ceph: allocate cap_release message when receiving cap import

When client wants to release an imported cap, it's possible there
is no reserved cap_release message in corresponding mds session.
so __queue_cap_release causes kernel panic.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 76b19239c426..40b5bbe63a39 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -2833,6 +2833,9 @@ void ceph_handle_caps(struct ceph_mds_session *session,
         dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
              (unsigned)seq);
 
+        if (op == CEPH_CAP_OP_IMPORT)
+                ceph_add_cap_releases(mdsc, session);
+
         /* lookup ino */
         inode = ceph_find_inode(sb, vino);
         ci = ceph_inode(inode);