swab.h

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/*
 *  linux/fs/ufs/swab.h
 *
 * Copyright (C) 1997, 1998 Francois-Rene Rideau <[e-mail]>
 * Copyright (C) 1998 Jakub Jelinek <[e-mail]>
 * Copyright (C) 2001 Christoph Hellwig <[e-mail]>
 */

#ifndef _UFS_SWAB_H
#define _UFS_SWAB_H

/*
 * Notes:
 *    HERE WE ASSUME EITHER BIG OR LITTLE ENDIAN UFSes
 *    in case there are ufs implementations that have strange bytesexes,
 *    you'll need to modify code here as well as in ufs_super.c and ufs_fs.h
 *    to support them.
 */

enum {
	BYTESEX_LE,
	BYTESEX_BE
};

static __inline u64
fs64_to_cpu(struct super_block *sbp, u64 n)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return le64_to_cpu(n);
	else
		return be64_to_cpu(n);
}

static __inline u64
cpu_to_fs64(struct super_block *sbp, u64 n)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return cpu_to_le64(n);
	else
		return cpu_to_be64(n);
}

static __inline u32
fs64_add(struct super_block *sbp, u32 *n, int d)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return *n = cpu_to_le64(le64_to_cpu(*n)+d);
	else
		return *n = cpu_to_be64(be64_to_cpu(*n)+d);
}

static __inline u32
fs64_sub(struct super_block *sbp, u32 *n, int d)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return *n = cpu_to_le64(le64_to_cpu(*n)-d);
	else
		return *n = cpu_to_be64(be64_to_cpu(*n)-d);
}

static __inline u32
fs32_to_cpu(struct super_block *sbp, u32 n)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return le32_to_cpu(n);
	else
		return be32_to_cpu(n);
}

static __inline u32
cpu_to_fs32(struct super_block *sbp, u32 n)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return cpu_to_le32(n);
	else
		return cpu_to_be32(n);
}

static __inline u32
fs32_add(struct super_block *sbp, u32 *n, int d)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return *n = cpu_to_le32(le32_to_cpu(*n)+d);
	else
		return *n = cpu_to_be32(be32_to_cpu(*n)+d);
}

static __inline u32
fs32_sub(struct super_block *sbp, u32 *n, int d)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return *n = cpu_to_le32(le32_to_cpu(*n)-d);
	else
		return *n = cpu_to_be32(be32_to_cpu(*n)-d);
}

static __inline u16
fs16_to_cpu(struct super_block *sbp, u16 n)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return le16_to_cpu(n);
	else
		return be16_to_cpu(n);
}

static __inline u16
cpu_to_fs16(struct super_block *sbp, u16 n)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return cpu_to_le16(n);
	else
		return cpu_to_be16(n);
}

static __inline u16
fs16_add(struct super_block *sbp, u16 *n, int d)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return *n = cpu_to_le16(le16_to_cpu(*n)+d);
	else
		return *n = cpu_to_be16(be16_to_cpu(*n)+d);
}

static __inline u16
fs16_sub(struct super_block *sbp, u16 *n, int d)
{
	if (sbp->u.ufs_sb.s_bytesex == BYTESEX_LE)
		return *n = cpu_to_le16(le16_to_cpu(*n)-d);
	else
		return *n = cpu_to_be16(be16_to_cpu(*n)-d);
}

#endif /* _UFS_SWAB_H */