2 * Block node graph modifications tests
4 * Copyright (c) 2019 Virtuozzo International GmbH. All rights reserved.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include "qemu/osdep.h"
22 #include "qapi/error.h"
23 #include "block/block_int.h"
24 #include "sysemu/block-backend.h"
26 static BlockDriver bdrv_pass_through
= {
27 .format_name
= "pass-through",
28 .bdrv_child_perm
= bdrv_filter_default_perms
,
31 static void no_perm_default_perms(BlockDriverState
*bs
, BdrvChild
*c
,
32 const BdrvChildRole
*role
,
33 BlockReopenQueue
*reopen_queue
,
34 uint64_t perm
, uint64_t shared
,
35 uint64_t *nperm
, uint64_t *nshared
)
38 *nshared
= BLK_PERM_ALL
;
41 static BlockDriver bdrv_no_perm
= {
42 .format_name
= "no-perm",
43 .bdrv_child_perm
= no_perm_default_perms
,
46 static BlockDriverState
*no_perm_node(const char *name
)
48 return bdrv_new_open_driver(&bdrv_no_perm
, name
, BDRV_O_RDWR
, &error_abort
);
51 static BlockDriverState
*pass_through_node(const char *name
)
53 return bdrv_new_open_driver(&bdrv_pass_through
, name
,
54 BDRV_O_RDWR
, &error_abort
);
58 * test_update_perm_tree
60 * When checking node for a possibility to update permissions, it's subtree
61 * should be correctly checked too. New permissions for each node should be
62 * calculated and checked in context of permissions of other nodes. If we
63 * check new permissions of the node only in context of old permissions of
64 * its neighbors, we can finish up with wrong permission graph.
66 * This test firstly create the following graph:
72 * | shared: except write
74 * +-------------------+ +----------------+
75 * | passtrough filter |---------->| null-co node |
76 * +-------------------+ +----------------+
79 * and then, tries to append filter under node. Expected behavior: fail.
80 * Otherwise we'll get the following picture, with two BdrvChild'ren, having
81 * write permission to one node, without actually sharing it.
88 * | shared: except write
90 * +-------------------+
91 * | passtrough filter |
92 * +-------------------+
94 * perm: write, read | | perm: write, read
95 * shared: except write | | shared: except write
101 static void test_update_perm_tree(void)
103 Error
*local_err
= NULL
;
105 BlockBackend
*root
= blk_new(qemu_get_aio_context(),
106 BLK_PERM_WRITE
| BLK_PERM_CONSISTENT_READ
,
107 BLK_PERM_ALL
& ~BLK_PERM_WRITE
);
108 BlockDriverState
*bs
= no_perm_node("node");
109 BlockDriverState
*filter
= pass_through_node("filter");
111 blk_insert_bs(root
, bs
, &error_abort
);
113 bdrv_attach_child(filter
, bs
, "child", &child_file
, &error_abort
);
115 bdrv_append(filter
, bs
, &local_err
);
117 g_assert_nonnull(local_err
);
118 error_free(local_err
);
124 * test_should_update_child
126 * Test that bdrv_replace_node, and concretely should_update_child
127 * do the right thing, i.e. not creating loops on the graph.
129 * The test does the following:
132 * +------+ +--------+
133 * | root | | filter |
134 * +------+ +--------+
138 * +------+ +--------+
139 * | node |<---------| target |
140 * +------+ backing +--------+
142 * 2. Append @filter above @node. If should_update_child works correctly,
143 * it understands, that backing child of @target should not be updated,
144 * as it will create a loop on node graph. Resulting picture should
145 * be the left one, not the right:
153 * +--------+ target +--------+ target
154 * | filter |--------------+ | filter |--------------+
155 * +--------+ | +--------+ |
157 * backing| | backing| | +--------+
158 * v v | +-----------| target |
159 * +------+ +--------+ v backing +--------+
160 * | node |<---------| target | +------+
161 * +------+ backing +--------+ | node |
164 * (good picture) (bad picture)
167 static void test_should_update_child(void)
169 BlockBackend
*root
= blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL
);
170 BlockDriverState
*bs
= no_perm_node("node");
171 BlockDriverState
*filter
= no_perm_node("filter");
172 BlockDriverState
*target
= no_perm_node("target");
174 blk_insert_bs(root
, bs
, &error_abort
);
176 bdrv_set_backing_hd(target
, bs
, &error_abort
);
178 g_assert(target
->backing
->bs
== bs
);
179 bdrv_attach_child(filter
, target
, "target", &child_file
, &error_abort
);
180 bdrv_append(filter
, bs
, &error_abort
);
181 g_assert(target
->backing
->bs
== bs
);
187 int main(int argc
, char *argv
[])
190 qemu_init_main_loop(&error_abort
);
192 g_test_init(&argc
, &argv
, NULL
);
194 g_test_add_func("/bdrv-graph-mod/update-perm-tree", test_update_perm_tree
);
195 g_test_add_func("/bdrv-graph-mod/should-update-child",
196 test_should_update_child
);