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/kref.h>
16 #include <linux/notifier.h>
17 #include <linux/proc_fs.h>
18 #include <linux/slab.h>
21 #include <asm/machdep.h>
22 #include <asm/uaccess.h>
23 #include <asm/pSeries_reconfig.h>
29 * Routines for "runtime" addition and removal of device tree nodes.
31 #ifdef CONFIG_PROC_DEVICETREE
33 * Add a node to /proc/device-tree.
35 static void add_node_proc_entries(struct device_node *np)
37 struct proc_dir_entry *ent;
39 ent = proc_mkdir(strrchr(np->full_name, '/') + 1, np->parent->pde);
41 proc_device_tree_add_node(np, ent);
44 static void remove_node_proc_entries(struct device_node *np)
46 struct property *pp = np->properties;
47 struct device_node *parent = np->parent;
50 remove_proc_entry(pp->name, np->pde);
54 remove_proc_entry(np->pde->name, parent->pde);
56 #else /* !CONFIG_PROC_DEVICETREE */
57 static void add_node_proc_entries(struct device_node *np)
62 static void remove_node_proc_entries(struct device_node *np)
66 #endif /* CONFIG_PROC_DEVICETREE */
69 * derive_parent - basically like dirname(1)
70 * @path: the full_name of a node to be added to the tree
72 * Returns the node which should be the parent of the node
73 * described by path. E.g., for path = "/foo/bar", returns
74 * the node with full_name = "/foo".
76 static struct device_node *derive_parent(const char *path)
78 struct device_node *parent = NULL;
79 char *parent_path = "/";
80 size_t parent_path_len = strrchr(path, '/') - path + 1;
82 /* reject if path is "/" */
83 if (!strcmp(path, "/"))
84 return ERR_PTR(-EINVAL);
86 if (strrchr(path, '/') != path) {
87 parent_path = kmalloc(parent_path_len, GFP_KERNEL);
89 return ERR_PTR(-ENOMEM);
90 strlcpy(parent_path, path, parent_path_len);
92 parent = of_find_node_by_path(parent_path);
94 return ERR_PTR(-EINVAL);
95 if (strcmp(parent_path, "/"))
100 static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
102 int pSeries_reconfig_notifier_register(struct notifier_block *nb)
104 return blocking_notifier_chain_register(&pSeries_reconfig_chain, nb);
106 EXPORT_SYMBOL_GPL(pSeries_reconfig_notifier_register);
108 void pSeries_reconfig_notifier_unregister(struct notifier_block *nb)
110 blocking_notifier_chain_unregister(&pSeries_reconfig_chain, nb);
112 EXPORT_SYMBOL_GPL(pSeries_reconfig_notifier_unregister);
114 int pSeries_reconfig_notify(unsigned long action, void *p)
116 int err = blocking_notifier_call_chain(&pSeries_reconfig_chain,
119 return notifier_to_errno(err);
122 static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
124 struct device_node *np;
127 np = kzalloc(sizeof(*np), GFP_KERNEL);
131 np->full_name = kstrdup(path, GFP_KERNEL);
135 np->properties = proplist;
136 of_node_set_flag(np, OF_DYNAMIC);
137 kref_init(&np->kref);
139 np->parent = derive_parent(path);
140 if (IS_ERR(np->parent)) {
141 err = PTR_ERR(np->parent);
145 err = pSeries_reconfig_notify(PSERIES_RECONFIG_ADD, np);
147 printk(KERN_ERR "Failed to add device node %s\n", path);
153 add_node_proc_entries(np);
155 of_node_put(np->parent);
161 of_node_put(np->parent);
162 kfree(np->full_name);
168 static int pSeries_reconfig_remove_node(struct device_node *np)
170 struct device_node *parent, *child;
172 parent = of_get_parent(np);
176 if ((child = of_get_next_child(np, NULL))) {
182 remove_node_proc_entries(np);
184 pSeries_reconfig_notify(PSERIES_RECONFIG_REMOVE, np);
188 of_node_put(np); /* Must decrement the refcount */
193 * /proc/powerpc/ofdt - yucky binary interface for adding and removing
194 * OF device nodes. Should be deprecated as soon as we get an
195 * in-kernel wrapper for the RTAS ibm,configure-connector call.
198 static void release_prop_list(const struct property *prop)
200 struct property *next;
201 for (; prop; prop = next) {
211 * parse_next_property - process the next property from raw input buffer
212 * @buf: input buffer, must be nul-terminated
213 * @end: end of the input buffer + 1, for validation
214 * @name: return value; set to property name in buf
215 * @length: return value; set to length of value
216 * @value: return value; set to the property value in buf
218 * Note that the caller must make copies of the name and value returned,
219 * this function does no allocation or copying of the data. Return value
220 * is set to the next name in buf, or NULL on error.
222 static char * parse_next_property(char *buf, char *end, char **name, int *length,
223 unsigned char **value)
229 tmp = strchr(buf, ' ');
231 printk(KERN_ERR "property parse failed in %s at line %d\n",
238 printk(KERN_ERR "property parse failed in %s at line %d\n",
243 /* now we're on the length */
245 *length = simple_strtoul(tmp, &tmp, 10);
247 printk(KERN_ERR "property parse failed in %s at line %d\n",
251 if (*tmp != ' ' || ++tmp >= end) {
252 printk(KERN_ERR "property parse failed in %s at line %d\n",
257 /* now we're on the value */
261 printk(KERN_ERR "property parse failed in %s at line %d\n",
265 else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
266 printk(KERN_ERR "property parse failed in %s at line %d\n",
272 /* and now we should be on the next name, or the end */
276 static struct property *new_property(const char *name, const int length,
277 const unsigned char *value, struct property *last)
279 struct property *new = kzalloc(sizeof(*new), GFP_KERNEL);
284 if (!(new->name = kmalloc(strlen(name) + 1, GFP_KERNEL)))
286 if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
289 strcpy(new->name, name);
290 memcpy(new->value, value, length);
291 *(((char *)new->value) + length) = 0;
292 new->length = length;
303 static int do_add_node(char *buf, size_t bufsize)
305 char *path, *end, *name;
306 struct device_node *np;
307 struct property *prop = NULL;
308 unsigned char* value;
313 buf = strchr(buf, ' ');
319 if ((np = of_find_node_by_path(path))) {
324 /* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
326 (buf = parse_next_property(buf, end, &name, &length, &value))) {
327 struct property *last = prop;
329 prop = new_property(name, length, value, last);
341 rv = pSeries_reconfig_add_node(path, prop);
345 release_prop_list(prop);
349 static int do_remove_node(char *buf)
351 struct device_node *node;
354 if ((node = of_find_node_by_path(buf)))
355 rv = pSeries_reconfig_remove_node(node);
361 static char *parse_node(char *buf, size_t bufsize, struct device_node **npp)
369 buf = strchr(buf, ' ');
375 handle = simple_strtoul(handle_str, NULL, 0);
377 *npp = of_find_node_by_phandle(handle);
381 static int do_add_property(char *buf, size_t bufsize)
383 struct property *prop = NULL;
384 struct device_node *np;
385 unsigned char *value;
389 buf = parse_node(buf, bufsize, &np);
394 if (parse_next_property(buf, end, &name, &length, &value) == NULL)
397 prop = new_property(name, length, value, NULL);
401 prom_add_property(np, prop);
406 static int do_remove_property(char *buf, size_t bufsize)
408 struct device_node *np;
410 struct property *prop;
411 buf = parse_node(buf, bufsize, &np);
416 tmp = strchr(buf,' ');
420 if (strlen(buf) == 0)
423 prop = of_find_property(np, buf, NULL);
425 return prom_remove_property(np, prop);
428 static int do_update_property(char *buf, size_t bufsize)
430 struct device_node *np;
431 struct pSeries_reconfig_prop_update upd_value;
432 unsigned char *value;
433 char *name, *end, *next_prop;
435 struct property *newprop, *oldprop;
436 buf = parse_node(buf, bufsize, &np);
442 next_prop = parse_next_property(buf, end, &name, &length, &value);
446 newprop = new_property(name, length, value, NULL);
450 if (!strcmp(name, "slb-size") || !strcmp(name, "ibm,slb-size"))
451 slb_set_size(*(int *)value);
453 oldprop = of_find_property(np, name,NULL);
456 return prom_add_property(np, newprop);
461 upd_value.property = newprop;
462 pSeries_reconfig_notify(PSERIES_UPDATE_PROPERTY, &upd_value);
464 rc = prom_update_property(np, newprop, oldprop);
468 /* For memory under the ibm,dynamic-reconfiguration-memory node
469 * of the device tree, adding and removing memory is just an update
470 * to the ibm,dynamic-memory property instead of adding/removing a
471 * memory node in the device tree. For these cases we still need to
472 * involve the notifier chain.
474 if (!strcmp(name, "ibm,dynamic-memory")) {
477 next_prop = parse_next_property(next_prop, end, &name,
482 if (!strcmp(name, "add"))
483 action = PSERIES_DRCONF_MEM_ADD;
485 action = PSERIES_DRCONF_MEM_REMOVE;
487 rc = pSeries_reconfig_notify(action, value);
489 prom_update_property(np, oldprop, newprop);
498 * ofdt_write - perform operations on the Open Firmware device tree
501 * @buf: command and arguments
502 * @count: size of the command buffer
505 * Operations supported at this time are addition and removal of
506 * whole nodes along with their properties. Operations on individual
507 * properties are not implemented (yet).
509 static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
516 if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
520 if (copy_from_user(kbuf, buf, count)) {
527 tmp = strchr(kbuf, ' ');
535 if (!strcmp(kbuf, "add_node"))
536 rv = do_add_node(tmp, count - (tmp - kbuf));
537 else if (!strcmp(kbuf, "remove_node"))
538 rv = do_remove_node(tmp);
539 else if (!strcmp(kbuf, "add_property"))
540 rv = do_add_property(tmp, count - (tmp - kbuf));
541 else if (!strcmp(kbuf, "remove_property"))
542 rv = do_remove_property(tmp, count - (tmp - kbuf));
543 else if (!strcmp(kbuf, "update_property"))
544 rv = do_update_property(tmp, count - (tmp - kbuf));
549 return rv ? rv : count;
552 static const struct file_operations ofdt_fops = {
554 .llseek = noop_llseek,
557 /* create /proc/powerpc/ofdt write-only by root */
558 static int proc_ppc64_create_ofdt(void)
560 struct proc_dir_entry *ent;
562 if (!machine_is(pseries))
565 ent = proc_create("powerpc/ofdt", S_IWUSR, NULL, &ofdt_fops);
571 __initcall(proc_ppc64_create_ofdt);