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net: qualcomm: rmnet: remove some local variables
authorAlex Elder <elder@linaro.org>
Sat, 12 Jun 2021 14:37:29 +0000 (09:37 -0500)
committerDavid S. Miller <davem@davemloft.net>
Sat, 12 Jun 2021 20:18:48 +0000 (13:18 -0700)
In rmnet_map_ipv4_dl_csum_trailer(), remove the "csum_temp" and
"addend" local variables, and simplify a few lines of code.

Remove the "csum_temp", "csum_value", "ip6_hdr_csum", and "addend"
local variables in rmnet_map_ipv6_dl_csum_trailer(), and simplify a
few lines of code there as well.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c

index d4d23ab..3e6feef 100644 (file)
@@ -35,10 +35,9 @@ rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb,
 {
        struct iphdr *ip4h = (struct iphdr *)skb->data;
        void *txporthdr = skb->data + ip4h->ihl * 4;
-       __sum16 *csum_field, csum_temp, pseudo_csum;
+       __sum16 *csum_field, pseudo_csum;
        __sum16 ip_payload_csum;
-       u16 csum_value_final;
-       __be16 addend;
+       __sum16 csum_value_final;
 
        /* Computing the checksum over just the IPv4 header--including its
         * checksum field--should yield 0.  If it doesn't, the IP header
@@ -83,14 +82,11 @@ rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb,
        pseudo_csum = ~csum_tcpudp_magic(ip4h->saddr, ip4h->daddr,
                                         ntohs(ip4h->tot_len) - ip4h->ihl * 4,
                                         ip4h->protocol, 0);
-       addend = (__force __be16)pseudo_csum;
-       pseudo_csum = csum16_add(ip_payload_csum, addend);
+       pseudo_csum = csum16_add(ip_payload_csum, (__force __be16)pseudo_csum);
 
-       addend = (__force __be16)*csum_field;
-       csum_temp = ~csum16_sub(pseudo_csum, addend);
-       csum_value_final = (__force u16)csum_temp;
+       csum_value_final = ~csum16_sub(pseudo_csum, (__force __be16)*csum_field);
 
-       if (unlikely(csum_value_final == 0)) {
+       if (unlikely(!csum_value_final)) {
                switch (ip4h->protocol) {
                case IPPROTO_UDP:
                        /* RFC 768 - DL4 1's complement rule for UDP csum 0 */
@@ -105,7 +101,7 @@ rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb,
                }
        }
 
-       if (csum_value_final == (__force u16)*csum_field) {
+       if (csum_value_final == *csum_field) {
                priv->stats.csum_ok++;
                return 0;
        } else {
@@ -122,12 +118,10 @@ 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;
-       __be16 ip6_hdr_csum, addend;
+       __sum16 *csum_field, pseudo_csum;
        __sum16 ip6_payload_csum;
        __be16 ip_header_csum;
-       u16 csum_value_final;
-       __be16 csum_value;
+       __sum16 csum_value_final;
        u32 length;
 
        /* Checksum offload is only supported for UDP and TCP protocols;
@@ -145,23 +139,18 @@ 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 = ~csum_trailer->csum_value;
        ip_header_csum = (__force __be16)ip_fast_csum(ip6h, sizeof(*ip6h) / 4);
-       ip6_hdr_csum = (__force __be16)~ip_header_csum;
-       ip6_payload_csum = csum16_sub((__force __sum16)csum_value,
-                                     ip6_hdr_csum);
+       ip6_payload_csum = csum16_sub((__force __sum16)~csum_trailer->csum_value,
+                                     ~ip_header_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)pseudo_csum;
-       pseudo_csum = csum16_add(ip6_payload_csum, addend);
+       pseudo_csum = csum16_add(ip6_payload_csum, (__force __be16)pseudo_csum);
 
-       addend = (__force __be16)*csum_field;
-       csum_temp = ~csum16_sub(pseudo_csum, addend);
-       csum_value_final = (__force u16)csum_temp;
+       csum_value_final = ~csum16_sub(pseudo_csum, (__force __be16)*csum_field);
 
        if (unlikely(csum_value_final == 0)) {
                switch (ip6h->nexthdr) {
@@ -180,7 +169,7 @@ rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
                }
        }
 
-       if (csum_value_final == (__force u16)*csum_field) {
+       if (csum_value_final == *csum_field) {
                priv->stats.csum_ok++;
                return 0;
        } else {