From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40196) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1akvHQ-0003mB-7r for qemu-devel@nongnu.org; Tue, 29 Mar 2016 11:10:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1akvHM-0006I3-0t for qemu-devel@nongnu.org; Tue, 29 Mar 2016 11:10:04 -0400 From: Kevin Wolf Date: Tue, 29 Mar 2016 17:08:21 +0200 Message-Id: <1459264128-12761-22-git-send-email-kwolf@redhat.com> In-Reply-To: <1459264128-12761-1-git-send-email-kwolf@redhat.com> References: <1459264128-12761-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 21/48] block: add flush callback List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Pavel Dovgalyuk This patch adds callback for flush request. This callback is responsible for flushing whole block devices stack. bdrv_flush function does not proceed to underlying devices. It should be performed by this callback function, if needed. Signed-off-by: Pavel Dovgalyuk Signed-off-by: Kevin Wolf --- block/io.c | 7 +++++++ include/block/block_int.h | 7 +++++++ 2 files changed, 14 insertions(+) diff --git a/block/io.c b/block/io.c index bfc8592..c447db2 100644 --- a/block/io.c +++ b/block/io.c @@ -2331,6 +2331,13 @@ int coroutine_fn bdrv_co_flush(BlockDriverState *bs) } tracked_request_begin(&req, bs, 0, 0, BDRV_TRACKED_FLUSH); + + /* Write back all layers by calling one driver function */ + if (bs->drv->bdrv_co_flush) { + ret = bs->drv->bdrv_co_flush(bs); + goto out; + } + /* Write back cached data to the OS even with cache=unsafe */ BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS); if (bs->drv->bdrv_co_flush_to_os) { diff --git a/include/block/block_int.h b/include/block/block_int.h index a33b0de..1177c25 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -176,6 +176,13 @@ struct BlockDriver { int (*bdrv_inactivate)(BlockDriverState *bs); /* + * Flushes all data for all layers by calling bdrv_co_flush for underlying + * layers, if needed. This function is needed for deterministic + * synchronization of the flush finishing callback. + */ + int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs); + + /* * Flushes all data that was already written to the OS all the way down to * the disk (for example raw-posix calls fsync()). */ -- 1.8.3.1