2 files changed, 6 insertions, 4 deletions

diff --git a/include/linux/idr.h b/include/linux/idr.h
index 7d6a6313f0ab..913c335054f0 100644
--- a/include/linux/idr.h
+++ b/include/linux/idr.h
@@ -29,7 +29,8 @@ struct idr {
 #define IDR_FREE        0
 
 /* Set the IDR flag and the IDR_FREE tag */
-#define IDR_RT_MARKER           ((__force gfp_t)(3 << __GFP_BITS_SHIFT))
+#define IDR_RT_MARKER   (ROOT_IS_IDR | (__force gfp_t)                  \
+                                        (1 << (ROOT_TAG_SHIFT + IDR_FREE)))
 
 #define IDR_INIT_BASE(base) {                                           \
         .idr_rt = RADIX_TREE_INIT(IDR_RT_MARKER),                       \
diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h
index fc55ff31eca7..6c4e2e716dac 100644
--- a/include/linux/radix-tree.h
+++ b/include/linux/radix-tree.h
@@ -104,9 +104,10 @@ struct radix_tree_node {
         unsigned long   tags[RADIX_TREE_MAX_TAGS][RADIX_TREE_TAG_LONGS];
 };
 
-/* The top bits of gfp_mask are used to store the root tags and the IDR flag */
-#define ROOT_IS_IDR     ((__force gfp_t)(1 << __GFP_BITS_SHIFT))
-#define ROOT_TAG_SHIFT  (__GFP_BITS_SHIFT + 1)
+/* The IDR tag is stored in the low bits of the GFP flags */
+#define ROOT_IS_IDR     ((__force gfp_t)4)
+/* The top bits of gfp_mask are used to store the root tags */
+#define ROOT_TAG_SHIFT  (__GFP_BITS_SHIFT)
 
 struct radix_tree_root {
         gfp_t                   gfp_mask;