Add qcow2 support

src/qemu.rs

@@ -5,7 +5,10 @@ use anyhow::{Context, Result, bail};
 use clap::Args;
 use std::process::Command;
 
-use crate::registry::registry_dir;
+use crate::{
+    meta::Meta,
+    registry::{registry_base_dir, registry_dir},
+};
 
 #[derive(Args, Debug)]
 pub struct RunCmd {
@@ -19,14 +22,38 @@ pub struct RunCmd {
 
 pub(crate) fn run(RunCmd { name, memory }: RunCmd) -> Result<()> {
     let reg_dir = registry_dir(&name)?;
-    let vmlinuz_path = reg_dir.join("vmlinuz");
+    let vmlinuz_path = registry_base_dir()?.join("vmlinuz");
     let initrd_path = reg_dir.join("initrd");
-    if !vmlinuz_path.exists() || !initrd_path.exists() {
-        bail!(
-            "Registry missing vmlinuz/initrd for '{}'. Run `slim build` first.",
-            name
-        );
+    let qcow2_path = reg_dir.join("image.qcow2");
+    if !vmlinuz_path.exists() {
+        // TODO: guide user in how to set up a kernel
+        bail!("No kernel available.")
     }
+
+    let meta = Meta::load(&name).context("Failed to load meta.toml. Run `slim build` first.")?;
+    // TODO: sanity-check for spaces
+    let init_arg = format!("init={}", meta.init);
+
+    let fs_args;
+    let mut cmdline = vec![
+        "console=ttyS0,115200",
+        "rw",
+        "earlyprintk=serial",
+        "nokaslr",
+        &init_arg,
+    ];
+
+    let qcow2_arg = format!("file={},format=qcow2,if=virtio", qcow2_path.display());
+    if qcow2_path.exists() {
+        fs_args = vec!["-drive", &qcow2_arg];
+        cmdline.extend_from_slice(&["root=/dev/vda", "rootfstype=ext4"]);
+    } else if initrd_path.exists() {
+        fs_args = vec!["-initrd", initrd_path.to_str().context("Invalid UTF-8")?];
+        cmdline.push("root=/dev/ram0");
+    } else {
+        bail!("Registry missing rootfs/initrd for '{name}'. Run `slim build` first.");
+    }
+
     println!("Booting {name} from registry: {}", reg_dir.display());
     println!(
         "  qemu-system-x86_64 -m 256 -nographic -kernel {} -initrd {} -append 'console=ttyS0'",
@@ -34,23 +61,14 @@ pub(crate) fn run(RunCmd { name, memory }: RunCmd) -> Result<()> {
         initrd_path.display()
     );
 
-    let cmdline = [
-        "console=ttyS0,115200",
-        "root=/dev/ram0",
-        "rw",
-        "earlyprintk=serial",
-        "nokaslr",
-        "raid=noautodetect",
-    ]
-    .join(" ");
+    let cmdline = cmdline.join(" ");
 
     let mut command = Command::new("qemu-system-x86_64");
     command
         .args(["-m", &memory])
         .arg("-kernel")
         .arg(vmlinuz_path.as_os_str())
-        .arg("-initrd")
-        .arg(initrd_path.as_os_str())
+        .args(fs_args)
         .args(["-append", &cmdline])
         .args(["-nographic"])
         .args(["-nic", "user,model=virtio-net-pci"]);