mac80211: introduce BSS color collision detection

Add ieee80211_rx_check_bss_color_collision routine in order to introduce
BSS color collision detection in mac80211 if it is not supported in HW/FW
(e.g. for mt7915 chipset).
Add IEEE80211_HW_DETECTS_COLOR_COLLISION flag to let the driver notify
BSS color collision detection is supported in HW/FW. Set this for ath11k
which apparently didn't need this code.

Tested-by: Peter Chiu <Chui-Hao.Chiu@mediatek.com>
Co-developed-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/a05eeeb1841a84560dc5aaec77894fcb69a54f27.1648204871.git.lorenzo@kernel.org
[clarify commit message a bit, move flag to mac80211]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index 175a4ae..49421d9 100644 (file)
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -8720,9 +8720,12 @@ static int __ath11k_mac_register(struct ath11k *ar)
 
        wiphy_ext_feature_set(ar->hw->wiphy, NL80211_EXT_FEATURE_CQM_RSSI_LIST);
        wiphy_ext_feature_set(ar->hw->wiphy, NL80211_EXT_FEATURE_STA_TX_PWR);
-       if (test_bit(WMI_TLV_SERVICE_BSS_COLOR_OFFLOAD, ar->ab->wmi_ab.svc_map))
+       if (test_bit(WMI_TLV_SERVICE_BSS_COLOR_OFFLOAD,
+                    ar->ab->wmi_ab.svc_map)) {
                wiphy_ext_feature_set(ar->hw->wiphy,
                                      NL80211_EXT_FEATURE_BSS_COLOR);
+               ieee80211_hw_set(ar->hw, DETECTS_COLOR_COLLISION);
+       }
 
        ar->hw->wiphy->cipher_suites = cipher_suites;
        ar->hw->wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index db992f7..0943b26 100644 (file)
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2434,6 +2434,9 @@ struct ieee80211_txq {
  *     usage and 802.11 frames with %RX_FLAG_ONLY_MONITOR set for monitor to
  *     the stack.
  *
+ * @IEEE80211_HW_DETECTS_COLOR_COLLISION: HW/driver has support for BSS color
+ *     collision detection and doesn't need it in software.
+ *
  * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
  */
 enum ieee80211_hw_flags {
@@ -2489,6 +2492,7 @@ enum ieee80211_hw_flags {
        IEEE80211_HW_SUPPORTS_TX_ENCAP_OFFLOAD,
        IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD,
        IEEE80211_HW_SUPPORTS_CONC_MON_RX_DECAP,
+       IEEE80211_HW_DETECTS_COLOR_COLLISION,
 
        /* keep last, obviously */
        NUM_IEEE80211_HW_FLAGS

diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index f4c9a92..1fe43b2 100644 (file)
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -504,6 +504,7 @@ static const char *hw_flag_names[] = {
        FLAG(SUPPORTS_TX_ENCAP_OFFLOAD),
        FLAG(SUPPORTS_RX_DECAP_OFFLOAD),
        FLAG(SUPPORTS_CONC_MON_RX_DECAP),
+       FLAG(DETECTS_COLOR_COLLISION),
 #undef FLAG
 };
 

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index beb6b92..03ee1d9 100644 (file)
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -3178,6 +3178,49 @@ static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
        ieee80211_tx_skb(sdata, skb);
 }
 
+static void
+ieee80211_rx_check_bss_color_collision(struct ieee80211_rx_data *rx)
+{
+       struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
+       const struct element *ie;
+       size_t baselen;
+
+       if (!wiphy_ext_feature_isset(rx->local->hw.wiphy,
+                                    NL80211_EXT_FEATURE_BSS_COLOR))
+               return;
+
+       if (ieee80211_hw_check(&rx->local->hw, DETECTS_COLOR_COLLISION))
+               return;
+
+       if (rx->sdata->vif.csa_active)
+               return;
+
+       baselen = mgmt->u.beacon.variable - rx->skb->data;
+       if (baselen > rx->skb->len)
+               return;
+
+       ie = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION,
+                                   mgmt->u.beacon.variable,
+                                   rx->skb->len - baselen);
+       if (ie && ie->datalen >= sizeof(struct ieee80211_he_operation) &&
+           ie->datalen >= ieee80211_he_oper_size(ie->data + 1)) {
+               struct ieee80211_bss_conf *bss_conf = &rx->sdata->vif.bss_conf;
+               const struct ieee80211_he_operation *he_oper;
+               u8 color;
+
+               he_oper = (void *)(ie->data + 1);
+               if (le32_get_bits(he_oper->he_oper_params,
+                                 IEEE80211_HE_OPERATION_BSS_COLOR_DISABLED))
+                       return;
+
+               color = le32_get_bits(he_oper->he_oper_params,
+                                     IEEE80211_HE_OPERATION_BSS_COLOR_MASK);
+               if (color == bss_conf->he_bss_color.color)
+                       ieeee80211_obss_color_collision_notify(&rx->sdata->vif,
+                                                              BIT_ULL(color));
+       }
+}
+
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
 {
@@ -3203,6 +3246,9 @@ ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
            !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
                int sig = 0;
 
+               /* sw bss color collision detection */
+               ieee80211_rx_check_bss_color_collision(rx);
+
                if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
                    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
                        sig = status->signal;