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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 int setup_data_open(struct inode *inode, struct file *file)
72{
73 file->private_data = inode->i_private;
74
75 return 0;
76}
77
78static const struct file_operations fops_setup_data = {
79 .read = setup_data_read,
80 .open = setup_data_open,
81 .llseek = default_llseek,
82};
83
84static int __init
85create_setup_data_node(struct dentry *parent, int no,
86 struct setup_data_node *node)
87{
88 struct dentry *d, *type, *data;
89 char buf[16];
90
91 sprintf(buf, "%d", no);
92 d = debugfs_create_dir(buf, parent);
93 if (!d)
94 return -ENOMEM;
95
96 type = debugfs_create_x32("type", S_IRUGO, d, &node->type);
97 if (!type)
98 goto err_dir;
99
100 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data);
101 if (!data)
102 goto err_type;
103
104 return 0;
105
106err_type:
107 debugfs_remove(type);
108err_dir:
109 debugfs_remove(d);
110 return -ENOMEM;
111}
112
113static int __init create_setup_data_nodes(struct dentry *parent)
114{
115 struct setup_data_node *node;
116 struct setup_data *data;
117 int error = -ENOMEM;
118 struct dentry *d;
119 struct page *pg;
120 u64 pa_data;
121 int no = 0;
122
123 d = debugfs_create_dir("setup_data", parent);
124 if (!d)
125 return -ENOMEM;
126
127 pa_data = boot_params.hdr.setup_data;
128
129 while (pa_data) {
130 node = kmalloc(sizeof(*node), GFP_KERNEL);
131 if (!node)
132 goto err_dir;
133
134 pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT);
135 if (PageHighMem(pg)) {
136 data = ioremap_cache(pa_data, sizeof(*data));
137 if (!data) {
138 kfree(node);
139 error = -ENXIO;
140 goto err_dir;
141 }
142 } else
143 data = __va(pa_data);
144
145 node->paddr = pa_data;
146 node->type = data->type;
147 node->len = data->len;
148 error = create_setup_data_node(d, no, node);
149 pa_data = data->next;
150
151 if (PageHighMem(pg))
152 iounmap(data);
153 if (error)
154 goto err_dir;
155 no++;
156 }
157
158 return 0;
159
160err_dir:
161 debugfs_remove(d);
162 return error;
163}
164
165static struct debugfs_blob_wrapper boot_params_blob = {
166 .data = &boot_params,
167 .size = sizeof(boot_params),
168};
169
170static int __init boot_params_kdebugfs_init(void)
171{
172 struct dentry *dbp, *version, *data;
173 int error = -ENOMEM;
174
175 dbp = debugfs_create_dir("boot_params", NULL);
176 if (!dbp)
177 return -ENOMEM;
178
179 version = debugfs_create_x16("version", S_IRUGO, dbp,
180 &boot_params.hdr.version);
181 if (!version)
182 goto err_dir;
183
184 data = debugfs_create_blob("data", S_IRUGO, dbp,
185 &boot_params_blob);
186 if (!data)
187 goto err_version;
188
189 error = create_setup_data_nodes(dbp);
190 if (error)
191 goto err_data;
192
193 return 0;
194
195err_data:
196 debugfs_remove(data);
197err_version:
198 debugfs_remove(version);
199err_dir:
200 debugfs_remove(dbp);
201 return error;
202}
203#endif
204
205static int __init arch_kdebugfs_init(void)
206{
207 int error = 0;
208
209 arch_debugfs_dir = debugfs_create_dir("x86", NULL);
210 if (!arch_debugfs_dir)
211 return -ENOMEM;
212
213#ifdef CONFIG_DEBUG_BOOT_PARAMS
214 error = boot_params_kdebugfs_init();
215#endif
216
217 return error;
218}
219arch_initcall(arch_kdebugfs_init);
220
