arch/microblaze/include/asm/segment.h

/*
 * Copyright (C) 2008 Michal Simek
 * Copyright (C) 2008 PetaLogix
 * Copyright (C) 2006 Atmark Techno, Inc.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#ifndef _ASM_MICROBLAZE_SEGMENT_H
#define _ASM_MICROBLAZE_SEGMENT_H

#ifndef __ASSEMBLY__

typedef struct {
	unsigned long seg;
} mm_segment_t;

/*
 * On Microblaze the fs value is actually the top of the corresponding
 * address space.
 *
 * The fs value determines whether argument validity checking should be
 * performed or not. If get_fs() == USER_DS, checking is performed, with
 * get_fs() == KERNEL_DS, checking is bypassed.
 *
 * For historical reasons, these macros are grossly misnamed.
 *
 * For non-MMU arch like Microblaze, KERNEL_DS and USER_DS is equal.
 */
#  define KERNEL_DS	((mm_segment_t){0})
#  define USER_DS	KERNEL_DS

# define get_ds()	(KERNEL_DS)
# define get_fs()	(current_thread_info()->addr_limit)
# define set_fs(x) \
		do { current_thread_info()->addr_limit = (x); } while (0)

# define segment_eq(a, b)		((a).seg == (b).seg)

# endif /* __ASSEMBLY__ */
#endif /* _ASM_MICROBLAZE_SEGMENT_H */