From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.15.19]:58205 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754511AbbIWNTt (ORCPT ); Wed, 23 Sep 2015 09:19:49 -0400 Subject: Re: [PATCH] btrfs: Fix no space bug caused by removing bg To: dsterba@suse.cz, Hugo Mills , =?UTF-8?Q?Holger_Hoffst=c3=a4tte?= , linux-btrfs@vger.kernel.org References: <15fc8f8d002e4ffcdb46e769736f240ae7ace20b.1442839332.git.zhaolei@cn.fujitsu.com> <560150CD.6070301@suse.com> <5601596B.1020607@googlemail.com> <20150922134131.GH5918@carfax.org.uk> <20150922142333.GH12815@twin.jikos.cz> <20150922143602.GI5918@carfax.org.uk> <20150923131226.GA12815@twin.jikos.cz> From: Qu Wenruo Message-ID: <5602A6EA.8050107@gmx.com> Date: Wed, 23 Sep 2015 21:19:38 +0800 MIME-Version: 1.0 In-Reply-To: <20150923131226.GA12815@twin.jikos.cz> Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: 在 2015年09月23日 21:12, David Sterba 写道: > On Tue, Sep 22, 2015 at 02:36:02PM +0000, Hugo Mills wrote: >>> Yeah, right now there's no persistent default for the allocator. I'm >>> still hoping that the object properties will magically solve that. >> >> There's no obvious place that filesystem-wide properties can be >> stored, though. There's a userspace tool to manipulate the few current >> FS-wide properties, but that's all special-cased to use the >> "historical" ioctls for those properties, with no generalisation of a >> property store, or even (IIRC) any external API for them. > > From the UI point, we proposed to add a specifier that would route the > property to either subvolume or the filesystem: > > $ btrfs prop set -t filesystem bgtype raid0 > $ btrfs prop set -t subvolume bgtype raid1 > BTW, is btrfs going to support different chunk/bg type for subvolume?! I thought data/meta/system chunk types are all per filesystem level, and was planning to use superblock to record it... If really to support that, does it mean we will have different meta/data type for each subvolume? That's a little too flex for me.... Thanks, Qu > How this will get stored in the xattrs is another question. As there's > always only single instance of the filesystem properties, it coud be > something like 'btrfs.fs.bgtype' and be stored as a xattr of the > toplevel subvolume. > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >