mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-27 06:34:11 +08:00
a63ba13eec
The crafted header start address is from a driver supplied buffer, which one can reasonably expect to be aligned on a 4-bytes boundary. However ATM the TSO helper API is only used by ethernet drivers and the tcp header will then be aligned to a 2-bytes only boundary from the header start address. Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com> Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by: David S. Miller <davem@davemloft.net>
79 lines
2.1 KiB
C
79 lines
2.1 KiB
C
#include <linux/export.h>
|
|
#include <net/ip.h>
|
|
#include <net/tso.h>
|
|
#include <asm/unaligned.h>
|
|
|
|
/* Calculate expected number of TX descriptors */
|
|
int tso_count_descs(struct sk_buff *skb)
|
|
{
|
|
/* The Marvell Way */
|
|
return skb_shinfo(skb)->gso_segs * 2 + skb_shinfo(skb)->nr_frags;
|
|
}
|
|
EXPORT_SYMBOL(tso_count_descs);
|
|
|
|
void tso_build_hdr(struct sk_buff *skb, char *hdr, struct tso_t *tso,
|
|
int size, bool is_last)
|
|
{
|
|
struct iphdr *iph;
|
|
struct tcphdr *tcph;
|
|
int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
|
|
int mac_hdr_len = skb_network_offset(skb);
|
|
|
|
memcpy(hdr, skb->data, hdr_len);
|
|
iph = (struct iphdr *)(hdr + mac_hdr_len);
|
|
iph->id = htons(tso->ip_id);
|
|
iph->tot_len = htons(size + hdr_len - mac_hdr_len);
|
|
tcph = (struct tcphdr *)(hdr + skb_transport_offset(skb));
|
|
put_unaligned_be32(tso->tcp_seq, &tcph->seq);
|
|
tso->ip_id++;
|
|
|
|
if (!is_last) {
|
|
/* Clear all special flags for not last packet */
|
|
tcph->psh = 0;
|
|
tcph->fin = 0;
|
|
tcph->rst = 0;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(tso_build_hdr);
|
|
|
|
void tso_build_data(struct sk_buff *skb, struct tso_t *tso, int size)
|
|
{
|
|
tso->tcp_seq += size;
|
|
tso->size -= size;
|
|
tso->data += size;
|
|
|
|
if ((tso->size == 0) &&
|
|
(tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
|
|
skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
|
|
|
|
/* Move to next segment */
|
|
tso->size = frag->size;
|
|
tso->data = page_address(frag->page.p) + frag->page_offset;
|
|
tso->next_frag_idx++;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(tso_build_data);
|
|
|
|
void tso_start(struct sk_buff *skb, struct tso_t *tso)
|
|
{
|
|
int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
|
|
|
|
tso->ip_id = ntohs(ip_hdr(skb)->id);
|
|
tso->tcp_seq = ntohl(tcp_hdr(skb)->seq);
|
|
tso->next_frag_idx = 0;
|
|
|
|
/* Build first data */
|
|
tso->size = skb_headlen(skb) - hdr_len;
|
|
tso->data = skb->data + hdr_len;
|
|
if ((tso->size == 0) &&
|
|
(tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
|
|
skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
|
|
|
|
/* Move to next segment */
|
|
tso->size = frag->size;
|
|
tso->data = page_address(frag->page.p) + frag->page_offset;
|
|
tso->next_frag_idx++;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(tso_start);
|