Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751437AbaALMeB (ORCPT ); Sun, 12 Jan 2014 07:34:01 -0500 Received: from aserp1040.oracle.com ([141.146.126.69]:33731 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751224AbaALMd5 (ORCPT ); Sun, 12 Jan 2014 07:33:57 -0500 To: Sagi Grimberg Cc: "Martin K. Petersen" , Sagi Grimberg , "Nicholas A. Bellinger" , target-devel , linux-scsi , linux-kernel , Christoph Hellwig , Hannes Reinecke , Or Gerlitz , Nicholas Bellinger Subject: Re: [PATCH 07/14] target/sbc: Add P_TYPE + PROT_EN bits to READ_CAPACITY_16 From: "Martin K. Petersen" Organization: Oracle Corporation References: <1389212157-14540-1-git-send-email-nab@daterainc.com> <1389212157-14540-8-git-send-email-nab@daterainc.com> <52CE78EB.60108@mellanox.com> <52D286D9.5050500@dev.mellanox.co.il> Date: Sun, 12 Jan 2014 07:33:40 -0500 In-Reply-To: <52D286D9.5050500@dev.mellanox.co.il> (Sagi Grimberg's message of "Sun, 12 Jan 2014 14:13:13 +0200") Message-ID: User-Agent: Gnus/5.130005 (Ma Gnus v0.5) Emacs/24.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>>>> "Sagi" == Sagi Grimberg writes: >> I don't know of any non-disk devices that actually implement FORMAT >> UNIT. Usually such configuration is done using the array management >> interface. Sagi> So this takes me to a corner I still don't understand, if a LUN is Sagi> pre-formatted as T10-protected, what happens to unwritten blocks Sagi> read? I mean, SCSI login executes some reads from sevel LBAs Sagi> which will probably fail as blocks are unwritten. Per SBC, PI must be initialized to 0xffffffffffffffff. Since an app tag value of 0xffff is an escape, this will prevent both target and initiator from performing PI-verification when that block is read. If a block is subsequently written and no PI is sent from the host (WRPROTECT=0), the target must generate valid PI for each block. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/