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+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __INCLUDE_RTE_TABLE_LPM_H__
+#define __INCLUDE_RTE_TABLE_LPM_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @file
+ * RTE Table LPM for IPv4
+ *
+ * This table uses the Longest Prefix Match (LPM) algorithm to uniquely
+ * associate data to lookup keys.
+ *
+ * Use-case: IP routing table. Routes that are added to the table associate a
+ * next hop to an IP prefix. The IP prefix is specified as IP address and depth
+ * and cover for a multitude of lookup keys (i.e. destination IP addresses)
+ * that all share the same data (i.e. next hop). The next hop information
+ * typically contains the output interface ID, the IP address of the next hop
+ * station (which is part of the same IP network the output interface is
+ * connected to) and other flags and counters.
+ *
+ * The LPM primitive only allows associating an 8-bit number (next hop ID) to
+ * an IP prefix, while a routing table can potentially contain thousands of
+ * routes or even more. This means that the same next hop ID (and next hop
+ * information) has to be shared by multiple routes, which makes sense, as
+ * multiple remote networks could be reached through the same next hop.
+ * Therefore, when a route is added or updated, the LPM table has to check
+ * whether the same next hop is already in use before using a new next hop ID
+ * for this route.
+ *
+ * The comparison between different next hops is done for the first
+ * “entry_unique_size” bytes of the next hop information (configurable
+ * parameter), which have to uniquely identify the next hop, therefore the user
+ * has to carefully manage the format of the LPM table entry (i.e.  the next
+ * hop information) so that any next hop data that changes value during
+ * run-time (e.g. counters) is placed outside of this area.
+ *
+ ***/
+
+#include <stdint.h>
+
+#include "rte_table.h"
+
+/** LPM table parameters */
+struct rte_table_lpm_params {
+	/** Table name */
+	const char *name;
+
+	/** Maximum number of LPM rules (i.e. IP routes) */
+	uint32_t n_rules;
+
+	/**< Number of tbl8s to allocate. */
+	uint32_t number_tbl8s;
+
+	/**< This field is currently unused. */
+	int flags;
+
+	/** Number of bytes at the start of the table entry that uniquely
+	identify the entry. Cannot be bigger than table entry size. */
+	uint32_t entry_unique_size;
+
+	/** Byte offset within input packet meta-data where lookup key (i.e.
+	the destination IP address) is located. */
+	uint32_t offset;
+};
+
+/** LPM table rule (i.e. route), specified as IP prefix. While the key used by
+the lookup operation is the destination IP address (read from the input packet
+meta-data), the entry add and entry delete operations work with LPM rules, with
+each rule covering for a multitude of lookup keys (destination IP addresses)
+that share the same data (next hop). */
+struct rte_table_lpm_key {
+	/** IP address */
+	uint32_t ip;
+
+	/** IP address depth. The most significant "depth" bits of the IP
+	address specify the network part of the IP address, while the rest of
+	the bits specify the host part of the address and are ignored for the
+	purpose of route specification. */
+	uint8_t depth;
+};
+
+/** LPM table operations */
+extern struct rte_table_ops rte_table_lpm_ops;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif