wifi: mac80211_hwsim: fix TX link selection

Now that we have a pointer to the TX STA even when it's
not authenticated/... yet, fix the TX link selection in
hwsim to select only among the valid links for the STA,
requiring a STA pointer here. Also implement a simple
round-robin between links to make life more interesting.

While at it, also consider A3 when translating to link
addresses.

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

diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index 36b8c95150aef59e5fdf25f66d1af7facc9e2635..934939aa5fb6bd293217e116aa70573d9f3f9446 100644 (file)
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -228,6 +228,7 @@ static inline void hwsim_clear_magic(struct ieee80211_vif *vif)
 
 struct hwsim_sta_priv {
        u32 magic;
+       unsigned int last_link;
 };
 
 #define HWSIM_STA_MAGIC        0x6d537749
@@ -1706,30 +1707,48 @@ mac80211_hwsim_select_tx_link(struct mac80211_hwsim_data *data,
                              struct ieee80211_sta *sta,
                              struct ieee80211_hdr *hdr)
 {
+       struct hwsim_sta_priv *sp = (void *)sta->drv_priv;
        int i;
 
+       if (!vif->valid_links)
+               return &vif->bss_conf;
+
+       /* FIXME: handle multicast TX properly */
+       if (is_multicast_ether_addr(hdr->addr1) || WARN_ON_ONCE(!sta)) {
+               unsigned int first_link = ffs(vif->valid_links) - 1;
+
+               return rcu_dereference(vif->link_conf[first_link]);
+       }
+
+       if (WARN_ON_ONCE(!sta->valid_links))
+               return &vif->bss_conf;
+
        for (i = 0; i < ARRAY_SIZE(vif->link_conf); i++) {
                struct ieee80211_link_sta *link_sta = NULL;
                struct ieee80211_bss_conf *bss_conf;
+               unsigned int link_id;
+
+               /* round-robin the available link IDs */
+               link_id = (sp->last_link + i + 1) % ARRAY_SIZE(vif->link_conf);
 
-               bss_conf = rcu_dereference(vif->link_conf[i]);
-               if (!bss_conf)
+               link_sta = rcu_dereference(sta->link[link_id]);
+               if (!link_sta)
                        continue;
 
-               if (sta) {
-                       link_sta = rcu_dereference(sta->link[i]);
-                       if (!link_sta)
-                               continue;
-               }
+               bss_conf = rcu_dereference(vif->link_conf[link_id]);
+               if (WARN_ON_ONCE(!bss_conf))
+                       continue;
 
-               if (!is_multicast_ether_addr(hdr->addr1)) {
-                       if (link_sta)
-                               ether_addr_copy(hdr->addr1, link_sta->addr);
-                       ether_addr_copy(hdr->addr2, bss_conf->addr);
-               } else {
-                       /* TODO: Handle multicast frames */
-               }
+               /* address translation to link addresses on TX */
+               ether_addr_copy(hdr->addr1, link_sta->addr);
+               ether_addr_copy(hdr->addr2, bss_conf->addr);
+               if (ether_addr_equal(hdr->addr3, sta->addr))
+                       ether_addr_copy(hdr->addr3, link_sta->addr);
+               else if (ether_addr_equal(hdr->addr3, vif->addr))
+                       ether_addr_copy(hdr->addr3, bss_conf->addr);
+               /* no need to look at A4, if present it's SA */
 
+               sp->last_link = link_id;
                return bss_conf;
        }