commit 28def4f0c85de00c3602c99c9131abab7f9f1874
author Zentaro Kavanagh <zentaro@chromium.org> Tue Jan 15 17:15:01 2019 -0800
committer chrome-bot <chrome-bot@chromium.org> Wed Apr 24 15:51:33 2019 -0700
tree b4c9a5e21c1987d9e86a369c3f01f2eae529a4cf
parent 84634dc7ae13a4e887937bded8f9486a2869e73c

update_engine: Place enterprise rollback save marker file

- There are now two types of rollback. One that does a full powerwash
  and one that save some system state.
- When an enterprise rollback powerwash is scheduled, place a marker
  file to tell the shutdown process to save data before rebooting.
- This lets rollback preserve additional data over a powerwash that
  can be restored later.
- Change a few places that were using is_rollback to save_rollback_data
  to be explicit.

BUG=chromium:955463
TEST=unittests

Change-Id: I9f18319e711e425a6e712dd319e03bcc6ddd0a1b
Reviewed-on: https://chromium-review.googlesource.com/1414030
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>

update_manager/android_things_policy.cc

diff --git a/update_manager/android_things_policy.cc b/update_manager/android_things_policy.cc
index 4afcf12..26bd0ba 100644
--- a/update_manager/android_things_policy.cc
+++ b/update_manager/android_things_policy.cc
@@ -54,6 +54,7 @@
   result->target_channel.clear();
   result->target_version_prefix.clear();
   result->rollback_allowed = false;
+  result->rollback_data_save_requested = false;
   result->rollback_allowed_milestones = -1;
   result->interactive = false;
 

update_manager/enterprise_device_policy_impl.cc

diff --git a/update_manager/enterprise_device_policy_impl.cc b/update_manager/enterprise_device_policy_impl.cc
index a3430ef..3d77d59 100644
--- a/update_manager/enterprise_device_policy_impl.cc
+++ b/update_manager/enterprise_device_policy_impl.cc
@@ -91,22 +91,27 @@
         case RollbackToTargetVersion::kDisabled:
           LOG(INFO) << "Policy disables rollbacks.";
           result->rollback_allowed = false;
+          result->rollback_data_save_requested = false;
           break;
         case RollbackToTargetVersion::kRollbackAndPowerwash:
           LOG(INFO) << "Policy allows rollbacks with powerwash.";
           result->rollback_allowed = true;
+          result->rollback_data_save_requested = false;
           break;
         case RollbackToTargetVersion::kRollbackAndRestoreIfPossible:
           LOG(INFO)
               << "Policy allows rollbacks, also tries to restore if possible.";
-          // We don't support restore yet, but policy still allows rollback.
           result->rollback_allowed = true;
+          result->rollback_data_save_requested = true;
           break;
         case RollbackToTargetVersion::kRollbackOnlyIfRestorePossible:
+          // TODO(crbug.com/947621): Remove this policy option until we know
+          // how it could be supported correctly.
           LOG(INFO) << "Policy only allows rollbacks if restore is possible.";
           // We don't support restore yet, policy doesn't allow rollback in this
           // case.
           result->rollback_allowed = false;
+          result->rollback_data_save_requested = false;
           break;
         case RollbackToTargetVersion::kMaxValue:
           NOTREACHED();

update_manager/policy.h

diff --git a/update_manager/policy.h b/update_manager/policy.h
index 5d65d9a..9e7df10 100644
--- a/update_manager/policy.h
+++ b/update_manager/policy.h
@@ -50,6 +50,8 @@
   std::string target_version_prefix;
   // Specifies whether rollback images are allowed by device policy.
   bool rollback_allowed;
+  // Specifies if rollbacks should attempt to preserve some system state.
+  bool rollback_data_save_requested;
   // Specifies the number of Chrome milestones rollback should be allowed,
   // starting from the stable version at any time. Value is -1 if unspecified
   // (e.g. no device policy is available yet), in this case no version