Re: [Qemu-devel] [PATCH v3 00/19] nbd: add qemu-nbd --list

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

12.01.2019 20:57, Eric Blake wrote:
> I got tired of debugging whether a server was advertising the
> correct things during negotiation by inspecting the trace
> logs of qemu-io as client - not to mention that without SOME
> sort of client tracing particular commands, we can't easily
> regression test the server for correct behavior.  The final
> straw was at KVM Forum, when Nir asked me to make sure there
> was a way to easily determine if an NBD server is exposing what
> we really want (and fixing x-dirty-bitmap to behave saner fell
> out as a result of answering that question).
> 
> I note that upstream NBD has 'nbd-client -l $host' for querying
> just export names (with no quoting, so you have to know that
> a blank line means the default export), but it wasn't powerful
> enough, so I implemented 'qemu-nbd -L' to document everything.
> Upstream NBD has separate 'nbd-client' and 'nbd-server' binaries,
> while we only have 'qemu-nbd' (which is normally just a server,
> but 'qemu-nbd -c' also operates a second thread as a client).
> Our other uses of qemu as NBD client are for consuming a block
> device (as in qemu-io, qemu-img, or a drive to qemu) - but those
> binaries are less suited to something so specific to the NBD
> protocol.
> 
> Bonus: As a result of my work on this series, nbdkit now supports
> NBD_OPT_INFO (my interoperability testing between server
> implementations has been paying off, both at fixing server bugs,
> and at making this code more reliable across difference in valid
> servers).
> 
> Also available at:
> https://repo.or.cz/qemu/ericb.git qemu-nbd-list-v2
> 
> Based-on: <20181221093529.23855-1-jsnow@redhat.com>
> [jsnow: 0/11 bitmaps: remove x- prefix from QMP api]
> Based-on: <20190111163519.11457-1-philmd@redhat.com>
> [philmd: qemu-nbd: Rename 'exp' variable clashing with math::exp() symbol]
> Based-on: <20190111194720.15671-1-eblake@redhat.com>
> [eblake: 0/8 Promote x-nbd-server-add-bitmap to stable]
> 
> Since v2:
> - Several patches merged already
> - 3 new patches based on audit of off_t vs. strtol
> - rebase patches on top of other changes, such as qemu-nbd --bitmap
> - address various review comments [Vladimir, Rich]
> - drop patch 12/22
> 
> 001/19:[0020] [FC] 'maint: Allow for EXAMPLES in texi2pod'
> 002/19:[0030] [FC] 'qemu-nbd: Enhance man page'

Strange, but I don't have 02 in my mailbox..


-- 
Best regards,
Vladimir