e2fsprogs/e2fsck/pass1b.c

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1997-04-26 21:21:57 +08:00
/*
* pass1b.c --- Pass #1b of e2fsck
*
* This file contains pass1B, pass1C, and pass1D of e2fsck. They are
* only invoked if pass 1 discovered blocks which are in use by more
* than one inode.
*
* Pass1B scans the data blocks of all the inodes again, generating a
* complete list of duplicate blocks and which inodes have claimed
* them.
*
* Pass1C does a tree-traversal of the filesystem, to determine the
* parent directories of these inodes. This step is necessary so that
* e2fsck can print out the pathnames of affected inodes.
*
* Pass1D is a reconciliation pass. For each inode with duplicate
* blocks, the user is prompted if s/he would like to clone the file
* (so that the file gets a fresh copy of the duplicated blocks) or
* simply to delete the file.
*
* Copyright (C) 1993, 1994 Theodore Ts'o. This file may be
* redistributed under the terms of the GNU Public License.
*
*/
#include <time.h>
#include <et/com_err.h>
#include "e2fsck.h"
/*
* This is structure is allocated for each time that a block is
* claimed by more than one file. So if a particular block is claimed
* by 3 files, then three copies of this structure will be allocated,
* one for each conflict.
*
* The linked list structure is as follows:
*
* dup_blk --> block #34 --> block #35 --> block #47
* inode #12 inode #14 inode #17
* num_bad = 3 num_bad = 2 num_bad = 2
* | | |
* V V V
* block #34 block #35 block #47
* inode #14 inode #15 inode #23
* |
* V
* block #34
* inode #15
*
* The num_bad field indicates how many inodes are sharing a
* particular block, and is only stored in the first element of the
* linked list for a particular block. As the block conflicts are
* resolved, num_bad is decremented; when it reaches 1, then we no
* longer need to worry about that block.
*/
struct dup_block {
blk_t block; /* Block number */
ino_t ino; /* Inode number */
int num_bad;
/* Pointer to next dup record with different block */
struct dup_block *next_block;
/* Pointer to next dup record with different inode */
struct dup_block *next_inode;
};
/*
* This structure stores information about a particular inode which
* is sharing blocks with other inodes. This information is collected
* to display to the user, so that the user knows what files he or she
* is dealing with, when trying to decide how to resolve the conflict
* of multiply-claimed blocks.
*/
struct dup_inode {
ino_t ino;
time_t mtime;
char *pathname;
int num_dupblocks;
int flags;
struct dup_inode *next;
};
#define DUP_INODE_DONT_FREE_PATHNAME 0x1
static int process_pass1b_block(ext2_filsys fs, blk_t *blocknr,
int blockcnt, void *private);
static void delete_file(ext2_filsys fs, struct dup_inode *dp,
char *block_buf);
static int clone_file(ext2_filsys fs, struct dup_inode *dp, char* block_buf);
static void pass1b(ext2_filsys fs, char *block_buf);
static void pass1c(ext2_filsys fs, char *block_buf);
static void pass1d(ext2_filsys fs, char *block_buf);
static struct dup_block *dup_blk = 0;
static struct dup_inode *dup_ino = 0;
static int dup_inode_count = 0;
/*
* For pass1_check_directory and pass1_get_blocks
*/
extern ino_t stashed_ino;
extern struct ext2_inode *stashed_inode;
static char *inode_dup_map;
/*
* Main procedure for handling duplicate blocks
*/
void pass1_dupblocks(ext2_filsys fs, char *block_buf)
{
errcode_t retval;
struct dup_block *p, *q, *next_p, *next_q;
struct dup_inode *r, *next_r;
retval = ext2fs_allocate_inode_bitmap(fs, &inode_dup_map);
if (retval) {
com_err("ext2fs_allocate_inode_bitmap", retval,
"while allocating inode_dup_map");
fatal_error(0);
}
pass1b(fs, block_buf);
pass1c(fs, block_buf);
pass1d(fs, block_buf);
/*
* Time to free all of the accumulated data structures that we
* don't need anymore.
*/
free(inode_dup_map); inode_dup_map = 0;
free(block_dup_map); block_dup_map = 0;
for (p = dup_blk; p; p = next_p) {
next_p = p->next_block;
for (q = p; q; q = next_q) {
next_q = q->next_inode;
free(q);
}
}
for (r = dup_ino; r; r = next_r) {
next_r = r->next;
if (r->pathname && !(r->flags & DUP_INODE_DONT_FREE_PATHNAME))
free(r->pathname);
free(r);
}
}
/*
* Scan the inodes looking for inodes that contain duplicate blocks.
*/
struct process_block_struct {
ino_t ino;
int dup_blocks;
};
void pass1b(ext2_filsys fs, char *block_buf)
{
ino_t ino;
struct ext2_inode inode;
ext2_inode_scan scan;
errcode_t retval;
struct process_block_struct pb;
struct dup_inode *dp;
printf("Duplicate blocks found... invoking duplicate block passes.\n");
printf("Pass 1B: Rescan for duplicate/bad blocks\n");
retval = ext2fs_open_inode_scan(fs, inode_buffer_blocks, &scan);
if (retval) {
com_err(program_name, retval, "while opening inode scan");
fatal_error(0);
}
retval = ext2fs_get_next_inode(scan, &ino, &inode);
if (retval) {
com_err(program_name, retval, "while starting inode scan");
fatal_error(0);
}
stashed_inode = &inode;
while (ino) {
stashed_ino = ino;
if ((ino != EXT2_BAD_INO) &&
(!ext2fs_test_inode_bitmap(fs, inode_used_map, ino) ||
!inode_has_valid_blocks(&inode)))
goto next;
pb.ino = ino;
pb.dup_blocks = 0;
retval = ext2fs_block_iterate(fs, ino, 0, block_buf,
process_pass1b_block, &pb);
if (pb.dup_blocks) {
if (ino != EXT2_BAD_INO)
printf("\n");
dp = allocate_memory(sizeof(struct dup_inode),
"duplicate inode record");
dp->ino = ino;
dp->mtime = inode.i_mtime;
dp->num_dupblocks = pb.dup_blocks;
dp->pathname = 0;
dp->flags = 0;
dp->next = dup_ino;
dup_ino = dp;
if (ino != EXT2_BAD_INO)
dup_inode_count++;
}
if (retval)
com_err(program_name, retval,
"while calling ext2fs_block_iterate in pass1b");
next:
retval = ext2fs_get_next_inode(scan, &ino, &inode);
if (retval) {
com_err(program_name, retval,
"while doing inode scan");
fatal_error(0);
}
}
ext2fs_close_inode_scan(scan);
fs->get_blocks = 0;
fs->check_directory = 0;
}
int process_pass1b_block(ext2_filsys fs,
blk_t *block_nr,
int blockcnt,
void *private)
{
struct process_block_struct *p;
struct dup_block *dp, *q, *r;
int i;
if (!*block_nr)
return 0;
p = (struct process_block_struct *) private;
if (ext2fs_test_block_bitmap(fs, block_dup_map, *block_nr)) {
/* OK, this is a duplicate block */
if (p->ino != EXT2_BAD_INO) {
if (!p->dup_blocks)
printf("Duplicate/bad block(s) in inode %ld:",
p->ino);
printf(" %ld", *block_nr);
}
p->dup_blocks++;
ext2fs_mark_block_bitmap(fs, block_dup_map, *block_nr);
ext2fs_mark_inode_bitmap(fs, inode_dup_map, p->ino);
dp = allocate_memory(sizeof(struct dup_block),
"duplicate block record");
dp->block = *block_nr;
dp->ino = p->ino;
dp->num_bad = 0;
q = dup_blk;
while (q) {
if (q->block == *block_nr)
break;
q = q->next_block;
}
if (q) {
dp->next_inode = q->next_inode;
q->next_inode = dp;
} else {
dp->next_block = dup_blk;
dup_blk = dp;
}
}
/*
* Set the num_bad field
*/
for (q = dup_blk; q; q = q->next_block) {
i = 0;
for (r = q; r; r = r->next_inode)
i++;
q->num_bad = i;
}
return 0;
}
/*
* Used by pass1c to name the "special" inodes. They are declared as
* writeable strings to prevent const problems.
*/
#define num_special_inodes 7
char special_inode_name[num_special_inodes][40] =
{
"<The NULL inode>", /* 0 */
"<The bad blocks inode>", /* 1 */
"/", /* 2 */
"<The ACL index inode>", /* 3 */
"<The ACL data inode>", /* 4 */
"<The boot loader inode>", /* 5 */
"<The undelete directory inode>" /* 6 */
};
/*
* Pass 1c: Scan directories for inodes with duplicate blocks. This
* is used so that we can print pathnames when prompting the user for
* what to do.
*/
struct process_dir_struct {
ext2_filsys fs;
ino_t dir_ino;
int count;
};
void pass1c(ext2_filsys fs, char *block_buf)
{
int i;
struct dup_inode *p;
errcode_t retval;
char buf[80];
int inodes_left = dup_inode_count;
int offset, entry;
struct ext2_dir_entry *dirent;
printf("Pass 1C: Scan directories for inodes with dup blocks.\n");
/*
* First check to see if any of the inodes with dup blocks is
* the bad block inode or the root inode; handle them as
* special cases.
*/
for (p = dup_ino; p; p = p->next) {
if (p->ino < num_special_inodes) {
p->pathname = special_inode_name[p->ino];
p->flags |= DUP_INODE_DONT_FREE_PATHNAME;
inodes_left--;
}
}
/*
* Search through all directories to translate inodes to names
* (by searching for the containing directory for that inode.)
*/
for (i=0; inodes_left && i < dir_block_count; i++) {
retval = io_channel_read_blk(fs->io, dir_blocks[i].blk,
1, block_buf);
entry = offset = 0;
while (offset < fs->blocksize) {
entry++;
dirent = (struct ext2_dir_entry *)
(block_buf + offset);
if (!dirent->inode ||
((dir_blocks[i].blockcnt == 0) && (entry <= 2)))
goto next;
if (!ext2fs_test_inode_bitmap(fs, inode_dup_map,
dirent->inode))
goto next;
for (p = dup_ino; p; p = p->next) {
if (p->ino == dirent->inode)
break;
}
if (!p || p->pathname)
goto next;
(void) ext2fs_get_pathname(fs, dir_blocks[i].ino,
p->ino, &p->pathname);
inodes_left--;
next:
if (dirent->rec_len < 8)
break;
offset += dirent->rec_len;
}
}
/*
* If we can't get a name, then put in a generic one.
*/
for (p = dup_ino; p; p = p->next) {
if (!p->pathname) {
sprintf(buf, "<Unknown inode #%ld>", p->ino);
p->pathname = malloc(strlen(buf)+1);
if (!p->pathname) {
fprintf(stderr, "pass1c: couldn't malloc "
"generic pathname\n");
fatal_error(0);
}
strcpy(p->pathname, buf);
}
}
}
static void pass1d(ext2_filsys fs, char *block_buf)
{
struct dup_inode *p, *s;
struct dup_block *q, *r;
ino_t *shared;
int shared_len;
int i;
errcode_t retval;
char *time_str;
int file_ok;
printf("Pass 1D: Reconciling duplicate blocks\n");
read_bitmaps(fs);
printf("(There are %d inodes containing duplicate/bad blocks.)\n\n",
dup_inode_count);
shared = allocate_memory(sizeof(ino_t) * dup_inode_count,
"Shared inode list");
for (p = dup_ino; p; p = p->next) {
shared_len = 0;
file_ok = 1;
if (p->ino == EXT2_BAD_INO)
continue;
/*
* Search through the duplicate records to see which
* inodes share blocks with this one
*/
for (q = dup_blk; q; q = q->next_block) {
/*
* See if this block is used by this inode.
* If it isn't, continue.
*/
for (r = q; r; r = r->next_inode)
if (r->ino == p->ino)
break;
if (!r)
continue;
if (q->num_bad > 1)
file_ok = 0;
/*
* Add all inodes used by this block to the
* shared[] --- which is a unique list, so
* if an inode is already in shared[], don't
* add it again.
*/
for (r = q; r; r = r->next_inode) {
if (r->ino == p->ino)
continue;
for (i = 0; i < shared_len; i++)
if (shared[i] == r->ino)
break;
if (i == shared_len) {
shared[shared_len++] = r->ino;
}
}
}
time_str = ctime(&p->mtime);
time_str[24] = 0;
printf("File %s (inode #%ld, mod time %s) \n",
p->pathname, p->ino, time_str);
printf(" has %d duplicate blocks, shared with %d file%s:\n",
p->num_dupblocks, shared_len,
(shared_len>1) ? "s" : "");
for (i = 0; i < shared_len; i++) {
for (s = dup_ino; s; s = s->next)
if (s->ino == shared[i])
break;
if (!s)
continue;
time_str = ctime(&s->mtime);
time_str[24] = 0;
printf("\t%s (inode #%ld, mod time %s)\n",
s->pathname, s->ino, time_str);
}
if (file_ok) {
printf("Duplicated blocks already reassigned or cloned.\n\n");
continue;
}
if (ask("Clone duplicate/bad blocks", 1)) {
retval = clone_file(fs, p, block_buf);
if (retval)
printf("Couldn't clone file: %s\n",
error_message(retval));
else {
printf("\n");
continue;
}
}
if (ask("Delete file", 1))
delete_file(fs, p, block_buf);
else
ext2fs_unmark_valid(fs);
printf("\n");
}
}
static int delete_file_block(ext2_filsys fs,
blk_t *block_nr,
int blockcnt,
void *private)
{
struct dup_block *p;
if (!*block_nr)
return 0;
if (ext2fs_test_block_bitmap(fs, block_dup_map, *block_nr)) {
for (p = dup_blk; p; p = p->next_block)
if (p->block == *block_nr)
break;
if (p) {
p->num_bad--;
if (p->num_bad == 1)
ext2fs_unmark_block_bitmap(fs, block_dup_map,
*block_nr);
} else
com_err("delete_file_block", 0,
"internal error; can't find dup_blk for %d\n",
*block_nr);
} else {
ext2fs_unmark_block_bitmap(fs, block_found_map, *block_nr);
ext2fs_unmark_block_bitmap(fs, fs->block_map, *block_nr);
}
return 0;
}
static void delete_file(ext2_filsys fs, struct dup_inode *dp, char* block_buf)
{
errcode_t retval;
struct process_block_struct pb;
struct ext2_inode inode;
pb.ino = dp->ino;
pb.dup_blocks = dp->num_dupblocks;
retval = ext2fs_block_iterate(fs, dp->ino, 0, block_buf,
delete_file_block, &pb);
if (retval)
com_err("delete_file", retval,
"while calling ext2fs_block_iterate for inode %d",
dp->ino);
ext2fs_unmark_inode_bitmap(fs, inode_used_map, dp->ino);
ext2fs_unmark_inode_bitmap(fs, inode_dir_map, dp->ino);
if (inode_bad_map)
ext2fs_unmark_inode_bitmap(fs, inode_bad_map, dp->ino);
ext2fs_unmark_inode_bitmap(fs, fs->inode_map, dp->ino);
ext2fs_mark_ib_dirty(fs);
ext2fs_mark_bb_dirty(fs);
retval = ext2fs_read_inode(fs, dp->ino, &inode);
if (retval) {
com_err("delete_file", retval, "while reading inode %d",
dp->ino);
return;
}
inode.i_links_count = 0;
inode.i_dtime = time(0);
retval = ext2fs_write_inode(fs, dp->ino, &inode);
if (retval) {
com_err("delete_file", retval, "while writing inode %d",
dp->ino);
return;
}
}
struct clone_struct {
errcode_t errcode;
char *buf;
};
static int clone_file_block(ext2_filsys fs,
blk_t *block_nr,
int blockcnt,
void *private)
{
struct dup_block *p;
blk_t new_block;
errcode_t retval;
struct clone_struct *cs = (struct clone_struct *) private;
if (!*block_nr)
return 0;
if (ext2fs_test_block_bitmap(fs, block_dup_map, *block_nr)) {
for (p = dup_blk; p; p = p->next_block)
if (p->block == *block_nr)
break;
if (p) {
retval = ext2fs_new_block(fs, 0, block_found_map,
&new_block);
if (retval) {
cs->errcode = retval;
return BLOCK_ABORT;
}
retval = io_channel_read_blk(fs->io, *block_nr, 1,
cs->buf);
if (retval) {
cs->errcode = retval;
return BLOCK_ABORT;
}
retval = io_channel_write_blk(fs->io, new_block, 1,
cs->buf);
if (retval) {
cs->errcode = retval;
return BLOCK_ABORT;
}
p->num_bad--;
if (p->num_bad == 1)
ext2fs_unmark_block_bitmap(fs, block_dup_map,
*block_nr);
*block_nr = new_block;
ext2fs_mark_block_bitmap(fs, block_found_map,
new_block);
ext2fs_mark_block_bitmap(fs, fs->block_map, new_block);
return BLOCK_CHANGED;
} else
com_err("clone_file_block", 0,
"internal error; can't find dup_blk for %d\n",
*block_nr);
}
return 0;
}
static int clone_file(ext2_filsys fs, struct dup_inode *dp, char* block_buf)
{
errcode_t retval;
struct clone_struct cs;
cs.errcode = 0;
cs.buf = malloc(fs->blocksize);
if (!cs.buf)
return ENOMEM;
retval = ext2fs_block_iterate(fs, dp->ino, 0, block_buf,
clone_file_block, &cs);
ext2fs_mark_bb_dirty(fs);
free(cs.buf);
if (retval) {
com_err("clone_file", retval,
"while calling ext2fs_block_iterate for inode %d",
dp->ino);
return retval;
}
if (cs.errcode) {
com_err("clone_file", retval,
"returned from clone_file_block");
return retval;
}
return 0;
}