vmm: Add support for multiple virtio-fs devices

Until now, the VMM was only accepting a single instance of a virtio-fs
device. This commit extend the virtio-fs support by allowing several
devices to be created for a single VM.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

src/main.rs

@@ -74,7 +74,8 @@ fn main() {
                      sock=<socket_path>,num_queues=<number_of_queues>,\
                      queue_size=<size_of_each_queue>\"",
                 )
-                .takes_value(true),
+                .takes_value(true)
+                .min_values(1),
         )
         .get_matches();
 
@@ -98,7 +99,7 @@ fn main() {
     // This .unwrap() cannot fail as there is a default value defined
     let rng = cmd_arguments.value_of("rng").unwrap();
 
-    let fs = cmd_arguments.value_of("fs");
+    let fs: Option<Vec<&str>> = cmd_arguments.values_of("fs").map(|x| x.collect());
 
     let vm_config = match config::VmConfig::parse(config::VmParams {
         cpus,

vmm/src/config.rs

@@ -59,7 +59,7 @@ pub struct VmParams<'a> {
     pub disks: Vec<&'a str>,
     pub net: Option<&'a str>,
     pub rng: &'a str,
-    pub fs: Option<&'a str>,
+    pub fs: Option<Vec<&'a str>>,
 }
 
 pub struct CpusConfig(pub u8);
@@ -232,6 +232,7 @@ impl<'a> RngConfig<'a> {
     }
 }
 
+#[derive(Debug)]
 pub struct FsConfig<'a> {
     pub tag: &'a str,
     pub sock: &'a Path,
@@ -240,13 +241,9 @@ pub struct FsConfig<'a> {
 }
 
 impl<'a> FsConfig<'a> {
-    pub fn parse(fs: Option<&'a str>) -> Result<Option<Self>> {
-        if fs.is_none() {
-            return Ok(None);
-        }
-
+    pub fn parse(fs: &'a str) -> Result<Self> {
         // Split the parameters based on the comma delimiter
-        let params_list: Vec<&str> = fs.unwrap().split(',').collect();
+        let params_list: Vec<&str> = fs.split(',').collect();
 
         let mut tag: &str = "";
         let mut sock: &str = "";
@@ -285,12 +282,12 @@ impl<'a> FsConfig<'a> {
                 .map_err(Error::ParseFsQueueSizeParam)?;
         }
 
-        Ok(Some(FsConfig {
+        Ok(FsConfig {
             tag,
             sock: Path::new(sock),
             num_queues,
             queue_size,
-        }))
+        })
     }
 }
 
@@ -302,7 +299,7 @@ pub struct VmConfig<'a> {
     pub disks: Vec<DiskConfig<'a>>,
     pub net: Option<NetConfig<'a>>,
     pub rng: RngConfig<'a>,
-    pub fs: Option<FsConfig<'a>>,
+    pub fs: Option<Vec<FsConfig<'a>>>,
 }
 
 impl<'a> VmConfig<'a> {
@@ -312,6 +309,15 @@ impl<'a> VmConfig<'a> {
             disks.push(DiskConfig::parse(disk)?);
         }
 
+        let mut fs: Option<Vec<FsConfig>> = None;
+        if let Some(fs_list) = &vm_params.fs {
+            let mut fs_config_list = Vec::new();
+            for item in fs_list.iter() {
+                fs_config_list.push(FsConfig::parse(item)?);
+            }
+            fs = Some(fs_config_list);
+        }
+
         Ok(VmConfig {
             cpus: CpusConfig::parse(vm_params.cpus)?,
             memory: MemoryConfig::parse(vm_params.memory)?,
@@ -320,7 +326,7 @@ impl<'a> VmConfig<'a> {
             disks,
             net: NetConfig::parse(vm_params.net)?,
             rng: RngConfig::parse(vm_params.rng)?,
-            fs: FsConfig::parse(vm_params.fs)?,
+            fs,
         })
     }
 }

vmm/src/vm.rs

@@ -595,10 +595,16 @@ impl DeviceManager {
         }
 
         // Add virtio-fs if required
-        if let Some(fs_cfg) = &vm_cfg.fs {
+        if let Some(fs_list_cfg) = &vm_cfg.fs {
+            for fs_cfg in fs_list_cfg.iter() {
+                println!("####VIRTIO-FS config {:?}", fs_cfg);
                 if let Some(fs_sock) = fs_cfg.sock.to_str() {
-                let virtio_fs_device =
-                    vm_virtio::Fs::new(fs_sock, fs_cfg.tag, fs_cfg.num_queues, fs_cfg.queue_size)
+                    let virtio_fs_device = vm_virtio::Fs::new(
+                        fs_sock,
+                        fs_cfg.tag,
+                        fs_cfg.num_queues,
+                        fs_cfg.queue_size,
+                    )
                     .map_err(DeviceManagerError::CreateVirtioFs)?;
 
                     DeviceManager::add_virtio_pci_device(
@@ -612,6 +618,7 @@ impl DeviceManager {
                     )?;
                 }
             }
+        }
 
         let pci = Arc::new(Mutex::new(PciConfigIo::new(pci_root)));