xref: /linux/arch/riscv/include/asm/pgtable.h (revision f8941e6c4c712948663ec5d7bbb546f1a0f4e3f6)
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 (1/4 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 MAX_FDT_SIZE	 PMD_SIZE
91 #define FIX_FDT_SIZE	 (MAX_FDT_SIZE + SZ_2M)
92 #define FIXADDR_SIZE     (PMD_SIZE + FIX_FDT_SIZE)
93 #else
94 #define MAX_FDT_SIZE	 PGDIR_SIZE
95 #define FIX_FDT_SIZE	 MAX_FDT_SIZE
96 #define FIXADDR_SIZE     (PGDIR_SIZE + FIX_FDT_SIZE)
97 #endif
98 #define FIXADDR_START    (FIXADDR_TOP - FIXADDR_SIZE)
99 
100 #endif
101 
102 #ifdef CONFIG_XIP_KERNEL
103 #define XIP_OFFSET		SZ_32M
104 #define XIP_OFFSET_MASK		(SZ_32M - 1)
105 #else
106 #define XIP_OFFSET		0
107 #endif
108 
109 #ifndef __ASSEMBLY__
110 
111 #include <asm/page.h>
112 #include <asm/tlbflush.h>
113 #include <linux/mm_types.h>
114 
115 #define __page_val_to_pfn(_val)  (((_val) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT)
116 
117 #ifdef CONFIG_64BIT
118 #include <asm/pgtable-64.h>
119 #else
120 #include <asm/pgtable-32.h>
121 #endif /* CONFIG_64BIT */
122 
123 #include <linux/page_table_check.h>
124 
125 #ifdef CONFIG_XIP_KERNEL
126 #define XIP_FIXUP(addr) ({							\
127 	uintptr_t __a = (uintptr_t)(addr);					\
128 	(__a >= CONFIG_XIP_PHYS_ADDR && \
129 	 __a < CONFIG_XIP_PHYS_ADDR + XIP_OFFSET * 2) ?	\
130 		__a - CONFIG_XIP_PHYS_ADDR + CONFIG_PHYS_RAM_BASE - XIP_OFFSET :\
131 		__a;								\
132 	})
133 #else
134 #define XIP_FIXUP(addr)		(addr)
135 #endif /* CONFIG_XIP_KERNEL */
136 
137 struct pt_alloc_ops {
138 	pte_t *(*get_pte_virt)(phys_addr_t pa);
139 	phys_addr_t (*alloc_pte)(uintptr_t va);
140 #ifndef __PAGETABLE_PMD_FOLDED
141 	pmd_t *(*get_pmd_virt)(phys_addr_t pa);
142 	phys_addr_t (*alloc_pmd)(uintptr_t va);
143 	pud_t *(*get_pud_virt)(phys_addr_t pa);
144 	phys_addr_t (*alloc_pud)(uintptr_t va);
145 	p4d_t *(*get_p4d_virt)(phys_addr_t pa);
146 	phys_addr_t (*alloc_p4d)(uintptr_t va);
147 #endif
148 };
149 
150 extern struct pt_alloc_ops pt_ops __initdata;
151 
152 #ifdef CONFIG_MMU
153 /* Number of PGD entries that a user-mode program can use */
154 #define USER_PTRS_PER_PGD   (TASK_SIZE / PGDIR_SIZE)
155 
156 /* Page protection bits */
157 #define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_USER)
158 
159 #define PAGE_NONE		__pgprot(_PAGE_PROT_NONE | _PAGE_READ)
160 #define PAGE_READ		__pgprot(_PAGE_BASE | _PAGE_READ)
161 #define PAGE_WRITE		__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE)
162 #define PAGE_EXEC		__pgprot(_PAGE_BASE | _PAGE_EXEC)
163 #define PAGE_READ_EXEC		__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_EXEC)
164 #define PAGE_WRITE_EXEC		__pgprot(_PAGE_BASE | _PAGE_READ |	\
165 					 _PAGE_EXEC | _PAGE_WRITE)
166 
167 #define PAGE_COPY		PAGE_READ
168 #define PAGE_COPY_EXEC		PAGE_READ_EXEC
169 #define PAGE_SHARED		PAGE_WRITE
170 #define PAGE_SHARED_EXEC	PAGE_WRITE_EXEC
171 
172 #define _PAGE_KERNEL		(_PAGE_READ \
173 				| _PAGE_WRITE \
174 				| _PAGE_PRESENT \
175 				| _PAGE_ACCESSED \
176 				| _PAGE_DIRTY \
177 				| _PAGE_GLOBAL)
178 
179 #define PAGE_KERNEL		__pgprot(_PAGE_KERNEL)
180 #define PAGE_KERNEL_READ	__pgprot(_PAGE_KERNEL & ~_PAGE_WRITE)
181 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL | _PAGE_EXEC)
182 #define PAGE_KERNEL_READ_EXEC	__pgprot((_PAGE_KERNEL & ~_PAGE_WRITE) \
183 					 | _PAGE_EXEC)
184 
185 #define PAGE_TABLE		__pgprot(_PAGE_TABLE)
186 
187 #define _PAGE_IOREMAP	((_PAGE_KERNEL & ~_PAGE_MTMASK) | _PAGE_IO)
188 #define PAGE_KERNEL_IO		__pgprot(_PAGE_IOREMAP)
189 
190 extern pgd_t swapper_pg_dir[];
191 extern pgd_t trampoline_pg_dir[];
192 extern pgd_t early_pg_dir[];
193 
194 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
195 static inline int pmd_present(pmd_t pmd)
196 {
197 	/*
198 	 * Checking for _PAGE_LEAF is needed too because:
199 	 * When splitting a THP, split_huge_page() will temporarily clear
200 	 * the present bit, in this situation, pmd_present() and
201 	 * pmd_trans_huge() still needs to return true.
202 	 */
203 	return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE | _PAGE_LEAF));
204 }
205 #else
206 static inline int pmd_present(pmd_t pmd)
207 {
208 	return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
209 }
210 #endif
211 
212 static inline int pmd_none(pmd_t pmd)
213 {
214 	return (pmd_val(pmd) == 0);
215 }
216 
217 static inline int pmd_bad(pmd_t pmd)
218 {
219 	return !pmd_present(pmd) || (pmd_val(pmd) & _PAGE_LEAF);
220 }
221 
222 #define pmd_leaf	pmd_leaf
223 static inline int pmd_leaf(pmd_t pmd)
224 {
225 	return pmd_present(pmd) && (pmd_val(pmd) & _PAGE_LEAF);
226 }
227 
228 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
229 {
230 	*pmdp = pmd;
231 }
232 
233 static inline void pmd_clear(pmd_t *pmdp)
234 {
235 	set_pmd(pmdp, __pmd(0));
236 }
237 
238 static inline pgd_t pfn_pgd(unsigned long pfn, pgprot_t prot)
239 {
240 	unsigned long prot_val = pgprot_val(prot);
241 
242 	ALT_THEAD_PMA(prot_val);
243 
244 	return __pgd((pfn << _PAGE_PFN_SHIFT) | prot_val);
245 }
246 
247 static inline unsigned long _pgd_pfn(pgd_t pgd)
248 {
249 	return __page_val_to_pfn(pgd_val(pgd));
250 }
251 
252 static inline struct page *pmd_page(pmd_t pmd)
253 {
254 	return pfn_to_page(__page_val_to_pfn(pmd_val(pmd)));
255 }
256 
257 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
258 {
259 	return (unsigned long)pfn_to_virt(__page_val_to_pfn(pmd_val(pmd)));
260 }
261 
262 static inline pte_t pmd_pte(pmd_t pmd)
263 {
264 	return __pte(pmd_val(pmd));
265 }
266 
267 static inline pte_t pud_pte(pud_t pud)
268 {
269 	return __pte(pud_val(pud));
270 }
271 
272 #ifdef CONFIG_RISCV_ISA_SVNAPOT
273 
274 static __always_inline bool has_svnapot(void)
275 {
276 	return riscv_has_extension_likely(RISCV_ISA_EXT_SVNAPOT);
277 }
278 
279 static inline unsigned long pte_napot(pte_t pte)
280 {
281 	return pte_val(pte) & _PAGE_NAPOT;
282 }
283 
284 static inline pte_t pte_mknapot(pte_t pte, unsigned int order)
285 {
286 	int pos = order - 1 + _PAGE_PFN_SHIFT;
287 	unsigned long napot_bit = BIT(pos);
288 	unsigned long napot_mask = ~GENMASK(pos, _PAGE_PFN_SHIFT);
289 
290 	return __pte((pte_val(pte) & napot_mask) | napot_bit | _PAGE_NAPOT);
291 }
292 
293 #else
294 
295 static __always_inline bool has_svnapot(void) { return false; }
296 
297 static inline unsigned long pte_napot(pte_t pte)
298 {
299 	return 0;
300 }
301 
302 #endif /* CONFIG_RISCV_ISA_SVNAPOT */
303 
304 /* Yields the page frame number (PFN) of a page table entry */
305 static inline unsigned long pte_pfn(pte_t pte)
306 {
307 	unsigned long res  = __page_val_to_pfn(pte_val(pte));
308 
309 	if (has_svnapot() && pte_napot(pte))
310 		res = res & (res - 1UL);
311 
312 	return res;
313 }
314 
315 #define pte_page(x)     pfn_to_page(pte_pfn(x))
316 
317 /* Constructs a page table entry */
318 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot)
319 {
320 	unsigned long prot_val = pgprot_val(prot);
321 
322 	ALT_THEAD_PMA(prot_val);
323 
324 	return __pte((pfn << _PAGE_PFN_SHIFT) | prot_val);
325 }
326 
327 #define mk_pte(page, prot)       pfn_pte(page_to_pfn(page), prot)
328 
329 static inline int pte_present(pte_t pte)
330 {
331 	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
332 }
333 
334 static inline int pte_none(pte_t pte)
335 {
336 	return (pte_val(pte) == 0);
337 }
338 
339 static inline int pte_write(pte_t pte)
340 {
341 	return pte_val(pte) & _PAGE_WRITE;
342 }
343 
344 static inline int pte_exec(pte_t pte)
345 {
346 	return pte_val(pte) & _PAGE_EXEC;
347 }
348 
349 static inline int pte_user(pte_t pte)
350 {
351 	return pte_val(pte) & _PAGE_USER;
352 }
353 
354 static inline int pte_huge(pte_t pte)
355 {
356 	return pte_present(pte) && (pte_val(pte) & _PAGE_LEAF);
357 }
358 
359 static inline int pte_dirty(pte_t pte)
360 {
361 	return pte_val(pte) & _PAGE_DIRTY;
362 }
363 
364 static inline int pte_young(pte_t pte)
365 {
366 	return pte_val(pte) & _PAGE_ACCESSED;
367 }
368 
369 static inline int pte_special(pte_t pte)
370 {
371 	return pte_val(pte) & _PAGE_SPECIAL;
372 }
373 
374 /* static inline pte_t pte_rdprotect(pte_t pte) */
375 
376 static inline pte_t pte_wrprotect(pte_t pte)
377 {
378 	return __pte(pte_val(pte) & ~(_PAGE_WRITE));
379 }
380 
381 /* static inline pte_t pte_mkread(pte_t pte) */
382 
383 static inline pte_t pte_mkwrite(pte_t pte)
384 {
385 	return __pte(pte_val(pte) | _PAGE_WRITE);
386 }
387 
388 /* static inline pte_t pte_mkexec(pte_t pte) */
389 
390 static inline pte_t pte_mkdirty(pte_t pte)
391 {
392 	return __pte(pte_val(pte) | _PAGE_DIRTY);
393 }
394 
395 static inline pte_t pte_mkclean(pte_t pte)
396 {
397 	return __pte(pte_val(pte) & ~(_PAGE_DIRTY));
398 }
399 
400 static inline pte_t pte_mkyoung(pte_t pte)
401 {
402 	return __pte(pte_val(pte) | _PAGE_ACCESSED);
403 }
404 
405 static inline pte_t pte_mkold(pte_t pte)
406 {
407 	return __pte(pte_val(pte) & ~(_PAGE_ACCESSED));
408 }
409 
410 static inline pte_t pte_mkspecial(pte_t pte)
411 {
412 	return __pte(pte_val(pte) | _PAGE_SPECIAL);
413 }
414 
415 static inline pte_t pte_mkhuge(pte_t pte)
416 {
417 	return pte;
418 }
419 
420 #ifdef CONFIG_NUMA_BALANCING
421 /*
422  * See the comment in include/asm-generic/pgtable.h
423  */
424 static inline int pte_protnone(pte_t pte)
425 {
426 	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE)) == _PAGE_PROT_NONE;
427 }
428 
429 static inline int pmd_protnone(pmd_t pmd)
430 {
431 	return pte_protnone(pmd_pte(pmd));
432 }
433 #endif
434 
435 /* Modify page protection bits */
436 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
437 {
438 	unsigned long newprot_val = pgprot_val(newprot);
439 
440 	ALT_THEAD_PMA(newprot_val);
441 
442 	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | newprot_val);
443 }
444 
445 #define pgd_ERROR(e) \
446 	pr_err("%s:%d: bad pgd " PTE_FMT ".\n", __FILE__, __LINE__, pgd_val(e))
447 
448 
449 /* Commit new configuration to MMU hardware */
450 static inline void update_mmu_cache(struct vm_area_struct *vma,
451 	unsigned long address, pte_t *ptep)
452 {
453 	/*
454 	 * The kernel assumes that TLBs don't cache invalid entries, but
455 	 * in RISC-V, SFENCE.VMA specifies an ordering constraint, not a
456 	 * cache flush; it is necessary even after writing invalid entries.
457 	 * Relying on flush_tlb_fix_spurious_fault would suffice, but
458 	 * the extra traps reduce performance.  So, eagerly SFENCE.VMA.
459 	 */
460 	local_flush_tlb_page(address);
461 }
462 
463 #define __HAVE_ARCH_UPDATE_MMU_TLB
464 #define update_mmu_tlb update_mmu_cache
465 
466 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
467 		unsigned long address, pmd_t *pmdp)
468 {
469 	pte_t *ptep = (pte_t *)pmdp;
470 
471 	update_mmu_cache(vma, address, ptep);
472 }
473 
474 #define __HAVE_ARCH_PTE_SAME
475 static inline int pte_same(pte_t pte_a, pte_t pte_b)
476 {
477 	return pte_val(pte_a) == pte_val(pte_b);
478 }
479 
480 /*
481  * Certain architectures need to do special things when PTEs within
482  * a page table are directly modified.  Thus, the following hook is
483  * made available.
484  */
485 static inline void set_pte(pte_t *ptep, pte_t pteval)
486 {
487 	*ptep = pteval;
488 }
489 
490 void flush_icache_pte(pte_t pte);
491 
492 static inline void __set_pte_at(struct mm_struct *mm,
493 	unsigned long addr, pte_t *ptep, pte_t pteval)
494 {
495 	if (pte_present(pteval) && pte_exec(pteval))
496 		flush_icache_pte(pteval);
497 
498 	set_pte(ptep, pteval);
499 }
500 
501 static inline void set_pte_at(struct mm_struct *mm,
502 	unsigned long addr, pte_t *ptep, pte_t pteval)
503 {
504 	page_table_check_pte_set(mm, addr, ptep, pteval);
505 	__set_pte_at(mm, addr, ptep, pteval);
506 }
507 
508 static inline void pte_clear(struct mm_struct *mm,
509 	unsigned long addr, pte_t *ptep)
510 {
511 	__set_pte_at(mm, addr, ptep, __pte(0));
512 }
513 
514 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
515 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
516 					unsigned long address, pte_t *ptep,
517 					pte_t entry, int dirty)
518 {
519 	if (!pte_same(*ptep, entry))
520 		set_pte_at(vma->vm_mm, address, ptep, entry);
521 	/*
522 	 * update_mmu_cache will unconditionally execute, handling both
523 	 * the case that the PTE changed and the spurious fault case.
524 	 */
525 	return true;
526 }
527 
528 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
529 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
530 				       unsigned long address, pte_t *ptep)
531 {
532 	pte_t pte = __pte(atomic_long_xchg((atomic_long_t *)ptep, 0));
533 
534 	page_table_check_pte_clear(mm, address, pte);
535 
536 	return pte;
537 }
538 
539 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
540 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
541 					    unsigned long address,
542 					    pte_t *ptep)
543 {
544 	if (!pte_young(*ptep))
545 		return 0;
546 	return test_and_clear_bit(_PAGE_ACCESSED_OFFSET, &pte_val(*ptep));
547 }
548 
549 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
550 static inline void ptep_set_wrprotect(struct mm_struct *mm,
551 				      unsigned long address, pte_t *ptep)
552 {
553 	atomic_long_and(~(unsigned long)_PAGE_WRITE, (atomic_long_t *)ptep);
554 }
555 
556 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
557 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
558 					 unsigned long address, pte_t *ptep)
559 {
560 	/*
561 	 * This comment is borrowed from x86, but applies equally to RISC-V:
562 	 *
563 	 * Clearing the accessed bit without a TLB flush
564 	 * doesn't cause data corruption. [ It could cause incorrect
565 	 * page aging and the (mistaken) reclaim of hot pages, but the
566 	 * chance of that should be relatively low. ]
567 	 *
568 	 * So as a performance optimization don't flush the TLB when
569 	 * clearing the accessed bit, it will eventually be flushed by
570 	 * a context switch or a VM operation anyway. [ In the rare
571 	 * event of it not getting flushed for a long time the delay
572 	 * shouldn't really matter because there's no real memory
573 	 * pressure for swapout to react to. ]
574 	 */
575 	return ptep_test_and_clear_young(vma, address, ptep);
576 }
577 
578 #define pgprot_noncached pgprot_noncached
579 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
580 {
581 	unsigned long prot = pgprot_val(_prot);
582 
583 	prot &= ~_PAGE_MTMASK;
584 	prot |= _PAGE_IO;
585 
586 	return __pgprot(prot);
587 }
588 
589 #define pgprot_writecombine pgprot_writecombine
590 static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
591 {
592 	unsigned long prot = pgprot_val(_prot);
593 
594 	prot &= ~_PAGE_MTMASK;
595 	prot |= _PAGE_NOCACHE;
596 
597 	return __pgprot(prot);
598 }
599 
600 /*
601  * THP functions
602  */
603 static inline pmd_t pte_pmd(pte_t pte)
604 {
605 	return __pmd(pte_val(pte));
606 }
607 
608 static inline pmd_t pmd_mkhuge(pmd_t pmd)
609 {
610 	return pmd;
611 }
612 
613 static inline pmd_t pmd_mkinvalid(pmd_t pmd)
614 {
615 	return __pmd(pmd_val(pmd) & ~(_PAGE_PRESENT|_PAGE_PROT_NONE));
616 }
617 
618 #define __pmd_to_phys(pmd)  (__page_val_to_pfn(pmd_val(pmd)) << PAGE_SHIFT)
619 
620 static inline unsigned long pmd_pfn(pmd_t pmd)
621 {
622 	return ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT);
623 }
624 
625 #define __pud_to_phys(pud)  (__page_val_to_pfn(pud_val(pud)) << PAGE_SHIFT)
626 
627 static inline unsigned long pud_pfn(pud_t pud)
628 {
629 	return ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT);
630 }
631 
632 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
633 {
634 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
635 }
636 
637 #define pmd_write pmd_write
638 static inline int pmd_write(pmd_t pmd)
639 {
640 	return pte_write(pmd_pte(pmd));
641 }
642 
643 static inline int pmd_dirty(pmd_t pmd)
644 {
645 	return pte_dirty(pmd_pte(pmd));
646 }
647 
648 #define pmd_young pmd_young
649 static inline int pmd_young(pmd_t pmd)
650 {
651 	return pte_young(pmd_pte(pmd));
652 }
653 
654 static inline int pmd_user(pmd_t pmd)
655 {
656 	return pte_user(pmd_pte(pmd));
657 }
658 
659 static inline pmd_t pmd_mkold(pmd_t pmd)
660 {
661 	return pte_pmd(pte_mkold(pmd_pte(pmd)));
662 }
663 
664 static inline pmd_t pmd_mkyoung(pmd_t pmd)
665 {
666 	return pte_pmd(pte_mkyoung(pmd_pte(pmd)));
667 }
668 
669 static inline pmd_t pmd_mkwrite(pmd_t pmd)
670 {
671 	return pte_pmd(pte_mkwrite(pmd_pte(pmd)));
672 }
673 
674 static inline pmd_t pmd_wrprotect(pmd_t pmd)
675 {
676 	return pte_pmd(pte_wrprotect(pmd_pte(pmd)));
677 }
678 
679 static inline pmd_t pmd_mkclean(pmd_t pmd)
680 {
681 	return pte_pmd(pte_mkclean(pmd_pte(pmd)));
682 }
683 
684 static inline pmd_t pmd_mkdirty(pmd_t pmd)
685 {
686 	return pte_pmd(pte_mkdirty(pmd_pte(pmd)));
687 }
688 
689 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
690 				pmd_t *pmdp, pmd_t pmd)
691 {
692 	page_table_check_pmd_set(mm, addr, pmdp, pmd);
693 	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd));
694 }
695 
696 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
697 				pud_t *pudp, pud_t pud)
698 {
699 	page_table_check_pud_set(mm, addr, pudp, pud);
700 	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud));
701 }
702 
703 #ifdef CONFIG_PAGE_TABLE_CHECK
704 static inline bool pte_user_accessible_page(pte_t pte)
705 {
706 	return pte_present(pte) && pte_user(pte);
707 }
708 
709 static inline bool pmd_user_accessible_page(pmd_t pmd)
710 {
711 	return pmd_leaf(pmd) && pmd_user(pmd);
712 }
713 
714 static inline bool pud_user_accessible_page(pud_t pud)
715 {
716 	return pud_leaf(pud) && pud_user(pud);
717 }
718 #endif
719 
720 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
721 static inline int pmd_trans_huge(pmd_t pmd)
722 {
723 	return pmd_leaf(pmd);
724 }
725 
726 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
727 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
728 					unsigned long address, pmd_t *pmdp,
729 					pmd_t entry, int dirty)
730 {
731 	return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
732 }
733 
734 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
735 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
736 					unsigned long address, pmd_t *pmdp)
737 {
738 	return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
739 }
740 
741 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
742 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
743 					unsigned long address, pmd_t *pmdp)
744 {
745 	pmd_t pmd = __pmd(atomic_long_xchg((atomic_long_t *)pmdp, 0));
746 
747 	page_table_check_pmd_clear(mm, address, pmd);
748 
749 	return pmd;
750 }
751 
752 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
753 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
754 					unsigned long address, pmd_t *pmdp)
755 {
756 	ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
757 }
758 
759 #define pmdp_establish pmdp_establish
760 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
761 				unsigned long address, pmd_t *pmdp, pmd_t pmd)
762 {
763 	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
764 	return __pmd(atomic_long_xchg((atomic_long_t *)pmdp, pmd_val(pmd)));
765 }
766 
767 #define pmdp_collapse_flush pmdp_collapse_flush
768 extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
769 				 unsigned long address, pmd_t *pmdp);
770 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
771 
772 /*
773  * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
774  * are !pte_none() && !pte_present().
775  *
776  * Format of swap PTE:
777  *	bit            0:	_PAGE_PRESENT (zero)
778  *	bit       1 to 3:       _PAGE_LEAF (zero)
779  *	bit            5:	_PAGE_PROT_NONE (zero)
780  *	bit            6:	exclusive marker
781  *	bits      7 to 11:	swap type
782  *	bits 11 to XLEN-1:	swap offset
783  */
784 #define __SWP_TYPE_SHIFT	7
785 #define __SWP_TYPE_BITS		5
786 #define __SWP_TYPE_MASK		((1UL << __SWP_TYPE_BITS) - 1)
787 #define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
788 
789 #define MAX_SWAPFILES_CHECK()	\
790 	BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
791 
792 #define __swp_type(x)	(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
793 #define __swp_offset(x)	((x).val >> __SWP_OFFSET_SHIFT)
794 #define __swp_entry(type, offset) ((swp_entry_t) \
795 	{ (((type) & __SWP_TYPE_MASK) << __SWP_TYPE_SHIFT) | \
796 	  ((offset) << __SWP_OFFSET_SHIFT) })
797 
798 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
799 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
800 
801 static inline int pte_swp_exclusive(pte_t pte)
802 {
803 	return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
804 }
805 
806 static inline pte_t pte_swp_mkexclusive(pte_t pte)
807 {
808 	return __pte(pte_val(pte) | _PAGE_SWP_EXCLUSIVE);
809 }
810 
811 static inline pte_t pte_swp_clear_exclusive(pte_t pte)
812 {
813 	return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE);
814 }
815 
816 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
817 #define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
818 #define __swp_entry_to_pmd(swp) __pmd((swp).val)
819 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
820 
821 /*
822  * In the RV64 Linux scheme, we give the user half of the virtual-address space
823  * and give the kernel the other (upper) half.
824  */
825 #ifdef CONFIG_64BIT
826 #define KERN_VIRT_START	(-(BIT(VA_BITS)) + TASK_SIZE)
827 #else
828 #define KERN_VIRT_START	FIXADDR_START
829 #endif
830 
831 /*
832  * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32.
833  * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
834  * Task size is:
835  * -     0x9fc00000 (~2.5GB) for RV32.
836  * -   0x4000000000 ( 256GB) for RV64 using SV39 mmu
837  * - 0x800000000000 ( 128TB) for RV64 using SV48 mmu
838  *
839  * Note that PGDIR_SIZE must evenly divide TASK_SIZE since "RISC-V
840  * Instruction Set Manual Volume II: Privileged Architecture" states that
841  * "load and store effective addresses, which are 64bits, must have bits
842  * 63–48 all equal to bit 47, or else a page-fault exception will occur."
843  */
844 #ifdef CONFIG_64BIT
845 #define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
846 #define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
847 
848 #ifdef CONFIG_COMPAT
849 #define TASK_SIZE_32	(_AC(0x80000000, UL) - PAGE_SIZE)
850 #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
851 			 TASK_SIZE_32 : TASK_SIZE_64)
852 #else
853 #define TASK_SIZE	TASK_SIZE_64
854 #endif
855 
856 #else
857 #define TASK_SIZE	FIXADDR_START
858 #define TASK_SIZE_MIN	TASK_SIZE
859 #endif
860 
861 #else /* CONFIG_MMU */
862 
863 #define PAGE_SHARED		__pgprot(0)
864 #define PAGE_KERNEL		__pgprot(0)
865 #define swapper_pg_dir		NULL
866 #define TASK_SIZE		0xffffffffUL
867 #define VMALLOC_START		0
868 #define VMALLOC_END		TASK_SIZE
869 
870 #endif /* !CONFIG_MMU */
871 
872 extern char _start[];
873 extern void *_dtb_early_va;
874 extern uintptr_t _dtb_early_pa;
875 #if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_MMU)
876 #define dtb_early_va	(*(void **)XIP_FIXUP(&_dtb_early_va))
877 #define dtb_early_pa	(*(uintptr_t *)XIP_FIXUP(&_dtb_early_pa))
878 #else
879 #define dtb_early_va	_dtb_early_va
880 #define dtb_early_pa	_dtb_early_pa
881 #endif /* CONFIG_XIP_KERNEL */
882 extern u64 satp_mode;
883 extern bool pgtable_l4_enabled;
884 
885 void paging_init(void);
886 void misc_mem_init(void);
887 
888 /*
889  * ZERO_PAGE is a global shared page that is always zero,
890  * used for zero-mapped memory areas, etc.
891  */
892 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
893 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
894 
895 #endif /* !__ASSEMBLY__ */
896 
897 #endif /* _ASM_RISCV_PGTABLE_H */
898