nlm_prot_impl.c revision 303173
1/*-
2 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
3 * Authors: Doug Rabson <dfr@rabson.org>
4 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include "opt_inet6.h"
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: stable/10/sys/nlm/nlm_prot_impl.c 303173 2016-07-22 03:09:47Z sbruno $");
32
33#include <sys/param.h>
34#include <sys/fail.h>
35#include <sys/fcntl.h>
36#include <sys/kernel.h>
37#include <sys/kthread.h>
38#include <sys/lockf.h>
39#include <sys/malloc.h>
40#include <sys/mount.h>
41#if __FreeBSD_version >= 700000
42#include <sys/priv.h>
43#endif
44#include <sys/proc.h>
45#include <sys/socket.h>
46#include <sys/socketvar.h>
47#include <sys/syscall.h>
48#include <sys/sysctl.h>
49#include <sys/sysent.h>
50#include <sys/syslog.h>
51#include <sys/sysproto.h>
52#include <sys/systm.h>
53#include <sys/taskqueue.h>
54#include <sys/unistd.h>
55#include <sys/vnode.h>
56
57#include <nfs/nfsproto.h>
58#include <nfs/nfs_lock.h>
59
60#include <nlm/nlm_prot.h>
61#include <nlm/sm_inter.h>
62#include <nlm/nlm.h>
63#include <rpc/rpc_com.h>
64#include <rpc/rpcb_prot.h>
65
66MALLOC_DEFINE(M_NLM, "NLM", "Network Lock Manager");
67
68/*
69 * If a host is inactive (and holds no locks) for this amount of
70 * seconds, we consider it idle and stop tracking it.
71 */
72#define NLM_IDLE_TIMEOUT	30
73
74/*
75 * We check the host list for idle every few seconds.
76 */
77#define NLM_IDLE_PERIOD		5
78
79/*
80 * We only look for GRANTED_RES messages for a little while.
81 */
82#define NLM_EXPIRE_TIMEOUT	10
83
84/*
85 * Support for sysctl vfs.nlm.sysid
86 */
87static SYSCTL_NODE(_vfs, OID_AUTO, nlm, CTLFLAG_RW, NULL,
88    "Network Lock Manager");
89static SYSCTL_NODE(_vfs_nlm, OID_AUTO, sysid, CTLFLAG_RW, NULL, "");
90
91/*
92 * Syscall hooks
93 */
94static int nlm_syscall_offset = SYS_nlm_syscall;
95static struct sysent nlm_syscall_prev_sysent;
96#if __FreeBSD_version < 700000
97static struct sysent nlm_syscall_sysent = {
98	(sizeof(struct nlm_syscall_args) / sizeof(register_t)) | SYF_MPSAFE,
99	(sy_call_t *) nlm_syscall
100};
101#else
102MAKE_SYSENT(nlm_syscall);
103#endif
104static bool_t nlm_syscall_registered = FALSE;
105
106/*
107 * Debug level passed in from userland. We also support a sysctl hook
108 * so that it can be changed on a live system.
109 */
110static int nlm_debug_level;
111SYSCTL_INT(_debug, OID_AUTO, nlm_debug, CTLFLAG_RW, &nlm_debug_level, 0, "");
112
113#define NLM_DEBUG(_level, args...)			\
114	do {						\
115		if (nlm_debug_level >= (_level))	\
116			log(LOG_DEBUG, args);		\
117	} while(0)
118#define NLM_ERR(args...)			\
119	do {					\
120		log(LOG_ERR, args);		\
121	} while(0)
122
123/*
124 * Grace period handling. The value of nlm_grace_threshold is the
125 * value of time_uptime after which we are serving requests normally.
126 */
127static time_t nlm_grace_threshold;
128
129/*
130 * We check for idle hosts if time_uptime is greater than
131 * nlm_next_idle_check,
132 */
133static time_t nlm_next_idle_check;
134
135/*
136 * A flag to indicate the server is already running.
137 */
138static int nlm_is_running;
139
140/*
141 * A socket to use for RPC - shared by all IPv4 RPC clients.
142 */
143static struct socket *nlm_socket;
144
145#ifdef INET6
146
147/*
148 * A socket to use for RPC - shared by all IPv6 RPC clients.
149 */
150static struct socket *nlm_socket6;
151
152#endif
153
154/*
155 * An RPC client handle that can be used to communicate with the local
156 * NSM.
157 */
158static CLIENT *nlm_nsm;
159
160/*
161 * An AUTH handle for the server's creds.
162 */
163static AUTH *nlm_auth;
164
165/*
166 * A zero timeval for sending async RPC messages.
167 */
168struct timeval nlm_zero_tv = { 0, 0 };
169
170/*
171 * The local NSM state number
172 */
173int nlm_nsm_state;
174
175
176/*
177 * A lock to protect the host list and waiting lock list.
178 */
179static struct mtx nlm_global_lock;
180
181/*
182 * Locks:
183 * (l)		locked by nh_lock
184 * (s)		only accessed via server RPC which is single threaded
185 * (g)		locked by nlm_global_lock
186 * (c)		const until freeing
187 * (a)		modified using atomic ops
188 */
189
190/*
191 * A pending client-side lock request, stored on the nlm_waiting_locks
192 * list.
193 */
194struct nlm_waiting_lock {
195	TAILQ_ENTRY(nlm_waiting_lock) nw_link; /* (g) */
196	bool_t		nw_waiting;	       /* (g) */
197	nlm4_lock	nw_lock;	       /* (c) */
198	union nfsfh	nw_fh;		       /* (c) */
199	struct vnode	*nw_vp;		       /* (c) */
200};
201TAILQ_HEAD(nlm_waiting_lock_list, nlm_waiting_lock);
202
203struct nlm_waiting_lock_list nlm_waiting_locks; /* (g) */
204
205/*
206 * A pending server-side asynchronous lock request, stored on the
207 * nh_pending list of the NLM host.
208 */
209struct nlm_async_lock {
210	TAILQ_ENTRY(nlm_async_lock) af_link; /* (l) host's list of locks */
211	struct task	af_task;	/* (c) async callback details */
212	void		*af_cookie;	/* (l) lock manager cancel token */
213	struct vnode	*af_vp;		/* (l) vnode to lock */
214	struct flock	af_fl;		/* (c) lock details */
215	struct nlm_host *af_host;	/* (c) host which is locking */
216	CLIENT		*af_rpc;	/* (c) rpc client to send message */
217	nlm4_testargs	af_granted;	/* (c) notification details */
218	time_t		af_expiretime;	/* (c) notification time */
219};
220TAILQ_HEAD(nlm_async_lock_list, nlm_async_lock);
221
222/*
223 * NLM host.
224 */
225enum nlm_host_state {
226	NLM_UNMONITORED,
227	NLM_MONITORED,
228	NLM_MONITOR_FAILED,
229	NLM_RECOVERING
230};
231
232struct nlm_rpc {
233	CLIENT		*nr_client;    /* (l) RPC client handle */
234	time_t		nr_create_time; /* (l) when client was created */
235};
236
237struct nlm_host {
238	struct mtx	nh_lock;
239	volatile u_int	nh_refs;       /* (a) reference count */
240	TAILQ_ENTRY(nlm_host) nh_link; /* (g) global list of hosts */
241	char		nh_caller_name[MAXNAMELEN]; /* (c) printable name of host */
242	uint32_t	nh_sysid;	 /* (c) our allocaed system ID */
243	char		nh_sysid_string[10]; /* (c) string rep. of sysid */
244	struct sockaddr_storage	nh_addr; /* (s) remote address of host */
245	struct nlm_rpc	nh_srvrpc;	 /* (l) RPC for server replies */
246	struct nlm_rpc	nh_clntrpc;	 /* (l) RPC for client requests */
247	rpcvers_t	nh_vers;	 /* (s) NLM version of host */
248	int		nh_state;	 /* (s) last seen NSM state of host */
249	enum nlm_host_state nh_monstate; /* (l) local NSM monitoring state */
250	time_t		nh_idle_timeout; /* (s) Time at which host is idle */
251	struct sysctl_ctx_list nh_sysctl; /* (c) vfs.nlm.sysid nodes */
252	uint32_t	nh_grantcookie;  /* (l) grant cookie counter */
253	struct nlm_async_lock_list nh_pending; /* (l) pending async locks */
254	struct nlm_async_lock_list nh_granted; /* (l) granted locks */
255	struct nlm_async_lock_list nh_finished; /* (l) finished async locks */
256};
257TAILQ_HEAD(nlm_host_list, nlm_host);
258
259static struct nlm_host_list nlm_hosts; /* (g) */
260static uint32_t nlm_next_sysid = 1;    /* (g) */
261
262static void	nlm_host_unmonitor(struct nlm_host *);
263
264struct nlm_grantcookie {
265	uint32_t	ng_sysid;
266	uint32_t	ng_cookie;
267};
268
269static inline uint32_t
270ng_sysid(struct netobj *src)
271{
272
273	return ((struct nlm_grantcookie *)src->n_bytes)->ng_sysid;
274}
275
276static inline uint32_t
277ng_cookie(struct netobj *src)
278{
279
280	return ((struct nlm_grantcookie *)src->n_bytes)->ng_cookie;
281}
282
283/**********************************************************************/
284
285/*
286 * Initialise NLM globals.
287 */
288static void
289nlm_init(void *dummy)
290{
291	int error;
292
293	mtx_init(&nlm_global_lock, "nlm_global_lock", NULL, MTX_DEF);
294	TAILQ_INIT(&nlm_waiting_locks);
295	TAILQ_INIT(&nlm_hosts);
296
297	error = syscall_register(&nlm_syscall_offset, &nlm_syscall_sysent,
298	    &nlm_syscall_prev_sysent);
299	if (error)
300		NLM_ERR("Can't register NLM syscall\n");
301	else
302		nlm_syscall_registered = TRUE;
303}
304SYSINIT(nlm_init, SI_SUB_LOCK, SI_ORDER_FIRST, nlm_init, NULL);
305
306static void
307nlm_uninit(void *dummy)
308{
309
310	if (nlm_syscall_registered)
311		syscall_deregister(&nlm_syscall_offset,
312		    &nlm_syscall_prev_sysent);
313}
314SYSUNINIT(nlm_uninit, SI_SUB_LOCK, SI_ORDER_FIRST, nlm_uninit, NULL);
315
316/*
317 * Create a netobj from an arbitrary source.
318 */
319void
320nlm_make_netobj(struct netobj *dst, caddr_t src, size_t srcsize,
321    struct malloc_type *type)
322{
323
324	dst->n_len = srcsize;
325	dst->n_bytes = malloc(srcsize, type, M_WAITOK);
326	memcpy(dst->n_bytes, src, srcsize);
327}
328
329/*
330 * Copy a struct netobj.
331 */
332void
333nlm_copy_netobj(struct netobj *dst, struct netobj *src,
334    struct malloc_type *type)
335{
336
337	nlm_make_netobj(dst, src->n_bytes, src->n_len, type);
338}
339
340
341/*
342 * Create an RPC client handle for the given (address,prog,vers)
343 * triple using UDP.
344 */
345static CLIENT *
346nlm_get_rpc(struct sockaddr *sa, rpcprog_t prog, rpcvers_t vers)
347{
348	char *wchan = "nlmrcv";
349	const char* protofmly;
350	struct sockaddr_storage ss;
351	struct socket *so;
352	CLIENT *rpcb;
353	struct timeval timo;
354	RPCB parms;
355	char *uaddr;
356	enum clnt_stat stat = RPC_SUCCESS;
357	int rpcvers = RPCBVERS4;
358	bool_t do_tcp = FALSE;
359	bool_t tryagain = FALSE;
360	struct portmap mapping;
361	u_short port = 0;
362
363	/*
364	 * First we need to contact the remote RPCBIND service to find
365	 * the right port.
366	 */
367	memcpy(&ss, sa, sa->sa_len);
368	switch (ss.ss_family) {
369	case AF_INET:
370		((struct sockaddr_in *)&ss)->sin_port = htons(111);
371		protofmly = "inet";
372		so = nlm_socket;
373		break;
374
375#ifdef INET6
376	case AF_INET6:
377		((struct sockaddr_in6 *)&ss)->sin6_port = htons(111);
378		protofmly = "inet6";
379		so = nlm_socket6;
380		break;
381#endif
382
383	default:
384		/*
385		 * Unsupported address family - fail.
386		 */
387		return (NULL);
388	}
389
390	rpcb = clnt_dg_create(so, (struct sockaddr *)&ss,
391	    RPCBPROG, rpcvers, 0, 0);
392	if (!rpcb)
393		return (NULL);
394
395try_tcp:
396	parms.r_prog = prog;
397	parms.r_vers = vers;
398	if (do_tcp)
399		parms.r_netid = "tcp";
400	else
401		parms.r_netid = "udp";
402	parms.r_addr = "";
403	parms.r_owner = "";
404
405	/*
406	 * Use the default timeout.
407	 */
408	timo.tv_sec = 25;
409	timo.tv_usec = 0;
410again:
411	switch (rpcvers) {
412	case RPCBVERS4:
413	case RPCBVERS:
414		/*
415		 * Try RPCBIND 4 then 3.
416		 */
417		uaddr = NULL;
418		stat = CLNT_CALL(rpcb, (rpcprog_t) RPCBPROC_GETADDR,
419		    (xdrproc_t) xdr_rpcb, &parms,
420		    (xdrproc_t) xdr_wrapstring, &uaddr, timo);
421		if (stat == RPC_SUCCESS) {
422			/*
423			 * We have a reply from the remote RPCBIND - turn it
424			 * into an appropriate address and make a new client
425			 * that can talk to the remote NLM.
426			 *
427			 * XXX fixup IPv6 scope ID.
428			 */
429			struct netbuf *a;
430			a = __rpc_uaddr2taddr_af(ss.ss_family, uaddr);
431			if (!a) {
432				tryagain = TRUE;
433			} else {
434				tryagain = FALSE;
435				memcpy(&ss, a->buf, a->len);
436				free(a->buf, M_RPC);
437				free(a, M_RPC);
438				xdr_free((xdrproc_t) xdr_wrapstring, &uaddr);
439			}
440		}
441		if (tryagain || stat == RPC_PROGVERSMISMATCH) {
442			if (rpcvers == RPCBVERS4)
443				rpcvers = RPCBVERS;
444			else if (rpcvers == RPCBVERS)
445				rpcvers = PMAPVERS;
446			CLNT_CONTROL(rpcb, CLSET_VERS, &rpcvers);
447			goto again;
448		}
449		break;
450	case PMAPVERS:
451		/*
452		 * Try portmap.
453		 */
454		mapping.pm_prog = parms.r_prog;
455		mapping.pm_vers = parms.r_vers;
456		mapping.pm_prot = do_tcp ? IPPROTO_TCP : IPPROTO_UDP;
457		mapping.pm_port = 0;
458
459		stat = CLNT_CALL(rpcb, (rpcprog_t) PMAPPROC_GETPORT,
460		    (xdrproc_t) xdr_portmap, &mapping,
461		    (xdrproc_t) xdr_u_short, &port, timo);
462
463		if (stat == RPC_SUCCESS) {
464			switch (ss.ss_family) {
465			case AF_INET:
466				((struct sockaddr_in *)&ss)->sin_port =
467					htons(port);
468				break;
469
470#ifdef INET6
471			case AF_INET6:
472				((struct sockaddr_in6 *)&ss)->sin6_port =
473					htons(port);
474				break;
475#endif
476			}
477		}
478		break;
479	default:
480		panic("invalid rpcvers %d", rpcvers);
481	}
482	/*
483	 * We may have a positive response from the portmapper, but the NLM
484	 * service was not found. Make sure we received a valid port.
485	 */
486	switch (ss.ss_family) {
487	case AF_INET:
488		port = ((struct sockaddr_in *)&ss)->sin_port;
489		break;
490#ifdef INET6
491	case AF_INET6:
492		port = ((struct sockaddr_in6 *)&ss)->sin6_port;
493		break;
494#endif
495	}
496	if (stat != RPC_SUCCESS || !port) {
497		/*
498		 * If we were able to talk to rpcbind or portmap, but the udp
499		 * variant wasn't available, ask about tcp.
500		 *
501		 * XXX - We could also check for a TCP portmapper, but
502		 * if the host is running a portmapper at all, we should be able
503		 * to hail it over UDP.
504		 */
505		if (stat == RPC_SUCCESS && !do_tcp) {
506			do_tcp = TRUE;
507			goto try_tcp;
508		}
509
510		/* Otherwise, bad news. */
511		NLM_ERR("NLM: failed to contact remote rpcbind, "
512		    "stat = %d, port = %d\n", (int) stat, port);
513		CLNT_DESTROY(rpcb);
514		return (NULL);
515	}
516
517	if (do_tcp) {
518		/*
519		 * Destroy the UDP client we used to speak to rpcbind and
520		 * recreate as a TCP client.
521		 */
522		struct netconfig *nconf = NULL;
523
524		CLNT_DESTROY(rpcb);
525
526		switch (ss.ss_family) {
527		case AF_INET:
528			nconf = getnetconfigent("tcp");
529			break;
530#ifdef INET6
531		case AF_INET6:
532			nconf = getnetconfigent("tcp6");
533			break;
534#endif
535		}
536
537		rpcb = clnt_reconnect_create(nconf, (struct sockaddr *)&ss,
538		    prog, vers, 0, 0);
539		CLNT_CONTROL(rpcb, CLSET_WAITCHAN, wchan);
540		rpcb->cl_auth = nlm_auth;
541
542	} else {
543		/*
544		 * Re-use the client we used to speak to rpcbind.
545		 */
546		CLNT_CONTROL(rpcb, CLSET_SVC_ADDR, &ss);
547		CLNT_CONTROL(rpcb, CLSET_PROG, &prog);
548		CLNT_CONTROL(rpcb, CLSET_VERS, &vers);
549		CLNT_CONTROL(rpcb, CLSET_WAITCHAN, wchan);
550		rpcb->cl_auth = nlm_auth;
551	}
552
553	return (rpcb);
554}
555
556/*
557 * This async callback after when an async lock request has been
558 * granted. We notify the host which initiated the request.
559 */
560static void
561nlm_lock_callback(void *arg, int pending)
562{
563	struct nlm_async_lock *af = (struct nlm_async_lock *) arg;
564	struct rpc_callextra ext;
565
566	NLM_DEBUG(2, "NLM: async lock %p for %s (sysid %d) granted,"
567	    " cookie %d:%d\n", af, af->af_host->nh_caller_name,
568	    af->af_host->nh_sysid, ng_sysid(&af->af_granted.cookie),
569	    ng_cookie(&af->af_granted.cookie));
570
571	/*
572	 * Send the results back to the host.
573	 *
574	 * Note: there is a possible race here with nlm_host_notify
575	 * destroying the RPC client. To avoid problems, the first
576	 * thing nlm_host_notify does is to cancel pending async lock
577	 * requests.
578	 */
579	memset(&ext, 0, sizeof(ext));
580	ext.rc_auth = nlm_auth;
581	if (af->af_host->nh_vers == NLM_VERS4) {
582		nlm4_granted_msg_4(&af->af_granted,
583		    NULL, af->af_rpc, &ext, nlm_zero_tv);
584	} else {
585		/*
586		 * Back-convert to legacy protocol
587		 */
588		nlm_testargs granted;
589		granted.cookie = af->af_granted.cookie;
590		granted.exclusive = af->af_granted.exclusive;
591		granted.alock.caller_name =
592			af->af_granted.alock.caller_name;
593		granted.alock.fh = af->af_granted.alock.fh;
594		granted.alock.oh = af->af_granted.alock.oh;
595		granted.alock.svid = af->af_granted.alock.svid;
596		granted.alock.l_offset =
597			af->af_granted.alock.l_offset;
598		granted.alock.l_len =
599			af->af_granted.alock.l_len;
600
601		nlm_granted_msg_1(&granted,
602		    NULL, af->af_rpc, &ext, nlm_zero_tv);
603	}
604
605	/*
606	 * Move this entry to the nh_granted list.
607	 */
608	af->af_expiretime = time_uptime + NLM_EXPIRE_TIMEOUT;
609	mtx_lock(&af->af_host->nh_lock);
610	TAILQ_REMOVE(&af->af_host->nh_pending, af, af_link);
611	TAILQ_INSERT_TAIL(&af->af_host->nh_granted, af, af_link);
612	mtx_unlock(&af->af_host->nh_lock);
613}
614
615/*
616 * Free an async lock request. The request must have been removed from
617 * any list.
618 */
619static void
620nlm_free_async_lock(struct nlm_async_lock *af)
621{
622	/*
623	 * Free an async lock.
624	 */
625	if (af->af_rpc)
626		CLNT_RELEASE(af->af_rpc);
627	xdr_free((xdrproc_t) xdr_nlm4_testargs, &af->af_granted);
628	if (af->af_vp)
629		vrele(af->af_vp);
630	free(af, M_NLM);
631}
632
633/*
634 * Cancel our async request - this must be called with
635 * af->nh_host->nh_lock held. This is slightly complicated by a
636 * potential race with our own callback. If we fail to cancel the
637 * lock, it must already have been granted - we make sure our async
638 * task has completed by calling taskqueue_drain in this case.
639 */
640static int
641nlm_cancel_async_lock(struct nlm_async_lock *af)
642{
643	struct nlm_host *host = af->af_host;
644	int error;
645
646	mtx_assert(&host->nh_lock, MA_OWNED);
647
648	mtx_unlock(&host->nh_lock);
649
650	error = VOP_ADVLOCKASYNC(af->af_vp, NULL, F_CANCEL, &af->af_fl,
651	    F_REMOTE, NULL, &af->af_cookie);
652
653	if (error) {
654		/*
655		 * We failed to cancel - make sure our callback has
656		 * completed before we continue.
657		 */
658		taskqueue_drain(taskqueue_thread, &af->af_task);
659	}
660
661	mtx_lock(&host->nh_lock);
662
663	if (!error) {
664		NLM_DEBUG(2, "NLM: async lock %p for %s (sysid %d) "
665		    "cancelled\n", af, host->nh_caller_name, host->nh_sysid);
666
667		/*
668		 * Remove from the nh_pending list and free now that
669		 * we are safe from the callback.
670		 */
671		TAILQ_REMOVE(&host->nh_pending, af, af_link);
672		mtx_unlock(&host->nh_lock);
673		nlm_free_async_lock(af);
674		mtx_lock(&host->nh_lock);
675	}
676
677	return (error);
678}
679
680static void
681nlm_check_expired_locks(struct nlm_host *host)
682{
683	struct nlm_async_lock *af;
684	time_t uptime = time_uptime;
685
686	mtx_lock(&host->nh_lock);
687	while ((af = TAILQ_FIRST(&host->nh_granted)) != NULL
688	    && uptime >= af->af_expiretime) {
689		NLM_DEBUG(2, "NLM: async lock %p for %s (sysid %d) expired,"
690		    " cookie %d:%d\n", af, af->af_host->nh_caller_name,
691		    af->af_host->nh_sysid, ng_sysid(&af->af_granted.cookie),
692		    ng_cookie(&af->af_granted.cookie));
693		TAILQ_REMOVE(&host->nh_granted, af, af_link);
694		mtx_unlock(&host->nh_lock);
695		nlm_free_async_lock(af);
696		mtx_lock(&host->nh_lock);
697	}
698	while ((af = TAILQ_FIRST(&host->nh_finished)) != NULL) {
699		TAILQ_REMOVE(&host->nh_finished, af, af_link);
700		mtx_unlock(&host->nh_lock);
701		nlm_free_async_lock(af);
702		mtx_lock(&host->nh_lock);
703	}
704	mtx_unlock(&host->nh_lock);
705}
706
707/*
708 * Free resources used by a host. This is called after the reference
709 * count has reached zero so it doesn't need to worry about locks.
710 */
711static void
712nlm_host_destroy(struct nlm_host *host)
713{
714
715	mtx_lock(&nlm_global_lock);
716	TAILQ_REMOVE(&nlm_hosts, host, nh_link);
717	mtx_unlock(&nlm_global_lock);
718
719	if (host->nh_srvrpc.nr_client)
720		CLNT_RELEASE(host->nh_srvrpc.nr_client);
721	if (host->nh_clntrpc.nr_client)
722		CLNT_RELEASE(host->nh_clntrpc.nr_client);
723	mtx_destroy(&host->nh_lock);
724	sysctl_ctx_free(&host->nh_sysctl);
725	free(host, M_NLM);
726}
727
728/*
729 * Thread start callback for client lock recovery
730 */
731static void
732nlm_client_recovery_start(void *arg)
733{
734	struct nlm_host *host = (struct nlm_host *) arg;
735
736	NLM_DEBUG(1, "NLM: client lock recovery for %s started\n",
737	    host->nh_caller_name);
738
739	nlm_client_recovery(host);
740
741	NLM_DEBUG(1, "NLM: client lock recovery for %s completed\n",
742	    host->nh_caller_name);
743
744	host->nh_monstate = NLM_MONITORED;
745	nlm_host_release(host);
746
747	kthread_exit();
748}
749
750/*
751 * This is called when we receive a host state change notification. We
752 * unlock any active locks owned by the host. When rpc.lockd is
753 * shutting down, this function is called with newstate set to zero
754 * which allows us to cancel any pending async locks and clear the
755 * locking state.
756 */
757static void
758nlm_host_notify(struct nlm_host *host, int newstate)
759{
760	struct nlm_async_lock *af;
761
762	if (newstate) {
763		NLM_DEBUG(1, "NLM: host %s (sysid %d) rebooted, new "
764		    "state is %d\n", host->nh_caller_name,
765		    host->nh_sysid, newstate);
766	}
767
768	/*
769	 * Cancel any pending async locks for this host.
770	 */
771	mtx_lock(&host->nh_lock);
772	while ((af = TAILQ_FIRST(&host->nh_pending)) != NULL) {
773		/*
774		 * nlm_cancel_async_lock will remove the entry from
775		 * nh_pending and free it.
776		 */
777		nlm_cancel_async_lock(af);
778	}
779	mtx_unlock(&host->nh_lock);
780	nlm_check_expired_locks(host);
781
782	/*
783	 * The host just rebooted - trash its locks.
784	 */
785	lf_clearremotesys(host->nh_sysid);
786	host->nh_state = newstate;
787
788	/*
789	 * If we have any remote locks for this host (i.e. it
790	 * represents a remote NFS server that our local NFS client
791	 * has locks for), start a recovery thread.
792	 */
793	if (newstate != 0
794	    && host->nh_monstate != NLM_RECOVERING
795	    && lf_countlocks(NLM_SYSID_CLIENT | host->nh_sysid) > 0) {
796		struct thread *td;
797		host->nh_monstate = NLM_RECOVERING;
798		refcount_acquire(&host->nh_refs);
799		kthread_add(nlm_client_recovery_start, host, curproc, &td, 0, 0,
800		    "NFS lock recovery for %s", host->nh_caller_name);
801	}
802}
803
804/*
805 * Sysctl handler to count the number of locks for a sysid.
806 */
807static int
808nlm_host_lock_count_sysctl(SYSCTL_HANDLER_ARGS)
809{
810	struct nlm_host *host;
811	int count;
812
813	host = oidp->oid_arg1;
814	count = lf_countlocks(host->nh_sysid);
815	return sysctl_handle_int(oidp, &count, 0, req);
816}
817
818/*
819 * Sysctl handler to count the number of client locks for a sysid.
820 */
821static int
822nlm_host_client_lock_count_sysctl(SYSCTL_HANDLER_ARGS)
823{
824	struct nlm_host *host;
825	int count;
826
827	host = oidp->oid_arg1;
828	count = lf_countlocks(NLM_SYSID_CLIENT | host->nh_sysid);
829	return sysctl_handle_int(oidp, &count, 0, req);
830}
831
832/*
833 * Create a new NLM host.
834 */
835static struct nlm_host *
836nlm_create_host(const char* caller_name)
837{
838	struct nlm_host *host;
839	struct sysctl_oid *oid;
840
841	mtx_assert(&nlm_global_lock, MA_OWNED);
842
843	NLM_DEBUG(1, "NLM: new host %s (sysid %d)\n",
844	    caller_name, nlm_next_sysid);
845	host = malloc(sizeof(struct nlm_host), M_NLM, M_NOWAIT|M_ZERO);
846	if (!host)
847		return (NULL);
848	mtx_init(&host->nh_lock, "nh_lock", NULL, MTX_DEF);
849	host->nh_refs = 1;
850	strlcpy(host->nh_caller_name, caller_name, MAXNAMELEN);
851	host->nh_sysid = nlm_next_sysid++;
852	snprintf(host->nh_sysid_string, sizeof(host->nh_sysid_string),
853		"%d", host->nh_sysid);
854	host->nh_vers = 0;
855	host->nh_state = 0;
856	host->nh_monstate = NLM_UNMONITORED;
857	host->nh_grantcookie = 1;
858	TAILQ_INIT(&host->nh_pending);
859	TAILQ_INIT(&host->nh_granted);
860	TAILQ_INIT(&host->nh_finished);
861	TAILQ_INSERT_TAIL(&nlm_hosts, host, nh_link);
862
863	mtx_unlock(&nlm_global_lock);
864
865	sysctl_ctx_init(&host->nh_sysctl);
866	oid = SYSCTL_ADD_NODE(&host->nh_sysctl,
867	    SYSCTL_STATIC_CHILDREN(_vfs_nlm_sysid),
868	    OID_AUTO, host->nh_sysid_string, CTLFLAG_RD, NULL, "");
869	SYSCTL_ADD_STRING(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
870	    "hostname", CTLFLAG_RD, host->nh_caller_name, 0, "");
871	SYSCTL_ADD_UINT(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
872	    "version", CTLFLAG_RD, &host->nh_vers, 0, "");
873	SYSCTL_ADD_UINT(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
874	    "monitored", CTLFLAG_RD, &host->nh_monstate, 0, "");
875	SYSCTL_ADD_PROC(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
876	    "lock_count", CTLTYPE_INT | CTLFLAG_RD, host, 0,
877	    nlm_host_lock_count_sysctl, "I", "");
878	SYSCTL_ADD_PROC(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
879	    "client_lock_count", CTLTYPE_INT | CTLFLAG_RD, host, 0,
880	    nlm_host_client_lock_count_sysctl, "I", "");
881
882	mtx_lock(&nlm_global_lock);
883
884	return (host);
885}
886
887/*
888 * Acquire the next sysid for remote locks not handled by the NLM.
889 */
890uint32_t
891nlm_acquire_next_sysid(void)
892{
893	uint32_t next_sysid;
894
895	mtx_lock(&nlm_global_lock);
896	next_sysid = nlm_next_sysid++;
897	mtx_unlock(&nlm_global_lock);
898	return (next_sysid);
899}
900
901/*
902 * Return non-zero if the address parts of the two sockaddrs are the
903 * same.
904 */
905static int
906nlm_compare_addr(const struct sockaddr *a, const struct sockaddr *b)
907{
908	const struct sockaddr_in *a4, *b4;
909#ifdef INET6
910	const struct sockaddr_in6 *a6, *b6;
911#endif
912
913	if (a->sa_family != b->sa_family)
914		return (FALSE);
915
916	switch (a->sa_family) {
917	case AF_INET:
918		a4 = (const struct sockaddr_in *) a;
919		b4 = (const struct sockaddr_in *) b;
920		return !memcmp(&a4->sin_addr, &b4->sin_addr,
921		    sizeof(a4->sin_addr));
922#ifdef INET6
923	case AF_INET6:
924		a6 = (const struct sockaddr_in6 *) a;
925		b6 = (const struct sockaddr_in6 *) b;
926		return !memcmp(&a6->sin6_addr, &b6->sin6_addr,
927		    sizeof(a6->sin6_addr));
928#endif
929	}
930
931	return (0);
932}
933
934/*
935 * Check for idle hosts and stop monitoring them. We could also free
936 * the host structure here, possibly after a larger timeout but that
937 * would require some care to avoid races with
938 * e.g. nlm_host_lock_count_sysctl.
939 */
940static void
941nlm_check_idle(void)
942{
943	struct nlm_host *host;
944
945	mtx_assert(&nlm_global_lock, MA_OWNED);
946
947	if (time_uptime <= nlm_next_idle_check)
948		return;
949
950	nlm_next_idle_check = time_uptime + NLM_IDLE_PERIOD;
951
952	TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
953		if (host->nh_monstate == NLM_MONITORED
954		    && time_uptime > host->nh_idle_timeout) {
955			mtx_unlock(&nlm_global_lock);
956			if (lf_countlocks(host->nh_sysid) > 0
957			    || lf_countlocks(NLM_SYSID_CLIENT
958				+ host->nh_sysid)) {
959				host->nh_idle_timeout =
960					time_uptime + NLM_IDLE_TIMEOUT;
961				mtx_lock(&nlm_global_lock);
962				continue;
963			}
964			nlm_host_unmonitor(host);
965			mtx_lock(&nlm_global_lock);
966		}
967	}
968}
969
970/*
971 * Search for an existing NLM host that matches the given name
972 * (typically the caller_name element of an nlm4_lock).  If none is
973 * found, create a new host. If 'addr' is non-NULL, record the remote
974 * address of the host so that we can call it back for async
975 * responses. If 'vers' is greater than zero then record the NLM
976 * program version to use to communicate with this client.
977 */
978struct nlm_host *
979nlm_find_host_by_name(const char *name, const struct sockaddr *addr,
980    rpcvers_t vers)
981{
982	struct nlm_host *host;
983
984	mtx_lock(&nlm_global_lock);
985
986	/*
987	 * The remote host is determined by caller_name.
988	 */
989	TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
990		if (!strcmp(host->nh_caller_name, name))
991			break;
992	}
993
994	if (!host) {
995		host = nlm_create_host(name);
996		if (!host) {
997			mtx_unlock(&nlm_global_lock);
998			return (NULL);
999		}
1000	}
1001	refcount_acquire(&host->nh_refs);
1002
1003	host->nh_idle_timeout = time_uptime + NLM_IDLE_TIMEOUT;
1004
1005	/*
1006	 * If we have an address for the host, record it so that we
1007	 * can send async replies etc.
1008	 */
1009	if (addr) {
1010
1011		KASSERT(addr->sa_len < sizeof(struct sockaddr_storage),
1012		    ("Strange remote transport address length"));
1013
1014		/*
1015		 * If we have seen an address before and we currently
1016		 * have an RPC client handle, make sure the address is
1017		 * the same, otherwise discard the client handle.
1018		 */
1019		if (host->nh_addr.ss_len && host->nh_srvrpc.nr_client) {
1020			if (!nlm_compare_addr(
1021				    (struct sockaddr *) &host->nh_addr,
1022				    addr)
1023			    || host->nh_vers != vers) {
1024				CLIENT *client;
1025				mtx_lock(&host->nh_lock);
1026				client = host->nh_srvrpc.nr_client;
1027				host->nh_srvrpc.nr_client = NULL;
1028				mtx_unlock(&host->nh_lock);
1029				if (client) {
1030					CLNT_RELEASE(client);
1031				}
1032			}
1033		}
1034		memcpy(&host->nh_addr, addr, addr->sa_len);
1035		host->nh_vers = vers;
1036	}
1037
1038	nlm_check_idle();
1039
1040	mtx_unlock(&nlm_global_lock);
1041
1042	return (host);
1043}
1044
1045/*
1046 * Search for an existing NLM host that matches the given remote
1047 * address. If none is found, create a new host with the requested
1048 * address and remember 'vers' as the NLM protocol version to use for
1049 * that host.
1050 */
1051struct nlm_host *
1052nlm_find_host_by_addr(const struct sockaddr *addr, int vers)
1053{
1054	/*
1055	 * Fake up a name using inet_ntop. This buffer is
1056	 * large enough for an IPv6 address.
1057	 */
1058	char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"];
1059	struct nlm_host *host;
1060
1061	switch (addr->sa_family) {
1062	case AF_INET:
1063		inet_ntop(AF_INET,
1064		    &((const struct sockaddr_in *) addr)->sin_addr,
1065		    tmp, sizeof tmp);
1066		break;
1067#ifdef INET6
1068	case AF_INET6:
1069		inet_ntop(AF_INET6,
1070		    &((const struct sockaddr_in6 *) addr)->sin6_addr,
1071		    tmp, sizeof tmp);
1072		break;
1073#endif
1074	default:
1075		strlcpy(tmp, "<unknown>", sizeof(tmp));
1076	}
1077
1078
1079	mtx_lock(&nlm_global_lock);
1080
1081	/*
1082	 * The remote host is determined by caller_name.
1083	 */
1084	TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
1085		if (nlm_compare_addr(addr,
1086			(const struct sockaddr *) &host->nh_addr))
1087			break;
1088	}
1089
1090	if (!host) {
1091		host = nlm_create_host(tmp);
1092		if (!host) {
1093			mtx_unlock(&nlm_global_lock);
1094			return (NULL);
1095		}
1096		memcpy(&host->nh_addr, addr, addr->sa_len);
1097		host->nh_vers = vers;
1098	}
1099	refcount_acquire(&host->nh_refs);
1100
1101	host->nh_idle_timeout = time_uptime + NLM_IDLE_TIMEOUT;
1102
1103	nlm_check_idle();
1104
1105	mtx_unlock(&nlm_global_lock);
1106
1107	return (host);
1108}
1109
1110/*
1111 * Find the NLM host that matches the value of 'sysid'. If none
1112 * exists, return NULL.
1113 */
1114static struct nlm_host *
1115nlm_find_host_by_sysid(int sysid)
1116{
1117	struct nlm_host *host;
1118
1119	TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
1120		if (host->nh_sysid == sysid) {
1121			refcount_acquire(&host->nh_refs);
1122			return (host);
1123		}
1124	}
1125
1126	return (NULL);
1127}
1128
1129void nlm_host_release(struct nlm_host *host)
1130{
1131	if (refcount_release(&host->nh_refs)) {
1132		/*
1133		 * Free the host
1134		 */
1135		nlm_host_destroy(host);
1136	}
1137}
1138
1139/*
1140 * Unregister this NLM host with the local NSM due to idleness.
1141 */
1142static void
1143nlm_host_unmonitor(struct nlm_host *host)
1144{
1145	mon_id smmonid;
1146	sm_stat_res smstat;
1147	struct timeval timo;
1148	enum clnt_stat stat;
1149
1150	NLM_DEBUG(1, "NLM: unmonitoring %s (sysid %d)\n",
1151	    host->nh_caller_name, host->nh_sysid);
1152
1153	/*
1154	 * We put our assigned system ID value in the priv field to
1155	 * make it simpler to find the host if we are notified of a
1156	 * host restart.
1157	 */
1158	smmonid.mon_name = host->nh_caller_name;
1159	smmonid.my_id.my_name = "localhost";
1160	smmonid.my_id.my_prog = NLM_PROG;
1161	smmonid.my_id.my_vers = NLM_SM;
1162	smmonid.my_id.my_proc = NLM_SM_NOTIFY;
1163
1164	timo.tv_sec = 25;
1165	timo.tv_usec = 0;
1166	stat = CLNT_CALL(nlm_nsm, SM_UNMON,
1167	    (xdrproc_t) xdr_mon, &smmonid,
1168	    (xdrproc_t) xdr_sm_stat, &smstat, timo);
1169
1170	if (stat != RPC_SUCCESS) {
1171		NLM_ERR("Failed to contact local NSM - rpc error %d\n", stat);
1172		return;
1173	}
1174	if (smstat.res_stat == stat_fail) {
1175		NLM_ERR("Local NSM refuses to unmonitor %s\n",
1176		    host->nh_caller_name);
1177		return;
1178	}
1179
1180	host->nh_monstate = NLM_UNMONITORED;
1181}
1182
1183/*
1184 * Register this NLM host with the local NSM so that we can be
1185 * notified if it reboots.
1186 */
1187void
1188nlm_host_monitor(struct nlm_host *host, int state)
1189{
1190	mon smmon;
1191	sm_stat_res smstat;
1192	struct timeval timo;
1193	enum clnt_stat stat;
1194
1195	if (state && !host->nh_state) {
1196		/*
1197		 * This is the first time we have seen an NSM state
1198		 * value for this host. We record it here to help
1199		 * detect host reboots.
1200		 */
1201		host->nh_state = state;
1202		NLM_DEBUG(1, "NLM: host %s (sysid %d) has NSM state %d\n",
1203		    host->nh_caller_name, host->nh_sysid, state);
1204	}
1205
1206	mtx_lock(&host->nh_lock);
1207	if (host->nh_monstate != NLM_UNMONITORED) {
1208		mtx_unlock(&host->nh_lock);
1209		return;
1210	}
1211	host->nh_monstate = NLM_MONITORED;
1212	mtx_unlock(&host->nh_lock);
1213
1214	NLM_DEBUG(1, "NLM: monitoring %s (sysid %d)\n",
1215	    host->nh_caller_name, host->nh_sysid);
1216
1217	/*
1218	 * We put our assigned system ID value in the priv field to
1219	 * make it simpler to find the host if we are notified of a
1220	 * host restart.
1221	 */
1222	smmon.mon_id.mon_name = host->nh_caller_name;
1223	smmon.mon_id.my_id.my_name = "localhost";
1224	smmon.mon_id.my_id.my_prog = NLM_PROG;
1225	smmon.mon_id.my_id.my_vers = NLM_SM;
1226	smmon.mon_id.my_id.my_proc = NLM_SM_NOTIFY;
1227	memcpy(smmon.priv, &host->nh_sysid, sizeof(host->nh_sysid));
1228
1229	timo.tv_sec = 25;
1230	timo.tv_usec = 0;
1231	stat = CLNT_CALL(nlm_nsm, SM_MON,
1232	    (xdrproc_t) xdr_mon, &smmon,
1233	    (xdrproc_t) xdr_sm_stat, &smstat, timo);
1234
1235	if (stat != RPC_SUCCESS) {
1236		NLM_ERR("Failed to contact local NSM - rpc error %d\n", stat);
1237		return;
1238	}
1239	if (smstat.res_stat == stat_fail) {
1240		NLM_ERR("Local NSM refuses to monitor %s\n",
1241		    host->nh_caller_name);
1242		mtx_lock(&host->nh_lock);
1243		host->nh_monstate = NLM_MONITOR_FAILED;
1244		mtx_unlock(&host->nh_lock);
1245		return;
1246	}
1247
1248	host->nh_monstate = NLM_MONITORED;
1249}
1250
1251/*
1252 * Return an RPC client handle that can be used to talk to the NLM
1253 * running on the given host.
1254 */
1255CLIENT *
1256nlm_host_get_rpc(struct nlm_host *host, bool_t isserver)
1257{
1258	struct nlm_rpc *rpc;
1259	CLIENT *client;
1260
1261	mtx_lock(&host->nh_lock);
1262
1263	if (isserver)
1264		rpc = &host->nh_srvrpc;
1265	else
1266		rpc = &host->nh_clntrpc;
1267
1268	/*
1269	 * We can't hold onto RPC handles for too long - the async
1270	 * call/reply protocol used by some NLM clients makes it hard
1271	 * to tell when they change port numbers (e.g. after a
1272	 * reboot). Note that if a client reboots while it isn't
1273	 * holding any locks, it won't bother to notify us. We
1274	 * expire the RPC handles after two minutes.
1275	 */
1276	if (rpc->nr_client && time_uptime > rpc->nr_create_time + 2*60) {
1277		client = rpc->nr_client;
1278		rpc->nr_client = NULL;
1279		mtx_unlock(&host->nh_lock);
1280		CLNT_RELEASE(client);
1281		mtx_lock(&host->nh_lock);
1282	}
1283
1284	if (!rpc->nr_client) {
1285		mtx_unlock(&host->nh_lock);
1286		client = nlm_get_rpc((struct sockaddr *)&host->nh_addr,
1287		    NLM_PROG, host->nh_vers);
1288		mtx_lock(&host->nh_lock);
1289
1290		if (client) {
1291			if (rpc->nr_client) {
1292				mtx_unlock(&host->nh_lock);
1293				CLNT_DESTROY(client);
1294				mtx_lock(&host->nh_lock);
1295			} else {
1296				rpc->nr_client = client;
1297				rpc->nr_create_time = time_uptime;
1298			}
1299		}
1300	}
1301
1302	client = rpc->nr_client;
1303	if (client)
1304		CLNT_ACQUIRE(client);
1305	mtx_unlock(&host->nh_lock);
1306
1307	return (client);
1308
1309}
1310
1311int nlm_host_get_sysid(struct nlm_host *host)
1312{
1313
1314	return (host->nh_sysid);
1315}
1316
1317int
1318nlm_host_get_state(struct nlm_host *host)
1319{
1320
1321	return (host->nh_state);
1322}
1323
1324void *
1325nlm_register_wait_lock(struct nlm4_lock *lock, struct vnode *vp)
1326{
1327	struct nlm_waiting_lock *nw;
1328
1329	nw = malloc(sizeof(struct nlm_waiting_lock), M_NLM, M_WAITOK);
1330	nw->nw_lock = *lock;
1331	memcpy(&nw->nw_fh.fh_bytes, nw->nw_lock.fh.n_bytes,
1332	    nw->nw_lock.fh.n_len);
1333	nw->nw_lock.fh.n_bytes = nw->nw_fh.fh_bytes;
1334	nw->nw_waiting = TRUE;
1335	nw->nw_vp = vp;
1336	mtx_lock(&nlm_global_lock);
1337	TAILQ_INSERT_TAIL(&nlm_waiting_locks, nw, nw_link);
1338	mtx_unlock(&nlm_global_lock);
1339
1340	return nw;
1341}
1342
1343void
1344nlm_deregister_wait_lock(void *handle)
1345{
1346	struct nlm_waiting_lock *nw = handle;
1347
1348	mtx_lock(&nlm_global_lock);
1349	TAILQ_REMOVE(&nlm_waiting_locks, nw, nw_link);
1350	mtx_unlock(&nlm_global_lock);
1351
1352	free(nw, M_NLM);
1353}
1354
1355int
1356nlm_wait_lock(void *handle, int timo)
1357{
1358	struct nlm_waiting_lock *nw = handle;
1359	int error;
1360
1361	/*
1362	 * If the granted message arrived before we got here,
1363	 * nw->nw_waiting will be FALSE - in that case, don't sleep.
1364	 */
1365	mtx_lock(&nlm_global_lock);
1366	error = 0;
1367	if (nw->nw_waiting)
1368		error = msleep(nw, &nlm_global_lock, PCATCH, "nlmlock", timo);
1369	TAILQ_REMOVE(&nlm_waiting_locks, nw, nw_link);
1370	if (error) {
1371		/*
1372		 * The granted message may arrive after the
1373		 * interrupt/timeout but before we manage to lock the
1374		 * mutex. Detect this by examining nw_lock.
1375		 */
1376		if (!nw->nw_waiting)
1377			error = 0;
1378	} else {
1379		/*
1380		 * If nlm_cancel_wait is called, then error will be
1381		 * zero but nw_waiting will still be TRUE. We
1382		 * translate this into EINTR.
1383		 */
1384		if (nw->nw_waiting)
1385			error = EINTR;
1386	}
1387	mtx_unlock(&nlm_global_lock);
1388
1389	free(nw, M_NLM);
1390
1391	return (error);
1392}
1393
1394void
1395nlm_cancel_wait(struct vnode *vp)
1396{
1397	struct nlm_waiting_lock *nw;
1398
1399	mtx_lock(&nlm_global_lock);
1400	TAILQ_FOREACH(nw, &nlm_waiting_locks, nw_link) {
1401		if (nw->nw_vp == vp) {
1402			wakeup(nw);
1403		}
1404	}
1405	mtx_unlock(&nlm_global_lock);
1406}
1407
1408
1409/**********************************************************************/
1410
1411/*
1412 * Syscall interface with userland.
1413 */
1414
1415extern void nlm_prog_0(struct svc_req *rqstp, SVCXPRT *transp);
1416extern void nlm_prog_1(struct svc_req *rqstp, SVCXPRT *transp);
1417extern void nlm_prog_3(struct svc_req *rqstp, SVCXPRT *transp);
1418extern void nlm_prog_4(struct svc_req *rqstp, SVCXPRT *transp);
1419
1420static int
1421nlm_register_services(SVCPOOL *pool, int addr_count, char **addrs)
1422{
1423	static rpcvers_t versions[] = {
1424		NLM_SM, NLM_VERS, NLM_VERSX, NLM_VERS4
1425	};
1426	static void (*dispatchers[])(struct svc_req *, SVCXPRT *) = {
1427		nlm_prog_0, nlm_prog_1, nlm_prog_3, nlm_prog_4
1428	};
1429	static const int version_count = sizeof(versions) / sizeof(versions[0]);
1430
1431	SVCXPRT **xprts;
1432	char netid[16];
1433	char uaddr[128];
1434	struct netconfig *nconf;
1435	int i, j, error;
1436
1437	if (!addr_count) {
1438		NLM_ERR("NLM: no service addresses given - can't start server");
1439		return (EINVAL);
1440	}
1441
1442	if (addr_count < 0 || addr_count > 256 ) {
1443		NLM_ERR("NLM:  too many service addresses (%d) given, "
1444		    "max 256 - can't start server\n", addr_count);
1445		return (EINVAL);
1446	}
1447
1448	xprts = malloc(addr_count * sizeof(SVCXPRT *), M_NLM, M_WAITOK|M_ZERO);
1449	for (i = 0; i < version_count; i++) {
1450		for (j = 0; j < addr_count; j++) {
1451			/*
1452			 * Create transports for the first version and
1453			 * then just register everything else to the
1454			 * same transports.
1455			 */
1456			if (i == 0) {
1457				char *up;
1458
1459				error = copyin(&addrs[2*j], &up,
1460				    sizeof(char*));
1461				if (error)
1462					goto out;
1463				error = copyinstr(up, netid, sizeof(netid),
1464				    NULL);
1465				if (error)
1466					goto out;
1467				error = copyin(&addrs[2*j+1], &up,
1468				    sizeof(char*));
1469				if (error)
1470					goto out;
1471				error = copyinstr(up, uaddr, sizeof(uaddr),
1472				    NULL);
1473				if (error)
1474					goto out;
1475				nconf = getnetconfigent(netid);
1476				if (!nconf) {
1477					NLM_ERR("Can't lookup netid %s\n",
1478					    netid);
1479					error = EINVAL;
1480					goto out;
1481				}
1482				xprts[j] = svc_tp_create(pool, dispatchers[i],
1483				    NLM_PROG, versions[i], uaddr, nconf);
1484				if (!xprts[j]) {
1485					NLM_ERR("NLM: unable to create "
1486					    "(NLM_PROG, %d).\n", versions[i]);
1487					error = EINVAL;
1488					goto out;
1489				}
1490				freenetconfigent(nconf);
1491			} else {
1492				nconf = getnetconfigent(xprts[j]->xp_netid);
1493				rpcb_unset(NLM_PROG, versions[i], nconf);
1494				if (!svc_reg(xprts[j], NLM_PROG, versions[i],
1495					dispatchers[i], nconf)) {
1496					NLM_ERR("NLM: can't register "
1497					    "(NLM_PROG, %d)\n", versions[i]);
1498					error = EINVAL;
1499					goto out;
1500				}
1501			}
1502		}
1503	}
1504	error = 0;
1505out:
1506	for (j = 0; j < addr_count; j++) {
1507		if (xprts[j])
1508			SVC_RELEASE(xprts[j]);
1509	}
1510	free(xprts, M_NLM);
1511	return (error);
1512}
1513
1514/*
1515 * Main server entry point. Contacts the local NSM to get its current
1516 * state and send SM_UNMON_ALL. Registers the NLM services and then
1517 * services requests. Does not return until the server is interrupted
1518 * by a signal.
1519 */
1520static int
1521nlm_server_main(int addr_count, char **addrs)
1522{
1523	struct thread *td = curthread;
1524	int error;
1525	SVCPOOL *pool = NULL;
1526	struct sockopt opt;
1527	int portlow;
1528#ifdef INET6
1529	struct sockaddr_in6 sin6;
1530#endif
1531	struct sockaddr_in sin;
1532	my_id id;
1533	sm_stat smstat;
1534	struct timeval timo;
1535	enum clnt_stat stat;
1536	struct nlm_host *host, *nhost;
1537	struct nlm_waiting_lock *nw;
1538	vop_advlock_t *old_nfs_advlock;
1539	vop_reclaim_t *old_nfs_reclaim;
1540
1541	if (nlm_is_running != 0) {
1542		NLM_ERR("NLM: can't start server - "
1543		    "it appears to be running already\n");
1544		return (EPERM);
1545	}
1546
1547	if (nlm_socket == NULL) {
1548		memset(&opt, 0, sizeof(opt));
1549
1550		error = socreate(AF_INET, &nlm_socket, SOCK_DGRAM, 0,
1551		    td->td_ucred, td);
1552		if (error) {
1553			NLM_ERR("NLM: can't create IPv4 socket - error %d\n",
1554			    error);
1555			return (error);
1556		}
1557		opt.sopt_dir = SOPT_SET;
1558		opt.sopt_level = IPPROTO_IP;
1559		opt.sopt_name = IP_PORTRANGE;
1560		portlow = IP_PORTRANGE_LOW;
1561		opt.sopt_val = &portlow;
1562		opt.sopt_valsize = sizeof(portlow);
1563		sosetopt(nlm_socket, &opt);
1564
1565#ifdef INET6
1566		nlm_socket6 = NULL;
1567		error = socreate(AF_INET6, &nlm_socket6, SOCK_DGRAM, 0,
1568		    td->td_ucred, td);
1569		if (error) {
1570			NLM_ERR("NLM: can't create IPv6 socket - error %d\n",
1571			    error);
1572			soclose(nlm_socket);
1573			nlm_socket = NULL;
1574			return (error);
1575		}
1576		opt.sopt_dir = SOPT_SET;
1577		opt.sopt_level = IPPROTO_IPV6;
1578		opt.sopt_name = IPV6_PORTRANGE;
1579		portlow = IPV6_PORTRANGE_LOW;
1580		opt.sopt_val = &portlow;
1581		opt.sopt_valsize = sizeof(portlow);
1582		sosetopt(nlm_socket6, &opt);
1583#endif
1584	}
1585
1586	nlm_auth = authunix_create(curthread->td_ucred);
1587
1588#ifdef INET6
1589	memset(&sin6, 0, sizeof(sin6));
1590	sin6.sin6_len = sizeof(sin6);
1591	sin6.sin6_family = AF_INET6;
1592	sin6.sin6_addr = in6addr_loopback;
1593	nlm_nsm = nlm_get_rpc((struct sockaddr *) &sin6, SM_PROG, SM_VERS);
1594	if (!nlm_nsm) {
1595#endif
1596		memset(&sin, 0, sizeof(sin));
1597		sin.sin_len = sizeof(sin);
1598		sin.sin_family = AF_INET;
1599		sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
1600		nlm_nsm = nlm_get_rpc((struct sockaddr *) &sin, SM_PROG,
1601		    SM_VERS);
1602#ifdef INET6
1603	}
1604#endif
1605
1606	if (!nlm_nsm) {
1607		NLM_ERR("Can't start NLM - unable to contact NSM\n");
1608		error = EINVAL;
1609		goto out;
1610	}
1611
1612	pool = svcpool_create("NLM", NULL);
1613
1614	error = nlm_register_services(pool, addr_count, addrs);
1615	if (error)
1616		goto out;
1617
1618	memset(&id, 0, sizeof(id));
1619	id.my_name = "NFS NLM";
1620
1621	timo.tv_sec = 25;
1622	timo.tv_usec = 0;
1623	stat = CLNT_CALL(nlm_nsm, SM_UNMON_ALL,
1624	    (xdrproc_t) xdr_my_id, &id,
1625	    (xdrproc_t) xdr_sm_stat, &smstat, timo);
1626
1627	if (stat != RPC_SUCCESS) {
1628		struct rpc_err err;
1629
1630		CLNT_GETERR(nlm_nsm, &err);
1631		NLM_ERR("NLM: unexpected error contacting NSM, "
1632		    "stat=%d, errno=%d\n", stat, err.re_errno);
1633		error = EINVAL;
1634		goto out;
1635	}
1636	nlm_is_running = 1;
1637
1638	NLM_DEBUG(1, "NLM: local NSM state is %d\n", smstat.state);
1639	nlm_nsm_state = smstat.state;
1640
1641	old_nfs_advlock = nfs_advlock_p;
1642	nfs_advlock_p = nlm_advlock;
1643	old_nfs_reclaim = nfs_reclaim_p;
1644	nfs_reclaim_p = nlm_reclaim;
1645
1646	svc_run(pool);
1647	error = 0;
1648
1649	nfs_advlock_p = old_nfs_advlock;
1650	nfs_reclaim_p = old_nfs_reclaim;
1651
1652out:
1653	nlm_is_running = 0;
1654	if (pool)
1655		svcpool_destroy(pool);
1656
1657	/*
1658	 * We are finished communicating with the NSM.
1659	 */
1660	if (nlm_nsm) {
1661		CLNT_RELEASE(nlm_nsm);
1662		nlm_nsm = NULL;
1663	}
1664
1665	/*
1666	 * Trash all the existing state so that if the server
1667	 * restarts, it gets a clean slate. This is complicated by the
1668	 * possibility that there may be other threads trying to make
1669	 * client locking requests.
1670	 *
1671	 * First we fake a client reboot notification which will
1672	 * cancel any pending async locks and purge remote lock state
1673	 * from the local lock manager. We release the reference from
1674	 * nlm_hosts to the host (which may remove it from the list
1675	 * and free it). After this phase, the only entries in the
1676	 * nlm_host list should be from other threads performing
1677	 * client lock requests.
1678	 */
1679	mtx_lock(&nlm_global_lock);
1680	TAILQ_FOREACH(nw, &nlm_waiting_locks, nw_link) {
1681		wakeup(nw);
1682	}
1683	TAILQ_FOREACH_SAFE(host, &nlm_hosts, nh_link, nhost) {
1684		mtx_unlock(&nlm_global_lock);
1685		nlm_host_notify(host, 0);
1686		nlm_host_release(host);
1687		mtx_lock(&nlm_global_lock);
1688	}
1689	mtx_unlock(&nlm_global_lock);
1690
1691	AUTH_DESTROY(nlm_auth);
1692
1693	return (error);
1694}
1695
1696int
1697sys_nlm_syscall(struct thread *td, struct nlm_syscall_args *uap)
1698{
1699	int error;
1700
1701#if __FreeBSD_version >= 700000
1702	error = priv_check(td, PRIV_NFS_LOCKD);
1703#else
1704	error = suser(td);
1705#endif
1706	if (error)
1707		return (error);
1708
1709	nlm_debug_level = uap->debug_level;
1710	nlm_grace_threshold = time_uptime + uap->grace_period;
1711	nlm_next_idle_check = time_uptime + NLM_IDLE_PERIOD;
1712
1713	return nlm_server_main(uap->addr_count, uap->addrs);
1714}
1715
1716/**********************************************************************/
1717
1718/*
1719 * NLM implementation details, called from the RPC stubs.
1720 */
1721
1722
1723void
1724nlm_sm_notify(struct nlm_sm_status *argp)
1725{
1726	uint32_t sysid;
1727	struct nlm_host *host;
1728
1729	NLM_DEBUG(3, "nlm_sm_notify(): mon_name = %s\n", argp->mon_name);
1730	memcpy(&sysid, &argp->priv, sizeof(sysid));
1731	host = nlm_find_host_by_sysid(sysid);
1732	if (host) {
1733		nlm_host_notify(host, argp->state);
1734		nlm_host_release(host);
1735	}
1736}
1737
1738static void
1739nlm_convert_to_fhandle_t(fhandle_t *fhp, struct netobj *p)
1740{
1741	memcpy(fhp, p->n_bytes, sizeof(fhandle_t));
1742}
1743
1744struct vfs_state {
1745	struct mount	*vs_mp;
1746	struct vnode	*vs_vp;
1747	int		vs_vnlocked;
1748};
1749
1750static int
1751nlm_get_vfs_state(struct nlm_host *host, struct svc_req *rqstp,
1752    fhandle_t *fhp, struct vfs_state *vs, accmode_t accmode)
1753{
1754	int error, exflags;
1755	struct ucred *cred = NULL, *credanon = NULL;
1756
1757	memset(vs, 0, sizeof(*vs));
1758
1759	vs->vs_mp = vfs_getvfs(&fhp->fh_fsid);
1760	if (!vs->vs_mp) {
1761		return (ESTALE);
1762	}
1763
1764	/* accmode == 0 means don't check, since it is an unlock. */
1765	if (accmode != 0) {
1766		error = VFS_CHECKEXP(vs->vs_mp,
1767		    (struct sockaddr *)&host->nh_addr, &exflags, &credanon,
1768		    NULL, NULL);
1769		if (error)
1770			goto out;
1771
1772		if (exflags & MNT_EXRDONLY ||
1773		    (vs->vs_mp->mnt_flag & MNT_RDONLY)) {
1774			error = EROFS;
1775			goto out;
1776		}
1777	}
1778
1779	error = VFS_FHTOVP(vs->vs_mp, &fhp->fh_fid, LK_EXCLUSIVE, &vs->vs_vp);
1780	if (error)
1781		goto out;
1782	vs->vs_vnlocked = TRUE;
1783
1784	if (accmode != 0) {
1785		if (!svc_getcred(rqstp, &cred, NULL)) {
1786			error = EINVAL;
1787			goto out;
1788		}
1789		if (cred->cr_uid == 0 || (exflags & MNT_EXPORTANON)) {
1790			crfree(cred);
1791			cred = credanon;
1792			credanon = NULL;
1793		}
1794
1795		/*
1796		 * Check cred.
1797		 */
1798		error = VOP_ACCESS(vs->vs_vp, accmode, cred, curthread);
1799		/*
1800		 * If this failed and accmode != VWRITE, try again with
1801		 * VWRITE to maintain backwards compatibility with the
1802		 * old code that always used VWRITE.
1803		 */
1804		if (error != 0 && accmode != VWRITE)
1805			error = VOP_ACCESS(vs->vs_vp, VWRITE, cred, curthread);
1806		if (error)
1807			goto out;
1808	}
1809
1810#if __FreeBSD_version < 800011
1811	VOP_UNLOCK(vs->vs_vp, 0, curthread);
1812#else
1813	VOP_UNLOCK(vs->vs_vp, 0);
1814#endif
1815	vs->vs_vnlocked = FALSE;
1816
1817out:
1818	if (cred)
1819		crfree(cred);
1820	if (credanon)
1821		crfree(credanon);
1822
1823	return (error);
1824}
1825
1826static void
1827nlm_release_vfs_state(struct vfs_state *vs)
1828{
1829
1830	if (vs->vs_vp) {
1831		if (vs->vs_vnlocked)
1832			vput(vs->vs_vp);
1833		else
1834			vrele(vs->vs_vp);
1835	}
1836	if (vs->vs_mp)
1837		vfs_rel(vs->vs_mp);
1838}
1839
1840static nlm4_stats
1841nlm_convert_error(int error)
1842{
1843
1844	if (error == ESTALE)
1845		return nlm4_stale_fh;
1846	else if (error == EROFS)
1847		return nlm4_rofs;
1848	else
1849		return nlm4_failed;
1850}
1851
1852int
1853nlm_do_test(nlm4_testargs *argp, nlm4_testres *result, struct svc_req *rqstp,
1854	CLIENT **rpcp)
1855{
1856	fhandle_t fh;
1857	struct vfs_state vs;
1858	struct nlm_host *host, *bhost;
1859	int error, sysid;
1860	struct flock fl;
1861	accmode_t accmode;
1862
1863	memset(result, 0, sizeof(*result));
1864	memset(&vs, 0, sizeof(vs));
1865
1866	host = nlm_find_host_by_name(argp->alock.caller_name,
1867	    svc_getrpccaller(rqstp), rqstp->rq_vers);
1868	if (!host) {
1869		result->stat.stat = nlm4_denied_nolocks;
1870		return (ENOMEM);
1871	}
1872
1873	NLM_DEBUG(3, "nlm_do_test(): caller_name = %s (sysid = %d)\n",
1874	    host->nh_caller_name, host->nh_sysid);
1875
1876	nlm_check_expired_locks(host);
1877	sysid = host->nh_sysid;
1878
1879	nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
1880	nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
1881
1882	if (time_uptime < nlm_grace_threshold) {
1883		result->stat.stat = nlm4_denied_grace_period;
1884		goto out;
1885	}
1886
1887	accmode = argp->exclusive ? VWRITE : VREAD;
1888	error = nlm_get_vfs_state(host, rqstp, &fh, &vs, accmode);
1889	if (error) {
1890		result->stat.stat = nlm_convert_error(error);
1891		goto out;
1892	}
1893
1894	fl.l_start = argp->alock.l_offset;
1895	fl.l_len = argp->alock.l_len;
1896	fl.l_pid = argp->alock.svid;
1897	fl.l_sysid = sysid;
1898	fl.l_whence = SEEK_SET;
1899	if (argp->exclusive)
1900		fl.l_type = F_WRLCK;
1901	else
1902		fl.l_type = F_RDLCK;
1903	error = VOP_ADVLOCK(vs.vs_vp, NULL, F_GETLK, &fl, F_REMOTE);
1904	if (error) {
1905		result->stat.stat = nlm4_failed;
1906		goto out;
1907	}
1908
1909	if (fl.l_type == F_UNLCK) {
1910		result->stat.stat = nlm4_granted;
1911	} else {
1912		result->stat.stat = nlm4_denied;
1913		result->stat.nlm4_testrply_u.holder.exclusive =
1914			(fl.l_type == F_WRLCK);
1915		result->stat.nlm4_testrply_u.holder.svid = fl.l_pid;
1916		bhost = nlm_find_host_by_sysid(fl.l_sysid);
1917		if (bhost) {
1918			/*
1919			 * We don't have any useful way of recording
1920			 * the value of oh used in the original lock
1921			 * request. Ideally, the test reply would have
1922			 * a space for the owning host's name allowing
1923			 * our caller's NLM to keep track.
1924			 *
1925			 * As far as I can see, Solaris uses an eight
1926			 * byte structure for oh which contains a four
1927			 * byte pid encoded in local byte order and
1928			 * the first four bytes of the host
1929			 * name. Linux uses a variable length string
1930			 * 'pid@hostname' in ascii but doesn't even
1931			 * return that in test replies.
1932			 *
1933			 * For the moment, return nothing in oh
1934			 * (already zero'ed above).
1935			 */
1936			nlm_host_release(bhost);
1937		}
1938		result->stat.nlm4_testrply_u.holder.l_offset = fl.l_start;
1939		result->stat.nlm4_testrply_u.holder.l_len = fl.l_len;
1940	}
1941
1942out:
1943	nlm_release_vfs_state(&vs);
1944	if (rpcp)
1945		*rpcp = nlm_host_get_rpc(host, TRUE);
1946	nlm_host_release(host);
1947	return (0);
1948}
1949
1950int
1951nlm_do_lock(nlm4_lockargs *argp, nlm4_res *result, struct svc_req *rqstp,
1952    bool_t monitor, CLIENT **rpcp)
1953{
1954	fhandle_t fh;
1955	struct vfs_state vs;
1956	struct nlm_host *host;
1957	int error, sysid;
1958	struct flock fl;
1959	accmode_t accmode;
1960
1961	memset(result, 0, sizeof(*result));
1962	memset(&vs, 0, sizeof(vs));
1963
1964	host = nlm_find_host_by_name(argp->alock.caller_name,
1965	    svc_getrpccaller(rqstp), rqstp->rq_vers);
1966	if (!host) {
1967		result->stat.stat = nlm4_denied_nolocks;
1968		return (ENOMEM);
1969	}
1970
1971	NLM_DEBUG(3, "nlm_do_lock(): caller_name = %s (sysid = %d)\n",
1972	    host->nh_caller_name, host->nh_sysid);
1973
1974	if (monitor && host->nh_state && argp->state
1975	    && host->nh_state != argp->state) {
1976		/*
1977		 * The host rebooted without telling us. Trash its
1978		 * locks.
1979		 */
1980		nlm_host_notify(host, argp->state);
1981	}
1982
1983	nlm_check_expired_locks(host);
1984	sysid = host->nh_sysid;
1985
1986	nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
1987	nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
1988
1989	if (time_uptime < nlm_grace_threshold && !argp->reclaim) {
1990		result->stat.stat = nlm4_denied_grace_period;
1991		goto out;
1992	}
1993
1994	accmode = argp->exclusive ? VWRITE : VREAD;
1995	error = nlm_get_vfs_state(host, rqstp, &fh, &vs, accmode);
1996	if (error) {
1997		result->stat.stat = nlm_convert_error(error);
1998		goto out;
1999	}
2000
2001	fl.l_start = argp->alock.l_offset;
2002	fl.l_len = argp->alock.l_len;
2003	fl.l_pid = argp->alock.svid;
2004	fl.l_sysid = sysid;
2005	fl.l_whence = SEEK_SET;
2006	if (argp->exclusive)
2007		fl.l_type = F_WRLCK;
2008	else
2009		fl.l_type = F_RDLCK;
2010	if (argp->block) {
2011		struct nlm_async_lock *af;
2012		CLIENT *client;
2013		struct nlm_grantcookie cookie;
2014
2015		/*
2016		 * First, make sure we can contact the host's NLM.
2017		 */
2018		client = nlm_host_get_rpc(host, TRUE);
2019		if (!client) {
2020			result->stat.stat = nlm4_failed;
2021			goto out;
2022		}
2023
2024		/*
2025		 * First we need to check and see if there is an
2026		 * existing blocked lock that matches. This could be a
2027		 * badly behaved client or an RPC re-send. If we find
2028		 * one, just return nlm4_blocked.
2029		 */
2030		mtx_lock(&host->nh_lock);
2031		TAILQ_FOREACH(af, &host->nh_pending, af_link) {
2032			if (af->af_fl.l_start == fl.l_start
2033			    && af->af_fl.l_len == fl.l_len
2034			    && af->af_fl.l_pid == fl.l_pid
2035			    && af->af_fl.l_type == fl.l_type) {
2036				break;
2037			}
2038		}
2039		if (!af) {
2040			cookie.ng_sysid = host->nh_sysid;
2041			cookie.ng_cookie = host->nh_grantcookie++;
2042		}
2043		mtx_unlock(&host->nh_lock);
2044		if (af) {
2045			CLNT_RELEASE(client);
2046			result->stat.stat = nlm4_blocked;
2047			goto out;
2048		}
2049
2050		af = malloc(sizeof(struct nlm_async_lock), M_NLM,
2051		    M_WAITOK|M_ZERO);
2052		TASK_INIT(&af->af_task, 0, nlm_lock_callback, af);
2053		af->af_vp = vs.vs_vp;
2054		af->af_fl = fl;
2055		af->af_host = host;
2056		af->af_rpc = client;
2057		/*
2058		 * We use M_RPC here so that we can xdr_free the thing
2059		 * later.
2060		 */
2061		nlm_make_netobj(&af->af_granted.cookie,
2062		    (caddr_t)&cookie, sizeof(cookie), M_RPC);
2063		af->af_granted.exclusive = argp->exclusive;
2064		af->af_granted.alock.caller_name =
2065			strdup(argp->alock.caller_name, M_RPC);
2066		nlm_copy_netobj(&af->af_granted.alock.fh,
2067		    &argp->alock.fh, M_RPC);
2068		nlm_copy_netobj(&af->af_granted.alock.oh,
2069		    &argp->alock.oh, M_RPC);
2070		af->af_granted.alock.svid = argp->alock.svid;
2071		af->af_granted.alock.l_offset = argp->alock.l_offset;
2072		af->af_granted.alock.l_len = argp->alock.l_len;
2073
2074		/*
2075		 * Put the entry on the pending list before calling
2076		 * VOP_ADVLOCKASYNC. We do this in case the lock
2077		 * request was blocked (returning EINPROGRESS) but
2078		 * then granted before we manage to run again. The
2079		 * client may receive the granted message before we
2080		 * send our blocked reply but thats their problem.
2081		 */
2082		mtx_lock(&host->nh_lock);
2083		TAILQ_INSERT_TAIL(&host->nh_pending, af, af_link);
2084		mtx_unlock(&host->nh_lock);
2085
2086		error = VOP_ADVLOCKASYNC(vs.vs_vp, NULL, F_SETLK, &fl, F_REMOTE,
2087		    &af->af_task, &af->af_cookie);
2088
2089		/*
2090		 * If the lock completed synchronously, just free the
2091		 * tracking structure now.
2092		 */
2093		if (error != EINPROGRESS) {
2094			CLNT_RELEASE(af->af_rpc);
2095			mtx_lock(&host->nh_lock);
2096			TAILQ_REMOVE(&host->nh_pending, af, af_link);
2097			mtx_unlock(&host->nh_lock);
2098			xdr_free((xdrproc_t) xdr_nlm4_testargs,
2099			    &af->af_granted);
2100			free(af, M_NLM);
2101		} else {
2102			NLM_DEBUG(2, "NLM: pending async lock %p for %s "
2103			    "(sysid %d)\n", af, host->nh_caller_name, sysid);
2104			/*
2105			 * Don't vrele the vnode just yet - this must
2106			 * wait until either the async callback
2107			 * happens or the lock is cancelled.
2108			 */
2109			vs.vs_vp = NULL;
2110		}
2111	} else {
2112		error = VOP_ADVLOCK(vs.vs_vp, NULL, F_SETLK, &fl, F_REMOTE);
2113	}
2114
2115	if (error) {
2116		if (error == EINPROGRESS) {
2117			result->stat.stat = nlm4_blocked;
2118		} else if (error == EDEADLK) {
2119			result->stat.stat = nlm4_deadlck;
2120		} else if (error == EAGAIN) {
2121			result->stat.stat = nlm4_denied;
2122		} else {
2123			result->stat.stat = nlm4_failed;
2124		}
2125	} else {
2126		if (monitor)
2127			nlm_host_monitor(host, argp->state);
2128		result->stat.stat = nlm4_granted;
2129	}
2130
2131out:
2132	nlm_release_vfs_state(&vs);
2133	if (rpcp)
2134		*rpcp = nlm_host_get_rpc(host, TRUE);
2135	nlm_host_release(host);
2136	return (0);
2137}
2138
2139int
2140nlm_do_cancel(nlm4_cancargs *argp, nlm4_res *result, struct svc_req *rqstp,
2141    CLIENT **rpcp)
2142{
2143	fhandle_t fh;
2144	struct vfs_state vs;
2145	struct nlm_host *host;
2146	int error, sysid;
2147	struct flock fl;
2148	struct nlm_async_lock *af;
2149
2150	memset(result, 0, sizeof(*result));
2151	memset(&vs, 0, sizeof(vs));
2152
2153	host = nlm_find_host_by_name(argp->alock.caller_name,
2154	    svc_getrpccaller(rqstp), rqstp->rq_vers);
2155	if (!host) {
2156		result->stat.stat = nlm4_denied_nolocks;
2157		return (ENOMEM);
2158	}
2159
2160	NLM_DEBUG(3, "nlm_do_cancel(): caller_name = %s (sysid = %d)\n",
2161	    host->nh_caller_name, host->nh_sysid);
2162
2163	nlm_check_expired_locks(host);
2164	sysid = host->nh_sysid;
2165
2166	nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
2167	nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
2168
2169	if (time_uptime < nlm_grace_threshold) {
2170		result->stat.stat = nlm4_denied_grace_period;
2171		goto out;
2172	}
2173
2174	error = nlm_get_vfs_state(host, rqstp, &fh, &vs, (accmode_t)0);
2175	if (error) {
2176		result->stat.stat = nlm_convert_error(error);
2177		goto out;
2178	}
2179
2180	fl.l_start = argp->alock.l_offset;
2181	fl.l_len = argp->alock.l_len;
2182	fl.l_pid = argp->alock.svid;
2183	fl.l_sysid = sysid;
2184	fl.l_whence = SEEK_SET;
2185	if (argp->exclusive)
2186		fl.l_type = F_WRLCK;
2187	else
2188		fl.l_type = F_RDLCK;
2189
2190	/*
2191	 * First we need to try and find the async lock request - if
2192	 * there isn't one, we give up and return nlm4_denied.
2193	 */
2194	mtx_lock(&host->nh_lock);
2195
2196	TAILQ_FOREACH(af, &host->nh_pending, af_link) {
2197		if (af->af_fl.l_start == fl.l_start
2198		    && af->af_fl.l_len == fl.l_len
2199		    && af->af_fl.l_pid == fl.l_pid
2200		    && af->af_fl.l_type == fl.l_type) {
2201			break;
2202		}
2203	}
2204
2205	if (!af) {
2206		mtx_unlock(&host->nh_lock);
2207		result->stat.stat = nlm4_denied;
2208		goto out;
2209	}
2210
2211	error = nlm_cancel_async_lock(af);
2212
2213	if (error) {
2214		result->stat.stat = nlm4_denied;
2215	} else {
2216		result->stat.stat = nlm4_granted;
2217	}
2218
2219	mtx_unlock(&host->nh_lock);
2220
2221out:
2222	nlm_release_vfs_state(&vs);
2223	if (rpcp)
2224		*rpcp = nlm_host_get_rpc(host, TRUE);
2225	nlm_host_release(host);
2226	return (0);
2227}
2228
2229int
2230nlm_do_unlock(nlm4_unlockargs *argp, nlm4_res *result, struct svc_req *rqstp,
2231    CLIENT **rpcp)
2232{
2233	fhandle_t fh;
2234	struct vfs_state vs;
2235	struct nlm_host *host;
2236	int error, sysid;
2237	struct flock fl;
2238
2239	memset(result, 0, sizeof(*result));
2240	memset(&vs, 0, sizeof(vs));
2241
2242	host = nlm_find_host_by_name(argp->alock.caller_name,
2243	    svc_getrpccaller(rqstp), rqstp->rq_vers);
2244	if (!host) {
2245		result->stat.stat = nlm4_denied_nolocks;
2246		return (ENOMEM);
2247	}
2248
2249	NLM_DEBUG(3, "nlm_do_unlock(): caller_name = %s (sysid = %d)\n",
2250	    host->nh_caller_name, host->nh_sysid);
2251
2252	nlm_check_expired_locks(host);
2253	sysid = host->nh_sysid;
2254
2255	nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
2256	nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
2257
2258	if (time_uptime < nlm_grace_threshold) {
2259		result->stat.stat = nlm4_denied_grace_period;
2260		goto out;
2261	}
2262
2263	error = nlm_get_vfs_state(host, rqstp, &fh, &vs, (accmode_t)0);
2264	if (error) {
2265		result->stat.stat = nlm_convert_error(error);
2266		goto out;
2267	}
2268
2269	fl.l_start = argp->alock.l_offset;
2270	fl.l_len = argp->alock.l_len;
2271	fl.l_pid = argp->alock.svid;
2272	fl.l_sysid = sysid;
2273	fl.l_whence = SEEK_SET;
2274	fl.l_type = F_UNLCK;
2275	error = VOP_ADVLOCK(vs.vs_vp, NULL, F_UNLCK, &fl, F_REMOTE);
2276
2277	/*
2278	 * Ignore the error - there is no result code for failure,
2279	 * only for grace period.
2280	 */
2281	result->stat.stat = nlm4_granted;
2282
2283out:
2284	nlm_release_vfs_state(&vs);
2285	if (rpcp)
2286		*rpcp = nlm_host_get_rpc(host, TRUE);
2287	nlm_host_release(host);
2288	return (0);
2289}
2290
2291int
2292nlm_do_granted(nlm4_testargs *argp, nlm4_res *result, struct svc_req *rqstp,
2293
2294    CLIENT **rpcp)
2295{
2296	struct nlm_host *host;
2297	struct nlm_waiting_lock *nw;
2298
2299	memset(result, 0, sizeof(*result));
2300
2301	host = nlm_find_host_by_addr(svc_getrpccaller(rqstp), rqstp->rq_vers);
2302	if (!host) {
2303		result->stat.stat = nlm4_denied_nolocks;
2304		return (ENOMEM);
2305	}
2306
2307	nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
2308	result->stat.stat = nlm4_denied;
2309	KFAIL_POINT_CODE(DEBUG_FP, nlm_deny_grant, goto out);
2310
2311	mtx_lock(&nlm_global_lock);
2312	TAILQ_FOREACH(nw, &nlm_waiting_locks, nw_link) {
2313		if (!nw->nw_waiting)
2314			continue;
2315		if (argp->alock.svid == nw->nw_lock.svid
2316		    && argp->alock.l_offset == nw->nw_lock.l_offset
2317		    && argp->alock.l_len == nw->nw_lock.l_len
2318		    && argp->alock.fh.n_len == nw->nw_lock.fh.n_len
2319		    && !memcmp(argp->alock.fh.n_bytes, nw->nw_lock.fh.n_bytes,
2320			nw->nw_lock.fh.n_len)) {
2321			nw->nw_waiting = FALSE;
2322			wakeup(nw);
2323			result->stat.stat = nlm4_granted;
2324			break;
2325		}
2326	}
2327	mtx_unlock(&nlm_global_lock);
2328
2329out:
2330	if (rpcp)
2331		*rpcp = nlm_host_get_rpc(host, TRUE);
2332	nlm_host_release(host);
2333	return (0);
2334}
2335
2336void
2337nlm_do_granted_res(nlm4_res *argp, struct svc_req *rqstp)
2338{
2339	struct nlm_host *host = NULL;
2340	struct nlm_async_lock *af = NULL;
2341	int error;
2342
2343	if (argp->cookie.n_len != sizeof(struct nlm_grantcookie)) {
2344		NLM_DEBUG(1, "NLM: bogus grant cookie");
2345		goto out;
2346	}
2347
2348	host = nlm_find_host_by_sysid(ng_sysid(&argp->cookie));
2349	if (!host) {
2350		NLM_DEBUG(1, "NLM: Unknown host rejected our grant");
2351		goto out;
2352	}
2353
2354	mtx_lock(&host->nh_lock);
2355	TAILQ_FOREACH(af, &host->nh_granted, af_link)
2356	    if (ng_cookie(&argp->cookie) ==
2357		ng_cookie(&af->af_granted.cookie))
2358		    break;
2359	if (af)
2360		TAILQ_REMOVE(&host->nh_granted, af, af_link);
2361	mtx_unlock(&host->nh_lock);
2362
2363	if (!af) {
2364		NLM_DEBUG(1, "NLM: host %s (sysid %d) replied to our grant "
2365		    "with unrecognized cookie %d:%d", host->nh_caller_name,
2366		    host->nh_sysid, ng_sysid(&argp->cookie),
2367		    ng_cookie(&argp->cookie));
2368		goto out;
2369	}
2370
2371	if (argp->stat.stat != nlm4_granted) {
2372		af->af_fl.l_type = F_UNLCK;
2373		error = VOP_ADVLOCK(af->af_vp, NULL, F_UNLCK, &af->af_fl, F_REMOTE);
2374		if (error) {
2375			NLM_DEBUG(1, "NLM: host %s (sysid %d) rejected our grant "
2376			    "and we failed to unlock (%d)", host->nh_caller_name,
2377			    host->nh_sysid, error);
2378			goto out;
2379		}
2380
2381		NLM_DEBUG(5, "NLM: async lock %p rejected by host %s (sysid %d)",
2382		    af, host->nh_caller_name, host->nh_sysid);
2383	} else {
2384		NLM_DEBUG(5, "NLM: async lock %p accepted by host %s (sysid %d)",
2385		    af, host->nh_caller_name, host->nh_sysid);
2386	}
2387
2388 out:
2389	if (af)
2390		nlm_free_async_lock(af);
2391	if (host)
2392		nlm_host_release(host);
2393}
2394
2395void
2396nlm_do_free_all(nlm4_notify *argp)
2397{
2398	struct nlm_host *host, *thost;
2399
2400	TAILQ_FOREACH_SAFE(host, &nlm_hosts, nh_link, thost) {
2401		if (!strcmp(host->nh_caller_name, argp->name))
2402			nlm_host_notify(host, argp->state);
2403	}
2404}
2405
2406/*
2407 * Kernel module glue
2408 */
2409static int
2410nfslockd_modevent(module_t mod, int type, void *data)
2411{
2412
2413	switch (type) {
2414	case MOD_LOAD:
2415		return (0);
2416	case MOD_UNLOAD:
2417		/* The NLM module cannot be safely unloaded. */
2418		/* FALLTHROUGH */
2419	default:
2420		return (EOPNOTSUPP);
2421	}
2422}
2423static moduledata_t nfslockd_mod = {
2424	"nfslockd",
2425	nfslockd_modevent,
2426	NULL,
2427};
2428DECLARE_MODULE(nfslockd, nfslockd_mod, SI_SUB_VFS, SI_ORDER_ANY);
2429
2430/* So that loader and kldload(2) can find us, wherever we are.. */
2431MODULE_DEPEND(nfslockd, krpc, 1, 1, 1);
2432MODULE_DEPEND(nfslockd, nfslock, 1, 1, 1);
2433MODULE_VERSION(nfslockd, 1);
2434