linux/net/mac80211/mesh_hwmp.c

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/*
* Copyright (c) 2008, 2009 open80211s Ltd.
* Author: Luis Carlos Cobo <luisca@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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include "wme.h"
#include "mesh.h"
#ifdef CONFIG_MAC80211_VERBOSE_MHWMP_DEBUG
#define mhwmp_dbg(fmt, args...) \
printk(KERN_DEBUG "Mesh HWMP (%s): " fmt "\n", sdata->name, ##args)
#else
#define mhwmp_dbg(fmt, args...) do { (void)(0); } while (0)
#endif
#define TEST_FRAME_LEN 8192
#define MAX_METRIC 0xffffffff
#define ARITH_SHIFT 8
/* Number of frames buffered per destination for unresolved destinations */
#define MESH_FRAME_QUEUE_LEN 10
#define MAX_PREQ_QUEUE_LEN 64
/* Destination only */
#define MP_F_DO 0x1
/* Reply and forward */
#define MP_F_RF 0x2
/* Unknown Sequence Number */
#define MP_F_USN 0x01
/* Reason code Present */
#define MP_F_RCODE 0x02
static void mesh_queue_preq(struct mesh_path *, u8);
static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae)
{
if (ae)
offset += 6;
return get_unaligned_le32(preq_elem + offset);
}
static inline u32 u16_field_get(u8 *preq_elem, int offset, bool ae)
{
if (ae)
offset += 6;
return get_unaligned_le16(preq_elem + offset);
}
/* HWMP IE processing macros */
#define AE_F (1<<6)
#define AE_F_SET(x) (*x & AE_F)
#define PREQ_IE_FLAGS(x) (*(x))
#define PREQ_IE_HOPCOUNT(x) (*(x + 1))
#define PREQ_IE_TTL(x) (*(x + 2))
#define PREQ_IE_PREQ_ID(x) u32_field_get(x, 3, 0)
#define PREQ_IE_ORIG_ADDR(x) (x + 7)
#define PREQ_IE_ORIG_SN(x) u32_field_get(x, 13, 0)
#define PREQ_IE_LIFETIME(x) u32_field_get(x, 17, AE_F_SET(x))
#define PREQ_IE_METRIC(x) u32_field_get(x, 21, AE_F_SET(x))
#define PREQ_IE_TARGET_F(x) (*(AE_F_SET(x) ? x + 32 : x + 26))
#define PREQ_IE_TARGET_ADDR(x) (AE_F_SET(x) ? x + 33 : x + 27)
#define PREQ_IE_TARGET_SN(x) u32_field_get(x, 33, AE_F_SET(x))
#define PREP_IE_FLAGS(x) PREQ_IE_FLAGS(x)
#define PREP_IE_HOPCOUNT(x) PREQ_IE_HOPCOUNT(x)
#define PREP_IE_TTL(x) PREQ_IE_TTL(x)
#define PREP_IE_ORIG_ADDR(x) (AE_F_SET(x) ? x + 27 : x + 21)
#define PREP_IE_ORIG_SN(x) u32_field_get(x, 27, AE_F_SET(x))
#define PREP_IE_LIFETIME(x) u32_field_get(x, 13, AE_F_SET(x))
#define PREP_IE_METRIC(x) u32_field_get(x, 17, AE_F_SET(x))
#define PREP_IE_TARGET_ADDR(x) (x + 3)
#define PREP_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
#define PERR_IE_TTL(x) (*(x))
#define PERR_IE_TARGET_FLAGS(x) (*(x + 2))
#define PERR_IE_TARGET_ADDR(x) (x + 3)
#define PERR_IE_TARGET_SN(x) u32_field_get(x, 9, 0)
#define PERR_IE_TARGET_RCODE(x) u16_field_get(x, 13, 0)
#define MSEC_TO_TU(x) (x*1000/1024)
#define SN_GT(x, y) ((long) (y) - (long) (x) < 0)
#define SN_LT(x, y) ((long) (x) - (long) (y) < 0)
#define net_traversal_jiffies(s) \
msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPnetDiameterTraversalTime)
#define default_lifetime(s) \
MSEC_TO_TU(s->u.mesh.mshcfg.dot11MeshHWMPactivePathTimeout)
#define min_preq_int_jiff(s) \
(msecs_to_jiffies(s->u.mesh.mshcfg.dot11MeshHWMPpreqMinInterval))
#define max_preq_retries(s) (s->u.mesh.mshcfg.dot11MeshHWMPmaxPREQretries)
#define disc_timeout_jiff(s) \
msecs_to_jiffies(sdata->u.mesh.mshcfg.min_discovery_timeout)
enum mpath_frame_type {
MPATH_PREQ = 0,
MPATH_PREP,
MPATH_PERR,
MPATH_RANN
};
static const u8 broadcast_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
u8 *orig_addr, __le32 orig_sn, u8 target_flags, u8 *target,
__le32 target_sn, const u8 *da, u8 hop_count, u8 ttl,
__le32 lifetime, __le32 metric, __le32 preq_id,
struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb;
struct ieee80211_mgmt *mgmt;
u8 *pos, ie_len;
int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
sizeof(mgmt->u.action.u.mesh_action);
skb = dev_alloc_skb(local->hw.extra_tx_headroom +
hdr_len +
2 + 37); /* max HWMP IE */
if (!skb)
return -1;
skb_reserve(skb, local->hw.extra_tx_headroom);
mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
memset(mgmt, 0, hdr_len);
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_ACTION);
memcpy(mgmt->da, da, ETH_ALEN);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
/* BSSID == SA */
memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
mgmt->u.action.u.mesh_action.action_code =
WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
switch (action) {
case MPATH_PREQ:
mhwmp_dbg("sending PREQ to %pM", target);
ie_len = 37;
pos = skb_put(skb, 2 + ie_len);
*pos++ = WLAN_EID_PREQ;
break;
case MPATH_PREP:
mhwmp_dbg("sending PREP to %pM", target);
ie_len = 31;
pos = skb_put(skb, 2 + ie_len);
*pos++ = WLAN_EID_PREP;
break;
case MPATH_RANN:
mhwmp_dbg("sending RANN from %pM", orig_addr);
ie_len = sizeof(struct ieee80211_rann_ie);
pos = skb_put(skb, 2 + ie_len);
*pos++ = WLAN_EID_RANN;
break;
default:
kfree_skb(skb);
return -ENOTSUPP;
break;
}
*pos++ = ie_len;
*pos++ = flags;
*pos++ = hop_count;
*pos++ = ttl;
if (action == MPATH_PREP) {
memcpy(pos, target, ETH_ALEN);
pos += ETH_ALEN;
memcpy(pos, &target_sn, 4);
pos += 4;
} else {
if (action == MPATH_PREQ) {
memcpy(pos, &preq_id, 4);
pos += 4;
}
memcpy(pos, orig_addr, ETH_ALEN);
pos += ETH_ALEN;
memcpy(pos, &orig_sn, 4);
pos += 4;
}
memcpy(pos, &lifetime, 4); /* interval for RANN */
pos += 4;
memcpy(pos, &metric, 4);
pos += 4;
if (action == MPATH_PREQ) {
*pos++ = 1; /* destination count */
*pos++ = target_flags;
memcpy(pos, target, ETH_ALEN);
pos += ETH_ALEN;
memcpy(pos, &target_sn, 4);
pos += 4;
} else if (action == MPATH_PREP) {
memcpy(pos, orig_addr, ETH_ALEN);
pos += ETH_ALEN;
memcpy(pos, &orig_sn, 4);
pos += 4;
}
ieee80211_tx_skb(sdata, skb);
return 0;
}
/* Headroom is not adjusted. Caller should ensure that skb has sufficient
* headroom in case the frame is encrypted. */
static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
skb_set_mac_header(skb, 0);
skb_set_network_header(skb, 0);
skb_set_transport_header(skb, 0);
/* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
skb_set_queue_mapping(skb, IEEE80211_AC_VO);
skb->priority = 7;
info->control.vif = &sdata->vif;
ieee80211_set_qos_hdr(sdata, skb);
}
/**
* mesh_send_path error - Sends a PERR mesh management frame
*
* @target: broken destination
* @target_sn: SN of the broken destination
* @target_rcode: reason code for this PERR
* @ra: node this frame is addressed to
*
* Note: This function may be called with driver locks taken that the driver
* also acquires in the TX path. To avoid a deadlock we don't transmit the
* frame directly but add it to the pending queue instead.
*/
int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn,
__le16 target_rcode, const u8 *ra,
struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct ieee80211_mgmt *mgmt;
u8 *pos, ie_len;
int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
sizeof(mgmt->u.action.u.mesh_action);
if (time_before(jiffies, ifmsh->next_perr))
return -EAGAIN;
skb = dev_alloc_skb(local->hw.extra_tx_headroom +
hdr_len +
2 + 15 /* PERR IE */);
if (!skb)
return -1;
skb_reserve(skb, local->tx_headroom + local->hw.extra_tx_headroom);
mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
memset(mgmt, 0, hdr_len);
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_ACTION);
memcpy(mgmt->da, ra, ETH_ALEN);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
/* BSSID == SA */
memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION;
mgmt->u.action.u.mesh_action.action_code =
WLAN_MESH_ACTION_HWMP_PATH_SELECTION;
ie_len = 15;
pos = skb_put(skb, 2 + ie_len);
*pos++ = WLAN_EID_PERR;
*pos++ = ie_len;
/* ttl */
*pos++ = ttl;
/* number of destinations */
*pos++ = 1;
/*
* flags bit, bit 1 is unset if we know the sequence number and
* bit 2 is set if we have a reason code
*/
*pos = 0;
if (!target_sn)
*pos |= MP_F_USN;
if (target_rcode)
*pos |= MP_F_RCODE;
pos++;
memcpy(pos, target, ETH_ALEN);
pos += ETH_ALEN;
memcpy(pos, &target_sn, 4);
pos += 4;
memcpy(pos, &target_rcode, 2);
/* see note in function header */
prepare_frame_for_deferred_tx(sdata, skb);
ifmsh->next_perr = TU_TO_EXP_TIME(
ifmsh->mshcfg.dot11MeshHWMPperrMinInterval);
ieee80211_add_pending_skb(local, skb);
return 0;
}
void ieee80211s_update_metric(struct ieee80211_local *local,
struct sta_info *stainfo, struct sk_buff *skb)
{
struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
int failed;
if (!ieee80211_is_data(hdr->frame_control))
return;
failed = !(txinfo->flags & IEEE80211_TX_STAT_ACK);
/* moving average, scaled to 100 */
stainfo->fail_avg = ((80 * stainfo->fail_avg + 5) / 100 + 20 * failed);
if (stainfo->fail_avg > 95)
mesh_plink_broken(stainfo);
}
static u32 airtime_link_metric_get(struct ieee80211_local *local,
struct sta_info *sta)
{
struct ieee80211_supported_band *sband;
/* This should be adjusted for each device */
int device_constant = 1 << ARITH_SHIFT;
int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT;
int s_unit = 1 << ARITH_SHIFT;
int rate, err;
u32 tx_time, estimated_retx;
u64 result;
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
if (sta->fail_avg >= 100)
return MAX_METRIC;
if (sta->last_tx_rate.flags & IEEE80211_TX_RC_MCS)
return MAX_METRIC;
err = (sta->fail_avg << ARITH_SHIFT) / 100;
/* bitrate is in units of 100 Kbps, while we need rate in units of
* 1Mbps. This will be corrected on tx_time computation.
*/
rate = sband->bitrates[sta->last_tx_rate.idx].bitrate;
tx_time = (device_constant + 10 * test_frame_len / rate);
estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err));
result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ;
return (u32)result;
}
/**
* hwmp_route_info_get - Update routing info to originator and transmitter
*
* @sdata: local mesh subif
* @mgmt: mesh management frame
* @hwmp_ie: hwmp information element (PREP or PREQ)
*
* This function updates the path routing information to the originator and the
* transmitter of a HWMP PREQ or PREP frame.
*
* Returns: metric to frame originator or 0 if the frame should not be further
* processed
*
* Notes: this function is the only place (besides user-provided info) where
* path routing information is updated.
*/
static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
u8 *hwmp_ie, enum mpath_frame_type action)
{
struct ieee80211_local *local = sdata->local;
struct mesh_path *mpath;
struct sta_info *sta;
bool fresh_info;
u8 *orig_addr, *ta;
u32 orig_sn, orig_metric;
unsigned long orig_lifetime, exp_time;
u32 last_hop_metric, new_metric;
bool process = true;
rcu_read_lock();
sta = sta_info_get(sdata, mgmt->sa);
if (!sta) {
rcu_read_unlock();
return 0;
}
last_hop_metric = airtime_link_metric_get(local, sta);
/* Update and check originator routing info */
fresh_info = true;
switch (action) {
case MPATH_PREQ:
orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie);
orig_sn = PREQ_IE_ORIG_SN(hwmp_ie);
orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie);
orig_metric = PREQ_IE_METRIC(hwmp_ie);
break;
case MPATH_PREP:
/* Originator here refers to the MP that was the target in the
* Path Request. We divert from the nomenclature in the draft
* so that we can easily use a single function to gather path
* information from both PREQ and PREP frames.
*/
orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie);
orig_sn = PREP_IE_TARGET_SN(hwmp_ie);
orig_lifetime = PREP_IE_LIFETIME(hwmp_ie);
orig_metric = PREP_IE_METRIC(hwmp_ie);
break;
default:
rcu_read_unlock();
return 0;
}
new_metric = orig_metric + last_hop_metric;
if (new_metric < orig_metric)
new_metric = MAX_METRIC;
exp_time = TU_TO_EXP_TIME(orig_lifetime);
if (memcmp(orig_addr, sdata->vif.addr, ETH_ALEN) == 0) {
/* This MP is the originator, we are not interested in this
* frame, except for updating transmitter's path info.
*/
process = false;
fresh_info = false;
} else {
mpath = mesh_path_lookup(orig_addr, sdata);
if (mpath) {
spin_lock_bh(&mpath->state_lock);
if (mpath->flags & MESH_PATH_FIXED)
fresh_info = false;
else if ((mpath->flags & MESH_PATH_ACTIVE) &&
(mpath->flags & MESH_PATH_SN_VALID)) {
if (SN_GT(mpath->sn, orig_sn) ||
(mpath->sn == orig_sn &&
new_metric >= mpath->metric)) {
process = false;
fresh_info = false;
}
}
} else {
mesh_path_add(orig_addr, sdata);
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
rcu_read_unlock();
return 0;
}
spin_lock_bh(&mpath->state_lock);
}
if (fresh_info) {
mesh_path_assign_nexthop(mpath, sta);
mpath->flags |= MESH_PATH_SN_VALID;
mpath->metric = new_metric;
mpath->sn = orig_sn;
mpath->exp_time = time_after(mpath->exp_time, exp_time)
? mpath->exp_time : exp_time;
mesh_path_activate(mpath);
spin_unlock_bh(&mpath->state_lock);
mesh_path_tx_pending(mpath);
/* draft says preq_id should be saved to, but there does
* not seem to be any use for it, skipping by now
*/
} else
spin_unlock_bh(&mpath->state_lock);
}
/* Update and check transmitter routing info */
ta = mgmt->sa;
if (memcmp(orig_addr, ta, ETH_ALEN) == 0)
fresh_info = false;
else {
fresh_info = true;
mpath = mesh_path_lookup(ta, sdata);
if (mpath) {
spin_lock_bh(&mpath->state_lock);
if ((mpath->flags & MESH_PATH_FIXED) ||
((mpath->flags & MESH_PATH_ACTIVE) &&
(last_hop_metric > mpath->metric)))
fresh_info = false;
} else {
mesh_path_add(ta, sdata);
mpath = mesh_path_lookup(ta, sdata);
if (!mpath) {
rcu_read_unlock();
return 0;
}
spin_lock_bh(&mpath->state_lock);
}
if (fresh_info) {
mesh_path_assign_nexthop(mpath, sta);
mpath->metric = last_hop_metric;
mpath->exp_time = time_after(mpath->exp_time, exp_time)
? mpath->exp_time : exp_time;
mesh_path_activate(mpath);
spin_unlock_bh(&mpath->state_lock);
mesh_path_tx_pending(mpath);
} else
spin_unlock_bh(&mpath->state_lock);
}
rcu_read_unlock();
return process ? new_metric : 0;
}
static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
u8 *preq_elem, u32 metric)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_path *mpath;
u8 *target_addr, *orig_addr;
u8 target_flags, ttl;
u32 orig_sn, target_sn, lifetime;
bool reply = false;
bool forward = true;
/* Update target SN, if present */
target_addr = PREQ_IE_TARGET_ADDR(preq_elem);
orig_addr = PREQ_IE_ORIG_ADDR(preq_elem);
target_sn = PREQ_IE_TARGET_SN(preq_elem);
orig_sn = PREQ_IE_ORIG_SN(preq_elem);
target_flags = PREQ_IE_TARGET_F(preq_elem);
mhwmp_dbg("received PREQ from %pM", orig_addr);
if (memcmp(target_addr, sdata->vif.addr, ETH_ALEN) == 0) {
mhwmp_dbg("PREQ is for us");
forward = false;
reply = true;
metric = 0;
if (time_after(jiffies, ifmsh->last_sn_update +
net_traversal_jiffies(sdata)) ||
time_before(jiffies, ifmsh->last_sn_update)) {
target_sn = ++ifmsh->sn;
ifmsh->last_sn_update = jiffies;
}
} else {
rcu_read_lock();
mpath = mesh_path_lookup(target_addr, sdata);
if (mpath) {
if ((!(mpath->flags & MESH_PATH_SN_VALID)) ||
SN_LT(mpath->sn, target_sn)) {
mpath->sn = target_sn;
mpath->flags |= MESH_PATH_SN_VALID;
} else if ((!(target_flags & MP_F_DO)) &&
(mpath->flags & MESH_PATH_ACTIVE)) {
reply = true;
metric = mpath->metric;
target_sn = mpath->sn;
if (target_flags & MP_F_RF)
target_flags |= MP_F_DO;
else
forward = false;
}
}
rcu_read_unlock();
}
if (reply) {
lifetime = PREQ_IE_LIFETIME(preq_elem);
ttl = ifmsh->mshcfg.element_ttl;
if (ttl != 0) {
mhwmp_dbg("replying to the PREQ");
mesh_path_sel_frame_tx(MPATH_PREP, 0, orig_addr,
cpu_to_le32(orig_sn), 0, target_addr,
cpu_to_le32(target_sn), mgmt->sa, 0, ttl,
cpu_to_le32(lifetime), cpu_to_le32(metric),
0, sdata);
} else
ifmsh->mshstats.dropped_frames_ttl++;
}
if (forward) {
u32 preq_id;
u8 hopcount, flags;
ttl = PREQ_IE_TTL(preq_elem);
lifetime = PREQ_IE_LIFETIME(preq_elem);
if (ttl <= 1) {
ifmsh->mshstats.dropped_frames_ttl++;
return;
}
mhwmp_dbg("forwarding the PREQ from %pM", orig_addr);
--ttl;
flags = PREQ_IE_FLAGS(preq_elem);
preq_id = PREQ_IE_PREQ_ID(preq_elem);
hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
cpu_to_le32(orig_sn), target_flags, target_addr,
cpu_to_le32(target_sn), broadcast_addr,
hopcount, ttl, cpu_to_le32(lifetime),
cpu_to_le32(metric), cpu_to_le32(preq_id),
sdata);
ifmsh->mshstats.fwded_mcast++;
ifmsh->mshstats.fwded_frames++;
}
}
static inline struct sta_info *
next_hop_deref_protected(struct mesh_path *mpath)
{
return rcu_dereference_protected(mpath->next_hop,
lockdep_is_held(&mpath->state_lock));
}
static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
u8 *prep_elem, u32 metric)
{
struct mesh_path *mpath;
u8 *target_addr, *orig_addr;
u8 ttl, hopcount, flags;
u8 next_hop[ETH_ALEN];
u32 target_sn, orig_sn, lifetime;
mhwmp_dbg("received PREP from %pM", PREP_IE_ORIG_ADDR(prep_elem));
orig_addr = PREP_IE_ORIG_ADDR(prep_elem);
if (memcmp(orig_addr, sdata->vif.addr, ETH_ALEN) == 0)
/* destination, no forwarding required */
return;
ttl = PREP_IE_TTL(prep_elem);
if (ttl <= 1) {
sdata->u.mesh.mshstats.dropped_frames_ttl++;
return;
}
rcu_read_lock();
mpath = mesh_path_lookup(orig_addr, sdata);
if (mpath)
spin_lock_bh(&mpath->state_lock);
else
goto fail;
if (!(mpath->flags & MESH_PATH_ACTIVE)) {
spin_unlock_bh(&mpath->state_lock);
goto fail;
}
memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
spin_unlock_bh(&mpath->state_lock);
--ttl;
flags = PREP_IE_FLAGS(prep_elem);
lifetime = PREP_IE_LIFETIME(prep_elem);
hopcount = PREP_IE_HOPCOUNT(prep_elem) + 1;
target_addr = PREP_IE_TARGET_ADDR(prep_elem);
target_sn = PREP_IE_TARGET_SN(prep_elem);
orig_sn = PREP_IE_ORIG_SN(prep_elem);
mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
cpu_to_le32(orig_sn), 0, target_addr,
cpu_to_le32(target_sn), next_hop, hopcount,
ttl, cpu_to_le32(lifetime), cpu_to_le32(metric),
0, sdata);
rcu_read_unlock();
sdata->u.mesh.mshstats.fwded_unicast++;
sdata->u.mesh.mshstats.fwded_frames++;
return;
fail:
rcu_read_unlock();
sdata->u.mesh.mshstats.dropped_frames_no_route++;
}
static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt, u8 *perr_elem)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_path *mpath;
u8 ttl;
u8 *ta, *target_addr;
u32 target_sn;
u16 target_rcode;
ta = mgmt->sa;
ttl = PERR_IE_TTL(perr_elem);
if (ttl <= 1) {
ifmsh->mshstats.dropped_frames_ttl++;
return;
}
ttl--;
target_addr = PERR_IE_TARGET_ADDR(perr_elem);
target_sn = PERR_IE_TARGET_SN(perr_elem);
target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
rcu_read_lock();
mpath = mesh_path_lookup(target_addr, sdata);
if (mpath) {
spin_lock_bh(&mpath->state_lock);
if (mpath->flags & MESH_PATH_ACTIVE &&
memcmp(ta, next_hop_deref_protected(mpath)->sta.addr,
ETH_ALEN) == 0 &&
(!(mpath->flags & MESH_PATH_SN_VALID) ||
SN_GT(target_sn, mpath->sn))) {
mpath->flags &= ~MESH_PATH_ACTIVE;
mpath->sn = target_sn;
spin_unlock_bh(&mpath->state_lock);
mesh_path_error_tx(ttl, target_addr, cpu_to_le32(target_sn),
cpu_to_le16(target_rcode),
broadcast_addr, sdata);
} else
spin_unlock_bh(&mpath->state_lock);
}
rcu_read_unlock();
}
static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
struct ieee80211_rann_ie *rann)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_path *mpath;
u8 ttl, flags, hopcount;
u8 *orig_addr;
u32 orig_sn, metric;
u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
bool root_is_gate;
ttl = rann->rann_ttl;
if (ttl <= 1) {
ifmsh->mshstats.dropped_frames_ttl++;
return;
}
ttl--;
flags = rann->rann_flags;
root_is_gate = !!(flags & RANN_FLAG_IS_GATE);
orig_addr = rann->rann_addr;
orig_sn = rann->rann_seq;
hopcount = rann->rann_hopcount;
hopcount++;
metric = rann->rann_metric;
/* Ignore our own RANNs */
if (memcmp(orig_addr, sdata->vif.addr, ETH_ALEN) == 0)
return;
mhwmp_dbg("received RANN from %pM (is_gate=%d)", orig_addr,
root_is_gate);
rcu_read_lock();
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
mesh_path_add(orig_addr, sdata);
mpath = mesh_path_lookup(orig_addr, sdata);
if (!mpath) {
rcu_read_unlock();
sdata->u.mesh.mshstats.dropped_frames_no_route++;
return;
}
}
if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) ||
time_after(jiffies, mpath->exp_time - 1*HZ)) &&
!(mpath->flags & MESH_PATH_FIXED)) {
mhwmp_dbg("%s time to refresh root mpath %pM", sdata->name,
orig_addr);
mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH);
}
if (mpath->sn < orig_sn) {
mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
cpu_to_le32(orig_sn),
0, NULL, 0, broadcast_addr,
hopcount, ttl, cpu_to_le32(interval),
cpu_to_le32(metric + mpath->metric),
0, sdata);
mpath->sn = orig_sn;
}
if (root_is_gate)
mesh_path_add_gate(mpath);
rcu_read_unlock();
}
void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len)
{
struct ieee802_11_elems elems;
size_t baselen;
u32 last_hop_metric;
struct sta_info *sta;
/* need action_code */
if (len < IEEE80211_MIN_ACTION_SIZE + 1)
return;
rcu_read_lock();
sta = sta_info_get(sdata, mgmt->sa);
if (!sta || sta->plink_state != NL80211_PLINK_ESTAB) {
rcu_read_unlock();
return;
}
rcu_read_unlock();
baselen = (u8 *) mgmt->u.action.u.mesh_action.variable - (u8 *) mgmt;
ieee802_11_parse_elems(mgmt->u.action.u.mesh_action.variable,
len - baselen, &elems);
if (elems.preq) {
if (elems.preq_len != 37)
/* Right now we support just 1 destination and no AE */
return;
last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.preq,
MPATH_PREQ);
if (last_hop_metric)
hwmp_preq_frame_process(sdata, mgmt, elems.preq,
last_hop_metric);
}
if (elems.prep) {
if (elems.prep_len != 31)
/* Right now we support no AE */
return;
last_hop_metric = hwmp_route_info_get(sdata, mgmt, elems.prep,
MPATH_PREP);
if (last_hop_metric)
hwmp_prep_frame_process(sdata, mgmt, elems.prep,
last_hop_metric);
}
if (elems.perr) {
if (elems.perr_len != 15)
/* Right now we support only one destination per PERR */
return;
hwmp_perr_frame_process(sdata, mgmt, elems.perr);
}
if (elems.rann)
hwmp_rann_frame_process(sdata, mgmt, elems.rann);
}
/**
* mesh_queue_preq - queue a PREQ to a given destination
*
* @mpath: mesh path to discover
* @flags: special attributes of the PREQ to be sent
*
* Locking: the function must be called from within a rcu read lock block.
*
*/
static void mesh_queue_preq(struct mesh_path *mpath, u8 flags)
{
struct ieee80211_sub_if_data *sdata = mpath->sdata;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_preq_queue *preq_node;
mac80211: fix allocation in mesh_queue_preq We allocate a PREQ queue node in mesh_queue_preq, however the allocation may cause us to sleep. Use GFP_ATOMIC to prevent this. [ 1869.126498] BUG: scheduling while atomic: ping/1859/0x10000100 [ 1869.127164] Modules linked in: ath5k mac80211 ath [ 1869.128310] Pid: 1859, comm: ping Not tainted 2.6.30-wl #1 [ 1869.128754] Call Trace: [ 1869.129293] [<c1023a2b>] __schedule_bug+0x48/0x4d [ 1869.129866] [<c13b5533>] __schedule+0x77/0x67a [ 1869.130544] [<c1026f2e>] ? release_console_sem+0x17d/0x185 [ 1869.131568] [<c807cf47>] ? mesh_queue_preq+0x2b/0x165 [mac80211] [ 1869.132318] [<c13b5b3e>] schedule+0x8/0x1f [ 1869.132807] [<c1023c12>] __cond_resched+0x16/0x2f [ 1869.133478] [<c13b5bf0>] _cond_resched+0x27/0x32 [ 1869.134191] [<c108a370>] kmem_cache_alloc+0x1c/0xcf [ 1869.134714] [<c10273ae>] ? printk+0x15/0x17 [ 1869.135670] [<c807cf47>] mesh_queue_preq+0x2b/0x165 [mac80211] [ 1869.136731] [<c807d1f8>] mesh_nexthop_lookup+0xee/0x12d [mac80211] [ 1869.138130] [<c807417e>] ieee80211_xmit+0xe6/0x2b2 [mac80211] [ 1869.138935] [<c80be46d>] ? ath5k_hw_setup_rx_desc+0x0/0x66 [ath5k] [ 1869.139831] [<c80c97bc>] ? ath5k_tasklet_rx+0xba/0x506 [ath5k] [ 1869.140863] [<c8075191>] ieee80211_subif_start_xmit+0x6c9/0x6e4 [mac80211] [ 1869.141665] [<c105cf1c>] ? handle_level_irq+0x78/0x9d [ 1869.142390] [<c12e3f93>] dev_hard_start_xmit+0x168/0x1c7 [ 1869.143092] [<c12f1f17>] __qdisc_run+0xe1/0x1b7 [ 1869.143612] [<c12e25ff>] qdisc_run+0x18/0x1a [ 1869.144248] [<c12e62f4>] dev_queue_xmit+0x16a/0x25a [ 1869.144785] [<c13b6dcc>] ? _read_unlock_bh+0xe/0x10 [ 1869.145465] [<c12eacdb>] neigh_resolve_output+0x19c/0x1c7 [ 1869.146182] [<c130e2da>] ? ip_finish_output+0x0/0x51 [ 1869.146697] [<c130e2a0>] ip_finish_output2+0x182/0x1bc [ 1869.147358] [<c130e327>] ip_finish_output+0x4d/0x51 [ 1869.147863] [<c130e9d5>] ip_output+0x80/0x85 [ 1869.148515] [<c130cc49>] dst_output+0x9/0xb [ 1869.149141] [<c130dec6>] ip_local_out+0x17/0x1a [ 1869.149632] [<c130e0bc>] ip_push_pending_frames+0x1f3/0x255 [ 1869.150343] [<c13247ff>] raw_sendmsg+0x5e6/0x667 [ 1869.150883] [<c1033c55>] ? insert_work+0x6a/0x73 [ 1869.151834] [<c8071e00>] ? ieee80211_invoke_rx_handlers+0x17da/0x1ae8 [mac80211] [ 1869.152630] [<c132bd68>] inet_sendmsg+0x3b/0x48 [ 1869.153232] [<c12d7deb>] __sock_sendmsg+0x45/0x4e [ 1869.153740] [<c12d8537>] sock_sendmsg+0xb8/0xce [ 1869.154519] [<c80be46d>] ? ath5k_hw_setup_rx_desc+0x0/0x66 [ath5k] [ 1869.155289] [<c1036b25>] ? autoremove_wake_function+0x0/0x30 [ 1869.155859] [<c115992b>] ? __copy_from_user_ll+0x11/0xce [ 1869.156573] [<c1159d99>] ? copy_from_user+0x31/0x54 [ 1869.157235] [<c12df646>] ? verify_iovec+0x40/0x6e [ 1869.157778] [<c12d869a>] sys_sendmsg+0x14d/0x1a5 [ 1869.158714] [<c8072c40>] ? __ieee80211_rx+0x49e/0x4ee [mac80211] [ 1869.159641] [<c80c83fe>] ? ath5k_rxbuf_setup+0x6d/0x8d [ath5k] [ 1869.160543] [<c80be46d>] ? ath5k_hw_setup_rx_desc+0x0/0x66 [ath5k] [ 1869.161434] [<c80beba4>] ? ath5k_hw_get_rxdp+0xe/0x10 [ath5k] [ 1869.162319] [<c80c97bc>] ? ath5k_tasklet_rx+0xba/0x506 [ath5k] [ 1869.163063] [<c1005627>] ? enable_8259A_irq+0x40/0x43 [ 1869.163594] [<c101edb8>] ? __dequeue_entity+0x23/0x27 [ 1869.164793] [<c100187a>] ? __switch_to+0x2b/0x105 [ 1869.165442] [<c1021d5f>] ? finish_task_switch+0x5b/0x74 [ 1869.166129] [<c12d963a>] sys_socketcall+0x14b/0x17b [ 1869.166612] [<c1002b95>] syscall_call+0x7/0xb Signed-off-by: Andrey Yurovsky <andrey@cozybit.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-06-25 23:07:42 +00:00
preq_node = kmalloc(sizeof(struct mesh_preq_queue), GFP_ATOMIC);
if (!preq_node) {
mhwmp_dbg("could not allocate PREQ node");
return;
}
spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
if (ifmsh->preq_queue_len == MAX_PREQ_QUEUE_LEN) {
spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
kfree(preq_node);
if (printk_ratelimit())
mhwmp_dbg("PREQ node queue full");
return;
}
spin_lock(&mpath->state_lock);
if (mpath->flags & MESH_PATH_REQ_QUEUED) {
spin_unlock(&mpath->state_lock);
spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
kfree(preq_node);
return;
}
memcpy(preq_node->dst, mpath->dst, ETH_ALEN);
preq_node->flags = flags;
mpath->flags |= MESH_PATH_REQ_QUEUED;
spin_unlock(&mpath->state_lock);
list_add_tail(&preq_node->list, &ifmsh->preq_queue.list);
++ifmsh->preq_queue_len;
spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
if (time_after(jiffies, ifmsh->last_preq + min_preq_int_jiff(sdata)))
ieee80211_queue_work(&sdata->local->hw, &sdata->work);
else if (time_before(jiffies, ifmsh->last_preq)) {
/* avoid long wait if did not send preqs for a long time
* and jiffies wrapped around
*/
ifmsh->last_preq = jiffies - min_preq_int_jiff(sdata) - 1;
ieee80211_queue_work(&sdata->local->hw, &sdata->work);
} else
mod_timer(&ifmsh->mesh_path_timer, ifmsh->last_preq +
min_preq_int_jiff(sdata));
}
/**
* mesh_path_start_discovery - launch a path discovery from the PREQ queue
*
* @sdata: local mesh subif
*/
void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_preq_queue *preq_node;
struct mesh_path *mpath;
u8 ttl, target_flags;
u32 lifetime;
spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
if (!ifmsh->preq_queue_len ||
time_before(jiffies, ifmsh->last_preq +
min_preq_int_jiff(sdata))) {
spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
return;
}
preq_node = list_first_entry(&ifmsh->preq_queue.list,
struct mesh_preq_queue, list);
list_del(&preq_node->list);
--ifmsh->preq_queue_len;
spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
rcu_read_lock();
mpath = mesh_path_lookup(preq_node->dst, sdata);
if (!mpath)
goto enddiscovery;
spin_lock_bh(&mpath->state_lock);
mpath->flags &= ~MESH_PATH_REQ_QUEUED;
if (preq_node->flags & PREQ_Q_F_START) {
if (mpath->flags & MESH_PATH_RESOLVING) {
spin_unlock_bh(&mpath->state_lock);
goto enddiscovery;
} else {
mpath->flags &= ~MESH_PATH_RESOLVED;
mpath->flags |= MESH_PATH_RESOLVING;
mpath->discovery_retries = 0;
mpath->discovery_timeout = disc_timeout_jiff(sdata);
}
} else if (!(mpath->flags & MESH_PATH_RESOLVING) ||
mpath->flags & MESH_PATH_RESOLVED) {
mpath->flags &= ~MESH_PATH_RESOLVING;
spin_unlock_bh(&mpath->state_lock);
goto enddiscovery;
}
ifmsh->last_preq = jiffies;
if (time_after(jiffies, ifmsh->last_sn_update +
net_traversal_jiffies(sdata)) ||
time_before(jiffies, ifmsh->last_sn_update)) {
++ifmsh->sn;
sdata->u.mesh.last_sn_update = jiffies;
}
lifetime = default_lifetime(sdata);
ttl = sdata->u.mesh.mshcfg.element_ttl;
if (ttl == 0) {
sdata->u.mesh.mshstats.dropped_frames_ttl++;
spin_unlock_bh(&mpath->state_lock);
goto enddiscovery;
}
if (preq_node->flags & PREQ_Q_F_REFRESH)
target_flags = MP_F_DO;
else
target_flags = MP_F_RF;
spin_unlock_bh(&mpath->state_lock);
mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr,
cpu_to_le32(ifmsh->sn), target_flags, mpath->dst,
cpu_to_le32(mpath->sn), broadcast_addr, 0,
ttl, cpu_to_le32(lifetime), 0,
cpu_to_le32(ifmsh->preq_id++), sdata);
mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);
enddiscovery:
rcu_read_unlock();
kfree(preq_node);
}
/**
* mesh_nexthop_lookup - put the appropriate next hop on a mesh frame
*
* @skb: 802.11 frame to be sent
* @sdata: network subif the frame will be sent through
*
* Returns: 0 if the next hop was found. Nonzero otherwise. If no next hop is
* found, the function will start a path discovery and queue the frame so it is
* sent when the path is resolved. This means the caller must not free the skb
* in this case.
*/
int mesh_nexthop_lookup(struct sk_buff *skb,
struct ieee80211_sub_if_data *sdata)
{
struct sk_buff *skb_to_free = NULL;
struct mesh_path *mpath;
struct sta_info *next_hop;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
u8 *target_addr = hdr->addr3;
int err = 0;
rcu_read_lock();
mpath = mesh_path_lookup(target_addr, sdata);
if (!mpath) {
mesh_path_add(target_addr, sdata);
mpath = mesh_path_lookup(target_addr, sdata);
if (!mpath) {
sdata->u.mesh.mshstats.dropped_frames_no_route++;
err = -ENOSPC;
goto endlookup;
}
}
if (mpath->flags & MESH_PATH_ACTIVE) {
if (time_after(jiffies,
mpath->exp_time -
msecs_to_jiffies(sdata->u.mesh.mshcfg.path_refresh_time)) &&
!memcmp(sdata->vif.addr, hdr->addr4, ETH_ALEN) &&
!(mpath->flags & MESH_PATH_RESOLVING) &&
!(mpath->flags & MESH_PATH_FIXED)) {
mesh_queue_preq(mpath,
PREQ_Q_F_START | PREQ_Q_F_REFRESH);
}
next_hop = rcu_dereference(mpath->next_hop);
if (next_hop) {
memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
} else
err = -ENOENT;
} else {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
if (!(mpath->flags & MESH_PATH_RESOLVING)) {
/* Start discovery only if it is not running yet */
mesh_queue_preq(mpath, PREQ_Q_F_START);
}
if (skb_queue_len(&mpath->frame_queue) >= MESH_FRAME_QUEUE_LEN)
skb_to_free = skb_dequeue(&mpath->frame_queue);
info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
ieee80211_set_qos_hdr(sdata, skb);
skb_queue_tail(&mpath->frame_queue, skb);
if (skb_to_free)
mesh_path_discard_frame(skb_to_free, sdata);
err = -ENOENT;
}
endlookup:
rcu_read_unlock();
return err;
}
void mesh_path_timer(unsigned long data)
{
struct mesh_path *mpath = (void *) data;
struct ieee80211_sub_if_data *sdata = mpath->sdata;
int ret;
if (sdata->local->quiescing)
return;
spin_lock_bh(&mpath->state_lock);
if (mpath->flags & MESH_PATH_RESOLVED ||
(!(mpath->flags & MESH_PATH_RESOLVING))) {
mpath->flags &= ~(MESH_PATH_RESOLVING | MESH_PATH_RESOLVED);
spin_unlock_bh(&mpath->state_lock);
} else if (mpath->discovery_retries < max_preq_retries(sdata)) {
++mpath->discovery_retries;
mpath->discovery_timeout *= 2;
mpath->flags &= ~MESH_PATH_REQ_QUEUED;
spin_unlock_bh(&mpath->state_lock);
mesh_queue_preq(mpath, 0);
} else {
mpath->flags = 0;
mpath->exp_time = jiffies;
spin_unlock_bh(&mpath->state_lock);
if (!mpath->is_gate && mesh_gate_num(sdata) > 0) {
ret = mesh_path_send_to_gates(mpath);
if (ret)
mhwmp_dbg("no gate was reachable");
} else
mesh_path_flush_pending(mpath);
}
}
void
mesh_path_tx_root_frame(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
u32 interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
u8 flags;
flags = (ifmsh->mshcfg.dot11MeshGateAnnouncementProtocol)
? RANN_FLAG_IS_GATE : 0;
mesh_path_sel_frame_tx(MPATH_RANN, flags, sdata->vif.addr,
cpu_to_le32(++ifmsh->sn),
0, NULL, 0, broadcast_addr,
0, sdata->u.mesh.mshcfg.element_ttl,
cpu_to_le32(interval), 0, 0, sdata);
}