vhost-scsi: Drop device mutex use in vhost_scsi_do_plug

We don't need the device mutex in vhost_scsi_do_plug because:
1. we have the vhost_scsi_mutex so the tpg->vhost_scsi pointer will not
change on us and the vhost_scsi can't be freed from under us if it was
set.
2. vhost_scsi_clear_endpoint will stop the virtqueues and flush them while
holding the vhost_scsi_mutex so we know once vhost_scsi_clear_endpoint
has completed that vhost_scsi_do_plug can't send new events and any
queued ones have completed.

So this patch drops the device mutex use in vhost_scsi_do_plug.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230321020624.13323-5-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 502d6803df0beb52d566491d7b40e41e215eb3e5..c945136ecf18563e61b1835cfa77c718fbdb9673 100644 (file)
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -2003,8 +2003,6 @@ vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
        if (!vs)
                return;
 
-       mutex_lock(&vs->dev.mutex);
-
        if (plug)
                reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
        else
@@ -2016,7 +2014,6 @@ vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
                vhost_scsi_send_evt(vs, tpg, lun,
                                   VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
        mutex_unlock(&vq->mutex);
-       mutex_unlock(&vs->dev.mutex);
 }
 
 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)