wifi: cfg80211: Add support for dynamic addition/removal of links

Add support for requesting dynamic addition/removal of links to the
current MLO association.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250102161730.cef23352f2a2.I79c849974c494cb1cbf9e1b22a5d2d37395ff5ac@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

2 files changed, 55 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 8a38d66be2c9..d4b4cabac029 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4596,6 +4596,15 @@ struct mgmt_frame_regs {
  * @set_ttlm: set the TID to link mapping.
  * @get_radio_mask: get bitmask of radios in use.
  *	(invoked with the wiphy mutex held)
+ * @assoc_ml_reconf: Request a non-AP MLO connection to perform ML
+ *	reconfiguration, i.e., add and/or remove links to/from the
+ *	association using ML reconfiguration action frames. Successfully added
+ *	links will be added to the set of valid links. Successfully removed
+ *	links will be removed from the set of valid links. The driver must
+ *	indicate removed links by calling cfg80211_links_removed() and added
+ *	links by calling cfg80211_mlo_reconf_add_done(). When calling
+ *	cfg80211_mlo_reconf_add_done() the bss pointer must be given for each
+ *	link for which MLO reconfiguration 'add' operation was requested.
  */
 struct cfg80211_ops {
 	int	(*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow);
@@ -4959,6 +4968,9 @@ struct cfg80211_ops {
 	int	(*set_ttlm)(struct wiphy *wiphy, struct net_device *dev,
 			    struct cfg80211_ttlm_params *params);
 	u32	(*get_radio_mask)(struct wiphy *wiphy, struct net_device *dev);
+	int     (*assoc_ml_reconf)(struct wiphy *wiphy, struct net_device *dev,
+				   struct cfg80211_assoc_link *add_links,
+				   u16 rem_links);
 };
 
 /*
@@ -9717,6 +9729,39 @@ static inline int cfg80211_color_change_notify(struct net_device *dev,
 void cfg80211_links_removed(struct net_device *dev, u16 link_mask);
 
 /**
+ * struct cfg80211_mlo_reconf_done_data - MLO reconfiguration data
+ * @buf: MLO Reconfiguration Response frame (header + body)
+ * @len: length of the frame data
+ * @added_links: BIT mask of links successfully added to the association
+ * @links: per-link information indexed by link ID
+ * @links.bss: the BSS that MLO reconfiguration was requested for, ownership of
+ *      the pointer moves to cfg80211 in the call to
+ *      cfg80211_mlo_reconf_add_done().
+ *
+ * The BSS pointer must be set for each link for which 'add' operation was
+ * requested in the assoc_ml_reconf callback.
+ */
+struct cfg80211_mlo_reconf_done_data {
+	const u8 *buf;
+	size_t len;
+	u16 added_links;
+	struct {
+		struct cfg80211_bss *bss;
+	} links[IEEE80211_MLD_MAX_NUM_LINKS];
+};
+
+/**
+ * cfg80211_mlo_reconf_add_done - Notify about MLO reconfiguration result
+ * @dev: network device.
+ * @data: MLO reconfiguration done data, &struct cfg80211_mlo_reconf_done_data
+ *
+ * Inform cfg80211 and the userspace that processing of ML reconfiguration
+ * request to add links to the association is done.
+ */
+void cfg80211_mlo_reconf_add_done(struct net_device *dev,
+				  struct cfg80211_mlo_reconf_done_data *data);
+
+/**
  * cfg80211_schedule_channels_check - schedule regulatory check if needed
  * @wdev: the wireless device to check
  *
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index ee1cf19803ea..f900d7cc42bc 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1329,6 +1329,9 @@
  *      %NL80211_ATTR_MLO_TTLM_ULINK attributes are used to specify the
  *      TID to Link mapping for downlink/uplink traffic.
  *
+ * @NL80211_CMD_ASSOC_MLO_RECONF: For a non-AP MLD station, request to
+ *      add/remove links to/from the association.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -1586,6 +1589,8 @@ enum nl80211_commands {
 
 	NL80211_CMD_SET_TID_TO_LINK_MAPPING,
 
+	NL80211_CMD_ASSOC_MLO_RECONF,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */
@@ -2877,6 +2882,9 @@ enum nl80211_commands {
  *	This can be used to provide a list of selectors that are implemented
  *	by the supplicant. If not given, support for SAE_H2E is assumed.
  *
+ * @NL80211_ATTR_MLO_RECONF_REM_LINKS: (u16) A bitmask of the links requested
+ *      to be removed from the MLO association.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3429,6 +3437,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_SUPPORTED_SELECTORS,
 
+	NL80211_ATTR_MLO_RECONF_REM_LINKS,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,