migration: make *save_live return errors

Make *save_live() return negative values when there is one error, and
updates all callers to check for the error.

Signed-off-by: Juan Quintela <quintela@redhat.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/savevm.c b/savevm.c
index 5b340b695f..9e9c7835a0 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1534,7 +1534,11 @@ int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable,
         qemu_put_be32(f, se->instance_id);
         qemu_put_be32(f, se->version_id);
 
-        se->save_live_state(mon, f, QEMU_VM_SECTION_START, se->opaque);
+        ret = se->save_live_state(mon, f, QEMU_VM_SECTION_START, se->opaque);
+        if (ret < 0) {
+            qemu_savevm_state_cancel(mon, f);
+            return ret;
+        }
     }
     ret = qemu_file_get_error(f);
     if (ret != 0) {
@@ -1565,7 +1569,7 @@ int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f)
         qemu_put_be32(f, se->section_id);
 
         ret = se->save_live_state(mon, f, QEMU_VM_SECTION_PART, se->opaque);
-        if (!ret) {
+        if (ret <= 0) {
             /* Do not proceed to the next vmstate before this one reported
                completion of the current stage. This serializes the migration
                and reduces the probability that a faster changing state is
@@ -1586,6 +1590,7 @@ int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f)
 int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f)
 {
     SaveStateEntry *se;
+    int ret;
 
     cpu_synchronize_all_states();
 
@@ -1597,7 +1602,10 @@ int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f)
         qemu_put_byte(f, QEMU_VM_SECTION_END);
         qemu_put_be32(f, se->section_id);
 
-        se->save_live_state(mon, f, QEMU_VM_SECTION_END, se->opaque);
+        ret = se->save_live_state(mon, f, QEMU_VM_SECTION_END, se->opaque);
+        if (ret < 0) {
+            return ret;
+        }
     }
 
     QTAILQ_FOREACH(se, &savevm_handlers, entry) {