ocfs2_blocks_for_bytes
past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
v_blkno = ocfs2_blocks_for_bytes(sb, i_size_read(dir));
start_block = ocfs2_blocks_for_bytes(sb, start);
end_block = ocfs2_blocks_for_bytes(sb, end);
num_blocks = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
blocks = ocfs2_blocks_for_bytes(sb, bytes);
blocks = ocfs2_blocks_for_bytes(si->si_inode->i_sb, bytes);