/*
   *  linux/fs/compat.c
   *
   *  Kernel compatibililty routines for e.g. 32 bit syscall support
   *  on 64 bit kernels.
   *
   *  Copyright (C) 2002       Stephen Rothwell, IBM Corporation
   *  Copyright (C) 1997-2000  Jakub Jelinek  (jakub@redhat.com)
   *  Copyright (C) 1998       Eddie C. Dost  (ecd@skynet.be)
   *  Copyright (C) 2001,2002  Andi Kleen, SuSE Labs 

   *  Copyright (C) 2003       Pavel Machek (pavel@ucw.cz)

   *
   *  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/stddef.h>

  #include <linux/kernel.h>

  #include <linux/linkage.h>
  #include <linux/compat.h>
  #include <linux/errno.h>
  #include <linux/time.h>
  #include <linux/fs.h>
  #include <linux/fcntl.h>
  #include <linux/namei.h>
  #include <linux/file.h>

  #include <linux/fdtable.h>

  #include <linux/vfs.h>

  #include <linux/ioctl.h>
  #include <linux/init.h>

  #include <linux/ncp_mount.h>

  #include <linux/nfs4_mount.h>

  #include <linux/syscalls.h>
  #include <linux/ctype.h>
  #include <linux/module.h>
  #include <linux/dirent.h>

  #include <linux/fsnotify.h>

  #include <linux/highuid.h>

  #include <linux/nfsd/syscall.h>
  #include <linux/personality.h>
  #include <linux/rwsem.h>

  #include <linux/tsacct_kern.h>

  #include <linux/security.h>

  #include <linux/highmem.h>

  #include <linux/signal.h>

  #include <linux/poll.h>

  #include <linux/mm.h>

  #include <linux/eventpoll.h>

  #include <linux/fs_struct.h>

  #include <linux/slab.h>

  #include <linux/pagemap.h>

  #include <asm/uaccess.h>
  #include <asm/mmu_context.h>
  #include <asm/ioctls.h>

  #include "internal.h"

  int compat_log = 1;
  
  int compat_printk(const char *fmt, ...)
  {
  	va_list ap;
  	int ret;
  	if (!compat_log)
  		return 0;
  	va_start(ap, fmt);
  	ret = vprintk(fmt, ap);
  	va_end(ap);
  	return ret;
  }

  #include "read_write.h"

  /*
   * Not all architectures have sys_utime, so implement this in terms
   * of sys_utimes.
   */

  asmlinkage long compat_sys_utime(const char __user *filename,
  				 struct compat_utimbuf __user *t)

  {

  	struct timespec tv[2];

  
  	if (t) {
  		if (get_user(tv[0].tv_sec, &t->actime) ||
  		    get_user(tv[1].tv_sec, &t->modtime))
  			return -EFAULT;

  		tv[0].tv_nsec = 0;
  		tv[1].tv_nsec = 0;

  	}

  	return do_utimes(AT_FDCWD, filename, t ? tv : NULL, 0);
  }

  asmlinkage long compat_sys_utimensat(unsigned int dfd, const char __user *filename, struct compat_timespec __user *t, int flags)

  {
  	struct timespec tv[2];
  
  	if  (t) {
  		if (get_compat_timespec(&tv[0], &t[0]) ||
  		    get_compat_timespec(&tv[1], &t[1]))
  			return -EFAULT;

  		if (tv[0].tv_nsec == UTIME_OMIT && tv[1].tv_nsec == UTIME_OMIT)
  			return 0;
  	}
  	return do_utimes(dfd, filename, t ? tv : NULL, flags);

  }

  asmlinkage long compat_sys_futimesat(unsigned int dfd, const char __user *filename, struct compat_timeval __user *t)

  {

  	struct timespec tv[2];

  	if (t) {

  		if (get_user(tv[0].tv_sec, &t[0].tv_sec) ||

  		    get_user(tv[0].tv_nsec, &t[0].tv_usec) ||

  		    get_user(tv[1].tv_sec, &t[1].tv_sec) ||

  		    get_user(tv[1].tv_nsec, &t[1].tv_usec))

  			return -EFAULT;

  		if (tv[0].tv_nsec >= 1000000 || tv[0].tv_nsec < 0 ||
  		    tv[1].tv_nsec >= 1000000 || tv[1].tv_nsec < 0)
  			return -EINVAL;
  		tv[0].tv_nsec *= 1000;
  		tv[1].tv_nsec *= 1000;

  	}

  	return do_utimes(dfd, filename, t ? tv : NULL, 0);

  }

  asmlinkage long compat_sys_utimes(const char __user *filename, struct compat_timeval __user *t)

  {
  	return compat_sys_futimesat(AT_FDCWD, filename, t);

  }

  static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
  {
  	compat_ino_t ino = stat->ino;
  	typeof(ubuf->st_uid) uid = 0;
  	typeof(ubuf->st_gid) gid = 0;
  	int err;
  
  	SET_UID(uid, stat->uid);
  	SET_GID(gid, stat->gid);
  
  	if ((u64) stat->size > MAX_NON_LFS ||
  	    !old_valid_dev(stat->dev) ||
  	    !old_valid_dev(stat->rdev))
  		return -EOVERFLOW;
  	if (sizeof(ino) < sizeof(stat->ino) && ino != stat->ino)
  		return -EOVERFLOW;
  
  	if (clear_user(ubuf, sizeof(*ubuf)))
  		return -EFAULT;
  
  	err  = __put_user(old_encode_dev(stat->dev), &ubuf->st_dev);
  	err |= __put_user(ino, &ubuf->st_ino);
  	err |= __put_user(stat->mode, &ubuf->st_mode);
  	err |= __put_user(stat->nlink, &ubuf->st_nlink);
  	err |= __put_user(uid, &ubuf->st_uid);
  	err |= __put_user(gid, &ubuf->st_gid);
  	err |= __put_user(old_encode_dev(stat->rdev), &ubuf->st_rdev);
  	err |= __put_user(stat->size, &ubuf->st_size);
  	err |= __put_user(stat->atime.tv_sec, &ubuf->st_atime);
  	err |= __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec);
  	err |= __put_user(stat->mtime.tv_sec, &ubuf->st_mtime);
  	err |= __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec);
  	err |= __put_user(stat->ctime.tv_sec, &ubuf->st_ctime);
  	err |= __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec);
  	err |= __put_user(stat->blksize, &ubuf->st_blksize);
  	err |= __put_user(stat->blocks, &ubuf->st_blocks);
  	return err;
  }

  asmlinkage long compat_sys_newstat(const char __user * filename,

  		struct compat_stat __user *statbuf)
  {
  	struct kstat stat;

  	int error;

  	error = vfs_stat(filename, &stat);
  	if (error)
  		return error;
  	return cp_compat_stat(&stat, statbuf);

  }

  asmlinkage long compat_sys_newlstat(const char __user * filename,

  		struct compat_stat __user *statbuf)
  {
  	struct kstat stat;

  	int error;

  	error = vfs_lstat(filename, &stat);
  	if (error)
  		return error;
  	return cp_compat_stat(&stat, statbuf);

  }

  #ifndef __ARCH_WANT_STAT64

  asmlinkage long compat_sys_newfstatat(unsigned int dfd,
  		const char __user *filename,

  		struct compat_stat __user *statbuf, int flag)
  {
  	struct kstat stat;

  	int error;

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

  }

  #endif

  asmlinkage long compat_sys_newfstat(unsigned int fd,
  		struct compat_stat __user * statbuf)
  {
  	struct kstat stat;
  	int error = vfs_fstat(fd, &stat);
  
  	if (!error)
  		error = cp_compat_stat(&stat, statbuf);
  	return error;
  }
  
  static int put_compat_statfs(struct compat_statfs __user *ubuf, struct kstatfs *kbuf)
  {
  	
  	if (sizeof ubuf->f_blocks == 4) {

  		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
  		     kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)

  			return -EOVERFLOW;
  		/* f_files and f_ffree may be -1; it's okay
  		 * to stuff that into 32 bits */
  		if (kbuf->f_files != 0xffffffffffffffffULL
  		 && (kbuf->f_files & 0xffffffff00000000ULL))
  			return -EOVERFLOW;
  		if (kbuf->f_ffree != 0xffffffffffffffffULL
  		 && (kbuf->f_ffree & 0xffffffff00000000ULL))
  			return -EOVERFLOW;
  	}
  	if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
  	    __put_user(kbuf->f_type, &ubuf->f_type) ||
  	    __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
  	    __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
  	    __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
  	    __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
  	    __put_user(kbuf->f_files, &ubuf->f_files) ||
  	    __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
  	    __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
  	    __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
  	    __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||
  	    __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
  	    __put_user(0, &ubuf->f_spare[0]) || 
  	    __put_user(0, &ubuf->f_spare[1]) || 
  	    __put_user(0, &ubuf->f_spare[2]) || 
  	    __put_user(0, &ubuf->f_spare[3]) || 
  	    __put_user(0, &ubuf->f_spare[4]))
  		return -EFAULT;
  	return 0;
  }
  
  /*

   * The following statfs calls are copies of code from fs/statfs.c and

   * should be checked against those from time to time
   */

  asmlinkage long compat_sys_statfs(const char __user *pathname, struct compat_statfs __user *buf)

  {

  	struct kstatfs tmp;
  	int error = user_statfs(pathname, &tmp);
  	if (!error)
  		error = put_compat_statfs(buf, &tmp);

  	return error;
  }
  
  asmlinkage long compat_sys_fstatfs(unsigned int fd, struct compat_statfs __user *buf)
  {

  	struct kstatfs tmp;

  	int error = fd_statfs(fd, &tmp);

  	if (!error)
  		error = put_compat_statfs(buf, &tmp);

  	return error;
  }
  
  static int put_compat_statfs64(struct compat_statfs64 __user *ubuf, struct kstatfs *kbuf)
  {
  	if (sizeof ubuf->f_blocks == 4) {

  		if ((kbuf->f_blocks | kbuf->f_bfree | kbuf->f_bavail |
  		     kbuf->f_bsize | kbuf->f_frsize) & 0xffffffff00000000ULL)

  			return -EOVERFLOW;
  		/* f_files and f_ffree may be -1; it's okay
  		 * to stuff that into 32 bits */
  		if (kbuf->f_files != 0xffffffffffffffffULL
  		 && (kbuf->f_files & 0xffffffff00000000ULL))
  			return -EOVERFLOW;
  		if (kbuf->f_ffree != 0xffffffffffffffffULL
  		 && (kbuf->f_ffree & 0xffffffff00000000ULL))
  			return -EOVERFLOW;
  	}
  	if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)) ||
  	    __put_user(kbuf->f_type, &ubuf->f_type) ||
  	    __put_user(kbuf->f_bsize, &ubuf->f_bsize) ||
  	    __put_user(kbuf->f_blocks, &ubuf->f_blocks) ||
  	    __put_user(kbuf->f_bfree, &ubuf->f_bfree) ||
  	    __put_user(kbuf->f_bavail, &ubuf->f_bavail) ||
  	    __put_user(kbuf->f_files, &ubuf->f_files) ||
  	    __put_user(kbuf->f_ffree, &ubuf->f_ffree) ||
  	    __put_user(kbuf->f_namelen, &ubuf->f_namelen) ||
  	    __put_user(kbuf->f_fsid.val[0], &ubuf->f_fsid.val[0]) ||
  	    __put_user(kbuf->f_fsid.val[1], &ubuf->f_fsid.val[1]) ||

  	    __put_user(kbuf->f_frsize, &ubuf->f_frsize) ||
  	    __put_user(kbuf->f_flags, &ubuf->f_flags) ||
  	    __clear_user(ubuf->f_spare, sizeof(ubuf->f_spare)))

  		return -EFAULT;
  	return 0;
  }

  asmlinkage long compat_sys_statfs64(const char __user *pathname, compat_size_t sz, struct compat_statfs64 __user *buf)

  {

  	struct kstatfs tmp;

  	int error;
  
  	if (sz != sizeof(*buf))
  		return -EINVAL;

  	error = user_statfs(pathname, &tmp);
  	if (!error)
  		error = put_compat_statfs64(buf, &tmp);

  	return error;
  }
  
  asmlinkage long compat_sys_fstatfs64(unsigned int fd, compat_size_t sz, struct compat_statfs64 __user *buf)
  {

  	struct kstatfs tmp;
  	int error;
  
  	if (sz != sizeof(*buf))
  		return -EINVAL;

  	error = fd_statfs(fd, &tmp);

  	if (!error)
  		error = put_compat_statfs64(buf, &tmp);

  	return error;
  }

  /*
   * This is a copy of sys_ustat, just dealing with a structure layout.
   * Given how simple this syscall is that apporach is more maintainable
   * than the various conversion hacks.
   */
  asmlinkage long compat_sys_ustat(unsigned dev, struct compat_ustat __user *u)
  {
  	struct super_block *sb;
  	struct compat_ustat tmp;
  	struct kstatfs sbuf;
  	int err;
  
  	sb = user_get_super(new_decode_dev(dev));
  	if (!sb)
  		return -EINVAL;

  	err = statfs_by_dentry(sb->s_root, &sbuf);

  	drop_super(sb);
  	if (err)
  		return err;
  
  	memset(&tmp, 0, sizeof(struct compat_ustat));
  	tmp.f_tfree = sbuf.f_bfree;
  	tmp.f_tinode = sbuf.f_ffree;
  	if (copy_to_user(u, &tmp, sizeof(struct compat_ustat)))
  		return -EFAULT;
  	return 0;
  }

  static int get_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
  {
  	if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
  	    __get_user(kfl->l_type, &ufl->l_type) ||
  	    __get_user(kfl->l_whence, &ufl->l_whence) ||
  	    __get_user(kfl->l_start, &ufl->l_start) ||
  	    __get_user(kfl->l_len, &ufl->l_len) ||
  	    __get_user(kfl->l_pid, &ufl->l_pid))
  		return -EFAULT;
  	return 0;
  }
  
  static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
  {
  	if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
  	    __put_user(kfl->l_type, &ufl->l_type) ||
  	    __put_user(kfl->l_whence, &ufl->l_whence) ||
  	    __put_user(kfl->l_start, &ufl->l_start) ||
  	    __put_user(kfl->l_len, &ufl->l_len) ||
  	    __put_user(kfl->l_pid, &ufl->l_pid))
  		return -EFAULT;
  	return 0;
  }
  
  #ifndef HAVE_ARCH_GET_COMPAT_FLOCK64
  static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
  {
  	if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
  	    __get_user(kfl->l_type, &ufl->l_type) ||
  	    __get_user(kfl->l_whence, &ufl->l_whence) ||
  	    __get_user(kfl->l_start, &ufl->l_start) ||
  	    __get_user(kfl->l_len, &ufl->l_len) ||
  	    __get_user(kfl->l_pid, &ufl->l_pid))
  		return -EFAULT;
  	return 0;
  }
  #endif
  
  #ifndef HAVE_ARCH_PUT_COMPAT_FLOCK64
  static int put_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
  {
  	if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
  	    __put_user(kfl->l_type, &ufl->l_type) ||
  	    __put_user(kfl->l_whence, &ufl->l_whence) ||
  	    __put_user(kfl->l_start, &ufl->l_start) ||
  	    __put_user(kfl->l_len, &ufl->l_len) ||
  	    __put_user(kfl->l_pid, &ufl->l_pid))
  		return -EFAULT;
  	return 0;
  }
  #endif
  
  asmlinkage long compat_sys_fcntl64(unsigned int fd, unsigned int cmd,
  		unsigned long arg)
  {
  	mm_segment_t old_fs;
  	struct flock f;
  	long ret;
  
  	switch (cmd) {
  	case F_GETLK:
  	case F_SETLK:
  	case F_SETLKW:
  		ret = get_compat_flock(&f, compat_ptr(arg));
  		if (ret != 0)
  			break;
  		old_fs = get_fs();
  		set_fs(KERNEL_DS);
  		ret = sys_fcntl(fd, cmd, (unsigned long)&f);
  		set_fs(old_fs);
  		if (cmd == F_GETLK && ret == 0) {

  			/* GETLK was successful and we need to return the data...

  			 * but it needs to fit in the compat structure.
  			 * l_start shouldn't be too big, unless the original
  			 * start + end is greater than COMPAT_OFF_T_MAX, in which
  			 * case the app was asking for trouble, so we return
  			 * -EOVERFLOW in that case.
  			 * l_len could be too big, in which case we just truncate it,
  			 * and only allow the app to see that part of the conflicting
  			 * lock that might make sense to it anyway
  			 */
  
  			if (f.l_start > COMPAT_OFF_T_MAX)

  				ret = -EOVERFLOW;

  			if (f.l_len > COMPAT_OFF_T_MAX)
  				f.l_len = COMPAT_OFF_T_MAX;

  			if (ret == 0)
  				ret = put_compat_flock(&f, compat_ptr(arg));
  		}
  		break;
  
  	case F_GETLK64:
  	case F_SETLK64:
  	case F_SETLKW64:
  		ret = get_compat_flock64(&f, compat_ptr(arg));
  		if (ret != 0)
  			break;
  		old_fs = get_fs();
  		set_fs(KERNEL_DS);
  		ret = sys_fcntl(fd, (cmd == F_GETLK64) ? F_GETLK :
  				((cmd == F_SETLK64) ? F_SETLK : F_SETLKW),
  				(unsigned long)&f);
  		set_fs(old_fs);
  		if (cmd == F_GETLK64 && ret == 0) {

  			/* need to return lock information - see above for commentary */
  			if (f.l_start > COMPAT_LOFF_T_MAX)

  				ret = -EOVERFLOW;

  			if (f.l_len > COMPAT_LOFF_T_MAX)
  				f.l_len = COMPAT_LOFF_T_MAX;

  			if (ret == 0)
  				ret = put_compat_flock64(&f, compat_ptr(arg));
  		}
  		break;
  
  	default:
  		ret = sys_fcntl(fd, cmd, arg);
  		break;
  	}
  	return ret;
  }
  
  asmlinkage long compat_sys_fcntl(unsigned int fd, unsigned int cmd,
  		unsigned long arg)
  {
  	if ((cmd == F_GETLK64) || (cmd == F_SETLK64) || (cmd == F_SETLKW64))
  		return -EINVAL;
  	return compat_sys_fcntl64(fd, cmd, arg);
  }
  
  asmlinkage long
  compat_sys_io_setup(unsigned nr_reqs, u32 __user *ctx32p)
  {
  	long ret;
  	aio_context_t ctx64;
  
  	mm_segment_t oldfs = get_fs();
  	if (unlikely(get_user(ctx64, ctx32p)))
  		return -EFAULT;
  
  	set_fs(KERNEL_DS);
  	/* The __user pointer cast is valid because of the set_fs() */
  	ret = sys_io_setup(nr_reqs, (aio_context_t __user *) &ctx64);
  	set_fs(oldfs);
  	/* truncating is ok because it's a user address */
  	if (!ret)
  		ret = put_user((u32) ctx64, ctx32p);
  	return ret;
  }
  
  asmlinkage long
  compat_sys_io_getevents(aio_context_t ctx_id,
  				 unsigned long min_nr,
  				 unsigned long nr,
  				 struct io_event __user *events,
  				 struct compat_timespec __user *timeout)
  {
  	long ret;
  	struct timespec t;
  	struct timespec __user *ut = NULL;
  
  	ret = -EFAULT;
  	if (unlikely(!access_ok(VERIFY_WRITE, events, 
  				nr * sizeof(struct io_event))))
  		goto out;
  	if (timeout) {
  		if (get_compat_timespec(&t, timeout))
  			goto out;
  
  		ut = compat_alloc_user_space(sizeof(*ut));
  		if (copy_to_user(ut, &t, sizeof(t)) )
  			goto out;
  	} 
  	ret = sys_io_getevents(ctx_id, min_nr, nr, events, ut);
  out:
  	return ret;
  }

  /* A write operation does a read from user space and vice versa */
  #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ)
  
  ssize_t compat_rw_copy_check_uvector(int type,
  		const struct compat_iovec __user *uvector, unsigned long nr_segs,
  		unsigned long fast_segs, struct iovec *fast_pointer,
  		struct iovec **ret_pointer)
  {
  	compat_ssize_t tot_len;
  	struct iovec *iov = *ret_pointer = fast_pointer;
  	ssize_t ret = 0;
  	int seg;
  
  	/*
  	 * SuS says "The readv() function *may* fail if the iovcnt argument
  	 * was less than or equal to 0, or greater than {IOV_MAX}.  Linux has
  	 * traditionally returned zero for zero segments, so...
  	 */
  	if (nr_segs == 0)
  		goto out;
  
  	ret = -EINVAL;
  	if (nr_segs > UIO_MAXIOV || nr_segs < 0)
  		goto out;
  	if (nr_segs > fast_segs) {
  		ret = -ENOMEM;
  		iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL);

  		if (iov == NULL)

  			goto out;

  	}
  	*ret_pointer = iov;
  
  	/*
  	 * Single unix specification:
  	 * We should -EINVAL if an element length is not >= 0 and fitting an

  	 * ssize_t.

  	 *

  	 * In Linux, the total length is limited to MAX_RW_COUNT, there is
  	 * no overflow possibility.

  	 */
  	tot_len = 0;
  	ret = -EINVAL;
  	for (seg = 0; seg < nr_segs; seg++) {

  		compat_uptr_t buf;
  		compat_ssize_t len;
  
  		if (__get_user(len, &uvector->iov_len) ||
  		   __get_user(buf, &uvector->iov_base)) {
  			ret = -EFAULT;
  			goto out;
  		}
  		if (len < 0)	/* size_t not fitting in compat_ssize_t .. */
  			goto out;

  		if (!access_ok(vrfy_dir(type), compat_ptr(buf), len)) {

  			ret = -EFAULT;
  			goto out;
  		}

  		if (len > MAX_RW_COUNT - tot_len)
  			len = MAX_RW_COUNT - tot_len;
  		tot_len += len;

  		iov->iov_base = compat_ptr(buf);
  		iov->iov_len = (compat_size_t) len;
  		uvector++;
  		iov++;
  	}
  	ret = tot_len;
  
  out:
  	return ret;
  }

  static inline long
  copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64)
  {
  	compat_uptr_t uptr;
  	int i;
  
  	for (i = 0; i < nr; ++i) {
  		if (get_user(uptr, ptr32 + i))
  			return -EFAULT;
  		if (put_user(compat_ptr(uptr), ptr64 + i))
  			return -EFAULT;
  	}
  	return 0;
  }
  
  #define MAX_AIO_SUBMITS 	(PAGE_SIZE/sizeof(struct iocb *))
  
  asmlinkage long
  compat_sys_io_submit(aio_context_t ctx_id, int nr, u32 __user *iocb)
  {
  	struct iocb __user * __user *iocb64; 
  	long ret;
  
  	if (unlikely(nr < 0))
  		return -EINVAL;
  
  	if (nr > MAX_AIO_SUBMITS)
  		nr = MAX_AIO_SUBMITS;
  	
  	iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64));
  	ret = copy_iocb(nr, iocb, iocb64);
  	if (!ret)

  		ret = do_io_submit(ctx_id, nr, iocb64, 1);

  	return ret;
  }
  
  struct compat_ncp_mount_data {
  	compat_int_t version;
  	compat_uint_t ncp_fd;

  	__compat_uid_t mounted_uid;

  	compat_pid_t wdog_pid;
  	unsigned char mounted_vol[NCP_VOLNAME_LEN + 1];
  	compat_uint_t time_out;
  	compat_uint_t retry_count;
  	compat_uint_t flags;

  	__compat_uid_t uid;
  	__compat_gid_t gid;

  	compat_mode_t file_mode;
  	compat_mode_t dir_mode;
  };
  
  struct compat_ncp_mount_data_v4 {
  	compat_int_t version;
  	compat_ulong_t flags;
  	compat_ulong_t mounted_uid;
  	compat_long_t wdog_pid;
  	compat_uint_t ncp_fd;
  	compat_uint_t time_out;
  	compat_uint_t retry_count;
  	compat_ulong_t uid;
  	compat_ulong_t gid;
  	compat_ulong_t file_mode;
  	compat_ulong_t dir_mode;
  };
  
  static void *do_ncp_super_data_conv(void *raw_data)
  {
  	int version = *(unsigned int *)raw_data;
  
  	if (version == 3) {
  		struct compat_ncp_mount_data *c_n = raw_data;
  		struct ncp_mount_data *n = raw_data;
  
  		n->dir_mode = c_n->dir_mode;
  		n->file_mode = c_n->file_mode;
  		n->gid = c_n->gid;
  		n->uid = c_n->uid;
  		memmove (n->mounted_vol, c_n->mounted_vol, (sizeof (c_n->mounted_vol) + 3 * sizeof (unsigned int)));
  		n->wdog_pid = c_n->wdog_pid;
  		n->mounted_uid = c_n->mounted_uid;
  	} else if (version == 4) {
  		struct compat_ncp_mount_data_v4 *c_n = raw_data;
  		struct ncp_mount_data_v4 *n = raw_data;
  
  		n->dir_mode = c_n->dir_mode;
  		n->file_mode = c_n->file_mode;
  		n->gid = c_n->gid;
  		n->uid = c_n->uid;
  		n->retry_count = c_n->retry_count;
  		n->time_out = c_n->time_out;
  		n->ncp_fd = c_n->ncp_fd;
  		n->wdog_pid = c_n->wdog_pid;
  		n->mounted_uid = c_n->mounted_uid;
  		n->flags = c_n->flags;
  	} else if (version != 5) {
  		return NULL;
  	}
  
  	return raw_data;
  }

  struct compat_nfs_string {
  	compat_uint_t len;

  	compat_uptr_t data;

  };
  
  static inline void compat_nfs_string(struct nfs_string *dst,
  				     struct compat_nfs_string *src)
  {
  	dst->data = compat_ptr(src->data);
  	dst->len = src->len;
  }
  
  struct compat_nfs4_mount_data_v1 {
  	compat_int_t version;
  	compat_int_t flags;
  	compat_int_t rsize;
  	compat_int_t wsize;
  	compat_int_t timeo;
  	compat_int_t retrans;
  	compat_int_t acregmin;
  	compat_int_t acregmax;
  	compat_int_t acdirmin;
  	compat_int_t acdirmax;
  	struct compat_nfs_string client_addr;
  	struct compat_nfs_string mnt_path;
  	struct compat_nfs_string hostname;
  	compat_uint_t host_addrlen;

  	compat_uptr_t host_addr;

  	compat_int_t proto;
  	compat_int_t auth_flavourlen;

  	compat_uptr_t auth_flavours;

  };
  
  static int do_nfs4_super_data_conv(void *raw_data)
  {
  	int version = *(compat_uint_t *) raw_data;
  
  	if (version == 1) {
  		struct compat_nfs4_mount_data_v1 *raw = raw_data;
  		struct nfs4_mount_data *real = raw_data;
  
  		/* copy the fields backwards */
  		real->auth_flavours = compat_ptr(raw->auth_flavours);
  		real->auth_flavourlen = raw->auth_flavourlen;
  		real->proto = raw->proto;
  		real->host_addr = compat_ptr(raw->host_addr);
  		real->host_addrlen = raw->host_addrlen;
  		compat_nfs_string(&real->hostname, &raw->hostname);
  		compat_nfs_string(&real->mnt_path, &raw->mnt_path);
  		compat_nfs_string(&real->client_addr, &raw->client_addr);
  		real->acdirmax = raw->acdirmax;
  		real->acdirmin = raw->acdirmin;
  		real->acregmax = raw->acregmax;
  		real->acregmin = raw->acregmin;
  		real->retrans = raw->retrans;
  		real->timeo = raw->timeo;
  		real->wsize = raw->wsize;
  		real->rsize = raw->rsize;
  		real->flags = raw->flags;
  		real->version = raw->version;
  	}

  
  	return 0;
  }

  #define NCPFS_NAME      "ncpfs"

  #define NFS4_NAME	"nfs4"

  asmlinkage long compat_sys_mount(const char __user * dev_name,
  				 const char __user * dir_name,
  				 const char __user * type, unsigned long flags,
  				 const void __user * data)

  {

  	char *kernel_type;

  	unsigned long data_page;

  	char *kernel_dev;

  	char *dir_page;
  	int retval;

  	retval = copy_mount_string(type, &kernel_type);

  	if (retval < 0)
  		goto out;
  
  	dir_page = getname(dir_name);
  	retval = PTR_ERR(dir_page);
  	if (IS_ERR(dir_page))
  		goto out1;

  	retval = copy_mount_string(dev_name, &kernel_dev);

  	if (retval < 0)
  		goto out2;

  	retval = copy_mount_options(data, &data_page);

  	if (retval < 0)
  		goto out3;
  
  	retval = -EINVAL;

  	if (kernel_type && data_page) {

  		if (!strcmp(kernel_type, NCPFS_NAME)) {

  			do_ncp_super_data_conv((void *)data_page);

  		} else if (!strcmp(kernel_type, NFS4_NAME)) {

  			if (do_nfs4_super_data_conv((void *) data_page))
  				goto out4;

  		}
  	}

  	retval = do_mount(kernel_dev, dir_page, kernel_type,

  			flags, (void*)data_page);

   out4:

  	free_page(data_page);
   out3:

  	kfree(kernel_dev);

   out2:
  	putname(dir_page);
   out1:

  	kfree(kernel_type);

   out:
  	return retval;
  }

  struct compat_old_linux_dirent {
  	compat_ulong_t	d_ino;
  	compat_ulong_t	d_offset;
  	unsigned short	d_namlen;
  	char		d_name[1];
  };
  
  struct compat_readdir_callback {
  	struct compat_old_linux_dirent __user *dirent;
  	int result;
  };
  
  static int compat_fillonedir(void *__buf, const char *name, int namlen,

  			loff_t offset, u64 ino, unsigned int d_type)

  {
  	struct compat_readdir_callback *buf = __buf;
  	struct compat_old_linux_dirent __user *dirent;

  	compat_ulong_t d_ino;

  
  	if (buf->result)
  		return -EINVAL;

  	d_ino = ino;

  	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
  		buf->result = -EOVERFLOW;

  		return -EOVERFLOW;

  	}

  	buf->result++;
  	dirent = buf->dirent;
  	if (!access_ok(VERIFY_WRITE, dirent,
  			(unsigned long)(dirent->d_name + namlen + 1) -
  				(unsigned long)dirent))
  		goto efault;

  	if (	__put_user(d_ino, &dirent->d_ino) ||

  		__put_user(offset, &dirent->d_offset) ||
  		__put_user(namlen, &dirent->d_namlen) ||
  		__copy_to_user(dirent->d_name, name, namlen) ||
  		__put_user(0, dirent->d_name + namlen))
  		goto efault;
  	return 0;
  efault:
  	buf->result = -EFAULT;
  	return -EFAULT;
  }
  
  asmlinkage long compat_sys_old_readdir(unsigned int fd,
  	struct compat_old_linux_dirent __user *dirent, unsigned int count)
  {
  	int error;
  	struct file *file;
  	struct compat_readdir_callback buf;
  
  	error = -EBADF;
  	file = fget(fd);
  	if (!file)
  		goto out;
  
  	buf.result = 0;
  	buf.dirent = dirent;
  
  	error = vfs_readdir(file, compat_fillonedir, &buf);

  	if (buf.result)

  		error = buf.result;
  
  	fput(file);
  out:
  	return error;
  }
  
  struct compat_linux_dirent {
  	compat_ulong_t	d_ino;
  	compat_ulong_t	d_off;
  	unsigned short	d_reclen;
  	char		d_name[1];
  };
  
  struct compat_getdents_callback {
  	struct compat_linux_dirent __user *current_dir;
  	struct compat_linux_dirent __user *previous;
  	int count;
  	int error;
  };
  
  static int compat_filldir(void *__buf, const char *name, int namlen,

  		loff_t offset, u64 ino, unsigned int d_type)

  {
  	struct compat_linux_dirent __user * dirent;
  	struct compat_getdents_callback *buf = __buf;

  	compat_ulong_t d_ino;

  	int reclen = ALIGN(offsetof(struct compat_linux_dirent, d_name) +
  		namlen + 2, sizeof(compat_long_t));

  
  	buf->error = -EINVAL;	/* only used if we fail.. */
  	if (reclen > buf->count)
  		return -EINVAL;

  	d_ino = ino;

  	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
  		buf->error = -EOVERFLOW;

  		return -EOVERFLOW;

  	}

  	dirent = buf->previous;
  	if (dirent) {
  		if (__put_user(offset, &dirent->d_off))
  			goto efault;
  	}
  	dirent = buf->current_dir;

  	if (__put_user(d_ino, &dirent->d_ino))

  		goto efault;
  	if (__put_user(reclen, &dirent->d_reclen))
  		goto efault;
  	if (copy_to_user(dirent->d_name, name, namlen))
  		goto efault;
  	if (__put_user(0, dirent->d_name + namlen))
  		goto efault;
  	if (__put_user(d_type, (char  __user *) dirent + reclen - 1))
  		goto efault;
  	buf->previous = dirent;
  	dirent = (void __user *)dirent + reclen;
  	buf->current_dir = dirent;
  	buf->count -= reclen;
  	return 0;
  efault:
  	buf->error = -EFAULT;
  	return -EFAULT;
  }
  
  asmlinkage long compat_sys_getdents(unsigned int fd,
  		struct compat_linux_dirent __user *dirent, unsigned int count)
  {
  	struct file * file;
  	struct compat_linux_dirent __user * lastdirent;
  	struct compat_getdents_callback buf;
  	int error;
  
  	error = -EFAULT;
  	if (!access_ok(VERIFY_WRITE, dirent, count))
  		goto out;
  
  	error = -EBADF;
  	file = fget(fd);
  	if (!file)
  		goto out;
  
  	buf.current_dir = dirent;
  	buf.previous = NULL;
  	buf.count = count;
  	buf.error = 0;
  
  	error = vfs_readdir(file, compat_filldir, &buf);

  	if (error >= 0)
  		error = buf.error;

  	lastdirent = buf.previous;
  	if (lastdirent) {
  		if (put_user(file->f_pos, &lastdirent->d_off))
  			error = -EFAULT;
  		else
  			error = count - buf.count;
  	}

  	fput(file);
  out:
  	return error;
  }
  
  #ifndef __ARCH_OMIT_COMPAT_SYS_GETDENTS64

  
  struct compat_getdents_callback64 {
  	struct linux_dirent64 __user *current_dir;
  	struct linux_dirent64 __user *previous;
  	int count;
  	int error;
  };
  
  static int compat_filldir64(void * __buf, const char * name, int namlen, loff_t offset,

  		     u64 ino, unsigned int d_type)

  {
  	struct linux_dirent64 __user *dirent;
  	struct compat_getdents_callback64 *buf = __buf;

  	int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1,
  		sizeof(u64));

  	u64 off;
  
  	buf->error = -EINVAL;	/* only used if we fail.. */
  	if (reclen > buf->count)
  		return -EINVAL;
  	dirent = buf->previous;
  
  	if (dirent) {
  		if (__put_user_unaligned(offset, &dirent->d_off))
  			goto efault;
  	}
  	dirent = buf->current_dir;
  	if (__put_user_unaligned(ino, &dirent->d_ino))
  		goto efault;
  	off = 0;
  	if (__put_user_unaligned(off, &dirent->d_off))
  		goto efault;
  	if (__put_user(reclen, &dirent->d_reclen))
  		goto efault;
  	if (__put_user(d_type, &dirent->d_type))
  		goto efault;
  	if (copy_to_user(dirent->d_name, name, namlen))
  		goto efault;
  	if (__put_user(0, dirent->d_name + namlen))
  		goto efault;
  	buf->previous = dirent;
  	dirent = (void __user *)dirent + reclen;
  	buf->current_dir = dirent;
  	buf->count -= reclen;
  	return 0;
  efault:
  	buf->error = -EFAULT;
  	return -EFAULT;
  }
  
  asmlinkage long compat_sys_getdents64(unsigned int fd,
  		struct linux_dirent64 __user * dirent, unsigned int count)
  {
  	struct file * file;
  	struct linux_dirent64 __user * lastdirent;
  	struct compat_getdents_callback64 buf;
  	int error;
  
  	error = -EFAULT;
  	if (!access_ok(VERIFY_WRITE, dirent, count))
  		goto out;
  
  	error = -EBADF;
  	file = fget(fd);
  	if (!file)
  		goto out;
  
  	buf.current_dir = dirent;
  	buf.previous = NULL;
  	buf.count = count;
  	buf.error = 0;
  
  	error = vfs_readdir(file, compat_filldir64, &buf);

  	if (error >= 0)
  		error = buf.error;

  	lastdirent = buf.previous;
  	if (lastdirent) {
  		typeof(lastdirent->d_off) d_off = file->f_pos;

  		if (__put_user_unaligned(d_off, &lastdirent->d_off))

  			error = -EFAULT;
  		else
  			error = count - buf.count;

  	}

  	fput(file);
  out:
  	return error;
  }
  #endif /* ! __ARCH_OMIT_COMPAT_SYS_GETDENTS64 */
  
  static ssize_t compat_do_readv_writev(int type, struct file *file,
  			       const struct compat_iovec __user *uvector,
  			       unsigned long nr_segs, loff_t *pos)
  {

  	compat_ssize_t tot_len;
  	struct iovec iovstack[UIO_FASTIOV];

  	struct iovec *iov = iovstack;

  	ssize_t ret;

  	io_fn_t fn;
  	iov_fn_t fnv;

  	ret = -EINVAL;

  	if (!file->f_op)
  		goto out;

  	ret = -EFAULT;
  	if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
  		goto out;

  	tot_len = compat_rw_copy_check_uvector(type, uvector, nr_segs,
  					       UIO_FASTIOV, iovstack, &iov);

  	if (tot_len == 0) {
  		ret = 0;
  		goto out;
  	}
  
  	ret = rw_verify_area(type, file, pos, tot_len);

  	if (ret < 0)

  		goto out;
  
  	fnv = NULL;
  	if (type == READ) {
  		fn = file->f_op->read;

  		fnv = file->f_op->aio_read;

  	} else {
  		fn = (io_fn_t)file->f_op->write;

  		fnv = file->f_op->aio_write;

  	}

  	if (fnv)
  		ret = do_sync_readv_writev(file, iov, nr_segs, tot_len,
  						pos, fnv);
  	else
  		ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn);

  out:
  	if (iov != iovstack)
  		kfree(iov);

  	if ((ret + (type == READ)) > 0) {

  		if (type == READ)

  			fsnotify_access(file);

  		else

  			fsnotify_modify(file);

  	}

  	return ret;
  }

  static size_t compat_readv(struct file *file,
  			   const struct compat_iovec __user *vec,
  			   unsigned long vlen, loff_t *pos)

  {

  	ssize_t ret = -EBADF;

  	if (!(file->f_mode & FMODE_READ))
  		goto out;
  
  	ret = -EINVAL;

  	if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read))

  		goto out;

  	ret = compat_do_readv_writev(READ, file, vec, vlen, pos);

  
  out:

  	if (ret > 0)
  		add_rchar(current, ret);
  	inc_syscr(current);

  	return ret;
  }
  
  asmlinkage ssize_t
  compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec,
  		 unsigned long vlen)
  {
  	struct file *file;

  	int fput_needed;

  	ssize_t ret;

  	file = fget_light(fd, &fput_needed);

  	if (!file)
  		return -EBADF;
  	ret = compat_readv(file, vec, vlen, &file->f_pos);

  	fput_light(file, fput_needed);

  	return ret;
  }

  asmlinkage ssize_t
  compat_sys_preadv(unsigned long fd, const struct compat_iovec __user *vec,

  		  unsigned long vlen, u32 pos_low, u32 pos_high)

  {
  	loff_t pos = ((loff_t)pos_high << 32) | pos_low;
  	struct file *file;

  	int fput_needed;

  	ssize_t ret;
  
  	if (pos < 0)
  		return -EINVAL;

  	file = fget_light(fd, &fput_needed);

  	if (!file)
  		return -EBADF;

  	ret = -ESPIPE;
  	if (file->f_mode & FMODE_PREAD)
  		ret = compat_readv(file, vec, vlen, &pos);

  	fput_light(file, fput_needed);

  	return ret;
  }

  static size_t compat_writev(struct file *file,
  			    const struct compat_iovec __user *vec,
  			    unsigned long vlen, loff_t *pos)

  {

  	ssize_t ret = -EBADF;

  	if (!(file->f_mode & FMODE_WRITE))
  		goto out;
  
  	ret = -EINVAL;

  	if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write))

  		goto out;

  	ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos);

  
  out:

  	if (ret > 0)
  		add_wchar(current, ret);
  	inc_syscw(current);

  	return ret;
  }
  
  asmlinkage ssize_t
  compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec,
  		  unsigned long vlen)
  {
  	struct file *file;

  	int fput_needed;

  	ssize_t ret;

  	file = fget_light(fd, &fput_needed);

  	if (!file)
  		return -EBADF;
  	ret = compat_writev(file, vec, vlen, &file->f_pos);

  	fput_light(file, fput_needed);

  	return ret;
  }

  asmlinkage ssize_t
  compat_sys_pwritev(unsigned long fd, const struct compat_iovec __user *vec,

  		   unsigned long vlen, u32 pos_low, u32 pos_high)

  {
  	loff_t pos = ((loff_t)pos_high << 32) | pos_low;
  	struct file *file;

  	int fput_needed;

  	ssize_t ret;
  
  	if (pos < 0)
  		return -EINVAL;

  	file = fget_light(fd, &fput_needed);

  	if (!file)
  		return -EBADF;

  	ret = -ESPIPE;
  	if (file->f_mode & FMODE_PWRITE)
  		ret = compat_writev(file, vec, vlen, &pos);

  	fput_light(file, fput_needed);

  	return ret;
  }

  asmlinkage long
  compat_sys_vmsplice(int fd, const struct compat_iovec __user *iov32,
  		    unsigned int nr_segs, unsigned int flags)
  {
  	unsigned i;

  	struct iovec __user *iov;

  	if (nr_segs > UIO_MAXIOV)

  		return -EINVAL;
  	iov = compat_alloc_user_space(nr_segs * sizeof(struct iovec));
  	for (i = 0; i < nr_segs; i++) {
  		struct compat_iovec v;
  		if (get_user(v.iov_base, &iov32[i].iov_base) ||
  		    get_user(v.iov_len, &iov32[i].iov_len) ||
  		    put_user(compat_ptr(v.iov_base), &iov[i].iov_base) ||
  		    put_user(v.iov_len, &iov[i].iov_len))
  			return -EFAULT;
  	}
  	return sys_vmsplice(fd, iov, nr_segs, flags);
  }

  /*

   * Exactly like fs/open.c:sys_open(), except that it doesn't set the
   * O_LARGEFILE flag.
   */
  asmlinkage long
  compat_sys_open(const char __user *filename, int flags, int mode)
  {

  	return do_sys_open(AT_FDCWD, filename, flags, mode);
  }
  
  /*
   * Exactly like fs/open.c:sys_openat(), except that it doesn't set the
   * O_LARGEFILE flag.
   */
  asmlinkage long

  compat_sys_openat(unsigned int dfd, const char __user *filename, int flags, int mode)

  {
  	return do_sys_open(dfd, filename, flags, mode);

  }

  #define __COMPAT_NFDBITS       (8 * sizeof(compat_ulong_t))

  static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,
  				      int timeval, int ret)
  {
  	struct timespec ts;
  
  	if (!p)
  		return ret;
  
  	if (current->personality & STICKY_TIMEOUTS)
  		goto sticky;
  
  	/* No update for zero timeout */
  	if (!end_time->tv_sec && !end_time->tv_nsec)
  		return ret;
  
  	ktime_get_ts(&ts);
  	ts = timespec_sub(*end_time, ts);
  	if (ts.tv_sec < 0)
  		ts.tv_sec = ts.tv_nsec = 0;
  
  	if (timeval) {
  		struct compat_timeval rtv;
  
  		rtv.tv_sec = ts.tv_sec;
  		rtv.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
  
  		if (!copy_to_user(p, &rtv, sizeof(rtv)))
  			return ret;
  	} else {
  		struct compat_timespec rts;
  
  		rts.tv_sec = ts.tv_sec;
  		rts.tv_nsec = ts.tv_nsec;
  
  		if (!copy_to_user(p, &rts, sizeof(rts)))
  			return ret;
  	}
  	/*
  	 * If an application puts its timeval in read-only memory, we
  	 * don't want the Linux-specific update to the timeval to
  	 * cause a fault after the select has completed
  	 * successfully. However, because we're not updating the
  	 * timeval, we can't restart the system call.
  	 */
  
  sticky:
  	if (ret == -ERESTARTNOHAND)
  		ret = -EINTR;
  	return ret;
  }

  /*
   * Ooo, nasty.  We need here to frob 32-bit unsigned longs to
   * 64-bit unsigned longs.
   */

  static

  int compat_get_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
  			unsigned long *fdset)
  {

  	nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);

  	if (ufdset) {
  		unsigned long odd;
  
  		if (!access_ok(VERIFY_WRITE, ufdset, nr*sizeof(compat_ulong_t)))
  			return -EFAULT;
  
  		odd = nr & 1UL;
  		nr &= ~1UL;
  		while (nr) {
  			unsigned long h, l;

  			if (__get_user(l, ufdset) || __get_user(h, ufdset+1))
  				return -EFAULT;

  			ufdset += 2;
  			*fdset++ = h << 32 | l;
  			nr -= 2;
  		}

  		if (odd && __get_user(*fdset, ufdset))
  			return -EFAULT;

  	} else {
  		/* Tricky, must clear full unsigned long in the
  		 * kernel fdset at the end, this makes sure that
  		 * actually happens.
  		 */
  		memset(fdset, 0, ((nr + 1) & ~1)*sizeof(compat_ulong_t));
  	}
  	return 0;
  }

  static

  int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
  		      unsigned long *fdset)

  {
  	unsigned long odd;

  	nr = DIV_ROUND_UP(nr, __COMPAT_NFDBITS);

  
  	if (!ufdset)

  		return 0;

  
  	odd = nr & 1UL;
  	nr &= ~1UL;
  	while (nr) {
  		unsigned long h, l;
  		l = *fdset++;
  		h = l >> 32;

  		if (__put_user(l, ufdset) || __put_user(h, ufdset+1))
  			return -EFAULT;

  		ufdset += 2;
  		nr -= 2;
  	}

  	if (odd && __put_user(*fdset, ufdset))
  		return -EFAULT;
  	return 0;

  }
  
  
  /*
   * This is a virtual copy of sys_select from fs/select.c and probably
   * should be compared to it from time to time
   */

  
  /*
   * We can actually return ERESTARTSYS instead of EINTR, but I'd
   * like to be certain this leads to no problems. So I return
   * EINTR just for safety.
   *
   * Update: ERESTARTSYS breaks at least the xview clock binary, so
   * I'm trying ERESTARTNOHAND which restart only when you want to.
   */

  int compat_core_sys_select(int n, compat_ulong_t __user *inp,

  	compat_ulong_t __user *outp, compat_ulong_t __user *exp,
  	struct timespec *end_time)

  {
  	fd_set_bits fds;

  	void *bits;

  	int size, max_fds, ret = -EINVAL;

  	struct fdtable *fdt;

  	long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];

  	if (n < 0)
  		goto out_nofds;

  	/* max_fds can increase, so grab it once to avoid race */

  	rcu_read_lock();

  	fdt = files_fdtable(current->files);

  	max_fds = fdt->max_fds;

  	rcu_read_unlock();

  	if (n > max_fds)
  		n = max_fds;

  
  	/*
  	 * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
  	 * since we used fdset we need to allocate memory in units of
  	 * long-words.
  	 */

  	size = FDS_BYTES(n);

  	bits = stack_fds;
  	if (size > sizeof(stack_fds) / 6) {
  		bits = kmalloc(6 * size, GFP_KERNEL);
  		ret = -ENOMEM;
  		if (!bits)
  			goto out_nofds;
  	}

  	fds.in      = (unsigned long *)  bits;
  	fds.out     = (unsigned long *) (bits +   size);
  	fds.ex      = (unsigned long *) (bits + 2*size);
  	fds.res_in  = (unsigned long *) (bits + 3*size);
  	fds.res_out = (unsigned long *) (bits + 4*size);
  	fds.res_ex  = (unsigned long *) (bits + 5*size);
  
  	if ((ret = compat_get_fd_set(n, inp, fds.in)) ||
  	    (ret = compat_get_fd_set(n, outp, fds.out)) ||
  	    (ret = compat_get_fd_set(n, exp, fds.ex)))
  		goto out;
  	zero_fd_set(n, fds.res_in);
  	zero_fd_set(n, fds.res_out);
  	zero_fd_set(n, fds.res_ex);

  	ret = do_select(n, &fds, end_time);

  
  	if (ret < 0)
  		goto out;
  	if (!ret) {
  		ret = -ERESTARTNOHAND;
  		if (signal_pending(current))
  			goto out;
  		ret = 0;
  	}

  	if (compat_set_fd_set(n, inp, fds.res_in) ||
  	    compat_set_fd_set(n, outp, fds.res_out) ||
  	    compat_set_fd_set(n, exp, fds.res_ex))
  		ret = -EFAULT;

  out:

  	if (bits != stack_fds)
  		kfree(bits);

  out_nofds:
  	return ret;
  }

  asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp,
  	compat_ulong_t __user *outp, compat_ulong_t __user *exp,
  	struct compat_timeval __user *tvp)
  {

  	struct timespec end_time, *to = NULL;

  	struct compat_timeval tv;
  	int ret;
  
  	if (tvp) {
  		if (copy_from_user(&tv, tvp, sizeof(tv)))
  			return -EFAULT;

  		to = &end_time;

  		if (poll_select_set_timeout(to,
  				tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
  				(tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))

  			return -EINVAL;

  	}

  	ret = compat_core_sys_select(n, inp, outp, exp, to);
  	ret = poll_select_copy_remaining(&end_time, tvp, 1, ret);

  
  	return ret;
  }

  struct compat_sel_arg_struct {
  	compat_ulong_t n;
  	compat_uptr_t inp;
  	compat_uptr_t outp;
  	compat_uptr_t exp;
  	compat_uptr_t tvp;
  };
  
  asmlinkage long compat_sys_old_select(struct compat_sel_arg_struct __user *arg)
  {
  	struct compat_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));
  }

  #ifdef HAVE_SET_RESTORE_SIGMASK

  static long do_compat_pselect(int n, compat_ulong_t __user *inp,

  	compat_ulong_t __user *outp, compat_ulong_t __user *exp,
  	struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask,
  	compat_size_t sigsetsize)
  {
  	compat_sigset_t ss32;
  	sigset_t ksigmask, sigsaved;

  	struct compat_timespec ts;

  	struct timespec end_time, *to = NULL;

  	int ret;
  
  	if (tsp) {
  		if (copy_from_user(&ts, tsp, sizeof(ts)))
  			return -EFAULT;

  		to = &end_time;
  		if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))

  			return -EINVAL;
  	}
  
  	if (sigmask) {
  		if (sigsetsize != sizeof(compat_sigset_t))
  			return -EINVAL;
  		if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
  			return -EFAULT;
  		sigset_from_compat(&ksigmask, &ss32);
  
  		sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
  		sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
  	}

  	ret = compat_core_sys_select(n, inp, outp, exp, to);
  	ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);

  
  	if (ret == -ERESTARTNOHAND) {
  		/*
  		 * Don't restore the signal mask yet. Let do_signal() deliver
  		 * the signal on the way back to userspace, before the signal
  		 * mask is restored.
  		 */
  		if (sigmask) {
  			memcpy(&current->saved_sigmask, &sigsaved,
  					sizeof(sigsaved));

  			set_restore_sigmask();

  		}
  	} else if (sigmask)
  		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
  
  	return ret;
  }
  
  asmlinkage long compat_sys_pselect6(int n, compat_ulong_t __user *inp,
  	compat_ulong_t __user *outp, compat_ulong_t __user *exp,
  	struct compat_timespec __user *tsp, void __user *sig)
  {
  	compat_size_t sigsetsize = 0;
  	compat_uptr_t up = 0;
  
  	if (sig) {
  		if (!access_ok(VERIFY_READ, sig,
  				sizeof(compat_uptr_t)+sizeof(compat_size_t)) ||
  		    	__get_user(up, (compat_uptr_t __user *)sig) ||
  		    	__get_user(sigsetsize,
  				(compat_size_t __user *)(sig+sizeof(up))))
  			return -EFAULT;
  	}

  	return do_compat_pselect(n, inp, outp, exp, tsp, compat_ptr(up),
  				 sigsetsize);

  }
  
  asmlinkage long compat_sys_ppoll(struct pollfd __user *ufds,
  	unsigned int nfds, struct compat_timespec __user *tsp,
  	const compat_sigset_t __user *sigmask, compat_size_t sigsetsize)
  {
  	compat_sigset_t ss32;
  	sigset_t ksigmask, sigsaved;
  	struct compat_timespec ts;

  	struct timespec end_time, *to = NULL;

  	int ret;
  
  	if (tsp) {
  		if (copy_from_user(&ts, tsp, sizeof(ts)))
  			return -EFAULT;

  		to = &end_time;
  		if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
  			return -EINVAL;

  	}
  
  	if (sigmask) {

  		if (sigsetsize != sizeof(compat_sigset_t))

  			return -EINVAL;
  		if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
  			return -EFAULT;
  		sigset_from_compat(&ksigmask, &ss32);
  
  		sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
  		sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
  	}

  	ret = do_sys_poll(ufds, nfds, to);

  
  	/* We can restart this syscall, usually */
  	if (ret == -EINTR) {
  		/*
  		 * Don't restore the signal mask yet. Let do_signal() deliver
  		 * the signal on the way back to userspace, before the signal
  		 * mask is restored.
  		 */
  		if (sigmask) {
  			memcpy(&current->saved_sigmask, &sigsaved,
  				sizeof(sigsaved));

  			set_restore_sigmask();

  		}
  		ret = -ERESTARTNOHAND;
  	} else if (sigmask)
  		sigprocmask(SIG_SETMASK, &sigsaved, NULL);

  	ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);

  
  	return ret;
  }

  #endif /* HAVE_SET_RESTORE_SIGMASK */

  #ifdef CONFIG_EPOLL

  #ifdef HAVE_SET_RESTORE_SIGMASK

  asmlinkage long compat_sys_epoll_pwait(int epfd,
  			struct compat_epoll_event __user *events,
  			int maxevents, int timeout,
  			const compat_sigset_t __user *sigmask,
  			compat_size_t sigsetsize)
  {
  	long err;
  	compat_sigset_t csigmask;
  	sigset_t ksigmask, sigsaved;
  
  	/*
  	 * If the caller wants a certain signal mask to be set during the wait,
  	 * we apply it here.
  	 */
  	if (sigmask) {
  		if (sigsetsize != sizeof(compat_sigset_t))
  			return -EINVAL;
  		if (copy_from_user(&csigmask, sigmask, sizeof(csigmask)))
  			return -EFAULT;
  		sigset_from_compat(&ksigmask, &csigmask);
  		sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
  		sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
  	}

  	err = sys_epoll_wait(epfd, events, maxevents, timeout);

  
  	/*
  	 * If we changed the signal mask, we need to restore the original one.
  	 * In case we've got a signal while waiting, we do not restore the
  	 * signal mask yet, and we allow do_signal() to deliver the signal on
  	 * the way back to userspace, before the signal mask is restored.
  	 */
  	if (sigmask) {
  		if (err == -EINTR) {
  			memcpy(&current->saved_sigmask, &sigsaved,
  			       sizeof(sigsaved));

  			set_restore_sigmask();

  		} else
  			sigprocmask(SIG_SETMASK, &sigsaved, NULL);
  	}
  
  	return err;
  }

  #endif /* HAVE_SET_RESTORE_SIGMASK */

  
  #endif /* CONFIG_EPOLL */

  
  #ifdef CONFIG_SIGNALFD

  asmlinkage long compat_sys_signalfd4(int ufd,
  				     const compat_sigset_t __user *sigmask,
  				     compat_size_t sigsetsize, int flags)

  {
  	compat_sigset_t ss32;
  	sigset_t tmp;
  	sigset_t __user *ksigmask;
  
  	if (sigsetsize != sizeof(compat_sigset_t))
  		return -EINVAL;
  	if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
  		return -EFAULT;
  	sigset_from_compat(&tmp, &ss32);
  	ksigmask = compat_alloc_user_space(sizeof(sigset_t));
  	if (copy_to_user(ksigmask, &tmp, sizeof(sigset_t)))
  		return -EFAULT;

  	return sys_signalfd4(ufd, ksigmask, sizeof(sigset_t), flags);

  }

  asmlinkage long compat_sys_signalfd(int ufd,
  				    const compat_sigset_t __user *sigmask,
  				    compat_size_t sigsetsize)
  {
  	return compat_sys_signalfd4(ufd, sigmask, sigsetsize, 0);
  }

  #endif /* CONFIG_SIGNALFD */

  #ifdef CONFIG_TIMERFD

  asmlinkage long compat_sys_timerfd_settime(int ufd, int flags,
  				   const struct compat_itimerspec __user *utmr,
  				   struct compat_itimerspec __user *otmr)

  {

  	int error;

  	struct itimerspec t;
  	struct itimerspec __user *ut;

  	if (get_compat_itimerspec(&t, utmr))

  		return -EFAULT;

  	ut = compat_alloc_user_space(2 * sizeof(struct itimerspec));
  	if (copy_to_user(&ut[0], &t, sizeof(t)))

  		return -EFAULT;

  	error = sys_timerfd_settime(ufd, flags, &ut[0], &ut[1]);
  	if (!error && otmr)
  		error = (copy_from_user(&t, &ut[1], sizeof(struct itimerspec)) ||
  			 put_compat_itimerspec(otmr, &t)) ? -EFAULT: 0;
  
  	return error;
  }
  
  asmlinkage long compat_sys_timerfd_gettime(int ufd,
  				   struct compat_itimerspec __user *otmr)
  {
  	int error;
  	struct itimerspec t;
  	struct itimerspec __user *ut;

  	ut = compat_alloc_user_space(sizeof(struct itimerspec));
  	error = sys_timerfd_gettime(ufd, ut);
  	if (!error)
  		error = (copy_from_user(&t, ut, sizeof(struct itimerspec)) ||
  			 put_compat_itimerspec(otmr, &t)) ? -EFAULT: 0;
  
  	return error;

  }
  
  #endif /* CONFIG_TIMERFD */

  
  #ifdef CONFIG_FHANDLE
  /*
   * Exactly like fs/open.c:sys_open_by_handle_at(), except that it
   * doesn't set the O_LARGEFILE flag.
   */
  asmlinkage long
  compat_sys_open_by_handle_at(int mountdirfd,
  			     struct file_handle __user *handle, int flags)
  {
  	return do_handle_open(mountdirfd, handle, flags);
  }
  #endif