From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40851) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7qkL-0002Zh-So for qemu-devel@nongnu.org; Fri, 09 Aug 2013 13:45:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V7qkF-0005nN-V8 for qemu-devel@nongnu.org; Fri, 09 Aug 2013 13:45:05 -0400 Received: from mail6.webfaction.com ([74.55.86.74]:50473 helo=smtp.webfaction.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7qkF-0005nE-Oj for qemu-devel@nongnu.org; Fri, 09 Aug 2013 13:44:59 -0400 From: Charlie Shepherd Date: Fri, 9 Aug 2013 19:43:57 +0200 Message-Id: <1376070245-22557-7-git-send-email-charlie@ctshepherd.com> In-Reply-To: <1376070245-22557-1-git-send-email-charlie@ctshepherd.com> References: <1376070245-22557-1-git-send-email-charlie@ctshepherd.com> Subject: [Qemu-devel] [RFC v2 07/15] Call bdrv->open via a synchronous wrapper in block/snapshot.c List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, stefanha@gmail.com, gabriel@kerneis.info, Charlie Shepherd , pbonzini@redhat.com block/snapshot.c calls bdrv->open directly from a non-coroutine context. Provide a synchronous wrapper to ensure correctness. Signed-off-by: Charlie Shepherd --- block/snapshot.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) diff --git a/block/snapshot.c b/block/snapshot.c index 6c6d9de..541d83d 100644 --- a/block/snapshot.c +++ b/block/snapshot.c @@ -25,6 +25,8 @@ #include "block/snapshot.h" #include "block/block_int.h" +#define NOT_DONE 0x7fffffff + int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info, const char *name) { @@ -81,6 +83,34 @@ int bdrv_snapshot_create(BlockDriverState *bs, return -ENOTSUP; } +struct SnapOp { + BlockDriverState *bs; + int ret; +}; + +static void coroutine_fn bdrv_snapshot_open_entry(void *opaque) +{ + struct SnapOp *so = opaque; + so->ret = so->bs->drv->bdrv_co_open(so->bs, NULL, so->bs->open_flags); +} + +static int bdrv_snapshot_open(BlockDriverState *bs) +{ + Coroutine *co; + struct SnapOp so = { + .bs = bs, + .ret = NOT_DONE, + }; + + co = qemu_coroutine_create(bdrv_snapshot_open_entry); + qemu_coroutine_enter(co, &so); + while (so.ret == NOT_DONE) { + qemu_aio_wait(); + } + + return so.ret; +} + int bdrv_snapshot_goto(BlockDriverState *bs, const char *snapshot_id) { @@ -97,7 +127,7 @@ int bdrv_snapshot_goto(BlockDriverState *bs, if (bs->file) { drv->bdrv_close(bs); ret = bdrv_snapshot_goto(bs->file, snapshot_id); - open_ret = drv->bdrv_open(bs, NULL, bs->open_flags); + open_ret = bdrv_snapshot_open(bs); if (open_ret < 0) { bdrv_delete(bs->file); bs->drv = NULL; -- 1.8.3.2