Re: [PATCH net-next v9 1/4] rust: core abstractions for network PHY drivers
From: Boqun Feng <hidden>
Date: 2023-12-05 02:00:19
Also in:
rust-for-linux
On Tue, Dec 05, 2023 at 10:14:17AM +0900, FUJITA Tomonori wrote: [...]
+ /// Gets the current link state.
+ ///
+ /// It returns true if the link is up.
+ pub fn is_link_up(&self) -> bool {
+ const LINK_IS_UP: u64 = 1;
+ // TODO: the code to access to the bit field will be replaced with automatically
+ // generated code by bindgen when it becomes possible.
+ // SAFETY: The struct invariant ensures that we may access
+ // this field without additional synchronization.
+ let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
+ bit_field.get(14, 1) == LINK_IS_UP
I made a mistake here [1], this should be:
let bit_field = unsafe { &*(core::ptr::addr_of!((*self.0.get())._bitfield_1)) };
bit_field.get(14, 1) == LINK_IS_UP
without `core::ptr::add_of!`, `*(self.0.get())` would still create a
temporary `&` to the underlying object I believe. `addr_of!` is the way
to avoid create the temporary reference. Same for the other functions.
[1]: https://lore.kernel.org/rust-for-linux/ZT6fzfV9GUQOZnlx@boqun-archlinux/ (local)
Regards,
Boqun
+ }
+
+ /// Gets the current auto-negotiation configuration.
+ ///
+ /// It returns true if auto-negotiation is enabled.
+ pub fn is_autoneg_enabled(&self) -> bool {
+ // TODO: the code to access to the bit field will be replaced with automatically
+ // generated code by bindgen when it becomes possible.
+ // SAFETY: The struct invariant ensures that we may access
+ // this field without additional synchronization.
+ let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
+ bit_field.get(13, 1) == bindings::AUTONEG_ENABLE as u64
+ }
+
+ /// Gets the current auto-negotiation state.
+ ///
+ /// It returns true if auto-negotiation is completed.
+ pub fn is_autoneg_completed(&self) -> bool {
+ const AUTONEG_COMPLETED: u64 = 1;
+ // TODO: the code to access to the bit field will be replaced with automatically
+ // generated code by bindgen when it becomes possible.
+ // SAFETY: The struct invariant ensures that we may access
+ // this field without additional synchronization.
+ let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
+ bit_field.get(15, 1) == AUTONEG_COMPLETED
+ }
+[...]