From 06f2bb1e017166c6413debc28cf72087679242fb Mon Sep 17 00:00:00 2001 From: Michael Braun Date: Sat, 15 Oct 2016 13:28:18 +0200 Subject: mac80211: avoid extra memcpy in A-MSDU head creation Signed-off-by: Michael Braun Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) (limited to 'net/mac80211') diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index f5d45e4bdccc..9661f5441686 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -3059,11 +3059,11 @@ static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata, struct ieee80211_local *local = sdata->local; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct ieee80211_hdr *hdr; - struct ethhdr amsdu_hdr; + struct ethhdr *amsdu_hdr; int hdr_len = fast_tx->hdr_len - sizeof(rfc1042_header); int subframe_len = skb->len - hdr_len; void *data; - u8 *qc; + u8 *qc, *h_80211_src, *h_80211_dst; if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) return false; @@ -3071,19 +3071,22 @@ static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata, if (info->control.flags & IEEE80211_TX_CTRL_AMSDU) return true; - if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(amsdu_hdr), + if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(*amsdu_hdr), &subframe_len)) return false; - amsdu_hdr.h_proto = cpu_to_be16(subframe_len); - memcpy(amsdu_hdr.h_source, skb->data + fast_tx->sa_offs, ETH_ALEN); - memcpy(amsdu_hdr.h_dest, skb->data + fast_tx->da_offs, ETH_ALEN); + data = skb_push(skb, sizeof(*amsdu_hdr)); + memmove(data, data + sizeof(*amsdu_hdr), hdr_len); + hdr = data; + amsdu_hdr = data + hdr_len; + /* h_80211_src/dst is addr* field within hdr */ + h_80211_src = data + fast_tx->sa_offs; + h_80211_dst = data + fast_tx->da_offs; - data = skb_push(skb, sizeof(amsdu_hdr)); - memmove(data, data + sizeof(amsdu_hdr), hdr_len); - memcpy(data + hdr_len, &amsdu_hdr, sizeof(amsdu_hdr)); + amsdu_hdr->h_proto = cpu_to_be16(subframe_len); + ether_addr_copy(amsdu_hdr->h_source, h_80211_src); + ether_addr_copy(amsdu_hdr->h_dest, h_80211_dst); - hdr = data; qc = ieee80211_get_qos_ctl(hdr); *qc |= IEEE80211_QOS_CTL_A_MSDU_PRESENT; -- cgit