[PATCH v4 3/6] rust: bitmap: rename IdPool::new to with_capacity

Alice Ryhl
2025-11-10T13:06:18Z

We want to change ::new() to take no parameters and produce a pool that
is as large as possible while also being inline because that is the
constructor that Rust Binder actually needs.

However, to avoid complications in examples, we still need the current
constructor. So rename it to with_capacity(), which is the idiomatic
Rust name for this kind constructor.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
---
rust/kernel/id_pool.rs | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/rust/kernel/id_pool.rs b/rust/kernel/id_pool.rs
index a41a3404213ca92d53b14c80101afff6ac8c416e..5942f678db015e902fa482eb64c38512a468e449 100644
--- a/rust/kernel/id_pool.rs
+++ b/rust/kernel/id_pool.rs
@@ -28,7 +28,7 @@
/// use kernel::alloc::{AllocError, flags::GFP_KERNEL};
/// use kernel::id_pool::IdPool;
///
-/// let mut pool = IdPool::new(64, GFP_KERNEL)?;
+/// let mut pool = IdPool::with_capacity(64, GFP_KERNEL)?;
/// for i in 0..64 {
/// assert_eq!(i, pool.acquire_next_id(i).ok_or(ENOSPC)?);
/// }
@@ -95,14 +95,14 @@ pub fn realloc(&self, flags: Flags) -> Result<PoolResizer, AllocError> {
}

impl IdPool {
- /// Constructs a new [`IdPool`].
+ /// Constructs a new [`IdPool`] with space for a specific number of bits.
///
- /// A capacity below [`BITS_PER_LONG`] is adjusted to
- /// [`BITS_PER_LONG`].
+ /// A capacity below [`NO_ALLOC_MAX_LEN`] is adjusted to
+ /// [`NO_ALLOC_MAX_LEN`].
///
- /// [`BITS_PER_LONG`]: srctree/include/asm-generic/bitsperlong.h
+ /// [`NO_ALLOC_MAX_LEN`]: BitmapVec::NO_ALLOC_MAX_LEN
#[inline]
- pub fn new(num_ids: usize, flags: Flags) -> Result<Self, AllocError> {
+ pub fn with_capacity(num_ids: usize, flags: Flags) -> Result<Self, AllocError> {
let num_ids = core::cmp::max(num_ids, BITS_PER_LONG);
let map = BitmapVec::new(num_ids, flags)?;
Ok(Self { map })
@@ -126,7 +126,7 @@ pub fn capacity(&self) -> usize {
/// use kernel::alloc::{AllocError, flags::GFP_KERNEL};
/// use kernel::id_pool::{ReallocRequest, IdPool};
///
- /// let mut pool = IdPool::new(1024, GFP_KERNEL)?;
+ /// let mut pool = IdPool::with_capacity(1024, GFP_KERNEL)?;
/// let alloc_request = pool.shrink_request().ok_or(AllocError)?;
/// let resizer = alloc_request.realloc(GFP_KERNEL)?;
/// pool.shrink(resizer);

--
2.51.2.1041.gc1ab5b90ca-goog