mm: export various functions for the benefit of DAX

To use the huge zero page in DAX, we need these functions exported.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Matthew Wilcox 2015-09-08 14:58:51 -07:00 committed by Linus Torvalds
parent b96375f74a
commit fc43704437
2 changed files with 11 additions and 6 deletions

View File

@ -155,6 +155,16 @@ static inline bool is_huge_zero_page(struct page *page)
return ACCESS_ONCE(huge_zero_page) == page;
}
static inline bool is_huge_zero_pmd(pmd_t pmd)
{
return is_huge_zero_page(pmd_page(pmd));
}
struct page *get_huge_zero_page(void);
bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long haddr,
pmd_t *pmd, struct page *zero_page);
#else /* CONFIG_TRANSPARENT_HUGEPAGE */
#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
#define HPAGE_PMD_MASK ({ BUILD_BUG(); 0; })

View File

@ -173,12 +173,7 @@ fail:
static atomic_t huge_zero_refcount;
struct page *huge_zero_page __read_mostly;
static inline bool is_huge_zero_pmd(pmd_t pmd)
{
return is_huge_zero_page(pmd_page(pmd));
}
static struct page *get_huge_zero_page(void)
struct page *get_huge_zero_page(void)
{
struct page *zero_page;
retry: