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9#include <linux/debugfs.h>
10#include <linux/uaccess.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/init.h>
14#include <linux/stat.h>
15#include <linux/io.h>
16#include <linux/mm.h>
17
18#include <asm/setup.h>
19
20struct dentry *arch_debugfs_dir;
21EXPORT_SYMBOL(arch_debugfs_dir);
22
23#ifdef CONFIG_DEBUG_BOOT_PARAMS
24struct setup_data_node {
25 u64 paddr;
26 u32 type;
27 u32 len;
28};
29
30static ssize_t setup_data_read(struct file *file, char __user *user_buf,
31 size_t count, loff_t *ppos)
32{
33 struct setup_data_node *node = file->private_data;
34 unsigned long remain;
35 loff_t pos = *ppos;
36 struct page *pg;
37 void *p;
38 u64 pa;
39
40 if (pos < 0)
41 return -EINVAL;
42
43 if (pos >= node->len)
44 return 0;
45
46 if (count > node->len - pos)
47 count = node->len - pos;
48
49 pa = node->paddr + sizeof(struct setup_data) + pos;
50 pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT);
51 if (PageHighMem(pg)) {
52 p = ioremap_cache(pa, count);
53 if (!p)
54 return -ENXIO;
55 } else
56 p = __va(pa);
57
58 remain = copy_to_user(user_buf, p, count);
59
60 if (PageHighMem(pg))
61 iounmap(p);
62
63 if (remain)
64 return -EFAULT;
65
66 *ppos = pos + count;
67
68 return count;
69}
70
71static const struct file_operations fops_setup_data = {
72 .read = setup_data_read,
73 .open = simple_open,
74 .llseek = default_llseek,
75};
76
77static int __init
78create_setup_data_node(struct dentry *parent, int no,
79 struct setup_data_node *node)
80{
81 struct dentry *d, *type, *data;
82 char buf[16];
83
84 sprintf(buf, "%d", no);
85 d = debugfs_create_dir(buf, parent);
86 if (!d)
87 return -ENOMEM;
88
89 type = debugfs_create_x32("type", S_IRUGO, d, &node->type);
90 if (!type)
91 goto err_dir;
92
93 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data);
94 if (!data)
95 goto err_type;
96
97 return 0;
98
99err_type:
100 debugfs_remove(type);
101err_dir:
102 debugfs_remove(d);
103 return -ENOMEM;
104}
105
106static int __init create_setup_data_nodes(struct dentry *parent)
107{
108 struct setup_data_node *node;
109 struct setup_data *data;
110 int error = -ENOMEM;
111 struct dentry *d;
112 struct page *pg;
113 u64 pa_data;
114 int no = 0;
115
116 d = debugfs_create_dir("setup_data", parent);
117 if (!d)
118 return -ENOMEM;
119
120 pa_data = boot_params.hdr.setup_data;
121
122 while (pa_data) {
123 node = kmalloc(sizeof(*node), GFP_KERNEL);
124 if (!node)
125 goto err_dir;
126
127 pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT);
128 if (PageHighMem(pg)) {
129 data = ioremap_cache(pa_data, sizeof(*data));
130 if (!data) {
131 kfree(node);
132 error = -ENXIO;
133 goto err_dir;
134 }
135 } else
136 data = __va(pa_data);
137
138 node->paddr = pa_data;
139 node->type = data->type;
140 node->len = data->len;
141 error = create_setup_data_node(d, no, node);
142 pa_data = data->next;
143
144 if (PageHighMem(pg))
145 iounmap(data);
146 if (error)
147 goto err_dir;
148 no++;
149 }
150
151 return 0;
152
153err_dir:
154 debugfs_remove(d);
155 return error;
156}
157
158static struct debugfs_blob_wrapper boot_params_blob = {
159 .data = &boot_params,
160 .size = sizeof(boot_params),
161};
162
163static int __init boot_params_kdebugfs_init(void)
164{
165 struct dentry *dbp, *version, *data;
166 int error = -ENOMEM;
167
168 dbp = debugfs_create_dir("boot_params", NULL);
169 if (!dbp)
170 return -ENOMEM;
171
172 version = debugfs_create_x16("version", S_IRUGO, dbp,
173 &boot_params.hdr.version);
174 if (!version)
175 goto err_dir;
176
177 data = debugfs_create_blob("data", S_IRUGO, dbp,
178 &boot_params_blob);
179 if (!data)
180 goto err_version;
181
182 error = create_setup_data_nodes(dbp);
183 if (error)
184 goto err_data;
185
186 return 0;
187
188err_data:
189 debugfs_remove(data);
190err_version:
191 debugfs_remove(version);
192err_dir:
193 debugfs_remove(dbp);
194 return error;
195}
196#endif
197
198static int __init arch_kdebugfs_init(void)
199{
200 int error = 0;
201
202 arch_debugfs_dir = debugfs_create_dir("x86", NULL);
203 if (!arch_debugfs_dir)
204 return -ENOMEM;
205
206#ifdef CONFIG_DEBUG_BOOT_PARAMS
207 error = boot_params_kdebugfs_init();
208#endif
209
210 return error;
211}
212arch_initcall(arch_kdebugfs_init);
213
