From 23a5708d4e78a97a8ee0b3bcbf93c81b43504b84 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Fri, 11 Jun 2021 14:05:29 -0500 Subject: [PATCH] net: qualcomm: rmnet: avoid unnecessary IPv6 byte-swapping In the previous patch IPv4 download checksum offload code was updated to avoid unnecessary byte swapping, based on properties of the Internet checksum algorithm. This patch makes comparable changes to the IPv6 download checksum offload handling. Signed-off-by: Alex Elder Signed-off-by: David S. Miller --- drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c index 39f198d..d4d23ab 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c @@ -123,10 +123,11 @@ rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, struct ipv6hdr *ip6h = (struct ipv6hdr *)skb->data; void *txporthdr = skb->data + sizeof(*ip6h); __sum16 *csum_field, pseudo_csum, csum_temp; - u16 csum_value, csum_value_final; __be16 ip6_hdr_csum, addend; __sum16 ip6_payload_csum; __be16 ip_header_csum; + u16 csum_value_final; + __be16 csum_value; u32 length; /* Checksum offload is only supported for UDP and TCP protocols; @@ -144,21 +145,21 @@ rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, * of the IP header from the trailer checksum. We then add the * checksum computed over the pseudo header. */ - csum_value = ~ntohs(csum_trailer->csum_value); + csum_value = ~csum_trailer->csum_value; ip_header_csum = (__force __be16)ip_fast_csum(ip6h, sizeof(*ip6h) / 4); - ip6_hdr_csum = (__force __be16)~ntohs(ip_header_csum); + ip6_hdr_csum = (__force __be16)~ip_header_csum; ip6_payload_csum = csum16_sub((__force __sum16)csum_value, ip6_hdr_csum); length = (ip6h->nexthdr == IPPROTO_UDP) ? ntohs(((struct udphdr *)txporthdr)->len) : ntohs(ip6h->payload_len); - pseudo_csum = ~(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, - length, ip6h->nexthdr, 0)); - addend = (__force __be16)ntohs((__force __be16)pseudo_csum); + pseudo_csum = ~csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, + length, ip6h->nexthdr, 0); + addend = (__force __be16)pseudo_csum; pseudo_csum = csum16_add(ip6_payload_csum, addend); - addend = (__force __be16)ntohs((__force __be16)*csum_field); + addend = (__force __be16)*csum_field; csum_temp = ~csum16_sub(pseudo_csum, addend); csum_value_final = (__force u16)csum_temp; @@ -179,7 +180,7 @@ rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, } } - if (csum_value_final == ntohs((__force __be16)*csum_field)) { + if (csum_value_final == (__force u16)*csum_field) { priv->stats.csum_ok++; return 0; } else { -- 2.7.4