linux_dsm_epyc7002/arch/arm64/include/asm/hugetlb.h
David Woods 66b3923a1a arm64: hugetlb: add support for PTE contiguous bit
The arm64 MMU supports a Contiguous bit which is a hint that the TTE
is one of a set of contiguous entries which can be cached in a single
TLB entry.  Supporting this bit adds new intermediate huge page sizes.

The set of huge page sizes available depends on the base page size.
Without using contiguous pages the huge page sizes are as follows.

 4KB:   2MB  1GB
64KB: 512MB

With a 4KB granule, the contiguous bit groups together sets of 16 pages
and with a 64KB granule it groups sets of 32 pages.  This enables two new
huge page sizes in each case, so that the full set of available sizes
is as follows.

 4KB:  64KB   2MB  32MB  1GB
64KB:   2MB 512MB  16GB

If a 16KB granule is used then the contiguous bit groups 128 pages
at the PTE level and 32 pages at the PMD level.

If the base page size is set to 64KB then 2MB pages are enabled by
default.  It is possible in the future to make 2MB the default huge
page size for both 4KB and 64KB granules.

Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Reviewed-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: David Woods <dwoods@ezchip.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-21 17:26:00 +00:00

87 lines
2.3 KiB
C

/*
* arch/arm64/include/asm/hugetlb.h
*
* Copyright (C) 2013 Linaro Ltd.
*
* Based on arch/x86/include/asm/hugetlb.h
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef __ASM_HUGETLB_H
#define __ASM_HUGETLB_H
#include <asm-generic/hugetlb.h>
#include <asm/page.h>
static inline pte_t huge_ptep_get(pte_t *ptep)
{
return *ptep;
}
static inline void hugetlb_free_pgd_range(struct mmu_gather *tlb,
unsigned long addr, unsigned long end,
unsigned long floor,
unsigned long ceiling)
{
free_pgd_range(tlb, addr, end, floor, ceiling);
}
static inline int is_hugepage_only_range(struct mm_struct *mm,
unsigned long addr, unsigned long len)
{
return 0;
}
static inline int prepare_hugepage_range(struct file *file,
unsigned long addr, unsigned long len)
{
struct hstate *h = hstate_file(file);
if (len & ~huge_page_mask(h))
return -EINVAL;
if (addr & ~huge_page_mask(h))
return -EINVAL;
return 0;
}
static inline int huge_pte_none(pte_t pte)
{
return pte_none(pte);
}
static inline pte_t huge_pte_wrprotect(pte_t pte)
{
return pte_wrprotect(pte);
}
static inline void arch_clear_hugepage_flags(struct page *page)
{
clear_bit(PG_dcache_clean, &page->flags);
}
extern pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
struct page *page, int writable);
#define arch_make_huge_pte arch_make_huge_pte
extern void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte);
extern int huge_ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep,
pte_t pte, int dirty);
extern pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep);
extern void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep);
extern void huge_ptep_clear_flush(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep);
#endif /* __ASM_HUGETLB_H */