summaryrefslogtreecommitdiff
path: root/drivers/media/platform/nvidia/tegra-vde/dmabuf-cache.c
blob: 1c5b94989aec071063e9a1a7721c15ce6100bde2 (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
// SPDX-License-Identifier: GPL-2.0+
/*
 * NVIDIA Tegra Video decoder driver
 *
 * Copyright (C) 2016-2019 GRATE-DRIVER project
 */

#include <linux/dma-buf.h>
#include <linux/iova.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/module.h>

#include "vde.h"

MODULE_IMPORT_NS(DMA_BUF);

struct tegra_vde_cache_entry {
	enum dma_data_direction dma_dir;
	struct dma_buf_attachment *a;
	struct delayed_work dwork;
	struct tegra_vde *vde;
	struct list_head list;
	struct sg_table *sgt;
	struct iova *iova;
	unsigned int refcnt;
};

static void tegra_vde_release_entry(struct tegra_vde_cache_entry *entry)
{
	struct dma_buf *dmabuf = entry->a->dmabuf;

	WARN_ON_ONCE(entry->refcnt);

	if (entry->vde->domain)
		tegra_vde_iommu_unmap(entry->vde, entry->iova);

	dma_buf_unmap_attachment_unlocked(entry->a, entry->sgt, entry->dma_dir);
	dma_buf_detach(dmabuf, entry->a);
	dma_buf_put(dmabuf);

	list_del(&entry->list);
	kfree(entry);
}

static void tegra_vde_delayed_unmap(struct work_struct *work)
{
	struct tegra_vde_cache_entry *entry;
	struct tegra_vde *vde;

	entry = container_of(work, struct tegra_vde_cache_entry,
			     dwork.work);
	vde = entry->vde;

	mutex_lock(&vde->map_lock);
	tegra_vde_release_entry(entry);
	mutex_unlock(&vde->map_lock);
}

int tegra_vde_dmabuf_cache_map(struct tegra_vde *vde,
			       struct dma_buf *dmabuf,
			       enum dma_data_direction dma_dir,
			       struct dma_buf_attachment **ap,
			       dma_addr_t *addrp)
{
	struct dma_buf_attachment *attachment;
	struct tegra_vde_cache_entry *entry;
	struct device *dev = vde->dev;
	struct sg_table *sgt;
	struct iova *iova;
	int err;

	mutex_lock(&vde->map_lock);

	list_for_each_entry(entry, &vde->map_list, list) {
		if (entry->a->dmabuf != dmabuf)
			continue;

		if (!cancel_delayed_work(&entry->dwork))
			continue;

		if (entry->dma_dir != dma_dir)
			entry->dma_dir = DMA_BIDIRECTIONAL;

		dma_buf_put(dmabuf);

		if (vde->domain)
			*addrp = iova_dma_addr(&vde->iova, entry->iova);
		else
			*addrp = sg_dma_address(entry->sgt->sgl);

		goto ref;
	}

	attachment = dma_buf_attach(dmabuf, dev);
	if (IS_ERR(attachment)) {
		dev_err(dev, "Failed to attach dmabuf\n");
		err = PTR_ERR(attachment);
		goto err_unlock;
	}

	sgt = dma_buf_map_attachment_unlocked(attachment, dma_dir);
	if (IS_ERR(sgt)) {
		dev_err(dev, "Failed to get dmabufs sg_table\n");
		err = PTR_ERR(sgt);
		goto err_detach;
	}

	if (!vde->domain && sgt->nents > 1) {
		dev_err(dev, "Sparse DMA region is unsupported, please enable IOMMU\n");
		err = -EINVAL;
		goto err_unmap;
	}

	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
	if (!entry) {
		err = -ENOMEM;
		goto err_unmap;
	}

	if (vde->domain) {
		err = tegra_vde_iommu_map(vde, sgt, &iova, dmabuf->size);
		if (err)
			goto err_free;

		*addrp = iova_dma_addr(&vde->iova, iova);
	} else {
		*addrp = sg_dma_address(sgt->sgl);
		iova = NULL;
	}

	INIT_DELAYED_WORK(&entry->dwork, tegra_vde_delayed_unmap);
	list_add(&entry->list, &vde->map_list);

	entry->dma_dir = dma_dir;
	entry->iova = iova;
	entry->vde = vde;
	entry->sgt = sgt;
	entry->a = attachment;
ref:
	entry->refcnt++;

	*ap = entry->a;

	mutex_unlock(&vde->map_lock);

	return 0;

err_free:
	kfree(entry);
err_unmap:
	dma_buf_unmap_attachment_unlocked(attachment, sgt, dma_dir);
err_detach:
	dma_buf_detach(dmabuf, attachment);
err_unlock:
	mutex_unlock(&vde->map_lock);

	return err;
}

void tegra_vde_dmabuf_cache_unmap(struct tegra_vde *vde,
				  struct dma_buf_attachment *a,
				  bool release)
{
	struct tegra_vde_cache_entry *entry;

	mutex_lock(&vde->map_lock);

	list_for_each_entry(entry, &vde->map_list, list) {
		if (entry->a != a)
			continue;

		WARN_ON_ONCE(!entry->refcnt);

		if (--entry->refcnt == 0) {
			if (release)
				tegra_vde_release_entry(entry);
			else
				schedule_delayed_work(&entry->dwork, 5 * HZ);
		}
		break;
	}

	mutex_unlock(&vde->map_lock);
}

void tegra_vde_dmabuf_cache_unmap_sync(struct tegra_vde *vde)
{
	struct tegra_vde_cache_entry *entry, *tmp;

	mutex_lock(&vde->map_lock);

	list_for_each_entry_safe(entry, tmp, &vde->map_list, list) {
		if (entry->refcnt)
			continue;

		if (!cancel_delayed_work(&entry->dwork))
			continue;

		tegra_vde_release_entry(entry);
	}

	mutex_unlock(&vde->map_lock);
}

void tegra_vde_dmabuf_cache_unmap_all(struct tegra_vde *vde)
{
	struct tegra_vde_cache_entry *entry, *tmp;

	mutex_lock(&vde->map_lock);

	while (!list_empty(&vde->map_list)) {
		list_for_each_entry_safe(entry, tmp, &vde->map_list, list) {
			if (!cancel_delayed_work(&entry->dwork))
				continue;

			tegra_vde_release_entry(entry);
		}

		mutex_unlock(&vde->map_lock);
		schedule();
		mutex_lock(&vde->map_lock);
	}

	mutex_unlock(&vde->map_lock);
}