Exemplo n.º 1
0
/*
 * Look for the request in the cache
 * If found then
 *    return action and optionally reply
 * else
 *    insert it in the cache
 *
 * The rules are as follows:
 * - if in progress, return DROP request
 * - if completed within DELAY of the current time, return DROP it
 * - if completed a longer time ago return REPLY if the reply was cached or
 *   return DOIT
 * Update/add new request at end of lru list
 */
int
nfsrv_getcache(struct nfsrv_descript *nd, struct nfssvc_sock *slp,
	       struct mbuf **repp)
{
	struct nfsrvcache *rp;
	struct mbuf *mb;
	struct sockaddr_in *saddr;
	caddr_t bpos;
	int ret;

	/*
	 * Don't cache recent requests for reliable transport protocols.
	 * (Maybe we should for the case of a reconnect, but..)
	 */
	if (!nd->nd_nam2)
		return (RC_DOIT);

	lwkt_gettoken(&srvcache_token);
loop:
	for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != NULL;
	    rp = rp->rc_hash.le_next) {
	    if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc &&
		netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) {
		        NFS_DPF(RC, ("H%03x", rp->rc_xid & 0xfff));
			if ((rp->rc_flag & RC_LOCKED) != 0) {
				rp->rc_flag |= RC_WANTED;
				tsleep((caddr_t)rp, 0, "nfsrc", 0);
				goto loop;
			}
			rp->rc_flag |= RC_LOCKED;
			/* If not at end of LRU chain, move it there */
			if (TAILQ_NEXT(rp, rc_lru) != NULL) {
				TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
				TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);
			}
			if (rp->rc_state == RC_UNUSED)
				panic("nfsrv cache");
			if (rp->rc_state == RC_INPROG) {
				nfsstats.srvcache_inproghits++;
				ret = RC_DROPIT;
			} else if (rp->rc_flag & RC_REPSTATUS) {
				nfsstats.srvcache_nonidemdonehits++;
				nfs_rephead(0, nd, slp, rp->rc_status,
					    repp, &mb, &bpos);
				ret = RC_REPLY;
			} else if (rp->rc_flag & RC_REPMBUF) {
				nfsstats.srvcache_nonidemdonehits++;
				*repp = m_copym(rp->rc_reply, 0, M_COPYALL,
						MB_WAIT);
				ret = RC_REPLY;
			} else {
				nfsstats.srvcache_idemdonehits++;
				rp->rc_state = RC_INPROG;
				ret = RC_DOIT;
			}
			rp->rc_flag &= ~RC_LOCKED;
			if (rp->rc_flag & RC_WANTED) {
				rp->rc_flag &= ~RC_WANTED;
				wakeup((caddr_t)rp);
			}
			lwkt_reltoken(&srvcache_token);
			return (ret);
		}
	}

	nfsstats.srvcache_misses++;
	NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff));
	if (numnfsrvcache < desirednfsrvcache) {
		rp = kmalloc((u_long)sizeof *rp, M_NFSD, M_WAITOK | M_ZERO);
		numnfsrvcache++;
		rp->rc_flag = RC_LOCKED;
	} else {
		rp = TAILQ_FIRST(&nfsrvlruhead);
		while ((rp->rc_flag & RC_LOCKED) != 0) {
			rp->rc_flag |= RC_WANTED;
			tsleep((caddr_t)rp, 0, "nfsrc", 0);
			rp = TAILQ_FIRST(&nfsrvlruhead);
		}
		rp->rc_flag |= RC_LOCKED;
		LIST_REMOVE(rp, rc_hash);
		TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
		if (rp->rc_flag & RC_REPMBUF) {
			m_freem(rp->rc_reply);
			rp->rc_reply = NULL;
			rp->rc_flag &= ~RC_REPMBUF;
		}
		if (rp->rc_flag & RC_NAM) {
			kfree(rp->rc_nam, M_SONAME);
			rp->rc_nam = NULL;
			rp->rc_flag &= ~RC_NAM;
		}
	}
	TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);

	rp->rc_state = RC_INPROG;
	rp->rc_xid = nd->nd_retxid;
	saddr = (struct sockaddr_in *)nd->nd_nam;
	switch (saddr->sin_family) {
	case AF_INET:
		rp->rc_flag |= RC_INETADDR;
		rp->rc_inetaddr = saddr->sin_addr.s_addr;
		break;
	case AF_ISO:
	default:
		rp->rc_flag |= RC_NAM;
		rp->rc_nam = dup_sockaddr(nd->nd_nam);
		break;
	};
	rp->rc_proc = nd->nd_procnum;
	LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash);
	rp->rc_flag &= ~RC_LOCKED;
	if (rp->rc_flag & RC_WANTED) {
		rp->rc_flag &= ~RC_WANTED;
		wakeup((caddr_t)rp);
	}
	lwkt_reltoken(&srvcache_token);

	return (RC_DOIT);
}
Exemplo n.º 2
0
/*
 * Look for the request in the cache
 * If found then
 *    return action and optionally reply
 * else
 *    insert it in the cache
 *
 * The rules are as follows:
 * - if in progress, return DROP request
 * - if completed within DELAY of the current time, return DROP it
 * - if completed a longer time ago return REPLY if the reply was cached or
 *   return DOIT
 * Update/add new request at end of lru list
 */
int
nfsrv_getcache(struct nfsrv_descript *nd, struct nfssvc_sock *slp,
    struct mbuf **repp)
{
	struct nfsrvhash *hash;
	struct nfsrvcache *rp;
	struct mbuf *mb;
	struct sockaddr_in *saddr;
	int ret;

	/*
	 * Don't cache recent requests for reliable transport protocols.
	 * (Maybe we should for the case of a reconnect, but..)
	 */
	if (!nd->nd_nam2)
		return (RC_DOIT);

	rp = nfsrv_lookupcache(nd);
	if (rp) {
		/* If not at end of LRU chain, move it there */
		if (TAILQ_NEXT(rp, rc_lru)) {
			TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
			TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);
		}
		if (rp->rc_state == RC_UNUSED)
			panic("nfsrv cache");
		if (rp->rc_state == RC_INPROG) {
			nfsstats.srvcache_inproghits++;
			ret = RC_DROPIT;
		} else if (rp->rc_flag & RC_REPSTATUS) {
			nfsstats.srvcache_nonidemdonehits++;
			nfs_rephead(0, nd, slp, rp->rc_status, repp, &mb);
			ret = RC_REPLY;
		} else if (rp->rc_flag & RC_REPMBUF) {
			nfsstats.srvcache_nonidemdonehits++;
			*repp = m_copym(rp->rc_reply, 0, M_COPYALL, M_WAIT);
			ret = RC_REPLY;
		} else {
			nfsstats.srvcache_idemdonehits++;
			rp->rc_state = RC_INPROG;
			ret = RC_DOIT;
		}
		rp->rc_flag &= ~RC_LOCKED;
		if (rp->rc_flag & RC_WANTED) {
			rp->rc_flag &= ~RC_WANTED;
			wakeup(rp);
		}
		return (ret);
	}

	nfsstats.srvcache_misses++;
	if (numnfsrvcache < desirednfsrvcache) {
		rp = malloc(sizeof(*rp), M_NFSD, M_WAITOK|M_ZERO);
		numnfsrvcache++;
		rp->rc_flag = RC_LOCKED;
	} else {
		rp = TAILQ_FIRST(&nfsrvlruhead);
		while ((rp->rc_flag & RC_LOCKED) != 0) {
			rp->rc_flag |= RC_WANTED;
			tsleep(rp, PZERO-1, "nfsrc", 0);
			rp = TAILQ_FIRST(&nfsrvlruhead);
		}
		rp->rc_flag |= RC_LOCKED;
		LIST_REMOVE(rp, rc_hash);
		TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
		nfsrv_cleanentry(rp);
		rp->rc_flag &= (RC_LOCKED | RC_WANTED);
	}
	TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);
	rp->rc_state = RC_INPROG;
	rp->rc_xid = nd->nd_retxid;
	saddr = mtod(nd->nd_nam, struct sockaddr_in *);
	switch (saddr->sin_family) {
	case AF_INET:
		rp->rc_flag |= RC_INETADDR;
		rp->rc_inetaddr = saddr->sin_addr.s_addr;
		break;
	default:
		rp->rc_flag |= RC_NAM;
		rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT);
		break;
	};
	rp->rc_proc = nd->nd_procnum;
	hash = NFSRCHASH(nd->nd_retxid);
	LIST_INSERT_HEAD(hash, rp, rc_hash);
	rp->rc_flag &= ~RC_LOCKED;
	if (rp->rc_flag & RC_WANTED) {
		rp->rc_flag &= ~RC_WANTED;
		wakeup(rp);
	}
	return (RC_DOIT);
}