scsi: do not call transfer_data after canceling a request
Otherwise, if cancellation is "faked" by the AIO layer and goes
through qemu_aio_flush, the whole request is completed synchronously
during scsi_req_cancel.
Using the enqueued flag would work here, but not in the next patches,
so I'm introducing a new io_canceled flag. That's because scsi_req_data
is a synchronous callback and the enqueued flag might be reset by the
time it returns. scsi-disk cannot unref the request until after calling
scsi_req_data.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/trace-events b/trace-events
index a888055..56443af 100644
--- a/trace-events
+++ b/trace-events
@@ -278,6 +278,7 @@
# hw/scsi-bus.c
scsi_req_alloc(int target, int lun, int tag) "target %d lun %d tag %d"
scsi_req_data(int target, int lun, int tag, int len) "target %d lun %d tag %d len %d"
+scsi_req_data_canceled(int target, int lun, int tag, int len) "target %d lun %d tag %d len %d"
scsi_req_dequeue(int target, int lun, int tag) "target %d lun %d tag %d"
scsi_req_continue(int target, int lun, int tag) "target %d lun %d tag %d"
scsi_req_parsed(int target, int lun, int tag, int cmd, int mode, int xfer) "target %d lun %d tag %d command %d dir %d length %d"
