From: Gary Guo <[email protected]> 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 <[email protected]> Signed-off-by: Danilo Krummrich <[email protected]> --- rust/kernel/dma.rs | 77 +++++++++++++++++++++++++++++++++++----- samples/rust/rust_dma.rs | 8 ++--- 2 files changed, 73 insertions(+), 12 deletions(-) diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs index 3a692ac76ba2..291fdea3b52b 100644 --- a/rust/kernel/dma.rs +++ b/rust/kernel/dma.rs @@ -47,7 +47,7 @@ pub trait Device: AsRef<device::Device<Core>> { /// # 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 @@ unsafe fn dma_set_mask(&self, mask: DmaMask) -> Result { /// # 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 @@ unsafe fn dma_set_coherent_mask(&self, mask: DmaMask) -> Result { /// # 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 @@ unsafe fn dma_set_mask_and_coherent(&self, mask: DmaMask) -> Result { /// # 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 @@ pub const fn value(&self) -> u64 { /// /// ``` /// # use kernel::device::{Bound, Device}; -/// use kernel::dma::{attrs::*, CoherentAllocation}; +/// use kernel::dma::{attrs::*, Coherent}; /// /// # fn test(dev: &Device<Bound>) -> Result { /// let attribs = DMA_ATTR_FORCE_CONTIGUOUS | DMA_ATTR_NO_WARN; -/// let c: CoherentAllocation<u64> = -/// 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 @@ pub unsafe fn field_write<F: AsBytes>(&self, field: *mut F, val: F) { impl<T: AsBytes + FromBytes> Coherent<T> { /// Allocates a region of `T` of coherent memory. - #[expect(unused)] fn alloc_with_attrs( dev: &device::Device<Bound>, gfp_flags: kernel::alloc::Flags, @@ -529,6 +528,33 @@ fn alloc_with_attrs( }) } + /// Allocates a region of type `T` of coherent memory. + /// + /// # Examples + /// + /// ``` + /// # use kernel::device::{Bound, Device}; + /// use kernel::dma::{attrs::*, Coherent}; + /// + /// # fn test(dev: &Device<Bound>) -> Result { + /// let c: Coherent<[u64; 4]> = + /// Coherent::zeroed_with_attrs(dev, GFP_KERNEL, DMA_ATTR_NO_WARN)?; + /// # Ok::<(), Error>(()) } + /// ``` + pub fn zeroed_with_attrs( + dev: &device::Device<Bound>, + gfp_flags: kernel::alloc::Flags, + dma_attrs: Attrs, + ) -> Result<Self> { + 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. + pub fn zeroed(dev: &device::Device<Bound>, gfp_flags: kernel::alloc::Flags) -> Result<Self> { + 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<Bound>, @@ -572,6 +598,41 @@ fn alloc_slice_with_attrs( dma_attrs, }) } + + /// Allocates a zeroed region of type `T` of coherent memory. + /// + /// Unlike `Coherent::<[T; N]>::zeroed_with_attrs`, `Coherent::<T>::zeored_slices` support + /// a runtime length. + /// + /// # Examples + /// + /// ``` + /// # use kernel::device::{Bound, Device}; + /// use kernel::dma::{attrs::*, Coherent}; + /// + /// # fn test(dev: &Device<Bound>) -> Result { + /// let c: Coherent<[u64]> = + /// Coherent::zeroed_slice_with_attrs(dev, 4, GFP_KERNEL, DMA_ATTR_NO_WARN)?; + /// # Ok::<(), Error>(()) } + /// ``` + pub fn zeroed_slice_with_attrs( + dev: &device::Device<Bound>, + len: usize, + gfp_flags: kernel::alloc::Flags, + dma_attrs: Attrs, + ) -> Result<Coherent<[T]>> { + 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. + pub fn zeroed_slice( + dev: &device::Device<Bound>, + len: usize, + gfp_flags: kernel::alloc::Flags, + ) -> Result<Coherent<[T]>> { + Self::zeroed_slice_with_attrs(dev, len, gfp_flags, Attrs(0)) + } } impl<T: AsBytes + FromBytes> Coherent<[T]> { diff --git a/samples/rust/rust_dma.rs b/samples/rust/rust_dma.rs index ce39b5545097..314ef51cd86c 100644 --- a/samples/rust/rust_dma.rs +++ b/samples/rust/rust_dma.rs @@ -6,7 +6,7 @@ use kernel::{ device::Core, - dma::{CoherentAllocation, DataDirection, Device, DmaMask}, + dma::{Coherent, DataDirection, Device, DmaMask}, page, pci, prelude::*, scatterlist::{Owned, SGTable}, @@ -16,7 +16,7 @@ #[pin_data(PinnedDrop)] struct DmaSampleDriver { pdev: ARef<pci::Device>, - ca: CoherentAllocation<MyStruct>, + ca: Coherent<[MyStruct]>, #[pin] sgt: SGTable<Owned<VVec<u8>>>, } @@ -64,8 +64,8 @@ fn probe(pdev: &pci::Device<Core>, _info: &Self::IdInfo) -> impl PinInit<Self, E // SAFETY: There are no concurrent calls to DMA allocation and mapping primitives. unsafe { pdev.dma_set_mask_and_coherent(mask)? }; - let ca: CoherentAllocation<MyStruct> = - 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)); -- 2.53.0
