| 7a718a1f | 19-Dec-2024 |
Danilo Krummrich <[email protected]> |
rust: driver: implement `Adapter`
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
rust: driver: implement `Adapter`
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) <[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 ...
|
| ad37bcd9 | 30-Oct-2024 |
Alice Ryhl <[email protected]> |
rust: add tracepoint support
Make it possible to have Rust code call into tracepoints defined by C code. It is still required that the tracepoint is declared in a C header, and that this header is i
rust: add tracepoint support
Make it possible to have Rust code call into tracepoints defined by C code. It is still required that the tracepoint is declared in a C header, and that this header is included in the input to bindgen.
Instead of calling __DO_TRACE directly, the exported rust_do_trace_ function calls an inline helper function. This is because the `cond` argument does not exist at the callsite of DEFINE_RUST_DO_TRACE.
__DECLARE_TRACE always emits an inline static and an extern declaration that is only used when CREATE_RUST_TRACE_POINTS is set. These should not end up in the final binary so it is not a problem that they sometimes are emitted without a user.
Cc: Masami Hiramatsu <[email protected]> Cc: Mathieu Desnoyers <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Jason Baron <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Miguel Ojeda <[email protected]> Cc: Alex Gaynor <[email protected]> Cc: Wedson Almeida Filho <[email protected]> Cc: " =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= " <[email protected]> Cc: Benno Lossin <[email protected]> Cc: Andreas Hindborg <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Sean Christopherson <[email protected]> Cc: Uros Bizjak <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Oliver Upton <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Ryan Roberts <[email protected]> Cc: Fuad Tabba <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Albert Ou <[email protected]> Cc: Anup Patel <[email protected]> Cc: Andrew Jones <[email protected]> Cc: Alexandre Ghiti <[email protected]> Cc: Conor Dooley <[email protected]> Cc: Samuel Holland <[email protected]> Cc: Huacai Chen <[email protected]> Cc: WANG Xuerui <[email protected]> Cc: Bibo Mao <[email protected]> Cc: Tiezhu Yang <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Tianrui Zhao <[email protected]> Link: https://lore.kernel.org/[email protected] Reviewed-by: Carlos Llamas <[email protected]> Reviewed-by: Gary Guo <[email protected]> Reviewed-by: Boqun Feng <[email protected]> Signed-off-by: Alice Ryhl <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
show more ...
|
| ac681835 | 15-Sep-2024 |
Alice Ryhl <[email protected]> |
rust: file: add abstraction for `poll_table`
The existing `CondVar` abstraction is a wrapper around `wait_queue_head`, but it does not support all use-cases of the C `wait_queue_head` type. To be sp
rust: file: add abstraction for `poll_table`
The existing `CondVar` abstraction is a wrapper around `wait_queue_head`, but it does not support all use-cases of the C `wait_queue_head` type. To be specific, a `CondVar` cannot be registered with a `struct poll_table`. This limitation has the advantage that you do not need to call `synchronize_rcu` when destroying a `CondVar`.
However, we need the ability to register a `poll_table` with a `wait_queue_head` in Rust Binder. To enable this, introduce a type called `PollCondVar`, which is like `CondVar` except that you can register a `poll_table`. We also introduce `PollTable`, which is a safe wrapper around `poll_table` that is intended to be used with `PollCondVar`.
The destructor of `PollCondVar` unconditionally calls `synchronize_rcu` to ensure that the removal of epoll waiters has fully completed before the `wait_queue_head` is destroyed.
That said, `synchronize_rcu` is rather expensive and is not needed in all cases: If we have never registered a `poll_table` with the `wait_queue_head`, then we don't need to call `synchronize_rcu`. (And this is a common case in Binder - not all processes use Binder with epoll.) The current implementation does not account for this, but if we find that it is necessary to improve this, a future patch could store a boolean next to the `wait_queue_head` to keep track of whether a `poll_table` has ever been registered.
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 ...
|
| 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 ...
|
| f85bea18 | 09-Jul-2024 |
Miguel Ojeda <[email protected]> |
rust: allow `dead_code` for never constructed bindings
Starting with the upcoming Rust 1.80.0 (since upstream commit 35130d7233e9 ("Detect pub structs never constructed and unused associated constan
rust: allow `dead_code` for never constructed bindings
Starting with the upcoming Rust 1.80.0 (since upstream commit 35130d7233e9 ("Detect pub structs never constructed and unused associated constants in traits")), the `dead_code` pass detects more cases, which triggers in the `bindings` crate:
warning: struct `boot_params` is never constructed --> rust/bindings/bindings_generated.rs:10684:12 | 10684 | pub struct boot_params { | ^^^^^^^^^^^ | = note: `#[warn(dead_code)]` on by default
As well as in the `uapi` one:
warning: struct `boot_params` is never constructed --> rust/uapi/uapi_generated.rs:10392:12 | 10392 | pub struct boot_params { | ^^^^^^^^^^^ | = note: `#[warn(dead_code)]` on by default
These are all expected, since we do not use all the structs in the bindings that `bindgen` generates from the C headers.
Therefore, allow them.
Reviewed-by: Björn Roy Baron <[email protected]> Reviewed-by: Finn Behrens <[email protected]> Tested-by: Benno Lossin <[email protected]> Tested-by: Andreas Hindborg <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Miguel Ojeda <[email protected]>
show more ...
|
| fc6e66f4 | 28-May-2024 |
Alice Ryhl <[email protected]> |
rust: add abstraction for `struct page`
Adds a new struct called `Page` that wraps a pointer to `struct page`. This struct is assumed to hold ownership over the page, so that Rust code can allocate
rust: add abstraction for `struct page`
Adds a new struct called `Page` that wraps a pointer to `struct page`. This struct is assumed to hold ownership over the page, so that Rust code can allocate and manage pages directly.
The page type has various methods for reading and writing into the page. These methods will temporarily map the page to allow the operation. All of these methods use a helper that takes an offset and length, performs bounds checks, and returns a pointer to the given offset in the page.
This patch only adds support for pages of order zero, as that is all Rust Binder needs. However, it is written to make it easy to add support for higher-order pages in the future. To do that, you would add a const generic parameter to `Page` that specifies the order. Most of the methods do not need to be adjusted, as the logic for dealing with mapping multiple pages at once can be isolated to just the `with_pointer_into_page` method.
Rust Binder needs to manage pages directly as that is how transactions are delivered: Each process has an mmap'd region for incoming transactions. When an incoming transaction arrives, the Binder driver will choose a region in the mmap, allocate and map the relevant pages manually, and copy the incoming transaction directly into the page. This architecture allows the driver to copy transactions directly from the address space of one process to another, without an intermediate copy to a kernel buffer.
This code is based on Wedson's page abstractions from the old rust branch, but it has been modified by Alice by removing the incomplete support for higher-order pages, by introducing the `with_*` helpers to consolidate the bounds checking logic into a single place, and various other changes.
Co-developed-by: Wedson Almeida Filho <[email protected]> Signed-off-by: Wedson Almeida Filho <[email protected]> Reviewed-by: Andreas Hindborg <[email protected]> Reviewed-by: Trevor Gross <[email protected]> Reviewed-by: Benno Lossin <[email protected]> Reviewed-by: Boqun Feng <[email protected]> Signed-off-by: Alice Ryhl <[email protected]> Link: https://lore.kernel.org/r/[email protected] [ Fixed typos and added a few intra-doc links. - Miguel ] Signed-off-by: Miguel Ojeda <[email protected]>
show more ...
|