[libvirt] [PATCH] Add support for multiple serial ports into the Xen driver

[Eric Blake]

On 02/17/2011 02:37 AM, Michal Novotny wrote:
> Eric, thanks for reply but I'm having some issues now...
> 
> I've pulled libvirt sources from upstream and I'm unable to compile it
> since it keeps saying following:
> 
>   CCLD   libvirt_parthelper
> ./.libs/libvirt_util.a(libvirt_util_la-util.o): In function
> `virFileOperationNoFork':
> /home/mig/Work/virt-related/libvirt/src/util/util.c:1363: undefined
> reference to `rpl_open'

Huh.  rpl_open is a gnulib replacement for open(); I'm not sure why
gnulib thinks open() needs replacing on Linux (unless it is trying to
provide O_CLOEXEC support for older kernels).  Was this an incremental
build, where you had already built before updating to the latest
libvirt.git, and just typed 'make'?

Can you try 'rm gnulib/lib/fcntl.h', then 'make', to see if it clears up
the issue?  If it doesn't, then maybe you'll have to resort to a
full-blown clean checkout.

> 
> Unfortunately I was unable to find definition of 'rpl_open' function
> using git grep so I don't really know what to do there. Some bug or do I
> miss something?

It's defined by gnulib, which is copied into place from the gnulib.git
submodule during ./autogen.sh (and not under libvirt.git's control).
Even then, it only exists in the replacement <fcntl.h> header provided
by gnulib when gnulib thinks that open() isn't up to snuff with POSIX
requirements.

> Basically I don't know what you mean by this. Also, when I was defining
> XMLs I saw that the console node copies the first serial node however
> how to define it if first serial node is just none?
> 
> I mean the XML is like:
> 
> <serial type='dev'>
> <source path='/dev/ttyS0'/>
> <target port='0'/>
> </serial>
> <serial type='dev'>
> <source path='/dev/ttyS1'/>
> <target port='1'/>
> </serial>
> <console type='dev'>
> <source path='/dev/ttyS0'/>
> <target port='0'/>
> </console>
> 
> But what should the XML part be for case of first serial device to be
> none ?

I think the key is the <target port='1'/>.  You don't need any
placeholder in the XML for a missing port 0, but you do need it in the
xm format where port is implied by position.  That is:

<devices>
  <serial type='dev'>
    <source path='/dev/ttyS1'/>
    <target port='1'/>
  </serial>
</devices>

should be sufficient XML to mark that you want to use multi-serial xen
support, and that you are explicitly leaving virtual port 0 unoccupied
and plugging in your one serial device into virtual port 1; mapping to:

serial = [ "none", "/dev/ttyS1" ]

in the xm file.  The sexpr rationale should be the same.

-- 
Eric Blake   eblake at redhat.com    +1-801-349-2682
Libvirt virtualization library http://libvirt.org

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 619 bytes
Desc: OpenPGP digital signature
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20110217/284fc749/attachment-0001.sig>