/*-
 * Copyright (c) 2013-2017, Mellanox Technologies, Ltd.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS `AS IS' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "opt_rss.h"
#include "opt_ratelimit.h"

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/hardirq.h>
#include <dev/mlx5/driver.h>
#include <rdma/ib_verbs.h>
#include <dev/mlx5/cq.h>
#include <dev/mlx5/mlx5_core/mlx5_core.h>

#include <sys/epoch.h>

static void
mlx5_cq_table_write_lock(struct mlx5_cq_table *table)
{

        atomic_inc(&table->writercount);
        /* make sure all see the updated writercount */
        NET_EPOCH_WAIT();
        spin_lock(&table->writerlock);
}

static void
mlx5_cq_table_write_unlock(struct mlx5_cq_table *table)
{

        spin_unlock(&table->writerlock);
        atomic_dec(&table->writercount);
        /* drain all pending CQ callers */
        NET_EPOCH_WAIT();
}

void mlx5_cq_completion(struct mlx5_core_dev *dev, struct mlx5_eqe *eqe)
{
        struct mlx5_cq_table *table = &dev->priv.cq_table;
        struct mlx5_core_cq *cq;
        struct epoch_tracker et;
        u32 cqn;
        bool do_lock;

        cqn = be32_to_cpu(eqe->data.comp.cqn) & 0xffffff;

        NET_EPOCH_ENTER(et);

        do_lock = atomic_read(&table->writercount) != 0;
        if (unlikely(do_lock))
                spin_lock(&table->writerlock);

        if (likely(cqn < MLX5_CQ_LINEAR_ARRAY_SIZE))
                cq = table->linear_array[cqn].cq;
        else
                cq = radix_tree_lookup(&table->tree, cqn);

        if (unlikely(do_lock))
                spin_unlock(&table->writerlock);

        if (likely(cq != NULL)) {
                ++cq->arm_sn;
                cq->comp(cq, eqe);
        } else {
                mlx5_core_warn(dev,
                    "Completion event for bogus CQ 0x%x\n", cqn);
        }

        NET_EPOCH_EXIT(et);
}

void mlx5_cq_event(struct mlx5_core_dev *dev, u32 cqn, int event_type)
{
        struct mlx5_cq_table *table = &dev->priv.cq_table;
        struct mlx5_core_cq *cq;
        struct epoch_tracker et;
        bool do_lock;

        NET_EPOCH_ENTER(et);

        do_lock = atomic_read(&table->writercount) != 0;
        if (unlikely(do_lock))
                spin_lock(&table->writerlock);

        if (likely(cqn < MLX5_CQ_LINEAR_ARRAY_SIZE))
                cq = table->linear_array[cqn].cq;
        else
                cq = radix_tree_lookup(&table->tree, cqn);

        if (unlikely(do_lock))
                spin_unlock(&table->writerlock);

        if (likely(cq != NULL)) {
                cq->event(cq, event_type);
        } else {
                mlx5_core_warn(dev,
                    "Asynchronous event for bogus CQ 0x%x\n", cqn);
        }

        NET_EPOCH_EXIT(et);
}

int mlx5_core_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
                        u32 *in, int inlen, u32 *out, int outlen)
{
        struct mlx5_cq_table *table = &dev->priv.cq_table;
        u32 din[MLX5_ST_SZ_DW(destroy_cq_in)] = {0};
        u32 dout[MLX5_ST_SZ_DW(destroy_cq_out)] = {0};
        int err;

        memset(out, 0, outlen);
        MLX5_SET(create_cq_in, in, opcode, MLX5_CMD_OP_CREATE_CQ);
        err = mlx5_cmd_exec(dev, in, inlen, out, outlen);
        if (err)
                return err;

        cq->cqn = MLX5_GET(create_cq_out, out, cqn);
        cq->cons_index = 0;
        cq->arm_sn     = 0;

        mlx5_cq_table_write_lock(table);
        err = radix_tree_insert(&table->tree, cq->cqn, cq);
        if (likely(err == 0 && cq->cqn < MLX5_CQ_LINEAR_ARRAY_SIZE))
                table->linear_array[cq->cqn].cq = cq;
        mlx5_cq_table_write_unlock(table);

        if (err)
                goto err_cmd;

        cq->pid = curthread->td_proc->p_pid;
        cq->uar = dev->priv.uar;

        return 0;

err_cmd:
        MLX5_SET(destroy_cq_in, din, opcode, MLX5_CMD_OP_DESTROY_CQ);
        MLX5_SET(destroy_cq_in, din, cqn, cq->cqn);
        mlx5_cmd_exec(dev, din, sizeof(din), dout, sizeof(dout));
        return err;
}
EXPORT_SYMBOL(mlx5_core_create_cq);

int mlx5_core_destroy_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq)
{
        struct mlx5_cq_table *table = &dev->priv.cq_table;
        u32 out[MLX5_ST_SZ_DW(destroy_cq_out)] = {0};
        u32 in[MLX5_ST_SZ_DW(destroy_cq_in)] = {0};
        struct mlx5_core_cq *tmp;

        mlx5_cq_table_write_lock(table);
        if (likely(cq->cqn < MLX5_CQ_LINEAR_ARRAY_SIZE))
                table->linear_array[cq->cqn].cq = NULL;
        tmp = radix_tree_delete(&table->tree, cq->cqn);
        mlx5_cq_table_write_unlock(table);

        if (unlikely(tmp == NULL)) {
                mlx5_core_warn(dev, "cq 0x%x not found in tree\n", cq->cqn);
                return -EINVAL;
        } else if (unlikely(tmp != cq)) {
                mlx5_core_warn(dev, "corrupted cqn 0x%x\n", cq->cqn);
                return -EINVAL;
        }

        MLX5_SET(destroy_cq_in, in, opcode, MLX5_CMD_OP_DESTROY_CQ);
        MLX5_SET(destroy_cq_in, in, cqn, cq->cqn);
        return mlx5_cmd_exec(dev, in, sizeof(in), out, sizeof(out));
}
EXPORT_SYMBOL(mlx5_core_destroy_cq);

int mlx5_core_query_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
                       u32 *out, int outlen)
{
        u32 in[MLX5_ST_SZ_DW(query_cq_in)] = {0};

        MLX5_SET(query_cq_in, in, opcode, MLX5_CMD_OP_QUERY_CQ);
        MLX5_SET(query_cq_in, in, cqn, cq->cqn);

        return mlx5_cmd_exec(dev, in, sizeof(in), out, outlen);
}
EXPORT_SYMBOL(mlx5_core_query_cq);


int mlx5_core_modify_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
                        u32 *in, int inlen)
{
        u32 out[MLX5_ST_SZ_DW(modify_cq_out)] = {0};

        MLX5_SET(modify_cq_in, in, opcode, MLX5_CMD_OP_MODIFY_CQ);
        return mlx5_cmd_exec(dev, in, inlen, out, sizeof(out));
}
EXPORT_SYMBOL(mlx5_core_modify_cq);

int mlx5_core_modify_cq_moderation(struct mlx5_core_dev *dev,
                                   struct mlx5_core_cq *cq,
                                   u16 cq_period,
                                   u16 cq_max_count)
{
        return (mlx5_core_modify_cq_by_mask(dev, cq,
            MLX5_CQ_MODIFY_PERIOD | MLX5_CQ_MODIFY_COUNT,
            cq_period, cq_max_count, 0, 0));
}

int mlx5_core_modify_cq_moderation_mode(struct mlx5_core_dev *dev,
                                        struct mlx5_core_cq *cq,
                                        u16 cq_period,
                                        u16 cq_max_count,
                                        u8 cq_mode)
{
        return (mlx5_core_modify_cq_by_mask(dev, cq,
            MLX5_CQ_MODIFY_PERIOD | MLX5_CQ_MODIFY_COUNT | MLX5_CQ_MODIFY_PERIOD_MODE,
            cq_period, cq_max_count, cq_mode, 0));
}

int
mlx5_core_modify_cq_by_mask(struct mlx5_core_dev *dev,
    struct mlx5_core_cq *cq, u32 mask,
    u16 cq_period, u16 cq_max_count, u8 cq_mode, u8 cq_eqn)
{
        u32 in[MLX5_ST_SZ_DW(modify_cq_in)] = {};
        void *cqc;

        MLX5_SET(modify_cq_in, in, cqn, cq->cqn);
        cqc = MLX5_ADDR_OF(modify_cq_in, in, cq_context);
        if (mask & MLX5_CQ_MODIFY_PERIOD)
                MLX5_SET(cqc, cqc, cq_period, cq_period);
        if (mask & MLX5_CQ_MODIFY_COUNT)
                MLX5_SET(cqc, cqc, cq_max_count, cq_max_count);
        if (mask & MLX5_CQ_MODIFY_PERIOD_MODE)
                MLX5_SET(cqc, cqc, cq_period_mode, cq_mode);
        if (mask & MLX5_CQ_MODIFY_EQN)
                MLX5_SET(cqc, cqc, c_eqn, cq_eqn);

        MLX5_SET(modify_cq_in, in,
            modify_field_select_resize_field_select.modify_field_select.modify_field_select, mask);

        return (mlx5_core_modify_cq(dev, cq, in, sizeof(in)));
}

int mlx5_init_cq_table(struct mlx5_core_dev *dev)
{
        struct mlx5_cq_table *table = &dev->priv.cq_table;

        memset(table, 0, sizeof(*table));
        spin_lock_init(&table->writerlock);
        INIT_RADIX_TREE(&table->tree, GFP_ATOMIC);

        return 0;
}

void mlx5_cleanup_cq_table(struct mlx5_core_dev *dev)
{
}