Move `Device` from sfs to vfs

Cargo.toml

@@ -12,6 +12,8 @@ panic = 'abort' # prevent `_Unwind_Resume` link error
 [dependencies]
 spin = "0.4"
 bit-set = { default-features = false, version = "0.5" } # default-features contains 'std'
+
+[target.ucore.dependencies]
 bitflags = "1.0"
 
 [features]

src/c_interface.rs

@@ -265,7 +265,7 @@ impl IoBuf {
 }
 
 // FIXME: Must block aligned
-impl sfs::Device for Device {
+impl vfs::Device for Device {
     fn read_at(&mut self, offset: usize, buf: &mut [u8]) -> Option<usize> {
         let mut io_buf = IoBuf {
             base: buf.as_mut_ptr(),

src/sfs.rs

@@ -4,18 +4,11 @@ use alloc::{boxed::Box, Vec, BTreeMap, rc::{Rc, Weak}, String};
 use core::cell::{RefCell, RefMut};
 use dirty::Dirty;
 use super::structs::*;
-use super::vfs;
+use super::vfs::{self, Device};
 use core::mem::{uninitialized, size_of};
 use core::slice;
 use core::fmt::{Debug, Formatter, Error};
 
-/// Interface for SFS to read & write
-///     TODO: use std::io::{Read, Write}
-pub trait Device {
-    fn read_at(&mut self, offset: usize, buf: &mut [u8]) -> Option<usize>;
-    fn write_at(&mut self, offset: usize, buf: &[u8]) -> Option<usize>;
-}
-
 trait DeviceExt: Device {
     fn read_block(&mut self, id: BlockId, offset: usize, buf: &mut [u8]) -> vfs::Result<()> {
         debug_assert!(offset + buf.len() <= BLKSIZE);

src/vfs.rs

@@ -4,6 +4,13 @@ use core::mem::size_of;
 use core;
 use core::fmt::Debug;
 
+/// Interface for FS to read & write
+///     TODO: use std::io::{Read, Write}
+pub trait Device {
+    fn read_at(&mut self, offset: usize, buf: &mut [u8]) -> Option<usize>;
+    fn write_at(&mut self, offset: usize, buf: &[u8]) -> Option<usize>;
+}
+
 /// Abstract operations on a inode.
 pub trait INode: Debug {
     fn open(&mut self, flags: u32) -> Result<()>;