From 2df3fac75851dc4257b90dc72fdd3cf27ba177bc Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Mon, 6 May 2013 09:51:30 -0500 Subject: [PATCH] rbd: define rbd_dev_v2_header_info() This rearranges rbd_dev_v2_refresh() so it works more like rbd_dev_v1_header_info(). While format 1 images need to read the whole header object to get any information, format 2 can collect almost all information selectively. So the one-time initialization will remain in a separate function--based on rbd_dev_v2_probe(). Rename rbd_dev_v2_refresh() to be rbd_dev_v2_header_info(), and have it call rbd_dev_v2_header_onetime() if it's being called for the first time for the given rbd device. Rename rbd_dev_v2_probe() to be rbd_dev_v2_header_onetime() and remove the image size and snapshot context calls it held in common with the refresh function. Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- drivers/block/rbd.c | 42 ++++++++++++++++++------------------------ 1 file changed, 18 insertions(+), 24 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 6748fe2d67d6..0d874a546949 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -425,7 +425,8 @@ static void rbd_img_parent_read(struct rbd_obj_request *obj_request); static void rbd_dev_remove_parent(struct rbd_device *rbd_dev); static int rbd_dev_refresh(struct rbd_device *rbd_dev); -static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev); +static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev); +static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev); static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, u64 snap_id); static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, @@ -3135,7 +3136,7 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev) if (rbd_dev->image_format == 1) ret = rbd_dev_v1_header_info(rbd_dev); else - ret = rbd_dev_v2_refresh(rbd_dev); + ret = rbd_dev_v2_header_info(rbd_dev); /* If it's a mapped snapshot, validate its EXISTS flag */ @@ -4005,12 +4006,19 @@ out: return snap_name; } -static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev) +static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev) { + bool first_time = rbd_dev->header.object_prefix == NULL; int ret; down_write(&rbd_dev->header_rwsem); + if (first_time) { + ret = rbd_dev_v2_header_onetime(rbd_dev); + if (ret) + goto out; + } + ret = rbd_dev_v2_image_size(rbd_dev); if (ret) goto out; @@ -4459,22 +4467,18 @@ static void rbd_dev_unprobe(struct rbd_device *rbd_dev) memset(header, 0, sizeof (*header)); } -static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) +static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev) { int ret; - ret = rbd_dev_v2_image_size(rbd_dev); - if (ret) - goto out_err; - - /* Get the object prefix (a.k.a. block_name) for the image */ - ret = rbd_dev_v2_object_prefix(rbd_dev); if (ret) goto out_err; - /* Get the and check features for the image */ - + /* + * Get the and check features for the image. Currently the + * features are assumed to never change. + */ ret = rbd_dev_v2_features(rbd_dev); if (ret) goto out_err; @@ -4504,17 +4508,7 @@ static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) if (ret < 0) goto out_err; } - - /* crypto and compression type aren't (yet) supported for v2 images */ - - rbd_dev->header.crypt_type = 0; - rbd_dev->header.comp_type = 0; - - /* Get the snapshot context, plus the header version */ - - ret = rbd_dev_v2_snap_context(rbd_dev); - if (ret) - goto out_err; + /* No support for crypto and compression type format 2 images */ return 0; out_err: @@ -4703,7 +4697,7 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool read_only) if (rbd_dev->image_format == 1) ret = rbd_dev_v1_header_info(rbd_dev); else - ret = rbd_dev_v2_probe(rbd_dev); + ret = rbd_dev_v2_header_info(rbd_dev); if (ret) goto err_out_watch; -- 2.20.1