/* SPDX-License-Identifier: GPL-2.0 */
/* AF_XDP internal functions
 * Copyright(c) 2018 Intel Corporation.
 */

#ifndef _LINUX_XDP_SOCK_H
#define _LINUX_XDP_SOCK_H

#include <linux/bpf.h>
#include <linux/workqueue.h>
#include <linux/if_xdp.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <net/sock.h>

#define XDP_UMEM_SG_FLAG (1 << 1)

struct net_device;
struct xsk_queue;
struct xdp_buff;

struct xdp_umem {
    void *addrs;
    u64 size;
    u32 headroom;
    u32 chunk_size;
    u32 chunks;
    u32 npgs;
    struct user_struct *user;
    refcount_t users;
    u8 flags;
    bool zc;
    struct page **pgs;
    int id;
    struct list_head xsk_dma_list;
    struct work_struct work;
};

struct xsk_map {
    struct bpf_map map;
    spinlock_t lock; /* Synchronize map updates */
    atomic_t count;
    struct xdp_sock __rcu *xsk_map[];
};

struct xdp_sock {
    /* struct sock must be the first member of struct xdp_sock */
    struct sock sk;
    struct xsk_queue *rx ____cacheline_aligned_in_smp;
    struct net_device *dev;
    struct xdp_umem *umem;
    struct list_head flush_node;
    struct xsk_buff_pool *pool;
    u16 queue_id;
    bool zc;
    bool sg;
    enum {
        XSK_READY = 0,
        XSK_BOUND,
        XSK_UNBOUND,
    } state;

    struct xsk_queue *tx ____cacheline_aligned_in_smp;
    struct list_head tx_list;

    /* Statistics */
    u64 rx_dropped;
    u64 rx_queue_full;

    /* When __xsk_generic_xmit() must return before it sees the EOP descriptor for the current
     * packet, the partially built skb is saved here so that packet building can resume in next
     * call of __xsk_generic_xmit().
     */
    struct sk_buff *skb;

    struct list_head map_list;
    /* Protects map_list */
    spinlock_t map_list_lock;
    /* Protects multiple processes in the control path */
    struct mutex mutex;
    struct xsk_queue *fq_tmp; /* Only as tmp storage before bind */
    struct xsk_queue *cq_tmp; /* Only as tmp storage before bind */
};

#ifdef CONFIG_XDP_SOCKETS

int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp);
void __xsk_map_flush(void);

#else

static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
{
    return -ENOTSUPP;
}

static inline int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp)
{
    return -EOPNOTSUPP;
}

static inline void __xsk_map_flush(void)
{
}

#endif /* CONFIG_XDP_SOCKETS */

#endif /* _LINUX_XDP_SOCK_H */