alistair23-linux/net/mac80211/mesh.c
Johannes Berg 6b86bd62a5 mac80211: mesh: move some code to make it static
There's no need to have table functions in one
file and all users in another, move the functions
to the right file and make them static. Also move
a static variable to the beginning of the file to
make it easier to find.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-05-12 14:10:55 -04:00

651 lines
19 KiB
C

/*
* Copyright (c) 2008, 2009 open80211s Ltd.
* Authors: Luis Carlos Cobo <luisca@cozybit.com>
* Javier Cardona <javier@cozybit.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/slab.h>
#include <asm/unaligned.h>
#include "ieee80211_i.h"
#include "mesh.h"
#define IEEE80211_MESH_PEER_INACTIVITY_LIMIT (1800 * HZ)
#define IEEE80211_MESH_HOUSEKEEPING_INTERVAL (60 * HZ)
#define IEEE80211_MESH_RANN_INTERVAL (1 * HZ)
#define MESHCONF_CAPAB_ACCEPT_PLINKS 0x01
#define MESHCONF_CAPAB_FORWARDING 0x08
#define TMR_RUNNING_HK 0
#define TMR_RUNNING_MP 1
#define TMR_RUNNING_MPR 2
int mesh_allocated;
static struct kmem_cache *rm_cache;
void ieee80211s_init(void)
{
mesh_pathtbl_init();
mesh_allocated = 1;
rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
0, 0, NULL);
}
void ieee80211s_stop(void)
{
mesh_pathtbl_unregister();
kmem_cache_destroy(rm_cache);
}
static void ieee80211_mesh_housekeeping_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata = (void *) data;
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
if (local->quiescing) {
set_bit(TMR_RUNNING_HK, &ifmsh->timers_running);
return;
}
ieee80211_queue_work(&local->hw, &sdata->work);
}
/**
* mesh_matches_local - check if the config of a mesh point matches ours
*
* @ie: information elements of a management frame from the mesh peer
* @sdata: local mesh subif
*
* This function checks if the mesh configuration of a mesh point matches the
* local mesh configuration, i.e. if both nodes belong to the same mesh network.
*/
bool mesh_matches_local(struct ieee802_11_elems *ie, struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
/*
* As support for each feature is added, check for matching
* - On mesh config capabilities
* - Power Save Support En
* - Sync support enabled
* - Sync support active
* - Sync support required from peer
* - MDA enabled
* - Power management control on fc
*/
if (ifmsh->mesh_id_len == ie->mesh_id_len &&
memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
(ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
(ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
(ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
(ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
(ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth))
return true;
return false;
}
/**
* mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
*
* @ie: information elements of a management frame from the mesh peer
*/
bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
{
return (ie->mesh_config->meshconf_cap &
MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
}
/**
* mesh_accept_plinks_update: update accepting_plink in local mesh beacons
*
* @sdata: mesh interface in which mesh beacons are going to be updated
*/
void mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
{
bool free_plinks;
/* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
* the mesh interface might be able to establish plinks with peers that
* are already on the table but are not on PLINK_ESTAB state. However,
* in general the mesh interface is not accepting peer link requests
* from new peers, and that must be reflected in the beacon
*/
free_plinks = mesh_plink_availables(sdata);
if (free_plinks != sdata->u.mesh.accepting_plinks)
ieee80211_mesh_housekeeping_timer((unsigned long) sdata);
}
int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
{
int i;
sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
if (!sdata->u.mesh.rmc)
return -ENOMEM;
sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
for (i = 0; i < RMC_BUCKETS; i++)
INIT_LIST_HEAD(&sdata->u.mesh.rmc->bucket[i].list);
return 0;
}
void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
{
struct mesh_rmc *rmc = sdata->u.mesh.rmc;
struct rmc_entry *p, *n;
int i;
if (!sdata->u.mesh.rmc)
return;
for (i = 0; i < RMC_BUCKETS; i++)
list_for_each_entry_safe(p, n, &rmc->bucket[i].list, list) {
list_del(&p->list);
kmem_cache_free(rm_cache, p);
}
kfree(rmc);
sdata->u.mesh.rmc = NULL;
}
/**
* mesh_rmc_check - Check frame in recent multicast cache and add if absent.
*
* @sa: source address
* @mesh_hdr: mesh_header
*
* Returns: 0 if the frame is not in the cache, nonzero otherwise.
*
* Checks using the source address and the mesh sequence number if we have
* received this frame lately. If the frame is not in the cache, it is added to
* it.
*/
int mesh_rmc_check(u8 *sa, struct ieee80211s_hdr *mesh_hdr,
struct ieee80211_sub_if_data *sdata)
{
struct mesh_rmc *rmc = sdata->u.mesh.rmc;
u32 seqnum = 0;
int entries = 0;
u8 idx;
struct rmc_entry *p, *n;
/* Don't care about endianness since only match matters */
memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
list_for_each_entry_safe(p, n, &rmc->bucket[idx].list, list) {
++entries;
if (time_after(jiffies, p->exp_time) ||
(entries == RMC_QUEUE_MAX_LEN)) {
list_del(&p->list);
kmem_cache_free(rm_cache, p);
--entries;
} else if ((seqnum == p->seqnum) &&
(memcmp(sa, p->sa, ETH_ALEN) == 0))
return -1;
}
p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
if (!p) {
printk(KERN_DEBUG "o11s: could not allocate RMC entry\n");
return 0;
}
p->seqnum = seqnum;
p->exp_time = jiffies + RMC_TIMEOUT;
memcpy(p->sa, sa, ETH_ALEN);
list_add(&p->list, &rmc->bucket[idx].list);
return 0;
}
void mesh_mgmt_ies_add(struct sk_buff *skb, struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_supported_band *sband;
u8 *pos;
int len, i, rate;
u8 neighbors;
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
len = sband->n_bitrates;
if (len > 8)
len = 8;
pos = skb_put(skb, len + 2);
*pos++ = WLAN_EID_SUPP_RATES;
*pos++ = len;
for (i = 0; i < len; i++) {
rate = sband->bitrates[i].bitrate;
*pos++ = (u8) (rate / 5);
}
if (sband->n_bitrates > len) {
pos = skb_put(skb, sband->n_bitrates - len + 2);
*pos++ = WLAN_EID_EXT_SUPP_RATES;
*pos++ = sband->n_bitrates - len;
for (i = len; i < sband->n_bitrates; i++) {
rate = sband->bitrates[i].bitrate;
*pos++ = (u8) (rate / 5);
}
}
if (sband->band == IEEE80211_BAND_2GHZ) {
pos = skb_put(skb, 2 + 1);
*pos++ = WLAN_EID_DS_PARAMS;
*pos++ = 1;
*pos++ = ieee80211_frequency_to_channel(local->hw.conf.channel->center_freq);
}
pos = skb_put(skb, 2 + sdata->u.mesh.mesh_id_len);
*pos++ = WLAN_EID_MESH_ID;
*pos++ = sdata->u.mesh.mesh_id_len;
if (sdata->u.mesh.mesh_id_len)
memcpy(pos, sdata->u.mesh.mesh_id, sdata->u.mesh.mesh_id_len);
pos = skb_put(skb, 2 + sizeof(struct ieee80211_meshconf_ie));
*pos++ = WLAN_EID_MESH_CONFIG;
*pos++ = sizeof(struct ieee80211_meshconf_ie);
/* Active path selection protocol ID */
*pos++ = sdata->u.mesh.mesh_pp_id;
/* Active path selection metric ID */
*pos++ = sdata->u.mesh.mesh_pm_id;
/* Congestion control mode identifier */
*pos++ = sdata->u.mesh.mesh_cc_id;
/* Synchronization protocol identifier */
*pos++ = sdata->u.mesh.mesh_sp_id;
/* Authentication Protocol identifier */
*pos++ = sdata->u.mesh.mesh_auth_id;
/* Mesh Formation Info - number of neighbors */
neighbors = atomic_read(&sdata->u.mesh.mshstats.estab_plinks);
/* Number of neighbor mesh STAs or 15 whichever is smaller */
neighbors = (neighbors > 15) ? 15 : neighbors;
*pos++ = neighbors << 1;
/* Mesh capability */
sdata->u.mesh.accepting_plinks = mesh_plink_availables(sdata);
*pos = MESHCONF_CAPAB_FORWARDING;
*pos++ |= sdata->u.mesh.accepting_plinks ?
MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
*pos++ = 0x00;
if (sdata->u.mesh.ie) {
int len = sdata->u.mesh.ie_len;
const u8 *data = sdata->u.mesh.ie;
if (skb_tailroom(skb) > len)
memcpy(skb_put(skb, len), data, len);
}
}
static void ieee80211_mesh_path_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata =
(struct ieee80211_sub_if_data *) data;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_local *local = sdata->local;
if (local->quiescing) {
set_bit(TMR_RUNNING_MP, &ifmsh->timers_running);
return;
}
ieee80211_queue_work(&local->hw, &sdata->work);
}
static void ieee80211_mesh_path_root_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata =
(struct ieee80211_sub_if_data *) data;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_local *local = sdata->local;
set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
if (local->quiescing) {
set_bit(TMR_RUNNING_MPR, &ifmsh->timers_running);
return;
}
ieee80211_queue_work(&local->hw, &sdata->work);
}
void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
{
if (ifmsh->mshcfg.dot11MeshHWMPRootMode)
set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
else {
clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
/* stop running timer */
del_timer_sync(&ifmsh->mesh_path_root_timer);
}
}
/**
* ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
* @hdr: 802.11 frame header
* @fc: frame control field
* @meshda: destination address in the mesh
* @meshsa: source address address in the mesh. Same as TA, as frame is
* locally originated.
*
* Return the length of the 802.11 (does not include a mesh control header)
*/
int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
const u8 *meshda, const u8 *meshsa)
{
if (is_multicast_ether_addr(meshda)) {
*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
/* DA TA SA */
memcpy(hdr->addr1, meshda, ETH_ALEN);
memcpy(hdr->addr2, meshsa, ETH_ALEN);
memcpy(hdr->addr3, meshsa, ETH_ALEN);
return 24;
} else {
*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
IEEE80211_FCTL_TODS);
/* RA TA DA SA */
memset(hdr->addr1, 0, ETH_ALEN); /* RA is resolved later */
memcpy(hdr->addr2, meshsa, ETH_ALEN);
memcpy(hdr->addr3, meshda, ETH_ALEN);
memcpy(hdr->addr4, meshsa, ETH_ALEN);
return 30;
}
}
/**
* ieee80211_new_mesh_header - create a new mesh header
* @meshhdr: uninitialized mesh header
* @sdata: mesh interface to be used
* @addr4or5: 1st address in the ae header, which may correspond to address 4
* (if addr6 is NULL) or address 5 (if addr6 is present). It may
* be NULL.
* @addr6: 2nd address in the ae header, which corresponds to addr6 of the
* mesh frame
*
* Return the header length.
*/
int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
struct ieee80211_sub_if_data *sdata, char *addr4or5,
char *addr6)
{
int aelen = 0;
BUG_ON(!addr4or5 && addr6);
memset(meshhdr, 0, sizeof(*meshhdr));
meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
sdata->u.mesh.mesh_seqnum++;
if (addr4or5 && !addr6) {
meshhdr->flags |= MESH_FLAGS_AE_A4;
aelen += ETH_ALEN;
memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
} else if (addr4or5 && addr6) {
meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
aelen += 2 * ETH_ALEN;
memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
}
return 6 + aelen;
}
static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata,
struct ieee80211_if_mesh *ifmsh)
{
bool free_plinks;
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
printk(KERN_DEBUG "%s: running mesh housekeeping\n",
sdata->name);
#endif
ieee80211_sta_expire(sdata, IEEE80211_MESH_PEER_INACTIVITY_LIMIT);
mesh_path_expire(sdata);
free_plinks = mesh_plink_availables(sdata);
if (free_plinks != sdata->u.mesh.accepting_plinks)
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
mod_timer(&ifmsh->housekeeping_timer,
round_jiffies(jiffies + IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
}
static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
mesh_path_tx_root_frame(sdata);
mod_timer(&ifmsh->mesh_path_root_timer,
round_jiffies(jiffies + IEEE80211_MESH_RANN_INTERVAL));
}
#ifdef CONFIG_PM
void ieee80211_mesh_quiesce(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
/* use atomic bitops in case both timers fire at the same time */
if (del_timer_sync(&ifmsh->housekeeping_timer))
set_bit(TMR_RUNNING_HK, &ifmsh->timers_running);
if (del_timer_sync(&ifmsh->mesh_path_timer))
set_bit(TMR_RUNNING_MP, &ifmsh->timers_running);
if (del_timer_sync(&ifmsh->mesh_path_root_timer))
set_bit(TMR_RUNNING_MPR, &ifmsh->timers_running);
}
void ieee80211_mesh_restart(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
if (test_and_clear_bit(TMR_RUNNING_HK, &ifmsh->timers_running))
add_timer(&ifmsh->housekeeping_timer);
if (test_and_clear_bit(TMR_RUNNING_MP, &ifmsh->timers_running))
add_timer(&ifmsh->mesh_path_timer);
if (test_and_clear_bit(TMR_RUNNING_MPR, &ifmsh->timers_running))
add_timer(&ifmsh->mesh_path_root_timer);
ieee80211_mesh_root_setup(ifmsh);
}
#endif
void ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_local *local = sdata->local;
local->fif_other_bss++;
/* mesh ifaces must set allmulti to forward mcast traffic */
atomic_inc(&local->iff_allmultis);
ieee80211_configure_filter(local);
ifmsh->mesh_cc_id = 0; /* Disabled */
ifmsh->mesh_sp_id = 0; /* Neighbor Offset */
ifmsh->mesh_auth_id = 0; /* Disabled */
set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
ieee80211_mesh_root_setup(ifmsh);
ieee80211_queue_work(&local->hw, &sdata->work);
sdata->vif.bss_conf.beacon_int = MESH_DEFAULT_BEACON_INTERVAL;
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON |
BSS_CHANGED_BEACON_ENABLED |
BSS_CHANGED_BEACON_INT);
}
void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
ifmsh->mesh_id_len = 0;
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
sta_info_flush(local, NULL);
del_timer_sync(&sdata->u.mesh.housekeeping_timer);
del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
/*
* If the timer fired while we waited for it, it will have
* requeued the work. Now the work will be running again
* but will not rearm the timer again because it checks
* whether the interface is running, which, at this point,
* it no longer is.
*/
cancel_work_sync(&sdata->work);
local->fif_other_bss--;
atomic_dec(&local->iff_allmultis);
ieee80211_configure_filter(local);
}
static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
u16 stype,
struct ieee80211_mgmt *mgmt,
size_t len,
struct ieee80211_rx_status *rx_status)
{
struct ieee80211_local *local = sdata->local;
struct ieee802_11_elems elems;
struct ieee80211_channel *channel;
u32 supp_rates = 0;
size_t baselen;
int freq;
enum ieee80211_band band = rx_status->band;
/* ignore ProbeResp to foreign address */
if (stype == IEEE80211_STYPE_PROBE_RESP &&
compare_ether_addr(mgmt->da, sdata->vif.addr))
return;
baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
if (baselen > len)
return;
ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
&elems);
/* ignore beacons from secure mesh peers if our security is off */
if (elems.rsn_len && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE)
return;
if (elems.ds_params && elems.ds_params_len == 1)
freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
else
freq = rx_status->freq;
channel = ieee80211_get_channel(local->hw.wiphy, freq);
if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
return;
if (elems.mesh_id && elems.mesh_config &&
mesh_matches_local(&elems, sdata)) {
supp_rates = ieee80211_sta_get_rates(local, &elems, band);
mesh_neighbour_update(mgmt->sa, supp_rates, sdata, &elems);
}
}
static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len,
struct ieee80211_rx_status *rx_status)
{
switch (mgmt->u.action.category) {
case WLAN_CATEGORY_MESH_ACTION:
mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
break;
case WLAN_CATEGORY_MESH_PATH_SEL:
mesh_rx_path_sel_frame(sdata, mgmt, len);
break;
}
}
void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_rx_status *rx_status;
struct ieee80211_mgmt *mgmt;
u16 stype;
rx_status = IEEE80211_SKB_RXCB(skb);
mgmt = (struct ieee80211_mgmt *) skb->data;
stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
switch (stype) {
case IEEE80211_STYPE_PROBE_RESP:
case IEEE80211_STYPE_BEACON:
ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
rx_status);
break;
case IEEE80211_STYPE_ACTION:
ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
break;
}
}
void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
if (ifmsh->preq_queue_len &&
time_after(jiffies,
ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
mesh_path_start_discovery(sdata);
if (test_and_clear_bit(MESH_WORK_GROW_MPATH_TABLE, &ifmsh->wrkq_flags))
mesh_mpath_table_grow();
if (test_and_clear_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags))
mesh_mpp_table_grow();
if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
ieee80211_mesh_housekeeping(sdata, ifmsh);
if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
ieee80211_mesh_rootpath(sdata);
}
void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;
rcu_read_lock();
list_for_each_entry_rcu(sdata, &local->interfaces, list)
if (ieee80211_vif_is_mesh(&sdata->vif))
ieee80211_queue_work(&local->hw, &sdata->work);
rcu_read_unlock();
}
void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
setup_timer(&ifmsh->housekeeping_timer,
ieee80211_mesh_housekeeping_timer,
(unsigned long) sdata);
ifmsh->accepting_plinks = true;
ifmsh->preq_id = 0;
ifmsh->sn = 0;
atomic_set(&ifmsh->mpaths, 0);
mesh_rmc_init(sdata);
ifmsh->last_preq = jiffies;
/* Allocate all mesh structures when creating the first mesh interface. */
if (!mesh_allocated)
ieee80211s_init();
setup_timer(&ifmsh->mesh_path_timer,
ieee80211_mesh_path_timer,
(unsigned long) sdata);
setup_timer(&ifmsh->mesh_path_root_timer,
ieee80211_mesh_path_root_timer,
(unsigned long) sdata);
INIT_LIST_HEAD(&ifmsh->preq_queue.list);
spin_lock_init(&ifmsh->mesh_preq_queue_lock);
}