From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: Re: [PATCH 15/21] lpfc: Implement support for wire-only DIF devices Date: Tue, 07 Apr 2015 19:13:03 -0400 Message-ID: References: <1428095580.6933.44.camel@myfc17> <20150405160613.GA8622@infradead.org> Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:25184 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754522AbbDGXNg (ORCPT ); Tue, 7 Apr 2015 19:13:36 -0400 In-Reply-To: <20150405160613.GA8622@infradead.org> (Christoph Hellwig's message of "Sun, 5 Apr 2015 09:06:13 -0700") Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Christoph Hellwig Cc: James Smart , linux-scsi@vger.kernel.org, "Martin K. Petersen" >>>>> "Christoph" == Christoph Hellwig writes: >> This patch adds the ability to support auto-enablement of wire-only >> DIF (DIF is generated on TX to target, stripped on RX; OS unaware DIF >> in use) for a select set of devices. Currently, there is only 1 >> device vendor supported: 3PARdata. When the feature is enabled, >> Inquiry commands are trapped, the vendor matched, and DIF enablement >> checked. In 3Par's case, there's a vendor specific check to see if >> the LUN supports DIF. If supported, DIF will be enabled on a per-lun >> basis. The driver will trap READS/WRITEs from the OS, check for LUN >> DIF enablement, and if set, turns on write-only DIF. Christoph> NAK. We do support proper DIF, and anyone who wants it should Christoph> enable the real thing. Christoph> And even if we would want to support a hack like this we'd do Christoph> it genericly an not in a driver. Agree completely. -- Martin K. Petersen Oracle Linux Engineering