Management of multiple software images with relocation of boot blocks

A computer program product comprising:

• a computer readable storage medium having computer readable code embodied therewith, the computer readable program code comprising:
• computer readable program code configured for:
• managing multiple software images in a data processing entity that includes a mass memory with a plurality of memory locations, each of the memory locations having a corresponding memory address within the mass memory, each of the software images including a plurality of memory blocks, each of the memory blocks having a corresponding image address within the software image, wherein the managing includes:
• storing at least part of the memory blocks of each of the software images into a corresponding image portion of the mass memory, each of the memory blocks being stored into the memory location having the memory address equal to the corresponding image address plus an offset of the image portion within the mass memory;
• selecting a current software image stored in a current image;
• relocating the memory blocks stored in boot locations of the current software image to a relocation portion of the mass memory, the boot locations of the current software image being the memory locations having the memory addresses equal to the image addresses of boot blocks of the current software image including the memory blocks thereof required to boot the data processing entity up to load an access function adapted to access the current software image;
• copying the boot blocks of the current software image into the corresponding boot locations;
• booting the data processing entity from the boot blocks of the current software image in the corresponding boot locations thereby loading the access function;
• and
• serving each request to access a selected memory block of the current software image by the access function, the access function accessing the selected memory block in the memory location having the memory address equal to the corresponding image address plus the offset of the current image portion.

A computer system comprising:

• a processor configured for:
• managing multiple software images in a data processing entity that includes a mass memory with a plurality of memory locations, each of the memory locations having a corresponding memory address within the mass memory, each of the software images including a plurality of memory blocks, each of the memory blocks having a corresponding image address within the software image, wherein the managing includes:
• storing at least part of the memory blocks of each of the software images into a corresponding image portion of the mass memory, each of the memory blocks being stored into the memory location having the memory address equal to the corresponding image address plus an offset of the image portion within the mass memory;
• selecting a current software image stored in a current image;
• relocating the memory blocks stored in boot locations of the current software image to a relocation portion of the mass memory, the boot locations of the current software image being the memory locations having the memory addresses equal to the image addresses of boot blocks of the current software image including the memory blocks thereof required to boot the data processing entity up to load an access function adapted to access the current software image;
• copying the boot blocks of the current software image into the corresponding boot locations;
• booting the data processing entity from the boot blocks of the current software image in the corresponding boot locations thereby loading the access function;
• and
• serving each request to access a selected memory block of the current software image by the access function, the access function accessing the selected memory block in the memory location having the memory address equal to the corresponding image address plus the offset of the current image portion.