[PATCH v4 24/28] KVM: TDX: Use guard() to acquire kvm->lock in tdx_vm_ioctl()

[Sean Christopherson]

Use guard() in tdx_vm_ioctl() to tidy up the code a small amount, but more
importantly to minimize the diff of a future change, which will use
guard-like semantics to acquire and release multiple locks.

No functional change intended.

Reviewed-by: Rick Edgecombe <rick.p.edgecombe at intel.com>
Reviewed-by: Kai Huang <kai.huang at intel.com>
Signed-off-by: Sean Christopherson <seanjc at google.com>
---
 arch/x86/kvm/vmx/tdx.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index d6f40a481487..037429964fd7 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -2806,7 +2806,7 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
 	if (r)
 		return r;
 
-	mutex_lock(&kvm->lock);
+	guard(mutex)(&kvm->lock);
 
 	switch (tdx_cmd.id) {
 	case KVM_TDX_CAPABILITIES:
@@ -2819,15 +2819,12 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
 		r = tdx_td_finalize(kvm, &tdx_cmd);
 		break;
 	default:
-		r = -EINVAL;
-		goto out;
+		return -EINVAL;
 	}
 
 	if (copy_to_user(argp, &tdx_cmd, sizeof(struct kvm_tdx_cmd)))
-		r = -EFAULT;
+		return -EFAULT;
 
-out:
-	mutex_unlock(&kvm->lock);
 	return r;
 }
 
-- 
2.51.1.930.gacf6e81ea2-goog