pgtable.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  4 *
  5 * Derived from MIPS:
  6 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
  7 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
  8 */
  9#ifndef _ASM_PGTABLE_H
 10#define _ASM_PGTABLE_H
 11
 12#include <linux/compiler.h>
 13#include <asm/addrspace.h>
 14#include <asm/asm.h>
 15#include <asm/page.h>
 16#include <asm/pgtable-bits.h>
 17
 18#if CONFIG_PGTABLE_LEVELS == 2
 19#include <asm-generic/pgtable-nopmd.h>
 20#elif CONFIG_PGTABLE_LEVELS == 3
 21#include <asm-generic/pgtable-nopud.h>
 22#else
 23#include <asm-generic/pgtable-nop4d.h>
 24#endif
 25
 26#if CONFIG_PGTABLE_LEVELS == 2
 27#define PGDIR_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT - PTRLOG))
 28#elif CONFIG_PGTABLE_LEVELS == 3
 29#define PMD_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT - PTRLOG))
 30#define PMD_SIZE	(1UL << PMD_SHIFT)
 31#define PMD_MASK	(~(PMD_SIZE-1))
 32#define PGDIR_SHIFT	(PMD_SHIFT + (PAGE_SHIFT - PTRLOG))
 33#elif CONFIG_PGTABLE_LEVELS == 4
 34#define PMD_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT - PTRLOG))
 35#define PMD_SIZE	(1UL << PMD_SHIFT)
 36#define PMD_MASK	(~(PMD_SIZE-1))
 37#define PUD_SHIFT	(PMD_SHIFT + (PAGE_SHIFT - PTRLOG))
 38#define PUD_SIZE	(1UL << PUD_SHIFT)
 39#define PUD_MASK	(~(PUD_SIZE-1))
 40#define PGDIR_SHIFT	(PUD_SHIFT + (PAGE_SHIFT - PTRLOG))
 41#endif
 42
 43#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
 44#define PGDIR_MASK	(~(PGDIR_SIZE-1))
 45
 46#ifdef CONFIG_32BIT
 47#define VA_BITS		32
 48#else
 49#define VA_BITS		(PGDIR_SHIFT + (PAGE_SHIFT - PTRLOG))
 50#endif
 51
 52#define PTRS_PER_PGD	(PAGE_SIZE >> PTRLOG)
 53#if CONFIG_PGTABLE_LEVELS > 3
 54#define PTRS_PER_PUD	(PAGE_SIZE >> PTRLOG)
 55#endif
 56#if CONFIG_PGTABLE_LEVELS > 2
 57#define PTRS_PER_PMD	(PAGE_SIZE >> PTRLOG)
 58#endif
 59#define PTRS_PER_PTE	(PAGE_SIZE >> PTRLOG)
 60
 61#ifdef CONFIG_32BIT
 62#define USER_PTRS_PER_PGD       (TASK_SIZE / PGDIR_SIZE)
 63#else
 64#define USER_PTRS_PER_PGD       ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
 65#endif
 66
 67#ifndef __ASSEMBLER__
 68
 69#include <linux/mm_types.h>
 70#include <linux/mmzone.h>
 71#include <asm/fixmap.h>
 72#include <asm/sparsemem.h>
 73
 74struct mm_struct;
 75struct vm_area_struct;
 76
 77/*
 78 * ZERO_PAGE is a global shared page that is always zero; used
 79 * for zero-mapped memory areas etc..
 80 */
 81
 82extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
 83
 84#define ZERO_PAGE(vaddr)	virt_to_page(empty_zero_page)
 85
 86#ifdef CONFIG_32BIT
 87
 88#define VMALLOC_START	(vm_map_base + PCI_IOSIZE + (2 * PAGE_SIZE))
 89#define VMALLOC_END	(FIXADDR_START - (2 * PAGE_SIZE))
 90
 91#endif
 92
 93#ifdef CONFIG_64BIT
 94
 95#define MODULES_VADDR	(vm_map_base + PCI_IOSIZE + (2 * PAGE_SIZE))
 96#define MODULES_END	(MODULES_VADDR + SZ_256M)
 97
 98#ifdef CONFIG_KFENCE
 99#define KFENCE_AREA_SIZE	(((CONFIG_KFENCE_NUM_OBJECTS + 1) * 2 + 2) * PAGE_SIZE)
100#else
101#define KFENCE_AREA_SIZE	0
102#endif
103
104#define VMALLOC_START	MODULES_END
105
106#ifndef CONFIG_KASAN
107#define VMALLOC_END	\
108	(vm_map_base +	\
109	 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, (1UL << cpu_vabits)) - PMD_SIZE - VMEMMAP_SIZE - KFENCE_AREA_SIZE)
110#else
111#define VMALLOC_END	\
112	(vm_map_base +	\
113	 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, (1UL << cpu_vabits) / 2) - PMD_SIZE - VMEMMAP_SIZE - KFENCE_AREA_SIZE)
114#endif
115
116#define vmemmap		((struct page *)((VMALLOC_END + PMD_SIZE) & PMD_MASK))
117#define VMEMMAP_END	((unsigned long)vmemmap + VMEMMAP_SIZE - 1)
118
119#define KFENCE_AREA_START	(VMEMMAP_END + 1)
120#define KFENCE_AREA_END		(KFENCE_AREA_START + KFENCE_AREA_SIZE - 1)
121
122#endif
123
124#define ptep_get(ptep) READ_ONCE(*(ptep))
125#define pmdp_get(pmdp) READ_ONCE(*(pmdp))
126
127#define pte_ERROR(e) \
128	pr_err("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
129#ifndef __PAGETABLE_PMD_FOLDED
130#define pmd_ERROR(e) \
131	pr_err("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
132#endif
133#ifndef __PAGETABLE_PUD_FOLDED
134#define pud_ERROR(e) \
135	pr_err("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
136#endif
137#define pgd_ERROR(e) \
138	pr_err("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
139
140extern pte_t invalid_pte_table[PTRS_PER_PTE];
141
142#ifndef __PAGETABLE_PUD_FOLDED
143
144typedef struct { unsigned long pud; } pud_t;
145#define pud_val(x)	((x).pud)
146#define __pud(x)	((pud_t) { (x) })
147
148extern pud_t invalid_pud_table[PTRS_PER_PUD];
149
150/*
151 * Empty pgd/p4d entries point to the invalid_pud_table.
152 */
153static inline int p4d_none(p4d_t p4d)
154{
155	return p4d_val(p4d) == (unsigned long)invalid_pud_table;
156}
157
158static inline int p4d_bad(p4d_t p4d)
159{
160	return p4d_val(p4d) & ~PAGE_MASK;
161}
162
163static inline int p4d_present(p4d_t p4d)
164{
165	return p4d_val(p4d) != (unsigned long)invalid_pud_table;
166}
167
168static inline pud_t *p4d_pgtable(p4d_t p4d)
169{
170	return (pud_t *)p4d_val(p4d);
171}
172
173static inline void set_p4d(p4d_t *p4d, p4d_t p4dval)
174{
175	WRITE_ONCE(*p4d, p4dval);
176}
177
178static inline void p4d_clear(p4d_t *p4dp)
179{
180	set_p4d(p4dp, __p4d((unsigned long)invalid_pud_table));
181}
182
183#define p4d_phys(p4d)		PHYSADDR(p4d_val(p4d))
184#define p4d_page(p4d)		(pfn_to_page(p4d_phys(p4d) >> PAGE_SHIFT))
185
186#endif
187
188#ifndef __PAGETABLE_PMD_FOLDED
189
190typedef struct { unsigned long pmd; } pmd_t;
191#define pmd_val(x)	((x).pmd)
192#define __pmd(x)	((pmd_t) { (x) })
193
194extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
195
196/*
197 * Empty pud entries point to the invalid_pmd_table.
198 */
199static inline int pud_none(pud_t pud)
200{
201	return pud_val(pud) == (unsigned long)invalid_pmd_table;
202}
203
204static inline int pud_bad(pud_t pud)
205{
206	return pud_val(pud) & ~PAGE_MASK;
207}
208
209static inline int pud_present(pud_t pud)
210{
211	return pud_val(pud) != (unsigned long)invalid_pmd_table;
212}
213
214static inline pmd_t *pud_pgtable(pud_t pud)
215{
216	return (pmd_t *)pud_val(pud);
217}
218
219static inline void set_pud(pud_t *pud, pud_t pudval)
220{
221	WRITE_ONCE(*pud, pudval);
222}
223
224static inline void pud_clear(pud_t *pudp)
225{
226	set_pud(pudp, __pud((unsigned long)invalid_pmd_table));
227}
228
229#define pud_phys(pud)		PHYSADDR(pud_val(pud))
230#define pud_page(pud)		(pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
231
232#endif
233
234/*
235 * Empty pmd entries point to the invalid_pte_table.
236 */
237static inline int pmd_none(pmd_t pmd)
238{
239	return pmd_val(pmd) == (unsigned long)invalid_pte_table;
240}
241
242static inline int pmd_bad(pmd_t pmd)
243{
244	return (pmd_val(pmd) & ~PAGE_MASK);
245}
246
247static inline int pmd_present(pmd_t pmd)
248{
249	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
250		return !!(pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROTNONE | _PAGE_PRESENT_INVALID));
251
252	return pmd_val(pmd) != (unsigned long)invalid_pte_table;
253}
254
255static inline void set_pmd(pmd_t *pmd, pmd_t pmdval)
256{
257	WRITE_ONCE(*pmd, pmdval);
258}
259
260static inline void pmd_clear(pmd_t *pmdp)
261{
262	set_pmd(pmdp, __pmd((unsigned long)invalid_pte_table));
263}
264
265#define pmd_phys(pmd)		PHYSADDR(pmd_val(pmd))
266
267#ifndef CONFIG_TRANSPARENT_HUGEPAGE
268#define pmd_page(pmd)		(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
269#endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
270
271#define pmd_page_vaddr(pmd)	pmd_val(pmd)
272
273extern void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd);
274
275#define pte_page(x)		pfn_to_page(pte_pfn(x))
276#define pte_pfn(x)		((unsigned long)(((x).pte & _PFN_MASK) >> PFN_PTE_SHIFT))
277#define pfn_pte(pfn, prot)	__pte(((pfn) << PFN_PTE_SHIFT) | pgprot_val(prot))
278#define pfn_pmd(pfn, prot)	__pmd(((pfn) << PFN_PTE_SHIFT) | pgprot_val(prot))
279
280/*
281 * Initialize a new pgd / pud / pmd table with invalid pointers.
282 */
283extern void pgd_init(void *addr);
284extern void pud_init(void *addr);
285#define pud_init pud_init
286extern void pmd_init(void *addr);
287#define pmd_init pmd_init
288extern void kernel_pte_init(void *addr);
289#define kernel_pte_init kernel_pte_init
290
291/*
292 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
293 * are !pte_none() && !pte_present().
294 *
295 * Format of 32bit swap PTEs:
296 *
297 *   3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
298 *   1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
299 *   <------------ offset -------------> E <- type -> <-- zeroes -->
300 *
301 *   E is the exclusive marker that is not stored in swap entries.
302 *   The zero'ed bits include _PAGE_PRESENT.
303 *
304 * Format of 64bit swap PTEs:
305 *
306 *   6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3
307 *   3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2
308 *   <--------------------------- offset ---------------------------
309 *
310 *   3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
311 *   1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
312 *   --------------> E <--- type ---> <---------- zeroes ---------->
313 *
314 *   E is the exclusive marker that is not stored in swap entries.
315 *   The zero'ed bits include _PAGE_PRESENT and _PAGE_PROTNONE.
316 */
317
318#define __SWP_TYPE_BITS		(IS_ENABLED(CONFIG_32BIT) ? 5 : 7)
319#define __SWP_TYPE_MASK		((1UL << __SWP_TYPE_BITS) - 1)
320#define __SWP_TYPE_SHIFT	(IS_ENABLED(CONFIG_32BIT) ? 8 : 16)
321#define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT + 1)
322
323static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
324{
325	pte_t pte;
326	pte_val(pte) = ((type & __SWP_TYPE_MASK) << __SWP_TYPE_SHIFT) | (offset << __SWP_OFFSET_SHIFT);
327	return pte;
328}
329
330#define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
331#define __swp_offset(x)		((x).val >> __SWP_OFFSET_SHIFT)
332#define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
333
334#define __swp_entry_to_pte(x)	__pte((x).val)
335#define __swp_entry_to_pmd(x)	__pmd((x).val | _PAGE_HUGE)
336#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
337#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
338
339static inline bool pte_swp_exclusive(pte_t pte)
340{
341	return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
342}
343
344static inline pte_t pte_swp_mkexclusive(pte_t pte)
345{
346	pte_val(pte) |= _PAGE_SWP_EXCLUSIVE;
347	return pte;
348}
349
350static inline pte_t pte_swp_clear_exclusive(pte_t pte)
351{
352	pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE;
353	return pte;
354}
355
356extern void paging_init(void);
357
358#define pte_none(pte)		(!(pte_val(pte) & ~_PAGE_GLOBAL))
359#define pte_present(pte)	(pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROTNONE))
360#define pte_no_exec(pte)	(pte_val(pte) & _PAGE_NO_EXEC)
361
362static inline void set_pte(pte_t *ptep, pte_t pteval)
363{
364	WRITE_ONCE(*ptep, pteval);
365
366#ifdef CONFIG_SMP
367	if (pte_val(pteval) & _PAGE_GLOBAL)
368		DBAR(0b11000); /* o_wrw = 0b11000 */
369#endif
370}
371
372static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
373{
374	pte_t pte = ptep_get(ptep);
375	pte_val(pte) &= _PAGE_GLOBAL;
376	set_pte(ptep, pte);
377}
378
379#define PGD_T_LOG2	(__builtin_ffs(sizeof(pgd_t)) - 1)
380#define PMD_T_LOG2	(__builtin_ffs(sizeof(pmd_t)) - 1)
381#define PTE_T_LOG2	(__builtin_ffs(sizeof(pte_t)) - 1)
382
383extern pgd_t swapper_pg_dir[];
384extern pgd_t invalid_pg_dir[];
385
386/*
387 * The following only work if pte_present() is true.
388 * Undefined behaviour if not..
389 */
390static inline int pte_write(pte_t pte)	{ return pte_val(pte) & _PAGE_WRITE; }
391static inline int pte_young(pte_t pte)	{ return pte_val(pte) & _PAGE_ACCESSED; }
392static inline int pte_dirty(pte_t pte)	{ return pte_val(pte) & (_PAGE_DIRTY | _PAGE_MODIFIED); }
393
394static inline pte_t pte_mkold(pte_t pte)
395{
396	pte_val(pte) &= ~_PAGE_ACCESSED;
397	return pte;
398}
399
400static inline pte_t pte_mkyoung(pte_t pte)
401{
402	pte_val(pte) |= _PAGE_ACCESSED;
403	return pte;
404}
405
406static inline pte_t pte_mkclean(pte_t pte)
407{
408	pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_MODIFIED);
409	return pte;
410}
411
412static inline pte_t pte_mkdirty(pte_t pte)
413{
414	pte_val(pte) |= _PAGE_MODIFIED;
415	if (pte_val(pte) & _PAGE_WRITE)
416		pte_val(pte) |= _PAGE_DIRTY;
417	return pte;
418}
419
420static inline pte_t pte_mkwrite_novma(pte_t pte)
421{
422	pte_val(pte) |= _PAGE_WRITE;
423	if (pte_val(pte) & _PAGE_MODIFIED)
424		pte_val(pte) |= _PAGE_DIRTY;
425	return pte;
426}
427
428static inline pte_t pte_wrprotect(pte_t pte)
429{
430	pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_DIRTY);
431	return pte;
432}
433
434static inline int pte_huge(pte_t pte)	{ return pte_val(pte) & _PAGE_HUGE; }
435
436static inline pte_t pte_mkhuge(pte_t pte)
437{
438	pte_val(pte) |= _PAGE_HUGE;
439	return pte;
440}
441
442#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
443static inline int pte_special(pte_t pte)	{ return pte_val(pte) & _PAGE_SPECIAL; }
444static inline pte_t pte_mkspecial(pte_t pte)	{ pte_val(pte) |= _PAGE_SPECIAL; return pte; }
445#endif /* CONFIG_ARCH_HAS_PTE_SPECIAL */
446
447#define pte_accessible pte_accessible
448static inline unsigned long pte_accessible(struct mm_struct *mm, pte_t a)
449{
450	if (pte_val(a) & _PAGE_PRESENT)
451		return true;
452
453	if ((pte_val(a) & _PAGE_PROTNONE) &&
454			atomic_read(&mm->tlb_flush_pending))
455		return true;
456
457	return false;
458}
459
460static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
461{
462	if (pte_val(pte) & _PAGE_DIRTY)
463		pte_val(pte) |= _PAGE_MODIFIED;
464
465	return __pte((pte_val(pte) & _PAGE_CHG_MASK) |
466		     (pgprot_val(newprot) & ~_PAGE_CHG_MASK));
467}
468
469extern void __update_tlb(struct vm_area_struct *vma,
470			unsigned long address, pte_t *ptep);
471
472static inline void update_mmu_cache_range(struct vm_fault *vmf,
473		struct vm_area_struct *vma, unsigned long address,
474		pte_t *ptep, unsigned int nr)
475{
476	for (;;) {
477		__update_tlb(vma, address, ptep);
478		if (--nr == 0)
479			break;
480		address += PAGE_SIZE;
481		ptep++;
482	}
483}
484#define update_mmu_cache(vma, addr, ptep) \
485	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
486
487#define update_mmu_tlb_range(vma, addr, ptep, nr) \
488	update_mmu_cache_range(NULL, vma, addr, ptep, nr)
489
490static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
491			unsigned long address, pmd_t *pmdp)
492{
493	__update_tlb(vma, address, (pte_t *)pmdp);
494}
495
496static inline unsigned long pmd_pfn(pmd_t pmd)
497{
498	return (pmd_val(pmd) & _PFN_MASK) >> PFN_PTE_SHIFT;
499}
500
501#ifdef CONFIG_TRANSPARENT_HUGEPAGE
502
503/* We don't have hardware dirty/accessed bits, generic_pmdp_establish is fine.*/
504#define pmdp_establish generic_pmdp_establish
505
506static inline int pmd_trans_huge(pmd_t pmd)
507{
508	return !!(pmd_val(pmd) & _PAGE_HUGE) && pmd_present(pmd);
509}
510
511static inline pmd_t pmd_mkhuge(pmd_t pmd)
512{
513	pmd_val(pmd) = (pmd_val(pmd) & ~(_PAGE_GLOBAL)) |
514		((pmd_val(pmd) & _PAGE_GLOBAL) << (_PAGE_HGLOBAL_SHIFT - _PAGE_GLOBAL_SHIFT));
515	pmd_val(pmd) |= _PAGE_HUGE;
516
517	return pmd;
518}
519
520#define pmd_write pmd_write
521static inline int pmd_write(pmd_t pmd)
522{
523	return !!(pmd_val(pmd) & _PAGE_WRITE);
524}
525
526static inline pmd_t pmd_mkwrite_novma(pmd_t pmd)
527{
528	pmd_val(pmd) |= _PAGE_WRITE;
529	if (pmd_val(pmd) & _PAGE_MODIFIED)
530		pmd_val(pmd) |= _PAGE_DIRTY;
531	return pmd;
532}
533
534static inline pmd_t pmd_wrprotect(pmd_t pmd)
535{
536	pmd_val(pmd) &= ~(_PAGE_WRITE | _PAGE_DIRTY);
537	return pmd;
538}
539
540#define pmd_dirty pmd_dirty
541static inline int pmd_dirty(pmd_t pmd)
542{
543	return !!(pmd_val(pmd) & (_PAGE_DIRTY | _PAGE_MODIFIED));
544}
545
546static inline pmd_t pmd_mkclean(pmd_t pmd)
547{
548	pmd_val(pmd) &= ~(_PAGE_DIRTY | _PAGE_MODIFIED);
549	return pmd;
550}
551
552static inline pmd_t pmd_mkdirty(pmd_t pmd)
553{
554	pmd_val(pmd) |= _PAGE_MODIFIED;
555	if (pmd_val(pmd) & _PAGE_WRITE)
556		pmd_val(pmd) |= _PAGE_DIRTY;
557	return pmd;
558}
559
560#define pmd_young pmd_young
561static inline int pmd_young(pmd_t pmd)
562{
563	return !!(pmd_val(pmd) & _PAGE_ACCESSED);
564}
565
566static inline pmd_t pmd_mkold(pmd_t pmd)
567{
568	pmd_val(pmd) &= ~_PAGE_ACCESSED;
569	return pmd;
570}
571
572static inline pmd_t pmd_mkyoung(pmd_t pmd)
573{
574	pmd_val(pmd) |= _PAGE_ACCESSED;
575	return pmd;
576}
577
578static inline struct page *pmd_page(pmd_t pmd)
579{
580	if (pmd_trans_huge(pmd))
581		return pfn_to_page(pmd_pfn(pmd));
582
583	return pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT);
584}
585
586static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
587{
588	if (pmd_val(pmd) & _PAGE_DIRTY)
589		pmd_val(pmd) |= _PAGE_MODIFIED;
590
591	return __pmd((pmd_val(pmd) & _HPAGE_CHG_MASK) |
592		     (pgprot_val(newprot) & ~_HPAGE_CHG_MASK));
593}
594
595static inline pmd_t pmd_mkinvalid(pmd_t pmd)
596{
597	pmd_val(pmd) |= _PAGE_PRESENT_INVALID;
598	pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY | _PAGE_PROTNONE);
599
600	return pmd;
601}
602
603/*
604 * The generic version pmdp_huge_get_and_clear uses a version of pmd_clear() with a
605 * different prototype.
606 */
607#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
608static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
609					    unsigned long address, pmd_t *pmdp)
610{
611	pmd_t old = pmdp_get(pmdp);
612
613	pmd_clear(pmdp);
614
615	return old;
616}
617
618#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
619
620#ifdef CONFIG_NUMA_BALANCING
621static inline long pte_protnone(pte_t pte)
622{
623	return (pte_val(pte) & _PAGE_PROTNONE);
624}
625
626static inline long pmd_protnone(pmd_t pmd)
627{
628	return (pmd_val(pmd) & _PAGE_PROTNONE);
629}
630#endif /* CONFIG_NUMA_BALANCING */
631
632#define pmd_leaf(pmd)		((pmd_val(pmd) & _PAGE_HUGE) != 0)
633#define pud_leaf(pud)		((pud_val(pud) & _PAGE_HUGE) != 0)
634
635/*
636 * We provide our own get_unmapped area to cope with the virtual aliasing
637 * constraints placed on us by the cache architecture.
638 */
639#define HAVE_ARCH_UNMAPPED_AREA
640#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
641
642#endif /* !__ASSEMBLER__ */
643
644#endif /* _ASM_PGTABLE_H */