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[mirror_ubuntu-hirsute-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/uv/uv.h>
56 #include <asm/setup.h>
57
58 #include "mm_internal.h"
59
60 static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
61 unsigned long addr, unsigned long end)
62 {
63 addr &= PMD_MASK;
64 for (; addr < end; addr += PMD_SIZE) {
65 pmd_t *pmd = pmd_page + pmd_index(addr);
66
67 if (!pmd_present(*pmd))
68 set_pmd(pmd, __pmd(addr | pmd_flag));
69 }
70 }
71 static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
72 unsigned long addr, unsigned long end)
73 {
74 unsigned long next;
75
76 for (; addr < end; addr = next) {
77 pud_t *pud = pud_page + pud_index(addr);
78 pmd_t *pmd;
79
80 next = (addr & PUD_MASK) + PUD_SIZE;
81 if (next > end)
82 next = end;
83
84 if (pud_present(*pud)) {
85 pmd = pmd_offset(pud, 0);
86 ident_pmd_init(info->pmd_flag, pmd, addr, next);
87 continue;
88 }
89 pmd = (pmd_t *)info->alloc_pgt_page(info->context);
90 if (!pmd)
91 return -ENOMEM;
92 ident_pmd_init(info->pmd_flag, pmd, addr, next);
93 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
94 }
95
96 return 0;
97 }
98
99 int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
100 unsigned long addr, unsigned long end)
101 {
102 unsigned long next;
103 int result;
104 int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
105
106 for (; addr < end; addr = next) {
107 pgd_t *pgd = pgd_page + pgd_index(addr) + off;
108 pud_t *pud;
109
110 next = (addr & PGDIR_MASK) + PGDIR_SIZE;
111 if (next > end)
112 next = end;
113
114 if (pgd_present(*pgd)) {
115 pud = pud_offset(pgd, 0);
116 result = ident_pud_init(info, pud, addr, next);
117 if (result)
118 return result;
119 continue;
120 }
121
122 pud = (pud_t *)info->alloc_pgt_page(info->context);
123 if (!pud)
124 return -ENOMEM;
125 result = ident_pud_init(info, pud, addr, next);
126 if (result)
127 return result;
128 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
129 }
130
131 return 0;
132 }
133
134 static int __init parse_direct_gbpages_off(char *arg)
135 {
136 direct_gbpages = 0;
137 return 0;
138 }
139 early_param("nogbpages", parse_direct_gbpages_off);
140
141 static int __init parse_direct_gbpages_on(char *arg)
142 {
143 direct_gbpages = 1;
144 return 0;
145 }
146 early_param("gbpages", parse_direct_gbpages_on);
147
148 /*
149 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
150 * physical space so we can cache the place of the first one and move
151 * around without checking the pgd every time.
152 */
153
154 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
155 EXPORT_SYMBOL_GPL(__supported_pte_mask);
156
157 int force_personality32;
158
159 /*
160 * noexec32=on|off
161 * Control non executable heap for 32bit processes.
162 * To control the stack too use noexec=off
163 *
164 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
165 * off PROT_READ implies PROT_EXEC
166 */
167 static int __init nonx32_setup(char *str)
168 {
169 if (!strcmp(str, "on"))
170 force_personality32 &= ~READ_IMPLIES_EXEC;
171 else if (!strcmp(str, "off"))
172 force_personality32 |= READ_IMPLIES_EXEC;
173 return 1;
174 }
175 __setup("noexec32=", nonx32_setup);
176
177 /*
178 * When memory was added/removed make sure all the processes MM have
179 * suitable PGD entries in the local PGD level page.
180 */
181 void sync_global_pgds(unsigned long start, unsigned long end)
182 {
183 unsigned long address;
184
185 for (address = start; address <= end; address += PGDIR_SIZE) {
186 const pgd_t *pgd_ref = pgd_offset_k(address);
187 struct page *page;
188
189 if (pgd_none(*pgd_ref))
190 continue;
191
192 spin_lock(&pgd_lock);
193 list_for_each_entry(page, &pgd_list, lru) {
194 pgd_t *pgd;
195 spinlock_t *pgt_lock;
196
197 pgd = (pgd_t *)page_address(page) + pgd_index(address);
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 (pgd_none(*pgd))
203 set_pgd(pgd, *pgd_ref);
204 else
205 BUG_ON(pgd_page_vaddr(*pgd)
206 != pgd_page_vaddr(*pgd_ref));
207
208 spin_unlock(pgt_lock);
209 }
210 spin_unlock(&pgd_lock);
211 }
212 }
213
214 /*
215 * NOTE: This function is marked __ref because it calls __init function
216 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
217 */
218 static __ref void *spp_getpage(void)
219 {
220 void *ptr;
221
222 if (after_bootmem)
223 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
224 else
225 ptr = alloc_bootmem_pages(PAGE_SIZE);
226
227 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
228 panic("set_pte_phys: cannot allocate page data %s\n",
229 after_bootmem ? "after bootmem" : "");
230 }
231
232 pr_debug("spp_getpage %p\n", ptr);
233
234 return ptr;
235 }
236
237 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
238 {
239 if (pgd_none(*pgd)) {
240 pud_t *pud = (pud_t *)spp_getpage();
241 pgd_populate(&init_mm, pgd, pud);
242 if (pud != pud_offset(pgd, 0))
243 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
244 pud, pud_offset(pgd, 0));
245 }
246 return pud_offset(pgd, vaddr);
247 }
248
249 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
250 {
251 if (pud_none(*pud)) {
252 pmd_t *pmd = (pmd_t *) spp_getpage();
253 pud_populate(&init_mm, pud, pmd);
254 if (pmd != pmd_offset(pud, 0))
255 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
256 pmd, pmd_offset(pud, 0));
257 }
258 return pmd_offset(pud, vaddr);
259 }
260
261 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
262 {
263 if (pmd_none(*pmd)) {
264 pte_t *pte = (pte_t *) spp_getpage();
265 pmd_populate_kernel(&init_mm, pmd, pte);
266 if (pte != pte_offset_kernel(pmd, 0))
267 printk(KERN_ERR "PAGETABLE BUG #02!\n");
268 }
269 return pte_offset_kernel(pmd, vaddr);
270 }
271
272 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
273 {
274 pud_t *pud;
275 pmd_t *pmd;
276 pte_t *pte;
277
278 pud = pud_page + pud_index(vaddr);
279 pmd = fill_pmd(pud, vaddr);
280 pte = fill_pte(pmd, vaddr);
281
282 set_pte(pte, new_pte);
283
284 /*
285 * It's enough to flush this one mapping.
286 * (PGE mappings get flushed as well)
287 */
288 __flush_tlb_one(vaddr);
289 }
290
291 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
292 {
293 pgd_t *pgd;
294 pud_t *pud_page;
295
296 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
297
298 pgd = pgd_offset_k(vaddr);
299 if (pgd_none(*pgd)) {
300 printk(KERN_ERR
301 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
302 return;
303 }
304 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
305 set_pte_vaddr_pud(pud_page, vaddr, pteval);
306 }
307
308 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
309 {
310 pgd_t *pgd;
311 pud_t *pud;
312
313 pgd = pgd_offset_k(vaddr);
314 pud = fill_pud(pgd, vaddr);
315 return fill_pmd(pud, vaddr);
316 }
317
318 pte_t * __init populate_extra_pte(unsigned long vaddr)
319 {
320 pmd_t *pmd;
321
322 pmd = populate_extra_pmd(vaddr);
323 return fill_pte(pmd, vaddr);
324 }
325
326 /*
327 * Create large page table mappings for a range of physical addresses.
328 */
329 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
330 pgprot_t prot)
331 {
332 pgd_t *pgd;
333 pud_t *pud;
334 pmd_t *pmd;
335
336 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
337 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
338 pgd = pgd_offset_k((unsigned long)__va(phys));
339 if (pgd_none(*pgd)) {
340 pud = (pud_t *) spp_getpage();
341 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
342 _PAGE_USER));
343 }
344 pud = pud_offset(pgd, (unsigned long)__va(phys));
345 if (pud_none(*pud)) {
346 pmd = (pmd_t *) spp_getpage();
347 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
348 _PAGE_USER));
349 }
350 pmd = pmd_offset(pud, phys);
351 BUG_ON(!pmd_none(*pmd));
352 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
353 }
354 }
355
356 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
357 {
358 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
359 }
360
361 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
362 {
363 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
364 }
365
366 /*
367 * The head.S code sets up the kernel high mapping:
368 *
369 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
370 *
371 * phys_base holds the negative offset to the kernel, which is added
372 * to the compile time generated pmds. This results in invalid pmds up
373 * to the point where we hit the physaddr 0 mapping.
374 *
375 * We limit the mappings to the region from _text to _brk_end. _brk_end
376 * is rounded up to the 2MB boundary. This catches the invalid pmds as
377 * well, as they are located before _text:
378 */
379 void __init cleanup_highmap(void)
380 {
381 unsigned long vaddr = __START_KERNEL_map;
382 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
383 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
384 pmd_t *pmd = level2_kernel_pgt;
385
386 /*
387 * Native path, max_pfn_mapped is not set yet.
388 * Xen has valid max_pfn_mapped set in
389 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
390 */
391 if (max_pfn_mapped)
392 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
393
394 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
395 if (pmd_none(*pmd))
396 continue;
397 if (vaddr < (unsigned long) _text || vaddr > end)
398 set_pmd(pmd, __pmd(0));
399 }
400 }
401
402 static unsigned long __meminit
403 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
404 pgprot_t prot)
405 {
406 unsigned long pages = 0, next;
407 unsigned long last_map_addr = end;
408 int i;
409
410 pte_t *pte = pte_page + pte_index(addr);
411
412 for (i = pte_index(addr); i < PTRS_PER_PTE; i++, addr = next, pte++) {
413 next = (addr & PAGE_MASK) + PAGE_SIZE;
414 if (addr >= end) {
415 if (!after_bootmem &&
416 !e820_any_mapped(addr & PAGE_MASK, next, E820_RAM) &&
417 !e820_any_mapped(addr & PAGE_MASK, next, E820_RESERVED_KERN))
418 set_pte(pte, __pte(0));
419 continue;
420 }
421
422 /*
423 * We will re-use the existing mapping.
424 * Xen for example has some special requirements, like mapping
425 * pagetable pages as RO. So assume someone who pre-setup
426 * these mappings are more intelligent.
427 */
428 if (pte_val(*pte)) {
429 if (!after_bootmem)
430 pages++;
431 continue;
432 }
433
434 if (0)
435 printk(" pte=%p addr=%lx pte=%016lx\n",
436 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
437 pages++;
438 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
439 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
440 }
441
442 update_page_count(PG_LEVEL_4K, pages);
443
444 return last_map_addr;
445 }
446
447 static unsigned long __meminit
448 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
449 unsigned long page_size_mask, pgprot_t prot)
450 {
451 unsigned long pages = 0, next;
452 unsigned long last_map_addr = end;
453
454 int i = pmd_index(address);
455
456 for (; i < PTRS_PER_PMD; i++, address = next) {
457 pmd_t *pmd = pmd_page + pmd_index(address);
458 pte_t *pte;
459 pgprot_t new_prot = prot;
460
461 next = (address & PMD_MASK) + PMD_SIZE;
462 if (address >= end) {
463 if (!after_bootmem &&
464 !e820_any_mapped(address & PMD_MASK, next, E820_RAM) &&
465 !e820_any_mapped(address & PMD_MASK, next, E820_RESERVED_KERN))
466 set_pmd(pmd, __pmd(0));
467 continue;
468 }
469
470 if (pmd_val(*pmd)) {
471 if (!pmd_large(*pmd)) {
472 spin_lock(&init_mm.page_table_lock);
473 pte = (pte_t *)pmd_page_vaddr(*pmd);
474 last_map_addr = phys_pte_init(pte, address,
475 end, prot);
476 spin_unlock(&init_mm.page_table_lock);
477 continue;
478 }
479 /*
480 * If we are ok with PG_LEVEL_2M mapping, then we will
481 * use the existing mapping,
482 *
483 * Otherwise, we will split the large page mapping but
484 * use the same existing protection bits except for
485 * large page, so that we don't violate Intel's TLB
486 * Application note (317080) which says, while changing
487 * the page sizes, new and old translations should
488 * not differ with respect to page frame and
489 * attributes.
490 */
491 if (page_size_mask & (1 << PG_LEVEL_2M)) {
492 if (!after_bootmem)
493 pages++;
494 last_map_addr = next;
495 continue;
496 }
497 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
498 }
499
500 if (page_size_mask & (1<<PG_LEVEL_2M)) {
501 pages++;
502 spin_lock(&init_mm.page_table_lock);
503 set_pte((pte_t *)pmd,
504 pfn_pte((address & PMD_MASK) >> PAGE_SHIFT,
505 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
506 spin_unlock(&init_mm.page_table_lock);
507 last_map_addr = next;
508 continue;
509 }
510
511 pte = alloc_low_page();
512 last_map_addr = phys_pte_init(pte, address, end, new_prot);
513
514 spin_lock(&init_mm.page_table_lock);
515 pmd_populate_kernel(&init_mm, pmd, pte);
516 spin_unlock(&init_mm.page_table_lock);
517 }
518 update_page_count(PG_LEVEL_2M, pages);
519 return last_map_addr;
520 }
521
522 static unsigned long __meminit
523 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
524 unsigned long page_size_mask)
525 {
526 unsigned long pages = 0, next;
527 unsigned long last_map_addr = end;
528 int i = pud_index(addr);
529
530 for (; i < PTRS_PER_PUD; i++, addr = next) {
531 pud_t *pud = pud_page + pud_index(addr);
532 pmd_t *pmd;
533 pgprot_t prot = PAGE_KERNEL;
534
535 next = (addr & PUD_MASK) + PUD_SIZE;
536 if (addr >= end) {
537 if (!after_bootmem &&
538 !e820_any_mapped(addr & PUD_MASK, next, E820_RAM) &&
539 !e820_any_mapped(addr & PUD_MASK, next, E820_RESERVED_KERN))
540 set_pud(pud, __pud(0));
541 continue;
542 }
543
544 if (pud_val(*pud)) {
545 if (!pud_large(*pud)) {
546 pmd = pmd_offset(pud, 0);
547 last_map_addr = phys_pmd_init(pmd, addr, end,
548 page_size_mask, prot);
549 __flush_tlb_all();
550 continue;
551 }
552 /*
553 * If we are ok with PG_LEVEL_1G mapping, then we will
554 * use the existing mapping.
555 *
556 * Otherwise, we will split the gbpage mapping but use
557 * the same existing protection bits except for large
558 * page, so that we don't violate Intel's TLB
559 * Application note (317080) which says, while changing
560 * the page sizes, new and old translations should
561 * not differ with respect to page frame and
562 * attributes.
563 */
564 if (page_size_mask & (1 << PG_LEVEL_1G)) {
565 if (!after_bootmem)
566 pages++;
567 last_map_addr = next;
568 continue;
569 }
570 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
571 }
572
573 if (page_size_mask & (1<<PG_LEVEL_1G)) {
574 pages++;
575 spin_lock(&init_mm.page_table_lock);
576 set_pte((pte_t *)pud,
577 pfn_pte((addr & PUD_MASK) >> PAGE_SHIFT,
578 PAGE_KERNEL_LARGE));
579 spin_unlock(&init_mm.page_table_lock);
580 last_map_addr = next;
581 continue;
582 }
583
584 pmd = alloc_low_page();
585 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
586 prot);
587
588 spin_lock(&init_mm.page_table_lock);
589 pud_populate(&init_mm, pud, pmd);
590 spin_unlock(&init_mm.page_table_lock);
591 }
592 __flush_tlb_all();
593
594 update_page_count(PG_LEVEL_1G, pages);
595
596 return last_map_addr;
597 }
598
599 unsigned long __meminit
600 kernel_physical_mapping_init(unsigned long start,
601 unsigned long end,
602 unsigned long page_size_mask)
603 {
604 bool pgd_changed = false;
605 unsigned long next, last_map_addr = end;
606 unsigned long addr;
607
608 start = (unsigned long)__va(start);
609 end = (unsigned long)__va(end);
610 addr = start;
611
612 for (; start < end; start = next) {
613 pgd_t *pgd = pgd_offset_k(start);
614 pud_t *pud;
615
616 next = (start & PGDIR_MASK) + PGDIR_SIZE;
617
618 if (pgd_val(*pgd)) {
619 pud = (pud_t *)pgd_page_vaddr(*pgd);
620 last_map_addr = phys_pud_init(pud, __pa(start),
621 __pa(end), page_size_mask);
622 continue;
623 }
624
625 pud = alloc_low_page();
626 last_map_addr = phys_pud_init(pud, __pa(start), __pa(end),
627 page_size_mask);
628
629 spin_lock(&init_mm.page_table_lock);
630 pgd_populate(&init_mm, pgd, pud);
631 spin_unlock(&init_mm.page_table_lock);
632 pgd_changed = true;
633 }
634
635 if (pgd_changed)
636 sync_global_pgds(addr, end - 1);
637
638 __flush_tlb_all();
639
640 return last_map_addr;
641 }
642
643 #ifndef CONFIG_NUMA
644 void __init initmem_init(void)
645 {
646 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
647 }
648 #endif
649
650 void __init paging_init(void)
651 {
652 sparse_memory_present_with_active_regions(MAX_NUMNODES);
653 sparse_init();
654
655 /*
656 * clear the default setting with node 0
657 * note: don't use nodes_clear here, that is really clearing when
658 * numa support is not compiled in, and later node_set_state
659 * will not set it back.
660 */
661 node_clear_state(0, N_MEMORY);
662 if (N_MEMORY != N_NORMAL_MEMORY)
663 node_clear_state(0, N_NORMAL_MEMORY);
664
665 zone_sizes_init();
666 }
667
668 /*
669 * Memory hotplug specific functions
670 */
671 #ifdef CONFIG_MEMORY_HOTPLUG
672 /*
673 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
674 * updating.
675 */
676 static void update_end_of_memory_vars(u64 start, u64 size)
677 {
678 unsigned long end_pfn = PFN_UP(start + size);
679
680 if (end_pfn > max_pfn) {
681 max_pfn = end_pfn;
682 max_low_pfn = end_pfn;
683 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
684 }
685 }
686
687 /*
688 * Memory is added always to NORMAL zone. This means you will never get
689 * additional DMA/DMA32 memory.
690 */
691 int arch_add_memory(int nid, u64 start, u64 size)
692 {
693 struct pglist_data *pgdat = NODE_DATA(nid);
694 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
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 (IS_ALIGNED(addr, PAGE_SIZE) &&
818 IS_ALIGNED(next, PAGE_SIZE)) {
819 /*
820 * Do not free direct mapping pages since they were
821 * freed when offlining, or simplely not in use.
822 */
823 if (!direct)
824 free_pagetable(pte_page(*pte), 0);
825
826 spin_lock(&init_mm.page_table_lock);
827 pte_clear(&init_mm, addr, pte);
828 spin_unlock(&init_mm.page_table_lock);
829
830 /* For non-direct mapping, pages means nothing. */
831 pages++;
832 } else {
833 /*
834 * If we are here, we are freeing vmemmap pages since
835 * direct mapped memory ranges to be freed are aligned.
836 *
837 * If we are not removing the whole page, it means
838 * other page structs in this page are being used and
839 * we canot remove them. So fill the unused page_structs
840 * with 0xFD, and remove the page when it is wholly
841 * filled with 0xFD.
842 */
843 memset((void *)addr, PAGE_INUSE, next - addr);
844
845 page_addr = page_address(pte_page(*pte));
846 if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
847 free_pagetable(pte_page(*pte), 0);
848
849 spin_lock(&init_mm.page_table_lock);
850 pte_clear(&init_mm, addr, pte);
851 spin_unlock(&init_mm.page_table_lock);
852 }
853 }
854 }
855
856 /* Call free_pte_table() in remove_pmd_table(). */
857 flush_tlb_all();
858 if (direct)
859 update_page_count(PG_LEVEL_4K, -pages);
860 }
861
862 static void __meminit
863 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
864 bool direct)
865 {
866 unsigned long next, pages = 0;
867 pte_t *pte_base;
868 pmd_t *pmd;
869 void *page_addr;
870
871 pmd = pmd_start + pmd_index(addr);
872 for (; addr < end; addr = next, pmd++) {
873 next = pmd_addr_end(addr, end);
874
875 if (!pmd_present(*pmd))
876 continue;
877
878 if (pmd_large(*pmd)) {
879 if (IS_ALIGNED(addr, PMD_SIZE) &&
880 IS_ALIGNED(next, PMD_SIZE)) {
881 if (!direct)
882 free_pagetable(pmd_page(*pmd),
883 get_order(PMD_SIZE));
884
885 spin_lock(&init_mm.page_table_lock);
886 pmd_clear(pmd);
887 spin_unlock(&init_mm.page_table_lock);
888 pages++;
889 } else {
890 /* If here, we are freeing vmemmap pages. */
891 memset((void *)addr, PAGE_INUSE, next - addr);
892
893 page_addr = page_address(pmd_page(*pmd));
894 if (!memchr_inv(page_addr, PAGE_INUSE,
895 PMD_SIZE)) {
896 free_pagetable(pmd_page(*pmd),
897 get_order(PMD_SIZE));
898
899 spin_lock(&init_mm.page_table_lock);
900 pmd_clear(pmd);
901 spin_unlock(&init_mm.page_table_lock);
902 }
903 }
904
905 continue;
906 }
907
908 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
909 remove_pte_table(pte_base, addr, next, direct);
910 free_pte_table(pte_base, pmd);
911 }
912
913 /* Call free_pmd_table() in remove_pud_table(). */
914 if (direct)
915 update_page_count(PG_LEVEL_2M, -pages);
916 }
917
918 static void __meminit
919 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
920 bool direct)
921 {
922 unsigned long next, pages = 0;
923 pmd_t *pmd_base;
924 pud_t *pud;
925 void *page_addr;
926
927 pud = pud_start + pud_index(addr);
928 for (; addr < end; addr = next, pud++) {
929 next = pud_addr_end(addr, end);
930
931 if (!pud_present(*pud))
932 continue;
933
934 if (pud_large(*pud)) {
935 if (IS_ALIGNED(addr, PUD_SIZE) &&
936 IS_ALIGNED(next, PUD_SIZE)) {
937 if (!direct)
938 free_pagetable(pud_page(*pud),
939 get_order(PUD_SIZE));
940
941 spin_lock(&init_mm.page_table_lock);
942 pud_clear(pud);
943 spin_unlock(&init_mm.page_table_lock);
944 pages++;
945 } else {
946 /* If here, we are freeing vmemmap pages. */
947 memset((void *)addr, PAGE_INUSE, next - addr);
948
949 page_addr = page_address(pud_page(*pud));
950 if (!memchr_inv(page_addr, PAGE_INUSE,
951 PUD_SIZE)) {
952 free_pagetable(pud_page(*pud),
953 get_order(PUD_SIZE));
954
955 spin_lock(&init_mm.page_table_lock);
956 pud_clear(pud);
957 spin_unlock(&init_mm.page_table_lock);
958 }
959 }
960
961 continue;
962 }
963
964 pmd_base = (pmd_t *)pud_page_vaddr(*pud);
965 remove_pmd_table(pmd_base, addr, next, direct);
966 free_pmd_table(pmd_base, pud);
967 }
968
969 if (direct)
970 update_page_count(PG_LEVEL_1G, -pages);
971 }
972
973 /* start and end are both virtual address. */
974 static void __meminit
975 remove_pagetable(unsigned long start, unsigned long end, bool direct)
976 {
977 unsigned long next;
978 pgd_t *pgd;
979 pud_t *pud;
980 bool pgd_changed = false;
981
982 for (; start < end; start = next) {
983 next = pgd_addr_end(start, end);
984
985 pgd = pgd_offset_k(start);
986 if (!pgd_present(*pgd))
987 continue;
988
989 pud = (pud_t *)pgd_page_vaddr(*pgd);
990 remove_pud_table(pud, start, 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);
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 = PFN_ALIGN(&_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 set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT);
1126
1127 rodata_test();
1128
1129 #ifdef CONFIG_CPA_DEBUG
1130 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1131 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1132
1133 printk(KERN_INFO "Testing CPA: again\n");
1134 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1135 #endif
1136
1137 free_init_pages("unused kernel",
1138 (unsigned long) __va(__pa_symbol(text_end)),
1139 (unsigned long) __va(__pa_symbol(rodata_start)));
1140 free_init_pages("unused kernel",
1141 (unsigned long) __va(__pa_symbol(rodata_end)),
1142 (unsigned long) __va(__pa_symbol(_sdata)));
1143 }
1144
1145 #endif
1146
1147 int kern_addr_valid(unsigned long addr)
1148 {
1149 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1150 pgd_t *pgd;
1151 pud_t *pud;
1152 pmd_t *pmd;
1153 pte_t *pte;
1154
1155 if (above != 0 && above != -1UL)
1156 return 0;
1157
1158 pgd = pgd_offset_k(addr);
1159 if (pgd_none(*pgd))
1160 return 0;
1161
1162 pud = pud_offset(pgd, addr);
1163 if (pud_none(*pud))
1164 return 0;
1165
1166 if (pud_large(*pud))
1167 return pfn_valid(pud_pfn(*pud));
1168
1169 pmd = pmd_offset(pud, addr);
1170 if (pmd_none(*pmd))
1171 return 0;
1172
1173 if (pmd_large(*pmd))
1174 return pfn_valid(pmd_pfn(*pmd));
1175
1176 pte = pte_offset_kernel(pmd, addr);
1177 if (pte_none(*pte))
1178 return 0;
1179
1180 return pfn_valid(pte_pfn(*pte));
1181 }
1182
1183 /*
1184 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
1185 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1186 * not need special handling anymore:
1187 */
1188 static struct vm_area_struct gate_vma = {
1189 .vm_start = VSYSCALL_ADDR,
1190 .vm_end = VSYSCALL_ADDR + PAGE_SIZE,
1191 .vm_page_prot = PAGE_READONLY_EXEC,
1192 .vm_flags = VM_READ | VM_EXEC
1193 };
1194
1195 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
1196 {
1197 #ifdef CONFIG_IA32_EMULATION
1198 if (!mm || mm->context.ia32_compat)
1199 return NULL;
1200 #endif
1201 return &gate_vma;
1202 }
1203
1204 int in_gate_area(struct mm_struct *mm, unsigned long addr)
1205 {
1206 struct vm_area_struct *vma = get_gate_vma(mm);
1207
1208 if (!vma)
1209 return 0;
1210
1211 return (addr >= vma->vm_start) && (addr < vma->vm_end);
1212 }
1213
1214 /*
1215 * Use this when you have no reliable mm, typically from interrupt
1216 * context. It is less reliable than using a task's mm and may give
1217 * false positives.
1218 */
1219 int in_gate_area_no_mm(unsigned long addr)
1220 {
1221 return (addr & PAGE_MASK) == VSYSCALL_ADDR;
1222 }
1223
1224 const char *arch_vma_name(struct vm_area_struct *vma)
1225 {
1226 if (vma->vm_mm && vma->vm_start ==
1227 (long __force)vma->vm_mm->context.vdso)
1228 return "[vdso]";
1229 if (vma == &gate_vma)
1230 return "[vsyscall]";
1231 return NULL;
1232 }
1233
1234 #ifdef CONFIG_X86_UV
1235 unsigned long memory_block_size_bytes(void)
1236 {
1237 if (is_uv_system()) {
1238 printk(KERN_INFO "UV: memory block size 2GB\n");
1239 return 2UL * 1024 * 1024 * 1024;
1240 }
1241 return MIN_MEMORY_BLOCK_SIZE;
1242 }
1243 #endif
1244
1245 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1246 /*
1247 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1248 */
1249 static long __meminitdata addr_start, addr_end;
1250 static void __meminitdata *p_start, *p_end;
1251 static int __meminitdata node_start;
1252
1253 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1254 unsigned long end, int node)
1255 {
1256 unsigned long addr;
1257 unsigned long next;
1258 pgd_t *pgd;
1259 pud_t *pud;
1260 pmd_t *pmd;
1261
1262 for (addr = start; addr < end; addr = next) {
1263 next = pmd_addr_end(addr, end);
1264
1265 pgd = vmemmap_pgd_populate(addr, node);
1266 if (!pgd)
1267 return -ENOMEM;
1268
1269 pud = vmemmap_pud_populate(pgd, addr, node);
1270 if (!pud)
1271 return -ENOMEM;
1272
1273 pmd = pmd_offset(pud, addr);
1274 if (pmd_none(*pmd)) {
1275 void *p;
1276
1277 p = vmemmap_alloc_block_buf(PMD_SIZE, node);
1278 if (p) {
1279 pte_t entry;
1280
1281 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1282 PAGE_KERNEL_LARGE);
1283 set_pmd(pmd, __pmd(pte_val(entry)));
1284
1285 /* check to see if we have contiguous blocks */
1286 if (p_end != p || node_start != node) {
1287 if (p_start)
1288 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1289 addr_start, addr_end-1, p_start, p_end-1, node_start);
1290 addr_start = addr;
1291 node_start = node;
1292 p_start = p;
1293 }
1294
1295 addr_end = addr + PMD_SIZE;
1296 p_end = p + PMD_SIZE;
1297 continue;
1298 }
1299 } else if (pmd_large(*pmd)) {
1300 vmemmap_verify((pte_t *)pmd, node, addr, next);
1301 continue;
1302 }
1303 pr_warn_once("vmemmap: falling back to regular page backing\n");
1304 if (vmemmap_populate_basepages(addr, next, node))
1305 return -ENOMEM;
1306 }
1307 return 0;
1308 }
1309
1310 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
1311 {
1312 int err;
1313
1314 if (cpu_has_pse)
1315 err = vmemmap_populate_hugepages(start, end, node);
1316 else
1317 err = vmemmap_populate_basepages(start, end, node);
1318 if (!err)
1319 sync_global_pgds(start, end - 1);
1320 return err;
1321 }
1322
1323 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1324 void register_page_bootmem_memmap(unsigned long section_nr,
1325 struct page *start_page, unsigned long size)
1326 {
1327 unsigned long addr = (unsigned long)start_page;
1328 unsigned long end = (unsigned long)(start_page + size);
1329 unsigned long next;
1330 pgd_t *pgd;
1331 pud_t *pud;
1332 pmd_t *pmd;
1333 unsigned int nr_pages;
1334 struct page *page;
1335
1336 for (; addr < end; addr = next) {
1337 pte_t *pte = NULL;
1338
1339 pgd = pgd_offset_k(addr);
1340 if (pgd_none(*pgd)) {
1341 next = (addr + PAGE_SIZE) & PAGE_MASK;
1342 continue;
1343 }
1344 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1345
1346 pud = pud_offset(pgd, addr);
1347 if (pud_none(*pud)) {
1348 next = (addr + PAGE_SIZE) & PAGE_MASK;
1349 continue;
1350 }
1351 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1352
1353 if (!cpu_has_pse) {
1354 next = (addr + PAGE_SIZE) & PAGE_MASK;
1355 pmd = pmd_offset(pud, addr);
1356 if (pmd_none(*pmd))
1357 continue;
1358 get_page_bootmem(section_nr, pmd_page(*pmd),
1359 MIX_SECTION_INFO);
1360
1361 pte = pte_offset_kernel(pmd, addr);
1362 if (pte_none(*pte))
1363 continue;
1364 get_page_bootmem(section_nr, pte_page(*pte),
1365 SECTION_INFO);
1366 } else {
1367 next = pmd_addr_end(addr, end);
1368
1369 pmd = pmd_offset(pud, addr);
1370 if (pmd_none(*pmd))
1371 continue;
1372
1373 nr_pages = 1 << (get_order(PMD_SIZE));
1374 page = pmd_page(*pmd);
1375 while (nr_pages--)
1376 get_page_bootmem(section_nr, page++,
1377 SECTION_INFO);
1378 }
1379 }
1380 }
1381 #endif
1382
1383 void __meminit vmemmap_populate_print_last(void)
1384 {
1385 if (p_start) {
1386 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1387 addr_start, addr_end-1, p_start, p_end-1, node_start);
1388 p_start = NULL;
1389 p_end = NULL;
1390 node_start = 0;
1391 }
1392 }
1393 #endif
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