/* * IBM System z Huge TLB Page Support for Kernel. * * Copyright IBM Corp. 2008 * Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com> */ #ifndef _ASM_S390_HUGETLB_H #define _ASM_S390_HUGETLB_H #include <asm/page.h> #include <asm/pgtable.h> #define is_hugepage_only_range(mm, addr, len) 0 #define hugetlb_free_pgd_range free_pgd_range void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte); /* * If the arch doesn't supply something else, assume that hugepage * size aligned regions are ok without further preparation. */ static inline int prepare_hugepage_range(struct file *file, unsigned long addr, unsigned long len) { if (len & ~HPAGE_MASK) return -EINVAL; if (addr & ~HPAGE_MASK) return -EINVAL; return 0; } #define hugetlb_prefault_arch_hook(mm) do { } while (0) int arch_prepare_hugepage(struct page *page); void arch_release_hugepage(struct page *page); static inline pte_t pte_mkhuge(pte_t pte) { /* * PROT_NONE needs to be remapped from the pte type to the ste type. * The HW invalid bit is also different for pte and ste. The pte * invalid bit happens to be the same as the ste _SEGMENT_ENTRY_LARGE * bit, so we don't have to clear it. */ if (pte_val(pte) & _PAGE_INVALID) { if (pte_val(pte) & _PAGE_SWT) pte_val(pte) |= _HPAGE_TYPE_NONE; pte_val(pte) |= _SEGMENT_ENTRY_INV; } /* * Clear SW pte bits SWT and SWX, there are no SW bits in a segment * table entry. */ pte_val(pte) &= ~(_PAGE_SWT | _PAGE_SWX); /* * Also set the change-override bit because we don't need dirty bit * tracking for hugetlbfs pages. */ pte_val(pte) |= (_SEGMENT_ENTRY_LARGE | _SEGMENT_ENTRY_CO); return pte; } static inline pte_t huge_pte_wrprotect(pte_t pte) { pte_val(pte) |= _PAGE_RO; return pte; } static inline int huge_pte_none(pte_t pte) { return (pte_val(pte) & _SEGMENT_ENTRY_INV) && !(pte_val(pte) & _SEGMENT_ENTRY_RO); } static inline pte_t huge_ptep_get(pte_t *ptep) { pte_t pte = *ptep; unsigned long mask; if (!MACHINE_HAS_HPAGE) { ptep = (pte_t *) (pte_val(pte) & _SEGMENT_ENTRY_ORIGIN); if (ptep) { mask = pte_val(pte) & (_SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO); pte = pte_mkhuge(*ptep); pte_val(pte) |= mask; } } return pte; } static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { pte_t pte = huge_ptep_get(ptep); pmd_clear((pmd_t *) ptep); return pte; } static inline void __pmd_csp(pmd_t *pmdp) { register unsigned long reg2 asm("2") = pmd_val(*pmdp); register unsigned long reg3 asm("3") = pmd_val(*pmdp) | _SEGMENT_ENTRY_INV; register unsigned long reg4 asm("4") = ((unsigned long) pmdp) + 5; asm volatile( " csp %1,%3" : "=m" (*pmdp) : "d" (reg2), "d" (reg3), "d" (reg4), "m" (*pmdp) : "cc"); pmd_val(*pmdp) = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY; } static inline void __pmd_idte(unsigned long address, pmd_t *pmdp) { unsigned long sto = (unsigned long) pmdp - pmd_index(address) * sizeof(pmd_t); if (!(pmd_val(*pmdp) & _SEGMENT_ENTRY_INV)) { asm volatile( " .insn rrf,0xb98e0000,%2,%3,0,0" : "=m" (*pmdp) : "m" (*pmdp), "a" (sto), "a" ((address & HPAGE_MASK)) ); } pmd_val(*pmdp) = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY; } static inline void huge_ptep_invalidate(struct mm_struct *mm, unsigned long address, pte_t *ptep) { pmd_t *pmdp = (pmd_t *) ptep; if (!MACHINE_HAS_IDTE) { __pmd_csp(pmdp); if (mm->context.noexec) { pmdp = get_shadow_table(pmdp); __pmd_csp(pmdp); } return; } __pmd_idte(address, pmdp); if (mm->context.noexec) { pmdp = get_shadow_table(pmdp); __pmd_idte(address, pmdp); } return; } #define huge_ptep_set_access_flags(__vma, __addr, __ptep, __entry, __dirty) \ ({ \ int __changed = !pte_same(huge_ptep_get(__ptep), __entry); \ if (__changed) { \ huge_ptep_invalidate((__vma)->vm_mm, __addr, __ptep); \ set_huge_pte_at((__vma)->vm_mm, __addr, __ptep, __entry); \ } \ __changed; \ }) #define huge_ptep_set_wrprotect(__mm, __addr, __ptep) \ ({ \ pte_t __pte = huge_ptep_get(__ptep); \ if (pte_write(__pte)) { \ if (atomic_read(&(__mm)->mm_users) > 1 || \ (__mm) != current->active_mm) \ huge_ptep_invalidate(__mm, __addr, __ptep); \ set_huge_pte_at(__mm, __addr, __ptep, \ huge_pte_wrprotect(__pte)); \ } \ }) static inline void huge_ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) { huge_ptep_invalidate(vma->vm_mm, address, ptep); } #endif /* _ASM_S390_HUGETLB_H */