x86: use sparse_memory_present_with_active_regions() on UMA
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / x86 / mm / init_64.c
blob52bb9519bb86b4ec778d613939ea658adb1052a6
1 /*
2 * linux/arch/x86_64/mm/init.c
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 */
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>
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 #include <asm/init.h>
53 static unsigned long dma_reserve __initdata;
55 static int __init parse_direct_gbpages_off(char *arg)
57 direct_gbpages = 0;
58 return 0;
60 early_param("nogbpages", parse_direct_gbpages_off);
62 static int __init parse_direct_gbpages_on(char *arg)
64 direct_gbpages = 1;
65 return 0;
67 early_param("gbpages", parse_direct_gbpages_on);
70 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
71 * physical space so we can cache the place of the first one and move
72 * around without checking the pgd every time.
75 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
76 EXPORT_SYMBOL_GPL(__supported_pte_mask);
78 int force_personality32;
81 * noexec32=on|off
82 * Control non executable heap for 32bit processes.
83 * To control the stack too use noexec=off
85 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
86 * off PROT_READ implies PROT_EXEC
88 static int __init nonx32_setup(char *str)
90 if (!strcmp(str, "on"))
91 force_personality32 &= ~READ_IMPLIES_EXEC;
92 else if (!strcmp(str, "off"))
93 force_personality32 |= READ_IMPLIES_EXEC;
94 return 1;
96 __setup("noexec32=", nonx32_setup);
99 * NOTE: This function is marked __ref because it calls __init function
100 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
102 static __ref void *spp_getpage(void)
104 void *ptr;
106 if (after_bootmem)
107 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
108 else
109 ptr = alloc_bootmem_pages(PAGE_SIZE);
111 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
112 panic("set_pte_phys: cannot allocate page data %s\n",
113 after_bootmem ? "after bootmem" : "");
116 pr_debug("spp_getpage %p\n", ptr);
118 return ptr;
121 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
123 if (pgd_none(*pgd)) {
124 pud_t *pud = (pud_t *)spp_getpage();
125 pgd_populate(&init_mm, pgd, pud);
126 if (pud != pud_offset(pgd, 0))
127 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
128 pud, pud_offset(pgd, 0));
130 return pud_offset(pgd, vaddr);
133 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
135 if (pud_none(*pud)) {
136 pmd_t *pmd = (pmd_t *) spp_getpage();
137 pud_populate(&init_mm, pud, pmd);
138 if (pmd != pmd_offset(pud, 0))
139 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
140 pmd, pmd_offset(pud, 0));
142 return pmd_offset(pud, vaddr);
145 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
147 if (pmd_none(*pmd)) {
148 pte_t *pte = (pte_t *) spp_getpage();
149 pmd_populate_kernel(&init_mm, pmd, pte);
150 if (pte != pte_offset_kernel(pmd, 0))
151 printk(KERN_ERR "PAGETABLE BUG #02!\n");
153 return pte_offset_kernel(pmd, vaddr);
156 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
158 pud_t *pud;
159 pmd_t *pmd;
160 pte_t *pte;
162 pud = pud_page + pud_index(vaddr);
163 pmd = fill_pmd(pud, vaddr);
164 pte = fill_pte(pmd, vaddr);
166 set_pte(pte, new_pte);
169 * It's enough to flush this one mapping.
170 * (PGE mappings get flushed as well)
172 __flush_tlb_one(vaddr);
175 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
177 pgd_t *pgd;
178 pud_t *pud_page;
180 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
182 pgd = pgd_offset_k(vaddr);
183 if (pgd_none(*pgd)) {
184 printk(KERN_ERR
185 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
186 return;
188 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
189 set_pte_vaddr_pud(pud_page, vaddr, pteval);
192 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
194 pgd_t *pgd;
195 pud_t *pud;
197 pgd = pgd_offset_k(vaddr);
198 pud = fill_pud(pgd, vaddr);
199 return fill_pmd(pud, vaddr);
202 pte_t * __init populate_extra_pte(unsigned long vaddr)
204 pmd_t *pmd;
206 pmd = populate_extra_pmd(vaddr);
207 return fill_pte(pmd, vaddr);
211 * Create large page table mappings for a range of physical addresses.
213 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
214 pgprot_t prot)
216 pgd_t *pgd;
217 pud_t *pud;
218 pmd_t *pmd;
220 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
221 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
222 pgd = pgd_offset_k((unsigned long)__va(phys));
223 if (pgd_none(*pgd)) {
224 pud = (pud_t *) spp_getpage();
225 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
226 _PAGE_USER));
228 pud = pud_offset(pgd, (unsigned long)__va(phys));
229 if (pud_none(*pud)) {
230 pmd = (pmd_t *) spp_getpage();
231 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
232 _PAGE_USER));
234 pmd = pmd_offset(pud, phys);
235 BUG_ON(!pmd_none(*pmd));
236 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
240 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
242 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
245 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
247 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
251 * The head.S code sets up the kernel high mapping:
253 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
255 * phys_addr holds the negative offset to the kernel, which is added
256 * to the compile time generated pmds. This results in invalid pmds up
257 * to the point where we hit the physaddr 0 mapping.
259 * We limit the mappings to the region from _text to _end. _end is
260 * rounded up to the 2MB boundary. This catches the invalid pmds as
261 * well, as they are located before _text:
263 void __init cleanup_highmap(void)
265 unsigned long vaddr = __START_KERNEL_map;
266 unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
267 pmd_t *pmd = level2_kernel_pgt;
268 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
270 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
271 if (pmd_none(*pmd))
272 continue;
273 if (vaddr < (unsigned long) _text || vaddr > end)
274 set_pmd(pmd, __pmd(0));
278 static __ref void *alloc_low_page(unsigned long *phys)
280 unsigned long pfn = e820_table_end++;
281 void *adr;
283 if (after_bootmem) {
284 adr = (void *)get_zeroed_page(GFP_ATOMIC);
285 *phys = __pa(adr);
287 return adr;
290 if (pfn >= e820_table_top)
291 panic("alloc_low_page: ran out of memory");
293 adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
294 memset(adr, 0, PAGE_SIZE);
295 *phys = pfn * PAGE_SIZE;
296 return adr;
299 static __ref void unmap_low_page(void *adr)
301 if (after_bootmem)
302 return;
304 early_iounmap(adr, PAGE_SIZE);
307 static unsigned long __meminit
308 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
309 pgprot_t prot)
311 unsigned pages = 0;
312 unsigned long last_map_addr = end;
313 int i;
315 pte_t *pte = pte_page + pte_index(addr);
317 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
319 if (addr >= end) {
320 if (!after_bootmem) {
321 for(; i < PTRS_PER_PTE; i++, pte++)
322 set_pte(pte, __pte(0));
324 break;
328 * We will re-use the existing mapping.
329 * Xen for example has some special requirements, like mapping
330 * pagetable pages as RO. So assume someone who pre-setup
331 * these mappings are more intelligent.
333 if (pte_val(*pte)) {
334 pages++;
335 continue;
338 if (0)
339 printk(" pte=%p addr=%lx pte=%016lx\n",
340 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
341 pages++;
342 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
343 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
346 update_page_count(PG_LEVEL_4K, pages);
348 return last_map_addr;
351 static unsigned long __meminit
352 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end,
353 pgprot_t prot)
355 pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
357 return phys_pte_init(pte, address, end, prot);
360 static unsigned long __meminit
361 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
362 unsigned long page_size_mask, pgprot_t prot)
364 unsigned long pages = 0;
365 unsigned long last_map_addr = end;
367 int i = pmd_index(address);
369 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
370 unsigned long pte_phys;
371 pmd_t *pmd = pmd_page + pmd_index(address);
372 pte_t *pte;
373 pgprot_t new_prot = prot;
375 if (address >= end) {
376 if (!after_bootmem) {
377 for (; i < PTRS_PER_PMD; i++, pmd++)
378 set_pmd(pmd, __pmd(0));
380 break;
383 if (pmd_val(*pmd)) {
384 if (!pmd_large(*pmd)) {
385 spin_lock(&init_mm.page_table_lock);
386 last_map_addr = phys_pte_update(pmd, address,
387 end, prot);
388 spin_unlock(&init_mm.page_table_lock);
389 continue;
392 * If we are ok with PG_LEVEL_2M mapping, then we will
393 * use the existing mapping,
395 * Otherwise, we will split the large page mapping but
396 * use the same existing protection bits except for
397 * large page, so that we don't violate Intel's TLB
398 * Application note (317080) which says, while changing
399 * the page sizes, new and old translations should
400 * not differ with respect to page frame and
401 * attributes.
403 if (page_size_mask & (1 << PG_LEVEL_2M)) {
404 pages++;
405 continue;
407 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
410 if (page_size_mask & (1<<PG_LEVEL_2M)) {
411 pages++;
412 spin_lock(&init_mm.page_table_lock);
413 set_pte((pte_t *)pmd,
414 pfn_pte(address >> PAGE_SHIFT,
415 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
416 spin_unlock(&init_mm.page_table_lock);
417 last_map_addr = (address & PMD_MASK) + PMD_SIZE;
418 continue;
421 pte = alloc_low_page(&pte_phys);
422 last_map_addr = phys_pte_init(pte, address, end, new_prot);
423 unmap_low_page(pte);
425 spin_lock(&init_mm.page_table_lock);
426 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
427 spin_unlock(&init_mm.page_table_lock);
429 update_page_count(PG_LEVEL_2M, pages);
430 return last_map_addr;
433 static unsigned long __meminit
434 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
435 unsigned long page_size_mask, pgprot_t prot)
437 pmd_t *pmd = pmd_offset(pud, 0);
438 unsigned long last_map_addr;
440 last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot);
441 __flush_tlb_all();
442 return last_map_addr;
445 static unsigned long __meminit
446 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
447 unsigned long page_size_mask)
449 unsigned long pages = 0;
450 unsigned long last_map_addr = end;
451 int i = pud_index(addr);
453 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
454 unsigned long pmd_phys;
455 pud_t *pud = pud_page + pud_index(addr);
456 pmd_t *pmd;
457 pgprot_t prot = PAGE_KERNEL;
459 if (addr >= end)
460 break;
462 if (!after_bootmem &&
463 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
464 set_pud(pud, __pud(0));
465 continue;
468 if (pud_val(*pud)) {
469 if (!pud_large(*pud)) {
470 last_map_addr = phys_pmd_update(pud, addr, end,
471 page_size_mask, prot);
472 continue;
475 * If we are ok with PG_LEVEL_1G mapping, then we will
476 * use the existing mapping.
478 * Otherwise, we will split the gbpage mapping but use
479 * the same existing protection bits except for large
480 * page, so that we don't violate Intel's TLB
481 * Application note (317080) which says, while changing
482 * the page sizes, new and old translations should
483 * not differ with respect to page frame and
484 * attributes.
486 if (page_size_mask & (1 << PG_LEVEL_1G)) {
487 pages++;
488 continue;
490 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
493 if (page_size_mask & (1<<PG_LEVEL_1G)) {
494 pages++;
495 spin_lock(&init_mm.page_table_lock);
496 set_pte((pte_t *)pud,
497 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
498 spin_unlock(&init_mm.page_table_lock);
499 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
500 continue;
503 pmd = alloc_low_page(&pmd_phys);
504 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
505 prot);
506 unmap_low_page(pmd);
508 spin_lock(&init_mm.page_table_lock);
509 pud_populate(&init_mm, pud, __va(pmd_phys));
510 spin_unlock(&init_mm.page_table_lock);
512 __flush_tlb_all();
514 update_page_count(PG_LEVEL_1G, pages);
516 return last_map_addr;
519 static unsigned long __meminit
520 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
521 unsigned long page_size_mask)
523 pud_t *pud;
525 pud = (pud_t *)pgd_page_vaddr(*pgd);
527 return phys_pud_init(pud, addr, end, page_size_mask);
530 unsigned long __init
531 kernel_physical_mapping_init(unsigned long start,
532 unsigned long end,
533 unsigned long page_size_mask)
536 unsigned long next, last_map_addr = end;
538 start = (unsigned long)__va(start);
539 end = (unsigned long)__va(end);
541 for (; start < end; start = next) {
542 pgd_t *pgd = pgd_offset_k(start);
543 unsigned long pud_phys;
544 pud_t *pud;
546 next = (start + PGDIR_SIZE) & PGDIR_MASK;
547 if (next > end)
548 next = end;
550 if (pgd_val(*pgd)) {
551 last_map_addr = phys_pud_update(pgd, __pa(start),
552 __pa(end), page_size_mask);
553 continue;
556 pud = alloc_low_page(&pud_phys);
557 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
558 page_size_mask);
559 unmap_low_page(pud);
561 spin_lock(&init_mm.page_table_lock);
562 pgd_populate(&init_mm, pgd, __va(pud_phys));
563 spin_unlock(&init_mm.page_table_lock);
565 __flush_tlb_all();
567 return last_map_addr;
570 #ifndef CONFIG_NUMA
571 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
573 unsigned long bootmap_size, bootmap;
575 bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
576 bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
577 PAGE_SIZE);
578 if (bootmap == -1L)
579 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
580 /* don't touch min_low_pfn */
581 bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
582 0, end_pfn);
583 e820_register_active_regions(0, start_pfn, end_pfn);
584 free_bootmem_with_active_regions(0, end_pfn);
585 early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
586 reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
588 #endif
590 void __init paging_init(void)
592 unsigned long max_zone_pfns[MAX_NR_ZONES];
594 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
595 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
596 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
597 max_zone_pfns[ZONE_NORMAL] = max_pfn;
599 sparse_memory_present_with_active_regions(MAX_NUMNODES);
600 sparse_init();
601 free_area_init_nodes(max_zone_pfns);
605 * Memory hotplug specific functions
607 #ifdef CONFIG_MEMORY_HOTPLUG
609 * Memory is added always to NORMAL zone. This means you will never get
610 * additional DMA/DMA32 memory.
612 int arch_add_memory(int nid, u64 start, u64 size)
614 struct pglist_data *pgdat = NODE_DATA(nid);
615 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
616 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
617 unsigned long nr_pages = size >> PAGE_SHIFT;
618 int ret;
620 last_mapped_pfn = init_memory_mapping(start, start + size);
621 if (last_mapped_pfn > max_pfn_mapped)
622 max_pfn_mapped = last_mapped_pfn;
624 ret = __add_pages(nid, zone, start_pfn, nr_pages);
625 WARN_ON_ONCE(ret);
627 return ret;
629 EXPORT_SYMBOL_GPL(arch_add_memory);
631 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
632 int memory_add_physaddr_to_nid(u64 start)
634 return 0;
636 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
637 #endif
639 #endif /* CONFIG_MEMORY_HOTPLUG */
641 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
642 kcore_modules, kcore_vsyscall;
644 void __init mem_init(void)
646 long codesize, reservedpages, datasize, initsize;
647 unsigned long absent_pages;
649 pci_iommu_alloc();
651 /* clear_bss() already clear the empty_zero_page */
653 reservedpages = 0;
655 /* this will put all low memory onto the freelists */
656 #ifdef CONFIG_NUMA
657 totalram_pages = numa_free_all_bootmem();
658 #else
659 totalram_pages = free_all_bootmem();
660 #endif
662 absent_pages = absent_pages_in_range(0, max_pfn);
663 reservedpages = max_pfn - totalram_pages - absent_pages;
664 after_bootmem = 1;
666 codesize = (unsigned long) &_etext - (unsigned long) &_text;
667 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
668 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
670 /* Register memory areas for /proc/kcore */
671 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
672 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
673 VMALLOC_END-VMALLOC_START);
674 kclist_add(&kcore_kernel, &_stext, _end - _stext);
675 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
676 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
677 VSYSCALL_END - VSYSCALL_START);
679 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
680 "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n",
681 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
682 max_pfn << (PAGE_SHIFT-10),
683 codesize >> 10,
684 absent_pages << (PAGE_SHIFT-10),
685 reservedpages << (PAGE_SHIFT-10),
686 datasize >> 10,
687 initsize >> 10);
690 #ifdef CONFIG_DEBUG_RODATA
691 const int rodata_test_data = 0xC3;
692 EXPORT_SYMBOL_GPL(rodata_test_data);
694 static int kernel_set_to_readonly;
696 void set_kernel_text_rw(void)
698 unsigned long start = PFN_ALIGN(_stext);
699 unsigned long end = PFN_ALIGN(__start_rodata);
701 if (!kernel_set_to_readonly)
702 return;
704 pr_debug("Set kernel text: %lx - %lx for read write\n",
705 start, end);
707 set_memory_rw(start, (end - start) >> PAGE_SHIFT);
710 void set_kernel_text_ro(void)
712 unsigned long start = PFN_ALIGN(_stext);
713 unsigned long end = PFN_ALIGN(__start_rodata);
715 if (!kernel_set_to_readonly)
716 return;
718 pr_debug("Set kernel text: %lx - %lx for read only\n",
719 start, end);
721 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
724 void mark_rodata_ro(void)
726 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
727 unsigned long rodata_start =
728 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
730 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
731 (end - start) >> 10);
732 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
734 kernel_set_to_readonly = 1;
737 * The rodata section (but not the kernel text!) should also be
738 * not-executable.
740 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
742 rodata_test();
744 #ifdef CONFIG_CPA_DEBUG
745 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
746 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
748 printk(KERN_INFO "Testing CPA: again\n");
749 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
750 #endif
753 #endif
755 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
756 int flags)
758 #ifdef CONFIG_NUMA
759 int nid, next_nid;
760 int ret;
761 #endif
762 unsigned long pfn = phys >> PAGE_SHIFT;
764 if (pfn >= max_pfn) {
766 * This can happen with kdump kernels when accessing
767 * firmware tables:
769 if (pfn < max_pfn_mapped)
770 return -EFAULT;
772 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
773 phys, len);
774 return -EFAULT;
777 /* Should check here against the e820 map to avoid double free */
778 #ifdef CONFIG_NUMA
779 nid = phys_to_nid(phys);
780 next_nid = phys_to_nid(phys + len - 1);
781 if (nid == next_nid)
782 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
783 else
784 ret = reserve_bootmem(phys, len, flags);
786 if (ret != 0)
787 return ret;
789 #else
790 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
791 #endif
793 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
794 dma_reserve += len / PAGE_SIZE;
795 set_dma_reserve(dma_reserve);
798 return 0;
801 int kern_addr_valid(unsigned long addr)
803 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
804 pgd_t *pgd;
805 pud_t *pud;
806 pmd_t *pmd;
807 pte_t *pte;
809 if (above != 0 && above != -1UL)
810 return 0;
812 pgd = pgd_offset_k(addr);
813 if (pgd_none(*pgd))
814 return 0;
816 pud = pud_offset(pgd, addr);
817 if (pud_none(*pud))
818 return 0;
820 pmd = pmd_offset(pud, addr);
821 if (pmd_none(*pmd))
822 return 0;
824 if (pmd_large(*pmd))
825 return pfn_valid(pmd_pfn(*pmd));
827 pte = pte_offset_kernel(pmd, addr);
828 if (pte_none(*pte))
829 return 0;
831 return pfn_valid(pte_pfn(*pte));
835 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
836 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
837 * not need special handling anymore:
839 static struct vm_area_struct gate_vma = {
840 .vm_start = VSYSCALL_START,
841 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
842 .vm_page_prot = PAGE_READONLY_EXEC,
843 .vm_flags = VM_READ | VM_EXEC
846 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
848 #ifdef CONFIG_IA32_EMULATION
849 if (test_tsk_thread_flag(tsk, TIF_IA32))
850 return NULL;
851 #endif
852 return &gate_vma;
855 int in_gate_area(struct task_struct *task, unsigned long addr)
857 struct vm_area_struct *vma = get_gate_vma(task);
859 if (!vma)
860 return 0;
862 return (addr >= vma->vm_start) && (addr < vma->vm_end);
866 * Use this when you have no reliable task/vma, typically from interrupt
867 * context. It is less reliable than using the task's vma and may give
868 * false positives:
870 int in_gate_area_no_task(unsigned long addr)
872 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
875 const char *arch_vma_name(struct vm_area_struct *vma)
877 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
878 return "[vdso]";
879 if (vma == &gate_vma)
880 return "[vsyscall]";
881 return NULL;
884 #ifdef CONFIG_SPARSEMEM_VMEMMAP
886 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
888 static long __meminitdata addr_start, addr_end;
889 static void __meminitdata *p_start, *p_end;
890 static int __meminitdata node_start;
892 int __meminit
893 vmemmap_populate(struct page *start_page, unsigned long size, int node)
895 unsigned long addr = (unsigned long)start_page;
896 unsigned long end = (unsigned long)(start_page + size);
897 unsigned long next;
898 pgd_t *pgd;
899 pud_t *pud;
900 pmd_t *pmd;
902 for (; addr < end; addr = next) {
903 void *p = NULL;
905 pgd = vmemmap_pgd_populate(addr, node);
906 if (!pgd)
907 return -ENOMEM;
909 pud = vmemmap_pud_populate(pgd, addr, node);
910 if (!pud)
911 return -ENOMEM;
913 if (!cpu_has_pse) {
914 next = (addr + PAGE_SIZE) & PAGE_MASK;
915 pmd = vmemmap_pmd_populate(pud, addr, node);
917 if (!pmd)
918 return -ENOMEM;
920 p = vmemmap_pte_populate(pmd, addr, node);
922 if (!p)
923 return -ENOMEM;
925 addr_end = addr + PAGE_SIZE;
926 p_end = p + PAGE_SIZE;
927 } else {
928 next = pmd_addr_end(addr, end);
930 pmd = pmd_offset(pud, addr);
931 if (pmd_none(*pmd)) {
932 pte_t entry;
934 p = vmemmap_alloc_block(PMD_SIZE, node);
935 if (!p)
936 return -ENOMEM;
938 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
939 PAGE_KERNEL_LARGE);
940 set_pmd(pmd, __pmd(pte_val(entry)));
942 /* check to see if we have contiguous blocks */
943 if (p_end != p || node_start != node) {
944 if (p_start)
945 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
946 addr_start, addr_end-1, p_start, p_end-1, node_start);
947 addr_start = addr;
948 node_start = node;
949 p_start = p;
952 addr_end = addr + PMD_SIZE;
953 p_end = p + PMD_SIZE;
954 } else
955 vmemmap_verify((pte_t *)pmd, node, addr, next);
959 return 0;
962 void __meminit vmemmap_populate_print_last(void)
964 if (p_start) {
965 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
966 addr_start, addr_end-1, p_start, p_end-1, node_start);
967 p_start = NULL;
968 p_end = NULL;
969 node_start = 0;
972 #endif