ceph: fix readdir vs fragmentation race (f72f9455) · Commits · 戴 / test

following sequence of events tigger the race - client readdir frag 0* -> got item 'A' - MDS merges frag 0* and frag 1* - client send readdir request (frag 1*, offset 2, readdir_start 'A') - MDS reply items (that are after item 'A') in frag * Link: http://tracker.ceph.com/issues/17286 Signed-off-by:

Yan, Zheng <zyan@redhat.com>

fs/ceph/inode.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -1511,7 +1511,8 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
		ceph_fill_dirfrag(d_inode(parent), rinfo->dir_dir);
		}

		if (ceph_frag_is_leftmost(frag) && req->r_readdir_offset == 2) {
		if (ceph_frag_is_leftmost(frag) && req->r_readdir_offset == 2 &&
		!(rinfo->hash_order && req->r_path2)) {
		/* note dir version at start of readdir so we can tell
		* if any dentries get dropped */
		req->r_dir_release_cnt = atomic64_read(&ci->i_release_count);

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