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 #define arch_clear_hugepage_flags(page)         do { } while (0)
  41
  42 static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
  43                                   pte_t *ptep, unsigned long sz)
  44 {
  45         if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
  46                 pte_val(*ptep) = _REGION3_ENTRY_EMPTY;
  47         else
  48                 pte_val(*ptep) = _SEGMENT_ENTRY_EMPTY;
  49 }
  50
  51 static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
  52                                          unsigned long address, pte_t *ptep)
  53 {
  54         huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
  55 }
  56
  57 static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
  58                                              unsigned long addr, pte_t *ptep,
  59                                              pte_t pte, int dirty)
  60 {
  61         int changed = !pte_same(huge_ptep_get(ptep), pte);
  62         if (changed) {
  63                 huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
  64                 set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
  65         }
  66         return changed;
  67 }
  68
  69 static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
  70                                            unsigned long addr, pte_t *ptep)
  71 {
  72         pte_t pte = huge_ptep_get_and_clear(mm, addr, ptep);
  73         set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte));
  74 }
  75
  76 static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
  77 {
  78         return mk_pte(page, pgprot);
  79 }
  80
  81 static inline int huge_pte_none(pte_t pte)
  82 {
  83         return pte_none(pte);
  84 }
  85
  86 static inline int huge_pte_write(pte_t pte)
  87 {
  88         return pte_write(pte);
  89 }
  90
  91 static inline int huge_pte_dirty(pte_t pte)
  92 {
  93         return pte_dirty(pte);
  94 }
  95
  96 static inline pte_t huge_pte_mkwrite(pte_t pte)
  97 {
  98         return pte_mkwrite(pte);
  99 }
 100
 101 static inline pte_t huge_pte_mkdirty(pte_t pte)
 102 {
 103         return pte_mkdirty(pte);
 104 }
 105
 106 static inline pte_t huge_pte_wrprotect(pte_t pte)
 107 {
 108         return pte_wrprotect(pte);
 109 }
 110
 111 static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
 112 {
 113         return pte_modify(pte, newprot);
 114 }
 115
 116 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
 117 static inline bool gigantic_page_supported(void) { return true; }
 118 #endif
 119 #endif /* _ASM_S390_HUGETLB_H */