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feat(paging): switch page table and identity map VGA buffer and multiboot info structs
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Signed-off-by: Julien CLEMENT <julien.clement@epita.fr>
This commit is contained in:
Julien CLEMENT 2021-12-08 02:59:24 +01:00
parent fcf2f7f439
commit 5e994b9dff
1 changed files with 27 additions and 3 deletions
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30
src/memory/paging/mod.rs
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@ -43,8 +43,22 @@ pub fn kernel_remap<A>(allocator: &mut A, boot_info: &BootInformation)
}
}
}
let vga_buffer_frame = Frame::<Size4KiB>::containing_address(PhysAddr::new(0xb8000));
unsafe {
mapper.identity_map(vga_buffer_frame, Flags::PRESENT | Flags::WRITABLE, allocator).expect("Failed to identity map VGA buffer").flush();
}
let multiboot_start = Frame::<Size4KiB>::containing_address(PhysAddr::new(boot_info.start_address() as u64));
let multiboot_end = Frame::containing_address(PhysAddr::new(boot_info.end_address() as u64 - 1));
for frame in Frame::range_inclusive(multiboot_start, multiboot_end) {
unsafe {
mapper.identity_map(frame, Flags::PRESENT, allocator).expect("Failed to identity map multiboot info struct").flush();
}
}
});
new_table.activate();
println!("Loaded new page table!");
}
struct InactivePageTable {
@ -79,6 +93,18 @@ impl InactivePageTable {
temporary_page.unmap(active_table);
}
pub fn activate(&mut self) -> InactivePageTable {
let old_table = InactivePageTable {
p4_frame: Frame::containing_address(
control::Cr3::read().0.start_address()
),
};
unsafe {
control::Cr3::write(self.p4_frame, control::Cr3Flags::empty());
}
old_table
}
}
pub fn get_active_page_table() -> RecursivePageTable<'static> {
@ -104,8 +130,6 @@ pub fn test_paging<A>(allocator: &mut A)
let frame_ptr: *mut u8 = frame.start_address().as_u64() as *mut u8;
unsafe {
println!("Page: {:#?}, Frame: {:#?}", *page_ptr, *frame_ptr);
*frame_ptr = 42;
println!("Page: {:#?}, Frame: {:#?}", *page_ptr, *frame_ptr);
println!("Page: {:#?}, Frame: {:#?}", page_ptr, frame_ptr);
}
}