/*
 * Copyright (C) 2015 Red Hat, Inc.
 * All Rights Reserved.
 *
 * 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 (including the
 * next paragraph) 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 OWNER(S) AND/OR ITS SUPPLIERS 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 <drm/drm_file.h>
#include <drm/drm_fourcc.h>

#include "virtgpu_drv.h"

static int virtio_gpu_gem_create(struct drm_file *file,
                                 struct drm_device *dev,
                                 struct virtio_gpu_object_params *params,
                                 struct drm_gem_object **obj_p,
                                 uint32_t *handle_p)
{
        struct virtio_gpu_device *vgdev = dev->dev_private;
        struct virtio_gpu_object *obj;
        int ret;
        u32 handle;

        ret = virtio_gpu_object_create(vgdev, params, &obj, NULL);
        if (ret < 0)
                return ret;

        ret = drm_gem_handle_create(file, &obj->base.base, &handle);
        if (ret) {
                drm_gem_object_release(&obj->base.base);
                return ret;
        }

        *obj_p = &obj->base.base;

        /* drop reference from allocate - handle holds it now */
        drm_gem_object_put(&obj->base.base);

        *handle_p = handle;
        return 0;
}

int virtio_gpu_mode_dumb_create(struct drm_file *file_priv,
                                struct drm_device *dev,
                                struct drm_mode_create_dumb *args)
{
        struct drm_gem_object *gobj;
        struct virtio_gpu_object_params params = { 0 };
        struct virtio_gpu_device *vgdev = dev->dev_private;
        int ret;
        uint32_t pitch;

        if (args->bpp != 32)
                return -EINVAL;

        pitch = args->width * 4;
        args->size = pitch * args->height;
        args->size = ALIGN(args->size, PAGE_SIZE);

        params.format = virtio_gpu_translate_format(DRM_FORMAT_HOST_XRGB8888);
        params.width = args->width;
        params.height = args->height;
        params.size = args->size;
        params.dumb = true;

        if (vgdev->has_resource_blob && !vgdev->has_virgl_3d) {
                params.blob_mem = VIRTGPU_BLOB_MEM_GUEST;
                params.blob_flags = VIRTGPU_BLOB_FLAG_USE_SHAREABLE;
                params.blob = true;
        }

        ret = virtio_gpu_gem_create(file_priv, dev, &params, &gobj,
                                    &args->handle);
        if (ret)
                goto fail;

        args->pitch = pitch;
        return ret;

fail:
        return ret;
}

int virtio_gpu_gem_object_open(struct drm_gem_object *obj,
                               struct drm_file *file)
{
        struct virtio_gpu_device *vgdev = obj->dev->dev_private;
        struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
        struct virtio_gpu_object_array *objs;

        if (!vgdev->has_virgl_3d)
                goto out_notify;

        /* the context might still be missing when the first ioctl is
         * DRM_IOCTL_MODE_CREATE_DUMB or DRM_IOCTL_PRIME_FD_TO_HANDLE
         */
        if (!vgdev->has_context_init)
                virtio_gpu_create_context(obj->dev, file);

        if (vfpriv->context_created) {
                objs = virtio_gpu_array_alloc(1);
                if (!objs)
                        return -ENOMEM;
                virtio_gpu_array_add_obj(objs, obj);

                virtio_gpu_cmd_context_attach_resource(vgdev, vfpriv->ctx_id, objs);
        }

out_notify:
        virtio_gpu_notify(vgdev);
        return 0;
}

void virtio_gpu_gem_object_close(struct drm_gem_object *obj,
                                 struct drm_file *file)
{
        struct virtio_gpu_device *vgdev = obj->dev->dev_private;
        struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
        struct virtio_gpu_object_array *objs;

        if (!vgdev->has_virgl_3d)
                return;

        objs = virtio_gpu_array_alloc(1);
        if (!objs)
                return;
        virtio_gpu_array_add_obj(objs, obj);

        virtio_gpu_cmd_context_detach_resource(vgdev, vfpriv->ctx_id,
                                               objs);
        virtio_gpu_notify(vgdev);
}

/* For drm panic */
struct virtio_gpu_object_array *virtio_gpu_panic_array_alloc(void)
{
        struct virtio_gpu_object_array *objs;

        objs = kmalloc_obj(struct virtio_gpu_object_array, GFP_ATOMIC);
        if (!objs)
                return NULL;

        objs->nents = 0;
        objs->total = 1;
        return objs;
}

struct virtio_gpu_object_array *virtio_gpu_array_alloc(u32 nents)
{
        struct virtio_gpu_object_array *objs;

        objs = kmalloc_flex(*objs, objs, nents);
        if (!objs)
                return NULL;

        objs->nents = 0;
        objs->total = nents;
        return objs;
}

static void virtio_gpu_array_free(struct virtio_gpu_object_array *objs)
{
        kfree(objs);
}

struct virtio_gpu_object_array*
virtio_gpu_array_from_handles(struct drm_file *drm_file, u32 *handles, u32 nents)
{
        struct virtio_gpu_object_array *objs;
        u32 i;

        objs = virtio_gpu_array_alloc(nents);
        if (!objs)
                return NULL;

        for (i = 0; i < nents; i++) {
                objs->objs[i] = drm_gem_object_lookup(drm_file, handles[i]);
                if (!objs->objs[i]) {
                        objs->nents = i;
                        virtio_gpu_array_put_free(objs);
                        return NULL;
                }
        }
        objs->nents = i;
        return objs;
}

void virtio_gpu_array_add_obj(struct virtio_gpu_object_array *objs,
                              struct drm_gem_object *obj)
{
        if (WARN_ON_ONCE(objs->nents == objs->total))
                return;

        drm_gem_object_get(obj);
        objs->objs[objs->nents] = obj;
        objs->nents++;
}

int virtio_gpu_array_lock_resv(struct virtio_gpu_object_array *objs)
{
        unsigned int i;
        int ret;

        if (objs->nents == 1) {
                ret = dma_resv_lock_interruptible(objs->objs[0]->resv, NULL);
        } else {
                ret = drm_gem_lock_reservations(objs->objs, objs->nents,
                                                &objs->ticket);
        }
        if (ret)
                return ret;

        for (i = 0; i < objs->nents; ++i) {
                ret = dma_resv_reserve_fences(objs->objs[i]->resv, 1);
                if (ret) {
                        virtio_gpu_array_unlock_resv(objs);
                        return ret;
                }
        }
        return ret;
}

void virtio_gpu_array_unlock_resv(struct virtio_gpu_object_array *objs)
{
        if (objs->nents == 1) {
                dma_resv_unlock(objs->objs[0]->resv);
        } else {
                drm_gem_unlock_reservations(objs->objs, objs->nents,
                                            &objs->ticket);
        }
}

void virtio_gpu_array_add_fence(struct virtio_gpu_object_array *objs,
                                struct dma_fence *fence)
{
        int i;

        for (i = 0; i < objs->nents; i++)
                dma_resv_add_fence(objs->objs[i]->resv, fence,
                                   DMA_RESV_USAGE_WRITE);
}

void virtio_gpu_array_put_free(struct virtio_gpu_object_array *objs)
{
        u32 i;

        if (!objs)
                return;

        for (i = 0; i < objs->nents; i++)
                drm_gem_object_put(objs->objs[i]);
        virtio_gpu_array_free(objs);
}

void virtio_gpu_array_put_free_delayed(struct virtio_gpu_device *vgdev,
                                       struct virtio_gpu_object_array *objs)
{
        spin_lock(&vgdev->obj_free_lock);
        list_add_tail(&objs->next, &vgdev->obj_free_list);
        spin_unlock(&vgdev->obj_free_lock);
        schedule_work(&vgdev->obj_free_work);
}

void virtio_gpu_array_put_free_work(struct work_struct *work)
{
        struct virtio_gpu_device *vgdev =
                container_of(work, struct virtio_gpu_device, obj_free_work);
        struct virtio_gpu_object_array *objs;

        spin_lock(&vgdev->obj_free_lock);
        while (!list_empty(&vgdev->obj_free_list)) {
                objs = list_first_entry(&vgdev->obj_free_list,
                                        struct virtio_gpu_object_array, next);
                list_del(&objs->next);
                spin_unlock(&vgdev->obj_free_lock);
                virtio_gpu_array_put_free(objs);
                spin_lock(&vgdev->obj_free_lock);
        }
        spin_unlock(&vgdev->obj_free_lock);
}