fed up with those stupid warnings

[mmotm.git] / arch / x86 / 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/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/signal.h>
#include <linux/syscalls.h>
#include <linux/times.h>
#include <linux/utsname.h>
#include <linux/smp_lock.h>
#include <linux/mm.h>
#include <linux/uio.h>
#include <linux/poll.h>
#include <linux/personality.h>
#include <linux/stat.h>
#include <linux/rwsem.h>
#include <linux/compat.h>
#include <linux/vfs.h>
#include <linux/ptrace.h>
#include <linux/highuid.h>
#include <linux/sysctl.h>
#include <asm/mman.h>
#include <asm/types.h>
#include <asm/uaccess.h>
#include <asm/atomic.h>
#include <asm/vgtod.h>
#include <asm/sys_ia32.h>

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


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;

        error = vfs_fstatat(dfd, filename, &stat, flag);
        if (error)
                return error;
        return cp_stat64(statbuf, &stat);
}

/*
 * 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_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 ? (sigset_t __user *)&s : NULL,
                                 oset ? (sigset_t __user *)&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;
}

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

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));
}

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

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

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

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, (struct timespec __user *)&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((sigset_t __user *)&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, (siginfo_t __user *)&info);
        set_fs(old_fs);
        return ret;
}

#ifdef CONFIG_SYSCTL_SYSCALL
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;

        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, (size_t __user *)&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 ? (off_t __user *)&of : NULL,
                           count);
        set_fs(old_fs);

        if (offset && put_user(of, offset))
                return -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)
{
        char *arch = "x86_64";
        int err;

        if (!name)
                return -EFAULT;
        if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
                return -EFAULT;

        down_read(&uts_sem);

        err = __copy_to_user(&name->sysname, &utsname()->sysname,
                             __OLD_UTS_LEN);
        err |= __put_user(0, name->sysname+__OLD_UTS_LEN);
        err |= __copy_to_user(&name->nodename, &utsname()->nodename,
                              __OLD_UTS_LEN);
        err |= __put_user(0, name->nodename+__OLD_UTS_LEN);
        err |= __copy_to_user(&name->release, &utsname()->release,
                              __OLD_UTS_LEN);
        err |= __put_user(0, name->release+__OLD_UTS_LEN);
        err |= __copy_to_user(&name->version, &utsname()->version,
                              __OLD_UTS_LEN);
        err |= __put_user(0, name->version+__OLD_UTS_LEN);

        if (personality(current->personality) == PER_LINUX32)
                arch = "i686";

        err |= __copy_to_user(&name->machine, arch, strlen(arch) + 1);

        up_read(&uts_sem);

        err = err ? -EFAULT : 0;

        return err;
}

long sys32_uname(struct old_utsname __user *name)
{
        int err;

        if (!name)
                return -EFAULT;
        down_read(&uts_sem);
        err = copy_to_user(name, 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;
}

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);
        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->dx;
        void __user *child_tid = (void __user *)regs->di;

        if (!newsp)
                newsp = regs->sp;
        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))) {
                compat_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);
}

asmlinkage ssize_t sys32_readahead(int fd, unsigned off_lo, unsigned off_hi,
                                   size_t count)
{
        return sys_readahead(fd, ((u64)off_hi << 32) | off_lo, count);
}

asmlinkage long sys32_sync_file_range(int fd, unsigned off_low, unsigned off_hi,
                                      unsigned n_low, unsigned n_hi,  int flags)
{
        return sys_sync_file_range(fd,
                                   ((u64)off_hi << 32) | off_low,
                                   ((u64)n_hi << 32) | n_low, flags);
}

asmlinkage long sys32_fadvise64(int fd, unsigned offset_lo, unsigned offset_hi,
                                size_t len, int advice)
{
        return sys_fadvise64_64(fd, ((u64)offset_hi << 32) | offset_lo,
                                len, advice);
}

asmlinkage long sys32_fallocate(int fd, int mode, unsigned offset_lo,
                                unsigned offset_hi, unsigned len_lo,
                                unsigned len_hi)
{
        return sys_fallocate(fd, mode, ((u64)offset_hi << 32) | offset_lo,
                             ((u64)len_hi << 32) | len_lo);
}