1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * linux/arch/x86_64/mm/init.c 4 * 5 * Copyright (C) 1995 Linus Torvalds 6 * Copyright (C) 2000 Pavel Machek <pavel@ucw.cz> 7 * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de> 8 */ 9 10#include <linux/signal.h> 11#include <linux/sched.h> 12#include <linux/kernel.h> 13#include <linux/errno.h> 14#include <linux/string.h> 15#include <linux/types.h> 16#include <linux/ptrace.h> 17#include <linux/mman.h> 18#include <linux/mm.h> 19#include <linux/swap.h> 20#include <linux/smp.h> 21#include <linux/init.h> 22#include <linux/initrd.h> 23#include <linux/pagemap.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#include <linux/bootmem_info.h> 37 38#include <asm/processor.h> 39#include <asm/bios_ebda.h> 40#include <linux/uaccess.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#include <asm/ftrace.h> 58 59#include "mm_internal.h" 60 61#include "ident_map.c" 62 63#define DEFINE_POPULATE(fname, type1, type2, init) \ 64static inline void fname##_init(struct mm_struct *mm, \ 65 type1##_t *arg1, type2##_t *arg2, bool init) \ 66{ \ 67 if (init) \ 68 fname##_safe(mm, arg1, arg2); \ 69 else \ 70 fname(mm, arg1, arg2); \ 71} 72 73DEFINE_POPULATE(p4d_populate, p4d, pud, init) 74DEFINE_POPULATE(pgd_populate, pgd, p4d, init) 75DEFINE_POPULATE(pud_populate, pud, pmd, init) 76DEFINE_POPULATE(pmd_populate_kernel, pmd, pte, init) 77 78#define DEFINE_ENTRY(type1, type2, init) \ 79static inline void set_##type1##_init(type1##_t *arg1, \ 80 type2##_t arg2, bool init) \ 81{ \ 82 if (init) \ 83 set_##type1##_safe(arg1, arg2); \ 84 else \ 85 set_##type1(arg1, arg2); \ 86} 87 88DEFINE_ENTRY(p4d, p4d, init) 89DEFINE_ENTRY(pud, pud, init) 90DEFINE_ENTRY(pmd, pmd, init) 91DEFINE_ENTRY(pte, pte, init) 92 93static inline pgprot_t prot_sethuge(pgprot_t prot) 94{ 95 WARN_ON_ONCE(pgprot_val(prot) & _PAGE_PAT); 96 97 return __pgprot(pgprot_val(prot) | _PAGE_PSE); 98} 99 100/* 101 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the 102 * physical space so we can cache the place of the first one and move 103 * around without checking the pgd every time. 104 */ 105 106/* Bits supported by the hardware: */ 107pteval_t __supported_pte_mask __read_mostly = ~0; 108/* Bits allowed in normal kernel mappings: */ 109pteval_t __default_kernel_pte_mask __read_mostly = ~0; 110EXPORT_SYMBOL_GPL(__supported_pte_mask); 111/* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */ 112EXPORT_SYMBOL(__default_kernel_pte_mask); 113 114int force_personality32; 115 116/* 117 * noexec32=on|off 118 * Control non executable heap for 32bit processes. 119 * 120 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default) 121 * off PROT_READ implies PROT_EXEC 122 */ 123static int __init nonx32_setup(char *str) 124{ 125 if (!strcmp(str, "on")) 126 force_personality32 &= ~READ_IMPLIES_EXEC; 127 else if (!strcmp(str, "off")) 128 force_personality32 |= READ_IMPLIES_EXEC; 129 return 1; 130} 131__setup("noexec32=", nonx32_setup); 132 133static void sync_global_pgds_l5(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 const pgd_t *pgd_ref = pgd_offset_k(addr); 139 struct page *page; 140 141 /* Check for overflow */ 142 if (addr < start) 143 break; 144 145 if (pgd_none(*pgd_ref)) 146 continue; 147 148 spin_lock(&pgd_lock); 149 list_for_each_entry(page, &pgd_list, lru) { 150 pgd_t *pgd; 151 spinlock_t *pgt_lock; 152 153 pgd = (pgd_t *)page_address(page) + pgd_index(addr); 154 /* the pgt_lock only for Xen */ 155 pgt_lock = &pgd_page_get_mm(page)->page_table_lock; 156 spin_lock(pgt_lock); 157 158 if (!pgd_none(*pgd_ref) && !pgd_none(*pgd)) 159 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref)); 160 161 if (pgd_none(*pgd)) 162 set_pgd(pgd, *pgd_ref); 163 164 spin_unlock(pgt_lock); 165 } 166 spin_unlock(&pgd_lock); 167 } 168} 169 170static void sync_global_pgds_l4(unsigned long start, unsigned long end) 171{ 172 unsigned long addr; 173 174 for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 175 pgd_t *pgd_ref = pgd_offset_k(addr); 176 const p4d_t *p4d_ref; 177 struct page *page; 178 179 /* 180 * With folded p4d, pgd_none() is always false, we need to 181 * handle synchronization on p4d level. 182 */ 183 MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref)); 184 p4d_ref = p4d_offset(pgd_ref, addr); 185 186 if (p4d_none(*p4d_ref)) 187 continue; 188 189 spin_lock(&pgd_lock); 190 list_for_each_entry(page, &pgd_list, lru) { 191 pgd_t *pgd; 192 p4d_t *p4d; 193 spinlock_t *pgt_lock; 194 195 pgd = (pgd_t *)page_address(page) + pgd_index(addr); 196 p4d = p4d_offset(pgd, addr); 197 /* the pgt_lock only for Xen */ 198 pgt_lock = &pgd_page_get_mm(page)->page_table_lock; 199 spin_lock(pgt_lock); 200 201 if (!p4d_none(*p4d_ref) && !p4d_none(*p4d)) 202 BUG_ON(p4d_pgtable(*p4d) 203 != p4d_pgtable(*p4d_ref)); 204 205 if (p4d_none(*p4d)) 206 set_p4d(p4d, *p4d_ref); 207 208 spin_unlock(pgt_lock); 209 } 210 spin_unlock(&pgd_lock); 211 } 212} 213 214/* 215 * When memory was added make sure all the processes MM have 216 * suitable PGD entries in the local PGD level page. 217 */ 218static void sync_global_pgds(unsigned long start, unsigned long end) 219{ 220 if (pgtable_l5_enabled()) 221 sync_global_pgds_l5(start, end); 222 else 223 sync_global_pgds_l4(start, end); 224} 225 226/* 227 * NOTE: This function is marked __ref because it calls __init function 228 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0. 229 */ 230static __ref void *spp_getpage(void) 231{ 232 void *ptr; 233 234 if (after_bootmem) 235 ptr = (void *) get_zeroed_page(GFP_ATOMIC); 236 else 237 ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE); 238 239 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) { 240 panic("set_pte_phys: cannot allocate page data %s\n", 241 after_bootmem ? "after bootmem" : ""); 242 } 243 244 pr_debug("spp_getpage %p\n", ptr); 245 246 return ptr; 247} 248 249static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr) 250{ 251 if (pgd_none(*pgd)) { 252 p4d_t *p4d = (p4d_t *)spp_getpage(); 253 pgd_populate(&init_mm, pgd, p4d); 254 if (p4d != p4d_offset(pgd, 0)) 255 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n", 256 p4d, p4d_offset(pgd, 0)); 257 } 258 return p4d_offset(pgd, vaddr); 259} 260 261static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr) 262{ 263 if (p4d_none(*p4d)) { 264 pud_t *pud = (pud_t *)spp_getpage(); 265 p4d_populate(&init_mm, p4d, pud); 266 if (pud != pud_offset(p4d, 0)) 267 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n", 268 pud, pud_offset(p4d, 0)); 269 } 270 return pud_offset(p4d, vaddr); 271} 272 273static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr) 274{ 275 if (pud_none(*pud)) { 276 pmd_t *pmd = (pmd_t *) spp_getpage(); 277 pud_populate(&init_mm, pud, pmd); 278 if (pmd != pmd_offset(pud, 0)) 279 printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n", 280 pmd, pmd_offset(pud, 0)); 281 } 282 return pmd_offset(pud, vaddr); 283} 284 285static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr) 286{ 287 if (pmd_none(*pmd)) { 288 pte_t *pte = (pte_t *) spp_getpage(); 289 pmd_populate_kernel(&init_mm, pmd, pte); 290 if (pte != pte_offset_kernel(pmd, 0)) 291 printk(KERN_ERR "PAGETABLE BUG #03!\n"); 292 } 293 return pte_offset_kernel(pmd, vaddr); 294} 295 296static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte) 297{ 298 pmd_t *pmd = fill_pmd(pud, vaddr); 299 pte_t *pte = fill_pte(pmd, vaddr); 300 301 set_pte(pte, new_pte); 302 303 /* 304 * It's enough to flush this one mapping. 305 * (PGE mappings get flushed as well) 306 */ 307 flush_tlb_one_kernel(vaddr); 308} 309 310void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte) 311{ 312 p4d_t *p4d = p4d_page + p4d_index(vaddr); 313 pud_t *pud = fill_pud(p4d, vaddr); 314 315 __set_pte_vaddr(pud, vaddr, new_pte); 316} 317 318void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte) 319{ 320 pud_t *pud = pud_page + pud_index(vaddr); 321 322 __set_pte_vaddr(pud, vaddr, new_pte); 323} 324 325void set_pte_vaddr(unsigned long vaddr, pte_t pteval) 326{ 327 pgd_t *pgd; 328 p4d_t *p4d_page; 329 330 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval)); 331 332 pgd = pgd_offset_k(vaddr); 333 if (pgd_none(*pgd)) { 334 printk(KERN_ERR 335 "PGD FIXMAP MISSING, it should be setup in head.S!\n"); 336 return; 337 } 338 339 p4d_page = p4d_offset(pgd, 0); 340 set_pte_vaddr_p4d(p4d_page, vaddr, pteval); 341} 342 343pmd_t * __init populate_extra_pmd(unsigned long vaddr) 344{ 345 pgd_t *pgd; 346 p4d_t *p4d; 347 pud_t *pud; 348 349 pgd = pgd_offset_k(vaddr); 350 p4d = fill_p4d(pgd, vaddr); 351 pud = fill_pud(p4d, vaddr); 352 return fill_pmd(pud, vaddr); 353} 354 355pte_t * __init populate_extra_pte(unsigned long vaddr) 356{ 357 pmd_t *pmd; 358 359 pmd = populate_extra_pmd(vaddr); 360 return fill_pte(pmd, vaddr); 361} 362 363/* 364 * Create large page table mappings for a range of physical addresses. 365 */ 366static void __init __init_extra_mapping(unsigned long phys, unsigned long size, 367 enum page_cache_mode cache) 368{ 369 pgd_t *pgd; 370 p4d_t *p4d; 371 pud_t *pud; 372 pmd_t *pmd; 373 pgprot_t prot; 374 375 pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) | 376 protval_4k_2_large(cachemode2protval(cache)); 377 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK)); 378 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) { 379 pgd = pgd_offset_k((unsigned long)__va(phys)); 380 if (pgd_none(*pgd)) { 381 p4d = (p4d_t *) spp_getpage(); 382 set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE | 383 _PAGE_USER)); 384 } 385 p4d = p4d_offset(pgd, (unsigned long)__va(phys)); 386 if (p4d_none(*p4d)) { 387 pud = (pud_t *) spp_getpage(); 388 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE | 389 _PAGE_USER)); 390 } 391 pud = pud_offset(p4d, (unsigned long)__va(phys)); 392 if (pud_none(*pud)) { 393 pmd = (pmd_t *) spp_getpage(); 394 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | 395 _PAGE_USER)); 396 } 397 pmd = pmd_offset(pud, phys); 398 BUG_ON(!pmd_none(*pmd)); 399 set_pmd(pmd, __pmd(phys | pgprot_val(prot))); 400 } 401} 402 403void __init init_extra_mapping_wb(unsigned long phys, unsigned long size) 404{ 405 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB); 406} 407 408void __init init_extra_mapping_uc(unsigned long phys, unsigned long size) 409{ 410 __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC); 411} 412 413/* 414 * The head.S code sets up the kernel high mapping: 415 * 416 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text) 417 * 418 * phys_base holds the negative offset to the kernel, which is added 419 * to the compile time generated pmds. This results in invalid pmds up 420 * to the point where we hit the physaddr 0 mapping. 421 * 422 * We limit the mappings to the region from _text to _brk_end. _brk_end 423 * is rounded up to the 2MB boundary. This catches the invalid pmds as 424 * well, as they are located before _text: 425 */ 426void __init cleanup_highmap(void) 427{ 428 unsigned long vaddr = __START_KERNEL_map; 429 unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE; 430 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1; 431 pmd_t *pmd = level2_kernel_pgt; 432 433 /* 434 * Native path, max_pfn_mapped is not set yet. 435 * Xen has valid max_pfn_mapped set in 436 * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable(). 437 */ 438 if (max_pfn_mapped) 439 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT); 440 441 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) { 442 if (pmd_none(*pmd)) 443 continue; 444 if (vaddr < (unsigned long) _text || vaddr > end) 445 set_pmd(pmd, __pmd(0)); 446 } 447} 448 449/* 450 * Create PTE level page table mapping for physical addresses. 451 * It returns the last physical address mapped. 452 */ 453static unsigned long __meminit 454phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end, 455 pgprot_t prot, bool init) 456{ 457 unsigned long pages = 0, paddr_next; 458 unsigned long paddr_last = paddr_end; 459 pte_t *pte; 460 int i; 461 462 pte = pte_page + pte_index(paddr); 463 i = pte_index(paddr); 464 465 for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) { 466 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE; 467 if (paddr >= paddr_end) { 468 if (!after_bootmem && 469 !e820__mapped_any(paddr & PAGE_MASK, paddr_next, 470 E820_TYPE_RAM) && 471 !e820__mapped_any(paddr & PAGE_MASK, paddr_next, 472 E820_TYPE_RESERVED_KERN)) 473 set_pte_init(pte, __pte(0), init); 474 continue; 475 } 476 477 /* 478 * We will re-use the existing mapping. 479 * Xen for example has some special requirements, like mapping 480 * pagetable pages as RO. So assume someone who pre-setup 481 * these mappings are more intelligent. 482 */ 483 if (!pte_none(*pte)) { 484 if (!after_bootmem) 485 pages++; 486 continue; 487 } 488 489 if (0) 490 pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr, 491 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte); 492 pages++; 493 set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init); 494 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE; 495 } 496 497 update_page_count(PG_LEVEL_4K, pages); 498 499 return paddr_last; 500} 501 502/* 503 * Create PMD level page table mapping for physical addresses. The virtual 504 * and physical address have to be aligned at this level. 505 * It returns the last physical address mapped. 506 */ 507static unsigned long __meminit 508phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end, 509 unsigned long page_size_mask, pgprot_t prot, bool init) 510{ 511 unsigned long pages = 0, paddr_next; 512 unsigned long paddr_last = paddr_end; 513 514 int i = pmd_index(paddr); 515 516 for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) { 517 pmd_t *pmd = pmd_page + pmd_index(paddr); 518 pte_t *pte; 519 pgprot_t new_prot = prot; 520 521 paddr_next = (paddr & PMD_MASK) + PMD_SIZE; 522 if (paddr >= paddr_end) { 523 if (!after_bootmem && 524 !e820__mapped_any(paddr & PMD_MASK, paddr_next, 525 E820_TYPE_RAM) && 526 !e820__mapped_any(paddr & PMD_MASK, paddr_next, 527 E820_TYPE_RESERVED_KERN)) 528 set_pmd_init(pmd, __pmd(0), init); 529 continue; 530 } 531 532 if (!pmd_none(*pmd)) { 533 if (!pmd_leaf(*pmd)) { 534 spin_lock(&init_mm.page_table_lock); 535 pte = (pte_t *)pmd_page_vaddr(*pmd); 536 paddr_last = phys_pte_init(pte, paddr, 537 paddr_end, prot, 538 init); 539 spin_unlock(&init_mm.page_table_lock); 540 continue; 541 } 542 /* 543 * If we are ok with PG_LEVEL_2M mapping, then we will 544 * use the existing mapping, 545 * 546 * Otherwise, we will split the large page mapping but 547 * use the same existing protection bits except for 548 * large page, so that we don't violate Intel's TLB 549 * Application note (317080) which says, while changing 550 * the page sizes, new and old translations should 551 * not differ with respect to page frame and 552 * attributes. 553 */ 554 if (page_size_mask & (1 << PG_LEVEL_2M)) { 555 if (!after_bootmem) 556 pages++; 557 paddr_last = paddr_next; 558 continue; 559 } 560 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd)); 561 } 562 563 if (page_size_mask & (1<<PG_LEVEL_2M)) { 564 pages++; 565 spin_lock(&init_mm.page_table_lock); 566 set_pmd_init(pmd, 567 pfn_pmd(paddr >> PAGE_SHIFT, prot_sethuge(prot)), 568 init); 569 spin_unlock(&init_mm.page_table_lock); 570 paddr_last = paddr_next; 571 continue; 572 } 573 574 pte = alloc_low_page(); 575 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init); 576 577 spin_lock(&init_mm.page_table_lock); 578 pmd_populate_kernel_init(&init_mm, pmd, pte, init); 579 spin_unlock(&init_mm.page_table_lock); 580 } 581 update_page_count(PG_LEVEL_2M, pages); 582 return paddr_last; 583} 584 585/* 586 * Create PUD level page table mapping for physical addresses. The virtual 587 * and physical address do not have to be aligned at this level. KASLR can 588 * randomize virtual addresses up to this level. 589 * It returns the last physical address mapped. 590 */ 591static unsigned long __meminit 592phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end, 593 unsigned long page_size_mask, pgprot_t _prot, bool init) 594{ 595 unsigned long pages = 0, paddr_next; 596 unsigned long paddr_last = paddr_end; 597 unsigned long vaddr = (unsigned long)__va(paddr); 598 int i = pud_index(vaddr); 599 600 for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) { 601 pud_t *pud; 602 pmd_t *pmd; 603 pgprot_t prot = _prot; 604 605 vaddr = (unsigned long)__va(paddr); 606 pud = pud_page + pud_index(vaddr); 607 paddr_next = (paddr & PUD_MASK) + PUD_SIZE; 608 609 if (paddr >= paddr_end) { 610 if (!after_bootmem && 611 !e820__mapped_any(paddr & PUD_MASK, paddr_next, 612 E820_TYPE_RAM) && 613 !e820__mapped_any(paddr & PUD_MASK, paddr_next, 614 E820_TYPE_RESERVED_KERN)) 615 set_pud_init(pud, __pud(0), init); 616 continue; 617 } 618 619 if (!pud_none(*pud)) { 620 if (!pud_leaf(*pud)) { 621 pmd = pmd_offset(pud, 0); 622 paddr_last = phys_pmd_init(pmd, paddr, 623 paddr_end, 624 page_size_mask, 625 prot, init); 626 continue; 627 } 628 /* 629 * If we are ok with PG_LEVEL_1G mapping, then we will 630 * use the existing mapping. 631 * 632 * Otherwise, we will split the gbpage mapping but use 633 * the same existing protection bits except for large 634 * page, so that we don't violate Intel's TLB 635 * Application note (317080) which says, while changing 636 * the page sizes, new and old translations should 637 * not differ with respect to page frame and 638 * attributes. 639 */ 640 if (page_size_mask & (1 << PG_LEVEL_1G)) { 641 if (!after_bootmem) 642 pages++; 643 paddr_last = paddr_next; 644 continue; 645 } 646 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud)); 647 } 648 649 if (page_size_mask & (1<<PG_LEVEL_1G)) { 650 pages++; 651 spin_lock(&init_mm.page_table_lock); 652 set_pud_init(pud, 653 pfn_pud(paddr >> PAGE_SHIFT, prot_sethuge(prot)), 654 init); 655 spin_unlock(&init_mm.page_table_lock); 656 paddr_last = paddr_next; 657 continue; 658 } 659 660 pmd = alloc_low_page(); 661 paddr_last = phys_pmd_init(pmd, paddr, paddr_end, 662 page_size_mask, prot, init); 663 664 spin_lock(&init_mm.page_table_lock); 665 pud_populate_init(&init_mm, pud, pmd, init); 666 spin_unlock(&init_mm.page_table_lock); 667 } 668 669 update_page_count(PG_LEVEL_1G, pages); 670 671 return paddr_last; 672} 673 674static unsigned long __meminit 675phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end, 676 unsigned long page_size_mask, pgprot_t prot, bool init) 677{ 678 unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last; 679 680 paddr_last = paddr_end; 681 vaddr = (unsigned long)__va(paddr); 682 vaddr_end = (unsigned long)__va(paddr_end); 683 684 if (!pgtable_l5_enabled()) 685 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end, 686 page_size_mask, prot, init); 687 688 for (; vaddr < vaddr_end; vaddr = vaddr_next) { 689 p4d_t *p4d = p4d_page + p4d_index(vaddr); 690 pud_t *pud; 691 692 vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE; 693 paddr = __pa(vaddr); 694 695 if (paddr >= paddr_end) { 696 paddr_next = __pa(vaddr_next); 697 if (!after_bootmem && 698 !e820__mapped_any(paddr & P4D_MASK, paddr_next, 699 E820_TYPE_RAM) && 700 !e820__mapped_any(paddr & P4D_MASK, paddr_next, 701 E820_TYPE_RESERVED_KERN)) 702 set_p4d_init(p4d, __p4d(0), init); 703 continue; 704 } 705 706 if (!p4d_none(*p4d)) { 707 pud = pud_offset(p4d, 0); 708 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end), 709 page_size_mask, prot, init); 710 continue; 711 } 712 713 pud = alloc_low_page(); 714 paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end), 715 page_size_mask, prot, init); 716 717 spin_lock(&init_mm.page_table_lock); 718 p4d_populate_init(&init_mm, p4d, pud, init); 719 spin_unlock(&init_mm.page_table_lock); 720 } 721 722 return paddr_last; 723} 724 725static unsigned long __meminit 726__kernel_physical_mapping_init(unsigned long paddr_start, 727 unsigned long paddr_end, 728 unsigned long page_size_mask, 729 pgprot_t prot, bool init) 730{ 731 bool pgd_changed = false; 732 unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last; 733 734 paddr_last = paddr_end; 735 vaddr = (unsigned long)__va(paddr_start); 736 vaddr_end = (unsigned long)__va(paddr_end); 737 vaddr_start = vaddr; 738 739 for (; vaddr < vaddr_end; vaddr = vaddr_next) { 740 pgd_t *pgd = pgd_offset_k(vaddr); 741 p4d_t *p4d; 742 743 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE; 744 745 if (pgd_val(*pgd)) { 746 p4d = (p4d_t *)pgd_page_vaddr(*pgd); 747 paddr_last = phys_p4d_init(p4d, __pa(vaddr), 748 __pa(vaddr_end), 749 page_size_mask, 750 prot, init); 751 continue; 752 } 753 754 p4d = alloc_low_page(); 755 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end), 756 page_size_mask, prot, init); 757 758 spin_lock(&init_mm.page_table_lock); 759 if (pgtable_l5_enabled()) 760 pgd_populate_init(&init_mm, pgd, p4d, init); 761 else 762 p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr), 763 (pud_t *) p4d, init); 764 765 spin_unlock(&init_mm.page_table_lock); 766 pgd_changed = true; 767 } 768 769 if (pgd_changed) 770 sync_global_pgds(vaddr_start, vaddr_end - 1); 771 772 return paddr_last; 773} 774 775 776/* 777 * Create page table mapping for the physical memory for specific physical 778 * addresses. Note that it can only be used to populate non-present entries. 779 * The virtual and physical addresses have to be aligned on PMD level 780 * down. It returns the last physical address mapped. 781 */ 782unsigned long __meminit 783kernel_physical_mapping_init(unsigned long paddr_start, 784 unsigned long paddr_end, 785 unsigned long page_size_mask, pgprot_t prot) 786{ 787 return __kernel_physical_mapping_init(paddr_start, paddr_end, 788 page_size_mask, prot, true); 789} 790 791/* 792 * This function is similar to kernel_physical_mapping_init() above with the 793 * exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe() 794 * when updating the mapping. The caller is responsible to flush the TLBs after 795 * the function returns. 796 */ 797unsigned long __meminit 798kernel_physical_mapping_change(unsigned long paddr_start, 799 unsigned long paddr_end, 800 unsigned long page_size_mask) 801{ 802 return __kernel_physical_mapping_init(paddr_start, paddr_end, 803 page_size_mask, PAGE_KERNEL, 804 false); 805} 806 807#ifndef CONFIG_NUMA 808void __init initmem_init(void) 809{ 810 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); 811} 812#endif 813 814void __init paging_init(void) 815{ 816 sparse_init(); 817 818 /* 819 * clear the default setting with node 0 820 * note: don't use nodes_clear here, that is really clearing when 821 * numa support is not compiled in, and later node_set_state 822 * will not set it back. 823 */ 824 node_clear_state(0, N_MEMORY); 825 node_clear_state(0, N_NORMAL_MEMORY); 826 827 zone_sizes_init(); 828} 829 830#ifdef CONFIG_SPARSEMEM_VMEMMAP 831#define PAGE_UNUSED 0xFD 832 833/* 834 * The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges 835 * from unused_pmd_start to next PMD_SIZE boundary. 836 */ 837static unsigned long unused_pmd_start __meminitdata; 838 839static void __meminit vmemmap_flush_unused_pmd(void) 840{ 841 if (!unused_pmd_start) 842 return; 843 /* 844 * Clears (unused_pmd_start, PMD_END] 845 */ 846 memset((void *)unused_pmd_start, PAGE_UNUSED, 847 ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start); 848 unused_pmd_start = 0; 849} 850 851#ifdef CONFIG_MEMORY_HOTPLUG 852/* Returns true if the PMD is completely unused and thus it can be freed */ 853static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end) 854{ 855 unsigned long start = ALIGN_DOWN(addr, PMD_SIZE); 856 857 /* 858 * Flush the unused range cache to ensure that memchr_inv() will work 859 * for the whole range. 860 */ 861 vmemmap_flush_unused_pmd(); 862 memset((void *)addr, PAGE_UNUSED, end - addr); 863 864 return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE); 865} 866#endif 867 868static void __meminit __vmemmap_use_sub_pmd(unsigned long start) 869{ 870 /* 871 * As we expect to add in the same granularity as we remove, it's 872 * sufficient to mark only some piece used to block the memmap page from 873 * getting removed when removing some other adjacent memmap (just in 874 * case the first memmap never gets initialized e.g., because the memory 875 * block never gets onlined). 876 */ 877 memset((void *)start, 0, sizeof(struct page)); 878} 879 880static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end) 881{ 882 /* 883 * We only optimize if the new used range directly follows the 884 * previously unused range (esp., when populating consecutive sections). 885 */ 886 if (unused_pmd_start == start) { 887 if (likely(IS_ALIGNED(end, PMD_SIZE))) 888 unused_pmd_start = 0; 889 else 890 unused_pmd_start = end; 891 return; 892 } 893 894 /* 895 * If the range does not contiguously follows previous one, make sure 896 * to mark the unused range of the previous one so it can be removed. 897 */ 898 vmemmap_flush_unused_pmd(); 899 __vmemmap_use_sub_pmd(start); 900} 901 902 903static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end) 904{ 905 const unsigned long page = ALIGN_DOWN(start, PMD_SIZE); 906 907 vmemmap_flush_unused_pmd(); 908 909 /* 910 * Could be our memmap page is filled with PAGE_UNUSED already from a 911 * previous remove. Make sure to reset it. 912 */ 913 __vmemmap_use_sub_pmd(start); 914 915 /* 916 * Mark with PAGE_UNUSED the unused parts of the new memmap range 917 */ 918 if (!IS_ALIGNED(start, PMD_SIZE)) 919 memset((void *)page, PAGE_UNUSED, start - page); 920 921 /* 922 * We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of 923 * consecutive sections. Remember for the last added PMD where the 924 * unused range begins. 925 */ 926 if (!IS_ALIGNED(end, PMD_SIZE)) 927 unused_pmd_start = end; 928} 929#endif 930 931/* 932 * Memory hotplug specific functions 933 */ 934#ifdef CONFIG_MEMORY_HOTPLUG 935/* 936 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need 937 * updating. 938 */ 939static void update_end_of_memory_vars(u64 start, u64 size) 940{ 941 unsigned long end_pfn = PFN_UP(start + size); 942 943 if (end_pfn > max_pfn) { 944 max_pfn = end_pfn; 945 max_low_pfn = end_pfn; 946 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; 947 } 948} 949 950int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 951 struct mhp_params *params) 952{ 953 int ret; 954 955 ret = __add_pages(nid, start_pfn, nr_pages, params); 956 WARN_ON_ONCE(ret); 957 958 /* update max_pfn, max_low_pfn and high_memory */ 959 update_end_of_memory_vars(start_pfn << PAGE_SHIFT, 960 nr_pages << PAGE_SHIFT); 961 962 return ret; 963} 964 965int arch_add_memory(int nid, u64 start, u64 size, 966 struct mhp_params *params) 967{ 968 unsigned long start_pfn = start >> PAGE_SHIFT; 969 unsigned long nr_pages = size >> PAGE_SHIFT; 970 971 init_memory_mapping(start, start + size, params->pgprot); 972 973 return add_pages(nid, start_pfn, nr_pages, params); 974} 975 976static void __meminit free_pagetable(struct page *page, int order) 977{ 978 unsigned long magic; 979 unsigned int nr_pages = 1 << order; 980 981 /* bootmem page has reserved flag */ 982 if (PageReserved(page)) { 983 __ClearPageReserved(page); 984 985 magic = page->index; 986 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) { 987 while (nr_pages--) 988 put_page_bootmem(page++); 989 } else 990 while (nr_pages--) 991 free_reserved_page(page++); 992 } else 993 free_pages((unsigned long)page_address(page), order); 994} 995 996static void __meminit free_hugepage_table(struct page *page, 997 struct vmem_altmap *altmap) 998{ 999 if (altmap) 1000 vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE); 1001 else 1002 free_pagetable(page, get_order(PMD_SIZE)); 1003} 1004 1005static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd) 1006{ 1007 pte_t *pte; 1008 int i; 1009 1010 for (i = 0; i < PTRS_PER_PTE; i++) { 1011 pte = pte_start + i; 1012 if (!pte_none(*pte)) 1013 return; 1014 } 1015 1016 /* free a pte table */ 1017 free_pagetable(pmd_page(*pmd), 0); 1018 spin_lock(&init_mm.page_table_lock); 1019 pmd_clear(pmd); 1020 spin_unlock(&init_mm.page_table_lock); 1021} 1022 1023static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud) 1024{ 1025 pmd_t *pmd; 1026 int i; 1027 1028 for (i = 0; i < PTRS_PER_PMD; i++) { 1029 pmd = pmd_start + i; 1030 if (!pmd_none(*pmd)) 1031 return; 1032 } 1033 1034 /* free a pmd table */ 1035 free_pagetable(pud_page(*pud), 0); 1036 spin_lock(&init_mm.page_table_lock); 1037 pud_clear(pud); 1038 spin_unlock(&init_mm.page_table_lock); 1039} 1040 1041static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d) 1042{ 1043 pud_t *pud; 1044 int i; 1045 1046 for (i = 0; i < PTRS_PER_PUD; i++) { 1047 pud = pud_start + i; 1048 if (!pud_none(*pud)) 1049 return; 1050 } 1051 1052 /* free a pud table */ 1053 free_pagetable(p4d_page(*p4d), 0); 1054 spin_lock(&init_mm.page_table_lock); 1055 p4d_clear(p4d); 1056 spin_unlock(&init_mm.page_table_lock); 1057} 1058 1059static void __meminit 1060remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end, 1061 bool direct) 1062{ 1063 unsigned long next, pages = 0; 1064 pte_t *pte; 1065 phys_addr_t phys_addr; 1066 1067 pte = pte_start + pte_index(addr); 1068 for (; addr < end; addr = next, pte++) { 1069 next = (addr + PAGE_SIZE) & PAGE_MASK; 1070 if (next > end) 1071 next = end; 1072 1073 if (!pte_present(*pte)) 1074 continue; 1075 1076 /* 1077 * We mapped [0,1G) memory as identity mapping when 1078 * initializing, in arch/x86/kernel/head_64.S. These 1079 * pagetables cannot be removed. 1080 */ 1081 phys_addr = pte_val(*pte) + (addr & PAGE_MASK); 1082 if (phys_addr < (phys_addr_t)0x40000000) 1083 return; 1084 1085 if (!direct) 1086 free_pagetable(pte_page(*pte), 0); 1087 1088 spin_lock(&init_mm.page_table_lock); 1089 pte_clear(&init_mm, addr, pte); 1090 spin_unlock(&init_mm.page_table_lock); 1091 1092 /* For non-direct mapping, pages means nothing. */ 1093 pages++; 1094 } 1095 1096 /* Call free_pte_table() in remove_pmd_table(). */ 1097 flush_tlb_all(); 1098 if (direct) 1099 update_page_count(PG_LEVEL_4K, -pages); 1100} 1101 1102static void __meminit 1103remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end, 1104 bool direct, struct vmem_altmap *altmap) 1105{ 1106 unsigned long next, pages = 0; 1107 pte_t *pte_base; 1108 pmd_t *pmd; 1109 1110 pmd = pmd_start + pmd_index(addr); 1111 for (; addr < end; addr = next, pmd++) { 1112 next = pmd_addr_end(addr, end); 1113 1114 if (!pmd_present(*pmd)) 1115 continue; 1116 1117 if (pmd_leaf(*pmd)) { 1118 if (IS_ALIGNED(addr, PMD_SIZE) && 1119 IS_ALIGNED(next, PMD_SIZE)) { 1120 if (!direct) 1121 free_hugepage_table(pmd_page(*pmd), 1122 altmap); 1123 1124 spin_lock(&init_mm.page_table_lock); 1125 pmd_clear(pmd); 1126 spin_unlock(&init_mm.page_table_lock); 1127 pages++; 1128 } 1129#ifdef CONFIG_SPARSEMEM_VMEMMAP 1130 else if (vmemmap_pmd_is_unused(addr, next)) { 1131 free_hugepage_table(pmd_page(*pmd), 1132 altmap); 1133 spin_lock(&init_mm.page_table_lock); 1134 pmd_clear(pmd); 1135 spin_unlock(&init_mm.page_table_lock); 1136 } 1137#endif 1138 continue; 1139 } 1140 1141 pte_base = (pte_t *)pmd_page_vaddr(*pmd); 1142 remove_pte_table(pte_base, addr, next, direct); 1143 free_pte_table(pte_base, pmd); 1144 } 1145 1146 /* Call free_pmd_table() in remove_pud_table(). */ 1147 if (direct) 1148 update_page_count(PG_LEVEL_2M, -pages); 1149} 1150 1151static void __meminit 1152remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end, 1153 struct vmem_altmap *altmap, bool direct) 1154{ 1155 unsigned long next, pages = 0; 1156 pmd_t *pmd_base; 1157 pud_t *pud; 1158 1159 pud = pud_start + pud_index(addr); 1160 for (; addr < end; addr = next, pud++) { 1161 next = pud_addr_end(addr, end); 1162 1163 if (!pud_present(*pud)) 1164 continue; 1165 1166 if (pud_leaf(*pud) && 1167 IS_ALIGNED(addr, PUD_SIZE) && 1168 IS_ALIGNED(next, PUD_SIZE)) { 1169 spin_lock(&init_mm.page_table_lock); 1170 pud_clear(pud); 1171 spin_unlock(&init_mm.page_table_lock); 1172 pages++; 1173 continue; 1174 } 1175 1176 pmd_base = pmd_offset(pud, 0); 1177 remove_pmd_table(pmd_base, addr, next, direct, altmap); 1178 free_pmd_table(pmd_base, pud); 1179 } 1180 1181 if (direct) 1182 update_page_count(PG_LEVEL_1G, -pages); 1183} 1184 1185static void __meminit 1186remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end, 1187 struct vmem_altmap *altmap, bool direct) 1188{ 1189 unsigned long next, pages = 0; 1190 pud_t *pud_base; 1191 p4d_t *p4d; 1192 1193 p4d = p4d_start + p4d_index(addr); 1194 for (; addr < end; addr = next, p4d++) { 1195 next = p4d_addr_end(addr, end); 1196 1197 if (!p4d_present(*p4d)) 1198 continue; 1199 1200 BUILD_BUG_ON(p4d_leaf(*p4d)); 1201 1202 pud_base = pud_offset(p4d, 0); 1203 remove_pud_table(pud_base, addr, next, altmap, direct); 1204 /* 1205 * For 4-level page tables we do not want to free PUDs, but in the 1206 * 5-level case we should free them. This code will have to change 1207 * to adapt for boot-time switching between 4 and 5 level page tables. 1208 */ 1209 if (pgtable_l5_enabled()) 1210 free_pud_table(pud_base, p4d); 1211 } 1212 1213 if (direct) 1214 update_page_count(PG_LEVEL_512G, -pages); 1215} 1216 1217/* start and end are both virtual address. */ 1218static void __meminit 1219remove_pagetable(unsigned long start, unsigned long end, bool direct, 1220 struct vmem_altmap *altmap) 1221{ 1222 unsigned long next; 1223 unsigned long addr; 1224 pgd_t *pgd; 1225 p4d_t *p4d; 1226 1227 for (addr = start; addr < end; addr = next) { 1228 next = pgd_addr_end(addr, end); 1229 1230 pgd = pgd_offset_k(addr); 1231 if (!pgd_present(*pgd)) 1232 continue; 1233 1234 p4d = p4d_offset(pgd, 0); 1235 remove_p4d_table(p4d, addr, next, altmap, direct); 1236 } 1237 1238 flush_tlb_all(); 1239} 1240 1241void __ref vmemmap_free(unsigned long start, unsigned long end, 1242 struct vmem_altmap *altmap) 1243{ 1244 VM_BUG_ON(!PAGE_ALIGNED(start)); 1245 VM_BUG_ON(!PAGE_ALIGNED(end)); 1246 1247 remove_pagetable(start, end, false, altmap); 1248} 1249 1250static void __meminit 1251kernel_physical_mapping_remove(unsigned long start, unsigned long end) 1252{ 1253 start = (unsigned long)__va(start); 1254 end = (unsigned long)__va(end); 1255 1256 remove_pagetable(start, end, true, NULL); 1257} 1258 1259void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 1260{ 1261 unsigned long start_pfn = start >> PAGE_SHIFT; 1262 unsigned long nr_pages = size >> PAGE_SHIFT; 1263 1264 __remove_pages(start_pfn, nr_pages, altmap); 1265 kernel_physical_mapping_remove(start, start + size); 1266} 1267#endif /* CONFIG_MEMORY_HOTPLUG */ 1268 1269static struct kcore_list kcore_vsyscall; 1270 1271static void __init register_page_bootmem_info(void) 1272{ 1273#if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP) 1274 int i; 1275 1276 for_each_online_node(i) 1277 register_page_bootmem_info_node(NODE_DATA(i)); 1278#endif 1279} 1280 1281/* 1282 * Pre-allocates page-table pages for the vmalloc area in the kernel page-table. 1283 * Only the level which needs to be synchronized between all page-tables is 1284 * allocated because the synchronization can be expensive. 1285 */ 1286static void __init preallocate_vmalloc_pages(void) 1287{ 1288 unsigned long addr; 1289 const char *lvl; 1290 1291 for (addr = VMALLOC_START; addr <= VMEMORY_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 1292 pgd_t *pgd = pgd_offset_k(addr); 1293 p4d_t *p4d; 1294 pud_t *pud; 1295 1296 lvl = "p4d"; 1297 p4d = p4d_alloc(&init_mm, pgd, addr); 1298 if (!p4d) 1299 goto failed; 1300 1301 if (pgtable_l5_enabled()) 1302 continue; 1303 1304 /* 1305 * The goal here is to allocate all possibly required 1306 * hardware page tables pointed to by the top hardware 1307 * level. 1308 * 1309 * On 4-level systems, the P4D layer is folded away and 1310 * the above code does no preallocation. Below, go down 1311 * to the pud _software_ level to ensure the second 1312 * hardware level is allocated on 4-level systems too. 1313 */ 1314 lvl = "pud"; 1315 pud = pud_alloc(&init_mm, p4d, addr); 1316 if (!pud) 1317 goto failed; 1318 } 1319 1320 return; 1321 1322failed: 1323 1324 /* 1325 * The pages have to be there now or they will be missing in 1326 * process page-tables later. 1327 */ 1328 panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl); 1329} 1330 1331void __init mem_init(void) 1332{ 1333 pci_iommu_alloc(); 1334 1335 /* clear_bss() already clear the empty_zero_page */ 1336 1337 /* this will put all memory onto the freelists */ 1338 memblock_free_all(); 1339 after_bootmem = 1; 1340 x86_init.hyper.init_after_bootmem(); 1341 1342 /* 1343 * Must be done after boot memory is put on freelist, because here we 1344 * might set fields in deferred struct pages that have not yet been 1345 * initialized, and memblock_free_all() initializes all the reserved 1346 * deferred pages for us. 1347 */ 1348 register_page_bootmem_info(); 1349 1350 /* Register memory areas for /proc/kcore */ 1351 if (get_gate_vma(&init_mm)) 1352 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER); 1353 1354 preallocate_vmalloc_pages(); 1355} 1356 1357#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 1358int __init deferred_page_init_max_threads(const struct cpumask *node_cpumask) 1359{ 1360 /* 1361 * More CPUs always led to greater speedups on tested systems, up to 1362 * all the nodes' CPUs. Use all since the system is otherwise idle 1363 * now. 1364 */ 1365 return max_t(int, cpumask_weight(node_cpumask), 1); 1366} 1367#endif 1368 1369int kernel_set_to_readonly; 1370 1371void mark_rodata_ro(void) 1372{ 1373 unsigned long start = PFN_ALIGN(_text); 1374 unsigned long rodata_start = PFN_ALIGN(__start_rodata); 1375 unsigned long end = (unsigned long)__end_rodata_hpage_align; 1376 unsigned long text_end = PFN_ALIGN(_etext); 1377 unsigned long rodata_end = PFN_ALIGN(__end_rodata); 1378 unsigned long all_end; 1379 1380 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", 1381 (end - start) >> 10); 1382 set_memory_ro(start, (end - start) >> PAGE_SHIFT); 1383 1384 kernel_set_to_readonly = 1; 1385 1386 /* 1387 * The rodata/data/bss/brk section (but not the kernel text!) 1388 * should also be not-executable. 1389 * 1390 * We align all_end to PMD_SIZE because the existing mapping 1391 * is a full PMD. If we would align _brk_end to PAGE_SIZE we 1392 * split the PMD and the reminder between _brk_end and the end 1393 * of the PMD will remain mapped executable. 1394 * 1395 * Any PMD which was setup after the one which covers _brk_end 1396 * has been zapped already via cleanup_highmem(). 1397 */ 1398 all_end = roundup((unsigned long)_brk_end, PMD_SIZE); 1399 set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT); 1400 1401 set_ftrace_ops_ro(); 1402 1403#ifdef CONFIG_CPA_DEBUG 1404 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end); 1405 set_memory_rw(start, (end-start) >> PAGE_SHIFT); 1406 1407 printk(KERN_INFO "Testing CPA: again\n"); 1408 set_memory_ro(start, (end-start) >> PAGE_SHIFT); 1409#endif 1410 1411 free_kernel_image_pages("unused kernel image (text/rodata gap)", 1412 (void *)text_end, (void *)rodata_start); 1413 free_kernel_image_pages("unused kernel image (rodata/data gap)", 1414 (void *)rodata_end, (void *)_sdata); 1415} 1416 1417/* 1418 * Block size is the minimum amount of memory which can be hotplugged or 1419 * hotremoved. It must be power of two and must be equal or larger than 1420 * MIN_MEMORY_BLOCK_SIZE. 1421 */ 1422#define MAX_BLOCK_SIZE (2UL << 30) 1423 1424/* Amount of ram needed to start using large blocks */ 1425#define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30) 1426 1427/* Adjustable memory block size */ 1428static unsigned long set_memory_block_size; 1429int __init set_memory_block_size_order(unsigned int order) 1430{ 1431 unsigned long size = 1UL << order; 1432 1433 if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE) 1434 return -EINVAL; 1435 1436 set_memory_block_size = size; 1437 return 0; 1438} 1439 1440static unsigned long probe_memory_block_size(void) 1441{ 1442 unsigned long boot_mem_end = max_pfn << PAGE_SHIFT; 1443 unsigned long bz; 1444 1445 /* If memory block size has been set, then use it */ 1446 bz = set_memory_block_size; 1447 if (bz) 1448 goto done; 1449 1450 /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */ 1451 if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) { 1452 bz = MIN_MEMORY_BLOCK_SIZE; 1453 goto done; 1454 } 1455 1456 /* 1457 * Use max block size to minimize overhead on bare metal, where 1458 * alignment for memory hotplug isn't a concern. 1459 */ 1460 if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) { 1461 bz = MAX_BLOCK_SIZE; 1462 goto done; 1463 } 1464 1465 /* Find the largest allowed block size that aligns to memory end */ 1466 for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) { 1467 if (IS_ALIGNED(boot_mem_end, bz)) 1468 break; 1469 } 1470done: 1471 pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20); 1472 1473 return bz; 1474} 1475 1476static unsigned long memory_block_size_probed; 1477unsigned long memory_block_size_bytes(void) 1478{ 1479 if (!memory_block_size_probed) 1480 memory_block_size_probed = probe_memory_block_size(); 1481 1482 return memory_block_size_probed; 1483} 1484 1485#ifdef CONFIG_SPARSEMEM_VMEMMAP 1486/* 1487 * Initialise the sparsemem vmemmap using huge-pages at the PMD level. 1488 */ 1489static long __meminitdata addr_start, addr_end; 1490static void __meminitdata *p_start, *p_end; 1491static int __meminitdata node_start; 1492 1493void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node, 1494 unsigned long addr, unsigned long next) 1495{ 1496 pte_t entry; 1497 1498 entry = pfn_pte(__pa(p) >> PAGE_SHIFT, 1499 PAGE_KERNEL_LARGE); 1500 set_pmd(pmd, __pmd(pte_val(entry))); 1501 1502 /* check to see if we have contiguous blocks */ 1503 if (p_end != p || node_start != node) { 1504 if (p_start) 1505 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n", 1506 addr_start, addr_end-1, p_start, p_end-1, node_start); 1507 addr_start = addr; 1508 node_start = node; 1509 p_start = p; 1510 } 1511 1512 addr_end = addr + PMD_SIZE; 1513 p_end = p + PMD_SIZE; 1514 1515 if (!IS_ALIGNED(addr, PMD_SIZE) || 1516 !IS_ALIGNED(next, PMD_SIZE)) 1517 vmemmap_use_new_sub_pmd(addr, next); 1518} 1519 1520int __meminit vmemmap_check_pmd(pmd_t *pmd, int node, 1521 unsigned long addr, unsigned long next) 1522{ 1523 int large = pmd_leaf(*pmd); 1524 1525 if (pmd_leaf(*pmd)) { 1526 vmemmap_verify((pte_t *)pmd, node, addr, next); 1527 vmemmap_use_sub_pmd(addr, next); 1528 } 1529 1530 return large; 1531} 1532 1533int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1534 struct vmem_altmap *altmap) 1535{ 1536 int err; 1537 1538 VM_BUG_ON(!PAGE_ALIGNED(start)); 1539 VM_BUG_ON(!PAGE_ALIGNED(end)); 1540 1541 if (end - start < PAGES_PER_SECTION * sizeof(struct page)) 1542 err = vmemmap_populate_basepages(start, end, node, NULL); 1543 else if (boot_cpu_has(X86_FEATURE_PSE)) 1544 err = vmemmap_populate_hugepages(start, end, node, altmap); 1545 else if (altmap) { 1546 pr_err_once("%s: no cpu support for altmap allocations\n", 1547 __func__); 1548 err = -ENOMEM; 1549 } else 1550 err = vmemmap_populate_basepages(start, end, node, NULL); 1551 if (!err) 1552 sync_global_pgds(start, end - 1); 1553 return err; 1554} 1555 1556#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE 1557void register_page_bootmem_memmap(unsigned long section_nr, 1558 struct page *start_page, unsigned long nr_pages) 1559{ 1560 unsigned long addr = (unsigned long)start_page; 1561 unsigned long end = (unsigned long)(start_page + nr_pages); 1562 unsigned long next; 1563 pgd_t *pgd; 1564 p4d_t *p4d; 1565 pud_t *pud; 1566 pmd_t *pmd; 1567 unsigned int nr_pmd_pages; 1568 struct page *page; 1569 1570 for (; addr < end; addr = next) { 1571 pte_t *pte = NULL; 1572 1573 pgd = pgd_offset_k(addr); 1574 if (pgd_none(*pgd)) { 1575 next = (addr + PAGE_SIZE) & PAGE_MASK; 1576 continue; 1577 } 1578 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO); 1579 1580 p4d = p4d_offset(pgd, addr); 1581 if (p4d_none(*p4d)) { 1582 next = (addr + PAGE_SIZE) & PAGE_MASK; 1583 continue; 1584 } 1585 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO); 1586 1587 pud = pud_offset(p4d, addr); 1588 if (pud_none(*pud)) { 1589 next = (addr + PAGE_SIZE) & PAGE_MASK; 1590 continue; 1591 } 1592 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO); 1593 1594 if (!boot_cpu_has(X86_FEATURE_PSE)) { 1595 next = (addr + PAGE_SIZE) & PAGE_MASK; 1596 pmd = pmd_offset(pud, addr); 1597 if (pmd_none(*pmd)) 1598 continue; 1599 get_page_bootmem(section_nr, pmd_page(*pmd), 1600 MIX_SECTION_INFO); 1601 1602 pte = pte_offset_kernel(pmd, addr); 1603 if (pte_none(*pte)) 1604 continue; 1605 get_page_bootmem(section_nr, pte_page(*pte), 1606 SECTION_INFO); 1607 } else { 1608 next = pmd_addr_end(addr, end); 1609 1610 pmd = pmd_offset(pud, addr); 1611 if (pmd_none(*pmd)) 1612 continue; 1613 1614 nr_pmd_pages = 1 << get_order(PMD_SIZE); 1615 page = pmd_page(*pmd); 1616 while (nr_pmd_pages--) 1617 get_page_bootmem(section_nr, page++, 1618 SECTION_INFO); 1619 } 1620 } 1621} 1622#endif 1623 1624void __meminit vmemmap_populate_print_last(void) 1625{ 1626 if (p_start) { 1627 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n", 1628 addr_start, addr_end-1, p_start, p_end-1, node_start); 1629 p_start = NULL; 1630 p_end = NULL; 1631 node_start = 0; 1632 } 1633} 1634#endif 1635