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Re: blocksizes (Izumi Tsutsui) writes:

>Disklabel in cd(4) requires hardware block size for partition offsets,

All disklabels use hardware block sizes. cd(4) is no exception.

>but it also uses DEV_BSIZE for sizes.

cd(4) uses DEV_BSIZE units to address blocks.

>Isn't it one example of inconsistent hacks?

No, this is a place where this is used consistently. Maybe
it becomes clear when treating the disk address not like
a way to access hardware but a way to specify the data
While these are related, it is not a 1:1 relationship.

>There is no "right" solution. We can fix the hack with hacks,
>or we can also redesign it. Someone[tm] should make a decision.
>That's all.

Yesterdays' redesign is todays' hacks. By chosing words you
already say what you consider a "wrong" solution.

So far I have heard about three models.

- use DEV_BSIZE addressing (that's what we have now, no changes)
- use byte addressing (almost the same, just a few bits more, requires
  minor changes to device drivers and other code).
- use native block addressing (what we left in 1994, requires significant
  changes to device drivers and minor changes to other code).

To me, none of this has significant advantages.

                                Michael van Elst
                                "A potential Snark may lurk in every tree."

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