arcvm: Support demo mode

When it is enabled, the CL mounts the squashfs image as /dev/vdd.

BUG=b:143780893
TEST=manually place the image file in /run/imageloader as Omaha side
 is not ready yet, manually modify the UpgradeParams, then start ARCVM
 and run 'mount /dev/block/vdd /odm' in android-sh.

Change-Id: I7744ad8d3d2d79b5a2efa21384fa8ea256c0df23
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2016290
Commit-Queue: Yusuke Sato <yusukes@chromium.org>
Auto-Submit: Yusuke Sato <yusukes@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735000}

components/arc/session/arc_vm_client_adapter.cc

@@ -155,7 +155,6 @@ std::vector<std::string> GenerateKernelCmdline(
     }
   }
 
-  // TODO(yusukes): Handle |demo_session_apps_path| in |upgrade_params|.
   // TODO(yusukes): Handle |is_managed_account| in |upgrade_params|.
   return result;
 }
@@ -164,6 +163,7 @@ vm_tools::concierge::StartArcVmRequest CreateStartArcVmRequest(
     const std::string& user_id_hash,
     uint32_t cpus,
     const base::FilePath& data_disk_path,
+    const base::FilePath& demo_session_apps_path,
     const FileSystemStatus& file_system_status,
     std::vector<std::string> kernel_cmdline) {
   vm_tools::concierge::StartArcVmRequest request;
@@ -207,10 +207,18 @@ vm_tools::concierge::StartArcVmRequest CreateStartArcVmRequest(
   // Add /vendor as /dev/vdc.
   disk_image = request.add_disks();
   disk_image->set_path(file_system_status.vendor_image_path().value());
-
   disk_image->set_image_type(vm_tools::concierge::DISK_IMAGE_AUTO);
   disk_image->set_writable(false);
   disk_image->set_do_mount(true);
+  // Add /run/imageloader/.../android_demo_apps.squash as /dev/vdd if needed.
+  // TODO(b/144542975): Do this on upgrade instead.
+  if (!demo_session_apps_path.empty()) {
+    disk_image = request.add_disks();
+    disk_image->set_path(demo_session_apps_path.value());
+    disk_image->set_image_type(vm_tools::concierge::DISK_IMAGE_AUTO);
+    disk_image->set_writable(false);
+    disk_image->set_do_mount(true);
+  }
 
   // Add Android fstab.
   request.set_fstab(file_system_status.fstab_path().value());
@@ -494,9 +502,9 @@ class ArcVmClientAdapter : public ArcClientAdapter,
         start_params_, params, file_system_status, *is_dev_mode_,
         is_host_on_vm_, version_info::GetChannelString(channel_),
         serial_number_);
-    auto start_request =
-        CreateStartArcVmRequest(user_id_hash_, cpus, data_disk_path,
-                                file_system_status, std::move(kernel_cmdline));
+    auto start_request = CreateStartArcVmRequest(
+        user_id_hash_, cpus, data_disk_path, params.demo_session_apps_path,
+        file_system_status, std::move(kernel_cmdline));
 
     GetConciergeClient()->StartArcVm(
         start_request,

components/arc/session/arc_vm_client_adapter_unittest.cc

@@ -592,6 +592,38 @@ TEST_F(ArcVmClientAdapterTest, StartUpgradeArc_VariousParams2) {
   EXPECT_FALSE(arc_instance_stopped_called());
 }
 
+// Try to start and upgrade the instance with demo mode enabled.
+TEST_F(ArcVmClientAdapterTest, StartUpgradeArc_DemoMode) {
+  constexpr char kDemoImage[] =
+      "/run/imageloader/demo-mode-resources/0.0.1.7/android_demo_apps.squash";
+
+  StartParams start_params(GetPopulatedStartParams());
+  SetValidUserInfo();
+  StartMiniArcWithParams(std::move(start_params));
+
+  UpgradeParams params(GetPopulatedUpgradeParams());
+  // Enable demo mode.
+  params.is_demo_session = true;
+  params.demo_session_apps_path = base::FilePath(kDemoImage);
+
+  UpgradeArcWithParams(true, std::move(params));
+  EXPECT_TRUE(GetStartConciergeCalled());
+  EXPECT_TRUE(GetTestConciergeClient()->start_arc_vm_called());
+  EXPECT_FALSE(arc_instance_stopped_called());
+
+  // Verify the request.
+  auto request = GetTestConciergeClient()->start_arc_vm_request();
+  // Make sure disks have the squashfs image.
+  EXPECT_TRUE(([&kDemoImage, &request]() {
+    for (const auto& disk : request.disks()) {
+      if (disk.path() == kDemoImage)
+        return true;
+    }
+    return false;
+  }()));
+  EXPECT_TRUE(base::Contains(request.params(), "androidboot.arc_demo_mode=1"));
+}
+
 // Tests that StartArcVm() is called with valid parameters.
 TEST_F(ArcVmClientAdapterTest, UpgradeArc_StartArcVmParams) {
   SetValidUserInfo();