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 <kw...@redhat.com> Signed-off-by: Sergio Lopez <s...@redhat.com> --- block/block-backend.c | 7 ++++++- include/sysemu/block-backend.h | 4 ++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/block/block-backend.c b/block/block-backend.c index de5496af66..163ca05b97 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -2393,8 +2393,13 @@ static void blk_root_drained_begin(BdrvChild *child) static bool blk_root_drained_poll(BdrvChild *child) { BlockBackend *blk = child->opaque; + int ret = 0; assert(blk->quiesce_counter); - return !!blk->in_flight; + + if (blk->dev_ops && blk->dev_ops->drained_poll) { + ret = blk->dev_ops->drained_poll(blk->dev_opaque); + } + return ret || !!blk->in_flight; } static void blk_root_drained_end(BdrvChild *child, int *drained_end_counter) diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h index 880e903293..9992072e18 100644 --- a/include/sysemu/block-backend.h +++ b/include/sysemu/block-backend.h @@ -66,6 +66,10 @@ typedef struct BlockDevOps { * Runs when the backend's last drain request ends. */ void (*drained_end)(void *opaque); + /* + * Is the device drained? + */ + bool (*drained_poll)(void *opaque); } BlockDevOps; /* This struct is embedded in (the private) BlockBackend struct and contains -- 2.26.2