creation time stamps for ext4 ?

[Andreas Dilger]

On Oct 05, 2006  12:55 -0400, Theodore Tso wrote:
> > I've given this some thought for adding creation time as part of the nsec
> > timestamp patch.  That is more feasable if we move the nsec ctime into
> > the main inode to double as the version field.
> 
> Shoehorning an extra creation time field into the inode is relatively
> easy, but it's also necessary to have system calls to get and set the
> creation time.  The stat structure doesn't have room for the creation
> time, so that means a new version of the stat structure exported the
> kernel, and a new version of the stat structure exported by glibc.

For Lustre and NFSv4, an in-kernel interface is sufficient.

I was thinking that as a preliminary userspace interface we can use
getxattr with a standard name like user.crtime.  Storing the crtime
directly in the inode is more efficient than a separate EA, but it would
also be compatible if Samba wanted to use real EAs to store this in the
absence of large inodes.

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.