LU-3531 llite: move dir cache to MDC layer

[fs/lustre-release.git] / lustre / mdc / mdc_internal.h

diff --git a/lustre/mdc/mdc_internal.h b/lustre/mdc/mdc_internal.h
index c87d86f..cc2816b 100644 (file)
--- a/lustre/mdc/mdc_internal.h
+++ b/lustre/mdc/mdc_internal.h
@@ -173,4 +173,17 @@ static inline int mdc_prep_elc_req(struct obd_export *exp,
                                 count);
 }
 
+static inline unsigned long hash_x_index(__u64 hash, int hash64)
+{
+#ifdef __KERNEL__
+       if (BITS_PER_LONG == 32 && hash64)
+               hash >>= 32;
+#endif
+       /* save hash 0 as index 0 because otherwise we'll save it at
+        * page index end (~0UL) and it causes truncate_inode_pages_range()
+        * to loop forever.
+        */
+       return ~0UL - (hash + !hash);
+}
+
 #endif