diff --git a/src/unix/notbsd/linux/mod.rs b/src/unix/notbsd/linux/mod.rs
index 4c45991b0a111307a26e24b86fc39d356bd61aad..577814b66f816cf3e736bf4cf918c677f84b74e1 100644
--- a/src/unix/notbsd/linux/mod.rs
+++ b/src/unix/notbsd/linux/mod.rs
@@ -281,6 +281,8 @@ extern {
                     offset: ::off64_t,
                     whence: ::c_int) -> ::c_int;
     pub fn ftello64(stream: *mut ::FILE) -> ::off64_t;
+    pub fn fallocate(fd: ::c_int, mode: ::c_int,
+                     offset: ::off_t, len: ::off_t) -> ::c_int;
 }
 
 cfg_if! {
diff --git a/src/unix/notbsd/linux/notmips/mod.rs b/src/unix/notbsd/linux/notmips/mod.rs
index f974a5638761b1def54dbdc6527abbbec486b361..79c8d5617e2e0fd9f7160f2fe8b5cf45523527fa 100644
--- a/src/unix/notbsd/linux/notmips/mod.rs
+++ b/src/unix/notbsd/linux/notmips/mod.rs
@@ -179,6 +179,9 @@ pub const SIGCHLD: ::c_int = 17;
 pub const SIGBUS: ::c_int = 7;
 pub const SIG_SETMASK: ::c_int = 2;
 
+pub const FALLOC_FL_KEEP_SIZE: ::c_int = 0x01;
+pub const FALLOC_FL_PUNCH_HOLE: ::c_int = 0x02;
+
 extern {
     pub fn getnameinfo(sa: *const ::sockaddr,
                        salen: ::socklen_t,