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/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> 32 33 #include <asm/processor.h> 34 #include <asm/bios_ebda.h> 35 #include <asm/system.h> 36 #include <asm/uaccess.h> 37 #include <asm/pgtable.h> 38 #include <asm/pgalloc.h> 39 #include <asm/dma.h> 40 #include <asm/fixmap.h> 41 #include <asm/e820.h> 42 #include <asm/apic.h> 43 #include <asm/tlb.h> 44 #include <asm/mmu_context.h> 45 #include <asm/proto.h> 46 #include <asm/smp.h> 47 #include <asm/sections.h> 48 #include <asm/kdebug.h> 49 #include <asm/numa.h> 50 #include <asm/cacheflush.h> 51 52 /* 53 * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries. 54 * The direct mapping extends to max_pfn_mapped, so that we can directly access 55 * apertures, ACPI and other tables without having to play with fixmaps. 56 */ 57 unsigned long max_low_pfn_mapped; 58 unsigned long max_pfn_mapped; 59 60 static unsigned long dma_reserve __initdata; 61 62 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 63 64 int direct_gbpages 65 #ifdef CONFIG_DIRECT_GBPAGES 66 = 1 67 #endif 68 ; 69 70 static int __init parse_direct_gbpages_off(char *arg) 71 { 72 direct_gbpages = 0; 73 return 0; 74 } 75 early_param("nogbpages", parse_direct_gbpages_off); 76 77 static int __init parse_direct_gbpages_on(char *arg) 78 { 79 direct_gbpages = 1; 80 return 0; 81 } 82 early_param("gbpages", parse_direct_gbpages_on); 83 84 /* 85 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the 86 * physical space so we can cache the place of the first one and move 87 * around without checking the pgd every time. 88 */ 89 90 int after_bootmem; 91 92 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP; 93 EXPORT_SYMBOL_GPL(__supported_pte_mask); 94 95 static int do_not_nx __cpuinitdata; 96 97 /* 98 * noexec=on|off 99 * Control non-executable mappings for 64-bit processes. 100 * 101 * on Enable (default) 102 * off Disable 103 */ 104 static int __init nonx_setup(char *str) 105 { 106 if (!str) 107 return -EINVAL; 108 if (!strncmp(str, "on", 2)) { 109 __supported_pte_mask |= _PAGE_NX; 110 do_not_nx = 0; 111 } else if (!strncmp(str, "off", 3)) { 112 do_not_nx = 1; 113 __supported_pte_mask &= ~_PAGE_NX; 114 } 115 return 0; 116 } 117 early_param("noexec", nonx_setup); 118 119 void __cpuinit check_efer(void) 120 { 121 unsigned long efer; 122 123 rdmsrl(MSR_EFER, efer); 124 if (!(efer & EFER_NX) || do_not_nx) 125 __supported_pte_mask &= ~_PAGE_NX; 126 } 127 128 int force_personality32; 129 130 /* 131 * noexec32=on|off 132 * Control non executable heap for 32bit processes. 133 * To control the stack too use noexec=off 134 * 135 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default) 136 * off PROT_READ implies PROT_EXEC 137 */ 138 static int __init nonx32_setup(char *str) 139 { 140 if (!strcmp(str, "on")) 141 force_personality32 &= ~READ_IMPLIES_EXEC; 142 else if (!strcmp(str, "off")) 143 force_personality32 |= READ_IMPLIES_EXEC; 144 return 1; 145 } 146 __setup("noexec32=", nonx32_setup); 147 148 /* 149 * NOTE: This function is marked __ref because it calls __init function 150 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0. 151 */ 152 static __ref void *spp_getpage(void) 153 { 154 void *ptr; 155 156 if (after_bootmem) 157 ptr = (void *) get_zeroed_page(GFP_ATOMIC); 158 else 159 ptr = alloc_bootmem_pages(PAGE_SIZE); 160 161 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) { 162 panic("set_pte_phys: cannot allocate page data %s\n", 163 after_bootmem ? "after bootmem" : ""); 164 } 165 166 pr_debug("spp_getpage %p\n", ptr); 167 168 return ptr; 169 } 170 171 void 172 set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte) 173 { 174 pud_t *pud; 175 pmd_t *pmd; 176 pte_t *pte; 177 178 pud = pud_page + pud_index(vaddr); 179 if (pud_none(*pud)) { 180 pmd = (pmd_t *) spp_getpage(); 181 pud_populate(&init_mm, pud, pmd); 182 if (pmd != pmd_offset(pud, 0)) { 183 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n", 184 pmd, pmd_offset(pud, 0)); 185 return; 186 } 187 } 188 pmd = pmd_offset(pud, vaddr); 189 if (pmd_none(*pmd)) { 190 pte = (pte_t *) spp_getpage(); 191 pmd_populate_kernel(&init_mm, pmd, pte); 192 if (pte != pte_offset_kernel(pmd, 0)) { 193 printk(KERN_ERR "PAGETABLE BUG #02!\n"); 194 return; 195 } 196 } 197 198 pte = pte_offset_kernel(pmd, vaddr); 199 set_pte(pte, new_pte); 200 201 /* 202 * It's enough to flush this one mapping. 203 * (PGE mappings get flushed as well) 204 */ 205 __flush_tlb_one(vaddr); 206 } 207 208 void 209 set_pte_vaddr(unsigned long vaddr, pte_t pteval) 210 { 211 pgd_t *pgd; 212 pud_t *pud_page; 213 214 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval)); 215 216 pgd = pgd_offset_k(vaddr); 217 if (pgd_none(*pgd)) { 218 printk(KERN_ERR 219 "PGD FIXMAP MISSING, it should be setup in head.S!\n"); 220 return; 221 } 222 pud_page = (pud_t*)pgd_page_vaddr(*pgd); 223 set_pte_vaddr_pud(pud_page, vaddr, pteval); 224 } 225 226 /* 227 * Create large page table mappings for a range of physical addresses. 228 */ 229 static void __init __init_extra_mapping(unsigned long phys, unsigned long size, 230 pgprot_t prot) 231 { 232 pgd_t *pgd; 233 pud_t *pud; 234 pmd_t *pmd; 235 236 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK)); 237 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) { 238 pgd = pgd_offset_k((unsigned long)__va(phys)); 239 if (pgd_none(*pgd)) { 240 pud = (pud_t *) spp_getpage(); 241 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE | 242 _PAGE_USER)); 243 } 244 pud = pud_offset(pgd, (unsigned long)__va(phys)); 245 if (pud_none(*pud)) { 246 pmd = (pmd_t *) spp_getpage(); 247 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | 248 _PAGE_USER)); 249 } 250 pmd = pmd_offset(pud, phys); 251 BUG_ON(!pmd_none(*pmd)); 252 set_pmd(pmd, __pmd(phys | pgprot_val(prot))); 253 } 254 } 255 256 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size) 257 { 258 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE); 259 } 260 261 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size) 262 { 263 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE); 264 } 265 266 /* 267 * The head.S code sets up the kernel high mapping: 268 * 269 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text) 270 * 271 * phys_addr holds the negative offset to the kernel, which is added 272 * to the compile time generated pmds. This results in invalid pmds up 273 * to the point where we hit the physaddr 0 mapping. 274 * 275 * We limit the mappings to the region from _text to _end. _end is 276 * rounded up to the 2MB boundary. This catches the invalid pmds as 277 * well, as they are located before _text: 278 */ 279 void __init cleanup_highmap(void) 280 { 281 unsigned long vaddr = __START_KERNEL_map; 282 unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1; 283 pmd_t *pmd = level2_kernel_pgt; 284 pmd_t *last_pmd = pmd + PTRS_PER_PMD; 285 286 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) { 287 if (pmd_none(*pmd)) 288 continue; 289 if (vaddr < (unsigned long) _text || vaddr > end) 290 set_pmd(pmd, __pmd(0)); 291 } 292 } 293 294 static unsigned long __initdata table_start; 295 static unsigned long __meminitdata table_end; 296 static unsigned long __meminitdata table_top; 297 298 static __ref void *alloc_low_page(unsigned long *phys) 299 { 300 unsigned long pfn = table_end++; 301 void *adr; 302 303 if (after_bootmem) { 304 adr = (void *)get_zeroed_page(GFP_ATOMIC); 305 *phys = __pa(adr); 306 307 return adr; 308 } 309 310 if (pfn >= table_top) 311 panic("alloc_low_page: ran out of memory"); 312 313 adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE); 314 memset(adr, 0, PAGE_SIZE); 315 *phys = pfn * PAGE_SIZE; 316 return adr; 317 } 318 319 static __ref void unmap_low_page(void *adr) 320 { 321 if (after_bootmem) 322 return; 323 324 early_iounmap(adr, PAGE_SIZE); 325 } 326 327 static unsigned long __meminit 328 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end, 329 pgprot_t prot) 330 { 331 unsigned pages = 0; 332 unsigned long last_map_addr = end; 333 int i; 334 335 pte_t *pte = pte_page + pte_index(addr); 336 337 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) { 338 339 if (addr >= end) { 340 if (!after_bootmem) { 341 for(; i < PTRS_PER_PTE; i++, pte++) 342 set_pte(pte, __pte(0)); 343 } 344 break; 345 } 346 347 /* 348 * We will re-use the existing mapping. 349 * Xen for example has some special requirements, like mapping 350 * pagetable pages as RO. So assume someone who pre-setup 351 * these mappings are more intelligent. 352 */ 353 if (pte_val(*pte)) 354 continue; 355 356 if (0) 357 printk(" pte=%p addr=%lx pte=%016lx\n", 358 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte); 359 pages++; 360 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot)); 361 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE; 362 } 363 364 update_page_count(PG_LEVEL_4K, pages); 365 366 return last_map_addr; 367 } 368 369 static unsigned long __meminit 370 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end, 371 pgprot_t prot) 372 { 373 pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd); 374 375 return phys_pte_init(pte, address, end, prot); 376 } 377 378 static unsigned long __meminit 379 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, 380 unsigned long page_size_mask, pgprot_t prot) 381 { 382 unsigned long pages = 0; 383 unsigned long last_map_addr = end; 384 385 int i = pmd_index(address); 386 387 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) { 388 unsigned long pte_phys; 389 pmd_t *pmd = pmd_page + pmd_index(address); 390 pte_t *pte; 391 pgprot_t new_prot = prot; 392 393 if (address >= end) { 394 if (!after_bootmem) { 395 for (; i < PTRS_PER_PMD; i++, pmd++) 396 set_pmd(pmd, __pmd(0)); 397 } 398 break; 399 } 400 401 if (pmd_val(*pmd)) { 402 if (!pmd_large(*pmd)) { 403 spin_lock(&init_mm.page_table_lock); 404 last_map_addr = phys_pte_update(pmd, address, 405 end, prot); 406 spin_unlock(&init_mm.page_table_lock); 407 continue; 408 } 409 /* 410 * If we are ok with PG_LEVEL_2M mapping, then we will 411 * use the existing mapping, 412 * 413 * Otherwise, we will split the large page mapping but 414 * use the same existing protection bits except for 415 * large page, so that we don't violate Intel's TLB 416 * Application note (317080) which says, while changing 417 * the page sizes, new and old translations should 418 * not differ with respect to page frame and 419 * attributes. 420 */ 421 if (page_size_mask & (1 << PG_LEVEL_2M)) 422 continue; 423 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); 424 } 425 426 if (page_size_mask & (1<<PG_LEVEL_2M)) { 427 pages++; 428 spin_lock(&init_mm.page_table_lock); 429 set_pte((pte_t *)pmd, 430 pfn_pte(address >> PAGE_SHIFT, 431 __pgprot(pgprot_val(prot) | _PAGE_PSE))); 432 spin_unlock(&init_mm.page_table_lock); 433 last_map_addr = (address & PMD_MASK) + PMD_SIZE; 434 continue; 435 } 436 437 pte = alloc_low_page(&pte_phys); 438 last_map_addr = phys_pte_init(pte, address, end, new_prot); 439 unmap_low_page(pte); 440 441 spin_lock(&init_mm.page_table_lock); 442 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys)); 443 spin_unlock(&init_mm.page_table_lock); 444 } 445 update_page_count(PG_LEVEL_2M, pages); 446 return last_map_addr; 447 } 448 449 static unsigned long __meminit 450 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end, 451 unsigned long page_size_mask, pgprot_t prot) 452 { 453 pmd_t *pmd = pmd_offset(pud, 0); 454 unsigned long last_map_addr; 455 456 last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot); 457 __flush_tlb_all(); 458 return last_map_addr; 459 } 460 461 static unsigned long __meminit 462 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, 463 unsigned long page_size_mask) 464 { 465 unsigned long pages = 0; 466 unsigned long last_map_addr = end; 467 int i = pud_index(addr); 468 469 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) { 470 unsigned long pmd_phys; 471 pud_t *pud = pud_page + pud_index(addr); 472 pmd_t *pmd; 473 pgprot_t prot = PAGE_KERNEL; 474 475 if (addr >= end) 476 break; 477 478 if (!after_bootmem && 479 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) { 480 set_pud(pud, __pud(0)); 481 continue; 482 } 483 484 if (pud_val(*pud)) { 485 if (!pud_large(*pud)) { 486 last_map_addr = phys_pmd_update(pud, addr, end, 487 page_size_mask, prot); 488 continue; 489 } 490 /* 491 * If we are ok with PG_LEVEL_1G mapping, then we will 492 * use the existing mapping. 493 * 494 * Otherwise, we will split the gbpage mapping but use 495 * the same existing protection bits except for large 496 * page, so that we don't violate Intel's TLB 497 * Application note (317080) which says, while changing 498 * the page sizes, new and old translations should 499 * not differ with respect to page frame and 500 * attributes. 501 */ 502 if (page_size_mask & (1 << PG_LEVEL_1G)) 503 continue; 504 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud)); 505 } 506 507 if (page_size_mask & (1<<PG_LEVEL_1G)) { 508 pages++; 509 spin_lock(&init_mm.page_table_lock); 510 set_pte((pte_t *)pud, 511 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE)); 512 spin_unlock(&init_mm.page_table_lock); 513 last_map_addr = (addr & PUD_MASK) + PUD_SIZE; 514 continue; 515 } 516 517 pmd = alloc_low_page(&pmd_phys); 518 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask, 519 prot); 520 unmap_low_page(pmd); 521 522 spin_lock(&init_mm.page_table_lock); 523 pud_populate(&init_mm, pud, __va(pmd_phys)); 524 spin_unlock(&init_mm.page_table_lock); 525 } 526 __flush_tlb_all(); 527 528 update_page_count(PG_LEVEL_1G, pages); 529 530 return last_map_addr; 531 } 532 533 static unsigned long __meminit 534 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end, 535 unsigned long page_size_mask) 536 { 537 pud_t *pud; 538 539 pud = (pud_t *)pgd_page_vaddr(*pgd); 540 541 return phys_pud_init(pud, addr, end, page_size_mask); 542 } 543 544 static void __init find_early_table_space(unsigned long end, int use_pse, 545 int use_gbpages) 546 { 547 unsigned long puds, pmds, ptes, tables, start; 548 549 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT; 550 tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); 551 if (use_gbpages) { 552 unsigned long extra; 553 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT); 554 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT; 555 } else 556 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; 557 tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); 558 559 if (use_pse) { 560 unsigned long extra; 561 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT); 562 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT; 563 } else 564 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT; 565 tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE); 566 567 /* 568 * RED-PEN putting page tables only on node 0 could 569 * cause a hotspot and fill up ZONE_DMA. The page tables 570 * need roughly 0.5KB per GB. 571 */ 572 start = 0x8000; 573 table_start = find_e820_area(start, end, tables, PAGE_SIZE); 574 if (table_start == -1UL) 575 panic("Cannot find space for the kernel page tables"); 576 577 table_start >>= PAGE_SHIFT; 578 table_end = table_start; 579 table_top = table_start + (tables >> PAGE_SHIFT); 580 581 printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n", 582 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT); 583 } 584 585 static void __init init_gbpages(void) 586 { 587 if (direct_gbpages && cpu_has_gbpages) 588 printk(KERN_INFO "Using GB pages for direct mapping\n"); 589 else 590 direct_gbpages = 0; 591 } 592 593 static unsigned long __init kernel_physical_mapping_init(unsigned long start, 594 unsigned long end, 595 unsigned long page_size_mask) 596 { 597 598 unsigned long next, last_map_addr = end; 599 600 start = (unsigned long)__va(start); 601 end = (unsigned long)__va(end); 602 603 for (; start < end; start = next) { 604 pgd_t *pgd = pgd_offset_k(start); 605 unsigned long pud_phys; 606 pud_t *pud; 607 608 next = (start + PGDIR_SIZE) & PGDIR_MASK; 609 if (next > end) 610 next = end; 611 612 if (pgd_val(*pgd)) { 613 last_map_addr = phys_pud_update(pgd, __pa(start), 614 __pa(end), page_size_mask); 615 continue; 616 } 617 618 pud = alloc_low_page(&pud_phys); 619 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next), 620 page_size_mask); 621 unmap_low_page(pud); 622 623 spin_lock(&init_mm.page_table_lock); 624 pgd_populate(&init_mm, pgd, __va(pud_phys)); 625 spin_unlock(&init_mm.page_table_lock); 626 } 627 __flush_tlb_all(); 628 629 return last_map_addr; 630 } 631 632 struct map_range { 633 unsigned long start; 634 unsigned long end; 635 unsigned page_size_mask; 636 }; 637 638 #define NR_RANGE_MR 5 639 640 static int save_mr(struct map_range *mr, int nr_range, 641 unsigned long start_pfn, unsigned long end_pfn, 642 unsigned long page_size_mask) 643 { 644 645 if (start_pfn < end_pfn) { 646 if (nr_range >= NR_RANGE_MR) 647 panic("run out of range for init_memory_mapping\n"); 648 mr[nr_range].start = start_pfn<<PAGE_SHIFT; 649 mr[nr_range].end = end_pfn<<PAGE_SHIFT; 650 mr[nr_range].page_size_mask = page_size_mask; 651 nr_range++; 652 } 653 654 return nr_range; 655 } 656 657 /* 658 * Setup the direct mapping of the physical memory at PAGE_OFFSET. 659 * This runs before bootmem is initialized and gets pages directly from 660 * the physical memory. To access them they are temporarily mapped. 661 */ 662 unsigned long __init_refok init_memory_mapping(unsigned long start, 663 unsigned long end) 664 { 665 unsigned long last_map_addr = 0; 666 unsigned long page_size_mask = 0; 667 unsigned long start_pfn, end_pfn; 668 669 struct map_range mr[NR_RANGE_MR]; 670 int nr_range, i; 671 int use_pse, use_gbpages; 672 673 printk(KERN_INFO "init_memory_mapping\n"); 674 675 /* 676 * Find space for the kernel direct mapping tables. 677 * 678 * Later we should allocate these tables in the local node of the 679 * memory mapped. Unfortunately this is done currently before the 680 * nodes are discovered. 681 */ 682 if (!after_bootmem) 683 init_gbpages(); 684 685 #ifdef CONFIG_DEBUG_PAGEALLOC 686 /* 687 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages. 688 * This will simplify cpa(), which otherwise needs to support splitting 689 * large pages into small in interrupt context, etc. 690 */ 691 use_pse = use_gbpages = 0; 692 #else 693 use_pse = cpu_has_pse; 694 use_gbpages = direct_gbpages; 695 #endif 696 697 if (use_gbpages) 698 page_size_mask |= 1 << PG_LEVEL_1G; 699 if (use_pse) 700 page_size_mask |= 1 << PG_LEVEL_2M; 701 702 memset(mr, 0, sizeof(mr)); 703 nr_range = 0; 704 705 /* head if not big page alignment ?*/ 706 start_pfn = start >> PAGE_SHIFT; 707 end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT) 708 << (PMD_SHIFT - PAGE_SHIFT); 709 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); 710 711 /* big page (2M) range*/ 712 start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT) 713 << (PMD_SHIFT - PAGE_SHIFT); 714 end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT) 715 << (PUD_SHIFT - PAGE_SHIFT); 716 if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT))) 717 end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)); 718 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 719 page_size_mask & (1<<PG_LEVEL_2M)); 720 721 /* big page (1G) range */ 722 start_pfn = end_pfn; 723 end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT); 724 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 725 page_size_mask & 726 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G))); 727 728 /* tail is not big page (1G) alignment */ 729 start_pfn = end_pfn; 730 end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT); 731 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 732 page_size_mask & (1<<PG_LEVEL_2M)); 733 734 /* tail is not big page (2M) alignment */ 735 start_pfn = end_pfn; 736 end_pfn = end>>PAGE_SHIFT; 737 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0); 738 739 /* try to merge same page size and continuous */ 740 for (i = 0; nr_range > 1 && i < nr_range - 1; i++) { 741 unsigned long old_start; 742 if (mr[i].end != mr[i+1].start || 743 mr[i].page_size_mask != mr[i+1].page_size_mask) 744 continue; 745 /* move it */ 746 old_start = mr[i].start; 747 memmove(&mr[i], &mr[i+1], 748 (nr_range - 1 - i) * sizeof (struct map_range)); 749 mr[i--].start = old_start; 750 nr_range--; 751 } 752 753 for (i = 0; i < nr_range; i++) 754 printk(KERN_DEBUG " %010lx - %010lx page %s\n", 755 mr[i].start, mr[i].end, 756 (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":( 757 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k")); 758 759 if (!after_bootmem) 760 find_early_table_space(end, use_pse, use_gbpages); 761 762 for (i = 0; i < nr_range; i++) 763 last_map_addr = kernel_physical_mapping_init( 764 mr[i].start, mr[i].end, 765 mr[i].page_size_mask); 766 767 if (!after_bootmem) 768 mmu_cr4_features = read_cr4(); 769 __flush_tlb_all(); 770 771 if (!after_bootmem && table_end > table_start) 772 reserve_early(table_start << PAGE_SHIFT, 773 table_end << PAGE_SHIFT, "PGTABLE"); 774 775 printk(KERN_INFO "last_map_addr: %lx end: %lx\n", 776 last_map_addr, end); 777 778 if (!after_bootmem) 779 early_memtest(start, end); 780 781 return last_map_addr >> PAGE_SHIFT; 782 } 783 784 #ifndef CONFIG_NUMA 785 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn) 786 { 787 unsigned long bootmap_size, bootmap; 788 789 bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT; 790 bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size, 791 PAGE_SIZE); 792 if (bootmap == -1L) 793 panic("Cannot find bootmem map of size %ld\n", bootmap_size); 794 /* don't touch min_low_pfn */ 795 bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT, 796 0, end_pfn); 797 e820_register_active_regions(0, start_pfn, end_pfn); 798 free_bootmem_with_active_regions(0, end_pfn); 799 early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT); 800 reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT); 801 } 802 803 void __init paging_init(void) 804 { 805 unsigned long max_zone_pfns[MAX_NR_ZONES]; 806 807 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 808 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 809 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 810 max_zone_pfns[ZONE_NORMAL] = max_pfn; 811 812 memory_present(0, 0, max_pfn); 813 sparse_init(); 814 free_area_init_nodes(max_zone_pfns); 815 } 816 #endif 817 818 /* 819 * Memory hotplug specific functions 820 */ 821 #ifdef CONFIG_MEMORY_HOTPLUG 822 /* 823 * Memory is added always to NORMAL zone. This means you will never get 824 * additional DMA/DMA32 memory. 825 */ 826 int arch_add_memory(int nid, u64 start, u64 size) 827 { 828 struct pglist_data *pgdat = NODE_DATA(nid); 829 struct zone *zone = pgdat->node_zones + ZONE_NORMAL; 830 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT; 831 unsigned long nr_pages = size >> PAGE_SHIFT; 832 int ret; 833 834 last_mapped_pfn = init_memory_mapping(start, start + size-1); 835 if (last_mapped_pfn > max_pfn_mapped) 836 max_pfn_mapped = last_mapped_pfn; 837 838 ret = __add_pages(zone, start_pfn, nr_pages); 839 WARN_ON(1); 840 841 return ret; 842 } 843 EXPORT_SYMBOL_GPL(arch_add_memory); 844 845 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA) 846 int memory_add_physaddr_to_nid(u64 start) 847 { 848 return 0; 849 } 850 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); 851 #endif 852 853 #endif /* CONFIG_MEMORY_HOTPLUG */ 854 855 /* 856 * devmem_is_allowed() checks to see if /dev/mem access to a certain address 857 * is valid. The argument is a physical page number. 858 * 859 * 860 * On x86, access has to be given to the first megabyte of ram because that area 861 * contains bios code and data regions used by X and dosemu and similar apps. 862 * Access has to be given to non-kernel-ram areas as well, these contain the PCI 863 * mmio resources as well as potential bios/acpi data regions. 864 */ 865 int devmem_is_allowed(unsigned long pagenr) 866 { 867 if (pagenr <= 256) 868 return 1; 869 if (!page_is_ram(pagenr)) 870 return 1; 871 return 0; 872 } 873 874 875 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel, 876 kcore_modules, kcore_vsyscall; 877 878 void __init mem_init(void) 879 { 880 long codesize, reservedpages, datasize, initsize; 881 882 start_periodic_check_for_corruption(); 883 884 pci_iommu_alloc(); 885 886 /* clear_bss() already clear the empty_zero_page */ 887 888 reservedpages = 0; 889 890 /* this will put all low memory onto the freelists */ 891 #ifdef CONFIG_NUMA 892 totalram_pages = numa_free_all_bootmem(); 893 #else 894 totalram_pages = free_all_bootmem(); 895 #endif 896 reservedpages = max_pfn - totalram_pages - 897 absent_pages_in_range(0, max_pfn); 898 after_bootmem = 1; 899 900 codesize = (unsigned long) &_etext - (unsigned long) &_text; 901 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 902 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 903 904 /* Register memory areas for /proc/kcore */ 905 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT); 906 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START, 907 VMALLOC_END-VMALLOC_START); 908 kclist_add(&kcore_kernel, &_stext, _end - _stext); 909 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN); 910 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START, 911 VSYSCALL_END - VSYSCALL_START); 912 913 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 914 "%ldk reserved, %ldk data, %ldk init)\n", 915 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 916 max_pfn << (PAGE_SHIFT-10), 917 codesize >> 10, 918 reservedpages << (PAGE_SHIFT-10), 919 datasize >> 10, 920 initsize >> 10); 921 } 922 923 void free_init_pages(char *what, unsigned long begin, unsigned long end) 924 { 925 unsigned long addr = begin; 926 927 if (addr >= end) 928 return; 929 930 /* 931 * If debugging page accesses then do not free this memory but 932 * mark them not present - any buggy init-section access will 933 * create a kernel page fault: 934 */ 935 #ifdef CONFIG_DEBUG_PAGEALLOC 936 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n", 937 begin, PAGE_ALIGN(end)); 938 set_memory_np(begin, (end - begin) >> PAGE_SHIFT); 939 #else 940 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); 941 942 for (; addr < end; addr += PAGE_SIZE) { 943 ClearPageReserved(virt_to_page(addr)); 944 init_page_count(virt_to_page(addr)); 945 memset((void *)(addr & ~(PAGE_SIZE-1)), 946 POISON_FREE_INITMEM, PAGE_SIZE); 947 free_page(addr); 948 totalram_pages++; 949 } 950 #endif 951 } 952 953 void free_initmem(void) 954 { 955 free_init_pages("unused kernel memory", 956 (unsigned long)(&__init_begin), 957 (unsigned long)(&__init_end)); 958 } 959 960 #ifdef CONFIG_DEBUG_RODATA 961 const int rodata_test_data = 0xC3; 962 EXPORT_SYMBOL_GPL(rodata_test_data); 963 964 void mark_rodata_ro(void) 965 { 966 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata); 967 unsigned long rodata_start = 968 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK; 969 970 #ifdef CONFIG_DYNAMIC_FTRACE 971 /* Dynamic tracing modifies the kernel text section */ 972 start = rodata_start; 973 #endif 974 975 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", 976 (end - start) >> 10); 977 set_memory_ro(start, (end - start) >> PAGE_SHIFT); 978 979 /* 980 * The rodata section (but not the kernel text!) should also be 981 * not-executable. 982 */ 983 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT); 984 985 rodata_test(); 986 987 #ifdef CONFIG_CPA_DEBUG 988 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end); 989 set_memory_rw(start, (end-start) >> PAGE_SHIFT); 990 991 printk(KERN_INFO "Testing CPA: again\n"); 992 set_memory_ro(start, (end-start) >> PAGE_SHIFT); 993 #endif 994 } 995 996 #endif 997 998 #ifdef CONFIG_BLK_DEV_INITRD 999 void free_initrd_mem(unsigned long start, unsigned long end) 1000 { 1001 free_init_pages("initrd memory", start, end); 1002 } 1003 #endif 1004 1005 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len, 1006 int flags) 1007 { 1008 #ifdef CONFIG_NUMA 1009 int nid, next_nid; 1010 int ret; 1011 #endif 1012 unsigned long pfn = phys >> PAGE_SHIFT; 1013 1014 if (pfn >= max_pfn) { 1015 /* 1016 * This can happen with kdump kernels when accessing 1017 * firmware tables: 1018 */ 1019 if (pfn < max_pfn_mapped) 1020 return -EFAULT; 1021 1022 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n", 1023 phys, len); 1024 return -EFAULT; 1025 } 1026 1027 /* Should check here against the e820 map to avoid double free */ 1028 #ifdef CONFIG_NUMA 1029 nid = phys_to_nid(phys); 1030 next_nid = phys_to_nid(phys + len - 1); 1031 if (nid == next_nid) 1032 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags); 1033 else 1034 ret = reserve_bootmem(phys, len, flags); 1035 1036 if (ret != 0) 1037 return ret; 1038 1039 #else 1040 reserve_bootmem(phys, len, BOOTMEM_DEFAULT); 1041 #endif 1042 1043 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) { 1044 dma_reserve += len / PAGE_SIZE; 1045 set_dma_reserve(dma_reserve); 1046 } 1047 1048 return 0; 1049 } 1050 1051 int kern_addr_valid(unsigned long addr) 1052 { 1053 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT; 1054 pgd_t *pgd; 1055 pud_t *pud; 1056 pmd_t *pmd; 1057 pte_t *pte; 1058 1059 if (above != 0 && above != -1UL) 1060 return 0; 1061 1062 pgd = pgd_offset_k(addr); 1063 if (pgd_none(*pgd)) 1064 return 0; 1065 1066 pud = pud_offset(pgd, addr); 1067 if (pud_none(*pud)) 1068 return 0; 1069 1070 pmd = pmd_offset(pud, addr); 1071 if (pmd_none(*pmd)) 1072 return 0; 1073 1074 if (pmd_large(*pmd)) 1075 return pfn_valid(pmd_pfn(*pmd)); 1076 1077 pte = pte_offset_kernel(pmd, addr); 1078 if (pte_none(*pte)) 1079 return 0; 1080 1081 return pfn_valid(pte_pfn(*pte)); 1082 } 1083 1084 /* 1085 * A pseudo VMA to allow ptrace access for the vsyscall page. This only 1086 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does 1087 * not need special handling anymore: 1088 */ 1089 static struct vm_area_struct gate_vma = { 1090 .vm_start = VSYSCALL_START, 1091 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE), 1092 .vm_page_prot = PAGE_READONLY_EXEC, 1093 .vm_flags = VM_READ | VM_EXEC 1094 }; 1095 1096 struct vm_area_struct *get_gate_vma(struct task_struct *tsk) 1097 { 1098 #ifdef CONFIG_IA32_EMULATION 1099 if (test_tsk_thread_flag(tsk, TIF_IA32)) 1100 return NULL; 1101 #endif 1102 return &gate_vma; 1103 } 1104 1105 int in_gate_area(struct task_struct *task, unsigned long addr) 1106 { 1107 struct vm_area_struct *vma = get_gate_vma(task); 1108 1109 if (!vma) 1110 return 0; 1111 1112 return (addr >= vma->vm_start) && (addr < vma->vm_end); 1113 } 1114 1115 /* 1116 * Use this when you have no reliable task/vma, typically from interrupt 1117 * context. It is less reliable than using the task's vma and may give 1118 * false positives: 1119 */ 1120 int in_gate_area_no_task(unsigned long addr) 1121 { 1122 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END); 1123 } 1124 1125 const char *arch_vma_name(struct vm_area_struct *vma) 1126 { 1127 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) 1128 return "[vdso]"; 1129 if (vma == &gate_vma) 1130 return "[vsyscall]"; 1131 return NULL; 1132 } 1133 1134 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1135 /* 1136 * Initialise the sparsemem vmemmap using huge-pages at the PMD level. 1137 */ 1138 static long __meminitdata addr_start, addr_end; 1139 static void __meminitdata *p_start, *p_end; 1140 static int __meminitdata node_start; 1141 1142 int __meminit 1143 vmemmap_populate(struct page *start_page, unsigned long size, int node) 1144 { 1145 unsigned long addr = (unsigned long)start_page; 1146 unsigned long end = (unsigned long)(start_page + size); 1147 unsigned long next; 1148 pgd_t *pgd; 1149 pud_t *pud; 1150 pmd_t *pmd; 1151 1152 for (; addr < end; addr = next) { 1153 void *p = NULL; 1154 1155 pgd = vmemmap_pgd_populate(addr, node); 1156 if (!pgd) 1157 return -ENOMEM; 1158 1159 pud = vmemmap_pud_populate(pgd, addr, node); 1160 if (!pud) 1161 return -ENOMEM; 1162 1163 if (!cpu_has_pse) { 1164 next = (addr + PAGE_SIZE) & PAGE_MASK; 1165 pmd = vmemmap_pmd_populate(pud, addr, node); 1166 1167 if (!pmd) 1168 return -ENOMEM; 1169 1170 p = vmemmap_pte_populate(pmd, addr, node); 1171 1172 if (!p) 1173 return -ENOMEM; 1174 1175 addr_end = addr + PAGE_SIZE; 1176 p_end = p + PAGE_SIZE; 1177 } else { 1178 next = pmd_addr_end(addr, end); 1179 1180 pmd = pmd_offset(pud, addr); 1181 if (pmd_none(*pmd)) { 1182 pte_t entry; 1183 1184 p = vmemmap_alloc_block(PMD_SIZE, node); 1185 if (!p) 1186 return -ENOMEM; 1187 1188 entry = pfn_pte(__pa(p) >> PAGE_SHIFT, 1189 PAGE_KERNEL_LARGE); 1190 set_pmd(pmd, __pmd(pte_val(entry))); 1191 1192 /* check to see if we have contiguous blocks */ 1193 if (p_end != p || node_start != node) { 1194 if (p_start) 1195 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n", 1196 addr_start, addr_end-1, p_start, p_end-1, node_start); 1197 addr_start = addr; 1198 node_start = node; 1199 p_start = p; 1200 } 1201 1202 addr_end = addr + PMD_SIZE; 1203 p_end = p + PMD_SIZE; 1204 } else 1205 vmemmap_verify((pte_t *)pmd, node, addr, next); 1206 } 1207 1208 } 1209 return 0; 1210 } 1211 1212 void __meminit vmemmap_populate_print_last(void) 1213 { 1214 if (p_start) { 1215 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n", 1216 addr_start, addr_end-1, p_start, p_end-1, node_start); 1217 p_start = NULL; 1218 p_end = NULL; 1219 node_start = 0; 1220 } 1221 } 1222 #endif 1223