On Wed, Oct 21, 2015 at 10:06:47AM +0800, Fam Zheng wrote: > Drivers can have internal request sources that generate IO, like the > need_check_timer in QED. Since we want quiesced periods that contain > nested event loops in block layer, we need to have a way to disable such > event sources. > > Block drivers must implement the "bdrv_drain" callback if it has any > internal sources that can generate I/O activity, like a timer or a > worker thread (even in a library) that can schedule QEMUBH in an > asynchronous callback. > > Update the comments of bdrv_drain and bdrv_drained_begin accordingly. > > Signed-off-by: Fam Zheng <f...@redhat.com>
Reviewed-by: Jeff Cody <jc...@redhat.com>
