block: Mark bdrv_unref_child() GRAPH_WRLOCK

Instead of taking the writer lock internally, require callers to already
hold it when calling bdrv_unref_child(). These callers will typically
already hold the graph lock once the locking work is completed, which
means that they can't call functions that take it internally.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230911094620.45040-21-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2023-09-11 11:46:19 +02:00
parent ede01e4635
commit 32a8aba37e
10 changed files with 50 additions and 8 deletions

View file

@ -1880,7 +1880,7 @@ qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
g_free(s->image_data_file);
if (open_data_file && has_data_file(bs)) {
bdrv_graph_co_rdunlock();
bdrv_unref_child(bs, s->data_file);
bdrv_co_unref_child(bs, s->data_file);
bdrv_graph_co_rdlock();
s->data_file = NULL;
}
@ -2790,7 +2790,9 @@ static void qcow2_do_close(BlockDriverState *bs, bool close_data_file)
g_free(s->image_backing_format);
if (close_data_file && has_data_file(bs)) {
bdrv_graph_wrlock(NULL);
bdrv_unref_child(bs, s->data_file);
bdrv_graph_wrunlock();
s->data_file = NULL;
}