freebsd-dev/sys/contrib/dpdk_rte_lpm/rte_lpm6.c
Alexander V. Chernikov 537d134373 Bring DPDK route lookups to FreeBSD.
This change introduces loadable fib lookup modules based on
 DPDK rte_lpm lib targeted for high-speed lookups in large-scale tables.
It is based on the lookup framework described in D27401.

IPv4 module is called dpdk_lpm4. It wraps around rte_lpm [1] library.
This library implements variation of DIR24-8 [2] lookup algorithm.
Module provide lockless route lookups and in-place incremental updates,
 allowing for good RIB performance.

IPv6 module is called dpdk_lpm6. It wraps around rte_lpm6 [3] library.
Implementation can be seen as multi-bit trie where the stride or number of bits
 inspected on each level varies from level to level.
It can vary from 1 to 14 memory accesses, with 5 being the average value
 for the lengths that are most commonly used in IPv6.
Module provide lockless route lookups for global unicast addresses
 and in-place incremental updates, allowing for good RIB performance.

Implementation details:
* wrapper code lives in `sys/contrib/dpdk_rte_lpm/dpdk_lpm[6].c`.
* rte_lpm[6] implementation contains both RIB and FIB code.
 . RIB ("rule_") code, backed by array of hash tables part has been commented out,
 as base radix already provides all the necessary primitives.
* link-local lookups are currently implemented as base radix lookup.
 This part should be converted to something like read-only radix trie.

Usage detail:
Compile kernel with option FIB_ALGO and load dpdk_lpm4/dpdk_lpm6
 module at any time. They will be picked up automatically when
 amount of routes raises to several thousand.

[1]: https://doc.dpdk.org/guides/prog_guide/lpm_lib.html
[2]: http://yuba.stanford.edu/~nickm/papers/Infocom98_lookup.pdf
[3]: https://doc.dpdk.org/guides/prog_guide/lpm6_lib.html

Differential Revision: https://reviews.freebsd.org/D27412
2021-01-09 12:41:04 +00:00

1416 lines
34 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2010-2014 Intel Corporation
*/
#include <sys/param.h>
#include <sys/ctype.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/kernel.h>
//#include <netinet6/rte_tailq.h>
int errno = 0, rte_errno = 0;
#include "rte_shim.h"
#include "rte_lpm6.h"
#define RTE_LPM6_TBL24_NUM_ENTRIES (1 << 24)
#define RTE_LPM6_TBL8_GROUP_NUM_ENTRIES 256
#define RTE_LPM6_TBL8_MAX_NUM_GROUPS (1 << 21)
#define RTE_LPM6_VALID_EXT_ENTRY_BITMASK 0xA0000000
#define RTE_LPM6_LOOKUP_SUCCESS 0x20000000
#define RTE_LPM6_TBL8_BITMASK 0x001FFFFF
#define ADD_FIRST_BYTE 3
#define LOOKUP_FIRST_BYTE 4
#define BYTE_SIZE 8
#define BYTES2_SIZE 16
#define RULE_HASH_TABLE_EXTRA_SPACE 64
#define TBL24_IND UINT32_MAX
#define lpm6_tbl8_gindex next_hop
/** Flags for setting an entry as valid/invalid. */
enum valid_flag {
INVALID = 0,
VALID
};
#if 0
TAILQ_HEAD(rte_lpm6_list, rte_tailq_entry);
static struct rte_tailq_elem rte_lpm6_tailq = {
.name = "RTE_LPM6",
};
EAL_REGISTER_TAILQ(rte_lpm6_tailq)
#endif
/** Tbl entry structure. It is the same for both tbl24 and tbl8 */
struct rte_lpm6_tbl_entry {
uint32_t next_hop: 21; /**< Next hop / next table to be checked. */
uint32_t depth :8; /**< Rule depth. */
/* Flags. */
uint32_t valid :1; /**< Validation flag. */
uint32_t valid_group :1; /**< Group validation flag. */
uint32_t ext_entry :1; /**< External entry. */
};
/** Rules tbl entry structure. */
struct rte_lpm6_rule {
uint8_t ip[RTE_LPM6_IPV6_ADDR_SIZE]; /**< Rule IP address. */
uint32_t next_hop; /**< Rule next hop. */
uint8_t depth; /**< Rule depth. */
};
/** Rules tbl entry key. */
struct rte_lpm6_rule_key {
uint8_t ip[RTE_LPM6_IPV6_ADDR_SIZE]; /**< Rule IP address. */
uint8_t depth; /**< Rule depth. */
};
/* Header of tbl8 */
struct rte_lpm_tbl8_hdr {
uint32_t owner_tbl_ind; /**< owner table: TBL24_IND if owner is tbl24,
* otherwise index of tbl8
*/
uint32_t owner_entry_ind; /**< index of the owner table entry where
* pointer to the tbl8 is stored
*/
uint32_t ref_cnt; /**< table reference counter */
};
/** LPM6 structure. */
struct rte_lpm6 {
struct rte_lpm6_external ext; /* Storage used by the algo wrapper */
/* LPM metadata. */
char name[RTE_LPM6_NAMESIZE]; /**< Name of the lpm. */
uint32_t max_rules; /**< Max number of rules. */
uint32_t used_rules; /**< Used rules so far. */
uint32_t number_tbl8s; /**< Number of tbl8s to allocate. */
/* LPM Tables. */
//struct rte_hash *rules_tbl; /**< LPM rules. */
struct rte_lpm6_tbl_entry tbl24[RTE_LPM6_TBL24_NUM_ENTRIES]
__rte_cache_aligned; /**< LPM tbl24 table. */
uint32_t *tbl8_pool; /**< pool of indexes of free tbl8s */
uint32_t tbl8_pool_pos; /**< current position in the tbl8 pool */
struct rte_lpm_tbl8_hdr *tbl8_hdrs; /* array of tbl8 headers */
struct rte_lpm6_tbl_entry tbl8[0]
__rte_cache_aligned; /**< LPM tbl8 table. */
};
/*
* Takes an array of uint8_t (IPv6 address) and masks it using the depth.
* It leaves untouched one bit per unit in the depth variable
* and set the rest to 0.
*/
static inline void
ip6_mask_addr(uint8_t *ip, uint8_t depth)
{
int16_t part_depth, mask;
int i;
part_depth = depth;
for (i = 0; i < RTE_LPM6_IPV6_ADDR_SIZE; i++) {
if (part_depth < BYTE_SIZE && part_depth >= 0) {
mask = (uint16_t)(~(UINT8_MAX >> part_depth));
ip[i] = (uint8_t)(ip[i] & mask);
} else if (part_depth < 0)
ip[i] = 0;
part_depth -= BYTE_SIZE;
}
}
/* copy ipv6 address */
static inline void
ip6_copy_addr(uint8_t *dst, const uint8_t *src)
{
rte_memcpy(dst, src, RTE_LPM6_IPV6_ADDR_SIZE);
}
#if 0
/*
* LPM6 rule hash function
*
* It's used as a hash function for the rte_hash
* containing rules
*/
static inline uint32_t
rule_hash(const void *data, __rte_unused uint32_t data_len,
uint32_t init_val)
{
return rte_jhash(data, sizeof(struct rte_lpm6_rule_key), init_val);
}
#endif
/*
* Init pool of free tbl8 indexes
*/
static void
tbl8_pool_init(struct rte_lpm6 *lpm)
{
uint32_t i;
/* put entire range of indexes to the tbl8 pool */
for (i = 0; i < lpm->number_tbl8s; i++)
lpm->tbl8_pool[i] = i;
lpm->tbl8_pool_pos = 0;
}
/*
* Get an index of a free tbl8 from the pool
*/
static inline uint32_t
tbl8_get(struct rte_lpm6 *lpm, uint32_t *tbl8_ind)
{
if (lpm->tbl8_pool_pos == lpm->number_tbl8s)
/* no more free tbl8 */
return -ENOSPC;
/* next index */
*tbl8_ind = lpm->tbl8_pool[lpm->tbl8_pool_pos++];
return 0;
}
/*
* Put an index of a free tbl8 back to the pool
*/
static inline uint32_t
tbl8_put(struct rte_lpm6 *lpm, uint32_t tbl8_ind)
{
if (lpm->tbl8_pool_pos == 0)
/* pool is full */
return -ENOSPC;
lpm->tbl8_pool[--lpm->tbl8_pool_pos] = tbl8_ind;
return 0;
}
/*
* Returns number of tbl8s available in the pool
*/
static inline uint32_t
tbl8_available(struct rte_lpm6 *lpm)
{
return lpm->number_tbl8s - lpm->tbl8_pool_pos;
}
#if 0
/*
* Init a rule key.
* note that ip must be already masked
*/
static inline void
rule_key_init(struct rte_lpm6_rule_key *key, uint8_t *ip, uint8_t depth)
{
ip6_copy_addr(key->ip, ip);
key->depth = depth;
}
/*
* Rebuild the entire LPM tree by reinserting all rules
*/
static void
rebuild_lpm(struct rte_lpm6 *lpm)
{
uint64_t next_hop;
struct rte_lpm6_rule_key *rule_key;
uint32_t iter = 0;
while (rte_hash_iterate(lpm->rules_tbl, (void *) &rule_key,
(void **) &next_hop, &iter) >= 0)
rte_lpm6_add(lpm, rule_key->ip, rule_key->depth,
(uint32_t) next_hop);
}
#endif
/*
* Allocates memory for LPM object
*/
struct rte_lpm6 *
rte_lpm6_create(const char *name, int socket_id,
const struct rte_lpm6_config *config)
{
char mem_name[RTE_LPM6_NAMESIZE];
struct rte_lpm6 *lpm = NULL;
//struct rte_tailq_entry *te;
uint64_t mem_size;
//struct rte_lpm6_list *lpm_list;
//struct rte_hash *rules_tbl = NULL;
uint32_t *tbl8_pool = NULL;
struct rte_lpm_tbl8_hdr *tbl8_hdrs = NULL;
//lpm_list = RTE_TAILQ_CAST(rte_lpm6_tailq.head, rte_lpm6_list);
RTE_BUILD_BUG_ON(sizeof(struct rte_lpm6_tbl_entry) != sizeof(uint32_t));
/* Check user arguments. */
if ((name == NULL) || (socket_id < -1) || (config == NULL) ||
config->number_tbl8s > RTE_LPM6_TBL8_MAX_NUM_GROUPS) {
rte_errno = EINVAL;
return NULL;
}
#if 0
/* create rules hash table */
snprintf(mem_name, sizeof(mem_name), "LRH_%s", name);
struct rte_hash_parameters rule_hash_tbl_params = {
.entries = config->max_rules * 1.2 +
RULE_HASH_TABLE_EXTRA_SPACE,
.key_len = sizeof(struct rte_lpm6_rule_key),
.hash_func = rule_hash,
.hash_func_init_val = 0,
.name = mem_name,
.reserved = 0,
.socket_id = socket_id,
.extra_flag = 0
};
rules_tbl = rte_hash_create(&rule_hash_tbl_params);
if (rules_tbl == NULL) {
RTE_LOG(ERR, LPM, "LPM rules hash table allocation failed: %s (%d)",
rte_strerror(rte_errno), rte_errno);
goto fail_wo_unlock;
}
#endif
/* allocate tbl8 indexes pool */
tbl8_pool = rte_malloc(NULL,
sizeof(uint32_t) * config->number_tbl8s,
RTE_CACHE_LINE_SIZE);
if (tbl8_pool == NULL) {
RTE_LOG(ERR, LPM, "LPM tbl8 pool allocation failed: %s (%d)",
rte_strerror(rte_errno), rte_errno);
rte_errno = ENOMEM;
goto fail_wo_unlock;
}
/* allocate tbl8 headers */
tbl8_hdrs = rte_malloc(NULL,
sizeof(struct rte_lpm_tbl8_hdr) * config->number_tbl8s,
RTE_CACHE_LINE_SIZE);
if (tbl8_hdrs == NULL) {
RTE_LOG(ERR, LPM, "LPM tbl8 headers allocation failed: %s (%d)",
rte_strerror(rte_errno), rte_errno);
rte_errno = ENOMEM;
goto fail_wo_unlock;
}
snprintf(mem_name, sizeof(mem_name), "LPM_%s", name);
/* Determine the amount of memory to allocate. */
mem_size = sizeof(*lpm) + (sizeof(lpm->tbl8[0]) *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES * config->number_tbl8s);
#if 0
rte_mcfg_tailq_write_lock();
/* Guarantee there's no existing */
TAILQ_FOREACH(te, lpm_list, next) {
lpm = (struct rte_lpm6 *) te->data;
if (strncmp(name, lpm->name, RTE_LPM6_NAMESIZE) == 0)
break;
}
lpm = NULL;
if (te != NULL) {
rte_errno = EEXIST;
goto fail;
}
/* allocate tailq entry */
te = rte_zmalloc("LPM6_TAILQ_ENTRY", sizeof(*te), 0);
if (te == NULL) {
RTE_LOG(ERR, LPM, "Failed to allocate tailq entry!\n");
rte_errno = ENOMEM;
goto fail;
}
#endif
/* Allocate memory to store the LPM data structures. */
lpm = rte_zmalloc_socket(mem_name, (size_t)mem_size,
RTE_CACHE_LINE_SIZE, socket_id);
if (lpm == NULL) {
RTE_LOG(ERR, LPM, "LPM memory allocation failed\n");
//rte_free(te);
rte_errno = ENOMEM;
goto fail;
}
/* Save user arguments. */
//lpm->max_rules = config->max_rules;
lpm->number_tbl8s = config->number_tbl8s;
strlcpy(lpm->name, name, sizeof(lpm->name));
//lpm->rules_tbl = rules_tbl;
lpm->tbl8_pool = tbl8_pool;
lpm->tbl8_hdrs = tbl8_hdrs;
/* init the stack */
tbl8_pool_init(lpm);
//te->data = (void *) lpm;
//TAILQ_INSERT_TAIL(lpm_list, te, next);
rte_mcfg_tailq_write_unlock();
return lpm;
fail:
rte_mcfg_tailq_write_unlock();
fail_wo_unlock:
rte_free(tbl8_hdrs);
rte_free(tbl8_pool);
//rte_hash_free(rules_tbl);
return NULL;
}
#if 0
/*
* Find an existing lpm table and return a pointer to it.
*/
struct rte_lpm6 *
rte_lpm6_find_existing(const char *name)
{
struct rte_lpm6 *l = NULL;
struct rte_tailq_entry *te;
struct rte_lpm6_list *lpm_list;
lpm_list = RTE_TAILQ_CAST(rte_lpm6_tailq.head, rte_lpm6_list);
rte_mcfg_tailq_read_lock();
TAILQ_FOREACH(te, lpm_list, next) {
l = (struct rte_lpm6 *) te->data;
if (strncmp(name, l->name, RTE_LPM6_NAMESIZE) == 0)
break;
}
rte_mcfg_tailq_read_unlock();
if (te == NULL) {
rte_errno = ENOENT;
return NULL;
}
return l;
}
#endif
/*
* Deallocates memory for given LPM table.
*/
void
rte_lpm6_free(struct rte_lpm6 *lpm)
{
#if 0
struct rte_lpm6_list *lpm_list;
struct rte_tailq_entry *te;
/* Check user arguments. */
if (lpm == NULL)
return;
lpm_list = RTE_TAILQ_CAST(rte_lpm6_tailq.head, rte_lpm6_list);
rte_mcfg_tailq_write_lock();
/* find our tailq entry */
TAILQ_FOREACH(te, lpm_list, next) {
if (te->data == (void *) lpm)
break;
}
if (te != NULL)
TAILQ_REMOVE(lpm_list, te, next);
rte_mcfg_tailq_write_unlock();
#endif
rte_free(lpm->tbl8_hdrs);
rte_free(lpm->tbl8_pool);
//rte_hash_free(lpm->rules_tbl);
rte_free(lpm);
//rte_free(te);
}
#if 0
/* Find a rule */
static inline int
rule_find_with_key(struct rte_lpm6 *lpm,
const struct rte_lpm6_rule_key *rule_key,
uint32_t *next_hop)
{
uint64_t hash_val;
int ret;
/* lookup for a rule */
ret = rte_hash_lookup_data(lpm->rules_tbl, (const void *) rule_key,
(void **) &hash_val);
if (ret >= 0) {
*next_hop = (uint32_t) hash_val;
return 1;
}
return 0;
}
/* Find a rule */
static int
rule_find(struct rte_lpm6 *lpm, uint8_t *ip, uint8_t depth,
uint32_t *next_hop)
{
struct rte_lpm6_rule_key rule_key;
/* init a rule key */
rule_key_init(&rule_key, ip, depth);
return rule_find_with_key(lpm, &rule_key, next_hop);
}
/*
* Checks if a rule already exists in the rules table and updates
* the nexthop if so. Otherwise it adds a new rule if enough space is available.
*
* Returns:
* 0 - next hop of existed rule is updated
* 1 - new rule successfully added
* <0 - error
*/
static inline int
rule_add(struct rte_lpm6 *lpm, uint8_t *ip, uint8_t depth, uint32_t next_hop)
{
int ret, rule_exist;
struct rte_lpm6_rule_key rule_key;
uint32_t unused;
/* init a rule key */
rule_key_init(&rule_key, ip, depth);
/* Scan through rule list to see if rule already exists. */
rule_exist = rule_find_with_key(lpm, &rule_key, &unused);
/*
* 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 (!rule_exist && lpm->used_rules == lpm->max_rules)
return -ENOSPC;
/* add the rule or update rules next hop */
ret = rte_hash_add_key_data(lpm->rules_tbl, &rule_key,
(void *)(uintptr_t) next_hop);
if (ret < 0)
return ret;
/* Increment the used rules counter for this rule group. */
if (!rule_exist) {
lpm->used_rules++;
return 1;
}
return 0;
}
#endif
/*
* Function that expands a rule across the data structure when a less-generic
* one has been added before. It assures that every possible combination of bits
* in the IP address returns a match.
*/
static void
expand_rule(struct rte_lpm6 *lpm, uint32_t tbl8_gindex, uint8_t old_depth,
uint8_t new_depth, uint32_t next_hop, uint8_t valid)
{
uint32_t tbl8_group_end, tbl8_gindex_next, j;
tbl8_group_end = tbl8_gindex + RTE_LPM6_TBL8_GROUP_NUM_ENTRIES;
struct rte_lpm6_tbl_entry new_tbl8_entry = {
.valid = valid,
.valid_group = valid,
.depth = new_depth,
.next_hop = next_hop,
.ext_entry = 0,
};
for (j = tbl8_gindex; j < tbl8_group_end; j++) {
if (!lpm->tbl8[j].valid || (lpm->tbl8[j].ext_entry == 0
&& lpm->tbl8[j].depth <= old_depth)) {
lpm->tbl8[j] = new_tbl8_entry;
} else if (lpm->tbl8[j].ext_entry == 1) {
tbl8_gindex_next = lpm->tbl8[j].lpm6_tbl8_gindex
* RTE_LPM6_TBL8_GROUP_NUM_ENTRIES;
expand_rule(lpm, tbl8_gindex_next, old_depth, new_depth,
next_hop, valid);
}
}
}
/*
* Init a tbl8 header
*/
static inline void
init_tbl8_header(struct rte_lpm6 *lpm, uint32_t tbl_ind,
uint32_t owner_tbl_ind, uint32_t owner_entry_ind)
{
struct rte_lpm_tbl8_hdr *tbl_hdr = &lpm->tbl8_hdrs[tbl_ind];
tbl_hdr->owner_tbl_ind = owner_tbl_ind;
tbl_hdr->owner_entry_ind = owner_entry_ind;
tbl_hdr->ref_cnt = 0;
}
/*
* Calculate index to the table based on the number and position
* of the bytes being inspected in this step.
*/
static uint32_t
get_bitshift(const uint8_t *ip, uint8_t first_byte, uint8_t bytes)
{
uint32_t entry_ind, i;
int8_t bitshift;
entry_ind = 0;
for (i = first_byte; i < (uint32_t)(first_byte + bytes); i++) {
bitshift = (int8_t)((bytes - i)*BYTE_SIZE);
if (bitshift < 0)
bitshift = 0;
entry_ind = entry_ind | ip[i-1] << bitshift;
}
return entry_ind;
}
/*
* Simulate adding a new route to the LPM counting number
* of new tables that will be needed
*
* It returns 0 on success, or 1 if
* the process needs to be continued by calling the function again.
*/
static inline int
simulate_add_step(struct rte_lpm6 *lpm, struct rte_lpm6_tbl_entry *tbl,
struct rte_lpm6_tbl_entry **next_tbl, const uint8_t *ip,
uint8_t bytes, uint8_t first_byte, uint8_t depth,
uint32_t *need_tbl_nb)
{
uint32_t entry_ind;
uint8_t bits_covered;
uint32_t next_tbl_ind;
/*
* Calculate index to the table based on the number and position
* of the bytes being inspected in this step.
*/
entry_ind = get_bitshift(ip, first_byte, bytes);
/* Number of bits covered in this step */
bits_covered = (uint8_t)((bytes+first_byte-1)*BYTE_SIZE);
if (depth <= bits_covered) {
*need_tbl_nb = 0;
return 0;
}
if (tbl[entry_ind].valid == 0 || tbl[entry_ind].ext_entry == 0) {
/* from this point on a new table is needed on each level
* that is not covered yet
*/
depth -= bits_covered;
uint32_t cnt = depth >> 3; /* depth / BYTE_SIZE */
if (depth & 7) /* 0b00000111 */
/* if depth % 8 > 0 then one more table is needed
* for those last bits
*/
cnt++;
*need_tbl_nb = cnt;
return 0;
}
next_tbl_ind = tbl[entry_ind].lpm6_tbl8_gindex;
*next_tbl = &(lpm->tbl8[next_tbl_ind *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES]);
*need_tbl_nb = 0;
return 1;
}
/*
* Partially adds a new route to the data structure (tbl24+tbl8s).
* It returns 0 on success, a negative number on failure, or 1 if
* the process needs to be continued by calling the function again.
*/
static inline int
add_step(struct rte_lpm6 *lpm, struct rte_lpm6_tbl_entry *tbl,
uint32_t tbl_ind, struct rte_lpm6_tbl_entry **next_tbl,
uint32_t *next_tbl_ind, uint8_t *ip, uint8_t bytes,
uint8_t first_byte, uint8_t depth, uint32_t next_hop,
uint8_t is_new_rule)
{
uint32_t entry_ind, tbl_range, tbl8_group_start, tbl8_group_end, i;
uint32_t tbl8_gindex;
uint8_t bits_covered;
int ret;
/*
* Calculate index to the table based on the number and position
* of the bytes being inspected in this step.
*/
entry_ind = get_bitshift(ip, first_byte, bytes);
/* Number of bits covered in this step */
bits_covered = (uint8_t)((bytes+first_byte-1)*BYTE_SIZE);
/*
* If depth if smaller than this number (ie this is the last step)
* expand the rule across the relevant positions in the table.
*/
if (depth <= bits_covered) {
tbl_range = 1 << (bits_covered - depth);
for (i = entry_ind; i < (entry_ind + tbl_range); i++) {
if (!tbl[i].valid || (tbl[i].ext_entry == 0 &&
tbl[i].depth <= depth)) {
struct rte_lpm6_tbl_entry new_tbl_entry = {
.next_hop = next_hop,
.depth = depth,
.valid = VALID,
.valid_group = VALID,
.ext_entry = 0,
};
tbl[i] = new_tbl_entry;
} else if (tbl[i].ext_entry == 1) {
/*
* If tbl entry is valid and extended calculate the index
* into next tbl8 and expand the rule across the data structure.
*/
tbl8_gindex = tbl[i].lpm6_tbl8_gindex *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES;
expand_rule(lpm, tbl8_gindex, depth, depth,
next_hop, VALID);
}
}
/* update tbl8 rule reference counter */
if (tbl_ind != TBL24_IND && is_new_rule)
lpm->tbl8_hdrs[tbl_ind].ref_cnt++;
return 0;
}
/*
* If this is not the last step just fill one position
* and calculate the index to the next table.
*/
else {
/* If it's invalid a new tbl8 is needed */
if (!tbl[entry_ind].valid) {
/* get a new table */
ret = tbl8_get(lpm, &tbl8_gindex);
if (ret != 0)
return -ENOSPC;
/* invalidate all new tbl8 entries */
tbl8_group_start = tbl8_gindex *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES;
memset(&lpm->tbl8[tbl8_group_start], 0,
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES *
sizeof(struct rte_lpm6_tbl_entry));
/* init the new table's header:
* save the reference to the owner table
*/
init_tbl8_header(lpm, tbl8_gindex, tbl_ind, entry_ind);
/* reference to a new tbl8 */
struct rte_lpm6_tbl_entry new_tbl_entry = {
.lpm6_tbl8_gindex = tbl8_gindex,
.depth = 0,
.valid = VALID,
.valid_group = VALID,
.ext_entry = 1,
};
tbl[entry_ind] = new_tbl_entry;
/* update the current table's reference counter */
if (tbl_ind != TBL24_IND)
lpm->tbl8_hdrs[tbl_ind].ref_cnt++;
}
/*
* If it's valid but not extended the rule that was stored
* here needs to be moved to the next table.
*/
else if (tbl[entry_ind].ext_entry == 0) {
/* get a new tbl8 index */
ret = tbl8_get(lpm, &tbl8_gindex);
if (ret != 0)
return -ENOSPC;
tbl8_group_start = tbl8_gindex *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES;
tbl8_group_end = tbl8_group_start +
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES;
struct rte_lpm6_tbl_entry tbl_entry = {
.next_hop = tbl[entry_ind].next_hop,
.depth = tbl[entry_ind].depth,
.valid = VALID,
.valid_group = VALID,
.ext_entry = 0
};
/* Populate new tbl8 with tbl value. */
for (i = tbl8_group_start; i < tbl8_group_end; i++)
lpm->tbl8[i] = tbl_entry;
/* init the new table's header:
* save the reference to the owner table
*/
init_tbl8_header(lpm, tbl8_gindex, tbl_ind, entry_ind);
/*
* Update tbl 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_lpm6_tbl_entry new_tbl_entry = {
.lpm6_tbl8_gindex = tbl8_gindex,
.depth = 0,
.valid = VALID,
.valid_group = VALID,
.ext_entry = 1,
};
tbl[entry_ind] = new_tbl_entry;
/* update the current table's reference counter */
if (tbl_ind != TBL24_IND)
lpm->tbl8_hdrs[tbl_ind].ref_cnt++;
}
*next_tbl_ind = tbl[entry_ind].lpm6_tbl8_gindex;
*next_tbl = &(lpm->tbl8[*next_tbl_ind *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES]);
}
return 1;
}
/*
* Simulate adding a route to LPM
*
* Returns:
* 0 on success
* -ENOSPC not enough tbl8 left
*/
static int
simulate_add(struct rte_lpm6 *lpm, const uint8_t *masked_ip, uint8_t depth)
{
struct rte_lpm6_tbl_entry *tbl;
struct rte_lpm6_tbl_entry *tbl_next = NULL;
int ret, i;
/* number of new tables needed for a step */
uint32_t need_tbl_nb;
/* total number of new tables needed */
uint32_t total_need_tbl_nb;
/* Inspect the first three bytes through tbl24 on the first step. */
ret = simulate_add_step(lpm, lpm->tbl24, &tbl_next, masked_ip,
ADD_FIRST_BYTE, 1, depth, &need_tbl_nb);
total_need_tbl_nb = need_tbl_nb;
/*
* Inspect one by one the rest of the bytes until
* the process is completed.
*/
for (i = ADD_FIRST_BYTE; i < RTE_LPM6_IPV6_ADDR_SIZE && ret == 1; i++) {
tbl = tbl_next;
ret = simulate_add_step(lpm, tbl, &tbl_next, masked_ip, 1,
(uint8_t)(i + 1), depth, &need_tbl_nb);
total_need_tbl_nb += need_tbl_nb;
}
if (tbl8_available(lpm) < total_need_tbl_nb)
/* not enough tbl8 to add a rule */
return -ENOSPC;
return 0;
}
/*
* Add a route
*/
int
rte_lpm6_add(struct rte_lpm6 *lpm, const uint8_t *ip, uint8_t depth,
uint32_t next_hop, int is_new_rule)
{
struct rte_lpm6_tbl_entry *tbl;
struct rte_lpm6_tbl_entry *tbl_next = NULL;
/* init to avoid compiler warning */
uint32_t tbl_next_num = 123456;
int status;
uint8_t masked_ip[RTE_LPM6_IPV6_ADDR_SIZE];
int i;
/* Check user arguments. */
if ((lpm == NULL) || (depth < 1) || (depth > RTE_LPM6_MAX_DEPTH))
return -EINVAL;
/* Copy the IP and mask it to avoid modifying user's input data. */
ip6_copy_addr(masked_ip, ip);
ip6_mask_addr(masked_ip, depth);
/* Simulate adding a new route */
int ret = simulate_add(lpm, masked_ip, depth);
if (ret < 0)
return ret;
#if 0
/* Add the rule to the rule table. */
int is_new_rule = rule_add(lpm, masked_ip, depth, next_hop);
/* If there is no space available for new rule return error. */
if (is_new_rule < 0)
return is_new_rule;
#endif
/* Inspect the first three bytes through tbl24 on the first step. */
tbl = lpm->tbl24;
status = add_step(lpm, tbl, TBL24_IND, &tbl_next, &tbl_next_num,
masked_ip, ADD_FIRST_BYTE, 1, depth, next_hop,
is_new_rule);
assert(status >= 0);
/*
* Inspect one by one the rest of the bytes until
* the process is completed.
*/
for (i = ADD_FIRST_BYTE; i < RTE_LPM6_IPV6_ADDR_SIZE && status == 1; i++) {
tbl = tbl_next;
status = add_step(lpm, tbl, tbl_next_num, &tbl_next,
&tbl_next_num, masked_ip, 1, (uint8_t)(i + 1),
depth, next_hop, is_new_rule);
assert(status >= 0);
}
return status;
}
/*
* Takes a pointer to a table entry and inspect one level.
* The function returns 0 on lookup success, ENOENT if no match was found
* or 1 if the process needs to be continued by calling the function again.
*/
static inline int
lookup_step(const struct rte_lpm6 *lpm, const struct rte_lpm6_tbl_entry *tbl,
const struct rte_lpm6_tbl_entry **tbl_next, const uint8_t *ip,
uint8_t first_byte, uint32_t *next_hop)
{
uint32_t tbl8_index, tbl_entry;
/* Take the integer value from the pointer. */
tbl_entry = *(const uint32_t *)tbl;
/* If it is valid and extended we calculate the new pointer to return. */
if ((tbl_entry & RTE_LPM6_VALID_EXT_ENTRY_BITMASK) ==
RTE_LPM6_VALID_EXT_ENTRY_BITMASK) {
tbl8_index = ip[first_byte-1] +
((tbl_entry & RTE_LPM6_TBL8_BITMASK) *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES);
*tbl_next = &lpm->tbl8[tbl8_index];
return 1;
} else {
/* If not extended then we can have a match. */
*next_hop = ((uint32_t)tbl_entry & RTE_LPM6_TBL8_BITMASK);
return (tbl_entry & RTE_LPM6_LOOKUP_SUCCESS) ? 0 : -ENOENT;
}
}
/*
* Looks up an IP
*/
int
rte_lpm6_lookup(const struct rte_lpm6 *lpm, const uint8_t *ip,
uint32_t *next_hop)
{
const struct rte_lpm6_tbl_entry *tbl;
const struct rte_lpm6_tbl_entry *tbl_next = NULL;
int status;
uint8_t first_byte;
uint32_t tbl24_index;
/* DEBUG: Check user input arguments. */
if ((lpm == NULL) || (ip == NULL) || (next_hop == NULL))
return -EINVAL;
first_byte = LOOKUP_FIRST_BYTE;
tbl24_index = (ip[0] << BYTES2_SIZE) | (ip[1] << BYTE_SIZE) | ip[2];
/* Calculate pointer to the first entry to be inspected */
tbl = &lpm->tbl24[tbl24_index];
do {
/* Continue inspecting following levels until success or failure */
status = lookup_step(lpm, tbl, &tbl_next, ip, first_byte++, next_hop);
tbl = tbl_next;
} while (status == 1);
return status;
}
/*
* Looks up a group of IP addresses
*/
int
rte_lpm6_lookup_bulk_func(const struct rte_lpm6 *lpm,
uint8_t ips[][RTE_LPM6_IPV6_ADDR_SIZE],
int32_t *next_hops, unsigned int n)
{
unsigned int i;
const struct rte_lpm6_tbl_entry *tbl;
const struct rte_lpm6_tbl_entry *tbl_next = NULL;
uint32_t tbl24_index, next_hop;
uint8_t first_byte;
int status;
/* DEBUG: Check user input arguments. */
if ((lpm == NULL) || (ips == NULL) || (next_hops == NULL))
return -EINVAL;
for (i = 0; i < n; i++) {
first_byte = LOOKUP_FIRST_BYTE;
tbl24_index = (ips[i][0] << BYTES2_SIZE) |
(ips[i][1] << BYTE_SIZE) | ips[i][2];
/* Calculate pointer to the first entry to be inspected */
tbl = &lpm->tbl24[tbl24_index];
do {
/* Continue inspecting following levels
* until success or failure
*/
status = lookup_step(lpm, tbl, &tbl_next, ips[i],
first_byte++, &next_hop);
tbl = tbl_next;
} while (status == 1);
if (status < 0)
next_hops[i] = -1;
else
next_hops[i] = (int32_t)next_hop;
}
return 0;
}
struct rte_lpm6_rule *
fill_rule6(char *buffer, const uint8_t *ip, uint8_t depth, uint32_t next_hop)
{
struct rte_lpm6_rule *rule = (struct rte_lpm6_rule *)buffer;
ip6_copy_addr((uint8_t *)&rule->ip, ip);
rule->depth = depth;
rule->next_hop = next_hop;
return (rule);
}
#if 0
/*
* Look for a rule in the high-level rules table
*/
int
rte_lpm6_is_rule_present(struct rte_lpm6 *lpm, const uint8_t *ip, uint8_t depth,
uint32_t *next_hop)
{
uint8_t masked_ip[RTE_LPM6_IPV6_ADDR_SIZE];
/* Check user arguments. */
if ((lpm == NULL) || next_hop == NULL || ip == NULL ||
(depth < 1) || (depth > RTE_LPM6_MAX_DEPTH))
return -EINVAL;
/* Copy the IP and mask it to avoid modifying user's input data. */
ip6_copy_addr(masked_ip, ip);
ip6_mask_addr(masked_ip, depth);
return rule_find(lpm, masked_ip, depth, next_hop);
}
/*
* Delete a rule from the rule table.
* NOTE: Valid range for depth parameter is 1 .. 128 inclusive.
* return
* 0 on success
* <0 on failure
*/
static inline int
rule_delete(struct rte_lpm6 *lpm, uint8_t *ip, uint8_t depth)
{
int ret;
struct rte_lpm6_rule_key rule_key;
/* init rule key */
rule_key_init(&rule_key, ip, depth);
/* delete the rule */
ret = rte_hash_del_key(lpm->rules_tbl, (void *) &rule_key);
if (ret >= 0)
lpm->used_rules--;
return ret;
}
/*
* Deletes a group of rules
*
* Note that the function rebuilds the lpm table,
* rather than doing incremental updates like
* the regular delete function
*/
int
rte_lpm6_delete_bulk_func(struct rte_lpm6 *lpm,
uint8_t ips[][RTE_LPM6_IPV6_ADDR_SIZE], uint8_t *depths,
unsigned n)
{
uint8_t masked_ip[RTE_LPM6_IPV6_ADDR_SIZE];
unsigned i;
/* Check input arguments. */
if ((lpm == NULL) || (ips == NULL) || (depths == NULL))
return -EINVAL;
for (i = 0; i < n; i++) {
ip6_copy_addr(masked_ip, ips[i]);
ip6_mask_addr(masked_ip, depths[i]);
rule_delete(lpm, masked_ip, depths[i]);
}
/*
* Set all the table entries to 0 (ie delete every rule
* from the data structure.
*/
memset(lpm->tbl24, 0, sizeof(lpm->tbl24));
memset(lpm->tbl8, 0, sizeof(lpm->tbl8[0])
* RTE_LPM6_TBL8_GROUP_NUM_ENTRIES * lpm->number_tbl8s);
tbl8_pool_init(lpm);
/*
* Add every rule again (except for the ones that were removed from
* the rules table).
*/
rebuild_lpm(lpm);
return 0;
}
/*
* Delete all rules from the LPM table.
*/
void
rte_lpm6_delete_all(struct rte_lpm6 *lpm)
{
/* Zero used rules counter. */
lpm->used_rules = 0;
/* Zero tbl24. */
memset(lpm->tbl24, 0, sizeof(lpm->tbl24));
/* Zero tbl8. */
memset(lpm->tbl8, 0, sizeof(lpm->tbl8[0]) *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES * lpm->number_tbl8s);
/* init pool of free tbl8 indexes */
tbl8_pool_init(lpm);
/* Delete all rules form the rules table. */
rte_hash_reset(lpm->rules_tbl);
}
#endif
/*
* Convert a depth to a one byte long mask
* Example: 4 will be converted to 0xF0
*/
static uint8_t __attribute__((pure))
depth_to_mask_1b(uint8_t 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 (signed char)0x80 >> (depth - 1);
}
#if 0
/*
* Find a less specific rule
*/
static int
rule_find_less_specific(struct rte_lpm6 *lpm, uint8_t *ip, uint8_t depth,
struct rte_lpm6_rule *rule)
{
int ret;
uint32_t next_hop;
uint8_t mask;
struct rte_lpm6_rule_key rule_key;
if (depth == 1)
return 0;
rule_key_init(&rule_key, ip, depth);
while (depth > 1) {
depth--;
/* each iteration zero one more bit of the key */
mask = depth & 7; /* depth % BYTE_SIZE */
if (mask > 0)
mask = depth_to_mask_1b(mask);
rule_key.depth = depth;
rule_key.ip[depth >> 3] &= mask;
ret = rule_find_with_key(lpm, &rule_key, &next_hop);
if (ret) {
rule->depth = depth;
ip6_copy_addr(rule->ip, rule_key.ip);
rule->next_hop = next_hop;
return 1;
}
}
return 0;
}
#endif
/*
* Find range of tbl8 cells occupied by a rule
*/
static void
rule_find_range(struct rte_lpm6 *lpm, const uint8_t *ip, uint8_t depth,
struct rte_lpm6_tbl_entry **from,
struct rte_lpm6_tbl_entry **to,
uint32_t *out_tbl_ind)
{
uint32_t ind;
uint32_t first_3bytes = (uint32_t)ip[0] << 16 | ip[1] << 8 | ip[2];
if (depth <= 24) {
/* rule is within the top level */
ind = first_3bytes;
*from = &lpm->tbl24[ind];
ind += (1 << (24 - depth)) - 1;
*to = &lpm->tbl24[ind];
*out_tbl_ind = TBL24_IND;
} else {
/* top level entry */
struct rte_lpm6_tbl_entry *tbl = &lpm->tbl24[first_3bytes];
assert(tbl->ext_entry == 1);
/* first tbl8 */
uint32_t tbl_ind = tbl->lpm6_tbl8_gindex;
tbl = &lpm->tbl8[tbl_ind *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES];
/* current ip byte, the top level is already behind */
uint8_t byte = 3;
/* minus top level */
depth -= 24;
/* iterate through levels (tbl8s)
* until we reach the last one
*/
while (depth > 8) {
tbl += ip[byte];
assert(tbl->ext_entry == 1);
/* go to the next level/tbl8 */
tbl_ind = tbl->lpm6_tbl8_gindex;
tbl = &lpm->tbl8[tbl_ind *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES];
byte += 1;
depth -= 8;
}
/* last level/tbl8 */
ind = ip[byte] & depth_to_mask_1b(depth);
*from = &tbl[ind];
ind += (1 << (8 - depth)) - 1;
*to = &tbl[ind];
*out_tbl_ind = tbl_ind;
}
}
/*
* Remove a table from the LPM tree
*/
static void
remove_tbl(struct rte_lpm6 *lpm, struct rte_lpm_tbl8_hdr *tbl_hdr,
uint32_t tbl_ind, struct rte_lpm6_rule *lsp_rule)
{
struct rte_lpm6_tbl_entry *owner_entry;
if (tbl_hdr->owner_tbl_ind == TBL24_IND)
owner_entry = &lpm->tbl24[tbl_hdr->owner_entry_ind];
else {
uint32_t owner_tbl_ind = tbl_hdr->owner_tbl_ind;
owner_entry = &lpm->tbl8[
owner_tbl_ind * RTE_LPM6_TBL8_GROUP_NUM_ENTRIES +
tbl_hdr->owner_entry_ind];
struct rte_lpm_tbl8_hdr *owner_tbl_hdr =
&lpm->tbl8_hdrs[owner_tbl_ind];
if (--owner_tbl_hdr->ref_cnt == 0)
remove_tbl(lpm, owner_tbl_hdr, owner_tbl_ind, lsp_rule);
}
assert(owner_entry->ext_entry == 1);
/* unlink the table */
if (lsp_rule != NULL) {
struct rte_lpm6_tbl_entry new_tbl_entry = {
.next_hop = lsp_rule->next_hop,
.depth = lsp_rule->depth,
.valid = VALID,
.valid_group = VALID,
.ext_entry = 0
};
*owner_entry = new_tbl_entry;
} else {
struct rte_lpm6_tbl_entry new_tbl_entry = {
.next_hop = 0,
.depth = 0,
.valid = INVALID,
.valid_group = INVALID,
.ext_entry = 0
};
*owner_entry = new_tbl_entry;
}
/* return the table to the pool */
tbl8_put(lpm, tbl_ind);
}
/*
* Deletes a rule
*/
int
rte_lpm6_delete(struct rte_lpm6 *lpm, const uint8_t *ip, uint8_t depth,
struct rte_lpm6_rule *lsp_rule)
{
uint8_t masked_ip[RTE_LPM6_IPV6_ADDR_SIZE];
//struct rte_lpm6_rule lsp_rule_obj;
//struct rte_lpm6_rule *lsp_rule;
//int ret;
uint32_t tbl_ind;
struct rte_lpm6_tbl_entry *from, *to;
/* Check input arguments. */
if ((lpm == NULL) || (depth < 1) || (depth > RTE_LPM6_MAX_DEPTH))
return -EINVAL;
/* Copy the IP and mask it to avoid modifying user's input data. */
ip6_copy_addr(masked_ip, ip);
ip6_mask_addr(masked_ip, depth);
#if 0
/* Delete the rule from the rule table. */
ret = rule_delete(lpm, masked_ip, depth);
if (ret < 0)
return -ENOENT;
#endif
/* find rule cells */
rule_find_range(lpm, masked_ip, depth, &from, &to, &tbl_ind);
#if 0
/* find a less specific rule (a rule with smaller depth)
* note: masked_ip will be modified, don't use it anymore
*/
ret = rule_find_less_specific(lpm, masked_ip, depth,
&lsp_rule_obj);
lsp_rule = ret ? &lsp_rule_obj : NULL;
#endif
/* decrement the table rule counter,
* note that tbl24 doesn't have a header
*/
if (tbl_ind != TBL24_IND) {
struct rte_lpm_tbl8_hdr *tbl_hdr = &lpm->tbl8_hdrs[tbl_ind];
if (--tbl_hdr->ref_cnt == 0) {
/* remove the table */
remove_tbl(lpm, tbl_hdr, tbl_ind, lsp_rule);
return 0;
}
}
/* iterate rule cells */
for (; from <= to; from++)
if (from->ext_entry == 1) {
/* reference to a more specific space
* of the prefix/rule. Entries in a more
* specific space that are not used by
* a more specific prefix must be occupied
* by the prefix
*/
if (lsp_rule != NULL)
expand_rule(lpm,
from->lpm6_tbl8_gindex *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES,
depth, lsp_rule->depth,
lsp_rule->next_hop, VALID);
else
/* since the prefix has no less specific prefix,
* its more specific space must be invalidated
*/
expand_rule(lpm,
from->lpm6_tbl8_gindex *
RTE_LPM6_TBL8_GROUP_NUM_ENTRIES,
depth, 0, 0, INVALID);
} else if (from->depth == depth) {
/* entry is not a reference and belongs to the prefix */
if (lsp_rule != NULL) {
struct rte_lpm6_tbl_entry new_tbl_entry = {
.next_hop = lsp_rule->next_hop,
.depth = lsp_rule->depth,
.valid = VALID,
.valid_group = VALID,
.ext_entry = 0
};
*from = new_tbl_entry;
} else {
struct rte_lpm6_tbl_entry new_tbl_entry = {
.next_hop = 0,
.depth = 0,
.valid = INVALID,
.valid_group = INVALID,
.ext_entry = 0
};
*from = new_tbl_entry;
}
}
return 0;
}