9p: don't bother with always_delete_dentry

just set DCACHE_DONTCACHE for "don't cache" mounts...

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Author: Al Viro

fs/9p/vfs_dentry.c

@@ -127,7 +127,6 @@ const struct dentry_operations v9fs_cached_dentry_operations = {
 };
 
 const struct dentry_operations v9fs_dentry_operations = {
-	.d_delete = always_delete_dentry,
 	.d_release = v9fs_dentry_release,
 	.d_unalias_trylock = v9fs_dentry_unalias_trylock,
 	.d_unalias_unlock = v9fs_dentry_unalias_unlock,

fs/9p/vfs_super.c

@@ -134,10 +134,12 @@ static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
 	if (retval)
 		goto release_sb;
 
-	if (v9ses->cache & (CACHE_META|CACHE_LOOSE))
+	if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) {
 		set_default_d_op(sb, &v9fs_cached_dentry_operations);
-	else
+	} else {
 		set_default_d_op(sb, &v9fs_dentry_operations);
+		sb->s_d_flags |= DCACHE_DONTCACHE;
+	}
 
 	inode = v9fs_get_new_inode_from_fid(v9ses, fid, sb);
 	if (IS_ERR(inode)) {