Re: [Qemu-devel] [RFC] introduce a dynamic library to expose qemu block API

[Wenchao Xia]

于 2012-7-13 19:33, Paolo Bonzini 写道:
> Il 13/07/2012 11:51, Paolo Bonzini ha scritto:
> > Il 13/07/2012 11:16, Stefan Hajnoczi ha scritto:
> > > > "Working around the QEMU block layer license" is not a goal per se,
> > > > especially because you haven't a) assessed _what_ is the GPL code that
> > > > the library would use; b) told us why the library should not be under
> > > > the GPL.
> > > >
> > > > Please design first according to the functionality you want to
> > > > implement, then think about the implementation.
> > >
> > > Licensing is one headache but the real challenge is that the QEMU block
> > > layer relies on the QEMU main loop and a bunch of other architecture.
> >
> > It doesn't really, not on Windows which has no AIO for example.  That's
> > why I suggested:
> >
> > - assessing what code is GPL and what are the dependencies on it
>
> So I tried trimming down the list of files needed to compile
> qemu tools, and here is a list:
  Really thanks for the investigation, I paid quite sometime to dig out
which license is compatible to LGPL, this have sorted it out.
  The coroutine and structure inside is quite a challenge. What about
provide the library first in nbd + sync access, and waiting for the
library employer response? If it is good to use, then replace implement
code to native qemu block layer code, change code's license, while keep
API unchanged.


> Easy to relicense to LGPLv2+:
> block/raw.c                     none (GPLv2+: Red Hat, IBM)
> error.c                         LGPLv2 (Red Hat, IBM, Stefan Weil)
> iov.c                           GPLv2 (Red Hat, SuSE/Hannes Reinecke, Michael 
> Tokarev)
> module.c                        GPLv2 (Red Hat, IBM, Blue Swirl)
> qemu-error.c                    GPLv2+ (Red Hat, Blue Swirl, IBM)
> trace/control.c                 GPLv2 (Lluis Vilanova)
> trace/default.c                 GPLv2 (Lluis Vilanova)
>
> (I added some people to Cc.  Lluis and Michael, can you also look at
> http://wiki.qemu.org/Relicensing if you're willing to relicense
> your past contributions from GPLv2 to GPLv2+?.  Blue Swirl said
> he'd accept any other GPLv2 or GPLv3 compatible license, which
> should include LGPLv2+).
>
> Harder to relicense to LGPLv2+:
> block/vdi.c                     GPLv2+
>
> "Good" license:
> aes.c                           BSD
> async.c                         BSD
> block.c                         BSD
> block/bochs.c                   BSD
> block/cloop.c                   BSD
> block/cow.c                     BSD
> block/dmg.c                     BSD
> block/parallels.c               BSD
> block/qcow.c                    BSD
> block/qcow2-cache.c             BSD
> block/qcow2-cluster.c           BSD
> block/qcow2-refcount.c          BSD
> block/qcow2-snapshot.c          BSD
> block/qcow2.c                   BSD
> block/qed-check.c               BSD
> block/qed-cluster.c             BSD
> block/qed-gencb.c               BSD
> block/qed-l2-cache.c            BSD
> block/qed-table.c               BSD
> block/qed.c                     BSD
> block/vmdk.c                    BSD
> block/vpc.c                     BSD
> block/vvfat.c                   BSD
> cutils.c                        BSD
> osdep.c                         BSD
> oslib-posix.c                   BSD
> qemu-coroutine-io.c             BSD
> qemu-coroutine-lock.c           BSD
> qemu-option.c                   BSD
> qemu-progress.c                 BSD
> coroutine-ucontext.c            LGPLv2+
> json-lexer.c                    LGPLv2+
> json-parser.c                   LGPLv2+
> json-streamer.c                 LGPLv2+
> qbool.c                         LGPLv2+
> qdict.c                         LGPLv2+
> qemu-coroutine.c                LGPLv2+
> qerror.c                        LGPLv2+
> qfloat.c                        LGPLv2+
> qint.c                          LGPLv2+
> qjson.c                         LGPLv2+
> qlist.c                         LGPLv2+
> qstring.c                       LGPLv2+
>
> Doesn't need to be included in a library:
> qemu-tool.c                     GPLv2
>
> Autogenerated:
> trace.c
>
> Remaining undefined symbols:
> qemu_aio_flush
> qemu_aio_wait
> qemu_free_timer
> qemu_new_timer
> qemu_mod_timer
> qemu_del_timer
> qemu_get_clock_ns
> vm_clock
> + those defined in qemu-tool.c
>
> Paolo


--
Best Regards

Wenchao Xia