[PATCH v9 0/4] Multiple BSSID support

[PATCH v9 0/4] Multiple BSSID support

[Aloka Dixit]

This patchset adds support for multiple BSSID and
enhanced multi-BSSID advertisements.

This version modifies only nl80211 patch (1/4) which describes
the difference.

John Crispin (4):
  nl80211: add basic multiple bssid support
  mac80211: add multiple bssid support to interface handling
  mac80211: add multiple bssid/EMA support to beacon handling
  mac80211: CSA on non-transmitting interfaces

 include/net/cfg80211.h       |  47 ++++++
 include/net/mac80211.h       | 116 ++++++++++++++-
 include/uapi/linux/nl80211.h |  84 +++++++++++
 net/mac80211/cfg.c           | 178 ++++++++++++++++++++--
 net/mac80211/debugfs.c       |   1 +
 net/mac80211/ieee80211_i.h   |   2 +
 net/mac80211/iface.c         |   6 +
 net/mac80211/tx.c            | 189 ++++++++++++++++++++---
 net/wireless/nl80211.c       | 280 ++++++++++++++++++++++++++++++-----
 9 files changed, 830 insertions(+), 73 deletions(-)


base-commit: 38b5133ad607ecdcc8d24906d1ac9cc8df41acd5
-- 
2.25.0

[PATCH v9 1/4] nl80211: add basic multiple bssid support

[Aloka Dixit]

From: John Crispin <john@phrozen.org>

This patch adds support for passing the multiple bssid config to the
kernel when an AP gets started. If the BSS is non-transmitting we need
to pass

* the ifidx of the transmitting parent
* the BSS index in the set
* the BSS count of the set
* flag indicating if we want to do EMA
* the multiple bssid elements as an array inside the beacon data

This allows use to generate multiple bssid beacons as well as EMA ones.

Signed-off-by: John Crispin <john@phrozen.org>
Co-developed-by: Aloka Dixit <alokad@codeaurora.org>
Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v9: Added check around kfree(params.acl)
    Corrected comment descriptions for NL80211_EXT_FEATURE_MULTIPLE_BSSID_AP
	and max_profile_periodicity

v8: Addition of NL80211_EXT_FEATURE_MULTIPLE_BSSID_AP,
    NL80211_EXT_FEATURE_EMA_AP and wiphy parameters max_num_vaps,
	max_profile_periodicity exposed to the application.

 include/net/cfg80211.h       |  47 ++++++
 include/uapi/linux/nl80211.h |  84 +++++++++++
 net/wireless/nl80211.c       | 280 ++++++++++++++++++++++++++++++-----
 3 files changed, 371 insertions(+), 40 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 911fae42b0c0..7755a04a6de6 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -485,6 +485,21 @@ struct ieee80211_supported_band {
 	const struct ieee80211_sband_iftype_data *iftype_data;
 };
 
+/**
+ * struct cfg80211_multiple_bssid - AP settings for multi bssid
+ *
+ * @index: the index of this AP in the multi bssid group.
+ * @count: the total number of multi bssid peer APs.
+ * @parent: non-transmitted BSSs transmitted parents index
+ * @ema: Shall the beacons be sent out in EMA mode.
+ */
+struct cfg80211_multiple_bssid {
+	u8 index;
+	u8 count;
+	u32 parent;
+	bool ema;
+};
+
 /**
  * ieee80211_get_sband_iftype_data - return sband data for a given iftype
  * @sband: the sband to search for the STA on
@@ -1032,6 +1047,23 @@ struct cfg80211_crypto_settings {
 	enum nl80211_sae_pwe_mechanism sae_pwe;
 };
 
+/**
+ * struct cfg80211_multiple_bssid_data - Multiple BSSID elements
+ *
+ * @cnt: Number of elements in array %elems.
+ *
+ * @elems: Array of multiple BSSID element(s) to be added into Beacon frames.
+ * @elems.data: Data for multiple BSSID elements.
+ * @elems.len: Length of data.
+ */
+struct cfg80211_multiple_bssid_data {
+	u8 cnt;
+	struct {
+		u8 *data;
+		size_t len;
+	} elems[];
+};
+
 /**
  * struct cfg80211_beacon_data - beacon data
  * @head: head portion of beacon (before TIM IE)
@@ -1058,6 +1090,7 @@ struct cfg80211_crypto_settings {
  *	Token (measurement type 11)
  * @lci_len: LCI data length
  * @civicloc_len: Civic location data length
+ * @multiple_bssid: multiple_bssid elements
  */
 struct cfg80211_beacon_data {
 	const u8 *head, *tail;
@@ -1076,6 +1109,8 @@ struct cfg80211_beacon_data {
 	size_t probe_resp_len;
 	size_t lci_len;
 	size_t civicloc_len;
+
+	struct cfg80211_multiple_bssid_data *multiple_bssid;
 };
 
 struct mac_address {
@@ -1181,6 +1216,7 @@ enum cfg80211_ap_settings_flags {
  * @he_oper: HE operation IE (or %NULL if HE isn't enabled)
  * @fils_discovery: FILS discovery transmission parameters
  * @unsol_bcast_probe_resp: Unsolicited broadcast probe response parameters
+ * @multiple_bssid: AP settings for multiple bssid.
  */
 struct cfg80211_ap_settings {
 	struct cfg80211_chan_def chandef;
@@ -1213,6 +1249,7 @@ struct cfg80211_ap_settings {
 	struct cfg80211_he_bss_color he_bss_color;
 	struct cfg80211_fils_discovery fils_discovery;
 	struct cfg80211_unsol_bcast_probe_resp unsol_bcast_probe_resp;
+	struct cfg80211_multiple_bssid multiple_bssid;
 };
 
 /**
@@ -4941,6 +4978,11 @@ struct wiphy_iftype_akm_suites {
  *	configuration through the %NL80211_TID_CONFIG_ATTR_RETRY_SHORT and
  *	%NL80211_TID_CONFIG_ATTR_RETRY_LONG attributes
  * @sar_capa: SAR control capabilities
+ *
+ * @multiple_bssid: Describes device's multiple BSSID config support
+ * @multiple_bssid.max_num_vaps: Maximum number of VAPS supported by the driver
+ * @multiple_bssid.max_profile_periodicity: Maximum EMA profile periodicity
+ *	supported by the driver
  */
 struct wiphy {
 	struct mutex mtx;
@@ -5083,6 +5125,11 @@ struct wiphy {
 
 	const struct cfg80211_sar_capa *sar_capa;
 
+	struct {
+		u8 max_num_vaps;
+		u8 max_profile_periodicity;
+	} multiple_bssid;
+
 	char priv[] __aligned(NETDEV_ALIGN);
 };
 
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index ac78da99fccd..740bae5369ac 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2557,6 +2557,19 @@ enum nl80211_commands {
  *	disassoc events to indicate that an immediate reconnect to the AP
  *	is desired.
  *
+ * @NL80211_ATTR_MULTIPLE_BSSID_CONFIG: Optional parameter to configure
+ *	multiple BSSID and enhanced multi-BSSID advertisements.
+ *	This attribute is also used to advertise the maximum number of VAPs
+ *	supported by the driver to the application. It is a nested attribute,
+ *	see &enum nl80211_multiple_bssid_config_attributes.
+ *
+ * @NL80211_ATTR_MULTIPLE_BSSID_ELEMS: Optional parameter for multiple BSSID
+ *	elements data. This attribute is also used to advertise the maximum
+ *	profile periodicity supported by the driver to the application, if
+ *	enhanced multi-BSS advertisements (EMA) feature is enabled.
+ *	It is a nested attribute, see
+ *	&enum nl80211_multiple_bssid_elems_attributes.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3054,6 +3067,9 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_DISABLE_HE,
 
+	NL80211_ATTR_MULTIPLE_BSSID_CONFIG,
+	NL80211_ATTR_MULTIPLE_BSSID_ELEMS,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -5937,6 +5953,11 @@ enum nl80211_feature_flags {
  * @NL80211_EXT_FEATURE_BEACON_RATE_HE: Driver supports beacon rate
  *	configuration (AP/mesh) with HE rates.
  *
+ * @NL80211_EXT_FEATURE_MULTIPLE_BSSID_AP: Driver/device supports multiple
+ *	BSSID advertisements.
+ * @NL80211_EXT_FEATURE_EMA_AP: Driver/device supports enhanced multiple BSSID
+ *	advertisements (EMA).
+ *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
  */
@@ -5998,6 +6019,8 @@ enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_FILS_DISCOVERY,
 	NL80211_EXT_FEATURE_UNSOL_BCAST_PROBE_RESP,
 	NL80211_EXT_FEATURE_BEACON_RATE_HE,
+	NL80211_EXT_FEATURE_MULTIPLE_BSSID_AP,
+	NL80211_EXT_FEATURE_EMA_AP,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,
@@ -7277,4 +7300,65 @@ enum nl80211_sar_specs_attrs {
 	NL80211_SAR_ATTR_SPECS_MAX = __NL80211_SAR_ATTR_SPECS_LAST - 1,
 };
 
+/**
+ * enum nl80211_multiple_bssid_config_attributes - Attributes to configure
+ *	multiple BSSID and enhanced multi-BSSID advertisements.
+ *
+ * @__NL80211_MULTIPLE_BSSID_CONFIG_ATTR_INVALID: Invalid
+ *
+ * @NL80211_MULTIPLE_BSSID_CONFIG_ATTR_PARENT: For a non-transmitted BSSID, this
+ *	attribute provides the interface index (u32) of the transmitted profile
+ *	in the multiple BSSID set.
+ *
+ * @NL80211_MULTIPLE_BSSID_CONFIG_ATTR_INDEX: The index of this BSS (u8) inside
+ *	multiple BSSID set.
+ *
+ * @NL80211_MULTIPLE_BSSID_CONFIG_ATTR_COUNT: Total number of BSSs (u8) in the
+ *	multiple BSSID set.
+ *
+ * @NL80211_MULTIPLE_BSSID_CONFIG_ATTR_EMA: Flag to indicate if enhanced multi-BSSID
+ *	advertisements (EMA) feature is enabled.
+ *	If set to 1, elements provided through attribute
+ *	%NL80211_ATTR_MULTIPLE_BSSID_ELEMS are split into multiple beacons.
+ *	Otherwise, all elements will be included in every beacon.
+ *
+ * @__NL80211_MULTIPLE_BSSID_CONFIG_ATTR_LAST: Internal
+ * @NL80211_MULTIPLE_BSSID_CONFIG_ATTR_MAX: highest attribute
+ */
+enum nl80211_multiple_bssid_config_attributes {
+	__NL80211_MULTIPLE_BSSID_CONFIG_ATTR_INVALID,
+
+	NL80211_MULTIPLE_BSSID_CONFIG_ATTR_PARENT,
+	NL80211_MULTIPLE_BSSID_CONFIG_ATTR_INDEX,
+	NL80211_MULTIPLE_BSSID_CONFIG_ATTR_COUNT,
+	NL80211_MULTIPLE_BSSID_CONFIG_ATTR_EMA,
+
+	/* keep last */
+	__NL80211_MULTIPLE_BSSID_CONFIG_ATTR_LAST,
+	NL80211_MULTIPLE_BSSID_CONFIG_ATTR_MAX =
+		__NL80211_MULTIPLE_BSSID_CONFIG_ATTR_LAST - 1,
+};
+
+/**
+ * enum nl80211_multiple_bssid_elems_attributes - Attributes used to pass
+ *	multiple BSSID elements data.
+ *
+ * @__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_INVALID: Invalid
+ *
+ * @NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT: Number of multiple BSSID
+ *	elements (u8).
+ *
+ * @NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA: Array of multiple BSSID elements.
+ */
+enum nl80211_multiple_bssid_elems_attributes {
+	__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_INVALID,
+
+	NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT,
+	NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA,
+
+	__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_LAST,
+	NL80211_MULTIPLE_BSSID_ELEMS_ATTR_MAX =
+		__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_LAST - 1,
+};
+
 #endif /* __LINUX_NL80211_H */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 521d36bb0803..9ff33fc3967d 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -431,6 +431,20 @@ sar_policy[NL80211_SAR_ATTR_MAX + 1] = {
 	[NL80211_SAR_ATTR_SPECS] = NLA_POLICY_NESTED_ARRAY(sar_specs_policy),
 };
 
+static const struct nla_policy
+nl80211_multiple_bssid_elems_policy[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_MAX + 1] = {
+	[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT] = { .type = NLA_U8 },
+	[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA] = { .type = NLA_NESTED },
+};
+
+static const struct nla_policy
+nl80211_multiple_bssid_policy[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_MAX + 1] = {
+	[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_PARENT] = { .type = NLA_U32 },
+	[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_INDEX] = { .type = NLA_U8 },
+	[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_COUNT] = { .type = NLA_U8 },
+	[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_EMA] = { .type = NLA_FLAG },
+};
+
 static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[0] = { .strict_start_type = NL80211_ATTR_HE_OBSS_PD },
 	[NL80211_ATTR_WIPHY] = { .type = NLA_U32 },
@@ -753,6 +767,10 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_RECONNECT_REQUESTED] = { .type = NLA_REJECT },
 	[NL80211_ATTR_SAR_SPEC] = NLA_POLICY_NESTED(sar_policy),
 	[NL80211_ATTR_DISABLE_HE] = { .type = NLA_FLAG },
+	[NL80211_ATTR_MULTIPLE_BSSID_CONFIG] =
+			NLA_POLICY_NESTED(nl80211_multiple_bssid_policy),
+	[NL80211_ATTR_MULTIPLE_BSSID_ELEMS] =
+			NLA_POLICY_NESTED(nl80211_multiple_bssid_elems_policy),
 };
 
 /* policy for the key attributes */
@@ -2192,6 +2210,49 @@ nl80211_put_sar_specs(struct cfg80211_registered_device *rdev,
 	return -ENOBUFS;
 }
 
+static int
+nl80211_put_multiple_bssid_support(struct wiphy *wiphy, struct sk_buff *msg)
+{
+	struct nlattr *config = NULL, *elems = NULL;
+
+	if (!wiphy_ext_feature_isset(wiphy,
+				     NL80211_EXT_FEATURE_MULTIPLE_BSSID_AP))
+		return 0;
+
+	if (wiphy->multiple_bssid.max_num_vaps) {
+		config = nla_nest_start(msg,
+					NL80211_ATTR_MULTIPLE_BSSID_CONFIG);
+		if (!config)
+			return -ENOSPC;
+
+		if (nla_put_u8(msg, NL80211_MULTIPLE_BSSID_CONFIG_ATTR_COUNT,
+			       wiphy->multiple_bssid.max_num_vaps))
+			goto fail_config;
+
+		nla_nest_end(msg, config);
+	}
+
+	if (wiphy_ext_feature_isset(wiphy, NL80211_EXT_FEATURE_EMA_AP) &&
+	    wiphy->multiple_bssid.max_profile_periodicity) {
+		elems = nla_nest_start(msg, NL80211_ATTR_MULTIPLE_BSSID_ELEMS);
+		if (!elems)
+			goto fail_config;
+
+		if (nla_put_u8(msg, NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT,
+			       wiphy->multiple_bssid.max_profile_periodicity))
+			goto fail_elems;
+
+		nla_nest_end(msg, elems);
+	}
+	return 0;
+
+fail_elems:
+	nla_nest_cancel(msg, elems);
+fail_config:
+	nla_nest_cancel(msg, config);
+	return -ENOBUFS;
+}
+
 struct nl80211_dump_wiphy_state {
 	s64 filter_wiphy;
 	long start;
@@ -2774,6 +2835,9 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
 		if (nl80211_put_sar_specs(rdev, msg))
 			goto nla_put_failure;
 
+		if (nl80211_put_multiple_bssid_support(&rdev->wiphy, msg))
+			goto nla_put_failure;
+
 		/* done */
 		state->split_start = 0;
 		break;
@@ -4952,6 +5016,90 @@ static int validate_beacon_tx_rate(struct cfg80211_registered_device *rdev,
 	return 0;
 }
 
+static int
+nl80211_parse_multiple_bssid_config(struct wiphy *wiphy,
+				    struct nlattr *attrs,
+				    struct cfg80211_ap_settings *params)
+{
+	struct nlattr *tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_MAX + 1];
+	int ret;
+	struct cfg80211_multiple_bssid *config = &params->multiple_bssid;
+
+	if (!wiphy_ext_feature_isset(wiphy,
+				     NL80211_EXT_FEATURE_MULTIPLE_BSSID_AP))
+		return -EINVAL;
+
+	ret = nla_parse_nested(tb, NL80211_MULTIPLE_BSSID_CONFIG_ATTR_MAX, attrs, NULL,
+			       NULL);
+	if (ret)
+		return ret;
+
+	config->ema = nla_get_flag(tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_EMA]);
+	if (config->ema &&
+	    (!wiphy_ext_feature_isset(wiphy,
+				      NL80211_EXT_FEATURE_EMA_AP) ||
+	     (wiphy->multiple_bssid.max_profile_periodicity &&
+	      params->beacon.multiple_bssid->cnt >
+	      wiphy->multiple_bssid.max_profile_periodicity)))
+		return -EINVAL;
+
+	if (!tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_COUNT])
+		return -EINVAL;
+
+	config->count = nla_get_u8(tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_COUNT]);
+	if (config->count < 1 ||
+	    (wiphy->multiple_bssid.max_num_vaps &&
+	     config->count > wiphy->multiple_bssid.max_num_vaps))
+		return -EINVAL;
+
+	if (tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_PARENT])
+		config->parent = nla_get_u32(tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_PARENT]);
+
+	if (tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_INDEX])
+		config->index = nla_get_u8(tb[NL80211_MULTIPLE_BSSID_CONFIG_ATTR_INDEX]);
+
+	return 0;
+}
+
+static struct cfg80211_multiple_bssid_data *
+nl80211_parse_multiple_bssid_elems(struct wiphy *wiphy, struct nlattr *attrs)
+{
+	struct cfg80211_multiple_bssid_data *multiple_bssid;
+	struct nlattr *nl_ie;
+	struct nlattr *tb[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_MAX + 1];
+	int rem_ie;
+	u8 i = 0, err, num_elems;
+
+	if (!wiphy_ext_feature_isset(wiphy,
+				     NL80211_EXT_FEATURE_MULTIPLE_BSSID_AP))
+		return NULL;
+
+	err = nla_parse_nested(tb, NL80211_MULTIPLE_BSSID_ELEMS_ATTR_MAX,
+			       attrs, NULL, NULL);
+	if (err)
+		return NULL;
+
+	if (!tb[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT] ||
+	    !tb[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA])
+		return NULL;
+
+	num_elems = nla_get_u8(tb[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT]);
+	multiple_bssid = kzalloc(struct_size(multiple_bssid, elems, num_elems),
+				 GFP_KERNEL);
+	if (!multiple_bssid)
+		return NULL;
+
+	multiple_bssid->cnt = num_elems;
+	nla_for_each_nested(nl_ie, tb[NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA],
+			    rem_ie) {
+		multiple_bssid->elems[i].data = nla_data(nl_ie);
+		multiple_bssid->elems[i].len = nla_len(nl_ie);
+		i++;
+	}
+
+	return multiple_bssid;
+}
+
 static int nl80211_parse_beacon(struct cfg80211_registered_device *rdev,
 				struct nlattr *attrs[],
 				struct cfg80211_beacon_data *bcn)
@@ -5032,6 +5180,14 @@ static int nl80211_parse_beacon(struct cfg80211_registered_device *rdev,
 		bcn->ftm_responder = -1;
 	}
 
+	if (attrs[NL80211_ATTR_MULTIPLE_BSSID_ELEMS]) {
+		bcn->multiple_bssid = nl80211_parse_multiple_bssid_elems(
+				&rdev->wiphy,
+				attrs[NL80211_ATTR_MULTIPLE_BSSID_ELEMS]);
+		if (!bcn->multiple_bssid)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 
@@ -5317,7 +5473,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 
 	err = nl80211_parse_beacon(rdev, info->attrs, &params.beacon);
 	if (err)
-		return err;
+		goto out;
 
 	params.beacon_interval =
 		nla_get_u32(info->attrs[NL80211_ATTR_BEACON_INTERVAL]);
@@ -5327,7 +5483,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	err = cfg80211_validate_beacon_int(rdev, dev->ieee80211_ptr->iftype,
 					   params.beacon_interval);
 	if (err)
-		return err;
+		goto out;
 
 	/*
 	 * In theory, some of these attributes should be required here
@@ -5340,8 +5496,10 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 		params.ssid = nla_data(info->attrs[NL80211_ATTR_SSID]);
 		params.ssid_len =
 			nla_len(info->attrs[NL80211_ATTR_SSID]);
-		if (params.ssid_len == 0)
-			return -EINVAL;
+		if (params.ssid_len == 0) {
+			err = -EINVAL;
+			goto out;
+		}
 	}
 
 	if (info->attrs[NL80211_ATTR_HIDDEN_SSID])
@@ -5354,57 +5512,74 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 		params.auth_type = nla_get_u32(
 			info->attrs[NL80211_ATTR_AUTH_TYPE]);
 		if (!nl80211_valid_auth_type(rdev, params.auth_type,
-					     NL80211_CMD_START_AP))
-			return -EINVAL;
+					     NL80211_CMD_START_AP)) {
+			err = -EINVAL;
+			goto out;
+		}
 	} else
 		params.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
 
 	err = nl80211_crypto_settings(rdev, info, &params.crypto,
 				      NL80211_MAX_NR_CIPHER_SUITES);
 	if (err)
-		return err;
+		goto out;
 
 	if (info->attrs[NL80211_ATTR_INACTIVITY_TIMEOUT]) {
-		if (!(rdev->wiphy.features & NL80211_FEATURE_INACTIVITY_TIMER))
-			return -EOPNOTSUPP;
+		if (!(rdev->wiphy.features &
+		      NL80211_FEATURE_INACTIVITY_TIMER)) {
+			err = -EOPNOTSUPP;
+			goto out;
+		}
 		params.inactivity_timeout = nla_get_u16(
 			info->attrs[NL80211_ATTR_INACTIVITY_TIMEOUT]);
 	}
 
 	if (info->attrs[NL80211_ATTR_P2P_CTWINDOW]) {
-		if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
-			return -EINVAL;
+		if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) {
+			err = -EINVAL;
+			goto out;
+		}
 		params.p2p_ctwindow =
 			nla_get_u8(info->attrs[NL80211_ATTR_P2P_CTWINDOW]);
 		if (params.p2p_ctwindow != 0 &&
-		    !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_CTWIN))
-			return -EINVAL;
+		    !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_CTWIN)) {
+			err = -EINVAL;
+			goto out;
+		}
 	}
 
 	if (info->attrs[NL80211_ATTR_P2P_OPPPS]) {
 		u8 tmp;
 
-		if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
-			return -EINVAL;
+		if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) {
+			err = -EINVAL;
+			goto out;
+		}
 		tmp = nla_get_u8(info->attrs[NL80211_ATTR_P2P_OPPPS]);
 		params.p2p_opp_ps = tmp;
 		if (params.p2p_opp_ps != 0 &&
-		    !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_OPPPS))
-			return -EINVAL;
+		    !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_OPPPS)) {
+			err = -EINVAL;
+			goto out;
+		}
 	}
 
 	if (info->attrs[NL80211_ATTR_WIPHY_FREQ]) {
 		err = nl80211_parse_chandef(rdev, info, &params.chandef);
 		if (err)
-			return err;
+			goto out;
 	} else if (wdev->preset_chandef.chan) {
 		params.chandef = wdev->preset_chandef;
-	} else if (!nl80211_get_ap_channel(rdev, &params))
-		return -EINVAL;
+	} else if (!nl80211_get_ap_channel(rdev, &params)) {
+		err = -EINVAL;
+		goto out;
+	}
 
 	if (!cfg80211_reg_can_beacon_relax(&rdev->wiphy, &params.chandef,
-					   wdev->iftype))
-		return -EINVAL;
+					   wdev->iftype)) {
+		err = -EINVAL;
+		goto out;
+	}
 
 	if (info->attrs[NL80211_ATTR_TX_RATES]) {
 		err = nl80211_parse_tx_bitrate_mask(info, info->attrs,
@@ -5412,12 +5587,12 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 						    &params.beacon_rate,
 						    dev, false);
 		if (err)
-			return err;
+			goto out;
 
 		err = validate_beacon_tx_rate(rdev, params.chandef.chan->band,
 					      &params.beacon_rate);
 		if (err)
-			return err;
+			goto out;
 	}
 
 	if (info->attrs[NL80211_ATTR_SMPS_MODE]) {
@@ -5428,29 +5603,38 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 			break;
 		case NL80211_SMPS_STATIC:
 			if (!(rdev->wiphy.features &
-			      NL80211_FEATURE_STATIC_SMPS))
-				return -EINVAL;
+			      NL80211_FEATURE_STATIC_SMPS)) {
+				err = -EINVAL;
+				goto out;
+			}
 			break;
 		case NL80211_SMPS_DYNAMIC:
 			if (!(rdev->wiphy.features &
-			      NL80211_FEATURE_DYNAMIC_SMPS))
-				return -EINVAL;
+			      NL80211_FEATURE_DYNAMIC_SMPS)) {
+				err = -EINVAL;
+				goto out;
+			}
 			break;
 		default:
-			return -EINVAL;
+			err = -EINVAL;
+			goto out;
 		}
 	} else {
 		params.smps_mode = NL80211_SMPS_OFF;
 	}
 
 	params.pbss = nla_get_flag(info->attrs[NL80211_ATTR_PBSS]);
-	if (params.pbss && !rdev->wiphy.bands[NL80211_BAND_60GHZ])
-		return -EOPNOTSUPP;
+	if (params.pbss && !rdev->wiphy.bands[NL80211_BAND_60GHZ]) {
+		err = -EOPNOTSUPP;
+		goto out;
+	}
 
 	if (info->attrs[NL80211_ATTR_ACL_POLICY]) {
 		params.acl = parse_acl_data(&rdev->wiphy, info);
-		if (IS_ERR(params.acl))
-			return PTR_ERR(params.acl);
+		if (IS_ERR(params.acl)) {
+			err = PTR_ERR(params.acl);
+			goto out;
+		}
 	}
 
 	params.twt_responder =
@@ -5485,7 +5669,16 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 			rdev, info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP],
 			&params);
 		if (err)
-			return err;
+			goto out;
+	}
+
+	if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_CONFIG]) {
+		err = nl80211_parse_multiple_bssid_config(
+			&rdev->wiphy,
+			info->attrs[NL80211_ATTR_MULTIPLE_BSSID_CONFIG],
+			&params);
+		if (err)
+			goto out;
 	}
 
 	nl80211_calculate_ap_params(&params);
@@ -5508,8 +5701,9 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	wdev_unlock(wdev);
 
 out:
-	kfree(params.acl);
-
+	if (!IS_ERR(params.acl))
+		kfree(params.acl);
+	kfree(params.beacon.multiple_bssid);
 	return err;
 }
 
@@ -5533,12 +5727,14 @@ static int nl80211_set_beacon(struct sk_buff *skb, struct genl_info *info)
 
 	err = nl80211_parse_beacon(rdev, info->attrs, &params);
 	if (err)
-		return err;
+		goto out;
 
 	wdev_lock(wdev);
 	err = rdev_change_beacon(rdev, dev, &params);
 	wdev_unlock(wdev);
 
+out:
+	kfree(params.multiple_bssid);
 	return err;
 }
 
@@ -9218,12 +9414,14 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 
 	err = nl80211_parse_beacon(rdev, info->attrs, &params.beacon_after);
 	if (err)
-		return err;
+		goto free;
 
 	csa_attrs = kcalloc(NL80211_ATTR_MAX + 1, sizeof(*csa_attrs),
 			    GFP_KERNEL);
-	if (!csa_attrs)
-		return -ENOMEM;
+	if (!csa_attrs) {
+		err = -ENOMEM;
+		goto free;
+	}
 
 	err = nla_parse_nested_deprecated(csa_attrs, NL80211_ATTR_MAX,
 					  info->attrs[NL80211_ATTR_CSA_IES],
@@ -9341,6 +9539,8 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 	wdev_unlock(wdev);
 
 free:
+	kfree(params.beacon_after.multiple_bssid);
+	kfree(params.beacon_csa.multiple_bssid);
 	kfree(csa_attrs);
 	return err;
 }
-- 
2.25.0

Re: [PATCH v9 1/4] nl80211: add basic multiple bssid support

[Johannes Berg]

On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
> 
> +/**
> + * struct cfg80211_multiple_bssid - AP settings for multi bssid
> + *
> + * @index: the index of this AP in the multi bssid group.
> + * @count: the total number of multi bssid peer APs.
> + * @parent: non-transmitted BSSs transmitted parents index
> + * @ema: Shall the beacons be sent out in EMA mode.
> + */
> +struct cfg80211_multiple_bssid {
> +	u8 index;
> +	u8 count;
> +	u32 parent;
> +	bool ema;
> +};

Can reorder this to make it smaller: bool before u32), or even u32
element first.

> +/**
> + * struct cfg80211_multiple_bssid_data - Multiple BSSID elements
> + *
> + * @cnt: Number of elements in array %elems.
> + *
> + * @elems: Array of multiple BSSID element(s) to be added into Beacon frames.
> + * @elems.data: Data for multiple BSSID elements.
> + * @elems.len: Length of data.
> + */
> +struct cfg80211_multiple_bssid_data {
> +	u8 cnt;
> +	struct {
> +		u8 *data;
> +		size_t len;
> +	} elems[];
> +};

Why are the elements separate, rather than a single big buffer with all
elements?


> + * @multiple_bssid.max_num_vaps: Maximum number of VAPS supported by the driver

Please use upstream terminology, we don't use the term "VAP" (and "VAPS"
would be wrong anyway, "VAPs").

I'd probably call this "max_interfaces", maybe we'll extend this to
other things (mesh?) later?
> 
> +/**
> + * enum nl80211_multiple_bssid_elems_attributes - Attributes used to pass
> + *	multiple BSSID elements data.
> + *
> + * @__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_INVALID: Invalid
> + *
> + * @NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT: Number of multiple BSSID
> + *	elements (u8).
> + *
> + * @NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA: Array of multiple BSSID elements.
> + */
> +enum nl80211_multiple_bssid_elems_attributes {
> +	__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_INVALID,
> +
> +	NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT,
> +	NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA,
> 

Can you clarify why this is an array? See also above.


johannes

Re: [PATCH v9 1/4] nl80211: add basic multiple bssid support

[Aloka Dixit]

On 2021-04-08 05:05, Johannes Berg wrote:
> On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
>> 
>> +/**
>> + * struct cfg80211_multiple_bssid - AP settings for multi bssid
>> + *
>> + * @index: the index of this AP in the multi bssid group.
>> + * @count: the total number of multi bssid peer APs.
>> + * @parent: non-transmitted BSSs transmitted parents index
>> + * @ema: Shall the beacons be sent out in EMA mode.
>> + */
>> +struct cfg80211_multiple_bssid {
>> +	u8 index;
>> +	u8 count;
>> +	u32 parent;
>> +	bool ema;
>> +};
> 
> Can reorder this to make it smaller: bool before u32), or even u32
> element first.
> 

Will do.

>> +/**
>> + * struct cfg80211_multiple_bssid_data - Multiple BSSID elements
>> + *
>> + * @cnt: Number of elements in array %elems.
>> + *
>> + * @elems: Array of multiple BSSID element(s) to be added into Beacon 
>> frames.
>> + * @elems.data: Data for multiple BSSID elements.
>> + * @elems.len: Length of data.
>> + */
>> +struct cfg80211_multiple_bssid_data {
>> +	u8 cnt;
>> +	struct {
>> +		u8 *data;
>> +		size_t len;
>> +	} elems[];
>> +};
> 
> Why are the elements separate, rather than a single big buffer with all
> elements?
> 
> 

This is for EMA AP where each element will hold different
non-transmitted profiles. While copying elements in
ieee80211_assign_beacon(), all are copied one by one.
However during beacon generation in __ieee80211_beacon_get(),
only the element at a given index is actually added.
Hence separate elements.

>> + * @multiple_bssid.max_num_vaps: Maximum number of VAPS supported by 
>> the driver
> 
> Please use upstream terminology, we don't use the term "VAP" (and 
> "VAPS"
> would be wrong anyway, "VAPs").
> 
> I'd probably call this "max_interfaces", maybe we'll extend this to
> other things (mesh?) later?
>> 

Will change.

>> +/**
>> + * enum nl80211_multiple_bssid_elems_attributes - Attributes used to 
>> pass
>> + *	multiple BSSID elements data.
>> + *
>> + * @__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_INVALID: Invalid
>> + *
>> + * @NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT: Number of multiple BSSID
>> + *	elements (u8).
>> + *
>> + * @NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA: Array of multiple BSSID 
>> elements.
>> + */
>> +enum nl80211_multiple_bssid_elems_attributes {
>> +	__NL80211_MULTIPLE_BSSID_ELEMS_ATTR_INVALID,
>> +
>> +	NL80211_MULTIPLE_BSSID_ELEMS_ATTR_COUNT,
>> +	NL80211_MULTIPLE_BSSID_ELEMS_ATTR_DATA,
>> 
> 
> Can you clarify why this is an array? See also above.
> 
> 
> johannes

Array to pass separate MBSSID elements for EMA which will
hold different profiles in the same MBSSID set.

[PATCH v9 2/4] mac80211: add multiple bssid support to interface handling

[Aloka Dixit]

From: John Crispin <john@phrozen.org>

Add a new helper ieee80211_set_multiple_bssid_options() takes propagating
the cfg80211 data down the stack.

The patch also makes sure that all members of the bss set will get closed
when either of them is shutdown.

Signed-off-by: John Crispin <john@phrozen.org>
Co-developed-by: Aloka Dixit <alokad@codeaurora.org>
Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
---
 include/net/mac80211.h | 30 +++++++++++++++++++++++-
 net/mac80211/cfg.c     | 53 ++++++++++++++++++++++++++++++++++++++++++
 net/mac80211/debugfs.c |  1 +
 net/mac80211/iface.c   |  6 +++++
 4 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 2d1d629e5d14..b9f51515c2e8 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -631,6 +631,7 @@ struct ieee80211_fils_discovery {
  * @s1g: BSS is S1G BSS (affects Association Request format).
  * @beacon_tx_rate: The configured beacon transmit rate that needs to be passed
  *	to driver when rate control is offloaded to firmware.
+ * @multiple_bssid: the multiple bssid settings of the AP.
  */
 struct ieee80211_bss_conf {
 	const u8 *bssid;
@@ -700,6 +701,7 @@ struct ieee80211_bss_conf {
 	u32 unsol_bcast_probe_resp_interval;
 	bool s1g;
 	struct cfg80211_bitrate_mask beacon_tx_rate;
+	struct cfg80211_multiple_bssid multiple_bssid;
 };
 
 /**
@@ -1663,6 +1665,19 @@ enum ieee80211_offload_flags {
 	IEEE80211_OFFLOAD_DECAP_ENABLED		= BIT(2),
 };
 
+/**
+ * enum ieee80211_vif_multiple_bssid_flags - virtual interface multiple bssid flags
+ *
+ * @IEEE80211_VIF_MBSS_TRANSMITTING: this BSS is transmitting beacons
+ * @IEEE80211_VIF_MBSS_NON_TRANSMITTING: this BSS is not transmitting beacons
+ * @IEEE80211_VIF_MBSS_EMA_BEACON: beacons should be send out in EMA mode
+ */
+enum ieee80211_vif_multiple_bssid_flags {
+	IEEE80211_VIF_MBSS_TRANSMITTING         = BIT(1),
+	IEEE80211_VIF_MBSS_NON_TRANSMITTING     = BIT(2),
+	IEEE80211_VIF_MBSS_EMA_BEACON           = BIT(3),
+};
+
 /**
  * struct ieee80211_vif - per-interface data
  *
@@ -1709,6 +1724,11 @@ enum ieee80211_offload_flags {
  *	protected by fq->lock.
  * @offload_flags: 802.3 -> 802.11 enapsulation offload flags, see
  *	&enum ieee80211_offload_flags.
+ *
+ * @multiple_bssid: Multiple BSSID configurations.
+ * @multiple_bssid.parent: Interface index of the transmitted BSS.
+ * @multiple_bssid.flags: multiple bssid flags, see
+ *	enum ieee80211_vif_multiple_bssid_flags.
  */
 struct ieee80211_vif {
 	enum nl80211_iftype type;
@@ -1737,6 +1757,11 @@ struct ieee80211_vif {
 
 	bool txqs_stopped[IEEE80211_NUM_ACS];
 
+	struct {
+		struct ieee80211_vif *parent;
+		u32 flags;
+	} multiple_bssid;
+
 	/* must be last */
 	u8 drv_priv[] __aligned(sizeof(void *));
 };
@@ -2384,7 +2409,7 @@ struct ieee80211_txq {
  * @IEEE80211_HW_TX_STATUS_NO_AMPDU_LEN: Driver does not report accurate A-MPDU
  *	length in tx status information
  *
- * @IEEE80211_HW_SUPPORTS_MULTI_BSSID: Hardware supports multi BSSID
+ * @IEEE80211_HW_SUPPORTS_MULTI_BSSID: Hardware supports multi BSSID in STA mode
  *
  * @IEEE80211_HW_SUPPORTS_ONLY_HE_MULTI_BSSID: Hardware supports multi BSSID
  *	only for HE APs. Applies if @IEEE80211_HW_SUPPORTS_MULTI_BSSID is set.
@@ -2399,6 +2424,8 @@ struct ieee80211_txq {
  * @IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD: Hardware supports rx decapsulation
  *	offload
  *
+ * @IEEE80211_HW_SUPPORTS_MULTI_BSSID_AP: Hardware supports multi BSSID in
+ *	AP mode
  * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
  */
 enum ieee80211_hw_flags {
@@ -2453,6 +2480,7 @@ enum ieee80211_hw_flags {
 	IEEE80211_HW_AMPDU_KEYBORDER_SUPPORT,
 	IEEE80211_HW_SUPPORTS_TX_ENCAP_OFFLOAD,
 	IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD,
+	IEEE80211_HW_SUPPORTS_MULTI_BSSID_AP,
 
 	/* keep last, obviously */
 	NUM_IEEE80211_HW_FLAGS
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index c4c70e30ad7f..91e659a43f67 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -111,6 +111,39 @@ static int ieee80211_set_mon_options(struct ieee80211_sub_if_data *sdata,
 	return 0;
 }
 
+static void ieee80211_set_multiple_bssid_options(struct ieee80211_sub_if_data *sdata,
+						 struct cfg80211_ap_settings *params)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct wiphy *wiphy = local->hw.wiphy;
+	struct net_device *parent;
+	struct ieee80211_sub_if_data *psdata;
+
+	if (!ieee80211_hw_check(&local->hw, SUPPORTS_MULTI_BSSID_AP))
+		return;
+
+	if (!params->multiple_bssid.count)
+		return;
+
+	if (params->multiple_bssid.parent) {
+		parent = __dev_get_by_index(wiphy_net(wiphy),
+					    params->multiple_bssid.parent);
+		if (!parent || !parent->ieee80211_ptr)
+			return;
+		psdata = IEEE80211_WDEV_TO_SUB_IF(parent->ieee80211_ptr);
+		if (psdata->vif.multiple_bssid.parent)
+			return;
+		sdata->vif.multiple_bssid.parent = &psdata->vif;
+		sdata->vif.multiple_bssid.flags |= IEEE80211_VIF_MBSS_NON_TRANSMITTING;
+	} else {
+		sdata->vif.multiple_bssid.flags |= IEEE80211_VIF_MBSS_TRANSMITTING;
+	}
+
+	if (params->multiple_bssid.ema)
+		sdata->vif.multiple_bssid.flags |= IEEE80211_VIF_MBSS_EMA_BEACON;
+	sdata->vif.bss_conf.multiple_bssid = params->multiple_bssid;
+}
+
 static struct wireless_dev *ieee80211_add_iface(struct wiphy *wiphy,
 						const char *name,
 						unsigned char name_assign_type,
@@ -141,6 +174,23 @@ static struct wireless_dev *ieee80211_add_iface(struct wiphy *wiphy,
 
 static int ieee80211_del_iface(struct wiphy *wiphy, struct wireless_dev *wdev)
 {
+	struct ieee80211_sub_if_data *sdata;
+
+	sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
+	if (sdata && sdata->vif.type == NL80211_IFTYPE_AP) {
+		if (sdata->vif.multiple_bssid.flags & IEEE80211_VIF_MBSS_TRANSMITTING) {
+			struct ieee80211_sub_if_data *child;
+
+			rcu_read_lock();
+			list_for_each_entry_rcu(child, &sdata->local->interfaces, list)
+				if (child->vif.multiple_bssid.parent == &sdata->vif)
+					dev_close(child->wdev.netdev);
+			rcu_read_unlock();
+		} else {
+			sdata->vif.multiple_bssid.parent = NULL;
+		}
+	}
+
 	ieee80211_if_remove(IEEE80211_WDEV_TO_SUB_IF(wdev));
 
 	return 0;
@@ -1078,6 +1128,9 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 			changed |= BSS_CHANGED_HE_BSS_COLOR;
 	}
 
+	if (sdata->vif.type == NL80211_IFTYPE_AP)
+		ieee80211_set_multiple_bssid_options(sdata, params);
+
 	mutex_lock(&local->mtx);
 	err = ieee80211_vif_use_channel(sdata, &params->chandef,
 					IEEE80211_CHANCTX_SHARED);
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 5296898875ff..249b8f4e6a54 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -456,6 +456,7 @@ static const char *hw_flag_names[] = {
 	FLAG(AMPDU_KEYBORDER_SUPPORT),
 	FLAG(SUPPORTS_TX_ENCAP_OFFLOAD),
 	FLAG(SUPPORTS_RX_DECAP_OFFLOAD),
+	FLAG(SUPPORTS_MULTI_BSSID_AP),
 #undef FLAG
 };
 
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index b80c9b016b2b..6bb48bf87aca 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -376,6 +376,12 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata, bool going_do
 	bool cancel_scan;
 	struct cfg80211_nan_func *func;
 
+	/* make sure the parent is already down */
+	if (sdata->vif.type == NL80211_IFTYPE_AP &&
+	    sdata->vif.multiple_bssid.parent &&
+	    ieee80211_sdata_running(vif_to_sdata(sdata->vif.multiple_bssid.parent)))
+		dev_close(vif_to_sdata(sdata->vif.multiple_bssid.parent)->wdev.netdev);
+
 	clear_bit(SDATA_STATE_RUNNING, &sdata->state);
 
 	cancel_scan = rcu_access_pointer(local->scan_sdata) == sdata;
-- 
2.25.0

Re: [PATCH v9 2/4] mac80211: add multiple bssid support to interface handling

[Johannes Berg]

On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
> From: John Crispin <john@phrozen.org>
> 
> Add a new helper ieee80211_set_multiple_bssid_options() takes propagating
> the cfg80211 data down the stack.
> 
> The patch also makes sure that all members of the bss set will get closed
> when either of them is shutdown.

s/either/any/
> 
>  static int ieee80211_del_iface(struct wiphy *wiphy, struct wireless_dev *wdev)
>  {
> +	struct ieee80211_sub_if_data *sdata;
> +
> +	sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);

can be one line

> +	if (sdata && sdata->vif.type == NL80211_IFTYPE_AP) {
> +		if (sdata->vif.multiple_bssid.flags & IEEE80211_VIF_MBSS_TRANSMITTING) {
> +			struct ieee80211_sub_if_data *child;
> +
> +			rcu_read_lock();
> +			list_for_each_entry_rcu(child, &sdata->local->interfaces, list)
> +				if (child->vif.multiple_bssid.parent == &sdata->vif)
> +					dev_close(child->wdev.netdev);
> +			rcu_read_unlock();

You never tested this properly, this is wrong.

johannes

Re: [PATCH v9 2/4] mac80211: add multiple bssid support to interface handling

[Aloka Dixit]

On 2021-04-08 05:06, Johannes Berg wrote:
> On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
>> From: John Crispin <john@phrozen.org>
>> 
>> Add a new helper ieee80211_set_multiple_bssid_options() takes 
>> propagating
>> the cfg80211 data down the stack.
>> 
>> The patch also makes sure that all members of the bss set will get 
>> closed
>> when either of them is shutdown.
> 
> s/either/any/
>> 
>>  static int ieee80211_del_iface(struct wiphy *wiphy, struct 
>> wireless_dev *wdev)
>>  {
>> +	struct ieee80211_sub_if_data *sdata;
>> +
>> +	sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
> 
> can be one line
> 

Okay

>> +	if (sdata && sdata->vif.type == NL80211_IFTYPE_AP) {
>> +		if (sdata->vif.multiple_bssid.flags & 
>> IEEE80211_VIF_MBSS_TRANSMITTING) {
>> +			struct ieee80211_sub_if_data *child;
>> +
>> +			rcu_read_lock();
>> +			list_for_each_entry_rcu(child, &sdata->local->interfaces, list)
>> +				if (child->vif.multiple_bssid.parent == &sdata->vif)
>> +					dev_close(child->wdev.netdev);
>> +			rcu_read_unlock();
> 
> You never tested this properly, this is wrong.
> 
> johannes

This was added for graceful shutdown of non-transmitting interfaces 
whenever the transmitting one is being brought down. But I see that 
dev_close() is happening twice now.

Inclining towards removing this and just return error to application if 
it tries to remove transmitting before all non-transmitting are deleted.
However, currently the "parent" pointer to indicate the transmitting 
interface is maintained in mac80211, nothing in cfg80211.

Which option would be better,
(1) Add new function to mac80211_config_ops to return yes/no to whether 
cfg80211 can delete a particular interface when MBSSID is in use.
(2) Add a new pointer in struct wireless_dev to track the transmitting 
interface of the set. Then the yes/no decision can be taken in cfg80211 
itself.

Thanks.

Re: [PATCH v9 2/4] mac80211: add multiple bssid support to interface handling

[Johannes Berg]

Hi,

> > > +	if (sdata && sdata->vif.type == NL80211_IFTYPE_AP) {
> > > +		if (sdata->vif.multiple_bssid.flags & 
> > > IEEE80211_VIF_MBSS_TRANSMITTING) {
> > > +			struct ieee80211_sub_if_data *child;
> > > +
> > > +			rcu_read_lock();
> > > +			list_for_each_entry_rcu(child, &sdata->local->interfaces, list)
> > > +				if (child->vif.multiple_bssid.parent == &sdata->vif)
> > > +					dev_close(child->wdev.netdev);
> > > +			rcu_read_unlock();

> This was added for graceful shutdown of non-transmitting interfaces 
> whenever the transmitting one is being brought down. 
> 

I know, I asked you to.

> But I see that 
> dev_close() is happening twice now.
> 

That wouldn't be an issue.

The issue is that dev_close() needs to be able to sleep, and it even
contains a might_sleep(), so you can't do it under the RCU protection
you used here.

> Inclining towards removing this and just return error to application if 
> it tries to remove transmitting before all non-transmitting are deleted.
> However, currently the "parent" pointer to indicate the transmitting 
> interface is maintained in mac80211, nothing in cfg80211.

That seems kinda awkward, considering e.g. if hostapd crashes and then a
new instance has to clean up, it might not really have much knowledge of
the order in which it should be doing that.

I think it's better if you just fix the locking here?

johannes

Re: [PATCH v9 2/4] mac80211: add multiple bssid support to interface handling

[Aloka Dixit]

On 2021-04-19 04:28, Johannes Berg wrote:
> Hi,
> 
>> > > +	if (sdata && sdata->vif.type == NL80211_IFTYPE_AP) {
>> > > +		if (sdata->vif.multiple_bssid.flags &
>> > > IEEE80211_VIF_MBSS_TRANSMITTING) {
>> > > +			struct ieee80211_sub_if_data *child;
>> > > +
>> > > +			rcu_read_lock();
>> > > +			list_for_each_entry_rcu(child, &sdata->local->interfaces, list)
>> > > +				if (child->vif.multiple_bssid.parent == &sdata->vif)
>> > > +					dev_close(child->wdev.netdev);
>> > > +			rcu_read_unlock();
> 
>> This was added for graceful shutdown of non-transmitting interfaces
>> whenever the transmitting one is being brought down. 
>> 
> 
> I know, I asked you to.
> 
>> But I see that
>> dev_close() is happening twice now.
>> 
> 
> That wouldn't be an issue.
> 
> The issue is that dev_close() needs to be able to sleep, and it even
> contains a might_sleep(), so you can't do it under the RCU protection
> you used here.
> 
>> Inclining towards removing this and just return error to application 
>> if
>> it tries to remove transmitting before all non-transmitting are 
>> deleted.
>> However, currently the "parent" pointer to indicate the transmitting
>> interface is maintained in mac80211, nothing in cfg80211.
> 
> That seems kinda awkward, considering e.g. if hostapd crashes and then 
> a
> new instance has to clean up, it might not really have much knowledge 
> of
> the order in which it should be doing that.
> 
> I think it's better if you just fix the locking here?
> 
> johannes

Hi Johannes,
Thanks for the response, I need more help.

Is rcu_read_lock is not allowed around dev_close() because it might 
block or *ANY* lock?
Because both functions with new dev_close() themselves are called with 
locks held,
(1) ieee80211_do_stop() happens inside 
wiphy_lock(sdata->local->hw.wiphy)
(2) ieee80211_del_iface() happens inside mutex_lock(&rdev->wiphy.mtx).
Should these be unlocked temporarily too before calling dev_close()?
Didn't find any instance of wiphy.mtx lock/unlock in mac80211.

Also, in cfg.c, list_for_each_entry(sdata, &local->interfaces, list) is 
called with two different murexes: (1) local->iflist_mtx
(2) local->mtx

Which is the correct one for this purpose among above two and 
rcu_read_lock()?
Once that decided, would following be sufficient -
     lock()
     list_for_each_entry(sdata, &local->interfaces, list) {
         get_child_pointer
         unlock()
         dev_close()
         lock()
     }
     unlock

Thanks.

Re: [PATCH v9 2/4] mac80211: add multiple bssid support to interface handling

[Aloka Dixit]

On 2021-04-19 15:35, Aloka Dixit wrote:
> On 2021-04-19 04:28, Johannes Berg wrote:
>> Hi,
>> 
>>> > > +	if (sdata && sdata->vif.type == NL80211_IFTYPE_AP) {
>>> > > +		if (sdata->vif.multiple_bssid.flags &
>>> > > IEEE80211_VIF_MBSS_TRANSMITTING) {
>>> > > +			struct ieee80211_sub_if_data *child;
>>> > > +
>>> > > +			rcu_read_lock();
>>> > > +			list_for_each_entry_rcu(child, &sdata->local->interfaces, list)
>>> > > +				if (child->vif.multiple_bssid.parent == &sdata->vif)
>>> > > +					dev_close(child->wdev.netdev);
>>> > > +			rcu_read_unlock();
>> 
>>> This was added for graceful shutdown of non-transmitting interfaces
>>> whenever the transmitting one is being brought down. 
>>> 
>> 
>> I know, I asked you to.
>> 
>>> But I see that
>>> dev_close() is happening twice now.
>>> 
>> 
>> That wouldn't be an issue.
>> 
>> The issue is that dev_close() needs to be able to sleep, and it even
>> contains a might_sleep(), so you can't do it under the RCU protection
>> you used here.
>> 
>>> Inclining towards removing this and just return error to application 
>>> if
>>> it tries to remove transmitting before all non-transmitting are 
>>> deleted.
>>> However, currently the "parent" pointer to indicate the transmitting
>>> interface is maintained in mac80211, nothing in cfg80211.
>> 
>> That seems kinda awkward, considering e.g. if hostapd crashes and then 
>> a
>> new instance has to clean up, it might not really have much knowledge 
>> of
>> the order in which it should be doing that.
>> 
>> I think it's better if you just fix the locking here?
>> 
>> johannes
> 
> Hi Johannes,
> Thanks for the response, I need more help.
> 
> Is rcu_read_lock is not allowed around dev_close() because it might
> block or *ANY* lock?
> Because both functions with new dev_close() themselves are called with
> locks held,
> (1) ieee80211_do_stop() happens inside 
> wiphy_lock(sdata->local->hw.wiphy)
> (2) ieee80211_del_iface() happens inside mutex_lock(&rdev->wiphy.mtx).
> Should these be unlocked temporarily too before calling dev_close()?
> Didn't find any instance of wiphy.mtx lock/unlock in mac80211.
> 

My bad, wiphy_lock() internally uses wiphy.mtx so mac80211 does have a 
way, then should it be unlocked temporarily before dev_close()?

> Also, in cfg.c, list_for_each_entry(sdata, &local->interfaces, list)
> is called with two different murexes: (1) local->iflist_mtx
> (2) local->mtx
> 
> Which is the correct one for this purpose among above two and 
> rcu_read_lock()?
> Once that decided, would following be sufficient -
>     lock()
>     list_for_each_entry(sdata, &local->interfaces, list) {
>         get_child_pointer
>         unlock()
>         dev_close()
>         lock()
>     }
>     unlock
> 
> Thanks.

Re: [PATCH v9 2/4] mac80211: add multiple bssid support to interface handling

[Johannes Berg]

Hi Aloka,
> 
> Is rcu_read_lock is not allowed around dev_close() because it might 
> block or *ANY* lock?

Well, I guess it's more nuanced than that.

rcu_read_lock() is not allowed because it enters an atomic context.
Similarly not allowed would be spinlocks, or local_bh_disable, or any
similar thing that makes the context atomic.

From a locking perspective, normal mutexes *would* be allowed.

However, you'd have to be extremely careful to not allow recursion,
since dev_close() will call back into cfg80211/mac80211.

> Because both functions with new dev_close() themselves are called with 
> locks held,
> (1) ieee80211_do_stop() happens inside 
> wiphy_lock(sdata->local->hw.wiphy)

This is probably already problematic.

> (2) ieee80211_del_iface() happens inside mutex_lock(&rdev->wiphy.mtx).

As you discovered, that's the same lock.

> Should these be unlocked temporarily too before calling dev_close()?

I don't think temporarily dropping locks is ever a good idea, it makes
it really hard to reason about the code.

But we already do this for AP-VLAN interfaces, so not sure why this is
so different?
> 
> Also, in cfg.c, list_for_each_entry(sdata, &local->interfaces, list) is 
> called with two different murexes: (1) local->iflist_mtx
> (2) local->mtx


> 
> Which is the correct one for this purpose among above two and 
> rcu_read_lock()?
> Once that decided, would following be sufficient -
>      lock()
>      list_for_each_entry(sdata, &local->interfaces, list) {
>          get_child_pointer
>          unlock()
>          dev_close()

What guarantees you don't lose the device after the unlock()? I think
you'd risk list corruption here this way...

Look at the other instance of dev_close() here - as long as you can
guarantee there won't be recursion (and you do, because non-transmitting
interfaces don't have other non-transmitting below them, though they may
actually have AP-VLANs!), we should be fine just doing it like that
code?

johannes

[PATCH v9 3/4] mac80211: add multiple bssid/EMA support to beacon handling

[Aloka Dixit]

From: John Crispin <john@phrozen.org>

With beacon_data now holding the additional information about the multiple
bssid elements, we need to honour these in the various beacon handling
code paths.

Extend ieee80211_beacon_get_template() to allow generation of multiple
bssid/EMA beacons. The API provides support for HW that can offload the
EMA beaconing aswell as HW that will require periodic updates of the
beacon template upon completion events.

In case the HW can do full EMA offload, functions are provided that allow
the driver to get a list of the periodicity number of beacons and their
matching mutable offsets.

Signed-off-by: John Crispin <john@phrozen.org>
Co-developed-by: Aloka Dixit <alokad@codeaurora.org>
Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
---
 include/net/mac80211.h     |  86 +++++++++++++++++
 net/mac80211/cfg.c         | 114 +++++++++++++++++++---
 net/mac80211/ieee80211_i.h |   2 +
 net/mac80211/tx.c          | 189 ++++++++++++++++++++++++++++++++-----
 4 files changed, 359 insertions(+), 32 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index b9f51515c2e8..fc456262b335 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -4889,12 +4889,17 @@ void ieee80211_report_low_ack(struct ieee80211_sta *sta, u32 num_packets);
  * @cntdwn_counter_offs: array of IEEE80211_MAX_CNTDWN_COUNTERS_NUM offsets
  *	to countdown counters.  This array can contain zero values which
  *	should be ignored.
+ * @multiple_bssid_offset: position of the multiple bssid element
+ * @multiple_bssid_length: size of the multiple bssid element
  */
 struct ieee80211_mutable_offsets {
 	u16 tim_offset;
 	u16 tim_length;
 
 	u16 cntdwn_counter_offs[IEEE80211_MAX_CNTDWN_COUNTERS_NUM];
+
+	u16 multiple_bssid_offset;
+	u16 multiple_bssid_length;
 };
 
 /**
@@ -4921,6 +4926,87 @@ ieee80211_beacon_get_template(struct ieee80211_hw *hw,
 			      struct ieee80211_vif *vif,
 			      struct ieee80211_mutable_offsets *offs);
 
+/**
+ * enum ieee80211_bcn_tmpl_ema - EMA beacon generation type
+ * @IEEE80211_BCN_EMA_NONE: don't generate an EMA beacon.
+ * @IEEE80211_BCN_EMA_NEXT: generate the next periodicity beacon.
+ * @IEEE80211_BCN_EMA_INDEX: generate beacon by periodicity index
+ *	if the value is >= this enum value.
+ */
+enum ieee80211_bcn_tmpl_ema {
+	IEEE80211_BCN_EMA_NONE	= -2,
+	IEEE80211_BCN_EMA_NEXT	= -1,
+	IEEE80211_BCN_EMA_INDEX	= 0,
+};
+
+/**
+ * ieee80211_beacon_get_template_ema_next - EMA beacon template generation
+ *	function for drivers using the sw offload path.
+ * @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.
+ *
+ * This function differs from ieee80211_beacon_get_template in the sense that
+ * it generates EMA VAP templates. When we use multiple_bssid, the beacons can
+ * get very large costing a lot of airtime. To work around this, we iterate
+ * over the multiple bssid elements and only send one inside the beacon for
+ * 1..n. Calling this function will auto-increment the periodicity counter.
+ *
+ * This function needs to follow the same rules as ieee80211_beacon_get_template
+ *
+ * Return: The beacon template. %NULL on error.
+ */
+struct sk_buff *ieee80211_beacon_get_template_ema_next(struct ieee80211_hw *hw,
+						       struct ieee80211_vif *vif,
+						       struct ieee80211_mutable_offsets *offs);
+
+/**
+ * struct ieee80211_ema_bcn_list - list entry of an EMA beacon
+ * @list: the list pointer.
+ * @skb: the skb containing this specific beacon
+ * @offs: &struct ieee80211_mutable_offsets pointer to struct that will
+ *	receive the offsets that may be updated by the driver.
+ */
+struct ieee80211_ema_bcn_list {
+	struct list_head list;
+	struct sk_buff *skb;
+	struct ieee80211_mutable_offsets offs;
+};
+
+/**
+ * ieee80211_beacon_get_template_ema_list - EMA beacon template generation
+ *	function for drivers using the hw offload.
+ * @hw: pointer obtained from ieee80211_alloc_hw().
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
+ * @head: linked list head that will get populated with
+ *	&struct ieee80211_ema_bcn_list pointers.
+ *
+ * This function differs from ieee80211_beacon_get_template in the sense that
+ * it generates EMA VAP templates. When we use multiple_bssid, the beacons can
+ * get very large costing a lot of airtime. To work around this, we iterate
+ * over the multiple bssid elements and only send one inside the beacon for
+ * 1..n. This function will populate a linked list that the driver can pass
+ * to the HW.
+ *
+ * This function needs to follow the same rules as ieee80211_beacon_get_template
+ *
+ * Return: The nuber of entries in the list or 0 on error.
+ */
+
+int ieee80211_beacon_get_template_ema_list(struct ieee80211_hw *hw,
+					   struct ieee80211_vif *vif,
+					   struct list_head *head);
+
+/**
+ * ieee80211_beacon_free_ema_list - free an EMA beacon template list
+ * @head: linked list head containing &struct ieee80211_ema_bcn_list pointers.
+ *
+ * This function will free a list previously acquired by calling
+ * ieee80211_beacon_get_template_ema_list()
+ */
+void ieee80211_beacon_free_ema_list(struct list_head *head);
+
 /**
  * ieee80211_beacon_get_tim - beacon generation function
  * @hw: pointer obtained from ieee80211_alloc_hw().
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 91e659a43f67..e72c0a4a26c3 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -984,14 +984,49 @@ static int ieee80211_set_ftm_responder_params(
 	return 0;
 }
 
+static int ieee80211_get_multiple_bssid_beacon_len(struct cfg80211_multiple_bssid_data *data)
+{
+	int i, len = 0;
+
+	if (!data)
+		return 0;
+
+	for (i = 0; i < data->cnt; i++)
+		len += data->elems[i].len;
+
+	return len;
+}
+
+static u8 *ieee80211_copy_multiple_bssid_beacon(u8 *offset,
+						struct cfg80211_multiple_bssid_data *dest,
+						struct cfg80211_multiple_bssid_data *src)
+{
+	int i;
+
+	if (!dest || !src)
+		return offset;
+
+	dest->cnt = src->cnt;
+	for (i = 0; i < dest->cnt; i++) {
+		dest->elems[i].len = src->elems[i].len;
+		dest->elems[i].data = offset;
+		memcpy(dest->elems[i].data, src->elems[i].data,
+		       dest->elems[i].len);
+		offset += dest->elems[i].len;
+	}
+
+	return offset;
+}
+
 static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
 				   struct cfg80211_beacon_data *params,
 				   const struct ieee80211_csa_settings *csa)
 {
 	struct beacon_data *new, *old;
-	int new_head_len, new_tail_len;
+	int new_head_len, new_tail_len, new_multiple_bssid_len = 0;
 	int size, err;
 	u32 changed = BSS_CHANGED_BEACON;
+	u8 *new_multiple_bssid_offset;
 
 	old = sdata_dereference(sdata->u.ap.beacon, sdata);
 
@@ -1013,12 +1048,30 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
 	else
 		new_tail_len = old->tail_len;
 
-	size = sizeof(*new) + new_head_len + new_tail_len;
+	/* new or old multiple_bssid? */
+	if (params->multiple_bssid)
+		new_multiple_bssid_len =
+			ieee80211_get_multiple_bssid_beacon_len(params->multiple_bssid);
+	else if (old && old->multiple_bssid)
+		new_multiple_bssid_len =
+			ieee80211_get_multiple_bssid_beacon_len(old->multiple_bssid);
+
+	size = sizeof(*new) + new_head_len + new_tail_len +
+	       new_multiple_bssid_len;
 
 	new = kzalloc(size, GFP_KERNEL);
 	if (!new)
 		return -ENOMEM;
 
+	if (new_multiple_bssid_len) {
+		new->multiple_bssid = kzalloc(sizeof(*params->multiple_bssid),
+					      GFP_KERNEL);
+		if (!new->multiple_bssid) {
+			kfree(new);
+			return -ENOMEM;
+		}
+	}
+
 	/* start filling the new info now */
 
 	/*
@@ -1030,6 +1083,17 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
 	new->head_len = new_head_len;
 	new->tail_len = new_tail_len;
 
+	/* copy in optional multiple_bssid_ies */
+	new_multiple_bssid_offset = new->tail + new_tail_len;
+	if (params->multiple_bssid)
+		ieee80211_copy_multiple_bssid_beacon(new_multiple_bssid_offset,
+						     new->multiple_bssid,
+						     params->multiple_bssid);
+	else if (old && old->multiple_bssid)
+		ieee80211_copy_multiple_bssid_beacon(new_multiple_bssid_offset,
+						     new->multiple_bssid,
+						     old->multiple_bssid);
+
 	if (csa) {
 		new->cntdwn_current_counter = csa->count;
 		memcpy(new->cntdwn_counter_offsets, csa->counter_offsets_beacon,
@@ -1053,6 +1117,7 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
 	err = ieee80211_set_probe_resp(sdata, params->probe_resp,
 				       params->probe_resp_len, csa);
 	if (err < 0) {
+		kfree(new->multiple_bssid);
 		kfree(new);
 		return err;
 	}
@@ -1068,6 +1133,7 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
 							 params->civicloc_len);
 
 		if (err < 0) {
+			kfree(new->multiple_bssid);
 			kfree(new);
 			return err;
 		}
@@ -1077,9 +1143,10 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
 
 	rcu_assign_pointer(sdata->u.ap.beacon, new);
 
-	if (old)
+	if (old) {
+		kfree(old->multiple_bssid);
 		kfree_rcu(old, rcu_head);
-
+	}
 	return changed;
 }
 
@@ -1234,8 +1301,10 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 	if (err) {
 		old = sdata_dereference(sdata->u.ap.beacon, sdata);
 
-		if (old)
+		if (old) {
+			kfree(old->multiple_bssid);
 			kfree_rcu(old, rcu_head);
+		}
 		RCU_INIT_POINTER(sdata->u.ap.beacon, NULL);
 		goto error;
 	}
@@ -1315,8 +1384,11 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 
 	mutex_unlock(&local->mtx);
 
-	kfree(sdata->u.ap.next_beacon);
-	sdata->u.ap.next_beacon = NULL;
+	if (sdata->u.ap.next_beacon) {
+		kfree(sdata->u.ap.next_beacon->multiple_bssid);
+		kfree(sdata->u.ap.next_beacon);
+		sdata->u.ap.next_beacon = NULL;
+	}
 
 	/* turn off carrier for this interface and dependent VLANs */
 	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
@@ -1328,6 +1400,7 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	RCU_INIT_POINTER(sdata->u.ap.probe_resp, NULL);
 	RCU_INIT_POINTER(sdata->u.ap.fils_discovery, NULL);
 	RCU_INIT_POINTER(sdata->u.ap.unsol_bcast_probe_resp, NULL);
+	kfree(old_beacon->multiple_bssid);
 	kfree_rcu(old_beacon, rcu_head);
 	if (old_probe_resp)
 		kfree_rcu(old_probe_resp, rcu_head);
@@ -3084,13 +3157,24 @@ cfg80211_beacon_dup(struct cfg80211_beacon_data *beacon)
 
 	len = beacon->head_len + beacon->tail_len + beacon->beacon_ies_len +
 	      beacon->proberesp_ies_len + beacon->assocresp_ies_len +
-	      beacon->probe_resp_len + beacon->lci_len + beacon->civicloc_len;
+	      beacon->probe_resp_len + beacon->lci_len + beacon->civicloc_len +
+	      ieee80211_get_multiple_bssid_beacon_len(beacon->multiple_bssid);
 
 	new_beacon = kzalloc(sizeof(*new_beacon) + len, GFP_KERNEL);
 	if (!new_beacon)
 		return NULL;
 
+	if (beacon->multiple_bssid) {
+		new_beacon->multiple_bssid = kzalloc(sizeof(*beacon->multiple_bssid),
+						     GFP_KERNEL);
+		if (!new_beacon->multiple_bssid) {
+			kfree(new_beacon);
+			return NULL;
+		}
+	}
+
 	pos = (u8 *)(new_beacon + 1);
+
 	if (beacon->head_len) {
 		new_beacon->head_len = beacon->head_len;
 		new_beacon->head = pos;
@@ -3127,6 +3211,10 @@ cfg80211_beacon_dup(struct cfg80211_beacon_data *beacon)
 		memcpy(pos, beacon->probe_resp, beacon->probe_resp_len);
 		pos += beacon->probe_resp_len;
 	}
+	if (beacon->multiple_bssid && beacon->multiple_bssid->cnt)
+		pos = ieee80211_copy_multiple_bssid_beacon(pos,
+							   new_beacon->multiple_bssid,
+							   beacon->multiple_bssid);
 
 	/* might copy -1, meaning no changes requested */
 	new_beacon->ftm_responder = beacon->ftm_responder;
@@ -3164,8 +3252,11 @@ static int ieee80211_set_after_csa_beacon(struct ieee80211_sub_if_data *sdata,
 	case NL80211_IFTYPE_AP:
 		err = ieee80211_assign_beacon(sdata, sdata->u.ap.next_beacon,
 					      NULL);
-		kfree(sdata->u.ap.next_beacon);
-		sdata->u.ap.next_beacon = NULL;
+		if (sdata->u.ap.next_beacon) {
+			kfree(sdata->u.ap.next_beacon->multiple_bssid);
+			kfree(sdata->u.ap.next_beacon);
+			sdata->u.ap.next_beacon = NULL;
+		}
 
 		if (err < 0)
 			return err;
@@ -3330,7 +3421,8 @@ static int ieee80211_set_csa_beacon(struct ieee80211_sub_if_data *sdata,
 		csa.count = params->count;
 
 		err = ieee80211_assign_beacon(sdata, &params->beacon_csa, &csa);
-		if (err < 0) {
+		if (err < 0 && sdata->u.ap.next_beacon) {
+			kfree(sdata->u.ap.next_beacon->multiple_bssid);
 			kfree(sdata->u.ap.next_beacon);
 			return err;
 		}
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index ecda126a7026..d30d53cfec1a 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -261,6 +261,8 @@ struct beacon_data {
 	struct ieee80211_meshconf_ie *meshconf;
 	u16 cntdwn_counter_offsets[IEEE80211_MAX_CNTDWN_COUNTERS_NUM];
 	u8 cntdwn_current_counter;
+	struct cfg80211_multiple_bssid_data *multiple_bssid;
+	u16 ema_index;
 	struct rcu_head rcu_head;
 };
 
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 5d06de61047a..5cdf977e7289 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -4724,11 +4724,71 @@ static int ieee80211_beacon_protect(struct sk_buff *skb,
 	return 0;
 }
 
+static int ieee80211_beacon_multiple_bssid_len(struct beacon_data *beacon,
+					       int index)
+{
+	int len = 0, i;
+
+	if (index == IEEE80211_BCN_EMA_NEXT) {
+		index = beacon->ema_index;
+		beacon->ema_index++;
+		beacon->ema_index %= beacon->multiple_bssid->cnt;
+	}
+
+	if (index != IEEE80211_BCN_EMA_NONE &&
+	    index >= beacon->multiple_bssid->cnt)
+		return -1;
+
+	if (beacon->multiple_bssid->cnt) {
+		if (index >= IEEE80211_BCN_EMA_INDEX) {
+			len = beacon->multiple_bssid->elems[index].len;
+		} else {
+			for (i = 0; i < beacon->multiple_bssid->cnt; i++)
+				len += beacon->multiple_bssid->elems[i].len;
+		}
+	}
+	return len;
+}
+
+static void
+ieee80211_beacon_add_multiple_bssid_config(struct ieee80211_vif *vif,
+					   struct sk_buff *skb,
+					   struct cfg80211_multiple_bssid_data *config)
+{
+	u8 *pos = skb_put(skb, 5);
+
+	*pos++ = WLAN_EID_EXTENSION;
+	*pos++ = 3;
+	*pos++ = WLAN_EID_EXT_MULTIPLE_BSSID_CONFIGURATION;
+	*pos++ = vif->bss_conf.multiple_bssid.count;
+	*pos++ = config->cnt;
+}
+
+static void
+ieee80211_beacon_add_multiple_bssid(struct ieee80211_vif *vif,
+				    struct sk_buff *skb,
+				    struct cfg80211_multiple_bssid_data *config,
+				    int index)
+{
+	if (index >= IEEE80211_BCN_EMA_INDEX) {
+		ieee80211_beacon_add_multiple_bssid_config(vif, skb, config);
+		skb_put_data(skb, config->elems[index].data,
+			     config->elems[index].len);
+	} else {
+		int i;
+
+		for (i = 0; i < config->cnt; i++)
+			skb_put_data(skb, config->elems[i].data,
+				     config->elems[i].len);
+	}
+}
+
 static struct sk_buff *
 __ieee80211_beacon_get(struct ieee80211_hw *hw,
 		       struct ieee80211_vif *vif,
 		       struct ieee80211_mutable_offsets *offs,
-		       bool is_template)
+		       bool is_template,
+		       int ema_index)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
 	struct beacon_data *beacon = NULL;
@@ -4740,13 +4800,11 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 	struct ieee80211_chanctx_conf *chanctx_conf;
 	int csa_off_base = 0;
 
-	rcu_read_lock();
-
 	sdata = vif_to_sdata(vif);
 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 
 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
-		goto out;
+		return NULL;
 
 	if (offs)
 		memset(offs, 0, sizeof(*offs));
@@ -4756,6 +4814,9 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 
 		beacon = rcu_dereference(ap->beacon);
 		if (beacon) {
+			int multiple_bssid_elems_len = 0;
+			int multiple_bssid_config_len = 5;
+
 			if (beacon->cntdwn_counter_offsets[0]) {
 				if (!is_template)
 					ieee80211_beacon_update_cntdwn(vif);
@@ -4763,6 +4824,14 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 				ieee80211_set_beacon_cntdwn(sdata, beacon);
 			}
 
+			if (beacon->multiple_bssid) {
+				multiple_bssid_elems_len =
+					ieee80211_beacon_multiple_bssid_len(beacon,
+									    ema_index);
+				if (multiple_bssid_elems_len == -1)
+					return NULL;
+			}
+
 			/*
 			 * headroom, head length,
 			 * tail length and maximum TIM length
@@ -4770,9 +4839,11 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 			skb = dev_alloc_skb(local->tx_headroom +
 					    beacon->head_len +
 					    beacon->tail_len + 256 +
-					    local->hw.extra_beacon_tailroom);
+					    local->hw.extra_beacon_tailroom +
+					    multiple_bssid_config_len +
+					    multiple_bssid_elems_len);
 			if (!skb)
-				goto out;
+				return NULL;
 
 			skb_reserve(skb, local->tx_headroom);
 			skb_put_data(skb, beacon->head, beacon->head_len);
@@ -4788,21 +4859,32 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 				csa_off_base = skb->len;
 			}
 
+			if (multiple_bssid_elems_len) {
+				ieee80211_beacon_add_multiple_bssid(vif, skb,
+								    beacon->multiple_bssid,
+								    ema_index);
+				if (offs) {
+					offs->multiple_bssid_offset = skb->len -
+								      multiple_bssid_elems_len;
+					csa_off_base = skb->len;
+				}
+			}
+
 			if (beacon->tail)
 				skb_put_data(skb, beacon->tail,
 					     beacon->tail_len);
 
 			if (ieee80211_beacon_protect(skb, local, sdata) < 0)
-				goto out;
+				return NULL;
 		} else
-			goto out;
+			return NULL;
 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 		struct ieee80211_hdr *hdr;
 
 		beacon = rcu_dereference(ifibss->presp);
 		if (!beacon)
-			goto out;
+			return NULL;
 
 		if (beacon->cntdwn_counter_offsets[0]) {
 			if (!is_template)
@@ -4814,7 +4896,7 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 		skb = dev_alloc_skb(local->tx_headroom + beacon->head_len +
 				    local->hw.extra_beacon_tailroom);
 		if (!skb)
-			goto out;
+			return NULL;
 		skb_reserve(skb, local->tx_headroom);
 		skb_put_data(skb, beacon->head, beacon->head_len);
 
@@ -4826,7 +4908,7 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 
 		beacon = rcu_dereference(ifmsh->beacon);
 		if (!beacon)
-			goto out;
+			return NULL;
 
 		if (beacon->cntdwn_counter_offsets[0]) {
 			if (!is_template)
@@ -4849,7 +4931,7 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 				    beacon->tail_len +
 				    local->hw.extra_beacon_tailroom);
 		if (!skb)
-			goto out;
+			return NULL;
 		skb_reserve(skb, local->tx_headroom);
 		skb_put_data(skb, beacon->head, beacon->head_len);
 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb, is_template);
@@ -4862,7 +4944,7 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 		skb_put_data(skb, beacon->tail, beacon->tail_len);
 	} else {
 		WARN_ON(1);
-		goto out;
+		return NULL;
 	}
 
 	/* CSA offsets */
@@ -4905,27 +4987,92 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
 			IEEE80211_TX_CTL_ASSIGN_SEQ |
 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
- 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)
+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);
+	struct sk_buff *bcn;
+
+	rcu_read_lock();
+	bcn = __ieee80211_beacon_get(hw, vif, offs, true,
+				     IEEE80211_BCN_EMA_NONE);
+	rcu_read_unlock();
+
+	return bcn;
 }
 EXPORT_SYMBOL(ieee80211_beacon_get_template);
 
+struct sk_buff *ieee80211_beacon_get_template_ema_next(struct ieee80211_hw *hw,
+						       struct ieee80211_vif *vif,
+						       struct ieee80211_mutable_offsets *offs)
+{
+	struct sk_buff *bcn;
+
+	rcu_read_lock();
+	bcn = __ieee80211_beacon_get(hw, vif, offs, true,
+				     IEEE80211_BCN_EMA_NEXT);
+	rcu_read_unlock();
+
+	return bcn;
+}
+EXPORT_SYMBOL(ieee80211_beacon_get_template_ema_next);
+
+void ieee80211_beacon_free_ema_list(struct list_head *head)
+{
+	struct ieee80211_ema_bcn_list *ema, *tmp;
+
+	list_for_each_entry_safe(ema, tmp, head, list) {
+		kfree_skb(ema->skb);
+		kfree(ema);
+	}
+}
+EXPORT_SYMBOL(ieee80211_beacon_free_ema_list);
+
+int
+ieee80211_beacon_get_template_ema_list(struct ieee80211_hw *hw,
+				       struct ieee80211_vif *vif,
+				       struct list_head *head)
+{
+	int cnt = 0;
+
+	rcu_read_lock();
+	while (true) {
+		struct ieee80211_ema_bcn_list *ema;
+
+		ema = kmalloc(sizeof(*ema), GFP_KERNEL);
+		if (!ema) {
+			ieee80211_beacon_free_ema_list(head);
+			cnt = 0;
+			goto out;
+		}
+
+		ema->skb = __ieee80211_beacon_get(hw, vif, &ema->offs, true,
+						  cnt);
+		if (!ema->skb) {
+			kfree(ema);
+			break;
+		}
+		list_add_tail(&ema->list, head);
+		cnt++;
+	}
+out:
+	rcu_read_unlock();
+
+	return cnt;
+}
+EXPORT_SYMBOL(ieee80211_beacon_get_template_ema_list);
+
 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);
+	struct sk_buff *bcn = __ieee80211_beacon_get(hw, vif, &offs, false,
+						     IEEE80211_BCN_EMA_NONE);
 	struct sk_buff *copy;
 	struct ieee80211_supported_band *sband;
 	int shift;
-- 
2.25.0

Re: [PATCH v9 3/4] mac80211: add multiple bssid/EMA support to beacon handling

[Johannes Berg]

On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
> 
> +/**
> + * enum ieee80211_bcn_tmpl_ema - EMA beacon generation type
> + * @IEEE80211_BCN_EMA_NONE: don't generate an EMA beacon.
> + * @IEEE80211_BCN_EMA_NEXT: generate the next periodicity beacon.
> + * @IEEE80211_BCN_EMA_INDEX: generate beacon by periodicity index
> + *	if the value is >= this enum value.
> + */
> +enum ieee80211_bcn_tmpl_ema {
> +	IEEE80211_BCN_EMA_NONE	= -2,
> +	IEEE80211_BCN_EMA_NEXT	= -1,
> +	IEEE80211_BCN_EMA_INDEX	= 0,

Maybe call it _BASE instead of _INDEX, it's not really meant to be used
as is?

> +static u8 *ieee80211_copy_multiple_bssid_beacon(u8 *offset,
> +						struct cfg80211_multiple_bssid_data *dest,
> +						struct cfg80211_multiple_bssid_data *src)
> +{
> +	int i;
> +
> +	if (!dest || !src)
> +		return offset;
> +
> +	dest->cnt = src->cnt;
> +	for (i = 0; i < dest->cnt; i++) {
> +		dest->elems[i].len = src->elems[i].len;
> +		dest->elems[i].data = offset;
> +		memcpy(dest->elems[i].data, src->elems[i].data,
> +		       dest->elems[i].len);
> +		offset += dest->elems[i].len;
> +	}


Following my earlier question - here you just copy all the elements one
after another, as far as I can tell, so why did they need to be separate
in the first place? Might be a lot simpler everywhere if all of this was
just a single buffer, starting from the userspace API?


> @@ -4740,13 +4800,11 @@ __ieee80211_beacon_get(struct ieee80211_hw *hw,
>  	struct ieee80211_chanctx_conf *chanctx_conf;
>  	int csa_off_base = 0;

> -	rcu_read_lock();
> -
>  	sdata = vif_to_sdata(vif);
>  	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);

OK, but ...

>  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);
> +	struct sk_buff *bcn = __ieee80211_beacon_get(hw, vif, &offs, false,
> +						     IEEE80211_BCN_EMA_NONE);

You didn't add the protection everywhere.

johannes

Re: [PATCH v9 3/4] mac80211: add multiple bssid/EMA support to beacon handling

[Aloka Dixit]

On 2021-04-08 05:11, Johannes Berg wrote:
> On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
>> 
>> +/**
>> + * enum ieee80211_bcn_tmpl_ema - EMA beacon generation type
>> + * @IEEE80211_BCN_EMA_NONE: don't generate an EMA beacon.
>> + * @IEEE80211_BCN_EMA_NEXT: generate the next periodicity beacon.
>> + * @IEEE80211_BCN_EMA_INDEX: generate beacon by periodicity index
>> + *	if the value is >= this enum value.
>> + */
>> +enum ieee80211_bcn_tmpl_ema {
>> +	IEEE80211_BCN_EMA_NONE	= -2,
>> +	IEEE80211_BCN_EMA_NEXT	= -1,
>> +	IEEE80211_BCN_EMA_INDEX	= 0,
> 
> Maybe call it _BASE instead of _INDEX, it's not really meant to be used
> as is?
> 

Sure

>> +static u8 *ieee80211_copy_multiple_bssid_beacon(u8 *offset,
>> +						struct cfg80211_multiple_bssid_data *dest,
>> +						struct cfg80211_multiple_bssid_data *src)
>> +{
>> +	int i;
>> +
>> +	if (!dest || !src)
>> +		return offset;
>> +
>> +	dest->cnt = src->cnt;
>> +	for (i = 0; i < dest->cnt; i++) {
>> +		dest->elems[i].len = src->elems[i].len;
>> +		dest->elems[i].data = offset;
>> +		memcpy(dest->elems[i].data, src->elems[i].data,
>> +		       dest->elems[i].len);
>> +		offset += dest->elems[i].len;
>> +	}
> 
> 
> Following my earlier question - here you just copy all the elements one
> after another, as far as I can tell, so why did they need to be 
> separate
> in the first place? Might be a lot simpler everywhere if all of this 
> was
> just a single buffer, starting from the userspace API?
> 
> 

Separate buffers required as only one buffer is copied when
(ema_index >= IEEE80211_BCN_EMA_INDEX) in
__ieee80211_beacon_get().


>> @@ -4740,13 +4800,11 @@ __ieee80211_beacon_get(struct ieee80211_hw 
>> *hw,
>>  	struct ieee80211_chanctx_conf *chanctx_conf;
>>  	int csa_off_base = 0;
> 
>> -	rcu_read_lock();
>> -
>>  	sdata = vif_to_sdata(vif);
>>  	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
> 
> OK, but ...
> 
>>  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);
>> +	struct sk_buff *bcn = __ieee80211_beacon_get(hw, vif, &offs, false,
>> +						     IEEE80211_BCN_EMA_NONE);
> 
> You didn't add the protection everywhere.
> 

Will revise this part, thanks for bringing it up.

> johannes

[PATCH v9 4/4] mac80211: CSA on non-transmitting interfaces

[Aloka Dixit]

From: John Crispin <john@phrozen.org>

Trigger ieee80211_csa_finish() on the non-transmitting interfaces when
CSA concludes on the tranmitting interface.

Modify offset in beacon generation to reflect multiple BSSID element
length.

Signed-off-by: John Crispin <john@phrozen.org>
Co-developed-by: Aloka Dixit <alokad@codeaurora.org>
Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
---
 net/mac80211/cfg.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index e72c0a4a26c3..ccafa39f7ad6 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3238,6 +3238,17 @@ void ieee80211_csa_finish(struct ieee80211_vif *vif)
 {
 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 
+	if (sdata->vif.multiple_bssid.flags & IEEE80211_VIF_MBSS_TRANSMITTING) {
+		struct ieee80211_sub_if_data *child;
+
+		rcu_read_lock();
+		list_for_each_entry_rcu(child, &sdata->local->interfaces, list)
+			if (child->vif.multiple_bssid.parent == &sdata->vif)
+				ieee80211_queue_work(&child->local->hw,
+						     &child->csa_finalize_work);
+		rcu_read_unlock();
+	}
+
 	ieee80211_queue_work(&sdata->local->hw,
 			     &sdata->csa_finalize_work);
 }
-- 
2.25.0

Re: [PATCH v9 0/4] Multiple BSSID support

[Johannes Berg]

On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
> This patchset adds support for multiple BSSID and
> enhanced multi-BSSID advertisements.

All of this, in particular the subjects, should really mention that it's
for AP side.

Does it apply also for mesh, btw?

johannes

Re: [PATCH v9 0/4] Multiple BSSID support

[Aloka Dixit]

On 2021-04-08 04:53, Johannes Berg wrote:
> On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
>> This patchset adds support for multiple BSSID and
>> enhanced multi-BSSID advertisements.
> 
> All of this, in particular the subjects, should really mention that 
> it's
> for AP side.
> 
> Does it apply also for mesh, btw?
> 
> johannes

No, this patchset is only for AP mode.
Will mention it in the titles/commit_logs/comments.
Thanks.

Re: [PATCH v9 0/4] Multiple BSSID support

[Johannes Berg]

On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
> This patchset adds support for multiple BSSID and
> enhanced multi-BSSID advertisements.
> 
> This version modifies only nl80211 patch (1/4) which describes
> the difference.
> 
> John Crispin (4):
>   nl80211: add basic multiple bssid support
>   mac80211: add multiple bssid support to interface handling
>   mac80211: add multiple bssid/EMA support to beacon handling
>   mac80211: CSA on non-transmitting interfaces

Also, can we have hwsim support for proper testing? Seems with all the
logic in mac80211 to give you the right beacons etc. that should be
really simple?

johannes

Re: [PATCH v9 0/4] Multiple BSSID support

[Aloka Dixit]

On 2021-04-08 05:17, Johannes Berg wrote:
> On Wed, 2021-03-10 at 10:26 -0800, Aloka Dixit wrote:
>> This patchset adds support for multiple BSSID and
>> enhanced multi-BSSID advertisements.
>> 
>> This version modifies only nl80211 patch (1/4) which describes
>> the difference.
>> 
>> John Crispin (4):
>>   nl80211: add basic multiple bssid support
>>   mac80211: add multiple bssid support to interface handling
>>   mac80211: add multiple bssid/EMA support to beacon handling
>>   mac80211: CSA on non-transmitting interfaces
> 
> Also, can we have hwsim support for proper testing? Seems with all the
> logic in mac80211 to give you the right beacons etc. that should be
> really simple?
> 
> johannes

Sure, will add hwsim tests.

BTW, do you see value in replacing all occurrences
of *_multiple_bssid_* with *_mbssid_* (also in new
nl80211 attributes).
Most lines needed to be split because of 80 character
boundary, so this replacement will make that code
look cleaner. I have avoided it till now to reduce
number of changes between versions.
Thanks.

Re: [PATCH v9 0/4] Multiple BSSID support

[Johannes Berg]

On Fri, 2021-04-09 at 11:31 -0700, Aloka Dixit wrote:
> 
> BTW, do you see value in replacing all occurrences
> of *_multiple_bssid_* with *_mbssid_* (also in new
> nl80211 attributes).
> Most lines needed to be split because of 80 character
> boundary, so this replacement will make that code
> look cleaner. I have avoided it till now to reduce
> number of changes between versions.

Might be nicer, but I can live with the longer identifiers too. I don't
really mind if you do it between versions though, so feel free.

johannes