Merge branch 'tracing/ftrace' into auto-ftrace-next
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / x86 / mm / init_64.c
blob17c0a6138a53bd0bc84f7a2504bd85a612733c91
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/pagemap.h>
22 #include <linux/bootmem.h>
23 #include <linux/proc_fs.h>
24 #include <linux/pci.h>
25 #include <linux/pfn.h>
26 #include <linux/poison.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/module.h>
29 #include <linux/memory_hotplug.h>
30 #include <linux/nmi.h>
32 #include <asm/processor.h>
33 #include <asm/system.h>
34 #include <asm/uaccess.h>
35 #include <asm/pgtable.h>
36 #include <asm/pgalloc.h>
37 #include <asm/dma.h>
38 #include <asm/fixmap.h>
39 #include <asm/e820.h>
40 #include <asm/apic.h>
41 #include <asm/tlb.h>
42 #include <asm/mmu_context.h>
43 #include <asm/proto.h>
44 #include <asm/smp.h>
45 #include <asm/sections.h>
46 #include <asm/kdebug.h>
47 #include <asm/numa.h>
48 #include <asm/cacheflush.h>
50 static unsigned long dma_reserve __initdata;
52 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
54 int direct_gbpages __meminitdata
55 #ifdef CONFIG_DIRECT_GBPAGES
56 = 1
57 #endif
60 static int __init parse_direct_gbpages_off(char *arg)
62 direct_gbpages = 0;
63 return 0;
65 early_param("nogbpages", parse_direct_gbpages_off);
67 static int __init parse_direct_gbpages_on(char *arg)
69 direct_gbpages = 1;
70 return 0;
72 early_param("gbpages", parse_direct_gbpages_on);
75 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
76 * physical space so we can cache the place of the first one and move
77 * around without checking the pgd every time.
80 void show_mem(void)
82 long i, total = 0, reserved = 0;
83 long shared = 0, cached = 0;
84 struct page *page;
85 pg_data_t *pgdat;
87 printk(KERN_INFO "Mem-info:\n");
88 show_free_areas();
89 for_each_online_pgdat(pgdat) {
90 for (i = 0; i < pgdat->node_spanned_pages; ++i) {
92 * This loop can take a while with 256 GB and
93 * 4k pages so defer the NMI watchdog:
95 if (unlikely(i % MAX_ORDER_NR_PAGES == 0))
96 touch_nmi_watchdog();
98 if (!pfn_valid(pgdat->node_start_pfn + i))
99 continue;
101 page = pfn_to_page(pgdat->node_start_pfn + i);
102 total++;
103 if (PageReserved(page))
104 reserved++;
105 else if (PageSwapCache(page))
106 cached++;
107 else if (page_count(page))
108 shared += page_count(page) - 1;
111 printk(KERN_INFO "%lu pages of RAM\n", total);
112 printk(KERN_INFO "%lu reserved pages\n", reserved);
113 printk(KERN_INFO "%lu pages shared\n", shared);
114 printk(KERN_INFO "%lu pages swap cached\n", cached);
117 int after_bootmem;
119 static __init void *spp_getpage(void)
121 void *ptr;
123 if (after_bootmem)
124 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
125 else
126 ptr = alloc_bootmem_pages(PAGE_SIZE);
128 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
129 panic("set_pte_phys: cannot allocate page data %s\n",
130 after_bootmem ? "after bootmem" : "");
133 pr_debug("spp_getpage %p\n", ptr);
135 return ptr;
138 static __init void
139 set_pte_phys(unsigned long vaddr, unsigned long phys, pgprot_t prot)
141 pgd_t *pgd;
142 pud_t *pud;
143 pmd_t *pmd;
144 pte_t *pte, new_pte;
146 pr_debug("set_pte_phys %lx to %lx\n", vaddr, phys);
148 pgd = pgd_offset_k(vaddr);
149 if (pgd_none(*pgd)) {
150 printk(KERN_ERR
151 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
152 return;
154 pud = pud_offset(pgd, vaddr);
155 if (pud_none(*pud)) {
156 pmd = (pmd_t *) spp_getpage();
157 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | _PAGE_USER));
158 if (pmd != pmd_offset(pud, 0)) {
159 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
160 pmd, pmd_offset(pud, 0));
161 return;
164 pmd = pmd_offset(pud, vaddr);
165 if (pmd_none(*pmd)) {
166 pte = (pte_t *) spp_getpage();
167 set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER));
168 if (pte != pte_offset_kernel(pmd, 0)) {
169 printk(KERN_ERR "PAGETABLE BUG #02!\n");
170 return;
173 new_pte = pfn_pte(phys >> PAGE_SHIFT, prot);
175 pte = pte_offset_kernel(pmd, vaddr);
176 if (!pte_none(*pte) && pte_val(new_pte) &&
177 pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
178 pte_ERROR(*pte);
179 set_pte(pte, new_pte);
182 * It's enough to flush this one mapping.
183 * (PGE mappings get flushed as well)
185 __flush_tlb_one(vaddr);
189 * The head.S code sets up the kernel high mapping:
191 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
193 * phys_addr holds the negative offset to the kernel, which is added
194 * to the compile time generated pmds. This results in invalid pmds up
195 * to the point where we hit the physaddr 0 mapping.
197 * We limit the mappings to the region from _text to _end. _end is
198 * rounded up to the 2MB boundary. This catches the invalid pmds as
199 * well, as they are located before _text:
201 void __init cleanup_highmap(void)
203 unsigned long vaddr = __START_KERNEL_map;
204 unsigned long end = round_up((unsigned long)_end, PMD_SIZE) - 1;
205 pmd_t *pmd = level2_kernel_pgt;
206 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
208 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
209 if (pmd_none(*pmd))
210 continue;
211 if (vaddr < (unsigned long) _text || vaddr > end)
212 set_pmd(pmd, __pmd(0));
216 /* NOTE: this is meant to be run only at boot */
217 void __init __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
219 unsigned long address = __fix_to_virt(idx);
221 if (idx >= __end_of_fixed_addresses) {
222 printk(KERN_ERR "Invalid __set_fixmap\n");
223 return;
225 set_pte_phys(address, phys, prot);
228 static unsigned long __initdata table_start;
229 static unsigned long __meminitdata table_end;
231 static __meminit void *alloc_low_page(unsigned long *phys)
233 unsigned long pfn = table_end++;
234 void *adr;
236 if (after_bootmem) {
237 adr = (void *)get_zeroed_page(GFP_ATOMIC);
238 *phys = __pa(adr);
240 return adr;
243 if (pfn >= end_pfn)
244 panic("alloc_low_page: ran out of memory");
246 adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
247 memset(adr, 0, PAGE_SIZE);
248 *phys = pfn * PAGE_SIZE;
249 return adr;
252 static __meminit void unmap_low_page(void *adr)
254 if (after_bootmem)
255 return;
257 early_iounmap(adr, PAGE_SIZE);
260 /* Must run before zap_low_mappings */
261 __meminit void *early_ioremap(unsigned long addr, unsigned long size)
263 pmd_t *pmd, *last_pmd;
264 unsigned long vaddr;
265 int i, pmds;
267 pmds = ((addr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
268 vaddr = __START_KERNEL_map;
269 pmd = level2_kernel_pgt;
270 last_pmd = level2_kernel_pgt + PTRS_PER_PMD - 1;
272 for (; pmd <= last_pmd; pmd++, vaddr += PMD_SIZE) {
273 for (i = 0; i < pmds; i++) {
274 if (pmd_present(pmd[i]))
275 goto continue_outer_loop;
277 vaddr += addr & ~PMD_MASK;
278 addr &= PMD_MASK;
280 for (i = 0; i < pmds; i++, addr += PMD_SIZE)
281 set_pmd(pmd+i, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
282 __flush_tlb_all();
284 return (void *)vaddr;
285 continue_outer_loop:
288 printk(KERN_ERR "early_ioremap(0x%lx, %lu) failed\n", addr, size);
290 return NULL;
294 * To avoid virtual aliases later:
296 __meminit void early_iounmap(void *addr, unsigned long size)
298 unsigned long vaddr;
299 pmd_t *pmd;
300 int i, pmds;
302 vaddr = (unsigned long)addr;
303 pmds = ((vaddr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
304 pmd = level2_kernel_pgt + pmd_index(vaddr);
306 for (i = 0; i < pmds; i++)
307 pmd_clear(pmd + i);
309 __flush_tlb_all();
312 static unsigned long __meminit
313 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end)
315 int i = pmd_index(address);
317 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
318 pmd_t *pmd = pmd_page + pmd_index(address);
320 if (address >= end) {
321 if (!after_bootmem) {
322 for (; i < PTRS_PER_PMD; i++, pmd++)
323 set_pmd(pmd, __pmd(0));
325 break;
328 if (pmd_val(*pmd))
329 continue;
331 set_pte((pte_t *)pmd,
332 pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
334 return address;
337 static unsigned long __meminit
338 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end)
340 pmd_t *pmd = pmd_offset(pud, 0);
341 unsigned long last_map_addr;
343 spin_lock(&init_mm.page_table_lock);
344 last_map_addr = phys_pmd_init(pmd, address, end);
345 spin_unlock(&init_mm.page_table_lock);
346 __flush_tlb_all();
347 return last_map_addr;
350 static unsigned long __meminit
351 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end)
353 unsigned long last_map_addr = end;
354 int i = pud_index(addr);
356 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
357 unsigned long pmd_phys;
358 pud_t *pud = pud_page + pud_index(addr);
359 pmd_t *pmd;
361 if (addr >= end)
362 break;
364 if (!after_bootmem &&
365 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
366 set_pud(pud, __pud(0));
367 continue;
370 if (pud_val(*pud)) {
371 if (!pud_large(*pud))
372 last_map_addr = phys_pmd_update(pud, addr, end);
373 continue;
376 if (direct_gbpages) {
377 set_pte((pte_t *)pud,
378 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
379 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
380 continue;
383 pmd = alloc_low_page(&pmd_phys);
385 spin_lock(&init_mm.page_table_lock);
386 set_pud(pud, __pud(pmd_phys | _KERNPG_TABLE));
387 last_map_addr = phys_pmd_init(pmd, addr, end);
388 spin_unlock(&init_mm.page_table_lock);
390 unmap_low_page(pmd);
392 __flush_tlb_all();
394 return last_map_addr >> PAGE_SHIFT;
397 static void __init find_early_table_space(unsigned long end)
399 unsigned long puds, pmds, tables, start;
401 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
402 tables = round_up(puds * sizeof(pud_t), PAGE_SIZE);
403 if (!direct_gbpages) {
404 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
405 tables += round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
409 * RED-PEN putting page tables only on node 0 could
410 * cause a hotspot and fill up ZONE_DMA. The page tables
411 * need roughly 0.5KB per GB.
413 start = 0x8000;
414 table_start = find_e820_area(start, end, tables, PAGE_SIZE);
415 if (table_start == -1UL)
416 panic("Cannot find space for the kernel page tables");
418 table_start >>= PAGE_SHIFT;
419 table_end = table_start;
421 early_printk("kernel direct mapping tables up to %lx @ %lx-%lx\n",
422 end, table_start << PAGE_SHIFT,
423 (table_start << PAGE_SHIFT) + tables);
426 static void __init init_gbpages(void)
428 if (direct_gbpages && cpu_has_gbpages)
429 printk(KERN_INFO "Using GB pages for direct mapping\n");
430 else
431 direct_gbpages = 0;
434 #ifdef CONFIG_MEMTEST_BOOTPARAM
436 static void __init memtest(unsigned long start_phys, unsigned long size,
437 unsigned pattern)
439 unsigned long i;
440 unsigned long *start;
441 unsigned long start_bad;
442 unsigned long last_bad;
443 unsigned long val;
444 unsigned long start_phys_aligned;
445 unsigned long count;
446 unsigned long incr;
448 switch (pattern) {
449 case 0:
450 val = 0UL;
451 break;
452 case 1:
453 val = -1UL;
454 break;
455 case 2:
456 val = 0x5555555555555555UL;
457 break;
458 case 3:
459 val = 0xaaaaaaaaaaaaaaaaUL;
460 break;
461 default:
462 return;
465 incr = sizeof(unsigned long);
466 start_phys_aligned = ALIGN(start_phys, incr);
467 count = (size - (start_phys_aligned - start_phys))/incr;
468 start = __va(start_phys_aligned);
469 start_bad = 0;
470 last_bad = 0;
472 for (i = 0; i < count; i++)
473 start[i] = val;
474 for (i = 0; i < count; i++, start++, start_phys_aligned += incr) {
475 if (*start != val) {
476 if (start_phys_aligned == last_bad + incr) {
477 last_bad += incr;
478 } else {
479 if (start_bad) {
480 printk(KERN_CONT "\n %016lx bad mem addr %016lx - %016lx reserved",
481 val, start_bad, last_bad + incr);
482 reserve_early(start_bad, last_bad - start_bad, "BAD RAM");
484 start_bad = last_bad = start_phys_aligned;
488 if (start_bad) {
489 printk(KERN_CONT "\n %016lx bad mem addr %016lx - %016lx reserved",
490 val, start_bad, last_bad + incr);
491 reserve_early(start_bad, last_bad - start_bad, "BAD RAM");
496 static int memtest_pattern __initdata = CONFIG_MEMTEST_BOOTPARAM_VALUE;
498 static int __init parse_memtest(char *arg)
500 if (arg)
501 memtest_pattern = simple_strtoul(arg, NULL, 0);
502 return 0;
505 early_param("memtest", parse_memtest);
507 static void __init early_memtest(unsigned long start, unsigned long end)
509 u64 t_start, t_size;
510 unsigned pattern;
512 if (!memtest_pattern)
513 return;
515 printk(KERN_INFO "early_memtest: pattern num %d", memtest_pattern);
516 for (pattern = 0; pattern < memtest_pattern; pattern++) {
517 t_start = start;
518 t_size = 0;
519 while (t_start < end) {
520 t_start = find_e820_area_size(t_start, &t_size, 1);
522 /* done ? */
523 if (t_start >= end)
524 break;
525 if (t_start + t_size > end)
526 t_size = end - t_start;
528 printk(KERN_CONT "\n %016llx - %016llx pattern %d",
529 (unsigned long long)t_start,
530 (unsigned long long)t_start + t_size, pattern);
532 memtest(t_start, t_size, pattern);
534 t_start += t_size;
537 printk(KERN_CONT "\n");
539 #else
540 static void __init early_memtest(unsigned long start, unsigned long end)
543 #endif
546 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
547 * This runs before bootmem is initialized and gets pages directly from
548 * the physical memory. To access them they are temporarily mapped.
550 unsigned long __init_refok init_memory_mapping(unsigned long start, unsigned long end)
552 unsigned long next, last_map_addr = end;
553 unsigned long start_phys = start, end_phys = end;
555 printk(KERN_INFO "init_memory_mapping\n");
558 * Find space for the kernel direct mapping tables.
560 * Later we should allocate these tables in the local node of the
561 * memory mapped. Unfortunately this is done currently before the
562 * nodes are discovered.
564 if (!after_bootmem) {
565 init_gbpages();
566 find_early_table_space(end);
569 start = (unsigned long)__va(start);
570 end = (unsigned long)__va(end);
572 for (; start < end; start = next) {
573 pgd_t *pgd = pgd_offset_k(start);
574 unsigned long pud_phys;
575 pud_t *pud;
577 if (after_bootmem)
578 pud = pud_offset(pgd, start & PGDIR_MASK);
579 else
580 pud = alloc_low_page(&pud_phys);
582 next = start + PGDIR_SIZE;
583 if (next > end)
584 next = end;
585 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next));
586 if (!after_bootmem)
587 set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys));
588 unmap_low_page(pud);
591 if (!after_bootmem)
592 mmu_cr4_features = read_cr4();
593 __flush_tlb_all();
595 if (!after_bootmem)
596 reserve_early(table_start << PAGE_SHIFT,
597 table_end << PAGE_SHIFT, "PGTABLE");
599 if (!after_bootmem)
600 early_memtest(start_phys, end_phys);
602 return last_map_addr;
605 #ifndef CONFIG_NUMA
606 void __init paging_init(void)
608 unsigned long max_zone_pfns[MAX_NR_ZONES];
610 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
611 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
612 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
613 max_zone_pfns[ZONE_NORMAL] = end_pfn;
615 memory_present(0, 0, end_pfn);
616 sparse_init();
617 free_area_init_nodes(max_zone_pfns);
619 #endif
622 * Memory hotplug specific functions
624 #ifdef CONFIG_MEMORY_HOTPLUG
626 * Memory is added always to NORMAL zone. This means you will never get
627 * additional DMA/DMA32 memory.
629 int arch_add_memory(int nid, u64 start, u64 size)
631 struct pglist_data *pgdat = NODE_DATA(nid);
632 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
633 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
634 unsigned long nr_pages = size >> PAGE_SHIFT;
635 int ret;
637 last_mapped_pfn = init_memory_mapping(start, start + size-1);
638 if (last_mapped_pfn > max_pfn_mapped)
639 max_pfn_mapped = last_mapped_pfn;
641 ret = __add_pages(zone, start_pfn, nr_pages);
642 WARN_ON(1);
644 return ret;
646 EXPORT_SYMBOL_GPL(arch_add_memory);
648 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
649 int memory_add_physaddr_to_nid(u64 start)
651 return 0;
653 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
654 #endif
656 #endif /* CONFIG_MEMORY_HOTPLUG */
659 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
660 * is valid. The argument is a physical page number.
663 * On x86, access has to be given to the first megabyte of ram because that area
664 * contains bios code and data regions used by X and dosemu and similar apps.
665 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
666 * mmio resources as well as potential bios/acpi data regions.
668 int devmem_is_allowed(unsigned long pagenr)
670 if (pagenr <= 256)
671 return 1;
672 if (!page_is_ram(pagenr))
673 return 1;
674 return 0;
678 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
679 kcore_modules, kcore_vsyscall;
681 void __init mem_init(void)
683 long codesize, reservedpages, datasize, initsize;
685 pci_iommu_alloc();
687 /* clear_bss() already clear the empty_zero_page */
689 reservedpages = 0;
691 /* this will put all low memory onto the freelists */
692 #ifdef CONFIG_NUMA
693 totalram_pages = numa_free_all_bootmem();
694 #else
695 totalram_pages = free_all_bootmem();
696 #endif
697 reservedpages = end_pfn - totalram_pages -
698 absent_pages_in_range(0, end_pfn);
699 after_bootmem = 1;
701 codesize = (unsigned long) &_etext - (unsigned long) &_text;
702 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
703 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
705 /* Register memory areas for /proc/kcore */
706 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
707 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
708 VMALLOC_END-VMALLOC_START);
709 kclist_add(&kcore_kernel, &_stext, _end - _stext);
710 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
711 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
712 VSYSCALL_END - VSYSCALL_START);
714 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
715 "%ldk reserved, %ldk data, %ldk init)\n",
716 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
717 end_pfn << (PAGE_SHIFT-10),
718 codesize >> 10,
719 reservedpages << (PAGE_SHIFT-10),
720 datasize >> 10,
721 initsize >> 10);
723 cpa_init();
726 void free_init_pages(char *what, unsigned long begin, unsigned long end)
728 unsigned long addr = begin;
730 if (addr >= end)
731 return;
734 * If debugging page accesses then do not free this memory but
735 * mark them not present - any buggy init-section access will
736 * create a kernel page fault:
738 #ifdef CONFIG_DEBUG_PAGEALLOC
739 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
740 begin, PAGE_ALIGN(end));
741 set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
742 #else
743 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
745 for (; addr < end; addr += PAGE_SIZE) {
746 ClearPageReserved(virt_to_page(addr));
747 init_page_count(virt_to_page(addr));
748 memset((void *)(addr & ~(PAGE_SIZE-1)),
749 POISON_FREE_INITMEM, PAGE_SIZE);
750 free_page(addr);
751 totalram_pages++;
753 #endif
756 void free_initmem(void)
758 free_init_pages("unused kernel memory",
759 (unsigned long)(&__init_begin),
760 (unsigned long)(&__init_end));
763 #ifdef CONFIG_DEBUG_RODATA
764 const int rodata_test_data = 0xC3;
765 EXPORT_SYMBOL_GPL(rodata_test_data);
767 void mark_rodata_ro(void)
769 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
770 unsigned long rodata_start =
771 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
773 #ifdef CONFIG_DYNAMIC_FTRACE
774 /* Dynamic tracing modifies the kernel text section */
775 start = rodata_start;
776 #endif
778 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
779 (end - start) >> 10);
780 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
783 * The rodata section (but not the kernel text!) should also be
784 * not-executable.
786 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
788 rodata_test();
790 #ifdef CONFIG_CPA_DEBUG
791 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
792 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
794 printk(KERN_INFO "Testing CPA: again\n");
795 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
796 #endif
799 #endif
801 #ifdef CONFIG_BLK_DEV_INITRD
802 void free_initrd_mem(unsigned long start, unsigned long end)
804 free_init_pages("initrd memory", start, end);
806 #endif
808 void __init reserve_bootmem_generic(unsigned long phys, unsigned len)
810 #ifdef CONFIG_NUMA
811 int nid, next_nid;
812 #endif
813 unsigned long pfn = phys >> PAGE_SHIFT;
815 if (pfn >= end_pfn) {
817 * This can happen with kdump kernels when accessing
818 * firmware tables:
820 if (pfn < max_pfn_mapped)
821 return;
823 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %u\n",
824 phys, len);
825 return;
828 /* Should check here against the e820 map to avoid double free */
829 #ifdef CONFIG_NUMA
830 nid = phys_to_nid(phys);
831 next_nid = phys_to_nid(phys + len - 1);
832 if (nid == next_nid)
833 reserve_bootmem_node(NODE_DATA(nid), phys, len, BOOTMEM_DEFAULT);
834 else
835 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
836 #else
837 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
838 #endif
840 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
841 dma_reserve += len / PAGE_SIZE;
842 set_dma_reserve(dma_reserve);
846 int kern_addr_valid(unsigned long addr)
848 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
849 pgd_t *pgd;
850 pud_t *pud;
851 pmd_t *pmd;
852 pte_t *pte;
854 if (above != 0 && above != -1UL)
855 return 0;
857 pgd = pgd_offset_k(addr);
858 if (pgd_none(*pgd))
859 return 0;
861 pud = pud_offset(pgd, addr);
862 if (pud_none(*pud))
863 return 0;
865 pmd = pmd_offset(pud, addr);
866 if (pmd_none(*pmd))
867 return 0;
869 if (pmd_large(*pmd))
870 return pfn_valid(pmd_pfn(*pmd));
872 pte = pte_offset_kernel(pmd, addr);
873 if (pte_none(*pte))
874 return 0;
876 return pfn_valid(pte_pfn(*pte));
880 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
881 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
882 * not need special handling anymore:
884 static struct vm_area_struct gate_vma = {
885 .vm_start = VSYSCALL_START,
886 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
887 .vm_page_prot = PAGE_READONLY_EXEC,
888 .vm_flags = VM_READ | VM_EXEC
891 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
893 #ifdef CONFIG_IA32_EMULATION
894 if (test_tsk_thread_flag(tsk, TIF_IA32))
895 return NULL;
896 #endif
897 return &gate_vma;
900 int in_gate_area(struct task_struct *task, unsigned long addr)
902 struct vm_area_struct *vma = get_gate_vma(task);
904 if (!vma)
905 return 0;
907 return (addr >= vma->vm_start) && (addr < vma->vm_end);
911 * Use this when you have no reliable task/vma, typically from interrupt
912 * context. It is less reliable than using the task's vma and may give
913 * false positives:
915 int in_gate_area_no_task(unsigned long addr)
917 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
920 const char *arch_vma_name(struct vm_area_struct *vma)
922 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
923 return "[vdso]";
924 if (vma == &gate_vma)
925 return "[vsyscall]";
926 return NULL;
929 #ifdef CONFIG_SPARSEMEM_VMEMMAP
931 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
933 static long __meminitdata addr_start, addr_end;
934 static void __meminitdata *p_start, *p_end;
935 static int __meminitdata node_start;
937 int __meminit
938 vmemmap_populate(struct page *start_page, unsigned long size, int node)
940 unsigned long addr = (unsigned long)start_page;
941 unsigned long end = (unsigned long)(start_page + size);
942 unsigned long next;
943 pgd_t *pgd;
944 pud_t *pud;
945 pmd_t *pmd;
947 for (; addr < end; addr = next) {
948 next = pmd_addr_end(addr, end);
950 pgd = vmemmap_pgd_populate(addr, node);
951 if (!pgd)
952 return -ENOMEM;
954 pud = vmemmap_pud_populate(pgd, addr, node);
955 if (!pud)
956 return -ENOMEM;
958 pmd = pmd_offset(pud, addr);
959 if (pmd_none(*pmd)) {
960 pte_t entry;
961 void *p;
963 p = vmemmap_alloc_block(PMD_SIZE, node);
964 if (!p)
965 return -ENOMEM;
967 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
968 PAGE_KERNEL_LARGE);
969 set_pmd(pmd, __pmd(pte_val(entry)));
971 /* check to see if we have contiguous blocks */
972 if (p_end != p || node_start != node) {
973 if (p_start)
974 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
975 addr_start, addr_end-1, p_start, p_end-1, node_start);
976 addr_start = addr;
977 node_start = node;
978 p_start = p;
980 addr_end = addr + PMD_SIZE;
981 p_end = p + PMD_SIZE;
982 } else {
983 vmemmap_verify((pte_t *)pmd, node, addr, next);
986 return 0;
989 void __meminit vmemmap_populate_print_last(void)
991 if (p_start) {
992 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
993 addr_start, addr_end-1, p_start, p_end-1, node_start);
994 p_start = NULL;
995 p_end = NULL;
996 node_start = 0;
999 #endif