clrblock
clrblock(&sblock, cg_blksfree(&acg),
clrblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag);
clrblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag);
static void clrblock(struct fs *, unsigned char *, int);
clrblock(&sblock, cg_blksfree(&acg), blkno);
void clrblock(struct fs *, unsigned char *, int);
clrblock(&sblock, cg_blksfree(&acg), blkno);