99 lines
3.6 KiB
C++
99 lines
3.6 KiB
C++
//
|
|
// Copyright (C) 2020 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,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
//
|
|
|
|
#include "update_engine/common/cow_operation_convert.h"
|
|
|
|
#include <base/logging.h>
|
|
|
|
#include "update_engine/payload_generator/extent_ranges.h"
|
|
#include "update_engine/payload_generator/extent_utils.h"
|
|
#include "update_engine/update_metadata.pb.h"
|
|
|
|
namespace chromeos_update_engine {
|
|
|
|
namespace {
|
|
|
|
bool IsConsecutive(const CowOperation& op1, const CowOperation& op2) {
|
|
return op1.op == op2.op && op1.dst_block + op1.block_count == op2.dst_block &&
|
|
op1.src_block + op1.block_count == op2.src_block;
|
|
}
|
|
|
|
void push_back(std::vector<CowOperation>* converted, const CowOperation& op) {
|
|
if (!converted->empty() && IsConsecutive(converted->back(), op)) {
|
|
converted->back().block_count++;
|
|
} else {
|
|
converted->push_back(op);
|
|
}
|
|
}
|
|
|
|
} // namespace
|
|
|
|
std::vector<CowOperation> ConvertToCowOperations(
|
|
const ::google::protobuf::RepeatedPtrField<
|
|
::chromeos_update_engine::InstallOperation>& operations,
|
|
const ::google::protobuf::RepeatedPtrField<CowMergeOperation>&
|
|
merge_operations) {
|
|
ExtentRanges merge_extents;
|
|
std::vector<CowOperation> converted;
|
|
|
|
// We want all CowCopy ops to be done first, before any COW_REPLACE happen.
|
|
// Therefore we add these ops in 2 separate loops. This is because during
|
|
// merge, a CowReplace might modify a block needed by CowCopy, so we always
|
|
// perform CowCopy first.
|
|
|
|
// This loop handles CowCopy blocks within SOURCE_COPY, and the next loop
|
|
// converts the leftover blocks to CowReplace?
|
|
for (const auto& merge_op : merge_operations) {
|
|
if (merge_op.type() != CowMergeOperation::COW_COPY) {
|
|
continue;
|
|
}
|
|
merge_extents.AddExtent(merge_op.dst_extent());
|
|
const auto& src_extent = merge_op.src_extent();
|
|
const auto& dst_extent = merge_op.dst_extent();
|
|
// Add blocks in reverse order, because snapused specifically prefers this
|
|
// ordering. Since we already eliminated all self-overlapping SOURCE_COPY
|
|
// during delta generation, this should be safe to do.
|
|
for (uint64_t i = src_extent.num_blocks(); i > 0; i--) {
|
|
auto src_block = src_extent.start_block() + i - 1;
|
|
auto dst_block = dst_extent.start_block() + i - 1;
|
|
converted.push_back({CowOperation::CowCopy, src_block, dst_block, 1});
|
|
}
|
|
}
|
|
// COW_REPLACE are added after COW_COPY, because replace might modify blocks
|
|
// needed by COW_COPY. Please don't merge this loop with the previous one.
|
|
for (const auto& operation : operations) {
|
|
if (operation.type() != InstallOperation::SOURCE_COPY) {
|
|
continue;
|
|
}
|
|
const auto& src_extents = operation.src_extents();
|
|
const auto& dst_extents = operation.dst_extents();
|
|
BlockIterator it1{src_extents};
|
|
BlockIterator it2{dst_extents};
|
|
while (!it1.is_end() && !it2.is_end()) {
|
|
const auto src_block = *it1;
|
|
const auto dst_block = *it2;
|
|
if (!merge_extents.ContainsBlock(dst_block)) {
|
|
push_back(&converted,
|
|
{CowOperation::CowReplace, src_block, dst_block, 1});
|
|
}
|
|
++it1;
|
|
++it2;
|
|
}
|
|
}
|
|
return converted;
|
|
}
|
|
} // namespace chromeos_update_engine
|