diff --git a/block/src/formats/raw/engine_aio.rs b/block/src/formats/raw/engine_aio.rs
index 49a527769..d73ac4b24 100644
--- a/block/src/formats/raw/engine_aio.rs
+++ b/block/src/formats/raw/engine_aio.rs
@@ -51,7 +51,7 @@ impl AsyncIo for RawAio {
         self.alignment
     }
 
-    fn submit_data_operation(&mut self, mut op: AsyncIoOperation) -> AsyncIoResult<()> {
+    fn submit_data_operation(&mut self, op: AsyncIoOperation) -> AsyncIoResult<()> {
         let is_read = op.is_read();
 
         if operation_is_aligned(&op, self.alignment) {
@@ -65,7 +65,7 @@ impl AsyncIo for RawAio {
             });
         }
 
-        let result = run_unaligned_operation(&self.raw_file, &mut op)?;
+        let result = run_unaligned_operation(&self.raw_file, &op)?;
         self.data_io
             .inject_completion(AsyncIoCompletion::from_operation(op, result));
 
diff --git a/block/src/formats/raw/engine_uring.rs b/block/src/formats/raw/engine_uring.rs
index 0ef2c21bd..7e1dc10df 100644
--- a/block/src/formats/raw/engine_uring.rs
+++ b/block/src/formats/raw/engine_uring.rs
@@ -48,7 +48,7 @@ impl AsyncIo for RawAsync {
         self.alignment
     }
 
-    fn submit_data_operation(&mut self, mut op: AsyncIoOperation) -> AsyncIoResult<()> {
+    fn submit_data_operation(&mut self, op: AsyncIoOperation) -> AsyncIoResult<()> {
         let is_read = op.is_read();
 
         if operation_is_aligned(&op, self.alignment) {
@@ -62,7 +62,7 @@ impl AsyncIo for RawAsync {
             });
         }
 
-        let result = run_unaligned_operation(&self.raw_file, &mut op)?;
+        let result = run_unaligned_operation(&self.raw_file, &op)?;
         self.data_io
             .inject_completion(AsyncIoCompletion::from_operation(op, result));
 
@@ -94,11 +94,11 @@ impl AsyncIo for RawAsync {
     fn submit_batch_requests(&mut self, batch_request: Vec<AsyncIoOperation>) -> AsyncIoResult<()> {
         if self.alignment != 0 {
             let mut aligned_batch = Vec::with_capacity(batch_request.len());
-            for mut op in batch_request {
+            for op in batch_request {
                 if operation_is_aligned(&op, self.alignment) {
                     aligned_batch.push(op);
                 } else {
-                    let result = run_unaligned_operation(&self.raw_file, &mut op)?;
+                    let result = run_unaligned_operation(&self.raw_file, &op)?;
                     self.data_io
                         .inject_completion(AsyncIoCompletion::from_operation(op, result));
                 }
diff --git a/block/src/formats/raw/mod.rs b/block/src/formats/raw/mod.rs
index f65573776..9aaacda23 100644
--- a/block/src/formats/raw/mod.rs
+++ b/block/src/formats/raw/mod.rs
@@ -181,22 +181,24 @@ fn operation_is_aligned(op: &AsyncIoOperation, alignment: u64) -> bool {
 /// Runs an unaligned O_DIRECT operation synchronously through `aligned_file`.
 fn run_unaligned_operation(
     aligned_file: &AlignedFile,
-    op: &mut AsyncIoOperation,
+    op: &AsyncIoOperation,
 ) -> AsyncIoResult<i32> {
     let offset = op.offset() as u64;
-    let total_len = op.total_len();
+    let iovecs = op.iovecs();
 
-    if op.is_read() {
-        let n = aligned_file
-            .read_unaligned(offset, total_len, |data| op.write_bytes_at(0, data))
-            .map_err(AsyncIoError::ReadVectored)?;
-        Ok(n as i32)
+    let n = if op.is_read() {
+        // SAFETY: op.iovecs() describes valid memory for iov_len bytes by
+        // construction of AsyncIoOperation.
+        unsafe { aligned_file.read_vectored_at(iovecs, offset) }
+            .map_err(AsyncIoError::ReadVectored)?
     } else {
-        let n = aligned_file
-            .write_unaligned(offset, total_len, |data| op.read_bytes_at(0, data))
-            .map_err(AsyncIoError::WriteVectored)?;
-        Ok(n as i32)
-    }
+        // SAFETY: op.iovecs() describes valid memory for iov_len bytes by
+        // construction of AsyncIoOperation.
+        unsafe { aligned_file.write_vectored_at(iovecs, offset) }
+            .map_err(AsyncIoError::WriteVectored)?
+    };
+
+    Ok(n as i32)
 }
 
 #[cfg(test)]