On Thu, Nov 17, 2011 at 10:58:53AM +1100, Dave Chinner wrote: > However, I'm not sure this is even relevant - if we've got multiple > extents to write to and then convert in a single high level IO, they > would have been mapped into separate IOs, bios and ioends. That's > definitely the case for buffered IO, and AFAICT, the same for direct > IO (Christoph - can you confirm this?). For direct I/O we do a single call to xfs_iomap_write_unwritten for the whole write system call, which might span multiple extents. > Chrisptoph, if this "only one extent per ioend" condition is really > true, then is there any need for this loop at all? i.e. do we ever > do a partial extent conversion for a completed IO and therefore have > to do a second transaction to convert the rest of the extent? It might be a good idea to move the looping code directly into the direct I/O completion path. Or replace the current direct I/O end_io handler mess with something that actually makes sense. For now I'd leave the code as-is but with the fix pointed out by Ben, and look into a test case reproducing that bug. I'll look into figuring out something saner for the direct I/O case later. _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
