mac80211: trim RX data

The RX data contains the netdev, which is
duplicated since we have the sdata, and the
RX status pointer, which is duplicate since
we have the skb. Remove those two fields to
have fewer fields that depend on each other
and simply load them as necessary.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 37e9891..904aaea 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -477,7 +477,7 @@
 {
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 	unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
-	char *dev_addr = rx->dev->dev_addr;
+	char *dev_addr = rx->sdata->dev->dev_addr;
 
 	if (ieee80211_is_data(hdr->frame_control)) {
 		if (is_multicast_ether_addr(hdr->addr1)) {
@@ -591,7 +591,9 @@
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 {
-	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
+	struct sk_buff *skb = rx->skb;
+	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 	int keyidx;
 	int hdrlen;
 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
@@ -645,8 +647,8 @@
 			return RX_CONTINUE;
 	} else if (mmie_keyidx >= 0) {
 		/* Broadcast/multicast robust management frame / BIP */
-		if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
-		    (rx->status->flag & RX_FLAG_IV_STRIPPED))
+		if ((status->flag & RX_FLAG_DECRYPTED) &&
+		    (status->flag & RX_FLAG_IV_STRIPPED))
 			return RX_CONTINUE;
 
 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
@@ -678,8 +680,8 @@
 		 * we somehow allow the driver to tell us which key
 		 * the hardware used if this flag is set?
 		 */
-		if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
-		    (rx->status->flag & RX_FLAG_IV_STRIPPED))
+		if ((status->flag & RX_FLAG_DECRYPTED) &&
+		    (status->flag & RX_FLAG_IV_STRIPPED))
 			return RX_CONTINUE;
 
 		hdrlen = ieee80211_hdrlen(hdr->frame_control);
@@ -715,8 +717,8 @@
 	/* Check for weak IVs if possible */
 	if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 	    ieee80211_is_data(hdr->frame_control) &&
-	    (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
-	     !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
+	    (!(status->flag & RX_FLAG_IV_STRIPPED) ||
+	     !(status->flag & RX_FLAG_DECRYPTED)) &&
 	    ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 		rx->sta->wep_weak_iv_count++;
 
@@ -736,7 +738,7 @@
 	}
 
 	/* either the frame has been decrypted or will be dropped */
-	rx->status->flag |= RX_FLAG_DECRYPTED;
+	status->flag |= RX_FLAG_DECRYPTED;
 
 	return result;
 }
@@ -816,7 +818,9 @@
 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 {
 	struct sta_info *sta = rx->sta;
-	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
+	struct sk_buff *skb = rx->skb;
+	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 
 	if (!sta)
 		return RX_CONTINUE;
@@ -847,8 +851,8 @@
 
 	sta->rx_fragments++;
 	sta->rx_bytes += rx->skb->len;
-	sta->last_signal = rx->status->signal;
-	sta->last_noise = rx->status->noise;
+	sta->last_signal = status->signal;
+	sta->last_noise = status->noise;
 
 	/*
 	 * Change STA power saving mode only at the end of a frame
@@ -1140,11 +1144,14 @@
 static int
 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
 {
+	struct sk_buff *skb = rx->skb;
+	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+
 	/*
 	 * Pass through unencrypted frames if the hardware has
 	 * decrypted them already.
 	 */
-	if (rx->status->flag & RX_FLAG_DECRYPTED)
+	if (status->flag & RX_FLAG_DECRYPTED)
 		return 0;
 
 	/* Drop unencrypted frames if key is set. */
@@ -1178,8 +1185,8 @@
 static int
 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
 {
-	struct net_device *dev = rx->dev;
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	struct ieee80211_sub_if_data *sdata = rx->sdata;
+	struct net_device *dev = sdata->dev;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 
 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->use_4addr &&
@@ -1205,7 +1212,7 @@
 	 * of whether the frame was encrypted or not.
 	 */
 	if (ehdr->h_proto == htons(ETH_P_PAE) &&
-	    (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
+	    (compare_ether_addr(ehdr->h_dest, rx->sdata->dev->dev_addr) == 0 ||
 	     compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
 		return true;
 
@@ -1222,10 +1229,10 @@
 static void
 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
 {
-	struct net_device *dev = rx->dev;
+	struct ieee80211_sub_if_data *sdata = rx->sdata;
+	struct net_device *dev = sdata->dev;
 	struct ieee80211_local *local = rx->local;
 	struct sk_buff *skb, *xmit_skb;
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
 	struct sta_info *dsta;
 
@@ -1306,7 +1313,7 @@
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
 {
-	struct net_device *dev = rx->dev;
+	struct net_device *dev = rx->sdata->dev;
 	struct ieee80211_local *local = rx->local;
 	u16 ethertype;
 	u8 *payload;
@@ -1431,12 +1438,11 @@
 	unsigned int hdrlen;
 	struct sk_buff *skb = rx->skb, *fwd_skb;
 	struct ieee80211_local *local = rx->local;
-	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_sub_if_data *sdata = rx->sdata;
 
 	hdr = (struct ieee80211_hdr *) skb->data;
 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
-	sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 
 	if (!ieee80211_is_data(hdr->frame_control))
 		return RX_CONTINUE;
@@ -1474,7 +1480,7 @@
 
 	/* Frame has reached destination.  Don't forward */
 	if (!is_multicast_ether_addr(hdr->addr1) &&
-			compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
+	    compare_ether_addr(sdata->dev->dev_addr, hdr->addr3) == 0)
 		return RX_CONTINUE;
 
 	mesh_hdr->ttl--;
@@ -1491,10 +1497,10 @@
 
 			if (!fwd_skb && net_ratelimit())
 				printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
-						   rx->dev->name);
+						   sdata->dev->name);
 
 			fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
-			memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
+			memcpy(fwd_hdr->addr2, sdata->dev->dev_addr, ETH_ALEN);
 			info = IEEE80211_SKB_CB(fwd_skb);
 			memset(info, 0, sizeof(*info));
 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
@@ -1528,7 +1534,7 @@
 	}
 
 	if (is_multicast_ether_addr(hdr->addr1) ||
-	    rx->dev->flags & IFF_PROMISC)
+	    sdata->dev->flags & IFF_PROMISC)
 		return RX_CONTINUE;
 	else
 		return RX_DROP_MONITOR;
@@ -1538,9 +1544,9 @@
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
 {
-	struct net_device *dev = rx->dev;
+	struct ieee80211_sub_if_data *sdata = rx->sdata;
+	struct net_device *dev = sdata->dev;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	__le16 fc = hdr->frame_control;
 	int err;
 
@@ -1664,7 +1670,7 @@
 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
 {
 	struct ieee80211_local *local = rx->local;
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
+	struct ieee80211_sub_if_data *sdata = rx->sdata;
 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
 	int len = rx->skb->len;
 
@@ -1776,7 +1782,7 @@
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
 {
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
+	struct ieee80211_sub_if_data *sdata = rx->sdata;
 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
 
 	if (!(rx->flags & IEEE80211_RX_RA_MATCH))
@@ -1852,7 +1858,7 @@
 	} __attribute__ ((packed)) *rthdr;
 	struct sk_buff *skb = rx->skb, *skb2;
 	struct net_device *prev_dev = NULL;
-	struct ieee80211_rx_status *status = rx->status;
+	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 
 	if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
 		goto out_free_skb;
@@ -1928,7 +1934,6 @@
 
 	rx->skb = skb;
 	rx->sdata = sdata;
-	rx->dev = sdata->dev;
 
 #define CALL_RXH(rxh)			\
 	do {				\
@@ -1987,7 +1992,9 @@
 				struct ieee80211_rx_data *rx,
 				struct ieee80211_hdr *hdr)
 {
-	u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
+	struct sk_buff *skb = rx->skb;
+	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
 	int multicast = is_multicast_ether_addr(hdr->addr1);
 
 	switch (sdata->vif.type) {
@@ -2019,10 +2026,10 @@
 			rx->flags &= ~IEEE80211_RX_RA_MATCH;
 		} else if (!rx->sta) {
 			int rate_idx;
-			if (rx->status->flag & RX_FLAG_HT)
+			if (status->flag & RX_FLAG_HT)
 				rate_idx = 0; /* TODO: HT rates */
 			else
-				rate_idx = rx->status->rate_idx;
+				rate_idx = status->rate_idx;
 			rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
 				BIT(rate_idx));
 		}
@@ -2088,7 +2095,6 @@
 	memset(&rx, 0, sizeof(rx));
 	rx.skb = skb;
 	rx.local = local;
-	rx.status = status;
 	rx.rate = rate;
 
 	if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
@@ -2102,10 +2108,8 @@
 	ieee80211_verify_alignment(&rx);
 
 	rx.sta = sta_info_get(local, hdr->addr2);
-	if (rx.sta) {
+	if (rx.sta)
 		rx.sdata = rx.sta->sdata;
-		rx.dev = rx.sta->sdata->dev;
-	}
 
 	if (rx.sdata && ieee80211_is_data(hdr->frame_control)) {
 		rx.flags |= IEEE80211_RX_RA_MATCH;