Creating the range list

The range list is a storage area containing up to 16 entries. Each entry consists of 2 words as follows:

First word: The starting virtual address of the storage range that the system is to make eligible to be assigned to a subspace. The starting address must be on a megabyte boundary. A megabyte is 1,048,576 bytes long.
Second word: The number of pages (4096 bytes), beginning at the address in the first word, that are to be made eligible to be assigned to a subspace. The number must be a multiple of 256.

The range list must be addressable in the caller's primary address space. Each range must reside in a single subpool.

You might not be able to obtain all of the subspace storage required by your application programs in a single STORAGE macro request. If you cannot, add an entry to the range list for each storage request. The STORAGE macro returns the number of bytes of storage obtained in GPR 0. The second word of the range list entry requires the number of pages obtained. To convert the number of bytes into the number pages, divide the number of bytes returned in GPR 0 by 4096. Store the quotient into the second word of the range list entry. Store the contents of GPR 1 into the first word of the range list entry.