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9#include <linux/cache.h>
10#include <linux/export.h>
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/init.h>
14#include <linux/ioport.h>
15#include <linux/kexec.h>
16#include <linux/libfdt.h>
17#include <linux/mman.h>
18#include <linux/nodemask.h>
19#include <linux/memblock.h>
20#include <linux/memory.h>
21#include <linux/fs.h>
22#include <linux/io.h>
23#include <linux/mm.h>
24#include <linux/vmalloc.h>
25
26#include <asm/barrier.h>
27#include <asm/cputype.h>
28#include <asm/fixmap.h>
29#include <asm/kasan.h>
30#include <asm/kernel-pgtable.h>
31#include <asm/sections.h>
32#include <asm/setup.h>
33#include <linux/sizes.h>
34#include <asm/tlb.h>
35#include <asm/mmu_context.h>
36#include <asm/ptdump.h>
37#include <asm/tlbflush.h>
38
39#define NO_BLOCK_MAPPINGS BIT(0)
40#define NO_CONT_MAPPINGS BIT(1)
41
42u64 idmap_t0sz = TCR_T0SZ(VA_BITS);
43u64 idmap_ptrs_per_pgd = PTRS_PER_PGD;
44
45u64 __section(".mmuoff.data.write") vabits_actual;
46EXPORT_SYMBOL(vabits_actual);
47
48u64 kimage_voffset __ro_after_init;
49EXPORT_SYMBOL(kimage_voffset);
50
51
52
53
54
55unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
56EXPORT_SYMBOL(empty_zero_page);
57
58static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;
59static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused;
60static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused;
61
62static DEFINE_SPINLOCK(swapper_pgdir_lock);
63
64void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd)
65{
66 pgd_t *fixmap_pgdp;
67
68 spin_lock(&swapper_pgdir_lock);
69 fixmap_pgdp = pgd_set_fixmap(__pa_symbol(pgdp));
70 WRITE_ONCE(*fixmap_pgdp, pgd);
71
72
73
74
75
76 pgd_clear_fixmap();
77 spin_unlock(&swapper_pgdir_lock);
78}
79
80pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
81 unsigned long size, pgprot_t vma_prot)
82{
83 if (!pfn_valid(pfn))
84 return pgprot_noncached(vma_prot);
85 else if (file->f_flags & O_SYNC)
86 return pgprot_writecombine(vma_prot);
87 return vma_prot;
88}
89EXPORT_SYMBOL(phys_mem_access_prot);
90
91static phys_addr_t __init early_pgtable_alloc(int shift)
92{
93 phys_addr_t phys;
94 void *ptr;
95
96 phys = memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
97 if (!phys)
98 panic("Failed to allocate page table page\n");
99
100
101
102
103
104
105 ptr = pte_set_fixmap(phys);
106
107 memset(ptr, 0, PAGE_SIZE);
108
109
110
111
112
113 pte_clear_fixmap();
114
115 return phys;
116}
117
118static bool pgattr_change_is_safe(u64 old, u64 new)
119{
120
121
122
123
124 static const pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE | PTE_NG;
125
126
127 if (old == 0 || new == 0)
128 return true;
129
130
131 if ((old | new) & PTE_CONT)
132 return false;
133
134
135 if (old & ~new & PTE_NG)
136 return false;
137
138 return ((old ^ new) & ~mask) == 0;
139}
140
141static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end,
142 phys_addr_t phys, pgprot_t prot)
143{
144 pte_t *ptep;
145
146 ptep = pte_set_fixmap_offset(pmdp, addr);
147 do {
148 pte_t old_pte = READ_ONCE(*ptep);
149
150 set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot));
151
152
153
154
155
156 BUG_ON(!pgattr_change_is_safe(pte_val(old_pte),
157 READ_ONCE(pte_val(*ptep))));
158
159 phys += PAGE_SIZE;
160 } while (ptep++, addr += PAGE_SIZE, addr != end);
161
162 pte_clear_fixmap();
163}
164
165static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr,
166 unsigned long end, phys_addr_t phys,
167 pgprot_t prot,
168 phys_addr_t (*pgtable_alloc)(int),
169 int flags)
170{
171 unsigned long next;
172 pmd_t pmd = READ_ONCE(*pmdp);
173
174 BUG_ON(pmd_sect(pmd));
175 if (pmd_none(pmd)) {
176 phys_addr_t pte_phys;
177 BUG_ON(!pgtable_alloc);
178 pte_phys = pgtable_alloc(PAGE_SHIFT);
179 __pmd_populate(pmdp, pte_phys, PMD_TYPE_TABLE);
180 pmd = READ_ONCE(*pmdp);
181 }
182 BUG_ON(pmd_bad(pmd));
183
184 do {
185 pgprot_t __prot = prot;
186
187 next = pte_cont_addr_end(addr, end);
188
189
190 if ((((addr | next | phys) & ~CONT_PTE_MASK) == 0) &&
191 (flags & NO_CONT_MAPPINGS) == 0)
192 __prot = __pgprot(pgprot_val(prot) | PTE_CONT);
193
194 init_pte(pmdp, addr, next, phys, __prot);
195
196 phys += next - addr;
197 } while (addr = next, addr != end);
198}
199
200static void init_pmd(pud_t *pudp, unsigned long addr, unsigned long end,
201 phys_addr_t phys, pgprot_t prot,
202 phys_addr_t (*pgtable_alloc)(int), int flags)
203{
204 unsigned long next;
205 pmd_t *pmdp;
206
207 pmdp = pmd_set_fixmap_offset(pudp, addr);
208 do {
209 pmd_t old_pmd = READ_ONCE(*pmdp);
210
211 next = pmd_addr_end(addr, end);
212
213
214 if (((addr | next | phys) & ~SECTION_MASK) == 0 &&
215 (flags & NO_BLOCK_MAPPINGS) == 0) {
216 pmd_set_huge(pmdp, phys, prot);
217
218
219
220
221
222 BUG_ON(!pgattr_change_is_safe(pmd_val(old_pmd),
223 READ_ONCE(pmd_val(*pmdp))));
224 } else {
225 alloc_init_cont_pte(pmdp, addr, next, phys, prot,
226 pgtable_alloc, flags);
227
228 BUG_ON(pmd_val(old_pmd) != 0 &&
229 pmd_val(old_pmd) != READ_ONCE(pmd_val(*pmdp)));
230 }
231 phys += next - addr;
232 } while (pmdp++, addr = next, addr != end);
233
234 pmd_clear_fixmap();
235}
236
237static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr,
238 unsigned long end, phys_addr_t phys,
239 pgprot_t prot,
240 phys_addr_t (*pgtable_alloc)(int), int flags)
241{
242 unsigned long next;
243 pud_t pud = READ_ONCE(*pudp);
244
245
246
247
248 BUG_ON(pud_sect(pud));
249 if (pud_none(pud)) {
250 phys_addr_t pmd_phys;
251 BUG_ON(!pgtable_alloc);
252 pmd_phys = pgtable_alloc(PMD_SHIFT);
253 __pud_populate(pudp, pmd_phys, PUD_TYPE_TABLE);
254 pud = READ_ONCE(*pudp);
255 }
256 BUG_ON(pud_bad(pud));
257
258 do {
259 pgprot_t __prot = prot;
260
261 next = pmd_cont_addr_end(addr, end);
262
263
264 if ((((addr | next | phys) & ~CONT_PMD_MASK) == 0) &&
265 (flags & NO_CONT_MAPPINGS) == 0)
266 __prot = __pgprot(pgprot_val(prot) | PTE_CONT);
267
268 init_pmd(pudp, addr, next, phys, __prot, pgtable_alloc, flags);
269
270 phys += next - addr;
271 } while (addr = next, addr != end);
272}
273
274static inline bool use_1G_block(unsigned long addr, unsigned long next,
275 unsigned long phys)
276{
277 if (PAGE_SHIFT != 12)
278 return false;
279
280 if (((addr | next | phys) & ~PUD_MASK) != 0)
281 return false;
282
283 return true;
284}
285
286static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end,
287 phys_addr_t phys, pgprot_t prot,
288 phys_addr_t (*pgtable_alloc)(int),
289 int flags)
290{
291 unsigned long next;
292 pud_t *pudp;
293 pgd_t pgd = READ_ONCE(*pgdp);
294
295 if (pgd_none(pgd)) {
296 phys_addr_t pud_phys;
297 BUG_ON(!pgtable_alloc);
298 pud_phys = pgtable_alloc(PUD_SHIFT);
299 __pgd_populate(pgdp, pud_phys, PUD_TYPE_TABLE);
300 pgd = READ_ONCE(*pgdp);
301 }
302 BUG_ON(pgd_bad(pgd));
303
304 pudp = pud_set_fixmap_offset(pgdp, addr);
305 do {
306 pud_t old_pud = READ_ONCE(*pudp);
307
308 next = pud_addr_end(addr, end);
309
310
311
312
313 if (use_1G_block(addr, next, phys) &&
314 (flags & NO_BLOCK_MAPPINGS) == 0) {
315 pud_set_huge(pudp, phys, prot);
316
317
318
319
320
321 BUG_ON(!pgattr_change_is_safe(pud_val(old_pud),
322 READ_ONCE(pud_val(*pudp))));
323 } else {
324 alloc_init_cont_pmd(pudp, addr, next, phys, prot,
325 pgtable_alloc, flags);
326
327 BUG_ON(pud_val(old_pud) != 0 &&
328 pud_val(old_pud) != READ_ONCE(pud_val(*pudp)));
329 }
330 phys += next - addr;
331 } while (pudp++, addr = next, addr != end);
332
333 pud_clear_fixmap();
334}
335
336static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys,
337 unsigned long virt, phys_addr_t size,
338 pgprot_t prot,
339 phys_addr_t (*pgtable_alloc)(int),
340 int flags)
341{
342 unsigned long addr, end, next;
343 pgd_t *pgdp = pgd_offset_raw(pgdir, virt);
344
345
346
347
348
349 if (WARN_ON((phys ^ virt) & ~PAGE_MASK))
350 return;
351
352 phys &= PAGE_MASK;
353 addr = virt & PAGE_MASK;
354 end = PAGE_ALIGN(virt + size);
355
356 do {
357 next = pgd_addr_end(addr, end);
358 alloc_init_pud(pgdp, addr, next, phys, prot, pgtable_alloc,
359 flags);
360 phys += next - addr;
361 } while (pgdp++, addr = next, addr != end);
362}
363
364static phys_addr_t __pgd_pgtable_alloc(int shift)
365{
366 void *ptr = (void *)__get_free_page(GFP_PGTABLE_KERNEL);
367 BUG_ON(!ptr);
368
369
370 dsb(ishst);
371 return __pa(ptr);
372}
373
374static phys_addr_t pgd_pgtable_alloc(int shift)
375{
376 phys_addr_t pa = __pgd_pgtable_alloc(shift);
377
378
379
380
381
382
383
384
385
386 if (shift == PAGE_SHIFT)
387 BUG_ON(!pgtable_pte_page_ctor(phys_to_page(pa)));
388 else if (shift == PMD_SHIFT)
389 BUG_ON(!pgtable_pmd_page_ctor(phys_to_page(pa)));
390
391 return pa;
392}
393
394
395
396
397
398
399static void __init create_mapping_noalloc(phys_addr_t phys, unsigned long virt,
400 phys_addr_t size, pgprot_t prot)
401{
402 if ((virt >= PAGE_END) && (virt < VMALLOC_START)) {
403 pr_warn("BUG: not creating mapping for %pa at 0x%016lx - outside kernel range\n",
404 &phys, virt);
405 return;
406 }
407 __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL,
408 NO_CONT_MAPPINGS);
409}
410
411void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
412 unsigned long virt, phys_addr_t size,
413 pgprot_t prot, bool page_mappings_only)
414{
415 int flags = 0;
416
417 BUG_ON(mm == &init_mm);
418
419 if (page_mappings_only)
420 flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
421
422 __create_pgd_mapping(mm->pgd, phys, virt, size, prot,
423 pgd_pgtable_alloc, flags);
424}
425
426static void update_mapping_prot(phys_addr_t phys, unsigned long virt,
427 phys_addr_t size, pgprot_t prot)
428{
429 if ((virt >= PAGE_END) && (virt < VMALLOC_START)) {
430 pr_warn("BUG: not updating mapping for %pa at 0x%016lx - outside kernel range\n",
431 &phys, virt);
432 return;
433 }
434
435 __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL,
436 NO_CONT_MAPPINGS);
437
438
439 flush_tlb_kernel_range(virt, virt + size);
440}
441
442static void __init __map_memblock(pgd_t *pgdp, phys_addr_t start,
443 phys_addr_t end, pgprot_t prot, int flags)
444{
445 __create_pgd_mapping(pgdp, start, __phys_to_virt(start), end - start,
446 prot, early_pgtable_alloc, flags);
447}
448
449void __init mark_linear_text_alias_ro(void)
450{
451
452
453
454 update_mapping_prot(__pa_symbol(_text), (unsigned long)lm_alias(_text),
455 (unsigned long)__init_begin - (unsigned long)_text,
456 PAGE_KERNEL_RO);
457}
458
459static void __init map_mem(pgd_t *pgdp)
460{
461 phys_addr_t kernel_start = __pa_symbol(_text);
462 phys_addr_t kernel_end = __pa_symbol(__init_begin);
463 struct memblock_region *reg;
464 int flags = 0;
465
466 if (rodata_full || debug_pagealloc_enabled())
467 flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
468
469
470
471
472
473
474
475 memblock_mark_nomap(kernel_start, kernel_end - kernel_start);
476#ifdef CONFIG_KEXEC_CORE
477 if (crashk_res.end)
478 memblock_mark_nomap(crashk_res.start,
479 resource_size(&crashk_res));
480#endif
481
482
483 for_each_memblock(memory, reg) {
484 phys_addr_t start = reg->base;
485 phys_addr_t end = start + reg->size;
486
487 if (start >= end)
488 break;
489 if (memblock_is_nomap(reg))
490 continue;
491
492 __map_memblock(pgdp, start, end, PAGE_KERNEL, flags);
493 }
494
495
496
497
498
499
500
501
502
503
504
505 __map_memblock(pgdp, kernel_start, kernel_end,
506 PAGE_KERNEL, NO_CONT_MAPPINGS);
507 memblock_clear_nomap(kernel_start, kernel_end - kernel_start);
508
509#ifdef CONFIG_KEXEC_CORE
510
511
512
513
514
515 if (crashk_res.end) {
516 __map_memblock(pgdp, crashk_res.start, crashk_res.end + 1,
517 PAGE_KERNEL,
518 NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS);
519 memblock_clear_nomap(crashk_res.start,
520 resource_size(&crashk_res));
521 }
522#endif
523}
524
525void mark_rodata_ro(void)
526{
527 unsigned long section_size;
528
529
530
531
532
533 section_size = (unsigned long)__init_begin - (unsigned long)__start_rodata;
534 update_mapping_prot(__pa_symbol(__start_rodata), (unsigned long)__start_rodata,
535 section_size, PAGE_KERNEL_RO);
536
537 debug_checkwx();
538}
539
540static void __init map_kernel_segment(pgd_t *pgdp, void *va_start, void *va_end,
541 pgprot_t prot, struct vm_struct *vma,
542 int flags, unsigned long vm_flags)
543{
544 phys_addr_t pa_start = __pa_symbol(va_start);
545 unsigned long size = va_end - va_start;
546
547 BUG_ON(!PAGE_ALIGNED(pa_start));
548 BUG_ON(!PAGE_ALIGNED(size));
549
550 __create_pgd_mapping(pgdp, pa_start, (unsigned long)va_start, size, prot,
551 early_pgtable_alloc, flags);
552
553 if (!(vm_flags & VM_NO_GUARD))
554 size += PAGE_SIZE;
555
556 vma->addr = va_start;
557 vma->phys_addr = pa_start;
558 vma->size = size;
559 vma->flags = VM_MAP | vm_flags;
560 vma->caller = __builtin_return_address(0);
561
562 vm_area_add_early(vma);
563}
564
565static int __init parse_rodata(char *arg)
566{
567 int ret = strtobool(arg, &rodata_enabled);
568 if (!ret) {
569 rodata_full = false;
570 return 0;
571 }
572
573
574 if (strcmp(arg, "full"))
575 return -EINVAL;
576
577 rodata_enabled = true;
578 rodata_full = true;
579 return 0;
580}
581early_param("rodata", parse_rodata);
582
583#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
584static int __init map_entry_trampoline(void)
585{
586 pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
587 phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start);
588
589
590 pgprot_val(prot) &= ~PTE_NG;
591
592
593 memset(tramp_pg_dir, 0, PGD_SIZE);
594 __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE,
595 prot, __pgd_pgtable_alloc, 0);
596
597
598 __set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot);
599 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
600 extern char __entry_tramp_data_start[];
601
602 __set_fixmap(FIX_ENTRY_TRAMP_DATA,
603 __pa_symbol(__entry_tramp_data_start),
604 PAGE_KERNEL_RO);
605 }
606
607 return 0;
608}
609core_initcall(map_entry_trampoline);
610#endif
611
612
613
614
615static void __init map_kernel(pgd_t *pgdp)
616{
617 static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_inittext,
618 vmlinux_initdata, vmlinux_data;
619
620
621
622
623
624
625 pgprot_t text_prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
626
627
628
629
630
631 map_kernel_segment(pgdp, _text, _etext, text_prot, &vmlinux_text, 0,
632 VM_NO_GUARD);
633 map_kernel_segment(pgdp, __start_rodata, __inittext_begin, PAGE_KERNEL,
634 &vmlinux_rodata, NO_CONT_MAPPINGS, VM_NO_GUARD);
635 map_kernel_segment(pgdp, __inittext_begin, __inittext_end, text_prot,
636 &vmlinux_inittext, 0, VM_NO_GUARD);
637 map_kernel_segment(pgdp, __initdata_begin, __initdata_end, PAGE_KERNEL,
638 &vmlinux_initdata, 0, VM_NO_GUARD);
639 map_kernel_segment(pgdp, _data, _end, PAGE_KERNEL, &vmlinux_data, 0, 0);
640
641 if (!READ_ONCE(pgd_val(*pgd_offset_raw(pgdp, FIXADDR_START)))) {
642
643
644
645
646
647 set_pgd(pgd_offset_raw(pgdp, FIXADDR_START),
648 READ_ONCE(*pgd_offset_k(FIXADDR_START)));
649 } else if (CONFIG_PGTABLE_LEVELS > 3) {
650 pgd_t *bm_pgdp;
651 pud_t *bm_pudp;
652
653
654
655
656
657
658 BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
659 bm_pgdp = pgd_offset_raw(pgdp, FIXADDR_START);
660 bm_pudp = pud_set_fixmap_offset(bm_pgdp, FIXADDR_START);
661 pud_populate(&init_mm, bm_pudp, lm_alias(bm_pmd));
662 pud_clear_fixmap();
663 } else {
664 BUG();
665 }
666
667 kasan_copy_shadow(pgdp);
668}
669
670void __init paging_init(void)
671{
672 pgd_t *pgdp = pgd_set_fixmap(__pa_symbol(swapper_pg_dir));
673
674 map_kernel(pgdp);
675 map_mem(pgdp);
676
677 pgd_clear_fixmap();
678
679 cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
680 init_mm.pgd = swapper_pg_dir;
681
682 memblock_free(__pa_symbol(init_pg_dir),
683 __pa_symbol(init_pg_end) - __pa_symbol(init_pg_dir));
684
685 memblock_allow_resize();
686}
687
688
689
690
691int kern_addr_valid(unsigned long addr)
692{
693 pgd_t *pgdp;
694 pud_t *pudp, pud;
695 pmd_t *pmdp, pmd;
696 pte_t *ptep, pte;
697
698 if ((((long)addr) >> VA_BITS) != -1UL)
699 return 0;
700
701 pgdp = pgd_offset_k(addr);
702 if (pgd_none(READ_ONCE(*pgdp)))
703 return 0;
704
705 pudp = pud_offset(pgdp, addr);
706 pud = READ_ONCE(*pudp);
707 if (pud_none(pud))
708 return 0;
709
710 if (pud_sect(pud))
711 return pfn_valid(pud_pfn(pud));
712
713 pmdp = pmd_offset(pudp, addr);
714 pmd = READ_ONCE(*pmdp);
715 if (pmd_none(pmd))
716 return 0;
717
718 if (pmd_sect(pmd))
719 return pfn_valid(pmd_pfn(pmd));
720
721 ptep = pte_offset_kernel(pmdp, addr);
722 pte = READ_ONCE(*ptep);
723 if (pte_none(pte))
724 return 0;
725
726 return pfn_valid(pte_pfn(pte));
727}
728
729#ifdef CONFIG_MEMORY_HOTPLUG
730static void free_hotplug_page_range(struct page *page, size_t size)
731{
732 WARN_ON(PageReserved(page));
733 free_pages((unsigned long)page_address(page), get_order(size));
734}
735
736static void free_hotplug_pgtable_page(struct page *page)
737{
738 free_hotplug_page_range(page, PAGE_SIZE);
739}
740
741static bool pgtable_range_aligned(unsigned long start, unsigned long end,
742 unsigned long floor, unsigned long ceiling,
743 unsigned long mask)
744{
745 start &= mask;
746 if (start < floor)
747 return false;
748
749 if (ceiling) {
750 ceiling &= mask;
751 if (!ceiling)
752 return false;
753 }
754
755 if (end - 1 > ceiling - 1)
756 return false;
757 return true;
758}
759
760static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr,
761 unsigned long end, bool free_mapped)
762{
763 pte_t *ptep, pte;
764
765 do {
766 ptep = pte_offset_kernel(pmdp, addr);
767 pte = READ_ONCE(*ptep);
768 if (pte_none(pte))
769 continue;
770
771 WARN_ON(!pte_present(pte));
772 pte_clear(&init_mm, addr, ptep);
773 flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
774 if (free_mapped)
775 free_hotplug_page_range(pte_page(pte), PAGE_SIZE);
776 } while (addr += PAGE_SIZE, addr < end);
777}
778
779static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr,
780 unsigned long end, bool free_mapped)
781{
782 unsigned long next;
783 pmd_t *pmdp, pmd;
784
785 do {
786 next = pmd_addr_end(addr, end);
787 pmdp = pmd_offset(pudp, addr);
788 pmd = READ_ONCE(*pmdp);
789 if (pmd_none(pmd))
790 continue;
791
792 WARN_ON(!pmd_present(pmd));
793 if (pmd_sect(pmd)) {
794 pmd_clear(pmdp);
795
796
797
798
799
800 flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
801 if (free_mapped)
802 free_hotplug_page_range(pmd_page(pmd),
803 PMD_SIZE);
804 continue;
805 }
806 WARN_ON(!pmd_table(pmd));
807 unmap_hotplug_pte_range(pmdp, addr, next, free_mapped);
808 } while (addr = next, addr < end);
809}
810
811static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr,
812 unsigned long end, bool free_mapped)
813{
814 unsigned long next;
815 pud_t *pudp, pud;
816
817 do {
818 next = pud_addr_end(addr, end);
819 pudp = pud_offset(p4dp, addr);
820 pud = READ_ONCE(*pudp);
821 if (pud_none(pud))
822 continue;
823
824 WARN_ON(!pud_present(pud));
825 if (pud_sect(pud)) {
826 pud_clear(pudp);
827
828
829
830
831
832 flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
833 if (free_mapped)
834 free_hotplug_page_range(pud_page(pud),
835 PUD_SIZE);
836 continue;
837 }
838 WARN_ON(!pud_table(pud));
839 unmap_hotplug_pmd_range(pudp, addr, next, free_mapped);
840 } while (addr = next, addr < end);
841}
842
843static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr,
844 unsigned long end, bool free_mapped)
845{
846 unsigned long next;
847 p4d_t *p4dp, p4d;
848
849 do {
850 next = p4d_addr_end(addr, end);
851 p4dp = p4d_offset(pgdp, addr);
852 p4d = READ_ONCE(*p4dp);
853 if (p4d_none(p4d))
854 continue;
855
856 WARN_ON(!p4d_present(p4d));
857 unmap_hotplug_pud_range(p4dp, addr, next, free_mapped);
858 } while (addr = next, addr < end);
859}
860
861static void unmap_hotplug_range(unsigned long addr, unsigned long end,
862 bool free_mapped)
863{
864 unsigned long next;
865 pgd_t *pgdp, pgd;
866
867 do {
868 next = pgd_addr_end(addr, end);
869 pgdp = pgd_offset_k(addr);
870 pgd = READ_ONCE(*pgdp);
871 if (pgd_none(pgd))
872 continue;
873
874 WARN_ON(!pgd_present(pgd));
875 unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped);
876 } while (addr = next, addr < end);
877}
878
879static void free_empty_pte_table(pmd_t *pmdp, unsigned long addr,
880 unsigned long end, unsigned long floor,
881 unsigned long ceiling)
882{
883 pte_t *ptep, pte;
884 unsigned long i, start = addr;
885
886 do {
887 ptep = pte_offset_kernel(pmdp, addr);
888 pte = READ_ONCE(*ptep);
889
890
891
892
893
894 WARN_ON(!pte_none(pte));
895 } while (addr += PAGE_SIZE, addr < end);
896
897 if (!pgtable_range_aligned(start, end, floor, ceiling, PMD_MASK))
898 return;
899
900
901
902
903
904
905 ptep = pte_offset_kernel(pmdp, 0UL);
906 for (i = 0; i < PTRS_PER_PTE; i++) {
907 if (!pte_none(READ_ONCE(ptep[i])))
908 return;
909 }
910
911 pmd_clear(pmdp);
912 __flush_tlb_kernel_pgtable(start);
913 free_hotplug_pgtable_page(virt_to_page(ptep));
914}
915
916static void free_empty_pmd_table(pud_t *pudp, unsigned long addr,
917 unsigned long end, unsigned long floor,
918 unsigned long ceiling)
919{
920 pmd_t *pmdp, pmd;
921 unsigned long i, next, start = addr;
922
923 do {
924 next = pmd_addr_end(addr, end);
925 pmdp = pmd_offset(pudp, addr);
926 pmd = READ_ONCE(*pmdp);
927 if (pmd_none(pmd))
928 continue;
929
930 WARN_ON(!pmd_present(pmd) || !pmd_table(pmd) || pmd_sect(pmd));
931 free_empty_pte_table(pmdp, addr, next, floor, ceiling);
932 } while (addr = next, addr < end);
933
934 if (CONFIG_PGTABLE_LEVELS <= 2)
935 return;
936
937 if (!pgtable_range_aligned(start, end, floor, ceiling, PUD_MASK))
938 return;
939
940
941
942
943
944
945 pmdp = pmd_offset(pudp, 0UL);
946 for (i = 0; i < PTRS_PER_PMD; i++) {
947 if (!pmd_none(READ_ONCE(pmdp[i])))
948 return;
949 }
950
951 pud_clear(pudp);
952 __flush_tlb_kernel_pgtable(start);
953 free_hotplug_pgtable_page(virt_to_page(pmdp));
954}
955
956static void free_empty_pud_table(p4d_t *p4dp, unsigned long addr,
957 unsigned long end, unsigned long floor,
958 unsigned long ceiling)
959{
960 pud_t *pudp, pud;
961 unsigned long i, next, start = addr;
962
963 do {
964 next = pud_addr_end(addr, end);
965 pudp = pud_offset(p4dp, addr);
966 pud = READ_ONCE(*pudp);
967 if (pud_none(pud))
968 continue;
969
970 WARN_ON(!pud_present(pud) || !pud_table(pud) || pud_sect(pud));
971 free_empty_pmd_table(pudp, addr, next, floor, ceiling);
972 } while (addr = next, addr < end);
973
974 if (CONFIG_PGTABLE_LEVELS <= 3)
975 return;
976
977 if (!pgtable_range_aligned(start, end, floor, ceiling, PGDIR_MASK))
978 return;
979
980
981
982
983
984
985 pudp = pud_offset(p4dp, 0UL);
986 for (i = 0; i < PTRS_PER_PUD; i++) {
987 if (!pud_none(READ_ONCE(pudp[i])))
988 return;
989 }
990
991 p4d_clear(p4dp);
992 __flush_tlb_kernel_pgtable(start);
993 free_hotplug_pgtable_page(virt_to_page(pudp));
994}
995
996static void free_empty_p4d_table(pgd_t *pgdp, unsigned long addr,
997 unsigned long end, unsigned long floor,
998 unsigned long ceiling)
999{
1000 unsigned long next;
1001 p4d_t *p4dp, p4d;
1002
1003 do {
1004 next = p4d_addr_end(addr, end);
1005 p4dp = p4d_offset(pgdp, addr);
1006 p4d = READ_ONCE(*p4dp);
1007 if (p4d_none(p4d))
1008 continue;
1009
1010 WARN_ON(!p4d_present(p4d));
1011 free_empty_pud_table(p4dp, addr, next, floor, ceiling);
1012 } while (addr = next, addr < end);
1013}
1014
1015static void free_empty_tables(unsigned long addr, unsigned long end,
1016 unsigned long floor, unsigned long ceiling)
1017{
1018 unsigned long next;
1019 pgd_t *pgdp, pgd;
1020
1021 do {
1022 next = pgd_addr_end(addr, end);
1023 pgdp = pgd_offset_k(addr);
1024 pgd = READ_ONCE(*pgdp);
1025 if (pgd_none(pgd))
1026 continue;
1027
1028 WARN_ON(!pgd_present(pgd));
1029 free_empty_p4d_table(pgdp, addr, next, floor, ceiling);
1030 } while (addr = next, addr < end);
1031}
1032#endif
1033
1034#ifdef CONFIG_SPARSEMEM_VMEMMAP
1035#if !ARM64_SWAPPER_USES_SECTION_MAPS
1036int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1037 struct vmem_altmap *altmap)
1038{
1039 return vmemmap_populate_basepages(start, end, node);
1040}
1041#else
1042int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1043 struct vmem_altmap *altmap)
1044{
1045 unsigned long addr = start;
1046 unsigned long next;
1047 pgd_t *pgdp;
1048 pud_t *pudp;
1049 pmd_t *pmdp;
1050
1051 do {
1052 next = pmd_addr_end(addr, end);
1053
1054 pgdp = vmemmap_pgd_populate(addr, node);
1055 if (!pgdp)
1056 return -ENOMEM;
1057
1058 pudp = vmemmap_pud_populate(pgdp, addr, node);
1059 if (!pudp)
1060 return -ENOMEM;
1061
1062 pmdp = pmd_offset(pudp, addr);
1063 if (pmd_none(READ_ONCE(*pmdp))) {
1064 void *p = NULL;
1065
1066 p = vmemmap_alloc_block_buf(PMD_SIZE, node);
1067 if (!p)
1068 return -ENOMEM;
1069
1070 pmd_set_huge(pmdp, __pa(p), __pgprot(PROT_SECT_NORMAL));
1071 } else
1072 vmemmap_verify((pte_t *)pmdp, node, addr, next);
1073 } while (addr = next, addr != end);
1074
1075 return 0;
1076}
1077#endif
1078void vmemmap_free(unsigned long start, unsigned long end,
1079 struct vmem_altmap *altmap)
1080{
1081#ifdef CONFIG_MEMORY_HOTPLUG
1082 WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END));
1083
1084 unmap_hotplug_range(start, end, true);
1085 free_empty_tables(start, end, VMEMMAP_START, VMEMMAP_END);
1086#endif
1087}
1088#endif
1089
1090static inline pud_t * fixmap_pud(unsigned long addr)
1091{
1092 pgd_t *pgdp = pgd_offset_k(addr);
1093 pgd_t pgd = READ_ONCE(*pgdp);
1094
1095 BUG_ON(pgd_none(pgd) || pgd_bad(pgd));
1096
1097 return pud_offset_kimg(pgdp, addr);
1098}
1099
1100static inline pmd_t * fixmap_pmd(unsigned long addr)
1101{
1102 pud_t *pudp = fixmap_pud(addr);
1103 pud_t pud = READ_ONCE(*pudp);
1104
1105 BUG_ON(pud_none(pud) || pud_bad(pud));
1106
1107 return pmd_offset_kimg(pudp, addr);
1108}
1109
1110static inline pte_t * fixmap_pte(unsigned long addr)
1111{
1112 return &bm_pte[pte_index(addr)];
1113}
1114
1115
1116
1117
1118
1119
1120
1121void __init early_fixmap_init(void)
1122{
1123 pgd_t *pgdp, pgd;
1124 pud_t *pudp;
1125 pmd_t *pmdp;
1126 unsigned long addr = FIXADDR_START;
1127
1128 pgdp = pgd_offset_k(addr);
1129 pgd = READ_ONCE(*pgdp);
1130 if (CONFIG_PGTABLE_LEVELS > 3 &&
1131 !(pgd_none(pgd) || pgd_page_paddr(pgd) == __pa_symbol(bm_pud))) {
1132
1133
1134
1135
1136
1137 BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
1138 pudp = pud_offset_kimg(pgdp, addr);
1139 } else {
1140 if (pgd_none(pgd))
1141 __pgd_populate(pgdp, __pa_symbol(bm_pud), PUD_TYPE_TABLE);
1142 pudp = fixmap_pud(addr);
1143 }
1144 if (pud_none(READ_ONCE(*pudp)))
1145 __pud_populate(pudp, __pa_symbol(bm_pmd), PMD_TYPE_TABLE);
1146 pmdp = fixmap_pmd(addr);
1147 __pmd_populate(pmdp, __pa_symbol(bm_pte), PMD_TYPE_TABLE);
1148
1149
1150
1151
1152
1153 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
1154 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
1155
1156 if ((pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)))
1157 || pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_END))) {
1158 WARN_ON(1);
1159 pr_warn("pmdp %p != %p, %p\n",
1160 pmdp, fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)),
1161 fixmap_pmd(fix_to_virt(FIX_BTMAP_END)));
1162 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
1163 fix_to_virt(FIX_BTMAP_BEGIN));
1164 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
1165 fix_to_virt(FIX_BTMAP_END));
1166
1167 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
1168 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
1169 }
1170}
1171
1172
1173
1174
1175
1176void __set_fixmap(enum fixed_addresses idx,
1177 phys_addr_t phys, pgprot_t flags)
1178{
1179 unsigned long addr = __fix_to_virt(idx);
1180 pte_t *ptep;
1181
1182 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
1183
1184 ptep = fixmap_pte(addr);
1185
1186 if (pgprot_val(flags)) {
1187 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags));
1188 } else {
1189 pte_clear(&init_mm, addr, ptep);
1190 flush_tlb_kernel_range(addr, addr+PAGE_SIZE);
1191 }
1192}
1193
1194void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
1195{
1196 const u64 dt_virt_base = __fix_to_virt(FIX_FDT);
1197 int offset;
1198 void *dt_virt;
1199
1200
1201
1202
1203
1204
1205
1206
1207 BUILD_BUG_ON(MIN_FDT_ALIGN < 8);
1208 if (!dt_phys || dt_phys % MIN_FDT_ALIGN)
1209 return NULL;
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221 BUILD_BUG_ON(dt_virt_base % SZ_2M);
1222
1223 BUILD_BUG_ON(__fix_to_virt(FIX_FDT_END) >> SWAPPER_TABLE_SHIFT !=
1224 __fix_to_virt(FIX_BTMAP_BEGIN) >> SWAPPER_TABLE_SHIFT);
1225
1226 offset = dt_phys % SWAPPER_BLOCK_SIZE;
1227 dt_virt = (void *)dt_virt_base + offset;
1228
1229
1230 create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE),
1231 dt_virt_base, SWAPPER_BLOCK_SIZE, prot);
1232
1233 if (fdt_magic(dt_virt) != FDT_MAGIC)
1234 return NULL;
1235
1236 *size = fdt_totalsize(dt_virt);
1237 if (*size > MAX_FDT_SIZE)
1238 return NULL;
1239
1240 if (offset + *size > SWAPPER_BLOCK_SIZE)
1241 create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
1242 round_up(offset + *size, SWAPPER_BLOCK_SIZE), prot);
1243
1244 return dt_virt;
1245}
1246
1247int __init arch_ioremap_p4d_supported(void)
1248{
1249 return 0;
1250}
1251
1252int __init arch_ioremap_pud_supported(void)
1253{
1254
1255
1256
1257
1258 return IS_ENABLED(CONFIG_ARM64_4K_PAGES) &&
1259 !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
1260}
1261
1262int __init arch_ioremap_pmd_supported(void)
1263{
1264
1265 return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
1266}
1267
1268int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot)
1269{
1270 pud_t new_pud = pfn_pud(__phys_to_pfn(phys), mk_pud_sect_prot(prot));
1271
1272
1273 if (!pgattr_change_is_safe(READ_ONCE(pud_val(*pudp)),
1274 pud_val(new_pud)))
1275 return 0;
1276
1277 VM_BUG_ON(phys & ~PUD_MASK);
1278 set_pud(pudp, new_pud);
1279 return 1;
1280}
1281
1282int pmd_set_huge(pmd_t *pmdp, phys_addr_t phys, pgprot_t prot)
1283{
1284 pmd_t new_pmd = pfn_pmd(__phys_to_pfn(phys), mk_pmd_sect_prot(prot));
1285
1286
1287 if (!pgattr_change_is_safe(READ_ONCE(pmd_val(*pmdp)),
1288 pmd_val(new_pmd)))
1289 return 0;
1290
1291 VM_BUG_ON(phys & ~PMD_MASK);
1292 set_pmd(pmdp, new_pmd);
1293 return 1;
1294}
1295
1296int pud_clear_huge(pud_t *pudp)
1297{
1298 if (!pud_sect(READ_ONCE(*pudp)))
1299 return 0;
1300 pud_clear(pudp);
1301 return 1;
1302}
1303
1304int pmd_clear_huge(pmd_t *pmdp)
1305{
1306 if (!pmd_sect(READ_ONCE(*pmdp)))
1307 return 0;
1308 pmd_clear(pmdp);
1309 return 1;
1310}
1311
1312int pmd_free_pte_page(pmd_t *pmdp, unsigned long addr)
1313{
1314 pte_t *table;
1315 pmd_t pmd;
1316
1317 pmd = READ_ONCE(*pmdp);
1318
1319 if (!pmd_table(pmd)) {
1320 VM_WARN_ON(1);
1321 return 1;
1322 }
1323
1324 table = pte_offset_kernel(pmdp, addr);
1325 pmd_clear(pmdp);
1326 __flush_tlb_kernel_pgtable(addr);
1327 pte_free_kernel(NULL, table);
1328 return 1;
1329}
1330
1331int pud_free_pmd_page(pud_t *pudp, unsigned long addr)
1332{
1333 pmd_t *table;
1334 pmd_t *pmdp;
1335 pud_t pud;
1336 unsigned long next, end;
1337
1338 pud = READ_ONCE(*pudp);
1339
1340 if (!pud_table(pud)) {
1341 VM_WARN_ON(1);
1342 return 1;
1343 }
1344
1345 table = pmd_offset(pudp, addr);
1346 pmdp = table;
1347 next = addr;
1348 end = addr + PUD_SIZE;
1349 do {
1350 pmd_free_pte_page(pmdp, next);
1351 } while (pmdp++, next += PMD_SIZE, next != end);
1352
1353 pud_clear(pudp);
1354 __flush_tlb_kernel_pgtable(addr);
1355 pmd_free(NULL, table);
1356 return 1;
1357}
1358
1359int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
1360{
1361 return 0;
1362}
1363
1364#ifdef CONFIG_MEMORY_HOTPLUG
1365static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
1366{
1367 unsigned long end = start + size;
1368
1369 WARN_ON(pgdir != init_mm.pgd);
1370 WARN_ON((start < PAGE_OFFSET) || (end > PAGE_END));
1371
1372 unmap_hotplug_range(start, end, false);
1373 free_empty_tables(start, end, PAGE_OFFSET, PAGE_END);
1374}
1375
1376int arch_add_memory(int nid, u64 start, u64 size,
1377 struct mhp_params *params)
1378{
1379 int ret, flags = 0;
1380
1381 if (rodata_full || debug_pagealloc_enabled())
1382 flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
1383
1384 __create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start),
1385 size, params->pgprot, __pgd_pgtable_alloc,
1386 flags);
1387
1388 memblock_clear_nomap(start, size);
1389
1390 ret = __add_pages(nid, start >> PAGE_SHIFT, size >> PAGE_SHIFT,
1391 params);
1392 if (ret)
1393 __remove_pgd_mapping(swapper_pg_dir,
1394 __phys_to_virt(start), size);
1395 return ret;
1396}
1397
1398void arch_remove_memory(int nid, u64 start, u64 size,
1399 struct vmem_altmap *altmap)
1400{
1401 unsigned long start_pfn = start >> PAGE_SHIFT;
1402 unsigned long nr_pages = size >> PAGE_SHIFT;
1403
1404 __remove_pages(start_pfn, nr_pages, altmap);
1405 __remove_pgd_mapping(swapper_pg_dir, __phys_to_virt(start), size);
1406}
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417static int prevent_bootmem_remove_notifier(struct notifier_block *nb,
1418 unsigned long action, void *data)
1419{
1420 struct mem_section *ms;
1421 struct memory_notify *arg = data;
1422 unsigned long end_pfn = arg->start_pfn + arg->nr_pages;
1423 unsigned long pfn = arg->start_pfn;
1424
1425 if (action != MEM_GOING_OFFLINE)
1426 return NOTIFY_OK;
1427
1428 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1429 ms = __pfn_to_section(pfn);
1430 if (early_section(ms))
1431 return NOTIFY_BAD;
1432 }
1433 return NOTIFY_OK;
1434}
1435
1436static struct notifier_block prevent_bootmem_remove_nb = {
1437 .notifier_call = prevent_bootmem_remove_notifier,
1438};
1439
1440static int __init prevent_bootmem_remove_init(void)
1441{
1442 return register_memory_notifier(&prevent_bootmem_remove_nb);
1443}
1444device_initcall(prevent_bootmem_remove_init);
1445#endif
1446