summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
blob: 3cf8aab23a39b6da27cd5056f9b5263ccc5e4e9c (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
/*
 * drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
 *
 * Copyright (C) 2011 Texas Instruments
 * Author: Rob Clark <rob.clark@linaro.org>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/dma-buf.h>

#include "omap_drv.h"

/* -----------------------------------------------------------------------------
 * DMABUF Export
 */

static struct sg_table *omap_gem_map_dma_buf(
		struct dma_buf_attachment *attachment,
		enum dma_data_direction dir)
{
	struct drm_gem_object *obj = attachment->dmabuf->priv;
	struct sg_table *sg;
	dma_addr_t paddr;
	int ret;

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

	/* camera, etc, need physically contiguous.. but we need a
	 * better way to know this..
	 */
	ret = omap_gem_get_paddr(obj, &paddr, true);
	if (ret)
		goto out;

	ret = sg_alloc_table(sg, 1, GFP_KERNEL);
	if (ret)
		goto out;

	sg_init_table(sg->sgl, 1);
	sg_dma_len(sg->sgl) = obj->size;
	sg_set_page(sg->sgl, pfn_to_page(PFN_DOWN(paddr)), obj->size, 0);
	sg_dma_address(sg->sgl) = paddr;

	/* this should be after _get_paddr() to ensure we have pages attached */
	omap_gem_dma_sync(obj, dir);

	return sg;
out:
	kfree(sg);
	return ERR_PTR(ret);
}

static void omap_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
		struct sg_table *sg, enum dma_data_direction dir)
{
	struct drm_gem_object *obj = attachment->dmabuf->priv;
	omap_gem_put_paddr(obj);
	sg_free_table(sg);
	kfree(sg);
}

static void omap_gem_dmabuf_release(struct dma_buf *buffer)
{
	struct drm_gem_object *obj = buffer->priv;
	/* release reference that was taken when dmabuf was exported
	 * in omap_gem_prime_set()..
	 */
	drm_gem_object_unreference_unlocked(obj);
}


static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer,
		enum dma_data_direction dir)
{
	struct drm_gem_object *obj = buffer->priv;
	struct page **pages;
	if (omap_gem_flags(obj) & OMAP_BO_TILED) {
		/* TODO we would need to pin at least part of the buffer to
		 * get de-tiled view.  For now just reject it.
		 */
		return -ENOMEM;
	}
	/* make sure we have the pages: */
	return omap_gem_get_pages(obj, &pages, true);
}

static void omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer,
		enum dma_data_direction dir)
{
	struct drm_gem_object *obj = buffer->priv;
	omap_gem_put_pages(obj);
}


static void *omap_gem_dmabuf_kmap_atomic(struct dma_buf *buffer,
		unsigned long page_num)
{
	struct drm_gem_object *obj = buffer->priv;
	struct page **pages;
	omap_gem_get_pages(obj, &pages, false);
	omap_gem_cpu_sync(obj, page_num);
	return kmap_atomic(pages[page_num]);
}

static void omap_gem_dmabuf_kunmap_atomic(struct dma_buf *buffer,
		unsigned long page_num, void *addr)
{
	kunmap_atomic(addr);
}

static void *omap_gem_dmabuf_kmap(struct dma_buf *buffer,
		unsigned long page_num)
{
	struct drm_gem_object *obj = buffer->priv;
	struct page **pages;
	omap_gem_get_pages(obj, &pages, false);
	omap_gem_cpu_sync(obj, page_num);
	return kmap(pages[page_num]);
}

static void omap_gem_dmabuf_kunmap(struct dma_buf *buffer,
		unsigned long page_num, void *addr)
{
	struct drm_gem_object *obj = buffer->priv;
	struct page **pages;
	omap_gem_get_pages(obj, &pages, false);
	kunmap(pages[page_num]);
}

static int omap_gem_dmabuf_mmap(struct dma_buf *buffer,
		struct vm_area_struct *vma)
{
	struct drm_gem_object *obj = buffer->priv;
	int ret = 0;

	if (WARN_ON(!obj->filp))
		return -EINVAL;

	ret = drm_gem_mmap_obj(obj, omap_gem_mmap_size(obj), vma);
	if (ret < 0)
		return ret;

	return omap_gem_mmap_obj(obj, vma);
}

static struct dma_buf_ops omap_dmabuf_ops = {
	.map_dma_buf = omap_gem_map_dma_buf,
	.unmap_dma_buf = omap_gem_unmap_dma_buf,
	.release = omap_gem_dmabuf_release,
	.begin_cpu_access = omap_gem_dmabuf_begin_cpu_access,
	.end_cpu_access = omap_gem_dmabuf_end_cpu_access,
	.kmap_atomic = omap_gem_dmabuf_kmap_atomic,
	.kunmap_atomic = omap_gem_dmabuf_kunmap_atomic,
	.kmap = omap_gem_dmabuf_kmap,
	.kunmap = omap_gem_dmabuf_kunmap,
	.mmap = omap_gem_dmabuf_mmap,
};

struct dma_buf *omap_gem_prime_export(struct drm_device *dev,
		struct drm_gem_object *obj, int flags)
{
	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

	exp_info.ops = &omap_dmabuf_ops;
	exp_info.size = obj->size;
	exp_info.flags = flags;
	exp_info.priv = obj;

	return dma_buf_export(&exp_info);
}

/* -----------------------------------------------------------------------------
 * DMABUF Import
 */

struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev,
					     struct dma_buf *dma_buf)
{
	struct dma_buf_attachment *attach;
	struct drm_gem_object *obj;
	struct sg_table *sgt;
	int ret;

	if (dma_buf->ops == &omap_dmabuf_ops) {
		obj = dma_buf->priv;
		if (obj->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);
			return obj;
		}
	}

	attach = dma_buf_attach(dma_buf, dev->dev);
	if (IS_ERR(attach))
		return ERR_CAST(attach);

	get_dma_buf(dma_buf);

	sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
	if (IS_ERR(sgt)) {
		ret = PTR_ERR(sgt);
		goto fail_detach;
	}

	obj = omap_gem_new_dmabuf(dev, dma_buf->size, sgt);
	if (IS_ERR(obj)) {
		ret = PTR_ERR(obj);
		goto fail_unmap;
	}

	obj->import_attach = attach;

	return obj;

fail_unmap:
	dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
fail_detach:
	dma_buf_detach(dma_buf, attach);
	dma_buf_put(dma_buf);

	return ERR_PTR(ret);
}
OpenPOWER on IntegriCloud