1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /**************************************************************************
3  *
4  * Copyright 2009-2011 VMware, Inc., Palo Alto, CA., USA
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 
28 #include "vmwgfx_drv.h"
29 
30 static int vmw_bo_vm_lookup(struct ttm_device *bdev,
31 				   struct drm_file *filp,
32 				   unsigned long offset,
33 				   unsigned long pages,
34 				   struct ttm_buffer_object **p_bo)
35 {
36 	struct vmw_private *dev_priv = container_of(bdev, struct vmw_private, bdev);
37 	struct drm_device *drm = &dev_priv->drm;
38 	struct drm_vma_offset_node *node;
39 	int ret;
40 
41 	*p_bo = NULL;
42 
43 	drm_vma_offset_lock_lookup(bdev->vma_manager);
44 
45 	node = drm_vma_offset_lookup_locked(bdev->vma_manager, offset, pages);
46 	if (likely(node)) {
47 		*p_bo = container_of(node, struct ttm_buffer_object,
48 				  base.vma_node);
49 		*p_bo = ttm_bo_get_unless_zero(*p_bo);
50 	}
51 
52 	drm_vma_offset_unlock_lookup(bdev->vma_manager);
53 
54 	if (!*p_bo) {
55 		drm_err(drm, "Could not find buffer object to map\n");
56 		return -EINVAL;
57 	}
58 
59 	if (!drm_vma_node_is_allowed(node, filp)) {
60 		ret = -EACCES;
61 		goto out_no_access;
62 	}
63 
64 	return 0;
65 out_no_access:
66 	ttm_bo_put(*p_bo);
67 	return ret;
68 }
69 
70 int vmw_mmap(struct file *filp, struct vm_area_struct *vma)
71 {
72 	static const struct vm_operations_struct vmw_vm_ops = {
73 		.pfn_mkwrite = vmw_bo_vm_mkwrite,
74 		.page_mkwrite = vmw_bo_vm_mkwrite,
75 		.fault = vmw_bo_vm_fault,
76 		.open = ttm_bo_vm_open,
77 		.close = ttm_bo_vm_close,
78 	};
79 	struct drm_file *file_priv = filp->private_data;
80 	struct vmw_private *dev_priv = vmw_priv(file_priv->minor->dev);
81 	struct ttm_device *bdev = &dev_priv->bdev;
82 	struct ttm_buffer_object *bo;
83 	int ret;
84 
85 	if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET_START))
86 		return -EINVAL;
87 
88 	ret = vmw_bo_vm_lookup(bdev, file_priv, vma->vm_pgoff, vma_pages(vma), &bo);
89 	if (unlikely(ret != 0))
90 		return ret;
91 
92 	ret = ttm_bo_mmap_obj(vma, bo);
93 	if (unlikely(ret != 0))
94 		goto out_unref;
95 
96 	vma->vm_ops = &vmw_vm_ops;
97 
98 	/* Use VM_PFNMAP rather than VM_MIXEDMAP if not a COW mapping */
99 	if (!is_cow_mapping(vma->vm_flags))
100 		vm_flags_mod(vma, VM_PFNMAP, VM_MIXEDMAP);
101 
102 	ttm_bo_put(bo); /* release extra ref taken by ttm_bo_mmap_obj() */
103 
104 	return 0;
105 
106 out_unref:
107 	ttm_bo_put(bo);
108 	return ret;
109 }
110 
111