2023-09-20 19:37:27

by Greenman, Gregory

[permalink] [raw]
Subject: [PATCH v2 14/18] wifi: mac80211: support handling of advertised TID-to-link mapping

From: Ayala Beker <[email protected]>

Support handling of advertised TID-to-link mapping elements received
in a beacon.
These elements are used by AP MLD to disable specific links and force
all clients to stop using these links.
By default if no TID-to-link mapping is advertised, all TIDs shall be
mapped to all links.

Signed-off-by: Ayala Beker <[email protected]>
Signed-off-by: Gregory Greenman <[email protected]>
---
net/mac80211/ieee80211_i.h | 15 +++
net/mac80211/mlme.c | 196 +++++++++++++++++++++++++++++++++++++
2 files changed, 211 insertions(+)

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 3209c7c11207..eb459a6a76f5 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -467,6 +467,17 @@ struct ieee80211_sta_tx_tspec {
bool downgraded;
};

+/* Advertised TID-to-link mapping info */
+struct ieee80211_adv_ttlm_info {
+ /* time in TUs at which the new mapping is established, or 0 if there is
+ * no planned advertised TID-to-link mapping
+ */
+ u16 switch_time;
+ u32 duration; /* duration of the planned T2L map in TUs */
+ u16 map; /* map of usable links for all TIDs */
+ bool active; /* whether the advertised mapping is active or not */
+};
+
DECLARE_EWMA(beacon_signal, 4, 4)

struct ieee80211_if_managed {
@@ -560,6 +571,10 @@ struct ieee80211_if_managed {

struct wiphy_delayed_work ml_reconf_work;
u16 removed_links;
+
+ /* TID-to-link mapping support */
+ struct wiphy_delayed_work ttlm_work;
+ struct ieee80211_adv_ttlm_info ttlm_info;
};

struct ieee80211_if_ibss {
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 091ec0753df7..c1619bb2b11d 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -3053,6 +3053,9 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
memset(sdata->vif.bss_conf.tx_pwr_env, 0,
sizeof(sdata->vif.bss_conf.tx_pwr_env));

+ memset(&sdata->u.mgd.ttlm_info, 0,
+ sizeof(sdata->u.mgd.ttlm_info));
+ wiphy_delayed_work_cancel(sdata->local->hw.wiphy, &ifmgd->ttlm_work);
ieee80211_vif_set_links(sdata, 0, 0);
}

@@ -5844,6 +5847,194 @@ static void ieee80211_ml_reconfiguration(struct ieee80211_sub_if_data *sdata,
TU_TO_JIFFIES(delay));
}

+static void ieee80211_tid_to_link_map_work(struct wiphy *wiphy,
+ struct wiphy_work *work)
+{
+ u16 new_active_links, new_dormant_links;
+ struct ieee80211_sub_if_data *sdata =
+ container_of(work, struct ieee80211_sub_if_data,
+ u.mgd.ttlm_work.work);
+ int ret;
+
+ new_active_links = sdata->u.mgd.ttlm_info.map &
+ sdata->vif.valid_links;
+ new_dormant_links = ~sdata->u.mgd.ttlm_info.map &
+ sdata->vif.valid_links;
+ if (!new_active_links) {
+ ieee80211_disconnect(&sdata->vif, false);
+ return;
+ }
+
+ ieee80211_vif_set_links(sdata, sdata->vif.valid_links, 0);
+ new_active_links = BIT(ffs(new_active_links) - 1);
+ ieee80211_set_active_links(&sdata->vif, new_active_links);
+
+ ret = ieee80211_vif_set_links(sdata, sdata->vif.valid_links,
+ new_dormant_links);
+
+ sdata->u.mgd.ttlm_info.active = true;
+ sdata->u.mgd.ttlm_info.switch_time = 0;
+
+ if (!ret)
+ ieee80211_vif_cfg_change_notify(sdata,
+ BSS_CHANGED_MLD_VALID_LINKS);
+}
+
+static u16 ieee80211_get_ttlm(u8 bm_size, u8 *data)
+{
+ if (bm_size == 1)
+ return *data;
+ else
+ return get_unaligned_le16(data);
+}
+
+static int
+ieee80211_parse_adv_t2l(struct ieee80211_sub_if_data *sdata,
+ const struct ieee80211_ttlm_elem *ttlm,
+ struct ieee80211_adv_ttlm_info *ttlm_info)
+{
+ /* The element size was already validated in
+ * ieee80211_tid_to_link_map_size_ok()
+ */
+ u8 control, link_map_presence, map_size, tid;
+ u8 *pos;
+
+ memset(ttlm_info, 0, sizeof(*ttlm_info));
+ pos = (void *)ttlm->optional;
+ control = ttlm->control;
+
+ if ((control & IEEE80211_TTLM_CONTROL_DEF_LINK_MAP) ||
+ !(control & IEEE80211_TTLM_CONTROL_SWITCH_TIME_PRESENT))
+ return 0;
+
+ if ((control & IEEE80211_TTLM_CONTROL_DIRECTION) !=
+ IEEE80211_TTLM_DIRECTION_BOTH) {
+ sdata_info(sdata, "Invalid advertised T2L map direction\n");
+ return -EINVAL;
+ }
+
+ link_map_presence = *pos;
+ pos++;
+
+ ttlm_info->switch_time = get_unaligned_le16(pos);
+ pos += 2;
+
+ if (control & IEEE80211_TTLM_CONTROL_EXPECTED_DUR_PRESENT) {
+ ttlm_info->duration = pos[0] | pos[1] << 8 | pos[2] << 16;
+ pos += 3;
+ }
+
+ if (control & IEEE80211_TTLM_CONTROL_LINK_MAP_SIZE)
+ map_size = 1;
+ else
+ map_size = 2;
+
+ /* According to Draft P802.11be_D3.0 clause 35.3.7.1.7, an AP MLD shall
+ * not advertise a TID-to-link mapping that does not map all TIDs to the
+ * same link set, reject frame if not all links have mapping
+ */
+ if (link_map_presence != 0xff) {
+ sdata_info(sdata,
+ "Invalid advertised T2L mapping presence indicator\n");
+ return -EINVAL;
+ }
+
+ ttlm_info->map = ieee80211_get_ttlm(map_size, pos);
+ if (!ttlm_info->map) {
+ sdata_info(sdata,
+ "Invalid advertised T2L map for TID 0\n");
+ return -EINVAL;
+ }
+
+ pos += map_size;
+
+ for (tid = 1; tid < 8; tid++) {
+ u16 map = ieee80211_get_ttlm(map_size, pos);
+
+ if (map != ttlm_info->map) {
+ sdata_info(sdata, "Invalid advertised T2L map for tid %d\n",
+ tid);
+ return -EINVAL;
+ }
+
+ pos += map_size;
+ }
+ return 0;
+}
+
+static void ieee80211_process_adv_ttlm(struct ieee80211_sub_if_data *sdata,
+ struct ieee802_11_elems *elems,
+ u64 beacon_ts)
+{
+ u8 i;
+ int ret;
+
+ if (!ieee80211_vif_is_mld(&sdata->vif))
+ return;
+
+ if (!elems->ttlm_num) {
+ if (sdata->u.mgd.ttlm_info.switch_time) {
+ /* if a planned TID-to-link mapping was cancelled -
+ * abort it
+ */
+ wiphy_delayed_work_cancel(sdata->local->hw.wiphy,
+ &sdata->u.mgd.ttlm_work);
+ } else if (sdata->u.mgd.ttlm_info.active) {
+ /* if no TID-to-link element, set to default mapping in
+ * which all TIDs are mapped to all setup links
+ */
+ ret = ieee80211_vif_set_links(sdata,
+ sdata->vif.valid_links,
+ 0);
+ if (ret) {
+ sdata_info(sdata, "Failed setting valid/dormant links\n");
+ return;
+ }
+ ieee80211_vif_cfg_change_notify(sdata,
+ BSS_CHANGED_MLD_VALID_LINKS);
+ }
+ memset(&sdata->u.mgd.ttlm_info, 0,
+ sizeof(sdata->u.mgd.ttlm_info));
+ return;
+ }
+
+ for (i = 0; i < elems->ttlm_num; i++) {
+ struct ieee80211_adv_ttlm_info ttlm_info;
+ u32 res;
+
+ res = ieee80211_parse_adv_t2l(sdata, elems->ttlm[i],
+ &ttlm_info);
+
+ if (res) {
+ __ieee80211_disconnect(sdata);
+ return;
+ }
+
+ if (ttlm_info.switch_time) {
+ u32 st_us, delay = 0;
+ u32 ts_l26 = beacon_ts & GENMASK(25, 0);
+
+ /* The t2l map switch time is indicated with a partial
+ * TSF value, convert it to TSF and calc the delay
+ * to the start time.
+ */
+ st_us = ieee80211_tu_to_usec(ttlm_info.switch_time);
+ if (st_us > ts_l26)
+ delay = st_us - ts_l26;
+ else
+ continue;
+
+ sdata->u.mgd.ttlm_info = ttlm_info;
+ wiphy_delayed_work_cancel(sdata->local->hw.wiphy,
+ &sdata->u.mgd.ttlm_work);
+ wiphy_delayed_work_queue(sdata->local->hw.wiphy,
+ &sdata->u.mgd.ttlm_work,
+ usecs_to_jiffies(delay));
+ return;
+ }
+ }
+}
+
static void ieee80211_rx_mgmt_beacon(struct ieee80211_link_data *link,
struct ieee80211_hdr *hdr, size_t len,
struct ieee80211_rx_status *rx_status)
@@ -6167,6 +6358,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_link_data *link,
}

ieee80211_ml_reconfiguration(sdata, elems);
+ ieee80211_process_adv_ttlm(sdata, elems,
+ le64_to_cpu(mgmt->u.beacon.timestamp));

ieee80211_link_info_change_notify(sdata, link, changed);
free:
@@ -6789,6 +6982,8 @@ void ieee80211_sta_setup_sdata(struct ieee80211_sub_if_data *sdata)
timer_setup(&ifmgd->conn_mon_timer, ieee80211_sta_conn_mon_timer, 0);
wiphy_delayed_work_init(&ifmgd->tx_tspec_wk,
ieee80211_sta_handle_tspec_ac_params_wk);
+ wiphy_delayed_work_init(&ifmgd->ttlm_work,
+ ieee80211_tid_to_link_map_work);

ifmgd->flags = 0;
ifmgd->powersave = sdata->wdev.ps;
@@ -7863,6 +8058,7 @@ void ieee80211_mgd_stop(struct ieee80211_sub_if_data *sdata)
&ifmgd->tdls_peer_del_work);
wiphy_delayed_work_cancel(sdata->local->hw.wiphy,
&ifmgd->ml_reconf_work);
+ wiphy_delayed_work_cancel(sdata->local->hw.wiphy, &ifmgd->ttlm_work);

if (ifmgd->assoc_data)
ieee80211_destroy_assoc_data(sdata, ASSOC_TIMEOUT);
--
2.38.1