1 /* SPDX-License-Identifier: GPL-2.0 2 * 3 * Copyright (c) 2019 Facebook 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of version 2 of the GNU General Public 7 * License as published by the Free Software Foundation. 8 * 9 * Include file for sample Host Bandwidth Manager (HBM) BPF programs 10 */ 11 #define KBUILD_MODNAME "foo" 12 #include <stddef.h> 13 #include <stdbool.h> 14 #include <uapi/linux/bpf.h> 15 #include <uapi/linux/if_ether.h> 16 #include <uapi/linux/if_packet.h> 17 #include <uapi/linux/ip.h> 18 #include <uapi/linux/ipv6.h> 19 #include <uapi/linux/in.h> 20 #include <uapi/linux/tcp.h> 21 #include <uapi/linux/filter.h> 22 #include <uapi/linux/pkt_cls.h> 23 #include <net/ipv6.h> 24 #include <net/inet_ecn.h> 25 #include "bpf_endian.h" 26 #include "bpf_helpers.h" 27 #include "hbm.h" 28 29 #define DROP_PKT 0 30 #define ALLOW_PKT 1 31 #define TCP_ECN_OK 1 32 33 #ifndef HBM_DEBUG // Define HBM_DEBUG to enable debugging 34 #undef bpf_printk 35 #define bpf_printk(fmt, ...) 36 #endif 37 38 #define INITIAL_CREDIT_PACKETS 100 39 #define MAX_BYTES_PER_PACKET 1500 40 #define MARK_THRESH (40 * MAX_BYTES_PER_PACKET) 41 #define DROP_THRESH (80 * 5 * MAX_BYTES_PER_PACKET) 42 #define LARGE_PKT_DROP_THRESH (DROP_THRESH - (15 * MAX_BYTES_PER_PACKET)) 43 #define MARK_REGION_SIZE (LARGE_PKT_DROP_THRESH - MARK_THRESH) 44 #define LARGE_PKT_THRESH 120 45 #define MAX_CREDIT (100 * MAX_BYTES_PER_PACKET) 46 #define INIT_CREDIT (INITIAL_CREDIT_PACKETS * MAX_BYTES_PER_PACKET) 47 48 // rate in bytes per ns << 20 49 #define CREDIT_PER_NS(delta, rate) ((((u64)(delta)) * (rate)) >> 20) 50 51 struct bpf_map_def SEC("maps") queue_state = { 52 .type = BPF_MAP_TYPE_CGROUP_STORAGE, 53 .key_size = sizeof(struct bpf_cgroup_storage_key), 54 .value_size = sizeof(struct hbm_vqueue), 55 }; 56 BPF_ANNOTATE_KV_PAIR(queue_state, struct bpf_cgroup_storage_key, 57 struct hbm_vqueue); 58 59 struct bpf_map_def SEC("maps") queue_stats = { 60 .type = BPF_MAP_TYPE_ARRAY, 61 .key_size = sizeof(u32), 62 .value_size = sizeof(struct hbm_queue_stats), 63 .max_entries = 1, 64 }; 65 BPF_ANNOTATE_KV_PAIR(queue_stats, int, struct hbm_queue_stats); 66 67 struct hbm_pkt_info { 68 bool is_ip; 69 bool is_tcp; 70 short ecn; 71 }; 72 73 static __always_inline void hbm_get_pkt_info(struct __sk_buff *skb, 74 struct hbm_pkt_info *pkti) 75 { 76 struct iphdr iph; 77 struct ipv6hdr *ip6h; 78 79 bpf_skb_load_bytes(skb, 0, &iph, 12); 80 if (iph.version == 6) { 81 ip6h = (struct ipv6hdr *)&iph; 82 pkti->is_ip = true; 83 pkti->is_tcp = (ip6h->nexthdr == 6); 84 pkti->ecn = (ip6h->flow_lbl[0] >> 4) & INET_ECN_MASK; 85 } else if (iph.version == 4) { 86 pkti->is_ip = true; 87 pkti->is_tcp = (iph.protocol == 6); 88 pkti->ecn = iph.tos & INET_ECN_MASK; 89 } else { 90 pkti->is_ip = false; 91 pkti->is_tcp = false; 92 pkti->ecn = 0; 93 } 94 } 95 96 static __always_inline void hbm_init_vqueue(struct hbm_vqueue *qdp, int rate) 97 { 98 bpf_printk("Initializing queue_state, rate:%d\n", rate * 128); 99 qdp->lasttime = bpf_ktime_get_ns(); 100 qdp->credit = INIT_CREDIT; 101 qdp->rate = rate * 128; 102 } 103 104 static __always_inline void hbm_update_stats(struct hbm_queue_stats *qsp, 105 int len, 106 unsigned long long curtime, 107 bool congestion_flag, 108 bool drop_flag) 109 { 110 if (qsp != NULL) { 111 // Following is needed for work conserving 112 __sync_add_and_fetch(&(qsp->bytes_total), len); 113 if (qsp->stats) { 114 // Optionally update statistics 115 if (qsp->firstPacketTime == 0) 116 qsp->firstPacketTime = curtime; 117 qsp->lastPacketTime = curtime; 118 __sync_add_and_fetch(&(qsp->pkts_total), 1); 119 if (congestion_flag || drop_flag) { 120 __sync_add_and_fetch(&(qsp->pkts_marked), 1); 121 __sync_add_and_fetch(&(qsp->bytes_marked), len); 122 } 123 if (drop_flag) { 124 __sync_add_and_fetch(&(qsp->pkts_dropped), 1); 125 __sync_add_and_fetch(&(qsp->bytes_dropped), 126 len); 127 } 128 } 129 } 130 } 131