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>
20 #include <asm/machdep.h>
21 #include <asm/uaccess.h>
22 #include <asm/pSeries_reconfig.h>
28 * Routines for "runtime" addition and removal of device tree nodes.
30 #ifdef CONFIG_PROC_DEVICETREE
32 * Add a node to /proc/device-tree.
34 static void add_node_proc_entries(struct device_node *np)
36 struct proc_dir_entry *ent;
38 ent = proc_mkdir(strrchr(np->full_name, '/') + 1, np->parent->pde);
40 proc_device_tree_add_node(np, ent);
43 static void remove_node_proc_entries(struct device_node *np)
45 struct property *pp = np->properties;
46 struct device_node *parent = np->parent;
49 remove_proc_entry(pp->name, np->pde);
53 remove_proc_entry(np->pde->name, parent->pde);
55 #else /* !CONFIG_PROC_DEVICETREE */
56 static void add_node_proc_entries(struct device_node *np)
61 static void remove_node_proc_entries(struct device_node *np)
65 #endif /* CONFIG_PROC_DEVICETREE */
68 * derive_parent - basically like dirname(1)
69 * @path: the full_name of a node to be added to the tree
71 * Returns the node which should be the parent of the node
72 * described by path. E.g., for path = "/foo/bar", returns
73 * the node with full_name = "/foo".
75 static struct device_node *derive_parent(const char *path)
77 struct device_node *parent = NULL;
78 char *parent_path = "/";
79 size_t parent_path_len = strrchr(path, '/') - path + 1;
81 /* reject if path is "/" */
82 if (!strcmp(path, "/"))
83 return ERR_PTR(-EINVAL);
85 if (strrchr(path, '/') != path) {
86 parent_path = kmalloc(parent_path_len, GFP_KERNEL);
88 return ERR_PTR(-ENOMEM);
89 strlcpy(parent_path, path, parent_path_len);
91 parent = of_find_node_by_path(parent_path);
93 return ERR_PTR(-EINVAL);
94 if (strcmp(parent_path, "/"))
99 static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
101 int pSeries_reconfig_notifier_register(struct notifier_block *nb)
103 return blocking_notifier_chain_register(&pSeries_reconfig_chain, nb);
106 void pSeries_reconfig_notifier_unregister(struct notifier_block *nb)
108 blocking_notifier_chain_unregister(&pSeries_reconfig_chain, nb);
111 static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
113 struct device_node *np;
116 np = kzalloc(sizeof(*np), GFP_KERNEL);
120 np->full_name = kmalloc(strlen(path) + 1, GFP_KERNEL);
124 strcpy(np->full_name, path);
126 np->properties = proplist;
127 of_node_set_flag(np, OF_DYNAMIC);
128 kref_init(&np->kref);
130 np->parent = derive_parent(path);
131 if (IS_ERR(np->parent)) {
132 err = PTR_ERR(np->parent);
136 err = blocking_notifier_call_chain(&pSeries_reconfig_chain,
137 PSERIES_RECONFIG_ADD, np);
138 if (err == NOTIFY_BAD) {
139 printk(KERN_ERR "Failed to add device node %s\n", path);
140 err = -ENOMEM; /* For now, safe to assume kmalloc failure */
146 add_node_proc_entries(np);
148 of_node_put(np->parent);
154 of_node_put(np->parent);
155 kfree(np->full_name);
161 static int pSeries_reconfig_remove_node(struct device_node *np)
163 struct device_node *parent, *child;
165 parent = of_get_parent(np);
169 if ((child = of_get_next_child(np, NULL))) {
175 remove_node_proc_entries(np);
177 blocking_notifier_call_chain(&pSeries_reconfig_chain,
178 PSERIES_RECONFIG_REMOVE, np);
182 of_node_put(np); /* Must decrement the refcount */
187 * /proc/powerpc/ofdt - yucky binary interface for adding and removing
188 * OF device nodes. Should be deprecated as soon as we get an
189 * in-kernel wrapper for the RTAS ibm,configure-connector call.
192 static void release_prop_list(const struct property *prop)
194 struct property *next;
195 for (; prop; prop = next) {
205 * parse_next_property - process the next property from raw input buffer
206 * @buf: input buffer, must be nul-terminated
207 * @end: end of the input buffer + 1, for validation
208 * @name: return value; set to property name in buf
209 * @length: return value; set to length of value
210 * @value: return value; set to the property value in buf
212 * Note that the caller must make copies of the name and value returned,
213 * this function does no allocation or copying of the data. Return value
214 * is set to the next name in buf, or NULL on error.
216 static char * parse_next_property(char *buf, char *end, char **name, int *length,
217 unsigned char **value)
223 tmp = strchr(buf, ' ');
225 printk(KERN_ERR "property parse failed in %s at line %d\n",
232 printk(KERN_ERR "property parse failed in %s at line %d\n",
237 /* now we're on the length */
239 *length = simple_strtoul(tmp, &tmp, 10);
241 printk(KERN_ERR "property parse failed in %s at line %d\n",
245 if (*tmp != ' ' || ++tmp >= end) {
246 printk(KERN_ERR "property parse failed in %s at line %d\n",
251 /* now we're on the value */
255 printk(KERN_ERR "property parse failed in %s at line %d\n",
259 else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
260 printk(KERN_ERR "property parse failed in %s at line %d\n",
266 /* and now we should be on the next name, or the end */
270 static struct property *new_property(const char *name, const int length,
271 const unsigned char *value, struct property *last)
273 struct property *new = kzalloc(sizeof(*new), GFP_KERNEL);
278 if (!(new->name = kmalloc(strlen(name) + 1, GFP_KERNEL)))
280 if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
283 strcpy(new->name, name);
284 memcpy(new->value, value, length);
285 *(((char *)new->value) + length) = 0;
286 new->length = length;
297 static int do_add_node(char *buf, size_t bufsize)
299 char *path, *end, *name;
300 struct device_node *np;
301 struct property *prop = NULL;
302 unsigned char* value;
307 buf = strchr(buf, ' ');
313 if ((np = of_find_node_by_path(path))) {
318 /* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
320 (buf = parse_next_property(buf, end, &name, &length, &value))) {
321 struct property *last = prop;
323 prop = new_property(name, length, value, last);
335 rv = pSeries_reconfig_add_node(path, prop);
339 release_prop_list(prop);
343 static int do_remove_node(char *buf)
345 struct device_node *node;
348 if ((node = of_find_node_by_path(buf)))
349 rv = pSeries_reconfig_remove_node(node);
355 static char *parse_node(char *buf, size_t bufsize, struct device_node **npp)
363 buf = strchr(buf, ' ');
369 handle = simple_strtoul(handle_str, NULL, 0);
371 *npp = of_find_node_by_phandle(handle);
375 static int do_add_property(char *buf, size_t bufsize)
377 struct property *prop = NULL;
378 struct device_node *np;
379 unsigned char *value;
383 buf = parse_node(buf, bufsize, &np);
388 if (parse_next_property(buf, end, &name, &length, &value) == NULL)
391 prop = new_property(name, length, value, NULL);
395 prom_add_property(np, prop);
400 static int do_remove_property(char *buf, size_t bufsize)
402 struct device_node *np;
404 struct property *prop;
405 buf = parse_node(buf, bufsize, &np);
410 tmp = strchr(buf,' ');
414 if (strlen(buf) == 0)
417 prop = of_find_property(np, buf, NULL);
419 return prom_remove_property(np, prop);
422 static int do_update_property(char *buf, size_t bufsize)
424 struct device_node *np;
425 unsigned char *value;
426 char *name, *end, *next_prop;
428 struct property *newprop, *oldprop;
429 buf = parse_node(buf, bufsize, &np);
435 next_prop = parse_next_property(buf, end, &name, &length, &value);
439 newprop = new_property(name, length, value, NULL);
443 if (!strcmp(name, "slb-size") || !strcmp(name, "ibm,slb-size"))
444 slb_set_size(*(int *)value);
446 oldprop = of_find_property(np, name,NULL);
449 return prom_add_property(np, newprop);
453 rc = prom_update_property(np, newprop, oldprop);
457 /* For memory under the ibm,dynamic-reconfiguration-memory node
458 * of the device tree, adding and removing memory is just an update
459 * to the ibm,dynamic-memory property instead of adding/removing a
460 * memory node in the device tree. For these cases we still need to
461 * involve the notifier chain.
463 if (!strcmp(name, "ibm,dynamic-memory")) {
466 next_prop = parse_next_property(next_prop, end, &name,
471 if (!strcmp(name, "add"))
472 action = PSERIES_DRCONF_MEM_ADD;
474 action = PSERIES_DRCONF_MEM_REMOVE;
476 rc = blocking_notifier_call_chain(&pSeries_reconfig_chain,
478 if (rc == NOTIFY_BAD) {
479 rc = prom_update_property(np, oldprop, newprop);
488 * ofdt_write - perform operations on the Open Firmware device tree
491 * @buf: command and arguments
492 * @count: size of the command buffer
495 * Operations supported at this time are addition and removal of
496 * whole nodes along with their properties. Operations on individual
497 * properties are not implemented (yet).
499 static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
506 if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
510 if (copy_from_user(kbuf, buf, count)) {
517 tmp = strchr(kbuf, ' ');
525 if (!strcmp(kbuf, "add_node"))
526 rv = do_add_node(tmp, count - (tmp - kbuf));
527 else if (!strcmp(kbuf, "remove_node"))
528 rv = do_remove_node(tmp);
529 else if (!strcmp(kbuf, "add_property"))
530 rv = do_add_property(tmp, count - (tmp - kbuf));
531 else if (!strcmp(kbuf, "remove_property"))
532 rv = do_remove_property(tmp, count - (tmp - kbuf));
533 else if (!strcmp(kbuf, "update_property"))
534 rv = do_update_property(tmp, count - (tmp - kbuf));
539 return rv ? rv : count;
542 static const struct file_operations ofdt_fops = {
546 /* create /proc/powerpc/ofdt write-only by root */
547 static int proc_ppc64_create_ofdt(void)
549 struct proc_dir_entry *ent;
551 if (!machine_is(pseries))
554 ent = proc_create("powerpc/ofdt", S_IWUSR, NULL, &ofdt_fops);
560 __initcall(proc_ppc64_create_ofdt);