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, 6 insertions, 18 deletions

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index b497c71384e8..079228817603 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -678,15 +678,9 @@ nfs_file_direct_read(struct kiocb *iocb, char __user *buf, size_t count, loff_t
         if (!count)
                 goto out;
 
-        if (mapping->nrpages) {
-                retval = filemap_fdatawrite(mapping);
-                if (retval == 0)
-                        retval = nfs_wb_all(inode);
-                if (retval == 0)
-                        retval = filemap_fdatawait(mapping);
-                if (retval)
-                        goto out;
-        }
+        retval = nfs_sync_mapping(mapping);
+        if (retval)
+                goto out;
 
         retval = nfs_direct_read(inode, ctx, &iov, pos, 1);
         if (retval > 0)
@@ -764,15 +758,9 @@ nfs_file_direct_write(struct kiocb *iocb, const char __user *buf, size_t count,
         if (!count)
                 goto out;
 
-        if (mapping->nrpages) {
-                retval = filemap_fdatawrite(mapping);
-                if (retval == 0)
-                        retval = nfs_wb_all(inode);
-                if (retval == 0)
-                        retval = filemap_fdatawait(mapping);
-                if (retval)
-                        goto out;
-        }
+        retval = nfs_sync_mapping(mapping);
+        if (retval)
+                goto out;
 
         retval = nfs_direct_write(inode, ctx, &iov, pos, 1);
         if (mapping->nrpages)