2 * pSeries_reconfig.c - support for dynamic reconfiguration (including PCI
3 * Hotplug and Dynamic Logical Partitioning on RPA platforms).
5 * Copyright (C) 2005 Nathan Lynch
6 * Copyright (C) 2005 IBM Corporation
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License version
11 * 2 as published by the Free Software Foundation.
14 #include <linux/kernel.h>
15 #include <linux/notifier.h>
16 #include <linux/proc_fs.h>
17 #include <linux/slab.h>
21 #include <asm/machdep.h>
22 #include <asm/uaccess.h>
26 * derive_parent - basically like dirname(1)
27 * @path: the full_name of a node to be added to the tree
29 * Returns the node which should be the parent of the node
30 * described by path. E.g., for path = "/foo/bar", returns
31 * the node with full_name = "/foo".
33 static struct device_node *derive_parent(const char *path)
35 struct device_node *parent = NULL;
36 char *parent_path = "/";
37 size_t parent_path_len = strrchr(path, '/') - path + 1;
39 /* reject if path is "/" */
40 if (!strcmp(path, "/"))
41 return ERR_PTR(-EINVAL);
43 if (strrchr(path, '/') != path) {
44 parent_path = kmalloc(parent_path_len, GFP_KERNEL);
46 return ERR_PTR(-ENOMEM);
47 strlcpy(parent_path, path, parent_path_len);
49 parent = of_find_node_by_path(parent_path);
51 return ERR_PTR(-EINVAL);
52 if (strcmp(parent_path, "/"))
57 static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
59 struct device_node *np;
62 np = kzalloc(sizeof(*np), GFP_KERNEL);
66 np->full_name = kstrdup(path, GFP_KERNEL);
70 np->properties = proplist;
71 of_node_set_flag(np, OF_DYNAMIC);
73 np->parent = derive_parent(path);
74 if (IS_ERR(np->parent)) {
75 err = PTR_ERR(np->parent);
79 err = of_attach_node(np);
81 printk(KERN_ERR "Failed to add device node %s\n", path);
85 of_node_put(np->parent);
91 of_node_put(np->parent);
98 static int pSeries_reconfig_remove_node(struct device_node *np)
100 struct device_node *parent, *child;
102 parent = of_get_parent(np);
106 if ((child = of_get_next_child(np, NULL))) {
114 of_node_put(np); /* Must decrement the refcount */
119 * /proc/powerpc/ofdt - yucky binary interface for adding and removing
120 * OF device nodes. Should be deprecated as soon as we get an
121 * in-kernel wrapper for the RTAS ibm,configure-connector call.
124 static void release_prop_list(const struct property *prop)
126 struct property *next;
127 for (; prop; prop = next) {
137 * parse_next_property - process the next property from raw input buffer
138 * @buf: input buffer, must be nul-terminated
139 * @end: end of the input buffer + 1, for validation
140 * @name: return value; set to property name in buf
141 * @length: return value; set to length of value
142 * @value: return value; set to the property value in buf
144 * Note that the caller must make copies of the name and value returned,
145 * this function does no allocation or copying of the data. Return value
146 * is set to the next name in buf, or NULL on error.
148 static char * parse_next_property(char *buf, char *end, char **name, int *length,
149 unsigned char **value)
155 tmp = strchr(buf, ' ');
157 printk(KERN_ERR "property parse failed in %s at line %d\n",
164 printk(KERN_ERR "property parse failed in %s at line %d\n",
169 /* now we're on the length */
171 *length = simple_strtoul(tmp, &tmp, 10);
173 printk(KERN_ERR "property parse failed in %s at line %d\n",
177 if (*tmp != ' ' || ++tmp >= end) {
178 printk(KERN_ERR "property parse failed in %s at line %d\n",
183 /* now we're on the value */
187 printk(KERN_ERR "property parse failed in %s at line %d\n",
191 else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
192 printk(KERN_ERR "property parse failed in %s at line %d\n",
198 /* and now we should be on the next name, or the end */
202 static struct property *new_property(const char *name, const int length,
203 const unsigned char *value, struct property *last)
205 struct property *new = kzalloc(sizeof(*new), GFP_KERNEL);
210 if (!(new->name = kstrdup(name, GFP_KERNEL)))
212 if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
215 memcpy(new->value, value, length);
216 *(((char *)new->value) + length) = 0;
217 new->length = length;
228 static int do_add_node(char *buf, size_t bufsize)
230 char *path, *end, *name;
231 struct device_node *np;
232 struct property *prop = NULL;
233 unsigned char* value;
238 buf = strchr(buf, ' ');
244 if ((np = of_find_node_by_path(path))) {
249 /* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
251 (buf = parse_next_property(buf, end, &name, &length, &value))) {
252 struct property *last = prop;
254 prop = new_property(name, length, value, last);
266 rv = pSeries_reconfig_add_node(path, prop);
270 release_prop_list(prop);
274 static int do_remove_node(char *buf)
276 struct device_node *node;
279 if ((node = of_find_node_by_path(buf)))
280 rv = pSeries_reconfig_remove_node(node);
286 static char *parse_node(char *buf, size_t bufsize, struct device_node **npp)
294 buf = strchr(buf, ' ');
300 handle = simple_strtoul(handle_str, NULL, 0);
302 *npp = of_find_node_by_phandle(handle);
306 static int do_add_property(char *buf, size_t bufsize)
308 struct property *prop = NULL;
309 struct device_node *np;
310 unsigned char *value;
314 buf = parse_node(buf, bufsize, &np);
319 if (parse_next_property(buf, end, &name, &length, &value) == NULL)
322 prop = new_property(name, length, value, NULL);
326 of_add_property(np, prop);
331 static int do_remove_property(char *buf, size_t bufsize)
333 struct device_node *np;
335 struct property *prop;
336 buf = parse_node(buf, bufsize, &np);
341 tmp = strchr(buf,' ');
345 if (strlen(buf) == 0)
348 prop = of_find_property(np, buf, NULL);
350 return of_remove_property(np, prop);
353 static int do_update_property(char *buf, size_t bufsize)
355 struct device_node *np;
356 unsigned char *value;
357 char *name, *end, *next_prop;
359 struct property *newprop;
360 buf = parse_node(buf, bufsize, &np);
366 next_prop = parse_next_property(buf, end, &name, &length, &value);
373 newprop = new_property(name, length, value, NULL);
377 if (!strcmp(name, "slb-size") || !strcmp(name, "ibm,slb-size"))
378 slb_set_size(*(int *)value);
380 return of_update_property(np, newprop);
384 * ofdt_write - perform operations on the Open Firmware device tree
387 * @buf: command and arguments
388 * @count: size of the command buffer
391 * Operations supported at this time are addition and removal of
392 * whole nodes along with their properties. Operations on individual
393 * properties are not implemented (yet).
395 static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
402 if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
406 if (copy_from_user(kbuf, buf, count)) {
413 tmp = strchr(kbuf, ' ');
421 if (!strcmp(kbuf, "add_node"))
422 rv = do_add_node(tmp, count - (tmp - kbuf));
423 else if (!strcmp(kbuf, "remove_node"))
424 rv = do_remove_node(tmp);
425 else if (!strcmp(kbuf, "add_property"))
426 rv = do_add_property(tmp, count - (tmp - kbuf));
427 else if (!strcmp(kbuf, "remove_property"))
428 rv = do_remove_property(tmp, count - (tmp - kbuf));
429 else if (!strcmp(kbuf, "update_property"))
430 rv = do_update_property(tmp, count - (tmp - kbuf));
435 return rv ? rv : count;
438 static const struct file_operations ofdt_fops = {
440 .llseek = noop_llseek,
443 /* create /proc/powerpc/ofdt write-only by root */
444 static int proc_ppc64_create_ofdt(void)
446 struct proc_dir_entry *ent;
448 if (!machine_is(pseries))
451 ent = proc_create("powerpc/ofdt", S_IWUSR, NULL, &ofdt_fops);
453 proc_set_size(ent, 0);
457 __initcall(proc_ppc64_create_ofdt);