1 /* 2 * Copyright (C) 2012 ARM Ltd. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 #ifndef __ASM_PGTABLE_H 17 #define __ASM_PGTABLE_H 18 19 #include <asm/bug.h> 20 #include <asm/proc-fns.h> 21 22 #include <asm/memory.h> 23 #include <asm/pgtable-hwdef.h> 24 #include <asm/pgtable-prot.h> 25 26 /* 27 * VMALLOC range. 28 * 29 * VMALLOC_START: beginning of the kernel vmalloc space 30 * VMALLOC_END: extends to the available space below vmmemmap, PCI I/O space 31 * and fixed mappings 32 */ 33 #define VMALLOC_START (MODULES_END) 34 #define VMALLOC_END (PAGE_OFFSET - PUD_SIZE - VMEMMAP_SIZE - SZ_64K) 35 36 #define vmemmap ((struct page *)VMEMMAP_START - (memstart_addr >> PAGE_SHIFT)) 37 38 #define FIRST_USER_ADDRESS 0UL 39 40 #ifndef __ASSEMBLY__ 41 42 #include <asm/cmpxchg.h> 43 #include <asm/fixmap.h> 44 #include <linux/mmdebug.h> 45 #include <linux/mm_types.h> 46 #include <linux/sched.h> 47 48 extern void __pte_error(const char *file, int line, unsigned long val); 49 extern void __pmd_error(const char *file, int line, unsigned long val); 50 extern void __pud_error(const char *file, int line, unsigned long val); 51 extern void __pgd_error(const char *file, int line, unsigned long val); 52 53 /* 54 * ZERO_PAGE is a global shared page that is always zero: used 55 * for zero-mapped memory areas etc.. 56 */ 57 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; 58 #define ZERO_PAGE(vaddr) phys_to_page(__pa_symbol(empty_zero_page)) 59 60 #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte)) 61 62 /* 63 * Macros to convert between a physical address and its placement in a 64 * page table entry, taking care of 52-bit addresses. 65 */ 66 #ifdef CONFIG_ARM64_PA_BITS_52 67 #define __pte_to_phys(pte) \ 68 ((pte_val(pte) & PTE_ADDR_LOW) | ((pte_val(pte) & PTE_ADDR_HIGH) << 36)) 69 #define __phys_to_pte_val(phys) (((phys) | ((phys) >> 36)) & PTE_ADDR_MASK) 70 #else 71 #define __pte_to_phys(pte) (pte_val(pte) & PTE_ADDR_MASK) 72 #define __phys_to_pte_val(phys) (phys) 73 #endif 74 75 #define pte_pfn(pte) (__pte_to_phys(pte) >> PAGE_SHIFT) 76 #define pfn_pte(pfn,prot) \ 77 __pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 78 79 #define pte_none(pte) (!pte_val(pte)) 80 #define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0)) 81 #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) 82 83 /* 84 * The following only work if pte_present(). Undefined behaviour otherwise. 85 */ 86 #define pte_present(pte) (!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE))) 87 #define pte_young(pte) (!!(pte_val(pte) & PTE_AF)) 88 #define pte_special(pte) (!!(pte_val(pte) & PTE_SPECIAL)) 89 #define pte_write(pte) (!!(pte_val(pte) & PTE_WRITE)) 90 #define pte_user_exec(pte) (!(pte_val(pte) & PTE_UXN)) 91 #define pte_cont(pte) (!!(pte_val(pte) & PTE_CONT)) 92 93 #define pte_cont_addr_end(addr, end) \ 94 ({ unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK; \ 95 (__boundary - 1 < (end) - 1) ? __boundary : (end); \ 96 }) 97 98 #define pmd_cont_addr_end(addr, end) \ 99 ({ unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK; \ 100 (__boundary - 1 < (end) - 1) ? __boundary : (end); \ 101 }) 102 103 #define pte_hw_dirty(pte) (pte_write(pte) && !(pte_val(pte) & PTE_RDONLY)) 104 #define pte_sw_dirty(pte) (!!(pte_val(pte) & PTE_DIRTY)) 105 #define pte_dirty(pte) (pte_sw_dirty(pte) || pte_hw_dirty(pte)) 106 107 #define pte_valid(pte) (!!(pte_val(pte) & PTE_VALID)) 108 /* 109 * Execute-only user mappings do not have the PTE_USER bit set. All valid 110 * kernel mappings have the PTE_UXN bit set. 111 */ 112 #define pte_valid_not_user(pte) \ 113 ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN)) 114 #define pte_valid_young(pte) \ 115 ((pte_val(pte) & (PTE_VALID | PTE_AF)) == (PTE_VALID | PTE_AF)) 116 #define pte_valid_user(pte) \ 117 ((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) 118 119 /* 120 * Could the pte be present in the TLB? We must check mm_tlb_flush_pending 121 * so that we don't erroneously return false for pages that have been 122 * remapped as PROT_NONE but are yet to be flushed from the TLB. 123 */ 124 #define pte_accessible(mm, pte) \ 125 (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid_young(pte)) 126 127 /* 128 * p??_access_permitted() is true for valid user mappings (subject to the 129 * write permission check) other than user execute-only which do not have the 130 * PTE_USER bit set. PROT_NONE mappings do not have the PTE_VALID bit set. 131 */ 132 #define pte_access_permitted(pte, write) \ 133 (pte_valid_user(pte) && (!(write) || pte_write(pte))) 134 #define pmd_access_permitted(pmd, write) \ 135 (pte_access_permitted(pmd_pte(pmd), (write))) 136 #define pud_access_permitted(pud, write) \ 137 (pte_access_permitted(pud_pte(pud), (write))) 138 139 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot) 140 { 141 pte_val(pte) &= ~pgprot_val(prot); 142 return pte; 143 } 144 145 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot) 146 { 147 pte_val(pte) |= pgprot_val(prot); 148 return pte; 149 } 150 151 static inline pte_t pte_wrprotect(pte_t pte) 152 { 153 pte = clear_pte_bit(pte, __pgprot(PTE_WRITE)); 154 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY)); 155 return pte; 156 } 157 158 static inline pte_t pte_mkwrite(pte_t pte) 159 { 160 pte = set_pte_bit(pte, __pgprot(PTE_WRITE)); 161 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY)); 162 return pte; 163 } 164 165 static inline pte_t pte_mkclean(pte_t pte) 166 { 167 pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY)); 168 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY)); 169 170 return pte; 171 } 172 173 static inline pte_t pte_mkdirty(pte_t pte) 174 { 175 pte = set_pte_bit(pte, __pgprot(PTE_DIRTY)); 176 177 if (pte_write(pte)) 178 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY)); 179 180 return pte; 181 } 182 183 static inline pte_t pte_mkold(pte_t pte) 184 { 185 return clear_pte_bit(pte, __pgprot(PTE_AF)); 186 } 187 188 static inline pte_t pte_mkyoung(pte_t pte) 189 { 190 return set_pte_bit(pte, __pgprot(PTE_AF)); 191 } 192 193 static inline pte_t pte_mkspecial(pte_t pte) 194 { 195 return set_pte_bit(pte, __pgprot(PTE_SPECIAL)); 196 } 197 198 static inline pte_t pte_mkcont(pte_t pte) 199 { 200 pte = set_pte_bit(pte, __pgprot(PTE_CONT)); 201 return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE)); 202 } 203 204 static inline pte_t pte_mknoncont(pte_t pte) 205 { 206 return clear_pte_bit(pte, __pgprot(PTE_CONT)); 207 } 208 209 static inline pte_t pte_mkpresent(pte_t pte) 210 { 211 return set_pte_bit(pte, __pgprot(PTE_VALID)); 212 } 213 214 static inline pmd_t pmd_mkcont(pmd_t pmd) 215 { 216 return __pmd(pmd_val(pmd) | PMD_SECT_CONT); 217 } 218 219 static inline void set_pte(pte_t *ptep, pte_t pte) 220 { 221 WRITE_ONCE(*ptep, pte); 222 223 /* 224 * Only if the new pte is valid and kernel, otherwise TLB maintenance 225 * or update_mmu_cache() have the necessary barriers. 226 */ 227 if (pte_valid_not_user(pte)) { 228 dsb(ishst); 229 isb(); 230 } 231 } 232 233 extern void __sync_icache_dcache(pte_t pteval); 234 235 /* 236 * PTE bits configuration in the presence of hardware Dirty Bit Management 237 * (PTE_WRITE == PTE_DBM): 238 * 239 * Dirty Writable | PTE_RDONLY PTE_WRITE PTE_DIRTY (sw) 240 * 0 0 | 1 0 0 241 * 0 1 | 1 1 0 242 * 1 0 | 1 0 1 243 * 1 1 | 0 1 x 244 * 245 * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via 246 * the page fault mechanism. Checking the dirty status of a pte becomes: 247 * 248 * PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY) 249 */ 250 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 251 pte_t *ptep, pte_t pte) 252 { 253 pte_t old_pte; 254 255 if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte)) 256 __sync_icache_dcache(pte); 257 258 /* 259 * If the existing pte is valid, check for potential race with 260 * hardware updates of the pte (ptep_set_access_flags safely changes 261 * valid ptes without going through an invalid entry). 262 */ 263 old_pte = READ_ONCE(*ptep); 264 if (IS_ENABLED(CONFIG_DEBUG_VM) && pte_valid(old_pte) && pte_valid(pte) && 265 (mm == current->active_mm || atomic_read(&mm->mm_users) > 1)) { 266 VM_WARN_ONCE(!pte_young(pte), 267 "%s: racy access flag clearing: 0x%016llx -> 0x%016llx", 268 __func__, pte_val(old_pte), pte_val(pte)); 269 VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte), 270 "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx", 271 __func__, pte_val(old_pte), pte_val(pte)); 272 } 273 274 set_pte(ptep, pte); 275 } 276 277 #define __HAVE_ARCH_PTE_SAME 278 static inline int pte_same(pte_t pte_a, pte_t pte_b) 279 { 280 pteval_t lhs, rhs; 281 282 lhs = pte_val(pte_a); 283 rhs = pte_val(pte_b); 284 285 if (pte_present(pte_a)) 286 lhs &= ~PTE_RDONLY; 287 288 if (pte_present(pte_b)) 289 rhs &= ~PTE_RDONLY; 290 291 return (lhs == rhs); 292 } 293 294 /* 295 * Huge pte definitions. 296 */ 297 #define pte_huge(pte) (!(pte_val(pte) & PTE_TABLE_BIT)) 298 #define pte_mkhuge(pte) (__pte(pte_val(pte) & ~PTE_TABLE_BIT)) 299 300 /* 301 * Hugetlb definitions. 302 */ 303 #define HUGE_MAX_HSTATE 4 304 #define HPAGE_SHIFT PMD_SHIFT 305 #define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT) 306 #define HPAGE_MASK (~(HPAGE_SIZE - 1)) 307 #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT) 308 309 static inline pte_t pgd_pte(pgd_t pgd) 310 { 311 return __pte(pgd_val(pgd)); 312 } 313 314 static inline pte_t pud_pte(pud_t pud) 315 { 316 return __pte(pud_val(pud)); 317 } 318 319 static inline pmd_t pud_pmd(pud_t pud) 320 { 321 return __pmd(pud_val(pud)); 322 } 323 324 static inline pte_t pmd_pte(pmd_t pmd) 325 { 326 return __pte(pmd_val(pmd)); 327 } 328 329 static inline pmd_t pte_pmd(pte_t pte) 330 { 331 return __pmd(pte_val(pte)); 332 } 333 334 static inline pgprot_t mk_sect_prot(pgprot_t prot) 335 { 336 return __pgprot(pgprot_val(prot) & ~PTE_TABLE_BIT); 337 } 338 339 #ifdef CONFIG_NUMA_BALANCING 340 /* 341 * See the comment in include/asm-generic/pgtable.h 342 */ 343 static inline int pte_protnone(pte_t pte) 344 { 345 return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE; 346 } 347 348 static inline int pmd_protnone(pmd_t pmd) 349 { 350 return pte_protnone(pmd_pte(pmd)); 351 } 352 #endif 353 354 /* 355 * THP definitions. 356 */ 357 358 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 359 #define pmd_trans_huge(pmd) (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT)) 360 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 361 362 #define pmd_present(pmd) pte_present(pmd_pte(pmd)) 363 #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd)) 364 #define pmd_young(pmd) pte_young(pmd_pte(pmd)) 365 #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd))) 366 #define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd))) 367 #define pmd_mkwrite(pmd) pte_pmd(pte_mkwrite(pmd_pte(pmd))) 368 #define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd))) 369 #define pmd_mkdirty(pmd) pte_pmd(pte_mkdirty(pmd_pte(pmd))) 370 #define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd))) 371 #define pmd_mknotpresent(pmd) (__pmd(pmd_val(pmd) & ~PMD_SECT_VALID)) 372 373 #define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd)) 374 375 #define pmd_write(pmd) pte_write(pmd_pte(pmd)) 376 377 #define pmd_mkhuge(pmd) (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT)) 378 379 #define __pmd_to_phys(pmd) __pte_to_phys(pmd_pte(pmd)) 380 #define __phys_to_pmd_val(phys) __phys_to_pte_val(phys) 381 #define pmd_pfn(pmd) ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT) 382 #define pfn_pmd(pfn,prot) __pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 383 #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot) 384 385 #define pud_write(pud) pte_write(pud_pte(pud)) 386 387 #define __pud_to_phys(pud) __pte_to_phys(pud_pte(pud)) 388 #define __phys_to_pud_val(phys) __phys_to_pte_val(phys) 389 #define pud_pfn(pud) ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT) 390 #define pfn_pud(pfn,prot) __pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) 391 392 #define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd)) 393 394 #define __pgd_to_phys(pgd) __pte_to_phys(pgd_pte(pgd)) 395 #define __phys_to_pgd_val(phys) __phys_to_pte_val(phys) 396 397 #define __pgprot_modify(prot,mask,bits) \ 398 __pgprot((pgprot_val(prot) & ~(mask)) | (bits)) 399 400 /* 401 * Mark the prot value as uncacheable and unbufferable. 402 */ 403 #define pgprot_noncached(prot) \ 404 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN) 405 #define pgprot_writecombine(prot) \ 406 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN) 407 #define pgprot_device(prot) \ 408 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN) 409 #define __HAVE_PHYS_MEM_ACCESS_PROT 410 struct file; 411 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 412 unsigned long size, pgprot_t vma_prot); 413 414 #define pmd_none(pmd) (!pmd_val(pmd)) 415 416 #define pmd_bad(pmd) (!(pmd_val(pmd) & PMD_TABLE_BIT)) 417 418 #define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ 419 PMD_TYPE_TABLE) 420 #define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ 421 PMD_TYPE_SECT) 422 423 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3 424 #define pud_sect(pud) (0) 425 #define pud_table(pud) (1) 426 #else 427 #define pud_sect(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \ 428 PUD_TYPE_SECT) 429 #define pud_table(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \ 430 PUD_TYPE_TABLE) 431 #endif 432 433 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd) 434 { 435 WRITE_ONCE(*pmdp, pmd); 436 dsb(ishst); 437 isb(); 438 } 439 440 static inline void pmd_clear(pmd_t *pmdp) 441 { 442 set_pmd(pmdp, __pmd(0)); 443 } 444 445 static inline phys_addr_t pmd_page_paddr(pmd_t pmd) 446 { 447 return __pmd_to_phys(pmd); 448 } 449 450 /* Find an entry in the third-level page table. */ 451 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) 452 453 #define pte_offset_phys(dir,addr) (pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t)) 454 #define pte_offset_kernel(dir,addr) ((pte_t *)__va(pte_offset_phys((dir), (addr)))) 455 456 #define pte_offset_map(dir,addr) pte_offset_kernel((dir), (addr)) 457 #define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr)) 458 #define pte_unmap(pte) do { } while (0) 459 #define pte_unmap_nested(pte) do { } while (0) 460 461 #define pte_set_fixmap(addr) ((pte_t *)set_fixmap_offset(FIX_PTE, addr)) 462 #define pte_set_fixmap_offset(pmd, addr) pte_set_fixmap(pte_offset_phys(pmd, addr)) 463 #define pte_clear_fixmap() clear_fixmap(FIX_PTE) 464 465 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(__pmd_to_phys(pmd))) 466 467 /* use ONLY for statically allocated translation tables */ 468 #define pte_offset_kimg(dir,addr) ((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr)))) 469 470 /* 471 * Conversion functions: convert a page and protection to a page entry, 472 * and a page entry and page directory to the page they refer to. 473 */ 474 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page),prot) 475 476 #if CONFIG_PGTABLE_LEVELS > 2 477 478 #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd)) 479 480 #define pud_none(pud) (!pud_val(pud)) 481 #define pud_bad(pud) (!(pud_val(pud) & PUD_TABLE_BIT)) 482 #define pud_present(pud) pte_present(pud_pte(pud)) 483 484 static inline void set_pud(pud_t *pudp, pud_t pud) 485 { 486 WRITE_ONCE(*pudp, pud); 487 dsb(ishst); 488 isb(); 489 } 490 491 static inline void pud_clear(pud_t *pudp) 492 { 493 set_pud(pudp, __pud(0)); 494 } 495 496 static inline phys_addr_t pud_page_paddr(pud_t pud) 497 { 498 return __pud_to_phys(pud); 499 } 500 501 /* Find an entry in the second-level page table. */ 502 #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) 503 504 #define pmd_offset_phys(dir, addr) (pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t)) 505 #define pmd_offset(dir, addr) ((pmd_t *)__va(pmd_offset_phys((dir), (addr)))) 506 507 #define pmd_set_fixmap(addr) ((pmd_t *)set_fixmap_offset(FIX_PMD, addr)) 508 #define pmd_set_fixmap_offset(pud, addr) pmd_set_fixmap(pmd_offset_phys(pud, addr)) 509 #define pmd_clear_fixmap() clear_fixmap(FIX_PMD) 510 511 #define pud_page(pud) pfn_to_page(__phys_to_pfn(__pud_to_phys(pud))) 512 513 /* use ONLY for statically allocated translation tables */ 514 #define pmd_offset_kimg(dir,addr) ((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr)))) 515 516 #else 517 518 #define pud_page_paddr(pud) ({ BUILD_BUG(); 0; }) 519 520 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */ 521 #define pmd_set_fixmap(addr) NULL 522 #define pmd_set_fixmap_offset(pudp, addr) ((pmd_t *)pudp) 523 #define pmd_clear_fixmap() 524 525 #define pmd_offset_kimg(dir,addr) ((pmd_t *)dir) 526 527 #endif /* CONFIG_PGTABLE_LEVELS > 2 */ 528 529 #if CONFIG_PGTABLE_LEVELS > 3 530 531 #define pud_ERROR(pud) __pud_error(__FILE__, __LINE__, pud_val(pud)) 532 533 #define pgd_none(pgd) (!pgd_val(pgd)) 534 #define pgd_bad(pgd) (!(pgd_val(pgd) & 2)) 535 #define pgd_present(pgd) (pgd_val(pgd)) 536 537 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd) 538 { 539 WRITE_ONCE(*pgdp, pgd); 540 dsb(ishst); 541 } 542 543 static inline void pgd_clear(pgd_t *pgdp) 544 { 545 set_pgd(pgdp, __pgd(0)); 546 } 547 548 static inline phys_addr_t pgd_page_paddr(pgd_t pgd) 549 { 550 return __pgd_to_phys(pgd); 551 } 552 553 /* Find an entry in the frst-level page table. */ 554 #define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1)) 555 556 #define pud_offset_phys(dir, addr) (pgd_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t)) 557 #define pud_offset(dir, addr) ((pud_t *)__va(pud_offset_phys((dir), (addr)))) 558 559 #define pud_set_fixmap(addr) ((pud_t *)set_fixmap_offset(FIX_PUD, addr)) 560 #define pud_set_fixmap_offset(pgd, addr) pud_set_fixmap(pud_offset_phys(pgd, addr)) 561 #define pud_clear_fixmap() clear_fixmap(FIX_PUD) 562 563 #define pgd_page(pgd) pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd))) 564 565 /* use ONLY for statically allocated translation tables */ 566 #define pud_offset_kimg(dir,addr) ((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr)))) 567 568 #else 569 570 #define pgd_page_paddr(pgd) ({ BUILD_BUG(); 0;}) 571 572 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */ 573 #define pud_set_fixmap(addr) NULL 574 #define pud_set_fixmap_offset(pgdp, addr) ((pud_t *)pgdp) 575 #define pud_clear_fixmap() 576 577 #define pud_offset_kimg(dir,addr) ((pud_t *)dir) 578 579 #endif /* CONFIG_PGTABLE_LEVELS > 3 */ 580 581 #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd)) 582 583 /* to find an entry in a page-table-directory */ 584 #define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)) 585 586 #define pgd_offset_raw(pgd, addr) ((pgd) + pgd_index(addr)) 587 588 #define pgd_offset(mm, addr) (pgd_offset_raw((mm)->pgd, (addr))) 589 590 /* to find an entry in a kernel page-table-directory */ 591 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) 592 593 #define pgd_set_fixmap(addr) ((pgd_t *)set_fixmap_offset(FIX_PGD, addr)) 594 #define pgd_clear_fixmap() clear_fixmap(FIX_PGD) 595 596 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 597 { 598 const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY | 599 PTE_PROT_NONE | PTE_VALID | PTE_WRITE; 600 /* preserve the hardware dirty information */ 601 if (pte_hw_dirty(pte)) 602 pte = pte_mkdirty(pte); 603 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 604 return pte; 605 } 606 607 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) 608 { 609 return pte_pmd(pte_modify(pmd_pte(pmd), newprot)); 610 } 611 612 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS 613 extern int ptep_set_access_flags(struct vm_area_struct *vma, 614 unsigned long address, pte_t *ptep, 615 pte_t entry, int dirty); 616 617 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 618 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS 619 static inline int pmdp_set_access_flags(struct vm_area_struct *vma, 620 unsigned long address, pmd_t *pmdp, 621 pmd_t entry, int dirty) 622 { 623 return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty); 624 } 625 #endif 626 627 /* 628 * Atomic pte/pmd modifications. 629 */ 630 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG 631 static inline int __ptep_test_and_clear_young(pte_t *ptep) 632 { 633 pte_t old_pte, pte; 634 635 pte = READ_ONCE(*ptep); 636 do { 637 old_pte = pte; 638 pte = pte_mkold(pte); 639 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep), 640 pte_val(old_pte), pte_val(pte)); 641 } while (pte_val(pte) != pte_val(old_pte)); 642 643 return pte_young(pte); 644 } 645 646 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, 647 unsigned long address, 648 pte_t *ptep) 649 { 650 return __ptep_test_and_clear_young(ptep); 651 } 652 653 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 654 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG 655 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, 656 unsigned long address, 657 pmd_t *pmdp) 658 { 659 return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp); 660 } 661 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 662 663 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR 664 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, 665 unsigned long address, pte_t *ptep) 666 { 667 return __pte(xchg_relaxed(&pte_val(*ptep), 0)); 668 } 669 670 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 671 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR 672 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, 673 unsigned long address, pmd_t *pmdp) 674 { 675 return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp)); 676 } 677 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 678 679 /* 680 * ptep_set_wrprotect - mark read-only while trasferring potential hardware 681 * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit. 682 */ 683 #define __HAVE_ARCH_PTEP_SET_WRPROTECT 684 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep) 685 { 686 pte_t old_pte, pte; 687 688 pte = READ_ONCE(*ptep); 689 do { 690 old_pte = pte; 691 /* 692 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY 693 * clear), set the PTE_DIRTY bit. 694 */ 695 if (pte_hw_dirty(pte)) 696 pte = pte_mkdirty(pte); 697 pte = pte_wrprotect(pte); 698 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep), 699 pte_val(old_pte), pte_val(pte)); 700 } while (pte_val(pte) != pte_val(old_pte)); 701 } 702 703 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 704 #define __HAVE_ARCH_PMDP_SET_WRPROTECT 705 static inline void pmdp_set_wrprotect(struct mm_struct *mm, 706 unsigned long address, pmd_t *pmdp) 707 { 708 ptep_set_wrprotect(mm, address, (pte_t *)pmdp); 709 } 710 711 #define pmdp_establish pmdp_establish 712 static inline pmd_t pmdp_establish(struct vm_area_struct *vma, 713 unsigned long address, pmd_t *pmdp, pmd_t pmd) 714 { 715 return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd))); 716 } 717 #endif 718 719 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 720 extern pgd_t swapper_pg_end[]; 721 extern pgd_t idmap_pg_dir[PTRS_PER_PGD]; 722 extern pgd_t tramp_pg_dir[PTRS_PER_PGD]; 723 724 /* 725 * Encode and decode a swap entry: 726 * bits 0-1: present (must be zero) 727 * bits 2-7: swap type 728 * bits 8-57: swap offset 729 * bit 58: PTE_PROT_NONE (must be zero) 730 */ 731 #define __SWP_TYPE_SHIFT 2 732 #define __SWP_TYPE_BITS 6 733 #define __SWP_OFFSET_BITS 50 734 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1) 735 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT) 736 #define __SWP_OFFSET_MASK ((1UL << __SWP_OFFSET_BITS) - 1) 737 738 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK) 739 #define __swp_offset(x) (((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK) 740 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) }) 741 742 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 743 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 744 745 /* 746 * Ensure that there are not more swap files than can be encoded in the kernel 747 * PTEs. 748 */ 749 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS) 750 751 extern int kern_addr_valid(unsigned long addr); 752 753 #include <asm-generic/pgtable.h> 754 755 void pgd_cache_init(void); 756 #define pgtable_cache_init pgd_cache_init 757 758 /* 759 * On AArch64, the cache coherency is handled via the set_pte_at() function. 760 */ 761 static inline void update_mmu_cache(struct vm_area_struct *vma, 762 unsigned long addr, pte_t *ptep) 763 { 764 /* 765 * We don't do anything here, so there's a very small chance of 766 * us retaking a user fault which we just fixed up. The alternative 767 * is doing a dsb(ishst), but that penalises the fastpath. 768 */ 769 } 770 771 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0) 772 773 #define kc_vaddr_to_offset(v) ((v) & ~VA_START) 774 #define kc_offset_to_vaddr(o) ((o) | VA_START) 775 776 #ifdef CONFIG_ARM64_PA_BITS_52 777 #define phys_to_ttbr(addr) (((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52) 778 #else 779 #define phys_to_ttbr(addr) (addr) 780 #endif 781 782 #endif /* !__ASSEMBLY__ */ 783 784 #endif /* __ASM_PGTABLE_H */ 785