[PATCH 23/32] qemu: backup: Rewrite backup bitmap handling to the new bitmap semantics

Reuse qemuBlockGetBitmapMergeActions which allows to remove the ad-hoc iplementatio of bitmap merging for backup. The new approach is simpler and also more robust in case some of the bitmaps break as they remove the dependancy on the whole chain of bitmaps working. The new approach also allows backups if a snapshot is created outside of libvirt. Additionally the code is greatly simplified. Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- src/qemu/qemu_backup.c | 220 +++--------------- src/qemu/qemu_backup.h | 12 +- tests/qemublocktest.c | 86 ++----- .../backupmerge/empty-out.json | 4 +- 4 files changed, 63 insertions(+), 259 deletions(-) diff --git a/src/qemu/qemu_backup.c b/src/qemu/qemu_backup.c index 495da86ff0..7c337846dc 100644 --- a/src/qemu/qemu_backup.c +++ b/src/qemu/qemu_backup.c @@ -173,199 +173,58 @@ qemuBackupDiskDataCleanup(virDomainObjPtr vm, } -/** - * qemuBackupBeginCollectIncrementalCheckpoints: - * @vm: domain object - * @incrFrom: name of checkpoint representing starting point of incremental backup - * - * Returns a NULL terminated list of pointers to checkpoint definitions in - * chronological order starting from the 'current' checkpoint until reaching - * @incrFrom. - */ -static virDomainMomentDefPtr * -qemuBackupBeginCollectIncrementalCheckpoints(virDomainObjPtr vm, - const char *incrFrom) -{ - virDomainMomentObjPtr n = virDomainCheckpointGetCurrent(vm->checkpoints); - g_autofree virDomainMomentDefPtr *incr = NULL; - size_t nincr = 0; - - while (n) { - virDomainMomentDefPtr def = n->def; - - if (VIR_APPEND_ELEMENT_COPY(incr, nincr, def) < 0) - return NULL; - - if (STREQ(def->name, incrFrom)) { - def = NULL; - if (VIR_APPEND_ELEMENT_COPY(incr, nincr, def) < 0) - return NULL; - - return g_steal_pointer(&incr); - } - - if (!n->def->parent_name) - break; - - n = virDomainCheckpointFindByName(vm->checkpoints, n->def->parent_name); - } - - virReportError(VIR_ERR_OPERATION_INVALID, - _("could not locate checkpoint '%s' for incremental backup"), - incrFrom); - return NULL; -} - - -static int -qemuBackupGetBitmapMergeRange(virStorageSourcePtr from, - const char *bitmapname, - virJSONValuePtr *actions, - virStorageSourcePtr *to, - const char *diskdst, - virHashTablePtr blockNamedNodeData) +int +qemuBackupDiskPrepareOneBitmapsChain(virStorageSourcePtr backingChain, + virStorageSourcePtr targetsrc, + const char *targetbitmap, + const char *incremental, + virJSONValuePtr actions, + virHashTablePtr blockNamedNodeData) { - g_autoptr(virJSONValue) ret = virJSONValueNewArray(); - virStorageSourcePtr tmpsrc = NULL; - virStorageSourcePtr n; - bool foundbitmap = false; + g_autoptr(virJSONValue) tmpactions = NULL; - for (n = from; virStorageSourceIsBacking(n); n = n->backingStore) { - qemuBlockNamedNodeDataBitmapPtr bitmap = NULL; - - if (!(bitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData, - n, - bitmapname))) - break; - - foundbitmap = true; - - if (bitmap->inconsistent) { - virReportError(VIR_ERR_INVALID_ARG, - _("bitmap '%s' for image '%s%u' is inconsistent"), - bitmap->name, diskdst, n->id); - return -1; - } - - if (qemuMonitorTransactionBitmapMergeSourceAddBitmap(ret, - n->nodeformat, - bitmapname) < 0) - return -1; - - tmpsrc = n; - } - - if (!foundbitmap) { - virReportError(VIR_ERR_INVALID_ARG, - _("failed to find bitmap '%s' in image '%s%u'"), - bitmapname, diskdst, from->id); + if (qemuBlockGetBitmapMergeActions(backingChain, NULL, targetsrc, + incremental, targetbitmap, NULL, + &tmpactions, + blockNamedNodeData) < 0) return -1; - } - *actions = g_steal_pointer(&ret); - *to = tmpsrc; + if (tmpactions && + virJSONValueArrayConcat(actions, tmpactions) < 0) + return -1; return 0; } -virJSONValuePtr -qemuBackupDiskPrepareOneBitmapsChain(virDomainMomentDefPtr *incremental, - virStorageSourcePtr backingChain, - virHashTablePtr blockNamedNodeData, - const char *diskdst) -{ - g_autoptr(virJSONValue) ret = NULL; - size_t incridx = 0; - virStorageSourcePtr n = backingChain; - - ret = virJSONValueNewArray(); - - for (incridx = 0; incremental[incridx]; incridx++) { - g_autoptr(virJSONValue) tmp = virJSONValueNewArray(); - virStorageSourcePtr tmpsrc = NULL; - virDomainCheckpointDefPtr chkdef = (virDomainCheckpointDefPtr) incremental[incridx]; - bool checkpoint_has_disk = false; - size_t i; - - for (i = 0; i < chkdef->ndisks; i++) { - if (STRNEQ_NULLABLE(diskdst, chkdef->disks[i].name)) - continue; - - if (chkdef->disks[i].type == VIR_DOMAIN_CHECKPOINT_TYPE_BITMAP) - checkpoint_has_disk = true; - - break; - } - - if (!checkpoint_has_disk) { - if (!incremental[incridx + 1]) { - virReportError(VIR_ERR_INVALID_ARG, - _("disk '%s' not found in checkpoint '%s'"), - diskdst, incremental[incridx]->name); - return NULL; - } - - continue; - } - - if (qemuBackupGetBitmapMergeRange(n, incremental[incridx]->name, - &tmp, &tmpsrc, diskdst, - blockNamedNodeData) < 0) - return NULL; - - if (virJSONValueArrayConcat(ret, tmp) < 0) - return NULL; - - n = tmpsrc; - } - - return g_steal_pointer(&ret); -} - - static int qemuBackupDiskPrepareOneBitmaps(struct qemuBackupDiskData *dd, virJSONValuePtr actions, - virDomainMomentDefPtr *incremental, virHashTablePtr blockNamedNodeData) { - g_autoptr(virJSONValue) mergebitmaps = NULL; - g_autoptr(virJSONValue) mergebitmapsstore = NULL; - - if (!(mergebitmaps = qemuBackupDiskPrepareOneBitmapsChain(incremental, - dd->domdisk->src, - blockNamedNodeData, - dd->domdisk->dst))) - return -1; - - if (!(mergebitmapsstore = virJSONValueCopy(mergebitmaps))) - return -1; - - if (qemuMonitorTransactionBitmapAdd(actions, - dd->domdisk->src->nodeformat, - dd->incrementalBitmap, - false, - true, 0) < 0) - return -1; - - if (qemuMonitorTransactionBitmapMerge(actions, - dd->domdisk->src->nodeformat, - dd->incrementalBitmap, - &mergebitmaps) < 0) + if (!qemuBlockBitmapChainIsValid(dd->domdisk->src, + dd->backupdisk->incremental, + blockNamedNodeData)) { + virReportError(VIR_ERR_INVALID_ARG, + _("missing or broken bitmap '%s' for disk '%s'"), + dd->backupdisk->incremental, dd->domdisk->dst); return -1; + } - if (qemuMonitorTransactionBitmapAdd(actions, - dd->store->nodeformat, - dd->incrementalBitmap, - false, - true, 0) < 0) + if (qemuBackupDiskPrepareOneBitmapsChain(dd->domdisk->src, + dd->domdisk->src, + dd->incrementalBitmap, + dd->backupdisk->incremental, + actions, + blockNamedNodeData) < 0) return -1; - if (qemuMonitorTransactionBitmapMerge(actions, - dd->store->nodeformat, - dd->incrementalBitmap, - &mergebitmapsstore) < 0) + if (qemuBackupDiskPrepareOneBitmapsChain(dd->domdisk->src, + dd->store, + dd->incrementalBitmap, + dd->backupdisk->incremental, + actions, + blockNamedNodeData) < 0) return -1; return 0; @@ -382,7 +241,6 @@ qemuBackupDiskPrepareDataOne(virDomainObjPtr vm, virQEMUDriverConfigPtr cfg) { qemuDomainObjPrivatePtr priv = vm->privateData; - g_autofree virDomainMomentDefPtr *incremental = NULL; /* set data structure */ dd->backupdisk = backupdisk; @@ -420,16 +278,12 @@ qemuBackupDiskPrepareDataOne(virDomainObjPtr vm, return -1; if (dd->backupdisk->incremental) { - if (!(incremental = qemuBackupBeginCollectIncrementalCheckpoints(vm, dd->backupdisk->incremental))) - return -1; - if (dd->backupdisk->exportbitmap) dd->incrementalBitmap = g_strdup(dd->backupdisk->exportbitmap); else dd->incrementalBitmap = g_strdup_printf("backup-%s", dd->domdisk->dst); - if (qemuBackupDiskPrepareOneBitmaps(dd, actions, incremental, - blockNamedNodeData) < 0) + if (qemuBackupDiskPrepareOneBitmaps(dd, actions, blockNamedNodeData) < 0) return -1; } @@ -883,8 +737,8 @@ qemuBackupBegin(virDomainObjPtr vm, if (!(blockNamedNodeData = qemuBlockGetNamedNodeData(vm, QEMU_ASYNC_JOB_BACKUP))) goto endjob; - if ((ndd = qemuBackupDiskPrepareData(vm, def, blockNamedNodeData, - actions, cfg, &dd)) <= 0) { + if ((ndd = qemuBackupDiskPrepareData(vm, def, blockNamedNodeData, actions, + cfg, &dd)) <= 0) { if (ndd == 0) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", _("no disks selected for backup")); diff --git a/src/qemu/qemu_backup.h b/src/qemu/qemu_backup.h index b19c3bf1c9..075fde709b 100644 --- a/src/qemu/qemu_backup.h +++ b/src/qemu/qemu_backup.h @@ -53,8 +53,10 @@ qemuBackupGetJobInfoStats(virQEMUDriverPtr driver, qemuDomainJobInfoPtr jobInfo); /* exported for testing */ -virJSONValuePtr -qemuBackupDiskPrepareOneBitmapsChain(virDomainMomentDefPtr *incremental, - virStorageSourcePtr backingChain, - virHashTablePtr blockNamedNodeData, - const char *diskdst); +int +qemuBackupDiskPrepareOneBitmapsChain(virStorageSourcePtr backingChain, + virStorageSourcePtr targetsrc, + const char *targetbitmap, + const char *incremental, + virJSONValuePtr actions, + virHashTablePtr blockNamedNodeData); diff --git a/tests/qemublocktest.c b/tests/qemublocktest.c index 9e142a8851..30662f6f79 100644 --- a/tests/qemublocktest.c +++ b/tests/qemublocktest.c @@ -716,65 +716,6 @@ testQemuBitmapGetFakeChainEntry(virStorageSourcePtr src, } -typedef virDomainMomentDefPtr testMomentList; - -static void -testMomentListFree(testMomentList *list) -{ - testMomentList *tmp = list; - - if (!list) - return; - - while (*tmp) { - virObjectUnref(*tmp); - tmp++; - } - - g_free(list); -} - -G_DEFINE_AUTOPTR_CLEANUP_FUNC(testMomentList, testMomentListFree); - -static virDomainMomentDefPtr -testQemuBackupGetIncrementalMoment(const char *name) -{ - virDomainCheckpointDefPtr checkpoint = NULL; - - if (!(checkpoint = virDomainCheckpointDefNew())) - abort(); - - checkpoint->disks = g_new0(virDomainCheckpointDiskDef, 1); - checkpoint->ndisks = 1; - - checkpoint->disks[0].name = g_strdup("testdisk"); - checkpoint->disks[0].type = VIR_DOMAIN_CHECKPOINT_TYPE_BITMAP; - - checkpoint->parent.name = g_strdup(name); - - return (virDomainMomentDefPtr) checkpoint; -} - - -static virDomainMomentDefPtr * -testQemuBackupGetIncremental(const char *incFrom) -{ - const char *checkpoints[] = {"current", "d", "c", "b", "a"}; - virDomainMomentDefPtr *incr; - size_t i; - - incr = g_new0(virDomainMomentDefPtr, G_N_ELEMENTS(checkpoints) + 1); - - for (i = 0; i < G_N_ELEMENTS(checkpoints); i++) { - incr[i] = testQemuBackupGetIncrementalMoment(checkpoints[i]); - - if (STREQ(incFrom, checkpoints[i])) - break; - } - - return incr; -} - static const char *backupDataPrefix = "qemublocktestdata/backupmerge/"; struct testQemuBackupIncrementalBitmapCalculateData { @@ -791,10 +732,10 @@ testQemuBackupIncrementalBitmapCalculate(const void *opaque) const struct testQemuBackupIncrementalBitmapCalculateData *data = opaque; g_autoptr(virJSONValue) nodedatajson = NULL; g_autoptr(virHashTable) nodedata = NULL; - g_autoptr(virJSONValue) mergebitmaps = NULL; - g_autofree char *actual = NULL; + g_autoptr(virJSONValue) actions = virJSONValueNewArray(); g_autofree char *expectpath = NULL; - g_autoptr(testMomentList) incremental = NULL; + g_autoptr(virStorageSource) target = NULL; + g_auto(virBuffer) buf = VIR_BUFFER_INITIALIZER; expectpath = g_strdup_printf("%s/%s%s-out.json", abs_srcdir, backupDataPrefix, data->name); @@ -808,19 +749,24 @@ testQemuBackupIncrementalBitmapCalculate(const void *opaque) return -1; } - incremental = testQemuBackupGetIncremental(data->incremental); + if (!(target = virStorageSourceNew())) + return -1; - if ((mergebitmaps = qemuBackupDiskPrepareOneBitmapsChain(incremental, - data->chain, - nodedata, - "testdisk"))) { - if (!(actual = virJSONValueToString(mergebitmaps, true))) + target->nodeformat = g_strdup_printf("target_node"); + + if (qemuBackupDiskPrepareOneBitmapsChain(data->chain, + target, + "target-bitmap-name", + data->incremental, + actions, + nodedata) >= 0) { + if (virJSONValueToBuffer(actions, &buf, true) < 0) return -1; } else { - actual = g_strdup("NULL\n"); + virBufferAddLit(&buf, "NULL\n"); } - return virTestCompareToFile(actual, expectpath); + return virTestCompareToFile(virBufferCurrentContent(&buf), expectpath); } diff --git a/tests/qemublocktestdata/backupmerge/empty-out.json b/tests/qemublocktestdata/backupmerge/empty-out.json index 7951defec1..41b42e677b 100644 --- a/tests/qemublocktestdata/backupmerge/empty-out.json +++ b/tests/qemublocktestdata/backupmerge/empty-out.json @@ -1 +1,3 @@ -NULL +[ + +] -- 2.26.2