summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/vgem/vgem_drv.c
blob: 7ccbb03e98de5db2f04319d831963aacfc9498db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
/*
 * Copyright 2011 Red Hat, Inc.
 * Copyright © 2014 The Chromium OS Authors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software")
 * to deal in the software without restriction, including without limitation
 * on the rights to use, copy, modify, merge, publish, distribute, sub
 * license, and/or sell copies of the Software, and to permit persons to whom
 * them Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTIBILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES, OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT, OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors:
 *	Adam Jackson <ajax@redhat.com>
 *	Ben Widawsky <ben@bwidawsk.net>
 */

/**
 * This is vgem, a (non-hardware-backed) GEM service.  This is used by Mesa's
 * software renderer and the X server for efficient buffer sharing.
 */

#include <linux/module.h>
#include <linux/ramfs.h>
#include <linux/shmem_fs.h>
#include <linux/dma-buf.h>
#include "vgem_drv.h"

#define DRIVER_NAME	"vgem"
#define DRIVER_DESC	"Virtual GEM provider"
#define DRIVER_DATE	"20120112"
#define DRIVER_MAJOR	1
#define DRIVER_MINOR	0

static void vgem_gem_free_object(struct drm_gem_object *obj)
{
	struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);

	drm_gem_object_release(obj);
	kfree(vgem_obj);
}

static int vgem_gem_fault(struct vm_fault *vmf)
{
	struct vm_area_struct *vma = vmf->vma;
	struct drm_vgem_gem_object *obj = vma->vm_private_data;
	/* We don't use vmf->pgoff since that has the fake offset */
	unsigned long vaddr = vmf->address;
	struct page *page;

	page = shmem_read_mapping_page(file_inode(obj->base.filp)->i_mapping,
				       (vaddr - vma->vm_start) >> PAGE_SHIFT);
	if (!IS_ERR(page)) {
		vmf->page = page;
		return 0;
	} else switch (PTR_ERR(page)) {
		case -ENOSPC:
		case -ENOMEM:
			return VM_FAULT_OOM;
		case -EBUSY:
			return VM_FAULT_RETRY;
		case -EFAULT:
		case -EINVAL:
			return VM_FAULT_SIGBUS;
		default:
			WARN_ON_ONCE(PTR_ERR(page));
			return VM_FAULT_SIGBUS;
	}
}

static const struct vm_operations_struct vgem_gem_vm_ops = {
	.fault = vgem_gem_fault,
	.open = drm_gem_vm_open,
	.close = drm_gem_vm_close,
};

static int vgem_open(struct drm_device *dev, struct drm_file *file)
{
	struct vgem_file *vfile;
	int ret;

	vfile = kzalloc(sizeof(*vfile), GFP_KERNEL);
	if (!vfile)
		return -ENOMEM;

	file->driver_priv = vfile;

	ret = vgem_fence_open(vfile);
	if (ret) {
		kfree(vfile);
		return ret;
	}

	return 0;
}

static void vgem_preclose(struct drm_device *dev, struct drm_file *file)
{
	struct vgem_file *vfile = file->driver_priv;

	vgem_fence_close(vfile);
	kfree(vfile);
}

/* ioctls */

static struct drm_gem_object *vgem_gem_create(struct drm_device *dev,
					      struct drm_file *file,
					      unsigned int *handle,
					      unsigned long size)
{
	struct drm_vgem_gem_object *obj;
	int ret;

	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
	if (!obj)
		return ERR_PTR(-ENOMEM);

	ret = drm_gem_object_init(dev, &obj->base, roundup(size, PAGE_SIZE));
	if (ret)
		goto err_free;

	ret = drm_gem_handle_create(file, &obj->base, handle);
	drm_gem_object_unreference_unlocked(&obj->base);
	if (ret)
		goto err;

	return &obj->base;

err_free:
	kfree(obj);
err:
	return ERR_PTR(ret);
}

static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
				struct drm_mode_create_dumb *args)
{
	struct drm_gem_object *gem_object;
	u64 pitch, size;

	pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
	size = args->height * pitch;
	if (size == 0)
		return -EINVAL;

	gem_object = vgem_gem_create(dev, file, &args->handle, size);
	if (IS_ERR(gem_object))
		return PTR_ERR(gem_object);

	args->size = gem_object->size;
	args->pitch = pitch;

	DRM_DEBUG_DRIVER("Created object of size %lld\n", size);

	return 0;
}

static int vgem_gem_dumb_map(struct drm_file *file, struct drm_device *dev,
			     uint32_t handle, uint64_t *offset)
{
	struct drm_gem_object *obj;
	int ret;

	obj = drm_gem_object_lookup(file, handle);
	if (!obj)
		return -ENOENT;

	if (!obj->filp) {
		ret = -EINVAL;
		goto unref;
	}

	ret = drm_gem_create_mmap_offset(obj);
	if (ret)
		goto unref;

	*offset = drm_vma_node_offset_addr(&obj->vma_node);
unref:
	drm_gem_object_unreference_unlocked(obj);

	return ret;
}

static struct drm_ioctl_desc vgem_ioctls[] = {
	DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
	DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
};

static int vgem_mmap(struct file *filp, struct vm_area_struct *vma)
{
	unsigned long flags = vma->vm_flags;
	int ret;

	ret = drm_gem_mmap(filp, vma);
	if (ret)
		return ret;

	/* Keep the WC mmaping set by drm_gem_mmap() but our pages
	 * are ordinary and not special.
	 */
	vma->vm_flags = flags | VM_DONTEXPAND | VM_DONTDUMP;
	return 0;
}

static const struct file_operations vgem_driver_fops = {
	.owner		= THIS_MODULE,
	.open		= drm_open,
	.mmap		= vgem_mmap,
	.poll		= drm_poll,
	.read		= drm_read,
	.unlocked_ioctl = drm_ioctl,
	.release	= drm_release,
};

static int vgem_prime_pin(struct drm_gem_object *obj)
{
	long n_pages = obj->size >> PAGE_SHIFT;
	struct page **pages;

	/* Flush the object from the CPU cache so that importers can rely
	 * on coherent indirect access via the exported dma-address.
	 */
	pages = drm_gem_get_pages(obj);
	if (IS_ERR(pages))
		return PTR_ERR(pages);

	drm_clflush_pages(pages, n_pages);
	drm_gem_put_pages(obj, pages, true, false);

	return 0;
}

static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj)
{
	struct sg_table *st;
	struct page **pages;

	pages = drm_gem_get_pages(obj);
	if (IS_ERR(pages))
		return ERR_CAST(pages);

	st = drm_prime_pages_to_sg(pages, obj->size >> PAGE_SHIFT);
	drm_gem_put_pages(obj, pages, false, false);

	return st;
}

static void *vgem_prime_vmap(struct drm_gem_object *obj)
{
	long n_pages = obj->size >> PAGE_SHIFT;
	struct page **pages;
	void *addr;

	pages = drm_gem_get_pages(obj);
	if (IS_ERR(pages))
		return NULL;

	addr = vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL));
	drm_gem_put_pages(obj, pages, false, false);

	return addr;
}

static void vgem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
{
	vunmap(vaddr);
}

static int vgem_prime_mmap(struct drm_gem_object *obj,
			   struct vm_area_struct *vma)
{
	int ret;

	if (obj->size < vma->vm_end - vma->vm_start)
		return -EINVAL;

	if (!obj->filp)
		return -ENODEV;

	ret = obj->filp->f_op->mmap(obj->filp, vma);
	if (ret)
		return ret;

	fput(vma->vm_file);
	vma->vm_file = get_file(obj->filp);
	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
	vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));

	return 0;
}

static struct drm_driver vgem_driver = {
	.driver_features		= DRIVER_GEM | DRIVER_PRIME,
	.open				= vgem_open,
	.preclose			= vgem_preclose,
	.gem_free_object_unlocked	= vgem_gem_free_object,
	.gem_vm_ops			= &vgem_gem_vm_ops,
	.ioctls				= vgem_ioctls,
	.num_ioctls 			= ARRAY_SIZE(vgem_ioctls),
	.fops				= &vgem_driver_fops,

	.dumb_create			= vgem_gem_dumb_create,
	.dumb_map_offset		= vgem_gem_dumb_map,

	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
	.gem_prime_pin = vgem_prime_pin,
	.gem_prime_export = drm_gem_prime_export,
	.gem_prime_get_sg_table = vgem_prime_get_sg_table,
	.gem_prime_vmap = vgem_prime_vmap,
	.gem_prime_vunmap = vgem_prime_vunmap,
	.gem_prime_mmap = vgem_prime_mmap,

	.name	= DRIVER_NAME,
	.desc	= DRIVER_DESC,
	.date	= DRIVER_DATE,
	.major	= DRIVER_MAJOR,
	.minor	= DRIVER_MINOR,
};

static struct drm_device *vgem_device;

static int __init vgem_init(void)
{
	int ret;

	vgem_device = drm_dev_alloc(&vgem_driver, NULL);
	if (IS_ERR(vgem_device)) {
		ret = PTR_ERR(vgem_device);
		goto out;
	}

	ret  = drm_dev_register(vgem_device, 0);
	if (ret)
		goto out_unref;

	return 0;

out_unref:
	drm_dev_unref(vgem_device);
out:
	return ret;
}

static void __exit vgem_exit(void)
{
	drm_dev_unregister(vgem_device);
	drm_dev_unref(vgem_device);
}

module_init(vgem_init);
module_exit(vgem_exit);

MODULE_AUTHOR("Red Hat, Inc.");
MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL and additional rights");