virtiofs: add mount options to resource (#416)

Add mount options to the virtiofs resource.

Allow the virtiofs mount options to be provided on the command line. To
make this work cleanly, change the `:` separator to `,`.

Guide/src/reference/openvmm/management/cli.md

@@ -20,7 +20,7 @@ as well as the generated CLI help (via `cargo run -- --help`).
 * `--virtio-console`: Enables a virtio serial device (via the MMIO transport) for Linux console access instead of COM1.
 * `--virtio-console-pci`: Uses the PCI transport for the virtio serial console.
 * `--gfx`: Enable a graphical console over VNC (see below)
-* `--virtio-9p`: Expose a virtio 9p file system. Uses the format `tag:root_path`, e.g. `myfs:C:\\`.
+* `--virtio-9p`: Expose a virtio 9p file system. Uses the format `tag,root_path`, e.g. `myfs,C:\\`.
   The file system can be mounted in a Linux guest using `mount -t 9p  -o trans=virtio tag /mnt/point`.
   You can specify this argument multiple times to create multiple file systems.
 * `--virtio-fs`: Expose a virtio-fs file system. The format is the same as `--virtio-9p`. The

openvmm/openvmm_entry/src/cli_args.rs

@@ -316,21 +316,21 @@ flags:
     #[clap(long, requires("igvm"), default_value = "auto=filesize", value_parser = parse_vtl2_relocation)]
     pub igvm_vtl2_relocation_type: Vtl2BaseAddressType,
 
-    /// add a virtio_9p device (e.g. myfs:C:\)
-    #[clap(long, value_name = "tag:root_path", value_parser = parse_fs_arg)]
-    pub virtio_9p: Vec<(String, String)>,
+    /// add a virtio_9p device (e.g. myfs,C:\)
+    #[clap(long, value_name = "tag,root_path")]
+    pub virtio_9p: Vec<FsArgs>,
 
     /// output debug info from the 9p server
     #[clap(long)]
     pub virtio_9p_debug: bool,
 
-    /// add a virtio_fs device (e.g. myfs:C:\)
-    #[clap(long, value_name = "tag:root_path", value_parser = parse_fs_arg)]
-    pub virtio_fs: Vec<(String, String)>,
+    /// add a virtio_fs device (e.g. myfs,C:\,uid=1000,gid=2000)
+    #[clap(long, value_name = "tag,root_path,[options]")]
+    pub virtio_fs: Vec<FsArgsWithOptions>,
 
-    /// add a virtio_fs device for sharing memory (e.g. myfs:\SectionDirectoryPath)
-    #[clap(long, value_name = "tag:root_path", value_parser = parse_fs_arg)]
-    pub virtio_fs_shmem: Vec<(String, String)>,
+    /// add a virtio_fs device for sharing memory (e.g. myfs,\SectionDirectoryPath)
+    #[clap(long, value_name = "tag,root_path")]
+    pub virtio_fs_shmem: Vec<FsArgs>,
 
     /// add a virtio_fs device under either the PCI or MMIO bus, or whatever the hypervisor supports (pci | mmio | auto)
     #[clap(long, value_name = "BUS", default_value = "auto")]
@@ -525,9 +525,52 @@ flags:
     pub uefi_console_mode: Option<UefiConsoleModeCli>,
 }
 
-fn parse_fs_arg(opt: &str) -> Result<(String, String), &'static str> {
-    let (tag, root_path) = opt.split_once(':').ok_or("invalid value")?;
-    Ok((tag.to_owned(), root_path.to_owned()))
+#[derive(Clone)]
+pub struct FsArgs {
+    pub tag: String,
+    pub path: String,
+}
+
+impl FromStr for FsArgs {
+    type Err = anyhow::Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let mut s = s.split(',');
+        let (Some(tag), Some(path), None) = (s.next(), s.next(), s.next()) else {
+            anyhow::bail!("expected <tag>,<path>");
+        };
+        Ok(Self {
+            tag: tag.to_owned(),
+            path: path.to_owned(),
+        })
+    }
+}
+
+#[derive(Clone)]
+pub struct FsArgsWithOptions {
+    /// The file system tag.
+    pub tag: String,
+    /// The root path.
+    pub path: String,
+    /// The extra options, joined with ';'.
+    pub options: String,
+}
+
+impl FromStr for FsArgsWithOptions {
+    type Err = anyhow::Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let mut s = s.split(',');
+        let (Some(tag), Some(path)) = (s.next(), s.next()) else {
+            anyhow::bail!("expected <tag>,<path>[,<options>]");
+        };
+        let options = s.collect::<Vec<_>>().join(";");
+        Ok(Self {
+            tag: tag.to_owned(),
+            path: path.to_owned(),
+            options,
+        })
+    }
 }
 
 #[derive(Copy, Clone, clap::ValueEnum)]

openvmm/openvmm_entry/src/lib.rs

@@ -1172,38 +1172,39 @@ fn vm_config_from_command_line(
         );
     }
 
-    for (tag, root_path) in &opt.virtio_fs {
+    for args in &opt.virtio_fs {
         add_virtio_device(
             opt.virtio_fs_bus,
             virtio_resources::fs::VirtioFsHandle {
-                tag: tag.clone(),
+                tag: args.tag.clone(),
                 fs: virtio_resources::fs::VirtioFsBackend::HostFs {
-                    root_path: root_path.clone(),
+                    root_path: args.path.clone(),
+                    mount_options: args.options.clone(),
                 },
             }
             .into_resource(),
         );
     }
 
-    for (tag, root_path) in &opt.virtio_fs_shmem {
+    for args in &opt.virtio_fs_shmem {
         add_virtio_device(
             opt.virtio_fs_bus,
             virtio_resources::fs::VirtioFsHandle {
-                tag: tag.clone(),
+                tag: args.tag.clone(),
                 fs: virtio_resources::fs::VirtioFsBackend::SectionFs {
-                    root_path: root_path.clone(),
+                    root_path: args.path.clone(),
                 },
             }
             .into_resource(),
         );
     }
 
-    for (tag, root_path) in &opt.virtio_9p {
+    for args in &opt.virtio_9p {
         add_virtio_device(
             VirtioBusCli::Auto,
             virtio_resources::p9::VirtioPlan9Handle {
-                tag: tag.clone(),
-                root_path: root_path.clone(),
+                tag: args.tag.clone(),
+                root_path: args.path.clone(),
                 debug: opt.virtio_9p_debug,
             }
             .into_resource(),

openvmm/openvmm_entry/src/ttrpc/mod.rs

@@ -546,6 +546,7 @@ impl VmService {
                     tag: virtiofs.tag,
                     fs: virtio_resources::fs::VirtioFsBackend::HostFs {
                         root_path: virtiofs.root_path,
+                        mount_options: String::new(),
                     },
                 }
                 .into_resource();

vm/devices/virtio/virtio_resources/src/lib.rs

@@ -52,8 +52,13 @@ pub mod fs {
 
     #[derive(MeshPayload)]
     pub enum VirtioFsBackend {
-        HostFs { root_path: String },
-        SectionFs { root_path: String },
+        HostFs {
+            root_path: String,
+            mount_options: String,
+        },
+        SectionFs {
+            root_path: String,
+        },
     }
 
     impl ResourceId<VirtioDeviceHandle> for VirtioFsHandle {

vm/devices/virtio/virtiofs/src/resolver.rs

@@ -5,6 +5,7 @@
 
 use crate::virtio::VirtioFsDevice;
 use crate::VirtioFs;
+use lxutil::LxVolumeOptions;
 use virtio::resolve::ResolvedVirtioDevice;
 use virtio::resolve::VirtioResolveInput;
 use virtio_resources::fs::VirtioFsBackend;
@@ -31,10 +32,16 @@ impl ResolveResource<VirtioDeviceHandle, VirtioFsHandle> for VirtioFsResolver {
         input: VirtioResolveInput<'_>,
     ) -> Result<Self::Output, Self::Error> {
         let device = match &resource.fs {
-            VirtioFsBackend::HostFs { root_path } => VirtioFsDevice::new(
+            VirtioFsBackend::HostFs {
+                root_path,
+                mount_options,
+            } => VirtioFsDevice::new(
                 input.driver_source,
                 &resource.tag,
-                VirtioFs::new(root_path, None)?,
+                VirtioFs::new(
+                    root_path,
+                    Some(&LxVolumeOptions::from_option_string(mount_options)),
+                )?,
                 input.guest_memory.clone(),
                 0,
                 None,