On Fri, May 11, 2007 at 04:33:01PM +0530, Suparna Bhattacharya wrote:

On Fri, May 11, 2007 at 08:39:50AM +1000, David Chinner wrote:

quoted

All I'm really interested in right now is that the fallocate
_interface_ can be used as a *complete replacement* for the
pre-existing XFS-specific ioctls that are already used by
applications.  What ext4 can or can't do right now is irrelevant to
this discussion - the interface definition needs to take priority
over implementation....

Would you like to write up an interface definition description (likely
man page) and post it for review, possibly with a mention of apps using
it today ?

Yeah, I started doing that yesterday as i figured it was the only way
to cut the discussion short....

One reason for introducing the mode parameter was to allow the interface to
evolve incrementally as more options / semantic questions are proposed, so
that we don't have to make all the decisions right now. 
So it would be good to start with a *minimal* definition, even just one mode.
The rest could follow as subsequent patches, each being reviewed and debated
separately. Otherwise this discussion can drag on for a long time.

Minimal definition to replace what applicaitons use on XFS and to
support poasix_fallocate are the thre that have been mentioned so
far (FA_ALLOCATE, FA_PREALLOCATE, FA_DEALLOCATE). I'll document them
all in a man page...

Cheers,

Dave.
-- 
Dave Chinner
Principal Engineer
SGI Australian Software Group