Currently, packets with fixed IDs will be merged only if their don't-fragment bit is set. Merged packets are re-split into segments before being fragmented, so the result is the same as if the packets weren't merged to begin with. Remove unnecessary don't-fragment checks. Signed-off-by: Richard Gobert --- include/net/gro.h | 5 ++--- net/ipv4/af_inet.c | 3 --- tools/testing/selftests/net/gro.c | 9 ++++----- 3 files changed, 6 insertions(+), 11 deletions(-) diff --git a/include/net/gro.h b/include/net/gro.h index 322c5517f508..691f267b3969 100644 --- a/include/net/gro.h +++ b/include/net/gro.h @@ -448,17 +448,16 @@ static inline int inet_gro_flush(const struct iphdr *iph, const struct iphdr *ip const u32 id2 = ntohl(*(__be32 *)&iph2->id); const u16 ipid_offset = (id >> 16) - (id2 >> 16); const u16 count = NAPI_GRO_CB(p)->count; - const u32 df = id & IP_DF; /* All fields must match except length and checksum. */ - if ((iph->ttl ^ iph2->ttl) | (iph->tos ^ iph2->tos) | (df ^ (id2 & IP_DF))) + if ((iph->ttl ^ iph2->ttl) | (iph->tos ^ iph2->tos) | ((id ^ id2) & IP_DF)) return true; /* When we receive our second frame we can make a decision on if we * continue this flow as an atomic flow with a fixed ID or if we use * an incrementing ID. */ - if (count == 1 && df && !ipid_offset) + if (count == 1 && !ipid_offset) NAPI_GRO_CB(p)->ip_fixedid |= 1 << inner; return ipid_offset ^ (count * !(NAPI_GRO_CB(p)->ip_fixedid & (1 << inner))); diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index fc7a6955fa0a..c0542d9187e2 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1393,10 +1393,7 @@ struct sk_buff *inet_gso_segment(struct sk_buff *skb, segs = ERR_PTR(-EPROTONOSUPPORT); - /* fixed ID is invalid if DF bit is not set */ fixedid = !!(skb_shinfo(skb)->gso_type & (SKB_GSO_TCP_FIXEDID << encap)); - if (fixedid && !(ip_hdr(skb)->frag_off & htons(IP_DF))) - goto out; if (!skb->encapsulation || encap) udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP); diff --git a/tools/testing/selftests/net/gro.c b/tools/testing/selftests/net/gro.c index d5824eadea10..3d4a82a2607c 100644 --- a/tools/testing/selftests/net/gro.c +++ b/tools/testing/selftests/net/gro.c @@ -670,7 +670,7 @@ static void send_flush_id_case(int fd, struct sockaddr_ll *daddr, int tcase) iph2->id = htons(9); break; - case 3: /* DF=0, Fixed - should not coalesce */ + case 3: /* DF=0, Fixed - should coalesce */ iph1->frag_off &= ~htons(IP_DF); iph1->id = htons(8); @@ -1188,10 +1188,9 @@ static void gro_receiver(void) correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 1); - printf("DF=0, Fixed - should not coalesce: "); - correct_payload[0] = PAYLOAD_LEN; - correct_payload[1] = PAYLOAD_LEN; - check_recv_pkts(rxfd, correct_payload, 2); + printf("DF=0, Fixed - should coalesce: "); + correct_payload[0] = PAYLOAD_LEN * 2; + check_recv_pkts(rxfd, correct_payload, 1); printf("DF=1, 2 Incrementing and one fixed - should coalesce only first 2 packets: "); correct_payload[0] = PAYLOAD_LEN * 2; -- 2.36.1