The sibling `build_assert!` is already in the prelude, it makes sense
that a "core"/"language" facility like this is part of the prelude and
users should not be defining their own one (thus there should be no risk
of future name collisions and we would want to be aware of them anyway).
Thus add `build_error!` into the prelude.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20241123222849.350287-3-ojeda@kernel.org
[ Applied the change to the new miscdevice cases. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Users were using the hidden exported `kernel::build_error` function
instead of the intended `kernel::build_error!` macro, e.g. see the
previous commit.
To force to use the macro, move it into the `build_assert` module,
thus making it a compilation error and avoiding a collision in the same
"namespace". Using the function now would require typing the module name
(which is hidden), not just a single character.
Now attempting to use the function will trigger this error with the
right suggestion by the compiler:
error[E0423]: expected function, found macro `kernel::build_error`
--> samples/rust/rust_minimal.rs:29:9
|
29 | kernel::build_error();
| ^^^^^^^^^^^^^^^^^^^ not a function
|
help: use `!` to invoke the macro
|
29 | kernel::build_error!();
| +
An alternative would be using an alias, but it would be more complex
and moving it into the module seems right since it belongs there and
reduces the amount of code at the crate root.
Keep the `#[doc(hidden)]` inside `build_assert` in case the module is
not hidden in the future.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20241123222849.350287-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Running Clippy for `rusttest` code is useful to catch issues there too,
even if the code is not as critical. In the future, this code may also
run in kernelspace and could be copy-pasted. Thus it is useful to keep
it under the same standards. For instance, it will now make us add
`// SAFETY` comments.
It also makes everything more consistent.
Thus clean the few issues spotted by Clippy and start running it.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20241123180639.260191-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Pull workqueue fixes from Tejun Heo:
- Suppress a corner case spurious flush dependency warning
- Two trivial changes
* tag 'wq-for-6.13-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: add printf attribute to __alloc_workqueue()
workqueue: Do not warn when cancelling WQ_MEM_RECLAIM work from !WQ_MEM_RECLAIM worker
rust: add safety comment in workqueue traits
Implement the basic platform bus abstractions required to write a basic
platform driver. This includes the following data structures:
The `platform::Driver` trait represents the interface to the driver and
provides `platform::Driver::probe` for the driver to implement.
The `platform::Device` abstraction represents a `struct platform_device`.
In order to provide the platform bus specific parts to a generic
`driver::Registration` the `driver::RegistrationOps` trait is implemented
by `platform::Adapter`.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-15-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to not duplicate code in bus specific implementations (e.g.
platform), implement a generic `driver::Adapter` to represent the
connection of matched drivers and devices.
Bus specific `Adapter` implementations can simply implement this trait
to inherit generic functionality, such as matching OF or ACPI device IDs
and ID table entries.
Suggested-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-14-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement `pci::Bar`, `pci::Device::iomap_region` and
`pci::Device::iomap_region_sized` to allow for I/O mappings of PCI BARs.
To ensure that a `pci::Bar`, and hence the I/O memory mapping, can't
out-live the PCI device, the `pci::Bar` type is always embedded into a
`Devres` container, such that the `pci::Bar` is revoked once the device
is unbound and hence the I/O mapped memory is unmapped.
A `pci::Bar` can be requested with (`pci::Device::iomap_region_sized`) or
without (`pci::Device::iomap_region`) a const generic representing the
minimal requested size of the I/O mapped memory region. In case of the
latter only runtime checked I/O reads / writes are possible.
Co-developed-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-11-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement the basic PCI abstractions required to write a basic PCI
driver. This includes the following data structures:
The `pci::Driver` trait represents the interface to the driver and
provides `pci::Driver::probe` for the driver to implement.
The `pci::Device` abstraction represents a `struct pci_dev` and provides
abstractions for common functions, such as `pci::Device::set_master`.
In order to provide the PCI specific parts to a generic
`driver::Registration` the `driver::RegistrationOps` trait is implemented
by `pci::Adapter`.
`pci::DeviceId` implements PCI device IDs based on the generic
`device_id::RawDevceId` abstraction.
Co-developed-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-10-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a Rust abstraction for the kernel's devres (device resource
management) implementation.
The Devres type acts as a container to manage the lifetime and
accessibility of device bound resources. Therefore it registers a
devres callback and revokes access to the resource on invocation.
Users of the Devres abstraction can simply free the corresponding
resources in their Drop implementation, which is invoked when either the
Devres instance goes out of scope or the devres callback leads to the
resource being revoked, which implies a call to drop_in_place().
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-9-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I/O memory is typically either mapped through direct calls to ioremap()
or subsystem / bus specific ones such as pci_iomap().
Even though subsystem / bus specific functions to map I/O memory are
based on ioremap() / iounmap() it is not desirable to re-implement them
in Rust.
Instead, implement a base type for I/O mapped memory, which generically
provides the corresponding accessors, such as `Io::readb` or
`Io:try_readb`.
`Io` supports an optional const generic, such that a driver can indicate
the minimal expected and required size of the mapping at compile time.
Correspondingly, calls to the 'non-try' accessors, support compile time
checks of the I/O memory offset to read / write, while the 'try'
accessors, provide boundary checks on runtime.
`IoRaw` is meant to be embedded into a structure (e.g. pci::Bar or
io::IoMem) which creates the actual I/O memory mapping and initializes
`IoRaw` accordingly.
To ensure that I/O mapped memory can't out-live the device it may be
bound to, subsystems must embed the corresponding I/O memory type (e.g.
pci::Bar) into a `Devres` container, such that it gets revoked once the
device is unbound.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-8-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revocable allows access to objects to be safely revoked at run time.
This is useful, for example, for resources allocated during device probe;
when the device is removed, the driver should stop accessing the device
resources even if another state is kept in memory due to existing
references (i.e., device context data is ref-counted and has a non-zero
refcount after removal of the device).
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Link: https://lore.kernel.org/r/20241219170425.12036-7-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement the generic `Registration` type and the `RegistrationOps`
trait.
The `Registration` structure is the common type that represents a driver
registration and is typically bound to the lifetime of a module. However,
it doesn't implement actual calls to the kernel's driver core to register
drivers itself.
Instead the `RegistrationOps` trait is provided to subsystems, which have
to implement `RegistrationOps::register` and
`RegistrationOps::unregister`. Subsystems have to provide an
implementation for both of those methods where the subsystem specific
variants to register / unregister a driver have to implemented.
For instance, the PCI subsystem would call __pci_register_driver() from
`RegistrationOps::register` and pci_unregister_driver() from
`DrvierOps::unregister`.
Co-developed-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Tested-by: Fabien Parent <fabien.parent@linaro.org>
Link: https://lore.kernel.org/r/20241219170425.12036-3-dakr@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since we've exposed Lock::from_raw() and Guard::new() publically, we
want to be able to make sure that we assert that a lock is actually held
when constructing a Guard for it to handle instances of unsafe
Guard::new() calls outside of our lock module.
Hence add a new method assert_is_held() to Backend, which uses lockdep
to check whether or not a lock has been acquired. When lockdep is
disabled, this has no overhead.
[Boqun: Resolve the conflicts with exposing Guard::new(), reword the
commit log a bit and format "unsafe { <statement>; }" into "unsafe {
<statement> }" for the consistency. ]
Signed-off-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20241125204139.656801-1-lyude@redhat.com
Since we added a `Lock::from_raw()` function previously, it makes sense
to also introduce an interface for creating a `Guard` from a reference
to a `Lock` for instances where we've derived the `Lock` from a raw
pointer and know that the lock is already acquired, there are such
usages in KMS API.
[Boqun: Add backquotes to type names, reformat the commit log, reword a
bit on the usage of KMS API]
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Filipe Xavier <felipe_life@live.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20241119231146.2298971-3-lyude@redhat.com
The KMS bindings [1] have a few bindings that require manually acquiring
specific locks before calling certain functions. At the moment though,
the only way of acquiring these locks in bindings is to simply call the
C locking functions directly - since said locks are not initialized on
the Rust side of things.
However - if we add `#[repr(C)]` to `Lock<(), B>`, then given `()` is a
ZST - `Lock<(), B>` becomes equivalent in data layout to its inner
`B::State` type. Since locks in C don't have data explicitly associated
with them anyway, we can take advantage of this to add a
`Lock::from_raw()` function that can translate a raw pointer to
`B::State` into its proper `Lock<(), B>` equivalent. This lets us simply
acquire a reference to the lock in question and work with it like it was
initialized on the Rust side of things, allowing us to use less unsafe
code to implement bindings with lock requirements.
[Boqun: Use "Link:" instead of a URL and format the commit log]
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patchwork.freedesktop.org/series/131522/ [1]
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20241119231146.2298971-2-lyude@redhat.com
Having the Rust doctests enabled these workqueue tests are built but not
executed as the final callers of the print_*() functions are missing.
Add them.
The result is
# rust_doctest_kernel_workqueue_rs_0.location: rust/kernel/workqueue.rs:35
rust_doctests_kernel: The value is: 42
ok 94 rust_doctest_kernel_workqueue_rs_0
# rust_doctest_kernel_workqueue_rs_3.location: rust/kernel/workqueue.rs:78
rust_doctests_kernel: The value is: 24
rust_doctests_kernel: The second value is: 42
ok 97 rust_doctest_kernel_workqueue_rs_3
Without this change the "The value ..." outputs are not there meaning
that this test code is not run.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/cb953202-0dbe-4127-8a8e-6a75258c2116@gmail.com
[ Reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
With `long` mapped to `isize`, `size_t`/`__kernel_size_t` mapped to
`usize` and `char` mapped to `u8`, many of the existing casts are no
longer necessary.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240913213041.395655-6-gary@garyguo.net
[ Moved `uaccess` changes to the previous commit, since they were
irrefutable patterns that Rust >= 1.82.0 warns about. Removed a
couple casts that now use `c""` literals. Rebased on top of
`rust-next`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The following FFI types are replaced compared to `core::ffi`:
1. `char` type is now always mapped to `u8`, since kernel uses
`-funsigned-char` on the C code. `core::ffi` maps it to platform
default ABI, which can be either signed or unsigned.
2. `long` is now always mapped to `isize`. It's very common in the
kernel to use `long` to represent a pointer-sized integer, and in
fact `intptr_t` is a typedef of `long` in the kernel. Enforce this
mapping rather than mapping to `i32/i64` depending on platform can
save us a lot of unnecessary casts.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240913213041.395655-5-gary@garyguo.net
[ Moved `uaccess` changes from the next commit, since they were
irrefutable patterns that Rust >= 1.82.0 warns about. Reworded
slightly and reformatted a few documentation comments. Rebased on
top of `rust-next`. Added the removal of two casts to avoid Clippy
warnings. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Providing access to the underlying `struct miscdevice` is useful for
various reasons. For example, this allows you access the miscdevice's
internal `struct device` for use with the `dev_*` printing macros.
Note that since the underlying `struct miscdevice` could get freed at
any point after the fops->open() call (if misc_deregister is called),
only the open call is given access to it. To use `dev_*` printing macros
from other fops hooks, take a refcount on `miscdevice->this_device` to
keep it alive. See the linked thread for further discussion on the
lifetime of `struct miscdevice`.
Link: https://lore.kernel.org/r/2024120951-botanist-exhale-4845@gregkh
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Lee Jones <lee@kernel.org>
Tested-by: Lee Jones <lee@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241210-miscdevice-file-param-v3-2-b2a79b666dc5@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull more block updates from Jens Axboe:
- NVMe pull request via Keith:
- Use correct srcu list traversal (Breno)
- Scatter-gather support for metadata (Keith)
- Fabrics shutdown race condition fix (Nilay)
- Persistent reservations updates (Guixin)
- Add the required bits for MD atomic write support for raid0/1/10
- Correct return value for unknown opcode in ublk
- Fix deadlock with zone revalidation
- Fix for the io priority request vs bio cleanups
- Use the correct unsigned int type for various limit helpers
- Fix for a race in loop
- Cleanup blk_rq_prep_clone() to prevent uninit-value warning and make
it easier for actual humans to read
- Fix potential UAF when iterating tags
- A few fixes for bfq-iosched UAF issues
- Fix for brd discard not decrementing the allocated page count
- Various little fixes and cleanups
* tag 'block-6.13-20242901' of git://git.kernel.dk/linux: (36 commits)
brd: decrease the number of allocated pages which discarded
block, bfq: fix bfqq uaf in bfq_limit_depth()
block: Don't allow an atomic write be truncated in blkdev_write_iter()
mq-deadline: don't call req_get_ioprio from the I/O completion handler
block: Prevent potential deadlock in blk_revalidate_disk_zones()
block: Remove extra part pointer NULLify in blk_rq_init()
nvme: tuning pr code by using defined structs and macros
nvme: introduce change ptpl and iekey definition
block: return bool from get_disk_ro and bdev_read_only
block: remove a duplicate definition for bdev_read_only
block: return bool from blk_rq_aligned
block: return unsigned int from blk_lim_dma_alignment_and_pad
block: return unsigned int from queue_dma_alignment
block: return unsigned int from bdev_io_opt
block: req->bio is always set in the merge code
block: don't bother checking the data direction for merges
block: blk-mq: fix uninit-value in blk_rq_prep_clone and refactor
Revert "block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator()"
md/raid10: Atomic write support
md/raid1: Atomic write support
...
Pull char/misc/IIO/whatever driver subsystem updates from Greg KH:
"Here is the 'big and hairy' char/misc/iio and other small driver
subsystem updates for 6.13-rc1.
Loads of things in here, and even a fun merge conflict!
- rust misc driver bindings and other rust changes to make misc
drivers actually possible.
I think this is the tipping point, expect to see way more rust
drivers going forward now that these bindings are present. Next
merge window hopefully we will have pci and platform drivers
working, which will fully enable almost all driver subsystems to
start accepting (or at least getting) rust drivers.
This is the end result of a lot of work from a lot of people,
congrats to all of them for getting this far, you've proved many of
us wrong in the best way possible, working code :)
- IIO driver updates, too many to list individually, that subsystem
keeps growing and growing...
- Interconnect driver updates
- nvmem driver updates
- pwm driver updates
- platform_driver::remove() fixups, loads of them
- counter driver updates
- misc driver updates (keba?)
- binder driver updates and fixes
- loads of other small char/misc/etc driver updates and additions,
full details in the shortlog.
All of these have been in linux-next for a while, with no other
reported issues other than that merge conflict"
* tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (401 commits)
mei: vsc: Fix typo "maintstepping" -> "mainstepping"
firmware: Switch back to struct platform_driver::remove()
misc: isl29020: Fix the wrong format specifier
scripts/tags.sh: Don't tag usages of DEFINE_MUTEX
fpga: Switch back to struct platform_driver::remove()
mei: vsc: Improve error logging in vsc_identify_silicon()
mei: vsc: Do not re-enable interrupt from vsc_tp_reset()
dt-bindings: spmi: qcom,x1e80100-spmi-pmic-arb: Add SAR2130P compatible
dt-bindings: spmi: spmi-mtk-pmif: Add compatible for MT8188
spmi: pmic-arb: fix return path in for_each_available_child_of_node()
iio: Move __private marking before struct element priv in struct iio_dev
docs: iio: ad7380: add adaq4370-4 and adaq4380-4
iio: adc: ad7380: add support for adaq4370-4 and adaq4380-4
iio: adc: ad7380: use local dev variable to shorten long lines
iio: adc: ad7380: fix oversampling formula
dt-bindings: iio: adc: ad7380: add adaq4370-4 and adaq4380-4 compatible parts
bus: mhi: host: pci_generic: Use pcim_iomap_region() to request and map MHI BAR
bus: mhi: host: Switch trace_mhi_gen_tre fields to native endian
misc: atmel-ssc: Use of_property_present() for non-boolean properties
misc: keba: Add hardware dependency
...
When I merged the rust 'use' imports, I didn't realize that there's
an offical preferred idiomatic format - so while it all worked fine,
it doesn't match what 'make rustfmt' wants to make it.
Fix it up appropriately.
Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alice Ryhl