Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6

[mirror_ubuntu-jammy-kernel.git] / arch / x86_64 / ia32 / sys_ia32.c

/*
 * sys_ia32.c: Conversion between 32bit and 64bit native syscalls. Based on
 *             sys_sparc32 
 *
 * Copyright (C) 2000           VA Linux Co
 * Copyright (C) 2000           Don Dugger <n0ano@valinux.com>
 * Copyright (C) 1999           Arun Sharma <arun.sharma@intel.com>
 * Copyright (C) 1997,1998      Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 * Copyright (C) 1997           David S. Miller (davem@caip.rutgers.edu)
 * Copyright (C) 2000           Hewlett-Packard Co.
 * Copyright (C) 2000           David Mosberger-Tang <davidm@hpl.hp.com>
 * Copyright (C) 2000,2001,2002 Andi Kleen, SuSE Labs (x86-64 port) 
 *
 * These routines maintain argument size conversion between 32bit and 64bit
 * environment. In 2.5 most of this should be moved to a generic directory. 
 *
 * This file assumes that there is a hole at the end of user address space.
 * 
 * Some of the functions are LE specific currently. These are hopefully all marked.
 * This should be fixed.
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h> 
#include <linux/file.h> 
#include <linux/signal.h>
#include <linux/syscalls.h>
#include <linux/resource.h>
#include <linux/times.h>
#include <linux/utsname.h>
#include <linux/timex.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/mm.h>
#include <linux/shm.h>
#include <linux/slab.h>
#include <linux/uio.h>
#include <linux/nfs_fs.h>
#include <linux/quota.h>
#include <linux/module.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/cache.h>
#include <linux/nfsd/xdr.h>
#include <linux/nfsd/syscall.h>
#include <linux/poll.h>
#include <linux/personality.h>
#include <linux/stat.h>
#include <linux/ipc.h>
#include <linux/rwsem.h>
#include <linux/binfmts.h>
#include <linux/init.h>
#include <linux/aio_abi.h>
#include <linux/aio.h>
#include <linux/compat.h>
#include <linux/vfs.h>
#include <linux/ptrace.h>
#include <linux/highuid.h>
#include <linux/vmalloc.h>
#include <linux/fsnotify.h>
#include <asm/mman.h>
#include <asm/types.h>
#include <asm/uaccess.h>
#include <asm/semaphore.h>
#include <asm/atomic.h>
#include <asm/ldt.h>

#include <net/scm.h>
#include <net/sock.h>
#include <asm/ia32.h>

#define AA(__x)         ((unsigned long)(__x))

int cp_compat_stat(struct kstat *kbuf, struct compat_stat __user *ubuf)
{
        typeof(ubuf->st_uid) uid = 0;
        typeof(ubuf->st_gid) gid = 0;
        SET_UID(uid, kbuf->uid);
        SET_GID(gid, kbuf->gid);
        if (!old_valid_dev(kbuf->dev) || !old_valid_dev(kbuf->rdev))
                return -EOVERFLOW;
        if (kbuf->size >= 0x7fffffff)
                return -EOVERFLOW;
        if (!access_ok(VERIFY_WRITE, ubuf, sizeof(struct compat_stat)) ||
            __put_user (old_encode_dev(kbuf->dev), &ubuf->st_dev) ||
            __put_user (kbuf->ino, &ubuf->st_ino) ||
            __put_user (kbuf->mode, &ubuf->st_mode) ||
            __put_user (kbuf->nlink, &ubuf->st_nlink) ||
            __put_user (uid, &ubuf->st_uid) ||
            __put_user (gid, &ubuf->st_gid) ||
            __put_user (old_encode_dev(kbuf->rdev), &ubuf->st_rdev) ||
            __put_user (kbuf->size, &ubuf->st_size) ||
            __put_user (kbuf->atime.tv_sec, &ubuf->st_atime) ||
            __put_user (kbuf->atime.tv_nsec, &ubuf->st_atime_nsec) ||
            __put_user (kbuf->mtime.tv_sec, &ubuf->st_mtime) ||
            __put_user (kbuf->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
            __put_user (kbuf->ctime.tv_sec, &ubuf->st_ctime) ||
            __put_user (kbuf->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
            __put_user (kbuf->blksize, &ubuf->st_blksize) ||
            __put_user (kbuf->blocks, &ubuf->st_blocks))
                return -EFAULT;
        return 0;
}

asmlinkage long
sys32_truncate64(char __user * filename, unsigned long offset_low, unsigned long offset_high)
{
       return sys_truncate(filename, ((loff_t) offset_high << 32) | offset_low);
}

asmlinkage long
sys32_ftruncate64(unsigned int fd, unsigned long offset_low, unsigned long offset_high)
{
       return sys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low);
}

/* Another set for IA32/LFS -- x86_64 struct stat is different due to 
   support for 64bit inode numbers. */

static int
cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
{
        typeof(ubuf->st_uid) uid = 0;
        typeof(ubuf->st_gid) gid = 0;
        SET_UID(uid, stat->uid);
        SET_GID(gid, stat->gid);
        if (!access_ok(VERIFY_WRITE, ubuf, sizeof(struct stat64)) ||
            __put_user(huge_encode_dev(stat->dev), &ubuf->st_dev) ||
            __put_user (stat->ino, &ubuf->__st_ino) ||
            __put_user (stat->ino, &ubuf->st_ino) ||
            __put_user (stat->mode, &ubuf->st_mode) ||
            __put_user (stat->nlink, &ubuf->st_nlink) ||
            __put_user (uid, &ubuf->st_uid) ||
            __put_user (gid, &ubuf->st_gid) ||
            __put_user (huge_encode_dev(stat->rdev), &ubuf->st_rdev) ||
            __put_user (stat->size, &ubuf->st_size) ||
            __put_user (stat->atime.tv_sec, &ubuf->st_atime) ||
            __put_user (stat->atime.tv_nsec, &ubuf->st_atime_nsec) ||
            __put_user (stat->mtime.tv_sec, &ubuf->st_mtime) ||
            __put_user (stat->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
            __put_user (stat->ctime.tv_sec, &ubuf->st_ctime) ||
            __put_user (stat->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
            __put_user (stat->blksize, &ubuf->st_blksize) ||
            __put_user (stat->blocks, &ubuf->st_blocks))
                return -EFAULT;
        return 0;
}

asmlinkage long
sys32_stat64(char __user * filename, struct stat64 __user *statbuf)
{
        struct kstat stat;
        int ret = vfs_stat(filename, &stat);
        if (!ret)
                ret = cp_stat64(statbuf, &stat);
        return ret;
}

asmlinkage long
sys32_lstat64(char __user * filename, struct stat64 __user *statbuf)
{
        struct kstat stat;
        int ret = vfs_lstat(filename, &stat);
        if (!ret)
                ret = cp_stat64(statbuf, &stat);
        return ret;
}

asmlinkage long
sys32_fstat64(unsigned int fd, struct stat64 __user *statbuf)
{
        struct kstat stat;
        int ret = vfs_fstat(fd, &stat);
        if (!ret)
                ret = cp_stat64(statbuf, &stat);
        return ret;
}

asmlinkage long
sys32_fstatat(unsigned int dfd, char __user *filename,
              struct stat64 __user* statbuf, int flag)
{
        struct kstat stat;
        int error = -EINVAL;

        if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
                goto out;

        if (flag & AT_SYMLINK_NOFOLLOW)
                error = vfs_lstat_fd(dfd, filename, &stat);
        else
                error = vfs_stat_fd(dfd, filename, &stat);

        if (!error)
                error = cp_stat64(statbuf, &stat);

out:
        return error;
}

/*
 * Linux/i386 didn't use to be able to handle more than
 * 4 system call parameters, so these system calls used a memory
 * block for parameter passing..
 */

struct mmap_arg_struct {
        unsigned int addr;
        unsigned int len;
        unsigned int prot;
        unsigned int flags;
        unsigned int fd;
        unsigned int offset;
};

asmlinkage long
sys32_mmap(struct mmap_arg_struct __user *arg)
{
        struct mmap_arg_struct a;
        struct file *file = NULL;
        unsigned long retval;
        struct mm_struct *mm ;

        if (copy_from_user(&a, arg, sizeof(a)))
                return -EFAULT;

        if (a.offset & ~PAGE_MASK)
                return -EINVAL; 

        if (!(a.flags & MAP_ANONYMOUS)) {
                file = fget(a.fd);
                if (!file)
                        return -EBADF;
        }
        
        mm = current->mm; 
        down_write(&mm->mmap_sem); 
        retval = do_mmap_pgoff(file, a.addr, a.len, a.prot, a.flags, a.offset>>PAGE_SHIFT);
        if (file)
                fput(file);

        up_write(&mm->mmap_sem); 

        return retval;
}

asmlinkage long 
sys32_mprotect(unsigned long start, size_t len, unsigned long prot)
{
        return sys_mprotect(start,len,prot); 
}

asmlinkage long
sys32_pipe(int __user *fd)
{
        int retval;
        int fds[2];

        retval = do_pipe(fds);
        if (retval)
                goto out;
        if (copy_to_user(fd, fds, sizeof(fds)))
                retval = -EFAULT;
  out:
        return retval;
}

asmlinkage long
sys32_rt_sigaction(int sig, struct sigaction32 __user *act,
                   struct sigaction32 __user *oact,  unsigned int sigsetsize)
{
        struct k_sigaction new_ka, old_ka;
        int ret;
        compat_sigset_t set32;

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

        if (act) {
                compat_uptr_t handler, restorer;

                if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
                    __get_user(handler, &act->sa_handler) ||
                    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
                    __get_user(restorer, &act->sa_restorer)||
                    __copy_from_user(&set32, &act->sa_mask, sizeof(compat_sigset_t)))
                        return -EFAULT;
                new_ka.sa.sa_handler = compat_ptr(handler);
                new_ka.sa.sa_restorer = compat_ptr(restorer);
                /* FIXME: here we rely on _COMPAT_NSIG_WORS to be >= than _NSIG_WORDS << 1 */
                switch (_NSIG_WORDS) {
                case 4: new_ka.sa.sa_mask.sig[3] = set32.sig[6]
                                | (((long)set32.sig[7]) << 32);
                case 3: new_ka.sa.sa_mask.sig[2] = set32.sig[4]
                                | (((long)set32.sig[5]) << 32);
                case 2: new_ka.sa.sa_mask.sig[1] = set32.sig[2]
                                | (((long)set32.sig[3]) << 32);
                case 1: new_ka.sa.sa_mask.sig[0] = set32.sig[0]
                                | (((long)set32.sig[1]) << 32);
                }
        }

        ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

        if (!ret && oact) {
                /* FIXME: here we rely on _COMPAT_NSIG_WORS to be >= than _NSIG_WORDS << 1 */
                switch (_NSIG_WORDS) {
                case 4:
                        set32.sig[7] = (old_ka.sa.sa_mask.sig[3] >> 32);
                        set32.sig[6] = old_ka.sa.sa_mask.sig[3];
                case 3:
                        set32.sig[5] = (old_ka.sa.sa_mask.sig[2] >> 32);
                        set32.sig[4] = old_ka.sa.sa_mask.sig[2];
                case 2:
                        set32.sig[3] = (old_ka.sa.sa_mask.sig[1] >> 32);
                        set32.sig[2] = old_ka.sa.sa_mask.sig[1];
                case 1:
                        set32.sig[1] = (old_ka.sa.sa_mask.sig[0] >> 32);
                        set32.sig[0] = old_ka.sa.sa_mask.sig[0];
                }
                if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
                    __put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler) ||
                    __put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer) ||
                    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
                    __copy_to_user(&oact->sa_mask, &set32, sizeof(compat_sigset_t)))
                        return -EFAULT;
        }

        return ret;
}

asmlinkage long
sys32_sigaction (int sig, struct old_sigaction32 __user *act, struct old_sigaction32 __user *oact)
{
        struct k_sigaction new_ka, old_ka;
        int ret;

        if (act) {
                compat_old_sigset_t mask;
                compat_uptr_t handler, restorer;

                if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
                    __get_user(handler, &act->sa_handler) ||
                    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
                    __get_user(restorer, &act->sa_restorer) ||
                    __get_user(mask, &act->sa_mask))
                        return -EFAULT;

                new_ka.sa.sa_handler = compat_ptr(handler);
                new_ka.sa.sa_restorer = compat_ptr(restorer);

                siginitset(&new_ka.sa.sa_mask, mask);
        }

        ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);

        if (!ret && oact) {
                if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
                    __put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler) ||
                    __put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer) ||
                    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
                    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
                        return -EFAULT;
        }

        return ret;
}

asmlinkage long
sys32_rt_sigprocmask(int how, compat_sigset_t __user *set,
                        compat_sigset_t __user *oset, unsigned int sigsetsize)
{
        sigset_t s;
        compat_sigset_t s32;
        int ret;
        mm_segment_t old_fs = get_fs();
        
        if (set) {
                if (copy_from_user (&s32, set, sizeof(compat_sigset_t)))
                        return -EFAULT;
                switch (_NSIG_WORDS) {
                case 4: s.sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
                case 3: s.sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
                case 2: s.sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
                case 1: s.sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
                }
        }
        set_fs (KERNEL_DS);
        ret = sys_rt_sigprocmask(how, set ? &s : NULL, oset ? &s : NULL,
                                 sigsetsize); 
        set_fs (old_fs);
        if (ret) return ret;
        if (oset) {
                switch (_NSIG_WORDS) {
                case 4: s32.sig[7] = (s.sig[3] >> 32); s32.sig[6] = s.sig[3];
                case 3: s32.sig[5] = (s.sig[2] >> 32); s32.sig[4] = s.sig[2];
                case 2: s32.sig[3] = (s.sig[1] >> 32); s32.sig[2] = s.sig[1];
                case 1: s32.sig[1] = (s.sig[0] >> 32); s32.sig[0] = s.sig[0];
                }
                if (copy_to_user (oset, &s32, sizeof(compat_sigset_t)))
                        return -EFAULT;
        }
        return 0;
}

static inline long
get_tv32(struct timeval *o, struct compat_timeval __user *i)
{
        int err = -EFAULT; 
        if (access_ok(VERIFY_READ, i, sizeof(*i))) { 
                err = __get_user(o->tv_sec, &i->tv_sec);
                err |= __get_user(o->tv_usec, &i->tv_usec);
        }
        return err; 
}

static inline long
put_tv32(struct compat_timeval __user *o, struct timeval *i)
{
        int err = -EFAULT;
        if (access_ok(VERIFY_WRITE, o, sizeof(*o))) { 
                err = __put_user(i->tv_sec, &o->tv_sec);
                err |= __put_user(i->tv_usec, &o->tv_usec);
        } 
        return err; 
}

extern unsigned int alarm_setitimer(unsigned int seconds);

asmlinkage long
sys32_alarm(unsigned int seconds)
{
        return alarm_setitimer(seconds);
}

/* Translations due to time_t size differences.  Which affects all
   sorts of things, like timeval and itimerval.  */

extern struct timezone sys_tz;

asmlinkage long
sys32_gettimeofday(struct compat_timeval __user *tv, struct timezone __user *tz)
{
        if (tv) {
                struct timeval ktv;
                do_gettimeofday(&ktv);
                if (put_tv32(tv, &ktv))
                        return -EFAULT;
        }
        if (tz) {
                if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
                        return -EFAULT;
        }
        return 0;
}

asmlinkage long
sys32_settimeofday(struct compat_timeval __user *tv, struct timezone __user *tz)
{
        struct timeval ktv;
        struct timespec kts;
        struct timezone ktz;

        if (tv) {
                if (get_tv32(&ktv, tv))
                        return -EFAULT;
                kts.tv_sec = ktv.tv_sec;
                kts.tv_nsec = ktv.tv_usec * NSEC_PER_USEC;
        }
        if (tz) {
                if (copy_from_user(&ktz, tz, sizeof(ktz)))
                        return -EFAULT;
        }

        return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
}

struct sel_arg_struct {
        unsigned int n;
        unsigned int inp;
        unsigned int outp;
        unsigned int exp;
        unsigned int tvp;
};

asmlinkage long
sys32_old_select(struct sel_arg_struct __user *arg)
{
        struct sel_arg_struct a;

        if (copy_from_user(&a, arg, sizeof(a)))
                return -EFAULT;
        return compat_sys_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp),
                                 compat_ptr(a.exp), compat_ptr(a.tvp));
}

extern asmlinkage long
compat_sys_wait4(compat_pid_t pid, compat_uint_t * stat_addr, int options,
                 struct compat_rusage *ru);

asmlinkage long
sys32_waitpid(compat_pid_t pid, unsigned int *stat_addr, int options)
{
        return compat_sys_wait4(pid, stat_addr, options, NULL);
}

int sys32_ni_syscall(int call)
{ 
        struct task_struct *me = current;
        static char lastcomm[sizeof(me->comm)];

        if (strncmp(lastcomm, me->comm, sizeof(lastcomm))) {
                printk(KERN_INFO "IA32 syscall %d from %s not implemented\n",
                       call, me->comm);
                strncpy(lastcomm, me->comm, sizeof(lastcomm));
        } 
        return -ENOSYS;        
} 

/* 32-bit timeval and related flotsam.  */

asmlinkage long
sys32_sysfs(int option, u32 arg1, u32 arg2)
{
        return sys_sysfs(option, arg1, arg2);
}

struct sysinfo32 {
        s32 uptime;
        u32 loads[3];
        u32 totalram;
        u32 freeram;
        u32 sharedram;
        u32 bufferram;
        u32 totalswap;
        u32 freeswap;
        unsigned short procs;
        unsigned short pad; 
        u32 totalhigh;
        u32 freehigh;
        u32 mem_unit;
        char _f[20-2*sizeof(u32)-sizeof(int)];
};

asmlinkage long
sys32_sysinfo(struct sysinfo32 __user *info)
{
        struct sysinfo s;
        int ret;
        mm_segment_t old_fs = get_fs ();
        int bitcount = 0;
        
        set_fs (KERNEL_DS);
        ret = sys_sysinfo(&s);
        set_fs (old_fs);

        /* 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)) {
                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 sysinfo32)) ||
            __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;
}
                
asmlinkage long
sys32_sched_rr_get_interval(compat_pid_t pid, struct compat_timespec __user *interval)
{
        struct timespec t;
        int ret;
        mm_segment_t old_fs = get_fs ();
        
        set_fs (KERNEL_DS);
        ret = sys_sched_rr_get_interval(pid, &t);
        set_fs (old_fs);
        if (put_compat_timespec(&t, interval))
                return -EFAULT;
        return ret;
}

asmlinkage long
sys32_rt_sigpending(compat_sigset_t __user *set, compat_size_t sigsetsize)
{
        sigset_t s;
        compat_sigset_t s32;
        int ret;
        mm_segment_t old_fs = get_fs();
                
        set_fs (KERNEL_DS);
        ret = sys_rt_sigpending(&s, sigsetsize);
        set_fs (old_fs);
        if (!ret) {
                switch (_NSIG_WORDS) {
                case 4: s32.sig[7] = (s.sig[3] >> 32); s32.sig[6] = s.sig[3];
                case 3: s32.sig[5] = (s.sig[2] >> 32); s32.sig[4] = s.sig[2];
                case 2: s32.sig[3] = (s.sig[1] >> 32); s32.sig[2] = s.sig[1];
                case 1: s32.sig[1] = (s.sig[0] >> 32); s32.sig[0] = s.sig[0];
                }
                if (copy_to_user (set, &s32, sizeof(compat_sigset_t)))
                        return -EFAULT;
        }
        return ret;
}

asmlinkage long
sys32_rt_sigqueueinfo(int pid, int sig, compat_siginfo_t __user *uinfo)
{
        siginfo_t info;
        int ret;
        mm_segment_t old_fs = get_fs();
        
        if (copy_siginfo_from_user32(&info, uinfo))
                return -EFAULT;
        set_fs (KERNEL_DS);
        ret = sys_rt_sigqueueinfo(pid, sig, &info);
        set_fs (old_fs);
        return ret;
}

/* These are here just in case some old ia32 binary calls it. */
asmlinkage long
sys32_pause(void)
{
        current->state = TASK_INTERRUPTIBLE;
        schedule();
        return -ERESTARTNOHAND;
}


#ifdef CONFIG_SYSCTL
struct sysctl_ia32 {
        unsigned int    name;
        int             nlen;
        unsigned int    oldval;
        unsigned int    oldlenp;
        unsigned int    newval;
        unsigned int    newlen;
        unsigned int    __unused[4];
};


asmlinkage long
sys32_sysctl(struct sysctl_ia32 __user *args32)
{
        struct sysctl_ia32 a32;
        mm_segment_t old_fs = get_fs ();
        void __user *oldvalp, *newvalp;
        size_t oldlen;
        int __user *namep;
        long ret;
        extern int do_sysctl(int *name, int nlen, void *oldval, size_t *oldlenp,
                     void *newval, size_t newlen);


        if (copy_from_user(&a32, args32, sizeof (a32)))
                return -EFAULT;

        /*
         * We need to pre-validate these because we have to disable address checking
         * before calling do_sysctl() because of OLDLEN but we can't run the risk of the
         * user specifying bad addresses here.  Well, since we're dealing with 32 bit
         * addresses, we KNOW that access_ok() will always succeed, so this is an
         * expensive NOP, but so what...
         */
        namep = compat_ptr(a32.name);
        oldvalp = compat_ptr(a32.oldval);
        newvalp =  compat_ptr(a32.newval);

        if ((oldvalp && get_user(oldlen, (int __user *)compat_ptr(a32.oldlenp)))
            || !access_ok(VERIFY_WRITE, namep, 0)
            || !access_ok(VERIFY_WRITE, oldvalp, 0)
            || !access_ok(VERIFY_WRITE, newvalp, 0))
                return -EFAULT;

        set_fs(KERNEL_DS);
        lock_kernel();
        ret = do_sysctl(namep, a32.nlen, oldvalp, &oldlen, newvalp, (size_t) a32.newlen);
        unlock_kernel();
        set_fs(old_fs);

        if (oldvalp && put_user (oldlen, (int __user *)compat_ptr(a32.oldlenp)))
                return -EFAULT;

        return ret;
}
#endif

/* warning: next two assume little endian */ 
asmlinkage long
sys32_pread(unsigned int fd, char __user *ubuf, u32 count, u32 poslo, u32 poshi)
{
        return sys_pread64(fd, ubuf, count,
                         ((loff_t)AA(poshi) << 32) | AA(poslo));
}

asmlinkage long
sys32_pwrite(unsigned int fd, char __user *ubuf, u32 count, u32 poslo, u32 poshi)
{
        return sys_pwrite64(fd, ubuf, count,
                          ((loff_t)AA(poshi) << 32) | AA(poslo));
}


asmlinkage long
sys32_personality(unsigned long personality)
{
        int ret;
        if (personality(current->personality) == PER_LINUX32 && 
                personality == PER_LINUX)
                personality = PER_LINUX32;
        ret = sys_personality(personality);
        if (ret == PER_LINUX32)
                ret = PER_LINUX;
        return ret;
}

asmlinkage long
sys32_sendfile(int out_fd, int in_fd, compat_off_t __user *offset, s32 count)
{
        mm_segment_t old_fs = get_fs();
        int ret;
        off_t of;
        
        if (offset && get_user(of, offset))
                return -EFAULT;
                
        set_fs(KERNEL_DS);
        ret = sys_sendfile(out_fd, in_fd, offset ? &of : NULL, count);
        set_fs(old_fs);
        
        if (offset && put_user(of, offset))
                return -EFAULT;
                
        return ret;
}

/* Handle adjtimex compatibility. */

struct timex32 {
        u32 modes;
        s32 offset, freq, maxerror, esterror;
        s32 status, constant, precision, tolerance;
        struct compat_timeval time;
        s32 tick;
        s32 ppsfreq, jitter, shift, stabil;
        s32 jitcnt, calcnt, errcnt, stbcnt;
        s32  :32; s32  :32; s32  :32; s32  :32;
        s32  :32; s32  :32; s32  :32; s32  :32;
        s32  :32; s32  :32; s32  :32; s32  :32;
};

extern int do_adjtimex(struct timex *);

asmlinkage long
sys32_adjtimex(struct timex32 __user *utp)
{
        struct timex txc;
        int ret;

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

        if (!access_ok(VERIFY_READ, utp, sizeof(struct timex32)) ||
           __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 timex32)) ||
           __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;
}

asmlinkage long sys32_mmap2(unsigned long addr, unsigned long len,
        unsigned long prot, unsigned long flags,
        unsigned long fd, unsigned long pgoff)
{
        struct mm_struct *mm = current->mm;
        unsigned long error;
        struct file * file = NULL;

        flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
        if (!(flags & MAP_ANONYMOUS)) {
                file = fget(fd);
                if (!file)
                        return -EBADF;
        }

        down_write(&mm->mmap_sem);
        error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
        up_write(&mm->mmap_sem);

        if (file)
                fput(file);
        return error;
}

asmlinkage long sys32_olduname(struct oldold_utsname __user * name)
{
        int error;

        if (!name)
                return -EFAULT;
        if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
                return -EFAULT;
  
        down_read(&uts_sem);
        
        error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
         __put_user(0,name->sysname+__OLD_UTS_LEN);
         __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
         __put_user(0,name->nodename+__OLD_UTS_LEN);
         __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
         __put_user(0,name->release+__OLD_UTS_LEN);
         __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
         __put_user(0,name->version+__OLD_UTS_LEN);
         { 
                 char *arch = "x86_64";
                 if (personality(current->personality) == PER_LINUX32)
                         arch = "i686";
                 
                 __copy_to_user(&name->machine,arch,strlen(arch)+1);
         }
        
         up_read(&uts_sem);
         
         error = error ? -EFAULT : 0;
         
         return error;
}

long sys32_uname(struct old_utsname __user * name)
{
        int err;
        if (!name)
                return -EFAULT;
        down_read(&uts_sem);
        err=copy_to_user(name, &system_utsname, sizeof (*name));
        up_read(&uts_sem);
        if (personality(current->personality) == PER_LINUX32) 
                err |= copy_to_user(&name->machine, "i686", 5);
        return err?-EFAULT:0;
}

long sys32_ustat(unsigned dev, struct ustat32 __user *u32p)
{
        struct ustat u;
        mm_segment_t seg;
        int ret;
        
        seg = get_fs(); 
        set_fs(KERNEL_DS); 
        ret = sys_ustat(dev,&u); 
        set_fs(seg);
        if (ret >= 0) { 
                if (!access_ok(VERIFY_WRITE,u32p,sizeof(struct ustat32)) || 
                    __put_user((__u32) u.f_tfree, &u32p->f_tfree) ||
                    __put_user((__u32) u.f_tinode, &u32p->f_tfree) ||
                    __copy_to_user(&u32p->f_fname, u.f_fname, sizeof(u.f_fname)) ||
                    __copy_to_user(&u32p->f_fpack, u.f_fpack, sizeof(u.f_fpack)))
                        ret = -EFAULT;
        }
        return ret;
} 

asmlinkage long sys32_execve(char __user *name, compat_uptr_t __user *argv,
                             compat_uptr_t __user *envp, struct pt_regs *regs)
{
        long error;
        char * filename;

        filename = getname(name);
        error = PTR_ERR(filename);
        if (IS_ERR(filename))
                return error;
        error = compat_do_execve(filename, argv, envp, regs);
        if (error == 0) {
                task_lock(current);
                current->ptrace &= ~PT_DTRACE;
                task_unlock(current);
        }
        putname(filename);
        return error;
}

asmlinkage long sys32_clone(unsigned int clone_flags, unsigned int newsp,
                            struct pt_regs *regs)
{
        void __user *parent_tid = (void __user *)regs->rdx;
        void __user *child_tid = (void __user *)regs->rdi;
        if (!newsp)
                newsp = regs->rsp;
        return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
}

/*
 * Some system calls that need sign extended arguments. This could be done by a generic wrapper.
 */ 

long sys32_lseek (unsigned int fd, int offset, unsigned int whence)
{
        return sys_lseek(fd, offset, whence);
}

long sys32_kill(int pid, int sig)
{
        return sys_kill(pid, sig);
}
 
long sys32_fadvise64_64(int fd, __u32 offset_low, __u32 offset_high, 
                        __u32 len_low, __u32 len_high, int advice)
{ 
        return sys_fadvise64_64(fd,
                               (((u64)offset_high)<<32) | offset_low,
                               (((u64)len_high)<<32) | len_low,
                               advice); 
} 

long sys32_vm86_warning(void)
{ 
        struct task_struct *me = current;
        static char lastcomm[sizeof(me->comm)];
        if (strncmp(lastcomm, me->comm, sizeof(lastcomm))) {
                printk(KERN_INFO "%s: vm86 mode not supported on 64 bit kernel\n",
                       me->comm);
                strncpy(lastcomm, me->comm, sizeof(lastcomm));
        } 
        return -ENOSYS;
} 

long sys32_lookup_dcookie(u32 addr_low, u32 addr_high,
                          char __user * buf, size_t len)
{
        return sys_lookup_dcookie(((u64)addr_high << 32) | addr_low, buf, len);
}

static int __init ia32_init (void)
{
        printk("IA32 emulation $Id: sys_ia32.c,v 1.32 2002/03/24 13:02:28 ak Exp $\n");  
        return 0;
}

__initcall(ia32_init);

extern unsigned long ia32_sys_call_table[];
EXPORT_SYMBOL(ia32_sys_call_table);