xref: /freebsd/sys/i386/linux/linux_machdep.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*-
2  * Copyright (c) 2000 Marcel Moolenaar
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/file.h>
35 #include <sys/fcntl.h>
36 #include <sys/imgact.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/mman.h>
40 #include <sys/mutex.h>
41 #include <sys/sx.h>
42 #include <sys/priv.h>
43 #include <sys/proc.h>
44 #include <sys/queue.h>
45 #include <sys/resource.h>
46 #include <sys/resourcevar.h>
47 #include <sys/signalvar.h>
48 #include <sys/syscallsubr.h>
49 #include <sys/sysproto.h>
50 #include <sys/unistd.h>
51 #include <sys/wait.h>
52 #include <sys/sched.h>
53 
54 #include <machine/frame.h>
55 #include <machine/psl.h>
56 #include <machine/segments.h>
57 #include <machine/sysarch.h>
58 
59 #include <vm/vm.h>
60 #include <vm/pmap.h>
61 #include <vm/vm_map.h>
62 
63 #include <i386/linux/linux.h>
64 #include <i386/linux/linux_proto.h>
65 #include <compat/linux/linux_ipc.h>
66 #include <compat/linux/linux_misc.h>
67 #include <compat/linux/linux_signal.h>
68 #include <compat/linux/linux_util.h>
69 #include <compat/linux/linux_emul.h>
70 
71 #include <i386/include/pcb.h>			/* needed for pcb definition in linux_set_thread_area */
72 
73 #include "opt_posix.h"
74 
75 extern struct sysentvec elf32_freebsd_sysvec;	/* defined in i386/i386/elf_machdep.c */
76 
77 struct l_descriptor {
78 	l_uint		entry_number;
79 	l_ulong		base_addr;
80 	l_uint		limit;
81 	l_uint		seg_32bit:1;
82 	l_uint		contents:2;
83 	l_uint		read_exec_only:1;
84 	l_uint		limit_in_pages:1;
85 	l_uint		seg_not_present:1;
86 	l_uint		useable:1;
87 };
88 
89 struct l_old_select_argv {
90 	l_int		nfds;
91 	l_fd_set	*readfds;
92 	l_fd_set	*writefds;
93 	l_fd_set	*exceptfds;
94 	struct l_timeval	*timeout;
95 };
96 
97 static int	linux_mmap_common(struct thread *td, l_uintptr_t addr,
98 		    l_size_t len, l_int prot, l_int flags, l_int fd,
99 		    l_loff_t pos);
100 
101 int
102 linux_to_bsd_sigaltstack(int lsa)
103 {
104 	int bsa = 0;
105 
106 	if (lsa & LINUX_SS_DISABLE)
107 		bsa |= SS_DISABLE;
108 	if (lsa & LINUX_SS_ONSTACK)
109 		bsa |= SS_ONSTACK;
110 	return (bsa);
111 }
112 
113 int
114 bsd_to_linux_sigaltstack(int bsa)
115 {
116 	int lsa = 0;
117 
118 	if (bsa & SS_DISABLE)
119 		lsa |= LINUX_SS_DISABLE;
120 	if (bsa & SS_ONSTACK)
121 		lsa |= LINUX_SS_ONSTACK;
122 	return (lsa);
123 }
124 
125 int
126 linux_execve(struct thread *td, struct linux_execve_args *args)
127 {
128 	int error;
129 	char *newpath;
130 	struct image_args eargs;
131 
132 	LCONVPATHEXIST(td, args->path, &newpath);
133 
134 #ifdef DEBUG
135 	if (ldebug(execve))
136 		printf(ARGS(execve, "%s"), newpath);
137 #endif
138 
139 	error = exec_copyin_args(&eargs, newpath, UIO_SYSSPACE,
140 	    args->argp, args->envp);
141 	free(newpath, M_TEMP);
142 	if (error == 0)
143 		error = kern_execve(td, &eargs, NULL);
144 	if (error == 0)
145 	   	/* linux process can exec fbsd one, dont attempt
146 		 * to create emuldata for such process using
147 		 * linux_proc_init, this leads to a panic on KASSERT
148 		 * because such process has p->p_emuldata == NULL
149 		 */
150 		if (SV_PROC_ABI(td->td_proc) == SV_ABI_LINUX)
151    			error = linux_proc_init(td, 0, 0);
152 	return (error);
153 }
154 
155 struct l_ipc_kludge {
156 	struct l_msgbuf *msgp;
157 	l_long msgtyp;
158 };
159 
160 int
161 linux_ipc(struct thread *td, struct linux_ipc_args *args)
162 {
163 
164 	switch (args->what & 0xFFFF) {
165 	case LINUX_SEMOP: {
166 		struct linux_semop_args a;
167 
168 		a.semid = args->arg1;
169 		a.tsops = args->ptr;
170 		a.nsops = args->arg2;
171 		return (linux_semop(td, &a));
172 	}
173 	case LINUX_SEMGET: {
174 		struct linux_semget_args a;
175 
176 		a.key = args->arg1;
177 		a.nsems = args->arg2;
178 		a.semflg = args->arg3;
179 		return (linux_semget(td, &a));
180 	}
181 	case LINUX_SEMCTL: {
182 		struct linux_semctl_args a;
183 		int error;
184 
185 		a.semid = args->arg1;
186 		a.semnum = args->arg2;
187 		a.cmd = args->arg3;
188 		error = copyin(args->ptr, &a.arg, sizeof(a.arg));
189 		if (error)
190 			return (error);
191 		return (linux_semctl(td, &a));
192 	}
193 	case LINUX_MSGSND: {
194 		struct linux_msgsnd_args a;
195 
196 		a.msqid = args->arg1;
197 		a.msgp = args->ptr;
198 		a.msgsz = args->arg2;
199 		a.msgflg = args->arg3;
200 		return (linux_msgsnd(td, &a));
201 	}
202 	case LINUX_MSGRCV: {
203 		struct linux_msgrcv_args a;
204 
205 		a.msqid = args->arg1;
206 		a.msgsz = args->arg2;
207 		a.msgflg = args->arg3;
208 		if ((args->what >> 16) == 0) {
209 			struct l_ipc_kludge tmp;
210 			int error;
211 
212 			if (args->ptr == NULL)
213 				return (EINVAL);
214 			error = copyin(args->ptr, &tmp, sizeof(tmp));
215 			if (error)
216 				return (error);
217 			a.msgp = tmp.msgp;
218 			a.msgtyp = tmp.msgtyp;
219 		} else {
220 			a.msgp = args->ptr;
221 			a.msgtyp = args->arg5;
222 		}
223 		return (linux_msgrcv(td, &a));
224 	}
225 	case LINUX_MSGGET: {
226 		struct linux_msgget_args a;
227 
228 		a.key = args->arg1;
229 		a.msgflg = args->arg2;
230 		return (linux_msgget(td, &a));
231 	}
232 	case LINUX_MSGCTL: {
233 		struct linux_msgctl_args a;
234 
235 		a.msqid = args->arg1;
236 		a.cmd = args->arg2;
237 		a.buf = args->ptr;
238 		return (linux_msgctl(td, &a));
239 	}
240 	case LINUX_SHMAT: {
241 		struct linux_shmat_args a;
242 
243 		a.shmid = args->arg1;
244 		a.shmaddr = args->ptr;
245 		a.shmflg = args->arg2;
246 		a.raddr = (l_ulong *)args->arg3;
247 		return (linux_shmat(td, &a));
248 	}
249 	case LINUX_SHMDT: {
250 		struct linux_shmdt_args a;
251 
252 		a.shmaddr = args->ptr;
253 		return (linux_shmdt(td, &a));
254 	}
255 	case LINUX_SHMGET: {
256 		struct linux_shmget_args a;
257 
258 		a.key = args->arg1;
259 		a.size = args->arg2;
260 		a.shmflg = args->arg3;
261 		return (linux_shmget(td, &a));
262 	}
263 	case LINUX_SHMCTL: {
264 		struct linux_shmctl_args a;
265 
266 		a.shmid = args->arg1;
267 		a.cmd = args->arg2;
268 		a.buf = args->ptr;
269 		return (linux_shmctl(td, &a));
270 	}
271 	default:
272 		break;
273 	}
274 
275 	return (EINVAL);
276 }
277 
278 int
279 linux_old_select(struct thread *td, struct linux_old_select_args *args)
280 {
281 	struct l_old_select_argv linux_args;
282 	struct linux_select_args newsel;
283 	int error;
284 
285 #ifdef DEBUG
286 	if (ldebug(old_select))
287 		printf(ARGS(old_select, "%p"), args->ptr);
288 #endif
289 
290 	error = copyin(args->ptr, &linux_args, sizeof(linux_args));
291 	if (error)
292 		return (error);
293 
294 	newsel.nfds = linux_args.nfds;
295 	newsel.readfds = linux_args.readfds;
296 	newsel.writefds = linux_args.writefds;
297 	newsel.exceptfds = linux_args.exceptfds;
298 	newsel.timeout = linux_args.timeout;
299 	return (linux_select(td, &newsel));
300 }
301 
302 int
303 linux_set_cloned_tls(struct thread *td, void *desc)
304 {
305 	struct segment_descriptor sd;
306 	struct l_user_desc info;
307 	int idx, error;
308 	int a[2];
309 
310 	error = copyin(desc, &info, sizeof(struct l_user_desc));
311 	if (error) {
312 		printf(LMSG("copyin failed!"));
313 	} else {
314 		idx = info.entry_number;
315 
316 		/*
317 		 * looks like we're getting the idx we returned
318 		 * in the set_thread_area() syscall
319 		 */
320 		if (idx != 6 && idx != 3) {
321 			printf(LMSG("resetting idx!"));
322 			idx = 3;
323 		}
324 
325 		/* this doesnt happen in practice */
326 		if (idx == 6) {
327 	   		/* we might copy out the entry_number as 3 */
328 		   	info.entry_number = 3;
329 			error = copyout(&info, desc, sizeof(struct l_user_desc));
330 			if (error)
331 				printf(LMSG("copyout failed!"));
332 		}
333 
334 		a[0] = LINUX_LDT_entry_a(&info);
335 		a[1] = LINUX_LDT_entry_b(&info);
336 
337 		memcpy(&sd, &a, sizeof(a));
338 #ifdef DEBUG
339 		if (ldebug(clone))
340 			printf("Segment created in clone with "
341 			"CLONE_SETTLS: lobase: %x, hibase: %x, "
342 			"lolimit: %x, hilimit: %x, type: %i, "
343 			"dpl: %i, p: %i, xx: %i, def32: %i, "
344 			"gran: %i\n", sd.sd_lobase, sd.sd_hibase,
345 			sd.sd_lolimit, sd.sd_hilimit, sd.sd_type,
346 			sd.sd_dpl, sd.sd_p, sd.sd_xx,
347 			sd.sd_def32, sd.sd_gran);
348 #endif
349 
350 		/* set %gs */
351 		td->td_pcb->pcb_gsd = sd;
352 		td->td_pcb->pcb_gs = GSEL(GUGS_SEL, SEL_UPL);
353 	}
354 
355 	return (error);
356 }
357 
358 int
359 linux_set_upcall_kse(struct thread *td, register_t stack)
360 {
361 
362 	td->td_frame->tf_esp = stack;
363 
364 	return (0);
365 }
366 
367 #define STACK_SIZE  (2 * 1024 * 1024)
368 #define GUARD_SIZE  (4 * PAGE_SIZE)
369 
370 int
371 linux_mmap2(struct thread *td, struct linux_mmap2_args *args)
372 {
373 
374 #ifdef DEBUG
375 	if (ldebug(mmap2))
376 		printf(ARGS(mmap2, "%p, %d, %d, 0x%08x, %d, %d"),
377 		    (void *)args->addr, args->len, args->prot,
378 		    args->flags, args->fd, args->pgoff);
379 #endif
380 
381 	return (linux_mmap_common(td, args->addr, args->len, args->prot,
382 		args->flags, args->fd, (uint64_t)(uint32_t)args->pgoff *
383 		PAGE_SIZE));
384 }
385 
386 int
387 linux_mmap(struct thread *td, struct linux_mmap_args *args)
388 {
389 	int error;
390 	struct l_mmap_argv linux_args;
391 
392 	error = copyin(args->ptr, &linux_args, sizeof(linux_args));
393 	if (error)
394 		return (error);
395 
396 #ifdef DEBUG
397 	if (ldebug(mmap))
398 		printf(ARGS(mmap, "%p, %d, %d, 0x%08x, %d, %d"),
399 		    (void *)linux_args.addr, linux_args.len, linux_args.prot,
400 		    linux_args.flags, linux_args.fd, linux_args.pgoff);
401 #endif
402 
403 	return (linux_mmap_common(td, linux_args.addr, linux_args.len,
404 	    linux_args.prot, linux_args.flags, linux_args.fd,
405 	    (uint32_t)linux_args.pgoff));
406 }
407 
408 static int
409 linux_mmap_common(struct thread *td, l_uintptr_t addr, l_size_t len, l_int prot,
410     l_int flags, l_int fd, l_loff_t pos)
411 {
412 	struct proc *p = td->td_proc;
413 	struct mmap_args /* {
414 		caddr_t addr;
415 		size_t len;
416 		int prot;
417 		int flags;
418 		int fd;
419 		long pad;
420 		off_t pos;
421 	} */ bsd_args;
422 	int error;
423 	struct file *fp;
424 
425 	error = 0;
426 	bsd_args.flags = 0;
427 	fp = NULL;
428 
429 	/*
430 	 * Linux mmap(2):
431 	 * You must specify exactly one of MAP_SHARED and MAP_PRIVATE
432 	 */
433 	if (!((flags & LINUX_MAP_SHARED) ^ (flags & LINUX_MAP_PRIVATE)))
434 		return (EINVAL);
435 
436 	if (flags & LINUX_MAP_SHARED)
437 		bsd_args.flags |= MAP_SHARED;
438 	if (flags & LINUX_MAP_PRIVATE)
439 		bsd_args.flags |= MAP_PRIVATE;
440 	if (flags & LINUX_MAP_FIXED)
441 		bsd_args.flags |= MAP_FIXED;
442 	if (flags & LINUX_MAP_ANON) {
443 		/* Enforce pos to be on page boundary, then ignore. */
444 		if ((pos & PAGE_MASK) != 0)
445 			return (EINVAL);
446 		pos = 0;
447 		bsd_args.flags |= MAP_ANON;
448 	} else
449 		bsd_args.flags |= MAP_NOSYNC;
450 	if (flags & LINUX_MAP_GROWSDOWN)
451 		bsd_args.flags |= MAP_STACK;
452 
453 	/*
454 	 * PROT_READ, PROT_WRITE, or PROT_EXEC implies PROT_READ and PROT_EXEC
455 	 * on Linux/i386. We do this to ensure maximum compatibility.
456 	 * Linux/ia64 does the same in i386 emulation mode.
457 	 */
458 	bsd_args.prot = prot;
459 	if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
460 		bsd_args.prot |= PROT_READ | PROT_EXEC;
461 
462 	/* Linux does not check file descriptor when MAP_ANONYMOUS is set. */
463 	bsd_args.fd = (bsd_args.flags & MAP_ANON) ? -1 : fd;
464 	if (bsd_args.fd != -1) {
465 		/*
466 		 * Linux follows Solaris mmap(2) description:
467 		 * The file descriptor fildes is opened with
468 		 * read permission, regardless of the
469 		 * protection options specified.
470 		 */
471 
472 		if ((error = fget(td, bsd_args.fd, &fp)) != 0)
473 			return (error);
474 		if (fp->f_type != DTYPE_VNODE) {
475 			fdrop(fp, td);
476 			return (EINVAL);
477 		}
478 
479 		/* Linux mmap() just fails for O_WRONLY files */
480 		if (!(fp->f_flag & FREAD)) {
481 			fdrop(fp, td);
482 			return (EACCES);
483 		}
484 
485 		fdrop(fp, td);
486 	}
487 
488 	if (flags & LINUX_MAP_GROWSDOWN) {
489 		/*
490 		 * The Linux MAP_GROWSDOWN option does not limit auto
491 		 * growth of the region.  Linux mmap with this option
492 		 * takes as addr the inital BOS, and as len, the initial
493 		 * region size.  It can then grow down from addr without
494 		 * limit.  However, linux threads has an implicit internal
495 		 * limit to stack size of STACK_SIZE.  Its just not
496 		 * enforced explicitly in linux.  But, here we impose
497 		 * a limit of (STACK_SIZE - GUARD_SIZE) on the stack
498 		 * region, since we can do this with our mmap.
499 		 *
500 		 * Our mmap with MAP_STACK takes addr as the maximum
501 		 * downsize limit on BOS, and as len the max size of
502 		 * the region.  It them maps the top SGROWSIZ bytes,
503 		 * and auto grows the region down, up to the limit
504 		 * in addr.
505 		 *
506 		 * If we don't use the MAP_STACK option, the effect
507 		 * of this code is to allocate a stack region of a
508 		 * fixed size of (STACK_SIZE - GUARD_SIZE).
509 		 */
510 
511 		if ((caddr_t)PTRIN(addr) + len > p->p_vmspace->vm_maxsaddr) {
512 			/*
513 			 * Some linux apps will attempt to mmap
514 			 * thread stacks near the top of their
515 			 * address space.  If their TOS is greater
516 			 * than vm_maxsaddr, vm_map_growstack()
517 			 * will confuse the thread stack with the
518 			 * process stack and deliver a SEGV if they
519 			 * attempt to grow the thread stack past their
520 			 * current stacksize rlimit.  To avoid this,
521 			 * adjust vm_maxsaddr upwards to reflect
522 			 * the current stacksize rlimit rather
523 			 * than the maximum possible stacksize.
524 			 * It would be better to adjust the
525 			 * mmap'ed region, but some apps do not check
526 			 * mmap's return value.
527 			 */
528 			PROC_LOCK(p);
529 			p->p_vmspace->vm_maxsaddr = (char *)USRSTACK -
530 			    lim_cur(p, RLIMIT_STACK);
531 			PROC_UNLOCK(p);
532 		}
533 
534 		/*
535 		 * This gives us our maximum stack size and a new BOS.
536 		 * If we're using VM_STACK, then mmap will just map
537 		 * the top SGROWSIZ bytes, and let the stack grow down
538 		 * to the limit at BOS.  If we're not using VM_STACK
539 		 * we map the full stack, since we don't have a way
540 		 * to autogrow it.
541 		 */
542 		if (len > STACK_SIZE - GUARD_SIZE) {
543 			bsd_args.addr = (caddr_t)PTRIN(addr);
544 			bsd_args.len = len;
545 		} else {
546 			bsd_args.addr = (caddr_t)PTRIN(addr) -
547 			    (STACK_SIZE - GUARD_SIZE - len);
548 			bsd_args.len = STACK_SIZE - GUARD_SIZE;
549 		}
550 	} else {
551 		bsd_args.addr = (caddr_t)PTRIN(addr);
552 		bsd_args.len  = len;
553 	}
554 	bsd_args.pos = pos;
555 
556 #ifdef DEBUG
557 	if (ldebug(mmap))
558 		printf("-> %s(%p, %d, %d, 0x%08x, %d, 0x%x)\n",
559 		    __func__,
560 		    (void *)bsd_args.addr, bsd_args.len, bsd_args.prot,
561 		    bsd_args.flags, bsd_args.fd, (int)bsd_args.pos);
562 #endif
563 	error = mmap(td, &bsd_args);
564 #ifdef DEBUG
565 	if (ldebug(mmap))
566 		printf("-> %s() return: 0x%x (0x%08x)\n",
567 			__func__, error, (u_int)td->td_retval[0]);
568 #endif
569 	return (error);
570 }
571 
572 int
573 linux_mprotect(struct thread *td, struct linux_mprotect_args *uap)
574 {
575 	struct mprotect_args bsd_args;
576 
577 	bsd_args.addr = uap->addr;
578 	bsd_args.len = uap->len;
579 	bsd_args.prot = uap->prot;
580 	if (bsd_args.prot & (PROT_READ | PROT_WRITE | PROT_EXEC))
581 		bsd_args.prot |= PROT_READ | PROT_EXEC;
582 	return (mprotect(td, &bsd_args));
583 }
584 
585 int
586 linux_pipe(struct thread *td, struct linux_pipe_args *args)
587 {
588 	int error;
589 	int fildes[2];
590 
591 #ifdef DEBUG
592 	if (ldebug(pipe))
593 		printf(ARGS(pipe, "*"));
594 #endif
595 
596 	error = kern_pipe(td, fildes);
597 	if (error)
598 		return (error);
599 
600 	/* XXX: Close descriptors on error. */
601 	return (copyout(fildes, args->pipefds, sizeof fildes));
602 }
603 
604 int
605 linux_ioperm(struct thread *td, struct linux_ioperm_args *args)
606 {
607 	int error;
608 	struct i386_ioperm_args iia;
609 
610 	iia.start = args->start;
611 	iia.length = args->length;
612 	iia.enable = args->enable;
613 	error = i386_set_ioperm(td, &iia);
614 	return (error);
615 }
616 
617 int
618 linux_iopl(struct thread *td, struct linux_iopl_args *args)
619 {
620 	int error;
621 
622 	if (args->level < 0 || args->level > 3)
623 		return (EINVAL);
624 	if ((error = priv_check(td, PRIV_IO)) != 0)
625 		return (error);
626 	if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
627 		return (error);
628 	td->td_frame->tf_eflags = (td->td_frame->tf_eflags & ~PSL_IOPL) |
629 	    (args->level * (PSL_IOPL / 3));
630 	return (0);
631 }
632 
633 int
634 linux_modify_ldt(struct thread *td, struct linux_modify_ldt_args *uap)
635 {
636 	int error;
637 	struct i386_ldt_args ldt;
638 	struct l_descriptor ld;
639 	union descriptor desc;
640 	int size, written;
641 
642 	switch (uap->func) {
643 	case 0x00: /* read_ldt */
644 		ldt.start = 0;
645 		ldt.descs = uap->ptr;
646 		ldt.num = uap->bytecount / sizeof(union descriptor);
647 		error = i386_get_ldt(td, &ldt);
648 		td->td_retval[0] *= sizeof(union descriptor);
649 		break;
650 	case 0x02: /* read_default_ldt = 0 */
651 		size = 5*sizeof(struct l_desc_struct);
652 		if (size > uap->bytecount)
653 			size = uap->bytecount;
654 		for (written = error = 0; written < size && error == 0; written++)
655 			error = subyte((char *)uap->ptr + written, 0);
656 		td->td_retval[0] = written;
657 		break;
658 	case 0x01: /* write_ldt */
659 	case 0x11: /* write_ldt */
660 		if (uap->bytecount != sizeof(ld))
661 			return (EINVAL);
662 
663 		error = copyin(uap->ptr, &ld, sizeof(ld));
664 		if (error)
665 			return (error);
666 
667 		ldt.start = ld.entry_number;
668 		ldt.descs = &desc;
669 		ldt.num = 1;
670 		desc.sd.sd_lolimit = (ld.limit & 0x0000ffff);
671 		desc.sd.sd_hilimit = (ld.limit & 0x000f0000) >> 16;
672 		desc.sd.sd_lobase = (ld.base_addr & 0x00ffffff);
673 		desc.sd.sd_hibase = (ld.base_addr & 0xff000000) >> 24;
674 		desc.sd.sd_type = SDT_MEMRO | ((ld.read_exec_only ^ 1) << 1) |
675 			(ld.contents << 2);
676 		desc.sd.sd_dpl = 3;
677 		desc.sd.sd_p = (ld.seg_not_present ^ 1);
678 		desc.sd.sd_xx = 0;
679 		desc.sd.sd_def32 = ld.seg_32bit;
680 		desc.sd.sd_gran = ld.limit_in_pages;
681 		error = i386_set_ldt(td, &ldt, &desc);
682 		break;
683 	default:
684 		error = ENOSYS;
685 		break;
686 	}
687 
688 	if (error == EOPNOTSUPP) {
689 		printf("linux: modify_ldt needs kernel option USER_LDT\n");
690 		error = ENOSYS;
691 	}
692 
693 	return (error);
694 }
695 
696 int
697 linux_sigaction(struct thread *td, struct linux_sigaction_args *args)
698 {
699 	l_osigaction_t osa;
700 	l_sigaction_t act, oact;
701 	int error;
702 
703 #ifdef DEBUG
704 	if (ldebug(sigaction))
705 		printf(ARGS(sigaction, "%d, %p, %p"),
706 		    args->sig, (void *)args->nsa, (void *)args->osa);
707 #endif
708 
709 	if (args->nsa != NULL) {
710 		error = copyin(args->nsa, &osa, sizeof(l_osigaction_t));
711 		if (error)
712 			return (error);
713 		act.lsa_handler = osa.lsa_handler;
714 		act.lsa_flags = osa.lsa_flags;
715 		act.lsa_restorer = osa.lsa_restorer;
716 		LINUX_SIGEMPTYSET(act.lsa_mask);
717 		act.lsa_mask.__bits[0] = osa.lsa_mask;
718 	}
719 
720 	error = linux_do_sigaction(td, args->sig, args->nsa ? &act : NULL,
721 	    args->osa ? &oact : NULL);
722 
723 	if (args->osa != NULL && !error) {
724 		osa.lsa_handler = oact.lsa_handler;
725 		osa.lsa_flags = oact.lsa_flags;
726 		osa.lsa_restorer = oact.lsa_restorer;
727 		osa.lsa_mask = oact.lsa_mask.__bits[0];
728 		error = copyout(&osa, args->osa, sizeof(l_osigaction_t));
729 	}
730 
731 	return (error);
732 }
733 
734 /*
735  * Linux has two extra args, restart and oldmask.  We dont use these,
736  * but it seems that "restart" is actually a context pointer that
737  * enables the signal to happen with a different register set.
738  */
739 int
740 linux_sigsuspend(struct thread *td, struct linux_sigsuspend_args *args)
741 {
742 	sigset_t sigmask;
743 	l_sigset_t mask;
744 
745 #ifdef DEBUG
746 	if (ldebug(sigsuspend))
747 		printf(ARGS(sigsuspend, "%08lx"), (unsigned long)args->mask);
748 #endif
749 
750 	LINUX_SIGEMPTYSET(mask);
751 	mask.__bits[0] = args->mask;
752 	linux_to_bsd_sigset(&mask, &sigmask);
753 	return (kern_sigsuspend(td, sigmask));
754 }
755 
756 int
757 linux_rt_sigsuspend(struct thread *td, struct linux_rt_sigsuspend_args *uap)
758 {
759 	l_sigset_t lmask;
760 	sigset_t sigmask;
761 	int error;
762 
763 #ifdef DEBUG
764 	if (ldebug(rt_sigsuspend))
765 		printf(ARGS(rt_sigsuspend, "%p, %d"),
766 		    (void *)uap->newset, uap->sigsetsize);
767 #endif
768 
769 	if (uap->sigsetsize != sizeof(l_sigset_t))
770 		return (EINVAL);
771 
772 	error = copyin(uap->newset, &lmask, sizeof(l_sigset_t));
773 	if (error)
774 		return (error);
775 
776 	linux_to_bsd_sigset(&lmask, &sigmask);
777 	return (kern_sigsuspend(td, sigmask));
778 }
779 
780 int
781 linux_pause(struct thread *td, struct linux_pause_args *args)
782 {
783 	struct proc *p = td->td_proc;
784 	sigset_t sigmask;
785 
786 #ifdef DEBUG
787 	if (ldebug(pause))
788 		printf(ARGS(pause, ""));
789 #endif
790 
791 	PROC_LOCK(p);
792 	sigmask = td->td_sigmask;
793 	PROC_UNLOCK(p);
794 	return (kern_sigsuspend(td, sigmask));
795 }
796 
797 int
798 linux_sigaltstack(struct thread *td, struct linux_sigaltstack_args *uap)
799 {
800 	stack_t ss, oss;
801 	l_stack_t lss;
802 	int error;
803 
804 #ifdef DEBUG
805 	if (ldebug(sigaltstack))
806 		printf(ARGS(sigaltstack, "%p, %p"), uap->uss, uap->uoss);
807 #endif
808 
809 	if (uap->uss != NULL) {
810 		error = copyin(uap->uss, &lss, sizeof(l_stack_t));
811 		if (error)
812 			return (error);
813 
814 		ss.ss_sp = lss.ss_sp;
815 		ss.ss_size = lss.ss_size;
816 		ss.ss_flags = linux_to_bsd_sigaltstack(lss.ss_flags);
817 	}
818 	error = kern_sigaltstack(td, (uap->uss != NULL) ? &ss : NULL,
819 	    (uap->uoss != NULL) ? &oss : NULL);
820 	if (!error && uap->uoss != NULL) {
821 		lss.ss_sp = oss.ss_sp;
822 		lss.ss_size = oss.ss_size;
823 		lss.ss_flags = bsd_to_linux_sigaltstack(oss.ss_flags);
824 		error = copyout(&lss, uap->uoss, sizeof(l_stack_t));
825 	}
826 
827 	return (error);
828 }
829 
830 int
831 linux_ftruncate64(struct thread *td, struct linux_ftruncate64_args *args)
832 {
833 	struct ftruncate_args sa;
834 
835 #ifdef DEBUG
836 	if (ldebug(ftruncate64))
837 		printf(ARGS(ftruncate64, "%u, %jd"), args->fd,
838 		    (intmax_t)args->length);
839 #endif
840 
841 	sa.fd = args->fd;
842 	sa.length = args->length;
843 	return ftruncate(td, &sa);
844 }
845 
846 int
847 linux_set_thread_area(struct thread *td, struct linux_set_thread_area_args *args)
848 {
849 	struct l_user_desc info;
850 	int error;
851 	int idx;
852 	int a[2];
853 	struct segment_descriptor sd;
854 
855 	error = copyin(args->desc, &info, sizeof(struct l_user_desc));
856 	if (error)
857 		return (error);
858 
859 #ifdef DEBUG
860 	if (ldebug(set_thread_area))
861 	   	printf(ARGS(set_thread_area, "%i, %x, %x, %i, %i, %i, %i, %i, %i\n"),
862 		      info.entry_number,
863       		      info.base_addr,
864       		      info.limit,
865       		      info.seg_32bit,
866 		      info.contents,
867       		      info.read_exec_only,
868       		      info.limit_in_pages,
869       		      info.seg_not_present,
870       		      info.useable);
871 #endif
872 
873 	idx = info.entry_number;
874 	/*
875 	 * Semantics of linux version: every thread in the system has array of
876 	 * 3 tls descriptors. 1st is GLIBC TLS, 2nd is WINE, 3rd unknown. This
877 	 * syscall loads one of the selected tls decriptors with a value and
878 	 * also loads GDT descriptors 6, 7 and 8 with the content of the
879 	 * per-thread descriptors.
880 	 *
881 	 * Semantics of fbsd version: I think we can ignore that linux has 3
882 	 * per-thread descriptors and use just the 1st one. The tls_array[]
883 	 * is used only in set/get-thread_area() syscalls and for loading the
884 	 * GDT descriptors. In fbsd we use just one GDT descriptor for TLS so
885 	 * we will load just one.
886 	 *
887 	 * XXX: this doesn't work when a user space process tries to use more
888 	 * than 1 TLS segment. Comment in the linux sources says wine might do
889 	 * this.
890 	 */
891 
892 	/*
893 	 * we support just GLIBC TLS now
894 	 * we should let 3 proceed as well because we use this segment so
895 	 * if code does two subsequent calls it should succeed
896 	 */
897 	if (idx != 6 && idx != -1 && idx != 3)
898 		return (EINVAL);
899 
900 	/*
901 	 * we have to copy out the GDT entry we use
902 	 * FreeBSD uses GDT entry #3 for storing %gs so load that
903 	 *
904 	 * XXX: what if a user space program doesn't check this value and tries
905 	 * to use 6, 7 or 8?
906 	 */
907 	idx = info.entry_number = 3;
908 	error = copyout(&info, args->desc, sizeof(struct l_user_desc));
909 	if (error)
910 		return (error);
911 
912 	if (LINUX_LDT_empty(&info)) {
913 		a[0] = 0;
914 		a[1] = 0;
915 	} else {
916 		a[0] = LINUX_LDT_entry_a(&info);
917 		a[1] = LINUX_LDT_entry_b(&info);
918 	}
919 
920 	memcpy(&sd, &a, sizeof(a));
921 #ifdef DEBUG
922 	if (ldebug(set_thread_area))
923 	   	printf("Segment created in set_thread_area: lobase: %x, hibase: %x, lolimit: %x, hilimit: %x, type: %i, dpl: %i, p: %i, xx: %i, def32: %i, gran: %i\n", sd.sd_lobase,
924 			sd.sd_hibase,
925 			sd.sd_lolimit,
926 			sd.sd_hilimit,
927 			sd.sd_type,
928 			sd.sd_dpl,
929 			sd.sd_p,
930 			sd.sd_xx,
931 			sd.sd_def32,
932 			sd.sd_gran);
933 #endif
934 
935 	/* this is taken from i386 version of cpu_set_user_tls() */
936 	critical_enter();
937 	/* set %gs */
938 	td->td_pcb->pcb_gsd = sd;
939 	PCPU_GET(fsgs_gdt)[1] = sd;
940 	load_gs(GSEL(GUGS_SEL, SEL_UPL));
941 	critical_exit();
942 
943 	return (0);
944 }
945 
946 int
947 linux_get_thread_area(struct thread *td, struct linux_get_thread_area_args *args)
948 {
949 
950 	struct l_user_desc info;
951 	int error;
952 	int idx;
953 	struct l_desc_struct desc;
954 	struct segment_descriptor sd;
955 
956 #ifdef DEBUG
957 	if (ldebug(get_thread_area))
958 		printf(ARGS(get_thread_area, "%p"), args->desc);
959 #endif
960 
961 	error = copyin(args->desc, &info, sizeof(struct l_user_desc));
962 	if (error)
963 		return (error);
964 
965 	idx = info.entry_number;
966 	/* XXX: I am not sure if we want 3 to be allowed too. */
967 	if (idx != 6 && idx != 3)
968 		return (EINVAL);
969 
970 	idx = 3;
971 
972 	memset(&info, 0, sizeof(info));
973 
974 	sd = PCPU_GET(fsgs_gdt)[1];
975 
976 	memcpy(&desc, &sd, sizeof(desc));
977 
978 	info.entry_number = idx;
979 	info.base_addr = LINUX_GET_BASE(&desc);
980 	info.limit = LINUX_GET_LIMIT(&desc);
981 	info.seg_32bit = LINUX_GET_32BIT(&desc);
982 	info.contents = LINUX_GET_CONTENTS(&desc);
983 	info.read_exec_only = !LINUX_GET_WRITABLE(&desc);
984 	info.limit_in_pages = LINUX_GET_LIMIT_PAGES(&desc);
985 	info.seg_not_present = !LINUX_GET_PRESENT(&desc);
986 	info.useable = LINUX_GET_USEABLE(&desc);
987 
988 	error = copyout(&info, args->desc, sizeof(struct l_user_desc));
989 	if (error)
990 	   	return (EFAULT);
991 
992 	return (0);
993 }
994 
995 /* copied from kern/kern_time.c */
996 int
997 linux_timer_create(struct thread *td, struct linux_timer_create_args *args)
998 {
999    	return ktimer_create(td, (struct ktimer_create_args *) args);
1000 }
1001 
1002 int
1003 linux_timer_settime(struct thread *td, struct linux_timer_settime_args *args)
1004 {
1005    	return ktimer_settime(td, (struct ktimer_settime_args *) args);
1006 }
1007 
1008 int
1009 linux_timer_gettime(struct thread *td, struct linux_timer_gettime_args *args)
1010 {
1011    	return ktimer_gettime(td, (struct ktimer_gettime_args *) args);
1012 }
1013 
1014 int
1015 linux_timer_getoverrun(struct thread *td, struct linux_timer_getoverrun_args *args)
1016 {
1017    	return ktimer_getoverrun(td, (struct ktimer_getoverrun_args *) args);
1018 }
1019 
1020 int
1021 linux_timer_delete(struct thread *td, struct linux_timer_delete_args *args)
1022 {
1023    	return ktimer_delete(td, (struct ktimer_delete_args *) args);
1024 }
1025 
1026 /* XXX: this wont work with module - convert it */
1027 int
1028 linux_mq_open(struct thread *td, struct linux_mq_open_args *args)
1029 {
1030 #ifdef P1003_1B_MQUEUE
1031    	return kmq_open(td, (struct kmq_open_args *) args);
1032 #else
1033 	return (ENOSYS);
1034 #endif
1035 }
1036 
1037 int
1038 linux_mq_unlink(struct thread *td, struct linux_mq_unlink_args *args)
1039 {
1040 #ifdef P1003_1B_MQUEUE
1041    	return kmq_unlink(td, (struct kmq_unlink_args *) args);
1042 #else
1043 	return (ENOSYS);
1044 #endif
1045 }
1046 
1047 int
1048 linux_mq_timedsend(struct thread *td, struct linux_mq_timedsend_args *args)
1049 {
1050 #ifdef P1003_1B_MQUEUE
1051    	return kmq_timedsend(td, (struct kmq_timedsend_args *) args);
1052 #else
1053 	return (ENOSYS);
1054 #endif
1055 }
1056 
1057 int
1058 linux_mq_timedreceive(struct thread *td, struct linux_mq_timedreceive_args *args)
1059 {
1060 #ifdef P1003_1B_MQUEUE
1061    	return kmq_timedreceive(td, (struct kmq_timedreceive_args *) args);
1062 #else
1063 	return (ENOSYS);
1064 #endif
1065 }
1066 
1067 int
1068 linux_mq_notify(struct thread *td, struct linux_mq_notify_args *args)
1069 {
1070 #ifdef P1003_1B_MQUEUE
1071 	return kmq_notify(td, (struct kmq_notify_args *) args);
1072 #else
1073 	return (ENOSYS);
1074 #endif
1075 }
1076 
1077 int
1078 linux_mq_getsetattr(struct thread *td, struct linux_mq_getsetattr_args *args)
1079 {
1080 #ifdef P1003_1B_MQUEUE
1081    	return kmq_setattr(td, (struct kmq_setattr_args *) args);
1082 #else
1083 	return (ENOSYS);
1084 #endif
1085 }
1086 
1087 int
1088 linux_wait4(struct thread *td, struct linux_wait4_args *args)
1089 {
1090 	int error, options;
1091 	struct rusage ru, *rup;
1092 
1093 #ifdef DEBUG
1094 	if (ldebug(wait4))
1095 		printf(ARGS(wait4, "%d, %p, %d, %p"),
1096 		    args->pid, (void *)args->status, args->options,
1097 		    (void *)args->rusage);
1098 #endif
1099 
1100 	options = (args->options & (WNOHANG | WUNTRACED));
1101 	/* WLINUXCLONE should be equal to __WCLONE, but we make sure */
1102 	if (args->options & __WCLONE)
1103 		options |= WLINUXCLONE;
1104 
1105 	if (args->rusage != NULL)
1106 		rup = &ru;
1107 	else
1108 		rup = NULL;
1109 	error = linux_common_wait(td, args->pid, args->status, options, rup);
1110 	if (error)
1111 		return (error);
1112 	if (args->rusage != NULL)
1113 		error = copyout(&ru, args->rusage, sizeof(ru));
1114 
1115 	return (error);
1116 }
1117