diff options
Diffstat (limited to 'arch/x86/mm/gup.c')
| -rw-r--r-- | arch/x86/mm/gup.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c index 738e6593799..06f56fcf9a7 100644 --- a/arch/x86/mm/gup.c +++ b/arch/x86/mm/gup.c @@ -105,6 +105,16 @@ static inline void get_head_page_multiple(struct page *page, int nr) atomic_add(nr, &page->_count); } +static inline void get_huge_page_tail(struct page *page) +{ + /* + * __split_huge_page_refcount() cannot run + * from under us. + */ + VM_BUG_ON(atomic_read(&page->_count) < 0); + atomic_inc(&page->_count); +} + static noinline int gup_huge_pmd(pmd_t pmd, unsigned long addr, unsigned long end, int write, struct page **pages, int *nr) { @@ -128,6 +138,8 @@ static noinline int gup_huge_pmd(pmd_t pmd, unsigned long addr, do { VM_BUG_ON(compound_head(page) != head); pages[*nr] = page; + if (PageTail(page)) + get_huge_page_tail(page); (*nr)++; page++; refs++; |