Fix build on x86

virtio-core/src/arch/x86.rs

@@ -1,3 +1,14 @@
+use crate::{
+    legacy_transport::LegacyTransport,
+    reinit,
+    transport::Error,
+    utils::VolatileCell,
+    Device,
+};
+use std::fs::File;
+
+use pcid_interface::*;
+
 pub fn enable_msix(pcid_handle: &mut PcidServerHandle) -> Result<File, Error> {
     panic!("virtio-core: x86 doesn't support enable_msix")
 }
@@ -6,5 +17,36 @@ pub fn probe_legacy_port_transport<'a>(
     pci_header: &PciHeader,
     pcid_handle: &mut PcidServerHandle,
 ) -> Result<Device<'a>, Error> {
-    crate::x86_64::probe_legacy_port_transport(pci_header, pcid_handle)
-}
+    if let PciBar::Port(port) = pci_header.get_bar(0) {
+        unsafe { syscall::iopl(3).expect("virtio: failed to set I/O privilege level") };
+        log::warn!("virtio: using legacy transport");
+
+        static SHIM: VolatileCell<u32> = VolatileCell::new(0);
+
+        let transport = LegacyTransport::new(port);
+
+        // Setup interrupts.
+        let all_pci_features = pcid_handle.fetch_all_features()?;
+        let has_msix = all_pci_features
+            .iter()
+            .any(|(feature, _)| feature.is_msix());
+
+        // According to the virtio specification, the device REQUIRED to support MSI-X.
+        assert!(has_msix, "virtio: device does not support MSI-X");
+        let irq_handle = enable_msix(pcid_handle)?;
+
+        let device = Device {
+            transport,
+            irq_handle,
+            isr: &SHIM,
+            device_space: core::ptr::null_mut(),
+        };
+
+        device.transport.reset();
+        reinit(&device)?;
+
+        Ok(device)
+    } else {
+        unreachable!("virtio: legacy transport with non-port IO?")
+    }
+}