From a0b03467a363f0e6804042925ea1df8ef56f8a46 Mon Sep 17 00:00:00 2001

From: John Snow <jsnow@redhat.com>

Date: Mon, 10 Sep 2018 18:17:42 +0200

Subject: [PATCH 04/25] block/commit: utilize job_exit shim

RH-Author: John Snow <jsnow@redhat.com>

Message-id: <20180910181803.11781-5-jsnow@redhat.com>

Patchwork-id: 82110

O-Subject: [RHEL-7.6 qemu-kvm-rhev PATCH 04/25] block/commit: utilize job_exit shim

Bugzilla: 1626061

RH-Acked-by: Max Reitz <mreitz@redhat.com>

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

RH-Acked-by: Kevin Wolf <kwolf@redhat.com>

Change the manual deferment to commit_complete into the implicit

callback to job_exit, renaming commit_complete to commit_exit.

This conversion does change the timing of when job_completed is

called to after the bdrv_replace_node and bdrv_unref calls, which

could have implications for bjob->blk which will now be put down

after this cleanup.

Kevin highlights that we did not take any permissions for that backend

at job creation time, so it is safe to reorder these operations.

Signed-off-by: John Snow <jsnow@redhat.com>

Reviewed-by: Max Reitz <mreitz@redhat.com>

Message-id: 20180830015734.19765-5-jsnow@redhat.com

Reviewed-by: Jeff Cody <jcody@redhat.com>

Signed-off-by: Max Reitz <mreitz@redhat.com>

(cherry picked from commit f369b48dc4095861223f9bc4329935599e03b1c5)

Signed-off-by: John Snow <jsnow@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 block/commit.c | 22 +++++-----------------

 1 file changed, 5 insertions(+), 17 deletions(-)

diff --git a/block/commit.c b/block/commit.c

index af7579d..25b3cb8 100644

--- a/block/commit.c

+++ b/block/commit.c

@@ -68,19 +68,13 @@ static int coroutine_fn commit_populate(BlockBackend *bs, BlockBackend *base,

     return 0;

 }

-typedef struct {

-    int ret;

-} CommitCompleteData;

-

-static void commit_complete(Job *job, void *opaque)

+static void commit_exit(Job *job)

 {

     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);

     BlockDriverState *commit_top_bs = s->commit_top_bs;

-    int ret = data->ret;

     bool remove_commit_top_bs = false;

     /* Make sure commit_top_bs and top stay around until bdrv_replace_node() */

@@ -91,10 +85,10 @@ static void commit_complete(Job *job, void *opaque)

      * the normal backing chain can be restored. */

     blk_unref(s->base);

-    if (!job_is_cancelled(job) && ret == 0) {

+    if (!job_is_cancelled(job) && job->ret == 0) {

         /* success */

-        ret = bdrv_drop_intermediate(s->commit_top_bs, base,

-                                     s->backing_file_str);

+        job->ret = bdrv_drop_intermediate(s->commit_top_bs, base,

+                                          s->backing_file_str);

     } else {

         /* XXX Can (or should) we somehow keep 'consistent read' blocked even

          * after the failed/cancelled commit job is gone? If we already wrote

@@ -117,9 +111,6 @@ static void commit_complete(Job *job, void *opaque)

      * bdrv_set_backing_hd() to fail. */

     block_job_remove_all_bdrv(bjob);

-    job_completed(job, ret);

-    g_free(data);

-

     /* If bdrv_drop_intermediate() didn't already do that, remove the commit

      * filter driver from the backing chain. Do this as the final step so that

      * the 'consistent read' permission can be granted.  */

@@ -137,7 +128,6 @@ static void commit_complete(Job *job, void *opaque)

 static int coroutine_fn commit_run(Job *job, Error **errp)

 {

     CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);

-    CommitCompleteData *data;

     int64_t offset;

     uint64_t delay_ns = 0;

     int ret = 0;

@@ -210,9 +200,6 @@ static int coroutine_fn commit_run(Job *job, Error **errp)

 out:

     qemu_vfree(buf);

-    data = g_malloc(sizeof(*data));

-    data->ret = ret;

-    job_defer_to_main_loop(&s->common.job, commit_complete, data);

     return ret;

 }

@@ -224,6 +211,7 @@ static const BlockJobDriver commit_job_driver = {

         .user_resume   = block_job_user_resume,

         .drain         = block_job_drain,

         .run           = commit_run,

+        .exit          = commit_exit,

     },

 };

-- 

1.8.3.1