1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2012 ARM Ltd. 4 */ 5 #ifndef __ASM_PGTABLE_H 6 #define __ASM_PGTABLE_H 7 8 #include <asm/bug.h> 9 #include <asm/proc-fns.h> 10 11 #include <asm/memory.h> 12 #include <asm/mte.h> 13 #include <asm/pgtable-hwdef.h> 14 #include <asm/pgtable-prot.h> 15 #include <asm/tlbflush.h> 16 17 /* 18 * VMALLOC range. 19 * 20 * VMALLOC_START: beginning of the kernel vmalloc space 21 * VMALLOC_END: extends to the available space below vmemmap, PCI I/O space 22 * and fixed mappings 23 */ 24 #define VMALLOC_START (MODULES_END) 25 #define VMALLOC_END (VMEMMAP_START - SZ_256M) 26 27 #define vmemmap ((struct page *)VMEMMAP_START - (memstart_addr >> PAGE_SHIFT)) 28 29 #ifndef __ASSEMBLY__ 30 31 #include <asm/cmpxchg.h> 32 #include <asm/fixmap.h> 33 #include <linux/mmdebug.h> 34 #include <linux/mm_types.h> 35 #include <linux/sched.h> 36 #include <linux/page_table_check.h> 37 38 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 39 #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE 40 41 /* Set stride and tlb_level in flush_*_tlb_range */ 42 #define flush_pmd_tlb_range(vma, addr, end) \ 43 __flush_tlb_range(vma, addr, end, PMD_SIZE, false, 2) 44 #define flush_pud_tlb_range(vma, addr, end) \ 45 __flush_tlb_range(vma, addr, end, PUD_SIZE, false, 1) 46 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 47 48 static inline bool arch_thp_swp_supported(void) 49 { 50 return !system_supports_mte(); 51 } 52 #define arch_thp_swp_supported arch_thp_swp_supported 53 54 /* 55 * Outside of a few very special situations (e.g. hibernation), we always 56 * use broadcast TLB invalidation instructions, therefore a spurious page 57 * fault on one CPU which has been handled concurrently by another CPU 58 * does not need to perform additional invalidation. 59 */ 60 #define flush_tlb_fix_spurious_fault(vma, address) do { } while (0) 61 62 /* 63 * ZERO_PAGE is a global shared page that is always zero: used 64 * for zero-mapped memory areas etc.. 65 */ 66 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; 67 #define ZERO_PAGE(vaddr) phys_to_page(__pa_symbol(empty_zero_page)) 68 69 #define pte_ERROR(e) \ 70 pr_err("%s:%d: bad pte %016llx.\n", __FILE__, __LINE__, pte_val(e)) 71 72 /* 73 * Macros to convert between a physical address and its placement in a 74 * page table entry, taking care of 52-bit addresses. 75 */ 76 #ifdef CONFIG_ARM64_PA_BITS_52 77 static inline phys_addr_t __pte_to_phys(pte_t pte) 78 { 79 return (pte_val(pte) & PTE_ADDR_LOW) | 80 ((pte_val(pte) & PTE_ADDR_HIGH) << 36); 81 } 82 static inline pteval_t __phys_to_pte_val(phys_addr_t phys) 83 { 84 return (phys | (phys >> 36)) & PTE_ADDR_MASK; 85 } 86 #else 87 #define __pte_to_phys(pte) (pte_val(pte) & PTE_ADDR_MASK) 88 #define __phys_to_pte_val(phys) (phys) 89 #endif 90 91 #define pte_pfn(pte) (__pte_to_phys(pte) >> PAGE_SHIFT) 92 #define pfn_pte(pfn,prot) \ 93 __pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 94 95 #define pte_none(pte) (!pte_val(pte)) 96 #define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0)) 97 #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) 98 99 /* 100 * The following only work if pte_present(). Undefined behaviour otherwise. 101 */ 102 #define pte_present(pte) (!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE))) 103 #define pte_young(pte) (!!(pte_val(pte) & PTE_AF)) 104 #define pte_special(pte) (!!(pte_val(pte) & PTE_SPECIAL)) 105 #define pte_write(pte) (!!(pte_val(pte) & PTE_WRITE)) 106 #define pte_user(pte) (!!(pte_val(pte) & PTE_USER)) 107 #define pte_user_exec(pte) (!(pte_val(pte) & PTE_UXN)) 108 #define pte_cont(pte) (!!(pte_val(pte) & PTE_CONT)) 109 #define pte_devmap(pte) (!!(pte_val(pte) & PTE_DEVMAP)) 110 #define pte_tagged(pte) ((pte_val(pte) & PTE_ATTRINDX_MASK) == \ 111 PTE_ATTRINDX(MT_NORMAL_TAGGED)) 112 113 #define pte_cont_addr_end(addr, end) \ 114 ({ unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK; \ 115 (__boundary - 1 < (end) - 1) ? __boundary : (end); \ 116 }) 117 118 #define pmd_cont_addr_end(addr, end) \ 119 ({ unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK; \ 120 (__boundary - 1 < (end) - 1) ? __boundary : (end); \ 121 }) 122 123 #define pte_hw_dirty(pte) (pte_write(pte) && !(pte_val(pte) & PTE_RDONLY)) 124 #define pte_sw_dirty(pte) (!!(pte_val(pte) & PTE_DIRTY)) 125 #define pte_dirty(pte) (pte_sw_dirty(pte) || pte_hw_dirty(pte)) 126 127 #define pte_valid(pte) (!!(pte_val(pte) & PTE_VALID)) 128 /* 129 * Execute-only user mappings do not have the PTE_USER bit set. All valid 130 * kernel mappings have the PTE_UXN bit set. 131 */ 132 #define pte_valid_not_user(pte) \ 133 ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN)) 134 /* 135 * Could the pte be present in the TLB? We must check mm_tlb_flush_pending 136 * so that we don't erroneously return false for pages that have been 137 * remapped as PROT_NONE but are yet to be flushed from the TLB. 138 * Note that we can't make any assumptions based on the state of the access 139 * flag, since ptep_clear_flush_young() elides a DSB when invalidating the 140 * TLB. 141 */ 142 #define pte_accessible(mm, pte) \ 143 (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte)) 144 145 /* 146 * p??_access_permitted() is true for valid user mappings (PTE_USER 147 * bit set, subject to the write permission check). For execute-only 148 * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits 149 * not set) must return false. PROT_NONE mappings do not have the 150 * PTE_VALID bit set. 151 */ 152 #define pte_access_permitted(pte, write) \ 153 (((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte))) 154 #define pmd_access_permitted(pmd, write) \ 155 (pte_access_permitted(pmd_pte(pmd), (write))) 156 #define pud_access_permitted(pud, write) \ 157 (pte_access_permitted(pud_pte(pud), (write))) 158 159 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot) 160 { 161 pte_val(pte) &= ~pgprot_val(prot); 162 return pte; 163 } 164 165 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot) 166 { 167 pte_val(pte) |= pgprot_val(prot); 168 return pte; 169 } 170 171 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot) 172 { 173 pmd_val(pmd) &= ~pgprot_val(prot); 174 return pmd; 175 } 176 177 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot) 178 { 179 pmd_val(pmd) |= pgprot_val(prot); 180 return pmd; 181 } 182 183 static inline pte_t pte_mkwrite(pte_t pte) 184 { 185 pte = set_pte_bit(pte, __pgprot(PTE_WRITE)); 186 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY)); 187 return pte; 188 } 189 190 static inline pte_t pte_mkclean(pte_t pte) 191 { 192 pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY)); 193 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY)); 194 195 return pte; 196 } 197 198 static inline pte_t pte_mkdirty(pte_t pte) 199 { 200 pte = set_pte_bit(pte, __pgprot(PTE_DIRTY)); 201 202 if (pte_write(pte)) 203 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY)); 204 205 return pte; 206 } 207 208 static inline pte_t pte_wrprotect(pte_t pte) 209 { 210 /* 211 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY 212 * clear), set the PTE_DIRTY bit. 213 */ 214 if (pte_hw_dirty(pte)) 215 pte = pte_mkdirty(pte); 216 217 pte = clear_pte_bit(pte, __pgprot(PTE_WRITE)); 218 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY)); 219 return pte; 220 } 221 222 static inline pte_t pte_mkold(pte_t pte) 223 { 224 return clear_pte_bit(pte, __pgprot(PTE_AF)); 225 } 226 227 static inline pte_t pte_mkyoung(pte_t pte) 228 { 229 return set_pte_bit(pte, __pgprot(PTE_AF)); 230 } 231 232 static inline pte_t pte_mkspecial(pte_t pte) 233 { 234 return set_pte_bit(pte, __pgprot(PTE_SPECIAL)); 235 } 236 237 static inline pte_t pte_mkcont(pte_t pte) 238 { 239 pte = set_pte_bit(pte, __pgprot(PTE_CONT)); 240 return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE)); 241 } 242 243 static inline pte_t pte_mknoncont(pte_t pte) 244 { 245 return clear_pte_bit(pte, __pgprot(PTE_CONT)); 246 } 247 248 static inline pte_t pte_mkpresent(pte_t pte) 249 { 250 return set_pte_bit(pte, __pgprot(PTE_VALID)); 251 } 252 253 static inline pmd_t pmd_mkcont(pmd_t pmd) 254 { 255 return __pmd(pmd_val(pmd) | PMD_SECT_CONT); 256 } 257 258 static inline pte_t pte_mkdevmap(pte_t pte) 259 { 260 return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL)); 261 } 262 263 static inline void set_pte(pte_t *ptep, pte_t pte) 264 { 265 WRITE_ONCE(*ptep, pte); 266 267 /* 268 * Only if the new pte is valid and kernel, otherwise TLB maintenance 269 * or update_mmu_cache() have the necessary barriers. 270 */ 271 if (pte_valid_not_user(pte)) { 272 dsb(ishst); 273 isb(); 274 } 275 } 276 277 extern void __sync_icache_dcache(pte_t pteval); 278 279 /* 280 * PTE bits configuration in the presence of hardware Dirty Bit Management 281 * (PTE_WRITE == PTE_DBM): 282 * 283 * Dirty Writable | PTE_RDONLY PTE_WRITE PTE_DIRTY (sw) 284 * 0 0 | 1 0 0 285 * 0 1 | 1 1 0 286 * 1 0 | 1 0 1 287 * 1 1 | 0 1 x 288 * 289 * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via 290 * the page fault mechanism. Checking the dirty status of a pte becomes: 291 * 292 * PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY) 293 */ 294 295 static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep, 296 pte_t pte) 297 { 298 pte_t old_pte; 299 300 if (!IS_ENABLED(CONFIG_DEBUG_VM)) 301 return; 302 303 old_pte = READ_ONCE(*ptep); 304 305 if (!pte_valid(old_pte) || !pte_valid(pte)) 306 return; 307 if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1) 308 return; 309 310 /* 311 * Check for potential race with hardware updates of the pte 312 * (ptep_set_access_flags safely changes valid ptes without going 313 * through an invalid entry). 314 */ 315 VM_WARN_ONCE(!pte_young(pte), 316 "%s: racy access flag clearing: 0x%016llx -> 0x%016llx", 317 __func__, pte_val(old_pte), pte_val(pte)); 318 VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte), 319 "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx", 320 __func__, pte_val(old_pte), pte_val(pte)); 321 } 322 323 static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, 324 pte_t *ptep, pte_t pte) 325 { 326 if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte)) 327 __sync_icache_dcache(pte); 328 329 /* 330 * If the PTE would provide user space access to the tags associated 331 * with it then ensure that the MTE tags are synchronised. Although 332 * pte_access_permitted() returns false for exec only mappings, they 333 * don't expose tags (instruction fetches don't check tags). 334 */ 335 if (system_supports_mte() && pte_access_permitted(pte, false) && 336 !pte_special(pte)) { 337 pte_t old_pte = READ_ONCE(*ptep); 338 /* 339 * We only need to synchronise if the new PTE has tags enabled 340 * or if swapping in (in which case another mapping may have 341 * set tags in the past even if this PTE isn't tagged). 342 * (!pte_none() && !pte_present()) is an open coded version of 343 * is_swap_pte() 344 */ 345 if (pte_tagged(pte) || (!pte_none(old_pte) && !pte_present(old_pte))) 346 mte_sync_tags(old_pte, pte); 347 } 348 349 __check_racy_pte_update(mm, ptep, pte); 350 351 set_pte(ptep, pte); 352 } 353 354 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 355 pte_t *ptep, pte_t pte) 356 { 357 page_table_check_pte_set(mm, addr, ptep, pte); 358 return __set_pte_at(mm, addr, ptep, pte); 359 } 360 361 /* 362 * Huge pte definitions. 363 */ 364 #define pte_mkhuge(pte) (__pte(pte_val(pte) & ~PTE_TABLE_BIT)) 365 366 /* 367 * Hugetlb definitions. 368 */ 369 #define HUGE_MAX_HSTATE 4 370 #define HPAGE_SHIFT PMD_SHIFT 371 #define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT) 372 #define HPAGE_MASK (~(HPAGE_SIZE - 1)) 373 #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT) 374 375 static inline pte_t pgd_pte(pgd_t pgd) 376 { 377 return __pte(pgd_val(pgd)); 378 } 379 380 static inline pte_t p4d_pte(p4d_t p4d) 381 { 382 return __pte(p4d_val(p4d)); 383 } 384 385 static inline pte_t pud_pte(pud_t pud) 386 { 387 return __pte(pud_val(pud)); 388 } 389 390 static inline pud_t pte_pud(pte_t pte) 391 { 392 return __pud(pte_val(pte)); 393 } 394 395 static inline pmd_t pud_pmd(pud_t pud) 396 { 397 return __pmd(pud_val(pud)); 398 } 399 400 static inline pte_t pmd_pte(pmd_t pmd) 401 { 402 return __pte(pmd_val(pmd)); 403 } 404 405 static inline pmd_t pte_pmd(pte_t pte) 406 { 407 return __pmd(pte_val(pte)); 408 } 409 410 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot) 411 { 412 return __pgprot((pgprot_val(prot) & ~PUD_TABLE_BIT) | PUD_TYPE_SECT); 413 } 414 415 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot) 416 { 417 return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT); 418 } 419 420 #define __HAVE_ARCH_PTE_SWP_EXCLUSIVE 421 static inline pte_t pte_swp_mkexclusive(pte_t pte) 422 { 423 return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE)); 424 } 425 426 static inline int pte_swp_exclusive(pte_t pte) 427 { 428 return pte_val(pte) & PTE_SWP_EXCLUSIVE; 429 } 430 431 static inline pte_t pte_swp_clear_exclusive(pte_t pte) 432 { 433 return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE)); 434 } 435 436 /* 437 * Select all bits except the pfn 438 */ 439 static inline pgprot_t pte_pgprot(pte_t pte) 440 { 441 unsigned long pfn = pte_pfn(pte); 442 443 return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte)); 444 } 445 446 #ifdef CONFIG_NUMA_BALANCING 447 /* 448 * See the comment in include/linux/pgtable.h 449 */ 450 static inline int pte_protnone(pte_t pte) 451 { 452 return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE; 453 } 454 455 static inline int pmd_protnone(pmd_t pmd) 456 { 457 return pte_protnone(pmd_pte(pmd)); 458 } 459 #endif 460 461 #define pmd_present_invalid(pmd) (!!(pmd_val(pmd) & PMD_PRESENT_INVALID)) 462 463 static inline int pmd_present(pmd_t pmd) 464 { 465 return pte_present(pmd_pte(pmd)) || pmd_present_invalid(pmd); 466 } 467 468 /* 469 * THP definitions. 470 */ 471 472 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 473 static inline int pmd_trans_huge(pmd_t pmd) 474 { 475 return pmd_val(pmd) && pmd_present(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT); 476 } 477 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 478 479 #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd)) 480 #define pmd_young(pmd) pte_young(pmd_pte(pmd)) 481 #define pmd_valid(pmd) pte_valid(pmd_pte(pmd)) 482 #define pmd_user(pmd) pte_user(pmd_pte(pmd)) 483 #define pmd_user_exec(pmd) pte_user_exec(pmd_pte(pmd)) 484 #define pmd_cont(pmd) pte_cont(pmd_pte(pmd)) 485 #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd))) 486 #define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd))) 487 #define pmd_mkwrite(pmd) pte_pmd(pte_mkwrite(pmd_pte(pmd))) 488 #define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd))) 489 #define pmd_mkdirty(pmd) pte_pmd(pte_mkdirty(pmd_pte(pmd))) 490 #define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd))) 491 492 static inline pmd_t pmd_mkinvalid(pmd_t pmd) 493 { 494 pmd = set_pmd_bit(pmd, __pgprot(PMD_PRESENT_INVALID)); 495 pmd = clear_pmd_bit(pmd, __pgprot(PMD_SECT_VALID)); 496 497 return pmd; 498 } 499 500 #define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd)) 501 502 #define pmd_write(pmd) pte_write(pmd_pte(pmd)) 503 504 #define pmd_mkhuge(pmd) (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT)) 505 506 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 507 #define pmd_devmap(pmd) pte_devmap(pmd_pte(pmd)) 508 #endif 509 static inline pmd_t pmd_mkdevmap(pmd_t pmd) 510 { 511 return pte_pmd(set_pte_bit(pmd_pte(pmd), __pgprot(PTE_DEVMAP))); 512 } 513 514 #define __pmd_to_phys(pmd) __pte_to_phys(pmd_pte(pmd)) 515 #define __phys_to_pmd_val(phys) __phys_to_pte_val(phys) 516 #define pmd_pfn(pmd) ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT) 517 #define pfn_pmd(pfn,prot) __pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 518 #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot) 519 520 #define pud_young(pud) pte_young(pud_pte(pud)) 521 #define pud_mkyoung(pud) pte_pud(pte_mkyoung(pud_pte(pud))) 522 #define pud_write(pud) pte_write(pud_pte(pud)) 523 524 #define pud_mkhuge(pud) (__pud(pud_val(pud) & ~PUD_TABLE_BIT)) 525 526 #define __pud_to_phys(pud) __pte_to_phys(pud_pte(pud)) 527 #define __phys_to_pud_val(phys) __phys_to_pte_val(phys) 528 #define pud_pfn(pud) ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT) 529 #define pfn_pud(pfn,prot) __pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 530 531 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, 532 pmd_t *pmdp, pmd_t pmd) 533 { 534 page_table_check_pmd_set(mm, addr, pmdp, pmd); 535 return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd)); 536 } 537 538 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr, 539 pud_t *pudp, pud_t pud) 540 { 541 page_table_check_pud_set(mm, addr, pudp, pud); 542 return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud)); 543 } 544 545 #define __p4d_to_phys(p4d) __pte_to_phys(p4d_pte(p4d)) 546 #define __phys_to_p4d_val(phys) __phys_to_pte_val(phys) 547 548 #define __pgd_to_phys(pgd) __pte_to_phys(pgd_pte(pgd)) 549 #define __phys_to_pgd_val(phys) __phys_to_pte_val(phys) 550 551 #define __pgprot_modify(prot,mask,bits) \ 552 __pgprot((pgprot_val(prot) & ~(mask)) | (bits)) 553 554 #define pgprot_nx(prot) \ 555 __pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN) 556 557 /* 558 * Mark the prot value as uncacheable and unbufferable. 559 */ 560 #define pgprot_noncached(prot) \ 561 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN) 562 #define pgprot_writecombine(prot) \ 563 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN) 564 #define pgprot_device(prot) \ 565 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN) 566 #define pgprot_tagged(prot) \ 567 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED)) 568 #define pgprot_mhp pgprot_tagged 569 /* 570 * DMA allocations for non-coherent devices use what the Arm architecture calls 571 * "Normal non-cacheable" memory, which permits speculation, unaligned accesses 572 * and merging of writes. This is different from "Device-nGnR[nE]" memory which 573 * is intended for MMIO and thus forbids speculation, preserves access size, 574 * requires strict alignment and can also force write responses to come from the 575 * endpoint. 576 */ 577 #define pgprot_dmacoherent(prot) \ 578 __pgprot_modify(prot, PTE_ATTRINDX_MASK, \ 579 PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN) 580 581 #define __HAVE_PHYS_MEM_ACCESS_PROT 582 struct file; 583 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 584 unsigned long size, pgprot_t vma_prot); 585 586 #define pmd_none(pmd) (!pmd_val(pmd)) 587 588 #define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ 589 PMD_TYPE_TABLE) 590 #define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ 591 PMD_TYPE_SECT) 592 #define pmd_leaf(pmd) (pmd_present(pmd) && !pmd_table(pmd)) 593 #define pmd_bad(pmd) (!pmd_table(pmd)) 594 595 #define pmd_leaf_size(pmd) (pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE) 596 #define pte_leaf_size(pte) (pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE) 597 598 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3 599 static inline bool pud_sect(pud_t pud) { return false; } 600 static inline bool pud_table(pud_t pud) { return true; } 601 #else 602 #define pud_sect(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \ 603 PUD_TYPE_SECT) 604 #define pud_table(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \ 605 PUD_TYPE_TABLE) 606 #endif 607 608 extern pgd_t init_pg_dir[PTRS_PER_PGD]; 609 extern pgd_t init_pg_end[]; 610 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 611 extern pgd_t idmap_pg_dir[PTRS_PER_PGD]; 612 extern pgd_t idmap_pg_end[]; 613 extern pgd_t tramp_pg_dir[PTRS_PER_PGD]; 614 extern pgd_t reserved_pg_dir[PTRS_PER_PGD]; 615 616 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd); 617 618 static inline bool in_swapper_pgdir(void *addr) 619 { 620 return ((unsigned long)addr & PAGE_MASK) == 621 ((unsigned long)swapper_pg_dir & PAGE_MASK); 622 } 623 624 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd) 625 { 626 #ifdef __PAGETABLE_PMD_FOLDED 627 if (in_swapper_pgdir(pmdp)) { 628 set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd))); 629 return; 630 } 631 #endif /* __PAGETABLE_PMD_FOLDED */ 632 633 WRITE_ONCE(*pmdp, pmd); 634 635 if (pmd_valid(pmd)) { 636 dsb(ishst); 637 isb(); 638 } 639 } 640 641 static inline void pmd_clear(pmd_t *pmdp) 642 { 643 set_pmd(pmdp, __pmd(0)); 644 } 645 646 static inline phys_addr_t pmd_page_paddr(pmd_t pmd) 647 { 648 return __pmd_to_phys(pmd); 649 } 650 651 static inline unsigned long pmd_page_vaddr(pmd_t pmd) 652 { 653 return (unsigned long)__va(pmd_page_paddr(pmd)); 654 } 655 656 /* Find an entry in the third-level page table. */ 657 #define pte_offset_phys(dir,addr) (pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t)) 658 659 #define pte_set_fixmap(addr) ((pte_t *)set_fixmap_offset(FIX_PTE, addr)) 660 #define pte_set_fixmap_offset(pmd, addr) pte_set_fixmap(pte_offset_phys(pmd, addr)) 661 #define pte_clear_fixmap() clear_fixmap(FIX_PTE) 662 663 #define pmd_page(pmd) phys_to_page(__pmd_to_phys(pmd)) 664 665 /* use ONLY for statically allocated translation tables */ 666 #define pte_offset_kimg(dir,addr) ((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr)))) 667 668 /* 669 * Conversion functions: convert a page and protection to a page entry, 670 * and a page entry and page directory to the page they refer to. 671 */ 672 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page),prot) 673 674 #if CONFIG_PGTABLE_LEVELS > 2 675 676 #define pmd_ERROR(e) \ 677 pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e)) 678 679 #define pud_none(pud) (!pud_val(pud)) 680 #define pud_bad(pud) (!pud_table(pud)) 681 #define pud_present(pud) pte_present(pud_pte(pud)) 682 #define pud_leaf(pud) (pud_present(pud) && !pud_table(pud)) 683 #define pud_valid(pud) pte_valid(pud_pte(pud)) 684 #define pud_user(pud) pte_user(pud_pte(pud)) 685 686 687 static inline void set_pud(pud_t *pudp, pud_t pud) 688 { 689 #ifdef __PAGETABLE_PUD_FOLDED 690 if (in_swapper_pgdir(pudp)) { 691 set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud))); 692 return; 693 } 694 #endif /* __PAGETABLE_PUD_FOLDED */ 695 696 WRITE_ONCE(*pudp, pud); 697 698 if (pud_valid(pud)) { 699 dsb(ishst); 700 isb(); 701 } 702 } 703 704 static inline void pud_clear(pud_t *pudp) 705 { 706 set_pud(pudp, __pud(0)); 707 } 708 709 static inline phys_addr_t pud_page_paddr(pud_t pud) 710 { 711 return __pud_to_phys(pud); 712 } 713 714 static inline pmd_t *pud_pgtable(pud_t pud) 715 { 716 return (pmd_t *)__va(pud_page_paddr(pud)); 717 } 718 719 /* Find an entry in the second-level page table. */ 720 #define pmd_offset_phys(dir, addr) (pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t)) 721 722 #define pmd_set_fixmap(addr) ((pmd_t *)set_fixmap_offset(FIX_PMD, addr)) 723 #define pmd_set_fixmap_offset(pud, addr) pmd_set_fixmap(pmd_offset_phys(pud, addr)) 724 #define pmd_clear_fixmap() clear_fixmap(FIX_PMD) 725 726 #define pud_page(pud) phys_to_page(__pud_to_phys(pud)) 727 728 /* use ONLY for statically allocated translation tables */ 729 #define pmd_offset_kimg(dir,addr) ((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr)))) 730 731 #else 732 733 #define pud_page_paddr(pud) ({ BUILD_BUG(); 0; }) 734 735 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */ 736 #define pmd_set_fixmap(addr) NULL 737 #define pmd_set_fixmap_offset(pudp, addr) ((pmd_t *)pudp) 738 #define pmd_clear_fixmap() 739 740 #define pmd_offset_kimg(dir,addr) ((pmd_t *)dir) 741 742 #endif /* CONFIG_PGTABLE_LEVELS > 2 */ 743 744 #if CONFIG_PGTABLE_LEVELS > 3 745 746 #define pud_ERROR(e) \ 747 pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e)) 748 749 #define p4d_none(p4d) (!p4d_val(p4d)) 750 #define p4d_bad(p4d) (!(p4d_val(p4d) & 2)) 751 #define p4d_present(p4d) (p4d_val(p4d)) 752 753 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d) 754 { 755 if (in_swapper_pgdir(p4dp)) { 756 set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d))); 757 return; 758 } 759 760 WRITE_ONCE(*p4dp, p4d); 761 dsb(ishst); 762 isb(); 763 } 764 765 static inline void p4d_clear(p4d_t *p4dp) 766 { 767 set_p4d(p4dp, __p4d(0)); 768 } 769 770 static inline phys_addr_t p4d_page_paddr(p4d_t p4d) 771 { 772 return __p4d_to_phys(p4d); 773 } 774 775 static inline pud_t *p4d_pgtable(p4d_t p4d) 776 { 777 return (pud_t *)__va(p4d_page_paddr(p4d)); 778 } 779 780 /* Find an entry in the first-level page table. */ 781 #define pud_offset_phys(dir, addr) (p4d_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t)) 782 783 #define pud_set_fixmap(addr) ((pud_t *)set_fixmap_offset(FIX_PUD, addr)) 784 #define pud_set_fixmap_offset(p4d, addr) pud_set_fixmap(pud_offset_phys(p4d, addr)) 785 #define pud_clear_fixmap() clear_fixmap(FIX_PUD) 786 787 #define p4d_page(p4d) pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d))) 788 789 /* use ONLY for statically allocated translation tables */ 790 #define pud_offset_kimg(dir,addr) ((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr)))) 791 792 #else 793 794 #define p4d_page_paddr(p4d) ({ BUILD_BUG(); 0;}) 795 #define pgd_page_paddr(pgd) ({ BUILD_BUG(); 0;}) 796 797 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */ 798 #define pud_set_fixmap(addr) NULL 799 #define pud_set_fixmap_offset(pgdp, addr) ((pud_t *)pgdp) 800 #define pud_clear_fixmap() 801 802 #define pud_offset_kimg(dir,addr) ((pud_t *)dir) 803 804 #endif /* CONFIG_PGTABLE_LEVELS > 3 */ 805 806 #define pgd_ERROR(e) \ 807 pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e)) 808 809 #define pgd_set_fixmap(addr) ((pgd_t *)set_fixmap_offset(FIX_PGD, addr)) 810 #define pgd_clear_fixmap() clear_fixmap(FIX_PGD) 811 812 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 813 { 814 /* 815 * Normal and Normal-Tagged are two different memory types and indices 816 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK. 817 */ 818 const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY | 819 PTE_PROT_NONE | PTE_VALID | PTE_WRITE | PTE_GP | 820 PTE_ATTRINDX_MASK; 821 /* preserve the hardware dirty information */ 822 if (pte_hw_dirty(pte)) 823 pte = pte_mkdirty(pte); 824 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 825 return pte; 826 } 827 828 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) 829 { 830 return pte_pmd(pte_modify(pmd_pte(pmd), newprot)); 831 } 832 833 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS 834 extern int ptep_set_access_flags(struct vm_area_struct *vma, 835 unsigned long address, pte_t *ptep, 836 pte_t entry, int dirty); 837 838 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 839 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS 840 static inline int pmdp_set_access_flags(struct vm_area_struct *vma, 841 unsigned long address, pmd_t *pmdp, 842 pmd_t entry, int dirty) 843 { 844 return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty); 845 } 846 847 static inline int pud_devmap(pud_t pud) 848 { 849 return 0; 850 } 851 852 static inline int pgd_devmap(pgd_t pgd) 853 { 854 return 0; 855 } 856 #endif 857 858 #ifdef CONFIG_PAGE_TABLE_CHECK 859 static inline bool pte_user_accessible_page(pte_t pte) 860 { 861 return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte)); 862 } 863 864 static inline bool pmd_user_accessible_page(pmd_t pmd) 865 { 866 return pmd_present(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd)); 867 } 868 869 static inline bool pud_user_accessible_page(pud_t pud) 870 { 871 return pud_present(pud) && pud_user(pud); 872 } 873 #endif 874 875 /* 876 * Atomic pte/pmd modifications. 877 */ 878 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG 879 static inline int __ptep_test_and_clear_young(pte_t *ptep) 880 { 881 pte_t old_pte, pte; 882 883 pte = READ_ONCE(*ptep); 884 do { 885 old_pte = pte; 886 pte = pte_mkold(pte); 887 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep), 888 pte_val(old_pte), pte_val(pte)); 889 } while (pte_val(pte) != pte_val(old_pte)); 890 891 return pte_young(pte); 892 } 893 894 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, 895 unsigned long address, 896 pte_t *ptep) 897 { 898 return __ptep_test_and_clear_young(ptep); 899 } 900 901 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH 902 static inline int ptep_clear_flush_young(struct vm_area_struct *vma, 903 unsigned long address, pte_t *ptep) 904 { 905 int young = ptep_test_and_clear_young(vma, address, ptep); 906 907 if (young) { 908 /* 909 * We can elide the trailing DSB here since the worst that can 910 * happen is that a CPU continues to use the young entry in its 911 * TLB and we mistakenly reclaim the associated page. The 912 * window for such an event is bounded by the next 913 * context-switch, which provides a DSB to complete the TLB 914 * invalidation. 915 */ 916 flush_tlb_page_nosync(vma, address); 917 } 918 919 return young; 920 } 921 922 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 923 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG 924 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, 925 unsigned long address, 926 pmd_t *pmdp) 927 { 928 return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp); 929 } 930 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 931 932 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR 933 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, 934 unsigned long address, pte_t *ptep) 935 { 936 pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0)); 937 938 page_table_check_pte_clear(mm, address, pte); 939 940 return pte; 941 } 942 943 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 944 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR 945 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, 946 unsigned long address, pmd_t *pmdp) 947 { 948 pmd_t pmd = __pmd(xchg_relaxed(&pmd_val(*pmdp), 0)); 949 950 page_table_check_pmd_clear(mm, address, pmd); 951 952 return pmd; 953 } 954 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 955 956 /* 957 * ptep_set_wrprotect - mark read-only while trasferring potential hardware 958 * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit. 959 */ 960 #define __HAVE_ARCH_PTEP_SET_WRPROTECT 961 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep) 962 { 963 pte_t old_pte, pte; 964 965 pte = READ_ONCE(*ptep); 966 do { 967 old_pte = pte; 968 pte = pte_wrprotect(pte); 969 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep), 970 pte_val(old_pte), pte_val(pte)); 971 } while (pte_val(pte) != pte_val(old_pte)); 972 } 973 974 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 975 #define __HAVE_ARCH_PMDP_SET_WRPROTECT 976 static inline void pmdp_set_wrprotect(struct mm_struct *mm, 977 unsigned long address, pmd_t *pmdp) 978 { 979 ptep_set_wrprotect(mm, address, (pte_t *)pmdp); 980 } 981 982 #define pmdp_establish pmdp_establish 983 static inline pmd_t pmdp_establish(struct vm_area_struct *vma, 984 unsigned long address, pmd_t *pmdp, pmd_t pmd) 985 { 986 page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd); 987 return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd))); 988 } 989 #endif 990 991 /* 992 * Encode and decode a swap entry: 993 * bits 0-1: present (must be zero) 994 * bits 2: remember PG_anon_exclusive 995 * bits 3-7: swap type 996 * bits 8-57: swap offset 997 * bit 58: PTE_PROT_NONE (must be zero) 998 */ 999 #define __SWP_TYPE_SHIFT 3 1000 #define __SWP_TYPE_BITS 5 1001 #define __SWP_OFFSET_BITS 50 1002 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1) 1003 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT) 1004 #define __SWP_OFFSET_MASK ((1UL << __SWP_OFFSET_BITS) - 1) 1005 1006 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK) 1007 #define __swp_offset(x) (((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK) 1008 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) }) 1009 1010 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 1011 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 1012 1013 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1014 #define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) }) 1015 #define __swp_entry_to_pmd(swp) __pmd((swp).val) 1016 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */ 1017 1018 /* 1019 * Ensure that there are not more swap files than can be encoded in the kernel 1020 * PTEs. 1021 */ 1022 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS) 1023 1024 extern int kern_addr_valid(unsigned long addr); 1025 1026 #ifdef CONFIG_ARM64_MTE 1027 1028 #define __HAVE_ARCH_PREPARE_TO_SWAP 1029 static inline int arch_prepare_to_swap(struct page *page) 1030 { 1031 if (system_supports_mte()) 1032 return mte_save_tags(page); 1033 return 0; 1034 } 1035 1036 #define __HAVE_ARCH_SWAP_INVALIDATE 1037 static inline void arch_swap_invalidate_page(int type, pgoff_t offset) 1038 { 1039 if (system_supports_mte()) 1040 mte_invalidate_tags(type, offset); 1041 } 1042 1043 static inline void arch_swap_invalidate_area(int type) 1044 { 1045 if (system_supports_mte()) 1046 mte_invalidate_tags_area(type); 1047 } 1048 1049 #define __HAVE_ARCH_SWAP_RESTORE 1050 static inline void arch_swap_restore(swp_entry_t entry, struct folio *folio) 1051 { 1052 if (system_supports_mte() && mte_restore_tags(entry, &folio->page)) 1053 set_bit(PG_mte_tagged, &folio->flags); 1054 } 1055 1056 #endif /* CONFIG_ARM64_MTE */ 1057 1058 /* 1059 * On AArch64, the cache coherency is handled via the set_pte_at() function. 1060 */ 1061 static inline void update_mmu_cache(struct vm_area_struct *vma, 1062 unsigned long addr, pte_t *ptep) 1063 { 1064 /* 1065 * We don't do anything here, so there's a very small chance of 1066 * us retaking a user fault which we just fixed up. The alternative 1067 * is doing a dsb(ishst), but that penalises the fastpath. 1068 */ 1069 } 1070 1071 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0) 1072 1073 #ifdef CONFIG_ARM64_PA_BITS_52 1074 #define phys_to_ttbr(addr) (((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52) 1075 #else 1076 #define phys_to_ttbr(addr) (addr) 1077 #endif 1078 1079 /* 1080 * On arm64 without hardware Access Flag, copying from user will fail because 1081 * the pte is old and cannot be marked young. So we always end up with zeroed 1082 * page after fork() + CoW for pfn mappings. We don't always have a 1083 * hardware-managed access flag on arm64. 1084 */ 1085 static inline bool arch_faults_on_old_pte(void) 1086 { 1087 /* The register read below requires a stable CPU to make any sense */ 1088 cant_migrate(); 1089 1090 return !cpu_has_hw_af(); 1091 } 1092 #define arch_faults_on_old_pte arch_faults_on_old_pte 1093 1094 /* 1095 * Experimentally, it's cheap to set the access flag in hardware and we 1096 * benefit from prefaulting mappings as 'old' to start with. 1097 */ 1098 static inline bool arch_wants_old_prefaulted_pte(void) 1099 { 1100 return !arch_faults_on_old_pte(); 1101 } 1102 #define arch_wants_old_prefaulted_pte arch_wants_old_prefaulted_pte 1103 1104 static inline bool pud_sect_supported(void) 1105 { 1106 return PAGE_SIZE == SZ_4K; 1107 } 1108 1109 1110 #endif /* !__ASSEMBLY__ */ 1111 1112 #endif /* __ASM_PGTABLE_H */ 1113