From 70d045f660c7331bce8c9377929b52a9738a12cb Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Fri, 12 Sep 2014 16:02:01 +0400 Subject: [PATCH] rbd: add img_obj_request_simple() helper To clarify the conditions and make it easier to add new ones. Signed-off-by: Ilya Dryomov --- drivers/block/rbd.c | 44 ++++++++++++++++++++++++++++---------------- 1 file changed, 28 insertions(+), 16 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index eea44ce2d537..6dae6586a8a9 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -2743,11 +2743,10 @@ out: return ret; } -static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) +static bool img_obj_request_simple(struct rbd_obj_request *obj_request) { struct rbd_img_request *img_request; struct rbd_device *rbd_dev; - bool known; rbd_assert(obj_request_img_data_test(obj_request)); @@ -2755,22 +2754,35 @@ static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) rbd_assert(img_request); rbd_dev = img_request->rbd_dev; + /* Reads */ + if (!img_request_write_test(img_request)) + return true; + + /* Non-layered writes */ + if (!img_request_layered_test(img_request)) + return true; + /* - * Only writes to layered images need special handling. - * Reads and non-layered writes are simple object requests. - * Layered writes that start beyond the end of the overlap - * with the parent have no parent data, so they too are - * simple object requests. Finally, if the target object is - * known to already exist, its parent data has already been - * copied, so a write to the object can also be handled as a - * simple object request. + * Layered writes outside of the parent overlap range don't + * share any data with the parent. */ - if (!img_request_write_test(img_request) || - !img_request_layered_test(img_request) || - !obj_request_overlaps_parent(obj_request) || - ((known = obj_request_known_test(obj_request)) && - obj_request_exists_test(obj_request))) { + if (!obj_request_overlaps_parent(obj_request)) + return true; + /* + * If the object is known to already exist, its parent data has + * already been copied. + */ + if (obj_request_known_test(obj_request) && + obj_request_exists_test(obj_request)) + return true; + + return false; +} + +static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) +{ + if (img_obj_request_simple(obj_request)) { struct rbd_device *rbd_dev; struct ceph_osd_client *osdc; @@ -2786,7 +2798,7 @@ static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) * start by reading the data for the full target object from * the parent so we can use it for a copyup to the target. */ - if (known) + if (obj_request_known_test(obj_request)) return rbd_img_obj_parent_read_full(obj_request); /* We don't know whether the target exists. Go find out. */ -- 2.30.2