[libvirt] [PATCH RFC 36/40] qemu: domain: Track backup job data in the status XML

[Peter Krempa]

Store the data of a backup job along with the index counter for new
backup jobs in the status XML. Currently we will support only one
backup job and thus there's no necessity to add arrays of jobs.

Signed-off-by: Peter Krempa <pkrempa at redhat.com>
---
 src/qemu/qemu_domain.c | 72 ++++++++++++++++++++++++++++++++++++++++++
 src/qemu/qemu_domain.h |  4 +++
 2 files changed, 76 insertions(+)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index d5a2ddaa8c..738f06bc5b 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -61,6 +61,7 @@
 #include "locking/domain_lock.h"
 #include "virdomainsnapshotobjlist.h"
 #include "virdomaincheckpointobjlist.h"
+#include "backup_conf.h"

 #ifdef MAJOR_IN_MKDEV
 # include <sys/mkdev.h>
@@ -2108,6 +2109,8 @@ qemuDomainObjPrivateAlloc(void *opaque)
     priv->migMaxBandwidth = QEMU_DOMAIN_MIG_BANDWIDTH_MAX;
     priv->driver = opaque;

+    priv->backupnextid = 1;
+
     return priv;

  error:
@@ -2177,6 +2180,10 @@ qemuDomainObjPrivateDataClear(qemuDomainObjPrivatePtr priv)

     virHashRemoveAll(priv->blockjobs);
     virHashRemoveAll(priv->dbusVMStates);
+
+    virDomainBackupDefFree(priv->backup);
+    priv->backup = NULL;
+    priv->backupnextid = 1;
 }


@@ -2593,6 +2600,29 @@ qemuDomainObjPrivateXMLFormatBlockjobs(virBufferPtr buf,
 }


+static int
+qemuDomainObjPrivateXMLFormatBackups(virBufferPtr buf,
+                                     virDomainObjPtr vm)
+{
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    g_auto(virBuffer) attrBuf = VIR_BUFFER_INITIALIZER;
+    g_auto(virBuffer) childBuf = VIR_BUFFER_INITIALIZER;
+
+    virBufferSetChildIndent(&childBuf, buf);
+
+    if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_INCREMENTAL_BACKUP))
+        return 0;
+
+    virBufferAsprintf(&attrBuf, " nextid='%llu'", priv->backupnextid);
+
+    if (priv->backup &&
+        virDomainBackupDefFormat(&childBuf, priv->backup, true) < 0)
+        return -1;
+
+    return virXMLFormatElement(buf, "backups", &attrBuf, &childBuf);
+}
+
+
 void
 qemuDomainObjPrivateXMLFormatAllowReboot(virBufferPtr buf,
                                          virTristateBool allowReboot)
@@ -2907,6 +2937,9 @@ qemuDomainObjPrivateXMLFormat(virBufferPtr buf,
     if (qemuDomainObjPrivateXMLFormatSlirp(buf, vm) < 0)
         return -1;

+    if (qemuDomainObjPrivateXMLFormatBackups(buf, vm) < 0)
+        return -1;
+
     return 0;
 }

@@ -3272,6 +3305,42 @@ qemuDomainObjPrivateXMLParseBlockjobs(virDomainObjPtr vm,
 }


+static int
+qemuDomainObjPrivateXMLParseBackups(qemuDomainObjPrivatePtr priv,
+                                    xmlXPathContextPtr ctxt)
+{
+    g_autofree xmlNodePtr *nodes = NULL;
+    ssize_t nnodes = 0;
+
+    priv->backupnextid = 1;
+    if (virXPathULongLong("string(./backups/@nextid)", ctxt,
+                          &priv->backupnextid) == -2) {
+        virReportError(VIR_ERR_XML_ERROR, "%s",
+                       _("failed to parse next backup job id"));
+        return -1;
+    }
+
+    if ((nnodes = virXPathNodeSet("./backups/domainbackup", ctxt, &nodes)) < 0)
+        return -1;
+
+    if (nnodes > 1) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("only one backup job is supported"));
+        return -1;
+    }
+
+    if (nnodes == 0)
+        return 0;
+
+    if (!(priv->backup = virDomainBackupDefParseNode(ctxt->doc, nodes[0],
+                                                     priv->driver->xmlopt,
+                                                     VIR_DOMAIN_BACKUP_PARSE_INTERNAL)))
+        return -1;
+
+    return 0;
+}
+
+
 int
 qemuDomainObjPrivateXMLParseAllowReboot(xmlXPathContextPtr ctxt,
                                         virTristateBool *allowReboot)
@@ -3696,6 +3765,9 @@ qemuDomainObjPrivateXMLParse(xmlXPathContextPtr ctxt,
     if (qemuDomainObjPrivateXMLParseBlockjobs(vm, priv, ctxt) < 0)
         goto error;

+    if (qemuDomainObjPrivateXMLParseBackups(priv, ctxt) < 0)
+        goto error;
+
     qemuDomainStorageIdReset(priv);
     if (virXPathULongLong("string(./nodename/@index)", ctxt,
                           &priv->nodenameindex) == -2) {
diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index 5b3d84cea7..765801895c 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -396,6 +396,10 @@ struct _qemuDomainObjPrivate {

     virHashTablePtr dbusVMStates;
     bool disableSlirp;
+
+    /* Running backup jobs. */
+    unsigned long long backupnextid;
+    virDomainBackupDefPtr backup;
 };

 #define QEMU_DOMAIN_PRIVATE(vm) \
-- 
2.21.0