[PATCH v10 1/2] wireless: Support ht-capabilities over-rides.

[PATCH v10 1/2] wireless: Support ht-capabilities over-rides.

[greearb]

From: Ben Greear <greearb@candelatech.com>

This allows users to disable features such as HT, HT40,
and to modify the MCS, AMPDU, and AMSDU settings for
drivers that support it.

The MCS, AMPDU, and AMSDU features that may be disabled are
are reported in the phy-info netlink message as a mask.

Attemping to disable features that are not supported will
take no affect, but will not return errors.  This is to aid
backwards compatibility in user-space apps that may not be
clever enough to deal with parsing the the capabilities mask.

This patch only enables the infrastructure.  An additional
patch will enable the feature in mac80211.

Signed-off-by: Ben Greear <greearb@candelatech.com>
---

v10:  No changes since v9

:100644 100644 f9261c2... 0df2062... M	include/linux/nl80211.h
:100644 100644 8d7ba09... 4f6d131... M	include/net/cfg80211.h
:100644 100644 1c7d4df... fb08c28... M	net/wireless/core.h
:100644 100644 6c1bafd... 438dfc1... M	net/wireless/mlme.c
:100644 100644 6bc7c4b... aa98ec2... M	net/wireless/nl80211.c
:100644 100644 0acfdc9... f0c900c... M	net/wireless/sme.c
 include/linux/nl80211.h |   14 ++++++++++++++
 include/net/cfg80211.h  |   27 +++++++++++++++++++++++++++
 net/wireless/core.h     |   10 ++++++++--
 net/wireless/mlme.c     |   37 ++++++++++++++++++++++++++++++++++---
 net/wireless/nl80211.c  |   44 +++++++++++++++++++++++++++++++++++++++++++-
 net/wireless/sme.c      |    7 ++++++-
 6 files changed, 132 insertions(+), 7 deletions(-)

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index f9261c2..0df2062 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -1169,6 +1169,17 @@ enum nl80211_commands {
  * @NL80211_ATTR_PROBE_RESP: Probe Response template data. Contains the entire
  *	probe-response frame. The DA field in the 802.11 header is zero-ed out,
  *	to be filled by the FW.
+ * @NL80211_ATTR_DISABLE_HT:  Force HT capable interfaces to disable
+ *      this feature.  Currently, only supported in mac80211 drivers.
+ * @NL80211_ATTR_HT_CAPABILITY_MASK: Specify which bits of the
+ *      ATTR_HT_CAPABILITY to which attention should be paid.
+ *      Currently, only mac80211 NICs support this feature.
+ *      The values that may be configured are:
+ *       MCS rates, MAX-AMSDU, HT-20-40 and HT_CAP_SGI_40
+ *       AMPDU density and AMPDU factor.
+ *      All values are treated as suggestions and may be ignored
+ *      by the driver as required.  The actual values may be seen in
+ *      the station debugfs ht_caps file.
  *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -1408,6 +1419,9 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_PROBE_RESP,
 
+	NL80211_ATTR_DISABLE_HT,
+	NL80211_ATTR_HT_CAPABILITY_MASK,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 8d7ba09..4f6d131 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1044,6 +1044,15 @@ struct cfg80211_auth_request {
 };
 
 /**
+ * enum cfg80211_assoc_req_flags - Over-ride default behaviour in association.
+ *
+ * @ASSOC_REQ_DISABLE_HT:  Disable HT (802.11n)
+ */
+enum cfg80211_assoc_req_flags {
+	ASSOC_REQ_DISABLE_HT		= BIT(0),
+};
+
+/**
  * struct cfg80211_assoc_request - (Re)Association request data
  *
  * This structure provides information needed to complete IEEE 802.11
@@ -1054,6 +1063,10 @@ struct cfg80211_auth_request {
  * @use_mfp: Use management frame protection (IEEE 802.11w) in this association
  * @crypto: crypto settings
  * @prev_bssid: previous BSSID, if not %NULL use reassociate frame
+ * @flags:  See &enum cfg80211_assoc_req_flags
+ * @ht_capa:  HT Capabilities over-rides.  Values set in ht_capa_mask
+ *   will be used in ht_capa.  Un-supported values will be ignored.
+ * @ht_capa_mask:  The bits of ht_capa which are to be used.
  */
 struct cfg80211_assoc_request {
 	struct cfg80211_bss *bss;
@@ -1061,6 +1074,9 @@ struct cfg80211_assoc_request {
 	size_t ie_len;
 	struct cfg80211_crypto_settings crypto;
 	bool use_mfp;
+	u32 flags;
+	struct ieee80211_ht_cap ht_capa;
+	struct ieee80211_ht_cap ht_capa_mask;
 };
 
 /**
@@ -1159,6 +1175,10 @@ struct cfg80211_ibss_params {
  * @key_len: length of WEP key for shared key authentication
  * @key_idx: index of WEP key for shared key authentication
  * @key: WEP key for shared key authentication
+ * @flags:  See &enum cfg80211_assoc_req_flags
+ * @ht_capa:  HT Capabilities over-rides.  Values set in ht_capa_mask
+ *   will be used in ht_capa.  Un-supported values will be ignored.
+ * @ht_capa_mask:  The bits of ht_capa which are to be used.
  */
 struct cfg80211_connect_params {
 	struct ieee80211_channel *channel;
@@ -1172,6 +1192,9 @@ struct cfg80211_connect_params {
 	struct cfg80211_crypto_settings crypto;
 	const u8 *key;
 	u8 key_len, key_idx;
+	u32 flags;
+	struct ieee80211_ht_cap ht_capa;
+	struct ieee80211_ht_cap ht_capa_mask;
 };
 
 /**
@@ -1934,6 +1957,8 @@ struct wiphy_wowlan_support {
  * @wowlan: WoWLAN support information
  *
  * @ap_sme_capa: AP SME capabilities, flags from &enum nl80211_ap_sme_features.
+ * @ht_capa_mod_mask:  Specify what ht_cap values can be over-ridden.
+ *	If null, then none can be over-ridden.
  */
 struct wiphy {
 	/* assign these fields before you register the wiphy */
@@ -2023,6 +2048,8 @@ struct wiphy {
 	/* dir in debugfs: ieee80211/<wiphyname> */
 	struct dentry *debugfsdir;
 
+	const struct ieee80211_ht_cap *ht_capa_mod_mask;
+
 #ifdef CONFIG_NET_NS
 	/* the network namespace this phy lives in currently */
 	struct net *_net;
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 1c7d4df..fb08c28 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -341,13 +341,17 @@ int __cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 			  const u8 *bssid, const u8 *prev_bssid,
 			  const u8 *ssid, int ssid_len,
 			  const u8 *ie, int ie_len, bool use_mfp,
-			  struct cfg80211_crypto_settings *crypt);
+			  struct cfg80211_crypto_settings *crypt,
+			  u32 assoc_flags, struct ieee80211_ht_cap *ht_capa,
+			  struct ieee80211_ht_cap *ht_capa_mask);
 int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 			struct net_device *dev, struct ieee80211_channel *chan,
 			const u8 *bssid, const u8 *prev_bssid,
 			const u8 *ssid, int ssid_len,
 			const u8 *ie, int ie_len, bool use_mfp,
-			struct cfg80211_crypto_settings *crypt);
+			struct cfg80211_crypto_settings *crypt,
+			u32 assoc_flags, struct ieee80211_ht_cap *ht_capa,
+			struct ieee80211_ht_cap *ht_capa_mask);
 int __cfg80211_mlme_deauth(struct cfg80211_registered_device *rdev,
 			   struct net_device *dev, const u8 *bssid,
 			   const u8 *ie, int ie_len, u16 reason,
@@ -379,6 +383,8 @@ int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev,
 			  bool channel_type_valid, unsigned int wait,
 			  const u8 *buf, size_t len, bool no_cck,
 			  bool dont_wait_for_ack, u64 *cookie);
+void cfg80211_oper_and_ht_capa(struct ieee80211_ht_cap *ht_capa,
+			       const struct ieee80211_ht_cap *ht_capa_mask);
 
 /* SME */
 int __cfg80211_connect(struct cfg80211_registered_device *rdev,
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 6c1bafd..438dfc1 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -501,13 +501,32 @@ int cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
 	return err;
 }
 
+/*  Do a logical ht_capa &= ht_capa_mask.  */
+void cfg80211_oper_and_ht_capa(struct ieee80211_ht_cap *ht_capa,
+			       const struct ieee80211_ht_cap *ht_capa_mask)
+{
+	int i;
+	u8 *p1, *p2;
+	if (!ht_capa_mask) {
+		memset(ht_capa, 0, sizeof(*ht_capa));
+		return;
+	}
+
+	p1 = (u8*)(ht_capa);
+	p2 = (u8*)(ht_capa_mask);
+	for (i = 0; i<sizeof(*ht_capa); i++)
+		p1[i] &= p2[i];
+}
+
 int __cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 			  struct net_device *dev,
 			  struct ieee80211_channel *chan,
 			  const u8 *bssid, const u8 *prev_bssid,
 			  const u8 *ssid, int ssid_len,
 			  const u8 *ie, int ie_len, bool use_mfp,
-			  struct cfg80211_crypto_settings *crypt)
+			  struct cfg80211_crypto_settings *crypt,
+			  u32 assoc_flags, struct ieee80211_ht_cap *ht_capa,
+			  struct ieee80211_ht_cap *ht_capa_mask)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct cfg80211_assoc_request req;
@@ -537,6 +556,15 @@ int __cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 	memcpy(&req.crypto, crypt, sizeof(req.crypto));
 	req.use_mfp = use_mfp;
 	req.prev_bssid = prev_bssid;
+	req.flags = assoc_flags;
+	if (ht_capa)
+		memcpy(&req.ht_capa, ht_capa, sizeof(req.ht_capa));
+	if (ht_capa_mask)
+		memcpy(&req.ht_capa_mask, ht_capa_mask,
+		       sizeof(req.ht_capa_mask));
+	cfg80211_oper_and_ht_capa(&req.ht_capa_mask,
+				  rdev->wiphy.ht_capa_mod_mask);
+
 	req.bss = cfg80211_get_bss(&rdev->wiphy, chan, bssid, ssid, ssid_len,
 				   WLAN_CAPABILITY_ESS, WLAN_CAPABILITY_ESS);
 	if (!req.bss) {
@@ -574,14 +602,17 @@ int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 			const u8 *bssid, const u8 *prev_bssid,
 			const u8 *ssid, int ssid_len,
 			const u8 *ie, int ie_len, bool use_mfp,
-			struct cfg80211_crypto_settings *crypt)
+			struct cfg80211_crypto_settings *crypt,
+			u32 assoc_flags, struct ieee80211_ht_cap *ht_capa,
+			struct ieee80211_ht_cap *ht_capa_mask)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	int err;
 
 	wdev_lock(wdev);
 	err = __cfg80211_mlme_assoc(rdev, dev, chan, bssid, prev_bssid,
-				    ssid, ssid_len, ie, ie_len, use_mfp, crypt);
+				    ssid, ssid_len, ie, ie_len, use_mfp, crypt,
+				    assoc_flags, ht_capa, ht_capa_mask);
 	wdev_unlock(wdev);
 
 	return err;
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 6bc7c4b..aa98ec2 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -199,6 +199,10 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
 	[NL80211_ATTR_DONT_WAIT_FOR_ACK] = { .type = NLA_FLAG },
 	[NL80211_ATTR_PROBE_RESP] = { .type = NLA_BINARY,
 				      .len = IEEE80211_MAX_DATA_LEN },
+	[NL80211_ATTR_DISABLE_HT] = { .type = NLA_FLAG },
+	[NL80211_ATTR_HT_CAPABILITY_MASK] = {
+		.len = NL80211_HT_CAPABILITY_LEN
+	},
 };
 
 /* policy for the key attributes */
@@ -1025,6 +1029,11 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 
 	NLA_PUT_U32(msg, NL80211_ATTR_FEATURE_FLAGS, dev->wiphy.features);
 
+	if (dev->wiphy.ht_capa_mod_mask)
+		NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY_MASK,
+			sizeof(*dev->wiphy.ht_capa_mod_mask),
+			dev->wiphy.ht_capa_mod_mask);
+
 	return genlmsg_end(msg, hdr);
 
  nla_put_failure:
@@ -4384,6 +4393,9 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
 	const u8 *bssid, *ssid, *ie = NULL, *prev_bssid = NULL;
 	int err, ssid_len, ie_len = 0;
 	bool use_mfp = false;
+	u32 flags = 0;
+	struct ieee80211_ht_cap *ht_capa = NULL;
+	struct ieee80211_ht_cap *ht_capa_mask = NULL;
 
 	if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
 		return -EINVAL;
@@ -4427,11 +4439,25 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
 	if (info->attrs[NL80211_ATTR_PREV_BSSID])
 		prev_bssid = nla_data(info->attrs[NL80211_ATTR_PREV_BSSID]);
 
+	if (nla_get_flag(info->attrs[NL80211_ATTR_DISABLE_HT]))
+		flags |= ASSOC_REQ_DISABLE_HT;
+
+	if (info->attrs[NL80211_ATTR_HT_CAPABILITY_MASK])
+		ht_capa_mask =
+			nla_data(info->attrs[NL80211_ATTR_HT_CAPABILITY_MASK]);
+
+	if (info->attrs[NL80211_ATTR_HT_CAPABILITY]) {
+		if (!ht_capa_mask)
+			return -EINVAL;
+		ht_capa = nla_data(info->attrs[NL80211_ATTR_HT_CAPABILITY]);
+	}
+
 	err = nl80211_crypto_settings(rdev, info, &crypto, 1);
 	if (!err)
 		err = cfg80211_mlme_assoc(rdev, dev, chan, bssid, prev_bssid,
 					  ssid, ssid_len, ie, ie_len, use_mfp,
-					  &crypto);
+					  &crypto, flags, ht_capa,
+					  ht_capa_mask);
 
 	return err;
 }
@@ -4921,6 +4947,22 @@ static int nl80211_connect(struct sk_buff *skb, struct genl_info *info)
 			return PTR_ERR(connkeys);
 	}
 
+	if (nla_get_flag(info->attrs[NL80211_ATTR_DISABLE_HT]))
+		connect.flags |= ASSOC_REQ_DISABLE_HT;
+
+	if (info->attrs[NL80211_ATTR_HT_CAPABILITY_MASK])
+		memcpy(&connect.ht_capa_mask,
+		       nla_data(info->attrs[NL80211_ATTR_HT_CAPABILITY_MASK]),
+		       sizeof(connect.ht_capa_mask));
+
+	if (info->attrs[NL80211_ATTR_HT_CAPABILITY]) {
+		if (!info->attrs[NL80211_ATTR_HT_CAPABILITY_MASK])
+			return -EINVAL;
+		memcpy(&connect.ht_capa,
+		       nla_data(info->attrs[NL80211_ATTR_HT_CAPABILITY]),
+		       sizeof(connect.ht_capa));
+	}
+
 	err = cfg80211_connect(rdev, dev, &connect, connkeys);
 	if (err)
 		kfree(connkeys);
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index 0acfdc9..f0c900c 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -190,7 +190,9 @@ static int cfg80211_conn_do_work(struct wireless_dev *wdev)
 					    prev_bssid,
 					    params->ssid, params->ssid_len,
 					    params->ie, params->ie_len,
-					    false, &params->crypto);
+					    false, &params->crypto,
+					    params->flags, &params->ht_capa,
+					    &params->ht_capa_mask);
 		if (err)
 			__cfg80211_mlme_deauth(rdev, wdev->netdev, params->bssid,
 					       NULL, 0,
@@ -774,6 +776,9 @@ int __cfg80211_connect(struct cfg80211_registered_device *rdev,
 		wdev->connect_keys = NULL;
 	}
 
+	cfg80211_oper_and_ht_capa(&connect->ht_capa_mask,
+				  rdev->wiphy.ht_capa_mod_mask);
+
 	if (connkeys && connkeys->def >= 0) {
 		int idx;
 		u32 cipher;
-- 
1.7.3.4

[PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[greearb]

From: Ben Greear <greearb@candelatech.com>

This implements ht-cap over-rides for mac80211 drivers.
HT may be disabled, making an /a/b/g/n station act like an
a/b/g station.  HT40 may be disabled forcing the station to
be HT20 even if the AP and local hardware support HT40.

MAX-AMSDU may be disabled.
AMPDU-Density may be increased.
AMPDU-Factor may be decreased.

This has been successfully tested with ath9k using patched
wpa_supplicant and iw.

Signed-off-by: Ben Greear <greearb@candelatech.com>
---

v10:
 *  Add check in ieee80211_apply_htcap_overrides to make
    sure we are type NL80211_IFTYPE_STATION.

 *  Memset u.mgd.ht_capa and ht_capa_mask to 0 in
    ieee80211_set_disassoc to make sure we do not try to
    use stale data.

 *  Add cpu_to_le16 when dealing with u.mgd.ht_capa*
    Appears to make no change on x86, but should help
    with certain other platforms.

 *  Addressed other issues brought up in review of v9.


:100644 100644 1063a7e... 2577c45... M	net/mac80211/cfg.c
:100644 100644 d069750... 810cfbe... M	net/mac80211/ht.c
:100644 100644 068cc92... 2ecaf2d... M	net/mac80211/ieee80211_i.h
:100644 100644 e323d4e... e610103... M	net/mac80211/main.c
:100644 100644 b3a125f... ee82d2f... M	net/mac80211/mesh.c
:100644 100644 0140e88... 7314372b.. M	net/mac80211/mesh_plink.c
:100644 100644 9d1fb85... 193cda5... M	net/mac80211/mlme.c
:100644 100644 3a00814... 1c489bb... M	net/mac80211/util.c
:100644 100644 3dd5a89... 6884a2d... M	net/mac80211/work.c
 net/mac80211/cfg.c         |    2 +-
 net/mac80211/ht.c          |   83 +++++++++++++++++++++++++++++++++++++++++++-
 net/mac80211/ieee80211_i.h |   11 +++++-
 net/mac80211/main.c        |   14 +++++++
 net/mac80211/mesh.c        |    2 +-
 net/mac80211/mesh_plink.c  |    3 +-
 net/mac80211/mlme.c        |   14 ++++++-
 net/mac80211/util.c        |   13 ++++---
 net/mac80211/work.c        |   16 ++++++--
 9 files changed, 140 insertions(+), 18 deletions(-)

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 1063a7e..2577c45 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -832,7 +832,7 @@ static void sta_apply_parameters(struct ieee80211_local *local,
 	}
 
 	if (params->ht_capa)
-		ieee80211_ht_cap_ie_to_sta_ht_cap(sband,
+		ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 						  params->ht_capa,
 						  &sta->sta.ht_cap);
 
diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index d069750..810cfbe 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -19,7 +19,82 @@
 #include "ieee80211_i.h"
 #include "rate.h"
 
-void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
+bool ieee80111_cfg_override_disables_ht40(struct ieee80211_sub_if_data *sdata)
+{
+	const __le16 flg = cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40);
+	if ((sdata->u.mgd.ht_capa_mask.cap_info & flg) &&
+	    !(sdata->u.mgd.ht_capa.cap_info & flg))
+		return true;
+	return false;
+}
+
+void __check_htcap_disable(struct ieee80211_sub_if_data *sdata,
+			   struct ieee80211_sta_ht_cap *ht_cap,
+			   u16 flag)
+{
+	__le16 le_flag = cpu_to_le16(flag);
+	if (sdata->u.mgd.ht_capa_mask.cap_info & le_flag) {
+		if (!(sdata->u.mgd.ht_capa.cap_info & le_flag))
+			ht_cap->cap &= ~flag;
+	}
+}
+
+void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
+				     struct ieee80211_sta_ht_cap *ht_cap)
+{
+	u8 *scaps = (u8 *)(&sdata->u.mgd.ht_capa.mcs.rx_mask);
+	u8 *smask = (u8 *)(&sdata->u.mgd.ht_capa_mask.mcs.rx_mask);
+	int i;
+
+	if (sdata->vif.type != NL80211_IFTYPE_STATION) {
+		WARN_ON_ONCE(sdata->vif.type != NL80211_IFTYPE_STATION);
+		return;
+	}
+
+	/* NOTE:  If you add more over-rides here, update register_hw
+	 * ht_capa_mod_msk logic in main.c as well.
+	 * And, if this method can ever change ht_cap.ht_supported, fix
+	 * the check in ieee80211_add_ht_ie.
+	 */
+
+	/* check for HT over-rides, MCS rates first. */
+	for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
+		u8 m = smask[i];
+		ht_cap->mcs.rx_mask[i] &= ~m; /* turn off all masked bits */
+		/* Add back rates that are supported */
+		ht_cap->mcs.rx_mask[i] |= (m & scaps[i]);
+	}
+
+	/* Force removal of HT-40 capabilities? */
+	__check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_SUP_WIDTH_20_40);
+	__check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_SGI_40);
+
+	/* Allow user to disable the max-AMSDU bit. */
+	__check_htcap_disable(sdata, ht_cap, IEEE80211_HT_CAP_MAX_AMSDU);
+
+	/* Allow user to decrease AMPDU factor */
+	if (sdata->u.mgd.ht_capa_mask.ampdu_params_info &
+	    IEEE80211_HT_AMPDU_PARM_FACTOR) {
+		u8 n = sdata->u.mgd.ht_capa.ampdu_params_info
+			& IEEE80211_HT_AMPDU_PARM_FACTOR;
+		if (n < ht_cap->ampdu_factor)
+			ht_cap->ampdu_factor = n;
+	}
+
+	/* Allow the user to increase AMPDU density. */
+	if (sdata->u.mgd.ht_capa_mask.ampdu_params_info &
+	    IEEE80211_HT_AMPDU_PARM_DENSITY) {
+		u8 n = (sdata->u.mgd.ht_capa.ampdu_params_info &
+			IEEE80211_HT_AMPDU_PARM_DENSITY)
+			>> IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT;
+		if (n > ht_cap->ampdu_density)
+			ht_cap->ampdu_density = n;
+	}
+}
+
+
+void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
+				       struct ieee80211_supported_band *sband,
 				       struct ieee80211_ht_cap *ht_cap_ie,
 				       struct ieee80211_sta_ht_cap *ht_cap)
 {
@@ -103,6 +178,12 @@ void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
 	/* handle MCS rate 32 too */
 	if (sband->ht_cap.mcs.rx_mask[32/8] & ht_cap_ie->mcs.rx_mask[32/8] & 1)
 		ht_cap->mcs.rx_mask[32/8] |= 1;
+
+	/*
+	 * If user has specified capability over-rides, take care
+	 * of that here.
+	 */
+	ieee80211_apply_htcap_overrides(sdata, ht_cap);
 }
 
 void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 068cc92..2ecaf2d 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -448,6 +448,9 @@ struct ieee80211_if_managed {
 	 */
 	int rssi_min_thold, rssi_max_thold;
 	int last_ave_beacon_signal;
+
+	struct ieee80211_ht_cap ht_capa; /* configured ht-cap over-rides */
+	struct ieee80211_ht_cap ht_capa_mask; /* Valid parts of ht_capa */
 };
 
 struct ieee80211_if_ibss {
@@ -1188,7 +1191,11 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
 				       struct net_device *dev);
 
 /* HT */
-void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
+bool ieee80111_cfg_override_disables_ht40(struct ieee80211_sub_if_data *sdata);
+void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
+				     struct ieee80211_sta_ht_cap *ht_cap);
+void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
+				       struct ieee80211_supported_band *sband,
 				       struct ieee80211_ht_cap *ht_cap_ie,
 				       struct ieee80211_sta_ht_cap *ht_cap);
 void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
@@ -1343,7 +1350,7 @@ void ieee80211_recalc_smps(struct ieee80211_local *local);
 size_t ieee80211_ie_split(const u8 *ies, size_t ielen,
 			  const u8 *ids, int n_ids, size_t offset);
 size_t ieee80211_ie_split_vendor(const u8 *ies, size_t ielen, size_t offset);
-u8 *ieee80211_ie_build_ht_cap(u8 *pos, struct ieee80211_supported_band *sband,
+u8 *ieee80211_ie_build_ht_cap(u8 *pos, struct ieee80211_sta_ht_cap *ht_cap,
 			      u16 cap);
 u8 *ieee80211_ie_build_ht_info(u8 *pos,
 				struct ieee80211_sta_ht_cap *ht_cap,
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index e323d4e..e610103 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -558,6 +558,19 @@ ieee80211_default_mgmt_stypes[NUM_NL80211_IFTYPES] = {
 	},
 };
 
+static const struct ieee80211_ht_cap mac80211_ht_capa_mod_mask = {
+	.ampdu_params_info = IEEE80211_HT_AMPDU_PARM_FACTOR |
+			     IEEE80211_HT_AMPDU_PARM_DENSITY,
+
+	.cap_info = cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
+				IEEE80211_HT_CAP_MAX_AMSDU |
+				IEEE80211_HT_CAP_SGI_40),
+	.mcs = {
+		.rx_mask = { 0xff, 0xff, 0xff, 0xff, 0xff,
+			     0xff, 0xff, 0xff, 0xff, 0xff, },
+	},
+};
+
 struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 					const struct ieee80211_ops *ops)
 {
@@ -629,6 +642,7 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 	local->user_power_level = -1;
 	local->uapsd_queues = IEEE80211_DEFAULT_UAPSD_QUEUES;
 	local->uapsd_max_sp_len = IEEE80211_DEFAULT_MAX_SP_LEN;
+	wiphy->ht_capa_mod_mask = &mac80211_ht_capa_mod_mask;
 
 	INIT_LIST_HEAD(&local->interfaces);
 
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index b3a125f..ee82d2f 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -366,7 +366,7 @@ int mesh_add_ht_cap_ie(struct sk_buff *skb,
 		return -ENOMEM;
 
 	pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
-	ieee80211_ie_build_ht_cap(pos, sband, sband->ht_cap.cap);
+	ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
 
 	return 0;
 }
diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c
index 0140e88..7314372b 100644
--- a/net/mac80211/mesh_plink.c
+++ b/net/mac80211/mesh_plink.c
@@ -101,7 +101,8 @@ static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata,
 	set_sta_flag(sta, WLAN_STA_WME);
 	sta->sta.supp_rates[local->hw.conf.channel->band] = rates;
 	if (elems->ht_cap_elem)
-		ieee80211_ht_cap_ie_to_sta_ht_cap(sband, elems->ht_cap_elem,
+		ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
+						  elems->ht_cap_elem,
 						  &sta->sta.ht_cap);
 	rate_control_rate_init(sta);
 
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 9d1fb85..193cda5 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -209,6 +209,7 @@ static u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata,
 		channel_type = NL80211_CHAN_HT20;
 
 		if (!(ap_ht_cap_flags & IEEE80211_HT_CAP_40MHZ_INTOLERANT) &&
+		    !ieee80111_cfg_override_disables_ht40(sdata) &&
 		    (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) &&
 		    (hti->ht_param & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
 			switch(hti->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
@@ -1120,6 +1121,8 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 
 	/* on the next assoc, re-program HT parameters */
 	sdata->ht_opmode_valid = false;
+	memset(&ifmgd->ht_capa, 0, sizeof(ifmgd->ht_capa));
+	memset(&ifmgd->ht_capa_mask, 0, sizeof(ifmgd->ht_capa_mask));
 
 	local->power_constr_level = 0;
 
@@ -1614,7 +1617,7 @@ static bool ieee80211_assoc_success(struct ieee80211_work *wk,
 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 
 	if (elems.ht_cap_elem && !(ifmgd->flags & IEEE80211_STA_DISABLE_11N))
-		ieee80211_ht_cap_ie_to_sta_ht_cap(sband,
+		ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 				elems.ht_cap_elem, &sta->sta.ht_cap);
 
 	ap_ht_cap_flags = sta->sta.ht_cap.cap;
@@ -1983,7 +1986,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 
 		sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
 
-		ieee80211_ht_cap_ie_to_sta_ht_cap(sband,
+		ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
 				elems.ht_cap_elem, &sta->sta.ht_cap);
 
 		ap_ht_cap_flags = sta->sta.ht_cap.cap;
@@ -2643,6 +2646,13 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
 			ifmgd->flags |= IEEE80211_STA_DISABLE_11N;
 
 
+	if (req->flags & ASSOC_REQ_DISABLE_HT)
+		ifmgd->flags |= IEEE80211_STA_DISABLE_11N;
+
+	memcpy(&ifmgd->ht_capa, &req->ht_capa, sizeof(ifmgd->ht_capa));
+	memcpy(&ifmgd->ht_capa_mask, &req->ht_capa_mask,
+	       sizeof(ifmgd->ht_capa_mask));
+
 	if (req->ie && req->ie_len) {
 		memcpy(wk->ie, req->ie, req->ie_len);
 		wk->ie_len = req->ie_len;
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 3a00814..1c489bb 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -813,7 +813,8 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 	}
 
 	if (sband->ht_cap.ht_supported)
-		pos = ieee80211_ie_build_ht_cap(pos, sband, sband->ht_cap.cap);
+		pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
+						sband->ht_cap.cap);
 
 	/*
 	 * If adding more here, adjust code in main.c
@@ -1356,7 +1357,7 @@ void ieee80211_disable_rssi_reports(struct ieee80211_vif *vif)
 }
 EXPORT_SYMBOL(ieee80211_disable_rssi_reports);
 
-u8 *ieee80211_ie_build_ht_cap(u8 *pos, struct ieee80211_supported_band *sband,
+u8 *ieee80211_ie_build_ht_cap(u8 *pos, struct ieee80211_sta_ht_cap *ht_cap,
 			      u16 cap)
 {
 	__le16 tmp;
@@ -1371,13 +1372,13 @@ u8 *ieee80211_ie_build_ht_cap(u8 *pos, struct ieee80211_supported_band *sband,
 	pos += sizeof(u16);
 
 	/* AMPDU parameters */
-	*pos++ = sband->ht_cap.ampdu_factor |
-		 (sband->ht_cap.ampdu_density <<
+	*pos++ = ht_cap->ampdu_factor |
+		 (ht_cap->ampdu_density <<
 			IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
 
 	/* MCS set */
-	memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
-	pos += sizeof(sband->ht_cap.mcs);
+	memcpy(pos, &ht_cap->mcs, sizeof(ht_cap->mcs));
+	pos += sizeof(ht_cap->mcs);
 
 	/* extended capabilities */
 	pos += sizeof(__le16);
diff --git a/net/mac80211/work.c b/net/mac80211/work.c
index 3dd5a89..6884a2d 100644
--- a/net/mac80211/work.c
+++ b/net/mac80211/work.c
@@ -94,7 +94,8 @@ static int ieee80211_compatible_rates(const u8 *supp_rates, int supp_rates_len,
 
 /* frame sending functions */
 
-static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
+static void ieee80211_add_ht_ie(struct ieee80211_sub_if_data *sdata,
+				struct sk_buff *skb, const u8 *ht_info_ie,
 				struct ieee80211_supported_band *sband,
 				struct ieee80211_channel *channel,
 				enum ieee80211_smps_mode smps)
@@ -102,7 +103,10 @@ static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
 	struct ieee80211_ht_info *ht_info;
 	u8 *pos;
 	u32 flags = channel->flags;
-	u16 cap = sband->ht_cap.cap;
+	u16 cap;
+	struct ieee80211_sta_ht_cap ht_cap;
+
+	BUILD_BUG_ON(sizeof(ht_cap) != sizeof(sband->ht_cap));
 
 	if (!sband->ht_cap.ht_supported)
 		return;
@@ -113,9 +117,13 @@ static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
 	if (ht_info_ie[1] < sizeof(struct ieee80211_ht_info))
 		return;
 
+	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
+	ieee80211_apply_htcap_overrides(sdata, &ht_cap);
+
 	ht_info = (struct ieee80211_ht_info *)(ht_info_ie + 2);
 
 	/* determine capability flags */
+	cap = ht_cap.cap;
 
 	switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
 	case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
@@ -154,7 +162,7 @@ static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
 
 	/* reserve and fill IE */
 	pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
-	ieee80211_ie_build_ht_cap(pos, sband, cap);
+	ieee80211_ie_build_ht_cap(pos, &ht_cap, cap);
 }
 
 static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
@@ -329,7 +337,7 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
 
 	if (wk->assoc.use_11n && wk->assoc.wmm_used &&
 	    local->hw.queues >= 4)
-		ieee80211_add_ht_ie(skb, wk->assoc.ht_information_ie,
+		ieee80211_add_ht_ie(sdata, skb, wk->assoc.ht_information_ie,
 				    sband, wk->chan, wk->assoc.smps);
 
 	/* if present, add any custom non-vendor IEs that go after HT */
-- 
1.7.3.4

Re: [PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[Johannes Berg]

On Fri, 2011-11-18 at 11:32 -0800, greearb@candelatech.com wrote:
> From: Ben Greear <greearb@candelatech.com>
> 
> This implements ht-cap over-rides for mac80211 drivers.
> HT may be disabled, making an /a/b/g/n station act like an
> a/b/g station.  HT40 may be disabled forcing the station to
> be HT20 even if the AP and local hardware support HT40.
> 
> MAX-AMSDU may be disabled.
> AMPDU-Density may be increased.
> AMPDU-Factor may be decreased.
> 
> This has been successfully tested with ath9k using patched
> wpa_supplicant and iw.
> 
> Signed-off-by: Ben Greear <greearb@candelatech.com>
> ---
> 
> v10:
>  *  Add check in ieee80211_apply_htcap_overrides to make
>     sure we are type NL80211_IFTYPE_STATION.
> 
>  *  Memset u.mgd.ht_capa and ht_capa_mask to 0 in
>     ieee80211_set_disassoc to make sure we do not try to
>     use stale data.
> 
>  *  Add cpu_to_le16 when dealing with u.mgd.ht_capa*
>     Appears to make no change on x86, but should help
>     with certain other platforms.
> 
>  *  Addressed other issues brought up in review of v9.

Thanks. I haven't tested it, but see no obvious bugs. :-)

johannes

Re: [PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[Ben Greear]

On 11/18/2011 12:30 PM, Johannes Berg wrote:
> On Fri, 2011-11-18 at 11:32 -0800, greearb@candelatech.com wrote:
>> From: Ben Greear<greearb@candelatech.com>
>>
>> This implements ht-cap over-rides for mac80211 drivers.
>> HT may be disabled, making an /a/b/g/n station act like an
>> a/b/g station.  HT40 may be disabled forcing the station to
>> be HT20 even if the AP and local hardware support HT40.
>>
>> MAX-AMSDU may be disabled.
>> AMPDU-Density may be increased.
>> AMPDU-Factor may be decreased.
>>
>> This has been successfully tested with ath9k using patched
>> wpa_supplicant and iw.
>>
>> Signed-off-by: Ben Greear<greearb@candelatech.com>
>> ---
>>
>> v10:
>>   *  Add check in ieee80211_apply_htcap_overrides to make
>>      sure we are type NL80211_IFTYPE_STATION.
>>
>>   *  Memset u.mgd.ht_capa and ht_capa_mask to 0 in
>>      ieee80211_set_disassoc to make sure we do not try to
>>      use stale data.
>>
>>   *  Add cpu_to_le16 when dealing with u.mgd.ht_capa*
>>      Appears to make no change on x86, but should help
>>      with certain other platforms.
>>
>>   *  Addressed other issues brought up in review of v9.
>
> Thanks. I haven't tested it, but see no obvious bugs. :-)

Well, feels like progress!

If you actually want to enable/view the new features, you'll want
to patch hostap and iw.  You could use my trees if you want, though
they have some extra stuff and the ht-caps logic needs the cpu_to_le16
changes and probably a bit of other cleanup at the moment.

https://github.com/greearb/hostap-ct
https://github.com/greearb/iw-ct

I'll post some clean iw and hostap patches later today if all goes well.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com

Re: [PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[Johannes Berg]

Please fix:

net/mac80211/ht.c:31:6: warning: symbol '__check_htcap_disable' was not
declared. Should it be static?

johannes

Re: [PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[Ben Greear]

On 11/24/2011 05:49 AM, Johannes Berg wrote:
> Please fix:
>
> net/mac80211/ht.c:31:6: warning: symbol '__check_htcap_disable' was not
> declared. Should it be static?

I sent a patch to make this static, but I do not see the warning.  Are you
running something other than a standard 'make bzImage modules' to
see this warning?

Thanks,
Ben

>
> johannes


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com

Re: [PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[Johannes Berg]

On Thu, 2011-11-24 at 11:16 -0800, Ben Greear wrote:
> On 11/24/2011 05:49 AM, Johannes Berg wrote:
> > Please fix:
> >
> > net/mac80211/ht.c:31:6: warning: symbol '__check_htcap_disable' was not
> > declared. Should it be static?
> 
> I sent a patch to make this static, but I do not see the warning.  Are you
> running something other than a standard 'make bzImage modules' to
> see this warning?

Yes, this is a sparse warning, make C=1 or C=2

johannes

Re: [PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[Arend van Spriel]

On 11/24/2011 08:16 PM, Ben Greear wrote:
> On 11/24/2011 05:49 AM, Johannes Berg wrote:
>> Please fix:
>>
>> net/mac80211/ht.c:31:6: warning: symbol '__check_htcap_disable' was not
>> declared. Should it be static?
> 
> I sent a patch to make this static, but I do not see the warning.  Are you
> running something other than a standard 'make bzImage modules' to
> see this warning?
> 
> Thanks,
> Ben
> 

This is probably a sparse warning so you need to add C=2 on the command
line.

Gr. AvS

Re: [PATCH v10 2/2] mac80211: Support ht-cap over-rides.

[Ben Greear]

On 12/03/2011 08:36 AM, Christian Lamparter wrote:
> On Friday 18 November 2011 20:32:00 greearb@candelatech.com wrote:

Thanks for the bug report.  I'll try to get a fix for this later
today.

Thanks,
Ben


> WARNING: at net/mac80211/ht.c:50 ieee80211_apply_htcap_overrides+0x28/0xeb [mac80211]()
>
> Pid: 2912, comm: hostapd Not tainted #4
>
> Call Trace:
>
> [<ffffffff8102f957>] ? warn_slowpath_common+0x78/0x8c
>
> [<ffffffffa0305671>] ? ieee80211_apply_htcap_overrides+0x28/0xeb [mac80211]
>
> [<ffffffffa031188c>] ? sta_apply_parameters+0x1c7/0x24d [mac80211]
>
> [<ffffffffa0312bcb>] ? ieee80211_add_station+0xf5/0x14c [mac80211]
>
> [<ffffffffa005532e>] ? nl80211_new_station+0x201/0x227 [cfg80211]
>
> [<ffffffffa0052d0b>] ? nl80211_pre_doit+0x8f/0x10b [cfg80211]
>
> [<ffffffff813ab02f>] ? genl_rcv_msg+0x1c2/0x1fa
>
> [...]
>
> ---[ end trace 222d1b5c0c3ca878 ]---
>
>
> I think the WARN_ON_ONCE has to go to a different place. it triggers in AP mode.
>
> [And no, I didn't do any overrides at all, it's just that ieee80211_add_station
>
> calls sta_apply_parameters which in turn calls ieee80211_apply_htcap_overrides
>
> and so on]
>
>
> Regards,
>
> Chr
>


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com