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-rw-r--r--vendor/redox_syscall/src/io/dma.rs219
1 files changed, 0 insertions, 219 deletions
diff --git a/vendor/redox_syscall/src/io/dma.rs b/vendor/redox_syscall/src/io/dma.rs
deleted file mode 100644
index 0613fc9..0000000
--- a/vendor/redox_syscall/src/io/dma.rs
+++ /dev/null
@@ -1,219 +0,0 @@
-use core::mem::{self, MaybeUninit};
-use core::ops::{Deref, DerefMut};
-use core::{ptr, slice};
-
-use crate::Result;
-use crate::{PartialAllocStrategy, PhysallocFlags, PhysmapFlags};
-use crate::arch::PAGE_SIZE;
-
-/// An RAII guard of a physical memory allocation. Currently all physically allocated memory are
-/// page-aligned and take up at least 4k of space (on x86_64).
-#[derive(Debug)]
-pub struct PhysBox {
- address: usize,
- size: usize
-}
-
-const fn round_up(x: usize) -> usize {
- (x + PAGE_SIZE - 1) / PAGE_SIZE * PAGE_SIZE
-}
-fn assert_aligned(x: usize) {
- assert_eq!(x % PAGE_SIZE, 0);
-}
-
-#[cfg(target_arch = "aarch64")]
-fn physmap_flags() -> PhysmapFlags {
- // aarch64 currently must map DMA memory without caching to ensure coherence
- crate::PHYSMAP_NO_CACHE | crate::PHYSMAP_WRITE
-}
-
-#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
-fn physmap_flags() -> PhysmapFlags {
- // x86 ensures cache coherence with DMA memory
- crate::PHYSMAP_WRITE
-}
-
-impl PhysBox {
- /// Construct a PhysBox from an address and a size. The address must be page-aligned, and the
- /// size must similarly be a multiple of the page size.
- ///
- /// # Safety
- /// This function is unsafe because when dropping, Self has to a valid allocation.
- pub unsafe fn from_raw_parts(address: usize, size: usize) -> Self {
- assert_aligned(address);
- assert_aligned(size);
-
- Self {
- address,
- size,
- }
- }
-
- /// Retrieve the byte address in physical memory, of this allocation.
- pub fn address(&self) -> usize {
- self.address
- }
-
- /// Retrieve the size in bytes of the alloc.
- pub fn size(&self) -> usize {
- self.size
- }
-
- /// Allocate physical memory that must reside in 32-bit space.
- pub fn new_in_32bit_space(size: usize) -> Result<Self> {
- Self::new_with_flags(size, PhysallocFlags::SPACE_32)
- }
-
- pub fn new_with_flags(size: usize, flags: PhysallocFlags) -> Result<Self> {
- assert!(!flags.contains(PhysallocFlags::PARTIAL_ALLOC));
- assert_aligned(size);
-
- let address = unsafe { crate::physalloc2(size, flags.bits())? };
- Ok(unsafe { Self::from_raw_parts(address, size) })
- }
-
- /// "Partially" allocate physical memory, in the sense that the allocation may be smaller than
- /// expected, but still with a minimum limit. This is particularly useful when the physical
- /// memory space is fragmented, and a device supports scatter-gather I/O. In that case, the
- /// driver can optimistically request e.g. 1 alloc of 1 MiB, with the minimum of 512 KiB. If
- /// that first allocation only returns half the size, the driver can do another allocation
- /// and then let the device use both buffers.
- pub fn new_partial_allocation(size: usize, flags: PhysallocFlags, strategy: Option<PartialAllocStrategy>, mut min: usize) -> Result<Self> {
- assert_aligned(size);
- debug_assert!(!(flags.contains(PhysallocFlags::PARTIAL_ALLOC) && strategy.is_none()));
-
- let address = unsafe { crate::physalloc3(size, flags.bits() | strategy.map_or(0, |s| s as usize), &mut min)? };
- Ok(unsafe { Self::from_raw_parts(address, size) })
- }
-
- pub fn new(size: usize) -> Result<Self> {
- assert_aligned(size);
-
- let address = unsafe { crate::physalloc(size)? };
- Ok(unsafe { Self::from_raw_parts(address, size) })
- }
-}
-
-impl Drop for PhysBox {
- fn drop(&mut self) {
- let _ = unsafe { crate::physfree(self.address, self.size) };
- }
-}
-
-pub struct Dma<T: ?Sized> {
- phys: PhysBox,
- virt: *mut T,
-}
-
-impl<T> Dma<T> {
- pub fn from_physbox_uninit(phys: PhysBox) -> Result<Dma<MaybeUninit<T>>> {
- let virt = unsafe { crate::physmap(phys.address, phys.size, physmap_flags())? } as *mut MaybeUninit<T>;
-
- Ok(Dma {
- phys,
- virt,
- })
- }
- pub fn from_physbox_zeroed(phys: PhysBox) -> Result<Dma<MaybeUninit<T>>> {
- let this = Self::from_physbox_uninit(phys)?;
- unsafe { ptr::write_bytes(this.virt as *mut MaybeUninit<u8>, 0, this.phys.size) }
- Ok(this)
- }
-
- pub fn from_physbox(phys: PhysBox, value: T) -> Result<Self> {
- let this = Self::from_physbox_uninit(phys)?;
-
- Ok(unsafe {
- ptr::write(this.virt, MaybeUninit::new(value));
- this.assume_init()
- })
- }
-
- pub fn new(value: T) -> Result<Self> {
- let phys = PhysBox::new(round_up(mem::size_of::<T>()))?;
- Self::from_physbox(phys, value)
- }
- pub fn zeroed() -> Result<Dma<MaybeUninit<T>>> {
- let phys = PhysBox::new(round_up(mem::size_of::<T>()))?;
- Self::from_physbox_zeroed(phys)
- }
-}
-
-impl<T> Dma<MaybeUninit<T>> {
- pub unsafe fn assume_init(self) -> Dma<T> {
- let &Dma { phys: PhysBox { address, size }, virt } = &self;
- mem::forget(self);
-
- Dma {
- phys: PhysBox { address, size },
- virt: virt as *mut T,
- }
- }
-}
-impl<T: ?Sized> Dma<T> {
- pub fn physical(&self) -> usize {
- self.phys.address()
- }
- pub fn size(&self) -> usize {
- self.phys.size()
- }
- pub fn phys(&self) -> &PhysBox {
- &self.phys
- }
-}
-
-impl<T> Dma<[T]> {
- pub fn from_physbox_uninit_unsized(phys: PhysBox, len: usize) -> Result<Dma<[MaybeUninit<T>]>> {
- let max_len = phys.size() / mem::size_of::<T>();
- assert!(len <= max_len);
-
- Ok(Dma {
- virt: unsafe { slice::from_raw_parts_mut(crate::physmap(phys.address, phys.size, physmap_flags())? as *mut MaybeUninit<T>, len) } as *mut [MaybeUninit<T>],
- phys,
- })
- }
- pub fn from_physbox_zeroed_unsized(phys: PhysBox, len: usize) -> Result<Dma<[MaybeUninit<T>]>> {
- let this = Self::from_physbox_uninit_unsized(phys, len)?;
- unsafe { ptr::write_bytes(this.virt as *mut MaybeUninit<u8>, 0, this.phys.size()) }
- Ok(this)
- }
- /// Creates a new DMA buffer with a size only known at runtime.
- /// ## Safety
- /// * `T` must be properly aligned.
- /// * `T` must be valid as zeroed (i.e. no NonNull pointers).
- pub unsafe fn zeroed_unsized(count: usize) -> Result<Self> {
- let phys = PhysBox::new(round_up(mem::size_of::<T>() * count))?;
- Ok(Self::from_physbox_zeroed_unsized(phys, count)?.assume_init())
- }
-}
-impl<T> Dma<[MaybeUninit<T>]> {
- pub unsafe fn assume_init(self) -> Dma<[T]> {
- let &Dma { phys: PhysBox { address, size }, virt } = &self;
- mem::forget(self);
-
- Dma {
- phys: PhysBox { address, size },
- virt: virt as *mut [T],
- }
- }
-}
-
-impl<T: ?Sized> Deref for Dma<T> {
- type Target = T;
- fn deref(&self) -> &T {
- unsafe { &*self.virt }
- }
-}
-
-impl<T: ?Sized> DerefMut for Dma<T> {
- fn deref_mut(&mut self) -> &mut T {
- unsafe { &mut *self.virt }
- }
-}
-
-impl<T: ?Sized> Drop for Dma<T> {
- fn drop(&mut self) {
- unsafe { ptr::drop_in_place(self.virt) }
- let _ = unsafe { crate::funmap(self.virt as *mut u8 as usize, self.phys.size) };
- }
-}