diff --git a/include/ircd/cl.h b/include/ircd/cl.h
index 209a8fdfc..991bd0a9a 100644
--- a/include/ircd/cl.h
+++ b/include/ircd/cl.h
@@ -76,6 +76,7 @@ struct ircd::cl::data
 	data(const size_t, const const_buffer &); // device ro
 	data(const mutable_buffer &, const bool wonly = false); // host rw
 	data(const const_buffer &); // host ro
+	data(data &, const pair<size_t, off_t> &); // subbuffer
 	data(const data &) = delete;
 	data() = default;
 	data(data &&) noexcept;
diff --git a/ircd/cl.cc b/ircd/cl.cc
index c7afd2e9d..850001283 100644
--- a/ircd/cl.cc
+++ b/ircd/cl.cc
@@ -1246,6 +1246,20 @@ ircd::cl::data::data(const const_buffer &buf)
 	throw_on_error(err);
 }
 
+ircd::cl::data::data(data &master,
+                     const pair<size_t, off_t> &slice)
+{
+	cl_mem_flags flags {0};
+
+	cl_buffer_region region {0};
+	region.origin = slice.second;
+	region.size = slice.first;
+
+	int err {CL_SUCCESS};
+	handle = clCreateSubBuffer(cl_mem(master.handle), flags, CL_BUFFER_CREATE_TYPE_REGION, &region, &err);
+	throw_on_error(err);
+}
+
 ircd::cl::data::data(data &&o)
 noexcept
 :handle{std::move(o.handle)}