disks: Add discovery of virtual devices (/dev/vd*)

We've used the name `virt` because `virtual` is reserved.

Signed-off-by: Ikey Doherty <[email protected]>

crates/disks/src/disk.rs

@@ -9,7 +9,7 @@ use std::{
     path::{Path, PathBuf},
 };
 
-use crate::{mmc, nvme, partition::Partition, scsi, sysfs, DEVFS_DIR};
+use crate::{mmc, nvme, partition::Partition, scsi, sysfs, virt, DEVFS_DIR};
 
 /// Represents the type of disk device.
 #[derive(Debug)]
@@ -20,6 +20,8 @@ pub enum Disk {
     Mmc(mmc::Disk),
     /// NVMe disk device (e.g. nvme0n1)
     Nvme(nvme::Disk),
+    /// Virtual disk device
+    Virtual(virt::Disk),
 }
 
 impl Deref for Disk {
@@ -31,6 +33,7 @@ impl Deref for Disk {
             Disk::Mmc(disk) => disk,
             Disk::Nvme(disk) => disk,
             Disk::Scsi(disk) => disk,
+            Disk::Virtual(disk) => disk,
         }
     }
 }

crates/disks/src/lib.rs

@@ -15,6 +15,7 @@ pub mod nvme;
 pub mod partition;
 pub mod scsi;
 mod sysfs;
+pub mod virt;
 
 const SYSFS_DIR: &str = "/sys/class/block";
 const DEVFS_DIR: &str = "/dev";
@@ -83,6 +84,8 @@ impl BlockDevice {
                 BlockDevice::Disk(Box::new(Disk::Nvme(disk)))
             } else if let Some(disk) = mmc::Disk::from_sysfs_path(&sysfs_dir, &entry) {
                 BlockDevice::Disk(Box::new(Disk::Mmc(disk)))
+            } else if let Some(device) = virt::Disk::from_sysfs_path(&sysfs_dir, &entry) {
+                BlockDevice::Disk(Box::new(Disk::Virtual(device)))
             } else if let Some(device) = loopback::Device::from_sysfs_path(&sysfs_dir, &entry) {
                 BlockDevice::Loopback(Box::new(device))
             } else {

crates/disks/src/virt.rs

@@ -0,0 +1,49 @@
+// SPDX-FileCopyrightText: Copyright © 2025 Serpent OS Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+//! Virtual disk device enumeration and handling.
+//!
+//! In Linux systems, virtual disk devices are exposed through
+//! the block subsystem. This module handles enumeration and management of these devices,
+//! which appear as `/dev/vd*` block devices.
+
+use std::{ops::Deref, path::Path};
+
+use crate::{BasicDisk, DiskInit};
+
+/// Represents a virtual disk device.
+///
+/// This struct wraps a BasicDisk to provide virtual disk-specific functionality.
+#[derive(Debug)]
+pub struct Disk(pub BasicDisk);
+
+impl Deref for Disk {
+    type Target = BasicDisk;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl DiskInit for Disk {
+    /// Creates a new Disk instance from a sysfs path if the device name matches virtual disk naming pattern.
+    ///
+    /// # Arguments
+    ///
+    /// * `sysroot` - The root path of the sysfs filesystem
+    /// * `name` - The device name to check (e.g. "vda", "vdb")
+    ///
+    /// # Returns
+    ///
+    /// * `Some(Disk)` if the name matches virtual disk pattern (starts with "vd" followed by letters)
+    /// * `None` if the name doesn't match or the device can't be initialized
+    fn from_sysfs_path(sysroot: &Path, name: &str) -> Option<Self> {
+        let matching = name.starts_with("vd") && name[2..].chars().all(char::is_alphabetic);
+        if matching {
+            Some(Self(BasicDisk::from_sysfs_path(sysroot, name)?))
+        } else {
+            None
+        }
+    }
+}