[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-block] [Qemu-devel] [PATCH 2/2] qapi: Allow blockdev-add for N
Daniel P. Berrange
Re: [Qemu-block] [Qemu-devel] [PATCH 2/2] qapi: Allow blockdev-add for NBD
Wed, 3 Feb 2016 17:06:09 +0000
On Wed, Feb 03, 2016 at 05:33:16PM +0100, Max Reitz wrote:
> We have to introduce a new object (BlockdevOptionsNbd) for several
> - Neither of InetSocketAddress nor UnixSocketAddress alone is
> sufficient, because both are supported
> - We cannot use SocketAddress because NBD does not support an fd,
> and because it is not a flat union which BlockdevOptionsNbd is
With my patch series that converts NBD to use QIOChannel, all the
entry points for client & server *do* take a SocketAddress struct
to provide address info. So internally the code does in fact allow
use of an FD, if there were a way to specify it a the QAPI level...
> - We cannot use a flat union of InetSocketAddress and
> UnixSocketAddress because we would need some kind of discriminator
> which we do not have; we could inline the UnixSocketAddress as a
> string and then make it an 'alternate' type instead of a union, but
> this will not work either, because:
> - InetSocketAddress itself is not suitable for NBD because the port is
> not optional (which it is for NBD) and because it offers more options
> (like choosing between ipv4 and ipv6) which NBD does not support.
The *should* support ipv4 and ipv6 options for NBD. We should also make
the port optional in the SocketAddress struct - I tried to do that previously
but my patch was flawed, but we should revisit this.
So IMHO all the things you list above are reasons *for* using SocketAddress
and not re-inventing it poorly with explicit host + port fields.
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
[Qemu-block] [PATCH 1/2] block/nbd: Reject port parameter without host, Max Reitz, 2016/02/03