[PATCH 5/8] qemu: migration: Don't attempt to fall back to old-style storage migration

[Peter Krempa]

QEMU supported the NBD server required for the new-style migration for a
long time already and when coupled with -blockdev the old style
migration doesn't even work, thus remove support for it.

This patch modifies the code to check that the destination returned data
for the NBD migration and returns an error if it did not and deletes the
fallback code paths which would not work.

Signed-off-by: Peter Krempa <pkrempa at redhat.com>
---
 src/qemu/qemu_migration.c | 45 +++++++++++++++++----------------------
 1 file changed, 19 insertions(+), 26 deletions(-)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 995364da02..7dc593d49f 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -4817,35 +4817,28 @@ qemuMigrationSrcRun(virQEMUDriver *driver,
     }

     if (storageMigration) {
-        if (mig->nbd) {
-            const char *host = "";
-            const char *tlsHostname = qemuMigrationParamsGetTLSHostname(migParams);
+        const char *host = "";
+        const char *tlsHostname = qemuMigrationParamsGetTLSHostname(migParams);

-            if (spec->destType == MIGRATION_DEST_HOST ||
-                spec->destType == MIGRATION_DEST_CONNECT_HOST) {
-                host = spec->dest.host.name;
-            }
-
-            if (qemuMigrationSrcNBDStorageCopy(driver, vm, mig,
-                                               host,
-                                               priv->migMaxBandwidth,
-                                               nmigrate_disks,
-                                               migrate_disks,
-                                               dconn, tlsAlias, tlsHostname,
-                                               nbdURI, flags) < 0) {
-                goto error;
-            }
-        } else {
-            /* Destination doesn't support NBD server.
-             * Fall back to previous implementation. */
-            VIR_DEBUG("Destination doesn't support NBD server "
-                      "Falling back to previous implementation.");
+        if (!mig->nbd) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                           _("migration of non-shared disks requested but NBD is not set up"));
+            goto error;
+        }

-            if (flags & VIR_MIGRATE_NON_SHARED_DISK)
-                migrate_flags |= QEMU_MONITOR_MIGRATE_NON_SHARED_DISK;
+        if (spec->destType == MIGRATION_DEST_HOST ||
+            spec->destType == MIGRATION_DEST_CONNECT_HOST) {
+            host = spec->dest.host.name;
+        }

-            if (flags & VIR_MIGRATE_NON_SHARED_INC)
-                migrate_flags |= QEMU_MONITOR_MIGRATE_NON_SHARED_INC;
+        if (qemuMigrationSrcNBDStorageCopy(driver, vm, mig,
+                                           host,
+                                           priv->migMaxBandwidth,
+                                           nmigrate_disks,
+                                           migrate_disks,
+                                           dconn, tlsAlias, tlsHostname,
+                                           nbdURI, flags) < 0) {
+            goto error;
         }
     }

-- 
2.37.1