tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2012 Red Hat
4 */
5
6#include <linux/dma-buf.h>
7#include <linux/vmalloc.h>
8
9#include <drm/drm_mode.h>
10#include <drm/drm_prime.h>
11
12#include "udl_drv.h"
13
14struct udl_gem_object *udl_gem_alloc_object(struct drm_device *dev,
15 size_t size)
16{
17 struct udl_gem_object *obj;
18
19 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
20 if (obj == NULL)
21 return NULL;
22
23 if (drm_gem_object_init(dev, &obj->base, size) != 0) {
24 kfree(obj);
25 return NULL;
26 }
27
28 obj->flags = UDL_BO_CACHEABLE;
29 return obj;
30}
31
32static int
33udl_gem_create(struct drm_file *file,
34 struct drm_device *dev,
35 uint64_t size,
36 uint32_t *handle_p)
37{
38 struct udl_gem_object *obj;
39 int ret;
40 u32 handle;
41
42 size = roundup(size, PAGE_SIZE);
43
44 obj = udl_gem_alloc_object(dev, size);
45 if (obj == NULL)
46 return -ENOMEM;
47
48 ret = drm_gem_handle_create(file, &obj->base, &handle);
49 if (ret) {
50 drm_gem_object_release(&obj->base);
51 kfree(obj);
52 return ret;
53 }
54
55 drm_gem_object_put_unlocked(&obj->base);
56 *handle_p = handle;
57 return 0;
58}
59
60static void update_vm_cache_attr(struct udl_gem_object *obj,
61 struct vm_area_struct *vma)
62{
63 DRM_DEBUG_KMS("flags = 0x%x\n", obj->flags);
64
65 /* non-cacheable as default. */
66 if (obj->flags & UDL_BO_CACHEABLE) {
67 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
68 } else if (obj->flags & UDL_BO_WC) {
69 vma->vm_page_prot =
70 pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
71 } else {
72 vma->vm_page_prot =
73 pgprot_noncached(vm_get_page_prot(vma->vm_flags));
74 }
75}
76
77int udl_dumb_create(struct drm_file *file,
78 struct drm_device *dev,
79 struct drm_mode_create_dumb *args)
80{
81 args->pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
82 args->size = args->pitch * args->height;
83 return udl_gem_create(file, dev,
84 args->size, &args->handle);
85}
86
87int udl_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
88{
89 int ret;
90
91 ret = drm_gem_mmap(filp, vma);
92 if (ret)
93 return ret;
94
95 vma->vm_flags &= ~VM_PFNMAP;
96 vma->vm_flags |= VM_MIXEDMAP;
97
98 update_vm_cache_attr(to_udl_bo(vma->vm_private_data), vma);
99
100 return ret;
101}
102
103vm_fault_t udl_gem_fault(struct vm_fault *vmf)
104{
105 struct vm_area_struct *vma = vmf->vma;
106 struct udl_gem_object *obj = to_udl_bo(vma->vm_private_data);
107 struct page *page;
108 unsigned int page_offset;
109
110 page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
111
112 if (!obj->pages)
113 return VM_FAULT_SIGBUS;
114
115 page = obj->pages[page_offset];
116 return vmf_insert_page(vma, vmf->address, page);
117}
118
119int udl_gem_get_pages(struct udl_gem_object *obj)
120{
121 struct page **pages;
122
123 if (obj->pages)
124 return 0;
125
126 pages = drm_gem_get_pages(&obj->base);
127 if (IS_ERR(pages))
128 return PTR_ERR(pages);
129
130 obj->pages = pages;
131
132 return 0;
133}
134
135void udl_gem_put_pages(struct udl_gem_object *obj)
136{
137 if (obj->base.import_attach) {
138 kvfree(obj->pages);
139 obj->pages = NULL;
140 return;
141 }
142
143 drm_gem_put_pages(&obj->base, obj->pages, false, false);
144 obj->pages = NULL;
145}
146
147int udl_gem_vmap(struct udl_gem_object *obj)
148{
149 int page_count = obj->base.size / PAGE_SIZE;
150 int ret;
151
152 if (obj->base.import_attach) {
153 obj->vmapping = dma_buf_vmap(obj->base.import_attach->dmabuf);
154 if (!obj->vmapping)
155 return -ENOMEM;
156 return 0;
157 }
158
159 ret = udl_gem_get_pages(obj);
160 if (ret)
161 return ret;
162
163 obj->vmapping = vmap(obj->pages, page_count, 0, PAGE_KERNEL);
164 if (!obj->vmapping)
165 return -ENOMEM;
166 return 0;
167}
168
169void udl_gem_vunmap(struct udl_gem_object *obj)
170{
171 if (obj->base.import_attach) {
172 dma_buf_vunmap(obj->base.import_attach->dmabuf, obj->vmapping);
173 return;
174 }
175
176 vunmap(obj->vmapping);
177
178 udl_gem_put_pages(obj);
179}
180
181void udl_gem_free_object(struct drm_gem_object *gem_obj)
182{
183 struct udl_gem_object *obj = to_udl_bo(gem_obj);
184
185 if (obj->vmapping)
186 udl_gem_vunmap(obj);
187
188 if (gem_obj->import_attach) {
189 drm_prime_gem_destroy(gem_obj, obj->sg);
190 put_device(gem_obj->dev->dev);
191 }
192
193 if (obj->pages)
194 udl_gem_put_pages(obj);
195
196 drm_gem_free_mmap_offset(gem_obj);
197}
198
199/* the dumb interface doesn't work with the GEM straight MMAP
200 interface, it expects to do MMAP on the drm fd, like normal */
201int udl_gem_mmap(struct drm_file *file, struct drm_device *dev,
202 uint32_t handle, uint64_t *offset)
203{
204 struct udl_gem_object *gobj;
205 struct drm_gem_object *obj;
206 struct udl_device *udl = to_udl(dev);
207 int ret = 0;
208
209 mutex_lock(&udl->gem_lock);
210 obj = drm_gem_object_lookup(file, handle);
211 if (obj == NULL) {
212 ret = -ENOENT;
213 goto unlock;
214 }
215 gobj = to_udl_bo(obj);
216
217 ret = udl_gem_get_pages(gobj);
218 if (ret)
219 goto out;
220 ret = drm_gem_create_mmap_offset(obj);
221 if (ret)
222 goto out;
223
224 *offset = drm_vma_node_offset_addr(&gobj->base.vma_node);
225
226out:
227 drm_gem_object_put_unlocked(&gobj->base);
228unlock:
229 mutex_unlock(&udl->gem_lock);
230 return ret;
231}