83 lines
2.2 KiB
Rust
83 lines
2.2 KiB
Rust
use crate::trap::TrapContext;
|
|
use crate::config::*;
|
|
|
|
#[repr(align(4096))]
|
|
#[derive(Copy, Clone)]
|
|
struct KernelStack {
|
|
data: [u8; KERNEL_STACK_SIZE],
|
|
}
|
|
|
|
#[repr(align(4096))]
|
|
#[derive(Copy, Clone)]
|
|
struct UserStack {
|
|
data: [u8; USER_STACK_SIZE],
|
|
}
|
|
|
|
static KERNEL_STACK: [KernelStack; MAX_APP_NUM] = [
|
|
KernelStack { data: [0; KERNEL_STACK_SIZE], };
|
|
MAX_APP_NUM
|
|
];
|
|
|
|
static USER_STACK: [UserStack; MAX_APP_NUM] = [
|
|
UserStack { data: [0; USER_STACK_SIZE], };
|
|
MAX_APP_NUM
|
|
];
|
|
|
|
impl KernelStack {
|
|
fn get_sp(&self) -> usize {
|
|
self.data.as_ptr() as usize + KERNEL_STACK_SIZE
|
|
}
|
|
pub fn push_context(&self, trap_cx: TrapContext) -> usize {
|
|
let trap_cx_ptr = (self.get_sp() - core::mem::size_of::<TrapContext>()) as *mut TrapContext;
|
|
unsafe { *trap_cx_ptr = trap_cx; }
|
|
trap_cx_ptr as usize
|
|
}
|
|
}
|
|
|
|
impl UserStack {
|
|
fn get_sp(&self) -> usize {
|
|
self.data.as_ptr() as usize + USER_STACK_SIZE
|
|
}
|
|
}
|
|
|
|
fn get_base_i(app_id: usize) -> usize {
|
|
APP_BASE_ADDRESS + app_id * APP_SIZE_LIMIT
|
|
}
|
|
|
|
pub fn get_num_app() -> usize {
|
|
extern "C" { fn _num_app(); }
|
|
unsafe { (_num_app as usize as *const usize).read_volatile() }
|
|
}
|
|
|
|
pub fn load_apps() {
|
|
extern "C" { fn _num_app(); }
|
|
let num_app_ptr = _num_app as usize as *const usize;
|
|
let num_app = get_num_app();
|
|
let app_start = unsafe {
|
|
core::slice::from_raw_parts(num_app_ptr.add(1), num_app + 1)
|
|
};
|
|
// clear i-cache first
|
|
unsafe { asm!("fence.i"); }
|
|
// load apps
|
|
for i in 0..num_app {
|
|
let base_i = get_base_i(i);
|
|
// clear region
|
|
(base_i..base_i + APP_SIZE_LIMIT).for_each(|addr| unsafe {
|
|
(addr as *mut u8).write_volatile(0)
|
|
});
|
|
// load app from data section to memory
|
|
let src = unsafe {
|
|
core::slice::from_raw_parts(app_start[i] as *const u8, app_start[i + 1] - app_start[i])
|
|
};
|
|
let dst = unsafe {
|
|
core::slice::from_raw_parts_mut(base_i as *mut u8, src.len())
|
|
};
|
|
dst.copy_from_slice(src);
|
|
}
|
|
}
|
|
|
|
pub fn init_app_cx(app_id: usize) -> usize {
|
|
KERNEL_STACK[app_id].push_context(
|
|
TrapContext::app_init_context(get_base_i(app_id), USER_STACK[app_id].get_sp()),
|
|
)
|
|
}
|