Commit fe1a9cbc moved the flush_all routine from the bdrv layer to the block-backend layer. In doing so, however, the semantics of the routine changed slightly such that flush_all now used blk_flush instead of bdrv_flush.
blk_flush can fail if the attached device model reports that it is not "available," (i.e. the tray is open.) This changed the semantics of flush_all such that it can now fail for e.g. open CDROM drives. Reintroduce bdrv_flush_all to regain the old semantics without having to alter the behavior of blk_flush or blk_flush_all, which are already 'doing the right thing.' Signed-off-by: John Snow <js...@redhat.com> --- block/io.c | 25 +++++++++++++++++++++++++ include/block/block.h | 1 + 2 files changed, 26 insertions(+) diff --git a/block/io.c b/block/io.c index fdf7080..913df51 100644 --- a/block/io.c +++ b/block/io.c @@ -1619,6 +1619,31 @@ int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, BDRV_REQ_ZERO_WRITE | flags); } +/* + * Flush ALL BDSes regardless of if they are reachable via a BlkBackend or not. + */ +int bdrv_flush_all(void) +{ + BdrvNextIterator it; + BlockDriverState *bs = NULL; + int result = 0; + + for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { + AioContext *aio_context = bdrv_get_aio_context(bs); + int ret; + + aio_context_acquire(aio_context); + ret = bdrv_flush(bs); + if (ret < 0 && !result) { + result = ret; + } + aio_context_release(aio_context); + } + + return result; +} + + typedef struct BdrvCoGetBlockStatusData { BlockDriverState *bs; BlockDriverState *base; diff --git a/include/block/block.h b/include/block/block.h index ffecebf..5e81281 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -332,6 +332,7 @@ int bdrv_inactivate_all(void); /* Ensure contents are flushed to disk. */ int bdrv_flush(BlockDriverState *bs); int coroutine_fn bdrv_co_flush(BlockDriverState *bs); +int bdrv_flush_all(void); void bdrv_close_all(void); void bdrv_drain(BlockDriverState *bs); void coroutine_fn bdrv_co_drain(BlockDriverState *bs); -- 2.7.4