/*
   *  linux/fs/hpfs/dir.c
   *
   *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   *
   *  directory VFS functions
   */
  
  #include "hpfs_fn.h"
  
  static int hpfs_dir_release(struct inode *inode, struct file *filp)
  {
  	lock_kernel();
  	hpfs_del_pos(inode, &filp->f_pos);
  	/*hpfs_write_if_changed(inode);*/
  	unlock_kernel();
  	return 0;
  }
  
  /* This is slow, but it's not used often */
  
  static loff_t hpfs_dir_lseek(struct file *filp, loff_t off, int whence)
  {
  	loff_t new_off = off + (whence == 1 ? filp->f_pos : 0);
  	loff_t pos;
  	struct quad_buffer_head qbh;

  	struct inode *i = filp->f_path.dentry->d_inode;

  	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
  	struct super_block *s = i->i_sb;
  
  	lock_kernel();
  
  	/*printk("dir lseek
  ");*/
  	if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;

  	mutex_lock(&i->i_mutex);

  	pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
  	while (pos != new_off) {
  		if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
  		else goto fail;
  		if (pos == 12) goto fail;
  	}

  	mutex_unlock(&i->i_mutex);

  ok:
  	unlock_kernel();
  	return filp->f_pos = new_off;
  fail:

  	mutex_unlock(&i->i_mutex);

  	/*printk("illegal lseek: %016llx
  ", new_off);*/
  	unlock_kernel();
  	return -ESPIPE;
  }
  
  static int hpfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
  {

  	struct inode *inode = filp->f_path.dentry->d_inode;

  	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
  	struct quad_buffer_head qbh;
  	struct hpfs_dirent *de;
  	int lc;
  	long old_pos;
  	char *tempname;
  	int c1, c2 = 0;
  	int ret = 0;
  
  	lock_kernel();
  
  	if (hpfs_sb(inode->i_sb)->sb_chk) {
  		if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
  			ret = -EFSERROR;
  			goto out;
  		}
  		if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
  			ret = -EFSERROR;
  			goto out;
  		}
  	}
  	if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
  		struct buffer_head *bh;
  		struct fnode *fno;
  		int e = 0;
  		if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
  			ret = -EIOERROR;
  			goto out;
  		}
  		if (!fno->dirflag) {
  			e = 1;

  			hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
  					(unsigned long)inode->i_ino);

  		}
  		if (hpfs_inode->i_dno != fno->u.external[0].disk_secno) {
  			e = 1;
  			hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, fno->u.external[0].disk_secno);
  		}
  		brelse(bh);
  		if (e) {
  			ret = -EFSERROR;
  			goto out;
  		}
  	}
  	lc = hpfs_sb(inode->i_sb)->sb_lowercase;
  	if (filp->f_pos == 12) { /* diff -r requires this (note, that diff -r */
  		filp->f_pos = 13; /* also fails on msdos filesystem in 2.0) */
  		goto out;
  	}
  	if (filp->f_pos == 13) {
  		ret = -ENOENT;
  		goto out;
  	}
  	
  	while (1) {
  		again:
  		/* This won't work when cycle is longer than number of dirents
  		   accepted by filldir, but what can I do?
  		   maybe killall -9 ls helps */
  		if (hpfs_sb(inode->i_sb)->sb_chk)
  			if (hpfs_stop_cycles(inode->i_sb, filp->f_pos, &c1, &c2, "hpfs_readdir")) {
  				ret = -EFSERROR;
  				goto out;
  			}
  		if (filp->f_pos == 12)
  			goto out;
  		if (filp->f_pos == 3 || filp->f_pos == 4 || filp->f_pos == 5) {
  			printk("HPFS: warning: pos==%d
  ",(int)filp->f_pos);
  			goto out;
  		}
  		if (filp->f_pos == 0) {
  			if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0)
  				goto out;
  			filp->f_pos = 11;
  		}
  		if (filp->f_pos == 11) {
  			if (filldir(dirent, "..", 2, filp->f_pos, hpfs_inode->i_parent_dir, DT_DIR) < 0)
  				goto out;
  			filp->f_pos = 1;
  		}
  		if (filp->f_pos == 1) {
  			filp->f_pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
  			hpfs_add_pos(inode, &filp->f_pos);
  			filp->f_version = inode->i_version;
  		}
  		old_pos = filp->f_pos;
  		if (!(de = map_pos_dirent(inode, &filp->f_pos, &qbh))) {
  			ret = -EIOERROR;
  			goto out;
  		}
  		if (de->first || de->last) {
  			if (hpfs_sb(inode->i_sb)->sb_chk) {

  				if (de->first && !de->last && (de->namelen != 2
  				    || de ->name[0] != 1 || de->name[1] != 1))
  					hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", old_pos);
  				if (de->last && (de->namelen != 1 || de ->name[0] != 255))
  					hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", old_pos);

  			}
  			hpfs_brelse4(&qbh);
  			goto again;
  		}
  		tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
  		if (filldir(dirent, tempname, de->namelen, old_pos, de->fnode, DT_UNKNOWN) < 0) {
  			filp->f_pos = old_pos;
  			if (tempname != (char *)de->name) kfree(tempname);
  			hpfs_brelse4(&qbh);
  			goto out;
  		}
  		if (tempname != (char *)de->name) kfree(tempname);
  		hpfs_brelse4(&qbh);
  	}
  out:
  	unlock_kernel();
  	return ret;
  }
  
  /*
   * lookup.  Search the specified directory for the specified name, set
   * *result to the corresponding inode.
   *
   * lookup uses the inode number to tell read_inode whether it is reading
   * the inode of a directory or a file -- file ino's are odd, directory
   * ino's are even.  read_inode avoids i/o for file inodes; everything
   * needed is up here in the directory.  (And file fnodes are out in
   * the boondocks.)
   *
   *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
   *	      inode numbers are just fnode sector numbers; iget lock is used
   *	      to tell read_inode to read fnode or not.
   */
  
  struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
  {
  	const char *name = dentry->d_name.name;
  	unsigned len = dentry->d_name.len;
  	struct quad_buffer_head qbh;
  	struct hpfs_dirent *de;
  	ino_t ino;
  	int err;
  	struct inode *result = NULL;
  	struct hpfs_inode_info *hpfs_result;
  
  	lock_kernel();
  	if ((err = hpfs_chk_name((char *)name, &len))) {
  		if (err == -ENAMETOOLONG) {
  			unlock_kernel();
  			return ERR_PTR(-ENAMETOOLONG);
  		}
  		goto end_add;
  	}
  
  	/*
  	 * '.' and '..' will never be passed here.
  	 */
  
  	de = map_dirent(dir, hpfs_i(dir)->i_dno, (char *) name, len, NULL, &qbh);
  
  	/*
  	 * This is not really a bailout, just means file not found.
  	 */
  
  	if (!de) goto end;
  
  	/*
  	 * Get inode number, what we're after.
  	 */
  
  	ino = de->fnode;
  
  	/*
  	 * Go find or make an inode.
  	 */
  
  	result = iget_locked(dir->i_sb, ino);
  	if (!result) {
  		hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
  		goto bail1;
  	}
  	if (result->i_state & I_NEW) {
  		hpfs_init_inode(result);
  		if (de->directory)
  			hpfs_read_inode(result);
  		else if (de->ea_size && hpfs_sb(dir->i_sb)->sb_eas)
  			hpfs_read_inode(result);
  		else {
  			result->i_mode |= S_IFREG;
  			result->i_mode &= ~0111;
  			result->i_op = &hpfs_file_iops;
  			result->i_fop = &hpfs_file_ops;
  			result->i_nlink = 1;
  		}
  		unlock_new_inode(result);
  	}
  	hpfs_result = hpfs_i(result);
  	if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
  
  	hpfs_decide_conv(result, (char *)name, len);
  
  	if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
  		hpfs_error(result->i_sb, "ACLs or XPERM found. This is probably HPFS386. This driver doesn't support it now. Send me some info on these structures");
  		goto bail1;
  	}
  
  	/*
  	 * Fill in the info from the directory if this is a newly created
  	 * inode.
  	 */
  
  	if (!result->i_ctime.tv_sec) {
  		if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, de->creation_date)))
  			result->i_ctime.tv_sec = 1;
  		result->i_ctime.tv_nsec = 0;
  		result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, de->write_date);
  		result->i_mtime.tv_nsec = 0;
  		result->i_atime.tv_sec = local_to_gmt(dir->i_sb, de->read_date);
  		result->i_atime.tv_nsec = 0;
  		hpfs_result->i_ea_size = de->ea_size;
  		if (!hpfs_result->i_ea_mode && de->read_only)
  			result->i_mode &= ~0222;
  		if (!de->directory) {
  			if (result->i_size == -1) {
  				result->i_size = de->file_size;
  				result->i_data.a_ops = &hpfs_aops;
  				hpfs_i(result)->mmu_private = result->i_size;
  			/*
  			 * i_blocks should count the fnode and any anodes.
  			 * We count 1 for the fnode and don't bother about
  			 * anodes -- the disk heads are on the directory band
  			 * and we want them to stay there.
  			 */
  				result->i_blocks = 1 + ((result->i_size + 511) >> 9);
  			}
  		}
  	}
  
  	hpfs_brelse4(&qbh);
  
  	/*
  	 * Made it.
  	 */
  
  	end:
  	end_add:
  	hpfs_set_dentry_operations(dentry);
  	unlock_kernel();
  	d_add(dentry, result);
  	return NULL;
  
  	/*
  	 * Didn't.
  	 */
  	bail1:
  	
  	hpfs_brelse4(&qbh);
  	
  	/*bail:*/
  
  	unlock_kernel();
  	return ERR_PTR(-ENOENT);
  }

  const struct file_operations hpfs_dir_ops =

  {
  	.llseek		= hpfs_dir_lseek,
  	.read		= generic_read_dir,
  	.readdir	= hpfs_readdir,
  	.release	= hpfs_dir_release,
  	.fsync		= hpfs_file_fsync,
  };