[libvirt] [PATCH 5/7] qemu: Wire up PR_MANAGER_STATUS_CHANGED event

[Michal Privoznik]

This event is emitted on the monitor if one of pr-managers lost
connection to its pr-helper process. What libvirt needs to do is
restart the pr-helper process iff it corresponds to managed
pr-manager.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_monitor.c      | 15 +++++++++++++
 src/qemu/qemu_monitor.h      | 11 +++++++++
 src/qemu/qemu_monitor_json.c | 23 +++++++++++++++++++
 src/qemu/qemu_process.c      | 53 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 102 insertions(+)

diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c
index 6ed475ede0..ca95f6f94a 100644
--- a/src/qemu/qemu_monitor.c
+++ b/src/qemu/qemu_monitor.c
@@ -1669,6 +1669,21 @@ qemuMonitorEmitDumpCompleted(qemuMonitorPtr mon,
 }
 
 
+int
+qemuMonitorEmitPRManagerStatusChanged(qemuMonitorPtr mon,
+                                      const char *prManager,
+                                      bool connected)
+{
+    int ret = -1;
+    VIR_DEBUG("mon=%p, prManager='%s', connected=%d", mon, prManager, connected);
+
+    QEMU_MONITOR_CALLBACK(mon, ret, domainPRManagerStatusChanged,
+                          mon->vm, prManager, connected);
+
+    return ret;
+}
+
+
 int
 qemuMonitorSetCapabilities(qemuMonitorPtr mon)
 {
diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h
index b3d62324b4..f1ea0bc541 100644
--- a/src/qemu/qemu_monitor.h
+++ b/src/qemu/qemu_monitor.h
@@ -273,6 +273,12 @@ typedef int (*qemuMonitorDomainDumpCompletedCallback)(qemuMonitorPtr mon,
                                                       const char *error,
                                                       void *opaque);
 
+typedef int (*qemuMonitorDomainPRManagerStatusChangedCallback)(qemuMonitorPtr mon,
+                                                               virDomainObjPtr vm,
+                                                               const char *prManager,
+                                                               bool connected,
+                                                               void *opaque);
+
 typedef struct _qemuMonitorCallbacks qemuMonitorCallbacks;
 typedef qemuMonitorCallbacks *qemuMonitorCallbacksPtr;
 struct _qemuMonitorCallbacks {
@@ -305,6 +311,7 @@ struct _qemuMonitorCallbacks {
     qemuMonitorDomainAcpiOstInfoCallback domainAcpiOstInfo;
     qemuMonitorDomainBlockThresholdCallback domainBlockThreshold;
     qemuMonitorDomainDumpCompletedCallback domainDumpCompleted;
+    qemuMonitorDomainPRManagerStatusChangedCallback domainPRManagerStatusChanged;
 };
 
 char *qemuMonitorEscapeArg(const char *in);
@@ -433,6 +440,10 @@ int qemuMonitorEmitDumpCompleted(qemuMonitorPtr mon,
                                  qemuMonitorDumpStatsPtr stats,
                                  const char *error);
 
+int qemuMonitorEmitPRManagerStatusChanged(qemuMonitorPtr mon,
+                                          const char *prManager,
+                                          bool connected);
+
 int qemuMonitorStartCPUs(qemuMonitorPtr mon);
 int qemuMonitorStopCPUs(qemuMonitorPtr mon);
 
diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index 3e90279b71..03c94cd88b 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -91,6 +91,7 @@ static void qemuMonitorJSONHandleMigrationPass(qemuMonitorPtr mon, virJSONValueP
 static void qemuMonitorJSONHandleAcpiOstInfo(qemuMonitorPtr mon, virJSONValuePtr data);
 static void qemuMonitorJSONHandleBlockThreshold(qemuMonitorPtr mon, virJSONValuePtr data);
 static void qemuMonitorJSONHandleDumpCompleted(qemuMonitorPtr mon, virJSONValuePtr data);
+static void qemuMonitorJSONHandlePRManagerStatusChanged(qemuMonitorPtr mon, virJSONValuePtr data);
 
 typedef struct {
     const char *type;
@@ -113,6 +114,7 @@ static qemuEventHandler eventHandlers[] = {
     { "MIGRATION_PASS", qemuMonitorJSONHandleMigrationPass, },
     { "NIC_RX_FILTER_CHANGED", qemuMonitorJSONHandleNicRxFilterChanged, },
     { "POWERDOWN", qemuMonitorJSONHandlePowerdown, },
+    { "PR_MANAGER_STATUS_CHANGED", qemuMonitorJSONHandlePRManagerStatusChanged, },
     { "RESET", qemuMonitorJSONHandleReset, },
     { "RESUME", qemuMonitorJSONHandleResume, },
     { "RTC_CHANGE", qemuMonitorJSONHandleRTCChange, },
@@ -1297,6 +1299,27 @@ qemuMonitorJSONHandleDumpCompleted(qemuMonitorPtr mon,
 }
 
 
+static void qemuMonitorJSONHandlePRManagerStatusChanged(qemuMonitorPtr mon,
+                                                        virJSONValuePtr data)
+{
+    const char *name;
+    bool connected;
+
+    if (!(name = virJSONValueObjectGetString(data, "id"))) {
+        VIR_WARN("missing pr-manager alias in PR_MANAGER_STATUS_CHANGED event");
+        return;
+    }
+
+    if (virJSONValueObjectGetBoolean(data, "connected", &connected) < 0) {
+        VIR_WARN("missing connected state for %s "
+                 "in PR_MANAGER_STATUS_CHANGED event", name);
+        return;
+    }
+
+    qemuMonitorEmitPRManagerStatusChanged(mon, name, connected);
+}
+
+
 int
 qemuMonitorJSONHumanCommandWithFd(qemuMonitorPtr mon,
                                   const char *cmd_str,
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index f200729cb1..94b7de76d7 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -1615,6 +1615,58 @@ qemuProcessHandleDumpCompleted(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
 }
 
 
+static int
+qemuProcessHandlePRManagerStatusChanged(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
+                                        virDomainObjPtr vm,
+                                        const char *prManager,
+                                        bool connected,
+                                        void *opaque ATTRIBUTE_UNUSED)
+{
+    qemuDomainObjPrivatePtr priv;
+    size_t i;
+    int ret = -1;
+
+    virObjectLock(vm);
+
+    VIR_DEBUG("pr-manager %s status changed for domain %p %s connected=%d",
+              prManager, vm, vm->def->name, connected);
+
+    if (connected) {
+        /* Connect events are boring. */
+        ret = 0;
+        goto cleanup;
+    }
+    /* Disconnect events are more interesting. */
+
+    for (i = 0; i < vm->def->ndisks; i++) {
+        const char *mgralias;
+
+        mgralias = virStorageSourceChainGetManagedPRAlias(vm->def->disks[i]->src);
+
+        if (STREQ_NULLABLE(prManager, mgralias))
+            break;
+    }
+
+    if (i == vm->def->ndisks) {
+        VIR_DEBUG("pr-manager %s not managed, ignoring event",
+                  prManager);
+        ret = 0;
+        goto cleanup;
+    }
+
+    priv = vm->privateData;
+    priv->prDaemonRunning = false;
+
+    if (qemuProcessStartManagedPRDaemon(vm) < 0)
+        goto cleanup;
+
+    ret = 0;
+ cleanup:
+    virObjectUnlock(vm);
+    return ret;
+}
+
+
 static qemuMonitorCallbacks monitorCallbacks = {
     .eofNotify = qemuProcessHandleMonitorEOF,
     .errorNotify = qemuProcessHandleMonitorError,
@@ -1643,6 +1695,7 @@ static qemuMonitorCallbacks monitorCallbacks = {
     .domainAcpiOstInfo = qemuProcessHandleAcpiOstInfo,
     .domainBlockThreshold = qemuProcessHandleBlockThreshold,
     .domainDumpCompleted = qemuProcessHandleDumpCompleted,
+    .domainPRManagerStatusChanged = qemuProcessHandlePRManagerStatusChanged,
 };
 
 static void
-- 
2.16.4