From bf0e9a6374d872bde330fb3c4994697250ef235b Mon Sep 17 00:00:00 2001
From: Fam Zheng <famz@redhat.com>
Date: Tue, 13 Mar 2018 15:27:54 +0100
Subject: [PATCH 1/4] block: Fix flags in reopen queue

RH-Author: Fam Zheng <famz@redhat.com>
Message-id: <20180313152755.31475-2-famz@redhat.com>
Patchwork-id: 79273
O-Subject: [RHV7.5 qemu-kvm-ma PATCH v4 1/2] block: Fix flags in reopen queue
Bugzilla: 1557206
RH-Acked-by: Max Reitz <mreitz@redhat.com>
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

Reopen flags are not synchronized according to the
bdrv_reopen_queue_child precedence until bdrv_reopen_prepare. It is a
bit too late: we already check the consistency in bdrv_check_perm before
that.

This fixes the bug that when bdrv_reopen a RO node as RW, the flags for
backing child are wrong. Before, we could recurse with flags.rw=1; now,
role->inherit_options + update_flags_from_options will make sure to
clear the bit when necessary.  Note that this will not clear an
explicitly set bit, as in the case of parallel block jobs (e.g.
test_stream_parallel in 030), because the explicit options include
'read-only=false' (for an intermediate node used by a different job).

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 block.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/block.c b/block.c
index ca8a46b..a1084e7 100644
--- a/block.c
+++ b/block.c
@@ -2759,8 +2759,16 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue,
 
     /* Inherit from parent node */
     if (parent_options) {
+        QemuOpts *opts;
+        QDict *options_copy;
         assert(!flags);
         role->inherit_options(&flags, options, parent_flags, parent_options);
+        options_copy = qdict_clone_shallow(options);
+        opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort);
+        qemu_opts_absorb_qdict(opts, options_copy, NULL);
+        update_flags_from_options(&flags, opts);
+        qemu_opts_del(opts);
+        QDECREF(options_copy);
     }
 
     /* Old values are used for options that aren't set yet */
-- 
1.8.3.1