Linux Kernel  3.7.1
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mem-layout.h
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1 /* mem-layout.h: memory layout
2  *
3  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells ([email protected])
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_MEM_LAYOUT_H
13 #define _ASM_MEM_LAYOUT_H
14 
15 #ifndef __ASSEMBLY__
16 #define __UL(X) ((unsigned long) (X))
17 #else
18 #define __UL(X) (X)
19 #endif
20 
21 /*
22  * PAGE_SHIFT determines the page size
23  */
24 #define PAGE_SHIFT 14
25 
26 #ifndef __ASSEMBLY__
27 #define PAGE_SIZE (1UL << PAGE_SHIFT)
28 #else
29 #define PAGE_SIZE (1 << PAGE_SHIFT)
30 #endif
31 
32 #define PAGE_MASK (~(PAGE_SIZE-1))
33 
34 /*
35  * the slab must be aligned such that load- and store-double instructions don't
36  * fault if used
37  */
38 #define ARCH_DMA_MINALIGN L1_CACHE_BYTES
39 #define ARCH_SLAB_MINALIGN L1_CACHE_BYTES
40 
41 /*****************************************************************************/
42 /*
43  * virtual memory layout from kernel's point of view
44  */
45 #define PAGE_OFFSET ((unsigned long) &__page_offset)
46 
47 #ifdef CONFIG_MMU
48 
49 /* see Documentation/frv/mmu-layout.txt */
50 #define KERNEL_LOWMEM_START __UL(0xc0000000)
51 #define KERNEL_LOWMEM_END __UL(0xd0000000)
52 #define VMALLOC_START __UL(0xd0000000)
53 #define VMALLOC_END __UL(0xd8000000)
54 #define PKMAP_BASE __UL(0xd8000000)
55 #define PKMAP_END __UL(0xdc000000)
56 #define KMAP_ATOMIC_SECONDARY_FRAME __UL(0xdc000000)
57 #define KMAP_ATOMIC_PRIMARY_FRAME __UL(0xdd000000)
58 
59 #endif
60 
61 #define KERNEL_IO_START __UL(0xe0000000)
62 
63 
64 /*****************************************************************************/
65 /*
66  * memory layout from userspace's point of view
67  */
68 #define BRK_BASE __UL(2 * 1024 * 1024 + PAGE_SIZE)
69 #define STACK_TOP __UL(2 * 1024 * 1024)
70 #define STACK_TOP_MAX __UL(0xc0000000)
71 
72 /* userspace process size */
73 #ifdef CONFIG_MMU
74 #define TASK_SIZE (PAGE_OFFSET)
75 #else
76 #define TASK_SIZE __UL(0xFFFFFFFFUL)
77 #endif
78 
79 /* base of area at which unspecified mmaps will start */
80 #ifdef CONFIG_BINFMT_ELF_FDPIC
81 #define TASK_UNMAPPED_BASE __UL(16 * 1024 * 1024)
82 #else
83 #define TASK_UNMAPPED_BASE __UL(TASK_SIZE / 3)
84 #endif
85 
86 #endif /* _ASM_MEM_LAYOUT_H */