On Fri, Oct 04, 2024 at 02:07:05PM +0100, John Garry wrote: > Sure, that is true (about being able to atomically write 1x FS block if the > bdev support it). > > But if we are going to add forcealign or similar later, then it would make > sense (to me) to have FS_XFLAG_ATOMICWRITES (and its other flags) from the > beginning. I mean, for example, if FS_XFLAG_FORCEALIGN were enabled and we > want atomic writes, setting FS_XFLAG_ATOMICWRITES would be rejected if AG > count is not aligned with extsize, or extsize is not a power-of-2, or > extsize exceeds bdev limits. So FS_XFLAG_ATOMICWRITES could have some value > there. > > As such, it makes sense to have a consistent user experience and require > FS_XFLAG_ATOMICWRITES from the beginning. Well, even with forcealign we're not going to lose support for atomic writes <= block size, are we?