BLKDEV_DISCARD_SECURE   40 block/blk-lib.c 	if (flags & BLKDEV_DISCARD_SECURE) {
BLKDEV_DISCARD_SECURE  529 block/ioctl.c  				BLKDEV_DISCARD_SECURE);
BLKDEV_DISCARD_SECURE 1034 drivers/block/xen-blkback/blkback.c 		 BLKDEV_DISCARD_SECURE : 0;