[net-next-2.6.git] / fs / sysfs / bin.c

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

#undef DEBUG

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

#include <asm/uaccess.h>

#include "sysfs.h"

/*
 * There's one bin_buffer for each open file.
 *
 * filp->private_data points to bin_buffer and
 * sysfs_dirent->s_bin_attr.buffers points to a the bin_buffer s
 * sysfs_dirent->s_bin_attr.buffers is protected by sysfs_bin_lock
 */
static DEFINE_MUTEX(sysfs_bin_lock);

struct bin_buffer {
	struct mutex			mutex;
	void				*buffer;
	int				mmapped;
	const struct vm_operations_struct *vm_ops;
	struct file			*file;
	struct hlist_node		list;
};

static int
fill_read(struct file *file, char *buffer, loff_t off, size_t count)
{
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
	int rc;

	/* need attr_sd for attr, its parent for kobj */
	if (!sysfs_get_active(attr_sd))
		return -ENODEV;

	rc = -EIO;
	if (attr->read)
		rc = attr->read(file, kobj, attr, buffer, off, count);

	sysfs_put_active(attr_sd);

	return rc;
}

static ssize_t
read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
{
	struct bin_buffer *bb = file->private_data;
	int size = file->f_path.dentry->d_inode->i_size;
	loff_t offs = *off;
	int count = min_t(size_t, bytes, PAGE_SIZE);
	char *temp;

	if (!bytes)
		return 0;

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

	temp = kmalloc(count, GFP_KERNEL);
	if (!temp)
		return -ENOMEM;

	mutex_lock(&bb->mutex);

	count = fill_read(file, bb->buffer, offs, count);
	if (count < 0) {
		mutex_unlock(&bb->mutex);
		goto out_free;
	}

	memcpy(temp, bb->buffer, count);

	mutex_unlock(&bb->mutex);

	if (copy_to_user(userbuf, temp, count)) {
		count = -EFAULT;
		goto out_free;
	}

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

	*off = offs + count;

 out_free:
	kfree(temp);
	return count;
}

static int
flush_write(struct file *file, char *buffer, loff_t offset, size_t count)
{
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
	int rc;

	/* need attr_sd for attr, its parent for kobj */
	if (!sysfs_get_active(attr_sd))
		return -ENODEV;

	rc = -EIO;
	if (attr->write)
		rc = attr->write(file, kobj, attr, buffer, offset, count);

	sysfs_put_active(attr_sd);

	return rc;
}

static ssize_t write(struct file *file, const char __user *userbuf,
		     size_t bytes, loff_t *off)
{
	struct bin_buffer *bb = file->private_data;
	int size = file->f_path.dentry->d_inode->i_size;
	loff_t offs = *off;
	int count = min_t(size_t, bytes, PAGE_SIZE);
	char *temp;

	if (!bytes)
		return 0;

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

	temp = memdup_user(userbuf, count);
	if (IS_ERR(temp))
		return PTR_ERR(temp);

	mutex_lock(&bb->mutex);

	memcpy(bb->buffer, temp, count);

	count = flush_write(file, bb->buffer, offs, count);
	mutex_unlock(&bb->mutex);

	if (count > 0)
		*off = offs + count;

	kfree(temp);
	return count;
}

static void bin_vma_open(struct vm_area_struct *vma)
{
	struct file *file = vma->vm_file;
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;

	if (!bb->vm_ops)
		return;

	if (!sysfs_get_active(attr_sd))
		return;

	if (bb->vm_ops->open)
		bb->vm_ops->open(vma);

	sysfs_put_active(attr_sd);
}

static int bin_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct file *file = vma->vm_file;
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	int ret;

	if (!bb->vm_ops)
		return VM_FAULT_SIGBUS;

	if (!sysfs_get_active(attr_sd))
		return VM_FAULT_SIGBUS;

	ret = VM_FAULT_SIGBUS;
	if (bb->vm_ops->fault)
		ret = bb->vm_ops->fault(vma, vmf);

	sysfs_put_active(attr_sd);
	return ret;
}

static int bin_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct file *file = vma->vm_file;
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	int ret;

	if (!bb->vm_ops)
		return VM_FAULT_SIGBUS;

	if (!sysfs_get_active(attr_sd))
		return VM_FAULT_SIGBUS;

	ret = 0;
	if (bb->vm_ops->page_mkwrite)
		ret = bb->vm_ops->page_mkwrite(vma, vmf);

	sysfs_put_active(attr_sd);
	return ret;
}

static int bin_access(struct vm_area_struct *vma, unsigned long addr,
		  void *buf, int len, int write)
{
	struct file *file = vma->vm_file;
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	int ret;

	if (!bb->vm_ops)
		return -EINVAL;

	if (!sysfs_get_active(attr_sd))
		return -EINVAL;

	ret = -EINVAL;
	if (bb->vm_ops->access)
		ret = bb->vm_ops->access(vma, addr, buf, len, write);

	sysfs_put_active(attr_sd);
	return ret;
}

#ifdef CONFIG_NUMA
static int bin_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
{
	struct file *file = vma->vm_file;
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	int ret;

	if (!bb->vm_ops)
		return 0;

	if (!sysfs_get_active(attr_sd))
		return -EINVAL;

	ret = 0;
	if (bb->vm_ops->set_policy)
		ret = bb->vm_ops->set_policy(vma, new);

	sysfs_put_active(attr_sd);
	return ret;
}

static struct mempolicy *bin_get_policy(struct vm_area_struct *vma,
					unsigned long addr)
{
	struct file *file = vma->vm_file;
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	struct mempolicy *pol;

	if (!bb->vm_ops)
		return vma->vm_policy;

	if (!sysfs_get_active(attr_sd))
		return vma->vm_policy;

	pol = vma->vm_policy;
	if (bb->vm_ops->get_policy)
		pol = bb->vm_ops->get_policy(vma, addr);

	sysfs_put_active(attr_sd);
	return pol;
}

static int bin_migrate(struct vm_area_struct *vma, const nodemask_t *from,
			const nodemask_t *to, unsigned long flags)
{
	struct file *file = vma->vm_file;
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	int ret;

	if (!bb->vm_ops)
		return 0;

	if (!sysfs_get_active(attr_sd))
		return 0;

	ret = 0;
	if (bb->vm_ops->migrate)
		ret = bb->vm_ops->migrate(vma, from, to, flags);

	sysfs_put_active(attr_sd);
	return ret;
}
#endif

static const struct vm_operations_struct bin_vm_ops = {
	.open		= bin_vma_open,
	.fault		= bin_fault,
	.page_mkwrite	= bin_page_mkwrite,
	.access		= bin_access,
#ifdef CONFIG_NUMA
	.set_policy	= bin_set_policy,
	.get_policy	= bin_get_policy,
	.migrate	= bin_migrate,
#endif
};

static int mmap(struct file *file, struct vm_area_struct *vma)
{
	struct bin_buffer *bb = file->private_data;
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
	int rc;

	mutex_lock(&bb->mutex);

	/* need attr_sd for attr, its parent for kobj */
	rc = -ENODEV;
	if (!sysfs_get_active(attr_sd))
		goto out_unlock;

	rc = -EINVAL;
	if (!attr->mmap)
		goto out_put;

	rc = attr->mmap(file, kobj, attr, vma);
	if (rc)
		goto out_put;

	/*
	 * PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
	 * to satisfy versions of X which crash if the mmap fails: that
	 * substitutes a new vm_file, and we don't then want bin_vm_ops.
	 */
	if (vma->vm_file != file)
		goto out_put;

	rc = -EINVAL;
	if (bb->mmapped && bb->vm_ops != vma->vm_ops)
		goto out_put;

	/*
	 * It is not possible to successfully wrap close.
	 * So error if someone is trying to use close.
	 */
	rc = -EINVAL;
	if (vma->vm_ops && vma->vm_ops->close)
		goto out_put;

	rc = 0;
	bb->mmapped = 1;
	bb->vm_ops = vma->vm_ops;
	vma->vm_ops = &bin_vm_ops;
out_put:
	sysfs_put_active(attr_sd);
out_unlock:
	mutex_unlock(&bb->mutex);

	return rc;
}

static int open(struct inode * inode, struct file * file)
{
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
	struct bin_buffer *bb = NULL;
	int error;

	/* binary file operations requires both @sd and its parent */
	if (!sysfs_get_active(attr_sd))
		return -ENODEV;

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

	error = -ENOMEM;
	bb = kzalloc(sizeof(*bb), GFP_KERNEL);
	if (!bb)
		goto err_out;

	bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
	if (!bb->buffer)
		goto err_out;

	mutex_init(&bb->mutex);
	bb->file = file;
	file->private_data = bb;

	mutex_lock(&sysfs_bin_lock);
	hlist_add_head(&bb->list, &attr_sd->s_bin_attr.buffers);
	mutex_unlock(&sysfs_bin_lock);

	/* open succeeded, put active references */
	sysfs_put_active(attr_sd);
	return 0;

 err_out:
	sysfs_put_active(attr_sd);
	kfree(bb);
	return error;
}

static int release(struct inode * inode, struct file * file)
{
	struct bin_buffer *bb = file->private_data;

	mutex_lock(&sysfs_bin_lock);
	hlist_del(&bb->list);
	mutex_unlock(&sysfs_bin_lock);

	kfree(bb->buffer);
	kfree(bb);
	return 0;
}

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


void unmap_bin_file(struct sysfs_dirent *attr_sd)
{
	struct bin_buffer *bb;
	struct hlist_node *tmp;

	if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR)
		return;

	mutex_lock(&sysfs_bin_lock);

	hlist_for_each_entry(bb, tmp, &attr_sd->s_bin_attr.buffers, list) {
		struct inode *inode = bb->file->f_path.dentry->d_inode;

		unmap_mapping_range(inode->i_mapping, 0, 0, 1);
	}

	mutex_unlock(&sysfs_bin_lock);
}

/**
 *	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, SYSFS_KOBJ_BIN_ATTR);
}


/**
 *	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)
{
	sysfs_hash_and_remove(kobj->sd, NULL, attr->attr.name);
}

EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);
Commit	Line	Data
1da177e4	1	/*
6d66f5cd	2	* fs/sysfs/bin.c - sysfs binary file implementation
1da177e4 LT	3	*
	4	* Copyright (c) 2003 Patrick Mochel
	5	* Copyright (c) 2003 Matthew Wilcox
	6	* Copyright (c) 2004 Silicon Graphics, Inc.
6d66f5cd TH	7	* Copyright (c) 2007 SUSE Linux Products GmbH
	8	* Copyright (c) 2007 Tejun Heo <teheo@suse.de>
	9	*
	10	* This file is released under the GPLv2.
	11	*
	12	* Please see Documentation/filesystems/sysfs.txt for more information.
1da177e4 LT	13	*/
	14
	15	#undef DEBUG
	16
	17	#include <linux/errno.h>
	18	#include <linux/fs.h>
995982ca	19	#include <linux/kernel.h>
1da177e4 LT	20	#include <linux/kobject.h>
	21	#include <linux/module.h>
	22	#include <linux/slab.h>
869512ab	23	#include <linux/mutex.h>
e0edd3c6	24	#include <linux/mm.h>
1da177e4 LT	25
	26	#include <asm/uaccess.h>
	27
	28	#include "sysfs.h"
	29
e0edd3c6 EB	30	/*
	31	* There's one bin_buffer for each open file.
	32	*
	33	* filp->private_data points to bin_buffer and
	34	* sysfs_dirent->s_bin_attr.buffers points to a the bin_buffer s
	35	* sysfs_dirent->s_bin_attr.buffers is protected by sysfs_bin_lock
	36	*/
	37	static DEFINE_MUTEX(sysfs_bin_lock);
	38
eb361653	39	struct bin_buffer {
e0edd3c6 EB	40	struct mutex mutex;
	41	void *buffer;
	42	int mmapped;
f0f37e2f	43	const struct vm_operations_struct *vm_ops;
e0edd3c6 EB	44	struct file *file;
e0edd3c6 EB	45	struct hlist_node list;
eb361653 TH	46	};
eb361653 TH	47
1da177e4	48	static int
2c3c8bea	49	fill_read(struct file file, char buffer, loff_t off, size_t count)
1da177e4	50	{
2c3c8bea	51	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 TH	52	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	53	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
0ab66088 TH	54	int rc;
	55
	56	/* need attr_sd for attr, its parent for kobj */
e72ceb8c	57	if (!sysfs_get_active(attr_sd))
0ab66088	58	return -ENODEV;
1da177e4	59
0ab66088 TH	60	rc = -EIO;
0ab66088 TH	61	if (attr->read)
2c3c8bea	62	rc = attr->read(file, kobj, attr, buffer, off, count);
1da177e4	63
e72ceb8c	64	sysfs_put_active(attr_sd);
0ab66088 TH	65
0ab66088 TH	66	return rc;
1da177e4 LT	67	}
	68
	69	static ssize_t
93e3cd82	70	read(struct file file, char __user userbuf, size_t bytes, loff_t *off)
1da177e4	71	{
eb361653	72	struct bin_buffer *bb = file->private_data;
2c3c8bea	73	int size = file->f_path.dentry->d_inode->i_size;
1da177e4	74	loff_t offs = *off;
93e3cd82	75	int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5	76	char *temp;
1da177e4	77
4503efd0 GKH	78	if (!bytes)
	79	return 0;
	80
1da177e4 LT	81	if (size) {
	82	if (offs > size)
	83	return 0;
	84	if (offs + count > size)
	85	count = size - offs;
	86	}
	87
b31ca3f5 NP	88	temp = kmalloc(count, GFP_KERNEL);
	89	if (!temp)
	90	return -ENOMEM;
	91
eb361653 TH	92	mutex_lock(&bb->mutex);
eb361653 TH	93
2c3c8bea	94	count = fill_read(file, bb->buffer, offs, count);
b31ca3f5 NP	95	if (count < 0) {
	96	mutex_unlock(&bb->mutex);
	97	goto out_free;
	98	}
1da177e4	99
b31ca3f5 NP	100	memcpy(temp, bb->buffer, count);
	101
	102	mutex_unlock(&bb->mutex);
	103
	104	if (copy_to_user(userbuf, temp, count)) {
eb361653	105	count = -EFAULT;
b31ca3f5	106	goto out_free;
eb361653	107	}
1da177e4	108
93e3cd82	109	pr_debug("offs = %lld, off = %lld, count = %d\n", offs, off, count);
1da177e4 LT	110
	111	*off = offs + count;
	112
b31ca3f5 NP	113	out_free:
b31ca3f5 NP	114	kfree(temp);
1da177e4 LT	115	return count;
	116	}
	117
	118	static int
2c3c8bea	119	flush_write(struct file file, char buffer, loff_t offset, size_t count)
1da177e4	120	{
2c3c8bea	121	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 TH	122	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	123	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
0ab66088 TH	124	int rc;
	125
	126	/* need attr_sd for attr, its parent for kobj */
e72ceb8c	127	if (!sysfs_get_active(attr_sd))
0ab66088	128	return -ENODEV;
1da177e4	129
0ab66088 TH	130	rc = -EIO;
0ab66088 TH	131	if (attr->write)
2c3c8bea	132	rc = attr->write(file, kobj, attr, buffer, offset, count);
1da177e4	133
e72ceb8c	134	sysfs_put_active(attr_sd);
0ab66088 TH	135
0ab66088 TH	136	return rc;
1da177e4 LT	137	}
1da177e4 LT	138
93e3cd82 TH	139	static ssize_t write(struct file file, const char __user userbuf,
93e3cd82 TH	140	size_t bytes, loff_t *off)
1da177e4	141	{
eb361653	142	struct bin_buffer *bb = file->private_data;
2c3c8bea	143	int size = file->f_path.dentry->d_inode->i_size;
1da177e4	144	loff_t offs = *off;
93e3cd82	145	int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5	146	char *temp;
1da177e4	147
4503efd0 GKH	148	if (!bytes)
	149	return 0;
	150
1da177e4 LT	151	if (size) {
	152	if (offs > size)
	153	return 0;
	154	if (offs + count > size)
	155	count = size - offs;
	156	}
	157
1c8542c7 LZ	158	temp = memdup_user(userbuf, count);
	159	if (IS_ERR(temp))
	160	return PTR_ERR(temp);
1da177e4	161
b31ca3f5 NP	162	mutex_lock(&bb->mutex);
	163
	164	memcpy(bb->buffer, temp, count);
	165
2c3c8bea	166	count = flush_write(file, bb->buffer, offs, count);
b31ca3f5 NP	167	mutex_unlock(&bb->mutex);
b31ca3f5 NP	168
1da177e4 LT	169	if (count > 0)
1da177e4 LT	170	*off = offs + count;
eb361653	171
d5ce5b40	172	kfree(temp);
1da177e4 LT	173	return count;
	174	}
	175
e0edd3c6 EB	176	static void bin_vma_open(struct vm_area_struct *vma)
	177	{
	178	struct file *file = vma->vm_file;
	179	struct bin_buffer *bb = file->private_data;
	180	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	181
38f49a51	182	if (!bb->vm_ops)
e0edd3c6 EB	183	return;
e0edd3c6 EB	184
e72ceb8c	185	if (!sysfs_get_active(attr_sd))
e0edd3c6 EB	186	return;
e0edd3c6 EB	187
38f49a51 EB	188	if (bb->vm_ops->open)
38f49a51 EB	189	bb->vm_ops->open(vma);
e0edd3c6	190
e72ceb8c	191	sysfs_put_active(attr_sd);
e0edd3c6 EB	192	}
e0edd3c6 EB	193
e0edd3c6 EB	194	static int bin_fault(struct vm_area_struct vma, struct vm_fault vmf)
	195	{
	196	struct file *file = vma->vm_file;
	197	struct bin_buffer *bb = file->private_data;
	198	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	199	int ret;
	200
38f49a51	201	if (!bb->vm_ops)
e0edd3c6 EB	202	return VM_FAULT_SIGBUS;
e0edd3c6 EB	203
e72ceb8c	204	if (!sysfs_get_active(attr_sd))
e0edd3c6 EB	205	return VM_FAULT_SIGBUS;
e0edd3c6 EB	206
38f49a51 EB	207	ret = VM_FAULT_SIGBUS;
	208	if (bb->vm_ops->fault)
	209	ret = bb->vm_ops->fault(vma, vmf);
e0edd3c6	210
e72ceb8c	211	sysfs_put_active(attr_sd);
e0edd3c6 EB	212	return ret;
	213	}
	214
851a039c	215	static int bin_page_mkwrite(struct vm_area_struct vma, struct vm_fault vmf)
e0edd3c6 EB	216	{
	217	struct file *file = vma->vm_file;
	218	struct bin_buffer *bb = file->private_data;
	219	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	220	int ret;
	221
095160ae	222	if (!bb->vm_ops)
851a039c	223	return VM_FAULT_SIGBUS;
e0edd3c6	224
e72ceb8c	225	if (!sysfs_get_active(attr_sd))
851a039c	226	return VM_FAULT_SIGBUS;
e0edd3c6	227
38f49a51 EB	228	ret = 0;
	229	if (bb->vm_ops->page_mkwrite)
	230	ret = bb->vm_ops->page_mkwrite(vma, vmf);
e0edd3c6	231
e72ceb8c	232	sysfs_put_active(attr_sd);
e0edd3c6 EB	233	return ret;
	234	}
	235
	236	static int bin_access(struct vm_area_struct *vma, unsigned long addr,
	237	void *buf, int len, int write)
	238	{
	239	struct file *file = vma->vm_file;
	240	struct bin_buffer *bb = file->private_data;
	241	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	242	int ret;
	243
38f49a51	244	if (!bb->vm_ops)
e0edd3c6 EB	245	return -EINVAL;
e0edd3c6 EB	246
e72ceb8c	247	if (!sysfs_get_active(attr_sd))
e0edd3c6 EB	248	return -EINVAL;
e0edd3c6 EB	249
38f49a51 EB	250	ret = -EINVAL;
	251	if (bb->vm_ops->access)
	252	ret = bb->vm_ops->access(vma, addr, buf, len, write);
e0edd3c6	253
e72ceb8c	254	sysfs_put_active(attr_sd);
e0edd3c6 EB	255	return ret;
	256	}
	257
095160ae HD	258	#ifdef CONFIG_NUMA
	259	static int bin_set_policy(struct vm_area_struct vma, struct mempolicy new)
	260	{
	261	struct file *file = vma->vm_file;
	262	struct bin_buffer *bb = file->private_data;
	263	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	264	int ret;
	265
38f49a51	266	if (!bb->vm_ops)
095160ae HD	267	return 0;
095160ae HD	268
e72ceb8c	269	if (!sysfs_get_active(attr_sd))
095160ae HD	270	return -EINVAL;
095160ae HD	271
38f49a51 EB	272	ret = 0;
	273	if (bb->vm_ops->set_policy)
	274	ret = bb->vm_ops->set_policy(vma, new);
095160ae	275
e72ceb8c	276	sysfs_put_active(attr_sd);
095160ae HD	277	return ret;
	278	}
	279
	280	static struct mempolicy bin_get_policy(struct vm_area_struct vma,
	281	unsigned long addr)
	282	{
	283	struct file *file = vma->vm_file;
	284	struct bin_buffer *bb = file->private_data;
	285	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	286	struct mempolicy *pol;
	287
38f49a51	288	if (!bb->vm_ops)
095160ae HD	289	return vma->vm_policy;
095160ae HD	290
e72ceb8c	291	if (!sysfs_get_active(attr_sd))
095160ae HD	292	return vma->vm_policy;
095160ae HD	293
38f49a51 EB	294	pol = vma->vm_policy;
	295	if (bb->vm_ops->get_policy)
	296	pol = bb->vm_ops->get_policy(vma, addr);
095160ae	297
e72ceb8c	298	sysfs_put_active(attr_sd);
095160ae HD	299	return pol;
	300	}
	301
	302	static int bin_migrate(struct vm_area_struct vma, const nodemask_t from,
	303	const nodemask_t *to, unsigned long flags)
	304	{
	305	struct file *file = vma->vm_file;
	306	struct bin_buffer *bb = file->private_data;
	307	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	308	int ret;
	309
38f49a51	310	if (!bb->vm_ops)
095160ae HD	311	return 0;
095160ae HD	312
e72ceb8c	313	if (!sysfs_get_active(attr_sd))
095160ae HD	314	return 0;
095160ae HD	315
38f49a51 EB	316	ret = 0;
	317	if (bb->vm_ops->migrate)
	318	ret = bb->vm_ops->migrate(vma, from, to, flags);
095160ae	319
e72ceb8c	320	sysfs_put_active(attr_sd);
095160ae HD	321	return ret;
	322	}
	323	#endif
	324
f0f37e2f	325	static const struct vm_operations_struct bin_vm_ops = {
e0edd3c6	326	.open = bin_vma_open,
e0edd3c6 EB	327	.fault = bin_fault,
	328	.page_mkwrite = bin_page_mkwrite,
	329	.access = bin_access,
095160ae HD	330	#ifdef CONFIG_NUMA
	331	.set_policy = bin_set_policy,
	332	.get_policy = bin_get_policy,
	333	.migrate = bin_migrate,
	334	#endif
e0edd3c6 EB	335	};
e0edd3c6 EB	336
1da177e4 LT	337	static int mmap(struct file file, struct vm_area_struct vma)
1da177e4 LT	338	{
eb361653	339	struct bin_buffer *bb = file->private_data;
3e519038	340	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 TH	341	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	342	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
eb361653	343	int rc;
1da177e4	344
eb361653	345	mutex_lock(&bb->mutex);
0ab66088 TH	346
0ab66088 TH	347	/* need attr_sd for attr, its parent for kobj */
e0edd3c6	348	rc = -ENODEV;
e72ceb8c	349	if (!sysfs_get_active(attr_sd))
e0edd3c6	350	goto out_unlock;
0ab66088 TH	351
0ab66088 TH	352	rc = -EINVAL;
e0edd3c6 EB	353	if (!attr->mmap)
e0edd3c6 EB	354	goto out_put;
0ab66088	355
2c3c8bea	356	rc = attr->mmap(file, kobj, attr, vma);
e0edd3c6 EB	357	if (rc)
e0edd3c6 EB	358	goto out_put;
0ab66088	359
095160ae HD	360	/*
	361	* PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
	362	* to satisfy versions of X which crash if the mmap fails: that
	363	* substitutes a new vm_file, and we don't then want bin_vm_ops.
	364	*/
	365	if (vma->vm_file != file)
e0edd3c6 EB	366	goto out_put;
e0edd3c6 EB	367
e0edd3c6	368	rc = -EINVAL;
095160ae	369	if (bb->mmapped && bb->vm_ops != vma->vm_ops)
e0edd3c6	370	goto out_put;
e0edd3c6	371
a6849fa1 EB	372	/*
	373	* It is not possible to successfully wrap close.
	374	* So error if someone is trying to use close.
	375	*/
	376	rc = -EINVAL;
	377	if (vma->vm_ops && vma->vm_ops->close)
	378	goto out_put;
	379
e0edd3c6 EB	380	rc = 0;
e0edd3c6 EB	381	bb->mmapped = 1;
095160ae HD	382	bb->vm_ops = vma->vm_ops;
095160ae HD	383	vma->vm_ops = &bin_vm_ops;
e0edd3c6	384	out_put:
e72ceb8c	385	sysfs_put_active(attr_sd);
e0edd3c6	386	out_unlock:
eb361653 TH	387	mutex_unlock(&bb->mutex);
	388
	389	return rc;
1da177e4 LT	390	}
	391
	392	static int open(struct inode * inode, struct file * file)
	393	{
3e519038	394	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61	395	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
eb361653	396	struct bin_buffer *bb = NULL;
0ab66088	397	int error;
1da177e4	398
078ce640	399	/* binary file operations requires both @sd and its parent */
e72ceb8c	400	if (!sysfs_get_active(attr_sd))
0ab66088	401	return -ENODEV;
1da177e4	402
1da177e4 LT	403	error = -EACCES;
1da177e4 LT	404	if ((file->f_mode & FMODE_WRITE) && !(attr->write \|\| attr->mmap))
7b595756	405	goto err_out;
1da177e4	406	if ((file->f_mode & FMODE_READ) && !(attr->read \|\| attr->mmap))
7b595756	407	goto err_out;
1da177e4 LT	408
1da177e4 LT	409	error = -ENOMEM;
eb361653 TH	410	bb = kzalloc(sizeof(*bb), GFP_KERNEL);
eb361653 TH	411	if (!bb)
7b595756	412	goto err_out;
1da177e4	413
eb361653 TH	414	bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
eb361653 TH	415	if (!bb->buffer)
7b595756	416	goto err_out;
eb361653 TH	417
eb361653 TH	418	mutex_init(&bb->mutex);
e0edd3c6	419	bb->file = file;
eb361653 TH	420	file->private_data = bb;
eb361653 TH	421
e0edd3c6 EB	422	mutex_lock(&sysfs_bin_lock);
	423	hlist_add_head(&bb->list, &attr_sd->s_bin_attr.buffers);
	424	mutex_unlock(&sysfs_bin_lock);
	425
078ce640	426	/* open succeeded, put active references */
e72ceb8c	427	sysfs_put_active(attr_sd);
0ab66088	428	return 0;
1da177e4	429
7b595756	430	err_out:
e72ceb8c	431	sysfs_put_active(attr_sd);
0ab66088	432	kfree(bb);
1da177e4 LT	433	return error;
	434	}
	435
	436	static int release(struct inode * inode, struct file * file)
	437	{
eb361653	438	struct bin_buffer *bb = file->private_data;
1da177e4	439
e0edd3c6 EB	440	mutex_lock(&sysfs_bin_lock);
	441	hlist_del(&bb->list);
	442	mutex_unlock(&sysfs_bin_lock);
	443
eb361653 TH	444	kfree(bb->buffer);
eb361653 TH	445	kfree(bb);
1da177e4 LT	446	return 0;
	447	}
	448
4b6f5d20	449	const struct file_operations bin_fops = {
1da177e4 LT	450	.read = read,
	451	.write = write,
	452	.mmap = mmap,
	453	.llseek = generic_file_llseek,
	454	.open = open,
	455	.release = release,
	456	};
	457
e0edd3c6 EB	458
	459	void unmap_bin_file(struct sysfs_dirent *attr_sd)
	460	{
	461	struct bin_buffer *bb;
	462	struct hlist_node *tmp;
	463
	464	if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR)
	465	return;
	466
	467	mutex_lock(&sysfs_bin_lock);
	468
	469	hlist_for_each_entry(bb, tmp, &attr_sd->s_bin_attr.buffers, list) {
	470	struct inode *inode = bb->file->f_path.dentry->d_inode;
	471
	472	unmap_mapping_range(inode->i_mapping, 0, 0, 1);
	473	}
	474
	475	mutex_unlock(&sysfs_bin_lock);
	476	}
	477
1da177e4 LT	478	/**
	479	* sysfs_create_bin_file - create binary file for object.
	480	* @kobj: object.
	481	* @attr: attribute descriptor.
1da177e4 LT	482	*/
1da177e4 LT	483
66ecb92b PC	484	int sysfs_create_bin_file(struct kobject *kobj,
66ecb92b PC	485	const struct bin_attribute *attr)
1da177e4	486	{
608e266a	487	BUG_ON(!kobj \|\| !kobj->sd \|\| !attr);
1da177e4	488
608e266a	489	return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
1da177e4 LT	490	}
	491
	492
	493	/**
	494	* sysfs_remove_bin_file - remove binary file for object.
	495	* @kobj: object.
	496	* @attr: attribute descriptor.
1da177e4 LT	497	*/
1da177e4 LT	498
66ecb92b PC	499	void sysfs_remove_bin_file(struct kobject *kobj,
66ecb92b PC	500	const struct bin_attribute *attr)
1da177e4	501	{
3ff195b0	502	sysfs_hash_and_remove(kobj->sd, NULL, attr->attr.name);
1da177e4 LT	503	}
	504
	505	EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
	506	EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);