xref: /freebsd/sys/compat/linux/linux.c (revision fbf05d2147b1add8b760be166c4b1fd4499ebce8)
1 /*-
2  * Copyright (c) 2015 Dmitry Chagin <dchagin@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include "opt_inet6.h"
27 
28 #include <sys/param.h>
29 #include <sys/conf.h>
30 #include <sys/ctype.h>
31 #include <sys/file.h>
32 #include <sys/filedesc.h>
33 #include <sys/jail.h>
34 #include <sys/limits.h>
35 #include <sys/lock.h>
36 #include <sys/malloc.h>
37 #include <sys/poll.h>
38 #include <sys/proc.h>
39 #include <sys/signalvar.h>
40 #include <sys/socket.h>
41 #include <sys/socketvar.h>
42 
43 #include <netlink/netlink.h>
44 #include <sys/un.h>
45 #include <netinet/in.h>
46 
47 #include <compat/linux/linux.h>
48 #include <compat/linux/linux_common.h>
49 #include <compat/linux/linux_mib.h>
50 #include <compat/linux/linux_util.h>
51 
52 _Static_assert(sizeof(struct sockaddr) == sizeof(struct l_sockaddr),
53     "Linux struct sockaddr size");
54 _Static_assert(offsetof(struct sockaddr, sa_data) ==
55     offsetof(struct l_sockaddr, sa_data), "Linux struct sockaddr layout");
56 
57 static int bsd_to_linux_sigtbl[LINUX_SIGTBLSZ] = {
58 	LINUX_SIGHUP,	/* SIGHUP */
59 	LINUX_SIGINT,	/* SIGINT */
60 	LINUX_SIGQUIT,	/* SIGQUIT */
61 	LINUX_SIGILL,	/* SIGILL */
62 	LINUX_SIGTRAP,	/* SIGTRAP */
63 	LINUX_SIGABRT,	/* SIGABRT */
64 	0,		/* SIGEMT */
65 	LINUX_SIGFPE,	/* SIGFPE */
66 	LINUX_SIGKILL,	/* SIGKILL */
67 	LINUX_SIGBUS,	/* SIGBUS */
68 	LINUX_SIGSEGV,	/* SIGSEGV */
69 	LINUX_SIGSYS,	/* SIGSYS */
70 	LINUX_SIGPIPE,	/* SIGPIPE */
71 	LINUX_SIGALRM,	/* SIGALRM */
72 	LINUX_SIGTERM,	/* SIGTERM */
73 	LINUX_SIGURG,	/* SIGURG */
74 	LINUX_SIGSTOP,	/* SIGSTOP */
75 	LINUX_SIGTSTP,	/* SIGTSTP */
76 	LINUX_SIGCONT,	/* SIGCONT */
77 	LINUX_SIGCHLD,	/* SIGCHLD */
78 	LINUX_SIGTTIN,	/* SIGTTIN */
79 	LINUX_SIGTTOU,	/* SIGTTOU */
80 	LINUX_SIGIO,	/* SIGIO */
81 	LINUX_SIGXCPU,	/* SIGXCPU */
82 	LINUX_SIGXFSZ,	/* SIGXFSZ */
83 	LINUX_SIGVTALRM,/* SIGVTALRM */
84 	LINUX_SIGPROF,	/* SIGPROF */
85 	LINUX_SIGWINCH,	/* SIGWINCH */
86 	0,		/* SIGINFO */
87 	LINUX_SIGUSR1,	/* SIGUSR1 */
88 	LINUX_SIGUSR2	/* SIGUSR2 */
89 };
90 
91 #define	LINUX_SIGPWREMU	(SIGRTMIN + (LINUX_SIGRTMAX - LINUX_SIGRTMIN) + 1)
92 
93 static int linux_to_bsd_sigtbl[LINUX_SIGTBLSZ] = {
94 	SIGHUP,		/* LINUX_SIGHUP */
95 	SIGINT,		/* LINUX_SIGINT */
96 	SIGQUIT,	/* LINUX_SIGQUIT */
97 	SIGILL,		/* LINUX_SIGILL */
98 	SIGTRAP,	/* LINUX_SIGTRAP */
99 	SIGABRT,	/* LINUX_SIGABRT */
100 	SIGBUS,		/* LINUX_SIGBUS */
101 	SIGFPE,		/* LINUX_SIGFPE */
102 	SIGKILL,	/* LINUX_SIGKILL */
103 	SIGUSR1,	/* LINUX_SIGUSR1 */
104 	SIGSEGV,	/* LINUX_SIGSEGV */
105 	SIGUSR2,	/* LINUX_SIGUSR2 */
106 	SIGPIPE,	/* LINUX_SIGPIPE */
107 	SIGALRM,	/* LINUX_SIGALRM */
108 	SIGTERM,	/* LINUX_SIGTERM */
109 	SIGBUS,		/* LINUX_SIGSTKFLT */
110 	SIGCHLD,	/* LINUX_SIGCHLD */
111 	SIGCONT,	/* LINUX_SIGCONT */
112 	SIGSTOP,	/* LINUX_SIGSTOP */
113 	SIGTSTP,	/* LINUX_SIGTSTP */
114 	SIGTTIN,	/* LINUX_SIGTTIN */
115 	SIGTTOU,	/* LINUX_SIGTTOU */
116 	SIGURG,		/* LINUX_SIGURG */
117 	SIGXCPU,	/* LINUX_SIGXCPU */
118 	SIGXFSZ,	/* LINUX_SIGXFSZ */
119 	SIGVTALRM,	/* LINUX_SIGVTALARM */
120 	SIGPROF,	/* LINUX_SIGPROF */
121 	SIGWINCH,	/* LINUX_SIGWINCH */
122 	SIGIO,		/* LINUX_SIGIO */
123 	/*
124 	 * FreeBSD does not have SIGPWR signal, map Linux SIGPWR signal
125 	 * to the first unused FreeBSD signal number. Since Linux supports
126 	 * signals from 1 to 64 we are ok here as our SIGRTMIN = 65.
127 	 */
128 	LINUX_SIGPWREMU,/* LINUX_SIGPWR */
129 	SIGSYS		/* LINUX_SIGSYS */
130 };
131 
132 static struct cdev *dev_shm_cdev;
133 static struct cdevsw dev_shm_cdevsw = {
134      .d_version = D_VERSION,
135      .d_name    = "dev_shm",
136 };
137 
138 /*
139  * Map Linux RT signals to the FreeBSD RT signals.
140  */
141 static inline int
linux_to_bsd_rt_signal(int sig)142 linux_to_bsd_rt_signal(int sig)
143 {
144 
145 	return (SIGRTMIN + sig - LINUX_SIGRTMIN);
146 }
147 
148 static inline int
bsd_to_linux_rt_signal(int sig)149 bsd_to_linux_rt_signal(int sig)
150 {
151 
152 	return (sig - SIGRTMIN + LINUX_SIGRTMIN);
153 }
154 
155 int
linux_to_bsd_signal(int sig)156 linux_to_bsd_signal(int sig)
157 {
158 
159 	KASSERT(sig > 0 && sig <= LINUX_SIGRTMAX, ("invalid Linux signal %d\n", sig));
160 
161 	if (sig < LINUX_SIGRTMIN)
162 		return (linux_to_bsd_sigtbl[_SIG_IDX(sig)]);
163 
164 	return (linux_to_bsd_rt_signal(sig));
165 }
166 
167 int
bsd_to_linux_signal(int sig)168 bsd_to_linux_signal(int sig)
169 {
170 
171 	if (sig <= LINUX_SIGTBLSZ)
172 		return (bsd_to_linux_sigtbl[_SIG_IDX(sig)]);
173 	if (sig == LINUX_SIGPWREMU)
174 		return (LINUX_SIGPWR);
175 
176 	return (bsd_to_linux_rt_signal(sig));
177 }
178 
179 int
linux_to_bsd_sigaltstack(int lsa)180 linux_to_bsd_sigaltstack(int lsa)
181 {
182 	int bsa = 0;
183 
184 	if (lsa & LINUX_SS_DISABLE)
185 		bsa |= SS_DISABLE;
186 	/*
187 	 * Linux ignores SS_ONSTACK flag for ss
188 	 * parameter while FreeBSD prohibits it.
189 	 */
190 	return (bsa);
191 }
192 
193 int
bsd_to_linux_sigaltstack(int bsa)194 bsd_to_linux_sigaltstack(int bsa)
195 {
196 	int lsa = 0;
197 
198 	if (bsa & SS_DISABLE)
199 		lsa |= LINUX_SS_DISABLE;
200 	if (bsa & SS_ONSTACK)
201 		lsa |= LINUX_SS_ONSTACK;
202 	return (lsa);
203 }
204 
205 void
linux_to_bsd_sigset(l_sigset_t * lss,sigset_t * bss)206 linux_to_bsd_sigset(l_sigset_t *lss, sigset_t *bss)
207 {
208 	int b, l;
209 
210 	SIGEMPTYSET(*bss);
211 	for (l = 1; l <= LINUX_SIGRTMAX; l++) {
212 		if (LINUX_SIGISMEMBER(*lss, l)) {
213 			b = linux_to_bsd_signal(l);
214 			if (b)
215 				SIGADDSET(*bss, b);
216 		}
217 	}
218 }
219 
220 void
bsd_to_linux_sigset(sigset_t * bss,l_sigset_t * lss)221 bsd_to_linux_sigset(sigset_t *bss, l_sigset_t *lss)
222 {
223 	int b, l;
224 
225 	LINUX_SIGEMPTYSET(*lss);
226 	for (b = 1; b <= SIGRTMAX; b++) {
227 		if (SIGISMEMBER(*bss, b)) {
228 			l = bsd_to_linux_signal(b);
229 			if (l)
230 				LINUX_SIGADDSET(*lss, l);
231 		}
232 	}
233 }
234 
235 sa_family_t
linux_to_bsd_domain(sa_family_t domain)236 linux_to_bsd_domain(sa_family_t domain)
237 {
238 
239 	switch (domain) {
240 	case LINUX_AF_UNSPEC:
241 		return (AF_UNSPEC);
242 	case LINUX_AF_UNIX:
243 		return (AF_LOCAL);
244 	case LINUX_AF_INET:
245 		return (AF_INET);
246 	case LINUX_AF_INET6:
247 		return (AF_INET6);
248 	case LINUX_AF_AX25:
249 		return (AF_CCITT);
250 	case LINUX_AF_IPX:
251 		return (AF_IPX);
252 	case LINUX_AF_APPLETALK:
253 		return (AF_APPLETALK);
254 	case LINUX_AF_NETLINK:
255 		return (AF_NETLINK);
256 	}
257 	return (AF_UNKNOWN);
258 }
259 
260 sa_family_t
bsd_to_linux_domain(sa_family_t domain)261 bsd_to_linux_domain(sa_family_t domain)
262 {
263 
264 	switch (domain) {
265 	case AF_UNSPEC:
266 		return (LINUX_AF_UNSPEC);
267 	case AF_LOCAL:
268 		return (LINUX_AF_UNIX);
269 	case AF_INET:
270 		return (LINUX_AF_INET);
271 	case AF_INET6:
272 		return (LINUX_AF_INET6);
273 	case AF_CCITT:
274 		return (LINUX_AF_AX25);
275 	case AF_IPX:
276 		return (LINUX_AF_IPX);
277 	case AF_APPLETALK:
278 		return (LINUX_AF_APPLETALK);
279 	case AF_NETLINK:
280 		return (LINUX_AF_NETLINK);
281 	}
282 	return (AF_UNKNOWN);
283 }
284 
285 /*
286  * Based on the fact that:
287  * 1. Native and Linux storage of struct sockaddr
288  * and struct sockaddr_in6 are equal.
289  * 2. On Linux sa_family is the first member of all struct sockaddr.
290  */
291 int
bsd_to_linux_sockaddr(const struct sockaddr * sa,struct l_sockaddr ** lsa,socklen_t len)292 bsd_to_linux_sockaddr(const struct sockaddr *sa, struct l_sockaddr **lsa,
293     socklen_t len)
294 {
295 	struct l_sockaddr *kosa;
296 	sa_family_t bdom;
297 
298 	*lsa = NULL;
299 	if (len < 2 || len > UCHAR_MAX)
300 		return (EINVAL);
301 	bdom = bsd_to_linux_domain(sa->sa_family);
302 	if (bdom == AF_UNKNOWN)
303 		return (EAFNOSUPPORT);
304 
305 	kosa = malloc(len, M_LINUX, M_WAITOK);
306 	bcopy(sa, kosa, len);
307 	kosa->sa_family = bdom;
308 	*lsa = kosa;
309 	return (0);
310 }
311 
312 /*
313  * If sap is NULL, then osa points at already copied in linux sockaddr that
314  * should be edited in place.  Otherwise memory is allocated, sockaddr
315  * copied in and returned in *sap.
316  */
317 int
linux_to_bsd_sockaddr(struct l_sockaddr * osa,struct sockaddr ** sap,socklen_t * len)318 linux_to_bsd_sockaddr(struct l_sockaddr *osa, struct sockaddr **sap,
319     socklen_t *len)
320 {
321 	struct sockaddr *sa;
322 	struct l_sockaddr *kosa;
323 #ifdef INET6
324 	struct sockaddr_in6 *sin6;
325 	bool  oldv6size;
326 #endif
327 	char *name;
328 	int salen, bdom, error, hdrlen, namelen;
329 
330 	if (*len < 2 || *len > UCHAR_MAX)
331 		return (EINVAL);
332 
333 	salen = *len;
334 
335 #ifdef INET6
336 	oldv6size = false;
337 	/*
338 	 * Check for old (pre-RFC2553) sockaddr_in6. We may accept it
339 	 * if it's a v4-mapped address, so reserve the proper space
340 	 * for it.
341 	 */
342 	if (salen == sizeof(struct sockaddr_in6) - sizeof(uint32_t)) {
343 		salen += sizeof(uint32_t);
344 		oldv6size = true;
345 	}
346 #endif
347 
348 	if (sap != NULL) {
349 		kosa = malloc(salen, M_SONAME, M_WAITOK);
350 		if ((error = copyin(osa, kosa, *len)))
351 			goto out;
352 	} else
353 		kosa = osa;
354 
355 	bdom = linux_to_bsd_domain(kosa->sa_family);
356 	if (bdom == AF_UNKNOWN) {
357 		error = EAFNOSUPPORT;
358 		goto out;
359 	}
360 
361 #ifdef INET6
362 	/*
363 	 * Older Linux IPv6 code uses obsolete RFC2133 struct sockaddr_in6,
364 	 * which lacks the scope id compared with RFC2553 one. If we detect
365 	 * the situation, reject the address and write a message to system log.
366 	 *
367 	 * Still accept addresses for which the scope id is not used.
368 	 */
369 	if (oldv6size) {
370 		if (bdom == AF_INET6) {
371 			sin6 = (struct sockaddr_in6 *)kosa;
372 			if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr) ||
373 			    (!IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) &&
374 			     !IN6_IS_ADDR_SITELOCAL(&sin6->sin6_addr) &&
375 			     !IN6_IS_ADDR_V4COMPAT(&sin6->sin6_addr) &&
376 			     !IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr) &&
377 			     !IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))) {
378 				sin6->sin6_scope_id = 0;
379 			} else {
380 				linux_msg(curthread,
381 				    "obsolete pre-RFC2553 sockaddr_in6 rejected");
382 				error = EINVAL;
383 				goto out;
384 			}
385 		} else
386 			salen -= sizeof(uint32_t);
387 	}
388 #endif
389 	if (bdom == AF_INET) {
390 		if (salen < sizeof(struct sockaddr_in)) {
391 			error = EINVAL;
392 			goto out;
393 		}
394 		salen = sizeof(struct sockaddr_in);
395 	}
396 
397 	if (bdom == AF_LOCAL && salen > sizeof(struct sockaddr_un)) {
398 		hdrlen = offsetof(struct sockaddr_un, sun_path);
399 		name = ((struct sockaddr_un *)kosa)->sun_path;
400 		if (*name == '\0') {
401 			/*
402 			 * Linux abstract namespace starts with a NULL byte.
403 			 * XXX We do not support abstract namespace yet.
404 			 */
405 			namelen = strnlen(name + 1, salen - hdrlen - 1) + 1;
406 		} else
407 			namelen = strnlen(name, salen - hdrlen);
408 		salen = hdrlen + namelen;
409 		if (salen > sizeof(struct sockaddr_un)) {
410 			error = ENAMETOOLONG;
411 			goto out;
412 		}
413 	}
414 
415 	if (bdom == AF_NETLINK) {
416 		if (salen < sizeof(struct sockaddr_nl)) {
417 			error = EINVAL;
418 			goto out;
419 		}
420 		salen = sizeof(struct sockaddr_nl);
421 	}
422 
423 	sa = (struct sockaddr *)kosa;
424 	sa->sa_family = bdom;
425 	sa->sa_len = salen;
426 
427 	if (sap != NULL) {
428 		*sap = sa;
429 		*len = salen;
430 	}
431 	return (0);
432 
433 out:
434 	if (sap != NULL)
435 		free(kosa, M_SONAME);
436 	return (error);
437 }
438 
439 void
linux_dev_shm_create(void)440 linux_dev_shm_create(void)
441 {
442 	int error;
443 
444 	error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &dev_shm_cdev,
445 	    &dev_shm_cdevsw, NULL, UID_ROOT, GID_WHEEL, 0, "shm/.mountpoint");
446 	if (error != 0) {
447 		printf("%s: failed to create device node, error %d\n",
448 		    __func__, error);
449 	}
450 }
451 
452 void
linux_dev_shm_destroy(void)453 linux_dev_shm_destroy(void)
454 {
455 
456 	destroy_dev(dev_shm_cdev);
457 }
458 
459 int
bsd_to_linux_bits_(int value,struct bsd_to_linux_bitmap * bitmap,size_t mapcnt,int no_value)460 bsd_to_linux_bits_(int value, struct bsd_to_linux_bitmap *bitmap,
461     size_t mapcnt, int no_value)
462 {
463 	int bsd_mask, bsd_value, linux_mask, linux_value;
464 	int linux_ret;
465 	size_t i;
466 	bool applied;
467 
468 	applied = false;
469 	linux_ret = 0;
470 	for (i = 0; i < mapcnt; ++i) {
471 		bsd_mask = bitmap[i].bsd_mask;
472 		bsd_value = bitmap[i].bsd_value;
473 		if (bsd_mask == 0)
474 			bsd_mask = bsd_value;
475 
476 		linux_mask = bitmap[i].linux_mask;
477 		linux_value = bitmap[i].linux_value;
478 		if (linux_mask == 0)
479 			linux_mask = linux_value;
480 
481 		/*
482 		 * If a mask larger than just the value is set, we explicitly
483 		 * want to make sure that only this bit we mapped within that
484 		 * mask is set.
485 		 */
486 		if ((value & bsd_mask) == bsd_value) {
487 			linux_ret = (linux_ret & ~linux_mask) | linux_value;
488 			applied = true;
489 		}
490 	}
491 
492 	if (!applied)
493 		return (no_value);
494 	return (linux_ret);
495 }
496 
497 int
linux_to_bsd_bits_(int value,struct bsd_to_linux_bitmap * bitmap,size_t mapcnt,int no_value)498 linux_to_bsd_bits_(int value, struct bsd_to_linux_bitmap *bitmap,
499     size_t mapcnt, int no_value)
500 {
501 	int bsd_mask, bsd_value, linux_mask, linux_value;
502 	int bsd_ret;
503 	size_t i;
504 	bool applied;
505 
506 	applied = false;
507 	bsd_ret = 0;
508 	for (i = 0; i < mapcnt; ++i) {
509 		bsd_mask = bitmap[i].bsd_mask;
510 		bsd_value = bitmap[i].bsd_value;
511 		if (bsd_mask == 0)
512 			bsd_mask = bsd_value;
513 
514 		linux_mask = bitmap[i].linux_mask;
515 		linux_value = bitmap[i].linux_value;
516 		if (linux_mask == 0)
517 			linux_mask = linux_value;
518 
519 		/*
520 		 * If a mask larger than just the value is set, we explicitly
521 		 * want to make sure that only this bit we mapped within that
522 		 * mask is set.
523 		 */
524 		if ((value & linux_mask) == linux_value) {
525 			bsd_ret = (bsd_ret & ~bsd_mask) | bsd_value;
526 			applied = true;
527 		}
528 	}
529 
530 	if (!applied)
531 		return (no_value);
532 	return (bsd_ret);
533 }
534 
535 void
linux_to_bsd_poll_events(struct thread * td,int fd,short lev,short * bev)536 linux_to_bsd_poll_events(struct thread *td, int fd, short lev,
537     short *bev)
538 {
539 	struct file *fp;
540 	int error;
541 	short bits = 0;
542 
543 	if (lev & LINUX_POLLIN)
544 		bits |= POLLIN;
545 	if (lev & LINUX_POLLPRI)
546 		bits |=	POLLPRI;
547 	if (lev & LINUX_POLLOUT)
548 		bits |= POLLOUT;
549 	if (lev & LINUX_POLLERR)
550 		bits |= POLLERR;
551 	if (lev & LINUX_POLLHUP)
552 		bits |= POLLHUP;
553 	if (lev & LINUX_POLLNVAL)
554 		bits |= POLLNVAL;
555 	if (lev & LINUX_POLLRDNORM)
556 		bits |= POLLRDNORM;
557 	if (lev & LINUX_POLLRDBAND)
558 		bits |= POLLRDBAND;
559 	if (lev & LINUX_POLLWRBAND)
560 		bits |= POLLWRBAND;
561 	if (lev & LINUX_POLLWRNORM)
562 		bits |= POLLWRNORM;
563 
564 	if (lev & LINUX_POLLRDHUP) {
565 		/*
566 		 * It seems that the Linux silencly ignores POLLRDHUP
567 		 * on non-socket file descriptors unlike FreeBSD, where
568 		 * events bits is more strictly checked (POLLSTANDARD).
569 		 */
570 		error = fget_unlocked(td, fd, &cap_no_rights, &fp);
571 		if (error == 0) {
572 			/*
573 			 * XXX. On FreeBSD POLLRDHUP applies only to
574 			 * stream sockets.
575 			 */
576 			if (fp->f_type == DTYPE_SOCKET)
577 				bits |= POLLRDHUP;
578 			fdrop(fp, td);
579 		}
580 	}
581 
582 	if (lev & LINUX_POLLMSG)
583 		LINUX_RATELIMIT_MSG_OPT1("unsupported POLLMSG, events(%d)", lev);
584 	if (lev & LINUX_POLLREMOVE)
585 		LINUX_RATELIMIT_MSG_OPT1("unsupported POLLREMOVE, events(%d)", lev);
586 
587 	*bev = bits;
588 }
589 
590 void
bsd_to_linux_poll_events(short bev,short * lev)591 bsd_to_linux_poll_events(short bev, short *lev)
592 {
593 	short bits = 0;
594 
595 	if (bev & POLLIN)
596 		bits |= LINUX_POLLIN;
597 	if (bev & POLLPRI)
598 		bits |=	LINUX_POLLPRI;
599 	if (bev & (POLLOUT | POLLWRNORM))
600 		/*
601 		 * POLLWRNORM is equal to POLLOUT on FreeBSD,
602 		 * but not on Linux
603 		 */
604 		bits |= LINUX_POLLOUT;
605 	if (bev & POLLERR)
606 		bits |= LINUX_POLLERR;
607 	if (bev & POLLHUP)
608 		bits |= LINUX_POLLHUP;
609 	if (bev & POLLNVAL)
610 		bits |= LINUX_POLLNVAL;
611 	if (bev & POLLRDNORM)
612 		bits |= LINUX_POLLRDNORM;
613 	if (bev & POLLRDBAND)
614 		bits |= LINUX_POLLRDBAND;
615 	if (bev & POLLWRBAND)
616 		bits |= LINUX_POLLWRBAND;
617 	if (bev & POLLRDHUP)
618 		bits |= LINUX_POLLRDHUP;
619 
620 	*lev = bits;
621 }
622