System for on-line disk system configuration

A computer readable medium executing on a data processing system including an I/O subsystem, the computer readable medium including program instructions for performing the steps of:

• configuring one or more storage devices having divided as containers;
• storing partition information copied from the storage devices in a partition table;
• processing I/O requests directed to the containers with one or more container drivers;
• providing a device switch table that contains pointers to entry points of container drivers;
• providing a container array table that contains pointers to data structures used by the container drivers, wherein each entry in the container array table has an associated entry in the device switch table;
• reconfiguring, by an initiation of a reconfiguration process, the storage devices into containers while the data processing system is performing other services, including (a) blocking all new I/O requests to the I/O subsystem in response an initiation of a reconfiguration process, (b) completing processing of the I/O requests previously received by the I/O subsystem, (c) unblocking the new I/O requests and (d) executing the new I/O requests after being unblocked by the means for unblocking based upon entry points that are the same as entry points to which the blocked I/O requests pointed prior to the initiation of the reconfiguration process;
• and
• changing the entries of the device switch table, the container array table, and the partition table to reflect the reconfiguration.