1 /*
2  * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2
6  * as published by the Free Software Foundation
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 #include "mt7601u.h"
15 
16 void mt76_remove_hdr_pad(struct sk_buff *skb)
17 {
18 	int len = ieee80211_get_hdrlen_from_skb(skb);
19 
20 	memmove(skb->data + 2, skb->data, len);
21 	skb_pull(skb, 2);
22 }
23 
24 int mt76_insert_hdr_pad(struct sk_buff *skb)
25 {
26 	int len = ieee80211_get_hdrlen_from_skb(skb);
27 	int ret;
28 
29 	if (len % 4 == 0)
30 		return 0;
31 
32 	ret = skb_cow(skb, 2);
33 	if (ret)
34 		return ret;
35 
36 	skb_push(skb, 2);
37 	memmove(skb->data, skb->data + 2, len);
38 
39 	skb->data[len] = 0;
40 	skb->data[len + 1] = 0;
41 	return 0;
42 }
43