Layer 1 test not passing

1 files changed, 166 insertions, 35 deletions

diff --git a/src/memory/cached_block.rs b/src/memory/cached_block.rs
index 0c401ff..9e266ef 100644
--- a/src/memory/cached_block.rs
+++ b/src/memory/cached_block.rs
@@ -1,7 +1,10 @@
-use and_then_some::BoolExt;
+use crate::block_device::{BlockDevice, BLOCK_SIZE};
+use crate::disk::block::Block;
 use crate::AyaFS;
-use crate::block_device::BLOCK_SIZE;
-use crate::disk::data_block::{Block, DataBlock};
+use and_then_some::BoolExt;
+use lru::LruCache;
+use std::num::NonZeroUsize;
+use std::sync::Arc;
 
 #[derive(Clone)]
 pub struct CachedBlock<T: Block> {
@@ -28,39 +31,24 @@ pub fn convert<U: Block, T: Block>(input_block: &CachedBlock<U>) -> &CachedBlock
     unsafe { &*block }
 }
 
-impl AyaFS {
-    pub(crate) fn update_block<T: Block>(&mut self, block: CachedBlock<T>) -> bool {
-        if self.cached_blocks.contains(&block.index) {
-            let data_block = convert::<T, DataBlock>(&block).clone();
-            self.cached_blocks.push(block.index, data_block);
-            true
-        } else {
-            false
-        }
-    }
-    pub(crate) fn get_block<T: Block>(&mut self, index: usize) -> Option<&CachedBlock<T>> {
-        self.load_block(index)
-            .and_then(|| self.cached_blocks.get(&index).map(convert::<DataBlock, T>))
-    }
+pub(crate) struct BlockCache<T: Block> {
+    device: Arc<dyn BlockDevice>,
+    cache: LruCache<usize, CachedBlock<T>>,
+}
 
-    pub(crate) fn get_block_mut<T: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<T>> {
-        self.load_block(index).and_then(|| {
-            self.cached_blocks
-                .get_mut(&index)
-                .map(convert_mut::<DataBlock, T>)
-        })
+impl<T: Block> BlockCache<T> {
+    pub(crate) fn new(device: Arc<dyn BlockDevice>, cache_size: usize) -> Self {
+        Self {
+            device,
+            cache: LruCache::new(NonZeroUsize::new(cache_size).unwrap()),
+        }
     }
 
     pub(crate) fn load_block(&mut self, index: usize) -> bool {
-        // 反正我自己保证所有实现了 Block trait 的数据结构都是 4K bytes 长, 来回 cast 没问题
-        // 如果 block cache 里没有这个 block
-        if self.cached_blocks.contains(&index) == false {
-            if self.data_bitmap.query(index) == false {
-                return false;
-            } // 先看这个 block 是不是 valid, 不 valid 直接返回 None
-            let block = DataBlock::default();
+        if self.cache.contains(&index) == false {
+            let block = T::default();
             let buffer = unsafe {
-                std::slice::from_raw_parts_mut(&block as *const DataBlock as *mut u8, BLOCK_SIZE)
+                std::slice::from_raw_parts_mut(&block as *const T as *mut u8, BLOCK_SIZE)
             };
             self.device.read(index, buffer);
             let cached_block = CachedBlock {
@@ -68,17 +56,160 @@ impl AyaFS {
                 index,
                 dirty: false,
             };
-            if let Some((old_index, old_block)) = self.cached_blocks.push(index, cached_block) {
+            if let Some((old_index, old_block)) = self.cache.push(index, cached_block) {
                 assert_ne!(old_index, index); // 只有 block 不在 cache 里的时候才会插入
                 if old_block.dirty {
-                    let old_block_ptr = &old_block.block as *const DataBlock as *mut u8;
+                    let old_block_ptr = &old_block.block as *const T as *mut u8;
                     let old_block_buffer =
                         unsafe { std::slice::from_raw_parts(old_block_ptr, BLOCK_SIZE) };
                     self.device.write(old_index, old_block_buffer);
                 }
-            } // 如果 valid 就放到 block cache 里, 同时将（可能）被驱逐的 block 依据其是否为脏块进行写回
+            }
         }
-
         true
     }
+
+    /// 从 LRU cache 里获取一个 block 的引用, 如果没有在 cache 中会加载.
+    pub(crate) fn get_block<U: Block>(&mut self, index: usize) -> Option<&CachedBlock<U>> {
+        self.load_block(index)
+            .and_then(|| self.cache.get(&index).map(convert::<T, U>))
+    }
+
+    /// 从 LRU cache 里获取一个 block 的可变引用, 如果没有在 cache 中会加载.
+    pub(crate) fn get_block_mut<U: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<U>> {
+        self.load_block(index)
+            .and_then(|| self.cache.get_mut(&index).map(convert_mut::<T, U>))
+    }
+
+    /// 从 LRU cache 中读取一个 block 的引用, *不会* 影响 LRU cache 的结构, 如果没有在 cache 中不会加载.
+    pub(crate) fn peek_block<U: Block>(&self, index: usize) -> Option<&CachedBlock<U>> {
+        self.cache.peek(&index).map(convert::<T, U>)
+    }
+
+    /// 从 LRU cache 中读取一个 block 的可变引用, *不会* 影响 LRU cache 的结构, 如果没有在 cache 中不会加载.
+    pub(crate) fn peek_block_mut<U: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<U>> {
+        self.cache.peek_mut(&index).map(convert_mut::<T, U>)
+    }
+
+    pub(crate) fn update_block<U: Block>(&mut self, block: CachedBlock<U>) -> bool {
+        if self.cache.contains(&block.index) {
+            let data_block = convert::<U, T>(&block).clone();
+            self.cache.push(block.index, data_block);
+            true
+        } else {
+            false
+        }
+    }
+
+    fn pop(&mut self, entry: &usize) -> Option<CachedBlock<T>> {
+        self.cache.pop(entry)
+    }
+}
+
+impl AyaFS {
+    pub(crate) fn load_block(&mut self, index: usize) -> bool {
+        if !self.data_bitmap.query(index) {
+            self.cached_blocks.pop(&index);
+            // deallocate 时只更新 bitmap 没有动 cache, lazy 地驱逐 cache 中的无效 entry.
+            return false;
+        }
+        self.cached_blocks.load_block(index)
+    }
+
+    pub(crate) fn get_block<T: Block>(&mut self, index: usize) -> Option<&CachedBlock<T>> {
+        self.data_bitmap
+            .query(index)
+            .and_then(|| self.cached_blocks.get_block::<T>(index))
+    }
+
+    pub(crate) fn get_block_mut<T: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<T>> {
+        self.data_bitmap
+            .query(index)
+            .and_then(|| self.cached_blocks.get_block_mut::<T>(index))
+    }
+
+    pub(crate) fn peek_block<T: Block>(&self, index: usize) -> Option<&CachedBlock<T>> {
+        self.data_bitmap
+            .query(index)
+            .and_then(|| self.cached_blocks.peek_block::<T>(index))
+    }
+
+    pub(crate) fn peek_block_mut<T: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<T>> {
+        self.data_bitmap
+            .query(index)
+            .and_then(|| self.cached_blocks.peek_block_mut::<T>(index))
+    }
+
+    pub(crate) fn update_block<T: Block>(&mut self, block: CachedBlock<T>) -> bool {
+        self.cached_blocks.update_block(block)
+    }
+
+    // pub(crate) fn update_block<T: Block>(&mut self, block: CachedBlock<T>) -> bool {
+    //     if self.cached_blocks.contains(&block.index) {
+    //         let data_block = convert::<T, DataBlock>(&block).clone();
+    //         self.cached_blocks.push(block.index, data_block);
+    //         true
+    //     } else {
+    //         false
+    //     }
+    // }
+    //
+    // /// 从 LRU cache 里获取一个 block 的引用, 如果没有在 cache 中会加载.
+    // pub(crate) fn get_block<T: Block>(&mut self, index: usize) -> Option<&CachedBlock<T>> {
+    //     self.load_block(index)
+    //         .and_then(|| self.cached_blocks.get(&index).map(convert::<DataBlock, T>))
+    // }
+    //
+    // /// 从 LRU cache 里获取一个 block 的可变引用, 如果没有在 cache 中会加载.
+    // pub(crate) fn get_block_mut<T: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<T>> {
+    //     self.load_block(index).and_then(|| {
+    //         self.cached_blocks
+    //             .get_mut(&index)
+    //             .map(convert_mut::<DataBlock, T>)
+    //     })
+    // }
+    //
+    // /// 从 LRU cache 中读取一个 block 的引用, *不会* 影响 LRU cache 的结构, 如果没有在 cache 中不会加载.
+    // pub(crate) fn peek_block<T: Block>(&self, index: usize) -> Option<&CachedBlock<T>> {
+    //     self.cached_blocks.peek(&index).map(convert::<DataBlock, T>)
+    // }
+    //
+    // /// 从 LRU cache 中读取一个 block 的可变引用, *不会* 影响 LRU cache 的结构, 如果没有在 cache 中不会加载.
+    // pub(crate) fn peek_block_mut<T: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<T>> {
+    //     self.cached_blocks.peek_mut(&index).map(convert_mut::<DataBlock, T>)
+    // }
+    //
+    // pub(crate) fn load_block(&mut self, index: usize) -> bool {
+    //     // 先看这个 block 是不是 valid, 不 valid 直接返回 false.
+    //     if !self.data_bitmap.query(index) {
+    //         self.cached_blocks.pop(&index);
+    //         // deallocate 时只更新 bitmap 没有动 cache, lazy 地驱逐 cache 中的无效 entry.
+    //         return false;
+    //     }
+    //
+    //     // 接下来这个 block 一定 valid. 如果 cache 里没有这个 block 就把它 load 到 cache 里
+    //     if self.cached_blocks.contains(&index) == false {
+    //         let block = DataBlock::default();
+    //         let buffer = unsafe {
+    //             std::slice::from_raw_parts_mut(&block as *const DataBlock as *mut u8, BLOCK_SIZE)
+    //         };
+    //         self.device.read(index, buffer);
+    //         let cached_block = CachedBlock {
+    //             block,
+    //             index,
+    //             dirty: false,
+    //         };
+    //         if let Some((old_index, old_block)) = self.cached_blocks.push(index, cached_block) {
+    //             assert_ne!(old_index, index); // 只有 block 不在 cache 里的时候才会插入
+    //             if old_block.dirty {
+    //                 let old_block_ptr = &old_block.block as *const DataBlock as *mut u8;
+    //                 let old_block_buffer =
+    //                     unsafe { std::slice::from_raw_parts(old_block_ptr, BLOCK_SIZE) };
+    //                 self.device.write(old_index, old_block_buffer);
+    //             }
+    //         }
+    //     }
+    //
+    //     true
+    // }
 }