dm: Add initial device model

The device model is a user mode program which manages VM's life cycles
and handles various vmexits events. The initial version just calls exit()
syscall without doing anything else.

Signed-off-by: Vijay Dhanraj <[email protected]>
Signed-off-by: Chuanxiao Dong <[email protected]>

Cargo.toml

@@ -24,6 +24,8 @@ members = [
     "user/lib",
     # Init user-space module
     "user/init",
+    # device model module
+    "user/dm",
 ]
 
 
@@ -39,6 +41,7 @@ syscall = { path = "syscall" }
 packit = { path = "packit" }
 userlib = { path = "user/lib" }
 userinit = { path = "user/init" }
+userdm = { path = "user/dm" }
 
 # crates.io
 aes-gcm = { version = "0.10.3", default-features = false }

configs/all-targets.json

@@ -53,6 +53,9 @@
         "modules": {
             "userinit": {
                 "path": "/init"
+            },
+            "userdm": {
+                "path": "/dm"
             }
         }
     }

configs/hyperv-target.json

@@ -35,6 +35,9 @@
         "modules": {
             "userinit": {
                 "path": "/init"
+            },
+            "userdm": {
+                "path": "/dm"
             }
         }
     }

configs/qemu-target.json

@@ -34,6 +34,9 @@
         "modules": {
             "userinit": {
                 "path": "/init"
+            },
+            "userdm": {
+                "path": "/dm"
             }
         }
     }

configs/vanadium-target.json

@@ -35,6 +35,9 @@
         "modules": {
             "userinit": {
                 "path": "/init"
+            },
+            "userdm": {
+                "path": "/dm"
             }
         }
     }

user/dm/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "userdm"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+userlib.workspace = true
+
+[lints]
+workspace = true

user/dm/build.rs

@@ -0,0 +1,4 @@
+fn main() {
+    println!("cargo:rustc-link-arg=-Tuser/lib/module.lds");
+    println!("cargo:rustc-link-arg=-no-pie");
+}

user/dm/src/main.rs

@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: MIT
+//
+// Copyright (c) 2024 Intel Corporation.
+//
+// Author: Vijay Dhanraj <[email protected]>
+
+#![no_std]
+#![no_main]
+
+use userlib::*;
+
+declare_main!(main);
+
+fn main() -> u32 {
+    0
+}