block-backend: add drained_poll
commit095cc4d0f62513d75e9bc1da37f08d9e97f267c4
authorSergio Lopez <slp@redhat.com>
Wed, 2 Jun 2021 06:05:51 +0000 (2 08:05 +0200)
committerKevin Wolf <kwolf@redhat.com>
Wed, 2 Jun 2021 12:23:20 +0000 (2 14:23 +0200)
tree7e274b2a5d0feb2059bac2b94ef534f1b77a6af1
parent30ebb9aa9203b5051c5c4f4e2421803b94e5f2cc
block-backend: add drained_poll

Allow block backends to poll their devices/users to check if they have
been quiesced when entering a drained section.

This will be used in the next patch to wait for the NBD server to be
completely quiesced.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Sergio Lopez <slp@redhat.com>
Message-Id: <20210602060552.17433-2-slp@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
block/block-backend.c
include/sysemu/block-backend.h