From 04dd17822334871b23ea2862f7798fb0e0007777 Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Sat, 11 May 2024 08:53:19 +0000 Subject: [PATCH] change otg to host mode --- kernel/net/ipv4/udp_offload.c | 287 +++++++++++++++++++++++++++++++++++++++++++++++++------- 1 files changed, 248 insertions(+), 39 deletions(-) diff --git a/kernel/net/ipv4/udp_offload.c b/kernel/net/ipv4/udp_offload.c index 2d22d39..f4b8e56 100644 --- a/kernel/net/ipv4/udp_offload.c +++ b/kernel/net/ipv4/udp_offload.c @@ -1,11 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * IPV4 GSO/GRO offload support * Linux INET implementation - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. * * UDPv4 GSO support */ @@ -13,6 +9,7 @@ #include <linux/skbuff.h> #include <net/udp.h> #include <net/protocol.h> +#include <net/inet_common.h> static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, netdev_features_t features, @@ -187,8 +184,81 @@ } EXPORT_SYMBOL(skb_udp_tunnel_segment); +static void __udpv4_gso_segment_csum(struct sk_buff *seg, + __be32 *oldip, __be32 *newip, + __be16 *oldport, __be16 *newport) +{ + struct udphdr *uh; + struct iphdr *iph; + + if (*oldip == *newip && *oldport == *newport) + return; + + uh = udp_hdr(seg); + iph = ip_hdr(seg); + + if (uh->check) { + inet_proto_csum_replace4(&uh->check, seg, *oldip, *newip, + true); + inet_proto_csum_replace2(&uh->check, seg, *oldport, *newport, + false); + if (!uh->check) + uh->check = CSUM_MANGLED_0; + } + *oldport = *newport; + + csum_replace4(&iph->check, *oldip, *newip); + *oldip = *newip; +} + +static struct sk_buff *__udpv4_gso_segment_list_csum(struct sk_buff *segs) +{ + struct sk_buff *seg; + struct udphdr *uh, *uh2; + struct iphdr *iph, *iph2; + + seg = segs; + uh = udp_hdr(seg); + iph = ip_hdr(seg); + + if ((udp_hdr(seg)->dest == udp_hdr(seg->next)->dest) && + (udp_hdr(seg)->source == udp_hdr(seg->next)->source) && + (ip_hdr(seg)->daddr == ip_hdr(seg->next)->daddr) && + (ip_hdr(seg)->saddr == ip_hdr(seg->next)->saddr)) + return segs; + + while ((seg = seg->next)) { + uh2 = udp_hdr(seg); + iph2 = ip_hdr(seg); + + __udpv4_gso_segment_csum(seg, + &iph2->saddr, &iph->saddr, + &uh2->source, &uh->source); + __udpv4_gso_segment_csum(seg, + &iph2->daddr, &iph->daddr, + &uh2->dest, &uh->dest); + } + + return segs; +} + +static struct sk_buff *__udp_gso_segment_list(struct sk_buff *skb, + netdev_features_t features, + bool is_ipv6) +{ + unsigned int mss = skb_shinfo(skb)->gso_size; + + skb = skb_segment_list(skb, features, skb_mac_header_len(skb)); + if (IS_ERR(skb)) + return skb; + + udp_hdr(skb)->len = htons(sizeof(struct udphdr) + mss); + + return is_ipv6 ? skb : __udpv4_gso_segment_list_csum(skb); +} + struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb, - netdev_features_t features) + netdev_features_t features, bool is_ipv6) { struct sock *sk = gso_skb->sk; unsigned int sum_truesize = 0; @@ -198,6 +268,9 @@ bool copy_dtor; __sum16 check; __be16 newlen; + + if (skb_shinfo(gso_skb)->gso_type & SKB_GSO_FRAGLIST) + return __udp_gso_segment_list(gso_skb, features, is_ipv6); mss = skb_shinfo(gso_skb)->gso_size; if (gso_skb->len <= sizeof(*uh) + mss) @@ -211,7 +284,7 @@ gso_skb->destructor = NULL; segs = skb_segment(gso_skb, features); - if (unlikely(IS_ERR_OR_NULL(segs))) { + if (IS_ERR_OR_NULL(segs)) { if (copy_dtor) gso_skb->destructor = sock_wfree; return segs; @@ -311,7 +384,7 @@ goto out; if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) - return __udp_gso_segment(skb, features); + return __udp_gso_segment(skb, features, false); mss = skb_shinfo(skb)->gso_size; if (unlikely(skb->len <= mss)) @@ -348,33 +421,116 @@ return segs; } +#define UDP_GRO_CNT_MAX 64 +static struct sk_buff *udp_gro_receive_segment(struct list_head *head, + struct sk_buff *skb) +{ + struct udphdr *uh = udp_gro_udphdr(skb); + struct sk_buff *pp = NULL; + struct udphdr *uh2; + struct sk_buff *p; + unsigned int ulen; + int ret = 0; + + /* requires non zero csum, for symmetry with GSO */ + if (!uh->check) { + NAPI_GRO_CB(skb)->flush = 1; + return NULL; + } + + /* Do not deal with padded or malicious packets, sorry ! */ + ulen = ntohs(uh->len); + if (ulen <= sizeof(*uh) || ulen != skb_gro_len(skb)) { + NAPI_GRO_CB(skb)->flush = 1; + return NULL; + } + /* pull encapsulating udp header */ + skb_gro_pull(skb, sizeof(struct udphdr)); + + list_for_each_entry(p, head, list) { + if (!NAPI_GRO_CB(p)->same_flow) + continue; + + uh2 = udp_hdr(p); + + /* Match ports only, as csum is always non zero */ + if ((*(u32 *)&uh->source != *(u32 *)&uh2->source)) { + NAPI_GRO_CB(p)->same_flow = 0; + continue; + } + + if (NAPI_GRO_CB(skb)->is_flist != NAPI_GRO_CB(p)->is_flist) { + NAPI_GRO_CB(skb)->flush = 1; + return p; + } + + /* Terminate the flow on len mismatch or if it grow "too much". + * Under small packet flood GRO count could elsewhere grow a lot + * leading to excessive truesize values. + * On len mismatch merge the first packet shorter than gso_size, + * otherwise complete the GRO packet. + */ + if (ulen > ntohs(uh2->len)) { + pp = p; + } else { + if (NAPI_GRO_CB(skb)->is_flist) { + if (!pskb_may_pull(skb, skb_gro_offset(skb))) { + NAPI_GRO_CB(skb)->flush = 1; + return NULL; + } + if ((skb->ip_summed != p->ip_summed) || + (skb->csum_level != p->csum_level)) { + NAPI_GRO_CB(skb)->flush = 1; + return NULL; + } + ret = skb_gro_receive_list(p, skb); + } else { + skb_gro_postpull_rcsum(skb, uh, + sizeof(struct udphdr)); + + ret = skb_gro_receive(p, skb); + } + } + + if (ret || ulen != ntohs(uh2->len) || + NAPI_GRO_CB(p)->count >= UDP_GRO_CNT_MAX) + pp = p; + + return pp; + } + + /* mismatch, but we never need to flush */ + return NULL; +} + struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb, - struct udphdr *uh, udp_lookup_t lookup) + struct udphdr *uh, struct sock *sk) { struct sk_buff *pp = NULL; struct sk_buff *p; struct udphdr *uh2; unsigned int off = skb_gro_offset(skb); int flush = 1; - struct sock *sk; - if (NAPI_GRO_CB(skb)->encap_mark || + NAPI_GRO_CB(skb)->is_flist = 0; + if (skb->dev->features & NETIF_F_GRO_FRAGLIST) + NAPI_GRO_CB(skb)->is_flist = sk ? !udp_sk(sk)->gro_enabled: 1; + + if ((sk && udp_sk(sk)->gro_enabled) || NAPI_GRO_CB(skb)->is_flist) { + pp = call_gro_receive(udp_gro_receive_segment, head, skb); + return pp; + } + + if (!sk || NAPI_GRO_CB(skb)->encap_mark || (uh->check && skb->ip_summed != CHECKSUM_PARTIAL && NAPI_GRO_CB(skb)->csum_cnt == 0 && - !NAPI_GRO_CB(skb)->csum_valid)) + !NAPI_GRO_CB(skb)->csum_valid) || + !udp_sk(sk)->gro_receive) goto out; /* mark that this skb passed once through the tunnel gro layer */ NAPI_GRO_CB(skb)->encap_mark = 1; - rcu_read_lock(); - sk = (*lookup)(skb, uh->source, uh->dest); - - if (sk && udp_sk(sk)->gro_receive) - goto unflush; - goto out_unlock; - -unflush: flush = 0; list_for_each_entry(p, head, list) { @@ -397,18 +553,28 @@ skb_gro_postpull_rcsum(skb, uh, sizeof(struct udphdr)); pp = call_gro_receive_sk(udp_sk(sk)->gro_receive, sk, head, skb); -out_unlock: - rcu_read_unlock(); out: skb_gro_flush_final(skb, pp, flush); return pp; } EXPORT_SYMBOL(udp_gro_receive); -static struct sk_buff *udp4_gro_receive(struct list_head *head, - struct sk_buff *skb) +static struct sock *udp4_gro_lookup_skb(struct sk_buff *skb, __be16 sport, + __be16 dport) +{ + const struct iphdr *iph = skb_gro_network_header(skb); + + return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport, + iph->daddr, dport, inet_iif(skb), + inet_sdif(skb), &udp_table, NULL); +} + +INDIRECT_CALLABLE_SCOPE +struct sk_buff *udp4_gro_receive(struct list_head *head, struct sk_buff *skb) { struct udphdr *uh = udp_gro_udphdr(skb); + struct sock *sk = NULL; + struct sk_buff *pp; if (unlikely(!uh)) goto flush; @@ -421,15 +587,39 @@ inet_gro_compute_pseudo)) goto flush; else if (uh->check) - skb_gro_checksum_try_convert(skb, IPPROTO_UDP, uh->check, + skb_gro_checksum_try_convert(skb, IPPROTO_UDP, inet_gro_compute_pseudo); skip: NAPI_GRO_CB(skb)->is_ipv6 = 0; - return udp_gro_receive(head, skb, uh, udp4_lib_lookup_skb); + rcu_read_lock(); + + if (static_branch_unlikely(&udp_encap_needed_key)) + sk = udp4_gro_lookup_skb(skb, uh->source, uh->dest); + + pp = udp_gro_receive(head, skb, uh, sk); + rcu_read_unlock(); + return pp; flush: NAPI_GRO_CB(skb)->flush = 1; return NULL; +} + +static int udp_gro_complete_segment(struct sk_buff *skb) +{ + struct udphdr *uh = udp_hdr(skb); + + skb->csum_start = (unsigned char *)uh - skb->head; + skb->csum_offset = offsetof(struct udphdr, check); + skb->ip_summed = CHECKSUM_PARTIAL; + + skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; + skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_L4; + + if (skb->encapsulation) + skb->inner_transport_header = skb->transport_header; + + return 0; } int udp_gro_complete(struct sk_buff *skb, int nhoff, @@ -442,16 +632,22 @@ 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) + sk = INDIRECT_CALL_INET(lookup, udp6_lib_lookup_skb, + udp4_lib_lookup_skb, skb, uh->source, uh->dest); + if (sk && udp_sk(sk)->gro_complete) { + skb_shinfo(skb)->gso_type = uh->check ? SKB_GSO_UDP_TUNNEL_CSUM + : SKB_GSO_UDP_TUNNEL; + + /* Set encapsulation before calling into inner gro_complete() + * functions to make them set up the inner offsets. + */ + skb->encapsulation = 1; err = udp_sk(sk)->gro_complete(sk, skb, nhoff + sizeof(struct udphdr)); + } else { + err = udp_gro_complete_segment(skb); + } rcu_read_unlock(); if (skb->remcsum_offload) @@ -461,18 +657,31 @@ } EXPORT_SYMBOL(udp_gro_complete); -static int udp4_gro_complete(struct sk_buff *skb, int nhoff) +INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff) { const struct iphdr *iph = ip_hdr(skb); struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); - if (uh->check) { - skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM; + if (NAPI_GRO_CB(skb)->is_flist) { + uh->len = htons(skb->len - nhoff); + + skb_shinfo(skb)->gso_type |= (SKB_GSO_FRAGLIST|SKB_GSO_UDP_L4); + skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; + + if (skb->ip_summed == CHECKSUM_UNNECESSARY) { + if (skb->csum_level < SKB_MAX_CSUM_LEVEL) + skb->csum_level++; + } else { + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->csum_level = 0; + } + + return 0; + } + + if (uh->check) uh->check = ~udp_v4_check(skb->len - nhoff, iph->saddr, iph->daddr, 0); - } else { - skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL; - } return udp_gro_complete(skb, nhoff, udp4_lib_lookup_skb); } -- Gitblit v1.6.2