DragonFly- master lib/libstand hammerread.c sys/boot/common boot2.h dinode.h ufsread.c sys/boot/pc32/boot2 Makefile boot1.S boot2.c sys/boot/pc32 bootasm.h sys/sys types.h

Matthew Dillon dillon at apollo.backplane.com
Mon Mar 2 10:58:47 PST 2009

:If legacy boot2 couldn't grow beyond 8K, (or 16K) neither a 32K nor 64K 
:wrap would have mattered?
:And one can put a reasonably useful 16-bit Virtual Machine OS, Virtual 
:Memory System, with disk I/O and an editor into 8K. Even on an 8-bit 
:CPU.  Forth and ASM didn't go away.  They just hide really well....

    The 32 bit disklabel only has 8K of space reserved to hold boot2.

    The 64 bit disklabel has 32K of space reserved to hold boot2.

    The boot1 code prior to this fix could only load up to an 8K boot2
    due to segment wrapping.

    The boot1 code after this fix can now load up to a 16K boot2 before
    it hits the segment wrapping problem.

    Adjusting boot1 to be able to load an even larger boot2 would
    require a lot more messing around then I want to do.

					Matthew Dillon 
					<dillon at backplane.com>

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