@@ -124,6 +124,9 @@ 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,
@@ -382,6 +382,13 @@ 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);
+ }
+
if (is_hugepd(__hugepd(pgd_val(*pgd)))) {
page = follow_huge_pd(vma, address,
__hugepd(pgd_val(*pgd)), flags,
@@ -4702,6 +4702,15 @@ 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
/*
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. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> --- include/linux/hugetlb.h | 3 +++ mm/gup.c | 7 +++++++ mm/hugetlb.c | 9 +++++++++ 3 files changed, 19 insertions(+)