On Wed, Jul 07, 2010 at 12:45:25AM +0100, David Howells wrote: > Dave Chinner <david@xxxxxxxxxxxxx> wrote: > > > I'd prefer generic flags are not dependent on fixed values from a > > specific filesystem several layers down the storage stack. > > They're not so dependent. History says otherwise. :) > They're based on the FS_IOC_[GS]ETFLAGS ioctl which > even XFS translates its flags for. Sure, because the ioctl flags values are derived from the ext2 on-disk format flags and hence don't match anything XFS related at all. > These ioctl flags must now remain > invariant. Whilst they might have originated as Ext2/3/4 flags, they're now > independent of that. Yes, the ioctl flags must remain invariant. OTOH, the generic inode flags (S_*) have no such invariant requirement and have a history of frequent change. IMO, that means some flags should not be tied to the value of a specific subsystem just so a subsystem specific optimisation can be made. It just seems like a dangerous layering violation to be making... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
