root/include/linux/pfn.h

INCLUDED FROM

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_PFN_H_
   3 #define _LINUX_PFN_H_
   4 
   5 #ifndef __ASSEMBLY__
   6 #include <linux/types.h>
   7 
   8 /*
   9  * pfn_t: encapsulates a page-frame number that is optionally backed
  10  * by memmap (struct page).  Whether a pfn_t has a 'struct page'
  11  * backing is indicated by flags in the high bits of the value.
  12  */
  13 typedef struct {
  14         u64 val;
  15 } pfn_t;
  16 #endif
  17 
  18 #define PFN_ALIGN(x)    (((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
  19 #define PFN_UP(x)       (((x) + PAGE_SIZE-1) >> PAGE_SHIFT)
  20 #define PFN_DOWN(x)     ((x) >> PAGE_SHIFT)
  21 #define PFN_PHYS(x)     ((phys_addr_t)(x) << PAGE_SHIFT)
  22 #define PHYS_PFN(x)     ((unsigned long)((x) >> PAGE_SHIFT))
  23 
  24 #endif