commit 6c5a42ac344306bb3711140a3267c61276c1567b
author Peter Lieven <pl@kamp.de> Mon Oct 27 10:18:46 2014 +0100
committer Stefan Hajnoczi <stefanha@redhat.com> Mon Nov 03 09:48:41 2014 +0000
tree e1460a5f23274d81ed881000d2603a2dd0377d8a
parent 52f6fa1430209125d1c13fec7d6bbb501aedf322

block: avoid creating oversized writes in multiwrite_merge

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

block.c

diff --git a/block.c b/block.c
index 76fcc1d..4179341 100644
--- a/block.c
+++ b/block.c
@@ -4446,6 +4446,11 @@
             merge = 0;
         }
 
+        if (bs->bl.max_transfer_length && reqs[outidx].nb_sectors +
+            reqs[i].nb_sectors > bs->bl.max_transfer_length) {
+            merge = 0;
+        }
+
         if (merge) {
             size_t size;
             QEMUIOVector *qiov = g_malloc0(sizeof(*qiov));