From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: Re: [patch v2] bio-integrity: use hardware sectors instead of block layer sectors Date: Mon, 17 May 2010 15:06:00 -0400 Message-ID: References: <20100507082928.GT27064@bicker> <20100507095414.GH27064@bicker> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Martin K. Petersen" , Jens Axboe , Chuck Ebbert , linux-fsdevel@vger.kernel.org, Alexander Viro , kernel-janitors@vger.kernel.org To: Dan Carpenter Return-path: Received: from rcsinet10.oracle.com ([148.87.113.121]:57083 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755299Ab0EQTG0 (ORCPT ); Mon, 17 May 2010 15:06:26 -0400 In-Reply-To: <20100507095414.GH27064@bicker> (Dan Carpenter's message of "Fri, 7 May 2010 11:54:14 +0200") Sender: linux-fsdevel-owner@vger.kernel.org List-ID: >>>>> "Dan" == Dan Carpenter writes: Dan, This one bitrotted in my mailbox for a while because it conflicted with something else I was working on and then it slipped through the cracks. Sorry about that. Dan> The difference between "sectors" and "nr_sectors" is that "sectors" Dan> is in terms of 512 byte sectors and "nr_sectors" is in terms of Dan> hardware sectors. They are only different for 4k sector devices. Dan> Also I changed the name because as Jamie Lokier points out, "that Dan> code is so asking for the variable to be called 'hw_sectors'." The change is obviously functionally correct. But I object to the notion of hw_sectors. The 1:1 mapping of DIF tuples and logical blocks is even going away in SBC3. So let's not perpetuate that. I have a patch in my queue that gets rid of all the hw_sector references in the integrity code. I'll make sure to include your fix. So thanks for spotting this. I obviously haven't tested PI drives with a 4KB logical block size in combination with device mapper... -- Martin K. Petersen Oracle Linux Engineering