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- /*
- * fsck.c - a file system consistency checker for Linux.
- *
- * (C) 1991, 1992 Linus Torvalds. This file may be redistributed
- * as per the GNU copyleft.
- */
-
- /*
- * 09.11.91 - made the first rudimetary functions
- *
- * 10.11.91 - updated, does checking, no repairs yet.
- * Sent out to the mailing-list for testing.
- *
- * 14.11.91 - Testing seems to have gone well. Added some
- * correction-code, and changed some functions.
- *
- * 15.11.91 - More correction code. Hopefully it notices most
- * cases now, and tries to do something about them.
- *
- * 16.11.91 - More corrections (thanks to Mika Jalava). Most
- * things seem to work now. Yeah, sure.
- *
- *
- * 19.04.92 - Had to start over again from this old version, as a
- * kernel bug ate my enhanced fsck in february.
- *
- * I've had no time to add comments - hopefully the function names
- * are comments enough. As with all file system checkers, this assumes
- * the file system is quiescent - don't use it on a mounted device
- * unless you can be sure nobody is writing to it (and remember that the
- * kernel can write to it when it searches for files).
- *
- * Usuage: fsck [-larvsm] device
- * -l for a listing of all the filenames
- * -a for automatic repairs (not implemented)
- * -r for repairs (interactive) (not implemented)
- * -v for verbose (tells how many files)
- * -s for super-block info
- * -m for minix-like "mode not cleared" warnings
- *
- * The device may be a block device or a image of one, but this isn't
- * enforced (but it's not much fun on a character device :-).
- */
-
- #include <stdio.h>
- #include <unistd.h>
- #include <string.h>
- #include <fcntl.h>
- #include <ctype.h>
- #include <stdlib.h>
- #include <termios.h>
- #include <sys/stat.h>
-
- #include <linux/fs.h>
- #include <linux/minix_fs.h>
-
- #ifndef __GNUC__
- #error "needs gcc for the bitop-__asm__'s"
- #endif
-
- #ifndef __linux__
- #define volatile
- #endif
-
- #define ROOT_INO 1
-
- #define UPPER(size,n) ((size+((n)-1))/(n))
- #define INODE_SIZE (sizeof(struct minix_inode))
- #define INODE_BLOCKS UPPER(INODES,MINIX_INODES_PER_BLOCK)
- #define INODE_BUFFER_SIZE (INODE_BLOCKS * BLOCK_SIZE)
-
- #define BITS_PER_BLOCK (BLOCK_SIZE<<3)
-
- static char * program_name = "fsck";
- static char * device_name = NULL;
- static int IN;
- static int repair=0, automatic=0, verbose=0, list=0, show=0, warn_mode=0;
- static int directory=0, regular=0, blockdev=0, chardev=0, links=0,
- symlinks=0, total=0;
-
- static int changed = 0; /* flags if the filesystem has been changed */
-
- /* File-name data */
- #define MAX_DEPTH 50
- static int name_depth = 0;
- static char name_list[MAX_DEPTH][MINIX_NAME_LEN+1];
-
- static char * inode_buffer = NULL;
- #define Inode (((struct minix_inode *) inode_buffer)-1)
- static char super_block_buffer[BLOCK_SIZE];
- #define Super (*(struct minix_super_block *)super_block_buffer)
- #define INODES ((unsigned long)Super.s_ninodes)
- #define ZONES ((unsigned long)Super.s_nzones)
- #define IMAPS ((unsigned long)Super.s_imap_blocks)
- #define ZMAPS ((unsigned long)Super.s_zmap_blocks)
- #define FIRSTZONE ((unsigned long)Super.s_firstdatazone)
- #define ZONESIZE ((unsigned long)Super.s_log_zone_size)
- #define MAXSIZE ((unsigned long)Super.s_max_size)
- #define MAGIC (Super.s_magic)
- #define NORM_FIRSTZONE (2+IMAPS+ZMAPS+INODE_BLOCKS)
-
- static char inode_map[BLOCK_SIZE * MINIX_I_MAP_SLOTS];
- static char zone_map[BLOCK_SIZE * MINIX_Z_MAP_SLOTS];
-
- static unsigned char * inode_count = NULL;
- static unsigned char * zone_count = NULL;
-
- void recursive_check(unsigned int ino);
-
- #define bitop(name,op) \
- static inline int name(char * addr,unsigned int nr) \
- { \
- int __res; \
- __asm__ __volatile__("bt" op "l %1,%2; adcl $0,%0" \
- :"=g" (__res) \
- :"r" (nr),"m" (*(addr)),"0" (0)); \
- return __res; \
- }
-
- bitop(bit,"")
- bitop(setbit,"s")
- bitop(clrbit,"r")
-
- #define inode_in_use(x) (bit(inode_map,(x)))
- #define zone_in_use(x) (bit(zone_map,(x)-FIRSTZONE+1))
-
- #define mark_inode(x) (setbit(inode_map,(x)),changed=1)
- #define unmark_inode(x) (clrbit(inode_map,(x)),changed=1)
-
- #define mark_zone(x) (setbit(zone_map,(x)-FIRSTZONE+1),changed=1)
- #define unmark_zone(x) (clrbit(zone_map,(x)-FIRSTZONE+1),changed=1)
-
- /*
- * Volatile to let gcc know that this doesn't return. When trying
- * to compile this under minix, volatile gives a warning, as
- * exit() isn't defined as volatile under minix.
- */
- volatile void fatal_error(const char * fmt_string)
- {
- fprintf(stderr,fmt_string,program_name,device_name);
- exit(1);
- }
-
- #define usage() fatal_error("Usage: %s [-larvsm] /dev/name\n")
- #define die(str) fatal_error("%s: " str "\n")
-
- /*
- * This simply goes through the file-name data and prints out the
- * current file.
- */
- void print_current_name(void)
- {
- int i=0;
-
- while (i<name_depth)
- printf("/%.14s",name_list[i++]);
- }
-
- int ask(const char * string,int def)
- {
- int c;
-
- if (!repair) {
- printf("\n");
- return 0;
- }
- if (automatic) {
- printf("\n");
- return def;
- }
- printf(def?"%s (y/n)? ":"%s (n/y)? ",string);
- for (;;) {
- fflush(stdout);
- if ((c=getchar())==EOF)
- return def;
- c=toupper(c);
- if (c == 'Y') {
- def = 1;
- break;
- } else if (c == 'N') {
- def = 0;
- break;
- } else if (c == ' ' || c == '\n')
- break;
- }
- if (def)
- printf("y\n");
- else
- printf("n\n");
- return def;
- }
-
- /*
- * check_zone_nr checks to see that *nr is a valid zone nr. If it
- * isn't, it will possibly be repaired. Check_zone_nr sets *corrected
- * if an error was corrected, and returns the zone (0 for no zone
- * or a bad zone-number).
- */
- int check_zone_nr(unsigned short * nr, int * corrected)
- {
- if (!*nr)
- return 0;
- if (*nr < FIRSTZONE)
- printf("Zone nr < FIRSTZONE in file `");
- else if (*nr >= ZONES)
- printf("Zone nr >= ZONES in file `");
- else
- return *nr;
- print_current_name();
- printf("'.");
- if (ask("Remove block",1)) {
- *nr = 0;
- *corrected = 1;
- }
- return 0;
- }
-
- /*
- * read-block reads block nr into the buffer at addr.
- */
- void read_block(unsigned int nr, char * addr)
- {
- if (!nr) {
- memset(addr,0,BLOCK_SIZE);
- return;
- }
- if (BLOCK_SIZE*nr != lseek(IN, BLOCK_SIZE*nr, SEEK_SET)) {
- printf("Read error: unable to seek to block in file '");
- print_current_name();
- printf("'\n");
- memset(addr,0,BLOCK_SIZE);
- } else if (BLOCK_SIZE != read(IN, addr, BLOCK_SIZE)) {
- printf("Read error: bad block in file '");
- print_current_name();
- printf("'\n");
- memset(addr,0,BLOCK_SIZE);
- }
- }
-
- /*
- * write_block writes block nr to disk.
- */
- void write_block(unsigned int nr, char * addr)
- {
- if (!nr)
- return;
- if (nr < FIRSTZONE || nr >= ZONES) {
- printf("Internal error: trying to write bad block\n"
- "Write request ignored\n");
- return;
- }
- if (BLOCK_SIZE*nr != lseek(IN, BLOCK_SIZE*nr, SEEK_SET))
- die("seek failed in write_block");
- if (BLOCK_SIZE != write(IN, addr, BLOCK_SIZE)) {
- printf("Write error: bad block in file '");
- print_current_name();
- printf("'\n");
- }
- }
-
- /*
- * map-block calculates the absolute block nr of a block in a file.
- * It sets 'changed' if the inode has needed changing, and re-writes
- * any indirect blocks with errors.
- */
- int map_block(struct minix_inode * inode, unsigned int blknr)
- {
- unsigned short ind[BLOCK_SIZE>>1];
- unsigned short dind[BLOCK_SIZE>>1];
- int blk_chg, block, result;
-
- if (blknr<7)
- return check_zone_nr(inode->i_zone + blknr, &changed);
- blknr -= 7;
- if (blknr<512) {
- block = check_zone_nr(inode->i_zone + 7, &changed);
- read_block(block, (char *) ind);
- blk_chg = 0;
- result = check_zone_nr(blknr + ind, &blk_chg);
- if (blk_chg)
- write_block(block, (char *) ind);
- return result;
- }
- blknr -= 512;
- block = check_zone_nr(inode->i_zone + 8, &changed);
- read_block(block, (char *) dind);
- blk_chg = 0;
- result = check_zone_nr(dind + (blknr/512), &blk_chg);
- if (blk_chg)
- write_block(block, (char *) dind);
- block = result;
- read_block(block, (char *) ind);
- blk_chg = 0;
- result = check_zone_nr(ind + (blknr%512), &blk_chg);
- if (blk_chg)
- write_block(block, (char *) ind);
- return result;
- }
-
- void write_tables(void)
- {
- if (BLOCK_SIZE != lseek(IN, BLOCK_SIZE, SEEK_SET))
- die("seek failed in write_tables");
- if (BLOCK_SIZE != write(IN, super_block_buffer, BLOCK_SIZE))
- die("unable to write super-block");
- if (IMAPS*BLOCK_SIZE != write(IN,inode_map,IMAPS*BLOCK_SIZE))
- die("Unable to write inode map");
- if (ZMAPS*BLOCK_SIZE != write(IN,zone_map,ZMAPS*BLOCK_SIZE))
- die("Unable to write zone map");
- if (INODE_BUFFER_SIZE != write(IN,inode_buffer,INODE_BUFFER_SIZE))
- die("Unable to write inodes");
- }
-
- void read_tables(void)
- {
- memset(inode_map,0,sizeof(inode_map));
- memset(zone_map,0,sizeof(zone_map));
- if (BLOCK_SIZE != lseek(IN, BLOCK_SIZE, SEEK_SET))
- die("seek failed");
- if (BLOCK_SIZE != read(IN, super_block_buffer, BLOCK_SIZE))
- die("unable to read super block");
- if (MAGIC != MINIX_SUPER_MAGIC)
- die("bad magic number in super-block");
- if (ZONESIZE != 0 || BLOCK_SIZE != 1024)
- die("Only 1k blocks/zones supported");
- if (!IMAPS || IMAPS > MINIX_I_MAP_SLOTS)
- die("bad s_imap_blocks field in super-block");
- if (!ZMAPS || ZMAPS > MINIX_Z_MAP_SLOTS)
- die("bad s_zmap_blocks field in super-block");
- inode_buffer = malloc(INODE_BUFFER_SIZE);
- if (!inode_buffer)
- die("Unable to allocate buffer for inodes");
- inode_count = malloc(INODES);
- if (!inode_count)
- die("Unable to allocate buffer for inode count");
- zone_count = malloc(ZONES);
- if (!zone_count)
- die("Unable to allocate buffer for zone count");
- if (IMAPS*BLOCK_SIZE != read(IN,inode_map,IMAPS*BLOCK_SIZE))
- die("Unable to read inode map");
- if (ZMAPS*BLOCK_SIZE != read(IN,zone_map,ZMAPS*BLOCK_SIZE))
- die("Unable to read zone map");
- if (INODE_BUFFER_SIZE != read(IN,inode_buffer,INODE_BUFFER_SIZE))
- die("Unable to read inodes");
- if (NORM_FIRSTZONE != FIRSTZONE)
- printf("Warning: Firstzone != Norm_firstzone\n");
- if (show) {
- printf("%d inodes\n",INODES);
- printf("%d blocks\n",ZONES);
- printf("Firstdatazone=%d (%d)\n",FIRSTZONE,NORM_FIRSTZONE);
- printf("Zonesize=%d\n",BLOCK_SIZE<<ZONESIZE);
- printf("Maxsize=%d\n\n",MAXSIZE);
- }
- }
-
- struct minix_inode * get_inode(unsigned int nr)
- {
- struct minix_inode * inode;
-
- if (!nr || nr >= INODES)
- return NULL;
- total++;
- inode = Inode + nr;
- if (!inode_count[nr]) {
- if (!inode_in_use(nr)) {
- printf("Inode %d marked not used, but used for file '",
- nr);
- print_current_name();
- printf("'\n");
- if (repair)
- if (ask("Mark in use",1))
- mark_inode(nr);
- }
- if (S_ISDIR(inode->i_mode))
- directory++;
- else if (S_ISREG(inode->i_mode))
- regular++;
- else if (S_ISCHR(inode->i_mode))
- chardev++;
- else if (S_ISBLK(inode->i_mode))
- blockdev++;
- else if (S_ISLNK(inode->i_mode))
- symlinks++;
- } else
- links++;
- if (!++inode_count[nr]) {
- printf("Warning: inode count too big.\n");
- inode_count[nr]--;
- }
- return inode;
- }
-
- void check_root(void)
- {
- struct minix_inode * inode = Inode + ROOT_INO;
-
- if (!inode || !S_ISDIR(inode->i_mode))
- die("root inode isn't a directory");
- }
-
- static int add_zone(unsigned short * znr, int * corrected)
- {
- int result;
- int block;
-
- result = 0;
- block = check_zone_nr(znr, corrected);
- if (!block)
- return 0;
- if (zone_count[block]) {
- printf("Block has been used before. Now in file `");
- print_current_name();
- printf("'.");
- if (ask("Clear",1)) {
- *znr = 0;
- block = 0;
- *corrected = 1;
- }
- }
- if (!block)
- return 0;
- if (!zone_in_use(block)) {
- printf("Block %d in file `",block);
- print_current_name();
- printf("' is marked not in use.");
- if (ask("Correct",1))
- mark_zone(block);
- }
- if (!++zone_count[block])
- zone_count[block]--;
- return block;
- }
-
- static void add_zone_ind(unsigned short * znr, int * corrected)
- {
- static char blk[BLOCK_SIZE];
- int i, chg_blk=0;
- int block;
-
- block = add_zone(znr, corrected);
- if (!block)
- return;
- read_block(block, blk);
- for (i=0 ; i < (BLOCK_SIZE>>1) ; i++)
- add_zone(i + (unsigned short *) blk, &chg_blk);
- if (chg_blk)
- write_block(block, blk);
- }
-
- static void add_zone_dind(unsigned short * znr, int * corrected)
- {
- static char blk[BLOCK_SIZE];
- int i, blk_chg=0;
- int block;
-
- block = add_zone(znr, corrected);
- if (!block)
- return;
- read_block(block, blk);
- for (i=0 ; i < (BLOCK_SIZE>>1) ; i++)
- add_zone_ind(i + (unsigned short *) blk, &blk_chg);
- if (blk_chg)
- write_block(block, blk);
- }
-
- void check_zones(unsigned int i)
- {
- struct minix_inode * inode;
-
- if (!i || i >= INODES)
- return;
- if (inode_count[i] > 1) /* have we counted this file already? */
- return;
- inode = Inode + i;
- if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode) &&
- !S_ISLNK(inode->i_mode))
- return;
- for (i=0 ; i<7 ; i++)
- add_zone(i + inode->i_zone, &changed);
- add_zone_ind(7 + inode->i_zone, &changed);
- add_zone_dind(8 + inode->i_zone, &changed);
- }
-
- void check_file(struct minix_inode * dir, unsigned int offset)
- {
- static char blk[BLOCK_SIZE];
- struct minix_inode * inode;
- int ino;
- char * name;
- int block;
-
- block = map_block(dir,offset/BLOCK_SIZE);
- read_block(block, blk);
- name = blk + (offset % BLOCK_SIZE) + 2;
- ino = * (unsigned short *) (name-2);
- if (ino >= INODES) {
- print_current_name();
- printf(" contains a bad inode number for file '");
- printf("%.14s'.",name);
- if (ask(" Remove",1)) {
- *(unsigned short *)(name-2) = 0;
- write_block(block, blk);
- }
- ino = 0;
- }
- inode = get_inode(ino);
- if (!offset)
- if (!inode || strcmp(".",name)) {
- print_current_name();
- printf(": bad directory: '.' isn't first\n");
- } else return;
- if (offset == 16)
- if (!inode || strcmp("..",name)) {
- print_current_name();
- printf(": bad directory: '..' isn't second\n");
- } else return;
- if (!inode)
- return;
- if (name_depth < MAX_DEPTH)
- strncpy(name_list[name_depth],name,14);
- name_depth++;
- if (list) {
- if (verbose)
- printf("%6d %07o %3d ",ino,inode->i_mode,inode->i_nlinks);
- print_current_name();
- if (S_ISDIR(inode->i_mode))
- printf(":\n");
- else
- printf("\n");
- }
- check_zones(ino);
- if (inode && S_ISDIR(inode->i_mode))
- recursive_check(ino);
- name_depth--;
- return;
- }
-
- void recursive_check(unsigned int ino)
- {
- struct minix_inode * dir;
- unsigned int offset;
-
- dir = Inode + ino;
- if (!S_ISDIR(dir->i_mode))
- die("internal error");
- if (dir->i_size < 32) {
- print_current_name();
- printf(": bad directory: size<32");
- }
- for (offset = 0 ; offset < dir->i_size ; offset += 16)
- check_file(dir,offset);
- }
-
- int bad_zone(int i)
- {
- char buffer[1024];
-
- if (BLOCK_SIZE*i != lseek(IN, BLOCK_SIZE*i, SEEK_SET))
- die("seek failed in bad_zone");
- return (BLOCK_SIZE != read(IN, buffer, BLOCK_SIZE));
- }
-
- void check_counts(void)
- {
- int i;
-
- for (i=1 ; i < INODES ; i++) {
- if (!inode_in_use(i) && Inode[i].i_mode && warn_mode) {
- printf("Inode %d mode not cleared.",i);
- if (ask("Clear",1)) {
- Inode[i].i_mode = 0;
- changed = 1;
- }
- }
- if (!inode_count[i]) {
- if (!inode_in_use(i))
- continue;
- printf("Inode %d not used, marked used in the bitmap.",i);
- if (ask("Clear",1))
- unmark_inode(i);
- continue;
- }
- if (!inode_in_use(i)) {
- printf("Inode %d used, marked unused in the bitmap.",
- i);
- if (ask("Set",1))
- mark_inode(i);
- }
- if (Inode[i].i_nlinks != inode_count[i]) {
- printf("Inode %d (mode = %07o), i_nlinks=%d, counted=%d.",
- i,Inode[i].i_mode,Inode[i].i_nlinks,inode_count[i]);
- if (ask("Set i_nlinks to count",1)) {
- Inode[i].i_nlinks=inode_count[i];
- changed=1;
- }
- }
- }
- for (i=FIRSTZONE ; i < ZONES ; i++) {
- if (zone_in_use(i) == zone_count[i])
- continue;
- if (!zone_count[i]) {
- if (bad_zone(i))
- continue;
- printf("Zone %d: marked in use, no file uses it.",i);
- if (ask("Unmark",1))
- unmark_zone(i);
- continue;
- }
- printf("Zone %d: %sin use, counted=%d\n",
- i,zone_in_use(i)?"":"not ",zone_count[i]);
- }
- }
-
- void check(void)
- {
- memset(inode_count,0,INODES*sizeof(*inode_count));
- memset(zone_count,0,ZONES*sizeof(*zone_count));
- check_zones(ROOT_INO);
- recursive_check(ROOT_INO);
- check_counts();
- }
-
- int main(int argc, char ** argv)
- {
- struct termios termios,tmp;
- int count;
-
- if (argc && *argv)
- program_name = *argv;
- if (INODE_SIZE * MINIX_INODES_PER_BLOCK != BLOCK_SIZE)
- die("bad inode size");
- while (argc-- > 1) {
- argv++;
- if (argv[0][0] != '-')
- if (device_name)
- usage();
- else
- device_name = argv[0];
- else while (*++argv[0])
- switch (argv[0][0]) {
- case 'l': list=1; break;
- case 'a': automatic=1; repair=1; break;
- case 'r': automatic=0; repair=1; break;
- case 'v': verbose=1; break;
- case 's': show=1; break;
- case 'm': warn_mode=1; break;
- default: usage();
- }
- }
- if (!device_name)
- usage();
- if (repair && !automatic) {
- if (!isatty(0) || !isatty(1))
- die("need terminal for interactive repairs");
- tcgetattr(0,&termios);
- tmp = termios;
- tmp.c_lflag &= ~(ICANON|ECHO);
- tcsetattr(0,TCSANOW,&tmp);
- }
- IN = open(device_name,repair?O_RDWR:O_RDONLY);
- if (IN < 0)
- die("unable to open '%s'");
- for (count=0 ; count<3 ; count++)
- sync();
- read_tables();
- check_root();
- check();
- if (verbose) {
- int i, free;
-
- for (i=1,free=0 ; i < INODES ; i++)
- if (!inode_in_use(i))
- free++;
- printf("\n%6d inodes used (%d%%)\n",(INODES-free-1),
- 100*(INODES-free-1)/(INODES-1));
- for (i=FIRSTZONE,free=0 ; i < ZONES ; i++)
- if (!zone_in_use(i))
- free++;
- printf("%6d zones used (%d%%)\n",(ZONES-free),
- 100*(ZONES-free)/ZONES);
- printf("\n%6d regular files\n"
- "%6d directories\n"
- "%6d character device files\n"
- "%6d block device files\n"
- "%6d links\n"
- "%6d symbolic links\n"
- "------\n"
- "%6d files\n",
- regular,directory,chardev,blockdev,
- links-2*directory+1,symlinks,total-2*directory+1);
- }
- if (changed) {
- write_tables();
- printf( "----------------------------\n"
- "FILE SYSTEM HAS BEEN CHANGED\n"
- "----------------------------\n");
- for (count=0 ; count<3 ; count++)
- sync();
- }
- if (repair && !automatic)
- tcsetattr(0,TCSANOW,&termios);
- return (0);
- }
-