Provide put & get message passing primitives for the bsp1d backend

include/CMakeLists.txt

@@ -50,7 +50,7 @@ set( root_files
 	"graphblas/io.hpp" "graphblas/iomode.hpp" "graphblas/matrix.hpp"
 	"graphblas/monoid.hpp" "graphblas/ops.hpp" "graphblas/phase.hpp"
 	"graphblas/pinnedvector.hpp" "graphblas/properties.hpp" "graphblas/rc.hpp"
-	"graphblas/semiring.hpp" "graphblas/spmd.hpp" "graphblas/tags.hpp"
+	"graphblas/semiring.hpp" "graphblas/spmd.hpp" "graphblas/rdma.hpp" "graphblas/tags.hpp"
 	"graphblas/type_traits.hpp" "graphblas/utils.hpp" "graphblas/vector.hpp"
 	"graphblas/synchronizedNonzeroIterator.hpp" "graphblas/nonzeroStorage.hpp"
 	"graphblas/selection_ops.hpp"

include/graphblas.hpp

@@ -545,6 +545,7 @@ namespace grb {
 #include <graphblas/pinnedvector.hpp>
 #include <graphblas/properties.hpp>
 #include <graphblas/spmd.hpp>
+#include <graphblas/rdma.hpp>
 
 #ifdef _GRB_WITH_LPF
  // collects various BSP utilities

include/graphblas/base/rdma.hpp

@@ -0,0 +1,93 @@
+
+/*
+ *   Copyright 2021 Huawei Technologies Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @file
+ *
+ * Exposes facilities for Remote Direct Memory Access
+ *
+ * @author G. Gaio
+ * @date 16th of December, 2025
+ */
+
+#ifndef _H_GRB_BASE_RDMA
+#define _H_GRB_BASE_RDMA
+
+#include <cstddef> //size_t
+
+#include <stdint.h> // SIZE_MAX
+
+#include <graphblas/backends.hpp>
+#include <graphblas/rc.hpp>
+
+#include "config.hpp"
+
+
+namespace grb {
+
+	/**
+	 * For backends that support multiple user processes this class defines some
+	 * basic primitives to support RDMA programming.
+	 *
+	 * All backends must implement this interface, including backends that do not
+	 * support multiple user processes. The interface herein defined hence ensures
+	 * to allow for trivial implementations for single user process backends.
+	 */
+	template< Backend implementation >
+	class rdma {
+		public:
+		template< typename T >
+		static inline grb::RC register_global( const T &buf );
+
+		template< typename T >
+		static inline grb::RC register_global( const grb::Vector< T, grb::reference > &buf );
+
+		template< typename T >
+		static inline grb::RC deregister( const T &buf );
+
+		template< typename T >
+		static inline grb::RC deregister( const grb::Vector< T, grb::reference > &buf );
+
+		static inline grb::RC localRegisterSize( const size_t size );
+
+		template< typename T >
+		static inline grb::RC get( const size_t src_pid, T &src, T &dst );
+
+		template<
+			grb::Descriptor descr,
+			grb::Backend backend,
+			typename T,
+			typename Coords
+			>
+		static inline grb::RC get( const size_t src_pid, const grb::Vector< T, backend, Coords > &src, grb::Vector< T, backend, Coords > &dst );
+
+		template< typename T >
+		static inline grb::RC put( const T &src, const size_t dst_pid, T &dst );
+
+		template<
+			grb::Descriptor descr,
+			grb::Backend backend,
+			typename T,
+			typename Coords
+			>
+		static inline grb::RC put( const grb::Vector< T, backend, Coords > &src, const size_t dst_pid, grb::Vector< T, backend, Coords > &dst );
+	}; // end class ``rdma''
+
+} // namespace grb
+
+#endif // end _H_GRB_BASE_SPMD
+