[deliverable/linux.git] / fs / sysfs / file.c

/*
 * fs/sysfs/file.c - sysfs regular (text) file implementation
 *
 * Copyright (c) 2001-3 Patrick Mochel
 * Copyright (c) 2007 SUSE Linux Products GmbH
 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
 *
 * This file is released under the GPLv2.
 *
 * Please see Documentation/filesystems/sysfs.txt for more information.
 */

#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/kallsyms.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/seq_file.h>

#include "sysfs.h"
#include "../kernfs/kernfs-internal.h"

/*
 * Determine ktype->sysfs_ops for the given kernfs_node.  This function
 * must be called while holding an active reference.
 */
static const struct sysfs_ops *sysfs_file_ops(struct kernfs_node *kn)
{
	struct kobject *kobj = kn->parent->priv;

	if (kn->flags & KERNFS_LOCKDEP)
		lockdep_assert_held(kn);
	return kobj->ktype ? kobj->ktype->sysfs_ops : NULL;
}

/*
 * Reads on sysfs are handled through seq_file, which takes care of hairy
 * details like buffering and seeking.  The following function pipes
 * sysfs_ops->show() result through seq_file.
 */
static int sysfs_kf_seq_show(struct seq_file *sf, void *v)
{
	struct kernfs_open_file *of = sf->private;
	struct kobject *kobj = of->kn->parent->priv;
	const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
	ssize_t count;
	char *buf;

	/* acquire buffer and ensure that it's >= PAGE_SIZE and clear */
	count = seq_get_buf(sf, &buf);
	if (count < PAGE_SIZE) {
		seq_commit(sf, -1);
		return 0;
	}
	memset(buf, 0, PAGE_SIZE);

	/*
	 * Invoke show().  Control may reach here via seq file lseek even
	 * if @ops->show() isn't implemented.
	 */
	if (ops->show) {
		count = ops->show(kobj, of->kn->priv, buf);
		if (count < 0)
			return count;
	}

	/*
	 * The code works fine with PAGE_SIZE return but it's likely to
	 * indicate truncated result or overflow in normal use cases.
	 */
	if (count >= (ssize_t)PAGE_SIZE) {
		print_symbol("fill_read_buffer: %s returned bad count\n",
			(unsigned long)ops->show);
		/* Try to struggle along */
		count = PAGE_SIZE - 1;
	}
	seq_commit(sf, count);
	return 0;
}

static ssize_t sysfs_kf_bin_read(struct kernfs_open_file *of, char *buf,
				 size_t count, loff_t pos)
{
	struct bin_attribute *battr = of->kn->priv;
	struct kobject *kobj = of->kn->parent->priv;
	loff_t size = file_inode(of->file)->i_size;

	if (!count)
		return 0;

	if (size) {
		if (pos > size)
			return 0;
		if (pos + count > size)
			count = size - pos;
	}

	if (!battr->read)
		return -EIO;

	return battr->read(of->file, kobj, battr, buf, pos, count);
}

/* kernfs write callback for regular sysfs files */
static ssize_t sysfs_kf_write(struct kernfs_open_file *of, char *buf,
			      size_t count, loff_t pos)
{
	const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
	struct kobject *kobj = of->kn->parent->priv;

	if (!count)
		return 0;

	return ops->store(kobj, of->kn->priv, buf, count);
}

/* kernfs write callback for bin sysfs files */
static ssize_t sysfs_kf_bin_write(struct kernfs_open_file *of, char *buf,
				  size_t count, loff_t pos)
{
	struct bin_attribute *battr = of->kn->priv;
	struct kobject *kobj = of->kn->parent->priv;
	loff_t size = file_inode(of->file)->i_size;

	if (size) {
		if (size <= pos)
			return 0;
		count = min_t(ssize_t, count, size - pos);
	}
	if (!count)
		return 0;

	if (!battr->write)
		return -EIO;

	return battr->write(of->file, kobj, battr, buf, pos, count);
}

static int sysfs_kf_bin_mmap(struct kernfs_open_file *of,
			     struct vm_area_struct *vma)
{
	struct bin_attribute *battr = of->kn->priv;
	struct kobject *kobj = of->kn->parent->priv;

	return battr->mmap(of->file, kobj, battr, vma);
}

void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr)
{
	struct kernfs_node *kn = kobj->sd, *tmp;

	if (kn && dir)
		kn = kernfs_find_and_get(kn, dir);
	else
		kernfs_get(kn);

	if (kn && attr) {
		tmp = kernfs_find_and_get(kn, attr);
		kernfs_put(kn);
		kn = tmp;
	}

	if (kn) {
		kernfs_notify(kn);
		kernfs_put(kn);
	}
}
EXPORT_SYMBOL_GPL(sysfs_notify);

static const struct kernfs_ops sysfs_file_kfops_empty = {
};

static const struct kernfs_ops sysfs_file_kfops_ro = {
	.seq_show	= sysfs_kf_seq_show,
};

static const struct kernfs_ops sysfs_file_kfops_wo = {
	.write		= sysfs_kf_write,
};

static const struct kernfs_ops sysfs_file_kfops_rw = {
	.seq_show	= sysfs_kf_seq_show,
	.write		= sysfs_kf_write,
};

static const struct kernfs_ops sysfs_bin_kfops_ro = {
	.read		= sysfs_kf_bin_read,
};

static const struct kernfs_ops sysfs_bin_kfops_wo = {
	.write		= sysfs_kf_bin_write,
};

static const struct kernfs_ops sysfs_bin_kfops_rw = {
	.read		= sysfs_kf_bin_read,
	.write		= sysfs_kf_bin_write,
};

static const struct kernfs_ops sysfs_bin_kfops_mmap = {
	.read		= sysfs_kf_bin_read,
	.write		= sysfs_kf_bin_write,
	.mmap		= sysfs_kf_bin_mmap,
};

int sysfs_add_file_mode_ns(struct kernfs_node *parent,
			   const struct attribute *attr, bool is_bin,
			   umode_t mode, const void *ns)
{
	struct lock_class_key *key = NULL;
	const struct kernfs_ops *ops;
	struct kernfs_node *kn;
	loff_t size;

	if (!is_bin) {
		struct kobject *kobj = parent->priv;
		const struct sysfs_ops *sysfs_ops = kobj->ktype->sysfs_ops;

		/* every kobject with an attribute needs a ktype assigned */
		if (WARN(!sysfs_ops, KERN_ERR
			 "missing sysfs attribute operations for kobject: %s\n",
			 kobject_name(kobj)))
			return -EINVAL;

		if (sysfs_ops->show && sysfs_ops->store)
			ops = &sysfs_file_kfops_rw;
		else if (sysfs_ops->show)
			ops = &sysfs_file_kfops_ro;
		else if (sysfs_ops->store)
			ops = &sysfs_file_kfops_wo;
		else
			ops = &sysfs_file_kfops_empty;

		size = PAGE_SIZE;
	} else {
		struct bin_attribute *battr = (void *)attr;

		if (battr->mmap)
			ops = &sysfs_bin_kfops_mmap;
		else if (battr->read && battr->write)
			ops = &sysfs_bin_kfops_rw;
		else if (battr->read)
			ops = &sysfs_bin_kfops_ro;
		else if (battr->write)
			ops = &sysfs_bin_kfops_wo;
		else
			ops = &sysfs_file_kfops_empty;

		size = battr->size;
	}

#ifdef CONFIG_DEBUG_LOCK_ALLOC
	if (!attr->ignore_lockdep)
		key = attr->key ?: (struct lock_class_key *)&attr->skey;
#endif
	kn = __kernfs_create_file(parent, attr->name, mode, size, ops,
				  (void *)attr, ns, true, key);
	if (IS_ERR(kn)) {
		if (PTR_ERR(kn) == -EEXIST)
			sysfs_warn_dup(parent, attr->name);
		return PTR_ERR(kn);
	}
	return 0;
}

int sysfs_add_file(struct kernfs_node *parent, const struct attribute *attr,
		   bool is_bin)
{
	return sysfs_add_file_mode_ns(parent, attr, is_bin, attr->mode, NULL);
}

/**
 * sysfs_create_file_ns - create an attribute file for an object with custom ns
 * @kobj: object we're creating for
 * @attr: attribute descriptor
 * @ns: namespace the new file should belong to
 */
int sysfs_create_file_ns(struct kobject *kobj, const struct attribute *attr,
			 const void *ns)
{
	BUG_ON(!kobj || !kobj->sd || !attr);

	return sysfs_add_file_mode_ns(kobj->sd, attr, false, attr->mode, ns);

}
EXPORT_SYMBOL_GPL(sysfs_create_file_ns);

int sysfs_create_files(struct kobject *kobj, const struct attribute **ptr)
{
	int err = 0;
	int i;

	for (i = 0; ptr[i] && !err; i++)
		err = sysfs_create_file(kobj, ptr[i]);
	if (err)
		while (--i >= 0)
			sysfs_remove_file(kobj, ptr[i]);
	return err;
}
EXPORT_SYMBOL_GPL(sysfs_create_files);

/**
 * sysfs_add_file_to_group - add an attribute file to a pre-existing group.
 * @kobj: object we're acting for.
 * @attr: attribute descriptor.
 * @group: group name.
 */
int sysfs_add_file_to_group(struct kobject *kobj,
		const struct attribute *attr, const char *group)
{
	struct kernfs_node *parent;
	int error;

	if (group) {
		parent = kernfs_find_and_get(kobj->sd, group);
	} else {
		parent = kobj->sd;
		kernfs_get(parent);
	}

	if (!parent)
		return -ENOENT;

	error = sysfs_add_file(parent, attr, false);
	kernfs_put(parent);

	return error;
}
EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);

/**
 * sysfs_chmod_file - update the modified mode value on an object attribute.
 * @kobj: object we're acting for.
 * @attr: attribute descriptor.
 * @mode: file permissions.
 *
 */
int sysfs_chmod_file(struct kobject *kobj, const struct attribute *attr,
		     umode_t mode)
{
	struct kernfs_node *kn;
	struct iattr newattrs;
	int rc;

	kn = kernfs_find_and_get(kobj->sd, attr->name);
	if (!kn)
		return -ENOENT;

	newattrs.ia_mode = (mode & S_IALLUGO) | (kn->mode & ~S_IALLUGO);
	newattrs.ia_valid = ATTR_MODE;

	rc = kernfs_setattr(kn, &newattrs);

	kernfs_put(kn);
	return rc;
}
EXPORT_SYMBOL_GPL(sysfs_chmod_file);

/**
 * sysfs_remove_file_ns - remove an object attribute with a custom ns tag
 * @kobj: object we're acting for
 * @attr: attribute descriptor
 * @ns: namespace tag of the file to remove
 *
 * Hash the attribute name and namespace tag and kill the victim.
 */
void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
			  const void *ns)
{
	struct kernfs_node *parent = kobj->sd;

	kernfs_remove_by_name_ns(parent, attr->name, ns);
}
EXPORT_SYMBOL_GPL(sysfs_remove_file_ns);

/**
 * sysfs_remove_file_self - remove an object attribute from its own method
 * @kobj: object we're acting for
 * @attr: attribute descriptor
 *
 * See kernfs_remove_self() for details.
 */
bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr)
{
	struct kernfs_node *parent = kobj->sd;
	struct kernfs_node *kn;
	bool ret;

	kn = kernfs_find_and_get(parent, attr->name);
	if (WARN_ON_ONCE(!kn))
		return false;

	ret = kernfs_remove_self(kn);

	kernfs_put(kn);
	return ret;
}

void sysfs_remove_files(struct kobject *kobj, const struct attribute **ptr)
{
	int i;
	for (i = 0; ptr[i]; i++)
		sysfs_remove_file(kobj, ptr[i]);
}
EXPORT_SYMBOL_GPL(sysfs_remove_files);

/**
 * sysfs_remove_file_from_group - remove an attribute file from a group.
 * @kobj: object we're acting for.
 * @attr: attribute descriptor.
 * @group: group name.
 */
void sysfs_remove_file_from_group(struct kobject *kobj,
		const struct attribute *attr, const char *group)
{
	struct kernfs_node *parent;

	if (group) {
		parent = kernfs_find_and_get(kobj->sd, group);
	} else {
		parent = kobj->sd;
		kernfs_get(parent);
	}

	if (parent) {
		kernfs_remove_by_name(parent, attr->name);
		kernfs_put(parent);
	}
}
EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);

/**
 *	sysfs_create_bin_file - create binary file for object.
 *	@kobj:	object.
 *	@attr:	attribute descriptor.
 */
int sysfs_create_bin_file(struct kobject *kobj,
			  const struct bin_attribute *attr)
{
	BUG_ON(!kobj || !kobj->sd || !attr);

	return sysfs_add_file(kobj->sd, &attr->attr, true);
}
EXPORT_SYMBOL_GPL(sysfs_create_bin_file);

/**
 *	sysfs_remove_bin_file - remove binary file for object.
 *	@kobj:	object.
 *	@attr:	attribute descriptor.
 */
void sysfs_remove_bin_file(struct kobject *kobj,
			   const struct bin_attribute *attr)
{
	kernfs_remove_by_name(kobj->sd, attr->attr.name);
}
EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);
Commit	Line	Data
1da177e4	1	/*
6d66f5cd TH	2	* fs/sysfs/file.c - sysfs regular (text) file implementation
	3	*
	4	* Copyright (c) 2001-3 Patrick Mochel
	5	* Copyright (c) 2007 SUSE Linux Products GmbH
	6	* Copyright (c) 2007 Tejun Heo <teheo@suse.de>
	7	*
	8	* This file is released under the GPLv2.
	9	*
	10	* Please see Documentation/filesystems/sysfs.txt for more information.
1da177e4 LT	11	*/
	12
	13	#include <linux/module.h>
1da177e4	14	#include <linux/kobject.h>
815d2d50	15	#include <linux/kallsyms.h>
c6f87733	16	#include <linux/slab.h>
94bebf4d	17	#include <linux/list.h>
52e8c209	18	#include <linux/mutex.h>
13c589d5	19	#include <linux/seq_file.h>
1da177e4 LT	20
1da177e4 LT	21	#include "sysfs.h"
414985ae	22	#include "../kernfs/kernfs-internal.h"
f6acf8bb	23
375b611e	24	/*
324a56e1	25	* Determine ktype->sysfs_ops for the given kernfs_node. This function
375b611e TH	26	* must be called while holding an active reference.
375b611e TH	27	*/
324a56e1	28	static const struct sysfs_ops sysfs_file_ops(struct kernfs_node kn)
375b611e	29	{
adc5e8b5	30	struct kobject *kobj = kn->parent->priv;
375b611e	31
df23fc39	32	if (kn->flags & KERNFS_LOCKDEP)
324a56e1	33	lockdep_assert_held(kn);
375b611e TH	34	return kobj->ktype ? kobj->ktype->sysfs_ops : NULL;
	35	}
	36
13c589d5 TH	37	/*
	38	* Reads on sysfs are handled through seq_file, which takes care of hairy
	39	* details like buffering and seeking. The following function pipes
	40	* sysfs_ops->show() result through seq_file.
1da177e4	41	*/
c2b19daf	42	static int sysfs_kf_seq_show(struct seq_file sf, void v)
1da177e4	43	{
c525aadd	44	struct kernfs_open_file *of = sf->private;
adc5e8b5	45	struct kobject *kobj = of->kn->parent->priv;
324a56e1	46	const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
1da177e4	47	ssize_t count;
c2b19daf	48	char *buf;
1da177e4	49
f5c16f29	50	/* acquire buffer and ensure that it's >= PAGE_SIZE and clear */
13c589d5 TH	51	count = seq_get_buf(sf, &buf);
	52	if (count < PAGE_SIZE) {
	53	seq_commit(sf, -1);
	54	return 0;
	55	}
f5c16f29	56	memset(buf, 0, PAGE_SIZE);
1da177e4	57
13c589d5	58	/*
c2b19daf TH	59	* Invoke show(). Control may reach here via seq file lseek even
c2b19daf TH	60	* if @ops->show() isn't implemented.
13c589d5	61	*/
c2b19daf	62	if (ops->show) {
324a56e1	63	count = ops->show(kobj, of->kn->priv, buf);
c2b19daf TH	64	if (count < 0)
	65	return count;
	66	}
0ab66088	67
8118a859 MX	68	/*
	69	* The code works fine with PAGE_SIZE return but it's likely to
	70	* indicate truncated result or overflow in normal use cases.
	71	*/
815d2d50 AM	72	if (count >= (ssize_t)PAGE_SIZE) {
	73	print_symbol("fill_read_buffer: %s returned bad count\n",
	74	(unsigned long)ops->show);
	75	/* Try to struggle along */
	76	count = PAGE_SIZE - 1;
	77	}
13c589d5 TH	78	seq_commit(sf, count);
13c589d5 TH	79	return 0;
1da177e4 LT	80	}
1da177e4 LT	81
c525aadd	82	static ssize_t sysfs_kf_bin_read(struct kernfs_open_file of, char buf,
c2b19daf	83	size_t count, loff_t pos)
2f0c6b75	84	{
324a56e1	85	struct bin_attribute *battr = of->kn->priv;
adc5e8b5	86	struct kobject *kobj = of->kn->parent->priv;
c2b19daf	87	loff_t size = file_inode(of->file)->i_size;
2f0c6b75	88
c2b19daf	89	if (!count)
2f0c6b75 TH	90	return 0;
	91
	92	if (size) {
c2b19daf	93	if (pos > size)
2f0c6b75	94	return 0;
c2b19daf TH	95	if (pos + count > size)
c2b19daf TH	96	count = size - pos;
2f0c6b75 TH	97	}
2f0c6b75 TH	98
c2b19daf TH	99	if (!battr->read)
	100	return -EIO;
	101
	102	return battr->read(of->file, kobj, battr, buf, pos, count);
	103	}
	104
50b38ca0	105	/* kernfs write callback for regular sysfs files */
c525aadd	106	static ssize_t sysfs_kf_write(struct kernfs_open_file of, char buf,
50b38ca0	107	size_t count, loff_t pos)
1da177e4	108	{
324a56e1	109	const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
adc5e8b5	110	struct kobject *kobj = of->kn->parent->priv;
0ab66088	111
50b38ca0 TH	112	if (!count)
50b38ca0 TH	113	return 0;
0ab66088	114
324a56e1	115	return ops->store(kobj, of->kn->priv, buf, count);
50b38ca0	116	}
f9b9a621	117
50b38ca0	118	/* kernfs write callback for bin sysfs files */
c525aadd	119	static ssize_t sysfs_kf_bin_write(struct kernfs_open_file of, char buf,
50b38ca0 TH	120	size_t count, loff_t pos)
50b38ca0 TH	121	{
324a56e1	122	struct bin_attribute *battr = of->kn->priv;
adc5e8b5	123	struct kobject *kobj = of->kn->parent->priv;
50b38ca0	124	loff_t size = file_inode(of->file)->i_size;
f9b9a621	125
50b38ca0 TH	126	if (size) {
	127	if (size <= pos)
	128	return 0;
	129	count = min_t(ssize_t, count, size - pos);
f9b9a621	130	}
50b38ca0 TH	131	if (!count)
50b38ca0 TH	132	return 0;
0ab66088	133
50b38ca0 TH	134	if (!battr->write)
50b38ca0 TH	135	return -EIO;
1da177e4	136
50b38ca0	137	return battr->write(of->file, kobj, battr, buf, pos, count);
1da177e4 LT	138	}
1da177e4 LT	139
c525aadd	140	static int sysfs_kf_bin_mmap(struct kernfs_open_file *of,
fdbffaa4 TH	141	struct vm_area_struct *vma)
fdbffaa4 TH	142	{
324a56e1	143	struct bin_attribute *battr = of->kn->priv;
adc5e8b5	144	struct kobject *kobj = of->kn->parent->priv;
fdbffaa4	145
fdbffaa4 TH	146	return battr->mmap(of->file, kobj, battr, vma);
	147	}
	148
324a56e1	149	void sysfs_notify(struct kobject kobj, const char dir, const char *attr)
4508a7a7	150	{
324a56e1	151	struct kernfs_node kn = kobj->sd, tmp;
51225039	152
324a56e1 TH	153	if (kn && dir)
324a56e1 TH	154	kn = kernfs_find_and_get(kn, dir);
024f6471	155	else
324a56e1	156	kernfs_get(kn);
024f6471	157
324a56e1 TH	158	if (kn && attr) {
	159	tmp = kernfs_find_and_get(kn, attr);
	160	kernfs_put(kn);
	161	kn = tmp;
024f6471	162	}
51225039	163
324a56e1 TH	164	if (kn) {
	165	kernfs_notify(kn);
	166	kernfs_put(kn);
024f6471	167	}
4508a7a7 N	168	}
	169	EXPORT_SYMBOL_GPL(sysfs_notify);
	170
f6acf8bb TH	171	static const struct kernfs_ops sysfs_file_kfops_empty = {
	172	};
	173
	174	static const struct kernfs_ops sysfs_file_kfops_ro = {
	175	.seq_show = sysfs_kf_seq_show,
	176	};
	177
	178	static const struct kernfs_ops sysfs_file_kfops_wo = {
	179	.write = sysfs_kf_write,
	180	};
	181
	182	static const struct kernfs_ops sysfs_file_kfops_rw = {
	183	.seq_show = sysfs_kf_seq_show,
	184	.write = sysfs_kf_write,
	185	};
	186
	187	static const struct kernfs_ops sysfs_bin_kfops_ro = {
	188	.read = sysfs_kf_bin_read,
	189	};
	190
	191	static const struct kernfs_ops sysfs_bin_kfops_wo = {
	192	.write = sysfs_kf_bin_write,
	193	};
	194
	195	static const struct kernfs_ops sysfs_bin_kfops_rw = {
	196	.read = sysfs_kf_bin_read,
	197	.write = sysfs_kf_bin_write,
9b2db6e1 TH	198	};
	199
	200	static const struct kernfs_ops sysfs_bin_kfops_mmap = {
	201	.read = sysfs_kf_bin_read,
	202	.write = sysfs_kf_bin_write,
f6acf8bb TH	203	.mmap = sysfs_kf_bin_mmap,
	204	};
	205
324a56e1	206	int sysfs_add_file_mode_ns(struct kernfs_node *parent,
a7dc66df	207	const struct attribute *attr, bool is_bin,
496f7394	208	umode_t mode, const void *ns)
1da177e4	209	{
517e64f5	210	struct lock_class_key *key = NULL;
f6acf8bb	211	const struct kernfs_ops *ops;
324a56e1	212	struct kernfs_node *kn;
471bd7b7	213	loff_t size;
1da177e4	214
a7dc66df	215	if (!is_bin) {
324a56e1	216	struct kobject *kobj = parent->priv;
f6acf8bb TH	217	const struct sysfs_ops *sysfs_ops = kobj->ktype->sysfs_ops;
	218
	219	/* every kobject with an attribute needs a ktype assigned */
	220	if (WARN(!sysfs_ops, KERN_ERR
	221	"missing sysfs attribute operations for kobject: %s\n",
	222	kobject_name(kobj)))
	223	return -EINVAL;
	224
	225	if (sysfs_ops->show && sysfs_ops->store)
	226	ops = &sysfs_file_kfops_rw;
	227	else if (sysfs_ops->show)
	228	ops = &sysfs_file_kfops_ro;
	229	else if (sysfs_ops->store)
	230	ops = &sysfs_file_kfops_wo;
	231	else
	232	ops = &sysfs_file_kfops_empty;
471bd7b7 TH	233
471bd7b7 TH	234	size = PAGE_SIZE;
f6acf8bb TH	235	} else {
	236	struct bin_attribute battr = (void )attr;
	237
9b2db6e1 TH	238	if (battr->mmap)
	239	ops = &sysfs_bin_kfops_mmap;
	240	else if (battr->read && battr->write)
f6acf8bb TH	241	ops = &sysfs_bin_kfops_rw;
	242	else if (battr->read)
	243	ops = &sysfs_bin_kfops_ro;
	244	else if (battr->write)
	245	ops = &sysfs_bin_kfops_wo;
	246	else
	247	ops = &sysfs_file_kfops_empty;
471bd7b7 TH	248
471bd7b7 TH	249	size = battr->size;
f6acf8bb TH	250	}
f6acf8bb TH	251
517e64f5 TH	252	#ifdef CONFIG_DEBUG_LOCK_ALLOC
	253	if (!attr->ignore_lockdep)
	254	key = attr->key ?: (struct lock_class_key *)&attr->skey;
	255	#endif
2063d608 TH	256	kn = __kernfs_create_file(parent, attr->name, mode, size, ops,
2063d608 TH	257	(void *)attr, ns, true, key);
324a56e1 TH	258	if (IS_ERR(kn)) {
	259	if (PTR_ERR(kn) == -EEXIST)
	260	sysfs_warn_dup(parent, attr->name);
	261	return PTR_ERR(kn);
496f7394 TH	262	}
	263	return 0;
	264	}
	265
324a56e1	266	int sysfs_add_file(struct kernfs_node parent, const struct attribute attr,
a7dc66df	267	bool is_bin)
0f423895	268	{
324a56e1	269	return sysfs_add_file_mode_ns(parent, attr, is_bin, attr->mode, NULL);
0f423895 JB	270	}
0f423895 JB	271
1da177e4	272	/**
58292cbe TH	273	* sysfs_create_file_ns - create an attribute file for an object with custom ns
	274	* @kobj: object we're creating for
	275	* @attr: attribute descriptor
	276	* @ns: namespace the new file should belong to
1da177e4	277	*/
58292cbe TH	278	int sysfs_create_file_ns(struct kobject kobj, const struct attribute attr,
58292cbe TH	279	const void *ns)
1da177e4	280	{
608e266a	281	BUG_ON(!kobj \|\| !kobj->sd \|\| !attr);
1da177e4	282
a7dc66df	283	return sysfs_add_file_mode_ns(kobj->sd, attr, false, attr->mode, ns);
1da177e4 LT	284
1da177e4 LT	285	}
58292cbe	286	EXPORT_SYMBOL_GPL(sysfs_create_file_ns);
1da177e4	287
1c205ae1 AK	288	int sysfs_create_files(struct kobject kobj, const struct attribute *ptr)
	289	{
	290	int err = 0;
	291	int i;
	292
	293	for (i = 0; ptr[i] && !err; i++)
	294	err = sysfs_create_file(kobj, ptr[i]);
	295	if (err)
	296	while (--i >= 0)
	297	sysfs_remove_file(kobj, ptr[i]);
	298	return err;
	299	}
1b866757	300	EXPORT_SYMBOL_GPL(sysfs_create_files);
1da177e4	301
dfa87c82 AS	302	/**
	303	* sysfs_add_file_to_group - add an attribute file to a pre-existing group.
	304	* @kobj: object we're acting for.
	305	* @attr: attribute descriptor.
	306	* @group: group name.
	307	*/
	308	int sysfs_add_file_to_group(struct kobject *kobj,
	309	const struct attribute attr, const char group)
	310	{
324a56e1	311	struct kernfs_node *parent;
dfa87c82 AS	312	int error;
dfa87c82 AS	313
ccf73cf3	314	if (group) {
324a56e1	315	parent = kernfs_find_and_get(kobj->sd, group);
ccf73cf3	316	} else {
324a56e1 TH	317	parent = kobj->sd;
324a56e1 TH	318	kernfs_get(parent);
ccf73cf3	319	}
11f24fbd	320
324a56e1	321	if (!parent)
608e266a TH	322	return -ENOENT;
608e266a TH	323
324a56e1 TH	324	error = sysfs_add_file(parent, attr, false);
324a56e1 TH	325	kernfs_put(parent);
608e266a	326
dfa87c82 AS	327	return error;
	328	}
	329	EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
	330
31e5abe9 KS	331	/**
	332	* sysfs_chmod_file - update the modified mode value on an object attribute.
	333	* @kobj: object we're acting for.
	334	* @attr: attribute descriptor.
	335	* @mode: file permissions.
	336	*
	337	*/
49c19400	338	int sysfs_chmod_file(struct kobject kobj, const struct attribute attr,
48176a97	339	umode_t mode)
31e5abe9	340	{
324a56e1	341	struct kernfs_node *kn;
bc062b1b	342	struct iattr newattrs;
51225039 TH	343	int rc;
51225039 TH	344
324a56e1 TH	345	kn = kernfs_find_and_get(kobj->sd, attr->name);
324a56e1 TH	346	if (!kn)
5d60418e	347	return -ENOENT;
f88123ea	348
adc5e8b5	349	newattrs.ia_mode = (mode & S_IALLUGO) \| (kn->mode & ~S_IALLUGO);
4c6974f5	350	newattrs.ia_valid = ATTR_MODE;
f88123ea	351
324a56e1	352	rc = kernfs_setattr(kn, &newattrs);
5d60418e	353
324a56e1	354	kernfs_put(kn);
51225039	355	return rc;
31e5abe9 KS	356	}
	357	EXPORT_SYMBOL_GPL(sysfs_chmod_file);
	358
1da177e4	359	/**
58292cbe TH	360	* sysfs_remove_file_ns - remove an object attribute with a custom ns tag
	361	* @kobj: object we're acting for
	362	* @attr: attribute descriptor
	363	* @ns: namespace tag of the file to remove
1da177e4	364	*
58292cbe	365	* Hash the attribute name and namespace tag and kill the victim.
1da177e4	366	*/
58292cbe TH	367	void sysfs_remove_file_ns(struct kobject kobj, const struct attribute attr,
58292cbe TH	368	const void *ns)
1da177e4	369	{
324a56e1	370	struct kernfs_node *parent = kobj->sd;
487505c2	371
324a56e1	372	kernfs_remove_by_name_ns(parent, attr->name, ns);
1da177e4	373	}
58292cbe	374	EXPORT_SYMBOL_GPL(sysfs_remove_file_ns);
1da177e4	375
6b0afc2a TH	376	/**
	377	* sysfs_remove_file_self - remove an object attribute from its own method
	378	* @kobj: object we're acting for
	379	* @attr: attribute descriptor
	380	*
	381	* See kernfs_remove_self() for details.
	382	*/
	383	bool sysfs_remove_file_self(struct kobject kobj, const struct attribute attr)
	384	{
	385	struct kernfs_node *parent = kobj->sd;
	386	struct kernfs_node *kn;
	387	bool ret;
	388
	389	kn = kernfs_find_and_get(parent, attr->name);
	390	if (WARN_ON_ONCE(!kn))
	391	return false;
	392
	393	ret = kernfs_remove_self(kn);
	394
	395	kernfs_put(kn);
	396	return ret;
	397	}
	398
1b18dc2b	399	void sysfs_remove_files(struct kobject kobj, const struct attribute *ptr)
1c205ae1 AK	400	{
	401	int i;
	402	for (i = 0; ptr[i]; i++)
	403	sysfs_remove_file(kobj, ptr[i]);
	404	}
1b866757	405	EXPORT_SYMBOL_GPL(sysfs_remove_files);
1da177e4	406
dfa87c82 AS	407	/**
	408	* sysfs_remove_file_from_group - remove an attribute file from a group.
	409	* @kobj: object we're acting for.
	410	* @attr: attribute descriptor.
	411	* @group: group name.
	412	*/
	413	void sysfs_remove_file_from_group(struct kobject *kobj,
	414	const struct attribute attr, const char group)
	415	{
324a56e1	416	struct kernfs_node *parent;
dfa87c82	417
ccf73cf3	418	if (group) {
324a56e1	419	parent = kernfs_find_and_get(kobj->sd, group);
ccf73cf3	420	} else {
324a56e1 TH	421	parent = kobj->sd;
324a56e1 TH	422	kernfs_get(parent);
ccf73cf3 TH	423	}
ccf73cf3 TH	424
324a56e1 TH	425	if (parent) {
	426	kernfs_remove_by_name(parent, attr->name);
	427	kernfs_put(parent);
dfa87c82 AS	428	}
	429	}
	430	EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
	431
3124eb16 TH	432	/**
	433	* sysfs_create_bin_file - create binary file for object.
	434	* @kobj: object.
	435	* @attr: attribute descriptor.
	436	*/
	437	int sysfs_create_bin_file(struct kobject *kobj,
	438	const struct bin_attribute *attr)
	439	{
	440	BUG_ON(!kobj \|\| !kobj->sd \|\| !attr);
	441
a7dc66df	442	return sysfs_add_file(kobj->sd, &attr->attr, true);
3124eb16 TH	443	}
	444	EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
	445
	446	/**
	447	* sysfs_remove_bin_file - remove binary file for object.
	448	* @kobj: object.
	449	* @attr: attribute descriptor.
	450	*/
	451	void sysfs_remove_bin_file(struct kobject *kobj,
	452	const struct bin_attribute *attr)
	453	{
879f40d1	454	kernfs_remove_by_name(kobj->sd, attr->attr.name);
3124eb16 TH	455	}
3124eb16 TH	456	EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);