Fix typos in code comments and developer docs

[thirdparty/e2fsprogs.git] / e2fsck / pass1b.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 "config.h"
#include <time.h>
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif

#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif

#ifndef HAVE_INTPTR_T
typedef long intptr_t;
#endif

/* Needed for architectures where sizeof(int) != sizeof(void *) */
#define INT_TO_VOIDPTR(val)  ((void *)(intptr_t)(val))
#define VOIDPTR_TO_INT(ptr)  ((int)(intptr_t)(ptr))

#include <et/com_err.h>
#include "e2fsck.h"

#include "problem.h"
#include "support/dict.h"

/* Define an extension to the ext2 library's block count information */
#define BLOCK_COUNT_EXTATTR     (-5)

struct cluster_el {
        blk64_t cluster;
        struct cluster_el *next;
};

struct inode_el {
        ext2_ino_t      inode;
        struct inode_el *next;
};

struct dup_cluster {
        int             num_bad;
        struct inode_el *inode_list;
};

/*
 * 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 {
        ext2_ino_t              dir;
        int                     num_dupblocks;
        struct ext2_inode_large inode;
        struct cluster_el       *cluster_list;
};

static int process_pass1b_block(ext2_filsys fs, blk64_t *blocknr,
                                e2_blkcnt_t blockcnt, blk64_t ref_blk,
                                int ref_offset, void *priv_data);
static void delete_file(e2fsck_t ctx, ext2_ino_t ino,
                        struct dup_inode *dp, char *block_buf);
static errcode_t clone_file(e2fsck_t ctx, ext2_ino_t ino,
                            struct dup_inode *dp, char* block_buf);
static int check_if_fs_block(e2fsck_t ctx, blk64_t test_block);
static int check_if_fs_cluster(e2fsck_t ctx, blk64_t cluster);

static void pass1b(e2fsck_t ctx, char *block_buf);
static void pass1c(e2fsck_t ctx, char *block_buf);
static void pass1d(e2fsck_t ctx, char *block_buf);

static int dup_inode_count = 0;
static int dup_inode_founddir = 0;

static dict_t clstr_dict, ino_dict;

static ext2fs_inode_bitmap inode_dup_map;

static int dict_int_cmp(const void *a, const void *b)
{
        intptr_t        ia, ib;

        ia = (intptr_t)a;
        ib = (intptr_t)b;

        return (ia-ib);
}

/*
 * Add a duplicate block record
 */
static void add_dupe(e2fsck_t ctx, ext2_ino_t ino, blk64_t cluster,
                     struct ext2_inode_large *inode)
{
        dnode_t *n;
        struct dup_cluster      *db;
        struct dup_inode        *di;
        struct cluster_el       *cluster_el;
        struct inode_el         *ino_el;

        n = dict_lookup(&clstr_dict, INT_TO_VOIDPTR(cluster));
        if (n)
                db = (struct dup_cluster *) dnode_get(n);
        else {
                db = (struct dup_cluster *) e2fsck_allocate_memory(ctx,
                        sizeof(struct dup_cluster), "duplicate cluster header");
                db->num_bad = 0;
                db->inode_list = 0;
                dict_alloc_insert(&clstr_dict, INT_TO_VOIDPTR(cluster), db);
        }
        ino_el = (struct inode_el *) e2fsck_allocate_memory(ctx,
                         sizeof(struct inode_el), "inode element");
        ino_el->inode = ino;
        ino_el->next = db->inode_list;
        db->inode_list = ino_el;
        db->num_bad++;

        n = dict_lookup(&ino_dict, INT_TO_VOIDPTR(ino));
        if (n)
                di = (struct dup_inode *) dnode_get(n);
        else {
                di = (struct dup_inode *) e2fsck_allocate_memory(ctx,
                         sizeof(struct dup_inode), "duplicate inode header");
                if (ino == EXT2_ROOT_INO) {
                        di->dir = EXT2_ROOT_INO;
                        dup_inode_founddir++;
                } else
                        di->dir = 0;

                di->num_dupblocks = 0;
                di->cluster_list = 0;
                di->inode = *inode;
                dict_alloc_insert(&ino_dict, INT_TO_VOIDPTR(ino), di);
        }
        cluster_el = (struct cluster_el *) e2fsck_allocate_memory(ctx,
                         sizeof(struct cluster_el), "cluster element");
        cluster_el->cluster = cluster;
        cluster_el->next = di->cluster_list;
        di->cluster_list = cluster_el;
        di->num_dupblocks++;
}

/*
 * Free a duplicate inode record
 */
static void inode_dnode_free(dnode_t *node,
                             void *context EXT2FS_ATTR((unused)))
{
        struct dup_inode        *di;
        struct cluster_el               *p, *next;

        di = (struct dup_inode *) dnode_get(node);
        for (p = di->cluster_list; p; p = next) {
                next = p->next;
                free(p);
        }
        free(di);
        free(node);
}

/*
 * Free a duplicate cluster record
 */
static void cluster_dnode_free(dnode_t *node,
                               void *context EXT2FS_ATTR((unused)))
{
        struct dup_cluster      *dc;
        struct inode_el         *p, *next;

        dc = (struct dup_cluster *) dnode_get(node);
        for (p = dc->inode_list; p; p = next) {
                next = p->next;
                free(p);
        }
        free(dc);
        free(node);
}


/*
 * Main procedure for handling duplicate blocks
 */
void e2fsck_pass1_dupblocks(e2fsck_t ctx, char *block_buf)
{
        ext2_filsys             fs = ctx->fs;
        struct problem_context  pctx;
#ifdef RESOURCE_TRACK
        struct resource_track   rtrack;
#endif

        clear_problem_context(&pctx);

        pctx.errcode = e2fsck_allocate_inode_bitmap(fs,
                        _("multiply claimed inode map"),
                        EXT2FS_BMAP64_RBTREE, "inode_dup_map",
                        &inode_dup_map);
        if (pctx.errcode) {
                fix_problem(ctx, PR_1B_ALLOCATE_IBITMAP_ERROR, &pctx);
                ctx->flags |= E2F_FLAG_ABORT;
                return;
        }

        dict_init(&ino_dict, DICTCOUNT_T_MAX, dict_int_cmp);
        dict_init(&clstr_dict, DICTCOUNT_T_MAX, dict_int_cmp);
        dict_set_allocator(&ino_dict, NULL, inode_dnode_free, NULL);
        dict_set_allocator(&clstr_dict, NULL, cluster_dnode_free, NULL);

        init_resource_track(&rtrack, ctx->fs->io);
        pass1b(ctx, block_buf);
        print_resource_track(ctx, "Pass 1b", &rtrack, ctx->fs->io);

        init_resource_track(&rtrack, ctx->fs->io);
        pass1c(ctx, block_buf);
        print_resource_track(ctx, "Pass 1c", &rtrack, ctx->fs->io);

        init_resource_track(&rtrack, ctx->fs->io);
        pass1d(ctx, block_buf);
        print_resource_track(ctx, "Pass 1d", &rtrack, ctx->fs->io);

        /*
         * Time to free all of the accumulated data structures that we
         * don't need anymore.
         */
        dict_free_nodes(&ino_dict);
        dict_free_nodes(&clstr_dict);
        ext2fs_free_inode_bitmap(inode_dup_map);
}

/*
 * Scan the inodes looking for inodes that contain duplicate blocks.
 */
struct process_block_struct {
        e2fsck_t        ctx;
        ext2_ino_t      ino;
        int             dup_blocks;
        blk64_t         cur_cluster, phys_cluster;
        blk64_t         last_blk;
        struct ext2_inode_large *inode;
        struct problem_context *pctx;
};

static void pass1b(e2fsck_t ctx, char *block_buf)
{
        ext2_filsys fs = ctx->fs;
        ext2_ino_t ino = 0;
        struct ext2_inode_large inode;
        ext2_inode_scan scan;
        struct process_block_struct pb;
        struct problem_context pctx;
        problem_t op;

        clear_problem_context(&pctx);

        if (!(ctx->options & E2F_OPT_PREEN))
                fix_problem(ctx, PR_1B_PASS_HEADER, &pctx);
        pctx.errcode = ext2fs_open_inode_scan(fs, ctx->inode_buffer_blocks,
                                              &scan);
        if (pctx.errcode) {
                fix_problem(ctx, PR_1B_ISCAN_ERROR, &pctx);
                ctx->flags |= E2F_FLAG_ABORT;
                return;
        }
        ctx->stashed_inode = EXT2_INODE(&inode);
        pb.ctx = ctx;
        pb.pctx = &pctx;
        pctx.str = "pass1b";
        while (1) {
                if (ino % (fs->super->s_inodes_per_group * 4) == 1) {
                        if (e2fsck_mmp_update(fs))
                                fatal_error(ctx, 0);
                }
                pctx.errcode = ext2fs_get_next_inode_full(scan, &ino,
                                EXT2_INODE(&inode), sizeof(inode));
                if (pctx.errcode == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE)
                        continue;
                if (pctx.errcode) {
                        pctx.ino = ino;
                        fix_problem(ctx, PR_1B_ISCAN_ERROR, &pctx);
                        ctx->flags |= E2F_FLAG_ABORT;
                        return;
                }
                if (!ino)
                        break;
                pctx.ino = ctx->stashed_ino = ino;
                if ((ino != EXT2_BAD_INO) &&
                    !ext2fs_test_inode_bitmap2(ctx->inode_used_map, ino))
                        continue;

                pb.ino = ino;
                pb.dup_blocks = 0;
                pb.inode = &inode;
                pb.cur_cluster = ~0;
                pb.phys_cluster = ~0;
                pb.last_blk = 0;
                pb.pctx->blk = pb.pctx->blk2 = 0;

                if (ext2fs_inode_has_valid_blocks2(fs, EXT2_INODE(&inode)) ||
                    (ino == EXT2_BAD_INO))
                        pctx.errcode = ext2fs_block_iterate3(fs, ino,
                                             BLOCK_FLAG_READ_ONLY, block_buf,
                                             process_pass1b_block, &pb);
                /* If the feature is not set, attrs will be cleared later anyway */
                if (ext2fs_has_feature_xattr(fs->super) &&
                    ext2fs_file_acl_block(fs, EXT2_INODE(&inode))) {
                        blk64_t blk = ext2fs_file_acl_block(fs, EXT2_INODE(&inode));
                        process_pass1b_block(fs, &blk,
                                             BLOCK_COUNT_EXTATTR, 0, 0, &pb);
                        ext2fs_file_acl_block_set(fs, EXT2_INODE(&inode), blk);
                }
                if (pb.dup_blocks) {
                        if (ino != EXT2_BAD_INO) {
                                op = pctx.blk == pctx.blk2 ?
                                        PR_1B_DUP_BLOCK : PR_1B_DUP_RANGE;
                                fix_problem(ctx, op, pb.pctx);
                        }
                        end_problem_latch(ctx, PR_LATCH_DBLOCK);
                        if (ino >= EXT2_FIRST_INODE(fs->super) ||
                            ino == EXT2_ROOT_INO)
                                dup_inode_count++;
                }
                if (pctx.errcode)
                        fix_problem(ctx, PR_1B_BLOCK_ITERATE, &pctx);
        }
        ext2fs_close_inode_scan(scan);
        e2fsck_use_inode_shortcuts(ctx, 0);
}

static int process_pass1b_block(ext2_filsys fs EXT2FS_ATTR((unused)),
                                blk64_t *block_nr,
                                e2_blkcnt_t blockcnt,
                                blk64_t ref_blk EXT2FS_ATTR((unused)),
                                int ref_offset EXT2FS_ATTR((unused)),
                                void *priv_data)
{
        struct process_block_struct *p;
        e2fsck_t ctx;
        blk64_t lc, pc;
        problem_t op;

        if (*block_nr == 0)
                return 0;
        p = (struct process_block_struct *) priv_data;
        ctx = p->ctx;
        lc = EXT2FS_B2C(fs, blockcnt);
        pc = EXT2FS_B2C(fs, *block_nr);

        if (!ext2fs_test_block_bitmap2(ctx->block_dup_map, *block_nr))
                goto finish;

        /* OK, this is a duplicate block */
        if (p->ino != EXT2_BAD_INO) {
                if (p->last_blk + 1 != *block_nr) {
                        if (p->last_blk) {
                                op = p->pctx->blk == p->pctx->blk2 ?
                                                PR_1B_DUP_BLOCK :
                                                PR_1B_DUP_RANGE;
                                fix_problem(ctx, op, p->pctx);
                        }
                        p->pctx->blk = *block_nr;
                }
                p->pctx->blk2 = *block_nr;
                p->last_blk = *block_nr;
        }
        p->dup_blocks++;
        ext2fs_mark_inode_bitmap2(inode_dup_map, p->ino);

        /*
         * Qualifications for submitting a block for duplicate processing:
         * It's an extent/indirect block (and has a negative logical offset);
         * we've crossed a logical cluster boundary; or the physical cluster
         * suddenly changed, which indicates that blocks in a logical cluster
         * are mapped to multiple physical clusters.
         */
        if (blockcnt < 0 || lc != p->cur_cluster || pc != p->phys_cluster)
                add_dupe(ctx, p->ino, EXT2FS_B2C(fs, *block_nr), p->inode);

finish:
        p->cur_cluster = lc;
        p->phys_cluster = pc;
        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;
        ext2_ino_t      first_inode;
        ext2_ino_t      max_inode;
};

static int search_dirent_proc(ext2_ino_t dir, int entry,
                              struct ext2_dir_entry *dirent,
                              int offset EXT2FS_ATTR((unused)),
                              int blocksize EXT2FS_ATTR((unused)),
                              char *buf EXT2FS_ATTR((unused)),
                              void *priv_data)
{
        struct search_dir_struct *sd;
        struct dup_inode        *p;
        dnode_t                 *n;

        sd = (struct search_dir_struct *) priv_data;

        if (dirent->inode > sd->max_inode)
                /* Should abort this inode, but not everything */
                return 0;

        if ((dirent->inode < sd->first_inode) || (entry < DIRENT_OTHER_FILE) ||
            !ext2fs_test_inode_bitmap2(inode_dup_map, dirent->inode))
                return 0;

        n = dict_lookup(&ino_dict, INT_TO_VOIDPTR(dirent->inode));
        if (!n)
                return 0;
        p = (struct dup_inode *) dnode_get(n);
        if (!p->dir) {
                p->dir = dir;
                sd->count--;
        }

        return(sd->count ? 0 : DIRENT_ABORT);
}


static void pass1c(e2fsck_t ctx, char *block_buf)
{
        ext2_filsys fs = ctx->fs;
        struct search_dir_struct sd;
        struct problem_context pctx;

        clear_problem_context(&pctx);

        if (!(ctx->options & E2F_OPT_PREEN))
                fix_problem(ctx, PR_1C_PASS_HEADER, &pctx);

        /*
         * Search through all directories to translate inodes to names
         * (by searching for the containing directory for that inode.)
         */
        sd.count = dup_inode_count - dup_inode_founddir;
        sd.first_inode = EXT2_FIRST_INODE(fs->super);
        sd.max_inode = fs->super->s_inodes_count;
        ext2fs_dblist_dir_iterate(fs->dblist, 0, block_buf,
                                  search_dirent_proc, &sd);
}

static void pass1d(e2fsck_t ctx, char *block_buf)
{
        ext2_filsys fs = ctx->fs;
        struct dup_inode        *p, *t;
        struct dup_cluster      *q;
        ext2_ino_t              *shared, ino;
        int     shared_len;
        int     i;
        int     file_ok;
        int     meta_data = 0;
        struct problem_context pctx;
        dnode_t *n, *m;
        struct cluster_el       *s;
        struct inode_el *r;

        clear_problem_context(&pctx);

        if (!(ctx->options & E2F_OPT_PREEN))
                fix_problem(ctx, PR_1D_PASS_HEADER, &pctx);
        e2fsck_read_bitmaps(ctx);

        pctx.num = dup_inode_count; /* dict_count(&ino_dict); */
        fix_problem(ctx, PR_1D_NUM_DUP_INODES, &pctx);
        shared = (ext2_ino_t *) e2fsck_allocate_memory(ctx,
                                sizeof(ext2_ino_t) * dict_count(&ino_dict),
                                "Shared inode list");
        for (n = dict_first(&ino_dict); n; n = dict_next(&ino_dict, n)) {
                p = (struct dup_inode *) dnode_get(n);
                shared_len = 0;
                file_ok = 1;
                ino = (ext2_ino_t)VOIDPTR_TO_INT(dnode_getkey(n));
                if (ino == EXT2_BAD_INO || ino == EXT2_RESIZE_INO)
                        continue;

                /*
                 * Find all of the inodes which share blocks with this
                 * one.  First we find all of the duplicate blocks
                 * belonging to this inode, and then search each block
                 * get the list of inodes, and merge them together.
                 */
                for (s = p->cluster_list; s; s = s->next) {
                        m = dict_lookup(&clstr_dict,
                                        INT_TO_VOIDPTR(s->cluster));
                        if (!m)
                                continue; /* Should never happen... */
                        q = (struct dup_cluster *) dnode_get(m);
                        if (q->num_bad > 1)
                                file_ok = 0;
                        if (check_if_fs_cluster(ctx, s->cluster)) {
                                file_ok = 0;
                                meta_data = 1;
                        }

                        /*
                         * 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->inode_list; r; r = r->next) {
                                if (r->inode == ino)
                                        continue;
                                for (i = 0; i < shared_len; i++)
                                        if (shared[i] == r->inode)
                                                break;
                                if (i == shared_len) {
                                        shared[shared_len++] = r->inode;
                                }
                        }
                }

                /*
                 * Report the inode that we are working on
                 */
                pctx.inode = EXT2_INODE(&p->inode);
                pctx.ino = ino;
                pctx.dir = p->dir;
                pctx.blkcount = p->num_dupblocks;
                pctx.num = meta_data ? shared_len+1 : shared_len;
                fix_problem(ctx, PR_1D_DUP_FILE, &pctx);
                pctx.blkcount = 0;
                pctx.num = 0;

                if (meta_data)
                        fix_problem(ctx, PR_1D_SHARE_METADATA, &pctx);

                for (i = 0; i < shared_len; i++) {
                        m = dict_lookup(&ino_dict, INT_TO_VOIDPTR(shared[i]));
                        if (!m)
                                continue; /* should never happen */
                        t = (struct dup_inode *) dnode_get(m);
                        /*
                         * Report the inode that we are sharing with
                         */
                        pctx.inode = EXT2_INODE(&t->inode);
                        pctx.ino = shared[i];
                        pctx.dir = t->dir;
                        fix_problem(ctx, PR_1D_DUP_FILE_LIST, &pctx);
                }
                /*
                 * Even if the file shares blocks with itself, we still need to
                 * clone the blocks.
                 */
                if (file_ok && (meta_data ? shared_len+1 : shared_len) != 0) {
                        fix_problem(ctx, PR_1D_DUP_BLOCKS_DEALT, &pctx);
                        continue;
                }
                if (fix_problem(ctx, PR_1D_CLONE_QUESTION, &pctx)) {
                        pctx.errcode = clone_file(ctx, ino, p, block_buf);
                        if (pctx.errcode)
                                fix_problem(ctx, PR_1D_CLONE_ERROR, &pctx);
                        else
                                continue;
                }
                if (fix_problem(ctx, PR_1D_DELETE_QUESTION, &pctx))
                        delete_file(ctx, ino, p, block_buf);
                else
                        ext2fs_unmark_valid(fs);
        }
        ext2fs_free_mem(&shared);
}

/*
 * Drop the refcount on the dup_block structure, and clear the entry
 * in the block_dup_map if appropriate.
 */
static void decrement_badcount(e2fsck_t ctx, blk64_t block,
                               struct dup_cluster *p)
{
        p->num_bad--;
        if (p->num_bad <= 0 ||
            (p->num_bad == 1 && !check_if_fs_block(ctx, block))) {
                if (check_if_fs_cluster(ctx, EXT2FS_B2C(ctx->fs, block)))
                        return;
                ext2fs_unmark_block_bitmap2(ctx->block_dup_map, block);
        }
}

static int delete_file_block(ext2_filsys fs,
                             blk64_t    *block_nr,
                             e2_blkcnt_t blockcnt,
                             blk64_t ref_block EXT2FS_ATTR((unused)),
                             int ref_offset EXT2FS_ATTR((unused)),
                             void *priv_data)
{
        struct process_block_struct *pb;
        struct dup_cluster *p;
        dnode_t *n;
        e2fsck_t ctx;
        blk64_t c, lc;

        pb = (struct process_block_struct *) priv_data;
        ctx = pb->ctx;

        if (*block_nr == 0)
                return 0;

        c = EXT2FS_B2C(fs, *block_nr);
        lc = EXT2FS_B2C(fs, blockcnt);
        if (ext2fs_test_block_bitmap2(ctx->block_dup_map, *block_nr)) {
                n = dict_lookup(&clstr_dict, INT_TO_VOIDPTR(c));
                if (n) {
                        if (lc != pb->cur_cluster) {
                                p = (struct dup_cluster *) dnode_get(n);
                                decrement_badcount(ctx, *block_nr, p);
                                pb->dup_blocks++;
                        }
                } else
                        com_err("delete_file_block", 0,
                            _("internal error: can't find dup_blk for %llu\n"),
                                *block_nr);
        } else {
                if ((*block_nr % EXT2FS_CLUSTER_RATIO(ctx->fs)) == 0)
                        ext2fs_block_alloc_stats2(fs, *block_nr, -1);
                pb->dup_blocks++;
        }
        pb->cur_cluster = lc;

        return 0;
}

static void delete_file(e2fsck_t ctx, ext2_ino_t ino,
                        struct dup_inode *dp, char* block_buf)
{
        ext2_filsys fs = ctx->fs;
        struct process_block_struct pb;
        struct problem_context  pctx;
        unsigned int            count;

        clear_problem_context(&pctx);
        pctx.ino = pb.ino = ino;
        pb.dup_blocks = 0;
        pb.ctx = ctx;
        pctx.str = "delete_file";
        pb.cur_cluster = ~0;

        if (ext2fs_inode_has_valid_blocks2(fs, EXT2_INODE(&dp->inode)))
                pctx.errcode = ext2fs_block_iterate3(fs, ino,
                                                     BLOCK_FLAG_READ_ONLY,
                                                     block_buf,
                                                     delete_file_block, &pb);
        if (pctx.errcode)
                fix_problem(ctx, PR_1B_BLOCK_ITERATE, &pctx);
        if (ctx->inode_bad_map)
                ext2fs_unmark_inode_bitmap2(ctx->inode_bad_map, ino);
        ext2fs_inode_alloc_stats2(fs, ino, -1, LINUX_S_ISDIR(dp->inode.i_mode));
        quota_data_sub(ctx->qctx, &dp->inode, ino,
                       pb.dup_blocks * fs->blocksize);
        quota_data_inodes(ctx->qctx, &dp->inode, ino, -1);

        /* Inode may have changed by block_iterate, so reread it */
        e2fsck_read_inode_full(ctx, ino, EXT2_INODE(&dp->inode),
                               sizeof(dp->inode), "delete_file");
        e2fsck_clear_inode(ctx, ino, EXT2_INODE(&dp->inode), 0, "delete_file");
        if (ext2fs_file_acl_block(fs, EXT2_INODE(&dp->inode)) &&
            ext2fs_has_feature_xattr(fs->super)) {
                blk64_t file_acl_block = ext2fs_file_acl_block(fs,
                                                EXT2_INODE(&dp->inode));

                count = 1;
                pctx.errcode = ext2fs_adjust_ea_refcount3(fs, file_acl_block,
                                        block_buf, -1, &count, ino);
                if (pctx.errcode == EXT2_ET_BAD_EA_BLOCK_NUM) {
                        pctx.errcode = 0;
                        count = 1;
                }
                if (pctx.errcode) {
                        pctx.blk = file_acl_block;
                        fix_problem(ctx, PR_1B_ADJ_EA_REFCOUNT, &pctx);
                }
                /*
                 * If the count is zero, then arrange to have the
                 * block deleted.  If the block is in the block_dup_map,
                 * also call delete_file_block since it will take care
                 * of keeping the accounting straight.
                 */
                if ((count == 0) ||
                    ext2fs_test_block_bitmap2(ctx->block_dup_map,
                                              file_acl_block)) {
                        delete_file_block(fs, &file_acl_block,
                                          BLOCK_COUNT_EXTATTR, 0, 0, &pb);
                        ext2fs_file_acl_block_set(fs, EXT2_INODE(&dp->inode),
                                                  file_acl_block);
                        quota_data_sub(ctx->qctx, &dp->inode, ino,
                                       fs->blocksize);
                }
        }
}

struct clone_struct {
        errcode_t       errcode;
        blk64_t         dup_cluster;
        blk64_t         alloc_block;
        ext2_ino_t      dir, ino;
        char    *buf;
        e2fsck_t ctx;
        struct ext2_inode_large *inode;

        struct dup_cluster *save_dup_cluster;
        blk64_t save_blocknr;
};

/*
 * Decrement the bad count *after* we've shown that (a) we can allocate a
 * replacement block and (b) remap the file blocks.  Unfortunately, there's no
 * way to find out if the remap succeeded until either the next
 * clone_file_block() call (an error when remapping the block after returning
 * BLOCK_CHANGED will halt the iteration) or after block_iterate() returns.
 * Otherwise, it's possible that we decrease the badcount once in preparation
 * to remap, then the remap fails (either we can't find a replacement block or
 * we have to split the extent tree and can't find a new extent block), so we
 * delete the file, which decreases the badcount again.
 */
static void deferred_dec_badcount(struct clone_struct *cs)
{
        if (!cs->save_dup_cluster)
                return;
        decrement_badcount(cs->ctx, cs->save_blocknr, cs->save_dup_cluster);
        cs->save_dup_cluster = NULL;
}

static int clone_file_block(ext2_filsys fs,
                            blk64_t     *block_nr,
                            e2_blkcnt_t blockcnt,
                            blk64_t ref_block EXT2FS_ATTR((unused)),
                            int ref_offset EXT2FS_ATTR((unused)),
                            void *priv_data)
{
        struct dup_cluster *p = NULL;
        blk64_t new_block;
        errcode_t       retval;
        struct clone_struct *cs = (struct clone_struct *) priv_data;
        dnode_t *n;
        e2fsck_t ctx;
        blk64_t c;
        int is_meta = 0;

        ctx = cs->ctx;
        deferred_dec_badcount(cs);

        if (*block_nr == 0)
                return 0;

        c = EXT2FS_B2C(fs, blockcnt);
        if (check_if_fs_cluster(ctx, EXT2FS_B2C(fs, *block_nr)))
                is_meta = 1;

        if (c == cs->dup_cluster && cs->alloc_block) {
                new_block = cs->alloc_block;
                goto got_block;
        }

        if (ext2fs_test_block_bitmap2(ctx->block_dup_map, *block_nr)) {
                n = dict_lookup(&clstr_dict,
                                INT_TO_VOIDPTR(EXT2FS_B2C(fs, *block_nr)));
                if (!n) {
                        com_err("clone_file_block", 0,
                            _("internal error: can't find dup_blk for %llu\n"),
                                *block_nr);
                        return 0;
                }

                p = (struct dup_cluster *) dnode_get(n);

                cs->dup_cluster = c;
                /*
                 * Let's try an implied cluster allocation.  If we get the same
                 * cluster back, then we need to find a new block; otherwise,
                 * we're merely fixing the problem of one logical cluster being
                 * mapped to multiple physical clusters.
                 */
                new_block = 0;
                retval = ext2fs_map_cluster_block(fs, cs->ino,
                                                  EXT2_INODE(cs->inode),
                                                  blockcnt, &new_block);
                if (retval == 0 && new_block != 0 &&
                    EXT2FS_B2C(ctx->fs, new_block) !=
                    EXT2FS_B2C(ctx->fs, *block_nr))
                        goto cluster_alloc_ok;
                retval = ext2fs_new_block2(fs, 0, ctx->block_found_map,
                                           &new_block);
                if (retval) {
                        cs->errcode = retval;
                        return BLOCK_ABORT;
                }
cluster_alloc_ok:
                cs->alloc_block = new_block;

        got_block:
                new_block &= ~EXT2FS_CLUSTER_MASK(fs);
                new_block += EXT2FS_CLUSTER_MASK(fs) & blockcnt;
                if (cs->dir && (blockcnt >= 0)) {
                        retval = ext2fs_set_dir_block2(fs->dblist,
                                        cs->dir, new_block, blockcnt);
                        if (retval) {
                                cs->errcode = retval;
                                return BLOCK_ABORT;
                        }
                }
#if 0
                printf("Cloning block #%lld from %llu to %llu\n",
                       blockcnt, *block_nr, new_block);
#endif
                retval = io_channel_read_blk64(fs->io, *block_nr, 1, cs->buf);
                if (retval) {
                        cs->errcode = retval;
                        return BLOCK_ABORT;
                }
                retval = io_channel_write_blk64(fs->io, new_block, 1, cs->buf);
                if (retval) {
                        cs->errcode = retval;
                        return BLOCK_ABORT;
                }
                cs->save_dup_cluster = (is_meta ? NULL : p);
                cs->save_blocknr = *block_nr;
                *block_nr = new_block;
                ext2fs_mark_block_bitmap2(ctx->block_found_map, new_block);
                ext2fs_mark_block_bitmap2(fs->block_map, new_block);
                return BLOCK_CHANGED;
        }
        return 0;
}

static errcode_t clone_file(e2fsck_t ctx, ext2_ino_t ino,
                            struct dup_inode *dp, char* block_buf)
{
        ext2_filsys fs = ctx->fs;
        errcode_t       retval;
        struct clone_struct cs;
        struct problem_context  pctx;
        blk64_t         blk, new_blk;
        dnode_t         *n;
        struct inode_el *ino_el;
        struct dup_cluster      *dc;
        struct dup_inode        *di;

        clear_problem_context(&pctx);
        cs.errcode = 0;
        cs.dir = 0;
        cs.dup_cluster = ~0;
        cs.alloc_block = 0;
        cs.ctx = ctx;
        cs.ino = ino;
        cs.inode = &dp->inode;
        cs.save_dup_cluster = NULL;
        cs.save_blocknr = 0;
        retval = ext2fs_get_mem(fs->blocksize, &cs.buf);
        if (retval)
                return retval;

        if (ext2fs_test_inode_bitmap2(ctx->inode_dir_map, ino))
                cs.dir = ino;

        pctx.ino = ino;
        pctx.str = "clone_file";
        if (ext2fs_inode_has_valid_blocks2(fs, EXT2_INODE(&dp->inode)))
                pctx.errcode = ext2fs_block_iterate3(fs, ino, 0, block_buf,
                                                     clone_file_block, &cs);
        deferred_dec_badcount(&cs);
        ext2fs_mark_bb_dirty(fs);
        if (pctx.errcode) {
                fix_problem(ctx, PR_1B_BLOCK_ITERATE, &pctx);
                retval = pctx.errcode;
                goto errout;
        }
        if (cs.errcode) {
                com_err("clone_file", cs.errcode, "%s",
                        _("returned from clone_file_block"));
                retval = cs.errcode;
                goto errout;
        }
        /* The inode may have changed on disk, so we have to re-read it */
        e2fsck_read_inode_full(ctx, ino, EXT2_INODE(&dp->inode),
                               sizeof(dp->inode), "clone file EA");
        blk = ext2fs_file_acl_block(fs, EXT2_INODE(&dp->inode));
        new_blk = blk;
        if (blk && (clone_file_block(fs, &new_blk,
                                     BLOCK_COUNT_EXTATTR, 0, 0, &cs) ==
                    BLOCK_CHANGED)) {
                ext2fs_file_acl_block_set(fs, EXT2_INODE(&dp->inode), new_blk);
                e2fsck_write_inode_full(ctx, ino, EXT2_INODE(&dp->inode),
                                        sizeof(dp->inode), "clone file EA");
                /*
                 * If we cloned the EA block, find all other inodes
                 * which referred to that EA block, and modify
                 * them to point to the new EA block.
                 */
                n = dict_lookup(&clstr_dict,
                                INT_TO_VOIDPTR(EXT2FS_B2C(fs, blk)));
                if (!n) {
                        com_err("clone_file", 0,
                                _("internal error: couldn't lookup EA "
                                  "block record for %llu"), blk);
                        retval = 0; /* OK to stumble on... */
                        goto errout;
                }
                dc = (struct dup_cluster *) dnode_get(n);
                for (ino_el = dc->inode_list; ino_el; ino_el = ino_el->next) {
                        if (ino_el->inode == ino)
                                continue;
                        n = dict_lookup(&ino_dict, INT_TO_VOIDPTR(ino_el->inode));
                        if (!n) {
                                com_err("clone_file", 0,
                                        _("internal error: couldn't lookup EA "
                                          "inode record for %u"),
                                        ino_el->inode);
                                retval = 0; /* OK to stumble on... */
                                goto errout;
                        }
                        di = (struct dup_inode *) dnode_get(n);
                        if (ext2fs_file_acl_block(fs,
                                        EXT2_INODE(&di->inode)) == blk) {
                                ext2fs_file_acl_block_set(fs,
                                        EXT2_INODE(&di->inode),
                                        ext2fs_file_acl_block(fs, EXT2_INODE(&dp->inode)));
                                e2fsck_write_inode_full(ctx, ino_el->inode,
                                        EXT2_INODE(&di->inode),
                                        sizeof(di->inode), "clone file EA");
                                decrement_badcount(ctx, blk, dc);
                        }
                }
        }
        retval = 0;
errout:
        ext2fs_free_mem(&cs.buf);
        return retval;
}

/*
 * This routine returns 1 if a block overlaps with one of the superblocks,
 * group descriptors, inode bitmaps, or block bitmaps.
 */
static int check_if_fs_block(e2fsck_t ctx, blk64_t test_block)
{
        ext2_filsys fs = ctx->fs;
        blk64_t first_block;
        dgrp_t  i;

        first_block = fs->super->s_first_data_block;
        for (i = 0; i < fs->group_desc_count; i++) {

                /* Check superblocks/block group descriptors */
                if (ext2fs_bg_has_super(fs, i)) {
                        if (test_block >= first_block &&
                            (test_block <= first_block + fs->desc_blocks))
                                return 1;
                }

                /* Check the inode table */
                if ((ext2fs_inode_table_loc(fs, i)) &&
                    (test_block >= ext2fs_inode_table_loc(fs, i)) &&
                    (test_block < (ext2fs_inode_table_loc(fs, i) +
                                   fs->inode_blocks_per_group)))
                        return 1;

                /* Check the bitmap blocks */
                if ((test_block == ext2fs_block_bitmap_loc(fs, i)) ||
                    (test_block == ext2fs_inode_bitmap_loc(fs, i)))
                        return 1;

                first_block += fs->super->s_blocks_per_group;
        }
        return 0;
}

/*
 * This routine returns 1 if a cluster overlaps with one of the superblocks,
 * group descriptors, inode bitmaps, or block bitmaps.
 */
static int check_if_fs_cluster(e2fsck_t ctx, blk64_t cluster)
{
        ext2_filsys fs = ctx->fs;
        blk64_t first_block;
        dgrp_t  i;

        first_block = fs->super->s_first_data_block;
        for (i = 0; i < fs->group_desc_count; i++) {

                /* Check superblocks/block group descriptors */
                if (ext2fs_bg_has_super(fs, i)) {
                        if (cluster >= EXT2FS_B2C(fs, first_block) &&
                            (cluster <= EXT2FS_B2C(fs, first_block +
                                                   fs->desc_blocks)))
                                return 1;
                }

                /* Check the inode table */
                if ((ext2fs_inode_table_loc(fs, i)) &&
                    (cluster >= EXT2FS_B2C(fs,
                                           ext2fs_inode_table_loc(fs, i))) &&
                    (cluster <= EXT2FS_B2C(fs,
                                           ext2fs_inode_table_loc(fs, i) +
                                           fs->inode_blocks_per_group - 1)))
                        return 1;

                /* Check the bitmap blocks */
                if ((cluster == EXT2FS_B2C(fs,
                                           ext2fs_block_bitmap_loc(fs, i))) ||
                    (cluster == EXT2FS_B2C(fs,
                                           ext2fs_inode_bitmap_loc(fs, i))))
                        return 1;

                first_block += fs->super->s_blocks_per_group;
        }
        return 0;
}