[PATCH] USB Storage: port reset on transport error
This patch causes a port reset whenever there's a transport error or abort.
If that fails it reverts back to doing a mass-storage device reset. It
started life as as497 and was rediffed by me.
This makes error recovery a lot quicker and more reliable.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
index 419afb2..e6b1c6c 100644
--- a/drivers/usb/storage/transport.c
+++ b/drivers/usb/storage/transport.c
@@ -541,15 +541,15 @@
*/
if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
US_DEBUGP("-- command was aborted\n");
- goto Handle_Abort;
+ 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) {
US_DEBUGP("-- transport indicates error, resetting\n");
- us->transport_reset(us);
srb->result = DID_ERROR << 16;
- return;
+ goto Handle_Errors;
}
/* if the transport provided its own sense data, don't auto-sense */
@@ -669,7 +669,8 @@
if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
US_DEBUGP("-- auto-sense aborted\n");
- goto Handle_Abort;
+ srb->result = DID_ABORT << 16;
+ goto Handle_Errors;
}
if (temp_result != USB_STOR_TRANSPORT_GOOD) {
US_DEBUGP("-- auto-sense failure\n");
@@ -678,9 +679,9 @@
* multi-target device, since failure of an
* auto-sense is perfectly valid
*/
- if (!(us->flags & US_FL_SCM_MULT_TARG))
- us->transport_reset(us);
srb->result = DID_ERROR << 16;
+ if (!(us->flags & US_FL_SCM_MULT_TARG))
+ goto Handle_Errors;
return;
}
@@ -721,12 +722,28 @@
return;
- /* abort processing: the bulk-only transport requires a reset
- * following an abort */
- Handle_Abort:
- srb->result = DID_ABORT << 16;
- if (us->protocol == US_PR_BULK)
+ /* 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:
+
+ /* Let the SCSI layer know we are doing a reset, set the
+ * RESETTING bit, and clear the ABORTING bit so that the reset
+ * may proceed. */
+ scsi_lock(us_to_host(us));
+ usb_stor_report_bus_reset(us);
+ set_bit(US_FLIDX_RESETTING, &us->flags);
+ clear_bit(US_FLIDX_ABORTING, &us->flags);
+ scsi_unlock(us_to_host(us));
+
+ result = usb_stor_port_reset(us);
+ 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->flags);
}
/* Stop the current URB transfer */
@@ -1134,24 +1151,18 @@
{
int result;
int result2;
- int rc = FAILED;
- /* Let the SCSI layer know we are doing a reset, set the
- * RESETTING bit, and clear the ABORTING bit so that the reset
- * may proceed.
- */
- scsi_lock(us_to_host(us));
- usb_stor_report_device_reset(us);
- set_bit(US_FLIDX_RESETTING, &us->flags);
- clear_bit(US_FLIDX_ABORTING, &us->flags);
- scsi_unlock(us_to_host(us));
+ if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+ US_DEBUGP("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) {
US_DEBUGP("Soft reset failed: %d\n", result);
- goto Done;
+ return result;
}
/* Give the device some time to recover from the reset,
@@ -1161,7 +1172,7 @@
HZ*6);
if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
US_DEBUGP("Reset interrupted by disconnect\n");
- goto Done;
+ return -EIO;
}
US_DEBUGP("Soft reset: clearing bulk-in endpoint halt\n");
@@ -1173,16 +1184,11 @@
/* return a result code based on the result of the clear-halts */
if (result >= 0)
result = result2;
- if (result < 0) {
+ if (result < 0)
US_DEBUGP("Soft reset failed\n");
- goto Done;
- }
- US_DEBUGP("Soft reset done\n");
- rc = SUCCESS;
-
- Done:
- clear_bit(US_FLIDX_RESETTING, &us->flags);
- return rc;
+ else
+ US_DEBUGP("Soft reset done\n");
+ return result;
}
/* This issues a CB[I] Reset to the device in question
@@ -1212,3 +1218,32 @@
USB_TYPE_CLASS | USB_RECIP_INTERFACE,
0, us->ifnum, NULL, 0);
}
+
+/* Issue a USB port reset to the device. But don't do anything if
+ * there's more than one interface in the device, so that other users
+ * are not affected. */
+int usb_stor_port_reset(struct us_data *us)
+{
+ int result, rc;
+
+ if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+ result = -EIO;
+ US_DEBUGP("No reset during disconnect\n");
+ } else if (us->pusb_dev->actconfig->desc.bNumInterfaces != 1) {
+ result = -EBUSY;
+ US_DEBUGP("Refusing to reset a multi-interface device\n");
+ } else {
+ result = rc =
+ usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
+ if (result < 0) {
+ US_DEBUGP("unable to lock device for reset: %d\n",
+ result);
+ } else {
+ result = usb_reset_device(us->pusb_dev);
+ if (rc)
+ usb_unlock_device(us->pusb_dev);
+ US_DEBUGP("usb_reset_device returns %d\n", result);
+ }
+ }
+ return result;
+}