NFS: Ensure that NFS file unlock waits for readahead to complete

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 29f4a48a0ee6..a87a44f84113 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -744,6 +744,7 @@ static int
 do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
 {
         struct inode *inode = filp->f_mapping->host;
+        struct nfs_lock_context *l_ctx;
         int status;
 
         /*
@@ -752,6 +753,14 @@ do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
          */
         nfs_sync_mapping(filp->f_mapping);
 
+        l_ctx = nfs_get_lock_context(nfs_file_open_context(filp));
+        if (!IS_ERR(l_ctx)) {
+                status = nfs_iocounter_wait(&l_ctx->io_count);
+                nfs_put_lock_context(l_ctx);
+                if (status < 0)
+                        return status;
+        }
+
         /* NOTE: special case
          *      If we're signalled while cleaning up locks on process exit, we
          *      still need to complete the unlock.