/*
 * SPDX-License-Identifier: MIT
 *
 * Copyright © 2019 Intel Corporation
 */

#include <drm/drm_file.h>

#include "i915_drv.h"
#include "igt_mmap.h"

unsigned long igt_mmap_offset(struct drm_i915_private *i915,
                              u64 offset,
                              unsigned long size,
                              unsigned long prot,
                              unsigned long flags)
{
        struct drm_vma_offset_node *node;
        struct file *file;
        unsigned long addr;
        int err;

        /* no need to refcount, we own this object */
        drm_vma_offset_lock_lookup(i915->drm.vma_offset_manager);
        node = drm_vma_offset_exact_lookup_locked(i915->drm.vma_offset_manager,
                                                  offset / PAGE_SIZE, size / PAGE_SIZE);
        drm_vma_offset_unlock_lookup(i915->drm.vma_offset_manager);

        if (GEM_WARN_ON(!node)) {
                pr_info("Failed to lookup %llx\n", offset);
                return -ENOENT;
        }

        /* Pretend to open("/dev/dri/card0") */
        file = mock_drm_getfile(i915->drm.primary, O_RDWR);
        if (IS_ERR(file))
                return PTR_ERR(file);

        err = drm_vma_node_allow(node, file->private_data);
        if (err) {
                addr = err;
                goto out_file;
        }

        addr = vm_mmap(file, 0, drm_vma_node_size(node) << PAGE_SHIFT,
                       prot, flags, drm_vma_node_offset_addr(node));

        drm_vma_node_revoke(node, file->private_data);
out_file:
        fput(file);
        return addr;
}