System, method, and program for determining if write data overlaps source data within a data migration scheme

A system for migrating source data to target data, comprising:

• a source storage location;
• a target storage location;
• a memory;
• and
• circuitry that communicates with the source and target storage locations and the memory, wherein the circuitry implements a migration manager and performs operations, the operations comprising:
• using, by the migration manager, a map indicating source data to migrate to target data;
• receiving write requests to write application data to source data not yet migrated to the target data;
• generating information for the write requests indicating the source data to which the application data is written;
• writing the application data for the write requests to the source data;
• issuing, by the migration manager, migration requests to migrate source data to target data indicated in the map as not yet migrated;
• receiving, by a migration function, a migration request from the migration manager to migrate source data indicated in the map as not yet migrated to target data as part of a migration operation to mirror source data to target data;
• returning, by the migration function, indication to retry the migration request to the migration manager in response to the migration request and in response to determining that the requested source data to migrate as part of the migration request overlaps source data indicated in the generated information for one of the write requests;
• and
• returning, by the migration function, indication to retry the migration request to migrate to the migration manager in response to migrating the source data to the target data for the migration request and in response to determining that the migrated source data overlaps source data indicated in the generated information for one of the write requests.

An article of manufacture comprising at least one of a hardware device including hardware logic and computer readable storage including code operable for performing operations to migrate source data to target data, wherein the code includes a migration manager and causes operations to be performed, the operations comprising:

• using, by the migration manager, a map indicating source data to migrate to target data;
• receiving write requests to write application data to source data not yet migrated to the target data;
• generating information for the write requests indicating the source data to which the application data is written;
• writing the application data for the write requests to the source data;
• issuing, by the migration manager, migration requests to migrate source data to target data indicated in the map as not yet migrated;
• receiving, by a migration function, a migration request from the migration manager to migrate source data indicated in the map as not yet migrated to target data as part of a migration operation to mirror source data to target data;
• returning, by the migration function, indication to retry the migration request to the migration manager in response to the migration request and in response to determining that the requested source data to migrate as part of the migration request overlaps source data indicated in the generated information for one of the write requests;
• and
• returning, by the migration function, indication to retry the migration request to migrate to the migration manager in response to migrating the source data to the target data for the migration request and in response to determining that the migrated source data overlaps source data indicated in the generated information for one of the write requests.