From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [RFC] training mpath to discern between SCSI errors Date: Mon, 30 Aug 2010 16:07:48 +0400 Message-ID: <4C7B9F14.9080900@mvista.com> References: <20100825155918.GB8509@redhat.com> <4C7B984E.4070802@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4C7B984E.4070802@suse.de> Sender: linux-ide-owner@vger.kernel.org To: Hannes Reinecke Cc: Mike Snitzer , Kiyoshi Ueda , Tejun Heo , michaelc@cs.wisc.edu, James.Bottomley@suse.de, tytso@mit.edu, linux-scsi@vger.kernel.org, jaxboe@fusionio.com, jack@suse.cz, linux-kernel@vger.kernel.org, swhiteho@redhat.com, linux-raid@vger.kernel.org, linux-ide@vger.kernel.org, konishi.ryusuke@lab.ntt.co.jp, linux-fsdevel@vger.kernel.org, vst@vlnb.net, rwheeler@redhat.com, Christoph Hellwig , chris.mason@oracle.com, dm-devel@redhat.com List-Id: dm-devel.ids Hello. Hannes Reinecke wrote: > Actually, I think we have two separate issues here: > 1) The need of having more detailed I/O errors even in the fs layer. This > we've already discussed at the LSF, consensus here is to allow other > errors than just 'EIO'. > Instead of Mike's approach I would rather use existing error codes here; > this will make the transition somewhat easier. > Initially I would propose to return 'ENOLINK' for a transport failure, > 'EIO' for a non-retryable failure on the target, and 'ENODEV' for a > retryable failure on the target. Are you sure it's not vice versa: EIO for retryable and ENODEV for non-retryable failures. ENODEV looks more like permanent condition to me. WBR, Sergei