lfs_blkstofrags
maxfsblock = lfs_blkstofrags(fs, lfs_sb_getsize(fs));
lfs_dino_getblocks(fs, dip) + lfs_blkstofrags(fs, ifibc));
lfs_blkstofrags(fs, lfs_sb_getcleansz(fs) + lfs_sb_getsegtabsz(fs) + 1), fs);