Re: [libvirt] [PATCH v9 12/13] backup: Wire up qemu checkpoint commands over QMP

Time to actually issue the QMP transactions that create and delete persistent checkpoints. For create, we only need one transaction: inside, we visit all disks affected by the checkpoint, and create a new enabled bitmap, as well as disabling the bitmap of the parent checkpoint (if any). For deletion, we need multiple calls: if the checkpoint to be deleted is active, we must enable the parent; then we must merge the existing checkpoint into the parent, and finally we can delete the checkpoint. Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; --- src/qemu/qemu_domain.c | 105 ++++++++++++++++++++++++++++++----------- src/qemu/qemu_driver.c | 92 ++++++++++++++++++++++++++++++++++-- 2 files changed, 165 insertions(+), 32 deletions(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 03a143a228..2fca7bd0b8 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -8960,45 +8960,93 @@ qemuDomainCheckpointDiscard(virQEMUDriverPtr driver, char *chkFile = NULL; int ret = -1; virDomainMomentObjPtr parentchk = NULL; + virDomainCheckpointDefPtr parentdef = NULL; virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + size_t i, j; + virJSONValuePtr arr = NULL; - if (!metadata_only) { - if (!virDomainObjIsActive(vm)) { - virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s", - _("cannot remove checkpoint from inactive domain")); - goto cleanup; - } else { - /* TODO: Implement QMP sequence to merge bitmaps */ - // qemuDomainObjPrivatePtr priv; - // priv = vm->privateData; - // qemuDomainObjEnterMonitor(driver, vm); - // /* we continue on even in the face of error */ - // qemuMonitorDeleteCheckpoint(priv->mon, chk->def->name); - // ignore_value(qemuDomainObjExitMonitor(driver, vm)); - } + if (!metadata_only && !virDomainObjIsActive(vm)) { + virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s", + _("cannot remove checkpoint from inactive domain")); + goto cleanup; } if (virAsprintf(&chkFile, "%s/%s/%s.xml", cfg->checkpointDir, vm->def->name, chk->def->name) < 0) goto cleanup; + if (chk->def->parent_name) { + parentchk = virDomainCheckpointFindByName(vm->checkpoints, + chk->def->parent_name); + if (!parentchk) { + VIR_WARN("missing parent checkpoint matching name '%s'", + chk->def->parent_name); + } + parentdef = virDomainCheckpointObjGetDef(parentchk); + } + + if (!metadata_only) { + qemuDomainObjPrivatePtr priv = vm->privateData; + bool success = true; + virDomainCheckpointDefPtr chkdef = virDomainCheckpointObjGetDef(chk); + + if (qemuBlockNodeNamesDetect(driver, vm, QEMU_ASYNC_JOB_NONE) < 0) + goto cleanup;

+ qemuDomainObjEnterMonitor(driver, vm); + for (i = 0; i < chkdef->ndisks; i++) { + virDomainCheckpointDiskDef *disk = &chkdef->disks[i]; + const char *node; + + if (disk->type != VIR_DOMAIN_CHECKPOINT_TYPE_BITMAP) + continue; + + node = qemuBlockNodeLookup(vm, disk->name); + if (parentchk) { + arr = virJSONValueNewArray(); + if (!arr || + virJSONValueArrayAppendString(arr, disk->bitmap) < 0) { + success = false; + break; + } + + for (j = 0; j < parentdef->ndisks; j++) { + virDomainCheckpointDiskDef *disk2; + + disk2 = &parentdef->disks[j]; + if (STRNEQ(disk->name, disk2->name)) + continue; + if (chk == virDomainCheckpointGetCurrent(vm->checkpoints) &&

+ qemuMonitorEnableBitmap(priv->mon, node, + disk2->bitmap) < 0) { + success = false; + break; + } + if (qemuMonitorMergeBitmaps(priv->mon, node, + disk2->bitmap, &arr) < 0) { + success = false; + break; + } + } + } + if (qemuMonitorDeleteBitmap(priv->mon, node, disk->bitmap) < 0) { + success = false; + break; + } + } + if (qemuDomainObjExitMonitor(driver, vm) < 0 || !success) + goto cleanup; + } + if (chk == virDomainCheckpointGetCurrent(vm->checkpoints)) { virDomainCheckpointSetCurrent(vm->checkpoints, NULL); - if (update_parent && chk->def->parent_name) { - parentchk = virDomainCheckpointFindByName(vm->checkpoints, - chk->def->parent_name); - if (!parentchk) { - VIR_WARN("missing parent checkpoint matching name '%s'", + if (update_parent && parentchk) { + virDomainCheckpointSetCurrent(vm->checkpoints, parentchk); + if (qemuDomainCheckpointWriteMetadata(vm, parentchk, driver->caps, + driver->xmlopt, + cfg->checkpointDir) < 0) { + VIR_WARN("failed to set parent checkpoint '%s' as current", chk->def->parent_name); - } else { - virDomainCheckpointSetCurrent(vm->checkpoints, parentchk); - if (qemuDomainCheckpointWriteMetadata(vm, parentchk, driver->caps, - driver->xmlopt, - cfg->checkpointDir) < 0) { - VIR_WARN("failed to set parent checkpoint '%s' as current", - chk->def->parent_name); - virDomainCheckpointSetCurrent(vm->checkpoints, NULL); - } + virDomainCheckpointSetCurrent(vm->checkpoints, NULL); } } } @@ -9014,6 +9062,7 @@ qemuDomainCheckpointDiscard(virQEMUDriverPtr driver, cleanup: VIR_FREE(chkFile); virObjectUnref(cfg); + virJSONValueFree(arr); return ret; } diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 702a715902..b37307abc7 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -47,6 +47,7 @@ #include "qemu_hostdev.h" #include "qemu_hotplug.h" #include "qemu_monitor.h" +#include "qemu_monitor_json.h"

#include "qemu_process.h" #include "qemu_migration.h" #include "qemu_migration_params.h" @@ -16994,6 +16995,53 @@ qemuDomainCheckpointPrepare(virQEMUDriverPtr driver, virCapsPtr caps, return ret; } +static int +qemuDomainCheckpointAddActions(virDomainObjPtr vm, + virJSONValuePtr actions, + virDomainMomentObjPtr old_current, + virDomainCheckpointDefPtr def) +{ + size_t i, j; + int ret = -1; + virDomainCheckpointDefPtr olddef; + + olddef = virDomainCheckpointObjGetDef(old_current); + for (i = 0; i < def->ndisks; i++) { + virDomainCheckpointDiskDef *disk = &def->disks[i]; + const char *node; + + if (disk->type != VIR_DOMAIN_CHECKPOINT_TYPE_BITMAP) + continue; + node = qemuBlockNodeLookup(vm, disk->name); + if (qemuMonitorJSONTransactionAdd(actions, + "block-dirty-bitmap-add", + "s:node", node, + "s:name", disk->bitmap, + "b:persistent", true, + NULL) < 0) + goto cleanup; + if (old_current) { + for (j = 0; j < olddef->ndisks; j++) { + virDomainCheckpointDiskDef *disk2; + + disk2 = &olddef->disks[j]; + if (STRNEQ(disk->name, disk2->name)) + continue; + if (disk2->type == VIR_DOMAIN_CHECKPOINT_TYPE_BITMAP && + qemuMonitorJSONTransactionAdd(actions, + "block-dirty-bitmap-disable",

+ "s:node", node, + "s:name", disk2->bitmap, + NULL) < 0) + goto cleanup; + } + } + } + ret = 0; + + cleanup: + return ret; +} static virDomainCheckpointPtr qemuDomainCheckpointCreateXML(virDomainPtr domain,

@@ -17077,10 +17135,10 @@ qemuDomainCheckpointCreateXML(virDomainPtr domain, def = NULL; } - current = virDomainCheckpointGetCurrent(vm->checkpoints); - if (current) { + other = virDomainCheckpointGetCurrent(vm->checkpoints); + if (other) { if (!redefine && - VIR_STRDUP(chk->def->parent_name, current->def->name) < 0) + VIR_STRDUP(chk->def->parent_name, other->def->name) < 0) goto endjob; if (update_current) { virDomainCheckpointSetCurrent(vm->checkpoints, NULL);

@@ -17328,6 +17396,22 @@ qemuDomainCheckpointDelete(virDomainCheckpointPtr checkpoint, if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) goto cleanup; + priv = vm->privateData; + if (!metadata_only) { + /* Until qemu-img supports offline bitmap deletion, we are stuck + * with requiring a running guest */ + if (!virDomainObjIsActive(vm)) { + virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s", + _("cannot delete checkpoint for inactive domain")); + goto endjob; + } + if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BITMAP_MERGE)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("qemu binary lacks persistent bitmaps support")); + goto endjob; + } + } + if (!(chk = qemuCheckObjFromCheckpoint(vm, checkpoint))) goto endjob;