diff --git a/include/ircd/fs/write.h b/include/ircd/fs/write.h
index 0853b8219..7e4b8ad3b 100644
--- a/include/ircd/fs/write.h
+++ b/include/ircd/fs/write.h
@@ -30,6 +30,9 @@ namespace ircd::fs
 	// Truncate file to explicit size
 	void truncate(const fd &, const size_t &, const write_opts & = write_opts_default);
 	void truncate(const string_view &path, const size_t &, const write_opts & = write_opts_default);
+
+	// Allocate
+	void allocate(const fd &, const size_t &size, const write_opts & = write_opts_default);
 }
 
 /// Options for a write operation
diff --git a/ircd/fs.cc b/ircd/fs.cc
index 5c5c19d77..a2f3d7131 100644
--- a/ircd/fs.cc
+++ b/ircd/fs.cc
@@ -383,6 +383,14 @@ ircd::fs::write_opts
 const ircd::fs::write_opts_default
 {};
 
+void
+ircd::fs::allocate(const fd &fd,
+                   const size_t &size,
+                   const write_opts &opts)
+{
+	syscall(::posix_fallocate, fd, opts.offset, size);
+}
+
 void
 ircd::fs::truncate(const string_view &path,
                    const size_t &size,