diff --git a/kernel/rustkernel/src/arch/mod.rs b/kernel/rustkernel/src/arch/mod.rs
index 7fc8fb9..cd9646b 100644
--- a/kernel/rustkernel/src/arch/mod.rs
+++ b/kernel/rustkernel/src/arch/mod.rs
@@ -45,7 +45,10 @@ pub mod mem {
 
 pub mod virtual_memory {
     #[cfg(target_arch = "riscv64")]
-    pub use super::riscv::virtual_memory::{kvminit as init, kvminithart as inithart, copyin, copyinstr, copyout, mappages, uvmalloc, uvmcopy, uvmcreate, uvmdealloc, uvmfree, uvmunmap};
+    pub use super::riscv::virtual_memory::{
+        copyin, copyinstr, copyout, kvminit as init, kvminithart as inithart, mappages, uvmalloc,
+        uvmcopy, uvmcreate, uvmdealloc, uvmfree, uvmunmap,
+    };
 }
 
 pub mod power {
diff --git a/kernel/rustkernel/src/arch/riscv/trap.rs b/kernel/rustkernel/src/arch/riscv/trap.rs
index 9395dd7..eefa7a9 100644
--- a/kernel/rustkernel/src/arch/riscv/trap.rs
+++ b/kernel/rustkernel/src/arch/riscv/trap.rs
@@ -57,7 +57,7 @@ pub unsafe fn devintr() -> i32 {
         let irq = interrupt::handle_interrupt();
 
         if irq == UART0_IRQ {
-            crate::console::uart::UART0.interrupt();
+            crate::hardware::uart::UART0.interrupt();
         } else if irq == VIRTIO0_IRQ {
             virtio_disk_intr();
         } else if irq > 0 {
diff --git a/kernel/rustkernel/src/arch/riscv/virtual_memory.rs b/kernel/rustkernel/src/arch/riscv/virtual_memory.rs
index bfabde4..9fc9aa9 100644
--- a/kernel/rustkernel/src/arch/riscv/virtual_memory.rs
+++ b/kernel/rustkernel/src/arch/riscv/virtual_memory.rs
@@ -1,4 +1,9 @@
-use super::{asm, mem::{make_satp, pte2pa}, plic::PLIC, power::QEMU_POWER};
+use super::{
+    asm,
+    mem::{make_satp, pte2pa},
+    plic::PLIC,
+    power::QEMU_POWER,
+};
 use crate::{
     arch::{
         self,
diff --git a/kernel/rustkernel/src/console/mod.rs b/kernel/rustkernel/src/console/mod.rs
index 6efb13b..5accd3c 100644
--- a/kernel/rustkernel/src/console/mod.rs
+++ b/kernel/rustkernel/src/console/mod.rs
@@ -9,10 +9,10 @@
 // - ctrl-p: print process list
 
 pub mod printf;
-pub mod uart;
 
 use crate::{
     fs::file::{devsw, CONSOLE},
+    hardware::uart::UART0,
     proc::{
         process::{procdump, Process},
         scheduler::wakeup,
@@ -20,7 +20,6 @@ use crate::{
     sync::mutex::Mutex,
 };
 use core::{ffi::c_void, ptr::addr_of_mut};
-use uart::UART0;
 
 extern "C" {
     fn either_copyin(dst: *mut c_void, user_src: i32, src: u64, len: u64) -> i32;
diff --git a/kernel/rustkernel/src/console/printf.rs b/kernel/rustkernel/src/console/printf.rs
index abf358e..071a70e 100644
--- a/kernel/rustkernel/src/console/printf.rs
+++ b/kernel/rustkernel/src/console/printf.rs
@@ -30,13 +30,13 @@ pub(crate) use println;
 /// Does not use any locks.
 macro_rules! uprint {
     ($($arg:tt)*) => {{
-        use $crate::console::uart::Uart;
+        use $crate::hardware::uart::Uart;
         use core::fmt::Write;
 
         // Do some casts to get a mutable reference.
         // Safe because Uart's core::fmt::Write implementation
         // only uses the &mut reference immutably.
-        let uart: *const Uart = &$crate::console::uart::UART0 as *const Uart;
+        let uart: *const Uart = &$crate::hardware::uart::UART0 as *const Uart;
         let uart: &mut Uart = unsafe { &mut *uart.cast_mut() };
 
         let _ = core::write!(uart, $($arg)*);
diff --git a/kernel/rustkernel/src/fs/file.rs b/kernel/rustkernel/src/fs/file.rs
index 1243921..6b89c61 100644
--- a/kernel/rustkernel/src/fs/file.rs
+++ b/kernel/rustkernel/src/fs/file.rs
@@ -1,9 +1,9 @@
 //! Support functions for system calls that involve file descriptors.
 
 use crate::{
+    arch::virtual_memory::copyout,
     fs::{log, stat::Stat},
     io::pipe::Pipe,
-    arch::virtual_memory::copyout,
     proc::process::Process,
     sync::{sleeplock::Sleeplock, spinlock::Spinlock},
 };
diff --git a/kernel/rustkernel/src/fs/mod.rs b/kernel/rustkernel/src/fs/mod.rs
index dde2296..458997b 100644
--- a/kernel/rustkernel/src/fs/mod.rs
+++ b/kernel/rustkernel/src/fs/mod.rs
@@ -3,9 +3,7 @@
 
 pub mod file;
 pub mod log;
-pub mod ramdisk;
 pub mod stat;
-pub mod virtio_disk;
 
 use crate::fs::file::Inode;
 
diff --git a/kernel/rustkernel/src/hardware/mod.rs b/kernel/rustkernel/src/hardware/mod.rs
new file mode 100644
index 0000000..d4db234
--- /dev/null
+++ b/kernel/rustkernel/src/hardware/mod.rs
@@ -0,0 +1,5 @@
+//! Device drivers and hardware implementations.
+
+pub mod ramdisk;
+pub mod uart;
+pub mod virtio_disk;
diff --git a/kernel/rustkernel/src/fs/ramdisk.rs b/kernel/rustkernel/src/hardware/ramdisk.rs
similarity index 100%
rename from kernel/rustkernel/src/fs/ramdisk.rs
rename to kernel/rustkernel/src/hardware/ramdisk.rs
diff --git a/kernel/rustkernel/src/console/uart.rs b/kernel/rustkernel/src/hardware/uart.rs
similarity index 100%
rename from kernel/rustkernel/src/console/uart.rs
rename to kernel/rustkernel/src/hardware/uart.rs
diff --git a/kernel/rustkernel/src/fs/virtio_disk.rs b/kernel/rustkernel/src/hardware/virtio_disk.rs
similarity index 100%
rename from kernel/rustkernel/src/fs/virtio_disk.rs
rename to kernel/rustkernel/src/hardware/virtio_disk.rs
diff --git a/kernel/rustkernel/src/io/pipe.rs b/kernel/rustkernel/src/io/pipe.rs
index 731040e..a156158 100644
--- a/kernel/rustkernel/src/io/pipe.rs
+++ b/kernel/rustkernel/src/io/pipe.rs
@@ -1,7 +1,7 @@
 use crate::{
+    arch::virtual_memory::{copyin, copyout},
     fs::file::{filealloc, fileclose, File, FileType},
     mem::kalloc::{kalloc, kfree},
-    arch::virtual_memory::{copyin, copyout},
     proc::{process::Process, scheduler::wakeup},
     sync::spinlock::Spinlock,
 };
diff --git a/kernel/rustkernel/src/lib.rs b/kernel/rustkernel/src/lib.rs
index cc0f9fa..f9b1260 100644
--- a/kernel/rustkernel/src/lib.rs
+++ b/kernel/rustkernel/src/lib.rs
@@ -11,6 +11,7 @@ extern crate core;
 mod arch;
 mod console;
 mod fs;
+mod hardware;
 mod io;
 mod mem;
 mod proc;
@@ -68,7 +69,7 @@ pub unsafe fn main() -> ! {
         io::bio::binit();
         fs::iinit();
         fs::file::fileinit();
-        fs::virtio_disk::virtio_disk_init();
+        hardware::virtio_disk::virtio_disk_init();
         proc::process::userinit();
         STARTED = true;
     } else {
diff --git a/kernel/rustkernel/src/syscall.rs b/kernel/rustkernel/src/syscall.rs
index 0f088a2..b6b2b47 100644
--- a/kernel/rustkernel/src/syscall.rs
+++ b/kernel/rustkernel/src/syscall.rs
@@ -1,5 +1,9 @@
 use crate::{
-    arch::{clock::CLOCK_TICKS, power::shutdown, virtual_memory::{copyin, copyinstr}},
+    arch::{
+        clock::CLOCK_TICKS,
+        power::shutdown,
+        virtual_memory::{copyin, copyinstr},
+    },
     fs::{
         self,
         file::{self, File},