Add method to query KVM_CAP_X86_DISABLE_EXITS

Add method to query KVM_CAP_X86_DISABLE_EXITS for x86 platforms.

Signed-off-by: Liu Jiang <[email protected]>

Author: jiangliu

src/cap.rs

@@ -140,6 +140,8 @@ pub enum Cap {
     S390UserSigp = KVM_CAP_S390_USER_SIGP,
     #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
     SplitIrqchip = KVM_CAP_SPLIT_IRQCHIP,
+    #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
+    DisableExits = KVM_CAP_X86_DISABLE_EXITS,
     ImmediateExit = KVM_CAP_IMMEDIATE_EXIT,
     ArmVmIPASize = KVM_CAP_ARM_VM_IPA_SIZE,
     MsiDevid = KVM_CAP_MSI_DEVID,

src/ioctls/system.rs

@@ -248,6 +248,26 @@ impl Kvm {
         }
     }
 
+    /// Gets the `KVM_CAP_X86_DISABLE_EXITS` capability.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// # use kvm_ioctls::Kvm;
+    /// let kvm = Kvm::new().unwrap();
+    /// assert!(kvm.get_disable_exits_cap() >= 0);
+    /// ```
+    ///
+    #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
+    pub fn get_disable_exits_cap(&self) -> usize {
+        let x = self.check_extension_int(Cap::DisableExits);
+        if x > 0 {
+            x as usize
+        } else {
+            0
+        }
+    }
+
     #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
     fn get_cpuid(&self, kind: u64, num_entries: usize) -> Result<CpuId> {
         if num_entries > KVM_MAX_CPUID_ENTRIES {
@@ -615,6 +635,13 @@ mod tests {
         assert!(kvm.get_nr_memslots() >= 32);
     }
 
+    #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
+    #[test]
+    fn test_kvm_get_disable_exits() {
+        let kvm = Kvm::new().unwrap();
+        let _disable_exits = kvm.get_disable_exits_cap();
+    }
+
     #[test]
     fn test_create_vm() {
         let kvm = Kvm::new().unwrap();