Re: [libvirt PATCH v4 2/4] qemu_monitor: add support for get qemu migration blockers

since qemu 6.0, if migration is blocked for some reason, 'query-migrate' will return an array of error strings describing the migration blockers. This can be used to check whether there are any devices blocking migration, etc. Enable qemu monitor to send this query. This will allow qemuMigrationSrcIsAllowed to dynamically ask for migration blockers, reducing duplication.

Signed-off-by: Eugenio Pérez <eperezma(a)redhat.com&gt; Reviewed-by: Jiri Denemark <jdenemar(a)redhat.com&gt; --- v4: * Separate return type into its own line v3: * Squash some patches * Return ok in qemuMonitorJSONGetMigrationBlockers is there are no blockers. * Move note to function doc. --- src/qemu/qemu_monitor.c | 11 +++++++++ src/qemu/qemu_monitor.h | 4 ++++ src/qemu/qemu_monitor_json.c | 44 ++++++++++++++++++++++++++++++++++++ src/qemu/qemu_monitor_json.h | 3 +++ 4 files changed, 62 insertions(+) diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c index 109107eaae..e0939beecd 100644 --- a/src/qemu/qemu_monitor.c +++ b/src/qemu/qemu_monitor.c @@ -4486,3 +4486,14 @@ qemuMonitorMigrateRecover(qemuMonitor *mon, return qemuMonitorJSONMigrateRecover(mon, uri); } + +int +qemuMonitorGetMigrationBlockers(qemuMonitor *mon, + char ***blockers)

+{ + VIR_DEBUG("blockers=%p", blockers); + + QEMU_CHECK_MONITOR(mon); + + return qemuMonitorJSONGetMigrationBlockers(mon, blockers); +} diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h index cc1a0bc8c9..b82f198285 100644 --- a/src/qemu/qemu_monitor.h +++ b/src/qemu/qemu_monitor.h @@ -1543,3 +1543,7 @@ qemuMonitorChangeMemoryRequestedSize(qemuMonitor *mon, int qemuMonitorMigrateRecover(qemuMonitor *mon, const char *uri); + +int +qemuMonitorGetMigrationBlockers(qemuMonitor *mon, + char ***blockers); diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c index 5e4a86e5ad..6b26dfcb54 100644 --- a/src/qemu/qemu_monitor_json.c +++ b/src/qemu/qemu_monitor_json.c @@ -3338,6 +3338,50 @@ int qemuMonitorJSONMigrate(qemuMonitor *mon, return 0; } +/* + * Get the exposed migration blockers. + * + * This function assume qemu has the capability of request them. + * + * It returns a NULL terminated array on blockers if there are any, or it set + * it to NULL otherwise. + */ +int +qemuMonitorJSONGetMigrationBlockers(qemuMonitor *mon, + char ***blockers) +{ + g_autoptr(virJSONValue) cmd = NULL; + g_autoptr(virJSONValue) reply = NULL; + virJSONValue *data; + virJSONValue *jblockers; + size_t i; + + *blockers = NULL; + if (!(cmd = qemuMonitorJSONMakeCommand("query-migrate", NULL))) + return -1; + + if (qemuMonitorJSONCommand(mon, cmd, &reply) < 0) + return -1; + + if (qemuMonitorJSONCheckReply(cmd, reply, VIR_JSON_TYPE_OBJECT) < 0) + return -1; + + data = virJSONValueObjectGetObject(reply, "return"); + + if (!(jblockers = virJSONValueObjectGetArray(data, "blocked-reasons"))) + return 0; + + *blockers = g_new0(char *, virJSONValueArraySize(jblockers) + 1); + for (i = 0; i < virJSONValueArraySize(jblockers); i++) { + virJSONValue *jblocker = virJSONValueArrayGet(jblockers, i); + const char *blocker = virJSONValueGetString(jblocker); + + (*blockers)[i] = g_strdup(blocker); + } + + return 0; +} + int qemuMonitorJSONMigrateCancel(qemuMonitor *mon) { g_autoptr(virJSONValue) cmd = qemuMonitorJSONMakeCommand("migrate_cancel", NULL); diff --git a/src/qemu/qemu_monitor_json.h b/src/qemu/qemu_monitor_json.h index 2759566892..e4c65e250e 100644 --- a/src/qemu/qemu_monitor_json.h +++ b/src/qemu/qemu_monitor_json.h @@ -184,6 +184,9 @@ qemuMonitorJSONMigrate(qemuMonitor *mon, unsigned int flags, const char *uri); int +qemuMonitorJSONGetMigrationBlockers(qemuMonitor *mon, + char ***blockers); +int qemuMonitorJSONGetSpiceMigrationStatus(qemuMonitor *mon, bool *spice_migrated);