ceph: don't take s_mutex in ceph_flush_snaps

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 6fae3cb..3fe9ea3 100644 (file)
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1531,7 +1531,7 @@ static inline int __send_flush_snap(struct inode *inode,
  * asynchronously back to the MDS once sync writes complete and dirty
  * data is written out.
  *
- * Called under i_ceph_lock.  Takes s_mutex as needed.
+ * Called under i_ceph_lock.
  */
 static void __ceph_flush_snaps(struct ceph_inode_info *ci,
                               struct ceph_mds_session *session)
@@ -1653,7 +1653,6 @@ retry:
        mds = ci->i_auth_cap->session->s_mds;
        if (session && session->s_mds != mds) {
                dout(" oops, wrong session %p mutex\n", session);
-               mutex_unlock(&session->s_mutex);
                ceph_put_mds_session(session);
                session = NULL;
        }
@@ -1662,10 +1661,6 @@ retry:
                mutex_lock(&mdsc->mutex);
                session = __ceph_lookup_mds_session(mdsc, mds);
                mutex_unlock(&mdsc->mutex);
-               if (session) {
-                       dout(" inverting session/ino locks on %p\n", session);
-                       mutex_lock(&session->s_mutex);
-               }
                goto retry;
        }
 
@@ -1677,12 +1672,10 @@ retry:
 out:
        spin_unlock(&ci->i_ceph_lock);
 
-       if (psession) {
+       if (psession)
                *psession = session;
-       } else if (session) {
-               mutex_unlock(&session->s_mutex);
+       else
                ceph_put_mds_session(session);
-       }
        /* we flushed them all; remove this inode from the queue */
        spin_lock(&mdsc->snap_flush_lock);
        list_del_init(&ci->i_snap_flush_item);

diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index f8cac2a..8ca95d1 100644 (file)
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -846,10 +846,7 @@ static void flush_snaps(struct ceph_mds_client *mdsc)
        }
        spin_unlock(&mdsc->snap_flush_lock);
 
-       if (session) {
-               mutex_unlock(&session->s_mutex);
-               ceph_put_mds_session(session);
-       }
+       ceph_put_mds_session(session);
        dout("flush_snaps done\n");
 }