[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linux-scsi
Subject:    Re: [PATCH 04 of 10] scsi: Support devices with protection information (DIF)
From:       "Martin K. Petersen" <martin.petersen () oracle ! com>
Date:       2008-06-30 15:24:35
Message-ID: yq17ic7c5e4.fsf () sermon ! lab ! mkp ! net
[Download RAW message or body]

>>>>> "James" == James Bottomley <James.Bottomley@HansenPartnership.com> writes:

[Protection sgl alloc + init]

James> I'm afraid you can't do it like this because it will violate
James> our forward progress guarantees.  If this is the last spare
James> command required for writeout, you need to guarantee either
James> this allocation will succeed, or we can proceed without the DIF
James> data.

We can't just turn off DIF -- that would violate the integrity
guarantees.  But I'll move the protection sgl to the host command
pool.



>> + if (inq_result[5] & 0x1) + sdev->protection = 1;

James> Is there a reason to have a separate flag here

Not really.  I used to key off of sdp->protection quite a bit but I
think the only place I use it now is during sd discovery.  So this can
simply go away...

-- 
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@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
[prev in list] [next in list] [prev in thread] [next in thread]