Re: [PATCH 3/3][RFC](Repost) ext4: add a message in remount/umount for ext4

[Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>]

Hi Ted, thank you for your comment.

Theodore Tso wrote:
 > On Wed, Sep 30, 2009 at 03:49:31PM +0900, Toshiyuki Okajima wrote:
 > > > From: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
 > > >
 > > > ext4 doesn't log a record of having unmounted the filesystem. And ext4 doesn't
 > > > log a record when the filesystem is remounted also with read-only. Therefore
 > > > in the system log, we cannot judge whether or not at the certain time this
 > > > filesystem user touches it.
 > > > For enterprise users, they often want to know when a certain filesystem is
 > > > mounted/remounted/unmounted.
 > > >
 > > > So, we output the message to the system log when the filesystem is
 > > > remounted/unmounted.
 > > >
 > > > Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
 >
 > The question of whether this should be at the VFS layer is still an
 > open one, I think.  It is true that ext3 and ext4 does print some
I am recognizing it. But I think I have already explained its answer as follows:
  - A print mechanism has already been included at mount time.
  - The umount operation is opposite "mount operation". Therefore I think
    it is no problem that we add the print mechanism at the umount time.

 > filesystem specific information, but that could be handled via a new
 > method function in struct super_ops:
 >
 >        mount_msg(struct super *sb, char *buf, int buflen)
 >
However, I have noticed that the purpose of ext3/ext4 messages at mount time
is for specific information but not for a general purpose by this comment.

So, I think I should rearrange this feature into the VFS layer.
I try to reimplement it later.

Thanks,
Toshiyuki Okajima