[Qemu-block] [PATCH for-2.6 1/3] mirror: Extract mirror_replace

[Fam Zheng]

Move the BDS replacing code to a separate function so that it can be
used in the next patch. A new field "should_replace" is added and set to
true so the function is always called for now.

Signed-off-by: Fam Zheng <address@hidden>
---
 block/mirror.c | 36 +++++++++++++++++++++++-------------
 1 file changed, 23 insertions(+), 13 deletions(-)

diff --git a/block/mirror.c b/block/mirror.c
index d56e30e..6c3fe43 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -441,26 +441,20 @@ static void mirror_drain(MirrorBlockJob *s)
 }
 
 typedef struct {
+    bool should_replace;
     int ret;
 } MirrorExitData;
 
-static void mirror_exit(BlockJob *job, void *opaque)
+static void mirror_replace(MirrorBlockJob *s, int *ret)
 {
-    MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
-    MirrorExitData *data = opaque;
     AioContext *replace_aio_context = NULL;
-    BlockDriverState *src = s->common.bs;
-
-    /* Make sure that the source BDS doesn't go away before we called
-     * block_job_completed(). */
-    bdrv_ref(src);
 
     if (s->to_replace) {
         replace_aio_context = bdrv_get_aio_context(s->to_replace);
         aio_context_acquire(replace_aio_context);
     }
 
-    if (s->should_complete && data->ret == 0) {
+    if (s->should_complete && *ret == 0) {
         BlockDriverState *to_replace = s->common.bs;
         if (s->to_replace) {
             to_replace = s->to_replace;
@@ -470,7 +464,7 @@ static void mirror_exit(BlockJob *job, void *opaque)
          * nodes could have been newly attached to a BlockBackend. */
         if (to_replace->blk && s->target->blk) {
             error_report("block job: Can't create node with two 
BlockBackends");
-            data->ret = -EINVAL;
+            *ret = -EINVAL;
             goto out;
         }
 
@@ -481,14 +475,29 @@ static void mirror_exit(BlockJob *job, void *opaque)
     }
 
 out:
+    if (replace_aio_context) {
+        aio_context_release(replace_aio_context);
+    }
+}
+
+static void mirror_exit(BlockJob *job, void *opaque)
+{
+    MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
+    MirrorExitData *data = opaque;
+    BlockDriverState *src = s->common.bs;
+
+    /* Make sure that the source BDS doesn't go away before we called
+     * block_job_completed(). */
+    bdrv_ref(src);
+
+    if (data->should_replace) {
+        mirror_replace(s, &data->ret);
+    }
     if (s->to_replace) {
         bdrv_op_unblock_all(s->to_replace, s->replace_blocker);
         error_free(s->replace_blocker);
         bdrv_unref(s->to_replace);
     }
-    if (replace_aio_context) {
-        aio_context_release(replace_aio_context);
-    }
     g_free(s->replaces);
     bdrv_op_unblock_all(s->target, s->common.blocker);
     bdrv_unref(s->target);
@@ -713,6 +722,7 @@ immediate_exit:
 
     data = g_malloc(sizeof(*data));
     data->ret = ret;
+    data->should_replace = true;
     /* Before we switch to target in mirror_exit, make sure data doesn't
      * change. */
     bdrv_drained_begin(s->common.bs);
-- 
2.8.0