NFSv4: Set a barrier in the update_changeattr() helper

Ensure that we don't regress the changes that were made to the
directory.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>

2 files changed, 2 insertions, 0 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index c66c1df467f4..5026c44a98e1 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1249,6 +1249,7 @@ unsigned long nfs_inc_attr_generation_counter(void)
 {
         return atomic_long_inc_return(&nfs_attr_generation_counter);
 }
+EXPORT_SYMBOL_GPL(nfs_inc_attr_generation_counter);
 
 void nfs_fattr_init(struct nfs_fattr *fattr)
 {
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index b022e64b76a5..a211daf58c32 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -901,6 +901,7 @@ static void update_changeattr(struct inode *dir, struct nfs4_change_info *cinfo)
         if (!cinfo->atomic || cinfo->before != dir->i_version)
                 nfs_force_lookup_revalidate(dir);
         dir->i_version = cinfo->after;
+        nfsi->attr_gencount = nfs_inc_attr_generation_counter();
         nfs_fscache_invalidate(dir);
         spin_unlock(&dir->i_lock);
 }