[mirror_ubuntu-artful-kernel.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/kref.h>
#include <linux/notifier.h>
#include <linux/proc_fs.h>

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


/*
 * Routines for "runtime" addition and removal of device tree nodes.
 */
#ifdef CONFIG_PROC_DEVICETREE
/*
 * Add a node to /proc/device-tree.
 */
static void add_node_proc_entries(struct device_node *np)
{
	struct proc_dir_entry *ent;

	ent = proc_mkdir(strrchr(np->full_name, '/') + 1, np->parent->pde);
	if (ent)
		proc_device_tree_add_node(np, ent);
}

static void remove_node_proc_entries(struct device_node *np)
{
	struct property *pp = np->properties;
	struct device_node *parent = np->parent;

	while (pp) {
		remove_proc_entry(pp->name, np->pde);
		pp = pp->next;
	}
	if (np->pde)
		remove_proc_entry(np->pde->name, parent->pde);
}
#else /* !CONFIG_PROC_DEVICETREE */
static void add_node_proc_entries(struct device_node *np)
{
	return;
}

static void remove_node_proc_entries(struct device_node *np)
{
	return;
}
#endif /* CONFIG_PROC_DEVICETREE */

/**
 *	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 BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);

int pSeries_reconfig_notifier_register(struct notifier_block *nb)
{
	return blocking_notifier_chain_register(&pSeries_reconfig_chain, nb);
}

void pSeries_reconfig_notifier_unregister(struct notifier_block *nb)
{
	blocking_notifier_chain_unregister(&pSeries_reconfig_chain, nb);
}

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 = kmalloc(strlen(path) + 1, GFP_KERNEL);
	if (!np->full_name)
		goto out_err;

	strcpy(np->full_name, path);

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

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

	err = blocking_notifier_call_chain(&pSeries_reconfig_chain,
				  PSERIES_RECONFIG_ADD, np);
	if (err == NOTIFY_BAD) {
		printk(KERN_ERR "Failed to add device node %s\n", path);
		err = -ENOMEM; /* For now, safe to assume kmalloc failure */
		goto out_err;
	}

	of_attach_node(np);

	add_node_proc_entries(np);

	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);
		return -EBUSY;
	}

	remove_node_proc_entries(np);

	blocking_notifier_call_chain(&pSeries_reconfig_chain,
			    PSERIES_RECONFIG_REMOVE, np);
	of_detach_node(np);

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

/*
 * /proc/ppc64/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",
		       __FUNCTION__, __LINE__);
		return NULL;
	}
	*tmp = '\0';

	if (++tmp >= end) {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __FUNCTION__, __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",
		       __FUNCTION__, __LINE__);
		return NULL;
	}
	if (*tmp != ' ' || ++tmp >= end) {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __FUNCTION__, __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",
		       __FUNCTION__, __LINE__);
		return NULL;
	}
	else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
		printk(KERN_ERR "property parse failed in %s at line %d\n",
		       __FUNCTION__, __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 = kmalloc(strlen(name) + 1, GFP_KERNEL)))
		goto cleanup;
	if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
		goto cleanup;

	strcpy(new->name, name);
	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, 10);

	*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;

	prom_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 prom_remove_property(np, prop);
}

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

	if (!np)
		return -ENODEV;

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

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

	oldprop = of_find_property(np, name,NULL);
	if (!oldprop)
		return -ENODEV;

	return prom_update_property(np, newprop, oldprop);
}

/**
 * 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
};

/* create /proc/ppc64/ofdt write-only by root */
static int proc_ppc64_create_ofdt(void)
{
	struct proc_dir_entry *ent;

	if (!machine_is(pseries))
		return 0;

	ent = create_proc_entry("ppc64/ofdt", S_IWUSR, NULL);
	if (ent) {
		ent->data = NULL;
		ent->size = 0;
		ent->proc_fops = &ofdt_fops;
	}

	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>
	15	#include <linux/kref.h>
	16	#include <linux/notifier.h>
	17	#include <linux/proc_fs.h>
	18
	19	#include <asm/prom.h>
e8222502	20	#include <asm/machdep.h>
1da177e4	21	#include <asm/uaccess.h>
e8222502	22	#include <asm/pSeries_reconfig.h>
1da177e4 LT	23
	24
	25
	26	/*
	27	* Routines for "runtime" addition and removal of device tree nodes.
	28	*/
	29	#ifdef CONFIG_PROC_DEVICETREE
	30	/*
	31	* Add a node to /proc/device-tree.
	32	*/
	33	static void add_node_proc_entries(struct device_node *np)
	34	{
	35	struct proc_dir_entry *ent;
	36
	37	ent = proc_mkdir(strrchr(np->full_name, '/') + 1, np->parent->pde);
	38	if (ent)
	39	proc_device_tree_add_node(np, ent);
	40	}
	41
	42	static void remove_node_proc_entries(struct device_node *np)
	43	{
	44	struct property *pp = np->properties;
	45	struct device_node *parent = np->parent;
	46
	47	while (pp) {
	48	remove_proc_entry(pp->name, np->pde);
	49	pp = pp->next;
	50	}
1da177e4 LT	51	if (np->pde)
	52	remove_proc_entry(np->pde->name, parent->pde);
	53	}
	54	#else /* !CONFIG_PROC_DEVICETREE */
	55	static void add_node_proc_entries(struct device_node *np)
	56	{
	57	return;
	58	}
	59
	60	static void remove_node_proc_entries(struct device_node *np)
	61	{
	62	return;
	63	}
	64	#endif /* CONFIG_PROC_DEVICETREE */
	65
	66	/**
	67	* derive_parent - basically like dirname(1)
	68	* @path: the full_name of a node to be added to the tree
	69	*
	70	* Returns the node which should be the parent of the node
	71	* described by path. E.g., for path = "/foo/bar", returns
	72	* the node with full_name = "/foo".
	73	*/
	74	static struct device_node derive_parent(const char path)
	75	{
	76	struct device_node *parent = NULL;
	77	char *parent_path = "/";
	78	size_t parent_path_len = strrchr(path, '/') - path + 1;
	79
	80	/* reject if path is "/" */
	81	if (!strcmp(path, "/"))
	82	return ERR_PTR(-EINVAL);
	83
	84	if (strrchr(path, '/') != path) {
	85	parent_path = kmalloc(parent_path_len, GFP_KERNEL);
	86	if (!parent_path)
	87	return ERR_PTR(-ENOMEM);
	88	strlcpy(parent_path, path, parent_path_len);
	89	}
	90	parent = of_find_node_by_path(parent_path);
	91	if (!parent)
	92	return ERR_PTR(-EINVAL);
	93	if (strcmp(parent_path, "/"))
	94	kfree(parent_path);
	95	return parent;
	96	}
	97
e041c683	98	static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
1da177e4 LT	99
	100	int pSeries_reconfig_notifier_register(struct notifier_block *nb)
	101	{
e041c683	102	return blocking_notifier_chain_register(&pSeries_reconfig_chain, nb);
1da177e4 LT	103	}
	104
	105	void pSeries_reconfig_notifier_unregister(struct notifier_block *nb)
	106	{
e041c683	107	blocking_notifier_chain_unregister(&pSeries_reconfig_chain, nb);
1da177e4 LT	108	}
	109
	110	static int pSeries_reconfig_add_node(const char path, struct property proplist)
	111	{
	112	struct device_node *np;
	113	int err = -ENOMEM;
	114
874ca6cd	115	np = kzalloc(sizeof(*np), GFP_KERNEL);
1da177e4 LT	116	if (!np)
	117	goto out_err;
	118
	119	np->full_name = kmalloc(strlen(path) + 1, GFP_KERNEL);
	120	if (!np->full_name)
	121	goto out_err;
	122
	123	strcpy(np->full_name, path);
	124
	125	np->properties = proplist;
d3b814bb	126	of_node_set_flag(np, OF_DYNAMIC);
1da177e4 LT	127	kref_init(&np->kref);
	128
	129	np->parent = derive_parent(path);
	130	if (IS_ERR(np->parent)) {
	131	err = PTR_ERR(np->parent);
	132	goto out_err;
	133	}
	134
e041c683	135	err = blocking_notifier_call_chain(&pSeries_reconfig_chain,
1da177e4 LT	136	PSERIES_RECONFIG_ADD, np);
	137	if (err == NOTIFY_BAD) {
	138	printk(KERN_ERR "Failed to add device node %s\n", path);
	139	err = -ENOMEM; /* For now, safe to assume kmalloc failure */
	140	goto out_err;
	141	}
	142
	143	of_attach_node(np);
	144
	145	add_node_proc_entries(np);
	146
	147	of_node_put(np->parent);
	148
	149	return 0;
	150
	151	out_err:
	152	if (np) {
	153	of_node_put(np->parent);
	154	kfree(np->full_name);
	155	kfree(np);
	156	}
	157	return err;
	158	}
	159
	160	static int pSeries_reconfig_remove_node(struct device_node *np)
	161	{
	162	struct device_node parent, child;
	163
	164	parent = of_get_parent(np);
	165	if (!parent)
	166	return -EINVAL;
	167
	168	if ((child = of_get_next_child(np, NULL))) {
	169	of_node_put(child);
	170	return -EBUSY;
	171	}
	172
	173	remove_node_proc_entries(np);
	174
e041c683	175	blocking_notifier_call_chain(&pSeries_reconfig_chain,
1da177e4 LT	176	PSERIES_RECONFIG_REMOVE, np);
	177	of_detach_node(np);
	178
	179	of_node_put(parent);
	180	of_node_put(np); /* Must decrement the refcount */
	181	return 0;
	182	}
	183
	184	/*
	185	* /proc/ppc64/ofdt - yucky binary interface for adding and removing
	186	* OF device nodes. Should be deprecated as soon as we get an
	187	* in-kernel wrapper for the RTAS ibm,configure-connector call.
	188	*/
	189
	190	static void release_prop_list(const struct property *prop)
	191	{
	192	struct property *next;
	193	for (; prop; prop = next) {
	194	next = prop->next;
	195	kfree(prop->name);
	196	kfree(prop->value);
	197	kfree(prop);
	198	}
	199
	200	}
	201
	202	/**
	203	* parse_next_property - process the next property from raw input buffer
	204	* @buf: input buffer, must be nul-terminated
	205	* @end: end of the input buffer + 1, for validation
	206	* @name: return value; set to property name in buf
	207	* @length: return value; set to length of value
	208	* @value: return value; set to the property value in buf
	209	*
	210	* Note that the caller must make copies of the name and value returned,
	211	* this function does no allocation or copying of the data. Return value
	212	* is set to the next name in buf, or NULL on error.
	213	*/
	214	static char * parse_next_property(char buf, char end, char *name, int length,
	215	unsigned char **value)
	216	{
	217	char *tmp;
	218
	219	*name = buf;
	220
	221	tmp = strchr(buf, ' ');
	222	if (!tmp) {
	223	printk(KERN_ERR "property parse failed in %s at line %d\n",
	224	__FUNCTION__, __LINE__);
	225	return NULL;
	226	}
	227	*tmp = '\0';
	228
	229	if (++tmp >= end) {
	230	printk(KERN_ERR "property parse failed in %s at line %d\n",
	231	__FUNCTION__, __LINE__);
	232	return NULL;
	233	}
	234
	235	/* now we're on the length */
	236	*length = -1;
	237	*length = simple_strtoul(tmp, &tmp, 10);
	238	if (*length == -1) {
	239	printk(KERN_ERR "property parse failed in %s at line %d\n",
240	__FUNCTION__, __LINE__);
241	return NULL;
242	}
243	if (*tmp != ' ' \|\| ++tmp >= end) {
244	printk(KERN_ERR "property parse failed in %s at line %d\n",
245	__FUNCTION__, __LINE__);
246	return NULL;
247	}
248
249	/* now we're on the value */
250	*value = tmp;
251	tmp += *length;
252	if (tmp > end) {
253	printk(KERN_ERR "property parse failed in %s at line %d\n",
254	__FUNCTION__, __LINE__);
255	return NULL;
256	}
257	else if (tmp < end && tmp != ' ' && tmp != '\0') {
258	printk(KERN_ERR "property parse failed in %s at line %d\n",
259	__FUNCTION__, __LINE__);
260	return NULL;
261	}
262	tmp++;
263
264	/* and now we should be on the next name, or the end */
265	return tmp;
266	}
267
268	static struct property new_property(const char name, const int length,
269	const unsigned char value, struct property last)
270	{
f8485350	271	struct property new = kzalloc(sizeof(new), GFP_KERNEL);
1da177e4 LT	272
	273	if (!new)
	274	return NULL;
1da177e4 LT	275
	276	if (!(new->name = kmalloc(strlen(name) + 1, GFP_KERNEL)))
	277	goto cleanup;
	278	if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
	279	goto cleanup;
	280
	281	strcpy(new->name, name);
	282	memcpy(new->value, value, length);
	283	(((char )new->value) + length) = 0;
	284	new->length = length;
	285	new->next = last;
	286	return new;
	287
	288	cleanup:
b2325fe1 JJ	289	kfree(new->name);
b2325fe1 JJ	290	kfree(new->value);
1da177e4 LT	291	kfree(new);
	292	return NULL;
	293	}
	294
	295	static int do_add_node(char *buf, size_t bufsize)
	296	{
	297	char path, end, *name;
	298	struct device_node *np;
	299	struct property *prop = NULL;
	300	unsigned char* value;
	301	int length, rv = 0;
	302
	303	end = buf + bufsize;
	304	path = buf;
	305	buf = strchr(buf, ' ');
	306	if (!buf)
	307	return -EINVAL;
	308	*buf = '\0';
	309	buf++;
	310
	311	if ((np = of_find_node_by_path(path))) {
	312	of_node_put(np);
	313	return -EINVAL;
	314	}
	315
	316	/* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
	317	while (buf < end &&
	318	(buf = parse_next_property(buf, end, &name, &length, &value))) {
	319	struct property *last = prop;
	320
	321	prop = new_property(name, length, value, last);
	322	if (!prop) {
	323	rv = -ENOMEM;
	324	prop = last;
	325	goto out;
	326	}
	327	}
	328	if (!buf) {
	329	rv = -EINVAL;
	330	goto out;
	331	}
	332
	333	rv = pSeries_reconfig_add_node(path, prop);
	334
	335	out:
	336	if (rv)
	337	release_prop_list(prop);
	338	return rv;
	339	}
	340
	341	static int do_remove_node(char *buf)
	342	{
	343	struct device_node *node;
	344	int rv = -ENODEV;
	345
	346	if ((node = of_find_node_by_path(buf)))
	347	rv = pSeries_reconfig_remove_node(node);
	348
	349	of_node_put(node);
	350	return rv;
	351	}
	352
610d9151 DB	353	static char parse_node(char buf, size_t bufsize, struct device_node **npp)
	354	{
	355	char *handle_str;
	356	phandle handle;
	357	*npp = NULL;
	358
	359	handle_str = buf;
	360
	361	buf = strchr(buf, ' ');
	362	if (!buf)
	363	return NULL;
	364	*buf = '\0';
	365	buf++;
	366
	367	handle = simple_strtoul(handle_str, NULL, 10);
	368
	369	*npp = of_find_node_by_phandle(handle);
	370	return buf;
	371	}
	372
	373	static int do_add_property(char *buf, size_t bufsize)
	374	{
	375	struct property *prop = NULL;
	376	struct device_node *np;
	377	unsigned char *value;
	378	char name, end;
	379	int length;
	380	end = buf + bufsize;
	381	buf = parse_node(buf, bufsize, &np);
	382
	383	if (!np)
	384	return -ENODEV;
	385
	386	if (parse_next_property(buf, end, &name, &length, &value) == NULL)
	387	return -EINVAL;
	388
	389	prop = new_property(name, length, value, NULL);
	390	if (!prop)
	391	return -ENOMEM;
	392
	393	prom_add_property(np, prop);
	394
	395	return 0;
	396	}
	397
	398	static int do_remove_property(char *buf, size_t bufsize)
	399	{
	400	struct device_node *np;
	401	char *tmp;
	402	struct property *prop;
	403	buf = parse_node(buf, bufsize, &np);
	404
	405	if (!np)
	406	return -ENODEV;
	407
	408	tmp = strchr(buf,' ');
	409	if (tmp)
	410	*tmp = '\0';
	411
	412	if (strlen(buf) == 0)
	413	return -EINVAL;
	414
	415	prop = of_find_property(np, buf, NULL);
	416
417	return prom_remove_property(np, prop);
418	}
419
420	static int do_update_property(char *buf, size_t bufsize)
421	{
422	struct device_node *np;
423	unsigned char *value;
424	char name, end;
425	int length;
426	struct property newprop, oldprop;
427	buf = parse_node(buf, bufsize, &np);
428	end = buf + bufsize;
429
430	if (!np)
431	return -ENODEV;
432
433	if (parse_next_property(buf, end, &name, &length, &value) == NULL)
434	return -EINVAL;
435
436	newprop = new_property(name, length, value, NULL);
437	if (!newprop)
438	return -ENOMEM;
439
440	oldprop = of_find_property(np, name,NULL);
441	if (!oldprop)
442	return -ENODEV;
443
444	return prom_update_property(np, newprop, oldprop);
445	}
446
1da177e4 LT	447	/**
	448	* ofdt_write - perform operations on the Open Firmware device tree
	449	*
	450	* @file: not used
	451	* @buf: command and arguments
	452	* @count: size of the command buffer
	453	* @off: not used
	454	*
	455	* Operations supported at this time are addition and removal of
	456	* whole nodes along with their properties. Operations on individual
	457	* properties are not implemented (yet).
	458	*/
	459	static ssize_t ofdt_write(struct file file, const char __user buf, size_t count,
	460	loff_t *off)
	461	{
	462	int rv = 0;
	463	char *kbuf;
	464	char *tmp;
	465
	466	if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
	467	rv = -ENOMEM;
	468	goto out;
	469	}
	470	if (copy_from_user(kbuf, buf, count)) {
	471	rv = -EFAULT;
	472	goto out;
	473	}
	474
	475	kbuf[count] = '\0';
	476
	477	tmp = strchr(kbuf, ' ');
	478	if (!tmp) {
	479	rv = -EINVAL;
	480	goto out;
	481	}
	482	*tmp = '\0';
	483	tmp++;
	484
	485	if (!strcmp(kbuf, "add_node"))
	486	rv = do_add_node(tmp, count - (tmp - kbuf));
	487	else if (!strcmp(kbuf, "remove_node"))
	488	rv = do_remove_node(tmp);
610d9151 DB	489	else if (!strcmp(kbuf, "add_property"))
	490	rv = do_add_property(tmp, count - (tmp - kbuf));
	491	else if (!strcmp(kbuf, "remove_property"))
	492	rv = do_remove_property(tmp, count - (tmp - kbuf));
	493	else if (!strcmp(kbuf, "update_property"))
	494	rv = do_update_property(tmp, count - (tmp - kbuf));
1da177e4 LT	495	else
	496	rv = -EINVAL;
	497	out:
	498	kfree(kbuf);
	499	return rv ? rv : count;
	500	}
	501
5dfe4c96	502	static const struct file_operations ofdt_fops = {
1da177e4 LT	503	.write = ofdt_write
	504	};
	505
	506	/* create /proc/ppc64/ofdt write-only by root */
	507	static int proc_ppc64_create_ofdt(void)
	508	{
	509	struct proc_dir_entry *ent;
	510
e8222502	511	if (!machine_is(pseries))
1da177e4 LT	512	return 0;
	513
	514	ent = create_proc_entry("ppc64/ofdt", S_IWUSR, NULL);
	515	if (ent) {
1da177e4 LT	516	ent->data = NULL;
	517	ent->size = 0;
	518	ent->proc_fops = &ofdt_fops;
	519	}
	520
	521	return 0;
	522	}
	523	__initcall(proc_ppc64_create_ofdt);