Use the component callbacks; prepare, commit, abort, and clean.
NB: prepare is only called when the job has not yet failed;
and abort can be called after prepare.
complete -> prepare -> abort -> clean
complete -> abort -> clean
Signed-off-by: John Snow <js...@redhat.com>
---
block/commit.c | 94 +++++++++++++++++++++++++++++++++++++---------------------
1 file changed, 61 insertions(+), 33 deletions(-)
diff --git a/block/commit.c b/block/commit.c
index 1a4a56795f..6673a0544e 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -35,7 +35,9 @@ typedef struct CommitBlockJob {
BlockJob common;
BlockDriverState *commit_top_bs;
BlockBackend *top;
+ BlockDriverState *top_bs;
BlockBackend *base;
+ BlockDriverState *base_bs;
BlockdevOnError on_error;
int base_flags;
char *backing_file_str;
@@ -71,37 +73,37 @@ static int coroutine_fn commit_populate(BlockBackend *bs,
BlockBackend *base,
static void commit_exit(Job *job)
{
CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
- BlockJob *bjob = &s->common;
- BlockDriverState *top = blk_bs(s->top);
- BlockDriverState *base = blk_bs(s->base);
- BlockDriverState *commit_top_bs = s->commit_top_bs;
- int ret = job->ret;
- bool remove_commit_top_bs = false;
+
+ s->top_bs = blk_bs(s->top);
+ s->base_bs = blk_bs(s->base);
/* Make sure commit_top_bs and top stay around until bdrv_replace_node() */
- bdrv_ref(top);
- bdrv_ref(commit_top_bs);
+ bdrv_ref(s->top_bs);
+ bdrv_ref(s->commit_top_bs);
+}
- /* Remove base node parent that still uses BLK_PERM_WRITE/RESIZE before
- * the normal backing chain can be restored. */
- blk_unref(s->base);
+static int commit_prepare(Job *job)
+{
+ CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
- if (!job_is_cancelled(job) && ret == 0) {
- /* success */
- ret = bdrv_drop_intermediate(s->commit_top_bs, base,
- s->backing_file_str);
- } else {
- /* XXX Can (or should) we somehow keep 'consistent read' blocked even
- * after the failed/cancelled commit job is gone? If we already wrote
- * something to base, the intermediate images aren't valid any more. */
- remove_commit_top_bs = true;
- }
+ /* Remove base node parent that still uses BLK_PERM_WRITE/RESIZE before
+ * the normal backing chain can be restored. */
+ blk_unref(s->base);
+ s->base = NULL;
+
+ return bdrv_drop_intermediate(s->commit_top_bs, s->base_bs,
+ s->backing_file_str);
+}
+
+static void commit_exit_common(Job *job)
+{
+ CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
/* restore base open flags here if appropriate (e.g., change the base back
* to r/o). These reopens do not need to be atomic, since we won't abort
* even on failure here */
- if (s->base_flags != bdrv_get_flags(base)) {
- bdrv_reopen(base, s->base_flags, NULL);
+ if (s->base_flags != bdrv_get_flags(s->base_bs)) {
+ bdrv_reopen(s->base_bs, s->base_flags, NULL);
}
g_free(s->backing_file_str);
blk_unref(s->top);
@@ -110,21 +112,43 @@ static void commit_exit(Job *job)
* job_finish_sync()), job_completed() won't free it and therefore the
* blockers on the intermediate nodes remain. This would cause
* bdrv_set_backing_hd() to fail. */
- block_job_remove_all_bdrv(bjob);
+ block_job_remove_all_bdrv(&s->common);
+}
+
+static void commit_commit(Job *job)
+{
+ commit_exit_common(job);
+}
+
+static void commit_abort(Job *job)
+{
+ CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
+
+ if (s->base) {
+ blk_unref(s->base);
+ }
+
+ commit_exit_common(job);
+
+ /* XXX Can (or should) we somehow keep 'consistent read' blocked even
+ * after the failed/cancelled commit job is gone? If we already wrote
+ * something to base, the intermediate images aren't valid any more. */
/* If bdrv_drop_intermediate() didn't already do that, remove the commit
* filter driver from the backing chain. Do this as the final step so that
* the 'consistent read' permission can be granted. */
- if (remove_commit_top_bs) {
- bdrv_child_try_set_perm(commit_top_bs->backing, 0, BLK_PERM_ALL,
- &error_abort);
- bdrv_replace_node(commit_top_bs, backing_bs(commit_top_bs),
- &error_abort);
- }
+ bdrv_child_try_set_perm(s->commit_top_bs->backing, 0, BLK_PERM_ALL,
+ &error_abort);
+ bdrv_replace_node(s->commit_top_bs, backing_bs(s->commit_top_bs),
+ &error_abort);
+}
- bdrv_unref(commit_top_bs);
- bdrv_unref(top);
- job->ret = ret;
+static void commit_clean(Job *job)
+{
+ CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
+
+ bdrv_unref(s->commit_top_bs);
+ bdrv_unref(s->top_bs);
}
static int coroutine_fn commit_run(Job *job)
@@ -214,6 +238,10 @@ static const BlockJobDriver commit_job_driver = {
.drain = block_job_drain,
.start = commit_run,
.exit = commit_exit,
+ .prepare = commit_prepare,
+ .commit = commit_commit,
+ .abort = commit_abort,
+ .clean = commit_clean
},
};
--
2.14.4
