From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: Re: [PATCH for xen-4.4] libxl: add option for discard support to xl disk configuration Date: Thu, 30 Jan 2014 18:30:58 +0100 Message-ID: <20140130173058.GA12133@aepfle.de> References: <1391083364-29483-1-git-send-email-olaf@aepfle.de> <20140130162558.GA9033@aepfle.de> <1391099505.9495.23.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1391099505.9495.23.camel@kazak.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: anthony.perard@citrix.com, George Dunlap , stefano.stabellini@eu.citrix.com, Ian.Jackson@eu.citrix.com, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On Thu, Jan 30, Ian Campbell wrote: > On Thu, 2014-01-30 at 17:25 +0100, Olaf Hering wrote: > > This change does not break ABI. Instead of adding a new member ->discard_enable > > to struct libxl_device_disk the existing ->readwrite member is reused. > Looks like it changes the libxlu ABI though. Or maybe that's totally > internal? DiskParseContext is used internal, there is no public header for it. > TBH -- if you (==suse I guess?) are contemplating carrying this as a > backport even before 4.4 is out the door we should probably be at least > considering a freeze exception for 4.4. George CCd for input. (I > appreciate that "backport=>freeze exception" is a potentially slippery > slope/ripe for abuse...) It will make less work for SUSE if this change would be incorporated into 4.4, and later replaced with the "final" version I sent out today. However, its small and will be easy to port forward to 4.4.X. The risk of including such change is small as it requires a patched qemu which actually does discard (1.7?), a patched frontend driver (pvops 3.15?) before the codepaths it enables are actually executed. Olaf