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Re: [MiNT] virtual address spaces



Frank Naumann napisał(a):
Hello!

1. Disk drivers

Atm. disk drivers (XHDI) live outside the kernel. That means the are hard to be put into virtual address space.


That's why the kernel overwrite the XHDI handler by a system call wrapper. XHDI calls from user space applications are redirected to a system call and handled inside the kernel (privilege checking, restricted to root). So XHDI is no problem.

Ok, but still, driver lives outside kernel and is not even a process...

3. Apps that have idea how memory looks, GEM protocols and pointer sharing....

This must be global memory like at the moment with memory protection enabled. Can be done as shared address space between all applications.

As I previously written about we need to separate our virtual machine into 2 worlds.

I don't think we need two worlds. I think the existing mechanism are sufficient. Legacy programs can be set to use global memory as it's already the case for memory protection.

The main problem are other things, all applications that use Super() for example, or Supexec(), Setexc() and so on, then XBIOS calls for sound and so on.

I do not understand. Do you want all processes to live in one memory space?

With Xbios, I understand the problem is that ew do not have all of it implememnted? We coul borrow some code from EmuTOS then.

--
Semper Fidelis

Adam Klobukowski
atari@gabo.pl