Received-SPF: pass (google.com: best guess record for domain of linux-ext4-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Wed, 1 Apr 2020 08:18:37 -0700
From:   "Darrick J. Wong" <darrick.wong@oracle.com>
To:     David Howells <dhowells@redhat.com>
Cc:     tytso@mit.edu, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org
Subject: Re: Exporting ext4-specific information through fsinfo attributes
Message-ID: <20200401151837.GB56931@magnolia>
References: <2461554.1585726747@warthog.procyon.org.uk>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <2461554.1585726747@warthog.procyon.org.uk>
User-Agent: Mutt/1.9.4 (2018-02-28)
Sender: linux-ext4-owner@vger.kernel.org
Precedence: bulk

On Wed, Apr 01, 2020 at 08:39:07AM +0100, David Howells wrote:
> Hi Ted,
> 
> Whilst we were at Vault, I asked you if there was any live ext4 information
> that it could be useful to export through fsinfo().  I've implemented a patch
> that exports six superblock timestamps:
> 
> 	FSINFO_ATTR_EXT4_TIMESTAMPS: 
> 		mkfs    : 2016-02-26 00:37:03
> 		mount   : 2020-03-31 21:57:30
> 		write   : 2020-03-31 21:57:28
> 		fsck    : 2018-12-17 23:32:45
> 		1st-err : -
> 		last-err: -
> 
> but is there anything else that could be of interest?

The entire superblock as a binary blob? :)

This way we can begin moving dumpe2fs/tune2fs away from reading the raw
disk on live filesystems.

(I'd make the same noises about xfs, but less urgently since we already
have ioctls for that purpose.)

--D

> 
> Thanks,
> David
>