Module os::loader

Loading user applications into memory

For chapter 3, user applications are simply part of the data included in the kernel binary, so we only need to copy them to the space allocated for each app to load them. We also allocate fixed spaces for each task’s KernelStack and UserStack.

Structs

KernelStack

kernel stack structure

UserStack

user stack structure

Statics

KERNEL_STACK

kernel stack instance

USER_STACK

user stack instance

Functions

get_base_i

Get base address of app i.

get_num_app

Get the total number of applications.

init_app_cx

get app info with entry and sp and save TrapContext in kernel stack

load_apps

Load nth user app at [APP_BASE_ADDRESS + n * APP_SIZE_LIMIT, APP_BASE_ADDRESS + (n+1) * APP_SIZE_LIMIT).