/*
 * Copyright (c) 2017, Mellanox Technologies. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - 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.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/hash.h>
#include "ipoib.h"

#define MLX5I_MAX_LOG_PKEY_SUP 7

struct qpn_to_netdev {
        struct net_device *netdev;
        struct hlist_node hlist;
        u32 underlay_qpn;
};

struct mlx5i_pkey_qpn_ht {
        struct hlist_head buckets[1 << MLX5I_MAX_LOG_PKEY_SUP];
        spinlock_t ht_lock; /* Synchronise with NAPI */
};

int mlx5i_pkey_qpn_ht_init(struct net_device *netdev)
{
        struct mlx5i_priv *ipriv = netdev_priv(netdev);
        struct mlx5i_pkey_qpn_ht *qpn_htbl;

        qpn_htbl = kzalloc_obj(*qpn_htbl);
        if (!qpn_htbl)
                return -ENOMEM;

        ipriv->qpn_htbl = qpn_htbl;
        spin_lock_init(&qpn_htbl->ht_lock);

        return 0;
}

void mlx5i_pkey_qpn_ht_cleanup(struct net_device *netdev)
{
        struct mlx5i_priv *ipriv = netdev_priv(netdev);

        kfree(ipriv->qpn_htbl);
}

static struct qpn_to_netdev *mlx5i_find_qpn_to_netdev_node(struct hlist_head *buckets,
                                                           u32 qpn)
{
        struct hlist_head *h = &buckets[hash_32(qpn, MLX5I_MAX_LOG_PKEY_SUP)];
        struct qpn_to_netdev *node;

        hlist_for_each_entry(node, h, hlist) {
                if (node->underlay_qpn == qpn)
                        return node;
        }

        return NULL;
}

int mlx5i_pkey_add_qpn(struct net_device *netdev, u32 qpn)
{
        struct mlx5i_priv *ipriv = netdev_priv(netdev);
        struct mlx5i_pkey_qpn_ht *ht = ipriv->qpn_htbl;
        u8 key = hash_32(qpn, MLX5I_MAX_LOG_PKEY_SUP);
        struct qpn_to_netdev *new_node;

        new_node = kzalloc_obj(*new_node);
        if (!new_node)
                return -ENOMEM;

        new_node->netdev = netdev;
        new_node->underlay_qpn = qpn;
        spin_lock_bh(&ht->ht_lock);
        hlist_add_head(&new_node->hlist, &ht->buckets[key]);
        spin_unlock_bh(&ht->ht_lock);

        return 0;
}

int mlx5i_pkey_del_qpn(struct net_device *netdev, u32 qpn)
{
        struct mlx5e_priv *epriv = mlx5i_epriv(netdev);
        struct mlx5i_priv *ipriv = epriv->ppriv;
        struct mlx5i_pkey_qpn_ht *ht = ipriv->qpn_htbl;
        struct qpn_to_netdev *node;

        node = mlx5i_find_qpn_to_netdev_node(ht->buckets, qpn);
        if (!node) {
                mlx5_core_warn(epriv->mdev, "QPN to netdev delete from HT failed\n");
                return -EINVAL;
        }

        spin_lock_bh(&ht->ht_lock);
        hlist_del_init(&node->hlist);
        spin_unlock_bh(&ht->ht_lock);
        kfree(node);

        return 0;
}

struct net_device *mlx5i_pkey_get_netdev(struct net_device *netdev, u32 qpn)
{
        struct mlx5i_priv *ipriv = netdev_priv(netdev);
        struct qpn_to_netdev *node;

        node = mlx5i_find_qpn_to_netdev_node(ipriv->qpn_htbl->buckets, qpn);
        if (!node)
                return NULL;

        return node->netdev;
}

static int mlx5i_pkey_open(struct net_device *netdev);
static int mlx5i_pkey_close(struct net_device *netdev);
static int mlx5i_pkey_dev_init(struct net_device *dev);
static void mlx5i_pkey_dev_cleanup(struct net_device *netdev);
static int mlx5i_pkey_change_mtu(struct net_device *netdev, int new_mtu);

static const struct net_device_ops mlx5i_pkey_netdev_ops = {
        .ndo_open                = mlx5i_pkey_open,
        .ndo_stop                = mlx5i_pkey_close,
        .ndo_init                = mlx5i_pkey_dev_init,
        .ndo_get_stats64         = mlx5i_get_stats,
        .ndo_uninit              = mlx5i_pkey_dev_cleanup,
        .ndo_change_mtu          = mlx5i_pkey_change_mtu,
        .ndo_hwtstamp_get        = mlx5i_hwtstamp_get,
        .ndo_hwtstamp_set        = mlx5i_hwtstamp_set,
};

/* Child NDOs */
static int mlx5i_pkey_dev_init(struct net_device *dev)
{
        struct mlx5e_priv *priv = mlx5i_epriv(dev);
        struct mlx5i_priv *ipriv, *parent_ipriv;
        struct net_device *parent_dev;

        ipriv = priv->ppriv;

        /* Link to parent */
        parent_dev = mlx5i_parent_get(dev);
        if (!parent_dev) {
                mlx5_core_warn(priv->mdev, "failed to get parent device\n");
                return -EINVAL;
        }

        if (dev->num_rx_queues < parent_dev->real_num_rx_queues) {
                mlx5_core_warn(priv->mdev,
                               "failed to create child device with rx queues [%d] less than parent's [%d]\n",
                               dev->num_rx_queues,
                               parent_dev->real_num_rx_queues);
                mlx5i_parent_put(dev);
                return -EINVAL;
        }

        /* Get QPN to netdevice hash table from parent */
        parent_ipriv = netdev_priv(parent_dev);
        ipriv->qpn_htbl = parent_ipriv->qpn_htbl;

        return mlx5i_dev_init(dev);
}

static void mlx5i_pkey_dev_cleanup(struct net_device *netdev)
{
        mlx5i_parent_put(netdev);
        return mlx5i_dev_cleanup(netdev);
}

static int mlx5i_pkey_open(struct net_device *netdev)
{
        struct mlx5e_priv *epriv = mlx5i_epriv(netdev);
        struct mlx5i_priv *ipriv = epriv->ppriv;
        struct mlx5_core_dev *mdev = epriv->mdev;
        int err;

        mutex_lock(&epriv->state_lock);

        set_bit(MLX5E_STATE_OPENED, &epriv->state);

        err = mlx5i_init_underlay_qp(epriv);
        if (err) {
                mlx5_core_warn(mdev, "prepare child underlay qp state failed, %d\n", err);
                goto err_release_lock;
        }

        err = mlx5_fs_add_rx_underlay_qpn(mdev, ipriv->qpn);
        if (err) {
                mlx5_core_warn(mdev, "attach child underlay qp to ft failed, %d\n", err);
                goto err_unint_underlay_qp;
        }

        err = mlx5i_create_tis(mdev, ipriv->qpn, &ipriv->tisn);
        if (err) {
                mlx5_core_warn(mdev, "create child tis failed, %d\n", err);
                goto err_remove_rx_uderlay_qp;
        }

        err = mlx5e_open_channels(epriv, &epriv->channels);
        if (err) {
                mlx5_core_warn(mdev, "opening child channels failed, %d\n", err);
                goto err_clear_state_opened_flag;
        }
        err = epriv->profile->update_rx(epriv);
        if (err)
                goto err_close_channels;
        mlx5e_activate_priv_channels(epriv);
        mutex_unlock(&epriv->state_lock);

        return 0;

err_close_channels:
        mlx5e_close_channels(&epriv->channels);
err_clear_state_opened_flag:
        mlx5e_destroy_tis(mdev, ipriv->tisn);
err_remove_rx_uderlay_qp:
        mlx5_fs_remove_rx_underlay_qpn(mdev, ipriv->qpn);
err_unint_underlay_qp:
        mlx5i_uninit_underlay_qp(epriv);
err_release_lock:
        clear_bit(MLX5E_STATE_OPENED, &epriv->state);
        mutex_unlock(&epriv->state_lock);
        return err;
}

static int mlx5i_pkey_close(struct net_device *netdev)
{
        struct mlx5e_priv *priv = mlx5i_epriv(netdev);
        struct mlx5i_priv *ipriv = priv->ppriv;
        struct mlx5_core_dev *mdev = priv->mdev;

        mutex_lock(&priv->state_lock);

        if (!test_bit(MLX5E_STATE_OPENED, &priv->state))
                goto unlock;

        clear_bit(MLX5E_STATE_OPENED, &priv->state);

        netif_carrier_off(priv->netdev);
        mlx5_fs_remove_rx_underlay_qpn(mdev, ipriv->qpn);
        mlx5i_uninit_underlay_qp(priv);
        mlx5e_deactivate_priv_channels(priv);
        mlx5e_close_channels(&priv->channels);
        mlx5e_destroy_tis(mdev, ipriv->tisn);
unlock:
        mutex_unlock(&priv->state_lock);
        return 0;
}

static int mlx5i_pkey_change_mtu(struct net_device *netdev, int new_mtu)
{
        struct mlx5e_priv *priv = mlx5i_epriv(netdev);

        mutex_lock(&priv->state_lock);
        WRITE_ONCE(netdev->mtu, new_mtu);
        mutex_unlock(&priv->state_lock);

        return 0;
}

/* Called directly after IPoIB netdevice was created to initialize SW structs */
static int mlx5i_pkey_init(struct mlx5_core_dev *mdev,
                           struct net_device *netdev)
{
        struct mlx5e_priv *priv  = mlx5i_epriv(netdev);
        int err;

        err = mlx5i_init(mdev, netdev);
        if (err)
                return err;

        /* Override parent ndo */
        netdev->netdev_ops = &mlx5i_pkey_netdev_ops;

        /* Set child limited ethtool support */
        netdev->ethtool_ops = &mlx5i_pkey_ethtool_ops;

        /* Use dummy rqs */
        priv->channels.params.log_rq_mtu_frames = MLX5E_PARAMS_MINIMUM_LOG_RQ_SIZE;

        return 0;
}

/* Called directly before IPoIB netdevice is destroyed to cleanup SW structs */
static void mlx5i_pkey_cleanup(struct mlx5e_priv *priv)
{
        mlx5i_cleanup(priv);
}

static int mlx5i_pkey_init_tx(struct mlx5e_priv *priv)
{
        int err;

        err = mlx5i_create_underlay_qp(priv);
        if (err)
                mlx5_core_warn(priv->mdev, "create child underlay QP failed, %d\n", err);

        return err;
}

static void mlx5i_pkey_cleanup_tx(struct mlx5e_priv *priv)
{
        struct mlx5i_priv *ipriv = priv->ppriv;

        mlx5i_destroy_underlay_qp(priv->mdev, ipriv->qpn);
}

static int mlx5i_pkey_init_rx(struct mlx5e_priv *priv)
{
        /* Since the rx resources are shared between child and parent, the
         * parent interface is taking care of rx resource allocation and init
         */
        return 0;
}

static void mlx5i_pkey_cleanup_rx(struct mlx5e_priv *priv)
{
        /* Since the rx resources are shared between child and parent, the
         * parent interface is taking care of rx resource free and de-init
         */
}

static const struct mlx5e_profile mlx5i_pkey_nic_profile = {
        .init              = mlx5i_pkey_init,
        .cleanup           = mlx5i_pkey_cleanup,
        .init_tx           = mlx5i_pkey_init_tx,
        .cleanup_tx        = mlx5i_pkey_cleanup_tx,
        .init_rx           = mlx5i_pkey_init_rx,
        .cleanup_rx        = mlx5i_pkey_cleanup_rx,
        .enable            = NULL,
        .disable           = NULL,
        .update_rx         = mlx5i_update_nic_rx,
        .update_stats      = NULL,
        .rx_handlers       = &mlx5i_rx_handlers,
        .max_tc            = MLX5I_MAX_NUM_TC,
        .get_tisn          = mlx5i_get_tisn,
};

const struct mlx5e_profile *mlx5i_pkey_get_profile(void)
{
        return &mlx5i_pkey_nic_profile;
}