static char *sccsid = "@(#)mkfs.c 1.12 (Berkeley) 01/06/82"; /* * make file system for cylinder-group style file systems * * usage: mkfs special size [ nsect ntrak bsize fsize cpg ] */ #ifndef STANDALONE #include #include #endif #include "../h/param.h" #include "../h/inode.h" #include "../h/fs.h" #include "../h/dir.h" #define UMASK 0755 #define MAXNDIR (MAXBSIZE / sizeof(struct direct)) #define MAXINOPB (MAXBSIZE / sizeof(struct dinode)) #define POWEROF2(num) (((num) & ((num) - 1)) == 0) union { struct fs fs; char pad[MAXBSIZE]; } fsun; #define sblock fsun.fs struct csum *fscs; union { struct cg cg; char pad[MAXBSIZE]; } cgun; #define acg cgun.cg struct dinode zino[MAXIPG]; char *fsys; time_t utime; int fsi; int fso; daddr_t alloc(); main(argc, argv) int argc; char *argv[]; { long c, i, inos, fssize; #ifndef STANDALONE argc--, argv++; time(&utime); if (argc < 2) { printf("usage: mkfs special size [ nsect ntrak bsize fsize cpg ]\n"); exit(1); } fsys = argv[0]; fssize = atoi(argv[1]); fso = creat(fsys, 0666); if(fso < 0) { printf("%s: cannot create\n", fsys); exit(1); } fsi = open(fsys, 0); if(fsi < 0) { printf("%s: cannot open\n", fsys); exit(1); } #else { static char protos[60]; char fsbuf[100]; printf("file sys size: "); gets(protos); fssize = atoi(protos); do { printf("file system: "); gets(fsbuf); fso = open(fsbuf, 1); fsi = open(fsbuf, 0); } while (fso < 0 || fsi < 0); } argc = 0; #endif if (fssize <= 0) printf("preposterous size %d\n", fssize), exit(1); /* * collect and verify the sector and track info */ if (argc > 2) sblock.fs_nsect = atoi(argv[2]); else sblock.fs_nsect = DFLNSECT; if (argc > 3) sblock.fs_ntrak = atoi(argv[3]); else sblock.fs_ntrak = DFLNTRAK; if (sblock.fs_ntrak <= 0) printf("preposterous ntrak %d\n", sblock.fs_ntrak), exit(1); if (sblock.fs_nsect <= 0) printf("preposterous nsect %d\n", sblock.fs_nsect), exit(1); sblock.fs_spc = sblock.fs_ntrak * sblock.fs_nsect; /* * collect and verify the block and fragment sizes */ if (argc > 4) sblock.fs_bsize = atoi(argv[4]); else sblock.fs_bsize = MAXBSIZE; if (argc > 5) sblock.fs_fsize = atoi(argv[5]); else sblock.fs_fsize = MAX(sblock.fs_bsize / DESFRAG, DEV_BSIZE); if (!POWEROF2(sblock.fs_bsize)) { printf("block size must be a power of 2, not %d\n", sblock.fs_bsize); exit(1); } if (!POWEROF2(sblock.fs_fsize)) { printf("fragment size must be a power of 2, not %d\n", sblock.fs_fsize); exit(1); } if (sblock.fs_fsize < DEV_BSIZE) { printf("fragment size %d is too small, minimum is %d\n", sblock.fs_fsize, DEV_BSIZE); exit(1); } if (sblock.fs_bsize < MINBSIZE) { printf("block size %d is too small, minimum is %d\n", sblock.fs_bsize, MINBSIZE); exit(1); } if (sblock.fs_bsize < sblock.fs_fsize) { printf("block size (%d) cannot be smaller than fragment size (%d)\n", sblock.fs_bsize, sblock.fs_fsize); exit(1); } sblock.fs_frag = sblock.fs_bsize / sblock.fs_fsize; if (sblock.fs_frag > MAXFRAG) { printf("fragment size %d is too small, minimum with block size %d is %d\n", sblock.fs_fsize, sblock.fs_bsize, sblock.fs_bsize / MAXFRAG); exit(1); } /* * collect and verify the number of cylinders per group */ if (argc > 6) { sblock.fs_cpg = atoi(argv[6]); sblock.fs_fpg = (sblock.fs_cpg * sblock.fs_spc) / NSPF(&sblock); } else { sblock.fs_cpg = DESCPG; sblock.fs_fpg = (sblock.fs_cpg * sblock.fs_spc) / NSPF(&sblock); while (sblock.fs_fpg / sblock.fs_frag > MAXBPG(&sblock)) { --sblock.fs_cpg; sblock.fs_fpg = (sblock.fs_cpg * sblock.fs_spc) / NSPF(&sblock); } } if (sblock.fs_cpg < 1) { printf("cylinder groups must have at least 1 cylinder\n"); exit(1); } if (sblock.fs_cpg > MAXCPG) { printf("cylinder groups are limited to %d cylinders\n", MAXCPG); exit(1); } /* * Now have size for file system and nsect and ntrak. * Determine number of cylinders and blocks in the file system. */ sblock.fs_size = fssize = dbtofsb(&sblock, fssize); sblock.fs_ncyl = fssize * NSPF(&sblock) / sblock.fs_spc; if (sblock.fs_spc > MAXBPC * NSPB(&sblock)) { printf("too many sectors per cylinder (%d sectors)\n", sblock.fs_spc); while (sblock.fs_spc > MAXBPC * NSPB(&sblock)) sblock.fs_bsize <<= 1; printf("nsect %d, and ntrak %d, requires block size of %d\n", sblock.fs_nsect, sblock.fs_ntrak, sblock.fs_bsize); exit(1); } /* * Validate specified/determined cpg. */ if (sblock.fs_spc > MAXBPG(&sblock) * NSPB(&sblock)) { printf("too many sectors per cylinder (%d sectors)\n", sblock.fs_spc); while(sblock.fs_spc > MAXBPG(&sblock) * NSPB(&sblock)) { sblock.fs_bsize <<= 1; if (sblock.fs_frag < MAXFRAG) sblock.fs_frag <<= 1; else sblock.fs_fsize <<= 1; } printf("nsect %d, and ntrak %d, requires block size of %d,\n", sblock.fs_nsect, sblock.fs_ntrak, sblock.fs_bsize); printf("\tand fragment size of %d\n", sblock.fs_fsize); exit(1); } if (sblock.fs_fpg > MAXBPG(&sblock) * sblock.fs_frag) { printf("cylinder group too large (%d cylinders); ", sblock.fs_cpg); printf("max: %d cylinders\n", MAXBPG(&sblock) * sblock.fs_frag / (sblock.fs_fpg / sblock.fs_cpg)); exit(1); } sblock.fs_cgsize = roundup(sizeof(struct cg) + howmany(sblock.fs_fpg, NBBY), sblock.fs_fsize); /* * Compute/validate number of cylinder groups. */ if (fssize * NSPF(&sblock) > sblock.fs_ncyl * sblock.fs_spc) { printf("%d sector(s) in last cylinder unused\n", fssize * NSPF(&sblock) - sblock.fs_ncyl * sblock.fs_spc); } sblock.fs_ncg = sblock.fs_ncyl / sblock.fs_cpg; if (sblock.fs_ncyl % sblock.fs_cpg) sblock.fs_ncg++; if ((sblock.fs_spc * sblock.fs_cpg) % NSPF(&sblock)) { printf("mkfs: nsect %d, ntrak %d, cpg %d is not tolerable\n", sblock.fs_nsect, sblock.fs_ntrak, sblock.fs_cpg); printf("as this would would have cyl groups whose size\n"); printf("is not a multiple of %d; choke!\n", sblock.fs_fsize); exit(1); } fscs = (struct csum *) calloc(1, roundup(sblock.fs_ncg * sizeof (struct csum), sblock.fs_bsize)); /* * Compute number of inode blocks per cylinder group. * Start with one inode per NBPI bytes; adjust as necessary. */ inos = ((fssize * sblock.fs_fsize) / MAX(NBPI, sblock.fs_fsize)) / INOPB(&sblock); if (inos <= 0) inos = 1; sblock.fs_ipg = ((inos / sblock.fs_ncg) + 1) * INOPB(&sblock); if (sblock.fs_ipg > MAXIPG) sblock.fs_ipg = MAXIPG; if (cgdmin(0,&sblock) >= sblock.fs_fpg) { printf("inode blocks/cyl group (%d) >= data blocks (%d)\n", cgdmin(0,&sblock) / sblock.fs_frag, sblock.fs_fpg / sblock.fs_frag); printf("number of cylinder per cylinder group must be increased\n"); exit(1); } /* * calculate the available blocks for each rotational position */ for (i = 0; i < NRPOS; i++) sblock.fs_postbl[i] = -1; for (i = 0; i < sblock.fs_spc; i += NSPB(&sblock)) /* void */; for (i -= NSPB(&sblock); i >= 0; i -= NSPB(&sblock)) { c = i % sblock.fs_nsect * NRPOS / sblock.fs_nsect; sblock.fs_rotbl[i / NSPB(&sblock)] = sblock.fs_postbl[c]; sblock.fs_postbl[c] = i / NSPB(&sblock); } /* * fill in remaining fields of the super block */ sblock.fs_csaddr = cgdmin(0, &sblock); sblock.fs_cssize = sblock.fs_ncg * sizeof(struct csum); sblock.fs_rotdelay = ROTDELAY; sblock.fs_minfree = MINFREE; sblock.fs_magic = FS_MAGIC; sblock.fs_sblkno = SBLOCK; sblock.fs_cgrotor = 0; sblock.fs_cstotal.cs_ndir = 0; sblock.fs_cstotal.cs_nbfree = 0; sblock.fs_cstotal.cs_nifree = 0; sblock.fs_cstotal.cs_nffree = 0; sblock.fs_fmod = 0; sblock.fs_ronly = 0; /* * Dump out summary information about file system. */ printf("%s:\t%d sectors in %d cylinders of %d tracks, %d sectors\n", fsys, sblock.fs_size * NSPF(&sblock), sblock.fs_ncyl, sblock.fs_ntrak, sblock.fs_nsect); printf("\t%.1fMb in %d cyl groups (%d c/g, %.2fMb/g, %d i/g)\n", (float)sblock.fs_size * sblock.fs_fsize * 1e-6, sblock.fs_ncg, sblock.fs_cpg, (float)sblock.fs_fpg * sblock.fs_fsize * 1e-6, sblock.fs_ipg); /* * Now build the cylinders group blocks and * then print out indices of cylinder groups. */ for (c = 0; c < sblock.fs_ncg; c++) initcg(c); if (sblock.fs_ncg == 1) printf("Warning, no super-block backups with only one cylinder group\n"); else printf("\tsuper-block backups (for fsck -b#) at %d+k*%d (%d .. %d)\n", SBLOCK, fsbtodb(&sblock, cgsblock(1, &sblock)) - SBLOCK, fsbtodb(&sblock, cgsblock(1, &sblock)), fsbtodb(&sblock, cgsblock(sblock.fs_ncg - 1, &sblock))); /* * Now construct the initial file system, * then write out the super-block. */ fsinit(); sblock.fs_time = utime; wtfs(SBLOCK, SBSIZE, (char *)&sblock); for (i = 0; i < sblock.fs_cssize; i += sblock.fs_bsize) wtfs(fsbtodb(&sblock, sblock.fs_csaddr + i / sblock.fs_fsize), sblock.fs_bsize, ((char *)fscs) + i); /* * Write out the duplicate super blocks */ for (c = 1; c < sblock.fs_ncg; c++) wtfs(fsbtodb(&sblock, cgsblock(c, &sblock)), SBSIZE, (char *)&sblock); #ifndef STANDALONE exit(0); #endif } /* * Initialize a cylinder group. */ initcg(c) int c; { daddr_t cbase, d, dmin, dmax; long i, j, s; register struct csum *cs; /* * Determine block bounds for cylinder group. * Allow space for super block summary information in first * cylinder group. */ cbase = cgbase(c,&sblock); dmax = cbase + sblock.fs_fpg; if (dmax > sblock.fs_size) dmax = sblock.fs_size; dmin = cgdmin(c,&sblock) - cbase; d = cbase; cs = fscs+c; acg.cg_time = utime; acg.cg_magic = CG_MAGIC; acg.cg_cgx = c; acg.cg_ncyl = sblock.fs_cpg; acg.cg_niblk = sblock.fs_ipg; acg.cg_ndblk = dmax - cbase; acg.cg_cs.cs_ndir = 0; acg.cg_cs.cs_nffree = 0; acg.cg_cs.cs_nbfree = 0; acg.cg_cs.cs_nifree = 0; acg.cg_rotor = dmin; acg.cg_frotor = dmin; acg.cg_irotor = 0; for (i = 0; i < sblock.fs_frag; i++) { acg.cg_frsum[i] = 0; } for (i = 0; i < sblock.fs_ipg; ) { for (j = INOPB(&sblock); j > 0; j--) { clrbit(acg.cg_iused, i); i++; } acg.cg_cs.cs_nifree += INOPB(&sblock); } if (c == 0) for (i = 0; i < ROOTINO; i++) { setbit(acg.cg_iused, i); acg.cg_cs.cs_nifree--; } while (i < MAXIPG) { clrbit(acg.cg_iused, i); i++; } lseek(fso, fsbtodb(&sblock, cgimin(c,&sblock)) * DEV_BSIZE, 0); if (write(fso, (char *)zino, sblock.fs_ipg * sizeof (struct dinode)) != sblock.fs_ipg * sizeof (struct dinode)) printf("write error %D\n", tell(fso) / sblock.fs_bsize); for (i = 0; i < MAXCPG; i++) for (j = 0; j < NRPOS; j++) acg.cg_b[i][j] = 0; if (c == 0) { dmin += howmany(sblock.fs_cssize, sblock.fs_bsize) * sblock.fs_frag; } for (d = 0; d < dmin; d += sblock.fs_frag) clrblock(&sblock, acg.cg_free, d/sblock.fs_frag); while ((d+sblock.fs_frag) <= dmax - cbase) { setblock(&sblock, acg.cg_free, d/sblock.fs_frag); acg.cg_cs.cs_nbfree++; s = d * NSPF(&sblock); acg.cg_b[s / sblock.fs_spc] [s % sblock.fs_nsect * NRPOS / sblock.fs_nsect]++; d += sblock.fs_frag; } if (d < dmax - cbase) for (; d < dmax - cbase; d++) { setbit(acg.cg_free, d); acg.cg_cs.cs_nffree++; } for (; d < MAXBPG(&sblock); d++) clrbit(acg.cg_free, d); sblock.fs_dsize += acg.cg_ndblk - dmin; sblock.fs_cstotal.cs_ndir += acg.cg_cs.cs_ndir; sblock.fs_cstotal.cs_nffree += acg.cg_cs.cs_nffree; sblock.fs_cstotal.cs_nbfree += acg.cg_cs.cs_nbfree; sblock.fs_cstotal.cs_nifree += acg.cg_cs.cs_nifree; *cs = acg.cg_cs; wtfs(fsbtodb(&sblock, cgtod(c, &sblock)), sblock.fs_bsize, (char *)&acg); } /* * initialize the file system */ struct inode node; #define PREDEFDIR 3 struct direct root_dir[MAXNDIR] = { { ROOTINO, ".", 0, IFDIR }, { ROOTINO, "..", 0, IFDIR }, { LOSTFOUNDINO, "lost+found", 0, IFDIR }, }; struct direct lost_found_dir[MAXNDIR] = { { LOSTFOUNDINO, ".", 0, IFDIR }, { ROOTINO, "..", 0, IFDIR }, }; fsinit() { /* * initialize the node */ node.i_atime = utime; node.i_mtime = utime; node.i_ctime = utime; /* * create the lost+found directory */ node.i_number = LOSTFOUNDINO; node.i_mode = IFDIR | UMASK; node.i_nlink = 2; node.i_size = sblock.fs_bsize; node.i_db[0] = alloc(node.i_size, node.i_mode); wtfs(fsbtodb(&sblock, node.i_db[0]), node.i_size, lost_found_dir); iput(&node); /* * create the root directory */ node.i_number = ROOTINO; node.i_mode = IFDIR | UMASK; node.i_nlink = PREDEFDIR; node.i_size = PREDEFDIR * sizeof(struct direct); node.i_db[0] = alloc(sblock.fs_fsize, node.i_mode); wtfs(fsbtodb(&sblock, node.i_db[0]), sblock.fs_fsize, root_dir); iput(&node); } /* * allocate a block or frag */ daddr_t alloc(size, mode) int size; int mode; { int c, i, s, frag; daddr_t d; c = 0; rdfs(fsbtodb(&sblock, cgtod(0,&sblock)), roundup(sblock.fs_cgsize, DEV_BSIZE), (char *)&acg); if (acg.cg_cs.cs_nbfree == 0) { printf("first cylinder group ran out of space\n"); return (0); } for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag) if (isblock(&sblock, acg.cg_free, d / sblock.fs_frag)) goto goth; printf("internal error: can't find block in cyl 0\n"); return (0); goth: clrblock(&sblock, acg.cg_free, d / sblock.fs_frag); acg.cg_cs.cs_nbfree--; sblock.fs_cstotal.cs_nbfree--; fscs[0].cs_nbfree--; if (mode & IFDIR) { acg.cg_cs.cs_ndir++; sblock.fs_cstotal.cs_ndir++; fscs[0].cs_ndir++; } s = d * NSPF(&sblock); acg.cg_b[s / sblock.fs_spc] [s % sblock.fs_nsect * NRPOS / sblock.fs_nsect]--; if (size != sblock.fs_bsize) { frag = howmany(size, sblock.fs_fsize); fscs[0].cs_nffree += sblock.fs_frag - frag; sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag; acg.cg_cs.cs_nffree += sblock.fs_frag - frag; acg.cg_frsum[sblock.fs_frag - frag]++; for (i = frag; i < sblock.fs_frag; i++) setbit(acg.cg_free, d+i); } wtfs(fsbtodb(&sblock, cgtod(0,&sblock)), roundup(sblock.fs_cgsize, DEV_BSIZE), (char *)&acg); return (d); } /* * Allocate an inode on the disk */ iput(ip) register struct inode *ip; { struct dinode buf[MAXINOPB]; daddr_t d; int c; c = itog(ip->i_number, &sblock); rdfs(fsbtodb(&sblock, cgtod(c,&sblock)), roundup(sblock.fs_cgsize, DEV_BSIZE), (char *)&acg); acg.cg_cs.cs_nifree--; setbit(acg.cg_iused, ip->i_number); wtfs(fsbtodb(&sblock, cgtod(c,&sblock)), roundup(sblock.fs_cgsize, DEV_BSIZE), (char *)&acg); sblock.fs_cstotal.cs_nifree--; fscs[0].cs_nifree--; if(ip->i_number >= sblock.fs_ipg * sblock.fs_ncg) { printf("fsinit: inode value out of range (%d).\n", ip->i_number); exit(1); } d = fsbtodb(&sblock, itod(ip->i_number, &sblock)); rdfs(d, sblock.fs_bsize, buf); buf[itoo(ip->i_number, &sblock)].di_ic = ip->i_ic; wtfs(d, sblock.fs_bsize, buf); } /* * read a block from the file system */ rdfs(bno, size, bf) daddr_t bno; int size; char *bf; { int n; if (lseek(fsi, bno * DEV_BSIZE, 0) < 0) { printf("seek error: %ld\n", bno); perror("rdfs"); exit(1); } n = read(fsi, bf, size); if(n != size) { printf("read error: %ld\n", bno); perror("rdfs"); exit(1); } } /* * write a block to the file system */ wtfs(bno, size, bf) daddr_t bno; int size; char *bf; { int n; lseek(fso, bno * DEV_BSIZE, 0); if (lseek(fso, bno * DEV_BSIZE, 0) < 0) { printf("seek error: %ld\n", bno); perror("wtfs"); exit(1); } n = write(fso, bf, size); if(n != size) { printf("write error: %D\n", bno); perror("wtfs"); exit(1); } } /* * check if a block is available */ isblock(fs, cp, h) struct fs *fs; unsigned char *cp; int h; { unsigned char mask; switch (fs->fs_frag) { case 8: return (cp[h] == 0xff); case 4: mask = 0x0f << ((h & 0x1) << 2); return ((cp[h >> 1] & mask) == mask); case 2: mask = 0x03 << ((h & 0x3) << 1); return ((cp[h >> 2] & mask) == mask); case 1: mask = 0x01 << (h & 0x7); return ((cp[h >> 3] & mask) == mask); default: fprintf(stderr, "isblock bad fs_frag %d\n", fs->fs_frag); return; } } /* * take a block out of the map */ clrblock(fs, cp, h) struct fs *fs; unsigned char *cp; int h; { switch ((fs)->fs_frag) { case 8: cp[h] = 0; return; case 4: cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); return; case 2: cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); return; case 1: cp[h >> 3] &= ~(0x01 << (h & 0x7)); return; default: fprintf(stderr, "clrblock bad fs_frag %d\n", fs->fs_frag); return; } } /* * put a block into the map */ setblock(fs, cp, h) struct fs *fs; unsigned char *cp; int h; { switch (fs->fs_frag) { case 8: cp[h] = 0xff; return; case 4: cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); return; case 2: cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); return; case 1: cp[h >> 3] |= (0x01 << (h & 0x7)); return; default: fprintf(stderr, "setblock bad fs_frag %d\n", fs->fs_frag); return; } }