static long ocfs2_fallocate(struct file *file, int mode, loff_t offset,
			    loff_t len)
{
	struct inode *inode = file_inode(file);
	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	struct ocfs2_space_resv sr;
	int change_size = 1;
	int cmd = OCFS2_IOC_RESVSP64;

	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
		return -EOPNOTSUPP;
	if (!ocfs2_writes_unwritten_extents(osb))
		return -EOPNOTSUPP;

	if (mode & FALLOC_FL_KEEP_SIZE)
		change_size = 0;

	if (mode & FALLOC_FL_PUNCH_HOLE)
		cmd = OCFS2_IOC_UNRESVSP64;

	sr.l_whence = 0;
	sr.l_start = (s64)offset;
	sr.l_len = (s64)len;

	return __ocfs2_change_file_space(NULL, inode, offset, cmd, &sr,
					 change_size);
}

Unknown