Re: [PATCH 1/5] vfs: vfs-level fiemap interface

[Josef Bacik <jbacik@redhat.com>]

On Wed, May 28, 2008 at 01:12:40PM -0700, Mark Fasheh wrote:
> On Wed, May 28, 2008 at 03:54:29PM -0400, Josef Bacik wrote:
> > > > Btw, how many block-based file systems that don't return multiple blocks via
> > > > get_blocks() are there that we actually care about enough to write this
> > > > code?
> > > 
> > > That I have no clue about.  Joseph?
> > > 
> > >
> > 
> > Well I can't comment on the "care enough about" part, but looking at it I don't
> > think reiserfs does, it just maps the one block we ask for.  Just cursory
> > looking through stuff it looks like most other stuff does map as much as it can,
> > even FAT does.  Thanks much,
> 
> Josef, thanks for looking.
> 
> Isn't reiserfs extent based anyway? So really, it should (eventually) get a
> real ->fiemap callback.
> 	--Mark
>

I looked again and then double checked with Chris and reiserfs (v3 at least) is
block based.  I can look through all the other block based fs's if you like and
see if any others do this, but like I said I hit all the ones that I could think
of that are commonly used and reiser was the only one that doesn't map multiple
blocks at once.  Thanks much,

Josef