diff options
| -rw-r--r-- | rust/helpers/pci.c | 5 | ||||
| -rw-r--r-- | rust/kernel/pci.rs | 22 |
2 files changed, 26 insertions, 1 deletions
diff --git a/rust/helpers/pci.c b/rust/helpers/pci.c index 8ba22f911459..cd0e6bf2cc4d 100644 --- a/rust/helpers/pci.c +++ b/rust/helpers/pci.c @@ -16,3 +16,8 @@ resource_size_t rust_helper_pci_resource_len(struct pci_dev *pdev, int bar) { return pci_resource_len(pdev, bar); } + +bool rust_helper_dev_is_pci(const struct device *dev) +{ + return dev_is_pci(dev); +} diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs index 3664d35b8e79..38fc8d5ffbf9 100644 --- a/rust/kernel/pci.rs +++ b/rust/kernel/pci.rs @@ -6,7 +6,7 @@ use crate::{ alloc::flags::*, - bindings, device, + bindings, container_of, device, device_id::RawDeviceId, devres::Devres, driver, @@ -455,6 +455,26 @@ impl<Ctx: device::DeviceContext> AsRef<device::Device<Ctx>> for Device<Ctx> { } } +impl<Ctx: device::DeviceContext> TryFrom<&device::Device<Ctx>> for &Device<Ctx> { + type Error = kernel::error::Error; + + fn try_from(dev: &device::Device<Ctx>) -> Result<Self, Self::Error> { + // SAFETY: By the type invariant of `Device`, `dev.as_raw()` is a valid pointer to a + // `struct device`. + if !unsafe { bindings::dev_is_pci(dev.as_raw()) } { + return Err(EINVAL); + } + + // SAFETY: We've just verified that the bus type of `dev` equals `bindings::pci_bus_type`, + // hence `dev` must be embedded in a valid `struct pci_dev` as guaranteed by the + // corresponding C code. + let pdev = unsafe { container_of!(dev.as_raw(), bindings::pci_dev, dev) }; + + // SAFETY: `pdev` is a valid pointer to a `struct pci_dev`. + Ok(unsafe { &*pdev.cast() }) + } +} + // SAFETY: A `Device` is always reference-counted and can be released from any thread. unsafe impl Send for Device {} |