ceph: rework dcache readdir
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 <[email protected]>
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 470be4e..762757e 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -253,6 +253,9 @@
bool r_got_unsafe, r_got_safe, r_got_result;
bool r_did_prepopulate;
+ long long r_dir_release_cnt;
+ long long r_dir_ordered_cnt;
+ int r_readdir_cache_idx;
u32 r_readdir_offset;
struct ceph_cap_reservation r_caps_reservation;
