]>
git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - fs/proc/proc_devtree.c
2 * proc_devtree.c - handles /proc/device-tree
4 * Copyright 1997 Paul Mackerras
6 #include <linux/errno.h>
7 #include <linux/time.h>
8 #include <linux/proc_fs.h>
9 #include <linux/stat.h>
10 #include <linux/string.h>
12 #include <asm/uaccess.h>
14 #ifndef HAVE_ARCH_DEVTREE_FIXUPS
15 static inline void set_node_proc_entry(struct device_node
*np
,
16 struct proc_dir_entry
*de
)
21 static struct proc_dir_entry
*proc_device_tree
;
24 * Supply data on a read from /proc/device-tree/node/property.
26 static int property_read_proc(char *page
, char **start
, off_t off
,
27 int count
, int *eof
, void *data
)
29 struct property
*pp
= data
;
32 if (off
>= pp
->length
) {
41 memcpy(page
, (char *)pp
->value
+ off
, n
);
47 * For a node with a name like "gc@10", we make symlinks called "gc"
52 * Add a property to a node
54 static struct proc_dir_entry
*
55 __proc_device_tree_add_prop(struct proc_dir_entry
*de
, struct property
*pp
,
58 struct proc_dir_entry
*ent
;
61 * Unfortunately proc_register puts each new entry
62 * at the beginning of the list. So we rearrange them.
64 ent
= create_proc_read_entry(name
,
65 strncmp(name
, "security-", 9)
66 ? S_IRUGO
: S_IRUSR
, de
,
67 property_read_proc
, pp
);
71 if (!strncmp(name
, "security-", 9))
72 ent
->size
= 0; /* don't leak number of password chars */
74 ent
->size
= pp
->length
;
80 void proc_device_tree_add_prop(struct proc_dir_entry
*pde
, struct property
*prop
)
82 __proc_device_tree_add_prop(pde
, prop
, prop
->name
);
85 void proc_device_tree_remove_prop(struct proc_dir_entry
*pde
,
86 struct property
*prop
)
88 remove_proc_entry(prop
->name
, pde
);
91 void proc_device_tree_update_prop(struct proc_dir_entry
*pde
,
92 struct property
*newprop
,
93 struct property
*oldprop
)
95 struct proc_dir_entry
*ent
;
97 for (ent
= pde
->subdir
; ent
!= NULL
; ent
= ent
->next
)
98 if (ent
->data
== oldprop
)
101 printk(KERN_WARNING
"device-tree: property \"%s\" "
102 " does not exist\n", oldprop
->name
);
105 ent
->size
= newprop
->length
;
110 * Various dodgy firmware might give us nodes and/or properties with
111 * conflicting names. That's generally ok, except for exporting via /proc,
112 * so munge names here to ensure they're unique.
115 static int duplicate_name(struct proc_dir_entry
*de
, const char *name
)
117 struct proc_dir_entry
*ent
;
120 spin_lock(&proc_subdir_lock
);
122 for (ent
= de
->subdir
; ent
!= NULL
; ent
= ent
->next
) {
123 if (strcmp(ent
->name
, name
) == 0) {
129 spin_unlock(&proc_subdir_lock
);
134 static const char *fixup_name(struct device_node
*np
, struct proc_dir_entry
*de
,
138 int fixup_len
= strlen(name
) + 2 + 1; /* name + #x + \0 */
142 fixed_name
= kmalloc(fixup_len
, GFP_KERNEL
);
143 if (fixed_name
== NULL
) {
144 printk(KERN_ERR
"device-tree: Out of memory trying to fixup "
145 "name \"%s\"\n", name
);
150 size
= snprintf(fixed_name
, fixup_len
, "%s#%d", name
, i
);
151 size
++; /* account for NULL */
153 if (size
> fixup_len
) {
154 /* We ran out of space, free and reallocate. */
160 if (duplicate_name(de
, fixed_name
)) {
161 /* Multiple duplicates. Retry with a different offset. */
166 printk(KERN_WARNING
"device-tree: Duplicate name in %s, "
167 "renamed to \"%s\"\n", np
->full_name
, fixed_name
);
173 * Process a node, adding entries for its children and its properties.
175 void proc_device_tree_add_node(struct device_node
*np
,
176 struct proc_dir_entry
*de
)
179 struct proc_dir_entry
*ent
;
180 struct device_node
*child
;
183 set_node_proc_entry(np
, de
);
184 for (child
= NULL
; (child
= of_get_next_child(np
, child
));) {
185 /* Use everything after the last slash, or the full name */
186 p
= strrchr(child
->full_name
, '/');
188 p
= child
->full_name
;
192 if (duplicate_name(de
, p
))
193 p
= fixup_name(np
, de
, p
);
195 ent
= proc_mkdir(p
, de
);
198 proc_device_tree_add_node(child
, ent
);
202 for (pp
= np
->properties
; pp
!= 0; pp
= pp
->next
) {
205 if (duplicate_name(de
, p
))
206 p
= fixup_name(np
, de
, p
);
208 ent
= __proc_device_tree_add_prop(de
, pp
, p
);
215 * Called on initialization to set up the /proc/device-tree subtree
217 void proc_device_tree_init(void)
219 struct device_node
*root
;
222 proc_device_tree
= proc_mkdir("device-tree", NULL
);
223 if (proc_device_tree
== 0)
225 root
= of_find_node_by_path("/");
227 printk(KERN_ERR
"/proc/device-tree: can't find root\n");
230 proc_device_tree_add_node(root
, proc_device_tree
);