Merge "Fix EmitSequenceData bug" into main am: c4b9840456

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2877302

Change-Id: I17a055fd3fbbdbc64c8a4b0f063fc843451bf3ef
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
This commit is contained in:
Treehugger Robot 2023-12-20 23:27:47 +00:00 committed by Automerger Merge Worker
commit af7a667271
2 changed files with 28 additions and 10 deletions

View file

@ -1,10 +1,3 @@
// Copyright (C) 2023 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
@ -15,6 +8,7 @@
#include <sys/stat.h>
#include <cstdio>
#include <limits>
#include <memory>
#include <android-base/file.h>
@ -513,19 +507,24 @@ TEST_F(CowTestV3, BufferMetadataSyncTest) {
TEST_F(CowTestV3, SequenceTest) {
CowOptions options;
options.op_count_max = std::numeric_limits<uint32_t>::max();
constexpr int seq_len = std::numeric_limits<uint16_t>::max() / sizeof(uint32_t) + 1;
options.op_count_max = seq_len;
auto writer = CreateCowWriter(3, options, GetCowFd());
// sequence data. This just an arbitrary set of integers that specify the merge order. The
// actual calculation is done by update_engine and passed to writer. All we care about here is
// writing that data correctly
const int seq_len = std::numeric_limits<uint16_t>::max() / sizeof(uint32_t) + 1;
uint32_t sequence[seq_len];
for (int i = 0; i < seq_len; i++) {
sequence[i] = i + 1;
}
ASSERT_TRUE(writer->AddSequenceData(seq_len, sequence));
ASSERT_TRUE(writer->AddZeroBlocks(1, seq_len));
ASSERT_TRUE(writer->AddZeroBlocks(1, seq_len - 1));
std::vector<uint8_t> data(writer->GetBlockSize());
for (size_t i = 0; i < data.size(); i++) {
data[i] = static_cast<uint8_t>(i & 0xFF);
}
ASSERT_TRUE(writer->AddRawBlocks(seq_len, data.data(), data.size()));
ASSERT_TRUE(writer->Finalize());
ASSERT_EQ(lseek(cow_->fd, 0, SEEK_SET), 0);
@ -539,6 +538,12 @@ TEST_F(CowTestV3, SequenceTest) {
const auto& op = iter->Get();
ASSERT_EQ(op->new_block, seq_len - i);
if (op->new_block == seq_len) {
std::vector<uint8_t> read_back(writer->GetBlockSize());
ASSERT_EQ(reader.ReadData(op, read_back.data(), read_back.size()),
static_cast<ssize_t>(read_back.size()));
ASSERT_EQ(read_back, data);
}
iter->Next();
}

View file

@ -382,7 +382,20 @@ bool CowWriterV3::EmitLabel(uint64_t label) {
bool CowWriterV3::EmitSequenceData(size_t num_ops, const uint32_t* data) {
// TODO: size sequence buffer based on options
if (header_.op_count > 0) {
LOG(ERROR)
<< "There's " << header_.op_count
<< " operations written to disk. Writing sequence data is only allowed before all "
"operation writes.";
return false;
}
header_.sequence_data_count = num_ops;
// In COW format v3, data section is placed after op section and sequence
// data section. Therefore, changing the sequence data count has the effect
// of moving op section and data section. Therefore we need to reset the
// value of |next_data_pos|. This is also the reason why writing sequence
// data is only allowed if there's no operation written.
next_data_pos_ = GetDataOffset(header_);
if (!android::base::WriteFullyAtOffset(fd_, data, sizeof(data[0]) * num_ops,
GetSequenceOffset(header_))) {
PLOG(ERROR) << "writing sequence buffer failed";