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
94 /*
95 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
96 * physical space so we can cache the place of the first one and move
97 * around without checking the pgd every time.
98 */
99
100 /* Bits supported by the hardware: */
101 pteval_t __supported_pte_mask __read_mostly = ~0;
102 /* Bits allowed in normal kernel mappings: */
103 pteval_t __default_kernel_pte_mask __read_mostly = ~0;
104 EXPORT_SYMBOL_GPL(__supported_pte_mask);
105 /* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
106 EXPORT_SYMBOL(__default_kernel_pte_mask);
107
108 int force_personality32;
109
110 /*
111 * noexec32=on|off
112 * Control non executable heap for 32bit processes.
113 * To control the stack too use noexec=off
114 *
115 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
116 * off PROT_READ implies PROT_EXEC
117 */
nonx32_setup(char * str)118 static int __init nonx32_setup(char *str)
119 {
120 if (!strcmp(str, "on"))
121 force_personality32 &= ~READ_IMPLIES_EXEC;
122 else if (!strcmp(str, "off"))
123 force_personality32 |= READ_IMPLIES_EXEC;
124 return 1;
125 }
126 __setup("noexec32=", nonx32_setup);
127
sync_global_pgds_l5(unsigned long start,unsigned long end)128 static void sync_global_pgds_l5(unsigned long start, unsigned long end)
129 {
130 unsigned long addr;
131
132 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
133 const pgd_t *pgd_ref = pgd_offset_k(addr);
134 struct page *page;
135
136 /* Check for overflow */
137 if (addr < start)
138 break;
139
140 if (pgd_none(*pgd_ref))
141 continue;
142
143 spin_lock(&pgd_lock);
144 list_for_each_entry(page, &pgd_list, lru) {
145 pgd_t *pgd;
146 spinlock_t *pgt_lock;
147
148 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
149 /* the pgt_lock only for Xen */
150 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
151 spin_lock(pgt_lock);
152
153 if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
154 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
155
156 if (pgd_none(*pgd))
157 set_pgd(pgd, *pgd_ref);
158
159 spin_unlock(pgt_lock);
160 }
161 spin_unlock(&pgd_lock);
162 }
163 }
164
sync_global_pgds_l4(unsigned long start,unsigned long end)165 static void sync_global_pgds_l4(unsigned long start, unsigned long end)
166 {
167 unsigned long addr;
168
169 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
170 pgd_t *pgd_ref = pgd_offset_k(addr);
171 const p4d_t *p4d_ref;
172 struct page *page;
173
174 /*
175 * With folded p4d, pgd_none() is always false, we need to
176 * handle synchronization on p4d level.
177 */
178 MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref));
179 p4d_ref = p4d_offset(pgd_ref, addr);
180
181 if (p4d_none(*p4d_ref))
182 continue;
183
184 spin_lock(&pgd_lock);
185 list_for_each_entry(page, &pgd_list, lru) {
186 pgd_t *pgd;
187 p4d_t *p4d;
188 spinlock_t *pgt_lock;
189
190 pgd = (pgd_t *)page_address(page) + pgd_index(addr);
191 p4d = p4d_offset(pgd, addr);
192 /* the pgt_lock only for Xen */
193 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
194 spin_lock(pgt_lock);
195
196 if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
197 BUG_ON(p4d_pgtable(*p4d)
198 != p4d_pgtable(*p4d_ref));
199
200 if (p4d_none(*p4d))
201 set_p4d(p4d, *p4d_ref);
202
203 spin_unlock(pgt_lock);
204 }
205 spin_unlock(&pgd_lock);
206 }
207 }
208
209 /*
210 * When memory was added make sure all the processes MM have
211 * suitable PGD entries in the local PGD level page.
212 */
sync_global_pgds(unsigned long start,unsigned long end)213 static void sync_global_pgds(unsigned long start, unsigned long end)
214 {
215 if (pgtable_l5_enabled())
216 sync_global_pgds_l5(start, end);
217 else
218 sync_global_pgds_l4(start, end);
219 }
220
221 /*
222 * NOTE: This function is marked __ref because it calls __init function
223 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
224 */
spp_getpage(void)225 static __ref void *spp_getpage(void)
226 {
227 void *ptr;
228
229 if (after_bootmem)
230 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
231 else
232 ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
233
234 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
235 panic("set_pte_phys: cannot allocate page data %s\n",
236 after_bootmem ? "after bootmem" : "");
237 }
238
239 pr_debug("spp_getpage %p\n", ptr);
240
241 return ptr;
242 }
243
fill_p4d(pgd_t * pgd,unsigned long vaddr)244 static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
245 {
246 if (pgd_none(*pgd)) {
247 p4d_t *p4d = (p4d_t *)spp_getpage();
248 pgd_populate(&init_mm, pgd, p4d);
249 if (p4d != p4d_offset(pgd, 0))
250 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
251 p4d, p4d_offset(pgd, 0));
252 }
253 return p4d_offset(pgd, vaddr);
254 }
255
fill_pud(p4d_t * p4d,unsigned long vaddr)256 static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
257 {
258 if (p4d_none(*p4d)) {
259 pud_t *pud = (pud_t *)spp_getpage();
260 p4d_populate(&init_mm, p4d, pud);
261 if (pud != pud_offset(p4d, 0))
262 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
263 pud, pud_offset(p4d, 0));
264 }
265 return pud_offset(p4d, vaddr);
266 }
267
fill_pmd(pud_t * pud,unsigned long vaddr)268 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
269 {
270 if (pud_none(*pud)) {
271 pmd_t *pmd = (pmd_t *) spp_getpage();
272 pud_populate(&init_mm, pud, pmd);
273 if (pmd != pmd_offset(pud, 0))
274 printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
275 pmd, pmd_offset(pud, 0));
276 }
277 return pmd_offset(pud, vaddr);
278 }
279
fill_pte(pmd_t * pmd,unsigned long vaddr)280 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
281 {
282 if (pmd_none(*pmd)) {
283 pte_t *pte = (pte_t *) spp_getpage();
284 pmd_populate_kernel(&init_mm, pmd, pte);
285 if (pte != pte_offset_kernel(pmd, 0))
286 printk(KERN_ERR "PAGETABLE BUG #03!\n");
287 }
288 return pte_offset_kernel(pmd, vaddr);
289 }
290
__set_pte_vaddr(pud_t * pud,unsigned long vaddr,pte_t new_pte)291 static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
292 {
293 pmd_t *pmd = fill_pmd(pud, vaddr);
294 pte_t *pte = fill_pte(pmd, vaddr);
295
296 set_pte(pte, new_pte);
297
298 /*
299 * It's enough to flush this one mapping.
300 * (PGE mappings get flushed as well)
301 */
302 flush_tlb_one_kernel(vaddr);
303 }
304
set_pte_vaddr_p4d(p4d_t * p4d_page,unsigned long vaddr,pte_t new_pte)305 void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
306 {
307 p4d_t *p4d = p4d_page + p4d_index(vaddr);
308 pud_t *pud = fill_pud(p4d, vaddr);
309
310 __set_pte_vaddr(pud, vaddr, new_pte);
311 }
312
set_pte_vaddr_pud(pud_t * pud_page,unsigned long vaddr,pte_t new_pte)313 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
314 {
315 pud_t *pud = pud_page + pud_index(vaddr);
316
317 __set_pte_vaddr(pud, vaddr, new_pte);
318 }
319
set_pte_vaddr(unsigned long vaddr,pte_t pteval)320 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
321 {
322 pgd_t *pgd;
323 p4d_t *p4d_page;
324
325 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
326
327 pgd = pgd_offset_k(vaddr);
328 if (pgd_none(*pgd)) {
329 printk(KERN_ERR
330 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
331 return;
332 }
333
334 p4d_page = p4d_offset(pgd, 0);
335 set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
336 }
337
populate_extra_pmd(unsigned long vaddr)338 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
339 {
340 pgd_t *pgd;
341 p4d_t *p4d;
342 pud_t *pud;
343
344 pgd = pgd_offset_k(vaddr);
345 p4d = fill_p4d(pgd, vaddr);
346 pud = fill_pud(p4d, vaddr);
347 return fill_pmd(pud, vaddr);
348 }
349
populate_extra_pte(unsigned long vaddr)350 pte_t * __init populate_extra_pte(unsigned long vaddr)
351 {
352 pmd_t *pmd;
353
354 pmd = populate_extra_pmd(vaddr);
355 return fill_pte(pmd, vaddr);
356 }
357
358 /*
359 * Create large page table mappings for a range of physical addresses.
360 */
__init_extra_mapping(unsigned long phys,unsigned long size,enum page_cache_mode cache)361 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
362 enum page_cache_mode cache)
363 {
364 pgd_t *pgd;
365 p4d_t *p4d;
366 pud_t *pud;
367 pmd_t *pmd;
368 pgprot_t prot;
369
370 pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
371 protval_4k_2_large(cachemode2protval(cache));
372 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
373 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
374 pgd = pgd_offset_k((unsigned long)__va(phys));
375 if (pgd_none(*pgd)) {
376 p4d = (p4d_t *) spp_getpage();
377 set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
378 _PAGE_USER));
379 }
380 p4d = p4d_offset(pgd, (unsigned long)__va(phys));
381 if (p4d_none(*p4d)) {
382 pud = (pud_t *) spp_getpage();
383 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
384 _PAGE_USER));
385 }
386 pud = pud_offset(p4d, (unsigned long)__va(phys));
387 if (pud_none(*pud)) {
388 pmd = (pmd_t *) spp_getpage();
389 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
390 _PAGE_USER));
391 }
392 pmd = pmd_offset(pud, phys);
393 BUG_ON(!pmd_none(*pmd));
394 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
395 }
396 }
397
init_extra_mapping_wb(unsigned long phys,unsigned long size)398 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
399 {
400 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
401 }
402
init_extra_mapping_uc(unsigned long phys,unsigned long size)403 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
404 {
405 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
406 }
407
408 /*
409 * The head.S code sets up the kernel high mapping:
410 *
411 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
412 *
413 * phys_base holds the negative offset to the kernel, which is added
414 * to the compile time generated pmds. This results in invalid pmds up
415 * to the point where we hit the physaddr 0 mapping.
416 *
417 * We limit the mappings to the region from _text to _brk_end. _brk_end
418 * is rounded up to the 2MB boundary. This catches the invalid pmds as
419 * well, as they are located before _text:
420 */
cleanup_highmap(void)421 void __init cleanup_highmap(void)
422 {
423 unsigned long vaddr = __START_KERNEL_map;
424 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
425 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
426 pmd_t *pmd = level2_kernel_pgt;
427
428 /*
429 * Native path, max_pfn_mapped is not set yet.
430 * Xen has valid max_pfn_mapped set in
431 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
432 */
433 if (max_pfn_mapped)
434 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
435
436 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
437 if (pmd_none(*pmd))
438 continue;
439 if (vaddr < (unsigned long) _text || vaddr > end)
440 set_pmd(pmd, __pmd(0));
441 }
442 }
443
444 /*
445 * Create PTE level page table mapping for physical addresses.
446 * It returns the last physical address mapped.
447 */
448 static unsigned long __meminit
phys_pte_init(pte_t * pte_page,unsigned long paddr,unsigned long paddr_end,pgprot_t prot,bool init)449 phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
450 pgprot_t prot, bool init)
451 {
452 unsigned long pages = 0, paddr_next;
453 unsigned long paddr_last = paddr_end;
454 pte_t *pte;
455 int i;
456
457 pte = pte_page + pte_index(paddr);
458 i = pte_index(paddr);
459
460 for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
461 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
462 if (paddr >= paddr_end) {
463 if (!after_bootmem &&
464 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
465 E820_TYPE_RAM) &&
466 !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
467 E820_TYPE_RESERVED_KERN))
468 set_pte_init(pte, __pte(0), init);
469 continue;
470 }
471
472 /*
473 * We will re-use the existing mapping.
474 * Xen for example has some special requirements, like mapping
475 * pagetable pages as RO. So assume someone who pre-setup
476 * these mappings are more intelligent.
477 */
478 if (!pte_none(*pte)) {
479 if (!after_bootmem)
480 pages++;
481 continue;
482 }
483
484 if (0)
485 pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr,
486 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
487 pages++;
488 set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init);
489 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
490 }
491
492 update_page_count(PG_LEVEL_4K, pages);
493
494 return paddr_last;
495 }
496
497 /*
498 * Create PMD level page table mapping for physical addresses. The virtual
499 * and physical address have to be aligned at this level.
500 * It returns the last physical address mapped.
501 */
502 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)503 phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
504 unsigned long page_size_mask, pgprot_t prot, bool init)
505 {
506 unsigned long pages = 0, paddr_next;
507 unsigned long paddr_last = paddr_end;
508
509 int i = pmd_index(paddr);
510
511 for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
512 pmd_t *pmd = pmd_page + pmd_index(paddr);
513 pte_t *pte;
514 pgprot_t new_prot = prot;
515
516 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
517 if (paddr >= paddr_end) {
518 if (!after_bootmem &&
519 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
520 E820_TYPE_RAM) &&
521 !e820__mapped_any(paddr & PMD_MASK, paddr_next,
522 E820_TYPE_RESERVED_KERN))
523 set_pmd_init(pmd, __pmd(0), init);
524 continue;
525 }
526
527 if (!pmd_none(*pmd)) {
528 if (!pmd_large(*pmd)) {
529 spin_lock(&init_mm.page_table_lock);
530 pte = (pte_t *)pmd_page_vaddr(*pmd);
531 paddr_last = phys_pte_init(pte, paddr,
532 paddr_end, prot,
533 init);
534 spin_unlock(&init_mm.page_table_lock);
535 continue;
536 }
537 /*
538 * If we are ok with PG_LEVEL_2M mapping, then we will
539 * use the existing mapping,
540 *
541 * Otherwise, we will split the large page mapping but
542 * use the same existing protection bits except for
543 * large page, so that we don't violate Intel's TLB
544 * Application note (317080) which says, while changing
545 * the page sizes, new and old translations should
546 * not differ with respect to page frame and
547 * attributes.
548 */
549 if (page_size_mask & (1 << PG_LEVEL_2M)) {
550 if (!after_bootmem)
551 pages++;
552 paddr_last = paddr_next;
553 continue;
554 }
555 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
556 }
557
558 if (page_size_mask & (1<<PG_LEVEL_2M)) {
559 pages++;
560 spin_lock(&init_mm.page_table_lock);
561 set_pte_init((pte_t *)pmd,
562 pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT,
563 __pgprot(pgprot_val(prot) | _PAGE_PSE)),
564 init);
565 spin_unlock(&init_mm.page_table_lock);
566 paddr_last = paddr_next;
567 continue;
568 }
569
570 pte = alloc_low_page();
571 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init);
572
573 spin_lock(&init_mm.page_table_lock);
574 pmd_populate_kernel_init(&init_mm, pmd, pte, init);
575 spin_unlock(&init_mm.page_table_lock);
576 }
577 update_page_count(PG_LEVEL_2M, pages);
578 return paddr_last;
579 }
580
581 /*
582 * Create PUD level page table mapping for physical addresses. The virtual
583 * and physical address do not have to be aligned at this level. KASLR can
584 * randomize virtual addresses up to this level.
585 * It returns the last physical address mapped.
586 */
587 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)588 phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
589 unsigned long page_size_mask, pgprot_t _prot, bool init)
590 {
591 unsigned long pages = 0, paddr_next;
592 unsigned long paddr_last = paddr_end;
593 unsigned long vaddr = (unsigned long)__va(paddr);
594 int i = pud_index(vaddr);
595
596 for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
597 pud_t *pud;
598 pmd_t *pmd;
599 pgprot_t prot = _prot;
600
601 vaddr = (unsigned long)__va(paddr);
602 pud = pud_page + pud_index(vaddr);
603 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
604
605 if (paddr >= paddr_end) {
606 if (!after_bootmem &&
607 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
608 E820_TYPE_RAM) &&
609 !e820__mapped_any(paddr & PUD_MASK, paddr_next,
610 E820_TYPE_RESERVED_KERN))
611 set_pud_init(pud, __pud(0), init);
612 continue;
613 }
614
615 if (!pud_none(*pud)) {
616 if (!pud_large(*pud)) {
617 pmd = pmd_offset(pud, 0);
618 paddr_last = phys_pmd_init(pmd, paddr,
619 paddr_end,
620 page_size_mask,
621 prot, init);
622 continue;
623 }
624 /*
625 * If we are ok with PG_LEVEL_1G mapping, then we will
626 * use the existing mapping.
627 *
628 * Otherwise, we will split the gbpage mapping but use
629 * the same existing protection bits except for large
630 * page, so that we don't violate Intel's TLB
631 * Application note (317080) which says, while changing
632 * the page sizes, new and old translations should
633 * not differ with respect to page frame and
634 * attributes.
635 */
636 if (page_size_mask & (1 << PG_LEVEL_1G)) {
637 if (!after_bootmem)
638 pages++;
639 paddr_last = paddr_next;
640 continue;
641 }
642 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
643 }
644
645 if (page_size_mask & (1<<PG_LEVEL_1G)) {
646 pages++;
647 spin_lock(&init_mm.page_table_lock);
648
649 prot = __pgprot(pgprot_val(prot) | _PAGE_PSE);
650
651 set_pte_init((pte_t *)pud,
652 pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,
653 prot),
654 init);
655 spin_unlock(&init_mm.page_table_lock);
656 paddr_last = paddr_next;
657 continue;
658 }
659
660 pmd = alloc_low_page();
661 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
662 page_size_mask, prot, init);
663
664 spin_lock(&init_mm.page_table_lock);
665 pud_populate_init(&init_mm, pud, pmd, init);
666 spin_unlock(&init_mm.page_table_lock);
667 }
668
669 update_page_count(PG_LEVEL_1G, pages);
670
671 return paddr_last;
672 }
673
674 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)675 phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
676 unsigned long page_size_mask, pgprot_t prot, bool init)
677 {
678 unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last;
679
680 paddr_last = paddr_end;
681 vaddr = (unsigned long)__va(paddr);
682 vaddr_end = (unsigned long)__va(paddr_end);
683
684 if (!pgtable_l5_enabled())
685 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end,
686 page_size_mask, prot, init);
687
688 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
689 p4d_t *p4d = p4d_page + p4d_index(vaddr);
690 pud_t *pud;
691
692 vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE;
693 paddr = __pa(vaddr);
694
695 if (paddr >= paddr_end) {
696 paddr_next = __pa(vaddr_next);
697 if (!after_bootmem &&
698 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
699 E820_TYPE_RAM) &&
700 !e820__mapped_any(paddr & P4D_MASK, paddr_next,
701 E820_TYPE_RESERVED_KERN))
702 set_p4d_init(p4d, __p4d(0), init);
703 continue;
704 }
705
706 if (!p4d_none(*p4d)) {
707 pud = pud_offset(p4d, 0);
708 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
709 page_size_mask, prot, init);
710 continue;
711 }
712
713 pud = alloc_low_page();
714 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
715 page_size_mask, prot, init);
716
717 spin_lock(&init_mm.page_table_lock);
718 p4d_populate_init(&init_mm, p4d, pud, init);
719 spin_unlock(&init_mm.page_table_lock);
720 }
721
722 return paddr_last;
723 }
724
725 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)726 __kernel_physical_mapping_init(unsigned long paddr_start,
727 unsigned long paddr_end,
728 unsigned long page_size_mask,
729 pgprot_t prot, bool init)
730 {
731 bool pgd_changed = false;
732 unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
733
734 paddr_last = paddr_end;
735 vaddr = (unsigned long)__va(paddr_start);
736 vaddr_end = (unsigned long)__va(paddr_end);
737 vaddr_start = vaddr;
738
739 for (; vaddr < vaddr_end; vaddr = vaddr_next) {
740 pgd_t *pgd = pgd_offset_k(vaddr);
741 p4d_t *p4d;
742
743 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
744
745 if (pgd_val(*pgd)) {
746 p4d = (p4d_t *)pgd_page_vaddr(*pgd);
747 paddr_last = phys_p4d_init(p4d, __pa(vaddr),
748 __pa(vaddr_end),
749 page_size_mask,
750 prot, init);
751 continue;
752 }
753
754 p4d = alloc_low_page();
755 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
756 page_size_mask, prot, init);
757
758 spin_lock(&init_mm.page_table_lock);
759 if (pgtable_l5_enabled())
760 pgd_populate_init(&init_mm, pgd, p4d, init);
761 else
762 p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr),
763 (pud_t *) p4d, init);
764
765 spin_unlock(&init_mm.page_table_lock);
766 pgd_changed = true;
767 }
768
769 if (pgd_changed)
770 sync_global_pgds(vaddr_start, vaddr_end - 1);
771
772 return paddr_last;
773 }
774
775
776 /*
777 * Create page table mapping for the physical memory for specific physical
778 * addresses. Note that it can only be used to populate non-present entries.
779 * The virtual and physical addresses have to be aligned on PMD level
780 * down. It returns the last physical address mapped.
781 */
782 unsigned long __meminit
kernel_physical_mapping_init(unsigned long paddr_start,unsigned long paddr_end,unsigned long page_size_mask,pgprot_t prot)783 kernel_physical_mapping_init(unsigned long paddr_start,
784 unsigned long paddr_end,
785 unsigned long page_size_mask, pgprot_t prot)
786 {
787 return __kernel_physical_mapping_init(paddr_start, paddr_end,
788 page_size_mask, prot, true);
789 }
790
791 /*
792 * This function is similar to kernel_physical_mapping_init() above with the
793 * exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe()
794 * when updating the mapping. The caller is responsible to flush the TLBs after
795 * the function returns.
796 */
797 unsigned long __meminit
kernel_physical_mapping_change(unsigned long paddr_start,unsigned long paddr_end,unsigned long page_size_mask)798 kernel_physical_mapping_change(unsigned long paddr_start,
799 unsigned long paddr_end,
800 unsigned long page_size_mask)
801 {
802 return __kernel_physical_mapping_init(paddr_start, paddr_end,
803 page_size_mask, PAGE_KERNEL,
804 false);
805 }
806
807 #ifndef CONFIG_NUMA
initmem_init(void)808 void __init initmem_init(void)
809 {
810 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
811 }
812 #endif
813
paging_init(void)814 void __init paging_init(void)
815 {
816 sparse_init();
817
818 /*
819 * clear the default setting with node 0
820 * note: don't use nodes_clear here, that is really clearing when
821 * numa support is not compiled in, and later node_set_state
822 * will not set it back.
823 */
824 node_clear_state(0, N_MEMORY);
825 node_clear_state(0, N_NORMAL_MEMORY);
826
827 zone_sizes_init();
828 }
829
830 #ifdef CONFIG_SPARSEMEM_VMEMMAP
831 #define PAGE_UNUSED 0xFD
832
833 /*
834 * The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges
835 * from unused_pmd_start to next PMD_SIZE boundary.
836 */
837 static unsigned long unused_pmd_start __meminitdata;
838
vmemmap_flush_unused_pmd(void)839 static void __meminit vmemmap_flush_unused_pmd(void)
840 {
841 if (!unused_pmd_start)
842 return;
843 /*
844 * Clears (unused_pmd_start, PMD_END]
845 */
846 memset((void *)unused_pmd_start, PAGE_UNUSED,
847 ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start);
848 unused_pmd_start = 0;
849 }
850
851 #ifdef CONFIG_MEMORY_HOTPLUG
852 /* Returns true if the PMD is completely unused and thus it can be freed */
vmemmap_pmd_is_unused(unsigned long addr,unsigned long end)853 static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end)
854 {
855 unsigned long start = ALIGN_DOWN(addr, PMD_SIZE);
856
857 /*
858 * Flush the unused range cache to ensure that memchr_inv() will work
859 * for the whole range.
860 */
861 vmemmap_flush_unused_pmd();
862 memset((void *)addr, PAGE_UNUSED, end - addr);
863
864 return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE);
865 }
866 #endif
867
__vmemmap_use_sub_pmd(unsigned long start)868 static void __meminit __vmemmap_use_sub_pmd(unsigned long start)
869 {
870 /*
871 * As we expect to add in the same granularity as we remove, it's
872 * sufficient to mark only some piece used to block the memmap page from
873 * getting removed when removing some other adjacent memmap (just in
874 * case the first memmap never gets initialized e.g., because the memory
875 * block never gets onlined).
876 */
877 memset((void *)start, 0, sizeof(struct page));
878 }
879
vmemmap_use_sub_pmd(unsigned long start,unsigned long end)880 static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end)
881 {
882 /*
883 * We only optimize if the new used range directly follows the
884 * previously unused range (esp., when populating consecutive sections).
885 */
886 if (unused_pmd_start == start) {
887 if (likely(IS_ALIGNED(end, PMD_SIZE)))
888 unused_pmd_start = 0;
889 else
890 unused_pmd_start = end;
891 return;
892 }
893
894 /*
895 * If the range does not contiguously follows previous one, make sure
896 * to mark the unused range of the previous one so it can be removed.
897 */
898 vmemmap_flush_unused_pmd();
899 __vmemmap_use_sub_pmd(start);
900 }
901
902
vmemmap_use_new_sub_pmd(unsigned long start,unsigned long end)903 static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
904 {
905 const unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
906
907 vmemmap_flush_unused_pmd();
908
909 /*
910 * Could be our memmap page is filled with PAGE_UNUSED already from a
911 * previous remove. Make sure to reset it.
912 */
913 __vmemmap_use_sub_pmd(start);
914
915 /*
916 * Mark with PAGE_UNUSED the unused parts of the new memmap range
917 */
918 if (!IS_ALIGNED(start, PMD_SIZE))
919 memset((void *)page, PAGE_UNUSED, start - page);
920
921 /*
922 * We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of
923 * consecutive sections. Remember for the last added PMD where the
924 * unused range begins.
925 */
926 if (!IS_ALIGNED(end, PMD_SIZE))
927 unused_pmd_start = end;
928 }
929 #endif
930
931 /*
932 * Memory hotplug specific functions
933 */
934 #ifdef CONFIG_MEMORY_HOTPLUG
935 /*
936 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
937 * updating.
938 */
update_end_of_memory_vars(u64 start,u64 size)939 static void update_end_of_memory_vars(u64 start, u64 size)
940 {
941 unsigned long end_pfn = PFN_UP(start + size);
942
943 if (end_pfn > max_pfn) {
944 max_pfn = end_pfn;
945 max_low_pfn = end_pfn;
946 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
947 }
948 }
949
add_pages(int nid,unsigned long start_pfn,unsigned long nr_pages,struct mhp_params * params)950 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
951 struct mhp_params *params)
952 {
953 int ret;
954
955 ret = __add_pages(nid, start_pfn, nr_pages, params);
956 WARN_ON_ONCE(ret);
957
958 /* update max_pfn, max_low_pfn and high_memory */
959 update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
960 nr_pages << PAGE_SHIFT);
961
962 return ret;
963 }
964
arch_add_memory(int nid,u64 start,u64 size,struct mhp_params * params)965 int arch_add_memory(int nid, u64 start, u64 size,
966 struct mhp_params *params)
967 {
968 unsigned long start_pfn = start >> PAGE_SHIFT;
969 unsigned long nr_pages = size >> PAGE_SHIFT;
970
971 init_memory_mapping(start, start + size, params->pgprot);
972
973 return add_pages(nid, start_pfn, nr_pages, params);
974 }
975
free_pagetable(struct page * page,int order)976 static void __meminit free_pagetable(struct page *page, int order)
977 {
978 unsigned long magic;
979 unsigned int nr_pages = 1 << order;
980
981 /* bootmem page has reserved flag */
982 if (PageReserved(page)) {
983 __ClearPageReserved(page);
984
985 magic = (unsigned long)page->freelist;
986 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
987 while (nr_pages--)
988 put_page_bootmem(page++);
989 } else
990 while (nr_pages--)
991 free_reserved_page(page++);
992 } else
993 free_pages((unsigned long)page_address(page), order);
994 }
995
free_hugepage_table(struct page * page,struct vmem_altmap * altmap)996 static void __meminit free_hugepage_table(struct page *page,
997 struct vmem_altmap *altmap)
998 {
999 if (altmap)
1000 vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE);
1001 else
1002 free_pagetable(page, get_order(PMD_SIZE));
1003 }
1004
free_pte_table(pte_t * pte_start,pmd_t * pmd)1005 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
1006 {
1007 pte_t *pte;
1008 int i;
1009
1010 for (i = 0; i < PTRS_PER_PTE; i++) {
1011 pte = pte_start + i;
1012 if (!pte_none(*pte))
1013 return;
1014 }
1015
1016 /* free a pte talbe */
1017 free_pagetable(pmd_page(*pmd), 0);
1018 spin_lock(&init_mm.page_table_lock);
1019 pmd_clear(pmd);
1020 spin_unlock(&init_mm.page_table_lock);
1021 }
1022
free_pmd_table(pmd_t * pmd_start,pud_t * pud)1023 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
1024 {
1025 pmd_t *pmd;
1026 int i;
1027
1028 for (i = 0; i < PTRS_PER_PMD; i++) {
1029 pmd = pmd_start + i;
1030 if (!pmd_none(*pmd))
1031 return;
1032 }
1033
1034 /* free a pmd talbe */
1035 free_pagetable(pud_page(*pud), 0);
1036 spin_lock(&init_mm.page_table_lock);
1037 pud_clear(pud);
1038 spin_unlock(&init_mm.page_table_lock);
1039 }
1040
free_pud_table(pud_t * pud_start,p4d_t * p4d)1041 static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
1042 {
1043 pud_t *pud;
1044 int i;
1045
1046 for (i = 0; i < PTRS_PER_PUD; i++) {
1047 pud = pud_start + i;
1048 if (!pud_none(*pud))
1049 return;
1050 }
1051
1052 /* free a pud talbe */
1053 free_pagetable(p4d_page(*p4d), 0);
1054 spin_lock(&init_mm.page_table_lock);
1055 p4d_clear(p4d);
1056 spin_unlock(&init_mm.page_table_lock);
1057 }
1058
1059 static void __meminit
remove_pte_table(pte_t * pte_start,unsigned long addr,unsigned long end,bool direct)1060 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
1061 bool direct)
1062 {
1063 unsigned long next, pages = 0;
1064 pte_t *pte;
1065 phys_addr_t phys_addr;
1066
1067 pte = pte_start + pte_index(addr);
1068 for (; addr < end; addr = next, pte++) {
1069 next = (addr + PAGE_SIZE) & PAGE_MASK;
1070 if (next > end)
1071 next = end;
1072
1073 if (!pte_present(*pte))
1074 continue;
1075
1076 /*
1077 * We mapped [0,1G) memory as identity mapping when
1078 * initializing, in arch/x86/kernel/head_64.S. These
1079 * pagetables cannot be removed.
1080 */
1081 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
1082 if (phys_addr < (phys_addr_t)0x40000000)
1083 return;
1084
1085 if (!direct)
1086 free_pagetable(pte_page(*pte), 0);
1087
1088 spin_lock(&init_mm.page_table_lock);
1089 pte_clear(&init_mm, addr, pte);
1090 spin_unlock(&init_mm.page_table_lock);
1091
1092 /* For non-direct mapping, pages means nothing. */
1093 pages++;
1094 }
1095
1096 /* Call free_pte_table() in remove_pmd_table(). */
1097 flush_tlb_all();
1098 if (direct)
1099 update_page_count(PG_LEVEL_4K, -pages);
1100 }
1101
1102 static void __meminit
remove_pmd_table(pmd_t * pmd_start,unsigned long addr,unsigned long end,bool direct,struct vmem_altmap * altmap)1103 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
1104 bool direct, struct vmem_altmap *altmap)
1105 {
1106 unsigned long next, pages = 0;
1107 pte_t *pte_base;
1108 pmd_t *pmd;
1109
1110 pmd = pmd_start + pmd_index(addr);
1111 for (; addr < end; addr = next, pmd++) {
1112 next = pmd_addr_end(addr, end);
1113
1114 if (!pmd_present(*pmd))
1115 continue;
1116
1117 if (pmd_large(*pmd)) {
1118 if (IS_ALIGNED(addr, PMD_SIZE) &&
1119 IS_ALIGNED(next, PMD_SIZE)) {
1120 if (!direct)
1121 free_hugepage_table(pmd_page(*pmd),
1122 altmap);
1123
1124 spin_lock(&init_mm.page_table_lock);
1125 pmd_clear(pmd);
1126 spin_unlock(&init_mm.page_table_lock);
1127 pages++;
1128 }
1129 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1130 else if (vmemmap_pmd_is_unused(addr, next)) {
1131 free_hugepage_table(pmd_page(*pmd),
1132 altmap);
1133 spin_lock(&init_mm.page_table_lock);
1134 pmd_clear(pmd);
1135 spin_unlock(&init_mm.page_table_lock);
1136 }
1137 #endif
1138 continue;
1139 }
1140
1141 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
1142 remove_pte_table(pte_base, addr, next, direct);
1143 free_pte_table(pte_base, pmd);
1144 }
1145
1146 /* Call free_pmd_table() in remove_pud_table(). */
1147 if (direct)
1148 update_page_count(PG_LEVEL_2M, -pages);
1149 }
1150
1151 static void __meminit
remove_pud_table(pud_t * pud_start,unsigned long addr,unsigned long end,struct vmem_altmap * altmap,bool direct)1152 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
1153 struct vmem_altmap *altmap, bool direct)
1154 {
1155 unsigned long next, pages = 0;
1156 pmd_t *pmd_base;
1157 pud_t *pud;
1158
1159 pud = pud_start + pud_index(addr);
1160 for (; addr < end; addr = next, pud++) {
1161 next = pud_addr_end(addr, end);
1162
1163 if (!pud_present(*pud))
1164 continue;
1165
1166 if (pud_large(*pud) &&
1167 IS_ALIGNED(addr, PUD_SIZE) &&
1168 IS_ALIGNED(next, PUD_SIZE)) {
1169 spin_lock(&init_mm.page_table_lock);
1170 pud_clear(pud);
1171 spin_unlock(&init_mm.page_table_lock);
1172 pages++;
1173 continue;
1174 }
1175
1176 pmd_base = pmd_offset(pud, 0);
1177 remove_pmd_table(pmd_base, addr, next, direct, altmap);
1178 free_pmd_table(pmd_base, pud);
1179 }
1180
1181 if (direct)
1182 update_page_count(PG_LEVEL_1G, -pages);
1183 }
1184
1185 static void __meminit
remove_p4d_table(p4d_t * p4d_start,unsigned long addr,unsigned long end,struct vmem_altmap * altmap,bool direct)1186 remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
1187 struct vmem_altmap *altmap, bool direct)
1188 {
1189 unsigned long next, pages = 0;
1190 pud_t *pud_base;
1191 p4d_t *p4d;
1192
1193 p4d = p4d_start + p4d_index(addr);
1194 for (; addr < end; addr = next, p4d++) {
1195 next = p4d_addr_end(addr, end);
1196
1197 if (!p4d_present(*p4d))
1198 continue;
1199
1200 BUILD_BUG_ON(p4d_large(*p4d));
1201
1202 pud_base = pud_offset(p4d, 0);
1203 remove_pud_table(pud_base, addr, next, altmap, direct);
1204 /*
1205 * For 4-level page tables we do not want to free PUDs, but in the
1206 * 5-level case we should free them. This code will have to change
1207 * to adapt for boot-time switching between 4 and 5 level page tables.
1208 */
1209 if (pgtable_l5_enabled())
1210 free_pud_table(pud_base, p4d);
1211 }
1212
1213 if (direct)
1214 update_page_count(PG_LEVEL_512G, -pages);
1215 }
1216
1217 /* start and end are both virtual address. */
1218 static void __meminit
remove_pagetable(unsigned long start,unsigned long end,bool direct,struct vmem_altmap * altmap)1219 remove_pagetable(unsigned long start, unsigned long end, bool direct,
1220 struct vmem_altmap *altmap)
1221 {
1222 unsigned long next;
1223 unsigned long addr;
1224 pgd_t *pgd;
1225 p4d_t *p4d;
1226
1227 for (addr = start; addr < end; addr = next) {
1228 next = pgd_addr_end(addr, end);
1229
1230 pgd = pgd_offset_k(addr);
1231 if (!pgd_present(*pgd))
1232 continue;
1233
1234 p4d = p4d_offset(pgd, 0);
1235 remove_p4d_table(p4d, addr, next, altmap, direct);
1236 }
1237
1238 flush_tlb_all();
1239 }
1240
vmemmap_free(unsigned long start,unsigned long end,struct vmem_altmap * altmap)1241 void __ref vmemmap_free(unsigned long start, unsigned long end,
1242 struct vmem_altmap *altmap)
1243 {
1244 VM_BUG_ON(!IS_ALIGNED(start, PAGE_SIZE));
1245 VM_BUG_ON(!IS_ALIGNED(end, PAGE_SIZE));
1246
1247 remove_pagetable(start, end, false, altmap);
1248 }
1249
1250 static void __meminit
kernel_physical_mapping_remove(unsigned long start,unsigned long end)1251 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1252 {
1253 start = (unsigned long)__va(start);
1254 end = (unsigned long)__va(end);
1255
1256 remove_pagetable(start, end, true, NULL);
1257 }
1258
arch_remove_memory(u64 start,u64 size,struct vmem_altmap * altmap)1259 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
1260 {
1261 unsigned long start_pfn = start >> PAGE_SHIFT;
1262 unsigned long nr_pages = size >> PAGE_SHIFT;
1263
1264 __remove_pages(start_pfn, nr_pages, altmap);
1265 kernel_physical_mapping_remove(start, start + size);
1266 }
1267 #endif /* CONFIG_MEMORY_HOTPLUG */
1268
1269 static struct kcore_list kcore_vsyscall;
1270
register_page_bootmem_info(void)1271 static void __init register_page_bootmem_info(void)
1272 {
1273 #if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP)
1274 int i;
1275
1276 for_each_online_node(i)
1277 register_page_bootmem_info_node(NODE_DATA(i));
1278 #endif
1279 }
1280
1281 /*
1282 * Pre-allocates page-table pages for the vmalloc area in the kernel page-table.
1283 * Only the level which needs to be synchronized between all page-tables is
1284 * allocated because the synchronization can be expensive.
1285 */
preallocate_vmalloc_pages(void)1286 static void __init preallocate_vmalloc_pages(void)
1287 {
1288 unsigned long addr;
1289 const char *lvl;
1290
1291 for (addr = VMALLOC_START; addr <= VMALLOC_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1292 pgd_t *pgd = pgd_offset_k(addr);
1293 p4d_t *p4d;
1294 pud_t *pud;
1295
1296 lvl = "p4d";
1297 p4d = p4d_alloc(&init_mm, pgd, addr);
1298 if (!p4d)
1299 goto failed;
1300
1301 if (pgtable_l5_enabled())
1302 continue;
1303
1304 /*
1305 * The goal here is to allocate all possibly required
1306 * hardware page tables pointed to by the top hardware
1307 * level.
1308 *
1309 * On 4-level systems, the P4D layer is folded away and
1310 * the above code does no preallocation. Below, go down
1311 * to the pud _software_ level to ensure the second
1312 * hardware level is allocated on 4-level systems too.
1313 */
1314 lvl = "pud";
1315 pud = pud_alloc(&init_mm, p4d, addr);
1316 if (!pud)
1317 goto failed;
1318 }
1319
1320 return;
1321
1322 failed:
1323
1324 /*
1325 * The pages have to be there now or they will be missing in
1326 * process page-tables later.
1327 */
1328 panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl);
1329 }
1330
mem_init(void)1331 void __init mem_init(void)
1332 {
1333 pci_iommu_alloc();
1334
1335 /* clear_bss() already clear the empty_zero_page */
1336
1337 /* this will put all memory onto the freelists */
1338 memblock_free_all();
1339 after_bootmem = 1;
1340 x86_init.hyper.init_after_bootmem();
1341
1342 /*
1343 * Must be done after boot memory is put on freelist, because here we
1344 * might set fields in deferred struct pages that have not yet been
1345 * initialized, and memblock_free_all() initializes all the reserved
1346 * deferred pages for us.
1347 */
1348 register_page_bootmem_info();
1349
1350 /* Register memory areas for /proc/kcore */
1351 if (get_gate_vma(&init_mm))
1352 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
1353
1354 preallocate_vmalloc_pages();
1355 }
1356
1357 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
deferred_page_init_max_threads(const struct cpumask * node_cpumask)1358 int __init deferred_page_init_max_threads(const struct cpumask *node_cpumask)
1359 {
1360 /*
1361 * More CPUs always led to greater speedups on tested systems, up to
1362 * all the nodes' CPUs. Use all since the system is otherwise idle
1363 * now.
1364 */
1365 return max_t(int, cpumask_weight(node_cpumask), 1);
1366 }
1367 #endif
1368
1369 int kernel_set_to_readonly;
1370
mark_rodata_ro(void)1371 void mark_rodata_ro(void)
1372 {
1373 unsigned long start = PFN_ALIGN(_text);
1374 unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1375 unsigned long end = (unsigned long)__end_rodata_hpage_align;
1376 unsigned long text_end = PFN_ALIGN(_etext);
1377 unsigned long rodata_end = PFN_ALIGN(__end_rodata);
1378 unsigned long all_end;
1379
1380 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1381 (end - start) >> 10);
1382 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1383
1384 kernel_set_to_readonly = 1;
1385
1386 /*
1387 * The rodata/data/bss/brk section (but not the kernel text!)
1388 * should also be not-executable.
1389 *
1390 * We align all_end to PMD_SIZE because the existing mapping
1391 * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1392 * split the PMD and the reminder between _brk_end and the end
1393 * of the PMD will remain mapped executable.
1394 *
1395 * Any PMD which was setup after the one which covers _brk_end
1396 * has been zapped already via cleanup_highmem().
1397 */
1398 all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1399 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1400
1401 set_ftrace_ops_ro();
1402
1403 #ifdef CONFIG_CPA_DEBUG
1404 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1405 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1406
1407 printk(KERN_INFO "Testing CPA: again\n");
1408 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1409 #endif
1410
1411 free_kernel_image_pages("unused kernel image (text/rodata gap)",
1412 (void *)text_end, (void *)rodata_start);
1413 free_kernel_image_pages("unused kernel image (rodata/data gap)",
1414 (void *)rodata_end, (void *)_sdata);
1415
1416 debug_checkwx();
1417 }
1418
kern_addr_valid(unsigned long addr)1419 int kern_addr_valid(unsigned long addr)
1420 {
1421 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1422 pgd_t *pgd;
1423 p4d_t *p4d;
1424 pud_t *pud;
1425 pmd_t *pmd;
1426 pte_t *pte;
1427
1428 if (above != 0 && above != -1UL)
1429 return 0;
1430
1431 pgd = pgd_offset_k(addr);
1432 if (pgd_none(*pgd))
1433 return 0;
1434
1435 p4d = p4d_offset(pgd, addr);
1436 if (!p4d_present(*p4d))
1437 return 0;
1438
1439 pud = pud_offset(p4d, addr);
1440 if (!pud_present(*pud))
1441 return 0;
1442
1443 if (pud_large(*pud))
1444 return pfn_valid(pud_pfn(*pud));
1445
1446 pmd = pmd_offset(pud, addr);
1447 if (!pmd_present(*pmd))
1448 return 0;
1449
1450 if (pmd_large(*pmd))
1451 return pfn_valid(pmd_pfn(*pmd));
1452
1453 pte = pte_offset_kernel(pmd, addr);
1454 if (pte_none(*pte))
1455 return 0;
1456
1457 return pfn_valid(pte_pfn(*pte));
1458 }
1459
1460 /*
1461 * Block size is the minimum amount of memory which can be hotplugged or
1462 * hotremoved. It must be power of two and must be equal or larger than
1463 * MIN_MEMORY_BLOCK_SIZE.
1464 */
1465 #define MAX_BLOCK_SIZE (2UL << 30)
1466
1467 /* Amount of ram needed to start using large blocks */
1468 #define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30)
1469
1470 /* Adjustable memory block size */
1471 static unsigned long set_memory_block_size;
set_memory_block_size_order(unsigned int order)1472 int __init set_memory_block_size_order(unsigned int order)
1473 {
1474 unsigned long size = 1UL << order;
1475
1476 if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE)
1477 return -EINVAL;
1478
1479 set_memory_block_size = size;
1480 return 0;
1481 }
1482
probe_memory_block_size(void)1483 static unsigned long probe_memory_block_size(void)
1484 {
1485 unsigned long boot_mem_end = max_pfn << PAGE_SHIFT;
1486 unsigned long bz;
1487
1488 /* If memory block size has been set, then use it */
1489 bz = set_memory_block_size;
1490 if (bz)
1491 goto done;
1492
1493 /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */
1494 if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) {
1495 bz = MIN_MEMORY_BLOCK_SIZE;
1496 goto done;
1497 }
1498
1499 /*
1500 * Use max block size to minimize overhead on bare metal, where
1501 * alignment for memory hotplug isn't a concern.
1502 */
1503 if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
1504 bz = MAX_BLOCK_SIZE;
1505 goto done;
1506 }
1507
1508 /* Find the largest allowed block size that aligns to memory end */
1509 for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) {
1510 if (IS_ALIGNED(boot_mem_end, bz))
1511 break;
1512 }
1513 done:
1514 pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1515
1516 return bz;
1517 }
1518
1519 static unsigned long memory_block_size_probed;
memory_block_size_bytes(void)1520 unsigned long memory_block_size_bytes(void)
1521 {
1522 if (!memory_block_size_probed)
1523 memory_block_size_probed = probe_memory_block_size();
1524
1525 return memory_block_size_probed;
1526 }
1527
1528 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1529 /*
1530 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1531 */
1532 static long __meminitdata addr_start, addr_end;
1533 static void __meminitdata *p_start, *p_end;
1534 static int __meminitdata node_start;
1535
vmemmap_populate_hugepages(unsigned long start,unsigned long end,int node,struct vmem_altmap * altmap)1536 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1537 unsigned long end, int node, struct vmem_altmap *altmap)
1538 {
1539 unsigned long addr;
1540 unsigned long next;
1541 pgd_t *pgd;
1542 p4d_t *p4d;
1543 pud_t *pud;
1544 pmd_t *pmd;
1545
1546 for (addr = start; addr < end; addr = next) {
1547 next = pmd_addr_end(addr, end);
1548
1549 pgd = vmemmap_pgd_populate(addr, node);
1550 if (!pgd)
1551 return -ENOMEM;
1552
1553 p4d = vmemmap_p4d_populate(pgd, addr, node);
1554 if (!p4d)
1555 return -ENOMEM;
1556
1557 pud = vmemmap_pud_populate(p4d, addr, node);
1558 if (!pud)
1559 return -ENOMEM;
1560
1561 pmd = pmd_offset(pud, addr);
1562 if (pmd_none(*pmd)) {
1563 void *p;
1564
1565 p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
1566 if (p) {
1567 pte_t entry;
1568
1569 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1570 PAGE_KERNEL_LARGE);
1571 set_pmd(pmd, __pmd(pte_val(entry)));
1572
1573 /* check to see if we have contiguous blocks */
1574 if (p_end != p || node_start != node) {
1575 if (p_start)
1576 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1577 addr_start, addr_end-1, p_start, p_end-1, node_start);
1578 addr_start = addr;
1579 node_start = node;
1580 p_start = p;
1581 }
1582
1583 addr_end = addr + PMD_SIZE;
1584 p_end = p + PMD_SIZE;
1585
1586 if (!IS_ALIGNED(addr, PMD_SIZE) ||
1587 !IS_ALIGNED(next, PMD_SIZE))
1588 vmemmap_use_new_sub_pmd(addr, next);
1589
1590 continue;
1591 } else if (altmap)
1592 return -ENOMEM; /* no fallback */
1593 } else if (pmd_large(*pmd)) {
1594 vmemmap_verify((pte_t *)pmd, node, addr, next);
1595 vmemmap_use_sub_pmd(addr, next);
1596 continue;
1597 }
1598 if (vmemmap_populate_basepages(addr, next, node, NULL))
1599 return -ENOMEM;
1600 }
1601 return 0;
1602 }
1603
vmemmap_populate(unsigned long start,unsigned long end,int node,struct vmem_altmap * altmap)1604 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1605 struct vmem_altmap *altmap)
1606 {
1607 int err;
1608
1609 VM_BUG_ON(!IS_ALIGNED(start, PAGE_SIZE));
1610 VM_BUG_ON(!IS_ALIGNED(end, PAGE_SIZE));
1611
1612 if (end - start < PAGES_PER_SECTION * sizeof(struct page))
1613 err = vmemmap_populate_basepages(start, end, node, NULL);
1614 else if (boot_cpu_has(X86_FEATURE_PSE))
1615 err = vmemmap_populate_hugepages(start, end, node, altmap);
1616 else if (altmap) {
1617 pr_err_once("%s: no cpu support for altmap allocations\n",
1618 __func__);
1619 err = -ENOMEM;
1620 } else
1621 err = vmemmap_populate_basepages(start, end, node, NULL);
1622 if (!err)
1623 sync_global_pgds(start, end - 1);
1624 return err;
1625 }
1626
1627 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
register_page_bootmem_memmap(unsigned long section_nr,struct page * start_page,unsigned long nr_pages)1628 void register_page_bootmem_memmap(unsigned long section_nr,
1629 struct page *start_page, unsigned long nr_pages)
1630 {
1631 unsigned long addr = (unsigned long)start_page;
1632 unsigned long end = (unsigned long)(start_page + nr_pages);
1633 unsigned long next;
1634 pgd_t *pgd;
1635 p4d_t *p4d;
1636 pud_t *pud;
1637 pmd_t *pmd;
1638 unsigned int nr_pmd_pages;
1639 struct page *page;
1640
1641 for (; addr < end; addr = next) {
1642 pte_t *pte = NULL;
1643
1644 pgd = pgd_offset_k(addr);
1645 if (pgd_none(*pgd)) {
1646 next = (addr + PAGE_SIZE) & PAGE_MASK;
1647 continue;
1648 }
1649 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1650
1651 p4d = p4d_offset(pgd, addr);
1652 if (p4d_none(*p4d)) {
1653 next = (addr + PAGE_SIZE) & PAGE_MASK;
1654 continue;
1655 }
1656 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
1657
1658 pud = pud_offset(p4d, addr);
1659 if (pud_none(*pud)) {
1660 next = (addr + PAGE_SIZE) & PAGE_MASK;
1661 continue;
1662 }
1663 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1664
1665 if (!boot_cpu_has(X86_FEATURE_PSE)) {
1666 next = (addr + PAGE_SIZE) & PAGE_MASK;
1667 pmd = pmd_offset(pud, addr);
1668 if (pmd_none(*pmd))
1669 continue;
1670 get_page_bootmem(section_nr, pmd_page(*pmd),
1671 MIX_SECTION_INFO);
1672
1673 pte = pte_offset_kernel(pmd, addr);
1674 if (pte_none(*pte))
1675 continue;
1676 get_page_bootmem(section_nr, pte_page(*pte),
1677 SECTION_INFO);
1678 } else {
1679 next = pmd_addr_end(addr, end);
1680
1681 pmd = pmd_offset(pud, addr);
1682 if (pmd_none(*pmd))
1683 continue;
1684
1685 nr_pmd_pages = 1 << get_order(PMD_SIZE);
1686 page = pmd_page(*pmd);
1687 while (nr_pmd_pages--)
1688 get_page_bootmem(section_nr, page++,
1689 SECTION_INFO);
1690 }
1691 }
1692 }
1693 #endif
1694
vmemmap_populate_print_last(void)1695 void __meminit vmemmap_populate_print_last(void)
1696 {
1697 if (p_start) {
1698 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1699 addr_start, addr_end-1, p_start, p_end-1, node_start);
1700 p_start = NULL;
1701 p_end = NULL;
1702 node_start = 0;
1703 }
1704 }
1705 #endif
1706