libsnapshot: Check cluster size on appends
When appending, if the cluster should end after the given label, ensure
that it does.
Bug: 183985866
Test: cow_api_test#ResumeEndCluster
Change-Id: Ie93d09b3431755d0b9b92761619d55df7f9f6151
diff --git a/fs_mgr/libsnapshot/cow_api_test.cpp b/fs_mgr/libsnapshot/cow_api_test.cpp
index d06427e..b75b154 100644
--- a/fs_mgr/libsnapshot/cow_api_test.cpp
+++ b/fs_mgr/libsnapshot/cow_api_test.cpp
@@ -869,6 +869,67 @@
ASSERT_EQ(num_clusters, 2);
}
+TEST_F(CowTest, ResumeEndCluster) {
+ CowOptions options;
+ int cluster_ops = 5;
+ options.cluster_ops = cluster_ops;
+ auto writer = std::make_unique<CowWriter>(options);
+ ASSERT_TRUE(writer->Initialize(cow_->fd));
+
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 1, "Block 1"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 2, "Block 2"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 3, "Block 3"));
+ ASSERT_TRUE(writer->AddLabel(1));
+ ASSERT_TRUE(writer->Finalize());
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 4, "Block 4"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 5, "Block 5"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 6, "Block 6"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 7, "Block 7"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 8, "Block 8"));
+ ASSERT_EQ(lseek(cow_->fd, 0, SEEK_SET), 0);
+
+ writer = std::make_unique<CowWriter>(options);
+ ASSERT_TRUE(writer->InitializeAppend(cow_->fd, 1));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 4, "Block 4"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 5, "Block 5"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 6, "Block 6"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 7, "Block 7"));
+ ASSERT_TRUE(WriteDataBlock(writer.get(), 8, "Block 8"));
+ ASSERT_TRUE(writer->AddLabel(2));
+ ASSERT_TRUE(writer->Finalize());
+ ASSERT_EQ(lseek(cow_->fd, 0, SEEK_SET), 0);
+
+ CowReader reader;
+ ASSERT_TRUE(reader.Parse(cow_->fd));
+
+ auto iter = reader.GetOpIter();
+ size_t num_replace = 0;
+ size_t max_in_cluster = 0;
+ size_t num_in_cluster = 0;
+ size_t num_clusters = 0;
+ while (!iter->Done()) {
+ const auto& op = iter->Get();
+
+ num_in_cluster++;
+ max_in_cluster = std::max(max_in_cluster, num_in_cluster);
+
+ if (op.type == kCowReplaceOp) {
+ num_replace++;
+
+ ASSERT_EQ(op.new_block, num_replace);
+ ASSERT_TRUE(CompareDataBlock(&reader, op, "Block " + std::to_string(num_replace)));
+ } else if (op.type == kCowClusterOp) {
+ num_in_cluster = 0;
+ num_clusters++;
+ }
+
+ iter->Next();
+ }
+ ASSERT_EQ(num_replace, 8);
+ ASSERT_EQ(max_in_cluster, cluster_ops);
+ ASSERT_EQ(num_clusters, 3);
+}
+
TEST_F(CowTest, DeleteMidCluster) {
CowOptions options;
options.cluster_ops = 7;
diff --git a/fs_mgr/libsnapshot/cow_writer.cpp b/fs_mgr/libsnapshot/cow_writer.cpp
index 8fd1cc4..645ae9d 100644
--- a/fs_mgr/libsnapshot/cow_writer.cpp
+++ b/fs_mgr/libsnapshot/cow_writer.cpp
@@ -236,7 +236,7 @@
PLOG(ERROR) << "lseek failed";
return false;
}
- return true;
+ return EmitClusterIfNeeded();
}
bool CowWriter::EmitCopy(uint64_t new_block, uint64_t old_block) {
@@ -315,6 +315,14 @@
return WriteOperation(op);
}
+bool CowWriter::EmitClusterIfNeeded() {
+ // If there isn't room for another op and the cluster end op, end the current cluster
+ if (cluster_size_ && cluster_size_ < current_cluster_size_ + 2 * sizeof(CowOperation)) {
+ if (!EmitCluster()) return false;
+ }
+ return true;
+}
+
std::basic_string<uint8_t> CowWriter::Compress(const void* data, size_t length) {
switch (compression_) {
case kCowCompressGz: {
@@ -467,12 +475,7 @@
if (!WriteRawData(data, size)) return false;
}
AddOperation(op);
- // If there isn't room for another op and the cluster end op, end the current cluster
- if (cluster_size_ && op.type != kCowClusterOp &&
- cluster_size_ < current_cluster_size_ + 2 * sizeof(op)) {
- if (!EmitCluster()) return false;
- }
- return true;
+ return EmitClusterIfNeeded();
}
void CowWriter::AddOperation(const CowOperation& op) {
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
index 6ffd5d8..a9efad8 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
@@ -115,6 +115,7 @@
private:
bool EmitCluster();
+ bool EmitClusterIfNeeded();
void SetupHeaders();
bool ParseOptions();
bool OpenForWrite();