summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/kdebugfs.c
blob: f2d43bc7551488a61390c27cd429a9721fefbc26 (plain) (blame)
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
/*
 * Architecture specific debugfs files
 *
 * Copyright (C) 2007, Intel Corp.
 *	Huang Ying <ying.huang@intel.com>
 *
 * This file is released under the GPLv2.
 */
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/mm.h>
#include <linux/module.h>

#include <asm/setup.h>

struct dentry *arch_debugfs_dir;
EXPORT_SYMBOL(arch_debugfs_dir);

#ifdef CONFIG_DEBUG_BOOT_PARAMS
struct setup_data_node {
	u64 paddr;
	u32 type;
	u32 len;
};

static ssize_t
setup_data_read(struct file *file, char __user *user_buf, size_t count,
		loff_t *ppos)
{
	struct setup_data_node *node = file->private_data;
	unsigned long remain;
	loff_t pos = *ppos;
	struct page *pg;
	void *p;
	u64 pa;

	if (pos < 0)
		return -EINVAL;
	if (pos >= node->len)
		return 0;

	if (count > node->len - pos)
		count = node->len - pos;
	pa = node->paddr + sizeof(struct setup_data) + pos;
	pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT);
	if (PageHighMem(pg)) {
		p = ioremap_cache(pa, count);
		if (!p)
			return -ENXIO;
	} else {
		p = __va(pa);
	}

	remain = copy_to_user(user_buf, p, count);

	if (PageHighMem(pg))
		iounmap(p);

	if (remain)
		return -EFAULT;

	*ppos = pos + count;

	return count;
}

static int setup_data_open(struct inode *inode, struct file *file)
{
	file->private_data = inode->i_private;
	return 0;
}

static const struct file_operations fops_setup_data = {
	.read =		setup_data_read,
	.open =		setup_data_open,
};

static int __init
create_setup_data_node(struct dentry *parent, int no,
		       struct setup_data_node *node)
{
	struct dentry *d, *type, *data;
	char buf[16];
	int error;

	sprintf(buf, "%d", no);
	d = debugfs_create_dir(buf, parent);
	if (!d) {
		error = -ENOMEM;
		goto err_return;
	}
	type = debugfs_create_x32("type", S_IRUGO, d, &node->type);
	if (!type) {
		error = -ENOMEM;
		goto err_dir;
	}
	data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data);
	if (!data) {
		error = -ENOMEM;
		goto err_type;
	}
	return 0;

err_type:
	debugfs_remove(type);
err_dir:
	debugfs_remove(d);
err_return:
	return error;
}

static int __init create_setup_data_nodes(struct dentry *parent)
{
	struct setup_data_node *node;
	struct setup_data *data;
	int error, no = 0;
	struct dentry *d;
	struct page *pg;
	u64 pa_data;

	d = debugfs_create_dir("setup_data", parent);
	if (!d) {
		error = -ENOMEM;
		goto err_return;
	}

	pa_data = boot_params.hdr.setup_data;

	while (pa_data) {
		node = kmalloc(sizeof(*node), GFP_KERNEL);
		if (!node) {
			error = -ENOMEM;
			goto err_dir;
		}
		pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT);
		if (PageHighMem(pg)) {
			data = ioremap_cache(pa_data, sizeof(*data));
			if (!data) {
				error = -ENXIO;
				goto err_dir;
			}
		} else {
			data = __va(pa_data);
		}

		node->paddr = pa_data;
		node->type = data->type;
		node->len = data->len;
		error = create_setup_data_node(d, no, node);
		pa_data = data->next;

		if (PageHighMem(pg))
			iounmap(data);
		if (error)
			goto err_dir;
		no++;
	}
	return 0;

err_dir:
	debugfs_remove(d);
err_return:
	return error;
}

static struct debugfs_blob_wrapper boot_params_blob = {
	.data		= &boot_params,
	.size		= sizeof(boot_params),
};

static int __init boot_params_kdebugfs_init(void)
{
	struct dentry *dbp, *version, *data;
	int error;

	dbp = debugfs_create_dir("boot_params", NULL);
	if (!dbp) {
		error = -ENOMEM;
		goto err_return;
	}
	version = debugfs_create_x16("version", S_IRUGO, dbp,
				     &boot_params.hdr.version);
	if (!version) {
		error = -ENOMEM;
		goto err_dir;
	}
	data = debugfs_create_blob("data", S_IRUGO, dbp,
				   &boot_params_blob);
	if (!data) {
		error = -ENOMEM;
		goto err_version;
	}
	error = create_setup_data_nodes(dbp);
	if (error)
		goto err_data;
	return 0;

err_data:
	debugfs_remove(data);
err_version:
	debugfs_remove(version);
err_dir:
	debugfs_remove(dbp);
err_return:
	return error;
}
#endif

static int __init arch_kdebugfs_init(void)
{
	int error = 0;

	arch_debugfs_dir = debugfs_create_dir("x86", NULL);
	if (!arch_debugfs_dir)
		return -ENOMEM;

#ifdef CONFIG_DEBUG_BOOT_PARAMS
	error = boot_params_kdebugfs_init();
#endif

	return error;
}
arch_initcall(arch_kdebugfs_init);