diff --git a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
index 70e1dc8..eb6ad05 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h
@@ -39,11 +39,9 @@
                  std::string* snapshot_path),
                 (override));
     MOCK_METHOD(std::unique_ptr<ICowWriter>, OpenSnapshotWriter,
-                (const std::string& partition_name, std::chrono::milliseconds timeout_ms),
-                (override));
+                (const android::fs_mgr::CreateLogicalPartitionParams& params), (override));
     MOCK_METHOD(std::unique_ptr<FileDescriptor>, OpenSnapshotReader,
-                (const std::string& partition_name, std::chrono::milliseconds timeout_ms),
-                (override));
+                (const android::fs_mgr::CreateLogicalPartitionParams& params), (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 dacdb1e..6fef58a 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -187,14 +187,15 @@
     virtual bool MapUpdateSnapshot(const android::fs_mgr::CreateLogicalPartitionParams& params,
                                    std::string* snapshot_path) = 0;
 
-    // Create an ICowWriter to build a snapshot against a target partition.
+    // Create an ICowWriter to build a snapshot against a target partition. The partition name must
+    // be suffixed.
     virtual std::unique_ptr<ICowWriter> OpenSnapshotWriter(
-            const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) = 0;
+            const android::fs_mgr::CreateLogicalPartitionParams& params) = 0;
 
     // Open a snapshot for reading. A file-like interface is provided through the FileDescriptor.
-    // In this mode, writes are not supported.
+    // In this mode, writes are not supported. The partition name must be suffixed.
     virtual std::unique_ptr<FileDescriptor> OpenSnapshotReader(
-            const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) = 0;
+            const android::fs_mgr::CreateLogicalPartitionParams& params) = 0;
 
     // Unmap a snapshot device or CowWriter that was previously opened with MapUpdateSnapshot,
     // OpenSnapshotWriter, or OpenSnapshotReader. All outstanding open descriptors, writers,
@@ -310,9 +311,9 @@
     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;
+            const android::fs_mgr::CreateLogicalPartitionParams& params) override;
     std::unique_ptr<FileDescriptor> OpenSnapshotReader(
-            const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) override;
+            const android::fs_mgr::CreateLogicalPartitionParams& params) 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 f70cc92..149f463 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h
@@ -36,10 +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<ICowWriter> OpenSnapshotWriter(
+            const android::fs_mgr::CreateLogicalPartitionParams& params) override;
     std::unique_ptr<FileDescriptor> OpenSnapshotReader(
-            const std::string& partition_name, std::chrono::milliseconds timeout_ms = {}) override;
+            const android::fs_mgr::CreateLogicalPartitionParams& params) 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 a74f984..0904fc7 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -2442,25 +2442,18 @@
 }
 
 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;
-    }
+        const android::fs_mgr::CreateLogicalPartitionParams& params) {
+    (void)params;
 
-    (void)partition_name;
-    (void)timeout_ms;
-
-    // Not yet implemented.
+    LOG(ERROR) << "OpenSnapshotWriter 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;
+        const android::fs_mgr::CreateLogicalPartitionParams& params) {
+    (void)params;
 
-    // Not yet implemented.
+    LOG(ERROR) << "OpenSnapshotReader not yet implemented";
     return nullptr;
 }
 
diff --git a/fs_mgr/libsnapshot/snapshot_stub.cpp b/fs_mgr/libsnapshot/snapshot_stub.cpp
index 269dd09..8ae6305 100644
--- a/fs_mgr/libsnapshot/snapshot_stub.cpp
+++ b/fs_mgr/libsnapshot/snapshot_stub.cpp
@@ -130,14 +130,14 @@
     return &snapshot_merge_stats;
 }
 
-std::unique_ptr<ICowWriter> SnapshotManagerStub::OpenSnapshotWriter(const std::string&,
-                                                                    std::chrono::milliseconds) {
+std::unique_ptr<ICowWriter> SnapshotManagerStub::OpenSnapshotWriter(
+        const CreateLogicalPartitionParams&) {
     LOG(ERROR) << __FUNCTION__ << " should never be called.";
     return nullptr;
 }
 
-std::unique_ptr<FileDescriptor> SnapshotManagerStub::OpenSnapshotReader(const std::string&,
-                                                                        std::chrono::milliseconds) {
+std::unique_ptr<FileDescriptor> SnapshotManagerStub::OpenSnapshotReader(
+        const CreateLogicalPartitionParams&) {
     LOG(ERROR) << __FUNCTION__ << " should never be called.";
     return nullptr;
 }