From 23ed6e13b320b33decb516cbe66e71b132df488d Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Wed, 6 Feb 2013 13:11:38 -0600 Subject: [PATCH] rbd: ignore result of ceph_copy_from_page_vector() The result of ceph_copy_from_page_vector() is simply the length argument it is provided. This is called by rbd_obj_method_sync(), which returns the result if it's non-negative. But we always either ignore or overwrite that return value. So explicitly ignore what's returned by the copy function, and have rbd_obj_method_sync() always return either a negative errno or 0. We also return the result of ceph_copy_from_page_vector() in rbd_obj_read_sync(). There we still want to return the number of bytes transferred, but we can use the value we already have in hand rather than what ceph_copy_from_page_vector() provides. Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- drivers/block/rbd.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 93369a1a08e..c259b4089e9 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1889,7 +1889,8 @@ static int rbd_obj_method_sync(struct rbd_device *rbd_dev, ret = obj_request->result; if (ret < 0) goto out; - ret = ceph_copy_from_page_vector(pages, inbound, 0, + ret = 0; + (void) ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred); if (version) *version = obj_request->version; @@ -2088,7 +2089,9 @@ static int rbd_obj_read_sync(struct rbd_device *rbd_dev, rbd_assert(obj_request->xferred <= (u64) SIZE_MAX); size = (size_t) obj_request->xferred; - ret = ceph_copy_from_page_vector(pages, buf, 0, size); + (void) ceph_copy_from_page_vector(pages, buf, 0, size); + rbd_assert(size <= (size_t) INT_MAX); + ret = (int) size; if (version) *version = obj_request->version; out: @@ -2141,7 +2144,6 @@ rbd_dev_v1_header_read(struct rbd_device *rbd_dev, u64 *version) ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name, 0, size, (char *) ondisk, version); - if (ret < 0) goto out_err; if (WARN_ON((size_t) ret < size)) { @@ -2803,7 +2805,6 @@ static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev) dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); if (ret < 0) goto out; - ret = 0; /* rbd_obj_method_sync() can return positive */ p = reply_buf; rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p, @@ -3742,7 +3743,6 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev) dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); if (ret < 0) goto out; - ret = 0; /* rbd_obj_method_sync() can return positive */ p = response; rbd_dev->spec->image_id = ceph_extract_encoded_string(&p, -- 2.46.0