/*
* IBM System z Huge TLB Page Support for Kernel.
*
* Copyright IBM Corp. 2008
* Author(s): Gerald Schaefer <[email protected]>
*/

#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);
pte_t huge_ptep_get(pte_t *ptep);
pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep);

/*
* 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)
#define arch_clear_hugepage_flags(page) do { } while (0)

int arch_prepare_hugepage(struct page *page);
void arch_release_hugepage(struct page *page);

static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
pte_val(*ptep) = _SEGMENT_ENTRY_EMPTY;
}

static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep)
{
huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
}

static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep,
pte_t pte, int dirty)
{
int changed = !pte_same(huge_ptep_get(ptep), pte);
if (changed) {
huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
}
return changed;
}

static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
pte_t pte = huge_ptep_get_and_clear(mm, addr, ptep);
set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte));
}

static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
{
return mk_pte(page, pgprot);
}

static inline int huge_pte_none(pte_t pte)
{
return pte_none(pte);
}

static inline int huge_pte_write(pte_t pte)
{
return pte_write(pte);
}

static inline int huge_pte_dirty(pte_t pte)
{
return pte_dirty(pte);
}

static inline pte_t huge_pte_mkwrite(pte_t pte)
{
return pte_mkwrite(pte);
}

static inline pte_t huge_pte_mkdirty(pte_t pte)
{
return pte_mkdirty(pte);
}

static inline pte_t huge_pte_wrprotect(pte_t pte)
{
return pte_wrprotect(pte);
}

static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
{
return pte_modify(pte, newprot);
}

#endif /* _ASM_S390_HUGETLB_H */