summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/i915/i915_gem_dmabuf.c
blob: 7998da27c500744c78fd0897193b19f778244ca7 (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
/*
 * Copyright 2012 Red Hat Inc
 *
 * 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
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * 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 MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS 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:
 *	Dave Airlie <airlied@redhat.com>
 */
#include <drm/drmP.h>
#include "i915_drv.h"
#include <linux/dma-buf.h>

static struct drm_i915_gem_object *dma_buf_to_obj(struct dma_buf *buf)
{
	return to_intel_bo(buf->priv);
}

static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachment,
					     enum dma_data_direction dir)
{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
	struct sg_table *st;
	struct scatterlist *src, *dst;
	int ret, i;

	ret = i915_mutex_lock_interruptible(obj->base.dev);
	if (ret)
		goto err;

	ret = i915_gem_object_get_pages(obj);
	if (ret)
		goto err_unlock;

	i915_gem_object_pin_pages(obj);

	/* Copy sg so that we make an independent mapping */
	st = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
	if (st == NULL) {
		ret = -ENOMEM;
		goto err_unpin;
	}

	ret = sg_alloc_table(st, obj->pages->nents, GFP_KERNEL);
	if (ret)
		goto err_free;

	src = obj->pages->sgl;
	dst = st->sgl;
	for (i = 0; i < obj->pages->nents; i++) {
		sg_set_page(dst, sg_page(src), src->length, 0);
		dst = sg_next(dst);
		src = sg_next(src);
	}

	if (!dma_map_sg(attachment->dev, st->sgl, st->nents, dir)) {
		ret =-ENOMEM;
		goto err_free_sg;
	}

	mutex_unlock(&obj->base.dev->struct_mutex);
	return st;

err_free_sg:
	sg_free_table(st);
err_free:
	kfree(st);
err_unpin:
	i915_gem_object_unpin_pages(obj);
err_unlock:
	mutex_unlock(&obj->base.dev->struct_mutex);
err:
	return ERR_PTR(ret);
}

static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
				   struct sg_table *sg,
				   enum dma_data_direction dir)
{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);

	mutex_lock(&obj->base.dev->struct_mutex);

	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
	sg_free_table(sg);
	kfree(sg);

	i915_gem_object_unpin_pages(obj);

	mutex_unlock(&obj->base.dev->struct_mutex);
}

static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
	struct drm_device *dev = obj->base.dev;
	struct sg_page_iter sg_iter;
	struct page **pages;
	int ret, i;

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ERR_PTR(ret);

	if (obj->dma_buf_vmapping) {
		obj->vmapping_count++;
		goto out_unlock;
	}

	ret = i915_gem_object_get_pages(obj);
	if (ret)
		goto err;

	i915_gem_object_pin_pages(obj);

	ret = -ENOMEM;

	pages = drm_malloc_ab(obj->base.size >> PAGE_SHIFT, sizeof(*pages));
	if (pages == NULL)
		goto err_unpin;

	i = 0;
	for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0)
		pages[i++] = sg_page_iter_page(&sg_iter);

	obj->dma_buf_vmapping = vmap(pages, i, 0, PAGE_KERNEL);
	drm_free_large(pages);

	if (!obj->dma_buf_vmapping)
		goto err_unpin;

	obj->vmapping_count = 1;
out_unlock:
	mutex_unlock(&dev->struct_mutex);
	return obj->dma_buf_vmapping;

err_unpin:
	i915_gem_object_unpin_pages(obj);
err:
	mutex_unlock(&dev->struct_mutex);
	return ERR_PTR(ret);
}

static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
	struct drm_device *dev = obj->base.dev;

	mutex_lock(&dev->struct_mutex);
	if (--obj->vmapping_count == 0) {
		vunmap(obj->dma_buf_vmapping);
		obj->dma_buf_vmapping = NULL;

		i915_gem_object_unpin_pages(obj);
	}
	mutex_unlock(&dev->struct_mutex);
}

static void *i915_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
{
	return NULL;
}

static void i915_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
{

}
static void *i915_gem_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
{
	return NULL;
}

static void i915_gem_dmabuf_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
{

}

static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
{
	return -EINVAL;
}

static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, size_t start, size_t length, enum dma_data_direction direction)
{
	struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
	struct drm_device *dev = obj->base.dev;
	int ret;
	bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE);

	ret = i915_mutex_lock_interruptible(dev);
	if (ret)
		return ret;

	ret = i915_gem_object_set_to_cpu_domain(obj, write);
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

static const struct dma_buf_ops i915_dmabuf_ops =  {
	.map_dma_buf = i915_gem_map_dma_buf,
	.unmap_dma_buf = i915_gem_unmap_dma_buf,
	.release = drm_gem_dmabuf_release,
	.kmap = i915_gem_dmabuf_kmap,
	.kmap_atomic = i915_gem_dmabuf_kmap_atomic,
	.kunmap = i915_gem_dmabuf_kunmap,
	.kunmap_atomic = i915_gem_dmabuf_kunmap_atomic,
	.mmap = i915_gem_dmabuf_mmap,
	.vmap = i915_gem_dmabuf_vmap,
	.vunmap = i915_gem_dmabuf_vunmap,
	.begin_cpu_access = i915_gem_begin_cpu_access,
};

struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
				      struct drm_gem_object *gem_obj, int flags)
{
	struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

	exp_info.ops = &i915_dmabuf_ops;
	exp_info.size = gem_obj->size;
	exp_info.flags = flags;
	exp_info.priv = gem_obj;


	if (obj->ops->dmabuf_export) {
		int ret = obj->ops->dmabuf_export(obj);
		if (ret)
			return ERR_PTR(ret);
	}

	return dma_buf_export(&exp_info);
}

static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
{
	struct sg_table *sg;

	sg = dma_buf_map_attachment(obj->base.import_attach, DMA_BIDIRECTIONAL);
	if (IS_ERR(sg))
		return PTR_ERR(sg);

	obj->pages = sg;
	obj->has_dma_mapping = true;
	return 0;
}

static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj)
{
	dma_buf_unmap_attachment(obj->base.import_attach,
				 obj->pages, DMA_BIDIRECTIONAL);
	obj->has_dma_mapping = false;
}

static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = {
	.get_pages = i915_gem_object_get_pages_dmabuf,
	.put_pages = i915_gem_object_put_pages_dmabuf,
};

struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
					     struct dma_buf *dma_buf)
{
	struct dma_buf_attachment *attach;
	struct drm_i915_gem_object *obj;
	int ret;

	/* is this one of own objects? */
	if (dma_buf->ops == &i915_dmabuf_ops) {
		obj = dma_buf_to_obj(dma_buf);
		/* is it from our device? */
		if (obj->base.dev == dev) {
			/*
			 * Importing dmabuf exported from out own gem increases
			 * refcount on gem itself instead of f_count of dmabuf.
			 */
			drm_gem_object_reference(&obj->base);
			return &obj->base;
		}
	}

	/* need to attach */
	attach = dma_buf_attach(dma_buf, dev->dev);
	if (IS_ERR(attach))
		return ERR_CAST(attach);

	get_dma_buf(dma_buf);

	obj = i915_gem_object_alloc(dev);
	if (obj == NULL) {
		ret = -ENOMEM;
		goto fail_detach;
	}

	drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
	i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
	obj->base.import_attach = attach;

	return &obj->base;

fail_detach:
	dma_buf_detach(dma_buf, attach);
	dma_buf_put(dma_buf);

	return ERR_PTR(ret);
}