summaryrefslogtreecommitdiff
path: root/arch/x86/platform/efi/runtime-map.c
blob: bbee682ef8cd1b19a8749cb8da73e441aad957be (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
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2013 Red Hat, Inc., Dave Young <dyoung@redhat.com>
 */

#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/efi.h>
#include <linux/slab.h>

#include <asm/efi.h>
#include <asm/setup.h>

struct efi_runtime_map_entry {
	efi_memory_desc_t md;
	struct kobject kobj;   /* kobject for each entry */
};

static struct efi_runtime_map_entry **map_entries;

struct map_attribute {
	struct attribute attr;
	ssize_t (*show)(struct efi_runtime_map_entry *entry, char *buf);
};

static inline struct map_attribute *to_map_attr(struct attribute *attr)
{
	return container_of(attr, struct map_attribute, attr);
}

static ssize_t type_show(struct efi_runtime_map_entry *entry, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "0x%x\n", entry->md.type);
}

#define EFI_RUNTIME_FIELD(var) entry->md.var

#define EFI_RUNTIME_U64_ATTR_SHOW(name) \
static ssize_t name##_show(struct efi_runtime_map_entry *entry, char *buf) \
{ \
	return snprintf(buf, PAGE_SIZE, "0x%llx\n", EFI_RUNTIME_FIELD(name)); \
}

EFI_RUNTIME_U64_ATTR_SHOW(phys_addr);
EFI_RUNTIME_U64_ATTR_SHOW(virt_addr);
EFI_RUNTIME_U64_ATTR_SHOW(num_pages);
EFI_RUNTIME_U64_ATTR_SHOW(attribute);

static inline struct efi_runtime_map_entry *to_map_entry(struct kobject *kobj)
{
	return container_of(kobj, struct efi_runtime_map_entry, kobj);
}

static ssize_t map_attr_show(struct kobject *kobj, struct attribute *attr,
			      char *buf)
{
	struct efi_runtime_map_entry *entry = to_map_entry(kobj);
	struct map_attribute *map_attr = to_map_attr(attr);

	return map_attr->show(entry, buf);
}

static struct map_attribute map_type_attr = __ATTR_RO_MODE(type, 0400);
static struct map_attribute map_phys_addr_attr = __ATTR_RO_MODE(phys_addr, 0400);
static struct map_attribute map_virt_addr_attr = __ATTR_RO_MODE(virt_addr, 0400);
static struct map_attribute map_num_pages_attr = __ATTR_RO_MODE(num_pages, 0400);
static struct map_attribute map_attribute_attr = __ATTR_RO_MODE(attribute, 0400);

/*
 * These are default attributes that are added for every memmap entry.
 */
static struct attribute *def_attrs[] = {
	&map_type_attr.attr,
	&map_phys_addr_attr.attr,
	&map_virt_addr_attr.attr,
	&map_num_pages_attr.attr,
	&map_attribute_attr.attr,
	NULL
};
ATTRIBUTE_GROUPS(def);

static const struct sysfs_ops map_attr_ops = {
	.show = map_attr_show,
};

static void map_release(struct kobject *kobj)
{
	struct efi_runtime_map_entry *entry;

	entry = to_map_entry(kobj);
	kfree(entry);
}

static struct kobj_type __refdata map_ktype = {
	.sysfs_ops	= &map_attr_ops,
	.default_groups	= def_groups,
	.release	= map_release,
};

static struct kset *map_kset;

static struct efi_runtime_map_entry *
add_sysfs_runtime_map_entry(struct kobject *kobj, int nr,
			    efi_memory_desc_t *md)
{
	int ret;
	struct efi_runtime_map_entry *entry;

	if (!map_kset) {
		map_kset = kset_create_and_add("runtime-map", NULL, kobj);
		if (!map_kset)
			return ERR_PTR(-ENOMEM);
	}

	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
	if (!entry) {
		kset_unregister(map_kset);
		map_kset = NULL;
		return ERR_PTR(-ENOMEM);
	}

	memcpy(&entry->md, md, sizeof(efi_memory_desc_t));

	kobject_init(&entry->kobj, &map_ktype);
	entry->kobj.kset = map_kset;
	ret = kobject_add(&entry->kobj, NULL, "%d", nr);
	if (ret) {
		kobject_put(&entry->kobj);
		kset_unregister(map_kset);
		map_kset = NULL;
		return ERR_PTR(ret);
	}

	return entry;
}

int efi_get_runtime_map_size(void)
{
	return efi.memmap.nr_map * efi.memmap.desc_size;
}

int efi_get_runtime_map_desc_size(void)
{
	return efi.memmap.desc_size;
}

int efi_runtime_map_copy(void *buf, size_t bufsz)
{
	size_t sz = efi_get_runtime_map_size();

	if (sz > bufsz)
		sz = bufsz;

	memcpy(buf, efi.memmap.map, sz);
	return 0;
}

static int __init efi_runtime_map_init(void)
{
	int i, j, ret = 0;
	struct efi_runtime_map_entry *entry;
	efi_memory_desc_t *md;

	if (!efi_enabled(EFI_MEMMAP) || !efi_kobj)
		return 0;

	map_entries = kcalloc(efi.memmap.nr_map, sizeof(entry), GFP_KERNEL);
	if (!map_entries) {
		ret = -ENOMEM;
		goto out;
	}

	i = 0;
	for_each_efi_memory_desc(md) {
		entry = add_sysfs_runtime_map_entry(efi_kobj, i, md);
		if (IS_ERR(entry)) {
			ret = PTR_ERR(entry);
			goto out_add_entry;
		}
		*(map_entries + i++) = entry;
	}

	return 0;
out_add_entry:
	for (j = i - 1; j >= 0; j--) {
		entry = *(map_entries + j);
		kobject_put(&entry->kobj);
	}
out:
	return ret;
}
subsys_initcall_sync(efi_runtime_map_init);