// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2013 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 */

#include <linux/dma-buf.h>

#include <drm/drm_drv.h>
#include <drm/drm_prime.h>

#include "msm_drv.h"
#include "msm_gem.h"

struct sg_table *msm_gem_prime_get_sg_table(struct drm_gem_object *obj)
{
        struct msm_gem_object *msm_obj = to_msm_bo(obj);
        size_t npages = obj->size >> PAGE_SHIFT;

        if (msm_obj->flags & MSM_BO_NO_SHARE)
                return ERR_PTR(-EINVAL);

        if (WARN_ON(!msm_obj->pages))  /* should have already pinned! */
                return ERR_PTR(-ENOMEM);

        return drm_prime_pages_to_sg(obj->dev, msm_obj->pages, npages);
}

int msm_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map)
{
        void *vaddr;

        vaddr = msm_gem_get_vaddr_locked(obj);
        if (IS_ERR(vaddr))
                return PTR_ERR(vaddr);
        iosys_map_set_vaddr(map, vaddr);

        return 0;
}

void msm_gem_prime_vunmap(struct drm_gem_object *obj, struct iosys_map *map)
{
        msm_gem_put_vaddr_locked(obj);
}

static void msm_gem_dmabuf_release(struct dma_buf *dma_buf)
{
        struct drm_gem_object *obj = dma_buf->priv;

        msm_gem_vma_put(obj);
        drm_gem_dmabuf_release(dma_buf);
}

static const struct dma_buf_ops msm_gem_prime_dmabuf_ops =  {
        .attach = drm_gem_map_attach,
        .detach = drm_gem_map_detach,
        .map_dma_buf = drm_gem_map_dma_buf,
        .unmap_dma_buf = drm_gem_unmap_dma_buf,
        .release = msm_gem_dmabuf_release,
        .mmap = drm_gem_dmabuf_mmap,
        .vmap = drm_gem_dmabuf_vmap,
        .vunmap = drm_gem_dmabuf_vunmap,
};

struct drm_gem_object *msm_gem_prime_import(struct drm_device *dev,
                                            struct dma_buf *buf)
{
        if (buf->ops == &msm_gem_prime_dmabuf_ops) {
                struct drm_gem_object *obj = buf->priv;
                if (obj->dev == dev) {
                        /*
                         * Importing dmabuf exported from our own gem increases
                         * refcount on gem itself instead of f_count of dmabuf.
                         */
                        drm_gem_object_get(obj);
                        return obj;
                }
        }

        return drm_gem_prime_import(dev, buf);
}

struct drm_gem_object *msm_gem_prime_import_sg_table(struct drm_device *dev,
                struct dma_buf_attachment *attach, struct sg_table *sg)
{
        return msm_gem_import(dev, attach->dmabuf, sg);
}

struct dma_buf *msm_gem_prime_export(struct drm_gem_object *obj, int flags)
{
        if (to_msm_bo(obj)->flags & MSM_BO_NO_SHARE)
                return ERR_PTR(-EPERM);

        msm_gem_vma_get(obj);

        struct drm_device *dev = obj->dev;
        struct dma_buf_export_info exp_info = {
                .exp_name = KBUILD_MODNAME, /* white lie for debug */
                .owner = dev->driver->fops->owner,
                .ops = &msm_gem_prime_dmabuf_ops,
                .size = obj->size,
                .flags = flags,
                .priv = obj,
                .resv = obj->resv,
        };

        return drm_gem_dmabuf_export(dev, &exp_info);
}

int msm_gem_prime_pin(struct drm_gem_object *obj)
{
        struct page **pages;
        int ret = 0;

        if (drm_gem_is_imported(obj))
                return 0;

        if (to_msm_bo(obj)->flags & MSM_BO_NO_SHARE)
                return -EINVAL;

        pages = msm_gem_pin_pages_locked(obj);
        if (IS_ERR(pages))
                ret = PTR_ERR(pages);

        return ret;
}

void msm_gem_prime_unpin(struct drm_gem_object *obj)
{
        if (drm_gem_is_imported(obj))
                return;

        msm_gem_unpin_pages_locked(obj);
}