From 2007b6057d11fc91074987021a66129851fc71d9 Mon Sep 17 00:00:00 2001 From: John Snow Date: Mon, 19 Sep 2016 18:16:10 +0200 Subject: [PATCH 17/18] block: reintroduce bdrv_flush_all RH-Author: John Snow Message-id: <1474308971-28285-2-git-send-email-jsnow@redhat.com> Patchwork-id: 72379 O-Subject: [RHEV-7.3 qemu-kvm-rhev PATCH 1/2] block: reintroduce bdrv_flush_all Bugzilla: 1338638 RH-Acked-by: Max Reitz RH-Acked-by: Markus Armbruster RH-Acked-by: Kevin Wolf 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 Reviewed-by: Kevin Wolf (cherry picked from commit bfb91daf47982137d9dffe16658fbec3407c3fef) Signed-off-by: John Snow Signed-off-by: Miroslav Rezanina Conflicts: qemu-kvm-rhev did not backport the conversion of bdrv_next to use an iterator, so the bdrv_flush_all implementation here differs. Signed-off-by: John Snow Note: Commit hash can be incorrect due early commit (due to deadline) --- block/io.c | 24 ++++++++++++++++++++++++ include/block/block.h | 1 + 2 files changed, 25 insertions(+) diff --git a/block/io.c b/block/io.c index 83c4367..852f360 100644 --- a/block/io.c +++ b/block/io.c @@ -1481,6 +1481,30 @@ int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, BDRV_REQ_ZERO_WRITE | flags); } +/* + * Flush ALL BDSes regardless of if they are reachable via a BlkBackend or not. + */ +int bdrv_flush_all(void) +{ + BlockDriverState *bs = NULL; + int result = 0; + + while ((bs = bdrv_next(bs))) { + 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 3a73137..a4e1833 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -370,6 +370,7 @@ 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); -- 1.8.3.1