efs_bmap
bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
extern int efs_bmap(struct inode *, int);
bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
bh = sb_bread(inode->i_sb, efs_bmap(inode, 0));
bh = sb_bread(inode->i_sb, efs_bmap(inode, 1));