Re: [PATCH v6 07/28] btrfs: disable fallocate in HMZONED mode

Josef Bacik
2019-12-13T20:39:19Z

On 12/12/19 11:08 PM, Naohiro Aota wrote:
> fallocate() is implemented by reserving actual extent instead of
> reservations. This can result in exposing the sequential write constraint
> of host-managed zoned block devices to the application, which would break
> the POSIX semantic for the fallocated file. To avoid this, report
> fallocate() as not supported when in HMZONED mode for now.
>
> In the future, we may be able to implement "in-memory" fallocate() in
> HMZONED mode by utilizing space_info->bytes_may_use or so.
>
> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>

Reviewed-by: Josef Bacik <josef@toxicpanda.com>

Thanks,

Josef