From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Arendt Subject: Re: Default to read-only on snapshot creation and have a flag if snapshot should be writable (was: [PATCH 0/5] btrfs: Readonly snapshots) Date: Mon, 29 Nov 2010 21:41:08 +0100 Message-ID: <4CF40FE4.2030801@prnet.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Cc: linux-btrfs@vger.kernel.org To: Mike Fedyk Return-path: In-Reply-To: List-ID: On 11/29/10 21:02, Mike Fedyk wrote: > On Mon, Nov 29, 2010 at 12:02 AM, Li Zefan wrote: >> (Cc: Sage Weil for changes in async snapshots) >> >> This patchset adds readonly-snapshots support. You can create a >> readonly snapshot, and you can also set a snapshot readonly/writable >> on the fly. >> >> A few readonly checks are added in setattr, permission, remove_xattr >> and set_xattr callbacks, as well as in some ioctls. >> > Great work! > > I have a suggestion on defaults when snapshots are created. I think > they should default to being read-only and if they are meant to be > read-write a flag can be set at creation time (and changable at a > later time as well of course). > > This way user/admin preconceptions of a snapshot being read-only can > be enforced by default, and the exception when you want a read-write > snapshot can be available with a switch at the cli level (and probably > a flag at the ioctl level). > > It gives one more natural distinction between a snapshot and a > subvolume at the user conceptual level. > > What do you think? > -- > 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 Hi, I completely agree with you. I think lots of people use snapshots for backup purposes and these ones shouldn't be writable. Bye, David Arendt