1 files changed, 16 insertions, 1 deletions

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index f3a2abf28a77..98b6e50bde04 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -61,6 +61,14 @@ struct inode *ceph_get_inode(struct super_block *sb, struct ceph_vino vino)
         return inode;
 }
 
+struct inode *ceph_lookup_inode(struct super_block *sb, struct ceph_vino vino)
+{
+        struct inode *inode;
+        ino_t t = ceph_vino_to_ino(vino);
+        inode = ilookup5_nowait(sb, t, ceph_ino_compare, &vino);
+        return inode;
+}
+
 /*
  * get/constuct snapdir inode for a given directory
  */
@@ -1465,7 +1473,14 @@ static void ceph_vmtruncate_work(struct work_struct *work)
         struct inode *inode = &ci->vfs_inode;
 
         dout("vmtruncate_work %p\n", inode);
-        mutex_lock(&inode->i_mutex);
+        if (!mutex_trylock(&inode->i_mutex)) {
+                /*
+                 * the i_mutex can be hold by a writer who is waiting for
+                 * caps. wake up waiters, they will do pending vmtruncate.
+                 */
+                wake_up_all(&ci->i_cap_wq);
+                mutex_lock(&inode->i_mutex);
+        }
         __ceph_do_pending_vmtruncate(inode);
         mutex_unlock(&inode->i_mutex);
         iput(inode);