hw/xen_disk: ioreq not finished on error

Bug fix: routines 'ioreq_runio_qemu_sync' and 'ioreq_runio_qemu_aio'
won't call 'ioreq_unmap' or 'ioreq_finish' on errors, leaving ioreq in
the blkdev->inflight list and a leak.

Signed-off-by: Feiran Zheng <famcool@gmail.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

hw/xen_disk.c

diff --git a/hw/xen_disk.c b/hw/xen_disk.c
index 445bf03..558bf8a 100644
--- a/hw/xen_disk.c
+++ b/hw/xen_disk.c
@@ -310,7 +310,7 @@
     off_t pos;
 
     if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1)
-	goto err;
+	goto err_no_map;
     if (ioreq->presync)
 	bdrv_flush(blkdev->bs);
 
@@ -364,6 +364,9 @@
     return 0;
 
 err:
+    ioreq_unmap(ioreq);
+err_no_map:
+    ioreq_finish(ioreq);
     ioreq->status = BLKIF_RSP_ERROR;
     return -1;
 }
@@ -393,7 +396,7 @@
     struct XenBlkDev *blkdev = ioreq->blkdev;
 
     if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1)
-	goto err;
+	goto err_no_map;
 
     ioreq->aio_inflight++;
     if (ioreq->presync)
@@ -427,6 +430,9 @@
     return 0;
 
 err:
+    ioreq_unmap(ioreq);
+err_no_map:
+    ioreq_finish(ioreq);
     ioreq->status = BLKIF_RSP_ERROR;
     return -1;
 }