Example embodiments respond to input/output (I/O) requests to a storage stack having a hierarchy of layers. In one such embodiment, responsive to an I/O request for data from a higher layer of the stack to a lower of the stack in hierarchy order, a first help response is generated at the lower layer and sent to the higher layer to recover the data. In turn, at the higher layer, it is determined whether a recover mechanism can fulfill the I/O request and, if not, a second help response is generated and sent to a next higher layer in the hierarchy. At the next higher layer, it is determined whether a recovery mechanism can fulfill the I/O request and, if not, a third help response is generated and sent to an even next higher layer in the hierarchy.