From: Dmitry Monakhov <dmonakhov@openvz.org>
Subject: Ping.
Date: Tue, 06 Apr 2010 13:00:58 +0400
Message-ID: <87ljd1vtth.fsf@openvz.org>
References: <1268920970-9061-1-git-send-email-dmonakhov@openvz.org>
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Cc: linux-fsdevel@vger.kernel.org, tytso@mit.edu, adilger@sun.com,
	hch@infradead.org, jack@suse.cz, david@fromorbit.com,
	viro@ZenIV.linux.org.uk, xemul@openvz.org
To: linux-ext4@vger.kernel.org
In-Reply-To: <1268920970-9061-1-git-send-email-dmonakhov@openvz.org> (Dmitry
	Monakhov's message of "Thu, 18 Mar 2010 17:02:45 +0300")
Sender: linux-ext4-owner@vger.kernel.org

Dmitry Monakhov <dmonakhov@openvz.org> writes:

> This is 6'th version of extened inode owner patch-set.
> Please review it tell me what do you think about all this.
>  Are you agree with this approach?
>  Are you worry about some implementation details?
>  Is it ready for merge to some devel's tree?
Ping. I haven't got response about the patchset, just small note about
xattr-name from Andreas.
Please clarify what do you think about whole idea and
current patch-set state. What do i have to do to make a progress?
>
> *Feature description*
> 1) Inode may has a project identifier which has same meaning as uid/gid.
> 2) Id is stored in inode's xattr named "system.project_id"
> 3) Id is inherent from parent inode on creation.
> 4) This id is cached in memory inode structure vfs_inode->i_prjid
>    This field it restricted by CONFIG_PROJECT_ID. So no wasting
>    of memory happens.
>
> 5) Since id is cached in memory it may be used for different purposes
>    such as:
> 5A) Implement additional quota id space orthogonal to uid/gid. This is
>     useful in managing quota for some filesystem hierarchy(chroot or
>     container over bindmount)
> 5B) Export dedicated fs hierarchy to nfsd (only inode which has some
>     project_id will be accessible via nfsd)
>
> 6) It is possible to create isolated project's subtree.
>    Note: Please do not blame isolation feature before you read the
>          isolation patch description, and than please wellcome.
>
> *User interface *
> Project id is managed via generic xattr interface "system.project_id"
> This good because
>  1) We may use already existing interface.
>  2) xattr already supported by generic urils tar/rsync and etc
>
> PATCH SET TOC:
> 1) generic projectid support
> 2) generic project quota support
> 3) ext4 project support implementation
>  3A) ext4: generic project support
>  3B) ext4: project quota support
>  3C) ext4: project isolation support. This patch is not principal
>            but makes ext4 implementation rename behaviour equotals
> 	   to XFS
>
> Patch against linux-next-20100318
> Changes against v5
>  - convert dquota_transfer to struct iattr interface. Not it is possible
>    to change i_prjid via notify_changes()
>  - some bugfixes.