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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/x86_64/mm/init.c
4 *
5 * Copyright (C) 1995 Linus Torvalds
6 * Copyright (C) 2000 Pavel Machek <pavel@ucw.cz>
7 * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
8 */
9
10#include <linux/signal.h>
11#include <linux/sched.h>
12#include <linux/kernel.h>
13#include <linux/errno.h>
14#include <linux/string.h>
15#include <linux/types.h>
16#include <linux/ptrace.h>
17#include <linux/mman.h>
18#include <linux/mm.h>
19#include <linux/swap.h>
20#include <linux/smp.h>
21#include <linux/init.h>
22#include <linux/initrd.h>
23#include <linux/pagemap.h>
24#include <linux/memblock.h>
25#include <linux/proc_fs.h>
26#include <linux/pci.h>
27#include <linux/pfn.h>
28#include <linux/poison.h>
29#include <linux/dma-mapping.h>
30#include <linux/memory.h>
31#include <linux/memory_hotplug.h>
32#include <linux/memremap.h>
33#include <linux/nmi.h>
34#include <linux/gfp.h>
35#include <linux/kcore.h>
36#include <linux/bootmem_info.h>
37
38#include <asm/processor.h>
39#include <asm/bios_ebda.h>
40#include <linux/uaccess.h>
41#include <asm/pgalloc.h>
42#include <asm/dma.h>
43#include <asm/fixmap.h>
44#include <asm/e820/api.h>
45#include <asm/apic.h>
46#include <asm/tlb.h>
47#include <asm/mmu_context.h>
48#include <asm/proto.h>
49#include <asm/smp.h>
50#include <asm/sections.h>
51#include <asm/kdebug.h>
52#include <asm/numa.h>
53#include <asm/set_memory.h>
54#include <asm/init.h>
55#include <asm/uv/uv.h>
56#include <asm/setup.h>
57#include <asm/ftrace.h>
58
59#include "mm_internal.h"
60
61#include "ident_map.c"
62
63#define DEFINE_POPULATE(fname, type1, type2, init) \
64static inline void fname##_init(struct mm_struct *mm, \
65 type1##_t *arg1, type2##_t *arg2, bool init) \
66{ \
67 if (init) \
68 fname##_safe(mm, arg1, arg2); \
69 else \
70 fname(mm, arg1, arg2); \
71}
72
73DEFINE_POPULATE(p4d_populate, p4d, pud, init)
74DEFINE_POPULATE(pgd_populate, pgd, p4d, init)
75DEFINE_POPULATE(pud_populate, pud, pmd, init)
76DEFINE_POPULATE(pmd_populate_kernel, pmd, pte, init)
77
78#define DEFINE_ENTRY(type1, type2, init) \
79static inline void set_##type1##_init(type1##_t *arg1, \
80 type2##_t arg2, bool init) \
81{ \
82 if (init) \
83 set_##type1##_safe(arg1, arg2); \
84 else \
85 set_##type1(arg1, arg2); \
86}
87
88DEFINE_ENTRY(p4d, p4d, init)
89DEFINE_ENTRY(pud, pud, init)
90DEFINE_ENTRY(pmd, pmd, init)
91DEFINE_ENTRY(pte, pte, init)
92
93static inline pgprot_t prot_sethuge(pgprot_t prot)
94{
95 WARN_ON_ONCE(pgprot_val(prot) & _PAGE_PAT);
96
97 return __pgprot(pgprot_val(prot) | _PAGE_PSE);
98}
99
100/*
101 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
102 * physical space so we can cache the place of the first one and move
103 * around without checking the pgd every time.
104 */
105
106/* Bits supported by the hardware: */
107pteval_t __supported_pte_mask __read_mostly = ~0;
108/* Bits allowed in normal kernel mappings: */
109pteval_t __default_kernel_pte_mask __read_mostly = ~0;
110EXPORT_SYMBOL_GPL(__supported_pte_mask);
111/* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
112EXPORT_SYMBOL(__default_kernel_pte_mask);
113
114int force_personality32;
115
116/*
117 * noexec32=on|off
118 * Control non executable heap for 32bit processes.
119 *
120 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
121 * off PROT_READ implies PROT_EXEC
122 */
123static int __init nonx32_setup(char *str)
124{
125 if (!strcmp(str, "on"))
126 force_personality32 &= ~READ_IMPLIES_EXEC;
127 else if (!strcmp(str, "off"))
128 force_personality32 |= READ_IMPLIES_EXEC;
129 return 1;
130}
131__setup("noexec32=", nonx32_setup);
132
133static void sync_global_pgds_l5(unsigned long start, unsigned long end)
134{
135 unsigned long addr;
136
137 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
138 const pgd_t *pgd_ref = pgd_offset_k(addr);
139 struct page *page;
140
141 /* Check for overflow */
142 if (addr < start)
143 break;
144
145 if (pgd_none(*pgd_ref))
146 continue;
147
148 spin_lock(&pgd_lock);
149 list_for_each_entry(page, &pgd_list, lru) {
150 pgd_t *pgd;
151 spinlock_t *pgt_lock;
152
153 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
154 /* the pgt_lock only for Xen */
155 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
156 spin_lock(pgt_lock);
157
158 if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
159 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
160
161 if (pgd_none(*pgd))
162 set_pgd(pgd, *pgd_ref);
163
164 spin_unlock(pgt_lock);
165 }
166 spin_unlock(&pgd_lock);
167 }
168}
169
170static void sync_global_pgds_l4(unsigned long start, unsigned long end)
171{
172 unsigned long addr;
173
174 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
175 pgd_t *pgd_ref = pgd_offset_k(addr);
176 const p4d_t *p4d_ref;
177 struct page *page;
178
179 /*
180 * With folded p4d, pgd_none() is always false, we need to
181 * handle synchronization on p4d level.
182 */
183 MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref));
184 p4d_ref = p4d_offset(pgd_ref, addr);
185
186 if (p4d_none(*p4d_ref))
187 continue;
188
189 spin_lock(&pgd_lock);
190 list_for_each_entry(page, &pgd_list, lru) {
191 pgd_t *pgd;
192 p4d_t *p4d;
193 spinlock_t *pgt_lock;
194
195 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
196 p4d = p4d_offset(pgd, addr);
197 /* the pgt_lock only for Xen */
198 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
199 spin_lock(pgt_lock);
200
201 if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
202 BUG_ON(p4d_pgtable(*p4d)
203 != p4d_pgtable(*p4d_ref));
204
205 if (p4d_none(*p4d))
206 set_p4d(p4d, *p4d_ref);
207
208 spin_unlock(pgt_lock);
209 }
210 spin_unlock(&pgd_lock);
211 }
212}
213
214/*
215 * When memory was added make sure all the processes MM have
216 * suitable PGD entries in the local PGD level page.
217 */
218static void sync_global_pgds(unsigned long start, unsigned long end)
219{
220 if (pgtable_l5_enabled())
221 sync_global_pgds_l5(start, end);
222 else
223 sync_global_pgds_l4(start, end);
224}
225
226/*
227 * NOTE: This function is marked __ref because it calls __init function
228 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
229 */
230static __ref void *spp_getpage(void)
231{
232 void *ptr;
233
234 if (after_bootmem)
235 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
236 else
237 ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
238
239 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
240 panic("set_pte_phys: cannot allocate page data %s\n",
241 after_bootmem ? "after bootmem" : "");
242 }
243
244 pr_debug("spp_getpage %p\n", ptr);
245
246 return ptr;
247}
248
249static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
250{
251 if (pgd_none(*pgd)) {
252 p4d_t *p4d = (p4d_t *)spp_getpage();
253 pgd_populate(&init_mm, pgd, p4d);
254 if (p4d != p4d_offset(pgd, 0))
255 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
256 p4d, p4d_offset(pgd, 0));
257 }
258 return p4d_offset(pgd, vaddr);
259}
260
261static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
262{
263 if (p4d_none(*p4d)) {
264 pud_t *pud = (pud_t *)spp_getpage();
265 p4d_populate(&init_mm, p4d, pud);
266 if (pud != pud_offset(p4d, 0))
267 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
268 pud, pud_offset(p4d, 0));
269 }
270 return pud_offset(p4d, vaddr);
271}
272
273static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
274{
275 if (pud_none(*pud)) {
276 pmd_t *pmd = (pmd_t *) spp_getpage();
277 pud_populate(&init_mm, pud, pmd);
278 if (pmd != pmd_offset(pud, 0))
279 printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
280 pmd, pmd_offset(pud, 0));
281 }
282 return pmd_offset(pud, vaddr);
283}
284
285static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
286{
287 if (pmd_none(*pmd)) {
288 pte_t *pte = (pte_t *) spp_getpage();
289 pmd_populate_kernel(&init_mm, pmd, pte);
290 if (pte != pte_offset_kernel(pmd, 0))
291 printk(KERN_ERR "PAGETABLE BUG #03!\n");
292 }
293 return pte_offset_kernel(pmd, vaddr);
294}
295
296static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
297{
298 pmd_t *pmd = fill_pmd(pud, vaddr);
299 pte_t *pte = fill_pte(pmd, vaddr);
300
301 set_pte(pte, new_pte);
302
303 /*
304 * It's enough to flush this one mapping.
305 * (PGE mappings get flushed as well)
306 */
307 flush_tlb_one_kernel(vaddr);
308}
309
310void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
311{
312 p4d_t *p4d = p4d_page + p4d_index(vaddr);
313 pud_t *pud = fill_pud(p4d, vaddr);
314
315 __set_pte_vaddr(pud, vaddr, new_pte);
316}
317
318void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
319{
320 pud_t *pud = pud_page + pud_index(vaddr);
321
322 __set_pte_vaddr(pud, vaddr, new_pte);
323}
324
325void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
326{
327 pgd_t *pgd;
328 p4d_t *p4d_page;
329
330 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
331
332 pgd = pgd_offset_k(vaddr);
333 if (pgd_none(*pgd)) {
334 printk(KERN_ERR
335 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
336 return;
337 }
338
339 p4d_page = p4d_offset(pgd, 0);
340 set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
341}
342
343pmd_t * __init populate_extra_pmd(unsigned long vaddr)
344{
345 pgd_t *pgd;
346 p4d_t *p4d;
347 pud_t *pud;
348
349 pgd = pgd_offset_k(vaddr);
350 p4d = fill_p4d(pgd, vaddr);
351 pud = fill_pud(p4d, vaddr);
352 return fill_pmd(pud, vaddr);
353}
354
355pte_t * __init populate_extra_pte(unsigned long vaddr)
356{
357 pmd_t *pmd;
358
359 pmd = populate_extra_pmd(vaddr);
360 return fill_pte(pmd, vaddr);
361}
362
363/*
364 * Create large page table mappings for a range of physical addresses.
365 */
366static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
367 enum page_cache_mode cache)
368{
369 pgd_t *pgd;
370 p4d_t *p4d;
371 pud_t *pud;
372 pmd_t *pmd;
373 pgprot_t prot;
374
375 pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
376 protval_4k_2_large(cachemode2protval(cache));
377 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
378 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
379 pgd = pgd_offset_k((unsigned long)__va(phys));
380 if (pgd_none(*pgd)) {
381 p4d = (p4d_t *) spp_getpage();
382 set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
383 _PAGE_USER));
384 }
385 p4d = p4d_offset(pgd, (unsigned long)__va(phys));
386 if (p4d_none(*p4d)) {
387 pud = (pud_t *) spp_getpage();
388 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
389 _PAGE_USER));
390 }
391 pud = pud_offset(p4d, (unsigned long)__va(phys));
392 if (pud_none(*pud)) {
393 pmd = (pmd_t *) spp_getpage();
394 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
395 _PAGE_USER));
396 }
397 pmd = pmd_offset(pud, phys);
398 BUG_ON(!pmd_none(*pmd));
399 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
400 }
401}
402
403void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
404{
405 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
406}
407
408void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
409{
410 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
411}
412
413/*
414 * The head.S code sets up the kernel high mapping:
415 *
416 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
417 *
418 * phys_base holds the negative offset to the kernel, which is added
419 * to the compile time generated pmds. This results in invalid pmds up
420 * to the point where we hit the physaddr 0 mapping.
421 *
422 * We limit the mappings to the region from _text to _brk_end. _brk_end
423 * is rounded up to the 2MB boundary. This catches the invalid pmds as
424 * well, as they are located before _text:
425 */
426void __init cleanup_highmap(void)
427{
428 unsigned long vaddr = __START_KERNEL_map;
429 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
430 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
431 pmd_t *pmd = level2_kernel_pgt;
432
433 /*
434 * Native path, max_pfn_mapped is not set yet.
435 * Xen has valid max_pfn_mapped set in
436 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
437 */
438 if (max_pfn_mapped)
439 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
440
441 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
442 if (pmd_none(*pmd))
443 continue;
444 if (vaddr < (unsigned long) _text || vaddr > end)
445 set_pmd(pmd, __pmd(0));
446 }
447}
448
449/*
450 * Create PTE level page table mapping for physical addresses.
451 * It returns the last physical address mapped.
452 */
453static unsigned long __meminit
454phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
455 pgprot_t prot, bool init)
456{
457 unsigned long pages = 0, paddr_next;
458 unsigned long paddr_last = paddr_end;
459 pte_t *pte;
460 int i;
461
462 pte = pte_page + pte_index(paddr);
463 i = pte_index(paddr);
464
465 for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
466 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
467 if (paddr >= paddr_end) {
468 if (!after_bootmem &&
469 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
470 E820_TYPE_RAM) &&
471 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
472 E820_TYPE_RESERVED_KERN))
473 set_pte_init(pte, __pte(0), init);
474 continue;
475 }
476
477 /*
478 * We will re-use the existing mapping.
479 * Xen for example has some special requirements, like mapping
480 * pagetable pages as RO. So assume someone who pre-setup
481 * these mappings are more intelligent.
482 */
483 if (!pte_none(*pte)) {
484 if (!after_bootmem)
485 pages++;
486 continue;
487 }
488
489 if (0)
490 pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr,
491 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
492 pages++;
493 set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init);
494 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
495 }
496
497 update_page_count(PG_LEVEL_4K, pages);
498
499 return paddr_last;
500}
501
502/*
503 * Create PMD level page table mapping for physical addresses. The virtual
504 * and physical address have to be aligned at this level.
505 * It returns the last physical address mapped.
506 */
507static unsigned long __meminit
508phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
509 unsigned long page_size_mask, pgprot_t prot, bool init)
510{
511 unsigned long pages = 0, paddr_next;
512 unsigned long paddr_last = paddr_end;
513
514 int i = pmd_index(paddr);
515
516 for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
517 pmd_t *pmd = pmd_page + pmd_index(paddr);
518 pte_t *pte;
519 pgprot_t new_prot = prot;
520
521 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
522 if (paddr >= paddr_end) {
523 if (!after_bootmem &&
524 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
525 E820_TYPE_RAM) &&
526 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
527 E820_TYPE_RESERVED_KERN))
528 set_pmd_init(pmd, __pmd(0), init);
529 continue;
530 }
531
532 if (!pmd_none(*pmd)) {
533 if (!pmd_large(*pmd)) {
534 spin_lock(&init_mm.page_table_lock);
535 pte = (pte_t *)pmd_page_vaddr(*pmd);
536 paddr_last = phys_pte_init(pte, paddr,
537 paddr_end, prot,
538 init);
539 spin_unlock(&init_mm.page_table_lock);
540 continue;
541 }
542 /*
543 * If we are ok with PG_LEVEL_2M mapping, then we will
544 * use the existing mapping,
545 *
546 * Otherwise, we will split the large page mapping but
547 * use the same existing protection bits except for
548 * large page, so that we don't violate Intel's TLB
549 * Application note (317080) which says, while changing
550 * the page sizes, new and old translations should
551 * not differ with respect to page frame and
552 * attributes.
553 */
554 if (page_size_mask & (1 << PG_LEVEL_2M)) {
555 if (!after_bootmem)
556 pages++;
557 paddr_last = paddr_next;
558 continue;
559 }
560 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
561 }
562
563 if (page_size_mask & (1<<PG_LEVEL_2M)) {
564 pages++;
565 spin_lock(&init_mm.page_table_lock);
566 set_pmd_init(pmd,
567 pfn_pmd(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
568 init);
569 spin_unlock(&init_mm.page_table_lock);
570 paddr_last = paddr_next;
571 continue;
572 }
573
574 pte = alloc_low_page();
575 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init);
576
577 spin_lock(&init_mm.page_table_lock);
578 pmd_populate_kernel_init(&init_mm, pmd, pte, init);
579 spin_unlock(&init_mm.page_table_lock);
580 }
581 update_page_count(PG_LEVEL_2M, pages);
582 return paddr_last;
583}
584
585/*
586 * Create PUD level page table mapping for physical addresses. The virtual
587 * and physical address do not have to be aligned at this level. KASLR can
588 * randomize virtual addresses up to this level.
589 * It returns the last physical address mapped.
590 */
591static unsigned long __meminit
592phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
593 unsigned long page_size_mask, pgprot_t _prot, bool init)
594{
595 unsigned long pages = 0, paddr_next;
596 unsigned long paddr_last = paddr_end;
597 unsigned long vaddr = (unsigned long)__va(paddr);
598 int i = pud_index(vaddr);
599
600 for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
601 pud_t *pud;
602 pmd_t *pmd;
603 pgprot_t prot = _prot;
604
605 vaddr = (unsigned long)__va(paddr);
606 pud = pud_page + pud_index(vaddr);
607 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
608
609 if (paddr >= paddr_end) {
610 if (!after_bootmem &&
611 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
612 E820_TYPE_RAM) &&
613 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
614 E820_TYPE_RESERVED_KERN))
615 set_pud_init(pud, __pud(0), init);
616 continue;
617 }
618
619 if (!pud_none(*pud)) {
620 if (!pud_large(*pud)) {
621 pmd = pmd_offset(pud, 0);
622 paddr_last = phys_pmd_init(pmd, paddr,
623 paddr_end,
624 page_size_mask,
625 prot, init);
626 continue;
627 }
628 /*
629 * If we are ok with PG_LEVEL_1G mapping, then we will
630 * use the existing mapping.
631 *
632 * Otherwise, we will split the gbpage mapping but use
633 * the same existing protection bits except for large
634 * page, so that we don't violate Intel's TLB
635 * Application note (317080) which says, while changing
636 * the page sizes, new and old translations should
637 * not differ with respect to page frame and
638 * attributes.
639 */
640 if (page_size_mask & (1 << PG_LEVEL_1G)) {
641 if (!after_bootmem)
642 pages++;
643 paddr_last = paddr_next;
644 continue;
645 }
646 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
647 }
648
649 if (page_size_mask & (1<<PG_LEVEL_1G)) {
650 pages++;
651 spin_lock(&init_mm.page_table_lock);
652 set_pud_init(pud,
653 pfn_pud(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
654 init);
655 spin_unlock(&init_mm.page_table_lock);
656 paddr_last = paddr_next;
657 continue;
658 }
659
660 pmd = alloc_low_page();
661 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
662 page_size_mask, prot, init);
663
664 spin_lock(&init_mm.page_table_lock);
665 pud_populate_init(&init_mm, pud, pmd, init);
666 spin_unlock(&init_mm.page_table_lock);
667 }
668
669 update_page_count(PG_LEVEL_1G, pages);
670
671 return paddr_last;
672}
673
674static unsigned long __meminit
675phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
676 unsigned long page_size_mask, pgprot_t prot, bool init)
677{
678 unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last;
679
680 paddr_last = paddr_end;
681 vaddr = (unsigned long)__va(paddr);
682 vaddr_end = (unsigned long)__va(paddr_end);
683
684 if (!pgtable_l5_enabled())
685 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end,
686 page_size_mask, prot, init);
687
688 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
689 p4d_t *p4d = p4d_page + p4d_index(vaddr);
690 pud_t *pud;
691
692 vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE;
693 paddr = __pa(vaddr);
694
695 if (paddr >= paddr_end) {
696 paddr_next = __pa(vaddr_next);
697 if (!after_bootmem &&
698 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
699 E820_TYPE_RAM) &&
700 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
701 E820_TYPE_RESERVED_KERN))
702 set_p4d_init(p4d, __p4d(0), init);
703 continue;
704 }
705
706 if (!p4d_none(*p4d)) {
707 pud = pud_offset(p4d, 0);
708 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
709 page_size_mask, prot, init);
710 continue;
711 }
712
713 pud = alloc_low_page();
714 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
715 page_size_mask, prot, init);
716
717 spin_lock(&init_mm.page_table_lock);
718 p4d_populate_init(&init_mm, p4d, pud, init);
719 spin_unlock(&init_mm.page_table_lock);
720 }
721
722 return paddr_last;
723}
724
725static unsigned long __meminit
726__kernel_physical_mapping_init(unsigned long paddr_start,
727 unsigned long paddr_end,
728 unsigned long page_size_mask,
729 pgprot_t prot, bool init)
730{
731 bool pgd_changed = false;
732 unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
733
734 paddr_last = paddr_end;
735 vaddr = (unsigned long)__va(paddr_start);
736 vaddr_end = (unsigned long)__va(paddr_end);
737 vaddr_start = vaddr;
738
739 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
740 pgd_t *pgd = pgd_offset_k(vaddr);
741 p4d_t *p4d;
742
743 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
744
745 if (pgd_val(*pgd)) {
746 p4d = (p4d_t *)pgd_page_vaddr(*pgd);
747 paddr_last = phys_p4d_init(p4d, __pa(vaddr),
748 __pa(vaddr_end),
749 page_size_mask,
750 prot, init);
751 continue;
752 }
753
754 p4d = alloc_low_page();
755 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
756 page_size_mask, prot, init);
757
758 spin_lock(&init_mm.page_table_lock);
759 if (pgtable_l5_enabled())
760 pgd_populate_init(&init_mm, pgd, p4d, init);
761 else
762 p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr),
763 (pud_t *) p4d, init);
764
765 spin_unlock(&init_mm.page_table_lock);
766 pgd_changed = true;
767 }
768
769 if (pgd_changed)
770 sync_global_pgds(vaddr_start, vaddr_end - 1);
771
772 return paddr_last;
773}
774
775
776/*
777 * Create page table mapping for the physical memory for specific physical
778 * addresses. Note that it can only be used to populate non-present entries.
779 * The virtual and physical addresses have to be aligned on PMD level
780 * down. It returns the last physical address mapped.
781 */
782unsigned long __meminit
783kernel_physical_mapping_init(unsigned long paddr_start,
784 unsigned long paddr_end,
785 unsigned long page_size_mask, pgprot_t prot)
786{
787 return __kernel_physical_mapping_init(paddr_start, paddr_end,
788 page_size_mask, prot, true);
789}
790
791/*
792 * This function is similar to kernel_physical_mapping_init() above with the
793 * exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe()
794 * when updating the mapping. The caller is responsible to flush the TLBs after
795 * the function returns.
796 */
797unsigned long __meminit
798kernel_physical_mapping_change(unsigned long paddr_start,
799 unsigned long paddr_end,
800 unsigned long page_size_mask)
801{
802 return __kernel_physical_mapping_init(paddr_start, paddr_end,
803 page_size_mask, PAGE_KERNEL,
804 false);
805}
806
807#ifndef CONFIG_NUMA
808void __init initmem_init(void)
809{
810 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
811}
812#endif
813
814void __init paging_init(void)
815{
816 sparse_init();
817
818 /*
819 * clear the default setting with node 0
820 * note: don't use nodes_clear here, that is really clearing when
821 * numa support is not compiled in, and later node_set_state
822 * will not set it back.
823 */
824 node_clear_state(0, N_MEMORY);
825 node_clear_state(0, N_NORMAL_MEMORY);
826
827 zone_sizes_init();
828}
829
830#ifdef CONFIG_SPARSEMEM_VMEMMAP
831#define PAGE_UNUSED 0xFD
832
833/*
834 * The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges
835 * from unused_pmd_start to next PMD_SIZE boundary.
836 */
837static unsigned long unused_pmd_start __meminitdata;
838
839static void __meminit vmemmap_flush_unused_pmd(void)
840{
841 if (!unused_pmd_start)
842 return;
843 /*
844 * Clears (unused_pmd_start, PMD_END]
845 */
846 memset((void *)unused_pmd_start, PAGE_UNUSED,
847 ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start);
848 unused_pmd_start = 0;
849}
850
851#ifdef CONFIG_MEMORY_HOTPLUG
852/* Returns true if the PMD is completely unused and thus it can be freed */
853static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end)
854{
855 unsigned long start = ALIGN_DOWN(addr, PMD_SIZE);
856
857 /*
858 * Flush the unused range cache to ensure that memchr_inv() will work
859 * for the whole range.
860 */
861 vmemmap_flush_unused_pmd();
862 memset((void *)addr, PAGE_UNUSED, end - addr);
863
864 return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE);
865}
866#endif
867
868static void __meminit __vmemmap_use_sub_pmd(unsigned long start)
869{
870 /*
871 * As we expect to add in the same granularity as we remove, it's
872 * sufficient to mark only some piece used to block the memmap page from
873 * getting removed when removing some other adjacent memmap (just in
874 * case the first memmap never gets initialized e.g., because the memory
875 * block never gets onlined).
876 */
877 memset((void *)start, 0, sizeof(struct page));
878}
879
880static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end)
881{
882 /*
883 * We only optimize if the new used range directly follows the
884 * previously unused range (esp., when populating consecutive sections).
885 */
886 if (unused_pmd_start == start) {
887 if (likely(IS_ALIGNED(end, PMD_SIZE)))
888 unused_pmd_start = 0;
889 else
890 unused_pmd_start = end;
891 return;
892 }
893
894 /*
895 * If the range does not contiguously follows previous one, make sure
896 * to mark the unused range of the previous one so it can be removed.
897 */
898 vmemmap_flush_unused_pmd();
899 __vmemmap_use_sub_pmd(start);
900}
901
902
903static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
904{
905 const unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
906
907 vmemmap_flush_unused_pmd();
908
909 /*
910 * Could be our memmap page is filled with PAGE_UNUSED already from a
911 * previous remove. Make sure to reset it.
912 */
913 __vmemmap_use_sub_pmd(start);
914
915 /*
916 * Mark with PAGE_UNUSED the unused parts of the new memmap range
917 */
918 if (!IS_ALIGNED(start, PMD_SIZE))
919 memset((void *)page, PAGE_UNUSED, start - page);
920
921 /*
922 * We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of
923 * consecutive sections. Remember for the last added PMD where the
924 * unused range begins.
925 */
926 if (!IS_ALIGNED(end, PMD_SIZE))
927 unused_pmd_start = end;
928}
929#endif
930
931/*
932 * Memory hotplug specific functions
933 */
934#ifdef CONFIG_MEMORY_HOTPLUG
935/*
936 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
937 * updating.
938 */
939static void update_end_of_memory_vars(u64 start, u64 size)
940{
941 unsigned long end_pfn = PFN_UP(start + size);
942
943 if (end_pfn > max_pfn) {
944 max_pfn = end_pfn;
945 max_low_pfn = end_pfn;
946 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
947 }
948}
949
950int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
951 struct mhp_params *params)
952{
953 int ret;
954
955 ret = __add_pages(nid, start_pfn, nr_pages, params);
956 WARN_ON_ONCE(ret);
957
958 /* update max_pfn, max_low_pfn and high_memory */
959 update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
960 nr_pages << PAGE_SHIFT);
961
962 return ret;
963}
964
965int arch_add_memory(int nid, u64 start, u64 size,
966 struct mhp_params *params)
967{
968 unsigned long start_pfn = start >> PAGE_SHIFT;
969 unsigned long nr_pages = size >> PAGE_SHIFT;
970
971 init_memory_mapping(start, start + size, params->pgprot);
972
973 return add_pages(nid, start_pfn, nr_pages, params);
974}
975
976static void __meminit free_pagetable(struct page *page, int order)
977{
978 unsigned long magic;
979 unsigned int nr_pages = 1 << order;
980
981 /* bootmem page has reserved flag */
982 if (PageReserved(page)) {
983 __ClearPageReserved(page);
984
985 magic = page->index;
986 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
987 while (nr_pages--)
988 put_page_bootmem(page++);
989 } else
990 while (nr_pages--)
991 free_reserved_page(page++);
992 } else
993 free_pages((unsigned long)page_address(page), order);
994}
995
996static void __meminit free_hugepage_table(struct page *page,
997 struct vmem_altmap *altmap)
998{
999 if (altmap)
1000 vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE);
1001 else
1002 free_pagetable(page, get_order(PMD_SIZE));
1003}
1004
1005static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
1006{
1007 pte_t *pte;
1008 int i;
1009
1010 for (i = 0; i < PTRS_PER_PTE; i++) {
1011 pte = pte_start + i;
1012 if (!pte_none(*pte))
1013 return;
1014 }
1015
1016 /* free a pte talbe */
1017 free_pagetable(pmd_page(*pmd), 0);
1018 spin_lock(&init_mm.page_table_lock);
1019 pmd_clear(pmd);
1020 spin_unlock(&init_mm.page_table_lock);
1021}
1022
1023static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
1024{
1025 pmd_t *pmd;
1026 int i;
1027
1028 for (i = 0; i < PTRS_PER_PMD; i++) {
1029 pmd = pmd_start + i;
1030 if (!pmd_none(*pmd))
1031 return;
1032 }
1033
1034 /* free a pmd talbe */
1035 free_pagetable(pud_page(*pud), 0);
1036 spin_lock(&init_mm.page_table_lock);
1037 pud_clear(pud);
1038 spin_unlock(&init_mm.page_table_lock);
1039}
1040
1041static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
1042{
1043 pud_t *pud;
1044 int i;
1045
1046 for (i = 0; i < PTRS_PER_PUD; i++) {
1047 pud = pud_start + i;
1048 if (!pud_none(*pud))
1049 return;
1050 }
1051
1052 /* free a pud talbe */
1053 free_pagetable(p4d_page(*p4d), 0);
1054 spin_lock(&init_mm.page_table_lock);
1055 p4d_clear(p4d);
1056 spin_unlock(&init_mm.page_table_lock);
1057}
1058
1059static void __meminit
1060remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
1061 bool direct)
1062{
1063 unsigned long next, pages = 0;
1064 pte_t *pte;
1065 phys_addr_t phys_addr;
1066
1067 pte = pte_start + pte_index(addr);
1068 for (; addr < end; addr = next, pte++) {
1069 next = (addr + PAGE_SIZE) & PAGE_MASK;
1070 if (next > end)
1071 next = end;
1072
1073 if (!pte_present(*pte))
1074 continue;
1075
1076 /*
1077 * We mapped [0,1G) memory as identity mapping when
1078 * initializing, in arch/x86/kernel/head_64.S. These
1079 * pagetables cannot be removed.
1080 */
1081 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
1082 if (phys_addr < (phys_addr_t)0x40000000)
1083 return;
1084
1085 if (!direct)
1086 free_pagetable(pte_page(*pte), 0);
1087
1088 spin_lock(&init_mm.page_table_lock);
1089 pte_clear(&init_mm, addr, pte);
1090 spin_unlock(&init_mm.page_table_lock);
1091
1092 /* For non-direct mapping, pages means nothing. */
1093 pages++;
1094 }
1095
1096 /* Call free_pte_table() in remove_pmd_table(). */
1097 flush_tlb_all();
1098 if (direct)
1099 update_page_count(PG_LEVEL_4K, -pages);
1100}
1101
1102static void __meminit
1103remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
1104 bool direct, struct vmem_altmap *altmap)
1105{
1106 unsigned long next, pages = 0;
1107 pte_t *pte_base;
1108 pmd_t *pmd;
1109
1110 pmd = pmd_start + pmd_index(addr);
1111 for (; addr < end; addr = next, pmd++) {
1112 next = pmd_addr_end(addr, end);
1113
1114 if (!pmd_present(*pmd))
1115 continue;
1116
1117 if (pmd_large(*pmd)) {
1118 if (IS_ALIGNED(addr, PMD_SIZE) &&
1119 IS_ALIGNED(next, PMD_SIZE)) {
1120 if (!direct)
1121 free_hugepage_table(pmd_page(*pmd),
1122 altmap);
1123
1124 spin_lock(&init_mm.page_table_lock);
1125 pmd_clear(pmd);
1126 spin_unlock(&init_mm.page_table_lock);
1127 pages++;
1128 }
1129#ifdef CONFIG_SPARSEMEM_VMEMMAP
1130 else if (vmemmap_pmd_is_unused(addr, next)) {
1131 free_hugepage_table(pmd_page(*pmd),
1132 altmap);
1133 spin_lock(&init_mm.page_table_lock);
1134 pmd_clear(pmd);
1135 spin_unlock(&init_mm.page_table_lock);
1136 }
1137#endif
1138 continue;
1139 }
1140
1141 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
1142 remove_pte_table(pte_base, addr, next, direct);
1143 free_pte_table(pte_base, pmd);
1144 }
1145
1146 /* Call free_pmd_table() in remove_pud_table(). */
1147 if (direct)
1148 update_page_count(PG_LEVEL_2M, -pages);
1149}
1150
1151static void __meminit
1152remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
1153 struct vmem_altmap *altmap, bool direct)
1154{
1155 unsigned long next, pages = 0;
1156 pmd_t *pmd_base;
1157 pud_t *pud;
1158
1159 pud = pud_start + pud_index(addr);
1160 for (; addr < end; addr = next, pud++) {
1161 next = pud_addr_end(addr, end);
1162
1163 if (!pud_present(*pud))
1164 continue;
1165
1166 if (pud_large(*pud) &&
1167 IS_ALIGNED(addr, PUD_SIZE) &&
1168 IS_ALIGNED(next, PUD_SIZE)) {
1169 spin_lock(&init_mm.page_table_lock);
1170 pud_clear(pud);
1171 spin_unlock(&init_mm.page_table_lock);
1172 pages++;
1173 continue;
1174 }
1175
1176 pmd_base = pmd_offset(pud, 0);
1177 remove_pmd_table(pmd_base, addr, next, direct, altmap);
1178 free_pmd_table(pmd_base, pud);
1179 }
1180
1181 if (direct)
1182 update_page_count(PG_LEVEL_1G, -pages);
1183}
1184
1185static void __meminit
1186remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
1187 struct vmem_altmap *altmap, bool direct)
1188{
1189 unsigned long next, pages = 0;
1190 pud_t *pud_base;
1191 p4d_t *p4d;
1192
1193 p4d = p4d_start + p4d_index(addr);
1194 for (; addr < end; addr = next, p4d++) {
1195 next = p4d_addr_end(addr, end);
1196
1197 if (!p4d_present(*p4d))
1198 continue;
1199
1200 BUILD_BUG_ON(p4d_large(*p4d));
1201
1202 pud_base = pud_offset(p4d, 0);
1203 remove_pud_table(pud_base, addr, next, altmap, direct);
1204 /*
1205 * For 4-level page tables we do not want to free PUDs, but in the
1206 * 5-level case we should free them. This code will have to change
1207 * to adapt for boot-time switching between 4 and 5 level page tables.
1208 */
1209 if (pgtable_l5_enabled())
1210 free_pud_table(pud_base, p4d);
1211 }
1212
1213 if (direct)
1214 update_page_count(PG_LEVEL_512G, -pages);
1215}
1216
1217/* start and end are both virtual address. */
1218static void __meminit
1219remove_pagetable(unsigned long start, unsigned long end, bool direct,
1220 struct vmem_altmap *altmap)
1221{
1222 unsigned long next;
1223 unsigned long addr;
1224 pgd_t *pgd;
1225 p4d_t *p4d;
1226
1227 for (addr = start; addr < end; addr = next) {
1228 next = pgd_addr_end(addr, end);
1229
1230 pgd = pgd_offset_k(addr);
1231 if (!pgd_present(*pgd))
1232 continue;
1233
1234 p4d = p4d_offset(pgd, 0);
1235 remove_p4d_table(p4d, addr, next, altmap, direct);
1236 }
1237
1238 flush_tlb_all();
1239}
1240
1241void __ref vmemmap_free(unsigned long start, unsigned long end,
1242 struct vmem_altmap *altmap)
1243{
1244 VM_BUG_ON(!PAGE_ALIGNED(start));
1245 VM_BUG_ON(!PAGE_ALIGNED(end));
1246
1247 remove_pagetable(start, end, false, altmap);
1248}
1249
1250static void __meminit
1251kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1252{
1253 start = (unsigned long)__va(start);
1254 end = (unsigned long)__va(end);
1255
1256 remove_pagetable(start, end, true, NULL);
1257}
1258
1259void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
1260{
1261 unsigned long start_pfn = start >> PAGE_SHIFT;
1262 unsigned long nr_pages = size >> PAGE_SHIFT;
1263
1264 __remove_pages(start_pfn, nr_pages, altmap);
1265 kernel_physical_mapping_remove(start, start + size);
1266}
1267#endif /* CONFIG_MEMORY_HOTPLUG */
1268
1269static struct kcore_list kcore_vsyscall;
1270
1271static void __init register_page_bootmem_info(void)
1272{
1273#if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP)
1274 int i;
1275
1276 for_each_online_node(i)
1277 register_page_bootmem_info_node(NODE_DATA(i));
1278#endif
1279}
1280
1281/*
1282 * Pre-allocates page-table pages for the vmalloc area in the kernel page-table.
1283 * Only the level which needs to be synchronized between all page-tables is
1284 * allocated because the synchronization can be expensive.
1285 */
1286static void __init preallocate_vmalloc_pages(void)
1287{
1288 unsigned long addr;
1289 const char *lvl;
1290
1291 for (addr = VMALLOC_START; addr <= VMEMORY_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1292 pgd_t *pgd = pgd_offset_k(addr);
1293 p4d_t *p4d;
1294 pud_t *pud;
1295
1296 lvl = "p4d";
1297 p4d = p4d_alloc(&init_mm, pgd, addr);
1298 if (!p4d)
1299 goto failed;
1300
1301 if (pgtable_l5_enabled())
1302 continue;
1303
1304 /*
1305 * The goal here is to allocate all possibly required
1306 * hardware page tables pointed to by the top hardware
1307 * level.
1308 *
1309 * On 4-level systems, the P4D layer is folded away and
1310 * the above code does no preallocation. Below, go down
1311 * to the pud _software_ level to ensure the second
1312 * hardware level is allocated on 4-level systems too.
1313 */
1314 lvl = "pud";
1315 pud = pud_alloc(&init_mm, p4d, addr);
1316 if (!pud)
1317 goto failed;
1318 }
1319
1320 return;
1321
1322failed:
1323
1324 /*
1325 * The pages have to be there now or they will be missing in
1326 * process page-tables later.
1327 */
1328 panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl);
1329}
1330
1331void __init mem_init(void)
1332{
1333 pci_iommu_alloc();
1334
1335 /* clear_bss() already clear the empty_zero_page */
1336
1337 /* this will put all memory onto the freelists */
1338 memblock_free_all();
1339 after_bootmem = 1;
1340 x86_init.hyper.init_after_bootmem();
1341
1342 /*
1343 * Must be done after boot memory is put on freelist, because here we
1344 * might set fields in deferred struct pages that have not yet been
1345 * initialized, and memblock_free_all() initializes all the reserved
1346 * deferred pages for us.
1347 */
1348 register_page_bootmem_info();
1349
1350 /* Register memory areas for /proc/kcore */
1351 if (get_gate_vma(&init_mm))
1352 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
1353
1354 preallocate_vmalloc_pages();
1355}
1356
1357#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1358int __init deferred_page_init_max_threads(const struct cpumask *node_cpumask)
1359{
1360 /*
1361 * More CPUs always led to greater speedups on tested systems, up to
1362 * all the nodes' CPUs. Use all since the system is otherwise idle
1363 * now.
1364 */
1365 return max_t(int, cpumask_weight(node_cpumask), 1);
1366}
1367#endif
1368
1369int kernel_set_to_readonly;
1370
1371void mark_rodata_ro(void)
1372{
1373 unsigned long start = PFN_ALIGN(_text);
1374 unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1375 unsigned long end = (unsigned long)__end_rodata_hpage_align;
1376 unsigned long text_end = PFN_ALIGN(_etext);
1377 unsigned long rodata_end = PFN_ALIGN(__end_rodata);
1378 unsigned long all_end;
1379
1380 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1381 (end - start) >> 10);
1382 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1383
1384 kernel_set_to_readonly = 1;
1385
1386 /*
1387 * The rodata/data/bss/brk section (but not the kernel text!)
1388 * should also be not-executable.
1389 *
1390 * We align all_end to PMD_SIZE because the existing mapping
1391 * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1392 * split the PMD and the reminder between _brk_end and the end
1393 * of the PMD will remain mapped executable.
1394 *
1395 * Any PMD which was setup after the one which covers _brk_end
1396 * has been zapped already via cleanup_highmem().
1397 */
1398 all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1399 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1400
1401 set_ftrace_ops_ro();
1402
1403#ifdef CONFIG_CPA_DEBUG
1404 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1405 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1406
1407 printk(KERN_INFO "Testing CPA: again\n");
1408 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1409#endif
1410
1411 free_kernel_image_pages("unused kernel image (text/rodata gap)",
1412 (void *)text_end, (void *)rodata_start);
1413 free_kernel_image_pages("unused kernel image (rodata/data gap)",
1414 (void *)rodata_end, (void *)_sdata);
1415
1416 debug_checkwx();
1417}
1418
1419/*
1420 * Block size is the minimum amount of memory which can be hotplugged or
1421 * hotremoved. It must be power of two and must be equal or larger than
1422 * MIN_MEMORY_BLOCK_SIZE.
1423 */
1424#define MAX_BLOCK_SIZE (2UL << 30)
1425
1426/* Amount of ram needed to start using large blocks */
1427#define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30)
1428
1429/* Adjustable memory block size */
1430static unsigned long set_memory_block_size;
1431int __init set_memory_block_size_order(unsigned int order)
1432{
1433 unsigned long size = 1UL << order;
1434
1435 if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE)
1436 return -EINVAL;
1437
1438 set_memory_block_size = size;
1439 return 0;
1440}
1441
1442static unsigned long probe_memory_block_size(void)
1443{
1444 unsigned long boot_mem_end = max_pfn << PAGE_SHIFT;
1445 unsigned long bz;
1446
1447 /* If memory block size has been set, then use it */
1448 bz = set_memory_block_size;
1449 if (bz)
1450 goto done;
1451
1452 /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */
1453 if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) {
1454 bz = MIN_MEMORY_BLOCK_SIZE;
1455 goto done;
1456 }
1457
1458 /*
1459 * Use max block size to minimize overhead on bare metal, where
1460 * alignment for memory hotplug isn't a concern.
1461 */
1462 if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
1463 bz = MAX_BLOCK_SIZE;
1464 goto done;
1465 }
1466
1467 /* Find the largest allowed block size that aligns to memory end */
1468 for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) {
1469 if (IS_ALIGNED(boot_mem_end, bz))
1470 break;
1471 }
1472done:
1473 pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1474
1475 return bz;
1476}
1477
1478static unsigned long memory_block_size_probed;
1479unsigned long memory_block_size_bytes(void)
1480{
1481 if (!memory_block_size_probed)
1482 memory_block_size_probed = probe_memory_block_size();
1483
1484 return memory_block_size_probed;
1485}
1486
1487#ifdef CONFIG_SPARSEMEM_VMEMMAP
1488/*
1489 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1490 */
1491static long __meminitdata addr_start, addr_end;
1492static void __meminitdata *p_start, *p_end;
1493static int __meminitdata node_start;
1494
1495void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
1496 unsigned long addr, unsigned long next)
1497{
1498 pte_t entry;
1499
1500 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1501 PAGE_KERNEL_LARGE);
1502 set_pmd(pmd, __pmd(pte_val(entry)));
1503
1504 /* check to see if we have contiguous blocks */
1505 if (p_end != p || node_start != node) {
1506 if (p_start)
1507 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1508 addr_start, addr_end-1, p_start, p_end-1, node_start);
1509 addr_start = addr;
1510 node_start = node;
1511 p_start = p;
1512 }
1513
1514 addr_end = addr + PMD_SIZE;
1515 p_end = p + PMD_SIZE;
1516
1517 if (!IS_ALIGNED(addr, PMD_SIZE) ||
1518 !IS_ALIGNED(next, PMD_SIZE))
1519 vmemmap_use_new_sub_pmd(addr, next);
1520}
1521
1522int __meminit vmemmap_check_pmd(pmd_t *pmd, int node,
1523 unsigned long addr, unsigned long next)
1524{
1525 int large = pmd_large(*pmd);
1526
1527 if (pmd_large(*pmd)) {
1528 vmemmap_verify((pte_t *)pmd, node, addr, next);
1529 vmemmap_use_sub_pmd(addr, next);
1530 }
1531
1532 return large;
1533}
1534
1535int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1536 struct vmem_altmap *altmap)
1537{
1538 int err;
1539
1540 VM_BUG_ON(!PAGE_ALIGNED(start));
1541 VM_BUG_ON(!PAGE_ALIGNED(end));
1542
1543 if (end - start < PAGES_PER_SECTION * sizeof(struct page))
1544 err = vmemmap_populate_basepages(start, end, node, NULL);
1545 else if (boot_cpu_has(X86_FEATURE_PSE))
1546 err = vmemmap_populate_hugepages(start, end, node, altmap);
1547 else if (altmap) {
1548 pr_err_once("%s: no cpu support for altmap allocations\n",
1549 __func__);
1550 err = -ENOMEM;
1551 } else
1552 err = vmemmap_populate_basepages(start, end, node, NULL);
1553 if (!err)
1554 sync_global_pgds(start, end - 1);
1555 return err;
1556}
1557
1558#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
1559void register_page_bootmem_memmap(unsigned long section_nr,
1560 struct page *start_page, unsigned long nr_pages)
1561{
1562 unsigned long addr = (unsigned long)start_page;
1563 unsigned long end = (unsigned long)(start_page + nr_pages);
1564 unsigned long next;
1565 pgd_t *pgd;
1566 p4d_t *p4d;
1567 pud_t *pud;
1568 pmd_t *pmd;
1569 unsigned int nr_pmd_pages;
1570 struct page *page;
1571
1572 for (; addr < end; addr = next) {
1573 pte_t *pte = NULL;
1574
1575 pgd = pgd_offset_k(addr);
1576 if (pgd_none(*pgd)) {
1577 next = (addr + PAGE_SIZE) & PAGE_MASK;
1578 continue;
1579 }
1580 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1581
1582 p4d = p4d_offset(pgd, addr);
1583 if (p4d_none(*p4d)) {
1584 next = (addr + PAGE_SIZE) & PAGE_MASK;
1585 continue;
1586 }
1587 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
1588
1589 pud = pud_offset(p4d, addr);
1590 if (pud_none(*pud)) {
1591 next = (addr + PAGE_SIZE) & PAGE_MASK;
1592 continue;
1593 }
1594 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1595
1596 if (!boot_cpu_has(X86_FEATURE_PSE)) {
1597 next = (addr + PAGE_SIZE) & PAGE_MASK;
1598 pmd = pmd_offset(pud, addr);
1599 if (pmd_none(*pmd))
1600 continue;
1601 get_page_bootmem(section_nr, pmd_page(*pmd),
1602 MIX_SECTION_INFO);
1603
1604 pte = pte_offset_kernel(pmd, addr);
1605 if (pte_none(*pte))
1606 continue;
1607 get_page_bootmem(section_nr, pte_page(*pte),
1608 SECTION_INFO);
1609 } else {
1610 next = pmd_addr_end(addr, end);
1611
1612 pmd = pmd_offset(pud, addr);
1613 if (pmd_none(*pmd))
1614 continue;
1615
1616 nr_pmd_pages = 1 << get_order(PMD_SIZE);
1617 page = pmd_page(*pmd);
1618 while (nr_pmd_pages--)
1619 get_page_bootmem(section_nr, page++,
1620 SECTION_INFO);
1621 }
1622 }
1623}
1624#endif
1625
1626void __meminit vmemmap_populate_print_last(void)
1627{
1628 if (p_start) {
1629 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1630 addr_start, addr_end-1, p_start, p_end-1, node_start);
1631 p_start = NULL;
1632 p_end = NULL;
1633 node_start = 0;
1634 }
1635}
1636#endif
1/*
2 * linux/arch/x86_64/mm/init.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 * Copyright (C) 2000 Pavel Machek <pavel@ucw.cz>
6 * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
7 */
8
9#include <linux/signal.h>
10#include <linux/sched.h>
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/string.h>
14#include <linux/types.h>
15#include <linux/ptrace.h>
16#include <linux/mman.h>
17#include <linux/mm.h>
18#include <linux/swap.h>
19#include <linux/smp.h>
20#include <linux/init.h>
21#include <linux/initrd.h>
22#include <linux/pagemap.h>
23#include <linux/bootmem.h>
24#include <linux/memblock.h>
25#include <linux/proc_fs.h>
26#include <linux/pci.h>
27#include <linux/pfn.h>
28#include <linux/poison.h>
29#include <linux/dma-mapping.h>
30#include <linux/memory.h>
31#include <linux/memory_hotplug.h>
32#include <linux/memremap.h>
33#include <linux/nmi.h>
34#include <linux/gfp.h>
35#include <linux/kcore.h>
36
37#include <asm/processor.h>
38#include <asm/bios_ebda.h>
39#include <linux/uaccess.h>
40#include <asm/pgtable.h>
41#include <asm/pgalloc.h>
42#include <asm/dma.h>
43#include <asm/fixmap.h>
44#include <asm/e820/api.h>
45#include <asm/apic.h>
46#include <asm/tlb.h>
47#include <asm/mmu_context.h>
48#include <asm/proto.h>
49#include <asm/smp.h>
50#include <asm/sections.h>
51#include <asm/kdebug.h>
52#include <asm/numa.h>
53#include <asm/set_memory.h>
54#include <asm/init.h>
55#include <asm/uv/uv.h>
56#include <asm/setup.h>
57
58#include "mm_internal.h"
59
60#include "ident_map.c"
61
62/*
63 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
64 * physical space so we can cache the place of the first one and move
65 * around without checking the pgd every time.
66 */
67
68/* Bits supported by the hardware: */
69pteval_t __supported_pte_mask __read_mostly = ~0;
70/* Bits allowed in normal kernel mappings: */
71pteval_t __default_kernel_pte_mask __read_mostly = ~0;
72EXPORT_SYMBOL_GPL(__supported_pte_mask);
73/* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
74EXPORT_SYMBOL(__default_kernel_pte_mask);
75
76int force_personality32;
77
78/*
79 * noexec32=on|off
80 * Control non executable heap for 32bit processes.
81 * To control the stack too use noexec=off
82 *
83 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
84 * off PROT_READ implies PROT_EXEC
85 */
86static int __init nonx32_setup(char *str)
87{
88 if (!strcmp(str, "on"))
89 force_personality32 &= ~READ_IMPLIES_EXEC;
90 else if (!strcmp(str, "off"))
91 force_personality32 |= READ_IMPLIES_EXEC;
92 return 1;
93}
94__setup("noexec32=", nonx32_setup);
95
96static void sync_global_pgds_l5(unsigned long start, unsigned long end)
97{
98 unsigned long addr;
99
100 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
101 const pgd_t *pgd_ref = pgd_offset_k(addr);
102 struct page *page;
103
104 /* Check for overflow */
105 if (addr < start)
106 break;
107
108 if (pgd_none(*pgd_ref))
109 continue;
110
111 spin_lock(&pgd_lock);
112 list_for_each_entry(page, &pgd_list, lru) {
113 pgd_t *pgd;
114 spinlock_t *pgt_lock;
115
116 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
117 /* the pgt_lock only for Xen */
118 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
119 spin_lock(pgt_lock);
120
121 if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
122 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
123
124 if (pgd_none(*pgd))
125 set_pgd(pgd, *pgd_ref);
126
127 spin_unlock(pgt_lock);
128 }
129 spin_unlock(&pgd_lock);
130 }
131}
132
133static void sync_global_pgds_l4(unsigned long start, unsigned long end)
134{
135 unsigned long addr;
136
137 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
138 pgd_t *pgd_ref = pgd_offset_k(addr);
139 const p4d_t *p4d_ref;
140 struct page *page;
141
142 /*
143 * With folded p4d, pgd_none() is always false, we need to
144 * handle synchonization on p4d level.
145 */
146 MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref));
147 p4d_ref = p4d_offset(pgd_ref, addr);
148
149 if (p4d_none(*p4d_ref))
150 continue;
151
152 spin_lock(&pgd_lock);
153 list_for_each_entry(page, &pgd_list, lru) {
154 pgd_t *pgd;
155 p4d_t *p4d;
156 spinlock_t *pgt_lock;
157
158 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
159 p4d = p4d_offset(pgd, addr);
160 /* the pgt_lock only for Xen */
161 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
162 spin_lock(pgt_lock);
163
164 if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
165 BUG_ON(p4d_page_vaddr(*p4d)
166 != p4d_page_vaddr(*p4d_ref));
167
168 if (p4d_none(*p4d))
169 set_p4d(p4d, *p4d_ref);
170
171 spin_unlock(pgt_lock);
172 }
173 spin_unlock(&pgd_lock);
174 }
175}
176
177/*
178 * When memory was added make sure all the processes MM have
179 * suitable PGD entries in the local PGD level page.
180 */
181void sync_global_pgds(unsigned long start, unsigned long end)
182{
183 if (pgtable_l5_enabled)
184 sync_global_pgds_l5(start, end);
185 else
186 sync_global_pgds_l4(start, end);
187}
188
189/*
190 * NOTE: This function is marked __ref because it calls __init function
191 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
192 */
193static __ref void *spp_getpage(void)
194{
195 void *ptr;
196
197 if (after_bootmem)
198 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
199 else
200 ptr = alloc_bootmem_pages(PAGE_SIZE);
201
202 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
203 panic("set_pte_phys: cannot allocate page data %s\n",
204 after_bootmem ? "after bootmem" : "");
205 }
206
207 pr_debug("spp_getpage %p\n", ptr);
208
209 return ptr;
210}
211
212static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
213{
214 if (pgd_none(*pgd)) {
215 p4d_t *p4d = (p4d_t *)spp_getpage();
216 pgd_populate(&init_mm, pgd, p4d);
217 if (p4d != p4d_offset(pgd, 0))
218 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
219 p4d, p4d_offset(pgd, 0));
220 }
221 return p4d_offset(pgd, vaddr);
222}
223
224static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
225{
226 if (p4d_none(*p4d)) {
227 pud_t *pud = (pud_t *)spp_getpage();
228 p4d_populate(&init_mm, p4d, pud);
229 if (pud != pud_offset(p4d, 0))
230 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
231 pud, pud_offset(p4d, 0));
232 }
233 return pud_offset(p4d, vaddr);
234}
235
236static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
237{
238 if (pud_none(*pud)) {
239 pmd_t *pmd = (pmd_t *) spp_getpage();
240 pud_populate(&init_mm, pud, pmd);
241 if (pmd != pmd_offset(pud, 0))
242 printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
243 pmd, pmd_offset(pud, 0));
244 }
245 return pmd_offset(pud, vaddr);
246}
247
248static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
249{
250 if (pmd_none(*pmd)) {
251 pte_t *pte = (pte_t *) spp_getpage();
252 pmd_populate_kernel(&init_mm, pmd, pte);
253 if (pte != pte_offset_kernel(pmd, 0))
254 printk(KERN_ERR "PAGETABLE BUG #03!\n");
255 }
256 return pte_offset_kernel(pmd, vaddr);
257}
258
259static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
260{
261 pmd_t *pmd = fill_pmd(pud, vaddr);
262 pte_t *pte = fill_pte(pmd, vaddr);
263
264 set_pte(pte, new_pte);
265
266 /*
267 * It's enough to flush this one mapping.
268 * (PGE mappings get flushed as well)
269 */
270 __flush_tlb_one_kernel(vaddr);
271}
272
273void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
274{
275 p4d_t *p4d = p4d_page + p4d_index(vaddr);
276 pud_t *pud = fill_pud(p4d, vaddr);
277
278 __set_pte_vaddr(pud, vaddr, new_pte);
279}
280
281void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
282{
283 pud_t *pud = pud_page + pud_index(vaddr);
284
285 __set_pte_vaddr(pud, vaddr, new_pte);
286}
287
288void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
289{
290 pgd_t *pgd;
291 p4d_t *p4d_page;
292
293 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
294
295 pgd = pgd_offset_k(vaddr);
296 if (pgd_none(*pgd)) {
297 printk(KERN_ERR
298 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
299 return;
300 }
301
302 p4d_page = p4d_offset(pgd, 0);
303 set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
304}
305
306pmd_t * __init populate_extra_pmd(unsigned long vaddr)
307{
308 pgd_t *pgd;
309 p4d_t *p4d;
310 pud_t *pud;
311
312 pgd = pgd_offset_k(vaddr);
313 p4d = fill_p4d(pgd, vaddr);
314 pud = fill_pud(p4d, vaddr);
315 return fill_pmd(pud, vaddr);
316}
317
318pte_t * __init populate_extra_pte(unsigned long vaddr)
319{
320 pmd_t *pmd;
321
322 pmd = populate_extra_pmd(vaddr);
323 return fill_pte(pmd, vaddr);
324}
325
326/*
327 * Create large page table mappings for a range of physical addresses.
328 */
329static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
330 enum page_cache_mode cache)
331{
332 pgd_t *pgd;
333 p4d_t *p4d;
334 pud_t *pud;
335 pmd_t *pmd;
336 pgprot_t prot;
337
338 pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
339 pgprot_val(pgprot_4k_2_large(cachemode2pgprot(cache)));
340 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
341 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
342 pgd = pgd_offset_k((unsigned long)__va(phys));
343 if (pgd_none(*pgd)) {
344 p4d = (p4d_t *) spp_getpage();
345 set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
346 _PAGE_USER));
347 }
348 p4d = p4d_offset(pgd, (unsigned long)__va(phys));
349 if (p4d_none(*p4d)) {
350 pud = (pud_t *) spp_getpage();
351 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
352 _PAGE_USER));
353 }
354 pud = pud_offset(p4d, (unsigned long)__va(phys));
355 if (pud_none(*pud)) {
356 pmd = (pmd_t *) spp_getpage();
357 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
358 _PAGE_USER));
359 }
360 pmd = pmd_offset(pud, phys);
361 BUG_ON(!pmd_none(*pmd));
362 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
363 }
364}
365
366void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
367{
368 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
369}
370
371void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
372{
373 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
374}
375
376/*
377 * The head.S code sets up the kernel high mapping:
378 *
379 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
380 *
381 * phys_base holds the negative offset to the kernel, which is added
382 * to the compile time generated pmds. This results in invalid pmds up
383 * to the point where we hit the physaddr 0 mapping.
384 *
385 * We limit the mappings to the region from _text to _brk_end. _brk_end
386 * is rounded up to the 2MB boundary. This catches the invalid pmds as
387 * well, as they are located before _text:
388 */
389void __init cleanup_highmap(void)
390{
391 unsigned long vaddr = __START_KERNEL_map;
392 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
393 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
394 pmd_t *pmd = level2_kernel_pgt;
395
396 /*
397 * Native path, max_pfn_mapped is not set yet.
398 * Xen has valid max_pfn_mapped set in
399 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
400 */
401 if (max_pfn_mapped)
402 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
403
404 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
405 if (pmd_none(*pmd))
406 continue;
407 if (vaddr < (unsigned long) _text || vaddr > end)
408 set_pmd(pmd, __pmd(0));
409 }
410}
411
412/*
413 * Create PTE level page table mapping for physical addresses.
414 * It returns the last physical address mapped.
415 */
416static unsigned long __meminit
417phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
418 pgprot_t prot)
419{
420 unsigned long pages = 0, paddr_next;
421 unsigned long paddr_last = paddr_end;
422 pte_t *pte;
423 int i;
424
425 pte = pte_page + pte_index(paddr);
426 i = pte_index(paddr);
427
428 for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
429 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
430 if (paddr >= paddr_end) {
431 if (!after_bootmem &&
432 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
433 E820_TYPE_RAM) &&
434 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
435 E820_TYPE_RESERVED_KERN))
436 set_pte(pte, __pte(0));
437 continue;
438 }
439
440 /*
441 * We will re-use the existing mapping.
442 * Xen for example has some special requirements, like mapping
443 * pagetable pages as RO. So assume someone who pre-setup
444 * these mappings are more intelligent.
445 */
446 if (!pte_none(*pte)) {
447 if (!after_bootmem)
448 pages++;
449 continue;
450 }
451
452 if (0)
453 pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr,
454 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
455 pages++;
456 set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));
457 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
458 }
459
460 update_page_count(PG_LEVEL_4K, pages);
461
462 return paddr_last;
463}
464
465/*
466 * Create PMD level page table mapping for physical addresses. The virtual
467 * and physical address have to be aligned at this level.
468 * It returns the last physical address mapped.
469 */
470static unsigned long __meminit
471phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
472 unsigned long page_size_mask, pgprot_t prot)
473{
474 unsigned long pages = 0, paddr_next;
475 unsigned long paddr_last = paddr_end;
476
477 int i = pmd_index(paddr);
478
479 for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
480 pmd_t *pmd = pmd_page + pmd_index(paddr);
481 pte_t *pte;
482 pgprot_t new_prot = prot;
483
484 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
485 if (paddr >= paddr_end) {
486 if (!after_bootmem &&
487 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
488 E820_TYPE_RAM) &&
489 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
490 E820_TYPE_RESERVED_KERN))
491 set_pmd(pmd, __pmd(0));
492 continue;
493 }
494
495 if (!pmd_none(*pmd)) {
496 if (!pmd_large(*pmd)) {
497 spin_lock(&init_mm.page_table_lock);
498 pte = (pte_t *)pmd_page_vaddr(*pmd);
499 paddr_last = phys_pte_init(pte, paddr,
500 paddr_end, prot);
501 spin_unlock(&init_mm.page_table_lock);
502 continue;
503 }
504 /*
505 * If we are ok with PG_LEVEL_2M mapping, then we will
506 * use the existing mapping,
507 *
508 * Otherwise, we will split the large page mapping but
509 * use the same existing protection bits except for
510 * large page, so that we don't violate Intel's TLB
511 * Application note (317080) which says, while changing
512 * the page sizes, new and old translations should
513 * not differ with respect to page frame and
514 * attributes.
515 */
516 if (page_size_mask & (1 << PG_LEVEL_2M)) {
517 if (!after_bootmem)
518 pages++;
519 paddr_last = paddr_next;
520 continue;
521 }
522 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
523 }
524
525 if (page_size_mask & (1<<PG_LEVEL_2M)) {
526 pages++;
527 spin_lock(&init_mm.page_table_lock);
528 set_pte((pte_t *)pmd,
529 pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT,
530 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
531 spin_unlock(&init_mm.page_table_lock);
532 paddr_last = paddr_next;
533 continue;
534 }
535
536 pte = alloc_low_page();
537 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot);
538
539 spin_lock(&init_mm.page_table_lock);
540 pmd_populate_kernel(&init_mm, pmd, pte);
541 spin_unlock(&init_mm.page_table_lock);
542 }
543 update_page_count(PG_LEVEL_2M, pages);
544 return paddr_last;
545}
546
547/*
548 * Create PUD level page table mapping for physical addresses. The virtual
549 * and physical address do not have to be aligned at this level. KASLR can
550 * randomize virtual addresses up to this level.
551 * It returns the last physical address mapped.
552 */
553static unsigned long __meminit
554phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
555 unsigned long page_size_mask)
556{
557 unsigned long pages = 0, paddr_next;
558 unsigned long paddr_last = paddr_end;
559 unsigned long vaddr = (unsigned long)__va(paddr);
560 int i = pud_index(vaddr);
561
562 for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
563 pud_t *pud;
564 pmd_t *pmd;
565 pgprot_t prot = PAGE_KERNEL;
566
567 vaddr = (unsigned long)__va(paddr);
568 pud = pud_page + pud_index(vaddr);
569 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
570
571 if (paddr >= paddr_end) {
572 if (!after_bootmem &&
573 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
574 E820_TYPE_RAM) &&
575 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
576 E820_TYPE_RESERVED_KERN))
577 set_pud(pud, __pud(0));
578 continue;
579 }
580
581 if (!pud_none(*pud)) {
582 if (!pud_large(*pud)) {
583 pmd = pmd_offset(pud, 0);
584 paddr_last = phys_pmd_init(pmd, paddr,
585 paddr_end,
586 page_size_mask,
587 prot);
588 __flush_tlb_all();
589 continue;
590 }
591 /*
592 * If we are ok with PG_LEVEL_1G mapping, then we will
593 * use the existing mapping.
594 *
595 * Otherwise, we will split the gbpage mapping but use
596 * the same existing protection bits except for large
597 * page, so that we don't violate Intel's TLB
598 * Application note (317080) which says, while changing
599 * the page sizes, new and old translations should
600 * not differ with respect to page frame and
601 * attributes.
602 */
603 if (page_size_mask & (1 << PG_LEVEL_1G)) {
604 if (!after_bootmem)
605 pages++;
606 paddr_last = paddr_next;
607 continue;
608 }
609 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
610 }
611
612 if (page_size_mask & (1<<PG_LEVEL_1G)) {
613 pages++;
614 spin_lock(&init_mm.page_table_lock);
615 set_pte((pte_t *)pud,
616 pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,
617 PAGE_KERNEL_LARGE));
618 spin_unlock(&init_mm.page_table_lock);
619 paddr_last = paddr_next;
620 continue;
621 }
622
623 pmd = alloc_low_page();
624 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
625 page_size_mask, prot);
626
627 spin_lock(&init_mm.page_table_lock);
628 pud_populate(&init_mm, pud, pmd);
629 spin_unlock(&init_mm.page_table_lock);
630 }
631 __flush_tlb_all();
632
633 update_page_count(PG_LEVEL_1G, pages);
634
635 return paddr_last;
636}
637
638static unsigned long __meminit
639phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
640 unsigned long page_size_mask)
641{
642 unsigned long paddr_next, paddr_last = paddr_end;
643 unsigned long vaddr = (unsigned long)__va(paddr);
644 int i = p4d_index(vaddr);
645
646 if (!pgtable_l5_enabled)
647 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end, page_size_mask);
648
649 for (; i < PTRS_PER_P4D; i++, paddr = paddr_next) {
650 p4d_t *p4d;
651 pud_t *pud;
652
653 vaddr = (unsigned long)__va(paddr);
654 p4d = p4d_page + p4d_index(vaddr);
655 paddr_next = (paddr & P4D_MASK) + P4D_SIZE;
656
657 if (paddr >= paddr_end) {
658 if (!after_bootmem &&
659 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
660 E820_TYPE_RAM) &&
661 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
662 E820_TYPE_RESERVED_KERN))
663 set_p4d(p4d, __p4d(0));
664 continue;
665 }
666
667 if (!p4d_none(*p4d)) {
668 pud = pud_offset(p4d, 0);
669 paddr_last = phys_pud_init(pud, paddr,
670 paddr_end,
671 page_size_mask);
672 __flush_tlb_all();
673 continue;
674 }
675
676 pud = alloc_low_page();
677 paddr_last = phys_pud_init(pud, paddr, paddr_end,
678 page_size_mask);
679
680 spin_lock(&init_mm.page_table_lock);
681 p4d_populate(&init_mm, p4d, pud);
682 spin_unlock(&init_mm.page_table_lock);
683 }
684 __flush_tlb_all();
685
686 return paddr_last;
687}
688
689/*
690 * Create page table mapping for the physical memory for specific physical
691 * addresses. The virtual and physical addresses have to be aligned on PMD level
692 * down. It returns the last physical address mapped.
693 */
694unsigned long __meminit
695kernel_physical_mapping_init(unsigned long paddr_start,
696 unsigned long paddr_end,
697 unsigned long page_size_mask)
698{
699 bool pgd_changed = false;
700 unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
701
702 paddr_last = paddr_end;
703 vaddr = (unsigned long)__va(paddr_start);
704 vaddr_end = (unsigned long)__va(paddr_end);
705 vaddr_start = vaddr;
706
707 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
708 pgd_t *pgd = pgd_offset_k(vaddr);
709 p4d_t *p4d;
710
711 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
712
713 if (pgd_val(*pgd)) {
714 p4d = (p4d_t *)pgd_page_vaddr(*pgd);
715 paddr_last = phys_p4d_init(p4d, __pa(vaddr),
716 __pa(vaddr_end),
717 page_size_mask);
718 continue;
719 }
720
721 p4d = alloc_low_page();
722 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
723 page_size_mask);
724
725 spin_lock(&init_mm.page_table_lock);
726 if (pgtable_l5_enabled)
727 pgd_populate(&init_mm, pgd, p4d);
728 else
729 p4d_populate(&init_mm, p4d_offset(pgd, vaddr), (pud_t *) p4d);
730 spin_unlock(&init_mm.page_table_lock);
731 pgd_changed = true;
732 }
733
734 if (pgd_changed)
735 sync_global_pgds(vaddr_start, vaddr_end - 1);
736
737 __flush_tlb_all();
738
739 return paddr_last;
740}
741
742#ifndef CONFIG_NUMA
743void __init initmem_init(void)
744{
745 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
746}
747#endif
748
749void __init paging_init(void)
750{
751 sparse_memory_present_with_active_regions(MAX_NUMNODES);
752 sparse_init();
753
754 /*
755 * clear the default setting with node 0
756 * note: don't use nodes_clear here, that is really clearing when
757 * numa support is not compiled in, and later node_set_state
758 * will not set it back.
759 */
760 node_clear_state(0, N_MEMORY);
761 if (N_MEMORY != N_NORMAL_MEMORY)
762 node_clear_state(0, N_NORMAL_MEMORY);
763
764 zone_sizes_init();
765}
766
767/*
768 * Memory hotplug specific functions
769 */
770#ifdef CONFIG_MEMORY_HOTPLUG
771/*
772 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
773 * updating.
774 */
775static void update_end_of_memory_vars(u64 start, u64 size)
776{
777 unsigned long end_pfn = PFN_UP(start + size);
778
779 if (end_pfn > max_pfn) {
780 max_pfn = end_pfn;
781 max_low_pfn = end_pfn;
782 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
783 }
784}
785
786int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
787 struct vmem_altmap *altmap, bool want_memblock)
788{
789 int ret;
790
791 ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
792 WARN_ON_ONCE(ret);
793
794 /* update max_pfn, max_low_pfn and high_memory */
795 update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
796 nr_pages << PAGE_SHIFT);
797
798 return ret;
799}
800
801int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
802 bool want_memblock)
803{
804 unsigned long start_pfn = start >> PAGE_SHIFT;
805 unsigned long nr_pages = size >> PAGE_SHIFT;
806
807 init_memory_mapping(start, start + size);
808
809 return add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
810}
811
812#define PAGE_INUSE 0xFD
813
814static void __meminit free_pagetable(struct page *page, int order)
815{
816 unsigned long magic;
817 unsigned int nr_pages = 1 << order;
818
819 /* bootmem page has reserved flag */
820 if (PageReserved(page)) {
821 __ClearPageReserved(page);
822
823 magic = (unsigned long)page->freelist;
824 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
825 while (nr_pages--)
826 put_page_bootmem(page++);
827 } else
828 while (nr_pages--)
829 free_reserved_page(page++);
830 } else
831 free_pages((unsigned long)page_address(page), order);
832}
833
834static void __meminit free_hugepage_table(struct page *page,
835 struct vmem_altmap *altmap)
836{
837 if (altmap)
838 vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE);
839 else
840 free_pagetable(page, get_order(PMD_SIZE));
841}
842
843static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
844{
845 pte_t *pte;
846 int i;
847
848 for (i = 0; i < PTRS_PER_PTE; i++) {
849 pte = pte_start + i;
850 if (!pte_none(*pte))
851 return;
852 }
853
854 /* free a pte talbe */
855 free_pagetable(pmd_page(*pmd), 0);
856 spin_lock(&init_mm.page_table_lock);
857 pmd_clear(pmd);
858 spin_unlock(&init_mm.page_table_lock);
859}
860
861static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
862{
863 pmd_t *pmd;
864 int i;
865
866 for (i = 0; i < PTRS_PER_PMD; i++) {
867 pmd = pmd_start + i;
868 if (!pmd_none(*pmd))
869 return;
870 }
871
872 /* free a pmd talbe */
873 free_pagetable(pud_page(*pud), 0);
874 spin_lock(&init_mm.page_table_lock);
875 pud_clear(pud);
876 spin_unlock(&init_mm.page_table_lock);
877}
878
879static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
880{
881 pud_t *pud;
882 int i;
883
884 for (i = 0; i < PTRS_PER_PUD; i++) {
885 pud = pud_start + i;
886 if (!pud_none(*pud))
887 return;
888 }
889
890 /* free a pud talbe */
891 free_pagetable(p4d_page(*p4d), 0);
892 spin_lock(&init_mm.page_table_lock);
893 p4d_clear(p4d);
894 spin_unlock(&init_mm.page_table_lock);
895}
896
897static void __meminit
898remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
899 bool direct)
900{
901 unsigned long next, pages = 0;
902 pte_t *pte;
903 void *page_addr;
904 phys_addr_t phys_addr;
905
906 pte = pte_start + pte_index(addr);
907 for (; addr < end; addr = next, pte++) {
908 next = (addr + PAGE_SIZE) & PAGE_MASK;
909 if (next > end)
910 next = end;
911
912 if (!pte_present(*pte))
913 continue;
914
915 /*
916 * We mapped [0,1G) memory as identity mapping when
917 * initializing, in arch/x86/kernel/head_64.S. These
918 * pagetables cannot be removed.
919 */
920 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
921 if (phys_addr < (phys_addr_t)0x40000000)
922 return;
923
924 if (PAGE_ALIGNED(addr) && PAGE_ALIGNED(next)) {
925 /*
926 * Do not free direct mapping pages since they were
927 * freed when offlining, or simplely not in use.
928 */
929 if (!direct)
930 free_pagetable(pte_page(*pte), 0);
931
932 spin_lock(&init_mm.page_table_lock);
933 pte_clear(&init_mm, addr, pte);
934 spin_unlock(&init_mm.page_table_lock);
935
936 /* For non-direct mapping, pages means nothing. */
937 pages++;
938 } else {
939 /*
940 * If we are here, we are freeing vmemmap pages since
941 * direct mapped memory ranges to be freed are aligned.
942 *
943 * If we are not removing the whole page, it means
944 * other page structs in this page are being used and
945 * we canot remove them. So fill the unused page_structs
946 * with 0xFD, and remove the page when it is wholly
947 * filled with 0xFD.
948 */
949 memset((void *)addr, PAGE_INUSE, next - addr);
950
951 page_addr = page_address(pte_page(*pte));
952 if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
953 free_pagetable(pte_page(*pte), 0);
954
955 spin_lock(&init_mm.page_table_lock);
956 pte_clear(&init_mm, addr, pte);
957 spin_unlock(&init_mm.page_table_lock);
958 }
959 }
960 }
961
962 /* Call free_pte_table() in remove_pmd_table(). */
963 flush_tlb_all();
964 if (direct)
965 update_page_count(PG_LEVEL_4K, -pages);
966}
967
968static void __meminit
969remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
970 bool direct, struct vmem_altmap *altmap)
971{
972 unsigned long next, pages = 0;
973 pte_t *pte_base;
974 pmd_t *pmd;
975 void *page_addr;
976
977 pmd = pmd_start + pmd_index(addr);
978 for (; addr < end; addr = next, pmd++) {
979 next = pmd_addr_end(addr, end);
980
981 if (!pmd_present(*pmd))
982 continue;
983
984 if (pmd_large(*pmd)) {
985 if (IS_ALIGNED(addr, PMD_SIZE) &&
986 IS_ALIGNED(next, PMD_SIZE)) {
987 if (!direct)
988 free_hugepage_table(pmd_page(*pmd),
989 altmap);
990
991 spin_lock(&init_mm.page_table_lock);
992 pmd_clear(pmd);
993 spin_unlock(&init_mm.page_table_lock);
994 pages++;
995 } else {
996 /* If here, we are freeing vmemmap pages. */
997 memset((void *)addr, PAGE_INUSE, next - addr);
998
999 page_addr = page_address(pmd_page(*pmd));
1000 if (!memchr_inv(page_addr, PAGE_INUSE,
1001 PMD_SIZE)) {
1002 free_hugepage_table(pmd_page(*pmd),
1003 altmap);
1004
1005 spin_lock(&init_mm.page_table_lock);
1006 pmd_clear(pmd);
1007 spin_unlock(&init_mm.page_table_lock);
1008 }
1009 }
1010
1011 continue;
1012 }
1013
1014 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
1015 remove_pte_table(pte_base, addr, next, direct);
1016 free_pte_table(pte_base, pmd);
1017 }
1018
1019 /* Call free_pmd_table() in remove_pud_table(). */
1020 if (direct)
1021 update_page_count(PG_LEVEL_2M, -pages);
1022}
1023
1024static void __meminit
1025remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
1026 struct vmem_altmap *altmap, bool direct)
1027{
1028 unsigned long next, pages = 0;
1029 pmd_t *pmd_base;
1030 pud_t *pud;
1031 void *page_addr;
1032
1033 pud = pud_start + pud_index(addr);
1034 for (; addr < end; addr = next, pud++) {
1035 next = pud_addr_end(addr, end);
1036
1037 if (!pud_present(*pud))
1038 continue;
1039
1040 if (pud_large(*pud)) {
1041 if (IS_ALIGNED(addr, PUD_SIZE) &&
1042 IS_ALIGNED(next, PUD_SIZE)) {
1043 if (!direct)
1044 free_pagetable(pud_page(*pud),
1045 get_order(PUD_SIZE));
1046
1047 spin_lock(&init_mm.page_table_lock);
1048 pud_clear(pud);
1049 spin_unlock(&init_mm.page_table_lock);
1050 pages++;
1051 } else {
1052 /* If here, we are freeing vmemmap pages. */
1053 memset((void *)addr, PAGE_INUSE, next - addr);
1054
1055 page_addr = page_address(pud_page(*pud));
1056 if (!memchr_inv(page_addr, PAGE_INUSE,
1057 PUD_SIZE)) {
1058 free_pagetable(pud_page(*pud),
1059 get_order(PUD_SIZE));
1060
1061 spin_lock(&init_mm.page_table_lock);
1062 pud_clear(pud);
1063 spin_unlock(&init_mm.page_table_lock);
1064 }
1065 }
1066
1067 continue;
1068 }
1069
1070 pmd_base = pmd_offset(pud, 0);
1071 remove_pmd_table(pmd_base, addr, next, direct, altmap);
1072 free_pmd_table(pmd_base, pud);
1073 }
1074
1075 if (direct)
1076 update_page_count(PG_LEVEL_1G, -pages);
1077}
1078
1079static void __meminit
1080remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
1081 struct vmem_altmap *altmap, bool direct)
1082{
1083 unsigned long next, pages = 0;
1084 pud_t *pud_base;
1085 p4d_t *p4d;
1086
1087 p4d = p4d_start + p4d_index(addr);
1088 for (; addr < end; addr = next, p4d++) {
1089 next = p4d_addr_end(addr, end);
1090
1091 if (!p4d_present(*p4d))
1092 continue;
1093
1094 BUILD_BUG_ON(p4d_large(*p4d));
1095
1096 pud_base = pud_offset(p4d, 0);
1097 remove_pud_table(pud_base, addr, next, altmap, direct);
1098 /*
1099 * For 4-level page tables we do not want to free PUDs, but in the
1100 * 5-level case we should free them. This code will have to change
1101 * to adapt for boot-time switching between 4 and 5 level page tables.
1102 */
1103 if (pgtable_l5_enabled)
1104 free_pud_table(pud_base, p4d);
1105 }
1106
1107 if (direct)
1108 update_page_count(PG_LEVEL_512G, -pages);
1109}
1110
1111/* start and end are both virtual address. */
1112static void __meminit
1113remove_pagetable(unsigned long start, unsigned long end, bool direct,
1114 struct vmem_altmap *altmap)
1115{
1116 unsigned long next;
1117 unsigned long addr;
1118 pgd_t *pgd;
1119 p4d_t *p4d;
1120
1121 for (addr = start; addr < end; addr = next) {
1122 next = pgd_addr_end(addr, end);
1123
1124 pgd = pgd_offset_k(addr);
1125 if (!pgd_present(*pgd))
1126 continue;
1127
1128 p4d = p4d_offset(pgd, 0);
1129 remove_p4d_table(p4d, addr, next, altmap, direct);
1130 }
1131
1132 flush_tlb_all();
1133}
1134
1135void __ref vmemmap_free(unsigned long start, unsigned long end,
1136 struct vmem_altmap *altmap)
1137{
1138 remove_pagetable(start, end, false, altmap);
1139}
1140
1141#ifdef CONFIG_MEMORY_HOTREMOVE
1142static void __meminit
1143kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1144{
1145 start = (unsigned long)__va(start);
1146 end = (unsigned long)__va(end);
1147
1148 remove_pagetable(start, end, true, NULL);
1149}
1150
1151int __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
1152{
1153 unsigned long start_pfn = start >> PAGE_SHIFT;
1154 unsigned long nr_pages = size >> PAGE_SHIFT;
1155 struct page *page = pfn_to_page(start_pfn);
1156 struct zone *zone;
1157 int ret;
1158
1159 /* With altmap the first mapped page is offset from @start */
1160 if (altmap)
1161 page += vmem_altmap_offset(altmap);
1162 zone = page_zone(page);
1163 ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
1164 WARN_ON_ONCE(ret);
1165 kernel_physical_mapping_remove(start, start + size);
1166
1167 return ret;
1168}
1169#endif
1170#endif /* CONFIG_MEMORY_HOTPLUG */
1171
1172static struct kcore_list kcore_vsyscall;
1173
1174static void __init register_page_bootmem_info(void)
1175{
1176#ifdef CONFIG_NUMA
1177 int i;
1178
1179 for_each_online_node(i)
1180 register_page_bootmem_info_node(NODE_DATA(i));
1181#endif
1182}
1183
1184void __init mem_init(void)
1185{
1186 pci_iommu_alloc();
1187
1188 /* clear_bss() already clear the empty_zero_page */
1189
1190 /* this will put all memory onto the freelists */
1191 free_all_bootmem();
1192 after_bootmem = 1;
1193 x86_init.hyper.init_after_bootmem();
1194
1195 /*
1196 * Must be done after boot memory is put on freelist, because here we
1197 * might set fields in deferred struct pages that have not yet been
1198 * initialized, and free_all_bootmem() initializes all the reserved
1199 * deferred pages for us.
1200 */
1201 register_page_bootmem_info();
1202
1203 /* Register memory areas for /proc/kcore */
1204 if (get_gate_vma(&init_mm))
1205 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
1206
1207 mem_init_print_info(NULL);
1208}
1209
1210int kernel_set_to_readonly;
1211
1212void set_kernel_text_rw(void)
1213{
1214 unsigned long start = PFN_ALIGN(_text);
1215 unsigned long end = PFN_ALIGN(__stop___ex_table);
1216
1217 if (!kernel_set_to_readonly)
1218 return;
1219
1220 pr_debug("Set kernel text: %lx - %lx for read write\n",
1221 start, end);
1222
1223 /*
1224 * Make the kernel identity mapping for text RW. Kernel text
1225 * mapping will always be RO. Refer to the comment in
1226 * static_protections() in pageattr.c
1227 */
1228 set_memory_rw(start, (end - start) >> PAGE_SHIFT);
1229}
1230
1231void set_kernel_text_ro(void)
1232{
1233 unsigned long start = PFN_ALIGN(_text);
1234 unsigned long end = PFN_ALIGN(__stop___ex_table);
1235
1236 if (!kernel_set_to_readonly)
1237 return;
1238
1239 pr_debug("Set kernel text: %lx - %lx for read only\n",
1240 start, end);
1241
1242 /*
1243 * Set the kernel identity mapping for text RO.
1244 */
1245 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1246}
1247
1248void mark_rodata_ro(void)
1249{
1250 unsigned long start = PFN_ALIGN(_text);
1251 unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1252 unsigned long end = (unsigned long) &__end_rodata_hpage_align;
1253 unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
1254 unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
1255 unsigned long all_end;
1256
1257 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1258 (end - start) >> 10);
1259 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1260
1261 kernel_set_to_readonly = 1;
1262
1263 /*
1264 * The rodata/data/bss/brk section (but not the kernel text!)
1265 * should also be not-executable.
1266 *
1267 * We align all_end to PMD_SIZE because the existing mapping
1268 * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1269 * split the PMD and the reminder between _brk_end and the end
1270 * of the PMD will remain mapped executable.
1271 *
1272 * Any PMD which was setup after the one which covers _brk_end
1273 * has been zapped already via cleanup_highmem().
1274 */
1275 all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1276 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1277
1278#ifdef CONFIG_CPA_DEBUG
1279 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1280 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1281
1282 printk(KERN_INFO "Testing CPA: again\n");
1283 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1284#endif
1285
1286 free_init_pages("unused kernel",
1287 (unsigned long) __va(__pa_symbol(text_end)),
1288 (unsigned long) __va(__pa_symbol(rodata_start)));
1289 free_init_pages("unused kernel",
1290 (unsigned long) __va(__pa_symbol(rodata_end)),
1291 (unsigned long) __va(__pa_symbol(_sdata)));
1292
1293 debug_checkwx();
1294
1295 /*
1296 * Do this after all of the manipulation of the
1297 * kernel text page tables are complete.
1298 */
1299 pti_clone_kernel_text();
1300}
1301
1302int kern_addr_valid(unsigned long addr)
1303{
1304 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1305 pgd_t *pgd;
1306 p4d_t *p4d;
1307 pud_t *pud;
1308 pmd_t *pmd;
1309 pte_t *pte;
1310
1311 if (above != 0 && above != -1UL)
1312 return 0;
1313
1314 pgd = pgd_offset_k(addr);
1315 if (pgd_none(*pgd))
1316 return 0;
1317
1318 p4d = p4d_offset(pgd, addr);
1319 if (p4d_none(*p4d))
1320 return 0;
1321
1322 pud = pud_offset(p4d, addr);
1323 if (pud_none(*pud))
1324 return 0;
1325
1326 if (pud_large(*pud))
1327 return pfn_valid(pud_pfn(*pud));
1328
1329 pmd = pmd_offset(pud, addr);
1330 if (pmd_none(*pmd))
1331 return 0;
1332
1333 if (pmd_large(*pmd))
1334 return pfn_valid(pmd_pfn(*pmd));
1335
1336 pte = pte_offset_kernel(pmd, addr);
1337 if (pte_none(*pte))
1338 return 0;
1339
1340 return pfn_valid(pte_pfn(*pte));
1341}
1342
1343/*
1344 * Block size is the minimum amount of memory which can be hotplugged or
1345 * hotremoved. It must be power of two and must be equal or larger than
1346 * MIN_MEMORY_BLOCK_SIZE.
1347 */
1348#define MAX_BLOCK_SIZE (2UL << 30)
1349
1350/* Amount of ram needed to start using large blocks */
1351#define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30)
1352
1353static unsigned long probe_memory_block_size(void)
1354{
1355 unsigned long boot_mem_end = max_pfn << PAGE_SHIFT;
1356 unsigned long bz;
1357
1358 /* If this is UV system, always set 2G block size */
1359 if (is_uv_system()) {
1360 bz = MAX_BLOCK_SIZE;
1361 goto done;
1362 }
1363
1364 /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */
1365 if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) {
1366 bz = MIN_MEMORY_BLOCK_SIZE;
1367 goto done;
1368 }
1369
1370 /* Find the largest allowed block size that aligns to memory end */
1371 for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) {
1372 if (IS_ALIGNED(boot_mem_end, bz))
1373 break;
1374 }
1375done:
1376 pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1377
1378 return bz;
1379}
1380
1381static unsigned long memory_block_size_probed;
1382unsigned long memory_block_size_bytes(void)
1383{
1384 if (!memory_block_size_probed)
1385 memory_block_size_probed = probe_memory_block_size();
1386
1387 return memory_block_size_probed;
1388}
1389
1390#ifdef CONFIG_SPARSEMEM_VMEMMAP
1391/*
1392 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1393 */
1394static long __meminitdata addr_start, addr_end;
1395static void __meminitdata *p_start, *p_end;
1396static int __meminitdata node_start;
1397
1398static int __meminit vmemmap_populate_hugepages(unsigned long start,
1399 unsigned long end, int node, struct vmem_altmap *altmap)
1400{
1401 unsigned long addr;
1402 unsigned long next;
1403 pgd_t *pgd;
1404 p4d_t *p4d;
1405 pud_t *pud;
1406 pmd_t *pmd;
1407
1408 for (addr = start; addr < end; addr = next) {
1409 next = pmd_addr_end(addr, end);
1410
1411 pgd = vmemmap_pgd_populate(addr, node);
1412 if (!pgd)
1413 return -ENOMEM;
1414
1415 p4d = vmemmap_p4d_populate(pgd, addr, node);
1416 if (!p4d)
1417 return -ENOMEM;
1418
1419 pud = vmemmap_pud_populate(p4d, addr, node);
1420 if (!pud)
1421 return -ENOMEM;
1422
1423 pmd = pmd_offset(pud, addr);
1424 if (pmd_none(*pmd)) {
1425 void *p;
1426
1427 if (altmap)
1428 p = altmap_alloc_block_buf(PMD_SIZE, altmap);
1429 else
1430 p = vmemmap_alloc_block_buf(PMD_SIZE, node);
1431 if (p) {
1432 pte_t entry;
1433
1434 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1435 PAGE_KERNEL_LARGE);
1436 set_pmd(pmd, __pmd(pte_val(entry)));
1437
1438 /* check to see if we have contiguous blocks */
1439 if (p_end != p || node_start != node) {
1440 if (p_start)
1441 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1442 addr_start, addr_end-1, p_start, p_end-1, node_start);
1443 addr_start = addr;
1444 node_start = node;
1445 p_start = p;
1446 }
1447
1448 addr_end = addr + PMD_SIZE;
1449 p_end = p + PMD_SIZE;
1450 continue;
1451 } else if (altmap)
1452 return -ENOMEM; /* no fallback */
1453 } else if (pmd_large(*pmd)) {
1454 vmemmap_verify((pte_t *)pmd, node, addr, next);
1455 continue;
1456 }
1457 if (vmemmap_populate_basepages(addr, next, node))
1458 return -ENOMEM;
1459 }
1460 return 0;
1461}
1462
1463int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1464 struct vmem_altmap *altmap)
1465{
1466 int err;
1467
1468 if (boot_cpu_has(X86_FEATURE_PSE))
1469 err = vmemmap_populate_hugepages(start, end, node, altmap);
1470 else if (altmap) {
1471 pr_err_once("%s: no cpu support for altmap allocations\n",
1472 __func__);
1473 err = -ENOMEM;
1474 } else
1475 err = vmemmap_populate_basepages(start, end, node);
1476 if (!err)
1477 sync_global_pgds(start, end - 1);
1478 return err;
1479}
1480
1481#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1482void register_page_bootmem_memmap(unsigned long section_nr,
1483 struct page *start_page, unsigned long nr_pages)
1484{
1485 unsigned long addr = (unsigned long)start_page;
1486 unsigned long end = (unsigned long)(start_page + nr_pages);
1487 unsigned long next;
1488 pgd_t *pgd;
1489 p4d_t *p4d;
1490 pud_t *pud;
1491 pmd_t *pmd;
1492 unsigned int nr_pmd_pages;
1493 struct page *page;
1494
1495 for (; addr < end; addr = next) {
1496 pte_t *pte = NULL;
1497
1498 pgd = pgd_offset_k(addr);
1499 if (pgd_none(*pgd)) {
1500 next = (addr + PAGE_SIZE) & PAGE_MASK;
1501 continue;
1502 }
1503 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1504
1505 p4d = p4d_offset(pgd, addr);
1506 if (p4d_none(*p4d)) {
1507 next = (addr + PAGE_SIZE) & PAGE_MASK;
1508 continue;
1509 }
1510 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
1511
1512 pud = pud_offset(p4d, addr);
1513 if (pud_none(*pud)) {
1514 next = (addr + PAGE_SIZE) & PAGE_MASK;
1515 continue;
1516 }
1517 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1518
1519 if (!boot_cpu_has(X86_FEATURE_PSE)) {
1520 next = (addr + PAGE_SIZE) & PAGE_MASK;
1521 pmd = pmd_offset(pud, addr);
1522 if (pmd_none(*pmd))
1523 continue;
1524 get_page_bootmem(section_nr, pmd_page(*pmd),
1525 MIX_SECTION_INFO);
1526
1527 pte = pte_offset_kernel(pmd, addr);
1528 if (pte_none(*pte))
1529 continue;
1530 get_page_bootmem(section_nr, pte_page(*pte),
1531 SECTION_INFO);
1532 } else {
1533 next = pmd_addr_end(addr, end);
1534
1535 pmd = pmd_offset(pud, addr);
1536 if (pmd_none(*pmd))
1537 continue;
1538
1539 nr_pmd_pages = 1 << get_order(PMD_SIZE);
1540 page = pmd_page(*pmd);
1541 while (nr_pmd_pages--)
1542 get_page_bootmem(section_nr, page++,
1543 SECTION_INFO);
1544 }
1545 }
1546}
1547#endif
1548
1549void __meminit vmemmap_populate_print_last(void)
1550{
1551 if (p_start) {
1552 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1553 addr_start, addr_end-1, p_start, p_end-1, node_start);
1554 p_start = NULL;
1555 p_end = NULL;
1556 node_start = 0;
1557 }
1558}
1559#endif