[PATCH 2/5] virtio_blk: remove the broken zone revalidation support

Christoph Hellwig
2023-12-17T16:54:15Z

virtblk_revalidate_zones is called unconditionally from
virtblk_config_changed_work from the virtio config_changed callback.

virtblk_revalidate_zones is a bit odd in that it re-clears the zoned
state for host aware or non-zoned devices, which isn't needed unless the
zoned mode changed - but a zone mode change to a host managed model isn't
handled at all, and virtio_blk also doesn't handle any other config
change except for a capacity change is handled (and even if it was
the upper layers above virtio_blk wouldn't handle it very well).

But even the useful case of a size change that would add or remove
zones isn't handled properly as blk_revalidate_disk_zones expects the
device capacity to cover all zones, but the capacity is only updated
after virtblk_revalidate_zones.

As this code appears to be entirely untested and is getting in the way
remove it for now, but it can be readded in a fixed version with
proper test coverage if needed.

Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices")
Fixes: f1ba4e674feb ("virtio-blk: fix to match virtio spec")
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/block/virtio_blk.c | 26 --------------------------
1 file changed, 26 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index aeead732a24dc9..a28f1687066bb4 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -722,27 +722,6 @@ static int virtblk_report_zones(struct gendisk *disk, sector_t sector,
return ret;
}

-static void virtblk_revalidate_zones(struct virtio_blk *vblk)
-{
- u8 model;
-
- virtio_cread(vblk->vdev, struct virtio_blk_config,
- zoned.model, &model);
- switch (model) {
- default:
- dev_err(&vblk->vdev->dev, "unknown zone model %d\n", model);
- fallthrough;
- case VIRTIO_BLK_Z_NONE:
- case VIRTIO_BLK_Z_HA:
- disk_set_zoned(vblk->disk, BLK_ZONED_NONE);
- return;
- case VIRTIO_BLK_Z_HM:
- WARN_ON_ONCE(!vblk->zone_sectors);
- if (!blk_revalidate_disk_zones(vblk->disk, NULL))
- set_capacity_and_notify(vblk->disk, 0);
- }
-}
-
static int virtblk_probe_zoned_device(struct virtio_device *vdev,
struct virtio_blk *vblk,
struct request_queue *q)
@@ -823,10 +802,6 @@ static int virtblk_probe_zoned_device(struct virtio_device *vdev,
*/
#define virtblk_report_zones NULL

-static inline void virtblk_revalidate_zones(struct virtio_blk *vblk)
-{
-}
-
static inline int virtblk_probe_zoned_device(struct virtio_device *vdev,
struct virtio_blk *vblk, struct request_queue *q)
{
@@ -982,7 +957,6 @@ static void virtblk_config_changed_work(struct work_struct *work)
struct virtio_blk *vblk =
container_of(work, struct virtio_blk, config_work);

- virtblk_revalidate_zones(vblk);
virtblk_update_capacity(vblk, true);
}

--
2.39.2