* did an abort occur during the submission? */
     if (test_bit(US_FLIDX_ABORTING, &us->dflags)) {
 
         /* cancel the request, if it hasn't been cancelled already */
         if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
             usb_stor_dbg(us, "-- cancelling sg request\n");
             usb_sg_cancel(&us->current_sg);
         }
     }
 
     /* wait for the completion of the transfer */
     usb_sg_wait(&us->current_sg);
     clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags);
 
     result = us->current_sg.status;
     if (act_len)
         *act_len = us->current_sg.bytes;
     return interpret_urb_result(us, pipe, length, result,
             us->current_sg.bytes);
 
 usb_stor_xfer_error:
     if (act_len)
         *act_len = 0;
     return USB_STOR_XFER_ERROR;
 }
 
 /*
  * Common used function. Transfer a complete command
  * via usb_stor_bulk_transfer_sglist() above. Set cmnd resid
  */
 int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe,
               struct scsi_cmnd* srb)
 {
     unsigned int partial;
     int result = usb_stor_bulk_transfer_sglist(us, pipe, scsi_sglist(srb),
                       scsi_sg_count(srb), scsi_bufflen(srb),
                       &partial);
 
     scsi_set_resid(srb, scsi_bufflen(srb) - partial);
     return result;
 }
 EXPORT_SYMBOL_GPL(usb_stor_bulk_srb);
 
 /*
  * Transfer an entire SCSI command's worth of data payload over the bulk
  * pipe.
  *
  * Note that this uses usb_stor_bulk_transfer_buf() and
  * usb_stor_bulk_transfer_sglist() to achieve its goals --
  * this function simply determines whether we're going to use
  * scatter-gather or not, and acts appropriately.
  */
 int usb_stor_bulk_transfer_sg(struct us_data* us, unsigned int pipe,
         void *buf, unsigned int length_left, int use_sg, int *residual)
 {
     int result;
     unsigned int partial;
 
     /* are we scatter-gathering? */
     if (use_sg) {
         /* use the usb core scatter-gather primitives */
         result = usb_stor_bulk_transfer_sglist(us, pipe,
                 (struct scatterlist *) buf, use_sg,
                 length_left, &partial);
         length_left -= partial;
     } else {
         /* no scatter-gather, just make the request */
         result = usb_stor_bulk_transfer_buf(us, pipe, buf, 
                 length_left, &partial);
         length_left -= partial;
     }
 
     /* store the residual and return the error code */
     if (residual)
         *residual = length_left;
     return result;
 }
 EXPORT_SYMBOL_GPL(usb_stor_bulk_transfer_sg);
 
 /***********************************************************************
  * Transport routines
  ***********************************************************************/
 
 /*
  * There are so many devices that report the capacity incorrectly,
  * this routine was written to counteract some of the resulting
  * problems.
  */
 static void last_sector_hacks(struct us_data *us, struct scsi_cmnd *srb)
 {
     struct gendisk *disk;
     struct scsi_disk *sdkp;
     u32 sector;
 
     /* To Report "Medium Error: Record Not Found */
     static unsigned char record_not_found[18] = {
         [0] = 0x70,         /* current error */
         [2] = MEDIUM_ERROR,     /* = 0x03 */
         [7] = 0x0a,         /* additional length */
         [12]    = 0x14          /* Record Not Found */
     };
 
     /*
      * If last-sector problems can't occur, whether because the
      * capacity was already decremented or because the device is
      * known to report the correct capacity, then we don't need
      * to do anything.
      */
     if (!us->use_last_sector_hacks)
         return;
 
     /* Was this command a READ(10) or a WRITE(10)? */
     if (srb->cmnd[0] != READ_10 && srb->cmnd[0] != WRITE_10)
         goto done;
 
     /* Did this command access the last sector? */
     sector = (srb->cmnd[2] << 24) | (srb->cmnd[3] << 16) |
             (srb->cmnd[4] << 8) | (srb->cmnd[5]);
     disk = scsi_cmd_to_rq(srb)->q->disk;
     if (!disk)
         goto done;
     sdkp = scsi_disk(disk);
     if (!sdkp)
         goto done;
     if (sector + 1 != sdkp->capacity)
         goto done;
 
     if (srb->result == SAM_STAT_GOOD && scsi_get_resid(srb) == 0) {
 
         /*
          * The command succeeded.  We know this device doesn't
          * have the last-sector bug, so stop checking it.
          */
         us->use_last_sector_hacks = 0;
 
     } else {
         /*
          * The command failed.  Allow up to 3 retries in case this
          * is some normal sort of failure.  After that, assume the
          * capacity is wrong and we're trying to access the sector
          * beyond the end.  Replace the result code and sense data
          * with values that will cause the SCSI core to fail the
          * command immediately, instead of going into an infinite
          * (or even just a very long) retry loop.
          */
         if (++us->last_sector_retries < 3)
             return;
         srb->result = SAM_STAT_CHECK_CONDITION;
         memcpy(srb->sense_buffer, record_not_found,
                 sizeof(record_not_found));
     }
 
  done:
     /*
      * Don't reset the retry counter for TEST UNIT READY commands,
      * because they get issued after device resets which might be
      * caused by a failed last-sector access.
      */
     if (srb->cmnd[0] != TEST_UNIT_READY)
         us->last_sector_retries = 0;
 }
 
 /*
  * Invoke the transport and basic error-handling/recovery methods
  *
  * This is used by the protocol layers to actually send the message to
  * the device and receive the response.
  */
 void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 {
     int need_auto_sense;
     int result;
 
     /* send the command to the transport layer */
     scsi_set_resid(srb, 0);
     result = us->transport(srb, us);
 
     /*
      * if the command gets aborted by the higher layers, we need to
      * short-circuit all other processing
      */
     if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
         usb_stor_dbg(us, "-- command was aborted\n");
         srb->result = DID_ABORT << 16;
         goto Handle_Errors;
     }
 
     /* if there is a transport error, reset and don't auto-sense */
     if (result == USB_STOR_TRANSPORT_ERROR) {
         usb_stor_dbg(us, "-- transport indicates error, resetting\n");
         srb->result = DID_ERROR << 16;
         goto Handle_Errors;
     }
 
     /* if the transport provided its own sense data, don't auto-sense */
     if (result == USB_STOR_TRANSPORT_NO_SENSE) {
         srb->result = SAM_STAT_CHECK_CONDITION;
         last_sector_hacks(us, srb);
         return;
     }
 
     srb->result = SAM_STAT_GOOD;
 
     /*
      * Determine if we need to auto-sense
      *
      * I normally don't use a flag like this, but it's almost impossible
      * to understand what's going on here if I don't.
      */
     need_auto_sense = 0;
 
     /*
      * If we're running the CB transport, which is incapable
      * of determining status on its own, we will auto-sense
      * unless the operation involved a data-in transfer.  Devices
      * can signal most data-in errors by stalling the bulk-in pipe.
      */
     if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_DPCM_USB) &&
             srb->sc_data_direction != DMA_FROM_DEVICE) {
         usb_stor_dbg(us, "-- CB transport device requiring auto-sense\n");
         need_auto_sense = 1;
     }
 
     /* Some devices (Kindle) require another command after SYNC CACHE */
     if ((us->fflags & US_FL_SENSE_AFTER_SYNC) &&
             srb->cmnd[0] == SYNCHRONIZE_CACHE) {
         usb_stor_dbg(us, "-- sense after SYNC CACHE\n");
         need_auto_sense = 1;
     }
 
     /*
      * If we have a failure, we're going to do a REQUEST_SENSE 
      * automatically.  Note that we differentiate between a command
      * "failure" and an "error" in the transport mechanism.
      */
     if (result == USB_STOR_TRANSPORT_FAILED) {
         usb_stor_dbg(us, "-- transport indicates command failure\n");
         need_auto_sense = 1;
     }
 
     /*
      * Determine if this device is SAT by seeing if the
      * command executed successfully.  Otherwise we'll have
      * to wait for at least one CHECK_CONDITION to determine
      * SANE_SENSE support
      */
     if (unlikely((srb->cmnd[0] == ATA_16 || srb->cmnd[0] == ATA_12) &&
         result == USB_STOR_TRANSPORT_GOOD &&
         !(us->fflags & US_FL_SANE_SENSE) &&
         !(us->fflags & US_FL_BAD_SENSE) &&
         !(srb->cmnd[2] & 0x20))) {
         usb_stor_dbg(us, "-- SAT supported, increasing auto-sense\n");
         us->fflags |= US_FL_SANE_SENSE;
     }
 
     /*
      * A short transfer on a command where we don't expect it
      * is unusual, but it doesn't mean we need to auto-sense.
      */
     if ((scsi_get_resid(srb) > 0) &&
         !((srb->cmnd[0] == REQUEST_SENSE) ||
           (srb->cmnd[0] == INQUIRY) ||
           (srb->cmnd[0] == MODE_SENSE) ||
           (srb->cmnd[0] == LOG_SENSE) ||
           (srb->cmnd[0] == MODE_SENSE_10))) {
         usb_stor_dbg(us, "-- unexpectedly short transfer\n");
     }
 
     /* Now, if we need to do the auto-sense, let's do it */
     if (need_auto_sense) {
         int temp_result;
         struct scsi_eh_save ses;
         int sense_size = US_SENSE_SIZE;
         struct scsi_sense_hdr sshdr;
         const u8 *scdd;
         u8 fm_ili;
 
         /* device supports and needs bigger sense buffer */
         if (us->fflags & US_FL_SANE_SENSE)
             sense_size = ~0;
 Retry_Sense:
         usb_stor_dbg(us, "Issuing auto-REQUEST_SENSE\n");
 
         scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sense_size);
 
         /* FIXME: we must do the protocol translation here */
         if (us->subclass == USB_SC_RBC || us->subclass == USB_SC_SCSI ||
                 us->subclass == USB_SC_CYP_ATACB)
             srb->cmd_len = 6;
         else
             srb->cmd_len = 12;
 
         /* issue the auto-sense command */
         scsi_set_resid(srb, 0);
         temp_result = us->transport(us->srb, us);
 
         /* let's clean up right away */
         scsi_eh_restore_cmnd(srb, &ses);
 
         if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
             usb_stor_dbg(us, "-- auto-sense aborted\n");
             srb->result = DID_ABORT << 16;
 
             /* If SANE_SENSE caused this problem, disable it */
             if (sense_size != US_SENSE_SIZE) {
                 us->fflags &= ~US_FL_SANE_SENSE;
                 us->fflags |= US_FL_BAD_SENSE;
             }
             goto Handle_Errors;
         }
 
         /*
          * Some devices claim to support larger sense but fail when
          * trying to request it. When a transport failure happens
          * using US_FS_SANE_SENSE, we always retry with a standard
          * (small) sense request. This fixes some USB GSM modems
          */
         if (temp_result == USB_STOR_TRANSPORT_FAILED &&
                 sense_size != US_SENSE_SIZE) {
             usb_stor_dbg(us, "-- auto-sense failure, retry small sense\n");
             sense_size = US_SENSE_SIZE;
             us->fflags &= ~US_FL_SANE_SENSE;
             us->fflags |= US_FL_BAD_SENSE;
             goto Retry_Sense;
         }
 
         /* Other failures */
         if (temp_result != USB_STOR_TRANSPORT_GOOD) {
             usb_stor_dbg(us, "-- auto-sense failure\n");
 
             /*
              * we skip the reset if this happens to be a
              * multi-target device, since failure of an
              * auto-sense is perfectly valid
              */
             srb->result = DID_ERROR << 16;
             if (!(us->fflags & US_FL_SCM_MULT_TARG))
                 goto Handle_Errors;
             return;
         }
 
         /*
          * If the sense data returned is larger than 18-bytes then we
          * assume this device supports requesting more in the future.
          * The response code must be 70h through 73h inclusive.
          */
         if (srb->sense_buffer[7] > (US_SENSE_SIZE - 8) &&
             !(us->fflags & US_FL_SANE_SENSE) &&
             !(us->fflags & US_FL_BAD_SENSE) &&
             (srb->sense_buffer[0] & 0x7C) == 0x70) {
             usb_stor_dbg(us, "-- SANE_SENSE support enabled\n");
             us->fflags |= US_FL_SANE_SENSE;
 
             /*
              * Indicate to the user that we truncated their sense
              * because we didn't know it supported larger sense.
              */
             usb_stor_dbg(us, "-- Sense data truncated to %i from %i\n",
                      US_SENSE_SIZE,
                      srb->sense_buffer[7] + 8);
             srb->sense_buffer[7] = (US_SENSE_SIZE - 8);
         }
 
         scsi_normalize_sense(srb->sense_buffer, SCSI_SENSE_BUFFERSIZE,
                      &sshdr);
 
         usb_stor_dbg(us, "-- Result from auto-sense is %d\n",
                  temp_result);
         usb_stor_dbg(us, "-- code: 0x%x, key: 0x%x, ASC: 0x%x, ASCQ: 0x%x\n",
                  sshdr.response_code, sshdr.sense_key,
                  sshdr.asc, sshdr.ascq);
 #ifdef CONFIG_USB_STORAGE_DEBUG
         usb_stor_show_sense(us, sshdr.sense_key, sshdr.asc, sshdr.ascq);
 #endif
 
         /* set the result so the higher layers expect this data */
         srb->result = SAM_STAT_CHECK_CONDITION;
 
         scdd = scsi_sense_desc_find(srb->sense_buffer,
                         SCSI_SENSE_BUFFERSIZE, 4);
         fm_ili = (scdd ? scdd[3] : srb->sense_buffer[2]) & 0xA0;
 
         /*
          * We often get empty sense data.  This could indicate that
          * everything worked or that there was an unspecified
          * problem.  We have to decide which.
          */
         if (sshdr.sense_key == 0 && sshdr.asc == 0 && sshdr.ascq == 0 &&
             fm_ili == 0) {
             /*
              * If things are really okay, then let's show that.
              * Zero out the sense buffer so the higher layers
              * won't realize we did an unsolicited auto-sense.
              */
             if (result == USB_STOR_TRANSPORT_GOOD) {
                 srb->result = SAM_STAT_GOOD;
                 srb->sense_buffer[0] = 0x0;
             }
 
             /*
              * ATA-passthru commands use sense data to report
              * the command completion status, and often devices
              * return Check Condition status when nothing is
              * wrong.
              */
             else if (srb->cmnd[0] == ATA_16 ||
                     srb->cmnd[0] == ATA_12) {
                 /* leave the data alone */
             }
 
             /*
              * If there was a problem, report an unspecified
              * hardware error to prevent the higher layers from
              * entering an infinite retry loop.
              */
             else {
                 srb->result = DID_ERROR << 16;
                 if ((sshdr.response_code & 0x72) == 0x72)
                     srb->sense_buffer[1] = HARDWARE_ERROR;
                 else
                     srb->sense_buffer[2] = HARDWARE_ERROR;
             }
         }
     }
 
     /*
      * Some devices don't work or return incorrect data the first
      * time they get a READ(10) command, or for the first READ(10)
      * after a media change.  If the INITIAL_READ10 flag is set,
      * keep track of whether READ(10) commands succeed.  If the
      * previous one succeeded and this one failed, set the REDO_READ10
      * flag to force a retry.
      */
     if (unlikely((us->fflags & US_FL_INITIAL_READ10) &&
             srb->cmnd[0] == READ_10)) {
         if (srb->result == SAM_STAT_GOOD) {
             set_bit(US_FLIDX_READ10_WORKED, &us->dflags);
         } else if (test_bit(US_FLIDX_READ10_WORKED, &us->dflags)) {
             clear_bit(US_FLIDX_READ10_WORKED, &us->dflags);
             set_bit(US_FLIDX_REDO_READ10, &us->dflags);
         }
 
         /*
          * Next, if the REDO_READ10 flag is set, return a result
          * code that will cause the SCSI core to retry the READ(10)
          * command immediately.
          */
         if (test_bit(US_FLIDX_REDO_READ10, &us->dflags)) {
             clear_bit(US_FLIDX_REDO_READ10, &us->dflags);
             srb->result = DID_IMM_RETRY << 16;
             srb->sense_buffer[0] = 0;
         }
     }
 
     /* Did we transfer less than the minimum amount required? */
     if ((srb->result == SAM_STAT_GOOD || srb->sense_buffer[2] == 0) &&
             scsi_bufflen(srb) - scsi_get_resid(srb) < srb->underflow)
         srb->result = DID_ERROR << 16;
 
     last_sector_hacks(us, srb);
     return;
 
     /*
      * Error and abort processing: try to resynchronize with the device
      * by issuing a port reset.  If that fails, try a class-specific
      * device reset.
      */
   Handle_Errors:
 
     /*
      * Set the RESETTING bit, and clear the ABORTING bit so that
      * the reset may proceed.
      */
     scsi_lock(us_to_host(us));
     set_bit(US_FLIDX_RESETTING, &us->dflags);
     clear_bit(US_FLIDX_ABORTING, &us->dflags);
     scsi_unlock(us_to_host(us));
 
     /*
      * We must release the device lock because the pre_reset routine
      * will want to acquire it.
      */
     mutex_unlock(&us->dev_mutex);
     result = usb_stor_port_reset(us);
     mutex_lock(&us->dev_mutex);
 
     if (result < 0) {
         scsi_lock(us_to_host(us));
         usb_stor_report_device_reset(us);
         scsi_unlock(us_to_host(us));
         us->transport_reset(us);
     }
     clear_bit(US_FLIDX_RESETTING, &us->dflags);
     last_sector_hacks(us, srb);
 }
 
 /* Stop the current URB transfer */
 void usb_stor_stop_transport(struct us_data *us)
 {
     /*
      * If the state machine is blocked waiting for an URB,
      * let's wake it up.  The test_and_clear_bit() call
      * guarantees that if a URB has just been submitted,
      * it won't be cancelled more than once.
      */
     if (test_and_clear_bit(US_FLIDX_URB_ACTIVE, &us->dflags)) {
         usb_stor_dbg(us, "-- cancelling URB\n");
         usb_unlink_urb(us->current_urb);
     }
 
     /* If we are waiting for a scatter-gather operation, cancel it. */
     if (test_and_clear_bit(US_FLIDX_SG_ACTIVE, &us->dflags)) {
         usb_stor_dbg(us, "-- cancelling sg request\n");
         usb_sg_cancel(&us->current_sg);
     }
 }
 
 /*
  * Control/Bulk and Control/Bulk/Interrupt transport
  */
 
 int usb_stor_CB_transport(struct scsi_cmnd *srb, struct us_data *us)
 {
     unsigned int transfer_length = scsi_bufflen(srb);
     unsigned int pipe = 0;
     int result;
 
     /* COMMAND STAGE */
     /* let's send the command via the control pipe */
     /*
      * Command is sometime (f.e. after scsi_eh_prep_cmnd) on the stack.
      * Stack may be vmallocated.  So no DMA for us.  Make a copy.
      */
     memcpy(us->iobuf, srb->cmnd, srb->cmd_len);
     result = usb_stor_ctrl_transfer(us, us->send_ctrl_pipe,
                       US_CBI_ADSC, 
                       USB_TYPE_CLASS | USB_RECIP_INTERFACE, 0, 
                       us->ifnum, us->iobuf, srb->cmd_len);
 
     /* check the return code for the command */
     usb_stor_dbg(us, "Call to usb_stor_ctrl_transfer() returned %d\n",
              result);
 
     /* if we stalled the command, it means command failed */
     if (result == USB_STOR_XFER_STALLED) {
         return USB_STOR_TRANSPORT_FAILED;
     }
 
     /* Uh oh... serious problem here */
     if (result != USB_STOR_XFER_GOOD) {
         return USB_STOR_TRANSPORT_ERROR;
     }
 
     /* DATA STAGE */
     /* transfer the data payload for this command, if one exists*/
     if (transfer_length) {
         pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? 
                 us->recv_bulk_pipe : us->send_bulk_pipe;
         result = usb_stor_bulk_srb(us, pipe, srb);
         usb_stor_dbg(us, "CBI data stage result is 0x%x\n", result);
 
         /* if we stalled the data transfer it means command failed */
         if (result == USB_STOR_XFER_STALLED)
             return USB_STOR_TRANSPORT_FAILED;
         if (result > USB_STOR_XFER_STALLED)
             return USB_STOR_TRANSPORT_ERROR;
     }
 
     /* STATUS STAGE */
 
     /*
      * NOTE: CB does not have a status stage.  Silly, I know.  So
      * we have to catch this at a higher level.
      */
     if (us->protocol != USB_PR_CBI)
         return USB_STOR_TRANSPORT_GOOD;
 
     result = usb_stor_intr_transfer(us, us->iobuf, 2);
     usb_stor_dbg(us, "Got interrupt data (0x%x, 0x%x)\n",
              us->iobuf[0], us->iobuf[1]);
     if (result != USB_STOR_XFER_GOOD)
         return USB_STOR_TRANSPORT_ERROR;
 
     /*
      * UFI gives us ASC and ASCQ, like a request sense
      *
      * REQUEST_SENSE and INQUIRY don't affect the sense data on UFI
      * devices, so we ignore the information for those commands.  Note
      * that this means we could be ignoring a real error on these
      * commands, but that can't be helped.
      */
     if (us->subclass == USB_SC_UFI) {
         if (srb->cmnd[0] == REQUEST_SENSE ||
             srb->cmnd[0] == INQUIRY)
             return USB_STOR_TRANSPORT_GOOD;
         if (us->iobuf[0])
             goto Failed;
         return USB_STOR_TRANSPORT_GOOD;
     }
 
     /*
      * If not UFI, we interpret the data as a result code 
      * The first byte should always be a 0x0.
      *
      * Some bogus devices don't follow that rule.  They stuff the ASC
      * into the first byte -- so if it's non-zero, call it a failure.
      */
     if (us->iobuf[0]) {
         usb_stor_dbg(us, "CBI IRQ data showed reserved bType 0x%x\n",
                  us->iobuf[0]);
         goto Failed;
 
     }
 
     /* The second byte & 0x0F should be 0x0 for good, otherwise error */
     switch (us->iobuf[1] & 0x0F) {
         case 0x00: 
             return USB_STOR_TRANSPORT_GOOD;
         case 0x01: 
             goto Failed;
     }
     return USB_STOR_TRANSPORT_ERROR;
 
     /*
      * the CBI spec requires that the bulk pipe must be cleared
      * following any data-in/out command failure (section 2.4.3.1.3)
      */
   Failed:
     if (pipe)
         usb_stor_clear_halt(us, pipe);
     return USB_STOR_TRANSPORT_FAILED;
 }
 EXPORT_SYMBOL_GPL(usb_stor_CB_transport);
 
 /*
  * Bulk only transport
  */
 
 /* Determine what the maximum LUN supported is */
 int usb_stor_Bulk_max_lun(struct us_data *us)
 {
     int result;
 
     /* issue the command */
     us->iobuf[0] = 0;
     result = usb_stor_control_msg(us, us->recv_ctrl_pipe,
                  US_BULK_GET_MAX_LUN, 
                  USB_DIR_IN | USB_TYPE_CLASS | 
                  USB_RECIP_INTERFACE,
                  0, us->ifnum, us->iobuf, 1, 10*HZ);
 
     usb_stor_dbg(us, "GetMaxLUN command result is %d, data is %d\n",
              result, us->iobuf[0]);
 
     /*
      * If we have a successful request, return the result if valid. The
      * CBW LUN field is 4 bits wide, so the value reported by the device
      * should fit into that.
      */
     if (result > 0) {
         if (us->iobuf[0] < 16) {
             return us->iobuf[0];
         } else {
             dev_info(&us->pusb_intf->dev,
                  "Max LUN %d is not valid, using 0 instead",
                  us->iobuf[0]);
         }
     }
 
     /*
      * Some devices don't like GetMaxLUN.  They may STALL the control
      * pipe, they may return a zero-length result, they may do nothing at
      * all and timeout, or they may fail in even more bizarrely creative
      * ways.  In these cases the best approach is to use the default
      * value: only one LUN.
      */
     return 0;
 }
 
 int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
 {
     struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf;
     struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf;
     unsigned int transfer_length = scsi_bufflen(srb);
     unsigned int residue;
     int result;
     int fake_sense = 0;
     unsigned int cswlen;
     unsigned int cbwlen = US_BULK_CB_WRAP_LEN;
 
     /* Take care of BULK32 devices; set extra byte to 0 */
     if (unlikely(us->fflags & US_FL_BULK32)) {
         cbwlen = 32;
         us->iobuf[31] = 0;
     }
 
     /* set up the command wrapper */
     bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
     bcb->DataTransferLength = cpu_to_le32(transfer_length);
     bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ?
         US_BULK_FLAG_IN : 0;
     bcb->Tag = ++us->tag;
     bcb->Lun = srb->device->lun;
     if (us->fflags & US_FL_SCM_MULT_TARG)
         bcb->Lun |= srb->device->id << 4;
     bcb->Length = srb->cmd_len;
 
     /* copy the command payload */
     memset(bcb->CDB, 0, sizeof(bcb->CDB));
     memcpy(bcb->CDB, srb->cmnd, bcb->Length);
 
     /* send it to out endpoint */
     usb_stor_dbg(us, "Bulk Command S 0x%x T 0x%x L %d F %d Trg %d LUN %d CL %d\n",
              le32_to_cpu(bcb->Signature), bcb->Tag,
              le32_to_cpu(bcb->DataTransferLength), bcb->Flags,
              (bcb->Lun >> 4), (bcb->Lun & 0x0F),
              bcb->Length);
     result = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
                 bcb, cbwlen, NULL);
     usb_stor_dbg(us, "Bulk command transfer result=%d\n", result);
     if (result != USB_STOR_XFER_GOOD)
         return USB_STOR_TRANSPORT_ERROR;
 
     /* DATA STAGE */
     /* send/receive data payload, if there is any */
 
     /*
      * Some USB-IDE converter chips need a 100us delay between the
      * command phase and the data phase.  Some devices need a little
      * more than that, probably because of clock rate inaccuracies.
      */
     if (unlikely(us->fflags & US_FL_GO_SLOW))
         usleep_range(125, 150);
 
     if (transfer_length) {
         unsigned int pipe = srb->sc_data_direction == DMA_FROM_DEVICE ? 
                 us->recv_bulk_pipe : us->send_bulk_pipe;
         result = usb_stor_bulk_srb(us, pipe, srb);
         usb_stor_dbg(us, "Bulk data transfer result 0x%x\n", result);
         if (result == USB_STOR_XFER_ERROR)
             return USB_STOR_TRANSPORT_ERROR;
 
         /*
          * If the device tried to send back more data than the
          * amount requested, the spec requires us to transfer
          * the CSW anyway.  Since there's no point retrying
          * the command, we'll return fake sense data indicating
          * Illegal Request, Invalid Field in CDB.
          */
         if (result == USB_STOR_XFER_LONG)
             fake_sense = 1;
 
         /*
          * Sometimes a device will mistakenly skip the data phase
          * and go directly to the status phase without sending a
          * zero-length packet.  If we get a 13-byte response here,
          * check whether it really is a CSW.
          */
         if (result == USB_STOR_XFER_SHORT &&
                 srb->sc_data_direction == DMA_FROM_DEVICE &&
                 transfer_length - scsi_get_resid(srb) ==
                     US_BULK_CS_WRAP_LEN) {
             struct scatterlist *sg = NULL;
             unsigned int offset = 0;
 
             if (usb_stor_access_xfer_buf((unsigned char *) bcs,
                     US_BULK_CS_WRAP_LEN, srb, &sg,
                     &offset, FROM_XFER_BUF) ==
                         US_BULK_CS_WRAP_LEN &&
                     bcs->Signature ==
                         cpu_to_le32(US_BULK_CS_SIGN)) {
                 usb_stor_dbg(us, "Device skipped data phase\n");
                 scsi_set_resid(srb, transfer_length);
                 goto skipped_data_phase;
             }
         }
     }
 
     /*
      * See flow chart on pg 15 of the Bulk Only Transport spec for
      * an explanation of how this code works.
      */
 
     /* get CSW for device status */
     usb_stor_dbg(us, "Attempting to get CSW...\n");
     result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
                 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
 
     /*
      * Some broken devices add unnecessary zero-length packets to the
      * end of their data transfers.  Such packets show up as 0-length
      * CSWs.  If we encounter such a thing, try to read the CSW again.
      */
     if (result == USB_STOR_XFER_SHORT && cswlen == 0) {
         usb_stor_dbg(us, "Received 0-length CSW; retrying...\n");
         result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
                 bcs, US_BULK_CS_WRAP_LEN, &cswlen);
     }
 
     /* did the attempt to read the CSW fail? */
     if (result == USB_STOR_XFER_STALLED) {
 
         /* get the status again */
         usb_stor_dbg(us, "Attempting to get CSW (2nd try)...\n");
         result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
                 bcs, US_BULK_CS_WRAP_LEN, NULL);
     }
 
     /* if we still have a failure at this point, we're in trouble */
     usb_stor_dbg(us, "Bulk status result = %d\n", result);
     if (result != USB_STOR_XFER_GOOD)
         return USB_STOR_TRANSPORT_ERROR;
 
  skipped_data_phase:
     /* check bulk status */
     residue = le32_to_cpu(bcs->Residue);
     usb_stor_dbg(us, "Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n",
              le32_to_cpu(bcs->Signature), bcs->Tag,
              residue, bcs->Status);
     if (!(bcs->Tag == us->tag || (us->fflags & US_FL_BULK_IGNORE_TAG)) ||
         bcs->Status > US_BULK_STAT_PHASE) {
         usb_stor_dbg(us, "Bulk logical error\n");
         return USB_STOR_TRANSPORT_ERROR;
     }
 
     /*
      * Some broken devices report odd signatures, so we do not check them
      * for validity against the spec. We store the first one we see,
      * and check subsequent transfers for validity against this signature.
      */
     if (!us->bcs_signature) {
         us->bcs_signature = bcs->Signature;
         if (us->bcs_signature != cpu_to_le32(US_BULK_CS_SIGN))
             usb_stor_dbg(us, "Learnt BCS signature 0x%08X\n",
                      le32_to_cpu(us->bcs_signature));
     } else if (bcs->Signature != us->bcs_signature) {
         usb_stor_dbg(us, "Signature mismatch: got %08X, expecting %08X\n",
                  le32_to_cpu(bcs->Signature),
                  le32_to_cpu(us->bcs_signature));
         return USB_STOR_TRANSPORT_ERROR;
     }
 
     /*
      * try to compute the actual residue, based on how much data
      * was really transferred and what the device tells us
      */
     if (residue && !(us->fflags & US_FL_IGNORE_RESIDUE)) {
 
         /*
          * Heuristically detect devices that generate bogus residues
          * by seeing what happens with INQUIRY and READ CAPACITY
          * commands.
          */
         if (bcs->Status == US_BULK_STAT_OK &&
                 scsi_get_resid(srb) == 0 &&
                     ((srb->cmnd[0] == INQUIRY &&
                         transfer_length == 36) ||
                     (srb->cmnd[0] == READ_CAPACITY &&
                         transfer_length == 8))) {
             us->fflags |= US_FL_IGNORE_RESIDUE;
 
         } else {
             residue = min(residue, transfer_length);
             scsi_set_resid(srb, max(scsi_get_resid(srb), residue));
         }
     }
 
     /* based on the status code, we report good or bad */
     switch (bcs->Status) {
         case US_BULK_STAT_OK:
             /* device babbled -- return fake sense data */
             if (fake_sense) {
                 memcpy(srb->sense_buffer, 
                        usb_stor_sense_invalidCDB, 
                        sizeof(usb_stor_sense_invalidCDB));
                 return USB_STOR_TRANSPORT_NO_SENSE;
             }
 
             /* command good -- note that data could be short */
             return USB_STOR_TRANSPORT_GOOD;
 
         case US_BULK_STAT_FAIL:
             /* command failed */
             return USB_STOR_TRANSPORT_FAILED;
 
         case US_BULK_STAT_PHASE:
             /*
              * phase error -- note that a transport reset will be
              * invoked by the invoke_transport() function
              */
             return USB_STOR_TRANSPORT_ERROR;
     }
 
     /* we should never get here, but if we do, we're in trouble */
     return USB_STOR_TRANSPORT_ERROR;
 }
 EXPORT_SYMBOL_GPL(usb_stor_Bulk_transport);
 
 /***********************************************************************
  * Reset routines
  ***********************************************************************/
 
 /*
  * This is the common part of the device reset code.
  *
  * It's handy that every transport mechanism uses the control endpoint for
  * resets.
  *
  * Basically, we send a reset with a 5-second timeout, so we don't get
  * jammed attempting to do the reset.
  */
 static int usb_stor_reset_common(struct us_data *us,
         u8 request, u8 requesttype,
         u16 value, u16 index, void *data, u16 size)
 {
     int result;
     int result2;
 
     if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
         usb_stor_dbg(us, "No reset during disconnect\n");
         return -EIO;
     }
 
     result = usb_stor_control_msg(us, us->send_ctrl_pipe,
             request, requesttype, value, index, data, size,
             5*HZ);
     if (result < 0) {
         usb_stor_dbg(us, "Soft reset failed: %d\n", result);
         return result;
     }
 
     /*
      * Give the device some time to recover from the reset,
      * but don't delay disconnect processing.
      */
     wait_event_interruptible_timeout(us->delay_wait,
             test_bit(US_FLIDX_DISCONNECTING, &us->dflags),
             HZ*6);
     if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
         usb_stor_dbg(us, "Reset interrupted by disconnect\n");
         return -EIO;
     }
 
     usb_stor_dbg(us, "Soft reset: clearing bulk-in endpoint halt\n");
     result = usb_stor_clear_halt(us, us->recv_bulk_pipe);
 
     usb_stor_dbg(us, "Soft reset: clearing bulk-out endpoint halt\n");
     result2 = usb_stor_clear_halt(us, us->send_bulk_pipe);
 
     /* return a result code based on the result of the clear-halts */
     if (result >= 0)
         result = result2;
     if (result < 0)
         usb_stor_dbg(us, "Soft reset failed\n");
     else
         usb_stor_dbg(us, "Soft reset done\n");
     return result;
 }
 
 /* This issues a CB[I] Reset to the device in question */
 #define CB_RESET_CMD_SIZE   12
 
 int usb_stor_CB_reset(struct us_data *us)
 {
     memset(us->iobuf, 0xFF, CB_RESET_CMD_SIZE);
     us->iobuf[0] = SEND_DIAGNOSTIC;
     us->iobuf[1] = 4;
     return usb_stor_reset_common(us, US_CBI_ADSC, 
                  USB_TYPE_CLASS | USB_RECIP_INTERFACE,
                  0, us->ifnum, us->iobuf, CB_RESET_CMD_SIZE);
 }
 EXPORT_SYMBOL_GPL(usb_stor_CB_reset);
 
 /*
  * This issues a Bulk-only Reset to the device in question, including
  * clearing the subsequent endpoint halts that may occur.
  */
 int usb_stor_Bulk_reset(struct us_data *us)
 {
     return usb_stor_reset_common(us, US_BULK_RESET_REQUEST, 
                  USB_TYPE_CLASS | USB_RECIP_INTERFACE,
                  0, us->ifnum, NULL, 0);
 }
 EXPORT_SYMBOL_GPL(usb_stor_Bulk_reset);
 
 /*
  * Issue a USB port reset to the device.  The caller must not hold
  * us->dev_mutex.
  */
 int usb_stor_port_reset(struct us_data *us)
 {
     int result;
 
     /*for these devices we must use the class specific method */
     if (us->pusb_dev->quirks & USB_QUIRK_RESET)
         return -EPERM;
 
     result = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
     if (result < 0)
         usb_stor_dbg(us, "unable to lock device for reset: %d\n",
                  result);
     else {
         /* Were we disconnected while waiting for the lock? */
         if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
             result = -EIO;
             usb_stor_dbg(us, "No reset during disconnect\n");
         } else {
             result = usb_reset_device(us->pusb_dev);
             usb_stor_dbg(us, "usb_reset_device returns %d\n",
                      result);
         }
         usb_unlock_device(us->pusb_dev);
     }
     return result;
 }

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