1 /* segment.h: MMU segment settings 2 * 3 * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #ifndef _ASM_SEGMENT_H 13 #define _ASM_SEGMENT_H 14 15 16 #ifndef __ASSEMBLY__ 17 18 typedef struct { 19 unsigned long seg; 20 } mm_segment_t; 21 22 #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) 23 24 #ifdef CONFIG_MMU 25 #define USER_DS MAKE_MM_SEG(TASK_SIZE - 1) 26 #define KERNEL_DS MAKE_MM_SEG(0xdfffffffUL) 27 #else 28 #define USER_DS MAKE_MM_SEG(memory_end) 29 #define KERNEL_DS MAKE_MM_SEG(0xe0000000UL) 30 #endif 31 32 #define get_ds() (KERNEL_DS) 33 #define get_fs() (__current_thread_info->addr_limit) 34 #define segment_eq(a, b) ((a).seg == (b).seg) 35 #define get_addr_limit() (get_fs().seg) 36 37 #define set_fs(_x) \ 38 do { \ 39 __current_thread_info->addr_limit = (_x); \ 40 } while(0) 41 42 43 #endif /* __ASSEMBLY__ */ 44 #endif /* _ASM_SEGMENT_H */ 45