Commit | Line | Data |
---|---|---|
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> | |
50ab2fe1 | 13 | #include <linux/of.h> |
7c540d9e | 14 | #include <linux/module.h> |
5a0e3ad6 | 15 | #include <linux/slab.h> |
1da177e4 LT |
16 | #include <asm/prom.h> |
17 | #include <asm/uaccess.h> | |
3174c21b | 18 | #include "internal.h" |
1da177e4 | 19 | |
5f64f739 BH |
20 | static inline void set_node_proc_entry(struct device_node *np, |
21 | struct proc_dir_entry *de) | |
1da177e4 | 22 | { |
8cfb3343 JK |
23 | #ifdef HAVE_ARCH_DEVTREE_FIXUPS |
24 | np->pde = de; | |
1da177e4 | 25 | #endif |
8cfb3343 | 26 | } |
1da177e4 LT |
27 | |
28 | static struct proc_dir_entry *proc_device_tree; | |
29 | ||
30 | /* | |
31 | * Supply data on a read from /proc/device-tree/node/property. | |
32 | */ | |
e22f6283 | 33 | static int property_proc_show(struct seq_file *m, void *v) |
1da177e4 | 34 | { |
e22f6283 | 35 | struct property *pp = m->private; |
1da177e4 | 36 | |
e22f6283 AD |
37 | seq_write(m, pp->value, pp->length); |
38 | return 0; | |
1da177e4 LT |
39 | } |
40 | ||
e22f6283 AD |
41 | static int property_proc_open(struct inode *inode, struct file *file) |
42 | { | |
43 | return single_open(file, property_proc_show, PDE(inode)->data); | |
44 | } | |
45 | ||
46 | static const struct file_operations property_proc_fops = { | |
47 | .owner = THIS_MODULE, | |
48 | .open = property_proc_open, | |
49 | .read = seq_read, | |
50 | .llseek = seq_lseek, | |
51 | .release = single_release, | |
52 | }; | |
53 | ||
1da177e4 LT |
54 | /* |
55 | * For a node with a name like "gc@10", we make symlinks called "gc" | |
56 | * and "@10" to it. | |
57 | */ | |
58 | ||
183d0202 BH |
59 | /* |
60 | * Add a property to a node | |
61 | */ | |
62 | static struct proc_dir_entry * | |
5149fa47 ME |
63 | __proc_device_tree_add_prop(struct proc_dir_entry *de, struct property *pp, |
64 | const char *name) | |
183d0202 BH |
65 | { |
66 | struct proc_dir_entry *ent; | |
67 | ||
68 | /* | |
69 | * Unfortunately proc_register puts each new entry | |
70 | * at the beginning of the list. So we rearrange them. | |
71 | */ | |
e22f6283 AD |
72 | ent = proc_create_data(name, |
73 | strncmp(name, "security-", 9) ? S_IRUGO : S_IRUSR, | |
74 | de, &property_proc_fops, pp); | |
183d0202 BH |
75 | if (ent == NULL) |
76 | return NULL; | |
77 | ||
5149fa47 | 78 | if (!strncmp(name, "security-", 9)) |
183d0202 BH |
79 | ent->size = 0; /* don't leak number of password chars */ |
80 | else | |
81 | ent->size = pp->length; | |
82 | ||
83 | return ent; | |
84 | } | |
85 | ||
86 | ||
87 | void proc_device_tree_add_prop(struct proc_dir_entry *pde, struct property *prop) | |
88 | { | |
5149fa47 | 89 | __proc_device_tree_add_prop(pde, prop, prop->name); |
183d0202 BH |
90 | } |
91 | ||
898b5395 DB |
92 | void proc_device_tree_remove_prop(struct proc_dir_entry *pde, |
93 | struct property *prop) | |
94 | { | |
95 | remove_proc_entry(prop->name, pde); | |
96 | } | |
97 | ||
98 | void proc_device_tree_update_prop(struct proc_dir_entry *pde, | |
99 | struct property *newprop, | |
100 | struct property *oldprop) | |
101 | { | |
102 | struct proc_dir_entry *ent; | |
103 | ||
475d0094 DA |
104 | if (!oldprop) { |
105 | proc_device_tree_add_prop(pde, newprop); | |
106 | return; | |
107 | } | |
108 | ||
898b5395 DB |
109 | for (ent = pde->subdir; ent != NULL; ent = ent->next) |
110 | if (ent->data == oldprop) | |
111 | break; | |
112 | if (ent == NULL) { | |
113 | printk(KERN_WARNING "device-tree: property \"%s\" " | |
114 | " does not exist\n", oldprop->name); | |
115 | } else { | |
116 | ent->data = newprop; | |
117 | ent->size = newprop->length; | |
118 | } | |
119 | } | |
120 | ||
5149fa47 ME |
121 | /* |
122 | * Various dodgy firmware might give us nodes and/or properties with | |
123 | * conflicting names. That's generally ok, except for exporting via /proc, | |
124 | * so munge names here to ensure they're unique. | |
125 | */ | |
126 | ||
127 | static int duplicate_name(struct proc_dir_entry *de, const char *name) | |
128 | { | |
129 | struct proc_dir_entry *ent; | |
130 | int found = 0; | |
131 | ||
132 | spin_lock(&proc_subdir_lock); | |
133 | ||
134 | for (ent = de->subdir; ent != NULL; ent = ent->next) { | |
135 | if (strcmp(ent->name, name) == 0) { | |
136 | found = 1; | |
137 | break; | |
138 | } | |
139 | } | |
140 | ||
141 | spin_unlock(&proc_subdir_lock); | |
142 | ||
143 | return found; | |
144 | } | |
145 | ||
146 | static const char *fixup_name(struct device_node *np, struct proc_dir_entry *de, | |
147 | const char *name) | |
148 | { | |
149 | char *fixed_name; | |
150 | int fixup_len = strlen(name) + 2 + 1; /* name + #x + \0 */ | |
151 | int i = 1, size; | |
152 | ||
153 | realloc: | |
154 | fixed_name = kmalloc(fixup_len, GFP_KERNEL); | |
155 | if (fixed_name == NULL) { | |
156 | printk(KERN_ERR "device-tree: Out of memory trying to fixup " | |
157 | "name \"%s\"\n", name); | |
158 | return name; | |
159 | } | |
160 | ||
161 | retry: | |
162 | size = snprintf(fixed_name, fixup_len, "%s#%d", name, i); | |
163 | size++; /* account for NULL */ | |
164 | ||
165 | if (size > fixup_len) { | |
166 | /* We ran out of space, free and reallocate. */ | |
167 | kfree(fixed_name); | |
168 | fixup_len = size; | |
169 | goto realloc; | |
170 | } | |
171 | ||
172 | if (duplicate_name(de, fixed_name)) { | |
173 | /* Multiple duplicates. Retry with a different offset. */ | |
174 | i++; | |
175 | goto retry; | |
176 | } | |
177 | ||
178 | printk(KERN_WARNING "device-tree: Duplicate name in %s, " | |
179 | "renamed to \"%s\"\n", np->full_name, fixed_name); | |
180 | ||
181 | return fixed_name; | |
182 | } | |
183 | ||
1da177e4 LT |
184 | /* |
185 | * Process a node, adding entries for its children and its properties. | |
186 | */ | |
5f64f739 BH |
187 | void proc_device_tree_add_node(struct device_node *np, |
188 | struct proc_dir_entry *de) | |
1da177e4 LT |
189 | { |
190 | struct property *pp; | |
191 | struct proc_dir_entry *ent; | |
5f64f739 | 192 | struct device_node *child; |
5f64f739 | 193 | const char *p; |
1da177e4 LT |
194 | |
195 | set_node_proc_entry(np, de); | |
5f64f739 | 196 | for (child = NULL; (child = of_get_next_child(np, child));) { |
5149fa47 | 197 | /* Use everything after the last slash, or the full name */ |
1da177e4 LT |
198 | p = strrchr(child->full_name, '/'); |
199 | if (!p) | |
200 | p = child->full_name; | |
201 | else | |
202 | ++p; | |
5149fa47 ME |
203 | |
204 | if (duplicate_name(de, p)) | |
205 | p = fixup_name(np, de, p); | |
206 | ||
1da177e4 | 207 | ent = proc_mkdir(p, de); |
bcac2b1b | 208 | if (ent == NULL) |
1da177e4 | 209 | break; |
1da177e4 | 210 | proc_device_tree_add_node(child, ent); |
5f64f739 BH |
211 | } |
212 | of_node_put(child); | |
5149fa47 | 213 | |
bcac2b1b | 214 | for (pp = np->properties; pp != NULL; pp = pp->next) { |
5149fa47 ME |
215 | p = pp->name; |
216 | ||
9f069af5 ME |
217 | if (strchr(p, '/')) |
218 | continue; | |
219 | ||
5149fa47 ME |
220 | if (duplicate_name(de, p)) |
221 | p = fixup_name(np, de, p); | |
5f64f739 | 222 | |
5149fa47 | 223 | ent = __proc_device_tree_add_prop(de, pp, p); |
bcac2b1b | 224 | if (ent == NULL) |
1da177e4 | 225 | break; |
1da177e4 | 226 | } |
1da177e4 LT |
227 | } |
228 | ||
229 | /* | |
230 | * Called on initialization to set up the /proc/device-tree subtree | |
231 | */ | |
1e0edd3f | 232 | void __init proc_device_tree_init(void) |
1da177e4 LT |
233 | { |
234 | struct device_node *root; | |
6b82b3e4 | 235 | |
1da177e4 | 236 | proc_device_tree = proc_mkdir("device-tree", NULL); |
bcac2b1b | 237 | if (proc_device_tree == NULL) |
1da177e4 LT |
238 | return; |
239 | root = of_find_node_by_path("/"); | |
bcac2b1b | 240 | if (root == NULL) { |
8aaccf7f | 241 | pr_debug("/proc/device-tree: can't find root\n"); |
1da177e4 LT |
242 | return; |
243 | } | |
244 | proc_device_tree_add_node(root, proc_device_tree); | |
245 | of_node_put(root); | |
246 | } |