On Mon, 21 Nov 2011, Christoph Hellwig wrote: > On Sun, Nov 20, 2011 at 01:39:12PM -0800, Hugh Dickins wrote: > > > But since the present situation is that tmpfs has one interface to > > punching holes, madvise(MADV_REMOVE), that IBM were pushing 5 years ago; > > but ext4 (and others) now a fallocate(FALLOC_FL_PUNCH_HOLE) interface > > which IBM have been pushing this year: we do want to normalize that > > situation and make them all behave the same way. > > FALLOC_FL_PUNCH_HOLE was added by Josef Bacik, who happens to work for > Red Hat, but I doubt he was pushing any corporate agenda there, he was > mostly making btrfs catch up with the 15 year old XFS hole punching > ioctl. Yeah, my apologies to Josef and to IBM and to XFS for my regrettable little outburst of snarkiness :( > > > > And if tmpfs is going to support fallocate(FALLOC_FL_PUNCH_HOLE), > > looking at Amerigo's much more attractive V2 patch, it would seem > > to me perverse to permit the deallocation but fail the allocation. > > Agreed. Thanks a lot for useful info, and saving me looking up the ENOSPC issue. Hugh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>