init_64.c revision cae5d39032acf26c265f6b1dc73d7ce6ff4bc387
1/* 2 * linux/arch/x86_64/mm/init.c 3 * 4 * Copyright (C) 1995 Linus Torvalds 5 * Copyright (C) 2000 Pavel Machek <pavel@ucw.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/initrd.h> 22#include <linux/pagemap.h> 23#include <linux/bootmem.h> 24#include <linux/memblock.h> 25#include <linux/proc_fs.h> 26#include <linux/pci.h> 27#include <linux/pfn.h> 28#include <linux/poison.h> 29#include <linux/dma-mapping.h> 30#include <linux/module.h> 31#include <linux/memory_hotplug.h> 32#include <linux/nmi.h> 33#include <linux/gfp.h> 34 35#include <asm/processor.h> 36#include <asm/bios_ebda.h> 37#include <asm/system.h> 38#include <asm/uaccess.h> 39#include <asm/pgtable.h> 40#include <asm/pgalloc.h> 41#include <asm/dma.h> 42#include <asm/fixmap.h> 43#include <asm/e820.h> 44#include <asm/apic.h> 45#include <asm/tlb.h> 46#include <asm/mmu_context.h> 47#include <asm/proto.h> 48#include <asm/smp.h> 49#include <asm/sections.h> 50#include <asm/kdebug.h> 51#include <asm/numa.h> 52#include <asm/cacheflush.h> 53#include <asm/init.h> 54#include <asm/uv/uv.h> 55 56static int __init parse_direct_gbpages_off(char *arg) 57{ 58 direct_gbpages = 0; 59 return 0; 60} 61early_param("nogbpages", parse_direct_gbpages_off); 62 63static int __init parse_direct_gbpages_on(char *arg) 64{ 65 direct_gbpages = 1; 66 return 0; 67} 68early_param("gbpages", parse_direct_gbpages_on); 69 70/* 71 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the 72 * physical space so we can cache the place of the first one and move 73 * around without checking the pgd every time. 74 */ 75 76pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP; 77EXPORT_SYMBOL_GPL(__supported_pte_mask); 78 79int force_personality32; 80 81/* 82 * noexec32=on|off 83 * Control non executable heap for 32bit processes. 84 * To control the stack too use noexec=off 85 * 86 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default) 87 * off PROT_READ implies PROT_EXEC 88 */ 89static int __init nonx32_setup(char *str) 90{ 91 if (!strcmp(str, "on")) 92 force_personality32 &= ~READ_IMPLIES_EXEC; 93 else if (!strcmp(str, "off")) 94 force_personality32 |= READ_IMPLIES_EXEC; 95 return 1; 96} 97__setup("noexec32=", nonx32_setup); 98 99/* 100 * When memory was added/removed make sure all the processes MM have 101 * suitable PGD entries in the local PGD level page. 102 */ 103void sync_global_pgds(unsigned long start, unsigned long end) 104{ 105 unsigned long address; 106 107 for (address = start; address <= end; address += PGDIR_SIZE) { 108 const pgd_t *pgd_ref = pgd_offset_k(address); 109 struct page *page; 110 111 if (pgd_none(*pgd_ref)) 112 continue; 113 114 spin_lock(&pgd_lock); 115 list_for_each_entry(page, &pgd_list, lru) { 116 pgd_t *pgd; 117 spinlock_t *pgt_lock; 118 119 pgd = (pgd_t *)page_address(page) + pgd_index(address); 120 /* the pgt_lock only for Xen */ 121 pgt_lock = &pgd_page_get_mm(page)->page_table_lock; 122 spin_lock(pgt_lock); 123 124 if (pgd_none(*pgd)) 125 set_pgd(pgd, *pgd_ref); 126 else 127 BUG_ON(pgd_page_vaddr(*pgd) 128 != pgd_page_vaddr(*pgd_ref)); 129 130 spin_unlock(pgt_lock); 131 } 132 spin_unlock(&pgd_lock); 133 } 134} 135 136/* 137 * NOTE: This function is marked __ref because it calls __init function 138 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0. 139 */ 140static __ref void *spp_getpage(void) 141{ 142 void *ptr; 143 144 if (after_bootmem) 145 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK); 146 else 147 ptr = alloc_bootmem_pages(PAGE_SIZE); 148 149 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) { 150 panic("set_pte_phys: cannot allocate page data %s\n", 151 after_bootmem ? "after bootmem" : ""); 152 } 153 154 pr_debug("spp_getpage %p\n", ptr); 155 156 return ptr; 157} 158 159static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr) 160{ 161 if (pgd_none(*pgd)) { 162 pud_t *pud = (pud_t *)spp_getpage(); 163 pgd_populate(&init_mm, pgd, pud); 164 if (pud != pud_offset(pgd, 0)) 165 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n", 166 pud, pud_offset(pgd, 0)); 167 } 168 return pud_offset(pgd, vaddr); 169} 170 171static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr) 172{ 173 if (pud_none(*pud)) { 174 pmd_t *pmd = (pmd_t *) spp_getpage(); 175 pud_populate(&init_mm, pud, pmd); 176 if (pmd != pmd_offset(pud, 0)) 177 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n", 178 pmd, pmd_offset(pud, 0)); 179 } 180 return pmd_offset(pud, vaddr); 181} 182 183static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr) 184{ 185 if (pmd_none(*pmd)) { 186 pte_t *pte = (pte_t *) spp_getpage(); 187 pmd_populate_kernel(&init_mm, pmd, pte); 188 if (pte != pte_offset_kernel(pmd, 0)) 189 printk(KERN_ERR "PAGETABLE BUG #02!\n"); 190 } 191 return pte_offset_kernel(pmd, vaddr); 192} 193 194void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte) 195{ 196 pud_t *pud; 197 pmd_t *pmd; 198 pte_t *pte; 199 200 pud = pud_page + pud_index(vaddr); 201 pmd = fill_pmd(pud, vaddr); 202 pte = fill_pte(pmd, vaddr); 203 204 set_pte(pte, new_pte); 205 206 /* 207 * It's enough to flush this one mapping. 208 * (PGE mappings get flushed as well) 209 */ 210 __flush_tlb_one(vaddr); 211} 212 213void set_pte_vaddr(unsigned long vaddr, pte_t pteval) 214{ 215 pgd_t *pgd; 216 pud_t *pud_page; 217 218 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval)); 219 220 pgd = pgd_offset_k(vaddr); 221 if (pgd_none(*pgd)) { 222 printk(KERN_ERR 223 "PGD FIXMAP MISSING, it should be setup in head.S!\n"); 224 return; 225 } 226 pud_page = (pud_t*)pgd_page_vaddr(*pgd); 227 set_pte_vaddr_pud(pud_page, vaddr, pteval); 228} 229 230pmd_t * __init populate_extra_pmd(unsigned long vaddr) 231{ 232 pgd_t *pgd; 233 pud_t *pud; 234 235 pgd = pgd_offset_k(vaddr); 236 pud = fill_pud(pgd, vaddr); 237 return fill_pmd(pud, vaddr); 238} 239 240pte_t * __init populate_extra_pte(unsigned long vaddr) 241{ 242 pmd_t *pmd; 243 244 pmd = populate_extra_pmd(vaddr); 245 return fill_pte(pmd, vaddr); 246} 247 248/* 249 * Create large page table mappings for a range of physical addresses. 250 */ 251static void __init __init_extra_mapping(unsigned long phys, unsigned long size, 252 pgprot_t prot) 253{ 254 pgd_t *pgd; 255 pud_t *pud; 256 pmd_t *pmd; 257 258 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK)); 259 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) { 260 pgd = pgd_offset_k((unsigned long)__va(phys)); 261 if (pgd_none(*pgd)) { 262 pud = (pud_t *) spp_getpage(); 263 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE | 264 _PAGE_USER)); 265 } 266 pud = pud_offset(pgd, (unsigned long)__va(phys)); 267 if (pud_none(*pud)) { 268 pmd = (pmd_t *) spp_getpage(); 269 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | 270 _PAGE_USER)); 271 } 272 pmd = pmd_offset(pud, phys); 273 BUG_ON(!pmd_none(*pmd)); 274 set_pmd(pmd, __pmd(phys | pgprot_val(prot))); 275 } 276} 277 278void __init init_extra_mapping_wb(unsigned long phys, unsigned long size) 279{ 280 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE); 281} 282 283void __init init_extra_mapping_uc(unsigned long phys, unsigned long size) 284{ 285 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE); 286} 287 288/* 289 * The head.S code sets up the kernel high mapping: 290 * 291 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text) 292 * 293 * phys_addr holds the negative offset to the kernel, which is added 294 * to the compile time generated pmds. This results in invalid pmds up 295 * to the point where we hit the physaddr 0 mapping. 296 * 297 * We limit the mappings to the region from _text to _end. _end is 298 * rounded up to the 2MB boundary. This catches the invalid pmds as 299 * well, as they are located before _text: 300 */ 301void __init cleanup_highmap(void) 302{ 303 unsigned long vaddr = __START_KERNEL_map; 304 unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1; 305 pmd_t *pmd = level2_kernel_pgt; 306 pmd_t *last_pmd = pmd + PTRS_PER_PMD; 307 308 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) { 309 if (pmd_none(*pmd)) 310 continue; 311 if (vaddr < (unsigned long) _text || vaddr > end) 312 set_pmd(pmd, __pmd(0)); 313 } 314} 315 316static __ref void *alloc_low_page(unsigned long *phys) 317{ 318 unsigned long pfn = pgt_buf_end++; 319 void *adr; 320 321 if (after_bootmem) { 322 adr = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK); 323 *phys = __pa(adr); 324 325 return adr; 326 } 327 328 if (pfn >= pgt_buf_top) 329 panic("alloc_low_page: ran out of memory"); 330 331 adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE); 332 clear_page(adr); 333 *phys = pfn * PAGE_SIZE; 334 return adr; 335} 336 337static __ref void *map_low_page(void *virt) 338{ 339 void *adr; 340 unsigned long phys, left; 341 342 if (after_bootmem) 343 return virt; 344 345 phys = __pa(virt); 346 left = phys & (PAGE_SIZE - 1); 347 adr = early_memremap(phys & PAGE_MASK, PAGE_SIZE); 348 adr = (void *)(((unsigned long)adr) | left); 349 350 return adr; 351} 352 353static __ref void unmap_low_page(void *adr) 354{ 355 if (after_bootmem) 356 return; 357 358 early_iounmap((void *)((unsigned long)adr & PAGE_MASK), PAGE_SIZE); 359} 360 361static unsigned long __meminit 362phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end, 363 pgprot_t prot) 364{ 365 unsigned pages = 0; 366 unsigned long last_map_addr = end; 367 int i; 368 369 pte_t *pte = pte_page + pte_index(addr); 370 371 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) { 372 373 if (addr >= end) { 374 if (!after_bootmem) { 375 for(; i < PTRS_PER_PTE; i++, pte++) 376 set_pte(pte, __pte(0)); 377 } 378 break; 379 } 380 381 /* 382 * We will re-use the existing mapping. 383 * Xen for example has some special requirements, like mapping 384 * pagetable pages as RO. So assume someone who pre-setup 385 * these mappings are more intelligent. 386 */ 387 if (pte_val(*pte)) { 388 pages++; 389 continue; 390 } 391 392 if (0) 393 printk(" pte=%p addr=%lx pte=%016lx\n", 394 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte); 395 pages++; 396 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot)); 397 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE; 398 } 399 400 update_page_count(PG_LEVEL_4K, pages); 401 402 return last_map_addr; 403} 404 405static unsigned long __meminit 406phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, 407 unsigned long page_size_mask, pgprot_t prot) 408{ 409 unsigned long pages = 0; 410 unsigned long last_map_addr = end; 411 412 int i = pmd_index(address); 413 414 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) { 415 unsigned long pte_phys; 416 pmd_t *pmd = pmd_page + pmd_index(address); 417 pte_t *pte; 418 pgprot_t new_prot = prot; 419 420 if (address >= end) { 421 if (!after_bootmem) { 422 for (; i < PTRS_PER_PMD; i++, pmd++) 423 set_pmd(pmd, __pmd(0)); 424 } 425 break; 426 } 427 428 if (pmd_val(*pmd)) { 429 if (!pmd_large(*pmd)) { 430 spin_lock(&init_mm.page_table_lock); 431 pte = map_low_page((pte_t *)pmd_page_vaddr(*pmd)); 432 last_map_addr = phys_pte_init(pte, address, 433 end, prot); 434 unmap_low_page(pte); 435 spin_unlock(&init_mm.page_table_lock); 436 continue; 437 } 438 /* 439 * If we are ok with PG_LEVEL_2M mapping, then we will 440 * use the existing mapping, 441 * 442 * Otherwise, we will split the large page mapping but 443 * use the same existing protection bits except for 444 * large page, so that we don't violate Intel's TLB 445 * Application note (317080) which says, while changing 446 * the page sizes, new and old translations should 447 * not differ with respect to page frame and 448 * attributes. 449 */ 450 if (page_size_mask & (1 << PG_LEVEL_2M)) { 451 pages++; 452 continue; 453 } 454 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); 455 } 456 457 if (page_size_mask & (1<<PG_LEVEL_2M)) { 458 pages++; 459 spin_lock(&init_mm.page_table_lock); 460 set_pte((pte_t *)pmd, 461 pfn_pte(address >> PAGE_SHIFT, 462 __pgprot(pgprot_val(prot) | _PAGE_PSE))); 463 spin_unlock(&init_mm.page_table_lock); 464 last_map_addr = (address & PMD_MASK) + PMD_SIZE; 465 continue; 466 } 467 468 pte = alloc_low_page(&pte_phys); 469 last_map_addr = phys_pte_init(pte, address, end, new_prot); 470 unmap_low_page(pte); 471 472 spin_lock(&init_mm.page_table_lock); 473 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys)); 474 spin_unlock(&init_mm.page_table_lock); 475 } 476 update_page_count(PG_LEVEL_2M, pages); 477 return last_map_addr; 478} 479 480static unsigned long __meminit 481phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, 482 unsigned long page_size_mask) 483{ 484 unsigned long pages = 0; 485 unsigned long last_map_addr = end; 486 int i = pud_index(addr); 487 488 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) { 489 unsigned long pmd_phys; 490 pud_t *pud = pud_page + pud_index(addr); 491 pmd_t *pmd; 492 pgprot_t prot = PAGE_KERNEL; 493 494 if (addr >= end) 495 break; 496 497 if (!after_bootmem && 498 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) { 499 set_pud(pud, __pud(0)); 500 continue; 501 } 502 503 if (pud_val(*pud)) { 504 if (!pud_large(*pud)) { 505 pmd = map_low_page(pmd_offset(pud, 0)); 506 last_map_addr = phys_pmd_init(pmd, addr, end, 507 page_size_mask, prot); 508 unmap_low_page(pmd); 509 __flush_tlb_all(); 510 continue; 511 } 512 /* 513 * If we are ok with PG_LEVEL_1G mapping, then we will 514 * use the existing mapping. 515 * 516 * Otherwise, we will split the gbpage mapping but use 517 * the same existing protection bits except for large 518 * page, so that we don't violate Intel's TLB 519 * Application note (317080) which says, while changing 520 * the page sizes, new and old translations should 521 * not differ with respect to page frame and 522 * attributes. 523 */ 524 if (page_size_mask & (1 << PG_LEVEL_1G)) { 525 pages++; 526 continue; 527 } 528 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud)); 529 } 530 531 if (page_size_mask & (1<<PG_LEVEL_1G)) { 532 pages++; 533 spin_lock(&init_mm.page_table_lock); 534 set_pte((pte_t *)pud, 535 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE)); 536 spin_unlock(&init_mm.page_table_lock); 537 last_map_addr = (addr & PUD_MASK) + PUD_SIZE; 538 continue; 539 } 540 541 pmd = alloc_low_page(&pmd_phys); 542 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask, 543 prot); 544 unmap_low_page(pmd); 545 546 spin_lock(&init_mm.page_table_lock); 547 pud_populate(&init_mm, pud, __va(pmd_phys)); 548 spin_unlock(&init_mm.page_table_lock); 549 } 550 __flush_tlb_all(); 551 552 update_page_count(PG_LEVEL_1G, pages); 553 554 return last_map_addr; 555} 556 557unsigned long __meminit 558kernel_physical_mapping_init(unsigned long start, 559 unsigned long end, 560 unsigned long page_size_mask) 561{ 562 bool pgd_changed = false; 563 unsigned long next, last_map_addr = end; 564 unsigned long addr; 565 566 start = (unsigned long)__va(start); 567 end = (unsigned long)__va(end); 568 addr = start; 569 570 for (; start < end; start = next) { 571 pgd_t *pgd = pgd_offset_k(start); 572 unsigned long pud_phys; 573 pud_t *pud; 574 575 next = (start + PGDIR_SIZE) & PGDIR_MASK; 576 if (next > end) 577 next = end; 578 579 if (pgd_val(*pgd)) { 580 pud = map_low_page((pud_t *)pgd_page_vaddr(*pgd)); 581 last_map_addr = phys_pud_init(pud, __pa(start), 582 __pa(end), page_size_mask); 583 unmap_low_page(pud); 584 continue; 585 } 586 587 pud = alloc_low_page(&pud_phys); 588 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next), 589 page_size_mask); 590 unmap_low_page(pud); 591 592 spin_lock(&init_mm.page_table_lock); 593 pgd_populate(&init_mm, pgd, __va(pud_phys)); 594 spin_unlock(&init_mm.page_table_lock); 595 pgd_changed = true; 596 } 597 598 if (pgd_changed) 599 sync_global_pgds(addr, end); 600 601 __flush_tlb_all(); 602 603 return last_map_addr; 604} 605 606#ifndef CONFIG_NUMA 607void __init initmem_init(void) 608{ 609 memblock_x86_register_active_regions(0, 0, max_pfn); 610} 611#endif 612 613void __init paging_init(void) 614{ 615 unsigned long max_zone_pfns[MAX_NR_ZONES]; 616 617 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 618 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 619 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 620 max_zone_pfns[ZONE_NORMAL] = max_pfn; 621 622 sparse_memory_present_with_active_regions(MAX_NUMNODES); 623 sparse_init(); 624 625 /* 626 * clear the default setting with node 0 627 * note: don't use nodes_clear here, that is really clearing when 628 * numa support is not compiled in, and later node_set_state 629 * will not set it back. 630 */ 631 node_clear_state(0, N_NORMAL_MEMORY); 632 633 free_area_init_nodes(max_zone_pfns); 634} 635 636/* 637 * Memory hotplug specific functions 638 */ 639#ifdef CONFIG_MEMORY_HOTPLUG 640/* 641 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 642 * updating. 643 */ 644static void update_end_of_memory_vars(u64 start, u64 size) 645{ 646 unsigned long end_pfn = PFN_UP(start + size); 647 648 if (end_pfn > max_pfn) { 649 max_pfn = end_pfn; 650 max_low_pfn = end_pfn; 651 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 652 } 653} 654 655/* 656 * Memory is added always to NORMAL zone. This means you will never get 657 * additional DMA/DMA32 memory. 658 */ 659int arch_add_memory(int nid, u64 start, u64 size) 660{ 661 struct pglist_data *pgdat = NODE_DATA(nid); 662 struct zone *zone = pgdat->node_zones + ZONE_NORMAL; 663 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT; 664 unsigned long nr_pages = size >> PAGE_SHIFT; 665 int ret; 666 667 last_mapped_pfn = init_memory_mapping(start, start + size); 668 if (last_mapped_pfn > max_pfn_mapped) 669 max_pfn_mapped = last_mapped_pfn; 670 671 ret = __add_pages(nid, zone, start_pfn, nr_pages); 672 WARN_ON_ONCE(ret); 673 674 /* update max_pfn, max_low_pfn and high_memory */ 675 update_end_of_memory_vars(start, size); 676 677 return ret; 678} 679EXPORT_SYMBOL_GPL(arch_add_memory); 680 681#if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA) 682int memory_add_physaddr_to_nid(u64 start) 683{ 684 return 0; 685} 686EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); 687#endif 688 689#endif /* CONFIG_MEMORY_HOTPLUG */ 690 691static struct kcore_list kcore_vsyscall; 692 693void __init mem_init(void) 694{ 695 long codesize, reservedpages, datasize, initsize; 696 unsigned long absent_pages; 697 698 pci_iommu_alloc(); 699 700 /* clear_bss() already clear the empty_zero_page */ 701 702 reservedpages = 0; 703 704 /* this will put all low memory onto the freelists */ 705#ifdef CONFIG_NUMA 706 totalram_pages = numa_free_all_bootmem(); 707#else 708 totalram_pages = free_all_bootmem(); 709#endif 710 711 absent_pages = absent_pages_in_range(0, max_pfn); 712 reservedpages = max_pfn - totalram_pages - absent_pages; 713 after_bootmem = 1; 714 715 codesize = (unsigned long) &_etext - (unsigned long) &_text; 716 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 717 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 718 719 /* Register memory areas for /proc/kcore */ 720 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START, 721 VSYSCALL_END - VSYSCALL_START, KCORE_OTHER); 722 723 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 724 "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n", 725 nr_free_pages() << (PAGE_SHIFT-10), 726 max_pfn << (PAGE_SHIFT-10), 727 codesize >> 10, 728 absent_pages << (PAGE_SHIFT-10), 729 reservedpages << (PAGE_SHIFT-10), 730 datasize >> 10, 731 initsize >> 10); 732} 733 734#ifdef CONFIG_DEBUG_RODATA 735const int rodata_test_data = 0xC3; 736EXPORT_SYMBOL_GPL(rodata_test_data); 737 738int kernel_set_to_readonly; 739 740void set_kernel_text_rw(void) 741{ 742 unsigned long start = PFN_ALIGN(_text); 743 unsigned long end = PFN_ALIGN(__stop___ex_table); 744 745 if (!kernel_set_to_readonly) 746 return; 747 748 pr_debug("Set kernel text: %lx - %lx for read write\n", 749 start, end); 750 751 /* 752 * Make the kernel identity mapping for text RW. Kernel text 753 * mapping will always be RO. Refer to the comment in 754 * static_protections() in pageattr.c 755 */ 756 set_memory_rw(start, (end - start) >> PAGE_SHIFT); 757} 758 759void set_kernel_text_ro(void) 760{ 761 unsigned long start = PFN_ALIGN(_text); 762 unsigned long end = PFN_ALIGN(__stop___ex_table); 763 764 if (!kernel_set_to_readonly) 765 return; 766 767 pr_debug("Set kernel text: %lx - %lx for read only\n", 768 start, end); 769 770 /* 771 * Set the kernel identity mapping for text RO. 772 */ 773 set_memory_ro(start, (end - start) >> PAGE_SHIFT); 774} 775 776void mark_rodata_ro(void) 777{ 778 unsigned long start = PFN_ALIGN(_text); 779 unsigned long rodata_start = 780 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK; 781 unsigned long end = (unsigned long) &__end_rodata_hpage_align; 782 unsigned long text_end = PAGE_ALIGN((unsigned long) &__stop___ex_table); 783 unsigned long rodata_end = PAGE_ALIGN((unsigned long) &__end_rodata); 784 unsigned long data_start = (unsigned long) &_sdata; 785 786 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", 787 (end - start) >> 10); 788 set_memory_ro(start, (end - start) >> PAGE_SHIFT); 789 790 kernel_set_to_readonly = 1; 791 792 /* 793 * The rodata section (but not the kernel text!) should also be 794 * not-executable. 795 */ 796 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT); 797 798 rodata_test(); 799 800#ifdef CONFIG_CPA_DEBUG 801 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end); 802 set_memory_rw(start, (end-start) >> PAGE_SHIFT); 803 804 printk(KERN_INFO "Testing CPA: again\n"); 805 set_memory_ro(start, (end-start) >> PAGE_SHIFT); 806#endif 807 808 free_init_pages("unused kernel memory", 809 (unsigned long) page_address(virt_to_page(text_end)), 810 (unsigned long) 811 page_address(virt_to_page(rodata_start))); 812 free_init_pages("unused kernel memory", 813 (unsigned long) page_address(virt_to_page(rodata_end)), 814 (unsigned long) page_address(virt_to_page(data_start))); 815} 816 817#endif 818 819int kern_addr_valid(unsigned long addr) 820{ 821 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT; 822 pgd_t *pgd; 823 pud_t *pud; 824 pmd_t *pmd; 825 pte_t *pte; 826 827 if (above != 0 && above != -1UL) 828 return 0; 829 830 pgd = pgd_offset_k(addr); 831 if (pgd_none(*pgd)) 832 return 0; 833 834 pud = pud_offset(pgd, addr); 835 if (pud_none(*pud)) 836 return 0; 837 838 pmd = pmd_offset(pud, addr); 839 if (pmd_none(*pmd)) 840 return 0; 841 842 if (pmd_large(*pmd)) 843 return pfn_valid(pmd_pfn(*pmd)); 844 845 pte = pte_offset_kernel(pmd, addr); 846 if (pte_none(*pte)) 847 return 0; 848 849 return pfn_valid(pte_pfn(*pte)); 850} 851 852/* 853 * A pseudo VMA to allow ptrace access for the vsyscall page. This only 854 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does 855 * not need special handling anymore: 856 */ 857static struct vm_area_struct gate_vma = { 858 .vm_start = VSYSCALL_START, 859 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE), 860 .vm_page_prot = PAGE_READONLY_EXEC, 861 .vm_flags = VM_READ | VM_EXEC 862}; 863 864struct vm_area_struct *get_gate_vma(struct mm_struct *mm) 865{ 866#ifdef CONFIG_IA32_EMULATION 867 if (!mm || mm->context.ia32_compat) 868 return NULL; 869#endif 870 return &gate_vma; 871} 872 873int in_gate_area(struct mm_struct *mm, unsigned long addr) 874{ 875 struct vm_area_struct *vma = get_gate_vma(mm); 876 877 if (!vma) 878 return 0; 879 880 return (addr >= vma->vm_start) && (addr < vma->vm_end); 881} 882 883/* 884 * Use this when you have no reliable mm, typically from interrupt 885 * context. It is less reliable than using a task's mm and may give 886 * false positives. 887 */ 888int in_gate_area_no_mm(unsigned long addr) 889{ 890 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END); 891} 892 893const char *arch_vma_name(struct vm_area_struct *vma) 894{ 895 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) 896 return "[vdso]"; 897 if (vma == &gate_vma) 898 return "[vsyscall]"; 899 return NULL; 900} 901 902#ifdef CONFIG_X86_UV 903#define MIN_MEMORY_BLOCK_SIZE (1 << SECTION_SIZE_BITS) 904 905unsigned long memory_block_size_bytes(void) 906{ 907 if (is_uv_system()) { 908 printk(KERN_INFO "UV: memory block size 2GB\n"); 909 return 2UL * 1024 * 1024 * 1024; 910 } 911 return MIN_MEMORY_BLOCK_SIZE; 912} 913#endif 914 915#ifdef CONFIG_SPARSEMEM_VMEMMAP 916/* 917 * Initialise the sparsemem vmemmap using huge-pages at the PMD level. 918 */ 919static long __meminitdata addr_start, addr_end; 920static void __meminitdata *p_start, *p_end; 921static int __meminitdata node_start; 922 923int __meminit 924vmemmap_populate(struct page *start_page, unsigned long size, int node) 925{ 926 unsigned long addr = (unsigned long)start_page; 927 unsigned long end = (unsigned long)(start_page + size); 928 unsigned long next; 929 pgd_t *pgd; 930 pud_t *pud; 931 pmd_t *pmd; 932 933 for (; addr < end; addr = next) { 934 void *p = NULL; 935 936 pgd = vmemmap_pgd_populate(addr, node); 937 if (!pgd) 938 return -ENOMEM; 939 940 pud = vmemmap_pud_populate(pgd, addr, node); 941 if (!pud) 942 return -ENOMEM; 943 944 if (!cpu_has_pse) { 945 next = (addr + PAGE_SIZE) & PAGE_MASK; 946 pmd = vmemmap_pmd_populate(pud, addr, node); 947 948 if (!pmd) 949 return -ENOMEM; 950 951 p = vmemmap_pte_populate(pmd, addr, node); 952 953 if (!p) 954 return -ENOMEM; 955 956 addr_end = addr + PAGE_SIZE; 957 p_end = p + PAGE_SIZE; 958 } else { 959 next = pmd_addr_end(addr, end); 960 961 pmd = pmd_offset(pud, addr); 962 if (pmd_none(*pmd)) { 963 pte_t entry; 964 965 p = vmemmap_alloc_block_buf(PMD_SIZE, node); 966 if (!p) 967 return -ENOMEM; 968 969 entry = pfn_pte(__pa(p) >> PAGE_SHIFT, 970 PAGE_KERNEL_LARGE); 971 set_pmd(pmd, __pmd(pte_val(entry))); 972 973 /* check to see if we have contiguous blocks */ 974 if (p_end != p || node_start != node) { 975 if (p_start) 976 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n", 977 addr_start, addr_end-1, p_start, p_end-1, node_start); 978 addr_start = addr; 979 node_start = node; 980 p_start = p; 981 } 982 983 addr_end = addr + PMD_SIZE; 984 p_end = p + PMD_SIZE; 985 } else 986 vmemmap_verify((pte_t *)pmd, node, addr, next); 987 } 988 989 } 990 sync_global_pgds((unsigned long)start_page, end); 991 return 0; 992} 993 994void __meminit vmemmap_populate_print_last(void) 995{ 996 if (p_start) { 997 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n", 998 addr_start, addr_end-1, p_start, p_end-1, node_start); 999 p_start = NULL; 1000 p_end = NULL; 1001 node_start = 0; 1002 } 1003} 1004#endif 1005