Add `IdPool::reserve_ids` which allocates a contiguous range with the given offset, count, and alignment.
Signed-off-by: Eliot Courtney <[email protected]> --- rust/kernel/id_pool.rs | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/rust/kernel/id_pool.rs b/rust/kernel/id_pool.rs index 9494fde701ee..382a5645767f 100644 --- a/rust/kernel/id_pool.rs +++ b/rust/kernel/id_pool.rs @@ -4,8 +4,14 @@ //! Rust API for an ID pool backed by a [`BitmapVec`]. +use core::{ + num::NonZero, + ops::Range, // +}; + use crate::alloc::{AllocError, Flags}; use crate::bitmap::BitmapVec; +use crate::ptr::Alignment; /// Represents a dynamic ID pool backed by a [`BitmapVec`]. /// @@ -244,6 +250,32 @@ pub fn find_unused_id(&mut self, offset: usize) -> Option<UnusedId<'_>> { pub fn release_id(&mut self, id: usize) { self.map.clear_bit(id); } + + /// Reserves a contiguous area of `count` IDs at or after `offset`. + /// + /// The start of the returned area is a multiple of `align`. + /// + /// Returns the reserved range upon success, or [`None`] if no such area could be found. + #[inline] + #[must_use] + pub fn reserve_ids( + &mut self, + offset: usize, + count: NonZero<usize>, + align: Alignment, + ) -> Option<Range<usize>> { + let start = self.map.next_zero_area(offset, count, align)?; + self.map.set(start, count); + Some(start..start + count.get()) + } + + /// Releases a contiguous area of IDs. + #[inline] + pub fn release_ids(&mut self, range: &Range<usize>) { + if let Some(nbits) = NonZero::new(range.len()) { + self.map.clear(range.start, nbits); + } + } } /// Represents an unused id in an [`IdPool`]. -- 2.55.0
