>>>>> "Shaun" == Shaun Tancheff <shaun@xxxxxxxxxxxx> writes: Shaun> SATA drives may support write same via SCT. This is useful for Shaun> setting the drive contents to a specific pattern (0's). As indicated a while back, my preference would be for you to add support for REPORT SUPPORTED OPERATION CODES. It's fine that you keep the RSOC response simple and only list WRITE SAME(10/16). But I want to avoid having different heuristics for libata's SCSI-ATA translation and for hardware controller ditto. Shaun> If UNMAP is not set or TRIM is not available Please do not conflate the two. We have the appropriate fallbacks at the block layer. It happens to be the same command descriptor but it is two very different implementations at the device level. If the UNMAP bit is set you need to issue a DSM TRIM. If the device does not support TRIM you need to return ILLEGAL REQUEST/INVALID FIELD IN CDB. If the UNMAP bit is not set then it's a regular WRITE SAME and should be issued using SCT WRITE SAME. If the device does not support SCT WRITE SAME you need to return ILLEGAL REQUEST/INVALID FIELD IN CDB. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
