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>
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 1c53c7d..70587ea 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -155,6 +155,16 @@
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; })