diff --git a/kernel/rustkernel/src/arch/interrupt.rs b/kernel/rustkernel/src/arch/interrupt.rs
new file mode 100644
index 0000000..b7869ca
--- /dev/null
+++ b/kernel/rustkernel/src/arch/interrupt.rs
@@ -0,0 +1,10 @@
+//! Architecture-agnostic interrupt handling.
+
+#[cfg(target_arch = "riscv64")]
+pub use super::riscv::plic::plic_claim as handle_interrupt;
+#[cfg(target_arch = "riscv64")]
+pub use super::riscv::plic::plic_complete as complete_interrupt;
+#[cfg(target_arch = "riscv64")]
+pub use super::riscv::plic::plicinit as init;
+#[cfg(target_arch = "riscv64")]
+pub use super::riscv::plic::plicinithart as inithart;
diff --git a/kernel/rustkernel/src/arch/mod.rs b/kernel/rustkernel/src/arch/mod.rs
index fb27202..632c9a7 100644
--- a/kernel/rustkernel/src/arch/mod.rs
+++ b/kernel/rustkernel/src/arch/mod.rs
@@ -1 +1,4 @@
+#[cfg(target_arch = "riscv64")]
 pub mod riscv;
+
+pub mod interrupt;
diff --git a/kernel/rustkernel/src/arch/riscv/memlayout.rs b/kernel/rustkernel/src/arch/riscv/memlayout.rs
index 058e526..e5bfd0a 100644
--- a/kernel/rustkernel/src/arch/riscv/memlayout.rs
+++ b/kernel/rustkernel/src/arch/riscv/memlayout.rs
@@ -23,11 +23,11 @@ pub const QEMU_POWER: u64 = 0x100000u64;
 
 // QEMU puts UART registers here in physical memory.
 pub const UART0: usize = 0x10000000;
-pub const UART0_IRQ: i32 = 10;
+pub const UART0_IRQ: usize = 10;
 
 // Virtio MMIO interface
-pub const VIRTIO0: u64 = 0x10001000;
-pub const VIRTIO0_IRQ: i32 = 1;
+pub const VIRTIO0: usize = 0x10001000;
+pub const VIRTIO0_IRQ: usize = 1;
 
 // Core Local Interrupter (CLINT), which contains the timer.
 pub const CLINT: u64 = 0x2000000;
@@ -36,29 +36,6 @@ pub fn clint_mtimecmp(hartid: u64) -> u64 {
     CLINT + 0x4000 + (8 * hartid)
 }
 
-// QEMU puts platform-level interrupt controller (PLIC) here.
-pub const PLIC: u64 = 0x0c000000;
-pub const PLIC_PRIORITY: u64 = PLIC;
-pub const PLIC_PENDING: u64 = PLIC + 0x1000;
-pub fn plic_menable(hartid: u64) -> u64 {
-    PLIC + 0x2000 + (0x100 * hartid)
-}
-pub fn plic_senable(hartid: u64) -> u64 {
-    PLIC + 0x2080 + (0x100 * hartid)
-}
-pub fn plic_mpriority(hartid: u64) -> u64 {
-    PLIC + 0x200000 + (0x2000 * hartid)
-}
-pub fn plic_spriority(hartid: u64) -> u64 {
-    PLIC + 0x201000 + (0x2000 * hartid)
-}
-pub fn plic_mclaim(hartid: u64) -> u64 {
-    PLIC + 0x200004 + (0x2000 * hartid)
-}
-pub fn plic_sclaim(hartid: u64) -> u64 {
-    PLIC + 0x201004 + (0x2000 * hartid)
-}
-
 // The kernel expects there to be RAM
 // for use by the kernel and user pages
 // from physical address 0x80000000 to PHYSTOP.
diff --git a/kernel/rustkernel/src/arch/riscv/plic.rs b/kernel/rustkernel/src/arch/riscv/plic.rs
index 3729c72..1414f5f 100644
--- a/kernel/rustkernel/src/arch/riscv/plic.rs
+++ b/kernel/rustkernel/src/arch/riscv/plic.rs
@@ -1,35 +1,67 @@
 //! The RISC-V Platform Level Interrupt Controller (PLIC)
 
 use crate::{
-    arch::riscv::{plic_sclaim, plic_senable, plic_spriority, PLIC, UART0_IRQ, VIRTIO0_IRQ},
+    arch::riscv::{UART0_IRQ, VIRTIO0_IRQ},
     proc::cpu::Cpu,
 };
 
+// QEMU puts platform-level interrupt controller (PLIC) here.
+pub const PLIC: usize = 0x0c000000;
+const PLIC_PRIORITY: usize = PLIC;
+const PLIC_PENDING: usize = PLIC + 0x1000;
+const UART0_IRQ_ADDR: usize = PLIC + UART0_IRQ * 4;
+const VIRTIO0_IRQ_ADDR: usize = PLIC + VIRTIO0_IRQ * 4;
+
+/// Get a pointer to the CPU-specific machine-mode enable register.
+fn plic_menable(hartid: usize) -> *mut u32 {
+    (PLIC + 0x2000 + (0x100 * hartid)) as *mut u32
+}
+/// Get a pointer to the CPU-specific supervisor-mode enable register.
+fn plic_senable(hartid: usize) -> *mut u32 {
+    (PLIC + 0x2080 + (0x100 * hartid)) as *mut u32
+}
+/// Get a pointer to the CPU-specific machine-mode priority register.
+fn plic_mpriority(hartid: usize) -> *mut u32 {
+    (PLIC + 0x200000 + (0x2000 * hartid)) as *mut u32
+}
+/// Get a pointer to the CPU-specific supervisor-mode priority register.
+fn plic_spriority(hartid: usize) -> *mut u32 {
+    (PLIC + 0x201000 + (0x2000 * hartid)) as *mut u32
+}
+/// Get a pointer to the CPU-specific machine-mode claim register.
+fn plic_mclaim(hartid: usize) -> *mut u32 {
+    (PLIC + 0x200004 + (0x2000 * hartid)) as *mut u32
+}
+/// Get a pointer to the CPU-specific supervisor-mode claim register.
+fn plic_sclaim(hartid: usize) -> *mut u32 {
+    (PLIC + 0x201004 + (0x2000 * hartid)) as *mut u32
+}
+
 pub unsafe fn plicinit() {
     // Set desired IRQ priorities non-zero (otherwise disabled).
-    *((PLIC + UART0_IRQ as u64 * 4) as *mut u32) = 1;
-    *((PLIC + VIRTIO0_IRQ as u64 * 4) as *mut u32) = 1;
+    *(UART0_IRQ_ADDR as *mut u32) = 1;
+    *(VIRTIO0_IRQ_ADDR as *mut u32) = 1;
 }
 
 pub unsafe fn plicinithart() {
-    let hart = Cpu::current_id() as u64;
+    let hart = Cpu::current_id();
 
     // Set enable bits for this hart's S-mode
     // for the UART and VIRTIO disk.
-    *(plic_senable(hart) as *mut u32) = (1 << UART0_IRQ) | (1 << VIRTIO0_IRQ);
+    *plic_senable(hart) = (1 << UART0_IRQ) | (1 << VIRTIO0_IRQ);
 
     // Set this hart's S-mode priority threshold to 0.
-    *(plic_spriority(hart) as *mut u32) = 0;
+    *plic_spriority(hart) = 0;
 }
 
 /// Ask the PLIC what interrupt we should serve.
-pub unsafe fn plic_claim() -> i32 {
-    let hart = Cpu::current_id() as u64;
-    *(plic_sclaim(hart) as *const i32)
+pub unsafe fn plic_claim() -> usize {
+    let hart = Cpu::current_id();
+    (*plic_sclaim(hart)) as usize
 }
 
 /// Tell the PLIC we've served this IRQ.
-pub unsafe fn plic_complete(irq: i32) {
-    let hart = Cpu::current_id() as u64;
-    *(plic_sclaim(hart) as *mut i32) = irq;
+pub unsafe fn plic_complete(irq: usize) {
+    let hart = Cpu::current_id();
+    *plic_sclaim(hart) = irq as u32;
 }
diff --git a/kernel/rustkernel/src/console/printf.rs b/kernel/rustkernel/src/console/printf.rs
index eb25650..abf358e 100644
--- a/kernel/rustkernel/src/console/printf.rs
+++ b/kernel/rustkernel/src/console/printf.rs
@@ -1,8 +1,6 @@
 use crate::sync::lock::Lock;
 use core::ffi::{c_char, CStr};
 
-pub use crate::panic;
-
 pub static PRINT_LOCK: Lock = Lock::new();
 
 /// Print out formatted text to the console.
@@ -40,7 +38,7 @@ macro_rules! uprint {
         // only uses the &mut reference immutably.
         let uart: *const Uart = &$crate::console::uart::UART0 as *const Uart;
         let uart: &mut Uart = unsafe { &mut *uart.cast_mut() };
-        
+
         let _ = core::write!(uart, $($arg)*);
     }};
 }
@@ -55,7 +53,6 @@ macro_rules! uprintln {
 }
 pub(crate) use uprintln;
 
-
 #[no_mangle]
 pub extern "C" fn printint(n: i32) {
     print!("{}", n);
diff --git a/kernel/rustkernel/src/lib.rs b/kernel/rustkernel/src/lib.rs
index fca33ad..62cc173 100644
--- a/kernel/rustkernel/src/lib.rs
+++ b/kernel/rustkernel/src/lib.rs
@@ -24,7 +24,7 @@ mod trap;
 use crate::{proc::cpu::Cpu, sync::mutex::Mutex};
 use core::ffi::{c_char, CStr};
 
-pub(crate) use crate::console::printf::{print, println, uprint, uprintln};
+pub(crate) use crate::console::printf::{print, println, uprintln};
 
 pub static mut STARTED: bool = false;
 pub static PANICKED: Mutex<bool> = Mutex::new(false);
@@ -65,8 +65,8 @@ pub unsafe fn main() -> ! {
         mem::virtual_memory::kvminithart();
         proc::process::procinit();
         trap::trapinithart();
-        arch::riscv::plic::plicinit();
-        arch::riscv::plic::plicinithart();
+        arch::interrupt::init();
+        arch::interrupt::inithart();
         io::bio::binit();
         fs::iinit();
         fs::file::fileinit();
@@ -79,7 +79,7 @@ pub unsafe fn main() -> ! {
         }
         mem::virtual_memory::kvminithart();
         trap::trapinithart();
-        arch::riscv::plic::plicinithart();
+        arch::interrupt::inithart();
     }
 
     proc::scheduler::scheduler();
diff --git a/kernel/rustkernel/src/mem/virtual_memory.rs b/kernel/rustkernel/src/mem/virtual_memory.rs
index b0d976e..7cebc6a 100644
--- a/kernel/rustkernel/src/mem/virtual_memory.rs
+++ b/kernel/rustkernel/src/mem/virtual_memory.rs
@@ -1,7 +1,21 @@
 use crate::{
     arch::riscv::{
-        memlayout::{KERNBASE, PHYSTOP, TRAMPOLINE},
-        *,
+        memlayout::{KERNBASE, PHYSTOP, TRAMPOLINE, UART0, VIRTIO0, QEMU_POWER},
+        plic::PLIC,
+        asm,
+        PGSIZE,
+        pg_round_down,
+        pg_round_up,
+        Pagetable,
+        PagetableEntry,
+        PTE_V,
+        PTE_R,
+        PTE_W,
+        PTE_X,
+        PTE_U,
+        MAXVA,
+        pte2pa,
+        make_satp,
     },
     mem::{
         kalloc::{kalloc, kfree},
@@ -33,10 +47,22 @@ pub unsafe fn kvmmake() -> Pagetable {
     kvmmap(pagetable, UART0 as u64, UART0 as u64, PGSIZE, PTE_R | PTE_W);
 
     // VirtIO MMIO disk interface
-    kvmmap(pagetable, VIRTIO0, VIRTIO0, PGSIZE, PTE_R | PTE_W);
+    kvmmap(
+        pagetable,
+        VIRTIO0 as u64,
+        VIRTIO0 as u64,
+        PGSIZE,
+        PTE_R | PTE_W,
+    );
 
     // PLIC
-    kvmmap(pagetable, PLIC, PLIC, 0x400000u64, PTE_R | PTE_W);
+    kvmmap(
+        pagetable,
+        PLIC as u64,
+        PLIC as u64,
+        0x400000u64,
+        PTE_R | PTE_W,
+    );
 
     let etext_addr = addr_of!(etext) as usize as u64;
 
diff --git a/kernel/rustkernel/src/trap.rs b/kernel/rustkernel/src/trap.rs
index 8573f88..7868503 100644
--- a/kernel/rustkernel/src/trap.rs
+++ b/kernel/rustkernel/src/trap.rs
@@ -1,5 +1,5 @@
 use crate::{
-    arch::riscv::*,
+    arch::{self, riscv::*},
     println,
     proc::{
         cpu::Cpu,
@@ -49,7 +49,7 @@ pub unsafe fn devintr() -> i32 {
         // This is a supervisor external interrupt, via PLIC.
 
         // IRQ indicates which device interrupted.
-        let irq = plic::plic_claim();
+        let irq = arch::interrupt::handle_interrupt();
 
         if irq == UART0_IRQ {
             crate::console::uart::UART0.interrupt();
@@ -63,7 +63,7 @@ pub unsafe fn devintr() -> i32 {
         // interrupt at a time; tell the PLIC the device is
         // now allowed to interrupt again.
         if irq > 0 {
-            plic::plic_complete(irq);
+            arch::interrupt::complete_interrupt(irq);
         }
 
         1