From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40379) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g6vSN-0004qa-MH for qemu-devel@nongnu.org; Mon, 01 Oct 2018 06:29:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g6vSK-0002LM-PX for qemu-devel@nongnu.org; Mon, 01 Oct 2018 06:29:39 -0400 From: Vladimir Sementsov-Ogievskiy Date: Mon, 1 Oct 2018 13:29:12 +0300 Message-Id: <20181001102928.20533-3-vsementsov@virtuozzo.com> In-Reply-To: <20181001102928.20533-1-vsementsov@virtuozzo.com> References: <20181001102928.20533-1-vsementsov@virtuozzo.com> Subject: [Qemu-devel] [PATCH v3 02/18] block/io: allow BDRV_REQ_SERIALISING for read List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, qemu-block@nongnu.org Cc: eblake@redhat.com, armbru@redhat.com, xiechanglong.d@gmail.com, wencongyang2@huawei.com, stefanha@redhat.com, jsnow@redhat.com, famz@redhat.com, jcody@redhat.com, mreitz@redhat.com, kwolf@redhat.com, vsementsov@virtuozzo.com, den@openvz.org It will be used in further commit, changing backup architecture. Signed-off-by: Vladimir Sementsov-Ogievskiy --- block/io.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/block/io.c b/block/io.c index bd9d688f8b..b003b4d5bf 100644 --- a/block/io.c +++ b/block/io.c @@ -1318,10 +1318,11 @@ static int coroutine_fn bdrv_aligned_preadv(BdrvChild *child, * potential fallback support, if we ever implement any read flags * to pass through to drivers. For now, there aren't any * passthrough flags. */ - assert(!(flags & ~(BDRV_REQ_NO_SERIALISING | BDRV_REQ_COPY_ON_READ))); + assert(!(flags & ~(BDRV_REQ_NO_SERIALISING | BDRV_REQ_COPY_ON_READ | + BDRV_REQ_SERIALISING))); /* Handle Copy on Read and associated serialisation */ - if (flags & BDRV_REQ_COPY_ON_READ) { + if (flags & (BDRV_REQ_COPY_ON_READ | BDRV_REQ_SERIALISING)) { /* If we touch the same cluster it counts as an overlap. This * guarantees that allocating writes will be serialized and not race * with each other for the same cluster. For example, in copy-on-read @@ -1330,9 +1331,6 @@ static int coroutine_fn bdrv_aligned_preadv(BdrvChild *child, mark_request_serialising(req, bdrv_get_cluster_size(bs)); } - /* BDRV_REQ_SERIALISING is only for write operation */ - assert(!(flags & BDRV_REQ_SERIALISING)); - if (!(flags & BDRV_REQ_NO_SERIALISING)) { wait_serialising_requests(req); } @@ -3027,8 +3025,9 @@ static int coroutine_fn bdrv_co_copy_range_internal( tracked_request_begin(&req, src->bs, src_offset, bytes, BDRV_TRACKED_READ); - /* BDRV_REQ_SERIALISING is only for write operation */ - assert(!(read_flags & BDRV_REQ_SERIALISING)); + if (read_flags & BDRV_REQ_SERIALISING) { + mark_request_serialising(&req, bdrv_get_cluster_size(src->bs)); + } if (!(read_flags & BDRV_REQ_NO_SERIALISING)) { wait_serialising_requests(&req); } -- 2.18.0