compat.c 27.7 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084
/*
 *  linux/kernel/compat.c
 *
 *  Kernel compatibililty routines for e.g. 32 bit syscall support
 *  on 64 bit kernels.
 *
 *  Copyright (C) 2002-2003 Stephen Rothwell, IBM Corporation
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 */

#include <linux/linkage.h>
#include <linux/compat.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/signal.h>
#include <linux/sched.h>	/* for MAX_SCHEDULE_TIMEOUT */
#include <linux/syscalls.h>
#include <linux/unistd.h>
#include <linux/security.h>
#include <linux/timex.h>
#include <linux/migrate.h>
#include <linux/posix-timers.h>

#include <asm/uaccess.h>

int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
{
	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
			__get_user(ts->tv_sec, &cts->tv_sec) ||
			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
}

int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
{
	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
			__put_user(ts->tv_sec, &cts->tv_sec) ||
			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
}

static long compat_nanosleep_restart(struct restart_block *restart)
{
	unsigned long expire = restart->arg0, now = jiffies;
	struct compat_timespec __user *rmtp;

	/* Did it expire while we handled signals? */
	if (!time_after(expire, now))
		return 0;

	expire = schedule_timeout_interruptible(expire - now);
	if (expire == 0)
		return 0;

	rmtp = (struct compat_timespec __user *)restart->arg1;
	if (rmtp) {
		struct compat_timespec ct;
		struct timespec t;

		jiffies_to_timespec(expire, &t);
		ct.tv_sec = t.tv_sec;
		ct.tv_nsec = t.tv_nsec;
		if (copy_to_user(rmtp, &ct, sizeof(ct)))
			return -EFAULT;
	}
	/* The 'restart' block is already filled in */
	return -ERESTART_RESTARTBLOCK;
}

asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
		struct compat_timespec __user *rmtp)
{
	struct timespec t;
	struct restart_block *restart;
	unsigned long expire;

	if (get_compat_timespec(&t, rqtp))
		return -EFAULT;

	if ((t.tv_nsec >= 1000000000L) || (t.tv_nsec < 0) || (t.tv_sec < 0))
		return -EINVAL;

	expire = timespec_to_jiffies(&t) + (t.tv_sec || t.tv_nsec);
	expire = schedule_timeout_interruptible(expire);
	if (expire == 0)
		return 0;

	if (rmtp) {
		jiffies_to_timespec(expire, &t);
		if (put_compat_timespec(&t, rmtp))
			return -EFAULT;
	}
	restart = &current_thread_info()->restart_block;
	restart->fn = compat_nanosleep_restart;
	restart->arg0 = jiffies + expire;
	restart->arg1 = (unsigned long) rmtp;
	return -ERESTART_RESTARTBLOCK;
}

static inline long get_compat_itimerval(struct itimerval *o,
		struct compat_itimerval __user *i)
{
	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
}

static inline long put_compat_itimerval(struct compat_itimerval __user *o,
		struct itimerval *i)
{
	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
}

asmlinkage long compat_sys_getitimer(int which,
		struct compat_itimerval __user *it)
{
	struct itimerval kit;
	int error;

	error = do_getitimer(which, &kit);
	if (!error && put_compat_itimerval(it, &kit))
		error = -EFAULT;
	return error;
}

asmlinkage long compat_sys_setitimer(int which,
		struct compat_itimerval __user *in,
		struct compat_itimerval __user *out)
{
	struct itimerval kin, kout;
	int error;

	if (in) {
		if (get_compat_itimerval(&kin, in))
			return -EFAULT;
	} else
		memset(&kin, 0, sizeof(kin));

	error = do_setitimer(which, &kin, out ? &kout : NULL);
	if (error || !out)
		return error;
	if (put_compat_itimerval(out, &kout))
		return -EFAULT;
	return 0;
}

asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
{
	/*
	 *	In the SMP world we might just be unlucky and have one of
	 *	the times increment as we use it. Since the value is an
	 *	atomically safe type this is just fine. Conceptually its
	 *	as if the syscall took an instant longer to occur.
	 */
	if (tbuf) {
		struct compat_tms tmp;
		struct task_struct *tsk = current;
		struct task_struct *t;
		cputime_t utime, stime, cutime, cstime;

		read_lock(&tasklist_lock);
		utime = tsk->signal->utime;
		stime = tsk->signal->stime;
		t = tsk;
		do {
			utime = cputime_add(utime, t->utime);
			stime = cputime_add(stime, t->stime);
			t = next_thread(t);
		} while (t != tsk);

		/*
		 * While we have tasklist_lock read-locked, no dying thread
		 * can be updating current->signal->[us]time.  Instead,
		 * we got their counts included in the live thread loop.
		 * However, another thread can come in right now and
		 * do a wait call that updates current->signal->c[us]time.
		 * To make sure we always see that pair updated atomically,
		 * we take the siglock around fetching them.
		 */
		spin_lock_irq(&tsk->sighand->siglock);
		cutime = tsk->signal->cutime;
		cstime = tsk->signal->cstime;
		spin_unlock_irq(&tsk->sighand->siglock);
		read_unlock(&tasklist_lock);

		tmp.tms_utime = compat_jiffies_to_clock_t(cputime_to_jiffies(utime));
		tmp.tms_stime = compat_jiffies_to_clock_t(cputime_to_jiffies(stime));
		tmp.tms_cutime = compat_jiffies_to_clock_t(cputime_to_jiffies(cutime));
		tmp.tms_cstime = compat_jiffies_to_clock_t(cputime_to_jiffies(cstime));
		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
			return -EFAULT;
	}
	return compat_jiffies_to_clock_t(jiffies);
}

/*
 * Assumption: old_sigset_t and compat_old_sigset_t are both
 * types that can be passed to put_user()/get_user().
 */

asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
{
	old_sigset_t s;
	long ret;
	mm_segment_t old_fs = get_fs();

	set_fs(KERNEL_DS);
	ret = sys_sigpending((old_sigset_t __user *) &s);
	set_fs(old_fs);
	if (ret == 0)
		ret = put_user(s, set);
	return ret;
}

asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *set,
		compat_old_sigset_t __user *oset)
{
	old_sigset_t s;
	long ret;
	mm_segment_t old_fs;

	if (set && get_user(s, set))
		return -EFAULT;
	old_fs = get_fs();
	set_fs(KERNEL_DS);
	ret = sys_sigprocmask(how,
			      set ? (old_sigset_t __user *) &s : NULL,
			      oset ? (old_sigset_t __user *) &s : NULL);
	set_fs(old_fs);
	if (ret == 0)
		if (oset)
			ret = put_user(s, oset);
	return ret;
}

asmlinkage long compat_sys_setrlimit(unsigned int resource,
		struct compat_rlimit __user *rlim)
{
	struct rlimit r;
	int ret;
	mm_segment_t old_fs = get_fs ();

	if (resource >= RLIM_NLIMITS) 
		return -EINVAL;	

	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
	    __get_user(r.rlim_max, &rlim->rlim_max))
		return -EFAULT;

	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
		r.rlim_cur = RLIM_INFINITY;
	if (r.rlim_max == COMPAT_RLIM_INFINITY)
		r.rlim_max = RLIM_INFINITY;
	set_fs(KERNEL_DS);
	ret = sys_setrlimit(resource, (struct rlimit __user *) &r);
	set_fs(old_fs);
	return ret;
}

#ifdef COMPAT_RLIM_OLD_INFINITY

asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
		struct compat_rlimit __user *rlim)
{
	struct rlimit r;
	int ret;
	mm_segment_t old_fs = get_fs();

	set_fs(KERNEL_DS);
	ret = sys_old_getrlimit(resource, &r);
	set_fs(old_fs);

	if (!ret) {
		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
			r.rlim_cur = COMPAT_RLIM_INFINITY;
		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
			r.rlim_max = COMPAT_RLIM_INFINITY;

		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
		    __put_user(r.rlim_max, &rlim->rlim_max))
			return -EFAULT;
	}
	return ret;
}

#endif

asmlinkage long compat_sys_getrlimit (unsigned int resource,
		struct compat_rlimit __user *rlim)
{
	struct rlimit r;
	int ret;
	mm_segment_t old_fs = get_fs();

	set_fs(KERNEL_DS);
	ret = sys_getrlimit(resource, (struct rlimit __user *) &r);
	set_fs(old_fs);
	if (!ret) {
		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
			r.rlim_cur = COMPAT_RLIM_INFINITY;
		if (r.rlim_max > COMPAT_RLIM_INFINITY)
			r.rlim_max = COMPAT_RLIM_INFINITY;

		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
		    __put_user(r.rlim_max, &rlim->rlim_max))
			return -EFAULT;
	}
	return ret;
}

int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
{
	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
		return -EFAULT;
	return 0;
}

asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
{
	struct rusage r;
	int ret;
	mm_segment_t old_fs = get_fs();

	set_fs(KERNEL_DS);
	ret = sys_getrusage(who, (struct rusage __user *) &r);
	set_fs(old_fs);

	if (ret)
		return ret;

	if (put_compat_rusage(&r, ru))
		return -EFAULT;

	return 0;
}

asmlinkage long
compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
	struct compat_rusage __user *ru)
{
	if (!ru) {
		return sys_wait4(pid, stat_addr, options, NULL);
	} else {
		struct rusage r;
		int ret;
		unsigned int status;
		mm_segment_t old_fs = get_fs();

		set_fs (KERNEL_DS);
		ret = sys_wait4(pid,
				(stat_addr ?
				 (unsigned int __user *) &status : NULL),
				options, (struct rusage __user *) &r);
		set_fs (old_fs);

		if (ret > 0) {
			if (put_compat_rusage(&r, ru))
				return -EFAULT;
			if (stat_addr && put_user(status, stat_addr))
				return -EFAULT;
		}
		return ret;
	}
}

asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
		struct compat_siginfo __user *uinfo, int options,
		struct compat_rusage __user *uru)
{
	siginfo_t info;
	struct rusage ru;
	long ret;
	mm_segment_t old_fs = get_fs();

	memset(&info, 0, sizeof(info));

	set_fs(KERNEL_DS);
	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
			 uru ? (struct rusage __user *)&ru : NULL);
	set_fs(old_fs);

	if ((ret < 0) || (info.si_signo == 0))
		return ret;

	if (uru) {
		ret = put_compat_rusage(&ru, uru);
		if (ret)
			return ret;
	}

	BUG_ON(info.si_code & __SI_MASK);
	info.si_code |= __SI_CHLD;
	return copy_siginfo_to_user32(uinfo, &info);
}

static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
				    unsigned len, cpumask_t *new_mask)
{
	unsigned long *k;

	if (len < sizeof(cpumask_t))
		memset(new_mask, 0, sizeof(cpumask_t));
	else if (len > sizeof(cpumask_t))
		len = sizeof(cpumask_t);

	k = cpus_addr(*new_mask);
	return compat_get_bitmap(k, user_mask_ptr, len * 8);
}

asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
					     unsigned int len,
					     compat_ulong_t __user *user_mask_ptr)
{
	cpumask_t new_mask;
	int retval;

	retval = compat_get_user_cpu_mask(user_mask_ptr, len, &new_mask);
	if (retval)
		return retval;

	return sched_setaffinity(pid, new_mask);
}

asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
					     compat_ulong_t __user *user_mask_ptr)
{
	int ret;
	cpumask_t mask;
	unsigned long *k;
	unsigned int min_length = sizeof(cpumask_t);

	if (NR_CPUS <= BITS_PER_COMPAT_LONG)
		min_length = sizeof(compat_ulong_t);

	if (len < min_length)
		return -EINVAL;

	ret = sched_getaffinity(pid, &mask);
	if (ret < 0)
		return ret;

	k = cpus_addr(mask);
	ret = compat_put_bitmap(user_mask_ptr, k, min_length * 8);
	if (ret)
		return ret;

	return min_length;
}

int get_compat_itimerspec(struct itimerspec *dst,
			  const struct compat_itimerspec __user *src)
{ 
	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
	    get_compat_timespec(&dst->it_value, &src->it_value))
		return -EFAULT;
	return 0;
} 

int put_compat_itimerspec(struct compat_itimerspec __user *dst,
			  const struct itimerspec *src)
{ 
	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
	    put_compat_timespec(&src->it_value, &dst->it_value))
		return -EFAULT;
	return 0;
} 

long compat_sys_timer_create(clockid_t which_clock,
			struct compat_sigevent __user *timer_event_spec,
			timer_t __user *created_timer_id)
{
	struct sigevent __user *event = NULL;

	if (timer_event_spec) {
		struct sigevent kevent;

		event = compat_alloc_user_space(sizeof(*event));
		if (get_compat_sigevent(&kevent, timer_event_spec) ||
		    copy_to_user(event, &kevent, sizeof(*event)))
			return -EFAULT;
	}

	return sys_timer_create(which_clock, event, created_timer_id);
}

long compat_sys_timer_settime(timer_t timer_id, int flags,
			  struct compat_itimerspec __user *new, 
			  struct compat_itimerspec __user *old)
{ 
	long err;
	mm_segment_t oldfs;
	struct itimerspec newts, oldts;

	if (!new)
		return -EINVAL;
	if (get_compat_itimerspec(&newts, new))
		return -EFAULT;	
	oldfs = get_fs();
	set_fs(KERNEL_DS);
	err = sys_timer_settime(timer_id, flags,
				(struct itimerspec __user *) &newts,
				(struct itimerspec __user *) &oldts);
	set_fs(oldfs); 
	if (!err && old && put_compat_itimerspec(old, &oldts))
		return -EFAULT;
	return err;
} 

long compat_sys_timer_gettime(timer_t timer_id,
		struct compat_itimerspec __user *setting)
{ 
	long err;
	mm_segment_t oldfs;
	struct itimerspec ts; 

	oldfs = get_fs();
	set_fs(KERNEL_DS);
	err = sys_timer_gettime(timer_id,
				(struct itimerspec __user *) &ts); 
	set_fs(oldfs); 
	if (!err && put_compat_itimerspec(setting, &ts))
		return -EFAULT;
	return err;
} 

long compat_sys_clock_settime(clockid_t which_clock,
		struct compat_timespec __user *tp)
{
	long err;
	mm_segment_t oldfs;
	struct timespec ts; 

	if (get_compat_timespec(&ts, tp))
		return -EFAULT; 
	oldfs = get_fs();
	set_fs(KERNEL_DS);	
	err = sys_clock_settime(which_clock,
				(struct timespec __user *) &ts);
	set_fs(oldfs);
	return err;
} 

long compat_sys_clock_gettime(clockid_t which_clock,
		struct compat_timespec __user *tp)
{
	long err;
	mm_segment_t oldfs;
	struct timespec ts; 

	oldfs = get_fs();
	set_fs(KERNEL_DS);
	err = sys_clock_gettime(which_clock,
				(struct timespec __user *) &ts);
	set_fs(oldfs);
	if (!err && put_compat_timespec(&ts, tp))
		return -EFAULT; 
	return err;
} 

long compat_sys_clock_getres(clockid_t which_clock,
		struct compat_timespec __user *tp)
{
	long err;
	mm_segment_t oldfs;
	struct timespec ts; 

	oldfs = get_fs();
	set_fs(KERNEL_DS);
	err = sys_clock_getres(which_clock,
			       (struct timespec __user *) &ts);
	set_fs(oldfs);
	if (!err && tp && put_compat_timespec(&ts, tp))
		return -EFAULT; 
	return err;
} 

static long compat_clock_nanosleep_restart(struct restart_block *restart)
{
	long err;
	mm_segment_t oldfs;
	struct timespec tu;
	struct compat_timespec *rmtp = (struct compat_timespec *)(restart->arg1);

	restart->arg1 = (unsigned long) &tu;
	oldfs = get_fs();
	set_fs(KERNEL_DS);
	err = clock_nanosleep_restart(restart);
	set_fs(oldfs);

	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
	    put_compat_timespec(&tu, rmtp))
		return -EFAULT;

	if (err == -ERESTART_RESTARTBLOCK) {
		restart->fn = compat_clock_nanosleep_restart;
		restart->arg1 = (unsigned long) rmtp;
	}
	return err;
}

long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
			    struct compat_timespec __user *rqtp,
			    struct compat_timespec __user *rmtp)
{
	long err;
	mm_segment_t oldfs;
	struct timespec in, out; 
	struct restart_block *restart;

	if (get_compat_timespec(&in, rqtp)) 
		return -EFAULT;

	oldfs = get_fs();
	set_fs(KERNEL_DS);
	err = sys_clock_nanosleep(which_clock, flags,
				  (struct timespec __user *) &in,
				  (struct timespec __user *) &out);
	set_fs(oldfs);

	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
	    put_compat_timespec(&out, rmtp))
		return -EFAULT;

	if (err == -ERESTART_RESTARTBLOCK) {
		restart = &current_thread_info()->restart_block;
		restart->fn = compat_clock_nanosleep_restart;
		restart->arg1 = (unsigned long) rmtp;
	}
	return err;	
} 

/*
 * We currently only need the following fields from the sigevent
 * structure: sigev_value, sigev_signo, sig_notify and (sometimes
 * sigev_notify_thread_id).  The others are handled in user mode.
 * We also assume that copying sigev_value.sival_int is sufficient
 * to keep all the bits of sigev_value.sival_ptr intact.
 */
int get_compat_sigevent(struct sigevent *event,
		const struct compat_sigevent __user *u_event)
{
	memset(event, 0, sizeof(*event));
	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
		__get_user(event->sigev_value.sival_int,
			&u_event->sigev_value.sival_int) ||
		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
		__get_user(event->sigev_notify_thread_id,
			&u_event->sigev_notify_thread_id))
		? -EFAULT : 0;
}

long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
		       unsigned long bitmap_size)
{
	int i, j;
	unsigned long m;
	compat_ulong_t um;
	unsigned long nr_compat_longs;

	/* align bitmap up to nearest compat_long_t boundary */
	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);

	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
		return -EFAULT;

	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);

	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
		m = 0;

		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
			/*
			 * We dont want to read past the end of the userspace
			 * bitmap. We must however ensure the end of the
			 * kernel bitmap is zeroed.
			 */
			if (nr_compat_longs-- > 0) {
				if (__get_user(um, umask))
					return -EFAULT;
			} else {
				um = 0;
			}

			umask++;
			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
		}
		*mask++ = m;
	}

	return 0;
}

long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
		       unsigned long bitmap_size)
{
	int i, j;
	unsigned long m;
	compat_ulong_t um;
	unsigned long nr_compat_longs;

	/* align bitmap up to nearest compat_long_t boundary */
	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);

	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
		return -EFAULT;

	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);

	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
		m = *mask++;

		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
			um = m;

			/*
			 * We dont want to write past the end of the userspace
			 * bitmap.
			 */
			if (nr_compat_longs-- > 0) {
				if (__put_user(um, umask))
					return -EFAULT;
			}

			umask++;
			m >>= 4*sizeof(um);
			m >>= 4*sizeof(um);
		}
	}

	return 0;
}

void
sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
{
	switch (_NSIG_WORDS) {
	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
	}
}

asmlinkage long
compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
		struct compat_siginfo __user *uinfo,
		struct compat_timespec __user *uts, compat_size_t sigsetsize)
{
	compat_sigset_t s32;
	sigset_t s;
	int sig;
	struct timespec t;
	siginfo_t info;
	long ret, timeout = 0;

	if (sigsetsize != sizeof(sigset_t))
		return -EINVAL;

	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
		return -EFAULT;
	sigset_from_compat(&s, &s32);
	sigdelsetmask(&s,sigmask(SIGKILL)|sigmask(SIGSTOP));
	signotset(&s);

	if (uts) {
		if (get_compat_timespec (&t, uts))
			return -EFAULT;
		if (t.tv_nsec >= 1000000000L || t.tv_nsec < 0
				|| t.tv_sec < 0)
			return -EINVAL;
	}

	spin_lock_irq(&current->sighand->siglock);
	sig = dequeue_signal(current, &s, &info);
	if (!sig) {
		timeout = MAX_SCHEDULE_TIMEOUT;
		if (uts)
			timeout = timespec_to_jiffies(&t)
				+(t.tv_sec || t.tv_nsec);
		if (timeout) {
			current->real_blocked = current->blocked;
			sigandsets(&current->blocked, &current->blocked, &s);

			recalc_sigpending();
			spin_unlock_irq(&current->sighand->siglock);

			timeout = schedule_timeout_interruptible(timeout);

			spin_lock_irq(&current->sighand->siglock);
			sig = dequeue_signal(current, &s, &info);
			current->blocked = current->real_blocked;
			siginitset(&current->real_blocked, 0);
			recalc_sigpending();
		}
	}
	spin_unlock_irq(&current->sighand->siglock);

	if (sig) {
		ret = sig;
		if (uinfo) {
			if (copy_siginfo_to_user32(uinfo, &info))
				ret = -EFAULT;
		}
	}else {
		ret = timeout?-EINTR:-EAGAIN;
	}
	return ret;

}

#ifdef __ARCH_WANT_COMPAT_SYS_TIME

/* compat_time_t is a 32 bit "long" and needs to get converted. */

asmlinkage long compat_sys_time(compat_time_t __user * tloc)
{
	compat_time_t i;
	struct timeval tv;

	do_gettimeofday(&tv);
	i = tv.tv_sec;

	if (tloc) {
		if (put_user(i,tloc))
			i = -EFAULT;
	}
	return i;
}

asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
{
	struct timespec tv;
	int err;

	if (get_user(tv.tv_sec, tptr))
		return -EFAULT;

	tv.tv_nsec = 0;

	err = security_settime(&tv, NULL);
	if (err)
		return err;

	do_settimeofday(&tv);
	return 0;
}

#endif /* __ARCH_WANT_COMPAT_SYS_TIME */

#ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
{
	sigset_t newset;
	compat_sigset_t newset32;

	/* XXX: Don't preclude handling different sized sigset_t's.  */
	if (sigsetsize != sizeof(sigset_t))
		return -EINVAL;

	if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
		return -EFAULT;
	sigset_from_compat(&newset, &newset32);
	sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));

	spin_lock_irq(&current->sighand->siglock);
	current->saved_sigmask = current->blocked;
	current->blocked = newset;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	current->state = TASK_INTERRUPTIBLE;
	schedule();
	set_thread_flag(TIF_RESTORE_SIGMASK);
	return -ERESTARTNOHAND;
}
#endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */

asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
{
	struct timex txc;
	int ret;

	memset(&txc, 0, sizeof(struct timex));

	if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
			__get_user(txc.modes, &utp->modes) ||
			__get_user(txc.offset, &utp->offset) ||
			__get_user(txc.freq, &utp->freq) ||
			__get_user(txc.maxerror, &utp->maxerror) ||
			__get_user(txc.esterror, &utp->esterror) ||
			__get_user(txc.status, &utp->status) ||
			__get_user(txc.constant, &utp->constant) ||
			__get_user(txc.precision, &utp->precision) ||
			__get_user(txc.tolerance, &utp->tolerance) ||
			__get_user(txc.time.tv_sec, &utp->time.tv_sec) ||
			__get_user(txc.time.tv_usec, &utp->time.tv_usec) ||
			__get_user(txc.tick, &utp->tick) ||
			__get_user(txc.ppsfreq, &utp->ppsfreq) ||
			__get_user(txc.jitter, &utp->jitter) ||
			__get_user(txc.shift, &utp->shift) ||
			__get_user(txc.stabil, &utp->stabil) ||
			__get_user(txc.jitcnt, &utp->jitcnt) ||
			__get_user(txc.calcnt, &utp->calcnt) ||
			__get_user(txc.errcnt, &utp->errcnt) ||
			__get_user(txc.stbcnt, &utp->stbcnt))
		return -EFAULT;

	ret = do_adjtimex(&txc);

	if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
			__put_user(txc.modes, &utp->modes) ||
			__put_user(txc.offset, &utp->offset) ||
			__put_user(txc.freq, &utp->freq) ||
			__put_user(txc.maxerror, &utp->maxerror) ||
			__put_user(txc.esterror, &utp->esterror) ||
			__put_user(txc.status, &utp->status) ||
			__put_user(txc.constant, &utp->constant) ||
			__put_user(txc.precision, &utp->precision) ||
			__put_user(txc.tolerance, &utp->tolerance) ||
			__put_user(txc.time.tv_sec, &utp->time.tv_sec) ||
			__put_user(txc.time.tv_usec, &utp->time.tv_usec) ||
			__put_user(txc.tick, &utp->tick) ||
			__put_user(txc.ppsfreq, &utp->ppsfreq) ||
			__put_user(txc.jitter, &utp->jitter) ||
			__put_user(txc.shift, &utp->shift) ||
			__put_user(txc.stabil, &utp->stabil) ||
			__put_user(txc.jitcnt, &utp->jitcnt) ||
			__put_user(txc.calcnt, &utp->calcnt) ||
			__put_user(txc.errcnt, &utp->errcnt) ||
			__put_user(txc.stbcnt, &utp->stbcnt))
		ret = -EFAULT;

	return ret;
}

#ifdef CONFIG_NUMA
asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
		compat_uptr_t __user *pages32,
		const int __user *nodes,
		int __user *status,
		int flags)
{
	const void __user * __user *pages;
	int i;

	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
	for (i = 0; i < nr_pages; i++) {
		compat_uptr_t p;

		if (get_user(p, pages32 + i) ||
			put_user(compat_ptr(p), pages + i))
			return -EFAULT;
	}
	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
}

asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
			compat_ulong_t maxnode,
			const compat_ulong_t __user *old_nodes,
			const compat_ulong_t __user *new_nodes)
{
	unsigned long __user *old = NULL;
	unsigned long __user *new = NULL;
	nodemask_t tmp_mask;
	unsigned long nr_bits;
	unsigned long size;

	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
	if (old_nodes) {
		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
			return -EFAULT;
		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
		if (new_nodes)
			new = old + size / sizeof(unsigned long);
		if (copy_to_user(old, nodes_addr(tmp_mask), size))
			return -EFAULT;
	}
	if (new_nodes) {
		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
			return -EFAULT;
		if (new == NULL)
			new = compat_alloc_user_space(size);
		if (copy_to_user(new, nodes_addr(tmp_mask), size))
			return -EFAULT;
	}
	return sys_migrate_pages(pid, nr_bits + 1, old, new);
}
#endif

struct compat_sysinfo {
	s32 uptime;
	u32 loads[3];
	u32 totalram;
	u32 freeram;
	u32 sharedram;
	u32 bufferram;
	u32 totalswap;
	u32 freeswap;
	u16 procs;
	u16 pad;
	u32 totalhigh;
	u32 freehigh;
	u32 mem_unit;
	char _f[20-2*sizeof(u32)-sizeof(int)];
};

asmlinkage long
compat_sys_sysinfo(struct compat_sysinfo __user *info)
{
	struct sysinfo s;

	do_sysinfo(&s);

	/* Check to see if any memory value is too large for 32-bit and scale
	 *  down if needed
	 */
	if ((s.totalram >> 32) || (s.totalswap >> 32)) {
		int bitcount = 0;

		while (s.mem_unit < PAGE_SIZE) {
			s.mem_unit <<= 1;
			bitcount++;
		}

		s.totalram >>= bitcount;
		s.freeram >>= bitcount;
		s.sharedram >>= bitcount;
		s.bufferram >>= bitcount;
		s.totalswap >>= bitcount;
		s.freeswap >>= bitcount;
		s.totalhigh >>= bitcount;
		s.freehigh >>= bitcount;
	}

	if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
	    __put_user (s.uptime, &info->uptime) ||
	    __put_user (s.loads[0], &info->loads[0]) ||
	    __put_user (s.loads[1], &info->loads[1]) ||
	    __put_user (s.loads[2], &info->loads[2]) ||
	    __put_user (s.totalram, &info->totalram) ||
	    __put_user (s.freeram, &info->freeram) ||
	    __put_user (s.sharedram, &info->sharedram) ||
	    __put_user (s.bufferram, &info->bufferram) ||
	    __put_user (s.totalswap, &info->totalswap) ||
	    __put_user (s.freeswap, &info->freeswap) ||
	    __put_user (s.procs, &info->procs) ||
	    __put_user (s.totalhigh, &info->totalhigh) ||
	    __put_user (s.freehigh, &info->freehigh) ||
	    __put_user (s.mem_unit, &info->mem_unit))
		return -EFAULT;

	return 0;
}