1 // SPDX-License-Identifier: GPL-2.0
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
9 #include <linux/shmem_fs.h>
13 static struct vkms_gem_object *__vkms_gem_create(struct drm_device *dev,
16 struct vkms_gem_object *obj;
19 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
21 return ERR_PTR(-ENOMEM);
23 size = roundup(size, PAGE_SIZE);
24 ret = drm_gem_object_init(dev, &obj->gem, size);
30 mutex_init(&obj->pages_lock);
35 void vkms_gem_free_object(struct drm_gem_object *obj)
37 struct vkms_gem_object *gem = container_of(obj, struct vkms_gem_object,
41 mutex_destroy(&gem->pages_lock);
42 drm_gem_object_release(obj);
46 int vkms_gem_fault(struct vm_fault *vmf)
48 struct vm_area_struct *vma = vmf->vma;
49 struct vkms_gem_object *obj = vma->vm_private_data;
50 unsigned long vaddr = vmf->address;
55 page_offset = (vaddr - vma->vm_start) >> PAGE_SHIFT;
56 num_pages = DIV_ROUND_UP(obj->gem.size, PAGE_SIZE);
58 if (page_offset > num_pages)
59 return VM_FAULT_SIGBUS;
62 mutex_lock(&obj->pages_lock);
64 get_page(obj->pages[page_offset]);
65 vmf->page = obj->pages[page_offset];
68 mutex_unlock(&obj->pages_lock);
71 struct address_space *mapping;
73 mapping = file_inode(obj->gem.filp)->i_mapping;
74 page = shmem_read_mapping_page(mapping, page_offset);
80 switch (PTR_ERR(page)) {
90 ret = VM_FAULT_SIGBUS;
93 WARN_ON(PTR_ERR(page));
94 ret = VM_FAULT_SIGBUS;
102 struct drm_gem_object *vkms_gem_create(struct drm_device *dev,
103 struct drm_file *file,
107 struct vkms_gem_object *obj;
110 if (!file || !dev || !handle)
111 return ERR_PTR(-EINVAL);
113 obj = __vkms_gem_create(dev, size);
115 return ERR_CAST(obj);
117 ret = drm_gem_handle_create(file, &obj->gem, handle);
118 drm_gem_object_put_unlocked(&obj->gem);
120 drm_gem_object_release(&obj->gem);
128 int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
129 struct drm_mode_create_dumb *args)
131 struct drm_gem_object *gem_obj;
134 if (!args || !dev || !file)
137 pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
138 size = pitch * args->height;
143 gem_obj = vkms_gem_create(dev, file, &args->handle, size);
145 return PTR_ERR(gem_obj);
147 args->size = gem_obj->size;
150 DRM_DEBUG_DRIVER("Created object of size %lld\n", size);
155 int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
156 u32 handle, u64 *offset)
158 struct drm_gem_object *obj;
161 obj = drm_gem_object_lookup(file, handle);
170 ret = drm_gem_create_mmap_offset(obj);
174 *offset = drm_vma_node_offset_addr(&obj->vma_node);
176 drm_gem_object_put_unlocked(obj);