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3d5b459ba0
Note that like TCP, we do not support additional encapsulations, and that checksums must be offloaded to the NIC. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
98 lines
2.6 KiB
C
98 lines
2.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/export.h>
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#include <linux/if_vlan.h>
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#include <net/ip.h>
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#include <net/tso.h>
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#include <asm/unaligned.h>
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/* Calculate expected number of TX descriptors */
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int tso_count_descs(const struct sk_buff *skb)
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{
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/* The Marvell Way */
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return skb_shinfo(skb)->gso_segs * 2 + skb_shinfo(skb)->nr_frags;
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}
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EXPORT_SYMBOL(tso_count_descs);
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void tso_build_hdr(const struct sk_buff *skb, char *hdr, struct tso_t *tso,
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int size, bool is_last)
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{
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int hdr_len = skb_transport_offset(skb) + tso->tlen;
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int mac_hdr_len = skb_network_offset(skb);
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memcpy(hdr, skb->data, hdr_len);
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if (!tso->ipv6) {
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struct iphdr *iph = (void *)(hdr + mac_hdr_len);
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iph->id = htons(tso->ip_id);
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iph->tot_len = htons(size + hdr_len - mac_hdr_len);
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tso->ip_id++;
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} else {
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struct ipv6hdr *iph = (void *)(hdr + mac_hdr_len);
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iph->payload_len = htons(size + tso->tlen);
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}
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hdr += skb_transport_offset(skb);
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if (tso->tlen != sizeof(struct udphdr)) {
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struct tcphdr *tcph = (struct tcphdr *)hdr;
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put_unaligned_be32(tso->tcp_seq, &tcph->seq);
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if (!is_last) {
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/* Clear all special flags for not last packet */
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tcph->psh = 0;
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tcph->fin = 0;
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tcph->rst = 0;
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}
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} else {
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struct udphdr *uh = (struct udphdr *)hdr;
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uh->len = htons(sizeof(*uh) + size);
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}
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}
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EXPORT_SYMBOL(tso_build_hdr);
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void tso_build_data(const struct sk_buff *skb, struct tso_t *tso, int size)
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{
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tso->tcp_seq += size; /* not worth avoiding this operation for UDP */
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tso->size -= size;
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tso->data += size;
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if ((tso->size == 0) &&
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(tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
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skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
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/* Move to next segment */
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tso->size = skb_frag_size(frag);
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tso->data = skb_frag_address(frag);
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tso->next_frag_idx++;
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}
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}
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EXPORT_SYMBOL(tso_build_data);
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int tso_start(struct sk_buff *skb, struct tso_t *tso)
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{
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int tlen = skb_is_gso_tcp(skb) ? tcp_hdrlen(skb) : sizeof(struct udphdr);
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int hdr_len = skb_transport_offset(skb) + tlen;
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tso->tlen = tlen;
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tso->ip_id = ntohs(ip_hdr(skb)->id);
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tso->tcp_seq = (tlen != sizeof(struct udphdr)) ? ntohl(tcp_hdr(skb)->seq) : 0;
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tso->next_frag_idx = 0;
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tso->ipv6 = vlan_get_protocol(skb) == htons(ETH_P_IPV6);
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/* Build first data */
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tso->size = skb_headlen(skb) - hdr_len;
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tso->data = skb->data + hdr_len;
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if ((tso->size == 0) &&
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(tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
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skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
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/* Move to next segment */
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tso->size = skb_frag_size(frag);
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tso->data = skb_frag_address(frag);
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tso->next_frag_idx++;
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}
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return hdr_len;
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}
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EXPORT_SYMBOL(tso_start);
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