Re: [libvirt] [PATCH 4/6] conf: Add support for blkiotune group_name option

On Mon, Oct 31, 2016 at 05:23:00PM -0400, John Ferlan wrote: > Modify _virDomainBlockIoTuneInfo and rng schema to support the group_name > option for iotune throttling. Document the new value. > > Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; > --- > docs/formatdomain.html.in | 11 ++++ > docs/schemas/domaincommon.rng | 5 ++ > src/conf/domain_conf.c | 9 ++++ > .../qemuxml2argv-blkdeviotune-group-num.xml | 61 > ++++++++++++++++++++++ > .../qemuxml2xmlout-blkdeviotune-group-num.xml | 1 + > tests/qemuxml2xmltest.c | 1 + > 6 files changed, 88 insertions(+) > create mode 100644 > tests/qemuxml2argvdata/qemuxml2argv-blkdeviotune-group-num.xml > create mode 120000 > tests/qemuxml2xmloutdata/qemuxml2xmlout-blkdeviotune-group-num.xml > > diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in > index c70377b..8d30737 100644 > --- a/docs/formatdomain.html.in > +++ b/docs/formatdomain.html.in > @@ -2622,6 +2622,17 @@ > <span class="since">Throughput limits since 1.2.11 and > QEMU 1.7</span> > </p> > </dd> > + <dt><code>group_name</code></dt> > + <dd>The optional <code>group_name</code> provides the cability > + to share I/O throttling quota between multiple drives. This > + prevents end-users from circumventing a hosting provider's > + throttling policy by splitting 1 large drive in N small > drives > + and getting N times the normal throttling quota. Any name > may > + be used. I'm really scared when I see that "any name may be used", I would rather put a sensible set of restrictions here that we can remove later, but let's go with "any name" for now. [...]

> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c > index f41a783..8ad52d0 100644 > --- a/src/conf/domain_conf.c > +++ b/src/conf/domain_conf.c > @@ -20416,6 +20420,11 @@ virDomainDiskDefFormat(virBufferPtr buf, > def->blkdeviotune.size_iops_sec); > } > > + if (def->blkdeviotune.group_name) { > + virBufferAsprintf(buf, "<group_name>%s</group_name>\n", > + def->blkdeviotune.group_name); Because of that you need to escape it here. Case that requires this would be nice to have in tests.