/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
/*
 * Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
 */

#ifndef _RDMA_RESTRACK_H_
#define _RDMA_RESTRACK_H_

#include <linux/typecheck.h>
#include <linux/sched.h>
#include <linux/kref.h>
#include <linux/completion.h>
#include <linux/sched/task.h>
#include <uapi/rdma/rdma_netlink.h>
#include <linux/xarray.h>

/* Mark entry as containing driver specific details, it is used to provide QP subtype for now */
#define RESTRACK_DD XA_MARK_1

struct ib_device;
struct sk_buff;

/**
 * enum rdma_restrack_type - HW objects to track
 */
enum rdma_restrack_type {
        /**
         * @RDMA_RESTRACK_PD: Protection domain (PD)
         */
        RDMA_RESTRACK_PD,
        /**
         * @RDMA_RESTRACK_CQ: Completion queue (CQ)
         */
        RDMA_RESTRACK_CQ,
        /**
         * @RDMA_RESTRACK_QP: Queue pair (QP)
         */
        RDMA_RESTRACK_QP,
        /**
         * @RDMA_RESTRACK_CM_ID: Connection Manager ID (CM_ID)
         */
        RDMA_RESTRACK_CM_ID,
        /**
         * @RDMA_RESTRACK_MR: Memory Region (MR)
         */
        RDMA_RESTRACK_MR,
        /**
         * @RDMA_RESTRACK_CTX: Verbs contexts (CTX)
         */
        RDMA_RESTRACK_CTX,
        /**
         * @RDMA_RESTRACK_COUNTER: Statistic Counter
         */
        RDMA_RESTRACK_COUNTER,
        /**
         * @RDMA_RESTRACK_SRQ: Shared receive queue (SRQ)
         */
        RDMA_RESTRACK_SRQ,
        /**
         * @RDMA_RESTRACK_DMAH: DMA handle
         */
        RDMA_RESTRACK_DMAH,
        /**
         * @RDMA_RESTRACK_MAX: Last entry, used for array dclarations
         */
        RDMA_RESTRACK_MAX
};

/**
 * struct rdma_restrack_entry - metadata per-entry
 */
struct rdma_restrack_entry {
        /**
         * @valid: validity indicator
         *
         * The entries are filled during rdma_restrack_add,
         * can be attempted to be free during rdma_restrack_del.
         *
         * As an example for that, see mlx5 QPs with type MLX5_IB_QPT_HW_GSI
         */
        bool                    valid;
        /**
         * @no_track: don't add this entry to restrack DB
         *
         * This field is used to mark an entry that doesn't need to be added to
         * internal restrack DB and presented later to the users at the nldev
         * query stage.
         */
        u8                      no_track : 1;
        /*
         * @kref: Protect destroy of the resource
         */
        struct kref             kref;
        /*
         * @comp: Signal that all consumers of resource are completed their work
         */
        struct completion       comp;
        /**
         * @task: owner of resource tracking entity
         *
         * There are two types of entities: created by user and created
         * by kernel.
         *
         * This is relevant for the entities created by users.
         * For the entities created by kernel, this pointer will be NULL.
         */
        struct task_struct      *task;
        /**
         * @kern_name: name of owner for the kernel created entities.
         */
        const char              *kern_name;
        /**
         * @type: various objects in restrack database
         */
        enum rdma_restrack_type type;
        /**
         * @user: user resource
         */
        bool                    user;
        /**
         * @id: ID to expose to users
         */
        u32 id;
};

int rdma_restrack_count(struct ib_device *dev, enum rdma_restrack_type type,
                        bool show_details);
/**
 * rdma_is_kernel_res() - check the owner of resource
 * @res:  resource entry
 */
static inline bool rdma_is_kernel_res(const struct rdma_restrack_entry *res)
{
        return !res->user;
}

/**
 * rdma_restrack_get() - grab to protect resource from release
 * @res:  resource entry
 */
int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);

/**
 * rdma_restrack_put() - release resource
 * @res:  resource entry
 */
int rdma_restrack_put(struct rdma_restrack_entry *res);

/*
 * Helper functions for rdma drivers when filling out
 * nldev driver attributes.
 */
int rdma_nl_put_driver_u32(struct sk_buff *msg, const char *name, u32 value);
int rdma_nl_put_driver_u32_hex(struct sk_buff *msg, const char *name,
                               u32 value);
int rdma_nl_put_driver_u64(struct sk_buff *msg, const char *name, u64 value);
int rdma_nl_put_driver_u64_hex(struct sk_buff *msg, const char *name,
                               u64 value);
int rdma_nl_put_driver_string(struct sk_buff *msg, const char *name,
                              const char *str);
int rdma_nl_stat_hwcounter_entry(struct sk_buff *msg, const char *name,
                                 u64 value);

struct rdma_restrack_entry *rdma_restrack_get_byid(struct ib_device *dev,
                                                   enum rdma_restrack_type type,
                                                   u32 id);

/**
 * rdma_restrack_no_track() - don't add resource to the DB
 * @res: resource entry
 *
 * Every user of this API should be cross examined.
 * Probably you don't need to use this function.
 */
static inline void rdma_restrack_no_track(struct rdma_restrack_entry *res)
{
        res->no_track = true;
}
static inline bool rdma_restrack_is_tracked(struct rdma_restrack_entry *res)
{
        return !res->no_track;
}
#endif /* _RDMA_RESTRACK_H_ */