Adding list roles operation
diff --git a/openstack/identity/v2/extensions/admin/roles/requests.go b/openstack/identity/v2/extensions/admin/roles/requests.go
new file mode 100644
index 0000000..a748fff
--- /dev/null
+++ b/openstack/identity/v2/extensions/admin/roles/requests.go
@@ -0,0 +1,13 @@
+package roles
+
+import (
+	"github.com/rackspace/gophercloud"
+	"github.com/rackspace/gophercloud/pagination"
+)
+
+func List(client *gophercloud.ServiceClient) pagination.Pager {
+	createPage := func(r pagination.PageResult) pagination.Page {
+		return RolePage{pagination.SinglePageBase(r)}
+	}
+	return pagination.NewPager(client, rootURL(client), createPage)
+}