vfio_device: add MSHV support

Signed-off-by: Wei Liu <liuwe@microsoft.com>

src/vfio_device.rs

@@ -22,6 +22,12 @@ use kvm_bindings::{
 #[cfg(feature = "kvm")]
 use kvm_ioctls::DeviceFd;
 use log::{debug, error, warn};
+#[cfg(feature = "mshv")]
+use mshv_bindings::{
+    mshv_device_attr, MSHV_DEV_VFIO_GROUP, MSHV_DEV_VFIO_GROUP_ADD, MSHV_DEV_VFIO_GROUP_DEL,
+};
+#[cfg(feature = "mshv")]
+use mshv_ioctls::DeviceFd;
 use vfio_bindings::bindings::vfio::*;
 use vm_memory::{Address, GuestMemory, GuestMemoryRegion, MemoryRegionAddress};
 use vmm_sys_util::errno::Error as SysError;
@@ -48,6 +54,8 @@ pub enum VfioError {
     GroupGetDeviceFD,
     #[cfg(feature = "kvm")]
     KvmSetDeviceAttr(SysError),
+    #[cfg(feature = "mshv")]
+    MshvSetDeviceAttr(SysError),
     VfioDeviceGetInfo,
     VfioDeviceGetRegionInfo(SysError),
     InvalidPath,
@@ -91,6 +99,10 @@ impl fmt::Display for VfioError {
             VfioError::KvmSetDeviceAttr(e) => {
                 write!(f, "failed to set KVM vfio device's attribute: {}", e)
             }
+            #[cfg(feature = "mshv")]
+            VfioError::MshvSetDeviceAttr(e) => {
+                write!(f, "failed to set MSHV vfio device's attribute: {}", e)
+            }
             VfioError::VfioDeviceGetInfo => {
                 write!(f, "failed to get vfio device's info or info doesn't match")
             }
@@ -125,6 +137,8 @@ impl std::error::Error for VfioError {
             VfioError::GroupGetDeviceFD => None,
             #[cfg(feature = "kvm")]
             VfioError::KvmSetDeviceAttr(e) => Some(e),
+            #[cfg(feature = "mshv")]
+            VfioError::MshvSetDeviceAttr(e) => Some(e),
             VfioError::VfioDeviceGetInfo => None,
             VfioError::VfioDeviceGetRegionInfo(e) => Some(e),
             VfioError::InvalidPath => None,
@@ -259,6 +273,36 @@ impl VfioContainer {
             .map_err(VfioError::KvmSetDeviceAttr)
     }
 
+    #[cfg(feature = "mshv")]
+    fn mshv_device_add_group(&self, group_fd: RawFd) -> Result<()> {
+        let group_fd_ptr = &group_fd as *const i32;
+        let dev_attr = mshv_device_attr {
+            flags: 0,
+            group: MSHV_DEV_VFIO_GROUP,
+            attr: u64::from(MSHV_DEV_VFIO_GROUP_ADD),
+            addr: group_fd_ptr as u64,
+        };
+
+        self.device_fd
+            .set_device_attr(&dev_attr)
+            .map_err(VfioError::MshvSetDeviceAttr)
+    }
+
+    #[cfg(feature = "mshv")]
+    fn mshv_device_del_group(&self, group_fd: RawFd) -> Result<()> {
+        let group_fd_ptr = &group_fd as *const i32;
+        let dev_attr = mshv_device_attr {
+            flags: 0,
+            group: MSHV_DEV_VFIO_GROUP,
+            attr: u64::from(MSHV_DEV_VFIO_GROUP_DEL),
+            addr: group_fd_ptr as u64,
+        };
+
+        self.device_fd
+            .set_device_attr(&dev_attr)
+            .map_err(VfioError::MshvSetDeviceAttr)
+    }
+
     fn get_group(&self, group_id: u32) -> Result<Arc<VfioGroup>> {
         // Safe because there's no legal way to break the lock.
         let mut hash = self.groups.lock().unwrap();
@@ -289,7 +333,11 @@ impl VfioContainer {
 
         // Add the new group object to the KVM driver.
         #[cfg(feature = "kvm")]
-        if let Err(e) = self.kvm_device_add_group(group.as_raw_fd()) {
+        let result = self.kvm_device_add_group(group.as_raw_fd());
+        #[cfg(feature = "mshv")]
+        let result = self.mshv_device_add_group(group.as_raw_fd());
+
+        if let Err(e) = result {
             let _ =
                 unsafe { ioctl_with_ref(&*group, VFIO_GROUP_UNSET_CONTAINER(), &self.as_raw_fd()) };
             return Err(e);
@@ -311,7 +359,11 @@ impl VfioContainer {
         // - one reference held by the groups hashmap
         if Arc::strong_count(&group) == 3 {
             #[cfg(feature = "kvm")]
-            match self.kvm_device_del_group(group.as_raw_fd()) {
+            let result = self.kvm_device_del_group(group.as_raw_fd());
+            #[cfg(feature = "mshv")]
+            let result = self.mshv_device_del_group(group.as_raw_fd());
+
+            match result {
                 Ok(_) => {}
                 Err(e) => {
                     error!("Could not delete VFIO group: {:?}", e);