[TAPDISK] unlock sector on error case

Signed-off-by: Jake Wires <jwires@xensource.com>

diff --git a/tools/blktap/drivers/block-qcow.c b/tools/blktap/drivers/block-qcow.c
index 36f77e6f053ad68f723ef0bbbe794a447fd3d679..b0822f729df9f46115969fa0f5fde834ec8c747a 100644 (file)
--- a/tools/blktap/drivers/block-qcow.c
+++ b/tools/blktap/drivers/block-qcow.c
@@ -1057,6 +1057,7 @@ int tdqcow_queue_write(struct disk_driver *dd, uint64_t sector,
                                                    index_in_cluster+n);
                if (!cluster_offset) {
                        DPRINTF("Ooops, no write cluster offset!\n");
+                       aio_unlock(s, sector);
                        return cb(dd, -EIO, sector, nb_sectors, id, private);
                }