On Thu, Jun 19, 2014 at 11:05:59AM -0700, James Bottomley wrote: > That's not really a good idea either ... I did think of it. We'll end > up with a cmd_type of REQ_TYPE_FS which because of REQ_FLUSH (or REQ_FUA > or REQ_DISCARD or any number of other things) we have to treat as though > it were REQ_TYPE_BLOCK_PC. It's much better to tune handling > expectations according to req->cmd_type because that's what we already > do. These commands are actually set up by our handlers, so it's up to > us to mark the request type correctly. Looking at the places where the SCSI midlayer cares about the request type: - scsi_finish_command to call ->done for non-PC requests. Given that we called into the driver to setup flush/discard/etc we should also call into the driver on request completion - scsi_eh_action: ditto for error handling - scsi_noretry_cmd: I don't see why we'd want to treat flush request as having an implicit failfast flag - scsi_io_completion: this mostly opts out of all kinds of error handling and retries, not really what we'd want either - scsi_unprep_fn: calls ->uninit_command only for !PC request, so your patch introduces a leak for discard requests -- 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
