Function cache_purge_impl

freebsd/kern/vfs_cache.c:2623–2660

* Remove all entries from and to a particular vnode. */

 * Remove all entries from and to a particular vnode.
 */
static void
cache_purge_impl(struct vnode *vp)
{
	struct cache_freebatch batch;
	struct namecache *ncp;
	struct mtx *vlp, *vlp2;

	TAILQ_INIT(&batch);
	vlp = VP2VNODELOCK(vp);
	vlp2 = NULL;
	mtx_lock(vlp);
retry:
	while (!LIST_EMPTY(&vp->v_cache_src)) {
		ncp = LIST_FIRST(&vp->v_cache_src);
		if (!cache_zap_locked_vnode_kl2(ncp, vp, &vlp2))
			goto retry;
		TAILQ_INSERT_TAIL(&batch, ncp, nc_dst);
	}
	while (!TAILQ_EMPTY(&vp->v_cache_dst)) {
		ncp = TAILQ_FIRST(&vp->v_cache_dst);
		if (!cache_zap_locked_vnode_kl2(ncp, vp, &vlp2))
			goto retry;
		TAILQ_INSERT_TAIL(&batch, ncp, nc_dst);
	}
	ncp = vp->v_cache_dd;
	if (ncp != NULL) {
		KASSERT(ncp->nc_flag & NCF_ISDOTDOT,
		   ("lost dotdot link"));
		if (!cache_zap_locked_vnode_kl2(ncp, vp, &vlp2))
			goto retry;
		TAILQ_INSERT_TAIL(&batch, ncp, nc_dst);
	}
	KASSERT(vp->v_cache_dd == NULL, ("incomplete purge"));
	mtx_unlock(vlp);
	if (vlp2 != NULL)
		mtx_unlock(vlp2);
	cache_free_batch(&batch);
}

/*
 * Opportunistic check to see if there is anything to do.