[Libguestfs] [PATCH libnbd v2 0/3] copy: Use preferred block size for copying

[Richard W.M. Jones]

This is not really an evolution of the previous patch set, I started
almost from scratch, but for reference version 1 was here:

https://listman.redhat.com/archives/libguestfs/2022-June/029301.html

This version does appear to work, all tests pass, and I ran the nbdkit
test suite as well (which uses nbdcopy in a bunch of places) and that
passes also.

Note that patch 3 is a generic fix of a test which was previously
broken, but now that larger requests are being made by default, it
breaks much more often.

Rich.