Solved using this artikel: [GUIDE] Windows Previous Versions and Samba (Btrfs - Atomic COW - Volume Shadow Copy)
How to reproduce a working configuration on Fedora22
1) Create BTRFS subvolume
mount /dev/sda5 /mnt #your BTRFS partition btrfs subvolume create /mnt/share brtfs subvolume create /mnt/share/.snapshots umount /mnt
2) edit fstab (or mount manually according)
UUID= /share brtfs subvol=share 0 0 UUID= /share/.snapshots btrfs subvol=share/.snapshots 0 0
3) Create Samba share
[btrfs] path = /share vfs objects = shadow_copy2 shadow:format = @GMT_%Y.%m.%d-%H.%M.%S shadow:sort = desc shadow:snapdir = .snapshots
4) Create a readonly snapshot
brtfs subvolume snapshot -r /share /share/.snapshots/@GMT_`date +%Y.%m.%d-%H.%M.%S`
5) How to delete a snapshot
btrfs subvolume delete /share/.snapshots/@GMT_2015.07.31-14.01.20