From 25f78d9e2de528473d52acfcf7acdfb64e3453d4 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Thu, 10 Jun 2021 15:05:34 +0300 Subject: [PATCH] block: move supports_backing check to bdrv_set_file_or_backing_noperm() Move supports_backing check of bdrv_reopen_parse_backing to called (through bdrv_set_backing_noperm()) bdrv_set_file_or_backing_noperm() function. The check applies to general case, so it's appropriate for bdrv_set_file_or_backing_noperm(). We have to declare backing support for two test drivers, otherwise new check fails. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-Id: <20210610120537.196183-7-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf --- block.c | 29 +++++++++++++++-------------- tests/unit/test-bdrv-drain.c | 1 + tests/unit/test-bdrv-graph-mod.c | 1 + 3 files changed, 17 insertions(+), 14 deletions(-) diff --git a/block.c b/block.c index d047cae43c..0a73335380 100644 --- a/block.c +++ b/block.c @@ -3152,6 +3152,14 @@ static int bdrv_set_file_or_backing_noperm(BlockDriverState *parent_bs, return -EPERM; } + if (is_backing && !parent_bs->drv->is_filter && + !parent_bs->drv->supports_backing) + { + error_setg(errp, "Driver '%s' of node '%s' does not support backing " + "files", parent_bs->drv->format_name, parent_bs->node_name); + return -EINVAL; + } + if (parent_bs->drv->is_filter) { role = BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; } else if (is_backing) { @@ -4278,20 +4286,13 @@ static int bdrv_reopen_parse_backing(BDRVReopenState *reopen_state, } } - /* - * Ensure that @bs can really handle backing files, because we are - * about to give it one (or swap the existing one) - */ - if (bs->drv->is_filter) { - /* Filters always have a file or a backing child */ - if (!bs->backing) { - error_setg(errp, "'%s' is a %s filter node that does not support a " - "backing child", bs->node_name, bs->drv->format_name); - return -EINVAL; - } - } else if (!bs->drv->supports_backing) { - error_setg(errp, "Driver '%s' of node '%s' does not support backing " - "files", bs->drv->format_name, bs->node_name); + if (bs->drv->is_filter && !bs->backing) { + /* + * Filters always have a file or a backing child, so we are trying to + * change wrong child + */ + error_setg(errp, "'%s' is a %s filter node that does not support a " + "backing child", bs->node_name, bs->drv->format_name); return -EINVAL; } diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index 892f7f47d8..ce071b5fc5 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -95,6 +95,7 @@ static int bdrv_test_change_backing_file(BlockDriverState *bs, static BlockDriver bdrv_test = { .format_name = "test", .instance_size = sizeof(BDRVTestState), + .supports_backing = true, .bdrv_close = bdrv_test_close, .bdrv_co_preadv = bdrv_test_co_preadv, diff --git a/tests/unit/test-bdrv-graph-mod.c b/tests/unit/test-bdrv-graph-mod.c index 88f25c0cdb..a6e3bb79be 100644 --- a/tests/unit/test-bdrv-graph-mod.c +++ b/tests/unit/test-bdrv-graph-mod.c @@ -41,6 +41,7 @@ static void no_perm_default_perms(BlockDriverState *bs, BdrvChild *c, static BlockDriver bdrv_no_perm = { .format_name = "no-perm", + .supports_backing = true, .bdrv_child_perm = no_perm_default_perms, };