block/nbd: fix how state is cleared on nbd_open() failure paths

We have two "return error" paths in nbd_open() after
nbd_process_options(). Actually we should call nbd_clear_bdrvstate()
on these paths. Interesting that nbd_process_options() calls
nbd_clear_bdrvstate() by itself.

Let's fix leaks and refactor things to be more obvious:

- intialize yank at top of nbd_open()
- move yank cleanup to nbd_clear_bdrvstate()
- refactor nbd_open() so that all failure paths except for
  yank-register goes through nbd_clear_bdrvstate()

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210610100802.5888-4-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2021-06-10 13:07:33 +03:00 committed by Eric Blake
parent 3687ad4903
commit bbba1c376b

View File

@ -152,8 +152,12 @@ static void nbd_co_establish_connection_cancel(BlockDriverState *bs,
static int nbd_client_handshake(BlockDriverState *bs, Error **errp);
static void nbd_yank(void *opaque);
static void nbd_clear_bdrvstate(BDRVNBDState *s)
static void nbd_clear_bdrvstate(BlockDriverState *bs)
{
BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
yank_unregister_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name));
object_unref(OBJECT(s->tlscreds));
qapi_free_SocketAddress(s->saddr);
s->saddr = NULL;
@ -2275,9 +2279,6 @@ static int nbd_process_options(BlockDriverState *bs, QDict *options,
ret = 0;
error:
if (ret < 0) {
nbd_clear_bdrvstate(s);
}
qemu_opts_del(opts);
return ret;
}
@ -2288,11 +2289,6 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
int ret;
BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
ret = nbd_process_options(bs, options, errp);
if (ret < 0) {
return ret;
}
s->bs = bs;
qemu_co_mutex_init(&s->send_mutex);
qemu_co_queue_init(&s->free_sema);
@ -2301,20 +2297,23 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
return -EEXIST;
}
ret = nbd_process_options(bs, options, errp);
if (ret < 0) {
goto fail;
}
/*
* establish TCP connection, return error if it fails
* TODO: Configurable retry-until-timeout behaviour.
*/
if (nbd_establish_connection(bs, s->saddr, errp) < 0) {
yank_unregister_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name));
return -ECONNREFUSED;
ret = -ECONNREFUSED;
goto fail;
}
ret = nbd_client_handshake(bs, errp);
if (ret < 0) {
yank_unregister_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name));
nbd_clear_bdrvstate(s);
return ret;
goto fail;
}
/* successfully connected */
s->state = NBD_CLIENT_CONNECTED;
@ -2326,6 +2325,10 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
aio_co_schedule(bdrv_get_aio_context(bs), s->connection_co);
return 0;
fail:
nbd_clear_bdrvstate(bs);
return ret;
}
static int nbd_co_flush(BlockDriverState *bs)
@ -2369,11 +2372,8 @@ static void nbd_refresh_limits(BlockDriverState *bs, Error **errp)
static void nbd_close(BlockDriverState *bs)
{
BDRVNBDState *s = bs->opaque;
nbd_client_close(bs);
yank_unregister_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name));
nbd_clear_bdrvstate(s);
nbd_clear_bdrvstate(bs);
}
/*