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      1 /*	$NetBSD: puffs_msgif.c,v 1.108 2025/02/01 22:53:00 andvar Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2005, 2006, 2007  Antti Kantee.  All Rights Reserved.
      5  *
      6  * Development of this software was supported by the
      7  * Google Summer of Code program and the Ulla Tuominen Foundation.
      8  * The Google SoC project was mentored by Bill Studenmund.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
     20  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     22  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 __KERNEL_RCSID(0, "$NetBSD: puffs_msgif.c,v 1.108 2025/02/01 22:53:00 andvar Exp $");
     34 
     35 #include <sys/param.h>
     36 #include <sys/kernel.h>
     37 #include <sys/atomic.h>
     38 #include <sys/kmem.h>
     39 #include <sys/kthread.h>
     40 #include <sys/lock.h>
     41 #include <sys/mount.h>
     42 #include <sys/namei.h>
     43 #include <sys/proc.h>
     44 #include <sys/vnode.h>
     45 #include <sys/atomic.h>
     46 #include <sys/compat_stub.h>
     47 
     48 #include <uvm/uvm.h>
     49 
     50 #include <dev/putter/putter_sys.h>
     51 
     52 #include <fs/puffs/puffs_msgif.h>
     53 #include <fs/puffs/puffs_sys.h>
     54 
     55 /*
     56  * waitq data structures
     57  */
     58 
     59 /*
     60  * While a request is going to userspace, park the caller within the
     61  * kernel.  This is the kernel counterpart of "struct puffs_req".
     62  */
     63 struct puffs_msgpark {
     64 	struct puffs_req	*park_preq;	/* req followed by buf	*/
     65 
     66 	size_t			park_copylen;	/* userspace copylength	*/
     67 	size_t			park_maxlen;	/* max size in comeback */
     68 
     69 	struct puffs_req	*park_creq;	/* non-compat preq	*/
     70 	size_t			park_creqlen;	/* non-compat preq len	*/
     71 
     72 	parkdone_fn		park_done;	/* "biodone" a'la puffs	*/
     73 	void			*park_donearg;
     74 
     75 	int			park_flags;
     76 	int			park_refcount;
     77 
     78 	kcondvar_t		park_cv;
     79 	kmutex_t		park_mtx;
     80 
     81 	TAILQ_ENTRY(puffs_msgpark) park_entries;
     82 };
     83 #define PARKFLAG_WAITERGONE	0x01
     84 #define PARKFLAG_DONE		0x02
     85 #define PARKFLAG_ONQUEUE1	0x04
     86 #define PARKFLAG_ONQUEUE2	0x08
     87 #define PARKFLAG_CALL		0x10
     88 #define PARKFLAG_WANTREPLY	0x20
     89 #define	PARKFLAG_HASERROR	0x40
     90 
     91 static pool_cache_t parkpc;
     92 #ifdef PUFFSDEBUG
     93 static int totalpark;
     94 #endif
     95 
     96 int puffs_sopreq_expire_timeout = PUFFS_SOPREQ_EXPIRE_TIMEOUT;
     97 
     98 static int
     99 makepark(void *arg, void *obj, int flags)
    100 {
    101 	struct puffs_msgpark *park = obj;
    102 
    103 	mutex_init(&park->park_mtx, MUTEX_DEFAULT, IPL_NONE);
    104 	cv_init(&park->park_cv, "puffsrpl");
    105 
    106 	return 0;
    107 }
    108 
    109 static void
    110 nukepark(void *arg, void *obj)
    111 {
    112 	struct puffs_msgpark *park = obj;
    113 
    114 	cv_destroy(&park->park_cv);
    115 	mutex_destroy(&park->park_mtx);
    116 }
    117 
    118 void
    119 puffs_msgif_init(void)
    120 {
    121 
    122 	parkpc = pool_cache_init(sizeof(struct puffs_msgpark), 0, 0, 0,
    123 	    "puffprkl", NULL, IPL_NONE, makepark, nukepark, NULL);
    124 }
    125 
    126 void
    127 puffs_msgif_destroy(void)
    128 {
    129 
    130 	pool_cache_destroy(parkpc);
    131 }
    132 
    133 static struct puffs_msgpark *
    134 puffs_msgpark_alloc(int waitok)
    135 {
    136 	struct puffs_msgpark *park;
    137 
    138 	KASSERT(curlwp != uvm.pagedaemon_lwp || !waitok);
    139 
    140 	park = pool_cache_get(parkpc, waitok ? PR_WAITOK : PR_NOWAIT);
    141 	if (park == NULL)
    142 		return park;
    143 
    144 	park->park_refcount = 1;
    145 	park->park_preq = park->park_creq = NULL;
    146 	park->park_flags = PARKFLAG_WANTREPLY;
    147 
    148 #ifdef PUFFSDEBUG
    149 	totalpark++;
    150 #endif
    151 
    152 	return park;
    153 }
    154 
    155 static void
    156 puffs_msgpark_reference(struct puffs_msgpark *park)
    157 {
    158 
    159 	KASSERT(mutex_owned(&park->park_mtx));
    160 	park->park_refcount++;
    161 }
    162 
    163 /*
    164  * Release reference to park structure.
    165  */
    166 static void
    167 puffs_msgpark_release1(struct puffs_msgpark *park, int howmany)
    168 {
    169 	struct puffs_req *preq = park->park_preq;
    170 	struct puffs_req *creq = park->park_creq;
    171 	int refcnt;
    172 
    173 	KASSERT(mutex_owned(&park->park_mtx));
    174 	refcnt = park->park_refcount -= howmany;
    175 	mutex_exit(&park->park_mtx);
    176 
    177 	KASSERT(refcnt >= 0);
    178 
    179 	if (refcnt == 0) {
    180 		if (preq)
    181 			kmem_free(preq, park->park_maxlen);
    182 #if 1
    183 		if (creq)
    184 			kmem_free(creq, park->park_creqlen);
    185 #endif
    186 		pool_cache_put(parkpc, park);
    187 
    188 #ifdef PUFFSDEBUG
    189 		totalpark--;
    190 #endif
    191 	}
    192 }
    193 #define puffs_msgpark_release(a) puffs_msgpark_release1(a, 1)
    194 
    195 #ifdef PUFFSDEBUG
    196 static void
    197 parkdump(struct puffs_msgpark *park)
    198 {
    199 
    200 	DPRINTF(("park %p, preq %p, id %" PRIu64 "\n"
    201 	    "\tcopy %zu, max %zu - done: %p/%p\n"
    202 	    "\tflags 0x%08x, refcount %d, cv/mtx: %p/%p\n",
    203 	    park, park->park_preq, park->park_preq->preq_id,
    204 	    park->park_copylen, park->park_maxlen,
    205 	    park->park_done, park->park_donearg,
    206 	    park->park_flags, park->park_refcount,
    207 	    &park->park_cv, &park->park_mtx));
    208 }
    209 
    210 static void
    211 parkqdump(struct puffs_wq *q, int dumpall)
    212 {
    213 	struct puffs_msgpark *park;
    214 	int total = 0;
    215 
    216 	TAILQ_FOREACH(park, q, park_entries) {
    217 		if (dumpall)
    218 			parkdump(park);
    219 		total++;
    220 	}
    221 	DPRINTF(("puffs waitqueue at %p dumped, %d total\n", q, total));
    222 
    223 }
    224 #endif /* PUFFSDEBUG */
    225 
    226 /*
    227  * A word about locking in the park structures: the lock protects the
    228  * fields of the *park* structure (not preq) and acts as an interlock
    229  * in cv operations.  The lock is always internal to this module and
    230  * callers do not need to worry about it.
    231  */
    232 
    233 int
    234 puffs_msgmem_alloc(size_t len, struct puffs_msgpark **ppark, void **mem,
    235 	int cansleep)
    236 {
    237 	struct puffs_msgpark *park;
    238 	void *m;
    239 
    240 	KASSERT(curlwp != uvm.pagedaemon_lwp || !cansleep);
    241 	m = kmem_zalloc(len, cansleep ? KM_SLEEP : KM_NOSLEEP);
    242 	if (m == NULL) {
    243 		KASSERT(cansleep == 0);
    244 		return ENOMEM;
    245 	}
    246 
    247 	park = puffs_msgpark_alloc(cansleep);
    248 	if (park == NULL) {
    249 		KASSERT(cansleep == 0);
    250 		kmem_free(m, len);
    251 		return ENOMEM;
    252 	}
    253 
    254 	park->park_preq = m;
    255 	park->park_maxlen = park->park_copylen = len;
    256 
    257 	*ppark = park;
    258 	*mem = m;
    259 
    260 	return 0;
    261 }
    262 
    263 void
    264 puffs_msgmem_release(struct puffs_msgpark *park)
    265 {
    266 
    267 	if (park == NULL)
    268 		return;
    269 
    270 	mutex_enter(&park->park_mtx);
    271 	puffs_msgpark_release(park);
    272 }
    273 
    274 void
    275 puffs_msg_setfaf(struct puffs_msgpark *park)
    276 {
    277 
    278 	KASSERT((park->park_flags & PARKFLAG_CALL) == 0);
    279 	park->park_flags &= ~PARKFLAG_WANTREPLY;
    280 }
    281 
    282 void
    283 puffs_msg_setdelta(struct puffs_msgpark *park, size_t delta)
    284 {
    285 
    286 	KASSERT(delta < park->park_maxlen); /* "<=" wouldn't make sense */
    287 	park->park_copylen = park->park_maxlen - delta;
    288 }
    289 
    290 void
    291 puffs_msg_setinfo(struct puffs_msgpark *park, int opclass, int type,
    292 	puffs_cookie_t ck)
    293 {
    294 
    295 	park->park_preq->preq_opclass = PUFFSOP_OPCLASS(opclass);
    296 	park->park_preq->preq_optype = type;
    297 	park->park_preq->preq_cookie = ck;
    298 }
    299 
    300 void
    301 puffs_msg_setcall(struct puffs_msgpark *park, parkdone_fn donefn, void *donearg)
    302 {
    303 
    304 	KASSERT(park->park_flags & PARKFLAG_WANTREPLY);
    305 	park->park_done = donefn;
    306 	park->park_donearg = donearg;
    307 	park->park_flags |= PARKFLAG_CALL;
    308 }
    309 
    310 /*
    311  * kernel-user-kernel waitqueues
    312  */
    313 
    314 static uint64_t
    315 puffs_getmsgid(struct puffs_mount *pmp)
    316 {
    317 	uint64_t rv;
    318 
    319 	mutex_enter(&pmp->pmp_lock);
    320 	rv = pmp->pmp_nextmsgid++;
    321 	mutex_exit(&pmp->pmp_lock);
    322 
    323 	return rv;
    324 }
    325 
    326 /*
    327  * A word about reference counting of parks.  A reference must be taken
    328  * when accessing a park and additionally when it is on a queue.  So
    329  * when taking it off a queue and releasing the access reference, the
    330  * reference count is generally decremented by 2.
    331  */
    332 
    333 void
    334 puffs_msg_enqueue(struct puffs_mount *pmp, struct puffs_msgpark *park)
    335 {
    336 	struct lwp *l = curlwp;
    337 	struct puffs_req *preq, *creq;
    338 	ssize_t delta;
    339 #if 1
    340 	int ret;
    341 #endif
    342 
    343 	/*
    344 	 * Some clients reuse a park, so reset some flags.  We might
    345 	 * want to provide a caller-side interface for this and add
    346 	 * a few more invariant checks here, but this will do for now.
    347 	 */
    348 	park->park_flags &= ~(PARKFLAG_DONE | PARKFLAG_HASERROR);
    349 	KASSERT((park->park_flags & PARKFLAG_WAITERGONE) == 0);
    350 
    351 	preq = park->park_preq;
    352 
    353 #if 1
    354 	/* check if we do compat adjustments */
    355 	if (pmp->pmp_docompat) {
    356 		MODULE_HOOK_CALL(puffs_out_50_hook, (preq, &creq, &delta),
    357 		    enosys(), ret);
    358 		if (ret == 0) {
    359 			park->park_creq = park->park_preq;
    360 			park->park_creqlen = park->park_maxlen;
    361 
    362 			park->park_maxlen += delta;
    363 			park->park_copylen += delta;
    364 			park->park_preq = preq = creq;
    365 		}
    366 	}
    367 #endif
    368 
    369 	preq->preq_buflen = park->park_maxlen;
    370 	KASSERT(preq->preq_id == 0
    371 	    || (preq->preq_opclass & PUFFSOPFLAG_ISRESPONSE));
    372 
    373 	if ((park->park_flags & PARKFLAG_WANTREPLY) == 0)
    374 		preq->preq_opclass |= PUFFSOPFLAG_FAF;
    375 	else
    376 		preq->preq_id = puffs_getmsgid(pmp);
    377 
    378 	/* fill in caller information */
    379 	preq->preq_pid = l->l_proc->p_pid;
    380 	preq->preq_lid = l->l_lid;
    381 
    382 	/*
    383 	 * To support cv_sig, yet another movie: check if there are signals
    384 	 * pending and we are issuing a non-FAF.  If so, return an error
    385 	 * directly UNLESS we are issuing INACTIVE/RECLAIM.  In that case,
    386 	 * convert it to a FAF, fire off to the file server and return
    387 	 * an error.  Yes, this is bordering disgusting.  Barfbags are on me.
    388 	 */
    389 	if (__predict_false((park->park_flags & PARKFLAG_WANTREPLY)
    390 	   && (park->park_flags & PARKFLAG_CALL) == 0
    391 	   && (l->l_flag & LW_PENDSIG) != 0 && sigispending(l, 0))) {
    392 		sigset_t ss;
    393 
    394 		/*
    395 		 * see the comment about signals in puffs_msg_wait.
    396 		 */
    397 		sigpending1(l, &ss);
    398 		if (sigismember(&ss, SIGINT) ||
    399 		    sigismember(&ss, SIGTERM) ||
    400 		    sigismember(&ss, SIGKILL) ||
    401 		    sigismember(&ss, SIGHUP) ||
    402 		    sigismember(&ss, SIGQUIT)) {
    403 			park->park_flags |= PARKFLAG_HASERROR;
    404 			preq->preq_rv = EINTR;
    405 			if (PUFFSOP_OPCLASS(preq->preq_opclass) == PUFFSOP_VN
    406 			    && (preq->preq_optype == PUFFS_VN_INACTIVE
    407 			     || preq->preq_optype == PUFFS_VN_RECLAIM)) {
    408 				park->park_preq->preq_opclass |=
    409 				    PUFFSOPFLAG_FAF;
    410 				park->park_flags &= ~PARKFLAG_WANTREPLY;
    411 				DPRINTF(("puffs_msg_enqueue: "
    412 				    "converted to FAF %p\n", park));
    413 			} else {
    414 				return;
    415 			}
    416 		}
    417 	}
    418 
    419 	mutex_enter(&pmp->pmp_lock);
    420 	if (pmp->pmp_status != PUFFSTAT_RUNNING) {
    421 		mutex_exit(&pmp->pmp_lock);
    422 		park->park_flags |= PARKFLAG_HASERROR;
    423 		preq->preq_rv = ENXIO;
    424 		return;
    425 	}
    426 
    427 #ifdef PUFFSDEBUG
    428 	parkqdump(&pmp->pmp_msg_touser, puffsdebug > 1);
    429 	parkqdump(&pmp->pmp_msg_replywait, puffsdebug > 1);
    430 #endif
    431 
    432 	/*
    433 	 * Note: we don't need to lock park since we have the only
    434 	 * reference to it at this point.
    435 	 */
    436 	TAILQ_INSERT_TAIL(&pmp->pmp_msg_touser, park, park_entries);
    437 	park->park_flags |= PARKFLAG_ONQUEUE1;
    438 	pmp->pmp_msg_touser_count++;
    439 	park->park_refcount++;
    440 
    441 	cv_broadcast(&pmp->pmp_msg_waiter_cv);
    442 	mutex_exit(&pmp->pmp_lock);
    443 	putter_notify(pmp->pmp_pi);
    444 
    445 	DPRINTF(("touser: req %" PRIu64 ", preq: %p, park: %p, "
    446 	    "c/t: 0x%x/0x%x, f: 0x%x\n", preq->preq_id, preq, park,
    447 	    preq->preq_opclass, preq->preq_optype, park->park_flags));
    448 }
    449 
    450 int
    451 puffs_msg_wait(struct puffs_mount *pmp, struct puffs_msgpark *park)
    452 {
    453 	lwp_t *l = curlwp;
    454 	proc_t *p = l->l_proc;
    455 	struct puffs_req *preq = park->park_preq; /* XXX: hmmm */
    456 	sigset_t ss;
    457 	sigset_t oss;
    458 	int error = 0;
    459 	int rv;
    460 
    461 	/*
    462 	 * block unimportant signals.
    463 	 *
    464 	 * The set of "important" signals here was chosen to be same as
    465 	 * nfs interruptible mount.
    466 	 */
    467 	sigfillset(&ss);
    468 	sigdelset(&ss, SIGINT);
    469 	sigdelset(&ss, SIGTERM);
    470 	sigdelset(&ss, SIGKILL);
    471 	sigdelset(&ss, SIGHUP);
    472 	sigdelset(&ss, SIGQUIT);
    473 	mutex_enter(p->p_lock);
    474 	sigprocmask1(l, SIG_BLOCK, &ss, &oss);
    475 	mutex_exit(p->p_lock);
    476 
    477 	mutex_enter(&pmp->pmp_lock);
    478 	puffs_mp_reference(pmp);
    479 	mutex_exit(&pmp->pmp_lock);
    480 
    481 	mutex_enter(&park->park_mtx);
    482 	/* did the response beat us to the wait? */
    483 	if (__predict_false((park->park_flags & PARKFLAG_DONE)
    484 	    || (park->park_flags & PARKFLAG_HASERROR))) {
    485 		rv = park->park_preq->preq_rv;
    486 		mutex_exit(&park->park_mtx);
    487 		goto skipwait;
    488 	}
    489 
    490 	if ((park->park_flags & PARKFLAG_WANTREPLY) == 0
    491 	    || (park->park_flags & PARKFLAG_CALL)) {
    492 		mutex_exit(&park->park_mtx);
    493 		rv = 0;
    494 		goto skipwait;
    495 	}
    496 
    497 	error = cv_wait_sig(&park->park_cv, &park->park_mtx);
    498 	DPRINTF(("puffs_touser: waiter for %p woke up with %d\n",
    499 	    park, error));
    500 	if (error) {
    501 		park->park_flags |= PARKFLAG_WAITERGONE;
    502 		if (park->park_flags & PARKFLAG_DONE) {
    503 			rv = preq->preq_rv;
    504 			mutex_exit(&park->park_mtx);
    505 		} else {
    506 			/*
    507 			 * ok, we marked it as going away, but
    508 			 * still need to do queue ops.  take locks
    509 			 * in correct order.
    510 			 *
    511 			 * We don't want to release our reference
    512 			 * if it's on replywait queue to avoid error
    513 			 * to file server.  putop() code will DTRT.
    514 			 */
    515 			mutex_exit(&park->park_mtx);
    516 			mutex_enter(&pmp->pmp_lock);
    517 			mutex_enter(&park->park_mtx);
    518 
    519 			/*
    520 			 * Still on queue1?  We can safely remove it
    521 			 * without any consequences since the file
    522 			 * server hasn't seen it.  "else" we need to
    523 			 * wait for the response and just ignore it
    524 			 * to avoid signalling an incorrect error to
    525 			 * the file server.
    526 			 */
    527 			if (park->park_flags & PARKFLAG_ONQUEUE1) {
    528 				TAILQ_REMOVE(&pmp->pmp_msg_touser,
    529 				    park, park_entries);
    530 				puffs_msgpark_release(park);
    531 				pmp->pmp_msg_touser_count--;
    532 				park->park_flags &= ~PARKFLAG_ONQUEUE1;
    533 			} else {
    534 				mutex_exit(&park->park_mtx);
    535 			}
    536 			mutex_exit(&pmp->pmp_lock);
    537 
    538 			rv = EINTR;
    539 		}
    540 	} else {
    541 		rv = preq->preq_rv;
    542 		mutex_exit(&park->park_mtx);
    543 	}
    544 
    545  skipwait:
    546 	mutex_enter(&pmp->pmp_lock);
    547 	puffs_mp_release(pmp);
    548 	mutex_exit(&pmp->pmp_lock);
    549 
    550 	mutex_enter(p->p_lock);
    551 	sigprocmask1(l, SIG_SETMASK, &oss, NULL);
    552 	mutex_exit(p->p_lock);
    553 
    554 	return rv;
    555 }
    556 
    557 /*
    558  * XXX: this suuuucks.  Hopefully I'll get rid of this lossage once
    559  * the whole setback-nonsense gets fixed.
    560  */
    561 int
    562 puffs_msg_wait2(struct puffs_mount *pmp, struct puffs_msgpark *park,
    563 	struct puffs_node *pn1, struct puffs_node *pn2)
    564 {
    565 	struct puffs_req *preq;
    566 	int rv;
    567 
    568 	rv = puffs_msg_wait(pmp, park);
    569 
    570 	preq = park->park_preq;
    571 	if (pn1 && preq->preq_setbacks & PUFFS_SETBACK_INACT_N1)
    572 		pn1->pn_stat |= PNODE_DOINACT;
    573 	if (pn2 && preq->preq_setbacks & PUFFS_SETBACK_INACT_N2)
    574 		pn2->pn_stat |= PNODE_DOINACT;
    575 
    576 	if (pn1 && preq->preq_setbacks & PUFFS_SETBACK_NOREF_N1)
    577 		pn1->pn_stat |= PNODE_NOREFS;
    578 	if (pn2 && preq->preq_setbacks & PUFFS_SETBACK_NOREF_N2)
    579 		pn2->pn_stat |= PNODE_NOREFS;
    580 
    581 	return rv;
    582 
    583 }
    584 
    585 /*
    586  * XXX: lazy bum.  please, for the love of foie gras, fix me.
    587  * This should *NOT* depend on setfaf.  Also "memcpy" could
    588  * be done more nicely.
    589  */
    590 void
    591 puffs_msg_sendresp(struct puffs_mount *pmp, struct puffs_req *origpreq, int rv)
    592 {
    593 	struct puffs_msgpark *park;
    594 	struct puffs_req *preq;
    595 
    596 	puffs_msgmem_alloc(sizeof(struct puffs_req), &park, (void *)&preq, 1);
    597 	puffs_msg_setfaf(park); /* XXXXXX: avoids reqid override */
    598 
    599 	memcpy(preq, origpreq, sizeof(struct puffs_req));
    600 	preq->preq_rv = rv;
    601 	preq->preq_opclass |= PUFFSOPFLAG_ISRESPONSE;
    602 
    603 	puffs_msg_enqueue(pmp, park);
    604 	puffs_msgmem_release(park);
    605 }
    606 
    607 /*
    608  * Get next request in the outgoing queue.  "maxsize" controls the
    609  * size the caller can accommodate and "nonblock" signals if this
    610  * should block while waiting for input.  Handles all locking internally.
    611  */
    612 int
    613 puffs_msgif_getout(void *ctx, size_t maxsize, int nonblock,
    614 	uint8_t **data, size_t *dlen, void **parkptr)
    615 {
    616 	struct puffs_mount *pmp = ctx;
    617 	struct puffs_msgpark *park = NULL;
    618 	struct puffs_req *preq = NULL;
    619 	int error;
    620 
    621 	error = 0;
    622 	mutex_enter(&pmp->pmp_lock);
    623 	puffs_mp_reference(pmp);
    624 	for (;;) {
    625 		/* RIP? */
    626 		if (pmp->pmp_status != PUFFSTAT_RUNNING) {
    627 			error = ENXIO;
    628 			break;
    629 		}
    630 
    631 		/* need platinum yendorian express card? */
    632 		if (TAILQ_EMPTY(&pmp->pmp_msg_touser)) {
    633 			DPRINTF(("puffs_getout: no outgoing op, "));
    634 			if (nonblock) {
    635 				DPRINTF(("returning EWOULDBLOCK\n"));
    636 				error = EWOULDBLOCK;
    637 				break;
    638 			}
    639 			DPRINTF(("waiting ...\n"));
    640 
    641 			error = cv_wait_sig(&pmp->pmp_msg_waiter_cv,
    642 			    &pmp->pmp_lock);
    643 			if (error)
    644 				break;
    645 			else
    646 				continue;
    647 		}
    648 
    649 		park = TAILQ_FIRST(&pmp->pmp_msg_touser);
    650 		if (park == NULL)
    651 			continue;
    652 
    653 		mutex_enter(&park->park_mtx);
    654 		puffs_msgpark_reference(park);
    655 
    656 		DPRINTF(("puffs_getout: found park at %p, ", park));
    657 
    658 		/* If it's a goner, don't process any further */
    659 		if (park->park_flags & PARKFLAG_WAITERGONE) {
    660 			DPRINTF(("waitergone!\n"));
    661 			puffs_msgpark_release(park);
    662 			continue;
    663 		}
    664 		preq = park->park_preq;
    665 
    666 #if 0
    667 		/* check size */
    668 		/*
    669 		 * XXX: this check is not valid for now, we don't know
    670 		 * the size of the caller's input buffer.  i.e. this
    671 		 * will most likely go away
    672 		 */
    673 		if (maxsize < preq->preq_frhdr.pfr_len) {
    674 			DPRINTF(("buffer too small\n"));
    675 			puffs_msgpark_release(park);
    676 			error = E2BIG;
    677 			break;
    678 		}
    679 #endif
    680 
    681 		DPRINTF(("returning\n"));
    682 
    683 		/*
    684 		 * Ok, we found what we came for.  Release it from the
    685 		 * outgoing queue but do not unlock.  We will unlock
    686 		 * only after we "releaseout" it to avoid complications:
    687 		 * otherwise it is (theoretically) possible for userland
    688 		 * to race us into "put" before we have a change to put
    689 		 * this baby on the receiving queue.
    690 		 */
    691 		TAILQ_REMOVE(&pmp->pmp_msg_touser, park, park_entries);
    692 		KASSERT(park->park_flags & PARKFLAG_ONQUEUE1);
    693 		park->park_flags &= ~PARKFLAG_ONQUEUE1;
    694 		mutex_exit(&park->park_mtx);
    695 
    696 		pmp->pmp_msg_touser_count--;
    697 		KASSERT(pmp->pmp_msg_touser_count >= 0);
    698 
    699 		break;
    700 	}
    701 	puffs_mp_release(pmp);
    702 	mutex_exit(&pmp->pmp_lock);
    703 
    704 	if (error == 0) {
    705 		*data = (uint8_t *)preq;
    706 		preq->preq_pth.pth_framelen = park->park_copylen;
    707 		*dlen = preq->preq_pth.pth_framelen;
    708 		*parkptr = park;
    709 	}
    710 
    711 	return error;
    712 }
    713 
    714 /*
    715  * Release outgoing structure.  Now, depending on the success of the
    716  * outgoing send, it is either going onto the result waiting queue
    717  * or the death chamber.
    718  */
    719 void
    720 puffs_msgif_releaseout(void *ctx, void *parkptr, int status)
    721 {
    722 	struct puffs_mount *pmp = ctx;
    723 	struct puffs_msgpark *park = parkptr;
    724 
    725 	DPRINTF(("puffs_releaseout: returning park %p, errno %d: " ,
    726 	    park, status));
    727 	mutex_enter(&pmp->pmp_lock);
    728 	mutex_enter(&park->park_mtx);
    729 	if (park->park_flags & PARKFLAG_WANTREPLY) {
    730 		if (status == 0) {
    731 			DPRINTF(("enqueue replywait\n"));
    732 			TAILQ_INSERT_TAIL(&pmp->pmp_msg_replywait, park,
    733 			    park_entries);
    734 			park->park_flags |= PARKFLAG_ONQUEUE2;
    735 		} else {
    736 			DPRINTF(("error path!\n"));
    737 			park->park_preq->preq_rv = status;
    738 			park->park_flags |= PARKFLAG_DONE;
    739 			cv_signal(&park->park_cv);
    740 		}
    741 		puffs_msgpark_release(park);
    742 	} else {
    743 		DPRINTF(("release\n"));
    744 		puffs_msgpark_release1(park, 2);
    745 	}
    746 	mutex_exit(&pmp->pmp_lock);
    747 }
    748 
    749 size_t
    750 puffs_msgif_waitcount(void *ctx)
    751 {
    752 	struct puffs_mount *pmp = ctx;
    753 	size_t rv;
    754 
    755 	mutex_enter(&pmp->pmp_lock);
    756 	rv = pmp->pmp_msg_touser_count;
    757 	mutex_exit(&pmp->pmp_lock);
    758 
    759 	return rv;
    760 }
    761 
    762 /*
    763  * XXX: locking with this one?
    764  */
    765 static void
    766 puffsop_msg(void *ctx, struct puffs_req *preq)
    767 {
    768 	struct puffs_mount *pmp = ctx;
    769 	struct putter_hdr *pth = &preq->preq_pth;
    770 	struct puffs_msgpark *park;
    771 	int wgone;
    772 
    773 	mutex_enter(&pmp->pmp_lock);
    774 
    775 	/* Locate waiter */
    776 	TAILQ_FOREACH(park, &pmp->pmp_msg_replywait, park_entries) {
    777 		if (park->park_preq->preq_id == preq->preq_id)
    778 			break;
    779 	}
    780 	if (park == NULL) {
    781 		DPRINTF(("puffsop_msg: no request: %" PRIu64 "\n",
    782 		    preq->preq_id));
    783 		mutex_exit(&pmp->pmp_lock);
    784 		return; /* XXX send error */
    785 	}
    786 
    787 	mutex_enter(&park->park_mtx);
    788 	puffs_msgpark_reference(park);
    789 	if (pth->pth_framelen > park->park_maxlen) {
    790 		DPRINTF(("puffsop_msg: invalid buffer length: "
    791 		    "%" PRIu64 " (req %" PRIu64 ", \n", pth->pth_framelen,
    792 		    preq->preq_id));
    793 		park->park_preq->preq_rv = EPROTO;
    794 		cv_signal(&park->park_cv);
    795 		puffs_msgpark_release1(park, 2);
    796 		mutex_exit(&pmp->pmp_lock);
    797 		return; /* XXX: error */
    798 	}
    799 	wgone = park->park_flags & PARKFLAG_WAITERGONE;
    800 
    801 	KASSERT(park->park_flags & PARKFLAG_ONQUEUE2);
    802 	TAILQ_REMOVE(&pmp->pmp_msg_replywait, park, park_entries);
    803 	park->park_flags &= ~PARKFLAG_ONQUEUE2;
    804 	mutex_exit(&pmp->pmp_lock);
    805 
    806 	if (wgone) {
    807 		DPRINTF(("puffsop_msg: bad service - waiter gone for "
    808 		    "park %p\n", park));
    809 	} else {
    810 #if 1
    811 		if (park->park_creq) {
    812 			struct puffs_req *creq;
    813 			size_t csize;
    814 
    815 			KASSERT(pmp->pmp_docompat);
    816 			MODULE_HOOK_CALL_VOID(puffs_in_50_hook,
    817 			     (preq, park->park_creq), __nothing);
    818 			creq = park->park_creq;
    819 			csize = park->park_creqlen;
    820 			park->park_creq = park->park_preq;
    821 			park->park_creqlen = park->park_maxlen;
    822 
    823 			park->park_preq = creq;
    824 			park->park_maxlen = csize;
    825 
    826 			memcpy(park->park_creq, preq, pth->pth_framelen);
    827 		} else {
    828 #endif
    829 			memcpy(park->park_preq, preq, pth->pth_framelen);
    830 		}
    831 
    832 		if (park->park_flags & PARKFLAG_CALL) {
    833 			DPRINTF(("puffsop_msg: call for %p, arg %p\n",
    834 			    park->park_preq, park->park_donearg));
    835 			park->park_done(pmp, preq, park->park_donearg);
    836 		}
    837 	}
    838 
    839 	if (!wgone) {
    840 		DPRINTF(("puffs_putop: flagging done for "
    841 		    "park %p\n", park));
    842 		cv_signal(&park->park_cv);
    843 	}
    844 
    845 	park->park_flags |= PARKFLAG_DONE;
    846 	puffs_msgpark_release1(park, 2);
    847 }
    848 
    849 /*
    850  * Node expiry. We come here after an inactive on an unexpired node.
    851  * The expiry has been queued and is done in sop thread.
    852  */
    853 static void
    854 puffsop_expire(struct puffs_mount *pmp, puffs_cookie_t cookie)
    855 {
    856 	struct vnode *vp;
    857 
    858 	KASSERT(PUFFS_USE_FS_TTL(pmp));
    859 
    860 	/*
    861 	 * If it still exists and has no reference,
    862 	 * vrele should cause it to be reclaimed.
    863 	 * Otherwise, we have nothing to do.
    864 	 */
    865 	if (puffs_cookie2vnode(pmp, cookie, &vp) == 0) {
    866 		VPTOPP(vp)->pn_stat &= ~PNODE_SOPEXP;
    867 		vrele(vp);
    868 	}
    869 
    870 	return;
    871 }
    872 
    873 static void
    874 puffsop_flush(struct puffs_mount *pmp, struct puffs_flush *pf)
    875 {
    876 	struct vnode *vp;
    877 	voff_t offlo, offhi;
    878 	int rv, flags = 0;
    879 
    880 	KASSERT(pf->pf_req.preq_pth.pth_framelen == sizeof(struct puffs_flush));
    881 
    882 	/* XXX: slurry */
    883 	if (pf->pf_op == PUFFS_INVAL_NAMECACHE_ALL) {
    884 		cache_purgevfs(PMPTOMP(pmp));
    885 		rv = 0;
    886 		goto out;
    887 	}
    888 
    889 	/*
    890 	 * Get vnode, don't lock it.  Namecache is protected by its own lock
    891 	 * and we have a reference to protect against premature harvesting.
    892 	 *
    893 	 * The node we want here might be locked and the op is in
    894 	 * userspace waiting for us to complete ==> deadlock.  Another
    895 	 * reason we need to eventually bump locking to userspace, as we
    896 	 * will need to lock the node if we wish to do flushes.
    897 	 */
    898 	rv = puffs_cookie2vnode(pmp, pf->pf_cookie, &vp);
    899 	if (rv) {
    900 		if (rv == PUFFS_NOSUCHCOOKIE)
    901 			rv = ENOENT;
    902 		goto out;
    903 	}
    904 
    905 	switch (pf->pf_op) {
    906 #if 0
    907 	/* not quite ready, yet */
    908 	case PUFFS_INVAL_NAMECACHE_NODE:
    909 	struct componentname *pf_cn;
    910 	char *name;
    911 		/* get comfortab^Wcomponentname */
    912 		pf_cn = kmem_alloc(componentname);
    913 		memset(pf_cn, 0, sizeof(struct componentname));
    914 		break;
    915 
    916 #endif
    917 	case PUFFS_INVAL_NAMECACHE_DIR:
    918 		if (vp->v_type != VDIR) {
    919 			rv = EINVAL;
    920 			break;
    921 		}
    922 		cache_purge1(vp, NULL, 0, PURGE_CHILDREN);
    923 		break;
    924 
    925 	case PUFFS_INVAL_PAGECACHE_NODE_RANGE:
    926 		flags = PGO_FREE;
    927 		/*FALLTHROUGH*/
    928 	case PUFFS_FLUSH_PAGECACHE_NODE_RANGE:
    929 		if (flags == 0)
    930 			flags = PGO_CLEANIT;
    931 
    932 		if (pf->pf_end > vp->v_size || vp->v_type != VREG) {
    933 			rv = EINVAL;
    934 			break;
    935 		}
    936 
    937 		offlo = trunc_page(pf->pf_start);
    938 		offhi = round_page(pf->pf_end);
    939 		if (offhi != 0 && offlo >= offhi) {
    940 			rv = EINVAL;
    941 			break;
    942 		}
    943 
    944 		rw_enter(vp->v_uobj.vmobjlock, RW_WRITER);
    945 		rv = VOP_PUTPAGES(vp, offlo, offhi, flags);
    946 		break;
    947 
    948 	default:
    949 		rv = EINVAL;
    950 	}
    951 
    952 	vrele(vp);
    953 
    954  out:
    955 	puffs_msg_sendresp(pmp, &pf->pf_req, rv);
    956 }
    957 
    958 int
    959 puffs_msgif_dispatch(void *ctx, struct putter_hdr *pth)
    960 {
    961 	struct puffs_mount *pmp = ctx;
    962 	struct puffs_req *preq = (struct puffs_req *)pth;
    963 	struct puffs_sopreq *psopr;
    964 
    965 	if (pth->pth_framelen < sizeof(struct puffs_req)) {
    966 		puffs_msg_sendresp(pmp, preq, EINVAL); /* E2SMALL */
    967 		return 0;
    968 	}
    969 
    970 	switch (PUFFSOP_OPCLASS(preq->preq_opclass)) {
    971 	case PUFFSOP_VN:
    972 	case PUFFSOP_VFS:
    973 		DPRINTF(("dispatch: vn/vfs message 0x%x\n", preq->preq_optype));
    974 		puffsop_msg(pmp, preq);
    975 		break;
    976 
    977 	case PUFFSOP_FLUSH: /* process in sop thread */
    978 	{
    979 		struct puffs_flush *pf;
    980 
    981 		DPRINTF(("dispatch: flush 0x%x\n", preq->preq_optype));
    982 
    983 		if (preq->preq_pth.pth_framelen != sizeof(struct puffs_flush)) {
    984 			puffs_msg_sendresp(pmp, preq, EINVAL); /* E2SMALL */
    985 			break;
    986 		}
    987 		pf = (struct puffs_flush *)preq;
    988 
    989 		KASSERT(curlwp != uvm.pagedaemon_lwp);
    990 		psopr = kmem_alloc(sizeof(*psopr), KM_SLEEP);
    991 		memcpy(&psopr->psopr_pf, pf, sizeof(*pf));
    992 		psopr->psopr_sopreq = PUFFS_SOPREQ_FLUSH;
    993 
    994 		mutex_enter(&pmp->pmp_sopmtx);
    995 		if (pmp->pmp_sopthrcount == 0) {
    996 			mutex_exit(&pmp->pmp_sopmtx);
    997 			kmem_free(psopr, sizeof(*psopr));
    998 			puffs_msg_sendresp(pmp, preq, ENXIO);
    999 		} else {
   1000 			TAILQ_INSERT_TAIL(&pmp->pmp_sopfastreqs,
   1001 			    psopr, psopr_entries);
   1002 			cv_signal(&pmp->pmp_sopcv);
   1003 			mutex_exit(&pmp->pmp_sopmtx);
   1004 		}
   1005 		break;
   1006 	}
   1007 
   1008 	case PUFFSOP_UNMOUNT: /* process in sop thread */
   1009 	{
   1010 
   1011 		DPRINTF(("dispatch: unmount 0x%x\n", preq->preq_optype));
   1012 
   1013 		KASSERT(curlwp != uvm.pagedaemon_lwp);
   1014 		psopr = kmem_alloc(sizeof(*psopr), KM_SLEEP);
   1015 		psopr->psopr_preq = *preq;
   1016 		psopr->psopr_sopreq = PUFFS_SOPREQ_UNMOUNT;
   1017 
   1018 		mutex_enter(&pmp->pmp_sopmtx);
   1019 		if (pmp->pmp_sopthrcount == 0) {
   1020 			mutex_exit(&pmp->pmp_sopmtx);
   1021 			kmem_free(psopr, sizeof(*psopr));
   1022 			puffs_msg_sendresp(pmp, preq, ENXIO);
   1023 		} else {
   1024 			TAILQ_INSERT_TAIL(&pmp->pmp_sopfastreqs,
   1025 			    psopr, psopr_entries);
   1026 			cv_signal(&pmp->pmp_sopcv);
   1027 			mutex_exit(&pmp->pmp_sopmtx);
   1028 		}
   1029 		break;
   1030 	}
   1031 
   1032 	default:
   1033 		DPRINTF(("dispatch: invalid opclass 0x%x\n", preq->preq_opclass));
   1034 		puffs_msg_sendresp(pmp, preq, EOPNOTSUPP);
   1035 		break;
   1036 	}
   1037 
   1038 	return 0;
   1039 }
   1040 
   1041 /*
   1042  * Work loop for thread processing all ops from server which
   1043  * cannot safely be handled in caller context.  This includes
   1044  * everything which might need a lock currently "held" by the file
   1045  * server, i.e. a long-term kernel lock which will be released only
   1046  * once the file server acknowledges a request
   1047  */
   1048 #define TIMED_OUT(expire) \
   1049     ((int)((unsigned int)getticks() - (unsigned int)expire) > 0)
   1050 void
   1051 puffs_sop_thread(void *arg)
   1052 {
   1053 	struct puffs_mount *pmp = arg;
   1054 	struct mount *mp = PMPTOMP(pmp);
   1055 	struct puffs_sopreq *psopr;
   1056 	bool keeprunning;
   1057 	bool unmountme = false;
   1058 	int timeo;
   1059 
   1060 	timeo = PUFFS_USE_FS_TTL(pmp) ? puffs_sopreq_expire_timeout : 0;
   1061 
   1062 	mutex_enter(&pmp->pmp_sopmtx);
   1063 	for (keeprunning = true; keeprunning; ) {
   1064 		/*
   1065 		 * We have a fast queue for flush and umount, and a node
   1066 		 * queue for delayes node reclaims. Requests on node queue 			 * are not honoured before clock reaches psopr_at. This
   1067 		 * code assumes that requests are ordered by psopr_at.
   1068 		 */
   1069 		do {
   1070 			psopr = TAILQ_FIRST(&pmp->pmp_sopfastreqs);
   1071 			if (psopr != NULL) {
   1072 				TAILQ_REMOVE(&pmp->pmp_sopfastreqs,
   1073 					     psopr, psopr_entries);
   1074 				break;
   1075 			}
   1076 
   1077 			psopr = TAILQ_FIRST(&pmp->pmp_sopnodereqs);
   1078 			if ((psopr != NULL) && TIMED_OUT(psopr->psopr_at)) {
   1079 				TAILQ_REMOVE(&pmp->pmp_sopnodereqs,
   1080 					     psopr, psopr_entries);
   1081 				break;
   1082 			}
   1083 
   1084 			cv_timedwait(&pmp->pmp_sopcv, &pmp->pmp_sopmtx, timeo);
   1085 		} while (1 /* CONSTCOND */);
   1086 
   1087 		mutex_exit(&pmp->pmp_sopmtx);
   1088 
   1089 		switch (psopr->psopr_sopreq) {
   1090 		case PUFFS_SOPREQSYS_EXIT:
   1091 			keeprunning = false;
   1092 			break;
   1093 		case PUFFS_SOPREQ_FLUSH:
   1094 			puffsop_flush(pmp, &psopr->psopr_pf);
   1095 			break;
   1096 		case PUFFS_SOPREQ_EXPIRE:
   1097 			puffsop_expire(pmp, psopr->psopr_ck);
   1098 			break;
   1099 		case PUFFS_SOPREQ_UNMOUNT:
   1100 			puffs_msg_sendresp(pmp, &psopr->psopr_preq, 0);
   1101 
   1102 			unmountme = true;
   1103 			keeprunning = false;
   1104 
   1105 			/*
   1106 			 * We know the mountpoint is still alive because
   1107 			 * the thread that is us (poetic?) is still alive.
   1108 			 */
   1109 			vfs_ref(mp);
   1110 			break;
   1111 		}
   1112 
   1113 		kmem_free(psopr, sizeof(*psopr));
   1114 		mutex_enter(&pmp->pmp_sopmtx);
   1115 	}
   1116 
   1117 	/*
   1118 	 * Purge remaining ops.
   1119 	 */
   1120 	while ((psopr = TAILQ_FIRST(&pmp->pmp_sopfastreqs)) != NULL) {
   1121 		TAILQ_REMOVE(&pmp->pmp_sopfastreqs, psopr, psopr_entries);
   1122 		mutex_exit(&pmp->pmp_sopmtx);
   1123 		puffs_msg_sendresp(pmp, &psopr->psopr_preq, ENXIO);
   1124 		kmem_free(psopr, sizeof(*psopr));
   1125 		mutex_enter(&pmp->pmp_sopmtx);
   1126 	}
   1127 
   1128 	while ((psopr = TAILQ_FIRST(&pmp->pmp_sopnodereqs)) != NULL) {
   1129 		TAILQ_REMOVE(&pmp->pmp_sopnodereqs, psopr, psopr_entries);
   1130 		mutex_exit(&pmp->pmp_sopmtx);
   1131 		KASSERT(psopr->psopr_sopreq == PUFFS_SOPREQ_EXPIRE);
   1132 		kmem_free(psopr, sizeof(*psopr));
   1133 		mutex_enter(&pmp->pmp_sopmtx);
   1134 	}
   1135 
   1136 	pmp->pmp_sopthrcount--;
   1137 	cv_broadcast(&pmp->pmp_sopcv);
   1138 	mutex_exit(&pmp->pmp_sopmtx); /* not allowed to access fs after this */
   1139 
   1140 	/*
   1141 	 * If unmount was requested, we can now safely do it here, since
   1142 	 * our context is dead from the point-of-view of puffs_unmount()
   1143 	 * and we are just another thread.  dounmount() makes internally
   1144 	 * sure that VFS_UNMOUNT() isn't called reentrantly and that it
   1145 	 * is eventually completed.
   1146 	 */
   1147 	if (unmountme) {
   1148 		(void)dounmount(mp, MNT_FORCE, curlwp);
   1149 		vfs_rele(mp);
   1150 	}
   1151 
   1152 	kthread_exit(0);
   1153 }
   1154 
   1155 int
   1156 puffs_msgif_close(void *ctx)
   1157 {
   1158 	struct puffs_mount *pmp = ctx;
   1159 	struct mount *mp = PMPTOMP(pmp);
   1160 
   1161 	mutex_enter(&pmp->pmp_lock);
   1162 	puffs_mp_reference(pmp);
   1163 
   1164 	/*
   1165 	 * Free the waiting callers before proceeding any further.
   1166 	 * The syncer might be jogging around in this file system
   1167 	 * currently.  If we allow it to go to the userspace of no
   1168 	 * return while trying to get the syncer lock, well ...
   1169 	 */
   1170 	puffs_userdead(pmp);
   1171 
   1172 	/*
   1173 	 * Make sure someone from puffs_unmount() isn't currently in
   1174 	 * userspace.  If we don't take this precautionary step,
   1175 	 * they might notice that the mountpoint has disappeared
   1176 	 * from under them once they return.  Especially note that we
   1177 	 * cannot simply test for an unmounter before calling
   1178 	 * dounmount(), since it might be possible that that particular
   1179 	 * invocation of unmount was called without MNT_FORCE.  Here we
   1180 	 * *must* make sure unmount succeeds.  Also, restart is necessary
   1181 	 * since pmp isn't locked.  We might end up with PUTTER_DEAD after
   1182 	 * restart and exit from there.
   1183 	 */
   1184 	if (pmp->pmp_unmounting) {
   1185 		cv_wait(&pmp->pmp_unmounting_cv, &pmp->pmp_lock);
   1186 		puffs_mp_release(pmp);
   1187 		mutex_exit(&pmp->pmp_lock);
   1188 		DPRINTF(("puffs_fop_close: unmount was in progress for pmp %p, "
   1189 		    "restart\n", pmp));
   1190 		return ERESTART;
   1191 	}
   1192 
   1193 	/* Won't access pmp from here anymore */
   1194 	vfs_ref(mp);
   1195 	puffs_mp_release(pmp);
   1196 	mutex_exit(&pmp->pmp_lock);
   1197 
   1198 	/* Detach from VFS. */
   1199 	(void)dounmount(mp, MNT_FORCE, curlwp);
   1200 	vfs_rele(mp);
   1201 
   1202 	return 0;
   1203 }
   1204 
   1205 /*
   1206  * We're dead, kaput, RIP, slightly more than merely pining for the
   1207  * fjords, belly-up, fallen, lifeless, finished, expired, gone to meet
   1208  * our maker, ceased to be, etcetc.  YASD.  It's a dead FS!
   1209  *
   1210  * Caller must hold puffs mutex.
   1211  */
   1212 void
   1213 puffs_userdead(struct puffs_mount *pmp)
   1214 {
   1215 	struct puffs_msgpark *park, *park_next;
   1216 
   1217 	/*
   1218 	 * Mark filesystem status as dying so that operations don't
   1219 	 * attempt to march to userspace any longer.
   1220 	 */
   1221 	pmp->pmp_status = PUFFSTAT_DYING;
   1222 
   1223 	/* signal waiters on REQUEST TO file server queue */
   1224 	for (park = TAILQ_FIRST(&pmp->pmp_msg_touser); park; park = park_next) {
   1225 
   1226 		mutex_enter(&park->park_mtx);
   1227 		puffs_msgpark_reference(park);
   1228 		park_next = TAILQ_NEXT(park, park_entries);
   1229 
   1230 		KASSERT(park->park_flags & PARKFLAG_ONQUEUE1);
   1231 		TAILQ_REMOVE(&pmp->pmp_msg_touser, park, park_entries);
   1232 		park->park_flags &= ~PARKFLAG_ONQUEUE1;
   1233 		pmp->pmp_msg_touser_count--;
   1234 
   1235 		/*
   1236 		 * Even though waiters on QUEUE1 are removed in touser()
   1237 		 * in case of WAITERGONE, it is still possible for us to
   1238 		 * get raced here due to having to retake locks in said
   1239 		 * touser().  In the race case simply "ignore" the item
   1240 		 * on the queue and move on to the next one.
   1241 		 */
   1242 		if (park->park_flags & PARKFLAG_WAITERGONE) {
   1243 			KASSERT((park->park_flags & PARKFLAG_CALL) == 0);
   1244 			KASSERT(park->park_flags & PARKFLAG_WANTREPLY);
   1245 			puffs_msgpark_release(park);
   1246 
   1247 		} else {
   1248 			park->park_preq->preq_rv = ENXIO;
   1249 
   1250 			if (park->park_flags & PARKFLAG_CALL) {
   1251 				park->park_done(pmp, park->park_preq,
   1252 				    park->park_donearg);
   1253 				puffs_msgpark_release1(park, 2);
   1254 			} else if ((park->park_flags & PARKFLAG_WANTREPLY)==0) {
   1255 				puffs_msgpark_release1(park, 2);
   1256 			} else {
   1257 				park->park_preq->preq_rv = ENXIO;
   1258 				cv_signal(&park->park_cv);
   1259 				puffs_msgpark_release(park);
   1260 			}
   1261 		}
   1262 	}
   1263 
   1264 	/* signal waiters on RESPONSE FROM file server queue */
   1265 	for (park=TAILQ_FIRST(&pmp->pmp_msg_replywait); park; park=park_next) {
   1266 		mutex_enter(&park->park_mtx);
   1267 		puffs_msgpark_reference(park);
   1268 		park_next = TAILQ_NEXT(park, park_entries);
   1269 
   1270 		KASSERT(park->park_flags & PARKFLAG_ONQUEUE2);
   1271 		KASSERT(park->park_flags & PARKFLAG_WANTREPLY);
   1272 
   1273 		TAILQ_REMOVE(&pmp->pmp_msg_replywait, park, park_entries);
   1274 		park->park_flags &= ~PARKFLAG_ONQUEUE2;
   1275 
   1276 		if (park->park_flags & PARKFLAG_WAITERGONE) {
   1277 			KASSERT((park->park_flags & PARKFLAG_CALL) == 0);
   1278 			puffs_msgpark_release(park);
   1279 		} else {
   1280 			park->park_preq->preq_rv = ENXIO;
   1281 			if (park->park_flags & PARKFLAG_CALL) {
   1282 				park->park_done(pmp, park->park_preq,
   1283 				    park->park_donearg);
   1284 				puffs_msgpark_release1(park, 2);
   1285 			} else {
   1286 				cv_signal(&park->park_cv);
   1287 				puffs_msgpark_release(park);
   1288 			}
   1289 		}
   1290 	}
   1291 
   1292 	cv_broadcast(&pmp->pmp_msg_waiter_cv);
   1293 }
   1294