[PATCH v2 3/3] [SCSI] Make LBP quirk skip lbpme checks tests

Martin K. Petersen martin.petersen at oracle.com
Mon Jul 28 19:02:46 UTC 2014


>>>>> "KY" == KY Srinivasan <kys at microsoft.com> writes:

KY,

KY> "At the time thin-provisioning was defined, the discovery
KY> information was first proposed in READ CAPACITY 16 command. And then
KY> moved into the new dedicated VPD page - B2h. You can see the
KY> information reported in this VPD page is richer than READ CAPACITY
KY> 16 command. As this transition happened during we added the feature,
KY> Windows uses the newer method that based on VPD page B2h. It looks
KY> Linux tries to use both new and old method which is weird to me."

The READ CAPACITY(16) response is not optional.

SBC3r36 section 4.7.3.3 Thin provisioned logical unit:

The device server in a thin provisioned logical unit shall set:

a) the LBPME bit to one in the READ CAPACITY (16) parameter data (see
   5.16.2); and

b) the PROVISIONING TYPE field to 010b (i.e., thin provisioned) in the
   Logical Block Provisioning VPD page (see 6.6.4).

That's a "shall". The LBP VPD elaborates on the provisioning type,
commands preference, etc. But it's all gated by LBPME=1 in the READ
CAPACITY(16) response.

-- 
Martin K. Petersen	Oracle Linux Engineering


More information about the devel mailing list