From: Fabiano Rosas <faro...@suse.de> The mapped-ram migration format needs a channel that supports seeking to be able to write each page to an arbitrary offset in the migration stream.
Reviewed-by: "Daniel P. Berrangé" <berra...@redhat.com> Reviewed-by: Peter Xu <pet...@redhat.com> Signed-off-by: Fabiano Rosas <faro...@suse.de> Link: https://lore.kernel.org/r/20240229153017.2221-9-faro...@suse.de Signed-off-by: Peter Xu <pet...@redhat.com> --- migration/migration.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/migration/migration.c b/migration/migration.c index 69f68f940d..2669600d25 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -148,10 +148,39 @@ static bool transport_supports_multi_channels(MigrationAddress *addr) return false; } +static bool migration_needs_seekable_channel(void) +{ + return migrate_mapped_ram(); +} + +static bool transport_supports_seeking(MigrationAddress *addr) +{ + if (addr->transport == MIGRATION_ADDRESS_TYPE_FILE) { + return true; + } + + /* + * At this point, the user might not yet have passed the file + * descriptor to QEMU, so we cannot know for sure whether it + * refers to a plain file or a socket. Let it through anyway. + */ + if (addr->transport == MIGRATION_ADDRESS_TYPE_SOCKET) { + return addr->u.socket.type == SOCKET_ADDRESS_TYPE_FD; + } + + return false; +} + static bool migration_channels_and_transport_compatible(MigrationAddress *addr, Error **errp) { + if (migration_needs_seekable_channel() && + !transport_supports_seeking(addr)) { + error_setg(errp, "Migration requires seekable transport (e.g. file)"); + return false; + } + if (migration_needs_multiple_sockets() && !transport_supports_multi_channels(addr)) { error_setg(errp, "Migration requires multi-channel URIs (e.g. tcp)"); -- 2.44.0
