From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:51805) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QotAV-0006rC-QG for qemu-devel@nongnu.org; Thu, 04 Aug 2011 04:20:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QotAU-0004el-PX for qemu-devel@nongnu.org; Thu, 04 Aug 2011 04:20:39 -0400 Received: from e23smtp06.au.ibm.com ([202.81.31.148]:35142) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QotAU-0004dI-38 for qemu-devel@nongnu.org; Thu, 04 Aug 2011 04:20:38 -0400 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [202.81.31.247]) by e23smtp06.au.ibm.com (8.14.4/8.13.1) with ESMTP id p748JZJf019573 for ; Thu, 4 Aug 2011 18:19:35 +1000 Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p748JXEv901172 for ; Thu, 4 Aug 2011 18:19:33 +1000 Received: from d23av02.au.ibm.com (loopback [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p748KOHs014554 for ; Thu, 4 Aug 2011 18:20:24 +1000 Message-ID: <4E3A590B.1080609@linux.vnet.ibm.com> Date: Thu, 04 Aug 2011 14:02:11 +0530 From: Supriya Kannery MIME-Version: 1.0 References: <20110727113000.25109.16204.sendpatchset@skannery> <20110727113045.25109.54866.sendpatchset@skannery> <4E300B8E.2020509@codemonkey.ws> <4E3036AA.8030604@codemonkey.ws> <4E36C608.2030107@codemonkey.ws> <4E36C9D3.4020803@redhat.com> <4E36C9F4.2080202@codemonkey.ws> In-Reply-To: <4E36C9F4.2080202@codemonkey.ws> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [V5 Patch 3/4]Qemu: Command "block_set" for dynamic block params change Reply-To: supriyak@linux.vnet.ibm.com List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: Kevin Wolf , Stefan Hajnoczi , Christoph Hellwig , qemu-devel@nongnu.org On 08/01/2011 09:14 PM, Anthony Liguori wrote: > On 08/01/2011 10:44 AM, Kevin Wolf wrote: >> Am 01.08.2011 17:28, schrieb Anthony Liguori: >>>> 2. Top-level command for each parameter (e.g. block_set_hostcache). >>>> Supported parameters are easily discoverable via query-commands. If >>>> individual block devices support different sets of parameters then >>>> they may have to return -ENOTSUPP. >>>> >>>> I like the block_set approach. >>>> >>>> Anthony, Kevin, Supriya: Any thoughts? >>> >>> For the sake of overall QMP sanity, I think block_set_hostcache is >>> really our only option. >> >> Ideally we should have blockdev_add, and blockdev_set would just take >> the same arguments and update the given driver. > > Ideally we'd have a backend_add, backend_set, etc. > > But in the absence of that, we should provide the best interface we can > with the current tools we have. > > For now, using high level commands is the best we can do. Will be modifying code to have 'block_set_hostcache' command implemented. Along with that, planning to implement 'query-block_set_hostcache', that returns current hostcache setting for all the applicable block devices. I am not able to find how "query-commands" is helping out to programmatically find out all the supported parameters of a specific command. When I tried out, "query-commands" is listing all the supported command names. "query-xx" is returning current settings related to command 'xx', but not any information related to supported parameters of 'xx'. Am I missing something? > > Regards, > > Anthony Liguori > >> >> But we don't have blockdev_add today, so whatever works for your as a >> temporary solution... >> >> Kevin >> > >