Commit 6a2839be authored by Oliver Neukum's avatar Oliver Neukum Committed by Greg Kroah-Hartman
Browse files

USB: extend poisoning to anchors 



this extends the poisoning concept to anchors. This way poisoning
will work with fire and forget drivers.

Signed-off-by: default avatarOliver Neukum <oneukum@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 55b447bf

drivers/usb/core/urb.c

+48 −9
Original line number Diff line number Diff line
@@ -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

include/linux/usb.h

+2 −0
Original line number Diff line number Diff line
@@ -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);