diff --git a/repos/dde_rump/src/lib/rump/io.cc b/repos/dde_rump/src/lib/rump/io.cc
index 22b4bfde64..952b04260d 100644
--- a/repos/dde_rump/src/lib/rump/io.cc
+++ b/repos/dde_rump/src/lib/rump/io.cc
@@ -314,7 +314,7 @@ void rumpuser_bio(int fd, int op, void *data, size_t dlen, int64_t off,
 	Packet *p = backend()->alloc();
 
 	if (verbose)
-		PDBG("fd: %d op: %d len: %zu off: %lx p %p bio %p sync %u", fd, op, dlen, off,
+		PDBG("fd: %d op: %d len: %zu off: %lx p %p bio %p sync %u", fd, op, dlen, (unsigned long)off,
 		     p, donearg, !!(op & RUMPUSER_BIO_SYNC));
 
 	p->opcode= op & RUMPUSER_BIO_WRITE ? Block::Packet_descriptor::WRITE :
diff --git a/repos/libports/src/server/ffat_fs/util.h b/repos/libports/src/server/ffat_fs/util.h
index f7988b10e3..d28ad4f0b6 100644
--- a/repos/libports/src/server/ffat_fs/util.h
+++ b/repos/libports/src/server/ffat_fs/util.h
@@ -10,6 +10,7 @@
 
 /* Genode includes */
 #include <util/string.h>
+#include <file_system/util.h>
 
 
 /**
@@ -40,18 +41,6 @@ static inline bool is_basename(char const *path)
 }
 
 
-/**
- * Return true if character 'c' occurs in null-terminated string 'str'
- */
-static inline bool string_contains(char const *str, char c)
-{
-	for (; *str; str++)
-		if (*str == c)
-			return true;
-	return false;
-}
-
-
 /**
  * Return true if null-terminated string 'substr' occurs in null-terminated
  * string 'str'
@@ -85,9 +74,9 @@ static inline bool valid_filename(char const *str)
 	if (str[0] == 0) return false;
 
 	/* must not contain '/' or '\' or ':' */
-	if (string_contains(str, '/') ||
-	    string_contains(str, '\\') ||
-	    string_contains(str, ':'))
+	if (File_system::string_contains(str, '/') ||
+	    File_system::string_contains(str, '\\') ||
+	    File_system::string_contains(str, ':'))
 		return false;
 
 	return true;
@@ -105,8 +94,8 @@ static inline bool valid_path(char const *str)
 		return false;
 
 	/* must not contain '\' or ':' */
-	if (string_contains(str, '\\') ||
-	    string_contains(str, ':'))
+	if (File_system::string_contains(str, '\\') ||
+	    File_system::string_contains(str, ':'))
 		return false;
 
 	/* must not contain "/../" */
diff --git a/repos/libports/src/server/fuse_fs/util.h b/repos/libports/src/server/fuse_fs/util.h
index f7988b10e3..d28ad4f0b6 100644
--- a/repos/libports/src/server/fuse_fs/util.h
+++ b/repos/libports/src/server/fuse_fs/util.h
@@ -10,6 +10,7 @@
 
 /* Genode includes */
 #include <util/string.h>
+#include <file_system/util.h>
 
 
 /**
@@ -40,18 +41,6 @@ static inline bool is_basename(char const *path)
 }
 
 
-/**
- * Return true if character 'c' occurs in null-terminated string 'str'
- */
-static inline bool string_contains(char const *str, char c)
-{
-	for (; *str; str++)
-		if (*str == c)
-			return true;
-	return false;
-}
-
-
 /**
  * Return true if null-terminated string 'substr' occurs in null-terminated
  * string 'str'
@@ -85,9 +74,9 @@ static inline bool valid_filename(char const *str)
 	if (str[0] == 0) return false;
 
 	/* must not contain '/' or '\' or ':' */
-	if (string_contains(str, '/') ||
-	    string_contains(str, '\\') ||
-	    string_contains(str, ':'))
+	if (File_system::string_contains(str, '/') ||
+	    File_system::string_contains(str, '\\') ||
+	    File_system::string_contains(str, ':'))
 		return false;
 
 	return true;
@@ -105,8 +94,8 @@ static inline bool valid_path(char const *str)
 		return false;
 
 	/* must not contain '\' or ':' */
-	if (string_contains(str, '\\') ||
-	    string_contains(str, ':'))
+	if (File_system::string_contains(str, '\\') ||
+	    File_system::string_contains(str, ':'))
 		return false;
 
 	/* must not contain "/../" */
diff --git a/repos/os/include/file_system/util.h b/repos/os/include/file_system/util.h
index b8474c88ec..f16562818a 100644
--- a/repos/os/include/file_system/util.h
+++ b/repos/os/include/file_system/util.h
@@ -7,57 +7,237 @@
 #ifndef _FILE_SYSTEM__UTIL_H_
 #define _FILE_SYSTEM__UTIL_H_
 
-/**
- * Return base-name portion of null-terminated path string
- */
-static inline char const *basename(char const *path)
-{
-	char const *start = path;
+#include <file_system_session/file_system_session.h>
+#include <os/path.h>
 
-	for (; *path; path++)
-		if (*path == '/')
-			start = path + 1;
+namespace File_system {
 
-	return start;
-}
+	/**
+	 * Return true if character 'c' occurs in null-terminated string 'str'
+	*/
+	inline bool string_contains(char const *str, char c)
+	{
+		for (; *str; str++)
+			if (*str == c)
+				return true;
+		return false;
+	}
+
+	/**
+	 * Return base-name portion of null-terminated path string
+	 */
+	static inline char const *basename(char const *path)
+	{
+		char const *start = path;
+
+		for (; *path; path++)
+			if (*path == '/')
+				start = path + 1;
+
+		return start;
+	}
 
 
-/**
- * Return true if specified path is a base name (contains no path delimiters)
- */
-static inline bool is_basename(char const *path)
-{
-	for (; *path; path++)
-		if (*path == '/')
-			return false;
+	/**
+	 * Return true if specified path is a base name (contains no path delimiters)
+	 */
+	static inline bool is_basename(char const *path)
+	{
+		for (; *path; path++)
+			if (*path == '/')
+				return false;
 
-	return true;
-}
+		return true;
+	}
 
 
-/**
- * Return true if character 'c' occurs in null-terminated string 'str'
- */
-static inline bool string_contains(char const *str, char c)
-{
-	for (; *str; str++)
-		if (*str == c)
-			return true;
-	return false;
-}
+	/**
+	 * Return true if 'str' is a valid node name
+	 */
+	static inline bool valid_name(char const *str)
+	{
+		if (string_contains(str, '/')) return false;
+
+		/* must have at least one character */
+		if (str[0] == 0) return false;
+
+		return true;
+	}
 
 
-/**
- * Return true if 'str' is a valid node name
- */
-static inline bool valid_name(char const *str)
-{
-	if (string_contains(str, '/')) return false;
+	/**
+	 * Open a directory, ensuring all parent directories exists.
+	 */
+	static inline Dir_handle ensure_dir(Session &fs, char const *path)
+	{
+		try {
+			return fs.dir(path, false);
+		} catch (Lookup_failed) {
+			try {
+				return fs.dir(path, true);
+			} catch (Lookup_failed) {
+				Genode::Path<MAX_PATH_LEN> target(path);
+				target.strip_last_element();
+				target.remove_trailing('/');
+				fs.close(ensure_dir(fs, target.base()));
+			}
+		}
+		return fs.dir(path, true);
+	}
 
-	/* must have at least one character */
-	if (str[0] == 0) return false;
 
-	return true;
+	/**
+	 * Collect pending packet acknowledgements, freeing the space occupied
+	 * by the packet in the bulk buffer
+	 *
+	 * This function should be called prior enqueing new packets into the
+	 * packet stream to free up space in the bulk buffer.
+	 */
+	static void collect_acknowledgements(Session::Tx::Source &source)
+	{
+		while (source.ack_avail())
+			source.release_packet(source.get_acked_packet());
+	}
+
+
+	/**
+	 * Read file content
+	 */
+	static inline size_t read(Session &fs, File_handle const &file_handle,
+	                          void *dst, size_t count, seek_off_t seek_offset = 0)
+	{
+		bool success = true;
+		Session::Tx::Source &source = *fs.tx();
+
+		size_t const max_packet_size = source.bulk_buffer_size() / 2;
+
+		size_t remaining_count = count;
+
+		while (remaining_count && success) {
+
+			collect_acknowledgements(source);
+
+			size_t const curr_packet_size = min(remaining_count, max_packet_size);
+
+			Packet_descriptor
+				packet(source.alloc_packet(curr_packet_size),
+				       0,
+				       file_handle,
+				       File_system::Packet_descriptor::READ,
+				       curr_packet_size,
+				       seek_offset);
+
+			/* pass packet to server side */
+			source.submit_packet(packet);
+
+			packet = source.get_acked_packet();
+			success = packet.succeeded();
+
+			size_t const read_num_bytes = min(packet.length(), curr_packet_size);
+
+			/* copy-out payload into destination buffer */
+			memcpy(dst, source.packet_content(packet), read_num_bytes);
+
+			source.release_packet(packet);
+
+			/* prepare next iteration */
+			seek_offset += read_num_bytes;
+			dst = (void *)((Genode::addr_t)dst + read_num_bytes);
+			remaining_count -= read_num_bytes;
+
+			/*
+			 * If we received less bytes than requested, we reached the end
+			 * of the file.
+			 */
+			if (read_num_bytes < curr_packet_size)
+				break;
+		}
+
+		return count - remaining_count;
+	}
+
+
+	/**
+	 * Write file content
+	 */
+	static inline size_t write(Session &fs, File_handle const &file_handle,
+	                          void const *src, size_t count, seek_off_t seek_offset = 0)
+	{
+		bool success = true;
+		Session::Tx::Source &source = *fs.tx();
+
+		size_t const max_packet_size = source.bulk_buffer_size() / 2;
+
+		size_t remaining_count = count;
+
+		while (remaining_count && success) {
+
+			collect_acknowledgements(source);
+
+			size_t const curr_packet_size = min(remaining_count, max_packet_size);
+
+			Packet_descriptor
+				packet(source.alloc_packet(curr_packet_size),
+				       0,
+				       file_handle,
+				       File_system::Packet_descriptor::WRITE,
+				       curr_packet_size,
+				       seek_offset);
+
+			/* copy-out source buffer into payload */
+			memcpy(source.packet_content(packet), src, curr_packet_size);
+
+			/* pass packet to server side */
+			source.submit_packet(packet);
+
+			packet = source.get_acked_packet();;
+			success = packet.succeeded();
+			source.release_packet(packet);
+
+			/* prepare next iteration */
+			seek_offset += curr_packet_size;
+			src = (void *)((Genode::addr_t)src + curr_packet_size);
+			remaining_count -= curr_packet_size;
+		}
+
+		return count - remaining_count;
+	}
+
+
+	class Handle_guard
+	{
+		private:
+
+			Session     &_session;
+			Node_handle  _handle;
+
+		public:
+
+			Handle_guard(Session &session, Node_handle handle)
+			: _session(session), _handle(handle) { }
+
+			~Handle_guard() { _session.close(_handle); }
+	};
+
+	class Packet_guard
+	{
+		private:
+
+			Session::Tx::Source           &_source;
+			File_system::Packet_descriptor _packet;
+
+		public:
+
+			Packet_guard(Session::Tx::Source           &source,
+			             File_system::Packet_descriptor packet)
+			: _source(source), _packet(packet) { }
+
+			~Packet_guard()
+			{
+				_source.release_packet(_packet);
+			}
+	};
+
 }
 
 #endif /* _FILE_SYSTEM__UTIL_H_ */
diff --git a/repos/os/include/file_system_session/file_system_session.h b/repos/os/include/file_system_session/file_system_session.h
index 1ed6623cb9..1112fddfa5 100644
--- a/repos/os/include/file_system_session/file_system_session.h
+++ b/repos/os/include/file_system_session/file_system_session.h
@@ -82,6 +82,10 @@ struct File_system::Node_handle
 	Node_handle(int v) : value(v) { }
 
 	bool valid() const { return value != -1; }
+
+	bool operator == (Node_handle const &other) const { return other.value == value; }
+	bool operator != (Node_handle const &other) const { return other.value != value; }
+
 };
 
 
diff --git a/repos/os/src/server/fs_rom/main.cc b/repos/os/src/server/fs_rom/main.cc
index 74f740ca79..389ad3d8cd 100755
--- a/repos/os/src/server/fs_rom/main.cc
+++ b/repos/os/src/server/fs_rom/main.cc
@@ -16,6 +16,7 @@
 #include <root/component.h>
 #include <cap_session/connection.h>
 #include <file_system_session/connection.h>
+#include <file_system/util.h>
 #include <util/arg_string.h>
 #include <base/rpc_server.h>
 #include <base/env.h>
@@ -23,104 +24,6 @@
 #include <os/path.h>
 
 
-/*********************************************
- ** Utilities for accessing the file system **
- *********************************************/
-
-/*
- * XXX The following generic utilities should be moved to a public place.
- *     They are based on those found in the 'libc_fs' plugin. We should
- *     unify them.
- */
-
-namespace File_system {
-
-	/**
-	 * Collect pending packet acknowledgements, freeing the space occupied
-	 * by the packet in the bulk buffer
-	 *
-	 * This function should be called prior enqueing new packets into the
-	 * packet stream to free up space in the bulk buffer.
-	 */
-	static void collect_acknowledgements(Session::Tx::Source &source)
-	{
-		while (source.ack_avail())
-			source.release_packet(source.get_acked_packet());
-	}
-
-
-	/**
-	 * Read file content
-	 */
-	static inline size_t read(Session &fs, File_handle const &file_handle,
-	                          void *dst, size_t count, off_t seek_offset = 0)
-	{
-		Session::Tx::Source &source = *fs.tx();
-
-		size_t const max_packet_size = source.bulk_buffer_size() / 2;
-
-		size_t remaining_count = count;
-
-		while (remaining_count) {
-
-			collect_acknowledgements(source);
-
-			size_t const curr_packet_size = min(remaining_count, max_packet_size);
-
-			Packet_descriptor
-				packet(source.alloc_packet(curr_packet_size),
-				       0,
-				       file_handle,
-				       File_system::Packet_descriptor::READ,
-				       curr_packet_size,
-				       seek_offset);
-
-			/* pass packet to server side */
-			source.submit_packet(packet);
-
-			packet = source.get_acked_packet();
-
-			size_t const read_num_bytes = min(packet.length(), curr_packet_size);
-
-			/* copy-out payload into destination buffer */
-			memcpy(dst, source.packet_content(packet), read_num_bytes);
-
-			source.release_packet(packet);
-
-			/* prepare next iteration */
-			seek_offset += read_num_bytes;
-			dst = (void *)((Genode::addr_t)dst + read_num_bytes);
-			remaining_count -= read_num_bytes;
-
-			/*
-			 * If we received less bytes than requested, we reached the end
-			 * of the file.
-			 */
-			if (read_num_bytes < curr_packet_size)
-				break;
-		}
-
-		return count - remaining_count;
-	}
-
-
-	struct Handle_guard
-	{
-		private:
-
-			Session     &_session;
-			Node_handle  _handle;
-
-		public:
-
-			Handle_guard(Session &session, Node_handle handle)
-			: _session(session), _handle(handle) { }
-
-			~Handle_guard() { _session.close(_handle); }
-	};
-}
-
-
 /*****************
  ** ROM service **
  *****************/
diff --git a/repos/os/src/server/tar_fs/util.h b/repos/os/src/server/tar_fs/util.h
index 3cfcb1eb55..9eae76e78e 100644
--- a/repos/os/src/server/tar_fs/util.h
+++ b/repos/os/src/server/tar_fs/util.h
@@ -17,18 +17,7 @@
 
 /* Genode includes */
 #include <util/string.h>
-
-
-/**
- * Return true if character 'c' occurs in null-terminated string 'str'
- */
-static inline bool string_contains(char const *str, char c)
-{
-	for (; *str; str++)
-		if (*str == c)
-			return true;
-	return false;
-}
+#include <file_system/util.h>
 
 
 /**
@@ -64,9 +53,9 @@ static inline bool valid_filename(char const *str)
 	if (str[0] == 0) return false;
 
 	/* must not contain '/' or '\' or ':' */
-	if (string_contains(str, '/') ||
-	    string_contains(str, '\\') ||
-	    string_contains(str, ':'))
+	if (File_system::string_contains(str, '/') ||
+	    File_system::string_contains(str, '\\') ||
+	    File_system::string_contains(str, ':'))
 		return false;
 
 	return true;
@@ -85,8 +74,8 @@ static inline bool valid_path(char const *str)
 		return false;
 
 	/* must not contain '\' or ':' */
-	if (string_contains(str, '\\') ||
-	    string_contains(str, ':'))
+	if (File_system::string_contains(str, '\\') ||
+	    File_system::string_contains(str, ':'))
 		return false;
 
 	/* must not contain "/../" */
diff --git a/repos/os/src/server/trace_fs/main.cc b/repos/os/src/server/trace_fs/main.cc
index 854a42d5f0..eed11e9bbe 100644
--- a/repos/os/src/server/trace_fs/main.cc
+++ b/repos/os/src/server/trace_fs/main.cc
@@ -25,6 +25,7 @@
 #include <util/list.h>
 #include <util/string.h>
 #include <util/xml_node.h>
+#include <file_system/util.h>
 
 /* local includes */
 #include <buffer.h>
@@ -47,9 +48,9 @@ static inline bool valid_filename(char const *str)
 	if (str[0] == 0) return false;
 
 	/* must not contain '/' or '\' or ':' */
-	if (string_contains(str, '/') ||
-		string_contains(str, '\\') ||
-		string_contains(str, ':'))
+	if (File_system::string_contains(str, '/') ||
+		File_system::string_contains(str, '\\') ||
+		File_system::string_contains(str, ':'))
 		return false;
 
 	return true;