On Fri, 2007-06-15 at 14:19 -0700, David Miller wrote: > From: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> > Date: Fri, 15 Jun 2007 17:15:45 +0100 > > > > > Any particular reason why this is done as a separate block device driver > > > > rather than as SCSI? > > > > > > Because no new fake SCSI drivers are accepted anymore. > > > > Where did drivers/ata come from ;) > > > > How about making it a fake ata driver if James is being fussy 8) > > That sounds like a good idea for my virtual I/O case on > Niagara too actually :-) I have no objections to VIO servers speaking SCSI ... if you want to do that, I suggest you look at an existing example, like drivers/scsi/ibmvscsi (the actual communication piece is very ppc hypervisor specific, though). However, I do strongly believe that using SCSI for devices which truly aren't SCSI (i.e. you have to code a shim in the driver between the SCSI commands and whatever your device speaks) is wrong ... if SCSI has features that the generic block layer doesn't, then we need to move the function from SCSI to block to give you access ... in theory this was the rationale for having libata as the last "fake" SCSI driver, so we could identify this functionality and begin to move it. > Another quirk I have to deal with is that under LDOMs you > can export full disks and also just slices. So I'll have > to get down into the partition machinery to support that > somehow. For this, it sounds like you might find nbd a more enticing proposition ... it already is partition independent and is basically a block to net socket exporter. James - 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
