/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * RDMA Transport Layer
 *
 * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
 * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
 * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
 */

#ifndef RTRS_SRV_H
#define RTRS_SRV_H

#include <linux/device.h>
#include <linux/refcount.h>
#include <linux/percpu.h>
#include "rtrs-pri.h"

/*
 * enum rtrs_srv_state - Server states.
 */
enum rtrs_srv_state {
        RTRS_SRV_CONNECTING,
        RTRS_SRV_CONNECTED,
        RTRS_SRV_CLOSING,
        RTRS_SRV_CLOSED,
};

/* stats for Read and write operation.
 * see Documentation/ABI/testing/sysfs-class-rtrs-server for details
 */
struct rtrs_srv_stats_rdma_stats {
        struct {
                u64 cnt;
                u64 size_total;
        } dir[2];
};

struct rtrs_srv_stats {
        struct kobject                                  kobj_stats;
        struct rtrs_srv_stats_rdma_stats __percpu       *rdma_stats;
        struct rtrs_srv_path                            *srv_path;
};

struct rtrs_srv_con {
        struct rtrs_con         c;
        struct list_head        rsp_wr_wait_list;
        spinlock_t              rsp_wr_wait_lock;
};

/* IO context in rtrs_srv, each io has one */
struct rtrs_srv_op {
        struct rtrs_srv_con             *con;
        u32                             msg_id;
        u8                              dir;
        struct rtrs_msg_rdma_read       *rd_msg;
        struct ib_rdma_wr               tx_wr;
        struct ib_sge                   tx_sg;
        struct list_head                wait_list;
        int                             status;
};

/*
 * server side memory region context, when always_invalidate=Y, we need
 * queue_depth of memory region to invalidate each memory region.
 */
struct rtrs_srv_mr {
        struct ib_mr    *mr;
        struct sg_table sgt;
        struct ib_cqe   inv_cqe;        /* only for always_invalidate=true */
        u32             msg_id;         /* only for always_invalidate=true */
        u32             msg_off;        /* only for always_invalidate=true */
        struct rtrs_iu  *iu;            /* send buffer for new rkey msg */
};

struct rtrs_srv_path {
        struct rtrs_path        s;
        struct rtrs_srv_sess    *srv;
        struct work_struct      close_work;
        enum rtrs_srv_state     state;
        spinlock_t              state_lock;
        int                     cur_cq_vector;
        struct rtrs_srv_op      **ops_ids;
        struct percpu_ref       ids_inflight_ref;
        struct completion       complete_done;
        struct rtrs_srv_mr      *mrs;
        unsigned int            mrs_num;
        dma_addr_t              *dma_addr;
        bool                    established;
        unsigned int            mem_bits;
        struct kobject          kobj;
        struct rtrs_srv_stats   *stats;
        unsigned long           connection_timeout;
};

static inline struct rtrs_srv_path *to_srv_path(struct rtrs_path *s)
{
        return container_of(s, struct rtrs_srv_path, s);
}

struct rtrs_srv_sess {
        struct list_head        paths_list;
        int                     paths_up;
        struct mutex            paths_ev_mutex;
        size_t                  paths_num;
        struct mutex            paths_mutex;
        uuid_t                  paths_uuid;
        refcount_t              refcount;
        struct rtrs_srv_ctx     *ctx;
        struct list_head        ctx_list;
        void                    *priv;
        size_t                  queue_depth;
        struct page             **chunks;
        struct device           dev;
        unsigned int            dev_ref;
        struct kobject          *kobj_paths;
};

struct rtrs_srv_ctx {
        struct rtrs_srv_ops ops;
        struct rdma_cm_id *cm_id_ip;
        struct rdma_cm_id *cm_id_ib;
        struct mutex srv_mutex;
        struct list_head srv_list;
};

struct rtrs_srv_ib_ctx {
        struct rtrs_srv_ctx     *srv_ctx;
        u16                     port;
        struct mutex            ib_dev_mutex;
        int                     ib_dev_count;
};

extern const struct class rtrs_dev_class;

void close_path(struct rtrs_srv_path *srv_path);
void rtrs_srv_ib_event_handler(struct ib_event_handler *handler,
                               struct ib_event *ibevent);

static inline void rtrs_srv_update_rdma_stats(struct rtrs_srv_stats *s,
                                              size_t size, int d)
{
        this_cpu_inc(s->rdma_stats->dir[d].cnt);
        this_cpu_add(s->rdma_stats->dir[d].size_total, size);
}

/* functions which are implemented in rtrs-srv-stats.c */
int rtrs_srv_reset_rdma_stats(struct rtrs_srv_stats *stats, bool enable);
ssize_t rtrs_srv_stats_rdma_to_str(struct rtrs_srv_stats *stats, char *page);
int rtrs_srv_reset_all_stats(struct rtrs_srv_stats *stats, bool enable);
ssize_t rtrs_srv_reset_all_help(struct rtrs_srv_stats *stats,
                                 char *page, size_t len);

/* functions which are implemented in rtrs-srv-sysfs.c */
int rtrs_srv_create_path_files(struct rtrs_srv_path *srv_path);
void rtrs_srv_destroy_path_files(struct rtrs_srv_path *srv_path);

#endif /* RTRS_SRV_H */