diff mbox series

[1/4] scsi/scsi_bus: switch search direction in scsi_device_find

Message ID 20200416203624.32366-2-mlevitsk@redhat.com (mailing list archive)
State New, archived
Headers show
Series RFC/WIP: Fix scsi devices plug/unplug races w.r.t virtio-scsi iothread | expand

Commit Message

Maxim Levitsky April 16, 2020, 8:36 p.m. UTC 
This change will allow us to convert the bus children list to RCU,
while not changing the logic of this function

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 hw/scsi/scsi-bus.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
index 1c980cab38..7bbc37acec 100644
--- a/hw/scsi/scsi-bus.c
+++ b/hw/scsi/scsi-bus.c
@@ -1584,7 +1584,7 @@  SCSIDevice *scsi_device_find(SCSIBus *bus, int channel, int id, int lun)
     BusChild *kid;
     SCSIDevice *target_dev = NULL;
 
-    QTAILQ_FOREACH_REVERSE(kid, &bus->qbus.children, sibling) {
+    QTAILQ_FOREACH(kid, &bus->qbus.children, sibling) {
         DeviceState *qdev = kid->child;
         SCSIDevice *dev = SCSI_DEVICE(qdev);
 
@@ -1592,7 +1592,15 @@  SCSIDevice *scsi_device_find(SCSIBus *bus, int channel, int id, int lun)
             if (dev->lun == lun) {
                 return dev;
             }
-            target_dev = dev;
+
+            /*
+             * If we don't find exact match (channel/bus/lun),
+             * we will return the first device which matches channel/bus
+             */
+
+            if (!target_dev) {
+                target_dev = dev;
+            }
         }
     }
     return target_dev;