1 /* 2 * linux/arch/x86_64/mm/init.c 3 * 4 * Copyright (C) 1995 Linus Torvalds 5 * Copyright (C) 2000 Pavel Machek <pavel@suse.cz> 6 * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de> 7 */ 8 9 #include <linux/signal.h> 10 #include <linux/sched.h> 11 #include <linux/kernel.h> 12 #include <linux/errno.h> 13 #include <linux/string.h> 14 #include <linux/types.h> 15 #include <linux/ptrace.h> 16 #include <linux/mman.h> 17 #include <linux/mm.h> 18 #include <linux/swap.h> 19 #include <linux/smp.h> 20 #include <linux/init.h> 21 #include <linux/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> 31 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> 49 50 static unsigned long dma_reserve __initdata; 51 52 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 53 54 int direct_gbpages __meminitdata 55 #ifdef CONFIG_DIRECT_GBPAGES 56 = 1 57 #endif 58 ; 59 60 static int __init parse_direct_gbpages_off(char *arg) 61 { 62 direct_gbpages = 0; 63 return 0; 64 } 65 early_param("nogbpages", parse_direct_gbpages_off); 66 67 static int __init parse_direct_gbpages_on(char *arg) 68 { 69 direct_gbpages = 1; 70 return 0; 71 } 72 early_param("gbpages", parse_direct_gbpages_on); 73 74 /* 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. 78 */ 79 80 void show_mem(void) 81 { 82 long i, total = 0, reserved = 0; 83 long shared = 0, cached = 0; 84 struct page *page; 85 pg_data_t *pgdat; 86 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) { 91 /* 92 * This loop can take a while with 256 GB and 93 * 4k pages so defer the NMI watchdog: 94 */ 95 if (unlikely(i % MAX_ORDER_NR_PAGES == 0)) 96 touch_nmi_watchdog(); 97 98 if (!pfn_valid(pgdat->node_start_pfn + i)) 99 continue; 100 101 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; 109 } 110 } 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); 115 } 116 117 int after_bootmem; 118 119 static __init void *spp_getpage(void) 120 { 121 void *ptr; 122 123 if (after_bootmem) 124 ptr = (void *) get_zeroed_page(GFP_ATOMIC); 125 else 126 ptr = alloc_bootmem_pages(PAGE_SIZE); 127 128 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) { 129 panic("set_pte_phys: cannot allocate page data %s\n", 130 after_bootmem ? "after bootmem" : ""); 131 } 132 133 pr_debug("spp_getpage %p\n", ptr); 134 135 return ptr; 136 } 137 138 static void 139 set_pte_phys(unsigned long vaddr, unsigned long phys, pgprot_t prot) 140 { 141 pgd_t *pgd; 142 pud_t *pud; 143 pmd_t *pmd; 144 pte_t *pte, new_pte; 145 146 pr_debug("set_pte_phys %lx to %lx\n", vaddr, phys); 147 148 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; 153 } 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; 162 } 163 } 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; 171 } 172 } 173 new_pte = pfn_pte(phys >> PAGE_SHIFT, prot); 174 175 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); 180 181 /* 182 * It's enough to flush this one mapping. 183 * (PGE mappings get flushed as well) 184 */ 185 __flush_tlb_one(vaddr); 186 } 187 188 /* 189 * The head.S code sets up the kernel high mapping: 190 * 191 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text) 192 * 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. 196 * 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: 200 */ 201 void __init cleanup_highmap(void) 202 { 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; 207 208 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) { 209 if (!pmd_present(*pmd)) 210 continue; 211 if (vaddr < (unsigned long) _text || vaddr > end) 212 set_pmd(pmd, __pmd(0)); 213 } 214 } 215 216 /* NOTE: this is meant to be run only at boot */ 217 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot) 218 { 219 unsigned long address = __fix_to_virt(idx); 220 221 if (idx >= __end_of_fixed_addresses) { 222 printk(KERN_ERR "Invalid __set_fixmap\n"); 223 return; 224 } 225 set_pte_phys(address, phys, prot); 226 } 227 228 static unsigned long __initdata table_start; 229 static unsigned long __meminitdata table_end; 230 231 static __meminit void *alloc_low_page(unsigned long *phys) 232 { 233 unsigned long pfn = table_end++; 234 void *adr; 235 236 if (after_bootmem) { 237 adr = (void *)get_zeroed_page(GFP_ATOMIC); 238 *phys = __pa(adr); 239 240 return adr; 241 } 242 243 if (pfn >= end_pfn) 244 panic("alloc_low_page: ran out of memory"); 245 246 adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE); 247 memset(adr, 0, PAGE_SIZE); 248 *phys = pfn * PAGE_SIZE; 249 return adr; 250 } 251 252 static __meminit void unmap_low_page(void *adr) 253 { 254 if (after_bootmem) 255 return; 256 257 early_iounmap(adr, PAGE_SIZE); 258 } 259 260 /* Must run before zap_low_mappings */ 261 __meminit void *early_ioremap(unsigned long addr, unsigned long size) 262 { 263 pmd_t *pmd, *last_pmd; 264 unsigned long vaddr; 265 int i, pmds; 266 267 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; 271 272 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; 276 } 277 vaddr += addr & ~PMD_MASK; 278 addr &= PMD_MASK; 279 280 for (i = 0; i < pmds; i++, addr += PMD_SIZE) 281 set_pmd(pmd+i, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC)); 282 __flush_tlb_all(); 283 284 return (void *)vaddr; 285 continue_outer_loop: 286 ; 287 } 288 printk(KERN_ERR "early_ioremap(0x%lx, %lu) failed\n", addr, size); 289 290 return NULL; 291 } 292 293 /* 294 * To avoid virtual aliases later: 295 */ 296 __meminit void early_iounmap(void *addr, unsigned long size) 297 { 298 unsigned long vaddr; 299 pmd_t *pmd; 300 int i, pmds; 301 302 vaddr = (unsigned long)addr; 303 pmds = ((vaddr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE; 304 pmd = level2_kernel_pgt + pmd_index(vaddr); 305 306 for (i = 0; i < pmds; i++) 307 pmd_clear(pmd + i); 308 309 __flush_tlb_all(); 310 } 311 312 static unsigned long __meminit 313 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end) 314 { 315 int i = pmd_index(address); 316 317 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) { 318 pmd_t *pmd = pmd_page + pmd_index(address); 319 320 if (address >= end) { 321 if (!after_bootmem) { 322 for (; i < PTRS_PER_PMD; i++, pmd++) 323 set_pmd(pmd, __pmd(0)); 324 } 325 break; 326 } 327 328 if (pmd_val(*pmd)) 329 continue; 330 331 set_pte((pte_t *)pmd, 332 pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE)); 333 } 334 return address; 335 } 336 337 static unsigned long __meminit 338 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end) 339 { 340 pmd_t *pmd = pmd_offset(pud, 0); 341 unsigned long last_map_addr; 342 343 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; 348 } 349 350 static unsigned long __meminit 351 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end) 352 { 353 unsigned long last_map_addr = end; 354 int i = pud_index(addr); 355 356 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; 360 361 if (addr >= end) 362 break; 363 364 if (!after_bootmem && 365 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) { 366 set_pud(pud, __pud(0)); 367 continue; 368 } 369 370 if (pud_val(*pud)) { 371 if (!pud_large(*pud)) 372 last_map_addr = phys_pmd_update(pud, addr, end); 373 continue; 374 } 375 376 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; 381 } 382 383 pmd = alloc_low_page(&pmd_phys); 384 385 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); 389 390 unmap_low_page(pmd); 391 } 392 __flush_tlb_all(); 393 394 return last_map_addr >> PAGE_SHIFT; 395 } 396 397 static void __init find_early_table_space(unsigned long end) 398 { 399 unsigned long puds, pmds, tables, start; 400 401 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); 406 } 407 408 /* 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. 412 */ 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"); 417 418 table_start >>= PAGE_SHIFT; 419 table_end = table_start; 420 421 early_printk("kernel direct mapping tables up to %lx @ %lx-%lx\n", 422 end, table_start << PAGE_SHIFT, 423 (table_start << PAGE_SHIFT) + tables); 424 } 425 426 static void __init init_gbpages(void) 427 { 428 if (direct_gbpages && cpu_has_gbpages) 429 printk(KERN_INFO "Using GB pages for direct mapping\n"); 430 else 431 direct_gbpages = 0; 432 } 433 434 #ifdef CONFIG_MEMTEST_BOOTPARAM 435 436 static void __init memtest(unsigned long start_phys, unsigned long size, 437 unsigned pattern) 438 { 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; 447 448 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; 463 } 464 465 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; 471 472 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"); 483 } 484 start_bad = last_bad = start_phys_aligned; 485 } 486 } 487 } 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"); 492 } 493 494 } 495 496 static int memtest_pattern __initdata = CONFIG_MEMTEST_BOOTPARAM_VALUE; 497 498 static int __init parse_memtest(char *arg) 499 { 500 if (arg) 501 memtest_pattern = simple_strtoul(arg, NULL, 0); 502 return 0; 503 } 504 505 early_param("memtest", parse_memtest); 506 507 static void __init early_memtest(unsigned long start, unsigned long end) 508 { 509 unsigned long t_start, t_size; 510 unsigned pattern; 511 512 if (!memtest_pattern) 513 return; 514 515 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); 521 522 /* done ? */ 523 if (t_start >= end) 524 break; 525 if (t_start + t_size > end) 526 t_size = end - t_start; 527 528 printk(KERN_CONT "\n %016lx - %016lx pattern %d", 529 t_start, t_start + t_size, pattern); 530 531 memtest(t_start, t_size, pattern); 532 533 t_start += t_size; 534 } 535 } 536 printk(KERN_CONT "\n"); 537 } 538 #else 539 static void __init early_memtest(unsigned long start, unsigned long end) 540 { 541 } 542 #endif 543 544 /* 545 * Setup the direct mapping of the physical memory at PAGE_OFFSET. 546 * This runs before bootmem is initialized and gets pages directly from 547 * the physical memory. To access them they are temporarily mapped. 548 */ 549 unsigned long __init_refok init_memory_mapping(unsigned long start, unsigned long end) 550 { 551 unsigned long next, last_map_addr = end; 552 unsigned long start_phys = start, end_phys = end; 553 554 printk(KERN_INFO "init_memory_mapping\n"); 555 556 /* 557 * Find space for the kernel direct mapping tables. 558 * 559 * Later we should allocate these tables in the local node of the 560 * memory mapped. Unfortunately this is done currently before the 561 * nodes are discovered. 562 */ 563 if (!after_bootmem) { 564 init_gbpages(); 565 find_early_table_space(end); 566 } 567 568 start = (unsigned long)__va(start); 569 end = (unsigned long)__va(end); 570 571 for (; start < end; start = next) { 572 pgd_t *pgd = pgd_offset_k(start); 573 unsigned long pud_phys; 574 pud_t *pud; 575 576 if (after_bootmem) 577 pud = pud_offset(pgd, start & PGDIR_MASK); 578 else 579 pud = alloc_low_page(&pud_phys); 580 581 next = start + PGDIR_SIZE; 582 if (next > end) 583 next = end; 584 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next)); 585 if (!after_bootmem) 586 set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys)); 587 unmap_low_page(pud); 588 } 589 590 if (!after_bootmem) 591 mmu_cr4_features = read_cr4(); 592 __flush_tlb_all(); 593 594 if (!after_bootmem) 595 reserve_early(table_start << PAGE_SHIFT, 596 table_end << PAGE_SHIFT, "PGTABLE"); 597 598 if (!after_bootmem) 599 early_memtest(start_phys, end_phys); 600 601 return last_map_addr; 602 } 603 604 #ifndef CONFIG_NUMA 605 void __init paging_init(void) 606 { 607 unsigned long max_zone_pfns[MAX_NR_ZONES]; 608 609 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 610 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 611 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 612 max_zone_pfns[ZONE_NORMAL] = end_pfn; 613 614 memory_present(0, 0, end_pfn); 615 sparse_init(); 616 free_area_init_nodes(max_zone_pfns); 617 } 618 #endif 619 620 /* 621 * Memory hotplug specific functions 622 */ 623 #ifdef CONFIG_MEMORY_HOTPLUG 624 /* 625 * Memory is added always to NORMAL zone. This means you will never get 626 * additional DMA/DMA32 memory. 627 */ 628 int arch_add_memory(int nid, u64 start, u64 size) 629 { 630 struct pglist_data *pgdat = NODE_DATA(nid); 631 struct zone *zone = pgdat->node_zones + ZONE_NORMAL; 632 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT; 633 unsigned long nr_pages = size >> PAGE_SHIFT; 634 int ret; 635 636 last_mapped_pfn = init_memory_mapping(start, start + size-1); 637 if (last_mapped_pfn > max_pfn_mapped) 638 max_pfn_mapped = last_mapped_pfn; 639 640 ret = __add_pages(zone, start_pfn, nr_pages); 641 WARN_ON(1); 642 643 return ret; 644 } 645 EXPORT_SYMBOL_GPL(arch_add_memory); 646 647 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA) 648 int memory_add_physaddr_to_nid(u64 start) 649 { 650 return 0; 651 } 652 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); 653 #endif 654 655 #endif /* CONFIG_MEMORY_HOTPLUG */ 656 657 /* 658 * devmem_is_allowed() checks to see if /dev/mem access to a certain address 659 * is valid. The argument is a physical page number. 660 * 661 * 662 * On x86, access has to be given to the first megabyte of ram because that area 663 * contains bios code and data regions used by X and dosemu and similar apps. 664 * Access has to be given to non-kernel-ram areas as well, these contain the PCI 665 * mmio resources as well as potential bios/acpi data regions. 666 */ 667 int devmem_is_allowed(unsigned long pagenr) 668 { 669 if (pagenr <= 256) 670 return 1; 671 if (!page_is_ram(pagenr)) 672 return 1; 673 return 0; 674 } 675 676 677 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel, 678 kcore_modules, kcore_vsyscall; 679 680 void __init mem_init(void) 681 { 682 long codesize, reservedpages, datasize, initsize; 683 684 pci_iommu_alloc(); 685 686 /* clear_bss() already clear the empty_zero_page */ 687 688 reservedpages = 0; 689 690 /* this will put all low memory onto the freelists */ 691 #ifdef CONFIG_NUMA 692 totalram_pages = numa_free_all_bootmem(); 693 #else 694 totalram_pages = free_all_bootmem(); 695 #endif 696 reservedpages = end_pfn - totalram_pages - 697 absent_pages_in_range(0, end_pfn); 698 after_bootmem = 1; 699 700 codesize = (unsigned long) &_etext - (unsigned long) &_text; 701 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 702 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 703 704 /* Register memory areas for /proc/kcore */ 705 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); 706 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, 707 VMALLOC_END-VMALLOC_START); 708 kclist_add(&kcore_kernel, &_stext, _end - _stext); 709 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN); 710 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START, 711 VSYSCALL_END - VSYSCALL_START); 712 713 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 714 "%ldk reserved, %ldk data, %ldk init)\n", 715 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 716 end_pfn << (PAGE_SHIFT-10), 717 codesize >> 10, 718 reservedpages << (PAGE_SHIFT-10), 719 datasize >> 10, 720 initsize >> 10); 721 722 cpa_init(); 723 } 724 725 void free_init_pages(char *what, unsigned long begin, unsigned long end) 726 { 727 unsigned long addr = begin; 728 729 if (addr >= end) 730 return; 731 732 /* 733 * If debugging page accesses then do not free this memory but 734 * mark them not present - any buggy init-section access will 735 * create a kernel page fault: 736 */ 737 #ifdef CONFIG_DEBUG_PAGEALLOC 738 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", 739 begin, PAGE_ALIGN(end)); 740 set_memory_np(begin, (end - begin) >> PAGE_SHIFT); 741 #else 742 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); 743 744 for (; addr < end; addr += PAGE_SIZE) { 745 ClearPageReserved(virt_to_page(addr)); 746 init_page_count(virt_to_page(addr)); 747 memset((void *)(addr & ~(PAGE_SIZE-1)), 748 POISON_FREE_INITMEM, PAGE_SIZE); 749 free_page(addr); 750 totalram_pages++; 751 } 752 #endif 753 } 754 755 void free_initmem(void) 756 { 757 free_init_pages("unused kernel memory", 758 (unsigned long)(&__init_begin), 759 (unsigned long)(&__init_end)); 760 } 761 762 #ifdef CONFIG_DEBUG_RODATA 763 const int rodata_test_data = 0xC3; 764 EXPORT_SYMBOL_GPL(rodata_test_data); 765 766 void mark_rodata_ro(void) 767 { 768 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata); 769 770 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", 771 (end - start) >> 10); 772 set_memory_ro(start, (end - start) >> PAGE_SHIFT); 773 774 /* 775 * The rodata section (but not the kernel text!) should also be 776 * not-executable. 777 */ 778 start = ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK; 779 set_memory_nx(start, (end - start) >> PAGE_SHIFT); 780 781 rodata_test(); 782 783 #ifdef CONFIG_CPA_DEBUG 784 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end); 785 set_memory_rw(start, (end-start) >> PAGE_SHIFT); 786 787 printk(KERN_INFO "Testing CPA: again\n"); 788 set_memory_ro(start, (end-start) >> PAGE_SHIFT); 789 #endif 790 } 791 792 #endif 793 794 #ifdef CONFIG_BLK_DEV_INITRD 795 void free_initrd_mem(unsigned long start, unsigned long end) 796 { 797 free_init_pages("initrd memory", start, end); 798 } 799 #endif 800 801 void __init reserve_bootmem_generic(unsigned long phys, unsigned len) 802 { 803 #ifdef CONFIG_NUMA 804 int nid, next_nid; 805 #endif 806 unsigned long pfn = phys >> PAGE_SHIFT; 807 808 if (pfn >= end_pfn) { 809 /* 810 * This can happen with kdump kernels when accessing 811 * firmware tables: 812 */ 813 if (pfn < max_pfn_mapped) 814 return; 815 816 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %u\n", 817 phys, len); 818 return; 819 } 820 821 /* Should check here against the e820 map to avoid double free */ 822 #ifdef CONFIG_NUMA 823 nid = phys_to_nid(phys); 824 next_nid = phys_to_nid(phys + len - 1); 825 if (nid == next_nid) 826 reserve_bootmem_node(NODE_DATA(nid), phys, len, BOOTMEM_DEFAULT); 827 else 828 reserve_bootmem(phys, len, BOOTMEM_DEFAULT); 829 #else 830 reserve_bootmem(phys, len, BOOTMEM_DEFAULT); 831 #endif 832 833 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) { 834 dma_reserve += len / PAGE_SIZE; 835 set_dma_reserve(dma_reserve); 836 } 837 } 838 839 int kern_addr_valid(unsigned long addr) 840 { 841 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT; 842 pgd_t *pgd; 843 pud_t *pud; 844 pmd_t *pmd; 845 pte_t *pte; 846 847 if (above != 0 && above != -1UL) 848 return 0; 849 850 pgd = pgd_offset_k(addr); 851 if (pgd_none(*pgd)) 852 return 0; 853 854 pud = pud_offset(pgd, addr); 855 if (pud_none(*pud)) 856 return 0; 857 858 pmd = pmd_offset(pud, addr); 859 if (pmd_none(*pmd)) 860 return 0; 861 862 if (pmd_large(*pmd)) 863 return pfn_valid(pmd_pfn(*pmd)); 864 865 pte = pte_offset_kernel(pmd, addr); 866 if (pte_none(*pte)) 867 return 0; 868 869 return pfn_valid(pte_pfn(*pte)); 870 } 871 872 /* 873 * A pseudo VMA to allow ptrace access for the vsyscall page. This only 874 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does 875 * not need special handling anymore: 876 */ 877 static struct vm_area_struct gate_vma = { 878 .vm_start = VSYSCALL_START, 879 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE), 880 .vm_page_prot = PAGE_READONLY_EXEC, 881 .vm_flags = VM_READ | VM_EXEC 882 }; 883 884 struct vm_area_struct *get_gate_vma(struct task_struct *tsk) 885 { 886 #ifdef CONFIG_IA32_EMULATION 887 if (test_tsk_thread_flag(tsk, TIF_IA32)) 888 return NULL; 889 #endif 890 return &gate_vma; 891 } 892 893 int in_gate_area(struct task_struct *task, unsigned long addr) 894 { 895 struct vm_area_struct *vma = get_gate_vma(task); 896 897 if (!vma) 898 return 0; 899 900 return (addr >= vma->vm_start) && (addr < vma->vm_end); 901 } 902 903 /* 904 * Use this when you have no reliable task/vma, typically from interrupt 905 * context. It is less reliable than using the task's vma and may give 906 * false positives: 907 */ 908 int in_gate_area_no_task(unsigned long addr) 909 { 910 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END); 911 } 912 913 const char *arch_vma_name(struct vm_area_struct *vma) 914 { 915 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) 916 return "[vdso]"; 917 if (vma == &gate_vma) 918 return "[vsyscall]"; 919 return NULL; 920 } 921 922 #ifdef CONFIG_SPARSEMEM_VMEMMAP 923 /* 924 * Initialise the sparsemem vmemmap using huge-pages at the PMD level. 925 */ 926 static long __meminitdata addr_start, addr_end; 927 static void __meminitdata *p_start, *p_end; 928 static int __meminitdata node_start; 929 930 int __meminit 931 vmemmap_populate(struct page *start_page, unsigned long size, int node) 932 { 933 unsigned long addr = (unsigned long)start_page; 934 unsigned long end = (unsigned long)(start_page + size); 935 unsigned long next; 936 pgd_t *pgd; 937 pud_t *pud; 938 pmd_t *pmd; 939 940 for (; addr < end; addr = next) { 941 next = pmd_addr_end(addr, end); 942 943 pgd = vmemmap_pgd_populate(addr, node); 944 if (!pgd) 945 return -ENOMEM; 946 947 pud = vmemmap_pud_populate(pgd, addr, node); 948 if (!pud) 949 return -ENOMEM; 950 951 pmd = pmd_offset(pud, addr); 952 if (pmd_none(*pmd)) { 953 pte_t entry; 954 void *p; 955 956 p = vmemmap_alloc_block(PMD_SIZE, node); 957 if (!p) 958 return -ENOMEM; 959 960 entry = pfn_pte(__pa(p) >> PAGE_SHIFT, 961 PAGE_KERNEL_LARGE); 962 set_pmd(pmd, __pmd(pte_val(entry))); 963 964 /* check to see if we have contiguous blocks */ 965 if (p_end != p || node_start != node) { 966 if (p_start) 967 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n", 968 addr_start, addr_end-1, p_start, p_end-1, node_start); 969 addr_start = addr; 970 node_start = node; 971 p_start = p; 972 } 973 addr_end = addr + PMD_SIZE; 974 p_end = p + PMD_SIZE; 975 } else { 976 vmemmap_verify((pte_t *)pmd, node, addr, next); 977 } 978 } 979 return 0; 980 } 981 982 void __meminit vmemmap_populate_print_last(void) 983 { 984 if (p_start) { 985 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n", 986 addr_start, addr_end-1, p_start, p_end-1, node_start); 987 p_start = NULL; 988 p_end = NULL; 989 node_start = 0; 990 } 991 } 992 #endif 993