xref: /dflybsd-src/sys/kern/sys_generic.c (revision 3546e044efc2789e203cdc14abe0226e163e03d4)
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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)sys_generic.c	8.5 (Berkeley) 1/21/94
39  * $FreeBSD: src/sys/kern/sys_generic.c,v 1.55.2.10 2001/03/17 10:39:32 peter Exp $
40  * $DragonFly: src/sys/kern/sys_generic.c,v 1.49 2008/05/05 22:09:44 dillon Exp $
41  */
42 
43 #include "opt_ktrace.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/sysproto.h>
48 #include <sys/event.h>
49 #include <sys/filedesc.h>
50 #include <sys/filio.h>
51 #include <sys/fcntl.h>
52 #include <sys/file.h>
53 #include <sys/proc.h>
54 #include <sys/signalvar.h>
55 #include <sys/socketvar.h>
56 #include <sys/uio.h>
57 #include <sys/kernel.h>
58 #include <sys/kern_syscall.h>
59 #include <sys/malloc.h>
60 #include <sys/mapped_ioctl.h>
61 #include <sys/poll.h>
62 #include <sys/queue.h>
63 #include <sys/resourcevar.h>
64 #include <sys/sysctl.h>
65 #include <sys/sysent.h>
66 #include <sys/buf.h>
67 #ifdef KTRACE
68 #include <sys/ktrace.h>
69 #endif
70 #include <vm/vm.h>
71 #include <vm/vm_page.h>
72 
73 #include <sys/file2.h>
74 #include <sys/mplock2.h>
75 
76 #include <machine/limits.h>
77 
78 static MALLOC_DEFINE(M_IOCTLOPS, "ioctlops", "ioctl data buffer");
79 static MALLOC_DEFINE(M_IOCTLMAP, "ioctlmap", "mapped ioctl handler buffer");
80 static MALLOC_DEFINE(M_SELECT, "select", "select() buffer");
81 MALLOC_DEFINE(M_IOV, "iov", "large iov's");
82 
83 typedef struct kfd_set {
84         fd_mask	fds_bits[2];
85 } kfd_set;
86 
87 enum select_copyin_states {
88     COPYIN_READ, COPYIN_WRITE, COPYIN_EXCEPT, COPYIN_DONE };
89 
90 struct select_kevent_copyin_args {
91 	kfd_set		*read_set;
92 	kfd_set		*write_set;
93 	kfd_set		*except_set;
94 	int		active_set;	/* One of select_copyin_states */
95 	struct lwp	*lwp;		/* Pointer to our lwp */
96 	int		num_fds;	/* Number of file descriptors (syscall arg) */
97 	int		proc_fds;	/* Processed fd's (wraps) */
98 	int		error;		/* Returned to userland */
99 };
100 
101 struct poll_kevent_copyin_args {
102 	struct lwp	*lwp;
103 	struct pollfd	*fds;
104 	int		nfds;
105 	int		pfds;
106 	int		error;
107 };
108 
109 static int 	doselect(int nd, fd_set *in, fd_set *ou, fd_set *ex,
110 			 struct timespec *ts, int *res);
111 static int	dopoll(int nfds, struct pollfd *fds, struct timespec *ts,
112 		       int *res);
113 static int	dofileread(int, struct file *, struct uio *, int, size_t *);
114 static int	dofilewrite(int, struct file *, struct uio *, int, size_t *);
115 
116 /*
117  * Read system call.
118  *
119  * MPSAFE
120  */
121 int
122 sys_read(struct read_args *uap)
123 {
124 	struct thread *td = curthread;
125 	struct uio auio;
126 	struct iovec aiov;
127 	int error;
128 
129 	if ((ssize_t)uap->nbyte < 0)
130 		error = EINVAL;
131 
132 	aiov.iov_base = uap->buf;
133 	aiov.iov_len = uap->nbyte;
134 	auio.uio_iov = &aiov;
135 	auio.uio_iovcnt = 1;
136 	auio.uio_offset = -1;
137 	auio.uio_resid = uap->nbyte;
138 	auio.uio_rw = UIO_READ;
139 	auio.uio_segflg = UIO_USERSPACE;
140 	auio.uio_td = td;
141 
142 	error = kern_preadv(uap->fd, &auio, 0, &uap->sysmsg_szresult);
143 	return(error);
144 }
145 
146 /*
147  * Positioned (Pread) read system call
148  *
149  * MPSAFE
150  */
151 int
152 sys_extpread(struct extpread_args *uap)
153 {
154 	struct thread *td = curthread;
155 	struct uio auio;
156 	struct iovec aiov;
157 	int error;
158 	int flags;
159 
160 	if ((ssize_t)uap->nbyte < 0)
161 		return(EINVAL);
162 
163 	aiov.iov_base = uap->buf;
164 	aiov.iov_len = uap->nbyte;
165 	auio.uio_iov = &aiov;
166 	auio.uio_iovcnt = 1;
167 	auio.uio_offset = uap->offset;
168 	auio.uio_resid = uap->nbyte;
169 	auio.uio_rw = UIO_READ;
170 	auio.uio_segflg = UIO_USERSPACE;
171 	auio.uio_td = td;
172 
173 	flags = uap->flags & O_FMASK;
174 	if (uap->offset != (off_t)-1)
175 		flags |= O_FOFFSET;
176 
177 	error = kern_preadv(uap->fd, &auio, flags, &uap->sysmsg_szresult);
178 	return(error);
179 }
180 
181 /*
182  * Scatter read system call.
183  *
184  * MPSAFE
185  */
186 int
187 sys_readv(struct readv_args *uap)
188 {
189 	struct thread *td = curthread;
190 	struct uio auio;
191 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
192 	int error;
193 
194 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
195 			     &auio.uio_resid);
196 	if (error)
197 		return (error);
198 	auio.uio_iov = iov;
199 	auio.uio_iovcnt = uap->iovcnt;
200 	auio.uio_offset = -1;
201 	auio.uio_rw = UIO_READ;
202 	auio.uio_segflg = UIO_USERSPACE;
203 	auio.uio_td = td;
204 
205 	error = kern_preadv(uap->fd, &auio, 0, &uap->sysmsg_szresult);
206 
207 	iovec_free(&iov, aiov);
208 	return (error);
209 }
210 
211 
212 /*
213  * Scatter positioned read system call.
214  *
215  * MPSAFE
216  */
217 int
218 sys_extpreadv(struct extpreadv_args *uap)
219 {
220 	struct thread *td = curthread;
221 	struct uio auio;
222 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
223 	int error;
224 	int flags;
225 
226 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
227 			     &auio.uio_resid);
228 	if (error)
229 		return (error);
230 	auio.uio_iov = iov;
231 	auio.uio_iovcnt = uap->iovcnt;
232 	auio.uio_offset = uap->offset;
233 	auio.uio_rw = UIO_READ;
234 	auio.uio_segflg = UIO_USERSPACE;
235 	auio.uio_td = td;
236 
237 	flags = uap->flags & O_FMASK;
238 	if (uap->offset != (off_t)-1)
239 		flags |= O_FOFFSET;
240 
241 	error = kern_preadv(uap->fd, &auio, flags, &uap->sysmsg_szresult);
242 
243 	iovec_free(&iov, aiov);
244 	return(error);
245 }
246 
247 /*
248  * MPSAFE
249  */
250 int
251 kern_preadv(int fd, struct uio *auio, int flags, size_t *res)
252 {
253 	struct thread *td = curthread;
254 	struct proc *p = td->td_proc;
255 	struct file *fp;
256 	int error;
257 
258 	KKASSERT(p);
259 
260 	fp = holdfp(p->p_fd, fd, FREAD);
261 	if (fp == NULL)
262 		return (EBADF);
263 	if (flags & O_FOFFSET && fp->f_type != DTYPE_VNODE) {
264 		error = ESPIPE;
265 	} else {
266 		error = dofileread(fd, fp, auio, flags, res);
267 	}
268 	fdrop(fp);
269 	return(error);
270 }
271 
272 /*
273  * Common code for readv and preadv that reads data in
274  * from a file using the passed in uio, offset, and flags.
275  *
276  * MPALMOSTSAFE - ktrace needs help
277  */
278 static int
279 dofileread(int fd, struct file *fp, struct uio *auio, int flags, size_t *res)
280 {
281 	int error;
282 	size_t len;
283 #ifdef KTRACE
284 	struct thread *td = curthread;
285 	struct iovec *ktriov = NULL;
286 	struct uio ktruio;
287 #endif
288 
289 #ifdef KTRACE
290 	/*
291 	 * if tracing, save a copy of iovec
292 	 */
293 	if (KTRPOINT(td, KTR_GENIO))  {
294 		int iovlen = auio->uio_iovcnt * sizeof(struct iovec);
295 
296 		MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
297 		bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen);
298 		ktruio = *auio;
299 	}
300 #endif
301 	len = auio->uio_resid;
302 	error = fo_read(fp, auio, fp->f_cred, flags);
303 	if (error) {
304 		if (auio->uio_resid != len && (error == ERESTART ||
305 		    error == EINTR || error == EWOULDBLOCK))
306 			error = 0;
307 	}
308 #ifdef KTRACE
309 	if (ktriov != NULL) {
310 		if (error == 0) {
311 			ktruio.uio_iov = ktriov;
312 			ktruio.uio_resid = len - auio->uio_resid;
313 			get_mplock();
314 			ktrgenio(td->td_lwp, fd, UIO_READ, &ktruio, error);
315 			rel_mplock();
316 		}
317 		FREE(ktriov, M_TEMP);
318 	}
319 #endif
320 	if (error == 0)
321 		*res = len - auio->uio_resid;
322 
323 	return(error);
324 }
325 
326 /*
327  * Write system call
328  *
329  * MPSAFE
330  */
331 int
332 sys_write(struct write_args *uap)
333 {
334 	struct thread *td = curthread;
335 	struct uio auio;
336 	struct iovec aiov;
337 	int error;
338 
339 	if ((ssize_t)uap->nbyte < 0)
340 		error = EINVAL;
341 
342 	aiov.iov_base = (void *)(uintptr_t)uap->buf;
343 	aiov.iov_len = uap->nbyte;
344 	auio.uio_iov = &aiov;
345 	auio.uio_iovcnt = 1;
346 	auio.uio_offset = -1;
347 	auio.uio_resid = uap->nbyte;
348 	auio.uio_rw = UIO_WRITE;
349 	auio.uio_segflg = UIO_USERSPACE;
350 	auio.uio_td = td;
351 
352 	error = kern_pwritev(uap->fd, &auio, 0, &uap->sysmsg_szresult);
353 
354 	return(error);
355 }
356 
357 /*
358  * Pwrite system call
359  *
360  * MPSAFE
361  */
362 int
363 sys_extpwrite(struct extpwrite_args *uap)
364 {
365 	struct thread *td = curthread;
366 	struct uio auio;
367 	struct iovec aiov;
368 	int error;
369 	int flags;
370 
371 	if ((ssize_t)uap->nbyte < 0)
372 		error = EINVAL;
373 
374 	aiov.iov_base = (void *)(uintptr_t)uap->buf;
375 	aiov.iov_len = uap->nbyte;
376 	auio.uio_iov = &aiov;
377 	auio.uio_iovcnt = 1;
378 	auio.uio_offset = uap->offset;
379 	auio.uio_resid = uap->nbyte;
380 	auio.uio_rw = UIO_WRITE;
381 	auio.uio_segflg = UIO_USERSPACE;
382 	auio.uio_td = td;
383 
384 	flags = uap->flags & O_FMASK;
385 	if (uap->offset != (off_t)-1)
386 		flags |= O_FOFFSET;
387 	error = kern_pwritev(uap->fd, &auio, flags, &uap->sysmsg_szresult);
388 	return(error);
389 }
390 
391 /*
392  * MPSAFE
393  */
394 int
395 sys_writev(struct writev_args *uap)
396 {
397 	struct thread *td = curthread;
398 	struct uio auio;
399 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
400 	int error;
401 
402 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
403 			     &auio.uio_resid);
404 	if (error)
405 		return (error);
406 	auio.uio_iov = iov;
407 	auio.uio_iovcnt = uap->iovcnt;
408 	auio.uio_offset = -1;
409 	auio.uio_rw = UIO_WRITE;
410 	auio.uio_segflg = UIO_USERSPACE;
411 	auio.uio_td = td;
412 
413 	error = kern_pwritev(uap->fd, &auio, 0, &uap->sysmsg_szresult);
414 
415 	iovec_free(&iov, aiov);
416 	return (error);
417 }
418 
419 
420 /*
421  * Gather positioned write system call
422  *
423  * MPSAFE
424  */
425 int
426 sys_extpwritev(struct extpwritev_args *uap)
427 {
428 	struct thread *td = curthread;
429 	struct uio auio;
430 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
431 	int error;
432 	int flags;
433 
434 	error = iovec_copyin(uap->iovp, &iov, aiov, uap->iovcnt,
435 			     &auio.uio_resid);
436 	if (error)
437 		return (error);
438 	auio.uio_iov = iov;
439 	auio.uio_iovcnt = uap->iovcnt;
440 	auio.uio_offset = uap->offset;
441 	auio.uio_rw = UIO_WRITE;
442 	auio.uio_segflg = UIO_USERSPACE;
443 	auio.uio_td = td;
444 
445 	flags = uap->flags & O_FMASK;
446 	if (uap->offset != (off_t)-1)
447 		flags |= O_FOFFSET;
448 
449 	error = kern_pwritev(uap->fd, &auio, flags, &uap->sysmsg_szresult);
450 
451 	iovec_free(&iov, aiov);
452 	return(error);
453 }
454 
455 /*
456  * MPSAFE
457  */
458 int
459 kern_pwritev(int fd, struct uio *auio, int flags, size_t *res)
460 {
461 	struct thread *td = curthread;
462 	struct proc *p = td->td_proc;
463 	struct file *fp;
464 	int error;
465 
466 	KKASSERT(p);
467 
468 	fp = holdfp(p->p_fd, fd, FWRITE);
469 	if (fp == NULL)
470 		return (EBADF);
471 	else if ((flags & O_FOFFSET) && fp->f_type != DTYPE_VNODE) {
472 		error = ESPIPE;
473 	} else {
474 		error = dofilewrite(fd, fp, auio, flags, res);
475 	}
476 
477 	fdrop(fp);
478 	return (error);
479 }
480 
481 /*
482  * Common code for writev and pwritev that writes data to
483  * a file using the passed in uio, offset, and flags.
484  *
485  * MPALMOSTSAFE - ktrace needs help
486  */
487 static int
488 dofilewrite(int fd, struct file *fp, struct uio *auio, int flags, size_t *res)
489 {
490 	struct thread *td = curthread;
491 	struct lwp *lp = td->td_lwp;
492 	int error;
493 	size_t len;
494 #ifdef KTRACE
495 	struct iovec *ktriov = NULL;
496 	struct uio ktruio;
497 #endif
498 
499 #ifdef KTRACE
500 	/*
501 	 * if tracing, save a copy of iovec and uio
502 	 */
503 	if (KTRPOINT(td, KTR_GENIO))  {
504 		int iovlen = auio->uio_iovcnt * sizeof(struct iovec);
505 
506 		MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
507 		bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen);
508 		ktruio = *auio;
509 	}
510 #endif
511 	len = auio->uio_resid;
512 	error = fo_write(fp, auio, fp->f_cred, flags);
513 	if (error) {
514 		if (auio->uio_resid != len && (error == ERESTART ||
515 		    error == EINTR || error == EWOULDBLOCK))
516 			error = 0;
517 		/* Socket layer is responsible for issuing SIGPIPE. */
518 		if (error == EPIPE) {
519 			get_mplock();
520 			lwpsignal(lp->lwp_proc, lp, SIGPIPE);
521 			rel_mplock();
522 		}
523 	}
524 #ifdef KTRACE
525 	if (ktriov != NULL) {
526 		if (error == 0) {
527 			ktruio.uio_iov = ktriov;
528 			ktruio.uio_resid = len - auio->uio_resid;
529 			get_mplock();
530 			ktrgenio(lp, fd, UIO_WRITE, &ktruio, error);
531 			rel_mplock();
532 		}
533 		FREE(ktriov, M_TEMP);
534 	}
535 #endif
536 	if (error == 0)
537 		*res = len - auio->uio_resid;
538 
539 	return(error);
540 }
541 
542 /*
543  * Ioctl system call
544  *
545  * MPALMOSTSAFE
546  */
547 int
548 sys_ioctl(struct ioctl_args *uap)
549 {
550 	int error;
551 
552 	get_mplock();
553 	error = mapped_ioctl(uap->fd, uap->com, uap->data, NULL, &uap->sysmsg);
554 	rel_mplock();
555 	return (error);
556 }
557 
558 struct ioctl_map_entry {
559 	const char *subsys;
560 	struct ioctl_map_range *cmd_ranges;
561 	LIST_ENTRY(ioctl_map_entry) entries;
562 };
563 
564 /*
565  * The true heart of all ioctl syscall handlers (native, emulation).
566  * If map != NULL, it will be searched for a matching entry for com,
567  * and appropriate conversions/conversion functions will be utilized.
568  */
569 int
570 mapped_ioctl(int fd, u_long com, caddr_t uspc_data, struct ioctl_map *map,
571 	     struct sysmsg *msg)
572 {
573 	struct thread *td = curthread;
574 	struct proc *p = td->td_proc;
575 	struct ucred *cred;
576 	struct file *fp;
577 	struct ioctl_map_range *iomc = NULL;
578 	int error;
579 	u_int size;
580 	u_long ocom = com;
581 	caddr_t data, memp;
582 	int tmp;
583 #define STK_PARAMS	128
584 	union {
585 	    char stkbuf[STK_PARAMS];
586 	    long align;
587 	} ubuf;
588 
589 	KKASSERT(p);
590 	cred = td->td_ucred;
591 
592 	fp = holdfp(p->p_fd, fd, FREAD|FWRITE);
593 	if (fp == NULL)
594 		return(EBADF);
595 
596 	if (map != NULL) {	/* obey translation map */
597 		u_long maskcmd;
598 		struct ioctl_map_entry *e;
599 
600 		maskcmd = com & map->mask;
601 
602 		LIST_FOREACH(e, &map->mapping, entries) {
603 			for (iomc = e->cmd_ranges; iomc->start != 0 ||
604 			     iomc->maptocmd != 0 || iomc->wrapfunc != NULL ||
605 			     iomc->mapfunc != NULL;
606 			     iomc++) {
607 				if (maskcmd >= iomc->start &&
608 				    maskcmd <= iomc->end)
609 					break;
610 			}
611 
612 			/* Did we find a match? */
613 			if (iomc->start != 0 || iomc->maptocmd != 0 ||
614 			    iomc->wrapfunc != NULL || iomc->mapfunc != NULL)
615 				break;
616 		}
617 
618 		if (iomc == NULL ||
619 		    (iomc->start == 0 && iomc->maptocmd == 0
620 		     && iomc->wrapfunc == NULL && iomc->mapfunc == NULL)) {
621 			kprintf("%s: 'ioctl' fd=%d, cmd=0x%lx ('%c',%d) not implemented\n",
622 			       map->sys, fd, maskcmd,
623 			       (int)((maskcmd >> 8) & 0xff),
624 			       (int)(maskcmd & 0xff));
625 			error = EINVAL;
626 			goto done;
627 		}
628 
629 		/*
630 		 * If it's a non-range one to one mapping, maptocmd should be
631 		 * correct. If it's a ranged one to one mapping, we pass the
632 		 * original value of com, and for a range mapped to a different
633 		 * range, we always need a mapping function to translate the
634 		 * ioctl to our native ioctl. Ex. 6500-65ff <-> 9500-95ff
635 		 */
636 		if (iomc->start == iomc->end && iomc->maptocmd == iomc->maptoend) {
637 			com = iomc->maptocmd;
638 		} else if (iomc->start == iomc->maptocmd && iomc->end == iomc->maptoend) {
639 			if (iomc->mapfunc != NULL)
640 				com = iomc->mapfunc(iomc->start, iomc->end,
641 						    iomc->start, iomc->end,
642 						    com, com);
643 		} else {
644 			if (iomc->mapfunc != NULL) {
645 				com = iomc->mapfunc(iomc->start, iomc->end,
646 						    iomc->maptocmd, iomc->maptoend,
647 						    com, ocom);
648 			} else {
649 				kprintf("%s: Invalid mapping for fd=%d, cmd=%#lx ('%c',%d)\n",
650 				       map->sys, fd, maskcmd,
651 				       (int)((maskcmd >> 8) & 0xff),
652 				       (int)(maskcmd & 0xff));
653 				error = EINVAL;
654 				goto done;
655 			}
656 		}
657 	}
658 
659 	switch (com) {
660 	case FIONCLEX:
661 		error = fclrfdflags(p->p_fd, fd, UF_EXCLOSE);
662 		goto done;
663 	case FIOCLEX:
664 		error = fsetfdflags(p->p_fd, fd, UF_EXCLOSE);
665 		goto done;
666 	}
667 
668 	/*
669 	 * Interpret high order word to find amount of data to be
670 	 * copied to/from the user's address space.
671 	 */
672 	size = IOCPARM_LEN(com);
673 	if (size > IOCPARM_MAX) {
674 		error = ENOTTY;
675 		goto done;
676 	}
677 
678 	memp = NULL;
679 	if (size > sizeof (ubuf.stkbuf)) {
680 		memp = kmalloc(size, M_IOCTLOPS, M_WAITOK);
681 		data = memp;
682 	} else {
683 		data = ubuf.stkbuf;
684 	}
685 	if ((com & IOC_IN) != 0) {
686 		if (size != 0) {
687 			error = copyin(uspc_data, data, (size_t)size);
688 			if (error) {
689 				if (memp != NULL)
690 					kfree(memp, M_IOCTLOPS);
691 				goto done;
692 			}
693 		} else {
694 			*(caddr_t *)data = uspc_data;
695 		}
696 	} else if ((com & IOC_OUT) != 0 && size) {
697 		/*
698 		 * Zero the buffer so the user always
699 		 * gets back something deterministic.
700 		 */
701 		bzero(data, (size_t)size);
702 	} else if ((com & IOC_VOID) != 0) {
703 		*(caddr_t *)data = uspc_data;
704 	}
705 
706 	switch (com) {
707 	case FIONBIO:
708 		if ((tmp = *(int *)data))
709 			fp->f_flag |= FNONBLOCK;
710 		else
711 			fp->f_flag &= ~FNONBLOCK;
712 		error = 0;
713 		break;
714 
715 	case FIOASYNC:
716 		if ((tmp = *(int *)data))
717 			fp->f_flag |= FASYNC;
718 		else
719 			fp->f_flag &= ~FASYNC;
720 		error = fo_ioctl(fp, FIOASYNC, (caddr_t)&tmp, cred, msg);
721 		break;
722 
723 	default:
724 		/*
725 		 *  If there is a override function,
726 		 *  call it instead of directly routing the call
727 		 */
728 		if (map != NULL && iomc->wrapfunc != NULL)
729 			error = iomc->wrapfunc(fp, com, ocom, data, cred);
730 		else
731 			error = fo_ioctl(fp, com, data, cred, msg);
732 		/*
733 		 * Copy any data to user, size was
734 		 * already set and checked above.
735 		 */
736 		if (error == 0 && (com & IOC_OUT) != 0 && size != 0)
737 			error = copyout(data, uspc_data, (size_t)size);
738 		break;
739 	}
740 	if (memp != NULL)
741 		kfree(memp, M_IOCTLOPS);
742 done:
743 	fdrop(fp);
744 	return(error);
745 }
746 
747 int
748 mapped_ioctl_register_handler(struct ioctl_map_handler *he)
749 {
750 	struct ioctl_map_entry *ne;
751 
752 	KKASSERT(he != NULL && he->map != NULL && he->cmd_ranges != NULL &&
753 		 he->subsys != NULL && *he->subsys != '\0');
754 
755 	ne = kmalloc(sizeof(struct ioctl_map_entry), M_IOCTLMAP, M_WAITOK);
756 
757 	ne->subsys = he->subsys;
758 	ne->cmd_ranges = he->cmd_ranges;
759 
760 	LIST_INSERT_HEAD(&he->map->mapping, ne, entries);
761 
762 	return(0);
763 }
764 
765 int
766 mapped_ioctl_unregister_handler(struct ioctl_map_handler *he)
767 {
768 	struct ioctl_map_entry *ne;
769 
770 	KKASSERT(he != NULL && he->map != NULL && he->cmd_ranges != NULL);
771 
772 	LIST_FOREACH(ne, &he->map->mapping, entries) {
773 		if (ne->cmd_ranges != he->cmd_ranges)
774 			continue;
775 		LIST_REMOVE(ne, entries);
776 		kfree(ne, M_IOCTLMAP);
777 		return(0);
778 	}
779 	return(EINVAL);
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 
786 /*
787  * Select system call.
788  *
789  * MPSAFE
790  */
791 int
792 sys_select(struct select_args *uap)
793 {
794 	struct timeval ktv;
795 	struct timespec *ktsp, kts;
796 	int error;
797 
798 	/*
799 	 * Get timeout if any.
800 	 */
801 	if (uap->tv != NULL) {
802 		error = copyin(uap->tv, &ktv, sizeof (ktv));
803 		if (error)
804 			return (error);
805 		TIMEVAL_TO_TIMESPEC(&ktv, &kts);
806 		ktsp = &kts;
807 	} else {
808 		ktsp = NULL;
809 	}
810 
811 	/*
812 	 * Do real work.
813 	 */
814 	error = doselect(uap->nd, uap->in, uap->ou, uap->ex, ktsp,
815 			 &uap->sysmsg_result);
816 
817 	return (error);
818 }
819 
820 
821 /*
822  * Pselect system call.
823  *
824  * MPALMOSTSAFE
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 		get_mplock();
855 		lp->lwp_oldsigmask = lp->lwp_sigmask;
856 		SIG_CANTMASK(sigmask);
857 		lp->lwp_sigmask = sigmask;
858 	} else {
859 		get_mplock();
860 	}
861 
862 	/*
863 	 * Do real job.
864 	 */
865 	error = doselect(uap->nd, uap->in, uap->ou, uap->ex, ktsp,
866 			 &uap->sysmsg_result);
867 
868 	if (uap->sigmask != NULL) {
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_flag |= LWP_OLDMASK;
879 		} else {
880 			/*
881 			 * No handler to run. Restore previous mask immediately.
882 			 */
883 			lp->lwp_sigmask = lp->lwp_oldsigmask;
884 		}
885 	}
886 	rel_mplock();
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 = 0;
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 = 0;
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_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 *)skap->lwp->lwp_kqueue_serial);
960 				FD_CLR(fd, fdp);
961 				++*events;
962 			}
963 			++skap->proc_fds;
964 			if (*events == maxevents)
965 				return (0);
966 		}
967 		skap->active_set++;
968 		skap->proc_fds = 0;
969 	}
970 
971 	return (0);
972 }
973 
974 static int
975 select_copyout(void *arg, struct kevent *kevp, int count, int *res)
976 {
977 	struct select_kevent_copyin_args *skap;
978 	struct kevent kev;
979 	int i = 0;
980 
981 	skap = (struct select_kevent_copyin_args *)arg;
982 
983 	if (kevp[0].flags & EV_ERROR) {
984 		skap->error = kevp[0].data;
985 		return (0);
986 	}
987 
988 	for (i = 0; i < count; ++i) {
989 		if ((u_int)kevp[i].udata != skap->lwp->lwp_kqueue_serial) {
990 			kev = kevp[i];
991 			kev.flags = EV_DISABLE|EV_DELETE;
992 			kqueue_register(&skap->lwp->lwp_kqueue, &kev);
993 			continue;
994 		}
995 
996 		switch (kevp[i].filter) {
997 		case EVFILT_READ:
998 			FD_SET(kevp[i].ident, skap->read_set);
999 			break;
1000 		case EVFILT_WRITE:
1001 			FD_SET(kevp[i].ident, skap->write_set);
1002 			break;
1003 		case EVFILT_EXCEPT:
1004 			FD_SET(kevp[i].ident, skap->except_set);
1005 			break;
1006 		}
1007 
1008 		++*res;
1009 	}
1010 
1011 	return (0);
1012 }
1013 
1014 /*
1015  * Copy select bits in from userland.  Allocate kernel memory if the
1016  * set is large.
1017  */
1018 static int
1019 getbits(int bytes, fd_set *in_set, kfd_set **out_set, kfd_set *tmp_set)
1020 {
1021 	int error;
1022 
1023 	if (in_set) {
1024 		if (bytes < sizeof(*tmp_set))
1025 			*out_set = tmp_set;
1026 		else
1027 			*out_set = kmalloc(bytes, M_SELECT, M_WAITOK);
1028 		error = copyin(in_set, *out_set, bytes);
1029 	} else {
1030 		*out_set = NULL;
1031 		error = 0;
1032 	}
1033 	return (error);
1034 }
1035 
1036 /*
1037  * Copy returned select bits back out to userland.
1038  */
1039 static int
1040 putbits(int bytes, kfd_set *in_set, fd_set *out_set)
1041 {
1042 	int error;
1043 
1044 	if (in_set) {
1045 		error = copyout(in_set, out_set, bytes);
1046 	} else {
1047 		error = 0;
1048 	}
1049 	return (error);
1050 }
1051 
1052 /*
1053  * Common code for sys_select() and sys_pselect().
1054  *
1055  * in, out and ex are userland pointers.  ts must point to validated
1056  * kernel-side timeout value or NULL for infinite timeout.  res must
1057  * point to syscall return value.
1058  */
1059 static int
1060 doselect(int nd, fd_set *read, fd_set *write, fd_set *except,
1061 	 struct timespec *ts, int *res)
1062 {
1063 	struct proc *p = curproc;
1064 	struct select_kevent_copyin_args *kap, ka;
1065 	int bytes, error;
1066 	kfd_set read_tmp;
1067 	kfd_set write_tmp;
1068 	kfd_set except_tmp;
1069 
1070 	*res = 0;
1071 	if (nd < 0)
1072 		return (EINVAL);
1073 	if (nd > p->p_fd->fd_nfiles)		/* limit kmalloc */
1074 		nd = p->p_fd->fd_nfiles;
1075 
1076 	kap = &ka;
1077 	kap->lwp = curthread->td_lwp;
1078 	kap->num_fds = nd;
1079 	kap->proc_fds = 0;
1080 	kap->error = 0;
1081 	kap->active_set = COPYIN_READ;
1082 
1083 	/*
1084 	 * Calculate bytes based on the number of __fd_mask[] array entries
1085 	 * multiplied by the size of __fd_mask.
1086 	 */
1087 	bytes = howmany(nd, __NFDBITS) * sizeof(__fd_mask);
1088 
1089 	error = getbits(bytes, read, &kap->read_set, &read_tmp);
1090 	if (error == 0)
1091 		error = getbits(bytes, write, &kap->write_set, &write_tmp);
1092 	if (error == 0)
1093 		error = getbits(bytes, except, &kap->except_set, &except_tmp);
1094 	if (error)
1095 		goto done;
1096 
1097 	/*
1098 	 * NOTE: Make sure the max events passed to kern_kevent() is
1099 	 *	 effectively unlimited.  (nd * 3) accomplishes this.
1100 	 *
1101 	 *	 (*res) continues to increment as returned events are
1102 	 *	 loaded in.
1103 	 */
1104 	error = kern_kevent(&kap->lwp->lwp_kqueue, 0x7FFFFFFF, res, kap,
1105 			    select_copyin, select_copyout, ts);
1106 	if (error == 0)
1107 		error = putbits(bytes, kap->read_set, read);
1108 	if (error == 0)
1109 		error = putbits(bytes, kap->write_set, write);
1110 	if (error == 0)
1111 		error = putbits(bytes, kap->except_set, except);
1112 
1113 	/*
1114 	 * Cumulative error from individual events (EBADFD?)
1115 	 */
1116 	if (kap->error)
1117 		error = kap->error;
1118 
1119 	/*
1120 	 * Clean up.
1121 	 */
1122 done:
1123 	if (kap->read_set && kap->read_set != &read_tmp)
1124 		kfree(kap->read_set, M_SELECT);
1125 	if (kap->write_set && kap->write_set != &write_tmp)
1126 		kfree(kap->write_set, M_SELECT);
1127 	if (kap->except_set && kap->except_set != &except_tmp)
1128 		kfree(kap->except_set, M_SELECT);
1129 
1130 	kap->lwp->lwp_kqueue_serial++;
1131 
1132 	return (error);
1133 }
1134 
1135 /*
1136  * Poll system call.
1137  *
1138  * MPSAFE
1139  */
1140 int
1141 sys_poll(struct poll_args *uap)
1142 {
1143 	struct timespec ts, *tsp;
1144 	int error;
1145 
1146 	if (uap->timeout != INFTIM) {
1147 		ts.tv_sec = uap->timeout / 1000;
1148 		ts.tv_nsec = (uap->timeout % 1000) * 1000 * 1000;
1149 		tsp = &ts;
1150 	} else {
1151 		tsp = NULL;
1152 	}
1153 
1154 	error = dopoll(uap->nfds, uap->fds, tsp, &uap->sysmsg_result);
1155 
1156 	return (error);
1157 }
1158 
1159 static int
1160 poll_copyin(void *arg, struct kevent *kevp, int maxevents, int *events)
1161 {
1162 	struct poll_kevent_copyin_args *pkap;
1163 	struct pollfd *pfd;
1164 	struct kevent *kev;
1165 	int kev_count;
1166 
1167 	pkap = (struct poll_kevent_copyin_args *)arg;
1168 
1169 	while (pkap->pfds < pkap->nfds) {
1170 		pfd = &pkap->fds[pkap->pfds];
1171 
1172 		/* Clear return events */
1173 		pfd->revents = 0;
1174 
1175 		/* Do not check if fd is equal to -1 */
1176 		if (pfd->fd == -1) {
1177 			++pkap->pfds;
1178 			continue;
1179 		}
1180 
1181 		kev_count = 0;
1182 		if (pfd->events & (POLLIN | POLLRDNORM))
1183 			kev_count++;
1184 		if (pfd->events & (POLLOUT | POLLWRNORM))
1185 			kev_count++;
1186 		if (pfd->events & (POLLPRI | POLLRDBAND))
1187 			kev_count++;
1188 
1189 		if (*events + kev_count > maxevents)
1190 			return (0);
1191 
1192 		kev = &kevp[*events];
1193 		if (pfd->events & (POLLIN | POLLRDNORM))
1194 			EV_SET(kev++, pfd->fd, EVFILT_READ, EV_ADD|EV_ENABLE,
1195 			       0, 0, (void *)pkap->pfds);
1196 		if (pfd->events & (POLLOUT | POLLWRNORM))
1197 			EV_SET(kev++, pfd->fd, EVFILT_WRITE, EV_ADD|EV_ENABLE,
1198 			       0, 0, (void *)pkap->pfds);
1199 		if (pfd->events & (POLLPRI | POLLRDBAND))
1200 			EV_SET(kev++, pfd->fd, EVFILT_EXCEPT, EV_ADD|EV_ENABLE,
1201 			       NOTE_OOB, 0, (void *)pkap->pfds);
1202 
1203 		++pkap->pfds;
1204 		(*events) += kev_count;
1205 	}
1206 
1207 	return (0);
1208 }
1209 
1210 static int
1211 poll_copyout(void *arg, struct kevent *kevp, int count, int *res)
1212 {
1213 	struct poll_kevent_copyin_args *pkap;
1214 	struct pollfd *pfd;
1215 	struct kevent kev;
1216 	int i;
1217 
1218 	pkap = (struct poll_kevent_copyin_args *)arg;
1219 
1220 	for (i = 0; i < count; ++i) {
1221 		if ((int)kevp[i].udata < pkap->nfds) {
1222 			pfd = &pkap->fds[(int)kevp[i].udata];
1223 			if (kevp[i].ident == pfd->fd) {
1224 				if (kevp[i].flags & EV_ERROR) {
1225 					/* Bad file descriptor */
1226 					if (kevp[i].data == EBADF)
1227 						pfd->revents |= POLLNVAL;
1228 					else
1229 						pfd->revents |= POLLERR;
1230 
1231 					++*res;
1232 					continue;
1233 				}
1234 
1235 				if (kevp[i].flags & EV_EOF) {
1236 					pfd->revents |= POLLHUP;
1237 					++*res;
1238 					continue;
1239 				}
1240 
1241 				switch (kevp[i].filter) {
1242 				case EVFILT_READ:
1243 					pfd->revents |= (POLLIN | POLLRDNORM);
1244 					break;
1245 				case EVFILT_WRITE:
1246 					pfd->revents |= (POLLOUT | POLLWRNORM);
1247 					break;
1248 				case EVFILT_EXCEPT:
1249 					pfd->revents |= (POLLPRI | POLLRDBAND);
1250 					break;
1251 				}
1252 
1253 				++*res;
1254 				continue;
1255 			}
1256 		}
1257 
1258 		/* Remove descriptor not in pollfd set from kq */
1259 		kev = kevp[i];
1260 		kev.flags = EV_DISABLE|EV_DELETE;
1261 		kqueue_register(&pkap->lwp->lwp_kqueue, &kev);
1262 	}
1263 
1264 	return (0);
1265 }
1266 
1267 static int
1268 dopoll(int nfds, struct pollfd *fds, struct timespec *ts, int *res)
1269 {
1270 	struct poll_kevent_copyin_args ka;
1271 	struct pollfd sfds[64];
1272 	int bytes;
1273 	int error;
1274 
1275         *res = 0;
1276         if (nfds < 0)
1277                 return (EINVAL);
1278 
1279 	/*
1280 	 * This is a bit arbitrary but we need to limit internal kmallocs.
1281 	 */
1282         if (nfds > maxfilesperproc * 2)
1283                 nfds = maxfilesperproc * 2;
1284 	bytes = sizeof(struct pollfd) * nfds;
1285 
1286 	ka.lwp = curthread->td_lwp;
1287 	ka.nfds = nfds;
1288 	ka.pfds = 0;
1289 	ka.error = 0;
1290 
1291 	if (ka.nfds < 64)
1292 		ka.fds = sfds;
1293 	else
1294 		ka.fds = kmalloc(bytes, M_SELECT, M_WAITOK);
1295 
1296 	error = copyin(fds, ka.fds, bytes);
1297 	if (error == 0)
1298 		error = kern_kevent(&ka.lwp->lwp_kqueue, ka.nfds, res, &ka,
1299 				    poll_copyin, poll_copyout, ts);
1300 
1301 	if (error == 0)
1302 		error = copyout(ka.fds, fds, bytes);
1303 
1304 	if (ka.fds != sfds)
1305 		kfree(ka.fds, M_SELECT);
1306 
1307 	return (error);
1308 }
1309 
1310 /*
1311  * OpenBSD poll system call.
1312  * XXX this isn't quite a true representation..  OpenBSD uses select ops.
1313  *
1314  * MPSAFE
1315  */
1316 int
1317 sys_openbsd_poll(struct openbsd_poll_args *uap)
1318 {
1319 	return (sys_poll((struct poll_args *)uap));
1320 }
1321 
1322 /*ARGSUSED*/
1323 int
1324 seltrue(cdev_t dev, int events)
1325 {
1326 	return (events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
1327 }
1328 
1329 /*
1330  * Record a select request.  A global wait must be used since a process/thread
1331  * might go away after recording its request.
1332  */
1333 void
1334 selrecord(struct thread *selector, struct selinfo *sip)
1335 {
1336 	struct proc *p;
1337 	struct lwp *lp = NULL;
1338 
1339 	if (selector->td_lwp == NULL)
1340 		panic("selrecord: thread needs a process");
1341 
1342 	if (sip->si_pid == selector->td_proc->p_pid &&
1343 	    sip->si_tid == selector->td_lwp->lwp_tid)
1344 		return;
1345 	if (sip->si_pid && (p = pfind(sip->si_pid)))
1346 		lp = lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, sip->si_tid);
1347 	if (lp != NULL && lp->lwp_wchan == (caddr_t)&selwait) {
1348 		sip->si_flags |= SI_COLL;
1349 	} else {
1350 		sip->si_pid = selector->td_proc->p_pid;
1351 		sip->si_tid = selector->td_lwp->lwp_tid;
1352 	}
1353 }
1354 
1355 /*
1356  * Do a wakeup when a selectable event occurs.
1357  */
1358 void
1359 selwakeup(struct selinfo *sip)
1360 {
1361 	struct proc *p;
1362 	struct lwp *lp = NULL;
1363 
1364 	if (sip->si_pid == 0)
1365 		return;
1366 	if (sip->si_flags & SI_COLL) {
1367 		nselcoll++;
1368 		sip->si_flags &= ~SI_COLL;
1369 		wakeup((caddr_t)&selwait);	/* YYY fixable */
1370 	}
1371 	p = pfind(sip->si_pid);
1372 	sip->si_pid = 0;
1373 	if (p == NULL)
1374 		return;
1375 	lp = lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, sip->si_tid);
1376 	if (lp == NULL)
1377 		return;
1378 
1379 	/*
1380 	 * This is a temporary hack until the code can be rewritten.
1381 	 * Check LWP_SELECT before assuming we can setrunnable().
1382 	 * Otherwise we might catch the lwp before it actually goes to
1383 	 * sleep.
1384 	 */
1385 	crit_enter();
1386 	if (lp->lwp_flag & LWP_SELECT) {
1387 		lp->lwp_flag &= ~LWP_SELECT;
1388 	} else if (lp->lwp_wchan == (caddr_t)&selwait) {
1389 		/*
1390 		 * Flag the process to break the tsleep when
1391 		 * setrunnable is called, but only call setrunnable
1392 		 * here if the process is not in a stopped state.
1393 		 */
1394 		lp->lwp_flag |= LWP_BREAKTSLEEP;
1395 		if (p->p_stat != SSTOP)
1396 			setrunnable(lp);
1397 	}
1398 	crit_exit();
1399 
1400 	kqueue_wakeup(&lp->lwp_kqueue);
1401 }
1402 
1403