summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/udl/udl_dmabuf.c
blob: 556f62662aa92b41fefb738c1036dbd2eef18432 (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
/*
 * udl_dmabuf.c
 *
 * Copyright (c) 2014 The Chromium OS Authors
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 *
 * 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 <drm/drmP.h>
#include "udl_drv.h"
#include <linux/shmem_fs.h>
#include <linux/dma-buf.h>

struct udl_drm_dmabuf_attachment {
	struct sg_table sgt;
	enum dma_data_direction dir;
	bool is_mapped;
};

static int udl_attach_dma_buf(struct dma_buf *dmabuf,
			      struct dma_buf_attachment *attach)
{
	struct udl_drm_dmabuf_attachment *udl_attach;

	DRM_DEBUG_PRIME("[DEV:%s] size:%zd\n", dev_name(attach->dev),
			attach->dmabuf->size);

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

	udl_attach->dir = DMA_NONE;
	attach->priv = udl_attach;

	return 0;
}

static void udl_detach_dma_buf(struct dma_buf *dmabuf,
			       struct dma_buf_attachment *attach)
{
	struct udl_drm_dmabuf_attachment *udl_attach = attach->priv;
	struct sg_table *sgt;

	if (!udl_attach)
		return;

	DRM_DEBUG_PRIME("[DEV:%s] size:%zd\n", dev_name(attach->dev),
			attach->dmabuf->size);

	sgt = &udl_attach->sgt;

	if (udl_attach->dir != DMA_NONE)
		dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
				udl_attach->dir);

	sg_free_table(sgt);
	kfree(udl_attach);
	attach->priv = NULL;
}

static struct sg_table *udl_map_dma_buf(struct dma_buf_attachment *attach,
					enum dma_data_direction dir)
{
	struct udl_drm_dmabuf_attachment *udl_attach = attach->priv;
	struct udl_gem_object *obj = to_udl_bo(attach->dmabuf->priv);
	struct drm_device *dev = obj->base.dev;
	struct udl_device *udl = dev->dev_private;
	struct scatterlist *rd, *wr;
	struct sg_table *sgt = NULL;
	unsigned int i;
	int page_count;
	int nents, ret;

	DRM_DEBUG_PRIME("[DEV:%s] size:%zd dir=%d\n", dev_name(attach->dev),
			attach->dmabuf->size, dir);

	/* just return current sgt if already requested. */
	if (udl_attach->dir == dir && udl_attach->is_mapped)
		return &udl_attach->sgt;

	if (!obj->pages) {
		ret = udl_gem_get_pages(obj);
		if (ret) {
			DRM_ERROR("failed to map pages.\n");
			return ERR_PTR(ret);
		}
	}

	page_count = obj->base.size / PAGE_SIZE;
	obj->sg = drm_prime_pages_to_sg(obj->pages, page_count);
	if (IS_ERR(obj->sg)) {
		DRM_ERROR("failed to allocate sgt.\n");
		return ERR_CAST(obj->sg);
	}

	sgt = &udl_attach->sgt;

	ret = sg_alloc_table(sgt, obj->sg->orig_nents, GFP_KERNEL);
	if (ret) {
		DRM_ERROR("failed to alloc sgt.\n");
		return ERR_PTR(-ENOMEM);
	}

	mutex_lock(&udl->gem_lock);

	rd = obj->sg->sgl;
	wr = sgt->sgl;
	for (i = 0; i < sgt->orig_nents; ++i) {
		sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
		rd = sg_next(rd);
		wr = sg_next(wr);
	}

	if (dir != DMA_NONE) {
		nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
		if (!nents) {
			DRM_ERROR("failed to map sgl with iommu.\n");
			sg_free_table(sgt);
			sgt = ERR_PTR(-EIO);
			goto err_unlock;
		}
	}

	udl_attach->is_mapped = true;
	udl_attach->dir = dir;
	attach->priv = udl_attach;

err_unlock:
	mutex_unlock(&udl->gem_lock);
	return sgt;
}

static void udl_unmap_dma_buf(struct dma_buf_attachment *attach,
			      struct sg_table *sgt,
			      enum dma_data_direction dir)
{
	/* Nothing to do. */
	DRM_DEBUG_PRIME("[DEV:%s] size:%zd dir:%d\n", dev_name(attach->dev),
			attach->dmabuf->size, dir);
}

static void *udl_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
{
	/* TODO */

	return NULL;
}

static void udl_dmabuf_kunmap(struct dma_buf *dma_buf,
			      unsigned long page_num, void *addr)
{
	/* TODO */
}

static int udl_dmabuf_mmap(struct dma_buf *dma_buf,
			   struct vm_area_struct *vma)
{
	/* TODO */

	return -EINVAL;
}

static const struct dma_buf_ops udl_dmabuf_ops = {
	.attach			= udl_attach_dma_buf,
	.detach			= udl_detach_dma_buf,
	.map_dma_buf		= udl_map_dma_buf,
	.unmap_dma_buf		= udl_unmap_dma_buf,
	.map			= udl_dmabuf_kmap,
	.unmap			= udl_dmabuf_kunmap,
	.mmap			= udl_dmabuf_mmap,
	.release		= drm_gem_dmabuf_release,
};

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

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

	return drm_gem_dmabuf_export(dev, &exp_info);
}

static int udl_prime_create(struct drm_device *dev,
			    size_t size,
			    struct sg_table *sg,
			    struct udl_gem_object **obj_p)
{
	struct udl_gem_object *obj;
	int npages;

	npages = size / PAGE_SIZE;

	*obj_p = NULL;
	obj = udl_gem_alloc_object(dev, npages * PAGE_SIZE);
	if (!obj)
		return -ENOMEM;

	obj->sg = sg;
	obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
	if (obj->pages == NULL) {
		DRM_ERROR("obj pages is NULL %d\n", npages);
		return -ENOMEM;
	}

	drm_prime_sg_to_page_addr_arrays(sg, obj->pages, NULL, npages);

	*obj_p = obj;
	return 0;
}

struct drm_gem_object *udl_gem_prime_import(struct drm_device *dev,
				struct dma_buf *dma_buf)
{
	struct dma_buf_attachment *attach;
	struct sg_table *sg;
	struct udl_gem_object *uobj;
	int ret;

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

	get_dma_buf(dma_buf);

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

	ret = udl_prime_create(dev, dma_buf->size, sg, &uobj);
	if (ret)
		goto fail_unmap;

	uobj->base.import_attach = attach;
	uobj->flags = UDL_BO_WC;

	return &uobj->base;

fail_unmap:
	dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL);
fail_detach:
	dma_buf_detach(dma_buf, attach);
	dma_buf_put(dma_buf);
	put_device(dev->dev);
	return ERR_PTR(ret);
}