Merge branch 'linus' into tracing/hw-breakpoints
[linux-2.6.git] / arch / x86 / kernel / kdebugfs.c
1 /*
2  * Architecture specific debugfs files
3  *
4  * Copyright (C) 2007, Intel Corp.
5  *      Huang Ying <ying.huang@intel.com>
6  *
7  * This file is released under the GPLv2.
8  */
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
19 struct dentry *arch_debugfs_dir;
20 EXPORT_SYMBOL(arch_debugfs_dir);
21
22 #ifdef CONFIG_DEBUG_BOOT_PARAMS
23 struct setup_data_node {
24         u64 paddr;
25         u32 type;
26         u32 len;
27 };
28
29 static 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
70 static int setup_data_open(struct inode *inode, struct file *file)
71 {
72         file->private_data = inode->i_private;
73
74         return 0;
75 }
76
77 static const struct file_operations fops_setup_data = {
78         .read           = setup_data_read,
79         .open           = setup_data_open,
80 };
81
82 static int __init
83 create_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
104 err_type:
105         debugfs_remove(type);
106 err_dir:
107         debugfs_remove(d);
108         return -ENOMEM;
109 }
110
111 static 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
158 err_dir:
159         debugfs_remove(d);
160         return error;
161 }
162
163 static struct debugfs_blob_wrapper boot_params_blob = {
164         .data           = &boot_params,
165         .size           = sizeof(boot_params),
166 };
167
168 static 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
193 err_data:
194         debugfs_remove(data);
195 err_version:
196         debugfs_remove(version);
197 err_dir:
198         debugfs_remove(dbp);
199         return error;
200 }
201 #endif /* CONFIG_DEBUG_BOOT_PARAMS */
202
203 static 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 }
217 arch_initcall(arch_kdebugfs_init);