diff options
Diffstat (limited to 'include/linux/pfn.h')
| -rw-r--r-- | include/linux/pfn.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/linux/pfn.h b/include/linux/pfn.h index 7646637221f3..2d8e49711b63 100644 --- a/include/linux/pfn.h +++ b/include/linux/pfn.h @@ -3,11 +3,21 @@ #ifndef __ASSEMBLY__ #include <linux/types.h> + +/* + * pfn_t: encapsulates a page-frame number that is optionally backed + * by memmap (struct page). Whether a pfn_t has a 'struct page' + * backing is indicated by flags in the high bits of the value. + */ +typedef struct { + unsigned long val; +} pfn_t; #endif #define PFN_ALIGN(x) (((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK) #define PFN_UP(x) (((x) + PAGE_SIZE-1) >> PAGE_SHIFT) #define PFN_DOWN(x) ((x) >> PAGE_SHIFT) #define PFN_PHYS(x) ((phys_addr_t)(x) << PAGE_SHIFT) +#define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT)) #endif |