mm/follow_page_mask: add support for hugetlb pgd entries

ppc64 supports pgd hugetlb entries.  Add code to handle hugetlb pgd
entries to follow_page_mask so that ppc64 can switch to it to handle
hugetlbe entries.

Link: http://lkml.kernel.org/r/1494926612-23928-5-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Anshuman Khandual 2017-07-06 15:38:50 -07:00 committed by Linus Torvalds
parent d5ed7444da
commit faaa5b62d3
3 changed files with 20 additions and 0 deletions

View File

@ -121,6 +121,9 @@ struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
pmd_t *pmd, int flags);
struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address,
pud_t *pud, int flags);
struct page *follow_huge_pgd(struct mm_struct *mm, unsigned long address,
pgd_t *pgd, int flags);
int pmd_huge(pmd_t pmd);
int pud_huge(pud_t pud);
unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
@ -150,6 +153,7 @@ static inline void hugetlb_show_meminfo(void)
}
#define follow_huge_pmd(mm, addr, pmd, flags) NULL
#define follow_huge_pud(mm, addr, pud, flags) NULL
#define follow_huge_pgd(mm, addr, pgd, flags) NULL
#define prepare_hugepage_range(file, addr, len) (-EINVAL)
#define pmd_huge(x) 0
#define pud_huge(x) 0

View File

@ -357,6 +357,13 @@ struct page *follow_page_mask(struct vm_area_struct *vma,
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
return no_page_table(vma, flags);
if (pgd_huge(*pgd)) {
page = follow_huge_pgd(mm, address, pgd, flags);
if (page)
return page;
return no_page_table(vma, flags);
}
return follow_p4d_mask(vma, address, pgd, flags, page_mask);
}

View File

@ -4715,6 +4715,15 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address,
return pte_page(*(pte_t *)pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT);
}
struct page * __weak
follow_huge_pgd(struct mm_struct *mm, unsigned long address, pgd_t *pgd, int flags)
{
if (flags & FOLL_GET)
return NULL;
return pte_page(*(pte_t *)pgd) + ((address & ~PGDIR_MASK) >> PAGE_SHIFT);
}
#ifdef CONFIG_MEMORY_FAILURE
/*