blob: cec17c991231dd709c09583c071d9fedb9ca81c8 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
|
pub struct Mem;
pub struct VAddr(u64);
impl Mem {
// units
pub const K: usize = 1024;
pub const M: usize = 1024 * Mem::K;
pub const G: usize = 1024 * Mem::M;
// physical memory layout: qemu defaults to 128 MiB phy Memory
pub const PHY_TOP: usize = 128 * Mem::M;
// 4 lv 4K paging
pub const PAGE_SIZE: usize = 0x1000;
pub const PAGE_SHIFT: usize = 12;
pub const PAGE_MASK: u64 = 0xfff;
pub const L0_SHIFT: u8 = 39;
pub const L0_MASK: u64 = 0x1ff << Mem::L0_SHIFT;
pub const L1_SHIFT: u8 = 30;
pub const L1_MASK: u64 = 0x1ff << Mem::L1_SHIFT;
pub const L2_SHIFT: u8 = 21;
pub const L2_MASK: u64 = 0x1ff << Mem::L2_SHIFT;
pub const L3_SHIFT: u8 = 12;
pub const L3_MASK: u64 = 0x1ff << Mem::L3_SHIFT;
pub const PHY_PAGES: usize = Mem::PHY_TOP >> Mem::PAGE_SHIFT;
// size of frame allocator bitmap: number of physical frames / 8 for 128M
// memory (37268) 4k pages, 37268 bits are needed, hence
// 4096 bytes, exactly one page!
pub const PHY_BM_SIZE: usize = Mem::PHY_PAGES >> 3;
}
impl VAddr {
pub fn roundup_4k(&self) {
todo!()
}
pub fn rounddown_4k(&self) {
todo!()
}
pub fn page_number(&self) -> u64 {
self.0 >> Mem::PAGE_SHIFT
}
}
// PHY_TOP 128M
// ~ free frames
// PMA::bitmap + PHY_BM_SIZE
// ~ ___KERNEL_END__
// KERNEL IMAGE
// KERNEL START 1 M
|
