Linux kernel mirror (for testing)
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1/*
2 * linux/include/asm-arm/memory.h
3 *
4 * Copyright (C) 2000-2002 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Note: this file should not be included by non-asm/.h files
11 */
12#ifndef __ASM_ARM_MEMORY_H
13#define __ASM_ARM_MEMORY_H
14
15#include <linux/config.h>
16#include <linux/compiler.h>
17#include <asm/arch/memory.h>
18
19#ifndef TASK_SIZE
20/*
21 * TASK_SIZE - the maximum size of a user space task.
22 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
23 */
24#define TASK_SIZE (0xbf000000UL)
25#define TASK_UNMAPPED_BASE (0x40000000UL)
26#endif
27
28/*
29 * The maximum size of a 26-bit user space task.
30 */
31#define TASK_SIZE_26 (0x04000000UL)
32
33/*
34 * Page offset: 3GB
35 */
36#ifndef PAGE_OFFSET
37#define PAGE_OFFSET (0xc0000000UL)
38#endif
39
40/*
41 * Physical vs virtual RAM address space conversion. These are
42 * private definitions which should NOT be used outside memory.h
43 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
44 */
45#ifndef __virt_to_phys
46#define __virt_to_phys(x) ((x) - PAGE_OFFSET + PHYS_OFFSET)
47#define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)
48#endif
49
50/*
51 * The module space lives between the addresses given by TASK_SIZE
52 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
53 */
54#define MODULE_END (PAGE_OFFSET)
55#define MODULE_START (MODULE_END - 16*1048576)
56
57#if TASK_SIZE > MODULE_START
58#error Top of user space clashes with start of module space
59#endif
60
61#ifndef __ASSEMBLY__
62
63/*
64 * The DMA mask corresponding to the maximum bus address allocatable
65 * using GFP_DMA. The default here places no restriction on DMA
66 * allocations. This must be the smallest DMA mask in the system,
67 * so a successful GFP_DMA allocation will always satisfy this.
68 */
69#ifndef ISA_DMA_THRESHOLD
70#define ISA_DMA_THRESHOLD (0xffffffffULL)
71#endif
72
73#ifndef arch_adjust_zones
74#define arch_adjust_zones(node,size,holes) do { } while (0)
75#endif
76
77/*
78 * PFNs are used to describe any physical page; this means
79 * PFN 0 == physical address 0.
80 *
81 * This is the PFN of the first RAM page in the kernel
82 * direct-mapped view. We assume this is the first page
83 * of RAM in the mem_map as well.
84 */
85#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
86
87/*
88 * These are *only* valid on the kernel direct mapped RAM memory.
89 * Note: Drivers should NOT use these. They are the wrong
90 * translation for translating DMA addresses. Use the driver
91 * DMA support - see dma-mapping.h.
92 */
93static inline unsigned long virt_to_phys(void *x)
94{
95 return __virt_to_phys((unsigned long)(x));
96}
97
98static inline void *phys_to_virt(unsigned long x)
99{
100 return (void *)(__phys_to_virt((unsigned long)(x)));
101}
102
103/*
104 * Drivers should NOT use these either.
105 */
106#define __pa(x) __virt_to_phys((unsigned long)(x))
107#define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
108
109/*
110 * Virtual <-> DMA view memory address translations
111 * Again, these are *only* valid on the kernel direct mapped RAM
112 * memory. Use of these is *deprecated* (and that doesn't mean
113 * use the __ prefixed forms instead.) See dma-mapping.h.
114 */
115static inline __deprecated unsigned long virt_to_bus(void *x)
116{
117 return __virt_to_bus((unsigned long)x);
118}
119
120static inline __deprecated void *bus_to_virt(unsigned long x)
121{
122 return (void *)__bus_to_virt(x);
123}
124
125/*
126 * Conversion between a struct page and a physical address.
127 *
128 * Note: when converting an unknown physical address to a
129 * struct page, the resulting pointer must be validated
130 * using VALID_PAGE(). It must return an invalid struct page
131 * for any physical address not corresponding to a system
132 * RAM address.
133 *
134 * page_to_pfn(page) convert a struct page * to a PFN number
135 * pfn_to_page(pfn) convert a _valid_ PFN number to struct page *
136 * pfn_valid(pfn) indicates whether a PFN number is valid
137 *
138 * virt_to_page(k) convert a _valid_ virtual address to struct page *
139 * virt_addr_valid(k) indicates whether a virtual address is valid
140 */
141#ifndef CONFIG_DISCONTIGMEM
142
143#define page_to_pfn(page) (((page) - mem_map) + PHYS_PFN_OFFSET)
144#define pfn_to_page(pfn) ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
145#define pfn_valid(pfn) ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
146
147#define virt_to_page(kaddr) (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
148#define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
149
150#define PHYS_TO_NID(addr) (0)
151
152#else /* CONFIG_DISCONTIGMEM */
153
154/*
155 * This is more complex. We have a set of mem_map arrays spread
156 * around in memory.
157 */
158#include <linux/numa.h>
159
160#define page_to_pfn(page) \
161 (( (page) - page_zone(page)->zone_mem_map) \
162 + page_zone(page)->zone_start_pfn)
163#define pfn_to_page(pfn) \
164 (PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
165#define pfn_valid(pfn) (PFN_TO_NID(pfn) < MAX_NUMNODES)
166
167#define virt_to_page(kaddr) \
168 (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
169#define virt_addr_valid(kaddr) (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
170
171/*
172 * Common discontigmem stuff.
173 * PHYS_TO_NID is used by the ARM kernel/setup.c
174 */
175#define PHYS_TO_NID(addr) PFN_TO_NID((addr) >> PAGE_SHIFT)
176
177#endif /* !CONFIG_DISCONTIGMEM */
178
179/*
180 * For BIO. "will die". Kill me when bio_to_phys() and bvec_to_phys() die.
181 */
182#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
183
184/*
185 * Optional device DMA address remapping. Do _not_ use directly!
186 * We should really eliminate virt_to_bus() here - it's deprecated.
187 */
188#ifndef __arch_page_to_dma
189#define page_to_dma(dev, page) ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
190#define dma_to_virt(dev, addr) ((void *)__bus_to_virt(addr))
191#define virt_to_dma(dev, addr) ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
192#else
193#define page_to_dma(dev, page) (__arch_page_to_dma(dev, page))
194#define dma_to_virt(dev, addr) (__arch_dma_to_virt(dev, addr))
195#define virt_to_dma(dev, addr) (__arch_virt_to_dma(dev, addr))
196#endif
197
198#endif
199
200#endif