[Qemu-block] [PATCH RFC 4/7] replication: Split out backup_do_checkpoint() from secondary_do_checkpoint()

[zhanghailiang]

The helper backup_do_checkpoint() will be used for primary related
codes. Here we split it out from secondary_do_checkpoint().

Besides, it is unnecessary to call backup_do_checkpoint() in
replication starting and normally stop replication path.
We only need call it while do real checkpointing.

Signed-off-by: zhanghailiang <address@hidden>
---
 block/replication.c | 36 +++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

diff --git a/block/replication.c b/block/replication.c
index 2a2fdb2..d687ffc 100644
--- a/block/replication.c
+++ b/block/replication.c
@@ -320,20 +320,8 @@ static bool 
replication_recurse_is_first_non_filter(BlockDriverState *bs,
 
 static void secondary_do_checkpoint(BDRVReplicationState *s, Error **errp)
 {
-    Error *local_err = NULL;
     int ret;
 
-    if (!s->secondary_disk->bs->job) {
-        error_setg(errp, "Backup job was cancelled unexpectedly");
-        return;
-    }
-
-    backup_do_checkpoint(s->secondary_disk->bs->job, &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
-        return;
-    }
-
     ret = s->active_disk->bs->drv->bdrv_make_empty(s->active_disk->bs);
     if (ret < 0) {
         error_setg(errp, "Cannot make active disk empty");
@@ -539,6 +527,8 @@ static void replication_start(ReplicationState *rs, 
ReplicationMode mode,
             aio_context_release(aio_context);
             return;
         }
+
+        secondary_do_checkpoint(s, errp);
         break;
     default:
         aio_context_release(aio_context);
@@ -547,10 +537,6 @@ static void replication_start(ReplicationState *rs, 
ReplicationMode mode,
 
     s->replication_state = BLOCK_REPLICATION_RUNNING;
 
-    if (s->mode == REPLICATION_MODE_SECONDARY) {
-        secondary_do_checkpoint(s, errp);
-    }
-
     s->error = 0;
     aio_context_release(aio_context);
 }
@@ -560,13 +546,29 @@ static void replication_do_checkpoint(ReplicationState 
*rs, Error **errp)
     BlockDriverState *bs = rs->opaque;
     BDRVReplicationState *s;
     AioContext *aio_context;
+    Error *local_err = NULL;
 
     aio_context = bdrv_get_aio_context(bs);
     aio_context_acquire(aio_context);
     s = bs->opaque;
 
-    if (s->mode == REPLICATION_MODE_SECONDARY) {
+    switch (s->mode) {
+    case REPLICATION_MODE_PRIMARY:
+        break;
+    case REPLICATION_MODE_SECONDARY:
+        if (!s->secondary_disk->bs->job) {
+            error_setg(errp, "Backup job was cancelled unexpectedly");
+            break;
+        }
+        backup_do_checkpoint(s->secondary_disk->bs->job, &local_err);
+        if (local_err) {
+            error_propagate(errp, local_err);
+            break;
+        }
         secondary_do_checkpoint(s, errp);
+        break;
+    default:
+        abort();
     }
     aio_context_release(aio_context);
 }
-- 
1.8.3.1