[linux.git] / fs / sysfs / bin.c

/*
 * bin.c - binary file operations for sysfs.
 *
 * Copyright (c) 2003 Patrick Mochel
 * Copyright (c) 2003 Matthew Wilcox
 * Copyright (c) 2004 Silicon Graphics, Inc.
 */

#undef DEBUG

#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/slab.h>

#include <asm/uaccess.h>

#include "sysfs.h"

static int
fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
{
	struct bin_attribute * attr = to_bin_attr(dentry);
	struct kobject * kobj = to_kobj(dentry->d_parent);

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

	return attr->read(kobj, buffer, off, count);
}

static ssize_t
read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
{
	char *buffer = file->private_data;
	struct dentry *dentry = file->f_dentry;
	int size = dentry->d_inode->i_size;
	loff_t offs = *off;
	int ret;

	if (count > PAGE_SIZE)
		count = PAGE_SIZE;

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

	ret = fill_read(dentry, buffer, offs, count);
	if (ret < 0) 
		return ret;
	count = ret;

	if (copy_to_user(userbuf, buffer, count))
		return -EFAULT;

	pr_debug("offs = %lld, *off = %lld, count = %zd\n", offs, *off, count);

	*off = offs + count;

	return count;
}

static int
flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
{
	struct bin_attribute *attr = to_bin_attr(dentry);
	struct kobject *kobj = to_kobj(dentry->d_parent);

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

	return attr->write(kobj, buffer, offset, count);
}

static ssize_t write(struct file * file, const char __user * userbuf,
		     size_t count, loff_t * off)
{
	char *buffer = file->private_data;
	struct dentry *dentry = file->f_dentry;
	int size = dentry->d_inode->i_size;
	loff_t offs = *off;

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

	if (copy_from_user(buffer, userbuf, count))
		return -EFAULT;

	count = flush_write(dentry, buffer, offs, count);
	if (count > 0)
		*off = offs + count;
	return count;
}

static int mmap(struct file *file, struct vm_area_struct *vma)
{
	struct dentry *dentry = file->f_dentry;
	struct bin_attribute *attr = to_bin_attr(dentry);
	struct kobject *kobj = to_kobj(dentry->d_parent);

	if (!attr->mmap)
		return -EINVAL;

	return attr->mmap(kobj, attr, vma);
}

static int open(struct inode * inode, struct file * file)
{
	struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent);
	struct bin_attribute * attr = to_bin_attr(file->f_dentry);
	int error = -EINVAL;

	if (!kobj || !attr)
		goto Done;

	/* Grab the module reference for this attribute if we have one */
	error = -ENODEV;
	if (!try_module_get(attr->attr.owner)) 
		goto Done;

	error = -EACCES;
	if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
		goto Error;
	if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
		goto Error;

	error = -ENOMEM;
	file->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL);
	if (!file->private_data)
		goto Error;

	error = 0;
    goto Done;

 Error:
	module_put(attr->attr.owner);
 Done:
	if (error && kobj)
		kobject_put(kobj);
	return error;
}

static int release(struct inode * inode, struct file * file)
{
	struct kobject * kobj = to_kobj(file->f_dentry->d_parent);
	struct bin_attribute * attr = to_bin_attr(file->f_dentry);
	u8 * buffer = file->private_data;

	if (kobj) 
		kobject_put(kobj);
	module_put(attr->attr.owner);
	kfree(buffer);
	return 0;
}

const struct file_operations bin_fops = {
	.read		= read,
	.write		= write,
	.mmap		= mmap,
	.llseek		= generic_file_llseek,
	.open		= open,
	.release	= release,
};

/**
 *	sysfs_create_bin_file - create binary file for object.
 *	@kobj:	object.
 *	@attr:	attribute descriptor.
 *
 */

int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
	BUG_ON(!kobj || !kobj->dentry || !attr);

	return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
}


/**
 *	sysfs_remove_bin_file - remove binary file for object.
 *	@kobj:	object.
 *	@attr:	attribute descriptor.
 *
 */

int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
	sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
	return 0;
}

EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* bin.c - binary file operations for sysfs.
	3	*
	4	* Copyright (c) 2003 Patrick Mochel
	5	* Copyright (c) 2003 Matthew Wilcox
	6	* Copyright (c) 2004 Silicon Graphics, Inc.
	7	*/
	8
	9	#undef DEBUG
	10
	11	#include <linux/errno.h>
	12	#include <linux/fs.h>
	13	#include <linux/kobject.h>
	14	#include <linux/module.h>
	15	#include <linux/slab.h>
	16
	17	#include <asm/uaccess.h>
	18
	19	#include "sysfs.h"
	20
	21	static int
	22	fill_read(struct dentry dentry, char buffer, loff_t off, size_t count)
	23	{
	24	struct bin_attribute * attr = to_bin_attr(dentry);
	25	struct kobject * kobj = to_kobj(dentry->d_parent);
	26
	27	if (!attr->read)
c76d0abd	28	return -EIO;
1da177e4 LT	29
	30	return attr->read(kobj, buffer, off, count);
	31	}
	32
	33	static ssize_t
	34	read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
	35	{
	36	char *buffer = file->private_data;
	37	struct dentry *dentry = file->f_dentry;
	38	int size = dentry->d_inode->i_size;
	39	loff_t offs = *off;
	40	int ret;
	41
	42	if (count > PAGE_SIZE)
	43	count = PAGE_SIZE;
	44
	45	if (size) {
	46	if (offs > size)
	47	return 0;
	48	if (offs + count > size)
	49	count = size - offs;
	50	}
	51
	52	ret = fill_read(dentry, buffer, offs, count);
	53	if (ret < 0)
	54	return ret;
	55	count = ret;
	56
	57	if (copy_to_user(userbuf, buffer, count))
	58	return -EFAULT;
	59
	60	pr_debug("offs = %lld, off = %lld, count = %zd\n", offs, off, count);
	61
	62	*off = offs + count;
	63
	64	return count;
	65	}
	66
	67	static int
	68	flush_write(struct dentry dentry, char buffer, loff_t offset, size_t count)
	69	{
	70	struct bin_attribute *attr = to_bin_attr(dentry);
	71	struct kobject *kobj = to_kobj(dentry->d_parent);
	72
	73	if (!attr->write)
c76d0abd	74	return -EIO;
1da177e4 LT	75
	76	return attr->write(kobj, buffer, offset, count);
	77	}
	78
	79	static ssize_t write(struct file * file, const char __user * userbuf,
	80	size_t count, loff_t * off)
	81	{
	82	char *buffer = file->private_data;
	83	struct dentry *dentry = file->f_dentry;
	84	int size = dentry->d_inode->i_size;
	85	loff_t offs = *off;
	86
	87	if (count > PAGE_SIZE)
	88	count = PAGE_SIZE;
	89	if (size) {
	90	if (offs > size)
	91	return 0;
	92	if (offs + count > size)
	93	count = size - offs;
	94	}
	95
	96	if (copy_from_user(buffer, userbuf, count))
	97	return -EFAULT;
	98
	99	count = flush_write(dentry, buffer, offs, count);
	100	if (count > 0)
	101	*off = offs + count;
	102	return count;
	103	}
	104
	105	static int mmap(struct file file, struct vm_area_struct vma)
	106	{
	107	struct dentry *dentry = file->f_dentry;
	108	struct bin_attribute *attr = to_bin_attr(dentry);
	109	struct kobject *kobj = to_kobj(dentry->d_parent);
	110
	111	if (!attr->mmap)
	112	return -EINVAL;
	113
	114	return attr->mmap(kobj, attr, vma);
	115	}
	116
	117	static int open(struct inode * inode, struct file * file)
	118	{
	119	struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent);
	120	struct bin_attribute * attr = to_bin_attr(file->f_dentry);
	121	int error = -EINVAL;
	122
	123	if (!kobj \|\| !attr)
	124	goto Done;
	125
	126	/* Grab the module reference for this attribute if we have one */
	127	error = -ENODEV;
	128	if (!try_module_get(attr->attr.owner))
	129	goto Done;
	130
	131	error = -EACCES;
	132	if ((file->f_mode & FMODE_WRITE) && !(attr->write \|\| attr->mmap))
	133	goto Error;
	134	if ((file->f_mode & FMODE_READ) && !(attr->read \|\| attr->mmap))
	135	goto Error;
	136
	137	error = -ENOMEM;
	138	file->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL);
139	if (!file->private_data)
140	goto Error;
141
142	error = 0;
143	goto Done;
144
145	Error:
146	module_put(attr->attr.owner);
147	Done:
148	if (error && kobj)
149	kobject_put(kobj);
150	return error;
151	}
152
153	static int release(struct inode * inode, struct file * file)
154	{
155	struct kobject * kobj = to_kobj(file->f_dentry->d_parent);
156	struct bin_attribute * attr = to_bin_attr(file->f_dentry);
157	u8 * buffer = file->private_data;
158
159	if (kobj)
160	kobject_put(kobj);
161	module_put(attr->attr.owner);
162	kfree(buffer);
163	return 0;
164	}
165
4b6f5d20	166	const struct file_operations bin_fops = {
1da177e4 LT	167	.read = read,
	168	.write = write,
	169	.mmap = mmap,
	170	.llseek = generic_file_llseek,
	171	.open = open,
	172	.release = release,
	173	};
	174
	175	/**
	176	* sysfs_create_bin_file - create binary file for object.
	177	* @kobj: object.
	178	* @attr: attribute descriptor.
	179	*
	180	*/
	181
	182	int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
	183	{
	184	BUG_ON(!kobj \|\| !kobj->dentry \|\| !attr);
	185
	186	return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
	187	}
	188
	189
	190	/**
	191	* sysfs_remove_bin_file - remove binary file for object.
	192	* @kobj: object.
	193	* @attr: attribute descriptor.
	194	*
	195	*/
	196
	197	int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
	198	{
	199	sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
	200	return 0;
	201	}
	202
	203	EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
	204	EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);