On Tue, 2017-10-10 at 17:29 +0200, Johannes Thumshirn wrote: > Call set_host_byte() instead of open-coding it. > > Converted using this simple Coccinelle spatch > > <SmPL> > @@ > local idexpression struct scsi_cmnd *c; > expression E1; > @@ > > - c->result = E1 << 16; > + set_host_byte(c, E1); > </SmPL> This is useful but I think we should take this a step further. How about the following approach: - Introduce four enumeration types - one for the msg byte codes, one for the host byte codes, one for the driver byte codes and one for SCSI sense codes. - Update the signatures of functions that store or extract these four bytes. - Change the data type of scsi_cmnd.result into something that makes regular assignments trigger a compiler error. I'm proposing this because there are several drivers that do not assign the SCSI host byte correctly: $ git grep -nH '>result = DID_' | grep -v '<< *16' | grep -v ': \*' drivers/scsi/ips.c:953: scsi_cmd->result = DID_ERROR; drivers/scsi/ips.c:2657: SC->result = DID_OK; drivers/scsi/libiscsi.c:1731: sc->result = DID_REQUEUE; drivers/scsi/qla2xxx/qla_bsg.c:152: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:167: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:184: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:236: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:976: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:1078: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:1261: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:1375: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:1480: bsg_reply->result = DID_OK; drivers/scsi/qla2xxx/qla_bsg.c:1516: bsg_reply->result = DID_OK; drivers/scsi/qlogicpti.c:1049: Cmnd->result = DID_BUS_BUSY; drivers/scsi/stex.c:615: cmd->result = DID_NO_CONNECT; Bart.