`MIN_SIZE` and `io_addr_assert` are only ever used for IO types which
implement `IoKnownSize` and do not make sense for types that don't.
It looks like they should have been there since the beginning, so move
them while the code is still fresh.
Also update `IoKnownSize`'s documentation since it is not just a marker
trait anymore.
Fixes: 121d87b28e ("rust: io: separate generic I/O helpers from MMIO implementation")
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Link: https://patch.msgid.link/20260130-io-min-size-v1-1-65a546e3104d@nvidia.com
[ Fix typo in commit message. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Drivers might need to access PCI config space for querying capability
structures and access the registers inside the structures.
For Rust drivers need to access PCI config space, the Rust PCI abstraction
needs to support it in a way that upholds Rust's safety principles.
Introduce a `ConfigSpace` wrapper in Rust PCI abstraction to provide safe
accessors for PCI config space. The new type implements the `Io` trait and
`IoCapable<T>` for u8, u16, and u32 to share offset validation and
bound-checking logic with other I/O backends.
The `ConfigSpace` type uses marker types (`Normal` and `Extended`) to
represent configuration space sizes at the type level.
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Zhi Wang <zhiw@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/all/DFV4IJDQC2J6.1Q91JOAL6CJSG@kernel.org/ [1]
Link: https://patch.msgid.link/20260121202212.4438-5-zhiw@nvidia.com
[ Applied the diff from [1], considering subsequent comment; remove
#[expect(unused)] from define_{read,write}!(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
The previous Io<SIZE> type combined both the generic I/O access helpers
and MMIO implementation details in a single struct. This coupling prevented
reusing the I/O helpers for other backends, such as PCI configuration
space.
Establish a clean separation between the I/O interface and concrete
backends by separating generic I/O helpers from MMIO implementation.
Introduce a new trait hierarchy to handle different access capabilities:
- IoCapable<T>: A marker trait indicating that a backend supports I/O
operations of a certain type (u8, u16, u32, or u64).
- Io trait: Defines fallible (try_read8, try_write8, etc.) and infallibile
(read8, write8, etc.) I/O methods with runtime bounds checking and
compile-time bounds checking.
- IoKnownSize trait: The marker trait for types support infallible I/O
methods.
Move the MMIO-specific logic into a dedicated Mmio<SIZE> type that
implements the Io traits. Rename IoRaw to MmioRaw and update consumers to
use the new types.
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Zhi Wang <zhiw@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260121202212.4438-3-zhiw@nvidia.com
[ Add #[expect(unused)] to define_{read,write}!(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
