From 79cf41692aadc3d0ac9b1d8e2c2f620ce2103918 Mon Sep 17 00:00:00 2001 From: Alexandre Courbot Date: Sat, 14 Mar 2026 10:06:19 +0900 Subject: sample: rust: pci: use `register!` macro Convert the direct IO accesses to properly defined registers. Tested-by: Zhi Wang Signed-off-by: Alexandre Courbot Link: https://patch.msgid.link/20260314-register-v9-9-86805b2f7e9d@nvidia.com [ Fix up kernel import style. - Danilo ] Signed-off-by: Danilo Krummrich --- samples/rust/rust_driver_pci.rs | 90 +++++++++++++++++++++++++++++++---------- 1 file changed, 68 insertions(+), 22 deletions(-) (limited to 'samples') diff --git a/samples/rust/rust_driver_pci.rs b/samples/rust/rust_driver_pci.rs index d3d4a7931deb..47d3e84fab63 100644 --- a/samples/rust/rust_driver_pci.rs +++ b/samples/rust/rust_driver_pci.rs @@ -5,30 +5,63 @@ //! To make this driver probe, QEMU must be run with `-device pci-testdev`. use kernel::{ - device::Bound, - device::Core, + device::{ + Bound, + Core, // + }, devres::Devres, - io::Io, + io::{ + register, + register::Array, + Io, // + }, + num::Bounded, pci, prelude::*, sync::aref::ARef, // }; -struct Regs; +mod regs { + use super::*; -impl Regs { - const TEST: usize = 0x0; - const OFFSET: usize = 0x4; - const DATA: usize = 0x8; - const COUNT: usize = 0xC; - const END: usize = 0x10; + register! { + pub(super) TEST(u8) @ 0x0 { + 7:0 index => TestIndex; + } + + pub(super) OFFSET(u32) @ 0x4 { + 31:0 offset; + } + + pub(super) DATA(u8) @ 0x8 { + 7:0 data; + } + + pub(super) COUNT(u32) @ 0xC { + 31:0 count; + } + } + + pub(super) const END: usize = 0x10; } -type Bar0 = pci::Bar<{ Regs::END }>; +type Bar0 = pci::Bar<{ regs::END }>; #[derive(Copy, Clone, Debug)] struct TestIndex(u8); +impl From> for TestIndex { + fn from(value: Bounded) -> Self { + Self(value.into()) + } +} + +impl From for Bounded { + fn from(value: TestIndex) -> Self { + value.0.into() + } +} + impl TestIndex { const NO_EVENTFD: Self = Self(0); } @@ -54,40 +87,53 @@ kernel::pci_device_table!( impl SampleDriver { fn testdev(index: &TestIndex, bar: &Bar0) -> Result { // Select the test. - bar.write8(index.0, Regs::TEST); + bar.write_reg(regs::TEST::zeroed().with_index(*index)); - let offset = bar.read32(Regs::OFFSET) as usize; - let data = bar.read8(Regs::DATA); + let offset = bar.read(regs::OFFSET).into_raw() as usize; + let data = bar.read(regs::DATA).into(); // Write `data` to `offset` to increase `count` by one. // // Note that we need `try_write8`, since `offset` can't be checked at compile-time. bar.try_write8(data, offset)?; - Ok(bar.read32(Regs::COUNT)) + Ok(bar.read(regs::COUNT).into()) } fn config_space(pdev: &pci::Device) { let config = pdev.config_space(); - // TODO: use the register!() macro for defining PCI configuration space registers once it - // has been move out of nova-core. + // Some PCI configuration space registers. + register! { + VENDOR_ID(u16) @ 0x0 { + 15:0 vendor_id; + } + + REVISION_ID(u8) @ 0x8 { + 7:0 revision_id; + } + + BAR(u32)[6] @ 0x10 { + 31:0 value; + } + } + dev_info!( pdev, "pci-testdev config space read8 rev ID: {:x}\n", - config.read8(0x8) + config.read(REVISION_ID).revision_id() ); dev_info!( pdev, "pci-testdev config space read16 vendor ID: {:x}\n", - config.read16(0) + config.read(VENDOR_ID).vendor_id() ); dev_info!( pdev, "pci-testdev config space read32 BAR 0: {:x}\n", - config.read32(0x10) + config.read(BAR::at(0)).value() ); } } @@ -111,7 +157,7 @@ impl pci::Driver for SampleDriver { pdev.set_master(); Ok(try_pin_init!(Self { - bar <- pdev.iomap_region_sized::<{ Regs::END }>(0, c"rust_driver_pci"), + bar <- pdev.iomap_region_sized::<{ regs::END }>(0, c"rust_driver_pci"), index: *info, _: { let bar = bar.access(pdev.as_ref())?; @@ -131,7 +177,7 @@ impl pci::Driver for SampleDriver { fn unbind(pdev: &pci::Device, this: Pin<&Self>) { if let Ok(bar) = this.bar.access(pdev.as_ref()) { // Reset pci-testdev by writing a new test index. - bar.write8(this.index.0, Regs::TEST); + bar.write_reg(regs::TEST::zeroed().with_index(this.index)); } } } -- cgit v1.2.3 From f84ecffa3f745572164c1269f20eec2589d432c9 Mon Sep 17 00:00:00 2001 From: Gary Guo Date: Fri, 20 Mar 2026 20:45:38 +0100 Subject: rust: dma: add zeroed constructor to `Coherent` These constructors create a coherent container of a single object instead of slice. They are named `zeroed` and `zeroed_with_attrs` to emphasis that they are created initialized zeroed. It is intended that there'll be new constructors that take `PinInit` instead of zeroing. Signed-off-by: Gary Guo Reviewed-by: Alice Ryhl Reviewed-by: Alexandre Courbot Link: https://patch.msgid.link/20260320194626.36263-4-dakr@kernel.org [ Use kernel import style. - Danilo ] Signed-off-by: Danilo Krummrich --- rust/kernel/dma.rs | 93 +++++++++++++++++++++++++++++++++++++++++++----- samples/rust/rust_dma.rs | 13 ++++--- 2 files changed, 94 insertions(+), 12 deletions(-) (limited to 'samples') diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs index ff3e147f1a23..59477c865dd3 100644 --- a/rust/kernel/dma.rs +++ b/rust/kernel/dma.rs @@ -47,7 +47,7 @@ pub trait Device: AsRef> { /// # Safety /// /// This method must not be called concurrently with any DMA allocation or mapping primitives, - /// such as [`CoherentAllocation::alloc_attrs`]. + /// such as [`Coherent::zeroed`]. unsafe fn dma_set_mask(&self, mask: DmaMask) -> Result { // SAFETY: // - By the type invariant of `device::Device`, `self.as_ref().as_raw()` is valid. @@ -64,7 +64,7 @@ pub trait Device: AsRef> { /// # Safety /// /// This method must not be called concurrently with any DMA allocation or mapping primitives, - /// such as [`CoherentAllocation::alloc_attrs`]. + /// such as [`Coherent::zeroed`]. unsafe fn dma_set_coherent_mask(&self, mask: DmaMask) -> Result { // SAFETY: // - By the type invariant of `device::Device`, `self.as_ref().as_raw()` is valid. @@ -83,7 +83,7 @@ pub trait Device: AsRef> { /// # Safety /// /// This method must not be called concurrently with any DMA allocation or mapping primitives, - /// such as [`CoherentAllocation::alloc_attrs`]. + /// such as [`Coherent::zeroed`]. unsafe fn dma_set_mask_and_coherent(&self, mask: DmaMask) -> Result { // SAFETY: // - By the type invariant of `device::Device`, `self.as_ref().as_raw()` is valid. @@ -102,7 +102,7 @@ pub trait Device: AsRef> { /// # Safety /// /// This method must not be called concurrently with any DMA allocation or mapping primitives, - /// such as [`CoherentAllocation::alloc_attrs`]. + /// such as [`Coherent::zeroed`]. unsafe fn dma_set_max_seg_size(&self, size: u32) { // SAFETY: // - By the type invariant of `device::Device`, `self.as_ref().as_raw()` is valid. @@ -202,12 +202,12 @@ impl DmaMask { /// /// ``` /// # use kernel::device::{Bound, Device}; -/// use kernel::dma::{attrs::*, CoherentAllocation}; +/// use kernel::dma::{attrs::*, Coherent}; /// /// # fn test(dev: &Device) -> Result { /// let attribs = DMA_ATTR_FORCE_CONTIGUOUS | DMA_ATTR_NO_WARN; -/// let c: CoherentAllocation = -/// CoherentAllocation::alloc_attrs(dev, 4, GFP_KERNEL, attribs)?; +/// let c: Coherent<[u64]> = +/// Coherent::zeroed_slice_with_attrs(dev, 4, GFP_KERNEL, attribs)?; /// # Ok::<(), Error>(()) } /// ``` #[derive(Clone, Copy, PartialEq)] @@ -492,7 +492,6 @@ impl Coherent { impl Coherent { /// Allocates a region of `T` of coherent memory. - #[expect(unused)] fn alloc_with_attrs( dev: &device::Device, gfp_flags: kernel::alloc::Flags, @@ -529,6 +528,41 @@ impl Coherent { }) } + /// Allocates a region of type `T` of coherent memory. + /// + /// # Examples + /// + /// ``` + /// # use kernel::device::{ + /// # Bound, + /// # Device, + /// # }; + /// use kernel::dma::{ + /// attrs::*, + /// Coherent, + /// }; + /// + /// # fn test(dev: &Device) -> Result { + /// let c: Coherent<[u64; 4]> = + /// Coherent::zeroed_with_attrs(dev, GFP_KERNEL, DMA_ATTR_NO_WARN)?; + /// # Ok::<(), Error>(()) } + /// ``` + #[inline] + pub fn zeroed_with_attrs( + dev: &device::Device, + gfp_flags: kernel::alloc::Flags, + dma_attrs: Attrs, + ) -> Result { + Self::alloc_with_attrs(dev, gfp_flags | __GFP_ZERO, dma_attrs) + } + + /// Performs the same functionality as [`Coherent::zeroed_with_attrs`], except the + /// `dma_attrs` is 0 by default. + #[inline] + pub fn zeroed(dev: &device::Device, gfp_flags: kernel::alloc::Flags) -> Result { + Self::zeroed_with_attrs(dev, gfp_flags, Attrs(0)) + } + /// Allocates a region of `[T; len]` of coherent memory. fn alloc_slice_with_attrs( dev: &device::Device, @@ -572,6 +606,49 @@ impl Coherent { dma_attrs, }) } + + /// Allocates a zeroed region of type `T` of coherent memory. + /// + /// Unlike `Coherent::<[T; N]>::zeroed_with_attrs`, `Coherent::::zeroed_slices` support + /// a runtime length. + /// + /// # Examples + /// + /// ``` + /// # use kernel::device::{ + /// # Bound, + /// # Device, + /// # }; + /// use kernel::dma::{ + /// attrs::*, + /// Coherent, + /// }; + /// + /// # fn test(dev: &Device) -> Result { + /// let c: Coherent<[u64]> = + /// Coherent::zeroed_slice_with_attrs(dev, 4, GFP_KERNEL, DMA_ATTR_NO_WARN)?; + /// # Ok::<(), Error>(()) } + /// ``` + #[inline] + pub fn zeroed_slice_with_attrs( + dev: &device::Device, + len: usize, + gfp_flags: kernel::alloc::Flags, + dma_attrs: Attrs, + ) -> Result> { + Coherent::alloc_slice_with_attrs(dev, len, gfp_flags | __GFP_ZERO, dma_attrs) + } + + /// Performs the same functionality as [`Coherent::zeroed_slice_with_attrs`], except the + /// `dma_attrs` is 0 by default. + #[inline] + pub fn zeroed_slice( + dev: &device::Device, + len: usize, + gfp_flags: kernel::alloc::Flags, + ) -> Result> { + Self::zeroed_slice_with_attrs(dev, len, gfp_flags, Attrs(0)) + } } impl Coherent<[T]> { diff --git a/samples/rust/rust_dma.rs b/samples/rust/rust_dma.rs index ce39b5545097..129bb4b39c04 100644 --- a/samples/rust/rust_dma.rs +++ b/samples/rust/rust_dma.rs @@ -6,7 +6,12 @@ use kernel::{ device::Core, - dma::{CoherentAllocation, DataDirection, Device, DmaMask}, + dma::{ + Coherent, + DataDirection, + Device, + DmaMask, // + }, page, pci, prelude::*, scatterlist::{Owned, SGTable}, @@ -16,7 +21,7 @@ use kernel::{ #[pin_data(PinnedDrop)] struct DmaSampleDriver { pdev: ARef, - ca: CoherentAllocation, + ca: Coherent<[MyStruct]>, #[pin] sgt: SGTable>>, } @@ -64,8 +69,8 @@ impl pci::Driver for DmaSampleDriver { // SAFETY: There are no concurrent calls to DMA allocation and mapping primitives. unsafe { pdev.dma_set_mask_and_coherent(mask)? }; - let ca: CoherentAllocation = - CoherentAllocation::alloc_coherent(pdev.as_ref(), TEST_VALUES.len(), GFP_KERNEL)?; + let ca: Coherent<[MyStruct]> = + Coherent::zeroed_slice(pdev.as_ref(), TEST_VALUES.len(), GFP_KERNEL)?; for (i, value) in TEST_VALUES.into_iter().enumerate() { kernel::dma_write!(ca, [i]?, MyStruct::new(value.0, value.1)); -- cgit v1.2.3