wifi: mac80211: generate EMA beacons in AP mode

Add APIs to generate an array of beacons for an EMA AP (enhanced
multiple BSSID advertisements), each including a single MBSSID element.
EMA profile periodicity equals the count of elements.

- ieee80211_beacon_get_template_ema_list() - Generate and return all
EMA beacon templates. Drivers must call ieee80211_beacon_free_ema_list()
to free the memory. No change in the prototype for the existing API,
ieee80211_beacon_get_template(), which should be used for non-EMA AP.

- ieee80211_beacon_get_template_ema_index() - Generate a beacon which
includes the multiple BSSID element at the given index. Drivers can use
this function in a loop until NULL is returned which indicates end of
available MBSSID elements.

- ieee80211_beacon_free_ema_list() - free the memory allocated for the
list of EMA beacon templates.

Modify existing functions ieee80211_beacon_get_ap(),
ieee80211_get_mbssid_beacon_len() and ieee80211_beacon_add_mbssid()
to accept a new parameter for EMA index.

Signed-off-by: Aloka Dixit <quic_alokad@quicinc.com>
Co-developed-by: John Crispin <john@phrozen.org>
Signed-off-by: John Crispin <john@phrozen.org>
Link: https://lore.kernel.org/r/20221206005040.3177-2-quic_alokad@quicinc.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index fcfe3e9aff3d..679421d37a42 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -5286,6 +5286,74 @@ ieee80211_beacon_get_template(struct ieee80211_hw *hw,
 			      unsigned int link_id);
 
 /**
+ * ieee80211_beacon_get_template_ema_index - EMA beacon template generation
+ * @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.
+ * @link_id: the link id to which the beacon belongs (or 0 for a non-MLD AP).
+ * @ema_index: index of the beacon in the EMA set.
+ *
+ * This function follows the same rules as ieee80211_beacon_get_template()
+ * but returns a beacon template which includes multiple BSSID element at the
+ * requested index.
+ *
+ * Return: The beacon template. %NULL indicates the end of EMA templates.
+ */
+struct sk_buff *
+ieee80211_beacon_get_template_ema_index(struct ieee80211_hw *hw,
+					struct ieee80211_vif *vif,
+					struct ieee80211_mutable_offsets *offs,
+					unsigned int link_id, u8 ema_index);
+
+/**
+ * struct ieee80211_ema_beacons - List of EMA beacons
+ * @cnt: count of EMA beacons.
+ *
+ * @bcn: array of EMA beacons.
+ * @bcn.skb: the skb containing this specific beacon
+ * @bcn.offs: &struct ieee80211_mutable_offsets pointer to struct that will
+ *	receive the offsets that may be updated by the driver.
+ */
+struct ieee80211_ema_beacons {
+	u8 cnt;
+	struct {
+		struct sk_buff *skb;
+		struct ieee80211_mutable_offsets offs;
+	} bcn[];
+};
+
+/**
+ * ieee80211_beacon_get_template_ema_list - EMA beacon template generation
+ * @hw: pointer obtained from ieee80211_alloc_hw().
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
+ * @link_id: the link id to which the beacon belongs (or 0 for a non-MLD AP)
+ *
+ * This function follows the same rules as ieee80211_beacon_get_template()
+ * but allocates and returns a pointer to list of all beacon templates required
+ * to cover all profiles in the multiple BSSID set. Each template includes only
+ * one multiple BSSID element.
+ *
+ * Driver must call ieee80211_beacon_free_ema_list() to free the memory.
+ *
+ * Return: EMA beacon templates of type struct ieee80211_ema_beacons *.
+ *	%NULL on error.
+ */
+struct ieee80211_ema_beacons *
+ieee80211_beacon_get_template_ema_list(struct ieee80211_hw *hw,
+				       struct ieee80211_vif *vif,
+				       unsigned int link_id);
+
+/**
+ * ieee80211_beacon_free_ema_list - free an EMA beacon template list
+ * @ema_beacons: list of EMA beacons of type &struct ieee80211_ema_beacons pointers.
+ *
+ * This function will free a list previously acquired by calling
+ * ieee80211_beacon_get_template_ema_list()
+ */
+void ieee80211_beacon_free_ema_list(struct ieee80211_ema_beacons *ema_beacons);
+
+/**
  * ieee80211_beacon_get_tim - beacon generation function
  * @hw: pointer obtained from ieee80211_alloc_hw().
  * @vif: &struct ieee80211_vif pointer from the add_interface callback.