top left   top right

64-bit DASD DIAG

This is a patch to the kernel that adds the ability to use the DASD DIAG discipline in a 64-bit environment.  It seems that everyone recommends the use of the DIAG discipline for swap, but us folks running 64-bit were left out as z/VM doesn't (yet) support DIAG x'250' in a 64-bit world.

This version "fixes" the problem of the label not being recognized.  Since the label information contains the offset to the reserved portion of the CMS disk, the disk structures would be overlaid due to the way the partition was setup.  In addition, I've attempted to reorganize and strip out unnecessary code.  It also contains a couple more minor kernel fixes.

To enable it (and the DIAG discipline itself), select the options in the "S/390 block device drivers" kernel configuration section.

Though I have not tested it, the patch should also be usable in a 31-bit environment so the additional block size support can be utilized.

DO NOT USE in a production environment without extensive testing.  While it "seems" to work just fine, I may have missed something so make sure you read the this page.





Change History:

Date Change
2003-07-21 Fixed CMS label recognition
2003-07-18 Adding ability to use all DIAG x'250' supported block sizes
2003-07-14 Fixed random oops when using with a regular file system (not just swap)
2003-07-13 Initial distribution
bottom left   bottom right