x86: account overlapped mappings in max_pfn_mapped
[linux-2.6/mini2440.git] / arch / x86 / mm / init_64.c
blob1076097dcab22115f5de1e9b22afc1baf2129ab6
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 const struct dma_mapping_ops *dma_ops;
51 EXPORT_SYMBOL(dma_ops);
53 static unsigned long dma_reserve __initdata;
55 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
57 int direct_gbpages __meminitdata
58 #ifdef CONFIG_DIRECT_GBPAGES
59 = 1
60 #endif
63 static int __init parse_direct_gbpages_off(char *arg)
65 direct_gbpages = 0;
66 return 0;
68 early_param("nogbpages", parse_direct_gbpages_off);
70 static int __init parse_direct_gbpages_on(char *arg)
72 direct_gbpages = 1;
73 return 0;
75 early_param("gbpages", parse_direct_gbpages_on);
78 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
79 * physical space so we can cache the place of the first one and move
80 * around without checking the pgd every time.
83 void show_mem(void)
85 long i, total = 0, reserved = 0;
86 long shared = 0, cached = 0;
87 struct page *page;
88 pg_data_t *pgdat;
90 printk(KERN_INFO "Mem-info:\n");
91 show_free_areas();
92 for_each_online_pgdat(pgdat) {
93 for (i = 0; i < pgdat->node_spanned_pages; ++i) {
95 * This loop can take a while with 256 GB and
96 * 4k pages so defer the NMI watchdog:
98 if (unlikely(i % MAX_ORDER_NR_PAGES == 0))
99 touch_nmi_watchdog();
101 if (!pfn_valid(pgdat->node_start_pfn + i))
102 continue;
104 page = pfn_to_page(pgdat->node_start_pfn + i);
105 total++;
106 if (PageReserved(page))
107 reserved++;
108 else if (PageSwapCache(page))
109 cached++;
110 else if (page_count(page))
111 shared += page_count(page) - 1;
114 printk(KERN_INFO "%lu pages of RAM\n", total);
115 printk(KERN_INFO "%lu reserved pages\n", reserved);
116 printk(KERN_INFO "%lu pages shared\n", shared);
117 printk(KERN_INFO "%lu pages swap cached\n", cached);
120 int after_bootmem;
122 static __init void *spp_getpage(void)
124 void *ptr;
126 if (after_bootmem)
127 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
128 else
129 ptr = alloc_bootmem_pages(PAGE_SIZE);
131 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
132 panic("set_pte_phys: cannot allocate page data %s\n",
133 after_bootmem ? "after bootmem" : "");
136 pr_debug("spp_getpage %p\n", ptr);
138 return ptr;
141 static __init void
142 set_pte_phys(unsigned long vaddr, unsigned long phys, pgprot_t prot)
144 pgd_t *pgd;
145 pud_t *pud;
146 pmd_t *pmd;
147 pte_t *pte, new_pte;
149 pr_debug("set_pte_phys %lx to %lx\n", vaddr, phys);
151 pgd = pgd_offset_k(vaddr);
152 if (pgd_none(*pgd)) {
153 printk(KERN_ERR
154 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
155 return;
157 pud = pud_offset(pgd, vaddr);
158 if (pud_none(*pud)) {
159 pmd = (pmd_t *) spp_getpage();
160 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | _PAGE_USER));
161 if (pmd != pmd_offset(pud, 0)) {
162 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
163 pmd, pmd_offset(pud, 0));
164 return;
167 pmd = pmd_offset(pud, vaddr);
168 if (pmd_none(*pmd)) {
169 pte = (pte_t *) spp_getpage();
170 set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER));
171 if (pte != pte_offset_kernel(pmd, 0)) {
172 printk(KERN_ERR "PAGETABLE BUG #02!\n");
173 return;
176 new_pte = pfn_pte(phys >> PAGE_SHIFT, prot);
178 pte = pte_offset_kernel(pmd, vaddr);
179 if (!pte_none(*pte) &&
180 pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
181 pte_ERROR(*pte);
182 set_pte(pte, new_pte);
185 * It's enough to flush this one mapping.
186 * (PGE mappings get flushed as well)
188 __flush_tlb_one(vaddr);
192 * The head.S code sets up the kernel high mapping:
194 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
196 * phys_addr holds the negative offset to the kernel, which is added
197 * to the compile time generated pmds. This results in invalid pmds up
198 * to the point where we hit the physaddr 0 mapping.
200 * We limit the mappings to the region from _text to _end. _end is
201 * rounded up to the 2MB boundary. This catches the invalid pmds as
202 * well, as they are located before _text:
204 void __init cleanup_highmap(void)
206 unsigned long vaddr = __START_KERNEL_map;
207 unsigned long end = round_up((unsigned long)_end, PMD_SIZE) - 1;
208 pmd_t *pmd = level2_kernel_pgt;
209 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
211 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
212 if (!pmd_present(*pmd))
213 continue;
214 if (vaddr < (unsigned long) _text || vaddr > end)
215 set_pmd(pmd, __pmd(0));
219 /* NOTE: this is meant to be run only at boot */
220 void __init
221 __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
223 unsigned long address = __fix_to_virt(idx);
225 if (idx >= __end_of_fixed_addresses) {
226 printk(KERN_ERR "Invalid __set_fixmap\n");
227 return;
229 set_pte_phys(address, phys, prot);
232 static unsigned long __initdata table_start;
233 static unsigned long __meminitdata table_end;
235 static __meminit void *alloc_low_page(unsigned long *phys)
237 unsigned long pfn = table_end++;
238 void *adr;
240 if (after_bootmem) {
241 adr = (void *)get_zeroed_page(GFP_ATOMIC);
242 *phys = __pa(adr);
244 return adr;
247 if (pfn >= end_pfn)
248 panic("alloc_low_page: ran out of memory");
250 adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
251 memset(adr, 0, PAGE_SIZE);
252 *phys = pfn * PAGE_SIZE;
253 return adr;
256 static __meminit void unmap_low_page(void *adr)
258 if (after_bootmem)
259 return;
261 early_iounmap(adr, PAGE_SIZE);
264 /* Must run before zap_low_mappings */
265 __meminit void *early_ioremap(unsigned long addr, unsigned long size)
267 pmd_t *pmd, *last_pmd;
268 unsigned long vaddr;
269 int i, pmds;
271 pmds = ((addr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
272 vaddr = __START_KERNEL_map;
273 pmd = level2_kernel_pgt;
274 last_pmd = level2_kernel_pgt + PTRS_PER_PMD - 1;
276 for (; pmd <= last_pmd; pmd++, vaddr += PMD_SIZE) {
277 for (i = 0; i < pmds; i++) {
278 if (pmd_present(pmd[i]))
279 goto continue_outer_loop;
281 vaddr += addr & ~PMD_MASK;
282 addr &= PMD_MASK;
284 for (i = 0; i < pmds; i++, addr += PMD_SIZE)
285 set_pmd(pmd+i, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
286 __flush_tlb_all();
288 return (void *)vaddr;
289 continue_outer_loop:
292 printk(KERN_ERR "early_ioremap(0x%lx, %lu) failed\n", addr, size);
294 return NULL;
298 * To avoid virtual aliases later:
300 __meminit void early_iounmap(void *addr, unsigned long size)
302 unsigned long vaddr;
303 pmd_t *pmd;
304 int i, pmds;
306 vaddr = (unsigned long)addr;
307 pmds = ((vaddr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
308 pmd = level2_kernel_pgt + pmd_index(vaddr);
310 for (i = 0; i < pmds; i++)
311 pmd_clear(pmd + i);
313 __flush_tlb_all();
316 static unsigned long __meminit
317 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end)
319 int i = pmd_index(address);
321 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
322 pmd_t *pmd = pmd_page + pmd_index(address);
324 if (address >= end) {
325 if (!after_bootmem) {
326 for (; i < PTRS_PER_PMD; i++, pmd++)
327 set_pmd(pmd, __pmd(0));
329 break;
332 if (pmd_val(*pmd))
333 continue;
335 set_pte((pte_t *)pmd,
336 pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
338 return address;
341 static unsigned long __meminit
342 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end)
344 pmd_t *pmd = pmd_offset(pud, 0);
345 unsigned long last_map_addr;
347 spin_lock(&init_mm.page_table_lock);
348 last_map_addr = phys_pmd_init(pmd, address, end);
349 spin_unlock(&init_mm.page_table_lock);
350 __flush_tlb_all();
351 return last_map_addr;
354 static unsigned long __meminit
355 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end)
357 unsigned long last_map_addr = end;
358 int i = pud_index(addr);
360 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
361 unsigned long pmd_phys;
362 pud_t *pud = pud_page + pud_index(addr);
363 pmd_t *pmd;
365 if (addr >= end)
366 break;
368 if (!after_bootmem &&
369 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
370 set_pud(pud, __pud(0));
371 continue;
374 if (pud_val(*pud)) {
375 if (!pud_large(*pud))
376 last_map_addr = phys_pmd_update(pud, addr, end);
377 continue;
380 if (direct_gbpages) {
381 set_pte((pte_t *)pud,
382 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
383 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
384 continue;
387 pmd = alloc_low_page(&pmd_phys);
389 spin_lock(&init_mm.page_table_lock);
390 set_pud(pud, __pud(pmd_phys | _KERNPG_TABLE));
391 last_map_addr = phys_pmd_init(pmd, addr, end);
392 spin_unlock(&init_mm.page_table_lock);
394 unmap_low_page(pmd);
396 __flush_tlb_all();
398 return last_map_addr >> PAGE_SHIFT;
401 static void __init find_early_table_space(unsigned long end)
403 unsigned long puds, pmds, tables, start;
405 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
406 tables = round_up(puds * sizeof(pud_t), PAGE_SIZE);
407 if (!direct_gbpages) {
408 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
409 tables += round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
413 * RED-PEN putting page tables only on node 0 could
414 * cause a hotspot and fill up ZONE_DMA. The page tables
415 * need roughly 0.5KB per GB.
417 start = 0x8000;
418 table_start = find_e820_area(start, end, tables, PAGE_SIZE);
419 if (table_start == -1UL)
420 panic("Cannot find space for the kernel page tables");
422 table_start >>= PAGE_SHIFT;
423 table_end = table_start;
425 early_printk("kernel direct mapping tables up to %lx @ %lx-%lx\n",
426 end, table_start << PAGE_SHIFT,
427 (table_start << PAGE_SHIFT) + tables);
430 static void __init init_gbpages(void)
432 if (direct_gbpages && cpu_has_gbpages)
433 printk(KERN_INFO "Using GB pages for direct mapping\n");
434 else
435 direct_gbpages = 0;
438 #ifdef CONFIG_MEMTEST_BOOTPARAM
440 static void __init memtest(unsigned long start_phys, unsigned long size,
441 unsigned pattern)
443 unsigned long i;
444 unsigned long *start;
445 unsigned long start_bad;
446 unsigned long last_bad;
447 unsigned long val;
448 unsigned long start_phys_aligned;
449 unsigned long count;
450 unsigned long incr;
452 switch (pattern) {
453 case 0:
454 val = 0UL;
455 break;
456 case 1:
457 val = -1UL;
458 break;
459 case 2:
460 val = 0x5555555555555555UL;
461 break;
462 case 3:
463 val = 0xaaaaaaaaaaaaaaaaUL;
464 break;
465 default:
466 return;
469 incr = sizeof(unsigned long);
470 start_phys_aligned = ALIGN(start_phys, incr);
471 count = (size - (start_phys_aligned - start_phys))/incr;
472 start = __va(start_phys_aligned);
473 start_bad = 0;
474 last_bad = 0;
476 for (i = 0; i < count; i++)
477 start[i] = val;
478 for (i = 0; i < count; i++, start++, start_phys_aligned += incr) {
479 if (*start != val) {
480 if (start_phys_aligned == last_bad + incr) {
481 last_bad += incr;
482 } else {
483 if (start_bad) {
484 printk(KERN_CONT "\n %016lx bad mem addr %016lx - %016lx reserved",
485 val, start_bad, last_bad + incr);
486 reserve_early(start_bad, last_bad - start_bad, "BAD RAM");
488 start_bad = last_bad = start_phys_aligned;
492 if (start_bad) {
493 printk(KERN_CONT "\n %016lx bad mem addr %016lx - %016lx reserved",
494 val, start_bad, last_bad + incr);
495 reserve_early(start_bad, last_bad - start_bad, "BAD RAM");
500 static int memtest_pattern __initdata = CONFIG_MEMTEST_BOOTPARAM_VALUE;
502 static int __init parse_memtest(char *arg)
504 if (arg)
505 memtest_pattern = simple_strtoul(arg, NULL, 0);
506 return 0;
509 early_param("memtest", parse_memtest);
511 static void __init early_memtest(unsigned long start, unsigned long end)
513 unsigned long t_start, t_size;
514 unsigned pattern;
516 if (!memtest_pattern)
517 return;
519 printk(KERN_INFO "early_memtest: pattern num %d", memtest_pattern);
520 for (pattern = 0; pattern < memtest_pattern; pattern++) {
521 t_start = start;
522 t_size = 0;
523 while (t_start < end) {
524 t_start = find_e820_area_size(t_start, &t_size, 1);
526 /* done ? */
527 if (t_start >= end)
528 break;
529 if (t_start + t_size > end)
530 t_size = end - t_start;
532 printk(KERN_CONT "\n %016lx - %016lx pattern %d",
533 t_start, t_start + t_size, pattern);
535 memtest(t_start, t_size, pattern);
537 t_start += t_size;
540 printk(KERN_CONT "\n");
542 #else
543 static void __init early_memtest(unsigned long start, unsigned long end)
546 #endif
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, unsigned long end)
555 unsigned long next, last_map_addr = end;
556 unsigned long start_phys = start, end_phys = end;
558 printk(KERN_INFO "init_memory_mapping\n");
561 * Find space for the kernel direct mapping tables.
563 * Later we should allocate these tables in the local node of the
564 * memory mapped. Unfortunately this is done currently before the
565 * nodes are discovered.
567 if (!after_bootmem) {
568 init_gbpages();
569 find_early_table_space(end);
572 start = (unsigned long)__va(start);
573 end = (unsigned long)__va(end);
575 for (; start < end; start = next) {
576 pgd_t *pgd = pgd_offset_k(start);
577 unsigned long pud_phys;
578 pud_t *pud;
580 if (after_bootmem)
581 pud = pud_offset(pgd, start & PGDIR_MASK);
582 else
583 pud = alloc_low_page(&pud_phys);
585 next = start + PGDIR_SIZE;
586 if (next > end)
587 next = end;
588 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next));
589 if (!after_bootmem)
590 set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys));
591 unmap_low_page(pud);
594 if (!after_bootmem)
595 mmu_cr4_features = read_cr4();
596 __flush_tlb_all();
598 if (!after_bootmem)
599 reserve_early(table_start << PAGE_SHIFT,
600 table_end << PAGE_SHIFT, "PGTABLE");
602 if (!after_bootmem)
603 early_memtest(start_phys, end_phys);
605 return last_map_addr;
608 #ifndef CONFIG_NUMA
609 void __init paging_init(void)
611 unsigned long max_zone_pfns[MAX_NR_ZONES];
613 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
614 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
615 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
616 max_zone_pfns[ZONE_NORMAL] = end_pfn;
618 memory_present(0, 0, end_pfn);
619 sparse_init();
620 free_area_init_nodes(max_zone_pfns);
622 #endif
625 * Memory hotplug specific functions
627 void online_page(struct page *page)
629 ClearPageReserved(page);
630 init_page_count(page);
631 __free_page(page);
632 totalram_pages++;
633 num_physpages++;
636 #ifdef CONFIG_MEMORY_HOTPLUG
638 * Memory is added always to NORMAL zone. This means you will never get
639 * additional DMA/DMA32 memory.
641 int arch_add_memory(int nid, u64 start, u64 size)
643 struct pglist_data *pgdat = NODE_DATA(nid);
644 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
645 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
646 unsigned long nr_pages = size >> PAGE_SHIFT;
647 int ret;
649 last_mapped_pfn = init_memory_mapping(start, start + size-1);
650 if (last_mapped_pfn > max_pfn_mapped)
651 max_pfn_mapped = last_mapped_pfn;
653 ret = __add_pages(zone, start_pfn, nr_pages);
654 WARN_ON(1);
656 return ret;
658 EXPORT_SYMBOL_GPL(arch_add_memory);
660 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
661 int memory_add_physaddr_to_nid(u64 start)
663 return 0;
665 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
666 #endif
668 #endif /* CONFIG_MEMORY_HOTPLUG */
670 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
671 kcore_modules, kcore_vsyscall;
673 void __init mem_init(void)
675 long codesize, reservedpages, datasize, initsize;
677 pci_iommu_alloc();
679 /* clear_bss() already clear the empty_zero_page */
681 reservedpages = 0;
683 /* this will put all low memory onto the freelists */
684 #ifdef CONFIG_NUMA
685 totalram_pages = numa_free_all_bootmem();
686 #else
687 totalram_pages = free_all_bootmem();
688 #endif
689 reservedpages = end_pfn - totalram_pages -
690 absent_pages_in_range(0, end_pfn);
691 after_bootmem = 1;
693 codesize = (unsigned long) &_etext - (unsigned long) &_text;
694 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
695 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
697 /* Register memory areas for /proc/kcore */
698 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
699 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
700 VMALLOC_END-VMALLOC_START);
701 kclist_add(&kcore_kernel, &_stext, _end - _stext);
702 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
703 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
704 VSYSCALL_END - VSYSCALL_START);
706 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
707 "%ldk reserved, %ldk data, %ldk init)\n",
708 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
709 end_pfn << (PAGE_SHIFT-10),
710 codesize >> 10,
711 reservedpages << (PAGE_SHIFT-10),
712 datasize >> 10,
713 initsize >> 10);
715 cpa_init();
718 void free_init_pages(char *what, unsigned long begin, unsigned long end)
720 unsigned long addr = begin;
722 if (addr >= end)
723 return;
726 * If debugging page accesses then do not free this memory but
727 * mark them not present - any buggy init-section access will
728 * create a kernel page fault:
730 #ifdef CONFIG_DEBUG_PAGEALLOC
731 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
732 begin, PAGE_ALIGN(end));
733 set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
734 #else
735 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
737 for (; addr < end; addr += PAGE_SIZE) {
738 ClearPageReserved(virt_to_page(addr));
739 init_page_count(virt_to_page(addr));
740 memset((void *)(addr & ~(PAGE_SIZE-1)),
741 POISON_FREE_INITMEM, PAGE_SIZE);
742 free_page(addr);
743 totalram_pages++;
745 #endif
748 void free_initmem(void)
750 free_init_pages("unused kernel memory",
751 (unsigned long)(&__init_begin),
752 (unsigned long)(&__init_end));
755 #ifdef CONFIG_DEBUG_RODATA
756 const int rodata_test_data = 0xC3;
757 EXPORT_SYMBOL_GPL(rodata_test_data);
759 void mark_rodata_ro(void)
761 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
763 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
764 (end - start) >> 10);
765 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
768 * The rodata section (but not the kernel text!) should also be
769 * not-executable.
771 start = ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
772 set_memory_nx(start, (end - start) >> PAGE_SHIFT);
774 rodata_test();
776 #ifdef CONFIG_CPA_DEBUG
777 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
778 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
780 printk(KERN_INFO "Testing CPA: again\n");
781 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
782 #endif
785 #endif
787 #ifdef CONFIG_BLK_DEV_INITRD
788 void free_initrd_mem(unsigned long start, unsigned long end)
790 free_init_pages("initrd memory", start, end);
792 #endif
794 void __init reserve_bootmem_generic(unsigned long phys, unsigned len)
796 #ifdef CONFIG_NUMA
797 int nid = phys_to_nid(phys);
798 #endif
799 unsigned long pfn = phys >> PAGE_SHIFT;
801 if (pfn >= end_pfn) {
803 * This can happen with kdump kernels when accessing
804 * firmware tables:
806 if (pfn < max_pfn_mapped)
807 return;
809 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %u\n",
810 phys, len);
811 return;
814 /* Should check here against the e820 map to avoid double free */
815 #ifdef CONFIG_NUMA
816 reserve_bootmem_node(NODE_DATA(nid), phys, len, BOOTMEM_DEFAULT);
817 #else
818 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
819 #endif
820 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
821 dma_reserve += len / PAGE_SIZE;
822 set_dma_reserve(dma_reserve);
826 int kern_addr_valid(unsigned long addr)
828 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
829 pgd_t *pgd;
830 pud_t *pud;
831 pmd_t *pmd;
832 pte_t *pte;
834 if (above != 0 && above != -1UL)
835 return 0;
837 pgd = pgd_offset_k(addr);
838 if (pgd_none(*pgd))
839 return 0;
841 pud = pud_offset(pgd, addr);
842 if (pud_none(*pud))
843 return 0;
845 pmd = pmd_offset(pud, addr);
846 if (pmd_none(*pmd))
847 return 0;
849 if (pmd_large(*pmd))
850 return pfn_valid(pmd_pfn(*pmd));
852 pte = pte_offset_kernel(pmd, addr);
853 if (pte_none(*pte))
854 return 0;
856 return pfn_valid(pte_pfn(*pte));
860 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
861 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
862 * not need special handling anymore:
864 static struct vm_area_struct gate_vma = {
865 .vm_start = VSYSCALL_START,
866 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
867 .vm_page_prot = PAGE_READONLY_EXEC,
868 .vm_flags = VM_READ | VM_EXEC
871 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
873 #ifdef CONFIG_IA32_EMULATION
874 if (test_tsk_thread_flag(tsk, TIF_IA32))
875 return NULL;
876 #endif
877 return &gate_vma;
880 int in_gate_area(struct task_struct *task, unsigned long addr)
882 struct vm_area_struct *vma = get_gate_vma(task);
884 if (!vma)
885 return 0;
887 return (addr >= vma->vm_start) && (addr < vma->vm_end);
891 * Use this when you have no reliable task/vma, typically from interrupt
892 * context. It is less reliable than using the task's vma and may give
893 * false positives:
895 int in_gate_area_no_task(unsigned long addr)
897 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
900 const char *arch_vma_name(struct vm_area_struct *vma)
902 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
903 return "[vdso]";
904 if (vma == &gate_vma)
905 return "[vsyscall]";
906 return NULL;
909 #ifdef CONFIG_SPARSEMEM_VMEMMAP
911 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
913 int __meminit
914 vmemmap_populate(struct page *start_page, unsigned long size, int node)
916 unsigned long addr = (unsigned long)start_page;
917 unsigned long end = (unsigned long)(start_page + size);
918 unsigned long next;
919 pgd_t *pgd;
920 pud_t *pud;
921 pmd_t *pmd;
923 for (; addr < end; addr = next) {
924 next = pmd_addr_end(addr, end);
926 pgd = vmemmap_pgd_populate(addr, node);
927 if (!pgd)
928 return -ENOMEM;
930 pud = vmemmap_pud_populate(pgd, addr, node);
931 if (!pud)
932 return -ENOMEM;
934 pmd = pmd_offset(pud, addr);
935 if (pmd_none(*pmd)) {
936 pte_t entry;
937 void *p;
939 p = vmemmap_alloc_block(PMD_SIZE, node);
940 if (!p)
941 return -ENOMEM;
943 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
944 PAGE_KERNEL_LARGE);
945 set_pmd(pmd, __pmd(pte_val(entry)));
947 printk(KERN_DEBUG " [%lx-%lx] PMD ->%p on node %d\n",
948 addr, addr + PMD_SIZE - 1, p, node);
949 } else {
950 vmemmap_verify((pte_t *)pmd, node, addr, next);
953 return 0;
955 #endif