linux/include/asm-powerpc/pgtable.h

#ifndef _ASM_POWERPC_PGTABLE_H
#define _ASM_POWERPC_PGTABLE_H
#ifdef __KERNEL__

#ifndef __ASSEMBLY__
#include <asm/processor.h>		/* For TASK_SIZE */
#include <asm/mmu.h>
#include <asm/page.h>
struct mm_struct;
#endif /* !__ASSEMBLY__ */

#if defined(CONFIG_PPC64)
#  include <asm/pgtable-ppc64.h>
#else
#  include <asm/pgtable-ppc32.h>
#endif

#ifndef __ASSEMBLY__
/*
 * ZERO_PAGE is a global shared page that is always zero: used
 * for zero-mapped memory areas etc..
 */
extern unsigned long empty_zero_page[];
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))

extern pgd_t swapper_pg_dir[];

extern void paging_init(void);

/*
 * kern_addr_valid is intended to indicate whether an address is a valid
 * kernel address.  Most 32-bit archs define it as always true (like this)
 * but most 64-bit archs actually perform a test.  What should we do here?
 */
#define kern_addr_valid(addr)	(1)

#define io_remap_pfn_range(vma, vaddr, pfn, size, prot)		\
		remap_pfn_range(vma, vaddr, pfn, size, prot)

#include <asm-generic/pgtable.h>
#endif /* __ASSEMBLY__ */

#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_PGTABLE_H */