From: Theodore Ts'o Subject: Re: [v6 2/4] ext4: adds project ID support Date: Mon, 10 Nov 2014 23:26:06 -0500 Message-ID: <20141111042606.GA17027@thunk.org> References: <1415468619-31851-1-git-send-email-lixi@ddn.com> <1415468619-31851-3-git-send-email-lixi@ddn.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, adilger-m1MBpc4rdrD3fQ9qLvQP4Q@public.gmane.org, jack-AlSwsSmVLrQ@public.gmane.org, viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org, hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, dmonakhov-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org To: Li Xi Return-path: Content-Disposition: inline In-Reply-To: <1415468619-31851-3-git-send-email-lixi-LfVdkaOWEx8@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-ext4.vger.kernel.org On Sun, Nov 09, 2014 at 01:43:37AM +0800, Li Xi wrote: > This patch adds a new internal field of ext4 inode to save project > identifier. Also a new flag EXT4_INODE_PROJINHERIT is added for > inheriting project ID from parent directory. What would be the downside of simply always inhereiting the project ID from the parent directory? I see that if the flag is not set, the project id will be 0 instead. I'm not sure when that would actually be desirable. To the extent that the project ID is designed to implement a quota over a directory extent, the fact that the owner can clear the EXT4_PROJINHERET_FL and then arrange to have the quota charged to project 0 seems to me to be a bug, not a feature. Can you explain what your intended use case for this flag might be? Thanks, - Ted