refactor(virtio): change to consts

Signed-off-by: Changyuan Lyu <changyuanl@google.com>

Author: Lencerf

alioth/src/virtio/dev/balloon.rs

@@ -190,7 +190,7 @@ impl Virtio for Balloon {
     type Feature = BalloonFeature;
 
     fn id(&self) -> DeviceId {
-        DeviceId::Balloon
+        DeviceId::BALLOON
     }
 
     fn name(&self) -> &str {

alioth/src/virtio/dev/blk.rs

@@ -285,7 +285,7 @@ impl Virtio for Block {
     type Feature = BlockFeature;
 
     fn id(&self) -> DeviceId {
-        DeviceId::Block
+        DeviceId::BLOCK
     }
 
     fn name(&self) -> &str {

alioth/src/virtio/dev/entropy.rs

@@ -85,7 +85,7 @@ impl Virtio for Entropy {
     type Feature = EntropyFeature;
 
     fn id(&self) -> DeviceId {
-        DeviceId::Entropy
+        DeviceId::ENTROPY
     }
 
     fn name(&self) -> &str {

alioth/src/virtio/dev/entropy_test.rs

@@ -72,7 +72,7 @@ fn entropy_test(fixture_ram_bus: RamBus, fixture_queues: Box<[QueueReg]>) {
     };
     let dev = param.build("entropy").unwrap();
 
-    assert_matches!(dev.id(), DeviceId::Entropy);
+    assert_matches!(dev.id(), DeviceId::ENTROPY);
     assert_eq!(dev.name(), "entropy");
     assert_eq!(dev.num_queues(), 1);
     assert_matches!(*dev.config(), EntropyConfig);

alioth/src/virtio/dev/fs/fs.rs

@@ -399,7 +399,7 @@ where
     type Feature = FsFeature;
 
     fn id(&self) -> DeviceId {
-        DeviceId::FileSystem
+        DeviceId::FILE_SYSTEM
     }
 
     fn name(&self) -> &str {

alioth/src/virtio/dev/net/vmnet.rs

@@ -236,7 +236,7 @@ impl Virtio for Net {
     type Feature = NetFeature;
 
     fn id(&self) -> DeviceId {
-        DeviceId::Net
+        DeviceId::NET
     }
 
     fn name(&self) -> &str {

alioth/src/virtio/dev/vsock/uds_vsock.rs

@@ -695,7 +695,7 @@ impl Virtio for UdsVsock {
     type Feature = VsockFeature;
 
     fn id(&self) -> DeviceId {
-        DeviceId::Socket
+        DeviceId::SOCKET
     }
 
     fn name(&self) -> &str {

alioth/src/virtio/dev/vsock/uds_vsock_test.rs

@@ -124,7 +124,7 @@ fn vsock_conn_test(fixture_ram_bus: RamBus, #[with(3)] fixture_queues: Box<[Queu
     };
     let dev = param.build("vsock").unwrap();
 
-    assert_matches!(dev.id(), DeviceId::Socket);
+    assert_matches!(dev.id(), DeviceId::SOCKET);
     assert_eq!(dev.name(), "vsock");
     assert_eq!(dev.num_queues(), 3);
     assert_eq!(dev.config().guest_cid, GUEST_CID as u32);

alioth/src/virtio/pci.rs

@@ -576,10 +576,10 @@ const VIRTIO_DEVICE_ID_BASE: u16 = 0x1040;
 
 fn get_class(id: DeviceId) -> (u8, u8) {
     match id {
-        DeviceId::Net => (0x02, 0x00),
-        DeviceId::FileSystem => (0x01, 0x80),
-        DeviceId::Block => (0x01, 0x00),
-        DeviceId::Socket => (0x02, 0x80),
+        DeviceId::NET => (0x02, 0x00),
+        DeviceId::FILE_SYSTEM => (0x01, 0x80),
+        DeviceId::BLOCK => (0x01, 0x00),
+        DeviceId::SOCKET => (0x02, 0x80),
         _ => (0xff, 0x00),
     }
 }
@@ -690,14 +690,14 @@ where
         let mut header = DeviceHeader {
             common: CommonHeader {
                 vendor: VIRTIO_VENDOR_ID,
-                device: VIRTIO_DEVICE_ID_BASE + dev.id as u16,
+                device: VIRTIO_DEVICE_ID_BASE + dev.id.raw(),
                 revision: 0x1,
                 header_type: HeaderType::DEVICE,
                 class,
                 subclass,
                 ..Default::default()
             },
-            subsystem: VIRTIO_DEVICE_ID_BASE + dev.id as u16,
+            subsystem: VIRTIO_DEVICE_ID_BASE + dev.id.raw(),
             ..Default::default()
         };
         let device_config = dev.device_config.clone();

alioth/src/virtio/virtio.rs

@@ -31,8 +31,8 @@ use std::path::Path;
 
 use snafu::Snafu;
 
-use crate::bitflags;
 use crate::errors::{DebugTrace, trace_error};
+use crate::{bitflags, consts};
 
 #[trace_error]
 #[derive(Snafu, DebugTrace)]
@@ -99,17 +99,18 @@ const FEATURE_BUILT_IN: u128 = VirtioFeature::EVENT_IDX.bits()
     | VirtioFeature::RING_PACKED.bits()
     | VirtioFeature::VERSION_1.bits();
 
-#[derive(Debug, Clone, Copy)]
-pub enum DeviceId {
-    Net = 1,
-    Block = 2,
-    Entropy = 4,
-    Balloon = 5,
-    Socket = 19,
-    Iommu = 23,
-    Mem = 24,
-    FileSystem = 26,
-    Pmem = 27,
+consts! {
+    pub struct DeviceId(u16) {
+        NET = 1;
+        BLOCK = 2;
+        ENTROPY = 4;
+        BALLOON = 5;
+        SOCKET = 19;
+        IOMMU = 23;
+        MEM = 24;
+        FILE_SYSTEM = 26;
+        PMEM = 27;
+    }
 }
 
 bitflags! {