mirror of
https://github.com/torvalds/linux.git
synced 2024-11-15 00:21:59 +00:00
06d5e032ad
On NOMMU architectures, if physical memory doesn't start from 0, ARCH_PFN_OFFSET is defined to generate page index in mem_map array. Because virtual address is equal to physical address, PAGE_OFFSET is always 0. virt_to_page and page_to_virt should not index page by PAGE_OFFSET directly. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Cc: Greg Ungerer <gerg@snapgear.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
100 lines
2.4 KiB
C
100 lines
2.4 KiB
C
#ifndef __ASM_GENERIC_PAGE_H
|
|
#define __ASM_GENERIC_PAGE_H
|
|
/*
|
|
* Generic page.h implementation, for NOMMU architectures.
|
|
* This provides the dummy definitions for the memory management.
|
|
*/
|
|
|
|
#ifdef CONFIG_MMU
|
|
#error need to prove a real asm/page.h
|
|
#endif
|
|
|
|
|
|
/* PAGE_SHIFT determines the page size */
|
|
|
|
#define PAGE_SHIFT 12
|
|
#ifdef __ASSEMBLY__
|
|
#define PAGE_SIZE (1 << PAGE_SHIFT)
|
|
#else
|
|
#define PAGE_SIZE (1UL << PAGE_SHIFT)
|
|
#endif
|
|
#define PAGE_MASK (~(PAGE_SIZE-1))
|
|
|
|
#include <asm/setup.h>
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#define get_user_page(vaddr) __get_free_page(GFP_KERNEL)
|
|
#define free_user_page(page, addr) free_page(addr)
|
|
|
|
#define clear_page(page) memset((page), 0, PAGE_SIZE)
|
|
#define copy_page(to,from) memcpy((to), (from), PAGE_SIZE)
|
|
|
|
#define clear_user_page(page, vaddr, pg) clear_page(page)
|
|
#define copy_user_page(to, from, vaddr, pg) copy_page(to, from)
|
|
|
|
/*
|
|
* These are used to make use of C type-checking..
|
|
*/
|
|
typedef struct {
|
|
unsigned long pte;
|
|
} pte_t;
|
|
typedef struct {
|
|
unsigned long pmd[16];
|
|
} pmd_t;
|
|
typedef struct {
|
|
unsigned long pgd;
|
|
} pgd_t;
|
|
typedef struct {
|
|
unsigned long pgprot;
|
|
} pgprot_t;
|
|
typedef struct page *pgtable_t;
|
|
|
|
#define pte_val(x) ((x).pte)
|
|
#define pmd_val(x) ((&x)->pmd[0])
|
|
#define pgd_val(x) ((x).pgd)
|
|
#define pgprot_val(x) ((x).pgprot)
|
|
|
|
#define __pte(x) ((pte_t) { (x) } )
|
|
#define __pmd(x) ((pmd_t) { (x) } )
|
|
#define __pgd(x) ((pgd_t) { (x) } )
|
|
#define __pgprot(x) ((pgprot_t) { (x) } )
|
|
|
|
extern unsigned long memory_start;
|
|
extern unsigned long memory_end;
|
|
|
|
#endif /* !__ASSEMBLY__ */
|
|
|
|
#ifdef CONFIG_KERNEL_RAM_BASE_ADDRESS
|
|
#define PAGE_OFFSET (CONFIG_KERNEL_RAM_BASE_ADDRESS)
|
|
#else
|
|
#define PAGE_OFFSET (0)
|
|
#endif
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
|
|
#define __pa(x) ((unsigned long) (x) - PAGE_OFFSET)
|
|
|
|
#define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
|
|
#define pfn_to_virt(pfn) __va((pfn) << PAGE_SHIFT)
|
|
|
|
#define virt_to_page(addr) pfn_to_page(virt_to_pfn(addr))
|
|
#define page_to_virt(page) pfn_to_virt(page_to_pfn(page))
|
|
|
|
#ifndef page_to_phys
|
|
#define page_to_phys(page) ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
|
|
#endif
|
|
|
|
#define pfn_valid(pfn) ((pfn) < max_mapnr)
|
|
|
|
#define virt_addr_valid(kaddr) (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
|
|
((void *)(kaddr) < (void *)memory_end))
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
#include <asm-generic/memory_model.h>
|
|
#include <asm-generic/getorder.h>
|
|
|
|
#endif /* __ASM_GENERIC_PAGE_H */
|