Messages in this thread Patch in this message | | | From | Sonic Zhang <> | Subject | [PATCH] mm:page.h: Calculate virt_to_page and page_to_virt via predefined macro. | Date | Tue, 23 Aug 2011 14:58:26 +0800 |
| |
From: Sonic Zhang <sonic.zhang@analog.com>
In NOMMU architecture, 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> --- include/asm-generic/page.h | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/include/asm-generic/page.h b/include/asm-generic/page.h index 75fec18..96a1dc3 100644 --- a/include/asm-generic/page.h +++ b/include/asm-generic/page.h @@ -79,8 +79,13 @@ extern unsigned long memory_end; #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT) #define pfn_to_virt(pfn) __va((pfn) << PAGE_SHIFT) +#if 0 #define virt_to_page(addr) (mem_map + (((unsigned long)(addr)-PAGE_OFFSET) >> PAGE_SHIFT)) #define page_to_virt(page) ((((page) - mem_map) << PAGE_SHIFT) + PAGE_OFFSET) +#endif +#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) -- 1.7.0.4
| |