[libvirt PATCH v2 21/31] qemu_snapshot: refactor validation of snapshot delete

Prepare the validation function for external snapshot delete support. There is one exception when deleting `children-only` snapshots. If the snapshot tree is like this example: snap1 (external) | +- snap2 (internal) | +- snap3 (internal) | +- snap4 (internal) and user calls `snapshot-delete snap1 --children-only` the current snapshot is external but all the children snapshots are internal only and we are able to delete it. Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com&gt; Reviewed-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- src/qemu/qemu_snapshot.c | 73 +++++++++++++++++++++++++--------------- 1 file changed, 46 insertions(+), 27 deletions(-) diff --git a/src/qemu/qemu_snapshot.c b/src/qemu/qemu_snapshot.c index cb4e0dcb78..d7da317e22 100644 --- a/src/qemu/qemu_snapshot.c +++ b/src/qemu/qemu_snapshot.c @@ -100,21 +100,6 @@ qemuSnapObjFromSnapshot(virDomainObj *vm, } -/* Count how many snapshots in a set are external snapshots. */ -static int -qemuSnapshotCountExternal(void *payload, - const char *name G_GNUC_UNUSED, - void *data) -{ - virDomainMomentObj *snap = payload; - int *count = data; - - if (virDomainSnapshotIsExternal(snap)) - (*count)++; - return 0; -} - - int qemuSnapshotFSFreeze(virDomainObj *vm, const char **mountpoints, @@ -2482,26 +2467,60 @@ qemuSnapshotDeleteChildren(virDomainObj *vm, } +typedef struct { + int external; + int internal; +} qemuSnapshotCount; + + +static int +qemuSnapshotCountExternalInternal(void *payload, + const char *name G_GNUC_UNUSED, + void *data) +{ + virDomainMomentObj *snap = payload; + qemuSnapshotCount *count = data; + + if (virDomainSnapshotIsExternal(snap)) { + count->external++; + } else { + count->internal++; + } + + return 0; +} + + static int qemuSnapshotDeleteValidate(virDomainMomentObj *snap, unsigned int flags) { - int external = 0; - - if (!(flags & VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY) && - virDomainSnapshotIsExternal(snap)) - external++; if (flags & (VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN | - VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY)) + VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY)) { + qemuSnapshotCount count = { 0 }; + virDomainMomentForEachDescendant(snap, - qemuSnapshotCountExternal, - &external); + qemuSnapshotCountExternalInternal, + &count); - if (external) { - virReportError(VIR_ERR_CONFIG_UNSUPPORTED, - _("deletion of %d external disk snapshots not " - "supported yet"), external); + if (count.external > 0 && count.internal > 0) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("deletion of external and internal children disk snapshots not supported")); + return -1; + } + + if (count.external > 0) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("deletion of external children disk snapshots not supported")); + return -1; + } + } + + if (virDomainSnapshotIsExternal(snap) && + !(flags & VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("deletion of external disk snapshots not supported")); return -1; } -- 2.39.0