/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2026 Meta Platforms, Inc. and affiliates. */

#ifndef XDP_LB_BENCH_COMMON_H
#define XDP_LB_BENCH_COMMON_H

#define F_IPV6          (1 << 0)
#define F_LRU_BYPASS    (1 << 1)

#define CH_RING_SIZE    65537           /* per-VIP consistent hash ring slots */
#define MAX_VIPS        16
#define CH_RINGS_SIZE   (MAX_VIPS * CH_RING_SIZE)
#define MAX_REALS       512
#define DEFAULT_LRU_SIZE 100000         /* connection tracking cache size */
#define ONE_SEC         1000000000U     /* 1 sec in nanosec */
#define MAX_CONN_RATE   100000000       /* high enough to never trigger in bench */
#define LRU_UDP_TIMEOUT 30000000000ULL  /* 30 sec in nanosec */
#define PCKT_FRAGMENTED 0x3FFF
#define KNUTH_HASH_MULT 2654435761U
#define IPIP_V4_PREFIX  4268            /* 172.16/12 in network order */
#define IPIP_V6_PREFIX1 1               /* 0100::/64 (RFC 6666 discard) */
#define IPIP_V6_PREFIX2 0
#define IPIP_V6_PREFIX3 0

/* Stats indices (0..MAX_VIPS-1 are per-VIP packet/byte counters) */
#define STATS_LRU       (MAX_VIPS + 0)  /* v1: total VIP packets, v2: LRU misses */
#define STATS_XDP_TX    (MAX_VIPS + 1)
#define STATS_XDP_PASS  (MAX_VIPS + 2)
#define STATS_XDP_DROP  (MAX_VIPS + 3)
#define STATS_NEW_CONN  (MAX_VIPS + 4)  /* v1: conn count, v2: last reset ts */
#define STATS_LRU_MISS  (MAX_VIPS + 5)  /* v1: TCP LRU misses */
#define STATS_SIZE      (MAX_VIPS + 6)

#ifdef __BPF__
#define lb_htons(x)     bpf_htons(x)
#define LB_INLINE       static __always_inline
#else
#define lb_htons(x)     htons(x)
#define LB_INLINE       static inline
#endif

LB_INLINE __be32 create_encap_ipv4_src(__u16 port, __be32 src)
{
        __u32 ip_suffix = lb_htons(port);

        ip_suffix <<= 16;
        ip_suffix ^= src;
        return (0xFFFF0000 & ip_suffix) | IPIP_V4_PREFIX;
}

LB_INLINE void create_encap_ipv6_src(__u16 port, __be32 src, __be32 *saddr)
{
        saddr[0] = IPIP_V6_PREFIX1;
        saddr[1] = IPIP_V6_PREFIX2;
        saddr[2] = IPIP_V6_PREFIX3;
        saddr[3] = src ^ port;
}

struct flow_key {
        union {
                __be32 src;
                __be32 srcv6[4];
        };
        union {
                __be32 dst;
                __be32 dstv6[4];
        };
        union {
                __u32 ports;
                __u16 port16[2];
        };
        __u8 proto;
        __u8 pad[3];
};

struct vip_definition {
        union {
                __be32 vip;
                __be32 vipv6[4];
        };
        __u16 port;
        __u8 proto;
        __u8 pad;
};

struct vip_meta {
        __u32 flags;
        __u32 vip_num;
};

struct real_pos_lru {
        __u32 pos;
        __u64 atime;
};

struct real_definition {
        __be32 dst;
        __be32 dstv6[4];
        __u8   flags;
};

struct lb_stats {
        __u64 v1;
        __u64 v2;
};

struct ctl_value {
        __u8 mac[6];
        __u8 pad[2];
};

#endif /* XDP_LB_BENCH_COMMON_H */