From c347f84d748e1ee927a144a48ca48cf2e1e99794 Mon Sep 17 00:00:00 2001
From: Yang Zhong <yang.zhong@intel.com>
Date: Wed, 11 Sep 2019 13:50:34 +0800
Subject: [PATCH] Revert "vhost_rs: add config messge support"

This reverts commit 3e99098bf34fe77b7f6d296adacfe07ca16c4f1b because we
realized there was no need for those extra functions to be introduced as
the existing one from the vhost crate are sufficient for the vhost-user
configuration use case.
---
 vhost_rs/src/vhost_user/connection.rs | 39 ---------------------------
 vhost_rs/src/vhost_user/master.rs     | 25 ++---------------
 2 files changed, 2 insertions(+), 62 deletions(-)

diff --git a/vhost_rs/src/vhost_user/connection.rs b/vhost_rs/src/vhost_user/connection.rs
index f0f28c98c..69439dd70 100644
--- a/vhost_rs/src/vhost_user/connection.rs
+++ b/vhost_rs/src/vhost_user/connection.rs
@@ -197,45 +197,6 @@ impl<R: Req> Endpoint<R> {
         Ok(())
     }
 
-    /// Send a message with header, body and config info. Optional file descriptors may be attached to
-    /// the message.
-    ///
-    /// # Return:
-    /// * - number of bytes sent on success
-    /// * - SocketRetry: temporary error caused by signals or short of resources.
-    /// * - SocketBroken: the underline socket is broken.
-    /// * - SocketError: other socket related errors.
-    /// * - PartialMessage: received a partial message.
-    pub fn send_config_message(
-        &mut self,
-        hdr: &VhostUserMsgHeader<R>,
-        user_config: &VhostUserConfig,
-        buf: &mut [u8],
-        fds: Option<&[RawFd]>,
-    ) -> Result<()> {
-        // Safe because there can't be other mutable referance to hdr and body.
-        let iovs = unsafe {
-            [
-                slice::from_raw_parts(
-                    hdr as *const VhostUserMsgHeader<R> as *const u8,
-                    mem::size_of::<VhostUserMsgHeader<R>>(),
-                ),
-                slice::from_raw_parts(
-                    user_config as *const VhostUserConfig as *const u8,
-                    mem::size_of::<VhostUserConfig>(),
-                ),
-                slice::from_raw_parts(buf.as_ptr() as *const u8, buf.len()),
-            ]
-        };
-        let bytes = self.send_iovec(&iovs[..], fds)?;
-        let total =
-            mem::size_of::<VhostUserMsgHeader<R>>() + mem::size_of::<VhostUserConfig>() + buf.len();
-        if bytes != total {
-            return Err(Error::PartialMessage);
-        }
-        Ok(())
-    }
-
     /// Send a message with header, body and payload. Optional file descriptors
     /// may also be attached to the message.
     ///
diff --git a/vhost_rs/src/vhost_user/master.rs b/vhost_rs/src/vhost_user/master.rs
index 28b6e99fd..a7129a18d 100644
--- a/vhost_rs/src/vhost_user/master.rs
+++ b/vhost_rs/src/vhost_user/master.rs
@@ -360,7 +360,7 @@ impl VhostUserMaster for Master {
         // "Master payload: virtio device config space"
         // But what content should the payload contains for a get_config() request?
         // So current implementation doesn't conform to the spec.
-        let hdr = node.send_request_with_config_body(MasterReq::GET_CONFIG, &body, None)?;
+        let hdr = node.send_request_with_body(MasterReq::GET_CONFIG, &body, None)?;
         let (reply, buf, rfds) = node.recv_reply_with_payload::<VhostUserConfig>(&hdr)?;
         if rfds.is_some() {
             Endpoint::<MasterReq>::close_rfds(rfds);
@@ -480,27 +480,6 @@ impl MasterInternal {
         Ok(hdr)
     }
 
-    fn send_request_with_config_body(
-        &mut self,
-        code: MasterReq,
-        user_config: &VhostUserConfig,
-        fds: Option<&[RawFd]>,
-    ) -> VhostUserResult<VhostUserMsgHeader<MasterReq>> {
-        if mem::size_of::<VhostUserConfig>() + user_config.size as usize > MAX_MSG_SIZE {
-            return Err(VhostUserError::InvalidParam);
-        }
-        self.check_state()?;
-
-        let hdr = Self::new_request_header(
-            code,
-            mem::size_of::<VhostUserConfig>() as u32 + user_config.size,
-        );
-        let mut buf = vec![0; user_config.size as usize];
-        self.main_sock
-            .send_config_message(&hdr, user_config, &mut buf, fds)?;
-        Ok(hdr)
-    }
-
     fn send_request_with_payload<T: Sized, P: Sized>(
         &mut self,
         code: MasterReq,
@@ -576,7 +555,7 @@ impl MasterInternal {
         if !reply.is_reply_for(hdr)
             || reply.get_size() as usize != mem::size_of::<T>() + bytes
             || rfds.is_some()
-            || !body.is_valid()
+            || body.is_valid()
         {
             Endpoint::<MasterReq>::close_rfds(rfds);
             return Err(VhostUserError::InvalidMessage);