block: drop bs->job

Drop remaining users of bs->job:
1. assertions actually duplicated by assert(!bs->refcnt)
2. trace-point seems not enough reason to change stream_start to return
   BlockJob pointer
3. Restricting creation of two jobs based on same bs is bad idea, as
   3.1 Some jobs creates filters to be their main node, so, this check
   don't actually prevent creating second job on same real node (which
   will create another filter node) (but I hope it is restricted by
   other mechanisms)
   3.2 Even without bs->job we have two systems of permissions:
   op-blockers and BLK_PERM
   3.3 We may want to run several jobs on one node one day

And finally, drop bs->job pointer itself. Hurrah!

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 0 insertions, 8 deletions

diff --git a/blockjob.c b/blockjob.c
index c3620ec544..458ae76f51 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -83,9 +83,7 @@ BlockJob *block_job_get(const char *id)
 void block_job_free(Job *job)
 {
     BlockJob *bjob = container_of(job, BlockJob, job);
-    BlockDriverState *bs = blk_bs(bjob->blk);
 
-    bs->job = NULL;
     block_job_remove_all_bdrv(bjob);
     blk_unref(bjob->blk);
     error_free(bjob->blocker);
@@ -402,11 +400,6 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,
     BlockJob *job;
     int ret;
 
-    if (bs->job) {
-        error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
-        return NULL;
-    }
-
     if (job_id == NULL && !(flags & JOB_INTERNAL)) {
         job_id = bdrv_get_device_name(bs);
     }
@@ -449,7 +442,6 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,
     error_setg(&job->blocker, "block device is in use by block job: %s",
                job_type_str(&job->job));
     block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort);
-    bs->job = job;
 
     bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);