Subject: Re: Building an alternate backing store.
To: gabriel rosenkoetter <firstname.lastname@example.org>
From: Allen Briggs <email@example.com>
Date: 07/13/2000 17:56:00
> Ahem. Yes, I do mean pmap_entER().
pmap_enter() is responsible for entering and changing KVA and physical
memory address mappings. I think it's in the p.178 - 180 range of the
4.4BSD book (I was just looking at this last weekend).
> This led me to uvm_fault.c, and from there to pmap_enter(), since
> that's how uvm_fault(), the main entry point for any page fault, goes
> about getting memory pages back where they belong from wherever
> they've gone.
pmap_enter() is just used to enter the page mapping--it doesn't
actually acquire the data from wherever it's been. If you look
around in uvm_fault(), I think you'll find that the pager (through
uobj->pgops) is responsible.