From: Willem de Bruijn <will...@google.com>
Very rough initial version of udp gro, for discussion purpose only at
this point.
Among others it
- lacks the cmsg UDP_SEGMENT to return gso_size
- probably breaks udp tunnels
- hard breaks at 40 segments
- does not allow a last segment of unequal size
Signed-off-by: Willem de Bruijn <will...@google.com>
---
include/uapi/linux/udp.h | 1 +
net/ipv4/udp.c | 71 ++++++++++++++++++++++++++++++++++++++++
net/ipv4/udp_offload.c | 11 +++----
3 files changed, 76 insertions(+), 7 deletions(-)
diff --git a/include/uapi/linux/udp.h b/include/uapi/linux/udp.h
index 09d00f8c442b..7fda3e8c7fcf 100644
--- a/include/uapi/linux/udp.h
+++ b/include/uapi/linux/udp.h
@@ -33,6 +33,7 @@ struct udphdr {
#define UDP_NO_CHECK6_TX 101 /* Disable sending checksum for UDP6X */
#define UDP_NO_CHECK6_RX 102 /* Disable accpeting checksum for UDP6 */
#define UDP_SEGMENT 103 /* Set GSO segmentation size */
+#define UDP_GRO 104 /* Enable GRO */
/* UDP encapsulation types */
#define UDP_ENCAP_ESPINUDP_NON_IKE 1 /* draft-ietf-ipsec-nat-t-ike-00/01 */
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index bd873a5b8a86..ae49c08e6225 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -2387,6 +2387,51 @@ void udp_destroy_sock(struct sock *sk)
}
}
+static struct sk_buff *udp_gro_receive_cb(struct sock *sk,
+ struct list_head *head,
+ struct sk_buff *skb)
+{
+ struct sk_buff *p;
+ unsigned int off;
+
+ off = skb_gro_offset(skb) - sizeof(struct udphdr);
+
+ list_for_each_entry(p, head, list) {
+ if (!NAPI_GRO_CB(p)->same_flow)
+ continue;
+
+ /* TODO: for UDP_GRO: match size unless last segment */
+ if (NAPI_GRO_CB(p)->flush)
+ break;
+
+ /* TODO: look into ip id check */
+ if (skb_gro_receive(p, skb)) {
+ NAPI_GRO_CB(skb)->flush = 1;
+ break;
+ }
+
+ if (NAPI_GRO_CB(skb)->count >= 40) {
+ return p;
+ }
+
+ return NULL;
+ }
+
+ return NULL;
+}
+
+static int udp_gro_complete_cb(struct sock *sk, struct sk_buff *skb,
+ int nhoff)
+{
+ skb->csum_start = (unsigned char *)udp_hdr(skb) - skb->head;
+ skb->csum_offset = offsetof(struct udphdr, check);
+ skb->ip_summed = CHECKSUM_PARTIAL;
+
+ skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count;
+
+ return 0;
+}
+
/*
* Socket option code for UDP
*/
@@ -2450,6 +2495,32 @@ int udp_lib_setsockopt(struct sock *sk, int level, int
optname,
up->gso_size = val;
break;
+ case UDP_GRO:
+ {
+ if (val < 0 || val > 1)
+ return -EINVAL;
+
+ lock_sock(sk);
+ if (val) {
+
+ if (!udp_sk(sk)->gro_receive) {
+ udp_sk(sk)->gro_complete = udp_gro_complete_cb;
+ udp_sk(sk)->gro_receive = udp_gro_receive_cb;
+ } else {
+ err = -EALREADY;
+ }
+ } else {
+ if (udp_sk(sk)->gro_receive) {
+ udp_sk(sk)->gro_receive = NULL;
+ udp_sk(sk)->gro_complete = NULL;
+ } else {
+ err = -ENOENT;
+ }
+ }
+ release_sock(sk);
+ break;
+ }
+
/*
* UDP-Lite's partial checksum coverage (RFC 3828).
*/
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index f44fe328aa0f..6dd3f0a28b5e 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -386,6 +386,8 @@ struct sk_buff *udp_gro_receive(struct list_head *head,
struct sk_buff *skb,
NAPI_GRO_CB(p)->same_flow = 0;
continue;
}
+
+ /* TODO: for UDP_GRO: match size */
}
skb_gro_pull(skb, sizeof(struct udphdr)); /* pull encapsulating udp
header */
@@ -437,11 +439,6 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff,
uh->len = newlen;
- /* Set encapsulation before calling into inner gro_complete() functions
- * to make them set up the inner offsets.
- */
- skb->encapsulation = 1;
-
rcu_read_lock();
sk = (*lookup)(skb, uh->source, uh->dest);
if (sk && udp_sk(sk)->gro_complete)
@@ -462,11 +459,11 @@ static int udp4_gro_complete(struct sk_buff *skb, int
nhoff)
struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
if (uh->check) {
- skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
+ skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_L4;
uh->check = ~udp_v4_check(skb->len - nhoff, iph->saddr,
iph->daddr, 0);
} else {
- skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL;
+ skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_L4;
}
return udp_gro_complete(skb, nhoff, udp4_lib_lookup_skb);
--
2.19.0.397.gdd90340f6a-goog
