In an IRF "Daisy-Chain", each member is connected to at least one other member, 2 members are only connected to one neighbour.
In an IRF "Ring", every member is connected to 2 other members.
Essentially, a "Ring" means there are 2 paths off every single switch.
In a 2-chassis IRF, if there is a single connection between the 2 members, it's a "Daisy-chain". If there are two connections, then assuming each member has 2 IRF ports, it's a "Ring".
Your IRF should be a "Ring", for redundancy.
I haven't played with IRF for ages - I can't remember: can you put multiple switchports into the same IRF port?