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9#include <linux/debugfs.h>
10#include <linux/uaccess.h>
11#include <linux/export.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 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 p = memremap(pa, count, MEMREMAP_WB);
50 if (!p)
51 return -ENOMEM;
52
53 remain = copy_to_user(user_buf, p, count);
54
55 memunmap(p);
56
57 if (remain)
58 return -EFAULT;
59
60 *ppos = pos + count;
61
62 return count;
63}
64
65static const struct file_operations fops_setup_data = {
66 .read = setup_data_read,
67 .open = simple_open,
68 .llseek = default_llseek,
69};
70
71static int __init
72create_setup_data_node(struct dentry *parent, int no,
73 struct setup_data_node *node)
74{
75 struct dentry *d, *type, *data;
76 char buf[16];
77
78 sprintf(buf, "%d", no);
79 d = debugfs_create_dir(buf, parent);
80 if (!d)
81 return -ENOMEM;
82
83 type = debugfs_create_x32("type", S_IRUGO, d, &node->type);
84 if (!type)
85 goto err_dir;
86
87 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data);
88 if (!data)
89 goto err_type;
90
91 return 0;
92
93err_type:
94 debugfs_remove(type);
95err_dir:
96 debugfs_remove(d);
97 return -ENOMEM;
98}
99
100static int __init create_setup_data_nodes(struct dentry *parent)
101{
102 struct setup_data_node *node;
103 struct setup_data *data;
104 int error;
105 struct dentry *d;
106 u64 pa_data;
107 int no = 0;
108
109 d = debugfs_create_dir("setup_data", parent);
110 if (!d)
111 return -ENOMEM;
112
113 pa_data = boot_params.hdr.setup_data;
114
115 while (pa_data) {
116 node = kmalloc(sizeof(*node), GFP_KERNEL);
117 if (!node) {
118 error = -ENOMEM;
119 goto err_dir;
120 }
121
122 data = memremap(pa_data, sizeof(*data), MEMREMAP_WB);
123 if (!data) {
124 kfree(node);
125 error = -ENOMEM;
126 goto err_dir;
127 }
128
129 node->paddr = pa_data;
130 node->type = data->type;
131 node->len = data->len;
132 error = create_setup_data_node(d, no, node);
133 pa_data = data->next;
134
135 memunmap(data);
136 if (error)
137 goto err_dir;
138 no++;
139 }
140
141 return 0;
142
143err_dir:
144 debugfs_remove(d);
145 return error;
146}
147
148static struct debugfs_blob_wrapper boot_params_blob = {
149 .data = &boot_params,
150 .size = sizeof(boot_params),
151};
152
153static int __init boot_params_kdebugfs_init(void)
154{
155 struct dentry *dbp, *version, *data;
156 int error = -ENOMEM;
157
158 dbp = debugfs_create_dir("boot_params", arch_debugfs_dir);
159 if (!dbp)
160 return -ENOMEM;
161
162 version = debugfs_create_x16("version", S_IRUGO, dbp,
163 &boot_params.hdr.version);
164 if (!version)
165 goto err_dir;
166
167 data = debugfs_create_blob("data", S_IRUGO, dbp,
168 &boot_params_blob);
169 if (!data)
170 goto err_version;
171
172 error = create_setup_data_nodes(dbp);
173 if (error)
174 goto err_data;
175
176 return 0;
177
178err_data:
179 debugfs_remove(data);
180err_version:
181 debugfs_remove(version);
182err_dir:
183 debugfs_remove(dbp);
184 return error;
185}
186#endif
187
188static int __init arch_kdebugfs_init(void)
189{
190 int error = 0;
191
192 arch_debugfs_dir = debugfs_create_dir("x86", NULL);
193 if (!arch_debugfs_dir)
194 return -ENOMEM;
195
196#ifdef CONFIG_DEBUG_BOOT_PARAMS
197 error = boot_params_kdebugfs_init();
198#endif
199
200 return error;
201}
202arch_initcall(arch_kdebugfs_init);
203
