[deliverable/linux.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 <linux/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_inode(file)->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_inode(file)->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);
	else
		file_update_time(file);

	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;

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

	mutex_lock(&sysfs_bin_lock);

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

		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);
}
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)
{
	sysfs_hash_and_remove(kobj->sd, NULL, attr->attr.name);
}
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>
060cc749	25	#include <linux/uaccess.h>
1da177e4 LT	26
	27	#include "sysfs.h"
	28
e0edd3c6 EB	29	/*
	30	* There's one bin_buffer for each open file.
	31	*
	32	* filp->private_data points to bin_buffer and
	33	* sysfs_dirent->s_bin_attr.buffers points to a the bin_buffer s
	34	* sysfs_dirent->s_bin_attr.buffers is protected by sysfs_bin_lock
	35	*/
	36	static DEFINE_MUTEX(sysfs_bin_lock);
	37
eb361653	38	struct bin_buffer {
e0edd3c6 EB	39	struct mutex mutex;
	40	void *buffer;
	41	int mmapped;
f0f37e2f	42	const struct vm_operations_struct *vm_ops;
e0edd3c6 EB	43	struct file *file;
e0edd3c6 EB	44	struct hlist_node list;
eb361653 TH	45	};
eb361653 TH	46
1da177e4	47	static int
2c3c8bea	48	fill_read(struct file file, char buffer, loff_t off, size_t count)
1da177e4	49	{
2c3c8bea	50	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 TH	51	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	52	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
0ab66088 TH	53	int rc;
	54
	55	/* need attr_sd for attr, its parent for kobj */
e72ceb8c	56	if (!sysfs_get_active(attr_sd))
0ab66088	57	return -ENODEV;
1da177e4	58
0ab66088 TH	59	rc = -EIO;
0ab66088 TH	60	if (attr->read)
2c3c8bea	61	rc = attr->read(file, kobj, attr, buffer, off, count);
1da177e4	62
e72ceb8c	63	sysfs_put_active(attr_sd);
0ab66088 TH	64
0ab66088 TH	65	return rc;
1da177e4 LT	66	}
	67
	68	static ssize_t
93e3cd82	69	read(struct file file, char __user userbuf, size_t bytes, loff_t *off)
1da177e4	70	{
eb361653	71	struct bin_buffer *bb = file->private_data;
496ad9aa	72	int size = file_inode(file)->i_size;
1da177e4	73	loff_t offs = *off;
93e3cd82	74	int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5	75	char *temp;
1da177e4	76
4503efd0 GKH	77	if (!bytes)
	78	return 0;
	79
1da177e4 LT	80	if (size) {
	81	if (offs > size)
	82	return 0;
	83	if (offs + count > size)
	84	count = size - offs;
	85	}
	86
b31ca3f5 NP	87	temp = kmalloc(count, GFP_KERNEL);
	88	if (!temp)
	89	return -ENOMEM;
	90
eb361653 TH	91	mutex_lock(&bb->mutex);
eb361653 TH	92
2c3c8bea	93	count = fill_read(file, bb->buffer, offs, count);
b31ca3f5 NP	94	if (count < 0) {
	95	mutex_unlock(&bb->mutex);
	96	goto out_free;
	97	}
1da177e4	98
b31ca3f5 NP	99	memcpy(temp, bb->buffer, count);
	100
	101	mutex_unlock(&bb->mutex);
	102
	103	if (copy_to_user(userbuf, temp, count)) {
eb361653	104	count = -EFAULT;
b31ca3f5	105	goto out_free;
eb361653	106	}
1da177e4	107
93e3cd82	108	pr_debug("offs = %lld, off = %lld, count = %d\n", offs, off, count);
1da177e4 LT	109
	110	*off = offs + count;
	111
b31ca3f5 NP	112	out_free:
b31ca3f5 NP	113	kfree(temp);
1da177e4 LT	114	return count;
	115	}
	116
	117	static int
2c3c8bea	118	flush_write(struct file file, char buffer, loff_t offset, size_t count)
1da177e4	119	{
2c3c8bea	120	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 TH	121	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	122	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
0ab66088 TH	123	int rc;
	124
	125	/* need attr_sd for attr, its parent for kobj */
e72ceb8c	126	if (!sysfs_get_active(attr_sd))
0ab66088	127	return -ENODEV;
1da177e4	128
0ab66088 TH	129	rc = -EIO;
0ab66088 TH	130	if (attr->write)
2c3c8bea	131	rc = attr->write(file, kobj, attr, buffer, offset, count);
1da177e4	132
e72ceb8c	133	sysfs_put_active(attr_sd);
0ab66088 TH	134
0ab66088 TH	135	return rc;
1da177e4 LT	136	}
1da177e4 LT	137
93e3cd82 TH	138	static ssize_t write(struct file file, const char __user userbuf,
93e3cd82 TH	139	size_t bytes, loff_t *off)
1da177e4	140	{
eb361653	141	struct bin_buffer *bb = file->private_data;
496ad9aa	142	int size = file_inode(file)->i_size;
1da177e4	143	loff_t offs = *off;
93e3cd82	144	int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5	145	char *temp;
1da177e4	146
4503efd0 GKH	147	if (!bytes)
	148	return 0;
	149
1da177e4 LT	150	if (size) {
	151	if (offs > size)
	152	return 0;
	153	if (offs + count > size)
	154	count = size - offs;
	155	}
	156
1c8542c7 LZ	157	temp = memdup_user(userbuf, count);
	158	if (IS_ERR(temp))
	159	return PTR_ERR(temp);
1da177e4	160
b31ca3f5 NP	161	mutex_lock(&bb->mutex);
	162
	163	memcpy(bb->buffer, temp, count);
	164
2c3c8bea	165	count = flush_write(file, bb->buffer, offs, count);
b31ca3f5 NP	166	mutex_unlock(&bb->mutex);
b31ca3f5 NP	167
1da177e4 LT	168	if (count > 0)
1da177e4 LT	169	*off = offs + count;
eb361653	170
d5ce5b40	171	kfree(temp);
1da177e4 LT	172	return count;
	173	}
	174
e0edd3c6 EB	175	static void bin_vma_open(struct vm_area_struct *vma)
	176	{
	177	struct file *file = vma->vm_file;
	178	struct bin_buffer *bb = file->private_data;
	179	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	180
38f49a51	181	if (!bb->vm_ops)
e0edd3c6 EB	182	return;
e0edd3c6 EB	183
e72ceb8c	184	if (!sysfs_get_active(attr_sd))
e0edd3c6 EB	185	return;
e0edd3c6 EB	186
38f49a51 EB	187	if (bb->vm_ops->open)
38f49a51 EB	188	bb->vm_ops->open(vma);
e0edd3c6	189
e72ceb8c	190	sysfs_put_active(attr_sd);
e0edd3c6 EB	191	}
e0edd3c6 EB	192
e0edd3c6 EB	193	static int bin_fault(struct vm_area_struct vma, struct vm_fault vmf)
	194	{
	195	struct file *file = vma->vm_file;
	196	struct bin_buffer *bb = file->private_data;
	197	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	198	int ret;
	199
38f49a51	200	if (!bb->vm_ops)
e0edd3c6 EB	201	return VM_FAULT_SIGBUS;
e0edd3c6 EB	202
e72ceb8c	203	if (!sysfs_get_active(attr_sd))
e0edd3c6 EB	204	return VM_FAULT_SIGBUS;
e0edd3c6 EB	205
38f49a51 EB	206	ret = VM_FAULT_SIGBUS;
	207	if (bb->vm_ops->fault)
	208	ret = bb->vm_ops->fault(vma, vmf);
e0edd3c6	209
e72ceb8c	210	sysfs_put_active(attr_sd);
e0edd3c6 EB	211	return ret;
	212	}
	213
851a039c	214	static int bin_page_mkwrite(struct vm_area_struct vma, struct vm_fault vmf)
e0edd3c6 EB	215	{
	216	struct file *file = vma->vm_file;
	217	struct bin_buffer *bb = file->private_data;
	218	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	219	int ret;
	220
095160ae	221	if (!bb->vm_ops)
851a039c	222	return VM_FAULT_SIGBUS;
e0edd3c6	223
e72ceb8c	224	if (!sysfs_get_active(attr_sd))
851a039c	225	return VM_FAULT_SIGBUS;
e0edd3c6	226
38f49a51 EB	227	ret = 0;
	228	if (bb->vm_ops->page_mkwrite)
	229	ret = bb->vm_ops->page_mkwrite(vma, vmf);
14ae417c JK	230	else
14ae417c JK	231	file_update_time(file);
e0edd3c6	232
e72ceb8c	233	sysfs_put_active(attr_sd);
e0edd3c6 EB	234	return ret;
	235	}
	236
	237	static int bin_access(struct vm_area_struct *vma, unsigned long addr,
	238	void *buf, int len, int write)
	239	{
	240	struct file *file = vma->vm_file;
	241	struct bin_buffer *bb = file->private_data;
	242	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	243	int ret;
	244
38f49a51	245	if (!bb->vm_ops)
e0edd3c6 EB	246	return -EINVAL;
e0edd3c6 EB	247
e72ceb8c	248	if (!sysfs_get_active(attr_sd))
e0edd3c6 EB	249	return -EINVAL;
e0edd3c6 EB	250
38f49a51 EB	251	ret = -EINVAL;
	252	if (bb->vm_ops->access)
	253	ret = bb->vm_ops->access(vma, addr, buf, len, write);
e0edd3c6	254
e72ceb8c	255	sysfs_put_active(attr_sd);
e0edd3c6 EB	256	return ret;
	257	}
	258
095160ae HD	259	#ifdef CONFIG_NUMA
	260	static int bin_set_policy(struct vm_area_struct vma, struct mempolicy new)
	261	{
	262	struct file *file = vma->vm_file;
	263	struct bin_buffer *bb = file->private_data;
	264	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	265	int ret;
	266
38f49a51	267	if (!bb->vm_ops)
095160ae HD	268	return 0;
095160ae HD	269
e72ceb8c	270	if (!sysfs_get_active(attr_sd))
095160ae HD	271	return -EINVAL;
095160ae HD	272
38f49a51 EB	273	ret = 0;
	274	if (bb->vm_ops->set_policy)
	275	ret = bb->vm_ops->set_policy(vma, new);
095160ae	276
e72ceb8c	277	sysfs_put_active(attr_sd);
095160ae HD	278	return ret;
	279	}
	280
	281	static struct mempolicy bin_get_policy(struct vm_area_struct vma,
	282	unsigned long addr)
	283	{
	284	struct file *file = vma->vm_file;
	285	struct bin_buffer *bb = file->private_data;
	286	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	287	struct mempolicy *pol;
	288
38f49a51	289	if (!bb->vm_ops)
095160ae HD	290	return vma->vm_policy;
095160ae HD	291
e72ceb8c	292	if (!sysfs_get_active(attr_sd))
095160ae HD	293	return vma->vm_policy;
095160ae HD	294
38f49a51 EB	295	pol = vma->vm_policy;
	296	if (bb->vm_ops->get_policy)
	297	pol = bb->vm_ops->get_policy(vma, addr);
095160ae	298
e72ceb8c	299	sysfs_put_active(attr_sd);
095160ae HD	300	return pol;
	301	}
	302
	303	static int bin_migrate(struct vm_area_struct vma, const nodemask_t from,
	304	const nodemask_t *to, unsigned long flags)
	305	{
	306	struct file *file = vma->vm_file;
	307	struct bin_buffer *bb = file->private_data;
	308	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	309	int ret;
	310
38f49a51	311	if (!bb->vm_ops)
095160ae HD	312	return 0;
095160ae HD	313
e72ceb8c	314	if (!sysfs_get_active(attr_sd))
095160ae HD	315	return 0;
095160ae HD	316
38f49a51 EB	317	ret = 0;
	318	if (bb->vm_ops->migrate)
	319	ret = bb->vm_ops->migrate(vma, from, to, flags);
095160ae	320
e72ceb8c	321	sysfs_put_active(attr_sd);
095160ae HD	322	return ret;
	323	}
	324	#endif
	325
f0f37e2f	326	static const struct vm_operations_struct bin_vm_ops = {
e0edd3c6	327	.open = bin_vma_open,
e0edd3c6 EB	328	.fault = bin_fault,
	329	.page_mkwrite = bin_page_mkwrite,
	330	.access = bin_access,
095160ae HD	331	#ifdef CONFIG_NUMA
	332	.set_policy = bin_set_policy,
	333	.get_policy = bin_get_policy,
	334	.migrate = bin_migrate,
	335	#endif
e0edd3c6 EB	336	};
e0edd3c6 EB	337
1da177e4 LT	338	static int mmap(struct file file, struct vm_area_struct vma)
1da177e4 LT	339	{
eb361653	340	struct bin_buffer *bb = file->private_data;
3e519038	341	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 TH	342	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	343	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
eb361653	344	int rc;
1da177e4	345
eb361653	346	mutex_lock(&bb->mutex);
0ab66088 TH	347
0ab66088 TH	348	/* need attr_sd for attr, its parent for kobj */
e0edd3c6	349	rc = -ENODEV;
e72ceb8c	350	if (!sysfs_get_active(attr_sd))
e0edd3c6	351	goto out_unlock;
0ab66088 TH	352
0ab66088 TH	353	rc = -EINVAL;
e0edd3c6 EB	354	if (!attr->mmap)
e0edd3c6 EB	355	goto out_put;
0ab66088	356
2c3c8bea	357	rc = attr->mmap(file, kobj, attr, vma);
e0edd3c6 EB	358	if (rc)
e0edd3c6 EB	359	goto out_put;
0ab66088	360
095160ae HD	361	/*
	362	* PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
	363	* to satisfy versions of X which crash if the mmap fails: that
	364	* substitutes a new vm_file, and we don't then want bin_vm_ops.
	365	*/
	366	if (vma->vm_file != file)
e0edd3c6 EB	367	goto out_put;
e0edd3c6 EB	368
e0edd3c6	369	rc = -EINVAL;
095160ae	370	if (bb->mmapped && bb->vm_ops != vma->vm_ops)
e0edd3c6	371	goto out_put;
e0edd3c6	372
a6849fa1 EB	373	/*
	374	* It is not possible to successfully wrap close.
	375	* So error if someone is trying to use close.
	376	*/
	377	rc = -EINVAL;
	378	if (vma->vm_ops && vma->vm_ops->close)
	379	goto out_put;
	380
e0edd3c6 EB	381	rc = 0;
e0edd3c6 EB	382	bb->mmapped = 1;
095160ae HD	383	bb->vm_ops = vma->vm_ops;
095160ae HD	384	vma->vm_ops = &bin_vm_ops;
e0edd3c6	385	out_put:
e72ceb8c	386	sysfs_put_active(attr_sd);
e0edd3c6	387	out_unlock:
eb361653 TH	388	mutex_unlock(&bb->mutex);
	389
	390	return rc;
1da177e4 LT	391	}
1da177e4 LT	392
1b18dc2b	393	static int open(struct inode inode, struct file file)
1da177e4	394	{
3e519038	395	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61	396	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
eb361653	397	struct bin_buffer *bb = NULL;
0ab66088	398	int error;
1da177e4	399
078ce640	400	/* binary file operations requires both @sd and its parent */
e72ceb8c	401	if (!sysfs_get_active(attr_sd))
0ab66088	402	return -ENODEV;
1da177e4	403
1da177e4 LT	404	error = -EACCES;
1da177e4 LT	405	if ((file->f_mode & FMODE_WRITE) && !(attr->write \|\| attr->mmap))
7b595756	406	goto err_out;
1da177e4	407	if ((file->f_mode & FMODE_READ) && !(attr->read \|\| attr->mmap))
7b595756	408	goto err_out;
1da177e4 LT	409
1da177e4 LT	410	error = -ENOMEM;
eb361653 TH	411	bb = kzalloc(sizeof(*bb), GFP_KERNEL);
eb361653 TH	412	if (!bb)
7b595756	413	goto err_out;
1da177e4	414
eb361653 TH	415	bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
eb361653 TH	416	if (!bb->buffer)
7b595756	417	goto err_out;
eb361653 TH	418
eb361653 TH	419	mutex_init(&bb->mutex);
e0edd3c6	420	bb->file = file;
eb361653 TH	421	file->private_data = bb;
eb361653 TH	422
e0edd3c6 EB	423	mutex_lock(&sysfs_bin_lock);
	424	hlist_add_head(&bb->list, &attr_sd->s_bin_attr.buffers);
	425	mutex_unlock(&sysfs_bin_lock);
	426
078ce640	427	/* open succeeded, put active references */
e72ceb8c	428	sysfs_put_active(attr_sd);
0ab66088	429	return 0;
1da177e4	430
7b595756	431	err_out:
e72ceb8c	432	sysfs_put_active(attr_sd);
0ab66088	433	kfree(bb);
1da177e4 LT	434	return error;
	435	}
	436
1b18dc2b	437	static int release(struct inode inode, struct file file)
1da177e4	438	{
eb361653	439	struct bin_buffer *bb = file->private_data;
1da177e4	440
e0edd3c6 EB	441	mutex_lock(&sysfs_bin_lock);
	442	hlist_del(&bb->list);
	443	mutex_unlock(&sysfs_bin_lock);
	444
eb361653 TH	445	kfree(bb->buffer);
eb361653 TH	446	kfree(bb);
1da177e4 LT	447	return 0;
	448	}
	449
4b6f5d20	450	const struct file_operations bin_fops = {
1da177e4 LT	451	.read = read,
	452	.write = write,
	453	.mmap = mmap,
	454	.llseek = generic_file_llseek,
	455	.open = open,
	456	.release = release,
	457	};
	458
e0edd3c6 EB	459
	460	void unmap_bin_file(struct sysfs_dirent *attr_sd)
	461	{
	462	struct bin_buffer *bb;
e0edd3c6 EB	463
	464	if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR)
	465	return;
	466
	467	mutex_lock(&sysfs_bin_lock);
	468
b67bfe0d	469	hlist_for_each_entry(bb, &attr_sd->s_bin_attr.buffers, list) {
496ad9aa	470	struct inode *inode = file_inode(bb->file);
e0edd3c6 EB	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	482	*/
66ecb92b PC	483	int sysfs_create_bin_file(struct kobject *kobj,
66ecb92b PC	484	const struct bin_attribute *attr)
1da177e4	485	{
608e266a	486	BUG_ON(!kobj \|\| !kobj->sd \|\| !attr);
1da177e4	487
608e266a	488	return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
1da177e4	489	}
1b866757	490	EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
1da177e4 LT	491
	492	/**
	493	* sysfs_remove_bin_file - remove binary file for object.
	494	* @kobj: object.
	495	* @attr: attribute descriptor.
1da177e4	496	*/
66ecb92b PC	497	void sysfs_remove_bin_file(struct kobject *kobj,
66ecb92b PC	498	const struct bin_attribute *attr)
1da177e4	499	{
3ff195b0	500	sysfs_hash_and_remove(kobj->sd, NULL, attr->attr.name);
1da177e4	501	}
1da177e4	502	EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);