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) \
64 static 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
73 DEFINE_POPULATE(p4d_populate, p4d, pud, init)
74 DEFINE_POPULATE(pgd_populate, pgd, p4d, init)
75 DEFINE_POPULATE(pud_populate, pud, pmd, init)
76 DEFINE_POPULATE(pmd_populate_kernel, pmd, pte, init)
77
78 #define DEFINE_ENTRY(type1, type2, init) \
79 static 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
88 DEFINE_ENTRY(p4d, p4d, init)
89 DEFINE_ENTRY(pud, pud, init)
90 DEFINE_ENTRY(pmd, pmd, init)
91 DEFINE_ENTRY(pte, pte, init)
92
93 static 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: */
107 pteval_t __supported_pte_mask __read_mostly = ~0;
108 /* Bits allowed in normal kernel mappings: */
109 pteval_t __default_kernel_pte_mask __read_mostly = ~0;
110 EXPORT_SYMBOL_GPL(__supported_pte_mask);
111 /* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
112 EXPORT_SYMBOL(__default_kernel_pte_mask);
113
114 int 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 */
123 static 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
133 static 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
170 static 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 */
218 static 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 */
230 static __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
249 static 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
261 static 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
273 static 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
285 static 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
296 static 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
310 void 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
318 void 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
325 void 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
343 pmd_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
355 pte_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 */
366 static 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
403 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
404 {
405 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
406 }
407
408 void __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 */
426 void __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 */
453 static unsigned long __meminit
454 phys_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 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
474 E820_TYPE_ACPI))
475 set_pte_init(pte, __pte(0), init);
476 continue;
477 }
478
479 /*
480 * We will re-use the existing mapping.
481 * Xen for example has some special requirements, like mapping
482 * pagetable pages as RO. So assume someone who pre-setup
483 * these mappings are more intelligent.
484 */
485 if (!pte_none(*pte)) {
486 if (!after_bootmem)
487 pages++;
488 continue;
489 }
490
491 if (0)
492 pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr,
493 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
494 pages++;
495 set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init);
496 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
497 }
498
499 update_page_count(PG_LEVEL_4K, pages);
500
501 return paddr_last;
502 }
503
504 /*
505 * Create PMD level page table mapping for physical addresses. The virtual
506 * and physical address have to be aligned at this level.
507 * It returns the last physical address mapped.
508 */
509 static unsigned long __meminit
510 phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
511 unsigned long page_size_mask, pgprot_t prot, bool init)
512 {
513 unsigned long pages = 0, paddr_next;
514 unsigned long paddr_last = paddr_end;
515
516 int i = pmd_index(paddr);
517
518 for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
519 pmd_t *pmd = pmd_page + pmd_index(paddr);
520 pte_t *pte;
521 pgprot_t new_prot = prot;
522
523 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
524 if (paddr >= paddr_end) {
525 if (!after_bootmem &&
526 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
527 E820_TYPE_RAM) &&
528 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
529 E820_TYPE_RESERVED_KERN) &&
530 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
531 E820_TYPE_ACPI))
532 set_pmd_init(pmd, __pmd(0), init);
533 continue;
534 }
535
536 if (!pmd_none(*pmd)) {
537 if (!pmd_leaf(*pmd)) {
538 spin_lock(&init_mm.page_table_lock);
539 pte = (pte_t *)pmd_page_vaddr(*pmd);
540 paddr_last = phys_pte_init(pte, paddr,
541 paddr_end, prot,
542 init);
543 spin_unlock(&init_mm.page_table_lock);
544 continue;
545 }
546 /*
547 * If we are ok with PG_LEVEL_2M mapping, then we will
548 * use the existing mapping,
549 *
550 * Otherwise, we will split the large page mapping but
551 * use the same existing protection bits except for
552 * large page, so that we don't violate Intel's TLB
553 * Application note (317080) which says, while changing
554 * the page sizes, new and old translations should
555 * not differ with respect to page frame and
556 * attributes.
557 */
558 if (page_size_mask & (1 << PG_LEVEL_2M)) {
559 if (!after_bootmem)
560 pages++;
561 paddr_last = paddr_next;
562 continue;
563 }
564 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
565 }
566
567 if (page_size_mask & (1<<PG_LEVEL_2M)) {
568 pages++;
569 spin_lock(&init_mm.page_table_lock);
570 set_pmd_init(pmd,
571 pfn_pmd(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
572 init);
573 spin_unlock(&init_mm.page_table_lock);
574 paddr_last = paddr_next;
575 continue;
576 }
577
578 pte = alloc_low_page();
579 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init);
580
581 spin_lock(&init_mm.page_table_lock);
582 pmd_populate_kernel_init(&init_mm, pmd, pte, init);
583 spin_unlock(&init_mm.page_table_lock);
584 }
585 update_page_count(PG_LEVEL_2M, pages);
586 return paddr_last;
587 }
588
589 /*
590 * Create PUD level page table mapping for physical addresses. The virtual
591 * and physical address do not have to be aligned at this level. KASLR can
592 * randomize virtual addresses up to this level.
593 * It returns the last physical address mapped.
594 */
595 static unsigned long __meminit
596 phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
597 unsigned long page_size_mask, pgprot_t _prot, bool init)
598 {
599 unsigned long pages = 0, paddr_next;
600 unsigned long paddr_last = paddr_end;
601 unsigned long vaddr = (unsigned long)__va(paddr);
602 int i = pud_index(vaddr);
603
604 for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
605 pud_t *pud;
606 pmd_t *pmd;
607 pgprot_t prot = _prot;
608
609 vaddr = (unsigned long)__va(paddr);
610 pud = pud_page + pud_index(vaddr);
611 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
612
613 if (paddr >= paddr_end) {
614 if (!after_bootmem &&
615 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
616 E820_TYPE_RAM) &&
617 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
618 E820_TYPE_RESERVED_KERN) &&
619 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
620 E820_TYPE_ACPI))
621 set_pud_init(pud, __pud(0), init);
622 continue;
623 }
624
625 if (!pud_none(*pud)) {
626 if (!pud_leaf(*pud)) {
627 pmd = pmd_offset(pud, 0);
628 paddr_last = phys_pmd_init(pmd, paddr,
629 paddr_end,
630 page_size_mask,
631 prot, init);
632 continue;
633 }
634 /*
635 * If we are ok with PG_LEVEL_1G mapping, then we will
636 * use the existing mapping.
637 *
638 * Otherwise, we will split the gbpage mapping but use
639 * the same existing protection bits except for large
640 * page, so that we don't violate Intel's TLB
641 * Application note (317080) which says, while changing
642 * the page sizes, new and old translations should
643 * not differ with respect to page frame and
644 * attributes.
645 */
646 if (page_size_mask & (1 << PG_LEVEL_1G)) {
647 if (!after_bootmem)
648 pages++;
649 paddr_last = paddr_next;
650 continue;
651 }
652 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
653 }
654
655 if (page_size_mask & (1<<PG_LEVEL_1G)) {
656 pages++;
657 spin_lock(&init_mm.page_table_lock);
658 set_pud_init(pud,
659 pfn_pud(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
660 init);
661 spin_unlock(&init_mm.page_table_lock);
662 paddr_last = paddr_next;
663 continue;
664 }
665
666 pmd = alloc_low_page();
667 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
668 page_size_mask, prot, init);
669
670 spin_lock(&init_mm.page_table_lock);
671 pud_populate_init(&init_mm, pud, pmd, init);
672 spin_unlock(&init_mm.page_table_lock);
673 }
674
675 update_page_count(PG_LEVEL_1G, pages);
676
677 return paddr_last;
678 }
679
680 static unsigned long __meminit
681 phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
682 unsigned long page_size_mask, pgprot_t prot, bool init)
683 {
684 unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last;
685
686 paddr_last = paddr_end;
687 vaddr = (unsigned long)__va(paddr);
688 vaddr_end = (unsigned long)__va(paddr_end);
689
690 if (!pgtable_l5_enabled())
691 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end,
692 page_size_mask, prot, init);
693
694 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
695 p4d_t *p4d = p4d_page + p4d_index(vaddr);
696 pud_t *pud;
697
698 vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE;
699 paddr = __pa(vaddr);
700
701 if (paddr >= paddr_end) {
702 paddr_next = __pa(vaddr_next);
703 if (!after_bootmem &&
704 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
705 E820_TYPE_RAM) &&
706 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
707 E820_TYPE_RESERVED_KERN) &&
708 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
709 E820_TYPE_ACPI))
710 set_p4d_init(p4d, __p4d(0), init);
711 continue;
712 }
713
714 if (!p4d_none(*p4d)) {
715 pud = pud_offset(p4d, 0);
716 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
717 page_size_mask, prot, init);
718 continue;
719 }
720
721 pud = alloc_low_page();
722 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
723 page_size_mask, prot, init);
724
725 spin_lock(&init_mm.page_table_lock);
726 p4d_populate_init(&init_mm, p4d, pud, init);
727 spin_unlock(&init_mm.page_table_lock);
728 }
729
730 return paddr_last;
731 }
732
733 static unsigned long __meminit
734 __kernel_physical_mapping_init(unsigned long paddr_start,
735 unsigned long paddr_end,
736 unsigned long page_size_mask,
737 pgprot_t prot, bool init)
738 {
739 bool pgd_changed = false;
740 unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
741
742 paddr_last = paddr_end;
743 vaddr = (unsigned long)__va(paddr_start);
744 vaddr_end = (unsigned long)__va(paddr_end);
745 vaddr_start = vaddr;
746
747 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
748 pgd_t *pgd = pgd_offset_k(vaddr);
749 p4d_t *p4d;
750
751 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
752
753 if (pgd_val(*pgd)) {
754 p4d = (p4d_t *)pgd_page_vaddr(*pgd);
755 paddr_last = phys_p4d_init(p4d, __pa(vaddr),
756 __pa(vaddr_end),
757 page_size_mask,
758 prot, init);
759 continue;
760 }
761
762 p4d = alloc_low_page();
763 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
764 page_size_mask, prot, init);
765
766 spin_lock(&init_mm.page_table_lock);
767 if (pgtable_l5_enabled())
768 pgd_populate_init(&init_mm, pgd, p4d, init);
769 else
770 p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr),
771 (pud_t *) p4d, init);
772
773 spin_unlock(&init_mm.page_table_lock);
774 pgd_changed = true;
775 }
776
777 if (pgd_changed)
778 sync_global_pgds(vaddr_start, vaddr_end - 1);
779
780 return paddr_last;
781 }
782
783
784 /*
785 * Create page table mapping for the physical memory for specific physical
786 * addresses. Note that it can only be used to populate non-present entries.
787 * The virtual and physical addresses have to be aligned on PMD level
788 * down. It returns the last physical address mapped.
789 */
790 unsigned long __meminit
791 kernel_physical_mapping_init(unsigned long paddr_start,
792 unsigned long paddr_end,
793 unsigned long page_size_mask, pgprot_t prot)
794 {
795 return __kernel_physical_mapping_init(paddr_start, paddr_end,
796 page_size_mask, prot, true);
797 }
798
799 /*
800 * This function is similar to kernel_physical_mapping_init() above with the
801 * exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe()
802 * when updating the mapping. The caller is responsible to flush the TLBs after
803 * the function returns.
804 */
805 unsigned long __meminit
806 kernel_physical_mapping_change(unsigned long paddr_start,
807 unsigned long paddr_end,
808 unsigned long page_size_mask)
809 {
810 return __kernel_physical_mapping_init(paddr_start, paddr_end,
811 page_size_mask, PAGE_KERNEL,
812 false);
813 }
814
815 #ifndef CONFIG_NUMA
816 void __init initmem_init(void)
817 {
818 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
819 }
820 #endif
821
822 void __init paging_init(void)
823 {
824 sparse_init();
825
826 /*
827 * clear the default setting with node 0
828 * note: don't use nodes_clear here, that is really clearing when
829 * numa support is not compiled in, and later node_set_state
830 * will not set it back.
831 */
832 node_clear_state(0, N_MEMORY);
833 node_clear_state(0, N_NORMAL_MEMORY);
834
835 zone_sizes_init();
836 }
837
838 #ifdef CONFIG_SPARSEMEM_VMEMMAP
839 #define PAGE_UNUSED 0xFD
840
841 /*
842 * The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges
843 * from unused_pmd_start to next PMD_SIZE boundary.
844 */
845 static unsigned long unused_pmd_start __meminitdata;
846
847 static void __meminit vmemmap_flush_unused_pmd(void)
848 {
849 if (!unused_pmd_start)
850 return;
851 /*
852 * Clears (unused_pmd_start, PMD_END]
853 */
854 memset((void *)unused_pmd_start, PAGE_UNUSED,
855 ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start);
856 unused_pmd_start = 0;
857 }
858
859 #ifdef CONFIG_MEMORY_HOTPLUG
860 /* Returns true if the PMD is completely unused and thus it can be freed */
861 static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end)
862 {
863 unsigned long start = ALIGN_DOWN(addr, PMD_SIZE);
864
865 /*
866 * Flush the unused range cache to ensure that memchr_inv() will work
867 * for the whole range.
868 */
869 vmemmap_flush_unused_pmd();
870 memset((void *)addr, PAGE_UNUSED, end - addr);
871
872 return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE);
873 }
874 #endif
875
876 static void __meminit __vmemmap_use_sub_pmd(unsigned long start)
877 {
878 /*
879 * As we expect to add in the same granularity as we remove, it's
880 * sufficient to mark only some piece used to block the memmap page from
881 * getting removed when removing some other adjacent memmap (just in
882 * case the first memmap never gets initialized e.g., because the memory
883 * block never gets onlined).
884 */
885 memset((void *)start, 0, sizeof(struct page));
886 }
887
888 static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end)
889 {
890 /*
891 * We only optimize if the new used range directly follows the
892 * previously unused range (esp., when populating consecutive sections).
893 */
894 if (unused_pmd_start == start) {
895 if (likely(IS_ALIGNED(end, PMD_SIZE)))
896 unused_pmd_start = 0;
897 else
898 unused_pmd_start = end;
899 return;
900 }
901
902 /*
903 * If the range does not contiguously follows previous one, make sure
904 * to mark the unused range of the previous one so it can be removed.
905 */
906 vmemmap_flush_unused_pmd();
907 __vmemmap_use_sub_pmd(start);
908 }
909
910
911 static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
912 {
913 const unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
914
915 vmemmap_flush_unused_pmd();
916
917 /*
918 * Could be our memmap page is filled with PAGE_UNUSED already from a
919 * previous remove. Make sure to reset it.
920 */
921 __vmemmap_use_sub_pmd(start);
922
923 /*
924 * Mark with PAGE_UNUSED the unused parts of the new memmap range
925 */
926 if (!IS_ALIGNED(start, PMD_SIZE))
927 memset((void *)page, PAGE_UNUSED, start - page);
928
929 /*
930 * We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of
931 * consecutive sections. Remember for the last added PMD where the
932 * unused range begins.
933 */
934 if (!IS_ALIGNED(end, PMD_SIZE))
935 unused_pmd_start = end;
936 }
937 #endif
938
939 /*
940 * Memory hotplug specific functions
941 */
942 #ifdef CONFIG_MEMORY_HOTPLUG
943 /*
944 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
945 * updating.
946 */
947 static void update_end_of_memory_vars(u64 start, u64 size)
948 {
949 unsigned long end_pfn = PFN_UP(start + size);
950
951 if (end_pfn > max_pfn) {
952 max_pfn = end_pfn;
953 max_low_pfn = end_pfn;
954 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
955 }
956 }
957
958 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
959 struct mhp_params *params)
960 {
961 unsigned long end = ((start_pfn + nr_pages) << PAGE_SHIFT) - 1;
962 int ret;
963
964 if (WARN_ON_ONCE(end > PHYSMEM_END))
965 return -ERANGE;
966
967 ret = __add_pages(nid, start_pfn, nr_pages, params);
968 WARN_ON_ONCE(ret);
969
970 /* update max_pfn, max_low_pfn and high_memory */
971 update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
972 nr_pages << PAGE_SHIFT);
973
974 return ret;
975 }
976
977 int arch_add_memory(int nid, u64 start, u64 size,
978 struct mhp_params *params)
979 {
980 unsigned long start_pfn = start >> PAGE_SHIFT;
981 unsigned long nr_pages = size >> PAGE_SHIFT;
982
983 init_memory_mapping(start, start + size, params->pgprot);
984
985 return add_pages(nid, start_pfn, nr_pages, params);
986 }
987
988 static void __meminit free_pagetable(struct page *page, int order)
989 {
990 unsigned long magic;
991 unsigned int nr_pages = 1 << order;
992
993 /* bootmem page has reserved flag */
994 if (PageReserved(page)) {
995 magic = page->index;
996 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
997 while (nr_pages--)
998 put_page_bootmem(page++);
999 } else
1000 while (nr_pages--)
1001 free_reserved_page(page++);
1002 } else
1003 free_pages((unsigned long)page_address(page), order);
1004 }
1005
1006 static void __meminit free_hugepage_table(struct page *page,
1007 struct vmem_altmap *altmap)
1008 {
1009 if (altmap)
1010 vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE);
1011 else
1012 free_pagetable(page, get_order(PMD_SIZE));
1013 }
1014
1015 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
1016 {
1017 pte_t *pte;
1018 int i;
1019
1020 for (i = 0; i < PTRS_PER_PTE; i++) {
1021 pte = pte_start + i;
1022 if (!pte_none(*pte))
1023 return;
1024 }
1025
1026 /* free a pte table */
1027 free_pagetable(pmd_page(*pmd), 0);
1028 spin_lock(&init_mm.page_table_lock);
1029 pmd_clear(pmd);
1030 spin_unlock(&init_mm.page_table_lock);
1031 }
1032
1033 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
1034 {
1035 pmd_t *pmd;
1036 int i;
1037
1038 for (i = 0; i < PTRS_PER_PMD; i++) {
1039 pmd = pmd_start + i;
1040 if (!pmd_none(*pmd))
1041 return;
1042 }
1043
1044 /* free a pmd table */
1045 free_pagetable(pud_page(*pud), 0);
1046 spin_lock(&init_mm.page_table_lock);
1047 pud_clear(pud);
1048 spin_unlock(&init_mm.page_table_lock);
1049 }
1050
1051 static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
1052 {
1053 pud_t *pud;
1054 int i;
1055
1056 for (i = 0; i < PTRS_PER_PUD; i++) {
1057 pud = pud_start + i;
1058 if (!pud_none(*pud))
1059 return;
1060 }
1061
1062 /* free a pud table */
1063 free_pagetable(p4d_page(*p4d), 0);
1064 spin_lock(&init_mm.page_table_lock);
1065 p4d_clear(p4d);
1066 spin_unlock(&init_mm.page_table_lock);
1067 }
1068
1069 static void __meminit
1070 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
1071 bool direct)
1072 {
1073 unsigned long next, pages = 0;
1074 pte_t *pte;
1075 phys_addr_t phys_addr;
1076
1077 pte = pte_start + pte_index(addr);
1078 for (; addr < end; addr = next, pte++) {
1079 next = (addr + PAGE_SIZE) & PAGE_MASK;
1080 if (next > end)
1081 next = end;
1082
1083 if (!pte_present(*pte))
1084 continue;
1085
1086 /*
1087 * We mapped [0,1G) memory as identity mapping when
1088 * initializing, in arch/x86/kernel/head_64.S. These
1089 * pagetables cannot be removed.
1090 */
1091 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
1092 if (phys_addr < (phys_addr_t)0x40000000)
1093 return;
1094
1095 if (!direct)
1096 free_pagetable(pte_page(*pte), 0);
1097
1098 spin_lock(&init_mm.page_table_lock);
1099 pte_clear(&init_mm, addr, pte);
1100 spin_unlock(&init_mm.page_table_lock);
1101
1102 /* For non-direct mapping, pages means nothing. */
1103 pages++;
1104 }
1105
1106 /* Call free_pte_table() in remove_pmd_table(). */
1107 flush_tlb_all();
1108 if (direct)
1109 update_page_count(PG_LEVEL_4K, -pages);
1110 }
1111
1112 static void __meminit
1113 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
1114 bool direct, struct vmem_altmap *altmap)
1115 {
1116 unsigned long next, pages = 0;
1117 pte_t *pte_base;
1118 pmd_t *pmd;
1119
1120 pmd = pmd_start + pmd_index(addr);
1121 for (; addr < end; addr = next, pmd++) {
1122 next = pmd_addr_end(addr, end);
1123
1124 if (!pmd_present(*pmd))
1125 continue;
1126
1127 if (pmd_leaf(*pmd)) {
1128 if (IS_ALIGNED(addr, PMD_SIZE) &&
1129 IS_ALIGNED(next, PMD_SIZE)) {
1130 if (!direct)
1131 free_hugepage_table(pmd_page(*pmd),
1132 altmap);
1133
1134 spin_lock(&init_mm.page_table_lock);
1135 pmd_clear(pmd);
1136 spin_unlock(&init_mm.page_table_lock);
1137 pages++;
1138 }
1139 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1140 else if (vmemmap_pmd_is_unused(addr, next)) {
1141 free_hugepage_table(pmd_page(*pmd),
1142 altmap);
1143 spin_lock(&init_mm.page_table_lock);
1144 pmd_clear(pmd);
1145 spin_unlock(&init_mm.page_table_lock);
1146 }
1147 #endif
1148 continue;
1149 }
1150
1151 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
1152 remove_pte_table(pte_base, addr, next, direct);
1153 free_pte_table(pte_base, pmd);
1154 }
1155
1156 /* Call free_pmd_table() in remove_pud_table(). */
1157 if (direct)
1158 update_page_count(PG_LEVEL_2M, -pages);
1159 }
1160
1161 static void __meminit
1162 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
1163 struct vmem_altmap *altmap, bool direct)
1164 {
1165 unsigned long next, pages = 0;
1166 pmd_t *pmd_base;
1167 pud_t *pud;
1168
1169 pud = pud_start + pud_index(addr);
1170 for (; addr < end; addr = next, pud++) {
1171 next = pud_addr_end(addr, end);
1172
1173 if (!pud_present(*pud))
1174 continue;
1175
1176 if (pud_leaf(*pud) &&
1177 IS_ALIGNED(addr, PUD_SIZE) &&
1178 IS_ALIGNED(next, PUD_SIZE)) {
1179 spin_lock(&init_mm.page_table_lock);
1180 pud_clear(pud);
1181 spin_unlock(&init_mm.page_table_lock);
1182 pages++;
1183 continue;
1184 }
1185
1186 pmd_base = pmd_offset(pud, 0);
1187 remove_pmd_table(pmd_base, addr, next, direct, altmap);
1188 free_pmd_table(pmd_base, pud);
1189 }
1190
1191 if (direct)
1192 update_page_count(PG_LEVEL_1G, -pages);
1193 }
1194
1195 static void __meminit
1196 remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
1197 struct vmem_altmap *altmap, bool direct)
1198 {
1199 unsigned long next, pages = 0;
1200 pud_t *pud_base;
1201 p4d_t *p4d;
1202
1203 p4d = p4d_start + p4d_index(addr);
1204 for (; addr < end; addr = next, p4d++) {
1205 next = p4d_addr_end(addr, end);
1206
1207 if (!p4d_present(*p4d))
1208 continue;
1209
1210 BUILD_BUG_ON(p4d_leaf(*p4d));
1211
1212 pud_base = pud_offset(p4d, 0);
1213 remove_pud_table(pud_base, addr, next, altmap, direct);
1214 /*
1215 * For 4-level page tables we do not want to free PUDs, but in the
1216 * 5-level case we should free them. This code will have to change
1217 * to adapt for boot-time switching between 4 and 5 level page tables.
1218 */
1219 if (pgtable_l5_enabled())
1220 free_pud_table(pud_base, p4d);
1221 }
1222
1223 if (direct)
1224 update_page_count(PG_LEVEL_512G, -pages);
1225 }
1226
1227 /* start and end are both virtual address. */
1228 static void __meminit
1229 remove_pagetable(unsigned long start, unsigned long end, bool direct,
1230 struct vmem_altmap *altmap)
1231 {
1232 unsigned long next;
1233 unsigned long addr;
1234 pgd_t *pgd;
1235 p4d_t *p4d;
1236
1237 for (addr = start; addr < end; addr = next) {
1238 next = pgd_addr_end(addr, end);
1239
1240 pgd = pgd_offset_k(addr);
1241 if (!pgd_present(*pgd))
1242 continue;
1243
1244 p4d = p4d_offset(pgd, 0);
1245 remove_p4d_table(p4d, addr, next, altmap, direct);
1246 }
1247
1248 flush_tlb_all();
1249 }
1250
1251 void __ref vmemmap_free(unsigned long start, unsigned long end,
1252 struct vmem_altmap *altmap)
1253 {
1254 VM_BUG_ON(!PAGE_ALIGNED(start));
1255 VM_BUG_ON(!PAGE_ALIGNED(end));
1256
1257 remove_pagetable(start, end, false, altmap);
1258 }
1259
1260 static void __meminit
1261 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1262 {
1263 start = (unsigned long)__va(start);
1264 end = (unsigned long)__va(end);
1265
1266 remove_pagetable(start, end, true, NULL);
1267 }
1268
1269 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
1270 {
1271 unsigned long start_pfn = start >> PAGE_SHIFT;
1272 unsigned long nr_pages = size >> PAGE_SHIFT;
1273
1274 __remove_pages(start_pfn, nr_pages, altmap);
1275 kernel_physical_mapping_remove(start, start + size);
1276 }
1277 #endif /* CONFIG_MEMORY_HOTPLUG */
1278
1279 static struct kcore_list kcore_vsyscall;
1280
1281 static void __init register_page_bootmem_info(void)
1282 {
1283 #if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP)
1284 int i;
1285
1286 for_each_online_node(i)
1287 register_page_bootmem_info_node(NODE_DATA(i));
1288 #endif
1289 }
1290
1291 /*
1292 * Pre-allocates page-table pages for the vmalloc area in the kernel page-table.
1293 * Only the level which needs to be synchronized between all page-tables is
1294 * allocated because the synchronization can be expensive.
1295 */
1296 static void __init preallocate_vmalloc_pages(void)
1297 {
1298 unsigned long addr;
1299 const char *lvl;
1300
1301 for (addr = VMALLOC_START; addr <= VMEMORY_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1302 pgd_t *pgd = pgd_offset_k(addr);
1303 p4d_t *p4d;
1304 pud_t *pud;
1305
1306 lvl = "p4d";
1307 p4d = p4d_alloc(&init_mm, pgd, addr);
1308 if (!p4d)
1309 goto failed;
1310
1311 if (pgtable_l5_enabled())
1312 continue;
1313
1314 /*
1315 * The goal here is to allocate all possibly required
1316 * hardware page tables pointed to by the top hardware
1317 * level.
1318 *
1319 * On 4-level systems, the P4D layer is folded away and
1320 * the above code does no preallocation. Below, go down
1321 * to the pud _software_ level to ensure the second
1322 * hardware level is allocated on 4-level systems too.
1323 */
1324 lvl = "pud";
1325 pud = pud_alloc(&init_mm, p4d, addr);
1326 if (!pud)
1327 goto failed;
1328 }
1329
1330 return;
1331
1332 failed:
1333
1334 /*
1335 * The pages have to be there now or they will be missing in
1336 * process page-tables later.
1337 */
1338 panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl);
1339 }
1340
1341 void __init mem_init(void)
1342 {
1343 pci_iommu_alloc();
1344
1345 /* clear_bss() already clear the empty_zero_page */
1346
1347 /* this will put all memory onto the freelists */
1348 memblock_free_all();
1349 after_bootmem = 1;
1350 x86_init.hyper.init_after_bootmem();
1351
1352 /*
1353 * Must be done after boot memory is put on freelist, because here we
1354 * might set fields in deferred struct pages that have not yet been
1355 * initialized, and memblock_free_all() initializes all the reserved
1356 * deferred pages for us.
1357 */
1358 register_page_bootmem_info();
1359
1360 /* Register memory areas for /proc/kcore */
1361 if (get_gate_vma(&init_mm))
1362 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
1363
1364 preallocate_vmalloc_pages();
1365 }
1366
1367 int kernel_set_to_readonly;
1368
1369 void mark_rodata_ro(void)
1370 {
1371 unsigned long start = PFN_ALIGN(_text);
1372 unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1373 unsigned long end = (unsigned long)__end_rodata_hpage_align;
1374 unsigned long text_end = PFN_ALIGN(_etext);
1375 unsigned long rodata_end = PFN_ALIGN(__end_rodata);
1376 unsigned long all_end;
1377
1378 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1379 (end - start) >> 10);
1380 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1381
1382 kernel_set_to_readonly = 1;
1383
1384 /*
1385 * The rodata/data/bss/brk section (but not the kernel text!)
1386 * should also be not-executable.
1387 *
1388 * We align all_end to PMD_SIZE because the existing mapping
1389 * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1390 * split the PMD and the reminder between _brk_end and the end
1391 * of the PMD will remain mapped executable.
1392 *
1393 * Any PMD which was setup after the one which covers _brk_end
1394 * has been zapped already via cleanup_highmem().
1395 */
1396 all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1397 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1398
1399 set_ftrace_ops_ro();
1400
1401 #ifdef CONFIG_CPA_DEBUG
1402 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1403 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1404
1405 printk(KERN_INFO "Testing CPA: again\n");
1406 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1407 #endif
1408
1409 free_kernel_image_pages("unused kernel image (text/rodata gap)",
1410 (void *)text_end, (void *)rodata_start);
1411 free_kernel_image_pages("unused kernel image (rodata/data gap)",
1412 (void *)rodata_end, (void *)_sdata);
1413 }
1414
1415 /*
1416 * Block size is the minimum amount of memory which can be hotplugged or
1417 * hotremoved. It must be power of two and must be equal or larger than
1418 * MIN_MEMORY_BLOCK_SIZE.
1419 */
1420 #define MAX_BLOCK_SIZE (2UL << 30)
1421
1422 /* Amount of ram needed to start using large blocks */
1423 #define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30)
1424
1425 /* Adjustable memory block size */
1426 static unsigned long set_memory_block_size;
1427 int __init set_memory_block_size_order(unsigned int order)
1428 {
1429 unsigned long size = 1UL << order;
1430
1431 if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE)
1432 return -EINVAL;
1433
1434 set_memory_block_size = size;
1435 return 0;
1436 }
1437
1438 static unsigned long probe_memory_block_size(void)
1439 {
1440 unsigned long boot_mem_end = max_pfn << PAGE_SHIFT;
1441 unsigned long bz;
1442
1443 /* If memory block size has been set, then use it */
1444 bz = set_memory_block_size;
1445 if (bz)
1446 goto done;
1447
1448 /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */
1449 if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) {
1450 bz = MIN_MEMORY_BLOCK_SIZE;
1451 goto done;
1452 }
1453
1454 /*
1455 * Use max block size to minimize overhead on bare metal, where
1456 * alignment for memory hotplug isn't a concern.
1457 */
1458 if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
1459 bz = MAX_BLOCK_SIZE;
1460 goto done;
1461 }
1462
1463 /* Find the largest allowed block size that aligns to memory end */
1464 for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) {
1465 if (IS_ALIGNED(boot_mem_end, bz))
1466 break;
1467 }
1468 done:
1469 pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1470
1471 return bz;
1472 }
1473
1474 static unsigned long memory_block_size_probed;
1475 unsigned long memory_block_size_bytes(void)
1476 {
1477 if (!memory_block_size_probed)
1478 memory_block_size_probed = probe_memory_block_size();
1479
1480 return memory_block_size_probed;
1481 }
1482
1483 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1484 /*
1485 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1486 */
1487 static long __meminitdata addr_start, addr_end;
1488 static void __meminitdata *p_start, *p_end;
1489 static int __meminitdata node_start;
1490
1491 void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
1492 unsigned long addr, unsigned long next)
1493 {
1494 pte_t entry;
1495
1496 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1497 PAGE_KERNEL_LARGE);
1498 set_pmd(pmd, __pmd(pte_val(entry)));
1499
1500 /* check to see if we have contiguous blocks */
1501 if (p_end != p || node_start != node) {
1502 if (p_start)
1503 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1504 addr_start, addr_end-1, p_start, p_end-1, node_start);
1505 addr_start = addr;
1506 node_start = node;
1507 p_start = p;
1508 }
1509
1510 addr_end = addr + PMD_SIZE;
1511 p_end = p + PMD_SIZE;
1512
1513 if (!IS_ALIGNED(addr, PMD_SIZE) ||
1514 !IS_ALIGNED(next, PMD_SIZE))
1515 vmemmap_use_new_sub_pmd(addr, next);
1516 }
1517
1518 int __meminit vmemmap_check_pmd(pmd_t *pmd, int node,
1519 unsigned long addr, unsigned long next)
1520 {
1521 int large = pmd_leaf(*pmd);
1522
1523 if (pmd_leaf(*pmd)) {
1524 vmemmap_verify((pte_t *)pmd, node, addr, next);
1525 vmemmap_use_sub_pmd(addr, next);
1526 }
1527
1528 return large;
1529 }
1530
1531 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1532 struct vmem_altmap *altmap)
1533 {
1534 int err;
1535
1536 VM_BUG_ON(!PAGE_ALIGNED(start));
1537 VM_BUG_ON(!PAGE_ALIGNED(end));
1538
1539 if (end - start < PAGES_PER_SECTION * sizeof(struct page))
1540 err = vmemmap_populate_basepages(start, end, node, NULL);
1541 else if (boot_cpu_has(X86_FEATURE_PSE))
1542 err = vmemmap_populate_hugepages(start, end, node, altmap);
1543 else if (altmap) {
1544 pr_err_once("%s: no cpu support for altmap allocations\n",
1545 __func__);
1546 err = -ENOMEM;
1547 } else
1548 err = vmemmap_populate_basepages(start, end, node, NULL);
1549 if (!err)
1550 sync_global_pgds(start, end - 1);
1551 return err;
1552 }
1553
1554 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
1555 void register_page_bootmem_memmap(unsigned long section_nr,
1556 struct page *start_page, unsigned long nr_pages)
1557 {
1558 unsigned long addr = (unsigned long)start_page;
1559 unsigned long end = (unsigned long)(start_page + nr_pages);
1560 unsigned long next;
1561 pgd_t *pgd;
1562 p4d_t *p4d;
1563 pud_t *pud;
1564 pmd_t *pmd;
1565 unsigned int nr_pmd_pages;
1566 struct page *page;
1567
1568 for (; addr < end; addr = next) {
1569 pte_t *pte = NULL;
1570
1571 pgd = pgd_offset_k(addr);
1572 if (pgd_none(*pgd)) {
1573 next = (addr + PAGE_SIZE) & PAGE_MASK;
1574 continue;
1575 }
1576 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1577
1578 p4d = p4d_offset(pgd, addr);
1579 if (p4d_none(*p4d)) {
1580 next = (addr + PAGE_SIZE) & PAGE_MASK;
1581 continue;
1582 }
1583 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
1584
1585 pud = pud_offset(p4d, addr);
1586 if (pud_none(*pud)) {
1587 next = (addr + PAGE_SIZE) & PAGE_MASK;
1588 continue;
1589 }
1590 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1591
1592 if (!boot_cpu_has(X86_FEATURE_PSE)) {
1593 next = (addr + PAGE_SIZE) & PAGE_MASK;
1594 pmd = pmd_offset(pud, addr);
1595 if (pmd_none(*pmd))
1596 continue;
1597 get_page_bootmem(section_nr, pmd_page(*pmd),
1598 MIX_SECTION_INFO);
1599
1600 pte = pte_offset_kernel(pmd, addr);
1601 if (pte_none(*pte))
1602 continue;
1603 get_page_bootmem(section_nr, pte_page(*pte),
1604 SECTION_INFO);
1605 } else {
1606 next = pmd_addr_end(addr, end);
1607
1608 pmd = pmd_offset(pud, addr);
1609 if (pmd_none(*pmd))
1610 continue;
1611
1612 nr_pmd_pages = 1 << get_order(PMD_SIZE);
1613 page = pmd_page(*pmd);
1614 while (nr_pmd_pages--)
1615 get_page_bootmem(section_nr, page++,
1616 SECTION_INFO);
1617 }
1618 }
1619 }
1620 #endif
1621
1622 void __meminit vmemmap_populate_print_last(void)
1623 {
1624 if (p_start) {
1625 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1626 addr_start, addr_end-1, p_start, p_end-1, node_start);
1627 p_start = NULL;
1628 p_end = NULL;
1629 node_start = 0;
1630 }
1631 }
1632 #endif
1633
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