[NET]: Merge TSO/UFO fields in sk_buff
Having separate fields in sk_buff for TSO/UFO (tso_size/ufo_size) is not
going to scale if we add any more segmentation methods (e.g., DCCP). So
let's merge them.
They were used to tell the protocol of a packet. This function has been
subsumed by the new gso_type field. This is essentially a set of netdev
feature bits (shifted by 16 bits) that are required to process a specific
skb. As such it's easy to tell whether a given device can process a GSO
skb: you just have to and the gso_type field and the netdev's features
field.
I've made gso_type a conjunction. The idea is that you have a base type
(e.g., SKB_GSO_TCPV4) that can be modified further to support new features.
For example, if we add a hardware TSO type that supports ECN, they would
declare NETIF_F_TSO | NETIF_F_TSO_ECN. All TSO packets with CWR set would
have a gso_type of SKB_GSO_TCPV4 | SKB_GSO_TCPV4_ECN while all other TSO
packets would be SKB_GSO_TCPV4. This means that only the CWR packets need
to be emulated in software.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 07bb5a2..bdd71db 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -515,15 +515,17 @@
/* Avoid the costly divide in the normal
* non-TSO case.
*/
- skb_shinfo(skb)->tso_segs = 1;
- skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
} else {
unsigned int factor;
factor = skb->len + (mss_now - 1);
factor /= mss_now;
- skb_shinfo(skb)->tso_segs = factor;
- skb_shinfo(skb)->tso_size = mss_now;
+ skb_shinfo(skb)->gso_segs = factor;
+ skb_shinfo(skb)->gso_size = mss_now;
+ skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
}
}
@@ -914,7 +916,7 @@
if (!tso_segs ||
(tso_segs > 1 &&
- skb_shinfo(skb)->tso_size != mss_now)) {
+ tcp_skb_mss(skb) != mss_now)) {
tcp_set_skb_tso_segs(sk, skb, mss_now);
tso_segs = tcp_skb_pcount(skb);
}
@@ -1724,8 +1726,9 @@
tp->snd_una == (TCP_SKB_CB(skb)->end_seq - 1)) {
if (!pskb_trim(skb, 0)) {
TCP_SKB_CB(skb)->seq = TCP_SKB_CB(skb)->end_seq - 1;
- skb_shinfo(skb)->tso_segs = 1;
- skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
skb->ip_summed = CHECKSUM_NONE;
skb->csum = 0;
}
@@ -1930,8 +1933,9 @@
skb->csum = 0;
TCP_SKB_CB(skb)->flags = (TCPCB_FLAG_ACK | TCPCB_FLAG_FIN);
TCP_SKB_CB(skb)->sacked = 0;
- skb_shinfo(skb)->tso_segs = 1;
- skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
/* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */
TCP_SKB_CB(skb)->seq = tp->write_seq;
@@ -1963,8 +1967,9 @@
skb->csum = 0;
TCP_SKB_CB(skb)->flags = (TCPCB_FLAG_ACK | TCPCB_FLAG_RST);
TCP_SKB_CB(skb)->sacked = 0;
- skb_shinfo(skb)->tso_segs = 1;
- skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
/* Send it off. */
TCP_SKB_CB(skb)->seq = tcp_acceptable_seq(sk, tp);
@@ -2047,8 +2052,9 @@
TCP_SKB_CB(skb)->seq = tcp_rsk(req)->snt_isn;
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq + 1;
TCP_SKB_CB(skb)->sacked = 0;
- skb_shinfo(skb)->tso_segs = 1;
- skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
th->seq = htonl(TCP_SKB_CB(skb)->seq);
th->ack_seq = htonl(tcp_rsk(req)->rcv_isn + 1);
if (req->rcv_wnd == 0) { /* ignored for retransmitted syns */
@@ -2152,8 +2158,9 @@
TCP_SKB_CB(buff)->flags = TCPCB_FLAG_SYN;
TCP_ECN_send_syn(sk, tp, buff);
TCP_SKB_CB(buff)->sacked = 0;
- skb_shinfo(buff)->tso_segs = 1;
- skb_shinfo(buff)->tso_size = 0;
+ skb_shinfo(buff)->gso_segs = 1;
+ skb_shinfo(buff)->gso_size = 0;
+ skb_shinfo(buff)->gso_type = 0;
buff->csum = 0;
TCP_SKB_CB(buff)->seq = tp->write_seq++;
TCP_SKB_CB(buff)->end_seq = tp->write_seq;
@@ -2257,8 +2264,9 @@
buff->csum = 0;
TCP_SKB_CB(buff)->flags = TCPCB_FLAG_ACK;
TCP_SKB_CB(buff)->sacked = 0;
- skb_shinfo(buff)->tso_segs = 1;
- skb_shinfo(buff)->tso_size = 0;
+ skb_shinfo(buff)->gso_segs = 1;
+ skb_shinfo(buff)->gso_size = 0;
+ skb_shinfo(buff)->gso_type = 0;
/* Send it off, this clears delayed acks for us. */
TCP_SKB_CB(buff)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk, tp);
@@ -2293,8 +2301,9 @@
skb->csum = 0;
TCP_SKB_CB(skb)->flags = TCPCB_FLAG_ACK;
TCP_SKB_CB(skb)->sacked = urgent;
- skb_shinfo(skb)->tso_segs = 1;
- skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
/* Use a previous sequence. This should cause the other
* end to send an ack. Don't queue or clone SKB, just