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Merge pull request #703 from phil-opp/post-09-fix

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Update frame allocation code to x86_64 0.8.1
This commit is contained in:
Philipp Oppermann
2019-12-11 16:37:49 +01:00
committed by GitHub
parent 6c1594ea24 c7bc26d8ee
commit f392d8a7f5
1 changed files with 10 additions and 5 deletions
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15
src/memory.rs
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@@ -2,6 +2,7 @@ use bootloader::bootinfo::{MemoryMap, MemoryRegionType};
use x86_64::{
structures::paging::{
FrameAllocator, Mapper, OffsetPageTable, Page, PageTable, PhysFrame, Size4KiB,
UnusedPhysFrame,
},
PhysAddr, VirtAddr,
};
@@ -44,9 +45,11 @@ pub fn create_example_mapping(
use x86_64::structures::paging::PageTableFlags as Flags;
let frame = PhysFrame::containing_address(PhysAddr::new(0xb8000));
// FIXME: ONLY FOR TEMPORARY TESTING
let unused_frame = unsafe { UnusedPhysFrame::new(frame) };
let flags = Flags::PRESENT | Flags::WRITABLE;
let map_to_result = unsafe { mapper.map_to(page, frame, flags, frame_allocator) };
let map_to_result = mapper.map_to(page, unused_frame, flags, frame_allocator);
map_to_result.expect("map_to failed").flush();
}
@@ -54,7 +57,7 @@ pub fn create_example_mapping(
pub struct EmptyFrameAllocator;
unsafe impl FrameAllocator<Size4KiB> for EmptyFrameAllocator {
fn allocate_frame(&mut self) -> Option<PhysFrame> {
fn allocate_frame(&mut self) -> Option<UnusedPhysFrame> {
None
}
}
@@ -79,7 +82,7 @@ impl BootInfoFrameAllocator {
}
/// Returns an iterator over the usable frames specified in the memory map.
fn usable_frames(&self) -> impl Iterator<Item = PhysFrame> {
fn usable_frames(&self) -> impl Iterator<Item = UnusedPhysFrame> {
// get usable regions from memory map
let regions = self.memory_map.iter();
let usable_regions = regions.filter(|r| r.region_type == MemoryRegionType::Usable);
@@ -88,12 +91,14 @@ impl BootInfoFrameAllocator {
// transform to an iterator of frame start addresses
let frame_addresses = addr_ranges.flat_map(|r| r.step_by(4096));
// create `PhysFrame` types from the start addresses
frame_addresses.map(|addr| PhysFrame::containing_address(PhysAddr::new(addr)))
let frames = frame_addresses.map(|addr| PhysFrame::containing_address(PhysAddr::new(addr)));
// we know that the frames are really unused
frames.map(|f| unsafe { UnusedPhysFrame::new(f) })
}
}
unsafe impl FrameAllocator<Size4KiB> for BootInfoFrameAllocator {
fn allocate_frame(&mut self) -> Option<PhysFrame> {
fn allocate_frame(&mut self) -> Option<UnusedPhysFrame> {
let frame = self.usable_frames().nth(self.next);
self.next += 1;
frame