[PATCH] qemu: Expose disk serial in virDomainGetGuestInfo()

[Michal Privoznik <mprivozn@xxxxxxxxxx>]

When querying guest info via virDomainGetGuestInfo() the
'guest-get-disks' agent command is called. It may report disk
serial number which we parse, but never report nor use for
anything else.

As it turns out, it may help management application find matching
disk in their internals.

Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx>
---
 src/libvirt-domain.c   |  1 +
 src/qemu/qemu_driver.c | 19 ++++++++++++++-----
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
index 83ff7df9fe..1c244da650 100644
--- a/src/libvirt-domain.c
+++ b/src/libvirt-domain.c
@@ -12561,6 +12561,7 @@ virDomainSetVcpu(virDomainPtr domain,
  *                      hold the list of PVs, for LUKS encrypted volume this will
  *                      contain the disk where the volume is placed. (Linux)
  *      "disk.<num>.dependency.<num>.name" - a dependency
+ *      "disk.<num>.serial" - disk serial number
  *      "disk.<num>.alias" - the device alias of the disk (e.g. sda)
  *      "disk.<num>.guest_alias" - optional alias assigned to the disk, on Linux
  *                      this is a name assigned by device mapper
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 90b5477f00..88ee9e5d5e 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -19951,15 +19951,24 @@ qemuAgentDiskInfoFormatParams(qemuAgentDiskInfo **info,
         }
 
         if (info[i]->address) {
+            qemuAgentDiskAddress *address = info[i]->address;
             virDomainDiskDef *diskdef = NULL;
 
+            if (address->serial) {
+                g_snprintf(param_name, VIR_TYPED_PARAM_FIELD_LENGTH,
+                           "disk.%zu.serial", i);
+                if (virTypedParamsAddString(params, nparams, maxparams,
+                                            param_name, address->serial) < 0)
+                    return;
+            }
+
             /* match the disk to the target in the vm definition */
             diskdef = virDomainDiskByAddress(vmdef,
-                                             &info[i]->address->pci_controller,
-                                             info[i]->address->ccw_addr,
-                                             info[i]->address->bus,
-                                             info[i]->address->target,
-                                             info[i]->address->unit);
+                                             &address->pci_controller,
+                                             address->ccw_addr,
+                                             address->bus,
+                                             address->target,
+                                             address->unit);
             if (diskdef) {
                 g_snprintf(param_name, VIR_TYPED_PARAM_FIELD_LENGTH,
                            "disk.%zu.alias", i);
-- 
2.26.3