diff options
| -rw-r--r-- | drivers/vhost/tcm_vhost.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c index afb530887936..96d3b47c82cd 100644 --- a/drivers/vhost/tcm_vhost.c +++ b/drivers/vhost/tcm_vhost.c @@ -83,9 +83,16 @@ struct vhost_scsi_inflight { struct vhost_scsi_virtqueue { struct vhost_virtqueue vq; - /* Track inflight reqs, protected by vq->mutex */ + /* + * Reference counting for inflight reqs, used for flush operation. At + * each time, one reference tracks new commands submitted, while we + * wait for another one to reach 0. + */ struct vhost_scsi_inflight inflights[2]; - /* Indicate current inflight in use, protected by vq->mutex */ + /* + * Indicate current inflight in use, protected by vq->mutex. + * Writers must also take dev mutex and flush under it. + */ int inflight_idx; }; @@ -1015,6 +1022,7 @@ static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index) vhost_poll_flush(&vs->vqs[index].vq.poll); } +/* Callers must hold dev mutex */ static void vhost_scsi_flush(struct vhost_scsi *vs) { struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ]; |