static void lro_add_common(struct net_lro_desc *lro_desc, struct iphdr *iph,
struct tcphdr *tcph, int tcp_data_len)
{
struct sk_buff *parent = lro_desc->parent;
__be32 *topt;
lro_desc->pkt_aggr_cnt++;
lro_desc->ip_tot_len += tcp_data_len;
lro_desc->tcp_next_seq += tcp_data_len;
lro_desc->tcp_window = tcph->window;
lro_desc->tcp_ack = tcph->ack_seq;
/* don't update tcp_rcv_tsval, would not work with PAWS */
if (lro_desc->tcp_saw_tstamp) {
topt = (__be32 *) (tcph + 1);
lro_desc->tcp_rcv_tsecr = *(topt + 2);
}
lro_desc->data_csum = csum_block_add(lro_desc->data_csum,
lro_tcp_data_csum(iph, tcph,
tcp_data_len),
parent->len);
parent->len += tcp_data_len;
parent->data_len += tcp_data_len;
if (tcp_data_len > lro_desc->mss)
lro_desc->mss = tcp_data_len;
}
/**
* xdr_skb_read_and_csum_bits - copy and checksum from skb to buffer
* @desc: sk_buff copy helper
* @to: copy destination
* @len: number of bytes to copy
*
* Same as skb_read_bits, but calculate a checksum at the same time.
*/
static size_t xdr_skb_read_and_csum_bits(struct xdr_skb_reader *desc, void *to, size_t len)
{
unsigned int pos;
__wsum csum2;
if (len > desc->count)
len = desc->count;
pos = desc->offset;
csum2 = skb_copy_and_csum_bits(desc->skb, pos, to, len, 0);
desc->csum = csum_block_add(desc->csum, csum2, pos);
desc->count -= len;
desc->offset += len;
return len;
}
static inline void skb_copy_and_csum_datagram_kvec_dst(const struct sk_buff *skb, int offset, struct kvec_dst *dst, int len, unsigned int *csump)
{
int i, copy;
int start = skb->len - skb->data_len;
int pos = 0;
/* Copy header. */
if ((copy = start-offset) > 0) {
if (copy > len)
copy = len;
*csump = csum_and_copy_to_dst(dst, skb->data+offset, copy, *csump);
if ((len -= copy) == 0)
return;
offset += copy;
pos = copy;
}
for (i=0; i<skb_shinfo(skb)->nr_frags; i++) {
int end;
BUG_TRAP(start <= offset+len);
end = start + skb_shinfo(skb)->frags[i].size;
if ((copy = end-offset) > 0) {
unsigned int csum2;
u8 *vaddr;
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
struct page *page = frag->page;
if (copy > len)
copy = len;
vaddr = kmap_atomic(page, KM_USER1);
csum2 = csum_and_copy_to_dst(dst,
vaddr + frag->page_offset + offset-start,
copy, 0);
kunmap_atomic(vaddr, KM_USER1);
*csump = csum_block_add(*csump, csum2, pos);
if (!(len -= copy))
return;
offset += copy;
pos += copy;
}
start = end;
}
if (skb_shinfo(skb)->frag_list) {
struct sk_buff *list;
for (list = skb_shinfo(skb)->frag_list; list; list=list->next) {
int end;
BUG_TRAP(start <= offset+len);
end = start + list->len;
if ((copy = end-offset) > 0) {
unsigned int csum2 = 0;
if (copy > len)
copy = len;
skb_copy_and_csum_datagram_kvec_dst(list, offset-start, dst, copy, &csum2);
*csump = csum_block_add(*csump, csum2, pos);
if ((len -= copy) == 0)
return;
offset += copy;
pos += copy;
}
start = end;
}
}
}
int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, u8 *to, int len, unsigned int *csump)
{
int i, copy;
int start = skb->len - skb->data_len;
int pos = 0;
/* Copy header. */
if ((copy = start-offset) > 0) {
int err = 0;
if (copy > len)
copy = len;
*csump = csum_and_copy_to_user(skb->data+offset, to, copy, *csump, &err);
if (err)
goto fault;
if ((len -= copy) == 0)
return 0;
offset += copy;
to += copy;
pos = copy;
}
for (i=0; i<skb_shinfo(skb)->nr_frags; i++) {
int end;
BUG_TRAP(start <= offset+len);
end = start + skb_shinfo(skb)->frags[i].size;
if ((copy = end-offset) > 0) {
unsigned int csum2;
int err = 0;
u8 *vaddr;
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
struct page *page = frag->page;
if (copy > len)
copy = len;
vaddr = kmap(page);
csum2 = csum_and_copy_to_user(vaddr + frag->page_offset +
offset-start, to, copy, 0, &err);
kunmap(page);
if (err)
goto fault;
*csump = csum_block_add(*csump, csum2, pos);
if (!(len -= copy))
return 0;
offset += copy;
to += copy;
pos += copy;
}
start = end;
}
if (skb_shinfo(skb)->frag_list) {
struct sk_buff *list;
for (list = skb_shinfo(skb)->frag_list; list; list=list->next) {
int end;
BUG_TRAP(start <= offset+len);
end = start + list->len;
if ((copy = end-offset) > 0) {
unsigned int csum2 = 0;
if (copy > len)
copy = len;
if (skb_copy_and_csum_datagram(list, offset-start, to, copy, &csum2))
goto fault;
*csump = csum_block_add(*csump, csum2, pos);
if ((len -= copy) == 0)
return 0;
offset += copy;
to += copy;
pos += copy;
}
start = end;
}
}
if (len == 0)
return 0;
fault:
return -EFAULT;
}
