rust: support `srctree`-relative links
Some of our links use relative paths in order to point to files in the
source tree, e.g.:
//! C header: [`include/linux/printk.h`](../../../../include/linux/printk.h)
/// [`struct mutex`]: ../../../../include/linux/mutex.h
These are problematic because they are hard to maintain and do not support
`O=` builds.
Instead, provide support for `srctree`-relative links, e.g.:
//! C header: [`include/linux/printk.h`](srctree/include/linux/printk.h)
/// [`struct mutex`]: srctree/include/linux/mutex.h
The links are fixed after `rustdoc` generation to be based on the absolute
path to the source tree.
Essentially, this is the automatic version of Tomonori's fix [1],
suggested by Gary [2].
Suggested-by: Gary Guo <gary@garyguo.net>
Reported-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Closes: https://lore.kernel.org/r/20231026.204058.2167744626131849993.fujita.tomonori@gmail.com [1]
Fixes: 48fadf440075 ("docs: Move rustdoc output, cross-reference it")
Link: https://lore.kernel.org/rust-for-linux/20231026154525.6d14b495@eugeo/ [2]
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20231215235428.243211-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
diff --git a/Documentation/rust/coding-guidelines.rst b/Documentation/rust/coding-guidelines.rst
index aa8ed082..0554284 100644
--- a/Documentation/rust/coding-guidelines.rst
+++ b/Documentation/rust/coding-guidelines.rst
@@ -177,6 +177,19 @@
https://doc.rust-lang.org/rustdoc/how-to-write-documentation.html
+In addition, the kernel supports creating links relative to the source tree by
+prefixing the link destination with ``srctree/``. For instance:
+
+.. code-block:: rust
+
+ //! C header: [`include/linux/printk.h`](srctree/include/linux/printk.h)
+
+or:
+
+.. code-block:: rust
+
+ /// [`struct mutex`]: srctree/include/linux/mutex.h
+
Naming
------
diff --git a/rust/Makefile b/rust/Makefile
index 5a3e314..9d2a16cc 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -99,7 +99,8 @@
$(Q)find $(rustdoc_output) -name '*.html' -type f -print0 | xargs -0 sed -Ei \
-e 's:rust-logo-[0-9a-f]+\.svg:logo.svg:g' \
-e 's:favicon-[0-9a-f]+\.svg:logo.svg:g' \
- -e 's:<link rel="alternate icon" type="image/png" href="[/.]+/static\.files/favicon-(16x16|32x32)-[0-9a-f]+\.png">::g'
+ -e 's:<link rel="alternate icon" type="image/png" href="[/.]+/static\.files/favicon-(16x16|32x32)-[0-9a-f]+\.png">::g' \
+ -e 's:<a href="srctree/([^"]+)">:<a href="$(abs_srctree)/\1">:g'
$(Q)for f in $(rustdoc_output)/static.files/rustdoc-*.css; do \
echo ".logo-container > img { object-fit: contain; }" >> $$f; done
diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs
index 376280b..4f0c1ed 100644
--- a/rust/kernel/error.rs
+++ b/rust/kernel/error.rs
@@ -2,7 +2,7 @@
//! Kernel errors.
//!
-//! C header: [`include/uapi/asm-generic/errno-base.h`](../../../include/uapi/asm-generic/errno-base.h)
+//! C header: [`include/uapi/asm-generic/errno-base.h`](srctree/include/uapi/asm-generic/errno-base.h)
use crate::str::CStr;
diff --git a/rust/kernel/ioctl.rs b/rust/kernel/ioctl.rs
index c49e1a8..f1d42ab 100644
--- a/rust/kernel/ioctl.rs
+++ b/rust/kernel/ioctl.rs
@@ -2,7 +2,7 @@
//! ioctl() number definitions
//!
-//! C header: [`include/asm-generic/ioctl.h`](../../../../include/asm-generic/ioctl.h)
+//! C header: [`include/asm-generic/ioctl.h`](srctree/include/asm-generic/ioctl.h)
#![allow(non_snake_case)]
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 722655b..0ba7727 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -2,7 +2,7 @@
//! KUnit-based macros for Rust unit tests.
//!
-//! C header: [`include/kunit/test.h`](../../../../../include/kunit/test.h)
+//! C header: [`include/kunit/test.h`](srctree/include/kunit/test.h)
//!
//! Reference: <https://docs.kernel.org/dev-tools/kunit/index.html>
diff --git a/rust/kernel/print.rs b/rust/kernel/print.rs
index f48926e..9b13aca 100644
--- a/rust/kernel/print.rs
+++ b/rust/kernel/print.rs
@@ -2,7 +2,7 @@
//! Printing facilities.
//!
-//! C header: [`include/linux/printk.h`](../../../../include/linux/printk.h)
+//! C header: [`include/linux/printk.h`](srctree/include/linux/printk.h)
//!
//! Reference: <https://www.kernel.org/doc/html/latest/core-api/printk-basics.html>
@@ -48,7 +48,7 @@ pub mod format_strings {
/// The format string is always the same for a given level, i.e. for a
/// given `prefix`, which are the kernel's `KERN_*` constants.
///
- /// [`_printk`]: ../../../../include/linux/printk.h
+ /// [`_printk`]: srctree/include/linux/printk.h
const fn generate(is_cont: bool, prefix: &[u8; 3]) -> [u8; LENGTH] {
// Ensure the `KERN_*` macros are what we expect.
assert!(prefix[0] == b'\x01');
@@ -97,7 +97,7 @@ pub mod format_strings {
/// The format string must be one of the ones in [`format_strings`], and
/// the module name must be null-terminated.
///
-/// [`_printk`]: ../../../../include/linux/_printk.h
+/// [`_printk`]: srctree/include/linux/_printk.h
#[doc(hidden)]
#[cfg_attr(not(CONFIG_PRINTK), allow(unused_variables))]
pub unsafe fn call_printk(
@@ -120,7 +120,7 @@ pub unsafe fn call_printk(
///
/// Public but hidden since it should only be used from public macros.
///
-/// [`_printk`]: ../../../../include/linux/printk.h
+/// [`_printk`]: srctree/include/linux/printk.h
#[doc(hidden)]
#[cfg_attr(not(CONFIG_PRINTK), allow(unused_variables))]
pub fn call_printk_cont(args: fmt::Arguments<'_>) {
diff --git a/rust/kernel/sync/condvar.rs b/rust/kernel/sync/condvar.rs
index 8630faa..f65e19d 100644
--- a/rust/kernel/sync/condvar.rs
+++ b/rust/kernel/sync/condvar.rs
@@ -69,7 +69,7 @@ macro_rules! new_condvar {
/// }
/// ```
///
-/// [`struct wait_queue_head`]: ../../../include/linux/wait.h
+/// [`struct wait_queue_head`]: srctree/include/linux/wait.h
#[pin_data]
pub struct CondVar {
#[pin]
diff --git a/rust/kernel/sync/lock/mutex.rs b/rust/kernel/sync/lock/mutex.rs
index 09276fe..8c524a3 100644
--- a/rust/kernel/sync/lock/mutex.rs
+++ b/rust/kernel/sync/lock/mutex.rs
@@ -84,7 +84,7 @@ macro_rules! new_mutex {
/// }
/// ```
///
-/// [`struct mutex`]: ../../../../include/linux/mutex.h
+/// [`struct mutex`]: srctree/include/linux/mutex.h
pub type Mutex<T> = super::Lock<T, MutexBackend>;
/// A kernel `struct mutex` lock backend.
diff --git a/rust/kernel/sync/lock/spinlock.rs b/rust/kernel/sync/lock/spinlock.rs
index 91eb2c9..068535c 100644
--- a/rust/kernel/sync/lock/spinlock.rs
+++ b/rust/kernel/sync/lock/spinlock.rs
@@ -82,7 +82,7 @@ macro_rules! new_spinlock {
/// }
/// ```
///
-/// [`spinlock_t`]: ../../../../include/linux/spinlock.h
+/// [`spinlock_t`]: srctree/include/linux/spinlock.h
pub type SpinLock<T> = super::Lock<T, SpinLockBackend>;
/// A kernel `spinlock_t` lock backend.
diff --git a/rust/kernel/task.rs b/rust/kernel/task.rs
index b2299bc..9451932d 100644
--- a/rust/kernel/task.rs
+++ b/rust/kernel/task.rs
@@ -2,7 +2,7 @@
//! Tasks (threads and processes).
//!
-//! C header: [`include/linux/sched.h`](../../../../include/linux/sched.h).
+//! C header: [`include/linux/sched.h`](srctree/include/linux/sched.h).
use crate::{bindings, types::Opaque};
use core::{marker::PhantomData, ops::Deref, ptr};
diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs
index b67fb1b..4983978 100644
--- a/rust/kernel/workqueue.rs
+++ b/rust/kernel/workqueue.rs
@@ -132,7 +132,7 @@
//! }
//! ```
//!
-//! C header: [`include/linux/workqueue.h`](../../../../include/linux/workqueue.h)
+//! C header: [`include/linux/workqueue.h`](srctree/include/linux/workqueue.h)
use crate::{bindings, prelude::*, sync::Arc, sync::LockClassKey, types::Opaque};
use alloc::alloc::AllocError;
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index d18a3e7..f489f31 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -20,7 +20,7 @@
/// The `type` argument should be a type which implements the [`Module`]
/// trait. Also accepts various forms of kernel metadata.
///
-/// C header: [`include/linux/moduleparam.h`](../../../include/linux/moduleparam.h)
+/// C header: [`include/linux/moduleparam.h`](srctree/include/linux/moduleparam.h)
///
/// [`Module`]: ../kernel/trait.Module.html
///