[linux-2.6-block.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 dentry *dentry, char *buffer, loff_t off, size_t count)
{
	struct sysfs_dirent *attr_sd = 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_two(attr_sd))
		return -ENODEV;

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

	sysfs_put_active_two(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;
	struct dentry *dentry = file->f_path.dentry;
	int size = 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(dentry, 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 dentry *dentry, char *buffer, loff_t offset, size_t count)
{
	struct sysfs_dirent *attr_sd = 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_two(attr_sd))
		return -ENODEV;

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

	sysfs_put_active_two(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;
	struct dentry *dentry = file->f_path.dentry;
	int size = 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(dentry, 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 || !bb->vm_ops->open)
		return;

	if (!sysfs_get_active_two(attr_sd))
		return;

	bb->vm_ops->open(vma);

	sysfs_put_active_two(attr_sd);
}

static void bin_vma_close(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 || !bb->vm_ops->close)
		return;

	if (!sysfs_get_active_two(attr_sd))
		return;

	bb->vm_ops->close(vma);

	sysfs_put_active_two(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 || !bb->vm_ops->fault)
		return VM_FAULT_SIGBUS;

	if (!sysfs_get_active_two(attr_sd))
		return VM_FAULT_SIGBUS;

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

	sysfs_put_active_two(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 (!bb->vm_ops->page_mkwrite)
		return 0;

	if (!sysfs_get_active_two(attr_sd))
		return VM_FAULT_SIGBUS;

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

	sysfs_put_active_two(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 || !bb->vm_ops->access)
		return -EINVAL;

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

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

	sysfs_put_active_two(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 || !bb->vm_ops->set_policy)
		return 0;

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

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

	sysfs_put_active_two(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 || !bb->vm_ops->get_policy)
		return vma->vm_policy;

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

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

	sysfs_put_active_two(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 || !bb->vm_ops->migrate)
		return 0;

	if (!sysfs_get_active_two(attr_sd))
		return 0;

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

	sysfs_put_active_two(attr_sd);
	return ret;
}
#endif

static const struct vm_operations_struct bin_vm_ops = {
	.open		= bin_vma_open,
	.close		= bin_vma_close,
	.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_two(attr_sd))
		goto out_unlock;

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

	rc = attr->mmap(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;

	rc = 0;
	bb->mmapped = 1;
	bb->vm_ops = vma->vm_ops;
	vma->vm_ops = &bin_vm_ops;
out_put:
	sysfs_put_active_two(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_two(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_two(attr_sd);
	return 0;

 err_out:
	sysfs_put_active_two(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, 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, struct bin_attribute * attr)
{
	sysfs_hash_and_remove(kobj->sd, 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 LT	48	static int
	49	fill_read(struct dentry dentry, char buffer, loff_t off, size_t count)
	50	{
3e519038	51	struct sysfs_dirent *attr_sd = 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 */
	57	if (!sysfs_get_active_two(attr_sd))
	58	return -ENODEV;
1da177e4	59
0ab66088 TH	60	rc = -EIO;
0ab66088 TH	61	if (attr->read)
91a69029	62	rc = attr->read(kobj, attr, buffer, off, count);
1da177e4	63
0ab66088 TH	64	sysfs_put_active_two(attr_sd);
	65
	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;
f427f5d5	73	struct dentry *dentry = file->f_path.dentry;
1da177e4 LT	74	int size = dentry->d_inode->i_size;
1da177e4 LT	75	loff_t offs = *off;
93e3cd82	76	int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5	77	char *temp;
1da177e4	78
4503efd0 GKH	79	if (!bytes)
	80	return 0;
	81
1da177e4 LT	82	if (size) {
	83	if (offs > size)
	84	return 0;
	85	if (offs + count > size)
	86	count = size - offs;
	87	}
	88
b31ca3f5 NP	89	temp = kmalloc(count, GFP_KERNEL);
	90	if (!temp)
	91	return -ENOMEM;
	92
eb361653 TH	93	mutex_lock(&bb->mutex);
	94
	95	count = fill_read(dentry, bb->buffer, offs, count);
b31ca3f5 NP	96	if (count < 0) {
	97	mutex_unlock(&bb->mutex);
	98	goto out_free;
	99	}
1da177e4	100
b31ca3f5 NP	101	memcpy(temp, bb->buffer, count);
	102
	103	mutex_unlock(&bb->mutex);
	104
	105	if (copy_to_user(userbuf, temp, count)) {
eb361653	106	count = -EFAULT;
b31ca3f5	107	goto out_free;
eb361653	108	}
1da177e4	109
93e3cd82	110	pr_debug("offs = %lld, off = %lld, count = %d\n", offs, off, count);
1da177e4 LT	111
	112	*off = offs + count;
	113
b31ca3f5 NP	114	out_free:
b31ca3f5 NP	115	kfree(temp);
1da177e4 LT	116	return count;
	117	}
	118
	119	static int
	120	flush_write(struct dentry dentry, char buffer, loff_t offset, size_t count)
	121	{
3e519038	122	struct sysfs_dirent *attr_sd = dentry->d_fsdata;
b1fc3d61 TH	123	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	124	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
0ab66088 TH	125	int rc;
	126
	127	/* need attr_sd for attr, its parent for kobj */
	128	if (!sysfs_get_active_two(attr_sd))
	129	return -ENODEV;
1da177e4	130
0ab66088 TH	131	rc = -EIO;
0ab66088 TH	132	if (attr->write)
91a69029	133	rc = attr->write(kobj, attr, buffer, offset, count);
1da177e4	134
0ab66088 TH	135	sysfs_put_active_two(attr_sd);
	136
	137	return rc;
1da177e4 LT	138	}
1da177e4 LT	139
93e3cd82 TH	140	static ssize_t write(struct file file, const char __user userbuf,
93e3cd82 TH	141	size_t bytes, loff_t *off)
1da177e4	142	{
eb361653	143	struct bin_buffer *bb = file->private_data;
f427f5d5	144	struct dentry *dentry = file->f_path.dentry;
1da177e4 LT	145	int size = dentry->d_inode->i_size;
1da177e4 LT	146	loff_t offs = *off;
93e3cd82	147	int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5	148	char *temp;
1da177e4	149
4503efd0 GKH	150	if (!bytes)
	151	return 0;
	152
1da177e4 LT	153	if (size) {
	154	if (offs > size)
	155	return 0;
	156	if (offs + count > size)
	157	count = size - offs;
	158	}
	159
1c8542c7 LZ	160	temp = memdup_user(userbuf, count);
	161	if (IS_ERR(temp))
	162	return PTR_ERR(temp);
1da177e4	163
b31ca3f5 NP	164	mutex_lock(&bb->mutex);
	165
	166	memcpy(bb->buffer, temp, count);
	167
eb361653	168	count = flush_write(dentry, bb->buffer, offs, count);
b31ca3f5 NP	169	mutex_unlock(&bb->mutex);
b31ca3f5 NP	170
1da177e4 LT	171	if (count > 0)
1da177e4 LT	172	*off = offs + count;
eb361653	173
d5ce5b40	174	kfree(temp);
1da177e4 LT	175	return count;
	176	}
	177
e0edd3c6 EB	178	static void bin_vma_open(struct vm_area_struct *vma)
	179	{
	180	struct file *file = vma->vm_file;
	181	struct bin_buffer *bb = file->private_data;
	182	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	183
	184	if (!bb->vm_ops \|\| !bb->vm_ops->open)
	185	return;
	186
	187	if (!sysfs_get_active_two(attr_sd))
	188	return;
	189
	190	bb->vm_ops->open(vma);
	191
	192	sysfs_put_active_two(attr_sd);
	193	}
	194
	195	static void bin_vma_close(struct vm_area_struct *vma)
	196	{
	197	struct file *file = vma->vm_file;
	198	struct bin_buffer *bb = file->private_data;
	199	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	200
	201	if (!bb->vm_ops \|\| !bb->vm_ops->close)
	202	return;
	203
	204	if (!sysfs_get_active_two(attr_sd))
	205	return;
	206
	207	bb->vm_ops->close(vma);
	208
	209	sysfs_put_active_two(attr_sd);
	210	}
	211
	212	static int bin_fault(struct vm_area_struct vma, struct vm_fault vmf)
	213	{
	214	struct file *file = vma->vm_file;
	215	struct bin_buffer *bb = file->private_data;
	216	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	217	int ret;
	218
	219	if (!bb->vm_ops \|\| !bb->vm_ops->fault)
	220	return VM_FAULT_SIGBUS;
	221
	222	if (!sysfs_get_active_two(attr_sd))
	223	return VM_FAULT_SIGBUS;
	224
	225	ret = bb->vm_ops->fault(vma, vmf);
	226
	227	sysfs_put_active_two(attr_sd);
	228	return ret;
	229	}
	230
851a039c	231	static int bin_page_mkwrite(struct vm_area_struct vma, struct vm_fault vmf)
e0edd3c6 EB	232	{
	233	struct file *file = vma->vm_file;
	234	struct bin_buffer *bb = file->private_data;
	235	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	236	int ret;
	237
095160ae	238	if (!bb->vm_ops)
851a039c	239	return VM_FAULT_SIGBUS;
e0edd3c6	240
095160ae HD	241	if (!bb->vm_ops->page_mkwrite)
	242	return 0;
	243
e0edd3c6	244	if (!sysfs_get_active_two(attr_sd))
851a039c	245	return VM_FAULT_SIGBUS;
e0edd3c6	246
851a039c	247	ret = bb->vm_ops->page_mkwrite(vma, vmf);
e0edd3c6 EB	248
	249	sysfs_put_active_two(attr_sd);
	250	return ret;
	251	}
	252
	253	static int bin_access(struct vm_area_struct *vma, unsigned long addr,
	254	void *buf, int len, int write)
	255	{
	256	struct file *file = vma->vm_file;
	257	struct bin_buffer *bb = file->private_data;
	258	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	259	int ret;
	260
	261	if (!bb->vm_ops \|\| !bb->vm_ops->access)
	262	return -EINVAL;
	263
	264	if (!sysfs_get_active_two(attr_sd))
	265	return -EINVAL;
	266
	267	ret = bb->vm_ops->access(vma, addr, buf, len, write);
	268
	269	sysfs_put_active_two(attr_sd);
	270	return ret;
	271	}
	272
095160ae HD	273	#ifdef CONFIG_NUMA
	274	static int bin_set_policy(struct vm_area_struct vma, struct mempolicy new)
	275	{
	276	struct file *file = vma->vm_file;
	277	struct bin_buffer *bb = file->private_data;
	278	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	279	int ret;
	280
	281	if (!bb->vm_ops \|\| !bb->vm_ops->set_policy)
	282	return 0;
	283
	284	if (!sysfs_get_active_two(attr_sd))
	285	return -EINVAL;
	286
	287	ret = bb->vm_ops->set_policy(vma, new);
	288
	289	sysfs_put_active_two(attr_sd);
	290	return ret;
	291	}
	292
	293	static struct mempolicy bin_get_policy(struct vm_area_struct vma,
	294	unsigned long addr)
	295	{
	296	struct file *file = vma->vm_file;
	297	struct bin_buffer *bb = file->private_data;
	298	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	299	struct mempolicy *pol;
	300
	301	if (!bb->vm_ops \|\| !bb->vm_ops->get_policy)
	302	return vma->vm_policy;
	303
	304	if (!sysfs_get_active_two(attr_sd))
	305	return vma->vm_policy;
	306
	307	pol = bb->vm_ops->get_policy(vma, addr);
	308
	309	sysfs_put_active_two(attr_sd);
	310	return pol;
	311	}
	312
	313	static int bin_migrate(struct vm_area_struct vma, const nodemask_t from,
	314	const nodemask_t *to, unsigned long flags)
	315	{
	316	struct file *file = vma->vm_file;
	317	struct bin_buffer *bb = file->private_data;
	318	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
	319	int ret;
	320
	321	if (!bb->vm_ops \|\| !bb->vm_ops->migrate)
	322	return 0;
	323
	324	if (!sysfs_get_active_two(attr_sd))
	325	return 0;
	326
	327	ret = bb->vm_ops->migrate(vma, from, to, flags);
	328
	329	sysfs_put_active_two(attr_sd);
	330	return ret;
	331	}
	332	#endif
	333
f0f37e2f	334	static const struct vm_operations_struct bin_vm_ops = {
e0edd3c6 EB	335	.open = bin_vma_open,
	336	.close = bin_vma_close,
	337	.fault = bin_fault,
	338	.page_mkwrite = bin_page_mkwrite,
	339	.access = bin_access,
095160ae HD	340	#ifdef CONFIG_NUMA
	341	.set_policy = bin_set_policy,
	342	.get_policy = bin_get_policy,
	343	.migrate = bin_migrate,
	344	#endif
e0edd3c6 EB	345	};
e0edd3c6 EB	346
1da177e4 LT	347	static int mmap(struct file file, struct vm_area_struct vma)
1da177e4 LT	348	{
eb361653	349	struct bin_buffer *bb = file->private_data;
3e519038	350	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 TH	351	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
b1fc3d61 TH	352	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
eb361653	353	int rc;
1da177e4	354
eb361653	355	mutex_lock(&bb->mutex);
0ab66088 TH	356
0ab66088 TH	357	/* need attr_sd for attr, its parent for kobj */
e0edd3c6	358	rc = -ENODEV;
0ab66088	359	if (!sysfs_get_active_two(attr_sd))
e0edd3c6	360	goto out_unlock;
0ab66088 TH	361
0ab66088 TH	362	rc = -EINVAL;
e0edd3c6 EB	363	if (!attr->mmap)
e0edd3c6 EB	364	goto out_put;
0ab66088	365
e0edd3c6	366	rc = attr->mmap(kobj, attr, vma);
e0edd3c6 EB	367	if (rc)
e0edd3c6 EB	368	goto out_put;
0ab66088	369
095160ae HD	370	/*
	371	* PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
	372	* to satisfy versions of X which crash if the mmap fails: that
	373	* substitutes a new vm_file, and we don't then want bin_vm_ops.
	374	*/
	375	if (vma->vm_file != file)
e0edd3c6 EB	376	goto out_put;
e0edd3c6 EB	377
e0edd3c6	378	rc = -EINVAL;
095160ae	379	if (bb->mmapped && bb->vm_ops != vma->vm_ops)
e0edd3c6	380	goto out_put;
e0edd3c6 EB	381
	382	rc = 0;
	383	bb->mmapped = 1;
095160ae HD	384	bb->vm_ops = vma->vm_ops;
095160ae HD	385	vma->vm_ops = &bin_vm_ops;
e0edd3c6 EB	386	out_put:
	387	sysfs_put_active_two(attr_sd);
	388	out_unlock:
eb361653 TH	389	mutex_unlock(&bb->mutex);
	390
	391	return rc;
1da177e4 LT	392	}
	393
	394	static int open(struct inode * inode, struct file * file)
	395	{
3e519038	396	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61	397	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
eb361653	398	struct bin_buffer *bb = NULL;
0ab66088	399	int error;
1da177e4	400
078ce640 TH	401	/* binary file operations requires both @sd and its parent */
078ce640 TH	402	if (!sysfs_get_active_two(attr_sd))
0ab66088	403	return -ENODEV;
1da177e4	404
1da177e4 LT	405	error = -EACCES;
1da177e4 LT	406	if ((file->f_mode & FMODE_WRITE) && !(attr->write \|\| attr->mmap))
7b595756	407	goto err_out;
1da177e4	408	if ((file->f_mode & FMODE_READ) && !(attr->read \|\| attr->mmap))
7b595756	409	goto err_out;
1da177e4 LT	410
1da177e4 LT	411	error = -ENOMEM;
eb361653 TH	412	bb = kzalloc(sizeof(*bb), GFP_KERNEL);
eb361653 TH	413	if (!bb)
7b595756	414	goto err_out;
1da177e4	415
eb361653 TH	416	bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
eb361653 TH	417	if (!bb->buffer)
7b595756	418	goto err_out;
eb361653 TH	419
eb361653 TH	420	mutex_init(&bb->mutex);
e0edd3c6	421	bb->file = file;
eb361653 TH	422	file->private_data = bb;
eb361653 TH	423
e0edd3c6 EB	424	mutex_lock(&sysfs_bin_lock);
	425	hlist_add_head(&bb->list, &attr_sd->s_bin_attr.buffers);
	426	mutex_unlock(&sysfs_bin_lock);
	427
078ce640 TH	428	/* open succeeded, put active references */
078ce640 TH	429	sysfs_put_active_two(attr_sd);
0ab66088	430	return 0;
1da177e4	431
7b595756	432	err_out:
078ce640	433	sysfs_put_active_two(attr_sd);
0ab66088	434	kfree(bb);
1da177e4 LT	435	return error;
	436	}
	437
	438	static int release(struct inode * inode, struct file * file)
	439	{
eb361653	440	struct bin_buffer *bb = file->private_data;
1da177e4	441
e0edd3c6 EB	442	mutex_lock(&sysfs_bin_lock);
	443	hlist_del(&bb->list);
	444	mutex_unlock(&sysfs_bin_lock);
	445
eb361653 TH	446	kfree(bb->buffer);
eb361653 TH	447	kfree(bb);
1da177e4 LT	448	return 0;
	449	}
	450
4b6f5d20	451	const struct file_operations bin_fops = {
1da177e4 LT	452	.read = read,
	453	.write = write,
	454	.mmap = mmap,
	455	.llseek = generic_file_llseek,
	456	.open = open,
	457	.release = release,
	458	};
	459
e0edd3c6 EB	460
	461	void unmap_bin_file(struct sysfs_dirent *attr_sd)
	462	{
	463	struct bin_buffer *bb;
	464	struct hlist_node *tmp;
	465
	466	if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR)
	467	return;
	468
	469	mutex_lock(&sysfs_bin_lock);
	470
	471	hlist_for_each_entry(bb, tmp, &attr_sd->s_bin_attr.buffers, list) {
	472	struct inode *inode = bb->file->f_path.dentry->d_inode;
	473
	474	unmap_mapping_range(inode->i_mapping, 0, 0, 1);
	475	}
	476
	477	mutex_unlock(&sysfs_bin_lock);
	478	}
	479
1da177e4 LT	480	/**
	481	* sysfs_create_bin_file - create binary file for object.
	482	* @kobj: object.
	483	* @attr: attribute descriptor.
1da177e4 LT	484	*/
	485
	486	int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
	487	{
608e266a	488	BUG_ON(!kobj \|\| !kobj->sd \|\| !attr);
1da177e4	489
608e266a	490	return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
1da177e4 LT	491	}
	492
	493
	494	/**
	495	* sysfs_remove_bin_file - remove binary file for object.
	496	* @kobj: object.
	497	* @attr: attribute descriptor.
1da177e4 LT	498	*/
1da177e4 LT	499
995982ca	500	void sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
1da177e4	501	{
5f1835da	502	sysfs_hash_and_remove(kobj->sd, attr->attr.name);
1da177e4 LT	503	}
	504
	505	EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
	506	EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);