bitmap.h

linux 内核源代码

/*
 * bitmap.h - Defines for NTFS kernel bitmap handling.  Part of the Linux-NTFS
 *	      project.
 *
 * Copyright (c) 2004 Anton Altaparmakov
 *
 * This program/include file is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program/include file is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program (in the main directory of the Linux-NTFS
 * distribution in the file COPYING); if not, write to the Free Software
 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifndef _LINUX_NTFS_BITMAP_H
#define _LINUX_NTFS_BITMAP_H

#ifdef NTFS_RW

#include <linux/fs.h>

#include "types.h"

extern int __ntfs_bitmap_set_bits_in_run(struct inode *vi, const s64 start_bit,
		const s64 count, const u8 value, const bool is_rollback);

/**
 * ntfs_bitmap_set_bits_in_run - set a run of bits in a bitmap to a value
 * @vi:			vfs inode describing the bitmap
 * @start_bit:		first bit to set
 * @count:		number of bits to set
 * @value:		value to set the bits to (i.e. 0 or 1)
 *
 * Set @count bits starting at bit @start_bit in the bitmap described by the
 * vfs inode @vi to @value, where @value is either 0 or 1.
 *
 * Return 0 on success and -errno on error.
 */
static inline int ntfs_bitmap_set_bits_in_run(struct inode *vi,
		const s64 start_bit, const s64 count, const u8 value)
{
	return __ntfs_bitmap_set_bits_in_run(vi, start_bit, count, value,
			false);
}

/**
 * ntfs_bitmap_set_run - set a run of bits in a bitmap
 * @vi:		vfs inode describing the bitmap
 * @start_bit:	first bit to set
 * @count:	number of bits to set
 *
 * Set @count bits starting at bit @start_bit in the bitmap described by the
 * vfs inode @vi.
 *
 * Return 0 on success and -errno on error.
 */
static inline int ntfs_bitmap_set_run(struct inode *vi, const s64 start_bit,
		const s64 count)
{
	return ntfs_bitmap_set_bits_in_run(vi, start_bit, count, 1);
}

/**
 * ntfs_bitmap_clear_run - clear a run of bits in a bitmap
 * @vi:		vfs inode describing the bitmap
 * @start_bit:	first bit to clear
 * @count:	number of bits to clear
 *
 * Clear @count bits starting at bit @start_bit in the bitmap described by the
 * vfs inode @vi.
 *
 * Return 0 on success and -errno on error.
 */
static inline int ntfs_bitmap_clear_run(struct inode *vi, const s64 start_bit,
		const s64 count)
{
	return ntfs_bitmap_set_bits_in_run(vi, start_bit, count, 0);
}

/**
 * ntfs_bitmap_set_bit - set a bit in a bitmap
 * @vi:		vfs inode describing the bitmap
 * @bit:	bit to set
 *
 * Set bit @bit in the bitmap described by the vfs inode @vi.
 *
 * Return 0 on success and -errno on error.
 */
static inline int ntfs_bitmap_set_bit(struct inode *vi, const s64 bit)
{
	return ntfs_bitmap_set_run(vi, bit, 1);
}

/**
 * ntfs_bitmap_clear_bit - clear a bit in a bitmap
 * @vi:		vfs inode describing the bitmap
 * @bit:	bit to clear
 *
 * Clear bit @bit in the bitmap described by the vfs inode @vi.
 *
 * Return 0 on success and -errno on error.
 */
static inline int ntfs_bitmap_clear_bit(struct inode *vi, const s64 bit)
{
	return ntfs_bitmap_clear_run(vi, bit, 1);
}

#endif /* NTFS_RW */

#endif /* defined _LINUX_NTFS_BITMAP_H */