From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39931) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YuYcx-0006Uw-Io for qemu-devel@nongnu.org; Mon, 18 May 2015 23:55:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YuYcs-0007Fl-JD for qemu-devel@nongnu.org; Mon, 18 May 2015 23:55:35 -0400 From: Fam Zheng Date: Tue, 19 May 2015 11:49:46 +0000 Message-Id: <1432036186-29903-14-git-send-email-famz@redhat.com> In-Reply-To: <1432036186-29903-1-git-send-email-famz@redhat.com> References: <1432036186-29903-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH v4 13/13] block/mirror: Block "device IO" during mirror exit List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , qemu-block@nongnu.org, Juan Quintela , Jeff Cody , "Michael S. Tsirkin" , mreitz@redhat.com, Stefan Hajnoczi , Amit Shah , Paolo Bonzini When block job mirror is finished, the source and target is synced. But we call bdrv_swap() later in main loop bh. If the guest write before that, target will not get the new data. Reported-by: Wen Congyang Signed-off-by: Fam Zheng --- block/mirror.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/block/mirror.c b/block/mirror.c index 58f391a..d96403b 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -320,6 +320,8 @@ static void mirror_drain(MirrorBlockJob *s) typedef struct { int ret; + /* Use to pause device IO during mirror exit */ + Error *blocker; } MirrorExitData; static void mirror_exit(BlockJob *job, void *opaque) @@ -328,6 +330,8 @@ static void mirror_exit(BlockJob *job, void *opaque) MirrorExitData *data = opaque; AioContext *replace_aio_context = NULL; + bdrv_op_unblock(s->common.bs, BLOCK_OP_TYPE_DEVICE_IO, data->blocker); + error_free(data->blocker); if (s->to_replace) { replace_aio_context = bdrv_get_aio_context(s->to_replace); aio_context_acquire(replace_aio_context); @@ -563,8 +567,10 @@ immediate_exit: bdrv_release_dirty_bitmap(bs, s->dirty_bitmap); bdrv_iostatus_disable(s->target); - data = g_malloc(sizeof(*data)); + data = g_malloc0(sizeof(*data)); data->ret = ret; + error_setg(&data->blocker, "mirror job exiting"); + bdrv_op_block(bs, BLOCK_OP_TYPE_DEVICE_IO, data->blocker); block_job_defer_to_main_loop(&s->common, mirror_exit, data); } -- 2.4.1