Here are two more Exadata scripts for listing the end-to-end ASM<->Exadata disk topology from V$ASM_ views and from V$CELL_CONFIG. These scripts see both the ASM level layout and the storage cell-level disk topology.
The exadisktopo.sql script shows all disks starting from the ASM diskgroup layer, going deeper and deeper all the way to the OS disk device level in the storage cells. It uses outer joins, so will show celldisks even if there are no corresponding grid disks allocated on them (or if there are no ASM disks using them). It also shows the Flash cards used as flash cache, thus there are no ASM disks on them usually.
The output should be self-explanatory, you just read the data from left to right (from ASM diskgroup to ASM disk to Grid Disk level etc), the more rightwards you scroll, the “deeper” you go in the Exadata IO stack layers. Warning, lots of wide output coming :)