Part of the problem may be that we have already done much of what you're
trying to do.  In this case,

	lfs_blktodb converts between bsize and d_secsize;
	lfs_fbshift converts between bsize and fsize;
	lfs_fsbtodb converts between fsb and d_secsize.

"fsb" is the unit that ufs_daddr_ts count; in v1 it is sectors, in v2
it is fragments; so on LFSv2 filesystems it doesn't do anything but on v1
it does.

newfs_lfs already looks at d_secsize from the disklabel to set up its
parameters; I think the only thing you'll need to change is the definition
of i_ffs_blocks...and then test, of course :^)

						Konrad Schroder
						perseant@hhhh.org