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