endio
bio->bi_end_io = endio;
struct io_notify *endio = context;
writecache_error(endio->wc, -EIO, "error writing metadata");
BUG_ON(atomic_read(&endio->count) <= 0);
if (atomic_dec_and_test(&endio->count))
complete(&endio->c);
struct io_notify endio = {
COMPLETION_INITIALIZER_ONSTACK(endio.c),
atomic_inc(&endio.count);
req.notify.context = &endio;
writecache_notify_io(0, &endio);
wait_for_completion_io(&endio.c);
dm_endio_fn endio = likely(ti != NULL) ? ti->type->end_io : NULL;
if (endio) {
int r = endio(ti, bio, &error);