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Ok, here I am, I am now ready to start on paging, I can setup a basic PMode environment. Now I need to setup paging.

Ok, I understand that the page directory holds 1024 32bit page table descriptors (dont know if they are called descriptors, but that sounds good enough), and a page table holds 1024 32bit page descriptors, to map the entire 4GB it takes 4MB of memory, 4KB for the directory, and 4KB for each of the 1024 tables. Now I know nothing, I know about the directory address going into cr3, but how does it work from here?

How do I reference a memory location?

I have seen the docs from the popular reference sites, but I would like some kind of clear example code, if anyone has some that they are willing to part with. lol

Thanks.

In paged mode, each 4k of memory addresses can virtually map any 4K physical page frame in memory. Here's the design i've used personnally for my own OS.

[table][tr]
[td]0..4M[/td][td]microkernel[/td][td]maps 0..4M physical addresses: convenient for initialization & drivers (you're sure contiguous addresses means contiguous physical locations). All processes map this place identically, thus it is shared among everything[/td][/tr]
[tr][td]4M..4G-8M[/td][td]private[/td][td] free mapping, depending on the running process. These pages are usually allocated on demand (first access to a page will select a free frame and give it to the process for that page)[/td][/tr]
[tr][td]4G-8M..4G-4M[/td][td]directory[/td][td] the 1022th entry of the page directory refers to the directory itself, thus you can easily access to any page table of the current process by using directory[address>>12].[/td][/tr]
[tr][td]4G-4M..4G[/td][td]page frame viewer[/td][td] this is a special shared system place where a process in kernel mode can map any physical page frame it wants. I also use it to keep a map of pages references count (for copy-on-write implementation)[/td]
[/tr]
[/table]