Merge remote-tracking branch 'remotes/xanclic/tags/pull-block-2018-08-31-v2' into...

Block patches:
- (Block) job exit refactoring, part 1
  (removing job_defer_to_main_loop())
- test-bdrv-drain leak fix

# gpg: Signature made Fri 31 Aug 2018 15:30:33 BST
# gpg:                using RSA key F407DB0061D5CF40
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>"
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/xanclic/tags/pull-block-2018-08-31-v2:
  jobs: remove job_defer_to_main_loop
  jobs: remove ret argument to job_completed; privatize it
  block/backup: make function variables consistently named
  jobs: utilize job_exit shim
  block/mirror: utilize job_exit shim
  block/commit: utilize job_exit shim
  jobs: add exit shim
  jobs: canonize Error object
  jobs: change start callback to run callback
  tests: fix bdrv-drain leak

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --combined job.c
index b9ebd1c091436521ea4c1ce255ba28bfba597f16,b960e727100b95323f9847140d167d1e2cc648fb..2327d790cc81744568bb2ac40732eee55951485e
--- 1/job.c
--- 2/job.c
+++ b/job.c
@@@ -174,7 -174,7 +174,7 @@@ static void job_state_transition(Job *j
      job->status = s1;
  
      if (!job_is_internal(job) && s1 != s0) {
 -        qapi_event_send_job_status_change(job->id, job->status, &error_abort);
 +        qapi_event_send_job_status_change(job->id, job->status);
      }
  }
  
@@@ -369,7 -369,7 +369,7 @@@ void job_unref(Job *job
  
          QLIST_REMOVE(job, job_list);
  
-         g_free(job->error);
+         error_free(job->err);
          g_free(job->id);
          g_free(job);
      }
@@@ -535,6 -535,20 +535,20 @@@ void job_drain(Job *job
      }
  }
  
+ static void job_completed(Job *job);
+ 
+ static void job_exit(void *opaque)
+ {
+     Job *job = (Job *)opaque;
+     AioContext *aio_context = job->aio_context;
+ 
+     if (job->driver->exit) {
+         aio_context_acquire(aio_context);
+         job->driver->exit(job);
+         aio_context_release(aio_context);
+     }
+     job_completed(job);
+ }
  
  /**
   * All jobs must allow a pause point before entering their job proper. This
@@@ -544,16 -558,18 +558,18 @@@ static void coroutine_fn job_co_entry(v
  {
      Job *job = opaque;
  
-     assert(job && job->driver && job->driver->start);
+     assert(job && job->driver && job->driver->run);
      job_pause_point(job);
-     job->driver->start(job);
+     job->ret = job->driver->run(job, &job->err);
+     job->deferred_to_main_loop = true;
+     aio_bh_schedule_oneshot(qemu_get_aio_context(), job_exit, job);
  }
  
  
  void job_start(Job *job)
  {
      assert(job && !job_started(job) && job->paused &&
-            job->driver && job->driver->start);
+            job->driver && job->driver->run);
      job->co = qemu_coroutine_create(job_co_entry, job);
      job->pause_count--;
      job->busy = true;
@@@ -666,8 -682,8 +682,8 @@@ static void job_update_rc(Job *job
          job->ret = -ECANCELED;
      }
      if (job->ret) {
-         if (!job->error) {
-             job->error = g_strdup(strerror(-job->ret));
+         if (!job->err) {
+             error_setg(&job->err, "%s", strerror(-job->ret));
          }
          job_state_transition(job, JOB_STATUS_ABORTING);
      }
@@@ -865,19 -881,12 +881,12 @@@ static void job_completed_txn_success(J
      }
  }
  
- void job_completed(Job *job, int ret, Error *error)
+ static void job_completed(Job *job)
  {
      assert(job && job->txn && !job_is_completed(job));
  
-     job->ret = ret;
-     if (error) {
-         assert(job->ret < 0);
-         job->error = g_strdup(error_get_pretty(error));
-         error_free(error);
-     }
- 
      job_update_rc(job);
-     trace_job_completed(job, ret, job->ret);
+     trace_job_completed(job, job->ret);
      if (job->ret) {
          job_completed_txn_abort(job);
      } else {
@@@ -893,7 -902,7 +902,7 @@@ void job_cancel(Job *job, bool force
      }
      job_cancel_async(job, force);
      if (!job_started(job)) {
-         job_completed(job, -ECANCELED, NULL);
+         job_completed(job);
      } else if (job->deferred_to_main_loop) {
          job_completed_txn_abort(job);
      } else {
@@@ -956,38 -965,6 +965,6 @@@ void job_complete(Job *job, Error **err
      job->driver->complete(job, errp);
  }
  
- 
- typedef struct {
-     Job *job;
-     JobDeferToMainLoopFn *fn;
-     void *opaque;
- } JobDeferToMainLoopData;
- 
- static void job_defer_to_main_loop_bh(void *opaque)
- {
-     JobDeferToMainLoopData *data = opaque;
-     Job *job = data->job;
-     AioContext *aio_context = job->aio_context;
- 
-     aio_context_acquire(aio_context);
-     data->fn(data->job, data->opaque);
-     aio_context_release(aio_context);
- 
-     g_free(data);
- }
- 
- void job_defer_to_main_loop(Job *job, JobDeferToMainLoopFn *fn, void *opaque)
- {
-     JobDeferToMainLoopData *data = g_malloc(sizeof(*data));
-     data->job = job;
-     data->fn = fn;
-     data->opaque = opaque;
-     job->deferred_to_main_loop = true;
- 
-     aio_bh_schedule_oneshot(qemu_get_aio_context(),
-                             job_defer_to_main_loop_bh, data);
- }
- 
  int job_finish_sync(Job *job, void (*finish)(Job *, Error **errp), Error **errp)
  {
      Error *local_err = NULL;