ceph: unlock dangling spinlock in try_flush_caps()

sparse warns:

  fs/ceph/caps.c:2042:9: warning: context imbalance in 'try_flush_caps' - wrong count at exit

We need to exit this function with the lock unlocked, but a couple of
cases leave it locked.

Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 157fe59fbabe..1978a8cb1cb1 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1991,6 +1991,7 @@ static int try_flush_caps(struct inode *inode, u64 *ptid)
 retry:
         spin_lock(&ci->i_ceph_lock);
         if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
+                spin_unlock(&ci->i_ceph_lock);
                 dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
                 goto out;
         }
@@ -2008,8 +2009,10 @@ retry:
                         mutex_lock(&session->s_mutex);
                         goto retry;
                 }
-                if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
+                if (cap->session->s_state < CEPH_MDS_SESSION_OPEN) {
+                        spin_unlock(&ci->i_ceph_lock);
                         goto out;
+                }
 
                 flushing = __mark_caps_flushing(inode, session, true,
                                                 &flush_tid, &oldest_flush_tid);