package/kernel/mac80211/patches/subsys/358-mac80211-add-NEED_ALIGNED4_SKBS-hw-flag.patch

   1 From: Janusz Dziedzic <janusz.dziedzic@tieto.com>
   2 Date: Fri, 19 Feb 2016 11:01:50 +0100
   3 Subject: [PATCH] mac80211: add NEED_ALIGNED4_SKBS hw flag
   4
   5 HW/driver should set NEED_ALIGNED4_SKBS flag in case
   6 require aligned skbs to four-byte boundaries.
   7 This affect only TX direction.
   8
   9 Padding is added after ieee80211_hdr, before IV/LLC.
  10
  11 Before we have to do memmove(hdrlen) twice in the
  12 dirver. Once before we pass this to HW and next
  13 in tx completion (to be sure monitor will report
  14 this tx frame correctly).
  15
  16 With this patch we can skip this memmove() and save CPU.
  17
  18 Currently this was tested with ath9k, both hw/sw crypt for
  19 wep/tkip/ccmp.
  20
  21 Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
  22 ---
  23
  24 Index: backports-v4.18-rc7/include/net/mac80211.h
  25 ===================================================================
  26 --- backports-v4.18-rc7.orig/include/net/mac80211.h
  27 +++ backports-v4.18-rc7/include/net/mac80211.h
  28 @@ -2084,6 +2084,9 @@ struct ieee80211_txq {
  29   * @IEEE80211_HW_DOESNT_SUPPORT_QOS_NDP: The driver (or firmware) doesn't
  30   *     support QoS NDP for AP probing - that's most likely a driver bug.
  31   *
  32 + * @IEEE80211_HW_NEEDS_ALIGNED4_SKBS: Driver need aligned skbs to four-byte.
  33 + *     Padding will be added after ieee80211_hdr, before IV/LLC.
  34 + *
  35   * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
  36   */
  37  enum ieee80211_hw_flags {
  38 @@ -2129,6 +2132,7 @@ enum ieee80211_hw_flags {
  39         IEEE80211_HW_SUPPORTS_TDLS_BUFFER_STA,
  40         IEEE80211_HW_DEAUTH_NEED_MGD_TX_PREP,
  41         IEEE80211_HW_DOESNT_SUPPORT_QOS_NDP,
  42 +       IEEE80211_HW_NEEDS_ALIGNED4_SKBS,
  43
  44         /* keep last, obviously */
  45         NUM_IEEE80211_HW_FLAGS
  46 Index: backports-v4.18-rc7/net/mac80211/debugfs.c
  47 ===================================================================
  48 --- backports-v4.18-rc7.orig/net/mac80211/debugfs.c
  49 +++ backports-v4.18-rc7/net/mac80211/debugfs.c
  50 @@ -214,6 +214,7 @@ static const char *hw_flag_names[] = {
  51         FLAG(SUPPORTS_TDLS_BUFFER_STA),
  52         FLAG(DEAUTH_NEED_MGD_TX_PREP),
  53         FLAG(DOESNT_SUPPORT_QOS_NDP),
  54 +       FLAG(NEEDS_ALIGNED4_SKBS),
  55  #undef FLAG
  56  };
  57
  58 Index: backports-v4.18-rc7/net/mac80211/ieee80211_i.h
  59 ===================================================================
  60 --- backports-v4.18-rc7.orig/net/mac80211/ieee80211_i.h
  61 +++ backports-v4.18-rc7/net/mac80211/ieee80211_i.h
  62 @@ -1550,6 +1550,29 @@ ieee80211_vif_get_num_mcast_if(struct ie
  63         return -1;
  64  }
  65
  66 +static inline unsigned int
  67 +ieee80211_hdr_padsize(struct ieee80211_hw *hw, unsigned int hdrlen)
  68 +{
  69 +       /*
  70 +        * While hdrlen is already aligned to two-byte boundaries,
  71 +        * simple check with & 2 will return correct padsize.
  72 +        */
  73 +       if (ieee80211_hw_check(hw, NEEDS_ALIGNED4_SKBS))
  74 +               return hdrlen & 2;
  75 +       return 0;
  76 +}
  77 +
  78 +static inline unsigned int
  79 +ieee80211_padded_hdrlen(struct ieee80211_hw *hw, __le16 fc)
  80 +{
  81 +       unsigned int hdrlen;
  82 +
  83 +       hdrlen = ieee80211_hdrlen(fc);
  84 +       hdrlen += ieee80211_hdr_padsize(hw, hdrlen);
  85 +
  86 +       return hdrlen;
  87 +}
  88 +
  89  u64 ieee80211_calculate_rx_timestamp(struct ieee80211_local *local,
  90                                      struct ieee80211_rx_status *status,
  91                                      unsigned int mpdu_len,
  92 Index: backports-v4.18-rc7/net/mac80211/sta_info.h
  93 ===================================================================
  94 --- backports-v4.18-rc7.orig/net/mac80211/sta_info.h
  95 +++ backports-v4.18-rc7/net/mac80211/sta_info.h
  96 @@ -301,7 +301,7 @@ struct ieee80211_fast_tx {
  97         u8 hdr_len;
  98         u8 sa_offs, da_offs, pn_offs;
  99         u8 band;
 100 -       u8 hdr[30 + 2 + IEEE80211_FAST_XMIT_MAX_IV +
 101 +       u8 hdr[30 + 2 + 2 + IEEE80211_FAST_XMIT_MAX_IV +
 102                sizeof(rfc1042_header)] __aligned(2);
 103
 104         struct rcu_head rcu_head;
 105 Index: backports-v4.18-rc7/net/mac80211/status.c
 106 ===================================================================
 107 --- backports-v4.18-rc7.orig/net/mac80211/status.c
 108 +++ backports-v4.18-rc7/net/mac80211/status.c
 109 @@ -653,9 +653,22 @@ void ieee80211_tx_monitor(struct ieee802
 110         struct sk_buff *skb2;
 111         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 112         struct ieee80211_sub_if_data *sdata;
 113 +       struct ieee80211_hdr *hdr = (void *)skb->data;
 114         struct net_device *prev_dev = NULL;
 115 +       unsigned int hdrlen, padsize;
 116         int rtap_len;
 117
 118 +       /* Remove padding if was added */
 119 +       if (ieee80211_hw_check(&local->hw, NEEDS_ALIGNED4_SKBS)) {
 120 +               hdrlen = ieee80211_hdrlen(hdr->frame_control);
 121 +               padsize = ieee80211_hdr_padsize(&local->hw, hdrlen);
 122 +
 123 +               if (padsize && skb->len > hdrlen + padsize) {
 124 +                       memmove(skb->data + padsize, skb->data, hdrlen);
 125 +                       skb_pull(skb, padsize);
 126 +               }
 127 +       }
 128 +
 129         /* send frame to monitor interfaces now */
 130         rtap_len = ieee80211_tx_radiotap_len(info);
 131         if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
 132 Index: backports-v4.18-rc7/net/mac80211/tkip.c
 133 ===================================================================
 134 --- backports-v4.18-rc7.orig/net/mac80211/tkip.c
 135 +++ backports-v4.18-rc7/net/mac80211/tkip.c
 136 @@ -201,10 +201,12 @@ void ieee80211_get_tkip_p2k(struct ieee8
 137  {
 138         struct ieee80211_key *key = (struct ieee80211_key *)
 139                         container_of(keyconf, struct ieee80211_key, conf);
 140 +       struct ieee80211_hw *hw = &key->local->hw;
 141         const u8 *tk = &key->conf.key[NL80211_TKIP_DATA_OFFSET_ENCR_KEY];
 142         struct tkip_ctx *ctx = &key->u.tkip.tx;
 143         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 144 -       const u8 *data = (u8 *)hdr + ieee80211_hdrlen(hdr->frame_control);
 145 +       const u8 *data = (u8 *)hdr + ieee80211_padded_hdrlen(hw,
 146 +                                                       hdr->frame_control);
 147         u32 iv32 = get_unaligned_le32(&data[4]);
 148         u16 iv16 = data[2] | (data[0] << 8);
 149
 150 Index: backports-v4.18-rc7/net/mac80211/tx.c
 151 ===================================================================
 152 --- backports-v4.18-rc7.orig/net/mac80211/tx.c
 153 +++ backports-v4.18-rc7/net/mac80211/tx.c
 154 @@ -1169,8 +1169,7 @@ ieee80211_tx_prepare(struct ieee80211_su
 155         info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
 156
 157         hdr = (struct ieee80211_hdr *) skb->data;
 158 -
 159 -       tx->hdrlen = ieee80211_hdrlen(hdr->frame_control);
 160 +       tx->hdrlen = ieee80211_padded_hdrlen(&local->hw, hdr->frame_control);
 161
 162         if (likely(sta)) {
 163                 if (!IS_ERR(sta))
 164 @@ -2200,7 +2199,7 @@ netdev_tx_t ieee80211_monitor_start_xmit
 165                 goto fail;
 166
 167         hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
 168 -       hdrlen = ieee80211_hdrlen(hdr->frame_control);
 169 +       hdrlen = ieee80211_padded_hdrlen(&local->hw, hdr->frame_control);
 170
 171         if (skb->len < len_rthdr + hdrlen)
 172                 goto fail;
 173 @@ -2418,7 +2417,7 @@ static struct sk_buff *ieee80211_build_h
 174         struct ieee80211_chanctx_conf *chanctx_conf;
 175         struct ieee80211_sub_if_data *ap_sdata;
 176         enum nl80211_band band;
 177 -       int ret;
 178 +       int padsize, ret;
 179
 180         if (IS_ERR(sta))
 181                 sta = NULL;
 182 @@ -2638,6 +2637,9 @@ static struct sk_buff *ieee80211_build_h
 183                 hdrlen += 2;
 184         }
 185
 186 +       /* Check aligned4 skb required */
 187 +       padsize = ieee80211_hdr_padsize(&sdata->local->hw, hdrlen);
 188 +
 189         /*
 190          * Drop unicast frames to unauthorised stations unless they are
 191          * EAPOL frames from the local station.
 192 @@ -2718,6 +2720,7 @@ static struct sk_buff *ieee80211_build_h
 193
 194         skb_pull(skb, skip_header_bytes);
 195         head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
 196 +       head_need += padsize;
 197
 198         /*
 199          * So we need to modify the skb header and hence need a copy of
 200 @@ -2750,6 +2753,9 @@ static struct sk_buff *ieee80211_build_h
 201                 memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
 202  #endif
 203
 204 +       if (padsize)
 205 +               memset(skb_push(skb, padsize), 0, padsize);
 206 +
 207         if (ieee80211_is_data_qos(fc)) {
 208                 __le16 *qos_control;
 209
 210 @@ -2925,6 +2931,9 @@ void ieee80211_check_fast_xmit(struct st
 211                 fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
 212         }
 213
 214 +       /* Check aligned4 skb required */
 215 +       build.hdr_len += ieee80211_hdr_padsize(&local->hw, build.hdr_len);
 216 +
 217         /* We store the key here so there's no point in using rcu_dereference()
 218          * but that's fine because the code that changes the pointers will call
 219          * this function after doing so. For a single CPU that would be enough,
 220 @@ -3513,7 +3522,7 @@ begin:
 221
 222                 if (tx.key &&
 223                     (tx.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV))
 224 -                       pn_offs = ieee80211_hdrlen(hdr->frame_control);
 225 +                       pn_offs = tx.hdrlen;
 226
 227                 ieee80211_xmit_fast_finish(sta->sdata, sta, pn_offs,
 228                                            tx.key, skb);
 229 Index: backports-v4.18-rc7/net/mac80211/util.c
 230 ===================================================================
 231 --- backports-v4.18-rc7.orig/net/mac80211/util.c
 232 +++ backports-v4.18-rc7/net/mac80211/util.c
 233 @@ -1274,6 +1274,7 @@ void ieee80211_send_auth(struct ieee8021
 234                          u32 tx_flags)
 235  {
 236         struct ieee80211_local *local = sdata->local;
 237 +       struct ieee80211_hw *hw = &local->hw;
 238         struct sk_buff *skb;
 239         struct ieee80211_mgmt *mgmt;
 240         unsigned int hdrlen;
 241 @@ -1300,7 +1301,7 @@ void ieee80211_send_auth(struct ieee8021
 242                 skb_put_data(skb, extra, extra_len);
 243
 244         if (auth_alg == WLAN_AUTH_SHARED_KEY && transaction == 3) {
 245 -               hdrlen = ieee80211_hdrlen(mgmt->frame_control);
 246 +               hdrlen = ieee80211_padded_hdrlen(hw, mgmt->frame_control);
 247                 mgmt->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 248                 err = ieee80211_wep_encrypt(local, skb, hdrlen, key,
 249                                             key_len, key_idx);