diff --git a/include/net/gro.h b/include/net/gro.h index 5df8bf318197..f13634b1f4c1 100644 --- a/include/net/gro.h +++ b/include/net/gro.h @@ -36,15 +36,15 @@ struct napi_gro_cb { /* This is non-zero if the packet cannot be merged with the new skb. */ u16 flush; - /* Save the IP ID here and check when we get to the transport layer */ - u16 flush_id; - /* Number of segments aggregated. */ u16 count; /* Used in ipv6_gro_receive() and foo-over-udp and esp-in-udp */ u16 proto; + /* used to support CHECKSUM_COMPLETE for tunneling protocols */ + __wsum csum; + /* Used in napi_gro_cb::free */ #define NAPI_GRO_FREE 1 #define NAPI_GRO_FREE_STOLEN_HEAD 2 @@ -75,8 +75,8 @@ struct napi_gro_cb { /* Used in GRE, set in fou/gue_gro_receive */ u8 is_fou:1; - /* Used to determine if flush_id can be ignored */ - u8 is_atomic:1; + /* Used to determine if ipid_offset can be ignored */ + u8 ip_fixedid:1; /* Number of gro_receive callbacks this packet already went through */ u8 recursion_counter:4; @@ -85,9 +85,6 @@ struct napi_gro_cb { u8 is_flist:1; ); - /* used to support CHECKSUM_COMPLETE for tunneling protocols */ - __wsum csum; - /* L3 offsets */ union { struct { @@ -181,12 +178,17 @@ static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen, return ptr; } +static inline int skb_gro_receive_network_offset(const struct sk_buff *skb) +{ + return NAPI_GRO_CB(skb)->network_offsets[NAPI_GRO_CB(skb)->encap_mark]; +} + static inline void *skb_gro_network_header(const struct sk_buff *skb) { if (skb_gro_may_pull(skb, skb_gro_offset(skb))) - return skb_gro_header_fast(skb, skb_network_offset(skb)); + return skb_gro_header_fast(skb, skb_gro_receive_network_offset(skb)); - return skb_network_header(skb); + return skb->data + skb_gro_receive_network_offset(skb); } static inline __wsum inet_gro_compute_pseudo(const struct sk_buff *skb, @@ -437,6 +439,69 @@ static inline __wsum ip6_gro_compute_pseudo(const struct sk_buff *skb, skb_gro_len(skb), proto, 0)); } +static inline int inet_gro_flush(const struct iphdr *iph, const struct iphdr *iph2, + struct sk_buff *p, bool outer) +{ + const u32 id = ntohl(*(__be32 *)&iph->id); + 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; + int flush; + + /* All fields must match except length and checksum. */ + flush = (iph->ttl ^ iph2->ttl) | (iph->tos ^ iph2->tos) | (df ^ (id2 & IP_DF)); + + if (flush | (outer && df)) + return flush; + + /* 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) + NAPI_GRO_CB(p)->ip_fixedid = true; + + return ipid_offset ^ (count * !NAPI_GRO_CB(p)->ip_fixedid); +} + +static inline int ipv6_gro_flush(const struct ipv6hdr *iph, const struct ipv6hdr *iph2) +{ + /* */ + __be32 first_word = *(__be32 *)iph ^ *(__be32 *)iph2; + + /* Flush if Traffic Class fields are different. */ + return !!((first_word & htonl(0x0FF00000)) | + (__force __be32)(iph->hop_limit ^ iph2->hop_limit)); +} + +static inline int __gro_receive_network_flush(const void *th, const void *th2, + struct sk_buff *p, const u16 diff, + bool outer) +{ + const void *nh = th - diff; + const void *nh2 = th2 - diff; + + if (((struct iphdr *)nh)->version == 6) + return ipv6_gro_flush(nh, nh2); + else + return inet_gro_flush(nh, nh2, p, outer); +} + +static inline int gro_receive_network_flush(const void *th, const void *th2, + struct sk_buff *p) +{ + const bool encap_mark = NAPI_GRO_CB(p)->encap_mark; + int off = skb_transport_offset(p); + int flush; + + flush = __gro_receive_network_flush(th, th2, p, off - NAPI_GRO_CB(p)->network_offset, encap_mark); + if (encap_mark) + flush |= __gro_receive_network_flush(th, th2, p, off - NAPI_GRO_CB(p)->inner_network_offset, false); + + return flush; +} + int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb); int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb); diff --git a/net/core/gro.c b/net/core/gro.c index e2f84947fb74..b3b43de1a650 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -358,8 +358,6 @@ static void gro_list_prepare(const struct list_head *head, list_for_each_entry(p, head, list) { unsigned long diffs; - NAPI_GRO_CB(p)->flush = 0; - if (hash != skb_get_hash_raw(p)) { NAPI_GRO_CB(p)->same_flow = 0; continue; @@ -499,7 +497,6 @@ found_ptype: sizeof(u32))); /* Avoid slow unaligned acc */ *(u32 *)&NAPI_GRO_CB(skb)->zeroed = 0; NAPI_GRO_CB(skb)->flush = skb_has_frag_list(skb); - NAPI_GRO_CB(skb)->is_atomic = 1; NAPI_GRO_CB(skb)->count = 1; if (unlikely(skb_is_gso(skb))) { NAPI_GRO_CB(skb)->count = skb_shinfo(skb)->gso_segs; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index a7bad18bc8b5..44564d009e95 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1482,7 +1482,6 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb) struct sk_buff *p; unsigned int hlen; unsigned int off; - unsigned int id; int flush = 1; int proto; @@ -1508,13 +1507,10 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb) goto out; NAPI_GRO_CB(skb)->proto = proto; - id = ntohl(*(__be32 *)&iph->id); - flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF)); - id >>= 16; + flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (ntohl(*(__be32 *)&iph->id) & ~IP_DF)); list_for_each_entry(p, head, list) { struct iphdr *iph2; - u16 flush_id; if (!NAPI_GRO_CB(p)->same_flow) continue; @@ -1531,48 +1527,9 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb) NAPI_GRO_CB(p)->same_flow = 0; continue; } - - /* All fields must match except length and checksum. */ - NAPI_GRO_CB(p)->flush |= - (iph->ttl ^ iph2->ttl) | - (iph->tos ^ iph2->tos) | - ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF)); - - NAPI_GRO_CB(p)->flush |= flush; - - /* We need to store of the IP ID check to be included later - * when we can verify that this packet does in fact belong - * to a given flow. - */ - flush_id = (u16)(id - ntohs(iph2->id)); - - /* This bit of code makes it much easier for us to identify - * the cases where we are doing atomic vs non-atomic IP ID - * checks. Specifically an atomic check can return IP ID - * values 0 - 0xFFFF, while a non-atomic check can only - * return 0 or 0xFFFF. - */ - if (!NAPI_GRO_CB(p)->is_atomic || - !(iph->frag_off & htons(IP_DF))) { - flush_id ^= NAPI_GRO_CB(p)->count; - flush_id = flush_id ? 0xFFFF : 0; - } - - /* If the previous IP ID value was based on an atomic - * datagram we can overwrite the value and ignore it. - */ - if (NAPI_GRO_CB(skb)->is_atomic) - NAPI_GRO_CB(p)->flush_id = flush_id; - else - NAPI_GRO_CB(p)->flush_id |= flush_id; } - NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF)); NAPI_GRO_CB(skb)->flush |= flush; - skb_set_network_header(skb, off); - /* The above will be needed by the transport layer if there is one - * immediately following this IP hdr. - */ NAPI_GRO_CB(skb)->inner_network_offset = off; /* Note : No need to call skb_gro_postpull_rcsum() here, diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c index c90704befd7b..4b791e74529e 100644 --- a/net/ipv4/tcp_offload.c +++ b/net/ipv4/tcp_offload.c @@ -313,10 +313,8 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb, if (!p) goto out_check_final; - /* Include the IP ID check below from the inner most IP hdr */ th2 = tcp_hdr(p); - flush = NAPI_GRO_CB(p)->flush; - flush |= (__force int)(flags & TCP_FLAG_CWR); + flush = (__force int)(flags & TCP_FLAG_CWR); flush |= (__force int)((flags ^ tcp_flag_word(th2)) & ~(TCP_FLAG_CWR | TCP_FLAG_FIN | TCP_FLAG_PSH)); flush |= (__force int)(th->ack_seq ^ th2->ack_seq); @@ -324,16 +322,7 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb, flush |= *(u32 *)((u8 *)th + i) ^ *(u32 *)((u8 *)th2 + i); - /* When we receive our second frame we can made a decision on if we - * continue this flow as an atomic flow with a fixed ID or if we use - * an incrementing ID. - */ - if (NAPI_GRO_CB(p)->flush_id != 1 || - NAPI_GRO_CB(p)->count != 1 || - !NAPI_GRO_CB(p)->is_atomic) - flush |= NAPI_GRO_CB(p)->flush_id; - else - NAPI_GRO_CB(p)->is_atomic = false; + flush |= gro_receive_network_flush(th, th2, p); mss = skb_shinfo(p)->gso_size; @@ -463,7 +452,8 @@ flush: INDIRECT_CALLABLE_SCOPE int tcp4_gro_complete(struct sk_buff *skb, int thoff) { - const struct iphdr *iph = ip_hdr(skb); + const u16 offset = NAPI_GRO_CB(skb)->network_offsets[skb->encapsulation]; + const struct iphdr *iph = (struct iphdr *)(skb->data + offset); struct tcphdr *th = tcp_hdr(skb); if (unlikely(NAPI_GRO_CB(skb)->is_flist)) { @@ -479,7 +469,7 @@ INDIRECT_CALLABLE_SCOPE int tcp4_gro_complete(struct sk_buff *skb, int thoff) iph->daddr, 0); skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4 | - (NAPI_GRO_CB(skb)->is_atomic * SKB_GSO_TCP_FIXEDID); + (NAPI_GRO_CB(skb)->ip_fixedid * SKB_GSO_TCP_FIXEDID); tcp_gro_complete(skb); return 0; diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index f6d3c442e260..59448a2dbf2c 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -478,14 +478,7 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head, return p; } - flush = NAPI_GRO_CB(p)->flush; - - if (NAPI_GRO_CB(p)->flush_id != 1 || - NAPI_GRO_CB(p)->count != 1 || - !NAPI_GRO_CB(p)->is_atomic) - flush |= NAPI_GRO_CB(p)->flush_id; - else - NAPI_GRO_CB(p)->is_atomic = false; + flush = gro_receive_network_flush(uh, uh2, p); /* Terminate the flow on len mismatch or if it grow "too much". * Under small packet flood GRO count could elsewhere grow a lot diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index c8b909a9904f..bd5aff97d8b1 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -67,7 +67,7 @@ static int ipv6_gro_pull_exthdrs(struct sk_buff *skb, int off, int proto) off += len; } - skb_gro_pull(skb, off - skb_network_offset(skb)); + skb_gro_pull(skb, off - skb_gro_receive_network_offset(skb)); return proto; } @@ -236,7 +236,6 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head, if (unlikely(!iph)) goto out; - skb_set_network_header(skb, off); NAPI_GRO_CB(skb)->inner_network_offset = off; flush += ntohs(iph->payload_len) != skb->len - hlen; @@ -260,7 +259,7 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head, NAPI_GRO_CB(skb)->proto = proto; flush--; - nlen = skb_network_header_len(skb); + nlen = skb_gro_offset(skb) - off; list_for_each_entry(p, head, list) { const struct ipv6hdr *iph2; @@ -291,19 +290,8 @@ not_same_flow: nlen - sizeof(struct ipv6hdr))) goto not_same_flow; } - /* flush if Traffic Class fields are different */ - NAPI_GRO_CB(p)->flush |= !!((first_word & htonl(0x0FF00000)) | - (__force __be32)(iph->hop_limit ^ iph2->hop_limit)); - NAPI_GRO_CB(p)->flush |= flush; - - /* If the previous IP ID value was based on an atomic - * datagram we can overwrite the value and ignore it. - */ - if (NAPI_GRO_CB(skb)->is_atomic) - NAPI_GRO_CB(p)->flush_id = 0; } - NAPI_GRO_CB(skb)->is_atomic = true; NAPI_GRO_CB(skb)->flush |= flush; skb_gro_postpull_rcsum(skb, iph, nlen); diff --git a/net/ipv6/tcpv6_offload.c b/net/ipv6/tcpv6_offload.c index d59f58cbd306..23971903e66d 100644 --- a/net/ipv6/tcpv6_offload.c +++ b/net/ipv6/tcpv6_offload.c @@ -72,7 +72,8 @@ flush: INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, int thoff) { - const struct ipv6hdr *iph = ipv6_hdr(skb); + const u16 offset = NAPI_GRO_CB(skb)->network_offsets[skb->encapsulation]; + const struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + offset); struct tcphdr *th = tcp_hdr(skb); if (unlikely(NAPI_GRO_CB(skb)->is_flist)) { diff --git a/tools/testing/selftests/net/gro.c b/tools/testing/selftests/net/gro.c index 6038b96ecee8..b2184847e388 100644 --- a/tools/testing/selftests/net/gro.c +++ b/tools/testing/selftests/net/gro.c @@ -93,6 +93,7 @@ static bool tx_socket = true; static int tcp_offset = -1; static int total_hdr_len = -1; static int ethhdr_proto = -1; +static const int num_flush_id_cases = 6; static void vlog(const char *fmt, ...) { @@ -620,6 +621,113 @@ static void add_ipv6_exthdr(void *buf, void *optpkt, __u8 exthdr_type, char *ext iph->payload_len = htons(ntohs(iph->payload_len) + MIN_EXTHDR_SIZE); } +static void fix_ip4_checksum(struct iphdr *iph) +{ + iph->check = 0; + iph->check = checksum_fold(iph, sizeof(struct iphdr), 0); +} + +static void send_flush_id_case(int fd, struct sockaddr_ll *daddr, int tcase) +{ + static char buf1[MAX_HDR_LEN + PAYLOAD_LEN]; + static char buf2[MAX_HDR_LEN + PAYLOAD_LEN]; + static char buf3[MAX_HDR_LEN + PAYLOAD_LEN]; + bool send_three = false; + struct iphdr *iph1; + struct iphdr *iph2; + struct iphdr *iph3; + + iph1 = (struct iphdr *)(buf1 + ETH_HLEN); + iph2 = (struct iphdr *)(buf2 + ETH_HLEN); + iph3 = (struct iphdr *)(buf3 + ETH_HLEN); + + create_packet(buf1, 0, 0, PAYLOAD_LEN, 0); + create_packet(buf2, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); + create_packet(buf3, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0); + + switch (tcase) { + case 0: /* DF=1, Incrementing - should coalesce */ + iph1->frag_off |= htons(IP_DF); + iph1->id = htons(8); + + iph2->frag_off |= htons(IP_DF); + iph2->id = htons(9); + break; + + case 1: /* DF=1, Fixed - should coalesce */ + iph1->frag_off |= htons(IP_DF); + iph1->id = htons(8); + + iph2->frag_off |= htons(IP_DF); + iph2->id = htons(8); + break; + + case 2: /* DF=0, Incrementing - should coalesce */ + iph1->frag_off &= ~htons(IP_DF); + iph1->id = htons(8); + + iph2->frag_off &= ~htons(IP_DF); + iph2->id = htons(9); + break; + + case 3: /* DF=0, Fixed - should not coalesce */ + iph1->frag_off &= ~htons(IP_DF); + iph1->id = htons(8); + + iph2->frag_off &= ~htons(IP_DF); + iph2->id = htons(8); + break; + + case 4: /* DF=1, two packets incrementing, and one fixed - should + * coalesce only the first two packets + */ + iph1->frag_off |= htons(IP_DF); + iph1->id = htons(8); + + iph2->frag_off |= htons(IP_DF); + iph2->id = htons(9); + + iph3->frag_off |= htons(IP_DF); + iph3->id = htons(9); + send_three = true; + break; + + case 5: /* DF=1, two packets fixed, and one incrementing - should + * coalesce only the first two packets + */ + iph1->frag_off |= htons(IP_DF); + iph1->id = htons(8); + + iph2->frag_off |= htons(IP_DF); + iph2->id = htons(8); + + iph3->frag_off |= htons(IP_DF); + iph3->id = htons(9); + send_three = true; + break; + } + + fix_ip4_checksum(iph1); + fix_ip4_checksum(iph2); + write_packet(fd, buf1, total_hdr_len + PAYLOAD_LEN, daddr); + write_packet(fd, buf2, total_hdr_len + PAYLOAD_LEN, daddr); + + if (send_three) { + fix_ip4_checksum(iph3); + write_packet(fd, buf3, total_hdr_len + PAYLOAD_LEN, daddr); + } +} + +static void test_flush_id(int fd, struct sockaddr_ll *daddr, char *fin_pkt) +{ + for (int i = 0; i < num_flush_id_cases; i++) { + sleep(1); + send_flush_id_case(fd, daddr, i); + sleep(1); + write_packet(fd, fin_pkt, total_hdr_len, daddr); + } +} + static void send_ipv6_exthdr(int fd, struct sockaddr_ll *daddr, char *ext_data1, char *ext_data2) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; @@ -938,6 +1046,8 @@ static void gro_sender(void) send_fragment4(txfd, &daddr); sleep(1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); + + test_flush_id(txfd, &daddr, fin_pkt); } else if (proto == PF_INET6) { sleep(1); send_fragment6(txfd, &daddr); @@ -1064,6 +1174,34 @@ static void gro_receiver(void) printf("fragmented ip4 doesn't coalesce: "); check_recv_pkts(rxfd, correct_payload, 2); + + /* is_atomic checks */ + printf("DF=1, Incrementing - should coalesce: "); + correct_payload[0] = PAYLOAD_LEN * 2; + check_recv_pkts(rxfd, correct_payload, 1); + + printf("DF=1, Fixed - should coalesce: "); + correct_payload[0] = PAYLOAD_LEN * 2; + check_recv_pkts(rxfd, correct_payload, 1); + + printf("DF=0, Incrementing - should coalesce: "); + 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=1, 2 Incrementing and one fixed - should coalesce only first 2 packets: "); + correct_payload[0] = PAYLOAD_LEN * 2; + correct_payload[1] = PAYLOAD_LEN; + check_recv_pkts(rxfd, correct_payload, 2); + + printf("DF=1, 2 Fixed and one incrementing - should coalesce only first 2 packets: "); + correct_payload[0] = PAYLOAD_LEN * 2; + correct_payload[1] = PAYLOAD_LEN; + check_recv_pkts(rxfd, correct_payload, 2); } else if (proto == PF_INET6) { /* GRO doesn't check for ipv6 hop limit when flushing. * Hence no corresponding test to the ipv4 case.