diff --git a/kernel/comps/framebuffer/src/lib.rs b/kernel/comps/framebuffer/src/lib.rs
index 5bcea971..1a5f5408 100644
--- a/kernel/comps/framebuffer/src/lib.rs
+++ b/kernel/comps/framebuffer/src/lib.rs
@@ -16,7 +16,7 @@ use component::{init_component, ComponentInitError};
 use font8x8::UnicodeFonts;
 use ostd::{
     boot::{boot_info, memory_region::MemoryRegionType},
-    io_mem::IoMem,
+    io::IoMem,
     mm::{VmIo, PAGE_SIZE},
     sync::SpinLock,
 };
diff --git a/kernel/comps/virtio/src/device/input/device.rs b/kernel/comps/virtio/src/device/input/device.rs
index 71645dc6..277fb207 100644
--- a/kernel/comps/virtio/src/device/input/device.rs
+++ b/kernel/comps/virtio/src/device/input/device.rs
@@ -16,7 +16,7 @@ use aster_util::{field_ptr, safe_ptr::SafePtr};
 use bitflags::bitflags;
 use log::{debug, info};
 use ostd::{
-    io_mem::IoMem,
+    io::IoMem,
     mm::{DmaDirection, DmaStream, FrameAllocOptions, HasDaddr, VmIo, PAGE_SIZE},
     offset_of,
     sync::{LocalIrqDisabled, RwLock, SpinLock},
diff --git a/kernel/comps/virtio/src/device/input/mod.rs b/kernel/comps/virtio/src/device/input/mod.rs
index 3f5fe3a0..5dc79380 100644
--- a/kernel/comps/virtio/src/device/input/mod.rs
+++ b/kernel/comps/virtio/src/device/input/mod.rs
@@ -28,7 +28,7 @@
 
 pub mod device;
 use aster_util::safe_ptr::SafePtr;
-use ostd::{io_mem::IoMem, Pod};
+use ostd::{io::IoMem, Pod};
 
 use crate::transport::VirtioTransport;
 
diff --git a/kernel/comps/virtio/src/device/socket/config.rs b/kernel/comps/virtio/src/device/socket/config.rs
index 59b1d5c3..52f7a207 100644
--- a/kernel/comps/virtio/src/device/socket/config.rs
+++ b/kernel/comps/virtio/src/device/socket/config.rs
@@ -2,7 +2,7 @@
 
 use aster_util::safe_ptr::SafePtr;
 use bitflags::bitflags;
-use ostd::{io_mem::IoMem, mm::PodOnce, Pod};
+use ostd::{io::IoMem, mm::PodOnce, Pod};
 
 use crate::transport::VirtioTransport;
 
diff --git a/kernel/comps/virtio/src/transport/mmio/device.rs b/kernel/comps/virtio/src/transport/mmio/device.rs
index ad370ffa..c3a42ee3 100644
--- a/kernel/comps/virtio/src/transport/mmio/device.rs
+++ b/kernel/comps/virtio/src/transport/mmio/device.rs
@@ -14,7 +14,7 @@ use ostd::{
         },
         pci::cfg_space::Bar,
     },
-    io_mem::IoMem,
+    io::IoMem,
     mm::{DmaCoherent, PAGE_SIZE},
     offset_of,
     sync::RwLock,
diff --git a/kernel/comps/virtio/src/transport/mmio/multiplex.rs b/kernel/comps/virtio/src/transport/mmio/multiplex.rs
index 1d361d1f..fb97345d 100644
--- a/kernel/comps/virtio/src/transport/mmio/multiplex.rs
+++ b/kernel/comps/virtio/src/transport/mmio/multiplex.rs
@@ -6,7 +6,7 @@ use core::fmt::Debug;
 use aster_rights::{ReadOp, TRightSet, WriteOp};
 use aster_util::safe_ptr::SafePtr;
 use ostd::{
-    io_mem::IoMem,
+    io::IoMem,
     sync::RwLock,
     trap::{IrqCallbackFunction, IrqLine, TrapFrame},
 };
diff --git a/kernel/comps/virtio/src/transport/mod.rs b/kernel/comps/virtio/src/transport/mod.rs
index f75a8f3c..794457d1 100644
--- a/kernel/comps/virtio/src/transport/mod.rs
+++ b/kernel/comps/virtio/src/transport/mod.rs
@@ -7,7 +7,7 @@ use aster_util::safe_ptr::SafePtr;
 use ostd::{
     arch::device::io_port::{PortRead, PortWrite},
     bus::pci::cfg_space::Bar,
-    io_mem::IoMem,
+    io::IoMem,
     mm::{DmaCoherent, PodOnce},
     trap::IrqCallbackFunction,
     Pod,
diff --git a/kernel/comps/virtio/src/transport/pci/common_cfg.rs b/kernel/comps/virtio/src/transport/pci/common_cfg.rs
index a3b022ba..15623801 100644
--- a/kernel/comps/virtio/src/transport/pci/common_cfg.rs
+++ b/kernel/comps/virtio/src/transport/pci/common_cfg.rs
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MPL-2.0
 
 use aster_util::safe_ptr::SafePtr;
-use ostd::{io_mem::IoMem, Pod};
+use ostd::{io::IoMem, Pod};
 
 use super::capability::VirtioPciCapabilityData;
 use crate::transport::pci::capability::VirtioPciCpabilityType;
diff --git a/kernel/comps/virtio/src/transport/pci/device.rs b/kernel/comps/virtio/src/transport/pci/device.rs
index 8809c415..73d01abe 100644
--- a/kernel/comps/virtio/src/transport/pci/device.rs
+++ b/kernel/comps/virtio/src/transport/pci/device.rs
@@ -13,7 +13,7 @@ use ostd::{
         },
         BusProbeError,
     },
-    io_mem::IoMem,
+    io::IoMem,
     mm::DmaCoherent,
     offset_of,
     trap::IrqCallbackFunction,
diff --git a/kernel/comps/virtio/src/transport/pci/legacy.rs b/kernel/comps/virtio/src/transport/pci/legacy.rs
index 5cc0908e..f1902a00 100644
--- a/kernel/comps/virtio/src/transport/pci/legacy.rs
+++ b/kernel/comps/virtio/src/transport/pci/legacy.rs
@@ -10,7 +10,7 @@ use ostd::{
         pci::{capability::CapabilityData, cfg_space::Bar, common_device::PciCommonDevice},
         BusProbeError,
     },
-    io_mem::IoMem,
+    io::IoMem,
     mm::{DmaCoherent, HasDaddr, PAGE_SIZE},
     trap::IrqCallbackFunction,
 };
diff --git a/ostd/src/arch/riscv/timer/mod.rs b/ostd/src/arch/riscv/timer/mod.rs
index d6c4c75e..5c0a687f 100644
--- a/ostd/src/arch/riscv/timer/mod.rs
+++ b/ostd/src/arch/riscv/timer/mod.rs
@@ -6,7 +6,7 @@ use core::sync::atomic::{AtomicU64, Ordering};
 
 use spin::Once;
 
-use crate::{arch::boot::DEVICE_TREE, io_mem::IoMem};
+use crate::{arch::boot::DEVICE_TREE, io::IoMem};
 
 /// The timer frequency (Hz). Here we choose 1000Hz since 1000Hz is easier for unit conversion and
 /// convenient for timer. What's more, the frequency cannot be set too high or too low, 1000Hz is
diff --git a/ostd/src/bus/mmio/common_device.rs b/ostd/src/bus/mmio/common_device.rs
index 3601a669..0e67702a 100644
--- a/ostd/src/bus/mmio/common_device.rs
+++ b/ostd/src/bus/mmio/common_device.rs
@@ -7,7 +7,7 @@ use log::info;
 
 use super::VIRTIO_MMIO_MAGIC;
 use crate::{
-    io_mem::IoMem,
+    io::IoMem,
     mm::{
         paddr_to_vaddr,
         page_prop::{CachePolicy, PageFlags},
diff --git a/ostd/src/bus/mmio/device.rs b/ostd/src/bus/mmio/device.rs
index a8992ff8..187b5ab9 100644
--- a/ostd/src/bus/mmio/device.rs
+++ b/ostd/src/bus/mmio/device.rs
@@ -7,7 +7,7 @@ use log::info;
 
 use super::VIRTIO_MMIO_MAGIC;
 use crate::{
-    io_mem::IoMem,
+    device::io_mem::IoMem,
     mm::{paddr_to_vaddr, Paddr, VmIo},
     trap::IrqLine,
 };
diff --git a/ostd/src/bus/pci/cfg_space.rs b/ostd/src/bus/pci/cfg_space.rs
index df9e1402..a3dab720 100644
--- a/ostd/src/bus/pci/cfg_space.rs
+++ b/ostd/src/bus/pci/cfg_space.rs
@@ -12,7 +12,7 @@ use bitflags::bitflags;
 use super::PciDeviceLocation;
 use crate::{
     arch::device::io_port::{PortRead, PortWrite},
-    io_mem::IoMem,
+    io::IoMem,
     mm::{
         page_prop::{CachePolicy, PageFlags},
         PodOnce, VmIoOnce,
diff --git a/ostd/src/io_mem.rs b/ostd/src/io/io_mem.rs
similarity index 100%
rename from ostd/src/io_mem.rs
rename to ostd/src/io/io_mem.rs
diff --git a/ostd/src/io/mod.rs b/ostd/src/io/mod.rs
new file mode 100644
index 00000000..63c86f8f
--- /dev/null
+++ b/ostd/src/io/mod.rs
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: MPL-2.0
+
+//! Device I/O access and corresponding allocator.
+//!
+//! This module allows device drivers to access the device I/O they need
+//! through _allocators_. There are two types of device I/O:
+//!  - `IoMem` for memory I/O (MMIO).
+//!  - `IoPort` for port I/O (PIO).
+
+mod io_mem;
+
+pub use self::io_mem::IoMem;
diff --git a/ostd/src/lib.rs b/ostd/src/lib.rs
index 45adfa17..4e7c17c2 100644
--- a/ostd/src/lib.rs
+++ b/ostd/src/lib.rs
@@ -31,8 +31,8 @@ pub mod bus;
 pub mod collections;
 pub mod console;
 pub mod cpu;
+pub mod io;
 mod error;
-pub mod io_mem;
 pub mod logger;
 pub mod mm;
 pub mod panic;