/*
 * Copyright 2014 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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/slab.h>
#include <linux/list.h>
#include "kfd_device_queue_manager.h"
#include "kfd_priv.h"
#include "kfd_kernel_queue.h"

static inline struct process_queue_node *get_queue_by_qid(
                        struct process_queue_manager *pqm, unsigned int qid)
{
        struct process_queue_node *pqn;

        list_for_each_entry(pqn, &pqm->queues, process_queue_list) {
                if ((pqn->q && pqn->q->properties.queue_id == qid) ||
                    (pqn->kq && pqn->kq->queue->properties.queue_id == qid))
                        return pqn;
        }

        return NULL;
}

static int find_available_queue_slot(struct process_queue_manager *pqm,
                                        unsigned int *qid)
{
        unsigned long found;

        found = find_first_zero_bit(pqm->queue_slot_bitmap,
                        KFD_MAX_NUM_OF_QUEUES_PER_PROCESS);

        pr_debug("The new slot id %lu\n", found);

        if (found >= KFD_MAX_NUM_OF_QUEUES_PER_PROCESS) {
                pr_info("Cannot open more queues for process with pasid %d\n",
                                pqm->process->pasid);
                return -ENOMEM;
        }

        set_bit(found, pqm->queue_slot_bitmap);
        *qid = found;

        return 0;
}

int pqm_init(struct process_queue_manager *pqm, struct kfd_process *p)
{
        INIT_LIST_HEAD(&pqm->queues);
        pqm->queue_slot_bitmap =
                        kzalloc(DIV_ROUND_UP(KFD_MAX_NUM_OF_QUEUES_PER_PROCESS,
                                        BITS_PER_BYTE), GFP_KERNEL);
        if (!pqm->queue_slot_bitmap)
                return -ENOMEM;
        pqm->process = p;

        return 0;
}

void pqm_uninit(struct process_queue_manager *pqm)
{
        int retval;
        struct process_queue_node *pqn, *next;

        list_for_each_entry_safe(pqn, next, &pqm->queues, process_queue_list) {
                retval = pqm_destroy_queue(
                                pqm,
                                (pqn->q != NULL) ?
                                        pqn->q->properties.queue_id :
                                        pqn->kq->queue->properties.queue_id);

                if (retval != 0) {
                        pr_err("failed to destroy queue\n");
                        return;
                }
        }
        kfree(pqm->queue_slot_bitmap);
        pqm->queue_slot_bitmap = NULL;
}

static int create_cp_queue(struct process_queue_manager *pqm,
                                struct kfd_dev *dev, struct queue **q,
                                struct queue_properties *q_properties,
                                struct file *f, unsigned int qid)
{
        int retval;

        /* Doorbell initialized in user space*/
        q_properties->doorbell_ptr = NULL;

        q_properties->doorbell_off =
                        kfd_queue_id_to_doorbell(dev, pqm->process, qid);

        /* let DQM handle it*/
        q_properties->vmid = 0;
        q_properties->queue_id = qid;

        retval = init_queue(q, q_properties);
        if (retval != 0)
                return retval;

        (*q)->device = dev;
        (*q)->process = pqm->process;

        pr_debug("PQM After init queue");

        return retval;
}

int pqm_create_queue(struct process_queue_manager *pqm,
                            struct kfd_dev *dev,
                            struct file *f,
                            struct queue_properties *properties,
                            unsigned int flags,
                            enum kfd_queue_type type,
                            unsigned int *qid)
{
        int retval;
        struct kfd_process_device *pdd;
        struct queue_properties q_properties;
        struct queue *q;
        struct process_queue_node *pqn;
        struct kernel_queue *kq;
        int num_queues = 0;
        struct queue *cur;

        memcpy(&q_properties, properties, sizeof(struct queue_properties));
        q = NULL;
        kq = NULL;

        pdd = kfd_get_process_device_data(dev, pqm->process);
        if (!pdd) {
                pr_err("Process device data doesn't exist\n");
                return -1;
        }

        /*
         * for debug process, verify that it is within the static queues limit
         * currently limit is set to half of the total avail HQD slots
         * If we are just about to create DIQ, the is_debug flag is not set yet
         * Hence we also check the type as well
         */
        if ((pdd->qpd.is_debug) ||
                (type == KFD_QUEUE_TYPE_DIQ)) {
                list_for_each_entry(cur, &pdd->qpd.queues_list, list)
                        num_queues++;
                if (num_queues >= dev->device_info->max_no_of_hqd/2)
                        return -ENOSPC;
        }

        retval = find_available_queue_slot(pqm, qid);
        if (retval != 0)
                return retval;

        if (list_empty(&pqm->queues)) {
                pdd->qpd.pqm = pqm;
                dev->dqm->ops.register_process(dev->dqm, &pdd->qpd);
        }

        pqn = kzalloc(sizeof(*pqn), GFP_KERNEL);
        if (!pqn) {
                retval = -ENOMEM;
                goto err_allocate_pqn;
        }

        switch (type) {
        case KFD_QUEUE_TYPE_SDMA:
        case KFD_QUEUE_TYPE_COMPUTE:
                /* check if there is over subscription */
                if ((sched_policy == KFD_SCHED_POLICY_HWS_NO_OVERSUBSCRIPTION) &&
                ((dev->dqm->processes_count >= VMID_PER_DEVICE) ||
                (dev->dqm->queue_count >= get_queues_num(dev->dqm)))) {
                        pr_err("Over-subscription is not allowed in radeon_kfd.sched_policy == 1\n");
                        retval = -EPERM;
                        goto err_create_queue;
                }

                retval = create_cp_queue(pqm, dev, &q, &q_properties, f, *qid);
                if (retval != 0)
                        goto err_create_queue;
                pqn->q = q;
                pqn->kq = NULL;
                retval = dev->dqm->ops.create_queue(dev->dqm, q, &pdd->qpd,
                                                &q->properties.vmid);
                pr_debug("DQM returned %d for create_queue\n", retval);
                print_queue(q);
                break;
        case KFD_QUEUE_TYPE_DIQ:
                kq = kernel_queue_init(dev, KFD_QUEUE_TYPE_DIQ);
                if (!kq) {
                        retval = -ENOMEM;
                        goto err_create_queue;
                }
                kq->queue->properties.queue_id = *qid;
                pqn->kq = kq;
                pqn->q = NULL;
                retval = dev->dqm->ops.create_kernel_queue(dev->dqm,
                                                        kq, &pdd->qpd);
                break;
        default:
                WARN(1, "Invalid queue type %d", type);
                retval = -EINVAL;
        }

        if (retval != 0) {
                pr_err("DQM create queue failed\n");
                goto err_create_queue;
        }

        pr_debug("PQM After DQM create queue\n");

        list_add(&pqn->process_queue_list, &pqm->queues);

        if (q) {
                *properties = q->properties;
                pr_debug("PQM done creating queue\n");
                print_queue_properties(properties);
        }

        return retval;

err_create_queue:
        kfree(pqn);
err_allocate_pqn:
        /* check if queues list is empty unregister process from device */
        clear_bit(*qid, pqm->queue_slot_bitmap);
        if (list_empty(&pqm->queues))
                dev->dqm->ops.unregister_process(dev->dqm, &pdd->qpd);
        return retval;
}

int pqm_destroy_queue(struct process_queue_manager *pqm, unsigned int qid)
{
        struct process_queue_node *pqn;
        struct kfd_process_device *pdd;
        struct device_queue_manager *dqm;
        struct kfd_dev *dev;
        int retval;

        dqm = NULL;

        retval = 0;

        pqn = get_queue_by_qid(pqm, qid);
        if (!pqn) {
                pr_err("Queue id does not match any known queue\n");
                return -EINVAL;
        }

        dev = NULL;
        if (pqn->kq)
                dev = pqn->kq->dev;
        if (pqn->q)
                dev = pqn->q->device;
        if (WARN_ON(!dev))
                return -ENODEV;

        pdd = kfd_get_process_device_data(dev, pqm->process);
        if (!pdd) {
                pr_err("Process device data doesn't exist\n");
                return -1;
        }

        if (pqn->kq) {
                /* destroy kernel queue (DIQ) */
                dqm = pqn->kq->dev->dqm;
                dqm->ops.destroy_kernel_queue(dqm, pqn->kq, &pdd->qpd);
                kernel_queue_uninit(pqn->kq);
        }

        if (pqn->q) {
                dqm = pqn->q->device->dqm;
                retval = dqm->ops.destroy_queue(dqm, &pdd->qpd, pqn->q);
                if (retval != 0)
                        return retval;

                uninit_queue(pqn->q);
        }

        list_del(&pqn->process_queue_list);
        kfree(pqn);
        clear_bit(qid, pqm->queue_slot_bitmap);

        if (list_empty(&pqm->queues))
                dqm->ops.unregister_process(dqm, &pdd->qpd);

        return retval;
}

int pqm_update_queue(struct process_queue_manager *pqm, unsigned int qid,
                        struct queue_properties *p)
{
        int retval;
        struct process_queue_node *pqn;

        pqn = get_queue_by_qid(pqm, qid);
        if (!pqn) {
                pr_debug("No queue %d exists for update operation\n", qid);
                return -EFAULT;
        }

        pqn->q->properties.queue_address = p->queue_address;
        pqn->q->properties.queue_size = p->queue_size;
        pqn->q->properties.queue_percent = p->queue_percent;
        pqn->q->properties.priority = p->priority;

        retval = pqn->q->device->dqm->ops.update_queue(pqn->q->device->dqm,
                                                        pqn->q);
        if (retval != 0)
                return retval;

        return 0;
}

struct kernel_queue *pqm_get_kernel_queue(
                                        struct process_queue_manager *pqm,
                                        unsigned int qid)
{
        struct process_queue_node *pqn;

        pqn = get_queue_by_qid(pqm, qid);
        if (pqn && pqn->kq)
                return pqn->kq;

        return NULL;
}