sys::memfd additional flags related to the hugetlb filesystem support.

nix-rust · Dec 6, 2023 · c366102 · c366102
1 parent da45140
commit c366102
Show file tree

Hide file tree

Showing 2 changed files with 44 additions and 0 deletions.
diff --git a/changelog/2252.added.md b/changelog/2252.added.md
@@ -0,0 +1 @@
+Added new `MemFdCreateFlag` constants to `sys::memfd` on Linux and Android related to hugetlbfs support.
diff --git a/src/sys/memfd.rs b/src/sys/memfd.rs
@@ -29,6 +29,49 @@ libc_bitflags!(
         ///
         /// [`memfd_create(2)`]: https://man7.org/linux/man-pages/man2/memfd_create.2.html
         MFD_ALLOW_SEALING;
+        /// Anonymous file will be created using huge pages. It should be safe now to
+        /// combine with [`MFD_ALLOW_SEALING`] too.
+        /// However, despite its presence, on FreeBSD it is unimplemented for now (ENOSYS).
+        ///
+        /// See also the hugetlb filesystem in [`memfd_create(2)`].
+        ///
+        /// [`memfd_create(2)`]: https://man7.org/linux/man-pages/man2/memfd_create.2.html
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGETLB;
+        /// Following are to be used with [`MFD_HUGETLB`], indicating the desired hugetlb size.
+        ///
+        /// See also the hugetlb filesystem in [`memfd_create(2)`].
+        ///
+        /// [`memfd_create(2)`]: https://man7.org/linux/man-pages/man2/memfd_create.2.html
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_1MB;
+        /// hugetlb size of 2MB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_2MB;
+        /// hugetlb size of 8MB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_8MB;
+        /// hugetlb size of 16MB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_16MB;
+        /// hugetlb size of 32MB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_32MB;
+        /// hugetlb size of 256MB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_256MB;
+        /// hugetlb size of 512MB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_512MB;
+        /// hugetlb size of 1GB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_1GB;
+        /// hugetlb size of 2GB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_2GB;
+        /// hugetlb size of 16GB.
+        #[cfg(any(target_os = "linux", target_os = "android"))]
+        MFD_HUGE_16GB;
     }
 );