linux/rust
Danilo Krummrich f301cb978c rust: devres: implement Devres::access()
Implement a direct accessor for the data stored within the Devres for
cases where we can prove that we own a reference to a Device<Bound>
(i.e. a bound device) of the same device that was used to create the
corresponding Devres container.

Usually, when accessing the data stored within a Devres container, it is
not clear whether the data has been revoked already due to the device
being unbound and, hence, we have to try whether the access is possible
and subsequently keep holding the RCU read lock for the duration of the
access.

However, when we can prove that we hold a reference to Device<Bound>
matching the device the Devres container has been created with, we can
guarantee that the device is not unbound for the duration of the
lifetime of the Device<Bound> reference and, hence, it is not possible
for the data within the Devres container to be revoked.

Therefore, in this case, we can bypass the atomic check and the RCU read
lock, which is a great optimization and simplification for drivers.

Reviewed-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Link: https://lore.kernel.org/r/20250428140137.468709-3-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-05-04 17:54:04 +02:00
..
bindings rust: drm: gem: Add GEM object abstraction 2025-04-28 10:08:23 +02:00
helpers rust: drm: gem: Add GEM object abstraction 2025-04-28 10:08:23 +02:00
kernel rust: devres: implement Devres::access() 2025-05-04 17:54:04 +02:00
macros Rust changes for v6.15 2025-03-30 17:03:26 -07:00
pin-init Rust changes for v6.15 2025-03-30 17:03:26 -07:00
uapi rust: drm: ioctl: Add DRM ioctl abstraction 2025-04-24 13:50:05 +02:00
.gitignore rust: support running Rust documentation tests as KUnit ones 2023-07-19 09:32:53 -06:00
.kunitconfig rust: add kunitconfig 2025-03-19 23:22:21 +01:00
bindgen_parameters rust: map __kernel_size_t and friends also to usize/isize 2024-11-10 23:58:00 +01:00
build_error.rs rust: add build_error crate 2022-12-04 01:59:16 +01:00
compiler_builtins.rs ARM: 9441/1: rust: Enable Rust support for ARMv7 2025-03-26 13:31:16 +00:00
exports.c rust: exports: improve grammar in commentary 2024-10-21 17:35:33 +02:00
ffi.rs rust: map long to isize and char to u8 2024-12-16 21:49:33 +01:00
Makefile Kbuild updates for v6.15 2025-04-05 15:46:50 -07:00