linux/fs/proc/proc_devtree.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

165 lines
3.8 KiB
C

/*
* proc_devtree.c - handles /proc/device-tree
*
* Copyright 1997 Paul Mackerras
*/
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <asm/prom.h>
#include <asm/uaccess.h>
#ifndef HAVE_ARCH_DEVTREE_FIXUPS
static inline void set_node_proc_entry(struct device_node *np, struct proc_dir_entry *de)
{
}
static void inline set_node_name_link(struct device_node *np, struct proc_dir_entry *de)
{
}
static void inline set_node_addr_link(struct device_node *np, struct proc_dir_entry *de)
{
}
#endif
static struct proc_dir_entry *proc_device_tree;
/*
* Supply data on a read from /proc/device-tree/node/property.
*/
static int property_read_proc(char *page, char **start, off_t off,
int count, int *eof, void *data)
{
struct property *pp = data;
int n;
if (off >= pp->length) {
*eof = 1;
return 0;
}
n = pp->length - off;
if (n > count)
n = count;
else
*eof = 1;
memcpy(page, pp->value + off, n);
*start = page;
return n;
}
/*
* For a node with a name like "gc@10", we make symlinks called "gc"
* and "@10" to it.
*/
/*
* Process a node, adding entries for its children and its properties.
*/
void proc_device_tree_add_node(struct device_node *np, struct proc_dir_entry *de)
{
struct property *pp;
struct proc_dir_entry *ent;
struct device_node *child, *sib;
const char *p, *at;
int l;
struct proc_dir_entry *list, **lastp, *al;
set_node_proc_entry(np, de);
lastp = &list;
for (pp = np->properties; pp != 0; pp = pp->next) {
/*
* Unfortunately proc_register puts each new entry
* at the beginning of the list. So we rearrange them.
*/
ent = create_proc_read_entry(pp->name, strncmp(pp->name, "security-", 9) ?
S_IRUGO : S_IRUSR, de, property_read_proc, pp);
if (ent == 0)
break;
if (!strncmp(pp->name, "security-", 9))
ent->size = 0; /* don't leak number of password chars */
else
ent->size = pp->length;
*lastp = ent;
lastp = &ent->next;
}
child = NULL;
while ((child = of_get_next_child(np, child))) {
p = strrchr(child->full_name, '/');
if (!p)
p = child->full_name;
else
++p;
/* chop off '@0' if the name ends with that */
l = strlen(p);
if (l > 2 && p[l-2] == '@' && p[l-1] == '0')
l -= 2;
ent = proc_mkdir(p, de);
if (ent == 0)
break;
*lastp = ent;
lastp = &ent->next;
proc_device_tree_add_node(child, ent);
/*
* If we left the address part on the name, consider
* adding symlinks from the name and address parts.
*/
if (p[l] != 0 || (at = strchr(p, '@')) == 0)
continue;
/*
* If this is the first node with a given name property,
* add a symlink with the name property as its name.
*/
sib = NULL;
while ((sib = of_get_next_child(np, sib)) && sib != child)
if (sib->name && strcmp(sib->name, child->name) == 0)
break;
if (sib == child && strncmp(p, child->name, l) != 0) {
al = proc_symlink(child->name, de, ent->name);
if (al == 0) {
of_node_put(sib);
break;
}
set_node_name_link(child, al);
*lastp = al;
lastp = &al->next;
}
of_node_put(sib);
/*
* Add another directory with the @address part as its name.
*/
al = proc_symlink(at, de, ent->name);
if (al == 0)
break;
set_node_addr_link(child, al);
*lastp = al;
lastp = &al->next;
}
of_node_put(child);
*lastp = NULL;
de->subdir = list;
}
/*
* Called on initialization to set up the /proc/device-tree subtree
*/
void proc_device_tree_init(void)
{
struct device_node *root;
if ( !have_of )
return;
proc_device_tree = proc_mkdir("device-tree", NULL);
if (proc_device_tree == 0)
return;
root = of_find_node_by_path("/");
if (root == 0) {
printk(KERN_ERR "/proc/device-tree: can't find root\n");
return;
}
proc_device_tree_add_node(root, proc_device_tree);
of_node_put(root);
}