[PATCH 23/79] block: rust: change sector type from usize to u64

From: Andreas Hindborg

Date: Sun Feb 15 2026 - 18:56:16 EST


Change the `sector()` and `sectors()` methods in `Request` to return
`u64` and `u32` respectively instead of `usize`. This matches the
underlying kernel types.

Update rnull driver to handle the new sector types with appropriate
casting throughout the read, write, and discard operations.

Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
---
drivers/block/rnull/rnull.rs | 49 +++++++++++++++++++++--------------------
rust/kernel/block/mq/request.rs | 8 +++----
2 files changed, 29 insertions(+), 28 deletions(-)

diff --git a/drivers/block/rnull/rnull.rs b/drivers/block/rnull/rnull.rs
index 9a301b06fc5e0..b0008e2f9c398 100644
--- a/drivers/block/rnull/rnull.rs
+++ b/drivers/block/rnull/rnull.rs
@@ -225,7 +225,7 @@ fn new(options: NullBlkOptions<'_>) -> Result<GenDisk<Self>> {
irq_mode,
completion_time,
memory_backed,
- block_size: block_size as usize,
+ block_size: block_size.into(),
}),
GFP_KERNEL,
)?;
@@ -246,54 +246,55 @@ fn new(options: NullBlkOptions<'_>) -> Result<GenDisk<Self>> {
}

#[inline(always)]
- fn write(tree: &Tree, mut sector: usize, mut segment: Segment<'_>) -> Result {
+ fn write(tree: &Tree, mut sector: u64, mut segment: Segment<'_>) -> Result {
while !segment.is_empty() {
let page = NullBlockPage::new()?;
let mut tree = tree.lock();

let page_idx = sector >> block::PAGE_SECTORS_SHIFT;

- let page = if let Some(page) = tree.get_mut(page_idx) {
+ let page = if let Some(page) = tree.get_mut(page_idx as usize) {
page
} else {
- tree.store(page_idx, page, GFP_NOIO)?;
- tree.get_mut(page_idx).unwrap()
+ tree.store(page_idx as usize, page, GFP_NOIO)?;
+ tree.get_mut(page_idx as usize).unwrap()
};

page.set_occupied(sector);
- let page_offset = (sector & block::SECTOR_MASK as usize) << block::SECTOR_SHIFT;
- sector +=
- segment.copy_to_page(page.page.get_pin_mut(), page_offset) >> block::SECTOR_SHIFT;
+ let page_offset = (sector & u64::from(block::SECTOR_MASK)) << block::SECTOR_SHIFT;
+ sector += segment.copy_to_page(page.page.get_pin_mut(), page_offset as usize) as u64
+ >> block::SECTOR_SHIFT;
}
Ok(())
}

#[inline(always)]
- fn read(tree: &Tree, mut sector: usize, mut segment: Segment<'_>) -> Result {
+ fn read(tree: &Tree, mut sector: u64, mut segment: Segment<'_>) -> Result {
let tree = tree.lock();

while !segment.is_empty() {
let idx = sector >> block::PAGE_SECTORS_SHIFT;

- if let Some(page) = tree.get(idx) {
- let page_offset = (sector & block::SECTOR_MASK as usize) << block::SECTOR_SHIFT;
- sector += segment.copy_from_page(&page.page, page_offset) >> block::SECTOR_SHIFT;
+ if let Some(page) = tree.get(idx as usize) {
+ let page_offset = (sector & u64::from(block::SECTOR_MASK)) << block::SECTOR_SHIFT;
+ sector += segment.copy_from_page(&page.page, page_offset as usize) as u64
+ >> block::SECTOR_SHIFT;
} else {
- sector += segment.zero_page() >> block::SECTOR_SHIFT;
+ sector += segment.zero_page() as u64 >> block::SECTOR_SHIFT;
}
}

Ok(())
}

- fn discard(tree: &Tree, mut sector: usize, sectors: usize, block_size: usize) -> Result {
+ fn discard(tree: &Tree, mut sector: u64, sectors: u64, block_size: u64) -> Result {
let mut remaining_bytes = sectors << SECTOR_SHIFT;
let mut tree = tree.lock();

while remaining_bytes > 0 {
let page_idx = sector >> block::PAGE_SECTORS_SHIFT;
let mut remove = false;
- if let Some(page) = tree.get_mut(page_idx) {
+ if let Some(page) = tree.get_mut(page_idx as usize) {
page.set_free(sector);
if page.is_empty() {
remove = true;
@@ -301,7 +302,7 @@ fn discard(tree: &Tree, mut sector: usize, sectors: usize, block_size: usize) ->
}

if remove {
- drop(tree.remove(page_idx))
+ drop(tree.remove(page_idx as usize))
}

let processed = remaining_bytes.min(block_size);
@@ -316,7 +317,7 @@ fn discard(tree: &Tree, mut sector: usize, sectors: usize, block_size: usize) ->
fn transfer(
command: bindings::req_op,
tree: &Tree,
- sector: usize,
+ sector: u64,
segment: Segment<'_>,
) -> Result {
match command {
@@ -346,13 +347,13 @@ fn new() -> Result<KBox<Self>> {
)?)
}

- fn set_occupied(&mut self, sector: usize) {
- let idx = sector & SECTOR_MASK as usize;
+ fn set_occupied(&mut self, sector: u64) {
+ let idx = sector & u64::from(SECTOR_MASK);
self.status |= 1 << idx;
}

- fn set_free(&mut self, sector: usize) {
- let idx = sector & SECTOR_MASK as usize;
+ fn set_free(&mut self, sector: u64) {
+ let idx = sector & u64::from(SECTOR_MASK);
self.status &= !(1 << idx);
}

@@ -371,7 +372,7 @@ struct QueueData {
irq_mode: IRQMode,
completion_time: Delta,
memory_backed: bool,
- block_size: usize,
+ block_size: u64,
}

#[pin_data]
@@ -422,14 +423,14 @@ fn queue_rq(
let mut sector = rq.sector();

if command == bindings::req_op_REQ_OP_DISCARD {
- Self::discard(tree, sector, rq.sectors(), queue_data.block_size)?;
+ Self::discard(tree, sector, rq.sectors().into(), queue_data.block_size)?;
} else {
for bio in rq.bio_iter_mut() {
let segment_iter = bio.segment_iter();
for segment in segment_iter {
let length = segment.len();
Self::transfer(command, tree, sector, segment)?;
- sector += length as usize >> block::SECTOR_SHIFT;
+ sector += u64::from(length) >> block::SECTOR_SHIFT;
}
}
}
diff --git a/rust/kernel/block/mq/request.rs b/rust/kernel/block/mq/request.rs
index 9d11ae5651983..8fe7e126c522a 100644
--- a/rust/kernel/block/mq/request.rs
+++ b/rust/kernel/block/mq/request.rs
@@ -139,16 +139,16 @@ pub fn bio_iter_mut<'a>(self: &'a mut Owned<Self>) -> BioIterator<'a> {

/// Get the target sector for the request.
#[inline(always)]
- pub fn sector(&self) -> usize {
+ pub fn sector(&self) -> u64 {
// SAFETY: By type invariant of `Self`, `self.0` is valid and live.
- unsafe { (*self.0.get()).__sector as usize }
+ unsafe { (*self.0.get()).__sector }
}

/// Get the size of the request in number of sectors.
#[inline(always)]
- pub fn sectors(&self) -> usize {
+ pub fn sectors(&self) -> u32 {
// SAFETY: By type invariant of `Self`, `self.0` is valid and live.
- (unsafe { (*self.0.get()).__data_len as usize }) >> crate::block::SECTOR_SHIFT
+ (unsafe { (*self.0.get()).__data_len }) >> crate::block::SECTOR_SHIFT
}

/// Return a pointer to the [`RequestDataWrapper`] stored in the private area

--
2.51.2