Lockdep gripes if file->f_lock is taken in a no-IRQ situation, since that
is not always the case.  We don't really want to disable IRQs for every
acquisition of f_lock; instead, just move it outside of fasync_lock.
Reported-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Reported-by: NLarry Finger <Larry.Finger@lwfinger.net>
Reported-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>