diff --git a/sysdeps/mach/hurd/bits/fcntl.h b/sysdeps/mach/hurd/bits/fcntl.h
index 9d598a1..3202971 100644
--- a/sysdeps/mach/hurd/bits/fcntl.h
+++ b/sysdeps/mach/hurd/bits/fcntl.h
@@ -1,5 +1,5 @@
 /* O_*, F_*, FD_* bit values for GNU.
-   Copyright (C) 1993-2013 Free Software Foundation, Inc.
+   Copyright (C) 1993-2014 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -163,9 +163,18 @@
 # define F_GETOWN	5	/* Get owner (receiver of SIGIO).  */
 # define F_SETOWN	6	/* Set owner (receiver of SIGIO).  */
 #endif
+#ifdef __USE_FILE_OFFSET64
+#define	F_GETLK		F_GETLK64
+#define	F_SETLK		F_SETLK64
+#define	F_SETLKW	F_SETLKW64
+#else
 #define	F_GETLK		7	/* Get record locking info.  */
 #define	F_SETLK		8	/* Set record locking info (non-blocking).  */
 #define	F_SETLKW	9	/* Set record locking info (blocking).  */
+#endif
+#define	F_GETLK64	10	/* Get record locking info.  */
+#define	F_SETLK64	11	/* Set record locking info (non-blocking).  */
+#define	F_SETLKW64	12	/* Set record locking info (blocking).  */
 
 #ifdef __USE_XOPEN2K8
 # define F_DUPFD_CLOEXEC 1030	/* Duplicate, set FD_CLOEXEC on new one.  */
diff --git a/sysdeps/mach/hurd/fcntl.c b/sysdeps/mach/hurd/fcntl.c
index 70180fa..7ab58c0 100644
--- a/sysdeps/mach/hurd/fcntl.c
+++ b/sysdeps/mach/hurd/fcntl.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1992-2013 Free Software Foundation, Inc.
+/* Copyright (C) 1992-2014 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -22,6 +22,8 @@
 #include <stdarg.h>
 #include <sys/file.h>		/* XXX for LOCK_* */
 
+#include "flockconv.c"
+
 /* Perform file control operations on FD.  */
 int
 __libc_fcntl (int fd, int cmd, ...)
@@ -180,6 +182,39 @@ __libc_fcntl (int fd, int cmd, ...)
 	return __flock (fd, cmd);
       }
 
+    case F_GETLK64:
+    case F_SETLK64:
+    case F_SETLKW64:
+      {
+	struct flock64 *fl64 = va_arg (ap, struct flock64 *);
+	struct flock fl;
+
+	if (flock64_conv (&fl, fl64))
+	  {
+	    result = -1;
+	    break;
+	  }
+
+	switch (cmd)
+	  {
+	  case F_GETLK64:
+	    result = fcntl (fd, F_GETLK, &fl);
+	    if (flock_conv (fl64, &fl))
+	      result = -1;
+	    break;
+
+	  case F_SETLK64:
+	    result = fcntl (fd, F_SETLK, &fl);
+	    break;
+
+	  case F_SETLKW64:
+	    result = fcntl (fd, F_SETLKW, &fl);
+	    break;
+	  }
+
+	break;
+      }
+
     case F_GETFL:		/* Get per-open flags.  */
       if (err = HURD_FD_PORT_USE (d, __io_get_openmodes (port, &result)))
 	result = __hurd_dfail (fd, err);
diff --git a/sysdeps/mach/hurd/flockconv.c b/sysdeps/mach/hurd/flockconv.c
new file mode 100644
index 0000000..4438784
--- /dev/null
+++ b/sysdeps/mach/hurd/flockconv.c
@@ -0,0 +1,69 @@
+/* Convert between `struct flock' format, and `struct flock64' format.
+   Copyright (C) 2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <fcntl.h>
+
+static inline int
+flock64_conv (struct flock *buf, const struct flock64 *buf64)
+{
+  if (sizeof *buf == sizeof *buf64
+      && sizeof buf->l_start == sizeof buf64->l_start
+      && sizeof buf->l_len == sizeof buf64->l_len)
+    {
+      *buf = *(struct flock *) buf64;
+      return 0;
+    }
+
+  buf->l_type = buf64->l_type;
+  buf->l_whence = buf64->l_whence;
+  buf->l_start = buf64->l_start;
+  buf->l_len = buf64->l_len;
+  buf->l_pid = buf64->l_pid;
+
+  if ((sizeof buf->l_start != sizeof buf64->l_start
+       && buf->l_start != buf64->l_start)
+      || (sizeof buf->l_len != sizeof buf64->l_len
+	  && buf->l_len != buf64->l_len))
+    {
+      __set_errno (EOVERFLOW);
+      return -1;
+    }
+
+  return 0;
+}
+
+static inline int
+flock_conv (struct flock64 *buf64, const struct flock *buf)
+{
+  if (sizeof *buf == sizeof *buf64
+      && sizeof buf->l_start == sizeof buf64->l_start
+      && sizeof buf->l_len == sizeof buf64->l_len)
+    {
+      *buf64 = *(struct flock64 *) buf;
+      return 0;
+    }
+
+  buf64->l_type = buf->l_type;
+  buf64->l_whence = buf->l_whence;
+  buf64->l_start = buf->l_start;
+  buf64->l_len = buf->l_len;
+  buf64->l_pid = buf->l_pid;
+
+  return 0;
+}
