2 * linux/include/asm-arm/memory.h
4 * Copyright (C) 2000-2002 Russell King
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.
10 * Note: this file should not be included by non-asm/.h files
12 #ifndef __ASM_ARM_MEMORY_H
13 #define __ASM_ARM_MEMORY_H
16 * Allow for constants defined here to be used from assembly code
17 * by prepending the UL suffix only with actual C code compilation.
25 #include <linux/config.h>
26 #include <linux/compiler.h>
27 #include <asm/arch/memory.h>
31 * TASK_SIZE - the maximum size of a user space task.
32 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
34 #define TASK_SIZE UL(0xbf000000)
35 #define TASK_UNMAPPED_BASE UL(0x40000000)
39 * The maximum size of a 26-bit user space task.
41 #define TASK_SIZE_26 UL(0x04000000)
47 #define PAGE_OFFSET UL(0xc0000000)
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.
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)
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.
64 #define MODULE_END (PAGE_OFFSET)
65 #define MODULE_START (MODULE_END - 16*1048576)
67 #if TASK_SIZE > MODULE_START
68 #error Top of user space clashes with start of module space
74 * The DMA mask corresponding to the maximum bus address allocatable
75 * using GFP_DMA. The default here places no restriction on DMA
76 * allocations. This must be the smallest DMA mask in the system,
77 * so a successful GFP_DMA allocation will always satisfy this.
79 #ifndef ISA_DMA_THRESHOLD
80 #define ISA_DMA_THRESHOLD (0xffffffffULL)
83 #ifndef arch_adjust_zones
84 #define arch_adjust_zones(node,size,holes) do { } while (0)
88 * PFNs are used to describe any physical page; this means
89 * PFN 0 == physical address 0.
91 * This is the PFN of the first RAM page in the kernel
92 * direct-mapped view. We assume this is the first page
93 * of RAM in the mem_map as well.
95 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
98 * These are *only* valid on the kernel direct mapped RAM memory.
99 * Note: Drivers should NOT use these. They are the wrong
100 * translation for translating DMA addresses. Use the driver
101 * DMA support - see dma-mapping.h.
103 static inline unsigned long virt_to_phys(void *x)
105 return __virt_to_phys((unsigned long)(x));
108 static inline void *phys_to_virt(unsigned long x)
110 return (void *)(__phys_to_virt((unsigned long)(x)));
114 * Drivers should NOT use these either.
116 #define __pa(x) __virt_to_phys((unsigned long)(x))
117 #define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
120 * Virtual <-> DMA view memory address translations
121 * Again, these are *only* valid on the kernel direct mapped RAM
122 * memory. Use of these is *deprecated* (and that doesn't mean
123 * use the __ prefixed forms instead.) See dma-mapping.h.
125 static inline __deprecated unsigned long virt_to_bus(void *x)
127 return __virt_to_bus((unsigned long)x);
130 static inline __deprecated void *bus_to_virt(unsigned long x)
132 return (void *)__bus_to_virt(x);
136 * Conversion between a struct page and a physical address.
138 * Note: when converting an unknown physical address to a
139 * struct page, the resulting pointer must be validated
140 * using VALID_PAGE(). It must return an invalid struct page
141 * for any physical address not corresponding to a system
144 * page_to_pfn(page) convert a struct page * to a PFN number
145 * pfn_to_page(pfn) convert a _valid_ PFN number to struct page *
146 * pfn_valid(pfn) indicates whether a PFN number is valid
148 * virt_to_page(k) convert a _valid_ virtual address to struct page *
149 * virt_addr_valid(k) indicates whether a virtual address is valid
151 #ifndef CONFIG_DISCONTIGMEM
153 #define page_to_pfn(page) (((page) - mem_map) + PHYS_PFN_OFFSET)
154 #define pfn_to_page(pfn) ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
155 #define pfn_valid(pfn) ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
157 #define virt_to_page(kaddr) (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
158 #define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
160 #define PHYS_TO_NID(addr) (0)
162 #else /* CONFIG_DISCONTIGMEM */
165 * This is more complex. We have a set of mem_map arrays spread
168 #include <linux/numa.h>
170 #define page_to_pfn(page) \
171 (( (page) - page_zone(page)->zone_mem_map) \
172 + page_zone(page)->zone_start_pfn)
174 #define pfn_to_page(pfn) \
175 (PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
177 #define pfn_valid(pfn) \
179 unsigned int nid = PFN_TO_NID(pfn); \
180 int valid = nid < MAX_NUMNODES; \
182 pg_data_t *node = NODE_DATA(nid); \
183 valid = (pfn - node->node_start_pfn) < \
184 node->node_spanned_pages; \
189 #define virt_to_page(kaddr) \
190 (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
192 #define virt_addr_valid(kaddr) (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
195 * Common discontigmem stuff.
196 * PHYS_TO_NID is used by the ARM kernel/setup.c
198 #define PHYS_TO_NID(addr) PFN_TO_NID((addr) >> PAGE_SHIFT)
200 #endif /* !CONFIG_DISCONTIGMEM */
203 * For BIO. "will die". Kill me when bio_to_phys() and bvec_to_phys() die.
205 #define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
208 * Optional device DMA address remapping. Do _not_ use directly!
209 * We should really eliminate virt_to_bus() here - it's deprecated.
211 #ifndef __arch_page_to_dma
212 #define page_to_dma(dev, page) ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
213 #define dma_to_virt(dev, addr) ((void *)__bus_to_virt(addr))
214 #define virt_to_dma(dev, addr) ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
216 #define page_to_dma(dev, page) (__arch_page_to_dma(dev, page))
217 #define dma_to_virt(dev, addr) (__arch_dma_to_virt(dev, addr))
218 #define virt_to_dma(dev, addr) (__arch_virt_to_dma(dev, addr))