package/kernel/mac80211/patches/subsys/310-mac80211-split-mesh-fast-tx-cache-into-local-proxied.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Fri, 30 Jun 2023 13:11:51 +0200
   3 Subject: [PATCH] mac80211: split mesh fast tx cache into
   4  local/proxied/forwarded
   5
   6 Depending on the origin of the packets (and their SA), 802.11 + mesh headers
   7 could be filled in differently. In order to properly deal with that, add a
   8 new field to the lookup key, indicating the type (local, proxied or
   9 forwarded). This can fix spurious packet drop issues that depend on the order
  10 in which nodes/hosts communicate with each other.
  11
  12 Signed-off-by: Felix Fietkau <nbd@nbd.name>
  13 ---
  14
  15 --- a/net/mac80211/mesh.c
  16 +++ b/net/mac80211/mesh.c
  17 @@ -765,6 +765,9 @@ bool ieee80211_mesh_xmit_fast(struct iee
  18                               struct sk_buff *skb, u32 ctrl_flags)
  19  {
  20         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  21 +       struct ieee80211_mesh_fast_tx_key key = {
  22 +               .type = MESH_FAST_TX_TYPE_LOCAL
  23 +       };
  24         struct ieee80211_mesh_fast_tx *entry;
  25         struct ieee80211s_hdr *meshhdr;
  26         u8 sa[ETH_ALEN] __aligned(2);
  27 @@ -800,7 +803,10 @@ bool ieee80211_mesh_xmit_fast(struct iee
  28                         return false;
  29         }
  30
  31 -       entry = mesh_fast_tx_get(sdata, skb->data);
  32 +       ether_addr_copy(key.addr, skb->data);
  33 +       if (!ether_addr_equal(skb->data + ETH_ALEN, sdata->vif.addr))
  34 +               key.type = MESH_FAST_TX_TYPE_PROXIED;
  35 +       entry = mesh_fast_tx_get(sdata, &key);
  36         if (!entry)
  37                 return false;
  38
  39 --- a/net/mac80211/mesh.h
  40 +++ b/net/mac80211/mesh.h
  41 @@ -134,9 +134,33 @@ struct mesh_path {
  42  #define MESH_FAST_TX_CACHE_TIMEOUT             8000 /* msecs */
  43
  44  /**
  45 + * enum ieee80211_mesh_fast_tx_type - cached mesh fast tx entry type
  46 + *
  47 + * @MESH_FAST_TX_TYPE_LOCAL: tx from the local vif address as SA
  48 + * @MESH_FAST_TX_TYPE_PROXIED: local tx with a different SA (e.g. bridged)
  49 + * @MESH_FAST_TX_TYPE_FORWARDED: forwarded from a different mesh point
  50 + */
  51 +enum ieee80211_mesh_fast_tx_type {
  52 +       MESH_FAST_TX_TYPE_LOCAL,
  53 +       MESH_FAST_TX_TYPE_PROXIED,
  54 +       MESH_FAST_TX_TYPE_FORWARDED,
  55 +};
  56 +
  57 +/**
  58 + * struct ieee80211_mesh_fast_tx_key - cached mesh fast tx entry key
  59 + *
  60 + * @addr: The Ethernet DA for this entry
  61 + * @type: cache entry type
  62 + */
  63 +struct ieee80211_mesh_fast_tx_key {
  64 +       u8 addr[ETH_ALEN] __aligned(2);
  65 +       enum ieee80211_mesh_fast_tx_type type;
  66 +};
  67 +
  68 +/**
  69   * struct ieee80211_mesh_fast_tx - cached mesh fast tx entry
  70   * @rhash: rhashtable pointer
  71 - * @addr_key: The Ethernet DA which is the key for this entry
  72 + * @key: the lookup key for this cache entry
  73   * @fast_tx: base fast_tx data
  74   * @hdr: cached mesh and rfc1042 headers
  75   * @hdrlen: length of mesh + rfc1042
  76 @@ -147,7 +171,7 @@ struct mesh_path {
  77   */
  78  struct ieee80211_mesh_fast_tx {
  79         struct rhash_head rhash;
  80 -       u8 addr_key[ETH_ALEN] __aligned(2);
  81 +       struct ieee80211_mesh_fast_tx_key key;
  82
  83         struct ieee80211_fast_tx fast_tx;
  84         u8 hdr[sizeof(struct ieee80211s_hdr) + sizeof(rfc1042_header)];
  85 @@ -333,7 +357,8 @@ void mesh_path_tx_root_frame(struct ieee
  86
  87  bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt);
  88  struct ieee80211_mesh_fast_tx *
  89 -mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata, const u8 *addr);
  90 +mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata,
  91 +                struct ieee80211_mesh_fast_tx_key *key);
  92  bool ieee80211_mesh_xmit_fast(struct ieee80211_sub_if_data *sdata,
  93                               struct sk_buff *skb, u32 ctrl_flags);
  94  void mesh_fast_tx_cache(struct ieee80211_sub_if_data *sdata,
  95 --- a/net/mac80211/mesh_pathtbl.c
  96 +++ b/net/mac80211/mesh_pathtbl.c
  97 @@ -36,8 +36,8 @@ static const struct rhashtable_params me
  98  static const struct rhashtable_params fast_tx_rht_params = {
  99         .nelem_hint = 10,
 100         .automatic_shrinking = true,
 101 -       .key_len = ETH_ALEN,
 102 -       .key_offset = offsetof(struct ieee80211_mesh_fast_tx, addr_key),
 103 +       .key_len = sizeof(struct ieee80211_mesh_fast_tx_key),
 104 +       .key_offset = offsetof(struct ieee80211_mesh_fast_tx, key),
 105         .head_offset = offsetof(struct ieee80211_mesh_fast_tx, rhash),
 106         .hashfn = mesh_table_hash,
 107  };
 108 @@ -426,20 +426,21 @@ static void mesh_fast_tx_entry_free(stru
 109  }
 110
 111  struct ieee80211_mesh_fast_tx *
 112 -mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata, const u8 *addr)
 113 +mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata,
 114 +                struct ieee80211_mesh_fast_tx_key *key)
 115  {
 116         struct ieee80211_mesh_fast_tx *entry;
 117         struct mesh_tx_cache *cache;
 118
 119         cache = &sdata->u.mesh.tx_cache;
 120 -       entry = rhashtable_lookup(&cache->rht, addr, fast_tx_rht_params);
 121 +       entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params);
 122         if (!entry)
 123                 return NULL;
 124
 125         if (!(entry->mpath->flags & MESH_PATH_ACTIVE) ||
 126             mpath_expired(entry->mpath)) {
 127                 spin_lock_bh(&cache->walk_lock);
 128 -               entry = rhashtable_lookup(&cache->rht, addr, fast_tx_rht_params);
 129 +               entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params);
 130                 if (entry)
 131                     mesh_fast_tx_entry_free(cache, entry);
 132                 spin_unlock_bh(&cache->walk_lock);
 133 @@ -484,18 +485,24 @@ void mesh_fast_tx_cache(struct ieee80211
 134         if (!sta)
 135                 return;
 136
 137 +       build.key.type = MESH_FAST_TX_TYPE_LOCAL;
 138         if ((meshhdr->flags & MESH_FLAGS_AE) == MESH_FLAGS_AE_A5_A6) {
 139                 /* This is required to keep the mppath alive */
 140                 mppath = mpp_path_lookup(sdata, meshhdr->eaddr1);
 141                 if (!mppath)
 142                         return;
 143                 build.mppath = mppath;
 144 +               if (!ether_addr_equal(meshhdr->eaddr2, sdata->vif.addr))
 145 +                       build.key.type = MESH_FAST_TX_TYPE_PROXIED;
 146         } else if (ieee80211_has_a4(hdr->frame_control)) {
 147                 mppath = mpath;
 148         } else {
 149                 return;
 150         }
 151
 152 +       if (!ether_addr_equal(hdr->addr4, sdata->vif.addr))
 153 +               build.key.type = MESH_FAST_TX_TYPE_FORWARDED;
 154 +
 155         /* rate limit, in case fast xmit can't be enabled */
 156         if (mppath->fast_tx_check == jiffies)
 157                 return;
 158 @@ -542,7 +549,7 @@ void mesh_fast_tx_cache(struct ieee80211
 159                 }
 160         }
 161
 162 -       memcpy(build.addr_key, mppath->dst, ETH_ALEN);
 163 +       memcpy(build.key.addr, mppath->dst, ETH_ALEN);
 164         build.timestamp = jiffies;
 165         build.fast_tx.band = info->band;
 166         build.fast_tx.da_offs = offsetof(struct ieee80211_hdr, addr3);
 167 @@ -644,13 +651,19 @@ void mesh_fast_tx_flush_addr(struct ieee
 168                              const u8 *addr)
 169  {
 170         struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
 171 +       struct ieee80211_mesh_fast_tx_key key = {};
 172         struct ieee80211_mesh_fast_tx *entry;
 173 +       int i;
 174
 175 +       ether_addr_copy(key.addr, addr);
 176         cache = &sdata->u.mesh.tx_cache;
 177         spin_lock_bh(&cache->walk_lock);
 178 -       entry = rhashtable_lookup_fast(&cache->rht, addr, fast_tx_rht_params);
 179 -       if (entry)
 180 -               mesh_fast_tx_entry_free(cache, entry);
 181 +       for (i = MESH_FAST_TX_TYPE_LOCAL; i < MESH_FAST_TX_TYPE_FORWARDED; i++) {
 182 +               key.type = i;
 183 +               entry = rhashtable_lookup_fast(&cache->rht, &key, fast_tx_rht_params);
 184 +               if (entry)
 185 +                       mesh_fast_tx_entry_free(cache, entry);
 186 +       }
 187         spin_unlock_bh(&cache->walk_lock);
 188  }
 189
 190 --- a/net/mac80211/rx.c
 191 +++ b/net/mac80211/rx.c
 192 @@ -2726,7 +2726,10 @@ ieee80211_rx_mesh_fast_forward(struct ie
 193                                struct sk_buff *skb, int hdrlen)
 194  {
 195         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 196 -       struct ieee80211_mesh_fast_tx *entry = NULL;
 197 +       struct ieee80211_mesh_fast_tx_key key = {
 198 +               .type = MESH_FAST_TX_TYPE_FORWARDED
 199 +       };
 200 +       struct ieee80211_mesh_fast_tx *entry;
 201         struct ieee80211s_hdr *mesh_hdr;
 202         struct tid_ampdu_tx *tid_tx;
 203         struct sta_info *sta;
 204 @@ -2735,9 +2738,13 @@ ieee80211_rx_mesh_fast_forward(struct ie
 205
 206         mesh_hdr = (struct ieee80211s_hdr *)(skb->data + sizeof(eth));
 207         if ((mesh_hdr->flags & MESH_FLAGS_AE) == MESH_FLAGS_AE_A5_A6)
 208 -               entry = mesh_fast_tx_get(sdata, mesh_hdr->eaddr1);
 209 +               ether_addr_copy(key.addr, mesh_hdr->eaddr1);
 210         else if (!(mesh_hdr->flags & MESH_FLAGS_AE))
 211 -               entry = mesh_fast_tx_get(sdata, skb->data);
 212 +               ether_addr_copy(key.addr, skb->data);
 213 +       else
 214 +               return false;
 215 +
 216 +       entry = mesh_fast_tx_get(sdata, &key);
 217         if (!entry)
 218                 return false;
 219