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