mm: Use static initialization for "srcu"
[linux/fpc-iii.git] / net / core / tso.c
blob5dca7ce8ee9f58619ba1ac6c0bc85c73f208fe9d
1 #include <linux/export.h>
2 #include <linux/if_vlan.h>
3 #include <net/ip.h>
4 #include <net/tso.h>
5 #include <asm/unaligned.h>
7 /* Calculate expected number of TX descriptors */
8 int tso_count_descs(struct sk_buff *skb)
10 /* The Marvell Way */
11 return skb_shinfo(skb)->gso_segs * 2 + skb_shinfo(skb)->nr_frags;
13 EXPORT_SYMBOL(tso_count_descs);
15 void tso_build_hdr(struct sk_buff *skb, char *hdr, struct tso_t *tso,
16 int size, bool is_last)
18 struct tcphdr *tcph;
19 int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
20 int mac_hdr_len = skb_network_offset(skb);
22 memcpy(hdr, skb->data, hdr_len);
23 if (!tso->ipv6) {
24 struct iphdr *iph = (void *)(hdr + mac_hdr_len);
26 iph->id = htons(tso->ip_id);
27 iph->tot_len = htons(size + hdr_len - mac_hdr_len);
28 tso->ip_id++;
29 } else {
30 struct ipv6hdr *iph = (void *)(hdr + mac_hdr_len);
32 iph->payload_len = htons(size + tcp_hdrlen(skb));
34 tcph = (struct tcphdr *)(hdr + skb_transport_offset(skb));
35 put_unaligned_be32(tso->tcp_seq, &tcph->seq);
37 if (!is_last) {
38 /* Clear all special flags for not last packet */
39 tcph->psh = 0;
40 tcph->fin = 0;
41 tcph->rst = 0;
44 EXPORT_SYMBOL(tso_build_hdr);
46 void tso_build_data(struct sk_buff *skb, struct tso_t *tso, int size)
48 tso->tcp_seq += size;
49 tso->size -= size;
50 tso->data += size;
52 if ((tso->size == 0) &&
53 (tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
54 skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
56 /* Move to next segment */
57 tso->size = frag->size;
58 tso->data = page_address(frag->page.p) + frag->page_offset;
59 tso->next_frag_idx++;
62 EXPORT_SYMBOL(tso_build_data);
64 void tso_start(struct sk_buff *skb, struct tso_t *tso)
66 int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
68 tso->ip_id = ntohs(ip_hdr(skb)->id);
69 tso->tcp_seq = ntohl(tcp_hdr(skb)->seq);
70 tso->next_frag_idx = 0;
71 tso->ipv6 = vlan_get_protocol(skb) == htons(ETH_P_IPV6);
73 /* Build first data */
74 tso->size = skb_headlen(skb) - hdr_len;
75 tso->data = skb->data + hdr_len;
76 if ((tso->size == 0) &&
77 (tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
78 skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
80 /* Move to next segment */
81 tso->size = frag->size;
82 tso->data = page_address(frag->page.p) + frag->page_offset;
83 tso->next_frag_idx++;
86 EXPORT_SYMBOL(tso_start);