Re: [libvirt] [PATCH] disk: Fixup error handling path for devmapper when part_separator='yes'

ping? Tks - John On 11/17/2016 09:55 AM, John Ferlan wrote: > https://bugzilla.redhat.com/show_bug.cgi?id=1346566 > > If libvirt_parthelper is erroneously told to append the partition > separator 'p' onto the generated output for a disk pool using device > mapper that has 'user_friendly_names' set to true, then the error > recovery path will fail to find volume resulting in the pool being > in an unusable state. > > So, augment the documentation to provide the better hint that the > part_separator='yes' should be set when user_friendly_names are not > being used. Additionally, once we're in the error path where the > returned name doesn't match the expected partition name try to see > if the reason is because the 'p' was erroneosly added. If so alter > the about to be removed vol->target.path so that the DiskDeleteVol > code can find the partition that was created and remove it. > > Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; > --- > docs/formatstorage.html.in | 5 ++++- > src/storage/storage_backend_disk.c | 23 +++++++++++++++++++++++ > 2 files changed, 27 insertions(+), 1 deletion(-) > > diff --git a/docs/formatstorage.html.in b/docs/formatstorage.html.in > index ed1f0d1..7690114 100644 > --- a/docs/formatstorage.html.in > +++ b/docs/formatstorage.html.in > @@ -138,7 +138,10 @@ > causes libvirt to attempt to generate and find target volume path's > using a "p" separator. The default algorithm used by device mapper > is to add the "p" separator only when the source device path ends > - with a number. > + with a number; however, it's possible to configure the devmapper > + device to not use 'user_friendly_names' thus creating partitions > + with the "p" separator even when the device source path does not > + end with a number. > <span class="since">Since 1.3.1</span></p></dd> > <dt><code>dir</code></dt> > <dd>Provides the source for pools backed by directories (pool > diff --git a/src/storage/storage_backend_disk.c b/src/storage/storage_backend_disk.c > index 666ad03..07a04f1 100644 > --- a/src/storage/storage_backend_disk.c > +++ b/src/storage/storage_backend_disk.c > @@ -95,6 +95,29 @@ virStorageBackendDiskMakeDataVol(virStoragePoolObjPtr pool, > virReportError(VIR_ERR_INVALID_ARG, > _("invalid partition name '%s', expected '%s'"), > vol->name, partname); > + > + /* Let's see if we by chance parthelper created a name that won't be > + * found later when we try to delete. We tell parthelper to add a 'p' > + * to the output via the part_separator flag, but if devmapper has > + * user_friendly_names set, the creation won't happen that way, thus > + * our deletion will fail because the name we generated is wrong. > + * Check for our conditions and see if the generated name is the > + * same as StablePath returns and has the 'p' in it */ > + if (pool->def->source.devices[0].part_separator == > + VIR_TRISTATE_BOOL_YES && > + !virIsDevMapperDevice(vol->target.path) && > + STREQ(groups[0], vol->target.path) && > + (tmp = strrchr(groups[0], 'p'))) { > + > + /* If we remove the 'p' from groups[0] and the resulting > + * device is a devmapper device, then we know parthelper > + * was told to create the wrong name based on the results. > + * So just remove the 'p' from the vol->target.path too. */ > + memmove(tmp, tmp + 1, strlen(tmp)); > + if (virIsDevMapperDevice(groups[0]) && > + (tmp = strrchr(vol->target.path, 'p'))) > + memmove(tmp, tmp + 1, strlen(tmp)); > + } > return -1; > } > > -- libvir-list mailing list libvir-list(a)redhat.com https://www.redhat.com/mailman/listinfo/libvir-list