From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53657) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YtA0f-0007SZ-Vq for qemu-devel@nongnu.org; Fri, 15 May 2015 03:26:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YtA0d-0006FM-An for qemu-devel@nongnu.org; Fri, 15 May 2015 03:26:17 -0400 Received: from mail-wg0-x229.google.com ([2a00:1450:400c:c00::229]:35189) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YtA0c-0006FA-VU for qemu-devel@nongnu.org; Fri, 15 May 2015 03:26:15 -0400 Received: by wgnd10 with SMTP id d10so100499927wgn.2 for ; Fri, 15 May 2015 00:26:14 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <55559F92.5050600@redhat.com> Date: Fri, 15 May 2015 09:26:10 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <55554DBD.5000902@cn.fujitsu.com> <55559602.7040405@redhat.com> <555597DC.4090208@cn.fujitsu.com> In-Reply-To: <555597DC.4090208@cn.fujitsu.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3] mirror: correct buf_size List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wen Congyang , qemu-devl , Fam Zheng Cc: Kevin Wolf , Jeff Cody On 15/05/2015 08:53, Wen Congyang wrote: > On 05/15/2015 02:45 PM, Paolo Bonzini wrote: >> >> >> On 15/05/2015 03:37, Wen Congyang wrote: >>> If bus_size is less than 0, the command fails. >>> If buf_size % granularity is not 0, mirror_free_init() will >>> do dangerous things. >>> >>> Signed-off-by: Wen Congyang >>> --- >>> block/mirror.c | 6 +++++- >>> 1 file changed, 5 insertions(+), 1 deletion(-) >>> >>> diff --git a/block/mirror.c b/block/mirror.c >>> index 58f391a..7732f8b 100644 >>> --- a/block/mirror.c >>> +++ b/block/mirror.c >>> @@ -671,6 +671,10 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target, >>> return; >>> } >>> >>> + if (buf_size < 0) { >> >> This should be <=. > > But commit_active_start() passes 0... This was changed to granularity by MAX, while it would be 0 after ROUND_UP. The right value would be DEFAULT_MIRROR_BUF_SIZE. block_commit should have an optional buf_size, but for now I guess you can change a 0 to DEFAULT_MIRROR_BUF_SIZE in mirror_start_job, and let qmp_drive_mirror do this: if (!has_buf_size) { - buf_size = DEFAULT_MIRROR_BUF_SIZE; + buf_size = 0; } Paolo > Thanks > Wen Congyang > >> >> Jeff, can you adjust when committing? >> >> Paolo >> >>> + error_setg(errp, "Invalid parameter '%s'", "buf-size"); >>> + return; >>> + } >>> >>> s = block_job_create(driver, bs, speed, cb, opaque, errp); >>> if (!s) { >>> @@ -684,7 +688,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target, >>> s->is_none_mode = is_none_mode; >>> s->base = base; >>> s->granularity = granularity; >>> - s->buf_size = MAX(buf_size, granularity); >>> + s->buf_size = ROUND_UP(buf_size, granularity); >>> >>> s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp); >>> if (!s->dirty_bitmap) { >>> >> . >> > > >