[PATCH v5 1/2] rust: alloc: add from_raw method to Flags

[Vitaly Wool <vitaly.wool@konsulko.se>]

We need to be able to create Flags from its raw representation as u32
to properly map zpool C API into Rust. This patch adds from_raw method
to Flags and makes it crate private.

Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.se>
---
 rust/kernel/alloc.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/rust/kernel/alloc.rs b/rust/kernel/alloc.rs
index b39c279236f5..0c839813a15d 100644
--- a/rust/kernel/alloc.rs
+++ b/rust/kernel/alloc.rs
@@ -41,6 +41,13 @@
 pub struct Flags(u32);
 
 impl Flags {
+    /// Create `Flags` from the raw representation.
+    ///
+    /// `f` must be a valid combination of GFP flags.
+    pub(crate) fn from_raw(f: u32) -> Self {
+        Self(f)
+    }
+
     /// Get the raw representation of this flag.
     pub(crate) fn as_raw(self) -> u32 {
         self.0
-- 
2.39.2