On 2/28/2024 2:21 AM, Markus Armbruster wrote:
> Steve Sistare <steven.sist...@oracle.com> writes:
>
>> Fail the migration request if options are set that are incompatible
>> with cpr.
>>
>> Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
>> ---
>> migration/migration.c | 17 +++++++++++++++++
>> qapi/migration.json | 2 ++
>> 2 files changed, 19 insertions(+)
>>
>> diff --git a/migration/migration.c b/migration/migration.c
>> index 90a9094..7652fd4 100644
>> --- a/migration/migration.c
>> +++ b/migration/migration.c
>> @@ -1953,6 +1953,23 @@ static bool migrate_prepare(MigrationState *s, bool
>> blk, bool blk_inc,
>> return false;
>> }
>>
>> + if (migrate_mode_is_cpr(s)) {
>> + const char *conflict = NULL;
>> +
>> + if (migrate_postcopy()) {
>> + conflict = "postcopy";
>> + } else if (migrate_background_snapshot()) {
>> + conflict = "background snapshot";
>> + } else if (migrate_colo()) {
>> + conflict = "COLO";
>> + }
>> +
>> + if (conflict) {
>> + error_setg(errp, "Cannot use %s with CPR", conflict);
>> + return false;
>> + }
>> + }
>> +
>> if (blk || blk_inc) {
>> if (migrate_colo()) {
>> error_setg(errp, "No disk migration is required in COLO mode");
>> diff --git a/qapi/migration.json b/qapi/migration.json
>> index 0990297..c6bfe2e 100644
>> --- a/qapi/migration.json
>> +++ b/qapi/migration.json
>> @@ -657,6 +657,8 @@
>> # shared backend must be be non-volatile across reboot, such as by
>> backing
>> # it with a dax device.
>> #
>> +# cpr-reboot may not be used with postcopy, colo, or
>> background-snapshot.
>> +#
>
> @cpr-reboot
>
> COLO
>
> Wrap the line:
>
> # @cpr-reboot may not be used with postcopy, COLO, or
> # background-snapshot.
>
> This doesn't tell the reader what settings exactly do not work with
> @cpr-reboot.
>
> For instance "background-snapshot" is about enabling migration
> capability @background-snapshot. We could write something like "is
> incompatible with enabling migration capability @background-snapshot".
>
> Same for the other two. Worthwhile?
I initially was more precise exactly as you suggest, but I realized that
postcopy encompasses multiple capabilities, and I did not want to enumerate
them, nor require new capabilities related to these 3 to be listed here
if/when they are created, so I generalized. A keyword search in this file
gives unambiguous matches.
Peter pushed the patch a few hours before you sent this.
- Steve
