Re: kern/42573: DIRBLKSIZ in <ufs/ufs/dir.h> should not beDEV_BSIZE constant

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

>  My thoughts are the DEV_BSIZE should remain forever as 512
>  (cygwin fubar not withstanding).

Probably we need to have some macro which represent
"traditional sector size (which is 512)",
but I don't think we should keep it as DEV_BSIZE.

Anyway we can't use DEV_BSIZE in src/tools as mentioned in
PR toolchain/42555 and toolchain/42574.

>  But to make everything fit (eg i386 boot code) the byte alignments
>  cannot change - the label has to remain in bytes 512-1203.

Does it? What about "LABELSECTOR" in <machine/disklabel.h>?
Shouldn't sys/arch/i386/stand/mbr/mbr.S be sector size aware?

>  (I have a USB memory stick with 2k sectors, the 0x55, 0xaa are in
>  bytes 510 and 511 as usual.)

Magic should be at MBR_MAGIC_OFFSET defined in <sys/bootblock.h>
so it doesn't matter of sector size, does it?

Anyway, these are different topic from this PR.
---
Izumi Tsutsui