Function destroy_devl

freebsd/kern/kern_conf.c:1094–1194

}

static void
destroy_devl(struct cdev *dev)
{
	struct cdevsw *csw;
	struct cdev_privdata *p;
	struct cdev_priv *cdp;

	dev_lock_assert_locked();
	KASSERT(dev->si_flags & SI_NAMED,
	    ("WARNING: Driver mistake: destroy_dev on %d\n", dev2unit(dev)));
	KASSERT((dev->si_flags & SI_ETERNAL) == 0,
	    ("WARNING: Driver mistake: destroy_dev on eternal %d\n",
	     dev2unit(dev)));

	cdp = cdev2priv(dev);
	if ((cdp->cdp_flags & CDP_UNREF_DTR) == 0) {
		/*
		 * Avoid race with dev_rel(), e.g. from the populate
		 * loop.  If CDP_UNREF_DTR flag is set, the reference
		 * to be dropped at the end of destroy_devl() was
		 * already taken by delist_dev_locked().
		 */
		dev_refl(dev);

		devfs_destroy(dev);
	}

	/* Remove name marking */
	dev->si_flags &= ~SI_NAMED;

	/* If we are a child, remove us from the parents list */
	if (dev->si_flags & SI_CHILD) {
		LIST_REMOVE(dev, si_siblings);
		dev->si_flags &= ~SI_CHILD;
	}

	/* Kill our children */
	while (!LIST_EMPTY(&dev->si_children))
		destroy_devl(LIST_FIRST(&dev->si_children));

	/* Remove from clone list */
	if (dev->si_flags & SI_CLONELIST) {
		LIST_REMOVE(dev, si_clone);
		dev->si_flags &= ~SI_CLONELIST;
	}

	mtx_lock(&cdp->cdp_threadlock);
	csw = dev->si_devsw;
	dev->si_devsw = NULL;	/* already NULL for SI_ALIAS */
	while (csw != NULL && csw->d_purge != NULL && dev->si_threadcount) {
		csw->d_purge(dev);
		mtx_unlock(&cdp->cdp_threadlock);
		msleep(csw, &devmtx, PRIBIO, "devprg", hz/10);
		mtx_lock(&cdp->cdp_threadlock);
		if (dev->si_threadcount)
			printf("Still %lu threads in %s\n",
			    dev->si_threadcount, devtoname(dev));
	}