[PATCH 79/79] block: rnull: add zone offline and readonly configfs files

From: Andreas Hindborg

Date: Sun Feb 15 2026 - 18:46:17 EST


Add configfs attributes for managing zone states in the rnull zoned
block device emulation. The `zone_offline` and `zone_readonly`
attributes allow setting specific zones to offline or read-only states,
which is useful for testing how applications handle degraded zones.

Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
---
drivers/block/rnull/configfs.rs | 80 +++++++++++++++++++++++++++++++++++
drivers/block/rnull/disk_storage.rs | 59 +++++++++++++-------------
drivers/block/rnull/rnull.rs | 2 +-
drivers/block/rnull/zoned.rs | 83 ++++++++++++++++++++++++++-----------
4 files changed, 168 insertions(+), 56 deletions(-)

diff --git a/drivers/block/rnull/configfs.rs b/drivers/block/rnull/configfs.rs
index 395da68d96dc6..1c0d95ded7e9f 100644
--- a/drivers/block/rnull/configfs.rs
+++ b/drivers/block/rnull/configfs.rs
@@ -125,6 +125,8 @@ fn make_group(
max_sectors: 29,
virt_boundary: 30,
shared_tag_bitmap: 31,
+ zone_offline: 32,
+ zone_readonly: 33,
],
};

@@ -639,3 +641,81 @@ fn store(this: &DeviceConfig, page: &[u8]) -> Result {
configfs_simple_field!(DeviceConfig, 29, max_sectors, u32);
configfs_simple_bool_field!(DeviceConfig, 30, virt_boundary);
configfs_simple_bool_field!(DeviceConfig, 31, shared_tag_bitmap);
+
+#[cfg(CONFIG_BLK_DEV_ZONED)]
+fn set_zone_condition(
+ this: &DeviceConfig,
+ sector: u64,
+ cb: impl FnOnce(
+ &crate::zoned::ZoneOptions,
+ &DiskStorage,
+ &mut crate::zoned::ZoneDescriptor,
+ ) -> Result,
+) -> Result {
+ use crate::zoned::ZoneType;
+ let data_guard = this.data.lock();
+ let null_disk = data_guard.disk.as_ref().ok_or(EBUSY)?.queue_data();
+ let storage = &null_disk.storage;
+ let zone_options = &null_disk.zoned;
+ zone_options.enabled.then_some(()).ok_or(EINVAL)?;
+ let mut zone = zone_options.zone(sector)?.lock();
+
+ if zone.kind == ZoneType::Conventional {
+ return Err(EINVAL);
+ }
+
+ cb(zone_options, storage, &mut zone)
+}
+
+#[cfg(CONFIG_BLK_DEV_ZONED)]
+configfs_attribute!(
+ DeviceConfig,
+ 32,
+ show: |_this, _page| Ok(0),
+ store: |this,page| {
+ let text = core::str::from_utf8(page)?.trim();
+ let sector = text.parse().map_err(|_| EINVAL)?;
+
+ set_zone_condition(this, sector, |zone_options, storage, zone| {
+ zone_options.offline_zone(storage, zone)
+ })?;
+ Ok(())
+ },
+);
+
+#[cfg(CONFIG_BLK_DEV_ZONED)]
+configfs_attribute!(
+ DeviceConfig,
+ 33,
+ show: |_this, _page| Ok(0),
+ store: |this,page| {
+ let text = core::str::from_utf8(page)?.trim();
+ let sector = text.parse().map_err(|_| EINVAL)?;
+
+ set_zone_condition(this, sector, |zone_options, storage, zone| {
+ zone_options.read_only_zone(storage, zone)
+ })?;
+
+ Ok(())
+ },
+);
+
+#[cfg(not(CONFIG_BLK_DEV_ZONED))]
+configfs_attribute!(
+ DeviceConfig,
+ 32,
+ show: |this, page| {Ok(0)},
+ store: |this,page| {
+ Err(ENOTSUPP)
+ },
+);
+
+#[cfg(not(CONFIG_BLK_DEV_ZONED))]
+configfs_attribute!(
+ DeviceConfig,
+ 33,
+ show: |this, page| {Ok(0)},
+ store: |this,page| {
+ Err(ENOTSUPP)
+ },
+);
diff --git a/drivers/block/rnull/disk_storage.rs b/drivers/block/rnull/disk_storage.rs
index d9f2703957fc0..802e9534ca2a5 100644
--- a/drivers/block/rnull/disk_storage.rs
+++ b/drivers/block/rnull/disk_storage.rs
@@ -65,27 +65,45 @@ pub(crate) fn lock(&self) -> SpinLockGuard<'_, Pin<KBox<TreeContainer>>> {
self.trees.lock()
}

- pub(crate) fn discard(
- &self,
- hw_data: &Pin<&SpinLock<HwQueueContext>>,
- mut sector: u64,
- sectors: u32,
- ) {
- let mut tree_guard = self.lock();
- let mut hw_data_guard = hw_data.lock();
-
- let mut access = self.access(&mut tree_guard, &mut hw_data_guard, None);
+ pub(crate) fn discard(&self, mut sector: u64, sectors: u32) {
+ let tree_guard = self.lock();
+ let mut cache_guard = tree_guard.cache_tree.lock();
+ let mut disk_guard = tree_guard.cache_tree.lock();

let mut remaining_bytes = sectors_to_bytes(sectors);

while remaining_bytes > 0 {
- access.free_sector(sector);
+ self.free_sector(&mut cache_guard, &mut disk_guard, sector);
let processed = remaining_bytes.min(self.block_size);
sector += Into::<u64>::into(bytes_to_sectors(processed));
remaining_bytes -= processed;
}
}

+ fn free_sector_tree(tree_access: &mut xarray::Guard<'_, TreeNode>, sector: u64) {
+ let index = DiskStorageAccess::to_index(sector);
+ if let Some(page) = tree_access.get_mut(index) {
+ page.set_free(sector);
+
+ if page.is_empty() {
+ tree_access.remove(index);
+ }
+ }
+ }
+
+ pub(crate) fn free_sector<'a>(
+ &self,
+ cache_guard: &mut xarray::Guard<'a, TreeNode>,
+ disk_guard: &mut xarray::Guard<'a, TreeNode>,
+ sector: u64,
+ ) {
+ if self.cache_size > 0 {
+ Self::free_sector_tree(cache_guard, sector);
+ }
+
+ Self::free_sector_tree(disk_guard, sector);
+ }
+
pub(crate) fn flush(&self, hw_data: &Pin<&SpinLock<HwQueueContext>>) {
let mut tree_guard = self.lock();
let mut hw_data_guard = hw_data.lock();
@@ -262,25 +280,6 @@ pub(crate) fn get_read_page(&self, sector: u64) -> Option<&NullBlockPage> {
self.disk_guard.get(index)
}
}
-
- fn free_sector_tree(tree_access: &mut xarray::Guard<'_, TreeNode>, sector: u64) {
- let index = Self::to_index(sector);
- if let Some(page) = tree_access.get_mut(index) {
- page.set_free(sector);
-
- if page.is_empty() {
- tree_access.remove(index);
- }
- }
- }
-
- pub(crate) fn free_sector(&mut self, sector: u64) {
- if self.disk_storage.cache_size > 0 {
- Self::free_sector_tree(&mut self.cache_guard, sector);
- }
-
- Self::free_sector_tree(&mut self.disk_guard, sector);
- }
}

type Tree = XArray<TreeNode>;
diff --git a/drivers/block/rnull/rnull.rs b/drivers/block/rnull/rnull.rs
index 5bf965908ef63..91f8636d74cca 100644
--- a/drivers/block/rnull/rnull.rs
+++ b/drivers/block/rnull/rnull.rs
@@ -739,7 +739,7 @@ fn handle_regular_command(

if self.memory_backed {
if rq.command() == mq::Command::Discard {
- self.storage.discard(hw_data, rq.sector(), sectors);
+ self.storage.discard(rq.sector(), sectors);
} else {
self.transfer(hw_data, rq, rq.command(), sectors)?;
}
diff --git a/drivers/block/rnull/zoned.rs b/drivers/block/rnull/zoned.rs
index 0f15f4cc4e5c3..3b8ebf5449a8d 100644
--- a/drivers/block/rnull/zoned.rs
+++ b/drivers/block/rnull/zoned.rs
@@ -178,7 +178,7 @@ pub(crate) fn handle_zoned_command(
match rq.command() {
ZoneAppend | Write => self.zoned_write(hw_data, rq)?,
ZoneReset | ZoneResetAll | ZoneOpen | ZoneClose | ZoneFinish => {
- self.zone_management(hw_data, rq)?
+ self.zone_management(rq)?
}
_ => self.zoned_read(hw_data, rq)?,
}
@@ -186,18 +186,14 @@ pub(crate) fn handle_zoned_command(
Ok(())
}

- fn zone_management(
- &self,
- hw_data: &Pin<&SpinLock<HwQueueContext>>,
- rq: &mut Owned<mq::Request<Self>>,
- ) -> Result {
+ fn zone_management(&self, rq: &mut Owned<mq::Request<Self>>) -> Result {
if rq.command() == mq::Command::ZoneResetAll {
for zone in self.zoned.zones_iter() {
let mut zone = zone.lock();
use ZoneCondition::*;
match zone.condition {
Empty | ReadOnly | Offline => continue,
- _ => self.zoned.reset_zone(&self.storage, hw_data, &mut zone)?,
+ _ => self.zoned.reset_zone(&self.storage, &mut zone)?,
}
}

@@ -213,10 +209,10 @@ fn zone_management(

use mq::Command::*;
match rq.command() {
- ZoneOpen => self.zoned.open_zone(&mut zone, rq.sector()),
+ ZoneOpen => self.zoned.open_zone(&mut zone),
ZoneClose => self.zoned.close_zone(&mut zone),
- ZoneReset => self.zoned.reset_zone(&self.storage, hw_data, &mut zone),
- ZoneFinish => self.zoned.finish_zone(&mut zone, rq.sector()),
+ ZoneReset => self.zoned.reset_zone(&self.storage, &mut zone),
+ ZoneFinish => self.zoned.finish_zone(&mut zone),
_ => Err(EIO),
}
}
@@ -282,7 +278,7 @@ fn zoned_write(
if self.zoned.use_accounting() {
let mut accounting = self.zoned.accounting.lock();
self.zoned
- .check_zone_resources(&mut accounting, &mut zone, rq.sector())?;
+ .check_zone_resources(&mut accounting, &mut zone)?;

if zone.condition == ZoneCondition::Closed {
accounting.closed -= 1;
@@ -365,7 +361,7 @@ fn zone_no(&self, sector: u64) -> usize {
(sector >> self.size_sectors.ilog2()) as usize
}

- fn zone(&self, sector: u64) -> Result<&Mutex<ZoneDescriptor>> {
+ pub(crate) fn zone(&self, sector: u64) -> Result<&Mutex<ZoneDescriptor>> {
self.zones.get(self.zone_no(sector)).ok_or(EINVAL)
}

@@ -418,7 +414,7 @@ fn try_close_implicit_open_zone(&self, accounting: &mut ZoneAccounting, sector:
Err(EINVAL)
}

- fn open_zone(&self, zone: &mut ZoneDescriptor, sector: u64) -> Result {
+ fn open_zone(&self, zone: &mut ZoneDescriptor) -> Result {
if zone.kind == ZoneType::Conventional {
return Err(EINVAL);
}
@@ -434,13 +430,13 @@ fn open_zone(&self, zone: &mut ZoneDescriptor, sector: u64) -> Result {
let mut accounting = self.accounting.lock();
match zone.condition {
Empty => {
- self.check_zone_resources(&mut accounting, zone, sector)?;
+ self.check_zone_resources(&mut accounting, zone)?;
}
ImplicitOpen => {
accounting.implicit_open -= 1;
}
Closed => {
- self.check_zone_resources(&mut accounting, zone, sector)?;
+ self.check_zone_resources(&mut accounting, zone)?;
accounting.closed -= 1;
}
_ => (),
@@ -457,14 +453,13 @@ fn check_zone_resources(
&self,
accounting: &mut ZoneAccounting,
zone: &mut ZoneDescriptor,
- sector: u64,
) -> Result {
match zone.condition {
ZoneCondition::Empty => {
self.check_active_zones(accounting)?;
- self.check_open_zones(accounting, sector)
+ self.check_open_zones(accounting, zone.start_sector)
}
- ZoneCondition::Closed => self.check_open_zones(accounting, sector),
+ ZoneCondition::Closed => self.check_open_zones(accounting, zone.start_sector),
_ => Err(EIO),
}
}
@@ -533,7 +528,7 @@ fn close_zone(&self, zone: &mut ZoneDescriptor) -> Result {
Ok(())
}

- fn finish_zone(&self, zone: &mut ZoneDescriptor, sector: u64) -> Result {
+ fn finish_zone(&self, zone: &mut ZoneDescriptor) -> Result {
if zone.kind == ZoneType::Conventional {
return Err(EINVAL);
}
@@ -545,12 +540,12 @@ fn finish_zone(&self, zone: &mut ZoneDescriptor, sector: u64) -> Result {
match zone.condition {
Full => return Ok(()),
Empty => {
- self.check_zone_resources(&mut accounting, zone, sector)?;
+ self.check_zone_resources(&mut accounting, zone)?;
}
ImplicitOpen => accounting.implicit_open -= 1,
ExplicitOpen => accounting.explicit_open -= 1,
Closed => {
- self.check_zone_resources(&mut accounting, zone, sector)?;
+ self.check_zone_resources(&mut accounting, zone)?;
accounting.closed -= 1;
}
_ => return Err(EIO),
@@ -566,7 +561,6 @@ fn finish_zone(&self, zone: &mut ZoneDescriptor, sector: u64) -> Result {
fn reset_zone(
&self,
storage: &crate::disk_storage::DiskStorage,
- hw_data: &Pin<&SpinLock<HwQueueContext>>,
zone: &mut ZoneDescriptor,
) -> Result {
if zone.kind == ZoneType::Conventional {
@@ -589,16 +583,55 @@ fn reset_zone(
zone.condition = ZoneCondition::Empty;
zone.write_pointer = zone.start_sector;

- storage.discard(hw_data, zone.start_sector, zone.size_sectors);
+ storage.discard(zone.start_sector, zone.size_sectors);
+
+ Ok(())
+ }
+
+ fn set_zone_condition(
+ &self,
+ storage: &crate::disk_storage::DiskStorage,
+ zone: &mut ZoneDescriptor,
+ condition: ZoneCondition,
+ ) -> Result {
+ if zone.condition == condition {
+ zone.condition = ZoneCondition::Empty;
+ zone.write_pointer = zone.start_sector;
+ storage.discard(zone.start_sector, zone.size_sectors);
+ } else {
+ if matches!(
+ zone.condition,
+ ZoneCondition::ReadOnly | ZoneCondition::Offline
+ ) {
+ self.finish_zone(zone)?;
+ }

+ zone.condition = ZoneCondition::Offline;
+ zone.write_pointer = u64::MAX;
+ }
Ok(())
}
+ pub(crate) fn offline_zone(
+ &self,
+ storage: &crate::disk_storage::DiskStorage,
+ zone: &mut ZoneDescriptor,
+ ) -> Result {
+ self.set_zone_condition(storage, zone, ZoneCondition::Offline)
+ }
+
+ pub(crate) fn read_only_zone(
+ &self,
+ storage: &crate::disk_storage::DiskStorage,
+ zone: &mut ZoneDescriptor,
+ ) -> Result {
+ self.set_zone_condition(storage, zone, ZoneCondition::ReadOnly)
+ }
}

pub(crate) struct ZoneDescriptor {
start_sector: u64,
size_sectors: u32,
- kind: ZoneType,
+ pub(crate) kind: ZoneType,
capacity_sectors: u32,
write_pointer: u64,
condition: ZoneCondition,
@@ -626,7 +659,7 @@ fn check_bounds_read(&self, sector: u64, sectors: u32) -> Result {

#[derive(Copy, Clone, PartialEq, Eq, Debug)]
#[repr(u32)]
-enum ZoneType {
+pub(crate) enum ZoneType {
Conventional = bindings::blk_zone_type_BLK_ZONE_TYPE_CONVENTIONAL,
SequentialWriteRequired = bindings::blk_zone_type_BLK_ZONE_TYPE_SEQWRITE_REQ,
#[expect(dead_code)]

--
2.51.2