xref: /openbmc/linux/arch/arm64/include/asm/pgtable.h (revision 2209fda3)
1 /*
2  * Copyright (C) 2012 ARM Ltd.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
15  */
16 #ifndef __ASM_PGTABLE_H
17 #define __ASM_PGTABLE_H
18 
19 #include <asm/bug.h>
20 #include <asm/proc-fns.h>
21 
22 #include <asm/memory.h>
23 #include <asm/pgtable-hwdef.h>
24 #include <asm/pgtable-prot.h>
25 
26 /*
27  * VMALLOC range.
28  *
29  * VMALLOC_START: beginning of the kernel vmalloc space
30  * VMALLOC_END: extends to the available space below vmmemmap, PCI I/O space
31  *	and fixed mappings
32  */
33 #define VMALLOC_START		(MODULES_END)
34 #define VMALLOC_END		(PAGE_OFFSET - PUD_SIZE - VMEMMAP_SIZE - SZ_64K)
35 
36 #define vmemmap			((struct page *)VMEMMAP_START - (memstart_addr >> PAGE_SHIFT))
37 
38 #define FIRST_USER_ADDRESS	0UL
39 
40 #ifndef __ASSEMBLY__
41 
42 #include <asm/cmpxchg.h>
43 #include <asm/fixmap.h>
44 #include <linux/mmdebug.h>
45 #include <linux/mm_types.h>
46 #include <linux/sched.h>
47 
48 extern void __pte_error(const char *file, int line, unsigned long val);
49 extern void __pmd_error(const char *file, int line, unsigned long val);
50 extern void __pud_error(const char *file, int line, unsigned long val);
51 extern void __pgd_error(const char *file, int line, unsigned long val);
52 
53 /*
54  * ZERO_PAGE is a global shared page that is always zero: used
55  * for zero-mapped memory areas etc..
56  */
57 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
58 #define ZERO_PAGE(vaddr)	phys_to_page(__pa_symbol(empty_zero_page))
59 
60 #define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte_val(pte))
61 
62 /*
63  * Macros to convert between a physical address and its placement in a
64  * page table entry, taking care of 52-bit addresses.
65  */
66 #ifdef CONFIG_ARM64_PA_BITS_52
67 #define __pte_to_phys(pte)	\
68 	((pte_val(pte) & PTE_ADDR_LOW) | ((pte_val(pte) & PTE_ADDR_HIGH) << 36))
69 #define __phys_to_pte_val(phys)	(((phys) | ((phys) >> 36)) & PTE_ADDR_MASK)
70 #else
71 #define __pte_to_phys(pte)	(pte_val(pte) & PTE_ADDR_MASK)
72 #define __phys_to_pte_val(phys)	(phys)
73 #endif
74 
75 #define pte_pfn(pte)		(__pte_to_phys(pte) >> PAGE_SHIFT)
76 #define pfn_pte(pfn,prot)	\
77 	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
78 
79 #define pte_none(pte)		(!pte_val(pte))
80 #define pte_clear(mm,addr,ptep)	set_pte(ptep, __pte(0))
81 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
82 
83 /*
84  * The following only work if pte_present(). Undefined behaviour otherwise.
85  */
86 #define pte_present(pte)	(!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
87 #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
88 #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
89 #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
90 #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
91 #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
92 
93 #define pte_cont_addr_end(addr, end)						\
94 ({	unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK;	\
95 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
96 })
97 
98 #define pmd_cont_addr_end(addr, end)						\
99 ({	unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK;	\
100 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
101 })
102 
103 #define pte_hw_dirty(pte)	(pte_write(pte) && !(pte_val(pte) & PTE_RDONLY))
104 #define pte_sw_dirty(pte)	(!!(pte_val(pte) & PTE_DIRTY))
105 #define pte_dirty(pte)		(pte_sw_dirty(pte) || pte_hw_dirty(pte))
106 
107 #define pte_valid(pte)		(!!(pte_val(pte) & PTE_VALID))
108 /*
109  * Execute-only user mappings do not have the PTE_USER bit set. All valid
110  * kernel mappings have the PTE_UXN bit set.
111  */
112 #define pte_valid_not_user(pte) \
113 	((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
114 #define pte_valid_young(pte) \
115 	((pte_val(pte) & (PTE_VALID | PTE_AF)) == (PTE_VALID | PTE_AF))
116 #define pte_valid_user(pte) \
117 	((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER))
118 
119 /*
120  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
121  * so that we don't erroneously return false for pages that have been
122  * remapped as PROT_NONE but are yet to be flushed from the TLB.
123  */
124 #define pte_accessible(mm, pte)	\
125 	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid_young(pte))
126 
127 /*
128  * p??_access_permitted() is true for valid user mappings (subject to the
129  * write permission check) other than user execute-only which do not have the
130  * PTE_USER bit set. PROT_NONE mappings do not have the PTE_VALID bit set.
131  */
132 #define pte_access_permitted(pte, write) \
133 	(pte_valid_user(pte) && (!(write) || pte_write(pte)))
134 #define pmd_access_permitted(pmd, write) \
135 	(pte_access_permitted(pmd_pte(pmd), (write)))
136 #define pud_access_permitted(pud, write) \
137 	(pte_access_permitted(pud_pte(pud), (write)))
138 
139 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
140 {
141 	pte_val(pte) &= ~pgprot_val(prot);
142 	return pte;
143 }
144 
145 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
146 {
147 	pte_val(pte) |= pgprot_val(prot);
148 	return pte;
149 }
150 
151 static inline pte_t pte_wrprotect(pte_t pte)
152 {
153 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
154 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
155 	return pte;
156 }
157 
158 static inline pte_t pte_mkwrite(pte_t pte)
159 {
160 	pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
161 	pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
162 	return pte;
163 }
164 
165 static inline pte_t pte_mkclean(pte_t pte)
166 {
167 	pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
168 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
169 
170 	return pte;
171 }
172 
173 static inline pte_t pte_mkdirty(pte_t pte)
174 {
175 	pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
176 
177 	if (pte_write(pte))
178 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
179 
180 	return pte;
181 }
182 
183 static inline pte_t pte_mkold(pte_t pte)
184 {
185 	return clear_pte_bit(pte, __pgprot(PTE_AF));
186 }
187 
188 static inline pte_t pte_mkyoung(pte_t pte)
189 {
190 	return set_pte_bit(pte, __pgprot(PTE_AF));
191 }
192 
193 static inline pte_t pte_mkspecial(pte_t pte)
194 {
195 	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
196 }
197 
198 static inline pte_t pte_mkcont(pte_t pte)
199 {
200 	pte = set_pte_bit(pte, __pgprot(PTE_CONT));
201 	return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
202 }
203 
204 static inline pte_t pte_mknoncont(pte_t pte)
205 {
206 	return clear_pte_bit(pte, __pgprot(PTE_CONT));
207 }
208 
209 static inline pte_t pte_mkpresent(pte_t pte)
210 {
211 	return set_pte_bit(pte, __pgprot(PTE_VALID));
212 }
213 
214 static inline pmd_t pmd_mkcont(pmd_t pmd)
215 {
216 	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
217 }
218 
219 static inline void set_pte(pte_t *ptep, pte_t pte)
220 {
221 	WRITE_ONCE(*ptep, pte);
222 
223 	/*
224 	 * Only if the new pte is valid and kernel, otherwise TLB maintenance
225 	 * or update_mmu_cache() have the necessary barriers.
226 	 */
227 	if (pte_valid_not_user(pte))
228 		dsb(ishst);
229 }
230 
231 extern void __sync_icache_dcache(pte_t pteval);
232 
233 /*
234  * PTE bits configuration in the presence of hardware Dirty Bit Management
235  * (PTE_WRITE == PTE_DBM):
236  *
237  * Dirty  Writable | PTE_RDONLY  PTE_WRITE  PTE_DIRTY (sw)
238  *   0      0      |   1           0          0
239  *   0      1      |   1           1          0
240  *   1      0      |   1           0          1
241  *   1      1      |   0           1          x
242  *
243  * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
244  * the page fault mechanism. Checking the dirty status of a pte becomes:
245  *
246  *   PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
247  */
248 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
249 			      pte_t *ptep, pte_t pte)
250 {
251 	pte_t old_pte;
252 
253 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
254 		__sync_icache_dcache(pte);
255 
256 	/*
257 	 * If the existing pte is valid, check for potential race with
258 	 * hardware updates of the pte (ptep_set_access_flags safely changes
259 	 * valid ptes without going through an invalid entry).
260 	 */
261 	old_pte = READ_ONCE(*ptep);
262 	if (IS_ENABLED(CONFIG_DEBUG_VM) && pte_valid(old_pte) && pte_valid(pte) &&
263 	   (mm == current->active_mm || atomic_read(&mm->mm_users) > 1)) {
264 		VM_WARN_ONCE(!pte_young(pte),
265 			     "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
266 			     __func__, pte_val(old_pte), pte_val(pte));
267 		VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
268 			     "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
269 			     __func__, pte_val(old_pte), pte_val(pte));
270 	}
271 
272 	set_pte(ptep, pte);
273 }
274 
275 #define __HAVE_ARCH_PTE_SAME
276 static inline int pte_same(pte_t pte_a, pte_t pte_b)
277 {
278 	pteval_t lhs, rhs;
279 
280 	lhs = pte_val(pte_a);
281 	rhs = pte_val(pte_b);
282 
283 	if (pte_present(pte_a))
284 		lhs &= ~PTE_RDONLY;
285 
286 	if (pte_present(pte_b))
287 		rhs &= ~PTE_RDONLY;
288 
289 	return (lhs == rhs);
290 }
291 
292 /*
293  * Huge pte definitions.
294  */
295 #define pte_huge(pte)		(!(pte_val(pte) & PTE_TABLE_BIT))
296 #define pte_mkhuge(pte)		(__pte(pte_val(pte) & ~PTE_TABLE_BIT))
297 
298 /*
299  * Hugetlb definitions.
300  */
301 #define HUGE_MAX_HSTATE		4
302 #define HPAGE_SHIFT		PMD_SHIFT
303 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
304 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
305 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
306 
307 static inline pte_t pgd_pte(pgd_t pgd)
308 {
309 	return __pte(pgd_val(pgd));
310 }
311 
312 static inline pte_t pud_pte(pud_t pud)
313 {
314 	return __pte(pud_val(pud));
315 }
316 
317 static inline pmd_t pud_pmd(pud_t pud)
318 {
319 	return __pmd(pud_val(pud));
320 }
321 
322 static inline pte_t pmd_pte(pmd_t pmd)
323 {
324 	return __pte(pmd_val(pmd));
325 }
326 
327 static inline pmd_t pte_pmd(pte_t pte)
328 {
329 	return __pmd(pte_val(pte));
330 }
331 
332 static inline pgprot_t mk_sect_prot(pgprot_t prot)
333 {
334 	return __pgprot(pgprot_val(prot) & ~PTE_TABLE_BIT);
335 }
336 
337 #ifdef CONFIG_NUMA_BALANCING
338 /*
339  * See the comment in include/asm-generic/pgtable.h
340  */
341 static inline int pte_protnone(pte_t pte)
342 {
343 	return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE;
344 }
345 
346 static inline int pmd_protnone(pmd_t pmd)
347 {
348 	return pte_protnone(pmd_pte(pmd));
349 }
350 #endif
351 
352 /*
353  * THP definitions.
354  */
355 
356 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
357 #define pmd_trans_huge(pmd)	(pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT))
358 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
359 
360 #define pmd_present(pmd)	pte_present(pmd_pte(pmd))
361 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
362 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
363 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
364 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
365 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
366 #define pmd_mkwrite(pmd)	pte_pmd(pte_mkwrite(pmd_pte(pmd)))
367 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
368 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
369 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
370 #define pmd_mknotpresent(pmd)	(__pmd(pmd_val(pmd) & ~PMD_SECT_VALID))
371 
372 #define pmd_thp_or_huge(pmd)	(pmd_huge(pmd) || pmd_trans_huge(pmd))
373 
374 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
375 
376 #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
377 
378 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
379 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
380 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
381 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
382 #define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
383 
384 #define pud_write(pud)		pte_write(pud_pte(pud))
385 
386 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
387 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
388 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
389 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
390 
391 #define set_pmd_at(mm, addr, pmdp, pmd)	set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
392 
393 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
394 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
395 
396 #define __pgprot_modify(prot,mask,bits) \
397 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
398 
399 /*
400  * Mark the prot value as uncacheable and unbufferable.
401  */
402 #define pgprot_noncached(prot) \
403 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
404 #define pgprot_writecombine(prot) \
405 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
406 #define pgprot_device(prot) \
407 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
408 #define __HAVE_PHYS_MEM_ACCESS_PROT
409 struct file;
410 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
411 				     unsigned long size, pgprot_t vma_prot);
412 
413 #define pmd_none(pmd)		(!pmd_val(pmd))
414 
415 #define pmd_bad(pmd)		(!(pmd_val(pmd) & PMD_TABLE_BIT))
416 
417 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
418 				 PMD_TYPE_TABLE)
419 #define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
420 				 PMD_TYPE_SECT)
421 
422 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
423 #define pud_sect(pud)		(0)
424 #define pud_table(pud)		(1)
425 #else
426 #define pud_sect(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
427 				 PUD_TYPE_SECT)
428 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
429 				 PUD_TYPE_TABLE)
430 #endif
431 
432 extern pgd_t init_pg_dir[PTRS_PER_PGD];
433 extern pgd_t init_pg_end[];
434 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
435 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
436 extern pgd_t tramp_pg_dir[PTRS_PER_PGD];
437 
438 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
439 
440 static inline bool in_swapper_pgdir(void *addr)
441 {
442 	return ((unsigned long)addr & PAGE_MASK) ==
443 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
444 }
445 
446 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
447 {
448 #ifdef __PAGETABLE_PMD_FOLDED
449 	if (in_swapper_pgdir(pmdp)) {
450 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
451 		return;
452 	}
453 #endif /* __PAGETABLE_PMD_FOLDED */
454 
455 	WRITE_ONCE(*pmdp, pmd);
456 
457 	if (pmd_valid(pmd))
458 		dsb(ishst);
459 }
460 
461 static inline void pmd_clear(pmd_t *pmdp)
462 {
463 	set_pmd(pmdp, __pmd(0));
464 }
465 
466 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
467 {
468 	return __pmd_to_phys(pmd);
469 }
470 
471 /* Find an entry in the third-level page table. */
472 #define pte_index(addr)		(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
473 
474 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
475 #define pte_offset_kernel(dir,addr)	((pte_t *)__va(pte_offset_phys((dir), (addr))))
476 
477 #define pte_offset_map(dir,addr)	pte_offset_kernel((dir), (addr))
478 #define pte_offset_map_nested(dir,addr)	pte_offset_kernel((dir), (addr))
479 #define pte_unmap(pte)			do { } while (0)
480 #define pte_unmap_nested(pte)		do { } while (0)
481 
482 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
483 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
484 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
485 
486 #define pmd_page(pmd)		pfn_to_page(__phys_to_pfn(__pmd_to_phys(pmd)))
487 
488 /* use ONLY for statically allocated translation tables */
489 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
490 
491 /*
492  * Conversion functions: convert a page and protection to a page entry,
493  * and a page entry and page directory to the page they refer to.
494  */
495 #define mk_pte(page,prot)	pfn_pte(page_to_pfn(page),prot)
496 
497 #if CONFIG_PGTABLE_LEVELS > 2
498 
499 #define pmd_ERROR(pmd)		__pmd_error(__FILE__, __LINE__, pmd_val(pmd))
500 
501 #define pud_none(pud)		(!pud_val(pud))
502 #define pud_bad(pud)		(!(pud_val(pud) & PUD_TABLE_BIT))
503 #define pud_present(pud)	pte_present(pud_pte(pud))
504 #define pud_valid(pud)		pte_valid(pud_pte(pud))
505 
506 static inline void set_pud(pud_t *pudp, pud_t pud)
507 {
508 #ifdef __PAGETABLE_PUD_FOLDED
509 	if (in_swapper_pgdir(pudp)) {
510 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
511 		return;
512 	}
513 #endif /* __PAGETABLE_PUD_FOLDED */
514 
515 	WRITE_ONCE(*pudp, pud);
516 
517 	if (pud_valid(pud))
518 		dsb(ishst);
519 }
520 
521 static inline void pud_clear(pud_t *pudp)
522 {
523 	set_pud(pudp, __pud(0));
524 }
525 
526 static inline phys_addr_t pud_page_paddr(pud_t pud)
527 {
528 	return __pud_to_phys(pud);
529 }
530 
531 /* Find an entry in the second-level page table. */
532 #define pmd_index(addr)		(((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
533 
534 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
535 #define pmd_offset(dir, addr)		((pmd_t *)__va(pmd_offset_phys((dir), (addr))))
536 
537 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
538 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
539 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
540 
541 #define pud_page(pud)		pfn_to_page(__phys_to_pfn(__pud_to_phys(pud)))
542 
543 /* use ONLY for statically allocated translation tables */
544 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
545 
546 #else
547 
548 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
549 
550 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
551 #define pmd_set_fixmap(addr)		NULL
552 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
553 #define pmd_clear_fixmap()
554 
555 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
556 
557 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
558 
559 #if CONFIG_PGTABLE_LEVELS > 3
560 
561 #define pud_ERROR(pud)		__pud_error(__FILE__, __LINE__, pud_val(pud))
562 
563 #define pgd_none(pgd)		(!pgd_val(pgd))
564 #define pgd_bad(pgd)		(!(pgd_val(pgd) & 2))
565 #define pgd_present(pgd)	(pgd_val(pgd))
566 
567 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
568 {
569 	if (in_swapper_pgdir(pgdp)) {
570 		set_swapper_pgd(pgdp, pgd);
571 		return;
572 	}
573 
574 	WRITE_ONCE(*pgdp, pgd);
575 	dsb(ishst);
576 }
577 
578 static inline void pgd_clear(pgd_t *pgdp)
579 {
580 	set_pgd(pgdp, __pgd(0));
581 }
582 
583 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
584 {
585 	return __pgd_to_phys(pgd);
586 }
587 
588 /* Find an entry in the frst-level page table. */
589 #define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
590 
591 #define pud_offset_phys(dir, addr)	(pgd_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t))
592 #define pud_offset(dir, addr)		((pud_t *)__va(pud_offset_phys((dir), (addr))))
593 
594 #define pud_set_fixmap(addr)		((pud_t *)set_fixmap_offset(FIX_PUD, addr))
595 #define pud_set_fixmap_offset(pgd, addr)	pud_set_fixmap(pud_offset_phys(pgd, addr))
596 #define pud_clear_fixmap()		clear_fixmap(FIX_PUD)
597 
598 #define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
599 
600 /* use ONLY for statically allocated translation tables */
601 #define pud_offset_kimg(dir,addr)	((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr))))
602 
603 #else
604 
605 #define pgd_page_paddr(pgd)	({ BUILD_BUG(); 0;})
606 
607 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
608 #define pud_set_fixmap(addr)		NULL
609 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
610 #define pud_clear_fixmap()
611 
612 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
613 
614 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
615 
616 #define pgd_ERROR(pgd)		__pgd_error(__FILE__, __LINE__, pgd_val(pgd))
617 
618 /* to find an entry in a page-table-directory */
619 #define pgd_index(addr)		(((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
620 
621 #define pgd_offset_raw(pgd, addr)	((pgd) + pgd_index(addr))
622 
623 #define pgd_offset(mm, addr)	(pgd_offset_raw((mm)->pgd, (addr)))
624 
625 /* to find an entry in a kernel page-table-directory */
626 #define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
627 
628 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
629 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
630 
631 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
632 {
633 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
634 			      PTE_PROT_NONE | PTE_VALID | PTE_WRITE;
635 	/* preserve the hardware dirty information */
636 	if (pte_hw_dirty(pte))
637 		pte = pte_mkdirty(pte);
638 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
639 	return pte;
640 }
641 
642 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
643 {
644 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
645 }
646 
647 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
648 extern int ptep_set_access_flags(struct vm_area_struct *vma,
649 				 unsigned long address, pte_t *ptep,
650 				 pte_t entry, int dirty);
651 
652 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
653 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
654 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
655 					unsigned long address, pmd_t *pmdp,
656 					pmd_t entry, int dirty)
657 {
658 	return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
659 }
660 #endif
661 
662 /*
663  * Atomic pte/pmd modifications.
664  */
665 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
666 static inline int __ptep_test_and_clear_young(pte_t *ptep)
667 {
668 	pte_t old_pte, pte;
669 
670 	pte = READ_ONCE(*ptep);
671 	do {
672 		old_pte = pte;
673 		pte = pte_mkold(pte);
674 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
675 					       pte_val(old_pte), pte_val(pte));
676 	} while (pte_val(pte) != pte_val(old_pte));
677 
678 	return pte_young(pte);
679 }
680 
681 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
682 					    unsigned long address,
683 					    pte_t *ptep)
684 {
685 	return __ptep_test_and_clear_young(ptep);
686 }
687 
688 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
689 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
690 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
691 					    unsigned long address,
692 					    pmd_t *pmdp)
693 {
694 	return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
695 }
696 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
697 
698 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
699 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
700 				       unsigned long address, pte_t *ptep)
701 {
702 	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
703 }
704 
705 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
706 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
707 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
708 					    unsigned long address, pmd_t *pmdp)
709 {
710 	return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
711 }
712 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
713 
714 /*
715  * ptep_set_wrprotect - mark read-only while trasferring potential hardware
716  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
717  */
718 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
719 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
720 {
721 	pte_t old_pte, pte;
722 
723 	pte = READ_ONCE(*ptep);
724 	do {
725 		old_pte = pte;
726 		/*
727 		 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
728 		 * clear), set the PTE_DIRTY bit.
729 		 */
730 		if (pte_hw_dirty(pte))
731 			pte = pte_mkdirty(pte);
732 		pte = pte_wrprotect(pte);
733 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
734 					       pte_val(old_pte), pte_val(pte));
735 	} while (pte_val(pte) != pte_val(old_pte));
736 }
737 
738 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
739 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
740 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
741 				      unsigned long address, pmd_t *pmdp)
742 {
743 	ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
744 }
745 
746 #define pmdp_establish pmdp_establish
747 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
748 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
749 {
750 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
751 }
752 #endif
753 
754 /*
755  * Encode and decode a swap entry:
756  *	bits 0-1:	present (must be zero)
757  *	bits 2-7:	swap type
758  *	bits 8-57:	swap offset
759  *	bit  58:	PTE_PROT_NONE (must be zero)
760  */
761 #define __SWP_TYPE_SHIFT	2
762 #define __SWP_TYPE_BITS		6
763 #define __SWP_OFFSET_BITS	50
764 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
765 #define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
766 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
767 
768 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
769 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
770 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
771 
772 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
773 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
774 
775 /*
776  * Ensure that there are not more swap files than can be encoded in the kernel
777  * PTEs.
778  */
779 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
780 
781 extern int kern_addr_valid(unsigned long addr);
782 
783 #include <asm-generic/pgtable.h>
784 
785 void pgd_cache_init(void);
786 #define pgtable_cache_init	pgd_cache_init
787 
788 /*
789  * On AArch64, the cache coherency is handled via the set_pte_at() function.
790  */
791 static inline void update_mmu_cache(struct vm_area_struct *vma,
792 				    unsigned long addr, pte_t *ptep)
793 {
794 	/*
795 	 * We don't do anything here, so there's a very small chance of
796 	 * us retaking a user fault which we just fixed up. The alternative
797 	 * is doing a dsb(ishst), but that penalises the fastpath.
798 	 */
799 }
800 
801 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
802 
803 #define kc_vaddr_to_offset(v)	((v) & ~VA_START)
804 #define kc_offset_to_vaddr(o)	((o) | VA_START)
805 
806 #ifdef CONFIG_ARM64_PA_BITS_52
807 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
808 #else
809 #define phys_to_ttbr(addr)	(addr)
810 #endif
811 
812 #endif /* !__ASSEMBLY__ */
813 
814 #endif /* __ASM_PGTABLE_H */
815