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
|
/*
* This file is part of the coreboot project.
*
* Copyright 2015 Google Inc.
*
* 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; version 2 of the License.
*
* 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, write to the Free Software
* Foundation, Inc.
*/
#include <region.h>
#include <string.h>
static inline size_t region_offset(const struct region *r)
{
return r->offset;
}
static inline size_t region_end(const struct region *r)
{
return region_sz(r) + region_offset(r);
}
static int is_subregion(const struct region *p, const struct region *c)
{
if (region_offset(c) < region_offset(p))
return 0;
if (region_sz(c) > region_sz(p))
return 0;
if (region_end(c) > region_end(p))
return 0;
return 1;
}
static int normalize_and_ok(const struct region *outer, struct region *inner)
{
inner->offset += region_offset(outer);
return is_subregion(outer, inner);
}
static const struct region_device *rdev_root(const struct region_device *rdev)
{
if (rdev->root == NULL)
return rdev;
return rdev->root;
}
void *rdev_mmap(const struct region_device *rd, size_t offset, size_t size)
{
const struct region_device *rdev;
struct region req = {
.offset = offset,
.size = size,
};
if (!normalize_and_ok(&rd->region, &req))
return NULL;
rdev = rdev_root(rd);
return rdev->ops->mmap(rdev, req.offset, req.size);
}
int rdev_munmap(const struct region_device *rd, void *mapping)
{
const struct region_device *rdev;
rdev = rdev_root(rd);
return rdev->ops->munmap(rdev, mapping);
}
ssize_t rdev_readat(const struct region_device *rd, void *b, size_t offset,
size_t size)
{
const struct region_device *rdev;
struct region req = {
.offset = offset,
.size = size,
};
if (!normalize_and_ok(&rd->region, &req))
return -1;
rdev = rdev_root(rd);
return rdev->ops->readat(rdev, b, req.offset, req.size);
}
int rdev_chain(struct region_device *child, const struct region_device *parent,
size_t offset, size_t size)
{
struct region req = {
.offset = offset,
.size = size,
};
if (!normalize_and_ok(&parent->region, &req))
return -1;
/* Keep track of root region device. Note the offsets are relative
* to the root device. */
child->root = rdev_root(parent);
child->ops = NULL;
child->region.offset = req.offset;
child->region.size = req.size;
return 0;
}
void mem_region_device_init(struct mem_region_device *mdev, void *base,
size_t size)
{
memset(mdev, 0, sizeof(*mdev));
mdev->base = base;
mdev->rdev.ops = &mem_rdev_ops;
mdev->rdev.region.size = size;
}
static void *mdev_mmap(const struct region_device *rd, size_t offset,
size_t size)
{
const struct mem_region_device *mdev;
mdev = container_of(rd, typeof(*mdev), rdev);
return &mdev->base[offset];
}
static int mdev_munmap(const struct region_device *rd, void *mapping)
{
return 0;
}
static ssize_t mdev_readat(const struct region_device *rd, void *b,
size_t offset, size_t size)
{
const struct mem_region_device *mdev;
mdev = container_of(rd, typeof(*mdev), rdev);
memcpy(b, &mdev->base[offset], size);
return size;
}
const struct region_device_ops mem_rdev_ops = {
.mmap = mdev_mmap,
.munmap = mdev_munmap,
.readat = mdev_readat,
};
|
