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 #include <linux/execmem.h>
38
39 #include <asm/processor.h>
40 #include <asm/bios_ebda.h>
41 #include <linux/uaccess.h>
42 #include <asm/pgalloc.h>
43 #include <asm/dma.h>
44 #include <asm/fixmap.h>
45 #include <asm/e820/api.h>
46 #include <asm/apic.h>
47 #include <asm/tlb.h>
48 #include <asm/mmu_context.h>
49 #include <asm/proto.h>
50 #include <asm/smp.h>
51 #include <asm/sections.h>
52 #include <asm/kdebug.h>
53 #include <asm/numa.h>
54 #include <asm/set_memory.h>
55 #include <asm/init.h>
56 #include <asm/uv/uv.h>
57 #include <asm/setup.h>
58 #include <asm/ftrace.h>
59
60 #include "mm_internal.h"
61
62 #include "ident_map.c"
63
64 #define DEFINE_POPULATE(fname, type1, type2, init) \
65 static inline void fname##_init(struct mm_struct *mm, \
66 type1##_t *arg1, type2##_t *arg2, bool init) \
67 { \
68 if (init) \
69 fname##_safe(mm, arg1, arg2); \
70 else \
71 fname(mm, arg1, arg2); \
72 }
73
DEFINE_POPULATE(p4d_populate,p4d,pud,init)74 DEFINE_POPULATE(p4d_populate, p4d, pud, init)
75 DEFINE_POPULATE(pgd_populate, pgd, p4d, init)
76 DEFINE_POPULATE(pud_populate, pud, pmd, init)
77 DEFINE_POPULATE(pmd_populate_kernel, pmd, pte, init)
78
79 #define DEFINE_ENTRY(type1, type2, init) \
80 static inline void set_##type1##_init(type1##_t *arg1, \
81 type2##_t arg2, bool init) \
82 { \
83 if (init) \
84 set_##type1##_safe(arg1, arg2); \
85 else \
86 set_##type1(arg1, arg2); \
87 }
88
89 DEFINE_ENTRY(p4d, p4d, init)
90 DEFINE_ENTRY(pud, pud, init)
91 DEFINE_ENTRY(pmd, pmd, init)
92 DEFINE_ENTRY(pte, pte, init)
93
94 static inline pgprot_t prot_sethuge(pgprot_t prot)
95 {
96 WARN_ON_ONCE(pgprot_val(prot) & _PAGE_PAT);
97
98 return __pgprot(pgprot_val(prot) | _PAGE_PSE);
99 }
100
101 /*
102 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
103 * physical space so we can cache the place of the first one and move
104 * around without checking the pgd every time.
105 */
106
107 /* Bits supported by the hardware: */
108 pteval_t __supported_pte_mask __read_mostly = ~0;
109 /* Bits allowed in normal kernel mappings: */
110 pteval_t __default_kernel_pte_mask __read_mostly = ~0;
111 EXPORT_SYMBOL_GPL(__supported_pte_mask);
112 /* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
113 EXPORT_SYMBOL(__default_kernel_pte_mask);
114
115 int force_personality32;
116
117 /*
118 * noexec32=on|off
119 * Control non executable heap for 32bit processes.
120 *
121 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
122 * off PROT_READ implies PROT_EXEC
123 */
nonx32_setup(char * str)124 static int __init nonx32_setup(char *str)
125 {
126 if (!strcmp(str, "on"))
127 force_personality32 &= ~READ_IMPLIES_EXEC;
128 else if (!strcmp(str, "off"))
129 force_personality32 |= READ_IMPLIES_EXEC;
130 return 1;
131 }
132 __setup("noexec32=", nonx32_setup);
133
sync_global_pgds_l5(unsigned long start,unsigned long end)134 static void sync_global_pgds_l5(unsigned long start, unsigned long end)
135 {
136 unsigned long addr;
137
138 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
139 const pgd_t *pgd_ref = pgd_offset_k(addr);
140 struct page *page;
141
142 /* Check for overflow */
143 if (addr < start)
144 break;
145
146 if (pgd_none(*pgd_ref))
147 continue;
148
149 spin_lock(&pgd_lock);
150 list_for_each_entry(page, &pgd_list, lru) {
151 pgd_t *pgd;
152 spinlock_t *pgt_lock;
153
154 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
155 /* the pgt_lock only for Xen */
156 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
157 spin_lock(pgt_lock);
158
159 if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
160 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
161
162 if (pgd_none(*pgd))
163 set_pgd(pgd, *pgd_ref);
164
165 spin_unlock(pgt_lock);
166 }
167 spin_unlock(&pgd_lock);
168 }
169 }
170
sync_global_pgds_l4(unsigned long start,unsigned long end)171 static void sync_global_pgds_l4(unsigned long start, unsigned long end)
172 {
173 unsigned long addr;
174
175 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
176 pgd_t *pgd_ref = pgd_offset_k(addr);
177 const p4d_t *p4d_ref;
178 struct page *page;
179
180 /*
181 * With folded p4d, pgd_none() is always false, we need to
182 * handle synchronization on p4d level.
183 */
184 MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref));
185 p4d_ref = p4d_offset(pgd_ref, addr);
186
187 if (p4d_none(*p4d_ref))
188 continue;
189
190 spin_lock(&pgd_lock);
191 list_for_each_entry(page, &pgd_list, lru) {
192 pgd_t *pgd;
193 p4d_t *p4d;
194 spinlock_t *pgt_lock;
195
196 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
197 p4d = p4d_offset(pgd, addr);
198 /* the pgt_lock only for Xen */
199 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
200 spin_lock(pgt_lock);
201
202 if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
203 BUG_ON(p4d_pgtable(*p4d)
204 != p4d_pgtable(*p4d_ref));
205
206 if (p4d_none(*p4d))
207 set_p4d(p4d, *p4d_ref);
208
209 spin_unlock(pgt_lock);
210 }
211 spin_unlock(&pgd_lock);
212 }
213 }
214
215 /*
216 * When memory was added make sure all the processes MM have
217 * suitable PGD entries in the local PGD level page.
218 */
sync_global_pgds(unsigned long start,unsigned long end)219 static void sync_global_pgds(unsigned long start, unsigned long end)
220 {
221 if (pgtable_l5_enabled())
222 sync_global_pgds_l5(start, end);
223 else
224 sync_global_pgds_l4(start, end);
225 }
226
227 /*
228 * NOTE: This function is marked __ref because it calls __init function
229 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
230 */
spp_getpage(void)231 static __ref void *spp_getpage(void)
232 {
233 void *ptr;
234
235 if (after_bootmem)
236 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
237 else
238 ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
239
240 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
241 panic("set_pte_phys: cannot allocate page data %s\n",
242 after_bootmem ? "after bootmem" : "");
243 }
244
245 pr_debug("spp_getpage %p\n", ptr);
246
247 return ptr;
248 }
249
fill_p4d(pgd_t * pgd,unsigned long vaddr)250 static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
251 {
252 if (pgd_none(*pgd)) {
253 p4d_t *p4d = (p4d_t *)spp_getpage();
254 pgd_populate(&init_mm, pgd, p4d);
255 if (p4d != p4d_offset(pgd, 0))
256 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
257 p4d, p4d_offset(pgd, 0));
258 }
259 return p4d_offset(pgd, vaddr);
260 }
261
fill_pud(p4d_t * p4d,unsigned long vaddr)262 static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
263 {
264 if (p4d_none(*p4d)) {
265 pud_t *pud = (pud_t *)spp_getpage();
266 p4d_populate(&init_mm, p4d, pud);
267 if (pud != pud_offset(p4d, 0))
268 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
269 pud, pud_offset(p4d, 0));
270 }
271 return pud_offset(p4d, vaddr);
272 }
273
fill_pmd(pud_t * pud,unsigned long vaddr)274 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
275 {
276 if (pud_none(*pud)) {
277 pmd_t *pmd = (pmd_t *) spp_getpage();
278 pud_populate(&init_mm, pud, pmd);
279 if (pmd != pmd_offset(pud, 0))
280 printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
281 pmd, pmd_offset(pud, 0));
282 }
283 return pmd_offset(pud, vaddr);
284 }
285
fill_pte(pmd_t * pmd,unsigned long vaddr)286 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
287 {
288 if (pmd_none(*pmd)) {
289 pte_t *pte = (pte_t *) spp_getpage();
290 pmd_populate_kernel(&init_mm, pmd, pte);
291 if (pte != pte_offset_kernel(pmd, 0))
292 printk(KERN_ERR "PAGETABLE BUG #03!\n");
293 }
294 return pte_offset_kernel(pmd, vaddr);
295 }
296
__set_pte_vaddr(pud_t * pud,unsigned long vaddr,pte_t new_pte)297 static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
298 {
299 pmd_t *pmd = fill_pmd(pud, vaddr);
300 pte_t *pte = fill_pte(pmd, vaddr);
301
302 set_pte(pte, new_pte);
303
304 /*
305 * It's enough to flush this one mapping.
306 * (PGE mappings get flushed as well)
307 */
308 flush_tlb_one_kernel(vaddr);
309 }
310
set_pte_vaddr_p4d(p4d_t * p4d_page,unsigned long vaddr,pte_t new_pte)311 void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
312 {
313 p4d_t *p4d = p4d_page + p4d_index(vaddr);
314 pud_t *pud = fill_pud(p4d, vaddr);
315
316 __set_pte_vaddr(pud, vaddr, new_pte);
317 }
318
set_pte_vaddr_pud(pud_t * pud_page,unsigned long vaddr,pte_t new_pte)319 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
320 {
321 pud_t *pud = pud_page + pud_index(vaddr);
322
323 __set_pte_vaddr(pud, vaddr, new_pte);
324 }
325
set_pte_vaddr(unsigned long vaddr,pte_t pteval)326 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
327 {
328 pgd_t *pgd;
329 p4d_t *p4d_page;
330
331 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
332
333 pgd = pgd_offset_k(vaddr);
334 if (pgd_none(*pgd)) {
335 printk(KERN_ERR
336 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
337 return;
338 }
339
340 p4d_page = p4d_offset(pgd, 0);
341 set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
342 }
343
populate_extra_pmd(unsigned long vaddr)344 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
345 {
346 pgd_t *pgd;
347 p4d_t *p4d;
348 pud_t *pud;
349
350 pgd = pgd_offset_k(vaddr);
351 p4d = fill_p4d(pgd, vaddr);
352 pud = fill_pud(p4d, vaddr);
353 return fill_pmd(pud, vaddr);
354 }
355
populate_extra_pte(unsigned long vaddr)356 pte_t * __init populate_extra_pte(unsigned long vaddr)
357 {
358 pmd_t *pmd;
359
360 pmd = populate_extra_pmd(vaddr);
361 return fill_pte(pmd, vaddr);
362 }
363
364 /*
365 * Create large page table mappings for a range of physical addresses.
366 */
__init_extra_mapping(unsigned long phys,unsigned long size,enum page_cache_mode cache)367 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
368 enum page_cache_mode cache)
369 {
370 pgd_t *pgd;
371 p4d_t *p4d;
372 pud_t *pud;
373 pmd_t *pmd;
374 pgprot_t prot;
375
376 pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
377 protval_4k_2_large(cachemode2protval(cache));
378 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
379 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
380 pgd = pgd_offset_k((unsigned long)__va(phys));
381 if (pgd_none(*pgd)) {
382 p4d = (p4d_t *) spp_getpage();
383 set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
384 _PAGE_USER));
385 }
386 p4d = p4d_offset(pgd, (unsigned long)__va(phys));
387 if (p4d_none(*p4d)) {
388 pud = (pud_t *) spp_getpage();
389 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
390 _PAGE_USER));
391 }
392 pud = pud_offset(p4d, (unsigned long)__va(phys));
393 if (pud_none(*pud)) {
394 pmd = (pmd_t *) spp_getpage();
395 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
396 _PAGE_USER));
397 }
398 pmd = pmd_offset(pud, phys);
399 BUG_ON(!pmd_none(*pmd));
400 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
401 }
402 }
403
init_extra_mapping_wb(unsigned long phys,unsigned long size)404 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
405 {
406 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
407 }
408
init_extra_mapping_uc(unsigned long phys,unsigned long size)409 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
410 {
411 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
412 }
413
414 /*
415 * The head.S code sets up the kernel high mapping:
416 *
417 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
418 *
419 * phys_base holds the negative offset to the kernel, which is added
420 * to the compile time generated pmds. This results in invalid pmds up
421 * to the point where we hit the physaddr 0 mapping.
422 *
423 * We limit the mappings to the region from _text to _brk_end. _brk_end
424 * is rounded up to the 2MB boundary. This catches the invalid pmds as
425 * well, as they are located before _text:
426 */
cleanup_highmap(void)427 void __init cleanup_highmap(void)
428 {
429 unsigned long vaddr = __START_KERNEL_map;
430 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
431 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
432 pmd_t *pmd = level2_kernel_pgt;
433
434 /*
435 * Native path, max_pfn_mapped is not set yet.
436 * Xen has valid max_pfn_mapped set in
437 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
438 */
439 if (max_pfn_mapped)
440 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
441
442 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
443 if (pmd_none(*pmd))
444 continue;
445 if (vaddr < (unsigned long) _text || vaddr > end)
446 set_pmd(pmd, __pmd(0));
447 }
448 }
449
450 /*
451 * Create PTE level page table mapping for physical addresses.
452 * It returns the last physical address mapped.
453 */
454 static unsigned long __meminit
phys_pte_init(pte_t * pte_page,unsigned long paddr,unsigned long paddr_end,pgprot_t prot,bool init)455 phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
456 pgprot_t prot, bool init)
457 {
458 unsigned long pages = 0, paddr_next;
459 unsigned long paddr_last = paddr_end;
460 pte_t *pte;
461 int i;
462
463 pte = pte_page + pte_index(paddr);
464 i = pte_index(paddr);
465
466 for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
467 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
468 if (paddr >= paddr_end) {
469 if (!after_bootmem &&
470 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
471 E820_TYPE_RAM) &&
472 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
473 E820_TYPE_ACPI))
474 set_pte_init(pte, __pte(0), init);
475 continue;
476 }
477
478 /*
479 * We will re-use the existing mapping.
480 * Xen for example has some special requirements, like mapping
481 * pagetable pages as RO. So assume someone who pre-setup
482 * these mappings are more intelligent.
483 */
484 if (!pte_none(*pte)) {
485 if (!after_bootmem)
486 pages++;
487 continue;
488 }
489
490 if (0)
491 pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr,
492 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
493 pages++;
494 set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init);
495 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
496 }
497
498 update_page_count(PG_LEVEL_4K, pages);
499
500 return paddr_last;
501 }
502
503 /*
504 * Create PMD level page table mapping for physical addresses. The virtual
505 * and physical address have to be aligned at this level.
506 * It returns the last physical address mapped.
507 */
508 static unsigned long __meminit
phys_pmd_init(pmd_t * pmd_page,unsigned long paddr,unsigned long paddr_end,unsigned long page_size_mask,pgprot_t prot,bool init)509 phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
510 unsigned long page_size_mask, pgprot_t prot, bool init)
511 {
512 unsigned long pages = 0, paddr_next;
513 unsigned long paddr_last = paddr_end;
514
515 int i = pmd_index(paddr);
516
517 for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
518 pmd_t *pmd = pmd_page + pmd_index(paddr);
519 pte_t *pte;
520 pgprot_t new_prot = prot;
521
522 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
523 if (paddr >= paddr_end) {
524 if (!after_bootmem &&
525 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
526 E820_TYPE_RAM) &&
527 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
528 E820_TYPE_ACPI))
529 set_pmd_init(pmd, __pmd(0), init);
530 continue;
531 }
532
533 if (!pmd_none(*pmd)) {
534 if (!pmd_leaf(*pmd)) {
535 spin_lock(&init_mm.page_table_lock);
536 pte = (pte_t *)pmd_page_vaddr(*pmd);
537 paddr_last = phys_pte_init(pte, paddr,
538 paddr_end, prot,
539 init);
540 spin_unlock(&init_mm.page_table_lock);
541 continue;
542 }
543 /*
544 * If we are ok with PG_LEVEL_2M mapping, then we will
545 * use the existing mapping,
546 *
547 * Otherwise, we will split the large page mapping but
548 * use the same existing protection bits except for
549 * large page, so that we don't violate Intel's TLB
550 * Application note (317080) which says, while changing
551 * the page sizes, new and old translations should
552 * not differ with respect to page frame and
553 * attributes.
554 */
555 if (page_size_mask & (1 << PG_LEVEL_2M)) {
556 if (!after_bootmem)
557 pages++;
558 paddr_last = paddr_next;
559 continue;
560 }
561 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
562 }
563
564 if (page_size_mask & (1<<PG_LEVEL_2M)) {
565 pages++;
566 spin_lock(&init_mm.page_table_lock);
567 set_pmd_init(pmd,
568 pfn_pmd(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
569 init);
570 spin_unlock(&init_mm.page_table_lock);
571 paddr_last = paddr_next;
572 continue;
573 }
574
575 pte = alloc_low_page();
576 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init);
577
578 spin_lock(&init_mm.page_table_lock);
579 pmd_populate_kernel_init(&init_mm, pmd, pte, init);
580 spin_unlock(&init_mm.page_table_lock);
581 }
582 update_page_count(PG_LEVEL_2M, pages);
583 return paddr_last;
584 }
585
586 /*
587 * Create PUD level page table mapping for physical addresses. The virtual
588 * and physical address do not have to be aligned at this level. KASLR can
589 * randomize virtual addresses up to this level.
590 * It returns the last physical address mapped.
591 */
592 static unsigned long __meminit
phys_pud_init(pud_t * pud_page,unsigned long paddr,unsigned long paddr_end,unsigned long page_size_mask,pgprot_t _prot,bool init)593 phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
594 unsigned long page_size_mask, pgprot_t _prot, bool init)
595 {
596 unsigned long pages = 0, paddr_next;
597 unsigned long paddr_last = paddr_end;
598 unsigned long vaddr = (unsigned long)__va(paddr);
599 int i = pud_index(vaddr);
600
601 for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
602 pud_t *pud;
603 pmd_t *pmd;
604 pgprot_t prot = _prot;
605
606 vaddr = (unsigned long)__va(paddr);
607 pud = pud_page + pud_index(vaddr);
608 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
609
610 if (paddr >= paddr_end) {
611 if (!after_bootmem &&
612 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
613 E820_TYPE_RAM) &&
614 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
615 E820_TYPE_ACPI))
616 set_pud_init(pud, __pud(0), init);
617 continue;
618 }
619
620 if (!pud_none(*pud)) {
621 if (!pud_leaf(*pud)) {
622 pmd = pmd_offset(pud, 0);
623 paddr_last = phys_pmd_init(pmd, paddr,
624 paddr_end,
625 page_size_mask,
626 prot, init);
627 continue;
628 }
629 /*
630 * If we are ok with PG_LEVEL_1G mapping, then we will
631 * use the existing mapping.
632 *
633 * Otherwise, we will split the gbpage mapping but use
634 * the same existing protection bits except for large
635 * page, so that we don't violate Intel's TLB
636 * Application note (317080) which says, while changing
637 * the page sizes, new and old translations should
638 * not differ with respect to page frame and
639 * attributes.
640 */
641 if (page_size_mask & (1 << PG_LEVEL_1G)) {
642 if (!after_bootmem)
643 pages++;
644 paddr_last = paddr_next;
645 continue;
646 }
647 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
648 }
649
650 if (page_size_mask & (1<<PG_LEVEL_1G)) {
651 pages++;
652 spin_lock(&init_mm.page_table_lock);
653 set_pud_init(pud,
654 pfn_pud(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
655 init);
656 spin_unlock(&init_mm.page_table_lock);
657 paddr_last = paddr_next;
658 continue;
659 }
660
661 pmd = alloc_low_page();
662 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
663 page_size_mask, prot, init);
664
665 spin_lock(&init_mm.page_table_lock);
666 pud_populate_init(&init_mm, pud, pmd, init);
667 spin_unlock(&init_mm.page_table_lock);
668 }
669
670 update_page_count(PG_LEVEL_1G, pages);
671
672 return paddr_last;
673 }
674
675 static unsigned long __meminit
phys_p4d_init(p4d_t * p4d_page,unsigned long paddr,unsigned long paddr_end,unsigned long page_size_mask,pgprot_t prot,bool init)676 phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
677 unsigned long page_size_mask, pgprot_t prot, bool init)
678 {
679 unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last;
680
681 paddr_last = paddr_end;
682 vaddr = (unsigned long)__va(paddr);
683 vaddr_end = (unsigned long)__va(paddr_end);
684
685 if (!pgtable_l5_enabled())
686 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end,
687 page_size_mask, prot, init);
688
689 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
690 p4d_t *p4d = p4d_page + p4d_index(vaddr);
691 pud_t *pud;
692
693 vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE;
694 paddr = __pa(vaddr);
695
696 if (paddr >= paddr_end) {
697 paddr_next = __pa(vaddr_next);
698 if (!after_bootmem &&
699 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
700 E820_TYPE_RAM) &&
701 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
702 E820_TYPE_ACPI))
703 set_p4d_init(p4d, __p4d(0), init);
704 continue;
705 }
706
707 if (!p4d_none(*p4d)) {
708 pud = pud_offset(p4d, 0);
709 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
710 page_size_mask, prot, init);
711 continue;
712 }
713
714 pud = alloc_low_page();
715 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
716 page_size_mask, prot, init);
717
718 spin_lock(&init_mm.page_table_lock);
719 p4d_populate_init(&init_mm, p4d, pud, init);
720 spin_unlock(&init_mm.page_table_lock);
721 }
722
723 return paddr_last;
724 }
725
726 static unsigned long __meminit
__kernel_physical_mapping_init(unsigned long paddr_start,unsigned long paddr_end,unsigned long page_size_mask,pgprot_t prot,bool init)727 __kernel_physical_mapping_init(unsigned long paddr_start,
728 unsigned long paddr_end,
729 unsigned long page_size_mask,
730 pgprot_t prot, bool init)
731 {
732 bool pgd_changed = false;
733 unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
734
735 paddr_last = paddr_end;
736 vaddr = (unsigned long)__va(paddr_start);
737 vaddr_end = (unsigned long)__va(paddr_end);
738 vaddr_start = vaddr;
739
740 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
741 pgd_t *pgd = pgd_offset_k(vaddr);
742 p4d_t *p4d;
743
744 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
745
746 if (pgd_val(*pgd)) {
747 p4d = (p4d_t *)pgd_page_vaddr(*pgd);
748 paddr_last = phys_p4d_init(p4d, __pa(vaddr),
749 __pa(vaddr_end),
750 page_size_mask,
751 prot, init);
752 continue;
753 }
754
755 p4d = alloc_low_page();
756 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
757 page_size_mask, prot, init);
758
759 spin_lock(&init_mm.page_table_lock);
760 if (pgtable_l5_enabled())
761 pgd_populate_init(&init_mm, pgd, p4d, init);
762 else
763 p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr),
764 (pud_t *) p4d, init);
765
766 spin_unlock(&init_mm.page_table_lock);
767 pgd_changed = true;
768 }
769
770 if (pgd_changed)
771 sync_global_pgds(vaddr_start, vaddr_end - 1);
772
773 return paddr_last;
774 }
775
776
777 /*
778 * Create page table mapping for the physical memory for specific physical
779 * addresses. Note that it can only be used to populate non-present entries.
780 * The virtual and physical addresses have to be aligned on PMD level
781 * down. It returns the last physical address mapped.
782 */
783 unsigned long __meminit
kernel_physical_mapping_init(unsigned long paddr_start,unsigned long paddr_end,unsigned long page_size_mask,pgprot_t prot)784 kernel_physical_mapping_init(unsigned long paddr_start,
785 unsigned long paddr_end,
786 unsigned long page_size_mask, pgprot_t prot)
787 {
788 return __kernel_physical_mapping_init(paddr_start, paddr_end,
789 page_size_mask, prot, true);
790 }
791
792 /*
793 * This function is similar to kernel_physical_mapping_init() above with the
794 * exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe()
795 * when updating the mapping. The caller is responsible to flush the TLBs after
796 * the function returns.
797 */
798 unsigned long __meminit
kernel_physical_mapping_change(unsigned long paddr_start,unsigned long paddr_end,unsigned long page_size_mask)799 kernel_physical_mapping_change(unsigned long paddr_start,
800 unsigned long paddr_end,
801 unsigned long page_size_mask)
802 {
803 return __kernel_physical_mapping_init(paddr_start, paddr_end,
804 page_size_mask, PAGE_KERNEL,
805 false);
806 }
807
808 #ifndef CONFIG_NUMA
initmem_init(void)809 void __init initmem_init(void)
810 {
811 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
812 }
813 #endif
814
paging_init(void)815 void __init paging_init(void)
816 {
817 sparse_init();
818
819 /*
820 * clear the default setting with node 0
821 * note: don't use nodes_clear here, that is really clearing when
822 * numa support is not compiled in, and later node_set_state
823 * will not set it back.
824 */
825 node_clear_state(0, N_MEMORY);
826 node_clear_state(0, N_NORMAL_MEMORY);
827
828 zone_sizes_init();
829 }
830
831 #ifdef CONFIG_SPARSEMEM_VMEMMAP
832 #define PAGE_UNUSED 0xFD
833
834 /*
835 * The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges
836 * from unused_pmd_start to next PMD_SIZE boundary.
837 */
838 static unsigned long unused_pmd_start __meminitdata;
839
vmemmap_flush_unused_pmd(void)840 static void __meminit vmemmap_flush_unused_pmd(void)
841 {
842 if (!unused_pmd_start)
843 return;
844 /*
845 * Clears (unused_pmd_start, PMD_END]
846 */
847 memset((void *)unused_pmd_start, PAGE_UNUSED,
848 ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start);
849 unused_pmd_start = 0;
850 }
851
852 #ifdef CONFIG_MEMORY_HOTPLUG
853 /* Returns true if the PMD is completely unused and thus it can be freed */
vmemmap_pmd_is_unused(unsigned long addr,unsigned long end)854 static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end)
855 {
856 unsigned long start = ALIGN_DOWN(addr, PMD_SIZE);
857
858 /*
859 * Flush the unused range cache to ensure that memchr_inv() will work
860 * for the whole range.
861 */
862 vmemmap_flush_unused_pmd();
863 memset((void *)addr, PAGE_UNUSED, end - addr);
864
865 return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE);
866 }
867 #endif
868
__vmemmap_use_sub_pmd(unsigned long start)869 static void __meminit __vmemmap_use_sub_pmd(unsigned long start)
870 {
871 /*
872 * As we expect to add in the same granularity as we remove, it's
873 * sufficient to mark only some piece used to block the memmap page from
874 * getting removed when removing some other adjacent memmap (just in
875 * case the first memmap never gets initialized e.g., because the memory
876 * block never gets onlined).
877 */
878 memset((void *)start, 0, sizeof(struct page));
879 }
880
vmemmap_use_sub_pmd(unsigned long start,unsigned long end)881 static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end)
882 {
883 /*
884 * We only optimize if the new used range directly follows the
885 * previously unused range (esp., when populating consecutive sections).
886 */
887 if (unused_pmd_start == start) {
888 if (likely(IS_ALIGNED(end, PMD_SIZE)))
889 unused_pmd_start = 0;
890 else
891 unused_pmd_start = end;
892 return;
893 }
894
895 /*
896 * If the range does not contiguously follows previous one, make sure
897 * to mark the unused range of the previous one so it can be removed.
898 */
899 vmemmap_flush_unused_pmd();
900 __vmemmap_use_sub_pmd(start);
901 }
902
903
vmemmap_use_new_sub_pmd(unsigned long start,unsigned long end)904 static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
905 {
906 const unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
907
908 vmemmap_flush_unused_pmd();
909
910 /*
911 * Could be our memmap page is filled with PAGE_UNUSED already from a
912 * previous remove. Make sure to reset it.
913 */
914 __vmemmap_use_sub_pmd(start);
915
916 /*
917 * Mark with PAGE_UNUSED the unused parts of the new memmap range
918 */
919 if (!IS_ALIGNED(start, PMD_SIZE))
920 memset((void *)page, PAGE_UNUSED, start - page);
921
922 /*
923 * We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of
924 * consecutive sections. Remember for the last added PMD where the
925 * unused range begins.
926 */
927 if (!IS_ALIGNED(end, PMD_SIZE))
928 unused_pmd_start = end;
929 }
930 #endif
931
932 /*
933 * Memory hotplug specific functions
934 */
935 #ifdef CONFIG_MEMORY_HOTPLUG
936 /*
937 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
938 * updating.
939 */
update_end_of_memory_vars(u64 start,u64 size)940 static void update_end_of_memory_vars(u64 start, u64 size)
941 {
942 unsigned long end_pfn = PFN_UP(start + size);
943
944 if (end_pfn > max_pfn) {
945 max_pfn = end_pfn;
946 max_low_pfn = end_pfn;
947 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
948 }
949 }
950
add_pages(int nid,unsigned long start_pfn,unsigned long nr_pages,struct mhp_params * params)951 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
952 struct mhp_params *params)
953 {
954 unsigned long end = ((start_pfn + nr_pages) << PAGE_SHIFT) - 1;
955 int ret;
956
957 if (WARN_ON_ONCE(end > DIRECT_MAP_PHYSMEM_END))
958 return -ERANGE;
959
960 ret = __add_pages(nid, start_pfn, nr_pages, params);
961 WARN_ON_ONCE(ret);
962
963 /*
964 * Special case: add_pages() is called by memremap_pages() for adding device
965 * private pages. Do not bump up max_pfn in the device private path,
966 * because max_pfn changes affect dma_addressing_limited().
967 *
968 * dma_addressing_limited() returning true when max_pfn is the device's
969 * addressable memory can force device drivers to use bounce buffers
970 * and impact their performance negatively:
971 */
972 if (!params->pgmap)
973 /* update max_pfn, max_low_pfn and high_memory */
974 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, nr_pages << PAGE_SHIFT);
975
976 return ret;
977 }
978
arch_add_memory(int nid,u64 start,u64 size,struct mhp_params * params)979 int arch_add_memory(int nid, u64 start, u64 size,
980 struct mhp_params *params)
981 {
982 unsigned long start_pfn = start >> PAGE_SHIFT;
983 unsigned long nr_pages = size >> PAGE_SHIFT;
984
985 init_memory_mapping(start, start + size, params->pgprot);
986
987 return add_pages(nid, start_pfn, nr_pages, params);
988 }
989
free_reserved_pages(struct page * page,unsigned long nr_pages)990 static void free_reserved_pages(struct page *page, unsigned long nr_pages)
991 {
992 while (nr_pages--)
993 free_reserved_page(page++);
994 }
995
free_pagetable(struct page * page,int order)996 static void __meminit free_pagetable(struct page *page, int order)
997 {
998 /* bootmem page has reserved flag */
999 if (PageReserved(page)) {
1000 unsigned long nr_pages = 1 << order;
1001 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
1002 enum bootmem_type type = bootmem_type(page);
1003
1004 if (type == SECTION_INFO || type == MIX_SECTION_INFO) {
1005 while (nr_pages--)
1006 put_page_bootmem(page++);
1007 } else {
1008 free_reserved_pages(page, nr_pages);
1009 }
1010 #else
1011 free_reserved_pages(page, nr_pages);
1012 #endif
1013 } else {
1014 free_pages((unsigned long)page_address(page), order);
1015 }
1016 }
1017
free_hugepage_table(struct page * page,struct vmem_altmap * altmap)1018 static void __meminit free_hugepage_table(struct page *page,
1019 struct vmem_altmap *altmap)
1020 {
1021 if (altmap)
1022 vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE);
1023 else
1024 free_pagetable(page, get_order(PMD_SIZE));
1025 }
1026
free_pte_table(pte_t * pte_start,pmd_t * pmd)1027 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
1028 {
1029 pte_t *pte;
1030 int i;
1031
1032 for (i = 0; i < PTRS_PER_PTE; i++) {
1033 pte = pte_start + i;
1034 if (!pte_none(*pte))
1035 return;
1036 }
1037
1038 /* free a pte table */
1039 free_pagetable(pmd_page(*pmd), 0);
1040 spin_lock(&init_mm.page_table_lock);
1041 pmd_clear(pmd);
1042 spin_unlock(&init_mm.page_table_lock);
1043 }
1044
free_pmd_table(pmd_t * pmd_start,pud_t * pud)1045 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
1046 {
1047 pmd_t *pmd;
1048 int i;
1049
1050 for (i = 0; i < PTRS_PER_PMD; i++) {
1051 pmd = pmd_start + i;
1052 if (!pmd_none(*pmd))
1053 return;
1054 }
1055
1056 /* free a pmd table */
1057 free_pagetable(pud_page(*pud), 0);
1058 spin_lock(&init_mm.page_table_lock);
1059 pud_clear(pud);
1060 spin_unlock(&init_mm.page_table_lock);
1061 }
1062
free_pud_table(pud_t * pud_start,p4d_t * p4d)1063 static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
1064 {
1065 pud_t *pud;
1066 int i;
1067
1068 for (i = 0; i < PTRS_PER_PUD; i++) {
1069 pud = pud_start + i;
1070 if (!pud_none(*pud))
1071 return;
1072 }
1073
1074 /* free a pud table */
1075 free_pagetable(p4d_page(*p4d), 0);
1076 spin_lock(&init_mm.page_table_lock);
1077 p4d_clear(p4d);
1078 spin_unlock(&init_mm.page_table_lock);
1079 }
1080
1081 static void __meminit
remove_pte_table(pte_t * pte_start,unsigned long addr,unsigned long end,bool direct)1082 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
1083 bool direct)
1084 {
1085 unsigned long next, pages = 0;
1086 pte_t *pte;
1087 phys_addr_t phys_addr;
1088
1089 pte = pte_start + pte_index(addr);
1090 for (; addr < end; addr = next, pte++) {
1091 next = (addr + PAGE_SIZE) & PAGE_MASK;
1092 if (next > end)
1093 next = end;
1094
1095 if (!pte_present(*pte))
1096 continue;
1097
1098 /*
1099 * We mapped [0,1G) memory as identity mapping when
1100 * initializing, in arch/x86/kernel/head_64.S. These
1101 * pagetables cannot be removed.
1102 */
1103 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
1104 if (phys_addr < (phys_addr_t)0x40000000)
1105 return;
1106
1107 if (!direct)
1108 free_pagetable(pte_page(*pte), 0);
1109
1110 spin_lock(&init_mm.page_table_lock);
1111 pte_clear(&init_mm, addr, pte);
1112 spin_unlock(&init_mm.page_table_lock);
1113
1114 /* For non-direct mapping, pages means nothing. */
1115 pages++;
1116 }
1117
1118 /* Call free_pte_table() in remove_pmd_table(). */
1119 flush_tlb_all();
1120 if (direct)
1121 update_page_count(PG_LEVEL_4K, -pages);
1122 }
1123
1124 static void __meminit
remove_pmd_table(pmd_t * pmd_start,unsigned long addr,unsigned long end,bool direct,struct vmem_altmap * altmap)1125 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
1126 bool direct, struct vmem_altmap *altmap)
1127 {
1128 unsigned long next, pages = 0;
1129 pte_t *pte_base;
1130 pmd_t *pmd;
1131
1132 pmd = pmd_start + pmd_index(addr);
1133 for (; addr < end; addr = next, pmd++) {
1134 next = pmd_addr_end(addr, end);
1135
1136 if (!pmd_present(*pmd))
1137 continue;
1138
1139 if (pmd_leaf(*pmd)) {
1140 if (IS_ALIGNED(addr, PMD_SIZE) &&
1141 IS_ALIGNED(next, PMD_SIZE)) {
1142 if (!direct)
1143 free_hugepage_table(pmd_page(*pmd),
1144 altmap);
1145
1146 spin_lock(&init_mm.page_table_lock);
1147 pmd_clear(pmd);
1148 spin_unlock(&init_mm.page_table_lock);
1149 pages++;
1150 }
1151 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1152 else if (vmemmap_pmd_is_unused(addr, next)) {
1153 free_hugepage_table(pmd_page(*pmd),
1154 altmap);
1155 spin_lock(&init_mm.page_table_lock);
1156 pmd_clear(pmd);
1157 spin_unlock(&init_mm.page_table_lock);
1158 }
1159 #endif
1160 continue;
1161 }
1162
1163 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
1164 remove_pte_table(pte_base, addr, next, direct);
1165 free_pte_table(pte_base, pmd);
1166 }
1167
1168 /* Call free_pmd_table() in remove_pud_table(). */
1169 if (direct)
1170 update_page_count(PG_LEVEL_2M, -pages);
1171 }
1172
1173 static void __meminit
remove_pud_table(pud_t * pud_start,unsigned long addr,unsigned long end,struct vmem_altmap * altmap,bool direct)1174 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
1175 struct vmem_altmap *altmap, bool direct)
1176 {
1177 unsigned long next, pages = 0;
1178 pmd_t *pmd_base;
1179 pud_t *pud;
1180
1181 pud = pud_start + pud_index(addr);
1182 for (; addr < end; addr = next, pud++) {
1183 next = pud_addr_end(addr, end);
1184
1185 if (!pud_present(*pud))
1186 continue;
1187
1188 if (pud_leaf(*pud) &&
1189 IS_ALIGNED(addr, PUD_SIZE) &&
1190 IS_ALIGNED(next, PUD_SIZE)) {
1191 spin_lock(&init_mm.page_table_lock);
1192 pud_clear(pud);
1193 spin_unlock(&init_mm.page_table_lock);
1194 pages++;
1195 continue;
1196 }
1197
1198 pmd_base = pmd_offset(pud, 0);
1199 remove_pmd_table(pmd_base, addr, next, direct, altmap);
1200 free_pmd_table(pmd_base, pud);
1201 }
1202
1203 if (direct)
1204 update_page_count(PG_LEVEL_1G, -pages);
1205 }
1206
1207 static void __meminit
remove_p4d_table(p4d_t * p4d_start,unsigned long addr,unsigned long end,struct vmem_altmap * altmap,bool direct)1208 remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
1209 struct vmem_altmap *altmap, bool direct)
1210 {
1211 unsigned long next, pages = 0;
1212 pud_t *pud_base;
1213 p4d_t *p4d;
1214
1215 p4d = p4d_start + p4d_index(addr);
1216 for (; addr < end; addr = next, p4d++) {
1217 next = p4d_addr_end(addr, end);
1218
1219 if (!p4d_present(*p4d))
1220 continue;
1221
1222 BUILD_BUG_ON(p4d_leaf(*p4d));
1223
1224 pud_base = pud_offset(p4d, 0);
1225 remove_pud_table(pud_base, addr, next, altmap, direct);
1226 /*
1227 * For 4-level page tables we do not want to free PUDs, but in the
1228 * 5-level case we should free them. This code will have to change
1229 * to adapt for boot-time switching between 4 and 5 level page tables.
1230 */
1231 if (pgtable_l5_enabled())
1232 free_pud_table(pud_base, p4d);
1233 }
1234
1235 if (direct)
1236 update_page_count(PG_LEVEL_512G, -pages);
1237 }
1238
1239 /* start and end are both virtual address. */
1240 static void __meminit
remove_pagetable(unsigned long start,unsigned long end,bool direct,struct vmem_altmap * altmap)1241 remove_pagetable(unsigned long start, unsigned long end, bool direct,
1242 struct vmem_altmap *altmap)
1243 {
1244 unsigned long next;
1245 unsigned long addr;
1246 pgd_t *pgd;
1247 p4d_t *p4d;
1248
1249 for (addr = start; addr < end; addr = next) {
1250 next = pgd_addr_end(addr, end);
1251
1252 pgd = pgd_offset_k(addr);
1253 if (!pgd_present(*pgd))
1254 continue;
1255
1256 p4d = p4d_offset(pgd, 0);
1257 remove_p4d_table(p4d, addr, next, altmap, direct);
1258 }
1259
1260 flush_tlb_all();
1261 }
1262
vmemmap_free(unsigned long start,unsigned long end,struct vmem_altmap * altmap)1263 void __ref vmemmap_free(unsigned long start, unsigned long end,
1264 struct vmem_altmap *altmap)
1265 {
1266 VM_BUG_ON(!PAGE_ALIGNED(start));
1267 VM_BUG_ON(!PAGE_ALIGNED(end));
1268
1269 remove_pagetable(start, end, false, altmap);
1270 }
1271
1272 static void __meminit
kernel_physical_mapping_remove(unsigned long start,unsigned long end)1273 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1274 {
1275 start = (unsigned long)__va(start);
1276 end = (unsigned long)__va(end);
1277
1278 remove_pagetable(start, end, true, NULL);
1279 }
1280
arch_remove_memory(u64 start,u64 size,struct vmem_altmap * altmap)1281 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
1282 {
1283 unsigned long start_pfn = start >> PAGE_SHIFT;
1284 unsigned long nr_pages = size >> PAGE_SHIFT;
1285
1286 __remove_pages(start_pfn, nr_pages, altmap);
1287 kernel_physical_mapping_remove(start, start + size);
1288 }
1289 #endif /* CONFIG_MEMORY_HOTPLUG */
1290
1291 static struct kcore_list kcore_vsyscall;
1292
register_page_bootmem_info(void)1293 static void __init register_page_bootmem_info(void)
1294 {
1295 #if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP)
1296 int i;
1297
1298 for_each_online_node(i)
1299 register_page_bootmem_info_node(NODE_DATA(i));
1300 #endif
1301 }
1302
1303 /*
1304 * Pre-allocates page-table pages for the vmalloc area in the kernel page-table.
1305 * Only the level which needs to be synchronized between all page-tables is
1306 * allocated because the synchronization can be expensive.
1307 */
preallocate_vmalloc_pages(void)1308 static void __init preallocate_vmalloc_pages(void)
1309 {
1310 unsigned long addr;
1311 const char *lvl;
1312
1313 for (addr = VMALLOC_START; addr <= VMEMORY_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1314 pgd_t *pgd = pgd_offset_k(addr);
1315 p4d_t *p4d;
1316 pud_t *pud;
1317
1318 lvl = "p4d";
1319 p4d = p4d_alloc(&init_mm, pgd, addr);
1320 if (!p4d)
1321 goto failed;
1322
1323 if (pgtable_l5_enabled())
1324 continue;
1325
1326 /*
1327 * The goal here is to allocate all possibly required
1328 * hardware page tables pointed to by the top hardware
1329 * level.
1330 *
1331 * On 4-level systems, the P4D layer is folded away and
1332 * the above code does no preallocation. Below, go down
1333 * to the pud _software_ level to ensure the second
1334 * hardware level is allocated on 4-level systems too.
1335 */
1336 lvl = "pud";
1337 pud = pud_alloc(&init_mm, p4d, addr);
1338 if (!pud)
1339 goto failed;
1340 }
1341
1342 return;
1343
1344 failed:
1345
1346 /*
1347 * The pages have to be there now or they will be missing in
1348 * process page-tables later.
1349 */
1350 panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl);
1351 }
1352
arch_mm_preinit(void)1353 void __init arch_mm_preinit(void)
1354 {
1355 pci_iommu_alloc();
1356 }
1357
mem_init(void)1358 void __init mem_init(void)
1359 {
1360 /* clear_bss() already clear the empty_zero_page */
1361
1362 after_bootmem = 1;
1363 x86_init.hyper.init_after_bootmem();
1364
1365 /*
1366 * Must be done after boot memory is put on freelist, because here we
1367 * might set fields in deferred struct pages that have not yet been
1368 * initialized, and memblock_free_all() initializes all the reserved
1369 * deferred pages for us.
1370 */
1371 register_page_bootmem_info();
1372
1373 /* Register memory areas for /proc/kcore */
1374 if (get_gate_vma(&init_mm))
1375 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
1376
1377 preallocate_vmalloc_pages();
1378 }
1379
1380 int kernel_set_to_readonly;
1381
mark_rodata_ro(void)1382 void mark_rodata_ro(void)
1383 {
1384 unsigned long start = PFN_ALIGN(_text);
1385 unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1386 unsigned long end = (unsigned long)__end_rodata_hpage_align;
1387 unsigned long text_end = PFN_ALIGN(_etext);
1388 unsigned long rodata_end = PFN_ALIGN(__end_rodata);
1389 unsigned long all_end;
1390
1391 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1392 (end - start) >> 10);
1393 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1394
1395 execmem_cache_make_ro();
1396
1397 kernel_set_to_readonly = 1;
1398
1399 /*
1400 * The rodata/data/bss/brk section (but not the kernel text!)
1401 * should also be not-executable.
1402 *
1403 * We align all_end to PMD_SIZE because the existing mapping
1404 * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1405 * split the PMD and the reminder between _brk_end and the end
1406 * of the PMD will remain mapped executable.
1407 *
1408 * Any PMD which was setup after the one which covers _brk_end
1409 * has been zapped already via cleanup_highmem().
1410 */
1411 all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1412 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1413
1414 set_ftrace_ops_ro();
1415
1416 #ifdef CONFIG_CPA_DEBUG
1417 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1418 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1419
1420 printk(KERN_INFO "Testing CPA: again\n");
1421 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1422 #endif
1423
1424 free_kernel_image_pages("unused kernel image (text/rodata gap)",
1425 (void *)text_end, (void *)rodata_start);
1426 free_kernel_image_pages("unused kernel image (rodata/data gap)",
1427 (void *)rodata_end, (void *)_sdata);
1428 }
1429
1430 /*
1431 * Block size is the minimum amount of memory which can be hotplugged or
1432 * hotremoved. It must be power of two and must be equal or larger than
1433 * MIN_MEMORY_BLOCK_SIZE.
1434 */
1435 #define MAX_BLOCK_SIZE (2UL << 30)
1436
1437 /* Amount of ram needed to start using large blocks */
1438 #define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30)
1439
1440 /* Adjustable memory block size */
1441 static unsigned long set_memory_block_size;
set_memory_block_size_order(unsigned int order)1442 int __init set_memory_block_size_order(unsigned int order)
1443 {
1444 unsigned long size = 1UL << order;
1445
1446 if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE)
1447 return -EINVAL;
1448
1449 set_memory_block_size = size;
1450 return 0;
1451 }
1452
probe_memory_block_size(void)1453 static unsigned long probe_memory_block_size(void)
1454 {
1455 unsigned long boot_mem_end = max_pfn << PAGE_SHIFT;
1456 unsigned long bz;
1457
1458 /* If memory block size has been set, then use it */
1459 bz = set_memory_block_size;
1460 if (bz)
1461 goto done;
1462
1463 /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */
1464 if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) {
1465 bz = MIN_MEMORY_BLOCK_SIZE;
1466 goto done;
1467 }
1468
1469 /*
1470 * Use max block size to minimize overhead on bare metal, where
1471 * alignment for memory hotplug isn't a concern.
1472 */
1473 if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
1474 bz = MAX_BLOCK_SIZE;
1475 goto done;
1476 }
1477
1478 /* Find the largest allowed block size that aligns to memory end */
1479 for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) {
1480 if (IS_ALIGNED(boot_mem_end, bz))
1481 break;
1482 }
1483 done:
1484 pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1485
1486 return bz;
1487 }
1488
1489 static unsigned long memory_block_size_probed;
memory_block_size_bytes(void)1490 unsigned long memory_block_size_bytes(void)
1491 {
1492 if (!memory_block_size_probed)
1493 memory_block_size_probed = probe_memory_block_size();
1494
1495 return memory_block_size_probed;
1496 }
1497
1498 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1499 /*
1500 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1501 */
1502 static long __meminitdata addr_start, addr_end;
1503 static void __meminitdata *p_start, *p_end;
1504 static int __meminitdata node_start;
1505
vmemmap_set_pmd(pmd_t * pmd,void * p,int node,unsigned long addr,unsigned long next)1506 void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
1507 unsigned long addr, unsigned long next)
1508 {
1509 pte_t entry;
1510
1511 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1512 PAGE_KERNEL_LARGE);
1513 set_pmd(pmd, __pmd(pte_val(entry)));
1514
1515 /* check to see if we have contiguous blocks */
1516 if (p_end != p || node_start != node) {
1517 if (p_start)
1518 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1519 addr_start, addr_end-1, p_start, p_end-1, node_start);
1520 addr_start = addr;
1521 node_start = node;
1522 p_start = p;
1523 }
1524
1525 addr_end = addr + PMD_SIZE;
1526 p_end = p + PMD_SIZE;
1527
1528 if (!IS_ALIGNED(addr, PMD_SIZE) ||
1529 !IS_ALIGNED(next, PMD_SIZE))
1530 vmemmap_use_new_sub_pmd(addr, next);
1531 }
1532
vmemmap_check_pmd(pmd_t * pmd,int node,unsigned long addr,unsigned long next)1533 int __meminit vmemmap_check_pmd(pmd_t *pmd, int node,
1534 unsigned long addr, unsigned long next)
1535 {
1536 int large = pmd_leaf(*pmd);
1537
1538 if (pmd_leaf(*pmd)) {
1539 vmemmap_verify((pte_t *)pmd, node, addr, next);
1540 vmemmap_use_sub_pmd(addr, next);
1541 }
1542
1543 return large;
1544 }
1545
vmemmap_populate(unsigned long start,unsigned long end,int node,struct vmem_altmap * altmap)1546 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1547 struct vmem_altmap *altmap)
1548 {
1549 int err;
1550
1551 VM_BUG_ON(!PAGE_ALIGNED(start));
1552 VM_BUG_ON(!PAGE_ALIGNED(end));
1553
1554 if (end - start < PAGES_PER_SECTION * sizeof(struct page))
1555 err = vmemmap_populate_basepages(start, end, node, NULL);
1556 else if (boot_cpu_has(X86_FEATURE_PSE))
1557 err = vmemmap_populate_hugepages(start, end, node, altmap);
1558 else if (altmap) {
1559 pr_err_once("%s: no cpu support for altmap allocations\n",
1560 __func__);
1561 err = -ENOMEM;
1562 } else
1563 err = vmemmap_populate_basepages(start, end, node, NULL);
1564 if (!err)
1565 sync_global_pgds(start, end - 1);
1566 return err;
1567 }
1568
1569 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
register_page_bootmem_memmap(unsigned long section_nr,struct page * start_page,unsigned long nr_pages)1570 void register_page_bootmem_memmap(unsigned long section_nr,
1571 struct page *start_page, unsigned long nr_pages)
1572 {
1573 unsigned long addr = (unsigned long)start_page;
1574 unsigned long end = (unsigned long)(start_page + nr_pages);
1575 unsigned long next;
1576 pgd_t *pgd;
1577 p4d_t *p4d;
1578 pud_t *pud;
1579 pmd_t *pmd;
1580 unsigned int nr_pmd_pages;
1581 struct page *page;
1582
1583 for (; addr < end; addr = next) {
1584 pte_t *pte = NULL;
1585
1586 pgd = pgd_offset_k(addr);
1587 if (pgd_none(*pgd)) {
1588 next = (addr + PAGE_SIZE) & PAGE_MASK;
1589 continue;
1590 }
1591 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1592
1593 p4d = p4d_offset(pgd, addr);
1594 if (p4d_none(*p4d)) {
1595 next = (addr + PAGE_SIZE) & PAGE_MASK;
1596 continue;
1597 }
1598 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
1599
1600 pud = pud_offset(p4d, addr);
1601 if (pud_none(*pud)) {
1602 next = (addr + PAGE_SIZE) & PAGE_MASK;
1603 continue;
1604 }
1605 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1606
1607 pmd = pmd_offset(pud, addr);
1608 if (pmd_none(*pmd)) {
1609 next = (addr + PAGE_SIZE) & PAGE_MASK;
1610 continue;
1611 }
1612
1613 if (!boot_cpu_has(X86_FEATURE_PSE) || !pmd_leaf(*pmd)) {
1614 next = (addr + PAGE_SIZE) & PAGE_MASK;
1615 get_page_bootmem(section_nr, pmd_page(*pmd),
1616 MIX_SECTION_INFO);
1617
1618 pte = pte_offset_kernel(pmd, addr);
1619 if (pte_none(*pte))
1620 continue;
1621 get_page_bootmem(section_nr, pte_page(*pte),
1622 SECTION_INFO);
1623 } else {
1624 next = pmd_addr_end(addr, end);
1625 nr_pmd_pages = (next - addr) >> PAGE_SHIFT;
1626 page = pmd_page(*pmd);
1627 while (nr_pmd_pages--)
1628 get_page_bootmem(section_nr, page++,
1629 SECTION_INFO);
1630 }
1631 }
1632 }
1633 #endif
1634
vmemmap_populate_print_last(void)1635 void __meminit vmemmap_populate_print_last(void)
1636 {
1637 if (p_start) {
1638 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1639 addr_start, addr_end-1, p_start, p_end-1, node_start);
1640 p_start = NULL;
1641 p_end = NULL;
1642 node_start = 0;
1643 }
1644 }
1645 #endif
1646