Hello,
>But at least we can determine if samba is utilizing btrfs quota by:
># btrfs qgroup show -prce <btrfs mount point>
btrfs qgroup show -prce /srv/DataPool1/Dokumente/Hendrik/
ERROR: can't list qgroups: quotas not enabled
>>  May 12 09:34:06 homeserver smbd[4116]:   sys_path_to_bdev() failed for
>>  path [.]!
>
>Not sure what the sys_path_to_bdev() is, but since btrfs has
>multi-device support, bdev from btrfs doesn't make much sense compared
>to other single device filesystem.
I read, that the same problem exists for ZFS.
>Would you please describe the impact of above messages?
>Does it cause samba mount read/write failure or something else?
>
I have not yet noticed any impact (Syslog is at 26MB now). I am also not 
using quota. Thus, I would not notice an impact due to quota problems.
Greetings,
Hendrik