Commit 73da7d5b authored by Simon Wunderlich's avatar Simon Wunderlich Committed by Johannes Berg

mac80211: add channel switch command and beacon callbacks

The count field in CSA must be decremented with each beacon
transmitted. This patch implements the functionality for drivers
using ieee80211_beacon_get(). Other drivers must call back manually
after reaching count == 0.

This patch also contains the handling and finish worker for the channel
switch command, and mac80211/chanctx code to allow to change a channel
definition of an active channel context.
Signed-off-by: default avatarSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: default avatarMathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
[small cleanups, catch identical chandef]
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 16ef1fe2
......@@ -152,11 +152,14 @@ struct ieee80211_low_level_stats {
* @IEEE80211_CHANCTX_CHANGE_WIDTH: The channel width changed
* @IEEE80211_CHANCTX_CHANGE_RX_CHAINS: The number of RX chains changed
* @IEEE80211_CHANCTX_CHANGE_RADAR: radar detection flag changed
* @IEEE80211_CHANCTX_CHANGE_CHANNEL: switched to another operating channel,
* this is used only with channel switching with CSA
*/
enum ieee80211_chanctx_change {
IEEE80211_CHANCTX_CHANGE_WIDTH = BIT(0),
IEEE80211_CHANCTX_CHANGE_RX_CHAINS = BIT(1),
IEEE80211_CHANCTX_CHANGE_RADAR = BIT(2),
IEEE80211_CHANCTX_CHANGE_CHANNEL = BIT(3),
};
/**
......@@ -1084,6 +1087,7 @@ enum ieee80211_vif_flags {
* @addr: address of this interface
* @p2p: indicates whether this AP or STA interface is a p2p
* interface, i.e. a GO or p2p-sta respectively
* @csa_active: marks whether a channel switch is going on
* @driver_flags: flags/capabilities the driver has for this interface,
* these need to be set (or cleared) when the interface is added
* or, if supported by the driver, the interface type is changed
......@@ -1106,6 +1110,7 @@ struct ieee80211_vif {
struct ieee80211_bss_conf bss_conf;
u8 addr[ETH_ALEN];
bool p2p;
bool csa_active;
u8 cab_queue;
u8 hw_queue[IEEE80211_NUM_ACS];
......@@ -2637,6 +2642,16 @@ enum ieee80211_roc_type {
* @ipv6_addr_change: IPv6 address assignment on the given interface changed.
* Currently, this is only called for managed or P2P client interfaces.
* This callback is optional; it must not sleep.
*
* @channel_switch_beacon: Starts a channel switch to a new channel.
* Beacons are modified to include CSA or ECSA IEs before calling this
* function. The corresponding count fields in these IEs must be
* decremented, and when they reach zero the driver must call
* ieee80211_csa_finish(). Drivers which use ieee80211_beacon_get()
* get the csa counter decremented by mac80211, but must check if it is
* zero using ieee80211_csa_is_complete() after the beacon has been
* transmitted and then call ieee80211_csa_finish().
*
*/
struct ieee80211_ops {
void (*tx)(struct ieee80211_hw *hw,
......@@ -2824,6 +2839,9 @@ struct ieee80211_ops {
struct ieee80211_vif *vif,
struct inet6_dev *idev);
#endif
void (*channel_switch_beacon)(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct cfg80211_chan_def *chandef);
};
/**
......@@ -3318,6 +3336,25 @@ static inline struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
return ieee80211_beacon_get_tim(hw, vif, NULL, NULL);
}
/**
* ieee80211_csa_finish - notify mac80211 about channel switch
* @vif: &struct ieee80211_vif pointer from the add_interface callback.
*
* After a channel switch announcement was scheduled and the counter in this
* announcement hit zero, this function must be called by the driver to
* notify mac80211 that the channel can be changed.
*/
void ieee80211_csa_finish(struct ieee80211_vif *vif);
/**
* ieee80211_csa_is_complete - find out if counters reached zero
* @vif: &struct ieee80211_vif pointer from the add_interface callback.
*
* This function returns whether the channel switch counters reached zero.
*/
bool ieee80211_csa_is_complete(struct ieee80211_vif *vif);
/**
* ieee80211_proberesp_get - retrieve a Probe Response template
* @hw: pointer obtained from ieee80211_alloc_hw().
......
......@@ -860,8 +860,8 @@ static int ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata,
return 0;
}
static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_beacon_data *params)
int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_beacon_data *params)
{
struct beacon_data *new, *old;
int new_head_len, new_tail_len;
......@@ -1024,6 +1024,12 @@ static int ieee80211_change_beacon(struct wiphy *wiphy, struct net_device *dev,
sdata = IEEE80211_DEV_TO_SUB_IF(dev);
/* don't allow changing the beacon while CSA is in place - offset
* of channel switch counter may change
*/
if (sdata->vif.csa_active)
return -EBUSY;
old = rtnl_dereference(sdata->u.ap.beacon);
if (!old)
return -ENOENT;
......@@ -1048,6 +1054,10 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
return -ENOENT;
old_probe_resp = rtnl_dereference(sdata->u.ap.probe_resp);
/* abort any running channel switch */
sdata->vif.csa_active = false;
cancel_work_sync(&sdata->csa_finalize_work);
/* turn off carrier for this interface and dependent VLANs */
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
netif_carrier_off(vlan->dev);
......@@ -2775,6 +2785,178 @@ static int ieee80211_start_radar_detection(struct wiphy *wiphy,
return 0;
}
static struct cfg80211_beacon_data *
cfg80211_beacon_dup(struct cfg80211_beacon_data *beacon)
{
struct cfg80211_beacon_data *new_beacon;
u8 *pos;
int len;
len = beacon->head_len + beacon->tail_len + beacon->beacon_ies_len +
beacon->proberesp_ies_len + beacon->assocresp_ies_len +
beacon->probe_resp_len;
new_beacon = kzalloc(sizeof(*new_beacon) + len, GFP_KERNEL);
if (!new_beacon)
return NULL;
pos = (u8 *)(new_beacon + 1);
if (beacon->head_len) {
new_beacon->head_len = beacon->head_len;
new_beacon->head = pos;
memcpy(pos, beacon->head, beacon->head_len);
pos += beacon->head_len;
}
if (beacon->tail_len) {
new_beacon->tail_len = beacon->tail_len;
new_beacon->tail = pos;
memcpy(pos, beacon->tail, beacon->tail_len);
pos += beacon->tail_len;
}
if (beacon->beacon_ies_len) {
new_beacon->beacon_ies_len = beacon->beacon_ies_len;
new_beacon->beacon_ies = pos;
memcpy(pos, beacon->beacon_ies, beacon->beacon_ies_len);
pos += beacon->beacon_ies_len;
}
if (beacon->proberesp_ies_len) {
new_beacon->proberesp_ies_len = beacon->proberesp_ies_len;
new_beacon->proberesp_ies = pos;
memcpy(pos, beacon->proberesp_ies, beacon->proberesp_ies_len);
pos += beacon->proberesp_ies_len;
}
if (beacon->assocresp_ies_len) {
new_beacon->assocresp_ies_len = beacon->assocresp_ies_len;
new_beacon->assocresp_ies = pos;
memcpy(pos, beacon->assocresp_ies, beacon->assocresp_ies_len);
pos += beacon->assocresp_ies_len;
}
if (beacon->probe_resp_len) {
new_beacon->probe_resp_len = beacon->probe_resp_len;
beacon->probe_resp = pos;
memcpy(pos, beacon->probe_resp, beacon->probe_resp_len);
pos += beacon->probe_resp_len;
}
return new_beacon;
}
void ieee80211_csa_finalize_work(struct work_struct *work)
{
struct ieee80211_sub_if_data *sdata =
container_of(work, struct ieee80211_sub_if_data,
csa_finalize_work);
struct ieee80211_local *local = sdata->local;
int err, changed;
if (!ieee80211_sdata_running(sdata))
return;
if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
return;
sdata->radar_required = sdata->csa_radar_required;
err = ieee80211_vif_change_channel(sdata, &local->csa_chandef,
&changed);
if (WARN_ON(err < 0))
return;
err = ieee80211_assign_beacon(sdata, sdata->u.ap.next_beacon);
if (err < 0)
return;
changed |= err;
kfree(sdata->u.ap.next_beacon);
sdata->u.ap.next_beacon = NULL;
sdata->vif.csa_active = false;
ieee80211_wake_queues_by_reason(&sdata->local->hw,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_CSA);
ieee80211_bss_info_change_notify(sdata, changed);
cfg80211_ch_switch_notify(sdata->dev, &local->csa_chandef);
}
static int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
struct cfg80211_csa_settings *params)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = sdata->local;
struct ieee80211_chanctx_conf *chanctx_conf;
struct ieee80211_chanctx *chanctx;
int err, num_chanctx;
if (!list_empty(&local->roc_list) || local->scanning)
return -EBUSY;
if (sdata->wdev.cac_started)
return -EBUSY;
if (cfg80211_chandef_identical(&params->chandef,
&sdata->vif.bss_conf.chandef))
return -EINVAL;
rcu_read_lock();
chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
if (!chanctx_conf) {
rcu_read_unlock();
return -EBUSY;
}
/* don't handle for multi-VIF cases */
chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf);
if (chanctx->refcount > 1) {
rcu_read_unlock();
return -EBUSY;
}
num_chanctx = 0;
list_for_each_entry_rcu(chanctx, &local->chanctx_list, list)
num_chanctx++;
rcu_read_unlock();
if (num_chanctx > 1)
return -EBUSY;
/* don't allow another channel switch if one is already active. */
if (sdata->vif.csa_active)
return -EBUSY;
/* only handle AP for now. */
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP:
break;
default:
return -EOPNOTSUPP;
}
sdata->u.ap.next_beacon = cfg80211_beacon_dup(&params->beacon_after);
if (!sdata->u.ap.next_beacon)
return -ENOMEM;
sdata->csa_counter_offset_beacon = params->counter_offset_beacon;
sdata->csa_counter_offset_presp = params->counter_offset_presp;
sdata->csa_radar_required = params->radar_required;
if (params->block_tx)
ieee80211_stop_queues_by_reason(&local->hw,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_CSA);
err = ieee80211_assign_beacon(sdata, &params->beacon_csa);
if (err < 0)
return err;
local->csa_chandef = params->chandef;
sdata->vif.csa_active = true;
ieee80211_bss_info_change_notify(sdata, err);
drv_channel_switch_beacon(sdata, &params->chandef);
return 0;
}
static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
struct ieee80211_channel *chan, bool offchan,
unsigned int wait, const u8 *buf, size_t len,
......@@ -3492,4 +3674,5 @@ struct cfg80211_ops mac80211_config_ops = {
.get_et_strings = ieee80211_get_et_strings,
.get_channel = ieee80211_cfg_get_channel,
.start_radar_detection = ieee80211_start_radar_detection,
.channel_switch = ieee80211_channel_switch,
};
......@@ -410,6 +410,64 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
return ret;
}
int ieee80211_vif_change_channel(struct ieee80211_sub_if_data *sdata,
const struct cfg80211_chan_def *chandef,
u32 *changed)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_chanctx_conf *conf;
struct ieee80211_chanctx *ctx;
int ret;
u32 chanctx_changed = 0;
/* should never be called if not performing a channel switch. */
if (WARN_ON(!sdata->vif.csa_active))
return -EINVAL;
if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
IEEE80211_CHAN_DISABLED))
return -EINVAL;
mutex_lock(&local->chanctx_mtx);
conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
lockdep_is_held(&local->chanctx_mtx));
if (!conf) {
ret = -EINVAL;
goto out;
}
ctx = container_of(conf, struct ieee80211_chanctx, conf);
if (ctx->refcount != 1) {
ret = -EINVAL;
goto out;
}
if (sdata->vif.bss_conf.chandef.width != chandef->width) {
chanctx_changed = IEEE80211_CHANCTX_CHANGE_WIDTH;
*changed |= BSS_CHANGED_BANDWIDTH;
}
sdata->vif.bss_conf.chandef = *chandef;
ctx->conf.def = *chandef;
chanctx_changed |= IEEE80211_CHANCTX_CHANGE_CHANNEL;
drv_change_chanctx(local, ctx, chanctx_changed);
if (!local->use_chanctx) {
local->_oper_chandef = *chandef;
ieee80211_hw_config(local, 0);
}
ieee80211_recalc_chanctx_chantype(local, ctx);
ieee80211_recalc_smps_chanctx(local, ctx);
ieee80211_recalc_radar_chanctx(local, ctx);
ret = 0;
out:
mutex_unlock(&local->chanctx_mtx);
return ret;
}
int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
const struct cfg80211_chan_def *chandef,
u32 *changed)
......
......@@ -1072,4 +1072,17 @@ static inline void drv_ipv6_addr_change(struct ieee80211_local *local,
}
#endif
static inline void
drv_channel_switch_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_chan_def *chandef)
{
struct ieee80211_local *local = sdata->local;
if (local->ops->channel_switch_beacon) {
trace_drv_channel_switch_beacon(local, sdata, chandef);
local->ops->channel_switch_beacon(&local->hw, &sdata->vif,
chandef);
}
}
#endif /* __MAC80211_DRIVER_OPS */
......@@ -259,6 +259,8 @@ struct ieee80211_if_ap {
struct beacon_data __rcu *beacon;
struct probe_resp __rcu *probe_resp;
/* to be used after channel switch. */
struct cfg80211_beacon_data *next_beacon;
struct list_head vlans;
struct ps_data ps;
......@@ -716,6 +718,11 @@ struct ieee80211_sub_if_data {
struct ieee80211_tx_queue_params tx_conf[IEEE80211_NUM_ACS];
struct work_struct csa_finalize_work;
int csa_counter_offset_beacon;
int csa_counter_offset_presp;
bool csa_radar_required;
/* used to reconfigure hardware SM PS */
struct work_struct recalc_smps;
......@@ -1372,6 +1379,9 @@ void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc, bool free);
void ieee80211_sw_roc_work(struct work_struct *work);
void ieee80211_handle_roc_started(struct ieee80211_roc_work *roc);
/* channel switch handling */
void ieee80211_csa_finalize_work(struct work_struct *work);
/* interface handling */
int ieee80211_iface_init(void);
void ieee80211_iface_exit(void);
......@@ -1393,6 +1403,8 @@ void ieee80211_del_virtual_monitor(struct ieee80211_local *local);
bool __ieee80211_recalc_txpower(struct ieee80211_sub_if_data *sdata);
void ieee80211_recalc_txpower(struct ieee80211_sub_if_data *sdata);
int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_beacon_data *params);
static inline bool ieee80211_sdata_running(struct ieee80211_sub_if_data *sdata)
{
......@@ -1654,6 +1666,11 @@ int __must_check
ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
const struct cfg80211_chan_def *chandef,
u32 *changed);
/* NOTE: only use ieee80211_vif_change_channel() for channel switch */
int __must_check
ieee80211_vif_change_channel(struct ieee80211_sub_if_data *sdata,
const struct cfg80211_chan_def *chandef,
u32 *changed);
void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata);
void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata);
void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
......
......@@ -274,6 +274,12 @@ static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
if (iftype == NL80211_IFTYPE_ADHOC &&
nsdata->vif.type == NL80211_IFTYPE_ADHOC)
return -EBUSY;
/*
* will not add another interface while any channel
* switch is active.
*/
if (nsdata->vif.csa_active)
return -EBUSY;
/*
* The remaining checks are only performed for interfaces
......@@ -804,6 +810,8 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
cancel_work_sync(&local->dynamic_ps_enable_work);
cancel_work_sync(&sdata->recalc_smps);
sdata->vif.csa_active = false;
cancel_work_sync(&sdata->csa_finalize_work);
cancel_delayed_work_sync(&sdata->dfs_cac_timer_work);
......@@ -1267,6 +1275,7 @@ static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
skb_queue_head_init(&sdata->skb_queue);
INIT_WORK(&sdata->work, ieee80211_iface_work);
INIT_WORK(&sdata->recalc_smps, ieee80211_recalc_smps_work);
INIT_WORK(&sdata->csa_finalize_work, ieee80211_csa_finalize_work);
switch (type) {
case NL80211_IFTYPE_P2P_GO:
......
......@@ -1906,6 +1906,32 @@ TRACE_EVENT(api_radar_detected,
)
);
TRACE_EVENT(drv_channel_switch_beacon,
TP_PROTO(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata,
struct cfg80211_chan_def *chandef),
TP_ARGS(local, sdata, chandef),
TP_STRUCT__entry(
LOCAL_ENTRY
VIF_ENTRY
CHANDEF_ENTRY
),
TP_fast_assign(
LOCAL_ASSIGN;
VIF_ASSIGN;
CHANDEF_ASSIGN(chandef);
),
TP_printk(
LOCAL_PR_FMT VIF_PR_FMT " channel switch to " CHANDEF_PR_FMT,
LOCAL_PR_ARG, VIF_PR_ARG, CHANDEF_PR_ARG
)
);
#ifdef CONFIG_MAC80211_MESSAGE_TRACING
#undef TRACE_SYSTEM
#define TRACE_SYSTEM mac80211_msg
......
......@@ -2338,6 +2338,81 @@ static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
return 0;
}
void ieee80211_csa_finish(struct ieee80211_vif *vif)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
ieee80211_queue_work(&sdata->local->hw,
&sdata->csa_finalize_work);
}
EXPORT_SYMBOL(ieee80211_csa_finish);
static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
struct beacon_data *beacon)
{
struct probe_resp *resp;
int counter_offset_beacon = sdata->csa_counter_offset_beacon;
int counter_offset_presp = sdata->csa_counter_offset_presp;
/* warn if the driver did not check for/react to csa completeness */
if (WARN_ON(((u8 *)beacon->tail)[counter_offset_beacon] == 0))
return;
((u8 *)beacon->tail)[counter_offset_beacon]--;
if (sdata->vif.type == NL80211_IFTYPE_AP &&
counter_offset_presp) {
rcu_read_lock();
resp = rcu_dereference(sdata->u.ap.probe_resp);
/* if nl80211 accepted the offset, this should not happen. */
if (WARN_ON(!resp)) {
rcu_read_unlock();
return;
}
resp->data[counter_offset_presp]--;
rcu_read_unlock();
}
}
bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct beacon_data *beacon = NULL;
u8 *beacon_data;
size_t beacon_data_len;
int counter_beacon = sdata->csa_counter_offset_beacon;
int ret = false;
if (!ieee80211_sdata_running(sdata))
return false;
rcu_read_lock();
if (vif->type == NL80211_IFTYPE_AP) {
struct ieee80211_if_ap *ap = &sdata->u.ap;
beacon = rcu_dereference(ap->beacon);
if (WARN_ON(!beacon || !beacon->tail))
goto out;
beacon_data = beacon->tail;
beacon_data_len = beacon->tail_len;
} else {
WARN_ON(1);
goto out;
}
if (WARN_ON(counter_beacon > beacon_data_len))
goto out;
if (beacon_data[counter_beacon] == 0)
ret = true;
out:
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL(ieee80211_csa_is_complete);
struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
u16 *tim_offset, u16 *tim_length)
......@@ -2368,6 +2443,9 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
struct beacon_data *beacon = rcu_dereference(ap->beacon);
if (beacon) {
if (sdata->vif.csa_active)
ieee80211_update_csa(sdata, beacon);
/*
* headroom, head length,
* tail length and maximum TIM length
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment