Only skip operation on snapshot partitions

On Virtual A/B devices, don't skip SOURCE_COPY on
static partitions.

Test: update_engine_unittest
Test: incremental update to self
Change-Id: I5c93b501e09f50f559151eb77d83052373c90d0d
diff --git a/common/dynamic_partition_control_interface.h b/common/dynamic_partition_control_interface.h
index 39daf75..c17bafb 100644
--- a/common/dynamic_partition_control_interface.h
+++ b/common/dynamic_partition_control_interface.h
@@ -50,8 +50,12 @@
   // Return the feature flags of Virtual A/B on this device.
   virtual FeatureFlag GetVirtualAbFeatureFlag() = 0;
 
-  // Checks if the provided InstallOperation can be skipped on this device.
-  virtual bool ShouldSkipOperation(const InstallOperation& operation) = 0;
+  // Checks if |operation| can be skipped on the given partition.
+  // |partition_name| should not have the slot suffix; implementation of
+  // DynamicPartitionControlInterface checks partition at the target slot
+  // previously set with PreparePartitionsForUpdate().
+  virtual bool ShouldSkipOperation(const std::string& partition_name,
+                                   const InstallOperation& operation) = 0;
 
   // Do necessary cleanups before destroying the object.
   virtual void Cleanup() = 0;
diff --git a/common/dynamic_partition_control_stub.cc b/common/dynamic_partition_control_stub.cc
index 06f6b3c..bc792c8 100644
--- a/common/dynamic_partition_control_stub.cc
+++ b/common/dynamic_partition_control_stub.cc
@@ -33,7 +33,7 @@
 }
 
 bool DynamicPartitionControlStub::ShouldSkipOperation(
-    const InstallOperation& operation) {
+    const std::string& partition_name, const InstallOperation& operation) {
   return false;
 }
 
diff --git a/common/dynamic_partition_control_stub.h b/common/dynamic_partition_control_stub.h
index c62758b..1704f05 100644
--- a/common/dynamic_partition_control_stub.h
+++ b/common/dynamic_partition_control_stub.h
@@ -29,7 +29,8 @@
  public:
   FeatureFlag GetDynamicPartitionsFeatureFlag() override;
   FeatureFlag GetVirtualAbFeatureFlag() override;
-  bool ShouldSkipOperation(const InstallOperation& operation) override;
+  bool ShouldSkipOperation(const std::string& partition_name,
+                           const InstallOperation& operation) override;
   void Cleanup() override;
   bool PreparePartitionsForUpdate(uint32_t source_slot,
                                   uint32_t target_slot,
diff --git a/dynamic_partition_control_android.cc b/dynamic_partition_control_android.cc
index 4414e4b..4ad02c7 100644
--- a/dynamic_partition_control_android.cc
+++ b/dynamic_partition_control_android.cc
@@ -106,11 +106,13 @@
 }
 
 bool DynamicPartitionControlAndroid::ShouldSkipOperation(
-    const InstallOperation& operation) {
+    const std::string& partition_name, const InstallOperation& operation) {
   switch (operation.type()) {
     case InstallOperation::SOURCE_COPY:
       return target_supports_snapshot_ &&
              GetVirtualAbFeatureFlag().IsEnabled() &&
+             mapped_devices_.count(partition_name +
+                                   SlotSuffixForSlotNumber(target_slot_)) > 0 &&
              SourceCopyOperationIsClone(operation);
       break;
     default:
@@ -371,6 +373,9 @@
     uint32_t target_slot,
     const DeltaArchiveManifest& manifest,
     bool update) {
+  source_slot_ = source_slot;
+  target_slot_ = target_slot;
+
   if (fs_mgr_overlayfs_is_setup()) {
     // Non DAP devices can use overlayfs as well.
     LOG(WARNING)
@@ -675,4 +680,9 @@
   return DynamicPartitionDeviceStatus::ERROR;
 }
 
+void DynamicPartitionControlAndroid::set_fake_mapped_devices(
+    const std::set<std::string>& fake) {
+  mapped_devices_ = fake;
+}
+
 }  // namespace chromeos_update_engine
diff --git a/dynamic_partition_control_android.h b/dynamic_partition_control_android.h
index 2bfbcb1..13fbb1a 100644
--- a/dynamic_partition_control_android.h
+++ b/dynamic_partition_control_android.h
@@ -35,7 +35,8 @@
   ~DynamicPartitionControlAndroid();
   FeatureFlag GetDynamicPartitionsFeatureFlag() override;
   FeatureFlag GetVirtualAbFeatureFlag() override;
-  bool ShouldSkipOperation(const InstallOperation& operation) override;
+  bool ShouldSkipOperation(const std::string& partition_name,
+                           const InstallOperation& operation) override;
   void Cleanup() override;
 
   bool PreparePartitionsForUpdate(uint32_t source_slot,
@@ -122,6 +123,8 @@
   // metadata) for a given slot.
   virtual std::string GetSuperPartitionName(uint32_t slot);
 
+  virtual void set_fake_mapped_devices(const std::set<std::string>& fake);
+
  private:
   friend class DynamicPartitionControlAndroidTest;
 
@@ -182,6 +185,8 @@
   // Whether the target partitions should be loaded as dynamic partitions. Set
   // by PreparePartitionsForUpdate() per each update.
   bool is_target_dynamic_ = false;
+  uint32_t source_slot_ = UINT32_MAX;
+  uint32_t target_slot_ = UINT32_MAX;
 
   DISALLOW_COPY_AND_ASSIGN(DynamicPartitionControlAndroid);
 };
diff --git a/dynamic_partition_control_android_unittest.cc b/dynamic_partition_control_android_unittest.cc
index fc3d38c..207a97e 100644
--- a/dynamic_partition_control_android_unittest.cc
+++ b/dynamic_partition_control_android_unittest.cc
@@ -620,18 +620,22 @@
       << "Should not be able to apply to current slot.";
 }
 
-TEST_F(DynamicPartitionControlAndroidTest, ShouldSkipOperationTest) {
+TEST_P(DynamicPartitionControlAndroidTestP, ShouldSkipOperationTest) {
+  ASSERT_TRUE(dynamicControl().PreparePartitionsForUpdate(
+      source(), target(), PartitionSizesToManifest({{"foo", 4_MiB}}), false));
+  dynamicControl().set_fake_mapped_devices({T("foo")});
+
   InstallOperation iop;
   Extent *se, *de;
 
   // Not a SOURCE_COPY operation, cannot skip.
   iop.set_type(InstallOperation::REPLACE);
-  EXPECT_FALSE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   iop.set_type(InstallOperation::SOURCE_COPY);
 
   // By default GetVirtualAbFeatureFlag is disabled. Cannot skip operation.
-  EXPECT_FALSE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   // Enable GetVirtualAbFeatureFlag in the mock interface.
   ON_CALL(dynamicControl(), GetVirtualAbFeatureFlag())
@@ -639,19 +643,19 @@
 
   // By default target_supports_snapshot_ is set to false. Cannot skip
   // operation.
-  EXPECT_FALSE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   SetSnapshotEnabled(true);
 
   // Empty source and destination. Skip.
-  EXPECT_TRUE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_TRUE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   se = iop.add_src_extents();
   se->set_start_block(0);
   se->set_num_blocks(1);
 
   // There is something in sources, but destinations are empty. Cannot skip.
-  EXPECT_FALSE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   InstallOperation iop2;
 
@@ -660,42 +664,45 @@
   de->set_num_blocks(1);
 
   // There is something in destinations, but sources are empty. Cannot skip.
-  EXPECT_FALSE(dynamicControl().ShouldSkipOperation(iop2));
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("foo", iop2));
 
   de = iop.add_dst_extents();
   de->set_start_block(0);
   de->set_num_blocks(1);
 
   // Sources and destinations are identical. Skip.
-  EXPECT_TRUE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_TRUE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   se = iop.add_src_extents();
   se->set_start_block(1);
   se->set_num_blocks(5);
 
   // There is something in source, but not in destination. Cannot skip.
-  EXPECT_FALSE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   de = iop.add_dst_extents();
   de->set_start_block(1);
   de->set_num_blocks(5);
 
   // There is source and destination are equal. Skip.
-  EXPECT_TRUE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_TRUE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   de = iop.add_dst_extents();
   de->set_start_block(6);
   de->set_num_blocks(5);
 
   // There is something extra in dest. Cannot skip.
-  EXPECT_FALSE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("foo", iop));
 
   se = iop.add_src_extents();
   se->set_start_block(6);
   se->set_num_blocks(5);
 
   // Source and dest are identical again. Skip.
-  EXPECT_TRUE(dynamicControl().ShouldSkipOperation(iop));
+  EXPECT_TRUE(dynamicControl().ShouldSkipOperation("foo", iop));
+
+  // Don't skip for static partitions.
+  EXPECT_FALSE(dynamicControl().ShouldSkipOperation("bar", iop));
 }
 
 }  // namespace chromeos_update_engine
diff --git a/mock_dynamic_partition_control.h b/mock_dynamic_partition_control.h
index db8e834..09b825d 100644
--- a/mock_dynamic_partition_control.h
+++ b/mock_dynamic_partition_control.h
@@ -17,6 +17,7 @@
 #include <stdint.h>
 
 #include <memory>
+#include <set>
 #include <string>
 
 #include <gmock/gmock.h>
@@ -69,6 +70,10 @@
   MOCK_METHOD1(GetSuperPartitionName, std::string(uint32_t));
   MOCK_METHOD0(GetVirtualAbFeatureFlag, FeatureFlag());
   MOCK_METHOD0(FinishUpdate, bool());
+
+  void set_fake_mapped_devices(const std::set<std::string>& fake) override {
+    DynamicPartitionControlAndroid::set_fake_mapped_devices(fake);
+  }
 };
 
 }  // namespace chromeos_update_engine
diff --git a/payload_consumer/delta_performer.cc b/payload_consumer/delta_performer.cc
index 3d38c5b..c49474c 100644
--- a/payload_consumer/delta_performer.cc
+++ b/payload_consumer/delta_performer.cc
@@ -1157,8 +1157,10 @@
   // The device may optimize the SOURCE_COPY operation.
   // Being this a device-specific optimization let DynamicPartitionController
   // decide it the operation should be skipped.
+  const PartitionUpdate& partition = partitions_[current_partition_];
   const auto& partition_control = boot_control_->GetDynamicPartitionControl();
-  bool should_skip = partition_control->ShouldSkipOperation(operation);
+  bool should_skip = partition_control->ShouldSkipOperation(
+      partition.partition_name(), operation);
 
   if (operation.has_src_sha256_hash()) {
     bool read_ok;