On Wed, Aug 29, 2018 at 09:57:30PM -0400, John Snow wrote:
> Change the manual deferment to mirror_exit into the implicit
> callback to job_exit and the mirror_exit callback.
>
> This does change the order of some bdrv_unref calls and job_completed,
> but thanks to the new context in which we call .exit, this is safe to
> defer the possible flushing of any nodes to the job_finalize_single
> cleanup stage.
>
> Signed-off-by: John Snow
Reviewed-by: Jeff Cody
> ---
> block/mirror.c | 29 +++--
> 1 file changed, 11 insertions(+), 18 deletions(-)
>
> diff --git a/block/mirror.c b/block/mirror.c
> index be5dc6b7b0..b8941db6c1 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -607,26 +607,22 @@ static void mirror_wait_for_all_io(MirrorBlockJob *s)
> }
> }
>
> -typedef struct {
> -int ret;
> -} MirrorExitData;
> -
> -static void mirror_exit(Job *job, void *opaque)
> +static void mirror_exit(Job *job)
> {
> MirrorBlockJob *s = container_of(job, MirrorBlockJob, common.job);
> BlockJob *bjob = &s->common;
> -MirrorExitData *data = opaque;
> MirrorBDSOpaque *bs_opaque = s->mirror_top_bs->opaque;
> AioContext *replace_aio_context = NULL;
> BlockDriverState *src = s->mirror_top_bs->backing->bs;
> BlockDriverState *target_bs = blk_bs(s->target);
> BlockDriverState *mirror_top_bs = s->mirror_top_bs;
> Error *local_err = NULL;
> +int ret = job->ret;
>
> bdrv_release_dirty_bitmap(src, s->dirty_bitmap);
>
> -/* Make sure that the source BDS doesn't go away before we called
> - * job_completed(). */
> +/* Make sure that the source BDS doesn't go away during
> bdrv_replace_node,
> + * before we can call bdrv_drained_end */
> bdrv_ref(src);
> bdrv_ref(mirror_top_bs);
> bdrv_ref(target_bs);
> @@ -652,7 +648,7 @@ static void mirror_exit(Job *job, void *opaque)
> bdrv_set_backing_hd(target_bs, backing, &local_err);
> if (local_err) {
> error_report_err(local_err);
> -data->ret = -EPERM;
> +ret = -EPERM;
> }
> }
> }
> @@ -662,7 +658,7 @@ static void mirror_exit(Job *job, void *opaque)
> aio_context_acquire(replace_aio_context);
> }
>
> -if (s->should_complete && data->ret == 0) {
> +if (s->should_complete && ret == 0) {
> BlockDriverState *to_replace = src;
> if (s->to_replace) {
> to_replace = s->to_replace;
> @@ -679,7 +675,7 @@ static void mirror_exit(Job *job, void *opaque)
> bdrv_drained_end(target_bs);
> if (local_err) {
> error_report_err(local_err);
> -data->ret = -EPERM;
> +ret = -EPERM;
> }
> }
> if (s->to_replace) {
> @@ -710,12 +706,12 @@ static void mirror_exit(Job *job, void *opaque)
> blk_insert_bs(bjob->blk, mirror_top_bs, &error_abort);
>
> bs_opaque->job = NULL;
> -job_completed(job, data->ret);
>
> -g_free(data);
> bdrv_drained_end(src);
> bdrv_unref(mirror_top_bs);
> bdrv_unref(src);
> +
> +job->ret = ret;
> }
>
> static void mirror_throttle(MirrorBlockJob *s)
> @@ -815,7 +811,6 @@ static int mirror_flush(MirrorBlockJob *s)
> static int coroutine_fn mirror_run(Job *job, Error **errp)
> {
> MirrorBlockJob *s = container_of(job, MirrorBlockJob, common.job);
> -MirrorExitData *data;
> BlockDriverState *bs = s->mirror_top_bs->backing->bs;
> BlockDriverState *target_bs = blk_bs(s->target);
> bool need_drain = true;
> @@ -1035,14 +1030,10 @@ immediate_exit:
> g_free(s->in_flight_bitmap);
> bdrv_dirty_iter_free(s->dbi);
>
> -data = g_malloc(sizeof(*data));
> -data->ret = ret;
> -
> if (need_drain) {
> bdrv_drained_begin(bs);
> }
>
> -job_defer_to_main_loop(&s->common.job, mirror_exit, data);
> return ret;
> }
>
> @@ -1141,6 +1132,7 @@ static const BlockJobDriver mirror_job_driver = {
> .user_resume= block_job_user_resume,
> .drain = block_job_drain,
> .run= mirror_run,
> +.exit = mirror_exit,
> .pause = mirror_pause,
> .complete = mirror_complete,
> },
> @@ -1157,6 +1149,7 @@ static const BlockJobDriver commit_active_job_driver = {
> .user_resume= block_job_user_resume,
> .drain = block_job_drain,
> .run= mirror_run,
> +.exit = mirror_exit,
> .pause = mirror_pause,
> .complete = mirror_complete,
> },
> --
> 2.14.4
>
