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-rw-r--r--lib/librte_lpm/rte_lpm.c971
1 files changed, 971 insertions, 0 deletions
diff --git a/lib/librte_lpm/rte_lpm.c b/lib/librte_lpm/rte_lpm.c
new file mode 100644
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+++ b/lib/librte_lpm/rte_lpm.c
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+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2012 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.
+ *
+ * version: DPDK.L.1.2.3-3
+ */
+
+#include <string.h>
+#include <stdint.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <errno.h>
+#include <sys/queue.h>
+
+#include <rte_log.h>
+#include <rte_branch_prediction.h>
+#include <rte_common.h>
+#include <rte_memory.h> /* for definition of CACHE_LINE_SIZE */
+#include <rte_malloc.h>
+#include <rte_memzone.h>
+#include <rte_tailq.h>
+#include <rte_eal.h>
+#include <rte_per_lcore.h>
+#include <rte_string_fns.h>
+#include <rte_errno.h>
+
+#include "rte_lpm.h"
+
+TAILQ_HEAD(rte_lpm_list, rte_lpm);
+
+/* global list of ring (used for debug/dump) */
+static struct rte_lpm_list *lpm_list;
+
+#define CHECK_LPM_LIST_CREATED() do { \
+ if (lpm_list == NULL) \
+ if ((lpm_list = RTE_TAILQ_RESERVE("RTE_LPM", rte_lpm_list)) == NULL){ \
+ rte_errno = E_RTE_NO_TAILQ; \
+ return NULL; \
+ } \
+} while (0)
+
+#define MAX_DEPTH_TBL24 24
+
+enum valid_flag {
+ INVALID = 0,
+ VALID
+};
+
+/* Macro to enable/disable run-time checks. */
+#if defined(RTE_LIBRTE_LPM_DEBUG)
+#include <rte_debug.h>
+#define VERIFY_DEPTH(depth) do { \
+ if ((depth == 0) || (depth > RTE_LPM_MAX_DEPTH)) \
+ rte_panic("LPM: Invalid depth (%u) at line %d", depth, __LINE__); \
+} while (0)
+#else
+#define VERIFY_DEPTH(depth)
+#endif
+
+/*
+ * Function Name: depth_to_mask
+ * Usage : Converts a given depth value to its corresponding mask value.
+ *
+ * depth (IN) : range = 1 - 32
+ * mask (OUT) : 32bit mask
+ */
+static uint32_t __attribute__((pure))
+depth_to_mask(uint8_t depth)
+{
+ VERIFY_DEPTH(depth);
+
+ /* To calculate a mask start with a 1 on the left hand side and right
+ * shift while populating the left hand side with 1's
+ */
+ return (int)0x80000000 >> (depth - 1);
+}
+
+/*
+ * Function Name: depth_to_range
+ * Usage : Converts given depth value to its corresponding range value.
+ *
+ * (IN) depth
+ * (OUT) mask
+ */
+static inline uint32_t __attribute__((pure))
+depth_to_range(uint8_t depth)
+{
+ VERIFY_DEPTH(depth);
+
+ /*
+ * Calculate tbl24 range. (Note: 2^depth = 1 << depth)
+ */
+ if (depth <= MAX_DEPTH_TBL24)
+ return 1 << (MAX_DEPTH_TBL24 - depth);
+
+ /* Else if depth is greater than 24 */
+ return (1 << (RTE_LPM_MAX_DEPTH - depth));
+}
+
+/*
+ * Find an existing lpm table and return a pointer to it.
+ */
+struct rte_lpm *
+rte_lpm_find_existing(const char *name)
+{
+ struct rte_lpm *l;
+
+ /* check that we have an initialised tail queue */
+ CHECK_LPM_LIST_CREATED();
+
+ TAILQ_FOREACH(l, lpm_list, next) {
+ if (strncmp(name, l->name, RTE_LPM_NAMESIZE) == 0)
+ break;
+ }
+
+ if (l == NULL)
+ rte_errno = ENOENT;
+
+ return l;
+}
+
+/*
+ * Function Name : rte_lpm_create
+ * Usage : Allocates memory for LPM object
+ *
+ * rte_lpm (RETURN)
+ */
+struct rte_lpm *
+rte_lpm_create(const char *name, int socket_id, int max_rules,
+ int mem_location)
+{
+ char mem_name[RTE_LPM_NAMESIZE];
+ struct rte_lpm *lpm = NULL;
+ uint32_t mem_size;
+
+ /* check that we have access to create things in shared memory. */
+ if (rte_eal_process_type() == RTE_PROC_SECONDARY){
+ rte_errno = E_RTE_SECONDARY;
+ return NULL;
+ }
+
+ /* check that we have an initialised tail queue */
+ CHECK_LPM_LIST_CREATED();
+
+ RTE_BUILD_BUG_ON(sizeof(struct rte_lpm_tbl24_entry) != 2);
+ RTE_BUILD_BUG_ON(sizeof(struct rte_lpm_tbl8_entry) != 2);
+
+ /* Check user arguments. */
+ if ((name == NULL) || (socket_id < -1) || (max_rules == 0) ||
+ (mem_location != RTE_LPM_HEAP &&
+ mem_location != RTE_LPM_MEMZONE)){
+ rte_errno = EINVAL;
+ return NULL;
+ }
+
+ rte_snprintf(mem_name, sizeof(mem_name), "LPM_%s", name);
+
+ /*
+ * Pad out max_rules so that each depth is given the same number of
+ * rules.
+ */
+ if (max_rules % RTE_LPM_MAX_DEPTH) {
+ max_rules += RTE_LPM_MAX_DEPTH -
+ (max_rules % RTE_LPM_MAX_DEPTH);
+ }
+
+ /* Determine the amount of memory to allocate. */
+ mem_size = sizeof(*lpm) + (sizeof(lpm->rules_tbl[0]) * max_rules);
+
+ /* Allocate memory to store the LPM data structures. */
+ if (mem_location == RTE_LPM_MEMZONE) {
+ const struct rte_memzone *mz;
+ uint32_t mz_flags = 0;
+
+ mz = rte_memzone_reserve(mem_name, mem_size, socket_id,
+ mz_flags);
+ if (mz == NULL) {
+ RTE_LOG(ERR, LPM, "LPM memzone creation failed\n");
+ return NULL;
+ }
+
+ memset(mz->addr, 0, mem_size);
+ lpm = (struct rte_lpm *) mz->addr;
+
+ }
+ else {
+ lpm = (struct rte_lpm *)rte_zmalloc(mem_name, mem_size,
+ CACHE_LINE_SIZE);
+ if (lpm == NULL) {
+ RTE_LOG(ERR, LPM, "LPM memory allocation failed\n");
+ return NULL;
+ }
+ }
+
+ /* Save user arguments. */
+ lpm->max_rules_per_depth = max_rules / RTE_LPM_MAX_DEPTH;
+ rte_snprintf(lpm->name, sizeof(lpm->name), "%s", name);
+ lpm->mem_location = mem_location;
+
+ TAILQ_INSERT_TAIL(lpm_list, lpm, next);
+
+ return lpm;
+}
+
+/*
+ * Function Name : free
+ * Usage: Deallocates memory for given LPM table.
+ */
+void
+rte_lpm_free(struct rte_lpm *lpm)
+{
+ /* Check user arguments. */
+ if (lpm == NULL)
+ return;
+
+ /* Note: Its is currently not possible to free a memzone. */
+ if (lpm->mem_location == RTE_LPM_HEAP){
+ TAILQ_REMOVE(lpm_list, lpm, next);
+ rte_free(lpm);
+ }
+}
+
+/*
+ * Function Name: rule_add
+ * Usage : Adds a rule to the rule table.
+ *
+ * NOTE: The rule table is split into 32 groups. Each group contains rules that
+ * apply to a specific prefix depth (i.e. group 1 contains rules that apply to
+ * prefixes with a depth of 1 etc.). In the following code (depth - 1) is used
+ * to refer to depth 1 because even though the depth range is 1 - 32, depths
+ * are stored in the rule table from 0 - 31.
+ * NOTE: Valid range for depth parameter is 1 .. 32 inclusive.
+ */
+static inline int32_t
+rule_add(struct rte_lpm *lpm, uint32_t ip_masked, uint8_t depth,
+ uint8_t next_hop)
+{
+ uint32_t rule_gindex, rule_index, last_rule;
+
+ VERIFY_DEPTH(depth);
+
+ /* rule_gindex stands for rule group index. */
+ rule_gindex = ((depth - 1) * lpm->max_rules_per_depth);
+ /* Initialise rule_index to point to start of rule group. */
+ rule_index = rule_gindex;
+ /* Last rule = Last used rule in this rule group. */
+ last_rule = rule_gindex + lpm->used_rules_at_depth[depth - 1];
+
+ /* Scan through rule group to see if rule already exists. */
+ for (rule_index = rule_gindex; rule_index < last_rule; rule_index++) {
+
+ /* If rule already exists update its next_hop and return. */
+ if (lpm->rules_tbl[rule_index].ip == ip_masked) {
+ lpm->rules_tbl[rule_index].next_hop = next_hop;
+
+ return rule_index;
+ }
+ }
+
+ /*
+ * If rule does not exist check if there is space to add a new rule to
+ * this rule group. If there is no space return error. */
+ if (lpm->used_rules_at_depth[depth - 1] == lpm->max_rules_per_depth) {
+ return -ENOSPC;
+ }
+
+ /* If there is space for the new rule add it. */
+ lpm->rules_tbl[rule_index].ip = ip_masked;
+ lpm->rules_tbl[rule_index].next_hop = next_hop;
+
+ /* Increment the used rules counter for this rule group. */
+ lpm->used_rules_at_depth[depth - 1]++;
+
+ return rule_index;
+}
+
+/*
+ * Function Name: rule_delete
+ * Usage : Delete a rule from the rule table.
+ * NOTE: Valid range for depth parameter is 1 .. 32 inclusive.
+ */
+static inline void
+rule_delete(struct rte_lpm *lpm, int32_t rule_index, uint8_t depth)
+{
+ uint32_t rule_gindex, last_rule_index;
+
+ VERIFY_DEPTH(depth);
+
+ rule_gindex = ((depth - 1) * lpm->max_rules_per_depth);
+ last_rule_index = rule_gindex +
+ (lpm->used_rules_at_depth[depth - 1]) - 1;
+ /*
+ * Overwrite redundant rule with last rule in group and decrement rule
+ * counter.
+ */
+ lpm->rules_tbl[rule_index] = lpm->rules_tbl[last_rule_index];
+ lpm->used_rules_at_depth[depth - 1]--;
+}
+
+
+/*
+ * Function Name: rule_find
+ * Usage : Finds a rule in rule table.
+ * NOTE: Valid range for depth parameter is 1 .. 32 inclusive.
+ */
+static inline int32_t
+rule_find(struct rte_lpm *lpm, uint32_t ip_masked, uint8_t depth)
+{
+ uint32_t rule_gindex, last_rule, rule_index;
+
+ VERIFY_DEPTH(depth);
+
+ rule_gindex = ((depth - 1) * lpm->max_rules_per_depth);
+ last_rule = rule_gindex + lpm->used_rules_at_depth[depth - 1];
+
+ /* Scan used rules at given depth to find rule. */
+ for (rule_index = rule_gindex; rule_index < last_rule; rule_index++) {
+ /* If rule is found return the rule index. */
+ if (lpm->rules_tbl[rule_index].ip == ip_masked)
+ return (rule_index);
+ }
+
+ /* If rule is not found return -E_RTE_NO_TAILQ. */
+ return -E_RTE_NO_TAILQ;
+}
+
+/*
+ * Function Name: tbl8_alloc
+ * Usage : Find, clean and allocate a tbl8.
+ */
+static inline int32_t
+tbl8_alloc(struct rte_lpm_tbl8_entry *tbl8)
+{
+ uint32_t tbl8_gindex; /* tbl8 group index. */
+ struct rte_lpm_tbl8_entry *tbl8_entry;
+
+ /* Scan through tbl8 to find a free (i.e. INVALID) tbl8 group. */
+ for (tbl8_gindex = 0; tbl8_gindex < RTE_LPM_TBL8_NUM_GROUPS;
+ tbl8_gindex++) {
+ tbl8_entry = &tbl8[tbl8_gindex *
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES];
+ /* If a free tbl8 group is found clean it and set as VALID. */
+ if (!tbl8_entry->valid_group) {
+ memset(&tbl8_entry[0], 0,
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES *
+ sizeof(tbl8_entry[0]));
+
+ tbl8_entry->valid_group = VALID;
+
+ /* Return group index for allocated tbl8 group. */
+ return tbl8_gindex;
+ }
+ }
+
+ /* If there are no tbl8 groups free then return error. */
+ return -ENOSPC;
+}
+
+static inline void
+tbl8_free(struct rte_lpm_tbl8_entry *tbl8, uint32_t tbl8_group_start)
+{
+ /* Set tbl8 group invalid*/
+ tbl8[tbl8_group_start].valid_group = INVALID;
+}
+
+static inline int32_t
+add_depth_small(struct rte_lpm *lpm, uint32_t ip, uint8_t depth,
+ uint8_t next_hop)
+{
+ uint32_t tbl24_index, tbl24_range, tbl8_index, tbl8_group_end, i, j;
+
+ /* Calculate the index into Table24. */
+ tbl24_index = ip >> 8;
+ tbl24_range = depth_to_range(depth);
+
+ for (i = tbl24_index; i < (tbl24_index + tbl24_range); i++) {
+ /*
+ * For invalid OR valid and non-extended tbl 24 entries set
+ * entry.
+ */
+ if (!lpm->tbl24[i].valid || (lpm->tbl24[i].ext_entry == 0 &&
+ lpm->tbl24[i].depth <= depth)) {
+
+ struct rte_lpm_tbl24_entry new_tbl24_entry = {
+ .valid = VALID,
+ .ext_entry = 0,
+ .depth = depth,
+ { .next_hop = next_hop, }
+ };
+
+ /* Setting tbl24 entry in one go to avoid race
+ * conditions */
+ lpm->tbl24[i] = new_tbl24_entry;
+
+ continue;
+ }
+
+ /* If tbl24 entry is valid and extended calculate the index
+ * into tbl8. */
+ tbl8_index = lpm->tbl24[tbl24_index].tbl8_gindex *
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ tbl8_group_end = tbl8_index + RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+
+ for (j = tbl8_index; j < tbl8_group_end; j++) {
+ if (!lpm->tbl8[j].valid ||
+ lpm->tbl8[j].depth <= depth) {
+ struct rte_lpm_tbl8_entry new_tbl8_entry = {
+ .valid = VALID,
+ .valid_group = VALID,
+ .depth = depth,
+ .next_hop = next_hop,
+ };
+
+ /*
+ * Setting tbl8 entry in one go to avoid race
+ * conditions
+ */
+ lpm->tbl8[j] = new_tbl8_entry;
+
+ continue;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static inline int32_t
+add_depth_big(struct rte_lpm *lpm, uint32_t ip_masked, uint8_t depth,
+ uint8_t next_hop)
+{
+ uint32_t tbl24_index;
+ int32_t tbl8_group_index, tbl8_group_start, tbl8_group_end, tbl8_index,
+ tbl8_range, i;
+
+ tbl24_index = (ip_masked >> 8);
+ tbl8_range = depth_to_range(depth);
+
+ if (!lpm->tbl24[tbl24_index].valid) {
+ /* Search for a free tbl8 group. */
+ tbl8_group_index = tbl8_alloc(lpm->tbl8);
+
+ /* Check tbl8 allocation was successful. */
+ if (tbl8_group_index < 0) {
+ return tbl8_group_index;
+ }
+
+ /* Find index into tbl8 and range. */
+ tbl8_index = (tbl8_group_index *
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES) +
+ (ip_masked & 0xFF);
+
+ /* Set tbl8 entry. */
+ for (i = tbl8_index; i < (tbl8_index + tbl8_range); i++) {
+ lpm->tbl8[i].depth = depth;
+ lpm->tbl8[i].next_hop = next_hop;
+ lpm->tbl8[i].valid = VALID;
+ }
+
+ /*
+ * Update tbl24 entry to point to new tbl8 entry. Note: The
+ * ext_flag and tbl8_index need to be updated simultaneously,
+ * so assign whole structure in one go
+ */
+
+ struct rte_lpm_tbl24_entry new_tbl24_entry = {
+ .valid = VALID,
+ .ext_entry = 1,
+ .depth = 0,
+ { .tbl8_gindex = (uint8_t)tbl8_group_index, }
+ };
+
+ lpm->tbl24[tbl24_index] = new_tbl24_entry;
+
+ }/* If valid entry but not extended calculate the index into Table8. */
+ else if (lpm->tbl24[tbl24_index].ext_entry == 0) {
+ /* Search for free tbl8 group. */
+ tbl8_group_index = tbl8_alloc(lpm->tbl8);
+
+ if (tbl8_group_index < 0) {
+ return tbl8_group_index;
+ }
+
+ tbl8_group_start = tbl8_group_index *
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ tbl8_group_end = tbl8_group_start +
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+
+ /* Populate new tbl8 with tbl24 value. */
+ for (i = tbl8_group_start; i < tbl8_group_end; i++) {
+ lpm->tbl8[i].valid = VALID;
+ lpm->tbl8[i].depth = lpm->tbl24[tbl24_index].depth;
+ lpm->tbl8[i].next_hop =
+ lpm->tbl24[tbl24_index].next_hop;
+ }
+
+ tbl8_index = tbl8_group_start + (ip_masked & 0xFF);
+
+ /* Insert new rule into the tbl8 entry. */
+ for (i = tbl8_index; i < tbl8_index + tbl8_range; i++) {
+ if (!lpm->tbl8[i].valid ||
+ lpm->tbl8[i].depth <= depth) {
+ lpm->tbl8[i].valid = VALID;
+ lpm->tbl8[i].depth = depth;
+ lpm->tbl8[i].next_hop = next_hop;
+
+ continue;
+ }
+ }
+
+ /*
+ * Update tbl24 entry to point to new tbl8 entry. Note: The
+ * ext_flag and tbl8_index need to be updated simultaneously,
+ * so assign whole structure in one go.
+ */
+
+ struct rte_lpm_tbl24_entry new_tbl24_entry = {
+ .valid = VALID,
+ .ext_entry = 1,
+ .depth = 0,
+ { .tbl8_gindex = (uint8_t)tbl8_group_index, }
+ };
+
+ lpm->tbl24[tbl24_index] = new_tbl24_entry;
+
+ }
+ else { /*
+ * If it is valid, extended entry calculate the index into tbl8.
+ */
+ tbl8_group_index = lpm->tbl24[tbl24_index].tbl8_gindex;
+ tbl8_group_start = tbl8_group_index *
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ tbl8_index = tbl8_group_start + (ip_masked & 0xFF);
+
+ for (i = tbl8_index; i < (tbl8_index + tbl8_range); i++) {
+
+ if (!lpm->tbl8[i].valid ||
+ lpm->tbl8[i].depth <= depth) {
+ struct rte_lpm_tbl8_entry new_tbl8_entry = {
+ .valid = VALID,
+ .depth = depth,
+ .next_hop = next_hop,
+ };
+
+ /*
+ * Setting tbl8 entry in one go to avoid race
+ * condition
+ */
+ lpm->tbl8[i] = new_tbl8_entry;
+
+ continue;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Function Name : rte_lpm_add
+ * Usage : Add a route
+ *
+ *(IN) lpm_handle,
+ *(IN) ip
+ *(IN) depth
+ *(IN) next_hop
+ */
+int
+rte_lpm_add(struct rte_lpm *lpm, uint32_t ip, uint8_t depth,
+ uint8_t next_hop)
+{
+ int32_t rule_index, status = 0;
+ uint32_t ip_masked = (ip & depth_to_mask(depth));
+
+ /* Check user arguments. */
+ if ((lpm == NULL) || (depth < 1) || (depth > RTE_LPM_MAX_DEPTH))
+ return -EINVAL;
+
+ /* Add the rule to the rule table. */
+ rule_index = rule_add(lpm, ip_masked, depth, next_hop);
+
+ /* If the is no space available for new rule return error. */
+ if (rule_index < 0) {
+ return rule_index;
+ }
+
+ if (depth <= MAX_DEPTH_TBL24) {
+ status = add_depth_small(lpm, ip_masked, depth, next_hop);
+ }
+ else { /* If depth > RTE_LPM_MAX_DEPTH_TBL24 */
+ status = add_depth_big(lpm, ip_masked, depth, next_hop);
+
+ /*
+ * If add fails due to exhaustion of tbl8 extensions delete
+ * rule that was added to rule table.
+ */
+ if (status < 0) {
+ rule_delete(lpm, rule_index, depth);
+
+ return status;
+ }
+ }
+
+ return 0;
+}
+
+static inline int32_t
+find_previous_rule(struct rte_lpm *lpm, uint32_t ip, uint8_t depth)
+{
+ int32_t rule_index;
+ uint32_t ip_masked;
+ uint8_t prev_depth;
+
+ for (prev_depth = (uint8_t)(depth - 1); prev_depth > 0; prev_depth--) {
+ ip_masked = ip & depth_to_mask(prev_depth);
+
+ rule_index = rule_find(lpm, ip_masked, prev_depth);
+
+ if (rule_index >= 0)
+ return rule_index;
+ }
+
+ return -1;
+}
+
+static inline int32_t
+delete_depth_small(struct rte_lpm *lpm, uint32_t ip_masked,
+ uint8_t depth, int32_t sub_rule_index)
+{
+ uint32_t tbl24_range, tbl24_index, tbl8_group_index, tbl8_index, i, j;
+ uint8_t new_depth;
+
+ /* Calculate the range and index into Table24. */
+ tbl24_range = depth_to_range(depth);
+ tbl24_index = (ip_masked >> 8);
+
+ /*
+ * Firstly check the sub_rule_index. A -1 indicates no replacement rule
+ * and a positive number indicates a sub_rule_index.
+ */
+ if (sub_rule_index < 0) {
+ /*
+ * If no replacement rule exists then invalidate entries
+ * associated with this rule.
+ */
+ for (i = tbl24_index; i < (tbl24_index + tbl24_range); i++) {
+ if (lpm->tbl24[i].ext_entry == 0 &&
+ lpm->tbl24[i].depth <= depth ) {
+ lpm->tbl24[i].valid = INVALID;
+ }
+ else {
+ /*
+ * If TBL24 entry is extended, then there has
+ * to be a rule with depth >= 25 in the
+ * associated TBL8 group.
+ */
+ tbl8_group_index = lpm->tbl24[i].tbl8_gindex;
+ tbl8_index = tbl8_group_index *
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+
+ for (j = tbl8_index; j < (tbl8_index +
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES); j++) {
+
+ if (lpm->tbl8[j].depth <= depth)
+ lpm->tbl8[j].valid = INVALID;
+ }
+ }
+ }
+ }
+ else {
+ /*
+ * If a replacement rule exists then modify entries
+ * associated with this rule.
+ */
+
+ /* Calculate depth of sub_rule. */
+ new_depth = (uint8_t) (sub_rule_index /
+ lpm->max_rules_per_depth);
+
+ struct rte_lpm_tbl24_entry new_tbl24_entry = {
+ .valid = VALID,
+ .ext_entry = 0,
+ .depth = new_depth,
+ {.next_hop = lpm->rules_tbl[sub_rule_index].next_hop,}
+ };
+
+ struct rte_lpm_tbl8_entry new_tbl8_entry = {
+ .valid = VALID,
+ .depth = new_depth,
+ .next_hop = lpm->rules_tbl
+ [sub_rule_index].next_hop,
+ };
+
+ for (i = tbl24_index; i < (tbl24_index + tbl24_range); i++) {
+
+ if (lpm->tbl24[i].ext_entry == 0 &&
+ lpm->tbl24[i].depth <= depth ) {
+ lpm->tbl24[i] = new_tbl24_entry;
+ }
+ else {
+ /*
+ * If TBL24 entry is extended, then there has
+ * to be a rule with depth >= 25 in the
+ * associated TBL8 group.
+ */
+
+ tbl8_group_index = lpm->tbl24[i].tbl8_gindex;
+ tbl8_index = tbl8_group_index *
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+
+ for (j = tbl8_index; j < (tbl8_index +
+ RTE_LPM_TBL8_GROUP_NUM_ENTRIES); j++) {
+
+ if (lpm->tbl8[j].depth <= depth)
+ lpm->tbl8[j] = new_tbl8_entry;
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Function Name: tbl8_recycle_check
+ * Usage : Checks if table 8 group can be recycled.
+ *
+ * Return of -EEXIST means tbl8 is in use and thus can not be recycled.
+ * Return of -EINVAL means tbl8 is empty and thus can be recycled
+ * Return of value > -1 means tbl8 is in use but has all the same values and
+ * thus can be recycled
+ */
+static inline int32_t
+tbl8_recycle_check(struct rte_lpm_tbl8_entry *tbl8, uint32_t tbl8_group_start)
+{
+ uint32_t tbl8_group_end, i;
+ tbl8_group_end = tbl8_group_start + RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+
+ /*
+ * Check the first entry of the given tbl8. If it is invalid we know
+ * this tbl8 does not contain any rule with a depth < RTE_LPM_MAX_DEPTH
+ * (As they would affect all entries in a tbl8) and thus this table
+ * can not be recycled.
+ */
+ if (tbl8[tbl8_group_start].valid) {
+ /*
+ * If first entry is valid check if the depth is less than 24
+ * and if so check the rest of the entries to verify that they
+ * are all of this depth.
+ */
+ if (tbl8[tbl8_group_start].depth < MAX_DEPTH_TBL24) {
+ for (i = (tbl8_group_start + 1); i < tbl8_group_end;
+ i++) {
+
+ if (tbl8[i].depth !=
+ tbl8[tbl8_group_start].depth) {
+
+ return -EEXIST;
+ }
+ }
+ /* If all entries are the same return the tb8 index */
+ return tbl8_group_start;
+ }
+
+ return -EEXIST;
+ }
+ /*
+ * If the first entry is invalid check if the rest of the entries in
+ * the tbl8 are invalid.
+ */
+ for (i = (tbl8_group_start + 1); i < tbl8_group_end; i++) {
+ if (tbl8[i].valid)
+ return -EEXIST;
+ }
+ /* If no valid entries are found then return -EINVAL. */
+ return -EINVAL;
+}
+
+static inline int32_t
+delete_depth_big(struct rte_lpm *lpm, uint32_t ip_masked,
+ uint8_t depth, int32_t sub_rule_index)
+{
+ uint32_t tbl24_index, tbl8_group_index, tbl8_group_start, tbl8_index,
+ tbl8_range, i;
+ uint8_t new_depth;
+ int32_t tbl8_recycle_index;
+
+ /*
+ * Calculate the index into tbl24 and range. Note: All depths larger
+ * than MAX_DEPTH_TBL24 are associated with only one tbl24 entry.
+ */
+ tbl24_index = ip_masked >> 8;
+
+ /* Calculate the index into tbl8 and range. */
+ tbl8_group_index = lpm->tbl24[tbl24_index].tbl8_gindex;
+ tbl8_group_start = tbl8_group_index * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
+ tbl8_index = tbl8_group_start + (ip_masked & 0xFF);
+ tbl8_range = depth_to_range(depth);
+
+ if (sub_rule_index < 0) {
+ /*
+ * Loop through the range of entries on tbl8 for which the
+ * rule_to_delete must be removed or modified.
+ */
+ for (i = tbl8_index; i < (tbl8_index + tbl8_range); i++) {
+ if (lpm->tbl8[i].depth <= depth)
+ lpm->tbl8[i].valid = INVALID;
+ }
+ }
+ else {
+ new_depth = (uint8_t)(sub_rule_index /
+ lpm->max_rules_per_depth);
+
+ /* Set new tbl8 entry. */
+ struct rte_lpm_tbl8_entry new_tbl8_entry = {
+ .valid = VALID,
+ .depth = new_depth,
+ .next_hop = lpm->rules_tbl[sub_rule_index].next_hop,
+ };
+
+ /*
+ * Loop through the range of entries on tbl8 for which the
+ * rule_to_delete must be modified.
+ */
+ for (i = tbl8_index; i < (tbl8_index + tbl8_range); i++) {
+ if (lpm->tbl8[i].depth <= depth)
+ lpm->tbl8[i] = new_tbl8_entry;
+ }
+ }
+
+ /*
+ * Check if there are any valid entries in this tbl8 group. If all
+ * tbl8 entries are invalid we can free the tbl8 and invalidate the
+ * associated tbl24 entry.
+ */
+
+ tbl8_recycle_index = tbl8_recycle_check(lpm->tbl8, tbl8_group_start);
+
+ if (tbl8_recycle_index == -EINVAL){
+ /* Set tbl24 before freeing tbl8 to avoid race condition. */
+ lpm->tbl24[tbl24_index].valid = 0;
+ tbl8_free(lpm->tbl8, tbl8_group_start);
+ }
+ else if (tbl8_recycle_index > -1) {
+ /* Update tbl24 entry. */
+ struct rte_lpm_tbl24_entry new_tbl24_entry = {
+ .valid = VALID,
+ .ext_entry = 0,
+ .depth = lpm->tbl8[tbl8_recycle_index].depth,
+ { .next_hop = lpm->tbl8[tbl8_recycle_index].next_hop, }
+ };
+
+ /* Set tbl24 before freeing tbl8 to avoid race condition. */
+ lpm->tbl24[tbl24_index] = new_tbl24_entry;
+ tbl8_free(lpm->tbl8, tbl8_group_start);
+ }
+
+ return 0;
+}
+
+/*
+ * Function Name: rte_lpm_delete
+ * Usage : Deletes a rule
+ *
+ *(IN) lpm_handle,
+ *(IN) ip
+ *(IN) depth
+ */
+int
+rte_lpm_delete(struct rte_lpm *lpm, uint32_t ip, uint8_t depth)
+{
+ int32_t rule_to_delete_index, sub_rule_index;
+ uint32_t ip_masked;
+ /*
+ * Check input arguments. Note: IP must be a positive integer of 32
+ * bits in length therefore it need not be checked.
+ */
+ if ((lpm == NULL) || (depth < 1) || (depth > RTE_LPM_MAX_DEPTH)) {
+ return -EINVAL;
+ }
+
+ ip_masked = ip & depth_to_mask(depth);
+
+ /*
+ * Find the index of the input rule, that needs to be deleted, in the
+ * rule table.
+ */
+ rule_to_delete_index = rule_find(lpm, ip_masked, depth);
+
+ /*
+ * Check if rule_to_delete_index was found. If no rule was found the
+ * function rule_find returns -E_RTE_NO_TAILQ.
+ */
+ if (rule_to_delete_index < 0)
+ return -E_RTE_NO_TAILQ;
+
+ /* Delete the rule from the rule table. */
+ rule_delete(lpm, rule_to_delete_index, depth);
+
+ /*
+ * Find rule to replace the rule_to_delete. If there is no rule to
+ * replace the rule_to_delete we return -1 and invalidate the table
+ * entries associated with this rule.
+ */
+ sub_rule_index = find_previous_rule(lpm, ip, depth);
+
+ /*
+ * If the input depth value is less than 25 use function
+ * delete_depth_small otherwise use delete_depth_big.
+ */
+ if (depth <= MAX_DEPTH_TBL24) {
+ return delete_depth_small(lpm, ip_masked, depth,
+ sub_rule_index);
+ }
+ else { /* If depth > MAX_DEPTH_TBL24 */
+ return delete_depth_big(lpm, ip_masked, depth, sub_rule_index);
+ }
+}
+
+/*
+ * Function Name: rte_lpm_delete_all
+ * Usage : Delete all rules from the LPM table.
+ *
+ *(IN) lpm_handle
+ */
+void
+rte_lpm_delete_all(struct rte_lpm *lpm)
+{
+ /* Zero used rules counter. */
+ memset(lpm->used_rules_at_depth, 0, sizeof(lpm->used_rules_at_depth));
+
+ /* Zero tbl24. */
+ memset(lpm->tbl24, 0, sizeof(lpm->tbl24));
+
+ /* Zero tbl8. */
+ memset(lpm->tbl8, 0, sizeof(lpm->tbl8));
+
+ /* Delete all rules form the rules table. */
+ memset(lpm->rules_tbl, 0, sizeof(lpm->rules_tbl[0]) *
+ (lpm->max_rules_per_depth * RTE_LPM_MAX_DEPTH));
+}
+