1 files changed, 36 insertions, 41 deletions

diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index 6b14f8d253f1..6bfd99dd57aa 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -320,16 +320,17 @@ static int usb_stor_control_thread(void * __us)
                 /* lock the device pointers */
                 mutex_lock(&(us->dev_mutex));
 
-                /* if the device has disconnected, we are free to exit */
-                if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
-                        US_DEBUGP("-- exiting\n");
+                /* lock access to the state */
+                scsi_lock(host);
+
+                /* When we are called with no command pending, we're done */
+                if (us->srb == NULL) {
+                        scsi_unlock(host);
                         mutex_unlock(&us->dev_mutex);
+                        US_DEBUGP("-- exiting\n");
                         break;
                 }
 
-                /* lock access to the state */
-                scsi_lock(host);
-
                 /* has the command timed out *already* ? */
                 if (test_bit(US_FLIDX_TIMED_OUT, &us->dflags)) {
                         us->srb->result = DID_ABORT << 16;
@@ -384,12 +385,8 @@ static int usb_stor_control_thread(void * __us)
                 /* lock access to the state */
                 scsi_lock(host);
 
-                /* did the command already complete because of a disconnect? */
-                if (!us->srb)
-                        ;               /* nothing to do */
-
                 /* indicate that the command is done */
-                else if (us->srb->result != DID_ABORT << 16) {
+                if (us->srb->result != DID_ABORT << 16) {
                         US_DEBUGP("scsi cmd done, result=0x%x\n", 
                                    us->srb->result);
                         us->srb->scsi_done(us->srb);
@@ -820,11 +817,10 @@ static void usb_stor_release_resources(struct us_data *us)
         US_DEBUGP("-- %s\n", __func__);
 
         /* Tell the control thread to exit.  The SCSI host must
-         * already have been removed so it won't try to queue
-         * any more commands.
+         * already have been removed and the DISCONNECTING flag set
+         * so that we won't accept any more commands.
          */
         US_DEBUGP("-- sending exit command to thread\n");
-        set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
         complete(&us->cmnd_ready);
         if (us->ctl_thread)
                 kthread_stop(us->ctl_thread);
@@ -859,39 +855,36 @@ static void dissociate_dev(struct us_data *us)
         usb_set_intfdata(us->pusb_intf, NULL);
 }
 
-/* First stage of disconnect processing: stop all commands and remove
- * the host */
+/* First stage of disconnect processing: stop SCSI scanning,
+ * remove the host, and stop accepting new commands
+ */
 static void quiesce_and_remove_host(struct us_data *us)
 {
         struct Scsi_Host *host = us_to_host(us);
 
-        /* Prevent new USB transfers, stop the current command, and
-         * interrupt a SCSI-scan or device-reset delay */
-        scsi_lock(host);
-        set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
-        scsi_unlock(host);
-        usb_stor_stop_transport(us);
-        wake_up(&us->delay_wait);
+        /* If the device is really gone, cut short reset delays */
+        if (us->pusb_dev->state == USB_STATE_NOTATTACHED)
+                set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
 
-        /* queuecommand won't accept any new commands and the control
-         * thread won't execute a previously-queued command.  If there
-         * is such a command pending, complete it with an error. */
-        mutex_lock(&us->dev_mutex);
-        if (us->srb) {
-                us->srb->result = DID_NO_CONNECT << 16;
-                scsi_lock(host);
-                us->srb->scsi_done(us->srb);
-                us->srb = NULL;
-                complete(&us->notify);          /* in case of an abort */
-                scsi_unlock(host);
-        }
-        mutex_unlock(&us->dev_mutex);
+        /* Prevent SCSI-scanning (if it hasn't started yet)
+         * and wait for the SCSI-scanning thread to stop.
+         */
+        set_bit(US_FLIDX_DONT_SCAN, &us->dflags);
+        wake_up(&us->delay_wait);
+        wait_for_completion(&us->scanning_done);
 
-        /* Now we own no commands so it's safe to remove the SCSI host */
+        /* Removing the host will perform an orderly shutdown: caches
+         * synchronized, disks spun down, etc.
+         */
         scsi_remove_host(host);
 
-        /* Wait for the SCSI-scanning thread to stop */
-        wait_for_completion(&us->scanning_done);
+        /* Prevent any new commands from being accepted and cut short
+         * reset delays.
+         */
+        scsi_lock(host);
+        set_bit(US_FLIDX_DISCONNECTING, &us->dflags);
+        scsi_unlock(host);
+        wake_up(&us->delay_wait);
 }
 
 /* Second stage of disconnect processing: deallocate all resources */
@@ -919,12 +912,12 @@ static int usb_stor_scan_thread(void * __us)
                 printk(KERN_DEBUG "usb-storage: waiting for device "
                                 "to settle before scanning\n");
                 wait_event_freezable_timeout(us->delay_wait,
-                                test_bit(US_FLIDX_DISCONNECTING, &us->dflags),
+                                test_bit(US_FLIDX_DONT_SCAN, &us->dflags),
                                 delay_use * HZ);
         }
 
         /* If the device is still connected, perform the scanning */
-        if (!test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
+        if (!test_bit(US_FLIDX_DONT_SCAN, &us->dflags)) {
 
                 /* For bulk-only devices, determine the max LUN value */
                 if (us->protocol == US_PR_BULK &&
@@ -1023,6 +1016,7 @@ static int storage_probe(struct usb_interface *intf,
         if (IS_ERR(th)) {
                 printk(KERN_WARNING USB_STORAGE 
                        "Unable to start the device-scanning thread\n");
+                complete(&us->scanning_done);
                 quiesce_and_remove_host(us);
                 result = PTR_ERR(th);
                 goto BadDevice;
@@ -1065,6 +1059,7 @@ static struct usb_driver usb_storage_driver = {
         .pre_reset =    storage_pre_reset,
         .post_reset =   storage_post_reset,
         .id_table =     storage_usb_ids,
+        .soft_unbind =  1,
 };
 
 static int __init usb_stor_init(void)