arch/s390/include/asm/hugetlb.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  *  IBM System z Huge TLB Page Support for Kernel.
   4  *
   5  *    Copyright IBM Corp. 2008
   6  *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
   7  */
   8
   9 #ifndef _ASM_S390_HUGETLB_H
  10 #define _ASM_S390_HUGETLB_H
  11
  12 #include <asm/page.h>
  13 #include <asm/pgtable.h>
  14
  15
  16 #define is_hugepage_only_range(mm, addr, len)   0
  17 #define hugetlb_free_pgd_range                  free_pgd_range
  18 #define hugepages_supported()                   (MACHINE_HAS_EDAT1)
  19
  20 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
  21                      pte_t *ptep, pte_t pte);
  22 pte_t huge_ptep_get(pte_t *ptep);
  23 pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
  24                               unsigned long addr, pte_t *ptep);
  25
  26 /*
  27  * If the arch doesn't supply something else, assume that hugepage
  28  * size aligned regions are ok without further preparation.
  29  */
  30 static inline int prepare_hugepage_range(struct file *file,
  31                         unsigned long addr, unsigned long len)
  32 {
  33         if (len & ~HPAGE_MASK)
  34                 return -EINVAL;
  35         if (addr & ~HPAGE_MASK)
  36                 return -EINVAL;
  37         return 0;
  38 }
  39
  40 static inline void arch_clear_hugepage_flags(struct page *page)
  41 {
  42         clear_bit(PG_arch_1, &page->flags);
  43 }
  44
  45 static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
  46                                   pte_t *ptep, unsigned long sz)
  47 {
  48         if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
  49                 pte_val(*ptep) = _REGION3_ENTRY_EMPTY;
  50         else
  51                 pte_val(*ptep) = _SEGMENT_ENTRY_EMPTY;
  52 }
  53
  54 static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
  55                                          unsigned long address, pte_t *ptep)
  56 {
  57         huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
  58 }
  59
  60 static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
  61                                              unsigned long addr, pte_t *ptep,
  62                                              pte_t pte, int dirty)
  63 {
  64         int changed = !pte_same(huge_ptep_get(ptep), pte);
  65         if (changed) {
  66                 huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
  67                 set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
  68         }
  69         return changed;
  70 }
  71
  72 static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
  73                                            unsigned long addr, pte_t *ptep)
  74 {
  75         pte_t pte = huge_ptep_get_and_clear(mm, addr, ptep);
  76         set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte));
  77 }
  78
  79 static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
  80 {
  81         return mk_pte(page, pgprot);
  82 }
  83
  84 static inline int huge_pte_none(pte_t pte)
  85 {
  86         return pte_none(pte);
  87 }
  88
  89 static inline int huge_pte_write(pte_t pte)
  90 {
  91         return pte_write(pte);
  92 }
  93
  94 static inline int huge_pte_dirty(pte_t pte)
  95 {
  96         return pte_dirty(pte);
  97 }
  98
  99 static inline pte_t huge_pte_mkwrite(pte_t pte)
 100 {
 101         return pte_mkwrite(pte);
 102 }
 103
 104 static inline pte_t huge_pte_mkdirty(pte_t pte)
 105 {
 106         return pte_mkdirty(pte);
 107 }
 108
 109 static inline pte_t huge_pte_wrprotect(pte_t pte)
 110 {
 111         return pte_wrprotect(pte);
 112 }
 113
 114 static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
 115 {
 116         return pte_modify(pte, newprot);
 117 }
 118
 119 static inline bool gigantic_page_runtime_supported(void)
 120 {
 121         return true;
 122 }
 123
 124 #endif /* _ASM_S390_HUGETLB_H */