@@ -95,6 +95,9 @@ enum mig_rp_message_type {
MIG_RP_MSG_MAX
};
+/* Migration channel types */
+enum { CH_MAIN, CH_MULTIFD, CH_POSTCOPY };
+
/* When we add fault tolerance, we could have several
migrations at once. For now we don't need to add
dynamic creation of migration */
@@ -985,28 +988,19 @@ void migration_fd_process_incoming(QEMUFile *f)
migration_incoming_process();
}
-/*
- * Returns true when we want to start a new incoming migration process,
- * false otherwise.
- */
-static bool migration_should_start_incoming(bool main_channel)
+static bool migration_has_main_and_multifd_channels(void)
{
- /* Multifd doesn't start unless all channels are established */
- if (migrate_multifd()) {
- return migration_has_all_channels();
+ MigrationIncomingState *mis = migration_incoming_get_current();
+ if (!mis->from_src_file) {
+ /* main channel not established */
+ return false;
}
- /* Preempt channel only starts when the main channel is created */
- if (migrate_postcopy_preempt()) {
- return main_channel;
+ if (migrate_multifd() && !multifd_recv_all_channels_created()) {
+ return false;
}
- /*
- * For all the rest types of migration, we should only reach here when
- * it's the main channel that's being created, and we should always
- * proceed with this channel.
- */
- assert(main_channel);
+ /* main and all multifd channels are established */
return true;
}
@@ -1015,59 +1009,84 @@ void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
MigrationIncomingState *mis = migration_incoming_get_current();
Error *local_err = NULL;
QEMUFile *f;
- bool default_channel = true;
+ uint8_t channel;
uint32_t channel_magic = 0;
int ret = 0;
- if (migrate_multifd() && !migrate_mapped_ram() &&
- !migrate_postcopy_ram() &&
- qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_READ_MSG_PEEK)) {
- /*
- * With multiple channels, it is possible that we receive channels
- * out of order on destination side, causing incorrect mapping of
- * source channels on destination side. Check channel MAGIC to
- * decide type of channel. Please note this is best effort, postcopy
- * preempt channel does not send any magic number so avoid it for
- * postcopy live migration. Also tls live migration already does
- * tls handshake while initializing main channel so with tls this
- * issue is not possible.
- */
- ret = migration_channel_read_peek(ioc, (void *)&channel_magic,
- sizeof(channel_magic), errp);
+ if (!migration_has_main_and_multifd_channels()) {
+ if (qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_READ_MSG_PEEK)) {
+ /*
+ * With multiple channels, it is possible that we receive channels
+ * out of order on destination side, causing incorrect mapping of
+ * source channels on destination side. Check channel MAGIC to
+ * decide type of channel. Please note this is best effort,
+ * postcopy preempt channel does not send any magic number so
+ * avoid it for postcopy live migration. Also tls live migration
+ * already does tls handshake while initializing main channel so
+ * with tls this issue is not possible.
+ */
+ ret = migration_channel_read_peek(ioc, (void *)&channel_magic,
+ sizeof(channel_magic), errp);
+ if (ret != 0) {
+ return;
+ }
- if (ret != 0) {
+ channel_magic = be32_to_cpu(channel_magic);
+ if (channel_magic == QEMU_VM_FILE_MAGIC) {
+ channel = CH_MAIN;
+ } else if (channel_magic == MULTIFD_MAGIC) {
+ channel = CH_MULTIFD;
+ } else if (!mis->from_src_file &&
+ mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
+ /* reconnect main channel for postcopy recovery */
+ channel = CH_MAIN;
+ } else {
+ error_setg(errp, "unknown channel magic: %u", channel_magic);
+ return;
+ }
+ } else if (mis->from_src_file && migrate_multifd()) {
+ /*
+ * Non-peekable channels like tls/file are processed as
+ * multifd channels when multifd is enabled.
+ */
+ channel = CH_MULTIFD;
+ } else if (!mis->from_src_file) {
+ channel = CH_MAIN;
+ } else {
+ error_setg(errp, "non-peekable channel used without multifd");
return;
}
-
- default_channel = (channel_magic == cpu_to_be32(QEMU_VM_FILE_MAGIC));
+ } else if (mis->from_src_file) {
+ channel = CH_POSTCOPY;
} else {
- default_channel = !mis->from_src_file;
+ channel = CH_MAIN;
}
if (multifd_recv_setup(errp) != 0) {
return;
}
- if (default_channel) {
+ if (channel == CH_MAIN) {
f = qemu_file_new_input(ioc);
migration_incoming_setup(f);
- } else {
+ } else if (channel == CH_MULTIFD) {
/* Multiple connections */
- assert(migration_needs_multiple_sockets());
if (migrate_multifd()) {
multifd_recv_new_channel(ioc, &local_err);
- } else {
- assert(migrate_postcopy_preempt());
- f = qemu_file_new_input(ioc);
- postcopy_preempt_new_channel(mis, f);
}
if (local_err) {
error_propagate(errp, local_err);
return;
}
+ } else if (channel == CH_POSTCOPY) {
+ assert(migrate_postcopy_preempt());
+ assert(!mis->postcopy_qemufile_dst);
+ f = qemu_file_new_input(ioc);
+ postcopy_preempt_new_channel(mis, f);
+ return;
}
- if (migration_should_start_incoming(default_channel)) {
+ if (migration_has_main_and_multifd_channels()) {
/* If it's a recovery, we're done */
if (postcopy_try_recover()) {
return;
@@ -1084,20 +1103,15 @@ void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
*/
bool migration_has_all_channels(void)
{
+ if (!migration_has_main_and_multifd_channels()) {
+ return false;
+ }
+
MigrationIncomingState *mis = migration_incoming_get_current();
-
- if (!mis->from_src_file) {
+ if (migrate_postcopy_preempt() && !mis->postcopy_qemufile_dst) {
return false;
}
- if (migrate_multifd()) {
- return multifd_recv_all_channels_created();
- }
-
- if (migrate_postcopy_preempt()) {
- return mis->postcopy_qemufile_dst != NULL;
- }
-
return true;
}