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x86, memory hotplug: remove wrong -1 in calling init_memory_mapping()
[linux-2.6/kvm.git] / arch / x86 / mm / init_64.c
blobf79a02f64d108dde4de4a35055240f64fae2371b
1 /*
2 * linux/arch/x86_64/mm/init.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 * Copyright (C) 2000 Pavel Machek <pavel@suse.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/proc_fs.h>
25 #include <linux/pci.h>
26 #include <linux/pfn.h>
27 #include <linux/poison.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/module.h>
30 #include <linux/memory_hotplug.h>
31 #include <linux/nmi.h>
32
33 #include <asm/processor.h>
34 #include <asm/bios_ebda.h>
35 #include <asm/system.h>
36 #include <asm/uaccess.h>
37 #include <asm/pgtable.h>
38 #include <asm/pgalloc.h>
39 #include <asm/dma.h>
40 #include <asm/fixmap.h>
41 #include <asm/e820.h>
42 #include <asm/apic.h>
43 #include <asm/tlb.h>
44 #include <asm/mmu_context.h>
45 #include <asm/proto.h>
46 #include <asm/smp.h>
47 #include <asm/sections.h>
48 #include <asm/kdebug.h>
49 #include <asm/numa.h>
50 #include <asm/cacheflush.h>
51
52 /*
53 * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
54 * The direct mapping extends to max_pfn_mapped, so that we can directly access
55 * apertures, ACPI and other tables without having to play with fixmaps.
56 */
57 unsigned long max_low_pfn_mapped;
58 unsigned long max_pfn_mapped;
59
60 static unsigned long dma_reserve __initdata;
61
62 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
63
64 int direct_gbpages
65 #ifdef CONFIG_DIRECT_GBPAGES
66 = 1
67 #endif
68 ;
69
70 static int __init parse_direct_gbpages_off(char *arg)
71 {
72 direct_gbpages = 0;
73 return 0;
74 }
75 early_param("nogbpages", parse_direct_gbpages_off);
76
77 static int __init parse_direct_gbpages_on(char *arg)
78 {
79 direct_gbpages = 1;
80 return 0;
81 }
82 early_param("gbpages", parse_direct_gbpages_on);
83
84 /*
85 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
86 * physical space so we can cache the place of the first one and move
87 * around without checking the pgd every time.
88 */
89
90 int after_bootmem;
91
92 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
93 EXPORT_SYMBOL_GPL(__supported_pte_mask);
94
95 static int do_not_nx __cpuinitdata;
96
97 /*
98 * noexec=on|off
99 * Control non-executable mappings for 64-bit processes.
100 *
101 * on Enable (default)
102 * off Disable
103 */
104 static int __init nonx_setup(char *str)
105 {
106 if (!str)
107 return -EINVAL;
108 if (!strncmp(str, "on", 2)) {
109 __supported_pte_mask |= _PAGE_NX;
110 do_not_nx = 0;
111 } else if (!strncmp(str, "off", 3)) {
112 do_not_nx = 1;
113 __supported_pte_mask &= ~_PAGE_NX;
114 }
115 return 0;
116 }
117 early_param("noexec", nonx_setup);
118
119 void __cpuinit check_efer(void)
120 {
121 unsigned long efer;
122
123 rdmsrl(MSR_EFER, efer);
124 if (!(efer & EFER_NX) || do_not_nx)
125 __supported_pte_mask &= ~_PAGE_NX;
126 }
127
128 int force_personality32;
129
130 /*
131 * noexec32=on|off
132 * Control non executable heap for 32bit processes.
133 * To control the stack too use noexec=off
134 *
135 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
136 * off PROT_READ implies PROT_EXEC
137 */
138 static int __init nonx32_setup(char *str)
139 {
140 if (!strcmp(str, "on"))
141 force_personality32 &= ~READ_IMPLIES_EXEC;
142 else if (!strcmp(str, "off"))
143 force_personality32 |= READ_IMPLIES_EXEC;
144 return 1;
145 }
146 __setup("noexec32=", nonx32_setup);
147
148 /*
149 * NOTE: This function is marked __ref because it calls __init function
150 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
151 */
152 static __ref void *spp_getpage(void)
153 {
154 void *ptr;
155
156 if (after_bootmem)
157 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
158 else
159 ptr = alloc_bootmem_pages(PAGE_SIZE);
160
161 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
162 panic("set_pte_phys: cannot allocate page data %s\n",
163 after_bootmem ? "after bootmem" : "");
164 }
165
166 pr_debug("spp_getpage %p\n", ptr);
167
168 return ptr;
169 }
170
171 void
172 set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
173 {
174 pud_t *pud;
175 pmd_t *pmd;
176 pte_t *pte;
177
178 pud = pud_page + pud_index(vaddr);
179 if (pud_none(*pud)) {
180 pmd = (pmd_t *) spp_getpage();
181 pud_populate(&init_mm, pud, pmd);
182 if (pmd != pmd_offset(pud, 0)) {
183 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
184 pmd, pmd_offset(pud, 0));
185 return;
186 }
187 }
188 pmd = pmd_offset(pud, vaddr);
189 if (pmd_none(*pmd)) {
190 pte = (pte_t *) spp_getpage();
191 pmd_populate_kernel(&init_mm, pmd, pte);
192 if (pte != pte_offset_kernel(pmd, 0)) {
193 printk(KERN_ERR "PAGETABLE BUG #02!\n");
194 return;
195 }
196 }
197
198 pte = pte_offset_kernel(pmd, vaddr);
199 set_pte(pte, new_pte);
200
201 /*
202 * It's enough to flush this one mapping.
203 * (PGE mappings get flushed as well)
204 */
205 __flush_tlb_one(vaddr);
206 }
207
208 void
209 set_pte_vaddr(unsigned long vaddr, pte_t pteval)
210 {
211 pgd_t *pgd;
212 pud_t *pud_page;
213
214 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
215
216 pgd = pgd_offset_k(vaddr);
217 if (pgd_none(*pgd)) {
218 printk(KERN_ERR
219 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
220 return;
221 }
222 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
223 set_pte_vaddr_pud(pud_page, vaddr, pteval);
224 }
225
226 /*
227 * Create large page table mappings for a range of physical addresses.
228 */
229 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
230 pgprot_t prot)
231 {
232 pgd_t *pgd;
233 pud_t *pud;
234 pmd_t *pmd;
235
236 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
237 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
238 pgd = pgd_offset_k((unsigned long)__va(phys));
239 if (pgd_none(*pgd)) {
240 pud = (pud_t *) spp_getpage();
241 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
242 _PAGE_USER));
243 }
244 pud = pud_offset(pgd, (unsigned long)__va(phys));
245 if (pud_none(*pud)) {
246 pmd = (pmd_t *) spp_getpage();
247 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
248 _PAGE_USER));
249 }
250 pmd = pmd_offset(pud, phys);
251 BUG_ON(!pmd_none(*pmd));
252 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
253 }
254 }
255
256 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
257 {
258 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
259 }
260
261 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
262 {
263 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
264 }
265
266 /*
267 * The head.S code sets up the kernel high mapping:
268 *
269 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
270 *
271 * phys_addr holds the negative offset to the kernel, which is added
272 * to the compile time generated pmds. This results in invalid pmds up
273 * to the point where we hit the physaddr 0 mapping.
274 *
275 * We limit the mappings to the region from _text to _end. _end is
276 * rounded up to the 2MB boundary. This catches the invalid pmds as
277 * well, as they are located before _text:
278 */
279 void __init cleanup_highmap(void)
280 {
281 unsigned long vaddr = __START_KERNEL_map;
282 unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
283 pmd_t *pmd = level2_kernel_pgt;
284 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
285
286 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
287 if (pmd_none(*pmd))
288 continue;
289 if (vaddr < (unsigned long) _text || vaddr > end)
290 set_pmd(pmd, __pmd(0));
291 }
292 }
293
294 static unsigned long __initdata table_start;
295 static unsigned long __meminitdata table_end;
296 static unsigned long __meminitdata table_top;
297
298 static __ref void *alloc_low_page(unsigned long *phys)
299 {
300 unsigned long pfn = table_end++;
301 void *adr;
302
303 if (after_bootmem) {
304 adr = (void *)get_zeroed_page(GFP_ATOMIC);
305 *phys = __pa(adr);
306
307 return adr;
308 }
309
310 if (pfn >= table_top)
311 panic("alloc_low_page: ran out of memory");
312
313 adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
314 memset(adr, 0, PAGE_SIZE);
315 *phys = pfn * PAGE_SIZE;
316 return adr;
317 }
318
319 static __ref void unmap_low_page(void *adr)
320 {
321 if (after_bootmem)
322 return;
323
324 early_iounmap(adr, PAGE_SIZE);
325 }
326
327 static unsigned long __meminit
328 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
329 pgprot_t prot)
330 {
331 unsigned pages = 0;
332 unsigned long last_map_addr = end;
333 int i;
334
335 pte_t *pte = pte_page + pte_index(addr);
336
337 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
338
339 if (addr >= end) {
340 if (!after_bootmem) {
341 for(; i < PTRS_PER_PTE; i++, pte++)
342 set_pte(pte, __pte(0));
343 }
344 break;
345 }
346
347 /*
348 * We will re-use the existing mapping.
349 * Xen for example has some special requirements, like mapping
350 * pagetable pages as RO. So assume someone who pre-setup
351 * these mappings are more intelligent.
352 */
353 if (pte_val(*pte)) {
354 pages++;
355 continue;
356 }
357
358 if (0)
359 printk(" pte=%p addr=%lx pte=%016lx\n",
360 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
361 pages++;
362 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
363 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
364 }
365
366 update_page_count(PG_LEVEL_4K, pages);
367
368 return last_map_addr;
369 }
370
371 static unsigned long __meminit
372 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end,
373 pgprot_t prot)
374 {
375 pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
376
377 return phys_pte_init(pte, address, end, prot);
378 }
379
380 static unsigned long __meminit
381 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
382 unsigned long page_size_mask, pgprot_t prot)
383 {
384 unsigned long pages = 0;
385 unsigned long last_map_addr = end;
386
387 int i = pmd_index(address);
388
389 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
390 unsigned long pte_phys;
391 pmd_t *pmd = pmd_page + pmd_index(address);
392 pte_t *pte;
393 pgprot_t new_prot = prot;
394
395 if (address >= end) {
396 if (!after_bootmem) {
397 for (; i < PTRS_PER_PMD; i++, pmd++)
398 set_pmd(pmd, __pmd(0));
399 }
400 break;
401 }
402
403 if (pmd_val(*pmd)) {
404 if (!pmd_large(*pmd)) {
405 spin_lock(&init_mm.page_table_lock);
406 last_map_addr = phys_pte_update(pmd, address,
407 end, prot);
408 spin_unlock(&init_mm.page_table_lock);
409 continue;
410 }
411 /*
412 * If we are ok with PG_LEVEL_2M mapping, then we will
413 * use the existing mapping,
414 *
415 * Otherwise, we will split the large page mapping but
416 * use the same existing protection bits except for
417 * large page, so that we don't violate Intel's TLB
418 * Application note (317080) which says, while changing
419 * the page sizes, new and old translations should
420 * not differ with respect to page frame and
421 * attributes.
422 */
423 if (page_size_mask & (1 << PG_LEVEL_2M)) {
424 pages++;
425 continue;
426 }
427 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
428 }
429
430 if (page_size_mask & (1<<PG_LEVEL_2M)) {
431 pages++;
432 spin_lock(&init_mm.page_table_lock);
433 set_pte((pte_t *)pmd,
434 pfn_pte(address >> PAGE_SHIFT,
435 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
436 spin_unlock(&init_mm.page_table_lock);
437 last_map_addr = (address & PMD_MASK) + PMD_SIZE;
438 continue;
439 }
440
441 pte = alloc_low_page(&pte_phys);
442 last_map_addr = phys_pte_init(pte, address, end, new_prot);
443 unmap_low_page(pte);
444
445 spin_lock(&init_mm.page_table_lock);
446 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
447 spin_unlock(&init_mm.page_table_lock);
448 }
449 update_page_count(PG_LEVEL_2M, pages);
450 return last_map_addr;
451 }
452
453 static unsigned long __meminit
454 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
455 unsigned long page_size_mask, pgprot_t prot)
456 {
457 pmd_t *pmd = pmd_offset(pud, 0);
458 unsigned long last_map_addr;
459
460 last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot);
461 __flush_tlb_all();
462 return last_map_addr;
463 }
464
465 static unsigned long __meminit
466 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
467 unsigned long page_size_mask)
468 {
469 unsigned long pages = 0;
470 unsigned long last_map_addr = end;
471 int i = pud_index(addr);
472
473 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
474 unsigned long pmd_phys;
475 pud_t *pud = pud_page + pud_index(addr);
476 pmd_t *pmd;
477 pgprot_t prot = PAGE_KERNEL;
478
479 if (addr >= end)
480 break;
481
482 if (!after_bootmem &&
483 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
484 set_pud(pud, __pud(0));
485 continue;
486 }
487
488 if (pud_val(*pud)) {
489 if (!pud_large(*pud)) {
490 last_map_addr = phys_pmd_update(pud, addr, end,
491 page_size_mask, prot);
492 continue;
493 }
494 /*
495 * If we are ok with PG_LEVEL_1G mapping, then we will
496 * use the existing mapping.
497 *
498 * Otherwise, we will split the gbpage mapping but use
499 * the same existing protection bits except for large
500 * page, so that we don't violate Intel's TLB
501 * Application note (317080) which says, while changing
502 * the page sizes, new and old translations should
503 * not differ with respect to page frame and
504 * attributes.
505 */
506 if (page_size_mask & (1 << PG_LEVEL_1G)) {
507 pages++;
508 continue;
509 }
510 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
511 }
512
513 if (page_size_mask & (1<<PG_LEVEL_1G)) {
514 pages++;
515 spin_lock(&init_mm.page_table_lock);
516 set_pte((pte_t *)pud,
517 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
518 spin_unlock(&init_mm.page_table_lock);
519 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
520 continue;
521 }
522
523 pmd = alloc_low_page(&pmd_phys);
524 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
525 prot);
526 unmap_low_page(pmd);
527
528 spin_lock(&init_mm.page_table_lock);
529 pud_populate(&init_mm, pud, __va(pmd_phys));
530 spin_unlock(&init_mm.page_table_lock);
531 }
532 __flush_tlb_all();
533
534 update_page_count(PG_LEVEL_1G, pages);
535
536 return last_map_addr;
537 }
538
539 static unsigned long __meminit
540 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
541 unsigned long page_size_mask)
542 {
543 pud_t *pud;
544
545 pud = (pud_t *)pgd_page_vaddr(*pgd);
546
547 return phys_pud_init(pud, addr, end, page_size_mask);
548 }
549
550 static void __init find_early_table_space(unsigned long end, int use_pse,
551 int use_gbpages)
552 {
553 unsigned long puds, pmds, ptes, tables, start;
554
555 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
556 tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
557 if (use_gbpages) {
558 unsigned long extra;
559 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
560 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
561 } else
562 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
563 tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
564
565 if (use_pse) {
566 unsigned long extra;
567 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
568 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
569 } else
570 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
571 tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
572
573 /*
574 * RED-PEN putting page tables only on node 0 could
575 * cause a hotspot and fill up ZONE_DMA. The page tables
576 * need roughly 0.5KB per GB.
577 */
578 start = 0x8000;
579 table_start = find_e820_area(start, end, tables, PAGE_SIZE);
580 if (table_start == -1UL)
581 panic("Cannot find space for the kernel page tables");
582
583 table_start >>= PAGE_SHIFT;
584 table_end = table_start;
585 table_top = table_start + (tables >> PAGE_SHIFT);
586
587 printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
588 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
589 }
590
591 static void __init init_gbpages(void)
592 {
593 if (direct_gbpages && cpu_has_gbpages)
594 printk(KERN_INFO "Using GB pages for direct mapping\n");
595 else
596 direct_gbpages = 0;
597 }
598
599 static unsigned long __init kernel_physical_mapping_init(unsigned long start,
600 unsigned long end,
601 unsigned long page_size_mask)
602 {
603
604 unsigned long next, last_map_addr = end;
605
606 start = (unsigned long)__va(start);
607 end = (unsigned long)__va(end);
608
609 for (; start < end; start = next) {
610 pgd_t *pgd = pgd_offset_k(start);
611 unsigned long pud_phys;
612 pud_t *pud;
613
614 next = (start + PGDIR_SIZE) & PGDIR_MASK;
615 if (next > end)
616 next = end;
617
618 if (pgd_val(*pgd)) {
619 last_map_addr = phys_pud_update(pgd, __pa(start),
620 __pa(end), page_size_mask);
621 continue;
622 }
623
624 pud = alloc_low_page(&pud_phys);
625 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
626 page_size_mask);
627 unmap_low_page(pud);
628
629 spin_lock(&init_mm.page_table_lock);
630 pgd_populate(&init_mm, pgd, __va(pud_phys));
631 spin_unlock(&init_mm.page_table_lock);
632 }
633 __flush_tlb_all();
634
635 return last_map_addr;
636 }
637
638 struct map_range {
639 unsigned long start;
640 unsigned long end;
641 unsigned page_size_mask;
642 };
643
644 #define NR_RANGE_MR 5
645
646 static int save_mr(struct map_range *mr, int nr_range,
647 unsigned long start_pfn, unsigned long end_pfn,
648 unsigned long page_size_mask)
649 {
650
651 if (start_pfn < end_pfn) {
652 if (nr_range >= NR_RANGE_MR)
653 panic("run out of range for init_memory_mapping\n");
654 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
655 mr[nr_range].end = end_pfn<<PAGE_SHIFT;
656 mr[nr_range].page_size_mask = page_size_mask;
657 nr_range++;
658 }
659
660 return nr_range;
661 }
662
663 /*
664 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
665 * This runs before bootmem is initialized and gets pages directly from
666 * the physical memory. To access them they are temporarily mapped.
667 */
668 unsigned long __init_refok init_memory_mapping(unsigned long start,
669 unsigned long end)
670 {
671 unsigned long last_map_addr = 0;
672 unsigned long page_size_mask = 0;
673 unsigned long start_pfn, end_pfn;
674
675 struct map_range mr[NR_RANGE_MR];
676 int nr_range, i;
677 int use_pse, use_gbpages;
678
679 printk(KERN_INFO "init_memory_mapping\n");
680
681 /*
682 * Find space for the kernel direct mapping tables.
683 *
684 * Later we should allocate these tables in the local node of the
685 * memory mapped. Unfortunately this is done currently before the
686 * nodes are discovered.
687 */
688 if (!after_bootmem)
689 init_gbpages();
690
691 #ifdef CONFIG_DEBUG_PAGEALLOC
692 /*
693 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
694 * This will simplify cpa(), which otherwise needs to support splitting
695 * large pages into small in interrupt context, etc.
696 */
697 use_pse = use_gbpages = 0;
698 #else
699 use_pse = cpu_has_pse;
700 use_gbpages = direct_gbpages;
701 #endif
702
703 if (use_gbpages)
704 page_size_mask |= 1 << PG_LEVEL_1G;
705 if (use_pse)
706 page_size_mask |= 1 << PG_LEVEL_2M;
707
708 memset(mr, 0, sizeof(mr));
709 nr_range = 0;
710
711 /* head if not big page alignment ?*/
712 start_pfn = start >> PAGE_SHIFT;
713 end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
714 << (PMD_SHIFT - PAGE_SHIFT);
715 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
716
717 /* big page (2M) range*/
718 start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
719 << (PMD_SHIFT - PAGE_SHIFT);
720 end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT)
721 << (PUD_SHIFT - PAGE_SHIFT);
722 if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
723 end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
724 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
725 page_size_mask & (1<<PG_LEVEL_2M));
726
727 /* big page (1G) range */
728 start_pfn = end_pfn;
729 end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
730 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
731 page_size_mask &
732 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
733
734 /* tail is not big page (1G) alignment */
735 start_pfn = end_pfn;
736 end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
737 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
738 page_size_mask & (1<<PG_LEVEL_2M));
739
740 /* tail is not big page (2M) alignment */
741 start_pfn = end_pfn;
742 end_pfn = end>>PAGE_SHIFT;
743 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
744
745 /* try to merge same page size and continuous */
746 for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
747 unsigned long old_start;
748 if (mr[i].end != mr[i+1].start ||
749 mr[i].page_size_mask != mr[i+1].page_size_mask)
750 continue;
751 /* move it */
752 old_start = mr[i].start;
753 memmove(&mr[i], &mr[i+1],
754 (nr_range - 1 - i) * sizeof (struct map_range));
755 mr[i--].start = old_start;
756 nr_range--;
757 }
758
759 for (i = 0; i < nr_range; i++)
760 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
761 mr[i].start, mr[i].end,
762 (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
763 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
764
765 if (!after_bootmem)
766 find_early_table_space(end, use_pse, use_gbpages);
767
768 for (i = 0; i < nr_range; i++)
769 last_map_addr = kernel_physical_mapping_init(
770 mr[i].start, mr[i].end,
771 mr[i].page_size_mask);
772
773 if (!after_bootmem)
774 mmu_cr4_features = read_cr4();
775 __flush_tlb_all();
776
777 if (!after_bootmem && table_end > table_start)
778 reserve_early(table_start << PAGE_SHIFT,
779 table_end << PAGE_SHIFT, "PGTABLE");
780
781 printk(KERN_INFO "last_map_addr: %lx end: %lx\n",
782 last_map_addr, end);
783
784 if (!after_bootmem)
785 early_memtest(start, end);
786
787 return last_map_addr >> PAGE_SHIFT;
788 }
789
790 #ifndef CONFIG_NUMA
791 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
792 {
793 unsigned long bootmap_size, bootmap;
794
795 bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
796 bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
797 PAGE_SIZE);
798 if (bootmap == -1L)
799 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
800 /* don't touch min_low_pfn */
801 bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
802 0, end_pfn);
803 e820_register_active_regions(0, start_pfn, end_pfn);
804 free_bootmem_with_active_regions(0, end_pfn);
805 early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
806 reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
807 }
808
809 void __init paging_init(void)
810 {
811 unsigned long max_zone_pfns[MAX_NR_ZONES];
812
813 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
814 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
815 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
816 max_zone_pfns[ZONE_NORMAL] = max_pfn;
817
818 memory_present(0, 0, max_pfn);
819 sparse_init();
820 free_area_init_nodes(max_zone_pfns);
821 }
822 #endif
823
824 /*
825 * Memory hotplug specific functions
826 */
827 #ifdef CONFIG_MEMORY_HOTPLUG
828 /*
829 * Memory is added always to NORMAL zone. This means you will never get
830 * additional DMA/DMA32 memory.
831 */
832 int arch_add_memory(int nid, u64 start, u64 size)
833 {
834 struct pglist_data *pgdat = NODE_DATA(nid);
835 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
836 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
837 unsigned long nr_pages = size >> PAGE_SHIFT;
838 int ret;
839
840 last_mapped_pfn = init_memory_mapping(start, start + size);
841 if (last_mapped_pfn > max_pfn_mapped)
842 max_pfn_mapped = last_mapped_pfn;
843
844 ret = __add_pages(zone, start_pfn, nr_pages);
845 WARN_ON(1);
846
847 return ret;
848 }
849 EXPORT_SYMBOL_GPL(arch_add_memory);
850
851 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
852 int memory_add_physaddr_to_nid(u64 start)
853 {
854 return 0;
855 }
856 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
857 #endif
858
859 #endif /* CONFIG_MEMORY_HOTPLUG */
860
861 /*
862 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
863 * is valid. The argument is a physical page number.
864 *
865 *
866 * On x86, access has to be given to the first megabyte of ram because that area
867 * contains bios code and data regions used by X and dosemu and similar apps.
868 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
869 * mmio resources as well as potential bios/acpi data regions.
870 */
871 int devmem_is_allowed(unsigned long pagenr)
872 {
873 if (pagenr <= 256)
874 return 1;
875 if (!page_is_ram(pagenr))
876 return 1;
877 return 0;
878 }
879
880
881 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
882 kcore_modules, kcore_vsyscall;
883
884 void __init mem_init(void)
885 {
886 long codesize, reservedpages, datasize, initsize;
887
888 start_periodic_check_for_corruption();
889
890 pci_iommu_alloc();
891
892 /* clear_bss() already clear the empty_zero_page */
893
894 reservedpages = 0;
895
896 /* this will put all low memory onto the freelists */
897 #ifdef CONFIG_NUMA
898 totalram_pages = numa_free_all_bootmem();
899 #else
900 totalram_pages = free_all_bootmem();
901 #endif
902 reservedpages = max_pfn - totalram_pages -
903 absent_pages_in_range(0, max_pfn);
904 after_bootmem = 1;
905
906 codesize = (unsigned long) &_etext - (unsigned long) &_text;
907 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
908 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
909
910 /* Register memory areas for /proc/kcore */
911 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
912 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
913 VMALLOC_END-VMALLOC_START);
914 kclist_add(&kcore_kernel, &_stext, _end - _stext);
915 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
916 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
917 VSYSCALL_END - VSYSCALL_START);
918
919 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
920 "%ldk reserved, %ldk data, %ldk init)\n",
921 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
922 max_pfn << (PAGE_SHIFT-10),
923 codesize >> 10,
924 reservedpages << (PAGE_SHIFT-10),
925 datasize >> 10,
926 initsize >> 10);
927 }
928
929 void free_init_pages(char *what, unsigned long begin, unsigned long end)
930 {
931 unsigned long addr = begin;
932
933 if (addr >= end)
934 return;
935
936 /*
937 * If debugging page accesses then do not free this memory but
938 * mark them not present - any buggy init-section access will
939 * create a kernel page fault:
940 */
941 #ifdef CONFIG_DEBUG_PAGEALLOC
942 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
943 begin, PAGE_ALIGN(end));
944 set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
945 #else
946 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
947
948 for (; addr < end; addr += PAGE_SIZE) {
949 ClearPageReserved(virt_to_page(addr));
950 init_page_count(virt_to_page(addr));
951 memset((void *)(addr & ~(PAGE_SIZE-1)),
952 POISON_FREE_INITMEM, PAGE_SIZE);
953 free_page(addr);
954 totalram_pages++;
955 }
956 #endif
957 }
958
959 void free_initmem(void)
960 {
961 free_init_pages("unused kernel memory",
962 (unsigned long)(&__init_begin),
963 (unsigned long)(&__init_end));
964 }
965
966 #ifdef CONFIG_DEBUG_RODATA
967 const int rodata_test_data = 0xC3;
968 EXPORT_SYMBOL_GPL(rodata_test_data);
969
970 void mark_rodata_ro(void)
971 {
972 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
973 unsigned long rodata_start =
974 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
975
976 #ifdef CONFIG_DYNAMIC_FTRACE
977 /* Dynamic tracing modifies the kernel text section */
978 start = rodata_start;
979 #endif
980
981 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
982 (end - start) >> 10);
983 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
984
985 /*
986 * The rodata section (but not the kernel text!) should also be
987 * not-executable.
988 */
989 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
990
991 rodata_test();
992
993 #ifdef CONFIG_CPA_DEBUG
994 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
995 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
996
997 printk(KERN_INFO "Testing CPA: again\n");
998 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
999 #endif
1000 }
1001
1002 #endif
1003
1004 #ifdef CONFIG_BLK_DEV_INITRD
1005 void free_initrd_mem(unsigned long start, unsigned long end)
1006 {
1007 free_init_pages("initrd memory", start, end);
1008 }
1009 #endif
1010
1011 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
1012 int flags)
1013 {
1014 #ifdef CONFIG_NUMA
1015 int nid, next_nid;
1016 int ret;
1017 #endif
1018 unsigned long pfn = phys >> PAGE_SHIFT;
1019
1020 if (pfn >= max_pfn) {
1021 /*
1022 * This can happen with kdump kernels when accessing
1023 * firmware tables:
1024 */
1025 if (pfn < max_pfn_mapped)
1026 return -EFAULT;
1027
1028 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
1029 phys, len);
1030 return -EFAULT;
1031 }
1032
1033 /* Should check here against the e820 map to avoid double free */
1034 #ifdef CONFIG_NUMA
1035 nid = phys_to_nid(phys);
1036 next_nid = phys_to_nid(phys + len - 1);
1037 if (nid == next_nid)
1038 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
1039 else
1040 ret = reserve_bootmem(phys, len, flags);
1041
1042 if (ret != 0)
1043 return ret;
1044
1045 #else
1046 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
1047 #endif
1048
1049 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
1050 dma_reserve += len / PAGE_SIZE;
1051 set_dma_reserve(dma_reserve);
1052 }
1053
1054 return 0;
1055 }
1056
1057 int kern_addr_valid(unsigned long addr)
1058 {
1059 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1060 pgd_t *pgd;
1061 pud_t *pud;
1062 pmd_t *pmd;
1063 pte_t *pte;
1064
1065 if (above != 0 && above != -1UL)
1066 return 0;
1067
1068 pgd = pgd_offset_k(addr);
1069 if (pgd_none(*pgd))
1070 return 0;
1071
1072 pud = pud_offset(pgd, addr);
1073 if (pud_none(*pud))
1074 return 0;
1075
1076 pmd = pmd_offset(pud, addr);
1077 if (pmd_none(*pmd))
1078 return 0;
1079
1080 if (pmd_large(*pmd))
1081 return pfn_valid(pmd_pfn(*pmd));
1082
1083 pte = pte_offset_kernel(pmd, addr);
1084 if (pte_none(*pte))
1085 return 0;
1086
1087 return pfn_valid(pte_pfn(*pte));
1088 }
1089
1090 /*
1091 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
1092 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1093 * not need special handling anymore:
1094 */
1095 static struct vm_area_struct gate_vma = {
1096 .vm_start = VSYSCALL_START,
1097 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
1098 .vm_page_prot = PAGE_READONLY_EXEC,
1099 .vm_flags = VM_READ | VM_EXEC
1100 };
1101
1102 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
1103 {
1104 #ifdef CONFIG_IA32_EMULATION
1105 if (test_tsk_thread_flag(tsk, TIF_IA32))
1106 return NULL;
1107 #endif
1108 return &gate_vma;
1109 }
1110
1111 int in_gate_area(struct task_struct *task, unsigned long addr)
1112 {
1113 struct vm_area_struct *vma = get_gate_vma(task);
1114
1115 if (!vma)
1116 return 0;
1117
1118 return (addr >= vma->vm_start) && (addr < vma->vm_end);
1119 }
1120
1121 /*
1122 * Use this when you have no reliable task/vma, typically from interrupt
1123 * context. It is less reliable than using the task's vma and may give
1124 * false positives:
1125 */
1126 int in_gate_area_no_task(unsigned long addr)
1127 {
1128 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1129 }
1130
1131 const char *arch_vma_name(struct vm_area_struct *vma)
1132 {
1133 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1134 return "[vdso]";
1135 if (vma == &gate_vma)
1136 return "[vsyscall]";
1137 return NULL;
1138 }
1139
1140 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1141 /*
1142 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1143 */
1144 static long __meminitdata addr_start, addr_end;
1145 static void __meminitdata *p_start, *p_end;
1146 static int __meminitdata node_start;
1147
1148 int __meminit
1149 vmemmap_populate(struct page *start_page, unsigned long size, int node)
1150 {
1151 unsigned long addr = (unsigned long)start_page;
1152 unsigned long end = (unsigned long)(start_page + size);
1153 unsigned long next;
1154 pgd_t *pgd;
1155 pud_t *pud;
1156 pmd_t *pmd;
1157
1158 for (; addr < end; addr = next) {
1159 void *p = NULL;
1160
1161 pgd = vmemmap_pgd_populate(addr, node);
1162 if (!pgd)
1163 return -ENOMEM;
1164
1165 pud = vmemmap_pud_populate(pgd, addr, node);
1166 if (!pud)
1167 return -ENOMEM;
1168
1169 if (!cpu_has_pse) {
1170 next = (addr + PAGE_SIZE) & PAGE_MASK;
1171 pmd = vmemmap_pmd_populate(pud, addr, node);
1172
1173 if (!pmd)
1174 return -ENOMEM;
1175
1176 p = vmemmap_pte_populate(pmd, addr, node);
1177
1178 if (!p)
1179 return -ENOMEM;
1180
1181 addr_end = addr + PAGE_SIZE;
1182 p_end = p + PAGE_SIZE;
1183 } else {
1184 next = pmd_addr_end(addr, end);
1185
1186 pmd = pmd_offset(pud, addr);
1187 if (pmd_none(*pmd)) {
1188 pte_t entry;
1189
1190 p = vmemmap_alloc_block(PMD_SIZE, node);
1191 if (!p)
1192 return -ENOMEM;
1193
1194 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1195 PAGE_KERNEL_LARGE);
1196 set_pmd(pmd, __pmd(pte_val(entry)));
1197
1198 /* check to see if we have contiguous blocks */
1199 if (p_end != p || node_start != node) {
1200 if (p_start)
1201 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1202 addr_start, addr_end-1, p_start, p_end-1, node_start);
1203 addr_start = addr;
1204 node_start = node;
1205 p_start = p;
1206 }
1207
1208 addr_end = addr + PMD_SIZE;
1209 p_end = p + PMD_SIZE;
1210 } else
1211 vmemmap_verify((pte_t *)pmd, node, addr, next);
1212 }
1213
1214 }
1215 return 0;
1216 }
1217
1218 void __meminit vmemmap_populate_print_last(void)
1219 {
1220 if (p_start) {
1221 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1222 addr_start, addr_end-1, p_start, p_end-1, node_start);
1223 p_start = NULL;
1224 p_end = NULL;
1225 node_start = 0;
1226 }
1227 }
1228 #endif
kernel-based virtual machine