On Fri, Mar 11, 2022 at 12:51:35PM -0800, Keith Busch wrote: > On Fri, Mar 11, 2022 at 12:19:38PM -0800, Luis Chamberlain wrote: > > NAND has no PO2 requirement. The emulation effort was only done to help > > add support for !PO2 devices because there is no alternative. If we > > however are ready instead to go down the avenue of removing those > > restrictions well let's go there then instead. If that's not even > > something we are willing to consider I'd really like folks who stand > > behind the PO2 requirement to stick their necks out and clearly say that > > their hw/fw teams are happy to deal with this requirement forever on ZNS. > > Regardless of the merits of the current OS requirement, it's a trivial > matter for firmware to round up their reported zone size to the next > power of 2. This does not create a significant burden on their part, as > far as I know. I can't comment on FW burdens but adding po2 zone size creates holes for the FW to deal with as well. > > And po2 does not even seem to be the real problem here. The holes seem > to be what's causing a concern, which you have even without po2 zones. > I'm starting to like the previous idea of creating an unholey > device-mapper for such users... I see holes as being caused by having to make zone size po2 when capacity is not po2. po2 should be tied to the holes, unless I am missing something. BTW if we go down the dm route can we start calling it dm-unholy.
