NFS: Fix another O_DIRECT race

 Ensure we call unmap_mapping_range() and sync dirty pages to disk before
 doing an NFS direct write.

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

1 files changed, 4 insertions, 19 deletions

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 57d3e77d97ee..eb5cd4c3bbfd 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -433,11 +433,7 @@ static int do_unlk(struct file *filp, int cmd, struct file_lock *fl)
          * Flush all pending writes before doing anything
          * with locks..
          */
-        filemap_fdatawrite(filp->f_mapping);
-        down(&inode->i_sem);
-        nfs_wb_all(inode);
-        up(&inode->i_sem);
-        filemap_fdatawait(filp->f_mapping);
+        nfs_sync_mapping(filp->f_mapping);
 
         /* NOTE: special case
          *      If we're signalled while cleaning up locks on process exit, we
@@ -465,15 +461,8 @@ static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
          * Flush all pending writes before doing anything
          * with locks..
          */
-        status = filemap_fdatawrite(filp->f_mapping);
-        if (status == 0) {
-                down(&inode->i_sem);
-                status = nfs_wb_all(inode);
-                up(&inode->i_sem);
-                if (status == 0)
-                        status = filemap_fdatawait(filp->f_mapping);
-        }
-        if (status < 0)
+        status = nfs_sync_mapping(filp->f_mapping);
+        if (status != 0)
                 goto out;
 
         lock_kernel();
@@ -497,11 +486,7 @@ static int do_setlk(struct file *filp, int cmd, struct file_lock *fl)
          * Make sure we clear the cache whenever we try to get the lock.
          * This makes locking act as a cache coherency point.
          */
-        filemap_fdatawrite(filp->f_mapping);
-        down(&inode->i_sem);
-        nfs_wb_all(inode);      /* we may have slept */
-        up(&inode->i_sem);
-        filemap_fdatawait(filp->f_mapping);
+        nfs_sync_mapping(filp->f_mapping);
         nfs_zap_caches(inode);
 out:
         rpc_clnt_sigunmask(NFS_CLIENT(inode), &oldset);