Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751707AbaANOxi (ORCPT ); Tue, 14 Jan 2014 09:53:38 -0500 Received: from mo4-p04-ob.smtp.rzone.de ([81.169.146.179]:44546 "EHLO mo4-p04-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751318AbaANOxf (ORCPT ); Tue, 14 Jan 2014 09:53:35 -0500 X-RZG-CLASS-ID: mo04 X-RZG-AUTH: :P2EQZWCpfu+qG7CngxMFH1J+yackYocTD1iAi8x+OWJ4Kkzc/qnW2/7rNbk= Date: Tue, 14 Jan 2014 15:53:28 +0100 From: Olaf Hering To: David Vrabel Cc: Jan Beulich , Ian Campbell , xen-devel@lists.xen.org, boris.ostrovsky@oracle.com, linux-kernel@vger.kernel.org Subject: Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard Message-ID: <20140114145328.GA12888@aepfle.de> References: <1389608052-7139-1-git-send-email-olaf@aepfle.de> <52D3DAEE0200007800112FD4@nat28.tlf.novell.com> <20140113120131.GA15623@aepfle.de> <52D3EB5F02000078001130B5@nat28.tlf.novell.com> <1389618054.13654.57.camel@kazak.uk.xensource.com> <52D3F535020000780011311B@nat28.tlf.novell.com> <52D3EE14.3080609@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <52D3EE14.3080609@citrix.com> User-Agent: Mutt/1.5.22.rev6346 (2013-10-29) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 13, David Vrabel wrote: > Can we have a patch to blkif.h that clarifies this? What about this change? diff --git a/xen/include/public/io/blkif.h b/xen/include/public/io/blkif.h index 84eb7fd..56e2faa 100644 --- a/xen/include/public/io/blkif.h +++ b/xen/include/public/io/blkif.h @@ -194,6 +194,7 @@ * discard-secure * Values: 0/1 (boolean) * Default Value: 0 + * Notes: 10 * * A value of "1" indicates that the backend can process BLKIF_OP_DISCARD * requests with the BLKIF_DISCARD_SECURE flag set. @@ -323,9 +324,10 @@ * For full interoperability, block front and backends should publish * identical ring parameters, adjusted for unit differences, to the * XenStore nodes used in both schemes. - * (4) Devices that support discard functionality may internally allocate - * space (discardable extents) in units that are larger than the - * exported logical block size. + * (4) Devices that support discard functionality may internally allocate space + * (discardable extents) in units that are larger than the exported logical + * block size. The properties discard-granularity and discard-alignment may + * be present if the backing device has such requirments. * (5) The discard-alignment parameter allows a physical device to be * partitioned into virtual devices that do not necessarily begin or * end on a discardable extent boundary. @@ -344,6 +346,8 @@ * grants that can be persistently mapped in the frontend driver, but * due to the frontent driver implementation it should never be bigger * than RING_SIZE * BLKIF_MAX_SEGMENTS_PER_REQUEST. + *(10) The discard-secure property may be present and will be set to 1 if the + * backing device supports secure discard. */ /* Olaf -- 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/