1 /* 2 * Based on arch/arm/mm/mmu.c 3 * 4 * Copyright (C) 1995-2005 Russell King 5 * Copyright (C) 2012 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include <linux/cache.h> 21 #include <linux/export.h> 22 #include <linux/kernel.h> 23 #include <linux/errno.h> 24 #include <linux/init.h> 25 #include <linux/libfdt.h> 26 #include <linux/mman.h> 27 #include <linux/nodemask.h> 28 #include <linux/memblock.h> 29 #include <linux/fs.h> 30 #include <linux/io.h> 31 32 #include <asm/barrier.h> 33 #include <asm/cputype.h> 34 #include <asm/fixmap.h> 35 #include <asm/kasan.h> 36 #include <asm/kernel-pgtable.h> 37 #include <asm/sections.h> 38 #include <asm/setup.h> 39 #include <asm/sizes.h> 40 #include <asm/tlb.h> 41 #include <asm/memblock.h> 42 #include <asm/mmu_context.h> 43 #include <asm/ptdump.h> 44 45 u64 idmap_t0sz = TCR_T0SZ(VA_BITS); 46 47 u64 kimage_voffset __ro_after_init; 48 EXPORT_SYMBOL(kimage_voffset); 49 50 /* 51 * Empty_zero_page is a special page that is used for zero-initialized data 52 * and COW. 53 */ 54 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 55 EXPORT_SYMBOL(empty_zero_page); 56 57 static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss; 58 static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused; 59 static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused; 60 61 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 62 unsigned long size, pgprot_t vma_prot) 63 { 64 if (!pfn_valid(pfn)) 65 return pgprot_noncached(vma_prot); 66 else if (file->f_flags & O_SYNC) 67 return pgprot_writecombine(vma_prot); 68 return vma_prot; 69 } 70 EXPORT_SYMBOL(phys_mem_access_prot); 71 72 static phys_addr_t __init early_pgtable_alloc(void) 73 { 74 phys_addr_t phys; 75 void *ptr; 76 77 phys = memblock_alloc(PAGE_SIZE, PAGE_SIZE); 78 79 /* 80 * The FIX_{PGD,PUD,PMD} slots may be in active use, but the FIX_PTE 81 * slot will be free, so we can (ab)use the FIX_PTE slot to initialise 82 * any level of table. 83 */ 84 ptr = pte_set_fixmap(phys); 85 86 memset(ptr, 0, PAGE_SIZE); 87 88 /* 89 * Implicit barriers also ensure the zeroed page is visible to the page 90 * table walker 91 */ 92 pte_clear_fixmap(); 93 94 return phys; 95 } 96 97 static bool pgattr_change_is_safe(u64 old, u64 new) 98 { 99 /* 100 * The following mapping attributes may be updated in live 101 * kernel mappings without the need for break-before-make. 102 */ 103 static const pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE; 104 105 return old == 0 || new == 0 || ((old ^ new) & ~mask) == 0; 106 } 107 108 static void alloc_init_pte(pmd_t *pmd, unsigned long addr, 109 unsigned long end, unsigned long pfn, 110 pgprot_t prot, 111 phys_addr_t (*pgtable_alloc)(void), 112 bool page_mappings_only) 113 { 114 pgprot_t __prot = prot; 115 pte_t *pte; 116 117 BUG_ON(pmd_sect(*pmd)); 118 if (pmd_none(*pmd)) { 119 phys_addr_t pte_phys; 120 BUG_ON(!pgtable_alloc); 121 pte_phys = pgtable_alloc(); 122 pte = pte_set_fixmap(pte_phys); 123 __pmd_populate(pmd, pte_phys, PMD_TYPE_TABLE); 124 pte_clear_fixmap(); 125 } 126 BUG_ON(pmd_bad(*pmd)); 127 128 pte = pte_set_fixmap_offset(pmd, addr); 129 do { 130 pte_t old_pte = *pte; 131 132 /* 133 * Set the contiguous bit for the subsequent group of PTEs if 134 * its size and alignment are appropriate. 135 */ 136 if (((addr | PFN_PHYS(pfn)) & ~CONT_PTE_MASK) == 0) { 137 if (end - addr >= CONT_PTE_SIZE && !page_mappings_only) 138 __prot = __pgprot(pgprot_val(prot) | PTE_CONT); 139 else 140 __prot = prot; 141 } 142 143 set_pte(pte, pfn_pte(pfn, __prot)); 144 pfn++; 145 146 /* 147 * After the PTE entry has been populated once, we 148 * only allow updates to the permission attributes. 149 */ 150 BUG_ON(!pgattr_change_is_safe(pte_val(old_pte), pte_val(*pte))); 151 152 } while (pte++, addr += PAGE_SIZE, addr != end); 153 154 pte_clear_fixmap(); 155 } 156 157 static void alloc_init_pmd(pud_t *pud, unsigned long addr, unsigned long end, 158 phys_addr_t phys, pgprot_t prot, 159 phys_addr_t (*pgtable_alloc)(void), 160 bool page_mappings_only) 161 { 162 pgprot_t __prot = prot; 163 pmd_t *pmd; 164 unsigned long next; 165 166 /* 167 * Check for initial section mappings in the pgd/pud and remove them. 168 */ 169 BUG_ON(pud_sect(*pud)); 170 if (pud_none(*pud)) { 171 phys_addr_t pmd_phys; 172 BUG_ON(!pgtable_alloc); 173 pmd_phys = pgtable_alloc(); 174 pmd = pmd_set_fixmap(pmd_phys); 175 __pud_populate(pud, pmd_phys, PUD_TYPE_TABLE); 176 pmd_clear_fixmap(); 177 } 178 BUG_ON(pud_bad(*pud)); 179 180 pmd = pmd_set_fixmap_offset(pud, addr); 181 do { 182 pmd_t old_pmd = *pmd; 183 184 next = pmd_addr_end(addr, end); 185 186 /* try section mapping first */ 187 if (((addr | next | phys) & ~SECTION_MASK) == 0 && 188 !page_mappings_only) { 189 /* 190 * Set the contiguous bit for the subsequent group of 191 * PMDs if its size and alignment are appropriate. 192 */ 193 if (((addr | phys) & ~CONT_PMD_MASK) == 0) { 194 if (end - addr >= CONT_PMD_SIZE) 195 __prot = __pgprot(pgprot_val(prot) | 196 PTE_CONT); 197 else 198 __prot = prot; 199 } 200 pmd_set_huge(pmd, phys, __prot); 201 202 /* 203 * After the PMD entry has been populated once, we 204 * only allow updates to the permission attributes. 205 */ 206 BUG_ON(!pgattr_change_is_safe(pmd_val(old_pmd), 207 pmd_val(*pmd))); 208 } else { 209 alloc_init_pte(pmd, addr, next, __phys_to_pfn(phys), 210 prot, pgtable_alloc, 211 page_mappings_only); 212 213 BUG_ON(pmd_val(old_pmd) != 0 && 214 pmd_val(old_pmd) != pmd_val(*pmd)); 215 } 216 phys += next - addr; 217 } while (pmd++, addr = next, addr != end); 218 219 pmd_clear_fixmap(); 220 } 221 222 static inline bool use_1G_block(unsigned long addr, unsigned long next, 223 unsigned long phys) 224 { 225 if (PAGE_SHIFT != 12) 226 return false; 227 228 if (((addr | next | phys) & ~PUD_MASK) != 0) 229 return false; 230 231 return true; 232 } 233 234 static void alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end, 235 phys_addr_t phys, pgprot_t prot, 236 phys_addr_t (*pgtable_alloc)(void), 237 bool page_mappings_only) 238 { 239 pud_t *pud; 240 unsigned long next; 241 242 if (pgd_none(*pgd)) { 243 phys_addr_t pud_phys; 244 BUG_ON(!pgtable_alloc); 245 pud_phys = pgtable_alloc(); 246 __pgd_populate(pgd, pud_phys, PUD_TYPE_TABLE); 247 } 248 BUG_ON(pgd_bad(*pgd)); 249 250 pud = pud_set_fixmap_offset(pgd, addr); 251 do { 252 pud_t old_pud = *pud; 253 254 next = pud_addr_end(addr, end); 255 256 /* 257 * For 4K granule only, attempt to put down a 1GB block 258 */ 259 if (use_1G_block(addr, next, phys) && !page_mappings_only) { 260 pud_set_huge(pud, phys, prot); 261 262 /* 263 * After the PUD entry has been populated once, we 264 * only allow updates to the permission attributes. 265 */ 266 BUG_ON(!pgattr_change_is_safe(pud_val(old_pud), 267 pud_val(*pud))); 268 } else { 269 alloc_init_pmd(pud, addr, next, phys, prot, 270 pgtable_alloc, page_mappings_only); 271 272 BUG_ON(pud_val(old_pud) != 0 && 273 pud_val(old_pud) != pud_val(*pud)); 274 } 275 phys += next - addr; 276 } while (pud++, addr = next, addr != end); 277 278 pud_clear_fixmap(); 279 } 280 281 static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, 282 unsigned long virt, phys_addr_t size, 283 pgprot_t prot, 284 phys_addr_t (*pgtable_alloc)(void), 285 bool page_mappings_only) 286 { 287 unsigned long addr, length, end, next; 288 pgd_t *pgd = pgd_offset_raw(pgdir, virt); 289 290 /* 291 * If the virtual and physical address don't have the same offset 292 * within a page, we cannot map the region as the caller expects. 293 */ 294 if (WARN_ON((phys ^ virt) & ~PAGE_MASK)) 295 return; 296 297 phys &= PAGE_MASK; 298 addr = virt & PAGE_MASK; 299 length = PAGE_ALIGN(size + (virt & ~PAGE_MASK)); 300 301 end = addr + length; 302 do { 303 next = pgd_addr_end(addr, end); 304 alloc_init_pud(pgd, addr, next, phys, prot, pgtable_alloc, 305 page_mappings_only); 306 phys += next - addr; 307 } while (pgd++, addr = next, addr != end); 308 } 309 310 static phys_addr_t pgd_pgtable_alloc(void) 311 { 312 void *ptr = (void *)__get_free_page(PGALLOC_GFP); 313 if (!ptr || !pgtable_page_ctor(virt_to_page(ptr))) 314 BUG(); 315 316 /* Ensure the zeroed page is visible to the page table walker */ 317 dsb(ishst); 318 return __pa(ptr); 319 } 320 321 /* 322 * This function can only be used to modify existing table entries, 323 * without allocating new levels of table. Note that this permits the 324 * creation of new section or page entries. 325 */ 326 static void __init create_mapping_noalloc(phys_addr_t phys, unsigned long virt, 327 phys_addr_t size, pgprot_t prot) 328 { 329 if (virt < VMALLOC_START) { 330 pr_warn("BUG: not creating mapping for %pa at 0x%016lx - outside kernel range\n", 331 &phys, virt); 332 return; 333 } 334 __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL, false); 335 } 336 337 void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, 338 unsigned long virt, phys_addr_t size, 339 pgprot_t prot, bool page_mappings_only) 340 { 341 BUG_ON(mm == &init_mm); 342 343 __create_pgd_mapping(mm->pgd, phys, virt, size, prot, 344 pgd_pgtable_alloc, page_mappings_only); 345 } 346 347 static void create_mapping_late(phys_addr_t phys, unsigned long virt, 348 phys_addr_t size, pgprot_t prot) 349 { 350 if (virt < VMALLOC_START) { 351 pr_warn("BUG: not creating mapping for %pa at 0x%016lx - outside kernel range\n", 352 &phys, virt); 353 return; 354 } 355 356 __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, 357 NULL, debug_pagealloc_enabled()); 358 } 359 360 static void __init __map_memblock(pgd_t *pgd, phys_addr_t start, phys_addr_t end) 361 { 362 unsigned long kernel_start = __pa(_text); 363 unsigned long kernel_end = __pa(__init_begin); 364 365 /* 366 * Take care not to create a writable alias for the 367 * read-only text and rodata sections of the kernel image. 368 */ 369 370 /* No overlap with the kernel text/rodata */ 371 if (end < kernel_start || start >= kernel_end) { 372 __create_pgd_mapping(pgd, start, __phys_to_virt(start), 373 end - start, PAGE_KERNEL, 374 early_pgtable_alloc, 375 debug_pagealloc_enabled()); 376 return; 377 } 378 379 /* 380 * This block overlaps the kernel text/rodata mappings. 381 * Map the portion(s) which don't overlap. 382 */ 383 if (start < kernel_start) 384 __create_pgd_mapping(pgd, start, 385 __phys_to_virt(start), 386 kernel_start - start, PAGE_KERNEL, 387 early_pgtable_alloc, 388 debug_pagealloc_enabled()); 389 if (kernel_end < end) 390 __create_pgd_mapping(pgd, kernel_end, 391 __phys_to_virt(kernel_end), 392 end - kernel_end, PAGE_KERNEL, 393 early_pgtable_alloc, 394 debug_pagealloc_enabled()); 395 396 /* 397 * Map the linear alias of the [_text, __init_begin) interval as 398 * read-only/non-executable. This makes the contents of the 399 * region accessible to subsystems such as hibernate, but 400 * protects it from inadvertent modification or execution. 401 */ 402 __create_pgd_mapping(pgd, kernel_start, __phys_to_virt(kernel_start), 403 kernel_end - kernel_start, PAGE_KERNEL_RO, 404 early_pgtable_alloc, debug_pagealloc_enabled()); 405 } 406 407 static void __init map_mem(pgd_t *pgd) 408 { 409 struct memblock_region *reg; 410 411 /* map all the memory banks */ 412 for_each_memblock(memory, reg) { 413 phys_addr_t start = reg->base; 414 phys_addr_t end = start + reg->size; 415 416 if (start >= end) 417 break; 418 if (memblock_is_nomap(reg)) 419 continue; 420 421 __map_memblock(pgd, start, end); 422 } 423 } 424 425 void mark_rodata_ro(void) 426 { 427 unsigned long section_size; 428 429 section_size = (unsigned long)_etext - (unsigned long)_text; 430 create_mapping_late(__pa(_text), (unsigned long)_text, 431 section_size, PAGE_KERNEL_ROX); 432 /* 433 * mark .rodata as read only. Use __init_begin rather than __end_rodata 434 * to cover NOTES and EXCEPTION_TABLE. 435 */ 436 section_size = (unsigned long)__init_begin - (unsigned long)__start_rodata; 437 create_mapping_late(__pa(__start_rodata), (unsigned long)__start_rodata, 438 section_size, PAGE_KERNEL_RO); 439 440 /* flush the TLBs after updating live kernel mappings */ 441 flush_tlb_all(); 442 443 debug_checkwx(); 444 } 445 446 static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, 447 pgprot_t prot, struct vm_struct *vma) 448 { 449 phys_addr_t pa_start = __pa(va_start); 450 unsigned long size = va_end - va_start; 451 452 BUG_ON(!PAGE_ALIGNED(pa_start)); 453 BUG_ON(!PAGE_ALIGNED(size)); 454 455 __create_pgd_mapping(pgd, pa_start, (unsigned long)va_start, size, prot, 456 early_pgtable_alloc, debug_pagealloc_enabled()); 457 458 vma->addr = va_start; 459 vma->phys_addr = pa_start; 460 vma->size = size; 461 vma->flags = VM_MAP; 462 vma->caller = __builtin_return_address(0); 463 464 vm_area_add_early(vma); 465 } 466 467 /* 468 * Create fine-grained mappings for the kernel. 469 */ 470 static void __init map_kernel(pgd_t *pgd) 471 { 472 static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_init, vmlinux_data; 473 474 map_kernel_segment(pgd, _text, _etext, PAGE_KERNEL_EXEC, &vmlinux_text); 475 map_kernel_segment(pgd, __start_rodata, __init_begin, PAGE_KERNEL, &vmlinux_rodata); 476 map_kernel_segment(pgd, __init_begin, __init_end, PAGE_KERNEL_EXEC, 477 &vmlinux_init); 478 map_kernel_segment(pgd, _data, _end, PAGE_KERNEL, &vmlinux_data); 479 480 if (!pgd_val(*pgd_offset_raw(pgd, FIXADDR_START))) { 481 /* 482 * The fixmap falls in a separate pgd to the kernel, and doesn't 483 * live in the carveout for the swapper_pg_dir. We can simply 484 * re-use the existing dir for the fixmap. 485 */ 486 set_pgd(pgd_offset_raw(pgd, FIXADDR_START), 487 *pgd_offset_k(FIXADDR_START)); 488 } else if (CONFIG_PGTABLE_LEVELS > 3) { 489 /* 490 * The fixmap shares its top level pgd entry with the kernel 491 * mapping. This can really only occur when we are running 492 * with 16k/4 levels, so we can simply reuse the pud level 493 * entry instead. 494 */ 495 BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES)); 496 set_pud(pud_set_fixmap_offset(pgd, FIXADDR_START), 497 __pud(__pa(bm_pmd) | PUD_TYPE_TABLE)); 498 pud_clear_fixmap(); 499 } else { 500 BUG(); 501 } 502 503 kasan_copy_shadow(pgd); 504 } 505 506 /* 507 * paging_init() sets up the page tables, initialises the zone memory 508 * maps and sets up the zero page. 509 */ 510 void __init paging_init(void) 511 { 512 phys_addr_t pgd_phys = early_pgtable_alloc(); 513 pgd_t *pgd = pgd_set_fixmap(pgd_phys); 514 515 map_kernel(pgd); 516 map_mem(pgd); 517 518 /* 519 * We want to reuse the original swapper_pg_dir so we don't have to 520 * communicate the new address to non-coherent secondaries in 521 * secondary_entry, and so cpu_switch_mm can generate the address with 522 * adrp+add rather than a load from some global variable. 523 * 524 * To do this we need to go via a temporary pgd. 525 */ 526 cpu_replace_ttbr1(__va(pgd_phys)); 527 memcpy(swapper_pg_dir, pgd, PAGE_SIZE); 528 cpu_replace_ttbr1(swapper_pg_dir); 529 530 pgd_clear_fixmap(); 531 memblock_free(pgd_phys, PAGE_SIZE); 532 533 /* 534 * We only reuse the PGD from the swapper_pg_dir, not the pud + pmd 535 * allocated with it. 536 */ 537 memblock_free(__pa(swapper_pg_dir) + PAGE_SIZE, 538 SWAPPER_DIR_SIZE - PAGE_SIZE); 539 } 540 541 /* 542 * Check whether a kernel address is valid (derived from arch/x86/). 543 */ 544 int kern_addr_valid(unsigned long addr) 545 { 546 pgd_t *pgd; 547 pud_t *pud; 548 pmd_t *pmd; 549 pte_t *pte; 550 551 if ((((long)addr) >> VA_BITS) != -1UL) 552 return 0; 553 554 pgd = pgd_offset_k(addr); 555 if (pgd_none(*pgd)) 556 return 0; 557 558 pud = pud_offset(pgd, addr); 559 if (pud_none(*pud)) 560 return 0; 561 562 if (pud_sect(*pud)) 563 return pfn_valid(pud_pfn(*pud)); 564 565 pmd = pmd_offset(pud, addr); 566 if (pmd_none(*pmd)) 567 return 0; 568 569 if (pmd_sect(*pmd)) 570 return pfn_valid(pmd_pfn(*pmd)); 571 572 pte = pte_offset_kernel(pmd, addr); 573 if (pte_none(*pte)) 574 return 0; 575 576 return pfn_valid(pte_pfn(*pte)); 577 } 578 #ifdef CONFIG_SPARSEMEM_VMEMMAP 579 #if !ARM64_SWAPPER_USES_SECTION_MAPS 580 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node) 581 { 582 return vmemmap_populate_basepages(start, end, node); 583 } 584 #else /* !ARM64_SWAPPER_USES_SECTION_MAPS */ 585 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node) 586 { 587 unsigned long addr = start; 588 unsigned long next; 589 pgd_t *pgd; 590 pud_t *pud; 591 pmd_t *pmd; 592 593 do { 594 next = pmd_addr_end(addr, end); 595 596 pgd = vmemmap_pgd_populate(addr, node); 597 if (!pgd) 598 return -ENOMEM; 599 600 pud = vmemmap_pud_populate(pgd, addr, node); 601 if (!pud) 602 return -ENOMEM; 603 604 pmd = pmd_offset(pud, addr); 605 if (pmd_none(*pmd)) { 606 void *p = NULL; 607 608 p = vmemmap_alloc_block_buf(PMD_SIZE, node); 609 if (!p) 610 return -ENOMEM; 611 612 set_pmd(pmd, __pmd(__pa(p) | PROT_SECT_NORMAL)); 613 } else 614 vmemmap_verify((pte_t *)pmd, node, addr, next); 615 } while (addr = next, addr != end); 616 617 return 0; 618 } 619 #endif /* CONFIG_ARM64_64K_PAGES */ 620 void vmemmap_free(unsigned long start, unsigned long end) 621 { 622 } 623 #endif /* CONFIG_SPARSEMEM_VMEMMAP */ 624 625 static inline pud_t * fixmap_pud(unsigned long addr) 626 { 627 pgd_t *pgd = pgd_offset_k(addr); 628 629 BUG_ON(pgd_none(*pgd) || pgd_bad(*pgd)); 630 631 return pud_offset_kimg(pgd, addr); 632 } 633 634 static inline pmd_t * fixmap_pmd(unsigned long addr) 635 { 636 pud_t *pud = fixmap_pud(addr); 637 638 BUG_ON(pud_none(*pud) || pud_bad(*pud)); 639 640 return pmd_offset_kimg(pud, addr); 641 } 642 643 static inline pte_t * fixmap_pte(unsigned long addr) 644 { 645 return &bm_pte[pte_index(addr)]; 646 } 647 648 void __init early_fixmap_init(void) 649 { 650 pgd_t *pgd; 651 pud_t *pud; 652 pmd_t *pmd; 653 unsigned long addr = FIXADDR_START; 654 655 pgd = pgd_offset_k(addr); 656 if (CONFIG_PGTABLE_LEVELS > 3 && 657 !(pgd_none(*pgd) || pgd_page_paddr(*pgd) == __pa(bm_pud))) { 658 /* 659 * We only end up here if the kernel mapping and the fixmap 660 * share the top level pgd entry, which should only happen on 661 * 16k/4 levels configurations. 662 */ 663 BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES)); 664 pud = pud_offset_kimg(pgd, addr); 665 } else { 666 pgd_populate(&init_mm, pgd, bm_pud); 667 pud = fixmap_pud(addr); 668 } 669 pud_populate(&init_mm, pud, bm_pmd); 670 pmd = fixmap_pmd(addr); 671 pmd_populate_kernel(&init_mm, pmd, bm_pte); 672 673 /* 674 * The boot-ioremap range spans multiple pmds, for which 675 * we are not prepared: 676 */ 677 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 678 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 679 680 if ((pmd != fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN))) 681 || pmd != fixmap_pmd(fix_to_virt(FIX_BTMAP_END))) { 682 WARN_ON(1); 683 pr_warn("pmd %p != %p, %p\n", 684 pmd, fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)), 685 fixmap_pmd(fix_to_virt(FIX_BTMAP_END))); 686 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 687 fix_to_virt(FIX_BTMAP_BEGIN)); 688 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", 689 fix_to_virt(FIX_BTMAP_END)); 690 691 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 692 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); 693 } 694 } 695 696 void __set_fixmap(enum fixed_addresses idx, 697 phys_addr_t phys, pgprot_t flags) 698 { 699 unsigned long addr = __fix_to_virt(idx); 700 pte_t *pte; 701 702 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses); 703 704 pte = fixmap_pte(addr); 705 706 if (pgprot_val(flags)) { 707 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags)); 708 } else { 709 pte_clear(&init_mm, addr, pte); 710 flush_tlb_kernel_range(addr, addr+PAGE_SIZE); 711 } 712 } 713 714 void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot) 715 { 716 const u64 dt_virt_base = __fix_to_virt(FIX_FDT); 717 int offset; 718 void *dt_virt; 719 720 /* 721 * Check whether the physical FDT address is set and meets the minimum 722 * alignment requirement. Since we are relying on MIN_FDT_ALIGN to be 723 * at least 8 bytes so that we can always access the magic and size 724 * fields of the FDT header after mapping the first chunk, double check 725 * here if that is indeed the case. 726 */ 727 BUILD_BUG_ON(MIN_FDT_ALIGN < 8); 728 if (!dt_phys || dt_phys % MIN_FDT_ALIGN) 729 return NULL; 730 731 /* 732 * Make sure that the FDT region can be mapped without the need to 733 * allocate additional translation table pages, so that it is safe 734 * to call create_mapping_noalloc() this early. 735 * 736 * On 64k pages, the FDT will be mapped using PTEs, so we need to 737 * be in the same PMD as the rest of the fixmap. 738 * On 4k pages, we'll use section mappings for the FDT so we only 739 * have to be in the same PUD. 740 */ 741 BUILD_BUG_ON(dt_virt_base % SZ_2M); 742 743 BUILD_BUG_ON(__fix_to_virt(FIX_FDT_END) >> SWAPPER_TABLE_SHIFT != 744 __fix_to_virt(FIX_BTMAP_BEGIN) >> SWAPPER_TABLE_SHIFT); 745 746 offset = dt_phys % SWAPPER_BLOCK_SIZE; 747 dt_virt = (void *)dt_virt_base + offset; 748 749 /* map the first chunk so we can read the size from the header */ 750 create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), 751 dt_virt_base, SWAPPER_BLOCK_SIZE, prot); 752 753 if (fdt_magic(dt_virt) != FDT_MAGIC) 754 return NULL; 755 756 *size = fdt_totalsize(dt_virt); 757 if (*size > MAX_FDT_SIZE) 758 return NULL; 759 760 if (offset + *size > SWAPPER_BLOCK_SIZE) 761 create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base, 762 round_up(offset + *size, SWAPPER_BLOCK_SIZE), prot); 763 764 return dt_virt; 765 } 766 767 void *__init fixmap_remap_fdt(phys_addr_t dt_phys) 768 { 769 void *dt_virt; 770 int size; 771 772 dt_virt = __fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO); 773 if (!dt_virt) 774 return NULL; 775 776 memblock_reserve(dt_phys, size); 777 return dt_virt; 778 } 779 780 int __init arch_ioremap_pud_supported(void) 781 { 782 /* only 4k granule supports level 1 block mappings */ 783 return IS_ENABLED(CONFIG_ARM64_4K_PAGES); 784 } 785 786 int __init arch_ioremap_pmd_supported(void) 787 { 788 return 1; 789 } 790 791 int pud_set_huge(pud_t *pud, phys_addr_t phys, pgprot_t prot) 792 { 793 BUG_ON(phys & ~PUD_MASK); 794 set_pud(pud, __pud(phys | PUD_TYPE_SECT | pgprot_val(mk_sect_prot(prot)))); 795 return 1; 796 } 797 798 int pmd_set_huge(pmd_t *pmd, phys_addr_t phys, pgprot_t prot) 799 { 800 BUG_ON(phys & ~PMD_MASK); 801 set_pmd(pmd, __pmd(phys | PMD_TYPE_SECT | pgprot_val(mk_sect_prot(prot)))); 802 return 1; 803 } 804 805 int pud_clear_huge(pud_t *pud) 806 { 807 if (!pud_sect(*pud)) 808 return 0; 809 pud_clear(pud); 810 return 1; 811 } 812 813 int pmd_clear_huge(pmd_t *pmd) 814 { 815 if (!pmd_sect(*pmd)) 816 return 0; 817 pmd_clear(pmd); 818 return 1; 819 } 820