/* * Write a superblock and associated information back to disk. */ int ext2fs_sbupdate(struct ufsmount *mp, int waitfor) { struct m_ext2fs *fs = mp->um_e2fs; struct buf *bp; int error = 0; bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0); e2fs_sbsave(&fs->e2fs, (struct ext2fs *) bp->b_data); if (waitfor == MNT_WAIT) error = bwrite(bp); else bawrite(bp); return (error); }
/* * Write a superblock and associated information back to disk. */ int ext2fs_sbupdate(struct ufsmount *mp, int waitfor) { printf("In file: %s, fun: %s,lineno: %d\n",__FILE__, __func__, __LINE__); struct m_ext2fs *fs = mp->um_e2fs; struct buf *bp; int error = 0; bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0); e2fs_sbsave(&fs->e2fs, (struct ext2fs*)bp->b_data); if (waitfor == MNT_WAIT) error = bwrite(bp); else bawrite(bp); return (error); }
/* * Initialize a cylinder (block) group. */ void initcg(uint cylno) { uint nblcg, i, j, sboff; struct ext2fs_dinode *dp; /* * Make a copy of the superblock and group descriptors. */ if (sblock.e2fs.e2fs_rev == E2FS_REV0 || (sblock.e2fs.e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) == 0 || cg_has_sb(cylno)) { sblock.e2fs.e2fs_block_group_nr = cylno; sboff = 0; if (cgbase(&sblock, cylno) == 0) { /* preserve data in bootblock in cg0 */ sboff = SBOFF; } e2fs_sbsave(&sblock.e2fs, (struct ext2fs *)(iobuf + sboff)); e2fs_cgsave(gd, (struct ext2_gd *)(iobuf + sblock.e2fs_bsize * NBLOCK_SUPERBLOCK), sizeof(struct ext2_gd) * sblock.e2fs_ncg); /* write superblock and group descriptor backups */ wtfs(fsbtodb(&sblock, cgbase(&sblock, cylno)) + sboff / sectorsize, iobufsize - sboff, iobuf + sboff); } /* * Initialize block bitmap. */ memset(buf, 0, sblock.e2fs_bsize); if (cylno == (sblock.e2fs_ncg - 1)) { /* The last group could have less blocks than e2fs_bpg. */ nblcg = sblock.e2fs.e2fs_bcount - cgbase(&sblock, sblock.e2fs_ncg - 1); for (i = nblcg; i < roundup(nblcg, NBBY); i++) setbit(buf, i); memset(&buf[i / NBBY], ~0U, sblock.e2fs.e2fs_bpg - i); } /* set overhead (superblock, group descriptor etc.) blocks used */ for (i = 0; i < cgoverhead(cylno) / NBBY; i++) buf[i] = ~0; i = i * NBBY; for (; i < cgoverhead(cylno); i++) setbit(buf, i); wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_b_bitmap), sblock.e2fs_bsize, buf); /* * Initialize inode bitmap. * * Assume e2fs_ipg is a multiple of NBBY since * it's a multiple of e2fs_ipb (as we did above). * Note even (possibly smaller) the last group has the same e2fs_ipg. */ assert(!(sblock.e2fs.e2fs_ipg % NBBY)); i = sblock.e2fs.e2fs_ipg / NBBY; memset(buf, 0, i); assert(sblock.e2fs_bsize >= i); memset(buf + i, ~0U, sblock.e2fs_bsize - i); if (cylno == 0) { /* mark reserved inodes */ for (i = 1; i < EXT2_FIRSTINO; i++) setbit(buf, EXT2_INO_INDEX(i)); } wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_i_bitmap), sblock.e2fs_bsize, buf); /* * Initialize inode tables. * * Just initialize generation numbers for NFS security. * XXX: sys/ufs/ext2fs/ext2fs_alloc.c:ext2fs_valloc() seems * to override these generated numbers. */ memset(buf, 0, sblock.e2fs_bsize); for (i = 0; i < sblock.e2fs_itpg; i++) { for (j = 0; j < sblock.e2fs_ipb; j++) { dp = (struct ext2fs_dinode *)(buf + inodesize * j); /* h2fs32() just for consistency */ dp->e2di_gen = h2fs32(arc4random()); } wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_i_tables + i), sblock.e2fs_bsize, buf); } }
void mke2fs(const char *fsys, int fi, int fo) { struct timeval tv; int64_t minfssize; uint bcount, fbcount, ficount; uint blocks_gd, blocks_per_cg, inodes_per_cg, iblocks_per_cg; uint minblocks_per_cg, blocks_lastcg; uint ncg, cylno, sboff; uuid_t uuid; uint32_t uustat; int i, len, col, delta, fld_width, max_cols; struct winsize winsize; gettimeofday(&tv, NULL); fsi = fi; fso = fo; /* * collect and verify the block and fragment sizes */ if (!powerof2(bsize)) { errx(EXIT_FAILURE, "block size must be a power of 2, not %u\n", bsize); } if (!powerof2(fsize)) { errx(EXIT_FAILURE, "fragment size must be a power of 2, not %u\n", fsize); } if (fsize < sectorsize) { errx(EXIT_FAILURE, "fragment size %u is too small, minimum is %u\n", fsize, sectorsize); } if (bsize < MINBSIZE) { errx(EXIT_FAILURE, "block size %u is too small, minimum is %u\n", bsize, MINBSIZE); } if (bsize > EXT2_MAXBSIZE) { errx(EXIT_FAILURE, "block size %u is too large, maximum is %u\n", bsize, MAXBSIZE); } if (bsize != fsize) { /* * There is no fragment support on current ext2fs (yet?), * but some kernel code refers fsize or fpg as bsize or bpg * and Linux seems to set the same values to them. */ errx(EXIT_FAILURE, "block size (%u) can't be different from " "fragment size (%u)\n", bsize, fsize); } /* variable inodesize is REV1 feature */ if (Oflag == 0 && inodesize != EXT2_REV0_DINODE_SIZE) { errx(EXIT_FAILURE, "GOOD_OLD_REV file system format" " doesn't support %d byte inode\n", inodesize); } sblock.e2fs.e2fs_log_bsize = ilog2(bsize) - LOG_MINBSIZE; /* Umm, why not e2fs_log_fsize? */ sblock.e2fs.e2fs_fsize = ilog2(fsize) - LOG_MINBSIZE; sblock.e2fs_bsize = bsize; sblock.e2fs_bshift = sblock.e2fs.e2fs_log_bsize + LOG_MINBSIZE; sblock.e2fs_qbmask = sblock.e2fs_bsize - 1; sblock.e2fs_bmask = ~sblock.e2fs_qbmask; sblock.e2fs_fsbtodb = ilog2(sblock.e2fs_bsize) - ilog2(sectorsize); sblock.e2fs_ipb = sblock.e2fs_bsize / inodesize; /* * Ext2fs preserves BBSIZE (1024 bytes) space at the top for * bootloader (though it is not enough at all for our bootloader). * If bsize == BBSIZE we have to preserve one block. * If bsize > BBSIZE, the first block already contains BBSIZE space * before superblock because superblock is allocated at SBOFF and * bsize is a power of two (i.e. 2048 bytes or more). */ sblock.e2fs.e2fs_first_dblock = (sblock.e2fs_bsize > BBSIZE) ? 0 : 1; minfssize = fsbtodb(&sblock, sblock.e2fs.e2fs_first_dblock + NBLOCK_SUPERBLOCK + 1 /* at least one group descriptor */ + NBLOCK_BLOCK_BITMAP + NBLOCK_INODE_BITMAP + 1 /* at least one inode table block */ + 1 /* at least one data block for rootdir */ + 1 /* at least one data block for data */ ); /* XXX and more? */ if (fssize < minfssize) errx(EXIT_FAILURE, "Filesystem size %" PRId64 " < minimum size of %" PRId64 "\n", fssize, minfssize); bcount = dbtofsb(&sblock, fssize); /* * While many people claim that ext2fs is a (bad) clone of ufs/ffs, * it isn't actual ffs so maybe we should call it "block group" * as their native name rather than ffs derived "cylinder group." * But we'll use the latter here since other kernel sources use it. * (I also agree "cylinder" based allocation is obsolete though) */ /* maybe "simple is the best" */ blocks_per_cg = sblock.e2fs_bsize * NBBY; ncg = howmany(bcount - sblock.e2fs.e2fs_first_dblock, blocks_per_cg); blocks_gd = howmany(sizeof(struct ext2_gd) * ncg, bsize); /* check range of inode number */ if (num_inodes < EXT2_FIRSTINO) num_inodes = EXT2_FIRSTINO; /* needs reserved inodes + 1 */ if (num_inodes > UINT16_MAX * ncg) num_inodes = UINT16_MAX * ncg; /* ext2bgd_nifree is uint16_t */ inodes_per_cg = num_inodes / ncg; iblocks_per_cg = howmany(inodesize * inodes_per_cg, bsize); /* Check that the last cylinder group has enough space for inodes */ minblocks_per_cg = NBLOCK_BLOCK_BITMAP + NBLOCK_INODE_BITMAP + iblocks_per_cg + 1; /* at least one data block */ if (Oflag == 0 || cg_has_sb(ncg - 1) != 0) minblocks_per_cg += NBLOCK_SUPERBLOCK + blocks_gd; blocks_lastcg = bcount - sblock.e2fs.e2fs_first_dblock - blocks_per_cg * (ncg - 1); if (blocks_lastcg < minblocks_per_cg) { /* * Since we make all the cylinder groups the same size, the * last will only be small if there are more than one * cylinder groups. If the last one is too small to store * filesystem data, just kill it. * * XXX: Does fsck_ext2fs(8) properly handle this case? */ bcount -= blocks_lastcg; ncg--; blocks_lastcg = blocks_per_cg; blocks_gd = howmany(sizeof(struct ext2_gd) * ncg, bsize); inodes_per_cg = num_inodes / ncg; } /* roundup inodes_per_cg to make it use whole inode table blocks */ inodes_per_cg = roundup(inodes_per_cg, sblock.e2fs_ipb); num_inodes = inodes_per_cg * ncg; iblocks_per_cg = inodes_per_cg / sblock.e2fs_ipb; /* XXX: probably we should check these adjusted values again */ sblock.e2fs.e2fs_bcount = bcount; sblock.e2fs.e2fs_icount = num_inodes; sblock.e2fs_ncg = ncg; sblock.e2fs_ngdb = blocks_gd; sblock.e2fs_itpg = iblocks_per_cg; sblock.e2fs.e2fs_rbcount = sblock.e2fs.e2fs_bcount * minfree / 100; /* e2fs_fbcount will be accounted later */ /* e2fs_ficount will be accounted later */ sblock.e2fs.e2fs_bpg = blocks_per_cg; sblock.e2fs.e2fs_fpg = blocks_per_cg; sblock.e2fs.e2fs_ipg = inodes_per_cg; sblock.e2fs.e2fs_mtime = 0; sblock.e2fs.e2fs_wtime = tv.tv_sec; sblock.e2fs.e2fs_mnt_count = 0; /* XXX: should add some entropy to avoid checking all fs at once? */ sblock.e2fs.e2fs_max_mnt_count = EXT2_DEF_MAX_MNT_COUNT; sblock.e2fs.e2fs_magic = E2FS_MAGIC; sblock.e2fs.e2fs_state = E2FS_ISCLEAN; sblock.e2fs.e2fs_beh = E2FS_BEH_DEFAULT; sblock.e2fs.e2fs_minrev = 0; sblock.e2fs.e2fs_lastfsck = tv.tv_sec; sblock.e2fs.e2fs_fsckintv = EXT2_DEF_FSCKINTV; /* * Maybe we can use E2FS_OS_FREEBSD here and it would be more proper, * but the purpose of this newfs_ext2fs(8) command is to provide * a filesystem which can be recognized by firmware on some * Linux based appliances that can load bootstrap files only from * (their native) ext2fs, and anyway we will (and should) try to * act like them as much as possible. * * Anyway, I hope that all newer such boxes will keep their support * for the "GOOD_OLD_REV" ext2fs. */ sblock.e2fs.e2fs_creator = E2FS_OS_LINUX; if (Oflag == 0) { sblock.e2fs.e2fs_rev = E2FS_REV0; sblock.e2fs.e2fs_features_compat = 0; sblock.e2fs.e2fs_features_incompat = 0; sblock.e2fs.e2fs_features_rocompat = 0; } else { sblock.e2fs.e2fs_rev = E2FS_REV1; /* * e2fsprogs say "REV1" is "dynamic" so * it isn't quite a version and maybe it means * "extended from REV0 so check compat features." * * XXX: We don't have any native tool to activate * the EXT2F_COMPAT_RESIZE feature and * fsck_ext2fs(8) might not fix structures for it. */ sblock.e2fs.e2fs_features_compat = EXT2F_COMPAT_RESIZE; sblock.e2fs.e2fs_features_incompat = EXT2F_INCOMPAT_FTYPE; sblock.e2fs.e2fs_features_rocompat = EXT2F_ROCOMPAT_SPARSESUPER | EXT2F_ROCOMPAT_LARGEFILE; } sblock.e2fs.e2fs_ruid = geteuid(); sblock.e2fs.e2fs_rgid = getegid(); sblock.e2fs.e2fs_first_ino = EXT2_FIRSTINO; sblock.e2fs.e2fs_inode_size = inodesize; /* e2fs_block_group_nr is set on writing superblock to each group */ uuid_create(&uuid, &uustat); if (uustat != uuid_s_ok) errx(EXIT_FAILURE, "Failed to generate uuid\n"); uuid_enc_le(sblock.e2fs.e2fs_uuid, &uuid); if (volname != NULL) { if (strlen(volname) > sizeof(sblock.e2fs.e2fs_vname)) errx(EXIT_FAILURE, "Volume name is too long"); strlcpy(sblock.e2fs.e2fs_vname, volname, sizeof(sblock.e2fs.e2fs_vname)); } sblock.e2fs.e2fs_fsmnt[0] = '\0'; sblock.e2fs_fsmnt[0] = '\0'; sblock.e2fs.e2fs_algo = 0; /* XXX unsupported? */ sblock.e2fs.e2fs_prealloc = 0; /* XXX unsupported? */ sblock.e2fs.e2fs_dir_prealloc = 0; /* XXX unsupported? */ /* calculate blocks for reserved group descriptors for resize */ sblock.e2fs.e2fs_reserved_ngdb = 0; if (sblock.e2fs.e2fs_rev > E2FS_REV0 && (sblock.e2fs.e2fs_features_compat & EXT2F_COMPAT_RESIZE) != 0) { uint64_t target_blocks; uint target_ncg, target_ngdb, reserved_ngdb; /* reserve descriptors for size as 1024 times as current */ target_blocks = (sblock.e2fs.e2fs_bcount - sblock.e2fs.e2fs_first_dblock) * 1024ULL; /* number of blocks must be in uint32_t */ if (target_blocks > UINT32_MAX) target_blocks = UINT32_MAX; target_ncg = howmany(target_blocks, sblock.e2fs.e2fs_bpg); target_ngdb = howmany(sizeof(struct ext2_gd) * target_ncg, sblock.e2fs_bsize); /* * Reserved group descriptor blocks are preserved as * the second level double indirect reference blocks in * the EXT2_RESIZEINO inode, so the maximum number of * the blocks is NINDIR(fs). * (see also descriptions in init_resizeino() function) * * We check a number including current e2fs_ngdb here * because they will be moved into reserved gdb on * possible future size shrink, though e2fsprogs don't * seem to care about it. */ if (target_ngdb > NINDIR(&sblock)) target_ngdb = NINDIR(&sblock); reserved_ngdb = target_ngdb - sblock.e2fs_ngdb; /* make sure reserved_ngdb fits in the last cg */ if (reserved_ngdb >= blocks_lastcg - cgoverhead(ncg - 1)) reserved_ngdb = blocks_lastcg - cgoverhead(ncg - 1); if (reserved_ngdb == 0) { /* if no space for reserved gdb, disable the feature */ sblock.e2fs.e2fs_features_compat &= ~EXT2F_COMPAT_RESIZE; } sblock.e2fs.e2fs_reserved_ngdb = reserved_ngdb; } /* * Initialize group descriptors */ gd = malloc(sblock.e2fs_ngdb * bsize); if (gd == NULL) errx(EXIT_FAILURE, "Can't allocate descriptors buffer"); memset(gd, 0, sblock.e2fs_ngdb * bsize); fbcount = 0; ficount = 0; for (cylno = 0; cylno < ncg; cylno++) { uint boffset; boffset = cgbase(&sblock, cylno); if (sblock.e2fs.e2fs_rev == E2FS_REV0 || (sblock.e2fs.e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) == 0 || cg_has_sb(cylno)) { boffset += NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb; if (sblock.e2fs.e2fs_rev > E2FS_REV0 && (sblock.e2fs.e2fs_features_compat & EXT2F_COMPAT_RESIZE) != 0) boffset += sblock.e2fs.e2fs_reserved_ngdb; } gd[cylno].ext2bgd_b_bitmap = boffset; boffset += NBLOCK_BLOCK_BITMAP; gd[cylno].ext2bgd_i_bitmap = boffset; boffset += NBLOCK_INODE_BITMAP; gd[cylno].ext2bgd_i_tables = boffset; if (cylno == (ncg - 1)) gd[cylno].ext2bgd_nbfree = blocks_lastcg - cgoverhead(cylno); else gd[cylno].ext2bgd_nbfree = sblock.e2fs.e2fs_bpg - cgoverhead(cylno); fbcount += gd[cylno].ext2bgd_nbfree; gd[cylno].ext2bgd_nifree = sblock.e2fs.e2fs_ipg; if (cylno == 0) { /* take reserved inodes off nifree */ gd[cylno].ext2bgd_nifree -= EXT2_RESERVED_INODES; } ficount += gd[cylno].ext2bgd_nifree; gd[cylno].ext2bgd_ndirs = 0; } sblock.e2fs.e2fs_fbcount = fbcount; sblock.e2fs.e2fs_ficount = ficount; /* * Dump out summary information about file system. */ if (verbosity > 0) { printf("%s: %u.%1uMB (%" PRId64 " sectors) " "block size %u, fragment size %u\n", fsys, (uint)(((uint64_t)bcount * bsize) / (1024 * 1024)), (uint)((uint64_t)bcount * bsize - rounddown((uint64_t)bcount * bsize, 1024 * 1024)) / 1024 / 100, fssize, bsize, fsize); printf("\tusing %u block groups of %u.0MB, %u blks, " "%u inodes.\n", ncg, bsize * sblock.e2fs.e2fs_bpg / (1024 * 1024), sblock.e2fs.e2fs_bpg, sblock.e2fs.e2fs_ipg); } /* * allocate space for superblock and group descriptors */ iobufsize = (NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb) * sblock.e2fs_bsize; iobuf = mmap(0, iobufsize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, 0); if (iobuf == NULL) errx(EXIT_FAILURE, "Cannot allocate I/O buffer\n"); memset(iobuf, 0, iobufsize); /* * We now start writing to the filesystem */ if (!Nflag) { static const uint pbsize[] = { 1024, 2048, 4096, 0 }; uint pblock, epblock; /* * Validate the given file system size. * Verify that its last block can actually be accessed. * Convert to file system fragment sized units. */ if (fssize <= 0) errx(EXIT_FAILURE, "Preposterous size %" PRId64 "\n", fssize); wtfs(fssize - 1, sectorsize, iobuf); /* * Ensure there is nothing that looks like a filesystem * superblock anywhere other than where ours will be. * If fsck_ext2fs finds the wrong one all hell breaks loose! * * XXX: needs to check how fsck_ext2fs programs even * on other OSes determine alternate superblocks */ for (i = 0; pbsize[i] != 0; i++) { epblock = (uint64_t)bcount * bsize / pbsize[i]; for (pblock = ((pbsize[i] == SBSIZE) ? 1 : 0); pblock < epblock; pblock += pbsize[i] * NBBY /* bpg */) zap_old_sblock((daddr_t)pblock * pbsize[i] / sectorsize); } } if (verbosity >= 3) printf("super-block backups (for fsck_ext2fs -b #) at:\n"); /* If we are printing more than one line of numbers, line up columns */ fld_width = verbosity < 4 ? 1 : snprintf(NULL, 0, "%" PRIu64, (uint64_t)cgbase(&sblock, ncg - 1)); /* Get terminal width */ if (ioctl(fileno(stdout), TIOCGWINSZ, &winsize) == 0) max_cols = winsize.ws_col; else max_cols = 80; if (Nflag && verbosity == 3) /* Leave space to add " ..." after one row of numbers */ max_cols -= 4; #define BASE 0x10000 /* For some fixed-point maths */ col = 0; delta = verbosity > 2 ? 0 : max_cols * BASE / ncg; for (cylno = 0; cylno < ncg; cylno++) { fflush(stdout); initcg(cylno); if (verbosity < 2) continue; /* the first one is a master, not backup */ if (cylno == 0) continue; /* skip if this cylinder doesn't have a backup */ if (sblock.e2fs.e2fs_rev > E2FS_REV0 && (sblock.e2fs.e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) != 0 && cg_has_sb(cylno) == 0) continue; if (delta > 0) { if (Nflag) /* No point doing dots for -N */ break; /* Print dots scaled to end near RH margin */ for (col += delta; col > BASE; col -= BASE) printf("."); continue; } /* Print superblock numbers */ len = printf(" %*" PRIu64 "," + !col, fld_width, (uint64_t)cgbase(&sblock, cylno)); col += len; if (col + len < max_cols) /* Next number fits */ continue; /* Next number won't fit, need a newline */ if (verbosity <= 3) { /* Print dots for subsequent cylinder groups */ delta = sblock.e2fs_ncg - cylno - 1; if (delta != 0) { if (Nflag) { printf(" ..."); break; } delta = max_cols * BASE / delta; } } col = 0; printf("\n"); } #undef BASE if (col > 0) printf("\n"); if (Nflag) return; /* * Now construct the initial file system, */ if (fsinit(&tv) == 0) errx(EXIT_FAILURE, "Error making filesystem"); /* * Write out the superblock and group descriptors */ sblock.e2fs.e2fs_block_group_nr = 0; sboff = 0; if (cgbase(&sblock, 0) == 0) { /* * If the first block contains the boot block sectors, * (i.e. in case of sblock.e2fs.e2fs_bsize > BBSIZE) * we have to preserve data in it. */ sboff = SBOFF; } e2fs_sbsave(&sblock.e2fs, (struct ext2fs *)(iobuf + sboff)); e2fs_cgsave(gd, (struct ext2_gd *)(iobuf + sblock.e2fs_bsize), sizeof(struct ext2_gd) * sblock.e2fs_ncg); wtfs(fsbtodb(&sblock, cgbase(&sblock, 0)) + sboff / sectorsize, iobufsize - sboff, iobuf + sboff); munmap(iobuf, iobufsize); }