xref: /netbsd-src/sys/compat/linux/common/linux_misc.c (revision f5d3fbbc6ff4a77159fb268d247bd94cb7d7e332)
1 /*	$NetBSD: linux_misc.c,v 1.35 1997/10/10 22:16:10 fvdl Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 Frank van der Linden
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed for the NetBSD Project
18  *      by Frank van der Linden
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Linux compatibility module. Try to deal with various Linux system calls.
36  */
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/namei.h>
41 #include <sys/proc.h>
42 #include <sys/dirent.h>
43 #include <sys/file.h>
44 #include <sys/stat.h>
45 #include <sys/filedesc.h>
46 #include <sys/ioctl.h>
47 #include <sys/kernel.h>
48 #include <sys/malloc.h>
49 #include <sys/mbuf.h>
50 #include <sys/mman.h>
51 #include <sys/mount.h>
52 #include <sys/ptrace.h>
53 #include <sys/resource.h>
54 #include <sys/resourcevar.h>
55 #include <sys/signal.h>
56 #include <sys/signalvar.h>
57 #include <sys/socket.h>
58 #include <sys/time.h>
59 #include <sys/times.h>
60 #include <sys/vnode.h>
61 #include <sys/uio.h>
62 #include <sys/wait.h>
63 #include <sys/utsname.h>
64 #include <sys/unistd.h>
65 
66 #include <sys/syscallargs.h>
67 
68 #include <vm/vm.h>
69 #include <vm/vm_param.h>
70 
71 #include <compat/linux/linux_types.h>
72 #include <compat/linux/linux_fcntl.h>
73 #include <compat/linux/linux_mmap.h>
74 #include <compat/linux/linux_signal.h>
75 #include <compat/linux/linux_syscallargs.h>
76 #include <compat/linux/linux_util.h>
77 #include <compat/linux/linux_dirent.h>
78 
79 /* linux_misc.c */
80 static void bsd_to_linux_wstat __P((int *));
81 static void bsd_to_linux_statfs __P((struct statfs *, struct linux_statfs *));
82 int linux_select1 __P((struct proc *, register_t *, int, fd_set *, fd_set *,
83 		       fd_set *, struct timeval *));
84 
85 /*
86  * The information on a terminated (or stopped) process needs
87  * to be converted in order for Linux binaries to get a valid signal
88  * number out of it.
89  */
90 static void
91 bsd_to_linux_wstat(status)
92 	int *status;
93 {
94 
95 	if (WIFSIGNALED(*status))
96 		*status = (*status & ~0177) |
97 		    bsd_to_linux_sig[WTERMSIG(*status)];
98 	else if (WIFSTOPPED(*status))
99 		*status = (*status & ~0xff00) |
100 		    (bsd_to_linux_sig[WSTOPSIG(*status)] << 8);
101 }
102 
103 /*
104  * waitpid(2). Passed on to the NetBSD call, surrounded by code to
105  * reserve some space for a NetBSD-style wait status, and converting
106  * it to what Linux wants.
107  */
108 int
109 linux_sys_waitpid(p, v, retval)
110 	struct proc *p;
111 	void *v;
112 	register_t *retval;
113 {
114 	struct linux_sys_waitpid_args /* {
115 		syscallarg(int) pid;
116 		syscallarg(int *) status;
117 		syscallarg(int) options;
118 	} */ *uap = v;
119 	struct sys_wait4_args w4a;
120 	int error, *status, tstat;
121 	caddr_t sg;
122 
123 	if (SCARG(uap, status) != NULL) {
124 		sg = stackgap_init(p->p_emul);
125 		status = (int *) stackgap_alloc(&sg, sizeof status);
126 	} else
127 		status = NULL;
128 
129 	SCARG(&w4a, pid) = SCARG(uap, pid);
130 	SCARG(&w4a, status) = status;
131 	SCARG(&w4a, options) = SCARG(uap, options);
132 	SCARG(&w4a, rusage) = NULL;
133 
134 	if ((error = sys_wait4(p, &w4a, retval)))
135 		return error;
136 
137 	p->p_siglist &= ~sigmask(SIGCHLD);
138 
139 	if (status != NULL) {
140 		if ((error = copyin(status, &tstat, sizeof tstat)))
141 			return error;
142 
143 		bsd_to_linux_wstat(&tstat);
144 		return copyout(&tstat, SCARG(uap, status), sizeof tstat);
145 	}
146 
147 	return 0;
148 }
149 
150 /*
151  * This is very much the same as waitpid()
152  */
153 int
154 linux_sys_wait4(p, v, retval)
155 	struct proc *p;
156 	void *v;
157 	register_t *retval;
158 {
159 	struct linux_sys_wait4_args /* {
160 		syscallarg(int) pid;
161 		syscallarg(int *) status;
162 		syscallarg(int) options;
163 		syscallarg(struct rusage *) rusage;
164 	} */ *uap = v;
165 	struct sys_wait4_args w4a;
166 	int error, *status, tstat;
167 	caddr_t sg;
168 
169 	if (SCARG(uap, status) != NULL) {
170 		sg = stackgap_init(p->p_emul);
171 		status = (int *) stackgap_alloc(&sg, sizeof status);
172 	} else
173 		status = NULL;
174 
175 	SCARG(&w4a, pid) = SCARG(uap, pid);
176 	SCARG(&w4a, status) = status;
177 	SCARG(&w4a, options) = SCARG(uap, options);
178 	SCARG(&w4a, rusage) = SCARG(uap, rusage);
179 
180 	if ((error = sys_wait4(p, &w4a, retval)))
181 		return error;
182 
183 	p->p_siglist &= ~sigmask(SIGCHLD);
184 
185 	if (status != NULL) {
186 		if ((error = copyin(status, &tstat, sizeof tstat)))
187 			return error;
188 
189 		bsd_to_linux_wstat(&tstat);
190 		return copyout(&tstat, SCARG(uap, status), sizeof tstat);
191 	}
192 
193 	return 0;
194 }
195 
196 /*
197  * This is the old brk(2) call. I don't think anything in the Linux
198  * world uses this anymore
199  */
200 int
201 linux_sys_break(p, v, retval)
202 	struct proc *p;
203 	void *v;
204 	register_t *retval;
205 {
206 #if 0
207 	struct linux_sys_brk_args /* {
208 		syscallarg(char *) nsize;
209 	} */ *uap = v;
210 #endif
211 
212 	return ENOSYS;
213 }
214 
215 /*
216  * Linux brk(2). The check if the new address is >= the old one is
217  * done in the kernel in Linux. NetBSD does it in the library.
218  */
219 int
220 linux_sys_brk(p, v, retval)
221 	struct proc *p;
222 	void *v;
223 	register_t *retval;
224 {
225 	struct linux_sys_brk_args /* {
226 		syscallarg(char *) nsize;
227 	} */ *uap = v;
228 	char *nbrk = SCARG(uap, nsize);
229 	struct sys_obreak_args oba;
230 	struct vmspace *vm = p->p_vmspace;
231 	caddr_t oldbrk;
232 
233 	oldbrk = vm->vm_daddr + ctob(vm->vm_dsize);
234 	/*
235 	 * XXX inconsistent.. Linux always returns at least the old
236 	 * brk value, but it will be page-aligned if this fails,
237 	 * and possibly not page aligned if it succeeds (the user
238 	 * supplied pointer is returned).
239 	 */
240 	SCARG(&oba, nsize) = nbrk;
241 
242 	if ((caddr_t) nbrk > vm->vm_daddr && sys_obreak(p, &oba, retval) == 0)
243 		retval[0] = (register_t)nbrk;
244 	else
245 		retval[0] = (register_t)oldbrk;
246 
247 	return 0;
248 }
249 
250 /*
251  * I wonder why Linux has gettimeofday() _and_ time().. Still, we
252  * need to deal with it.
253  */
254 int
255 linux_sys_time(p, v, retval)
256 	struct proc *p;
257 	void *v;
258 	register_t *retval;
259 {
260 	struct linux_sys_time_args /* {
261 		linux_time_t *t;
262 	} */ *uap = v;
263 	struct timeval atv;
264 	linux_time_t tt;
265 	int error;
266 
267 	microtime(&atv);
268 
269 	tt = atv.tv_sec;
270 	if (SCARG(uap, t) && (error = copyout(&tt, SCARG(uap, t), sizeof tt)))
271 		return error;
272 
273 	retval[0] = tt;
274 	return 0;
275 }
276 
277 /*
278  * Convert BSD statfs structure to Linux statfs structure.
279  * The Linux structure has less fields, and it also wants
280  * the length of a name in a dir entry in a field, which
281  * we fake (probably the wrong way).
282  */
283 static void
284 bsd_to_linux_statfs(bsp, lsp)
285 	struct statfs *bsp;
286 	struct linux_statfs *lsp;
287 {
288 
289 	lsp->l_ftype = bsp->f_type;
290 	lsp->l_fbsize = bsp->f_bsize;
291 	lsp->l_fblocks = bsp->f_blocks;
292 	lsp->l_fbfree = bsp->f_bfree;
293 	lsp->l_fbavail = bsp->f_bavail;
294 	lsp->l_ffiles = bsp->f_files;
295 	lsp->l_fffree = bsp->f_ffree;
296 	lsp->l_ffsid.val[0] = bsp->f_fsid.val[0];
297 	lsp->l_ffsid.val[1] = bsp->f_fsid.val[1];
298 	lsp->l_fnamelen = MAXNAMLEN;	/* XXX */
299 }
300 
301 /*
302  * Implement the fs stat functions. Straightforward.
303  */
304 int
305 linux_sys_statfs(p, v, retval)
306 	struct proc *p;
307 	void *v;
308 	register_t *retval;
309 {
310 	struct linux_sys_statfs_args /* {
311 		syscallarg(char *) path;
312 		syscallarg(struct linux_statfs *) sp;
313 	} */ *uap = v;
314 	struct statfs btmp, *bsp;
315 	struct linux_statfs ltmp;
316 	struct sys_statfs_args bsa;
317 	caddr_t sg;
318 	int error;
319 
320 	sg = stackgap_init(p->p_emul);
321 	bsp = (struct statfs *) stackgap_alloc(&sg, sizeof (struct statfs));
322 
323 	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
324 
325 	SCARG(&bsa, path) = SCARG(uap, path);
326 	SCARG(&bsa, buf) = bsp;
327 
328 	if ((error = sys_statfs(p, &bsa, retval)))
329 		return error;
330 
331 	if ((error = copyin((caddr_t) bsp, (caddr_t) &btmp, sizeof btmp)))
332 		return error;
333 
334 	bsd_to_linux_statfs(&btmp, &ltmp);
335 
336 	return copyout((caddr_t) &ltmp, (caddr_t) SCARG(uap, sp), sizeof ltmp);
337 }
338 
339 int
340 linux_sys_fstatfs(p, v, retval)
341 	struct proc *p;
342 	void *v;
343 	register_t *retval;
344 {
345 	struct linux_sys_fstatfs_args /* {
346 		syscallarg(int) fd;
347 		syscallarg(struct linux_statfs *) sp;
348 	} */ *uap = v;
349 	struct statfs btmp, *bsp;
350 	struct linux_statfs ltmp;
351 	struct sys_fstatfs_args bsa;
352 	caddr_t sg;
353 	int error;
354 
355 	sg = stackgap_init(p->p_emul);
356 	bsp = (struct statfs *) stackgap_alloc(&sg, sizeof (struct statfs));
357 
358 	SCARG(&bsa, fd) = SCARG(uap, fd);
359 	SCARG(&bsa, buf) = bsp;
360 
361 	if ((error = sys_fstatfs(p, &bsa, retval)))
362 		return error;
363 
364 	if ((error = copyin((caddr_t) bsp, (caddr_t) &btmp, sizeof btmp)))
365 		return error;
366 
367 	bsd_to_linux_statfs(&btmp, &ltmp);
368 
369 	return copyout((caddr_t) &ltmp, (caddr_t) SCARG(uap, sp), sizeof ltmp);
370 }
371 
372 /*
373  * uname(). Just copy the info from the various strings stored in the
374  * kernel, and put it in the Linux utsname structure. That structure
375  * is almost the same as the NetBSD one, only it has fields 65 characters
376  * long, and an extra domainname field.
377  */
378 int
379 linux_sys_uname(p, v, retval)
380 	struct proc *p;
381 	void *v;
382 	register_t *retval;
383 {
384 	struct linux_sys_uname_args /* {
385 		syscallarg(struct linux_utsname *) up;
386 	} */ *uap = v;
387 	extern char ostype[], hostname[], osrelease[], version[], machine[],
388 	    domainname[];
389 	struct linux_utsname luts;
390 	int len;
391 	char *cp;
392 
393 	strncpy(luts.l_sysname, ostype, sizeof(luts.l_sysname));
394 	strncpy(luts.l_nodename, hostname, sizeof(luts.l_nodename));
395 	strncpy(luts.l_release, osrelease, sizeof(luts.l_release));
396 	strncpy(luts.l_version, version, sizeof(luts.l_version));
397 	strncpy(luts.l_machine, machine, sizeof(luts.l_machine));
398 	strncpy(luts.l_domainname, domainname, sizeof(luts.l_domainname));
399 
400 	/* This part taken from the the uname() in libc */
401 	len = sizeof(luts.l_version);
402 	for (cp = luts.l_version; len--; ++cp)
403 		if (*cp == '\n' || *cp == '\t')
404 			if (len > 1)
405 				*cp = ' ';
406 			else
407 				*cp = '\0';
408 
409 	return copyout(&luts, SCARG(uap, up), sizeof(luts));
410 }
411 
412 int
413 linux_sys_olduname(p, v, retval)
414 	struct proc *p;
415 	void *v;
416 	register_t *retval;
417 {
418 	struct linux_sys_uname_args /* {
419 		syscallarg(struct linux_oldutsname *) up;
420 	} */ *uap = v;
421 	extern char ostype[], hostname[], osrelease[], version[], machine[];
422 	struct linux_oldutsname luts;
423 	int len;
424 	char *cp;
425 
426 	strncpy(luts.l_sysname, ostype, sizeof(luts.l_sysname));
427 	strncpy(luts.l_nodename, hostname, sizeof(luts.l_nodename));
428 	strncpy(luts.l_release, osrelease, sizeof(luts.l_release));
429 	strncpy(luts.l_version, version, sizeof(luts.l_version));
430 	strncpy(luts.l_machine, machine, sizeof(luts.l_machine));
431 
432 	/* This part taken from the the uname() in libc */
433 	len = sizeof(luts.l_version);
434 	for (cp = luts.l_version; len--; ++cp)
435 		if (*cp == '\n' || *cp == '\t')
436 			if (len > 1)
437 				*cp = ' ';
438 			else
439 				*cp = '\0';
440 
441 	return copyout(&luts, SCARG(uap, up), sizeof(luts));
442 }
443 
444 int
445 linux_sys_oldolduname(p, v, retval)
446 	struct proc *p;
447 	void *v;
448 	register_t *retval;
449 {
450 	struct linux_sys_uname_args /* {
451 		syscallarg(struct linux_oldoldutsname *) up;
452 	} */ *uap = v;
453 	extern char ostype[], hostname[], osrelease[], version[], machine[];
454 	struct linux_oldoldutsname luts;
455 	int len;
456 	char *cp;
457 
458 	strncpy(luts.l_sysname, ostype, sizeof(luts.l_sysname));
459 	strncpy(luts.l_nodename, hostname, sizeof(luts.l_nodename));
460 	strncpy(luts.l_release, osrelease, sizeof(luts.l_release));
461 	strncpy(luts.l_version, version, sizeof(luts.l_version));
462 	strncpy(luts.l_machine, machine, sizeof(luts.l_machine));
463 
464 	/* This part taken from the the uname() in libc */
465 	len = sizeof(luts.l_version);
466 	for (cp = luts.l_version; len--; ++cp)
467 		if (*cp == '\n' || *cp == '\t')
468 			if (len > 1)
469 				*cp = ' ';
470 			else
471 				*cp = '\0';
472 
473 	return copyout(&luts, SCARG(uap, up), sizeof(luts));
474 }
475 
476 /*
477  * Linux wants to pass everything to a syscall in registers. However,
478  * mmap() has 6 of them. Oops: out of register error. They just pass
479  * everything in a structure.
480  */
481 int
482 linux_sys_mmap(p, v, retval)
483 	struct proc *p;
484 	void *v;
485 	register_t *retval;
486 {
487 	struct linux_sys_mmap_args /* {
488 		syscallarg(struct linux_mmap *) lmp;
489 	} */ *uap = v;
490 	struct linux_mmap lmap;
491 	struct sys_mmap_args cma;
492 	int error, flags;
493 
494 	if ((error = copyin(SCARG(uap, lmp), &lmap, sizeof lmap)))
495 		return error;
496 
497 	flags = 0;
498 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_SHARED, MAP_SHARED);
499 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_PRIVATE, MAP_PRIVATE);
500 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_FIXED, MAP_FIXED);
501 	flags |= cvtto_bsd_mask(lmap.lm_flags, LINUX_MAP_ANON, MAP_ANON);
502 
503 	SCARG(&cma,addr) = lmap.lm_addr;
504 	SCARG(&cma,len) = lmap.lm_len;
505 	if (lmap.lm_prot & VM_PROT_WRITE) /* XXX */
506 		lmap.lm_prot |= VM_PROT_READ;
507  	SCARG(&cma,prot) = lmap.lm_prot;
508 	SCARG(&cma,flags) = flags;
509 	SCARG(&cma,fd) = lmap.lm_fd;
510 	SCARG(&cma,pad) = 0;
511 	SCARG(&cma,pos) = lmap.lm_pos;
512 
513 	return sys_mmap(p, &cma, retval);
514 }
515 
516 int
517 linux_sys_mremap(p, v, retval)
518 	struct proc *p;
519 	void *v;
520 	register_t *retval;
521 {
522 #ifdef notyet
523 	struct linux_sys_mremap_args /* {
524 		syscallarg(void *) old_address;
525 		syscallarg(size_t) old_size;
526 		syscallarg(size_t) new_size;
527 		syscallarg(u_long) flags;
528 	} */ *uap = v;
529 #endif
530 
531 	return ENOMEM;
532 }
533 
534 int
535 linux_sys_msync(p, v, retval)
536 	struct proc *p;
537 	void *v;
538 	register_t *retval;
539 {
540 	struct linux_sys_msync_args /* {
541 		syscallarg(caddr_t) addr;
542 		syscallarg(int) len;
543 		syscallarg(int) fl;
544 	} */ *uap = v;
545 
546 	struct sys_msync_args bma;
547 
548 	/* flags are ignored */
549 	SCARG(&bma, addr) = SCARG(uap, addr);
550 	SCARG(&bma, len) = SCARG(uap, len);
551 
552 	return sys_msync(p, &bma, retval);
553 }
554 
555 /*
556  * This code is partly stolen from src/lib/libc/compat-43/times.c
557  * XXX - CLK_TCK isn't declared in /sys, just in <time.h>, done here
558  */
559 
560 #define CLK_TCK 100
561 #define	CONVTCK(r)	(r.tv_sec * CLK_TCK + r.tv_usec / (1000000 / CLK_TCK))
562 
563 int
564 linux_sys_times(p, v, retval)
565 	struct proc *p;
566 	void *v;
567 	register_t *retval;
568 {
569 	struct linux_sys_times_args /* {
570 		syscallarg(struct times *) tms;
571 	} */ *uap = v;
572 	struct timeval t;
573 	struct linux_tms ltms;
574 	struct rusage ru;
575 	int error, s;
576 
577 	calcru(p, &ru.ru_utime, &ru.ru_stime, NULL);
578 	ltms.ltms_utime = CONVTCK(ru.ru_utime);
579 	ltms.ltms_stime = CONVTCK(ru.ru_stime);
580 
581 	ltms.ltms_cutime = CONVTCK(p->p_stats->p_cru.ru_utime);
582 	ltms.ltms_cstime = CONVTCK(p->p_stats->p_cru.ru_stime);
583 
584 	if ((error = copyout(&ltms, SCARG(uap, tms), sizeof ltms)))
585 		return error;
586 
587 	s = splclock();
588 	timersub(&time, &boottime, &t);
589 	splx(s);
590 
591 	retval[0] = ((linux_clock_t)(CONVTCK(t)));
592 	return 0;
593 }
594 
595 /*
596  * NetBSD passes fd[0] in retval[0], and fd[1] in retval[1].
597  * Linux directly passes the pointer.
598  */
599 int
600 linux_sys_pipe(p, v, retval)
601 	struct proc *p;
602 	void *v;
603 	register_t *retval;
604 {
605 	struct linux_sys_pipe_args /* {
606 		syscallarg(int *) pfds;
607 	} */ *uap = v;
608 	int error;
609 
610 	if ((error = sys_pipe(p, 0, retval)))
611 		return error;
612 
613 	/* Assumes register_t is an int */
614 
615 	if ((error = copyout(retval, SCARG(uap, pfds), 2 * sizeof (int))))
616 		return error;
617 
618 	retval[0] = 0;
619 	return 0;
620 }
621 
622 /*
623  * Alarm. This is a libc call which uses setitimer(2) in NetBSD.
624  * Fiddle with the timers to make it work.
625  */
626 int
627 linux_sys_alarm(p, v, retval)
628 	struct proc *p;
629 	void *v;
630 	register_t *retval;
631 {
632 	struct linux_sys_alarm_args /* {
633 		syscallarg(unsigned int) secs;
634 	} */ *uap = v;
635 	int s;
636 	struct itimerval *itp, it;
637 
638 	itp = &p->p_realtimer;
639 	s = splclock();
640 	/*
641 	 * Clear any pending timer alarms.
642 	 */
643 	untimeout(realitexpire, p);
644 	timerclear(&itp->it_interval);
645 	if (timerisset(&itp->it_value) &&
646 	    timercmp(&itp->it_value, &time, >))
647 		timersub(&itp->it_value, &time, &itp->it_value);
648 	/*
649 	 * Return how many seconds were left (rounded up)
650 	 */
651 	retval[0] = itp->it_value.tv_sec;
652 	if (itp->it_value.tv_usec)
653 		retval[0]++;
654 
655 	/*
656 	 * alarm(0) just resets the timer.
657 	 */
658 	if (SCARG(uap, secs) == 0) {
659 		timerclear(&itp->it_value);
660 		splx(s);
661 		return 0;
662 	}
663 
664 	/*
665 	 * Check the new alarm time for sanity, and set it.
666 	 */
667 	timerclear(&it.it_interval);
668 	it.it_value.tv_sec = SCARG(uap, secs);
669 	it.it_value.tv_usec = 0;
670 	if (itimerfix(&it.it_value) || itimerfix(&it.it_interval)) {
671 		splx(s);
672 		return (EINVAL);
673 	}
674 
675 	if (timerisset(&it.it_value)) {
676 		timeradd(&it.it_value, &time, &it.it_value);
677 		timeout(realitexpire, p, hzto(&it.it_value));
678 	}
679 	p->p_realtimer = it;
680 	splx(s);
681 
682 	return 0;
683 }
684 
685 /*
686  * utime(). Do conversion to things that utimes() understands,
687  * and pass it on.
688  */
689 int
690 linux_sys_utime(p, v, retval)
691 	struct proc *p;
692 	void *v;
693 	register_t *retval;
694 {
695 	struct linux_sys_utime_args /* {
696 		syscallarg(char *) path;
697 		syscallarg(struct linux_utimbuf *)times;
698 	} */ *uap = v;
699 	caddr_t sg;
700 	int error;
701 	struct sys_utimes_args ua;
702 	struct timeval tv[2], *tvp;
703 	struct linux_utimbuf lut;
704 
705 	sg = stackgap_init(p->p_emul);
706 	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
707 
708 	SCARG(&ua, path) = SCARG(uap, path);
709 
710 	if (SCARG(uap, times) != NULL) {
711 		if ((error = copyin(SCARG(uap, times), &lut, sizeof lut)))
712 			return error;
713 		tv[0].tv_usec = tv[1].tv_usec = 0;
714 		tv[0].tv_sec = lut.l_actime;
715 		tv[1].tv_sec = lut.l_modtime;
716 		tvp = (struct timeval *) stackgap_alloc(&sg, sizeof(tv));
717 		if ((error = copyout(tv, tvp, sizeof tv)))
718 			return error;
719 		SCARG(&ua, tptr) = tvp;
720 	}
721 	else
722 		SCARG(&ua, tptr) = NULL;
723 
724 	return sys_utimes(p, uap, retval);
725 }
726 
727 /*
728  * The old Linux readdir was only able to read one entry at a time,
729  * even though it had a 'count' argument. In fact, the emulation
730  * of the old call was better than the original, because it did handle
731  * the count arg properly. Don't bother with it anymore now, and use
732  * it to distinguish between old and new. The difference is that the
733  * newer one actually does multiple entries, and the reclen field
734  * really is the reclen, not the namelength.
735  */
736 int
737 linux_sys_readdir(p, v, retval)
738 	struct proc *p;
739 	void *v;
740 	register_t *retval;
741 {
742 	struct linux_sys_readdir_args /* {
743 		syscallarg(int) fd;
744 		syscallarg(struct linux_dirent *) dent;
745 		syscallarg(unsigned int) count;
746 	} */ *uap = v;
747 
748 	SCARG(uap, count) = 1;
749 	return linux_sys_getdents(p, uap, retval);
750 }
751 
752 /*
753  * Linux 'readdir' call. This code is mostly taken from the
754  * SunOS getdents call (see compat/sunos/sunos_misc.c), though
755  * an attempt has been made to keep it a little cleaner (failing
756  * miserably, because of the cruft needed if count 1 is passed).
757  *
758  * The d_off field should contain the offset of the next valid entry,
759  * but in Linux it has the offset of the entry itself. We emulate
760  * that bug here.
761  *
762  * Read in BSD-style entries, convert them, and copy them out.
763  *
764  * Note that this doesn't handle union-mounted filesystems.
765  */
766 int
767 linux_sys_getdents(p, v, retval)
768 	struct proc *p;
769 	void *v;
770 	register_t *retval;
771 {
772 	struct linux_sys_readdir_args /* {
773 		syscallarg(int) fd;
774 		syscallarg(caddr_t) dent;
775 		syscallarg(unsigned int) count;
776 	} */ *uap = v;
777 	register struct dirent *bdp;
778 	struct vnode *vp;
779 	caddr_t	inp, buf;		/* BSD-format */
780 	int len, reclen;		/* BSD-format */
781 	caddr_t outp;			/* Linux-format */
782 	int resid, linux_reclen = 0;	/* Linux-format */
783 	struct file *fp;
784 	struct uio auio;
785 	struct iovec aiov;
786 	struct linux_dirent idb;
787 	off_t off;		/* true file offset */
788 	int buflen, error, eofflag, nbytes, oldcall;
789 	struct vattr va;
790 	off_t *cookiebuf, *cookie;
791 	int ncookies;
792 
793 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
794 		return (error);
795 
796 	if ((fp->f_flag & FREAD) == 0)
797 		return (EBADF);
798 
799 	vp = (struct vnode *)fp->f_data;
800 
801 	if (vp->v_type != VDIR)	/* XXX  vnode readdir op should do this */
802 		return (EINVAL);
803 
804 	if ((error = VOP_GETATTR(vp, &va, p->p_ucred, p)))
805 		return error;
806 
807 	nbytes = SCARG(uap, count);
808 	if (nbytes == 1) {	/* emulating old, broken behaviour */
809 		nbytes = sizeof (struct linux_dirent);
810 		buflen = max(va.va_blocksize, nbytes);
811 		oldcall = 1;
812 	} else {
813 		buflen = min(MAXBSIZE, nbytes);
814 		if (buflen < va.va_blocksize)
815 			buflen = va.va_blocksize;
816 		oldcall = 0;
817 	}
818 	buf = malloc(buflen, M_TEMP, M_WAITOK);
819 	ncookies = buflen / 16;
820 	cookiebuf = malloc(ncookies * sizeof(*cookiebuf), M_TEMP, M_WAITOK);
821 
822 	VOP_LOCK(vp);
823 	off = fp->f_offset;
824 again:
825 	aiov.iov_base = buf;
826 	aiov.iov_len = buflen;
827 	auio.uio_iov = &aiov;
828 	auio.uio_iovcnt = 1;
829 	auio.uio_rw = UIO_READ;
830 	auio.uio_segflg = UIO_SYSSPACE;
831 	auio.uio_procp = p;
832 	auio.uio_resid = buflen;
833 	auio.uio_offset = off;
834 	/*
835          * First we read into the malloc'ed buffer, then
836          * we massage it into user space, one record at a time.
837          */
838 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookiebuf,
839 	    ncookies);
840 	if (error)
841 		goto out;
842 
843 	inp = buf;
844 	outp = SCARG(uap, dent);
845 	resid = nbytes;
846 	if ((len = buflen - auio.uio_resid) == 0)
847 		goto eof;
848 
849 	for (cookie = cookiebuf; len > 0; len -= reclen) {
850 		bdp = (struct dirent *)inp;
851 		reclen = bdp->d_reclen;
852 		if (reclen & 3)
853 			panic("linux_readdir");
854 		if (bdp->d_fileno == 0) {
855 			inp += reclen;	/* it is a hole; squish it out */
856 			off = *cookie++;
857 			continue;
858 		}
859 		linux_reclen = LINUX_RECLEN(&idb, bdp->d_namlen);
860 		if (reclen > len || resid < linux_reclen) {
861 			/* entry too big for buffer, so just stop */
862 			outp++;
863 			break;
864 		}
865 		/*
866 		 * Massage in place to make a Linux-shaped dirent (otherwise
867 		 * we have to worry about touching user memory outside of
868 		 * the copyout() call).
869 		 */
870 		idb.d_ino = (linux_ino_t)bdp->d_fileno;
871 		/*
872 		 * The old readdir() call misuses the offset and reclen fields.
873 		 */
874 		if (oldcall) {
875 			idb.d_off = (linux_off_t)linux_reclen;
876 			idb.d_reclen = (u_short)bdp->d_namlen;
877 		} else {
878 			if (sizeof (linux_off_t) < 4 && (off >> 32) != 0) {
879 				compat_offseterr(vp, "linux_getdents");
880 				error = EINVAL;
881 				goto out;
882 			}
883 			idb.d_off = (linux_off_t)off;
884 			idb.d_reclen = (u_short)linux_reclen;
885 		}
886 		strcpy(idb.d_name, bdp->d_name);
887 		if ((error = copyout((caddr_t)&idb, outp, linux_reclen)))
888 			goto out;
889 		/* advance past this real entry */
890 		inp += reclen;
891 		off = *cookie++;	/* each entry points to itself */
892 		/* advance output past Linux-shaped entry */
893 		outp += linux_reclen;
894 		resid -= linux_reclen;
895 		if (oldcall)
896 			break;
897 	}
898 
899 	/* if we squished out the whole block, try again */
900 	if (outp == SCARG(uap, dent))
901 		goto again;
902 	fp->f_offset = off;	/* update the vnode offset */
903 
904 	if (oldcall)
905 		nbytes = resid + linux_reclen;
906 
907 eof:
908 	*retval = nbytes - resid;
909 out:
910 	VOP_UNLOCK(vp);
911 	free(cookiebuf, M_TEMP);
912 	free(buf, M_TEMP);
913 	return error;
914 }
915 
916 /*
917  * Not sure why the arguments to this older version of select() were put
918  * into a structure, because there are 5, and that can all be handled
919  * in registers on the i386 like Linux wants to.
920  */
921 int
922 linux_sys_oldselect(p, v, retval)
923 	struct proc *p;
924 	void *v;
925 	register_t *retval;
926 {
927 	struct linux_sys_oldselect_args /* {
928 		syscallarg(struct linux_select *) lsp;
929 	} */ *uap = v;
930 	struct linux_select ls;
931 	int error;
932 
933 	if ((error = copyin(SCARG(uap, lsp), &ls, sizeof(ls))))
934 		return error;
935 
936 	return linux_select1(p, retval, ls.nfds, ls.readfds, ls.writefds,
937 	    ls.exceptfds, ls.timeout);
938 }
939 
940 /*
941  * Even when just using registers to pass arguments to syscalls you can
942  * have 5 of them on the i386. So this newer version of select() does
943  * this.
944  */
945 int
946 linux_sys_select(p, v, retval)
947 	struct proc *p;
948 	void *v;
949 	register_t *retval;
950 {
951 	struct linux_sys_select_args /* {
952 		syscallarg(int) nfds;
953 		syscallarg(fd_set *) readfds;
954 		syscallarg(fd_set *) writefds;
955 		syscallarg(fd_set *) exceptfds;
956 		syscallarg(struct timeval *) timeout;
957 	} */ *uap = v;
958 
959 	return linux_select1(p, retval, SCARG(uap, nfds), SCARG(uap, readfds),
960 	    SCARG(uap, writefds), SCARG(uap, exceptfds), SCARG(uap, timeout));
961 }
962 
963 /*
964  * Common code for the old and new versions of select(). A couple of
965  * things are important:
966  * 1) return the amount of time left in the 'timeout' parameter
967  * 2) select never returns ERESTART on Linux, always return EINTR
968  */
969 int
970 linux_select1(p, retval, nfds, readfds, writefds, exceptfds, timeout)
971 	struct proc *p;
972 	register_t *retval;
973 	int nfds;
974 	fd_set *readfds, *writefds, *exceptfds;
975 	struct timeval *timeout;
976 {
977 	struct sys_select_args bsa;
978 	struct timeval tv0, tv1, utv, *tvp;
979 	caddr_t sg;
980 	int error;
981 
982 	SCARG(&bsa, nd) = nfds;
983 	SCARG(&bsa, in) = readfds;
984 	SCARG(&bsa, ou) = writefds;
985 	SCARG(&bsa, ex) = exceptfds;
986 	SCARG(&bsa, tv) = timeout;
987 
988 	/*
989 	 * Store current time for computation of the amount of
990 	 * time left.
991 	 */
992 	if (timeout) {
993 		if ((error = copyin(timeout, &utv, sizeof(utv))))
994 			return error;
995 		if (itimerfix(&utv)) {
996 			/*
997 			 * The timeval was invalid.  Convert it to something
998 			 * valid that will act as it does under Linux.
999 			 */
1000 			sg = stackgap_init(p->p_emul);
1001 			tvp = stackgap_alloc(&sg, sizeof(utv));
1002 			utv.tv_sec += utv.tv_usec / 1000000;
1003 			utv.tv_usec %= 1000000;
1004 			if (utv.tv_usec < 0) {
1005 				utv.tv_sec -= 1;
1006 				utv.tv_usec += 1000000;
1007 			}
1008 			if (utv.tv_sec < 0)
1009 				timerclear(&utv);
1010 			if ((error = copyout(&utv, tvp, sizeof(utv))))
1011 				return error;
1012 			SCARG(&bsa, tv) = tvp;
1013 		}
1014 		microtime(&tv0);
1015 	}
1016 
1017 	error = sys_select(p, &bsa, retval);
1018 	if (error) {
1019 		/*
1020 		 * See fs/select.c in the Linux kernel.  Without this,
1021 		 * Maelstrom doesn't work.
1022 		 */
1023 		if (error == ERESTART)
1024 			error = EINTR;
1025 		return error;
1026 	}
1027 
1028 	if (timeout) {
1029 		if (*retval) {
1030 			/*
1031 			 * Compute how much time was left of the timeout,
1032 			 * by subtracting the current time and the time
1033 			 * before we started the call, and subtracting
1034 			 * that result from the user-supplied value.
1035 			 */
1036 			microtime(&tv1);
1037 			timersub(&tv1, &tv0, &tv1);
1038 			timersub(&utv, &tv1, &utv);
1039 			if (utv.tv_sec < 0)
1040 				timerclear(&utv);
1041 		} else
1042 			timerclear(&utv);
1043 		if ((error = copyout(&utv, timeout, sizeof(utv))))
1044 			return error;
1045 	}
1046 
1047 	return 0;
1048 }
1049 
1050 /*
1051  * Get the process group of a certain process. Look it up
1052  * and return the value.
1053  */
1054 int
1055 linux_sys_getpgid(p, v, retval)
1056 	struct proc *p;
1057 	void *v;
1058 	register_t *retval;
1059 {
1060 	struct linux_sys_getpgid_args /* {
1061 		syscallarg(int) pid;
1062 	} */ *uap = v;
1063 	struct proc *targp;
1064 
1065 	if (SCARG(uap, pid) != 0 && SCARG(uap, pid) != p->p_pid) {
1066 		if ((targp = pfind(SCARG(uap, pid))) == 0)
1067 			return ESRCH;
1068 	}
1069 	else
1070 		targp = p;
1071 
1072 	retval[0] = targp->p_pgid;
1073 	return 0;
1074 }
1075 
1076 /*
1077  * Set the 'personality' (emulation mode) for the current process. Only
1078  * accept the Linux personality here (0). This call is needed because
1079  * the Linux ELF crt0 issues it in an ugly kludge to make sure that
1080  * ELF binaries run in Linux mode, not SVR4 mode.
1081  */
1082 int
1083 linux_sys_personality(p, v, retval)
1084 	struct proc *p;
1085 	void *v;
1086 	register_t *retval;
1087 {
1088 	struct linux_sys_personality_args /* {
1089 		syscallarg(int) per;
1090 	} */ *uap = v;
1091 
1092 	if (SCARG(uap, per) != 0)
1093 		return EINVAL;
1094 	retval[0] = 0;
1095 	return 0;
1096 }
1097 
1098 /*
1099  * The calls are here because of type conversions.
1100  */
1101 int
1102 linux_sys_setreuid(p, v, retval)
1103 	struct proc *p;
1104 	void *v;
1105 	register_t *retval;
1106 {
1107 	struct linux_sys_setreuid_args /* {
1108 		syscallarg(int) ruid;
1109 		syscallarg(int) euid;
1110 	} */ *uap = v;
1111 	struct sys_setreuid_args bsa;
1112 
1113 	SCARG(&bsa, ruid) = ((linux_uid_t)SCARG(uap, ruid) == (linux_uid_t)-1) ?
1114 		(uid_t)-1 : SCARG(uap, ruid);
1115 	SCARG(&bsa, euid) = ((linux_uid_t)SCARG(uap, euid) == (linux_uid_t)-1) ?
1116 		(uid_t)-1 : SCARG(uap, euid);
1117 
1118 	return sys_setreuid(p, &bsa, retval);
1119 }
1120 
1121 int
1122 linux_sys_setregid(p, v, retval)
1123 	struct proc *p;
1124 	void *v;
1125 	register_t *retval;
1126 {
1127 	struct linux_sys_setregid_args /* {
1128 		syscallarg(int) rgid;
1129 		syscallarg(int) egid;
1130 	} */ *uap = v;
1131 	struct sys_setregid_args bsa;
1132 
1133 	SCARG(&bsa, rgid) = ((linux_gid_t)SCARG(uap, rgid) == (linux_gid_t)-1) ?
1134 		(uid_t)-1 : SCARG(uap, rgid);
1135 	SCARG(&bsa, egid) = ((linux_gid_t)SCARG(uap, egid) == (linux_gid_t)-1) ?
1136 		(uid_t)-1 : SCARG(uap, egid);
1137 
1138 	return sys_setregid(p, &bsa, retval);
1139 }
1140 
1141 int
1142 linux_sys_getsid(p, v, retval)
1143 	struct proc *p;
1144 	void *v;
1145 	register_t *retval;
1146 {
1147 	struct linux_sys_getsid_args /* {
1148 		syscallarg(int) pid;
1149 	} */ *uap = v;
1150 	struct proc *p1;
1151 	pid_t pid;
1152 
1153 	pid = (pid_t)SCARG(uap, pid);
1154 
1155 	if (pid == 0) {
1156 		retval[0] = (int)p->p_session;	/* XXX Oh well */
1157 		return 0;
1158 	}
1159 
1160 	p1 = pfind((int)pid);
1161 	if (p1 == NULL)
1162 		return ESRCH;
1163 
1164 	retval[0] = (int)p1->p_session;
1165 	return 0;
1166 }
1167 
1168 int
1169 linux_sys___sysctl(p, v, retval)
1170 	struct proc *p;
1171 	void *v;
1172 	register_t *retval;
1173 {
1174 	struct linux_sys___sysctl_args /* {
1175 		syscallarg(struct linux___sysctl *) lsp;
1176 	} */ *uap = v;
1177 	struct linux___sysctl ls;
1178 	struct sys___sysctl_args bsa;
1179 	int error;
1180 
1181 	if ((error = copyin(SCARG(uap, lsp), &ls, sizeof ls)))
1182 		return error;
1183 	SCARG(&bsa, name) = ls.name;
1184 	SCARG(&bsa, namelen) = ls.namelen;
1185 	SCARG(&bsa, old) = ls.old;
1186 	SCARG(&bsa, oldlenp) = ls.oldlenp;
1187 	SCARG(&bsa, new) = ls.new;
1188 	SCARG(&bsa, newlen) = ls.newlen;
1189 
1190 	return sys___sysctl(p, &bsa, retval);
1191 }
1192 
1193 int
1194 linux_sys_nice(p, v, retval)
1195 	struct proc *p;
1196 	void *v;
1197 	register_t *retval;
1198 {
1199 	struct linux_sys_nice_args /* {
1200 		syscallarg(int) incr;
1201 	} */ *uap = v;
1202         struct sys_setpriority_args bsa;
1203 
1204         SCARG(&bsa, which) = PRIO_PROCESS;
1205         SCARG(&bsa, who) = 0;
1206 	SCARG(&bsa, prio) = SCARG(uap, incr);
1207         return sys_setpriority(p, &bsa, retval);
1208 }
1209