[PATCH 05/11] migration: Drop save_live_complete_postcopy hook

[Peter Xu <peterx@redhat.com>]

The hook is only defined in two vmstate users ("ram" and "block dirty
bitmap"), meanwhile both of them define the hook exactly the same as the
precopy version.  Hence, this postcopy version isn't needed.

No functional change intended.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 include/migration/register.h   | 24 ++++++++----------------
 migration/block-dirty-bitmap.c |  1 -
 migration/ram.c                |  1 -
 migration/savevm.c             |  9 ++++-----
 4 files changed, 12 insertions(+), 23 deletions(-)

diff --git a/include/migration/register.h b/include/migration/register.h
index b79dc81b8d..e022195785 100644
--- a/include/migration/register.h
+++ b/include/migration/register.h
@@ -77,26 +77,18 @@ typedef struct SaveVMHandlers {
      */
     void (*save_cleanup)(void *opaque);
 
-    /**
-     * @save_live_complete_postcopy
-     *
-     * Called at the end of postcopy for all postcopyable devices.
-     *
-     * @f: QEMUFile where to send the data
-     * @opaque: data pointer passed to register_savevm_live()
-     *
-     * Returns zero to indicate success and negative for error
-     */
-    int (*save_live_complete_postcopy)(QEMUFile *f, void *opaque);
-
     /**
      * @save_live_complete_precopy
      *
      * Transmits the last section for the device containing any
-     * remaining data at the end of a precopy phase. When postcopy is
-     * enabled, devices that support postcopy will skip this step,
-     * where the final data will be flushed at the end of postcopy via
-     * @save_live_complete_postcopy instead.
+     * remaining data at the end phase of migration.
+     *
+     * For precopy, this will be invoked _during_ the switchover phase
+     * after source VM is stopped.
+     *
+     * For postcopy, this will be invoked _after_ the switchover phase
+     * (except some very unusual cases, like PMEM ramblocks), while
+     * destination VM can be running.
      *
      * @f: QEMUFile where to send the data
      * @opaque: data pointer passed to register_savevm_live()
diff --git a/migration/block-dirty-bitmap.c b/migration/block-dirty-bitmap.c
index f2c352d4a7..6ee3c32a76 100644
--- a/migration/block-dirty-bitmap.c
+++ b/migration/block-dirty-bitmap.c
@@ -1248,7 +1248,6 @@ static bool dirty_bitmap_has_postcopy(void *opaque)
 
 static SaveVMHandlers savevm_dirty_bitmap_handlers = {
     .save_setup = dirty_bitmap_save_setup,
-    .save_live_complete_postcopy = dirty_bitmap_save_complete,
     .save_live_complete_precopy = dirty_bitmap_save_complete,
     .has_postcopy = dirty_bitmap_has_postcopy,
     .state_pending_exact = dirty_bitmap_state_pending,
diff --git a/migration/ram.c b/migration/ram.c
index fd8d83b63c..8b43b9e1e8 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -4545,7 +4545,6 @@ void postcopy_preempt_shutdown_file(MigrationState *s)
 static SaveVMHandlers savevm_ram_handlers = {
     .save_setup = ram_save_setup,
     .save_live_iterate = ram_save_iterate,
-    .save_live_complete_postcopy = ram_save_complete,
     .save_live_complete_precopy = ram_save_complete,
     .has_postcopy = ram_has_postcopy,
     .state_pending_exact = ram_state_pending_exact,
diff --git a/migration/savevm.c b/migration/savevm.c
index 006514c3e3..26d32eb5a7 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1485,9 +1485,8 @@ bool should_send_vmdesc(void)
 }
 
 /*
- * Calls the save_live_complete_postcopy methods
- * causing the last few pages to be sent immediately and doing any associated
- * cleanup.
+ * Complete saving any postcopy-able devices.
+ *
  * Note postcopy also calls qemu_savevm_state_complete_precopy to complete
  * all the other devices, but that happens at the point we switch to postcopy.
  */
@@ -1497,7 +1496,7 @@ void qemu_savevm_state_complete_postcopy(QEMUFile *f)
     int ret;
 
     QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
-        if (!se->ops || !se->ops->save_live_complete_postcopy) {
+        if (!se->ops || !se->ops->save_live_complete_precopy) {
             continue;
         }
         if (se->ops->is_active) {
@@ -1510,7 +1509,7 @@ void qemu_savevm_state_complete_postcopy(QEMUFile *f)
         qemu_put_byte(f, QEMU_VM_SECTION_END);
         qemu_put_be32(f, se->section_id);
 
-        ret = se->ops->save_live_complete_postcopy(f, se->opaque);
+        ret = se->ops->save_live_complete_precopy(f, se->opaque);
         trace_savevm_section_end(se->idstr, se->section_id, ret);
         save_section_footer(f, se);
         if (ret < 0) {
-- 
2.49.0