job: Move defer_to_main_loop to Job

Move the defer_to_main_loop functionality from BlockJob to Job.

The code can be simplified because we can use job->aio_context in
job_defer_to_main_loop_bh() now, instead of having to access the
BlockDriverState.

Probably taking the data->aio_context lock in addition was already
unnecessary in the old code because we didn't actually make use of
anything protected by the old AioContext except getting the new
AioContext, in case it changed between scheduling the BH and running it.
But it's certainly unnecessary now that the BDS isn't accessed at all
any more.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>

include/block/blockjob.h

@@ -92,11 +92,6 @@ typedef struct BlockJob {
      */
     bool ready;
 
-    /**
-     * Set to true when the job has deferred work to the main loop.
-     */
-    bool deferred_to_main_loop;
-
     /** Status that is published by the query-block-jobs QMP API */
     BlockDeviceIoStatus iostatus;
 

include/block/blockjob_int.h

@@ -233,23 +233,4 @@ void block_job_event_ready(BlockJob *job);
 BlockErrorAction block_job_error_action(BlockJob *job, BlockdevOnError on_err,
                                         int is_read, int error);
 
-typedef void BlockJobDeferToMainLoopFn(BlockJob *job, void *opaque);
-
-/**
- * block_job_defer_to_main_loop:
- * @job: The job
- * @fn: The function to run in the main loop
- * @opaque: The opaque value that is passed to @fn
- *
- * This function must be called by the main job coroutine just before it
- * returns.  @fn is executed in the main loop with the BlockDriverState
- * AioContext acquired.  Block jobs must call bdrv_unref(), bdrv_close(), and
- * anything that uses bdrv_drain_all() in the main loop.
- *
- * The @job AioContext is held while @fn executes.
- */
-void block_job_defer_to_main_loop(BlockJob *job,
-                                  BlockJobDeferToMainLoopFn *fn,
-                                  void *opaque);
-
 #endif

include/qemu/job.h

@@ -58,6 +58,9 @@ typedef struct Job {
      */
     bool cancelled;
 
+    /** Set to true when the job has deferred work to the main loop. */
+    bool deferred_to_main_loop;
+
     /** Element of the list of jobs */
     QLIST_ENTRY(Job) job_list;
 } Job;
@@ -131,6 +134,23 @@ Job *job_get(const char *id);
  */
 int job_apply_verb(Job *job, JobVerb verb, Error **errp);
 
+typedef void JobDeferToMainLoopFn(Job *job, void *opaque);
+
+/**
+ * @job: The job
+ * @fn: The function to run in the main loop
+ * @opaque: The opaque value that is passed to @fn
+ *
+ * This function must be called by the main job coroutine just before it
+ * returns.  @fn is executed in the main loop with the job AioContext acquired.
+ *
+ * Block jobs must call bdrv_unref(), bdrv_close(), and anything that uses
+ * bdrv_drain_all() in the main loop.
+ *
+ * The @job AioContext is held while @fn executes.
+ */
+void job_defer_to_main_loop(Job *job, JobDeferToMainLoopFn *fn, void *opaque);
+
 /* TODO To be removed from the public interface */
 void job_state_transition(Job *job, JobStatus s1);