Merge remote-tracking branch 'remotes/xanclic/tags/pull-block-2018-09-25' into staging

Block layer patches:
- Drain fixes
- node-name parameters for block-commit
- Refactor block jobs to use transactional callbacks for exiting

# gpg: Signature made Tue 25 Sep 2018 16:12:44 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-2018-09-25: (42 commits)
  test-bdrv-drain: Test draining job source child and parent
  block: Use a single global AioWait
  test-bdrv-drain: Fix outdated comments
  test-bdrv-drain: AIO_WAIT_WHILE() in job .commit/.abort
  job: Avoid deadlocks in job_completed_txn_abort()
  test-bdrv-drain: Test nested poll in bdrv_drain_poll_top_level()
  block: Remove aio_poll() in bdrv_drain_poll variants
  blockjob: Lie better in child_job_drained_poll()
  block-backend: Decrease in_flight only after callback
  block-backend: Fix potential double blk_delete()
  block-backend: Add .drained_poll callback
  block: Add missing locking in bdrv_co_drain_bh_cb()
  test-bdrv-drain: Test AIO_WAIT_WHILE() in completion callback
  job: Use AIO_WAIT_WHILE() in job_finish_sync()
  test-blockjob: Acquire AioContext around job_cancel_sync()
  test-bdrv-drain: Drain with block jobs in an I/O thread
  aio-wait: Increase num_waiters even in home thread
  blockjob: Wake up BDS when job becomes idle
  job: Fix missing locking due to mismerge
  job: Fix nested aio_poll() hanging in job_txn_apply
  ...

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

3 files changed, 12 insertions, 6 deletions

diff --git a/util/aio-wait.c b/util/aio-wait.c
index b8a8f86dba..b4877493f8 100644
--- a/util/aio-wait.c
+++ b/util/aio-wait.c
@@ -26,21 +26,22 @@
 #include "qemu/main-loop.h"
 #include "block/aio-wait.h"
 
+AioWait global_aio_wait;
+
 static void dummy_bh_cb(void *opaque)
 {
     /* The point is to make AIO_WAIT_WHILE()'s aio_poll() return */
 }
 
-void aio_wait_kick(AioWait *wait)
+void aio_wait_kick(void)
 {
     /* The barrier (or an atomic op) is in the caller.  */
-    if (atomic_read(&wait->num_waiters)) {
+    if (atomic_read(&global_aio_wait.num_waiters)) {
         aio_bh_schedule_oneshot(qemu_get_aio_context(), dummy_bh_cb, NULL);
     }
 }
 
 typedef struct {
-    AioWait wait;
     bool done;
     QEMUBHFunc *cb;
     void *opaque;
@@ -54,7 +55,7 @@ static void aio_wait_bh(void *opaque)
     data->cb(data->opaque);
 
     data->done = true;
-    aio_wait_kick(&data->wait);
+    aio_wait_kick();
 }
 
 void aio_wait_bh_oneshot(AioContext *ctx, QEMUBHFunc *cb, void *opaque)
@@ -67,5 +68,5 @@ void aio_wait_bh_oneshot(AioContext *ctx, QEMUBHFunc *cb, void *opaque)
     assert(qemu_get_current_aio_context() == qemu_get_aio_context());
 
     aio_bh_schedule_oneshot(ctx, aio_wait_bh, &data);
-    AIO_WAIT_WHILE(&data.wait, ctx, !data.done);
+    AIO_WAIT_WHILE(ctx, !data.done);
 }
diff --git a/util/async.c b/util/async.c
index 05979f8014..c10642a385 100644
--- a/util/async.c
+++ b/util/async.c
@@ -400,7 +400,7 @@ static void co_schedule_bh_cb(void *opaque)
 
         /* Protected by write barrier in qemu_aio_coroutine_enter */
         atomic_set(&co->scheduled, NULL);
-        qemu_coroutine_enter(co);
+        qemu_aio_coroutine_enter(ctx, co);
         aio_context_release(ctx);
     }
 }
diff --git a/util/qemu-coroutine.c b/util/qemu-coroutine.c
index 1ba4191b84..2295928d33 100644
--- a/util/qemu-coroutine.c
+++ b/util/qemu-coroutine.c
@@ -198,3 +198,8 @@ bool qemu_coroutine_entered(Coroutine *co)
 {
     return co->caller;
 }
+
+AioContext *coroutine_fn qemu_coroutine_get_aio_context(Coroutine *co)
+{
+    return co->ctx;
+}