agent: Remove virtio-9p storage handler

Remove the Virtio9pHandler implementation and its registration
from the storage handler manager:
(1) Remove Virtio9pHandler struct and StorageHandler implementation.
(2) Remove DRIVER_9P_TYPE and Virtio9pHandler from STORAGE_HANDLERS
  registration.
(3) Update watcher.rs comments to remove 9p references.
This completes the removal of virtio-9p support in the agent.

Signed-off-by: Alex Lyn <alex.lyn@antgroup.com>

src/agent/src/storage/fs_handler.rs

@@ -10,7 +10,7 @@ use std::sync::Arc;
 
 use crate::storage::{common_storage_handler, new_device, StorageContext, StorageHandler};
 use anyhow::{anyhow, Context, Result};
-use kata_types::device::{DRIVER_9P_TYPE, DRIVER_OVERLAYFS_TYPE, DRIVER_VIRTIOFS_TYPE};
+use kata_types::device::{DRIVER_OVERLAYFS_TYPE, DRIVER_VIRTIOFS_TYPE};
 use kata_types::mount::{StorageDevice, KATA_VOLUME_OVERLAYFS_CREATE_DIR};
 use protocols::agent::Storage;
 use tracing::instrument;
@@ -69,27 +69,6 @@ impl StorageHandler for OverlayfsHandler {
     }
 }
 
-#[derive(Debug)]
-pub struct Virtio9pHandler {}
-
-#[async_trait::async_trait]
-impl StorageHandler for Virtio9pHandler {
-    #[instrument]
-    fn driver_types(&self) -> &[&str] {
-        &[DRIVER_9P_TYPE]
-    }
-
-    #[instrument]
-    async fn create_device(
-        &self,
-        storage: Storage,
-        ctx: &mut StorageContext,
-    ) -> Result<Arc<dyn StorageDevice>> {
-        let path = common_storage_handler(ctx.logger, &storage)?;
-        new_device(path)
-    }
-}
-
 #[derive(Debug)]
 pub struct VirtioFsHandler {}
 

src/agent/src/storage/mod.rs

@@ -23,7 +23,7 @@ use tracing::instrument;
 use self::bind_watcher_handler::BindWatcherHandler;
 use self::block_handler::{PmemHandler, ScsiHandler, VirtioBlkMmioHandler, VirtioBlkPciHandler};
 use self::ephemeral_handler::EphemeralHandler;
-use self::fs_handler::{OverlayfsHandler, Virtio9pHandler, VirtioFsHandler};
+use self::fs_handler::{OverlayfsHandler, VirtioFsHandler};
 use self::image_pull_handler::ImagePullHandler;
 use self::local_handler::LocalHandler;
 use crate::mount::{baremount, is_mounted, remove_mounts};
@@ -134,7 +134,6 @@ lazy_static! {
     pub static ref STORAGE_HANDLERS: StorageHandlerManager<Arc<dyn StorageHandler>> = {
         let mut manager: StorageHandlerManager<Arc<dyn StorageHandler>> = StorageHandlerManager::new();
         let handlers: Vec<Arc<dyn StorageHandler>> = vec![
-            Arc::new(Virtio9pHandler {}),
             Arc::new(VirtioBlkMmioHandler {}),
             Arc::new(VirtioBlkPciHandler {}),
             Arc::new(EphemeralHandler {}),

src/agent/src/watcher.rs

@@ -425,7 +425,7 @@ impl SandboxStorages {
 /// or updated file to a target mount point, or remove the removed file from the target mount point.  All WatchableStorage
 /// target mount points are expected to reside within a single tmpfs, whose root is created by the BindWatcher.
 ///
-/// This is a temporary workaround to handle config map updates until we get inotify on 9p/virtio-fs.
+/// This is a temporary workaround to handle config map updates until we get inotify on virtio-fs.
 /// More context on this:
 /// - https://github.com/kata-containers/runtime/issues/1505
 /// - https://github.com/kata-containers/kata-containers/issues/1879