xref: /illumos-gate/usr/src/uts/common/rpc/clnt_clts.c (revision 445f2479fe3d7435daab18bf2cdc310b86cd6738)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T
29  * All Rights Reserved
30  */
31 
32 /*
33  * Portions of this source code were derived from Berkeley 4.3 BSD
34  * under license from the Regents of the University of California.
35  */
36 
37 #pragma ident	"%Z%%M%	%I%	%E% SMI"
38 
39 /*
40  * Implements a kernel based, client side RPC.
41  */
42 
43 #include <sys/param.h>
44 #include <sys/types.h>
45 #include <sys/systm.h>
46 #include <sys/sysmacros.h>
47 #include <sys/stream.h>
48 #include <sys/strsubr.h>
49 #include <sys/ddi.h>
50 #include <sys/tiuser.h>
51 #include <sys/tihdr.h>
52 #include <sys/t_kuser.h>
53 #include <sys/errno.h>
54 #include <sys/kmem.h>
55 #include <sys/debug.h>
56 #include <sys/kstat.h>
57 #include <sys/t_lock.h>
58 #include <sys/cmn_err.h>
59 #include <sys/conf.h>
60 #include <sys/disp.h>
61 #include <sys/taskq.h>
62 #include <sys/list.h>
63 #include <sys/atomic.h>
64 #include <sys/zone.h>
65 #include <netinet/in.h>
66 #include <rpc/types.h>
67 #include <rpc/xdr.h>
68 #include <rpc/auth.h>
69 #include <rpc/clnt.h>
70 #include <rpc/rpc_msg.h>
71 
72 static enum clnt_stat clnt_clts_kcallit(CLIENT *, rpcproc_t, xdrproc_t,
73 		    caddr_t, xdrproc_t, caddr_t, struct timeval);
74 static void	clnt_clts_kabort(CLIENT *);
75 static void	clnt_clts_kerror(CLIENT *, struct rpc_err *);
76 static bool_t	clnt_clts_kfreeres(CLIENT *, xdrproc_t, caddr_t);
77 static bool_t	clnt_clts_kcontrol(CLIENT *, int, char *);
78 static void	clnt_clts_kdestroy(CLIENT *);
79 static int	clnt_clts_ksettimers(CLIENT *, struct rpc_timers *,
80 		    struct rpc_timers *, int, void (*)(), caddr_t, uint32_t);
81 
82 /*
83  * Operations vector for CLTS based RPC
84  */
85 static struct clnt_ops clts_ops = {
86 	clnt_clts_kcallit,	/* do rpc call */
87 	clnt_clts_kabort,	/* abort call */
88 	clnt_clts_kerror,	/* return error status */
89 	clnt_clts_kfreeres,	/* free results */
90 	clnt_clts_kdestroy,	/* destroy rpc handle */
91 	clnt_clts_kcontrol,	/* the ioctl() of rpc */
92 	clnt_clts_ksettimers	/* set retry timers */
93 };
94 
95 /*
96  * Endpoint for CLTS (INET, INET6, loopback, etc.)
97  */
98 typedef struct endpnt_type {
99 	struct endpnt_type *e_next;	/* pointer to next endpoint type */
100 	list_t		e_pool;		/* list of available endpoints */
101 	list_t		e_ilist;	/* list of idle endpints */
102 	struct endpnt	*e_pcurr;	/* pointer to current endpoint */
103 	char		e_protofmly[KNC_STRSIZE];	/* protocol family */
104 	dev_t		e_rdev;		/* device */
105 	kmutex_t	e_plock;	/* pool lock */
106 	kmutex_t	e_ilock;	/* idle list lock */
107 	timeout_id_t	e_itimer;	/* timer to dispatch the taskq */
108 	uint_t		e_cnt;		/* number of endpoints in the pool */
109 	zoneid_t	e_zoneid;	/* zoneid of endpoint type */
110 	kcondvar_t	e_async_cv;	/* cv for asynchronous reap threads */
111 	uint_t		e_async_count;	/* count of asynchronous reap threads */
112 } endpnt_type_t;
113 
114 typedef struct endpnt {
115 	list_node_t	e_node;		/* link to the pool */
116 	list_node_t	e_idle;		/* link to the idle list */
117 	endpnt_type_t	*e_type;	/* back pointer to endpoint type */
118 	TIUSER		*e_tiptr;	/* pointer to transport endpoint */
119 	queue_t		*e_wq;		/* write queue */
120 	uint_t		e_flags;	/* endpoint flags */
121 	uint_t		e_ref;		/* ref count on endpoint */
122 	kcondvar_t	e_cv;		/* condition variable */
123 	kmutex_t	e_lock;		/* protects cv and flags */
124 	time_t		e_itime;	/* time when rele'd */
125 } endpnt_t;
126 
127 #define	ENDPNT_ESTABLISHED	0x1	/* endpoint is established */
128 #define	ENDPNT_WAITING		0x2	/* thread waiting for endpoint */
129 #define	ENDPNT_BOUND		0x4	/* endpoint is bound */
130 #define	ENDPNT_STALE		0x8	/* endpoint is dead */
131 #define	ENDPNT_ONIDLE		0x10	/* endpoint is on the idle list */
132 
133 static krwlock_t	endpnt_type_lock; /* protects endpnt_type_list */
134 static endpnt_type_t	*endpnt_type_list = NULL; /* list of CLTS endpoints */
135 static struct kmem_cache	*endpnt_cache; /* cache of endpnt_t's */
136 static taskq_t			*endpnt_taskq; /* endpnt_t reaper thread */
137 static bool_t			taskq_created; /* flag for endpnt_taskq */
138 static kmutex_t			endpnt_taskq_lock; /* taskq lock */
139 static zone_key_t		endpnt_destructor_key;
140 
141 #define	DEFAULT_ENDPOINT_REAP_INTERVAL 60 /* 1 minute */
142 #define	DEFAULT_INTERVAL_SHIFT 30 /* 30 seconds */
143 
144 /*
145  * Endpoint tunables
146  */
147 static int	clnt_clts_max_endpoints = -1;
148 static int	clnt_clts_hash_size = DEFAULT_HASH_SIZE;
149 static time_t	clnt_clts_endpoint_reap_interval = -1;
150 static clock_t	clnt_clts_taskq_dispatch_interval;
151 
152 /*
153  * Response completion hash queue
154  */
155 static call_table_t *clts_call_ht;
156 
157 /*
158  * Routines for the endpoint manager
159  */
160 static struct endpnt_type *endpnt_type_create(struct knetconfig *);
161 static void endpnt_type_free(struct endpnt_type *);
162 static int check_endpnt(struct endpnt *, struct endpnt **);
163 static struct endpnt *endpnt_get(struct knetconfig *, int);
164 static void endpnt_rele(struct endpnt *);
165 static void endpnt_reap_settimer(endpnt_type_t *);
166 static void endpnt_reap(endpnt_type_t *);
167 static void endpnt_reap_dispatch(void *);
168 static void endpnt_reclaim(zoneid_t);
169 
170 
171 /*
172  * Request dipatching function.
173  */
174 static int clnt_clts_dispatch_send(queue_t *q, mblk_t *, struct netbuf *addr,
175 					calllist_t *, uint_t);
176 
177 /*
178  * The size of the preserialized RPC header information.
179  */
180 #define	CKU_HDRSIZE	20
181 /*
182  * The initial allocation size.  It is small to reduce space requirements.
183  */
184 #define	CKU_INITSIZE	2048
185 /*
186  * The size of additional allocations, if required.  It is larger to
187  * reduce the number of actual allocations.
188  */
189 #define	CKU_ALLOCSIZE	8192
190 
191 /*
192  * Private data per rpc handle.  This structure is allocated by
193  * clnt_clts_kcreate, and freed by clnt_clts_kdestroy.
194  */
195 struct cku_private {
196 	CLIENT			 cku_client;	/* client handle */
197 	int			 cku_retrys;	/* request retrys */
198 	calllist_t		 cku_call;
199 	struct endpnt		*cku_endpnt;	/* open end point */
200 	struct knetconfig	 cku_config;
201 	struct netbuf		 cku_addr;	/* remote address */
202 	struct rpc_err		 cku_err;	/* error status */
203 	XDR			 cku_outxdr;	/* xdr stream for output */
204 	XDR			 cku_inxdr;	/* xdr stream for input */
205 	char			 cku_rpchdr[CKU_HDRSIZE + 4]; /* rpc header */
206 	struct cred		*cku_cred;	/* credentials */
207 	struct rpc_timers	*cku_timers;	/* for estimating RTT */
208 	struct rpc_timers	*cku_timeall;	/* for estimating RTT */
209 	void			 (*cku_feedback)(int, int, caddr_t);
210 						/* ptr to feedback rtn */
211 	caddr_t			 cku_feedarg;	/* argument for feedback func */
212 	uint32_t		 cku_xid;	/* current XID */
213 	bool_t			 cku_bcast;	/* RPC broadcast hint */
214 	int			cku_useresvport; /* Use reserved port */
215 	struct rpc_clts_client	*cku_stats;	/* counters for the zone */
216 };
217 
218 static const struct rpc_clts_client {
219 	kstat_named_t	rccalls;
220 	kstat_named_t	rcbadcalls;
221 	kstat_named_t	rcretrans;
222 	kstat_named_t	rcbadxids;
223 	kstat_named_t	rctimeouts;
224 	kstat_named_t	rcnewcreds;
225 	kstat_named_t	rcbadverfs;
226 	kstat_named_t	rctimers;
227 	kstat_named_t	rcnomem;
228 	kstat_named_t	rccantsend;
229 } clts_rcstat_tmpl = {
230 	{ "calls",	KSTAT_DATA_UINT64 },
231 	{ "badcalls",	KSTAT_DATA_UINT64 },
232 	{ "retrans",	KSTAT_DATA_UINT64 },
233 	{ "badxids",	KSTAT_DATA_UINT64 },
234 	{ "timeouts",	KSTAT_DATA_UINT64 },
235 	{ "newcreds",	KSTAT_DATA_UINT64 },
236 	{ "badverfs",	KSTAT_DATA_UINT64 },
237 	{ "timers",	KSTAT_DATA_UINT64 },
238 	{ "nomem",	KSTAT_DATA_UINT64 },
239 	{ "cantsend",	KSTAT_DATA_UINT64 },
240 };
241 
242 static uint_t clts_rcstat_ndata =
243 	sizeof (clts_rcstat_tmpl) / sizeof (kstat_named_t);
244 
245 #define	RCSTAT_INCR(s, x)			\
246 	atomic_add_64(&(s)->x.value.ui64, 1)
247 
248 #define	ptoh(p)		(&((p)->cku_client))
249 #define	htop(h)		((struct cku_private *)((h)->cl_private))
250 
251 /*
252  * Times to retry
253  */
254 #define	SNDTRIES	4
255 #define	REFRESHES	2	/* authentication refreshes */
256 
257 /*
258  * The following is used to determine the global default behavior for
259  * CLTS when binding to a local port.
260  *
261  * If the value is set to 1 the default will be to select a reserved
262  * (aka privileged) port, if the value is zero the default will be to
263  * use non-reserved ports.  Users of kRPC may override this by using
264  * CLNT_CONTROL() and CLSET_BINDRESVPORT.
265  */
266 static int clnt_clts_do_bindresvport = 1;
267 
268 #define	BINDRESVPORT_RETRIES 5
269 
270 void
271 clnt_clts_stats_init(zoneid_t zoneid, struct rpc_clts_client **statsp)
272 {
273 	kstat_t *ksp;
274 	kstat_named_t *knp;
275 
276 	knp = rpcstat_zone_init_common(zoneid, "unix", "rpc_clts_client",
277 	    (const kstat_named_t *)&clts_rcstat_tmpl,
278 	    sizeof (clts_rcstat_tmpl));
279 	/*
280 	 * Backwards compatibility for old kstat clients
281 	 */
282 	ksp = kstat_create_zone("unix", 0, "rpc_client", "rpc",
283 	    KSTAT_TYPE_NAMED, clts_rcstat_ndata,
284 	    KSTAT_FLAG_VIRTUAL | KSTAT_FLAG_WRITABLE, zoneid);
285 	if (ksp) {
286 		ksp->ks_data = knp;
287 		kstat_install(ksp);
288 	}
289 	*statsp = (struct rpc_clts_client *)knp;
290 }
291 
292 void
293 clnt_clts_stats_fini(zoneid_t zoneid, struct rpc_clts_client **statsp)
294 {
295 	rpcstat_zone_fini_common(zoneid, "unix", "rpc_clts_client");
296 	kstat_delete_byname_zone("unix", 0, "rpc_client", zoneid);
297 	kmem_free(*statsp, sizeof (clts_rcstat_tmpl));
298 }
299 
300 /*
301  * Create an rpc handle for a clts rpc connection.
302  * Allocates space for the handle structure and the private data.
303  */
304 /* ARGSUSED */
305 int
306 clnt_clts_kcreate(struct knetconfig *config, struct netbuf *addr,
307 	rpcprog_t pgm, rpcvers_t vers, int retrys, struct cred *cred,
308 	CLIENT **cl)
309 {
310 	CLIENT *h;
311 	struct cku_private *p;
312 	struct rpc_msg call_msg;
313 	int error;
314 	int plen;
315 
316 	if (cl == NULL)
317 		return (EINVAL);
318 
319 	*cl = NULL;
320 	error = 0;
321 
322 	p = kmem_zalloc(sizeof (*p), KM_SLEEP);
323 
324 	h = ptoh(p);
325 
326 	/* handle */
327 	h->cl_ops = &clts_ops;
328 	h->cl_private = (caddr_t)p;
329 	h->cl_auth = authkern_create();
330 
331 	/* call message, just used to pre-serialize below */
332 	call_msg.rm_xid = 0;
333 	call_msg.rm_direction = CALL;
334 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
335 	call_msg.rm_call.cb_prog = pgm;
336 	call_msg.rm_call.cb_vers = vers;
337 
338 	/* private */
339 	clnt_clts_kinit(h, addr, retrys, cred);
340 
341 	xdrmem_create(&p->cku_outxdr, p->cku_rpchdr, CKU_HDRSIZE, XDR_ENCODE);
342 
343 	/* pre-serialize call message header */
344 	if (!xdr_callhdr(&p->cku_outxdr, &call_msg)) {
345 		error = EINVAL;		/* XXX */
346 		goto bad;
347 	}
348 
349 	p->cku_config.knc_rdev = config->knc_rdev;
350 	p->cku_config.knc_semantics = config->knc_semantics;
351 	plen = strlen(config->knc_protofmly) + 1;
352 	p->cku_config.knc_protofmly = kmem_alloc(plen, KM_SLEEP);
353 	bcopy(config->knc_protofmly, p->cku_config.knc_protofmly, plen);
354 	p->cku_useresvport = -1; /* value is has not been set */
355 
356 	cv_init(&p->cku_call.call_cv, NULL, CV_DEFAULT, NULL);
357 	mutex_init(&p->cku_call.call_lock, NULL, MUTEX_DEFAULT, NULL);
358 
359 	*cl = h;
360 	return (0);
361 
362 bad:
363 	auth_destroy(h->cl_auth);
364 	kmem_free(p->cku_addr.buf, addr->maxlen);
365 	kmem_free(p, sizeof (struct cku_private));
366 
367 	return (error);
368 }
369 
370 void
371 clnt_clts_kinit(CLIENT *h, struct netbuf *addr, int retrys, cred_t *cred)
372 {
373 	/* LINTED pointer alignment */
374 	struct cku_private *p = htop(h);
375 	struct rpcstat *rsp;
376 
377 	rsp = zone_getspecific(rpcstat_zone_key, rpc_zone());
378 	ASSERT(rsp != NULL);
379 
380 	p->cku_retrys = retrys;
381 
382 	if (p->cku_addr.maxlen < addr->len) {
383 		if (p->cku_addr.maxlen != 0 && p->cku_addr.buf != NULL)
384 			kmem_free(p->cku_addr.buf, p->cku_addr.maxlen);
385 
386 		p->cku_addr.buf = kmem_zalloc(addr->maxlen, KM_SLEEP);
387 		p->cku_addr.maxlen = addr->maxlen;
388 	}
389 
390 	p->cku_addr.len = addr->len;
391 	bcopy(addr->buf, p->cku_addr.buf, addr->len);
392 
393 	p->cku_cred = cred;
394 	p->cku_xid = 0;
395 	p->cku_timers = NULL;
396 	p->cku_timeall = NULL;
397 	p->cku_feedback = NULL;
398 	p->cku_bcast = FALSE;
399 	p->cku_call.call_xid = 0;
400 	p->cku_call.call_hash = 0;
401 	p->cku_call.call_notified = FALSE;
402 	p->cku_call.call_next = NULL;
403 	p->cku_call.call_prev = NULL;
404 	p->cku_call.call_reply = NULL;
405 	p->cku_call.call_wq = NULL;
406 	p->cku_stats = rsp->rpc_clts_client;
407 }
408 
409 /*
410  * set the timers.  Return current retransmission timeout.
411  */
412 static int
413 clnt_clts_ksettimers(CLIENT *h, struct rpc_timers *t, struct rpc_timers *all,
414 	int minimum, void (*feedback)(int, int, caddr_t), caddr_t arg,
415 	uint32_t xid)
416 {
417 	/* LINTED pointer alignment */
418 	struct cku_private *p = htop(h);
419 	int value;
420 
421 	p->cku_feedback = feedback;
422 	p->cku_feedarg = arg;
423 	p->cku_timers = t;
424 	p->cku_timeall = all;
425 	if (xid)
426 		p->cku_xid = xid;
427 	value = all->rt_rtxcur;
428 	value += t->rt_rtxcur;
429 	if (value < minimum)
430 		return (minimum);
431 	RCSTAT_INCR(p->cku_stats, rctimers);
432 	return (value);
433 }
434 
435 /*
436  * Time out back off function. tim is in HZ
437  */
438 #define	MAXTIMO	(20 * hz)
439 #define	backoff(tim)	(((tim) < MAXTIMO) ? dobackoff(tim) : (tim))
440 #define	dobackoff(tim)	((((tim) << 1) > MAXTIMO) ? MAXTIMO : ((tim) << 1))
441 
442 #define	RETRY_POLL_TIMO	30
443 
444 /*
445  * Call remote procedure.
446  * Most of the work of rpc is done here.  We serialize what is left
447  * of the header (some was pre-serialized in the handle), serialize
448  * the arguments, and send it off.  We wait for a reply or a time out.
449  * Timeout causes an immediate return, other packet problems may cause
450  * a retry on the receive.  When a good packet is received we deserialize
451  * it, and check verification.  A bad reply code will cause one retry
452  * with full (longhand) credentials.
453  */
454 enum clnt_stat
455 clnt_clts_kcallit_addr(CLIENT *h, rpcproc_t procnum, xdrproc_t xdr_args,
456 	caddr_t argsp, xdrproc_t xdr_results, caddr_t resultsp,
457 	struct timeval wait, struct netbuf *sin)
458 {
459 	/* LINTED pointer alignment */
460 	struct cku_private *p = htop(h);
461 	XDR *xdrs;
462 	int stries = p->cku_retrys;
463 	int refreshes = REFRESHES;	/* number of times to refresh cred */
464 	int round_trip;			/* time the RPC */
465 	int error;
466 	int hdrsz;
467 	mblk_t *mp;
468 	mblk_t *mpdup;
469 	mblk_t *resp = NULL;
470 	mblk_t *tmp;
471 	calllist_t *call = &p->cku_call;
472 	clock_t timout = 0;
473 	bool_t interrupted;
474 	enum clnt_stat status;
475 	struct rpc_msg reply_msg;
476 	enum clnt_stat re_status;
477 	endpnt_t *endpt;
478 
479 	RCSTAT_INCR(p->cku_stats, rccalls);
480 
481 	RPCLOG(2, "clnt_clts_kcallit_addr: wait.tv_sec: %ld\n", wait.tv_sec);
482 	RPCLOG(2, "clnt_clts_kcallit_addr: wait.tv_usec: %ld\n", wait.tv_usec);
483 
484 	timout = TIMEVAL_TO_TICK(&wait);
485 
486 	if (p->cku_xid == 0) {
487 		p->cku_xid = alloc_xid();
488 		if (p->cku_endpnt != NULL)
489 			endpnt_rele(p->cku_endpnt);
490 		p->cku_endpnt = NULL;
491 	}
492 
493 	mpdup = NULL;
494 call_again:
495 
496 	if (mpdup == NULL) {
497 
498 		while ((mp = allocb(CKU_INITSIZE, BPRI_LO)) == NULL) {
499 			if (strwaitbuf(CKU_INITSIZE, BPRI_LO)) {
500 				p->cku_err.re_status = RPC_SYSTEMERROR;
501 				p->cku_err.re_errno = ENOSR;
502 				goto done;
503 			}
504 		}
505 
506 		xdrs = &p->cku_outxdr;
507 		xdrmblk_init(xdrs, mp, XDR_ENCODE, CKU_ALLOCSIZE);
508 
509 		if (h->cl_auth->ah_cred.oa_flavor != RPCSEC_GSS) {
510 			/*
511 			 * Copy in the preserialized RPC header
512 			 * information.
513 			 */
514 			bcopy(p->cku_rpchdr, mp->b_rptr, CKU_HDRSIZE);
515 
516 			/*
517 			 * transaction id is the 1st thing in the output
518 			 * buffer.
519 			 */
520 			/* LINTED pointer alignment */
521 			(*(uint32_t *)(mp->b_rptr)) = p->cku_xid;
522 
523 			/* Skip the preserialized stuff. */
524 			XDR_SETPOS(xdrs, CKU_HDRSIZE);
525 
526 			/* Serialize dynamic stuff into the output buffer. */
527 			if ((!XDR_PUTINT32(xdrs, (int32_t *)&procnum)) ||
528 			    (!AUTH_MARSHALL(h->cl_auth, xdrs, p->cku_cred)) ||
529 			    (!(*xdr_args)(xdrs, argsp))) {
530 				freemsg(mp);
531 				p->cku_err.re_status = RPC_CANTENCODEARGS;
532 				p->cku_err.re_errno = EIO;
533 				goto done;
534 			}
535 		} else {
536 			uint32_t *uproc = (uint32_t *)
537 			    &p->cku_rpchdr[CKU_HDRSIZE];
538 			IXDR_PUT_U_INT32(uproc, procnum);
539 
540 			(*(uint32_t *)(&p->cku_rpchdr[0])) = p->cku_xid;
541 			XDR_SETPOS(xdrs, 0);
542 
543 			/* Serialize the procedure number and the arguments. */
544 			if (!AUTH_WRAP(h->cl_auth, (caddr_t)p->cku_rpchdr,
545 			    CKU_HDRSIZE+4, xdrs, xdr_args, argsp)) {
546 				freemsg(mp);
547 				p->cku_err.re_status = RPC_CANTENCODEARGS;
548 				p->cku_err.re_errno = EIO;
549 				goto done;
550 			}
551 		}
552 	} else
553 		mp = mpdup;
554 
555 	mpdup = dupmsg(mp);
556 	if (mpdup == NULL) {
557 		freemsg(mp);
558 		p->cku_err.re_status = RPC_SYSTEMERROR;
559 		p->cku_err.re_errno = ENOSR;
560 		goto done;
561 	}
562 
563 	/*
564 	 * Grab an endpnt only if the endpoint is NULL.  We could be retrying
565 	 * the request and in this case we want to go through the same
566 	 * source port, so that the duplicate request cache may detect a
567 	 * retry.
568 	 */
569 
570 	if (p->cku_endpnt == NULL)
571 		p->cku_endpnt = endpnt_get(&p->cku_config, p->cku_useresvport);
572 
573 	if (p->cku_endpnt == NULL) {
574 		freemsg(mp);
575 		p->cku_err.re_status = RPC_SYSTEMERROR;
576 		p->cku_err.re_errno = ENOSR;
577 		goto done;
578 	}
579 
580 	round_trip = lbolt;
581 
582 	error = clnt_clts_dispatch_send(p->cku_endpnt->e_wq, mp,
583 					&p->cku_addr, call, p->cku_xid);
584 
585 	if (error != 0) {
586 		freemsg(mp);
587 		p->cku_err.re_status = RPC_CANTSEND;
588 		p->cku_err.re_errno = error;
589 		RCSTAT_INCR(p->cku_stats, rccantsend);
590 		goto done1;
591 	}
592 
593 	RPCLOG(64, "clnt_clts_kcallit_addr: sent call for xid 0x%x\n",
594 		p->cku_xid);
595 
596 	/*
597 	 * There are two reasons for which we go back to to tryread.
598 	 *
599 	 * a) In case the status is RPC_PROCUNAVAIL and we sent out a
600 	 *    broadcast we should not get any invalid messages with the
601 	 *    RPC_PROCUNAVAIL error back. Some broken RPC implementations
602 	 *    send them and for this we have to ignore them ( as we would
603 	 *    have never received them ) and look for another message
604 	 *    which might contain the valid response because we don't know
605 	 *    how many broken implementations are in the network. So we are
606 	 *    going to loop until
607 	 *    - we received a valid response
608 	 *    - we have processed all invalid responses and
609 	 *	got a time out when we try to receive again a
610 	 *	message.
611 	 *
612 	 * b) We will jump back to tryread also in case we failed
613 	 *    within the AUTH_VALIDATE. In this case we should move
614 	 *    on and loop until we received a valid response or we
615 	 *    have processed all responses with broken authentication
616 	 *    and we got a time out when we try to receive a message.
617 	 */
618 tryread:
619 	mutex_enter(&call->call_lock);
620 	interrupted = FALSE;
621 	if (call->call_notified == FALSE) {
622 		klwp_t *lwp = ttolwp(curthread);
623 		clock_t cv_wait_ret = 1; /* init to > 0 */
624 		clock_t cv_timout = timout;
625 
626 		if (lwp != NULL)
627 			lwp->lwp_nostop++;
628 
629 		cv_timout += lbolt;
630 
631 		if (h->cl_nosignal)
632 			while ((cv_wait_ret =
633 				cv_timedwait(&call->call_cv,
634 				&call->call_lock, cv_timout)) > 0 &&
635 				call->call_notified == FALSE);
636 		else
637 			while ((cv_wait_ret =
638 				cv_timedwait_sig(&call->call_cv,
639 				&call->call_lock, cv_timout)) > 0 &&
640 				call->call_notified == FALSE);
641 
642 		if (cv_wait_ret == 0)
643 			interrupted = TRUE;
644 
645 		if (lwp != NULL)
646 			lwp->lwp_nostop--;
647 	}
648 	resp = call->call_reply;
649 	call->call_reply = NULL;
650 	status = call->call_status;
651 	/*
652 	 * We have to reset the call_notified here. In case we have
653 	 * to do a retry ( e.g. in case we got a RPC_PROCUNAVAIL
654 	 * error ) we need to set this to false to ensure that
655 	 * we will wait for the next message. When the next message
656 	 * is going to arrive the function clnt_clts_dispatch_notify
657 	 * will set this to true again.
658 	 */
659 	call->call_notified = FALSE;
660 	mutex_exit(&call->call_lock);
661 
662 	if (status == RPC_TIMEDOUT) {
663 		if (interrupted) {
664 			/*
665 			 * We got interrupted, bail out
666 			 */
667 			p->cku_err.re_status = RPC_INTR;
668 			p->cku_err.re_errno = EINTR;
669 			goto done1;
670 		} else {
671 			/*
672 			 * It's possible that our response arrived
673 			 * right after we timed out.  Check to see
674 			 * if it has arrived before we remove the
675 			 * calllist from the dispatch queue.
676 			 */
677 			mutex_enter(&call->call_lock);
678 			if (call->call_notified == TRUE) {
679 				resp = call->call_reply;
680 				call->call_reply = NULL;
681 				mutex_exit(&call->call_lock);
682 				RPCLOG(8, "clnt_clts_kcallit_addr: "
683 				"response received for request "
684 				"w/xid 0x%x after timeout\n",
685 				p->cku_xid);
686 				goto getresponse;
687 			}
688 			mutex_exit(&call->call_lock);
689 
690 			RPCLOG(8, "clnt_clts_kcallit_addr: "
691 				"request w/xid 0x%x timedout "
692 				"waiting for reply\n", p->cku_xid);
693 #if 0 /* XXX not yet */
694 			/*
695 			 * Timeout may be due to a dead gateway. Send
696 			 * an ioctl downstream advising deletion of
697 			 * route when we reach the half-way point to
698 			 * timing out.
699 			 */
700 			if (stries == p->cku_retrys/2) {
701 				t_kadvise(p->cku_endpnt->e_tiptr,
702 					(uchar_t *)p->cku_addr.buf,
703 					p->cku_addr.len);
704 			}
705 #endif /* not yet */
706 			p->cku_err.re_status = RPC_TIMEDOUT;
707 			p->cku_err.re_errno = ETIMEDOUT;
708 			RCSTAT_INCR(p->cku_stats, rctimeouts);
709 			goto done1;
710 		}
711 	}
712 
713 getresponse:
714 	/*
715 	 * Check to see if a response arrived.  If it one is
716 	 * present then proceed to process the reponse.  Otherwise
717 	 * fall through to retry or retransmit the request.  This
718 	 * is probably not the optimal thing to do, but since we
719 	 * are most likely dealing with a unrealiable transport it
720 	 * is the safe thing to so.
721 	 */
722 	if (resp == NULL) {
723 		p->cku_err.re_status = RPC_CANTRECV;
724 		p->cku_err.re_errno = EIO;
725 		goto done1;
726 	}
727 
728 	/*
729 	 * Prepare the message for further processing.  We need to remove
730 	 * the datagram header and copy the source address if necessary.  No
731 	 * need to verify the header since rpcmod took care of that.
732 	 */
733 	/*
734 	 * Copy the source address if the caller has supplied a netbuf.
735 	 */
736 	if (sin != NULL) {
737 		union T_primitives *pptr;
738 
739 		pptr = (union T_primitives *)resp->b_rptr;
740 		bcopy(resp->b_rptr + pptr->unitdata_ind.SRC_offset, sin->buf,
741 			pptr->unitdata_ind.SRC_length);
742 		sin->len = pptr->unitdata_ind.SRC_length;
743 	}
744 
745 	/*
746 	 * Pop off the datagram header.
747 	 */
748 	hdrsz = resp->b_wptr - resp->b_rptr;
749 	if ((resp->b_wptr - (resp->b_rptr + hdrsz)) == 0) {
750 		tmp = resp;
751 		resp = resp->b_cont;
752 		tmp->b_cont = NULL;
753 		freeb(tmp);
754 	} else {
755 		unsigned char *ud_off = resp->b_rptr;
756 		resp->b_rptr += hdrsz;
757 		tmp = dupb(resp);
758 		if (tmp == NULL) {
759 			p->cku_err.re_status = RPC_SYSTEMERROR;
760 			p->cku_err.re_errno = ENOSR;
761 			freemsg(resp);
762 			goto done1;
763 		}
764 		tmp->b_cont = resp->b_cont;
765 		resp->b_rptr = ud_off;
766 		freeb(resp);
767 		resp = tmp;
768 	}
769 
770 	round_trip = lbolt - round_trip;
771 	/*
772 	 * Van Jacobson timer algorithm here, only if NOT a retransmission.
773 	 */
774 	if (p->cku_timers != NULL && stries == p->cku_retrys) {
775 		int rt;
776 
777 		rt = round_trip;
778 		rt -= (p->cku_timers->rt_srtt >> 3);
779 		p->cku_timers->rt_srtt += rt;
780 		if (rt < 0)
781 			rt = - rt;
782 		rt -= (p->cku_timers->rt_deviate >> 2);
783 		p->cku_timers->rt_deviate += rt;
784 		p->cku_timers->rt_rtxcur =
785 		    (clock_t)((p->cku_timers->rt_srtt >> 2) +
786 		    p->cku_timers->rt_deviate) >> 1;
787 
788 		rt = round_trip;
789 		rt -= (p->cku_timeall->rt_srtt >> 3);
790 		p->cku_timeall->rt_srtt += rt;
791 		if (rt < 0)
792 			rt = - rt;
793 		rt -= (p->cku_timeall->rt_deviate >> 2);
794 		p->cku_timeall->rt_deviate += rt;
795 		p->cku_timeall->rt_rtxcur =
796 		    (clock_t)((p->cku_timeall->rt_srtt >> 2) +
797 		    p->cku_timeall->rt_deviate) >> 1;
798 		if (p->cku_feedback != NULL) {
799 			(*p->cku_feedback)(FEEDBACK_OK, procnum,
800 			    p->cku_feedarg);
801 		}
802 	}
803 
804 	/*
805 	 * Process reply
806 	 */
807 	xdrs = &(p->cku_inxdr);
808 	xdrmblk_init(xdrs, resp, XDR_DECODE, 0);
809 
810 	reply_msg.rm_direction = REPLY;
811 	reply_msg.rm_reply.rp_stat = MSG_ACCEPTED;
812 	reply_msg.acpted_rply.ar_stat = SUCCESS;
813 	reply_msg.acpted_rply.ar_verf = _null_auth;
814 	/*
815 	 *  xdr_results will be done in AUTH_UNWRAP.
816 	 */
817 	reply_msg.acpted_rply.ar_results.where = NULL;
818 	reply_msg.acpted_rply.ar_results.proc = xdr_void;
819 
820 	/*
821 	 * Decode and validate the response.
822 	 */
823 	if (!xdr_replymsg(xdrs, &reply_msg)) {
824 		p->cku_err.re_status = RPC_CANTDECODERES;
825 		p->cku_err.re_errno = EIO;
826 		(void) xdr_rpc_free_verifier(xdrs, &reply_msg);
827 		goto done1;
828 	}
829 
830 	_seterr_reply(&reply_msg, &(p->cku_err));
831 
832 	re_status = p->cku_err.re_status;
833 	if (re_status == RPC_SUCCESS) {
834 		/*
835 		 * Reply is good, check auth.
836 		 */
837 		if (!AUTH_VALIDATE(h->cl_auth,
838 				    &reply_msg.acpted_rply.ar_verf)) {
839 			p->cku_err.re_status = RPC_AUTHERROR;
840 			p->cku_err.re_why = AUTH_INVALIDRESP;
841 			RCSTAT_INCR(p->cku_stats, rcbadverfs);
842 			(void) xdr_rpc_free_verifier(xdrs, &reply_msg);
843 			goto tryread;
844 		}
845 		if (!AUTH_UNWRAP(h->cl_auth, xdrs, xdr_results, resultsp)) {
846 			p->cku_err.re_status = RPC_CANTDECODERES;
847 			p->cku_err.re_errno = EIO;
848 		}
849 		(void) xdr_rpc_free_verifier(xdrs, &reply_msg);
850 		goto done1;
851 	}
852 	/* set errno in case we can't recover */
853 	if (re_status != RPC_VERSMISMATCH &&
854 			    re_status != RPC_AUTHERROR &&
855 			    re_status != RPC_PROGVERSMISMATCH)
856 		p->cku_err.re_errno = EIO;
857 	/*
858 	 * Determine whether or not we're doing an RPC
859 	 * broadcast. Some server implementations don't
860 	 * follow RFC 1050, section 7.4.2 in that they
861 	 * don't remain silent when they see a proc
862 	 * they don't support. Therefore we keep trying
863 	 * to receive on RPC_PROCUNAVAIL, hoping to get
864 	 * a valid response from a compliant server.
865 	 */
866 	if (re_status == RPC_PROCUNAVAIL && p->cku_bcast) {
867 		(void) xdr_rpc_free_verifier(xdrs, &reply_msg);
868 		goto tryread;
869 	}
870 	if (re_status == RPC_AUTHERROR) {
871 		/*
872 		 * Maybe our credential need to be refreshed
873 		 */
874 		if (refreshes > 0 &&
875 		    AUTH_REFRESH(h->cl_auth, &reply_msg, p->cku_cred)) {
876 			/*
877 			 * The credential is refreshed. Try the request again.
878 			 * Even if stries == 0, we still retry as long as
879 			 * refreshes > 0. This prevents a soft authentication
880 			 * error turning into a hard one at an upper level.
881 			 */
882 			refreshes--;
883 			RCSTAT_INCR(p->cku_stats, rcbadcalls);
884 			RCSTAT_INCR(p->cku_stats, rcnewcreds);
885 
886 			(void) xdr_rpc_free_verifier(xdrs, &reply_msg);
887 			freemsg(mpdup);
888 			call_table_remove(call);
889 			mutex_enter(&call->call_lock);
890 			if (call->call_reply != NULL) {
891 				freemsg(call->call_reply);
892 				call->call_reply = NULL;
893 			}
894 			mutex_exit(&call->call_lock);
895 
896 			freemsg(resp);
897 			mpdup = NULL;
898 			goto call_again;
899 		}
900 		/*
901 		 * We have used the client handle to do an AUTH_REFRESH
902 		 * and the RPC status may be set to RPC_SUCCESS;
903 		 * Let's make sure to set it to RPC_AUTHERROR.
904 		 */
905 		p->cku_err.re_status = RPC_CANTDECODERES;
906 
907 		/*
908 		 * Map recoverable and unrecoverable
909 		 * authentication errors to appropriate errno
910 		 */
911 		switch (p->cku_err.re_why) {
912 		case AUTH_TOOWEAK:
913 			/*
914 			 * Could be an nfsportmon failure, set
915 			 * useresvport and try again.
916 			 */
917 			if (p->cku_useresvport != 1) {
918 				p->cku_useresvport = 1;
919 				(void) xdr_rpc_free_verifier(xdrs, &reply_msg);
920 				freemsg(mpdup);
921 
922 				call_table_remove(call);
923 				mutex_enter(&call->call_lock);
924 				if (call->call_reply != NULL) {
925 					freemsg(call->call_reply);
926 					call->call_reply = NULL;
927 				}
928 				mutex_exit(&call->call_lock);
929 
930 				freemsg(resp);
931 				mpdup = NULL;
932 				endpt = p->cku_endpnt;
933 				if (endpt->e_tiptr != NULL) {
934 					mutex_enter(&endpt->e_lock);
935 					endpt->e_flags &= ~ENDPNT_BOUND;
936 					(void) t_kclose(endpt->e_tiptr, 1);
937 					endpt->e_tiptr = NULL;
938 					mutex_exit(&endpt->e_lock);
939 
940 				}
941 
942 				p->cku_xid = alloc_xid();
943 				endpnt_rele(p->cku_endpnt);
944 				p->cku_endpnt = NULL;
945 				goto call_again;
946 			}
947 			/* FALLTHRU */
948 		case AUTH_BADCRED:
949 		case AUTH_BADVERF:
950 		case AUTH_INVALIDRESP:
951 		case AUTH_FAILED:
952 		case RPCSEC_GSS_NOCRED:
953 		case RPCSEC_GSS_FAILED:
954 			p->cku_err.re_errno = EACCES;
955 			break;
956 		case AUTH_REJECTEDCRED:
957 		case AUTH_REJECTEDVERF:
958 		default:
959 			p->cku_err.re_errno = EIO;
960 			break;
961 		}
962 		RPCLOG(1, "clnt_clts_kcallit : authentication failed "
963 		    "with RPC_AUTHERROR of type %d\n",
964 		    p->cku_err.re_why);
965 	}
966 
967 	(void) xdr_rpc_free_verifier(xdrs, &reply_msg);
968 
969 done1:
970 	call_table_remove(call);
971 	mutex_enter(&call->call_lock);
972 	if (call->call_reply != NULL) {
973 		freemsg(call->call_reply);
974 		call->call_reply = NULL;
975 	}
976 	mutex_exit(&call->call_lock);
977 	RPCLOG(64, "clnt_clts_kcallit_addr: xid 0x%x taken off dispatch list",
978 		p->cku_xid);
979 
980 done:
981 	if (resp != NULL) {
982 		freemsg(resp);
983 		resp = NULL;
984 	}
985 
986 	if ((p->cku_err.re_status != RPC_SUCCESS) &&
987 	    (p->cku_err.re_status != RPC_INTR) &&
988 	    (p->cku_err.re_status != RPC_UDERROR) &&
989 	    !IS_UNRECOVERABLE_RPC(p->cku_err.re_status)) {
990 		if (p->cku_feedback != NULL && stries == p->cku_retrys) {
991 			(*p->cku_feedback)(FEEDBACK_REXMIT1, procnum,
992 			    p->cku_feedarg);
993 		}
994 
995 		timout = backoff(timout);
996 		if (p->cku_timeall != (struct rpc_timers *)0)
997 			p->cku_timeall->rt_rtxcur = timout;
998 
999 		if (p->cku_err.re_status == RPC_SYSTEMERROR ||
1000 		    p->cku_err.re_status == RPC_CANTSEND) {
1001 			/*
1002 			 * Errors due to lack of resources, wait a bit
1003 			 * and try again.
1004 			 */
1005 			(void) delay(hz/10);
1006 			/* (void) sleep((caddr_t)&lbolt, PZERO-4); */
1007 		}
1008 		if (stries-- > 0) {
1009 			RCSTAT_INCR(p->cku_stats, rcretrans);
1010 			goto call_again;
1011 		}
1012 	}
1013 
1014 	if (mpdup != NULL)
1015 		freemsg(mpdup);
1016 
1017 	if (p->cku_err.re_status != RPC_SUCCESS) {
1018 		RCSTAT_INCR(p->cku_stats, rcbadcalls);
1019 	}
1020 
1021 	/*
1022 	 * Allow the endpoint to be held by the client handle in case this
1023 	 * RPC was not successful.  A retry may occur at a higher level and
1024 	 * in this case we may want to send the request over the same
1025 	 * source port.
1026 	 */
1027 	if (p->cku_err.re_status == RPC_SUCCESS && p->cku_endpnt != NULL) {
1028 		endpnt_rele(p->cku_endpnt);
1029 		p->cku_endpnt = NULL;
1030 	}
1031 
1032 	return (p->cku_err.re_status);
1033 }
1034 
1035 static enum clnt_stat
1036 clnt_clts_kcallit(CLIENT *h, rpcproc_t procnum, xdrproc_t xdr_args,
1037 	caddr_t argsp, xdrproc_t xdr_results, caddr_t resultsp,
1038 	struct timeval wait)
1039 {
1040 	return (clnt_clts_kcallit_addr(h, procnum, xdr_args, argsp,
1041 				xdr_results, resultsp, wait, NULL));
1042 }
1043 
1044 /*
1045  * Return error info on this handle.
1046  */
1047 static void
1048 clnt_clts_kerror(CLIENT *h, struct rpc_err *err)
1049 {
1050 	/* LINTED pointer alignment */
1051 	struct cku_private *p = htop(h);
1052 
1053 	*err = p->cku_err;
1054 }
1055 
1056 static bool_t
1057 clnt_clts_kfreeres(CLIENT *h, xdrproc_t xdr_res, caddr_t res_ptr)
1058 {
1059 	/* LINTED pointer alignment */
1060 	struct cku_private *p = htop(h);
1061 	XDR *xdrs;
1062 
1063 	xdrs = &(p->cku_outxdr);
1064 	xdrs->x_op = XDR_FREE;
1065 	return ((*xdr_res)(xdrs, res_ptr));
1066 }
1067 
1068 /*ARGSUSED*/
1069 static void
1070 clnt_clts_kabort(CLIENT *h)
1071 {
1072 }
1073 
1074 static bool_t
1075 clnt_clts_kcontrol(CLIENT *h, int cmd, char *arg)
1076 {
1077 	/* LINTED pointer alignment */
1078 	struct cku_private *p = htop(h);
1079 
1080 	switch (cmd) {
1081 	case CLSET_XID:
1082 		p->cku_xid = *((uint32_t *)arg);
1083 		return (TRUE);
1084 
1085 	case CLGET_XID:
1086 		*((uint32_t *)arg) = p->cku_xid;
1087 		return (TRUE);
1088 
1089 	case CLSET_BCAST:
1090 		p->cku_bcast = *((uint32_t *)arg);
1091 		return (TRUE);
1092 
1093 	case CLGET_BCAST:
1094 		*((uint32_t *)arg) = p->cku_bcast;
1095 		return (TRUE);
1096 	case CLSET_BINDRESVPORT:
1097 		if (arg == NULL)
1098 			return (FALSE);
1099 
1100 		if (*(int *)arg != 1 && *(int *)arg != 0)
1101 			return (FALSE);
1102 
1103 		p->cku_useresvport = *(int *)arg;
1104 
1105 		return (TRUE);
1106 
1107 	case CLGET_BINDRESVPORT:
1108 		if (arg == NULL)
1109 			return (FALSE);
1110 
1111 		*(int *)arg = p->cku_useresvport;
1112 
1113 		return (TRUE);
1114 
1115 	default:
1116 		return (FALSE);
1117 	}
1118 }
1119 
1120 /*
1121  * Destroy rpc handle.
1122  * Frees the space used for output buffer, private data, and handle
1123  * structure, and the file pointer/TLI data on last reference.
1124  */
1125 static void
1126 clnt_clts_kdestroy(CLIENT *h)
1127 {
1128 	/* LINTED pointer alignment */
1129 	struct cku_private *p = htop(h);
1130 	calllist_t *call = &p->cku_call;
1131 
1132 	int plen;
1133 
1134 	RPCLOG(8, "clnt_clts_kdestroy h: %p\n", (void *)h);
1135 	RPCLOG(8, "clnt_clts_kdestroy h: xid=0x%x\n", p->cku_xid);
1136 
1137 	if (p->cku_endpnt != NULL)
1138 		endpnt_rele(p->cku_endpnt);
1139 
1140 	cv_destroy(&call->call_cv);
1141 	mutex_destroy(&call->call_lock);
1142 
1143 	plen = strlen(p->cku_config.knc_protofmly) + 1;
1144 	kmem_free(p->cku_config.knc_protofmly, plen);
1145 	kmem_free(p->cku_addr.buf, p->cku_addr.maxlen);
1146 	kmem_free(p, sizeof (*p));
1147 }
1148 
1149 /*
1150  * The connectionless (CLTS) kRPC endpoint management subsystem.
1151  *
1152  * Because endpoints are potentially shared among threads making RPC calls,
1153  * they are managed in a pool according to type (endpnt_type_t).  Each
1154  * endpnt_type_t points to a list of usable endpoints through the e_pool
1155  * field, which is of type list_t.  list_t is a doubly-linked list.
1156  * The number of endpoints in the pool is stored in the e_cnt field of
1157  * endpnt_type_t and the endpoints are reference counted using the e_ref field
1158  * in the endpnt_t structure.
1159  *
1160  * As an optimization, endpoints that have no references are also linked
1161  * to an idle list via e_ilist which is also of type list_t.  When a thread
1162  * calls endpnt_get() to obtain a transport endpoint, the idle list is first
1163  * consulted and if such an endpoint exists, it is removed from the idle list
1164  * and returned to the caller.
1165  *
1166  * If the idle list is empty, then a check is made to see if more endpoints
1167  * can be created.  If so, we proceed and create a new endpoint which is added
1168  * to the pool and returned to the caller.  If we have reached the limit and
1169  * cannot make a new endpoint then one is returned to the caller via round-
1170  * robin policy.
1171  *
1172  * When an endpoint is placed on the idle list by a thread calling
1173  * endpnt_rele(), it is timestamped and then a reaper taskq is scheduled to
1174  * be dispatched if one hasn't already been.  When the timer fires, the
1175  * taskq traverses the idle list and checks to see which endpoints are
1176  * eligible to be closed.  It determines this by checking if the timestamp
1177  * when the endpoint was released has exceeded the the threshold for how long
1178  * it should stay alive.
1179  *
1180  * endpnt_t structures remain persistent until the memory reclaim callback,
1181  * endpnt_reclaim(), is invoked.
1182  *
1183  * Here is an example of how the data structures would be laid out by the
1184  * subsystem:
1185  *
1186  *       endpnt_type_t
1187  *
1188  *	 loopback		                  inet
1189  *	 _______________	                  ______________
1190  *	| e_next        |----------------------->| e_next       |---->>
1191  *	| e_pool        |<---+                   | e_pool       |<----+
1192  *	| e_ilist       |<---+--+                | e_ilist      |<----+--+
1193  *   +->| e_pcurr       |----+--+--+	      +->| e_pcurr      |-----+--+--+
1194  *   |	| ...           |    |  |  |	      |	 | ...	        |     |  |  |
1195  *   |	| e_itimer (90) |    |  |  |	      |	 | e_itimer (0) |     |  |  |
1196  *   |	| e_cnt (1)     |    |  |  |	      |	 | e_cnt (3)    |     |  |  |
1197  *   |	+---------------+    |  |  |	      |	 +--------------+     |  |  |
1198  *   |			     |  |  |	      |			      |  |  |
1199  *   |   endpnt_t            |  |  |          |	                      |  |  |
1200  *   |	 ____________        |  |  |	      |	  ____________        |  |  |
1201  *   |	| e_node     |<------+  |  |	      |	 | e_node     |<------+  |  |
1202  *   |	| e_idle     |<---------+  |	      |	 | e_idle     |       |  |  |
1203  *   +--| e_type     |<------------+	      +--| e_type     |       |  |  |
1204  *	| e_tiptr    |                        |  | e_tiptr    |       |  |  |
1205  *      | ...	     |		              |	 | ...	      |       |  |  |
1206  *	| e_lock     |		              |	 | e_lock     |       |  |  |
1207  *	| ...        |		              |	 | ...	      |       |  |  |
1208  *      | e_ref (0)  |		              |	 | e_ref (2)  |       |  |  |
1209  *	| e_itime    |	                      |	 | e_itime    |       |  |  |
1210  *	+------------+		              |	 +------------+       |  |  |
1211  *					      |			      |  |  |
1212  *					      |			      |  |  |
1213  *					      |	  ____________        |  |  |
1214  *					      |	 | e_node     |<------+  |  |
1215  *					      |	 | e_idle     |<------+--+  |
1216  *					      +--| e_type     |       |     |
1217  *					      |	 | e_tiptr    |       |     |
1218  *					      |	 | ...	      |       |     |
1219  *					      |	 | e_lock     |       |     |
1220  *					      |	 | ...	      |       |     |
1221  *					      |	 | e_ref (0)  |       |     |
1222  *					      |	 | e_itime    |       |     |
1223  *					      |	 +------------+       |     |
1224  *					      |			      |     |
1225  *					      |			      |     |
1226  *					      |	  ____________        |     |
1227  *					      |	 | e_node     |<------+     |
1228  *					      |	 | e_idle     |             |
1229  *					      +--| e_type     |<------------+
1230  *						 | e_tiptr    |
1231  *						 | ...	      |
1232  *						 | e_lock     |
1233  *						 | ...	      |
1234  *						 | e_ref (1)  |
1235  *						 | e_itime    |
1236  *						 +------------+
1237  *
1238  * Endpoint locking strategy:
1239  *
1240  * The following functions manipulate lists which hold the endpoint and the
1241  * endpoints themselves:
1242  *
1243  * endpnt_get()/check_endpnt()/endpnt_rele()/endpnt_reap()/do_endpnt_reclaim()
1244  *
1245  * Lock description follows:
1246  *
1247  * endpnt_type_lock: Global reader/writer lock which protects accesses to the
1248  *		     endpnt_type_list.
1249  *
1250  * e_plock: Lock defined in the endpnt_type_t.  It is intended to
1251  *	    protect accesses to the pool of endopints (e_pool) for a given
1252  *	    endpnt_type_t.
1253  *
1254  * e_ilock: Lock defined in endpnt_type_t.  It is intended to protect accesses
1255  *	    to the idle list (e_ilist) of available endpoints for a given
1256  *	    endpnt_type_t.  It also protects access to the e_itimer, e_async_cv,
1257  *	    and e_async_count fields in endpnt_type_t.
1258  *
1259  * e_lock: Lock defined in the endpnt structure.  It is intended to protect
1260  *	   flags, cv, and ref count.
1261  *
1262  * The order goes as follows so as not to induce deadlock.
1263  *
1264  * endpnt_type_lock -> e_plock -> e_ilock -> e_lock
1265  *
1266  * Interaction with Zones and shutting down:
1267  *
1268  * endpnt_type_ts are uniquely identified by the (e_zoneid, e_rdev, e_protofmly)
1269  * tuple, which means that a zone may not reuse another zone's idle endpoints
1270  * without first doing a t_kclose().
1271  *
1272  * A zone's endpnt_type_ts are destroyed when a zone is shut down; e_async_cv
1273  * and e_async_count are used to keep track of the threads in endpnt_taskq
1274  * trying to reap endpnt_ts in the endpnt_type_t.
1275  */
1276 
1277 /*
1278  * Allocate and initialize an endpnt_type_t
1279  */
1280 static struct endpnt_type *
1281 endpnt_type_create(struct knetconfig *config)
1282 {
1283 	struct endpnt_type	*etype;
1284 
1285 	/*
1286 	 * Allocate a new endpoint type to hang a list of
1287 	 * endpoints off of it.
1288 	 */
1289 	etype = kmem_alloc(sizeof (struct endpnt_type), KM_SLEEP);
1290 	etype->e_next = NULL;
1291 	etype->e_pcurr = NULL;
1292 	etype->e_itimer = 0;
1293 	etype->e_cnt = 0;
1294 
1295 	(void) strncpy(etype->e_protofmly, config->knc_protofmly, KNC_STRSIZE);
1296 	mutex_init(&etype->e_plock, NULL, MUTEX_DEFAULT, NULL);
1297 	mutex_init(&etype->e_ilock, NULL, MUTEX_DEFAULT, NULL);
1298 	etype->e_rdev = config->knc_rdev;
1299 	etype->e_zoneid = rpc_zoneid();
1300 	etype->e_async_count = 0;
1301 	cv_init(&etype->e_async_cv, NULL, CV_DEFAULT, NULL);
1302 
1303 	list_create(&etype->e_pool, sizeof (endpnt_t),
1304 			offsetof(endpnt_t, e_node));
1305 	list_create(&etype->e_ilist, sizeof (endpnt_t),
1306 			offsetof(endpnt_t, e_idle));
1307 
1308 	/*
1309 	 * Check to see if we need to create a taskq for endpoint
1310 	 * reaping
1311 	 */
1312 	mutex_enter(&endpnt_taskq_lock);
1313 	if (taskq_created == FALSE) {
1314 		taskq_created = TRUE;
1315 		mutex_exit(&endpnt_taskq_lock);
1316 		ASSERT(endpnt_taskq == NULL);
1317 		endpnt_taskq = taskq_create("clts_endpnt_taskq", 1,
1318 						minclsyspri, 200, INT_MAX, 0);
1319 	} else
1320 		mutex_exit(&endpnt_taskq_lock);
1321 
1322 	return (etype);
1323 }
1324 
1325 /*
1326  * Free an endpnt_type_t
1327  */
1328 static void
1329 endpnt_type_free(struct endpnt_type *etype)
1330 {
1331 	mutex_destroy(&etype->e_plock);
1332 	mutex_destroy(&etype->e_ilock);
1333 	list_destroy(&etype->e_pool);
1334 	list_destroy(&etype->e_ilist);
1335 	kmem_free(etype, sizeof (endpnt_type_t));
1336 }
1337 
1338 /*
1339  * Check the endpoint to ensure that it is suitable for use.
1340  *
1341  * Possible return values:
1342  *
1343  * return (1) - Endpoint is established, but needs to be re-opened.
1344  * return (0) && *newp == NULL - Endpoint is established, but unusable.
1345  * return (0) && *newp != NULL - Endpoint is established and usable.
1346  */
1347 static int
1348 check_endpnt(struct endpnt *endp, struct endpnt **newp)
1349 {
1350 	*newp = endp;
1351 
1352 	mutex_enter(&endp->e_lock);
1353 	ASSERT(endp->e_ref >= 1);
1354 
1355 	/*
1356 	 * The first condition we check for is if the endpoint has been
1357 	 * allocated, but is unusable either because it has been closed or
1358 	 * has been marked stale.  Only *one* thread will be allowed to
1359 	 * execute the then clause.  This is enforced becuase the first thread
1360 	 * to check this condition will clear the flags, so that subsequent
1361 	 * thread(s) checking this endpoint will move on.
1362 	 */
1363 	if ((endp->e_flags & ENDPNT_ESTABLISHED) &&
1364 		(!(endp->e_flags & ENDPNT_BOUND) ||
1365 		(endp->e_flags & ENDPNT_STALE))) {
1366 		/*
1367 		 * Clear the flags here since they will be
1368 		 * set again by this thread.  They need to be
1369 		 * individually cleared because we want to maintain
1370 		 * the state for ENDPNT_ONIDLE.
1371 		 */
1372 		endp->e_flags &= ~(ENDPNT_ESTABLISHED |
1373 				ENDPNT_WAITING | ENDPNT_BOUND |	ENDPNT_STALE);
1374 		mutex_exit(&endp->e_lock);
1375 		return (1);
1376 	}
1377 
1378 	/*
1379 	 * The second condition is meant for any thread that is waiting for
1380 	 * an endpoint to become established.  It will cv_wait() until
1381 	 * the condition for the endpoint has been changed to ENDPNT_BOUND or
1382 	 * ENDPNT_STALE.
1383 	 */
1384 	while (!(endp->e_flags & ENDPNT_BOUND) &&
1385 		!(endp->e_flags & ENDPNT_STALE)) {
1386 		endp->e_flags |= ENDPNT_WAITING;
1387 		cv_wait(&endp->e_cv, &endp->e_lock);
1388 	}
1389 
1390 	ASSERT(endp->e_flags & ENDPNT_ESTABLISHED);
1391 
1392 	/*
1393 	 * The last case we check for is if the endpoint has been marked stale.
1394 	 * If this is the case then set *newp to NULL and return, so that the
1395 	 * caller is notified of the error and can take appropriate action.
1396 	 */
1397 	if (endp->e_flags & ENDPNT_STALE) {
1398 		endp->e_ref--;
1399 		*newp = NULL;
1400 	}
1401 	mutex_exit(&endp->e_lock);
1402 	return (0);
1403 }
1404 
1405 #ifdef DEBUG
1406 /*
1407  * Provide a fault injection setting to test error conditions.
1408  */
1409 static int endpnt_get_return_null = 0;
1410 #endif
1411 
1412 /*
1413  * Returns a handle (struct endpnt *) to an open and bound endpoint
1414  * specified by the knetconfig passed in.  Returns NULL if no valid endpoint
1415  * can be obtained.
1416  */
1417 static struct endpnt *
1418 endpnt_get(struct knetconfig *config, int useresvport)
1419 {
1420 	struct endpnt_type	*n_etype = NULL;
1421 	struct endpnt_type	*np = NULL;
1422 	struct endpnt		*new = NULL;
1423 	struct endpnt		*endp = NULL;
1424 	struct endpnt		*next = NULL;
1425 	TIUSER			*tiptr = NULL;
1426 	int			rtries = BINDRESVPORT_RETRIES;
1427 	int			i = 0;
1428 	int			error;
1429 	int			retval;
1430 	zoneid_t		zoneid = rpc_zoneid();
1431 
1432 	RPCLOG(1, "endpnt_get: protofmly %s, ", config->knc_protofmly);
1433 	RPCLOG(1, "rdev %ld\n", config->knc_rdev);
1434 
1435 #ifdef DEBUG
1436 	/*
1437 	 * Inject fault if desired.  Pretend we have a stale endpoint
1438 	 * and return NULL.
1439 	 */
1440 	if (endpnt_get_return_null > 0) {
1441 		endpnt_get_return_null--;
1442 		return (NULL);
1443 	}
1444 #endif
1445 	rw_enter(&endpnt_type_lock, RW_READER);
1446 
1447 top:
1448 	for (np = endpnt_type_list; np != NULL; np = np->e_next)
1449 		if ((np->e_zoneid == zoneid) &&
1450 		    (np->e_rdev == config->knc_rdev) &&
1451 		    (strcmp(np->e_protofmly,
1452 			    config->knc_protofmly) == 0))
1453 			break;
1454 
1455 	if (np == NULL && n_etype != NULL) {
1456 		ASSERT(rw_write_held(&endpnt_type_lock));
1457 
1458 		/*
1459 		 * Link the endpoint type onto the list
1460 		 */
1461 		n_etype->e_next = endpnt_type_list;
1462 		endpnt_type_list = n_etype;
1463 		np = n_etype;
1464 		n_etype = NULL;
1465 	}
1466 
1467 	if (np == NULL) {
1468 		/*
1469 		 * The logic here is that we were unable to find an
1470 		 * endpnt_type_t that matched our criteria, so we allocate a
1471 		 * new one.  Because kmem_alloc() needs to be called with
1472 		 * KM_SLEEP, we drop our locks so that we don't induce
1473 		 * deadlock.  After allocating and initializing the
1474 		 * endpnt_type_t, we reaquire the lock and go back to check
1475 		 * if this entry needs to be added to the list.  Since we do
1476 		 * some operations without any locking other threads may
1477 		 * have been looking for the same endpnt_type_t and gone
1478 		 * through this code path.  We check for this case and allow
1479 		 * one thread to link its endpnt_type_t to the list and the
1480 		 * other threads will simply free theirs.
1481 		 */
1482 		rw_exit(&endpnt_type_lock);
1483 		n_etype = endpnt_type_create(config);
1484 
1485 		/*
1486 		 * We need to reaquire the lock with RW_WRITER here so that
1487 		 * we can safely link the new endpoint type onto the list.
1488 		 */
1489 		rw_enter(&endpnt_type_lock, RW_WRITER);
1490 		goto top;
1491 	}
1492 
1493 	rw_exit(&endpnt_type_lock);
1494 	/*
1495 	 * If n_etype is not NULL, then another thread was able to
1496 	 * insert an endpnt_type_t of this type  onto the list before
1497 	 * we did.  Go ahead and free ours.
1498 	 */
1499 	if (n_etype != NULL)
1500 		endpnt_type_free(n_etype);
1501 
1502 	mutex_enter(&np->e_ilock);
1503 	/*
1504 	 * The algorithm to hand out endpoints is to first
1505 	 * give out those that are idle if such endpoints
1506 	 * exist.  Otherwise, create a new one if we haven't
1507 	 * reached the max threshold.  Finally, we give out
1508 	 * endpoints in a pseudo LRU fashion (round-robin).
1509 	 *
1510 	 * Note:  The idle list is merely a hint of those endpoints
1511 	 * that should be idle.  There exists a window after the
1512 	 * endpoint is released and before it is linked back onto the
1513 	 * idle list where a thread could get a reference to it and
1514 	 * use it.  This is okay, since the reference counts will
1515 	 * still be consistent.
1516 	 */
1517 	if ((endp = (endpnt_t *)list_head(&np->e_ilist)) != NULL) {
1518 		timeout_id_t t_id = 0;
1519 
1520 		mutex_enter(&endp->e_lock);
1521 		endp->e_ref++;
1522 		endp->e_itime = 0;
1523 		endp->e_flags &= ~ENDPNT_ONIDLE;
1524 		mutex_exit(&endp->e_lock);
1525 
1526 		/*
1527 		 * Pop the endpoint off the idle list and hand it off
1528 		 */
1529 		list_remove(&np->e_ilist, endp);
1530 
1531 		if (np->e_itimer != 0) {
1532 			t_id = np->e_itimer;
1533 			np->e_itimer = 0;
1534 		}
1535 		mutex_exit(&np->e_ilock);
1536 		/*
1537 		 * Reset the idle timer if it has been set
1538 		 */
1539 		if (t_id != (timeout_id_t)0)
1540 			(void) untimeout(t_id);
1541 
1542 		if (check_endpnt(endp, &new) == 0)
1543 			return (new);
1544 	} else if (np->e_cnt >= clnt_clts_max_endpoints) {
1545 		/*
1546 		 * There are no idle endpoints currently, so
1547 		 * create a new one if we have not reached the maximum or
1548 		 * hand one out in round-robin.
1549 		 */
1550 		mutex_exit(&np->e_ilock);
1551 		mutex_enter(&np->e_plock);
1552 		endp = np->e_pcurr;
1553 		mutex_enter(&endp->e_lock);
1554 		endp->e_ref++;
1555 		mutex_exit(&endp->e_lock);
1556 
1557 		ASSERT(endp != NULL);
1558 		/*
1559 		 * Advance the pointer to the next eligible endpoint, if
1560 		 * necessary.
1561 		 */
1562 		if (np->e_cnt > 1) {
1563 			next = (endpnt_t *)list_next(&np->e_pool, np->e_pcurr);
1564 			if (next == NULL)
1565 				next = (endpnt_t *)list_head(&np->e_pool);
1566 			np->e_pcurr = next;
1567 		}
1568 
1569 		mutex_exit(&np->e_plock);
1570 
1571 		/*
1572 		 * We need to check to see if this endpoint is bound or
1573 		 * not.  If it is in progress then just wait until
1574 		 * the set up is complete
1575 		 */
1576 		if (check_endpnt(endp, &new) == 0)
1577 			return (new);
1578 	} else {
1579 		mutex_exit(&np->e_ilock);
1580 		mutex_enter(&np->e_plock);
1581 
1582 		/*
1583 		 * Allocate a new endpoint to use.  If we can't allocate any
1584 		 * more memory then use one that is already established if any
1585 		 * such endpoints exist.
1586 		 */
1587 		new = kmem_cache_alloc(endpnt_cache, KM_NOSLEEP);
1588 		if (new == NULL) {
1589 			RPCLOG0(1, "endpnt_get: kmem_cache_alloc failed\n");
1590 			/*
1591 			 * Try to recover by using an existing endpoint.
1592 			 */
1593 			if (np->e_cnt <= 0) {
1594 				mutex_exit(&np->e_plock);
1595 				return (NULL);
1596 			}
1597 			endp = np->e_pcurr;
1598 			if ((next = list_next(&np->e_pool, np->e_pcurr)) !=
1599 				NULL)
1600 				np->e_pcurr = next;
1601 			ASSERT(endp != NULL);
1602 			mutex_enter(&endp->e_lock);
1603 			endp->e_ref++;
1604 			mutex_exit(&endp->e_lock);
1605 			mutex_exit(&np->e_plock);
1606 
1607 			if (check_endpnt(endp, &new) == 0)
1608 				return (new);
1609 		} else {
1610 			/*
1611 			 * Partially init an endpoint structure and put
1612 			 * it on the list, so that other interested threads
1613 			 * know that one is being created
1614 			 */
1615 			bzero(new, sizeof (struct endpnt));
1616 
1617 			cv_init(&new->e_cv, NULL, CV_DEFAULT, NULL);
1618 			mutex_init(&new->e_lock, NULL, MUTEX_DEFAULT, NULL);
1619 			new->e_ref = 1;
1620 			new->e_type = np;
1621 
1622 			/*
1623 			 * Link the endpoint into the pool.
1624 			 */
1625 			list_insert_head(&np->e_pool, new);
1626 			np->e_cnt++;
1627 			if (np->e_pcurr == NULL)
1628 				np->e_pcurr = new;
1629 			mutex_exit(&np->e_plock);
1630 		}
1631 	}
1632 
1633 	/*
1634 	 * The transport should be opened with sufficient privs
1635 	 */
1636 	error = t_kopen(NULL, config->knc_rdev, FREAD|FWRITE|FNDELAY, &tiptr,
1637 	    kcred);
1638 	if (error) {
1639 		RPCLOG(1, "endpnt_get: t_kopen: %d\n", error);
1640 		goto bad;
1641 	}
1642 
1643 	new->e_tiptr = tiptr;
1644 	rpc_poptimod(tiptr->fp->f_vnode);
1645 
1646 	/*
1647 	 * Allow the kernel to push the module on behalf of the user.
1648 	 */
1649 	error = strioctl(tiptr->fp->f_vnode, I_PUSH, (intptr_t)"rpcmod", 0,
1650 			K_TO_K, kcred, &retval);
1651 	if (error) {
1652 		RPCLOG(1, "endpnt_get: kstr_push on rpcmod failed %d\n", error);
1653 		goto bad;
1654 	}
1655 
1656 	error = strioctl(tiptr->fp->f_vnode, RPC_CLIENT, 0, 0, K_TO_K,
1657 				kcred, &retval);
1658 	if (error) {
1659 		RPCLOG(1, "endpnt_get: strioctl failed %d\n", error);
1660 		goto bad;
1661 	}
1662 
1663 	/*
1664 	 * Connectionless data flow should bypass the stream head.
1665 	 */
1666 	new->e_wq = tiptr->fp->f_vnode->v_stream->sd_wrq->q_next;
1667 
1668 	error = strioctl(tiptr->fp->f_vnode, I_PUSH, (intptr_t)"timod", 0,
1669 			K_TO_K, kcred, &retval);
1670 	if (error) {
1671 		RPCLOG(1, "endpnt_get: kstr_push on timod failed %d\n", error);
1672 		goto bad;
1673 	}
1674 
1675 	/*
1676 	 * Attempt to bind the endpoint.  If we fail then propogate
1677 	 * error back to calling subsystem, so that it can be handled
1678 	 * appropriately.
1679 	 * If the caller has not specified reserved port usage then
1680 	 * take the system default.
1681 	 */
1682 	if (useresvport == -1)
1683 		useresvport = clnt_clts_do_bindresvport;
1684 
1685 	if (useresvport &&
1686 	    (strcmp(config->knc_protofmly, NC_INET) == 0 ||
1687 		strcmp(config->knc_protofmly, NC_INET6) == 0)) {
1688 
1689 		while ((error =
1690 			bindresvport(new->e_tiptr, NULL, NULL, FALSE)) != 0) {
1691 			RPCLOG(1,
1692 				"endpnt_get: bindresvport error %d\n",
1693 				error);
1694 			if (error != EPROTO) {
1695 				if (rtries-- <= 0)
1696 					goto bad;
1697 
1698 				delay(hz << i++);
1699 				continue;
1700 			}
1701 
1702 			(void) t_kclose(new->e_tiptr, 1);
1703 			/*
1704 			 * reopen with all privileges
1705 			 */
1706 			error = t_kopen(NULL, config->knc_rdev,
1707 					FREAD|FWRITE|FNDELAY,
1708 					&new->e_tiptr, kcred);
1709 			if (error) {
1710 				RPCLOG(1, "endpnt_get: t_kopen: %d\n", error);
1711 					new->e_tiptr = NULL;
1712 					goto bad;
1713 			}
1714 		}
1715 	} else if ((error = t_kbind(new->e_tiptr, NULL, NULL)) != 0) {
1716 		RPCLOG(1, "endpnt_get: t_kbind failed: %d\n", error);
1717 		goto bad;
1718 	}
1719 
1720 	/*
1721 	 * Set the flags and notify and waiters that we have an established
1722 	 * endpoint.
1723 	 */
1724 	mutex_enter(&new->e_lock);
1725 	new->e_flags |= ENDPNT_ESTABLISHED;
1726 	new->e_flags |= ENDPNT_BOUND;
1727 	if (new->e_flags & ENDPNT_WAITING) {
1728 		cv_broadcast(&new->e_cv);
1729 		new->e_flags &= ~ENDPNT_WAITING;
1730 	}
1731 	mutex_exit(&new->e_lock);
1732 
1733 	return (new);
1734 
1735 bad:
1736 	ASSERT(new != NULL);
1737 	/*
1738 	 * mark this endpoint as stale and notify any threads waiting
1739 	 * on this endpoint that it will be going away.
1740 	 */
1741 	mutex_enter(&new->e_lock);
1742 	if (new->e_ref > 0) {
1743 		new->e_flags |= ENDPNT_ESTABLISHED;
1744 		new->e_flags |= ENDPNT_STALE;
1745 		if (new->e_flags & ENDPNT_WAITING) {
1746 			cv_broadcast(&new->e_cv);
1747 			new->e_flags &= ~ENDPNT_WAITING;
1748 		}
1749 	}
1750 	new->e_ref--;
1751 	new->e_tiptr = NULL;
1752 	mutex_exit(&new->e_lock);
1753 
1754 	/*
1755 	 * If there was a transport endopoint opened, then close it.
1756 	 */
1757 	if (tiptr != NULL)
1758 		(void) t_kclose(tiptr, 1);
1759 
1760 	return (NULL);
1761 }
1762 
1763 /*
1764  * Release a referece to the endpoint
1765  */
1766 static void
1767 endpnt_rele(struct endpnt *sp)
1768 {
1769 	mutex_enter(&sp->e_lock);
1770 	ASSERT(sp->e_ref > 0);
1771 	sp->e_ref--;
1772 	/*
1773 	 * If the ref count is zero, then start the idle timer and link
1774 	 * the endpoint onto the idle list.
1775 	 */
1776 	if (sp->e_ref == 0) {
1777 		sp->e_itime = gethrestime_sec();
1778 
1779 		/*
1780 		 * Check to see if the endpoint is already linked to the idle
1781 		 * list, so that we don't try to reinsert it.
1782 		 */
1783 		if (sp->e_flags & ENDPNT_ONIDLE) {
1784 			mutex_exit(&sp->e_lock);
1785 			mutex_enter(&sp->e_type->e_ilock);
1786 			endpnt_reap_settimer(sp->e_type);
1787 			mutex_exit(&sp->e_type->e_ilock);
1788 			return;
1789 		}
1790 
1791 		sp->e_flags |= ENDPNT_ONIDLE;
1792 		mutex_exit(&sp->e_lock);
1793 		mutex_enter(&sp->e_type->e_ilock);
1794 		list_insert_tail(&sp->e_type->e_ilist, sp);
1795 		endpnt_reap_settimer(sp->e_type);
1796 		mutex_exit(&sp->e_type->e_ilock);
1797 	} else
1798 		mutex_exit(&sp->e_lock);
1799 }
1800 
1801 static void
1802 endpnt_reap_settimer(endpnt_type_t *etp)
1803 {
1804 	if (etp->e_itimer == (timeout_id_t)0)
1805 		etp->e_itimer = timeout(endpnt_reap_dispatch, (void *)etp,
1806 					clnt_clts_taskq_dispatch_interval);
1807 }
1808 
1809 static void
1810 endpnt_reap_dispatch(void *a)
1811 {
1812 	endpnt_type_t *etp = a;
1813 
1814 	/*
1815 	 * The idle timer has fired, so dispatch the taskq to close the
1816 	 * endpoint.
1817 	 */
1818 	if (taskq_dispatch(endpnt_taskq, (task_func_t *)endpnt_reap, etp,
1819 	    TQ_NOSLEEP) == NULL)
1820 		return;
1821 	mutex_enter(&etp->e_ilock);
1822 	etp->e_async_count++;
1823 	mutex_exit(&etp->e_ilock);
1824 }
1825 
1826 /*
1827  * Traverse the idle list and close those endpoints that have reached their
1828  * timeout interval.
1829  */
1830 static void
1831 endpnt_reap(endpnt_type_t *etp)
1832 {
1833 	struct endpnt *e;
1834 	struct endpnt *next_node = NULL;
1835 
1836 	mutex_enter(&etp->e_ilock);
1837 	e = list_head(&etp->e_ilist);
1838 	while (e != NULL) {
1839 		next_node = list_next(&etp->e_ilist, e);
1840 
1841 		mutex_enter(&e->e_lock);
1842 		if (e->e_ref > 0) {
1843 			mutex_exit(&e->e_lock);
1844 			e = next_node;
1845 			continue;
1846 		}
1847 
1848 		ASSERT(e->e_ref == 0);
1849 		if (e->e_itime > 0 &&
1850 		    (e->e_itime + clnt_clts_endpoint_reap_interval) <
1851 		    gethrestime_sec()) {
1852 			e->e_flags &= ~ENDPNT_BOUND;
1853 			(void) t_kclose(e->e_tiptr, 1);
1854 			e->e_tiptr = NULL;
1855 			e->e_itime = 0;
1856 		}
1857 		mutex_exit(&e->e_lock);
1858 		e = next_node;
1859 	}
1860 	etp->e_itimer = 0;
1861 	if (--etp->e_async_count == 0)
1862 		cv_signal(&etp->e_async_cv);
1863 	mutex_exit(&etp->e_ilock);
1864 }
1865 
1866 static void
1867 endpnt_reclaim(zoneid_t zoneid)
1868 {
1869 	struct endpnt_type *np;
1870 	struct endpnt *e;
1871 	struct endpnt *next_node = NULL;
1872 	list_t free_list;
1873 	int rcnt = 0;
1874 
1875 	list_create(&free_list, sizeof (endpnt_t), offsetof(endpnt_t, e_node));
1876 
1877 	RPCLOG0(1, "endpnt_reclaim: reclaim callback started\n");
1878 	rw_enter(&endpnt_type_lock, RW_READER);
1879 	for (np = endpnt_type_list; np != NULL; np = np->e_next) {
1880 		if (zoneid != ALL_ZONES && zoneid != np->e_zoneid)
1881 			continue;
1882 
1883 		mutex_enter(&np->e_plock);
1884 		RPCLOG(1, "endpnt_reclaim: protofmly %s, ",
1885 			np->e_protofmly);
1886 		RPCLOG(1, "rdev %ld\n", np->e_rdev);
1887 		RPCLOG(1, "endpnt_reclaim: found %d endpoint(s)\n",
1888 			np->e_cnt);
1889 
1890 		if (np->e_cnt == 0) {
1891 			mutex_exit(&np->e_plock);
1892 			continue;
1893 		}
1894 
1895 		/*
1896 		 * The nice thing about maintaining an idle list is that if
1897 		 * there are any endpoints to reclaim, they are going to be
1898 		 * on this list.  Just go through and reap the one's that
1899 		 * have ref counts of zero.
1900 		 */
1901 		mutex_enter(&np->e_ilock);
1902 		e = list_head(&np->e_ilist);
1903 		while (e != NULL) {
1904 			next_node = list_next(&np->e_ilist, e);
1905 			mutex_enter(&e->e_lock);
1906 			if (e->e_ref > 0) {
1907 				mutex_exit(&e->e_lock);
1908 				e = next_node;
1909 				continue;
1910 			}
1911 			ASSERT(e->e_ref == 0);
1912 			mutex_exit(&e->e_lock);
1913 
1914 			list_remove(&np->e_ilist, e);
1915 			list_remove(&np->e_pool, e);
1916 			list_insert_head(&free_list, e);
1917 
1918 			rcnt++;
1919 			np->e_cnt--;
1920 			e = next_node;
1921 		}
1922 		mutex_exit(&np->e_ilock);
1923 		/*
1924 		 * Reset the current pointer to be safe
1925 		 */
1926 		if ((e = (struct endpnt *)list_head(&np->e_pool)) != NULL)
1927 			np->e_pcurr = e;
1928 		else {
1929 			ASSERT(np->e_cnt == 0);
1930 			np->e_pcurr = NULL;
1931 		}
1932 
1933 		mutex_exit(&np->e_plock);
1934 	}
1935 	rw_exit(&endpnt_type_lock);
1936 
1937 	while ((e = list_head(&free_list)) != NULL) {
1938 		list_remove(&free_list, e);
1939 		if (e->e_tiptr != NULL)
1940 			(void) t_kclose(e->e_tiptr, 1);
1941 
1942 		cv_destroy(&e->e_cv);
1943 		mutex_destroy(&e->e_lock);
1944 		kmem_cache_free(endpnt_cache, e);
1945 	}
1946 	list_destroy(&free_list);
1947 	RPCLOG(1, "endpnt_reclaim: reclaimed %d endpoint(s)\n", rcnt);
1948 }
1949 
1950 /*
1951  * Endpoint reclaim zones destructor callback routine.
1952  *
1953  * After reclaiming any cached entries, we basically go through the endpnt_type
1954  * list, canceling outstanding timeouts and free'ing data structures.
1955  */
1956 /* ARGSUSED */
1957 static void
1958 endpnt_destructor(zoneid_t zoneid, void *a)
1959 {
1960 	struct endpnt_type **npp;
1961 	struct endpnt_type *np;
1962 	struct endpnt_type *free_list = NULL;
1963 	timeout_id_t t_id = 0;
1964 	extern void clcleanup_zone(zoneid_t);
1965 	extern void clcleanup4_zone(zoneid_t);
1966 
1967 	/* Make sure NFS client handles are released. */
1968 	clcleanup_zone(zoneid);
1969 	clcleanup4_zone(zoneid);
1970 
1971 	endpnt_reclaim(zoneid);
1972 	/*
1973 	 * We don't need to be holding on to any locks across the call to
1974 	 * endpnt_reclaim() and the code below; we know that no-one can
1975 	 * be holding open connections for this zone (all processes and kernel
1976 	 * threads are gone), so nothing could be adding anything to the list.
1977 	 */
1978 	rw_enter(&endpnt_type_lock, RW_WRITER);
1979 	npp = &endpnt_type_list;
1980 	while ((np = *npp) != NULL) {
1981 		if (np->e_zoneid != zoneid) {
1982 			npp = &np->e_next;
1983 			continue;
1984 		}
1985 		mutex_enter(&np->e_plock);
1986 		mutex_enter(&np->e_ilock);
1987 		if (np->e_itimer != 0) {
1988 			t_id = np->e_itimer;
1989 			np->e_itimer = 0;
1990 		}
1991 		ASSERT(np->e_cnt == 0);
1992 		ASSERT(list_head(&np->e_pool) == NULL);
1993 		ASSERT(list_head(&np->e_ilist) == NULL);
1994 
1995 		mutex_exit(&np->e_ilock);
1996 		mutex_exit(&np->e_plock);
1997 
1998 		/*
1999 		 * untimeout() any outstanding timers that have not yet fired.
2000 		 */
2001 		if (t_id != (timeout_id_t)0)
2002 			(void) untimeout(t_id);
2003 		*npp = np->e_next;
2004 		np->e_next = free_list;
2005 		free_list = np;
2006 	}
2007 	rw_exit(&endpnt_type_lock);
2008 
2009 	while (free_list != NULL) {
2010 		np = free_list;
2011 		free_list = free_list->e_next;
2012 		/*
2013 		 * Wait for threads in endpnt_taskq trying to reap endpnt_ts in
2014 		 * the endpnt_type_t.
2015 		 */
2016 		mutex_enter(&np->e_ilock);
2017 		while (np->e_async_count > 0)
2018 			cv_wait(&np->e_async_cv, &np->e_ilock);
2019 		cv_destroy(&np->e_async_cv);
2020 		mutex_destroy(&np->e_plock);
2021 		mutex_destroy(&np->e_ilock);
2022 		list_destroy(&np->e_pool);
2023 		list_destroy(&np->e_ilist);
2024 		kmem_free(np, sizeof (endpnt_type_t));
2025 	}
2026 }
2027 
2028 /*
2029  * Endpoint reclaim kmem callback routine.
2030  */
2031 /* ARGSUSED */
2032 static void
2033 endpnt_repossess(void *a)
2034 {
2035 	/*
2036 	 * Reclaim idle endpnt's from all zones.
2037 	 */
2038 	if (endpnt_taskq != NULL)
2039 		(void) taskq_dispatch(endpnt_taskq,
2040 		    (task_func_t *)endpnt_reclaim, (void *)ALL_ZONES,
2041 		    TQ_NOSLEEP);
2042 }
2043 
2044 /*
2045  * RPC request dispatch routine.  Constructs a datagram message and wraps it
2046  * around the RPC request to pass downstream.
2047  */
2048 static int
2049 clnt_clts_dispatch_send(queue_t *q, mblk_t *mp, struct netbuf *addr,
2050 			calllist_t *cp,	uint_t xid)
2051 {
2052 	mblk_t *bp;
2053 	int msgsz;
2054 	struct T_unitdata_req *udreq;
2055 
2056 	/*
2057 	 * Set up the call record.
2058 	 */
2059 	cp->call_wq = q;
2060 	cp->call_xid = xid;
2061 	cp->call_status = RPC_TIMEDOUT;
2062 	cp->call_notified = FALSE;
2063 	RPCLOG(64,
2064 		"clnt_clts_dispatch_send: putting xid 0x%x on "
2065 		"dispatch list\n", xid);
2066 	cp->call_hash = call_hash(xid, clnt_clts_hash_size);
2067 	cp->call_bucket = &clts_call_ht[cp->call_hash];
2068 	call_table_enter(cp);
2069 
2070 	/*
2071 	 * Construct the datagram
2072 	 */
2073 	msgsz = (int)TUNITDATAREQSZ;
2074 	while (!(bp = allocb(msgsz + addr->len, BPRI_LO))) {
2075 		if (strwaitbuf(msgsz + addr->len, BPRI_LO))
2076 			return (ENOSR);
2077 	}
2078 
2079 	udreq = (struct T_unitdata_req *)bp->b_wptr;
2080 	udreq->PRIM_type = T_UNITDATA_REQ;
2081 	udreq->DEST_length = addr->len;
2082 
2083 	if (addr->len) {
2084 		bcopy(addr->buf, bp->b_wptr + msgsz, addr->len);
2085 		udreq->DEST_offset = (t_scalar_t)msgsz;
2086 		msgsz += addr->len;
2087 	} else
2088 		udreq->DEST_offset = 0;
2089 	udreq->OPT_length = 0;
2090 	udreq->OPT_offset = 0;
2091 
2092 	bp->b_datap->db_type = M_PROTO;
2093 	bp->b_wptr += msgsz;
2094 
2095 	/*
2096 	 * Link the datagram header with the actual data
2097 	 */
2098 	linkb(bp, mp);
2099 
2100 	/*
2101 	 * Send downstream.
2102 	 */
2103 	put(cp->call_wq, bp);
2104 
2105 	return (0);
2106 }
2107 
2108 /*
2109  * RPC response delivery routine.  Deliver the response to the waiting
2110  * thread by matching the xid.
2111  */
2112 void
2113 clnt_clts_dispatch_notify(mblk_t *mp, int resp_off, zoneid_t zoneid)
2114 {
2115 	calllist_t *e = NULL;
2116 	call_table_t *chtp;
2117 	uint32_t xid;
2118 	uint_t hash;
2119 	unsigned char *hdr_offset;
2120 	mblk_t *resp;
2121 
2122 	/*
2123 	 * If the RPC response is not contained in the same mblk as the
2124 	 * datagram header, then move to the next mblk.
2125 	 */
2126 	hdr_offset = mp->b_rptr;
2127 	resp = mp;
2128 	if ((mp->b_wptr - (mp->b_rptr + resp_off)) == 0)
2129 		resp = mp->b_cont;
2130 	else
2131 		resp->b_rptr += resp_off;
2132 
2133 	ASSERT(resp != NULL);
2134 
2135 	if ((IS_P2ALIGNED(resp->b_rptr, sizeof (uint32_t))) &&
2136 	    (resp->b_wptr - resp->b_rptr) >= sizeof (xid))
2137 		xid = *((uint32_t *)resp->b_rptr);
2138 	else {
2139 		int i = 0;
2140 		unsigned char *p = (unsigned char *)&xid;
2141 		unsigned char *rptr;
2142 		mblk_t *tmp = resp;
2143 
2144 		/*
2145 		 * Copy the xid, byte-by-byte into xid.
2146 		 */
2147 		while (tmp) {
2148 			rptr = tmp->b_rptr;
2149 			while (rptr < tmp->b_wptr) {
2150 				*p++ = *rptr++;
2151 				if (++i >= sizeof (xid))
2152 					goto done_xid_copy;
2153 			}
2154 			tmp = tmp->b_cont;
2155 		}
2156 
2157 		/*
2158 		 * If we got here, we ran out of mblk space before the
2159 		 * xid could be copied.
2160 		 */
2161 		ASSERT(tmp == NULL && i < sizeof (xid));
2162 
2163 		RPCLOG0(1,
2164 			"clnt_dispatch_notify(clts): message less than "
2165 			"size of xid\n");
2166 
2167 		freemsg(mp);
2168 		return;
2169 	}
2170 
2171 done_xid_copy:
2172 
2173 	/*
2174 	 * Reset the read pointer back to the beginning of the protocol
2175 	 * header if we moved it.
2176 	 */
2177 	if (mp->b_rptr != hdr_offset)
2178 		mp->b_rptr = hdr_offset;
2179 
2180 	hash = call_hash(xid, clnt_clts_hash_size);
2181 	chtp = &clts_call_ht[hash];
2182 	/* call_table_find returns with the hash bucket locked */
2183 	call_table_find(chtp, xid, e);
2184 
2185 	if (e != NULL) {
2186 		mutex_enter(&e->call_lock);
2187 		/*
2188 		 * found thread waiting for this reply.
2189 		 */
2190 		if (e->call_reply) {
2191 			RPCLOG(8,
2192 				"clnt_dispatch_notify (clts): discarding old "
2193 				"reply for xid 0x%x\n",
2194 				xid);
2195 			freemsg(e->call_reply);
2196 		}
2197 		e->call_notified = TRUE;
2198 		e->call_reply = mp;
2199 		e->call_status = RPC_SUCCESS;
2200 		cv_signal(&e->call_cv);
2201 		mutex_exit(&e->call_lock);
2202 		mutex_exit(&chtp->ct_lock);
2203 	} else {
2204 		zone_t *zone;
2205 		struct rpcstat *rpcstat;
2206 
2207 		mutex_exit(&chtp->ct_lock);
2208 		RPCLOG(8, "clnt_dispatch_notify (clts): no caller for reply "
2209 			"0x%x\n", xid);
2210 		freemsg(mp);
2211 		/*
2212 		 * This is unfortunate, but we need to lookup the zone so we
2213 		 * can increment its "rcbadxids" counter.
2214 		 */
2215 		zone = zone_find_by_id(zoneid);
2216 		if (zone == NULL) {
2217 			/*
2218 			 * The zone went away...
2219 			 */
2220 			return;
2221 		}
2222 		rpcstat = zone_getspecific(rpcstat_zone_key, zone);
2223 		if (zone_status_get(zone) >= ZONE_IS_SHUTTING_DOWN) {
2224 			/*
2225 			 * Not interested
2226 			 */
2227 			zone_rele(zone);
2228 			return;
2229 		}
2230 		RCSTAT_INCR(rpcstat->rpc_clts_client, rcbadxids);
2231 		zone_rele(zone);
2232 	}
2233 }
2234 
2235 /*
2236  * Init routine.  Called when rpcmod is loaded.
2237  */
2238 void
2239 clnt_clts_init(void)
2240 {
2241 	endpnt_cache = kmem_cache_create("clnt_clts_endpnt_cache",
2242 	    sizeof (struct endpnt), 0, NULL, NULL, endpnt_repossess, NULL,
2243 	    NULL, 0);
2244 
2245 	rw_init(&endpnt_type_lock, NULL, RW_DEFAULT, NULL);
2246 
2247 	/*
2248 	 * Perform simple bounds checking to make sure that the setting is
2249 	 * reasonable
2250 	 */
2251 	if (clnt_clts_max_endpoints <= 0) {
2252 		if (clnt_clts_do_bindresvport)
2253 			clnt_clts_max_endpoints = RESERVED_PORTSPACE;
2254 		else
2255 			clnt_clts_max_endpoints = NONRESERVED_PORTSPACE;
2256 	}
2257 
2258 	if (clnt_clts_do_bindresvport &&
2259 	    clnt_clts_max_endpoints > RESERVED_PORTSPACE)
2260 		clnt_clts_max_endpoints = RESERVED_PORTSPACE;
2261 	else if (clnt_clts_max_endpoints > NONRESERVED_PORTSPACE)
2262 		clnt_clts_max_endpoints = NONRESERVED_PORTSPACE;
2263 
2264 	if (clnt_clts_hash_size < DEFAULT_MIN_HASH_SIZE)
2265 		clnt_clts_hash_size = DEFAULT_MIN_HASH_SIZE;
2266 
2267 	/*
2268 	 * Defer creating the taskq until rpcmod gets pushed.  If we are
2269 	 * in diskless boot mode, rpcmod will get loaded early even before
2270 	 * thread_create() is available.
2271 	 */
2272 	endpnt_taskq = NULL;
2273 	taskq_created = FALSE;
2274 	mutex_init(&endpnt_taskq_lock, NULL, MUTEX_DEFAULT, NULL);
2275 
2276 	if (clnt_clts_endpoint_reap_interval < DEFAULT_ENDPOINT_REAP_INTERVAL)
2277 		clnt_clts_endpoint_reap_interval =
2278 			DEFAULT_ENDPOINT_REAP_INTERVAL;
2279 
2280 	/*
2281 	 * Dispatch the taskq at an interval which is offset from the
2282 	 * interval that the endpoints should be reaped.
2283 	 */
2284 	clnt_clts_taskq_dispatch_interval =
2285 		(clnt_clts_endpoint_reap_interval + DEFAULT_INTERVAL_SHIFT)
2286 		* hz;
2287 
2288 	/*
2289 	 * Initialize the completion queue
2290 	 */
2291 	clts_call_ht = call_table_init(clnt_clts_hash_size);
2292 	/*
2293 	 * Initialize the zone destructor callback.
2294 	 */
2295 	zone_key_create(&endpnt_destructor_key, NULL, NULL, endpnt_destructor);
2296 }
2297 
2298 void
2299 clnt_clts_fini(void)
2300 {
2301 	(void) zone_key_delete(endpnt_destructor_key);
2302 }
2303