arch/tile/include/asm/pgtable_64.h

   1 /*
   2  * Copyright 2011 Tilera Corporation. All Rights Reserved.
   3  *
   4  *   This program is free software; you can redistribute it and/or
   5  *   modify it under the terms of the GNU General Public License
   6  *   as published by the Free Software Foundation, version 2.
   7  *
   8  *   This program is distributed in the hope that it will be useful, but
   9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11  *   NON INFRINGEMENT.  See the GNU General Public License for
  12  *   more details.
  13  *
  14  */
  15
  16 #ifndef _ASM_TILE_PGTABLE_64_H
  17 #define _ASM_TILE_PGTABLE_64_H
  18
  19 /* The level-0 page table breaks the address space into 32-bit chunks. */
  20 #define PGDIR_SHIFT     HV_LOG2_L1_SPAN
  21 #define PGDIR_SIZE      HV_L1_SPAN
  22 #define PGDIR_MASK      (~(PGDIR_SIZE-1))
  23 #define PTRS_PER_PGD    HV_L0_ENTRIES
  24 #define PGD_INDEX(va)   HV_L0_INDEX(va)
  25 #define SIZEOF_PGD      HV_L0_SIZE
  26
  27 /*
  28  * The level-1 index is defined by the huge page size.  A PMD is composed
  29  * of PTRS_PER_PMD pgd_t's and is the middle level of the page table.
  30  */
  31 #define PMD_SHIFT       HPAGE_SHIFT
  32 #define PMD_SIZE        HPAGE_SIZE
  33 #define PMD_MASK        (~(PMD_SIZE-1))
  34 #define PTRS_PER_PMD    _HV_L1_ENTRIES(HPAGE_SHIFT)
  35 #define PMD_INDEX(va)   _HV_L1_INDEX(va, HPAGE_SHIFT)
  36 #define SIZEOF_PMD      _HV_L1_SIZE(HPAGE_SHIFT)
  37
  38 /*
  39  * The level-2 index is defined by the difference between the huge
  40  * page size and the normal page size.  A PTE is composed of
  41  * PTRS_PER_PTE pte_t's and is the bottom level of the page table.
  42  * Note that the hypervisor docs use PTE for what we call pte_t, so
  43  * this nomenclature is somewhat confusing.
  44  */
  45 #define PTRS_PER_PTE    _HV_L2_ENTRIES(HPAGE_SHIFT, PAGE_SHIFT)
  46 #define PTE_INDEX(va)   _HV_L2_INDEX(va, HPAGE_SHIFT, PAGE_SHIFT)
  47 #define SIZEOF_PTE      _HV_L2_SIZE(HPAGE_SHIFT, PAGE_SHIFT)
  48
  49 /*
  50  * Align the vmalloc area to an L2 page table.  Omit guard pages at
  51  * the beginning and end for simplicity (particularly in the per-cpu
  52  * memory allocation code).  The vmalloc code puts in an internal
  53  * guard page between each allocation.
  54  */
  55 #define _VMALLOC_END    HUGE_VMAP_BASE
  56 #define VMALLOC_END     _VMALLOC_END
  57 #define VMALLOC_START   _VMALLOC_START
  58
  59 #define HUGE_VMAP_END   (HUGE_VMAP_BASE + PGDIR_SIZE)
  60
  61 #ifndef __ASSEMBLY__
  62
  63 /* We have no pud since we are a three-level page table. */
  64 #include <asm-generic/pgtable-nopud.h>
  65
  66 /*
  67  * pmds are the same as pgds and ptes, so converting is a no-op.
  68  */
  69 #define pmd_pte(pmd) (pmd)
  70 #define pmdp_ptep(pmdp) (pmdp)
  71 #define pte_pmd(pte) (pte)
  72
  73 #define pud_pte(pud) ((pud).pgd)
  74
  75 static inline int pud_none(pud_t pud)
  76 {
  77         return pud_val(pud) == 0;
  78 }
  79
  80 static inline int pud_present(pud_t pud)
  81 {
  82         return pud_val(pud) & _PAGE_PRESENT;
  83 }
  84
  85 static inline int pud_huge_page(pud_t pud)
  86 {
  87         return pud_val(pud) & _PAGE_HUGE_PAGE;
  88 }
  89
  90 #define pmd_ERROR(e) \
  91         pr_err("%s:%d: bad pmd 0x%016llx.\n", __FILE__, __LINE__, pmd_val(e))
  92
  93 static inline void pud_clear(pud_t *pudp)
  94 {
  95         __pte_clear(&pudp->pgd);
  96 }
  97
  98 static inline int pud_bad(pud_t pud)
  99 {
 100         return ((pud_val(pud) & _PAGE_ALL) != _PAGE_TABLE);
 101 }
 102
 103 /* Return the page-table frame number (ptfn) that a pud_t points at. */
 104 #define pud_ptfn(pud) hv_pte_get_ptfn((pud).pgd)
 105
 106 /* Return the page frame number (pfn) that a pud_t points at. */
 107 #define pud_pfn(pud) pte_pfn(pud_pte(pud))
 108
 109 /*
 110  * A given kernel pud_t maps to a kernel pmd_t table at a specific
 111  * virtual address.  Since kernel pmd_t tables can be aligned at
 112  * sub-page granularity, this macro can return non-page-aligned
 113  * pointers, despite its name.
 114  */
 115 #define pud_page_vaddr(pud) \
 116         (__va((phys_addr_t)pud_ptfn(pud) << HV_LOG2_PAGE_TABLE_ALIGN))
 117
 118 /*
 119  * A pud_t points to a pmd_t array.  Since we can have multiple per
 120  * page, we don't have a one-to-one mapping of pud_t's to pages.
 121  */
 122 #define pud_page(pud) pfn_to_page(PFN_DOWN(HV_PTFN_TO_CPA(pud_ptfn(pud))))
 123
 124 static inline unsigned long pud_index(unsigned long address)
 125 {
 126         return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1);
 127 }
 128
 129 #define pmd_offset(pud, address) \
 130         ((pmd_t *)pud_page_vaddr(*(pud)) + pmd_index(address))
 131
 132 /* Normalize an address to having the correct high bits set. */
 133 #define pgd_addr_normalize pgd_addr_normalize
 134 static inline unsigned long pgd_addr_normalize(unsigned long addr)
 135 {
 136         return ((long)addr << (CHIP_WORD_SIZE() - CHIP_VA_WIDTH())) >>
 137                 (CHIP_WORD_SIZE() - CHIP_VA_WIDTH());
 138 }
 139
 140 /* We don't define any pgds for these addresses. */
 141 static inline int pgd_addr_invalid(unsigned long addr)
 142 {
 143         return addr >= KERNEL_HIGH_VADDR || addr != pgd_addr_normalize(addr);
 144 }
 145
 146 /*
 147  * Use atomic instructions to provide atomicity against the hypervisor.
 148  */
 149 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 150 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
 151                                             unsigned long addr, pte_t *ptep)
 152 {
 153         return (__insn_fetchand(&ptep->val, ~HV_PTE_ACCESSED) >>
 154                 HV_PTE_INDEX_ACCESSED) & 0x1;
 155 }
 156
 157 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 158 static inline void ptep_set_wrprotect(struct mm_struct *mm,
 159                                       unsigned long addr, pte_t *ptep)
 160 {
 161         __insn_fetchand(&ptep->val, ~HV_PTE_WRITABLE);
 162 }
 163
 164 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 165 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 166                                        unsigned long addr, pte_t *ptep)
 167 {
 168         return hv_pte(__insn_exch(&ptep->val, 0UL));
 169 }
 170
 171 #endif /* __ASSEMBLY__ */
 172
 173 #endif /* _ASM_TILE_PGTABLE_64_H */