Add A-MSDU Rx aggregation support.
To support IEEE 802.11n, we need to be able to process A-MSDU frames.
The present of the HT control field indicates it is A-MSDU frame.
This patch adds support to discover and process A-MSDU frames.
Signed-off-by: Mohamed Abbas <mabbas@xxxxxxxxxxxxxxx>
diff -Nupr wireless-dev/net/mac80211/ieee80211.c
wireless-dev-new/net/mac80211/ieee80211.c
--- wireless-dev/net/mac80211/ieee80211.c 2007-03-27 00:36:24.000000000
-0700
+++ wireless-dev-new/net/mac80211/ieee80211.c 2007-03-27
01:54:48.000000000 -0700
@@ -2446,6 +2446,143 @@ static inline int ieee80211_bssid_match(
}
+inline static unsigned int calc_pad_len(unsigned int len)
+{
+ return (4 - len % 4) % 4;
+}
+
+inline static int is_agg_frame(struct sk_buff *skb, u16 fc)
+{
+ u8 *p = skb->data + ieee80211_get_hdrlen(fc) - 2;
+
+ if (!(fc & IEEE80211_STYPE_QOS_DATA));
+ return 0;
+
+ if (*p & QOS_CONTROL_A_MSDU_PRESENT)
+ return 1;
+ else
+ return 0;
+}
+
+static ieee80211_txrx_result
+ieee80211_rx_h_data_agg(struct ieee80211_txrx_data *rx)
+{
+ struct net_device *dev = rx->dev;
+ struct ieee80211_local *local = rx->local;
+ u16 fc, hdrlen, ethertype;
+ u8 *payload;
+ struct sk_buff *skb = rx->skb, *skb2, *frame;
+ struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+ const struct ethhdr* eth;
+
+ fc = rx->fc;
+ if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
+ return TXRX_CONTINUE;
+
+ if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
+ return TXRX_DROP;
+
+ if (!is_agg_frame(skb, fc))
+ return TXRX_CONTINUE;
+
+ hdrlen = ieee80211_get_hdrlen(fc);
+
+ payload = skb->data + hdrlen;
+
+ if (unlikely(skb->len - hdrlen < 8)) {
+ if (net_ratelimit()) {
+ printk(KERN_DEBUG "%s: RX too short data frame "
+ "payload\n", dev->name);
+ }
+ return TXRX_DROP;
+ }
+
+ ethertype = (payload[6] << 8) | payload[7];
+
+ if (likely((memcmp(payload, rfc1042_header, 6) == 0 &&
+ ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
+ memcmp(payload, bridge_tunnel_header, 6) == 0)) {
+ /* remove RFC1042 or Bridge-Tunnel encapsulation and
+ * replace EtherType */
+ skb_pull(skb, hdrlen + 6);
+ } else {
+ skb_pull(skb, hdrlen);
+ }
+
+ eth = (struct ethhdr*)skb->data;
+
+ while ((u8*)eth < skb->data + skb->len) {
+ unsigned int eth_len = sizeof(struct ethhdr) +
+ ntohs(eth->h_proto);
+
+ frame = dev_alloc_skb(3000);
+
+ if (frame == NULL)
+ return TXRX_DROP;
+
+ frame->mac.raw = frame->data;
+ memcpy(skb_put(frame, eth_len), (u8*)eth, eth_len);
+
+ frame->dev = dev;
+
+ skb2 = NULL;
+
+ sdata->stats.rx_packets++;
+ sdata->stats.rx_bytes += frame->len;
+
+ if (local->bridge_packets &&
+ (sdata->type == IEEE80211_IF_TYPE_AP ||
+ sdata->type == IEEE80211_IF_TYPE_VLAN) &&
+ rx->u.rx.ra_match) {
+ if (is_multicast_ether_addr(frame->data)) {
+ /* send multicast frames both to higher layers
+ * in local net stack and back to the wireless
+ * media */
+ skb2 = skb_copy(frame, GFP_ATOMIC);
+ if (!skb2)
+ printk(KERN_DEBUG "%s: failed to clone "
+ "multicast frame\n", dev->name);
+ } else {
+ struct sta_info *dsta;
+ dsta = sta_info_get(local, frame->data);
+ if (dsta && !dsta->dev) {
+ printk(KERN_DEBUG "Station with null "
+ "dev structure!\n");
+ } else if (dsta && dsta->dev == dev) {
+ /* Destination station is associated
+ * to this AP, so send the frame
+ * directly to it and do not pass
+ * the frame to local net stack.
+ */
+ skb2 = skb;
+ skb = NULL;
+ }
+ if (dsta)
+ sta_info_put(dsta);
+ }
+ }
+ if (frame) {
+ /* deliver to local stack */
+ frame->protocol = eth_type_trans(frame, dev);
+ memset(frame->cb, 0, sizeof(frame->cb));
+ netif_rx(frame);
+ }
+
+ if (skb2) {
+ /* send to wireless media */
+ skb2->protocol = __constant_htons(ETH_P_802_3);
+ skb2->mac.raw = skb2->nh.raw = skb2->data;
+ dev_queue_xmit(skb2);
+ }
+
+ eth = (struct ethhdr*)((u8*)eth + eth_len
+ + calc_pad_len(eth_len));
+ }
+
+ dev_kfree_skb(skb);
+ return TXRX_QUEUED;
+}
+
static ieee80211_txrx_result
ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
{
@@ -4373,6 +4510,7 @@ static ieee80211_rx_handler ieee80211_rx
ieee80211_rx_h_remove_qos_control,
ieee80211_rx_h_802_1x_pae,
ieee80211_rx_h_drop_unencrypted,
+ ieee80211_rx_h_data_agg,
ieee80211_rx_h_data,
ieee80211_rx_h_mgmt,
NULL
diff -Nupr wireless-dev/net/mac80211/wme.h
wireless-dev-new/net/mac80211/wme.h
--- wireless-dev/net/mac80211/wme.h 2007-03-22 11:40:17.000000000 -0700
+++ wireless-dev-new/net/mac80211/wme.h 2007-03-27 01:48:34.000000000
-0700
@@ -24,6 +24,8 @@
#define QOS_CONTROL_TAG1D_MASK 0x07
+#define QOS_CONTROL_A_MSDU_PRESENT 0x80
+
ieee80211_txrx_result
ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx);
-
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