USB: extension of anchor API to unpoison an anchor

This extension allows unpoisoning an anchor allowing drivers that resubmit URBs to reuse an anchor for methods like resume() Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
git-mirror · Jan 7, 2009 · 856395d · 856395d
1 parent 42c6539
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diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
@@ -678,6 +678,26 @@ void usb_poison_anchored_urbs(struct usb_anchor *anchor)
 }
 EXPORT_SYMBOL_GPL(usb_poison_anchored_urbs);
 
+/**
+ * usb_unpoison_anchored_urbs - let an anchor be used successfully again
+ * @anchor: anchor the requests are bound to
+ *
+ * Reverses the effect of usb_poison_anchored_urbs
+ * the anchor can be used normally after it returns
+ */
+void usb_unpoison_anchored_urbs(struct usb_anchor *anchor)
+{
+	unsigned long flags;
+	struct urb *lazarus;
+
+	spin_lock_irqsave(&anchor->lock, flags);
+	list_for_each_entry(lazarus, &anchor->urb_list, anchor_list) {
+		usb_unpoison_urb(lazarus);
+	}
+	anchor->poisoned = 0;
+	spin_unlock_irqrestore(&anchor->lock, flags);
+}
+EXPORT_SYMBOL_GPL(usb_unpoison_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
@@ -1485,6 +1485,7 @@ 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_unpoison_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);