xref: /openbmc/linux/arch/riscv/include/asm/pgtable.h (revision fbb6b31a)
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 #ifdef CONFIG_64BIT
112 #include <asm/pgtable-64.h>
113 #else
114 #include <asm/pgtable-32.h>
115 #endif /* CONFIG_64BIT */
116 
117 #ifdef CONFIG_XIP_KERNEL
118 #define XIP_FIXUP(addr) ({							\
119 	uintptr_t __a = (uintptr_t)(addr);					\
120 	(__a >= CONFIG_XIP_PHYS_ADDR && \
121 	 __a < CONFIG_XIP_PHYS_ADDR + XIP_OFFSET * 2) ?	\
122 		__a - CONFIG_XIP_PHYS_ADDR + CONFIG_PHYS_RAM_BASE - XIP_OFFSET :\
123 		__a;								\
124 	})
125 #else
126 #define XIP_FIXUP(addr)		(addr)
127 #endif /* CONFIG_XIP_KERNEL */
128 
129 struct pt_alloc_ops {
130 	pte_t *(*get_pte_virt)(phys_addr_t pa);
131 	phys_addr_t (*alloc_pte)(uintptr_t va);
132 #ifndef __PAGETABLE_PMD_FOLDED
133 	pmd_t *(*get_pmd_virt)(phys_addr_t pa);
134 	phys_addr_t (*alloc_pmd)(uintptr_t va);
135 	pud_t *(*get_pud_virt)(phys_addr_t pa);
136 	phys_addr_t (*alloc_pud)(uintptr_t va);
137 	p4d_t *(*get_p4d_virt)(phys_addr_t pa);
138 	phys_addr_t (*alloc_p4d)(uintptr_t va);
139 #endif
140 };
141 
142 extern struct pt_alloc_ops pt_ops __initdata;
143 
144 #ifdef CONFIG_MMU
145 /* Number of PGD entries that a user-mode program can use */
146 #define USER_PTRS_PER_PGD   (TASK_SIZE / PGDIR_SIZE)
147 
148 /* Page protection bits */
149 #define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_USER)
150 
151 #define PAGE_NONE		__pgprot(_PAGE_PROT_NONE | _PAGE_READ)
152 #define PAGE_READ		__pgprot(_PAGE_BASE | _PAGE_READ)
153 #define PAGE_WRITE		__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_WRITE)
154 #define PAGE_EXEC		__pgprot(_PAGE_BASE | _PAGE_EXEC)
155 #define PAGE_READ_EXEC		__pgprot(_PAGE_BASE | _PAGE_READ | _PAGE_EXEC)
156 #define PAGE_WRITE_EXEC		__pgprot(_PAGE_BASE | _PAGE_READ |	\
157 					 _PAGE_EXEC | _PAGE_WRITE)
158 
159 #define PAGE_COPY		PAGE_READ
160 #define PAGE_COPY_EXEC		PAGE_EXEC
161 #define PAGE_COPY_READ_EXEC	PAGE_READ_EXEC
162 #define PAGE_SHARED		PAGE_WRITE
163 #define PAGE_SHARED_EXEC	PAGE_WRITE_EXEC
164 
165 #define _PAGE_KERNEL		(_PAGE_READ \
166 				| _PAGE_WRITE \
167 				| _PAGE_PRESENT \
168 				| _PAGE_ACCESSED \
169 				| _PAGE_DIRTY \
170 				| _PAGE_GLOBAL)
171 
172 #define PAGE_KERNEL		__pgprot(_PAGE_KERNEL)
173 #define PAGE_KERNEL_READ	__pgprot(_PAGE_KERNEL & ~_PAGE_WRITE)
174 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL | _PAGE_EXEC)
175 #define PAGE_KERNEL_READ_EXEC	__pgprot((_PAGE_KERNEL & ~_PAGE_WRITE) \
176 					 | _PAGE_EXEC)
177 
178 #define PAGE_TABLE		__pgprot(_PAGE_TABLE)
179 
180 /*
181  * The RISC-V ISA doesn't yet specify how to query or modify PMAs, so we can't
182  * change the properties of memory regions.
183  */
184 #define _PAGE_IOREMAP _PAGE_KERNEL
185 
186 extern pgd_t swapper_pg_dir[];
187 
188 /* MAP_PRIVATE permissions: xwr (copy-on-write) */
189 #define __P000	PAGE_NONE
190 #define __P001	PAGE_READ
191 #define __P010	PAGE_COPY
192 #define __P011	PAGE_COPY
193 #define __P100	PAGE_EXEC
194 #define __P101	PAGE_READ_EXEC
195 #define __P110	PAGE_COPY_EXEC
196 #define __P111	PAGE_COPY_READ_EXEC
197 
198 /* MAP_SHARED permissions: xwr */
199 #define __S000	PAGE_NONE
200 #define __S001	PAGE_READ
201 #define __S010	PAGE_SHARED
202 #define __S011	PAGE_SHARED
203 #define __S100	PAGE_EXEC
204 #define __S101	PAGE_READ_EXEC
205 #define __S110	PAGE_SHARED_EXEC
206 #define __S111	PAGE_SHARED_EXEC
207 
208 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
209 static inline int pmd_present(pmd_t pmd)
210 {
211 	/*
212 	 * Checking for _PAGE_LEAF is needed too because:
213 	 * When splitting a THP, split_huge_page() will temporarily clear
214 	 * the present bit, in this situation, pmd_present() and
215 	 * pmd_trans_huge() still needs to return true.
216 	 */
217 	return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE | _PAGE_LEAF));
218 }
219 #else
220 static inline int pmd_present(pmd_t pmd)
221 {
222 	return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
223 }
224 #endif
225 
226 static inline int pmd_none(pmd_t pmd)
227 {
228 	return (pmd_val(pmd) == 0);
229 }
230 
231 static inline int pmd_bad(pmd_t pmd)
232 {
233 	return !pmd_present(pmd) || (pmd_val(pmd) & _PAGE_LEAF);
234 }
235 
236 #define pmd_leaf	pmd_leaf
237 static inline int pmd_leaf(pmd_t pmd)
238 {
239 	return pmd_present(pmd) && (pmd_val(pmd) & _PAGE_LEAF);
240 }
241 
242 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
243 {
244 	*pmdp = pmd;
245 }
246 
247 static inline void pmd_clear(pmd_t *pmdp)
248 {
249 	set_pmd(pmdp, __pmd(0));
250 }
251 
252 static inline pgd_t pfn_pgd(unsigned long pfn, pgprot_t prot)
253 {
254 	return __pgd((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot));
255 }
256 
257 static inline unsigned long _pgd_pfn(pgd_t pgd)
258 {
259 	return pgd_val(pgd) >> _PAGE_PFN_SHIFT;
260 }
261 
262 static inline struct page *pmd_page(pmd_t pmd)
263 {
264 	return pfn_to_page(pmd_val(pmd) >> _PAGE_PFN_SHIFT);
265 }
266 
267 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
268 {
269 	return (unsigned long)pfn_to_virt(pmd_val(pmd) >> _PAGE_PFN_SHIFT);
270 }
271 
272 static inline pte_t pmd_pte(pmd_t pmd)
273 {
274 	return __pte(pmd_val(pmd));
275 }
276 
277 static inline pte_t pud_pte(pud_t pud)
278 {
279 	return __pte(pud_val(pud));
280 }
281 
282 /* Yields the page frame number (PFN) of a page table entry */
283 static inline unsigned long pte_pfn(pte_t pte)
284 {
285 	return (pte_val(pte) >> _PAGE_PFN_SHIFT);
286 }
287 
288 #define pte_page(x)     pfn_to_page(pte_pfn(x))
289 
290 /* Constructs a page table entry */
291 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot)
292 {
293 	return __pte((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot));
294 }
295 
296 #define mk_pte(page, prot)       pfn_pte(page_to_pfn(page), prot)
297 
298 static inline int pte_present(pte_t pte)
299 {
300 	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
301 }
302 
303 static inline int pte_none(pte_t pte)
304 {
305 	return (pte_val(pte) == 0);
306 }
307 
308 static inline int pte_write(pte_t pte)
309 {
310 	return pte_val(pte) & _PAGE_WRITE;
311 }
312 
313 static inline int pte_exec(pte_t pte)
314 {
315 	return pte_val(pte) & _PAGE_EXEC;
316 }
317 
318 static inline int pte_huge(pte_t pte)
319 {
320 	return pte_present(pte) && (pte_val(pte) & _PAGE_LEAF);
321 }
322 
323 static inline int pte_dirty(pte_t pte)
324 {
325 	return pte_val(pte) & _PAGE_DIRTY;
326 }
327 
328 static inline int pte_young(pte_t pte)
329 {
330 	return pte_val(pte) & _PAGE_ACCESSED;
331 }
332 
333 static inline int pte_special(pte_t pte)
334 {
335 	return pte_val(pte) & _PAGE_SPECIAL;
336 }
337 
338 /* static inline pte_t pte_rdprotect(pte_t pte) */
339 
340 static inline pte_t pte_wrprotect(pte_t pte)
341 {
342 	return __pte(pte_val(pte) & ~(_PAGE_WRITE));
343 }
344 
345 /* static inline pte_t pte_mkread(pte_t pte) */
346 
347 static inline pte_t pte_mkwrite(pte_t pte)
348 {
349 	return __pte(pte_val(pte) | _PAGE_WRITE);
350 }
351 
352 /* static inline pte_t pte_mkexec(pte_t pte) */
353 
354 static inline pte_t pte_mkdirty(pte_t pte)
355 {
356 	return __pte(pte_val(pte) | _PAGE_DIRTY);
357 }
358 
359 static inline pte_t pte_mkclean(pte_t pte)
360 {
361 	return __pte(pte_val(pte) & ~(_PAGE_DIRTY));
362 }
363 
364 static inline pte_t pte_mkyoung(pte_t pte)
365 {
366 	return __pte(pte_val(pte) | _PAGE_ACCESSED);
367 }
368 
369 static inline pte_t pte_mkold(pte_t pte)
370 {
371 	return __pte(pte_val(pte) & ~(_PAGE_ACCESSED));
372 }
373 
374 static inline pte_t pte_mkspecial(pte_t pte)
375 {
376 	return __pte(pte_val(pte) | _PAGE_SPECIAL);
377 }
378 
379 static inline pte_t pte_mkhuge(pte_t pte)
380 {
381 	return pte;
382 }
383 
384 #ifdef CONFIG_NUMA_BALANCING
385 /*
386  * See the comment in include/asm-generic/pgtable.h
387  */
388 static inline int pte_protnone(pte_t pte)
389 {
390 	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE)) == _PAGE_PROT_NONE;
391 }
392 
393 static inline int pmd_protnone(pmd_t pmd)
394 {
395 	return pte_protnone(pmd_pte(pmd));
396 }
397 #endif
398 
399 /* Modify page protection bits */
400 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
401 {
402 	return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
403 }
404 
405 #define pgd_ERROR(e) \
406 	pr_err("%s:%d: bad pgd " PTE_FMT ".\n", __FILE__, __LINE__, pgd_val(e))
407 
408 
409 /* Commit new configuration to MMU hardware */
410 static inline void update_mmu_cache(struct vm_area_struct *vma,
411 	unsigned long address, pte_t *ptep)
412 {
413 	/*
414 	 * The kernel assumes that TLBs don't cache invalid entries, but
415 	 * in RISC-V, SFENCE.VMA specifies an ordering constraint, not a
416 	 * cache flush; it is necessary even after writing invalid entries.
417 	 * Relying on flush_tlb_fix_spurious_fault would suffice, but
418 	 * the extra traps reduce performance.  So, eagerly SFENCE.VMA.
419 	 */
420 	local_flush_tlb_page(address);
421 }
422 
423 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
424 		unsigned long address, pmd_t *pmdp)
425 {
426 	pte_t *ptep = (pte_t *)pmdp;
427 
428 	update_mmu_cache(vma, address, ptep);
429 }
430 
431 #define __HAVE_ARCH_PTE_SAME
432 static inline int pte_same(pte_t pte_a, pte_t pte_b)
433 {
434 	return pte_val(pte_a) == pte_val(pte_b);
435 }
436 
437 /*
438  * Certain architectures need to do special things when PTEs within
439  * a page table are directly modified.  Thus, the following hook is
440  * made available.
441  */
442 static inline void set_pte(pte_t *ptep, pte_t pteval)
443 {
444 	*ptep = pteval;
445 }
446 
447 void flush_icache_pte(pte_t pte);
448 
449 static inline void set_pte_at(struct mm_struct *mm,
450 	unsigned long addr, pte_t *ptep, pte_t pteval)
451 {
452 	if (pte_present(pteval) && pte_exec(pteval))
453 		flush_icache_pte(pteval);
454 
455 	set_pte(ptep, pteval);
456 }
457 
458 static inline void pte_clear(struct mm_struct *mm,
459 	unsigned long addr, pte_t *ptep)
460 {
461 	set_pte_at(mm, addr, ptep, __pte(0));
462 }
463 
464 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
465 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
466 					unsigned long address, pte_t *ptep,
467 					pte_t entry, int dirty)
468 {
469 	if (!pte_same(*ptep, entry))
470 		set_pte_at(vma->vm_mm, address, ptep, entry);
471 	/*
472 	 * update_mmu_cache will unconditionally execute, handling both
473 	 * the case that the PTE changed and the spurious fault case.
474 	 */
475 	return true;
476 }
477 
478 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
479 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
480 				       unsigned long address, pte_t *ptep)
481 {
482 	return __pte(atomic_long_xchg((atomic_long_t *)ptep, 0));
483 }
484 
485 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
486 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
487 					    unsigned long address,
488 					    pte_t *ptep)
489 {
490 	if (!pte_young(*ptep))
491 		return 0;
492 	return test_and_clear_bit(_PAGE_ACCESSED_OFFSET, &pte_val(*ptep));
493 }
494 
495 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
496 static inline void ptep_set_wrprotect(struct mm_struct *mm,
497 				      unsigned long address, pte_t *ptep)
498 {
499 	atomic_long_and(~(unsigned long)_PAGE_WRITE, (atomic_long_t *)ptep);
500 }
501 
502 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
503 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
504 					 unsigned long address, pte_t *ptep)
505 {
506 	/*
507 	 * This comment is borrowed from x86, but applies equally to RISC-V:
508 	 *
509 	 * Clearing the accessed bit without a TLB flush
510 	 * doesn't cause data corruption. [ It could cause incorrect
511 	 * page aging and the (mistaken) reclaim of hot pages, but the
512 	 * chance of that should be relatively low. ]
513 	 *
514 	 * So as a performance optimization don't flush the TLB when
515 	 * clearing the accessed bit, it will eventually be flushed by
516 	 * a context switch or a VM operation anyway. [ In the rare
517 	 * event of it not getting flushed for a long time the delay
518 	 * shouldn't really matter because there's no real memory
519 	 * pressure for swapout to react to. ]
520 	 */
521 	return ptep_test_and_clear_young(vma, address, ptep);
522 }
523 
524 /*
525  * THP functions
526  */
527 static inline pmd_t pte_pmd(pte_t pte)
528 {
529 	return __pmd(pte_val(pte));
530 }
531 
532 static inline pmd_t pmd_mkhuge(pmd_t pmd)
533 {
534 	return pmd;
535 }
536 
537 static inline pmd_t pmd_mkinvalid(pmd_t pmd)
538 {
539 	return __pmd(pmd_val(pmd) & ~(_PAGE_PRESENT|_PAGE_PROT_NONE));
540 }
541 
542 #define __pmd_to_phys(pmd)  (pmd_val(pmd) >> _PAGE_PFN_SHIFT << PAGE_SHIFT)
543 
544 static inline unsigned long pmd_pfn(pmd_t pmd)
545 {
546 	return ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT);
547 }
548 
549 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
550 {
551 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
552 }
553 
554 #define pmd_write pmd_write
555 static inline int pmd_write(pmd_t pmd)
556 {
557 	return pte_write(pmd_pte(pmd));
558 }
559 
560 static inline int pmd_dirty(pmd_t pmd)
561 {
562 	return pte_dirty(pmd_pte(pmd));
563 }
564 
565 static inline int pmd_young(pmd_t pmd)
566 {
567 	return pte_young(pmd_pte(pmd));
568 }
569 
570 static inline pmd_t pmd_mkold(pmd_t pmd)
571 {
572 	return pte_pmd(pte_mkold(pmd_pte(pmd)));
573 }
574 
575 static inline pmd_t pmd_mkyoung(pmd_t pmd)
576 {
577 	return pte_pmd(pte_mkyoung(pmd_pte(pmd)));
578 }
579 
580 static inline pmd_t pmd_mkwrite(pmd_t pmd)
581 {
582 	return pte_pmd(pte_mkwrite(pmd_pte(pmd)));
583 }
584 
585 static inline pmd_t pmd_wrprotect(pmd_t pmd)
586 {
587 	return pte_pmd(pte_wrprotect(pmd_pte(pmd)));
588 }
589 
590 static inline pmd_t pmd_mkclean(pmd_t pmd)
591 {
592 	return pte_pmd(pte_mkclean(pmd_pte(pmd)));
593 }
594 
595 static inline pmd_t pmd_mkdirty(pmd_t pmd)
596 {
597 	return pte_pmd(pte_mkdirty(pmd_pte(pmd)));
598 }
599 
600 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
601 				pmd_t *pmdp, pmd_t pmd)
602 {
603 	return set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd));
604 }
605 
606 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
607 				pud_t *pudp, pud_t pud)
608 {
609 	return set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud));
610 }
611 
612 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
613 static inline int pmd_trans_huge(pmd_t pmd)
614 {
615 	return pmd_leaf(pmd);
616 }
617 
618 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
619 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
620 					unsigned long address, pmd_t *pmdp,
621 					pmd_t entry, int dirty)
622 {
623 	return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
624 }
625 
626 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
627 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
628 					unsigned long address, pmd_t *pmdp)
629 {
630 	return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
631 }
632 
633 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
634 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
635 					unsigned long address, pmd_t *pmdp)
636 {
637 	return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
638 }
639 
640 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
641 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
642 					unsigned long address, pmd_t *pmdp)
643 {
644 	ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
645 }
646 
647 #define pmdp_establish pmdp_establish
648 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
649 				unsigned long address, pmd_t *pmdp, pmd_t pmd)
650 {
651 	return __pmd(atomic_long_xchg((atomic_long_t *)pmdp, pmd_val(pmd)));
652 }
653 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
654 
655 /*
656  * Encode and decode a swap entry
657  *
658  * Format of swap PTE:
659  *	bit            0:	_PAGE_PRESENT (zero)
660  *	bit       1 to 3:       _PAGE_LEAF (zero)
661  *	bit            5:	_PAGE_PROT_NONE (zero)
662  *	bits      6 to 10:	swap type
663  *	bits 10 to XLEN-1:	swap offset
664  */
665 #define __SWP_TYPE_SHIFT	6
666 #define __SWP_TYPE_BITS		5
667 #define __SWP_TYPE_MASK		((1UL << __SWP_TYPE_BITS) - 1)
668 #define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
669 
670 #define MAX_SWAPFILES_CHECK()	\
671 	BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
672 
673 #define __swp_type(x)	(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
674 #define __swp_offset(x)	((x).val >> __SWP_OFFSET_SHIFT)
675 #define __swp_entry(type, offset) ((swp_entry_t) \
676 	{ ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
677 
678 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
679 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
680 
681 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
682 #define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
683 #define __swp_entry_to_pmd(swp) __pmd((swp).val)
684 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
685 
686 /*
687  * In the RV64 Linux scheme, we give the user half of the virtual-address space
688  * and give the kernel the other (upper) half.
689  */
690 #ifdef CONFIG_64BIT
691 #define KERN_VIRT_START	(-(BIT(VA_BITS)) + TASK_SIZE)
692 #else
693 #define KERN_VIRT_START	FIXADDR_START
694 #endif
695 
696 /*
697  * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32.
698  * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
699  * Task size is:
700  * -     0x9fc00000 (~2.5GB) for RV32.
701  * -   0x4000000000 ( 256GB) for RV64 using SV39 mmu
702  * - 0x800000000000 ( 128TB) for RV64 using SV48 mmu
703  *
704  * Note that PGDIR_SIZE must evenly divide TASK_SIZE since "RISC-V
705  * Instruction Set Manual Volume II: Privileged Architecture" states that
706  * "load and store effective addresses, which are 64bits, must have bits
707  * 63–48 all equal to bit 47, or else a page-fault exception will occur."
708  */
709 #ifdef CONFIG_64BIT
710 #define TASK_SIZE      (PGDIR_SIZE * PTRS_PER_PGD / 2)
711 #define TASK_SIZE_MIN  (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
712 #else
713 #define TASK_SIZE	FIXADDR_START
714 #define TASK_SIZE_MIN	TASK_SIZE
715 #endif
716 
717 #else /* CONFIG_MMU */
718 
719 #define PAGE_SHARED		__pgprot(0)
720 #define PAGE_KERNEL		__pgprot(0)
721 #define swapper_pg_dir		NULL
722 #define TASK_SIZE		0xffffffffUL
723 #define VMALLOC_START		0
724 #define VMALLOC_END		TASK_SIZE
725 
726 #endif /* !CONFIG_MMU */
727 
728 #define kern_addr_valid(addr)   (1) /* FIXME */
729 
730 extern char _start[];
731 extern void *_dtb_early_va;
732 extern uintptr_t _dtb_early_pa;
733 #if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_MMU)
734 #define dtb_early_va	(*(void **)XIP_FIXUP(&_dtb_early_va))
735 #define dtb_early_pa	(*(uintptr_t *)XIP_FIXUP(&_dtb_early_pa))
736 #else
737 #define dtb_early_va	_dtb_early_va
738 #define dtb_early_pa	_dtb_early_pa
739 #endif /* CONFIG_XIP_KERNEL */
740 extern u64 satp_mode;
741 extern bool pgtable_l4_enabled;
742 
743 void paging_init(void);
744 void misc_mem_init(void);
745 
746 /*
747  * ZERO_PAGE is a global shared page that is always zero,
748  * used for zero-mapped memory areas, etc.
749  */
750 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
751 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
752 
753 #endif /* !__ASSEMBLY__ */
754 
755 #endif /* _ASM_RISCV_PGTABLE_H */
756