/*
 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
 * Copyright (c) 2015 System Fabric Works, Inc. 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 "rxe.h"
#include "rxe_loc.h"

int rxe_mcast_get_grp(struct rxe_dev *rxe, union ib_gid *mgid,
                      struct rxe_mc_grp **grp_p)
{
        int err;
        struct rxe_mc_grp *grp;

        if (rxe->attr.max_mcast_qp_attach == 0) {
                err = -EINVAL;
                goto err1;
        }

        grp = rxe_pool_get_key(&rxe->mc_grp_pool, mgid);
        if (grp)
                goto done;

        grp = rxe_alloc(&rxe->mc_grp_pool);
        if (!grp) {
                err = -ENOMEM;
                goto err1;
        }

        INIT_LIST_HEAD(&grp->qp_list);
        spin_lock_init(&grp->mcg_lock);
        grp->rxe = rxe;

        rxe_add_key(grp, mgid);

        err = rxe_mcast_add(rxe, mgid);
        if (err)
                goto err2;

done:
        *grp_p = grp;
        return 0;

err2:
        rxe_drop_ref(grp);
err1:
        return err;
}

int rxe_mcast_add_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
                           struct rxe_mc_grp *grp)
{
        int err;
        struct rxe_mc_elem *elem;

        /* check to see of the qp is already a member of the group */
        spin_lock_bh(&qp->grp_lock);
        spin_lock_bh(&grp->mcg_lock);
        list_for_each_entry(elem, &grp->qp_list, qp_list) {
                if (elem->qp == qp) {
                        err = 0;
                        goto out;
                }
        }

        if (grp->num_qp >= rxe->attr.max_mcast_qp_attach) {
                err = -ENOMEM;
                goto out;
        }

        elem = rxe_alloc(&rxe->mc_elem_pool);
        if (!elem) {
                err = -ENOMEM;
                goto out;
        }

        /* each qp holds a ref on the grp */
        rxe_add_ref(grp);

        grp->num_qp++;
        elem->qp = qp;
        elem->grp = grp;

        list_add(&elem->qp_list, &grp->qp_list);
        list_add(&elem->grp_list, &qp->grp_list);

        err = 0;
out:
        spin_unlock_bh(&grp->mcg_lock);
        spin_unlock_bh(&qp->grp_lock);
        return err;
}

int rxe_mcast_drop_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
                            union ib_gid *mgid)
{
        struct rxe_mc_grp *grp;
        struct rxe_mc_elem *elem, *tmp;

        grp = rxe_pool_get_key(&rxe->mc_grp_pool, mgid);
        if (!grp)
                goto err1;

        spin_lock_bh(&qp->grp_lock);
        spin_lock_bh(&grp->mcg_lock);

        list_for_each_entry_safe(elem, tmp, &grp->qp_list, qp_list) {
                if (elem->qp == qp) {
                        list_del(&elem->qp_list);
                        list_del(&elem->grp_list);
                        grp->num_qp--;

                        spin_unlock_bh(&grp->mcg_lock);
                        spin_unlock_bh(&qp->grp_lock);
                        rxe_drop_ref(elem);
                        rxe_drop_ref(grp);      /* ref held by QP */
                        rxe_drop_ref(grp);      /* ref from get_key */
                        return 0;
                }
        }

        spin_unlock_bh(&grp->mcg_lock);
        spin_unlock_bh(&qp->grp_lock);
        rxe_drop_ref(grp);                      /* ref from get_key */
err1:
        return -EINVAL;
}

void rxe_drop_all_mcast_groups(struct rxe_qp *qp)
{
        struct rxe_mc_grp *grp;
        struct rxe_mc_elem *elem;

        while (1) {
                spin_lock_bh(&qp->grp_lock);
                if (list_empty(&qp->grp_list)) {
                        spin_unlock_bh(&qp->grp_lock);
                        break;
                }
                elem = list_first_entry(&qp->grp_list, struct rxe_mc_elem,
                                        grp_list);
                list_del(&elem->grp_list);
                spin_unlock_bh(&qp->grp_lock);

                grp = elem->grp;
                spin_lock_bh(&grp->mcg_lock);
                list_del(&elem->qp_list);
                grp->num_qp--;
                spin_unlock_bh(&grp->mcg_lock);
                rxe_drop_ref(grp);
                rxe_drop_ref(elem);
        }
}

void rxe_mc_cleanup(struct rxe_pool_entry *arg)
{
        struct rxe_mc_grp *grp = container_of(arg, typeof(*grp), pelem);
        struct rxe_dev *rxe = grp->rxe;

        rxe_drop_key(grp);
        rxe_mcast_delete(rxe, &grp->mgid);
}