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/pSeries_reconfig.h>
21 #include <asm/uaccess.h>
26 * Routines for "runtime" addition and removal of device tree nodes.
28 #ifdef CONFIG_PROC_DEVICETREE
30 * Add a node to /proc/device-tree.
32 static void add_node_proc_entries(struct device_node *np)
34 struct proc_dir_entry *ent;
36 ent = proc_mkdir(strrchr(np->full_name, '/') + 1, np->parent->pde);
38 proc_device_tree_add_node(np, ent);
41 static void remove_node_proc_entries(struct device_node *np)
43 struct property *pp = np->properties;
44 struct device_node *parent = np->parent;
47 remove_proc_entry(pp->name, np->pde);
51 /* Assuming that symlinks have the same parent directory as
55 remove_proc_entry(np->name_link->name, parent->pde);
57 remove_proc_entry(np->addr_link->name, parent->pde);
59 remove_proc_entry(np->pde->name, parent->pde);
61 #else /* !CONFIG_PROC_DEVICETREE */
62 static void add_node_proc_entries(struct device_node *np)
67 static void remove_node_proc_entries(struct device_node *np)
71 #endif /* CONFIG_PROC_DEVICETREE */
74 * derive_parent - basically like dirname(1)
75 * @path: the full_name of a node to be added to the tree
77 * Returns the node which should be the parent of the node
78 * described by path. E.g., for path = "/foo/bar", returns
79 * the node with full_name = "/foo".
81 static struct device_node *derive_parent(const char *path)
83 struct device_node *parent = NULL;
84 char *parent_path = "/";
85 size_t parent_path_len = strrchr(path, '/') - path + 1;
87 /* reject if path is "/" */
88 if (!strcmp(path, "/"))
89 return ERR_PTR(-EINVAL);
91 if (strrchr(path, '/') != path) {
92 parent_path = kmalloc(parent_path_len, GFP_KERNEL);
94 return ERR_PTR(-ENOMEM);
95 strlcpy(parent_path, path, parent_path_len);
97 parent = of_find_node_by_path(parent_path);
99 return ERR_PTR(-EINVAL);
100 if (strcmp(parent_path, "/"))
105 static struct notifier_block *pSeries_reconfig_chain;
107 int pSeries_reconfig_notifier_register(struct notifier_block *nb)
109 return notifier_chain_register(&pSeries_reconfig_chain, nb);
112 void pSeries_reconfig_notifier_unregister(struct notifier_block *nb)
114 notifier_chain_unregister(&pSeries_reconfig_chain, nb);
117 static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
119 struct device_node *np;
122 np = kcalloc(1, sizeof(*np), GFP_KERNEL);
126 np->full_name = kmalloc(strlen(path) + 1, GFP_KERNEL);
130 strcpy(np->full_name, path);
132 np->properties = proplist;
134 kref_init(&np->kref);
136 np->parent = derive_parent(path);
137 if (IS_ERR(np->parent)) {
138 err = PTR_ERR(np->parent);
142 err = notifier_call_chain(&pSeries_reconfig_chain,
143 PSERIES_RECONFIG_ADD, np);
144 if (err == NOTIFY_BAD) {
145 printk(KERN_ERR "Failed to add device node %s\n", path);
146 err = -ENOMEM; /* For now, safe to assume kmalloc failure */
152 add_node_proc_entries(np);
154 of_node_put(np->parent);
160 of_node_put(np->parent);
161 kfree(np->full_name);
167 static int pSeries_reconfig_remove_node(struct device_node *np)
169 struct device_node *parent, *child;
171 parent = of_get_parent(np);
175 if ((child = of_get_next_child(np, NULL))) {
180 remove_node_proc_entries(np);
182 notifier_call_chain(&pSeries_reconfig_chain,
183 PSERIES_RECONFIG_REMOVE, np);
187 of_node_put(np); /* Must decrement the refcount */
192 * /proc/ppc64/ofdt - yucky binary interface for adding and removing
193 * OF device nodes. Should be deprecated as soon as we get an
194 * in-kernel wrapper for the RTAS ibm,configure-connector call.
197 static void release_prop_list(const struct property *prop)
199 struct property *next;
200 for (; prop; prop = next) {
210 * parse_next_property - process the next property from raw input buffer
211 * @buf: input buffer, must be nul-terminated
212 * @end: end of the input buffer + 1, for validation
213 * @name: return value; set to property name in buf
214 * @length: return value; set to length of value
215 * @value: return value; set to the property value in buf
217 * Note that the caller must make copies of the name and value returned,
218 * this function does no allocation or copying of the data. Return value
219 * is set to the next name in buf, or NULL on error.
221 static char * parse_next_property(char *buf, char *end, char **name, int *length,
222 unsigned char **value)
228 tmp = strchr(buf, ' ');
230 printk(KERN_ERR "property parse failed in %s at line %d\n",
231 __FUNCTION__, __LINE__);
237 printk(KERN_ERR "property parse failed in %s at line %d\n",
238 __FUNCTION__, __LINE__);
242 /* now we're on the length */
244 *length = simple_strtoul(tmp, &tmp, 10);
246 printk(KERN_ERR "property parse failed in %s at line %d\n",
247 __FUNCTION__, __LINE__);
250 if (*tmp != ' ' || ++tmp >= end) {
251 printk(KERN_ERR "property parse failed in %s at line %d\n",
252 __FUNCTION__, __LINE__);
256 /* now we're on the value */
260 printk(KERN_ERR "property parse failed in %s at line %d\n",
261 __FUNCTION__, __LINE__);
264 else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
265 printk(KERN_ERR "property parse failed in %s at line %d\n",
266 __FUNCTION__, __LINE__);
271 /* and now we should be on the next name, or the end */
275 static struct property *new_property(const char *name, const int length,
276 const unsigned char *value, struct property *last)
278 struct property *new = kmalloc(sizeof(*new), GFP_KERNEL);
282 memset(new, 0, sizeof(*new));
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;
305 static int do_add_node(char *buf, size_t bufsize)
307 char *path, *end, *name;
308 struct device_node *np;
309 struct property *prop = NULL;
310 unsigned char* value;
315 buf = strchr(buf, ' ');
321 if ((np = of_find_node_by_path(path))) {
326 /* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
328 (buf = parse_next_property(buf, end, &name, &length, &value))) {
329 struct property *last = prop;
331 prop = new_property(name, length, value, last);
343 rv = pSeries_reconfig_add_node(path, prop);
347 release_prop_list(prop);
351 static int do_remove_node(char *buf)
353 struct device_node *node;
356 if ((node = of_find_node_by_path(buf)))
357 rv = pSeries_reconfig_remove_node(node);
364 * ofdt_write - perform operations on the Open Firmware device tree
367 * @buf: command and arguments
368 * @count: size of the command buffer
371 * Operations supported at this time are addition and removal of
372 * whole nodes along with their properties. Operations on individual
373 * properties are not implemented (yet).
375 static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
382 if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
386 if (copy_from_user(kbuf, buf, count)) {
393 tmp = strchr(kbuf, ' ');
401 if (!strcmp(kbuf, "add_node"))
402 rv = do_add_node(tmp, count - (tmp - kbuf));
403 else if (!strcmp(kbuf, "remove_node"))
404 rv = do_remove_node(tmp);
409 return rv ? rv : count;
412 static struct file_operations ofdt_fops = {
416 /* create /proc/ppc64/ofdt write-only by root */
417 static int proc_ppc64_create_ofdt(void)
419 struct proc_dir_entry *ent;
421 if (!(systemcfg->platform & PLATFORM_PSERIES))
424 ent = create_proc_entry("ppc64/ofdt", S_IWUSR, NULL);
429 ent->proc_fops = &ofdt_fops;
434 __initcall(proc_ppc64_create_ofdt);