linux/arch/s390/include/asm/hugetlb.h
Dominik Dingel 7f9be77555 s390/hugetlb: add hugepages_supported define
On s390 we only can enable hugepages if the underlying hardware/hypervisor
also does support this.  Common code now would assume this to be
signaled by setting HPAGE_SHIFT to 0.  But on s390, where we only
support one hugepage size, there is a link between HPAGE_SHIFT and
pageblock_order.

So instead of setting HPAGE_SHIFT to 0, we will implement the check for
the hardware capability.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:52 -07:00

113 lines
2.5 KiB
C

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