d93ed09564
* Changed IS_USER_ADDRESS to check an address using USER_BASE and USER_SIZE, rather than just !IS_KERNEL_ADDRESS. The old check would allow user buffers to point into the physical memory map area. * Added an unmapped hole at the end of the bottom half of the address space which catches buffers that cross into the uncanonical address region. This also removes the need to check for uncanonical return addresses in the syscall handler, it is no longer possible for the return address to be uncanonical under normal circumstances. All cases in which the return address might be changed by the kernel are still handled via the IRET path.
33 lines
1.2 KiB
C
33 lines
1.2 KiB
C
/*
|
|
** Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
|
|
** Distributed under the terms of the NewOS License.
|
|
*/
|
|
#ifndef _KERNEL_ARCH_PPC_KERNEL_H
|
|
#define _KERNEL_ARCH_PPC_KERNEL_H
|
|
|
|
#include <arch/cpu.h>
|
|
|
|
// memory layout
|
|
#define KERNEL_BASE 0x80000000
|
|
#define KERNEL_SIZE 0x80000000
|
|
#define KERNEL_TOP (KERNEL_BASE + (KERNEL_SIZE - 1))
|
|
|
|
/*
|
|
** User space layout is a little special:
|
|
** The user space does not completely cover the space not covered by the kernel.
|
|
** This is accomplished by starting user space at 1Mb and running to 64kb short of kernel space.
|
|
** The lower 1Mb reserved spot makes it easy to find null pointer references and guarantees a
|
|
** region wont be placed there. The 64kb region assures a user space thread cannot pass
|
|
** a buffer into the kernel as part of a syscall that would cross into kernel space.
|
|
*/
|
|
#define USER_BASE 0x100000
|
|
#define USER_BASE_ANY USER_BASE
|
|
#define USER_SIZE (0x80000000 - (0x10000 + 0x100000))
|
|
#define USER_TOP (USER_BASE + (USER_SIZE - 1))
|
|
|
|
#define KERNEL_USER_DATA_BASE 0x6fff0000
|
|
#define USER_STACK_REGION 0x70000000
|
|
#define USER_STACK_REGION_SIZE ((USER_TOP - USER_STACK_REGION) + 1)
|
|
|
|
#endif /* _KERNEL_ARCH_PPC_KERNEL_H */
|