block: use Error mechanism instead of -errno for block_job_create()

The block job API uses -errno return values internally and we convert
these to Error in the QMP functions.  This is ugly because the Error
should be created at the point where we still have all the relevant
information.  More importantly, it is hard to add new error cases to
this case since we quickly run out of -errno values without losing
information.

Go ahead and use Error directly and don't convert later.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

1 files changed, 5 insertions, 6 deletions

diff --git a/block/stream.c b/block/stream.c
index 0efe1ad..7002dc8 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -280,16 +280,16 @@ static BlockJobType stream_job_type = {
     .set_speed     = stream_set_speed,
 };
 
-int stream_start(BlockDriverState *bs, BlockDriverState *base,
-                 const char *base_id, BlockDriverCompletionFunc *cb,
-                 void *opaque)
+void stream_start(BlockDriverState *bs, BlockDriverState *base,
+                  const char *base_id, BlockDriverCompletionFunc *cb,
+                  void *opaque, Error **errp)
 {
     StreamBlockJob *s;
     Coroutine *co;
 
-    s = block_job_create(&stream_job_type, bs, cb, opaque);
+    s = block_job_create(&stream_job_type, bs, cb, opaque, errp);
     if (!s) {
-        return -EBUSY; /* bs must already be in use */
+        return;
     }
 
     s->base = base;
@@ -300,5 +300,4 @@ int stream_start(BlockDriverState *bs, BlockDriverState *base,
     co = qemu_coroutine_create(stream_run);
     trace_stream_start(bs, base, s, co, opaque);
     qemu_coroutine_enter(co, s);
-    return 0;
 }