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 <zyan@redhat.com>
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 424b5b5..faf9209 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -96,6 +96,7 @@
}
cf->fmode = fmode;
cf->next_offset = 2;
+ cf->readdir_cache_idx = -1;
file->private_data = cf;
BUG_ON(inode->i_fop->release != ceph_release);
break;
@@ -324,7 +325,6 @@
ceph_mdsc_put_request(cf->last_readdir);
kfree(cf->last_name);
kfree(cf->dir_info);
- dput(cf->dentry);
kmem_cache_free(ceph_file_cachep, cf);
/* wake up anyone waiting for caps on this inode */