Merge "libsnapshot: Prototype the new API for mapping writable snapshots."
diff --git a/fs_mgr/libsnapshot/Android.bp b/fs_mgr/libsnapshot/Android.bp
index 0bb1b87..aa41be3 100644
--- a/fs_mgr/libsnapshot/Android.bp
+++ b/fs_mgr/libsnapshot/Android.bp
@@ -30,6 +30,7 @@
static_libs: [
"libdm",
"libfstab",
+ "libsnapshot_cow",
"update_metadata-protos",
],
whole_static_libs: [
@@ -38,7 +39,9 @@
"libfstab",
],
header_libs: [
+ "libchrome",
"libfiemap_headers",
+ "libupdate_engine_headers",
],
export_static_lib_headers: [
"update_metadata-protos",
@@ -313,8 +316,10 @@
"libprotobuf-mutator",
],
header_libs: [
+ "libchrome",
"libfiemap_headers",
"libstorage_literals_headers",
+ "libupdate_engine_headers",
],
proto: {
type: "full",
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
index 4457de3..70e1dc8 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
@@ -15,6 +15,7 @@
#pragma once
#include <libsnapshot/snapshot.h>
+#include <payload_consumer/file_descriptor.h>
#include <gmock/gmock.h>
@@ -37,6 +38,12 @@
(const android::fs_mgr::CreateLogicalPartitionParams& params,
std::string* snapshot_path),
(override));
+ MOCK_METHOD(std::unique_ptr<ICowWriter>, OpenSnapshotWriter,
+ (const std::string& partition_name, std::chrono::milliseconds timeout_ms),
+ (override));
+ MOCK_METHOD(std::unique_ptr<FileDescriptor>, OpenSnapshotReader,
+ (const std::string& partition_name, std::chrono::milliseconds timeout_ms),
+ (override));
MOCK_METHOD(bool, UnmapUpdateSnapshot, (const std::string& target_partition_name), (override));
MOCK_METHOD(bool, NeedSnapshotsInFirstStageMount, (), (override));
MOCK_METHOD(bool, CreateLogicalAndSnapshotPartitions,
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index a4a3150..dacdb1e 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -35,6 +35,7 @@
#include <update_engine/update_metadata.pb.h>
#include <libsnapshot/auto_device.h>
+#include <libsnapshot/cow_writer.h>
#include <libsnapshot/return.h>
#ifndef FRIEND_TEST
@@ -43,6 +44,10 @@
#define DEFINED_FRIEND_TEST
#endif
+namespace chromeos_update_engine {
+class FileDescriptor;
+} // namespace chromeos_update_engine
+
namespace android {
namespace fiemap {
@@ -105,6 +110,8 @@
};
virtual ~ISnapshotManager() = default;
+ using FileDescriptor = chromeos_update_engine::FileDescriptor;
+
// Begin an update. This must be called before creating any snapshots. It
// will fail if GetUpdateState() != None.
virtual bool BeginUpdate() = 0;
@@ -173,11 +180,25 @@
// Map a snapshotted partition for OTA clients to write to. Write-protected regions are
// determined previously in CreateSnapshots.
+ //
// |snapshot_path| must not be nullptr.
+ //
+ // This method will return false if ro.virtual_ab.compression.enabled is true.
virtual bool MapUpdateSnapshot(const android::fs_mgr::CreateLogicalPartitionParams& params,
std::string* snapshot_path) = 0;
- // Unmap a snapshot device that's previously mapped with MapUpdateSnapshot.
+ // Create an ICowWriter to build a snapshot against a target partition.
+ virtual std::unique_ptr<ICowWriter> OpenSnapshotWriter(
+ const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) = 0;
+
+ // Open a snapshot for reading. A file-like interface is provided through the FileDescriptor.
+ // In this mode, writes are not supported.
+ virtual std::unique_ptr<FileDescriptor> OpenSnapshotReader(
+ const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) = 0;
+
+ // Unmap a snapshot device or CowWriter that was previously opened with MapUpdateSnapshot,
+ // OpenSnapshotWriter, or OpenSnapshotReader. All outstanding open descriptors, writers,
+ // or readers must be deleted before this is called.
virtual bool UnmapUpdateSnapshot(const std::string& target_partition_name) = 0;
// If this returns true, first-stage mount must call
@@ -288,6 +309,10 @@
Return CreateUpdateSnapshots(const DeltaArchiveManifest& manifest) override;
bool MapUpdateSnapshot(const CreateLogicalPartitionParams& params,
std::string* snapshot_path) override;
+ std::unique_ptr<ICowWriter> OpenSnapshotWriter(
+ const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) override;
+ std::unique_ptr<FileDescriptor> OpenSnapshotReader(
+ const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) override;
bool UnmapUpdateSnapshot(const std::string& target_partition_name) override;
bool NeedSnapshotsInFirstStageMount() override;
bool CreateLogicalAndSnapshotPartitions(
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
index 7a27fad..f70cc92 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
@@ -15,6 +15,7 @@
#pragma once
#include <libsnapshot/snapshot.h>
+#include <payload_consumer/file_descriptor.h>
namespace android::snapshot {
@@ -35,6 +36,10 @@
const chromeos_update_engine::DeltaArchiveManifest& manifest) override;
bool MapUpdateSnapshot(const android::fs_mgr::CreateLogicalPartitionParams& params,
std::string* snapshot_path) override;
+ std::unique_ptr<ICowWriter> OpenSnapshotWriter(const std::string& partition_name,
+ std::chrono::milliseconds timeout_ms) override;
+ std::unique_ptr<FileDescriptor> OpenSnapshotReader(
+ const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) override;
bool UnmapUpdateSnapshot(const std::string& target_partition_name) override;
bool NeedSnapshotsInFirstStageMount() override;
bool CreateLogicalAndSnapshotPartitions(
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index b49f99e..a74f984 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -27,6 +27,7 @@
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/parseint.h>
+#include <android-base/properties.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include <ext4_utils/ext4_utils.h>
@@ -68,6 +69,7 @@
using android::hardware::boot::V1_1::MergeStatus;
using chromeos_update_engine::DeltaArchiveManifest;
using chromeos_update_engine::Extent;
+using chromeos_update_engine::FileDescriptor;
using chromeos_update_engine::InstallOperation;
template <typename T>
using RepeatedPtrField = google::protobuf::RepeatedPtrField<T>;
@@ -103,6 +105,10 @@
metadata_dir_ = device_->GetMetadataDir();
}
+static inline bool IsCompressionEnabled() {
+ return android::base::GetBoolProperty("ro.virtual_ab.compression.enabled", false);
+}
+
static std::string GetCowName(const std::string& snapshot_name) {
return snapshot_name + "-cow";
}
@@ -2420,6 +2426,11 @@
bool SnapshotManager::MapUpdateSnapshot(const CreateLogicalPartitionParams& params,
std::string* snapshot_path) {
+ if (IsCompressionEnabled()) {
+ LOG(ERROR) << "MapUpdateSnapshot cannot be used in compression mode.";
+ return false;
+ }
+
auto lock = LockShared();
if (!lock) return false;
if (!UnmapPartitionWithSnapshot(lock.get(), params.GetPartitionName())) {
@@ -2430,6 +2441,29 @@
return MapPartitionWithSnapshot(lock.get(), params, snapshot_path);
}
+std::unique_ptr<ICowWriter> SnapshotManager::OpenSnapshotWriter(
+ const std::string& partition_name, std::chrono::milliseconds timeout_ms) {
+ if (!IsCompressionEnabled()) {
+ LOG(ERROR) << "OpenSnapshotWriter can only be called in compression mode.";
+ return nullptr;
+ }
+
+ (void)partition_name;
+ (void)timeout_ms;
+
+ // Not yet implemented.
+ return nullptr;
+}
+
+std::unique_ptr<FileDescriptor> SnapshotManager::OpenSnapshotReader(
+ const std::string& partition_name, std::chrono::milliseconds timeout_ms) {
+ (void)partition_name;
+ (void)timeout_ms;
+
+ // Not yet implemented.
+ return nullptr;
+}
+
bool SnapshotManager::UnmapUpdateSnapshot(const std::string& target_partition_name) {
auto lock = LockShared();
if (!lock) return false;
diff --git a/fs_mgr/libsnapshot/snapshot_stub.cpp b/fs_mgr/libsnapshot/snapshot_stub.cpp
index 9b6f758..269dd09 100644
--- a/fs_mgr/libsnapshot/snapshot_stub.cpp
+++ b/fs_mgr/libsnapshot/snapshot_stub.cpp
@@ -20,6 +20,7 @@
using android::fs_mgr::CreateLogicalPartitionParams;
using chromeos_update_engine::DeltaArchiveManifest;
+using chromeos_update_engine::FileDescriptor;
namespace android::snapshot {
@@ -129,4 +130,16 @@
return &snapshot_merge_stats;
}
+std::unique_ptr<ICowWriter> SnapshotManagerStub::OpenSnapshotWriter(const std::string&,
+ std::chrono::milliseconds) {
+ LOG(ERROR) << __FUNCTION__ << " should never be called.";
+ return nullptr;
+}
+
+std::unique_ptr<FileDescriptor> SnapshotManagerStub::OpenSnapshotReader(const std::string&,
+ std::chrono::milliseconds) {
+ LOG(ERROR) << __FUNCTION__ << " should never be called.";
+ return nullptr;
+}
+
} // namespace android::snapshot