ath10k: cleanup RX decap handling

Simplify decapping code and make it easier to
understand.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

diff --git a/drivers/net/wireless/ath/ath10k/htt_rx.c b/drivers/net/wireless/ath/ath10k/htt_rx.c
index 617df96..cdb4e6d 100644 (file)
--- a/drivers/net/wireless/ath/ath10k/htt_rx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_rx.c
@@ -669,11 +669,16 @@ static void ath10k_htt_rx_amsdu(struct ath10k_htt *htt,
 
                switch (fmt) {
                case RX_MSDU_DECAP_RAW:
+                       /* remove trailing FCS */
                        skb_trim(skb, skb->len - FCS_LEN);
                        break;
                case RX_MSDU_DECAP_NATIVE_WIFI:
+                       /* nothing to do */
                        break;
                case RX_MSDU_DECAP_ETHERNET2_DIX:
+                       /* strip ethernet header and insert decapped 802.11
+                        * header, amsdu subframe header and rfc1042 header */
+
                        len = 0;
                        len += sizeof(struct rfc1042_hdr);
                        len += sizeof(struct amsdu_subframe_hdr);
@@ -683,6 +688,8 @@ static void ath10k_htt_rx_amsdu(struct ath10k_htt *htt,
                        memcpy(skb_push(skb, hdr_len), hdr, hdr_len);
                        break;
                case RX_MSDU_DECAP_8023_SNAP_LLC:
+                       /* insert decapped 802.11 header making a singly
+                        * A-MSDU */
                        memcpy(skb_push(skb, hdr_len), hdr, hdr_len);
                        break;
                }
@@ -706,6 +713,8 @@ static void ath10k_htt_rx_msdu(struct ath10k_htt *htt, struct htt_rx_info *info)
        struct ieee80211_hdr *hdr;
        enum rx_msdu_decap_format fmt;
        enum htt_rx_mpdu_encrypt_type enctype;
+       int hdr_len;
+       void *rfc1042;
 
        /* This shouldn't happen. If it does than it may be a FW bug. */
        if (skb->next) {
@@ -719,46 +728,39 @@ static void ath10k_htt_rx_msdu(struct ath10k_htt *htt, struct htt_rx_info *info)
                        RX_MSDU_START_INFO1_DECAP_FORMAT);
        enctype = MS(__le32_to_cpu(rxd->mpdu_start.info0),
                        RX_MPDU_START_INFO0_ENCRYPT_TYPE);
-       hdr = (void *)skb->data - RX_HTT_HDR_STATUS_LEN;
+       hdr = (struct ieee80211_hdr *)rxd->rx_hdr_status;
+       hdr_len = ieee80211_hdrlen(hdr->frame_control);
 
        skb->ip_summed = ath10k_htt_rx_get_csum_state(skb);
 
        switch (fmt) {
        case RX_MSDU_DECAP_RAW:
                /* remove trailing FCS */
-               skb_trim(skb, skb->len - 4);
+               skb_trim(skb, skb->len - FCS_LEN);
                break;
        case RX_MSDU_DECAP_NATIVE_WIFI:
                /* nothing to do here */
                break;
        case RX_MSDU_DECAP_ETHERNET2_DIX:
-               /* macaddr[6] + macaddr[6] + ethertype[2] */
-               skb_pull(skb, 6 + 6 + 2);
-               break;
-       case RX_MSDU_DECAP_8023_SNAP_LLC:
-               /* macaddr[6] + macaddr[6] + len[2] */
-               /* we don't need this for non-A-MSDU */
-               skb_pull(skb, 6 + 6 + 2);
-               break;
-       }
-
-       if (fmt == RX_MSDU_DECAP_ETHERNET2_DIX) {
-               void *llc;
-               int llclen;
+               /* strip ethernet header and insert decapped 802.11 header and
+                * rfc1042 header */
 
-               llclen = 8;
-               llc  = hdr;
-               llc += roundup(ieee80211_hdrlen(hdr->frame_control), 4);
-               llc += roundup(ath10k_htt_rx_crypto_param_len(enctype), 4);
+               rfc1042 = hdr;
+               rfc1042 += roundup(hdr_len, 4);
+               rfc1042 += roundup(ath10k_htt_rx_crypto_param_len(enctype), 4);
 
-               skb_push(skb, llclen);
-               memcpy(skb->data, llc, llclen);
-       }
+               skb_pull(skb, sizeof(struct ethhdr));
+               memcpy(skb_push(skb, sizeof(struct rfc1042_hdr)),
+                      rfc1042, sizeof(struct rfc1042_hdr));
+               memcpy(skb_push(skb, hdr_len), hdr, hdr_len);
+               break;
+       case RX_MSDU_DECAP_8023_SNAP_LLC:
+               /* remove A-MSDU subframe header and insert
+                * decapped 802.11 header. rfc1042 header is already there */
 
-       if (fmt >= RX_MSDU_DECAP_ETHERNET2_DIX) {
-               int len = ieee80211_hdrlen(hdr->frame_control);
-               skb_push(skb, len);
-               memcpy(skb->data, hdr, len);
+               skb_pull(skb, sizeof(struct amsdu_subframe_hdr));
+               memcpy(skb_push(skb, hdr_len), hdr, hdr_len);
+               break;
        }
 
        info->skb = skb;