Example #1
0
/**
 * alloc_file - allocate and initialize a 'struct file'
 * @mnt: the vfsmount on which the file will reside
 * @dentry: the dentry representing the new file
 * @mode: the mode with which the new file will be opened
 * @fop: the 'struct file_operations' for the new file
 *
 * Use this instead of get_empty_filp() to get a new
 * 'struct file'.  Do so because of the same initialization
 * pitfalls reasons listed for init_file().  This is a
 * preferred interface to using init_file().
 *
 * If all the callers of init_file() are eliminated, its
 * code should be moved into this function.
 */
struct file *alloc_file(struct path *path, fmode_t mode,
		const struct file_operations *fop)
{
	struct file *file;

	file = get_empty_filp();
	if (!file)
		return NULL;

	file->f_path = *path;
	file->f_mapping = path->dentry->d_inode->i_mapping;
	file->f_mode = mode;
	file->f_op = fop;

	/*
	 * These mounts don't really matter in practice
	 * for r/o bind mounts.  They aren't userspace-
	 * visible.  We do this for consistency, and so
	 * that we can do debugging checks at __fput()
	 */
	if ((mode & FMODE_WRITE) && !special_file(path->dentry->d_inode->i_mode)) {
		file_take_write(file);
		WARN_ON(mnt_clone_write(path->mnt));
	}
	if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
		i_readcount_inc(path->dentry->d_inode);
	return file;
}
struct file *alloc_file(struct path *path, fmode_t mode,
		const struct file_operations *fop)
{
	struct file *file;

	file = get_empty_filp();
	if (!file)
		return NULL;

	file->f_path = *path;
	file->f_mapping = path->dentry->d_inode->i_mapping;
	file->f_mode = mode;
	file->f_op = fop;

	/*
                                                
                                                
                                                
                                               
  */
	if ((mode & FMODE_WRITE) && !special_file(path->dentry->d_inode->i_mode)) {
		file_take_write(file);
		WARN_ON(mnt_clone_write(path->mnt));
	}
	if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
		i_readcount_inc(path->dentry->d_inode);
	return file;
}