diff options
| -rw-r--r-- | drivers/usb/core/urb.c | 89 |
1 files changed, 54 insertions, 35 deletions
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c index 7bc23469f4e4..27e83e55a590 100644 --- a/drivers/usb/core/urb.c +++ b/drivers/usb/core/urb.c @@ -772,11 +772,12 @@ void usb_block_urb(struct urb *urb) EXPORT_SYMBOL_GPL(usb_block_urb); /** - * usb_kill_anchored_urbs - cancel transfer requests en masse + * usb_kill_anchored_urbs - kill all URBs associated with an anchor * @anchor: anchor the requests are bound to * - * this allows all outstanding URBs to be killed starting - * from the back of the queue + * This kills all outstanding URBs starting from the back of the queue, + * with guarantee that no completer callbacks will take place from the + * anchor after this function returns. * * This routine should not be called by a driver after its disconnect * method has returned. @@ -784,20 +785,26 @@ EXPORT_SYMBOL_GPL(usb_block_urb); void usb_kill_anchored_urbs(struct usb_anchor *anchor) { struct urb *victim; + int surely_empty; - spin_lock_irq(&anchor->lock); - while (!list_empty(&anchor->urb_list)) { - victim = list_entry(anchor->urb_list.prev, struct urb, - anchor_list); - /* we must make sure the URB isn't freed before we kill it*/ - usb_get_urb(victim); - spin_unlock_irq(&anchor->lock); - /* this will unanchor the URB */ - usb_kill_urb(victim); - usb_put_urb(victim); + do { spin_lock_irq(&anchor->lock); - } - spin_unlock_irq(&anchor->lock); + while (!list_empty(&anchor->urb_list)) { + victim = list_entry(anchor->urb_list.prev, + struct urb, anchor_list); + /* make sure the URB isn't freed before we kill it */ + usb_get_urb(victim); + spin_unlock_irq(&anchor->lock); + /* this will unanchor the URB */ + usb_kill_urb(victim); + usb_put_urb(victim); + spin_lock_irq(&anchor->lock); + } + surely_empty = usb_anchor_check_wakeup(anchor); + + spin_unlock_irq(&anchor->lock); + cpu_relax(); + } while (!surely_empty); } EXPORT_SYMBOL_GPL(usb_kill_anchored_urbs); @@ -816,21 +823,27 @@ EXPORT_SYMBOL_GPL(usb_kill_anchored_urbs); void usb_poison_anchored_urbs(struct usb_anchor *anchor) { struct urb *victim; + int surely_empty; - spin_lock_irq(&anchor->lock); - anchor->poisoned = 1; - while (!list_empty(&anchor->urb_list)) { - victim = list_entry(anchor->urb_list.prev, struct urb, - anchor_list); - /* we must make sure the URB isn't freed before we kill it*/ - usb_get_urb(victim); - spin_unlock_irq(&anchor->lock); - /* this will unanchor the URB */ - usb_poison_urb(victim); - usb_put_urb(victim); + do { spin_lock_irq(&anchor->lock); - } - spin_unlock_irq(&anchor->lock); + anchor->poisoned = 1; + while (!list_empty(&anchor->urb_list)) { + victim = list_entry(anchor->urb_list.prev, + struct urb, anchor_list); + /* make sure the URB isn't freed before we kill it */ + usb_get_urb(victim); + spin_unlock_irq(&anchor->lock); + /* this will unanchor the URB */ + usb_poison_urb(victim); + usb_put_urb(victim); + spin_lock_irq(&anchor->lock); + } + surely_empty = usb_anchor_check_wakeup(anchor); + + spin_unlock_irq(&anchor->lock); + cpu_relax(); + } while (!surely_empty); } EXPORT_SYMBOL_GPL(usb_poison_anchored_urbs); @@ -970,14 +983,20 @@ void usb_scuttle_anchored_urbs(struct usb_anchor *anchor) { struct urb *victim; unsigned long flags; + int surely_empty; + + do { + spin_lock_irqsave(&anchor->lock, flags); + while (!list_empty(&anchor->urb_list)) { + victim = list_entry(anchor->urb_list.prev, + struct urb, anchor_list); + __usb_unanchor_urb(victim, anchor); + } + surely_empty = usb_anchor_check_wakeup(anchor); - spin_lock_irqsave(&anchor->lock, flags); - while (!list_empty(&anchor->urb_list)) { - victim = list_entry(anchor->urb_list.prev, struct urb, - anchor_list); - __usb_unanchor_urb(victim, anchor); - } - spin_unlock_irqrestore(&anchor->lock, flags); + spin_unlock_irqrestore(&anchor->lock, flags); + cpu_relax(); + } while (!surely_empty); } EXPORT_SYMBOL_GPL(usb_scuttle_anchored_urbs); |