| c1b4071e | 12-Apr-2025 |
FUJITA Tomonori <[email protected]> |
rust: helpers: Add dma_alloc_attrs() and dma_free_attrs()
Add dma_alloc_attrs() and dma_free_attrs() helpers to fix a build
error when CONFIG_HAS_DMA is not enabled.
Note that when CONFIG_HAS_DMA i
rust: helpers: Add dma_alloc_attrs() and dma_free_attrs()
Add dma_alloc_attrs() and dma_free_attrs() helpers to fix a build
error when CONFIG_HAS_DMA is not enabled.
Note that when CONFIG_HAS_DMA is enabled, dma_alloc_attrs() and
dma_free_attrs() are included in both bindings_generated.rs and
bindings_helpers_generated.rs. The former takes precedence so behavior
remains unchanged in that case.
This fixes the following build error on UML:
error[E0425]: cannot find function `dma_alloc_attrs` in crate `bindings`
--> rust/kernel/dma.rs:171:23
|
171 | bindings::dma_alloc_attrs(
| ^^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_alloc_pages`
|
::: rust/bindings/bindings_generated.rs:44568:5
|
44568 | / pub fn dma_alloc_pages(
44569 | | dev: *mut device,
44570 | | size: usize,
44571 | | dma_handle: *mut dma_addr_t,
44572 | | dir: dma_data_direction,
44573 | | gfp: gfp_t,
44574 | | ) -> *mut page;
| |___________________- similarly named function `dma_alloc_pages` defined here
error[E0425]: cannot find function `dma_free_attrs` in crate `bindings`
--> rust/kernel/dma.rs:293:23
|
293 | bindings::dma_free_attrs(
| ^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_free_pages`
|
::: rust/bindings/bindings_generated.rs:44577:5
|
44577 | / pub fn dma_free_pages(
44578 | | dev: *mut device,
44579 | | size: usize,
44580 | | page: *mut page,
44581 | | dma_handle: dma_addr_t,
44582 | | dir: dma_data_direction,
44583 | | );
| |______- similarly named function `dma_free_pages` defined here
Fixes: ad2907b4e308 ("rust: add dma coherent allocator abstraction")
Signed-off-by: FUJITA Tomonori <[email protected]>
Acked-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Reworded for relative paths. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>
show more ...
|
| 1bd8b6b2 | 19-Dec-2024 |
Danilo Krummrich <[email protected]> |
rust: pci: add basic PCI device / driver abstractions
Implement the basic PCI abstractions required to write a basic PCI
driver. This includes the following data structures:
The `pci::Driver` trait
rust: pci: add basic PCI device / driver abstractions
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 <[email protected]>
Signed-off-by: FUJITA Tomonori <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Tested-by: Dirk Behme <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
show more ...
|
| 76c01ded | 19-Dec-2024 |
Danilo Krummrich <[email protected]> |
rust: add devres abstraction
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
rust: add devres abstraction
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 <[email protected]>
Tested-by: Dirk Behme <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
show more ...
|
| ce30d94e | 19-Dec-2024 |
Danilo Krummrich <[email protected]> |
rust: add `io::{Io, IoRaw}` base types
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 spec
rust: add `io::{Io, IoRaw}` base types
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 <[email protected]>
Tested-by: Daniel Almeida <[email protected]>
Reviewed-by: Daniel Almeida <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Tested-by: Dirk Behme <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
show more ...
|
| 8362c260 | 04-Oct-2024 |
Danilo Krummrich <[email protected]> |
rust: alloc: implement `KVmalloc` allocator
Implement `Allocator` for `KVmalloc`, an `Allocator` that tries to
allocate memory with `kmalloc` first and, on failure, falls back to
`vmalloc`.
All mem
rust: alloc: implement `KVmalloc` allocator
Implement `Allocator` for `KVmalloc`, an `Allocator` that tries to
allocate memory with `kmalloc` first and, on failure, falls back to
`vmalloc`.
All memory allocations made with `KVmalloc` end up in
`kvrealloc_noprof()`; all frees in `kvfree()`.
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Reworded typo. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>
show more ...
|
| 61c00478 | 04-Oct-2024 |
Danilo Krummrich <[email protected]> |
rust: alloc: implement `Vmalloc` allocator
Implement `Allocator` for `Vmalloc`, the kernel's virtually contiguous
allocator, typically used for larger objects, (much) larger than page
size.
All mem
rust: alloc: implement `Vmalloc` allocator
Implement `Allocator` for `Vmalloc`, the kernel's virtually contiguous
allocator, typically used for larger objects, (much) larger than page
size.
All memory allocations made with `Vmalloc` end up in `vrealloc()`.
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>
show more ...
|
| e0020ba6 | 02-Oct-2024 |
Christian Brauner <[email protected]> |
rust: add PidNamespace
The lifetime of `PidNamespace` is bound to `Task` and `struct pid`.
The `PidNamespace` of a `Task` doesn't ever change once the `Task` is
alive. A `unshare(CLONE_NEWPID)` or
rust: add PidNamespace
The lifetime of `PidNamespace` is bound to `Task` and `struct pid`.
The `PidNamespace` of a `Task` doesn't ever change once the `Task` is
alive. A `unshare(CLONE_NEWPID)` or `setns(fd_pidns/pidfd, CLONE_NEWPID)`
will not have an effect on the calling `Task`'s pid namespace. It will
only effect the pid namespace of children created by the calling `Task`.
This invariant guarantees that after having acquired a reference to a
`Task`'s pid namespace it will remain unchanged.
When a task has exited and been reaped `release_task()` will be called.
This will set the `PidNamespace` of the task to `NULL`. So retrieving
the `PidNamespace` of a task that is dead will return `NULL`. Note, that
neither holding the RCU lock nor holding a referencing count to the
`Task` will prevent `release_task()` being called.
In order to retrieve the `PidNamespace` of a `Task` the
`task_active_pid_ns()` function can be used. There are two cases to
consider:
(1) retrieving the `PidNamespace` of the `current` task (2) retrieving
the `PidNamespace` of a non-`current` task
From system call context retrieving the `PidNamespace` for case (1) is
always safe and requires neither RCU locking nor a reference count to be
held. Retrieving the `PidNamespace` after `release_task()` for current
will return `NULL` but no codepath like that is exposed to Rust.
Retrieving the `PidNamespace` from system call context for (2) requires
RCU protection. Accessing `PidNamespace` outside of RCU protection
requires a reference count that must've been acquired while holding the
RCU lock. Note that accessing a non-`current` task means `NULL` can be
returned as the non-`current` task could have already passed through
`release_task()`.
To retrieve (1) the `current_pid_ns!()` macro should be used which
ensure that the returned `PidNamespace` cannot outlive the calling
scope. The associated `current_pid_ns()` function should not be called
directly as it could be abused to created an unbounded lifetime for
`PidNamespace`. The `current_pid_ns!()` macro allows Rust to handle the
common case of accessing `current`'s `PidNamespace` without RCU
protection and without having to acquire a reference count.
For (2) the `task_get_pid_ns()` method must be used. This will always
acquire a reference on `PidNamespace` and will return an `Option` to
force the caller to explicitly handle the case where `PidNamespace` is
`None`, something that tends to be forgotten when doing the equivalent
operation in `C`. Missing RCU primitives make it difficult to perform
operations that are otherwise safe without holding a reference count as
long as RCU protection is guaranteed. But it is not important currently.
But we do want it in the future.
Note for (2) the required RCU protection around calling
`task_active_pid_ns()` synchronizes against putting the last reference
of the associated `struct pid` of `task->thread_pid`. The `struct pid`
stored in that field is used to retrieve the `PidNamespace` of the
caller. When `release_task()` is called `task->thread_pid` will be
`NULL`ed and `put_pid()` on said `struct pid` will be delayed in
`free_pid()` via `call_rcu()` allowing everyone with an RCU protected
access to the `struct pid` acquired from `task->thread_pid` to finish.
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Alice Ryhl <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
show more ...
|
| 8ad1a41f | 15-Sep-2024 |
Alice Ryhl <[email protected]> |
rust: file: add `Kuid` wrapper
Adds a wrapper around `kuid_t` called `Kuid`. This allows us to define
various operations on kuids such as equality and current_euid. It also
lets us provide conversio
rust: file: add `Kuid` wrapper
Adds a wrapper around `kuid_t` called `Kuid`. This allows us to define
various operations on kuids such as equality and current_euid. It also
lets us provide conversions from kuid into userspace values.
Rust Binder needs these operations because it needs to compare kuids for
equality, and it needs to tell userspace about the pid and uid of
incoming transactions.
To read kuids from a `struct task_struct`, you must currently use
various #defines that perform the appropriate field access under an RCU
read lock. Currently, we do not have a Rust wrapper for rcu_read_lock,
which means that for this patch, there are two ways forward:
1. Inline the methods into Rust code, and use __rcu_read_lock directly
rather than the rcu_read_lock wrapper. This gives up lockdep for
these usages of RCU.
2. Wrap the various #defines in helpers and call the helpers from Rust.
This patch uses the second option. One possible disadvantage of the
second option is the possible introduction of speculation gadgets, but
as discussed in [1], the risk appears to be acceptable.
Of course, once a wrapper for rcu_read_lock is available, it is
preferable to use that over either of the two above approaches.
Link: https://lore.kernel.org/all/202312080947.674CD2DC7@keescook/ [1]
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Martin Rodriguez Reboredo <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Signed-off-by: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>
show more ...
|
| 94d356c0 | 15-Sep-2024 |
Alice Ryhl <[email protected]> |
rust: security: add abstraction for secctx
Add an abstraction for viewing the string representation of a security
context.
This is needed by Rust Binder because it has a feature where a process
can
rust: security: add abstraction for secctx
Add an abstraction for viewing the string representation of a security
context.
This is needed by Rust Binder because it has a feature where a process
can view the string representation of the security context for incoming
transactions. The process can use that to authenticate incoming
transactions, and since the feature is provided by the kernel, the
process can trust that the security context is legitimate.
This abstraction makes the following assumptions about the C side:
* When a call to `security_secid_to_secctx` is successful, it returns a
pointer and length. The pointer references a byte string and is valid
for reading for that many bytes.
* The string may be referenced until `security_release_secctx` is
called.
* If CONFIG_SECURITY is set, then the three methods mentioned in
rust/helpers are available without a helper. (That is, they are not a
#define or `static inline`.)
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Martin Rodriguez Reboredo <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Acked-by: Paul Moore <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
show more ...
|
| a3df991d | 15-Sep-2024 |
Wedson Almeida Filho <[email protected]> |
rust: cred: add Rust abstraction for `struct cred`
Add a wrapper around `struct cred` called `Credential`, and provide
functionality to get the `Credential` associated with a `File`.
Rust Binder mu
rust: cred: add Rust abstraction for `struct cred`
Add a wrapper around `struct cred` called `Credential`, and provide
functionality to get the `Credential` associated with a `File`.
Rust Binder must check the credentials of processes when they attempt to
perform various operations, and these checks usually take a
`&Credential` as parameter. The security_binder_set_context_mgr function
would be one example. This patch is necessary to access these security_*
methods from Rust.
This Rust abstraction makes the following assumptions about the C side:
* `struct cred` is refcounted with `get_cred`/`put_cred`.
* It's okay to transfer a `struct cred` across threads, that is, you do
not need to call `put_cred` on the same thread as where you called
`get_cred`.
* The `euid` field of a `struct cred` never changes after
initialization.
* The `f_cred` field of a `struct file` never changes after
initialization.
Signed-off-by: Wedson Almeida Filho <[email protected]>
Co-developed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Martin Rodriguez Reboredo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: Paul Moore <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
show more ...
|
| 85184982 | 15-Sep-2024 |
Wedson Almeida Filho <[email protected]> |
rust: file: add Rust abstraction for `struct file`
This abstraction makes it possible to manipulate the open files for a
process. The new `File` struct wraps the C `struct file`. When accessing
it u
rust: file: add Rust abstraction for `struct file`
This abstraction makes it possible to manipulate the open files for a
process. The new `File` struct wraps the C `struct file`. When accessing
it using the smart pointer `ARef<File>`, the pointer will own a
reference count to the file. When accessing it as `&File`, then the
reference does not own a refcount, but the borrow checker will ensure
that the reference count does not hit zero while the `&File` is live.
Since this is intended to manipulate the open files of a process, we
introduce an `fget` constructor that corresponds to the C `fget`
method. In future patches, it will become possible to create a new fd in
a process and bind it to a `File`. Rust Binder will use these to send
fds from one process to another.
We also provide a method for accessing the file's flags. Rust Binder
will use this to access the flags of the Binder fd to check whether the
non-blocking flag is set, which affects what the Binder ioctl does.
This introduces a struct for the EBADF error type, rather than just
using the Error type directly. This has two advantages:
* `File::fget` returns a `Result<ARef<File>, BadFdError>`, which the
compiler will represent as a single pointer, with null being an error.
This is possible because the compiler understands that `BadFdError`
has only one possible value, and it also understands that the
`ARef<File>` smart pointer is guaranteed non-null.
* Additionally, we promise to users of the method that the method can
only fail with EBADF, which means that they can rely on this promise
without having to inspect its implementation.
That said, there are also two disadvantages:
* Defining additional error types involves boilerplate.
* The question mark operator will only utilize the `From` trait once,
which prevents you from using the question mark operator on
`BadFdError` in methods that return some third error type that the
kernel `Error` is convertible into. (However, it works fine in methods
that return `Error`.)
Signed-off-by: Wedson Almeida Filho <[email protected]>
Co-developed-by: Daniel Xu <[email protected]>
Signed-off-by: Daniel Xu <[email protected]>
Co-developed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Signed-off-by: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
show more ...
|
| a0d13aac | 22-Aug-2024 |
Wedson Almeida Filho <[email protected]> |
rust: rbtree: add red-black tree implementation backed by the C version
The rust rbtree exposes a map-like interface over keys and values,
backed by the kernel red-black tree implementation. Values
rust: rbtree: add red-black tree implementation backed by the C version
The rust rbtree exposes a map-like interface over keys and values,
backed by the kernel red-black tree implementation. Values can be
inserted, deleted, and retrieved from a `RBTree` by key.
This base abstraction is used by binder to store key/value
pairs and perform lookups, for example the patch
"[PATCH RFC 03/20] rust_binder: add threading support"
in the binder RFC [1].
Link: https://lore.kernel.org/rust-for-linux/[email protected]/ [1]
Signed-off-by: Wedson Almeida Filho <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Alice Ryhl <[email protected]>
Reviewed-by: Boqun Feng <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Signed-off-by: Matt Gilbride <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Updated link to docs.kernel.org. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>
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|
| e26fa546 | 17-Aug-2024 |
Gary Guo <[email protected]> |
rust: kbuild: auto generate helper exports
This removes the need to explicitly export all symbols.
Generate helper exports similarly to what's currently done for Rust
crates. These helpers are excl
rust: kbuild: auto generate helper exports
This removes the need to explicitly export all symbols.
Generate helper exports similarly to what's currently done for Rust
crates. These helpers are exclusively called from within Rust code and
therefore can be treated similar as other Rust symbols.
Signed-off-by: Gary Guo <[email protected]>
Reviewed-by: Boqun Feng <[email protected]>
Tested-by: Boqun Feng <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Fixed dependency path, reworded slightly, edited comment a bit and
rebased on top of the changes made when applying Andreas' patch
(e.g. no `README.md` anymore, so moved the edits). - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>
show more ...
|