diff options
| author | Johannes Thumshirn <johannes.thumshirn@wdc.com> | 2025-12-10 03:10:37 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-12-09 22:35:54 -0700 |
| commit | 2c38ec934ddfe2d35c813edea2674356bea0fabe (patch) | |
| tree | 459a3eaf9778cb3944672e57acfe49e82a5d60c0 | |
| parent | 59e25ef2b413c72da6686d431e7759302cfccafa (diff) | |
block: fix cached zone reports on devices with native zone append
When mounting a btrfs file system on virtio-blk which supports native
Zone Append there has been a WARN triggering in btrfs' space management
code.
Further looking into btrfs' zoned statistics uncovered the filesystem
expecting the zones to be used, but the write pointers being 0:
# cat /sys/fs/btrfs/8eabd2e7-3294-4f9e-9b58-7e64135c8bf4/zoned_stats
active block-groups: 4
reclaimable: 0
unused: 0
need reclaim: false
data relocation block-group: 1342177280
active zones:
start: 1073741824, wp: 0 used: 0, reserved: 0, unusable: 0
start: 1342177280, wp: 0 used: 0, reserved: 0, unusable: 0
start: 1610612736, wp: 0 used: 16384, reserved: 0, unusable: 18446744073709535232
start: 1879048192, wp: 0 used: 131072, reserved: 0, unusable: 18446744073709420544
Looking at the blkzone report output for the zone in question
(1610612736) the write pointer on the device moved, but the filesystem
did not see a change on the write pointer:
# blkzone report -c 1 -o 0x300000 /dev/vda
start: 0x000300000, len 0x080000, cap 0x080000, wptr 0x000040 reset:0 non-seq:0, zcond: 2(oi) [type: 2(SEQ_WRITE_REQUIRED)]
The zone write pointer is 0, because btrfs is using the cached version
of blkdev_report_zones() and as virtio-blk is supporting native zone
append, but blkdev_revalidate_zones() does not initialize the zone write
plugs in this case.
Not skipping the revalidate of sequential zones in
blkdev_revalidate_zones() callchain fixes this issue.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Fixes: a6aa36e957a1 ("block: Remove zone write plugs when handling native zone append writes")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/blk-zoned.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/block/blk-zoned.c b/block/blk-zoned.c index 394d8d74bba9..1c54678fae6b 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -2100,7 +2100,7 @@ static int blk_revalidate_seq_zone(struct blk_zone *zone, unsigned int idx, * we have a zone write plug for such zone if the device has a zone * write plug hash table. */ - if (!queue_emulates_zone_append(disk->queue) || !disk->zone_wplugs_hash) + if (!disk->zone_wplugs_hash) return 0; wp_offset = disk_zone_wplug_sync_wp_offset(disk, zone); |