The backup block job directly accesses the driver field in BlockJob. Add
a wrapper for getting it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 include/block/blockjob.h | 7 +++++++
 block/backup.c           | 8 +++++---
 blockjob.c               | 5 +++++
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/include/block/blockjob.h b/include/block/blockjob.h
index 5aa8a6aaec..0b57d53084 100644
--- a/include/block/blockjob.h
+++ b/include/block/blockjob.h
@@ -452,4 +452,11 @@ void block_job_txn_add_job(BlockJobTxn *txn, BlockJob *job);
  */
 bool block_job_is_internal(BlockJob *job);
 
+/**
+ * block_job_driver:
+ *
+ * Returns the driver associated with a block job.
+ */
+const BlockJobDriver *block_job_driver(BlockJob *job);
+
 #endif
diff --git a/block/backup.c b/block/backup.c
index cfdb6ecdf5..e14d99560d 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -47,6 +47,8 @@ typedef struct BackupBlockJob {
     HBitmap *copy_bitmap;
 } BackupBlockJob;
 
+static const BlockJobDriver backup_job_driver;
+
 /* See if in-flight requests overlap and wait for them to complete */
 static void coroutine_fn wait_for_overlapping_requests(BackupBlockJob *job,
                                                        int64_t start,
@@ -241,7 +243,7 @@ void backup_do_checkpoint(BlockJob *job, Error **errp)
     BackupBlockJob *backup_job = container_of(job, BackupBlockJob, common);
     int64_t len;
 
-    assert(job->driver->job_type == BLOCK_JOB_TYPE_BACKUP);
+    assert(block_job_driver(job) == &backup_job_driver);
 
     if (backup_job->sync_mode != MIRROR_SYNC_MODE_NONE) {
         error_setg(errp, "The backup job only supports block checkpoint in"
@@ -259,7 +261,7 @@ void backup_wait_for_overlapping_requests(BlockJob *job, int64_t offset,
     BackupBlockJob *backup_job = container_of(job, BackupBlockJob, common);
     int64_t start, end;
 
-    assert(job->driver->job_type == BLOCK_JOB_TYPE_BACKUP);
+    assert(block_job_driver(job) == &backup_job_driver);
 
     start = QEMU_ALIGN_DOWN(offset, backup_job->cluster_size);
     end = QEMU_ALIGN_UP(offset + bytes, backup_job->cluster_size);
@@ -272,7 +274,7 @@ void backup_cow_request_begin(CowRequest *req, BlockJob *job,
     BackupBlockJob *backup_job = container_of(job, BackupBlockJob, common);
     int64_t start, end;
 
-    assert(job->driver->job_type == BLOCK_JOB_TYPE_BACKUP);
+    assert(block_job_driver(job) == &backup_job_driver);
 
     start = QEMU_ALIGN_DOWN(offset, backup_job->cluster_size);
     end = QEMU_ALIGN_UP(offset + bytes, backup_job->cluster_size);
diff --git a/blockjob.c b/blockjob.c
index b6e27c7f80..985621e256 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -359,6 +359,11 @@ static bool block_job_started(BlockJob *job)
     return job->co;
 }
 
+const BlockJobDriver *block_job_driver(BlockJob *job)
+{
+    return job->driver;
+}
+
 /**
  * All jobs must allow a pause point before entering their job proper. This
  * ensures that jobs can be paused prior to being started, then resumed later.
-- 
2.13.6

On 2018-05-09 18:26, Kevin Wolf wrote:
> The backup block job directly accesses the driver field in BlockJob. Add
> a wrapper for getting it.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> ---
>  include/block/blockjob.h | 7 +++++++
>  block/backup.c           | 8 +++++---
>  blockjob.c               | 5 +++++
>  3 files changed, 17 insertions(+), 3 deletions(-)

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

On 05/09/2018 12:26 PM, Kevin Wolf wrote:
> The backup block job directly accesses the driver field in BlockJob. Add
> a wrapper for getting it.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> Reviewed-by: Eric Blake <eblake@redhat.com>

I'm not too far into this series yet but I suppose it turns out that
it's more useful to get the driver than to ask the job system what the
job type is.

Probably there's some QAPI reasons for why that's true, too...

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