minix/commands/simple/badblocks.c
2009-05-13 15:39:44 +00:00

657 lines
16 KiB
C
Executable file

/* badblocks - collect bad blocks in a file Author: Jacob Bunschoten */
/* Usage "badblocks block_special [Up_to_7_blocks]" */
/* This program is written to handle BADBLOCKS on a hard or floppy disk.
* The program asks for block_numbers. These numbers can be obtained with
* the program readall, written by A. Tanenbaum. It then creates a
* file on the disk containing up to 7 bad blocks.
*
* BUG:
*
* When the zone_size > block_size it can happen that
* the zone is already allocated. This means some
* file is using this zone and may use all the blocks including
* the bad one. This can be cured by inspecting the zone_bitmap
* (is already done) and change the file if this zone is used.
* This means that another zone must be allocated and
* the inode wich claims this zone must be found and changed.
*
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <minix/config.h>
#include <minix/type.h>
#include <fcntl.h>
#include <unistd.h>
#include <dirent.h>
#include <stdlib.h>
#include "../../servers/mfs/const.h" /* must be included before stdio.h */
#undef printf /* so its define of printf can be undone */
#include "../../servers/mfs/type.h"
#include <string.h>
#include <stdio.h>
#define EXTERN extern
#include "../../servers/mfs/super.h"
_PROTOTYPE(int main, (int argc, char **argv));
_PROTOTYPE(void rw_super, (int flag));
_PROTOTYPE(void get_super, (void));
_PROTOTYPE(void put_super, (void));
_PROTOTYPE(void rw_inode, (struct stat * stat_ptr, int rw_mode));
_PROTOTYPE(void get_inode, (struct stat * stat_ptr));
_PROTOTYPE(void put_inode, (struct stat * stat_ptr));
_PROTOTYPE(long rd_cmdline, (int argc, char *argv[]));
_PROTOTYPE(void modify, (int nr_blocks));
_PROTOTYPE(void save_blk, (block_t blk_num));
_PROTOTYPE(void reset_blks, (void));
_PROTOTYPE(void show_blks, (void));
_PROTOTYPE(int blk_is_used, (block_t blk_num));
_PROTOTYPE(int blk_ok, (block_t num));
_PROTOTYPE(void set_bit, (zone_t num));
_PROTOTYPE(long rd_num, (void));
_PROTOTYPE(int ok, (char *str));
_PROTOTYPE(void done, (int nr));
/* Super block table.
*
* The disk layout is:
*
* Item # block
* boot block 1
* super block 1
* inode map s_imap_blocks
* zone map s_zmap_blocks
* inodes (s_ninodes + 1 + inodes_per_block - 1)/inodes_per_block
* unused
* data zones (s_nzones - s_firstdatazone) << s_log_zone_size
*
*/
#define OK 0
#define NOT_OK 1
#define QUIT 2
#define READ 0
#define WRITE 1
#define HARMLESS 0
#define DIR_CREATED 1
#define DEV_MOUNTED 2
#define FILE_EXISTS 3
#define SUCCESS 4
#define BYTE 0377
#define BLOCK_SIZE 1024
#define SIZE_OF_INT (sizeof (int) )
/* Define V_NR_DZONES as the larger of V1_NR_DZONES and V2_NR_DZONES. */
#if (V1_NR_DZONES > V2_NR_DZONES)
#define V_NR_DZONES V1_NR_DZONES
#define V_SMALLER V2_NR_DZONES
#else
#define V_NR_DZONES V2_NR_DZONES
#define V_SMALLER V1_NR_DZONES
#endif
#if 0
struct super_block {
ino_t s_ninodes; /* # usable inodes on the minor device */
zone1_t s_nzones; /* total device size, including bit maps etc */
short s_imap_blocks; /* # of blocks used by inode bit map */
short s_zmap_blocks; /* # of blocks used by zone bit map */
zone1_t s_firstdatazone; /* number of first data zone */
short s_log_zone_size; /* log2 of blocks/zone */
off_t s_max_size; /* maximum file size on this device */
short s_magic; /* magic number to recognize super-blocks */
short s_pad; /* try to avoid compiler-dependent padding */
zone_t s_zones; /* number of zones (replaces s_nzones in V2) */
} super_block;
#endif
/* ====== globals ======= */
char *dev_name;
char f_name[] = ".Bad_XXXXXX";
char file_name[50];
char dir_name[] = "/tmpXXXXXX";
block_t block[V_NR_DZONES + 1]; /* last block contains zero */
int interactive; /* 1 if interactive (argc == 2) */
int position = 2; /* next block # is argv[position] */
FILE *f;
int fd;
int eofseen; /* set if '\n' seen */
struct stat stat_buf;
struct super_block *sp, sbs;
int inodes_per_block;
size_t inode_size;
int v1fs = 0, v2fs = 0; /* TRUE for V1 file system, FALSE for V2 */
d1_inode d1inode; /* declare a V1 disk inode */
d1_inode *ip1;
d2_inode d2inode; /* declare a V2 disk inode */
d2_inode *ip2;
/* ====== super block routines ======= */
void rw_super(flag)
int flag;
{ /* read or write a superblock */
int rwd;
lseek(fd, 0L, SEEK_SET); /* rewind */
lseek(fd, (long) BLOCK_SIZE, SEEK_SET); /* seek */
if (flag == READ)
rwd = read(fd, (char *) sp, SUPER_SIZE);
else
rwd = write(fd, (char *) sp, SUPER_SIZE);
if (rwd != SUPER_SIZE) { /* ok ? */
printf("Bad %s in get_super() (should be %u is %d)\n",
flag == READ ? "read" : "write",
(unsigned) SUPER_SIZE, rwd);
done(DIR_CREATED);
}
}
void get_super()
/* Get super_block. global pointer sp is used */
{
rw_super(READ);
if (sp->s_magic == SUPER_MAGIC) {
/* This is a V1 file system. */
v1fs = 1; /* file system is not V2 */
} else if (sp->s_magic == SUPER_V2) {
/* This is a V2 file system. */
v2fs = 1; /* this is a V2 file system */
} else if (sp->s_magic == SUPER_V3) {
v1fs = v2fs = 0; /* this is a V3 file system */
} else {
/* Neither V1 nor V2 nor V3. */
printf("Bad magic number in super_block (0x%x)\n",
(unsigned) sp->s_magic);
done(DIR_CREATED);
}
}
void put_super()
{
rw_super(WRITE);
}
/* ========== inode routines =========== */
void rw_inode(stat_ptr, rw_mode)
struct stat *stat_ptr;
int rw_mode;
{
int rwd;
ino_t i_num;
block_t blk, offset;
i_num = stat_ptr->st_ino;
blk = (block_t) (2 + sp->s_imap_blocks + sp->s_zmap_blocks);
blk += (block_t) ((i_num - 1) / inodes_per_block);
blk *= (block_t) (BLOCK_SIZE);/* this block */
offset = (block_t) ((i_num - 1) % inodes_per_block);
offset *= (block_t) (inode_size); /* and this offset */
lseek(fd, (off_t) 0, SEEK_SET); /* rewind */
lseek(fd, (off_t) (blk + offset), SEEK_SET); /* seek */
/* Pointer is at the inode */
if (v1fs) {
/* This is a V1 file system. */
if (rw_mode == READ) { /* read it */
rwd = read(fd, (char *) ip1, inode_size);
} else { /* write it */
rwd = write(fd, (char *) ip1, inode_size);
}
} else {
/* This is a V2 file system. */
if (rw_mode == READ) { /* read it */
rwd = read(fd, (char *) ip2, inode_size);
} else { /* write it */
rwd = write(fd, (char *) ip2, inode_size);
}
}
if (rwd != inode_size) { /* ok ? */
printf("Bad %s in get_inode()\n", (rw_mode == READ) ? "read" :
"write");
done(DIR_CREATED);
}
}
void get_inode(stat_ptr)
struct stat *stat_ptr;
{
int cnt;
rw_inode(stat_ptr, READ);
if (v1fs) {
for (cnt = 0; cnt < V1_NR_TZONES; cnt++)
ip1->d1_zone[cnt] = 0; /* Just to be safe */
} else {
for (cnt = 0; cnt < V2_NR_TZONES; cnt++)
ip2->d2_zone[cnt] = 0; /* Just to be safe */
}
}
void put_inode(stat_ptr)
struct stat *stat_ptr;
{
rw_inode(stat_ptr, WRITE);
}
/* ============== main program ================= */
int main(argc, argv)
int argc;
char *argv[];
{
int cnt, finished;
block_t blk_nr;
struct stat dev_stat;
FILE *fp;
int block_size;
sp = &sbs;
ip1 = &d1inode;
ip2 = &d2inode;
if (argc < 2 || argc > 9) {
fprintf(stderr, "Usage: %s block_special [up_to_7_blocks]\n", argv[0]);
done(HARMLESS);
}
interactive = (argc == 2 ? 1 : 0);
/* Do some test. */
if (geteuid()) {
printf("Sorry, not in superuser mode \n");
printf("Set_uid bit must be on or you must become super_user\n");
done(HARMLESS);
}
dev_name = argv[1];
mktemp(dir_name);
if (mkdir(dir_name, 0777) == -1) {
fprintf(stderr, "%s is already used in system\n", dir_name);
done(HARMLESS);
}
/* Mount device. This call may fail. */
mount(dev_name, dir_name, 0, NULL, NULL);
/* Succes. dev was mounted, try to umount */
/* Umount device. Playing with the file system while other processes
* have access to this device is asking for trouble */
if (umount(dev_name) == -1) {
printf("Could not umount device %s.\n", dev_name);
done(HARMLESS);
}
mktemp(f_name);
/* Create "/tmpXXXXpid/.BadXXpid" */
strcat(file_name, dir_name);
strcat(file_name, "/");
strcat(file_name, f_name);
if (mount(dev_name, dir_name, 0, NULL, NULL) == -1) { /* this call should work */
fprintf(stderr, "Could not mount device anymore\n");
done(HARMLESS);
}
if (stat(file_name, &stat_buf) != -1) {
printf("File %s already exists\n", file_name);
done(DEV_MOUNTED);
}
if ((fp = fopen(file_name, "w")) == NULL) {
printf("Cannot create file %s\n", file_name);
done(DEV_MOUNTED);
}
chmod(file_name, 0); /* "useless" file */
if (stat(file_name, &stat_buf) == -1) {
printf("What? Second call from stat failed\n");
done(FILE_EXISTS);
}
/* Stat buf must be safed. We can now calculate the inode on disk */
fclose(fp);
/* ===== the badblock file is created ===== */
if (umount(dev_name) == -1) {
printf("Can not umount device anymore??? \n");
done(DIR_CREATED);
}
if ((fd = open(dev_name, O_RDWR)) == -1) {
printf("Can not open device %s\n", dev_name);
done(DEV_MOUNTED);
}
if (fstat(fd, &dev_stat) == -1) {
printf("fstat on device %s failed\n", dev_name);
done(DEV_MOUNTED);
}
if ((dev_stat.st_mode & S_IFMT) != S_IFBLK) {
printf("Device \"%s\" is not a block_special.\n", dev_name);
done(DEV_MOUNTED);
}
get_super();
if (sp->s_log_zone_size) {
printf("Block_size != zone_size.");
printf("This program can not handle it\n");
done(DIR_CREATED);
}
if(v1fs || v2fs) block_size = 1024;
else block_size = sp->s_block_size;
/* The number of inodes in a block differs in V1 and V2. */
if (v1fs) {
inodes_per_block = V1_INODES_PER_BLOCK;
inode_size = V1_INODE_SIZE;
} else {
inodes_per_block = V2_INODES_PER_BLOCK(block_size);
inode_size = V2_INODE_SIZE;
}
get_inode(&stat_buf);
for (finished = 0; !finished;) {
if (interactive)
printf("Give up to %d bad block numbers separated by spaces\n",
V_SMALLER);
reset_blks();
cnt = 0; /* cnt keep track of the zone's */
while (cnt < V_SMALLER) {
int tst;
if (interactive)
blk_nr = rd_num();
else
blk_nr = rd_cmdline(argc, argv);
if (blk_nr == -1) break;
tst = blk_ok(blk_nr);
/* Test if this block is free */
if (tst == OK) {
cnt++;
save_blk(blk_nr);
} else if (tst == QUIT)
break;
}
if (interactive) show_blks();
if (!cnt) done(FILE_EXISTS);
if (interactive) {
switch (ok("All these blocks ok <y/n/q> (y:Device will change) ")) {
case OK: finished = 1; break;
case NOT_OK:
break;
case QUIT: done(FILE_EXISTS);
}
} else {
finished = 1;
}
}
modify(cnt);
close(fd); /* free device */
done(SUCCESS);
return(0);
}
long rd_cmdline(argc, argv)
int argc;
char *argv[];
{
if (position == argc) return(-1);
return(atol(argv[position++]));
}
void modify(nr_blocks)
int nr_blocks;
{
int i;
if (nr_blocks == 0) return;
if (v1fs) {
/* This is a V1 file system. */
for (i = 0; i < nr_blocks; i++) {
set_bit(block[i]);
ip1->d1_zone[i] = block[i];
}
} else {
/* This is a V2 file system. */
for (i = 0; i < nr_blocks; i++) {
set_bit(block[i]);
ip2->d2_zone[i] = block[i];
}
}
if (v1fs) {
ip1->d1_size = (long) (BLOCK_SIZE * nr_blocks); /* give file size */
ip1->d1_mtime = 0; /* Who wants a file from 1970? */
} else {
ip2->d2_size = (long) (BLOCK_SIZE * nr_blocks); /* give file size */
ip2->d2_atime = ip2->d2_mtime = ip2->d2_ctime = 0;
}
put_inode(&stat_buf); /* save the inode on disk */
put_super(); /* bit_maps too */
}
static blk_cnt = 0;
void save_blk(blk_num)
block_t blk_num;
{
block[blk_cnt++] = blk_num;
}
void reset_blks()
{
int i;
for (i = 0; i <= V_NR_DZONES; i++)
block[i] = 0; /* Note: Last block_number is set to zero */
blk_cnt = 0;
}
void show_blks()
{
int i;
for (i = 0; i < blk_cnt; i++)
printf("Block[%d] = %lu\n", i, (unsigned long) block[i]);
}
int blk_is_used(blk_num)
block_t blk_num;
{ /* return TRUE(1) if used */
int i;
for (i = 0; block[i] && block[i] != blk_num; i++);
return(block[i] != 0) ? 1 : 0;
}
/* ===== bitmap handling ====== */
#define BIT_MAP_SHIFT 13
#define INT_BITS (SIZE_OF_INT << 3)
int blk_ok(num) /* is this zone free (y/n) */
block_t num;
{
block_t blk_offset;
int rd;
int blk, offset, words, bit, tst_word;
zone_t z_num;
if (blk_is_used(num)) {
printf("Duplicate block (%lu) given\n", (unsigned long) num);
return NOT_OK;
}
/* Assumption zone_size == block_size */
z_num = num - (sp->s_firstdatazone - 1); /* account offset */
/* Calculate the word in the bitmap. */
blk = z_num >> BIT_MAP_SHIFT; /* which block */
offset = z_num - (blk << BIT_MAP_SHIFT); /* offset */
words = z_num / INT_BITS; /* which word */
blk_offset = (block_t) (2 + sp->s_imap_blocks); /* zone map */
blk_offset *= (block_t) BLOCK_SIZE; /* of course in block */
blk_offset += (block_t) (words * SIZE_OF_INT); /* offset */
lseek(fd, (off_t) 0, SEEK_SET); /* rewind */
lseek(fd, (off_t) blk_offset, SEEK_SET); /* set pointer at word */
rd = read(fd, (char *) &tst_word, SIZE_OF_INT);
if (rd != SIZE_OF_INT) {
printf("Read error in bitmap\n");
done(DIR_CREATED);
}
/* We have the tst_word, check if bit was off */
bit = offset % INT_BITS;
if (((tst_word >> bit) & 01) == 0) /* free */
return OK;
else {
printf("Bad number %lu. ", (unsigned long) num);
printf("This zone (block) is marked in bitmap\n");
return NOT_OK;
}
}
void set_bit(num) /* write in the bitmap */
zone_t num;
{
int rwd;
long blk_offset;
int blk, offset, words, tst_word, bit;
unsigned z_num;
z_num = num - (sp->s_firstdatazone - 1);
blk = z_num >> BIT_MAP_SHIFT; /* which block */
offset = z_num - (blk << BIT_MAP_SHIFT); /* offset in block */
words = z_num / INT_BITS; /* which word */
blk_offset = (long) (2 + sp->s_imap_blocks);
blk_offset *= (long) BLOCK_SIZE;
blk_offset += (long) (words * SIZE_OF_INT);
lseek(fd, (off_t) 0, SEEK_SET); /* rewind */
lseek(fd, (off_t) blk_offset, SEEK_SET);
rwd = read(fd, (char *) &tst_word, SIZE_OF_INT);
if (rwd != SIZE_OF_INT) {
printf("Read error in bitmap\n");
done(DEV_MOUNTED);
}
bit = offset % INT_BITS;
if (((tst_word >> bit) & 01) == 0) { /* free */
lseek(fd, 0L, SEEK_SET);/* rewind */
lseek(fd, (off_t) blk_offset, SEEK_SET);
tst_word |= (1 << bit); /* not free anymore */
rwd = write(fd, (char *) &tst_word, SIZE_OF_INT);
if (rwd != SIZE_OF_INT) {
printf("Bad write in zone map\n");
printf("Check file system \n");
done(DIR_CREATED);
}
return;
}
printf("Bit map indicates that block %lu is in use. Not marked.\n",
(unsigned long) num);
/* done(DIR_CREATED); */
return;
}
/* ======= interactive interface ======= */
long rd_num()
{ /* read a number from stdin */
long num;
int c;
if (eofseen) return(-1);
do {
c = getchar();
if (c == EOF || c == '\n') return(-1);
} while (c != '-' && (c < '0' || c > '9'));
if (c == '-') {
printf("Block numbers must be positive\n");
exit(1);
}
num = 0;
while (c >= '0' && c <= '9') {
num *= 10;
num += c - '0';
c = getchar();
if (c == '\n') eofseen = 1;
}
return num;
}
int ok(str)
char *str;
{
int c;
for (;;) {
printf("%s", str);
while ((c = getchar()) != EOF &&
c != 'y' && c != 'n' && c != 'q')
if (c != '\n') printf(" Bad character %c\n", (char) c);
switch (c) {
case EOF:
return QUIT;
case 'y':
return OK;
case 'n':
return NOT_OK;
case 'q': return QUIT;
}
printf("\n");
}
}
void done(nr)
int nr;
{
switch (nr) {
case SUCCESS:
case FILE_EXISTS:
unlink(file_name);
case DEV_MOUNTED:
umount(dev_name);
case DIR_CREATED:
rmdir(dir_name);
case HARMLESS:;
}
sync();
exit(nr == SUCCESS ? 0 : 1);
}