Hi Subash, Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on net-next/master] url: https://github.com/0day-ci/linux/commits/Subash-Abhinov-Kasiviswanathan/net-qualcomm-rmnet-Enable-csum-offloads/20171228-041216 reproduce: # apt-get install sparse make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__ sparse warnings: (new ones prefixed by >>) vim +187 drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c 106 107 #if IS_ENABLED(CONFIG_IPV6) 108 static int 109 rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, 110 struct rmnet_map_dl_csum_trailer *csum_trailer) 111 { 112 u16 ip_pseudo_payload_csum, pseudo_csum, ip6_hdr_csum, *csum_field; 113 u16 csum_value, ip6_payload_csum, csum_value_final; 114 struct ipv6hdr *ip6h; 115 void *txporthdr; 116 u32 length; 117 118 ip6h = (struct ipv6hdr *)(skb->data); 119 120 txporthdr = skb->data + sizeof(struct ipv6hdr); 121 csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr); 122 123 if (!csum_field) 124 return -EPROTONOSUPPORT; 125 126 csum_value = ~ntohs(csum_trailer->csum_value); 127 ip6_hdr_csum = ~ntohs(ip_compute_csum(ip6h, 128 (int)(txporthdr - (void *)(skb->data)))); 129 ip6_payload_csum = csum16_sub(csum_value, ip6_hdr_csum); 130 131 length = (ip6h->nexthdr == IPPROTO_UDP) ? 132 ntohs(((struct udphdr *)txporthdr)->len) : 133 ntohs(ip6h->payload_len); 134 pseudo_csum = ~ntohs(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, 135 length, ip6h->nexthdr, 0)); 136 ip_pseudo_payload_csum = csum16_add(ip6_payload_csum, pseudo_csum); 137 > 138 csum_value_final = ~csum16_sub(ip_pseudo_payload_csum, > 139 ntohs(*csum_field)); 140 141 if (unlikely(csum_value_final == 0)) { 142 switch (ip6h->nexthdr) { 143 case IPPROTO_UDP: 144 /* RFC 2460 section 8.1 145 * DL6 One's complement rule for UDP checksum 0 146 */ 147 csum_value_final = ~csum_value_final; 148 break; 149 150 case IPPROTO_TCP: 151 /* DL6 Non-RFC compliant TCP checksum found */ 152 if (*csum_field == 0xFFFF) 153 csum_value_final = ~csum_value_final; 154 break; 155 } 156 } 157 158 if (csum_value_final == ntohs(*csum_field)) 159 return 0; 160 else 161 return -EINVAL; 162 } 163 #endif 164 165 static void rmnet_map_complement_ipv4_txporthdr_csum_field(void *iphdr) 166 { 167 struct iphdr *ip4h = (struct iphdr *)iphdr; 168 void *txphdr; 169 u16 *csum; 170 171 txphdr = iphdr + ip4h->ihl * 4; 172 173 if (ip4h->protocol == IPPROTO_TCP || ip4h->protocol == IPPROTO_UDP) { 174 csum = (u16 *)rmnet_map_get_csum_field(ip4h->protocol, txphdr); 175 *csum = ~(*csum); 176 } 177 } 178 179 static void 180 rmnet_map_ipv4_ul_csum_header(void *iphdr, 181 struct rmnet_map_ul_csum_header *ul_header, 182 struct sk_buff *skb) 183 { 184 struct iphdr *ip4h = (struct iphdr *)iphdr; 185 u16 *hdr = (u16 *)ul_header; 186 > 187 ul_header->csum_start_offset = > htons((u16)(skb_transport_header(skb) - 188 (unsigned char *)iphdr)); 189 ul_header->csum_insert_offset = skb->csum_offset; 190 ul_header->csum_enabled = 1; 191 if (ip4h->protocol == IPPROTO_UDP) 192 ul_header->udp_ip4_ind = 1; 193 else 194 ul_header->udp_ip4_ind = 0; 195 196 /* Changing remaining fields to network order */ 197 hdr++; > 198 *hdr = htons(*hdr); 199 200 skb->ip_summed = CHECKSUM_NONE; 201 202 rmnet_map_complement_ipv4_txporthdr_csum_field(iphdr); 203 } 204 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
