Commit faaa5b62 authored by Anshuman Khandual's avatar Anshuman Khandual Committed by Linus Torvalds
Browse files

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: default avatarAnshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: default avatarAneesh 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d5ed7444

include/linux/hugetlb.h

+4 −0
Original line number Diff line number Diff line
@@ -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

mm/gup.c

+7 −0
Original line number Diff line number Diff line
@@ -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);

}

mm/hugetlb.c

+9 −0
Original line number Diff line number Diff line
@@ -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



/*

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