pass default dentry_operations to mount_pseudo()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
index d92d5b5..ac76da0 100644
--- a/arch/ia64/kernel/perfmon.c
+++ b/arch/ia64/kernel/perfmon.c
@@ -617,11 +617,14 @@
 	return get_unmapped_area(file, addr, len, pgoff, flags);
 }
 
+/* forward declaration */
+static static const struct dentry_operations pfmfs_dentry_operations;
 
 static struct dentry *
 pfmfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data)
 {
-	return mount_pseudo(fs_type, "pfm:", NULL, PFMFS_MAGIC);
+	return mount_pseudo(fs_type, "pfm:", NULL, &pfmfs_dentry_operations,
+			PFMFS_MAGIC);
 }
 
 static struct file_system_type pfm_fs_type = {
@@ -2232,7 +2235,6 @@
 	}
 	path.mnt = mntget(pfmfs_mnt);
 
-	d_set_d_op(path.dentry, &pfmfs_dentry_operations);
 	d_add(path.dentry, inode);
 
 	file = alloc_file(&path, FMODE_READ, &pfm_file_ops);