Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
rust: pci: impl TryFrom<&Device> for &pci::Device
Implement TryFrom<&device::Device> for &Device.
This allows us to get a &pci::Device from a generic &Device in a safe
way; the conversion fails if the device' bus type does not match with
the PCI bus type.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250321214826.140946-3-dakr@kernel.org
[ Support device context types, use dev_is_pci() helper. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
+26
-1
+5
rust/helpers/pci.c
+5
rust/helpers/pci.c
+21
-1
rust/kernel/pci.rs
+21
-1
rust/kernel/pci.rs
···
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6
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use crate::{
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alloc::flags::*,
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-
bindings, device,
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+
bindings, container_of, device,
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device_id::RawDeviceId,
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devres::Devres,
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driver,
···
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// SAFETY: `dev` points to a valid `struct device`.
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unsafe { device::Device::as_ref(dev) }
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+
}
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}
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impl<Ctx: device::DeviceContext> TryFrom<&device::Device<Ctx>> for &Device<Ctx> {
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type Error = kernel::error::Error;
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fn try_from(dev: &device::Device<Ctx>) -> Result<Self, Self::Error> {
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// SAFETY: By the type invariant of `Device`, `dev.as_raw()` is a valid pointer to a
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// `struct device`.
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if !unsafe { bindings::dev_is_pci(dev.as_raw()) } {
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return Err(EINVAL);
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}
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// SAFETY: We've just verified that the bus type of `dev` equals `bindings::pci_bus_type`,
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// hence `dev` must be embedded in a valid `struct pci_dev` as guaranteed by the
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// corresponding C code.
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let pdev = unsafe { container_of!(dev.as_raw(), bindings::pci_dev, dev) };
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// SAFETY: `pdev` is a valid pointer to a `struct pci_dev`.
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Ok(unsafe { &*pdev.cast() })
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}
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}
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