ceph: Don't add dirty inode to dirty list if caps is in migration

Add dirty inode to cap_dirty_migrating list instead, this can avoid
ceph_flush_dirty_caps() entering infinite loop.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Sage Weil <sage@inktank.com>

fs/ceph/caps.c

@@ -1351,11 +1351,15 @@ int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
 		if (!ci->i_head_snapc)
 			ci->i_head_snapc = ceph_get_snap_context(
 				ci->i_snap_realm->cached_context);
-		dout(" inode %p now dirty snapc %p\n", &ci->vfs_inode,
-			ci->i_head_snapc);
+		dout(" inode %p now dirty snapc %p auth cap %p\n",
+		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
 		BUG_ON(!list_empty(&ci->i_dirty_item));
 		spin_lock(&mdsc->cap_dirty_lock);
-		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
+		if (ci->i_auth_cap)
+			list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
+		else
+			list_add(&ci->i_dirty_item,
+				 &mdsc->cap_dirty_migrating);
 		spin_unlock(&mdsc->cap_dirty_lock);
 		if (ci->i_flushing_caps == 0) {
 			ihold(inode);