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[mirror_ubuntu-artful-kernel.git] / arch / x86 / mm / init_64.c
1 /*
2 * linux/arch/x86_64/mm/init.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 * Copyright (C) 2000 Pavel Machek <pavel@ucw.cz>
6 * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
7 */
8
9 #include <linux/signal.h>
10 #include <linux/sched.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/ptrace.h>
16 #include <linux/mman.h>
17 #include <linux/mm.h>
18 #include <linux/swap.h>
19 #include <linux/smp.h>
20 #include <linux/init.h>
21 #include <linux/initrd.h>
22 #include <linux/pagemap.h>
23 #include <linux/bootmem.h>
24 #include <linux/memblock.h>
25 #include <linux/proc_fs.h>
26 #include <linux/pci.h>
27 #include <linux/pfn.h>
28 #include <linux/poison.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/module.h>
31 #include <linux/memory.h>
32 #include <linux/memory_hotplug.h>
33 #include <linux/nmi.h>
34 #include <linux/gfp.h>
35 #include <linux/kcore.h>
36
37 #include <asm/processor.h>
38 #include <asm/bios_ebda.h>
39 #include <asm/uaccess.h>
40 #include <asm/pgtable.h>
41 #include <asm/pgalloc.h>
42 #include <asm/dma.h>
43 #include <asm/fixmap.h>
44 #include <asm/e820.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/cacheflush.h>
54 #include <asm/init.h>
55 #include <asm/setup.h>
56
57 #include "mm_internal.h"
58
59 static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
60 unsigned long addr, unsigned long end)
61 {
62 addr &= PMD_MASK;
63 for (; addr < end; addr += PMD_SIZE) {
64 pmd_t *pmd = pmd_page + pmd_index(addr);
65
66 if (!pmd_present(*pmd))
67 set_pmd(pmd, __pmd(addr | pmd_flag));
68 }
69 }
70 static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
71 unsigned long addr, unsigned long end)
72 {
73 unsigned long next;
74
75 for (; addr < end; addr = next) {
76 pud_t *pud = pud_page + pud_index(addr);
77 pmd_t *pmd;
78
79 next = (addr & PUD_MASK) + PUD_SIZE;
80 if (next > end)
81 next = end;
82
83 if (pud_present(*pud)) {
84 pmd = pmd_offset(pud, 0);
85 ident_pmd_init(info->pmd_flag, pmd, addr, next);
86 continue;
87 }
88 pmd = (pmd_t *)info->alloc_pgt_page(info->context);
89 if (!pmd)
90 return -ENOMEM;
91 ident_pmd_init(info->pmd_flag, pmd, addr, next);
92 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
93 }
94
95 return 0;
96 }
97
98 int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
99 unsigned long addr, unsigned long end)
100 {
101 unsigned long next;
102 int result;
103 int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
104
105 for (; addr < end; addr = next) {
106 pgd_t *pgd = pgd_page + pgd_index(addr) + off;
107 pud_t *pud;
108
109 next = (addr & PGDIR_MASK) + PGDIR_SIZE;
110 if (next > end)
111 next = end;
112
113 if (pgd_present(*pgd)) {
114 pud = pud_offset(pgd, 0);
115 result = ident_pud_init(info, pud, addr, next);
116 if (result)
117 return result;
118 continue;
119 }
120
121 pud = (pud_t *)info->alloc_pgt_page(info->context);
122 if (!pud)
123 return -ENOMEM;
124 result = ident_pud_init(info, pud, addr, next);
125 if (result)
126 return result;
127 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
128 }
129
130 return 0;
131 }
132
133 /*
134 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
135 * physical space so we can cache the place of the first one and move
136 * around without checking the pgd every time.
137 */
138
139 pteval_t __supported_pte_mask __read_mostly = ~0;
140 EXPORT_SYMBOL_GPL(__supported_pte_mask);
141
142 int force_personality32;
143
144 /*
145 * noexec32=on|off
146 * Control non executable heap for 32bit processes.
147 * To control the stack too use noexec=off
148 *
149 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
150 * off PROT_READ implies PROT_EXEC
151 */
152 static int __init nonx32_setup(char *str)
153 {
154 if (!strcmp(str, "on"))
155 force_personality32 &= ~READ_IMPLIES_EXEC;
156 else if (!strcmp(str, "off"))
157 force_personality32 |= READ_IMPLIES_EXEC;
158 return 1;
159 }
160 __setup("noexec32=", nonx32_setup);
161
162 /*
163 * When memory was added/removed make sure all the processes MM have
164 * suitable PGD entries in the local PGD level page.
165 */
166 void sync_global_pgds(unsigned long start, unsigned long end, int removed)
167 {
168 unsigned long address;
169
170 for (address = start; address <= end; address += PGDIR_SIZE) {
171 const pgd_t *pgd_ref = pgd_offset_k(address);
172 struct page *page;
173
174 /*
175 * When it is called after memory hot remove, pgd_none()
176 * returns true. In this case (removed == 1), we must clear
177 * the PGD entries in the local PGD level page.
178 */
179 if (pgd_none(*pgd_ref) && !removed)
180 continue;
181
182 spin_lock(&pgd_lock);
183 list_for_each_entry(page, &pgd_list, lru) {
184 pgd_t *pgd;
185 spinlock_t *pgt_lock;
186
187 pgd = (pgd_t *)page_address(page) + pgd_index(address);
188 /* the pgt_lock only for Xen */
189 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
190 spin_lock(pgt_lock);
191
192 if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
193 BUG_ON(pgd_page_vaddr(*pgd)
194 != pgd_page_vaddr(*pgd_ref));
195
196 if (removed) {
197 if (pgd_none(*pgd_ref) && !pgd_none(*pgd))
198 pgd_clear(pgd);
199 } else {
200 if (pgd_none(*pgd))
201 set_pgd(pgd, *pgd_ref);
202 }
203
204 spin_unlock(pgt_lock);
205 }
206 spin_unlock(&pgd_lock);
207 }
208 }
209
210 /*
211 * NOTE: This function is marked __ref because it calls __init function
212 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
213 */
214 static __ref void *spp_getpage(void)
215 {
216 void *ptr;
217
218 if (after_bootmem)
219 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
220 else
221 ptr = alloc_bootmem_pages(PAGE_SIZE);
222
223 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
224 panic("set_pte_phys: cannot allocate page data %s\n",
225 after_bootmem ? "after bootmem" : "");
226 }
227
228 pr_debug("spp_getpage %p\n", ptr);
229
230 return ptr;
231 }
232
233 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
234 {
235 if (pgd_none(*pgd)) {
236 pud_t *pud = (pud_t *)spp_getpage();
237 pgd_populate(&init_mm, pgd, pud);
238 if (pud != pud_offset(pgd, 0))
239 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
240 pud, pud_offset(pgd, 0));
241 }
242 return pud_offset(pgd, vaddr);
243 }
244
245 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
246 {
247 if (pud_none(*pud)) {
248 pmd_t *pmd = (pmd_t *) spp_getpage();
249 pud_populate(&init_mm, pud, pmd);
250 if (pmd != pmd_offset(pud, 0))
251 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
252 pmd, pmd_offset(pud, 0));
253 }
254 return pmd_offset(pud, vaddr);
255 }
256
257 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
258 {
259 if (pmd_none(*pmd)) {
260 pte_t *pte = (pte_t *) spp_getpage();
261 pmd_populate_kernel(&init_mm, pmd, pte);
262 if (pte != pte_offset_kernel(pmd, 0))
263 printk(KERN_ERR "PAGETABLE BUG #02!\n");
264 }
265 return pte_offset_kernel(pmd, vaddr);
266 }
267
268 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
269 {
270 pud_t *pud;
271 pmd_t *pmd;
272 pte_t *pte;
273
274 pud = pud_page + pud_index(vaddr);
275 pmd = fill_pmd(pud, vaddr);
276 pte = fill_pte(pmd, vaddr);
277
278 set_pte(pte, new_pte);
279
280 /*
281 * It's enough to flush this one mapping.
282 * (PGE mappings get flushed as well)
283 */
284 __flush_tlb_one(vaddr);
285 }
286
287 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
288 {
289 pgd_t *pgd;
290 pud_t *pud_page;
291
292 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
293
294 pgd = pgd_offset_k(vaddr);
295 if (pgd_none(*pgd)) {
296 printk(KERN_ERR
297 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
298 return;
299 }
300 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
301 set_pte_vaddr_pud(pud_page, vaddr, pteval);
302 }
303
304 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
305 {
306 pgd_t *pgd;
307 pud_t *pud;
308
309 pgd = pgd_offset_k(vaddr);
310 pud = fill_pud(pgd, vaddr);
311 return fill_pmd(pud, vaddr);
312 }
313
314 pte_t * __init populate_extra_pte(unsigned long vaddr)
315 {
316 pmd_t *pmd;
317
318 pmd = populate_extra_pmd(vaddr);
319 return fill_pte(pmd, vaddr);
320 }
321
322 /*
323 * Create large page table mappings for a range of physical addresses.
324 */
325 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
326 enum page_cache_mode cache)
327 {
328 pgd_t *pgd;
329 pud_t *pud;
330 pmd_t *pmd;
331 pgprot_t prot;
332
333 pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
334 pgprot_val(pgprot_4k_2_large(cachemode2pgprot(cache)));
335 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
336 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
337 pgd = pgd_offset_k((unsigned long)__va(phys));
338 if (pgd_none(*pgd)) {
339 pud = (pud_t *) spp_getpage();
340 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
341 _PAGE_USER));
342 }
343 pud = pud_offset(pgd, (unsigned long)__va(phys));
344 if (pud_none(*pud)) {
345 pmd = (pmd_t *) spp_getpage();
346 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
347 _PAGE_USER));
348 }
349 pmd = pmd_offset(pud, phys);
350 BUG_ON(!pmd_none(*pmd));
351 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
352 }
353 }
354
355 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
356 {
357 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
358 }
359
360 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
361 {
362 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
363 }
364
365 /*
366 * The head.S code sets up the kernel high mapping:
367 *
368 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
369 *
370 * phys_base holds the negative offset to the kernel, which is added
371 * to the compile time generated pmds. This results in invalid pmds up
372 * to the point where we hit the physaddr 0 mapping.
373 *
374 * We limit the mappings to the region from _text to _brk_end. _brk_end
375 * is rounded up to the 2MB boundary. This catches the invalid pmds as
376 * well, as they are located before _text:
377 */
378 void __init cleanup_highmap(void)
379 {
380 unsigned long vaddr = __START_KERNEL_map;
381 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
382 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
383 pmd_t *pmd = level2_kernel_pgt;
384
385 /*
386 * Native path, max_pfn_mapped is not set yet.
387 * Xen has valid max_pfn_mapped set in
388 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
389 */
390 if (max_pfn_mapped)
391 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
392
393 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
394 if (pmd_none(*pmd))
395 continue;
396 if (vaddr < (unsigned long) _text || vaddr > end)
397 set_pmd(pmd, __pmd(0));
398 }
399 }
400
401 static unsigned long __meminit
402 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
403 pgprot_t prot)
404 {
405 unsigned long pages = 0, next;
406 unsigned long last_map_addr = end;
407 int i;
408
409 pte_t *pte = pte_page + pte_index(addr);
410
411 for (i = pte_index(addr); i < PTRS_PER_PTE; i++, addr = next, pte++) {
412 next = (addr & PAGE_MASK) + PAGE_SIZE;
413 if (addr >= end) {
414 if (!after_bootmem &&
415 !e820_any_mapped(addr & PAGE_MASK, next, E820_RAM) &&
416 !e820_any_mapped(addr & PAGE_MASK, next, E820_RESERVED_KERN))
417 set_pte(pte, __pte(0));
418 continue;
419 }
420
421 /*
422 * We will re-use the existing mapping.
423 * Xen for example has some special requirements, like mapping
424 * pagetable pages as RO. So assume someone who pre-setup
425 * these mappings are more intelligent.
426 */
427 if (pte_val(*pte)) {
428 if (!after_bootmem)
429 pages++;
430 continue;
431 }
432
433 if (0)
434 printk(" pte=%p addr=%lx pte=%016lx\n",
435 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
436 pages++;
437 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
438 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
439 }
440
441 update_page_count(PG_LEVEL_4K, pages);
442
443 return last_map_addr;
444 }
445
446 static unsigned long __meminit
447 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
448 unsigned long page_size_mask, pgprot_t prot)
449 {
450 unsigned long pages = 0, next;
451 unsigned long last_map_addr = end;
452
453 int i = pmd_index(address);
454
455 for (; i < PTRS_PER_PMD; i++, address = next) {
456 pmd_t *pmd = pmd_page + pmd_index(address);
457 pte_t *pte;
458 pgprot_t new_prot = prot;
459
460 next = (address & PMD_MASK) + PMD_SIZE;
461 if (address >= end) {
462 if (!after_bootmem &&
463 !e820_any_mapped(address & PMD_MASK, next, E820_RAM) &&
464 !e820_any_mapped(address & PMD_MASK, next, E820_RESERVED_KERN))
465 set_pmd(pmd, __pmd(0));
466 continue;
467 }
468
469 if (pmd_val(*pmd)) {
470 if (!pmd_large(*pmd)) {
471 spin_lock(&init_mm.page_table_lock);
472 pte = (pte_t *)pmd_page_vaddr(*pmd);
473 last_map_addr = phys_pte_init(pte, address,
474 end, prot);
475 spin_unlock(&init_mm.page_table_lock);
476 continue;
477 }
478 /*
479 * If we are ok with PG_LEVEL_2M mapping, then we will
480 * use the existing mapping,
481 *
482 * Otherwise, we will split the large page mapping but
483 * use the same existing protection bits except for
484 * large page, so that we don't violate Intel's TLB
485 * Application note (317080) which says, while changing
486 * the page sizes, new and old translations should
487 * not differ with respect to page frame and
488 * attributes.
489 */
490 if (page_size_mask & (1 << PG_LEVEL_2M)) {
491 if (!after_bootmem)
492 pages++;
493 last_map_addr = next;
494 continue;
495 }
496 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
497 }
498
499 if (page_size_mask & (1<<PG_LEVEL_2M)) {
500 pages++;
501 spin_lock(&init_mm.page_table_lock);
502 set_pte((pte_t *)pmd,
503 pfn_pte((address & PMD_MASK) >> PAGE_SHIFT,
504 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
505 spin_unlock(&init_mm.page_table_lock);
506 last_map_addr = next;
507 continue;
508 }
509
510 pte = alloc_low_page();
511 last_map_addr = phys_pte_init(pte, address, end, new_prot);
512
513 spin_lock(&init_mm.page_table_lock);
514 pmd_populate_kernel(&init_mm, pmd, pte);
515 spin_unlock(&init_mm.page_table_lock);
516 }
517 update_page_count(PG_LEVEL_2M, pages);
518 return last_map_addr;
519 }
520
521 static unsigned long __meminit
522 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
523 unsigned long page_size_mask)
524 {
525 unsigned long pages = 0, next;
526 unsigned long last_map_addr = end;
527 int i = pud_index(addr);
528
529 for (; i < PTRS_PER_PUD; i++, addr = next) {
530 pud_t *pud = pud_page + pud_index(addr);
531 pmd_t *pmd;
532 pgprot_t prot = PAGE_KERNEL;
533
534 next = (addr & PUD_MASK) + PUD_SIZE;
535 if (addr >= end) {
536 if (!after_bootmem &&
537 !e820_any_mapped(addr & PUD_MASK, next, E820_RAM) &&
538 !e820_any_mapped(addr & PUD_MASK, next, E820_RESERVED_KERN))
539 set_pud(pud, __pud(0));
540 continue;
541 }
542
543 if (pud_val(*pud)) {
544 if (!pud_large(*pud)) {
545 pmd = pmd_offset(pud, 0);
546 last_map_addr = phys_pmd_init(pmd, addr, end,
547 page_size_mask, prot);
548 __flush_tlb_all();
549 continue;
550 }
551 /*
552 * If we are ok with PG_LEVEL_1G mapping, then we will
553 * use the existing mapping.
554 *
555 * Otherwise, we will split the gbpage mapping but use
556 * the same existing protection bits except for large
557 * page, so that we don't violate Intel's TLB
558 * Application note (317080) which says, while changing
559 * the page sizes, new and old translations should
560 * not differ with respect to page frame and
561 * attributes.
562 */
563 if (page_size_mask & (1 << PG_LEVEL_1G)) {
564 if (!after_bootmem)
565 pages++;
566 last_map_addr = next;
567 continue;
568 }
569 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
570 }
571
572 if (page_size_mask & (1<<PG_LEVEL_1G)) {
573 pages++;
574 spin_lock(&init_mm.page_table_lock);
575 set_pte((pte_t *)pud,
576 pfn_pte((addr & PUD_MASK) >> PAGE_SHIFT,
577 PAGE_KERNEL_LARGE));
578 spin_unlock(&init_mm.page_table_lock);
579 last_map_addr = next;
580 continue;
581 }
582
583 pmd = alloc_low_page();
584 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
585 prot);
586
587 spin_lock(&init_mm.page_table_lock);
588 pud_populate(&init_mm, pud, pmd);
589 spin_unlock(&init_mm.page_table_lock);
590 }
591 __flush_tlb_all();
592
593 update_page_count(PG_LEVEL_1G, pages);
594
595 return last_map_addr;
596 }
597
598 unsigned long __meminit
599 kernel_physical_mapping_init(unsigned long start,
600 unsigned long end,
601 unsigned long page_size_mask)
602 {
603 bool pgd_changed = false;
604 unsigned long next, last_map_addr = end;
605 unsigned long addr;
606
607 start = (unsigned long)__va(start);
608 end = (unsigned long)__va(end);
609 addr = start;
610
611 for (; start < end; start = next) {
612 pgd_t *pgd = pgd_offset_k(start);
613 pud_t *pud;
614
615 next = (start & PGDIR_MASK) + PGDIR_SIZE;
616
617 if (pgd_val(*pgd)) {
618 pud = (pud_t *)pgd_page_vaddr(*pgd);
619 last_map_addr = phys_pud_init(pud, __pa(start),
620 __pa(end), page_size_mask);
621 continue;
622 }
623
624 pud = alloc_low_page();
625 last_map_addr = phys_pud_init(pud, __pa(start), __pa(end),
626 page_size_mask);
627
628 spin_lock(&init_mm.page_table_lock);
629 pgd_populate(&init_mm, pgd, pud);
630 spin_unlock(&init_mm.page_table_lock);
631 pgd_changed = true;
632 }
633
634 if (pgd_changed)
635 sync_global_pgds(addr, end - 1, 0);
636
637 __flush_tlb_all();
638
639 return last_map_addr;
640 }
641
642 #ifndef CONFIG_NUMA
643 void __init initmem_init(void)
644 {
645 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
646 }
647 #endif
648
649 void __init paging_init(void)
650 {
651 sparse_memory_present_with_active_regions(MAX_NUMNODES);
652 sparse_init();
653
654 /*
655 * clear the default setting with node 0
656 * note: don't use nodes_clear here, that is really clearing when
657 * numa support is not compiled in, and later node_set_state
658 * will not set it back.
659 */
660 node_clear_state(0, N_MEMORY);
661 if (N_MEMORY != N_NORMAL_MEMORY)
662 node_clear_state(0, N_NORMAL_MEMORY);
663
664 zone_sizes_init();
665 }
666
667 /*
668 * Memory hotplug specific functions
669 */
670 #ifdef CONFIG_MEMORY_HOTPLUG
671 /*
672 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
673 * updating.
674 */
675 static void update_end_of_memory_vars(u64 start, u64 size)
676 {
677 unsigned long end_pfn = PFN_UP(start + size);
678
679 if (end_pfn > max_pfn) {
680 max_pfn = end_pfn;
681 max_low_pfn = end_pfn;
682 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
683 }
684 }
685
686 /*
687 * Memory is added always to NORMAL zone. This means you will never get
688 * additional DMA/DMA32 memory.
689 */
690 int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
691 {
692 struct pglist_data *pgdat = NODE_DATA(nid);
693 struct zone *zone = pgdat->node_zones +
694 zone_for_memory(nid, start, size, ZONE_NORMAL, for_device);
695 unsigned long start_pfn = start >> PAGE_SHIFT;
696 unsigned long nr_pages = size >> PAGE_SHIFT;
697 int ret;
698
699 init_memory_mapping(start, start + size);
700
701 ret = __add_pages(nid, zone, start_pfn, nr_pages);
702 WARN_ON_ONCE(ret);
703
704 /* update max_pfn, max_low_pfn and high_memory */
705 update_end_of_memory_vars(start, size);
706
707 return ret;
708 }
709 EXPORT_SYMBOL_GPL(arch_add_memory);
710
711 #define PAGE_INUSE 0xFD
712
713 static void __meminit free_pagetable(struct page *page, int order)
714 {
715 unsigned long magic;
716 unsigned int nr_pages = 1 << order;
717
718 /* bootmem page has reserved flag */
719 if (PageReserved(page)) {
720 __ClearPageReserved(page);
721
722 magic = (unsigned long)page->lru.next;
723 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
724 while (nr_pages--)
725 put_page_bootmem(page++);
726 } else
727 while (nr_pages--)
728 free_reserved_page(page++);
729 } else
730 free_pages((unsigned long)page_address(page), order);
731 }
732
733 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
734 {
735 pte_t *pte;
736 int i;
737
738 for (i = 0; i < PTRS_PER_PTE; i++) {
739 pte = pte_start + i;
740 if (pte_val(*pte))
741 return;
742 }
743
744 /* free a pte talbe */
745 free_pagetable(pmd_page(*pmd), 0);
746 spin_lock(&init_mm.page_table_lock);
747 pmd_clear(pmd);
748 spin_unlock(&init_mm.page_table_lock);
749 }
750
751 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
752 {
753 pmd_t *pmd;
754 int i;
755
756 for (i = 0; i < PTRS_PER_PMD; i++) {
757 pmd = pmd_start + i;
758 if (pmd_val(*pmd))
759 return;
760 }
761
762 /* free a pmd talbe */
763 free_pagetable(pud_page(*pud), 0);
764 spin_lock(&init_mm.page_table_lock);
765 pud_clear(pud);
766 spin_unlock(&init_mm.page_table_lock);
767 }
768
769 /* Return true if pgd is changed, otherwise return false. */
770 static bool __meminit free_pud_table(pud_t *pud_start, pgd_t *pgd)
771 {
772 pud_t *pud;
773 int i;
774
775 for (i = 0; i < PTRS_PER_PUD; i++) {
776 pud = pud_start + i;
777 if (pud_val(*pud))
778 return false;
779 }
780
781 /* free a pud table */
782 free_pagetable(pgd_page(*pgd), 0);
783 spin_lock(&init_mm.page_table_lock);
784 pgd_clear(pgd);
785 spin_unlock(&init_mm.page_table_lock);
786
787 return true;
788 }
789
790 static void __meminit
791 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
792 bool direct)
793 {
794 unsigned long next, pages = 0;
795 pte_t *pte;
796 void *page_addr;
797 phys_addr_t phys_addr;
798
799 pte = pte_start + pte_index(addr);
800 for (; addr < end; addr = next, pte++) {
801 next = (addr + PAGE_SIZE) & PAGE_MASK;
802 if (next > end)
803 next = end;
804
805 if (!pte_present(*pte))
806 continue;
807
808 /*
809 * We mapped [0,1G) memory as identity mapping when
810 * initializing, in arch/x86/kernel/head_64.S. These
811 * pagetables cannot be removed.
812 */
813 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
814 if (phys_addr < (phys_addr_t)0x40000000)
815 return;
816
817 if (PAGE_ALIGNED(addr) && PAGE_ALIGNED(next)) {
818 /*
819 * Do not free direct mapping pages since they were
820 * freed when offlining, or simplely not in use.
821 */
822 if (!direct)
823 free_pagetable(pte_page(*pte), 0);
824
825 spin_lock(&init_mm.page_table_lock);
826 pte_clear(&init_mm, addr, pte);
827 spin_unlock(&init_mm.page_table_lock);
828
829 /* For non-direct mapping, pages means nothing. */
830 pages++;
831 } else {
832 /*
833 * If we are here, we are freeing vmemmap pages since
834 * direct mapped memory ranges to be freed are aligned.
835 *
836 * If we are not removing the whole page, it means
837 * other page structs in this page are being used and
838 * we canot remove them. So fill the unused page_structs
839 * with 0xFD, and remove the page when it is wholly
840 * filled with 0xFD.
841 */
842 memset((void *)addr, PAGE_INUSE, next - addr);
843
844 page_addr = page_address(pte_page(*pte));
845 if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
846 free_pagetable(pte_page(*pte), 0);
847
848 spin_lock(&init_mm.page_table_lock);
849 pte_clear(&init_mm, addr, pte);
850 spin_unlock(&init_mm.page_table_lock);
851 }
852 }
853 }
854
855 /* Call free_pte_table() in remove_pmd_table(). */
856 flush_tlb_all();
857 if (direct)
858 update_page_count(PG_LEVEL_4K, -pages);
859 }
860
861 static void __meminit
862 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
863 bool direct)
864 {
865 unsigned long next, pages = 0;
866 pte_t *pte_base;
867 pmd_t *pmd;
868 void *page_addr;
869
870 pmd = pmd_start + pmd_index(addr);
871 for (; addr < end; addr = next, pmd++) {
872 next = pmd_addr_end(addr, end);
873
874 if (!pmd_present(*pmd))
875 continue;
876
877 if (pmd_large(*pmd)) {
878 if (IS_ALIGNED(addr, PMD_SIZE) &&
879 IS_ALIGNED(next, PMD_SIZE)) {
880 if (!direct)
881 free_pagetable(pmd_page(*pmd),
882 get_order(PMD_SIZE));
883
884 spin_lock(&init_mm.page_table_lock);
885 pmd_clear(pmd);
886 spin_unlock(&init_mm.page_table_lock);
887 pages++;
888 } else {
889 /* If here, we are freeing vmemmap pages. */
890 memset((void *)addr, PAGE_INUSE, next - addr);
891
892 page_addr = page_address(pmd_page(*pmd));
893 if (!memchr_inv(page_addr, PAGE_INUSE,
894 PMD_SIZE)) {
895 free_pagetable(pmd_page(*pmd),
896 get_order(PMD_SIZE));
897
898 spin_lock(&init_mm.page_table_lock);
899 pmd_clear(pmd);
900 spin_unlock(&init_mm.page_table_lock);
901 }
902 }
903
904 continue;
905 }
906
907 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
908 remove_pte_table(pte_base, addr, next, direct);
909 free_pte_table(pte_base, pmd);
910 }
911
912 /* Call free_pmd_table() in remove_pud_table(). */
913 if (direct)
914 update_page_count(PG_LEVEL_2M, -pages);
915 }
916
917 static void __meminit
918 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
919 bool direct)
920 {
921 unsigned long next, pages = 0;
922 pmd_t *pmd_base;
923 pud_t *pud;
924 void *page_addr;
925
926 pud = pud_start + pud_index(addr);
927 for (; addr < end; addr = next, pud++) {
928 next = pud_addr_end(addr, end);
929
930 if (!pud_present(*pud))
931 continue;
932
933 if (pud_large(*pud)) {
934 if (IS_ALIGNED(addr, PUD_SIZE) &&
935 IS_ALIGNED(next, PUD_SIZE)) {
936 if (!direct)
937 free_pagetable(pud_page(*pud),
938 get_order(PUD_SIZE));
939
940 spin_lock(&init_mm.page_table_lock);
941 pud_clear(pud);
942 spin_unlock(&init_mm.page_table_lock);
943 pages++;
944 } else {
945 /* If here, we are freeing vmemmap pages. */
946 memset((void *)addr, PAGE_INUSE, next - addr);
947
948 page_addr = page_address(pud_page(*pud));
949 if (!memchr_inv(page_addr, PAGE_INUSE,
950 PUD_SIZE)) {
951 free_pagetable(pud_page(*pud),
952 get_order(PUD_SIZE));
953
954 spin_lock(&init_mm.page_table_lock);
955 pud_clear(pud);
956 spin_unlock(&init_mm.page_table_lock);
957 }
958 }
959
960 continue;
961 }
962
963 pmd_base = (pmd_t *)pud_page_vaddr(*pud);
964 remove_pmd_table(pmd_base, addr, next, direct);
965 free_pmd_table(pmd_base, pud);
966 }
967
968 if (direct)
969 update_page_count(PG_LEVEL_1G, -pages);
970 }
971
972 /* start and end are both virtual address. */
973 static void __meminit
974 remove_pagetable(unsigned long start, unsigned long end, bool direct)
975 {
976 unsigned long next;
977 unsigned long addr;
978 pgd_t *pgd;
979 pud_t *pud;
980 bool pgd_changed = false;
981
982 for (addr = start; addr < end; addr = next) {
983 next = pgd_addr_end(addr, end);
984
985 pgd = pgd_offset_k(addr);
986 if (!pgd_present(*pgd))
987 continue;
988
989 pud = (pud_t *)pgd_page_vaddr(*pgd);
990 remove_pud_table(pud, addr, next, direct);
991 if (free_pud_table(pud, pgd))
992 pgd_changed = true;
993 }
994
995 if (pgd_changed)
996 sync_global_pgds(start, end - 1, 1);
997
998 flush_tlb_all();
999 }
1000
1001 void __ref vmemmap_free(unsigned long start, unsigned long end)
1002 {
1003 remove_pagetable(start, end, false);
1004 }
1005
1006 #ifdef CONFIG_MEMORY_HOTREMOVE
1007 static void __meminit
1008 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1009 {
1010 start = (unsigned long)__va(start);
1011 end = (unsigned long)__va(end);
1012
1013 remove_pagetable(start, end, true);
1014 }
1015
1016 int __ref arch_remove_memory(u64 start, u64 size)
1017 {
1018 unsigned long start_pfn = start >> PAGE_SHIFT;
1019 unsigned long nr_pages = size >> PAGE_SHIFT;
1020 struct zone *zone;
1021 int ret;
1022
1023 zone = page_zone(pfn_to_page(start_pfn));
1024 kernel_physical_mapping_remove(start, start + size);
1025 ret = __remove_pages(zone, start_pfn, nr_pages);
1026 WARN_ON_ONCE(ret);
1027
1028 return ret;
1029 }
1030 #endif
1031 #endif /* CONFIG_MEMORY_HOTPLUG */
1032
1033 static struct kcore_list kcore_vsyscall;
1034
1035 static void __init register_page_bootmem_info(void)
1036 {
1037 #ifdef CONFIG_NUMA
1038 int i;
1039
1040 for_each_online_node(i)
1041 register_page_bootmem_info_node(NODE_DATA(i));
1042 #endif
1043 }
1044
1045 void __init mem_init(void)
1046 {
1047 pci_iommu_alloc();
1048
1049 /* clear_bss() already clear the empty_zero_page */
1050
1051 register_page_bootmem_info();
1052
1053 /* this will put all memory onto the freelists */
1054 free_all_bootmem();
1055 after_bootmem = 1;
1056
1057 /* Register memory areas for /proc/kcore */
1058 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR,
1059 PAGE_SIZE, KCORE_OTHER);
1060
1061 mem_init_print_info(NULL);
1062 }
1063
1064 #ifdef CONFIG_DEBUG_RODATA
1065 const int rodata_test_data = 0xC3;
1066 EXPORT_SYMBOL_GPL(rodata_test_data);
1067
1068 int kernel_set_to_readonly;
1069
1070 void set_kernel_text_rw(void)
1071 {
1072 unsigned long start = PFN_ALIGN(_text);
1073 unsigned long end = PFN_ALIGN(__stop___ex_table);
1074
1075 if (!kernel_set_to_readonly)
1076 return;
1077
1078 pr_debug("Set kernel text: %lx - %lx for read write\n",
1079 start, end);
1080
1081 /*
1082 * Make the kernel identity mapping for text RW. Kernel text
1083 * mapping will always be RO. Refer to the comment in
1084 * static_protections() in pageattr.c
1085 */
1086 set_memory_rw(start, (end - start) >> PAGE_SHIFT);
1087 }
1088
1089 void set_kernel_text_ro(void)
1090 {
1091 unsigned long start = PFN_ALIGN(_text);
1092 unsigned long end = PFN_ALIGN(__stop___ex_table);
1093
1094 if (!kernel_set_to_readonly)
1095 return;
1096
1097 pr_debug("Set kernel text: %lx - %lx for read only\n",
1098 start, end);
1099
1100 /*
1101 * Set the kernel identity mapping for text RO.
1102 */
1103 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1104 }
1105
1106 void mark_rodata_ro(void)
1107 {
1108 unsigned long start = PFN_ALIGN(_text);
1109 unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1110 unsigned long end = (unsigned long) &__end_rodata_hpage_align;
1111 unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
1112 unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
1113 unsigned long all_end;
1114
1115 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1116 (end - start) >> 10);
1117 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1118
1119 kernel_set_to_readonly = 1;
1120
1121 /*
1122 * The rodata/data/bss/brk section (but not the kernel text!)
1123 * should also be not-executable.
1124 *
1125 * We align all_end to PMD_SIZE because the existing mapping
1126 * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1127 * split the PMD and the reminder between _brk_end and the end
1128 * of the PMD will remain mapped executable.
1129 *
1130 * Any PMD which was setup after the one which covers _brk_end
1131 * has been zapped already via cleanup_highmem().
1132 */
1133 all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1134 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1135
1136 rodata_test();
1137
1138 #ifdef CONFIG_CPA_DEBUG
1139 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1140 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1141
1142 printk(KERN_INFO "Testing CPA: again\n");
1143 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1144 #endif
1145
1146 free_init_pages("unused kernel",
1147 (unsigned long) __va(__pa_symbol(text_end)),
1148 (unsigned long) __va(__pa_symbol(rodata_start)));
1149 free_init_pages("unused kernel",
1150 (unsigned long) __va(__pa_symbol(rodata_end)),
1151 (unsigned long) __va(__pa_symbol(_sdata)));
1152
1153 debug_checkwx();
1154 }
1155
1156 #endif
1157
1158 int kern_addr_valid(unsigned long addr)
1159 {
1160 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1161 pgd_t *pgd;
1162 pud_t *pud;
1163 pmd_t *pmd;
1164 pte_t *pte;
1165
1166 if (above != 0 && above != -1UL)
1167 return 0;
1168
1169 pgd = pgd_offset_k(addr);
1170 if (pgd_none(*pgd))
1171 return 0;
1172
1173 pud = pud_offset(pgd, addr);
1174 if (pud_none(*pud))
1175 return 0;
1176
1177 if (pud_large(*pud))
1178 return pfn_valid(pud_pfn(*pud));
1179
1180 pmd = pmd_offset(pud, addr);
1181 if (pmd_none(*pmd))
1182 return 0;
1183
1184 if (pmd_large(*pmd))
1185 return pfn_valid(pmd_pfn(*pmd));
1186
1187 pte = pte_offset_kernel(pmd, addr);
1188 if (pte_none(*pte))
1189 return 0;
1190
1191 return pfn_valid(pte_pfn(*pte));
1192 }
1193
1194 static unsigned long probe_memory_block_size(void)
1195 {
1196 /* start from 2g */
1197 unsigned long bz = 1UL<<31;
1198
1199 if (totalram_pages >= (64ULL << (30 - PAGE_SHIFT))) {
1200 pr_info("Using 2GB memory block size for large-memory system\n");
1201 return 2UL * 1024 * 1024 * 1024;
1202 }
1203
1204 /* less than 64g installed */
1205 if ((max_pfn << PAGE_SHIFT) < (16UL << 32))
1206 return MIN_MEMORY_BLOCK_SIZE;
1207
1208 /* get the tail size */
1209 while (bz > MIN_MEMORY_BLOCK_SIZE) {
1210 if (!((max_pfn << PAGE_SHIFT) & (bz - 1)))
1211 break;
1212 bz >>= 1;
1213 }
1214
1215 printk(KERN_DEBUG "memory block size : %ldMB\n", bz >> 20);
1216
1217 return bz;
1218 }
1219
1220 static unsigned long memory_block_size_probed;
1221 unsigned long memory_block_size_bytes(void)
1222 {
1223 if (!memory_block_size_probed)
1224 memory_block_size_probed = probe_memory_block_size();
1225
1226 return memory_block_size_probed;
1227 }
1228
1229 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1230 /*
1231 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1232 */
1233 static long __meminitdata addr_start, addr_end;
1234 static void __meminitdata *p_start, *p_end;
1235 static int __meminitdata node_start;
1236
1237 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1238 unsigned long end, int node)
1239 {
1240 unsigned long addr;
1241 unsigned long next;
1242 pgd_t *pgd;
1243 pud_t *pud;
1244 pmd_t *pmd;
1245
1246 for (addr = start; addr < end; addr = next) {
1247 next = pmd_addr_end(addr, end);
1248
1249 pgd = vmemmap_pgd_populate(addr, node);
1250 if (!pgd)
1251 return -ENOMEM;
1252
1253 pud = vmemmap_pud_populate(pgd, addr, node);
1254 if (!pud)
1255 return -ENOMEM;
1256
1257 pmd = pmd_offset(pud, addr);
1258 if (pmd_none(*pmd)) {
1259 void *p;
1260
1261 p = vmemmap_alloc_block_buf(PMD_SIZE, node);
1262 if (p) {
1263 pte_t entry;
1264
1265 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1266 PAGE_KERNEL_LARGE);
1267 set_pmd(pmd, __pmd(pte_val(entry)));
1268
1269 /* check to see if we have contiguous blocks */
1270 if (p_end != p || node_start != node) {
1271 if (p_start)
1272 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1273 addr_start, addr_end-1, p_start, p_end-1, node_start);
1274 addr_start = addr;
1275 node_start = node;
1276 p_start = p;
1277 }
1278
1279 addr_end = addr + PMD_SIZE;
1280 p_end = p + PMD_SIZE;
1281 continue;
1282 }
1283 } else if (pmd_large(*pmd)) {
1284 vmemmap_verify((pte_t *)pmd, node, addr, next);
1285 continue;
1286 }
1287 pr_warn_once("vmemmap: falling back to regular page backing\n");
1288 if (vmemmap_populate_basepages(addr, next, node))
1289 return -ENOMEM;
1290 }
1291 return 0;
1292 }
1293
1294 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
1295 {
1296 int err;
1297
1298 if (cpu_has_pse)
1299 err = vmemmap_populate_hugepages(start, end, node);
1300 else
1301 err = vmemmap_populate_basepages(start, end, node);
1302 if (!err)
1303 sync_global_pgds(start, end - 1, 0);
1304 return err;
1305 }
1306
1307 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1308 void register_page_bootmem_memmap(unsigned long section_nr,
1309 struct page *start_page, unsigned long size)
1310 {
1311 unsigned long addr = (unsigned long)start_page;
1312 unsigned long end = (unsigned long)(start_page + size);
1313 unsigned long next;
1314 pgd_t *pgd;
1315 pud_t *pud;
1316 pmd_t *pmd;
1317 unsigned int nr_pages;
1318 struct page *page;
1319
1320 for (; addr < end; addr = next) {
1321 pte_t *pte = NULL;
1322
1323 pgd = pgd_offset_k(addr);
1324 if (pgd_none(*pgd)) {
1325 next = (addr + PAGE_SIZE) & PAGE_MASK;
1326 continue;
1327 }
1328 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1329
1330 pud = pud_offset(pgd, addr);
1331 if (pud_none(*pud)) {
1332 next = (addr + PAGE_SIZE) & PAGE_MASK;
1333 continue;
1334 }
1335 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1336
1337 if (!cpu_has_pse) {
1338 next = (addr + PAGE_SIZE) & PAGE_MASK;
1339 pmd = pmd_offset(pud, addr);
1340 if (pmd_none(*pmd))
1341 continue;
1342 get_page_bootmem(section_nr, pmd_page(*pmd),
1343 MIX_SECTION_INFO);
1344
1345 pte = pte_offset_kernel(pmd, addr);
1346 if (pte_none(*pte))
1347 continue;
1348 get_page_bootmem(section_nr, pte_page(*pte),
1349 SECTION_INFO);
1350 } else {
1351 next = pmd_addr_end(addr, end);
1352
1353 pmd = pmd_offset(pud, addr);
1354 if (pmd_none(*pmd))
1355 continue;
1356
1357 nr_pages = 1 << (get_order(PMD_SIZE));
1358 page = pmd_page(*pmd);
1359 while (nr_pages--)
1360 get_page_bootmem(section_nr, page++,
1361 SECTION_INFO);
1362 }
1363 }
1364 }
1365 #endif
1366
1367 void __meminit vmemmap_populate_print_last(void)
1368 {
1369 if (p_start) {
1370 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1371 addr_start, addr_end-1, p_start, p_end-1, node_start);
1372 p_start = NULL;
1373 p_end = NULL;
1374 node_start = 0;
1375 }
1376 }
1377 #endif