Subject: Re: pmap questions
To: None <>
From: Wolfgang Solfrank <>
List: tech-kern
Date: 06/09/1994 12:41:25
> What I'm wondering is 
> basically why the routines that are used in startup of the pmap module, ie;
> - pmap_free_pages
> - pmap_virtual_space
> - pmap_next_page
> have been eliminated in the NetBSD code and (apparently) have been substituted
> for the kernel freely manipulating the global variables(sigh) avail_start and
> virtual_avail.

I'm not sure what you are referring here to.

The current vm code in NetBSD has two rather different solutions to the

One, stemming from the Net2 tape, has an interface that is (apparently?)
based on MACH 2.x (not really sure here) code. This interface didn't allow
for noncontiguous physical memory.

So I decided to port the MACH 3 startup code to NetBSD to work around the
hole in the i386 address space. Additionally I found the code a bit clearer
than the old code. This code does use the pmap routines you mentioned above
and doesn't manipulate global variables directly (at least not in the
machine independent code).

If you have any specific questions, feel free to ask.
ws@TooLs.DE     (Wolfgang Solfrank, TooLs GmbH) +49-228-985800