xref: /openbmc/linux/arch/riscv/include/asm/pgtable.h (revision 2dd6532e)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012 Regents of the University of California
4  */
5 
6 #ifndef _ASM_RISCV_PGTABLE_H
7 #define _ASM_RISCV_PGTABLE_H
8 
9 #include <linux/mmzone.h>
10 #include <linux/sizes.h>
11 
12 #include <asm/pgtable-bits.h>
13 
14 #ifndef CONFIG_MMU
15 #define KERNEL_LINK_ADDR	PAGE_OFFSET
16 #define KERN_VIRT_SIZE		(UL(-1))
17 #else
18 
19 #define ADDRESS_SPACE_END	(UL(-1))
20 
21 #ifdef CONFIG_64BIT
22 /* Leave 2GB for kernel and BPF at the end of the address space */
23 #define KERNEL_LINK_ADDR	(ADDRESS_SPACE_END - SZ_2G + 1)
24 #else
25 #define KERNEL_LINK_ADDR	PAGE_OFFSET
26 #endif
27 
28 /* Number of entries in the page global directory */
29 #define PTRS_PER_PGD    (PAGE_SIZE / sizeof(pgd_t))
30 /* Number of entries in the page table */
31 #define PTRS_PER_PTE    (PAGE_SIZE / sizeof(pte_t))
32 
33 /*
34  * Half of the kernel address space (half of the entries of the page global
35  * directory) is for the direct mapping.
36  */
37 #define KERN_VIRT_SIZE          ((PTRS_PER_PGD / 2 * PGDIR_SIZE) / 2)
38 
39 #define VMALLOC_SIZE     (KERN_VIRT_SIZE >> 1)
40 #define VMALLOC_END      PAGE_OFFSET
41 #define VMALLOC_START    (PAGE_OFFSET - VMALLOC_SIZE)
42 
43 #define BPF_JIT_REGION_SIZE	(SZ_128M)
44 #ifdef CONFIG_64BIT
45 #define BPF_JIT_REGION_START	(BPF_JIT_REGION_END - BPF_JIT_REGION_SIZE)
46 #define BPF_JIT_REGION_END	(MODULES_END)
47 #else
48 #define BPF_JIT_REGION_START	(PAGE_OFFSET - BPF_JIT_REGION_SIZE)
49 #define BPF_JIT_REGION_END	(VMALLOC_END)
50 #endif
51 
52 /* Modules always live before the kernel */
53 #ifdef CONFIG_64BIT
54 /* This is used to define the end of the KASAN shadow region */
55 #define MODULES_LOWEST_VADDR	(KERNEL_LINK_ADDR - SZ_2G)
56 #define MODULES_VADDR		(PFN_ALIGN((unsigned long)&_end) - SZ_2G)
57 #define MODULES_END		(PFN_ALIGN((unsigned long)&_start))
58 #endif
59 
60 /*
61  * Roughly size the vmemmap space to be large enough to fit enough
62  * struct pages to map half the virtual address space. Then
63  * position vmemmap directly below the VMALLOC region.
64  */
65 #ifdef CONFIG_64BIT
66 #define VA_BITS		(pgtable_l5_enabled ? \
67 				57 : (pgtable_l4_enabled ? 48 : 39))
68 #else
69 #define VA_BITS		32
70 #endif
71 
72 #define VMEMMAP_SHIFT \
73 	(VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT)
74 #define VMEMMAP_SIZE	BIT(VMEMMAP_SHIFT)
75 #define VMEMMAP_END	VMALLOC_START
76 #define VMEMMAP_START	(VMALLOC_START - VMEMMAP_SIZE)
77 
78 /*
79  * Define vmemmap for pfn_to_page & page_to_pfn calls. Needed if kernel
80  * is configured with CONFIG_SPARSEMEM_VMEMMAP enabled.
81  */
82 #define vmemmap		((struct page *)VMEMMAP_START)
83 
84 #define PCI_IO_SIZE      SZ_16M
85 #define PCI_IO_END       VMEMMAP_START
86 #define PCI_IO_START     (PCI_IO_END - PCI_IO_SIZE)
87 
88 #define FIXADDR_TOP      PCI_IO_START
89 #ifdef CONFIG_64BIT
90 #define FIXADDR_SIZE     PMD_SIZE
91 #else
92 #define FIXADDR_SIZE     PGDIR_SIZE
93 #endif
94 #define FIXADDR_START    (FIXADDR_TOP - FIXADDR_SIZE)
95 
96 #endif
97 
98 #ifdef CONFIG_XIP_KERNEL
99 #define XIP_OFFSET		SZ_32M
100 #define XIP_OFFSET_MASK		(SZ_32M - 1)
101 #else
102 #define XIP_OFFSET		0
103 #endif
104 
105 #ifndef __ASSEMBLY__
106 
107 #include <asm/page.h>
108 #include <asm/tlbflush.h>
109 #include <linux/mm_types.h>
110 
111 #define __page_val_to_pfn(_val)  (((_val) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT)
112 
113 #ifdef CONFIG_64BIT
114 #include <asm/pgtable-64.h>
115 #else
116 #include <asm/pgtable-32.h>
117 #endif /* CONFIG_64BIT */
118 
119 #include <linux/page_table_check.h>
120 
121 #ifdef CONFIG_XIP_KERNEL
122 #define XIP_FIXUP(addr) ({							\
123 	uintptr_t __a = (uintptr_t)(addr);					\
124 	(__a >= CONFIG_XIP_PHYS_ADDR && \
125 	 __a < CONFIG_XIP_PHYS_ADDR + XIP_OFFSET * 2) ?	\
126 		__a - CONFIG_XIP_PHYS_ADDR + CONFIG_PHYS_RAM_BASE - XIP_OFFSET :\
127 		__a;								\
128 	})
129 #else
130 #define XIP_FIXUP(addr)		(addr)
131 #endif /* CONFIG_XIP_KERNEL */
132 
133 struct pt_alloc_ops {
134 	pte_t *(*get_pte_virt)(phys_addr_t pa);
135 	phys_addr_t (*alloc_pte)(uintptr_t va);
136 #ifndef __PAGETABLE_PMD_FOLDED
137 	pmd_t *(*get_pmd_virt)(phys_addr_t pa);
138 	phys_addr_t (*alloc_pmd)(uintptr_t va);
139 	pud_t *(*get_pud_virt)(phys_addr_t pa);
140 	phys_addr_t (*alloc_pud)(uintptr_t va);
141 	p4d_t *(*get_p4d_virt)(phys_addr_t pa);
142 	phys_addr_t (*alloc_p4d)(uintptr_t va);
143 #endif
144 };
145 
146 extern struct pt_alloc_ops pt_ops __initdata;
147 
148 #ifdef CONFIG_MMU
149 /* Number of PGD entries that a user-mode program can use */
150 #define USER_PTRS_PER_PGD   (TASK_SIZE / PGDIR_SIZE)
151 
152 /* Page protection bits */
153 #define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_USER)
154 
155 #define PAGE_NONE		__pgprot(_PAGE_PROT_NONE | _PAGE_READ)
156 #define PAGE_READ		__pgprot(_PAGE_BASE | _PAGE_READ)
157 #define PAGE_WRITE		__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE)
158 #define PAGE_EXEC		__pgprot(_PAGE_BASE | _PAGE_EXEC)
159 #define PAGE_READ_EXEC		__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_EXEC)
160 #define PAGE_WRITE_EXEC		__pgprot(_PAGE_BASE | _PAGE_READ |	\
161 					 _PAGE_EXEC | _PAGE_WRITE)
162 
163 #define PAGE_COPY		PAGE_READ
164 #define PAGE_COPY_EXEC		PAGE_EXEC
165 #define PAGE_COPY_READ_EXEC	PAGE_READ_EXEC
166 #define PAGE_SHARED		PAGE_WRITE
167 #define PAGE_SHARED_EXEC	PAGE_WRITE_EXEC
168 
169 #define _PAGE_KERNEL		(_PAGE_READ \
170 				| _PAGE_WRITE \
171 				| _PAGE_PRESENT \
172 				| _PAGE_ACCESSED \
173 				| _PAGE_DIRTY \
174 				| _PAGE_GLOBAL)
175 
176 #define PAGE_KERNEL		__pgprot(_PAGE_KERNEL)
177 #define PAGE_KERNEL_READ	__pgprot(_PAGE_KERNEL & ~_PAGE_WRITE)
178 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL | _PAGE_EXEC)
179 #define PAGE_KERNEL_READ_EXEC	__pgprot((_PAGE_KERNEL & ~_PAGE_WRITE) \
180 					 | _PAGE_EXEC)
181 
182 #define PAGE_TABLE		__pgprot(_PAGE_TABLE)
183 
184 #define _PAGE_IOREMAP	((_PAGE_KERNEL & ~_PAGE_MTMASK) | _PAGE_IO)
185 #define PAGE_KERNEL_IO		__pgprot(_PAGE_IOREMAP)
186 
187 extern pgd_t swapper_pg_dir[];
188 
189 /* MAP_PRIVATE permissions: xwr (copy-on-write) */
190 #define __P000	PAGE_NONE
191 #define __P001	PAGE_READ
192 #define __P010	PAGE_COPY
193 #define __P011	PAGE_COPY
194 #define __P100	PAGE_EXEC
195 #define __P101	PAGE_READ_EXEC
196 #define __P110	PAGE_COPY_EXEC
197 #define __P111	PAGE_COPY_READ_EXEC
198 
199 /* MAP_SHARED permissions: xwr */
200 #define __S000	PAGE_NONE
201 #define __S001	PAGE_READ
202 #define __S010	PAGE_SHARED
203 #define __S011	PAGE_SHARED
204 #define __S100	PAGE_EXEC
205 #define __S101	PAGE_READ_EXEC
206 #define __S110	PAGE_SHARED_EXEC
207 #define __S111	PAGE_SHARED_EXEC
208 
209 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
210 static inline int pmd_present(pmd_t pmd)
211 {
212 	/*
213 	 * Checking for _PAGE_LEAF is needed too because:
214 	 * When splitting a THP, split_huge_page() will temporarily clear
215 	 * the present bit, in this situation, pmd_present() and
216 	 * pmd_trans_huge() still needs to return true.
217 	 */
218 	return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE | _PAGE_LEAF));
219 }
220 #else
221 static inline int pmd_present(pmd_t pmd)
222 {
223 	return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
224 }
225 #endif
226 
227 static inline int pmd_none(pmd_t pmd)
228 {
229 	return (pmd_val(pmd) == 0);
230 }
231 
232 static inline int pmd_bad(pmd_t pmd)
233 {
234 	return !pmd_present(pmd) || (pmd_val(pmd) & _PAGE_LEAF);
235 }
236 
237 #define pmd_leaf	pmd_leaf
238 static inline int pmd_leaf(pmd_t pmd)
239 {
240 	return pmd_present(pmd) && (pmd_val(pmd) & _PAGE_LEAF);
241 }
242 
243 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
244 {
245 	*pmdp = pmd;
246 }
247 
248 static inline void pmd_clear(pmd_t *pmdp)
249 {
250 	set_pmd(pmdp, __pmd(0));
251 }
252 
253 static inline pgd_t pfn_pgd(unsigned long pfn, pgprot_t prot)
254 {
255 	unsigned long prot_val = pgprot_val(prot);
256 
257 	ALT_THEAD_PMA(prot_val);
258 
259 	return __pgd((pfn << _PAGE_PFN_SHIFT) | prot_val);
260 }
261 
262 static inline unsigned long _pgd_pfn(pgd_t pgd)
263 {
264 	return pgd_val(pgd) >> _PAGE_PFN_SHIFT;
265 }
266 
267 static inline struct page *pmd_page(pmd_t pmd)
268 {
269 	return pfn_to_page(__page_val_to_pfn(pmd_val(pmd)));
270 }
271 
272 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
273 {
274 	return (unsigned long)pfn_to_virt(__page_val_to_pfn(pmd_val(pmd)));
275 }
276 
277 static inline pte_t pmd_pte(pmd_t pmd)
278 {
279 	return __pte(pmd_val(pmd));
280 }
281 
282 static inline pte_t pud_pte(pud_t pud)
283 {
284 	return __pte(pud_val(pud));
285 }
286 
287 /* Yields the page frame number (PFN) of a page table entry */
288 static inline unsigned long pte_pfn(pte_t pte)
289 {
290 	return __page_val_to_pfn(pte_val(pte));
291 }
292 
293 #define pte_page(x)     pfn_to_page(pte_pfn(x))
294 
295 /* Constructs a page table entry */
296 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot)
297 {
298 	unsigned long prot_val = pgprot_val(prot);
299 
300 	ALT_THEAD_PMA(prot_val);
301 
302 	return __pte((pfn << _PAGE_PFN_SHIFT) | prot_val);
303 }
304 
305 #define mk_pte(page, prot)       pfn_pte(page_to_pfn(page), prot)
306 
307 static inline int pte_present(pte_t pte)
308 {
309 	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
310 }
311 
312 static inline int pte_none(pte_t pte)
313 {
314 	return (pte_val(pte) == 0);
315 }
316 
317 static inline int pte_write(pte_t pte)
318 {
319 	return pte_val(pte) & _PAGE_WRITE;
320 }
321 
322 static inline int pte_exec(pte_t pte)
323 {
324 	return pte_val(pte) & _PAGE_EXEC;
325 }
326 
327 static inline int pte_user(pte_t pte)
328 {
329 	return pte_val(pte) & _PAGE_USER;
330 }
331 
332 static inline int pte_huge(pte_t pte)
333 {
334 	return pte_present(pte) && (pte_val(pte) & _PAGE_LEAF);
335 }
336 
337 static inline int pte_dirty(pte_t pte)
338 {
339 	return pte_val(pte) & _PAGE_DIRTY;
340 }
341 
342 static inline int pte_young(pte_t pte)
343 {
344 	return pte_val(pte) & _PAGE_ACCESSED;
345 }
346 
347 static inline int pte_special(pte_t pte)
348 {
349 	return pte_val(pte) & _PAGE_SPECIAL;
350 }
351 
352 /* static inline pte_t pte_rdprotect(pte_t pte) */
353 
354 static inline pte_t pte_wrprotect(pte_t pte)
355 {
356 	return __pte(pte_val(pte) & ~(_PAGE_WRITE));
357 }
358 
359 /* static inline pte_t pte_mkread(pte_t pte) */
360 
361 static inline pte_t pte_mkwrite(pte_t pte)
362 {
363 	return __pte(pte_val(pte) | _PAGE_WRITE);
364 }
365 
366 /* static inline pte_t pte_mkexec(pte_t pte) */
367 
368 static inline pte_t pte_mkdirty(pte_t pte)
369 {
370 	return __pte(pte_val(pte) | _PAGE_DIRTY);
371 }
372 
373 static inline pte_t pte_mkclean(pte_t pte)
374 {
375 	return __pte(pte_val(pte) & ~(_PAGE_DIRTY));
376 }
377 
378 static inline pte_t pte_mkyoung(pte_t pte)
379 {
380 	return __pte(pte_val(pte) | _PAGE_ACCESSED);
381 }
382 
383 static inline pte_t pte_mkold(pte_t pte)
384 {
385 	return __pte(pte_val(pte) & ~(_PAGE_ACCESSED));
386 }
387 
388 static inline pte_t pte_mkspecial(pte_t pte)
389 {
390 	return __pte(pte_val(pte) | _PAGE_SPECIAL);
391 }
392 
393 static inline pte_t pte_mkhuge(pte_t pte)
394 {
395 	return pte;
396 }
397 
398 #ifdef CONFIG_NUMA_BALANCING
399 /*
400  * See the comment in include/asm-generic/pgtable.h
401  */
402 static inline int pte_protnone(pte_t pte)
403 {
404 	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE)) == _PAGE_PROT_NONE;
405 }
406 
407 static inline int pmd_protnone(pmd_t pmd)
408 {
409 	return pte_protnone(pmd_pte(pmd));
410 }
411 #endif
412 
413 /* Modify page protection bits */
414 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
415 {
416 	unsigned long newprot_val = pgprot_val(newprot);
417 
418 	ALT_THEAD_PMA(newprot_val);
419 
420 	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | newprot_val);
421 }
422 
423 #define pgd_ERROR(e) \
424 	pr_err("%s:%d: bad pgd " PTE_FMT ".\n", __FILE__, __LINE__, pgd_val(e))
425 
426 
427 /* Commit new configuration to MMU hardware */
428 static inline void update_mmu_cache(struct vm_area_struct *vma,
429 	unsigned long address, pte_t *ptep)
430 {
431 	/*
432 	 * The kernel assumes that TLBs don't cache invalid entries, but
433 	 * in RISC-V, SFENCE.VMA specifies an ordering constraint, not a
434 	 * cache flush; it is necessary even after writing invalid entries.
435 	 * Relying on flush_tlb_fix_spurious_fault would suffice, but
436 	 * the extra traps reduce performance.  So, eagerly SFENCE.VMA.
437 	 */
438 	local_flush_tlb_page(address);
439 }
440 
441 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
442 		unsigned long address, pmd_t *pmdp)
443 {
444 	pte_t *ptep = (pte_t *)pmdp;
445 
446 	update_mmu_cache(vma, address, ptep);
447 }
448 
449 #define __HAVE_ARCH_PTE_SAME
450 static inline int pte_same(pte_t pte_a, pte_t pte_b)
451 {
452 	return pte_val(pte_a) == pte_val(pte_b);
453 }
454 
455 /*
456  * Certain architectures need to do special things when PTEs within
457  * a page table are directly modified.  Thus, the following hook is
458  * made available.
459  */
460 static inline void set_pte(pte_t *ptep, pte_t pteval)
461 {
462 	*ptep = pteval;
463 }
464 
465 void flush_icache_pte(pte_t pte);
466 
467 static inline void __set_pte_at(struct mm_struct *mm,
468 	unsigned long addr, pte_t *ptep, pte_t pteval)
469 {
470 	if (pte_present(pteval) && pte_exec(pteval))
471 		flush_icache_pte(pteval);
472 
473 	set_pte(ptep, pteval);
474 }
475 
476 static inline void set_pte_at(struct mm_struct *mm,
477 	unsigned long addr, pte_t *ptep, pte_t pteval)
478 {
479 	page_table_check_pte_set(mm, addr, ptep, pteval);
480 	__set_pte_at(mm, addr, ptep, pteval);
481 }
482 
483 static inline void pte_clear(struct mm_struct *mm,
484 	unsigned long addr, pte_t *ptep)
485 {
486 	__set_pte_at(mm, addr, ptep, __pte(0));
487 }
488 
489 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
490 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
491 					unsigned long address, pte_t *ptep,
492 					pte_t entry, int dirty)
493 {
494 	if (!pte_same(*ptep, entry))
495 		set_pte_at(vma->vm_mm, address, ptep, entry);
496 	/*
497 	 * update_mmu_cache will unconditionally execute, handling both
498 	 * the case that the PTE changed and the spurious fault case.
499 	 */
500 	return true;
501 }
502 
503 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
504 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
505 				       unsigned long address, pte_t *ptep)
506 {
507 	pte_t pte = __pte(atomic_long_xchg((atomic_long_t *)ptep, 0));
508 
509 	page_table_check_pte_clear(mm, address, pte);
510 
511 	return pte;
512 }
513 
514 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
515 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
516 					    unsigned long address,
517 					    pte_t *ptep)
518 {
519 	if (!pte_young(*ptep))
520 		return 0;
521 	return test_and_clear_bit(_PAGE_ACCESSED_OFFSET, &pte_val(*ptep));
522 }
523 
524 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
525 static inline void ptep_set_wrprotect(struct mm_struct *mm,
526 				      unsigned long address, pte_t *ptep)
527 {
528 	atomic_long_and(~(unsigned long)_PAGE_WRITE, (atomic_long_t *)ptep);
529 }
530 
531 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
532 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
533 					 unsigned long address, pte_t *ptep)
534 {
535 	/*
536 	 * This comment is borrowed from x86, but applies equally to RISC-V:
537 	 *
538 	 * Clearing the accessed bit without a TLB flush
539 	 * doesn't cause data corruption. [ It could cause incorrect
540 	 * page aging and the (mistaken) reclaim of hot pages, but the
541 	 * chance of that should be relatively low. ]
542 	 *
543 	 * So as a performance optimization don't flush the TLB when
544 	 * clearing the accessed bit, it will eventually be flushed by
545 	 * a context switch or a VM operation anyway. [ In the rare
546 	 * event of it not getting flushed for a long time the delay
547 	 * shouldn't really matter because there's no real memory
548 	 * pressure for swapout to react to. ]
549 	 */
550 	return ptep_test_and_clear_young(vma, address, ptep);
551 }
552 
553 #define pgprot_noncached pgprot_noncached
554 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
555 {
556 	unsigned long prot = pgprot_val(_prot);
557 
558 	prot &= ~_PAGE_MTMASK;
559 	prot |= _PAGE_IO;
560 
561 	return __pgprot(prot);
562 }
563 
564 #define pgprot_writecombine pgprot_writecombine
565 static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
566 {
567 	unsigned long prot = pgprot_val(_prot);
568 
569 	prot &= ~_PAGE_MTMASK;
570 	prot |= _PAGE_NOCACHE;
571 
572 	return __pgprot(prot);
573 }
574 
575 /*
576  * THP functions
577  */
578 static inline pmd_t pte_pmd(pte_t pte)
579 {
580 	return __pmd(pte_val(pte));
581 }
582 
583 static inline pmd_t pmd_mkhuge(pmd_t pmd)
584 {
585 	return pmd;
586 }
587 
588 static inline pmd_t pmd_mkinvalid(pmd_t pmd)
589 {
590 	return __pmd(pmd_val(pmd) & ~(_PAGE_PRESENT|_PAGE_PROT_NONE));
591 }
592 
593 #define __pmd_to_phys(pmd)  (pmd_val(pmd) >> _PAGE_PFN_SHIFT << PAGE_SHIFT)
594 
595 static inline unsigned long pmd_pfn(pmd_t pmd)
596 {
597 	return ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT);
598 }
599 
600 #define __pud_to_phys(pud)  (pud_val(pud) >> _PAGE_PFN_SHIFT << PAGE_SHIFT)
601 
602 static inline unsigned long pud_pfn(pud_t pud)
603 {
604 	return ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT);
605 }
606 
607 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
608 {
609 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
610 }
611 
612 #define pmd_write pmd_write
613 static inline int pmd_write(pmd_t pmd)
614 {
615 	return pte_write(pmd_pte(pmd));
616 }
617 
618 static inline int pmd_dirty(pmd_t pmd)
619 {
620 	return pte_dirty(pmd_pte(pmd));
621 }
622 
623 static inline int pmd_young(pmd_t pmd)
624 {
625 	return pte_young(pmd_pte(pmd));
626 }
627 
628 static inline int pmd_user(pmd_t pmd)
629 {
630 	return pte_user(pmd_pte(pmd));
631 }
632 
633 static inline pmd_t pmd_mkold(pmd_t pmd)
634 {
635 	return pte_pmd(pte_mkold(pmd_pte(pmd)));
636 }
637 
638 static inline pmd_t pmd_mkyoung(pmd_t pmd)
639 {
640 	return pte_pmd(pte_mkyoung(pmd_pte(pmd)));
641 }
642 
643 static inline pmd_t pmd_mkwrite(pmd_t pmd)
644 {
645 	return pte_pmd(pte_mkwrite(pmd_pte(pmd)));
646 }
647 
648 static inline pmd_t pmd_wrprotect(pmd_t pmd)
649 {
650 	return pte_pmd(pte_wrprotect(pmd_pte(pmd)));
651 }
652 
653 static inline pmd_t pmd_mkclean(pmd_t pmd)
654 {
655 	return pte_pmd(pte_mkclean(pmd_pte(pmd)));
656 }
657 
658 static inline pmd_t pmd_mkdirty(pmd_t pmd)
659 {
660 	return pte_pmd(pte_mkdirty(pmd_pte(pmd)));
661 }
662 
663 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
664 				pmd_t *pmdp, pmd_t pmd)
665 {
666 	page_table_check_pmd_set(mm, addr, pmdp, pmd);
667 	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd));
668 }
669 
670 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
671 				pud_t *pudp, pud_t pud)
672 {
673 	page_table_check_pud_set(mm, addr, pudp, pud);
674 	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud));
675 }
676 
677 #ifdef CONFIG_PAGE_TABLE_CHECK
678 static inline bool pte_user_accessible_page(pte_t pte)
679 {
680 	return pte_present(pte) && pte_user(pte);
681 }
682 
683 static inline bool pmd_user_accessible_page(pmd_t pmd)
684 {
685 	return pmd_leaf(pmd) && pmd_user(pmd);
686 }
687 
688 static inline bool pud_user_accessible_page(pud_t pud)
689 {
690 	return pud_leaf(pud) && pud_user(pud);
691 }
692 #endif
693 
694 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
695 static inline int pmd_trans_huge(pmd_t pmd)
696 {
697 	return pmd_leaf(pmd);
698 }
699 
700 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
701 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
702 					unsigned long address, pmd_t *pmdp,
703 					pmd_t entry, int dirty)
704 {
705 	return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
706 }
707 
708 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
709 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
710 					unsigned long address, pmd_t *pmdp)
711 {
712 	return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
713 }
714 
715 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
716 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
717 					unsigned long address, pmd_t *pmdp)
718 {
719 	pmd_t pmd = __pmd(atomic_long_xchg((atomic_long_t *)pmdp, 0));
720 
721 	page_table_check_pmd_clear(mm, address, pmd);
722 
723 	return pmd;
724 }
725 
726 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
727 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
728 					unsigned long address, pmd_t *pmdp)
729 {
730 	ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
731 }
732 
733 #define pmdp_establish pmdp_establish
734 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
735 				unsigned long address, pmd_t *pmdp, pmd_t pmd)
736 {
737 	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
738 	return __pmd(atomic_long_xchg((atomic_long_t *)pmdp, pmd_val(pmd)));
739 }
740 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
741 
742 /*
743  * Encode and decode a swap entry
744  *
745  * Format of swap PTE:
746  *	bit            0:	_PAGE_PRESENT (zero)
747  *	bit       1 to 3:       _PAGE_LEAF (zero)
748  *	bit            5:	_PAGE_PROT_NONE (zero)
749  *	bits      6 to 10:	swap type
750  *	bits 10 to XLEN-1:	swap offset
751  */
752 #define __SWP_TYPE_SHIFT	6
753 #define __SWP_TYPE_BITS		5
754 #define __SWP_TYPE_MASK		((1UL << __SWP_TYPE_BITS) - 1)
755 #define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
756 
757 #define MAX_SWAPFILES_CHECK()	\
758 	BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
759 
760 #define __swp_type(x)	(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
761 #define __swp_offset(x)	((x).val >> __SWP_OFFSET_SHIFT)
762 #define __swp_entry(type, offset) ((swp_entry_t) \
763 	{ ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
764 
765 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
766 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
767 
768 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
769 #define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
770 #define __swp_entry_to_pmd(swp) __pmd((swp).val)
771 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
772 
773 /*
774  * In the RV64 Linux scheme, we give the user half of the virtual-address space
775  * and give the kernel the other (upper) half.
776  */
777 #ifdef CONFIG_64BIT
778 #define KERN_VIRT_START	(-(BIT(VA_BITS)) + TASK_SIZE)
779 #else
780 #define KERN_VIRT_START	FIXADDR_START
781 #endif
782 
783 /*
784  * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32.
785  * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
786  * Task size is:
787  * -     0x9fc00000 (~2.5GB) for RV32.
788  * -   0x4000000000 ( 256GB) for RV64 using SV39 mmu
789  * - 0x800000000000 ( 128TB) for RV64 using SV48 mmu
790  *
791  * Note that PGDIR_SIZE must evenly divide TASK_SIZE since "RISC-V
792  * Instruction Set Manual Volume II: Privileged Architecture" states that
793  * "load and store effective addresses, which are 64bits, must have bits
794  * 63–48 all equal to bit 47, or else a page-fault exception will occur."
795  */
796 #ifdef CONFIG_64BIT
797 #define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
798 #define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
799 
800 #ifdef CONFIG_COMPAT
801 #define TASK_SIZE_32	(_AC(0x80000000, UL) - PAGE_SIZE)
802 #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
803 			 TASK_SIZE_32 : TASK_SIZE_64)
804 #else
805 #define TASK_SIZE	TASK_SIZE_64
806 #endif
807 
808 #else
809 #define TASK_SIZE	FIXADDR_START
810 #define TASK_SIZE_MIN	TASK_SIZE
811 #endif
812 
813 #else /* CONFIG_MMU */
814 
815 #define PAGE_SHARED		__pgprot(0)
816 #define PAGE_KERNEL		__pgprot(0)
817 #define swapper_pg_dir		NULL
818 #define TASK_SIZE		0xffffffffUL
819 #define VMALLOC_START		0
820 #define VMALLOC_END		TASK_SIZE
821 
822 #endif /* !CONFIG_MMU */
823 
824 #define kern_addr_valid(addr)   (1) /* FIXME */
825 
826 extern char _start[];
827 extern void *_dtb_early_va;
828 extern uintptr_t _dtb_early_pa;
829 #if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_MMU)
830 #define dtb_early_va	(*(void **)XIP_FIXUP(&_dtb_early_va))
831 #define dtb_early_pa	(*(uintptr_t *)XIP_FIXUP(&_dtb_early_pa))
832 #else
833 #define dtb_early_va	_dtb_early_va
834 #define dtb_early_pa	_dtb_early_pa
835 #endif /* CONFIG_XIP_KERNEL */
836 extern u64 satp_mode;
837 extern bool pgtable_l4_enabled;
838 
839 void paging_init(void);
840 void misc_mem_init(void);
841 
842 /*
843  * ZERO_PAGE is a global shared page that is always zero,
844  * used for zero-mapped memory areas, etc.
845  */
846 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
847 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
848 
849 #endif /* !__ASSEMBLY__ */
850 
851 #endif /* _ASM_RISCV_PGTABLE_H */
852