[PATCH 0/8] mac80211/cfg80211/iwlwifi: a few channel-switch patches

[PATCH 0/8] mac80211/cfg80211/iwlwifi: a few channel-switch patches

[Luca Coelho]

From: Luciano Coelho <luciano.coelho@intel.com>

Hi,

These are a few channel-switch patches by Andrei that we have in our
internal tree.  I have rebased them for upstream.

--
Cheers,
Luca.

Andrei Otcheretianski (8):
  cfg80211: Add API to update CSA counters in mgmt frames
  mac80211: Update CSA counters in mgmt frames
  cfg80211: Support multiple CSA counters
  mac80211: Support multiple CSA counters
  iwlwifi: mvm: Add AP/GO channel switch support
  mac80211: Provide ieee80211_beacon_get_template API
  mac80211: Handle the CSA counters correctly
  iwlwifi: mvm: Use beacon_get_template instead of beacon_get

 drivers/net/wireless/iwlwifi/iwl-fw.h       |   2 +
 drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c |  15 ++-
 drivers/net/wireless/iwlwifi/mvm/mac80211.c |  44 ++++++-
 drivers/net/wireless/iwlwifi/mvm/mvm.h      |   2 +
 drivers/net/wireless/iwlwifi/mvm/ops.c      |   2 +-
 include/net/cfg80211.h                      |  22 +++-
 include/net/mac80211.h                      |  64 ++++++++--
 include/uapi/linux/nl80211.h                |  19 ++-
 net/mac80211/cfg.c                          |  38 +++++-
 net/mac80211/ibss.c                         |   2 +-
 net/mac80211/ieee80211_i.h                  |   5 +-
 net/mac80211/main.c                         |   2 +
 net/mac80211/mesh.c                         |   2 +-
 net/mac80211/tx.c                           | 189 ++++++++++++++++++++--------
 net/wireless/core.c                         |   2 +
 net/wireless/nl80211.c                      |  87 ++++++++++---
 net/wireless/trace.h                        |  22 ++--
 17 files changed, 418 insertions(+), 101 deletions(-)

-- 
2.0.0.rc0

[PATCH 1/8] cfg80211: Add API to update CSA counters in mgmt frames

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Add NL80211_ATTR_CSA_C_OFFSETS_TX which holds an array
of offsets to the CSA counters which should be updated
when sending a management frames with NL80211_CMD_FRAME.

This API should be used by the drivers that wish to keep the
CSA counter updated in probe responses, but do not implement
probe response offloading and so, do not use
ieee80211_proberesp_get function.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 include/net/cfg80211.h       |  4 ++++
 include/uapi/linux/nl80211.h |  8 ++++++++
 net/wireless/nl80211.c       | 24 ++++++++++++++++++++++--
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 5c7169b..ca1faf5 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1986,6 +1986,8 @@ struct cfg80211_update_ft_ies_params {
  * @len: buffer length
  * @no_cck: don't use cck rates for this frame
  * @dont_wait_for_ack: tells the low level not to wait for an ack
+ * @n_csa_offsets: length of csa_offsets array
+ * @csa_offsets: array of all the csa offsets in the frame
  */
 struct cfg80211_mgmt_tx_params {
 	struct ieee80211_channel *chan;
@@ -1995,6 +1997,8 @@ struct cfg80211_mgmt_tx_params {
 	size_t len;
 	bool no_cck;
 	bool dont_wait_for_ack;
+	int n_csa_offsets;
+	const u16 *csa_offsets;
 };
 
 /**
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 406010d..aaa752f 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -503,6 +503,9 @@
  *	TX status event pertaining to the TX request.
  *	%NL80211_ATTR_TX_NO_CCK_RATE is used to decide whether to send the
  *	management frames at CCK rate or not in 2GHz band.
+ *	%NL80211_ATTR_CSA_C_OFFSETS_TX is an array of offsets to CSA
+ *	counters which will be updated to the current value. This attribute
+ *	is used during CSA period.
  * @NL80211_CMD_FRAME_WAIT_CANCEL: When an off-channel TX was requested, this
  *	command may be used with the corresponding cookie to cancel the wait
  *	time if it is known that it is no longer necessary.
@@ -1576,6 +1579,9 @@ enum nl80211_commands {
  *	advertise values that cannot always be met. In such cases, an attempt
  *	to add a new station entry with @NL80211_CMD_NEW_STATION may fail.
  *
+ * @NL80211_ATTR_CSA_C_OFFSETS_TX: An array of csa counter offsets (u16) which
+ *	should be updated when the frame is transmitted.
+ *
  * @NL80211_ATTR_TDLS_PEER_CAPABILITY: flags for TDLS peer capabilities, u32.
  *	As specified in the &enum nl80211_tdls_peer_capability.
  *
@@ -1920,6 +1926,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_IFACE_SOCKET_OWNER,
 
+	NL80211_ATTR_CSA_C_OFFSETS_TX,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 0f1b18f2..f425a04 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -386,6 +386,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
 	[NL80211_ATTR_WIPHY_FREQ_HINT] = { .type = NLA_U32 },
 	[NL80211_ATTR_TDLS_PEER_CAPABILITY] = { .type = NLA_U32 },
 	[NL80211_ATTR_IFACE_SOCKET_OWNER] = { .type = NLA_FLAG },
+	[NL80211_ATTR_CSA_C_OFFSETS_TX] = { .type = NLA_BINARY },
 };
 
 /* policy for the key attributes */
@@ -7784,6 +7785,27 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info)
 	if (!chandef.chan && params.offchan)
 		return -EINVAL;
 
+	params.buf = nla_data(info->attrs[NL80211_ATTR_FRAME]);
+	params.len = nla_len(info->attrs[NL80211_ATTR_FRAME]);
+
+	if (info->attrs[NL80211_ATTR_CSA_C_OFFSETS_TX]) {
+		int len = nla_len(info->attrs[NL80211_ATTR_CSA_C_OFFSETS_TX]);
+		int i;
+
+		if (len % sizeof(u16))
+			return -EINVAL;
+
+		params.n_csa_offsets = len / sizeof(u16);
+		params.csa_offsets =
+			nla_data(info->attrs[NL80211_ATTR_CSA_C_OFFSETS_TX]);
+
+		/* check that all the offsets fit the frame */
+		for (i = 0; i < params.n_csa_offsets; i++) {
+			if (params.csa_offsets[i] >= params.len)
+				return -EINVAL;
+		}
+	}
+
 	if (!params.dont_wait_for_ack) {
 		msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 		if (!msg)
@@ -7797,8 +7819,6 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info)
 		}
 	}
 
-	params.buf = nla_data(info->attrs[NL80211_ATTR_FRAME]);
-	params.len = nla_len(info->attrs[NL80211_ATTR_FRAME]);
 	params.chan = chandef.chan;
 	err = cfg80211_mlme_mgmt_tx(rdev, wdev, &params, &cookie);
 	if (err)
-- 
2.0.0.rc0

[PATCH 2/8] mac80211: Update CSA counters in mgmt frames

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Track current csa counter value and use it
to update mgmt frames at the provided offsets.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 net/mac80211/cfg.c         | 16 +++++++++++++++-
 net/mac80211/ieee80211_i.h |  1 +
 net/mac80211/tx.c          |  5 +++--
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 7c56445..86c20a8 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3338,6 +3338,7 @@ __ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
 	sdata->csa_radar_required = params->radar_required;
 	sdata->csa_chandef = params->chandef;
 	sdata->csa_block_tx = params->block_tx;
+	sdata->csa_current_counter = params->count;
 	sdata->vif.csa_active = true;
 
 	if (sdata->csa_block_tx)
@@ -3382,6 +3383,7 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
 	bool need_offchan = false;
 	u32 flags;
 	int ret;
+	u8 *data;
 
 	if (params->dont_wait_for_ack)
 		flags = IEEE80211_TX_CTL_NO_ACK;
@@ -3475,8 +3477,20 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
 	}
 	skb_reserve(skb, local->hw.extra_tx_headroom);
 
-	memcpy(skb_put(skb, params->len), params->buf, params->len);
+	data = skb_put(skb, params->len);
+	memcpy(data, params->buf, params->len);
 
+	/* Update CSA counters*/
+	if (sdata->vif.csa_active &&
+	    (sdata->vif.type == NL80211_IFTYPE_AP ||
+	     sdata->vif.type == NL80211_IFTYPE_ADHOC) &&
+	    params->n_csa_offsets) {
+		int i;
+
+		for (i = 0; i < params->n_csa_offsets; i++)
+			data[params->csa_offsets[i]] =
+					sdata->csa_current_counter;
+	}
 	IEEE80211_SKB_CB(skb)->flags = flags;
 
 	skb->dev = sdata->dev;
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 4668ce9..fb2d9e7 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -766,6 +766,7 @@ struct ieee80211_sub_if_data {
 	struct ieee80211_chanctx *reserved_chanctx;
 	struct cfg80211_chan_def reserved_chandef;
 	bool reserved_radar_required;
+	u8 csa_current_counter;
 
 	/* used to reconfigure hardware SM PS */
 	struct work_struct recalc_smps;
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 19d36d4..263dea5 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2449,7 +2449,8 @@ static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
 	if (WARN_ON(beacon_data[counter_offset_beacon] == 1))
 		return;
 
-	beacon_data[counter_offset_beacon]--;
+	sdata->csa_current_counter--;
+	beacon_data[counter_offset_beacon] = sdata->csa_current_counter;
 
 	if (sdata->vif.type == NL80211_IFTYPE_AP && counter_offset_presp) {
 		rcu_read_lock();
@@ -2460,7 +2461,7 @@ static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
 			rcu_read_unlock();
 			return;
 		}
-		resp->data[counter_offset_presp]--;
+		resp->data[counter_offset_presp] = sdata->csa_current_counter;
 		rcu_read_unlock();
 	}
 }
-- 
2.0.0.rc0

[PATCH 3/8] cfg80211: Support multiple CSA counters

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Change the type of NL80211_ATTR_CSA_C_OFF_BEACON and
NL80211_ATTR_CSA_C_OFF_PRESP to be NLA_BINARY which allows
userspace to use beacons and probe responses with
multiple CSA counters.
This isn't breaking the API since userspace can
continue to use nla_put_u16 for this attributes, which
is equivalent to a single element u16 array.
In addition advertise max number of supported CSA counters.
This is needed when using CSA and eCSA IEs together.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 include/net/cfg80211.h       | 18 ++++++++++---
 include/uapi/linux/nl80211.h | 11 +++++---
 net/mac80211/cfg.c           | 10 +++++--
 net/wireless/core.c          |  2 ++
 net/wireless/nl80211.c       | 63 ++++++++++++++++++++++++++++++++++----------
 net/wireless/trace.h         | 22 +++++++++-------
 6 files changed, 94 insertions(+), 32 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index ca1faf5..8ac2cc6 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -694,8 +694,10 @@ struct cfg80211_ap_settings {
  *
  * @chandef: defines the channel to use after the switch
  * @beacon_csa: beacon data while performing the switch
- * @counter_offset_beacon: offset for the counter within the beacon (tail)
- * @counter_offset_presp: offset for the counter within the probe response
+ * @counter_offsets_beacon: offsets of the counters within the beacon (tail)
+ * @counter_offsets_presp: offsets of the counters within the probe response
+ * @n_counter_offsets_beacon: number of csa counters the beacon (tail)
+ * @n_counter_offsets_presp: number of csa counters in the probe response
  * @beacon_after: beacon data to be used on the new channel
  * @radar_required: whether radar detection is required on the new channel
  * @block_tx: whether transmissions should be blocked while changing
@@ -704,7 +706,10 @@ struct cfg80211_ap_settings {
 struct cfg80211_csa_settings {
 	struct cfg80211_chan_def chandef;
 	struct cfg80211_beacon_data beacon_csa;
-	u16 counter_offset_beacon, counter_offset_presp;
+	const u16 *counter_offsets_beacon;
+	const u16 *counter_offsets_presp;
+	unsigned int n_counter_offsets_beacon;
+	unsigned int n_counter_offsets_presp;
 	struct cfg80211_beacon_data beacon_after;
 	bool radar_required;
 	bool block_tx;
@@ -3046,6 +3051,13 @@ struct wiphy {
 
 	u16 max_ap_assoc_sta;
 
+	/*
+	 * Number of supported csa_counters in beacons and probe responses.
+	 * This value should be set if the driver wishes to limit the number of
+	 * csa counters. Default (0) means infinite.
+	 */
+	u8 max_num_csa_counters;
+
 	char priv[0] __aligned(NETDEV_ALIGN);
 };
 
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index aaa752f..a531bf3 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1528,10 +1528,10 @@ enum nl80211_commands {
  *	operation).
  * @NL80211_ATTR_CSA_IES: Nested set of attributes containing the IE information
  *	for the time while performing a channel switch.
- * @NL80211_ATTR_CSA_C_OFF_BEACON: Offset of the channel switch counter
- *	field in the beacons tail (%NL80211_ATTR_BEACON_TAIL).
- * @NL80211_ATTR_CSA_C_OFF_PRESP: Offset of the channel switch counter
- *	field in the probe response (%NL80211_ATTR_PROBE_RESP).
+ * @NL80211_ATTR_CSA_C_OFF_BEACON: An array of offsets (u16) to the channel
+ *	switch counters in the beacons tail (%NL80211_ATTR_BEACON_TAIL).
+ * @NL80211_ATTR_CSA_C_OFF_PRESP: An array of offsets (u16) to the channel
+ *	switch counters in the probe response (%NL80211_ATTR_PROBE_RESP).
  *
  * @NL80211_ATTR_RXMGMT_FLAGS: flags for nl80211_send_mgmt(), u32.
  *	As specified in the &enum nl80211_rxmgmt_flags.
@@ -1581,6 +1581,8 @@ enum nl80211_commands {
  *
  * @NL80211_ATTR_CSA_C_OFFSETS_TX: An array of csa counter offsets (u16) which
  *	should be updated when the frame is transmitted.
+ * @NL80211_ATTR_MAX_CSA_COUNTERS: U8 attribute used to advertise the maximum
+ *	supported number of csa counters.
  *
  * @NL80211_ATTR_TDLS_PEER_CAPABILITY: flags for TDLS peer capabilities, u32.
  *	As specified in the &enum nl80211_tdls_peer_capability.
@@ -1927,6 +1929,7 @@ enum nl80211_attrs {
 	NL80211_ATTR_IFACE_SOCKET_OWNER,
 
 	NL80211_ATTR_CSA_C_OFFSETS_TX,
+	NL80211_ATTR_MAX_CSA_COUNTERS,
 
 	/* add attributes here, update the policy in nl80211.c */
 
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 86c20a8..6f132a5 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3192,8 +3192,14 @@ static int ieee80211_set_csa_beacon(struct ieee80211_sub_if_data *sdata,
 			break;
 
 		sdata->csa_counter_offset_beacon =
-			params->counter_offset_beacon;
-		sdata->csa_counter_offset_presp = params->counter_offset_presp;
+			params->counter_offsets_beacon[0];
+
+		if (params->n_counter_offsets_presp)
+			sdata->csa_counter_offset_presp =
+				params->counter_offsets_presp[0];
+		else
+			sdata->csa_counter_offset_presp = 0;
+
 		err = ieee80211_assign_beacon(sdata, &params->beacon_csa);
 		if (err < 0) {
 			kfree(sdata->u.ap.next_beacon);
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 3978871..d03d8bd 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -402,6 +402,8 @@ struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
 	rdev->wiphy.rts_threshold = (u32) -1;
 	rdev->wiphy.coverage_class = 0;
 
+	rdev->wiphy.max_num_csa_counters = 1;
+
 	return &rdev->wiphy;
 }
 EXPORT_SYMBOL(wiphy_new);
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index f425a04..6cfff9b 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -371,8 +371,8 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
 	[NL80211_ATTR_CH_SWITCH_COUNT] = { .type = NLA_U32 },
 	[NL80211_ATTR_CH_SWITCH_BLOCK_TX] = { .type = NLA_FLAG },
 	[NL80211_ATTR_CSA_IES] = { .type = NLA_NESTED },
-	[NL80211_ATTR_CSA_C_OFF_BEACON] = { .type = NLA_U16 },
-	[NL80211_ATTR_CSA_C_OFF_PRESP] = { .type = NLA_U16 },
+	[NL80211_ATTR_CSA_C_OFF_BEACON] = { .type = NLA_BINARY },
+	[NL80211_ATTR_CSA_C_OFF_PRESP] = { .type = NLA_BINARY },
 	[NL80211_ATTR_STA_SUPPORTED_CHANNELS] = { .type = NLA_BINARY },
 	[NL80211_ATTR_STA_SUPPORTED_OPER_CLASSES] = { .type = NLA_BINARY },
 	[NL80211_ATTR_HANDLE_DFS] = { .type = NLA_FLAG },
@@ -1669,6 +1669,11 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
 			nla_nest_end(msg, nested);
 		}
 
+		if (dev->wiphy.flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH &&
+		    nla_put_u8(msg, NL80211_ATTR_MAX_CSA_COUNTERS,
+			       dev->wiphy.max_num_csa_counters))
+			goto nla_put_failure;
+
 		/* done */
 		state->split_start = 0;
 		break;
@@ -5862,6 +5867,7 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 	u8 radar_detect_width = 0;
 	int err;
 	bool need_new_beacon = false;
+	int len, i;
 
 	if (!rdev->ops->channel_switch ||
 	    !(rdev->wiphy.flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
@@ -5920,26 +5926,55 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 	if (!csa_attrs[NL80211_ATTR_CSA_C_OFF_BEACON])
 		return -EINVAL;
 
-	params.counter_offset_beacon =
-		nla_get_u16(csa_attrs[NL80211_ATTR_CSA_C_OFF_BEACON]);
-	if (params.counter_offset_beacon >= params.beacon_csa.tail_len)
+	len = nla_len(csa_attrs[NL80211_ATTR_CSA_C_OFF_BEACON]);
+	if (!len || (len % sizeof(u16)))
 		return -EINVAL;
 
-	/* sanity check - counters should be the same */
-	if (params.beacon_csa.tail[params.counter_offset_beacon] !=
-	    params.count)
+	params.n_counter_offsets_beacon = len / sizeof(u16);
+	if (rdev->wiphy.max_num_csa_counters &&
+	    (params.n_counter_offsets_beacon >
+	     rdev->wiphy.max_num_csa_counters))
 		return -EINVAL;
 
+	params.counter_offsets_beacon =
+		nla_data(csa_attrs[NL80211_ATTR_CSA_C_OFF_BEACON]);
+
+	/* sanity checks -counters should fit and be the same */
+	for (i = 0; i < params.n_counter_offsets_beacon; i++) {
+		u16 offset = params.counter_offsets_beacon[i];
+
+		if (offset >= params.beacon_csa.tail_len)
+			return -EINVAL;
+
+		if (params.beacon_csa.tail[offset] != params.count)
+			return -EINVAL;
+	}
+
 	if (csa_attrs[NL80211_ATTR_CSA_C_OFF_PRESP]) {
-		params.counter_offset_presp =
-			nla_get_u16(csa_attrs[NL80211_ATTR_CSA_C_OFF_PRESP]);
-		if (params.counter_offset_presp >=
-		    params.beacon_csa.probe_resp_len)
+		len = nla_len(csa_attrs[NL80211_ATTR_CSA_C_OFF_PRESP]);
+		if (!len || (len % sizeof(u16)))
 			return -EINVAL;
 
-		if (params.beacon_csa.probe_resp[params.counter_offset_presp] !=
-		    params.count)
+		params.n_counter_offsets_presp = len / sizeof(u16);
+		if (rdev->wiphy.max_num_csa_counters &&
+		    (params.n_counter_offsets_beacon >
+		     rdev->wiphy.max_num_csa_counters))
 			return -EINVAL;
+
+		params.counter_offsets_presp =
+			nla_data(csa_attrs[NL80211_ATTR_CSA_C_OFF_PRESP]);
+
+		/* sanity checks -counters should fit and be the same */
+		for (i = 0; i < params.n_counter_offsets_presp; i++) {
+			u16 offset = params.counter_offsets_presp[i];
+
+			if (offset >= params.beacon_csa.probe_resp_len)
+				return -EINVAL;
+
+			if (params.beacon_csa.probe_resp[offset] !=
+			    params.count)
+				return -EINVAL;
+		}
 	}
 
 skip_beacons:
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index cdfbb00..560ed77 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -1876,29 +1876,33 @@ TRACE_EVENT(rdev_channel_switch,
 		WIPHY_ENTRY
 		NETDEV_ENTRY
 		CHAN_DEF_ENTRY
-		__field(u16, counter_offset_beacon)
-		__field(u16, counter_offset_presp)
 		__field(bool, radar_required)
 		__field(bool, block_tx)
 		__field(u8, count)
+		__dynamic_array(u16, bcn_ofs, params->n_counter_offsets_beacon)
+		__dynamic_array(u16, pres_ofs, params->n_counter_offsets_presp)
 	),
 	TP_fast_assign(
 		WIPHY_ASSIGN;
 		NETDEV_ASSIGN;
 		CHAN_DEF_ASSIGN(&params->chandef);
-		__entry->counter_offset_beacon = params->counter_offset_beacon;
-		__entry->counter_offset_presp = params->counter_offset_presp;
 		__entry->radar_required = params->radar_required;
 		__entry->block_tx = params->block_tx;
 		__entry->count = params->count;
+		memcpy(__get_dynamic_array(bcn_ofs),
+		       params->counter_offsets_beacon,
+		       params->n_counter_offsets_beacon * sizeof(u16));
+
+		/* probe response offsets are optional */
+		if (params->n_counter_offsets_presp)
+			memcpy(__get_dynamic_array(pres_ofs),
+			       params->counter_offsets_presp,
+			       params->n_counter_offsets_presp * sizeof(u16));
 	),
 	TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", " CHAN_DEF_PR_FMT
-		  ", block_tx: %d, count: %u, radar_required: %d"
-		  ", counter offsets (beacon/presp): %u/%u",
+		  ", block_tx: %d, count: %u, radar_required: %d",
 		  WIPHY_PR_ARG, NETDEV_PR_ARG, CHAN_DEF_PR_ARG,
-		  __entry->block_tx, __entry->count, __entry->radar_required,
-		  __entry->counter_offset_beacon,
-		  __entry->counter_offset_presp)
+		  __entry->block_tx, __entry->count, __entry->radar_required)
 );
 
 TRACE_EVENT(rdev_set_qos_map,
-- 
2.0.0.rc0

[PATCH 4/8] mac80211: Support multiple CSA counters

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Support up to IEEE80211_MAX_CSA_COUNTERS_NUM csa counters.
This is defined to be 2 now, to support both CSA and eCSA
counters.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 net/mac80211/cfg.c         | 24 +++++++++++++------
 net/mac80211/ibss.c        |  2 +-
 net/mac80211/ieee80211_i.h |  6 +++--
 net/mac80211/main.c        |  2 ++
 net/mac80211/mesh.c        |  2 +-
 net/mac80211/tx.c          | 58 ++++++++++++++++++++++++++++------------------
 net/wireless/nl80211.c     |  4 ++--
 7 files changed, 63 insertions(+), 35 deletions(-)

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 6f132a5..43af0d6b 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3191,14 +3191,24 @@ static int ieee80211_set_csa_beacon(struct ieee80211_sub_if_data *sdata,
 		if (params->count <= 1)
 			break;
 
-		sdata->csa_counter_offset_beacon =
-			params->counter_offsets_beacon[0];
+		if ((params->n_counter_offsets_beacon >
+		     IEEE80211_MAX_CSA_COUNTERS_NUM) ||
+		    (params->n_counter_offsets_presp >
+		     IEEE80211_MAX_CSA_COUNTERS_NUM))
+			return -EINVAL;
 
-		if (params->n_counter_offsets_presp)
-			sdata->csa_counter_offset_presp =
-				params->counter_offsets_presp[0];
-		else
-			sdata->csa_counter_offset_presp = 0;
+		/* make sure we don't have garbage in other counters */
+		memset(sdata->csa_counter_offset_beacon, 0,
+		       sizeof(sdata->csa_counter_offset_beacon));
+		memset(sdata->csa_counter_offset_presp, 0,
+		       sizeof(sdata->csa_counter_offset_presp));
+
+		memcpy(sdata->csa_counter_offset_beacon,
+		       params->counter_offsets_beacon,
+		       params->n_counter_offsets_beacon * sizeof(u16));
+		memcpy(sdata->csa_counter_offset_presp,
+		       params->counter_offsets_presp,
+		       params->n_counter_offsets_presp * sizeof(u16));
 
 		err = ieee80211_assign_beacon(sdata, &params->beacon_csa);
 		if (err < 0) {
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index ff4d415..1bbac94 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -143,7 +143,7 @@ ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
 		*pos++ = csa_settings->block_tx ? 1 : 0;
 		*pos++ = ieee80211_frequency_to_channel(
 				csa_settings->chandef.chan->center_freq);
-		sdata->csa_counter_offset_beacon = (pos - presp->head);
+		sdata->csa_counter_offset_beacon[0] = (pos - presp->head);
 		*pos++ = csa_settings->count;
 	}
 
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index fb2d9e7..05ed592 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -70,6 +70,8 @@ struct ieee80211_local;
 
 #define IEEE80211_DEAUTH_FRAME_LEN	(24 /* hdr */ + 2 /* reason */)
 
+#define IEEE80211_MAX_CSA_COUNTERS_NUM 2
+
 struct ieee80211_fragment_entry {
 	unsigned long first_frag_time;
 	unsigned int seq;
@@ -753,8 +755,8 @@ struct ieee80211_sub_if_data {
 	struct mac80211_qos_map __rcu *qos_map;
 
 	struct work_struct csa_finalize_work;
-	int csa_counter_offset_beacon;
-	int csa_counter_offset_presp;
+	u16 csa_counter_offset_beacon[IEEE80211_MAX_CSA_COUNTERS_NUM];
+	u16 csa_counter_offset_presp[IEEE80211_MAX_CSA_COUNTERS_NUM];
 	bool csa_radar_required;
 	bool csa_block_tx; /* write-protected by sdata_lock and local->mtx */
 	struct cfg80211_chan_def csa_chandef;
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 69175f1..767335f 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -954,6 +954,8 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 	if (local->hw.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS)
 		local->hw.wiphy->flags |= WIPHY_FLAG_TDLS_EXTERNAL_SETUP;
 
+	local->hw.wiphy->max_num_csa_counters = IEEE80211_MAX_CSA_COUNTERS_NUM;
+
 	result = wiphy_register(local->hw.wiphy);
 	if (result < 0)
 		goto fail_wiphy_register;
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index b06ddc9..6495a3f 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -679,7 +679,7 @@ ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 		*pos++ = 0x0;
 		*pos++ = ieee80211_frequency_to_channel(
 				csa->settings.chandef.chan->center_freq);
-		sdata->csa_counter_offset_beacon = hdr_len + 6;
+		sdata->csa_counter_offset_beacon[0] = hdr_len + 6;
 		*pos++ = csa->settings.count;
 		*pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
 		*pos++ = 6;
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 263dea5..0d1a42d 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2417,10 +2417,9 @@ 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;
 	u8 *beacon_data;
 	size_t beacon_data_len;
+	int i;
 
 	switch (sdata->vif.type) {
 	case NL80211_IFTYPE_AP:
@@ -2438,32 +2437,47 @@ static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
 	default:
 		return;
 	}
-	if (WARN_ON(counter_offset_beacon >= beacon_data_len))
-		return;
 
-	/* Warn if the driver did not check for/react to csa
-	 * completeness.  A beacon with CSA counter set to 0 should
-	 * never occur, because a counter of 1 means switch just
-	 * before the next beacon.
-	 */
-	if (WARN_ON(beacon_data[counter_offset_beacon] == 1))
-		return;
+	for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; ++i) {
+		u16 counter_offset_beacon =
+			sdata->csa_counter_offset_beacon[i];
+		u16 counter_offset_presp = sdata->csa_counter_offset_presp[i];
 
-	sdata->csa_current_counter--;
-	beacon_data[counter_offset_beacon] = sdata->csa_current_counter;
+		if (counter_offset_beacon) {
+			if (WARN_ON(counter_offset_beacon >= beacon_data_len))
+				return;
 
-	if (sdata->vif.type == NL80211_IFTYPE_AP && counter_offset_presp) {
-		rcu_read_lock();
-		resp = rcu_dereference(sdata->u.ap.probe_resp);
+			/* Warn if the driver did not check for/react to csa
+			 * completeness.  A beacon with CSA counter set to 0
+			 * should never occur, because a counter of 1 means
+			 * switch just before the next beacon.
+			 */
+			if (WARN_ON(beacon_data[counter_offset_beacon] == 1))
+				return;
 
-		/* if nl80211 accepted the offset, this should not happen. */
-		if (WARN_ON(!resp)) {
+			beacon_data[counter_offset_beacon] =
+				sdata->csa_current_counter - 1;
+		}
+
+		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] =
+				sdata->csa_current_counter - 1;
 			rcu_read_unlock();
-			return;
 		}
-		resp->data[counter_offset_presp] = sdata->csa_current_counter;
-		rcu_read_unlock();
 	}
+
+	sdata->csa_current_counter--;
 }
 
 bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
@@ -2472,7 +2486,7 @@ bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
 	struct beacon_data *beacon = NULL;
 	u8 *beacon_data;
 	size_t beacon_data_len;
-	int counter_beacon = sdata->csa_counter_offset_beacon;
+	int counter_beacon = sdata->csa_counter_offset_beacon[0];
 	int ret = false;
 
 	if (!ieee80211_sdata_running(sdata))
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 6cfff9b..30ab799 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1669,9 +1669,9 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
 			nla_nest_end(msg, nested);
 		}
 
-		if (dev->wiphy.flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH &&
+		if (rdev->wiphy.flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH &&
 		    nla_put_u8(msg, NL80211_ATTR_MAX_CSA_COUNTERS,
-			       dev->wiphy.max_num_csa_counters))
+			       rdev->wiphy.max_num_csa_counters))
 			goto nla_put_failure;
 
 		/* done */
-- 
2.0.0.rc0

[PATCH 5/8] iwlwifi: mvm: Add AP/GO channel switch support

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Publish WIPHY_FLAG_HAS_CHANNEL_SWITCH if the fw supports
newly introduced IWL_UCODE_TLV_API_CSA_FLOW.
When CSA starts, save the switching vif inside mvm and during the CSA period
configure fw with a new beacon after each beacon transmission in order to
update the csa counters.
Also, handle correctly the CSA unbind-bind flow which is triggered by mac80211
when the actual channel switch happens.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 drivers/net/wireless/iwlwifi/iwl-fw.h       |  2 ++
 drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c | 12 ++++++++
 drivers/net/wireless/iwlwifi/mvm/mac80211.c | 44 ++++++++++++++++++++++++++++-
 drivers/net/wireless/iwlwifi/mvm/mvm.h      |  2 ++
 drivers/net/wireless/iwlwifi/mvm/ops.c      |  2 +-
 5 files changed, 60 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/iwl-fw.h b/drivers/net/wireless/iwlwifi/iwl-fw.h
index d14f193..946c13d 100644
--- a/drivers/net/wireless/iwlwifi/iwl-fw.h
+++ b/drivers/net/wireless/iwlwifi/iwl-fw.h
@@ -128,9 +128,11 @@ enum iwl_ucode_tlv_flag {
 /**
  * enum iwl_ucode_tlv_api - ucode api
  * @IWL_UCODE_TLV_API_WOWLAN_CONFIG_TID: wowlan config includes tid field.
+ * @IWL_UCODE_TLV_API_CSA_FLOW: ucode can do unbind-bind flow for CSA.
  */
 enum iwl_ucode_tlv_api {
 	IWL_UCODE_TLV_API_WOWLAN_CONFIG_TID	= BIT(0),
+	IWL_UCODE_TLV_API_CSA_FLOW		= BIT(4),
 };
 
 /**
diff --git a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
index 9ccec10..25901ad 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
@@ -1240,11 +1240,23 @@ int iwl_mvm_rx_beacon_notif(struct iwl_mvm *mvm,
 	u32 rate __maybe_unused =
 		le32_to_cpu(beacon->beacon_notify_hdr.initial_rate);
 
+	lockdep_assert_held(&mvm->mutex);
+
 	IWL_DEBUG_RX(mvm, "beacon status %#x retries:%d tsf:0x%16llX rate:%d\n",
 		     status & TX_STATUS_MSK,
 		     beacon->beacon_notify_hdr.failure_frame,
 		     le64_to_cpu(beacon->tsf),
 		     rate);
+
+	if (unlikely(mvm->csa_vif && mvm->csa_vif->csa_active)) {
+		if (!ieee80211_csa_is_complete(mvm->csa_vif)) {
+			iwl_mvm_mac_ctxt_beacon_changed(mvm, mvm->csa_vif);
+		} else {
+			ieee80211_csa_finish(mvm->csa_vif);
+			mvm->csa_vif = NULL;
+		}
+	}
+
 	return 0;
 }
 
diff --git a/drivers/net/wireless/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
index 4dd9ff4..af1d9da 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
@@ -322,6 +322,9 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
 	if (mvm->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_GO_UAPSD)
 		hw->wiphy->flags |= WIPHY_FLAG_AP_UAPSD;
 
+	if (mvm->fw->ucode_capa.api[0] & IWL_UCODE_TLV_API_CSA_FLOW)
+		hw->wiphy->flags |= WIPHY_FLAG_HAS_CHANNEL_SWITCH;
+
 	hw->wiphy->iface_combinations = iwl_mvm_iface_combinations;
 	hw->wiphy->n_iface_combinations =
 		ARRAY_SIZE(iwl_mvm_iface_combinations);
@@ -2178,6 +2181,11 @@ static int iwl_mvm_assign_vif_chanctx(struct ieee80211_hw *hw,
 
 	switch (vif->type) {
 	case NL80211_IFTYPE_AP:
+		/* Unless it's a CSA flow we have nothing to do here */
+		if (vif->csa_active) {
+			mvmvif->ap_ibss_active = true;
+			break;
+		}
 	case NL80211_IFTYPE_ADHOC:
 		/*
 		 * The AP binding flow is handled as part of the start_ap flow
@@ -2214,6 +2222,12 @@ static int iwl_mvm_assign_vif_chanctx(struct ieee80211_hw *hw,
 			goto out_remove_binding;
 	}
 
+	/* Handle binding during CSA */
+	if (vif->type == NL80211_IFTYPE_AP) {
+		iwl_mvm_update_quotas(mvm, vif);
+		iwl_mvm_mac_ctxt_changed(mvm, vif);
+	}
+
 	goto out_unlock;
 
  out_remove_binding:
@@ -2238,13 +2252,20 @@ static void iwl_mvm_unassign_vif_chanctx(struct ieee80211_hw *hw,
 	iwl_mvm_remove_time_event(mvm, mvmvif, &mvmvif->time_event_data);
 
 	switch (vif->type) {
-	case NL80211_IFTYPE_AP:
 	case NL80211_IFTYPE_ADHOC:
 		goto out_unlock;
 	case NL80211_IFTYPE_MONITOR:
 		mvmvif->monitor_active = false;
 		iwl_mvm_update_quotas(mvm, NULL);
 		break;
+	case NL80211_IFTYPE_AP:
+		/* This part is triggered only during CSA */
+		if (!vif->csa_active || !mvmvif->ap_ibss_active)
+			goto out_unlock;
+
+		mvmvif->ap_ibss_active = false;
+		iwl_mvm_update_quotas(mvm, NULL);
+		/*TODO: bt_coex notification here? */
 	default:
 		break;
 	}
@@ -2340,6 +2361,25 @@ static int iwl_mvm_mac_testmode_cmd(struct ieee80211_hw *hw,
 }
 #endif
 
+static void iwl_mvm_channel_switch_beacon(struct ieee80211_hw *hw,
+					  struct ieee80211_vif *vif,
+					  struct cfg80211_chan_def *chandef)
+{
+	struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
+
+	mutex_lock(&mvm->mutex);
+	if (WARN(mvm->csa_vif && mvm->csa_vif->csa_active,
+		 "Another CSA is already in progress"))
+		goto out_unlock;
+
+	IWL_DEBUG_MAC80211(mvm, "CSA started to freq %d\n",
+			   chandef->center_freq1);
+	mvm->csa_vif = vif;
+
+out_unlock:
+	mutex_unlock(&mvm->mutex);
+}
+
 const struct ieee80211_ops iwl_mvm_hw_ops = {
 	.tx = iwl_mvm_mac_tx,
 	.ampdu_action = iwl_mvm_mac_ampdu_action,
@@ -2382,6 +2422,8 @@ const struct ieee80211_ops iwl_mvm_hw_ops = {
 
 	.set_tim = iwl_mvm_set_tim,
 
+	.channel_switch_beacon = iwl_mvm_channel_switch_beacon,
+
 	CFG80211_TESTMODE_CMD(iwl_mvm_mac_testmode_cmd)
 
 #ifdef CONFIG_PM_SLEEP
diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h
index d564233..87f2105 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h
@@ -631,6 +631,8 @@ struct iwl_mvm {
 	bool ps_disabled;
 	/* Indicate if device power management is allowed */
 	bool pm_disabled;
+
+	struct ieee80211_vif *csa_vif;
 };
 
 /* Extract MVM priv from op_mode and _hw */
diff --git a/drivers/net/wireless/iwlwifi/mvm/ops.c b/drivers/net/wireless/iwlwifi/mvm/ops.c
index 9545d7f..729a857 100644
--- a/drivers/net/wireless/iwlwifi/mvm/ops.c
+++ b/drivers/net/wireless/iwlwifi/mvm/ops.c
@@ -220,7 +220,7 @@ static const struct iwl_rx_handlers iwl_mvm_rx_handlers[] = {
 	RX_HANDLER(BA_NOTIF, iwl_mvm_rx_ba_notif, false),
 
 	RX_HANDLER(BT_PROFILE_NOTIFICATION, iwl_mvm_rx_bt_coex_notif, true),
-	RX_HANDLER(BEACON_NOTIFICATION, iwl_mvm_rx_beacon_notif, false),
+	RX_HANDLER(BEACON_NOTIFICATION, iwl_mvm_rx_beacon_notif, true),
 	RX_HANDLER(STATISTICS_NOTIFICATION, iwl_mvm_rx_statistics, true),
 	RX_HANDLER(ANTENNA_COUPLING_NOTIFICATION,
 		   iwl_mvm_rx_ant_coupling_notif, true),
-- 
2.0.0.rc0

[PATCH 6/8] mac80211: Provide ieee80211_beacon_get_template API

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Add a new API ieee80211_beacon_get_template, which doesn't
affect DTIM counter and should be used if the device generates beacon
frames, and new beacon template is needed. In addition set the offsets
to TIM IE for MESH interface.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 include/net/mac80211.h | 43 ++++++++++++++++++++++-----
 net/mac80211/tx.c      | 80 ++++++++++++++++++++++++++++++++++++--------------
 2 files changed, 94 insertions(+), 29 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 3541c48..e652126 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -3412,6 +3412,39 @@ void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
 void ieee80211_report_low_ack(struct ieee80211_sta *sta, u32 num_packets);
 
 /**
+ * struct ieee80211_mutable_offsets - mutable beacon offsets
+ * @tim_offset: position of TIM element
+ * @tim_length: size of TIM element
+ */
+struct ieee80211_mutable_offsets {
+	u16 tim_offset;
+	u16 tim_length;
+};
+
+/**
+ * ieee80211_beacon_get_template - beacon template generation function
+ * @hw: pointer obtained from ieee80211_alloc_hw().
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
+ * @offs: &struct ieee80211_mutable_offsets pointer to struct that will
+ *	receive the offsets that may be updated by the driver.
+ *
+ * If the driver implements beaconing modes, it must use this function to
+ * obtain the beacon template.
+ *
+ * This function should be used if the beacon frames are generated by the
+ * device, and then the driver must use the returned beacon as the template
+ * The driver is responsible to update the DTIM count.
+ *
+ * The driver is responsible for freeing the returned skb.
+ *
+ * Return: The beacon template. %NULL on error.
+ */
+struct sk_buff *
+ieee80211_beacon_get_template(struct ieee80211_hw *hw,
+			      struct ieee80211_vif *vif,
+			      struct ieee80211_mutable_offsets *offs);
+
+/**
  * ieee80211_beacon_get_tim - beacon generation function
  * @hw: pointer obtained from ieee80211_alloc_hw().
  * @vif: &struct ieee80211_vif pointer from the add_interface callback.
@@ -3422,16 +3455,12 @@ void ieee80211_report_low_ack(struct ieee80211_sta *sta, u32 num_packets);
  *	Set to 0 if invalid (in non-AP modes).
  *
  * If the driver implements beaconing modes, it must use this function to
- * obtain the beacon frame/template.
+ * obtain the beacon frame.
  *
  * If the beacon frames are generated by the host system (i.e., not in
  * hardware/firmware), the driver uses this function to get each beacon
- * frame from mac80211 -- it is responsible for calling this function
- * before the beacon is needed (e.g. based on hardware interrupt).
- *
- * If the beacon frames are generated by the device, then the driver
- * must use the returned beacon as the template and change the TIM IE
- * according to the current DTIM parameters/TIM bitmap.
+ * frame from mac80211 -- it is responsible for calling this function exactly
+ * once before the beacon is needed (e.g. based on hardware interrupt).
  *
  * The driver is responsible for freeing the returned skb.
  *
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 0d1a42d..509456e 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2328,7 +2328,8 @@ void ieee80211_tx_pending(unsigned long data)
 /* functions for drivers to get certain frames */
 
 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
-				       struct ps_data *ps, struct sk_buff *skb)
+				       struct ps_data *ps, struct sk_buff *skb,
+				       bool is_template)
 {
 	u8 *pos, *tim;
 	int aid0 = 0;
@@ -2341,11 +2342,12 @@ static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
 		 * checking byte-for-byte */
 		have_bits = !bitmap_empty((unsigned long *)ps->tim,
 					  IEEE80211_MAX_AID+1);
-
-	if (ps->dtim_count == 0)
-		ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
-	else
-		ps->dtim_count--;
+	if (!is_template) {
+		if (ps->dtim_count == 0)
+			ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
+		else
+			ps->dtim_count--;
+	}
 
 	tim = pos = (u8 *) skb_put(skb, 6);
 	*pos++ = WLAN_EID_TIM;
@@ -2391,7 +2393,8 @@ static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
 }
 
 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
-				    struct ps_data *ps, struct sk_buff *skb)
+				    struct ps_data *ps, struct sk_buff *skb,
+				    bool is_template)
 {
 	struct ieee80211_local *local = sdata->local;
 
@@ -2403,10 +2406,10 @@ static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
 	 * of the tim bitmap in mac80211 and the driver.
 	 */
 	if (local->tim_in_locked_section) {
-		__ieee80211_beacon_add_tim(sdata, ps, skb);
+		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
 	} else {
 		spin_lock_bh(&local->tim_lock);
-		__ieee80211_beacon_add_tim(sdata, ps, skb);
+		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
 		spin_unlock_bh(&local->tim_lock);
 	}
 
@@ -2536,9 +2539,11 @@ bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
 }
 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)
+static struct sk_buff *
+__ieee80211_beacon_get(struct ieee80211_hw *hw,
+		       struct ieee80211_vif *vif,
+		       struct ieee80211_mutable_offsets *offs,
+		       bool is_template)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
 	struct sk_buff *skb = NULL;
@@ -2556,10 +2561,8 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
 		goto out;
 
-	if (tim_offset)
-		*tim_offset = 0;
-	if (tim_length)
-		*tim_length = 0;
+	if (offs)
+		memset(offs, 0, sizeof(*offs));
 
 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
 		struct ieee80211_if_ap *ap = &sdata->u.ap;
@@ -2584,12 +2587,13 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
 			       beacon->head_len);
 
-			ieee80211_beacon_add_tim(sdata, &ap->ps, skb);
+			ieee80211_beacon_add_tim(sdata, &ap->ps, skb,
+						 is_template);
 
-			if (tim_offset)
-				*tim_offset = beacon->head_len;
-			if (tim_length)
-				*tim_length = skb->len - beacon->head_len;
+			if (offs) {
+				offs->tim_offset = beacon->head_len;
+				offs->tim_length = skb->len - beacon->head_len;
+			}
 
 			if (beacon->tail)
 				memcpy(skb_put(skb, beacon->tail_len),
@@ -2641,7 +2645,13 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 			goto out;
 		skb_reserve(skb, local->tx_headroom);
 		memcpy(skb_put(skb, bcn->head_len), bcn->head, bcn->head_len);
-		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb);
+		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb, is_template);
+
+		if (offs) {
+			offs->tim_offset = bcn->head_len;
+			offs->tim_length = skb->len - bcn->head_len;
+		}
+
 		memcpy(skb_put(skb, bcn->tail_len), bcn->tail, bcn->tail_len);
 	} else {
 		WARN_ON(1);
@@ -2678,6 +2688,32 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
  out:
 	rcu_read_unlock();
 	return skb;
+
+}
+
+struct sk_buff *
+ieee80211_beacon_get_template(struct ieee80211_hw *hw,
+			      struct ieee80211_vif *vif,
+			      struct ieee80211_mutable_offsets *offs)
+{
+	return __ieee80211_beacon_get(hw, vif, offs, true);
+}
+EXPORT_SYMBOL(ieee80211_beacon_get_template);
+
+struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
+					 struct ieee80211_vif *vif,
+					 u16 *tim_offset, u16 *tim_length)
+{
+	struct ieee80211_mutable_offsets offs = {};
+	struct sk_buff *bcn = __ieee80211_beacon_get(hw, vif, &offs, false);
+
+	if (tim_offset)
+		*tim_offset = offs.tim_offset;
+
+	if (tim_length)
+		*tim_length = offs.tim_length;
+
+	return bcn;
 }
 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
 
-- 
2.0.0.rc0

[PATCH 7/8] mac80211: Handle the CSA counters correctly

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Make the beacon CSA counters part of ieee80211_mutable_offsets and don't
decrement CSA counters when generating a beacon template. This permits the
driver to offload the CSA counters handling. Since mac80211 updates the probe
responses with the correct counter, the driver should sync the counter's value
with mac80211 using ieee80211_csa_update_counter function.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 include/net/mac80211.h     | 23 +++++++++++++-
 net/mac80211/cfg.c         |  4 +--
 net/mac80211/ieee80211_i.h |  2 --
 net/mac80211/tx.c          | 76 ++++++++++++++++++++++++++++++++++------------
 4 files changed, 80 insertions(+), 25 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index e652126..982d2cd 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -3411,14 +3411,20 @@ void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
  */
 void ieee80211_report_low_ack(struct ieee80211_sta *sta, u32 num_packets);
 
+#define IEEE80211_MAX_CSA_COUNTERS_NUM 2
+
 /**
  * struct ieee80211_mutable_offsets - mutable beacon offsets
  * @tim_offset: position of TIM element
  * @tim_length: size of TIM element
+ * @csa_offs: array of IEEE80211_MAX_CSA_COUNTERS_NUM offsets to CSA counters.
+ *	This array can contain zero values which should be ignored.
  */
 struct ieee80211_mutable_offsets {
 	u16 tim_offset;
 	u16 tim_length;
+
+	u16 csa_counter_offs[IEEE80211_MAX_CSA_COUNTERS_NUM];
 };
 
 /**
@@ -3433,7 +3439,8 @@ struct ieee80211_mutable_offsets {
  *
  * This function should be used if the beacon frames are generated by the
  * device, and then the driver must use the returned beacon as the template
- * The driver is responsible to update the DTIM count.
+ * The driver or the device are responsible to update the DTIM and, when
+ * applicable, the CSA count.
  *
  * The driver is responsible for freeing the returned skb.
  *
@@ -3486,6 +3493,20 @@ static inline struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
 }
 
 /**
+ * ieee80211_csa_update_counter - request mac80211 to decrement the csa counter
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
+ *
+ * The csa counter should be updated after each beacon transmission.
+ * This function is called implicitly when
+ * ieee80211_beacon_get/ieee80211_beacon_get_tim are called, however if the
+ * beacon frames are generated by the device, the driver should call this
+ * function after each beacon transmission to sync mac80211's csa counters.
+ *
+ * Return: new csa counter value
+ */
+u8 ieee80211_csa_update_counter(struct ieee80211_vif *vif);
+
+/**
  * ieee80211_csa_finish - notify mac80211 about channel switch
  * @vif: &struct ieee80211_vif pointer from the add_interface callback.
  *
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 43af0d6b..4584765 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3502,10 +3502,10 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
 	     sdata->vif.type == NL80211_IFTYPE_ADHOC) &&
 	    params->n_csa_offsets) {
 		int i;
+		u8 c = sdata->csa_current_counter;
 
 		for (i = 0; i < params->n_csa_offsets; i++)
-			data[params->csa_offsets[i]] =
-					sdata->csa_current_counter;
+			data[params->csa_offsets[i]] = c;
 	}
 	IEEE80211_SKB_CB(skb)->flags = flags;
 
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 05ed592..57e0b26 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -70,8 +70,6 @@ struct ieee80211_local;
 
 #define IEEE80211_DEAUTH_FRAME_LEN	(24 /* hdr */ + 2 /* reason */)
 
-#define IEEE80211_MAX_CSA_COUNTERS_NUM 2
-
 struct ieee80211_fragment_entry {
 	unsigned long first_frag_time;
 	unsigned int seq;
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 509456e..5214686 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2416,13 +2416,14 @@ static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
 	return 0;
 }
 
-static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
-				 struct beacon_data *beacon)
+static void ieee80211_set_csa(struct ieee80211_sub_if_data *sdata,
+			      struct beacon_data *beacon)
 {
 	struct probe_resp *resp;
 	u8 *beacon_data;
 	size_t beacon_data_len;
 	int i;
+	u8 count = sdata->csa_current_counter;
 
 	switch (sdata->vif.type) {
 	case NL80211_IFTYPE_AP:
@@ -2450,16 +2451,7 @@ static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
 			if (WARN_ON(counter_offset_beacon >= beacon_data_len))
 				return;
 
-			/* Warn if the driver did not check for/react to csa
-			 * completeness.  A beacon with CSA counter set to 0
-			 * should never occur, because a counter of 1 means
-			 * switch just before the next beacon.
-			 */
-			if (WARN_ON(beacon_data[counter_offset_beacon] == 1))
-				return;
-
-			beacon_data[counter_offset_beacon] =
-				sdata->csa_current_counter - 1;
+			beacon_data[counter_offset_beacon] = count;
 		}
 
 		if (sdata->vif.type == NL80211_IFTYPE_AP &&
@@ -2474,14 +2466,24 @@ static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
 				rcu_read_unlock();
 				return;
 			}
-			resp->data[counter_offset_presp] =
-				sdata->csa_current_counter - 1;
+			resp->data[counter_offset_presp] = count;
 			rcu_read_unlock();
 		}
 	}
+}
+
+u8 ieee80211_csa_update_counter(struct ieee80211_vif *vif)
+{
+	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 
 	sdata->csa_current_counter--;
+
+	/* the counter should never reach 0 */
+	WARN_ON(!sdata->csa_current_counter);
+
+	return sdata->csa_current_counter;
 }
+EXPORT_SYMBOL(ieee80211_csa_update_counter);
 
 bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
 {
@@ -2552,6 +2554,7 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 	enum ieee80211_band band;
 	struct ieee80211_tx_rate_control txrc;
 	struct ieee80211_chanctx_conf *chanctx_conf;
+	int csa_off_base = 0;
 
 	rcu_read_lock();
 
@@ -2569,8 +2572,12 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 		struct beacon_data *beacon = rcu_dereference(ap->beacon);
 
 		if (beacon) {
-			if (sdata->vif.csa_active)
-				ieee80211_update_csa(sdata, beacon);
+			if (sdata->vif.csa_active) {
+				if (!is_template)
+					ieee80211_csa_update_counter(vif);
+
+				ieee80211_set_csa(sdata, beacon);
+			}
 
 			/*
 			 * headroom, head length,
@@ -2593,6 +2600,9 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 			if (offs) {
 				offs->tim_offset = beacon->head_len;
 				offs->tim_length = skb->len - beacon->head_len;
+
+				/* for AP the csa offsets are from tail */
+				csa_off_base = skb->len;
 			}
 
 			if (beacon->tail)
@@ -2608,9 +2618,12 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 		if (!presp)
 			goto out;
 
-		if (sdata->vif.csa_active)
-			ieee80211_update_csa(sdata, presp);
+		if (sdata->vif.csa_active) {
+			if (!is_template)
+				ieee80211_csa_update_counter(vif);
 
+			ieee80211_set_csa(sdata, presp);
+		}
 
 		skb = dev_alloc_skb(local->tx_headroom + presp->head_len +
 				    local->hw.extra_beacon_tailroom);
@@ -2630,8 +2643,17 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 		if (!bcn)
 			goto out;
 
-		if (sdata->vif.csa_active)
-			ieee80211_update_csa(sdata, bcn);
+		if (sdata->vif.csa_active) {
+			if (!is_template)
+				/* TODO: For mesh csa_counter is in TU, so
+				 * decrementing it by one isn't correct, but
+				 * for now we leave it consistent with overall
+				 * mac80211's behavior.
+				 */
+				ieee80211_csa_update_counter(vif);
+
+			ieee80211_set_csa(sdata, bcn);
+		}
 
 		if (ifmsh->sync_ops)
 			ifmsh->sync_ops->adjust_tbtt(sdata, bcn);
@@ -2658,6 +2680,20 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 		goto out;
 	}
 
+	/* CSA offsets */
+	if (offs) {
+		int i;
+
+		for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; i++) {
+			u16 csa_off = sdata->csa_counter_offset_beacon[i];
+
+			if (!csa_off)
+				continue;
+
+			offs->csa_counter_offs[i] = csa_off_base + csa_off;
+		}
+	}
+
 	band = chanctx_conf->def.chan->band;
 
 	info = IEEE80211_SKB_CB(skb);
-- 
2.0.0.rc0

[PATCH 8/8] iwlwifi: mvm: Use beacon_get_template instead of beacon_get

[Luca Coelho]

From: Andrei Otcheretianski <andrei.otcheretianski@intel.com>

Call ieee80211_beacon_get_template instead of ieee80211_beacon_get and sync the
CSA counters with mac80211 after each beacon transmission.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
---
 drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
index 25901ad..9b73a85 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
@@ -997,7 +997,7 @@ int iwl_mvm_mac_ctxt_beacon_changed(struct iwl_mvm *mvm,
 	WARN_ON(vif->type != NL80211_IFTYPE_AP &&
 		vif->type != NL80211_IFTYPE_ADHOC);
 
-	beacon = ieee80211_beacon_get(mvm->hw, vif);
+	beacon = ieee80211_beacon_get_template(mvm->hw, vif, NULL);
 	if (!beacon)
 		return -ENOMEM;
 
@@ -1250,6 +1250,7 @@ int iwl_mvm_rx_beacon_notif(struct iwl_mvm *mvm,
 
 	if (unlikely(mvm->csa_vif && mvm->csa_vif->csa_active)) {
 		if (!ieee80211_csa_is_complete(mvm->csa_vif)) {
+			ieee80211_csa_update_counter(mvm->csa_vif);
 			iwl_mvm_mac_ctxt_beacon_changed(mvm, mvm->csa_vif);
 		} else {
 			ieee80211_csa_finish(mvm->csa_vif);
-- 
2.0.0.rc0

Re: [PATCH 0/8] mac80211/cfg80211/iwlwifi: a few channel-switch patches

[Johannes Berg]

On Fri, 2014-05-09 at 14:11 +0300, Luca Coelho wrote:
> From: Luciano Coelho <luciano.coelho@intel.com>
> 
> Hi,
> 
> These are a few channel-switch patches by Andrei that we have in our
> internal tree.  I have rebased them for upstream.

Applied the cfg80211/mac80211 changes, but please ... that cover letter
was useless, and your patch set had build breakage in the middle. :)

I fixed that with along with some minor editing changes and a change to
the netlink dump as well.

johannes

Re: [PATCH 0/8] mac80211/cfg80211/iwlwifi: a few channel-switch patches

[Luca Coelho]

On Thu, 2014-05-15 at 15:11 +0200, Johannes Berg wrote:
> On Fri, 2014-05-09 at 14:11 +0300, Luca Coelho wrote:
> > From: Luciano Coelho <luciano.coelho@intel.com>
> > 
> > Hi,
> > 
> > These are a few channel-switch patches by Andrei that we have in our
> > internal tree.  I have rebased them for upstream.
> 
> Applied the cfg80211/mac80211 changes, but please ... that cover letter
> was useless,

Yes, it was a bit useless in terms of content, but I like to group
things and reckoned it would be nice to explain why I was sending
Andrei's patches.  Also, I like the fact that you can reply to the cover
letter saying that you applied everything (or not) instead of replying
to one of the actual patches (say 1/8).

>  and your patch set had build breakage in the middle. :)

Oh, really? Sorry about that... I probably screwed up the rebase...

> I fixed that with along with some minor editing changes and a change to
> the netlink dump as well.

Thanks!

Maybe next time I should not volunteer to send other people's patches
upstream.  I do enough breakage with my own stuff! :P

--
Luca.