page.h

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/* MN10300 Page table definitions
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */
#ifndef _ASM_PAGE_H
#define _ASM_PAGE_H

/* PAGE_SHIFT determines the page size */
#define PAGE_SHIFT  12

#ifndef __ASSEMBLY__
#define PAGE_SIZE   (1UL << PAGE_SHIFT)
#define PAGE_MASK   (~(PAGE_SIZE - 1))
#else
#define PAGE_SIZE   +(1 << PAGE_SHIFT)  /* unary plus marks an
                         * immediate val not an addr */
#define PAGE_MASK   +(~(PAGE_SIZE - 1))
#endif

#ifdef __KERNEL__
#ifndef __ASSEMBLY__

#define clear_page(page)    memset((void *)(page), 0, PAGE_SIZE)
#define copy_page(to, from) memcpy((void *)(to), (void *)(from), PAGE_SIZE)

#define clear_user_page(addr, vaddr, page)  clear_page(addr)
#define copy_user_page(vto, vfrom, vaddr, to)   copy_page(vto, vfrom)

/*
 * These are used to make use of C type-checking..
 */
typedef struct { unsigned long pte; } pte_t;
typedef struct { unsigned long pgd; } pgd_t;
typedef struct { unsigned long pgprot; } pgprot_t;
typedef struct page *pgtable_t;

#define PTE_MASK    PAGE_MASK
#define HPAGE_SHIFT 22

#ifdef CONFIG_HUGETLB_PAGE
#define HPAGE_SIZE      ((1UL) << HPAGE_SHIFT)
#define HPAGE_MASK      (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER  (HPAGE_SHIFT - PAGE_SHIFT)
#endif

#define pte_val(x)  ((x).pte)
#define pgd_val(x)  ((x).pgd)
#define pgprot_val(x)   ((x).pgprot)

#define __pte(x)    ((pte_t) { (x) })
#define __pgd(x)    ((pgd_t) { (x) })
#define __pgprot(x) ((pgprot_t) { (x) })

#include <asm-generic/pgtable-nopmd.h>

#endif /* !__ASSEMBLY__ */

/*
 * This handles the memory map.. We could make this a config
 * option, but too many people screw it up, and too few need
 * it.
 *
 * A __PAGE_OFFSET of 0xC0000000 means that the kernel has
 * a virtual address space of one gigabyte, which limits the
 * amount of physical memory you can use to about 950MB.
 */

#ifndef __ASSEMBLY__

/* Pure 2^n version of get_order */
static inline int get_order(unsigned long size) __attribute__((const));
static inline int get_order(unsigned long size)
{
    int order;

    size = (size - 1) >> (PAGE_SHIFT - 1);
    order = -1;
    do {
        size >>= 1;
        order++;
    } while (size);
    return order;
}

#endif /* __ASSEMBLY__ */

#include <asm/page_offset.h>

#define __PAGE_OFFSET       (PAGE_OFFSET_RAW)
#define PAGE_OFFSET     ((unsigned long) __PAGE_OFFSET)

/*
 * main RAM and kernel working space are coincident at 0x90000000, but to make
 * life more interesting, there's also an uncached virtual shadow at 0xb0000000
 * - these mappings are fixed in the MMU
 */
#define __pfn_disp      (CONFIG_KERNEL_RAM_BASE_ADDRESS >> PAGE_SHIFT)

#define __pa(x)         ((unsigned long)(x))
#define __va(x)         ((void *)(unsigned long)(x))
#define pfn_to_kaddr(pfn)   __va((pfn) << PAGE_SHIFT)
#define pfn_to_page(pfn)    (mem_map + ((pfn) - __pfn_disp))
#define page_to_pfn(page)   ((unsigned long)((page) - mem_map) + __pfn_disp)

#define pfn_valid(pfn)                  \
({                          \
    unsigned long __pfn = (pfn) - __pfn_disp;   \
    __pfn < max_mapnr;              \
})

#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
#define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
#define page_to_phys(page)  (page_to_pfn(page) << PAGE_SHIFT)

#define VM_DATA_DEFAULT_FLAGS \
    (VM_READ | VM_WRITE | \
    ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) | \
         VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)

#endif /* __KERNEL__ */

#endif /* _ASM_PAGE_H */