[Libguestfs] [PATCH v2v] vddk: Use blocksize filter to split very large requests

Predictably this makes no difference to the current code since nbdcopy is using 256K requests. I will do some real testing when Nir pushes his change here: https://listman.redhat.com/archives/libguestfs/2022-February/msg00188.html Nir - do you want to actually increase that back to 8M? In theory (untested) it should be safe provided it's combined with something like this patch. Rich.