From c622d226155b12276ae3d29d546f4b314d7cd68c Mon Sep 17 00:00:00 2001 From: Guangliang Zhao Date: Tue, 1 Apr 2014 22:22:15 +0800 Subject: [PATCH] rbd: skip the copyup when an entire object writing It need to copyup the parent's content when layered writing, but an entire object write would overwrite it, so skip it. Signed-off-by: Guangliang Zhao Reviewed-by: Josh Durgin Reviewed-by: Alex Elder --- drivers/block/rbd.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 6dae6586a8a9..16eb247cb5fb 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -2769,6 +2769,14 @@ static bool img_obj_request_simple(struct rbd_obj_request *obj_request) if (!obj_request_overlaps_parent(obj_request)) return true; + /* + * Entire-object layered writes - we will overwrite whatever + * parent data there is anyway. + */ + if (!obj_request->offset && + obj_request->length == rbd_obj_bytes(&rbd_dev->header)) + return true; + /* * If the object is known to already exist, its parent data has * already been copied. -- 2.20.1