Frame Allocator OK.

.gitignore

@@ -2,5 +2,7 @@
 os/target/*
 os/.idea/*
 os/src/link_app.S
+os/Cargo.lock
 user/target/*
-user/.idea/*
+user/.idea/*
+user/Cargo.lock

os/Cargo.lock

@@ -1,148 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-[[package]]
-name = "aho-corasick"
-version = "0.7.15"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7404febffaa47dac81aa44dba71523c9d069b1bdc50a77db41195149e17f68e5"
-dependencies = [
- "memchr",
-]
-
-[[package]]
-name = "bare-metal"
-version = "0.2.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5deb64efa5bd81e31fcd1938615a6d98c82eafcbcd787162b6f63b91d6bac5b3"
-dependencies = [
- "rustc_version",
-]
-
-[[package]]
-name = "bit_field"
-version = "0.10.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
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-
-[[package]]
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-
-[[package]]
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-version = "0.6.0"
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-checksum = "b4e85e760e105b46ae0bd1236578793c6c147ae7463fe95c8350296b8bfcb830"
-dependencies = [
- "spin 0.7.0",
-]
-
-[[package]]
-name = "lazy_static"
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- "spin 0.5.2",
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-
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-
-[[package]]
-name = "os"
-version = "0.1.0"
-dependencies = [
- "buddy_system_allocator",
- "lazy_static",
- "riscv",
-]
-
-[[package]]
-name = "regex"
-version = "1.4.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
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-dependencies = [
- "aho-corasick",
- "memchr",
- "regex-syntax",
- "thread_local",
-]
-
-[[package]]
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-checksum = "3b181ba2dcf07aaccad5448e8ead58db5b742cf85dfe035e2227f137a539a189"
-
-[[package]]
-name = "riscv"
-version = "0.6.0"
-source = "git+https://github.com/rcore-os/riscv#21e32ee1dc786cc0d5006ceee0040ce4f8398575"
-dependencies = [
- "bare-metal",
- "bit_field",
- "bitflags",
- "riscv-target",
-]
-
-[[package]]
-name = "riscv-target"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
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- "lazy_static",
- "regex",
-]
-
-[[package]]
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-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
-dependencies = [
- "semver",
-]
-
-[[package]]
-name = "semver"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
-dependencies = [
- "semver-parser",
-]
-
-[[package]]
-name = "semver-parser"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
-
-[[package]]
-name = "spin"
-version = "0.5.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
-
-[[package]]
-name = "spin"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "652ac3743312871a5fb703f0337e68ffa3cdc28c863efad0b8dc858fa10c991b"
-
-[[package]]
-name = "thread_local"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
-dependencies = [
- "lazy_static",
-]

os/Cargo.toml

@@ -10,6 +10,7 @@ edition = "2018"
 riscv = { git = "https://github.com/rcore-os/riscv", features = ["inline-asm"] }
 lazy_static = { version = "1.4.0", features = ["spin_no_std"] }
 buddy_system_allocator = "0.6"
+spin = "0.7.0"
 
 [features]
 board_qemu = []

os/src/config.rs

@@ -4,6 +4,9 @@ pub const MAX_APP_NUM: usize = 4;
 pub const APP_BASE_ADDRESS: usize = 0x80100000;
 pub const APP_SIZE_LIMIT: usize = 0x20000;
 pub const KERNEL_HEAP_SIZE: usize = 0x30_0000;
+pub const MEMORY_END: usize = 0x80800000;
+pub const PAGE_SIZE: usize = 0x1000;
+pub const PAGE_SIZE_BITS: usize = 0xc;
 
 #[cfg(feature = "board_k210")]
 pub const CPU_FREQ: usize = 10000000;

os/src/main.rs

@@ -37,8 +37,7 @@ fn clear_bss() {
 pub fn rust_main() -> ! {
     clear_bss();
     println!("[kernel] Hello, world!");
-    mm::init_heap();
+    mm::init();
-    mm::heap_test();
     loop {}
     trap::init();
     loader::load_apps();

os/src/mm/address.rs

@@ -0,0 +1,70 @@
+/// T: {PhysAddr, VirtAddr, PhysPageNum, VirtPageNum}
+/// T -> usize: T.0
+/// usize -> T: usize.into()
+use crate::config::{PAGE_SIZE, PAGE_SIZE_BITS};
+
+/// Definitions
+#[derive(Copy, Clone, Debug)]
+pub struct PhysAddr(pub usize);
+
+#[derive(Copy, Clone, Debug)]
+pub struct VirtAddr(pub usize);
+
+#[derive(Copy, Clone, Debug)]
+pub struct PhysPageNum(pub usize);
+
+#[derive(Copy, Clone, Debug)]
+pub struct VirtPageNum(pub usize);
+
+impl From<usize> for PhysAddr {
+    fn from(v: usize) -> Self { Self(v) }
+}
+impl From<usize> for PhysPageNum {
+    fn from(v: usize) -> Self { Self(v) }
+}
+impl From<PhysAddr> for usize {
+    fn from(v: PhysAddr) -> Self { v.0 }
+}
+impl From<PhysPageNum> for usize {
+    fn from(v: PhysPageNum) -> Self { v.0 }
+}
+impl From<usize> for VirtAddr {
+    fn from(v: usize) -> Self { Self(v) }
+}
+impl From<usize> for VirtPageNum {
+    fn from(v: usize) -> Self { Self(v) }
+}
+impl From<VirtAddr> for usize {
+    fn from(v: VirtAddr) -> Self { v.0 }
+}
+impl From<VirtPageNum> for usize {
+    fn from(v: VirtPageNum) -> Self { v.0 }
+}
+impl VirtAddr {
+    pub fn floor(&self) -> VirtPageNum { VirtPageNum(self.0 / PAGE_SIZE) }
+    pub fn ceil(&self) -> VirtPageNum  { VirtPageNum((self.0 + PAGE_SIZE - 1) / PAGE_SIZE) }
+    pub fn page_offset(&self) -> usize { self.0 & (PAGE_SIZE - 1) }
+}
+impl From<VirtAddr> for VirtPageNum {
+    fn from(v: VirtAddr) -> Self {
+        assert_eq!(v.page_offset(), 0);
+        v.floor()
+    }
+}
+impl From<VirtPageNum> for VirtAddr {
+    fn from(v: VirtPageNum) -> Self { Self(v.0 << PAGE_SIZE_BITS) }
+}
+impl PhysAddr {
+    pub fn floor(&self) -> PhysPageNum { PhysPageNum(self.0 / PAGE_SIZE) }
+    pub fn ceil(&self) -> PhysPageNum { PhysPageNum((self.0 + PAGE_SIZE - 1) / PAGE_SIZE) }
+    pub fn page_offset(&self) -> usize { self.0 & (PAGE_SIZE - 1) }
+}
+impl From<PhysAddr> for PhysPageNum {
+    fn from(v: PhysAddr) -> Self {
+        assert_eq!(v.page_offset(), 0);
+        v.floor()
+    }
+}
+impl From<PhysPageNum> for PhysAddr {
+    fn from(v: PhysPageNum) -> Self { Self(v.0 << PAGE_SIZE_BITS) }
+}

os/src/mm/frame_allocator.rs

@@ -0,0 +1,118 @@
+use super::{PhysAddr, PhysPageNum};
+use alloc::vec::Vec;
+use spin::Mutex;
+use crate::config::MEMORY_END;
+use lazy_static::*;
+use core::fmt::{self, Debug, Formatter};
+pub struct FrameTracker(PhysPageNum);
+
+impl Debug for FrameTracker {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        f.write_fmt(format_args!("FrameTracker:PPN={:#x}", self.0.0))
+    }
+}
+
+impl Drop for FrameTracker {
+    fn drop(&mut self) {
+        frame_dealloc(self.0);
+    }
+}
+
+trait FrameAllocator {
+    fn new() -> Self;
+    fn alloc(&mut self) -> Option<PhysPageNum>;
+    fn dealloc(&mut self, ppn: PhysPageNum);
+}
+
+pub struct StackFrameAllocator {
+    current: usize,
+    end: usize,
+    recycled: Vec<usize>,
+}
+
+impl StackFrameAllocator {
+    pub fn init(&mut self, l: PhysPageNum, r: PhysPageNum) {
+        self.current = l.0;
+        self.end = r.0;
+    }
+}
+impl FrameAllocator for StackFrameAllocator {
+    fn new() -> Self {
+        Self {
+            current: 0,
+            end: 0,
+            recycled: Vec::new(),
+        }
+    }
+    fn alloc(&mut self) -> Option<PhysPageNum> {
+        if let Some(ppn) = self.recycled.pop() {
+            Some(ppn.into())
+        } else {
+            if self.current == self.end {
+                None
+            } else {
+                self.current += 1;
+                Some((self.current - 1).into())
+            }
+        }
+    }
+    fn dealloc(&mut self, ppn: PhysPageNum) {
+        let ppn = ppn.0;
+        // validity check
+        if ppn >= self.current || self.recycled
+            .iter()
+            .find(|&v| {*v == ppn})
+            .is_some() {
+            panic!("Frame ppn={:#x} has not been allocated!", ppn);
+        }
+        // recycle
+        self.recycled.push(ppn);
+    }
+}
+
+type FrameAllocatorImpl = StackFrameAllocator;
+
+lazy_static! {
+    pub static ref FRAME_ALLOCATOR: Mutex<FrameAllocatorImpl> =
+        Mutex::new(FrameAllocatorImpl::new());
+}
+
+pub fn init_frame_allocator() {
+    extern "C" {
+        fn ekernel();
+    }
+    FRAME_ALLOCATOR
+        .lock()
+        .init(PhysAddr::from(ekernel as usize).ceil(), PhysAddr::from(MEMORY_END).floor());
+}
+
+pub fn frame_alloc() -> Option<FrameTracker> {
+    FRAME_ALLOCATOR
+        .lock()
+        .alloc()
+        .map(|ppn| FrameTracker(ppn))
+}
+
+fn frame_dealloc(ppn: PhysPageNum) {
+    FRAME_ALLOCATOR
+        .lock()
+        .dealloc(ppn);
+}
+
+#[allow(unused)]
+pub fn frame_allocator_test() {
+    let mut v: Vec<FrameTracker> = Vec::new();
+    for i in 0..5 {
+        let frame = frame_alloc().unwrap();
+        println!("{:?}", frame);
+        v.push(frame);
+    }
+    v.clear();
+    for i in 0..5 {
+        let frame = frame_alloc().unwrap();
+        println!("{:?}", frame);
+        v.push(frame);
+    }
+    drop(v);
+    println!("frame_allocator_test passed!");
+}

os/src/mm/mod.rs

@@ -1,4 +1,11 @@
 mod heap_allocator;
+mod address;
+mod frame_allocator;
 
-pub use heap_allocator::init_heap;
+pub use address::{PhysAddr, VirtAddr, PhysPageNum, VirtPageNum};
-pub use heap_allocator::heap_test;
+pub use frame_allocator::{FrameTracker, frame_alloc};
+
+pub fn init() {
+    heap_allocator::init_heap();
+    frame_allocator::init_frame_allocator();
+}

user/Cargo.lock

@@ -1,5 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-[[package]]
-name = "user_lib"
-version = "0.1.0"