Re: [libvirt PATCH 4/6] qemu: Add support for optional migration capabilities

We enable various migration capabilities according to the flags passed to a migration API. Missing support for such capabilities results in an error because they are required by the corresponding flag. This patch adds support for additional optional capability we may want to enable for a given API flag in case it is supported. This is useful for capabilities which are not critical for the flags to be supported, but they can make things work better in some way. Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com&gt; --- src/qemu/qemu_migration.c | 8 ++--- src/qemu/qemu_migration_params.c | 57 +++++++++++++++++++++++++++++--- src/qemu/qemu_migration_params.h | 1 + 3 files changed, 57 insertions(+), 9 deletions(-)

@@ -1303,16 +1324,42 @@ qemuMigrationParamsCheck(virDomainObj *vm, party = QEMU_MIGRATION_DESTINATION; for (cap = 0; cap < QEMU_MIGRATION_CAP_LAST; cap++) { - bool state = false; - - ignore_value(virBitmapGetBit(migParams->caps, cap, &state)); - - if (state && !qemuMigrationCapsGet(vm, cap)) { + bool enable = false; + bool optional = false; + bool remoteOpt = false; + bool remote = false; + bool qemu = qemuMigrationCapsGet(vm, cap); + + ignore_value(virBitmapGetBit(migParams->caps, cap, &enable)); + ignore_value(virBitmapGetBit(migParams->optional, cap, &optional)); + ignore_value(virBitmapGetBit(migParams->remoteOptional, cap, &remoteOpt)); + ignore_value(virBitmapGetBit(remoteSupported, cap, &remote)); + + if (enable && !qemu) { virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, _("Migration option '%1$s' is not supported by QEMU binary"), qemuMigrationCapabilityTypeToString(cap)); return -1; } + + if (optional) { + if (!qemu) { + VIR_DEBUG("Optional migration capability '%s' not supported by QEMU", + qemuMigrationCapabilityTypeToString(cap)); + optional = false; + } else if (remoteOpt && ! remote) {

+ VIR_DEBUG("Optional migration capability '%s' not supported " + "by the other side of migration", + qemuMigrationCapabilityTypeToString(cap));