Refactor workspace

23 files changed, 0 insertions, 3800 deletions

diff --git a/ayafs/src/block_device/disk.rs b/ayafs/src/block_device/disk.rs
deleted file mode 100644
index 3f0b018..0000000
--- a/ayafs/src/block_device/disk.rs
+++ /dev/null
@@ -1,47 +0,0 @@
-use std::cell::RefCell;
-use std::fs::File;
-use std::io::{Read, Seek, SeekFrom, Write};
-use std::path::{Path, PathBuf};
-use crate::block_device::{BLOCK_SIZE, BlockDevice};
-
-pub struct Disk {
-    disk_path: PathBuf,
-    device: RefCell<File>,
-}
-
-impl Disk {
-    pub fn new(disk_path: PathBuf) -> Self {
-        let device = File::options()
-            .read(true)
-            .write(true)
-            .open(disk_path.as_path())
-            .unwrap();
-        // let device = File::open(disk_path.as_path()).unwrap();
-        Self {
-            disk_path,
-            device: RefCell::new(device),
-        }
-    }
-}
-
-impl BlockDevice for Disk {
-    fn read(&self, block_id: usize, buffer: &mut [u8]) {
-        let mut device = self.device.borrow_mut();
-        device
-            .seek(SeekFrom::Start((block_id * BLOCK_SIZE) as u64))
-            .expect("Unable to seek!");
-        device
-            .read_exact(buffer)
-            .expect("Failed to read 4096 bytes!");
-    }
-
-    fn write(&self, block_id: usize, buffer: &[u8]) {
-        let mut device = self.device.borrow_mut();
-        device
-            .seek(SeekFrom::Start((block_id * BLOCK_SIZE) as u64))
-            .expect("Unable to seek!");
-        device
-            .write_all(buffer)
-            .expect("Unable to write 4096 bytes!");
-    }
-}
\ No newline at end of file
diff --git a/ayafs/src/block_device/memory_disk.rs b/ayafs/src/block_device/memory_disk.rs
deleted file mode 100644
index 0639d3e..0000000
--- a/ayafs/src/block_device/memory_disk.rs
+++ /dev/null
@@ -1,33 +0,0 @@
-use crate::block_device::{BlockDevice, BLOCK_SIZE};
-use std::cell::RefCell;
-
-#[repr(C)]
-pub struct MemoryDisk {
-    /// Emulating a block device with a segment of RAM,
-    /// which is 64MiB == 4KiB per block * 16384 blocks
-    pub arena: RefCell<Vec<u8>>,
-}
-
-impl MemoryDisk {
-    pub fn new(block_number: usize) -> Self {
-        Self {
-            arena: RefCell::new(vec![0u8; BLOCK_SIZE * block_number]),
-        }
-    }
-}
-
-impl BlockDevice for MemoryDisk {
-    fn read(&self, block_id: usize, buffer: &mut [u8]) {
-        let block_front = block_id * BLOCK_SIZE;
-        let block_back = block_front + BLOCK_SIZE;
-        let arena = self.arena.borrow();
-        buffer.copy_from_slice(&arena[block_front..block_back]);
-    }
-
-    fn write(&self, block_id: usize, buffer: &[u8]) {
-        let block_front = block_id * BLOCK_SIZE;
-        let block_back = block_front + BLOCK_SIZE;
-        let mut arena = self.arena.borrow_mut();
-        arena[block_front..block_back].copy_from_slice(buffer);
-    }
-}
diff --git a/ayafs/src/block_device/mod.rs b/ayafs/src/block_device/mod.rs
deleted file mode 100644
index a1e6544..0000000
--- a/ayafs/src/block_device/mod.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-/// Abstracts for block devices.
-/// Currently only a mock memory disk.
-pub mod memory_disk;
-pub mod disk;
-
-pub const BLOCK_SIZE: usize = 4096;
-pub trait BlockDevice {
-    fn read(&self, block_id: usize, buffer: &mut [u8]);
-    fn write(&self, block_id: usize, buffer: &[u8]);
-}
diff --git a/ayafs/src/disk/allocation.rs b/ayafs/src/disk/allocation.rs
deleted file mode 100644
index a187fad..0000000
--- a/ayafs/src/disk/allocation.rs
+++ /dev/null
@@ -1,542 +0,0 @@
-use crate::disk::block::{
-    Block, DataBlock, DoubleIndirectBlock, IndirectBlock, TripleIndirectBlock,
-};
-use crate::disk::inode::{Inode, DIRECT_NUMBER, ENTRY_PER_BLOCK};
-use crate::memory::cached_block::{convert, CachedBlock};
-use crate::AyaFS;
-use libc::c_int;
-use log::debug;
-
-impl AyaFS {
-    /// 为 Inode 分配新 block, 返回 block 的编号和它在 inode 内的编号
-    pub(crate) fn allocate_block_for(&mut self, inode: &mut Inode) -> Option<(u32, usize)> {
-        // 先看这个 inode 的 direct block 有没有空闲
-        for (index_within_direct, index) in inode.direct.iter_mut().enumerate() {
-            if !self.data_bitmap.query(*index as usize) {
-                let block_index = self.data_bitmap.allocate().unwrap() as u32;
-                // println!("allocating {} for direct", block_index);
-                *index = block_index;
-                inode.n_blocks += 1;
-                // 初始化这个 block
-                self.init_block(block_index as usize);
-                // 当调用 get_inode_mut 拿出 &mut Inode 的时候对应的 block 在 cache 里已经脏了
-                return Some((block_index, index_within_direct));
-            }
-        }
-
-        // direct block 全部分配完了, 先检查 indirect block 有没有分配, 没有就分配一个
-        if !self.data_bitmap.query(inode.single_indirect as usize) {
-            inode.single_indirect = self
-                .data_bitmap
-                .allocate()
-                .expect("No free space for new block") as u32;
-            self.init_block(inode.single_indirect as usize);
-            // println!("allocating {} for indirect", inode.single_indirect);
-        }
-        // 在 indirect block 里尝试分配
-        if let Some((block_index, index_within_indirect)) =
-            self.allocate_in_indirect(inode.single_indirect)
-        {
-            // println!("allocating {} in indirect", block_index);
-            inode.n_blocks += 1;
-
-            let index_within_block = DIRECT_NUMBER + index_within_indirect;
-            return Some((block_index, index_within_block));
-        }
-
-        // direct & indirect block 全部分配完了, 先检查 double indirect block 有没有分配, 没有就分配一个
-        if !self.data_bitmap.query(inode.double_indirect as usize) {
-            inode.double_indirect = self
-                .data_bitmap
-                .allocate()
-                .expect("No free space for new block") as u32;
-            self.init_block(inode.double_indirect as usize);
-            // println!("allocating {} for double indirect", inode.double_indirect);
-        }
-        // 在 double indirect block 里尝试分配
-        if let Some((block_index, index_within_double)) =
-            self.alloc_in_double_indirect(inode.double_indirect)
-        {
-            // println!("allocating {} in double indirect", block_index);
-            inode.n_blocks += 1;
-            let index_within_block = DIRECT_NUMBER + ENTRY_PER_BLOCK + index_within_double;
-            return Some((block_index, index_within_block));
-        }
-
-        // direct, indirect & double indirect block 全部分配完了, 先检查 triple indirect block 有没有分配, 没有就分配一个
-        if !self.data_bitmap.query(inode.triple_indirect as usize) {
-            inode.triple_indirect = self
-                .data_bitmap
-                .allocate()
-                .expect("No free space for new block") as u32;
-            self.init_block(inode.triple_indirect as usize);
-            // println!("allocating {} for triple indirect", inode.triple_indirect);
-        }
-        // 在 double indirect block 里尝试分配
-        if let Some((block_index, index_within_triple)) =
-            self.alloc_in_triple_indirect(inode.triple_indirect)
-        {
-            // println!("allocating {} in triple indirect", block_index);
-            inode.n_blocks += 1;
-            let index_within_block = DIRECT_NUMBER
-                + ENTRY_PER_BLOCK
-                + ENTRY_PER_BLOCK * ENTRY_PER_BLOCK
-                + index_within_triple;
-            return Some((block_index, index_within_block));
-        }
-        None
-    }
-
-    fn allocate_in_indirect(&mut self, indirect_entry: u32) -> Option<(u32, usize)> {
-        // 取出 single indirect block, 尝试在里面分配
-        let indirect_entry = indirect_entry as usize;
-        // println!("finding indirect block with number {}, bitmap says {}", indirect_entry, self.data_bitmap.query(indirect_entry));
-
-        if let Some(block) = self
-            .get_block(indirect_entry)
-            .map(convert::<DataBlock, IndirectBlock>)
-        {
-            // println!("found indirect block with number {}", indirect_entry);
-            let mut indirect_block = block.clone();
-            for (index_within_indirect, entry) in
-                indirect_block.block.entries.iter_mut().enumerate()
-            {
-                if self.data_bitmap.query(*entry as usize) == false {
-                    indirect_block.dirty = true; // 把这个块标记为 dirty
-                    let block_index = self.data_bitmap.allocate().expect("No free space") as u32;
-                    self.init_block(block_index as usize);
-                    *entry = block_index;
-                    self.update_block(indirect_block);
-                    return Some((block_index, index_within_indirect));
-                }
-            }
-        }
-        None
-    }
-
-    fn alloc_in_double_indirect(&mut self, double_indirect_entry: u32) -> Option<(u32, usize)> {
-        let double_indirect_entry = double_indirect_entry as usize;
-
-        if let Some(block) = self
-            .get_block(double_indirect_entry)
-            .map(convert::<DataBlock, DoubleIndirectBlock>)
-        {
-            let mut double_indirect_block = block.clone();
-            let mut double_indirect_modified = false;
-            for (index_within_double_indirect, indirect_entry) in
-                double_indirect_block.block.indirect.iter_mut().enumerate()
-            {
-                if self.data_bitmap.query(*indirect_entry as usize) == false {
-                    double_indirect_block.dirty = true;
-                    double_indirect_modified = true;
-
-                    let indirect_index = self.data_bitmap.allocate().expect("No free space");
-                    *indirect_entry = indirect_index as u32;
-                    self.init_block(indirect_index);
-                }
-
-                if let Some((block_index, index_within_indirect)) =
-                    self.allocate_in_indirect(*indirect_entry)
-                {
-                    if double_indirect_modified {
-                        self.update_block(double_indirect_block);
-                    }
-                    let index_within_double =
-                        index_within_double_indirect * ENTRY_PER_BLOCK + index_within_indirect;
-                    return Some((block_index, index_within_double));
-                }
-            }
-        }
-        None
-    }
-
-    fn alloc_in_triple_indirect(&mut self, triple_indirect_entry: u32) -> Option<(u32, usize)> {
-        let triple_indirect_entry = triple_indirect_entry as usize;
-
-        if let Some(block) = self
-            .get_block(triple_indirect_entry)
-            .map(convert::<DataBlock, TripleIndirectBlock>)
-        {
-            let mut triple_indirect_block = block.clone();
-            let mut triple_indirect_modified = false;
-            for (index_within_triple_indirect, double_indirect_entry) in triple_indirect_block
-                .block
-                .double_indirect
-                .iter_mut()
-                .enumerate()
-            {
-                if self.data_bitmap.query(*double_indirect_entry as usize) == false {
-                    triple_indirect_block.dirty = true;
-                    triple_indirect_modified = true;
-
-                    let double_indirect_index = self.data_bitmap.allocate().expect("No free space");
-                    *double_indirect_entry = double_indirect_index as u32;
-                    self.init_block(double_indirect_index)
-                }
-                if let Some((block_index, index_within_double_indirect)) =
-                    self.alloc_in_double_indirect(*double_indirect_entry)
-                {
-                    if triple_indirect_modified {
-                        self.update_block(triple_indirect_block);
-                    }
-                    let index_within_triple =
-                        index_within_triple_indirect * ENTRY_PER_BLOCK * ENTRY_PER_BLOCK
-                            + index_within_double_indirect;
-                    return Some((block_index, index_within_triple));
-                }
-            }
-        }
-        None
-    }
-}
-
-impl AyaFS {
-    pub(crate) fn deallocate_all_blocks_for(&mut self, inode: &Inode) -> Result<(), c_int> {
-        // 遍历 direct block 并删除
-        for block_index in inode.direct {
-            self.data_bitmap.deallocate(block_index as usize);
-        }
-
-        // 遍历 indirect block 并删除
-        if self.data_bitmap.query(inode.single_indirect as usize) {
-            let indirect = self
-                .get_block::<IndirectBlock>(inode.single_indirect as usize)
-                .unwrap();
-            for block_index in indirect.block.entries {
-                self.data_bitmap.deallocate(block_index as usize);
-            }
-            self.data_bitmap.deallocate(inode.single_indirect as usize);
-        }
-
-        // 遍历 double indirect block 并删除
-        if self.data_bitmap.query(inode.double_indirect as usize) {
-            let double_indirect = self
-                .get_block::<DoubleIndirectBlock>(inode.double_indirect as usize)
-                .unwrap();
-            for indirect_block_index in double_indirect.block.indirect {
-                if let Some(indirect) =
-                    self.get_block::<IndirectBlock>(indirect_block_index as usize)
-                {
-                    for block_index in indirect.block.entries {
-                        self.data_bitmap.deallocate(block_index as usize);
-                    }
-                    self.data_bitmap.deallocate(indirect_block_index as usize);
-                }
-            }
-            self.data_bitmap.deallocate(inode.double_indirect as usize);
-        }
-
-        // 遍历 triple indirect block 并删除
-        if self.data_bitmap.query(inode.triple_indirect as usize) {
-            let triple_indirect = self
-                .get_block::<TripleIndirectBlock>(inode.triple_indirect as usize)
-                .unwrap();
-            for double_indirect_block_index in triple_indirect.block.double_indirect {
-                if let Some(double_indirect) =
-                    self.get_block::<DoubleIndirectBlock>(double_indirect_block_index as usize)
-                {
-                    for indirect_block_index in double_indirect.block.indirect {
-                        if let Some(indirect) =
-                            self.get_block::<IndirectBlock>(indirect_block_index as usize)
-                        {
-                            for block_index in indirect.block.entries {
-                                self.data_bitmap.deallocate(block_index as usize);
-                            }
-                            self.data_bitmap.deallocate(indirect_block_index as usize);
-                        }
-                    }
-                    self.data_bitmap
-                        .deallocate(double_indirect_block_index as usize);
-                }
-            }
-            self.data_bitmap.deallocate(inode.triple_indirect as usize);
-        }
-
-        Ok(())
-    }
-
-    /// 从 inode 中删去最后一个 block
-    pub(crate) fn deallocate_block_for(&mut self, inode: &mut Inode) -> Option<u32> {
-        // 如果 triple indirect 块存在, 则尝试从中销毁一个块
-        if self.data_bitmap.query(inode.triple_indirect as usize) {
-            if let Some(block_index) = self.deallocate_from_triple_indirect(inode.triple_indirect) {
-                inode.n_blocks -= 1;
-                return Some(block_index); // 销毁成功, 直接返回
-            } else {
-                // 销毁失败, 说明 triple indirect 空了, 把它也销毁.
-                self.data_bitmap.deallocate(inode.triple_indirect as usize);
-                inode.triple_indirect = 0; // 这个地方理论上应该不用?
-            }
-        }
-        // 如果 double indirect 块存在, 则从其中销毁
-        if self.data_bitmap.query(inode.double_indirect as usize) {
-            if let Some(block_index) = self.deallocate_from_double_indirect(inode.double_indirect) {
-                inode.n_blocks -= 1;
-                return Some(block_index);
-            } else {
-                self.data_bitmap.deallocate(inode.double_indirect as usize);
-                inode.double_indirect = 0; // 这个地方理论上应该不用?
-            }
-        }
-        // 如果 indirect 块存在, 则从其中销毁
-        if self.data_bitmap.query(inode.single_indirect as usize) {
-            if let Some(block_index) = self.deallocate_from_indirect(inode.single_indirect) {
-                inode.n_blocks -= 1;
-                return Some(block_index);
-            } else {
-                self.data_bitmap.deallocate(inode.single_indirect as usize);
-                inode.single_indirect = 0; // 这个地方理论上应该不用?
-            }
-        }
-        // 都没有，直接从 direct 块中销毁
-        for entry in inode.direct.iter_mut().rev() {
-            if self.data_bitmap.query(*entry as usize) {
-                let index = std::mem::replace(entry, 0); // let index = *entry; *entry = 0;
-                inode.n_blocks -= 1;
-                self.data_bitmap.deallocate(index as usize);
-                return Some(index);
-            }
-        }
-        None
-    }
-
-    fn deallocate_from_triple_indirect(&mut self, triple_indirect_entry: u32) -> Option<u32> {
-        let triple_indirect_entry = triple_indirect_entry as usize;
-        if let Some(triple_indirect_block) = self
-            .get_block(triple_indirect_entry)
-            .map(convert::<DataBlock, TripleIndirectBlock>)
-        {
-            let mut triple_indirect_block = triple_indirect_block.clone();
-            let mut block_modified = false;
-            for double_indirect_entry in
-                triple_indirect_block.block.double_indirect.iter_mut().rev()
-            {
-                // 如果这个位置的 double indirect 存在
-                if self.data_bitmap.query(*double_indirect_entry as usize) {
-                    // 尝试从中销毁一个块
-                    if let Some(block_index) =
-                        self.deallocate_from_double_indirect(*double_indirect_entry)
-                    {
-                        if block_modified {
-                            self.update_block(triple_indirect_block);
-                        }
-                        return Some(block_index); // 成功则直接返回
-                    } else {
-                        // 失败则把这个 double indirect 销毁
-                        let double_indirect_entry_to_deallocate =
-                            std::mem::replace(double_indirect_entry, 0);
-                        self.data_bitmap
-                            .deallocate(double_indirect_entry_to_deallocate as usize);
-                        triple_indirect_block.dirty = true;
-                        block_modified = true;
-                    }
-                }
-            }
-            if block_modified {
-                self.update_block(triple_indirect_block);
-            }
-        }
-        None
-    }
-
-    fn deallocate_from_double_indirect(&mut self, double_indirect_entry: u32) -> Option<u32> {
-        let double_indirect_entry = double_indirect_entry as usize;
-        if let Some(double_indirect_block) = self
-            .get_block(double_indirect_entry)
-            .map(convert::<DataBlock, DoubleIndirectBlock>)
-        {
-            let mut double_indirect_block = double_indirect_block.clone();
-            let mut block_modified = false;
-            for indirect_entry in double_indirect_block.block.indirect.iter_mut().rev() {
-                // 如果这个位置的 indirect 存在
-                if self.data_bitmap.query(*indirect_entry as usize) {
-                    // 尝试从中销毁一个块
-                    if let Some(block_index) = self.deallocate_from_indirect(*indirect_entry) {
-                        if block_modified {
-                            self.update_block(double_indirect_block);
-                        }
-                        return Some(block_index); // 成功则直接返回
-                    } else {
-                        // 失败则把这个 indirect 销毁
-                        let indirect_entry_to_deallocate = std::mem::replace(indirect_entry, 0);
-                        self.data_bitmap
-                            .deallocate(indirect_entry_to_deallocate as usize);
-                        double_indirect_block.dirty = true;
-                        block_modified = true;
-                    }
-                }
-            }
-            if block_modified {
-                self.update_block(double_indirect_block);
-            }
-        }
-        None
-    }
-
-    fn deallocate_from_indirect(&mut self, indirect_entry: u32) -> Option<u32> {
-        let indirect_entry = indirect_entry as usize;
-        if let Some(indirect_block) = self
-            .get_block(indirect_entry)
-            .map(convert::<DataBlock, IndirectBlock>)
-        {
-            let mut indirect_block = indirect_block.clone();
-            // 遍历 indirect block 里的每个 block
-            for entry in indirect_block.block.entries.iter_mut().rev() {
-                // 如果这个 block 存在, 销毁它
-                if self.data_bitmap.query(*entry as usize) {
-                    let entry_to_deallocate = std::mem::replace(entry, 0);
-
-                    self.data_bitmap.deallocate(entry_to_deallocate as usize);
-                    indirect_block.dirty = true;
-                    self.update_block(indirect_block);
-
-                    return Some(entry_to_deallocate);
-                }
-            }
-        }
-        None
-    }
-}
-
-impl AyaFS {
-    pub(crate) fn get_block_index(
-        &mut self,
-        inode: &Inode,
-        mut block_index_within_inode: usize,
-    ) -> Option<usize> {
-        debug!(
-            "get_block_index(block_index_within_inode: {})",
-            block_index_within_inode
-        );
-        // direct block
-        if block_index_within_inode < DIRECT_NUMBER {
-            let block_index = inode.direct[block_index_within_inode] as usize;
-            debug!("  get_block_index -> direct");
-            return if self.data_bitmap.query(block_index) {
-                debug!("  get_block_index -> direct -> ✓");
-                Some(block_index)
-            } else {
-                debug!("  get_block_index -> direct -> ×");
-                None
-            };
-        } else {
-            block_index_within_inode -= DIRECT_NUMBER;
-        }
-
-        // indirect block
-        let indirect_number = ENTRY_PER_BLOCK;
-        if block_index_within_inode < indirect_number {
-            return if let Some(indirect_block) =
-                self.get_block::<IndirectBlock>(inode.single_indirect as usize)
-            {
-                debug!("  get_block_index -> indirect");
-                let block_index = indirect_block.block.entries[block_index_within_inode] as usize;
-                if self.data_bitmap.query(block_index) {
-                    debug!("  get_block_index -> indirect -> ✓");
-                    Some(block_index)
-                } else {
-                    debug!("  get_block_index -> indirect -> ×");
-                    None
-                }
-            } else {
-                debug!("  get_block_index -> indirect -> ×");
-                None
-            };
-        } else {
-            block_index_within_inode -= indirect_number;
-        }
-
-        // double indirect block
-        let double_indirect_number = ENTRY_PER_BLOCK * ENTRY_PER_BLOCK;
-        if block_index_within_inode < double_indirect_number {
-            if let Some(double_indirect_block) =
-                self.get_block::<DoubleIndirectBlock>(inode.double_indirect as usize)
-            {
-                debug!("  get_block_index -> double_indirect");
-                // 取出 double indirect block
-                let indirect_block_index = double_indirect_block.block.indirect
-                    [block_index_within_inode / ENTRY_PER_BLOCK]
-                    as usize;
-                // 要找的 entry 在 double indirect block 中的第几个 indirect block
-                if let Some(indirect_block) = self.get_block::<IndirectBlock>(indirect_block_index)
-                {
-                    debug!("  get_block_index -> double_indirect -> indirect");
-                    let block_index = indirect_block.block.entries
-                        [block_index_within_inode % ENTRY_PER_BLOCK]
-                        as usize;
-                    // 拿到 DirectoryBlock 的 index
-                    return if self.data_bitmap.query(block_index) {
-                        debug!("  get_block_index -> double_indirect -> indirect -> ✓");
-                        Some(block_index)
-                    } else {
-                        debug!("  get_block_index -> double_indirect -> indirect -> ×");
-                        None
-                    };
-                }
-            }
-            return None;
-        } else {
-            block_index_within_inode -= double_indirect_number;
-        }
-
-        // triple indirect block
-        if let Some(triple_indirect_block) =
-            self.get_block::<TripleIndirectBlock>(inode.triple_indirect as usize)
-        {
-            // 取出 triple indirect block
-            let double_indirect_block_index = triple_indirect_block.block.double_indirect
-                [block_index_within_inode / (ENTRY_PER_BLOCK * ENTRY_PER_BLOCK)]
-                as usize;
-            // 要找的 entry 在 triple indirect block 中的第几个 double indirect block
-            if let Some(double_indirect_block) =
-                self.get_block::<DoubleIndirectBlock>(double_indirect_block_index)
-            {
-                // 取出 double indirect block
-                let indirect_block_index = double_indirect_block.block.indirect
-                    [block_index_within_inode % (ENTRY_PER_BLOCK * ENTRY_PER_BLOCK)
-                        / ENTRY_PER_BLOCK] as usize;
-                // 要找的 entry 在 double indirect block 中的第几个 indirect block
-                if let Some(indirect_block) = self.get_block::<IndirectBlock>(indirect_block_index)
-                {
-                    let block_index = indirect_block.block.entries
-                        [block_index_within_inode % ENTRY_PER_BLOCK]
-                        as usize;
-                    // DirectoryBlock 的 index
-                    return if self.data_bitmap.query(block_index) {
-                        Some(block_index)
-                    } else {
-                        None
-                    };
-                }
-            }
-        }
-
-        None
-    }
-
-    pub(crate) fn access_block<T: Block>(
-        &mut self,
-        inode: &Inode,
-        block_index_within_inode: usize,
-    ) -> Option<&CachedBlock<T>> {
-        self.get_block_index(inode, block_index_within_inode)
-            .map(|block_index| {
-                self.get_block::<T>(block_index).unwrap() // 可以 unwrap 吧这里 ??
-            })
-    }
-
-    pub(crate) fn access_block_mut<T: Block>(
-        &mut self,
-        inode: &Inode,
-        block_index_within_inode: usize,
-    ) -> Option<&mut CachedBlock<T>> {
-        self.get_block_index(inode, block_index_within_inode)
-            .map(|block_index| {
-                debug!(
-                    "access_block_mut(index: {}) found",
-                    block_index_within_inode
-                );
-                self.get_block_mut::<T>(block_index).unwrap() // 可以 unwrap 吧这里 ??
-            })
-    }
-}
diff --git a/ayafs/src/disk/bitmap.rs b/ayafs/src/disk/bitmap.rs
deleted file mode 100644
index b68c341..0000000
--- a/ayafs/src/disk/bitmap.rs
+++ /dev/null
@@ -1,48 +0,0 @@
-use crate::block_device::{BlockDevice, BLOCK_SIZE};
-use std::sync::Arc;
-
-pub struct Bitmap {
-    pub starting_block: usize,
-    pub length: usize,
-    pub device: Arc<dyn BlockDevice>,
-    pub data: Vec<u8>,
-}
-
-impl Bitmap {
-    pub(crate) fn new(starting_block: usize, length: usize, device: Arc<dyn BlockDevice>) -> Self {
-        Self {
-            starting_block,
-            length,
-            device,
-            data: vec![0u8; length * BLOCK_SIZE],
-        }
-    }
-    pub(crate) fn allocate(&mut self) -> Option<usize> {
-        for (i, byte) in self.data.iter_mut().enumerate() {
-            let leading_ones = byte.leading_ones();
-            if leading_ones != 8 {
-                *byte |= (1 << (7 - leading_ones)) as u8;
-                return Some(i * 8 + leading_ones as usize);
-            }
-        }
-        None
-    }
-
-    pub(crate) fn query(&self, index: usize) -> bool {
-        if index == 0 {
-            false
-        } else {
-            self.data[index / 8] & ((1 << (7 - index % 8)) as u8) != 0
-        }
-    }
-
-    pub(crate) fn deallocate(&mut self, index: usize) -> bool {
-        if self.query(index) {
-            let mask = !(1u8 << (7 - index % 8));
-            self.data[index / 8] &= mask;
-            true
-        } else {
-            false
-        }
-    }
-}
diff --git a/ayafs/src/disk/block.rs b/ayafs/src/disk/block.rs
deleted file mode 100644
index 73819e2..0000000
--- a/ayafs/src/disk/block.rs
+++ /dev/null
@@ -1,245 +0,0 @@
-use crate::disk::inode::Inode;
-use std::ffi::{OsStr, OsString};
-use std::os::unix::ffi::OsStrExt;
-
-pub trait Block: Default + Clone {}
-
-#[repr(C)]
-#[derive(Clone)]
-pub struct DataBlock(pub(crate) [u8; 4096]);
-
-impl Default for DataBlock {
-    fn default() -> Self {
-        Self([0; 4096])
-    }
-}
-
-impl Block for DataBlock {}
-
-#[repr(C)]
-#[derive(Clone)]
-pub struct InodeBlock {
-    pub(crate) inodes: [Inode; 32],
-}
-
-impl Default for InodeBlock {
-    fn default() -> Self {
-        Self {
-            inodes: [
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-                Inode::empty(),
-            ],
-        }
-    }
-}
-
-impl Block for InodeBlock {}
-
-#[repr(C)]
-#[derive(Clone)]
-pub struct DirectoryEntry {
-    pub inode: u32,
-    pub record_len: u16,
-    pub name_len: u8,
-    pub file_type: u8,
-    pub name: [u8; 256],
-}
-
-impl DirectoryEntry {
-    pub(crate) fn name(&self) -> OsString {
-        let name = &self.name[0..self.name_len as usize];
-        OsStr::from_bytes(name).to_os_string()
-    }
-}
-
-impl Default for DirectoryEntry {
-    fn default() -> Self {
-        Self {
-            inode: 0,
-            record_len: 0,
-            name_len: 0,
-            file_type: 0x0,
-            name: [0; 256],
-        }
-    }
-}
-
-#[repr(C)]
-#[derive(Clone)]
-pub struct DirectoryBlock {
-    pub entries: [DirectoryEntry; 15],
-    pub occupancy: [u8; 2],
-    reserved: [u8; 134],
-}
-
-impl Default for DirectoryBlock {
-    fn default() -> Self {
-        Self {
-            entries: [
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-                DirectoryEntry::default(),
-            ],
-            occupancy: [0x80, 0x00], // 0b1000_0000
-            reserved: [0xFF; 134],
-        }
-    }
-}
-
-impl DirectoryBlock {
-    #[allow(unused)]
-    pub(crate) fn is_full(&self) -> bool {
-        self.occupancy[0] == 0xFF && self.occupancy[1] == 0xFF
-    }
-
-    pub(crate) fn query(&self, mut index: usize) -> bool {
-        if index < 7 {
-            // 0-6, first u8
-            index = index + 1;
-            self.occupancy[0] & (1 << (7 - index)) as u8 != 0
-        } else if index < 15 {
-            // 7-14, second u8
-            index = index - 7;
-            self.occupancy[1] & (1 << (7 - index)) as u8 != 0
-        } else {
-            false
-        }
-    }
-
-    pub(crate) fn allocate(&mut self, mut index: usize) -> bool {
-        if index < 7 {
-            index = index + 1;
-            let mask = (1 << (7 - index)) as u8;
-            if self.occupancy[0] & mask != 0 {
-                false
-            } else {
-                self.occupancy[0] |= mask;
-                true
-            }
-        } else {
-            index = index - 7;
-            let mask = (1 << (7 - index)) as u8;
-            if self.occupancy[1] & mask != 0 {
-                false
-            } else {
-                self.occupancy[1] |= mask;
-                true
-            }
-        }
-    }
-
-    // pub(crate) fn allocate(&mut self) -> Option<usize> {
-    //     if self.occupancy[0] != 0xFF {
-    //         let leading_ones = self.occupancy[0].leading_ones();
-    //         self.occupancy[0] |= (1 << (7 - leading_ones)) as u8;
-    //         Some(leading_ones as usize)
-    //     } else if self.occupancy[1] != 0xFF {
-    //         let leading_ones = self.occupancy[1].leading_ones();
-    //         self.occupancy[1] |= (1 << (7 - leading_ones)) as u8;
-    //         Some(7 + leading_ones as usize)
-    //     } else {
-    //         None
-    //     }
-    // }
-
-    pub(crate) fn deallocate(&mut self, mut index: usize) {
-        if index < 7 {
-            index = index + 1;
-            self.occupancy[0] &= !((1 << (7 - index)) as u8);
-        } else if index < 15 {
-            // 7-14, second u8
-            index = index - 7;
-            self.occupancy[1] &= !((1 << (7 - index)) as u8);
-        }
-    }
-}
-
-impl Block for DirectoryBlock {}
-
-#[repr(C)]
-#[derive(Clone)]
-pub struct IndirectBlock {
-    pub entries: [u32; 1024],
-}
-
-impl Default for IndirectBlock {
-    fn default() -> Self {
-        Self { entries: [0; 1024] }
-    }
-}
-
-impl Block for IndirectBlock {}
-
-#[repr(C)]
-#[derive(Clone)]
-pub struct DoubleIndirectBlock {
-    pub indirect: [u32; 1024],
-}
-
-impl Default for DoubleIndirectBlock {
-    fn default() -> Self {
-        Self {
-            indirect: [0; 1024],
-        }
-    }
-}
-
-impl Block for DoubleIndirectBlock {}
-
-#[repr(C)]
-#[derive(Clone)]
-pub struct TripleIndirectBlock {
-    pub double_indirect: [u32; 1024],
-}
-
-impl Default for TripleIndirectBlock {
-    fn default() -> Self {
-        Self {
-            double_indirect: [0; 1024],
-        }
-    }
-}
-
-impl Block for TripleIndirectBlock {}
diff --git a/ayafs/src/disk/inode.rs b/ayafs/src/disk/inode.rs
deleted file mode 100644
index 0c801ad..0000000
--- a/ayafs/src/disk/inode.rs
+++ /dev/null
@@ -1,312 +0,0 @@
-use crate::utils;
-use bitflags::bitflags;
-use fuser::FileType;
-use crate::block_device::BLOCK_SIZE;
-
-pub const DIRECT_NUMBER: usize = 15;
-
-#[derive(Debug, Clone, Copy)]
-pub struct InodeMode(pub u16);
-
-bitflags! {
-    impl InodeMode: u16 {
-        const IXOTH = 0x0001;
-        const IWOTH = 0x0002;
-        const IROTH = 0x0004;
-        const IXGRP = 0x0008;
-        const IWGRP = 0x0010;
-        const IRGRP = 0x0020;
-        const IXUSR = 0x0040;
-        const IWUSR = 0x0080;
-        const IRUSR = 0x0100;
-        const ISVTX = 0x0200;
-        const ISGID = 0x0400;
-        const ISUID = 0x0800;
-        // These are mutually-exclusive:
-        const IFIFO = 0x1000;
-        const IFCHR = 0x2000;
-        const IFDIR = 0x4000;
-        const IFBLK = 0x6000;
-        const IFREG = 0x8000;
-        const IFLNK = 0xA000;
-        const IFSOCK = 0xC000;
-    }
-}
-
-impl InodeMode {
-    #[allow(unused)]
-    pub(crate) fn exec_other(&self) -> bool {
-        self.0 & Self::IXOTH.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn write_other(&self) -> bool {
-        self.0 & Self::IWOTH.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn read_other(&self) -> bool {
-        self.0 & Self::IROTH.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn exec_group(&self) -> bool {
-        self.0 & Self::IXGRP.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn write_group(&self) -> bool {
-        self.0 & Self::IWGRP.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn read_group(&self) -> bool {
-        self.0 & Self::IRGRP.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn exec_user(&self) -> bool {
-        self.0 & Self::IXUSR.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn write_user(&self) -> bool {
-        self.0 & Self::IWUSR.0 != 0
-    }
-    #[allow(unused)]
-    pub(crate) fn read_user(&self) -> bool {
-        self.0 & Self::IRUSR.0 != 0
-    }
-
-    pub(crate) fn perm(&self) -> u16 {
-        self.0 & 0x0FFF
-    }
-
-    pub(crate) fn is_file(&self) -> bool {
-        (self.0 & 0xF000) == Self::IFREG.0
-    }
-
-    pub(crate) fn is_dir(&self) -> bool {
-        (self.0 & 0xF000) == Self::IFDIR.0
-    }
-
-    pub(crate) fn is_symlink(&self) -> bool {
-        self.0 & 0xF000 == Self::IFLNK.0
-    }
-
-    pub(crate) fn validate(mode_value: u16) -> Option<Self> {
-        let valid_flags: [u16; 7] = [0x1000, 0x2000, 0x4000, 0x6000, 0x8000, 0xA000, 0xC000];
-        valid_flags
-            .contains(&(mode_value & 0xF000))
-            .then(|| Self(mode_value))
-    }
-}
-
-impl From<InodeMode> for FileType {
-    fn from(value: InodeMode) -> Self {
-        let type_flag = value.0 & 0xF000;
-        match type_flag {
-            0x1000 => FileType::NamedPipe,
-            0x2000 => FileType::CharDevice,
-            0x4000 => FileType::Directory,
-            0x6000 => FileType::BlockDevice,
-            0x8000 => FileType::RegularFile,
-            0xA000 => FileType::Symlink,
-            0xC000 => FileType::Socket,
-            _ => panic!("Invalid inode mode {:x}", type_flag),
-        }
-    }
-}
-
-impl From<InodeMode> for u8 {
-    fn from(value: InodeMode) -> Self {
-        utils::from_filetype(value.into())
-    }
-}
-
-/// Pretty much the same with ext2, with minor changes:
-/// - removed OS dependent attributes (osd1 & osd2)
-/// - removed i_faddr since fragmentation is not supported
-/// - changed uid and gid from u16 to u32
-/// - added more direct blocks for a total size of 128 bytes
-/// TODO: do we need to extend time precision?
-#[repr(C)]
-#[derive(Debug, Clone)]
-pub struct Inode {
-    pub mode: InodeMode,
-    pub uid: u32,
-    pub size: u32,
-    pub atime: u32,  // access time, in seconds
-    pub ctime: u32,  // change time, in seconds
-    pub mtime: u32,  // modify time, in seconds
-    pub crtime: u32, // create time, in seconds
-    pub gid: u32,
-    pub n_links: u16,
-    pub n_blocks: u32,
-    pub flags: u32, // TODO: do we actually need this? maybe just return 0
-    pub direct: [u32; DIRECT_NUMBER],
-    pub single_indirect: u32,
-    pub double_indirect: u32,
-    pub triple_indirect: u32,
-    pub generation: u32,
-    pub file_acl: u32,
-    pub dir_acl: u32, // TODO do we have to implement ACL......?
-}
-
-impl Inode {
-    fn new(
-        mode: InodeMode,
-        uid: u32,
-        gid: u32,
-        time: u32,
-        flags: u32,
-        generation: u32,
-        file_acl: u32,
-        dir_acl: u32,
-    ) -> Self {
-        Self {
-            mode,
-            uid,
-            size: 0,
-            atime: time,
-            ctime: time,
-            mtime: time,
-            crtime: time,
-            gid,
-            n_links: 1,
-            n_blocks: 0,
-            flags,
-            direct: [0; DIRECT_NUMBER],
-            single_indirect: 0,
-            double_indirect: 0,
-            triple_indirect: 0,
-            generation,
-            file_acl,
-            dir_acl,
-        }
-    }
-
-    #[allow(unused)]
-    pub fn make_inode(
-        permissions: u16,
-        mode: InodeMode,
-        uid: u32,
-        gid: u32,
-        time: u32,
-        flags: u32,
-        generation: u32,
-        file_acl: u32,
-        dir_acl: u32,
-    ) -> Self {
-        Self::new(
-            InodeMode(permissions) | mode,
-            uid,
-            gid,
-            time,
-            flags,
-            generation,
-            file_acl,
-            dir_acl,
-        )
-    }
-
-    pub fn directory(
-        permissions: u16,
-        uid: u32,
-        gid: u32,
-        time: u32,
-        flags: u32,
-        generation: u32,
-        file_acl: u32,
-        dir_acl: u32,
-    ) -> Self {
-        Self::new(
-            InodeMode(permissions) | InodeMode::IFDIR,
-            uid,
-            gid,
-            time,
-            flags,
-            generation,
-            file_acl,
-            dir_acl,
-        )
-    }
-
-    pub fn file(
-        permissions: u16,
-        uid: u32,
-        gid: u32,
-        time: u32,
-        flags: u32,
-        generation: u32,
-        file_acl: u32,
-        dir_acl: u32,
-    ) -> Self {
-        Self::new(
-            InodeMode(permissions) | InodeMode::IFREG,
-            uid,
-            gid,
-            time,
-            flags,
-            generation,
-            file_acl,
-            dir_acl,
-        )
-    }
-
-    pub fn symlink(
-        permissions: u16,
-        uid: u32,
-        gid: u32,
-        time: u32,
-        flags: u32,
-        generation: u32,
-        file_acl: u32,
-        dir_acl: u32,
-    ) -> Self {
-        Self::new(
-            InodeMode(permissions) | InodeMode::IFLNK,
-            uid,
-            gid,
-            time,
-            flags,
-            generation,
-            file_acl,
-            dir_acl,
-        )
-    }
-
-    pub(crate) fn is_file(&self) -> bool {
-        self.mode.is_file()
-    }
-
-    pub(crate) fn is_dir(&self) -> bool {
-        self.mode.is_dir()
-    }
-
-    pub(crate) fn is_symlink(&self) -> bool {
-        self.mode.is_symlink()
-    }
-
-    pub(crate) fn file_type(&self) -> FileType {
-        self.mode.into()
-    }
-
-    pub fn empty() -> Self {
-        Self {
-            mode: InodeMode(0),
-            uid: 0,
-            size: 0,
-            atime: 0,
-            ctime: 0,
-            mtime: 0,
-            crtime: 0,
-            gid: 0,
-            n_links: 0,
-            n_blocks: 0,
-            flags: 0,
-            direct: [0; 15],
-            single_indirect: 0,
-            double_indirect: 0,
-            triple_indirect: 0,
-            generation: 0,
-            file_acl: 0,
-            dir_acl: 0,
-        }
-    }
-}
-pub const INODE_SIZE: usize = std::mem::size_of::<Inode>();
-pub const ENTRY_PER_BLOCK: usize = BLOCK_SIZE / 4;
\ No newline at end of file
diff --git a/ayafs/src/disk/mod.rs b/ayafs/src/disk/mod.rs
deleted file mode 100644
index 878e832..0000000
--- a/ayafs/src/disk/mod.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-pub mod allocation;
-/// On-disk data structures and logic.
-/// Including bitmaps, inodes and blocks.
-pub mod bitmap;
-pub mod block;
-pub mod inode;
diff --git a/ayafs/src/filesystem/mod.rs b/ayafs/src/filesystem/mod.rs
deleted file mode 100644
index 1eaa8e8..0000000
--- a/ayafs/src/filesystem/mod.rs
+++ /dev/null
@@ -1,2 +0,0 @@
-/// Where upper filesystem calls are implemented.
-pub mod trait_impl;
diff --git a/ayafs/src/filesystem/trait_impl.rs b/ayafs/src/filesystem/trait_impl.rs
deleted file mode 100644
index 1c40b92..0000000
--- a/ayafs/src/filesystem/trait_impl.rs
+++ /dev/null
@@ -1,1247 +0,0 @@
-use crate::block_device::BLOCK_SIZE;
-use crate::disk::block::DataBlock;
-use crate::disk::inode::InodeMode;
-use crate::utils::permissions::{check_access, clear_suid_sgid, get_groups};
-use crate::utils::{from_filetype, from_systime, time_now, to_fileattr, to_filetype};
-use crate::{AyaFS, TTL};
-use fuser::TimeOrNow::{Now, SpecificTime};
-use fuser::{
-    FileType, Filesystem, KernelConfig, ReplyAttr, ReplyData, ReplyDirectory, ReplyEmpty,
-    ReplyEntry, ReplyOpen, ReplyWrite, Request, TimeOrNow,
-};
-use libc::{c_int, EACCES, EBADF, EEXIST, EINVAL, EIO, EISDIR, ENAMETOOLONG, ENOENT, ENOSPC, ENOTDIR, ENOTEMPTY, EPERM, IPOPT_OFFSET, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY, R_OK, S_ISGID, S_ISUID, S_IXGRP, S_IXOTH, S_IXUSR, W_OK, RENAME_NOREPLACE, RENAME_EXCHANGE};
-use log::debug;
-use std::ffi::OsStr;
-use std::os::unix::ffi::OsStrExt;
-use std::path::Path;
-use std::slice;
-use std::time::SystemTime;
-
-impl AyaFS {}
-
-impl Filesystem for AyaFS {
-    fn init(&mut self, _req: &Request<'_>, _config: &mut KernelConfig) -> Result<(), c_int> {
-        debug!("`init()");
-        Ok(())
-    }
-
-    fn destroy(&mut self) {
-        debug!("destroy()");
-        // TODO 写回
-    }
-
-    fn lookup(&mut self, req: &Request<'_>, parent: u64, name: &OsStr, reply: ReplyEntry) {
-        if name.len() > 255 {
-            reply.error(ENAMETOOLONG);
-            return;
-        }
-
-        let parent = parent as usize;
-        if let Some(parent_inode) = self.get_inode(parent) {
-            if check_access(
-                req.uid(),
-                req.gid(),
-                parent_inode.uid,
-                parent_inode.gid,
-                parent_inode.mode,
-                R_OK,
-            ) {
-                let parent_inode = parent_inode.clone();
-                match self.lookup_name(parent, &parent_inode, name) {
-                    Ok((inode_index, _, inode)) => {
-                        let attr = to_fileattr(inode_index as usize, &inode);
-                        reply.entry(&TTL, &attr, 0);
-                    }
-                    Err(err_code) => reply.error(err_code),
-                };
-            } else {
-                reply.error(EACCES);
-            }
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn getattr(&mut self, _req: &Request<'_>, ino: u64, reply: ReplyAttr) {
-        if let Some(inode) = self.get_inode(ino as usize) {
-            reply.attr(&TTL, &to_fileattr(ino as usize, inode));
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn setattr(
-        &mut self,
-        req: &Request<'_>,
-        ino: u64,
-        mode: Option<u32>,
-        uid: Option<u32>,
-        gid: Option<u32>,
-        size: Option<u64>, // 当 setattr 被 ftruncate invoke 时会设置 size
-        atime: Option<TimeOrNow>,
-        mtime: Option<TimeOrNow>,
-        _ctime: Option<SystemTime>,
-        fh: Option<u64>,               // 当 setattr 被 ftruncate invoke 时会提供 fh
-        _crtime: Option<SystemTime>,   // 忽略
-        _chgtime: Option<SystemTime>,  // 忽略
-        _bkuptime: Option<SystemTime>, // 忽略
-        _flags: Option<u32>,           // 忽略
-        reply: ReplyAttr,
-    ) {
-        if let Some(inode) = self.get_inode_mut(ino as usize) {
-            // chmod
-            if let Some(mode) = mode {
-                debug!("chmod on inode {:#x?} mode {:o}", ino, mode);
-                if req.uid() != 0 && req.uid() != inode.uid {
-                    reply.error(EPERM);
-                    return;
-                } // uid == 0 (root) or uid == inode.uid (user itself)
-
-                if req.uid() != 0
-                    && req.gid() != inode.gid
-                    && !get_groups(req.pid()).contains(&inode.gid)
-                {
-                    inode.mode = InodeMode((mode & !S_ISGID) as u16);
-                } else {
-                    inode.mode = InodeMode(mode as u16);
-                }
-
-                inode.ctime = time_now();
-                reply.attr(&TTL, &to_fileattr(ino as usize, inode));
-                return;
-            }
-
-            // chown
-            if uid.is_some() || gid.is_some() {
-                debug!("chown on inode {:#x?} uid {:?} gid {:?}", ino, uid, gid);
-                if let Some(uid) = uid {
-                    // 虽然只有 root 可以 chown 但是 user chown 自己也是不报错的
-                    if req.uid() != 0 && !(uid == inode.uid && uid == req.uid()) {
-                        reply.error(EPERM);
-                        return;
-                    }
-                }
-                if let Some(gid) = gid {
-                    // 只有 root 和 file owner 才可以 chgrp
-                    if req.uid() != 0 && req.uid() != inode.uid {
-                        reply.error(EPERM);
-                        return;
-                    }
-                    // root 可以任意 chgrp, 非 root 只能修改到用户自己所在的组里
-                    if req.gid() != 0 && !get_groups(req.pid()).contains(&gid) {
-                        reply.error(EPERM);
-                        return;
-                    }
-                }
-
-                // 可执行文件要清除 suid & sgid
-                if inode.mode.0 & (S_IXUSR | S_IXGRP | S_IXOTH) as u16 != 0 {
-                    inode.mode = clear_suid_sgid(inode.mode);
-                }
-
-                // chown 要清除 suid
-                if let Some(uid) = uid {
-                    inode.uid = uid;
-                    inode.mode.0 &= !S_ISUID as u16;
-                }
-
-                if let Some(gid) = gid {
-                    inode.gid = gid;
-                    if req.uid() != 0 {
-                        inode.mode.0 &= !S_ISGID as u16;
-                    }
-                }
-                inode.ctime = time_now();
-                reply.attr(&TTL, &to_fileattr(ino as usize, inode));
-                return;
-            }
-
-            // ftruncate
-            if let Some(size) = size {
-                // TODO 当大小减小的时候对应 deallocate 块
-                debug!("ftruncate on inode {:#x?} size {:?}", ino, size);
-                if let Some(file_handle) = fh {
-                    let mut inode = inode.clone();
-                    let (inode_index, _read, write) =
-                        self.file_handle_map.get(&file_handle).unwrap();
-                    assert_eq!(ino as usize, *inode_index);
-                    if !write {
-                        reply.error(EACCES);
-                    } else {
-                        inode.size = size as u32;
-                        reply.attr(&TTL, &to_fileattr(*inode_index, &inode));
-                        self.update_inode(*inode_index, inode);
-                    }
-                } else {
-                    if !check_access(req.uid(), req.gid(), inode.uid, inode.gid, inode.mode, W_OK) {
-                        reply.error(EACCES);
-                    } else {
-                        inode.size = size as u32;
-                        reply.attr(&TTL, &to_fileattr(ino as usize, &inode));
-                    }
-                }
-                return;
-            }
-
-            // time 相关
-            if atime.is_some() || mtime.is_some() {
-                let current_time = time_now();
-                if let Some(atime) = atime {
-                    debug!("utimensat on inode {:#x?}, atime {:?}", ino, atime);
-                    // root 和 user 可以随意修改 atime, 其他用户只能 touch (即 atime == Now)
-                    if req.uid() != 0 && req.uid() != inode.uid && atime != Now {
-                        reply.error(EPERM);
-                        return;
-                    }
-
-                    if req.uid() != 0
-                        && req.uid() != inode.uid
-                        && check_access(
-                            req.uid(),
-                            req.gid(),
-                            inode.uid,
-                            inode.gid,
-                            inode.mode,
-                            R_OK, // atime 来说是 read TODO 对吗
-                        )
-                    {
-                        reply.error(EACCES);
-                        return;
-                    }
-
-                    inode.atime = match atime {
-                        SpecificTime(time) => from_systime(time),
-                        Now => current_time,
-                    };
-                    inode.ctime = current_time;
-                }
-                if let Some(mtime) = mtime {
-                    debug!("utimensat on inode {:#x?}, mtime {:?}", ino, mtime);
-                    // root 和 user 可以随意修改 mtime, 其他用户只能 mtime == Now
-                    if req.uid() != 0 && req.uid() != inode.uid && mtime != Now {
-                        reply.error(EPERM);
-                        return;
-                    }
-
-                    if req.uid() != 0
-                        && req.uid() != inode.uid
-                        && check_access(
-                            req.uid(),
-                            req.gid(),
-                            inode.uid,
-                            inode.gid,
-                            inode.mode,
-                            W_OK, // mtime 来说是 write
-                        )
-                    {
-                        reply.error(EACCES);
-                        return;
-                    }
-
-                    inode.mtime = match mtime {
-                        SpecificTime(time) => from_systime(time),
-                        Now => current_time,
-                    };
-                    inode.ctime = current_time;
-                }
-            }
-            reply.attr(&TTL, &to_fileattr(ino as usize, inode));
-            return;
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    // 这啥语义啊??
-    fn readlink(&mut self, req: &Request<'_>, ino: u64, reply: ReplyData) {
-        debug!("readlink(ino: {})", ino);
-        if let Some(inode) = self.get_inode(ino as usize) {
-            if !inode.is_symlink() {
-                reply.error(ENOENT);
-                return;
-            }
-            if !check_access(req.uid(), req.gid(), inode.uid, inode.gid, inode.mode, R_OK) {
-                reply.error(EACCES);
-                return;
-            }
-            let path_length = inode.size as usize;
-            let mut path = vec![0u8; path_length];
-            if path_length < 60 {
-                debug!(
-                    "symlink path length is {}, reading directly from inode.direct",
-                    path_length
-                );
-                let copy_src = unsafe {
-                    let src = (&inode.direct) as *const u32 as *const u8;
-                    slice::from_raw_parts(src, path_length)
-                };
-                path.as_mut_slice().copy_from_slice(copy_src);
-            } else {
-                debug!(
-                    "symlink path length is {}, using original read",
-                    path_length
-                );
-                let inode = inode.clone();
-                let mut read_ptr = 0usize;
-                while read_ptr < path_length {
-                    let block_index = read_ptr / BLOCK_SIZE;
-                    let offset = read_ptr % BLOCK_SIZE;
-
-                    let read_length_within_block = if BLOCK_SIZE - offset < path_length - read_ptr {
-                        BLOCK_SIZE - offset
-                    } else {
-                        path_length - read_ptr
-                    };
-
-                    if let Some(block) = self.access_block::<DataBlock>(&inode, block_index) {
-                        (&mut path[read_ptr..read_ptr + read_length_within_block]).copy_from_slice(
-                            &block.block.0[offset..offset + read_length_within_block],
-                        );
-                        read_ptr += read_length_within_block;
-                    } else {
-                        reply.error(EIO);
-                        return;
-                    }
-                }
-            }
-            debug!(
-                "readlink path read is {:?}",
-                OsStr::from_bytes(path.as_slice())
-            );
-            reply.data(path.as_slice());
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn mknod(
-        &mut self,
-        req: &Request<'_>,
-        parent: u64,
-        name: &OsStr,
-        mode: u32,
-        _umask: u32, // umask 是用不到的
-        _rdev: u32,  // the device number (only valid if created file is a device)
-        reply: ReplyEntry,
-    ) {
-        debug!(
-            "mknod(parent: {}, name: {:?}, mode: {}, umask: {})",
-            parent, name, mode, _umask
-        );
-
-        let parent = parent as usize;
-        if let Some(parent_inode) = self.get_inode(parent) {
-            if !check_access(
-                req.uid(),
-                req.gid(),
-                parent_inode.uid,
-                parent_inode.gid,
-                parent_inode.mode,
-                W_OK,
-            ) {
-                reply.error(EACCES);
-                return;
-            }
-
-            // parent 不是 IFDIR -> Not a directory
-            if !parent_inode.is_dir() {
-                reply.error(ENOTDIR);
-                return;
-            }
-
-            // 文件名长度超过 255, 返回 filename too long
-            if name.len() > 255 {
-                reply.error(ENAMETOOLONG);
-                return;
-            }
-
-            let mut parent_inode = parent_inode.clone();
-            // 如果已经存在, 返回 already exists
-            if self.lookup_name(parent, &parent_inode, name).is_ok() {
-                reply.error(EEXIST);
-                return;
-            }
-
-            let mode = mode as u16;
-            if let Some((child_inode_index, child_inode)) =
-                self.create_file(mode, req.uid(), req.gid(), 0)
-            {
-                let mode = child_inode.mode;
-                let file_attr = to_fileattr(child_inode_index, child_inode);
-                if let Err(err_code) = self.add_direntry(
-                    parent,
-                    &mut parent_inode,
-                    child_inode_index,
-                    name,
-                    mode.into(),
-                ) {
-                    reply.error(err_code);
-                    return;
-                }
-                self.update_inode(parent, parent_inode); // 前面 clone 了, 这里写回
-                reply.entry(&TTL, &file_attr, 0);
-            } else {
-                // create_inode 失败 -> no enough space
-                reply.error(ENOSPC);
-            }
-        } else {
-            // parent 不存在 -> No such file or directory
-            reply.error(ENOENT);
-        }
-    }
-
-    fn mkdir(
-        &mut self,
-        req: &Request<'_>,
-        parent: u64,
-        name: &OsStr,
-        mode: u32,
-        _umask: u32, // umask 应该也是用不到的
-        reply: ReplyEntry,
-    ) {
-        if let Some(parent_inode) = self.get_inode(parent as usize) {
-            // 无权限创建 -> EACCES
-            if !check_access(
-                req.uid(),
-                req.gid(),
-                parent_inode.uid,
-                parent_inode.gid,
-                parent_inode.mode,
-                W_OK,
-            ) {
-                reply.error(EACCES);
-                return;
-            }
-
-            // parent 不是 IFDIR -> Not a directory
-            if !parent_inode.is_dir() {
-                reply.error(ENOTDIR);
-                return;
-            }
-
-            // 文件名长度超过 255 -> filename too long
-            if name.len() > 255 {
-                reply.error(ENAMETOOLONG);
-                return;
-            }
-
-            let mut parent_inode = parent_inode.clone();
-            // 已经存在 -> File exists
-            if self
-                .lookup_name(parent as usize, &parent_inode, name)
-                .is_ok()
-            {
-                reply.error(EEXIST);
-                return;
-            }
-
-            let mode = mode as u16;
-            if let Some((child_inode_index, child_inode)) =
-                self.create_directory(mode, req.uid(), req.gid(), 0, Some(parent as usize))
-            {
-                let child_inode = child_inode.clone();
-                let file_attr = to_fileattr(child_inode_index, &child_inode);
-                if let Err(err_code) = self.add_direntry(
-                    parent as usize,
-                    &mut parent_inode,
-                    child_inode_index,
-                    name,
-                    child_inode.mode.into(),
-                ) {
-                    reply.error(err_code);
-                    return;
-                }
-                self.update_inode(parent as usize, parent_inode); // 前面 clone 了, 这里写回
-                reply.entry(&TTL, &file_attr, 0);
-            } else {
-                // create_inode 失败 -> no enough space
-                reply.error(ENOSPC);
-            }
-        } else {
-            // parent 不存在 -> No such file or directory
-            reply.error(ENOENT);
-        }
-    }
-
-    fn unlink(&mut self, req: &Request<'_>, parent: u64, name: &OsStr, reply: ReplyEmpty) {
-        debug!("unlink(parent: {:#x?}, name: {:?})", parent, name,);
-        if let Some(parent_inode) = self.get_inode(parent as usize) {
-            // 无权限删除 -> EACCES
-            if !check_access(
-                req.uid(),
-                req.gid(),
-                parent_inode.uid,
-                parent_inode.gid,
-                parent_inode.mode,
-                W_OK,
-            ) {
-                reply.error(EACCES);
-                return;
-            }
-
-            // parent 不是 dir -> ENOTDIR
-            if !parent_inode.is_dir() {
-                reply.error(ENOTDIR);
-                return;
-            }
-
-            // 文件名长度超过 255 -> filename too long
-            if name.len() > 255 {
-                reply.error(ENAMETOOLONG);
-                return;
-            }
-
-            let mut parent_inode = parent_inode.clone();
-            // 不存在 -> No such file or directory
-            if let Ok((inode_index, entry_index, mut inode)) =
-                self.lookup_name(parent as usize, &parent_inode, name)
-            {
-                let inode_index = inode_index as usize;
-
-                match inode.file_type() {
-                    FileType::RegularFile => {
-                        inode.n_links -= 1;
-                        if inode.n_links == 0 {
-                            // n_links == 0 -> 整个 inode 都要删除掉
-                            match self.remove_file(inode_index) {
-                                Ok(flag) => debug!("  unlink {}", flag),
-                                Err(err_code) => {
-                                    reply.error(err_code);
-                                    return;
-                                }
-                            }
-                        } else {
-                            // n_links > 0 -> 只是移除了一个 hard link, 将改动写回
-                            self.update_inode(inode_index, inode);
-                        }
-                    }
-                    FileType::Symlink => {}
-                    FileType::Directory => {
-                        reply.error(EISDIR);
-                        return;
-                    }
-                    _ => {
-                        // Not implemented!
-                        reply.error(EIO);
-                        return;
-                    }
-                }
-
-                // 删除 dir entry
-                if let Err(err_code) =
-                    self.remove_direntry(parent as usize, &mut parent_inode, name, entry_index)
-                {
-                    reply.error(err_code);
-                    return;
-                }
-                reply.ok();
-            } else {
-                reply.error(ENOENT);
-            }
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn rmdir(&mut self, req: &Request<'_>, parent: u64, name: &OsStr, reply: ReplyEmpty) {
-        debug!("rmdir(parent: {:#x?}, name: {:?}", parent, name,);
-        if let Some(parent_inode) = self.get_inode(parent as usize) {
-            // 无权限删除 -> EACCES
-            if !check_access(
-                req.uid(),
-                req.gid(),
-                parent_inode.uid,
-                parent_inode.gid,
-                parent_inode.mode,
-                W_OK,
-            ) {
-                reply.error(EACCES);
-                return;
-            }
-
-            // parent 不是 dir -> ENOTDIR
-            if !parent_inode.is_dir() {
-                reply.error(ENOTDIR);
-                return;
-            }
-
-            // 文件名长度超过 255 -> filename too long
-            if name.len() > 255 {
-                reply.error(ENAMETOOLONG);
-                return;
-            }
-
-            let mut parent_inode = parent_inode.clone();
-            // 不存在 -> No such file or directory
-            if let Ok((inode_index, entry_index, inode)) =
-                self.lookup_name(parent as usize, &parent_inode, name)
-            {
-                let inode_index = inode_index as usize;
-                // 要删除的 entry 是一般文件, 不用 rmdir
-                if inode.is_file() {
-                    reply.error(ENOTDIR);
-                    return;
-                }
-
-                // 一定有 . 和 .. 所以 size == 2 就是空目录
-                // 目录非空 -> ENOTEMPTY
-                if inode.size > 2 {
-                    reply.error(ENOTEMPTY);
-                    return;
-                }
-
-                // directory 没有 hard link, 删了就是删了
-                match self.remove_dir(inode_index) {
-                    Ok(flag) => debug!("  rmdir {}", flag),
-                    Err(err_code) => {
-                        reply.error(err_code);
-                        return;
-                    }
-                }
-
-                // 删除 dir entry
-                if let Err(err_code) =
-                    self.remove_direntry(parent as usize, &mut parent_inode, name, entry_index)
-                {
-                    reply.error(err_code);
-                    return;
-                }
-
-                reply.ok();
-            } else {
-                reply.error(ENOENT);
-            }
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn symlink(
-        &mut self,
-        req: &Request<'_>,
-        parent: u64,
-        link_name: &OsStr,
-        target: &Path,
-        reply: ReplyEntry,
-    ) {
-        debug!(
-            "symlink(parent: {}, name: {:?}, target: {:?})",
-            parent, link_name, target
-        );
-        let parent = parent as usize;
-
-        // let root_inode_index = 1usize;
-        // if let Some(root_inode) = self.get_inode(root_inode_index) {
-        //     let mut curr_inode_index = root_inode_index;
-        //     let mut curr_inode = root_inode.clone();
-        //     for segment in target.iter() {
-        //         match self.lookup_name(curr_inode_index, &curr_inode, segment) {
-        //             Ok((next_inode_index, _, next_inode)) => {
-        //                 curr_inode_index = next_inode_index as usize;
-        //                 curr_inode = next_inode;
-        //             }
-        //             Err(err_code) => {
-        //                 reply.error(err_code);
-        //                 return;
-        //             }
-        //         }
-        //     }
-        // } else {
-        //     reply.error(EIO);
-        //     return;
-        // }
-
-        if let Some(parent_inode) = self.get_inode(parent) {
-            if !check_access(
-                req.uid(),
-                req.gid(),
-                parent_inode.uid,
-                parent_inode.gid,
-                parent_inode.mode,
-                W_OK,
-            ) {
-                reply.error(EACCES);
-                return;
-            }
-
-            if !parent_inode.is_dir() {
-                reply.error(ENOTDIR);
-                return;
-            }
-
-            if link_name.len() > 255 {
-                reply.error(ENAMETOOLONG);
-                return;
-            }
-
-            let target = target.as_os_str();
-            let mut parent_inode = parent_inode.clone();
-            if self.lookup_name(parent, &parent_inode, link_name).is_ok() {
-                reply.error(EEXIST);
-                return;
-            }
-
-            if let Some((child_inode_index, child_inode)) =
-                self.create_symlink(0o777, req.uid(), req.gid(), 0)
-            {
-                let mut child_inode = child_inode.clone();
-                child_inode.size = target.len() as u32;
-                if target.len() < 60 {
-                    debug!("create_symlink: target length < 60, allocating in 'direct' section.");
-                    let target_path = target.as_bytes();
-                    let copy_dst = unsafe {
-                        let dst = (&mut child_inode.direct) as *mut u32 as *mut u8;
-                        slice::from_raw_parts_mut(dst, target_path.len())
-                    };
-                    copy_dst.copy_from_slice(target_path);
-                } else {
-                    debug!("create_symlink: target length >= 60, using original layout.");
-                    let mut write_ptr = 0usize;
-                    while write_ptr < target.len() {
-                        let block_index = write_ptr / BLOCK_SIZE;
-                        let offset = write_ptr % BLOCK_SIZE;
-
-                        let write_length_within_block =
-                            if BLOCK_SIZE - offset < target.len() - write_ptr {
-                                BLOCK_SIZE - offset
-                            } else {
-                                target.len() - write_ptr
-                            };
-
-                        if let Some(block) =
-                            self.access_block_mut::<DataBlock>(&child_inode, block_index)
-                        {
-                            block.block.0[offset..offset + write_length_within_block]
-                                .copy_from_slice(
-                                    &target.as_bytes()
-                                        [write_ptr..write_ptr + write_length_within_block],
-                                );
-                            write_ptr += write_length_within_block;
-                        } else {
-                            if let Some((_block_index, block_index_within_inode)) =
-                                self.allocate_block_for(&mut child_inode)
-                            {
-                                let block = self
-                                    .access_block_mut::<DataBlock>(
-                                        &child_inode,
-                                        block_index_within_inode,
-                                    )
-                                    .unwrap();
-                                block.block.0[offset..offset + write_length_within_block]
-                                    .copy_from_slice(
-                                        &target.as_bytes()
-                                            [write_ptr..write_ptr + write_length_within_block],
-                                    );
-                                write_ptr += write_length_within_block;
-                            } else {
-                                reply.error(ENOSPC);
-                                return;
-                            }
-                        }
-                    }
-                }
-
-                let file_attr = to_fileattr(child_inode_index, &child_inode);
-                self.update_inode(child_inode_index, child_inode);
-
-                if let Err(err_code) = self.add_direntry(
-                    parent,
-                    &mut parent_inode,
-                    child_inode_index,
-                    link_name,
-                    from_filetype(FileType::Symlink),
-                ) {
-                    reply.error(err_code);
-                    return;
-                }
-                self.update_inode(parent, parent_inode);
-                reply.entry(&TTL, &file_attr, 0);
-            } else {
-                reply.error(ENOSPC);
-            }
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn rename(
-        &mut self,
-        req: &Request<'_>,
-        parent: u64,
-        name: &OsStr,
-        new_parent: u64,
-        new_name: &OsStr,
-        flags: u32,
-        reply: ReplyEmpty,
-    ) {
-        debug!(
-            "rename(parent: {}, name: {:?}, new_parent: {}, new_name: {:?})",
-            parent, name, new_parent, new_name
-        );
-
-        let parent = parent as usize;
-        let new_parent = new_parent as usize;
-        if let Some(parent_inode) = self.get_inode(parent) {
-            if !check_access(
-                req.uid(),
-                req.gid(),
-                parent_inode.uid,
-                parent_inode.gid,
-                parent_inode.mode,
-                R_OK,
-            ) {
-                reply.error(EACCES);
-                return;
-            }
-
-            if name.len() > 255 {
-                reply.error(ENAMETOOLONG);
-                return;
-            }
-
-            let mut parent_inode = parent_inode.clone();
-            match self.lookup_name(parent, &parent_inode, name) {
-                Ok((inode_index, entry_index, inode)) => {
-                    if let Some(new_parent_inode) = self.get_inode(new_parent) {
-                        if !check_access(
-                            req.uid(),
-                            req.gid(),
-                            new_parent_inode.uid,
-                            new_parent_inode.gid,
-                            new_parent_inode.mode,
-                            W_OK,
-                        ) {
-                            reply.error(EACCES);
-                            return;
-                        }
-                        if new_name.len() > 255 {
-                            reply.error(ENAMETOOLONG);
-                            return;
-                        }
-
-                        let mut new_parent_inode = new_parent_inode.clone();
-                        match self.lookup_name(new_parent, &new_parent_inode, new_name) {
-                            Ok((new_inode_index, new_entry_index, new_inode)) => {
-                                // 新文件存在
-                                if flags & RENAME_NOREPLACE != 0 { // 指定 noreplace 之后不允许覆盖文件
-                                    reply.error(EEXIST);
-                                    return;
-                                }
-                                if flags & RENAME_EXCHANGE != 0 { // 交换两个文件
-                                    if let Err(err_code) = self.exchange_direntry(
-                                        parent,
-                                        &mut parent_inode,
-                                        name,
-                                        new_parent,
-                                        &mut new_parent_inode,
-                                        new_name
-                                    ) {
-                                        reply.error(err_code);
-                                        return;
-                                    }
-                                } else { // 用新文件替换旧文件
-                                    let dir_entry = self.get_direntry_by_name(parent, &parent_inode, name)
-                                        .unwrap();
-                                    if let Err(err_code) = self.remove_direntry(parent, &mut parent_inode, name, entry_index) {
-                                        reply.error(err_code);
-                                        return;
-                                    }
-                                    if let Err(err_code) = self.remove_direntry(new_parent, &mut new_parent_inode, new_name, new_entry_index) {
-                                        reply.error(err_code);
-                                        return;
-                                    }
-                                    if let Err(err_code) = self.add_direntry_2(new_parent, &mut new_parent_inode, new_name, dir_entry) {
-                                        reply.error(err_code);
-                                        return;
-                                    }
-                                }
-                                reply.ok();
-                            },
-                            Err(ENOENT) => { // 新文件不存在, 删除旧的创建新的
-                                let dir_entry = self.get_direntry_by_name(parent, &parent_inode, name)
-                                    .unwrap();
-                                if let Err(err_code) = self.remove_direntry(parent, &mut parent_inode, name, entry_index) {
-                                    reply.error(err_code);
-                                    return;
-                                }
-                                if let Err(err_code) = self.add_direntry_2(new_parent, &mut new_parent_inode, new_name, dir_entry) {
-                                    reply.error(err_code);
-                                    return;
-                                }
-                                reply.ok();
-                            },
-                            Err(err_code) => {
-                                // 其他 Err code
-                                reply.error(err_code);
-                                return;
-                            }
-                        }
-                    } else {
-                        reply.error(ENOENT);
-                    }
-                },
-                Err(err_code) => {
-                    reply.error(err_code);
-                    return;
-                }
-            }
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn open(&mut self, req: &Request<'_>, ino: u64, flags: i32, reply: ReplyOpen) {
-        debug!("open(ino: {:#x?}, flags: {:#x?})", ino, flags);
-        let (access_mask, read, write) = match flags & O_ACCMODE {
-            O_RDONLY => {
-                // Behavior is undefined, but most filesystems return EACCES
-                if flags & libc::O_TRUNC != 0 {
-                    reply.error(EACCES);
-                    return;
-                }
-                (R_OK, true, false)
-            }
-            O_WRONLY => (W_OK, false, true),
-            O_RDWR => (R_OK | W_OK, true, true),
-            _ => {
-                // flag 非法
-                reply.error(EINVAL);
-                return;
-            }
-        };
-
-        match self.get_inode(ino as usize) {
-            Some(inode) => {
-                if !check_access(
-                    req.uid(),
-                    req.gid(),
-                    inode.uid,
-                    inode.gid,
-                    inode.mode,
-                    access_mask,
-                ) {
-                    reply.error(EACCES);
-                    return;
-                }
-                let fd = self.allocate_file_descriptor(ino as usize, read, write);
-                reply.opened(fd, 0);
-            }
-            None => {
-                reply.error(ENOENT);
-            }
-        }
-    }
-
-    // read [offset, offset + size)
-    // - EOF < offset + size -> return EOF - offset
-    // - EOF > offset + size -> return size
-    fn read(
-        &mut self,
-        req: &Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        size: u32,
-        _flags: i32,
-        _lock_owner: Option<u64>, // 用不到!
-        reply: ReplyData,
-    ) {
-        assert_eq!(self.file_handle_map.get(&fh).unwrap().0, ino as usize);
-        if let Some(inode) = self.get_inode(ino as usize) {
-            if inode.is_dir() {
-                reply.error(EISDIR);
-                return;
-            }
-            if !check_access(req.uid(), req.gid(), inode.uid, inode.gid, inode.mode, R_OK) {
-                reply.error(EACCES);
-                return;
-            }
-            debug!("reading inode {:#x} (offset {} size {})", ino, offset, size);
-
-            if offset as u32 >= inode.size {
-                // offset 在 EOF 后面, 直接返回一个 0 长度的空 buffer
-                reply.data(&Vec::new());
-                return;
-            }
-
-            // let read_length = size.min(inode.size.saturating_sub(offset as u32)) as usize;
-            // 这和下面那个是等同的但是不利于让人看懂……
-            let read_length = if offset as u32 + size <= inode.size {
-                size // 没有越过 EOF, 读取 size 个 byte
-            } else {
-                inode.size - offset as u32 // 越过了 EOF, 读取 inode.size - offset 个 byte
-            } as usize;
-
-            let mut read_buffer = vec![0u8; read_length];
-            let mut read_ptr = 0usize;
-
-            let inode = inode.clone();
-
-            while read_ptr < read_length {
-                let current_point = offset as usize + read_ptr;
-                let current_block_index = current_point / BLOCK_SIZE;
-                let current_offset = current_point % BLOCK_SIZE;
-
-                let read_length_within_block =
-                    if BLOCK_SIZE - current_offset < read_length - read_ptr {
-                        BLOCK_SIZE - current_offset // 可以读到 block 最后
-                    } else {
-                        read_length - read_ptr // 读到中途会停下来
-                    };
-
-                if let Some(block) = self.access_block::<DataBlock>(&inode, current_block_index) {
-                    (&mut read_buffer[read_ptr..read_ptr + read_length_within_block])
-                        .copy_from_slice(
-                            &block.block.0
-                                [current_offset..current_offset + read_length_within_block],
-                        );
-                    read_ptr += read_length_within_block;
-                } else {
-                    reply.error(EIO);
-                    return;
-                }
-            }
-
-            reply.data(&read_buffer);
-        }
-    }
-
-    // 写了多少就返回多少
-    fn write(
-        &mut self,
-        req: &Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        data: &[u8],
-        _write_flags: u32,
-        _flags: i32,
-        _lock_owner: Option<u64>,
-        reply: ReplyWrite,
-    ) {
-        assert_eq!(self.file_handle_map.get(&fh).unwrap().0, ino as usize);
-        if let Some(inode) = self.get_inode(ino as usize) {
-            if inode.is_dir() {
-                reply.error(EISDIR);
-                return;
-            }
-            if !check_access(req.uid(), req.gid(), inode.uid, inode.gid, inode.mode, W_OK) {
-                reply.error(EACCES);
-                return;
-            }
-            debug!(
-                "writing inode {:#x} (offset {} size {})",
-                ino,
-                offset,
-                data.len()
-            );
-            let write_length = data.len();
-            let mut write_ptr = 0usize;
-
-            let mut inode = inode.clone();
-
-            while write_ptr < write_length {
-                let current_point = offset as usize + write_ptr;
-                let current_block_index = current_point / BLOCK_SIZE;
-                let current_offset = current_point % BLOCK_SIZE;
-
-                let write_length_within_block =
-                    if BLOCK_SIZE - current_offset < write_length - write_ptr {
-                        BLOCK_SIZE - current_offset // 可以写满 block
-                    } else {
-                        write_length - write_ptr // 写完 buffer 就停下来
-                    };
-
-                // 当前块已分配, 直接往里写
-                if let Some(block) = self.access_block_mut::<DataBlock>(&inode, current_block_index)
-                {
-                    debug!(
-                        "writing {} bytes in block {} within inode",
-                        write_length_within_block, current_block_index
-                    );
-                    (block.block.0[current_offset..current_offset + write_length_within_block])
-                        .copy_from_slice(&data[write_ptr..write_ptr + write_length_within_block]);
-                    write_ptr += write_length_within_block;
-                } else {
-                    // 当前块未分配，尝试分配
-                    if let Some((block_index, block_index_within_inode)) =
-                        self.allocate_block_for(&mut inode)
-                    {
-                        debug!("writing {} bytes in allocated block {} within inode, block index is {}", write_length_within_block, block_index_within_inode, block_index);
-                        // 能分配, 往里写
-                        let block = self
-                            .access_block_mut::<DataBlock>(&inode, block_index_within_inode)
-                            .unwrap();
-                        (block.block.0[current_offset..current_offset + write_length_within_block])
-                            .copy_from_slice(
-                                &data[write_ptr..write_ptr + write_length_within_block],
-                            );
-                        write_ptr += write_length_within_block;
-                    } else {
-                        // 分配不了, 没空间了
-                        break;
-                    }
-                }
-            }
-
-            inode.size = inode.size.max(offset as u32 + write_length as u32);
-            self.update_inode(ino as usize, inode);
-            reply.written(write_length as u32);
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn release(
-        &mut self,
-        _req: &Request<'_>,
-        ino: u64,
-        fh: u64,
-        _flags: i32,
-        _lock_owner: Option<u64>,
-        _flush: bool,
-        reply: ReplyEmpty,
-    ) {
-        debug!("release(ino: {:#x?}, fh: {}", ino, fh);
-        if self.file_handle_map.contains_key(&fh) {
-            self.file_handle_map.remove(&fh);
-            reply.ok();
-        } else {
-            reply.error(EBADF);
-        }
-    }
-
-    fn opendir(&mut self, req: &Request<'_>, ino: u64, flags: i32, reply: ReplyOpen) {
-        debug!("opendir(ino: {:#x?}, flags: {:#x?})", ino, flags);
-        let (access_mask, read, write) = match flags & O_ACCMODE {
-            O_RDONLY => {
-                // Behavior is undefined, but most filesystems return EACCES
-                if flags & libc::O_TRUNC != 0 {
-                    reply.error(EACCES);
-                    return;
-                }
-                (R_OK, true, false)
-            }
-            O_WRONLY => (W_OK, false, true),
-            O_RDWR => (R_OK | W_OK, true, true),
-            _ => {
-                // flag 非法
-                reply.error(EINVAL);
-                return;
-            }
-        };
-
-        match self.get_inode(ino as usize) {
-            Some(inode) => {
-                if !check_access(
-                    req.uid(),
-                    req.gid(),
-                    inode.uid,
-                    inode.gid,
-                    inode.mode,
-                    access_mask,
-                ) {
-                    reply.error(EACCES);
-                    return;
-                }
-                let fd = self.allocate_file_descriptor(ino as usize, read, write);
-                reply.opened(fd, 0);
-            }
-            None => {
-                reply.error(ENOENT);
-            }
-        }
-    }
-
-    fn readdir(
-        &mut self,
-        req: &Request<'_>,
-        ino: u64,
-        fh: u64, // 如果 invoke 它的 opendir 里有指定 fh, 那么这里会收到 fh 参数
-        offset: i64,
-        mut reply: ReplyDirectory,
-    ) {
-        assert_eq!(self.file_handle_map.get(&fh).unwrap().0, ino as usize);
-        if let Some(inode) = self.get_inode(ino as usize) {
-            if !inode.is_dir() {
-                reply.error(ENOTDIR);
-                return;
-            }
-
-            if !check_access(req.uid(), req.gid(), inode.uid, inode.gid, inode.mode, R_OK) {
-                reply.error(EACCES);
-                return;
-            }
-
-            debug!(
-                "reading dir entries from inode {:#x} with offset {}",
-                ino, offset
-            );
-            let inode = inode.clone();
-
-            self.load_direntry_map(ino as usize, &inode).unwrap();
-            for (entry_index, (name, dir_entry)) in self
-                .dir_entry_map
-                .get(&(ino as usize))
-                .unwrap()
-                .iter()
-                .enumerate()
-                .skip(offset as usize)
-            {
-                debug!(
-                    "  entry {} from inode {:#x} with name {:?}",
-                    entry_index, dir_entry.inode, name
-                );
-                if reply.add(
-                    dir_entry.inode as u64,
-                    entry_index as i64 + 1,
-                    to_filetype(dir_entry.file_type).expect("not 0x0!"),
-                    name,
-                ) {
-                    break;
-                }
-            }
-
-            reply.ok();
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-
-    fn releasedir(
-        &mut self,
-        _req: &Request<'_>,
-        ino: u64,
-        fh: u64,
-        _flags: i32,
-        reply: ReplyEmpty,
-    ) {
-        debug!("releasedir(ino: {:#x?}, fh: {}", ino, fh);
-        if self.file_handle_map.contains_key(&fh) {
-            self.file_handle_map.remove(&fh);
-            reply.ok();
-        } else {
-            reply.error(EBADF);
-        }
-    }
-
-    fn access(&mut self, req: &Request<'_>, ino: u64, mask: i32, reply: ReplyEmpty) {
-        // mask:
-        // - 要么是 libc::F_OK (aka 0), 检查文件是否存在
-        // - 要么是 libc::R_OK,libc::W_OK,libc::X_OK (aka 4/2/1) 构成的 bitmask, 检查是否有对应权限
-        debug!("Filesystem::access(ino: {}, mask: {})", ino, mask);
-
-        if let Some(inode) = self.get_inode(ino as usize) {
-            if mask == libc::F_OK // 只要检查是否存在
-                || check_access(req.uid(), req.gid(), inode.uid, inode.gid, inode.mode, mask)
-            // 需要检查 rwx 权限
-            {
-                reply.ok();
-            } else {
-                reply.error(EACCES);
-            }
-        } else {
-            reply.error(ENOENT);
-        }
-    }
-}
diff --git a/ayafs/src/main.rs b/ayafs/src/main.rs
deleted file mode 100644
index db4a017..0000000
--- a/ayafs/src/main.rs
+++ /dev/null
@@ -1,171 +0,0 @@
-mod block_device;
-mod disk;
-mod filesystem;
-mod memory;
-mod tests;
-mod utils;
-
-use clap::Parser;
-use fuser::MountOption;
-use indexmap::IndexMap;
-use log::{debug, LevelFilter};
-use lru::LruCache;
-use std::collections::HashMap;
-use std::ffi::OsString;
-use std::num::NonZeroUsize;
-use std::path::PathBuf;
-use std::sync::atomic::AtomicU64;
-use std::sync::Arc;
-use std::time::Duration;
-
-use crate::disk::block::{DirectoryEntry, InodeBlock};
-use crate::memory::cached_block::BlockCache;
-use block_device::{memory_disk::MemoryDisk, BlockDevice, BLOCK_SIZE};
-use disk::bitmap::Bitmap;
-use disk::block::DataBlock;
-use disk::inode::INODE_SIZE;
-use users::{get_current_gid, get_current_uid};
-use crate::block_device::disk::Disk;
-
-#[derive(Parser, Debug)]
-#[command(author, version, about)]
-struct Args {
-    mount_point: Option<String>,
-    #[arg(short, action = clap::ArgAction::Count)]
-    verbosity: u8,
-    #[arg(long)]
-    auto_unmount: bool,
-    #[arg(long)]
-    allow_root: bool,
-}
-
-const TTL: Duration = Duration::new(0, 0);
-const INODE_PER_BLOCK: usize = BLOCK_SIZE / INODE_SIZE;
-
-/// The design of MyFS is rather simple:
-/// +-------------------+
-/// | Super Block       |
-/// +-------------------+
-/// | Inode Bitmap      |
-/// +-------------------+
-/// | ...               |
-/// +-------------------+
-/// | Data Block Bitmap |
-/// +-------------------+
-/// | ...               |
-/// +-------------------+
-/// | Inode Block       |
-/// +-------------------+
-/// | ...               |
-/// +-------------------+
-/// | Data Block        |
-/// +-------------------+
-/// With each block 4KiB, each Inode entry 128B
-
-#[repr(C)]
-struct AyaFS {
-    device: Arc<dyn BlockDevice>,
-    data_bitmap: Bitmap,
-    inode_bitmap: Bitmap,
-    inode_start_block: usize,
-    data_start_block: usize,
-
-    next_file_handle: AtomicU64,
-    // file descriptor -> (inode index, read, write)
-    file_handle_map: HashMap<u64, (usize, bool, bool)>,
-
-    // inode index -> (index aware) hashmap that maps dir entry name to inode index
-    dir_entry_map: LruCache<usize, IndexMap<OsString, DirectoryEntry>>,
-
-    cached_inodes: BlockCache<InodeBlock>,
-    cached_blocks: BlockCache<DataBlock>,
-}
-
-impl AyaFS {
-    fn new(device: Arc<dyn BlockDevice>, total_block_number: usize) -> Self {
-        let max_inode_number: usize = 16384; // TODO: remove hard-coded magic number
-        let inode_block_number = max_inode_number / INODE_PER_BLOCK; // == 128
-        let inode_bitmap_block_number = (inode_block_number + BLOCK_SIZE - 1) / BLOCK_SIZE;
-
-        let blocks_remaining =
-            total_block_number - inode_block_number - inode_bitmap_block_number - 1;
-        // let number of data blocks be x, the remaining block number be C,
-        // the corresponding data bitmap length should be ceil(x / BLK_SIZE),
-        // thus we have BLK_SIZE * (C-1) / (BLK_SIZE+1) <= x <= BLK_SIZE * C / (BLK_SIZE+1)
-        // the difference of the two bounds is less than 1,
-        // meaning only 1 integer could be in between.
-        // Thus we have x = floor(BLK_SIZE * C / (BLK_SIZE + 1))
-        let data_block_number = BLOCK_SIZE * blocks_remaining / (BLOCK_SIZE + 1);
-        let data_bitmap_block_number = blocks_remaining - data_block_number;
-        debug!("data_bitmap_block_number: {}", data_bitmap_block_number);
-        debug!("inode_bitmap_block_number: {}", inode_bitmap_block_number);
-        debug!("inode_block_number:  {}", inode_block_number);
-        debug!("data_block_number:  {}", data_block_number);
-        debug!(
-            "sum:  {}",
-            1 + data_bitmap_block_number
-                + inode_bitmap_block_number
-                + inode_block_number
-                + data_block_number
-        );
-
-        let mut data_bitmap = Bitmap::new(1, data_bitmap_block_number, device.clone());
-        let _ = data_bitmap.allocate().unwrap(); // data block 0 is not usable
-        let mut inode_bitmap = Bitmap::new(
-            data_bitmap_block_number + 1,
-            inode_bitmap_block_number,
-            device.clone(),
-        );
-        let _ = inode_bitmap.allocate().unwrap(); // inode block 0 is not usable
-
-        let mut fs = Self {
-            device: device.clone(),
-            data_bitmap,
-            inode_bitmap,
-            inode_start_block: data_bitmap_block_number + inode_bitmap_block_number + 1,
-            data_start_block: data_bitmap_block_number
-                + inode_bitmap_block_number
-                + inode_block_number
-                + 1,
-
-            next_file_handle: AtomicU64::new(3), // 0,1,2 are stdin, stdout and stderr
-            file_handle_map: HashMap::new(),
-
-            dir_entry_map: LruCache::new(NonZeroUsize::new(1024).unwrap()),
-
-            cached_inodes: BlockCache::new(device.clone(), 1024),
-            cached_blocks: BlockCache::new(device.clone(), 8192),
-        };
-
-        fs.create_directory(0o755, get_current_uid(), get_current_gid(), 0, None);
-
-        fs
-    }
-}
-
-fn main() {
-    let args = Args::parse();
-    let mount_point = args.mount_point.unwrap();
-    let verbosity = args.verbosity;
-    let log_level = match verbosity {
-        0 => LevelFilter::Error,
-        1 => LevelFilter::Warn,
-        2 => LevelFilter::Info,
-        3 => LevelFilter::Debug,
-        _ => LevelFilter::Trace,
-    };
-    env_logger::builder()
-        .filter_level(log_level)
-        .init();
-    let options = vec![
-        // MountOption::RO,
-        MountOption::FSName("hello".to_string()),
-        MountOption::AutoUnmount,
-        MountOption::AllowRoot,
-    ];
-    let disk = Arc::new(Disk::new(PathBuf::from("/dev/nvme0n1p4")));
-    // let disk = Arc::new(MemoryDisk::new(16384));
-    let filesystem = AyaFS::new(disk, 7864320);
-
-    fuser::mount2(filesystem, mount_point, &options).unwrap();
-}
diff --git a/ayafs/src/memory/cached_block.rs b/ayafs/src/memory/cached_block.rs
deleted file mode 100644
index c3d0338..0000000
--- a/ayafs/src/memory/cached_block.rs
+++ /dev/null
@@ -1,180 +0,0 @@
-use crate::block_device::{BlockDevice, BLOCK_SIZE};
-use crate::disk::block::Block;
-use crate::AyaFS;
-use lru::LruCache;
-use std::num::NonZeroUsize;
-use std::sync::Arc;
-
-#[derive(Clone)]
-pub struct CachedBlock<T: Block> {
-    pub block: T,
-    pub index: usize,
-    pub dirty: bool,
-}
-
-pub fn convert_mut<U: Block, T: Block>(input_block: &mut CachedBlock<U>) -> &mut CachedBlock<T> {
-    let ptr = input_block as *const CachedBlock<U> as *mut u8;
-    let block = ptr.cast::<CachedBlock<T>>();
-    unsafe { &mut *block }
-}
-
-pub fn convert<U: Block, T: Block>(input_block: &CachedBlock<U>) -> &CachedBlock<T> {
-    let ptr = input_block as *const CachedBlock<U> as *mut u8;
-    let block = ptr.cast::<CachedBlock<T>>();
-    unsafe { &*block }
-}
-
-pub(crate) struct BlockCache<T: Block> {
-    device: Arc<dyn BlockDevice>,
-    cache: LruCache<usize, CachedBlock<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 {
-        if self.cache.contains(&index) == false {
-            let mut buffer = [0u8; BLOCK_SIZE];
-            self.device.read(index, &mut buffer);
-            let block: T = unsafe { std::mem::transmute_copy(&buffer) };
-            let cached_block = CachedBlock {
-                block,
-                index,
-                dirty: false,
-            };
-            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 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);
-                }
-            }
-        }
-        true
-    }
-
-    /// 从 LRU cache 里获取一个 block 的引用, 如果没有在 cache 中会加载.
-    /// 这个函数不应该返回 None
-    pub(crate) fn get_block<U: Block>(&mut self, index: usize) -> Option<&CachedBlock<U>> {
-        if !self.cache.contains(&index) {
-            self.load_block(index);
-        }
-        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.
-    /// 这个函数不应该返回 None
-    pub(crate) fn get_block_mut<U: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<U>> {
-        if !self.cache.contains(&index) {
-            self.load_block(index);
-        }
-        self.cache.get_mut(&index).map(|block| {
-            block.dirty = true;
-            convert_mut::<T, U>(block)
-        })
-    }
-
-    /// 向 LRU cache 中插入一个全新初始化的 block
-    /// 这个 block 全 0, 而且是 dirty 的, 即使被挤出去也会触发一次落盘
-    pub(crate) fn init_block(&mut self, index: usize) {
-        let allocated_block = CachedBlock {
-            block: T::default(),
-            index,
-            dirty: true,
-        };
-        if let Some((old_index, old_block)) = self.cache.push(index, allocated_block) {
-            if old_block.dirty {
-                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);
-            }
-        }
-    }
-
-    #[allow(unused)]
-    /// 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>)
-    }
-
-    #[allow(unused)]
-    /// 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 mut data_block = convert::<U, T>(&block).clone();
-            data_block.dirty = true; // TODO 需要把显式写回的都标记为 dirty 吗
-            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 init_block(&mut self, index: usize) {
-        self.cached_blocks.init_block(index);
-    }
-
-    pub(crate) fn get_block<T: Block>(&mut self, index: usize) -> Option<&CachedBlock<T>> {
-        if self.data_bitmap.query(index) {
-            Some(self.cached_blocks.get_block::<T>(index).unwrap())
-        } else {
-            self.cached_blocks.pop(&index);
-            None
-        }
-        // self.data_bitmap
-        //     .query(index)
-        //     .then(|| self.cached_blocks.get_block::<T>(index).unwrap())
-        // 返回 None 当且仅当 data_bitmap 中这个 block 为 invalid
-    }
-
-    pub(crate) fn get_block_mut<T: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<T>> {
-        if self.data_bitmap.query(index) {
-            Some(self.cached_blocks.get_block_mut::<T>(index).unwrap())
-        } else {
-            self.cached_blocks.pop(&index);
-            None
-        }
-        // self.data_bitmap
-        //     .query(index)
-        //     .then(|| self.cached_blocks.get_block_mut::<T>(index).unwrap())
-        // 返回 None 当且仅当 data_bitmap 中这个 block 为 invalid
-    }
-
-    #[allow(unused)]
-    pub(crate) fn peek_block<T: Block>(&self, index: usize) -> Option<&CachedBlock<T>> {
-        self.data_bitmap
-            .query(index)
-            .then(|| self.cached_blocks.peek_block::<T>(index).unwrap())
-        // 返回 None 当且仅当 data_bitmap 中这个 block 为 invalid
-    }
-
-    #[allow(unused)]
-    pub(crate) fn peek_block_mut<T: Block>(&mut self, index: usize) -> Option<&mut CachedBlock<T>> {
-        self.data_bitmap
-            .query(index)
-            .then(|| self.cached_blocks.peek_block_mut::<T>(index).unwrap())
-        // 返回 None 当且仅当 data_bitmap 中这个 block 为 invalid
-    }
-
-    pub(crate) fn update_block<T: Block>(&mut self, block: CachedBlock<T>) -> bool {
-        self.cached_blocks.update_block(block)
-    }
-}
diff --git a/ayafs/src/memory/cached_inode.rs b/ayafs/src/memory/cached_inode.rs
deleted file mode 100644
index 2f26dde..0000000
--- a/ayafs/src/memory/cached_inode.rs
+++ /dev/null
@@ -1,178 +0,0 @@
-use crate::disk::block::InodeBlock;
-use crate::disk::inode::{Inode, INODE_SIZE};
-use crate::{utils, AyaFS};
-use and_then_some::BoolExt;
-use fuser::FileType;
-use libc::{c_int, EIO, EISDIR, ENOENT, ENOTDIR, ENOTEMPTY};
-
-impl AyaFS {
-    pub(crate) fn create_file(
-        &mut self,
-        permissions: u16,
-        uid: u32,
-        gid: u32,
-        flags: u32,
-    ) -> Option<(usize, &Inode)> {
-        self.inode_bitmap.allocate().map(|inode_index| {
-            self.get_inode_mut(inode_index).map(|inode| {
-                *inode = Inode::file(permissions, uid, gid, utils::time_now(), flags, 0, 0, 0);
-            });
-            (inode_index, self.get_inode(inode_index).unwrap())
-        })
-    }
-
-    pub(crate) fn create_symlink(
-        &mut self,
-        permissions: u16,
-        uid: u32,
-        gid: u32,
-        flags: u32,
-    ) -> Option<(usize, &Inode)> {
-        self.inode_bitmap.allocate().map(|inode_index| {
-            self.get_inode_mut(inode_index).map(|inode| {
-                *inode = Inode::symlink(permissions, uid, gid, utils::time_now(), flags, 0, 0, 0);
-            });
-            (inode_index, self.get_inode(inode_index).unwrap())
-        })
-    }
-
-    /// 根目录的 parent_inode_number 传入 None, 会直接以自己作为 .. 的 inode number
-    pub(crate) fn create_directory(
-        &mut self,
-        permissions: u16,
-        uid: u32,
-        gid: u32,
-        flags: u32,
-        parent_inode_number: Option<usize>,
-    ) -> Option<(usize, &Inode)> {
-        self.inode_bitmap.allocate().map(|inode_index| {
-            // 创建 Inode
-            let mut new_inode =
-                Inode::directory(permissions, uid, gid, utils::time_now(), flags, 0, 0, 0);
-            self.init_direntry_map(inode_index);
-            self.add_direntry(inode_index, &mut new_inode, inode_index, ".", 0x2)
-                .unwrap();
-            self.add_direntry(
-                inode_index,
-                &mut new_inode,
-                parent_inode_number.unwrap_or(inode_index),
-                "..",
-                0x2,
-            )
-            .unwrap();
-            // 把 inode 放到指定位置
-            self.get_inode_mut(inode_index).map(|inode| {
-                *inode = new_inode;
-            });
-
-            (inode_index, self.get_inode(inode_index).unwrap())
-        })
-    }
-
-    pub(crate) fn remove_file(&mut self, inode_index: usize) -> Result<bool, c_int> {
-        if self.inode_bitmap.query(inode_index) {
-            let (block_index, offset) = self.locate_inode(inode_index);
-            if let Some(cached_block) = self.cached_inodes.get_block::<InodeBlock>(block_index) {
-                let inode = cached_block.block.inodes[offset / INODE_SIZE].clone();
-                match inode.file_type() {
-                    FileType::RegularFile => self.deallocate_all_blocks_for(&inode).unwrap(),
-                    FileType::Symlink => {
-                        if inode.size >= 60 {
-                            self.deallocate_all_blocks_for(&inode).unwrap();
-                        }
-                    }
-                    FileType::Directory => return Err(EISDIR),
-                    _ => return Err(EIO),
-                }
-            }
-            self.inode_bitmap.deallocate(inode_index);
-            Ok(true)
-        } else {
-            Err(ENOENT)
-        }
-    }
-
-    // 要删除的 inode 一定得是空的
-    pub(crate) fn remove_dir(&mut self, inode_index: usize) -> Result<bool, c_int> {
-        if self.inode_bitmap.query(inode_index) {
-            let (block_index, offset) = self.locate_inode(inode_index);
-            if let Some(cached_block) = self.cached_inodes.get_block::<InodeBlock>(block_index) {
-                let inode = &cached_block.block.inodes[offset / INODE_SIZE].clone();
-                if !inode.is_dir() {
-                    // 不是 dir -> ENOTDIR
-                    return Err(ENOTDIR);
-                }
-                if inode.size > 2 {
-                    // 有 . 和 .. 以外的 entry -> ENOTEMPTY
-                    return Err(ENOTEMPTY);
-                }
-                // 销毁 inode 里的所有 block
-                self.deallocate_all_blocks_for(inode).unwrap();
-            }
-            // 销毁 inode
-            self.inode_bitmap.deallocate(inode_index);
-            Ok(true)
-        } else {
-            Err(ENOENT)
-        }
-    }
-
-    pub(crate) fn update_inode(&mut self, inode_index: usize, inode: Inode) -> bool {
-        if self.inode_bitmap.query(inode_index) {
-            let (block_index, offset) = self.locate_inode(inode_index);
-            if let Some(cached_block) = self.cached_inodes.get_block_mut::<InodeBlock>(block_index)
-            {
-                cached_block.block.inodes[offset / INODE_SIZE] = inode;
-            }
-            true
-        } else {
-            false
-        }
-    }
-
-    pub(crate) fn get_inode(&mut self, inode_index: usize) -> Option<&Inode> {
-        self.inode_bitmap.query(inode_index).and_then(|| {
-            let (block_index, offset) = self.locate_inode(inode_index);
-            // debug!("get_inode(inode_index: {}) -> block_index: {}, offset: {}", inode_index, block_index, offset);
-            self.cached_inodes
-                .get_block::<InodeBlock>(block_index)
-                .map(|cached_block| &cached_block.block.inodes[offset / INODE_SIZE])
-        })
-    }
-
-    pub(crate) fn get_inode_mut(&mut self, inode_index: usize) -> Option<&mut Inode> {
-        self.inode_bitmap.query(inode_index).and_then(|| {
-            let (block_index, offset) = self.locate_inode(inode_index);
-            // debug!("get_inode_mut(inode_index: {}) -> block_index: {}, offset: {}", inode_index, block_index, offset);
-            self.cached_inodes
-                .get_block_mut::<InodeBlock>(block_index)
-                .map(|cached_block| {
-                    cached_block.dirty = true; // 保守一些, 只要返回了 &mut Inode 这个页一定标记为脏
-                    &mut cached_block.block.inodes[offset / INODE_SIZE]
-                })
-        })
-    }
-
-    #[allow(unused)]
-    pub(crate) fn peek_inode(&self, inode_index: usize) -> Option<&Inode> {
-        self.inode_bitmap.query(inode_index).and_then(|| {
-            let (block_index, offset) = self.locate_inode(inode_index);
-            self.cached_inodes
-                .peek_block::<InodeBlock>(block_index)
-                .map(|cached_block| &cached_block.block.inodes[offset / INODE_SIZE])
-        })
-    }
-
-    #[allow(unused)]
-    pub(crate) fn peek_inode_mut(&mut self, inode_index: usize) -> Option<&mut Inode> {
-        self.inode_bitmap.query(inode_index).and_then(|| {
-            let (block_index, offset) = self.locate_inode(inode_index);
-            self.cached_inodes
-                .peek_block_mut::<InodeBlock>(block_index)
-                .map(|cached_block| {
-                    cached_block.dirty = true; // 保守一些, 只要返回了 &mut Inode 这个页一定标记为脏
-                    &mut cached_block.block.inodes[offset / INODE_SIZE]
-                })
-        })
-    }
-}
diff --git a/ayafs/src/memory/dir_entry.rs b/ayafs/src/memory/dir_entry.rs
deleted file mode 100644
index c013e1e..0000000
--- a/ayafs/src/memory/dir_entry.rs
+++ /dev/null
@@ -1,305 +0,0 @@
-use crate::disk::block::{DirectoryBlock, DirectoryEntry};
-use crate::disk::inode::Inode;
-use crate::AyaFS;
-use indexmap::IndexMap;
-use libc::{c_int, ENOENT, ENOSPC};
-use log::debug;
-use std::ffi::{OsStr, OsString};
-use std::os::unix::ffi::OsStrExt;
-use indexmap::map::Entry::Occupied;
-
-impl AyaFS {
-    pub(crate) fn init_direntry_map(&mut self, index: usize) {
-        let direntry_map: IndexMap<OsString, DirectoryEntry> = IndexMap::new();
-        if let Some((old_inode_index, old_dir_entry_map)) =
-            self.dir_entry_map.push(index, direntry_map)
-        {
-            if let Some(old_inode) = self.get_inode(old_inode_index) {
-                let mut old_inode = old_inode.clone();
-                self.write_back_direntry(old_inode_index, &mut old_inode, old_dir_entry_map)
-                    .unwrap();
-                self.update_inode(old_inode_index, old_inode);
-            }
-        }
-    }
-
-    pub(crate) fn load_direntry_map(&mut self, index: usize, inode: &Inode) -> Result<(), c_int> {
-        if self.dir_entry_map.contains(&index) {
-            debug!("load_direntry_map(ino: {}) already in cache", index);
-            return Ok(());
-        }
-
-        debug!("load_direntry_map(ino: {}) loading", index);
-        let mut dir_entry_map: IndexMap<OsString, DirectoryEntry> = IndexMap::new();
-        let mut entry_index: usize = 0;
-        loop {
-            let block_index_within_inode = entry_index / 15;
-            let entry_index_within_block = entry_index % 15;
-
-            match self.access_block::<DirectoryBlock>(inode, block_index_within_inode) {
-                Some(directory_block) => {
-                    if directory_block.block.query(entry_index_within_block) {
-                        let dir_entry = &directory_block.block.entries[entry_index_within_block];
-                        let name = dir_entry.name();
-                        dir_entry_map.insert(name, dir_entry.clone());
-                    } else {
-                        break;
-                    }
-                }
-                None => break,
-            }
-            entry_index += 1;
-        }
-
-        if let Some((old_inode_index, old_dir_entry_map)) =
-            self.dir_entry_map.push(index, dir_entry_map)
-        {
-            if let Some(old_inode) = self.get_inode(old_inode_index) {
-                let mut old_inode = old_inode.clone();
-                self.write_back_direntry(old_inode_index, &mut old_inode, old_dir_entry_map)?;
-                self.update_inode(old_inode_index, old_inode);
-            }
-        }
-
-        Ok(())
-    }
-
-    pub(crate) fn write_back_direntry(
-        &mut self,
-        _parent_index: usize,
-        parent_inode: &mut Inode,
-        dir_entry_map: IndexMap<OsString, DirectoryEntry>,
-    ) -> Result<(), c_int> {
-        for (entry_index, (_, dir_entry)) in dir_entry_map.into_iter().enumerate() {
-            let block_index_within_inode = entry_index / 15;
-            let entry_index_within_block = entry_index % 15;
-            // 不够就新分配
-            if self
-                .get_block_index(parent_inode, block_index_within_inode)
-                .is_none()
-            {
-                match self.allocate_block_for(parent_inode) {
-                    Some((_, block_index_within)) => {
-                        assert_eq!(block_index_within, block_index_within_inode);
-                    }
-                    None => {
-                        return Err(ENOSPC);
-                    }
-                }
-            }
-            match self.access_block_mut::<DirectoryBlock>(parent_inode, block_index_within_inode) {
-                Some(directory_block) => {
-                    directory_block.block.allocate(entry_index_within_block);
-                    directory_block.block.entries[entry_index_within_block] = dir_entry;
-                }
-                None => {
-                    return Err(ENOENT);
-                }
-            }
-        }
-        Ok(())
-    }
-
-    pub(crate) fn exchange_direntry<T: AsRef<OsStr>>(
-        &mut self,
-        parent_index: usize,
-        parent_inode: &mut Inode,
-        name: T,
-        new_parent_index: usize,
-        new_parent_inode: &mut Inode,
-        new_name: T,
-    ) -> Result<(), c_int> {
-        self.load_direntry_map(parent_index, parent_inode)?;
-        self.load_direntry_map(new_parent_index, new_parent_inode)?;
-
-        let dir_entry = self.dir_entry_map
-            .get(&parent_index)
-            .ok_or(ENOENT)?
-            .get(name.as_ref())
-            .cloned()
-            .ok_or(ENOENT)?;
-        let new_dir_entry = self.dir_entry_map
-            .get(&new_parent_index)
-            .ok_or(ENOENT)?
-            .get(new_name.as_ref())
-            .cloned()
-            .ok_or(ENOENT)?;
-
-        let name: &OsStr = name.as_ref();
-        let new_name: &OsStr = new_name.as_ref();
-
-        self.dir_entry_map
-            .get_mut(&parent_index)
-            .map(|dir_entry_map| {
-                if let Occupied(mut entry) = dir_entry_map.entry(name.to_os_string()) {
-                    *entry.get_mut() = new_dir_entry.clone();
-                }
-            })
-            .ok_or(ENOENT)?;
-        self.dir_entry_map
-            .get_mut(&new_parent_index)
-            .map(|new_dir_entry_map| {
-                if let Occupied(mut entry) = new_dir_entry_map.entry(new_name.to_os_string()) {
-                    *entry.get_mut() = dir_entry.clone();
-                }
-            })
-            .ok_or(ENOENT)?;
-
-        Ok(())
-    }
-
-    /// 删除第 entry_index 个 dir entry
-    pub(crate) fn remove_direntry<T: AsRef<OsStr>>(
-        &mut self,
-        parent_index: usize,
-        parent_inode: &mut Inode,
-        name: T,
-        _entry_index: u32,
-    ) -> Result<(), c_int> {
-        self.load_direntry_map(parent_index, parent_inode)?;
-        if let Some(dir_entry_map) = self.dir_entry_map.get_mut(&parent_index) {
-            debug!("  remove_direntry(ino: {}) using hashmap", parent_index);
-            if dir_entry_map.shift_remove(name.as_ref()).is_some() {
-                Ok(())
-            } else {
-                Err(ENOENT)
-            }
-        } else {
-            Err(ENOENT)
-        }
-    }
-
-    pub(crate) fn add_direntry_2<T: AsRef<OsStr>>(
-        &mut self,
-        parent_index: usize,
-        parent_inode: &mut Inode,
-        child_inode_name: T,
-        dir_entry: DirectoryEntry,
-    ) -> Result<u32, c_int> {
-        let child_inode_name = child_inode_name.as_ref();
-        self.load_direntry_map(parent_index, parent_inode)?;
-        if let Some(dir_entry_map) = self.dir_entry_map.get_mut(&parent_index) {
-            let (entry_index, _) =
-                dir_entry_map.insert_full(child_inode_name.to_os_string(), dir_entry);
-            debug!(
-                "  add_direntry(ino: {}) using hashmap, entry {}",
-                parent_index, entry_index
-            );
-            parent_inode.size += 1;
-            Ok(entry_index as u32)
-        } else {
-            Err(ENOENT)
-        }
-    }
-
-    pub(crate) fn add_direntry<T: AsRef<OsStr>>(
-        &mut self,
-        parent_index: usize,
-        parent_inode: &mut Inode,
-        child_inode_index: usize,
-        child_inode_name: T,
-        file_type: u8,
-    ) -> Result<u32, c_int> {
-        let child_inode_name = child_inode_name.as_ref();
-        self.load_direntry_map(parent_index, parent_inode)?;
-        if let Some(dir_entry_map) = self.dir_entry_map.get_mut(&parent_index) {
-            let name_len = child_inode_name.len() as u8;
-            let mut name = [0u8; 256];
-            (&mut name[0..child_inode_name.len()]).copy_from_slice(child_inode_name.as_bytes());
-
-            let dir_entry = DirectoryEntry {
-                inode: child_inode_index as u32,
-                record_len: 264,
-                name_len,
-                file_type,
-                name,
-            };
-
-            let (entry_index, _) =
-                dir_entry_map.insert_full(child_inode_name.to_os_string(), dir_entry);
-            debug!(
-                "  add_direntry(ino: {}) using hashmap, entry {}",
-                parent_index, entry_index
-            );
-            parent_inode.size += 1;
-            Ok(entry_index as u32)
-        } else {
-            Err(ENOENT)
-        }
-    }
-
-    pub(crate) fn get_direntry_by_name<T: AsRef<OsStr>>(
-        &mut self,
-        parent_index: usize,
-        parent_inode: &Inode,
-        name: T,
-    ) -> Result<DirectoryEntry, c_int> {
-        self.load_direntry_map(parent_index, parent_inode)?;
-        if let Some(dir_entry_map) = self.dir_entry_map.get(&parent_index) {
-            debug!(
-                "  get_direntry(ino: {}, name: {:?}) using hashmap",
-                parent_index, name.as_ref()
-            );
-            dir_entry_map
-                .get(name.as_ref())
-                .cloned()
-                .ok_or(ENOENT)
-        } else {
-            Err(ENOENT)
-        }
-    }
-
-    pub(crate) fn get_direntry(
-        &mut self,
-        parent_index: usize,
-        parent_inode: &Inode,
-        entry_index: u32,
-    ) -> Result<DirectoryEntry, c_int> {
-        self.load_direntry_map(parent_index, parent_inode)?;
-        if let Some(dir_entry_map) = self.dir_entry_map.get(&parent_index) {
-            debug!(
-                "  get_direntry(ino: {}, entry_index: {}) using hashmap",
-                parent_index, entry_index
-            );
-            dir_entry_map
-                .iter()
-                .skip(entry_index as usize)
-                .next()
-                .map(|entry| entry.1.clone())
-                .ok_or(ENOENT)
-        } else {
-            Err(ENOENT)
-        }
-    }
-
-    /// 返回 inode_index, inode 在 parent 里的 index, inode 本身
-    pub fn lookup_name(
-        &mut self,
-        parent_index: usize,
-        parent_inode: &Inode,
-        name: &OsStr,
-    ) -> Result<(u32, u32, Inode), c_int> {
-        self.load_direntry_map(parent_index, parent_inode)?;
-        if let Some(dir_entry_map) = self.dir_entry_map.get(&parent_index) {
-            if let Some((entry_index, _, dir_entry)) = dir_entry_map.get_full(name) {
-                let inode_index = dir_entry.inode;
-                let inode = self.get_inode(inode_index as usize).unwrap().clone();
-                Ok((inode_index, entry_index as u32, inode))
-            } else {
-                Err(ENOENT)
-            }
-        } else {
-            let mut entry_index = 0;
-            while entry_index < parent_inode.size {
-                if let Ok(entry) = self.get_direntry(parent_index, parent_inode, entry_index) {
-                    if entry.name() == name {
-                        let inode = self.get_inode(entry.inode as usize).unwrap().clone();
-                        return Ok((entry.inode, entry_index, inode));
-                    }
-                }
-                entry_index += 1;
-            }
-            Err(ENOENT)
-        }
-    }
-}
diff --git a/ayafs/src/memory/file_handle.rs b/ayafs/src/memory/file_handle.rs
deleted file mode 100644
index c821619..0000000
--- a/ayafs/src/memory/file_handle.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-use crate::AyaFS;
-use std::sync::atomic::Ordering;
-
-impl AyaFS {
-    pub(crate) fn allocate_file_descriptor(
-        &mut self,
-        inode_index: usize,
-        read: bool,
-        write: bool,
-    ) -> u64 {
-        let fd = self.next_file_handle.fetch_add(1, Ordering::SeqCst);
-        self.file_handle_map.insert(fd, (inode_index, read, write));
-        fd
-    }
-}
diff --git a/ayafs/src/memory/mod.rs b/ayafs/src/memory/mod.rs
deleted file mode 100644
index d1f1ab8..0000000
--- a/ayafs/src/memory/mod.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-/// In-memory data structures and logic.
-/// This is where the crucial block and inode methods presented to upper calls implemented.
-pub mod cached_block;
-pub mod cached_inode;
-mod dir_entry;
-mod file_handle;
diff --git a/ayafs/src/tests/bitmap.rs b/ayafs/src/tests/bitmap.rs
deleted file mode 100644
index 1a43f09..0000000
--- a/ayafs/src/tests/bitmap.rs
+++ /dev/null
@@ -1,38 +0,0 @@
-use crate::tests::common;
-use indexmap::IndexMap;
-
-#[test]
-fn test_allocate() {
-    let mut fs = common::setup();
-    for _ in 0..10 {
-        fs.data_bitmap.allocate().unwrap();
-    }
-    assert!(fs.data_bitmap.deallocate(5));
-    assert_eq!(fs.data_bitmap.allocate().unwrap(), 5);
-    assert_eq!(fs.data_bitmap.allocate().unwrap(), 11);
-}
-
-#[test]
-fn test_query() {
-    let mut fs = common::setup();
-    for _ in 0..10 {
-        fs.data_bitmap.allocate().unwrap();
-    }
-    assert_eq!(fs.data_bitmap.query(0), false);
-    assert_eq!(fs.data_bitmap.query(5), true);
-    assert_eq!(fs.data_bitmap.query(11), false);
-}
-
-#[test]
-fn test_index_map() {
-    let mut map: IndexMap<i32, i32> = IndexMap::new();
-    map.insert(1, 2);
-    map.insert(2, 3);
-    map.insert(3, 4);
-    map.insert(4, 5);
-    map.remove(&3);
-
-    for (entry_index, (key, value)) in map.iter().enumerate() {
-        println!("index {}, key {}, value {}", entry_index, key, value);
-    }
-}
diff --git a/ayafs/src/tests/block_cache.rs b/ayafs/src/tests/block_cache.rs
deleted file mode 100644
index 52117b9..0000000
--- a/ayafs/src/tests/block_cache.rs
+++ /dev/null
@@ -1,245 +0,0 @@
-use crate::disk::block::{DataBlock, DoubleIndirectBlock, IndirectBlock};
-use crate::disk::inode::InodeMode;
-use crate::tests::common;
-
-#[test]
-fn test_basic_lru() {
-    let mut fs = common::setup();
-
-    let v: Vec<usize> = (1..=256)
-        .map(|_| {
-            let index = fs.data_bitmap.allocate().unwrap();
-            fs.get_block::<DataBlock>(index).unwrap();
-            index
-        })
-        .collect();
-    assert!(fs.peek_block::<DataBlock>(v[0]).is_some());
-
-    for i in 0..256 {
-        let index = fs.data_bitmap.allocate().unwrap();
-        fs.get_block::<DataBlock>(index).unwrap();
-        assert!(fs.peek_block::<DataBlock>(v[i]).is_none());
-    }
-}
-
-#[test]
-fn test_inode_allocation() {
-    let mut fs = common::setup();
-
-    let (inode_index, inode) = fs.create_directory(0o755, 0, 0, 0, None).unwrap();
-    let mut inode = inode.clone();
-
-    const DIRECT_NUMBER: u32 = 15;
-    const INDIRECT_NUMBER: u32 = 1024;
-    // const DOUBLE_INDIRECT_NUMBER: u32 = 1024 * 1024;
-
-    for i in 0..DIRECT_NUMBER {
-        fs.allocate_block_for(&mut inode).unwrap();
-        assert!(fs.data_bitmap.query(inode.direct[i as usize] as usize))
-    }
-
-    for _i in 0..INDIRECT_NUMBER {
-        fs.allocate_block_for(&mut inode).unwrap();
-    }
-
-    println!("single indirect is {}", inode.single_indirect);
-    println!("double indirect is {}", inode.double_indirect);
-    println!("triple indirect is {}", inode.triple_indirect);
-
-    let indirect_block = fs
-        .peek_block::<IndirectBlock>(inode.single_indirect as usize)
-        .unwrap();
-    for entry in indirect_block.block.entries {
-        assert_ne!(entry, 0);
-        assert!(fs.data_bitmap.query(entry as usize));
-    }
-
-    assert_eq!(fs.data_bitmap.query(inode.double_indirect as usize), false);
-    assert_eq!(fs.data_bitmap.query(inode.triple_indirect as usize), false);
-
-    for _i in 0..INDIRECT_NUMBER {
-        fs.allocate_block_for(&mut inode).unwrap();
-    }
-
-    let double_indirect = inode.double_indirect;
-    println!(
-        "double indirect is {} after allocation",
-        inode.double_indirect
-    );
-
-    fs.update_inode(inode_index, inode);
-
-    assert!(fs.data_bitmap.query(double_indirect as usize));
-}
-
-#[test]
-fn test_inode_deallocation() {
-    let mut fs = common::setup();
-
-    let (inode_index, inode) = fs.create_directory(0o755, 0, 0, 0, None).unwrap();
-    let mut inode = inode.clone();
-
-    const DIRECT_NUMBER: u32 = 15;
-    const INDIRECT_NUMBER: u32 = 1024;
-    // const DOUBLE_INDIRECT_NUMBER: u32 = 1024 * 1024;
-
-    for i in 0..DIRECT_NUMBER {
-        println!("Allocated {:?}", fs.allocate_block_for(&mut inode).unwrap());
-        assert!(fs.data_bitmap.query(inode.direct[i as usize] as usize))
-    }
-
-    for _i in 0..2 * INDIRECT_NUMBER {
-        println!("Allocated {:?}", fs.allocate_block_for(&mut inode).unwrap());
-    }
-
-    println!("single indirect is {}", inode.single_indirect);
-    println!("double indirect is {}", inode.double_indirect);
-    println!("triple indirect is {}", inode.triple_indirect);
-
-    assert!(fs.data_bitmap.query(inode.double_indirect as usize));
-
-    for i in 0..INDIRECT_NUMBER + 5 {
-        println!(
-            "Deallocated {}",
-            fs.deallocate_block_for(&mut inode).unwrap()
-        );
-    }
-
-    println!("single indirect is {}", inode.single_indirect);
-    println!("double indirect is {}", inode.double_indirect);
-    println!("triple indirect is {}", inode.triple_indirect);
-
-    assert_eq!(fs.data_bitmap.query(inode.double_indirect as usize), false);
-
-    fs.update_inode(inode_index, inode);
-}
-
-#[test]
-fn test_multiple_inode_allocation() {
-    let mut fs = common::setup();
-
-    let (inode_index_1, inode_1) = fs.create_directory(0o755, 0, 0, 0, None).unwrap();
-    let mut inode_1 = inode_1.clone();
-
-    let (inode_index_2, inode_2) = fs.create_file(0o755, 0, 0, 0).unwrap();
-    let mut inode_2 = inode_2.clone();
-    // let mut inode_1 = fs.get_inode(inode_index_1).unwrap().clone();
-    // let mut inode_2 = fs.get_inode(inode_index_2).unwrap().clone();
-
-    const DIRECT_NUMBER: u32 = 15;
-    const INDIRECT_NUMBER: u32 = 1024;
-
-    for i in 0..DIRECT_NUMBER + INDIRECT_NUMBER {
-        println!(
-            "Allocated {:?} in inode {}",
-            fs.allocate_block_for(&mut inode_1).unwrap(),
-            inode_index_1
-        );
-        println!(
-            "Allocated {:?} in inode {}",
-            fs.allocate_block_for(&mut inode_2).unwrap(),
-            inode_index_2
-        );
-    }
-
-    let (inode_index_3, inode_3) = fs.create_directory(0o755, 0, 0, 0, None).unwrap();
-    let mut inode_3 = inode_3.clone();
-    // let mut inode_3 = fs.get_inode(inode_index_3).unwrap().clone();
-
-    for _i in 0..INDIRECT_NUMBER {
-        println!(
-            "Deallocated {} in inode {}",
-            fs.deallocate_block_for(&mut inode_1).unwrap(),
-            inode_index_1
-        );
-        println!(
-            "Allocated {:?} in inode {}",
-            fs.allocate_block_for(&mut inode_3).unwrap(),
-            inode_index_3
-        );
-    }
-
-    for _i in 0..DIRECT_NUMBER {
-        println!(
-            "Deallocated {} in inode {}",
-            fs.deallocate_block_for(&mut inode_1).unwrap(),
-            inode_index_1
-        );
-    }
-
-    assert!(fs.deallocate_block_for(&mut inode_1).is_none());
-
-    println!(
-        "single indirect is {} for {}",
-        inode_1.single_indirect, inode_index_1
-    );
-    println!(
-        "double indirect is {} for {}",
-        inode_1.double_indirect, inode_index_1
-    );
-    println!(
-        "single indirect is {} for {}",
-        inode_2.single_indirect, inode_index_2
-    );
-    println!(
-        "double indirect is {} for {}",
-        inode_2.double_indirect, inode_index_2
-    );
-    println!(
-        "single indirect is {} for {}",
-        inode_3.single_indirect, inode_index_3
-    );
-    println!(
-        "double indirect is {} for {}",
-        inode_3.double_indirect, inode_index_3
-    );
-
-    assert_eq!(
-        fs.data_bitmap.query(inode_1.single_indirect as usize),
-        false
-    );
-    assert!(fs.data_bitmap.query(inode_2.single_indirect as usize));
-    assert_eq!(
-        fs.data_bitmap.query(inode_2.double_indirect as usize),
-        false
-    );
-    assert!(fs.data_bitmap.query(inode_3.single_indirect as usize));
-    assert_eq!(
-        fs.data_bitmap.query(inode_3.double_indirect as usize),
-        false
-    );
-
-    fs.allocate_block_for(&mut inode_2).unwrap();
-    println!("-----------------");
-    println!(
-        "double indirect is {} for {}",
-        inode_2.double_indirect, inode_index_2
-    );
-
-    assert!(fs.data_bitmap.query(inode_2.double_indirect as usize));
-
-    for _i in 0..DIRECT_NUMBER {
-        fs.allocate_block_for(&mut inode_3).unwrap();
-    }
-    println!("-----------------");
-    println!(
-        "double indirect is {} for {}",
-        inode_3.double_indirect, inode_index_3
-    );
-    assert_eq!(
-        fs.data_bitmap.query(inode_3.double_indirect as usize),
-        false
-    );
-
-    fs.allocate_block_for(&mut inode_3).unwrap();
-    println!("-----------------");
-    println!(
-        "double indirect is {} for {}",
-        inode_3.double_indirect, inode_index_3
-    );
-    assert!(fs.data_bitmap.query(inode_3.double_indirect as usize));
-
-    fs.update_inode(inode_index_1, inode_1);
-    fs.update_inode(inode_index_2, inode_2);
-    fs.update_inode(inode_index_3, inode_3);
-}
diff --git a/ayafs/src/tests/common/mod.rs b/ayafs/src/tests/common/mod.rs
deleted file mode 100644
index 3abfcb4..0000000
--- a/ayafs/src/tests/common/mod.rs
+++ /dev/null
@@ -1,9 +0,0 @@
-use crate::block_device::memory_disk::MemoryDisk;
-use crate::AyaFS;
-use std::sync::Arc;
-
-#[allow(unused)]
-pub(crate) fn setup() -> AyaFS {
-    let mem_disk = Arc::new(MemoryDisk::new(1059715));
-    AyaFS::new(mem_disk, 1059715)
-}
diff --git a/ayafs/src/tests/mod.rs b/ayafs/src/tests/mod.rs
deleted file mode 100644
index df442c1..0000000
--- a/ayafs/src/tests/mod.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-#[cfg(test)]
-mod bitmap;
-mod common;
-
-#[cfg(test)]
-mod block_cache;
diff --git a/ayafs/src/utils/constants.rs b/ayafs/src/utils/constants.rs
deleted file mode 100644
index 8b13789..0000000
--- a/ayafs/src/utils/constants.rs
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/ayafs/src/utils/mod.rs b/ayafs/src/utils/mod.rs
deleted file mode 100644
index 468ebdb..0000000
--- a/ayafs/src/utils/mod.rs
+++ /dev/null
@@ -1,92 +0,0 @@
-mod constants;
-pub mod permissions;
-
-use crate::block_device::BLOCK_SIZE;
-use crate::disk::inode::{Inode, INODE_SIZE};
-use crate::{AyaFS, INODE_PER_BLOCK};
-use fuser::{FileAttr, FileType};
-use std::time::{Duration, SystemTime, UNIX_EPOCH};
-
-pub(crate) fn time_now() -> u32 {
-    SystemTime::now()
-        .duration_since(UNIX_EPOCH)
-        .expect("How can current time be earlier than UNIX_EPOCH?")
-        .as_secs() as u32
-}
-
-pub(crate) fn from_systime(system_time: SystemTime) -> u32 {
-    system_time
-        .duration_since(UNIX_EPOCH)
-        .expect("How can current time be earlier than UNIX_EPOCH?")
-        .as_secs() as u32
-}
-
-pub(crate) fn to_systime(time: u32) -> SystemTime {
-    UNIX_EPOCH + Duration::from_secs(time as u64)
-}
-
-// File type code, one of:
-// 0x0 	Unknown.
-// 0x1 	Regular file.
-// 0x2 	Directory.
-// 0x3 	Character device file.
-// 0x4 	Block device file.
-// 0x5 	FIFO.
-// 0x6 	Socket.
-// 0x7 	Symbolic link.
-
-pub(crate) fn from_filetype(file_type: FileType) -> u8 {
-    match file_type {
-        FileType::NamedPipe => 0x5,
-        FileType::CharDevice => 0x3,
-        FileType::BlockDevice => 0x4,
-        FileType::Directory => 0x2,
-        FileType::RegularFile => 0x1,
-        FileType::Symlink => 0x7,
-        FileType::Socket => 0x6,
-    }
-}
-
-pub(crate) fn to_filetype(file_type: u8) -> Option<FileType> {
-    match file_type {
-        0x0 => None,
-        0x1 => Some(FileType::RegularFile),
-        0x2 => Some(FileType::Directory),
-        0x3 => Some(FileType::CharDevice),
-        0x4 => Some(FileType::BlockDevice),
-        0x5 => Some(FileType::NamedPipe),
-        0x6 => Some(FileType::Socket),
-        0x7 => Some(FileType::Symlink),
-        _ => panic!("bad filetype"),
-    }
-}
-
-pub(crate) fn to_fileattr(inode_index: usize, inode: &Inode) -> FileAttr {
-    FileAttr {
-        ino: inode_index as u64,
-        size: inode.size as u64,
-        blocks: inode.n_blocks as u64,
-        atime: to_systime(inode.atime),
-        mtime: to_systime(inode.mtime),
-        ctime: to_systime(inode.ctime),
-        crtime: to_systime(inode.crtime),
-        kind: inode.mode.into(),
-        perm: inode.mode.perm(),
-        nlink: inode.n_links as u32,
-        uid: inode.uid,
-        gid: inode.gid,
-        rdev: 0,
-        blksize: BLOCK_SIZE as u32,
-        flags: inode.flags,
-    }
-}
-
-impl AyaFS {
-    /// 输入 inode 编号, 返回它对应的 block number 和 block 内 offset
-    pub(crate) fn locate_inode(&self, inode_index: usize) -> (usize, usize) {
-        let block_number =
-            inode_index / INODE_PER_BLOCK + 1 + self.inode_bitmap.length + self.data_bitmap.length;
-        let block_offset = inode_index % INODE_PER_BLOCK * INODE_SIZE;
-        (block_number, block_offset)
-    }
-}
diff --git a/ayafs/src/utils/permissions.rs b/ayafs/src/utils/permissions.rs
deleted file mode 100644
index 6773511..0000000
--- a/ayafs/src/utils/permissions.rs
+++ /dev/null
@@ -1,62 +0,0 @@
-use crate::disk::inode::InodeMode;
-use libc::{F_OK, S_ISGID, S_ISUID, S_IXGRP, X_OK};
-use std::fs::File;
-use std::io::BufRead;
-
-pub(crate) fn get_groups(pid: u32) -> Vec<u32> {
-    let file = File::open(format!("/proc/{pid}/task/{pid}/status"))
-        .expect(format!("pid {pid} incorrect!").as_str());
-    for line in std::io::BufReader::new(file).lines() {
-        let line = line.unwrap();
-        if line.starts_with("Groups:") {
-            return line["Groups: ".len()..]
-                .split(' ')
-                .filter(|x| !x.trim().is_empty())
-                .map(|x| x.parse::<u32>().unwrap())
-                .collect();
-        }
-    }
-
-    Vec::new()
-}
-
-pub(crate) fn clear_suid_sgid(mut mode: InodeMode) -> InodeMode {
-    mode.0 &= !S_ISUID as u16;
-    if mode.0 & S_IXGRP as u16 != 0 {
-        mode.0 &= !S_ISGID as u16;
-    }
-    mode
-}
-
-pub(crate) fn check_access(
-    incoming_uid: u32,
-    incoming_gid: u32,
-    uid: u32,
-    gid: u32,
-    mode: InodeMode,
-    mut mask: i32,
-) -> bool {
-    if mask == F_OK {
-        return true;
-    }
-
-    let perm = i32::from(mode.0);
-    // root
-    if incoming_uid == 0 {
-        // 读写任何东西都是可以的, 执行只有 IXOTH/IXGRP/IXUSR 之一设置才可以
-        mask &= X_OK;
-        mask -= mask & (perm >> 6);
-        mask -= mask & (perm >> 3);
-        mask -= mask & perm;
-        return mask == 0;
-    }
-
-    if incoming_uid == uid {
-        mask -= mask & (perm >> 6);
-    } else if incoming_gid == gid {
-        mask -= mask & (perm >> 3);
-    } else {
-        mask -= mask & perm;
-    }
-    mask == 0
-}