mac80211: use reset to set header pointer

Since offset is zero, it's not necessary to use set function. Reset
function is straightforward, and will remove the unnecessary add
operation in set function.
Signed-off-by: NZhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/mac80211/mesh_hwmp.c

@@ -205,9 +205,9 @@ static void prepare_frame_for_deferred_tx(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 
-	skb_set_mac_header(skb, 0);
-	skb_set_network_header(skb, 0);
-	skb_set_transport_header(skb, 0);
+	skb_reset_mac_header(skb);
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
 
 	/* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
 	skb_set_queue_mapping(skb, IEEE80211_AC_VO);

net/mac80211/rx.c

@@ -3101,7 +3101,7 @@ static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
 					 false);
 
-	skb_set_mac_header(skb, 0);
+	skb_reset_mac_header(skb);
 	skb->ip_summed = CHECKSUM_UNNECESSARY;
 	skb->pkt_type = PACKET_OTHERHOST;
 	skb->protocol = htons(ETH_P_802_2);

net/mac80211/status.c

@@ -697,7 +697,7 @@ void ieee80211_tx_monitor(struct ieee80211_local *local, struct sk_buff *skb,
 					 rtap_len, shift);
 
 	/* XXX: is this sufficient for BPF? */
-	skb_set_mac_header(skb, 0);
+	skb_reset_mac_header(skb);
 	skb->ip_summed = CHECKSUM_UNNECESSARY;
 	skb->pkt_type = PACKET_OTHERHOST;
 	skb->protocol = htons(ETH_P_802_2);

net/mac80211/tx.c

@@ -2458,7 +2458,7 @@ static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
 	/* Update skb pointers to various headers since this modified frame
 	 * is going to go through Linux networking code that may potentially
 	 * need things like pointer to IP header. */
-	skb_set_mac_header(skb, 0);
+	skb_reset_mac_header(skb);
 	skb_set_network_header(skb, nh_pos);
 	skb_set_transport_header(skb, h_pos);
 
@@ -3973,9 +3973,9 @@ void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
 {
 	int ac = ieee802_1d_to_ac[tid & 7];
 
-	skb_set_mac_header(skb, 0);
-	skb_set_network_header(skb, 0);
-	skb_set_transport_header(skb, 0);
+	skb_reset_mac_header(skb);
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
 
 	skb_set_queue_mapping(skb, ac);
 	skb->priority = tid;