xref: /dragonfly/sys/kern/sys_generic.c (revision d21d24f1)
1 /*
2  * Copyright (c) 1982, 1986, 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
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  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)sys_generic.c	8.5 (Berkeley) 1/21/94
35  * $FreeBSD: src/sys/kern/sys_generic.c,v 1.55.2.10 2001/03/17 10:39:32 peter Exp $
36  */
37 
38 #include "opt_ktrace.h"
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/sysproto.h>
43 #include <sys/event.h>
44 #include <sys/filedesc.h>
45 #include <sys/filio.h>
46 #include <sys/fcntl.h>
47 #include <sys/file.h>
48 #include <sys/proc.h>
49 #include <sys/signalvar.h>
50 #include <sys/socketvar.h>
51 #include <sys/malloc.h>
52 #include <sys/uio.h>
53 #include <sys/kernel.h>
54 #include <sys/kern_syscall.h>
55 #include <sys/mapped_ioctl.h>
56 #include <sys/poll.h>
57 #include <sys/queue.h>
58 #include <sys/resourcevar.h>
59 #include <sys/socketops.h>
60 #include <sys/sysctl.h>
61 #include <sys/sysent.h>
62 #include <sys/buf.h>
63 #ifdef KTRACE
64 #include <sys/ktrace.h>
65 #endif
66 #include <vm/vm.h>
67 #include <vm/vm_page.h>
68 
69 #include <sys/file2.h>
70 #include <sys/spinlock2.h>
71 
72 #include <machine/limits.h>
73 
74 static MALLOC_DEFINE(M_IOCTLOPS, "ioctlops", "ioctl data buffer");
75 static MALLOC_DEFINE(M_IOCTLMAP, "ioctlmap", "mapped ioctl handler buffer");
76 static MALLOC_DEFINE(M_SELECT, "select", "select() buffer");
77 MALLOC_DEFINE(M_IOV, "iov", "large iov's");
78 
79 typedef struct kfd_set {
80         fd_mask	fds_bits[2];
81 } kfd_set;
82 
83 enum select_copyin_states {
84     COPYIN_READ, COPYIN_WRITE, COPYIN_EXCEPT, COPYIN_DONE };
85 
86 struct select_kevent_copyin_args {
87 	kfd_set		*read_set;
88 	kfd_set		*write_set;
89 	kfd_set		*except_set;
90 	int		active_set;	/* One of select_copyin_states */
91 	struct lwp	*lwp;		/* Pointer to our lwp */
92 	int		num_fds;	/* Number of file descriptors (syscall arg) */
93 	int		proc_fds;	/* Processed fd's (wraps) */
94 	int		error;		/* Returned to userland */
95 };
96 
97 struct poll_kevent_copyin_args {
98 	struct lwp	*lwp;
99 	struct pollfd	*fds;
100 	int		nfds;
101 	int		pfds;
102 	int		error;
103 };
104 
105 static struct lwkt_token mioctl_token = LWKT_TOKEN_INITIALIZER(mioctl_token);
106 
107 static int 	doselect(int nd, fd_set *in, fd_set *ou, fd_set *ex,
108 			 struct timespec *ts, int *res);
109 static int	dopoll(int nfds, struct pollfd *fds, struct timespec *ts,
110 		       int *res, int flags);
111 static int	dofileread(int, struct file *, struct uio *, int, size_t *);
112 static int	dofilewrite(int, struct file *, struct uio *, int, size_t *);
113 
114 /*
115  * Read system call.
116  *
117  * MPSAFE
118  */
119 int
120 sys_read(struct read_args *uap)
121 {
122 	struct thread *td = curthread;
123 	struct uio auio;
124 	struct iovec aiov;
125 	int error;
126 
127 	if ((ssize_t)uap->nbyte < 0)
128 		error = EINVAL;
129 
130 	aiov.iov_base = uap->buf;
131 	aiov.iov_len = uap->nbyte;
132 	auio.uio_iov = &aiov;
133 	auio.uio_iovcnt = 1;
134 	auio.uio_offset = -1;
135 	auio.uio_resid = uap->nbyte;
136 	auio.uio_rw = UIO_READ;
137 	auio.uio_segflg = UIO_USERSPACE;
138 	auio.uio_td = td;
139 
140 	error = kern_preadv(uap->fd, &auio, 0, &uap->sysmsg_szresult);
141 	return(error);
142 }
143 
144 /*
145  * Positioned (Pread) read system call
146  *
147  * MPSAFE
148  */
149 int
150 sys_extpread(struct extpread_args *uap)
151 {
152 	struct thread *td = curthread;
153 	struct uio auio;
154 	struct iovec aiov;
155 	int error;
156 	int flags;
157 
158 	if ((ssize_t)uap->nbyte < 0)
159 		return(EINVAL);
160 
161 	aiov.iov_base = uap->buf;
162 	aiov.iov_len = uap->nbyte;
163 	auio.uio_iov = &aiov;
164 	auio.uio_iovcnt = 1;
165 	auio.uio_offset = uap->offset;
166 	auio.uio_resid = uap->nbyte;
167 	auio.uio_rw = UIO_READ;
168 	auio.uio_segflg = UIO_USERSPACE;
169 	auio.uio_td = td;
170 
171 	flags = uap->flags & O_FMASK;
172 	if (uap->offset != (off_t)-1)
173 		flags |= O_FOFFSET;
174 
175 	error = kern_preadv(uap->fd, &auio, flags, &uap->sysmsg_szresult);
176 	return(error);
177 }
178 
179 /*
180  * Scatter read system call.
181  *
182  * MPSAFE
183  */
184 int
185 sys_readv(struct readv_args *uap)
186 {
187 	struct thread *td = curthread;
188 	struct uio auio;
189 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
190 	int error;
191 
192 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
193 			     &auio.uio_resid);
194 	if (error)
195 		return (error);
196 	auio.uio_iov = iov;
197 	auio.uio_iovcnt = uap->iovcnt;
198 	auio.uio_offset = -1;
199 	auio.uio_rw = UIO_READ;
200 	auio.uio_segflg = UIO_USERSPACE;
201 	auio.uio_td = td;
202 
203 	error = kern_preadv(uap->fd, &auio, 0, &uap->sysmsg_szresult);
204 
205 	iovec_free(&iov, aiov);
206 	return (error);
207 }
208 
209 
210 /*
211  * Scatter positioned read system call.
212  *
213  * MPSAFE
214  */
215 int
216 sys_extpreadv(struct extpreadv_args *uap)
217 {
218 	struct thread *td = curthread;
219 	struct uio auio;
220 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
221 	int error;
222 	int flags;
223 
224 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
225 			     &auio.uio_resid);
226 	if (error)
227 		return (error);
228 	auio.uio_iov = iov;
229 	auio.uio_iovcnt = uap->iovcnt;
230 	auio.uio_offset = uap->offset;
231 	auio.uio_rw = UIO_READ;
232 	auio.uio_segflg = UIO_USERSPACE;
233 	auio.uio_td = td;
234 
235 	flags = uap->flags & O_FMASK;
236 	if (uap->offset != (off_t)-1)
237 		flags |= O_FOFFSET;
238 
239 	error = kern_preadv(uap->fd, &auio, flags, &uap->sysmsg_szresult);
240 
241 	iovec_free(&iov, aiov);
242 	return(error);
243 }
244 
245 /*
246  * MPSAFE
247  */
248 int
249 kern_preadv(int fd, struct uio *auio, int flags, size_t *res)
250 {
251 	struct thread *td = curthread;
252 	struct file *fp;
253 	int error;
254 
255 	fp = holdfp(td, fd, FREAD);
256 	if (fp == NULL)
257 		return (EBADF);
258 	if (flags & O_FOFFSET && fp->f_type != DTYPE_VNODE) {
259 		error = ESPIPE;
260 	} else {
261 		error = dofileread(fd, fp, auio, flags, res);
262 	}
263 	dropfp(td, fd, fp);
264 
265 	return(error);
266 }
267 
268 /*
269  * Common code for readv and preadv that reads data in
270  * from a file using the passed in uio, offset, and flags.
271  *
272  * MPALMOSTSAFE - ktrace needs help
273  */
274 static int
275 dofileread(int fd, struct file *fp, struct uio *auio, int flags, size_t *res)
276 {
277 	int error;
278 	size_t len;
279 #ifdef KTRACE
280 	struct thread *td = curthread;
281 	struct iovec *ktriov = NULL;
282 	struct uio ktruio;
283 #endif
284 
285 #ifdef KTRACE
286 	/*
287 	 * if tracing, save a copy of iovec
288 	 */
289 	if (KTRPOINT(td, KTR_GENIO))  {
290 		int iovlen = auio->uio_iovcnt * sizeof(struct iovec);
291 
292 		ktriov = kmalloc(iovlen, M_TEMP, M_WAITOK);
293 		bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen);
294 		ktruio = *auio;
295 	}
296 #endif
297 	len = auio->uio_resid;
298 	error = fo_read(fp, auio, fp->f_cred, flags);
299 	if (error) {
300 		if (auio->uio_resid != len && (error == ERESTART ||
301 		    error == EINTR || error == EWOULDBLOCK))
302 			error = 0;
303 	}
304 #ifdef KTRACE
305 	if (ktriov != NULL) {
306 		if (error == 0) {
307 			ktruio.uio_iov = ktriov;
308 			ktruio.uio_resid = len - auio->uio_resid;
309 			ktrgenio(td->td_lwp, fd, UIO_READ, &ktruio, error);
310 		}
311 		kfree(ktriov, M_TEMP);
312 	}
313 #endif
314 	if (error == 0)
315 		*res = len - auio->uio_resid;
316 
317 	return(error);
318 }
319 
320 /*
321  * Write system call
322  *
323  * MPSAFE
324  */
325 int
326 sys_write(struct write_args *uap)
327 {
328 	struct thread *td = curthread;
329 	struct uio auio;
330 	struct iovec aiov;
331 	int error;
332 
333 	if ((ssize_t)uap->nbyte < 0)
334 		error = EINVAL;
335 
336 	aiov.iov_base = (void *)(uintptr_t)uap->buf;
337 	aiov.iov_len = uap->nbyte;
338 	auio.uio_iov = &aiov;
339 	auio.uio_iovcnt = 1;
340 	auio.uio_offset = -1;
341 	auio.uio_resid = uap->nbyte;
342 	auio.uio_rw = UIO_WRITE;
343 	auio.uio_segflg = UIO_USERSPACE;
344 	auio.uio_td = td;
345 
346 	error = kern_pwritev(uap->fd, &auio, 0, &uap->sysmsg_szresult);
347 
348 	return(error);
349 }
350 
351 /*
352  * Pwrite system call
353  *
354  * MPSAFE
355  */
356 int
357 sys_extpwrite(struct extpwrite_args *uap)
358 {
359 	struct thread *td = curthread;
360 	struct uio auio;
361 	struct iovec aiov;
362 	int error;
363 	int flags;
364 
365 	if ((ssize_t)uap->nbyte < 0)
366 		error = EINVAL;
367 
368 	aiov.iov_base = (void *)(uintptr_t)uap->buf;
369 	aiov.iov_len = uap->nbyte;
370 	auio.uio_iov = &aiov;
371 	auio.uio_iovcnt = 1;
372 	auio.uio_offset = uap->offset;
373 	auio.uio_resid = uap->nbyte;
374 	auio.uio_rw = UIO_WRITE;
375 	auio.uio_segflg = UIO_USERSPACE;
376 	auio.uio_td = td;
377 
378 	flags = uap->flags & O_FMASK;
379 	if (uap->offset != (off_t)-1)
380 		flags |= O_FOFFSET;
381 	error = kern_pwritev(uap->fd, &auio, flags, &uap->sysmsg_szresult);
382 	return(error);
383 }
384 
385 /*
386  * MPSAFE
387  */
388 int
389 sys_writev(struct writev_args *uap)
390 {
391 	struct thread *td = curthread;
392 	struct uio auio;
393 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
394 	int error;
395 
396 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
397 			     &auio.uio_resid);
398 	if (error)
399 		return (error);
400 	auio.uio_iov = iov;
401 	auio.uio_iovcnt = uap->iovcnt;
402 	auio.uio_offset = -1;
403 	auio.uio_rw = UIO_WRITE;
404 	auio.uio_segflg = UIO_USERSPACE;
405 	auio.uio_td = td;
406 
407 	error = kern_pwritev(uap->fd, &auio, 0, &uap->sysmsg_szresult);
408 
409 	iovec_free(&iov, aiov);
410 	return (error);
411 }
412 
413 
414 /*
415  * Gather positioned write system call
416  *
417  * MPSAFE
418  */
419 int
420 sys_extpwritev(struct extpwritev_args *uap)
421 {
422 	struct thread *td = curthread;
423 	struct uio auio;
424 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
425 	int error;
426 	int flags;
427 
428 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
429 			     &auio.uio_resid);
430 	if (error)
431 		return (error);
432 	auio.uio_iov = iov;
433 	auio.uio_iovcnt = uap->iovcnt;
434 	auio.uio_offset = uap->offset;
435 	auio.uio_rw = UIO_WRITE;
436 	auio.uio_segflg = UIO_USERSPACE;
437 	auio.uio_td = td;
438 
439 	flags = uap->flags & O_FMASK;
440 	if (uap->offset != (off_t)-1)
441 		flags |= O_FOFFSET;
442 
443 	error = kern_pwritev(uap->fd, &auio, flags, &uap->sysmsg_szresult);
444 
445 	iovec_free(&iov, aiov);
446 	return(error);
447 }
448 
449 /*
450  * MPSAFE
451  */
452 int
453 kern_pwritev(int fd, struct uio *auio, int flags, size_t *res)
454 {
455 	struct thread *td = curthread;
456 	struct file *fp;
457 	int error;
458 
459 	fp = holdfp(td, fd, FWRITE);
460 	if (fp == NULL)
461 		return (EBADF);
462 	else if ((flags & O_FOFFSET) && fp->f_type != DTYPE_VNODE) {
463 		error = ESPIPE;
464 	} else {
465 		error = dofilewrite(fd, fp, auio, flags, res);
466 	}
467 	dropfp(td, fd, fp);
468 
469 	return(error);
470 }
471 
472 /*
473  * Common code for writev and pwritev that writes data to
474  * a file using the passed in uio, offset, and flags.
475  *
476  * MPALMOSTSAFE - ktrace needs help
477  */
478 static int
479 dofilewrite(int fd, struct file *fp, struct uio *auio, int flags, size_t *res)
480 {
481 	struct thread *td = curthread;
482 	struct lwp *lp = td->td_lwp;
483 	int error;
484 	size_t len;
485 #ifdef KTRACE
486 	struct iovec *ktriov = NULL;
487 	struct uio ktruio;
488 #endif
489 
490 #ifdef KTRACE
491 	/*
492 	 * if tracing, save a copy of iovec and uio
493 	 */
494 	if (KTRPOINT(td, KTR_GENIO))  {
495 		int iovlen = auio->uio_iovcnt * sizeof(struct iovec);
496 
497 		ktriov = kmalloc(iovlen, M_TEMP, M_WAITOK);
498 		bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen);
499 		ktruio = *auio;
500 	}
501 #endif
502 	len = auio->uio_resid;
503 	error = fo_write(fp, auio, fp->f_cred, flags);
504 	if (error) {
505 		if (auio->uio_resid != len && (error == ERESTART ||
506 		    error == EINTR || error == EWOULDBLOCK))
507 			error = 0;
508 		/* Socket layer is responsible for issuing SIGPIPE. */
509 		if (error == EPIPE && fp->f_type != DTYPE_SOCKET)
510 			lwpsignal(lp->lwp_proc, lp, SIGPIPE);
511 	}
512 #ifdef KTRACE
513 	if (ktriov != NULL) {
514 		if (error == 0) {
515 			ktruio.uio_iov = ktriov;
516 			ktruio.uio_resid = len - auio->uio_resid;
517 			ktrgenio(lp, fd, UIO_WRITE, &ktruio, error);
518 		}
519 		kfree(ktriov, M_TEMP);
520 	}
521 #endif
522 	if (error == 0)
523 		*res = len - auio->uio_resid;
524 
525 	return(error);
526 }
527 
528 /*
529  * Ioctl system call
530  *
531  * MPSAFE
532  */
533 int
534 sys_ioctl(struct ioctl_args *uap)
535 {
536 	int error;
537 
538 	error = mapped_ioctl(uap->fd, uap->com, uap->data, NULL, &uap->sysmsg);
539 	return (error);
540 }
541 
542 struct ioctl_map_entry {
543 	const char *subsys;
544 	struct ioctl_map_range *cmd_ranges;
545 	LIST_ENTRY(ioctl_map_entry) entries;
546 };
547 
548 /*
549  * The true heart of all ioctl syscall handlers (native, emulation).
550  * If map != NULL, it will be searched for a matching entry for com,
551  * and appropriate conversions/conversion functions will be utilized.
552  *
553  * MPSAFE
554  */
555 int
556 mapped_ioctl(int fd, u_long com, caddr_t uspc_data, struct ioctl_map *map,
557 	     struct sysmsg *msg)
558 {
559 	struct thread *td = curthread;
560 	struct proc *p = td->td_proc;
561 	struct ucred *cred;
562 	struct file *fp;
563 	struct ioctl_map_range *iomc = NULL;
564 	int error;
565 	u_int size;
566 	u_long ocom = com;
567 	caddr_t data, memp;
568 	int tmp;
569 #define STK_PARAMS	128
570 	union {
571 	    char stkbuf[STK_PARAMS];
572 	    long align;
573 	} ubuf;
574 
575 	KKASSERT(p);
576 	cred = td->td_ucred;
577 	memp = NULL;
578 
579 	fp = holdfp(td, fd, FREAD|FWRITE);
580 	if (fp == NULL)
581 		return(EBADF);
582 
583 	if (map != NULL) {	/* obey translation map */
584 		u_long maskcmd;
585 		struct ioctl_map_entry *e;
586 
587 		maskcmd = com & map->mask;
588 
589 		lwkt_gettoken(&mioctl_token);
590 		LIST_FOREACH(e, &map->mapping, entries) {
591 			for (iomc = e->cmd_ranges; iomc->start != 0 ||
592 			     iomc->maptocmd != 0 || iomc->wrapfunc != NULL ||
593 			     iomc->mapfunc != NULL;
594 			     iomc++) {
595 				if (maskcmd >= iomc->start &&
596 				    maskcmd <= iomc->end)
597 					break;
598 			}
599 
600 			/* Did we find a match? */
601 			if (iomc->start != 0 || iomc->maptocmd != 0 ||
602 			    iomc->wrapfunc != NULL || iomc->mapfunc != NULL)
603 				break;
604 		}
605 		lwkt_reltoken(&mioctl_token);
606 
607 		if (iomc == NULL ||
608 		    (iomc->start == 0 && iomc->maptocmd == 0
609 		     && iomc->wrapfunc == NULL && iomc->mapfunc == NULL)) {
610 			kprintf("%s: 'ioctl' fd=%d, cmd=0x%lx ('%c',%d) not implemented\n",
611 			       map->sys, fd, maskcmd,
612 			       (int)((maskcmd >> 8) & 0xff),
613 			       (int)(maskcmd & 0xff));
614 			error = EINVAL;
615 			goto done;
616 		}
617 
618 		/*
619 		 * If it's a non-range one to one mapping, maptocmd should be
620 		 * correct. If it's a ranged one to one mapping, we pass the
621 		 * original value of com, and for a range mapped to a different
622 		 * range, we always need a mapping function to translate the
623 		 * ioctl to our native ioctl. Ex. 6500-65ff <-> 9500-95ff
624 		 */
625 		if (iomc->start == iomc->end && iomc->maptocmd == iomc->maptoend) {
626 			com = iomc->maptocmd;
627 		} else if (iomc->start == iomc->maptocmd && iomc->end == iomc->maptoend) {
628 			if (iomc->mapfunc != NULL)
629 				com = iomc->mapfunc(iomc->start, iomc->end,
630 						    iomc->start, iomc->end,
631 						    com, com);
632 		} else {
633 			if (iomc->mapfunc != NULL) {
634 				com = iomc->mapfunc(iomc->start, iomc->end,
635 						    iomc->maptocmd, iomc->maptoend,
636 						    com, ocom);
637 			} else {
638 				kprintf("%s: Invalid mapping for fd=%d, cmd=%#lx ('%c',%d)\n",
639 				       map->sys, fd, maskcmd,
640 				       (int)((maskcmd >> 8) & 0xff),
641 				       (int)(maskcmd & 0xff));
642 				error = EINVAL;
643 				goto done;
644 			}
645 		}
646 	}
647 
648 	switch (com) {
649 	case FIONCLEX:
650 		error = fclrfdflags(p->p_fd, fd, UF_EXCLOSE);
651 		goto done;
652 	case FIOCLEX:
653 		error = fsetfdflags(p->p_fd, fd, UF_EXCLOSE);
654 		goto done;
655 	}
656 
657 	/*
658 	 * Interpret high order word to find amount of data to be
659 	 * copied to/from the user's address space.
660 	 */
661 	size = IOCPARM_LEN(com);
662 	if (size > IOCPARM_MAX) {
663 		error = ENOTTY;
664 		goto done;
665 	}
666 
667 	if ((com & IOC_VOID) == 0 && size > sizeof(ubuf.stkbuf)) {
668 		memp = kmalloc(size, M_IOCTLOPS, M_WAITOK);
669 		data = memp;
670 	} else {
671 		memp = NULL;
672 		data = ubuf.stkbuf;
673 	}
674 	if (com & IOC_VOID) {
675 		*(caddr_t *)data = uspc_data;
676 	} else if (com & IOC_IN) {
677 		if (size != 0) {
678 			error = copyin(uspc_data, data, (size_t)size);
679 			if (error)
680 				goto done;
681 		} else {
682 			*(caddr_t *)data = uspc_data;
683 		}
684 	} else if ((com & IOC_OUT) != 0 && size) {
685 		/*
686 		 * Zero the buffer so the user always
687 		 * gets back something deterministic.
688 		 */
689 		bzero(data, (size_t)size);
690 	}
691 
692 	switch (com) {
693 	case FIONBIO:
694 		if ((tmp = *(int *)data))
695 			atomic_set_int(&fp->f_flag, FNONBLOCK);
696 		else
697 			atomic_clear_int(&fp->f_flag, FNONBLOCK);
698 		error = 0;
699 		break;
700 
701 	case FIOASYNC:
702 		if ((tmp = *(int *)data))
703 			atomic_set_int(&fp->f_flag, FASYNC);
704 		else
705 			atomic_clear_int(&fp->f_flag, FASYNC);
706 		error = fo_ioctl(fp, FIOASYNC, (caddr_t)&tmp, cred, msg);
707 		break;
708 
709 	default:
710 		/*
711 		 *  If there is a override function,
712 		 *  call it instead of directly routing the call
713 		 */
714 		if (map != NULL && iomc->wrapfunc != NULL)
715 			error = iomc->wrapfunc(fp, com, ocom, data, cred);
716 		else
717 			error = fo_ioctl(fp, com, data, cred, msg);
718 		/*
719 		 * Copy any data to user, size was
720 		 * already set and checked above.
721 		 */
722 		if (error == 0 && (com & IOC_OUT) != 0 && size != 0)
723 			error = copyout(data, uspc_data, (size_t)size);
724 		break;
725 	}
726 done:
727 	if (memp != NULL)
728 		kfree(memp, M_IOCTLOPS);
729 	dropfp(td, fd, fp);
730 
731 	return(error);
732 }
733 
734 /*
735  * MPSAFE
736  */
737 int
738 mapped_ioctl_register_handler(struct ioctl_map_handler *he)
739 {
740 	struct ioctl_map_entry *ne;
741 
742 	KKASSERT(he != NULL && he->map != NULL && he->cmd_ranges != NULL &&
743 		 he->subsys != NULL && *he->subsys != '\0');
744 
745 	ne = kmalloc(sizeof(struct ioctl_map_entry), M_IOCTLMAP,
746 		     M_WAITOK | M_ZERO);
747 
748 	ne->subsys = he->subsys;
749 	ne->cmd_ranges = he->cmd_ranges;
750 
751 	lwkt_gettoken(&mioctl_token);
752 	LIST_INSERT_HEAD(&he->map->mapping, ne, entries);
753 	lwkt_reltoken(&mioctl_token);
754 
755 	return(0);
756 }
757 
758 /*
759  * MPSAFE
760  */
761 int
762 mapped_ioctl_unregister_handler(struct ioctl_map_handler *he)
763 {
764 	struct ioctl_map_entry *ne;
765 	int error = EINVAL;
766 
767 	KKASSERT(he != NULL && he->map != NULL && he->cmd_ranges != NULL);
768 
769 	lwkt_gettoken(&mioctl_token);
770 	LIST_FOREACH(ne, &he->map->mapping, entries) {
771 		if (ne->cmd_ranges == he->cmd_ranges) {
772 			LIST_REMOVE(ne, entries);
773 			kfree(ne, M_IOCTLMAP);
774 			error = 0;
775 			break;
776 		}
777 	}
778 	lwkt_reltoken(&mioctl_token);
779 	return(error);
780 }
781 
782 static int	nselcoll;	/* Select collisions since boot */
783 int	selwait;
784 SYSCTL_INT(_kern, OID_AUTO, nselcoll, CTLFLAG_RD, &nselcoll, 0, "");
785 static int	nseldebug;
786 SYSCTL_INT(_kern, OID_AUTO, nseldebug, CTLFLAG_RW, &nseldebug, 0, "");
787 
788 /*
789  * Select system call.
790  *
791  * MPSAFE
792  */
793 int
794 sys_select(struct select_args *uap)
795 {
796 	struct timeval ktv;
797 	struct timespec *ktsp, kts;
798 	int error;
799 
800 	/*
801 	 * Get timeout if any.
802 	 */
803 	if (uap->tv != NULL) {
804 		error = copyin(uap->tv, &ktv, sizeof (ktv));
805 		if (error)
806 			return (error);
807 		TIMEVAL_TO_TIMESPEC(&ktv, &kts);
808 		ktsp = &kts;
809 	} else {
810 		ktsp = NULL;
811 	}
812 
813 	/*
814 	 * Do real work.
815 	 */
816 	error = doselect(uap->nd, uap->in, uap->ou, uap->ex, ktsp,
817 			 &uap->sysmsg_result);
818 
819 	return (error);
820 }
821 
822 
823 /*
824  * Pselect system call.
825  */
826 int
827 sys_pselect(struct pselect_args *uap)
828 {
829 	struct thread *td = curthread;
830 	struct lwp *lp = td->td_lwp;
831 	struct timespec *ktsp, kts;
832 	sigset_t sigmask;
833 	int error;
834 
835 	/*
836 	 * Get timeout if any.
837 	 */
838 	if (uap->ts != NULL) {
839 		error = copyin(uap->ts, &kts, sizeof (kts));
840 		if (error)
841 			return (error);
842 		ktsp = &kts;
843 	} else {
844 		ktsp = NULL;
845 	}
846 
847 	/*
848 	 * Install temporary signal mask if any provided.
849 	 */
850 	if (uap->sigmask != NULL) {
851 		error = copyin(uap->sigmask, &sigmask, sizeof(sigmask));
852 		if (error)
853 			return (error);
854 		lwkt_gettoken(&lp->lwp_proc->p_token);
855 		lp->lwp_oldsigmask = lp->lwp_sigmask;
856 		SIG_CANTMASK(sigmask);
857 		lp->lwp_sigmask = sigmask;
858 		lwkt_reltoken(&lp->lwp_proc->p_token);
859 	}
860 
861 	/*
862 	 * Do real job.
863 	 */
864 	error = doselect(uap->nd, uap->in, uap->ou, uap->ex, ktsp,
865 			 &uap->sysmsg_result);
866 
867 	if (uap->sigmask != NULL) {
868 		lwkt_gettoken(&lp->lwp_proc->p_token);
869 		/* doselect() responsible for turning ERESTART into EINTR */
870 		KKASSERT(error != ERESTART);
871 		if (error == EINTR) {
872 			/*
873 			 * We can't restore the previous signal mask now
874 			 * because it could block the signal that interrupted
875 			 * us.  So make a note to restore it after executing
876 			 * the handler.
877 			 */
878 			lp->lwp_flags |= LWP_OLDMASK;
879 		} else {
880 			/*
881 			 * No handler to run. Restore previous mask immediately.
882 			 */
883 			lp->lwp_sigmask = lp->lwp_oldsigmask;
884 		}
885 		lwkt_reltoken(&lp->lwp_proc->p_token);
886 	}
887 
888 	return (error);
889 }
890 
891 static int
892 select_copyin(void *arg, struct kevent *kevp, int maxevents, int *events)
893 {
894 	struct select_kevent_copyin_args *skap = NULL;
895 	struct kevent *kev;
896 	int fd;
897 	kfd_set *fdp = NULL;
898 	short filter = 0;
899 	u_int fflags = 0;
900 
901 	skap = (struct select_kevent_copyin_args *)arg;
902 
903 	if (*events == maxevents)
904 		return (0);
905 
906 	while (skap->active_set < COPYIN_DONE) {
907 		switch (skap->active_set) {
908 		case COPYIN_READ:
909 			/*
910 			 * Register descriptors for the read filter
911 			 */
912 			fdp = skap->read_set;
913 			filter = EVFILT_READ;
914 			fflags = NOTE_OLDAPI;
915 			if (fdp)
916 				break;
917 			++skap->active_set;
918 			skap->proc_fds = 0;
919 			/* fall through */
920 		case COPYIN_WRITE:
921 			/*
922 			 * Register descriptors for the write filter
923 			 */
924 			fdp = skap->write_set;
925 			filter = EVFILT_WRITE;
926 			fflags = NOTE_OLDAPI;
927 			if (fdp)
928 				break;
929 			++skap->active_set;
930 			skap->proc_fds = 0;
931 			/* fall through */
932 		case COPYIN_EXCEPT:
933 			/*
934 			 * Register descriptors for the exception filter
935 			 */
936 			fdp = skap->except_set;
937 			filter = EVFILT_EXCEPT;
938 			fflags = NOTE_OLDAPI | NOTE_OOB;
939 			if (fdp)
940 				break;
941 			++skap->active_set;
942 			skap->proc_fds = 0;
943 			/* fall through */
944 		case COPYIN_DONE:
945 			/*
946 			 * Nothing left to register
947 			 */
948 			return(0);
949 			/* NOT REACHED */
950 		}
951 
952 		while (skap->proc_fds < skap->num_fds) {
953 			fd = skap->proc_fds;
954 			if (FD_ISSET(fd, fdp)) {
955 				kev = &kevp[*events];
956 				EV_SET(kev, fd, filter,
957 				       EV_ADD|EV_ENABLE,
958 				       fflags, 0,
959 				       (void *)(uintptr_t)
960 					skap->lwp->lwp_kqueue_serial);
961 				FD_CLR(fd, fdp);
962 				++*events;
963 
964 				if (nseldebug) {
965 					kprintf("select fd %d filter %d "
966 					    "serial %ju\n", fd, filter,
967 					    (uintmax_t)
968 					    skap->lwp->lwp_kqueue_serial);
969 				}
970 			}
971 			++skap->proc_fds;
972 			if (*events == maxevents)
973 				return (0);
974 		}
975 		skap->active_set++;
976 		skap->proc_fds = 0;
977 	}
978 
979 	return (0);
980 }
981 
982 static int
983 select_copyout(void *arg, struct kevent *kevp, int count, int *res)
984 {
985 	struct select_kevent_copyin_args *skap;
986 	struct kevent kev;
987 	int i;
988 	int n;
989 
990 	skap = (struct select_kevent_copyin_args *)arg;
991 
992 	for (i = 0; i < count; ++i) {
993 		/*
994 		 * Filter out and delete spurious events
995 		 */
996 		if ((uint64_t)(uintptr_t)kevp[i].udata !=
997 		    skap->lwp->lwp_kqueue_serial) {
998 deregister:
999 			kev = kevp[i];
1000 			kev.flags = EV_DISABLE|EV_DELETE;
1001 			n = 1;
1002 			kqueue_register(&skap->lwp->lwp_kqueue, &kev, &n);
1003 			if (nseldebug) {
1004 				kprintf("select fd %ju mismatched serial %ju\n",
1005 				    (uintmax_t)kevp[i].ident,
1006 				    (uintmax_t)skap->lwp->lwp_kqueue_serial);
1007 			}
1008 			continue;
1009 		}
1010 
1011 		/*
1012 		 * Handle errors
1013 		 */
1014 		if (kevp[i].flags & EV_ERROR) {
1015 			int error = kevp[i].data;
1016 
1017 			switch (error) {
1018 			case EBADF:
1019 				/*
1020 				 * A bad file descriptor is considered a
1021 				 * fatal error for select, bail out.
1022 				 */
1023 				skap->error = error;
1024 				*res = -1;
1025 				return error;
1026 
1027 			default:
1028 				/*
1029 				 * Select silently swallows any unknown errors
1030 				 * for descriptors in the read or write sets.
1031 				 *
1032 				 * ALWAYS filter out EOPNOTSUPP errors from
1033 				 * filters (at least until all filters support
1034 				 * EVFILT_EXCEPT)
1035 				 *
1036 				 * We also filter out ENODEV since dev_dkqfilter
1037 				 * returns ENODEV if EOPNOTSUPP is returned in an
1038 				 * inner call.
1039 				 *
1040 				 * XXX: fix this
1041 				 */
1042 				if (kevp[i].filter != EVFILT_READ &&
1043 				    kevp[i].filter != EVFILT_WRITE &&
1044 				    error != EOPNOTSUPP &&
1045 				    error != ENODEV) {
1046 					skap->error = error;
1047 					*res = -1;
1048 					return error;
1049 				}
1050 				break;
1051 			}
1052 
1053 			/*
1054 			 * We must deregister any unsupported select events
1055 			 * to avoid a live-lock.
1056 			 */
1057 			if (nseldebug) {
1058 				kprintf("select fd %ju filter %d error %d\n",
1059 					(uintmax_t)kevp[i].ident,
1060 					kevp[i].filter, error);
1061 			}
1062 			goto deregister;
1063 		}
1064 
1065 		switch (kevp[i].filter) {
1066 		case EVFILT_READ:
1067 			FD_SET(kevp[i].ident, skap->read_set);
1068 			break;
1069 		case EVFILT_WRITE:
1070 			FD_SET(kevp[i].ident, skap->write_set);
1071 			break;
1072 		case EVFILT_EXCEPT:
1073 			FD_SET(kevp[i].ident, skap->except_set);
1074 			break;
1075 		}
1076 
1077 		++*res;
1078 	}
1079 
1080 	return (0);
1081 }
1082 
1083 /*
1084  * Copy select bits in from userland.  Allocate kernel memory if the
1085  * set is large.
1086  */
1087 static int
1088 getbits(int bytes, fd_set *in_set, kfd_set **out_set, kfd_set *tmp_set)
1089 {
1090 	int error;
1091 
1092 	if (in_set) {
1093 		if (bytes < sizeof(*tmp_set))
1094 			*out_set = tmp_set;
1095 		else
1096 			*out_set = kmalloc(bytes, M_SELECT, M_WAITOK);
1097 		error = copyin(in_set, *out_set, bytes);
1098 	} else {
1099 		*out_set = NULL;
1100 		error = 0;
1101 	}
1102 	return (error);
1103 }
1104 
1105 /*
1106  * Copy returned select bits back out to userland.
1107  */
1108 static int
1109 putbits(int bytes, kfd_set *in_set, fd_set *out_set)
1110 {
1111 	int error;
1112 
1113 	if (in_set) {
1114 		error = copyout(in_set, out_set, bytes);
1115 	} else {
1116 		error = 0;
1117 	}
1118 	return (error);
1119 }
1120 
1121 static int
1122 dotimeout_only(struct timespec *ts)
1123 {
1124 	return(nanosleep1(ts, NULL));
1125 }
1126 
1127 /*
1128  * Common code for sys_select() and sys_pselect().
1129  *
1130  * in, out and ex are userland pointers.  ts must point to validated
1131  * kernel-side timeout value or NULL for infinite timeout.  res must
1132  * point to syscall return value.
1133  */
1134 static int
1135 doselect(int nd, fd_set *read, fd_set *write, fd_set *except,
1136 	 struct timespec *ts, int *res)
1137 {
1138 	struct proc *p = curproc;
1139 	struct select_kevent_copyin_args *kap, ka;
1140 	int bytes, error;
1141 	kfd_set read_tmp;
1142 	kfd_set write_tmp;
1143 	kfd_set except_tmp;
1144 
1145 	*res = 0;
1146 	if (nd < 0)
1147 		return (EINVAL);
1148 	if (nd == 0 && ts)
1149 		return (dotimeout_only(ts));
1150 
1151 	if (nd > p->p_fd->fd_nfiles)		/* limit kmalloc */
1152 		nd = p->p_fd->fd_nfiles;
1153 
1154 	kap = &ka;
1155 	kap->lwp = curthread->td_lwp;
1156 	kap->num_fds = nd;
1157 	kap->proc_fds = 0;
1158 	kap->error = 0;
1159 	kap->active_set = COPYIN_READ;
1160 
1161 	/*
1162 	 * Calculate bytes based on the number of __fd_mask[] array entries
1163 	 * multiplied by the size of __fd_mask.
1164 	 */
1165 	bytes = howmany(nd, __NFDBITS) * sizeof(__fd_mask);
1166 
1167 	/* kap->read_set = NULL; not needed */
1168 	kap->write_set = NULL;
1169 	kap->except_set = NULL;
1170 
1171 	error = getbits(bytes, read, &kap->read_set, &read_tmp);
1172 	if (error == 0)
1173 		error = getbits(bytes, write, &kap->write_set, &write_tmp);
1174 	if (error == 0)
1175 		error = getbits(bytes, except, &kap->except_set, &except_tmp);
1176 	if (error)
1177 		goto done;
1178 
1179 	/*
1180 	 * NOTE: Make sure the max events passed to kern_kevent() is
1181 	 *	 effectively unlimited.  (nd * 3) accomplishes this.
1182 	 *
1183 	 *	 (*res) continues to increment as returned events are
1184 	 *	 loaded in.
1185 	 */
1186 	error = kern_kevent(&kap->lwp->lwp_kqueue, 0x7FFFFFFF, res, kap,
1187 			    select_copyin, select_copyout, ts, 0);
1188 	if (error == 0)
1189 		error = putbits(bytes, kap->read_set, read);
1190 	if (error == 0)
1191 		error = putbits(bytes, kap->write_set, write);
1192 	if (error == 0)
1193 		error = putbits(bytes, kap->except_set, except);
1194 
1195 	/*
1196 	 * An error from an individual event that should be passed
1197 	 * back to userland (EBADF)
1198 	 */
1199 	if (kap->error)
1200 		error = kap->error;
1201 
1202 	/*
1203 	 * Clean up.
1204 	 */
1205 done:
1206 	if (kap->read_set && kap->read_set != &read_tmp)
1207 		kfree(kap->read_set, M_SELECT);
1208 	if (kap->write_set && kap->write_set != &write_tmp)
1209 		kfree(kap->write_set, M_SELECT);
1210 	if (kap->except_set && kap->except_set != &except_tmp)
1211 		kfree(kap->except_set, M_SELECT);
1212 
1213 	kap->lwp->lwp_kqueue_serial += kap->num_fds;
1214 
1215 	return (error);
1216 }
1217 
1218 /*
1219  * Poll system call.
1220  *
1221  * MPSAFE
1222  */
1223 int
1224 sys_poll(struct poll_args *uap)
1225 {
1226 	struct timespec ts, *tsp;
1227 	int error;
1228 
1229 	if (uap->timeout != INFTIM) {
1230 		if (uap->timeout < 0)
1231 			return (EINVAL);
1232 		ts.tv_sec = uap->timeout / 1000;
1233 		ts.tv_nsec = (uap->timeout % 1000) * 1000 * 1000;
1234 		tsp = &ts;
1235 	} else {
1236 		tsp = NULL;
1237 	}
1238 
1239 	error = dopoll(uap->nfds, uap->fds, tsp, &uap->sysmsg_result, 0);
1240 
1241 	return (error);
1242 }
1243 
1244 /*
1245  * Ppoll system call.
1246  *
1247  * MPSAFE
1248  */
1249 int
1250 sys_ppoll(struct ppoll_args *uap)
1251 {
1252 	struct thread *td = curthread;
1253 	struct lwp *lp = td->td_lwp;
1254 	struct timespec *ktsp, kts;
1255 	sigset_t sigmask;
1256 	int error;
1257 
1258 	/*
1259 	 * Get timeout if any.
1260 	 */
1261 	if (uap->ts != NULL) {
1262 		error = copyin(uap->ts, &kts, sizeof (kts));
1263 		if (error)
1264 			return (error);
1265 		ktsp = &kts;
1266 	} else {
1267 		ktsp = NULL;
1268 	}
1269 
1270 	/*
1271 	 * Install temporary signal mask if any provided.
1272 	 */
1273 	if (uap->sigmask != NULL) {
1274 		error = copyin(uap->sigmask, &sigmask, sizeof(sigmask));
1275 		if (error)
1276 			return (error);
1277 		lwkt_gettoken(&lp->lwp_proc->p_token);
1278 		lp->lwp_oldsigmask = lp->lwp_sigmask;
1279 		SIG_CANTMASK(sigmask);
1280 		lp->lwp_sigmask = sigmask;
1281 		lwkt_reltoken(&lp->lwp_proc->p_token);
1282 	}
1283 
1284 	error = dopoll(uap->nfds, uap->fds, ktsp, &uap->sysmsg_result,
1285 	    ktsp != NULL ? KEVENT_TIMEOUT_PRECISE : 0);
1286 
1287 	if (uap->sigmask != NULL) {
1288 		lwkt_gettoken(&lp->lwp_proc->p_token);
1289 		/* dopoll() responsible for turning ERESTART into EINTR */
1290 		KKASSERT(error != ERESTART);
1291 		if (error == EINTR) {
1292 			/*
1293 			 * We can't restore the previous signal mask now
1294 			 * because it could block the signal that interrupted
1295 			 * us.  So make a note to restore it after executing
1296 			 * the handler.
1297 			 */
1298 			lp->lwp_flags |= LWP_OLDMASK;
1299 		} else {
1300 			/*
1301 			 * No handler to run. Restore previous mask immediately.
1302 			 */
1303 			lp->lwp_sigmask = lp->lwp_oldsigmask;
1304 		}
1305 		lwkt_reltoken(&lp->lwp_proc->p_token);
1306 	}
1307 
1308 	return (error);
1309 }
1310 
1311 static int
1312 poll_copyin(void *arg, struct kevent *kevp, int maxevents, int *events)
1313 {
1314 	struct poll_kevent_copyin_args *pkap;
1315 	struct pollfd *pfd;
1316 	struct kevent *kev;
1317 	int kev_count;
1318 
1319 	pkap = (struct poll_kevent_copyin_args *)arg;
1320 
1321 	while (pkap->pfds < pkap->nfds) {
1322 		pfd = &pkap->fds[pkap->pfds];
1323 
1324 		/* Clear return events */
1325 		pfd->revents = 0;
1326 
1327 		/* Do not check if fd is equal to -1 */
1328 		if (pfd->fd == -1) {
1329 			++pkap->pfds;
1330 			continue;
1331 		}
1332 
1333 		kev_count = 0;
1334 		if (pfd->events & (POLLIN | POLLRDNORM))
1335 			kev_count++;
1336 		if (pfd->events & (POLLOUT | POLLWRNORM))
1337 			kev_count++;
1338 		if (pfd->events & (POLLPRI | POLLRDBAND))
1339 			kev_count++;
1340 
1341 		if (*events + kev_count > maxevents)
1342 			return (0);
1343 
1344 		/*
1345 		 * NOTE: A combined serial number and poll array index is
1346 		 * stored in kev->udata.
1347 		 */
1348 		kev = &kevp[*events];
1349 		if (pfd->events & (POLLIN | POLLRDNORM)) {
1350 			EV_SET(kev++, pfd->fd, EVFILT_READ, EV_ADD|EV_ENABLE,
1351 			       NOTE_OLDAPI, 0, (void *)(uintptr_t)
1352 				(pkap->lwp->lwp_kqueue_serial + pkap->pfds));
1353 		}
1354 		if (pfd->events & (POLLOUT | POLLWRNORM)) {
1355 			EV_SET(kev++, pfd->fd, EVFILT_WRITE, EV_ADD|EV_ENABLE,
1356 			       NOTE_OLDAPI, 0, (void *)(uintptr_t)
1357 				(pkap->lwp->lwp_kqueue_serial + pkap->pfds));
1358 		}
1359 		if (pfd->events & (POLLPRI | POLLRDBAND)) {
1360 			EV_SET(kev++, pfd->fd, EVFILT_EXCEPT, EV_ADD|EV_ENABLE,
1361 			       NOTE_OLDAPI | NOTE_OOB, 0,
1362 			       (void *)(uintptr_t)
1363 				(pkap->lwp->lwp_kqueue_serial + pkap->pfds));
1364 		}
1365 
1366 		if (nseldebug) {
1367 			kprintf("poll index %d/%d fd %d events %08x "
1368 			    "serial %ju\n", pkap->pfds, pkap->nfds-1,
1369 			    pfd->fd, pfd->events,
1370 			    (uintmax_t)pkap->lwp->lwp_kqueue_serial);
1371 		}
1372 
1373 		++pkap->pfds;
1374 		(*events) += kev_count;
1375 	}
1376 
1377 	return (0);
1378 }
1379 
1380 static int
1381 poll_copyout(void *arg, struct kevent *kevp, int count, int *res)
1382 {
1383 	struct poll_kevent_copyin_args *pkap;
1384 	struct pollfd *pfd;
1385 	struct kevent kev;
1386 	int count_res;
1387 	int i;
1388 	int n;
1389 	uint64_t pi;
1390 
1391 	pkap = (struct poll_kevent_copyin_args *)arg;
1392 
1393 	for (i = 0; i < count; ++i) {
1394 		/*
1395 		 * Extract the poll array index and delete spurious events.
1396 		 * We can easily tell if the serial number is incorrect
1397 		 * by checking whether the extracted index is out of range.
1398 		 */
1399 		pi = (uint64_t)(uintptr_t)kevp[i].udata -
1400 		     pkap->lwp->lwp_kqueue_serial;
1401 
1402 		if (pi >= pkap->nfds) {
1403 deregister:
1404 			kev = kevp[i];
1405 			kev.flags = EV_DISABLE|EV_DELETE;
1406 			n = 1;
1407 			kqueue_register(&pkap->lwp->lwp_kqueue, &kev, &n);
1408 			if (nseldebug) {
1409 				kprintf("poll index %ju out of range against "
1410 				    "serial %ju\n", (uintmax_t)pi,
1411 				    (uintmax_t)pkap->lwp->lwp_kqueue_serial);
1412 			}
1413 			continue;
1414 		}
1415 
1416 		/*
1417 		 * Locate the pollfd and process events
1418 		 */
1419 		pfd = &pkap->fds[pi];
1420 		if (kevp[i].ident == pfd->fd) {
1421 			/*
1422 			 * A single descriptor may generate an error against
1423 			 * more than one filter, make sure to set the
1424 			 * appropriate flags but do not increment (*res)
1425 			 * more than once.
1426 			 */
1427 			count_res = (pfd->revents == 0);
1428 			if (kevp[i].flags & EV_ERROR) {
1429 				switch(kevp[i].data) {
1430 				case EBADF:
1431 				case POLLNVAL:
1432 					/* Bad file descriptor */
1433 					if (count_res)
1434 						++*res;
1435 					pfd->revents |= POLLNVAL;
1436 					break;
1437 				default:
1438 					/*
1439 					 * Poll silently swallows any unknown
1440 					 * errors except in the case of POLLPRI
1441 					 * (OOB/urgent data).
1442 					 *
1443 					 * ALWAYS filter out EOPNOTSUPP errors
1444 					 * from filters, common applications
1445 					 * set POLLPRI|POLLRDBAND and most
1446 					 * filters do not support EVFILT_EXCEPT.
1447 					 *
1448 					 * We also filter out ENODEV since
1449 					 * dev_dkqfilter returns ENODEV if
1450 					 * EOPNOTSUPP is returned in an
1451 					 * inner call.
1452 					 *
1453 					 * XXX: fix this
1454 					 */
1455 					if (kevp[i].filter != EVFILT_READ &&
1456 					    kevp[i].filter != EVFILT_WRITE &&
1457 					    kevp[i].data != EOPNOTSUPP &&
1458 					    kevp[i].data != ENODEV) {
1459 						if (count_res)
1460 							++*res;
1461 						pfd->revents |= POLLERR;
1462 					}
1463 					break;
1464 				}
1465 				if (pfd->revents == 0 && nseldebug) {
1466 					kprintf("poll index EV_ERROR %ju fd %d "
1467 						"filter %d error %jd\n",
1468 						(uintmax_t)pi, pfd->fd,
1469 						kevp[i].filter,
1470 						(intmax_t)kevp[i].data);
1471 				}
1472 
1473 				/*
1474 				 * Silently deregister any unhandled EV_ERROR
1475 				 * condition (usually EOPNOTSUPP).
1476 				 */
1477 				if (pfd->revents == 0)
1478 					goto deregister;
1479 				continue;
1480 			}
1481 
1482 			switch (kevp[i].filter) {
1483 			case EVFILT_READ:
1484 				/*
1485 				 * NODATA on the read side can indicate a
1486 				 * half-closed situation and not necessarily
1487 				 * a disconnect, so depend on the user
1488 				 * issuing a read() and getting 0 bytes back.
1489 				 *
1490 				 * If EV_HUP is set the peer completely
1491 				 * disconnected and we can set POLLHUP
1492 				 * once data is exhausted.
1493 				 */
1494 				if (kevp[i].flags & EV_NODATA) {
1495 					if (kevp[i].flags & EV_HUP)
1496 						pfd->revents |= POLLHUP;
1497 				}
1498 				if ((kevp[i].flags & EV_EOF) &&
1499 				    kevp[i].fflags != 0)
1500 					pfd->revents |= POLLERR;
1501 				if (pfd->events & POLLIN)
1502 					pfd->revents |= POLLIN;
1503 				if (pfd->events & POLLRDNORM)
1504 					pfd->revents |= POLLRDNORM;
1505 				break;
1506 			case EVFILT_WRITE:
1507 				/*
1508 				 * As per the OpenGroup POLLHUP is mutually
1509 				 * exclusive with the writability flags.  I
1510 				 * consider this a bit broken but...
1511 				 *
1512 				 * In this case a disconnect is implied even
1513 				 * for a half-closed (write side) situation.
1514 				 */
1515 				if (kevp[i].flags & EV_EOF) {
1516 					pfd->revents |= POLLHUP;
1517 					if (kevp[i].fflags != 0)
1518 						pfd->revents |= POLLERR;
1519 				} else {
1520 					if (pfd->events & POLLOUT)
1521 						pfd->revents |= POLLOUT;
1522 					if (pfd->events & POLLWRNORM)
1523 						pfd->revents |= POLLWRNORM;
1524 				}
1525 				break;
1526 			case EVFILT_EXCEPT:
1527 				/*
1528 				 * EV_NODATA should never be tagged for this
1529 				 * filter.
1530 				 */
1531 				if (pfd->events & POLLPRI)
1532 					pfd->revents |= POLLPRI;
1533 				if (pfd->events & POLLRDBAND)
1534 					pfd->revents |= POLLRDBAND;
1535 				break;
1536 			}
1537 
1538 			if (nseldebug) {
1539 				kprintf("poll index %ju/%d fd %d "
1540 				    "revents %08x\n", (uintmax_t)pi, pkap->nfds,
1541 				    pfd->fd, pfd->revents);
1542 			}
1543 
1544 			if (count_res && pfd->revents)
1545 				++*res;
1546 		}
1547 
1548 		/*
1549 		 * We must deregister any kqueue poll event that does not
1550 		 * set poll return bits to prevent a live-lock.
1551 		 */
1552 		if (pfd->revents == 0) {
1553 			kprintf("poll index %ju no-action %ju/%d "
1554 				"events=%08x kevpfilt=%d/%08x\n",
1555 			    (uintmax_t)pi, (uintmax_t)kevp[i].ident,
1556 			    pfd->fd, pfd->events,
1557 			    kevp[i].filter, kevp[i].flags);
1558 			goto deregister;
1559 		}
1560 	}
1561 
1562 	return (0);
1563 }
1564 
1565 static int
1566 dopoll(int nfds, struct pollfd *fds, struct timespec *ts, int *res, int flags)
1567 {
1568 	struct poll_kevent_copyin_args ka;
1569 	struct pollfd sfds[64];
1570 	int bytes;
1571 	int error;
1572 
1573         *res = 0;
1574         if (nfds < 0)
1575                 return (EINVAL);
1576 
1577 	if (nfds == 0 && ts)
1578 		return (dotimeout_only(ts));
1579 
1580 	/*
1581 	 * This is a bit arbitrary but we need to limit internal kmallocs.
1582 	 */
1583         if (nfds > maxfilesperproc * 2)
1584                 nfds = maxfilesperproc * 2;
1585 	bytes = sizeof(struct pollfd) * nfds;
1586 
1587 	ka.lwp = curthread->td_lwp;
1588 	ka.nfds = nfds;
1589 	ka.pfds = 0;
1590 	ka.error = 0;
1591 
1592 	if (ka.nfds < 64)
1593 		ka.fds = sfds;
1594 	else
1595 		ka.fds = kmalloc(bytes, M_SELECT, M_WAITOK);
1596 
1597 	error = copyin(fds, ka.fds, bytes);
1598 	if (error == 0)
1599 		error = kern_kevent(&ka.lwp->lwp_kqueue, 0x7FFFFFFF, res, &ka,
1600 				    poll_copyin, poll_copyout, ts, flags);
1601 
1602 	if (error == 0)
1603 		error = copyout(ka.fds, fds, bytes);
1604 
1605 	if (ka.fds != sfds)
1606 		kfree(ka.fds, M_SELECT);
1607 
1608 	ka.lwp->lwp_kqueue_serial += nfds;
1609 
1610 	return (error);
1611 }
1612 
1613 static int
1614 socket_wait_copyin(void *arg, struct kevent *kevp, int maxevents, int *events)
1615 {
1616 	return (0);
1617 }
1618 
1619 static int
1620 socket_wait_copyout(void *arg, struct kevent *kevp, int count, int *res)
1621 {
1622 	++*res;
1623 	return (0);
1624 }
1625 
1626 extern	struct fileops socketops;
1627 
1628 /*
1629  * NOTE: Callers of socket_wait() must already have a reference on the
1630  *	 socket.
1631  */
1632 int
1633 socket_wait(struct socket *so, struct timespec *ts, int *res)
1634 {
1635 	struct thread *td = curthread;
1636 	struct file *fp;
1637 	struct kqueue kq;
1638 	struct kevent kev;
1639 	int error, fd;
1640 	int n;
1641 
1642 	if ((error = falloc(td->td_lwp, &fp, &fd)) != 0)
1643 		return (error);
1644 
1645 	fp->f_type = DTYPE_SOCKET;
1646 	fp->f_flag = FREAD | FWRITE;
1647 	fp->f_ops = &socketops;
1648 	fp->f_data = so;
1649 	fsetfd(td->td_lwp->lwp_proc->p_fd, fp, fd);
1650 	fsetfdflags(td->td_proc->p_fd, fd, UF_EXCLOSE);
1651 
1652 	bzero(&kq, sizeof(kq));
1653 	kqueue_init(&kq, td->td_lwp->lwp_proc->p_fd);
1654 	EV_SET(&kev, fd, EVFILT_READ, EV_ADD|EV_ENABLE, 0, 0, NULL);
1655 	n = 1;
1656 	if ((error = kqueue_register(&kq, &kev, &n)) != 0) {
1657 		fdrop(fp);
1658 		return (error);
1659 	}
1660 
1661 	error = kern_kevent(&kq, 1, res, NULL, socket_wait_copyin,
1662 			    socket_wait_copyout, ts, 0);
1663 
1664 	EV_SET(&kev, fd, EVFILT_READ, EV_DELETE|EV_DISABLE, 0, 0, NULL);
1665 	n = 1;
1666 	kqueue_register(&kq, &kev, &n);
1667 	fp->f_ops = &badfileops;
1668 	fdrop(fp);
1669 
1670 	return (error);
1671 }
1672 
1673 /*
1674  * OpenBSD poll system call.
1675  * XXX this isn't quite a true representation..  OpenBSD uses select ops.
1676  *
1677  * MPSAFE
1678  */
1679 int
1680 sys_openbsd_poll(struct openbsd_poll_args *uap)
1681 {
1682 	return (sys_poll((struct poll_args *)uap));
1683 }
1684 
1685 /*ARGSUSED*/
1686 int
1687 seltrue(cdev_t dev, int events)
1688 {
1689 	return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
1690 }
1691