arch/mips/include/asm/pgtable.h - maze/linux - Git at Google

 /*
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
  * Copyright (C) 2003 Ralf Baechle
  */
 #ifndef _ASM_PGTABLE_H
 #define _ASM_PGTABLE_H

 #ifdef CONFIG_32BIT
 #include <asm/pgtable-32.h>
 #endif
 #ifdef CONFIG_64BIT
 #include <asm/pgtable-64.h>
 #endif

 #include <asm/io.h>
 #include <asm/pgtable-bits.h>

 struct mm_struct;
 struct vm_area_struct;

 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _CACHE_CACHABLE_NONCOHERENT)
 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_WRITE | (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) | \
 				 _page_cachable_default)
 #define PAGE_COPY	__pgprot(_PAGE_PRESENT | (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) | \
 				 (kernel_uses_smartmips_rixi ?  _PAGE_NO_EXEC : 0) | _page_cachable_default)
 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) | \
 				 _page_cachable_default)
 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
 				 _PAGE_GLOBAL | _page_cachable_default)
 #define PAGE_USERIO	__pgprot(_PAGE_PRESENT | (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) | _PAGE_WRITE | \
 				 _page_cachable_default)
 #define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
 			__WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)

 /*
  * If _PAGE_NO_EXEC is not defined, we can't do page protection for
  * execute, and consider it to be the same as read. Also, write
  * permissions imply read permissions. This is the closest we can get
  * by reasonable means..
  */

 /*
  * Dummy values to fill the table in mmap.c
  * The real values will be generated at runtime
  */
 #define __P000 __pgprot(0)
 #define __P001 __pgprot(0)
 #define __P010 __pgprot(0)
 #define __P011 __pgprot(0)
 #define __P100 __pgprot(0)
 #define __P101 __pgprot(0)
 #define __P110 __pgprot(0)
 #define __P111 __pgprot(0)

 #define __S000 __pgprot(0)
 #define __S001 __pgprot(0)
 #define __S010 __pgprot(0)
 #define __S011 __pgprot(0)
 #define __S100 __pgprot(0)
 #define __S101 __pgprot(0)
 #define __S110 __pgprot(0)
 #define __S111 __pgprot(0)

 extern unsigned long _page_cachable_default;

 /*
  * ZERO_PAGE is a global shared page that is always zero; used
  * for zero-mapped memory areas etc..
  */

 extern unsigned long empty_zero_page;
 extern unsigned long zero_page_mask;

 #define ZERO_PAGE(vaddr) \
 	(virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))

 #define is_zero_pfn is_zero_pfn
 static inline int is_zero_pfn(unsigned long pfn)
 {
 	extern unsigned long zero_pfn;
 	unsigned long offset_from_zero_pfn = pfn - zero_pfn;
 	return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
 }

 #define my_zero_pfn(addr)	page_to_pfn(ZERO_PAGE(addr))

 extern void paging_init(void);

 /*
  * Conversion functions: convert a page and protection to a page entry,
  * and a page entry and page directory to the page they refer to.
  */
 #define pmd_phys(pmd)		virt_to_phys((void *)pmd_val(pmd))
 #define pmd_page(pmd)		(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
 #define pmd_page_vaddr(pmd)	pmd_val(pmd)

 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)

 #define pte_none(pte)		(!(((pte).pte_low | (pte).pte_high) & ~_PAGE_GLOBAL))
 #define pte_present(pte)	((pte).pte_low & _PAGE_PRESENT)

 static inline void set_pte(pte_t *ptep, pte_t pte)
 {
 	ptep->pte_high = pte.pte_high;
 	smp_wmb();
 	ptep->pte_low = pte.pte_low;
 	//printk("pte_high %x pte_low %x\n", ptep->pte_high, ptep->pte_low);

 	if (pte.pte_low & _PAGE_GLOBAL) {
 		pte_t *buddy = ptep_buddy(ptep);
 		/*
 		 * Make sure the buddy is global too (if it's !none,
 		 * it better already be global)
 		 */
 		if (pte_none(*buddy)) {
 			buddy->pte_low  |= _PAGE_GLOBAL;
 			buddy->pte_high |= _PAGE_GLOBAL;
 		}
 	}
 }
 #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)

 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 {
 	pte_t null = __pte(0);

 	/* Preserve global status for the pair */
 	if (ptep_buddy(ptep)->pte_low & _PAGE_GLOBAL)
 		null.pte_low = null.pte_high = _PAGE_GLOBAL;

 	set_pte_at(mm, addr, ptep, null);
 }
 #else

 #define pte_none(pte)		(!(pte_val(pte) & ~_PAGE_GLOBAL))
 #define pte_present(pte)	(pte_val(pte) & _PAGE_PRESENT)

 /*
  * Certain architectures need to do special things when pte's
  * within a page table are directly modified.  Thus, the following
  * hook is made available.
  */
 static inline void set_pte(pte_t *ptep, pte_t pteval)
 {
 	*ptep = pteval;
 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
 	if (pte_val(pteval) & _PAGE_GLOBAL) {
 		pte_t *buddy = ptep_buddy(ptep);
 		/*
 		 * Make sure the buddy is global too (if it's !none,
 		 * it better already be global)
 		 */
 		if (pte_none(*buddy))
 			pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL;
 	}
 #endif
 }
 #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)

 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 {
 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
 	/* Preserve global status for the pair */
 	if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
 		set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
 	else
 #endif
 		set_pte_at(mm, addr, ptep, __pte(0));
 }
 #endif

 /*
  * (pmds are folded into puds so this doesn't get actually called,
  * but the define is needed for a generic inline function.)
  */
 #define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)

 #ifndef __PAGETABLE_PMD_FOLDED
 /*
  * (puds are folded into pgds so this doesn't get actually called,
  * but the define is needed for a generic inline function.)
  */
 #define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while(0)
 #endif

 #define PGD_T_LOG2	(__builtin_ffs(sizeof(pgd_t)) - 1)
 #define PMD_T_LOG2	(__builtin_ffs(sizeof(pmd_t)) - 1)
 #define PTE_T_LOG2	(__builtin_ffs(sizeof(pte_t)) - 1)

 /*
  * We used to declare this array with size but gcc 3.3 and older are not able
  * to find that this expression is a constant, so the size is dropped.
  */
 extern pgd_t swapper_pg_dir[];

 /*
  * The following only work if pte_present() is true.
  * Undefined behaviour if not..
  */
 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
 static inline int pte_write(pte_t pte)	{ return pte.pte_low & _PAGE_WRITE; }
 static inline int pte_dirty(pte_t pte)	{ return pte.pte_low & _PAGE_MODIFIED; }
 static inline int pte_young(pte_t pte)	{ return pte.pte_low & _PAGE_ACCESSED; }
 static inline int pte_file(pte_t pte)	{ return pte.pte_low & _PAGE_FILE; }

 static inline pte_t pte_wrprotect(pte_t pte)
 {
 	pte.pte_low  &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
 	pte.pte_high &= ~_PAGE_SILENT_WRITE;
 	return pte;
 }

 static inline pte_t pte_mkclean(pte_t pte)
 {
 	pte.pte_low  &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
 	pte.pte_high &= ~_PAGE_SILENT_WRITE;
 	return pte;
 }

 static inline pte_t pte_mkold(pte_t pte)
 {
 	pte.pte_low  &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ);
 	pte.pte_high &= ~_PAGE_SILENT_READ;
 	return pte;
 }

 static inline pte_t pte_mkwrite(pte_t pte)
 {
 	pte.pte_low |= _PAGE_WRITE;
 	if (pte.pte_low & _PAGE_MODIFIED) {
 		pte.pte_low  |= _PAGE_SILENT_WRITE;
 		pte.pte_high |= _PAGE_SILENT_WRITE;
 	}
 	return pte;
 }

 static inline pte_t pte_mkdirty(pte_t pte)
 {
 	pte.pte_low |= _PAGE_MODIFIED;
 	if (pte.pte_low & _PAGE_WRITE) {
 		pte.pte_low  |= _PAGE_SILENT_WRITE;
 		pte.pte_high |= _PAGE_SILENT_WRITE;
 	}
 	return pte;
 }

 static inline pte_t pte_mkyoung(pte_t pte)
 {
 	pte.pte_low |= _PAGE_ACCESSED;
 	if (pte.pte_low & _PAGE_READ) {
 		pte.pte_low  |= _PAGE_SILENT_READ;
 		pte.pte_high |= _PAGE_SILENT_READ;
 	}
 	return pte;
 }
 #else
 static inline int pte_write(pte_t pte)	{ return pte_val(pte) & _PAGE_WRITE; }
 static inline int pte_dirty(pte_t pte)	{ return pte_val(pte) & _PAGE_MODIFIED; }
 static inline int pte_young(pte_t pte)	{ return pte_val(pte) & _PAGE_ACCESSED; }
 static inline int pte_file(pte_t pte)	{ return pte_val(pte) & _PAGE_FILE; }

 static inline pte_t pte_wrprotect(pte_t pte)
 {
 	pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
 	return pte;
 }

 static inline pte_t pte_mkclean(pte_t pte)
 {
 	pte_val(pte) &= ~(_PAGE_MODIFIED|_PAGE_SILENT_WRITE);
 	return pte;
 }

 static inline pte_t pte_mkold(pte_t pte)
 {
 	pte_val(pte) &= ~(_PAGE_ACCESSED|_PAGE_SILENT_READ);
 	return pte;
 }

 static inline pte_t pte_mkwrite(pte_t pte)
 {
 	pte_val(pte) |= _PAGE_WRITE;
 	if (pte_val(pte) & _PAGE_MODIFIED)
 		pte_val(pte) |= _PAGE_SILENT_WRITE;
 	return pte;
 }

 static inline pte_t pte_mkdirty(pte_t pte)
 {
 	pte_val(pte) |= _PAGE_MODIFIED;
 	if (pte_val(pte) & _PAGE_WRITE)
 		pte_val(pte) |= _PAGE_SILENT_WRITE;
 	return pte;
 }

 static inline pte_t pte_mkyoung(pte_t pte)
 {
 	pte_val(pte) |= _PAGE_ACCESSED;
 	if (kernel_uses_smartmips_rixi) {
 		if (!(pte_val(pte) & _PAGE_NO_READ))
 			pte_val(pte) |= _PAGE_SILENT_READ;
 	} else {
 		if (pte_val(pte) & _PAGE_READ)
 			pte_val(pte) |= _PAGE_SILENT_READ;
 	}
 	return pte;
 }

 #ifdef _PAGE_HUGE
 static inline int pte_huge(pte_t pte)	{ return pte_val(pte) & _PAGE_HUGE; }

 static inline pte_t pte_mkhuge(pte_t pte)
 {
 	pte_val(pte) |= _PAGE_HUGE;
 	return pte;
 }
 #endif /* _PAGE_HUGE */
 #endif
 static inline int pte_special(pte_t pte)	{ return 0; }
 static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }

 /*
  * Macro to make mark a page protection value as "uncacheable".  Note
  * that "protection" is really a misnomer here as the protection value
  * contains the memory attribute bits, dirty bits, and various other
  * bits as well.
  */
 #define pgprot_noncached pgprot_noncached

 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 {
 	unsigned long prot = pgprot_val(_prot);

 	prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;

 	return __pgprot(prot);
 }

 /*
  * Conversion functions: convert a page and protection to a page entry,
  * and a page entry and page directory to the page they refer to.
  */
 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))

 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 {
 	pte.pte_low  &= _PAGE_CHG_MASK;
 	pte.pte_high &= ~0x3f;
 	pte.pte_low  |= pgprot_val(newprot);
 	pte.pte_high |= pgprot_val(newprot) & 0x3f;
 	return pte;
 }
 #else
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 {
 	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
 }
 #endif


 extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
 	pte_t pte);
 extern void __update_cache(struct vm_area_struct *vma, unsigned long address,
 	pte_t pte);

 static inline void update_mmu_cache(struct vm_area_struct *vma,
 	unsigned long address, pte_t *ptep)
 {
 	pte_t pte = *ptep;
 	__update_tlb(vma, address, pte);
 	__update_cache(vma, address, pte);
 }

 #define kern_addr_valid(addr)	(1)

 #ifdef CONFIG_64BIT_PHYS_ADDR
 extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot);

 static inline int io_remap_pfn_range(struct vm_area_struct *vma,
 		unsigned long vaddr,
 		unsigned long pfn,
 		unsigned long size,
 		pgprot_t prot)
 {
 	phys_t phys_addr_high = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
 	return remap_pfn_range(vma, vaddr, phys_addr_high >> PAGE_SHIFT, size, prot);
 }
 #else
 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot)		\
 		remap_pfn_range(vma, vaddr, pfn, size, prot)
 #endif

 #include <asm-generic/pgtable.h>

 /*
  * uncached accelerated TLB map for video memory access
  */
 #ifdef CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED
 #define __HAVE_PHYS_MEM_ACCESS_PROT

 struct file;
 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 		unsigned long size, pgprot_t vma_prot);
 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
 		unsigned long size, pgprot_t *vma_prot);
 #endif

 /*
  * We provide our own get_unmapped area to cope with the virtual aliasing
  * constraints placed on us by the cache architecture.
  */
 #define HAVE_ARCH_UNMAPPED_AREA

 /*
  * No page table caches to initialise
  */
 #define pgtable_cache_init()	do { } while (0)

 #endif /* _ASM_PGTABLE_H */
	/*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*
	* Copyright (C) 2003 Ralf Baechle
	*/
	#ifndef _ASM_PGTABLE_H
	#define _ASM_PGTABLE_H

	#ifdef CONFIG_32BIT
	#include <asm/pgtable-32.h>
	#endif
	#ifdef CONFIG_64BIT
	#include <asm/pgtable-64.h>
	#endif

	#include <asm/io.h>
	#include <asm/pgtable-bits.h>

	struct mm_struct;
	struct vm_area_struct;

	#define PAGE_NONE __pgprot(_PAGE_PRESENT \| _CACHE_CACHABLE_NONCOHERENT)
	#define PAGE_SHARED __pgprot(_PAGE_PRESENT \| _PAGE_WRITE \| (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) \| \
	_page_cachable_default)
	#define PAGE_COPY __pgprot(_PAGE_PRESENT \| (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) \| \
	(kernel_uses_smartmips_rixi ? _PAGE_NO_EXEC : 0) \| _page_cachable_default)
	#define PAGE_READONLY __pgprot(_PAGE_PRESENT \| (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) \| \
	_page_cachable_default)
	#define PAGE_KERNEL __pgprot(_PAGE_PRESENT \| __READABLE \| __WRITEABLE \| \
	_PAGE_GLOBAL \| _page_cachable_default)
	#define PAGE_USERIO __pgprot(_PAGE_PRESENT \| (kernel_uses_smartmips_rixi ? 0 : _PAGE_READ) \| _PAGE_WRITE \| \
	_page_cachable_default)
	#define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT \| __READABLE \| \
	__WRITEABLE \| _PAGE_GLOBAL \| _CACHE_UNCACHED)

	/*
	* If _PAGE_NO_EXEC is not defined, we can't do page protection for
	* execute, and consider it to be the same as read. Also, write
	* permissions imply read permissions. This is the closest we can get
	* by reasonable means..
	*/

	/*
	* Dummy values to fill the table in mmap.c
	* The real values will be generated at runtime
	*/
	#define __P000 __pgprot(0)
	#define __P001 __pgprot(0)
	#define __P010 __pgprot(0)
	#define __P011 __pgprot(0)
	#define __P100 __pgprot(0)
	#define __P101 __pgprot(0)
	#define __P110 __pgprot(0)
	#define __P111 __pgprot(0)

	#define __S000 __pgprot(0)
	#define __S001 __pgprot(0)
	#define __S010 __pgprot(0)
	#define __S011 __pgprot(0)
	#define __S100 __pgprot(0)
	#define __S101 __pgprot(0)
	#define __S110 __pgprot(0)
	#define __S111 __pgprot(0)

	extern unsigned long _page_cachable_default;

	/*
	* ZERO_PAGE is a global shared page that is always zero; used
	* for zero-mapped memory areas etc..
	*/

	extern unsigned long empty_zero_page;
	extern unsigned long zero_page_mask;

	#define ZERO_PAGE(vaddr) \
	(virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))

	#define is_zero_pfn is_zero_pfn
	static inline int is_zero_pfn(unsigned long pfn)
	{
	extern unsigned long zero_pfn;
	unsigned long offset_from_zero_pfn = pfn - zero_pfn;
	return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
	}

	#define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr))

	extern void paging_init(void);

	/*
	* Conversion functions: convert a page and protection to a page entry,
	* and a page entry and page directory to the page they refer to.
	*/
	#define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd))
	#define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
	#define pmd_page_vaddr(pmd) pmd_val(pmd)

	#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)

	#define pte_none(pte) (!(((pte).pte_low \| (pte).pte_high) & ~_PAGE_GLOBAL))
	#define pte_present(pte) ((pte).pte_low & _PAGE_PRESENT)

	static inline void set_pte(pte_t *ptep, pte_t pte)
	{
	ptep->pte_high = pte.pte_high;
	smp_wmb();
	ptep->pte_low = pte.pte_low;
	//printk("pte_high %x pte_low %x\n", ptep->pte_high, ptep->pte_low);

	if (pte.pte_low & _PAGE_GLOBAL) {
	pte_t *buddy = ptep_buddy(ptep);
	/*
	* Make sure the buddy is global too (if it's !none,
	* it better already be global)
	*/
	if (pte_none(*buddy)) {
	buddy->pte_low \|= _PAGE_GLOBAL;
	buddy->pte_high \|= _PAGE_GLOBAL;
	}
	}
	}
	#define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)

	static inline void pte_clear(struct mm_struct mm, unsigned long addr, pte_t ptep)
	{
	pte_t null = __pte(0);

	/* Preserve global status for the pair */
	if (ptep_buddy(ptep)->pte_low & _PAGE_GLOBAL)
	null.pte_low = null.pte_high = _PAGE_GLOBAL;

	set_pte_at(mm, addr, ptep, null);
	}
	#else

	#define pte_none(pte) (!(pte_val(pte) & ~_PAGE_GLOBAL))
	#define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT)

	/*
	* Certain architectures need to do special things when pte's
	* within a page table are directly modified. Thus, the following
	* hook is made available.
	*/
	static inline void set_pte(pte_t *ptep, pte_t pteval)
	{
	*ptep = pteval;
	#if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
	if (pte_val(pteval) & _PAGE_GLOBAL) {
	pte_t *buddy = ptep_buddy(ptep);
	/*
	* Make sure the buddy is global too (if it's !none,
	* it better already be global)
	*/
	if (pte_none(*buddy))
	pte_val(buddy) = pte_val(buddy) \| _PAGE_GLOBAL;
	}
	#endif
	}
	#define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)

	static inline void pte_clear(struct mm_struct mm, unsigned long addr, pte_t ptep)
	{
	#if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
	/* Preserve global status for the pair */
	if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
	set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
	else
	#endif
	set_pte_at(mm, addr, ptep, __pte(0));
	}
	#endif

	/*
	* (pmds are folded into puds so this doesn't get actually called,
	* but the define is needed for a generic inline function.)
	*/
	#define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)

	#ifndef __PAGETABLE_PMD_FOLDED
	/*
	* (puds are folded into pgds so this doesn't get actually called,
	* but the define is needed for a generic inline function.)
	*/
	#define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while(0)
	#endif

	#define PGD_T_LOG2 (__builtin_ffs(sizeof(pgd_t)) - 1)
	#define PMD_T_LOG2 (__builtin_ffs(sizeof(pmd_t)) - 1)
	#define PTE_T_LOG2 (__builtin_ffs(sizeof(pte_t)) - 1)

	/*
	* We used to declare this array with size but gcc 3.3 and older are not able
	* to find that this expression is a constant, so the size is dropped.
	*/
	extern pgd_t swapper_pg_dir[];

	/*
	* The following only work if pte_present() is true.
	* Undefined behaviour if not..
	*/
	#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
	static inline int pte_write(pte_t pte) { return pte.pte_low & _PAGE_WRITE; }
	static inline int pte_dirty(pte_t pte) { return pte.pte_low & _PAGE_MODIFIED; }
	static inline int pte_young(pte_t pte) { return pte.pte_low & _PAGE_ACCESSED; }
	static inline int pte_file(pte_t pte) { return pte.pte_low & _PAGE_FILE; }

	static inline pte_t pte_wrprotect(pte_t pte)
	{
	pte.pte_low &= ~(_PAGE_WRITE \| _PAGE_SILENT_WRITE);
	pte.pte_high &= ~_PAGE_SILENT_WRITE;
	return pte;
	}

	static inline pte_t pte_mkclean(pte_t pte)
	{
	pte.pte_low &= ~(_PAGE_MODIFIED \| _PAGE_SILENT_WRITE);
	pte.pte_high &= ~_PAGE_SILENT_WRITE;
	return pte;
	}

	static inline pte_t pte_mkold(pte_t pte)
	{
	pte.pte_low &= ~(_PAGE_ACCESSED \| _PAGE_SILENT_READ);
	pte.pte_high &= ~_PAGE_SILENT_READ;
	return pte;
	}

	static inline pte_t pte_mkwrite(pte_t pte)
	{
	pte.pte_low \|= _PAGE_WRITE;
	if (pte.pte_low & _PAGE_MODIFIED) {
	pte.pte_low \|= _PAGE_SILENT_WRITE;
	pte.pte_high \|= _PAGE_SILENT_WRITE;
	}
	return pte;
	}

	static inline pte_t pte_mkdirty(pte_t pte)
	{
	pte.pte_low \|= _PAGE_MODIFIED;
	if (pte.pte_low & _PAGE_WRITE) {
	pte.pte_low \|= _PAGE_SILENT_WRITE;
	pte.pte_high \|= _PAGE_SILENT_WRITE;
	}
	return pte;
	}

	static inline pte_t pte_mkyoung(pte_t pte)
	{
	pte.pte_low \|= _PAGE_ACCESSED;
	if (pte.pte_low & _PAGE_READ) {
	pte.pte_low \|= _PAGE_SILENT_READ;
	pte.pte_high \|= _PAGE_SILENT_READ;
	}
	return pte;
	}
	#else
	static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
	static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_MODIFIED; }
	static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
	static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }

	static inline pte_t pte_wrprotect(pte_t pte)
	{
	pte_val(pte) &= ~(_PAGE_WRITE \| _PAGE_SILENT_WRITE);
	return pte;
	}

	static inline pte_t pte_mkclean(pte_t pte)
	{
	pte_val(pte) &= ~(_PAGE_MODIFIED\|_PAGE_SILENT_WRITE);
	return pte;
	}

	static inline pte_t pte_mkold(pte_t pte)
	{
	pte_val(pte) &= ~(_PAGE_ACCESSED\|_PAGE_SILENT_READ);
	return pte;
	}

	static inline pte_t pte_mkwrite(pte_t pte)
	{
	pte_val(pte) \|= _PAGE_WRITE;
	if (pte_val(pte) & _PAGE_MODIFIED)
	pte_val(pte) \|= _PAGE_SILENT_WRITE;
	return pte;
	}

	static inline pte_t pte_mkdirty(pte_t pte)
	{
	pte_val(pte) \|= _PAGE_MODIFIED;
	if (pte_val(pte) & _PAGE_WRITE)
	pte_val(pte) \|= _PAGE_SILENT_WRITE;
	return pte;
	}

	static inline pte_t pte_mkyoung(pte_t pte)
	{
	pte_val(pte) \|= _PAGE_ACCESSED;
	if (kernel_uses_smartmips_rixi) {
	if (!(pte_val(pte) & _PAGE_NO_READ))
	pte_val(pte) \|= _PAGE_SILENT_READ;
	} else {
	if (pte_val(pte) & _PAGE_READ)
	pte_val(pte) \|= _PAGE_SILENT_READ;
	}
	return pte;
	}

	#ifdef _PAGE_HUGE
	static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_HUGE; }

	static inline pte_t pte_mkhuge(pte_t pte)
	{
	pte_val(pte) \|= _PAGE_HUGE;
	return pte;
	}
	#endif /* _PAGE_HUGE */
	#endif
	static inline int pte_special(pte_t pte) { return 0; }
	static inline pte_t pte_mkspecial(pte_t pte) { return pte; }

	/*
	* Macro to make mark a page protection value as "uncacheable". Note
	* that "protection" is really a misnomer here as the protection value
	* contains the memory attribute bits, dirty bits, and various other
	* bits as well.
	*/
	#define pgprot_noncached pgprot_noncached

	static inline pgprot_t pgprot_noncached(pgprot_t _prot)
	{
	unsigned long prot = pgprot_val(_prot);

	prot = (prot & ~_CACHE_MASK) \| _CACHE_UNCACHED;

	return __pgprot(prot);
	}

	/*
	* Conversion functions: convert a page and protection to a page entry,
	* and a page entry and page directory to the page they refer to.
	*/
	#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))

	#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
	static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
	{
	pte.pte_low &= _PAGE_CHG_MASK;
	pte.pte_high &= ~0x3f;
	pte.pte_low \|= pgprot_val(newprot);
	pte.pte_high \|= pgprot_val(newprot) & 0x3f;
	return pte;
	}
	#else
	static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
	{
	return __pte((pte_val(pte) & _PAGE_CHG_MASK) \| pgprot_val(newprot));
	}
	#endif


	extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
	pte_t pte);
	extern void __update_cache(struct vm_area_struct *vma, unsigned long address,
	pte_t pte);

	static inline void update_mmu_cache(struct vm_area_struct *vma,
	unsigned long address, pte_t *ptep)
	{
	pte_t pte = *ptep;
	__update_tlb(vma, address, pte);
	__update_cache(vma, address, pte);
	}

	#define kern_addr_valid(addr) (1)

	#ifdef CONFIG_64BIT_PHYS_ADDR
	extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot);

	static inline int io_remap_pfn_range(struct vm_area_struct *vma,
	unsigned long vaddr,
	unsigned long pfn,
	unsigned long size,
	pgprot_t prot)
	{
	phys_t phys_addr_high = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
	return remap_pfn_range(vma, vaddr, phys_addr_high >> PAGE_SHIFT, size, prot);
	}
	#else
	#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
	remap_pfn_range(vma, vaddr, pfn, size, prot)
	#endif

	#include <asm-generic/pgtable.h>

	/*
	* uncached accelerated TLB map for video memory access
	*/
	#ifdef CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED
	#define __HAVE_PHYS_MEM_ACCESS_PROT

	struct file;
	pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
	unsigned long size, pgprot_t vma_prot);
	int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
	unsigned long size, pgprot_t *vma_prot);
	#endif

	/*
	* We provide our own get_unmapped area to cope with the virtual aliasing
	* constraints placed on us by the cache architecture.
	*/
	#define HAVE_ARCH_UNMAPPED_AREA

	/*
	* No page table caches to initialise
	*/
	#define pgtable_cache_init() do { } while (0)

	#endif /* _ASM_PGTABLE_H */