BMC/Intel-BMC/linux.git/fs/ceph/super.h, branch dev

ceph: always re-send cap flushes when MDS recovers

2015-07-31T08:38:53+00:00

commit e548e9b93d3e565e42b938a99804114565be1f81 makes the kclient only re-send cap flush once during MDS failover. If the kclient sends a cap flush after MDS enters reconnect stage but before MDS recovers. The kclient will skip re-sending the same cap flush when MDS recovers. This causes problem for newly created inode. The MDS handles cap flushes before replaying unsafe requests, so it's possible that MDS find corresponding inode is missing when handling cap flush. The fix is reverting to old behaviour: always re-send when MDS recovers Signed-off-by: Yan, Zheng Signed-off-by: Ilya Dryomov

ceph: rework dcache readdir

2015-06-25T08:49:32+00:00

Previously our dcache readdir code relies on that child dentries in directory dentry's d_subdir list are sorted by dentry's offset in descending order. When adding dentries to the dcache, if a dentry already exists, our readdir code moves it to head of directory dentry's d_subdir list. This design relies on dcache internals. Al Viro suggests using ncpfs's approach: keeping array of pointers to dentries in page cache of directory inode. the validity of those pointers are presented by directory inode's complete and ordered flags. When a dentry gets pruned, we clear directory inode's complete flag in the d_prune() callback. Before moving a dentry to other directory, we clear the ordered flag for both old and new directory. Signed-off-by: Yan, Zheng

ceph: pre-allocate data structure that tracks caps flushing

2015-06-25T08:49:31+00:00

Signed-off-by: Yan, Zheng

ceph: re-send flushing caps (which are revoked) in reconnect stage

2015-06-25T08:49:31+00:00

if flushing caps were revoked, we should re-send the cap flush in client reconnect stage. This guarantees that MDS processes the cap flush message before issuing the flushing caps to other client. Signed-off-by: Yan, Zheng

ceph: track pending caps flushing globally

2015-06-25T08:49:31+00:00

So we know TID of the oldest pending caps flushing. Later patch will send this information to MDS, so that MDS can trim its completed caps flush list. Tracking pending caps flushing globally also simplifies syncfs code. Signed-off-by: Yan, Zheng

ceph: track pending caps flushing accurately

2015-06-25T08:49:30+00:00

Previously we do not trace accurate TID for flushing caps. when MDS failovers, we have no choice but to re-send all flushing caps with a new TID. This can cause problem because MDS can has already flushed some caps and has issued the same caps to other client. The re-sent cap flush has a new TID, which makes MDS unable to detect if it has already processed the cap flush. This patch adds code to track pending caps flushing accurately. When re-sending cap flush is needed, we use its original flush TID. Signed-off-by: Yan, Zheng

ceph: don't pre-allocate space for cap release messages

2015-06-25T08:49:29+00:00

Previously we pre-allocate cap release messages for each caps. This wastes lots of memory when there are large amount of caps. This patch make the code not pre-allocate the cap release messages. Instead, we add the corresponding ceph_cap struct to a list when releasing a cap. Later when flush cap releases is needed, we allocate the cap release messages dynamically. Signed-off-by: Yan, Zheng

ceph: avoid sending unnessesary FLUSHSNAP message

2015-06-25T08:49:28+00:00

when a snap notification contains no new snapshot, we can avoid sending FLUSHSNAP message to MDS. But we still need to create cap_snap in some case because it's required by write path and page writeback path Signed-off-by: Yan, Zheng

ceph: use empty snap context for uninline_data and get_pool_perm

2015-06-25T08:49:28+00:00

Cached_context in ceph_snap_realm is directly accessed by uninline_data() and get_pool_perm(). This is racy in theory. both uninline_data() and get_pool_perm() do not modify existing object, they only create new object. So we can pass the empty snap context to them. Unlike cached_context in ceph_snap_realm, we do not need to protect the empty snap context. Signed-off-by: Yan, Zheng

ceph: check OSD caps before read/write

2015-06-25T08:49:28+00:00

Signed-off-by: Yan, Zheng