On Wed, Mar 17, 2021 at 05:57:31PM +0900, Johannes Thumshirn wrote:
> In btrfs_submit_direct() there's a WAN_ON_ONCE() that will trigger if
> we're submitting a DIO write on a zoned filesystem but are not using
> REQ_OP_ZONE_APPEND to submit the IO to the block device.
>
> This is a left over from a previous version where btrfs_dio_iomap_begin()
> didn't use btrfs_use_zone_append() to check for sequential write only
> zones.
I can't identify the patch where this got changed. I've landed on
544d24f9de73 ("btrfs: zoned: enable zone append writing for direct IO")
but that adds the btrfs_use_zone_append, the append flag and also the
warning.
