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>
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>
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/system.h>
35 #include <asm/uaccess.h>
36 #include <asm/pgtable.h>
37 #include <asm/pgalloc.h>
39 #include <asm/fixmap.h>
43 #include <asm/mmu_context.h>
44 #include <asm/proto.h>
46 #include <asm/sections.h>
47 #include <asm/kdebug.h>
49 #include <asm/cacheflush.h>
52 * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
53 * The direct mapping extends to max_pfn_mapped, so that we can directly access
54 * apertures, ACPI and other tables without having to play with fixmaps.
56 unsigned long max_low_pfn_mapped;
57 unsigned long max_pfn_mapped;
59 static unsigned long dma_reserve __initdata;
61 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
63 int direct_gbpages __meminitdata
64 #ifdef CONFIG_DIRECT_GBPAGES
69 static int __init parse_direct_gbpages_off(char *arg)
74 early_param("nogbpages", parse_direct_gbpages_off);
76 static int __init parse_direct_gbpages_on(char *arg)
81 early_param("gbpages", parse_direct_gbpages_on);
84 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
85 * physical space so we can cache the place of the first one and move
86 * around without checking the pgd every time.
91 static __init void *spp_getpage(void)
96 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
98 ptr = alloc_bootmem_pages(PAGE_SIZE);
100 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
101 panic("set_pte_phys: cannot allocate page data %s\n",
102 after_bootmem ? "after bootmem" : "");
105 pr_debug("spp_getpage %p\n", ptr);
111 set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
117 pud = pud_page + pud_index(vaddr);
118 if (pud_none(*pud)) {
119 pmd = (pmd_t *) spp_getpage();
120 pud_populate(&init_mm, pud, pmd);
121 if (pmd != pmd_offset(pud, 0)) {
122 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
123 pmd, pmd_offset(pud, 0));
127 pmd = pmd_offset(pud, vaddr);
128 if (pmd_none(*pmd)) {
129 pte = (pte_t *) spp_getpage();
130 pmd_populate_kernel(&init_mm, pmd, pte);
131 if (pte != pte_offset_kernel(pmd, 0)) {
132 printk(KERN_ERR "PAGETABLE BUG #02!\n");
137 pte = pte_offset_kernel(pmd, vaddr);
138 if (!pte_none(*pte) && pte_val(new_pte) &&
139 pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
141 set_pte(pte, new_pte);
144 * It's enough to flush this one mapping.
145 * (PGE mappings get flushed as well)
147 __flush_tlb_one(vaddr);
151 set_pte_vaddr(unsigned long vaddr, pte_t pteval)
156 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
158 pgd = pgd_offset_k(vaddr);
159 if (pgd_none(*pgd)) {
161 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
164 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
165 set_pte_vaddr_pud(pud_page, vaddr, pteval);
169 * Create large page table mappings for a range of physical addresses.
171 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
178 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
179 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
180 pgd = pgd_offset_k((unsigned long)__va(phys));
181 if (pgd_none(*pgd)) {
182 pud = (pud_t *) spp_getpage();
183 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
186 pud = pud_offset(pgd, (unsigned long)__va(phys));
187 if (pud_none(*pud)) {
188 pmd = (pmd_t *) spp_getpage();
189 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
192 pmd = pmd_offset(pud, phys);
193 BUG_ON(!pmd_none(*pmd));
194 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
198 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
200 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
203 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
205 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
209 * The head.S code sets up the kernel high mapping:
211 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
213 * phys_addr holds the negative offset to the kernel, which is added
214 * to the compile time generated pmds. This results in invalid pmds up
215 * to the point where we hit the physaddr 0 mapping.
217 * We limit the mappings to the region from _text to _end. _end is
218 * rounded up to the 2MB boundary. This catches the invalid pmds as
219 * well, as they are located before _text:
221 void __init cleanup_highmap(void)
223 unsigned long vaddr = __START_KERNEL_map;
224 unsigned long end = round_up((unsigned long)_end, PMD_SIZE) - 1;
225 pmd_t *pmd = level2_kernel_pgt;
226 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
228 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
231 if (vaddr < (unsigned long) _text || vaddr > end)
232 set_pmd(pmd, __pmd(0));
236 static unsigned long __initdata table_start;
237 static unsigned long __meminitdata table_end;
238 static unsigned long __meminitdata table_top;
240 static __meminit void *alloc_low_page(unsigned long *phys)
242 unsigned long pfn = table_end++;
246 adr = (void *)get_zeroed_page(GFP_ATOMIC);
252 if (pfn >= table_top)
253 panic("alloc_low_page: ran out of memory");
255 adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
256 memset(adr, 0, PAGE_SIZE);
257 *phys = pfn * PAGE_SIZE;
261 static __meminit void unmap_low_page(void *adr)
266 early_iounmap(adr, PAGE_SIZE);
269 static unsigned long __meminit
270 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end)
273 unsigned long last_map_addr = end;
276 pte_t *pte = pte_page + pte_index(addr);
278 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
281 if (!after_bootmem) {
282 for(; i < PTRS_PER_PTE; i++, pte++)
283 set_pte(pte, __pte(0));
292 printk(" pte=%p addr=%lx pte=%016lx\n",
293 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
294 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL));
295 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
298 update_page_count(PG_LEVEL_4K, pages);
300 return last_map_addr;
303 static unsigned long __meminit
304 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end)
306 pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
308 return phys_pte_init(pte, address, end);
311 static unsigned long __meminit
312 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
313 unsigned long page_size_mask)
315 unsigned long pages = 0;
316 unsigned long last_map_addr = end;
318 int i = pmd_index(address);
320 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
321 unsigned long pte_phys;
322 pmd_t *pmd = pmd_page + pmd_index(address);
325 if (address >= end) {
326 if (!after_bootmem) {
327 for (; i < PTRS_PER_PMD; i++, pmd++)
328 set_pmd(pmd, __pmd(0));
334 if (!pmd_large(*pmd))
335 last_map_addr = phys_pte_update(pmd, address,
340 if (page_size_mask & (1<<PG_LEVEL_2M)) {
342 set_pte((pte_t *)pmd,
343 pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
344 last_map_addr = (address & PMD_MASK) + PMD_SIZE;
348 pte = alloc_low_page(&pte_phys);
349 last_map_addr = phys_pte_init(pte, address, end);
352 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
354 update_page_count(PG_LEVEL_2M, pages);
355 return last_map_addr;
358 static unsigned long __meminit
359 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
360 unsigned long page_size_mask)
362 pmd_t *pmd = pmd_offset(pud, 0);
363 unsigned long last_map_addr;
365 spin_lock(&init_mm.page_table_lock);
366 last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask);
367 spin_unlock(&init_mm.page_table_lock);
369 return last_map_addr;
372 static unsigned long __meminit
373 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
374 unsigned long page_size_mask)
376 unsigned long pages = 0;
377 unsigned long last_map_addr = end;
378 int i = pud_index(addr);
380 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
381 unsigned long pmd_phys;
382 pud_t *pud = pud_page + pud_index(addr);
388 if (!after_bootmem &&
389 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
390 set_pud(pud, __pud(0));
395 if (!pud_large(*pud))
396 last_map_addr = phys_pmd_update(pud, addr, end,
401 if (page_size_mask & (1<<PG_LEVEL_1G)) {
403 set_pte((pte_t *)pud,
404 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
405 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
409 pmd = alloc_low_page(&pmd_phys);
411 spin_lock(&init_mm.page_table_lock);
412 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask);
414 pud_populate(&init_mm, pud, __va(pmd_phys));
415 spin_unlock(&init_mm.page_table_lock);
419 update_page_count(PG_LEVEL_1G, pages);
421 return last_map_addr;
424 static unsigned long __meminit
425 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
426 unsigned long page_size_mask)
430 pud = (pud_t *)pgd_page_vaddr(*pgd);
432 return phys_pud_init(pud, addr, end, page_size_mask);
435 static void __init find_early_table_space(unsigned long end)
437 unsigned long puds, pmds, ptes, tables, start;
439 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
440 tables = round_up(puds * sizeof(pud_t), PAGE_SIZE);
441 if (direct_gbpages) {
443 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
444 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
446 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
447 tables += round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
451 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
452 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
454 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
455 tables += round_up(ptes * sizeof(pte_t), PAGE_SIZE);
458 * RED-PEN putting page tables only on node 0 could
459 * cause a hotspot and fill up ZONE_DMA. The page tables
460 * need roughly 0.5KB per GB.
463 table_start = find_e820_area(start, end, tables, PAGE_SIZE);
464 if (table_start == -1UL)
465 panic("Cannot find space for the kernel page tables");
467 table_start >>= PAGE_SHIFT;
468 table_end = table_start;
469 table_top = table_start + (tables >> PAGE_SHIFT);
471 printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
472 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
475 static void __init init_gbpages(void)
477 if (direct_gbpages && cpu_has_gbpages)
478 printk(KERN_INFO "Using GB pages for direct mapping\n");
483 static unsigned long __init kernel_physical_mapping_init(unsigned long start,
485 unsigned long page_size_mask)
488 unsigned long next, last_map_addr = end;
490 start = (unsigned long)__va(start);
491 end = (unsigned long)__va(end);
493 for (; start < end; start = next) {
494 pgd_t *pgd = pgd_offset_k(start);
495 unsigned long pud_phys;
498 next = (start + PGDIR_SIZE) & PGDIR_MASK;
503 last_map_addr = phys_pud_update(pgd, __pa(start),
504 __pa(end), page_size_mask);
509 pud = pud_offset(pgd, start & PGDIR_MASK);
511 pud = alloc_low_page(&pud_phys);
513 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
516 pgd_populate(&init_mm, pgd_offset_k(start),
520 return last_map_addr;
526 unsigned page_size_mask;
529 #define NR_RANGE_MR 5
531 static int save_mr(struct map_range *mr, int nr_range,
532 unsigned long start_pfn, unsigned long end_pfn,
533 unsigned long page_size_mask)
536 if (start_pfn < end_pfn) {
537 if (nr_range >= NR_RANGE_MR)
538 panic("run out of range for init_memory_mapping\n");
539 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
540 mr[nr_range].end = end_pfn<<PAGE_SHIFT;
541 mr[nr_range].page_size_mask = page_size_mask;
549 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
550 * This runs before bootmem is initialized and gets pages directly from
551 * the physical memory. To access them they are temporarily mapped.
553 unsigned long __init_refok init_memory_mapping(unsigned long start,
556 unsigned long last_map_addr = 0;
557 unsigned long page_size_mask = 0;
558 unsigned long start_pfn, end_pfn;
560 struct map_range mr[NR_RANGE_MR];
563 printk(KERN_INFO "init_memory_mapping\n");
566 * Find space for the kernel direct mapping tables.
568 * Later we should allocate these tables in the local node of the
569 * memory mapped. Unfortunately this is done currently before the
570 * nodes are discovered.
576 page_size_mask |= 1 << PG_LEVEL_1G;
578 page_size_mask |= 1 << PG_LEVEL_2M;
580 memset(mr, 0, sizeof(mr));
583 /* head if not big page alignment ?*/
584 start_pfn = start >> PAGE_SHIFT;
585 end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
586 << (PMD_SHIFT - PAGE_SHIFT);
587 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
589 /* big page (2M) range*/
590 start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
591 << (PMD_SHIFT - PAGE_SHIFT);
592 end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT)
593 << (PUD_SHIFT - PAGE_SHIFT);
594 if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
595 end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
596 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
597 page_size_mask & (1<<PG_LEVEL_2M));
599 /* big page (1G) range */
601 end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
602 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
604 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
606 /* tail is not big page (1G) alignment */
608 end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
609 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
610 page_size_mask & (1<<PG_LEVEL_2M));
612 /* tail is not big page (2M) alignment */
614 end_pfn = end>>PAGE_SHIFT;
615 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
617 /* try to merge same page size and continuous */
618 for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
619 unsigned long old_start;
620 if (mr[i].end != mr[i+1].start ||
621 mr[i].page_size_mask != mr[i+1].page_size_mask)
624 old_start = mr[i].start;
625 memmove(&mr[i], &mr[i+1],
626 (nr_range - 1 - i) * sizeof (struct map_range));
627 mr[i].start = old_start;
631 for (i = 0; i < nr_range; i++)
632 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
633 mr[i].start, mr[i].end,
634 (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
635 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
638 find_early_table_space(end);
640 for (i = 0; i < nr_range; i++)
641 last_map_addr = kernel_physical_mapping_init(
642 mr[i].start, mr[i].end,
643 mr[i].page_size_mask);
646 mmu_cr4_features = read_cr4();
649 if (!after_bootmem && table_end > table_start)
650 reserve_early(table_start << PAGE_SHIFT,
651 table_end << PAGE_SHIFT, "PGTABLE");
653 printk(KERN_INFO "last_map_addr: %lx end: %lx\n",
657 early_memtest(start, end);
659 return last_map_addr >> PAGE_SHIFT;
663 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
665 unsigned long bootmap_size, bootmap;
667 bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
668 bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
671 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
672 /* don't touch min_low_pfn */
673 bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
675 e820_register_active_regions(0, start_pfn, end_pfn);
676 free_bootmem_with_active_regions(0, end_pfn);
677 early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
678 reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
681 void __init paging_init(void)
683 unsigned long max_zone_pfns[MAX_NR_ZONES];
685 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
686 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
687 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
688 max_zone_pfns[ZONE_NORMAL] = max_pfn;
690 memory_present(0, 0, max_pfn);
692 free_area_init_nodes(max_zone_pfns);
697 * Memory hotplug specific functions
699 #ifdef CONFIG_MEMORY_HOTPLUG
701 * Memory is added always to NORMAL zone. This means you will never get
702 * additional DMA/DMA32 memory.
704 int arch_add_memory(int nid, u64 start, u64 size)
706 struct pglist_data *pgdat = NODE_DATA(nid);
707 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
708 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
709 unsigned long nr_pages = size >> PAGE_SHIFT;
712 last_mapped_pfn = init_memory_mapping(start, start + size-1);
713 if (last_mapped_pfn > max_pfn_mapped)
714 max_pfn_mapped = last_mapped_pfn;
716 ret = __add_pages(zone, start_pfn, nr_pages);
721 EXPORT_SYMBOL_GPL(arch_add_memory);
723 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
724 int memory_add_physaddr_to_nid(u64 start)
728 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
731 #endif /* CONFIG_MEMORY_HOTPLUG */
734 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
735 * is valid. The argument is a physical page number.
738 * On x86, access has to be given to the first megabyte of ram because that area
739 * contains bios code and data regions used by X and dosemu and similar apps.
740 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
741 * mmio resources as well as potential bios/acpi data regions.
743 int devmem_is_allowed(unsigned long pagenr)
747 if (!page_is_ram(pagenr))
753 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
754 kcore_modules, kcore_vsyscall;
756 void __init mem_init(void)
758 long codesize, reservedpages, datasize, initsize;
762 /* clear_bss() already clear the empty_zero_page */
766 /* this will put all low memory onto the freelists */
768 totalram_pages = numa_free_all_bootmem();
770 totalram_pages = free_all_bootmem();
772 reservedpages = max_pfn - totalram_pages -
773 absent_pages_in_range(0, max_pfn);
776 codesize = (unsigned long) &_etext - (unsigned long) &_text;
777 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
778 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
780 /* Register memory areas for /proc/kcore */
781 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
782 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
783 VMALLOC_END-VMALLOC_START);
784 kclist_add(&kcore_kernel, &_stext, _end - _stext);
785 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
786 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
787 VSYSCALL_END - VSYSCALL_START);
789 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
790 "%ldk reserved, %ldk data, %ldk init)\n",
791 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
792 max_pfn << (PAGE_SHIFT-10),
794 reservedpages << (PAGE_SHIFT-10),
801 void free_init_pages(char *what, unsigned long begin, unsigned long end)
803 unsigned long addr = begin;
809 * If debugging page accesses then do not free this memory but
810 * mark them not present - any buggy init-section access will
811 * create a kernel page fault:
813 #ifdef CONFIG_DEBUG_PAGEALLOC
814 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
815 begin, PAGE_ALIGN(end));
816 set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
818 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
820 for (; addr < end; addr += PAGE_SIZE) {
821 ClearPageReserved(virt_to_page(addr));
822 init_page_count(virt_to_page(addr));
823 memset((void *)(addr & ~(PAGE_SIZE-1)),
824 POISON_FREE_INITMEM, PAGE_SIZE);
831 void free_initmem(void)
833 free_init_pages("unused kernel memory",
834 (unsigned long)(&__init_begin),
835 (unsigned long)(&__init_end));
838 #ifdef CONFIG_DEBUG_RODATA
839 const int rodata_test_data = 0xC3;
840 EXPORT_SYMBOL_GPL(rodata_test_data);
842 void mark_rodata_ro(void)
844 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
845 unsigned long rodata_start =
846 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
848 #ifdef CONFIG_DYNAMIC_FTRACE
849 /* Dynamic tracing modifies the kernel text section */
850 start = rodata_start;
853 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
854 (end - start) >> 10);
855 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
858 * The rodata section (but not the kernel text!) should also be
861 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
865 #ifdef CONFIG_CPA_DEBUG
866 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
867 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
869 printk(KERN_INFO "Testing CPA: again\n");
870 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
876 #ifdef CONFIG_BLK_DEV_INITRD
877 void free_initrd_mem(unsigned long start, unsigned long end)
879 free_init_pages("initrd memory", start, end);
883 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
890 unsigned long pfn = phys >> PAGE_SHIFT;
892 if (pfn >= max_pfn) {
894 * This can happen with kdump kernels when accessing
897 if (pfn < max_pfn_mapped)
900 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
905 /* Should check here against the e820 map to avoid double free */
907 nid = phys_to_nid(phys);
908 next_nid = phys_to_nid(phys + len - 1);
910 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
912 ret = reserve_bootmem(phys, len, flags);
918 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
921 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
922 dma_reserve += len / PAGE_SIZE;
923 set_dma_reserve(dma_reserve);
929 int kern_addr_valid(unsigned long addr)
931 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
937 if (above != 0 && above != -1UL)
940 pgd = pgd_offset_k(addr);
944 pud = pud_offset(pgd, addr);
948 pmd = pmd_offset(pud, addr);
953 return pfn_valid(pmd_pfn(*pmd));
955 pte = pte_offset_kernel(pmd, addr);
959 return pfn_valid(pte_pfn(*pte));
963 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
964 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
965 * not need special handling anymore:
967 static struct vm_area_struct gate_vma = {
968 .vm_start = VSYSCALL_START,
969 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
970 .vm_page_prot = PAGE_READONLY_EXEC,
971 .vm_flags = VM_READ | VM_EXEC
974 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
976 #ifdef CONFIG_IA32_EMULATION
977 if (test_tsk_thread_flag(tsk, TIF_IA32))
983 int in_gate_area(struct task_struct *task, unsigned long addr)
985 struct vm_area_struct *vma = get_gate_vma(task);
990 return (addr >= vma->vm_start) && (addr < vma->vm_end);
994 * Use this when you have no reliable task/vma, typically from interrupt
995 * context. It is less reliable than using the task's vma and may give
998 int in_gate_area_no_task(unsigned long addr)
1000 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1003 const char *arch_vma_name(struct vm_area_struct *vma)
1005 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1007 if (vma == &gate_vma)
1008 return "[vsyscall]";
1012 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1014 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1016 static long __meminitdata addr_start, addr_end;
1017 static void __meminitdata *p_start, *p_end;
1018 static int __meminitdata node_start;
1021 vmemmap_populate(struct page *start_page, unsigned long size, int node)
1023 unsigned long addr = (unsigned long)start_page;
1024 unsigned long end = (unsigned long)(start_page + size);
1030 for (; addr < end; addr = next) {
1033 pgd = vmemmap_pgd_populate(addr, node);
1037 pud = vmemmap_pud_populate(pgd, addr, node);
1042 next = (addr + PAGE_SIZE) & PAGE_MASK;
1043 pmd = vmemmap_pmd_populate(pud, addr, node);
1048 p = vmemmap_pte_populate(pmd, addr, node);
1053 addr_end = addr + PAGE_SIZE;
1054 p_end = p + PAGE_SIZE;
1056 next = pmd_addr_end(addr, end);
1058 pmd = pmd_offset(pud, addr);
1059 if (pmd_none(*pmd)) {
1062 p = vmemmap_alloc_block(PMD_SIZE, node);
1066 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1068 set_pmd(pmd, __pmd(pte_val(entry)));
1070 /* check to see if we have contiguous blocks */
1071 if (p_end != p || node_start != node) {
1073 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1074 addr_start, addr_end-1, p_start, p_end-1, node_start);
1080 addr_end = addr + PMD_SIZE;
1081 p_end = p + PMD_SIZE;
1083 vmemmap_verify((pte_t *)pmd, node, addr, next);
1090 void __meminit vmemmap_populate_print_last(void)
1093 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1094 addr_start, addr_end-1, p_start, p_end-1, node_start);