diff --git a/actix-http/src/header/shared/charset.rs b/actix-http/src/header/shared/charset.rs
index b482f6bce..3cc0f3e23 100644
--- a/actix-http/src/header/shared/charset.rs
+++ b/actix-http/src/header/shared/charset.rs
@@ -88,7 +88,7 @@ impl Charset {
             Iso_8859_8_E => "ISO-8859-8-E",
             Iso_8859_8_I => "ISO-8859-8-I",
             Gb2312 => "GB2312",
-            Big5 => "big5",
+            Big5 => "Big5",
             Koi8_R => "KOI8-R",
             Ext(ref s) => s,
         }
@@ -128,7 +128,7 @@ impl FromStr for Charset {
             "ISO-8859-8-E" => Iso_8859_8_E,
             "ISO-8859-8-I" => Iso_8859_8_I,
             "GB2312" => Gb2312,
-            "big5" => Big5,
+            "BIG5" => Big5,
             "KOI8-R" => Koi8_R,
             s => Ext(s.to_owned()),
         })
diff --git a/actix-multipart/Cargo.toml b/actix-multipart/Cargo.toml
index b1dea4832..5376ba128 100644
--- a/actix-multipart/Cargo.toml
+++ b/actix-multipart/Cargo.toml
@@ -20,7 +20,6 @@ actix-utils = "3.0.0"
 bytes = "1"
 derive_more = "0.99.5"
 futures-core = { version = "0.3.7", default-features = false, features = ["alloc"] }
-futures-util = { version = "0.3.7", default-features = false, features = ["alloc"] }
 httparse = "1.3"
 local-waker = "0.1"
 log = "0.4"
@@ -30,5 +29,6 @@ twoway = "0.2"
 [dev-dependencies]
 actix-rt = "2.2"
 actix-http = "3.0.0-beta.13"
+futures-util = { version = "0.3.7", default-features = false, features = ["alloc"] }
 tokio = { version = "1", features = ["sync"] }
 tokio-stream = "0.1"
diff --git a/actix-multipart/src/server.rs b/actix-multipart/src/server.rs
index 43f9ccf5f..c9642cfad 100644
--- a/actix-multipart/src/server.rs
+++ b/actix-multipart/src/server.rs
@@ -17,7 +17,6 @@ use actix_web::{
 };
 use bytes::{Bytes, BytesMut};
 use futures_core::stream::{LocalBoxStream, Stream};
-use futures_util::stream::StreamExt as _;
 use local_waker::LocalWaker;
 
 use crate::error::MultipartError;
@@ -33,7 +32,7 @@ const MAX_HEADERS: usize = 32;
 pub struct Multipart {
     safety: Safety,
     error: Option<MultipartError>,
-    inner: Option<Rc<RefCell<InnerMultipart>>>,
+    inner: Option<InnerMultipart>,
 }
 
 enum InnerMultipartItem {
@@ -67,7 +66,7 @@ impl Multipart {
     /// Create multipart instance for boundary.
     pub fn new<S>(headers: &HeaderMap, stream: S) -> Multipart
     where
-        S: Stream<Item = Result<Bytes, PayloadError>> + Unpin + 'static,
+        S: Stream<Item = Result<Bytes, PayloadError>> + 'static,
     {
         match Self::boundary(headers) {
             Ok(boundary) => Multipart::from_boundary(boundary, stream),
@@ -77,39 +76,32 @@ impl Multipart {
 
     /// Extract boundary info from headers.
     pub(crate) fn boundary(headers: &HeaderMap) -> Result<String, MultipartError> {
-        if let Some(content_type) = headers.get(&header::CONTENT_TYPE) {
-            if let Ok(content_type) = content_type.to_str() {
-                if let Ok(ct) = content_type.parse::<mime::Mime>() {
-                    if let Some(boundary) = ct.get_param(mime::BOUNDARY) {
-                        Ok(boundary.as_str().to_owned())
-                    } else {
-                        Err(MultipartError::Boundary)
-                    }
-                } else {
-                    Err(MultipartError::ParseContentType)
-                }
-            } else {
-                Err(MultipartError::ParseContentType)
-            }
-        } else {
-            Err(MultipartError::NoContentType)
-        }
+        headers
+            .get(&header::CONTENT_TYPE)
+            .ok_or(MultipartError::NoContentType)?
+            .to_str()
+            .ok()
+            .and_then(|content_type| content_type.parse::<mime::Mime>().ok())
+            .ok_or(MultipartError::ParseContentType)?
+            .get_param(mime::BOUNDARY)
+            .map(|boundary| boundary.as_str().to_owned())
+            .ok_or(MultipartError::Boundary)
     }
 
     /// Create multipart instance for given boundary and stream
     pub(crate) fn from_boundary<S>(boundary: String, stream: S) -> Multipart
     where
-        S: Stream<Item = Result<Bytes, PayloadError>> + Unpin + 'static,
+        S: Stream<Item = Result<Bytes, PayloadError>> + 'static,
     {
         Multipart {
             error: None,
             safety: Safety::new(),
-            inner: Some(Rc::new(RefCell::new(InnerMultipart {
+            inner: Some(InnerMultipart {
                 boundary,
-                payload: PayloadRef::new(PayloadBuffer::new(Box::new(stream))),
+                payload: PayloadRef::new(PayloadBuffer::new(stream)),
                 state: InnerState::FirstBoundary,
                 item: InnerMultipartItem::None,
-            }))),
+            }),
         }
     }
 
@@ -126,20 +118,27 @@ impl Multipart {
 impl Stream for Multipart {
     type Item = Result<Field, MultipartError>;
 
-    fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
-        if let Some(err) = self.error.take() {
-            Poll::Ready(Some(Err(err)))
-        } else if self.safety.current() {
-            let this = self.get_mut();
-            let mut inner = this.inner.as_mut().unwrap().borrow_mut();
-            if let Some(mut payload) = inner.payload.get_mut(&this.safety) {
-                payload.poll_stream(cx)?;
+    fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        let this = self.get_mut();
+
+        match this.inner.as_mut() {
+            Some(inner) => {
+                if let Some(mut buffer) = inner.payload.get_mut(&this.safety) {
+                    // check safety and poll read payload to buffer.
+                    buffer.poll_stream(cx)?;
+                } else if !this.safety.is_clean() {
+                    // safety violation
+                    return Poll::Ready(Some(Err(MultipartError::NotConsumed)));
+                } else {
+                    return Poll::Pending;
+                }
+
+                inner.poll(&this.safety, cx)
             }
-            inner.poll(&this.safety, cx)
-        } else if !self.safety.is_clean() {
-            Poll::Ready(Some(Err(MultipartError::NotConsumed)))
-        } else {
-            Poll::Pending
+            None => Poll::Ready(Some(Err(this
+                .error
+                .take()
+                .expect("Multipart polled after finish")))),
         }
     }
 }
@@ -160,17 +159,15 @@ impl InnerMultipart {
                     Ok(httparse::Status::Complete((_, hdrs))) => {
                         // convert headers
                         let mut headers = HeaderMap::with_capacity(hdrs.len());
+
                         for h in hdrs {
-                            if let Ok(name) = HeaderName::try_from(h.name) {
-                                if let Ok(value) = HeaderValue::try_from(h.value) {
-                                    headers.append(name, value);
-                                } else {
-                                    return Err(ParseError::Header.into());
-                                }
-                            } else {
-                                return Err(ParseError::Header.into());
-                            }
+                            let name =
+                                HeaderName::try_from(h.name).map_err(|_| ParseError::Header)?;
+                            let value = HeaderValue::try_from(h.value)
+                                .map_err(|_| ParseError::Header)?;
+                            headers.append(name, value);
                         }
+
                         Ok(Some(headers))
                     }
                     Ok(httparse::Status::Partial) => Err(ParseError::Header.into()),
@@ -466,17 +463,19 @@ impl Stream for Field {
     type Item = Result<Bytes, MultipartError>;
 
     fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
-        if self.safety.current() {
-            let mut inner = self.inner.borrow_mut();
-            if let Some(mut payload) = inner.payload.as_ref().unwrap().get_mut(&self.safety) {
-                payload.poll_stream(cx)?;
-            }
-            inner.poll(&self.safety)
-        } else if !self.safety.is_clean() {
-            Poll::Ready(Some(Err(MultipartError::NotConsumed)))
+        let this = self.get_mut();
+        let mut inner = this.inner.borrow_mut();
+        if let Some(mut buffer) = inner.payload.as_ref().unwrap().get_mut(&this.safety) {
+            // check safety and poll read payload to buffer.
+            buffer.poll_stream(cx)?;
+        } else if !this.safety.is_clean() {
+            // safety violation
+            return Poll::Ready(Some(Err(MultipartError::NotConsumed)));
         } else {
-            Poll::Pending
+            return Poll::Pending;
         }
+
+        inner.poll(&this.safety)
     }
 }
 
@@ -690,10 +689,7 @@ impl PayloadRef {
         }
     }
 
-    fn get_mut<'a, 'b>(&'a self, s: &'b Safety) -> Option<RefMut<'a, PayloadBuffer>>
-    where
-        'a: 'b,
-    {
+    fn get_mut(&self, s: &Safety) -> Option<RefMut<'_, PayloadBuffer>> {
         if s.current() {
             Some(self.payload.borrow_mut())
         } else {
@@ -779,7 +775,7 @@ impl PayloadBuffer {
         PayloadBuffer {
             eof: false,
             buf: BytesMut::new(),
-            stream: stream.boxed_local(),
+            stream: Box::pin(stream),
         }
     }
 
@@ -860,7 +856,7 @@ mod tests {
     use actix_web::test::TestRequest;
     use actix_web::FromRequest;
     use bytes::Bytes;
-    use futures_util::future::lazy;
+    use futures_util::{future::lazy, StreamExt};
     use tokio::sync::mpsc;
     use tokio_stream::wrappers::UnboundedReceiverStream;