On Fri, Jan 22, 2021 at 11:42:51PM +0100, David Disseldorp wrote: > On Wed, 20 Jan 2021 13:27:00 +0300, Dmitry Bogdanov wrote: > > > Now REPORT LUNS for software device servers always reports all luns > > regardless of SELECT REPORT field. > > Add handling of that field according to SPC-4: > > * accept known values, > > * reject unknown values. > > We currently advertise SPC-3 VERSION compliance via standard INQUIRY > data, so I think we should either support SPC-3 SELECT REPORT values or > bump the VERSION field (SPC-4 behaviour is already scattered throughout > LIO). > Out of curiosity, do you know of any initiators which use this field? > Hi David, SELECT REPORT field can be used for vVOL (LU conglomerate) discovery and for well-known lun listing. The field is used by VMware ESXi: https://support.purestorage.com/Solutions/VMware_Platform_Guide/User_Guides_for_VMware_Solutions/Virtual_Volumes_User_Guide/vVols_User_Guide%3A_Protocol_Endpoints "PEs greatly extend the number of vVols that can be connected to an ESXi cluster; each PE can have up to 16,383 vVols per host bound to it simultaneously. Moreover, a new binding does not require a complete I/O rescan. Instead, ESXi issues a REPORT_LUNS SCSI command with SELECT REPORT to the PE to which the sub-lun is bound. The PE returns a list of sub-lun IDs for the vVols bound to that host. In large clusters, REPORT_LUNS is significantly faster than a full I/O rescan because it is more precisely targeted." The post also confirms that: https://sourceforge.net/p/scst/mailman/message/33030432/ A few more targets that support SELECT REPORT field below. Sun/Oracle tape library: https://docs.oracle.com/en/storage/tape-storage/storagetek-sl150-modular-tape-library/slorm/report-luns-a0h.html#GUID-4140F40D-BD9A-495C-9A86-8BD7E91C985C IBM Flash Storage: https://www.ibm.com/support/pages/sites/default/files/support/ssg/ssgdocs.nsf/0/95d7115d7eb428e485257f80005cc3a7/%24FILE/FlashSystem_840_SCSI_Interface_Manual_1.2.pdf With regards to bumping TCM to SPC-4, are there any objections if we submit a separate patch for that? Or resubmit a series with the patch? Thanks, Roman
