Re: [PATCH 18/19] qemu: migration: Migrate block dirty bitmaps corresponding to checkpoints

Preserve block dirty bitmaps after migration with QEMU_MONITOR_MIGRATE_NON_SHARED_(DISK|INC). This patch implements functions which offer the bitmaps to the destination, check for eligibility on destination and then configure source for the migration. Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- src/qemu/qemu_migration.c | 333 +++++++++++++++++++++++++++++++++++++- 1 file changed, 331 insertions(+), 2 deletions(-) diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c index 36424f8493..16bfad0390 100644 --- a/src/qemu/qemu_migration.c +++ b/src/qemu/qemu_migration.c

@@ -2528,6 +2619,92 @@ qemuMigrationDstPrepare(virDomainObjPtr vm, migrateFrom, fd, NULL); } + +/** + * qemuMigrationDstPrepareAnyBlockDirtyBitmaps: + * @vm: domain object + * @mig: migration cookie + * @migParams: migration parameters + * @flags: migration flags + * + * Checks whether block dirty bitmaps offered by the migration source are + * to be migrated (e.g. they don't exist, the destination is compatible etc) + * and sets up destination qemu for migrating the bitmaps as well as updates the + * list of eligible bitmaps in the migration cookie to be sent back to the + * source. + */ +static int +qemuMigrationDstPrepareAnyBlockDirtyBitmaps(virDomainObjPtr vm, + qemuMigrationCookiePtr mig, + qemuMigrationParamsPtr migParams, + unsigned int flags) +{ + qemuDomainObjPrivatePtr priv = vm->privateData; + g_autoptr(virJSONValue) mapping = NULL; + g_autoptr(GHashTable) blockNamedNodeData = NULL; + GSList *nextdisk; + + if (!mig->nbd || + !mig->blockDirtyBitmaps || + !(flags & (VIR_MIGRATE_NON_SHARED_DISK | VIR_MIGRATE_NON_SHARED_INC)) || + !virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_PARAM_BLOCK_BITMAP_MAPPING)) + return 0;

+ + if (qemuMigrationCookieBlockDirtyBitmapsMatchDisks(vm->def, mig->blockDirtyBitmaps) < 0) + return -1; + + if (!(blockNamedNodeData = qemuBlockGetNamedNodeData(vm, QEMU_ASYNC_JOB_MIGRATION_IN))) + return -1; + + for (nextdisk = mig->blockDirtyBitmaps; nextdisk; nextdisk = nextdisk->next) { + qemuMigrationBlockDirtyBitmapsDiskPtr disk = nextdisk->data; + qemuBlockNamedNodeDataPtr nodedata; + GSList *nextbitmap; + + if (!(nodedata = virHashLookup(blockNamedNodeData, disk->nodename))) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("failed to find data for block node '%s'"), + disk->nodename); + return -1; + } + + /* don't migrate bitmaps into non-qcow2v3+ images */

+ if (disk->disk->src->format != VIR_STORAGE_FILE_QCOW2 || + nodedata->qcow2v2) { + disk->skip = true;

+ continue; + } + + for (nextbitmap = disk->bitmaps; nextbitmap; nextbitmap = nextbitmap->next) { + qemuMigrationBlockDirtyBitmapsDiskBitmapPtr bitmap = nextbitmap->data; + size_t k; + + /* don't migrate into existing bitmaps */ + for (k = 0; k < nodedata->nbitmaps; k++) { + if (STREQ(bitmap->bitmapname, nodedata->bitmaps[k]->name)) { + bitmap->skip = true;

+ break; + } + } + + if (bitmap->skip) + continue; + } + } + + if (qemuMigrationCookieBlockDirtyBitmapsToParams(mig->blockDirtyBitmaps, + &mapping) < 0) + return -1; + + if (!mapping) + return 0; + + qemuMigrationParamsSetBlockDirtyBitmapMapping(migParams, &mapping); + mig->flags |= QEMU_MIGRATION_COOKIE_BLOCK_DIRTY_BITMAPS; + return 0; +} + + static int qemuMigrationDstPrepareAny(virQEMUDriverPtr driver, virConnectPtr dconn,

+static int +qemuMigrationSrcRunPrepareBlockDirtyBitmaps(virDomainObjPtr vm, + qemuMigrationCookiePtr mig, + qemuMigrationParamsPtr migParams, + unsigned int flags) + +{ + g_autoptr(virJSONValue) mapping = NULL; + + if (!mig->blockDirtyBitmaps) + return 0; + + if (qemuMigrationCookieBlockDirtyBitmapsMatchDisks(vm->def, mig->blockDirtyBitmaps) < 0) + return -1; + + /* For QEMU_MONITOR_MIGRATE_NON_SHARED_INC we can migrate the bitmaps + * directly, otherwise we must create merged bitmaps from the whole + * chain */ + + if (!(flags & QEMU_MONITOR_MIGRATE_NON_SHARED_INC) && + qemuMigrationSrcRunPrepareBlockDirtyBitmapsMerge(vm, mig))

+ return -1; + + if (qemuMigrationCookieBlockDirtyBitmapsToParams(mig->blockDirtyBitmaps, + &mapping) < 0) + return -1; + + qemuMigrationParamsSetBlockDirtyBitmapMapping(migParams, &mapping); + return 0; +} + + static int qemuMigrationSrcRun(virQEMUDriverPtr driver, virDomainObjPtr vm,