LXR linux/arch/loongarch/include/asm/pgtable.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
   4 *
   5 * Derived from MIPS:
   6 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
   7 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
   8 */
   9#ifndef _ASM_PGTABLE_H
  10#define _ASM_PGTABLE_H
  11
  12#include <linux/compiler.h>
  13#include <asm/addrspace.h>
  14#include <asm/pgtable-bits.h>
  15
  16#if CONFIG_PGTABLE_LEVELS == 2
  17#include <asm-generic/pgtable-nopmd.h>
  18#elif CONFIG_PGTABLE_LEVELS == 3
  19#include <asm-generic/pgtable-nopud.h>
  20#else
  21#include <asm-generic/pgtable-nop4d.h>
  22#endif
  23
  24#define PGD_ORDER               0
  25#define PUD_ORDER               0
  26#define PMD_ORDER               0
  27#define PTE_ORDER               0
  28
  29#if CONFIG_PGTABLE_LEVELS == 2
  30#define PGDIR_SHIFT     (PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
  31#elif CONFIG_PGTABLE_LEVELS == 3
  32#define PMD_SHIFT       (PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
  33#define PMD_SIZE        (1UL << PMD_SHIFT)
  34#define PMD_MASK        (~(PMD_SIZE-1))
  35#define PGDIR_SHIFT     (PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
  36#elif CONFIG_PGTABLE_LEVELS == 4
  37#define PMD_SHIFT       (PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
  38#define PMD_SIZE        (1UL << PMD_SHIFT)
  39#define PMD_MASK        (~(PMD_SIZE-1))
  40#define PUD_SHIFT       (PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
  41#define PUD_SIZE        (1UL << PUD_SHIFT)
  42#define PUD_MASK        (~(PUD_SIZE-1))
  43#define PGDIR_SHIFT     (PUD_SHIFT + (PAGE_SHIFT + PUD_ORDER - 3))
  44#endif
  45
  46#define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  47#define PGDIR_MASK      (~(PGDIR_SIZE-1))
  48
  49#define VA_BITS         (PGDIR_SHIFT + (PAGE_SHIFT + PGD_ORDER - 3))
  50
  51#define PTRS_PER_PGD    ((PAGE_SIZE << PGD_ORDER) >> 3)
  52#if CONFIG_PGTABLE_LEVELS > 3
  53#define PTRS_PER_PUD    ((PAGE_SIZE << PUD_ORDER) >> 3)
  54#endif
  55#if CONFIG_PGTABLE_LEVELS > 2
  56#define PTRS_PER_PMD    ((PAGE_SIZE << PMD_ORDER) >> 3)
  57#endif
  58#define PTRS_PER_PTE    ((PAGE_SIZE << PTE_ORDER) >> 3)
  59
  60#define USER_PTRS_PER_PGD       ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
  61
  62#ifndef __ASSEMBLY__
  63
  64#include <linux/mm_types.h>
  65#include <linux/mmzone.h>
  66#include <asm/fixmap.h>
  67#include <asm/io.h>
  68
  69struct mm_struct;
  70struct vm_area_struct;
  71
  72/*
  73 * ZERO_PAGE is a global shared page that is always zero; used
  74 * for zero-mapped memory areas etc..
  75 */
  76
  77extern unsigned long empty_zero_page;
  78extern unsigned long zero_page_mask;
  79
  80#define ZERO_PAGE(vaddr) \
  81        (virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
  82#define __HAVE_COLOR_ZERO_PAGE
  83
  84/*
  85 * TLB refill handlers may also map the vmalloc area into xkvrange.
  86 * Avoid the first couple of pages so NULL pointer dereferences will
  87 * still reliably trap.
  88 */
  89#define MODULES_VADDR   (vm_map_base + PCI_IOSIZE + (2 * PAGE_SIZE))
  90#define MODULES_END     (MODULES_VADDR + SZ_256M)
  91
  92#define VMALLOC_START   MODULES_END
  93#define VMALLOC_END     \
  94        (vm_map_base +  \
  95         min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, (1UL << cpu_vabits)) - PMD_SIZE)
  96
  97#define pte_ERROR(e) \
  98        pr_err("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
  99#ifndef __PAGETABLE_PMD_FOLDED
 100#define pmd_ERROR(e) \
 101        pr_err("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
 102#endif
 103#ifndef __PAGETABLE_PUD_FOLDED
 104#define pud_ERROR(e) \
 105        pr_err("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
 106#endif
 107#define pgd_ERROR(e) \
 108        pr_err("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
 109
 110extern pte_t invalid_pte_table[PTRS_PER_PTE];
 111
 112#ifndef __PAGETABLE_PUD_FOLDED
 113
 114typedef struct { unsigned long pud; } pud_t;
 115#define pud_val(x)      ((x).pud)
 116#define __pud(x)        ((pud_t) { (x) })
 117
 118extern pud_t invalid_pud_table[PTRS_PER_PUD];
 119
 120/*
 121 * Empty pgd/p4d entries point to the invalid_pud_table.
 122 */
 123static inline int p4d_none(p4d_t p4d)
 124{
 125        return p4d_val(p4d) == (unsigned long)invalid_pud_table;
 126}
 127
 128static inline int p4d_bad(p4d_t p4d)
 129{
 130        return p4d_val(p4d) & ~PAGE_MASK;
 131}
 132
 133static inline int p4d_present(p4d_t p4d)
 134{
 135        return p4d_val(p4d) != (unsigned long)invalid_pud_table;
 136}
 137
 138static inline void p4d_clear(p4d_t *p4dp)
 139{
 140        p4d_val(*p4dp) = (unsigned long)invalid_pud_table;
 141}
 142
 143static inline pud_t *p4d_pgtable(p4d_t p4d)
 144{
 145        return (pud_t *)p4d_val(p4d);
 146}
 147
 148static inline void set_p4d(p4d_t *p4d, p4d_t p4dval)
 149{
 150        *p4d = p4dval;
 151}
 152
 153#define p4d_phys(p4d)           virt_to_phys((void *)p4d_val(p4d))
 154#define p4d_page(p4d)           (pfn_to_page(p4d_phys(p4d) >> PAGE_SHIFT))
 155
 156#endif
 157
 158#ifndef __PAGETABLE_PMD_FOLDED
 159
 160typedef struct { unsigned long pmd; } pmd_t;
 161#define pmd_val(x)      ((x).pmd)
 162#define __pmd(x)        ((pmd_t) { (x) })
 163
 164extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
 165
 166/*
 167 * Empty pud entries point to the invalid_pmd_table.
 168 */
 169static inline int pud_none(pud_t pud)
 170{
 171        return pud_val(pud) == (unsigned long)invalid_pmd_table;
 172}
 173
 174static inline int pud_bad(pud_t pud)
 175{
 176        return pud_val(pud) & ~PAGE_MASK;
 177}
 178
 179static inline int pud_present(pud_t pud)
 180{
 181        return pud_val(pud) != (unsigned long)invalid_pmd_table;
 182}
 183
 184static inline void pud_clear(pud_t *pudp)
 185{
 186        pud_val(*pudp) = ((unsigned long)invalid_pmd_table);
 187}
 188
 189static inline pmd_t *pud_pgtable(pud_t pud)
 190{
 191        return (pmd_t *)pud_val(pud);
 192}
 193
 194#define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while (0)
 195
 196#define pud_phys(pud)           virt_to_phys((void *)pud_val(pud))
 197#define pud_page(pud)           (pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
 198
 199#endif
 200
 201/*
 202 * Empty pmd entries point to the invalid_pte_table.
 203 */
 204static inline int pmd_none(pmd_t pmd)
 205{
 206        return pmd_val(pmd) == (unsigned long)invalid_pte_table;
 207}
 208
 209static inline int pmd_bad(pmd_t pmd)
 210{
 211        return (pmd_val(pmd) & ~PAGE_MASK);
 212}
 213
 214static inline int pmd_present(pmd_t pmd)
 215{
 216        if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
 217                return !!(pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROTNONE));
 218
 219        return pmd_val(pmd) != (unsigned long)invalid_pte_table;
 220}
 221
 222static inline void pmd_clear(pmd_t *pmdp)
 223{
 224        pmd_val(*pmdp) = ((unsigned long)invalid_pte_table);
 225}
 226
 227#define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while (0)
 228
 229#define pmd_phys(pmd)           virt_to_phys((void *)pmd_val(pmd))
 230
 231#ifndef CONFIG_TRANSPARENT_HUGEPAGE
 232#define pmd_page(pmd)           (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
 233#endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
 234
 235#define pmd_page_vaddr(pmd)     pmd_val(pmd)
 236
 237extern pmd_t mk_pmd(struct page *page, pgprot_t prot);
 238extern void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd);
 239
 240#define pte_page(x)             pfn_to_page(pte_pfn(x))
 241#define pte_pfn(x)              ((unsigned long)(((x).pte & _PFN_MASK) >> _PFN_SHIFT))
 242#define pfn_pte(pfn, prot)      __pte(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
 243#define pfn_pmd(pfn, prot)      __pmd(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
 244
 245/*
 246 * Initialize a new pgd / pmd table with invalid pointers.
 247 */
 248extern void pgd_init(unsigned long page);
 249extern void pud_init(unsigned long page, unsigned long pagetable);
 250extern void pmd_init(unsigned long page, unsigned long pagetable);
 251
 252/*
 253 * Non-present pages:  high 40 bits are offset, next 8 bits type,
 254 * low 16 bits zero.
 255 */
 256static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
 257{ pte_t pte; pte_val(pte) = (type << 16) | (offset << 24); return pte; }
 258
 259#define __swp_type(x)           (((x).val >> 16) & 0xff)
 260#define __swp_offset(x)         ((x).val >> 24)
 261#define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
 262#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
 263#define __swp_entry_to_pte(x)   ((pte_t) { (x).val })
 264#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
 265#define __swp_entry_to_pmd(x)   ((pmd_t) { (x).val | _PAGE_HUGE })
 266
 267extern void paging_init(void);
 268
 269#define pte_none(pte)           (!(pte_val(pte) & ~_PAGE_GLOBAL))
 270#define pte_present(pte)        (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROTNONE))
 271#define pte_no_exec(pte)        (pte_val(pte) & _PAGE_NO_EXEC)
 272
 273static inline void set_pte(pte_t *ptep, pte_t pteval)
 274{
 275        *ptep = pteval;
 276        if (pte_val(pteval) & _PAGE_GLOBAL) {
 277                pte_t *buddy = ptep_buddy(ptep);
 278                /*
 279                 * Make sure the buddy is global too (if it's !none,
 280                 * it better already be global)
 281                 */
 282#ifdef CONFIG_SMP
 283                /*
 284                 * For SMP, multiple CPUs can race, so we need to do
 285                 * this atomically.
 286                 */
 287                unsigned long page_global = _PAGE_GLOBAL;
 288                unsigned long tmp;
 289
 290                __asm__ __volatile__ (
 291                "1:"    __LL    "%[tmp], %[buddy]               \n"
 292                "       bnez    %[tmp], 2f                      \n"
 293                "        or     %[tmp], %[tmp], %[global]       \n"
 294                        __SC    "%[tmp], %[buddy]               \n"
 295                "       beqz    %[tmp], 1b                      \n"
 296                "       nop                                     \n"
 297                "2:                                             \n"
 298                __WEAK_LLSC_MB
 299                : [buddy] "+m" (buddy->pte), [tmp] "=&r" (tmp)
 300                : [global] "r" (page_global));
 301#else /* !CONFIG_SMP */
 302                if (pte_none(*buddy))
 303                        pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL;
 304#endif /* CONFIG_SMP */
 305        }
 306}
 307
 308static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 309                              pte_t *ptep, pte_t pteval)
 310{
 311        set_pte(ptep, pteval);
 312}
 313
 314static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 315{
 316        /* Preserve global status for the pair */
 317        if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
 318                set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
 319        else
 320                set_pte_at(mm, addr, ptep, __pte(0));
 321}
 322
 323#define PGD_T_LOG2      (__builtin_ffs(sizeof(pgd_t)) - 1)
 324#define PMD_T_LOG2      (__builtin_ffs(sizeof(pmd_t)) - 1)
 325#define PTE_T_LOG2      (__builtin_ffs(sizeof(pte_t)) - 1)
 326
 327extern pgd_t swapper_pg_dir[];
 328extern pgd_t invalid_pg_dir[];
 329
 330/*
 331 * The following only work if pte_present() is true.
 332 * Undefined behaviour if not..
 333 */
 334static inline int pte_write(pte_t pte)  { return pte_val(pte) & _PAGE_WRITE; }
 335static inline int pte_young(pte_t pte)  { return pte_val(pte) & _PAGE_ACCESSED; }
 336static inline int pte_dirty(pte_t pte)  { return pte_val(pte) & _PAGE_MODIFIED; }
 337
 338static inline pte_t pte_mkold(pte_t pte)
 339{
 340        pte_val(pte) &= ~_PAGE_ACCESSED;
 341        return pte;
 342}
 343
 344static inline pte_t pte_mkyoung(pte_t pte)
 345{
 346        pte_val(pte) |= _PAGE_ACCESSED;
 347        return pte;
 348}
 349
 350static inline pte_t pte_mkclean(pte_t pte)
 351{
 352        pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_MODIFIED);
 353        return pte;
 354}
 355
 356static inline pte_t pte_mkdirty(pte_t pte)
 357{
 358        pte_val(pte) |= (_PAGE_DIRTY | _PAGE_MODIFIED);
 359        return pte;
 360}
 361
 362static inline pte_t pte_mkwrite(pte_t pte)
 363{
 364        pte_val(pte) |= (_PAGE_WRITE | _PAGE_DIRTY);
 365        return pte;
 366}
 367
 368static inline pte_t pte_wrprotect(pte_t pte)
 369{
 370        pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_DIRTY);
 371        return pte;
 372}
 373
 374static inline int pte_huge(pte_t pte)   { return pte_val(pte) & _PAGE_HUGE; }
 375
 376static inline pte_t pte_mkhuge(pte_t pte)
 377{
 378        pte_val(pte) |= _PAGE_HUGE;
 379        return pte;
 380}
 381
 382#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
 383static inline int pte_special(pte_t pte)        { return pte_val(pte) & _PAGE_SPECIAL; }
 384static inline pte_t pte_mkspecial(pte_t pte)    { pte_val(pte) |= _PAGE_SPECIAL; return pte; }
 385#endif /* CONFIG_ARCH_HAS_PTE_SPECIAL */
 386
 387#define pte_accessible pte_accessible
 388static inline unsigned long pte_accessible(struct mm_struct *mm, pte_t a)
 389{
 390        if (pte_val(a) & _PAGE_PRESENT)
 391                return true;
 392
 393        if ((pte_val(a) & _PAGE_PROTNONE) &&
 394                        atomic_read(&mm->tlb_flush_pending))
 395                return true;
 396
 397        return false;
 398}
 399
 400/*
 401 * Conversion functions: convert a page and protection to a page entry,
 402 * and a page entry and page directory to the page they refer to.
 403 */
 404#define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
 405
 406static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 407{
 408        return __pte((pte_val(pte) & _PAGE_CHG_MASK) |
 409                     (pgprot_val(newprot) & ~_PAGE_CHG_MASK));
 410}
 411
 412extern void __update_tlb(struct vm_area_struct *vma,
 413                        unsigned long address, pte_t *ptep);
 414
 415static inline void update_mmu_cache(struct vm_area_struct *vma,
 416                        unsigned long address, pte_t *ptep)
 417{
 418        __update_tlb(vma, address, ptep);
 419}
 420
 421static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
 422                        unsigned long address, pmd_t *pmdp)
 423{
 424        __update_tlb(vma, address, (pte_t *)pmdp);
 425}
 426
 427#define kern_addr_valid(addr)   (1)
 428
 429static inline unsigned long pmd_pfn(pmd_t pmd)
 430{
 431        return (pmd_val(pmd) & _PFN_MASK) >> _PFN_SHIFT;
 432}
 433
 434#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 435
 436/* We don't have hardware dirty/accessed bits, generic_pmdp_establish is fine.*/
 437#define pmdp_establish generic_pmdp_establish
 438
 439static inline int pmd_trans_huge(pmd_t pmd)
 440{
 441        return !!(pmd_val(pmd) & _PAGE_HUGE) && pmd_present(pmd);
 442}
 443
 444static inline pmd_t pmd_mkhuge(pmd_t pmd)
 445{
 446        pmd_val(pmd) = (pmd_val(pmd) & ~(_PAGE_GLOBAL)) |
 447                ((pmd_val(pmd) & _PAGE_GLOBAL) << (_PAGE_HGLOBAL_SHIFT - _PAGE_GLOBAL_SHIFT));
 448        pmd_val(pmd) |= _PAGE_HUGE;
 449
 450        return pmd;
 451}
 452
 453#define pmd_write pmd_write
 454static inline int pmd_write(pmd_t pmd)
 455{
 456        return !!(pmd_val(pmd) & _PAGE_WRITE);
 457}
 458
 459static inline pmd_t pmd_mkwrite(pmd_t pmd)
 460{
 461        pmd_val(pmd) |= (_PAGE_WRITE | _PAGE_DIRTY);
 462        return pmd;
 463}
 464
 465static inline pmd_t pmd_wrprotect(pmd_t pmd)
 466{
 467        pmd_val(pmd) &= ~(_PAGE_WRITE | _PAGE_DIRTY);
 468        return pmd;
 469}
 470
 471static inline int pmd_dirty(pmd_t pmd)
 472{
 473        return !!(pmd_val(pmd) & _PAGE_MODIFIED);
 474}
 475
 476static inline pmd_t pmd_mkclean(pmd_t pmd)
 477{
 478        pmd_val(pmd) &= ~(_PAGE_DIRTY | _PAGE_MODIFIED);
 479        return pmd;
 480}
 481
 482static inline pmd_t pmd_mkdirty(pmd_t pmd)
 483{
 484        pmd_val(pmd) |= (_PAGE_DIRTY | _PAGE_MODIFIED);
 485        return pmd;
 486}
 487
 488static inline int pmd_young(pmd_t pmd)
 489{
 490        return !!(pmd_val(pmd) & _PAGE_ACCESSED);
 491}
 492
 493static inline pmd_t pmd_mkold(pmd_t pmd)
 494{
 495        pmd_val(pmd) &= ~_PAGE_ACCESSED;
 496        return pmd;
 497}
 498
 499static inline pmd_t pmd_mkyoung(pmd_t pmd)
 500{
 501        pmd_val(pmd) |= _PAGE_ACCESSED;
 502        return pmd;
 503}
 504
 505static inline struct page *pmd_page(pmd_t pmd)
 506{
 507        if (pmd_trans_huge(pmd))
 508                return pfn_to_page(pmd_pfn(pmd));
 509
 510        return pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT);
 511}
 512
 513static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
 514{
 515        pmd_val(pmd) = (pmd_val(pmd) & _HPAGE_CHG_MASK) |
 516                                (pgprot_val(newprot) & ~_HPAGE_CHG_MASK);
 517        return pmd;
 518}
 519
 520static inline pmd_t pmd_mkinvalid(pmd_t pmd)
 521{
 522        pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY | _PAGE_PROTNONE);
 523
 524        return pmd;
 525}
 526
 527/*
 528 * The generic version pmdp_huge_get_and_clear uses a version of pmd_clear() with a
 529 * different prototype.
 530 */
 531#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
 532static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
 533                                            unsigned long address, pmd_t *pmdp)
 534{
 535        pmd_t old = *pmdp;
 536
 537        pmd_clear(pmdp);
 538
 539        return old;
 540}
 541
 542#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 543
 544#ifdef CONFIG_NUMA_BALANCING
 545static inline long pte_protnone(pte_t pte)
 546{
 547        return (pte_val(pte) & _PAGE_PROTNONE);
 548}
 549
 550static inline long pmd_protnone(pmd_t pmd)
 551{
 552        return (pmd_val(pmd) & _PAGE_PROTNONE);
 553}
 554#endif /* CONFIG_NUMA_BALANCING */
 555
 556/*
 557 * We provide our own get_unmapped area to cope with the virtual aliasing
 558 * constraints placed on us by the cache architecture.
 559 */
 560#define HAVE_ARCH_UNMAPPED_AREA
 561#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
 562
 563#endif /* !__ASSEMBLY__ */
 564
 565#endif /* _ASM_PGTABLE_H */
 566