diff --git a/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h b/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h
index 1d6fd62..2721937 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/cow_reader.h
@@ -188,5 +188,7 @@
     uint8_t compression_type_ = kCowCompressNone;
 };
 
+bool ReadCowHeader(android::base::borrowed_fd fd, CowHeader* header);
+
 }  // namespace snapshot
 }  // namespace android
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp
index c52705c..996037e 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/cow_reader.cpp
@@ -34,6 +34,35 @@
 namespace android {
 namespace snapshot {
 
+bool ReadCowHeader(android::base::borrowed_fd fd, CowHeader* header) {
+    if (lseek(fd.get(), 0, SEEK_SET) < 0) {
+        PLOG(ERROR) << "lseek header failed";
+        return false;
+    }
+
+    memset(header, 0, sizeof(*header));
+
+    if (!android::base::ReadFully(fd, &header->prefix, sizeof(header->prefix))) {
+        return false;
+    }
+    if (header->prefix.magic != kCowMagicNumber) {
+        LOG(ERROR) << "Header Magic corrupted. Magic: " << header->prefix.magic
+                   << "Expected: " << kCowMagicNumber;
+        return false;
+    }
+    if (header->prefix.header_size > sizeof(CowHeader)) {
+        LOG(ERROR) << "Unknown CowHeader size (got " << header->prefix.header_size
+                   << " bytes, expected at most " << sizeof(CowHeader) << " bytes)";
+        return false;
+    }
+
+    if (lseek(fd.get(), 0, SEEK_SET) < 0) {
+        PLOG(ERROR) << "lseek header failed";
+        return false;
+    }
+    return android::base::ReadFully(fd, header, header->prefix.header_size);
+}
+
 CowReader::CowReader(ReaderFlags reader_flag, bool is_merge)
     : fd_(-1),
       header_(),
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.cpp
index 8edeae1..a7307bf 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.cpp
@@ -23,35 +23,6 @@
 
 using android::base::borrowed_fd;
 
-bool ReadCowHeader(android::base::borrowed_fd fd, CowHeader* header) {
-    if (lseek(fd.get(), 0, SEEK_SET) < 0) {
-        PLOG(ERROR) << "lseek header failed";
-        return false;
-    }
-
-    memset(header, 0, sizeof(*header));
-
-    if (!android::base::ReadFully(fd, &header->prefix, sizeof(header->prefix))) {
-        return false;
-    }
-    if (header->prefix.magic != kCowMagicNumber) {
-        LOG(ERROR) << "Header Magic corrupted. Magic: " << header->prefix.magic
-                   << "Expected: " << kCowMagicNumber;
-        return false;
-    }
-    if (header->prefix.header_size > sizeof(CowHeader)) {
-        LOG(ERROR) << "Unknown CowHeader size (got " << header->prefix.header_size
-                   << " bytes, expected at most " << sizeof(CowHeader) << " bytes)";
-        return false;
-    }
-
-    if (lseek(fd.get(), 0, SEEK_SET) < 0) {
-        PLOG(ERROR) << "lseek header failed";
-        return false;
-    }
-    return android::base::ReadFully(fd, header, header->prefix.header_size);
-}
-
 bool CowParserV2::Parse(borrowed_fd fd, const CowHeader& header, std::optional<uint64_t> label) {
     auto pos = lseek(fd.get(), 0, SEEK_END);
     if (pos < 0) {
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.h b/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.h
index 92e2b08..f51ff88 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.h
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/parser_v2.h
@@ -49,7 +49,5 @@
     std::optional<uint64_t> last_label_;
 };
 
-bool ReadCowHeader(android::base::borrowed_fd fd, CowHeader* header);
-
 }  // namespace snapshot
 }  // namespace android