[libvirt] [PATCH 1/1] Add a simple pool type for multipath devices

[Dave Allan]

Daniel Veillard wrote:
> On Tue, Jul 21, 2009 at 05:25:37PM -0400, David Allan wrote:
>> This pool type contains volumes for the multipath devices that are present on the host.  It does not (yet) support any sort of multipath configuration, so that aspect of system administration must still be done at host build time.
> [...]
>> +if test "$with_storage_mpath" = "check"; then
>> +   with_storage_mpath=yes
>> +
>> +   AC_DEFINE_UNQUOTED([WITH_STORAGE_MPATH], 1,
>> +     [whether mpath backend for storage driver is enabled])
>> +fi
>> +AM_CONDITIONAL([WITH_STORAGE_MPATH], [test "$with_storage_mpath" = "yes"])
>> +
>> +if test "$with_storage_mpath" = "yes"; then
>> +   DEVMAPPER_REQUIRED=0.0
>> +   DEVMAPPER_CFLAGS=
>> +   DEVMAPPER_LIBS=
>> +   PKG_CHECK_MODULES(DEVMAPPER, devmapper >= $DEVMAPPER_REQUIRED,
>> +    [], [
>> +    AC_MSG_ERROR(
>> +    [You must install device-mapper-devel >= $DEVMAPPER_REQUIRED to compile libvirt])
>> +    ])
>> +fi
>> +AC_SUBST([DEVMAPPER_CFLAGS])
>> +AC_SUBST([DEVMAPPER_LIBS])
> 
>   Hum, the way I read this is that f you give no specific option to
> configure, check turns into a with_storage_mpath" = "yes" and then if
> device-mapper-devel is not available configure fails, while I would
> expect check to not fail in that case and switch with_storage_mpath to
> no , I afraid this can be confusing, or I'm the one confused :-)

Hmm...yes, I was afraid I hadn't gotten the build stuff quite right. 
I'm getting familiar with how it all works, but your advice on how to do 
this would be very welcome.  Basically all I want is for libdevmapper to 
be pulled into the compile/link if the user requests a build with 
multipath support.

> [...]
>> +++ b/src/storage_backend_mpath.c
>> @@ -0,0 +1,344 @@
>> +/*
>> + * storage_backend_mpath.c: storage backend for multipath handling
>> + *
>> + * Copyright (C) 2007-2008 Red Hat, Inc.
>> + * Copyright (C) 2007-2008 Daniel P. Berrange
> [...]
>> + * Author: Daniel P. Berrange <berrange redhat com>
> 
>   Hum, really ? please update :-) or clarify ! and extend to 2009

Damn C&P...thanks for catching that.

> 
> [...]
>> +++ b/src/storage_backend_mpath.h
>> @@ -0,0 +1,31 @@
>> +/*
>> + * storage_backend_scsi.h: storage backend for SCSI handling
>> + *
>> + * Copyright (C) 2007-2008 Red Hat, Inc.
>> + * Copyright (C) 2007-2008 Daniel P. Berrange
> [...]
>> + * Author: Daniel P. Berrange <berrange redhat com>
>> + */
> 
>   To be fixed too including name and description

Indeed.  Thanks; I'll make those changes in the next revision.

Dave