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puffs.c revision 1.114
      1 /*	$NetBSD: puffs.c,v 1.114 2010/07/06 21:58:18 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 1.114 2010/07/06 21:58:18 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 #ifdef PUFFS_WITH_THREADS
     63 #include <pthread.h>
     64 pthread_mutex_t pu_lock = PTHREAD_MUTEX_INITIALIZER;
     65 #endif
     66 
     67 #define FILLOP(lower, upper)						\
     68 do {									\
     69 	if (pops->puffs_node_##lower)					\
     70 		opmask[PUFFS_VN_##upper] = 1;				\
     71 } while (/*CONSTCOND*/0)
     72 static void
     73 fillvnopmask(struct puffs_ops *pops, struct puffs_kargs *pa)
     74 {
     75 	uint8_t *opmask = pa->pa_vnopmask;
     76 
     77 	memset(opmask, 0, sizeof(pa->pa_vnopmask));
     78 
     79 	FILLOP(create,   CREATE);
     80 	FILLOP(mknod,    MKNOD);
     81 	FILLOP(open,     OPEN);
     82 	FILLOP(close,    CLOSE);
     83 	FILLOP(access,   ACCESS);
     84 	FILLOP(getattr,  GETATTR);
     85 	FILLOP(setattr,  SETATTR);
     86 	FILLOP(poll,     POLL);
     87 	FILLOP(mmap,     MMAP);
     88 	FILLOP(fsync,    FSYNC);
     89 	FILLOP(seek,     SEEK);
     90 	FILLOP(remove,   REMOVE);
     91 	FILLOP(link,     LINK);
     92 	FILLOP(rename,   RENAME);
     93 	FILLOP(mkdir,    MKDIR);
     94 	FILLOP(rmdir,    RMDIR);
     95 	FILLOP(symlink,  SYMLINK);
     96 	FILLOP(readdir,  READDIR);
     97 	FILLOP(readlink, READLINK);
     98 	FILLOP(reclaim,  RECLAIM);
     99 	FILLOP(inactive, INACTIVE);
    100 	FILLOP(print,    PRINT);
    101 	FILLOP(read,     READ);
    102 	FILLOP(write,    WRITE);
    103 	FILLOP(abortop,  ABORTOP);
    104 	FILLOP(pathconf, PATHCONF);
    105 
    106 	FILLOP(getextattr,  GETEXTATTR);
    107 	FILLOP(setextattr,  SETEXTATTR);
    108 	FILLOP(listextattr, LISTEXTATTR);
    109 	FILLOP(deleteextattr, DELETEEXTATTR);
    110 }
    111 #undef FILLOP
    112 
    113 /*
    114  * Go over all framev entries and write everything we can.  This is
    115  * mostly for the benefit of delivering "unmount" to the kernel.
    116  */
    117 static void
    118 finalpush(struct puffs_usermount *pu)
    119 {
    120 	struct puffs_fctrl_io *fio;
    121 
    122 	LIST_FOREACH(fio, &pu->pu_ios, fio_entries) {
    123 		if (fio->stat & FIO_WRGONE)
    124 			continue;
    125 
    126 		puffs__framev_output(pu, fio->fctrl, fio);
    127 	}
    128 }
    129 
    130 /*ARGSUSED*/
    131 void
    132 puffs_kernerr_abort(struct puffs_usermount *pu, uint8_t type,
    133 	int error, const char *str, puffs_cookie_t cookie)
    134 {
    135 
    136 	fprintf(stderr, "abort: type %d, error %d, cookie %p (%s)\n",
    137 	    type, error, cookie, str);
    138 	abort();
    139 }
    140 
    141 /*ARGSUSED*/
    142 void
    143 puffs_kernerr_log(struct puffs_usermount *pu, uint8_t type,
    144 	int error, const char *str, puffs_cookie_t cookie)
    145 {
    146 
    147 	syslog(LOG_WARNING, "kernel: type %d, error %d, cookie %p (%s)\n",
    148 	    type, error, cookie, str);
    149 }
    150 
    151 int
    152 puffs_getselectable(struct puffs_usermount *pu)
    153 {
    154 
    155 	return pu->pu_fd;
    156 }
    157 
    158 uint64_t
    159 puffs__nextreq(struct puffs_usermount *pu)
    160 {
    161 	uint64_t rv;
    162 
    163 	PU_LOCK();
    164 	rv = pu->pu_nextreq++ | (uint64_t)1<<63;
    165 	PU_UNLOCK();
    166 
    167 	return rv;
    168 }
    169 
    170 int
    171 puffs_setblockingmode(struct puffs_usermount *pu, int mode)
    172 {
    173 	int rv, x;
    174 
    175 	assert(puffs_getstate(pu) == PUFFS_STATE_RUNNING);
    176 
    177 	if (mode != PUFFSDEV_BLOCK && mode != PUFFSDEV_NONBLOCK) {
    178 		errno = EINVAL;
    179 		return -1;
    180 	}
    181 
    182 	x = mode;
    183 	rv = ioctl(pu->pu_fd, FIONBIO, &x);
    184 
    185 	if (rv == 0) {
    186 		if (mode == PUFFSDEV_BLOCK)
    187 			pu->pu_state &= ~PU_ASYNCFD;
    188 		else
    189 			pu->pu_state |= PU_ASYNCFD;
    190 	}
    191 
    192 	return rv;
    193 }
    194 
    195 int
    196 puffs_getstate(struct puffs_usermount *pu)
    197 {
    198 
    199 	return pu->pu_state & PU_STATEMASK;
    200 }
    201 
    202 void
    203 puffs_setstacksize(struct puffs_usermount *pu, size_t ss)
    204 {
    205 	long psize, minsize;
    206 	int stackshift;
    207 	int bonus;
    208 
    209 	assert(puffs_getstate(pu) == PUFFS_STATE_BEFOREMOUNT);
    210 
    211 	psize = sysconf(_SC_PAGESIZE);
    212 	minsize = 4*psize;
    213 	if (ss < (size_t)minsize || ss == PUFFS_STACKSIZE_MIN) {
    214 		if (ss != PUFFS_STACKSIZE_MIN)
    215 			fprintf(stderr, "puffs_setstacksize: adjusting "
    216 			    "stacksize to minimum %ld\n", minsize);
    217 		ss = 4*psize;
    218 	}
    219 
    220 	stackshift = -1;
    221 	bonus = 0;
    222 	while (ss) {
    223 		if (ss & 0x1)
    224 			bonus++;
    225 		ss >>= 1;
    226 		stackshift++;
    227 	}
    228 	if (bonus > 1) {
    229 		stackshift++;
    230 		fprintf(stderr, "puffs_setstacksize: using next power of two: "
    231 		    "%d\n", 1<<stackshift);
    232 	}
    233 
    234 	pu->pu_cc_stackshift = stackshift;
    235 }
    236 
    237 struct puffs_pathobj *
    238 puffs_getrootpathobj(struct puffs_usermount *pu)
    239 {
    240 	struct puffs_node *pnr;
    241 
    242 	pnr = pu->pu_pn_root;
    243 	if (pnr == NULL) {
    244 		errno = ENOENT;
    245 		return NULL;
    246 	}
    247 
    248 	return &pnr->pn_po;
    249 }
    250 
    251 void
    252 puffs_setroot(struct puffs_usermount *pu, struct puffs_node *pn)
    253 {
    254 
    255 	pu->pu_pn_root = pn;
    256 }
    257 
    258 struct puffs_node *
    259 puffs_getroot(struct puffs_usermount *pu)
    260 {
    261 
    262 	return pu->pu_pn_root;
    263 }
    264 
    265 void
    266 puffs_setrootinfo(struct puffs_usermount *pu, enum vtype vt,
    267 	vsize_t vsize, dev_t rdev)
    268 {
    269 	struct puffs_kargs *pargs = pu->pu_kargp;
    270 
    271 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT) {
    272 		warnx("puffs_setrootinfo: call has effect only "
    273 		    "before mount\n");
    274 		return;
    275 	}
    276 
    277 	pargs->pa_root_vtype = vt;
    278 	pargs->pa_root_vsize = vsize;
    279 	pargs->pa_root_rdev = rdev;
    280 }
    281 
    282 void *
    283 puffs_getspecific(struct puffs_usermount *pu)
    284 {
    285 
    286 	return pu->pu_privdata;
    287 }
    288 
    289 void
    290 puffs_setspecific(struct puffs_usermount *pu, void *privdata)
    291 {
    292 
    293 	pu->pu_privdata = privdata;
    294 }
    295 
    296 void
    297 puffs_setmntinfo(struct puffs_usermount *pu,
    298 	const char *mntfromname, const char *puffsname)
    299 {
    300 	struct puffs_kargs *pargs = pu->pu_kargp;
    301 
    302 	(void)strlcpy(pargs->pa_mntfromname, mntfromname,
    303 	    sizeof(pargs->pa_mntfromname));
    304 	(void)strlcpy(pargs->pa_typename, puffsname,
    305 	    sizeof(pargs->pa_typename));
    306 }
    307 
    308 size_t
    309 puffs_getmaxreqlen(struct puffs_usermount *pu)
    310 {
    311 
    312 	return pu->pu_maxreqlen;
    313 }
    314 
    315 void
    316 puffs_setmaxreqlen(struct puffs_usermount *pu, size_t reqlen)
    317 {
    318 
    319 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT)
    320 		warnx("puffs_setmaxreqlen: call has effect only "
    321 		    "before mount\n");
    322 
    323 	pu->pu_kargp->pa_maxmsglen = reqlen;
    324 }
    325 
    326 void
    327 puffs_setfhsize(struct puffs_usermount *pu, size_t fhsize, int flags)
    328 {
    329 
    330 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT)
    331 		warnx("puffs_setfhsize: call has effect only before mount\n");
    332 
    333 	pu->pu_kargp->pa_fhsize = fhsize;
    334 	pu->pu_kargp->pa_fhflags = flags;
    335 }
    336 
    337 void
    338 puffs_setncookiehash(struct puffs_usermount *pu, int nhash)
    339 {
    340 
    341 	if (puffs_getstate(pu) != PUFFS_STATE_BEFOREMOUNT)
    342 		warnx("puffs_setfhsize: call has effect only before mount\n");
    343 
    344 	pu->pu_kargp->pa_nhashbuckets = nhash;
    345 }
    346 
    347 void
    348 puffs_set_pathbuild(struct puffs_usermount *pu, pu_pathbuild_fn fn)
    349 {
    350 
    351 	pu->pu_pathbuild = fn;
    352 }
    353 
    354 void
    355 puffs_set_pathtransform(struct puffs_usermount *pu, pu_pathtransform_fn fn)
    356 {
    357 
    358 	pu->pu_pathtransform = fn;
    359 }
    360 
    361 void
    362 puffs_set_pathcmp(struct puffs_usermount *pu, pu_pathcmp_fn fn)
    363 {
    364 
    365 	pu->pu_pathcmp = fn;
    366 }
    367 
    368 void
    369 puffs_set_pathfree(struct puffs_usermount *pu, pu_pathfree_fn fn)
    370 {
    371 
    372 	pu->pu_pathfree = fn;
    373 }
    374 
    375 void
    376 puffs_set_namemod(struct puffs_usermount *pu, pu_namemod_fn fn)
    377 {
    378 
    379 	pu->pu_namemod = fn;
    380 }
    381 
    382 void
    383 puffs_set_errnotify(struct puffs_usermount *pu, pu_errnotify_fn fn)
    384 {
    385 
    386 	pu->pu_errnotify = fn;
    387 }
    388 
    389 void
    390 puffs_set_cmap(struct puffs_usermount *pu, pu_cmap_fn fn)
    391 {
    392 
    393 	pu->pu_cmap = fn;
    394 }
    395 
    396 void
    397 puffs_ml_setloopfn(struct puffs_usermount *pu, puffs_ml_loop_fn lfn)
    398 {
    399 
    400 	pu->pu_ml_lfn = lfn;
    401 }
    402 
    403 void
    404 puffs_ml_settimeout(struct puffs_usermount *pu, struct timespec *ts)
    405 {
    406 
    407 	if (ts == NULL) {
    408 		pu->pu_ml_timep = NULL;
    409 	} else {
    410 		pu->pu_ml_timeout = *ts;
    411 		pu->pu_ml_timep = &pu->pu_ml_timeout;
    412 	}
    413 }
    414 
    415 void
    416 puffs_set_prepost(struct puffs_usermount *pu,
    417 	pu_prepost_fn pre, pu_prepost_fn pst)
    418 {
    419 
    420 	pu->pu_oppre = pre;
    421 	pu->pu_oppost = pst;
    422 }
    423 
    424 void
    425 puffs_setback(struct puffs_cc *pcc, int whatback)
    426 {
    427 	struct puffs_req *preq = puffs__framebuf_getdataptr(pcc->pcc_pb);
    428 
    429 	assert(PUFFSOP_OPCLASS(preq->preq_opclass) == PUFFSOP_VN && (
    430 	    preq->preq_optype == PUFFS_VN_OPEN ||
    431 	    preq->preq_optype == PUFFS_VN_MMAP ||
    432 	    preq->preq_optype == PUFFS_VN_REMOVE ||
    433 	    preq->preq_optype == PUFFS_VN_RMDIR ||
    434 	    preq->preq_optype == PUFFS_VN_INACTIVE));
    435 
    436 	preq->preq_setbacks |= whatback & PUFFS_SETBACK_MASK;
    437 }
    438 
    439 int
    440 puffs_daemon(struct puffs_usermount *pu, int nochdir, int noclose)
    441 {
    442 	long int n;
    443 	int parent, value, fd;
    444 
    445 	if (pipe(pu->pu_dpipe) == -1)
    446 		return -1;
    447 
    448 	switch (fork()) {
    449 	case -1:
    450 		return -1;
    451 	case 0:
    452 		parent = 0;
    453 		break;
    454 	default:
    455 		parent = 1;
    456 		break;
    457 	}
    458 	pu->pu_state |= PU_PUFFSDAEMON;
    459 
    460 	if (parent) {
    461 		close(pu->pu_dpipe[1]);
    462 		n = read(pu->pu_dpipe[0], &value, sizeof(int));
    463 		if (n == -1)
    464 			err(1, "puffs_daemon");
    465 		if (n != sizeof(value))
    466 			errx(1, "puffs_daemon got %ld bytes", n);
    467 		if (value) {
    468 			errno = value;
    469 			err(1, "puffs_daemon");
    470 		}
    471 		exit(0);
    472 	} else {
    473 		if (setsid() == -1)
    474 			goto fail;
    475 
    476 		if (!nochdir)
    477 			chdir("/");
    478 
    479 		if (!noclose) {
    480 			fd = open(_PATH_DEVNULL, O_RDWR, 0);
    481 			if (fd == -1)
    482 				goto fail;
    483 			dup2(fd, STDIN_FILENO);
    484 			dup2(fd, STDOUT_FILENO);
    485 			dup2(fd, STDERR_FILENO);
    486 			if (fd > STDERR_FILENO)
    487 				close(fd);
    488 		}
    489 		return 0;
    490 	}
    491 
    492  fail:
    493 	n = write(pu->pu_dpipe[1], &errno, sizeof(int));
    494 	assert(n == 4);
    495 	return -1;
    496 }
    497 
    498 static void
    499 shutdaemon(struct puffs_usermount *pu, int error)
    500 {
    501 	ssize_t n;
    502 
    503 	n = write(pu->pu_dpipe[1], &error, sizeof(int));
    504 	assert(n == 4);
    505 	close(pu->pu_dpipe[0]);
    506 	close(pu->pu_dpipe[1]);
    507 	pu->pu_state &= ~PU_PUFFSDAEMON;
    508 }
    509 
    510 int
    511 puffs_mount(struct puffs_usermount *pu, const char *dir, int mntflags,
    512 	puffs_cookie_t cookie)
    513 {
    514 	int rv, fd, sverrno;
    515 	char *comfd;
    516 
    517 	pu->pu_kargp->pa_root_cookie = cookie;
    518 
    519 	/* XXXkludgehere */
    520 	/* kauth doesn't provide this service any longer */
    521 	if (geteuid() != 0)
    522 		mntflags |= MNT_NOSUID | MNT_NODEV;
    523 
    524 	/*
    525 	 * Undocumented...  Well, documented only here.
    526 	 *
    527 	 * This is used for imaginative purposes.  If the env variable is
    528 	 * set, puffs_mount() doesn't do the regular mount procedure.
    529 	 * Rather, it crams the mount data down the comfd and sets comfd as
    530 	 * the puffs descriptor.
    531 	 *
    532 	 * This shouldn't be used unless you can read my mind ( ... or write
    533 	 * it, not to mention execute it, but that's starting to get silly).
    534 	 */
    535 	if ((comfd = getenv("PUFFS_COMFD")) != NULL) {
    536 		size_t len;
    537 
    538 		if (sscanf(comfd, "%d", &pu->pu_fd) != 1) {
    539 			errno = EINVAL;
    540 			rv = -1;
    541 			goto out;
    542 		}
    543 		/* check that what we got at least resembles an fd */
    544 		if (fcntl(pu->pu_fd, F_GETFL) == -1) {
    545 			rv = -1;
    546 			goto out;
    547 		}
    548 
    549 #define allwrite(buf, len)						\
    550 do {									\
    551 	ssize_t al_rv;							\
    552 	al_rv = write(pu->pu_fd, buf, len);				\
    553 	if ((size_t)al_rv != len) {					\
    554 		if (al_rv != -1)					\
    555 			errno = EIO;					\
    556 		rv = -1;						\
    557 		goto out;						\
    558 	}								\
    559 } while (/*CONSTCOND*/0)
    560 		len = strlen(dir)+1;
    561 		allwrite(&len, sizeof(len));
    562 		allwrite(dir, len);
    563 		len = strlen(pu->pu_kargp->pa_mntfromname)+1;
    564 		allwrite(&len, sizeof(len));
    565 		allwrite(pu->pu_kargp->pa_mntfromname, len);
    566 		allwrite(&mntflags, sizeof(mntflags));
    567 		len = sizeof(*pu->pu_kargp);
    568 		allwrite(&len, sizeof(len));
    569 		allwrite(pu->pu_kargp, sizeof(*pu->pu_kargp));
    570 		allwrite(&pu->pu_flags, sizeof(pu->pu_flags));
    571 #undef allwrite
    572 
    573 		rv = 0;
    574 	} else {
    575 		char rp[MAXPATHLEN];
    576 
    577 		if (realpath(dir, rp) == NULL) {
    578 			rv = -1;
    579 			goto out;
    580 		}
    581 
    582 		if (strcmp(dir, rp) != 0) {
    583 			warnx("puffs_mount: \"%s\" is a relative path.", dir);
    584 			warnx("puffs_mount: using \"%s\" instead.", rp);
    585 		}
    586 
    587 		fd = open(_PATH_PUFFS, O_RDWR);
    588 		if (fd == -1) {
    589 			warnx("puffs_mount: cannot open %s", _PATH_PUFFS);
    590 			rv = -1;
    591 			goto out;
    592 		}
    593 		if (fd <= 2)
    594 			warnx("puffs_mount: device fd %d (<= 2), sure this is "
    595 			    "what you want?", fd);
    596 
    597 		pu->pu_kargp->pa_fd = pu->pu_fd = fd;
    598 		if ((rv = mount(MOUNT_PUFFS, rp, mntflags,
    599 		    pu->pu_kargp, sizeof(struct puffs_kargs))) == -1)
    600 			goto out;
    601 	}
    602 
    603 	PU_SETSTATE(pu, PUFFS_STATE_RUNNING);
    604 
    605  out:
    606 	if (rv != 0)
    607 		sverrno = errno;
    608 	else
    609 		sverrno = 0;
    610 	free(pu->pu_kargp);
    611 	pu->pu_kargp = NULL;
    612 
    613 	if (pu->pu_state & PU_PUFFSDAEMON)
    614 		shutdaemon(pu, sverrno);
    615 
    616 	errno = sverrno;
    617 	return rv;
    618 }
    619 
    620 struct puffs_usermount *
    621 puffs_init(struct puffs_ops *pops, const char *mntfromname,
    622 	const char *puffsname, void *priv, uint32_t pflags)
    623 {
    624 	struct puffs_usermount *pu;
    625 	struct puffs_kargs *pargs;
    626 	int sverrno;
    627 
    628 	if (puffsname == PUFFS_DEFER)
    629 		puffsname = "n/a";
    630 	if (mntfromname == PUFFS_DEFER)
    631 		mntfromname = "n/a";
    632 	if (priv == PUFFS_DEFER)
    633 		priv = NULL;
    634 
    635 	pu = malloc(sizeof(struct puffs_usermount));
    636 	if (pu == NULL)
    637 		goto failfree;
    638 	memset(pu, 0, sizeof(struct puffs_usermount));
    639 
    640 	pargs = pu->pu_kargp = malloc(sizeof(struct puffs_kargs));
    641 	if (pargs == NULL)
    642 		goto failfree;
    643 	memset(pargs, 0, sizeof(struct puffs_kargs));
    644 
    645 	pargs->pa_vers = PUFFSVERSION;
    646 	pargs->pa_flags = PUFFS_FLAG_KERN(pflags);
    647 	fillvnopmask(pops, pargs);
    648 	puffs_setmntinfo(pu, mntfromname, puffsname);
    649 
    650 	puffs_zerostatvfs(&pargs->pa_svfsb);
    651 	pargs->pa_root_cookie = NULL;
    652 	pargs->pa_root_vtype = VDIR;
    653 	pargs->pa_root_vsize = 0;
    654 	pargs->pa_root_rdev = 0;
    655 	pargs->pa_maxmsglen = 0;
    656 	if (/*CONSTCOND*/ sizeof(time_t) == 4)
    657 		pargs->pa_time32 = 1;
    658 	else
    659 		pargs->pa_time32 = 0;
    660 
    661 	pu->pu_flags = pflags;
    662 	pu->pu_ops = *pops;
    663 	free(pops); /* XXX */
    664 
    665 	pu->pu_privdata = priv;
    666 	pu->pu_cc_stackshift = PUFFS_CC_STACKSHIFT_DEFAULT;
    667 	LIST_INIT(&pu->pu_pnodelst);
    668 	LIST_INIT(&pu->pu_ios);
    669 	LIST_INIT(&pu->pu_ios_rmlist);
    670 	LIST_INIT(&pu->pu_ccmagazin);
    671 	TAILQ_INIT(&pu->pu_sched);
    672 
    673 	pu->pu_framectrl[PU_FRAMECTRL_FS].rfb = puffs__fsframe_read;
    674 	pu->pu_framectrl[PU_FRAMECTRL_FS].wfb = puffs__fsframe_write;
    675 	pu->pu_framectrl[PU_FRAMECTRL_FS].cmpfb = puffs__fsframe_cmp;
    676 	pu->pu_framectrl[PU_FRAMECTRL_FS].gotfb = puffs__fsframe_gotframe;
    677 	pu->pu_framectrl[PU_FRAMECTRL_FS].fdnotfn = puffs_framev_unmountonclose;
    678 
    679 	/* defaults for some user-settable translation functions */
    680 	pu->pu_cmap = NULL; /* identity translation */
    681 
    682 	pu->pu_pathbuild = puffs_stdpath_buildpath;
    683 	pu->pu_pathfree = puffs_stdpath_freepath;
    684 	pu->pu_pathcmp = puffs_stdpath_cmppath;
    685 	pu->pu_pathtransform = NULL;
    686 	pu->pu_namemod = NULL;
    687 
    688 	pu->pu_errnotify = puffs_kernerr_log;
    689 
    690 	PU_SETSTATE(pu, PUFFS_STATE_BEFOREMOUNT);
    691 
    692 	return pu;
    693 
    694  failfree:
    695 	/* can't unmount() from here for obvious reasons */
    696 	sverrno = errno;
    697 	free(pu);
    698 	errno = sverrno;
    699 	return NULL;
    700 }
    701 
    702 void
    703 puffs_cancel(struct puffs_usermount *pu, int error)
    704 {
    705 
    706 	assert(puffs_getstate(pu) < PUFFS_STATE_RUNNING);
    707 	shutdaemon(pu, error);
    708 	free(pu);
    709 }
    710 
    711 /*ARGSUSED1*/
    712 int
    713 puffs_exit(struct puffs_usermount *pu, int unused /* strict compat */)
    714 {
    715 	struct puffs_framebuf *pb;
    716 	struct puffs_req *preq;
    717 	void *winp;
    718 	size_t winlen;
    719 	int sverrno;
    720 
    721 	pb = puffs_framebuf_make();
    722 	if (pb == NULL) {
    723 		errno = ENOMEM;
    724 		return -1;
    725 	}
    726 
    727 	winlen = sizeof(struct puffs_req);
    728 	if (puffs_framebuf_getwindow(pb, 0, &winp, &winlen) == -1) {
    729 		sverrno = errno;
    730 		puffs_framebuf_destroy(pb);
    731 		errno = sverrno;
    732 		return -1;
    733 	}
    734 	preq = winp;
    735 
    736 	preq->preq_buflen = sizeof(struct puffs_req);
    737 	preq->preq_opclass = PUFFSOP_UNMOUNT;
    738 	preq->preq_id = puffs__nextreq(pu);
    739 
    740 	puffs_framev_enqueue_justsend(pu, puffs_getselectable(pu), pb, 1, 0);
    741 
    742 	return 0;
    743 }
    744 
    745 /* no sigset_t static intializer */
    746 static int sigs[NSIG] = { 0, };
    747 static int sigcatch = 0;
    748 
    749 int
    750 puffs_unmountonsignal(int sig, bool sigignore)
    751 {
    752 
    753 	if (sig < 0 || sig >= (int)NSIG) {
    754 		errno = EINVAL;
    755 		return -1;
    756 	}
    757 	if (sigignore)
    758 		if (signal(sig, SIG_IGN) == SIG_ERR)
    759 			return -1;
    760 
    761 	if (!sigs[sig])
    762 		sigcatch++;
    763 	sigs[sig] = 1;
    764 
    765 	return 0;
    766 }
    767 
    768 /*
    769  * Actual mainloop.  This is called from a context which can block.
    770  * It is called either from puffs_mainloop (indirectly, via
    771  * puffs_cc_continue() or from puffs_cc_yield()).
    772  */
    773 void
    774 puffs__theloop(struct puffs_cc *pcc)
    775 {
    776 	struct puffs_usermount *pu = pcc->pcc_pu;
    777 	struct puffs_framectrl *pfctrl;
    778 	struct puffs_fctrl_io *fio;
    779 	struct kevent *curev;
    780 	size_t nchanges;
    781 	int ndone;
    782 
    783 	while (puffs_getstate(pu) != PUFFS_STATE_UNMOUNTED) {
    784 
    785 		/*
    786 		 * Schedule existing requests.
    787 		 */
    788 		while ((pcc = TAILQ_FIRST(&pu->pu_sched)) != NULL) {
    789 			TAILQ_REMOVE(&pu->pu_sched, pcc, pcc_schedent);
    790 			puffs__goto(pcc);
    791 		}
    792 
    793 		if (pu->pu_ml_lfn)
    794 			pu->pu_ml_lfn(pu);
    795 
    796 		/* XXX: can we still do these optimizations? */
    797 #if 0
    798 		/*
    799 		 * Do this here, because:
    800 		 *  a) loopfunc might generate some results
    801 		 *  b) it's still "after" event handling (except for round 1)
    802 		 */
    803 		if (puffs_req_putput(ppr) == -1)
    804 			goto out;
    805 		puffs_req_resetput(ppr);
    806 
    807 		/* micro optimization: skip kevent syscall if possible */
    808 		if (pu->pu_nfds == 1 && pu->pu_ml_timep == NULL
    809 		    && (pu->pu_state & PU_ASYNCFD) == 0) {
    810 			pfctrl = XXX->fctrl;
    811 			puffs_framev_input(pu, pfctrl, XXX);
    812 			continue;
    813 		}
    814 #endif
    815 
    816 		/* else: do full processing */
    817 		/* Don't bother worrying about O(n) for now */
    818 		LIST_FOREACH(fio, &pu->pu_ios, fio_entries) {
    819 			if (fio->stat & FIO_WRGONE)
    820 				continue;
    821 
    822 			pfctrl = fio->fctrl;
    823 
    824 			/*
    825 			 * Try to write out everything to avoid the
    826 			 * need for enabling EVFILT_WRITE.  The likely
    827 			 * case is that we can fit everything into the
    828 			 * socket buffer.
    829 			 */
    830 			puffs__framev_output(pu, pfctrl, fio);
    831 		}
    832 
    833 		/*
    834 		 * Build list of which to enable/disable in writecheck.
    835 		 */
    836 		nchanges = 0;
    837 		LIST_FOREACH(fio, &pu->pu_ios, fio_entries) {
    838 			if (fio->stat & FIO_WRGONE)
    839 				continue;
    840 
    841 			/* en/disable write checks for kqueue as needed */
    842 			assert((FIO_EN_WRITE(fio) && FIO_RM_WRITE(fio)) == 0);
    843 			if (FIO_EN_WRITE(fio)) {
    844 				EV_SET(&pu->pu_evs[nchanges], fio->io_fd,
    845 				    EVFILT_WRITE, EV_ENABLE, 0, 0,
    846 				    (uintptr_t)fio);
    847 				fio->stat |= FIO_WR;
    848 				nchanges++;
    849 			}
    850 			if (FIO_RM_WRITE(fio)) {
    851 				EV_SET(&pu->pu_evs[nchanges], fio->io_fd,
    852 				    EVFILT_WRITE, EV_DISABLE, 0, 0,
    853 				    (uintptr_t)fio);
    854 				fio->stat &= ~FIO_WR;
    855 				nchanges++;
    856 			}
    857 		}
    858 
    859 		ndone = kevent(pu->pu_kq, pu->pu_evs, nchanges,
    860 		    pu->pu_evs, pu->pu_nevs, pu->pu_ml_timep);
    861 
    862 		if (ndone == -1) {
    863 			if (errno != EINTR)
    864 				break;
    865 			else
    866 				continue;
    867 		}
    868 
    869 		/* uoptimize */
    870 		if (ndone == 0)
    871 			continue;
    872 
    873 		/* iterate over the results */
    874 		for (curev = pu->pu_evs; ndone--; curev++) {
    875 			int what;
    876 
    877 #if 0
    878 			/* get & possibly dispatch events from kernel */
    879 			if (curev->ident == puffsfd) {
    880 				if (puffs_req_handle(pgr, ppr, 0) == -1)
    881 					goto out;
    882 				continue;
    883 			}
    884 #endif
    885 
    886 			fio = (void *)curev->udata;
    887 			if (__predict_true(fio))
    888 				pfctrl = fio->fctrl;
    889 			else
    890 				pfctrl = NULL;
    891 			if (curev->flags & EV_ERROR) {
    892 				assert(curev->filter == EVFILT_WRITE);
    893 				fio->stat &= ~FIO_WR;
    894 
    895 				/* XXX: how to know if it's a transient error */
    896 				puffs__framev_writeclose(pu, fio,
    897 				    (int)curev->data);
    898 				puffs__framev_notify(fio, PUFFS_FBIO_ERROR);
    899 				continue;
    900 			}
    901 
    902 			what = 0;
    903 			if (curev->filter == EVFILT_READ) {
    904 				puffs__framev_input(pu, pfctrl, fio);
    905 				what |= PUFFS_FBIO_READ;
    906 			}
    907 
    908 			else if (curev->filter == EVFILT_WRITE) {
    909 				puffs__framev_output(pu, pfctrl, fio);
    910 				what |= PUFFS_FBIO_WRITE;
    911 			}
    912 
    913 			else if (__predict_false(curev->filter==EVFILT_SIGNAL)){
    914 				if ((pu->pu_state & PU_DONEXIT) == 0) {
    915 					PU_SETSFLAG(pu, PU_DONEXIT);
    916 					puffs_exit(pu, 0);
    917 				}
    918 			}
    919 			if (what)
    920 				puffs__framev_notify(fio, what);
    921 		}
    922 
    923 		/*
    924 		 * Really free fd's now that we don't have references
    925 		 * to them.
    926 		 */
    927 		while ((fio = LIST_FIRST(&pu->pu_ios_rmlist)) != NULL) {
    928 			LIST_REMOVE(fio, fio_entries);
    929 			free(fio);
    930 		}
    931 	}
    932 
    933 	if (puffs__cc_restoremain(pu) == -1)
    934 		warn("cannot restore main context.  impending doom");
    935 }
    936 int
    937 puffs_mainloop(struct puffs_usermount *pu)
    938 {
    939 	struct puffs_fctrl_io *fio;
    940 	struct puffs_cc *pcc;
    941 	struct kevent *curev;
    942 	size_t nevs;
    943 	int sverrno, i;
    944 
    945 	assert(puffs_getstate(pu) >= PUFFS_STATE_RUNNING);
    946 
    947 	pu->pu_kq = kqueue();
    948 	if (pu->pu_kq == -1)
    949 		goto out;
    950 	pu->pu_state |= PU_HASKQ;
    951 
    952 	puffs_setblockingmode(pu, PUFFSDEV_NONBLOCK);
    953 	if (puffs__framev_addfd_ctrl(pu, puffs_getselectable(pu),
    954 	    PUFFS_FBIO_READ | PUFFS_FBIO_WRITE,
    955 	    &pu->pu_framectrl[PU_FRAMECTRL_FS]) == -1)
    956 		goto out;
    957 
    958 	nevs = pu->pu_nevs + sigcatch;
    959 	curev = realloc(pu->pu_evs, nevs * sizeof(struct kevent));
    960 	if (curev == NULL)
    961 		goto out;
    962 	pu->pu_evs = curev;
    963 	pu->pu_nevs = nevs;
    964 
    965 	LIST_FOREACH(fio, &pu->pu_ios, fio_entries) {
    966 		EV_SET(curev, fio->io_fd, EVFILT_READ, EV_ADD,
    967 		    0, 0, (uintptr_t)fio);
    968 		curev++;
    969 		EV_SET(curev, fio->io_fd, EVFILT_WRITE, EV_ADD | EV_DISABLE,
    970 		    0, 0, (uintptr_t)fio);
    971 		curev++;
    972 	}
    973 	for (i = 0; i < NSIG; i++) {
    974 		if (sigs[i]) {
    975 			EV_SET(curev, i, EVFILT_SIGNAL, EV_ADD | EV_ENABLE,
    976 			    0, 0, 0);
    977 			curev++;
    978 		}
    979 	}
    980 	assert(curev - pu->pu_evs == (ssize_t)pu->pu_nevs);
    981 	if (kevent(pu->pu_kq, pu->pu_evs, pu->pu_nevs, NULL, 0, NULL) == -1)
    982 		goto out;
    983 
    984 	pu->pu_state |= PU_INLOOP;
    985 
    986 	/*
    987 	 * Create alternate execution context and jump to it.  Note
    988 	 * that we come "out" of savemain twice.  Where we come out
    989 	 * of it depends on the architecture.  If the return address is
    990 	 * stored on the stack, we jump out from puffs_cc_continue(),
    991 	 * for a register return address from puffs__cc_savemain().
    992 	 * PU_MAINRESTORE makes sure we DTRT in both cases.
    993 	 */
    994 	if (puffs__cc_create(pu, puffs__theloop, &pcc) == -1) {
    995 		goto out;
    996 	}
    997 	if (puffs__cc_savemain(pu) == -1) {
    998 		goto out;
    999 	}
   1000 	if ((pu->pu_state & PU_MAINRESTORE) == 0)
   1001 		puffs_cc_continue(pcc);
   1002 
   1003 	finalpush(pu);
   1004 	errno = 0;
   1005 
   1006  out:
   1007 	/* store the real error for a while */
   1008 	sverrno = errno;
   1009 
   1010 	errno = sverrno;
   1011 	if (errno)
   1012 		return -1;
   1013 	else
   1014 		return 0;
   1015 }
   1016