1 files changed, 7 insertions, 0 deletions

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index a6c78e00ea96..26eabf5ec718 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -69,6 +69,13 @@ static inline gfp_t mapping_gfp_mask(struct address_space * mapping)
         return (__force gfp_t)mapping->flags & __GFP_BITS_MASK;
 }
 
+/* Restricts the given gfp_mask to what the mapping allows. */
+static inline gfp_t mapping_gfp_constraint(struct address_space *mapping,
+                gfp_t gfp_mask)
+{
+        return mapping_gfp_mask(mapping) & gfp_mask;
+}
+
 /*
  * This is non-atomic.  Only to be used before the mapping is activated.
  * Probably needs a barrier...