Linux kernel mirror (for testing)
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linux
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/*
16 * Allow for constants defined here to be used from assembly code
17 * by prepending the UL suffix only with actual C code compilation.
18 */
19#ifndef __ASSEMBLY__
20#define UL(x) (x##UL)
21#else
22#define UL(x) (x)
23#endif
24
25#include <linux/config.h>
26#include <linux/compiler.h>
27#include <asm/arch/memory.h>
28
29#ifndef TASK_SIZE
30/*
31 * TASK_SIZE - the maximum size of a user space task.
32 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
33 */
34#define TASK_SIZE UL(0xbf000000)
35#define TASK_UNMAPPED_BASE UL(0x40000000)
36#endif
37
38/*
39 * The maximum size of a 26-bit user space task.
40 */
41#define TASK_SIZE_26 UL(0x04000000)
42
43/*
44 * Page offset: 3GB
45 */
46#ifndef PAGE_OFFSET
47#define PAGE_OFFSET UL(0xc0000000)
48#endif
49
50/*
51 * Physical vs virtual RAM address space conversion. These are
52 * private definitions which should NOT be used outside memory.h
53 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
54 */
55#ifndef __virt_to_phys
56#define __virt_to_phys(x) ((x) - PAGE_OFFSET + PHYS_OFFSET)
57#define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)
58#endif
59
60/*
61 * The module space lives between the addresses given by TASK_SIZE
62 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
63 */
64#define MODULE_END (PAGE_OFFSET)
65#define MODULE_START (MODULE_END - 16*1048576)
66
67#if TASK_SIZE > MODULE_START
68#error Top of user space clashes with start of module space
69#endif
70
71/*
72 * The XIP kernel gets mapped at the bottom of the module vm area.
73 * Since we use sections to map it, this macro replaces the physical address
74 * with its virtual address while keeping offset from the base section.
75 */
76#define XIP_VIRT_ADDR(physaddr) (MODULE_START + ((physaddr) & 0x000fffff))
77
78#ifndef __ASSEMBLY__
79
80/*
81 * The DMA mask corresponding to the maximum bus address allocatable
82 * using GFP_DMA. The default here places no restriction on DMA
83 * allocations. This must be the smallest DMA mask in the system,
84 * so a successful GFP_DMA allocation will always satisfy this.
85 */
86#ifndef ISA_DMA_THRESHOLD
87#define ISA_DMA_THRESHOLD (0xffffffffULL)
88#endif
89
90#ifndef arch_adjust_zones
91#define arch_adjust_zones(node,size,holes) do { } while (0)
92#endif
93
94/*
95 * PFNs are used to describe any physical page; this means
96 * PFN 0 == physical address 0.
97 *
98 * This is the PFN of the first RAM page in the kernel
99 * direct-mapped view. We assume this is the first page
100 * of RAM in the mem_map as well.
101 */
102#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
103
104/*
105 * These are *only* valid on the kernel direct mapped RAM memory.
106 * Note: Drivers should NOT use these. They are the wrong
107 * translation for translating DMA addresses. Use the driver
108 * DMA support - see dma-mapping.h.
109 */
110static inline unsigned long virt_to_phys(void *x)
111{
112 return __virt_to_phys((unsigned long)(x));
113}
114
115static inline void *phys_to_virt(unsigned long x)
116{
117 return (void *)(__phys_to_virt((unsigned long)(x)));
118}
119
120/*
121 * Drivers should NOT use these either.
122 */
123#define __pa(x) __virt_to_phys((unsigned long)(x))
124#define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
125
126/*
127 * Virtual <-> DMA view memory address translations
128 * Again, these are *only* valid on the kernel direct mapped RAM
129 * memory. Use of these is *deprecated* (and that doesn't mean
130 * use the __ prefixed forms instead.) See dma-mapping.h.
131 */
132static inline __deprecated unsigned long virt_to_bus(void *x)
133{
134 return __virt_to_bus((unsigned long)x);
135}
136
137static inline __deprecated void *bus_to_virt(unsigned long x)
138{
139 return (void *)__bus_to_virt(x);
140}
141
142/*
143 * Conversion between a struct page and a physical address.
144 *
145 * Note: when converting an unknown physical address to a
146 * struct page, the resulting pointer must be validated
147 * using VALID_PAGE(). It must return an invalid struct page
148 * for any physical address not corresponding to a system
149 * RAM address.
150 *
151 * page_to_pfn(page) convert a struct page * to a PFN number
152 * pfn_to_page(pfn) convert a _valid_ PFN number to struct page *
153 * pfn_valid(pfn) indicates whether a PFN number is valid
154 *
155 * virt_to_page(k) convert a _valid_ virtual address to struct page *
156 * virt_addr_valid(k) indicates whether a virtual address is valid
157 */
158#ifndef CONFIG_DISCONTIGMEM
159
160#define page_to_pfn(page) (((page) - mem_map) + PHYS_PFN_OFFSET)
161#define pfn_to_page(pfn) ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
162#define pfn_valid(pfn) ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
163
164#define virt_to_page(kaddr) (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
165#define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
166
167#define PHYS_TO_NID(addr) (0)
168
169#else /* CONFIG_DISCONTIGMEM */
170
171/*
172 * This is more complex. We have a set of mem_map arrays spread
173 * around in memory.
174 */
175#include <linux/numa.h>
176
177#define page_to_pfn(page) \
178 (( (page) - page_zone(page)->zone_mem_map) \
179 + page_zone(page)->zone_start_pfn)
180
181#define pfn_to_page(pfn) \
182 (PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
183
184#define pfn_valid(pfn) \
185 ({ \
186 unsigned int nid = PFN_TO_NID(pfn); \
187 int valid = nid < MAX_NUMNODES; \
188 if (valid) { \
189 pg_data_t *node = NODE_DATA(nid); \
190 valid = (pfn - node->node_start_pfn) < \
191 node->node_spanned_pages; \
192 } \
193 valid; \
194 })
195
196#define virt_to_page(kaddr) \
197 (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
198
199#define virt_addr_valid(kaddr) (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
200
201/*
202 * Common discontigmem stuff.
203 * PHYS_TO_NID is used by the ARM kernel/setup.c
204 */
205#define PHYS_TO_NID(addr) PFN_TO_NID((addr) >> PAGE_SHIFT)
206
207#endif /* !CONFIG_DISCONTIGMEM */
208
209/*
210 * For BIO. "will die". Kill me when bio_to_phys() and bvec_to_phys() die.
211 */
212#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
213
214/*
215 * Optional device DMA address remapping. Do _not_ use directly!
216 * We should really eliminate virt_to_bus() here - it's deprecated.
217 */
218#ifndef __arch_page_to_dma
219#define page_to_dma(dev, page) ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
220#define dma_to_virt(dev, addr) ((void *)__bus_to_virt(addr))
221#define virt_to_dma(dev, addr) ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
222#else
223#define page_to_dma(dev, page) (__arch_page_to_dma(dev, page))
224#define dma_to_virt(dev, addr) (__arch_dma_to_virt(dev, addr))
225#define virt_to_dma(dev, addr) (__arch_virt_to_dma(dev, addr))
226#endif
227
228#endif
229
230#endif