Writing and reading data sets to and from cloud storage for legacy mainframe applications

A computer program product, the computer program product being tangibly embodied on a non-transitory computer-readable medium and comprising instructions that, when executed by at least one computing device, are configured to cause the at least one computing device to:

• determine an allocating of a dataset request by an application executed by an operating system (OS) of the mainframe computer;
• intercept, at a virtual device routine executing in place of a mount/unmount routine of the OS, a mount request issued by the OS in response to the allocating of the dataset request by the application;
• determine whether the dataset request should be processed at the virtual device routine or provided to the mount/unmount routine, based on whether the dataset request is designated for implementation using a simulated tape having a simulated volume within cloud storage or using a physical tape;
• simulate, at the virtual device routine and in response to the mount request and to the determining that the dataset request is designated for implementation using the simulated tape having the simulated volume within the cloud storage, a mounting of the simulated tape;
• receive a first exit call to a cloud agent module to prepare for dataset write by the application to the simulated volume of the simulated tape, via the cloud agent module;
• open, by the cloud agent module, a dataset on the simulated volume within the cloud storage;
• intercept a first data block and a second data block written by the application to the OS;
• and
• send, by the cloud agent module, the first data block and the second data block in a data chunk to the cloud storage.

A system comprising:

• at least one memory including instructions;
• and
• at least one processor that is operably coupled to the at least one memory and that is arranged and configured to execute instructions that, when executed, cause the at least one processor to:
• determine an allocating of a dataset request by an application executed by an operating system (OS) of the mainframe computer;
• intercept, at a virtual device routine executing in place of a mount/unmount routine of the OS, a mount request issued by the OS in response to the allocating of the dataset request by the application;
• determine whether the dataset request should be processed at the virtual device routine or provided to the mount/unmount routine, based on whether the dataset request is designated for implementation using a simulated tape having a simulated volume within cloud storage or using a physical tape;
• simulate, at the virtual device routine and in response to the mount request and to the determining that the dataset request is designated for implementation using the simulated tape having the simulated volume within the cloud storage, a mounting of the simulated tape;
• receive a first exit call to a cloud agent module to prepare for dataset write by the application to the simulated volume of the simulated tape, via the cloud agent module;
• open, by the cloud agent module, a dataset on the simulated volume within the cloud storage;
• intercept a first data block and a second data block written by the application to the OS;
• and
• send, by the cloud agent module, the first data block and the second data block in a data chunk to the cloud storage.