2 files changed, 78 insertions, 1 deletions

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index 71514be8b71..181f78c8410 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -74,6 +74,7 @@ struct dev_state {
         void __user *disccontext;
         unsigned long ifclaimed;
         u32 secid;
+        u32 disabled_bulk_eps;
 };
 
 struct async {
@@ -88,6 +89,8 @@ struct async {
         struct urb *urb;
         int status;
         u32 secid;
+        u8 bulk_addr;
+        u8 bulk_status;
 };
 
 static int usbfs_snoop;
@@ -343,6 +346,43 @@ static void snoop_urb(struct usb_device *udev,
         }
 }
 
+#define AS_CONTINUATION 1
+#define AS_UNLINK       2
+
+static void cancel_bulk_urbs(struct dev_state *ps, unsigned bulk_addr)
+__releases(ps->lock)
+__acquires(ps->lock)
+{
+        struct async *as;
+
+        /* Mark all the pending URBs that match bulk_addr, up to but not
+         * including the first one without AS_CONTINUATION.  If such an
+         * URB is encountered then a new transfer has already started so
+         * the endpoint doesn't need to be disabled; otherwise it does.
+         */
+        list_for_each_entry(as, &ps->async_pending, asynclist) {
+                if (as->bulk_addr == bulk_addr) {
+                        if (as->bulk_status != AS_CONTINUATION)
+                                goto rescan;
+                        as->bulk_status = AS_UNLINK;
+                        as->bulk_addr = 0;
+                }
+        }
+        ps->disabled_bulk_eps |= (1 << bulk_addr);
+
+        /* Now carefully unlink all the marked pending URBs */
+ rescan:
+        list_for_each_entry(as, &ps->async_pending, asynclist) {
+                if (as->bulk_status == AS_UNLINK) {
+                        as->bulk_status = 0;            /* Only once */
+                        spin_unlock(&ps->lock);         /* Allow completions */
+                        usb_unlink_urb(as->urb);
+                        spin_lock(&ps->lock);
+                        goto rescan;
+                }
+        }
+}
+
 static void async_completed(struct urb *urb)
 {
         struct async *as = urb->context;
@@ -371,6 +411,9 @@ static void async_completed(struct urb *urb)
         snoop(&urb->dev->dev, "urb complete\n");
         snoop_urb(urb->dev, as->userurb, urb->pipe, urb->actual_length,
                         as->status, COMPLETE);
+        if (as->status < 0 && as->bulk_addr && as->status != -ECONNRESET &&
+                        as->status != -ENOENT)
+                cancel_bulk_urbs(ps, as->bulk_addr);
         spin_unlock(&ps->lock);
 
         if (signr)
@@ -993,6 +1036,7 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb,
 
         if (uurb->flags & ~(USBDEVFS_URB_ISO_ASAP |
                                 USBDEVFS_URB_SHORT_NOT_OK |
+                                USBDEVFS_URB_BULK_CONTINUATION |
                                 USBDEVFS_URB_NO_FSBR |
                                 USBDEVFS_URB_ZERO_PACKET |
                                 USBDEVFS_URB_NO_INTERRUPT))
@@ -1194,7 +1238,39 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb,
         snoop_urb(ps->dev, as->userurb, as->urb->pipe,
                         as->urb->transfer_buffer_length, 0, SUBMIT);
         async_newpending(as);
-        if ((ret = usb_submit_urb(as->urb, GFP_KERNEL))) {
+
+        if (usb_endpoint_xfer_bulk(&ep->desc)) {
+                spin_lock_irq(&ps->lock);
+
+                /* Not exactly the endpoint address; the direction bit is
+                 * shifted to the 0x10 position so that the value will be
+                 * between 0 and 31.
+                 */
+                as->bulk_addr = usb_endpoint_num(&ep->desc) |
+                        ((ep->desc.bEndpointAddress & USB_ENDPOINT_DIR_MASK)
+                                >> 3);
+
+                /* If this bulk URB is the start of a new transfer, re-enable
+                 * the endpoint.  Otherwise mark it as a continuation URB.
+                 */
+                if (uurb->flags & USBDEVFS_URB_BULK_CONTINUATION)
+                        as->bulk_status = AS_CONTINUATION;
+                else
+                        ps->disabled_bulk_eps &= ~(1 << as->bulk_addr);
+
+                /* Don't accept continuation URBs if the endpoint is
+                 * disabled because of an earlier error.
+                 */
+                if (ps->disabled_bulk_eps & (1 << as->bulk_addr))
+                        ret = -EREMOTEIO;
+                else
+                        ret = usb_submit_urb(as->urb, GFP_ATOMIC);
+                spin_unlock_irq(&ps->lock);
+        } else {
+                ret = usb_submit_urb(as->urb, GFP_KERNEL);
+        }
+
+        if (ret) {
                 dev_printk(KERN_DEBUG, &ps->dev->dev,
                            "usbfs: usb_submit_urb returned %d\n", ret);
                 snoop_urb(ps->dev, as->userurb, as->urb->pipe,
diff --git a/include/linux/usbdevice_fs.h b/include/linux/usbdevice_fs.h
index 00ceebeb9e5..b2a7d8ba6ee 100644
--- a/include/linux/usbdevice_fs.h
+++ b/include/linux/usbdevice_fs.h
@@ -77,6 +77,7 @@ struct usbdevfs_connectinfo {
 
 #define USBDEVFS_URB_SHORT_NOT_OK       0x01
 #define USBDEVFS_URB_ISO_ASAP           0x02
+#define USBDEVFS_URB_BULK_CONTINUATION  0x04
 #define USBDEVFS_URB_NO_FSBR            0x20
 #define USBDEVFS_URB_ZERO_PACKET        0x40
 #define USBDEVFS_URB_NO_INTERRUPT       0x80