diff --git a/compio-driver/src/sys/fusion/op.rs b/compio-driver/src/sys/fusion/op.rs
index 115efb367..4288e2f3e 100644
--- a/compio-driver/src/sys/fusion/op.rs
+++ b/compio-driver/src/sys/fusion/op.rs
@@ -77,7 +77,7 @@ macro_rules! op {
             }
         }
 
-        impl<$($ty: $trait),*> poll::OpCode for $name<$($ty),*> {
+        unsafe impl<$($ty: $trait),*> poll::OpCode for $name<$($ty),*> {
             fn pre_submit(self: std::pin::Pin<&mut Self>) -> std::io::Result<crate::Decision> {
                 unsafe { self.map_unchecked_mut(|x| x.inner.poll() ) }.pre_submit()
             }
@@ -93,7 +93,7 @@ macro_rules! op {
             }
         }
 
-        impl<$($ty: $trait),*> iour::OpCode for $name<$($ty),*> {
+        unsafe impl<$($ty: $trait),*> iour::OpCode for $name<$($ty),*> {
             fn create_entry(self: std::pin::Pin<&mut Self>) -> OpEntry {
                 unsafe { self.map_unchecked_mut(|x| x.inner.iour() ) }.create_entry()
             }
@@ -179,7 +179,7 @@ macro_rules! mop {
             }
         }
 
-        impl<$($ty: $trait),*> poll::OpCode for $name<$($ty),*> {
+        unsafe impl<$($ty: $trait),*> poll::OpCode for $name<$($ty),*> {
             fn pre_submit(self: std::pin::Pin<&mut Self>) -> std::io::Result<crate::Decision> {
                 unsafe { self.map_unchecked_mut(|x| x.inner.poll() ) }.pre_submit()
             }
@@ -195,7 +195,7 @@ macro_rules! mop {
             }
         }
 
-        impl<$($ty: $trait),*> iour::OpCode for $name<$($ty),*> {
+        unsafe impl<$($ty: $trait),*> iour::OpCode for $name<$($ty),*> {
             fn create_entry(self: std::pin::Pin<&mut Self>) -> OpEntry {
                 unsafe { self.map_unchecked_mut(|x| x.inner.iour() ) }.create_entry()
             }
diff --git a/compio-driver/src/sys/iocp/mod.rs b/compio-driver/src/sys/iocp/mod.rs
index 205181f93..e055f3998 100644
--- a/compio-driver/src/sys/iocp/mod.rs
+++ b/compio-driver/src/sys/iocp/mod.rs
@@ -274,7 +274,12 @@ pub enum OpType {
 }
 
 /// Abstraction of IOCP operations.
-pub trait OpCode {
+///
+/// # Safety
+///
+/// Implementors must ensure that the operation is safe to be polled
+/// according to the returned [`OpType`].
+pub unsafe trait OpCode {
     /// Determines that the operation is really overlapped defined by Windows
     /// API. If not, the driver will try to operate it in another thread.
     fn op_type(&self) -> OpType {
diff --git a/compio-driver/src/sys/iocp/op.rs b/compio-driver/src/sys/iocp/op.rs
index 84a15aae8..80db5ed40 100644
--- a/compio-driver/src/sys/iocp/op.rs
+++ b/compio-driver/src/sys/iocp/op.rs
@@ -110,7 +110,7 @@ fn get_wsa_fn<F>(handle: RawFd, fguid: GUID) -> io::Result<Option<F>> {
     Ok(fptr)
 }
 
-impl<
+unsafe impl<
     D: std::marker::Send + 'static,
     F: (FnOnce() -> BufResult<usize, D>) + std::marker::Send + 'static,
 > OpCode for Asyncify<F, D>
@@ -131,7 +131,7 @@ impl<
     }
 }
 
-impl<
+unsafe impl<
     S,
     D: std::marker::Send + 'static,
     F: (FnOnce(&S) -> BufResult<usize, D>) + std::marker::Send + 'static,
@@ -154,7 +154,7 @@ impl<
     }
 }
 
-impl OpCode for CloseFile {
+unsafe impl OpCode for CloseFile {
     fn op_type(&self) -> OpType {
         OpType::Blocking
     }
@@ -166,7 +166,7 @@ impl OpCode for CloseFile {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         if let Some(overlapped) = unsafe { optr.as_mut() } {
             overlapped.Anonymous.Anonymous.Offset = (self.offset & 0xFFFFFFFF) as _;
@@ -192,7 +192,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         if let Some(overlapped) = unsafe { optr.as_mut() } {
             overlapped.Anonymous.Anonymous.Offset = (self.offset & 0xFFFFFFFF) as _;
@@ -217,7 +217,7 @@ impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
     }
 }
 
-impl<S: AsFd> OpCode for ReadManagedAt<S> {
+unsafe impl<S: AsFd> OpCode for ReadManagedAt<S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         unsafe { self.project().op.operate(optr) }
     }
@@ -227,7 +227,7 @@ impl<S: AsFd> OpCode for ReadManagedAt<S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let fd = self.fd.as_fd().as_raw_fd();
         let slice = self.project().buffer.sys_slice_mut();
@@ -249,7 +249,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let slice = self.buffer.as_init();
         let mut transferred = 0;
@@ -270,7 +270,7 @@ impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
     }
 }
 
-impl<S: AsFd> OpCode for ReadManaged<S> {
+unsafe impl<S: AsFd> OpCode for ReadManaged<S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         unsafe { self.project().op.operate(optr) }
     }
@@ -280,7 +280,7 @@ impl<S: AsFd> OpCode for ReadManaged<S> {
     }
 }
 
-impl<S: AsFd> OpCode for Sync<S> {
+unsafe impl<S: AsFd> OpCode for Sync<S> {
     fn op_type(&self) -> OpType {
         OpType::Blocking
     }
@@ -292,7 +292,7 @@ impl<S: AsFd> OpCode for Sync<S> {
     }
 }
 
-impl<S: AsFd> OpCode for ShutdownSocket<S> {
+unsafe impl<S: AsFd> OpCode for ShutdownSocket<S> {
     fn op_type(&self) -> OpType {
         OpType::Blocking
     }
@@ -309,7 +309,7 @@ impl<S: AsFd> OpCode for ShutdownSocket<S> {
     }
 }
 
-impl OpCode for CloseSocket {
+unsafe impl OpCode for CloseSocket {
     fn op_type(&self) -> OpType {
         OpType::Blocking
     }
@@ -407,7 +407,7 @@ impl<S: AsFd> Accept<S> {
     }
 }
 
-impl<S: AsFd> OpCode for Accept<S> {
+unsafe impl<S: AsFd> OpCode for Accept<S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let accept_fn = ACCEPT_EX
             .get_or_try_init(|| get_wsa_fn(self.fd.as_fd().as_raw_fd(), WSAID_ACCEPTEX))?
@@ -455,7 +455,7 @@ impl<S: AsFd> Connect<S> {
     }
 }
 
-impl<S: AsFd> OpCode for Connect<S> {
+unsafe impl<S: AsFd> OpCode for Connect<S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let connect_fn = CONNECT_EX
             .get_or_try_init(|| get_wsa_fn(self.fd.as_fd().as_raw_fd(), WSAID_CONNECTEX))?
@@ -518,7 +518,7 @@ impl<T: IoBufMut, S> IntoInner for Recv<T, S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         let fd = this.fd.as_fd().as_raw_fd();
@@ -544,7 +544,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
     }
 }
 
-impl<S: AsFd> OpCode for RecvManaged<S> {
+unsafe impl<S: AsFd> OpCode for RecvManaged<S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         unsafe { self.project().op.operate(optr) }
     }
@@ -587,7 +587,7 @@ impl<T: IoVectoredBufMut, S> IntoInner for RecvVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvVectored<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         let fd = this.fd.as_fd().as_raw_fd();
@@ -649,7 +649,7 @@ impl<T: IoBuf, S> IntoInner for Send<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         *this.slice = this.buffer.as_ref().sys_slice();
@@ -706,7 +706,7 @@ impl<T: IoVectoredBuf, S> IntoInner for SendVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for SendVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for SendVectored<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         *this.slices = this.buffer.as_ref().sys_slices();
@@ -769,7 +769,7 @@ impl<T: IoBufMut, S> IntoInner for RecvFrom<T, S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for RecvFrom<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for RecvFrom<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         let fd = this.fd.as_fd().as_raw_fd();
@@ -836,7 +836,7 @@ impl<T: IoVectoredBufMut, S> IntoInner for RecvFromVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvFromVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvFromVectored<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         let fd = this.fd.as_fd().as_raw_fd();
@@ -899,7 +899,7 @@ impl<T: IoBuf, S> IntoInner for SendTo<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for SendTo<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for SendTo<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         *this.slice = this.buffer.as_ref().sys_slice();
@@ -960,7 +960,7 @@ impl<T: IoVectoredBuf, S> IntoInner for SendToVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for SendToVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for SendToVectored<T, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
         *this.slices = this.buffer.as_ref().sys_slices();
@@ -1042,7 +1042,7 @@ impl<T: IoVectoredBufMut, C: IoBufMut, S> IntoInner for RecvMsg<T, C, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> OpCode for RecvMsg<T, C, S> {
+unsafe impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> OpCode for RecvMsg<T, C, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let recvmsg_fn = WSA_RECVMSG
             .get_or_try_init(|| get_wsa_fn(self.fd.as_fd().as_raw_fd(), WSAID_WSARECVMSG))?
@@ -1126,7 +1126,7 @@ impl<T: IoVectoredBuf, C: IoBuf, S> IntoInner for SendMsg<T, C, S> {
     }
 }
 
-impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
+unsafe impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let this = self.project();
 
@@ -1174,7 +1174,7 @@ impl<S> ConnectNamedPipe<S> {
     }
 }
 
-impl<S: AsFd> OpCode for ConnectNamedPipe<S> {
+unsafe impl<S: AsFd> OpCode for ConnectNamedPipe<S> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let res = unsafe { ConnectNamedPipe(self.fd.as_fd().as_raw_fd() as _, optr) };
         win32_result(res, 0)
@@ -1219,7 +1219,7 @@ impl<S, I: IoBuf, O: IoBufMut> IntoInner for DeviceIoControl<S, I, O> {
     }
 }
 
-impl<S: AsFd, I: IoBuf, O: IoBufMut> OpCode for DeviceIoControl<S, I, O> {
+unsafe impl<S: AsFd, I: IoBuf, O: IoBufMut> OpCode for DeviceIoControl<S, I, O> {
     unsafe fn operate(self: Pin<&mut Self>, optr: *mut OVERLAPPED) -> Poll<io::Result<usize>> {
         let mut this = self.project();
 
diff --git a/compio-driver/src/sys/iour/mod.rs b/compio-driver/src/sys/iour/mod.rs
index ff0c0568f..cc94a3de5 100644
--- a/compio-driver/src/sys/iour/mod.rs
+++ b/compio-driver/src/sys/iour/mod.rs
@@ -107,7 +107,12 @@ impl From<io_uring::squeue::Entry128> for OpEntry {
 }
 
 /// Abstraction of io-uring operations.
-pub trait OpCode {
+///
+/// # Safety
+///
+/// The returned Entry from `create_entry` must be valid until the operation is
+/// completed.
+pub unsafe trait OpCode {
     /// Create submission entry.
     fn create_entry(self: Pin<&mut Self>) -> OpEntry;
 
diff --git a/compio-driver/src/sys/iour/op.rs b/compio-driver/src/sys/iour/op.rs
index 3865b173e..f821f9744 100644
--- a/compio-driver/src/sys/iour/op.rs
+++ b/compio-driver/src/sys/iour/op.rs
@@ -18,7 +18,7 @@ use super::OpCode;
 pub use crate::sys::unix_op::*;
 use crate::{OpEntry, op::*, sys_slice::*, syscall};
 
-impl<
+unsafe impl<
     D: std::marker::Send + 'static,
     F: (FnOnce() -> BufResult<usize, D>) + std::marker::Send + 'static,
 > OpCode for Asyncify<F, D>
@@ -39,7 +39,7 @@ impl<
     }
 }
 
-impl<
+unsafe impl<
     S,
     D: std::marker::Send + 'static,
     F: (FnOnce(&S) -> BufResult<usize, D>) + std::marker::Send + 'static,
@@ -61,7 +61,7 @@ impl<
     }
 }
 
-impl OpCode for OpenFile {
+unsafe impl OpCode for OpenFile {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::OpenAt::new(Fd(libc::AT_FDCWD), self.path.as_ptr())
             .flags(self.flags | libc::O_CLOEXEC)
@@ -71,7 +71,7 @@ impl OpCode for OpenFile {
     }
 }
 
-impl OpCode for CloseFile {
+unsafe impl OpCode for CloseFile {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::Close::new(Fd(self.fd.as_fd().as_raw_fd()))
             .build()
@@ -79,7 +79,7 @@ impl OpCode for CloseFile {
     }
 }
 
-impl<S: AsFd> OpCode for TruncateFile<S> {
+unsafe impl<S: AsFd> OpCode for TruncateFile<S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         if super::is_op_supported(opcode::Ftruncate::CODE) {
             return opcode::Ftruncate::new(Fd(self.fd.as_fd().as_raw_fd()), self.size)
@@ -113,7 +113,7 @@ impl<S> FileStat<S> {
     }
 }
 
-impl<S: AsFd> OpCode for FileStat<S> {
+unsafe impl<S: AsFd> OpCode for FileStat<S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         static EMPTY_NAME: &[u8] = b"\0";
@@ -155,7 +155,7 @@ impl PathStat {
     }
 }
 
-impl OpCode for PathStat {
+unsafe impl OpCode for PathStat {
     fn create_entry(mut self: Pin<&mut Self>) -> OpEntry {
         let mut flags = libc::AT_EMPTY_PATH;
         if !self.follow_symlink {
@@ -181,7 +181,7 @@ impl IntoInner for PathStat {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         let fd = Fd(this.fd.as_fd().as_raw_fd());
@@ -197,7 +197,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectoredAt<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectoredAt<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         *this.slices = this.buffer.sys_slices_mut();
@@ -212,7 +212,7 @@ impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectoredAt<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let slice = self.buffer.as_init();
         opcode::Write::new(
@@ -226,7 +226,7 @@ impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectoredAt<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectoredAt<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         *this.slices = this.buffer.as_ref().sys_slices();
@@ -241,7 +241,7 @@ impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectoredAt<T, S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let fd = self.fd.as_fd().as_raw_fd();
         let slice = self.project().buffer.sys_slice_mut();
@@ -255,7 +255,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectored<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         *this.slices = this.buffer.sys_slices_mut();
@@ -269,7 +269,7 @@ impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectored<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let slice = self.buffer.as_init();
         opcode::Write::new(
@@ -282,7 +282,7 @@ impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectored<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         *this.slices = this.buffer.as_ref().sys_slices();
@@ -296,7 +296,7 @@ impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectored<T, S> {
     }
 }
 
-impl<S: AsFd> OpCode for Sync<S> {
+unsafe impl<S: AsFd> OpCode for Sync<S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::Fsync::new(Fd(self.fd.as_fd().as_raw_fd()))
             .flags(if self.datasync {
@@ -309,7 +309,7 @@ impl<S: AsFd> OpCode for Sync<S> {
     }
 }
 
-impl OpCode for Unlink {
+unsafe impl OpCode for Unlink {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::UnlinkAt::new(Fd(libc::AT_FDCWD), self.path.as_ptr())
             .flags(if self.dir { libc::AT_REMOVEDIR } else { 0 })
@@ -318,7 +318,7 @@ impl OpCode for Unlink {
     }
 }
 
-impl OpCode for CreateDir {
+unsafe impl OpCode for CreateDir {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::MkDirAt::new(Fd(libc::AT_FDCWD), self.path.as_ptr())
             .mode(self.mode)
@@ -327,7 +327,7 @@ impl OpCode for CreateDir {
     }
 }
 
-impl OpCode for Rename {
+unsafe impl OpCode for Rename {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::RenameAt::new(
             Fd(libc::AT_FDCWD),
@@ -340,7 +340,7 @@ impl OpCode for Rename {
     }
 }
 
-impl OpCode for Symlink {
+unsafe impl OpCode for Symlink {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::SymlinkAt::new(
             Fd(libc::AT_FDCWD),
@@ -352,7 +352,7 @@ impl OpCode for Symlink {
     }
 }
 
-impl OpCode for HardLink {
+unsafe impl OpCode for HardLink {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::LinkAt::new(
             Fd(libc::AT_FDCWD),
@@ -365,7 +365,7 @@ impl OpCode for HardLink {
     }
 }
 
-impl OpCode for CreateSocket {
+unsafe impl OpCode for CreateSocket {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         if super::is_op_supported(opcode::Socket::CODE) {
             opcode::Socket::new(
@@ -389,7 +389,7 @@ impl OpCode for CreateSocket {
     }
 }
 
-impl<S: AsFd> OpCode for ShutdownSocket<S> {
+unsafe impl<S: AsFd> OpCode for ShutdownSocket<S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::Shutdown::new(Fd(self.fd.as_fd().as_raw_fd()), self.how())
             .build()
@@ -397,7 +397,7 @@ impl<S: AsFd> OpCode for ShutdownSocket<S> {
     }
 }
 
-impl OpCode for CloseSocket {
+unsafe impl OpCode for CloseSocket {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::Close::new(Fd(self.fd.as_fd().as_raw_fd()))
             .build()
@@ -405,7 +405,7 @@ impl OpCode for CloseSocket {
     }
 }
 
-impl<S: AsFd> OpCode for Accept<S> {
+unsafe impl<S: AsFd> OpCode for Accept<S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         opcode::Accept::new(
@@ -425,7 +425,7 @@ impl<S: AsFd> OpCode for Accept<S> {
     }
 }
 
-impl<S: AsFd> OpCode for Connect<S> {
+unsafe impl<S: AsFd> OpCode for Connect<S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::Connect::new(
             Fd(self.fd.as_fd().as_raw_fd()),
@@ -437,7 +437,7 @@ impl<S: AsFd> OpCode for Connect<S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let fd = self.fd.as_fd().as_raw_fd();
         let flags = self.flags;
@@ -453,7 +453,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvVectored<T, S> {
     fn create_entry(mut self: Pin<&mut Self>) -> OpEntry {
         self.as_mut().set_msg();
         let this = self.project();
@@ -464,7 +464,7 @@ impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvVectored<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let slice = self.buffer.as_init();
         opcode::Send::new(
@@ -478,7 +478,7 @@ impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for SendVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for SendVectored<T, S> {
     fn create_entry(mut self: Pin<&mut Self>) -> OpEntry {
         self.as_mut().set_msg();
         let this = self.project();
@@ -547,7 +547,7 @@ impl<T: IoBufMut, S> RecvFrom<T, S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for RecvFrom<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for RecvFrom<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         let slice = this.slice.insert(this.buffer.sys_slice_mut());
@@ -585,7 +585,7 @@ impl<T: IoVectoredBufMut, S> RecvFromVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvFromVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvFromVectored<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         *this.slice = this.buffer.sys_slices_mut();
@@ -656,7 +656,7 @@ impl<T: IoBuf, S> SendTo<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for SendTo<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for SendTo<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         let slice = this.slice.insert(this.buffer.as_ref().sys_slice());
@@ -693,7 +693,7 @@ impl<T: IoVectoredBuf, S> SendToVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for SendToVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for SendToVectored<T, S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let this = self.project();
         *this.slice = this.buffer.as_ref().sys_slices();
@@ -709,7 +709,7 @@ impl<T: IoVectoredBuf, S> IntoInner for SendToVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> OpCode for RecvMsg<T, C, S> {
+unsafe impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> OpCode for RecvMsg<T, C, S> {
     fn create_entry(mut self: Pin<&mut Self>) -> OpEntry {
         self.as_mut().set_msg();
         let this = self.project();
@@ -720,7 +720,7 @@ impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> OpCode for RecvMsg<T, C, S> {
     }
 }
 
-impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
+unsafe impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
     fn create_entry(mut self: Pin<&mut Self>) -> OpEntry {
         self.as_mut().set_msg();
         let this = self.project();
@@ -731,7 +731,7 @@ impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
     }
 }
 
-impl<S: AsFd> OpCode for PollOnce<S> {
+unsafe impl<S: AsFd> OpCode for PollOnce<S> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         let flags = match self.interest {
             Interest::Readable => libc::POLLIN,
@@ -743,7 +743,7 @@ impl<S: AsFd> OpCode for PollOnce<S> {
     }
 }
 
-impl<S1: AsFd, S2: AsFd> OpCode for Splice<S1, S2> {
+unsafe impl<S1: AsFd, S2: AsFd> OpCode for Splice<S1, S2> {
     fn create_entry(self: Pin<&mut Self>) -> OpEntry {
         opcode::Splice::new(
             Fd(self.fd_in.as_fd().as_raw_fd()),
@@ -799,7 +799,7 @@ mod buf_ring {
         }
     }
 
-    impl<S: AsFd> OpCode for ReadManagedAt<S> {
+    unsafe impl<S: AsFd> OpCode for ReadManagedAt<S> {
         fn create_entry(self: Pin<&mut Self>) -> OpEntry {
             let fd = Fd(self.fd.as_fd().as_raw_fd());
             let offset = self.offset;
@@ -857,7 +857,7 @@ mod buf_ring {
         }
     }
 
-    impl<S: AsFd> OpCode for ReadManaged<S> {
+    unsafe impl<S: AsFd> OpCode for ReadManaged<S> {
         fn create_entry(self: Pin<&mut Self>) -> OpEntry {
             let fd = self.fd.as_fd().as_raw_fd();
             opcode::Read::new(Fd(fd), ptr::null_mut(), self.len)
@@ -915,7 +915,7 @@ mod buf_ring {
         }
     }
 
-    impl<S: AsFd> OpCode for RecvManaged<S> {
+    unsafe impl<S: AsFd> OpCode for RecvManaged<S> {
         fn create_entry(self: Pin<&mut Self>) -> OpEntry {
             let fd = self.fd.as_fd().as_raw_fd();
             opcode::Recv::new(Fd(fd), ptr::null_mut(), self.len)
diff --git a/compio-driver/src/sys/poll/mod.rs b/compio-driver/src/sys/poll/mod.rs
index e0a5f8235..2bea99528 100644
--- a/compio-driver/src/sys/poll/mod.rs
+++ b/compio-driver/src/sys/poll/mod.rs
@@ -42,13 +42,13 @@ impl From<WaitArg> for Track {
 
 /// Abstraction of operations.
 ///
-/// # Implementation notes
+/// # Safety
 ///
 /// If `pre_submit` returns `Decision::Wait`, `op_type` must also return
 /// `Some(OpType::Fd)` with same fds as the `WaitArg`s. Similarly, if
 /// `pre_submit` returns `Decision::Aio`, `op_type` must return
 /// `Some(OpType::Aio)` with the correct `aiocb` pointer.
-pub trait OpCode {
+pub unsafe trait OpCode {
     /// Perform the operation before submit, and return [`Decision`] to
     /// indicate whether submitting the operation to polling is required.
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision>;
diff --git a/compio-driver/src/sys/poll/op.rs b/compio-driver/src/sys/poll/op.rs
index c1f6617ad..c1e5c4876 100644
--- a/compio-driver/src/sys/poll/op.rs
+++ b/compio-driver/src/sys/poll/op.rs
@@ -25,7 +25,7 @@ use super::{AsFd, Decision, OpCode, OpType, syscall};
 pub use crate::sys::unix_op::*;
 use crate::{op::*, sys_slice::*};
 
-impl<
+unsafe impl<
     D: std::marker::Send + 'static,
     F: (FnOnce() -> BufResult<usize, D>) + std::marker::Send + 'static,
 > OpCode for Asyncify<F, D>
@@ -46,7 +46,7 @@ impl<
     }
 }
 
-impl<
+unsafe impl<
     S,
     D: std::marker::Send + 'static,
     F: (FnOnce(&S) -> BufResult<usize, D>) + std::marker::Send + 'static,
@@ -68,7 +68,7 @@ impl<
     }
 }
 
-impl OpCode for OpenFile {
+unsafe impl OpCode for OpenFile {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -82,7 +82,7 @@ impl OpCode for OpenFile {
     }
 }
 
-impl OpCode for CloseFile {
+unsafe impl OpCode for CloseFile {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -92,7 +92,7 @@ impl OpCode for CloseFile {
     }
 }
 
-impl<S: AsFd> OpCode for TruncateFile<S> {
+unsafe impl<S: AsFd> OpCode for TruncateFile<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -120,7 +120,7 @@ impl<S> FileStat<S> {
     }
 }
 
-impl<S: AsFd> OpCode for FileStat<S> {
+unsafe impl<S: AsFd> OpCode for FileStat<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -176,7 +176,7 @@ impl PathStat {
     }
 }
 
-impl OpCode for PathStat {
+unsafe impl OpCode for PathStat {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -219,7 +219,7 @@ impl IntoInner for PathStat {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         #[cfg(aio)]
         {
@@ -252,7 +252,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for ReadAt<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectoredAt<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectoredAt<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         #[cfg(freebsd)]
         {
@@ -291,7 +291,7 @@ impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectoredAt<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         #[cfg(aio)]
         {
@@ -329,7 +329,7 @@ impl<T: IoBuf, S: AsFd> OpCode for WriteAt<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectoredAt<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectoredAt<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         #[cfg(freebsd)]
         {
@@ -368,7 +368,7 @@ impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectoredAt<T, S> {
     }
 }
 
-impl<S: AsFd> OpCode for crate::op::managed::ReadManagedAt<S> {
+unsafe impl<S: AsFd> OpCode for crate::op::managed::ReadManagedAt<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         self.project().op.pre_submit()
     }
@@ -382,7 +382,7 @@ impl<S: AsFd> OpCode for crate::op::managed::ReadManagedAt<S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::wait_readable(self.fd.as_fd().as_raw_fd()))
     }
@@ -398,7 +398,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for Read<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectored<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::wait_readable(self.fd.as_fd().as_raw_fd()))
     }
@@ -420,7 +420,7 @@ impl<T: IoVectoredBufMut, S: AsFd> OpCode for ReadVectored<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::wait_writable(self.fd.as_fd().as_raw_fd()))
     }
@@ -441,7 +441,7 @@ impl<T: IoBuf, S: AsFd> OpCode for Write<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectored<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::wait_writable(self.fd.as_fd().as_raw_fd()))
     }
@@ -463,7 +463,7 @@ impl<T: IoVectoredBuf, S: AsFd> OpCode for WriteVectored<T, S> {
     }
 }
 
-impl<S: AsFd> OpCode for crate::op::managed::ReadManaged<S> {
+unsafe impl<S: AsFd> OpCode for crate::op::managed::ReadManaged<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         self.project().op.pre_submit()
     }
@@ -477,7 +477,7 @@ impl<S: AsFd> OpCode for crate::op::managed::ReadManaged<S> {
     }
 }
 
-impl<S: AsFd> OpCode for Sync<S> {
+unsafe impl<S: AsFd> OpCode for Sync<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         #[cfg(aio)]
         {
@@ -526,7 +526,7 @@ impl<S: AsFd> OpCode for Sync<S> {
     }
 }
 
-impl OpCode for Unlink {
+unsafe impl OpCode for Unlink {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -541,7 +541,7 @@ impl OpCode for Unlink {
     }
 }
 
-impl OpCode for CreateDir {
+unsafe impl OpCode for CreateDir {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -552,7 +552,7 @@ impl OpCode for CreateDir {
     }
 }
 
-impl OpCode for Rename {
+unsafe impl OpCode for Rename {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -563,7 +563,7 @@ impl OpCode for Rename {
     }
 }
 
-impl OpCode for Symlink {
+unsafe impl OpCode for Symlink {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -574,7 +574,7 @@ impl OpCode for Symlink {
     }
 }
 
-impl OpCode for HardLink {
+unsafe impl OpCode for HardLink {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -645,7 +645,7 @@ impl CreateSocket {
     }
 }
 
-impl OpCode for CreateSocket {
+unsafe impl OpCode for CreateSocket {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -655,7 +655,7 @@ impl OpCode for CreateSocket {
     }
 }
 
-impl<S: AsFd> OpCode for ShutdownSocket<S> {
+unsafe impl<S: AsFd> OpCode for ShutdownSocket<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -667,7 +667,7 @@ impl<S: AsFd> OpCode for ShutdownSocket<S> {
     }
 }
 
-impl OpCode for CloseSocket {
+unsafe impl OpCode for CloseSocket {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::Blocking)
     }
@@ -727,7 +727,7 @@ impl<S: AsFd> Accept<S> {
     }
 }
 
-impl<S: AsFd> OpCode for Accept<S> {
+unsafe impl<S: AsFd> OpCode for Accept<S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         let fd = self.fd.as_fd().as_raw_fd();
         syscall!(self.as_mut().call(), wait_readable(fd))
@@ -748,7 +748,7 @@ impl<S: AsFd> OpCode for Accept<S> {
     }
 }
 
-impl<S: AsFd> OpCode for Connect<S> {
+unsafe impl<S: AsFd> OpCode for Connect<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         syscall!(
             libc::connect(
@@ -785,7 +785,7 @@ impl<S: AsFd> OpCode for Connect<S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::wait_readable(self.fd.as_fd().as_raw_fd()))
     }
@@ -802,7 +802,7 @@ impl<T: IoBufMut, S: AsFd> OpCode for Recv<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::wait_writable(self.fd.as_fd().as_raw_fd()))
     }
@@ -824,7 +824,7 @@ impl<T: IoBuf, S: AsFd> OpCode for Send<T, S> {
     }
 }
 
-impl<S: AsFd> OpCode for crate::op::managed::RecvManaged<S> {
+unsafe impl<S: AsFd> OpCode for crate::op::managed::RecvManaged<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         self.project().op.pre_submit()
     }
@@ -845,7 +845,7 @@ impl<T: IoVectoredBufMut, S: AsFd> RecvVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvVectored<T, S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         self.as_mut().set_msg();
         let fd = self.fd.as_fd().as_raw_fd();
@@ -867,7 +867,7 @@ impl<T: IoVectoredBuf, S: AsFd> SendVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for SendVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for SendVectored<T, S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         self.as_mut().set_msg();
         let fd = self.as_mut().project().fd.as_fd().as_raw_fd();
@@ -930,7 +930,7 @@ impl<T: IoBufMut, S: AsFd> RecvFrom<T, S> {
     }
 }
 
-impl<T: IoBufMut, S: AsFd> OpCode for RecvFrom<T, S> {
+unsafe impl<T: IoBufMut, S: AsFd> OpCode for RecvFrom<T, S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         let fd = self.fd.as_fd().as_raw_fd();
         syscall!(self.as_mut().call(), wait_readable(fd))
@@ -998,7 +998,7 @@ impl<T: IoVectoredBufMut, S: AsFd> RecvFromVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvFromVectored<T, S> {
+unsafe impl<T: IoVectoredBufMut, S: AsFd> OpCode for RecvFromVectored<T, S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         self.as_mut().set_msg();
         let fd = self.as_mut().project().fd.as_fd().as_raw_fd();
@@ -1062,7 +1062,7 @@ impl<T: IoBuf, S: AsFd> SendTo<T, S> {
     }
 }
 
-impl<T: IoBuf, S: AsFd> OpCode for SendTo<T, S> {
+unsafe impl<T: IoBuf, S: AsFd> OpCode for SendTo<T, S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         syscall!(self.call(), wait_writable(self.fd.as_fd().as_raw_fd()))
     }
@@ -1128,7 +1128,7 @@ impl<T: IoVectoredBuf, S: AsFd> SendToVectored<T, S> {
     }
 }
 
-impl<T: IoVectoredBuf, S: AsFd> OpCode for SendToVectored<T, S> {
+unsafe impl<T: IoVectoredBuf, S: AsFd> OpCode for SendToVectored<T, S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         self.as_mut().set_msg();
         let fd = self.fd.as_fd().as_raw_fd();
@@ -1159,7 +1159,7 @@ impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> RecvMsg<T, C, S> {
     }
 }
 
-impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> OpCode for RecvMsg<T, C, S> {
+unsafe impl<T: IoVectoredBufMut, C: IoBufMut, S: AsFd> OpCode for RecvMsg<T, C, S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         self.as_mut().set_msg();
         let fd = self.fd.as_fd().as_raw_fd();
@@ -1181,7 +1181,7 @@ impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> SendMsg<T, C, S> {
     }
 }
 
-impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
+unsafe impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
     fn pre_submit(mut self: Pin<&mut Self>) -> io::Result<Decision> {
         self.as_mut().set_msg();
         let fd = self.fd.as_fd().as_raw_fd();
@@ -1197,7 +1197,7 @@ impl<T: IoVectoredBuf, C: IoBuf, S: AsFd> OpCode for SendMsg<T, C, S> {
     }
 }
 
-impl<S: AsFd> OpCode for PollOnce<S> {
+unsafe impl<S: AsFd> OpCode for PollOnce<S> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         Ok(Decision::wait_for(
             self.fd.as_fd().as_raw_fd(),
@@ -1215,7 +1215,7 @@ impl<S: AsFd> OpCode for PollOnce<S> {
 }
 
 #[cfg(linux_all)]
-impl<S1: AsFd, S2: AsFd> OpCode for Splice<S1, S2> {
+unsafe impl<S1: AsFd, S2: AsFd> OpCode for Splice<S1, S2> {
     fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
         use super::WaitArg;
 
diff --git a/compio-driver/tests/splice.rs b/compio-driver/tests/splice.rs
index 9ee5cb2fc..9a6b85ca9 100644
--- a/compio-driver/tests/splice.rs
+++ b/compio-driver/tests/splice.rs
@@ -79,7 +79,7 @@ mod splice_impl {
         }
     }
 
-    impl<S1: AsFd, S2: AsFd> OpCode for Splice<S1, S2> {
+    unsafe impl<S1: AsFd, S2: AsFd> OpCode for Splice<S1, S2> {
         fn pre_submit(self: Pin<&mut Self>) -> io::Result<Decision> {
             Ok(Decision::wait_for_many([
                 WaitArg::readable(self.fd_in.as_fd().as_raw_fd()),
diff --git a/compio-fs/src/stdio/windows.rs b/compio-fs/src/stdio/windows.rs
index f54208dac..424b81eaf 100644
--- a/compio-fs/src/stdio/windows.rs
+++ b/compio-fs/src/stdio/windows.rs
@@ -29,7 +29,7 @@ impl<R: Read, B: IoBufMut> StdRead<R, B> {
     }
 }
 
-impl<R: Read, B: IoBufMut> OpCode for StdRead<R, B> {
+unsafe impl<R: Read, B: IoBufMut> OpCode for StdRead<R, B> {
     fn op_type(&self) -> OpType {
         OpType::Blocking
     }
@@ -80,7 +80,7 @@ impl<W: Write, B: IoBuf> StdWrite<W, B> {
     }
 }
 
-impl<W: Write, B: IoBuf> OpCode for StdWrite<W, B> {
+unsafe impl<W: Write, B: IoBuf> OpCode for StdWrite<W, B> {
     fn op_type(&self) -> OpType {
         OpType::Blocking
     }
diff --git a/compio-net/src/poll_fd/windows.rs b/compio-net/src/poll_fd/windows.rs
index 01b99bc86..4c47e6852 100644
--- a/compio-net/src/poll_fd/windows.rs
+++ b/compio-net/src/poll_fd/windows.rs
@@ -197,7 +197,7 @@ impl<T> IntoInner for WaitWSAEvent<T> {
     }
 }
 
-impl<T: AsFd> OpCode for WaitWSAEvent<T> {
+unsafe impl<T: AsFd> OpCode for WaitWSAEvent<T> {
     fn op_type(&self) -> OpType {
         OpType::Event(self.ev_object.as_raw_fd())
     }
diff --git a/compio-process/src/windows.rs b/compio-process/src/windows.rs
index 91285cb0d..0aa42b51f 100644
--- a/compio-process/src/windows.rs
+++ b/compio-process/src/windows.rs
@@ -28,7 +28,7 @@ impl WaitProcess {
     }
 }
 
-impl OpCode for WaitProcess {
+unsafe impl OpCode for WaitProcess {
     fn op_type(&self) -> OpType {
         OpType::Event(self.child.as_raw_handle() as _)
     }
diff --git a/compio-runtime/tests/event.rs b/compio-runtime/tests/event.rs
index 9c51f1d3c..3a805fcb0 100644
--- a/compio-runtime/tests/event.rs
+++ b/compio-runtime/tests/event.rs
@@ -35,7 +35,7 @@ fn win32_event() {
         event: OwnedHandle,
     }
 
-    impl OpCode for WaitEvent {
+    unsafe impl OpCode for WaitEvent {
         fn op_type(&self) -> OpType {
             OpType::Event(self.event.as_raw_handle() as _)
         }