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
The drivers like to support the channel switch offloading function will have
to provide the mactime information (at least for mgmt and action frames)
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@xxxxxxxxx>
---
v2: use "mactime" instead of timestamp in the frame body, the driver has to provide the mactime if need to support the channel switch function
---
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 | 48 ++++++++++++++++++++++++++++++++++++++---
5 files changed, 138 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..19b53a8 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 {
@@ -1315,7 +1353,8 @@ 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);
+ ieee80211_sta_process_chanswitch(sdata, sw_elem,
+ bss, rx_status->mactime);
}
}
@@ -1647,7 +1686,8 @@ 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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