ceph: fix race between aborted requests and fill_trace

When we abort requests we need to prevent fill_trace et al from doing
anything that relies on locks held by the VFS caller.  This fixes a race
between the reply handler and the abort code, ensuring that continue
holding the dir mutex until the reply handler completes.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 0b1dd10be39..141a265bda7 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -165,6 +165,8 @@ struct ceph_mds_request {
         struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */
         struct inode *r_target_inode;       /* resulting inode */
 
+        struct mutex r_fill_mutex;
+
         union ceph_mds_request_args r_args;
         int r_fmode;        /* file mode, if expecting cap */