Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934304AbaGYQ57 (ORCPT ); Fri, 25 Jul 2014 12:57:59 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:33330 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932508AbaGYQ54 (ORCPT ); Fri, 25 Jul 2014 12:57:56 -0400 To: KY Srinivasan Cc: "Martin K. Petersen" , Sitsofe Wheeler , Christoph Hellwig , "gregkh\@linuxfoundation.org" , "linux-kernel\@vger.kernel.org" , "devel\@linuxdriverproject.org" , "ohering\@suse.com" , "apw\@canonical.com" , "jasowang\@redhat.com" , "jbottomley\@parallels.com" , "linux-scsi\@vger.kernel.org" Subject: Re: [PATCH v2 3/3] [SCSI] Make LBP quirk skip lbpme checks tests From: "Martin K. Petersen" Organization: Oracle Corporation References: <20140724122223.GA31798@sucs.org> <20140724153612.GA23648@sucs.org> <16fea5bb87ba47019527cee788e07a72@BY2PR0301MB0711.namprd03.prod.outlook.com> Date: Fri, 25 Jul 2014 12:57:02 -0400 In-Reply-To: <16fea5bb87ba47019527cee788e07a72@BY2PR0301MB0711.namprd03.prod.outlook.com> (KY Srinivasan's message of "Fri, 25 Jul 2014 16:47:35 +0000") Message-ID: User-Agent: Gnus/5.130012 (Ma Gnus v0.12) Emacs/24.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>>>> "KY" == KY Srinivasan writes: KY> For the pass through case, the host validates the request and passes KY> the request to the device. However, not all scsi commands are KY> passed through even though the device it is being passed through may KY> support the command. WRITE_SAME is one such command. Consequently, KY> in the EVPD page, we will set state indicating that WRITE_SAME is KY> not supported (even if the device supports it). The LBP VPD page flags UNMAP as being supported. Do you actually support UNMAP to DSM TRIM SCSI-ATA translation? One challenge in that department is that a single UNMAP command may turn into many, many, many DSM TRIM commands on the underlying SATA device. That's why we went with WRITE SAME for the internal Linux SATL, capping the maximum number of blocks to what we can fit in a single DSM TRIM command. -- 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/