Properly set target build vars for partial updates.
If partial_update flag is set in payload, additionally do the following:
- Set is_target_dynamic to true; that is, assume that the target build
supports dynamic partitions
- Assert that current and target build supports Virtual A/B.
For non-partial updates, there is no change in behavior.
Bug: 162616968
Test: apply GKI update
Change-Id: I773b609c7a3f942827fd8b8f0f80f602884efb12
diff --git a/dynamic_partition_control_android.cc b/dynamic_partition_control_android.cc
index ba749d9..aa0f393 100644
--- a/dynamic_partition_control_android.cc
+++ b/dynamic_partition_control_android.cc
@@ -434,17 +434,17 @@
return false;
}
+ if (!SetTargetBuildVars(manifest)) {
+ return false;
+ }
+
// Although the current build supports dynamic partitions, the given payload
// doesn't use it for target partitions. This could happen when applying a
// retrofit update. Skip updating the partition metadata for the target slot.
- is_target_dynamic_ = !manifest.dynamic_partition_metadata().groups().empty();
if (!is_target_dynamic_) {
return true;
}
- target_supports_snapshot_ =
- manifest.dynamic_partition_metadata().snapshot_enabled();
-
if (!update)
return true;
@@ -505,6 +505,52 @@
return true;
}
+bool DynamicPartitionControlAndroid::SetTargetBuildVars(
+ const DeltaArchiveManifest& manifest) {
+ // Precondition: current build supports dynamic partition.
+ CHECK(GetDynamicPartitionsFeatureFlag().IsEnabled());
+
+ bool is_target_dynamic =
+ !manifest.dynamic_partition_metadata().groups().empty();
+ bool target_supports_snapshot =
+ manifest.dynamic_partition_metadata().snapshot_enabled();
+
+ if (manifest.partial_update()) {
+ // Partial updates requires DAP. On partial updates that does not involve
+ // dynamic partitions, groups() can be empty, so also assume
+ // is_target_dynamic in this case. This assumption should be safe because we
+ // also check target_supports_snapshot below, which presumably also implies
+ // target build supports dynamic partition.
+ if (!is_target_dynamic) {
+ LOG(INFO) << "Assuming target build supports dynamic partitions for "
+ "partial updates.";
+ is_target_dynamic = true;
+ }
+
+ // Partial updates requires Virtual A/B. Double check that both current
+ // build and target build supports Virtual A/B.
+ if (!GetVirtualAbFeatureFlag().IsEnabled()) {
+ LOG(ERROR) << "Partial update cannot be applied on a device that does "
+ "not support snapshots.";
+ return false;
+ }
+ if (!target_supports_snapshot) {
+ LOG(ERROR) << "Cannot apply partial update to a build that does not "
+ "support snapshots.";
+ return false;
+ }
+ }
+
+ // Store the flags.
+ is_target_dynamic_ = is_target_dynamic;
+ // If !is_target_dynamic_, leave target_supports_snapshot_ unset because
+ // snapshots would not work without dynamic partition.
+ if (is_target_dynamic_) {
+ target_supports_snapshot_ = target_supports_snapshot;
+ }
+ return true;
+}
+
namespace {
// Try our best to erase AVB footer.
class AvbFooterEraser {
diff --git a/dynamic_partition_control_android.h b/dynamic_partition_control_android.h
index 08656fd..9ee85db 100644
--- a/dynamic_partition_control_android.h
+++ b/dynamic_partition_control_android.h
@@ -267,6 +267,10 @@
// doing anything.
bool EnsureMetadataMounted();
+ // Set boolean flags related to target build. This includes flags like
+ // target_supports_snapshot_ and is_target_dynamic_.
+ bool SetTargetBuildVars(const DeltaArchiveManifest& manifest);
+
std::set<std::string> mapped_devices_;
const FeatureFlag dynamic_partitions_;
const FeatureFlag virtual_ab_;
