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/memory.h> 31 #include <linux/memory_hotplug.h> 32 #include <linux/memremap.h> 33 #include <linux/nmi.h> 34 #include <linux/gfp.h> 35 #include <linux/kcore.h> 36 37 #include <asm/processor.h> 38 #include <asm/bios_ebda.h> 39 #include <linux/uaccess.h> 40 #include <asm/pgtable.h> 41 #include <asm/pgalloc.h> 42 #include <asm/dma.h> 43 #include <asm/fixmap.h> 44 #include <asm/e820/api.h> 45 #include <asm/apic.h> 46 #include <asm/tlb.h> 47 #include <asm/mmu_context.h> 48 #include <asm/proto.h> 49 #include <asm/smp.h> 50 #include <asm/sections.h> 51 #include <asm/kdebug.h> 52 #include <asm/numa.h> 53 #include <asm/set_memory.h> 54 #include <asm/init.h> 55 #include <asm/uv/uv.h> 56 #include <asm/setup.h> 57 58 #include "mm_internal.h" 59 60 #include "ident_map.c" 61 62 /* 63 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the 64 * physical space so we can cache the place of the first one and move 65 * around without checking the pgd every time. 66 */ 67 68 /* Bits supported by the hardware: */ 69 pteval_t __supported_pte_mask __read_mostly = ~0; 70 /* Bits allowed in normal kernel mappings: */ 71 pteval_t __default_kernel_pte_mask __read_mostly = ~0; 72 EXPORT_SYMBOL_GPL(__supported_pte_mask); 73 /* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */ 74 EXPORT_SYMBOL(__default_kernel_pte_mask); 75 76 int force_personality32; 77 78 /* 79 * noexec32=on|off 80 * Control non executable heap for 32bit processes. 81 * To control the stack too use noexec=off 82 * 83 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default) 84 * off PROT_READ implies PROT_EXEC 85 */ 86 static int __init nonx32_setup(char *str) 87 { 88 if (!strcmp(str, "on")) 89 force_personality32 &= ~READ_IMPLIES_EXEC; 90 else if (!strcmp(str, "off")) 91 force_personality32 |= READ_IMPLIES_EXEC; 92 return 1; 93 } 94 __setup("noexec32=", nonx32_setup); 95 96 static void sync_global_pgds_l5(unsigned long start, unsigned long end) 97 { 98 unsigned long addr; 99 100 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 101 const pgd_t *pgd_ref = pgd_offset_k(addr); 102 struct page *page; 103 104 /* Check for overflow */ 105 if (addr < start) 106 break; 107 108 if (pgd_none(*pgd_ref)) 109 continue; 110 111 spin_lock(&pgd_lock); 112 list_for_each_entry(page, &pgd_list, lru) { 113 pgd_t *pgd; 114 spinlock_t *pgt_lock; 115 116 pgd = (pgd_t *)page_address(page) + pgd_index(addr); 117 /* the pgt_lock only for Xen */ 118 pgt_lock = &pgd_page_get_mm(page)->page_table_lock; 119 spin_lock(pgt_lock); 120 121 if (!pgd_none(*pgd_ref) && !pgd_none(*pgd)) 122 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref)); 123 124 if (pgd_none(*pgd)) 125 set_pgd(pgd, *pgd_ref); 126 127 spin_unlock(pgt_lock); 128 } 129 spin_unlock(&pgd_lock); 130 } 131 } 132 133 static void sync_global_pgds_l4(unsigned long start, unsigned long end) 134 { 135 unsigned long addr; 136 137 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 138 pgd_t *pgd_ref = pgd_offset_k(addr); 139 const p4d_t *p4d_ref; 140 struct page *page; 141 142 /* 143 * With folded p4d, pgd_none() is always false, we need to 144 * handle synchonization on p4d level. 145 */ 146 MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref)); 147 p4d_ref = p4d_offset(pgd_ref, addr); 148 149 if (p4d_none(*p4d_ref)) 150 continue; 151 152 spin_lock(&pgd_lock); 153 list_for_each_entry(page, &pgd_list, lru) { 154 pgd_t *pgd; 155 p4d_t *p4d; 156 spinlock_t *pgt_lock; 157 158 pgd = (pgd_t *)page_address(page) + pgd_index(addr); 159 p4d = p4d_offset(pgd, addr); 160 /* the pgt_lock only for Xen */ 161 pgt_lock = &pgd_page_get_mm(page)->page_table_lock; 162 spin_lock(pgt_lock); 163 164 if (!p4d_none(*p4d_ref) && !p4d_none(*p4d)) 165 BUG_ON(p4d_page_vaddr(*p4d) 166 != p4d_page_vaddr(*p4d_ref)); 167 168 if (p4d_none(*p4d)) 169 set_p4d(p4d, *p4d_ref); 170 171 spin_unlock(pgt_lock); 172 } 173 spin_unlock(&pgd_lock); 174 } 175 } 176 177 /* 178 * When memory was added make sure all the processes MM have 179 * suitable PGD entries in the local PGD level page. 180 */ 181 void sync_global_pgds(unsigned long start, unsigned long end) 182 { 183 if (pgtable_l5_enabled) 184 sync_global_pgds_l5(start, end); 185 else 186 sync_global_pgds_l4(start, end); 187 } 188 189 /* 190 * NOTE: This function is marked __ref because it calls __init function 191 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0. 192 */ 193 static __ref void *spp_getpage(void) 194 { 195 void *ptr; 196 197 if (after_bootmem) 198 ptr = (void *) get_zeroed_page(GFP_ATOMIC); 199 else 200 ptr = alloc_bootmem_pages(PAGE_SIZE); 201 202 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) { 203 panic("set_pte_phys: cannot allocate page data %s\n", 204 after_bootmem ? "after bootmem" : ""); 205 } 206 207 pr_debug("spp_getpage %p\n", ptr); 208 209 return ptr; 210 } 211 212 static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr) 213 { 214 if (pgd_none(*pgd)) { 215 p4d_t *p4d = (p4d_t *)spp_getpage(); 216 pgd_populate(&init_mm, pgd, p4d); 217 if (p4d != p4d_offset(pgd, 0)) 218 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n", 219 p4d, p4d_offset(pgd, 0)); 220 } 221 return p4d_offset(pgd, vaddr); 222 } 223 224 static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr) 225 { 226 if (p4d_none(*p4d)) { 227 pud_t *pud = (pud_t *)spp_getpage(); 228 p4d_populate(&init_mm, p4d, pud); 229 if (pud != pud_offset(p4d, 0)) 230 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n", 231 pud, pud_offset(p4d, 0)); 232 } 233 return pud_offset(p4d, vaddr); 234 } 235 236 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr) 237 { 238 if (pud_none(*pud)) { 239 pmd_t *pmd = (pmd_t *) spp_getpage(); 240 pud_populate(&init_mm, pud, pmd); 241 if (pmd != pmd_offset(pud, 0)) 242 printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n", 243 pmd, pmd_offset(pud, 0)); 244 } 245 return pmd_offset(pud, vaddr); 246 } 247 248 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr) 249 { 250 if (pmd_none(*pmd)) { 251 pte_t *pte = (pte_t *) spp_getpage(); 252 pmd_populate_kernel(&init_mm, pmd, pte); 253 if (pte != pte_offset_kernel(pmd, 0)) 254 printk(KERN_ERR "PAGETABLE BUG #03!\n"); 255 } 256 return pte_offset_kernel(pmd, vaddr); 257 } 258 259 static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte) 260 { 261 pmd_t *pmd = fill_pmd(pud, vaddr); 262 pte_t *pte = fill_pte(pmd, vaddr); 263 264 set_pte(pte, new_pte); 265 266 /* 267 * It's enough to flush this one mapping. 268 * (PGE mappings get flushed as well) 269 */ 270 __flush_tlb_one_kernel(vaddr); 271 } 272 273 void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte) 274 { 275 p4d_t *p4d = p4d_page + p4d_index(vaddr); 276 pud_t *pud = fill_pud(p4d, vaddr); 277 278 __set_pte_vaddr(pud, vaddr, new_pte); 279 } 280 281 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte) 282 { 283 pud_t *pud = pud_page + pud_index(vaddr); 284 285 __set_pte_vaddr(pud, vaddr, new_pte); 286 } 287 288 void set_pte_vaddr(unsigned long vaddr, pte_t pteval) 289 { 290 pgd_t *pgd; 291 p4d_t *p4d_page; 292 293 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval)); 294 295 pgd = pgd_offset_k(vaddr); 296 if (pgd_none(*pgd)) { 297 printk(KERN_ERR 298 "PGD FIXMAP MISSING, it should be setup in head.S!\n"); 299 return; 300 } 301 302 p4d_page = p4d_offset(pgd, 0); 303 set_pte_vaddr_p4d(p4d_page, vaddr, pteval); 304 } 305 306 pmd_t * __init populate_extra_pmd(unsigned long vaddr) 307 { 308 pgd_t *pgd; 309 p4d_t *p4d; 310 pud_t *pud; 311 312 pgd = pgd_offset_k(vaddr); 313 p4d = fill_p4d(pgd, vaddr); 314 pud = fill_pud(p4d, vaddr); 315 return fill_pmd(pud, vaddr); 316 } 317 318 pte_t * __init populate_extra_pte(unsigned long vaddr) 319 { 320 pmd_t *pmd; 321 322 pmd = populate_extra_pmd(vaddr); 323 return fill_pte(pmd, vaddr); 324 } 325 326 /* 327 * Create large page table mappings for a range of physical addresses. 328 */ 329 static void __init __init_extra_mapping(unsigned long phys, unsigned long size, 330 enum page_cache_mode cache) 331 { 332 pgd_t *pgd; 333 p4d_t *p4d; 334 pud_t *pud; 335 pmd_t *pmd; 336 pgprot_t prot; 337 338 pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) | 339 pgprot_val(pgprot_4k_2_large(cachemode2pgprot(cache))); 340 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK)); 341 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) { 342 pgd = pgd_offset_k((unsigned long)__va(phys)); 343 if (pgd_none(*pgd)) { 344 p4d = (p4d_t *) spp_getpage(); 345 set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE | 346 _PAGE_USER)); 347 } 348 p4d = p4d_offset(pgd, (unsigned long)__va(phys)); 349 if (p4d_none(*p4d)) { 350 pud = (pud_t *) spp_getpage(); 351 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE | 352 _PAGE_USER)); 353 } 354 pud = pud_offset(p4d, (unsigned long)__va(phys)); 355 if (pud_none(*pud)) { 356 pmd = (pmd_t *) spp_getpage(); 357 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | 358 _PAGE_USER)); 359 } 360 pmd = pmd_offset(pud, phys); 361 BUG_ON(!pmd_none(*pmd)); 362 set_pmd(pmd, __pmd(phys | pgprot_val(prot))); 363 } 364 } 365 366 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size) 367 { 368 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB); 369 } 370 371 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size) 372 { 373 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC); 374 } 375 376 /* 377 * The head.S code sets up the kernel high mapping: 378 * 379 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text) 380 * 381 * phys_base holds the negative offset to the kernel, which is added 382 * to the compile time generated pmds. This results in invalid pmds up 383 * to the point where we hit the physaddr 0 mapping. 384 * 385 * We limit the mappings to the region from _text to _brk_end. _brk_end 386 * is rounded up to the 2MB boundary. This catches the invalid pmds as 387 * well, as they are located before _text: 388 */ 389 void __init cleanup_highmap(void) 390 { 391 unsigned long vaddr = __START_KERNEL_map; 392 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE; 393 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1; 394 pmd_t *pmd = level2_kernel_pgt; 395 396 /* 397 * Native path, max_pfn_mapped is not set yet. 398 * Xen has valid max_pfn_mapped set in 399 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable(). 400 */ 401 if (max_pfn_mapped) 402 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT); 403 404 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) { 405 if (pmd_none(*pmd)) 406 continue; 407 if (vaddr < (unsigned long) _text || vaddr > end) 408 set_pmd(pmd, __pmd(0)); 409 } 410 } 411 412 /* 413 * Create PTE level page table mapping for physical addresses. 414 * It returns the last physical address mapped. 415 */ 416 static unsigned long __meminit 417 phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end, 418 pgprot_t prot) 419 { 420 unsigned long pages = 0, paddr_next; 421 unsigned long paddr_last = paddr_end; 422 pte_t *pte; 423 int i; 424 425 pte = pte_page + pte_index(paddr); 426 i = pte_index(paddr); 427 428 for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) { 429 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE; 430 if (paddr >= paddr_end) { 431 if (!after_bootmem && 432 !e820__mapped_any(paddr & PAGE_MASK, paddr_next, 433 E820_TYPE_RAM) && 434 !e820__mapped_any(paddr & PAGE_MASK, paddr_next, 435 E820_TYPE_RESERVED_KERN)) 436 set_pte(pte, __pte(0)); 437 continue; 438 } 439 440 /* 441 * We will re-use the existing mapping. 442 * Xen for example has some special requirements, like mapping 443 * pagetable pages as RO. So assume someone who pre-setup 444 * these mappings are more intelligent. 445 */ 446 if (!pte_none(*pte)) { 447 if (!after_bootmem) 448 pages++; 449 continue; 450 } 451 452 if (0) 453 pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr, 454 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte); 455 pages++; 456 set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot)); 457 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE; 458 } 459 460 update_page_count(PG_LEVEL_4K, pages); 461 462 return paddr_last; 463 } 464 465 /* 466 * Create PMD level page table mapping for physical addresses. The virtual 467 * and physical address have to be aligned at this level. 468 * It returns the last physical address mapped. 469 */ 470 static unsigned long __meminit 471 phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end, 472 unsigned long page_size_mask, pgprot_t prot) 473 { 474 unsigned long pages = 0, paddr_next; 475 unsigned long paddr_last = paddr_end; 476 477 int i = pmd_index(paddr); 478 479 for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) { 480 pmd_t *pmd = pmd_page + pmd_index(paddr); 481 pte_t *pte; 482 pgprot_t new_prot = prot; 483 484 paddr_next = (paddr & PMD_MASK) + PMD_SIZE; 485 if (paddr >= paddr_end) { 486 if (!after_bootmem && 487 !e820__mapped_any(paddr & PMD_MASK, paddr_next, 488 E820_TYPE_RAM) && 489 !e820__mapped_any(paddr & PMD_MASK, paddr_next, 490 E820_TYPE_RESERVED_KERN)) 491 set_pmd(pmd, __pmd(0)); 492 continue; 493 } 494 495 if (!pmd_none(*pmd)) { 496 if (!pmd_large(*pmd)) { 497 spin_lock(&init_mm.page_table_lock); 498 pte = (pte_t *)pmd_page_vaddr(*pmd); 499 paddr_last = phys_pte_init(pte, paddr, 500 paddr_end, prot); 501 spin_unlock(&init_mm.page_table_lock); 502 continue; 503 } 504 /* 505 * If we are ok with PG_LEVEL_2M mapping, then we will 506 * use the existing mapping, 507 * 508 * Otherwise, we will split the large page mapping but 509 * use the same existing protection bits except for 510 * large page, so that we don't violate Intel's TLB 511 * Application note (317080) which says, while changing 512 * the page sizes, new and old translations should 513 * not differ with respect to page frame and 514 * attributes. 515 */ 516 if (page_size_mask & (1 << PG_LEVEL_2M)) { 517 if (!after_bootmem) 518 pages++; 519 paddr_last = paddr_next; 520 continue; 521 } 522 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); 523 } 524 525 if (page_size_mask & (1<<PG_LEVEL_2M)) { 526 pages++; 527 spin_lock(&init_mm.page_table_lock); 528 set_pte((pte_t *)pmd, 529 pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT, 530 __pgprot(pgprot_val(prot) | _PAGE_PSE))); 531 spin_unlock(&init_mm.page_table_lock); 532 paddr_last = paddr_next; 533 continue; 534 } 535 536 pte = alloc_low_page(); 537 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot); 538 539 spin_lock(&init_mm.page_table_lock); 540 pmd_populate_kernel(&init_mm, pmd, pte); 541 spin_unlock(&init_mm.page_table_lock); 542 } 543 update_page_count(PG_LEVEL_2M, pages); 544 return paddr_last; 545 } 546 547 /* 548 * Create PUD level page table mapping for physical addresses. The virtual 549 * and physical address do not have to be aligned at this level. KASLR can 550 * randomize virtual addresses up to this level. 551 * It returns the last physical address mapped. 552 */ 553 static unsigned long __meminit 554 phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end, 555 unsigned long page_size_mask) 556 { 557 unsigned long pages = 0, paddr_next; 558 unsigned long paddr_last = paddr_end; 559 unsigned long vaddr = (unsigned long)__va(paddr); 560 int i = pud_index(vaddr); 561 562 for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) { 563 pud_t *pud; 564 pmd_t *pmd; 565 pgprot_t prot = PAGE_KERNEL; 566 567 vaddr = (unsigned long)__va(paddr); 568 pud = pud_page + pud_index(vaddr); 569 paddr_next = (paddr & PUD_MASK) + PUD_SIZE; 570 571 if (paddr >= paddr_end) { 572 if (!after_bootmem && 573 !e820__mapped_any(paddr & PUD_MASK, paddr_next, 574 E820_TYPE_RAM) && 575 !e820__mapped_any(paddr & PUD_MASK, paddr_next, 576 E820_TYPE_RESERVED_KERN)) 577 set_pud(pud, __pud(0)); 578 continue; 579 } 580 581 if (!pud_none(*pud)) { 582 if (!pud_large(*pud)) { 583 pmd = pmd_offset(pud, 0); 584 paddr_last = phys_pmd_init(pmd, paddr, 585 paddr_end, 586 page_size_mask, 587 prot); 588 __flush_tlb_all(); 589 continue; 590 } 591 /* 592 * If we are ok with PG_LEVEL_1G mapping, then we will 593 * use the existing mapping. 594 * 595 * Otherwise, we will split the gbpage mapping but use 596 * the same existing protection bits except for large 597 * page, so that we don't violate Intel's TLB 598 * Application note (317080) which says, while changing 599 * the page sizes, new and old translations should 600 * not differ with respect to page frame and 601 * attributes. 602 */ 603 if (page_size_mask & (1 << PG_LEVEL_1G)) { 604 if (!after_bootmem) 605 pages++; 606 paddr_last = paddr_next; 607 continue; 608 } 609 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud)); 610 } 611 612 if (page_size_mask & (1<<PG_LEVEL_1G)) { 613 pages++; 614 spin_lock(&init_mm.page_table_lock); 615 set_pte((pte_t *)pud, 616 pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT, 617 PAGE_KERNEL_LARGE)); 618 spin_unlock(&init_mm.page_table_lock); 619 paddr_last = paddr_next; 620 continue; 621 } 622 623 pmd = alloc_low_page(); 624 paddr_last = phys_pmd_init(pmd, paddr, paddr_end, 625 page_size_mask, prot); 626 627 spin_lock(&init_mm.page_table_lock); 628 pud_populate(&init_mm, pud, pmd); 629 spin_unlock(&init_mm.page_table_lock); 630 } 631 __flush_tlb_all(); 632 633 update_page_count(PG_LEVEL_1G, pages); 634 635 return paddr_last; 636 } 637 638 static unsigned long __meminit 639 phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end, 640 unsigned long page_size_mask) 641 { 642 unsigned long paddr_next, paddr_last = paddr_end; 643 unsigned long vaddr = (unsigned long)__va(paddr); 644 int i = p4d_index(vaddr); 645 646 if (!pgtable_l5_enabled) 647 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end, page_size_mask); 648 649 for (; i < PTRS_PER_P4D; i++, paddr = paddr_next) { 650 p4d_t *p4d; 651 pud_t *pud; 652 653 vaddr = (unsigned long)__va(paddr); 654 p4d = p4d_page + p4d_index(vaddr); 655 paddr_next = (paddr & P4D_MASK) + P4D_SIZE; 656 657 if (paddr >= paddr_end) { 658 if (!after_bootmem && 659 !e820__mapped_any(paddr & P4D_MASK, paddr_next, 660 E820_TYPE_RAM) && 661 !e820__mapped_any(paddr & P4D_MASK, paddr_next, 662 E820_TYPE_RESERVED_KERN)) 663 set_p4d(p4d, __p4d(0)); 664 continue; 665 } 666 667 if (!p4d_none(*p4d)) { 668 pud = pud_offset(p4d, 0); 669 paddr_last = phys_pud_init(pud, paddr, 670 paddr_end, 671 page_size_mask); 672 __flush_tlb_all(); 673 continue; 674 } 675 676 pud = alloc_low_page(); 677 paddr_last = phys_pud_init(pud, paddr, paddr_end, 678 page_size_mask); 679 680 spin_lock(&init_mm.page_table_lock); 681 p4d_populate(&init_mm, p4d, pud); 682 spin_unlock(&init_mm.page_table_lock); 683 } 684 __flush_tlb_all(); 685 686 return paddr_last; 687 } 688 689 /* 690 * Create page table mapping for the physical memory for specific physical 691 * addresses. The virtual and physical addresses have to be aligned on PMD level 692 * down. It returns the last physical address mapped. 693 */ 694 unsigned long __meminit 695 kernel_physical_mapping_init(unsigned long paddr_start, 696 unsigned long paddr_end, 697 unsigned long page_size_mask) 698 { 699 bool pgd_changed = false; 700 unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last; 701 702 paddr_last = paddr_end; 703 vaddr = (unsigned long)__va(paddr_start); 704 vaddr_end = (unsigned long)__va(paddr_end); 705 vaddr_start = vaddr; 706 707 for (; vaddr < vaddr_end; vaddr = vaddr_next) { 708 pgd_t *pgd = pgd_offset_k(vaddr); 709 p4d_t *p4d; 710 711 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE; 712 713 if (pgd_val(*pgd)) { 714 p4d = (p4d_t *)pgd_page_vaddr(*pgd); 715 paddr_last = phys_p4d_init(p4d, __pa(vaddr), 716 __pa(vaddr_end), 717 page_size_mask); 718 continue; 719 } 720 721 p4d = alloc_low_page(); 722 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end), 723 page_size_mask); 724 725 spin_lock(&init_mm.page_table_lock); 726 if (pgtable_l5_enabled) 727 pgd_populate(&init_mm, pgd, p4d); 728 else 729 p4d_populate(&init_mm, p4d_offset(pgd, vaddr), (pud_t *) p4d); 730 spin_unlock(&init_mm.page_table_lock); 731 pgd_changed = true; 732 } 733 734 if (pgd_changed) 735 sync_global_pgds(vaddr_start, vaddr_end - 1); 736 737 __flush_tlb_all(); 738 739 return paddr_last; 740 } 741 742 #ifndef CONFIG_NUMA 743 void __init initmem_init(void) 744 { 745 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0); 746 } 747 #endif 748 749 void __init paging_init(void) 750 { 751 sparse_memory_present_with_active_regions(MAX_NUMNODES); 752 sparse_init(); 753 754 /* 755 * clear the default setting with node 0 756 * note: don't use nodes_clear here, that is really clearing when 757 * numa support is not compiled in, and later node_set_state 758 * will not set it back. 759 */ 760 node_clear_state(0, N_MEMORY); 761 if (N_MEMORY != N_NORMAL_MEMORY) 762 node_clear_state(0, N_NORMAL_MEMORY); 763 764 zone_sizes_init(); 765 } 766 767 /* 768 * Memory hotplug specific functions 769 */ 770 #ifdef CONFIG_MEMORY_HOTPLUG 771 /* 772 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 773 * updating. 774 */ 775 static void update_end_of_memory_vars(u64 start, u64 size) 776 { 777 unsigned long end_pfn = PFN_UP(start + size); 778 779 if (end_pfn > max_pfn) { 780 max_pfn = end_pfn; 781 max_low_pfn = end_pfn; 782 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 783 } 784 } 785 786 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 787 struct vmem_altmap *altmap, bool want_memblock) 788 { 789 int ret; 790 791 ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); 792 WARN_ON_ONCE(ret); 793 794 /* update max_pfn, max_low_pfn and high_memory */ 795 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 796 nr_pages << PAGE_SHIFT); 797 798 return ret; 799 } 800 801 int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, 802 bool want_memblock) 803 { 804 unsigned long start_pfn = start >> PAGE_SHIFT; 805 unsigned long nr_pages = size >> PAGE_SHIFT; 806 807 init_memory_mapping(start, start + size); 808 809 return add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); 810 } 811 812 #define PAGE_INUSE 0xFD 813 814 static void __meminit free_pagetable(struct page *page, int order) 815 { 816 unsigned long magic; 817 unsigned int nr_pages = 1 << order; 818 819 /* bootmem page has reserved flag */ 820 if (PageReserved(page)) { 821 __ClearPageReserved(page); 822 823 magic = (unsigned long)page->freelist; 824 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) { 825 while (nr_pages--) 826 put_page_bootmem(page++); 827 } else 828 while (nr_pages--) 829 free_reserved_page(page++); 830 } else 831 free_pages((unsigned long)page_address(page), order); 832 } 833 834 static void __meminit free_hugepage_table(struct page *page, 835 struct vmem_altmap *altmap) 836 { 837 if (altmap) 838 vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE); 839 else 840 free_pagetable(page, get_order(PMD_SIZE)); 841 } 842 843 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd) 844 { 845 pte_t *pte; 846 int i; 847 848 for (i = 0; i < PTRS_PER_PTE; i++) { 849 pte = pte_start + i; 850 if (!pte_none(*pte)) 851 return; 852 } 853 854 /* free a pte talbe */ 855 free_pagetable(pmd_page(*pmd), 0); 856 spin_lock(&init_mm.page_table_lock); 857 pmd_clear(pmd); 858 spin_unlock(&init_mm.page_table_lock); 859 } 860 861 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud) 862 { 863 pmd_t *pmd; 864 int i; 865 866 for (i = 0; i < PTRS_PER_PMD; i++) { 867 pmd = pmd_start + i; 868 if (!pmd_none(*pmd)) 869 return; 870 } 871 872 /* free a pmd talbe */ 873 free_pagetable(pud_page(*pud), 0); 874 spin_lock(&init_mm.page_table_lock); 875 pud_clear(pud); 876 spin_unlock(&init_mm.page_table_lock); 877 } 878 879 static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d) 880 { 881 pud_t *pud; 882 int i; 883 884 for (i = 0; i < PTRS_PER_PUD; i++) { 885 pud = pud_start + i; 886 if (!pud_none(*pud)) 887 return; 888 } 889 890 /* free a pud talbe */ 891 free_pagetable(p4d_page(*p4d), 0); 892 spin_lock(&init_mm.page_table_lock); 893 p4d_clear(p4d); 894 spin_unlock(&init_mm.page_table_lock); 895 } 896 897 static void __meminit 898 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end, 899 bool direct) 900 { 901 unsigned long next, pages = 0; 902 pte_t *pte; 903 void *page_addr; 904 phys_addr_t phys_addr; 905 906 pte = pte_start + pte_index(addr); 907 for (; addr < end; addr = next, pte++) { 908 next = (addr + PAGE_SIZE) & PAGE_MASK; 909 if (next > end) 910 next = end; 911 912 if (!pte_present(*pte)) 913 continue; 914 915 /* 916 * We mapped [0,1G) memory as identity mapping when 917 * initializing, in arch/x86/kernel/head_64.S. These 918 * pagetables cannot be removed. 919 */ 920 phys_addr = pte_val(*pte) + (addr & PAGE_MASK); 921 if (phys_addr < (phys_addr_t)0x40000000) 922 return; 923 924 if (PAGE_ALIGNED(addr) && PAGE_ALIGNED(next)) { 925 /* 926 * Do not free direct mapping pages since they were 927 * freed when offlining, or simplely not in use. 928 */ 929 if (!direct) 930 free_pagetable(pte_page(*pte), 0); 931 932 spin_lock(&init_mm.page_table_lock); 933 pte_clear(&init_mm, addr, pte); 934 spin_unlock(&init_mm.page_table_lock); 935 936 /* For non-direct mapping, pages means nothing. */ 937 pages++; 938 } else { 939 /* 940 * If we are here, we are freeing vmemmap pages since 941 * direct mapped memory ranges to be freed are aligned. 942 * 943 * If we are not removing the whole page, it means 944 * other page structs in this page are being used and 945 * we canot remove them. So fill the unused page_structs 946 * with 0xFD, and remove the page when it is wholly 947 * filled with 0xFD. 948 */ 949 memset((void *)addr, PAGE_INUSE, next - addr); 950 951 page_addr = page_address(pte_page(*pte)); 952 if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) { 953 free_pagetable(pte_page(*pte), 0); 954 955 spin_lock(&init_mm.page_table_lock); 956 pte_clear(&init_mm, addr, pte); 957 spin_unlock(&init_mm.page_table_lock); 958 } 959 } 960 } 961 962 /* Call free_pte_table() in remove_pmd_table(). */ 963 flush_tlb_all(); 964 if (direct) 965 update_page_count(PG_LEVEL_4K, -pages); 966 } 967 968 static void __meminit 969 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end, 970 bool direct, struct vmem_altmap *altmap) 971 { 972 unsigned long next, pages = 0; 973 pte_t *pte_base; 974 pmd_t *pmd; 975 void *page_addr; 976 977 pmd = pmd_start + pmd_index(addr); 978 for (; addr < end; addr = next, pmd++) { 979 next = pmd_addr_end(addr, end); 980 981 if (!pmd_present(*pmd)) 982 continue; 983 984 if (pmd_large(*pmd)) { 985 if (IS_ALIGNED(addr, PMD_SIZE) && 986 IS_ALIGNED(next, PMD_SIZE)) { 987 if (!direct) 988 free_hugepage_table(pmd_page(*pmd), 989 altmap); 990 991 spin_lock(&init_mm.page_table_lock); 992 pmd_clear(pmd); 993 spin_unlock(&init_mm.page_table_lock); 994 pages++; 995 } else { 996 /* If here, we are freeing vmemmap pages. */ 997 memset((void *)addr, PAGE_INUSE, next - addr); 998 999 page_addr = page_address(pmd_page(*pmd)); 1000 if (!memchr_inv(page_addr, PAGE_INUSE, 1001 PMD_SIZE)) { 1002 free_hugepage_table(pmd_page(*pmd), 1003 altmap); 1004 1005 spin_lock(&init_mm.page_table_lock); 1006 pmd_clear(pmd); 1007 spin_unlock(&init_mm.page_table_lock); 1008 } 1009 } 1010 1011 continue; 1012 } 1013 1014 pte_base = (pte_t *)pmd_page_vaddr(*pmd); 1015 remove_pte_table(pte_base, addr, next, direct); 1016 free_pte_table(pte_base, pmd); 1017 } 1018 1019 /* Call free_pmd_table() in remove_pud_table(). */ 1020 if (direct) 1021 update_page_count(PG_LEVEL_2M, -pages); 1022 } 1023 1024 static void __meminit 1025 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end, 1026 struct vmem_altmap *altmap, bool direct) 1027 { 1028 unsigned long next, pages = 0; 1029 pmd_t *pmd_base; 1030 pud_t *pud; 1031 void *page_addr; 1032 1033 pud = pud_start + pud_index(addr); 1034 for (; addr < end; addr = next, pud++) { 1035 next = pud_addr_end(addr, end); 1036 1037 if (!pud_present(*pud)) 1038 continue; 1039 1040 if (pud_large(*pud)) { 1041 if (IS_ALIGNED(addr, PUD_SIZE) && 1042 IS_ALIGNED(next, PUD_SIZE)) { 1043 if (!direct) 1044 free_pagetable(pud_page(*pud), 1045 get_order(PUD_SIZE)); 1046 1047 spin_lock(&init_mm.page_table_lock); 1048 pud_clear(pud); 1049 spin_unlock(&init_mm.page_table_lock); 1050 pages++; 1051 } else { 1052 /* If here, we are freeing vmemmap pages. */ 1053 memset((void *)addr, PAGE_INUSE, next - addr); 1054 1055 page_addr = page_address(pud_page(*pud)); 1056 if (!memchr_inv(page_addr, PAGE_INUSE, 1057 PUD_SIZE)) { 1058 free_pagetable(pud_page(*pud), 1059 get_order(PUD_SIZE)); 1060 1061 spin_lock(&init_mm.page_table_lock); 1062 pud_clear(pud); 1063 spin_unlock(&init_mm.page_table_lock); 1064 } 1065 } 1066 1067 continue; 1068 } 1069 1070 pmd_base = pmd_offset(pud, 0); 1071 remove_pmd_table(pmd_base, addr, next, direct, altmap); 1072 free_pmd_table(pmd_base, pud); 1073 } 1074 1075 if (direct) 1076 update_page_count(PG_LEVEL_1G, -pages); 1077 } 1078 1079 static void __meminit 1080 remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end, 1081 struct vmem_altmap *altmap, bool direct) 1082 { 1083 unsigned long next, pages = 0; 1084 pud_t *pud_base; 1085 p4d_t *p4d; 1086 1087 p4d = p4d_start + p4d_index(addr); 1088 for (; addr < end; addr = next, p4d++) { 1089 next = p4d_addr_end(addr, end); 1090 1091 if (!p4d_present(*p4d)) 1092 continue; 1093 1094 BUILD_BUG_ON(p4d_large(*p4d)); 1095 1096 pud_base = pud_offset(p4d, 0); 1097 remove_pud_table(pud_base, addr, next, altmap, direct); 1098 /* 1099 * For 4-level page tables we do not want to free PUDs, but in the 1100 * 5-level case we should free them. This code will have to change 1101 * to adapt for boot-time switching between 4 and 5 level page tables. 1102 */ 1103 if (pgtable_l5_enabled) 1104 free_pud_table(pud_base, p4d); 1105 } 1106 1107 if (direct) 1108 update_page_count(PG_LEVEL_512G, -pages); 1109 } 1110 1111 /* start and end are both virtual address. */ 1112 static void __meminit 1113 remove_pagetable(unsigned long start, unsigned long end, bool direct, 1114 struct vmem_altmap *altmap) 1115 { 1116 unsigned long next; 1117 unsigned long addr; 1118 pgd_t *pgd; 1119 p4d_t *p4d; 1120 1121 for (addr = start; addr < end; addr = next) { 1122 next = pgd_addr_end(addr, end); 1123 1124 pgd = pgd_offset_k(addr); 1125 if (!pgd_present(*pgd)) 1126 continue; 1127 1128 p4d = p4d_offset(pgd, 0); 1129 remove_p4d_table(p4d, addr, next, altmap, direct); 1130 } 1131 1132 flush_tlb_all(); 1133 } 1134 1135 void __ref vmemmap_free(unsigned long start, unsigned long end, 1136 struct vmem_altmap *altmap) 1137 { 1138 remove_pagetable(start, end, false, altmap); 1139 } 1140 1141 #ifdef CONFIG_MEMORY_HOTREMOVE 1142 static void __meminit 1143 kernel_physical_mapping_remove(unsigned long start, unsigned long end) 1144 { 1145 start = (unsigned long)__va(start); 1146 end = (unsigned long)__va(end); 1147 1148 remove_pagetable(start, end, true, NULL); 1149 } 1150 1151 int __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 1152 { 1153 unsigned long start_pfn = start >> PAGE_SHIFT; 1154 unsigned long nr_pages = size >> PAGE_SHIFT; 1155 struct page *page = pfn_to_page(start_pfn); 1156 struct zone *zone; 1157 int ret; 1158 1159 /* With altmap the first mapped page is offset from @start */ 1160 if (altmap) 1161 page += vmem_altmap_offset(altmap); 1162 zone = page_zone(page); 1163 ret = __remove_pages(zone, start_pfn, nr_pages, altmap); 1164 WARN_ON_ONCE(ret); 1165 kernel_physical_mapping_remove(start, start + size); 1166 1167 return ret; 1168 } 1169 #endif 1170 #endif /* CONFIG_MEMORY_HOTPLUG */ 1171 1172 static struct kcore_list kcore_vsyscall; 1173 1174 static void __init register_page_bootmem_info(void) 1175 { 1176 #ifdef CONFIG_NUMA 1177 int i; 1178 1179 for_each_online_node(i) 1180 register_page_bootmem_info_node(NODE_DATA(i)); 1181 #endif 1182 } 1183 1184 void __init mem_init(void) 1185 { 1186 pci_iommu_alloc(); 1187 1188 /* clear_bss() already clear the empty_zero_page */ 1189 1190 /* this will put all memory onto the freelists */ 1191 free_all_bootmem(); 1192 after_bootmem = 1; 1193 x86_init.hyper.init_after_bootmem(); 1194 1195 /* 1196 * Must be done after boot memory is put on freelist, because here we 1197 * might set fields in deferred struct pages that have not yet been 1198 * initialized, and free_all_bootmem() initializes all the reserved 1199 * deferred pages for us. 1200 */ 1201 register_page_bootmem_info(); 1202 1203 /* Register memory areas for /proc/kcore */ 1204 if (get_gate_vma(&init_mm)) 1205 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER); 1206 1207 mem_init_print_info(NULL); 1208 } 1209 1210 int kernel_set_to_readonly; 1211 1212 void set_kernel_text_rw(void) 1213 { 1214 unsigned long start = PFN_ALIGN(_text); 1215 unsigned long end = PFN_ALIGN(__stop___ex_table); 1216 1217 if (!kernel_set_to_readonly) 1218 return; 1219 1220 pr_debug("Set kernel text: %lx - %lx for read write\n", 1221 start, end); 1222 1223 /* 1224 * Make the kernel identity mapping for text RW. Kernel text 1225 * mapping will always be RO. Refer to the comment in 1226 * static_protections() in pageattr.c 1227 */ 1228 set_memory_rw(start, (end - start) >> PAGE_SHIFT); 1229 } 1230 1231 void set_kernel_text_ro(void) 1232 { 1233 unsigned long start = PFN_ALIGN(_text); 1234 unsigned long end = PFN_ALIGN(__stop___ex_table); 1235 1236 if (!kernel_set_to_readonly) 1237 return; 1238 1239 pr_debug("Set kernel text: %lx - %lx for read only\n", 1240 start, end); 1241 1242 /* 1243 * Set the kernel identity mapping for text RO. 1244 */ 1245 set_memory_ro(start, (end - start) >> PAGE_SHIFT); 1246 } 1247 1248 void mark_rodata_ro(void) 1249 { 1250 unsigned long start = PFN_ALIGN(_text); 1251 unsigned long rodata_start = PFN_ALIGN(__start_rodata); 1252 unsigned long end = (unsigned long) &__end_rodata_hpage_align; 1253 unsigned long text_end = PFN_ALIGN(&__stop___ex_table); 1254 unsigned long rodata_end = PFN_ALIGN(&__end_rodata); 1255 unsigned long all_end; 1256 1257 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", 1258 (end - start) >> 10); 1259 set_memory_ro(start, (end - start) >> PAGE_SHIFT); 1260 1261 kernel_set_to_readonly = 1; 1262 1263 /* 1264 * The rodata/data/bss/brk section (but not the kernel text!) 1265 * should also be not-executable. 1266 * 1267 * We align all_end to PMD_SIZE because the existing mapping 1268 * is a full PMD. If we would align _brk_end to PAGE_SIZE we 1269 * split the PMD and the reminder between _brk_end and the end 1270 * of the PMD will remain mapped executable. 1271 * 1272 * Any PMD which was setup after the one which covers _brk_end 1273 * has been zapped already via cleanup_highmem(). 1274 */ 1275 all_end = roundup((unsigned long)_brk_end, PMD_SIZE); 1276 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT); 1277 1278 #ifdef CONFIG_CPA_DEBUG 1279 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end); 1280 set_memory_rw(start, (end-start) >> PAGE_SHIFT); 1281 1282 printk(KERN_INFO "Testing CPA: again\n"); 1283 set_memory_ro(start, (end-start) >> PAGE_SHIFT); 1284 #endif 1285 1286 free_init_pages("unused kernel", 1287 (unsigned long) __va(__pa_symbol(text_end)), 1288 (unsigned long) __va(__pa_symbol(rodata_start))); 1289 free_init_pages("unused kernel", 1290 (unsigned long) __va(__pa_symbol(rodata_end)), 1291 (unsigned long) __va(__pa_symbol(_sdata))); 1292 1293 debug_checkwx(); 1294 1295 /* 1296 * Do this after all of the manipulation of the 1297 * kernel text page tables are complete. 1298 */ 1299 pti_clone_kernel_text(); 1300 } 1301 1302 int kern_addr_valid(unsigned long addr) 1303 { 1304 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT; 1305 pgd_t *pgd; 1306 p4d_t *p4d; 1307 pud_t *pud; 1308 pmd_t *pmd; 1309 pte_t *pte; 1310 1311 if (above != 0 && above != -1UL) 1312 return 0; 1313 1314 pgd = pgd_offset_k(addr); 1315 if (pgd_none(*pgd)) 1316 return 0; 1317 1318 p4d = p4d_offset(pgd, addr); 1319 if (p4d_none(*p4d)) 1320 return 0; 1321 1322 pud = pud_offset(p4d, addr); 1323 if (pud_none(*pud)) 1324 return 0; 1325 1326 if (pud_large(*pud)) 1327 return pfn_valid(pud_pfn(*pud)); 1328 1329 pmd = pmd_offset(pud, addr); 1330 if (pmd_none(*pmd)) 1331 return 0; 1332 1333 if (pmd_large(*pmd)) 1334 return pfn_valid(pmd_pfn(*pmd)); 1335 1336 pte = pte_offset_kernel(pmd, addr); 1337 if (pte_none(*pte)) 1338 return 0; 1339 1340 return pfn_valid(pte_pfn(*pte)); 1341 } 1342 1343 /* 1344 * Block size is the minimum amount of memory which can be hotplugged or 1345 * hotremoved. It must be power of two and must be equal or larger than 1346 * MIN_MEMORY_BLOCK_SIZE. 1347 */ 1348 #define MAX_BLOCK_SIZE (2UL << 30) 1349 1350 /* Amount of ram needed to start using large blocks */ 1351 #define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30) 1352 1353 static unsigned long probe_memory_block_size(void) 1354 { 1355 unsigned long boot_mem_end = max_pfn << PAGE_SHIFT; 1356 unsigned long bz; 1357 1358 /* If this is UV system, always set 2G block size */ 1359 if (is_uv_system()) { 1360 bz = MAX_BLOCK_SIZE; 1361 goto done; 1362 } 1363 1364 /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */ 1365 if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) { 1366 bz = MIN_MEMORY_BLOCK_SIZE; 1367 goto done; 1368 } 1369 1370 /* Find the largest allowed block size that aligns to memory end */ 1371 for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) { 1372 if (IS_ALIGNED(boot_mem_end, bz)) 1373 break; 1374 } 1375 done: 1376 pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20); 1377 1378 return bz; 1379 } 1380 1381 static unsigned long memory_block_size_probed; 1382 unsigned long memory_block_size_bytes(void) 1383 { 1384 if (!memory_block_size_probed) 1385 memory_block_size_probed = probe_memory_block_size(); 1386 1387 return memory_block_size_probed; 1388 } 1389 1390 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1391 /* 1392 * Initialise the sparsemem vmemmap using huge-pages at the PMD level. 1393 */ 1394 static long __meminitdata addr_start, addr_end; 1395 static void __meminitdata *p_start, *p_end; 1396 static int __meminitdata node_start; 1397 1398 static int __meminit vmemmap_populate_hugepages(unsigned long start, 1399 unsigned long end, int node, struct vmem_altmap *altmap) 1400 { 1401 unsigned long addr; 1402 unsigned long next; 1403 pgd_t *pgd; 1404 p4d_t *p4d; 1405 pud_t *pud; 1406 pmd_t *pmd; 1407 1408 for (addr = start; addr < end; addr = next) { 1409 next = pmd_addr_end(addr, end); 1410 1411 pgd = vmemmap_pgd_populate(addr, node); 1412 if (!pgd) 1413 return -ENOMEM; 1414 1415 p4d = vmemmap_p4d_populate(pgd, addr, node); 1416 if (!p4d) 1417 return -ENOMEM; 1418 1419 pud = vmemmap_pud_populate(p4d, addr, node); 1420 if (!pud) 1421 return -ENOMEM; 1422 1423 pmd = pmd_offset(pud, addr); 1424 if (pmd_none(*pmd)) { 1425 void *p; 1426 1427 if (altmap) 1428 p = altmap_alloc_block_buf(PMD_SIZE, altmap); 1429 else 1430 p = vmemmap_alloc_block_buf(PMD_SIZE, node); 1431 if (p) { 1432 pte_t entry; 1433 1434 entry = pfn_pte(__pa(p) >> PAGE_SHIFT, 1435 PAGE_KERNEL_LARGE); 1436 set_pmd(pmd, __pmd(pte_val(entry))); 1437 1438 /* check to see if we have contiguous blocks */ 1439 if (p_end != p || node_start != node) { 1440 if (p_start) 1441 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n", 1442 addr_start, addr_end-1, p_start, p_end-1, node_start); 1443 addr_start = addr; 1444 node_start = node; 1445 p_start = p; 1446 } 1447 1448 addr_end = addr + PMD_SIZE; 1449 p_end = p + PMD_SIZE; 1450 continue; 1451 } else if (altmap) 1452 return -ENOMEM; /* no fallback */ 1453 } else if (pmd_large(*pmd)) { 1454 vmemmap_verify((pte_t *)pmd, node, addr, next); 1455 continue; 1456 } 1457 if (vmemmap_populate_basepages(addr, next, node)) 1458 return -ENOMEM; 1459 } 1460 return 0; 1461 } 1462 1463 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1464 struct vmem_altmap *altmap) 1465 { 1466 int err; 1467 1468 if (boot_cpu_has(X86_FEATURE_PSE)) 1469 err = vmemmap_populate_hugepages(start, end, node, altmap); 1470 else if (altmap) { 1471 pr_err_once("%s: no cpu support for altmap allocations\n", 1472 __func__); 1473 err = -ENOMEM; 1474 } else 1475 err = vmemmap_populate_basepages(start, end, node); 1476 if (!err) 1477 sync_global_pgds(start, end - 1); 1478 return err; 1479 } 1480 1481 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE) 1482 void register_page_bootmem_memmap(unsigned long section_nr, 1483 struct page *start_page, unsigned long nr_pages) 1484 { 1485 unsigned long addr = (unsigned long)start_page; 1486 unsigned long end = (unsigned long)(start_page + nr_pages); 1487 unsigned long next; 1488 pgd_t *pgd; 1489 p4d_t *p4d; 1490 pud_t *pud; 1491 pmd_t *pmd; 1492 unsigned int nr_pmd_pages; 1493 struct page *page; 1494 1495 for (; addr < end; addr = next) { 1496 pte_t *pte = NULL; 1497 1498 pgd = pgd_offset_k(addr); 1499 if (pgd_none(*pgd)) { 1500 next = (addr + PAGE_SIZE) & PAGE_MASK; 1501 continue; 1502 } 1503 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO); 1504 1505 p4d = p4d_offset(pgd, addr); 1506 if (p4d_none(*p4d)) { 1507 next = (addr + PAGE_SIZE) & PAGE_MASK; 1508 continue; 1509 } 1510 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO); 1511 1512 pud = pud_offset(p4d, addr); 1513 if (pud_none(*pud)) { 1514 next = (addr + PAGE_SIZE) & PAGE_MASK; 1515 continue; 1516 } 1517 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO); 1518 1519 if (!boot_cpu_has(X86_FEATURE_PSE)) { 1520 next = (addr + PAGE_SIZE) & PAGE_MASK; 1521 pmd = pmd_offset(pud, addr); 1522 if (pmd_none(*pmd)) 1523 continue; 1524 get_page_bootmem(section_nr, pmd_page(*pmd), 1525 MIX_SECTION_INFO); 1526 1527 pte = pte_offset_kernel(pmd, addr); 1528 if (pte_none(*pte)) 1529 continue; 1530 get_page_bootmem(section_nr, pte_page(*pte), 1531 SECTION_INFO); 1532 } else { 1533 next = pmd_addr_end(addr, end); 1534 1535 pmd = pmd_offset(pud, addr); 1536 if (pmd_none(*pmd)) 1537 continue; 1538 1539 nr_pmd_pages = 1 << get_order(PMD_SIZE); 1540 page = pmd_page(*pmd); 1541 while (nr_pmd_pages--) 1542 get_page_bootmem(section_nr, page++, 1543 SECTION_INFO); 1544 } 1545 } 1546 } 1547 #endif 1548 1549 void __meminit vmemmap_populate_print_last(void) 1550 { 1551 if (p_start) { 1552 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n", 1553 addr_start, addr_end-1, p_start, p_end-1, node_start); 1554 p_start = NULL; 1555 p_end = NULL; 1556 node_start = 0; 1557 } 1558 } 1559 #endif 1560