Re: [PATCH 04/19] qemu: checkpoint: Introduce support for deleting checkpoints accross snapshots

Allow deleting of checkpoints when snapshots were created along. The code tracks and modifies the checkpoint list so that backups can still be taken with such a backing chain. This unfortunately requires to rename few bitmaps (by copying and deleting them) in some cases. Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- src/qemu/qemu_checkpoint.c | 112 ++++++++++++++++++++++++++++--------- src/qemu/qemu_checkpoint.h | 5 +- tests/qemublocktest.c | 34 +++++++---- 3 files changed, 111 insertions(+), 40 deletions(-) diff --git a/src/qemu/qemu_checkpoint.c b/src/qemu/qemu_checkpoint.c index e75cdd0458..087a740cf8 100644 --- a/src/qemu/qemu_checkpoint.c +++ b/src/qemu/qemu_checkpoint.c @@ -24,6 +24,7 @@ #include "qemu_capabilities.h" #include "qemu_monitor.h" #include "qemu_domain.h" +#include "qemu_block.h" #include "virerror.h" #include "virlog.h" @@ -150,39 +151,92 @@ qemuCheckpointFindActiveDiskInParent(virDomainObjPtr vm, int qemuCheckpointDiscardDiskBitmaps(virStorageSourcePtr src, + virHashTablePtr blockNamedNodeData, const char *delbitmap, const char *parentbitmap, - bool chkcurrent, - virJSONValuePtr actions) + virJSONValuePtr actions, + const char *diskdst) { - if (parentbitmap) { - g_autoptr(virJSONValue) arr = NULL; + virStorageSourcePtr n = src; - if (!(arr = virJSONValueNewArray())) - return -1; + /* find the backing chain entry with bitmap named '@bitmap' */

+ while (n) { + qemuBlockNamedNodeDataBitmapPtr tmp; - if (qemuMonitorTransactionBitmapMergeSourceAddBitmap(arr, - src->nodeformat, - delbitmap) < 0) - return -1; + if ((tmp = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData, + n, delbitmap))) { + break; + } + + n = n->backingStore; + } + + if (!n) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("bitmap '%s' not found in backing chain of '%s'"), + delbitmap, diskdst); + return -1; + } - if (chkcurrent) { - if (qemuMonitorTransactionBitmapEnable(actions, - src->nodeformat, - parentbitmap) < 0) + while (n) { + qemuBlockNamedNodeDataBitmapPtr srcbitmap; + + if (!(srcbitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData, + n, delbitmap))) + break; + + /* For the actual checkpoint deletion we will merge any bitmap into the + * bitmap of the parent checkpoint (@mergebitmap) or for any image

+ * where the parent checkpoint bitmap is not present we must rename + * the bitmap of the deleted checkpoint into the bitmap of the parent + * checkpoint as qemu can't currently take the allocation map and turn + * it into a bitmap and thus we wouldn't be able to do a backup. */ + if (parentbitmap) { + qemuBlockNamedNodeDataBitmapPtr dstbitmap; + g_autoptr(virJSONValue) arr = NULL; + + dstbitmap = qemuBlockNamedNodeDataGetBitmapByName(blockNamedNodeData, + n, parentbitmap); +