/*
 * Copyright (C) 2017 Netronome Systems, Inc.
 *
 * This software is licensed under the GNU General License Version 2,
 * June 1991 as shown in the file COPYING in the top-level directory of this
 * source tree.
 *
 * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
 * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
 * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
 * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
 */

#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/u64_stats_sync.h>
#include <net/devlink.h>
#include <net/xdp.h>

#define DRV_NAME        "netdevsim"

#define NSIM_XDP_MAX_MTU        4000

#define NSIM_EA(extack, msg)    NL_SET_ERR_MSG_MOD((extack), msg)

#define NSIM_IPSEC_MAX_SA_COUNT         33
#define NSIM_IPSEC_VALID                BIT(31)

struct nsim_sa {
        struct xfrm_state *xs;
        __be32 ipaddr[4];
        u32 key[4];
        u32 salt;
        bool used;
        bool crypt;
        bool rx;
};

struct nsim_ipsec {
        struct nsim_sa sa[NSIM_IPSEC_MAX_SA_COUNT];
        struct dentry *pfile;
        u32 count;
        u32 tx;
        u32 ok;
};

struct netdevsim {
        struct net_device *netdev;
        struct nsim_dev *nsim_dev;
        struct nsim_dev_port *nsim_dev_port;

        u64 tx_packets;
        u64 tx_bytes;
        struct u64_stats_sync syncp;

        struct nsim_bus_dev *nsim_bus_dev;

        struct bpf_prog *bpf_offloaded;
        u32 bpf_offloaded_id;

        struct xdp_attachment_info xdp;
        struct xdp_attachment_info xdp_hw;

        bool bpf_tc_accept;
        bool bpf_tc_non_bound_accept;
        bool bpf_xdpdrv_accept;
        bool bpf_xdpoffload_accept;

        bool bpf_map_accept;
        struct nsim_ipsec ipsec;
};

struct netdevsim *
nsim_create(struct nsim_dev *nsim_dev, struct nsim_dev_port *nsim_dev_port);
void nsim_destroy(struct netdevsim *ns);

#ifdef CONFIG_BPF_SYSCALL
int nsim_bpf_dev_init(struct nsim_dev *nsim_dev);
void nsim_bpf_dev_exit(struct nsim_dev *nsim_dev);
int nsim_bpf_init(struct netdevsim *ns);
void nsim_bpf_uninit(struct netdevsim *ns);
int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf);
int nsim_bpf_disable_tc(struct netdevsim *ns);
int nsim_bpf_setup_tc_block_cb(enum tc_setup_type type,
                               void *type_data, void *cb_priv);
#else

static inline int nsim_bpf_dev_init(struct nsim_dev *nsim_dev)
{
        return 0;
}

static inline void nsim_bpf_dev_exit(struct nsim_dev *nsim_dev)
{
}
static inline int nsim_bpf_init(struct netdevsim *ns)
{
        return 0;
}

static inline void nsim_bpf_uninit(struct netdevsim *ns)
{
}

static inline int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf)
{
        return bpf->command == XDP_QUERY_PROG ? 0 : -EOPNOTSUPP;
}

static inline int nsim_bpf_disable_tc(struct netdevsim *ns)
{
        return 0;
}

static inline int
nsim_bpf_setup_tc_block_cb(enum tc_setup_type type, void *type_data,
                           void *cb_priv)
{
        return -EOPNOTSUPP;
}
#endif

enum nsim_resource_id {
        NSIM_RESOURCE_NONE,   /* DEVLINK_RESOURCE_ID_PARENT_TOP */
        NSIM_RESOURCE_IPV4,
        NSIM_RESOURCE_IPV4_FIB,
        NSIM_RESOURCE_IPV4_FIB_RULES,
        NSIM_RESOURCE_IPV6,
        NSIM_RESOURCE_IPV6_FIB,
        NSIM_RESOURCE_IPV6_FIB_RULES,
};

struct nsim_dev_health {
        struct devlink_health_reporter *empty_reporter;
        struct devlink_health_reporter *dummy_reporter;
        struct dentry *ddir;
        char *recovered_break_msg;
        u32 binary_len;
        bool fail_recover;
};

int nsim_dev_health_init(struct nsim_dev *nsim_dev, struct devlink *devlink);
void nsim_dev_health_exit(struct nsim_dev *nsim_dev);

struct nsim_dev_port {
        struct list_head list;
        struct devlink_port devlink_port;
        unsigned int port_index;
        struct dentry *ddir;
        struct netdevsim *ns;
};

struct nsim_dev {
        struct nsim_bus_dev *nsim_bus_dev;
        struct nsim_fib_data *fib_data;
        struct nsim_trap_data *trap_data;
        struct dentry *ddir;
        struct dentry *ports_ddir;
        struct dentry *take_snapshot;
        struct bpf_offload_dev *bpf_dev;
        bool bpf_bind_accept;
        u32 bpf_bind_verifier_delay;
        struct dentry *ddir_bpf_bound_progs;
        u32 prog_id_gen;
        struct list_head bpf_bound_progs;
        struct list_head bpf_bound_maps;
        struct netdev_phys_item_id switch_id;
        struct list_head port_list;
        struct mutex port_list_lock; /* protects port list */
        bool fw_update_status;
        u32 max_macs;
        bool test1;
        bool dont_allow_reload;
        bool fail_reload;
        struct devlink_region *dummy_region;
        struct nsim_dev_health health;
        struct flow_action_cookie *fa_cookie;
        spinlock_t fa_cookie_lock; /* protects fa_cookie */
        bool fail_trap_group_set;
        bool fail_trap_policer_set;
        bool fail_trap_policer_counter_get;
};

static inline struct net *nsim_dev_net(struct nsim_dev *nsim_dev)
{
        return devlink_net(priv_to_devlink(nsim_dev));
}

int nsim_dev_init(void);
void nsim_dev_exit(void);
int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev);
void nsim_dev_remove(struct nsim_bus_dev *nsim_bus_dev);
int nsim_dev_port_add(struct nsim_bus_dev *nsim_bus_dev,
                      unsigned int port_index);
int nsim_dev_port_del(struct nsim_bus_dev *nsim_bus_dev,
                      unsigned int port_index);

struct nsim_fib_data *nsim_fib_create(struct devlink *devlink,
                                      struct netlink_ext_ack *extack);
void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *fib_data);
u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
                     enum nsim_resource_id res_id, bool max);

#if IS_ENABLED(CONFIG_XFRM_OFFLOAD)
void nsim_ipsec_init(struct netdevsim *ns);
void nsim_ipsec_teardown(struct netdevsim *ns);
bool nsim_ipsec_tx(struct netdevsim *ns, struct sk_buff *skb);
#else
static inline void nsim_ipsec_init(struct netdevsim *ns)
{
}

static inline void nsim_ipsec_teardown(struct netdevsim *ns)
{
}

static inline bool nsim_ipsec_tx(struct netdevsim *ns, struct sk_buff *skb)
{
        return true;
}
#endif

struct nsim_vf_config {
        int link_state;
        u16 min_tx_rate;
        u16 max_tx_rate;
        u16 vlan;
        __be16 vlan_proto;
        u16 qos;
        u8 vf_mac[ETH_ALEN];
        bool spoofchk_enabled;
        bool trusted;
        bool rss_query_enabled;
};

struct nsim_bus_dev {
        struct device dev;
        struct list_head list;
        unsigned int port_count;
        struct net *initial_net; /* Purpose of this is to carry net pointer
                                  * during the probe time only.
                                  */
        unsigned int num_vfs;
        struct nsim_vf_config *vfconfigs;
        /* Lock for devlink->reload_enabled in netdevsim module */
        struct mutex nsim_bus_reload_lock;
        bool init;
};

int nsim_bus_init(void);
void nsim_bus_exit(void);