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  • /*
     *  linux/include/asm-arm/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
    
    #if 0	/* XXX###XXX */
    
    #include <asm/arch/memory.h>
    
    /*
     * 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 __virt_to_phys((unsigned long)(x));
    }
    
    static inline void *phys_to_virt(unsigned long x)
    {
    	return (void *)(__phys_to_virt((unsigned long)(x)));
    }
    
    #define __pa(x)			__virt_to_phys((unsigned long)(x))
    #define __va(x)			((void *)__phys_to_virt((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)		(__virt_to_bus((unsigned long)(x)))
    #define bus_to_virt(x)		((void *)(__bus_to_virt((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
     */
    #ifndef CONFIG_DISCONTIGMEM
    
    #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)	((kaddr) >= PAGE_OFFSET && (kaddr) < (unsigned long)high_memory)
    
    #define PHYS_TO_NID(addr)	(0)
    
    #define VALID_PAGE(page)	((page - mem_map) < max_mapnr)
    
    #else
    
    /*
     * This is more complex.  We have a set of mem_map arrays spread
     * around in memory.
     */
    #define page_to_pfn(page)					\
    	(((page) - page_zone(page)->zone_mem_map)		\
    	  + (page_zone(page)->zone_start_paddr >> PAGE_SHIFT))
    
    #define pfn_to_page(pfn)					\
    	(PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
    
    #define pfn_valid(pfn)						\
      ({								\
    	unsigned int node = PFN_TO_NID(pfn);			\
    	struct pglist_data *nd = NODE_DATA(node);		\
    	((node < NR_NODES) &&					\
    	 ((pfn - (nd->node_start_paddr >> PAGE_SHIFT)) < nd->node_size));\
       })
    
    #define virt_to_page(kaddr)					\
    	(ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
    
    #define virt_addr_valid(kaddr)	(KVADDR_TO_NID(kaddr) < NR_NODES)
    
    /*
     * Common discontigmem stuff.
     *  PHYS_TO_NID is used by the ARM kernel/setup.c
     */
    #define PHYS_TO_NID(addr)	PFN_TO_NID((addr) >> PAGE_SHIFT)
    
    /*
     * 2.4 compatibility
     *
     * VALID_PAGE returns a non-zero value if given page pointer is valid.
     * This assumes all node's mem_maps are stored within the node they
     * refer to.  This is actually inherently buggy.
     */
    #define VALID_PAGE(page) \
    ({ unsigned int node = KVADDR_TO_NID(page); \
       ((node < NR_NODES) && \
         ((unsigned)((page) - NODE_MEM_MAP(node)) < NODE_DATA(node)->node_size)); \
    })
    
    #endif
    
    /*
     * We should really eliminate virt_to_bus() here - it's depreciated.
     */
    #define page_to_bus(page)	(virt_to_bus(page_address(page)))
    
    #endif	/* XXX###XXX */
    
    #endif	/* __ASM_ARM_MEMORY_H */