[Qemu-block] [RFC PATCH 16/33] job: Move defer_to_main_loop to Job

[Kevin Wolf]

Signed-off-by: Kevin Wolf <address@hidden>
---
 include/block/blockjob.h     |  5 ----
 include/block/blockjob_int.h | 19 ---------------
 include/qemu/job.h           | 20 ++++++++++++++++
 block/backup.c               |  7 +++---
 block/commit.c               | 11 +++++----
 block/mirror.c               | 15 ++++++------
 block/stream.c               | 14 +++++------
 blockjob.c                   | 57 ++++----------------------------------------
 job.c                        | 33 +++++++++++++++++++++++++
 tests/test-bdrv-drain.c      |  7 +++---
 tests/test-blockjob-txn.c    | 13 +++++-----
 tests/test-blockjob.c        |  7 +++---
 12 files changed, 98 insertions(+), 110 deletions(-)

diff --git a/include/block/blockjob.h b/include/block/blockjob.h
index 04efc94ffc..90942826f5 100644
--- a/include/block/blockjob.h
+++ b/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;
 
diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
index e9790e9a0d..b0338282c8 100644
--- a/include/block/blockjob_int.h
+++ b/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
diff --git a/include/qemu/job.h b/include/qemu/job.h
index c1882bb0dd..63a40b2714 100644
--- a/include/qemu/job.h
+++ b/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;
@@ -124,6 +127,23 @@ Job *job_next(Job *job);
  */
 Job *job_get(const char *id);
 
+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);
 int job_apply_verb(Job *job, JobVerb bv, Error **errp);
diff --git a/block/backup.c b/block/backup.c
index 1d330b7266..ce9cc01617 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -317,11 +317,12 @@ typedef struct {
     int ret;
 } BackupCompleteData;
 
-static void backup_complete(BlockJob *job, void *opaque)
+static void backup_complete(Job *job, void *opaque)
 {
+    BlockJob *bjob = container_of(job, BlockJob, job);
     BackupCompleteData *data = opaque;
 
-    block_job_completed(job, data->ret);
+    block_job_completed(bjob, data->ret);
     g_free(data);
 }
 
@@ -519,7 +520,7 @@ static void coroutine_fn backup_run(void *opaque)
 
     data = g_malloc(sizeof(*data));
     data->ret = ret;
-    block_job_defer_to_main_loop(&job->common, backup_complete, data);
+    job_defer_to_main_loop(&job->common.job, backup_complete, data);
 }
 
 static const BlockJobDriver backup_job_driver = {
diff --git a/block/commit.c b/block/commit.c
index 85baea8f92..d326766e4d 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -72,9 +72,10 @@ typedef struct {
     int ret;
 } CommitCompleteData;
 
-static void commit_complete(BlockJob *job, void *opaque)
+static void commit_complete(Job *job, void *opaque)
 {
-    CommitBlockJob *s = container_of(job, CommitBlockJob, common);
+    CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
+    BlockJob *bjob = &s->common;
     CommitCompleteData *data = opaque;
     BlockDriverState *top = blk_bs(s->top);
     BlockDriverState *base = blk_bs(s->base);
@@ -90,7 +91,7 @@ static void commit_complete(BlockJob *job, void *opaque)
      * the normal backing chain can be restored. */
     blk_unref(s->base);
 
-    if (!job_is_cancelled(&s->common.job) && ret == 0) {
+    if (!job_is_cancelled(job) && ret == 0) {
         /* success */
         ret = bdrv_drop_intermediate(s->commit_top_bs, base,
                                      s->backing_file_str);
@@ -114,7 +115,7 @@ static void commit_complete(BlockJob *job, void *opaque)
      * block_job_finish_sync()), block_job_completed() won't free it and
      * therefore the blockers on the intermediate nodes remain. This would
      * cause bdrv_set_backing_hd() to fail. */
-    block_job_remove_all_bdrv(job);
+    block_job_remove_all_bdrv(bjob);
 
     block_job_completed(&s->common, ret);
     g_free(data);
@@ -211,7 +212,7 @@ out:
 
     data = g_malloc(sizeof(*data));
     data->ret = ret;
-    block_job_defer_to_main_loop(&s->common, commit_complete, data);
+    job_defer_to_main_loop(&s->common.job, commit_complete, data);
 }
 
 static const BlockJobDriver commit_job_driver = {
diff --git a/block/mirror.c b/block/mirror.c
index 937b915268..cb6a4f6fe1 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -484,9 +484,10 @@ typedef struct {
     int ret;
 } MirrorExitData;
 
-static void mirror_exit(BlockJob *job, void *opaque)
+static void mirror_exit(Job *job, void *opaque)
 {
-    MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
+    MirrorBlockJob *s = container_of(job, MirrorBlockJob, common.job);
+    BlockJob *bjob = &s->common;
     MirrorExitData *data = opaque;
     AioContext *replace_aio_context = NULL;
     BlockDriverState *src = s->source;
@@ -568,7 +569,7 @@ static void mirror_exit(BlockJob *job, void *opaque)
      * the blockers on the intermediate nodes so that the resulting state is
      * valid. Also give up permissions on mirror_top_bs->backing, which might
      * block the removal. */
-    block_job_remove_all_bdrv(job);
+    block_job_remove_all_bdrv(bjob);
     bdrv_child_try_set_perm(mirror_top_bs->backing, 0, BLK_PERM_ALL,
                             &error_abort);
     bdrv_replace_node(mirror_top_bs, backing_bs(mirror_top_bs), &error_abort);
@@ -576,9 +577,9 @@ static void mirror_exit(BlockJob *job, void *opaque)
     /* We just changed the BDS the job BB refers to (with either or both of the
      * bdrv_replace_node() calls), so switch the BB back so the cleanup does
      * the right thing. We don't need any permissions any more now. */
-    blk_remove_bs(job->blk);
-    blk_set_perm(job->blk, 0, BLK_PERM_ALL, &error_abort);
-    blk_insert_bs(job->blk, mirror_top_bs, &error_abort);
+    blk_remove_bs(bjob->blk);
+    blk_set_perm(bjob->blk, 0, BLK_PERM_ALL, &error_abort);
+    blk_insert_bs(bjob->blk, mirror_top_bs, &error_abort);
 
     block_job_completed(&s->common, data->ret);
 
@@ -897,7 +898,7 @@ immediate_exit:
     if (need_drain) {
         bdrv_drained_begin(bs);
     }
-    block_job_defer_to_main_loop(&s->common, mirror_exit, data);
+    job_defer_to_main_loop(&s->common.job, mirror_exit, data);
 }
 
 static void mirror_complete(BlockJob *job, Error **errp)
diff --git a/block/stream.c b/block/stream.c
index 22c71ae100..0bba81678c 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -58,16 +58,16 @@ typedef struct {
     int ret;
 } StreamCompleteData;
 
-static void stream_complete(BlockJob *job, void *opaque)
+static void stream_complete(Job *job, void *opaque)
 {
-    StreamBlockJob *s = container_of(job, StreamBlockJob, common);
+    StreamBlockJob *s = container_of(job, StreamBlockJob, common.job);
+    BlockJob *bjob = &s->common;
     StreamCompleteData *data = opaque;
-    BlockDriverState *bs = blk_bs(job->blk);
+    BlockDriverState *bs = blk_bs(bjob->blk);
     BlockDriverState *base = s->base;
     Error *local_err = NULL;
 
-    if (!job_is_cancelled(&s->common.job) && bs->backing &&
-        data->ret == 0) {
+    if (!job_is_cancelled(job) && bs->backing && data->ret == 0) {
         const char *base_id = NULL, *base_fmt = NULL;
         if (base) {
             base_id = s->backing_file_str;
@@ -88,7 +88,7 @@ out:
     /* Reopen the image back in read-only mode if necessary */
     if (s->bs_flags != bdrv_get_flags(bs)) {
         /* Give up write permissions before making it read-only */
-        blk_set_perm(job->blk, 0, BLK_PERM_ALL, &error_abort);
+        blk_set_perm(bjob->blk, 0, BLK_PERM_ALL, &error_abort);
         bdrv_reopen(bs, s->bs_flags, NULL);
     }
 
@@ -205,7 +205,7 @@ out:
     /* Modify backing chain and close BDSes in main loop */
     data = g_malloc(sizeof(*data));
     data->ret = ret;
-    block_job_defer_to_main_loop(&s->common, stream_complete, data);
+    job_defer_to_main_loop(&s->common.job, stream_complete, data);
 }
 
 static const BlockJobDriver stream_job_driver = {
diff --git a/blockjob.c b/blockjob.c
index 734dd168dd..7524058e45 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -347,7 +347,7 @@ static void block_job_decommission(BlockJob *job)
     job->completed = true;
     job->busy = false;
     job->paused = false;
-    job->deferred_to_main_loop = true;
+    job->job.deferred_to_main_loop = true;
     block_job_txn_del_job(job);
     job_state_transition(&job->job, JOB_STATUS_NULL);
     job_unref(&job->job);
@@ -502,7 +502,7 @@ static int block_job_finish_sync(BlockJob *job,
     /* block_job_drain calls block_job_enter, and it should be enough to
      * induce progress until the job completes or moves to the main thread.
     */
-    while (!job->deferred_to_main_loop && !job->completed) {
+    while (!job->job.deferred_to_main_loop && !job->completed) {
         block_job_drain(job);
     }
     while (!job->completed) {
@@ -722,7 +722,7 @@ void block_job_cancel(BlockJob *job, bool force)
     block_job_cancel_async(job, force);
     if (!block_job_started(job)) {
         block_job_completed(job, -ECANCELED);
-    } else if (job->deferred_to_main_loop) {
+    } else if (job->job.deferred_to_main_loop) {
         block_job_completed_txn_abort(job);
     } else {
         block_job_enter(job);
@@ -1036,7 +1036,7 @@ static void block_job_enter_cond(BlockJob *job, 
bool(*fn)(BlockJob *job))
     if (!block_job_started(job)) {
         return;
     }
-    if (job->deferred_to_main_loop) {
+    if (job->job.deferred_to_main_loop) {
         return;
     }
 
@@ -1051,7 +1051,7 @@ static void block_job_enter_cond(BlockJob *job, 
bool(*fn)(BlockJob *job))
         return;
     }
 
-    assert(!job->deferred_to_main_loop);
+    assert(!job->job.deferred_to_main_loop);
     timer_del(&job->sleep_timer);
     job->busy = true;
     block_job_unlock();
@@ -1157,50 +1157,3 @@ BlockErrorAction block_job_error_action(BlockJob *job, 
BlockdevOnError on_err,
     }
     return action;
 }
-
-typedef struct {
-    BlockJob *job;
-    AioContext *aio_context;
-    BlockJobDeferToMainLoopFn *fn;
-    void *opaque;
-} BlockJobDeferToMainLoopData;
-
-static void block_job_defer_to_main_loop_bh(void *opaque)
-{
-    BlockJobDeferToMainLoopData *data = opaque;
-    AioContext *aio_context;
-
-    /* Prevent race with block_job_defer_to_main_loop() */
-    aio_context_acquire(data->aio_context);
-
-    /* Fetch BDS AioContext again, in case it has changed */
-    aio_context = blk_get_aio_context(data->job->blk);
-    if (aio_context != data->aio_context) {
-        aio_context_acquire(aio_context);
-    }
-
-    data->fn(data->job, data->opaque);
-
-    if (aio_context != data->aio_context) {
-        aio_context_release(aio_context);
-    }
-
-    aio_context_release(data->aio_context);
-
-    g_free(data);
-}
-
-void block_job_defer_to_main_loop(BlockJob *job,
-                                  BlockJobDeferToMainLoopFn *fn,
-                                  void *opaque)
-{
-    BlockJobDeferToMainLoopData *data = g_malloc(sizeof(*data));
-    data->job = job;
-    data->aio_context = blk_get_aio_context(job->blk);
-    data->fn = fn;
-    data->opaque = opaque;
-    job->deferred_to_main_loop = true;
-
-    aio_bh_schedule_oneshot(qemu_get_aio_context(),
-                            block_job_defer_to_main_loop_bh, data);
-}
diff --git a/job.c b/job.c
index a28a7765e5..8e79bcfb74 100644
--- a/job.c
+++ b/job.c
@@ -28,6 +28,7 @@
 #include "qapi/error.h"
 #include "qemu/job.h"
 #include "qemu/id.h"
+#include "qemu/main-loop.h"
 #include "trace-root.h"
 
 static QLIST_HEAD(, Job) jobs = QLIST_HEAD_INITIALIZER(jobs);
@@ -171,3 +172,35 @@ void job_unref(Job *job)
         g_free(job);
     }
 }
+
+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;
+
+    /* Prevent race with job_defer_to_main_loop() */
+    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);
+}
diff --git a/tests/test-bdrv-drain.c b/tests/test-bdrv-drain.c
index f9e37d479c..4f8cba8377 100644
--- a/tests/test-bdrv-drain.c
+++ b/tests/test-bdrv-drain.c
@@ -496,9 +496,10 @@ typedef struct TestBlockJob {
     bool should_complete;
 } TestBlockJob;
 
-static void test_job_completed(BlockJob *job, void *opaque)
+static void test_job_completed(Job *job, void *opaque)
 {
-    block_job_completed(job, 0);
+    BlockJob *bjob = container_of(job, BlockJob, job);
+    block_job_completed(bjob, 0);
 }
 
 static void coroutine_fn test_job_start(void *opaque)
@@ -510,7 +511,7 @@ static void coroutine_fn test_job_start(void *opaque)
         block_job_sleep_ns(&s->common, 100000);
     }
 
-    block_job_defer_to_main_loop(&s->common, test_job_completed, NULL);
+    job_defer_to_main_loop(&s->common.job, test_job_completed, NULL);
 }
 
 static void test_job_complete(BlockJob *job, Error **errp)
diff --git a/tests/test-blockjob-txn.c b/tests/test-blockjob-txn.c
index 26b4bbb230..c03f9662d8 100644
--- a/tests/test-blockjob-txn.c
+++ b/tests/test-blockjob-txn.c
@@ -24,16 +24,17 @@ typedef struct {
     int *result;
 } TestBlockJob;
 
-static void test_block_job_complete(BlockJob *job, void *opaque)
+static void test_block_job_complete(Job *job, void *opaque)
 {
-    BlockDriverState *bs = blk_bs(job->blk);
+    BlockJob *bjob = container_of(job, BlockJob, job);
+    BlockDriverState *bs = blk_bs(bjob->blk);
     int rc = (intptr_t)opaque;
 
-    if (job_is_cancelled(&job->job)) {
+    if (job_is_cancelled(job)) {
         rc = -ECANCELED;
     }
 
-    block_job_completed(job, rc);
+    block_job_completed(bjob, rc);
     bdrv_unref(bs);
 }
 
@@ -54,8 +55,8 @@ static void coroutine_fn test_block_job_run(void *opaque)
         }
     }
 
-    block_job_defer_to_main_loop(job, test_block_job_complete,
-                                 (void *)(intptr_t)s->rc);
+    job_defer_to_main_loop(&job->job, test_block_job_complete,
+                           (void *)(intptr_t)s->rc);
 }
 
 typedef struct {
diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c
index fa31481537..5f43bd72a4 100644
--- a/tests/test-blockjob.c
+++ b/tests/test-blockjob.c
@@ -161,11 +161,12 @@ typedef struct CancelJob {
     bool completed;
 } CancelJob;
 
-static void cancel_job_completed(BlockJob *job, void *opaque)
+static void cancel_job_completed(Job *job, void *opaque)
 {
+    BlockJob *bjob = container_of(job, BlockJob, job);
     CancelJob *s = opaque;
     s->completed = true;
-    block_job_completed(job, 0);
+    block_job_completed(bjob, 0);
 }
 
 static void cancel_job_complete(BlockJob *job, Error **errp)
@@ -191,7 +192,7 @@ static void coroutine_fn cancel_job_start(void *opaque)
     }
 
  defer:
-    block_job_defer_to_main_loop(&s->common, cancel_job_completed, s);
+    job_defer_to_main_loop(&s->common.job, cancel_job_completed, s);
 }
 
 static const BlockJobDriver test_cancel_driver = {
-- 
2.13.6