On 08/08/2010 04:31 PM, Christoph Hellwig wrote: > On Sat, Aug 07, 2010 at 12:13:06PM +0200, Tejun Heo wrote: >> The patch was on top of v2.6.35 but was generated against dirty tree >> and wouldn't apply cleanly. Here's the proper one. > > Here's an updated version: > > (a) ported to Jens' current block tree > (b) optimize barriers on devices not requiring flushes to be no-ops > (b) redo the blk_queue_ordered interface to just set QUEUE_HAS_FLUSH > and QUEUE_HAS_FUA flags. Nice. I'm working on a properly split patchset implementing REQ_FLUSH/FUA based interface, which replaces REQ_HARDBARRIER. Empty request w/ REQ_FLUSH just flushes cache but has no other ordering restrictions. REQ_FLUSH + data means preflush + data write. REQ_FUA + data means data would be committed to NV media on completion. REQ_FLUSH + FUA + data means preflush + NV data write. All FLUSH/FUA requests w/ data are ordered only against each other. I think I'll be able to post in several days. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html