igt_mmap.c

 1/*
 2 * SPDX-License-Identifier: MIT
 3 *
 4 * Copyright © 2019 Intel Corporation
 5 */
 6
 7#include <drm/drm_file.h>
 8
 9#include "i915_drv.h"
10#include "igt_mmap.h"
11
12unsigned long igt_mmap_offset(struct drm_i915_private *i915,
13			      u64 offset,
14			      unsigned long size,
15			      unsigned long prot,
16			      unsigned long flags)
17{
18	struct drm_vma_offset_node *node;
19	struct file *file;
20	unsigned long addr;
21	int err;
22
23	/* no need to refcount, we own this object */
24	drm_vma_offset_lock_lookup(i915->drm.vma_offset_manager);
25	node = drm_vma_offset_exact_lookup_locked(i915->drm.vma_offset_manager,
26						  offset / PAGE_SIZE, size / PAGE_SIZE);
27	drm_vma_offset_unlock_lookup(i915->drm.vma_offset_manager);
28
29	if (GEM_WARN_ON(!node)) {
30		pr_info("Failed to lookup %llx\n", offset);
31		return -ENOENT;
32	}
33
34	/* Pretend to open("/dev/dri/card0") */
35	file = mock_drm_getfile(i915->drm.primary, O_RDWR);
36	if (IS_ERR(file))
37		return PTR_ERR(file);
38
39	err = drm_vma_node_allow(node, file->private_data);
40	if (err) {
41		addr = err;
42		goto out_file;
43	}
44
45	addr = vm_mmap(file, 0, drm_vma_node_size(node) << PAGE_SHIFT,
46		       prot, flags, drm_vma_node_offset_addr(node));
47
48	drm_vma_node_revoke(node, file->private_data);
49out_file:
50	fput(file);
51	return addr;
52}