e2fsprogs/e2fsck/pass1b.c

597 lines
14 KiB
C

/*
* 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, 1995, 1996, 1997 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %End-Header%
*
*/
#include <time.h>
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#include <et/com_err.h>
#include "e2fsck.h"
#include "problem.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, dir;
int num_dupblocks;
struct ext2_inode inode;
struct dup_inode *next;
};
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;
static ext2fs_inode_bitmap 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,
"multiply claimed inode map", &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.
*/
ext2fs_free_inode_bitmap(inode_dup_map); inode_dup_map = 0;
ext2fs_free_block_bitmap(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;
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(inode_used_map, ino) ||
!ext2fs_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->dir = 0;
dp->inode = inode;
dp->num_dupblocks = pb.dup_blocks;
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(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 %lu:",
p->ino);
printf(" %u", *block_nr);
}
p->dup_blocks++;
ext2fs_mark_block_bitmap(block_dup_map, *block_nr);
ext2fs_mark_inode_bitmap(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;
}
/*
* 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 search_dir_struct {
int count;
ino_t first_inode;
};
static int search_dirent_proc(ino_t dir, int entry,
struct ext2_dir_entry *dirent,
int offset, int blocksize,
char *buf, void *private)
{
struct search_dir_struct *sd = private;
struct dup_inode *p;
if (!dirent->inode || (entry < DIRENT_OTHER_FILE) ||
!ext2fs_test_inode_bitmap(inode_dup_map, dirent->inode))
return 0;
for (p = dup_ino; p; p = p->next) {
if ((p->ino >= sd->first_inode) &&
(p->ino == dirent->inode))
break;
}
if (!p || p->dir)
return 0;
p->dir = dir;
sd->count--;
return(sd->count ? 0 : DIRENT_ABORT);
}
void pass1c(ext2_filsys fs, char *block_buf)
{
struct dup_inode *p;
int inodes_left = dup_inode_count;
struct search_dir_struct sd;
printf("Pass 1C: Scan directories for inodes with dup blocks.\n");
/*
* First check to see if any of the inodes with dup blocks is
* a special inode. (Note that the bad block inode isn't
* counted.)
*/
for (p = dup_ino; p; p = p->next) {
if ((p->ino < EXT2_FIRST_INODE(fs->super)) &&
(p->ino != EXT2_BAD_INO))
inodes_left--;
}
/*
* Search through all directories to translate inodes to names
* (by searching for the containing directory for that inode.)
*/
sd.count = inodes_left;
sd.first_inode = EXT2_FIRST_INODE(fs->super);
ext2fs_dblist_dir_iterate(fs->dblist, 0, block_buf,
search_dirent_proc, &sd);
}
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;
int file_ok;
struct problem_context pctx;
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;
}
}
}
/*
* Report the inode that we are working on
*/
clear_problem_context(&pctx);
pctx.inode = &p->inode;
pctx.ino = p->ino;
pctx.dir = p->dir;
pctx.blkcount = p->num_dupblocks;
pctx.num = shared_len;
fix_problem(fs, PR_1B_DUP_FILE, &pctx);
pctx.blkcount = 0;
pctx.num = 0;
for (i = 0; i < shared_len; i++) {
for (s = dup_ino; s; s = s->next)
if (s->ino == shared[i])
break;
if (!s)
continue;
/*
* Report the inode that we are sharing with
*/
pctx.inode = &s->inode;
pctx.ino = s->ino;
pctx.dir = s->dir;
fix_problem(fs, PR_1B_DUP_FILE_LIST, &pctx);
}
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");
}
free(shared);
}
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(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(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(block_found_map, *block_nr);
ext2fs_unmark_block_bitmap(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(inode_used_map, dp->ino);
ext2fs_unmark_inode_bitmap(inode_dir_map, dp->ino);
if (inode_bad_map)
ext2fs_unmark_inode_bitmap(inode_bad_map, dp->ino);
ext2fs_unmark_inode_bitmap(fs->inode_map, dp->ino);
ext2fs_mark_ib_dirty(fs);
ext2fs_mark_bb_dirty(fs);
e2fsck_read_inode(fs, dp->ino, &inode, "delete_file");
inode.i_links_count = 0;
inode.i_dtime = time(0);
e2fsck_write_inode(fs, dp->ino, &inode, "delete_file");
}
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(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(block_dup_map,
*block_nr);
*block_nr = new_block;
ext2fs_mark_block_bitmap(block_found_map,
new_block);
ext2fs_mark_block_bitmap(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;
}