/*
 * 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 <linux/vmalloc.h>
#include "rxe.h"
#include "rxe_loc.h"
#include "rxe_queue.h"

int rxe_cq_chk_attr(struct rxe_dev *rxe, struct rxe_cq *cq,
                    int cqe, int comp_vector)
{
        int count;

        if (cqe <= 0) {
                pr_warn("cqe(%d) <= 0\n", cqe);
                goto err1;
        }

        if (cqe > rxe->attr.max_cqe) {
                pr_warn("cqe(%d) > max_cqe(%d)\n",
                        cqe, rxe->attr.max_cqe);
                goto err1;
        }

        if (cq) {
                count = queue_count(cq->queue);
                if (cqe < count) {
                        pr_warn("cqe(%d) < current # elements in queue (%d)",
                                cqe, count);
                        goto err1;
                }
        }

        return 0;

err1:
        return -EINVAL;
}

static void rxe_send_complete(unsigned long data)
{
        struct rxe_cq *cq = (struct rxe_cq *)data;
        unsigned long flags;

        spin_lock_irqsave(&cq->cq_lock, flags);
        if (cq->is_dying) {
                spin_unlock_irqrestore(&cq->cq_lock, flags);
                return;
        }
        spin_unlock_irqrestore(&cq->cq_lock, flags);

        cq->ibcq.comp_handler(&cq->ibcq, cq->ibcq.cq_context);
}

int rxe_cq_from_init(struct rxe_dev *rxe, struct rxe_cq *cq, int cqe,
                     int comp_vector, struct ib_ucontext *context,
                     struct rxe_create_cq_resp __user *uresp)
{
        int err;

        cq->queue = rxe_queue_init(rxe, &cqe,
                                   sizeof(struct rxe_cqe));
        if (!cq->queue) {
                pr_warn("unable to create cq\n");
                return -ENOMEM;
        }

        err = do_mmap_info(rxe, uresp ? &uresp->mi : NULL, context,
                           cq->queue->buf, cq->queue->buf_size, &cq->queue->ip);
        if (err) {
                vfree(cq->queue->buf);
                kfree(cq->queue);
                return err;
        }

        if (uresp)
                cq->is_user = 1;

        cq->is_dying = false;

        tasklet_init(&cq->comp_task, rxe_send_complete, (unsigned long)cq);

        spin_lock_init(&cq->cq_lock);
        cq->ibcq.cqe = cqe;
        return 0;
}

int rxe_cq_resize_queue(struct rxe_cq *cq, int cqe,
                        struct rxe_resize_cq_resp __user *uresp)
{
        int err;

        err = rxe_queue_resize(cq->queue, (unsigned int *)&cqe,
                               sizeof(struct rxe_cqe),
                               cq->queue->ip ? cq->queue->ip->context : NULL,
                               uresp ? &uresp->mi : NULL, NULL, &cq->cq_lock);
        if (!err)
                cq->ibcq.cqe = cqe;

        return err;
}

int rxe_cq_post(struct rxe_cq *cq, struct rxe_cqe *cqe, int solicited)
{
        struct ib_event ev;
        unsigned long flags;

        spin_lock_irqsave(&cq->cq_lock, flags);

        if (unlikely(queue_full(cq->queue))) {
                spin_unlock_irqrestore(&cq->cq_lock, flags);
                if (cq->ibcq.event_handler) {
                        ev.device = cq->ibcq.device;
                        ev.element.cq = &cq->ibcq;
                        ev.event = IB_EVENT_CQ_ERR;
                        cq->ibcq.event_handler(&ev, cq->ibcq.cq_context);
                }

                return -EBUSY;
        }

        memcpy(producer_addr(cq->queue), cqe, sizeof(*cqe));

        /* make sure all changes to the CQ are written before we update the
         * producer pointer
         */
        smp_wmb();

        advance_producer(cq->queue);
        spin_unlock_irqrestore(&cq->cq_lock, flags);

        if ((cq->notify == IB_CQ_NEXT_COMP) ||
            (cq->notify == IB_CQ_SOLICITED && solicited)) {
                cq->notify = 0;
                tasklet_schedule(&cq->comp_task);
        }

        return 0;
}

void rxe_cq_disable(struct rxe_cq *cq)
{
        unsigned long flags;

        spin_lock_irqsave(&cq->cq_lock, flags);
        cq->is_dying = true;
        spin_unlock_irqrestore(&cq->cq_lock, flags);
}

void rxe_cq_cleanup(struct rxe_pool_entry *arg)
{
        struct rxe_cq *cq = container_of(arg, typeof(*cq), pelem);

        if (cq->queue)
                rxe_queue_cleanup(cq->queue);
}