Merge "Shove CowOperation type into source_info" into main (240f7084) · Commits · e / os / android_system_core

fs_mgr/libsnapshot/include/libsnapshot/cow_format.h

+28 −11

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@
		#include <limits>
		#include <optional>
		#include <string_view>
		#include <type_traits>

		namespace android {
		namespace snapshot {
		@@ -194,11 +195,12 @@ struct CowOperationV2 {
		uint64_t source;
		} __attribute__((packed));

		static constexpr uint64_t kCowOpSourceInfoDataMask = (1ULL << 48) - 1;
		static constexpr uint64_t kCowOpSourceInfoTypeBit = 60;
		static constexpr uint64_t kCowOpSourceInfoTypeNumBits = 4;
		static constexpr uint64_t kCowOpSourceInfoTypeMask = (1ULL << kCowOpSourceInfoTypeNumBits) - 1;
		// The on disk format of cow (currently == CowOperation)
		struct CowOperationV3 {
		// The operation code (see the constants and structures below).
		CowOperationType type;

		// If this operation reads from the data section of the COW, this contains
		// the length.
		uint16_t data_length;
		@@ -206,6 +208,10 @@ struct CowOperationV3 {
		// The block of data in the new image that this operation modifies.
		uint32_t new_block;

		// source_info with have the following layout
		// \|---4 bits ---\| ---12 bits---\| --- 48 bits ---\|
		// \|--- type --- \| -- unused -- \| --- source --- \|
		//
		// The value of \|source\| depends on the operation code.
		//
		// CopyOp: a 32-bit block location in the source image.
		@@ -217,9 +223,26 @@ struct CowOperationV3 {
		// For ops other than Label:
		// Bits 47-62 are reserved and must be zero.
		// A block is compressed if it’s data is < block_sz
		uint64_t source_info;
		uint64_t source_info_;
		constexpr uint64_t source() const { return source_info_ & kCowOpSourceInfoDataMask; }
		constexpr void set_source(uint64_t source) {
		source_info_ \|= source & kCowOpSourceInfoDataMask;
		}
		constexpr CowOperationType type() const {
		// this is a mask to grab the first 4 bits of a 64 bit integer
		const auto type = (source_info_ >> kCowOpSourceInfoTypeBit) & kCowOpSourceInfoTypeMask;
		return static_cast<CowOperationType>(type);
		}
		constexpr void set_type(CowOperationType type) {
		source_info_ \|= (static_cast<uint64_t>(type) & kCowOpSourceInfoTypeMask)
		<< kCowOpSourceInfoTypeBit;
		}
		} __attribute__((packed));

		// Ensure that getters/setters added to CowOperationV3 does not increases size
		// of CowOperationV3 struct(no virtual method tables added).
		static_assert(std::is_trivially_copyable_v<CowOperationV3>);
		static_assert(std::is_standard_layout_v<CowOperationV3>);
		static_assert(sizeof(CowOperationV2) == sizeof(CowFooterOperation));

		enum CowCompressionAlgorithm : uint8_t {
		@@ -238,12 +261,6 @@ static constexpr uint8_t kCowReadAheadNotStarted = 0;
		static constexpr uint8_t kCowReadAheadInProgress = 1;
		static constexpr uint8_t kCowReadAheadDone = 2;

		static constexpr uint64_t kCowOpSourceInfoDataMask = (1ULL << 48) - 1;

		static inline uint64_t GetCowOpSourceInfoData(const CowOperation& op) {
		return op.source_info & kCowOpSourceInfoDataMask;
		}

		static constexpr off_t GetSequenceOffset(const CowHeaderV3& header) {
		return header.prefix.header_size + header.buffer_size;
		}
		@@ -284,7 +301,7 @@ static constexpr uint64_t BUFFER_REGION_DEFAULT_SIZE = (1ULL << 21);

		std::ostream& operator<<(std::ostream& os, CowOperationV2 const& arg);

		std::ostream& operator<<(std::ostream& os, CowOperation const& arg);
		std::ostream& operator<<(std::ostream& os, CowOperationV3 const& arg);

		std::ostream& operator<<(std::ostream& os, ResumePoint const& arg);

fs_mgr/libsnapshot/libsnapshot_cow/cow_format.cpp

+11 −12

Original line number	Diff line number	Diff line
		@@ -80,22 +80,21 @@ std::ostream& operator<<(std::ostream& os, CowOperationV2 const& op) {
		return os;
		}

		std::ostream& operator<<(std::ostream& os, CowOperation const& op) {
		std::ostream& operator<<(std::ostream& os, CowOperationV3 const& op) {
		os << "CowOperation(";
		EmitCowTypeString(os, op.type);
		if (op.type == kCowReplaceOp \|\| op.type == kCowXorOp \|\| op.type == kCowSequenceOp) {
		EmitCowTypeString(os, op.type());
		if (op.type() == kCowReplaceOp \|\| op.type() == kCowXorOp \|\| op.type() == kCowSequenceOp) {
		os << ", data_length:" << op.data_length;
		}
		if (op.type != kCowClusterOp && op.type != kCowSequenceOp && op.type != kCowLabelOp) {
		if (op.type() != kCowClusterOp && op.type() != kCowSequenceOp && op.type() != kCowLabelOp) {
		os << ", new_block:" << op.new_block;
		}
		if (op.type == kCowXorOp \|\| op.type == kCowReplaceOp \|\| op.type == kCowCopyOp) {
		os << ", source:" << (op.source_info & kCowOpSourceInfoDataMask);
		} else if (op.type == kCowClusterOp) {
		os << ", cluster_data:" << (op.source_info & kCowOpSourceInfoDataMask);
		} else {
		os << ", label:0x" << android::base::StringPrintf("%" PRIx64, op.source_info);
		if (op.type() == kCowXorOp \|\| op.type() == kCowReplaceOp \|\| op.type() == kCowCopyOp) {
		os << ", source:" << op.source();
		} else if (op.type() == kCowClusterOp) {
		os << ", cluster_data:" << op.source();
		}
		// V3 op stores resume points in header, so CowOp can never be Label.
		os << ")";
		return os;
		}
		@@ -126,7 +125,7 @@ int64_t GetNextDataOffset(const CowOperationV2& op, uint32_t cluster_ops) {
		}

		bool IsMetadataOp(const CowOperation& op) {
		switch (op.type) {
		switch (op.type()) {
		case kCowLabelOp:
		case kCowClusterOp:
		case kCowFooterOp:
		@@ -138,7 +137,7 @@ bool IsMetadataOp(const CowOperation& op) {
		}

		bool IsOrderedOp(const CowOperation& op) {
		switch (op.type) {
		switch (op.type()) {
		case kCowCopyOp:
		case kCowXorOp:
		return true;

fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp

+8 −8

Original line number	Diff line number	Diff line
		@@ -345,7 +345,7 @@ bool CowReader::GetSequenceDataV2(std::vector<uint32_t>* merge_op_blocks,
		for (size_t i = 0; i < ops_->size(); i++) {
		auto& current_op = ops_->data()[i];

		if (current_op.type == kCowSequenceOp) {
		if (current_op.type() == kCowSequenceOp) {
		size_t seq_len = current_op.data_length / sizeof(uint32_t);

		merge_op_blocks->resize(merge_op_blocks->size() + seq_len);
		@@ -637,11 +637,11 @@ std::unique_ptr<ICowOpIter> CowReader::GetMergeOpIter(bool ignore_progress) {
		}

		bool CowReader::GetRawBytes(const CowOperation* op, void* buffer, size_t len, size_t* read) {
		switch (op->type) {
		switch (op->type()) {
		case kCowSequenceOp:
		case kCowReplaceOp:
		case kCowXorOp:
		return GetRawBytes(GetCowOpSourceInfoData(*op), buffer, len, read);
		return GetRawBytes(op->source(), buffer, len, read);
		default:
		LOG(ERROR) << "Cannot get raw bytes of non-data op: " << *op;
		return false;
		@@ -730,10 +730,10 @@ ssize_t CowReader::ReadData(const CowOperation* op, void* buffer, size_t buffer_
		}

		uint64_t offset;
		if (op->type == kCowXorOp) {
		if (op->type() == kCowXorOp) {
		offset = xor_data_loc_->at(op->new_block);
		} else {
		offset = GetCowOpSourceInfoData(*op);
		offset = op->source();
		}
		if (!decompressor \|\|
		((op->data_length == header_.block_size) && (header_.prefix.major_version == 3))) {
		@@ -747,12 +747,12 @@ ssize_t CowReader::ReadData(const CowOperation* op, void* buffer, size_t buffer_
		}

		bool CowReader::GetSourceOffset(const CowOperation* op, uint64_t* source_offset) {
		switch (op->type) {
		switch (op->type()) {
		case kCowCopyOp:
		source_offset = GetCowOpSourceInfoData(op) * header_.block_size;
		source_offset = op->source() header_.block_size;
		return true;
		case kCowXorOp:
		source_offset = GetCowOpSourceInfoData(op);
		*source_offset = op->source();
		return true;
		default:
		return false;

fs_mgr/libsnapshot/libsnapshot_cow/inspect_cow.cpp

+7 −7

Original line number	Diff line number	Diff line
		@@ -199,7 +199,7 @@ static bool Inspect(const std::string& path) {

		if (!FLAGS_silent && FLAGS_show_ops) std::cout << *op << "\n";

		if ((FLAGS_decompress \|\| extract_to >= 0) && op->type == kCowReplaceOp) {
		if ((FLAGS_decompress \|\| extract_to >= 0) && op->type() == kCowReplaceOp) {
		if (reader.ReadData(op, buffer.data(), buffer.size()) < 0) {
		std::cerr << "Failed to decompress for :" << *op << "\n";
		success = false;
		@@ -213,12 +213,12 @@ static bool Inspect(const std::string& path) {
		return false;
		}
		}
		} else if (extract_to >= 0 && !IsMetadataOp(*op) && op->type != kCowZeroOp) {
		} else if (extract_to >= 0 && !IsMetadataOp(*op) && op->type() != kCowZeroOp) {
		PLOG(ERROR) << "Cannot extract op yet: " << *op;
		return false;
		}

		if (op->type == kCowSequenceOp && FLAGS_show_merge_sequence) {
		if (op->type() == kCowSequenceOp && FLAGS_show_merge_sequence) {
		size_t read;
		std::vector<uint32_t> merge_op_blocks;
		size_t seq_len = op->data_length / sizeof(uint32_t);
		@@ -236,13 +236,13 @@ static bool Inspect(const std::string& path) {
		}
		}

		if (op->type == kCowCopyOp) {
		if (op->type() == kCowCopyOp) {
		copy_ops++;
		} else if (op->type == kCowReplaceOp) {
		} else if (op->type() == kCowReplaceOp) {
		replace_ops++;
		} else if (op->type == kCowZeroOp) {
		} else if (op->type() == kCowZeroOp) {
		zero_ops++;
		} else if (op->type == kCowXorOp) {
		} else if (op->type() == kCowXorOp) {
		xor_ops++;
		}

fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.cpp

+3 −3

Original line number	Diff line number	Diff line
		@@ -205,7 +205,7 @@ bool CowParserV2::Translate(TranslatedCowOps* out) {
		const auto& v2_op = v2_ops_->at(i);

		auto& new_op = out->ops->at(i);
		new_op.type = v2_op.type;
		new_op.set_type(v2_op.type);
		new_op.data_length = v2_op.data_length;

		if (v2_op.new_block > std::numeric_limits<uint32_t>::max()) {
		@@ -215,7 +215,7 @@ bool CowParserV2::Translate(TranslatedCowOps* out) {
		new_op.new_block = v2_op.new_block;

		uint64_t source_info = v2_op.source;
		if (new_op.type != kCowLabelOp) {
		if (new_op.type() != kCowLabelOp) {
		source_info &= kCowOpSourceInfoDataMask;
		if (source_info != v2_op.source) {
		LOG(ERROR) << "Out-of-range source value in COW op: " << v2_op;
		@@ -232,7 +232,7 @@ bool CowParserV2::Translate(TranslatedCowOps* out) {
		return false;
		}
		}
		new_op.source_info = source_info;
		new_op.set_source(source_info);
		}

		out->header = header_;