Instead of draining additional nodes in each job code, let's do it in common block_job_drain, draining just all job's children. BlockJobDriver.drain becomes unused, so, drop it at all.
It's also a first step to finally get rid of blockjob->blk. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> --- v4: keep ref/unref around job nodes draining [John, Max] v3: just resend, as I've some auto returned mails and not sure that v2 reached recipients. v2: apply Max's suggestions: - drop BlockJobDriver.drain - do firtly loop of bdrv_drained_begin and then separate loop of bdrv_drained_end. Hmm, a question here: should I call bdrv_drained_end in reverse order? Or it's OK as is? include/block/blockjob_int.h | 11 ----------- block/backup.c | 18 +----------------- block/mirror.c | 26 +++----------------------- blockjob.c | 22 +++++++++++++++++----- 4 files changed, 21 insertions(+), 56 deletions(-) diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h index e4a318dd15..e1abf4ee85 100644 --- a/include/block/blockjob_int.h +++ b/include/block/blockjob_int.h @@ -52,17 +52,6 @@ struct BlockJobDriver { * besides job->blk to the new AioContext. */ void (*attached_aio_context)(BlockJob *job, AioContext *new_context); - - /* - * If the callback is not NULL, it will be invoked when the job has to be - * synchronously cancelled or completed; it should drain BlockDriverStates - * as required to ensure progress. - * - * Block jobs must use the default implementation for job_driver.drain, - * which will in turn call this callback after doing generic block job - * stuff. - */ - void (*drain)(BlockJob *job); }; /** diff --git a/block/backup.c b/block/backup.c index 715e1d3be8..7930004bbd 100644 --- a/block/backup.c +++ b/block/backup.c @@ -320,21 +320,6 @@ void backup_do_checkpoint(BlockJob *job, Error **errp) hbitmap_set(backup_job->copy_bitmap, 0, backup_job->len); } -static void backup_drain(BlockJob *job) -{ - BackupBlockJob *s = container_of(job, BackupBlockJob, common); - - /* Need to keep a reference in case blk_drain triggers execution - * of backup_complete... - */ - if (s->target) { - BlockBackend *target = s->target; - blk_ref(target); - blk_drain(target); - blk_unref(target); - } -} - static BlockErrorAction backup_error_action(BackupBlockJob *job, bool read, int error) { @@ -493,8 +478,7 @@ static const BlockJobDriver backup_job_driver = { .commit = backup_commit, .abort = backup_abort, .clean = backup_clean, - }, - .drain = backup_drain, + } }; static int64_t backup_calculate_cluster_size(BlockDriverState *target, diff --git a/block/mirror.c b/block/mirror.c index 8cb75fb409..8456ccd89d 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -644,14 +644,11 @@ static int mirror_exit_common(Job *job) bdrv_ref(mirror_top_bs); bdrv_ref(target_bs); - /* Remove target parent that still uses BLK_PERM_WRITE/RESIZE before + /* + * Remove target parent that still uses BLK_PERM_WRITE/RESIZE before * inserting target_bs at s->to_replace, where we might not be able to get * these permissions. - * - * Note that blk_unref() alone doesn't necessarily drop permissions because - * we might be running nested inside mirror_drain(), which takes an extra - * reference, so use an explicit blk_set_perm() first. */ - blk_set_perm(s->target, 0, BLK_PERM_ALL, &error_abort); + */ blk_unref(s->target); s->target = NULL; @@ -1143,21 +1140,6 @@ static bool mirror_drained_poll(BlockJob *job) return !!s->in_flight; } -static void mirror_drain(BlockJob *job) -{ - MirrorBlockJob *s = container_of(job, MirrorBlockJob, common); - - /* Need to keep a reference in case blk_drain triggers execution - * of mirror_complete... - */ - if (s->target) { - BlockBackend *target = s->target; - blk_ref(target); - blk_drain(target); - blk_unref(target); - } -} - static const BlockJobDriver mirror_job_driver = { .job_driver = { .instance_size = sizeof(MirrorBlockJob), @@ -1172,7 +1154,6 @@ static const BlockJobDriver mirror_job_driver = { .complete = mirror_complete, }, .drained_poll = mirror_drained_poll, - .drain = mirror_drain, }; static const BlockJobDriver commit_active_job_driver = { @@ -1189,7 +1170,6 @@ static const BlockJobDriver commit_active_job_driver = { .complete = mirror_complete, }, .drained_poll = mirror_drained_poll, - .drain = mirror_drain, }; static void coroutine_fn diff --git a/blockjob.c b/blockjob.c index 20b7f557da..f64ee3197b 100644 --- a/blockjob.c +++ b/blockjob.c @@ -92,13 +92,25 @@ void block_job_free(Job *job) void block_job_drain(Job *job) { BlockJob *bjob = container_of(job, BlockJob, job); - const JobDriver *drv = job->driver; - BlockJobDriver *bjdrv = container_of(drv, BlockJobDriver, job_driver); + GSList *nodes = NULL, *el; - blk_drain(bjob->blk); - if (bjdrv->drain) { - bjdrv->drain(bjob); + for (el = bjob->nodes; el; el = el->next) { + BdrvChild *c = el->data; + bdrv_ref(c->bs); + nodes = g_slist_prepend(nodes, c->bs); + } + + for (el = nodes; el; el = el->next) { + BlockDriverState *bs = el->data; + bdrv_drained_begin(bs); } + for (el = nodes; el; el = el->next) { + BlockDriverState *bs = el->data; + bdrv_drained_end(bs); + bdrv_unref(bs); + } + + g_slist_free(nodes); } static char *child_job_get_parent_desc(BdrvChild *c) -- 2.18.0