[libvirt] [PATCH] qemu: Don't fail if physical size can't be updated in qemuDomainGetBlockInfo

[Peter Krempa]

Since commit c5f6151390 qemuDomainBlockInfo tries to update the
"physical" storage size for all network storage and not only block
devices.

Since the storage driver APIs to do this are not implemented for certain
storage types (RBD, iSCSI, ...) the code would fail to retrieve any data
since the failure of qemuDomainStorageUpdatePhysical is fatal.

Since it's desired to return data even if the total size can't be
updated we need to ignore errors from that fucntion and return plausible
data.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1442344
---

Notes:
    This function will require more fixing though. This is just a bandaid to
    remove the regression. I'll post other patches as follow up later.

 src/qemu/qemu_driver.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index e39de625d..8ff242597 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -11553,10 +11553,12 @@ qemuDomainGetBlockInfo(virDomainPtr dom,
         if (info->allocation == 0)
             info->allocation = entry->physical;

-        if (qemuDomainStorageUpdatePhysical(driver, cfg, vm, disk->src) < 0)
-            goto endjob;
-
-        info->physical = disk->src->physical;
+        if (qemuDomainStorageUpdatePhysical(driver, cfg, vm, disk->src) == 0) {
+            info->physical = disk->src->physical;
+        } else {
+            virResetLastError();
+            info->physical = entry->physical;
+        }
     } else {
         info->physical = entry->physical;
     }
-- 
2.12.2