From: Danilo Krummrich <dakr@kernel.org>
Date: Fri, 4 Oct 2024 15:41:28 +0000 (+0200)
Subject: rust: alloc: implement `contains` for `Flags`
X-Git-Tag: v6.13-rc1~71^2~31
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=909037ce0369bc3f4fd31743fd2d8d7096f06002;p=thirdparty%2Flinux.git

rust: alloc: implement `contains` for `Flags`

Provide a simple helper function to check whether given flags do
contain one or multiple other flags.

This is used by a subsequent patch implementing the Cmalloc `Allocator`
to check for __GFP_ZERO.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-25-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---

diff --git a/rust/kernel/alloc.rs b/rust/kernel/alloc.rs
index 7fc2e404e594d..049fca7a514d1 100644
--- a/rust/kernel/alloc.rs
+++ b/rust/kernel/alloc.rs
@@ -35,7 +35,7 @@ use core::{alloc::Layout, ptr::NonNull};
 /// They can be combined with the operators `|`, `&`, and `!`.
 ///
 /// Values can be used from the [`flags`] module.
-#[derive(Clone, Copy)]
+#[derive(Clone, Copy, PartialEq)]
 pub struct Flags(u32);
 
 impl Flags {
@@ -43,6 +43,11 @@ impl Flags {
     pub(crate) fn as_raw(self) -> u32 {
         self.0
     }
+
+    /// Check whether `flags` is contained in `self`.
+    pub fn contains(self, flags: Flags) -> bool {
+        (self & flags) == flags
+    }
 }
 
 impl core::ops::BitOr for Flags {