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6#include <linux/errno.h>
7#include <linux/init.h>
8#include <linux/time.h>
9#include <linux/proc_fs.h>
10#include <linux/seq_file.h>
11#include <linux/printk.h>
12#include <linux/stat.h>
13#include <linux/string.h>
14#include <linux/of.h>
15#include <linux/export.h>
16#include <linux/slab.h>
17#include <asm/prom.h>
18#include <asm/uaccess.h>
19#include "internal.h"
20
21static inline void set_node_proc_entry(struct device_node *np,
22 struct proc_dir_entry *de)
23{
24#ifdef HAVE_ARCH_DEVTREE_FIXUPS
25 np->pde = de;
26#endif
27}
28
29static struct proc_dir_entry *proc_device_tree;
30
31
32
33
34static int property_proc_show(struct seq_file *m, void *v)
35{
36 struct property *pp = m->private;
37
38 seq_write(m, pp->value, pp->length);
39 return 0;
40}
41
42static int property_proc_open(struct inode *inode, struct file *file)
43{
44 return single_open(file, property_proc_show, __PDE_DATA(inode));
45}
46
47static const struct file_operations property_proc_fops = {
48 .owner = THIS_MODULE,
49 .open = property_proc_open,
50 .read = seq_read,
51 .llseek = seq_lseek,
52 .release = single_release,
53};
54
55
56
57
58
59
60
61
62
63static struct proc_dir_entry *
64__proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp,
65 const char *name)
66{
67 struct proc_dir_entry *ent;
68
69
70
71
72
73 ent = proc_create_data(name,
74 strncmp(name, "security-", 9) ? S_IRUGO : S_IRUSR,
75 de, &property_proc_fops, pp);
76 if (ent == NULL)
77 return NULL;
78
79 if (!strncmp(name, "security-", 9))
80 ent->size = 0;
81 else
82 ent->size = pp->length;
83
84 return ent;
85}
86
87
88void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop)
89{
90 __proc_device_tree_add_prop(pde, prop, prop->name);
91}
92
93void proc_device_tree_remove_prop(struct proc_dir_entry *pde,
94 struct property *prop)
95{
96 remove_proc_entry(prop->name, pde);
97}
98
99void proc_device_tree_update_prop(struct proc_dir_entry *pde,
100 struct property *newprop,
101 struct property *oldprop)
102{
103 struct proc_dir_entry *ent;
104
105 if (!oldprop) {
106 proc_device_tree_add_prop(pde, newprop);
107 return;
108 }
109
110 for (ent = pde->subdir; ent != NULL; ent = ent->next)
111 if (ent->data == oldprop)
112 break;
113 if (ent == NULL) {
114 pr_warn("device-tree: property \"%s\" does not exist\n",
115 oldprop->name);
116 } else {
117 ent->data = newprop;
118 ent->size = newprop->length;
119 }
120}
121
122
123
124
125
126
127
128static int duplicate_name(struct proc_dir_entry *de, const char *name)
129{
130 struct proc_dir_entry *ent;
131 int found = 0;
132
133 spin_lock(&proc_subdir_lock);
134
135 for (ent = de->subdir; ent != NULL; ent = ent->next) {
136 if (strcmp(ent->name, name) == 0) {
137 found = 1;
138 break;
139 }
140 }
141
142 spin_unlock(&proc_subdir_lock);
143
144 return found;
145}
146
147static const char *fixup_name(struct device_node *np, struct proc_dir_entry *de,
148 const char *name)
149{
150 char *fixed_name;
151 int fixup_len = strlen(name) + 2 + 1;
152 int i = 1, size;
153
154realloc:
155 fixed_name = kmalloc(fixup_len, GFP_KERNEL);
156 if (fixed_name == NULL) {
157 pr_err("device-tree: Out of memory trying to fixup "
158 "name \"%s\"\n", name);
159 return name;
160 }
161
162retry:
163 size = snprintf(fixed_name, fixup_len, "%s#%d", name, i);
164 size++;
165
166 if (size > fixup_len) {
167
168 kfree(fixed_name);
169 fixup_len = size;
170 goto realloc;
171 }
172
173 if (duplicate_name(de, fixed_name)) {
174
175 i++;
176 goto retry;
177 }
178
179 pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n",
180 np->full_name, fixed_name);
181
182 return fixed_name;
183}
184
185
186
187
188void proc_device_tree_add_node(struct device_node *np,
189 struct proc_dir_entry *de)
190{
191 struct property *pp;
192 struct proc_dir_entry *ent;
193 struct device_node *child;
194 const char *p;
195
196 set_node_proc_entry(np, de);
197 for (child = NULL; (child = of_get_next_child(np, child));) {
198
199 p = kbasename(child->full_name);
200
201 if (duplicate_name(de, p))
202 p = fixup_name(np, de, p);
203
204 ent = proc_mkdir(p, de);
205 if (ent == NULL)
206 break;
207 proc_device_tree_add_node(child, ent);
208 }
209 of_node_put(child);
210
211 for (pp = np->properties; pp != NULL; pp = pp->next) {
212 p = pp->name;
213
214 if (strchr(p, '/'))
215 continue;
216
217 if (duplicate_name(de, p))
218 p = fixup_name(np, de, p);
219
220 ent = __proc_device_tree_add_prop(de, pp, p);
221 if (ent == NULL)
222 break;
223 }
224}
225
226
227
228
229void __init proc_device_tree_init(void)
230{
231 struct device_node *root;
232
233 proc_device_tree = proc_mkdir("device-tree", NULL);
234 if (proc_device_tree == NULL)
235 return;
236 root = of_find_node_by_path("/");
237 if (root == NULL) {
238 pr_debug("/proc/device-tree: can't find root\n");
239 return;
240 }
241 proc_device_tree_add_node(root, proc_device_tree);
242 of_node_put(root);
243}
244