quorum: validate vote threshold against num_children even if read-pattern is fifo

We need to use threshold to check if too many write operation fails.
If threshold is larger than num children, we always get write error
event even if all write operations success.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Message-id: 55962F72.3060003@cn.fujitsu.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
diff --git a/block/quorum.c b/block/quorum.c
index 2f6c45f..8fe53b4 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -889,6 +889,12 @@
     }
 
     s->threshold = qemu_opt_get_number(opts, QUORUM_OPT_VOTE_THRESHOLD, 0);
+    /* and validate it against s->num_children */
+    ret = quorum_valid_threshold(s->threshold, s->num_children, &local_err);
+    if (ret < 0) {
+        goto exit;
+    }
+
     ret = parse_read_pattern(qemu_opt_get(opts, QUORUM_OPT_READ_PATTERN));
     if (ret < 0) {
         error_setg(&local_err, "Please set read-pattern as fifo or quorum");
@@ -897,12 +903,6 @@
     s->read_pattern = ret;
 
     if (s->read_pattern == QUORUM_READ_PATTERN_QUORUM) {
-        /* and validate it against s->num_children */
-        ret = quorum_valid_threshold(s->threshold, s->num_children, &local_err);
-        if (ret < 0) {
-            goto exit;
-        }
-
         /* is the driver in blkverify mode */
         if (qemu_opt_get_bool(opts, QUORUM_OPT_BLKVERIFY, false) &&
             s->num_children == 2 && s->threshold == 2) {