memory.h
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/* * linux/include/asm-arm26/memory.h * * Copyright (C) 2000-2002 Russell King * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Note: this file should not be included by non-asm/.h files */#ifndef __ASM_ARM_MEMORY_H#define __ASM_ARM_MEMORY_H/* * User space: 26MB */#define TASK_SIZE (0x01a00000UL)/* * This decides where the kernel will search for a free chunk of vm * space during mmap's. */#define TASK_UNMAPPED_BASE (TASK_SIZE / 3)/* * Page offset: 32MB */#define PAGE_OFFSET (0x02000000UL)#define PHYS_OFFSET (0x02000000UL)#define PHYS_TO_NID(addr) (0)/* * PFNs are used to describe any physical page; this means * PFN 0 == physical address 0. * * This is the PFN of the first RAM page in the kernel * direct-mapped view. We assume this is the first page * of RAM in the mem_map as well. */#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)/* * These are *only* valid on the kernel direct mapped RAM memory. */static inline unsigned long virt_to_phys(void *x){ return (unsigned long)x;}static inline void *phys_to_virt(unsigned long x){ return (void *)((unsigned long)x);}#define __pa(x) (unsigned long)(x)#define __va(x) ((void *)(unsigned long)(x))/* * Virtual <-> DMA view memory address translations * Again, these are *only* valid on the kernel direct mapped RAM * memory. Use of these is *depreciated*. */#define virt_to_bus(x) ((unsigned long)(x))#define bus_to_virt(x) ((void *)((unsigned long)(x)))/* * Conversion between a struct page and a physical address. * * Note: when converting an unknown physical address to a * struct page, the resulting pointer must be validated * using VALID_PAGE(). It must return an invalid struct page * for any physical address not corresponding to a system * RAM address. * * page_to_pfn(page) convert a struct page * to a PFN number * pfn_to_page(pfn) convert a _valid_ PFN number to struct page * * pfn_valid(pfn) indicates whether a PFN number is valid * * virt_to_page(k) convert a _valid_ virtual address to struct page * * virt_addr_valid(k) indicates whether a virtual address is valid */#define page_to_pfn(page) (((page) - mem_map) + PHYS_PFN_OFFSET)#define pfn_to_page(pfn) ((mem_map + (pfn)) - PHYS_PFN_OFFSET)#define pfn_valid(pfn) ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))#define virt_to_page(kaddr) (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))#define virt_addr_valid(kaddr) ((int)(kaddr) >= PAGE_OFFSET && (int)(kaddr) < (unsigned long)high_memory)/* * For BIO. "will die". Kill me when bio_to_phys() and bvec_to_phys() die. */#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)/* * We should really eliminate virt_to_bus() here - it's depreciated. */#define page_to_bus(page) (page_address(page))#endif
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