ceph: use new D_COMPLETE dentry flag

We used to use a flag on the directory inode to track whether the dcache
contents for a directory were a complete cached copy.  Switch to a dentry
flag CEPH_D_COMPLETE that is safely updated by ->d_prune().

Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 98e6069..01bf189 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -264,7 +264,7 @@
 	struct timespec i_rctime;
 	u64 i_rbytes, i_rfiles, i_rsubdirs;
 	u64 i_files, i_subdirs;
-	u64 i_max_offset;  /* largest readdir offset, set with I_COMPLETE */
+	u64 i_max_offset;  /* largest readdir offset, set with D_COMPLETE */
 
 	struct rb_root i_fragtree;
 	struct mutex i_fragtree_mutex;
@@ -429,7 +429,6 @@
 /*
  * Ceph inode.
  */
-#define CEPH_I_COMPLETE  1  /* we have complete directory cached */
 #define CEPH_I_NODELAY   4  /* do not delay cap release */
 #define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
 #define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
@@ -487,6 +486,13 @@
 }
 
 /*
+ * set/clear directory D_COMPLETE flag
+ */
+void ceph_dir_set_complete(struct inode *inode);
+void ceph_dir_clear_complete(struct inode *inode);
+bool ceph_dir_test_complete(struct inode *inode);
+
+/*
  * caps helpers
  */
 static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)