ceph: use I_COMPLETE inode flag instead of D_COMPLETE flag

commit c6ffe10015 moved the flag that tracks if the dcache contents
for a directory are complete to dentry. The problem is there are
lots of places that use ceph_dir_{set,clear,test}_complete() while
holding i_ceph_lock. but ceph_dir_{set,clear,test}_complete() may
sleep because they call dput().

This patch basically reverts that commit. For ceph_d_prune(), it's
called with both the dentry to prune and the parent dentry are
locked. So it's safe to access the parent dentry's d_inode and
clear I_COMPLETE flag.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index ea1f177..bc575a4 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -490,15 +490,17 @@
 		ci->i_rdcache_gen++;
 
 	/*
-	 * if we are newly issued FILE_SHARED, clear D_COMPLETE; we
+	 * if we are newly issued FILE_SHARED, clear I_COMPLETE; we
 	 * don't know what happened to this directory while we didn't
 	 * have the cap.
 	 */
 	if ((issued & CEPH_CAP_FILE_SHARED) &&
 	    (had & CEPH_CAP_FILE_SHARED) == 0) {
 		ci->i_shared_gen++;
-		if (S_ISDIR(ci->vfs_inode.i_mode))
-			ceph_dir_clear_complete(&ci->vfs_inode);
+		if (S_ISDIR(ci->vfs_inode.i_mode)) {
+			dout(" marking %p NOT complete\n", &ci->vfs_inode);
+			ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
+		}
 	}
 }