include/asm-i386/page.h

10786 #ifndef _I386_PAGE_H
10787 #define _I386_PAGE_H
10788 
10789 /* PAGE_SHIFT determines the page size */
10790 #define PAGE_SHIFT      12
10791 #define PAGE_SIZE       (1UL << PAGE_SHIFT)
10792 #define PAGE_MASK       (~(PAGE_SIZE-1))
10793 
10794 #ifdef __KERNEL__
10795 #ifndef __ASSEMBLY__
10796 
10797 #define STRICT_MM_TYPECHECKS
10798 
10799 #define clear_page(page)                                \
10800   memset((void *)(page), 0, PAGE_SIZE)
10801 #define copy_page(to,from)                              \
10802   memcpy((void *)(to), (void *)(from), PAGE_SIZE)
10803 
10804 #ifdef STRICT_MM_TYPECHECKS
10805 /* These are used to make use of C type-checking.. */
10806 typedef struct { unsigned long pte; } pte_t;
10807 typedef struct { unsigned long pmd; } pmd_t;
10808 typedef struct { unsigned long pgd; } pgd_t;
10809 typedef struct { unsigned long pgprot; } pgprot_t;
10810 
10811 #define pte_val(x)      ((x).pte)
10812 #define pmd_val(x)      ((x).pmd)
10813 #define pgd_val(x)      ((x).pgd)
10814 #define pgprot_val(x)   ((x).pgprot)
10815 
10816 #define __pte(x)        ((pte_t) { (x) } )
10817 #define __pmd(x)        ((pmd_t) { (x) } )
10818 #define __pgd(x)        ((pgd_t) { (x) } )
10819 #define __pgprot(x)     ((pgprot_t) { (x) } )
10820 
10821 #else
10822 /* .. while these make it easier on the compiler */
10823 typedef unsigned long pte_t;
10824 typedef unsigned long pmd_t;
10825 typedef unsigned long pgd_t;
10826 typedef unsigned long pgprot_t;
10827 
10828 #define pte_val(x)      (x)
10829 #define pmd_val(x)      (x)
10830 #define pgd_val(x)      (x)
10831 #define pgprot_val(x)   (x)
10832 
10833 #define __pte(x)        (x)
10834 #define __pmd(x)        (x)
10835 #define __pgd(x)        (x)
10836 #define __pgprot(x)     (x)
10837 
10838 #endif
10839 #endif /* !__ASSEMBLY__ */
10840 
10841 /* to align the pointer to the (next) page boundary */
10842 #define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)
10843 
10844 /* This handles the memory map.. We could make this a
10845  * config option, but too many people screw it up, and
10846  * too few need it.
10847  *
10848  * A __PAGE_OFFSET of 0xC0000000 means that the kernel
10849  * has a virtual address space of one gigabyte, which
10850  * limits the amount of physical memory you can use to
10851  * about 950MB. If you want to use more physical memory,
10852  * change this define.
10853  *
10854  * For example, if you have 2GB worth of physical memory,
10855  * you could change this define to 0x80000000, which
10856  * gives the kernel 2GB of virtual memory (enough to most
10857  * of your physical memory as the kernel needs a bit
10858  * extra for various io-memory mappings)
10859  *
10860  * IF YOU CHANGE THIS, PLEASE ALSO CHANGE
10861  *
10862  *      arch/i386/vmlinux.lds
10863  *
10864  * which has the same constant encoded..  */
10865 #define __PAGE_OFFSET           (0xC0000000)
10866 
10867 #define PAGE_OFFSET   ((unsigned long)__PAGE_OFFSET)
10868 #define __pa(x)       ((unsigned long)(x)-PAGE_OFFSET)
10869 #define __va(x)       ((void *)((unsigned long)(x) +    \
10870                                 PAGE_OFFSET))
10871 #define MAP_NR(addr)  (__pa(addr) >> PAGE_SHIFT)
10872 
10873 #endif /* __KERNEL__ */
10874 
10875 #endif /* _I386_PAGE_H */