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puffs.c revision 1.70 
      1 /*	$NetBSD: puffs.c,v 1.70 2007/10/26 17:35:01 pooka 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 #if !defined(lint)
     34 __RCSID("$NetBSD: puffs.c,v 1.70 2007/10/26 17:35:01 pooka Exp $");
     35 #endif /* !lint */
     36 
     37 #include <sys/param.h>
     38 #include <sys/mount.h>
     39 
     40 #include <assert.h>
     41 #include <err.h>
     42 #include <errno.h>
     43 #include <fcntl.h>
     44 #include <mntopts.h>
     45 #include <paths.h>
     46 #include <puffs.h>
     47 #include <stdio.h>
     48 #include <stdlib.h>
     49 #include <string.h>
     50 #include <syslog.h>
     51 #include <unistd.h>
     52 
     53 #include "puffs_priv.h"
     54 
     55 /* Most file systems want this for opts, so just give it to them */
     56 const struct mntopt puffsmopts[] = {
     57 	MOPT_STDOPTS,
     58 	PUFFSMOPT_STD,
     59 	MOPT_NULL,
     60 };
     61 
     62 #define FILLOP(lower, upper)						\
     63 do {									\
     64 	if (pops->puffs_node_##lower)					\
     65 		opmask[PUFFS_VN_##upper] = 1;				\
     66 } while (/*CONSTCOND*/0)
     67 static void
     68 fillvnopmask(struct puffs_ops *pops, uint8_t *opmask)
     69 {
     70 
     71 	memset(opmask, 0, PUFFS_VN_MAX);
     72 
     73 	FILLOP(create,   CREATE);
     74 	FILLOP(mknod,    MKNOD);
     75 	FILLOP(open,     OPEN);
     76 	FILLOP(close,    CLOSE);
     77 	FILLOP(access,   ACCESS);
     78 	FILLOP(getattr,  GETATTR);
     79 	FILLOP(setattr,  SETATTR);
     80 	FILLOP(poll,     POLL); /* XXX: not ready in kernel */
     81 	FILLOP(mmap,     MMAP);
     82 	FILLOP(fsync,    FSYNC);
     83 	FILLOP(seek,     SEEK);
     84 	FILLOP(remove,   REMOVE);
     85 	FILLOP(link,     LINK);
     86 	FILLOP(rename,   RENAME);
     87 	FILLOP(mkdir,    MKDIR);
     88 	FILLOP(rmdir,    RMDIR);
     89 	FILLOP(symlink,  SYMLINK);
     90 	FILLOP(readdir,  READDIR);
     91 	FILLOP(readlink, READLINK);
     92 	FILLOP(reclaim,  RECLAIM);
     93 	FILLOP(inactive, INACTIVE);
     94 	FILLOP(print,    PRINT);
     95 	FILLOP(read,     READ);
     96 	FILLOP(write,    WRITE);
     97 }
     98 #undef FILLOP
     99 
    100 /*ARGSUSED*/
    101 static void
    102 puffs_defaulterror(struct puffs_usermount *pu, uint8_t type,
    103 	int error, const char *str, void *cookie)
    104 {
    105 
    106 	fprintf(stderr, "%s\n", str);
    107 	abort();
    108 }
    109 
    110 int
    111 puffs_getselectable(struct puffs_usermount *pu)
    112 {
    113 
    114 	return pu->pu_fd;
    115 }
    116 
    117 int
    118 puffs_setblockingmode(struct puffs_usermount *pu, int mode)
    119 {
    120 	int rv, x;
    121 
    122 	if (mode != PUFFSDEV_BLOCK && mode != PUFFSDEV_NONBLOCK) {
    123 		errno = EINVAL;
    124 		return -1;
    125 	}
    126 
    127 	x = mode;
    128 	rv = ioctl(pu->pu_fd, FIONBIO, &x);
    129 
    130 	if (rv == 0) {
    131 		if (mode == PUFFSDEV_BLOCK)
    132 			pu->pu_state &= ~PU_ASYNCFD;
    133 		else
    134 			pu->pu_state |= PU_ASYNCFD;
    135 	}
    136 
    137 	return rv;
    138 }
    139 
    140 int
    141 puffs_getstate(struct puffs_usermount *pu)
    142 {
    143 
    144 	return pu->pu_state & PU_STATEMASK;
    145 }
    146 
    147 void
    148 puffs_setstacksize(struct puffs_usermount *pu, size_t ss)
    149 {
    150 	int stackshift;
    151 
    152 	assert(puffs_getstate(pu) == PUFFS_STATE_BEFOREMOUNT);
    153 	stackshift = -1;
    154 	while (ss) {
    155 		ss >>= 1;
    156 		stackshift++;
    157 	}
    158 	pu->pu_cc_stackshift = stackshift;
    159 	assert(1<<stackshift == ss);
    160 }
    161 
    162 struct puffs_pathobj *
    163 puffs_getrootpathobj(struct puffs_usermount *pu)
    164 {
    165 	struct puffs_node *pnr;
    166 
    167 	pnr = pu->pu_pn_root;
    168 	if (pnr == NULL) {
    169 		errno = ENOENT;
    170 		return NULL;
    171 	}
    172 
    173 	return &pnr->pn_po;
    174 }
    175 
    176 void
    177 puffs_setroot(struct puffs_usermount *pu, struct puffs_node *pn)
    178 {
    179 
    180 	pu->pu_pn_root = pn;
    181 }
    182 
    183 struct puffs_node *
    184 puffs_getroot(struct puffs_usermount *pu)
    185 {
    186 
    187 	return pu->pu_pn_root;
    188 }
    189 
    190 void
    191 puffs_setrootinfo(struct puffs_usermount *pu, enum vtype vt,
    192 	vsize_t vsize, dev_t rdev)
    193 {
    194 	struct puffs_kargs *pargs = pu->pu_kargp;
    195 
    196 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT) {
    197 		warnx("puffs_setrootinfo: call has effect only "
    198 		    "before mount\n");
    199 		return;
    200 	}
    201 
    202 	pargs->pa_root_vtype = vt;
    203 	pargs->pa_root_vsize = vsize;
    204 	pargs->pa_root_rdev = rdev;
    205 }
    206 
    207 void *
    208 puffs_getspecific(struct puffs_usermount *pu)
    209 {
    210 
    211 	return pu->pu_privdata;
    212 }
    213 
    214 size_t
    215 puffs_getmaxreqlen(struct puffs_usermount *pu)
    216 {
    217 
    218 	return pu->pu_maxreqlen;
    219 }
    220 
    221 void
    222 puffs_setmaxreqlen(struct puffs_usermount *pu, size_t reqlen)
    223 {
    224 
    225 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT)
    226 		warnx("puffs_setmaxreqlen: call has effect only "
    227 		    "before mount\n");
    228 
    229 	pu->pu_kargp->pa_maxmsglen = reqlen;
    230 }
    231 
    232 void
    233 puffs_setfhsize(struct puffs_usermount *pu, size_t fhsize, int flags)
    234 {
    235 
    236 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT)
    237 		warnx("puffs_setfhsize: call has effect only before mount\n");
    238 
    239 	pu->pu_kargp->pa_fhsize = fhsize;
    240 	pu->pu_kargp->pa_fhflags = flags;
    241 }
    242 
    243 void
    244 puffs_setncookiehash(struct puffs_usermount *pu, int nhash)
    245 {
    246 
    247 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT)
    248 		warnx("puffs_setfhsize: call has effect only before mount\n");
    249 
    250 	pu->pu_kargp->pa_nhashbuckets = nhash;
    251 }
    252 
    253 void
    254 puffs_set_pathbuild(struct puffs_usermount *pu, pu_pathbuild_fn fn)
    255 {
    256 
    257 	pu->pu_pathbuild = fn;
    258 }
    259 
    260 void
    261 puffs_set_pathtransform(struct puffs_usermount *pu, pu_pathtransform_fn fn)
    262 {
    263 
    264 	pu->pu_pathtransform = fn;
    265 }
    266 
    267 void
    268 puffs_set_pathcmp(struct puffs_usermount *pu, pu_pathcmp_fn fn)
    269 {
    270 
    271 	pu->pu_pathcmp = fn;
    272 }
    273 
    274 void
    275 puffs_set_pathfree(struct puffs_usermount *pu, pu_pathfree_fn fn)
    276 {
    277 
    278 	pu->pu_pathfree = fn;
    279 }
    280 
    281 void
    282 puffs_set_namemod(struct puffs_usermount *pu, pu_namemod_fn fn)
    283 {
    284 
    285 	pu->pu_namemod = fn;
    286 }
    287 
    288 void
    289 puffs_set_errnotify(struct puffs_usermount *pu, pu_errnotify_fn fn)
    290 {
    291 
    292 	pu->pu_errnotify = fn;
    293 }
    294 
    295 void
    296 puffs_ml_setloopfn(struct puffs_usermount *pu, puffs_ml_loop_fn lfn)
    297 {
    298 
    299 	pu->pu_ml_lfn = lfn;
    300 }
    301 
    302 void
    303 puffs_ml_settimeout(struct puffs_usermount *pu, struct timespec *ts)
    304 {
    305 
    306 	if (ts == NULL) {
    307 		pu->pu_ml_timep = NULL;
    308 	} else {
    309 		pu->pu_ml_timeout = *ts;
    310 		pu->pu_ml_timep = &pu->pu_ml_timeout;
    311 	}
    312 }
    313 
    314 void
    315 puffs_setback(struct puffs_cc *pcc, int whatback)
    316 {
    317 	struct puffs_req *preq = pcc->pcc_preq;
    318 
    319 	assert(PUFFSOP_OPCLASS(preq->preq_opclass) == PUFFSOP_VN && (
    320 	    preq->preq_optype == PUFFS_VN_OPEN ||
    321 	    preq->preq_optype == PUFFS_VN_MMAP ||
    322 	    preq->preq_optype == PUFFS_VN_REMOVE ||
    323 	    preq->preq_optype == PUFFS_VN_RMDIR ||
    324 	    preq->preq_optype == PUFFS_VN_INACTIVE));
    325 
    326 	preq->preq_setbacks |= whatback & PUFFS_SETBACK_MASK;
    327 }
    328 
    329 int
    330 puffs_mount(struct puffs_usermount *pu, const char *dir, int mntflags,
    331 	void *cookie)
    332 {
    333 	char rp[MAXPATHLEN];
    334 	int rv;
    335 
    336 #if 1
    337 	/* XXXkludgehere */
    338 	/* kauth doesn't provide this service any longer */
    339 	if (geteuid() != 0)
    340 		mntflags |= MNT_NOSUID | MNT_NODEV;
    341 #endif
    342 
    343 	if (realpath(dir, rp) == NULL)
    344 		return -1;
    345 
    346 	if (strcmp(dir, rp) != 0) {
    347 		warnx("puffs_mount: \"%s\" is a relative path.", dir);
    348 		warnx("puffs_mount: using \"%s\" instead.", rp);
    349 	}
    350 
    351 	pu->pu_kargp->pa_root_cookie = cookie;
    352 	if ((rv = mount(MOUNT_PUFFS, rp, mntflags,
    353 	    pu->pu_kargp, sizeof(struct puffs_kargs))) == -1)
    354 		goto out;
    355 #if 0
    356 	if ((rv = ioctl(pu->pu_fd, PUFFSREQSIZEOP, &pu->pu_maxreqlen)) == -1)
    357 		goto out;
    358 #endif
    359 	PU_SETSTATE(pu, PUFFS_STATE_RUNNING);
    360 
    361  out:
    362 	free(pu->pu_kargp);
    363 	pu->pu_kargp = NULL;
    364 
    365 	return rv;
    366 }
    367 
    368 struct puffs_usermount *
    369 _puffs_init(int develv, struct puffs_ops *pops, const char *mntfromname,
    370 	const char *puffsname, void *priv, uint32_t pflags)
    371 {
    372 	struct puffs_usermount *pu;
    373 	struct puffs_kargs *pargs;
    374 	int sverrno, fd;
    375 
    376 	if (develv != PUFFS_DEVEL_LIBVERSION) {
    377 		warnx("puffs_init: mounting with lib version %d, need %d",
    378 		    develv, PUFFS_DEVEL_LIBVERSION);
    379 		errno = EINVAL;
    380 		return NULL;
    381 	}
    382 
    383 	fd = open(_PATH_PUFFS, O_RDONLY);
    384 	if (fd == -1) {
    385 		warnx("puffs_init: cannot open %s", _PATH_PUFFS);
    386 		return NULL;
    387 	}
    388 	if (fd <= 2)
    389 		warnx("puffs_init: device fd %d (<= 2), sure this is "
    390 		    "what you want?", fd);
    391 
    392 	pu = malloc(sizeof(struct puffs_usermount));
    393 	if (pu == NULL)
    394 		goto failfree;
    395 	memset(pu, 0, sizeof(struct puffs_usermount));
    396 
    397 	pargs = pu->pu_kargp = malloc(sizeof(struct puffs_kargs));
    398 	if (pargs == NULL)
    399 		goto failfree;
    400 	memset(pargs, 0, sizeof(struct puffs_kargs));
    401 
    402 	pargs->pa_vers = PUFFSDEVELVERS | PUFFSVERSION;
    403 	pargs->pa_flags = PUFFS_FLAG_KERN(pflags);
    404 	pargs->pa_fd = pu->pu_fd = fd;
    405 	fillvnopmask(pops, pargs->pa_vnopmask);
    406 	(void)strlcpy(pargs->pa_typename, puffsname,
    407 	    sizeof(pargs->pa_typename));
    408 	(void)strlcpy(pargs->pa_mntfromname, mntfromname,
    409 	    sizeof(pargs->pa_mntfromname));
    410 
    411 	puffs_zerostatvfs(&pargs->pa_svfsb);
    412 	pargs->pa_root_cookie = NULL;
    413 	pargs->pa_root_vtype = VDIR;
    414 	pargs->pa_root_vsize = 0;
    415 	pargs->pa_root_rdev = 0;
    416 	pargs->pa_maxmsglen = 0;
    417 
    418 	pu->pu_flags = pflags;
    419 	pu->pu_ops = *pops;
    420 	free(pops); /* XXX */
    421 
    422 	pu->pu_privdata = priv;
    423 	pu->pu_cc_stackshift = PUFFS_CC_STACKSHIFT_DEFAULT;
    424 	LIST_INIT(&pu->pu_pnodelst);
    425 	LIST_INIT(&pu->pu_framectrl.fb_ios);
    426 	LIST_INIT(&pu->pu_ccnukelst);
    427 	TAILQ_INIT(&pu->pu_sched);
    428 	TAILQ_INIT(&pu->pu_exq);
    429 
    430 	/* defaults for some user-settable translation functions */
    431 	pu->pu_cmap = NULL; /* identity translation */
    432 
    433 	pu->pu_pathbuild = puffs_stdpath_buildpath;
    434 	pu->pu_pathfree = puffs_stdpath_freepath;
    435 	pu->pu_pathcmp = puffs_stdpath_cmppath;
    436 	pu->pu_pathtransform = NULL;
    437 	pu->pu_namemod = NULL;
    438 
    439 	pu->pu_errnotify = puffs_defaulterror;
    440 
    441 	PU_SETSTATE(pu, PUFFS_STATE_BEFOREMOUNT);
    442 
    443 	return pu;
    444 
    445  failfree:
    446 	/* can't unmount() from here for obvious reasons */
    447 	sverrno = errno;
    448 	close(fd);
    449 	free(pu);
    450 	errno = sverrno;
    451 	return NULL;
    452 }
    453 
    454 /*
    455  * XXX: there's currently no clean way to request unmount from
    456  * within the user server, so be very brutal about it.
    457  */
    458 /*ARGSUSED1*/
    459 int
    460 puffs_exit(struct puffs_usermount *pu, int force)
    461 {
    462 	struct puffs_node *pn;
    463 
    464 	force = 1; /* currently */
    465 
    466 	if (pu->pu_fd)
    467 		close(pu->pu_fd);
    468 
    469 	while ((pn = LIST_FIRST(&pu->pu_pnodelst)) != NULL)
    470 		puffs_pn_put(pn);
    471 
    472 	puffs_framev_exit(pu);
    473 	if (pu->pu_state & PU_HASKQ)
    474 		close(pu->pu_kq);
    475 	free(pu);
    476 
    477 	return 0; /* always succesful for now, WILL CHANGE */
    478 }
    479 
    480 int
    481 puffs_mainloop(struct puffs_usermount *pu, int flags)
    482 {
    483 	struct puffs_getreq *pgr = NULL;
    484 	struct puffs_putreq *ppr = NULL;
    485 	struct puffs_framectrl *pfctrl = &pu->pu_framectrl;
    486 	struct puffs_fctrl_io *fio;
    487 	struct puffs_cc *pcc;
    488 	struct kevent *curev, *newevs;
    489 	size_t nchanges;
    490 	int puffsfd, sverrno;
    491 	int ndone;
    492 
    493 	assert(puffs_getstate(pu) >= PUFFS_STATE_RUNNING);
    494 
    495 	pgr = puffs_req_makeget(pu, puffs_getmaxreqlen(pu), 0);
    496 	if (pgr == NULL)
    497 		goto out;
    498 
    499 	ppr = puffs_req_makeput(pu);
    500 	if (ppr == NULL)
    501 		goto out;
    502 
    503 	newevs = realloc(pfctrl->evs, (2*pfctrl->nfds+1)*sizeof(struct kevent));
    504 	if (newevs == NULL)
    505 		goto out;
    506 	pfctrl->evs = newevs;
    507 
    508 	if ((flags & PUFFSLOOP_NODAEMON) == 0)
    509 		if (daemon(1, 0) == -1)
    510 			goto out;
    511 	pu->pu_state |= PU_INLOOP;
    512 
    513 	pu->pu_kq = kqueue();
    514 	if (pu->pu_kq == -1)
    515 		goto out;
    516 	pu->pu_state |= PU_HASKQ;
    517 
    518 	curev = pfctrl->evs;
    519 	LIST_FOREACH(fio, &pfctrl->fb_ios, fio_entries) {
    520 		EV_SET(curev, fio->io_fd, EVFILT_READ, EV_ADD,
    521 		    0, 0, (uintptr_t)fio);
    522 		curev++;
    523 		EV_SET(curev, fio->io_fd, EVFILT_WRITE, EV_ADD | EV_DISABLE,
    524 		    0, 0, (uintptr_t)fio);
    525 		curev++;
    526 	}
    527 	puffsfd = puffs_getselectable(pu);
    528 	EV_SET(curev, puffsfd, EVFILT_READ, EV_ADD, 0, 0, 0);
    529 	if (kevent(pu->pu_kq, pfctrl->evs, 2*pfctrl->nfds+1,
    530 	    NULL, 0, NULL) == -1)
    531 		goto out;
    532 
    533 	while (puffs_getstate(pu) != PUFFS_STATE_UNMOUNTED) {
    534 		if (pu->pu_ml_lfn)
    535 			pu->pu_ml_lfn(pu);
    536 
    537 		/*
    538 		 * Do this here, because:
    539 		 *  a) loopfunc might generate some results
    540 		 *  b) it's still "after" event handling (except for round 1)
    541 		 */
    542 		if (puffs_req_putput(ppr) == -1)
    543 			goto out;
    544 		puffs_req_resetput(ppr);
    545 
    546 		/* micro optimization: skip kevent syscall if possible */
    547 		if (pfctrl->nfds == 0 && pu->pu_ml_timep == NULL
    548 		    && (pu->pu_state & PU_ASYNCFD) == 0) {
    549 			if (puffs_req_handle(pgr, ppr, 0) == -1)
    550 				goto out;
    551 			continue;
    552 		}
    553 
    554 		/* else: do full processing */
    555 
    556 		/*
    557 		 * Build list of which to enable/disable in writecheck.
    558 		 * Don't bother worrying about O(n) for now.
    559 		 */
    560 		nchanges = 0;
    561 		LIST_FOREACH(fio, &pfctrl->fb_ios, fio_entries) {
    562 			if (fio->stat & FIO_WRGONE)
    563 				continue;
    564 
    565 			/*
    566 			 * Try to write out everything to avoid the
    567 			 * need for enabling EVFILT_WRITE.  The likely
    568 			 * case is that we can fit everything into the
    569 			 * socket buffer.
    570 			 */
    571 			if (puffs_framev_output(pu, pfctrl, fio, ppr)) {
    572 				/* need kernel notify? (error condition) */
    573 				if (puffs_req_putput(ppr) == -1)
    574 					goto out;
    575 				puffs_req_resetput(ppr);
    576 			}
    577 
    578 			/* en/disable write checks for kqueue as needed */
    579 			assert((FIO_EN_WRITE(fio) && FIO_RM_WRITE(fio)) == 0);
    580 			if (FIO_EN_WRITE(fio)) {
    581 				EV_SET(&pfctrl->evs[nchanges], fio->io_fd,
    582 				    EVFILT_WRITE, EV_ENABLE, 0, 0,
    583 				    (uintptr_t)fio);
    584 				fio->stat |= FIO_WR;
    585 				nchanges++;
    586 			}
    587 			if (FIO_RM_WRITE(fio)) {
    588 				EV_SET(&pfctrl->evs[nchanges], fio->io_fd,
    589 				    EVFILT_WRITE, EV_DISABLE, 0, 0,
    590 				    (uintptr_t)fio);
    591 				fio->stat &= ~FIO_WR;
    592 				nchanges++;
    593 			}
    594 			assert(nchanges <= pfctrl->nfds);
    595 		}
    596 
    597 		ndone = kevent(pu->pu_kq, pfctrl->evs, nchanges,
    598 		    pfctrl->evs, pfctrl->nfds+1, pu->pu_ml_timep);
    599 
    600 		if (ndone == -1) {
    601 			if (errno != EINTR)
    602 				goto out;
    603 			else
    604 				continue;
    605 		}
    606 
    607 		/* uoptimize */
    608 		if (ndone == 0)
    609 			continue;
    610 
    611 		/* iterate over the results */
    612 		for (curev = pfctrl->evs; ndone--; curev++) {
    613 			int what;
    614 
    615 			/* get & possibly dispatch events from kernel */
    616 			if (curev->ident == puffsfd) {
    617 				if (puffs_req_handle(pgr, ppr, 0) == -1)
    618 					goto out;
    619 				continue;
    620 			}
    621 
    622 			fio = (void *)curev->udata;
    623 			if (curev->flags & EV_ERROR) {
    624 				assert(curev->filter == EVFILT_WRITE);
    625 				fio->stat &= ~FIO_WR;
    626 
    627 				/* XXX: how to know if it's a transient error */
    628 				puffs_framev_writeclose(pu, fio,
    629 				    (int)curev->data);
    630 				puffs_framev_notify(fio, PUFFS_FBIO_ERROR);
    631 				continue;
    632 			}
    633 
    634 			what = 0;
    635 			if (curev->filter == EVFILT_READ) {
    636 				puffs_framev_input(pu, pfctrl, fio, ppr);
    637 				what |= PUFFS_FBIO_READ;
    638 			}
    639 
    640 			else if (curev->filter == EVFILT_WRITE) {
    641 				puffs_framev_output(pu, pfctrl, fio, ppr);
    642 				what |= PUFFS_FBIO_WRITE;
    643 			}
    644 			if (what)
    645 				puffs_framev_notify(fio, what);
    646 		}
    647 
    648 		/*
    649 		 * Schedule continuations.
    650 		 */
    651 		while ((pcc = TAILQ_FIRST(&pu->pu_sched)) != NULL) {
    652 			TAILQ_REMOVE(&pu->pu_sched, pcc, entries);
    653 			puffs_goto(pcc);
    654 		}
    655 
    656 		/*
    657 		 * Really free fd's now that we don't have references
    658 		 * to them.
    659 		 */
    660 		while ((fio = LIST_FIRST(&pfctrl->fb_ios_rmlist)) != NULL) {
    661 			LIST_REMOVE(fio, fio_entries);
    662 			free(fio);
    663 		}
    664 	}
    665 	errno = 0;
    666 	puffs_req_putput(ppr);
    667 
    668  out:
    669 	/* store the real error for a while */
    670 	sverrno = errno;
    671 
    672 	if (ppr)
    673 		puffs_req_destroyput(ppr);
    674 	if (pgr)
    675 		puffs_req_destroyget(pgr);
    676 
    677 	errno = sverrno;
    678 	if (errno)
    679 		return -1;
    680 	else
    681 		return 0;
    682 }
    683