[Qemu-devel] [PATCH 43/46] postcopy: Wire up loadvm_postcopy_ram_handle_{run, end} commands

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Wire up more of the handlers for the commands on the destination side,
in particular loadvm_postcopy_ram_handle_run now has enough to start the
guest running.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 savevm.c | 47 ++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 42 insertions(+), 5 deletions(-)

diff --git a/savevm.c b/savevm.c
index f4907db..8c79d37 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1341,6 +1341,8 @@ static int loadvm_postcopy_ram_handle_listen(MigrationIncomingState *mis)
 /* After all discards we can start running and asking for pages */
 static int loadvm_postcopy_ram_handle_run(MigrationIncomingState *mis)
 {
+    Error *local_err = NULL;
+
     DPRINTF("%s", __func__);
     if (mis->postcopy_ram_state != POSTCOPY_RAM_INCOMING_LISTENING) {
         error_report("CMD_POSTCOPY_RAM_RUN in wrong postcopy state (%d)",
@@ -1349,14 +1351,39 @@ static int loadvm_postcopy_ram_handle_run(MigrationIncomingState *mis)
     }
 
     mis->postcopy_ram_state = POSTCOPY_RAM_INCOMING_RUNNING;
+
+    /* TODO we should move all of this lot into postcopy_ram.c or a shared code
+     * in migration.c
+     */
+    cpu_synchronize_all_post_init();
+
+    qemu_announce_self();
+    bdrv_clear_incoming_migration_all();
+
+    /* Make sure all file formats flush their mutable metadata */
+    bdrv_invalidate_cache_all(&local_err);
+    if (local_err) {
+        qerror_report_err(local_err);
+        error_free(local_err);
+        return -1;
+    }
+
+    DPRINTF("loadvm_postcopy_ram_handle_run: cpu_synchronize_all_post_init");
+    cpu_synchronize_all_post_init();
+
+    DPRINTF("loadvm_postcopy_ram_handle_run: vm_start");
     /* Hold onto your hats, starting the CPU */
     vm_start();
 
-    return 0;
+    return LOADVM_EXITCODE_QUITLOOP;
 }
 
-/* The end - with a byte from the source which can tell us to fail. */
-static int loadvm_postcopy_ram_handle_end(MigrationIncomingState *mis)
+/* The end - with a byte from the source which can tell us to fail.
+ * The source sends this either if there is a failure, or if it believes it's
+ * sent everything
+ */
+static int loadvm_postcopy_ram_handle_end(MigrationIncomingState *mis,
+                                          uint8_t status)
 {
     DPRINTF("%s", __func__);
     if (mis->postcopy_ram_state == POSTCOPY_RAM_INCOMING_NONE) {
@@ -1364,7 +1391,17 @@ static int loadvm_postcopy_ram_handle_end(MigrationIncomingState *mis)
                      mis->postcopy_ram_state);
         return -1;
     }
-    return -1; /* TODO - expecting 1 byte good/fail */
+
+    DPRINTF("loadvm_postcopy_ram_handle_end status=%d", status);
+
+    /* TODO: Give up on non-0 status
+     * TODO: If 0 status, check we've received everything (all outstanding
+     * requests should already have been completed)
+     * TODO: Indicate completion back to source
+     */
+    /* TODO: Or should this be none? */
+    mis->postcopy_ram_state = POSTCOPY_RAM_INCOMING_END;
+    return LOADVM_EXITCODE_QUITLOOP;
 }
 
 static int loadvm_process_command_simple_lencheck(const char *name,
@@ -1505,7 +1542,7 @@ static int loadvm_process_command(QEMUFile *f,
                                                    len, 1)) {
             return -1;
         }
-        return loadvm_postcopy_ram_handle_end(mis);
+        return loadvm_postcopy_ram_handle_end(mis, qemu_get_byte(f));
 
     default:
         error_report("VM_COMMAND 0x%x unknown (len 0x%x)", com, len);
-- 
1.9.3