blob: 68d28b9501212eda3889dc8e8c0609d6ee114dce [file] [log] [blame]
Thomas Wu68250352014-04-02 18:59:40 -07001/*
2 **************************************************************************
3 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
4 * Permission to use, copy, modify, and/or distribute this software for
5 * any purpose with or without fee is hereby granted, provided that the
6 * above copyright notice and this permission notice appear in all copies.
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
10 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
12 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
13 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
14 **************************************************************************
15 */
16
17/*
Murat Sezgin5c8c7362014-09-02 17:58:21 -070018 * nss_ipv4.c
Thomas Wu68250352014-04-02 18:59:40 -070019 * NSS IPv4 APIs
20 */
Vijay Dewangan9db18752014-09-15 16:25:01 -070021#include <linux/sysctl.h>
Thomas Wu68250352014-04-02 18:59:40 -070022#include <linux/ppp_channel.h>
23#include "nss_tx_rx_common.h"
Thomas Wu68250352014-04-02 18:59:40 -070024
25extern void nss_rx_metadata_ipv4_rule_establish(struct nss_ctx_instance *nss_ctx, struct nss_ipv4_rule_establish *nire);
Sakthi Vignesh Radhakrishnan515f8c22014-06-21 15:04:19 -070026extern void nss_rx_metadata_ipv4_create_response(struct nss_ctx_instance *nss_ctx, struct nss_ipv4_msg *nim);
Thomas Wu68250352014-04-02 18:59:40 -070027extern void nss_rx_ipv4_sync(struct nss_ctx_instance *nss_ctx, struct nss_ipv4_conn_sync *nirs);
28
Vijay Dewangan9db18752014-09-15 16:25:01 -070029int nss_ipv4_conn_cfg __read_mostly = 4096;
30
Thomas Wu68250352014-04-02 18:59:40 -070031/*
Sol Kavy57d24b42014-04-05 13:45:36 -070032 * nss_ipv4_driver_conn_sync_update()
Thomas Wu68250352014-04-02 18:59:40 -070033 * Update driver specific information from the messsage.
34 */
Murat Sezgin0c0561d2014-04-09 18:55:58 -070035static void nss_ipv4_driver_conn_sync_update(struct nss_ctx_instance *nss_ctx, struct nss_ipv4_conn_sync *nirs)
Thomas Wu68250352014-04-02 18:59:40 -070036{
Sol Kavy57d24b42014-04-05 13:45:36 -070037 struct nss_top_instance *nss_top = nss_ctx->nss_top;
38 struct net_device *pppoe_dev = NULL;
39
Thomas Wu68250352014-04-02 18:59:40 -070040 /*
41 * Update statistics maintained by NSS driver
42 */
43 spin_lock_bh(&nss_top->stats_lock);
Thomas Wu68250352014-04-02 18:59:40 -070044 nss_top->stats_ipv4[NSS_STATS_IPV4_ACCELERATED_RX_PKTS] += nirs->flow_rx_packet_count + nirs->return_rx_packet_count;
45 nss_top->stats_ipv4[NSS_STATS_IPV4_ACCELERATED_RX_BYTES] += nirs->flow_rx_byte_count + nirs->return_rx_byte_count;
46 nss_top->stats_ipv4[NSS_STATS_IPV4_ACCELERATED_TX_PKTS] += nirs->flow_tx_packet_count + nirs->return_tx_packet_count;
47 nss_top->stats_ipv4[NSS_STATS_IPV4_ACCELERATED_TX_BYTES] += nirs->flow_tx_byte_count + nirs->return_tx_byte_count;
Thomas Wu68250352014-04-02 18:59:40 -070048 spin_unlock_bh(&nss_top->stats_lock);
Sol Kavy57d24b42014-04-05 13:45:36 -070049
50 /*
51 * Update the PPPoE interface stats, if there is any PPPoE session on the interfaces.
52 */
53 if (nirs->flow_pppoe_session_id) {
54 pppoe_dev = ppp_session_to_netdev(nirs->flow_pppoe_session_id, (uint8_t *)nirs->flow_pppoe_remote_mac);
55 if (pppoe_dev) {
56 ppp_update_stats(pppoe_dev, nirs->flow_rx_packet_count, nirs->flow_rx_byte_count,
57 nirs->flow_tx_packet_count, nirs->flow_tx_byte_count);
58 dev_put(pppoe_dev);
59 }
60 }
61
62 if (nirs->return_pppoe_session_id) {
63 pppoe_dev = ppp_session_to_netdev(nirs->return_pppoe_session_id, (uint8_t *)nirs->return_pppoe_remote_mac);
64 if (pppoe_dev) {
65 ppp_update_stats(pppoe_dev, nirs->return_rx_packet_count, nirs->return_rx_byte_count,
66 nirs->return_tx_packet_count, nirs->return_tx_byte_count);
67 dev_put(pppoe_dev);
68 }
69 }
Thomas Wu68250352014-04-02 18:59:40 -070070}
Thomas Wu68250352014-04-02 18:59:40 -070071
72/*
Murat Sezgin0c0561d2014-04-09 18:55:58 -070073 * nss_ipv4_driver_node_sync_update)
74 * Update driver specific information from the messsage.
75 */
76static void nss_ipv4_driver_node_sync_update(struct nss_ctx_instance *nss_ctx, struct nss_ipv4_node_sync *nins)
77{
78 struct nss_top_instance *nss_top = nss_ctx->nss_top;
79 uint32_t i;
80
81 /*
82 * Update statistics maintained by NSS driver
83 */
84 spin_lock_bh(&nss_top->stats_lock);
85 nss_top->stats_node[NSS_IPV4_RX_INTERFACE][NSS_STATS_NODE_RX_PKTS] += nins->node_stats.rx_packets;
86 nss_top->stats_node[NSS_IPV4_RX_INTERFACE][NSS_STATS_NODE_RX_BYTES] += nins->node_stats.rx_bytes;
87 nss_top->stats_node[NSS_IPV4_RX_INTERFACE][NSS_STATS_NODE_RX_DROPPED] += nins->node_stats.rx_dropped;
88 nss_top->stats_node[NSS_IPV4_RX_INTERFACE][NSS_STATS_NODE_TX_PKTS] += nins->node_stats.tx_packets;
89 nss_top->stats_node[NSS_IPV4_RX_INTERFACE][NSS_STATS_NODE_TX_BYTES] += nins->node_stats.tx_bytes;
90
Murat Sezgin0c0561d2014-04-09 18:55:58 -070091 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_CREATE_REQUESTS] += nins->ipv4_connection_create_requests;
92 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_CREATE_COLLISIONS] += nins->ipv4_connection_create_collisions;
93 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_CREATE_INVALID_INTERFACE] += nins->ipv4_connection_create_invalid_interface;
94 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_DESTROY_REQUESTS] += nins->ipv4_connection_destroy_requests;
95 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_DESTROY_MISSES] += nins->ipv4_connection_destroy_misses;
96 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_HASH_HITS] += nins->ipv4_connection_hash_hits;
97 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_HASH_REORDERS] += nins->ipv4_connection_hash_reorders;
98 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_FLUSHES] += nins->ipv4_connection_flushes;
99 nss_top->stats_ipv4[NSS_STATS_IPV4_CONNECTION_EVICTIONS] += nins->ipv4_connection_evictions;
100
101 for (i = 0; i < NSS_EXCEPTION_EVENT_IPV4_MAX; i++) {
102 nss_top->stats_if_exception_ipv4[i] += nins->exception_events[i];
103 }
104 spin_unlock_bh(&nss_top->stats_lock);
105}
106
107/*
Sol Kavy2783c072014-04-05 12:53:13 -0700108 * nss_ipv4_rx_msg_handler()
Thomas Wu68250352014-04-02 18:59:40 -0700109 * Handle NSS -> HLOS messages for IPv4 bridge/route
110 */
Sol Kavy2783c072014-04-05 12:53:13 -0700111static void nss_ipv4_rx_msg_handler(struct nss_ctx_instance *nss_ctx, struct nss_cmn_msg *ncm, __attribute__((unused))void *app_data)
Thomas Wu68250352014-04-02 18:59:40 -0700112{
113 struct nss_ipv4_msg *nim = (struct nss_ipv4_msg *)ncm;
Sol Kavy57d24b42014-04-05 13:45:36 -0700114 nss_ipv4_msg_callback_t cb;
Thomas Wu68250352014-04-02 18:59:40 -0700115
116 BUG_ON(ncm->interface != NSS_IPV4_RX_INTERFACE);
117
118 /*
119 * Sanity check the message type
120 */
Murat Sezgin5c8c7362014-09-02 17:58:21 -0700121 if (ncm->type >= NSS_IPV4_MAX_MSG_TYPES) {
Thomas Wu68250352014-04-02 18:59:40 -0700122 nss_warning("%p: message type out of range: %d", nss_ctx, ncm->type);
123 return;
124 }
125
126 if (ncm->len > sizeof(struct nss_ipv4_msg)) {
127 nss_warning("%p: tx request for another interface: %d", nss_ctx, ncm->interface);
128 return;
129 }
130
Thomas Wu68250352014-04-02 18:59:40 -0700131 /*
Thomas Wu68250352014-04-02 18:59:40 -0700132 * Log failures
133 */
134 nss_core_log_msg_failures(nss_ctx, ncm);
135
136 /*
137 * Handle deprecated messages. Eventually these messages should be removed.
138 */
139 switch (nim->cm.type) {
140 case NSS_IPV4_RX_ESTABLISH_RULE_MSG:
141 return nss_rx_metadata_ipv4_rule_establish(nss_ctx, &nim->msg.rule_establish);
142 break;
143
Murat Sezgin0c0561d2014-04-09 18:55:58 -0700144 case NSS_IPV4_RX_NODE_STATS_SYNC_MSG:
145 /*
146 * Update driver statistics on node sync.
147 */
148 nss_ipv4_driver_node_sync_update(nss_ctx, &nim->msg.node_stats);
149 break;
150
Thomas Wu68250352014-04-02 18:59:40 -0700151 case NSS_IPV4_RX_CONN_STATS_SYNC_MSG:
Sol Kavy57d24b42014-04-05 13:45:36 -0700152 /*
153 * Update driver statistics on connection sync.
154 */
155 nss_ipv4_driver_conn_sync_update(nss_ctx, &nim->msg.conn_stats);
Sol Kavy4013e282014-04-06 15:57:00 -0700156 nss_rx_ipv4_sync(nss_ctx, &nim->msg.conn_stats);
Thomas Wu68250352014-04-02 18:59:40 -0700157 break;
Sakthi Vignesh Radhakrishnan515f8c22014-06-21 15:04:19 -0700158
159 case NSS_IPV4_TX_CREATE_RULE_MSG:
160 nss_rx_metadata_ipv4_create_response(nss_ctx, nim);
161 break;
Thomas Wu68250352014-04-02 18:59:40 -0700162 }
163
164 /*
Sol Kavy57d24b42014-04-05 13:45:36 -0700165 * Update the callback and app_data for NOTIFY messages, IPv4 sends all notify messages
166 * to the same callback/app_data.
Thomas Wu68250352014-04-02 18:59:40 -0700167 */
Sol Kavy57d24b42014-04-05 13:45:36 -0700168 if (nim->cm.response == NSS_CMM_RESPONSE_NOTIFY) {
169 ncm->cb = (uint32_t)nss_ctx->nss_top->ipv4_callback;
170 ncm->app_data = (uint32_t)nss_ctx->nss_top->ipv4_ctx;
171 }
Sol Kavy2783c072014-04-05 12:53:13 -0700172
Thomas Wu68250352014-04-02 18:59:40 -0700173 /*
174 * Do we have a callback?
175 */
176 if (!ncm->cb) {
177 return;
178 }
179
180 /*
181 * Callback
182 */
Sol Kavy57d24b42014-04-05 13:45:36 -0700183 cb = (nss_ipv4_msg_callback_t)ncm->cb;
Thomas Wu68250352014-04-02 18:59:40 -0700184 cb((void *)ncm->app_data, nim);
Thomas Wu68250352014-04-02 18:59:40 -0700185}
186
187/*
188 * nss_ipv4_tx()
189 * Transmit an ipv4 message to the FW.
190 */
191nss_tx_status_t nss_ipv4_tx(struct nss_ctx_instance *nss_ctx, struct nss_ipv4_msg *nim)
192{
193 struct nss_ipv4_msg *nim2;
194 struct nss_cmn_msg *ncm = &nim->cm;
195 struct sk_buff *nbuf;
196 int32_t status;
197
198 NSS_VERIFY_CTX_MAGIC(nss_ctx);
199 if (unlikely(nss_ctx->state != NSS_CORE_STATE_INITIALIZED)) {
200 nss_warning("%p: ipv4 msg dropped as core not ready", nss_ctx);
201 return NSS_TX_FAILURE_NOT_READY;
202 }
203
204 /*
205 * Sanity check the message
206 */
207 if (ncm->interface != NSS_IPV4_RX_INTERFACE) {
208 nss_warning("%p: tx request for another interface: %d", nss_ctx, ncm->interface);
209 return NSS_TX_FAILURE;
210 }
211
Murat Sezgin5c8c7362014-09-02 17:58:21 -0700212 if (ncm->type >= NSS_IPV4_MAX_MSG_TYPES) {
Thomas Wu68250352014-04-02 18:59:40 -0700213 nss_warning("%p: message type out of range: %d", nss_ctx, ncm->type);
214 return NSS_TX_FAILURE;
215 }
216
217 if (ncm->len > sizeof(struct nss_ipv4_msg)) {
218 nss_warning("%p: tx request for another interface: %d", nss_ctx, ncm->interface);
219 return NSS_TX_FAILURE;
220 }
221
Pamidipati, Vijayb6e38842014-09-16 10:26:05 +0530222 nbuf = dev_alloc_skb(NSS_NBUF_PAYLOAD_SIZE);
Thomas Wu68250352014-04-02 18:59:40 -0700223 if (unlikely(!nbuf)) {
224 spin_lock_bh(&nss_ctx->nss_top->stats_lock);
225 nss_ctx->nss_top->stats_drv[NSS_STATS_DRV_NBUF_ALLOC_FAILS]++;
226 spin_unlock_bh(&nss_ctx->nss_top->stats_lock);
227 nss_warning("%p: msg dropped as command allocation failed", nss_ctx);
228 return NSS_TX_FAILURE;
229 }
230
231 /*
232 * Copy the message to our skb.
233 */
234 nim2 = (struct nss_ipv4_msg *)skb_put(nbuf, sizeof(struct nss_ipv4_msg));
235 memcpy(nim2, nim, sizeof(struct nss_ipv4_msg));
236
237 status = nss_core_send_buffer(nss_ctx, 0, nbuf, NSS_IF_CMD_QUEUE, H2N_BUFFER_CTRL, 0);
238 if (status != NSS_CORE_STATUS_SUCCESS) {
Pamidipati, Vijayb6e38842014-09-16 10:26:05 +0530239 dev_kfree_skb_any(nbuf);
Sol Kavycd1bd5c2014-04-04 11:09:44 -0700240 nss_warning("%p: unable to enqueue IPv4 msg\n", nss_ctx);
Thomas Wu68250352014-04-02 18:59:40 -0700241 return NSS_TX_FAILURE;
242 }
243
244 nss_hal_send_interrupt(nss_ctx->nmap, nss_ctx->h2n_desc_rings[NSS_IF_CMD_QUEUE].desc_ring.int_bit,
245 NSS_REGS_H2N_INTR_STATUS_DATA_COMMAND_QUEUE);
246
247 NSS_PKT_STATS_INCREMENT(nss_ctx, &nss_ctx->nss_top->stats_drv[NSS_STATS_DRV_TX_CMD_REQ]);
248 return NSS_TX_SUCCESS;
249}
250
251/*
252 **********************************
253 Register/Unregister/Miscellaneous APIs
254 **********************************
255 */
256
257/*
258 * nss_ipv4_notify_register()
259 * Register to received IPv4 events.
260 *
261 * NOTE: Do we want to pass an nss_ctx here so that we can register for ipv4 on any core?
262 */
263struct nss_ctx_instance *nss_ipv4_notify_register(nss_ipv4_msg_callback_t cb, void *app_data)
264{
265 /*
266 * TODO: We need to have a new array in support of the new API
267 * TODO: If we use a per-context array, we would move the array into nss_ctx based.
268 */
269 nss_top_main.ipv4_callback = cb;
Abhishek Rastogie11f47b2014-04-04 18:43:32 +0530270 nss_top_main.ipv4_ctx = app_data;
Thomas Wu68250352014-04-02 18:59:40 -0700271 return &nss_top_main.nss[nss_top_main.ipv4_handler_id];
272}
273
274/*
275 * nss_ipv4_notify_unregister()
276 * Unregister to received IPv4 events.
277 *
278 * NOTE: Do we want to pass an nss_ctx here so that we can register for ipv4 on any core?
279 */
280void nss_ipv4_notify_unregister(void)
281{
282 nss_top_main.ipv4_callback = NULL;
283}
284
285/*
286 * nss_ipv4_get_mgr()
287 *
288 * TODO: This only suppports a single ipv4, do we ever want to support more?
289 */
290struct nss_ctx_instance *nss_ipv4_get_mgr(void)
291{
292 return (void *)&nss_top_main.nss[nss_top_main.ipv4_handler_id];
293}
294
295/*
296 * nss_ipv4_register_handler()
297 * Register our handler to receive messages for this interface
298 */
Sol Kavy2783c072014-04-05 12:53:13 -0700299void nss_ipv4_register_handler(void)
Thomas Wu68250352014-04-02 18:59:40 -0700300{
Sol Kavy2783c072014-04-05 12:53:13 -0700301 if (nss_core_register_handler(NSS_IPV4_RX_INTERFACE, nss_ipv4_rx_msg_handler, NULL) != NSS_CORE_STATUS_SUCCESS) {
Thomas Wu68250352014-04-02 18:59:40 -0700302 nss_warning("IPv4 handler failed to register");
303 }
304}
305
Vijay Dewangan9db18752014-09-15 16:25:01 -0700306/*
307 * nss_ipv4_conn_cfg_callback()
308 * call back function for the ipv6 connection configuration handler
309 */
310static void nss_ipv4_conn_cfg_callback(void *app_data, struct nss_if_msg *nim)
311{
312
313 if (nim->cm.response != NSS_CMN_RESPONSE_ACK) {
314 nss_warning("IPv4 connection configuration failed with error: %d\n", nim->cm.error);
315 return;
316 }
317
318 nss_info("IPv4 connection configuration success: %d\n", nim->cm.error);
319}
320
321/*
322 * nss_ipv4_conn_cfg_handler()
323 * Sets the number of connections for IPv4
324 */
325static int nss_ipv4_conn_cfg_handler(ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
326{
327 struct nss_top_instance *nss_top = &nss_top_main;
328 struct nss_ctx_instance *nss_ctx = &nss_top->nss[0];
329 struct nss_ipv4_msg nim;
330 struct nss_ipv4_rule_conn_cfg_msg *nirccm;
331 nss_tx_status_t nss_tx_status;
332 int ret = 1;
333 uint32_t sum_of_conn = nss_ipv4_conn_cfg + nss_ipv6_conn_cfg;
334
335 /*
336 * The input should be power of 2.
337 * Input for ipv4 and ipv6 sum togther should not exceed 8k
338 * Min. value should be at leat 256 connections. This is the
339 * minimum connections we will support for each of them.
340 */
341 if ((nss_ipv4_conn_cfg & (nss_ipv4_conn_cfg - 1)) ||
342 (sum_of_conn > MAX_TOTAL_NUM_CONN_IPV4_IPV6) ||
343 (nss_ipv4_conn_cfg < MIN_NUM_CONN)) {
344 nss_warning("%p: input supported connections (%d) does not adhere\
345 specifications\n1) not power of 2,\n2) is less than \
346 min val: %d, OR\n IPv4/6 total exceeds %d\n",
347 nss_ctx,
348 nss_ipv4_conn_cfg,
349 MIN_NUM_CONN,
350 MAX_TOTAL_NUM_CONN_IPV4_IPV6);
351 return ret;
352 }
353
354 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
355
356 if (ret) {
357 return ret;
358 }
359
360 if ((!write)) {
361 nss_warning("%p: IPv4 supported connections write failed: %d\n", nss_ctx, nss_ipv4_conn_cfg);
362 return ret;
363 }
364
365
366 nss_info("%p: IPv4 supported connections: %d\n", nss_ctx, nss_ipv4_conn_cfg);
367
368 nss_cmn_msg_init(&nim.cm, NSS_IPV4_RX_INTERFACE, NSS_IPV4_TX_CONN_CFG_RULE_MSG,
369 sizeof(struct nss_ipv4_rule_conn_cfg_msg), nss_ipv4_conn_cfg_callback, NULL);
370
371 nirccm = &nim.msg.rule_conn_cfg;
372 nirccm->num_conn = htonl(nss_ipv4_conn_cfg);
373 nss_tx_status = nss_ipv4_tx(nss_ctx, &nim);
374
375 if (nss_tx_status != NSS_TX_SUCCESS) {
376 nss_warning("%p: nss_tx error setting IPv4 Connections: %d\n",
377 nss_ctx,
378 nss_ipv4_conn_cfg);
379 }
380 return ret;
381}
382
383static ctl_table nss_ipv4_table[] = {
384 {
385 .procname = "ipv4_conn",
386 .data = &nss_ipv4_conn_cfg,
387 .maxlen = sizeof(int),
388 .mode = 0644,
389 .proc_handler = &nss_ipv4_conn_cfg_handler,
390 },
391 { }
392};
393
394static ctl_table nss_ipv4_dir[] = {
395 {
396 .procname = "ipv4cfg",
397 .mode = 0555,
398 .child = nss_ipv4_table,
399 },
400 { }
401};
402
403
404static ctl_table nss_ipv4_root_dir[] = {
405 {
406 .procname = "nss",
407 .mode = 0555,
408 .child = nss_ipv4_dir,
409 },
410 { }
411};
412
413static ctl_table nss_ipv4_root[] = {
414 {
415 .procname = "dev",
416 .mode = 0555,
417 .child = nss_ipv4_root_dir,
418 },
419 { }
420};
421
422static struct ctl_table_header *nss_ipv4_header;
423
424/*
425 * nss_ipv4_register_sysctl()
426 * Register sysctl specific to ipv4
427 */
428void nss_ipv4_register_sysctl(void)
429{
430 /*
431 * Register sysctl table.
432 */
433 nss_ipv4_header = register_sysctl_table(nss_ipv4_root);
434}
435
436/*
437 * nss_ipv4_unregister_sysctl()
438 * Unregister sysctl specific to ipv4
439 */
440void nss_ipv4_unregister_sysctl(void)
441{
442 /*
443 * Unregister sysctl table.
444 */
445 if (nss_ipv4_header) {
446 unregister_sysctl_table(nss_ipv4_header);
447 }
448}
449
Thomas Wu68250352014-04-02 18:59:40 -0700450EXPORT_SYMBOL(nss_ipv4_tx);
451EXPORT_SYMBOL(nss_ipv4_notify_register);
452EXPORT_SYMBOL(nss_ipv4_notify_unregister);
453EXPORT_SYMBOL(nss_ipv4_get_mgr);
Vijay Dewangan9db18752014-09-15 16:25:01 -0700454EXPORT_SYMBOL(nss_ipv4_register_sysctl);
455EXPORT_SYMBOL(nss_ipv4_unregister_sysctl);