diff options
| -rw-r--r-- | drivers/usb/core/urb.c | 57 | ||||
| -rw-r--r-- | include/linux/usb.h | 2 |
2 files changed, 50 insertions, 9 deletions
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c index a7945ab208c2..eebc070c3cc7 100644 --- a/drivers/usb/core/urb.c +++ b/drivers/usb/core/urb.c @@ -10,6 +10,8 @@ #define to_urb(d) container_of(d, struct urb, kref) +static DEFINE_SPINLOCK(usb_reject_lock); + static void urb_destroy(struct kref *kref) { struct urb *urb = to_urb(kref); @@ -127,6 +129,13 @@ void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor) usb_get_urb(urb); list_add_tail(&urb->anchor_list, &anchor->urb_list); urb->anchor = anchor; + + if (unlikely(anchor->poisoned)) { + spin_lock(&usb_reject_lock); + urb->reject++; + spin_unlock(&usb_reject_lock); + } + spin_unlock_irqrestore(&anchor->lock, flags); } EXPORT_SYMBOL_GPL(usb_anchor_urb); @@ -522,7 +531,6 @@ int usb_unlink_urb(struct urb *urb) } EXPORT_SYMBOL_GPL(usb_unlink_urb); -static DEFINE_MUTEX(usb_reject_mutex); /** * usb_kill_urb - cancel a transfer request and wait for it to finish * @urb: pointer to URB describing a previously submitted request, @@ -548,16 +556,16 @@ void usb_kill_urb(struct urb *urb) might_sleep(); if (!(urb && urb->dev && urb->ep)) return; - mutex_lock(&usb_reject_mutex); + spin_lock_irq(&usb_reject_lock); ++urb->reject; - mutex_unlock(&usb_reject_mutex); + spin_unlock_irq(&usb_reject_lock); usb_hcd_unlink_urb(urb, -ENOENT); wait_event(usb_kill_urb_queue, atomic_read(&urb->use_count) == 0); - mutex_lock(&usb_reject_mutex); + spin_lock_irq(&usb_reject_lock); --urb->reject; - mutex_unlock(&usb_reject_mutex); + spin_unlock_irq(&usb_reject_lock); } EXPORT_SYMBOL_GPL(usb_kill_urb); @@ -586,9 +594,9 @@ void usb_poison_urb(struct urb *urb) might_sleep(); if (!(urb && urb->dev && urb->ep)) return; - mutex_lock(&usb_reject_mutex); + spin_lock_irq(&usb_reject_lock); ++urb->reject; - mutex_unlock(&usb_reject_mutex); + spin_unlock_irq(&usb_reject_lock); usb_hcd_unlink_urb(urb, -ENOENT); wait_event(usb_kill_urb_queue, atomic_read(&urb->use_count) == 0); @@ -597,12 +605,14 @@ EXPORT_SYMBOL_GPL(usb_poison_urb); void usb_unpoison_urb(struct urb *urb) { + unsigned long flags; + if (!urb) return; - mutex_lock(&usb_reject_mutex); + spin_lock_irqsave(&usb_reject_lock, flags); --urb->reject; - mutex_unlock(&usb_reject_mutex); + spin_unlock_irqrestore(&usb_reject_lock, flags); } EXPORT_SYMBOL_GPL(usb_unpoison_urb); @@ -633,6 +643,35 @@ void usb_kill_anchored_urbs(struct usb_anchor *anchor) } EXPORT_SYMBOL_GPL(usb_kill_anchored_urbs); + +/** + * usb_poison_anchored_urbs - cease all traffic from an anchor + * @anchor: anchor the requests are bound to + * + * this allows all outstanding URBs to be poisoned starting + * from the back of the queue. Newly added URBs will also be + * poisoned + */ +void usb_poison_anchored_urbs(struct usb_anchor *anchor) +{ + struct urb *victim; + + 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); + spin_lock_irq(&anchor->lock); + } + spin_unlock_irq(&anchor->lock); +} +EXPORT_SYMBOL_GPL(usb_poison_anchored_urbs); /** * usb_unlink_anchored_urbs - asynchronously cancel transfer requests en masse * @anchor: anchor the requests are bound to diff --git a/include/linux/usb.h b/include/linux/usb.h index 3371c91e7ff4..d97927970f54 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -1135,6 +1135,7 @@ struct usb_anchor { struct list_head urb_list; wait_queue_head_t wait; spinlock_t lock; + unsigned int poisoned:1; }; static inline void init_usb_anchor(struct usb_anchor *anchor) @@ -1462,6 +1463,7 @@ extern void usb_kill_urb(struct urb *urb); extern void usb_poison_urb(struct urb *urb); extern void usb_unpoison_urb(struct urb *urb); extern void usb_kill_anchored_urbs(struct usb_anchor *anchor); +extern void usb_poison_anchored_urbs(struct usb_anchor *anchor); extern void usb_unlink_anchored_urbs(struct usb_anchor *anchor); extern void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor); extern void usb_unanchor_urb(struct urb *urb); |