[PATCH] NFS: Fix races in nfs_revalidate_mapping()

Prevent the call to invalidate_inode_pages2() from racing with file writes
by taking the inode->i_mutex across the page cache flush and invalidate.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c
index 6c686112cc03..525c136c7d8c 100644
--- a/fs/nfs/symlink.c
+++ b/fs/nfs/symlink.c
@@ -50,7 +50,9 @@ static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
         struct inode *inode = dentry->d_inode;
         struct page *page;
-        void *err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping));
+        void *err;
+
+        err = ERR_PTR(nfs_revalidate_mapping_nolock(inode, inode->i_mapping));
         if (err)
                 goto read_failed;
         page = read_cache_page(&inode->i_data, 0,