crosvm: add ability to enable caps on vcpu

This change primarily adds functionality to allow kvm features to be
enabled on a vcpu (most of the current infra only supporst the ioctl for
the vm fd).

BUG=b:144746965
TEST=ran 'build_test' and verified that the added tests passed.

Change-Id: I30c00b6f462377c21d477602ceba5853df953b37
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/2055883
Tested-by: Matt Delco <delco@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Dmitry Torokhov <dtor@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
Commit-Queue: Matt Delco <delco@chromium.org>

2 files changed, 70 insertions, 0 deletions

diff --git a/tests/plugin_enable_cap.c b/tests/plugin_enable_cap.c
new file mode 100644
index 0000000..60977ef
--- /dev/null
+++ b/tests/plugin_enable_cap.c
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <errno.h>
+#include <linux/kvm.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "crosvm.h"
+
+int main(int argc, char** argv) {
+    struct crosvm* crosvm = NULL;
+    uint64_t cap_args[4] = {0};
+
+    int ret = crosvm_connect(&crosvm);
+    if (ret) {
+        fprintf(stderr, "failed to connect to crosvm: %d\n", ret);
+        return 1;
+    }
+
+    struct crosvm_vcpu* vcpu = NULL;
+    ret = crosvm_get_vcpu(crosvm, 0, &vcpu);
+    if (ret) {
+        fprintf(stderr, "failed to get vcpu #0: %d\n", ret);
+        return 1;
+    }
+
+    ret = crosvm_start(crosvm);
+    if (ret) {
+        fprintf(stderr, "failed to start vm: %d\n", ret);
+        return 1;
+    }
+
+    struct crosvm_vcpu_event evt = {0};
+    ret = crosvm_vcpu_wait(vcpu, &evt);
+    if (ret) {
+        fprintf(stderr, "failed to wait for vm start: %d\n", ret);
+        return 1;
+    }
+    if (evt.kind != CROSVM_VCPU_EVENT_KIND_INIT) {
+        fprintf(stderr, "Got unexpected exit type: %d\n", evt.kind);
+        return 1;
+    }
+
+    ret = crosvm_enable_capability(crosvm, 0, 0, cap_args);
+    if (ret != -EINVAL) {
+        fprintf(stderr, "Unexpected crosvm_enable_capability result: %d\n",
+                ret);
+        return 1;
+    }
+
+    ret = crosvm_vcpu_enable_capability(vcpu, KVM_CAP_HYPERV_SYNIC, 0,
+                                        cap_args);
+    if (ret) {
+        fprintf(stderr, "crosvm_vcpu_enable_capability() failed: %d\n", ret);
+        return 1;
+    }
+
+    return 0;
+}
diff --git a/tests/plugins.rs b/tests/plugins.rs
index d56f4ce..c45096f 100644
--- a/tests/plugins.rs
+++ b/tests/plugins.rs
@@ -261,6 +261,11 @@ fn test_supported_cpuid() {
 }
 
 #[test]
+fn test_enable_cap() {
+    test_plugin(include_str!("plugin_enable_cap.c"));
+}
+
+#[test]
 fn test_msr_index_list() {
     test_plugin(include_str!("plugin_msr_index_list.c"));
 }