Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * proc_devtree.c - handles /proc/device-tree | |
3 | * | |
4 | * Copyright 1997 Paul Mackerras | |
5 | */ | |
6 | #include <linux/errno.h> | |
1e0edd3f | 7 | #include <linux/init.h> |
1da177e4 LT |
8 | #include <linux/time.h> |
9 | #include <linux/proc_fs.h> | |
e22f6283 | 10 | #include <linux/seq_file.h> |
1da177e4 LT |
11 | #include <linux/stat.h> |
12 | #include <linux/string.h> | |
13 | #include <asm/prom.h> | |
14 | #include <asm/uaccess.h> | |
3174c21b | 15 | #include "internal.h" |
1da177e4 LT |
16 | |
17 | #ifndef HAVE_ARCH_DEVTREE_FIXUPS | |
5f64f739 BH |
18 | static inline void set_node_proc_entry(struct device_node *np, |
19 | struct proc_dir_entry *de) | |
1da177e4 LT |
20 | { |
21 | } | |
22 | #endif | |
23 | ||
24 | static struct proc_dir_entry *proc_device_tree; | |
25 | ||
26 | /* | |
27 | * Supply data on a read from /proc/device-tree/node/property. | |
28 | */ | |
e22f6283 | 29 | static int property_proc_show(struct seq_file *m, void *v) |
1da177e4 | 30 | { |
e22f6283 | 31 | struct property *pp = m->private; |
1da177e4 | 32 | |
e22f6283 AD |
33 | seq_write(m, pp->value, pp->length); |
34 | return 0; | |
1da177e4 LT |
35 | } |
36 | ||
e22f6283 AD |
37 | static int property_proc_open(struct inode *inode, struct file *file) |
38 | { | |
39 | return single_open(file, property_proc_show, PDE(inode)->data); | |
40 | } | |
41 | ||
42 | static const struct file_operations property_proc_fops = { | |
43 | .owner = THIS_MODULE, | |
44 | .open = property_proc_open, | |
45 | .read = seq_read, | |
46 | .llseek = seq_lseek, | |
47 | .release = single_release, | |
48 | }; | |
49 | ||
1da177e4 LT |
50 | /* |
51 | * For a node with a name like "gc@10", we make symlinks called "gc" | |
52 | * and "@10" to it. | |
53 | */ | |
54 | ||
183d0202 BH |
55 | /* |
56 | * Add a property to a node | |
57 | */ | |
58 | static struct proc_dir_entry * | |
5149fa47 ME |
59 | __proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp, |
60 | const char *name) | |
183d0202 BH |
61 | { |
62 | struct proc_dir_entry *ent; | |
63 | ||
64 | /* | |
65 | * Unfortunately proc_register puts each new entry | |
66 | * at the beginning of the list. So we rearrange them. | |
67 | */ | |
e22f6283 AD |
68 | ent = proc_create_data(name, |
69 | strncmp(name, "security-", 9) ? S_IRUGO : S_IRUSR, | |
70 | de, &property_proc_fops, pp); | |
183d0202 BH |
71 | if (ent == NULL) |
72 | return NULL; | |
73 | ||
5149fa47 | 74 | if (!strncmp(name, "security-", 9)) |
183d0202 BH |
75 | ent->size = 0; /* don't leak number of password chars */ |
76 | else | |
77 | ent->size = pp->length; | |
78 | ||
79 | return ent; | |
80 | } | |
81 | ||
82 | ||
83 | void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop) | |
84 | { | |
5149fa47 | 85 | __proc_device_tree_add_prop(pde, prop, prop->name); |
183d0202 BH |
86 | } |
87 | ||
898b5395 DB |
88 | void proc_device_tree_remove_prop(struct proc_dir_entry *pde, |
89 | struct property *prop) | |
90 | { | |
91 | remove_proc_entry(prop->name, pde); | |
92 | } | |
93 | ||
94 | void proc_device_tree_update_prop(struct proc_dir_entry *pde, | |
95 | struct property *newprop, | |
96 | struct property *oldprop) | |
97 | { | |
98 | struct proc_dir_entry *ent; | |
99 | ||
100 | for (ent = pde->subdir; ent != NULL; ent = ent->next) | |
101 | if (ent->data == oldprop) | |
102 | break; | |
103 | if (ent == NULL) { | |
104 | printk(KERN_WARNING "device-tree: property \"%s\" " | |
105 | " does not exist\n", oldprop->name); | |
106 | } else { | |
107 | ent->data = newprop; | |
108 | ent->size = newprop->length; | |
109 | } | |
110 | } | |
111 | ||
5149fa47 ME |
112 | /* |
113 | * Various dodgy firmware might give us nodes and/or properties with | |
114 | * conflicting names. That's generally ok, except for exporting via /proc, | |
115 | * so munge names here to ensure they're unique. | |
116 | */ | |
117 | ||
118 | static int duplicate_name(struct proc_dir_entry *de, const char *name) | |
119 | { | |
120 | struct proc_dir_entry *ent; | |
121 | int found = 0; | |
122 | ||
123 | spin_lock(&proc_subdir_lock); | |
124 | ||
125 | for (ent = de->subdir; ent != NULL; ent = ent->next) { | |
126 | if (strcmp(ent->name, name) == 0) { | |
127 | found = 1; | |
128 | break; | |
129 | } | |
130 | } | |
131 | ||
132 | spin_unlock(&proc_subdir_lock); | |
133 | ||
134 | return found; | |
135 | } | |
136 | ||
137 | static const char *fixup_name(struct device_node *np, struct proc_dir_entry *de, | |
138 | const char *name) | |
139 | { | |
140 | char *fixed_name; | |
141 | int fixup_len = strlen(name) + 2 + 1; /* name + #x + \0 */ | |
142 | int i = 1, size; | |
143 | ||
144 | realloc: | |
145 | fixed_name = kmalloc(fixup_len, GFP_KERNEL); | |
146 | if (fixed_name == NULL) { | |
147 | printk(KERN_ERR "device-tree: Out of memory trying to fixup " | |
148 | "name \"%s\"\n", name); | |
149 | return name; | |
150 | } | |
151 | ||
152 | retry: | |
153 | size = snprintf(fixed_name, fixup_len, "%s#%d", name, i); | |
154 | size++; /* account for NULL */ | |
155 | ||
156 | if (size > fixup_len) { | |
157 | /* We ran out of space, free and reallocate. */ | |
158 | kfree(fixed_name); | |
159 | fixup_len = size; | |
160 | goto realloc; | |
161 | } | |
162 | ||
163 | if (duplicate_name(de, fixed_name)) { | |
164 | /* Multiple duplicates. Retry with a different offset. */ | |
165 | i++; | |
166 | goto retry; | |
167 | } | |
168 | ||
169 | printk(KERN_WARNING "device-tree: Duplicate name in %s, " | |
170 | "renamed to \"%s\"\n", np->full_name, fixed_name); | |
171 | ||
172 | return fixed_name; | |
173 | } | |
174 | ||
1da177e4 LT |
175 | /* |
176 | * Process a node, adding entries for its children and its properties. | |
177 | */ | |
5f64f739 BH |
178 | void proc_device_tree_add_node(struct device_node *np, |
179 | struct proc_dir_entry *de) | |
1da177e4 LT |
180 | { |
181 | struct property *pp; | |
182 | struct proc_dir_entry *ent; | |
5f64f739 | 183 | struct device_node *child; |
5f64f739 | 184 | const char *p; |
1da177e4 LT |
185 | |
186 | set_node_proc_entry(np, de); | |
5f64f739 | 187 | for (child = NULL; (child = of_get_next_child(np, child));) { |
5149fa47 | 188 | /* Use everything after the last slash, or the full name */ |
1da177e4 LT |
189 | p = strrchr(child->full_name, '/'); |
190 | if (!p) | |
191 | p = child->full_name; | |
192 | else | |
193 | ++p; | |
5149fa47 ME |
194 | |
195 | if (duplicate_name(de, p)) | |
196 | p = fixup_name(np, de, p); | |
197 | ||
1da177e4 | 198 | ent = proc_mkdir(p, de); |
bcac2b1b | 199 | if (ent == NULL) |
1da177e4 | 200 | break; |
1da177e4 | 201 | proc_device_tree_add_node(child, ent); |
5f64f739 BH |
202 | } |
203 | of_node_put(child); | |
5149fa47 | 204 | |
bcac2b1b | 205 | for (pp = np->properties; pp != NULL; pp = pp->next) { |
5149fa47 ME |
206 | p = pp->name; |
207 | ||
208 | if (duplicate_name(de, p)) | |
209 | p = fixup_name(np, de, p); | |
5f64f739 | 210 | |
5149fa47 | 211 | ent = __proc_device_tree_add_prop(de, pp, p); |
bcac2b1b | 212 | if (ent == NULL) |
1da177e4 | 213 | break; |
1da177e4 | 214 | } |
1da177e4 LT |
215 | } |
216 | ||
217 | /* | |
218 | * Called on initialization to set up the /proc/device-tree subtree | |
219 | */ | |
1e0edd3f | 220 | void __init proc_device_tree_init(void) |
1da177e4 LT |
221 | { |
222 | struct device_node *root; | |
6b82b3e4 | 223 | |
1da177e4 | 224 | proc_device_tree = proc_mkdir("device-tree", NULL); |
bcac2b1b | 225 | if (proc_device_tree == NULL) |
1da177e4 LT |
226 | return; |
227 | root = of_find_node_by_path("/"); | |
bcac2b1b | 228 | if (root == NULL) { |
1da177e4 LT |
229 | printk(KERN_ERR "/proc/device-tree: can't find root\n"); |
230 | return; | |
231 | } | |
232 | proc_device_tree_add_node(root, proc_device_tree); | |
233 | of_node_put(root); | |
234 | } |