From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sagi Grimberg <sagig@dev.mellanox.co.il>
Subject: Re: Crash on WRITE SAME
Date: Thu, 03 Jul 2014 10:33:59 +0300
Message-ID: <53B50767.2010209@dev.mellanox.co.il>
References: <alpine.LRH.2.02.1407021338550.20183@file01.intranet.prod.int.rdu2.redhat.com> <20140702181333.GA15792@infradead.org> <alpine.LRH.2.02.1407021423240.20183@file01.intranet.prod.int.rdu2.redhat.com> <20140702183607.GA19117@infradead.org>
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To: Christoph Hellwig <hch@infradead.org>, Mikulas Patocka <mpatocka@redhat.com>
Cc: Sagi Grimberg <sagig@mellanox.com>, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Mike Christie <michaelc@cs.wisc.edu>, Nicholas Bellinger <nab@linux-iscsi.org>
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On 7/2/2014 9:36 PM, Christoph Hellwig wrote:
> On Wed, Jul 02, 2014 at 02:29:05PM -0400, Mikulas Patocka wrote:
>> And what about protection information for commands that transfer partial
>> sectors? (for example, UMAP transfers 24 bytes). Should
>> scsi_transfer_length return 24 or 32 in this case?
> As far as I understand so far PI is only defined for READ/WRITE
> commands.  But I'll defer to Martin who is a much better source for
> information on this topic.

hch is correct, PI supported operations are (stated in SBC)

a) COMPARE AND WRITE;
b) ORWRITE (16);
c) ORWRITE (32);
d) READ (10);
e) READ (12);
f) READ (16);
g) READ (32);
h) VERIFY (10);
i) VERIFY (12);
j) VERIFY (16);
k) VERIFY (32);
l) WRITE (10);
m) WRITE (12);
n) WRITE (16);
o) WRITE (32);
p) WRITE AND VERIFY (10);
q) WRITE AND VERIFY (12);
r) WRITE AND VERIFY (16);
s) WRITE AND VERIFY (32);
t) WRITE SAME (10);
u) WRITE SAME (16);
v) WRITE SAME (32);
y) XDWRITEREAD (10);
z) XDWRITEREAD (32);
aa) XPWRITE (10); and
ab) XPWRITE (32).

Sagi.