diff options
Diffstat (limited to 'samples/rust/rust_dma.rs')
-rw-r--r-- | samples/rust/rust_dma.rs | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/samples/rust/rust_dma.rs b/samples/rust/rust_dma.rs new file mode 100644 index 000000000000..874c2c964afa --- /dev/null +++ b/samples/rust/rust_dma.rs @@ -0,0 +1,97 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Rust DMA api test (based on QEMU's `pci-testdev`). +//! +//! To make this driver probe, QEMU must be run with `-device pci-testdev`. + +use kernel::{bindings, device::Core, dma::CoherentAllocation, pci, prelude::*, types::ARef}; + +struct DmaSampleDriver { + pdev: ARef<pci::Device>, + ca: CoherentAllocation<MyStruct>, +} + +const TEST_VALUES: [(u32, u32); 5] = [ + (0xa, 0xb), + (0xc, 0xd), + (0xe, 0xf), + (0xab, 0xba), + (0xcd, 0xef), +]; + +struct MyStruct { + h: u32, + b: u32, +} + +impl MyStruct { + fn new(h: u32, b: u32) -> Self { + Self { h, b } + } +} +// SAFETY: All bit patterns are acceptable values for `MyStruct`. +unsafe impl kernel::transmute::AsBytes for MyStruct {} +// SAFETY: Instances of `MyStruct` have no uninitialized portions. +unsafe impl kernel::transmute::FromBytes for MyStruct {} + +kernel::pci_device_table!( + PCI_TABLE, + MODULE_PCI_TABLE, + <DmaSampleDriver as pci::Driver>::IdInfo, + [( + pci::DeviceId::from_id(bindings::PCI_VENDOR_ID_REDHAT, 0x5), + () + )] +); + +impl pci::Driver for DmaSampleDriver { + type IdInfo = (); + const ID_TABLE: pci::IdTable<Self::IdInfo> = &PCI_TABLE; + + fn probe(pdev: &pci::Device<Core>, _info: &Self::IdInfo) -> Result<Pin<KBox<Self>>> { + dev_info!(pdev.as_ref(), "Probe DMA test driver.\n"); + + let ca: CoherentAllocation<MyStruct> = + CoherentAllocation::alloc_coherent(pdev.as_ref(), TEST_VALUES.len(), GFP_KERNEL)?; + + || -> Result { + for (i, value) in TEST_VALUES.into_iter().enumerate() { + kernel::dma_write!(ca[i] = MyStruct::new(value.0, value.1)); + } + + Ok(()) + }()?; + + let drvdata = KBox::new( + Self { + pdev: pdev.into(), + ca, + }, + GFP_KERNEL, + )?; + + Ok(drvdata.into()) + } +} + +impl Drop for DmaSampleDriver { + fn drop(&mut self) { + dev_info!(self.pdev.as_ref(), "Unload DMA test driver.\n"); + + let _ = || -> Result { + for (i, value) in TEST_VALUES.into_iter().enumerate() { + assert_eq!(kernel::dma_read!(self.ca[i].h), value.0); + assert_eq!(kernel::dma_read!(self.ca[i].b), value.1); + } + Ok(()) + }(); + } +} + +kernel::module_pci_driver! { + type: DmaSampleDriver, + name: "rust_dma", + authors: ["Abdiel Janulgue"], + description: "Rust DMA test", + license: "GPL v2", +} |