Initial import if userfaultfd-sys-0.4.2 am: effba4c260 am: 5331a752cd

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/userfaultfd-sys/+/2308667

Change-Id: Ie895c223fa6348150a936f5ff50c10ef281d8131
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

15 files changed, 794 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..63f6535
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,36 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies.
+#
+# If you are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+edition = "2018"
+name = "userfaultfd-sys"
+version = "0.4.2"
+authors = ["Adam C. Foltzer <acfoltzer@fastly.com>"]
+build = "build.rs"
+description = "Low-level bindings for userfaultfd functionality on Linux."
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/fastly/userfaultfd-rs"
+
+[dependencies.cfg-if]
+version = "^1.0.0"
+
+[build-dependencies.bindgen]
+version = "^0.60.1"
+features = ["runtime"]
+default-features = false
+
+[build-dependencies.cc]
+version = "1.0"
+
+[features]
+default = []
+linux4_14 = []
+linux5_7 = []
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..16ac6d1
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,22 @@
+[package]
+name = "userfaultfd-sys"
+version = "0.4.2"
+authors = ["Adam C. Foltzer <acfoltzer@fastly.com>"]
+edition = "2018"
+license = "MIT OR Apache-2.0"
+description = "Low-level bindings for userfaultfd functionality on Linux."
+repository = "https://github.com/fastly/userfaultfd-rs"
+
+build = "build.rs"
+
+[dependencies]
+cfg-if = "^1.0.0"
+
+[build-dependencies]
+bindgen = { version = "^0.60.1", default-features = false, features = ["runtime"]  }
+cc = "1.0"
+
+[features]
+default = []
+linux4_14 = []
+linux5_7 = []
diff --git a/LICENSE b/LICENSE
new file mode 120000
index 0000000..6b579aa
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+LICENSE-APACHE
\ No newline at end of file
diff --git a/LICENSE-APACHE b/LICENSE-APACHE
new file mode 100644
index 0000000..1b5ec8b
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,176 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+   "License" shall mean the terms and conditions for use, reproduction,
+   and distribution as defined by Sections 1 through 9 of this document.
+
+   "Licensor" shall mean the copyright owner or entity authorized by
+   the copyright owner that is granting the License.
+
+   "Legal Entity" shall mean the union of the acting entity and all
+   other entities that control, are controlled by, or are under common
+   control with that entity. For the purposes of this definition,
+   "control" means (i) the power, direct or indirect, to cause the
+   direction or management of such entity, whether by contract or
+   otherwise, or (ii) ownership of fifty percent (50%) or more of the
+   outstanding shares, or (iii) beneficial ownership of such entity.
+
+   "You" (or "Your") shall mean an individual or Legal Entity
+   exercising permissions granted by this License.
+
+   "Source" form shall mean the preferred form for making modifications,
+   including but not limited to software source code, documentation
+   source, and configuration files.
+
+   "Object" form shall mean any form resulting from mechanical
+   transformation or translation of a Source form, including but
+   not limited to compiled object code, generated documentation,
+   and conversions to other media types.
+
+   "Work" shall mean the work of authorship, whether in Source or
+   Object form, made available under the License, as indicated by a
+   copyright notice that is included in or attached to the work
+   (an example is provided in the Appendix below).
+
+   "Derivative Works" shall mean any work, whether in Source or Object
+   form, that is based on (or derived from) the Work and for which the
+   editorial revisions, annotations, elaborations, or other modifications
+   represent, as a whole, an original work of authorship. For the purposes
+   of this License, Derivative Works shall not include works that remain
+   separable from, or merely link (or bind by name) to the interfaces of,
+   the Work and Derivative Works thereof.
+
+   "Contribution" shall mean any work of authorship, including
+   the original version of the Work and any modifications or additions
+   to that Work or Derivative Works thereof, that is intentionally
+   submitted to Licensor for inclusion in the Work by the copyright owner
+   or by an individual or Legal Entity authorized to submit on behalf of
+   the copyright owner. For the purposes of this definition, "submitted"
+   means any form of electronic, verbal, or written communication sent
+   to the Licensor or its representatives, including but not limited to
+   communication on electronic mailing lists, source code control systems,
+   and issue tracking systems that are managed by, or on behalf of, the
+   Licensor for the purpose of discussing and improving the Work, but
+   excluding communication that is conspicuously marked or otherwise
+   designated in writing by the copyright owner as "Not a Contribution."
+
+   "Contributor" shall mean Licensor and any individual or Legal Entity
+   on behalf of whom a Contribution has been received by Licensor and
+   subsequently incorporated within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of
+   this License, each Contributor hereby grants to You a perpetual,
+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   copyright license to reproduce, prepare Derivative Works of,
+   publicly display, publicly perform, sublicense, and distribute the
+   Work and such Derivative Works in Source or Object form.
+
+3. Grant of Patent License. Subject to the terms and conditions of
+   this License, each Contributor hereby grants to You a perpetual,
+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   (except as stated in this section) patent license to make, have made,
+   use, offer to sell, sell, import, and otherwise transfer the Work,
+   where such license applies only to those patent claims licensable
+   by such Contributor that are necessarily infringed by their
+   Contribution(s) alone or by combination of their Contribution(s)
+   with the Work to which such Contribution(s) was submitted. If You
+   institute patent litigation against any entity (including a
+   cross-claim or counterclaim in a lawsuit) alleging that the Work
+   or a Contribution incorporated within the Work constitutes direct
+   or contributory patent infringement, then any patent licenses
+   granted to You under this License for that Work shall terminate
+   as of the date such litigation is filed.
+
+4. Redistribution. You may reproduce and distribute copies of the
+   Work or Derivative Works thereof in any medium, with or without
+   modifications, and in Source or Object form, provided that You
+   meet the following conditions:
+
+   (a) You must give any other recipients of the Work or
+       Derivative Works a copy of this License; and
+
+   (b) You must cause any modified files to carry prominent notices
+       stating that You changed the files; and
+
+   (c) You must retain, in the Source form of any Derivative Works
+       that You distribute, all copyright, patent, trademark, and
+       attribution notices from the Source form of the Work,
+       excluding those notices that do not pertain to any part of
+       the Derivative Works; and
+
+   (d) If the Work includes a "NOTICE" text file as part of its
+       distribution, then any Derivative Works that You distribute must
+       include a readable copy of the attribution notices contained
+       within such NOTICE file, excluding those notices that do not
+       pertain to any part of the Derivative Works, in at least one
+       of the following places: within a NOTICE text file distributed
+       as part of the Derivative Works; within the Source form or
+       documentation, if provided along with the Derivative Works; or,
+       within a display generated by the Derivative Works, if and
+       wherever such third-party notices normally appear. The contents
+       of the NOTICE file are for informational purposes only and
+       do not modify the License. You may add Your own attribution
+       notices within Derivative Works that You distribute, alongside
+       or as an addendum to the NOTICE text from the Work, provided
+       that such additional attribution notices cannot be construed
+       as modifying the License.
+
+   You may add Your own copyright statement to Your modifications and
+   may provide additional or different license terms and conditions
+   for use, reproduction, or distribution of Your modifications, or
+   for any such Derivative Works as a whole, provided Your use,
+   reproduction, and distribution of the Work otherwise complies with
+   the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
+   with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade
+   names, trademarks, service marks, or product names of the Licensor,
+   except as required for reasonable and customary use in describing the
+   origin of the Work and reproducing the content of the NOTICE file.
+
+7. Disclaimer of Warranty. Unless required by applicable law or
+   agreed to in writing, Licensor provides the Work (and each
+   Contributor provides its Contributions) on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+   implied, including, without limitation, any warranties or conditions
+   of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+   PARTICULAR PURPOSE. You are solely responsible for determining the
+   appropriateness of using or redistributing the Work and assume any
+   risks associated with Your exercise of permissions under this License.
+
+8. Limitation of Liability. In no event and under no legal theory,
+   whether in tort (including negligence), contract, or otherwise,
+   unless required by applicable law (such as deliberate and grossly
+   negligent acts) or agreed to in writing, shall any Contributor be
+   liable to You for damages, including any direct, indirect, special,
+   incidental, or consequential damages of any character arising as a
+   result of this License or out of the use or inability to use the
+   Work (including but not limited to damages for loss of goodwill,
+   work stoppage, computer failure or malfunction, or any and all
+   other commercial damages or losses), even if such Contributor
+   has been advised of the possibility of such damages.
+
+9. Accepting Warranty or Additional Liability. While redistributing
+   the Work or Derivative Works thereof, You may choose to offer,
+   and charge a fee for, acceptance of support, warranty, indemnity,
+   or other liability obligations and/or rights consistent with this
+   License. However, in accepting such obligations, You may act only
+   on Your own behalf and on Your sole responsibility, not on behalf
+   of any other Contributor, and only if You agree to indemnify,
+   defend, and hold each Contributor harmless for any liability
+   incurred by, or claims asserted against, such Contributor by reason
+   of your accepting any such warranty or additional liability.
+
+END OF TERMS AND CONDITIONS
diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..31aa793
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..4a8199b
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,20 @@
+name: "userfaultfd-sys"
+description: "Low-level bindings for userfaultfd functionality on Linux."
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/userfaultfd-sys"
+  }
+  url {
+    type: ARCHIVE
+    value: "https://static.crates.io/crates/userfaultfd-sys/userfaultfd-sys-0.4.2.crate"
+  }
+  version: "0.4.2"
+  # Dual-licensed, using the least restrictive per go/thirdpartylicenses#same.
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2022
+    month: 11
+    day: 16
+  }
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..3abd431
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1,5 @@
+include platform/prebuilts/rust:master:/OWNERS
+devinmoore@google.com
+fmayle@google.com
+khei@google.com
+smoreland@google.com
diff --git a/build.rs b/build.rs
new file mode 100644
index 0000000..af7cda6
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,74 @@
+use bindgen;
+use bindgen::callbacks::{IntKind, ParseCallbacks};
+use cc;
+use std::env;
+use std::path::PathBuf;
+
+fn main() {
+    generate_bindings();
+
+    cc::Build::new()
+        .file("src/consts.c")
+        .compile("userfaultfd_sys_consts");
+}
+
+fn generate_bindings() {
+    let mut bindings = bindgen::Builder::default()
+        .header("wrapper.h")
+        // filter out stuff from <linux/types.h>
+        .blocklist_item("__BITS_PER_LONG")
+        .blocklist_item("__FD_SETSIZE")
+        .blocklist_type("__[lb]e.*")
+        .blocklist_type("__w?sum.*")
+        .blocklist_type("__kernel_*")
+        .parse_callbacks(Box::new(Callbacks {}));
+
+    if let Ok(linux_headers) = std::env::var("LINUX_HEADERS") {
+        let mut incl_dir = PathBuf::from(&linux_headers);
+        incl_dir.push("include");
+        assert!(
+            incl_dir.exists(),
+            "LINUX_HEADERS env variable contains an include/ directory"
+        );
+        incl_dir.push("uapi");
+        assert!(
+            incl_dir.exists(),
+            "LINUX_HEADERS env variable contains an include/uapi/ directory"
+        );
+        bindings = bindings
+            .clang_arg(format!("-isystem{}/include", linux_headers))
+            .clang_arg(format!("-isystem{}/include/uapi", linux_headers));
+    }
+
+    let bindings = bindings.generate().expect("binding generation failed");
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("binding file couldn't be written");
+}
+
+// all this stuff with callbacks is to give the integer constants the right types
+
+#[derive(Debug)]
+struct Callbacks {}
+
+impl ParseCallbacks for Callbacks {
+    fn int_macro(&self, name: &str, _value: i64) -> Option<IntKind> {
+        for (prefix, kind) in [
+            ("_UFFDIO_", IntKind::U64),
+            ("UFFD_API", IntKind::U64),
+            ("UFFDIO", IntKind::U8),
+            ("UFFD_EVENT_", IntKind::U8),
+            ("UFFD_PAGEFAULT_FLAG_", IntKind::U64),
+            ("UFFD_FEATURE_", IntKind::U64),
+        ]
+        .iter()
+        {
+            if name.starts_with(prefix) {
+                return Some(*kind);
+            }
+        }
+        return None;
+    }
+}
diff --git a/src/consts.c b/src/consts.c
new file mode 100644
index 0000000..e19ca74
--- /dev/null
+++ b/src/consts.c
@@ -0,0 +1,71 @@
+#include <linux/types.h>
+#include <linux/ioctl.h>
+#include <linux/userfaultfd.h>
+
+#ifdef UFFD_API
+const __u64 _const_UFFD_API = UFFD_API;
+#endif
+
+#ifdef UFFD_API_FEATURES
+const __u64 _const_UFFD_API_FEATURES = UFFD_API_FEATURES;
+#endif
+
+#ifdef UFFD_API_IOCTLS
+const __u64 _const_UFFD_API_IOCTLS = UFFD_API_IOCTLS;
+#endif
+
+#ifdef UFFD_API_RANGE_IOCTLS
+const __u64 _const_UFFD_API_RANGE_IOCTLS = UFFD_API_RANGE_IOCTLS;
+#endif
+
+#ifdef UFFD_API_RANGE_IOCTLS_BASIC
+const __u64 _const_UFFD_API_RANGE_IOCTLS_BASIC = UFFD_API_RANGE_IOCTLS_BASIC;
+#endif
+
+#ifdef UFFDIO_REGISTER_MODE_MISSING
+const __u64 _const_UFFDIO_REGISTER_MODE_MISSING = UFFDIO_REGISTER_MODE_MISSING;
+#endif
+
+#ifdef UFFDIO_REGISTER_MODE_WP
+const __u64 _const_UFFDIO_REGISTER_MODE_WP = UFFDIO_REGISTER_MODE_WP;
+#endif
+
+#ifdef UFFDIO_COPY_MODE_DONTWAKE
+const __u64 _const_UFFDIO_COPY_MODE_DONTWAKE = UFFDIO_COPY_MODE_DONTWAKE;
+#endif
+
+#ifdef UFFDIO_COPY_MODE_WP
+const __u64 _const_UFFDIO_COPY_MODE_WP = UFFDIO_COPY_MODE_WP;
+#endif
+
+#ifdef UFFDIO_ZEROPAGE_MODE_DONTWAKE
+const __u64 _const_UFFDIO_ZEROPAGE_MODE_DONTWAKE = UFFDIO_ZEROPAGE_MODE_DONTWAKE;
+#endif
+
+#ifdef UFFDIO_API
+const __u32 _const_UFFDIO_API = UFFDIO_API;
+#endif
+
+#ifdef UFFDIO_REGISTER
+const __u32 _const_UFFDIO_REGISTER = UFFDIO_REGISTER;
+#endif
+
+#ifdef UFFDIO_UNREGISTER
+const __u32 _const_UFFDIO_UNREGISTER = UFFDIO_UNREGISTER;
+#endif
+
+#ifdef UFFDIO_WAKE
+const __u32 _const_UFFDIO_WAKE = UFFDIO_WAKE;
+#endif
+
+#ifdef UFFDIO_COPY
+const __u32 _const_UFFDIO_COPY = UFFDIO_COPY;
+#endif
+
+#ifdef UFFDIO_ZEROPAGE
+const __u32 _const_UFFDIO_ZEROPAGE = UFFDIO_ZEROPAGE;
+#endif
+
+#ifdef UFFDIO_WRITEPROTECT
+const __u32 _const_UFFDIO_WRITEPROTECT = UFFDIO_WRITEPROTECT;
+#endif
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..7164db2
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,26 @@
+//! System bindings to `userfaultfd`.
+//!
+//! The minimum supported Linux kernel version is 4.11, but additional features from 4.14+ are
+//! available by using the `linux4_14` Cargo feature.
+
+#![allow(non_upper_case_globals)]
+#![allow(non_camel_case_types)]
+#![allow(non_snake_case)]
+
+use cfg_if::cfg_if;
+
+cfg_if! {
+    if #[cfg(feature = "linux5_7")] {
+        mod linux5_7;
+        pub use crate::linux5_7::*;
+    }
+    else if #[cfg(feature = "linux4_14")] {
+        mod linux4_14;
+        pub use crate::linux4_14::*;
+    } else {
+        mod linux4_11;
+        pub use crate::linux4_11::*;
+    }
+}
+
+include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
diff --git a/src/linux4_11.rs b/src/linux4_11.rs
new file mode 100644
index 0000000..fab13a2
--- /dev/null
+++ b/src/linux4_11.rs
@@ -0,0 +1,105 @@
+use super::*;
+
+// The following are preprocessor constants that bindgen can't figure out, so we enter them manually
+// from <linux/userfaultfd.h>, and have tests to make sure they're accurate.
+
+pub const UFFD_API: u64 = 0xAA;
+pub const UFFD_API_FEATURES: u64 = UFFD_FEATURE_EVENT_FORK
+    | UFFD_FEATURE_EVENT_REMAP
+    | UFFD_FEATURE_EVENT_REMOVE
+    | UFFD_FEATURE_EVENT_UNMAP
+    | UFFD_FEATURE_MISSING_HUGETLBFS
+    | UFFD_FEATURE_MISSING_SHMEM;
+
+pub const UFFD_API_IOCTLS: u64 = 1 << _UFFDIO_REGISTER | 1 << _UFFDIO_UNREGISTER | 1 << _UFFDIO_API;
+pub const UFFD_API_RANGE_IOCTLS: u64 =
+    1 << _UFFDIO_WAKE | 1 << _UFFDIO_COPY | 1 << _UFFDIO_ZEROPAGE;
+
+pub const UFFDIO_REGISTER_MODE_MISSING: u64 = 1 << 0;
+pub const UFFDIO_REGISTER_MODE_WP: u64 = 1 << 1;
+
+pub const UFFDIO_COPY_MODE_DONTWAKE: u64 = 1 << 0;
+pub const UFFDIO_COPY_MODE_WP: u64 = 1 << 1;
+
+pub const UFFDIO_ZEROPAGE_MODE_DONTWAKE: u64 = 1 << 0;
+
+pub const UFFDIO_API: u32 = 0xc018aa3f;
+pub const UFFDIO_REGISTER: u32 = 0xc020aa00;
+pub const UFFDIO_UNREGISTER: u32 = 0x8010aa01;
+pub const UFFDIO_WAKE: u32 = 0x8010aa02;
+pub const UFFDIO_COPY: u32 = 0xc028aa03;
+pub const UFFDIO_ZEROPAGE: u32 = 0xc020aa04;
+pub const UFFDIO_WRITEPROTECT: u32 = 0xc018aa06;
+
+#[cfg(test)]
+mod const_tests {
+    use super::*;
+
+    extern "C" {
+        static _const_UFFD_API: u64;
+        static _const_UFFD_API_FEATURES: u64;
+        static _const_UFFD_API_IOCTLS: u64;
+        static _const_UFFD_API_RANGE_IOCTLS: u64;
+        static _const_UFFDIO_REGISTER_MODE_MISSING: u64;
+        static _const_UFFDIO_REGISTER_MODE_WP: u64;
+        static _const_UFFDIO_COPY_MODE_DONTWAKE: u64;
+        static _const_UFFDIO_COPY_MODE_WP: u64;
+        static _const_UFFDIO_ZEROPAGE_MODE_DONTWAKE: u64;
+        static _const_UFFDIO_API: u32;
+        static _const_UFFDIO_REGISTER: u32;
+        static _const_UFFDIO_UNREGISTER: u32;
+        static _const_UFFDIO_WAKE: u32;
+        static _const_UFFDIO_COPY: u32;
+        static _const_UFFDIO_ZEROPAGE: u32;
+        static _const_UFFDIO_WRITEPROTECT: u32;
+    }
+
+    #[test]
+    fn consts_correct() {
+        unsafe {
+            assert_eq!(UFFD_API, _const_UFFD_API, "UFFD_API");
+            assert_eq!(
+                UFFD_API_FEATURES, _const_UFFD_API_FEATURES,
+                "UFFD_API_FEATURES"
+            );
+            assert_eq!(UFFD_API_IOCTLS, _const_UFFD_API_IOCTLS, "UFFD_API_IOCTLS");
+            assert_eq!(
+                UFFD_API_RANGE_IOCTLS, _const_UFFD_API_RANGE_IOCTLS,
+                "UFFD_API_RANGE_IOCTLS"
+            );
+            assert_eq!(
+                UFFDIO_REGISTER_MODE_MISSING, _const_UFFDIO_REGISTER_MODE_MISSING,
+                "UFFDIO_REGISTER_MODE_MISSING"
+            );
+            assert_eq!(
+                UFFDIO_REGISTER_MODE_WP, _const_UFFDIO_REGISTER_MODE_WP,
+                "UFFDIO_REGISTER_MODE_WP"
+            );
+            assert_eq!(
+                UFFDIO_COPY_MODE_DONTWAKE, _const_UFFDIO_COPY_MODE_DONTWAKE,
+                "UFFDIO_COPY_MODE_DONTWAKE"
+            );
+            assert_eq!(
+                UFFDIO_COPY_MODE_WP, _const_UFFDIO_COPY_MODE_WP,
+                "UFFDIO_COPY_MODE_WP"
+            );
+            assert_eq!(
+                UFFDIO_ZEROPAGE_MODE_DONTWAKE, _const_UFFDIO_ZEROPAGE_MODE_DONTWAKE,
+                "UFFDIO_ZEROPAGE_MODE_DONTWAKE"
+            );
+            assert_eq!(UFFDIO_API, _const_UFFDIO_API, "UFFDIO_API");
+            assert_eq!(UFFDIO_REGISTER, _const_UFFDIO_REGISTER, "UFFDIO_REGISTER");
+            assert_eq!(
+                UFFDIO_UNREGISTER, _const_UFFDIO_UNREGISTER,
+                "UFFDIO_UNREGISTER"
+            );
+            assert_eq!(UFFDIO_WAKE, _const_UFFDIO_WAKE, "UFFDIO_WAKE");
+            assert_eq!(UFFDIO_COPY, _const_UFFDIO_COPY, "UFFDIO_COPY");
+            assert_eq!(UFFDIO_ZEROPAGE, _const_UFFDIO_ZEROPAGE, "UFFDIO_ZEROPAGE");
+            assert_eq!(
+                UFFDIO_WRITEPROTECT, _const_UFFDIO_WRITEPROTECT,
+                "UFFDIO_WRITEPROTECT"
+            );
+        }
+    }
+}
diff --git a/src/linux4_14.rs b/src/linux4_14.rs
new file mode 100644
index 0000000..d485171
--- /dev/null
+++ b/src/linux4_14.rs
@@ -0,0 +1,113 @@
+use super::*;
+
+// The following are preprocessor constants that bindgen can't figure out, so we enter them manually
+// from <linux/userfaultfd.h>, and have tests to make sure they're accurate.
+
+pub const UFFD_API: u64 = 0xAA;
+
+pub const UFFD_API_FEATURES: u64 = UFFD_FEATURE_EVENT_FORK
+    | UFFD_FEATURE_EVENT_REMAP
+    | UFFD_FEATURE_EVENT_REMOVE
+    | UFFD_FEATURE_EVENT_UNMAP
+    | UFFD_FEATURE_MISSING_HUGETLBFS
+    | UFFD_FEATURE_MISSING_SHMEM
+    | UFFD_FEATURE_SIGBUS
+    | UFFD_FEATURE_THREAD_ID;
+pub const UFFD_API_IOCTLS: u64 = 1 << _UFFDIO_REGISTER | 1 << _UFFDIO_UNREGISTER | 1 << _UFFDIO_API;
+pub const UFFD_API_RANGE_IOCTLS: u64 =
+    1 << _UFFDIO_WAKE | 1 << _UFFDIO_COPY | 1 << _UFFDIO_ZEROPAGE;
+pub const UFFD_API_RANGE_IOCTLS_BASIC: u64 = 1 << _UFFDIO_WAKE | 1 << _UFFDIO_COPY;
+
+pub const UFFDIO_REGISTER_MODE_MISSING: u64 = 1 << 0;
+pub const UFFDIO_REGISTER_MODE_WP: u64 = 1 << 1;
+
+pub const UFFDIO_COPY_MODE_DONTWAKE: u64 = 1 << 0;
+pub const UFFDIO_COPY_MODE_WP: u64 = 1 << 1;
+
+pub const UFFDIO_ZEROPAGE_MODE_DONTWAKE: u64 = 1 << 0;
+
+pub const UFFDIO_API: u32 = 0xc018aa3f;
+pub const UFFDIO_REGISTER: u32 = 0xc020aa00;
+pub const UFFDIO_UNREGISTER: u32 = 0x8010aa01;
+pub const UFFDIO_WAKE: u32 = 0x8010aa02;
+pub const UFFDIO_COPY: u32 = 0xc028aa03;
+pub const UFFDIO_ZEROPAGE: u32 = 0xc020aa04;
+pub const UFFDIO_WRITEPROTECT: u32 = 0xc018aa06;
+
+#[cfg(test)]
+mod const_tests {
+    use super::*;
+
+    extern "C" {
+        static _const_UFFD_API: u64;
+        static _const_UFFD_API_FEATURES: u64;
+        static _const_UFFD_API_IOCTLS: u64;
+        static _const_UFFD_API_RANGE_IOCTLS: u64;
+        static _const_UFFD_API_RANGE_IOCTLS_BASIC: u64;
+        static _const_UFFDIO_REGISTER_MODE_MISSING: u64;
+        static _const_UFFDIO_REGISTER_MODE_WP: u64;
+        static _const_UFFDIO_COPY_MODE_DONTWAKE: u64;
+        static _const_UFFDIO_COPY_MODE_WP: u64;
+        static _const_UFFDIO_ZEROPAGE_MODE_DONTWAKE: u64;
+        static _const_UFFDIO_API: u32;
+        static _const_UFFDIO_REGISTER: u32;
+        static _const_UFFDIO_UNREGISTER: u32;
+        static _const_UFFDIO_WAKE: u32;
+        static _const_UFFDIO_COPY: u32;
+        static _const_UFFDIO_ZEROPAGE: u32;
+        static _const_UFFDIO_WRITEPROTECT: u32;
+    }
+
+    #[test]
+    fn consts_correct() {
+        unsafe {
+            assert_eq!(UFFD_API, _const_UFFD_API, "UFFD_API");
+            assert_eq!(
+                UFFD_API_FEATURES, _const_UFFD_API_FEATURES,
+                "UFFD_API_FEATURES"
+            );
+            assert_eq!(UFFD_API_IOCTLS, _const_UFFD_API_IOCTLS, "UFFD_API_IOCTLS");
+            assert_eq!(
+                UFFD_API_RANGE_IOCTLS, _const_UFFD_API_RANGE_IOCTLS,
+                "UFFD_API_RANGE_IOCTLS"
+            );
+            assert_eq!(
+                UFFD_API_RANGE_IOCTLS_BASIC, _const_UFFD_API_RANGE_IOCTLS_BASIC,
+                "UFFD_API_RANGE_IOCTLS_BASIC"
+            );
+            assert_eq!(
+                UFFDIO_REGISTER_MODE_MISSING, _const_UFFDIO_REGISTER_MODE_MISSING,
+                "UFFDIO_REGISTER_MODE_MISSING"
+            );
+            assert_eq!(
+                UFFDIO_REGISTER_MODE_WP, _const_UFFDIO_REGISTER_MODE_WP,
+                "UFFDIO_REGISTER_MODE_WP"
+            );
+            assert_eq!(
+                UFFDIO_COPY_MODE_DONTWAKE, _const_UFFDIO_COPY_MODE_DONTWAKE,
+                "UFFDIO_COPY_MODE_DONTWAKE"
+            );
+            assert_eq!(
+                UFFDIO_COPY_MODE_WP, _const_UFFDIO_COPY_MODE_WP,
+                "UFFDIO_COPY_MODE_WP"
+            );
+            assert_eq!(
+                UFFDIO_ZEROPAGE_MODE_DONTWAKE, _const_UFFDIO_ZEROPAGE_MODE_DONTWAKE,
+                "UFFDIO_ZEROPAGE_MODE_DONTWAKE"
+            );
+            assert_eq!(UFFDIO_API, _const_UFFDIO_API, "UFFDIO_API");
+            assert_eq!(UFFDIO_REGISTER, _const_UFFDIO_REGISTER, "UFFDIO_REGISTER");
+            assert_eq!(
+                UFFDIO_UNREGISTER, _const_UFFDIO_UNREGISTER,
+                "UFFDIO_UNREGISTER"
+            );
+            assert_eq!(UFFDIO_WAKE, _const_UFFDIO_WAKE, "UFFDIO_WAKE");
+            assert_eq!(UFFDIO_COPY, _const_UFFDIO_COPY, "UFFDIO_COPY");
+            assert_eq!(UFFDIO_ZEROPAGE, _const_UFFDIO_ZEROPAGE, "UFFDIO_ZEROPAGE");
+            assert_eq!(
+                UFFDIO_WRITEPROTECT, _const_UFFDIO_WRITEPROTECT,
+                "UFFDIO_WRITEPROTECT"
+            );
+        }
+    }
+}
diff --git a/src/linux5_7.rs b/src/linux5_7.rs
new file mode 100644
index 0000000..05e43fc
--- /dev/null
+++ b/src/linux5_7.rs
@@ -0,0 +1,116 @@
+use super::*;
+
+// The following are preprocessor constants that bindgen can't figure out, so we enter them manually
+// from <linux/userfaultfd.h>, and have tests to make sure they're accurate.
+
+pub const UFFD_API: u64 = 0xAA;
+
+pub const UFFD_API_FEATURES: u64 = UFFD_FEATURE_PAGEFAULT_FLAG_WP
+    | UFFD_FEATURE_EVENT_FORK
+    | UFFD_FEATURE_EVENT_REMAP
+    | UFFD_FEATURE_EVENT_REMOVE
+    | UFFD_FEATURE_EVENT_UNMAP
+    | UFFD_FEATURE_MISSING_HUGETLBFS
+    | UFFD_FEATURE_MISSING_SHMEM
+    | UFFD_FEATURE_SIGBUS
+    | UFFD_FEATURE_THREAD_ID;
+pub const UFFD_API_IOCTLS: u64 = 1 << _UFFDIO_REGISTER | 1 << _UFFDIO_UNREGISTER | 1 << _UFFDIO_API;
+
+pub const UFFD_API_RANGE_IOCTLS: u64 =
+    1 << _UFFDIO_WAKE | 1 << _UFFDIO_COPY | 1 << _UFFDIO_ZEROPAGE | 1 << _UFFDIO_WRITEPROTECT;
+
+pub const UFFD_API_RANGE_IOCTLS_BASIC: u64 = 1 << _UFFDIO_WAKE | 1 << _UFFDIO_COPY;
+
+pub const UFFDIO_REGISTER_MODE_MISSING: u64 = 1 << 0;
+pub const UFFDIO_REGISTER_MODE_WP: u64 = 1 << 1;
+pub const UFFDIO_COPY_MODE_DONTWAKE: u64 = 1 << 0;
+pub const UFFDIO_COPY_MODE_WP: u64 = 1 << 1;
+pub const UFFDIO_ZEROPAGE_MODE_DONTWAKE: u64 = 1 << 0;
+pub const UFFDIO_WRITEPROTECT_MODE_WP: u64 = 1 << 0;
+pub const UFFDIO_WRITEPROTECT_MODE_DONTWAKE: u64 = 1 << 1;
+
+pub const UFFDIO_API: u32 = 0xc018aa3f;
+pub const UFFDIO_REGISTER: u32 = 0xc020aa00;
+pub const UFFDIO_UNREGISTER: u32 = 0x8010aa01;
+pub const UFFDIO_WAKE: u32 = 0x8010aa02;
+pub const UFFDIO_COPY: u32 = 0xc028aa03;
+pub const UFFDIO_ZEROPAGE: u32 = 0xc020aa04;
+pub const UFFDIO_WRITEPROTECT: u32 = 0xc018aa06;
+
+#[cfg(test)]
+mod const_tests {
+    use super::*;
+
+    extern "C" {
+        static _const_UFFD_API: u64;
+        static _const_UFFD_API_FEATURES: u64;
+        static _const_UFFD_API_IOCTLS: u64;
+        static _const_UFFD_API_RANGE_IOCTLS: u64;
+        static _const_UFFD_API_RANGE_IOCTLS_BASIC: u64;
+        static _const_UFFDIO_REGISTER_MODE_MISSING: u64;
+        static _const_UFFDIO_REGISTER_MODE_WP: u64;
+        static _const_UFFDIO_COPY_MODE_DONTWAKE: u64;
+        static _const_UFFDIO_COPY_MODE_WP: u64;
+        static _const_UFFDIO_ZEROPAGE_MODE_DONTWAKE: u64;
+        static _const_UFFDIO_API: u32;
+        static _const_UFFDIO_REGISTER: u32;
+        static _const_UFFDIO_UNREGISTER: u32;
+        static _const_UFFDIO_WAKE: u32;
+        static _const_UFFDIO_COPY: u32;
+        static _const_UFFDIO_ZEROPAGE: u32;
+        static _const_UFFDIO_WRITEPROTECT: u32;
+    }
+
+    #[test]
+    fn consts_correct() {
+        unsafe {
+            assert_eq!(UFFD_API, _const_UFFD_API, "UFFD_API");
+            assert_eq!(
+                UFFD_API_FEATURES, _const_UFFD_API_FEATURES,
+                "UFFD_API_FEATURES"
+            );
+            assert_eq!(UFFD_API_IOCTLS, _const_UFFD_API_IOCTLS, "UFFD_API_IOCTLS");
+            assert_eq!(
+                UFFD_API_RANGE_IOCTLS, _const_UFFD_API_RANGE_IOCTLS,
+                "UFFD_API_RANGE_IOCTLS"
+            );
+            assert_eq!(
+                UFFD_API_RANGE_IOCTLS_BASIC, _const_UFFD_API_RANGE_IOCTLS_BASIC,
+                "UFFD_API_RANGE_IOCTLS_BASIC"
+            );
+            assert_eq!(
+                UFFDIO_REGISTER_MODE_MISSING, _const_UFFDIO_REGISTER_MODE_MISSING,
+                "UFFDIO_REGISTER_MODE_MISSING"
+            );
+            assert_eq!(
+                UFFDIO_REGISTER_MODE_WP, _const_UFFDIO_REGISTER_MODE_WP,
+                "UFFDIO_REGISTER_MODE_WP"
+            );
+            assert_eq!(
+                UFFDIO_COPY_MODE_DONTWAKE, _const_UFFDIO_COPY_MODE_DONTWAKE,
+                "UFFDIO_COPY_MODE_DONTWAKE"
+            );
+            assert_eq!(
+                UFFDIO_COPY_MODE_WP, _const_UFFDIO_COPY_MODE_WP,
+                "UFFDIO_COPY_MODE_WP"
+            );
+            assert_eq!(
+                UFFDIO_ZEROPAGE_MODE_DONTWAKE, _const_UFFDIO_ZEROPAGE_MODE_DONTWAKE,
+                "UFFDIO_ZEROPAGE_MODE_DONTWAKE"
+            );
+            assert_eq!(UFFDIO_API, _const_UFFDIO_API, "UFFDIO_API");
+            assert_eq!(UFFDIO_REGISTER, _const_UFFDIO_REGISTER, "UFFDIO_REGISTER");
+            assert_eq!(
+                UFFDIO_UNREGISTER, _const_UFFDIO_UNREGISTER,
+                "UFFDIO_UNREGISTER"
+            );
+            assert_eq!(UFFDIO_WAKE, _const_UFFDIO_WAKE, "UFFDIO_WAKE");
+            assert_eq!(UFFDIO_COPY, _const_UFFDIO_COPY, "UFFDIO_COPY");
+            assert_eq!(UFFDIO_ZEROPAGE, _const_UFFDIO_ZEROPAGE, "UFFDIO_ZEROPAGE");
+            assert_eq!(
+                UFFDIO_WRITEPROTECT, _const_UFFDIO_WRITEPROTECT,
+                "UFFDIO_WRITEPROTECT"
+            );
+        }
+    }
+}
diff --git a/wrapper.h b/wrapper.h
new file mode 100644
index 0000000..42ab19c
--- /dev/null
+++ b/wrapper.h
@@ -0,0 +1,6 @@
+#include <linux/userfaultfd.h>
+#ifndef UFFD_USER_MODE_ONLY
+// this definition is not available before Linux 5.11. It is provided so
+// userfaultfd-sys has the same exports on all kernels
+#define UFFD_USER_MODE_ONLY 1
+#endif