[deliverable/linux.git] / arch / powerpc / platforms / pseries / reconfig.c

/*
 * pSeries_reconfig.c - support for dynamic reconfiguration (including PCI
 * Hotplug and Dynamic Logical Partitioning on RPA platforms).
 *
 * Copyright (C) 2005 Nathan Lynch
 * Copyright (C) 2005 IBM Corporation
 *
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License version
 *	2 as published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/notifier.h>
#include <linux/proc_fs.h>
#include <linux/slab.h>
#include <linux/of.h>

#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/uaccess.h>
#include <asm/mmu.h>

/**
 *	derive_parent - basically like dirname(1)
 *	@path:  the full_name of a node to be added to the tree
 *
 *	Returns the node which should be the parent of the node
 *	described by path.  E.g., for path = "/foo/bar", returns
 *	the node with full_name = "/foo".
 */
static struct device_node *derive_parent(const char *path)
{
	struct device_node *parent = NULL;
	char *parent_path = "/";
	size_t parent_path_len = strrchr(path, '/') - path + 1;

	/* reject if path is "/" */
	if (!strcmp(path, "/"))
		return ERR_PTR(-EINVAL);

	if (strrchr(path, '/') != path) {
		parent_path = kmalloc(parent_path_len, GFP_KERNEL);
		if (!parent_path)
			return ERR_PTR(-ENOMEM);
		strlcpy(parent_path, path, parent_path_len);
	}
	parent = of_find_node_by_path(parent_path);
	if (!parent)
		return ERR_PTR(-EINVAL);
	if (strcmp(parent_path, "/"))
		kfree(parent_path);
	return parent;
}

static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
{
	struct device_node *np;
	int err = -ENOMEM;

	np = kzalloc(sizeof(*np), GFP_KERNEL);
	if (!np)
		goto out_err;

	np->full_name = kstrdup(path, GFP_KERNEL);
	if (!np->full_name)
		goto out_err;

	np->properties = proplist;
	of_node_set_flag(np, OF_DYNAMIC);

	np->parent = derive_parent(path);
	if (IS_ERR(np->parent)) {
		err = PTR_ERR(np->parent);
		goto out_err;
	}

	err = of_attach_node(np);
	if (err) {
		printk(KERN_ERR "Failed to add device node %s\n", path);
		goto out_err;
	}

	of_node_put(np->parent);

	return 0;

out_err:
	if (np) {
		of_node_put(np->parent);
		kfree(np->full_name);
		kfree(np);
	}
	return err;
}

static int pSeries_reconfig_remove_node(struct device_node *np)
{
	struct device_node *parent, *child;

	parent = of_get_parent(np);
	if (!parent)
		return -EINVAL;

	if ((child = of_get_next_child(np, NULL))) {
		of_node_put(child);
		of_node_put(parent);
		return -EBUSY;
	}

	of_detach_node(np);
	of_node_put(parent);
	of_node_put(np); /* Must decrement the refcount */
	return 0;
}

/*
 * /proc/powerpc/ofdt - yucky binary interface for adding and removing
 * OF device nodes.  Should be deprecated as soon as we get an
 * in-kernel wrapper for the RTAS ibm,configure-connector call.
 */

static void release_prop_list(const struct property *prop)
{
	struct property *next;
	for (; prop; prop = next) {
		next = prop->next;
		kfree(prop->name);
		kfree(prop->value);
		kfree(prop);
	}

}

/**
 * parse_next_property - process the next property from raw input buffer
 * @buf: input buffer, must be nul-terminated
 * @end: end of the input buffer + 1, for validation
 * @name: return value; set to property name in buf
 * @length: return value; set to length of value
 * @value: return value; set to the property value in buf
 *
 * Note that the caller must make copies of the name and value returned,
 * this function does no allocation or copying of the data.  Return value
 * is set to the next name in buf, or NULL on error.
 */
static char * parse_next_property(char *buf, char *end, char **name, int *length,
				  unsigned char **value)
{
	char *tmp;

	*name = buf;

	tmp = strchr(buf, ' ');
	if (!tmp) {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __func__, __LINE__);
		return NULL;
	}
	*tmp = '\0';

	if (++tmp >= end) {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __func__, __LINE__);
		return NULL;
	}

	/* now we're on the length */
	*length = -1;
	*length = simple_strtoul(tmp, &tmp, 10);
	if (*length == -1) {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __func__, __LINE__);
		return NULL;
	}
	if (*tmp != ' ' || ++tmp >= end) {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __func__, __LINE__);
		return NULL;
	}

	/* now we're on the value */
	*value = tmp;
	tmp += *length;
	if (tmp > end) {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __func__, __LINE__);
		return NULL;
	}
	else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __func__, __LINE__);
		return NULL;
	}
	tmp++;

	/* and now we should be on the next name, or the end */
	return tmp;
}

static struct property *new_property(const char *name, const int length,
				     const unsigned char *value, struct property *last)
{
	struct property *new = kzalloc(sizeof(*new), GFP_KERNEL);

	if (!new)
		return NULL;

	if (!(new->name = kstrdup(name, GFP_KERNEL)))
		goto cleanup;
	if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
		goto cleanup;

	memcpy(new->value, value, length);
	*(((char *)new->value) + length) = 0;
	new->length = length;
	new->next = last;
	return new;

cleanup:
	kfree(new->name);
	kfree(new->value);
	kfree(new);
	return NULL;
}

static int do_add_node(char *buf, size_t bufsize)
{
	char *path, *end, *name;
	struct device_node *np;
	struct property *prop = NULL;
	unsigned char* value;
	int length, rv = 0;

	end = buf + bufsize;
	path = buf;
	buf = strchr(buf, ' ');
	if (!buf)
		return -EINVAL;
	*buf = '\0';
	buf++;

	if ((np = of_find_node_by_path(path))) {
		of_node_put(np);
		return -EINVAL;
	}

	/* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
	while (buf < end &&
	       (buf = parse_next_property(buf, end, &name, &length, &value))) {
		struct property *last = prop;

		prop = new_property(name, length, value, last);
		if (!prop) {
			rv = -ENOMEM;
			prop = last;
			goto out;
		}
	}
	if (!buf) {
		rv = -EINVAL;
		goto out;
	}

	rv = pSeries_reconfig_add_node(path, prop);

out:
	if (rv)
		release_prop_list(prop);
	return rv;
}

static int do_remove_node(char *buf)
{
	struct device_node *node;
	int rv = -ENODEV;

	if ((node = of_find_node_by_path(buf)))
		rv = pSeries_reconfig_remove_node(node);

	of_node_put(node);
	return rv;
}

static char *parse_node(char *buf, size_t bufsize, struct device_node **npp)
{
	char *handle_str;
	phandle handle;
	*npp = NULL;

	handle_str = buf;

	buf = strchr(buf, ' ');
	if (!buf)
		return NULL;
	*buf = '\0';
	buf++;

	handle = simple_strtoul(handle_str, NULL, 0);

	*npp = of_find_node_by_phandle(handle);
	return buf;
}

static int do_add_property(char *buf, size_t bufsize)
{
	struct property *prop = NULL;
	struct device_node *np;
	unsigned char *value;
	char *name, *end;
	int length;
	end = buf + bufsize;
	buf = parse_node(buf, bufsize, &np);

	if (!np)
		return -ENODEV;

	if (parse_next_property(buf, end, &name, &length, &value) == NULL)
		return -EINVAL;

	prop = new_property(name, length, value, NULL);
	if (!prop)
		return -ENOMEM;

	of_add_property(np, prop);

	return 0;
}

static int do_remove_property(char *buf, size_t bufsize)
{
	struct device_node *np;
	char *tmp;
	struct property *prop;
	buf = parse_node(buf, bufsize, &np);

	if (!np)
		return -ENODEV;

	tmp = strchr(buf,' ');
	if (tmp)
		*tmp = '\0';

	if (strlen(buf) == 0)
		return -EINVAL;

	prop = of_find_property(np, buf, NULL);

	return of_remove_property(np, prop);
}

static int do_update_property(char *buf, size_t bufsize)
{
	struct device_node *np;
	unsigned char *value;
	char *name, *end, *next_prop;
	int length;
	struct property *newprop;
	buf = parse_node(buf, bufsize, &np);
	end = buf + bufsize;

	if (!np)
		return -ENODEV;

	next_prop = parse_next_property(buf, end, &name, &length, &value);
	if (!next_prop)
		return -EINVAL;

	if (!strlen(name))
		return -ENODEV;

	newprop = new_property(name, length, value, NULL);
	if (!newprop)
		return -ENOMEM;

	if (!strcmp(name, "slb-size") || !strcmp(name, "ibm,slb-size"))
		slb_set_size(*(int *)value);

	return of_update_property(np, newprop);
}

/**
 * ofdt_write - perform operations on the Open Firmware device tree
 *
 * @file: not used
 * @buf: command and arguments
 * @count: size of the command buffer
 * @off: not used
 *
 * Operations supported at this time are addition and removal of
 * whole nodes along with their properties.  Operations on individual
 * properties are not implemented (yet).
 */
static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
			  loff_t *off)
{
	int rv = 0;
	char *kbuf;
	char *tmp;

	if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
		rv = -ENOMEM;
		goto out;
	}
	if (copy_from_user(kbuf, buf, count)) {
		rv = -EFAULT;
		goto out;
	}

	kbuf[count] = '\0';

	tmp = strchr(kbuf, ' ');
	if (!tmp) {
		rv = -EINVAL;
		goto out;
	}
	*tmp = '\0';
	tmp++;

	if (!strcmp(kbuf, "add_node"))
		rv = do_add_node(tmp, count - (tmp - kbuf));
	else if (!strcmp(kbuf, "remove_node"))
		rv = do_remove_node(tmp);
	else if (!strcmp(kbuf, "add_property"))
		rv = do_add_property(tmp, count - (tmp - kbuf));
	else if (!strcmp(kbuf, "remove_property"))
		rv = do_remove_property(tmp, count - (tmp - kbuf));
	else if (!strcmp(kbuf, "update_property"))
		rv = do_update_property(tmp, count - (tmp - kbuf));
	else
		rv = -EINVAL;
out:
	kfree(kbuf);
	return rv ? rv : count;
}

static const struct file_operations ofdt_fops = {
	.write = ofdt_write,
	.llseek = noop_llseek,
};

/* create /proc/powerpc/ofdt write-only by root */
static int proc_ppc64_create_ofdt(void)
{
	struct proc_dir_entry *ent;

	if (!machine_is(pseries))
		return 0;

	ent = proc_create("powerpc/ofdt", S_IWUSR, NULL, &ofdt_fops);
	if (ent)
		proc_set_size(ent, 0);

	return 0;
}
__initcall(proc_ppc64_create_ofdt);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* pSeries_reconfig.c - support for dynamic reconfiguration (including PCI
	3	* Hotplug and Dynamic Logical Partitioning on RPA platforms).
	4	*
	5	* Copyright (C) 2005 Nathan Lynch
	6	* Copyright (C) 2005 IBM Corporation
	7	*
	8	*
	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.
	12	*/
	13
	14	#include <linux/kernel.h>
1da177e4 LT	15	#include <linux/notifier.h>
1da177e4 LT	16	#include <linux/proc_fs.h>
5a0e3ad6	17	#include <linux/slab.h>
1cf3d8b3	18	#include <linux/of.h>
1da177e4 LT	19
1da177e4 LT	20	#include <asm/prom.h>
e8222502	21	#include <asm/machdep.h>
1da177e4	22	#include <asm/uaccess.h>
46db2f86	23	#include <asm/mmu.h>
1da177e4	24
1da177e4 LT	25	/**
	26	* derive_parent - basically like dirname(1)
	27	* @path: the full_name of a node to be added to the tree
	28	*
	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".
	32	*/
	33	static struct device_node derive_parent(const char path)
	34	{
	35	struct device_node *parent = NULL;
	36	char *parent_path = "/";
	37	size_t parent_path_len = strrchr(path, '/') - path + 1;
	38
	39	/* reject if path is "/" */
	40	if (!strcmp(path, "/"))
	41	return ERR_PTR(-EINVAL);
	42
	43	if (strrchr(path, '/') != path) {
	44	parent_path = kmalloc(parent_path_len, GFP_KERNEL);
	45	if (!parent_path)
	46	return ERR_PTR(-ENOMEM);
	47	strlcpy(parent_path, path, parent_path_len);
	48	}
	49	parent = of_find_node_by_path(parent_path);
	50	if (!parent)
	51	return ERR_PTR(-EINVAL);
	52	if (strcmp(parent_path, "/"))
	53	kfree(parent_path);
	54	return parent;
	55	}
	56
1da177e4 LT	57	static int pSeries_reconfig_add_node(const char path, struct property proplist)
	58	{
	59	struct device_node *np;
	60	int err = -ENOMEM;
	61
874ca6cd	62	np = kzalloc(sizeof(*np), GFP_KERNEL);
1da177e4 LT	63	if (!np)
	64	goto out_err;
	65
74052173	66	np->full_name = kstrdup(path, GFP_KERNEL);
1da177e4 LT	67	if (!np->full_name)
	68	goto out_err;
	69
1da177e4	70	np->properties = proplist;
d3b814bb	71	of_node_set_flag(np, OF_DYNAMIC);
1da177e4 LT	72
	73	np->parent = derive_parent(path);
	74	if (IS_ERR(np->parent)) {
	75	err = PTR_ERR(np->parent);
	76	goto out_err;
	77	}
	78
1cf3d8b3	79	err = of_attach_node(np);
3aef19f0	80	if (err) {
1da177e4	81	printk(KERN_ERR "Failed to add device node %s\n", path);
1da177e4 LT	82	goto out_err;
	83	}
	84
1da177e4 LT	85	of_node_put(np->parent);
	86
	87	return 0;
	88
	89	out_err:
	90	if (np) {
	91	of_node_put(np->parent);
	92	kfree(np->full_name);
	93	kfree(np);
	94	}
	95	return err;
	96	}
	97
	98	static int pSeries_reconfig_remove_node(struct device_node *np)
	99	{
	100	struct device_node parent, child;
	101
	102	parent = of_get_parent(np);
	103	if (!parent)
	104	return -EINVAL;
	105
	106	if ((child = of_get_next_child(np, NULL))) {
	107	of_node_put(child);
842decbd	108	of_node_put(parent);
1da177e4 LT	109	return -EBUSY;
	110	}
	111
1da177e4	112	of_detach_node(np);
1da177e4 LT	113	of_node_put(parent);
	114	of_node_put(np); /* Must decrement the refcount */
	115	return 0;
	116	}
	117
	118	/*
188917e1	119	* /proc/powerpc/ofdt - yucky binary interface for adding and removing
1da177e4 LT	120	* OF device nodes. Should be deprecated as soon as we get an
	121	* in-kernel wrapper for the RTAS ibm,configure-connector call.
	122	*/
	123
	124	static void release_prop_list(const struct property *prop)
	125	{
	126	struct property *next;
	127	for (; prop; prop = next) {
	128	next = prop->next;
	129	kfree(prop->name);
	130	kfree(prop->value);
	131	kfree(prop);
	132	}
	133
	134	}
	135
	136	/**
	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
	143	*
	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.
	147	*/
	148	static char * parse_next_property(char buf, char end, char *name, int length,
	149	unsigned char **value)
	150	{
	151	char *tmp;
	152
	153	*name = buf;
	154
	155	tmp = strchr(buf, ' ');
	156	if (!tmp) {
	157	printk(KERN_ERR "property parse failed in %s at line %d\n",
e48b1b45	158	__func__, __LINE__);
1da177e4 LT	159	return NULL;
	160	}
	161	*tmp = '\0';
	162
	163	if (++tmp >= end) {
	164	printk(KERN_ERR "property parse failed in %s at line %d\n",
e48b1b45	165	__func__, __LINE__);
1da177e4 LT	166	return NULL;
	167	}
	168
	169	/* now we're on the length */
	170	*length = -1;
	171	*length = simple_strtoul(tmp, &tmp, 10);
	172	if (*length == -1) {
	173	printk(KERN_ERR "property parse failed in %s at line %d\n",
e48b1b45	174	__func__, __LINE__);
1da177e4 LT	175	return NULL;
	176	}
	177	if (*tmp != ' ' \|\| ++tmp >= end) {
	178	printk(KERN_ERR "property parse failed in %s at line %d\n",
e48b1b45	179	__func__, __LINE__);
1da177e4 LT	180	return NULL;
	181	}
	182
	183	/* now we're on the value */
	184	*value = tmp;
	185	tmp += *length;
	186	if (tmp > end) {
	187	printk(KERN_ERR "property parse failed in %s at line %d\n",
e48b1b45	188	__func__, __LINE__);
1da177e4 LT	189	return NULL;
	190	}
	191	else if (tmp < end && tmp != ' ' && tmp != '\0') {
	192	printk(KERN_ERR "property parse failed in %s at line %d\n",
e48b1b45	193	__func__, __LINE__);
1da177e4 LT	194	return NULL;
	195	}
	196	tmp++;
	197
	198	/* and now we should be on the next name, or the end */
	199	return tmp;
	200	}
	201
	202	static struct property new_property(const char name, const int length,
	203	const unsigned char value, struct property last)
	204	{
f8485350	205	struct property new = kzalloc(sizeof(new), GFP_KERNEL);
1da177e4 LT	206
	207	if (!new)
	208	return NULL;
1da177e4	209
c22618a1	210	if (!(new->name = kstrdup(name, GFP_KERNEL)))
1da177e4 LT	211	goto cleanup;
	212	if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
	213	goto cleanup;
	214
1da177e4 LT	215	memcpy(new->value, value, length);
	216	(((char )new->value) + length) = 0;
	217	new->length = length;
	218	new->next = last;
	219	return new;
	220
	221	cleanup:
b2325fe1 JJ	222	kfree(new->name);
b2325fe1 JJ	223	kfree(new->value);
1da177e4 LT	224	kfree(new);
	225	return NULL;
	226	}
	227
	228	static int do_add_node(char *buf, size_t bufsize)
	229	{
	230	char path, end, *name;
	231	struct device_node *np;
	232	struct property *prop = NULL;
	233	unsigned char* value;
	234	int length, rv = 0;
	235
	236	end = buf + bufsize;
	237	path = buf;
	238	buf = strchr(buf, ' ');
	239	if (!buf)
	240	return -EINVAL;
	241	*buf = '\0';
	242	buf++;
	243
	244	if ((np = of_find_node_by_path(path))) {
	245	of_node_put(np);
	246	return -EINVAL;
	247	}
	248
	249	/* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
	250	while (buf < end &&
	251	(buf = parse_next_property(buf, end, &name, &length, &value))) {
	252	struct property *last = prop;
	253
	254	prop = new_property(name, length, value, last);
	255	if (!prop) {
	256	rv = -ENOMEM;
	257	prop = last;
	258	goto out;
	259	}
	260	}
	261	if (!buf) {
	262	rv = -EINVAL;
	263	goto out;
	264	}
	265
	266	rv = pSeries_reconfig_add_node(path, prop);
	267
	268	out:
	269	if (rv)
	270	release_prop_list(prop);
	271	return rv;
	272	}
	273
	274	static int do_remove_node(char *buf)
	275	{
	276	struct device_node *node;
	277	int rv = -ENODEV;
	278
	279	if ((node = of_find_node_by_path(buf)))
	280	rv = pSeries_reconfig_remove_node(node);
	281
	282	of_node_put(node);
	283	return rv;
	284	}
	285
610d9151 DB	286	static char parse_node(char buf, size_t bufsize, struct device_node **npp)
	287	{
	288	char *handle_str;
	289	phandle handle;
	290	*npp = NULL;
	291
	292	handle_str = buf;
	293
	294	buf = strchr(buf, ' ');
	295	if (!buf)
	296	return NULL;
	297	*buf = '\0';
	298	buf++;
	299
4b6e805e	300	handle = simple_strtoul(handle_str, NULL, 0);
610d9151 DB	301
	302	*npp = of_find_node_by_phandle(handle);
	303	return buf;
	304	}
	305
	306	static int do_add_property(char *buf, size_t bufsize)
	307	{
	308	struct property *prop = NULL;
	309	struct device_node *np;
	310	unsigned char *value;
	311	char name, end;
	312	int length;
	313	end = buf + bufsize;
	314	buf = parse_node(buf, bufsize, &np);
	315
	316	if (!np)
	317	return -ENODEV;
	318
	319	if (parse_next_property(buf, end, &name, &length, &value) == NULL)
	320	return -EINVAL;
	321
	322	prop = new_property(name, length, value, NULL);
	323	if (!prop)
	324	return -ENOMEM;
	325
79d1c712	326	of_add_property(np, prop);
610d9151 DB	327
	328	return 0;
	329	}
	330
	331	static int do_remove_property(char *buf, size_t bufsize)
	332	{
	333	struct device_node *np;
	334	char *tmp;
	335	struct property *prop;
	336	buf = parse_node(buf, bufsize, &np);
	337
	338	if (!np)
	339	return -ENODEV;
	340
	341	tmp = strchr(buf,' ');
	342	if (tmp)
	343	*tmp = '\0';
	344
	345	if (strlen(buf) == 0)
	346	return -EINVAL;
	347
	348	prop = of_find_property(np, buf, NULL);
	349
79d1c712	350	return of_remove_property(np, prop);
610d9151 DB	351	}
	352
	353	static int do_update_property(char *buf, size_t bufsize)
	354	{
	355	struct device_node *np;
	356	unsigned char *value;
3c3f67ea	357	char name, end, *next_prop;
1cf3d8b3	358	int length;
475d0094	359	struct property *newprop;
610d9151 DB	360	buf = parse_node(buf, bufsize, &np);
	361	end = buf + bufsize;
	362
	363	if (!np)
	364	return -ENODEV;
	365
3c3f67ea NF	366	next_prop = parse_next_property(buf, end, &name, &length, &value);
3c3f67ea NF	367	if (!next_prop)
610d9151 DB	368	return -EINVAL;
610d9151 DB	369
475d0094 DA	370	if (!strlen(name))
	371	return -ENODEV;
	372
610d9151 DB	373	newprop = new_property(name, length, value, NULL);
	374	if (!newprop)
	375	return -ENOMEM;
	376
46db2f86 BK	377	if (!strcmp(name, "slb-size") \|\| !strcmp(name, "ibm,slb-size"))
	378	slb_set_size((int )value);
	379
79d1c712	380	return of_update_property(np, newprop);
610d9151 DB	381	}
610d9151 DB	382
1da177e4 LT	383	/**
	384	* ofdt_write - perform operations on the Open Firmware device tree
	385	*
	386	* @file: not used
	387	* @buf: command and arguments
	388	* @count: size of the command buffer
	389	* @off: not used
	390	*
	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).
	394	*/
	395	static ssize_t ofdt_write(struct file file, const char __user buf, size_t count,
	396	loff_t *off)
	397	{
	398	int rv = 0;
	399	char *kbuf;
	400	char *tmp;
	401
	402	if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
	403	rv = -ENOMEM;
	404	goto out;
	405	}
	406	if (copy_from_user(kbuf, buf, count)) {
	407	rv = -EFAULT;
	408	goto out;
	409	}
	410
	411	kbuf[count] = '\0';
	412
	413	tmp = strchr(kbuf, ' ');
	414	if (!tmp) {
	415	rv = -EINVAL;
	416	goto out;
	417	}
	418	*tmp = '\0';
	419	tmp++;
	420
	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);
610d9151 DB	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));
1da177e4 LT	431	else
	432	rv = -EINVAL;
	433	out:
	434	kfree(kbuf);
	435	return rv ? rv : count;
	436	}
	437
5dfe4c96	438	static const struct file_operations ofdt_fops = {
6038f373 AB	439	.write = ofdt_write,
6038f373 AB	440	.llseek = noop_llseek,
1da177e4 LT	441	};
1da177e4 LT	442
188917e1	443	/* create /proc/powerpc/ofdt write-only by root */
1da177e4 LT	444	static int proc_ppc64_create_ofdt(void)
	445	{
	446	struct proc_dir_entry *ent;
	447
e8222502	448	if (!machine_is(pseries))
1da177e4 LT	449	return 0;
1da177e4 LT	450
188917e1	451	ent = proc_create("powerpc/ofdt", S_IWUSR, NULL, &ofdt_fops);
66747138	452	if (ent)
271a15ea	453	proc_set_size(ent, 0);
1da177e4 LT	454
	455	return 0;
	456	}
	457	__initcall(proc_ppc64_create_ofdt);