xref: /openbmc/linux/arch/mips/include/asm/pgtable.h (revision a8da474e)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2003 Ralf Baechle
7  */
8 #ifndef _ASM_PGTABLE_H
9 #define _ASM_PGTABLE_H
10 
11 #include <linux/mm_types.h>
12 #include <linux/mmzone.h>
13 #ifdef CONFIG_32BIT
14 #include <asm/pgtable-32.h>
15 #endif
16 #ifdef CONFIG_64BIT
17 #include <asm/pgtable-64.h>
18 #endif
19 
20 #include <asm/io.h>
21 #include <asm/pgtable-bits.h>
22 
23 struct mm_struct;
24 struct vm_area_struct;
25 
26 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _CACHE_CACHABLE_NONCOHERENT)
27 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | \
28 				 _page_cachable_default)
29 #define PAGE_COPY	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_NO_EXEC | \
30 				 _page_cachable_default)
31 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_READ | \
32 				 _page_cachable_default)
33 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
34 				 _PAGE_GLOBAL | _page_cachable_default)
35 #define PAGE_KERNEL_NC	__pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
36 				 _PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT)
37 #define PAGE_USERIO	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
38 				 _page_cachable_default)
39 #define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
40 			__WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
41 
42 /*
43  * If _PAGE_NO_EXEC is not defined, we can't do page protection for
44  * execute, and consider it to be the same as read. Also, write
45  * permissions imply read permissions. This is the closest we can get
46  * by reasonable means..
47  */
48 
49 /*
50  * Dummy values to fill the table in mmap.c
51  * The real values will be generated at runtime
52  */
53 #define __P000 __pgprot(0)
54 #define __P001 __pgprot(0)
55 #define __P010 __pgprot(0)
56 #define __P011 __pgprot(0)
57 #define __P100 __pgprot(0)
58 #define __P101 __pgprot(0)
59 #define __P110 __pgprot(0)
60 #define __P111 __pgprot(0)
61 
62 #define __S000 __pgprot(0)
63 #define __S001 __pgprot(0)
64 #define __S010 __pgprot(0)
65 #define __S011 __pgprot(0)
66 #define __S100 __pgprot(0)
67 #define __S101 __pgprot(0)
68 #define __S110 __pgprot(0)
69 #define __S111 __pgprot(0)
70 
71 extern unsigned long _page_cachable_default;
72 
73 /*
74  * ZERO_PAGE is a global shared page that is always zero; used
75  * for zero-mapped memory areas etc..
76  */
77 
78 extern unsigned long empty_zero_page;
79 extern unsigned long zero_page_mask;
80 
81 #define ZERO_PAGE(vaddr) \
82 	(virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
83 #define __HAVE_COLOR_ZERO_PAGE
84 
85 extern void paging_init(void);
86 
87 /*
88  * Conversion functions: convert a page and protection to a page entry,
89  * and a page entry and page directory to the page they refer to.
90  */
91 #define pmd_phys(pmd)		virt_to_phys((void *)pmd_val(pmd))
92 
93 #define __pmd_page(pmd)		(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
94 #ifndef CONFIG_TRANSPARENT_HUGEPAGE
95 #define pmd_page(pmd)		__pmd_page(pmd)
96 #endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
97 
98 #define pmd_page_vaddr(pmd)	pmd_val(pmd)
99 
100 #define htw_stop()							\
101 do {									\
102 	unsigned long flags;						\
103 									\
104 	if (cpu_has_htw) {						\
105 		local_irq_save(flags);					\
106 		if(!raw_current_cpu_data.htw_seq++) {			\
107 			write_c0_pwctl(read_c0_pwctl() &		\
108 				       ~(1 << MIPS_PWCTL_PWEN_SHIFT));	\
109 			back_to_back_c0_hazard();			\
110 		}							\
111 		local_irq_restore(flags);				\
112 	}								\
113 } while(0)
114 
115 #define htw_start()							\
116 do {									\
117 	unsigned long flags;						\
118 									\
119 	if (cpu_has_htw) {						\
120 		local_irq_save(flags);					\
121 		if (!--raw_current_cpu_data.htw_seq) {			\
122 			write_c0_pwctl(read_c0_pwctl() |		\
123 				       (1 << MIPS_PWCTL_PWEN_SHIFT));	\
124 			back_to_back_c0_hazard();			\
125 		}							\
126 		local_irq_restore(flags);				\
127 	}								\
128 } while(0)
129 
130 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
131 
132 #define pte_none(pte)		(!(((pte).pte_high) & ~_PAGE_GLOBAL))
133 #define pte_present(pte)	((pte).pte_low & _PAGE_PRESENT)
134 
135 static inline void set_pte(pte_t *ptep, pte_t pte)
136 {
137 	ptep->pte_high = pte.pte_high;
138 	smp_wmb();
139 	ptep->pte_low = pte.pte_low;
140 
141 	if (pte.pte_high & _PAGE_GLOBAL) {
142 		pte_t *buddy = ptep_buddy(ptep);
143 		/*
144 		 * Make sure the buddy is global too (if it's !none,
145 		 * it better already be global)
146 		 */
147 		if (pte_none(*buddy))
148 			buddy->pte_high |= _PAGE_GLOBAL;
149 	}
150 }
151 #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
152 
153 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
154 {
155 	pte_t null = __pte(0);
156 
157 	htw_stop();
158 	/* Preserve global status for the pair */
159 	if (ptep_buddy(ptep)->pte_high & _PAGE_GLOBAL)
160 		null.pte_high = _PAGE_GLOBAL;
161 
162 	set_pte_at(mm, addr, ptep, null);
163 	htw_start();
164 }
165 #else
166 
167 #define pte_none(pte)		(!(pte_val(pte) & ~_PAGE_GLOBAL))
168 #define pte_present(pte)	(pte_val(pte) & _PAGE_PRESENT)
169 
170 /*
171  * Certain architectures need to do special things when pte's
172  * within a page table are directly modified.  Thus, the following
173  * hook is made available.
174  */
175 static inline void set_pte(pte_t *ptep, pte_t pteval)
176 {
177 	*ptep = pteval;
178 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
179 	if (pte_val(pteval) & _PAGE_GLOBAL) {
180 		pte_t *buddy = ptep_buddy(ptep);
181 		/*
182 		 * Make sure the buddy is global too (if it's !none,
183 		 * it better already be global)
184 		 */
185 #ifdef CONFIG_SMP
186 		/*
187 		 * For SMP, multiple CPUs can race, so we need to do
188 		 * this atomically.
189 		 */
190 #ifdef CONFIG_64BIT
191 #define LL_INSN "lld"
192 #define SC_INSN "scd"
193 #else /* CONFIG_32BIT */
194 #define LL_INSN "ll"
195 #define SC_INSN "sc"
196 #endif
197 		unsigned long page_global = _PAGE_GLOBAL;
198 		unsigned long tmp;
199 
200 		__asm__ __volatile__ (
201 			"	.set	push\n"
202 			"	.set	noreorder\n"
203 			"1:	" LL_INSN "	%[tmp], %[buddy]\n"
204 			"	bnez	%[tmp], 2f\n"
205 			"	 or	%[tmp], %[tmp], %[global]\n"
206 			"	" SC_INSN "	%[tmp], %[buddy]\n"
207 			"	beqz	%[tmp], 1b\n"
208 			"	 nop\n"
209 			"2:\n"
210 			"	.set pop"
211 			: [buddy] "+m" (buddy->pte),
212 			  [tmp] "=&r" (tmp)
213 			: [global] "r" (page_global));
214 #else /* !CONFIG_SMP */
215 		if (pte_none(*buddy))
216 			pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL;
217 #endif /* CONFIG_SMP */
218 	}
219 #endif
220 }
221 #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
222 
223 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
224 {
225 	htw_stop();
226 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
227 	/* Preserve global status for the pair */
228 	if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
229 		set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
230 	else
231 #endif
232 		set_pte_at(mm, addr, ptep, __pte(0));
233 	htw_start();
234 }
235 #endif
236 
237 /*
238  * (pmds are folded into puds so this doesn't get actually called,
239  * but the define is needed for a generic inline function.)
240  */
241 #define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)
242 
243 #ifndef __PAGETABLE_PMD_FOLDED
244 /*
245  * (puds are folded into pgds so this doesn't get actually called,
246  * but the define is needed for a generic inline function.)
247  */
248 #define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while(0)
249 #endif
250 
251 #define PGD_T_LOG2	(__builtin_ffs(sizeof(pgd_t)) - 1)
252 #define PMD_T_LOG2	(__builtin_ffs(sizeof(pmd_t)) - 1)
253 #define PTE_T_LOG2	(__builtin_ffs(sizeof(pte_t)) - 1)
254 
255 /*
256  * We used to declare this array with size but gcc 3.3 and older are not able
257  * to find that this expression is a constant, so the size is dropped.
258  */
259 extern pgd_t swapper_pg_dir[];
260 
261 /*
262  * The following only work if pte_present() is true.
263  * Undefined behaviour if not..
264  */
265 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
266 static inline int pte_write(pte_t pte)	{ return pte.pte_low & _PAGE_WRITE; }
267 static inline int pte_dirty(pte_t pte)	{ return pte.pte_low & _PAGE_MODIFIED; }
268 static inline int pte_young(pte_t pte)	{ return pte.pte_low & _PAGE_ACCESSED; }
269 
270 static inline pte_t pte_wrprotect(pte_t pte)
271 {
272 	pte.pte_low  &= ~_PAGE_WRITE;
273 	pte.pte_high &= ~_PAGE_SILENT_WRITE;
274 	return pte;
275 }
276 
277 static inline pte_t pte_mkclean(pte_t pte)
278 {
279 	pte.pte_low  &= ~_PAGE_MODIFIED;
280 	pte.pte_high &= ~_PAGE_SILENT_WRITE;
281 	return pte;
282 }
283 
284 static inline pte_t pte_mkold(pte_t pte)
285 {
286 	pte.pte_low  &= ~_PAGE_ACCESSED;
287 	pte.pte_high &= ~_PAGE_SILENT_READ;
288 	return pte;
289 }
290 
291 static inline pte_t pte_mkwrite(pte_t pte)
292 {
293 	pte.pte_low |= _PAGE_WRITE;
294 	if (pte.pte_low & _PAGE_MODIFIED)
295 		pte.pte_high |= _PAGE_SILENT_WRITE;
296 	return pte;
297 }
298 
299 static inline pte_t pte_mkdirty(pte_t pte)
300 {
301 	pte.pte_low |= _PAGE_MODIFIED;
302 	if (pte.pte_low & _PAGE_WRITE)
303 		pte.pte_high |= _PAGE_SILENT_WRITE;
304 	return pte;
305 }
306 
307 static inline pte_t pte_mkyoung(pte_t pte)
308 {
309 	pte.pte_low |= _PAGE_ACCESSED;
310 	if (pte.pte_low & _PAGE_READ)
311 		pte.pte_high |= _PAGE_SILENT_READ;
312 	return pte;
313 }
314 #else
315 static inline int pte_write(pte_t pte)	{ return pte_val(pte) & _PAGE_WRITE; }
316 static inline int pte_dirty(pte_t pte)	{ return pte_val(pte) & _PAGE_MODIFIED; }
317 static inline int pte_young(pte_t pte)	{ return pte_val(pte) & _PAGE_ACCESSED; }
318 
319 static inline pte_t pte_wrprotect(pte_t pte)
320 {
321 	pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
322 	return pte;
323 }
324 
325 static inline pte_t pte_mkclean(pte_t pte)
326 {
327 	pte_val(pte) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
328 	return pte;
329 }
330 
331 static inline pte_t pte_mkold(pte_t pte)
332 {
333 	pte_val(pte) &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ);
334 	return pte;
335 }
336 
337 static inline pte_t pte_mkwrite(pte_t pte)
338 {
339 	pte_val(pte) |= _PAGE_WRITE;
340 	if (pte_val(pte) & _PAGE_MODIFIED)
341 		pte_val(pte) |= _PAGE_SILENT_WRITE;
342 	return pte;
343 }
344 
345 static inline pte_t pte_mkdirty(pte_t pte)
346 {
347 	pte_val(pte) |= _PAGE_MODIFIED;
348 	if (pte_val(pte) & _PAGE_WRITE)
349 		pte_val(pte) |= _PAGE_SILENT_WRITE;
350 	return pte;
351 }
352 
353 static inline pte_t pte_mkyoung(pte_t pte)
354 {
355 	pte_val(pte) |= _PAGE_ACCESSED;
356 #ifdef CONFIG_CPU_MIPSR2
357 	if (!(pte_val(pte) & _PAGE_NO_READ))
358 		pte_val(pte) |= _PAGE_SILENT_READ;
359 	else
360 #endif
361 	if (pte_val(pte) & _PAGE_READ)
362 		pte_val(pte) |= _PAGE_SILENT_READ;
363 	return pte;
364 }
365 
366 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
367 static inline int pte_huge(pte_t pte)	{ return pte_val(pte) & _PAGE_HUGE; }
368 
369 static inline pte_t pte_mkhuge(pte_t pte)
370 {
371 	pte_val(pte) |= _PAGE_HUGE;
372 	return pte;
373 }
374 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
375 #endif
376 static inline int pte_special(pte_t pte)	{ return 0; }
377 static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }
378 
379 /*
380  * Macro to make mark a page protection value as "uncacheable".	 Note
381  * that "protection" is really a misnomer here as the protection value
382  * contains the memory attribute bits, dirty bits, and various other
383  * bits as well.
384  */
385 #define pgprot_noncached pgprot_noncached
386 
387 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
388 {
389 	unsigned long prot = pgprot_val(_prot);
390 
391 	prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
392 
393 	return __pgprot(prot);
394 }
395 
396 #define pgprot_writecombine pgprot_writecombine
397 
398 static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
399 {
400 	unsigned long prot = pgprot_val(_prot);
401 
402 	/* cpu_data[0].writecombine is already shifted by _CACHE_SHIFT */
403 	prot = (prot & ~_CACHE_MASK) | cpu_data[0].writecombine;
404 
405 	return __pgprot(prot);
406 }
407 
408 /*
409  * Conversion functions: convert a page and protection to a page entry,
410  * and a page entry and page directory to the page they refer to.
411  */
412 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
413 
414 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
415 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
416 {
417 	pte.pte_low  &= (_PAGE_MODIFIED | _PAGE_ACCESSED | _PFNX_MASK);
418 	pte.pte_high &= (_PFN_MASK | _CACHE_MASK);
419 	pte.pte_low  |= pgprot_val(newprot) & ~_PFNX_MASK;
420 	pte.pte_high |= pgprot_val(newprot) & ~_PFN_MASK;
421 	return pte;
422 }
423 #else
424 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
425 {
426 	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
427 }
428 #endif
429 
430 
431 extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
432 	pte_t pte);
433 extern void __update_cache(struct vm_area_struct *vma, unsigned long address,
434 	pte_t pte);
435 
436 static inline void update_mmu_cache(struct vm_area_struct *vma,
437 	unsigned long address, pte_t *ptep)
438 {
439 	pte_t pte = *ptep;
440 	__update_tlb(vma, address, pte);
441 	__update_cache(vma, address, pte);
442 }
443 
444 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
445 	unsigned long address, pmd_t *pmdp)
446 {
447 	pte_t pte = *(pte_t *)pmdp;
448 
449 	__update_tlb(vma, address, pte);
450 }
451 
452 #define kern_addr_valid(addr)	(1)
453 
454 #ifdef CONFIG_PHYS_ADDR_T_64BIT
455 extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot);
456 
457 static inline int io_remap_pfn_range(struct vm_area_struct *vma,
458 		unsigned long vaddr,
459 		unsigned long pfn,
460 		unsigned long size,
461 		pgprot_t prot)
462 {
463 	phys_addr_t phys_addr_high = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
464 	return remap_pfn_range(vma, vaddr, phys_addr_high >> PAGE_SHIFT, size, prot);
465 }
466 #define io_remap_pfn_range io_remap_pfn_range
467 #endif
468 
469 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
470 
471 extern int has_transparent_hugepage(void);
472 
473 static inline int pmd_trans_huge(pmd_t pmd)
474 {
475 	return !!(pmd_val(pmd) & _PAGE_HUGE);
476 }
477 
478 static inline pmd_t pmd_mkhuge(pmd_t pmd)
479 {
480 	pmd_val(pmd) |= _PAGE_HUGE;
481 
482 	return pmd;
483 }
484 
485 static inline int pmd_trans_splitting(pmd_t pmd)
486 {
487 	return !!(pmd_val(pmd) & _PAGE_SPLITTING);
488 }
489 
490 static inline pmd_t pmd_mksplitting(pmd_t pmd)
491 {
492 	pmd_val(pmd) |= _PAGE_SPLITTING;
493 
494 	return pmd;
495 }
496 
497 extern void set_pmd_at(struct mm_struct *mm, unsigned long addr,
498 		       pmd_t *pmdp, pmd_t pmd);
499 
500 #define __HAVE_ARCH_PMDP_SPLITTING_FLUSH
501 /* Extern to avoid header file madness */
502 extern void pmdp_splitting_flush(struct vm_area_struct *vma,
503 					unsigned long address,
504 					pmd_t *pmdp);
505 
506 #define __HAVE_ARCH_PMD_WRITE
507 static inline int pmd_write(pmd_t pmd)
508 {
509 	return !!(pmd_val(pmd) & _PAGE_WRITE);
510 }
511 
512 static inline pmd_t pmd_wrprotect(pmd_t pmd)
513 {
514 	pmd_val(pmd) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
515 	return pmd;
516 }
517 
518 static inline pmd_t pmd_mkwrite(pmd_t pmd)
519 {
520 	pmd_val(pmd) |= _PAGE_WRITE;
521 	if (pmd_val(pmd) & _PAGE_MODIFIED)
522 		pmd_val(pmd) |= _PAGE_SILENT_WRITE;
523 
524 	return pmd;
525 }
526 
527 static inline int pmd_dirty(pmd_t pmd)
528 {
529 	return !!(pmd_val(pmd) & _PAGE_MODIFIED);
530 }
531 
532 static inline pmd_t pmd_mkclean(pmd_t pmd)
533 {
534 	pmd_val(pmd) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
535 	return pmd;
536 }
537 
538 static inline pmd_t pmd_mkdirty(pmd_t pmd)
539 {
540 	pmd_val(pmd) |= _PAGE_MODIFIED;
541 	if (pmd_val(pmd) & _PAGE_WRITE)
542 		pmd_val(pmd) |= _PAGE_SILENT_WRITE;
543 
544 	return pmd;
545 }
546 
547 static inline int pmd_young(pmd_t pmd)
548 {
549 	return !!(pmd_val(pmd) & _PAGE_ACCESSED);
550 }
551 
552 static inline pmd_t pmd_mkold(pmd_t pmd)
553 {
554 	pmd_val(pmd) &= ~(_PAGE_ACCESSED|_PAGE_SILENT_READ);
555 
556 	return pmd;
557 }
558 
559 static inline pmd_t pmd_mkyoung(pmd_t pmd)
560 {
561 	pmd_val(pmd) |= _PAGE_ACCESSED;
562 
563 #ifdef CONFIG_CPU_MIPSR2
564 	if (!(pmd_val(pmd) & _PAGE_NO_READ))
565 		pmd_val(pmd) |= _PAGE_SILENT_READ;
566 	else
567 #endif
568 	if (pmd_val(pmd) & _PAGE_READ)
569 		pmd_val(pmd) |= _PAGE_SILENT_READ;
570 
571 	return pmd;
572 }
573 
574 /* Extern to avoid header file madness */
575 extern pmd_t mk_pmd(struct page *page, pgprot_t prot);
576 
577 static inline unsigned long pmd_pfn(pmd_t pmd)
578 {
579 	return pmd_val(pmd) >> _PFN_SHIFT;
580 }
581 
582 static inline struct page *pmd_page(pmd_t pmd)
583 {
584 	if (pmd_trans_huge(pmd))
585 		return pfn_to_page(pmd_pfn(pmd));
586 
587 	return pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT);
588 }
589 
590 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
591 {
592 	pmd_val(pmd) = (pmd_val(pmd) & _PAGE_CHG_MASK) | pgprot_val(newprot);
593 	return pmd;
594 }
595 
596 static inline pmd_t pmd_mknotpresent(pmd_t pmd)
597 {
598 	pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY);
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
608 static 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;
612 
613 	pmd_clear(pmdp);
614 
615 	return old;
616 }
617 
618 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
619 
620 #include <asm-generic/pgtable.h>
621 
622 /*
623  * uncached accelerated TLB map for video memory access
624  */
625 #ifdef CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED
626 #define __HAVE_PHYS_MEM_ACCESS_PROT
627 
628 struct file;
629 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
630 		unsigned long size, pgprot_t vma_prot);
631 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
632 		unsigned long size, pgprot_t *vma_prot);
633 #endif
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 /*
643  * No page table caches to initialise
644  */
645 #define pgtable_cache_init()	do { } while (0)
646 
647 #endif /* _ASM_PGTABLE_H */
648