Basic x112virtgpu support

crates/muvm/src/bin/muvm.rs

@@ -287,7 +287,7 @@ fn main() -> Result<()> {
 
     // Forward the native X11 display into the guest as a socket
     if let Ok(x11_display) = env::var("DISPLAY") {
-        if let Some(x11_display) = x11_display.strip_prefix(":") {
+        if let Some(x11_display) = x11_display.strip_prefix(':') {
             let socket_path = Path::new("/tmp/.X11-unix/").join(format!("X{}", x11_display));
             if socket_path.exists() {
                 let socket_path = CString::new(
@@ -361,6 +361,18 @@ fn main() -> Result<()> {
         options.server_port.to_string(),
     );
 
+    if options.direct_x11 {
+        let display =
+            env::var("DISPLAY").context("X11 forwarding requested but DISPLAY is unset")?;
+        env.insert("HOST_DISPLAY".to_string(), display);
+
+        // And forward XAUTHORITY. This will be modified to fix the
+        // display name in muvm-guest.
+        if let Ok(xauthority) = env::var("XAUTHORITY") {
+            env.insert("XAUTHORITY".to_string(), xauthority);
+        }
+    }
+
     let mut krun_config = KrunConfig {
         args: Vec::new(),
         envs: Vec::new(),

crates/muvm/src/cli_options.rs

@@ -15,6 +15,7 @@ pub struct Options {
     pub passt_socket: Option<PathBuf>,
     pub server_port: u32,
     pub fex_images: Vec<String>,
+    pub direct_x11: bool,
     pub command: PathBuf,
     pub command_args: Vec<String>,
 }
@@ -98,6 +99,11 @@ pub fn options() -> OptionParser<Options> {
         .argument("SERVER_PORT")
         .fallback(3334)
         .display_fallback();
+    let direct_x11 = long("direct-x11")
+        .short('x')
+        .help("Use direct X11 forwarding instead of sommelier + XWayland")
+        .switch();
+
     let command = positional("COMMAND").help("the command you want to execute in the vm");
     let command_args = any::<String, _, _>("COMMAND_ARGS", |arg| {
         (!["--help", "-h"].contains(&&*arg)).then_some(arg)
@@ -113,6 +119,7 @@ pub fn options() -> OptionParser<Options> {
         passt_socket,
         server_port,
         fex_images,
+        direct_x11,
         // positionals
         command,
         command_args,

crates/muvm/src/env.rs

@@ -64,19 +64,6 @@ pub fn prepare_env_vars(env: Vec<(String, Option<String>)>) -> Result<HashMap<St
         env_map.insert(key, value);
     }
 
-    // If we have an X11 display in the host, set HOST_DISPLAY in the guest.
-    // muvm-guest will then use this to set up xauth and replace it with :1
-    // (which is forwarded to the host display).
-    if let Ok(display) = env::var("DISPLAY") {
-        env_map.insert("HOST_DISPLAY".to_string(), display);
-
-        // And forward XAUTHORITY. This will be modified to fix the
-        // display name in muvm-guest.
-        if let Ok(xauthority) = env::var("XAUTHORITY") {
-            env_map.insert("XAUTHORITY".to_string(), xauthority);
-        }
-    }
-
     debug!(env:? = env_map; "env vars");
 
     Ok(env_map)

crates/muvm/src/guest/bin/muvm-guest.rs

@@ -61,13 +61,13 @@ fn main() -> Result<()> {
     let pulse_path = pulse_path.join("native");
     setup_socket_proxy(pulse_path, 3333)?;
 
-    setup_x11_forwarding(run_path)?;
-
-    // Will not return if successful.
-    exec_sommelier(&options.command, &options.command_args)
-        .context("Failed to execute sommelier")?;
+    if !setup_x11_forwarding(run_path)? {
+        // Will not return if successful.
+        exec_sommelier(&options.command, &options.command_args)
+            .context("Failed to execute sommelier")?;
+    }
 
-    // Fallback option if sommelier is not present.
+    // Fallback option if sommelier is not present or for direct X11 mode.
     debug!(command:? = options.command, command_args:? = options.command_args; "exec");
     let err = Command::new(&options.command)
         .args(options.command_args)

crates/muvm/src/guest/x11.rs

@@ -2,34 +2,47 @@ use std::env;
 use std::fs::File;
 use std::io::{Read, Write};
 use std::path::Path;
+use std::process::Command;
 
 use anyhow::{anyhow, Context, Result};
 use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
 
 use super::socket::setup_socket_proxy;
 
-pub fn setup_x11_forwarding<P>(run_path: P) -> Result<()>
+use crate::utils::env::find_in_path;
+
+pub fn setup_x11_forwarding<P>(run_path: P) -> Result<bool>
 where
     P: AsRef<Path>,
 {
     // Set by muvm if DISPLAY was provided from the host.
     let host_display = match env::var("HOST_DISPLAY") {
         Ok(d) => d,
-        Err(_) => return Ok(()),
+        Err(_) => return Ok(false),
     };
 
-    if !host_display.starts_with(":") {
+    if !host_display.starts_with(':') {
         return Err(anyhow!("Invalid host DISPLAY"));
     }
     let host_display = &host_display[1..];
 
-    setup_socket_proxy(Path::new("/tmp/.X11-unix/X1"), 6000)?;
+    let x112virtgpu_path =
+        find_in_path("x112virtgpu").context("Failed to check existence of `x112virtgpu`")?;
+
+    if x112virtgpu_path.is_some() {
+        let mut cmd = Command::new(x112virtgpu_path.unwrap());
+        cmd.args(["--listen-display", ":1"]);
+
+        cmd.spawn().context("Failed to spawn `x112virtgpu`")?;
+    } else {
+        log::error!("x112virtgpu not available, X11 forwarding will operate in socket forwarding mode. This is probably not what you want.");
+        setup_socket_proxy(Path::new("/tmp/.X11-unix/X1"), 6000)?;
+    }
 
-    // Set HOST_DISPLAY to :1, which is the display number within the guest
-    // at which the actual host display is accessible.
     // SAFETY: Safe if and only if `muvm-guest` program is not multithreaded.
     // See https://doc.rust-lang.org/std/env/fn.set_var.html#safety
-    env::set_var("HOST_DISPLAY", ":1");
+    env::set_var("DISPLAY", ":1");
+    env::set_var("XSHMFENCE_NO_MEMFD", "1");
 
     if let Ok(xauthority) = std::env::var("XAUTHORITY") {
         let src_path = format!("/run/muvm-host/{}", xauthority);
@@ -87,5 +100,5 @@ where
         env::set_var("XAUTHORITY", dst_path);
     }
 
-    Ok(())
+    Ok(true)
 }