Patent ID: 7290102

Claim:
A computer program product comprising logic instructions stored on a computer-readable medium which, when executed by a processor, configure the processor to create a point in time copy of a successor logical disk by executing operations comprising: creating a PLDMC for a predecessor logical disk; creating an LMAP for the predecessor logical disk; populating the LMAP for the predecessor logical disk with one or more RSD pointers from an LMAP associated with the successor logical disk; creating an L2MAP for the predecessor logical disk; populating the L2MAP for the predecessor logical disk with one or more pointers to one or more predecessor LMAP records; setting one or more share bits in the one or more LMAPs for the predecessor logical disk and the successor logical disk to indicate that the user data is being shared; and setting one or more share bits in the successor PLDMC to indicate that the data is being shared.