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author | Oliver Neukum <oliver@neukum.org> | 2008-04-10 14:07:37 +0200 |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-04-24 21:16:50 -0700 |
commit | eda769593bbae8aee4e336b0732f6016353301a3 (patch) | |
tree | 04b5aae8d2cf133b86527b56505c26841b9f45f8 /drivers/usb/core | |
parent | 9424ea29658ce5bcdcf527ddf9617b9507ddf1aa (diff) | |
download | linux-eda769593bbae8aee4e336b0732f6016353301a3.tar.gz linux-eda769593bbae8aee4e336b0732f6016353301a3.tar.bz2 linux-eda769593bbae8aee4e336b0732f6016353301a3.zip |
USB: add extension of anchor API, usb_unlink_anchored_urbs
This adds the ability to trigger asynchronous unlinks of anchored URBs. This
is needed for error handling in the comntext of completion handlers, which
cannot sleep.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/core')
-rw-r--r-- | drivers/usb/core/urb.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c index 9d7e63292c01..1d3ed1322fbe 100644 --- a/drivers/usb/core/urb.c +++ b/drivers/usb/core/urb.c @@ -590,6 +590,30 @@ void usb_kill_anchored_urbs(struct usb_anchor *anchor) EXPORT_SYMBOL_GPL(usb_kill_anchored_urbs); /** + * usb_unlink_anchored_urbs - asynchronously cancel transfer requests en masse + * @anchor: anchor the requests are bound to + * + * this allows all outstanding URBs to be unlinked starting + * from the back of the queue. This function is asynchronous. + * The unlinking is just tiggered. It may happen after this + * function has returned. + */ +void usb_unlink_anchored_urbs(struct usb_anchor *anchor) +{ + struct urb *victim; + + spin_lock_irq(&anchor->lock); + while (!list_empty(&anchor->urb_list)) { + victim = list_entry(anchor->urb_list.prev, struct urb, + anchor_list); + /* this will unanchor the URB */ + usb_unlink_urb(victim); + } + spin_unlock_irq(&anchor->lock); +} +EXPORT_SYMBOL_GPL(usb_unlink_anchored_urbs); + +/** * usb_wait_anchor_empty_timeout - wait for an anchor to be unused * @anchor: the anchor you want to become unused * @timeout: how long you are willing to wait in milliseconds |