From: Wey-Yi Guy <wey-yi.w.guy@xxxxxxxxx>
Adding support to offload the channel switch operation to driver if
driver can support the function.
The original approach, mac80211 utilize the mac_config callback function
and set the CHANNEL_CHANGE flag which is difficult to separate the true
channel switch request from all the other channel changes condition;
with this offload approach, driver has more control on how to handle the
channel switch request from AP, also can provide more accurate timing
calculation
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@xxxxxxxxx>
---
include/net/mac80211.h | 32 ++++++++++++++++++++++++++
net/mac80211/driver-ops.h | 11 +++++++++
net/mac80211/driver-trace.h | 49 +++++++++++++++++++++++++++++++++++++++
net/mac80211/ieee80211_i.h | 3 +-
net/mac80211/mlme.c | 53 +++++++++++++++++++++++++++++++++++++++---
5 files changed, 143 insertions(+), 5 deletions(-)
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 2879c8e..dc5ae23 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -708,6 +708,26 @@ struct ieee80211_conf {
};
/**
+ * struct ieee80211_channel_switch - holds the channel switch data
+ *
+ * The information provided in this structure is required for channel switch
+ * operation.
+ *
+ * @timestamp: value in microseconds of the 64-bit Time Synchronization
+ * Function (TSF) timer when the channel switch ie received.
+ * @block_tx: set to true if no more future frames transmission within the BSS
+ * until the scheduled channel switch
+ * @channel: pointer to ieee80211_channel contain then new channel information
+ * @count: specified the number of TBTT's until the channel switch event.
+ */
+struct ieee80211_channel_switch {
+ u64 timestamp;
+ bool block_tx;
+ struct ieee80211_channel *channel;
+ u8 count;
+};
+
+/**
* struct ieee80211_vif - per-interface data
*
* Data in this structure is continually present for driver
@@ -1694,6 +1714,8 @@ struct ieee80211_ops {
int (*testmode_cmd)(struct ieee80211_hw *hw, void *data, int len);
#endif
void (*flush)(struct ieee80211_hw *hw, bool drop);
+ void (*channel_switch)(struct ieee80211_hw *hw,
+ struct ieee80211_channel_switch *ch_switch);
};
/**
@@ -2444,6 +2466,16 @@ void ieee80211_cqm_rssi_notify(struct ieee80211_vif *vif,
enum nl80211_cqm_rssi_threshold_event rssi_event,
gfp_t gfp);
+/**
+ * ieee80211_chswitch_done - Complete channel switch process
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
+ * @is_seccess: make the channel switch successful or not
+ *
+ * Complete the channel switch post-process: set the new operational channel
+ * and wake up the suspended queues.
+ */
+void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool is_success);
+
/* Rate control API */
/**
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 997008e..5662bb5 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -373,4 +373,15 @@ static inline void drv_flush(struct ieee80211_local *local, bool drop)
if (local->ops->flush)
local->ops->flush(&local->hw, drop);
}
+
+static inline void drv_channel_switch(struct ieee80211_local *local,
+ struct ieee80211_channel_switch *ch_switch)
+{
+ might_sleep();
+
+ local->ops->channel_switch(&local->hw, ch_switch);
+
+ trace_drv_channel_switch(local, ch_switch);
+}
+
#endif /* __MAC80211_DRIVER_OPS */
diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index ce734b5..cd1ae9f 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -774,6 +774,34 @@ TRACE_EVENT(drv_flush,
)
);
+TRACE_EVENT(drv_channel_switch,
+ TP_PROTO(struct ieee80211_local *local,
+ struct ieee80211_channel_switch *ch_switch),
+
+ TP_ARGS(local, ch_switch),
+
+ TP_STRUCT__entry(
+ LOCAL_ENTRY
+ __field(u64, timestamp)
+ __field(bool, block_tx)
+ __field(u16, freq)
+ __field(u8, count)
+ ),
+
+ TP_fast_assign(
+ LOCAL_ASSIGN;
+ __entry->timestamp = ch_switch->timestamp;
+ __entry->block_tx = ch_switch->block_tx;
+ __entry->freq = ch_switch->channel->center_freq;
+ __entry->count = ch_switch->count;
+ ),
+
+ TP_printk(
+ LOCAL_PR_FMT " new freq:%u count:%d",
+ LOCAL_PR_ARG, __entry->freq, __entry->count
+ )
+);
+
/*
* Tracing for API calls that drivers call.
*/
@@ -992,6 +1020,27 @@ TRACE_EVENT(api_sta_block_awake,
)
);
+TRACE_EVENT(api_chswitch_done,
+ TP_PROTO(struct ieee80211_sub_if_data *sdata, bool is_success),
+
+ TP_ARGS(sdata, is_success),
+
+ TP_STRUCT__entry(
+ VIF_ENTRY
+ __field(bool, is_success)
+ ),
+
+ TP_fast_assign(
+ VIF_ASSIGN;
+ __entry->is_success = is_success;
+ ),
+
+ TP_printk(
+ VIF_PR_FMT " chswitch:%d",
+ VIF_PR_ARG, __entry->is_success
+ )
+);
+
/*
* Tracing for internal functions
* (which may also be called in response to driver calls)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 4e73660..be9dda9 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -999,7 +999,8 @@ int ieee80211_max_network_latency(struct notifier_block *nb,
unsigned long data, void *dummy);
void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
struct ieee80211_channel_sw_ie *sw_elem,
- struct ieee80211_bss *bss);
+ struct ieee80211_bss *bss,
+ u64 timestamp);
void ieee80211_sta_quiesce(struct ieee80211_sub_if_data *sdata);
void ieee80211_sta_restart(struct ieee80211_sub_if_data *sdata);
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 358226f..f50d73f 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -340,7 +340,11 @@ static void ieee80211_chswitch_work(struct work_struct *work)
goto out;
sdata->local->oper_channel = sdata->local->csa_channel;
- ieee80211_hw_config(sdata->local, IEEE80211_CONF_CHANGE_CHANNEL);
+ if (!sdata->local->ops->channel_switch) {
+ /* call "hw_config" only if doing sw channel switch */
+ ieee80211_hw_config(sdata->local,
+ IEEE80211_CONF_CHANGE_CHANNEL);
+ }
/* XXX: shouldn't really modify cfg80211-owned data! */
ifmgd->associated->channel = sdata->local->oper_channel;
@@ -352,6 +356,22 @@ static void ieee80211_chswitch_work(struct work_struct *work)
mutex_unlock(&ifmgd->mtx);
}
+void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool is_success)
+{
+ struct ieee80211_sub_if_data *sdata;
+ struct ieee80211_if_managed *ifmgd;
+
+ sdata = vif_to_sdata(vif);
+ ifmgd = &sdata->u.mgd;
+
+ trace_api_chswitch_done(sdata, is_success);
+ if (!is_success)
+ sdata->local->csa_channel = sdata->local->oper_channel;
+
+ ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
+}
+EXPORT_SYMBOL(ieee80211_chswitch_done);
+
static void ieee80211_chswitch_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata =
@@ -368,7 +388,8 @@ static void ieee80211_chswitch_timer(unsigned long data)
void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
struct ieee80211_channel_sw_ie *sw_elem,
- struct ieee80211_bss *bss)
+ struct ieee80211_bss *bss,
+ u64 timestamp)
{
struct cfg80211_bss *cbss =
container_of((void *)bss, struct cfg80211_bss, priv);
@@ -396,6 +417,23 @@ void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
sdata->local->csa_channel = new_ch;
+ if (sdata->local->ops->channel_switch) {
+ /* use driver's channel switch callback */
+ struct ieee80211_channel_switch ch_switch;
+ memset(&ch_switch, 0, sizeof(ch_switch));
+ ch_switch.timestamp = timestamp;
+ if (sw_elem->mode) {
+ ch_switch.block_tx = true;
+ ieee80211_stop_queues_by_reason(&sdata->local->hw,
+ IEEE80211_QUEUE_STOP_REASON_CSA);
+ }
+ ch_switch.channel = new_ch;
+ ch_switch.count = sw_elem->count;
+ ifmgd->flags |= IEEE80211_STA_CSA_RECEIVED;
+ drv_channel_switch(sdata->local, &ch_switch);
+ return;
+ }
+ /* mac80211 handle channel switch */
if (sw_elem->count <= 1) {
ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
} else {
@@ -1279,6 +1317,7 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
struct ieee80211_bss *bss;
struct ieee80211_channel *channel;
bool need_ps = false;
+ u64 timestamp;
if (sdata->u.mgd.associated) {
bss = (void *)sdata->u.mgd.associated->priv;
@@ -1315,7 +1354,12 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
ETH_ALEN) == 0)) {
struct ieee80211_channel_sw_ie *sw_elem =
(struct ieee80211_channel_sw_ie *)elems->ch_switch_elem;
- ieee80211_sta_process_chanswitch(sdata, sw_elem, bss);
+ if (beacon)
+ timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
+ else
+ timestamp = le64_to_cpu(mgmt->u.probe_resp.timestamp);
+ ieee80211_sta_process_chanswitch(sdata, sw_elem,
+ bss, timestamp);
}
}
@@ -1647,7 +1691,8 @@ static void ieee80211_sta_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
ieee80211_sta_process_chanswitch(sdata,
&mgmt->u.action.u.chan_switch.sw_elem,
- (void *)ifmgd->associated->priv);
+ (void *)ifmgd->associated->priv,
+ rx_status->mactime);
break;
}
mutex_unlock(&ifmgd->mtx);
--
1.5.6.3
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