diff --git a/crates/librqbit/src/storage/filesystem/fs.rs b/crates/librqbit/src/storage/filesystem/fs.rs
index 36e57ab..6232aa9 100644
--- a/crates/librqbit/src/storage/filesystem/fs.rs
+++ b/crates/librqbit/src/storage/filesystem/fs.rs
@@ -1,9 +1,14 @@
 use std::{
     fs::OpenOptions,
-    io::{Read, Seek, SeekFrom, Write},
     path::{Path, PathBuf},
 };
 
+#[cfg(not(target_family = "unix"))]
+use std::io::{Read, Seek, SeekFrom, Write};
+
+#[cfg(target_family = "unix")]
+use std::os::unix::fs::FileExt;
+
 use anyhow::Context;
 
 use crate::{storage::StorageFactoryExt, torrent_state::ManagedTorrentInfo};
@@ -85,25 +90,31 @@ impl FilesystemStorage {
 
 impl TorrentStorage for FilesystemStorage {
     fn pread_exact(&self, file_id: usize, offset: u64, buf: &mut [u8]) -> anyhow::Result<()> {
-        let mut g = self
-            .opened_files
-            .get(file_id)
-            .context("no such file")?
-            .file
-            .lock();
-        g.seek(SeekFrom::Start(offset))?;
-        Ok(g.read_exact(buf)?)
+        let of = self.opened_files.get(file_id).context("no such file")?;
+        #[cfg(target_family = "unix")]
+        {
+            Ok(of.file.read().read_exact_at(buf, offset)?)
+        }
+        #[cfg(not(target_family = "unix"))]
+        {
+            let mut g = of.file.write();
+            g.seek(SeekFrom::Start(offset))?;
+            Ok(g.read_exact(buf)?)
+        }
     }
 
     fn pwrite_all(&self, file_id: usize, offset: u64, buf: &[u8]) -> anyhow::Result<()> {
-        let mut g = self
-            .opened_files
-            .get(file_id)
-            .context("no such file")?
-            .file
-            .lock();
-        g.seek(SeekFrom::Start(offset))?;
-        Ok(g.write_all(buf)?)
+        let of = self.opened_files.get(file_id).context("no such file")?;
+        #[cfg(target_family = "unix")]
+        {
+            Ok(of.file.read().write_all_at(buf, offset)?)
+        }
+        #[cfg(not(target_family = "unix"))]
+        {
+            let mut g = of.file.write();
+            g.seek(SeekFrom::Start(offset))?;
+            Ok(g.write_all(buf)?)
+        }
     }
 
     fn remove_file(&self, _file_id: usize, filename: &Path) -> anyhow::Result<()> {
@@ -111,7 +122,7 @@ impl TorrentStorage for FilesystemStorage {
     }
 
     fn ensure_file_length(&self, file_id: usize, len: u64) -> anyhow::Result<()> {
-        Ok(self.opened_files[file_id].file.lock().set_len(len)?)
+        Ok(self.opened_files[file_id].file.write().set_len(len)?)
     }
 
     fn take(&self) -> anyhow::Result<Box<dyn TorrentStorage>> {
diff --git a/crates/librqbit/src/storage/filesystem/mmap.rs b/crates/librqbit/src/storage/filesystem/mmap.rs
index 731db70..e5ef44a 100644
--- a/crates/librqbit/src/storage/filesystem/mmap.rs
+++ b/crates/librqbit/src/storage/filesystem/mmap.rs
@@ -26,7 +26,7 @@ impl StorageFactory for MmapFilesystemStorageFactory {
         let fs_storage = FilesystemStorageFactory::default().init_storage(meta)?;
         let mut mmaps = Vec::new();
         for file in fs_storage.opened_files.iter() {
-            let mmap = unsafe { MmapOptions::new().map_mut(&*file.file.lock()) }
+            let mmap = unsafe { MmapOptions::new().map_mut(&*file.file.read()) }
                 .context("error mapping file")?;
             mmaps.push(RwLock::new(mmap));
         }
diff --git a/crates/librqbit/src/storage/filesystem/opened_file.rs b/crates/librqbit/src/storage/filesystem/opened_file.rs
index b7a3cca..88f24dd 100644
--- a/crates/librqbit/src/storage/filesystem/opened_file.rs
+++ b/crates/librqbit/src/storage/filesystem/opened_file.rs
@@ -1,11 +1,11 @@
 use std::fs::File;
 
 use anyhow::Context;
-use parking_lot::Mutex;
+use parking_lot::RwLock;
 
 #[derive(Debug)]
 pub(crate) struct OpenedFile {
-    pub file: Mutex<File>,
+    pub file: RwLock<File>,
 }
 
 pub(crate) fn dummy_file() -> anyhow::Result<std::fs::File> {
@@ -23,12 +23,12 @@ pub(crate) fn dummy_file() -> anyhow::Result<std::fs::File> {
 impl OpenedFile {
     pub fn new(f: File) -> Self {
         Self {
-            file: Mutex::new(f),
+            file: RwLock::new(f),
         }
     }
 
     pub fn take(&self) -> anyhow::Result<File> {
-        let mut f = self.file.lock();
+        let mut f = self.file.write();
         let dummy = dummy_file()?;
         let f = std::mem::replace(&mut *f, dummy);
         Ok(f)
@@ -37,7 +37,7 @@ impl OpenedFile {
     pub fn take_clone(&self) -> anyhow::Result<Self> {
         let f = self.take()?;
         Ok(Self {
-            file: Mutex::new(f),
+            file: RwLock::new(f),
         })
     }
 }