If active is top, it will be mirrored to base, (with block/mirror.c
code), then the image is switched when user completes the block job.
Signed-off-by: Fam Zheng <f...@redhat.com>
---
blockdev.c | 42 ++++++++++++++++++++++++++++++++++++++++--
1 file changed, 40 insertions(+), 2 deletions(-)
diff --git a/blockdev.c b/blockdev.c
index 032913e..f730e6f 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1663,6 +1663,30 @@ void qmp_block_stream(const char *device, bool has_base,
trace_qmp_block_stream(bs, bs->job);
}
+typedef struct {
+ BlockDriverState *bs;
+ BlockDriverState *base;
+} commit_active_info_t;
+
+static void commit_active_cb(void *_info, int ret)
+{
+ commit_active_info_t *info = _info;
+ BlockDriverState *p;
+ assert(info->bs);
+ assert(info->base);
+ assert(info->base->backing_hd);
+ if (!ret) {
+ /* Mirror code already swapped bs and base, we drop the bs loop chain
+ * formed by the swap: break the loop chain, trigger the chain unref.
+ */
+ p = info->base->backing_hd;
+ info->base->backing_hd = NULL;
+ bdrv_unref(p);
+ }
+ block_job_cb(info->bs, ret);
+ g_free(info);
+}
+
void qmp_block_commit(const char *device,
bool has_base, const char *base, const char *top,
bool has_speed, int64_t speed,
@@ -1710,8 +1734,22 @@ void qmp_block_commit(const char *device,
return;
}
- commit_start(bs, base_bs, top_bs, speed, on_error, block_job_cb, bs,
- &local_err);
+ if (top_bs == bs) {
+ commit_active_info_t *info = g_malloc(sizeof(commit_active_info_t));
+ info->bs = bs;
+ info->base = base_bs;
+ if (bdrv_reopen(base_bs, bs->open_flags, &local_err)) {
+ error_propagate(errp, local_err);
+ return;
+ }
+ bdrv_ref(base_bs);
+ mirror_start(bs, base_bs, speed, 0, 0, MIRROR_SYNC_MODE_COMMON,
+ on_error, on_error, true,
+ commit_active_cb, info, &local_err);
+ } else {
+ commit_start(bs, base_bs, top_bs, speed, on_error, block_job_cb, bs,
+ &local_err);
+ }
if (local_err != NULL) {
error_propagate(errp, local_err);
return;
--
1.8.3.1
