qmp: add 'busy' member to BlockJobInfo

Because pausing a job is asynchronous, we need to know whether it has
completed.  This is described by the "busy" field of BlockJob; copy it
to BlockJobInfo.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

blockjob.c

@@ -168,6 +168,7 @@ BlockJobInfo *block_job_query(BlockJob *job)
     info->type   = g_strdup(job->job_type->job_type);
     info->device = g_strdup(bdrv_get_device_name(job->bs));
     info->len    = job->len;
+    info->busy   = job->busy;
     info->offset = job->offset;
     info->speed  = job->speed;
     return info;

qapi-schema.json

@@ -1098,6 +1098,9 @@
 #
 # @len: the maximum progress value
 #
+# @busy: false if the job is known to be in a quiescent state, with
+#        no pending I/O.  Since 1.3.
+#
 # @offset: the current progress value
 #
 # @speed: the rate limit, bytes per second
@@ -1106,7 +1109,7 @@
 ##
 { 'type': 'BlockJobInfo',
   'data': {'type': 'str', 'device': 'str', 'len': 'int',
-           'offset': 'int', 'speed': 'int'} }
+           'offset': 'int', 'busy': 'bool', 'speed': 'int'} }
 
 ##
 # @query-block-jobs: