/* * 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) { } #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; struct proc_dir_entry *list = NULL, **lastp; const char *p; set_node_proc_entry(np, de); lastp = &list; for (child = NULL; (child = of_get_next_child(np, child));) { p = strrchr(child->full_name, '/'); if (!p) p = child->full_name; else ++p; ent = proc_mkdir(p, de); if (ent == 0) break; *lastp = ent; ent->next = NULL; lastp = &ent->next; proc_device_tree_add_node(child, ent); } of_node_put(child); for (pp = np->properties; pp != 0; pp = pp->next) { /* * Yet another Apple device-tree bogosity: on some machines, * they have properties & nodes with the same name. Those * properties are quite unimportant for us though, thus we * simply "skip" them here, but we do have to check. */ for (ent = list; ent != NULL; ent = ent->next) if (!strcmp(ent->name, pp->name)) break; if (ent != NULL) { printk(KERN_WARNING "device-tree: property \"%s\" name" " conflicts with node in %s\n", pp->name, np->full_name); continue; } /* * 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; ent->next = NULL; *lastp = ent; lastp = &ent->next; } 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); }