xref: /haiku/headers/private/kernel/arch/x86/arch_kernel.h (revision 15feb60325be086823e80a3468f7aab2bfbc9f7d)
1 /*
2  * Copyright 2004-2008, Haiku Inc. All rights reserved.
3  * Distributed under the terms of the MIT license.
4  *
5  * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
6  * Distributed under the terms of the NewOS License.
7  */
8 #ifndef _KERNEL_ARCH_x86_KERNEL_H
9 #define _KERNEL_ARCH_x86_KERNEL_H
10 
11 
12 #ifndef _ASSEMBLER
13 #	include <arch/cpu.h>
14 #endif
15 
16 
17 #ifdef _BOOT_MODE
18 
19 
20 // 32-bit and 64-bit kernel load addresses.
21 #define KERNEL_LOAD_BASE		0x80000000
22 #define KERNEL_LOAD_BASE_64BIT	0xffffffff80000000ll
23 
24 
25 #elif defined(__x86_64__)
26 
27 
28 // Base of the kernel address space.
29 // KERNEL_BASE is the base of the kernel address space. This differs from the
30 // address where the kernel is loaded to: the kernel is loaded in the top 2GB
31 // of the virtual address space as required by GCC's kernel code model. The
32 // whole kernel address space is the top 512GB of the address space.
33 #define KERNEL_BASE				0xffffff8000000000
34 #define KERNEL_SIZE				0x8000000000
35 #define KERNEL_TOP  			(KERNEL_BASE + (KERNEL_SIZE - 1))
36 #define KERNEL_LOAD_BASE		0xffffffff80000000
37 
38 // Kernel physical memory map area.
39 #define KERNEL_PMAP_BASE		0xffffff0000000000
40 #define KERNEL_PMAP_SIZE		0x8000000000
41 
42 // Userspace address space layout.
43 #define USER_BASE				0x0
44 #define USER_BASE_ANY			0x100000
45 #define USER_SIZE				0x800000000000
46 #define USER_TOP				(USER_BASE + USER_SIZE)
47 
48 #define KERNEL_USER_DATA_BASE	0x7fffefff0000
49 #define USER_STACK_REGION		0x7ffff0000000
50 #define USER_STACK_REGION_SIZE	(USER_TOP - USER_STACK_REGION)
51 
52 
53 #else	// __x86_64__
54 
55 
56 // memory layout
57 #define KERNEL_BASE				0x80000000
58 #define KERNEL_SIZE				0x80000000
59 #define KERNEL_TOP				(KERNEL_BASE + (KERNEL_SIZE - 1))
60 
61 /* User space layout is a little special:
62  * The user space does not completely cover the space not covered by the
63  * kernel. There is a gap of 64kb between the user and kernel space. The 64kb
64  * region assures a user space thread cannot pass a buffer into the kernel as
65  * part of a syscall that would cross into kernel space.
66  * Furthermore no areas are placed in the lower 1Mb unless the application
67  * explicitly requests it to find null pointer references.
68  * TODO: introduce the 1Mb lower barrier again - it's only used for vm86 mode,
69  *	and this should be moved into the kernel (and address space) completely.
70  */
71 #define USER_BASE				0x00
72 #define USER_BASE_ANY			0x100000
73 #define USER_SIZE				(KERNEL_BASE - 0x10000)
74 #define USER_TOP				(USER_BASE + USER_SIZE)
75 
76 #define KERNEL_USER_DATA_BASE	0x6fff0000
77 #define USER_STACK_REGION		0x70000000
78 #define USER_STACK_REGION_SIZE	(USER_TOP - USER_STACK_REGION)
79 
80 
81 #endif	// __x86_64__
82 
83 #endif	// _KERNEL_ARCH_x86_KERNEL_H
84