// SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
/* Copyright(c) 2022 Intel Corporation */
#include <crypto/algapi.h>
#include "adf_transport.h"
#include "qat_algs_send.h"
#include "qat_crypto.h"

#define ADF_MAX_RETRIES         20

static int qat_alg_send_message_retry(struct qat_alg_req *req)
{
        int ret = 0, ctr = 0;

        do {
                ret = adf_send_message(req->tx_ring, req->fw_req);
        } while (ret == -EAGAIN && ctr++ < ADF_MAX_RETRIES);

        if (ret == -EAGAIN)
                return -ENOSPC;

        return -EINPROGRESS;
}

void qat_alg_send_backlog(struct qat_instance_backlog *backlog)
{
        struct qat_alg_req *req, *tmp;

        spin_lock_bh(&backlog->lock);
        list_for_each_entry_safe(req, tmp, &backlog->list, list) {
                if (adf_send_message(req->tx_ring, req->fw_req)) {
                        /* The HW ring is full. Do nothing.
                         * qat_alg_send_backlog() will be invoked again by
                         * another callback.
                         */
                        break;
                }
                list_del(&req->list);
                crypto_request_complete(req->base, -EINPROGRESS);
        }
        spin_unlock_bh(&backlog->lock);
}

static bool qat_alg_try_enqueue(struct qat_alg_req *req)
{
        struct qat_instance_backlog *backlog = req->backlog;
        struct adf_etr_ring_data *tx_ring = req->tx_ring;
        u32 *fw_req = req->fw_req;

        /* Check if any request is already backlogged */
        if (!list_empty(&backlog->list))
                return false;

        /* Check if ring is nearly full */
        if (adf_ring_nearly_full(tx_ring))
                return false;

        /* Try to enqueue to HW ring */
        if (adf_send_message(tx_ring, fw_req))
                return false;

        return true;
}


static int qat_alg_send_message_maybacklog(struct qat_alg_req *req)
{
        struct qat_instance_backlog *backlog = req->backlog;
        int ret = -EINPROGRESS;

        if (qat_alg_try_enqueue(req))
                return ret;

        spin_lock_bh(&backlog->lock);
        if (!qat_alg_try_enqueue(req)) {
                list_add_tail(&req->list, &backlog->list);
                ret = -EBUSY;
        }
        spin_unlock_bh(&backlog->lock);

        return ret;
}

int qat_alg_send_message(struct qat_alg_req *req)
{
        u32 flags = req->base->flags;

        if (flags & CRYPTO_TFM_REQ_MAY_BACKLOG)
                return qat_alg_send_message_maybacklog(req);
        else
                return qat_alg_send_message_retry(req);
}