arch/arm64/include/asm/pgtable.h

   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
  25 /*
  26  * Software defined PTE bits definition.
  27  */
  28 #define PTE_VALID               (_AT(pteval_t, 1) << 0)
  29 #define PTE_WRITE               (PTE_DBM)                /* same as DBM (51) */
  30 #define PTE_DIRTY               (_AT(pteval_t, 1) << 55)
  31 #define PTE_SPECIAL             (_AT(pteval_t, 1) << 56)
  32 #define PTE_PROT_NONE           (_AT(pteval_t, 1) << 58) /* only when !PTE_VALID */
  33
  34 /*
  35  * VMALLOC and SPARSEMEM_VMEMMAP ranges.
  36  *
  37  * VMEMAP_SIZE: allows the whole VA space to be covered by a struct page array
  38  *      (rounded up to PUD_SIZE).
  39  * VMALLOC_START: beginning of the kernel VA space
  40  * VMALLOC_END: extends to the available space below vmmemmap, PCI I/O space,
  41  *      fixed mappings and modules
  42  */
  43 #define VMEMMAP_SIZE            ALIGN((1UL << (VA_BITS - PAGE_SHIFT)) * sizeof(struct page), PUD_SIZE)
  44
  45 #ifndef CONFIG_KASAN
  46 #define VMALLOC_START           (VA_START)
  47 #else
  48 #include <asm/kasan.h>
  49 #define VMALLOC_START           (KASAN_SHADOW_END + SZ_64K)
  50 #endif
  51
  52 #define VMALLOC_END             (PAGE_OFFSET - PUD_SIZE - VMEMMAP_SIZE - SZ_64K)
  53
  54 #define vmemmap                 ((struct page *)(VMALLOC_END + SZ_64K))
  55
  56 #define FIRST_USER_ADDRESS      0UL
  57
  58 #ifndef __ASSEMBLY__
  59
  60 #include <linux/mmdebug.h>
  61
  62 extern void __pte_error(const char *file, int line, unsigned long val);
  63 extern void __pmd_error(const char *file, int line, unsigned long val);
  64 extern void __pud_error(const char *file, int line, unsigned long val);
  65 extern void __pgd_error(const char *file, int line, unsigned long val);
  66
  67 #define PROT_DEFAULT            (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
  68 #define PROT_SECT_DEFAULT       (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
  69
  70 #define PROT_DEVICE_nGnRnE      (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_DEVICE_nGnRnE))
  71 #define PROT_DEVICE_nGnRE       (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_DEVICE_nGnRE))
  72 #define PROT_NORMAL_NC          (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_NORMAL_NC))
  73 #define PROT_NORMAL_WT          (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_NORMAL_WT))
  74 #define PROT_NORMAL             (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_NORMAL))
  75
  76 #define PROT_SECT_DEVICE_nGnRE  (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE))
  77 #define PROT_SECT_NORMAL        (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
  78 #define PROT_SECT_NORMAL_EXEC   (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
  79
  80 #define _PAGE_DEFAULT           (PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL))
  81
  82 #define PAGE_KERNEL             __pgprot(_PAGE_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_WRITE)
  83 #define PAGE_KERNEL_RO          __pgprot(_PAGE_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_RDONLY)
  84 #define PAGE_KERNEL_ROX __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_RDONLY)
  85 #define PAGE_KERNEL_EXEC        __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE)
  86 #define PAGE_KERNEL_EXEC_CONT   __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE | PTE_CONT)
  87
  88 #define PAGE_HYP                __pgprot(_PAGE_DEFAULT | PTE_HYP)
  89 #define PAGE_HYP_DEVICE         __pgprot(PROT_DEVICE_nGnRE | PTE_HYP)
  90
  91 #define PAGE_S2                 __pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_NORMAL) | PTE_S2_RDONLY)
  92 #define PAGE_S2_DEVICE          __pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_DEVICE_nGnRE) | PTE_S2_RDONLY | PTE_UXN)
  93
  94 #define PAGE_NONE               __pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_PXN | PTE_UXN)
  95 #define PAGE_SHARED             __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE)
  96 #define PAGE_SHARED_EXEC        __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_WRITE)
  97 #define PAGE_COPY               __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
  98 #define PAGE_COPY_EXEC          __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN)
  99 #define PAGE_READONLY           __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
 100 #define PAGE_READONLY_EXEC      __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN)
 101
 102 #define __P000  PAGE_NONE
 103 #define __P001  PAGE_READONLY
 104 #define __P010  PAGE_COPY
 105 #define __P011  PAGE_COPY
 106 #define __P100  PAGE_READONLY_EXEC
 107 #define __P101  PAGE_READONLY_EXEC
 108 #define __P110  PAGE_COPY_EXEC
 109 #define __P111  PAGE_COPY_EXEC
 110
 111 #define __S000  PAGE_NONE
 112 #define __S001  PAGE_READONLY
 113 #define __S010  PAGE_SHARED
 114 #define __S011  PAGE_SHARED
 115 #define __S100  PAGE_READONLY_EXEC
 116 #define __S101  PAGE_READONLY_EXEC
 117 #define __S110  PAGE_SHARED_EXEC
 118 #define __S111  PAGE_SHARED_EXEC
 119
 120 /*
 121  * ZERO_PAGE is a global shared page that is always zero: used
 122  * for zero-mapped memory areas etc..
 123  */
 124 extern struct page *empty_zero_page;
 125 #define ZERO_PAGE(vaddr)        (empty_zero_page)
 126
 127 #define pte_ERROR(pte)          __pte_error(__FILE__, __LINE__, pte_val(pte))
 128
 129 #define pte_pfn(pte)            ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
 130
 131 #define pfn_pte(pfn,prot)       (__pte(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
 132
 133 #define pte_none(pte)           (!pte_val(pte))
 134 #define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0))
 135 #define pte_page(pte)           (pfn_to_page(pte_pfn(pte)))
 136
 137 /* Find an entry in the third-level page table. */
 138 #define pte_index(addr)         (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 139
 140 #define pte_offset_kernel(dir,addr)     (pmd_page_vaddr(*(dir)) + pte_index(addr))
 141
 142 #define pte_offset_map(dir,addr)        pte_offset_kernel((dir), (addr))
 143 #define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr))
 144 #define pte_unmap(pte)                  do { } while (0)
 145 #define pte_unmap_nested(pte)           do { } while (0)
 146
 147 /*
 148  * The following only work if pte_present(). Undefined behaviour otherwise.
 149  */
 150 #define pte_present(pte)        (!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
 151 #define pte_young(pte)          (!!(pte_val(pte) & PTE_AF))
 152 #define pte_special(pte)        (!!(pte_val(pte) & PTE_SPECIAL))
 153 #define pte_write(pte)          (!!(pte_val(pte) & PTE_WRITE))
 154 #define pte_exec(pte)           (!(pte_val(pte) & PTE_UXN))
 155 #define pte_cont(pte)           (!!(pte_val(pte) & PTE_CONT))
 156
 157 #ifdef CONFIG_ARM64_HW_AFDBM
 158 #define pte_hw_dirty(pte)       (pte_write(pte) && !(pte_val(pte) & PTE_RDONLY))
 159 #else
 160 #define pte_hw_dirty(pte)       (0)
 161 #endif
 162 #define pte_sw_dirty(pte)       (!!(pte_val(pte) & PTE_DIRTY))
 163 #define pte_dirty(pte)          (pte_sw_dirty(pte) || pte_hw_dirty(pte))
 164
 165 #define pte_valid(pte)          (!!(pte_val(pte) & PTE_VALID))
 166 #define pte_valid_user(pte) \
 167         ((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER))
 168 #define pte_valid_not_user(pte) \
 169         ((pte_val(pte) & (PTE_VALID | PTE_USER)) == PTE_VALID)
 170 #define pte_valid_young(pte) \
 171         ((pte_val(pte) & (PTE_VALID | PTE_AF)) == (PTE_VALID | PTE_AF))
 172
 173 /*
 174  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
 175  * so that we don't erroneously return false for pages that have been
 176  * remapped as PROT_NONE but are yet to be flushed from the TLB.
 177  */
 178 #define pte_accessible(mm, pte) \
 179         (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid_young(pte))
 180
 181 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
 182 {
 183         pte_val(pte) &= ~pgprot_val(prot);
 184         return pte;
 185 }
 186
 187 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
 188 {
 189         pte_val(pte) |= pgprot_val(prot);
 190         return pte;
 191 }
 192
 193 static inline pte_t pte_wrprotect(pte_t pte)
 194 {
 195         return clear_pte_bit(pte, __pgprot(PTE_WRITE));
 196 }
 197
 198 static inline pte_t pte_mkwrite(pte_t pte)
 199 {
 200         return set_pte_bit(pte, __pgprot(PTE_WRITE));
 201 }
 202
 203 static inline pte_t pte_mkclean(pte_t pte)
 204 {
 205         return clear_pte_bit(pte, __pgprot(PTE_DIRTY));
 206 }
 207
 208 static inline pte_t pte_mkdirty(pte_t pte)
 209 {
 210         return set_pte_bit(pte, __pgprot(PTE_DIRTY));
 211 }
 212
 213 static inline pte_t pte_mkold(pte_t pte)
 214 {
 215         return clear_pte_bit(pte, __pgprot(PTE_AF));
 216 }
 217
 218 static inline pte_t pte_mkyoung(pte_t pte)
 219 {
 220         return set_pte_bit(pte, __pgprot(PTE_AF));
 221 }
 222
 223 static inline pte_t pte_mkspecial(pte_t pte)
 224 {
 225         return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
 226 }
 227
 228 static inline pte_t pte_mkcont(pte_t pte)
 229 {
 230         pte = set_pte_bit(pte, __pgprot(PTE_CONT));
 231         return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
 232 }
 233
 234 static inline pte_t pte_mknoncont(pte_t pte)
 235 {
 236         return clear_pte_bit(pte, __pgprot(PTE_CONT));
 237 }
 238
 239 static inline pmd_t pmd_mkcont(pmd_t pmd)
 240 {
 241         return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
 242 }
 243
 244 static inline void set_pte(pte_t *ptep, pte_t pte)
 245 {
 246         *ptep = pte;
 247
 248         /*
 249          * Only if the new pte is valid and kernel, otherwise TLB maintenance
 250          * or update_mmu_cache() have the necessary barriers.
 251          */
 252         if (pte_valid_not_user(pte)) {
 253                 dsb(ishst);
 254                 isb();
 255         }
 256 }
 257
 258 struct mm_struct;
 259 struct vm_area_struct;
 260
 261 extern void __sync_icache_dcache(pte_t pteval, unsigned long addr);
 262
 263 /*
 264  * PTE bits configuration in the presence of hardware Dirty Bit Management
 265  * (PTE_WRITE == PTE_DBM):
 266  *
 267  * Dirty  Writable | PTE_RDONLY  PTE_WRITE  PTE_DIRTY (sw)
 268  *   0      0      |   1           0          0
 269  *   0      1      |   1           1          0
 270  *   1      0      |   1           0          1
 271  *   1      1      |   0           1          x
 272  *
 273  * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
 274  * the page fault mechanism. Checking the dirty status of a pte becomes:
 275  *
 276  *   PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
 277  */
 278 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 279                               pte_t *ptep, pte_t pte)
 280 {
 281         if (pte_valid_user(pte)) {
 282                 if (!pte_special(pte) && pte_exec(pte))
 283                         __sync_icache_dcache(pte, addr);
 284                 if (pte_sw_dirty(pte) && pte_write(pte))
 285                         pte_val(pte) &= ~PTE_RDONLY;
 286                 else
 287                         pte_val(pte) |= PTE_RDONLY;
 288         }
 289
 290         /*
 291          * If the existing pte is valid, check for potential race with
 292          * hardware updates of the pte (ptep_set_access_flags safely changes
 293          * valid ptes without going through an invalid entry).
 294          */
 295         if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM) &&
 296             pte_valid(*ptep) && pte_valid(pte)) {
 297                 VM_WARN_ONCE(!pte_young(pte),
 298                              "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
 299                              __func__, pte_val(*ptep), pte_val(pte));
 300                 VM_WARN_ONCE(pte_write(*ptep) && !pte_dirty(pte),
 301                              "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
 302                              __func__, pte_val(*ptep), pte_val(pte));
 303         }
 304
 305         set_pte(ptep, pte);
 306 }
 307
 308 /*
 309  * Huge pte definitions.
 310  */
 311 #define pte_huge(pte)           (!(pte_val(pte) & PTE_TABLE_BIT))
 312 #define pte_mkhuge(pte)         (__pte(pte_val(pte) & ~PTE_TABLE_BIT))
 313
 314 /*
 315  * Hugetlb definitions.
 316  */
 317 #define HUGE_MAX_HSTATE         4
 318 #define HPAGE_SHIFT             PMD_SHIFT
 319 #define HPAGE_SIZE              (_AC(1, UL) << HPAGE_SHIFT)
 320 #define HPAGE_MASK              (~(HPAGE_SIZE - 1))
 321 #define HUGETLB_PAGE_ORDER      (HPAGE_SHIFT - PAGE_SHIFT)
 322
 323 #define __HAVE_ARCH_PTE_SPECIAL
 324
 325 static inline pte_t pud_pte(pud_t pud)
 326 {
 327         return __pte(pud_val(pud));
 328 }
 329
 330 static inline pmd_t pud_pmd(pud_t pud)
 331 {
 332         return __pmd(pud_val(pud));
 333 }
 334
 335 static inline pte_t pmd_pte(pmd_t pmd)
 336 {
 337         return __pte(pmd_val(pmd));
 338 }
 339
 340 static inline pmd_t pte_pmd(pte_t pte)
 341 {
 342         return __pmd(pte_val(pte));
 343 }
 344
 345 static inline pgprot_t mk_sect_prot(pgprot_t prot)
 346 {
 347         return __pgprot(pgprot_val(prot) & ~PTE_TABLE_BIT);
 348 }
 349
 350 /*
 351  * THP definitions.
 352  */
 353
 354 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 355 #define pmd_trans_huge(pmd)     (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT))
 356 #define pmd_trans_splitting(pmd)        pte_special(pmd_pte(pmd))
 357 #ifdef CONFIG_HAVE_RCU_TABLE_FREE
 358 #define __HAVE_ARCH_PMDP_SPLITTING_FLUSH
 359 struct vm_area_struct;
 360 void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
 361                           pmd_t *pmdp);
 362 #endif /* CONFIG_HAVE_RCU_TABLE_FREE */
 363 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 364
 365 #define pmd_dirty(pmd)          pte_dirty(pmd_pte(pmd))
 366 #define pmd_young(pmd)          pte_young(pmd_pte(pmd))
 367 #define pmd_wrprotect(pmd)      pte_pmd(pte_wrprotect(pmd_pte(pmd)))
 368 #define pmd_mksplitting(pmd)    pte_pmd(pte_mkspecial(pmd_pte(pmd)))
 369 #define pmd_mkold(pmd)          pte_pmd(pte_mkold(pmd_pte(pmd)))
 370 #define pmd_mkwrite(pmd)        pte_pmd(pte_mkwrite(pmd_pte(pmd)))
 371 #define pmd_mkdirty(pmd)        pte_pmd(pte_mkdirty(pmd_pte(pmd)))
 372 #define pmd_mkyoung(pmd)        pte_pmd(pte_mkyoung(pmd_pte(pmd)))
 373 #define pmd_mknotpresent(pmd)   (__pmd(pmd_val(pmd) & ~PMD_TYPE_MASK))
 374
 375 #define __HAVE_ARCH_PMD_WRITE
 376 #define pmd_write(pmd)          pte_write(pmd_pte(pmd))
 377
 378 #define pmd_mkhuge(pmd)         (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
 379
 380 #define pmd_pfn(pmd)            (((pmd_val(pmd) & PMD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
 381 #define pfn_pmd(pfn,prot)       (__pmd(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
 382 #define mk_pmd(page,prot)       pfn_pmd(page_to_pfn(page),prot)
 383
 384 #define pud_write(pud)          pte_write(pud_pte(pud))
 385 #define pud_pfn(pud)            (((pud_val(pud) & PUD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
 386
 387 #define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
 388
 389 static inline int has_transparent_hugepage(void)
 390 {
 391         return 1;
 392 }
 393
 394 #define __pgprot_modify(prot,mask,bits) \
 395         __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
 396
 397 /*
 398  * Mark the prot value as uncacheable and unbufferable.
 399  */
 400 #define pgprot_noncached(prot) \
 401         __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
 402 #define pgprot_writecombine(prot) \
 403         __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
 404 #define pgprot_device(prot) \
 405         __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
 406 #define __HAVE_PHYS_MEM_ACCESS_PROT
 407 struct file;
 408 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 409                                      unsigned long size, pgprot_t vma_prot);
 410
 411 #define pmd_none(pmd)           (!pmd_val(pmd))
 412 #define pmd_present(pmd)        (pmd_val(pmd))
 413
 414 #define pmd_bad(pmd)            (!(pmd_val(pmd) & 2))
 415
 416 #define pmd_table(pmd)          ((pmd_val(pmd) & PMD_TYPE_MASK) == \
 417                                  PMD_TYPE_TABLE)
 418 #define pmd_sect(pmd)           ((pmd_val(pmd) & PMD_TYPE_MASK) == \
 419                                  PMD_TYPE_SECT)
 420
 421 #ifdef CONFIG_ARM64_64K_PAGES
 422 #define pud_sect(pud)           (0)
 423 #define pud_table(pud)          (1)
 424 #else
 425 #define pud_sect(pud)           ((pud_val(pud) & PUD_TYPE_MASK) == \
 426                                  PUD_TYPE_SECT)
 427 #define pud_table(pud)          ((pud_val(pud) & PUD_TYPE_MASK) == \
 428                                  PUD_TYPE_TABLE)
 429 #endif
 430
 431 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
 432 {
 433         *pmdp = pmd;
 434         dsb(ishst);
 435         isb();
 436 }
 437
 438 static inline void pmd_clear(pmd_t *pmdp)
 439 {
 440         set_pmd(pmdp, __pmd(0));
 441 }
 442
 443 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
 444 {
 445         return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
 446 }
 447
 448 #define pmd_page(pmd)           pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
 449
 450 /*
 451  * Conversion functions: convert a page and protection to a page entry,
 452  * and a page entry and page directory to the page they refer to.
 453  */
 454 #define mk_pte(page,prot)       pfn_pte(page_to_pfn(page),prot)
 455
 456 #if CONFIG_PGTABLE_LEVELS > 2
 457
 458 #define pmd_ERROR(pmd)          __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
 459
 460 #define pud_none(pud)           (!pud_val(pud))
 461 #define pud_bad(pud)            (!(pud_val(pud) & 2))
 462 #define pud_present(pud)        (pud_val(pud))
 463
 464 static inline void set_pud(pud_t *pudp, pud_t pud)
 465 {
 466         *pudp = pud;
 467         dsb(ishst);
 468         isb();
 469 }
 470
 471 static inline void pud_clear(pud_t *pudp)
 472 {
 473         set_pud(pudp, __pud(0));
 474 }
 475
 476 static inline pmd_t *pud_page_vaddr(pud_t pud)
 477 {
 478         return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK);
 479 }
 480
 481 /* Find an entry in the second-level page table. */
 482 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
 483
 484 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
 485 {
 486         return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr);
 487 }
 488
 489 #define pud_page(pud)           pfn_to_page(__phys_to_pfn(pud_val(pud) & PHYS_MASK))
 490
 491 #endif  /* CONFIG_PGTABLE_LEVELS > 2 */
 492
 493 #if CONFIG_PGTABLE_LEVELS > 3
 494
 495 #define pud_ERROR(pud)          __pud_error(__FILE__, __LINE__, pud_val(pud))
 496
 497 #define pgd_none(pgd)           (!pgd_val(pgd))
 498 #define pgd_bad(pgd)            (!(pgd_val(pgd) & 2))
 499 #define pgd_present(pgd)        (pgd_val(pgd))
 500
 501 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 502 {
 503         *pgdp = pgd;
 504         dsb(ishst);
 505 }
 506
 507 static inline void pgd_clear(pgd_t *pgdp)
 508 {
 509         set_pgd(pgdp, __pgd(0));
 510 }
 511
 512 static inline pud_t *pgd_page_vaddr(pgd_t pgd)
 513 {
 514         return __va(pgd_val(pgd) & PHYS_MASK & (s32)PAGE_MASK);
 515 }
 516
 517 /* Find an entry in the frst-level page table. */
 518 #define pud_index(addr)         (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
 519
 520 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long addr)
 521 {
 522         return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(addr);
 523 }
 524
 525 #define pgd_page(pgd)           pfn_to_page(__phys_to_pfn(pgd_val(pgd) & PHYS_MASK))
 526
 527 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
 528
 529 #define pgd_ERROR(pgd)          __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
 530
 531 /* to find an entry in a page-table-directory */
 532 #define pgd_index(addr)         (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
 533
 534 #define pgd_offset(mm, addr)    ((mm)->pgd+pgd_index(addr))
 535
 536 /* to find an entry in a kernel page-table-directory */
 537 #define pgd_offset_k(addr)      pgd_offset(&init_mm, addr)
 538
 539 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 540 {
 541         const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
 542                               PTE_PROT_NONE | PTE_VALID | PTE_WRITE;
 543         /* preserve the hardware dirty information */
 544         if (pte_hw_dirty(pte))
 545                 pte = pte_mkdirty(pte);
 546         pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
 547         return pte;
 548 }
 549
 550 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
 551 {
 552         return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
 553 }
 554
 555 #ifdef CONFIG_ARM64_HW_AFDBM
 556 /*
 557  * Atomic pte/pmd modifications.
 558  */
 559 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 560 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
 561                                             unsigned long address,
 562                                             pte_t *ptep)
 563 {
 564         pteval_t pteval;
 565         unsigned int tmp, res;
 566
 567         asm volatile("//        ptep_test_and_clear_young\n"
 568         "       prfm    pstl1strm, %2\n"
 569         "1:     ldxr    %0, %2\n"
 570         "       ubfx    %w3, %w0, %5, #1        // extract PTE_AF (young)\n"
 571         "       and     %0, %0, %4              // clear PTE_AF\n"
 572         "       stxr    %w1, %0, %2\n"
 573         "       cbnz    %w1, 1b\n"
 574         : "=&r" (pteval), "=&r" (tmp), "+Q" (pte_val(*ptep)), "=&r" (res)
 575         : "L" (~PTE_AF), "I" (ilog2(PTE_AF)));
 576
 577         return res;
 578 }
 579
 580 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 581 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
 582 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 583                                             unsigned long address,
 584                                             pmd_t *pmdp)
 585 {
 586         return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
 587 }
 588 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 589
 590 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 591 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 592                                        unsigned long address, pte_t *ptep)
 593 {
 594         pteval_t old_pteval;
 595         unsigned int tmp;
 596
 597         asm volatile("//        ptep_get_and_clear\n"
 598         "       prfm    pstl1strm, %2\n"
 599         "1:     ldxr    %0, %2\n"
 600         "       stxr    %w1, xzr, %2\n"
 601         "       cbnz    %w1, 1b\n"
 602         : "=&r" (old_pteval), "=&r" (tmp), "+Q" (pte_val(*ptep)));
 603
 604         return __pte(old_pteval);
 605 }
 606
 607 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 608 #define __HAVE_ARCH_PMDP_GET_AND_CLEAR
 609 static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
 610                                        unsigned long address, pmd_t *pmdp)
 611 {
 612         return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
 613 }
 614 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 615
 616 /*
 617  * ptep_set_wrprotect - mark read-only while trasferring potential hardware
 618  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
 619  */
 620 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 621 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
 622 {
 623         pteval_t pteval;
 624         unsigned long tmp;
 625
 626         asm volatile("//        ptep_set_wrprotect\n"
 627         "       prfm    pstl1strm, %2\n"
 628         "1:     ldxr    %0, %2\n"
 629         "       tst     %0, %4                  // check for hw dirty (!PTE_RDONLY)\n"
 630         "       csel    %1, %3, xzr, eq         // set PTE_DIRTY|PTE_RDONLY if dirty\n"
 631         "       orr     %0, %0, %1              // if !dirty, PTE_RDONLY is already set\n"
 632         "       and     %0, %0, %5              // clear PTE_WRITE/PTE_DBM\n"
 633         "       stxr    %w1, %0, %2\n"
 634         "       cbnz    %w1, 1b\n"
 635         : "=&r" (pteval), "=&r" (tmp), "+Q" (pte_val(*ptep))
 636         : "r" (PTE_DIRTY|PTE_RDONLY), "L" (PTE_RDONLY), "L" (~PTE_WRITE)
 637         : "cc");
 638 }
 639
 640 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 641 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
 642 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
 643                                       unsigned long address, pmd_t *pmdp)
 644 {
 645         ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
 646 }
 647 #endif
 648 #endif  /* CONFIG_ARM64_HW_AFDBM */
 649
 650 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
 651 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
 652
 653 /*
 654  * Encode and decode a swap entry:
 655  *      bits 0-1:       present (must be zero)
 656  *      bits 2-7:       swap type
 657  *      bits 8-57:      swap offset
 658  */
 659 #define __SWP_TYPE_SHIFT        2
 660 #define __SWP_TYPE_BITS         6
 661 #define __SWP_OFFSET_BITS       50
 662 #define __SWP_TYPE_MASK         ((1 << __SWP_TYPE_BITS) - 1)
 663 #define __SWP_OFFSET_SHIFT      (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
 664 #define __SWP_OFFSET_MASK       ((1UL << __SWP_OFFSET_BITS) - 1)
 665
 666 #define __swp_type(x)           (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
 667 #define __swp_offset(x)         (((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
 668 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
 669
 670 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
 671 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
 672
 673 /*
 674  * Ensure that there are not more swap files than can be encoded in the kernel
 675  * PTEs.
 676  */
 677 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
 678
 679 extern int kern_addr_valid(unsigned long addr);
 680
 681 #include <asm-generic/pgtable.h>
 682
 683 void pgd_cache_init(void);
 684 #define pgtable_cache_init      pgd_cache_init
 685
 686 /*
 687  * On AArch64, the cache coherency is handled via the set_pte_at() function.
 688  */
 689 static inline void update_mmu_cache(struct vm_area_struct *vma,
 690                                     unsigned long addr, pte_t *ptep)
 691 {
 692         /*
 693          * We don't do anything here, so there's a very small chance of
 694          * us retaking a user fault which we just fixed up. The alternative
 695          * is doing a dsb(ishst), but that penalises the fastpath.
 696          */
 697 }
 698
 699 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
 700
 701 #define kc_vaddr_to_offset(v)   ((v) & ~VA_START)
 702 #define kc_offset_to_vaddr(o)   ((o) | VA_START)
 703
 704 #endif /* !__ASSEMBLY__ */
 705
 706 #endif /* __ASM_PGTABLE_H */