REQ_OP_BITS
BUILD_BUG_ON((__force u32)REQ_OP_LAST >= (1 << REQ_OP_BITS));
BUILD_BUG_ON(REQ_OP_BITS + REQ_FLAG_BITS > 8 *
BUILD_BUG_ON(REQ_OP_BITS + REQ_FLAG_BITS > 8 *
#define REQ_OP_MASK (__force blk_opf_t)((1 << REQ_OP_BITS) - 1)
REQ_OP_BITS,