wifi: mac80211: add sta link addition/removal

Add the necessary infrastructure, including a new driver
method, to add/remove links to/from a station. To do this,
refactor the link alloc/free a bit, splitting that so we
can do it without linking them, to handle failures better.

Note that a station entry must be created representing an
MLD or a non-MLD STA, it cannot change between the two.
When representing an MLD, the 'deflink' is used for the
first link, which might be removed later, in which case
the memory isn't reused.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 1bea225c0d4d..1bc9d1d9769a 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2150,7 +2150,6 @@ struct ieee80211_link_sta {
  * @max_tid_amsdu_len: Maximum A-MSDU size in bytes for this TID
  * @txq: per-TID data TX queues (if driver uses the TXQ abstraction); note that
  *	the last entry (%IEEE80211_NUM_TIDS) is used for non-data frames
- * @multi_link_sta: Identifies if this sta is a MLD STA
  * @deflink: This holds the default link STA information, for non MLO STA all link
  *	specific STA information is accessed through @deflink or through
  *	link[0] which points to address of @deflink. For MLO Link STA
@@ -2162,6 +2161,7 @@ struct ieee80211_link_sta {
  *	@deflink address and remaining would be allocated and the address
  *	would be assigned to link[link_id] where link_id is the id assigned
  *	by the AP.
+ * @valid_links: bitmap of valid links, or 0 for non-MLO
  */
 struct ieee80211_sta {
 	u8 addr[ETH_ALEN];
@@ -2199,7 +2199,7 @@ struct ieee80211_sta {
 
 	struct ieee80211_txq *txq[IEEE80211_NUM_TIDS + 1];
 
-	bool multi_link_sta;
+	u16 valid_links;
 	struct ieee80211_link_sta deflink;
 	struct ieee80211_link_sta *link[IEEE80211_MLD_MAX_NUM_LINKS];
 
@@ -4048,6 +4048,11 @@ struct ieee80211_prep_tx_info {
  *	The @old[] array contains pointers to the old bss_conf structures
  *	that were already removed, in case they're needed.
  *	This callback can sleep.
+ * @change_sta_links: Change the valid links of a station, similar to
+ *	@change_vif_links. This callback can sleep.
+ *	Note that a sta can also be inserted or removed with valid links,
+ *	i.e. passed to @sta_add/@sta_state with sta->valid_links not zero.
+ *	In fact, cannot change from having valid_links and not having them.
  */
 struct ieee80211_ops {
 	void (*tx)(struct ieee80211_hw *hw,
@@ -4395,6 +4400,10 @@ struct ieee80211_ops {
 				struct ieee80211_vif *vif,
 				u16 old_links, u16 new_links,
 				struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS]);
+	int (*change_sta_links)(struct ieee80211_hw *hw,
+				struct ieee80211_vif *vif,
+				struct ieee80211_sta *sta,
+				u16 old_links, u16 new_links);
 };
 
 /**