blockjob: let ratelimit handle a speed of 0

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20210614081130.22134-4-eesposit@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

blockjob.c

@@ -300,10 +300,6 @@ bool block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
 
 int64_t block_job_ratelimit_get_delay(BlockJob *job, uint64_t n)
 {
-    if (!job->speed) {
-        return 0;
-    }
-
     return ratelimit_calculate_delay(&job->limit, n);
 }
 
@@ -472,12 +468,9 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver,
     blk_set_disable_request_queuing(blk, true);
     blk_set_allow_aio_context_change(blk, true);
 
-    /* Only set speed when necessary to avoid NotSupported error */
-    if (speed != 0) {
-        if (!block_job_set_speed(job, speed, errp)) {
-            job_early_fail(&job->job);
-            return NULL;
-        }
+    if (!block_job_set_speed(job, speed, errp)) {
+        job_early_fail(&job->job);
+        return NULL;
     }
 
     return job;