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9#include <linux/debugfs.h>
10#include <linux/uaccess.h>
11#include <linux/module.h>
12#include <linux/init.h>
13#include <linux/stat.h>
14#include <linux/io.h>
15#include <linux/mm.h>
16
17#include <asm/setup.h>
18
19struct dentry *arch_debugfs_dir;
20EXPORT_SYMBOL(arch_debugfs_dir);
21
22#ifdef CONFIG_DEBUG_BOOT_PARAMS
23struct setup_data_node {
24 u64 paddr;
25 u32 type;
26 u32 len;
27};
28
29static ssize_t setup_data_read(struct file *file, char __user *user_buf,
30 size_t count, loff_t *ppos)
31{
32 struct setup_data_node *node = file->private_data;
33 unsigned long remain;
34 loff_t pos = *ppos;
35 struct page *pg;
36 void *p;
37 u64 pa;
38
39 if (pos < 0)
40 return -EINVAL;
41
42 if (pos >= node->len)
43 return 0;
44
45 if (count > node->len - pos)
46 count = node->len - pos;
47
48 pa = node->paddr + sizeof(struct setup_data) + pos;
49 pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT);
50 if (PageHighMem(pg)) {
51 p = ioremap_cache(pa, count);
52 if (!p)
53 return -ENXIO;
54 } else
55 p = __va(pa);
56
57 remain = copy_to_user(user_buf, p, count);
58
59 if (PageHighMem(pg))
60 iounmap(p);
61
62 if (remain)
63 return -EFAULT;
64
65 *ppos = pos + count;
66
67 return count;
68}
69
70static int setup_data_open(struct inode *inode, struct file *file)
71{
72 file->private_data = inode->i_private;
73
74 return 0;
75}
76
77static const struct file_operations fops_setup_data = {
78 .read = setup_data_read,
79 .open = setup_data_open,
80};
81
82static int __init
83create_setup_data_node(struct dentry *parent, int no,
84 struct setup_data_node *node)
85{
86 struct dentry *d, *type, *data;
87 char buf[16];
88
89 sprintf(buf, "%d", no);
90 d = debugfs_create_dir(buf, parent);
91 if (!d)
92 return -ENOMEM;
93
94 type = debugfs_create_x32("type", S_IRUGO, d, &node->type);
95 if (!type)
96 goto err_dir;
97
98 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data);
99 if (!data)
100 goto err_type;
101
102 return 0;
103
104err_type:
105 debugfs_remove(type);
106err_dir:
107 debugfs_remove(d);
108 return -ENOMEM;
109}
110
111static int __init create_setup_data_nodes(struct dentry *parent)
112{
113 struct setup_data_node *node;
114 struct setup_data *data;
115 int error = -ENOMEM;
116 struct dentry *d;
117 struct page *pg;
118 u64 pa_data;
119 int no = 0;
120
121 d = debugfs_create_dir("setup_data", parent);
122 if (!d)
123 return -ENOMEM;
124
125 pa_data = boot_params.hdr.setup_data;
126
127 while (pa_data) {
128 node = kmalloc(sizeof(*node), GFP_KERNEL);
129 if (!node)
130 goto err_dir;
131
132 pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT);
133 if (PageHighMem(pg)) {
134 data = ioremap_cache(pa_data, sizeof(*data));
135 if (!data) {
136 kfree(node);
137 error = -ENXIO;
138 goto err_dir;
139 }
140 } else
141 data = __va(pa_data);
142
143 node->paddr = pa_data;
144 node->type = data->type;
145 node->len = data->len;
146 error = create_setup_data_node(d, no, node);
147 pa_data = data->next;
148
149 if (PageHighMem(pg))
150 iounmap(data);
151 if (error)
152 goto err_dir;
153 no++;
154 }
155
156 return 0;
157
158err_dir:
159 debugfs_remove(d);
160 return error;
161}
162
163static struct debugfs_blob_wrapper boot_params_blob = {
164 .data = &boot_params,
165 .size = sizeof(boot_params),
166};
167
168static int __init boot_params_kdebugfs_init(void)
169{
170 struct dentry *dbp, *version, *data;
171 int error = -ENOMEM;
172
173 dbp = debugfs_create_dir("boot_params", NULL);
174 if (!dbp)
175 return -ENOMEM;
176
177 version = debugfs_create_x16("version", S_IRUGO, dbp,
178 &boot_params.hdr.version);
179 if (!version)
180 goto err_dir;
181
182 data = debugfs_create_blob("data", S_IRUGO, dbp,
183 &boot_params_blob);
184 if (!data)
185 goto err_version;
186
187 error = create_setup_data_nodes(dbp);
188 if (error)
189 goto err_data;
190
191 return 0;
192
193err_data:
194 debugfs_remove(data);
195err_version:
196 debugfs_remove(version);
197err_dir:
198 debugfs_remove(dbp);
199 return error;
200}
201#endif
202
203static int __init arch_kdebugfs_init(void)
204{
205 int error = 0;
206
207 arch_debugfs_dir = debugfs_create_dir("x86", NULL);
208 if (!arch_debugfs_dir)
209 return -ENOMEM;
210
211#ifdef CONFIG_DEBUG_BOOT_PARAMS
212 error = boot_params_kdebugfs_init();
213#endif
214
215 return error;
216}
217arch_initcall(arch_kdebugfs_init);
218
