[Libguestfs] [PATCH v4 0/3] v2v: Add -o rhv-upload output mode.

[Richard W.M. Jones]

It has to be said it would be really convenient to have a 'zero'
and/or 'trim' method of some sort.

qemu-img tries hard to trim the whole disk before using it.
Unfortunately it does this in different ways across RHEL 7 and
upstream.  With upstream I managed a workaround based on ignoring any
zero requests which arrive before the first write.  However it's not
so easy to do this for RHEL 7's qemu which is issuing mixed writes and
zeroes in different orders.

How hard would it be to implement a special https request in imageio
for zeroing (better still, either zeroing or trimming) a range of
bytes?

Rich.

-- 
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