1 // SPDX-License-Identifier: GPL-2.0+
3 #include <linux/shmem_fs.h>
7 static struct vkms_gem_object *__vkms_gem_create(struct drm_device *dev,
10 struct vkms_gem_object *obj;
13 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
15 return ERR_PTR(-ENOMEM);
17 size = roundup(size, PAGE_SIZE);
18 ret = drm_gem_object_init(dev, &obj->gem, size);
24 mutex_init(&obj->pages_lock);
29 void vkms_gem_free_object(struct drm_gem_object *obj)
31 struct vkms_gem_object *gem = container_of(obj, struct vkms_gem_object,
35 mutex_destroy(&gem->pages_lock);
36 drm_gem_object_release(obj);
40 int vkms_gem_fault(struct vm_fault *vmf)
42 struct vm_area_struct *vma = vmf->vma;
43 struct vkms_gem_object *obj = vma->vm_private_data;
44 unsigned long vaddr = vmf->address;
49 page_offset = (vaddr - vma->vm_start) >> PAGE_SHIFT;
50 num_pages = DIV_ROUND_UP(obj->gem.size, PAGE_SIZE);
52 if (page_offset > num_pages)
53 return VM_FAULT_SIGBUS;
56 mutex_lock(&obj->pages_lock);
58 get_page(obj->pages[page_offset]);
59 vmf->page = obj->pages[page_offset];
62 mutex_unlock(&obj->pages_lock);
65 struct address_space *mapping;
67 mapping = file_inode(obj->gem.filp)->i_mapping;
68 page = shmem_read_mapping_page(mapping, page_offset);
74 switch (PTR_ERR(page)) {
84 ret = VM_FAULT_SIGBUS;
87 WARN_ON(PTR_ERR(page));
88 ret = VM_FAULT_SIGBUS;
96 struct drm_gem_object *vkms_gem_create(struct drm_device *dev,
97 struct drm_file *file,
101 struct vkms_gem_object *obj;
104 if (!file || !dev || !handle)
105 return ERR_PTR(-EINVAL);
107 obj = __vkms_gem_create(dev, size);
109 return ERR_CAST(obj);
111 ret = drm_gem_handle_create(file, &obj->gem, handle);
112 drm_gem_object_put_unlocked(&obj->gem);
119 int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
120 struct drm_mode_create_dumb *args)
122 struct drm_gem_object *gem_obj;
125 if (!args || !dev || !file)
128 pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
129 size = pitch * args->height;
134 gem_obj = vkms_gem_create(dev, file, &args->handle, size);
136 return PTR_ERR(gem_obj);
138 args->size = gem_obj->size;
141 DRM_DEBUG_DRIVER("Created object of size %lld\n", size);
146 int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
147 u32 handle, u64 *offset)
149 struct drm_gem_object *obj;
152 obj = drm_gem_object_lookup(file, handle);
161 ret = drm_gem_create_mmap_offset(obj);
165 *offset = drm_vma_node_offset_addr(&obj->vma_node);
167 drm_gem_object_put_unlocked(obj);