Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
rust: device: implement Device::parent()
Device::parent() returns a reference to the device' parent device, if
any.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250414131934.28418-3-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
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rust/kernel/device.rs
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rust/kernel/device.rs
···
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self.0.get()
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}
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/// Returns a reference to the parent device, if any.
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#[expect(unused)]
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pub(crate) fn parent(&self) -> Option<&Self> {
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// SAFETY:
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// - By the type invariant `self.as_raw()` is always valid.
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// - The parent device is only ever set at device creation.
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let parent = unsafe { (*self.as_raw()).parent };
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if parent.is_null() {
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None
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} else {
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// SAFETY:
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// - Since `parent` is not NULL, it must be a valid pointer to a `struct device`.
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// - `parent` is valid for the lifetime of `self`, since a `struct device` holds a
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// reference count of its parent.
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Some(unsafe { Self::as_ref(parent) })
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}
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}
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/// Convert a raw C `struct device` pointer to a `&'a Device`.
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///
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/// # Safety