On Fri, Jun 01, 2007 at 03:59:51PM +1000, Neil Brown wrote: > On Friday June 1, dgc@xxxxxxx wrote: > > On Thu, May 31, 2007 at 02:31:21PM -0400, Phillip Susi wrote: > > > David Chinner wrote: > > > >That sounds like a good idea - we can leave the existing > > > >WRITE_BARRIER behaviour unchanged and introduce a new WRITE_ORDERED > > > >behaviour that only guarantees ordering. The filesystem can then > > > >choose which to use where appropriate.... > > > > > > So what if you want a synchronous write, but DON'T care about the order? > > > > submit_bio(WRITE_SYNC, bio); > > > > Already there, already used by XFS, JFS and direct I/O. > > Are you sure? > > You seem to be saying that WRITE_SYNC causes the write to be safe on > media before the request returns. Sorry, I wasn't really all that clear :/ What I'm saying the *interface* for higher layer to tell the block layers that a sync write is being executed is already there. i.e. we can already tell the block layer that we are doing a synchronous I/O. Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel