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 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * This file is part of UBIFS.
  *
  * Copyright (C) 2006-2008 Nokia Corporation
  *
  * Authors: Artem Bityutskiy (Битюцкий Артём)
  *          Adrian Hunter
  */
 
 /*
  * This file implements most of the debugging stuff which is compiled in only
  * when it is enabled. But some debugging check functions are implemented in
  * corresponding subsystem, just because they are closely related and utilize
  * various local functions of those subsystems.
  */
 
 #include <linux/module.h>
 #include <linux/debugfs.h>
 #include <linux/math64.h>
 #include <linux/uaccess.h>
 #include <linux/random.h>
 #include <linux/ctype.h>
 #include "ubifs.h"
 
 static DEFINE_SPINLOCK(dbg_lock);
 
 static const char *get_key_fmt(int fmt)
 {
     switch (fmt) {
     case UBIFS_SIMPLE_KEY_FMT:
         return "simple";
     default:
         return "unknown/invalid format";
     }
 }
 
 static const char *get_key_hash(int hash)
 {
     switch (hash) {
     case UBIFS_KEY_HASH_R5:
         return "R5";
     case UBIFS_KEY_HASH_TEST:
         return "test";
     default:
         return "unknown/invalid name hash";
     }
 }
 
 static const char *get_key_type(int type)
 {
     switch (type) {
     case UBIFS_INO_KEY:
         return "inode";
     case UBIFS_DENT_KEY:
         return "direntry";
     case UBIFS_XENT_KEY:
         return "xentry";
     case UBIFS_DATA_KEY:
         return "data";
     case UBIFS_TRUN_KEY:
         return "truncate";
     default:
         return "unknown/invalid key";
     }
 }
 
 static const char *get_dent_type(int type)
 {
     switch (type) {
     case UBIFS_ITYPE_REG:
         return "file";
     case UBIFS_ITYPE_DIR:
         return "dir";
     case UBIFS_ITYPE_LNK:
         return "symlink";
     case UBIFS_ITYPE_BLK:
         return "blkdev";
     case UBIFS_ITYPE_CHR:
         return "char dev";
     case UBIFS_ITYPE_FIFO:
         return "fifo";
     case UBIFS_ITYPE_SOCK:
         return "socket";
     default:
         return "unknown/invalid type";
     }
 }
 
 const char *dbg_snprintf_key(const struct ubifs_info *c,
                  const union ubifs_key *key, char *buffer, int len)
 {
     char *p = buffer;
     int type = key_type(c, key);
 
     if (c->key_fmt == UBIFS_SIMPLE_KEY_FMT) {
         switch (type) {
         case UBIFS_INO_KEY:
             len -= snprintf(p, len, "(%lu, %s)",
                     (unsigned long)key_inum(c, key),
                     get_key_type(type));
             break;
         case UBIFS_DENT_KEY:
         case UBIFS_XENT_KEY:
             len -= snprintf(p, len, "(%lu, %s, %#08x)",
                     (unsigned long)key_inum(c, key),
                     get_key_type(type), key_hash(c, key));
             break;
         case UBIFS_DATA_KEY:
             len -= snprintf(p, len, "(%lu, %s, %u)",
                     (unsigned long)key_inum(c, key),
                     get_key_type(type), key_block(c, key));
             break;
         case UBIFS_TRUN_KEY:
             len -= snprintf(p, len, "(%lu, %s)",
                     (unsigned long)key_inum(c, key),
                     get_key_type(type));
             break;
         default:
             len -= snprintf(p, len, "(bad key type: %#08x, %#08x)",
                     key->u32[0], key->u32[1]);
         }
     } else
         len -= snprintf(p, len, "bad key format %d", c->key_fmt);
     ubifs_assert(c, len > 0);
     return p;
 }
 
 const char *dbg_ntype(int type)
 {
     switch (type) {
     case UBIFS_PAD_NODE:
         return "padding node";
     case UBIFS_SB_NODE:
         return "superblock node";
     case UBIFS_MST_NODE:
         return "master node";
     case UBIFS_REF_NODE:
         return "reference node";
     case UBIFS_INO_NODE:
         return "inode node";
     case UBIFS_DENT_NODE:
         return "direntry node";
     case UBIFS_XENT_NODE:
         return "xentry node";
     case UBIFS_DATA_NODE:
         return "data node";
     case UBIFS_TRUN_NODE:
         return "truncate node";
     case UBIFS_IDX_NODE:
         return "indexing node";
     case UBIFS_CS_NODE:
         return "commit start node";
     case UBIFS_ORPH_NODE:
         return "orphan node";
     case UBIFS_AUTH_NODE:
         return "auth node";
     default:
         return "unknown node";
     }
 }
 
 static const char *dbg_gtype(int type)
 {
     switch (type) {
     case UBIFS_NO_NODE_GROUP:
         return "no node group";
     case UBIFS_IN_NODE_GROUP:
         return "in node group";
     case UBIFS_LAST_OF_NODE_GROUP:
         return "last of node group";
     default:
         return "unknown";
     }
 }
 
 const char *dbg_cstate(int cmt_state)
 {
     switch (cmt_state) {
     case COMMIT_RESTING:
         return "commit resting";
     case COMMIT_BACKGROUND:
         return "background commit requested";
     case COMMIT_REQUIRED:
         return "commit required";
     case COMMIT_RUNNING_BACKGROUND:
         return "BACKGROUND commit running";
     case COMMIT_RUNNING_REQUIRED:
         return "commit running and required";
     case COMMIT_BROKEN:
         return "broken commit";
     default:
         return "unknown commit state";
     }
 }
 
 const char *dbg_jhead(int jhead)
 {
     switch (jhead) {
     case GCHD:
         return "0 (GC)";
     case BASEHD:
         return "1 (base)";
     case DATAHD:
         return "2 (data)";
     default:
         return "unknown journal head";
     }
 }
 
 static void dump_ch(const struct ubifs_ch *ch)
 {
     pr_err("\tmagic          %#x\n", le32_to_cpu(ch->magic));
     pr_err("\tcrc            %#x\n", le32_to_cpu(ch->crc));
     pr_err("\tnode_type      %d (%s)\n", ch->node_type,
            dbg_ntype(ch->node_type));
     pr_err("\tgroup_type     %d (%s)\n", ch->group_type,
            dbg_gtype(ch->group_type));
     pr_err("\tsqnum          %llu\n",
            (unsigned long long)le64_to_cpu(ch->sqnum));
     pr_err("\tlen            %u\n", le32_to_cpu(ch->len));
 }
 
 void ubifs_dump_inode(struct ubifs_info *c, const struct inode *inode)
 {
     const struct ubifs_inode *ui = ubifs_inode(inode);
     struct fscrypt_name nm = {0};
     union ubifs_key key;
     struct ubifs_dent_node *dent, *pdent = NULL;
     int count = 2;
 
     pr_err("Dump in-memory inode:");
     pr_err("\tinode          %lu\n", inode->i_ino);
     pr_err("\tsize           %llu\n",
            (unsigned long long)i_size_read(inode));
     pr_err("\tnlink          %u\n", inode->i_nlink);
     pr_err("\tuid            %u\n", (unsigned int)i_uid_read(inode));
     pr_err("\tgid            %u\n", (unsigned int)i_gid_read(inode));
     pr_err("\tatime          %u.%u\n",
            (unsigned int)inode->i_atime.tv_sec,
            (unsigned int)inode->i_atime.tv_nsec);
     pr_err("\tmtime          %u.%u\n",
            (unsigned int)inode->i_mtime.tv_sec,
            (unsigned int)inode->i_mtime.tv_nsec);
     pr_err("\tctime          %u.%u\n",
            (unsigned int)inode->i_ctime.tv_sec,
            (unsigned int)inode->i_ctime.tv_nsec);
     pr_err("\tcreat_sqnum    %llu\n", ui->creat_sqnum);
     pr_err("\txattr_size     %u\n", ui->xattr_size);
     pr_err("\txattr_cnt      %u\n", ui->xattr_cnt);
     pr_err("\txattr_names    %u\n", ui->xattr_names);
     pr_err("\tdirty          %u\n", ui->dirty);
     pr_err("\txattr          %u\n", ui->xattr);
     pr_err("\tbulk_read      %u\n", ui->bulk_read);
     pr_err("\tsynced_i_size  %llu\n",
            (unsigned long long)ui->synced_i_size);
     pr_err("\tui_size        %llu\n",
            (unsigned long long)ui->ui_size);
     pr_err("\tflags          %d\n", ui->flags);
     pr_err("\tcompr_type     %d\n", ui->compr_type);
     pr_err("\tlast_page_read %lu\n", ui->last_page_read);
     pr_err("\tread_in_a_row  %lu\n", ui->read_in_a_row);
     pr_err("\tdata_len       %d\n", ui->data_len);
 
     if (!S_ISDIR(inode->i_mode))
         return;
 
     pr_err("List of directory entries:\n");
     ubifs_assert(c, !mutex_is_locked(&c->tnc_mutex));
 
     lowest_dent_key(c, &key, inode->i_ino);
     while (1) {
         dent = ubifs_tnc_next_ent(c, &key, &nm);
         if (IS_ERR(dent)) {
             if (PTR_ERR(dent) != -ENOENT)
                 pr_err("error %ld\n", PTR_ERR(dent));
             break;
         }
 
         pr_err("\t%d: inode %llu, type %s, len %d\n",
                count++, (unsigned long long) le64_to_cpu(dent->inum),
                get_dent_type(dent->type),
                le16_to_cpu(dent->nlen));
 
         fname_name(&nm) = dent->name;
         fname_len(&nm) = le16_to_cpu(dent->nlen);
         kfree(pdent);
         pdent = dent;
         key_read(c, &dent->key, &key);
     }
     kfree(pdent);
 }
 
 void ubifs_dump_node(const struct ubifs_info *c, const void *node, int node_len)
 {
     int i, n, type, safe_len, max_node_len, min_node_len;
     union ubifs_key key;
     const struct ubifs_ch *ch = node;
     char key_buf[DBG_KEY_BUF_LEN];
 
     /* If the magic is incorrect, just hexdump the first bytes */
     if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) {
         pr_err("Not a node, first %zu bytes:", UBIFS_CH_SZ);
         print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 32, 1,
                    (void *)node, UBIFS_CH_SZ, 1);
         return;
     }
 
     /* Skip dumping unknown type node */
     type = ch->node_type;
     if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) {
         pr_err("node type %d was not recognized\n", type);
         return;
     }
 
     spin_lock(&dbg_lock);
     dump_ch(node);
 
     if (c->ranges[type].max_len == 0) {
         max_node_len = min_node_len = c->ranges[type].len;
     } else {
         max_node_len = c->ranges[type].max_len;
         min_node_len = c->ranges[type].min_len;
     }
     safe_len = le32_to_cpu(ch->len);
     safe_len = safe_len > 0 ? safe_len : 0;
     safe_len = min3(safe_len, max_node_len, node_len);
     if (safe_len < min_node_len) {
         pr_err("node len(%d) is too short for %s, left %d bytes:\n",
                safe_len, dbg_ntype(type),
                safe_len > UBIFS_CH_SZ ?
                safe_len - (int)UBIFS_CH_SZ : 0);
         if (safe_len > UBIFS_CH_SZ)
             print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 32, 1,
                        (void *)node + UBIFS_CH_SZ,
                        safe_len - UBIFS_CH_SZ, 0);
         goto out_unlock;
     }
     if (safe_len != le32_to_cpu(ch->len))
         pr_err("\ttruncated node length      %d\n", safe_len);
 
     switch (type) {
     case UBIFS_PAD_NODE:
     {
         const struct ubifs_pad_node *pad = node;
 
         pr_err("\tpad_len        %u\n", le32_to_cpu(pad->pad_len));
         break;
     }
     case UBIFS_SB_NODE:
     {
         const struct ubifs_sb_node *sup = node;
         unsigned int sup_flags = le32_to_cpu(sup->flags);
 
         pr_err("\tkey_hash       %d (%s)\n",
                (int)sup->key_hash, get_key_hash(sup->key_hash));
         pr_err("\tkey_fmt        %d (%s)\n",
                (int)sup->key_fmt, get_key_fmt(sup->key_fmt));
         pr_err("\tflags          %#x\n", sup_flags);
         pr_err("\tbig_lpt        %u\n",
                !!(sup_flags & UBIFS_FLG_BIGLPT));
         pr_err("\tspace_fixup    %u\n",
                !!(sup_flags & UBIFS_FLG_SPACE_FIXUP));
         pr_err("\tmin_io_size    %u\n", le32_to_cpu(sup->min_io_size));
         pr_err("\tleb_size       %u\n", le32_to_cpu(sup->leb_size));
         pr_err("\tleb_cnt        %u\n", le32_to_cpu(sup->leb_cnt));
         pr_err("\tmax_leb_cnt    %u\n", le32_to_cpu(sup->max_leb_cnt));
         pr_err("\tmax_bud_bytes  %llu\n",
                (unsigned long long)le64_to_cpu(sup->max_bud_bytes));
         pr_err("\tlog_lebs       %u\n", le32_to_cpu(sup->log_lebs));
         pr_err("\tlpt_lebs       %u\n", le32_to_cpu(sup->lpt_lebs));
         pr_err("\torph_lebs      %u\n", le32_to_cpu(sup->orph_lebs));
         pr_err("\tjhead_cnt      %u\n", le32_to_cpu(sup->jhead_cnt));
         pr_err("\tfanout         %u\n", le32_to_cpu(sup->fanout));
         pr_err("\tlsave_cnt      %u\n", le32_to_cpu(sup->lsave_cnt));
         pr_err("\tdefault_compr  %u\n",
                (int)le16_to_cpu(sup->default_compr));
         pr_err("\trp_size        %llu\n",
                (unsigned long long)le64_to_cpu(sup->rp_size));
         pr_err("\trp_uid         %u\n", le32_to_cpu(sup->rp_uid));
         pr_err("\trp_gid         %u\n", le32_to_cpu(sup->rp_gid));
         pr_err("\tfmt_version    %u\n", le32_to_cpu(sup->fmt_version));
         pr_err("\ttime_gran      %u\n", le32_to_cpu(sup->time_gran));
         pr_err("\tUUID           %pUB\n", sup->uuid);
         break;
     }
     case UBIFS_MST_NODE:
     {
         const struct ubifs_mst_node *mst = node;
 
         pr_err("\thighest_inum   %llu\n",
                (unsigned long long)le64_to_cpu(mst->highest_inum));
         pr_err("\tcommit number  %llu\n",
                (unsigned long long)le64_to_cpu(mst->cmt_no));
         pr_err("\tflags          %#x\n", le32_to_cpu(mst->flags));
         pr_err("\tlog_lnum       %u\n", le32_to_cpu(mst->log_lnum));
         pr_err("\troot_lnum      %u\n", le32_to_cpu(mst->root_lnum));
         pr_err("\troot_offs      %u\n", le32_to_cpu(mst->root_offs));
         pr_err("\troot_len       %u\n", le32_to_cpu(mst->root_len));
         pr_err("\tgc_lnum        %u\n", le32_to_cpu(mst->gc_lnum));
         pr_err("\tihead_lnum     %u\n", le32_to_cpu(mst->ihead_lnum));
         pr_err("\tihead_offs     %u\n", le32_to_cpu(mst->ihead_offs));
         pr_err("\tindex_size     %llu\n",
                (unsigned long long)le64_to_cpu(mst->index_size));
         pr_err("\tlpt_lnum       %u\n", le32_to_cpu(mst->lpt_lnum));
         pr_err("\tlpt_offs       %u\n", le32_to_cpu(mst->lpt_offs));
         pr_err("\tnhead_lnum     %u\n", le32_to_cpu(mst->nhead_lnum));
         pr_err("\tnhead_offs     %u\n", le32_to_cpu(mst->nhead_offs));
         pr_err("\tltab_lnum      %u\n", le32_to_cpu(mst->ltab_lnum));
         pr_err("\tltab_offs      %u\n", le32_to_cpu(mst->ltab_offs));
         pr_err("\tlsave_lnum     %u\n", le32_to_cpu(mst->lsave_lnum));
         pr_err("\tlsave_offs     %u\n", le32_to_cpu(mst->lsave_offs));
         pr_err("\tlscan_lnum     %u\n", le32_to_cpu(mst->lscan_lnum));
         pr_err("\tleb_cnt        %u\n", le32_to_cpu(mst->leb_cnt));
         pr_err("\tempty_lebs     %u\n", le32_to_cpu(mst->empty_lebs));
         pr_err("\tidx_lebs       %u\n", le32_to_cpu(mst->idx_lebs));
         pr_err("\ttotal_free     %llu\n",
                (unsigned long long)le64_to_cpu(mst->total_free));
         pr_err("\ttotal_dirty    %llu\n",
                (unsigned long long)le64_to_cpu(mst->total_dirty));
         pr_err("\ttotal_used     %llu\n",
                (unsigned long long)le64_to_cpu(mst->total_used));
         pr_err("\ttotal_dead     %llu\n",
                (unsigned long long)le64_to_cpu(mst->total_dead));
         pr_err("\ttotal_dark     %llu\n",
                (unsigned long long)le64_to_cpu(mst->total_dark));
         break;
     }
     case UBIFS_REF_NODE:
     {
         const struct ubifs_ref_node *ref = node;
 
         pr_err("\tlnum           %u\n", le32_to_cpu(ref->lnum));
         pr_err("\toffs           %u\n", le32_to_cpu(ref->offs));
         pr_err("\tjhead          %u\n", le32_to_cpu(ref->jhead));
         break;
     }
     case UBIFS_INO_NODE:
     {
         const struct ubifs_ino_node *ino = node;
 
         key_read(c, &ino->key, &key);
         pr_err("\tkey            %s\n",
                dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
         pr_err("\tcreat_sqnum    %llu\n",
                (unsigned long long)le64_to_cpu(ino->creat_sqnum));
         pr_err("\tsize           %llu\n",
                (unsigned long long)le64_to_cpu(ino->size));
         pr_err("\tnlink          %u\n", le32_to_cpu(ino->nlink));
         pr_err("\tatime          %lld.%u\n",
                (long long)le64_to_cpu(ino->atime_sec),
                le32_to_cpu(ino->atime_nsec));
         pr_err("\tmtime          %lld.%u\n",
                (long long)le64_to_cpu(ino->mtime_sec),
                le32_to_cpu(ino->mtime_nsec));
         pr_err("\tctime          %lld.%u\n",
                (long long)le64_to_cpu(ino->ctime_sec),
                le32_to_cpu(ino->ctime_nsec));
         pr_err("\tuid            %u\n", le32_to_cpu(ino->uid));
         pr_err("\tgid            %u\n", le32_to_cpu(ino->gid));
         pr_err("\tmode           %u\n", le32_to_cpu(ino->mode));
         pr_err("\tflags          %#x\n", le32_to_cpu(ino->flags));
         pr_err("\txattr_cnt      %u\n", le32_to_cpu(ino->xattr_cnt));
         pr_err("\txattr_size     %u\n", le32_to_cpu(ino->xattr_size));
         pr_err("\txattr_names    %u\n", le32_to_cpu(ino->xattr_names));
         pr_err("\tcompr_type     %#x\n",
                (int)le16_to_cpu(ino->compr_type));
         pr_err("\tdata len       %u\n", le32_to_cpu(ino->data_len));
         break;
     }
     case UBIFS_DENT_NODE:
     case UBIFS_XENT_NODE:
     {
         const struct ubifs_dent_node *dent = node;
         int nlen = le16_to_cpu(dent->nlen);
 
         key_read(c, &dent->key, &key);
         pr_err("\tkey            %s\n",
                dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
         pr_err("\tinum           %llu\n",
                (unsigned long long)le64_to_cpu(dent->inum));
         pr_err("\ttype           %d\n", (int)dent->type);
         pr_err("\tnlen           %d\n", nlen);
         pr_err("\tname           ");
 
         if (nlen > UBIFS_MAX_NLEN ||
             nlen > safe_len - UBIFS_DENT_NODE_SZ)
             pr_err("(bad name length, not printing, bad or corrupted node)");
         else {
             for (i = 0; i < nlen && dent->name[i]; i++)
                 pr_cont("%c", isprint(dent->name[i]) ?
                     dent->name[i] : '?');
         }
         pr_cont("\n");
 
         break;
     }
     case UBIFS_DATA_NODE:
     {
         const struct ubifs_data_node *dn = node;
 
         key_read(c, &dn->key, &key);
         pr_err("\tkey            %s\n",
                dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
         pr_err("\tsize           %u\n", le32_to_cpu(dn->size));
         pr_err("\tcompr_typ      %d\n",
                (int)le16_to_cpu(dn->compr_type));
         pr_err("\tdata size      %u\n",
                le32_to_cpu(ch->len) - (unsigned int)UBIFS_DATA_NODE_SZ);
         pr_err("\tdata (length = %d):\n",
                safe_len - (int)UBIFS_DATA_NODE_SZ);
         print_hex_dump(KERN_ERR, "\t", DUMP_PREFIX_OFFSET, 32, 1,
                    (void *)&dn->data,
                    safe_len - (int)UBIFS_DATA_NODE_SZ, 0);
         break;
     }
     case UBIFS_TRUN_NODE:
     {
         const struct ubifs_trun_node *trun = node;
 
         pr_err("\tinum           %u\n", le32_to_cpu(trun->inum));
         pr_err("\told_size       %llu\n",
                (unsigned long long)le64_to_cpu(trun->old_size));
         pr_err("\tnew_size       %llu\n",
                (unsigned long long)le64_to_cpu(trun->new_size));
         break;
     }
     case UBIFS_IDX_NODE:
     {
         const struct ubifs_idx_node *idx = node;
         int max_child_cnt = (safe_len - UBIFS_IDX_NODE_SZ) /
                     (ubifs_idx_node_sz(c, 1) -
                     UBIFS_IDX_NODE_SZ);
 
         n = min_t(int, le16_to_cpu(idx->child_cnt), max_child_cnt);
         pr_err("\tchild_cnt      %d\n", (int)le16_to_cpu(idx->child_cnt));
         pr_err("\tlevel          %d\n", (int)le16_to_cpu(idx->level));
         pr_err("\tBranches:\n");
 
         for (i = 0; i < n && i < c->fanout; i++) {
             const struct ubifs_branch *br;
 
             br = ubifs_idx_branch(c, idx, i);
             key_read(c, &br->key, &key);
             pr_err("\t%d: LEB %d:%d len %d key %s\n",
                    i, le32_to_cpu(br->lnum), le32_to_cpu(br->offs),
                    le32_to_cpu(br->len),
                    dbg_snprintf_key(c, &key, key_buf,
                         DBG_KEY_BUF_LEN));
         }
         break;
     }
     case UBIFS_CS_NODE:
         break;
     case UBIFS_ORPH_NODE:
     {
         const struct ubifs_orph_node *orph = node;
 
         pr_err("\tcommit number  %llu\n",
                (unsigned long long)
                 le64_to_cpu(orph->cmt_no) & LLONG_MAX);
         pr_err("\tlast node flag %llu\n",
                (unsigned long long)(le64_to_cpu(orph->cmt_no)) >> 63);
         n = (safe_len - UBIFS_ORPH_NODE_SZ) >> 3;
         pr_err("\t%d orphan inode numbers:\n", n);
         for (i = 0; i < n; i++)
             pr_err("\t  ino %llu\n",
                    (unsigned long long)le64_to_cpu(orph->inos[i]));
         break;
     }
     case UBIFS_AUTH_NODE:
     {
         break;
     }
     default:
         pr_err("node type %d was not recognized\n", type);
     }
 
 out_unlock:
     spin_unlock(&dbg_lock);
 }
 
 void ubifs_dump_budget_req(const struct ubifs_budget_req *req)
 {
     spin_lock(&dbg_lock);
     pr_err("Budgeting request: new_ino %d, dirtied_ino %d\n",
            req->new_ino, req->dirtied_ino);
     pr_err("\tnew_ino_d   %d, dirtied_ino_d %d\n",
            req->new_ino_d, req->dirtied_ino_d);
     pr_err("\tnew_page    %d, dirtied_page %d\n",
            req->new_page, req->dirtied_page);
     pr_err("\tnew_dent    %d, mod_dent     %d\n",
            req->new_dent, req->mod_dent);
     pr_err("\tidx_growth  %d\n", req->idx_growth);
     pr_err("\tdata_growth %d dd_growth     %d\n",
            req->data_growth, req->dd_growth);
     spin_unlock(&dbg_lock);
 }
 
 void ubifs_dump_lstats(const struct ubifs_lp_stats *lst)
 {
     spin_lock(&dbg_lock);
     pr_err("(pid %d) Lprops statistics: empty_lebs %d, idx_lebs  %d\n",
            current->pid, lst->empty_lebs, lst->idx_lebs);
     pr_err("\ttaken_empty_lebs %d, total_free %lld, total_dirty %lld\n",
            lst->taken_empty_lebs, lst->total_free, lst->total_dirty);
     pr_err("\ttotal_used %lld, total_dark %lld, total_dead %lld\n",
            lst->total_used, lst->total_dark, lst->total_dead);
     spin_unlock(&dbg_lock);
 }
 
 void ubifs_dump_budg(struct ubifs_info *c, const struct ubifs_budg_info *bi)
 {
     int i;
     struct rb_node *rb;
     struct ubifs_bud *bud;
     struct ubifs_gced_idx_leb *idx_gc;
     long long available, outstanding, free;
 
     spin_lock(&c->space_lock);
     spin_lock(&dbg_lock);
     pr_err("(pid %d) Budgeting info: data budget sum %lld, total budget sum %lld\n",
            current->pid, bi->data_growth + bi->dd_growth,
            bi->data_growth + bi->dd_growth + bi->idx_growth);
     pr_err("\tbudg_data_growth %lld, budg_dd_growth %lld, budg_idx_growth %lld\n",
            bi->data_growth, bi->dd_growth, bi->idx_growth);
     pr_err("\tmin_idx_lebs %d, old_idx_sz %llu, uncommitted_idx %lld\n",
            bi->min_idx_lebs, bi->old_idx_sz, bi->uncommitted_idx);
     pr_err("\tpage_budget %d, inode_budget %d, dent_budget %d\n",
            bi->page_budget, bi->inode_budget, bi->dent_budget);
     pr_err("\tnospace %u, nospace_rp %u\n", bi->nospace, bi->nospace_rp);
     pr_err("\tdark_wm %d, dead_wm %d, max_idx_node_sz %d\n",
            c->dark_wm, c->dead_wm, c->max_idx_node_sz);
 
     if (bi != &c->bi)
         /*
          * If we are dumping saved budgeting data, do not print
          * additional information which is about the current state, not
          * the old one which corresponded to the saved budgeting data.
          */
         goto out_unlock;
 
     pr_err("\tfreeable_cnt %d, calc_idx_sz %lld, idx_gc_cnt %d\n",
            c->freeable_cnt, c->calc_idx_sz, c->idx_gc_cnt);
     pr_err("\tdirty_pg_cnt %ld, dirty_zn_cnt %ld, clean_zn_cnt %ld\n",
            atomic_long_read(&c->dirty_pg_cnt),
            atomic_long_read(&c->dirty_zn_cnt),
            atomic_long_read(&c->clean_zn_cnt));
     pr_err("\tgc_lnum %d, ihead_lnum %d\n", c->gc_lnum, c->ihead_lnum);
 
     /* If we are in R/O mode, journal heads do not exist */
     if (c->jheads)
         for (i = 0; i < c->jhead_cnt; i++)
             pr_err("\tjhead %s\t LEB %d\n",
                    dbg_jhead(c->jheads[i].wbuf.jhead),
                    c->jheads[i].wbuf.lnum);
     for (rb = rb_first(&c->buds); rb; rb = rb_next(rb)) {
         bud = rb_entry(rb, struct ubifs_bud, rb);
         pr_err("\tbud LEB %d\n", bud->lnum);
     }
     list_for_each_entry(bud, &c->old_buds, list)
         pr_err("\told bud LEB %d\n", bud->lnum);
     list_for_each_entry(idx_gc, &c->idx_gc, list)
         pr_err("\tGC'ed idx LEB %d unmap %d\n",
                idx_gc->lnum, idx_gc->unmap);
     pr_err("\tcommit state %d\n", c->cmt_state);
 
     /* Print budgeting predictions */
     available = ubifs_calc_available(c, c->bi.min_idx_lebs);
     outstanding = c->bi.data_growth + c->bi.dd_growth;
     free = ubifs_get_free_space_nolock(c);
     pr_err("Budgeting predictions:\n");
     pr_err("\tavailable: %lld, outstanding %lld, free %lld\n",
            available, outstanding, free);
 out_unlock:
     spin_unlock(&dbg_lock);
     spin_unlock(&c->space_lock);
 }
 
 void ubifs_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp)
 {
     int i, spc, dark = 0, dead = 0;
     struct rb_node *rb;
     struct ubifs_bud *bud;
 
     spc = lp->free + lp->dirty;
     if (spc < c->dead_wm)
         dead = spc;
     else
         dark = ubifs_calc_dark(c, spc);
 
     if (lp->flags & LPROPS_INDEX)
         pr_err("LEB %-7d free %-8d dirty %-8d used %-8d free + dirty %-8d flags %#x (",
                lp->lnum, lp->free, lp->dirty, c->leb_size - spc, spc,
                lp->flags);
     else
         pr_err("LEB %-7d free %-8d dirty %-8d used %-8d free + dirty %-8d dark %-4d dead %-4d nodes fit %-3d flags %#-4x (",
                lp->lnum, lp->free, lp->dirty, c->leb_size - spc, spc,
                dark, dead, (int)(spc / UBIFS_MAX_NODE_SZ), lp->flags);
 
     if (lp->flags & LPROPS_TAKEN) {
         if (lp->flags & LPROPS_INDEX)
             pr_cont("index, taken");
         else
             pr_cont("taken");
     } else {
         const char *s;
 
         if (lp->flags & LPROPS_INDEX) {
             switch (lp->flags & LPROPS_CAT_MASK) {
             case LPROPS_DIRTY_IDX:
                 s = "dirty index";
                 break;
             case LPROPS_FRDI_IDX:
                 s = "freeable index";
                 break;
             default:
                 s = "index";
             }
         } else {
             switch (lp->flags & LPROPS_CAT_MASK) {
             case LPROPS_UNCAT:
                 s = "not categorized";
                 break;
             case LPROPS_DIRTY:
                 s = "dirty";
                 break;
             case LPROPS_FREE:
                 s = "free";
                 break;
             case LPROPS_EMPTY:
                 s = "empty";
                 break;
             case LPROPS_FREEABLE:
                 s = "freeable";
                 break;
             default:
                 s = NULL;
                 break;
             }
         }
         pr_cont("%s", s);
     }
 
     for (rb = rb_first((struct rb_root *)&c->buds); rb; rb = rb_next(rb)) {
         bud = rb_entry(rb, struct ubifs_bud, rb);
         if (bud->lnum == lp->lnum) {
             int head = 0;
             for (i = 0; i < c->jhead_cnt; i++) {
                 /*
                  * Note, if we are in R/O mode or in the middle
                  * of mounting/re-mounting, the write-buffers do
                  * not exist.
                  */
                 if (c->jheads &&
                     lp->lnum == c->jheads[i].wbuf.lnum) {
                     pr_cont(", jhead %s", dbg_jhead(i));
                     head = 1;
                 }
             }
             if (!head)
                 pr_cont(", bud of jhead %s",
                        dbg_jhead(bud->jhead));
         }
     }
     if (lp->lnum == c->gc_lnum)
         pr_cont(", GC LEB");
     pr_cont(")\n");
 }
 
 void ubifs_dump_lprops(struct ubifs_info *c)
 {
     int lnum, err;
     struct ubifs_lprops lp;
     struct ubifs_lp_stats lst;
 
     pr_err("(pid %d) start dumping LEB properties\n", current->pid);
     ubifs_get_lp_stats(c, &lst);
     ubifs_dump_lstats(&lst);
 
     for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) {
         err = ubifs_read_one_lp(c, lnum, &lp);
         if (err) {
             ubifs_err(c, "cannot read lprops for LEB %d", lnum);
             continue;
         }
 
         ubifs_dump_lprop(c, &lp);
     }
     pr_err("(pid %d) finish dumping LEB properties\n", current->pid);
 }
 
 void ubifs_dump_lpt_info(struct ubifs_info *c)
 {
     int i;
 
     spin_lock(&dbg_lock);
     pr_err("(pid %d) dumping LPT information\n", current->pid);
     pr_err("\tlpt_sz:        %lld\n", c->lpt_sz);
     pr_err("\tpnode_sz:      %d\n", c->pnode_sz);
     pr_err("\tnnode_sz:      %d\n", c->nnode_sz);
     pr_err("\tltab_sz:       %d\n", c->ltab_sz);
     pr_err("\tlsave_sz:      %d\n", c->lsave_sz);
     pr_err("\tbig_lpt:       %u\n", c->big_lpt);
     pr_err("\tlpt_hght:      %d\n", c->lpt_hght);
     pr_err("\tpnode_cnt:     %d\n", c->pnode_cnt);
     pr_err("\tnnode_cnt:     %d\n", c->nnode_cnt);
     pr_err("\tdirty_pn_cnt:  %d\n", c->dirty_pn_cnt);
     pr_err("\tdirty_nn_cnt:  %d\n", c->dirty_nn_cnt);
     pr_err("\tlsave_cnt:     %d\n", c->lsave_cnt);
     pr_err("\tspace_bits:    %d\n", c->space_bits);
     pr_err("\tlpt_lnum_bits: %d\n", c->lpt_lnum_bits);
     pr_err("\tlpt_offs_bits: %d\n", c->lpt_offs_bits);
     pr_err("\tlpt_spc_bits:  %d\n", c->lpt_spc_bits);
     pr_err("\tpcnt_bits:     %d\n", c->pcnt_bits);
     pr_err("\tlnum_bits:     %d\n", c->lnum_bits);
     pr_err("\tLPT root is at %d:%d\n", c->lpt_lnum, c->lpt_offs);
     pr_err("\tLPT head is at %d:%d\n",
            c->nhead_lnum, c->nhead_offs);
     pr_err("\tLPT ltab is at %d:%d\n", c->ltab_lnum, c->ltab_offs);
     if (c->big_lpt)
         pr_err("\tLPT lsave is at %d:%d\n",
                c->lsave_lnum, c->lsave_offs);
     for (i = 0; i < c->lpt_lebs; i++)
         pr_err("\tLPT LEB %d free %d dirty %d tgc %d cmt %d\n",
                i + c->lpt_first, c->ltab[i].free, c->ltab[i].dirty,
                c->ltab[i].tgc, c->ltab[i].cmt);
     spin_unlock(&dbg_lock);
 }
 
 void ubifs_dump_leb(const struct ubifs_info *c, int lnum)
 {
     struct ubifs_scan_leb *sleb;
     struct ubifs_scan_node *snod;
     void *buf;
 
     pr_err("(pid %d) start dumping LEB %d\n", current->pid, lnum);
 
     buf = __vmalloc(c->leb_size, GFP_NOFS);
     if (!buf) {
         ubifs_err(c, "cannot allocate memory for dumping LEB %d", lnum);
         return;
     }
 
     sleb = ubifs_scan(c, lnum, 0, buf, 0);
     if (IS_ERR(sleb)) {
         ubifs_err(c, "scan error %d", (int)PTR_ERR(sleb));
         goto out;
     }
 
     pr_err("LEB %d has %d nodes ending at %d\n", lnum,
            sleb->nodes_cnt, sleb->endpt);
 
     list_for_each_entry(snod, &sleb->nodes, list) {
         cond_resched();
         pr_err("Dumping node at LEB %d:%d len %d\n", lnum,
                snod->offs, snod->len);
         ubifs_dump_node(c, snod->node, c->leb_size - snod->offs);
     }
 
     pr_err("(pid %d) finish dumping LEB %d\n", current->pid, lnum);
     ubifs_scan_destroy(sleb);
 
 out:
     vfree(buf);
     return;
 }
 
 void ubifs_dump_znode(const struct ubifs_info *c,
               const struct ubifs_znode *znode)
 {
     int n;
     const struct ubifs_zbranch *zbr;
     char key_buf[DBG_KEY_BUF_LEN];
 
     spin_lock(&dbg_lock);
     if (znode->parent)
         zbr = &znode->parent->zbranch[znode->iip];
     else
         zbr = &c->zroot;
 
     pr_err("znode %p, LEB %d:%d len %d parent %p iip %d level %d child_cnt %d flags %lx\n",
            znode, zbr->lnum, zbr->offs, zbr->len, znode->parent, znode->iip,
            znode->level, znode->child_cnt, znode->flags);
 
     if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
         spin_unlock(&dbg_lock);
         return;
     }
 
     pr_err("zbranches:\n");
     for (n = 0; n < znode->child_cnt; n++) {
         zbr = &znode->zbranch[n];
         if (znode->level > 0)
             pr_err("\t%d: znode %p LEB %d:%d len %d key %s\n",
                    n, zbr->znode, zbr->lnum, zbr->offs, zbr->len,
                    dbg_snprintf_key(c, &zbr->key, key_buf,
                         DBG_KEY_BUF_LEN));
         else
             pr_err("\t%d: LNC %p LEB %d:%d len %d key %s\n",
                    n, zbr->znode, zbr->lnum, zbr->offs, zbr->len,
                    dbg_snprintf_key(c, &zbr->key, key_buf,
                         DBG_KEY_BUF_LEN));
     }
     spin_unlock(&dbg_lock);
 }
 
 void ubifs_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
 {
     int i;
 
     pr_err("(pid %d) start dumping heap cat %d (%d elements)\n",
            current->pid, cat, heap->cnt);
     for (i = 0; i < heap->cnt; i++) {
         struct ubifs_lprops *lprops = heap->arr[i];
 
         pr_err("\t%d. LEB %d hpos %d free %d dirty %d flags %d\n",
                i, lprops->lnum, lprops->hpos, lprops->free,
                lprops->dirty, lprops->flags);
     }
     pr_err("(pid %d) finish dumping heap\n", current->pid);
 }
 
 void ubifs_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
               struct ubifs_nnode *parent, int iip)
 {
     int i;
 
     pr_err("(pid %d) dumping pnode:\n", current->pid);
     pr_err("\taddress %zx parent %zx cnext %zx\n",
            (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);
     pr_err("\tflags %lu iip %d level %d num %d\n",
            pnode->flags, iip, pnode->level, pnode->num);
     for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
         struct ubifs_lprops *lp = &pnode->lprops[i];
 
         pr_err("\t%d: free %d dirty %d flags %d lnum %d\n",
                i, lp->free, lp->dirty, lp->flags, lp->lnum);
     }
 }
 
 void ubifs_dump_tnc(struct ubifs_info *c)
 {
     struct ubifs_znode *znode;
     int level;
 
     pr_err("\n");
     pr_err("(pid %d) start dumping TNC tree\n", current->pid);
     znode = ubifs_tnc_levelorder_next(c, c->zroot.znode, NULL);
     level = znode->level;
     pr_err("== Level %d ==\n", level);
     while (znode) {
         if (level != znode->level) {
             level = znode->level;
             pr_err("== Level %d ==\n", level);
         }
         ubifs_dump_znode(c, znode);
         znode = ubifs_tnc_levelorder_next(c, c->zroot.znode, znode);
     }
     pr_err("(pid %d) finish dumping TNC tree\n", current->pid);
 }
 
 static int dump_znode(struct ubifs_info *c, struct ubifs_znode *znode,
               void *priv)
 {
     ubifs_dump_znode(c, znode);
     return 0;
 }
 
 /**
  * ubifs_dump_index - dump the on-flash index.
  * @c: UBIFS file-system description object
  *
  * This function dumps whole UBIFS indexing B-tree, unlike 'ubifs_dump_tnc()'
  * which dumps only in-memory znodes and does not read znodes which from flash.
  */
 void ubifs_dump_index(struct ubifs_info *c)
 {
     dbg_walk_index(c, NULL, dump_znode, NULL);
 }
 
 /**
  * dbg_save_space_info - save information about flash space.
  * @c: UBIFS file-system description object
  *
  * This function saves information about UBIFS free space, dirty space, etc, in
  * order to check it later.
  */
 void dbg_save_space_info(struct ubifs_info *c)
 {
     struct ubifs_debug_info *d = c->dbg;
     int freeable_cnt;
 
     spin_lock(&c->space_lock);
     memcpy(&d->saved_lst, &c->lst, sizeof(struct ubifs_lp_stats));
     memcpy(&d->saved_bi, &c->bi, sizeof(struct ubifs_budg_info));
     d->saved_idx_gc_cnt = c->idx_gc_cnt;
 
     /*
      * We use a dirty hack here and zero out @c->freeable_cnt, because it
      * affects the free space calculations, and UBIFS might not know about
      * all freeable eraseblocks. Indeed, we know about freeable eraseblocks
      * only when we read their lprops, and we do this only lazily, upon the
      * need. So at any given point of time @c->freeable_cnt might be not
      * exactly accurate.
      *
      * Just one example about the issue we hit when we did not zero
      * @c->freeable_cnt.
      * 1. The file-system is mounted R/O, c->freeable_cnt is %0. We save the
      *    amount of free space in @d->saved_free
      * 2. We re-mount R/W, which makes UBIFS to read the "lsave"
      *    information from flash, where we cache LEBs from various
      *    categories ('ubifs_remount_fs()' -> 'ubifs_lpt_init()'
      *    -> 'lpt_init_wr()' -> 'read_lsave()' -> 'ubifs_lpt_lookup()'
      *    -> 'ubifs_get_pnode()' -> 'update_cats()'
      *    -> 'ubifs_add_to_cat()').
      * 3. Lsave contains a freeable eraseblock, and @c->freeable_cnt
      *    becomes %1.
      * 4. We calculate the amount of free space when the re-mount is
      *    finished in 'dbg_check_space_info()' and it does not match
      *    @d->saved_free.
      */
     freeable_cnt = c->freeable_cnt;
     c->freeable_cnt = 0;
     d->saved_free = ubifs_get_free_space_nolock(c);
     c->freeable_cnt = freeable_cnt;
     spin_unlock(&c->space_lock);
 }
 
 /**
  * dbg_check_space_info - check flash space information.
  * @c: UBIFS file-system description object
  *
  * This function compares current flash space information with the information
  * which was saved when the 'dbg_save_space_info()' function was called.
  * Returns zero if the information has not changed, and %-EINVAL if it has
  * changed.
  */
 int dbg_check_space_info(struct ubifs_info *c)
 {
     struct ubifs_debug_info *d = c->dbg;
     struct ubifs_lp_stats lst;
     long long free;
     int freeable_cnt;
 
     spin_lock(&c->space_lock);
     freeable_cnt = c->freeable_cnt;
     c->freeable_cnt = 0;
     free = ubifs_get_free_space_nolock(c);
     c->freeable_cnt = freeable_cnt;
     spin_unlock(&c->space_lock);
 
     if (free != d->saved_free) {
         ubifs_err(c, "free space changed from %lld to %lld",
               d->saved_free, free);
         goto out;
     }
 
     return 0;
 
 out:
     ubifs_msg(c, "saved lprops statistics dump");
     ubifs_dump_lstats(&d->saved_lst);
     ubifs_msg(c, "saved budgeting info dump");
     ubifs_dump_budg(c, &d->saved_bi);
     ubifs_msg(c, "saved idx_gc_cnt %d", d->saved_idx_gc_cnt);
     ubifs_msg(c, "current lprops statistics dump");
     ubifs_get_lp_stats(c, &lst);
     ubifs_dump_lstats(&lst);
     ubifs_msg(c, "current budgeting info dump");
     ubifs_dump_budg(c, &c->bi);
     dump_stack();
     return -EINVAL;
 }
 
 /**
  * dbg_check_synced_i_size - check synchronized inode size.
  * @c: UBIFS file-system description object
  * @inode: inode to check
  *
  * If inode is clean, synchronized inode size has to be equivalent to current
  * inode size. This function has to be called only for locked inodes (@i_mutex
  * has to be locked). Returns %0 if synchronized inode size if correct, and
  * %-EINVAL if not.
  */
 int dbg_check_synced_i_size(const struct ubifs_info *c, struct inode *inode)
 {
     int err = 0;
     struct ubifs_inode *ui = ubifs_inode(inode);
 
     if (!dbg_is_chk_gen(c))
         return 0;
     if (!S_ISREG(inode->i_mode))
         return 0;
 
     mutex_lock(&ui->ui_mutex);
     spin_lock(&ui->ui_lock);
     if (ui->ui_size != ui->synced_i_size && !ui->dirty) {
         ubifs_err(c, "ui_size is %lld, synced_i_size is %lld, but inode is clean",
               ui->ui_size, ui->synced_i_size);
         ubifs_err(c, "i_ino %lu, i_mode %#x, i_size %lld", inode->i_ino,
               inode->i_mode, i_size_read(inode));
         dump_stack();
         err = -EINVAL;
     }
     spin_unlock(&ui->ui_lock);
     mutex_unlock(&ui->ui_mutex);
     return err;
 }
 
 /*
  * dbg_check_dir - check directory inode size and link count.
  * @c: UBIFS file-system description object
  * @dir: the directory to calculate size for
  * @size: the result is returned here
  *
  * This function makes sure that directory size and link count are correct.
  * Returns zero in case of success and a negative error code in case of
  * failure.
  *
  * Note, it is good idea to make sure the @dir->i_mutex is locked before
  * calling this function.
  */
 int dbg_check_dir(struct ubifs_info *c, const struct inode *dir)
 {
     unsigned int nlink = 2;
     union ubifs_key key;
     struct ubifs_dent_node *dent, *pdent = NULL;
     struct fscrypt_name nm = {0};
     loff_t size = UBIFS_INO_NODE_SZ;
 
     if (!dbg_is_chk_gen(c))
         return 0;
 
     if (!S_ISDIR(dir->i_mode))
         return 0;
 
     lowest_dent_key(c, &key, dir->i_ino);
     while (1) {
         int err;
 
         dent = ubifs_tnc_next_ent(c, &key, &nm);
         if (IS_ERR(dent)) {
             err = PTR_ERR(dent);
             if (err == -ENOENT)
                 break;
             kfree(pdent);
             return err;
         }
 
         fname_name(&nm) = dent->name;
         fname_len(&nm) = le16_to_cpu(dent->nlen);
         size += CALC_DENT_SIZE(fname_len(&nm));
         if (dent->type == UBIFS_ITYPE_DIR)
             nlink += 1;
         kfree(pdent);
         pdent = dent;
         key_read(c, &dent->key, &key);
     }
     kfree(pdent);
 
     if (i_size_read(dir) != size) {
         ubifs_err(c, "directory inode %lu has size %llu, but calculated size is %llu",
               dir->i_ino, (unsigned long long)i_size_read(dir),
               (unsigned long long)size);
         ubifs_dump_inode(c, dir);
         dump_stack();
         return -EINVAL;
     }
     if (dir->i_nlink != nlink) {
         ubifs_err(c, "directory inode %lu has nlink %u, but calculated nlink is %u",
               dir->i_ino, dir->i_nlink, nlink);
         ubifs_dump_inode(c, dir);
         dump_stack();
         return -EINVAL;
     }
 
     return 0;
 }
 
 /**
  * dbg_check_key_order - make sure that colliding keys are properly ordered.
  * @c: UBIFS file-system description object
  * @zbr1: first zbranch
  * @zbr2: following zbranch
  *
  * In UBIFS indexing B-tree colliding keys has to be sorted in binary order of
  * names of the direntries/xentries which are referred by the keys. This
  * function reads direntries/xentries referred by @zbr1 and @zbr2 and makes
  * sure the name of direntry/xentry referred by @zbr1 is less than
  * direntry/xentry referred by @zbr2. Returns zero if this is true, %1 if not,
  * and a negative error code in case of failure.
  */
 static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
                    struct ubifs_zbranch *zbr2)
 {
     int err, nlen1, nlen2, cmp;
     struct ubifs_dent_node *dent1, *dent2;
     union ubifs_key key;
     char key_buf[DBG_KEY_BUF_LEN];
 
     ubifs_assert(c, !keys_cmp(c, &zbr1->key, &zbr2->key));
     dent1 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
     if (!dent1)
         return -ENOMEM;
     dent2 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
     if (!dent2) {
         err = -ENOMEM;
         goto out_free;
     }
 
     err = ubifs_tnc_read_node(c, zbr1, dent1);
     if (err)
         goto out_free;
     err = ubifs_validate_entry(c, dent1);
     if (err)
         goto out_free;
 
     err = ubifs_tnc_read_node(c, zbr2, dent2);
     if (err)
         goto out_free;
     err = ubifs_validate_entry(c, dent2);
     if (err)
         goto out_free;
 
     /* Make sure node keys are the same as in zbranch */
     err = 1;
     key_read(c, &dent1->key, &key);
     if (keys_cmp(c, &zbr1->key, &key)) {
         ubifs_err(c, "1st entry at %d:%d has key %s", zbr1->lnum,
               zbr1->offs, dbg_snprintf_key(c, &key, key_buf,
                                DBG_KEY_BUF_LEN));
         ubifs_err(c, "but it should have key %s according to tnc",
               dbg_snprintf_key(c, &zbr1->key, key_buf,
                        DBG_KEY_BUF_LEN));
         ubifs_dump_node(c, dent1, UBIFS_MAX_DENT_NODE_SZ);
         goto out_free;
     }
 
     key_read(c, &dent2->key, &key);
     if (keys_cmp(c, &zbr2->key, &key)) {
         ubifs_err(c, "2nd entry at %d:%d has key %s", zbr1->lnum,
               zbr1->offs, dbg_snprintf_key(c, &key, key_buf,
                                DBG_KEY_BUF_LEN));
         ubifs_err(c, "but it should have key %s according to tnc",
               dbg_snprintf_key(c, &zbr2->key, key_buf,
                        DBG_KEY_BUF_LEN));
         ubifs_dump_node(c, dent2, UBIFS_MAX_DENT_NODE_SZ);
         goto out_free;
     }
 
     nlen1 = le16_to_cpu(dent1->nlen);
     nlen2 = le16_to_cpu(dent2->nlen);
 
     cmp = memcmp(dent1->name, dent2->name, min_t(int, nlen1, nlen2));
     if (cmp < 0 || (cmp == 0 && nlen1 < nlen2)) {
         err = 0;
         goto out_free;
     }
     if (cmp == 0 && nlen1 == nlen2)
         ubifs_err(c, "2 xent/dent nodes with the same name");
     else
         ubifs_err(c, "bad order of colliding key %s",
               dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
 
     ubifs_msg(c, "first node at %d:%d\n", zbr1->lnum, zbr1->offs);
     ubifs_dump_node(c, dent1, UBIFS_MAX_DENT_NODE_SZ);
     ubifs_msg(c, "second node at %d:%d\n", zbr2->lnum, zbr2->offs);
     ubifs_dump_node(c, dent2, UBIFS_MAX_DENT_NODE_SZ);
 
 out_free:
     kfree(dent2);
     kfree(dent1);
     return err;
 }
 
 /**
  * dbg_check_znode - check if znode is all right.
  * @c: UBIFS file-system description object
  * @zbr: zbranch which points to this znode
  *
  * This function makes sure that znode referred to by @zbr is all right.
  * Returns zero if it is, and %-EINVAL if it is not.
  */
 static int dbg_check_znode(struct ubifs_info *c, struct ubifs_zbranch *zbr)
 {
     struct ubifs_znode *znode = zbr->znode;
     struct ubifs_znode *zp = znode->parent;
     int n, err, cmp;
 
     if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
         err = 1;
         goto out;
     }
     if (znode->level < 0) {
         err = 2;
         goto out;
     }
     if (znode->iip < 0 || znode->iip >= c->fanout) {
         err = 3;
         goto out;
     }
 
     if (zbr->len == 0)
         /* Only dirty zbranch may have no on-flash nodes */
         if (!ubifs_zn_dirty(znode)) {
             err = 4;
             goto out;
         }
 
     if (ubifs_zn_dirty(znode)) {
         /*
          * If znode is dirty, its parent has to be dirty as well. The
          * order of the operation is important, so we have to have
          * memory barriers.
          */
         smp_mb();
         if (zp && !ubifs_zn_dirty(zp)) {
             /*
              * The dirty flag is atomic and is cleared outside the
              * TNC mutex, so znode's dirty flag may now have
              * been cleared. The child is always cleared before the
              * parent, so we just need to check again.
              */
             smp_mb();
             if (ubifs_zn_dirty(znode)) {
                 err = 5;
                 goto out;
             }
         }
     }
 
     if (zp) {
         const union ubifs_key *min, *max;
 
         if (znode->level != zp->level - 1) {
             err = 6;
             goto out;
         }
 
         /* Make sure the 'parent' pointer in our znode is correct */
         err = ubifs_search_zbranch(c, zp, &zbr->key, &n);
         if (!err) {
             /* This zbranch does not exist in the parent */
             err = 7;
             goto out;
         }
 
         if (znode->iip >= zp->child_cnt) {
             err = 8;
             goto out;
         }
 
         if (znode->iip != n) {
             /* This may happen only in case of collisions */
             if (keys_cmp(c, &zp->zbranch[n].key,
                      &zp->zbranch[znode->iip].key)) {
                 err = 9;
                 goto out;
             }
             n = znode->iip;
         }
 
         /*
          * Make sure that the first key in our znode is greater than or
          * equal to the key in the pointing zbranch.
          */
         min = &zbr->key;
         cmp = keys_cmp(c, min, &znode->zbranch[0].key);
         if (cmp == 1) {
             err = 10;
             goto out;
         }
 
         if (n + 1 < zp->child_cnt) {
             max = &zp->zbranch[n + 1].key;
 
             /*
              * Make sure the last key in our znode is less or
              * equivalent than the key in the zbranch which goes
              * after our pointing zbranch.
              */
             cmp = keys_cmp(c, max,
                 &znode->zbranch[znode->child_cnt - 1].key);
             if (cmp == -1) {
                 err = 11;
                 goto out;
             }
         }
     } else {
         /* This may only be root znode */
         if (zbr != &c->zroot) {
             err = 12;
             goto out;
         }
     }
 
     /*
      * Make sure that next key is greater or equivalent then the previous
      * one.
      */
     for (n = 1; n < znode->child_cnt; n++) {
         cmp = keys_cmp(c, &znode->zbranch[n - 1].key,
                    &znode->zbranch[n].key);
         if (cmp > 0) {
             err = 13;
             goto out;
         }
         if (cmp == 0) {
             /* This can only be keys with colliding hash */
             if (!is_hash_key(c, &znode->zbranch[n].key)) {
                 err = 14;
                 goto out;
             }
 
             if (znode->level != 0 || c->replaying)
                 continue;
 
             /*
              * Colliding keys should follow binary order of
              * corresponding xentry/dentry names.
              */
             err = dbg_check_key_order(c, &znode->zbranch[n - 1],
                           &znode->zbranch[n]);
             if (err < 0)
                 return err;
             if (err) {
                 err = 15;
                 goto out;
             }
         }
     }
 
     for (n = 0; n < znode->child_cnt; n++) {
         if (!znode->zbranch[n].znode &&
             (znode->zbranch[n].lnum == 0 ||
              znode->zbranch[n].len == 0)) {
             err = 16;
             goto out;
         }
 
         if (znode->zbranch[n].lnum != 0 &&
             znode->zbranch[n].len == 0) {
             err = 17;
             goto out;
         }
 
         if (znode->zbranch[n].lnum == 0 &&
             znode->zbranch[n].len != 0) {
             err = 18;
             goto out;
         }
 
         if (znode->zbranch[n].lnum == 0 &&
             znode->zbranch[n].offs != 0) {
             err = 19;
             goto out;
         }
 
         if (znode->level != 0 && znode->zbranch[n].znode)
             if (znode->zbranch[n].znode->parent != znode) {
                 err = 20;
                 goto out;
             }
     }
 
     return 0;
 
 out:
     ubifs_err(c, "failed, error %d", err);
     ubifs_msg(c, "dump of the znode");
     ubifs_dump_znode(c, znode);
     if (zp) {
         ubifs_msg(c, "dump of the parent znode");
         ubifs_dump_znode(c, zp);
     }
     dump_stack();
     return -EINVAL;
 }
 
 /**
  * dbg_check_tnc - check TNC tree.
  * @c: UBIFS file-system description object
  * @extra: do extra checks that are possible at start commit
  *
  * This function traverses whole TNC tree and checks every znode. Returns zero
  * if everything is all right and %-EINVAL if something is wrong with TNC.
  */
 int dbg_check_tnc(struct ubifs_info *c, int extra)
 {
     struct ubifs_znode *znode;
     long clean_cnt = 0, dirty_cnt = 0;
     int err, last;
 
     if (!dbg_is_chk_index(c))
         return 0;
 
     ubifs_assert(c, mutex_is_locked(&c->tnc_mutex));
     if (!c->zroot.znode)
         return 0;
 
     znode = ubifs_tnc_postorder_first(c->zroot.znode);
     while (1) {
         struct ubifs_znode *prev;
         struct ubifs_zbranch *zbr;
 
         if (!znode->parent)
             zbr = &c->zroot;
         else
             zbr = &znode->parent->zbranch[znode->iip];
 
         err = dbg_check_znode(c, zbr);
         if (err)
             return err;
 
         if (extra) {
             if (ubifs_zn_dirty(znode))
                 dirty_cnt += 1;
             else
                 clean_cnt += 1;
         }
 
         prev = znode;
         znode = ubifs_tnc_postorder_next(c, znode);
         if (!znode)
             break;
 
         /*
          * If the last key of this znode is equivalent to the first key
          * of the next znode (collision), then check order of the keys.
          */
         last = prev->child_cnt - 1;
         if (prev->level == 0 && znode->level == 0 && !c->replaying &&
             !keys_cmp(c, &prev->zbranch[last].key,
                   &znode->zbranch[0].key)) {
             err = dbg_check_key_order(c, &prev->zbranch[last],
                           &znode->zbranch[0]);
             if (err < 0)
                 return err;
             if (err) {
                 ubifs_msg(c, "first znode");
                 ubifs_dump_znode(c, prev);
                 ubifs_msg(c, "second znode");
                 ubifs_dump_znode(c, znode);
                 return -EINVAL;
             }
         }
     }
 
     if (extra) {
         if (clean_cnt != atomic_long_read(&c->clean_zn_cnt)) {
             ubifs_err(c, "incorrect clean_zn_cnt %ld, calculated %ld",
                   atomic_long_read(&c->clean_zn_cnt),
                   clean_cnt);
             return -EINVAL;
         }
         if (dirty_cnt != atomic_long_read(&c->dirty_zn_cnt)) {
             ubifs_err(c, "incorrect dirty_zn_cnt %ld, calculated %ld",
                   atomic_long_read(&c->dirty_zn_cnt),
                   dirty_cnt);
             return -EINVAL;
         }
     }
 
     return 0;
 }
 
 /**
  * dbg_walk_index - walk the on-flash index.
  * @c: UBIFS file-system description object
  * @leaf_cb: called for each leaf node
  * @znode_cb: called for each indexing node
  * @priv: private data which is passed to callbacks
  *
  * This function walks the UBIFS index and calls the @leaf_cb for each leaf
  * node and @znode_cb for each indexing node. Returns zero in case of success
  * and a negative error code in case of failure.
  *
  * It would be better if this function removed every znode it pulled to into
  * the TNC, so that the behavior more closely matched the non-debugging
  * behavior.
  */
 int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
            dbg_znode_callback znode_cb, void *priv)
 {
     int err;
     struct ubifs_zbranch *zbr;
     struct ubifs_znode *znode, *child;
 
     mutex_lock(&c->tnc_mutex);
     /* If the root indexing node is not in TNC - pull it */
     if (!c->zroot.znode) {
         c->zroot.znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
         if (IS_ERR(c->zroot.znode)) {
             err = PTR_ERR(c->zroot.znode);
             c->zroot.znode = NULL;
             goto out_unlock;
         }
     }
 
     /*
      * We are going to traverse the indexing tree in the postorder manner.
      * Go down and find the leftmost indexing node where we are going to
      * start from.
      */
     znode = c->zroot.znode;
     while (znode->level > 0) {
         zbr = &znode->zbranch[0];
         child = zbr->znode;
         if (!child) {
             child = ubifs_load_znode(c, zbr, znode, 0);
             if (IS_ERR(child)) {
                 err = PTR_ERR(child);
                 goto out_unlock;
             }
         }
 
         znode = child;
     }
 
     /* Iterate over all indexing nodes */
     while (1) {
         int idx;
 
         cond_resched();
 
         if (znode_cb) {
             err = znode_cb(c, znode, priv);
             if (err) {
                 ubifs_err(c, "znode checking function returned error %d",
                       err);
                 ubifs_dump_znode(c, znode);
                 goto out_dump;
             }
         }
         if (leaf_cb && znode->level == 0) {
             for (idx = 0; idx < znode->child_cnt; idx++) {
                 zbr = &znode->zbranch[idx];
                 err = leaf_cb(c, zbr, priv);
                 if (err) {
                     ubifs_err(c, "leaf checking function returned error %d, for leaf at LEB %d:%d",
                           err, zbr->lnum, zbr->offs);
                     goto out_dump;
                 }
             }
         }
 
         if (!znode->parent)
             break;
 
         idx = znode->iip + 1;
         znode = znode->parent;
         if (idx < znode->child_cnt) {
             /* Switch to the next index in the parent */
             zbr = &znode->zbranch[idx];
             child = zbr->znode;
             if (!child) {
                 child = ubifs_load_znode(c, zbr, znode, idx);
                 if (IS_ERR(child)) {
                     err = PTR_ERR(child);
                     goto out_unlock;
                 }
                 zbr->znode = child;
             }
             znode = child;
         } else
             /*
              * This is the last child, switch to the parent and
              * continue.
              */
             continue;
 
         /* Go to the lowest leftmost znode in the new sub-tree */
         while (znode->level > 0) {
             zbr = &znode->zbranch[0];
             child = zbr->znode;
             if (!child) {
                 child = ubifs_load_znode(c, zbr, znode, 0);
                 if (IS_ERR(child)) {
                     err = PTR_ERR(child);
                     goto out_unlock;
                 }
                 zbr->znode = child;
             }
             znode = child;
         }
     }
 
     mutex_unlock(&c->tnc_mutex);
     return 0;
 
 out_dump:
     if (znode->parent)
         zbr = &znode->parent->zbranch[znode->iip];
     else
         zbr = &c->zroot;
     ubifs_msg(c, "dump of znode at LEB %d:%d", zbr->lnum, zbr->offs);
     ubifs_dump_znode(c, znode);
 out_unlock:
     mutex_unlock(&c->tnc_mutex);
     return err;
 }
 
 /**
  * add_size - add znode size to partially calculated index size.
  * @c: UBIFS file-system description object
  * @znode: znode to add size for
  * @priv: partially calculated index size
  *
  * This is a helper function for 'dbg_check_idx_size()' which is called for
  * every indexing node and adds its size to the 'long long' variable pointed to
  * by @priv.
  */
 static int add_size(struct ubifs_info *c, struct ubifs_znode *znode, void *priv)
 {
     long long *idx_size = priv;
     int add;
 
     add = ubifs_idx_node_sz(c, znode->child_cnt);
     add = ALIGN(add, 8);
     *idx_size += add;
     return 0;
 }
 
 /**
  * dbg_check_idx_size - check index size.
  * @c: UBIFS file-system description object
  * @idx_size: size to check
  *
  * This function walks the UBIFS index, calculates its size and checks that the
  * size is equivalent to @idx_size. Returns zero in case of success and a
  * negative error code in case of failure.
  */
 int dbg_check_idx_size(struct ubifs_info *c, long long idx_size)
 {
     int err;
     long long calc = 0;
 
     if (!dbg_is_chk_index(c))
         return 0;
 
     err = dbg_walk_index(c, NULL, add_size, &calc);
     if (err) {
         ubifs_err(c, "error %d while walking the index", err);
         return err;
     }
 
     if (calc != idx_size) {
         ubifs_err(c, "index size check failed: calculated size is %lld, should be %lld",
               calc, idx_size);
         dump_stack();
         return -EINVAL;
     }
 
     return 0;
 }
 
 /**
  * struct fsck_inode - information about an inode used when checking the file-system.
  * @rb: link in the RB-tree of inodes
  * @inum: inode number
  * @mode: inode type, permissions, etc
  * @nlink: inode link count
  * @xattr_cnt: count of extended attributes
  * @references: how many directory/xattr entries refer this inode (calculated
  *              while walking the index)
  * @calc_cnt: for directory inode count of child directories
  * @size: inode size (read from on-flash inode)
  * @xattr_sz: summary size of all extended attributes (read from on-flash
  *            inode)
  * @calc_sz: for directories calculated directory size
  * @calc_xcnt: count of extended attributes
  * @calc_xsz: calculated summary size of all extended attributes
  * @xattr_nms: sum of lengths of all extended attribute names belonging to this
  *             inode (read from on-flash inode)
  * @calc_xnms: calculated sum of lengths of all extended attribute names
  */
 struct fsck_inode {
     struct rb_node rb;
     ino_t inum;
     umode_t mode;
     unsigned int nlink;
     unsigned int xattr_cnt;
     int references;
     int calc_cnt;
     long long size;
     unsigned int xattr_sz;
     long long calc_sz;
     long long calc_xcnt;
     long long calc_xsz;
     unsigned int xattr_nms;
     long long calc_xnms;
 };
 
 /**
  * struct fsck_data - private FS checking information.
  * @inodes: RB-tree of all inodes (contains @struct fsck_inode objects)
  */
 struct fsck_data {
     struct rb_root inodes;
 };
 
 /**
  * add_inode - add inode information to RB-tree of inodes.
  * @c: UBIFS file-system description object
  * @fsckd: FS checking information
  * @ino: raw UBIFS inode to add
  *
  * This is a helper function for 'check_leaf()' which adds information about
  * inode @ino to the RB-tree of inodes. Returns inode information pointer in
  * case of success and a negative error code in case of failure.
  */
 static struct fsck_inode *add_inode(struct ubifs_info *c,
                     struct fsck_data *fsckd,
                     struct ubifs_ino_node *ino)
 {
     struct rb_node **p, *parent = NULL;
     struct fsck_inode *fscki;
     ino_t inum = key_inum_flash(c, &ino->key);
     struct inode *inode;
     struct ubifs_inode *ui;
 
     p = &fsckd->inodes.rb_node;
     while (*p) {
         parent = *p;
         fscki = rb_entry(parent, struct fsck_inode, rb);
         if (inum < fscki->inum)
             p = &(*p)->rb_left;
         else if (inum > fscki->inum)
             p = &(*p)->rb_right;
         else
             return fscki;
     }
 
     if (inum > c->highest_inum) {
         ubifs_err(c, "too high inode number, max. is %lu",
               (unsigned long)c->highest_inum);
         return ERR_PTR(-EINVAL);
     }
 
     fscki = kzalloc(sizeof(struct fsck_inode), GFP_NOFS);
     if (!fscki)
         return ERR_PTR(-ENOMEM);
 
     inode = ilookup(c->vfs_sb, inum);
 
     fscki->inum = inum;
     /*
      * If the inode is present in the VFS inode cache, use it instead of
      * the on-flash inode which might be out-of-date. E.g., the size might
      * be out-of-date. If we do not do this, the following may happen, for
      * example:
      *   1. A power cut happens
      *   2. We mount the file-system R/O, the replay process fixes up the
      *      inode size in the VFS cache, but on on-flash.
      *   3. 'check_leaf()' fails because it hits a data node beyond inode
      *      size.
      */
     if (!inode) {
         fscki->nlink = le32_to_cpu(ino->nlink);
         fscki->size = le64_to_cpu(ino->size);
         fscki->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
         fscki->xattr_sz = le32_to_cpu(ino->xattr_size);
         fscki->xattr_nms = le32_to_cpu(ino->xattr_names);
         fscki->mode = le32_to_cpu(ino->mode);
     } else {
         ui = ubifs_inode(inode);
         fscki->nlink = inode->i_nlink;
         fscki->size = inode->i_size;
         fscki->xattr_cnt = ui->xattr_cnt;
         fscki->xattr_sz = ui->xattr_size;
         fscki->xattr_nms = ui->xattr_names;
         fscki->mode = inode->i_mode;
         iput(inode);
     }
 
     if (S_ISDIR(fscki->mode)) {
         fscki->calc_sz = UBIFS_INO_NODE_SZ;
         fscki->calc_cnt = 2;
     }
 
     rb_link_node(&fscki->rb, parent, p);
     rb_insert_color(&fscki->rb, &fsckd->inodes);
 
     return fscki;
 }
 
 /**
  * search_inode - search inode in the RB-tree of inodes.
  * @fsckd: FS checking information
  * @inum: inode number to search
  *
  * This is a helper function for 'check_leaf()' which searches inode @inum in
  * the RB-tree of inodes and returns an inode information pointer or %NULL if
  * the inode was not found.
  */
 static struct fsck_inode *search_inode(struct fsck_data *fsckd, ino_t inum)
 {
     struct rb_node *p;
     struct fsck_inode *fscki;
 
     p = fsckd->inodes.rb_node;
     while (p) {
         fscki = rb_entry(p, struct fsck_inode, rb);
         if (inum < fscki->inum)
             p = p->rb_left;
         else if (inum > fscki->inum)
             p = p->rb_right;
         else
             return fscki;
     }
     return NULL;
 }
 
 /**
  * read_add_inode - read inode node and add it to RB-tree of inodes.
  * @c: UBIFS file-system description object
  * @fsckd: FS checking information
  * @inum: inode number to read
  *
  * This is a helper function for 'check_leaf()' which finds inode node @inum in
  * the index, reads it, and adds it to the RB-tree of inodes. Returns inode
  * information pointer in case of success and a negative error code in case of
  * failure.
  */
 static struct fsck_inode *read_add_inode(struct ubifs_info *c,
                      struct fsck_data *fsckd, ino_t inum)
 {
     int n, err;
     union ubifs_key key;
     struct ubifs_znode *znode;
     struct ubifs_zbranch *zbr;
     struct ubifs_ino_node *ino;
     struct fsck_inode *fscki;
 
     fscki = search_inode(fsckd, inum);
     if (fscki)
         return fscki;
 
     ino_key_init(c, &key, inum);
     err = ubifs_lookup_level0(c, &key, &znode, &n);
     if (!err) {
         ubifs_err(c, "inode %lu not found in index", (unsigned long)inum);
         return ERR_PTR(-ENOENT);
     } else if (err < 0) {
         ubifs_err(c, "error %d while looking up inode %lu",
               err, (unsigned long)inum);
         return ERR_PTR(err);
     }
 
     zbr = &znode->zbranch[n];
     if (zbr->len < UBIFS_INO_NODE_SZ) {
         ubifs_err(c, "bad node %lu node length %d",
               (unsigned long)inum, zbr->len);
         return ERR_PTR(-EINVAL);
     }
 
     ino = kmalloc(zbr->len, GFP_NOFS);
     if (!ino)
         return ERR_PTR(-ENOMEM);
 
     err = ubifs_tnc_read_node(c, zbr, ino);
     if (err) {
         ubifs_err(c, "cannot read inode node at LEB %d:%d, error %d",
               zbr->lnum, zbr->offs, err);
         kfree(ino);
         return ERR_PTR(err);
     }
 
     fscki = add_inode(c, fsckd, ino);
     kfree(ino);
     if (IS_ERR(fscki)) {
         ubifs_err(c, "error %ld while adding inode %lu node",
               PTR_ERR(fscki), (unsigned long)inum);
         return fscki;
     }
 
     return fscki;
 }
 
 /**
  * check_leaf - check leaf node.
  * @c: UBIFS file-system description object
  * @zbr: zbranch of the leaf node to check
  * @priv: FS checking information
  *
  * This is a helper function for 'dbg_check_filesystem()' which is called for
  * every single leaf node while walking the indexing tree. It checks that the
  * leaf node referred from the indexing tree exists, has correct CRC, and does
  * some other basic validation. This function is also responsible for building
  * an RB-tree of inodes - it adds all inodes into the RB-tree. It also
  * calculates reference count, size, etc for each inode in order to later
  * compare them to the information stored inside the inodes and detect possible
  * inconsistencies. Returns zero in case of success and a negative error code
  * in case of failure.
  */
 static int check_leaf(struct ubifs_info *c, struct ubifs_zbranch *zbr,
               void *priv)
 {
     ino_t inum;
     void *node;
     struct ubifs_ch *ch;
     int err, type = key_type(c, &zbr->key);
     struct fsck_inode *fscki;
 
     if (zbr->len < UBIFS_CH_SZ) {
         ubifs_err(c, "bad leaf length %d (LEB %d:%d)",
               zbr->len, zbr->lnum, zbr->offs);
         return -EINVAL;
     }
 
     node = kmalloc(zbr->len, GFP_NOFS);
     if (!node)
         return -ENOMEM;
 
     err = ubifs_tnc_read_node(c, zbr, node);
     if (err) {
         ubifs_err(c, "cannot read leaf node at LEB %d:%d, error %d",
               zbr->lnum, zbr->offs, err);
         goto out_free;
     }
 
     /* If this is an inode node, add it to RB-tree of inodes */
     if (type == UBIFS_INO_KEY) {
         fscki = add_inode(c, priv, node);
         if (IS_ERR(fscki)) {
             err = PTR_ERR(fscki);
             ubifs_err(c, "error %d while adding inode node", err);
             goto out_dump;
         }
         goto out;
     }
 
     if (type != UBIFS_DENT_KEY && type != UBIFS_XENT_KEY &&
         type != UBIFS_DATA_KEY) {
         ubifs_err(c, "unexpected node type %d at LEB %d:%d",
               type, zbr->lnum, zbr->offs);
         err = -EINVAL;
         goto out_free;
     }
 
     ch = node;
     if (le64_to_cpu(ch->sqnum) > c->max_sqnum) {
         ubifs_err(c, "too high sequence number, max. is %llu",
               c->max_sqnum);
         err = -EINVAL;
         goto out_dump;
     }
 
     if (type == UBIFS_DATA_KEY) {
         long long blk_offs;
         struct ubifs_data_node *dn = node;
 
         ubifs_assert(c, zbr->len >= UBIFS_DATA_NODE_SZ);
 
         /*
          * Search the inode node this data node belongs to and insert
          * it to the RB-tree of inodes.
          */
         inum = key_inum_flash(c, &dn->key);
         fscki = read_add_inode(c, priv, inum);
         if (IS_ERR(fscki)) {
             err = PTR_ERR(fscki);
             ubifs_err(c, "error %d while processing data node and trying to find inode node %lu",
                   err, (unsigned long)inum);
             goto out_dump;
         }
 
         /* Make sure the data node is within inode size */
         blk_offs = key_block_flash(c, &dn->key);
         blk_offs <<= UBIFS_BLOCK_SHIFT;
         blk_offs += le32_to_cpu(dn->size);
         if (blk_offs > fscki->size) {
             ubifs_err(c, "data node at LEB %d:%d is not within inode size %lld",
                   zbr->lnum, zbr->offs, fscki->size);
             err = -EINVAL;
             goto out_dump;
         }
     } else {
         int nlen;
         struct ubifs_dent_node *dent = node;
         struct fsck_inode *fscki1;
 
         ubifs_assert(c, zbr->len >= UBIFS_DENT_NODE_SZ);
 
         err = ubifs_validate_entry(c, dent);
         if (err)
             goto out_dump;
 
         /*
          * Search the inode node this entry refers to and the parent
          * inode node and insert them to the RB-tree of inodes.
          */
         inum = le64_to_cpu(dent->inum);
         fscki = read_add_inode(c, priv, inum);
         if (IS_ERR(fscki)) {
             err = PTR_ERR(fscki);
             ubifs_err(c, "error %d while processing entry node and trying to find inode node %lu",
                   err, (unsigned long)inum);
             goto out_dump;
         }
 
         /* Count how many direntries or xentries refers this inode */
         fscki->references += 1;
 
         inum = key_inum_flash(c, &dent->key);
         fscki1 = read_add_inode(c, priv, inum);
         if (IS_ERR(fscki1)) {
             err = PTR_ERR(fscki1);
             ubifs_err(c, "error %d while processing entry node and trying to find parent inode node %lu",
                   err, (unsigned long)inum);
             goto out_dump;
         }
 
         nlen = le16_to_cpu(dent->nlen);
         if (type == UBIFS_XENT_KEY) {
             fscki1->calc_xcnt += 1;
             fscki1->calc_xsz += CALC_DENT_SIZE(nlen);
             fscki1->calc_xsz += CALC_XATTR_BYTES(fscki->size);
             fscki1->calc_xnms += nlen;
         } else {
             fscki1->calc_sz += CALC_DENT_SIZE(nlen);
             if (dent->type == UBIFS_ITYPE_DIR)
                 fscki1->calc_cnt += 1;
         }
     }
 
 out:
     kfree(node);
     return 0;
 
 out_dump:
     ubifs_msg(c, "dump of node at LEB %d:%d", zbr->lnum, zbr->offs);
     ubifs_dump_node(c, node, zbr->len);
 out_free:
     kfree(node);
     return err;
 }
 
 /**
  * free_inodes - free RB-tree of inodes.
  * @fsckd: FS checking information
  */
 static void free_inodes(struct fsck_data *fsckd)
 {
     struct fsck_inode *fscki, *n;
 
     rbtree_postorder_for_each_entry_safe(fscki, n, &fsckd->inodes, rb)
         kfree(fscki);
 }
 
 /**
  * check_inodes - checks all inodes.
  * @c: UBIFS file-system description object
  * @fsckd: FS checking information
  *
  * This is a helper function for 'dbg_check_filesystem()' which walks the
  * RB-tree of inodes after the index scan has been finished, and checks that
  * inode nlink, size, etc are correct. Returns zero if inodes are fine,
  * %-EINVAL if not, and a negative error code in case of failure.
  */
 static int check_inodes(struct ubifs_info *c, struct fsck_data *fsckd)
 {
     int n, err;
     union ubifs_key key;
     struct ubifs_znode *znode;
     struct ubifs_zbranch *zbr;
     struct ubifs_ino_node *ino;
     struct fsck_inode *fscki;
     struct rb_node *this = rb_first(&fsckd->inodes);
 
     while (this) {
         fscki = rb_entry(this, struct fsck_inode, rb);
         this = rb_next(this);
 
         if (S_ISDIR(fscki->mode)) {
             /*
              * Directories have to have exactly one reference (they
              * cannot have hardlinks), although root inode is an
              * exception.
              */
             if (fscki->inum != UBIFS_ROOT_INO &&
                 fscki->references != 1) {
                 ubifs_err(c, "directory inode %lu has %d direntries which refer it, but should be 1",
                       (unsigned long)fscki->inum,
                       fscki->references);
                 goto out_dump;
             }
             if (fscki->inum == UBIFS_ROOT_INO &&
                 fscki->references != 0) {
                 ubifs_err(c, "root inode %lu has non-zero (%d) direntries which refer it",
                       (unsigned long)fscki->inum,
                       fscki->references);
                 goto out_dump;
             }
             if (fscki->calc_sz != fscki->size) {
                 ubifs_err(c, "directory inode %lu size is %lld, but calculated size is %lld",
                       (unsigned long)fscki->inum,
                       fscki->size, fscki->calc_sz);
                 goto out_dump;
             }
             if (fscki->calc_cnt != fscki->nlink) {
                 ubifs_err(c, "directory inode %lu nlink is %d, but calculated nlink is %d",
                       (unsigned long)fscki->inum,
                       fscki->nlink, fscki->calc_cnt);
                 goto out_dump;
             }
         } else {
             if (fscki->references != fscki->nlink) {
                 ubifs_err(c, "inode %lu nlink is %d, but calculated nlink is %d",
                       (unsigned long)fscki->inum,
                       fscki->nlink, fscki->references);
                 goto out_dump;
             }
         }
         if (fscki->xattr_sz != fscki->calc_xsz) {
             ubifs_err(c, "inode %lu has xattr size %u, but calculated size is %lld",
                   (unsigned long)fscki->inum, fscki->xattr_sz,
                   fscki->calc_xsz);
             goto out_dump;
         }
         if (fscki->xattr_cnt != fscki->calc_xcnt) {
             ubifs_err(c, "inode %lu has %u xattrs, but calculated count is %lld",
                   (unsigned long)fscki->inum,
                   fscki->xattr_cnt, fscki->calc_xcnt);
             goto out_dump;
         }
         if (fscki->xattr_nms != fscki->calc_xnms) {
             ubifs_err(c, "inode %lu has xattr names' size %u, but calculated names' size is %lld",
                   (unsigned long)fscki->inum, fscki->xattr_nms,
                   fscki->calc_xnms);
             goto out_dump;
         }
     }
 
     return 0;
 
 out_dump:
     /* Read the bad inode and dump it */
     ino_key_init(c, &key, fscki->inum);
     err = ubifs_lookup_level0(c, &key, &znode, &n);
     if (!err) {
         ubifs_err(c, "inode %lu not found in index",
               (unsigned long)fscki->inum);
         return -ENOENT;
     } else if (err < 0) {
         ubifs_err(c, "error %d while looking up inode %lu",
               err, (unsigned long)fscki->inum);
         return err;
     }
 
     zbr = &znode->zbranch[n];
     ino = kmalloc(zbr->len, GFP_NOFS);
     if (!ino)
         return -ENOMEM;
 
     err = ubifs_tnc_read_node(c, zbr, ino);
     if (err) {
         ubifs_err(c, "cannot read inode node at LEB %d:%d, error %d",
               zbr->lnum, zbr->offs, err);
         kfree(ino);
         return err;
     }
 
     ubifs_msg(c, "dump of the inode %lu sitting in LEB %d:%d",
           (unsigned long)fscki->inum, zbr->lnum, zbr->offs);
     ubifs_dump_node(c, ino, zbr->len);
     kfree(ino);
     return -EINVAL;
 }
 
 /**
  * dbg_check_filesystem - check the file-system.
  * @c: UBIFS file-system description object
  *
  * This function checks the file system, namely:
  * o makes sure that all leaf nodes exist and their CRCs are correct;
  * o makes sure inode nlink, size, xattr size/count are correct (for all
  *   inodes).
  *
  * The function reads whole indexing tree and all nodes, so it is pretty
  * heavy-weight. Returns zero if the file-system is consistent, %-EINVAL if
  * not, and a negative error code in case of failure.
  */
 int dbg_check_filesystem(struct ubifs_info *c)
 {
     int err;
     struct fsck_data fsckd;
 
     if (!dbg_is_chk_fs(c))
         return 0;
 
     fsckd.inodes = RB_ROOT;
     err = dbg_walk_index(c, check_leaf, NULL, &fsckd);
     if (err)
         goto out_free;
 
     err = check_inodes(c, &fsckd);
     if (err)
         goto out_free;
 
     free_inodes(&fsckd);
     return 0;
 
 out_free:
     ubifs_err(c, "file-system check failed with error %d", err);
     dump_stack();
     free_inodes(&fsckd);
     return err;
 }
 
 /**
  * dbg_check_data_nodes_order - check that list of data nodes is sorted.
  * @c: UBIFS file-system description object
  * @head: the list of nodes ('struct ubifs_scan_node' objects)
  *
  * This function returns zero if the list of data nodes is sorted correctly,
  * and %-EINVAL if not.
  */
 int dbg_check_data_nodes_order(struct ubifs_info *c, struct list_head *head)
 {
     struct list_head *cur;
     struct ubifs_scan_node *sa, *sb;
 
     if (!dbg_is_chk_gen(c))
         return 0;
 
     for (cur = head->next; cur->next != head; cur = cur->next) {
         ino_t inuma, inumb;
         uint32_t blka, blkb;
 
         cond_resched();
         sa = container_of(cur, struct ubifs_scan_node, list);
         sb = container_of(cur->next, struct ubifs_scan_node, list);
 
         if (sa->type != UBIFS_DATA_NODE) {
             ubifs_err(c, "bad node type %d", sa->type);
             ubifs_dump_node(c, sa->node, c->leb_size - sa->offs);
             return -EINVAL;
         }
         if (sb->type != UBIFS_DATA_NODE) {
             ubifs_err(c, "bad node type %d", sb->type);
             ubifs_dump_node(c, sb->node, c->leb_size - sb->offs);
             return -EINVAL;
         }
 
         inuma = key_inum(c, &sa->key);
         inumb = key_inum(c, &sb->key);
 
         if (inuma < inumb)
             continue;
         if (inuma > inumb) {
             ubifs_err(c, "larger inum %lu goes before inum %lu",
                   (unsigned long)inuma, (unsigned long)inumb);
             goto error_dump;
         }
 
         blka = key_block(c, &sa->key);
         blkb = key_block(c, &sb->key);
 
         if (blka > blkb) {
             ubifs_err(c, "larger block %u goes before %u", blka, blkb);
             goto error_dump;
         }
         if (blka == blkb) {
             ubifs_err(c, "two data nodes for the same block");
             goto error_dump;
         }
     }
 
     return 0;
 
 error_dump:
     ubifs_dump_node(c, sa->node, c->leb_size - sa->offs);
     ubifs_dump_node(c, sb->node, c->leb_size - sb->offs);
     return -EINVAL;
 }
 
 /**
  * dbg_check_nondata_nodes_order - check that list of data nodes is sorted.
  * @c: UBIFS file-system description object
  * @head: the list of nodes ('struct ubifs_scan_node' objects)
  *
  * This function returns zero if the list of non-data nodes is sorted correctly,
  * and %-EINVAL if not.
  */
 int dbg_check_nondata_nodes_order(struct ubifs_info *c, struct list_head *head)
 {
     struct list_head *cur;
     struct ubifs_scan_node *sa, *sb;
 
     if (!dbg_is_chk_gen(c))
         return 0;
 
     for (cur = head->next; cur->next != head; cur = cur->next) {
         ino_t inuma, inumb;
         uint32_t hasha, hashb;
 
         cond_resched();
         sa = container_of(cur, struct ubifs_scan_node, list);
         sb = container_of(cur->next, struct ubifs_scan_node, list);
 
         if (sa->type != UBIFS_INO_NODE && sa->type != UBIFS_DENT_NODE &&
             sa->type != UBIFS_XENT_NODE) {
             ubifs_err(c, "bad node type %d", sa->type);
             ubifs_dump_node(c, sa->node, c->leb_size - sa->offs);
             return -EINVAL;
         }
         if (sb->type != UBIFS_INO_NODE && sb->type != UBIFS_DENT_NODE &&
             sb->type != UBIFS_XENT_NODE) {
             ubifs_err(c, "bad node type %d", sb->type);
             ubifs_dump_node(c, sb->node, c->leb_size - sb->offs);
             return -EINVAL;
         }
 
         if (sa->type != UBIFS_INO_NODE && sb->type == UBIFS_INO_NODE) {
             ubifs_err(c, "non-inode node goes before inode node");
             goto error_dump;
         }
 
         if (sa->type == UBIFS_INO_NODE && sb->type != UBIFS_INO_NODE)
             continue;
 
         if (sa->type == UBIFS_INO_NODE && sb->type == UBIFS_INO_NODE) {
             /* Inode nodes are sorted in descending size order */
             if (sa->len < sb->len) {
                 ubifs_err(c, "smaller inode node goes first");
                 goto error_dump;
             }
             continue;
         }
 
         /*
          * This is either a dentry or xentry, which should be sorted in
          * ascending (parent ino, hash) order.
          */
         inuma = key_inum(c, &sa->key);
         inumb = key_inum(c, &sb->key);
 
         if (inuma < inumb)
             continue;
         if (inuma > inumb) {
             ubifs_err(c, "larger inum %lu goes before inum %lu",
                   (unsigned long)inuma, (unsigned long)inumb);
             goto error_dump;
         }
 
         hasha = key_block(c, &sa->key);
         hashb = key_block(c, &sb->key);
 
         if (hasha > hashb) {
             ubifs_err(c, "larger hash %u goes before %u",
                   hasha, hashb);
             goto error_dump;
         }
     }
 
     return 0;
 
 error_dump:
     ubifs_msg(c, "dumping first node");
     ubifs_dump_node(c, sa->node, c->leb_size - sa->offs);
     ubifs_msg(c, "dumping second node");
     ubifs_dump_node(c, sb->node, c->leb_size - sb->offs);
     return -EINVAL;
 }
 
 static inline int chance(unsigned int n, unsigned int out_of)
 {
     return !!((prandom_u32() % out_of) + 1 <= n);
 
 }
 
 static int power_cut_emulated(struct ubifs_info *c, int lnum, int write)
 {
     struct ubifs_debug_info *d = c->dbg;
 
     ubifs_assert(c, dbg_is_tst_rcvry(c));
 
     if (!d->pc_cnt) {
         /* First call - decide delay to the power cut */
         if (chance(1, 2)) {
             unsigned long delay;
 
             if (chance(1, 2)) {
                 d->pc_delay = 1;
                 /* Fail within 1 minute */
                 delay = prandom_u32() % 60000;
                 d->pc_timeout = jiffies;
                 d->pc_timeout += msecs_to_jiffies(delay);
                 ubifs_warn(c, "failing after %lums", delay);
             } else {
                 d->pc_delay = 2;
                 delay = prandom_u32() % 10000;
                 /* Fail within 10000 operations */
                 d->pc_cnt_max = delay;
                 ubifs_warn(c, "failing after %lu calls", delay);
             }
         }
 
         d->pc_cnt += 1;
     }
 
     /* Determine if failure delay has expired */
     if (d->pc_delay == 1 && time_before(jiffies, d->pc_timeout))
             return 0;
     if (d->pc_delay == 2 && d->pc_cnt++ < d->pc_cnt_max)
             return 0;
 
     if (lnum == UBIFS_SB_LNUM) {
         if (write && chance(1, 2))
             return 0;
         if (chance(19, 20))
             return 0;
         ubifs_warn(c, "failing in super block LEB %d", lnum);
     } else if (lnum == UBIFS_MST_LNUM || lnum == UBIFS_MST_LNUM + 1) {
         if (chance(19, 20))
             return 0;
         ubifs_warn(c, "failing in master LEB %d", lnum);
     } else if (lnum >= UBIFS_LOG_LNUM && lnum <= c->log_last) {
         if (write && chance(99, 100))
             return 0;
         if (chance(399, 400))
             return 0;
         ubifs_warn(c, "failing in log LEB %d", lnum);
     } else if (lnum >= c->lpt_first && lnum <= c->lpt_last) {
         if (write && chance(7, 8))
             return 0;
         if (chance(19, 20))
             return 0;
         ubifs_warn(c, "failing in LPT LEB %d", lnum);
     } else if (lnum >= c->orph_first && lnum <= c->orph_last) {
         if (write && chance(1, 2))
             return 0;
         if (chance(9, 10))
             return 0;
         ubifs_warn(c, "failing in orphan LEB %d", lnum);
     } else if (lnum == c->ihead_lnum) {
         if (chance(99, 100))
             return 0;
         ubifs_warn(c, "failing in index head LEB %d", lnum);
     } else if (c->jheads && lnum == c->jheads[GCHD].wbuf.lnum) {
         if (chance(9, 10))
             return 0;
         ubifs_warn(c, "failing in GC head LEB %d", lnum);
     } else if (write && !RB_EMPTY_ROOT(&c->buds) &&
            !ubifs_search_bud(c, lnum)) {
         if (chance(19, 20))
             return 0;
         ubifs_warn(c, "failing in non-bud LEB %d", lnum);
     } else if (c->cmt_state == COMMIT_RUNNING_BACKGROUND ||
            c->cmt_state == COMMIT_RUNNING_REQUIRED) {
         if (chance(999, 1000))
             return 0;
         ubifs_warn(c, "failing in bud LEB %d commit running", lnum);
     } else {
         if (chance(9999, 10000))
             return 0;
         ubifs_warn(c, "failing in bud LEB %d commit not running", lnum);
     }
 
     d->pc_happened = 1;
     ubifs_warn(c, "========== Power cut emulated ==========");
     dump_stack();
     return 1;
 }
 
 static int corrupt_data(const struct ubifs_info *c, const void *buf,
             unsigned int len)
 {
     unsigned int from, to, ffs = chance(1, 2);
     unsigned char *p = (void *)buf;
 
     from = prandom_u32() % len;
     /* Corruption span max to end of write unit */
     to = min(len, ALIGN(from + 1, c->max_write_size));
 
     ubifs_warn(c, "filled bytes %u-%u with %s", from, to - 1,
            ffs ? "0xFFs" : "random data");
 
     if (ffs)
         memset(p + from, 0xFF, to - from);
     else
         prandom_bytes(p + from, to - from);
 
     return to;
 }
 
 int dbg_leb_write(struct ubifs_info *c, int lnum, const void *buf,
           int offs, int len)
 {
     int err, failing;
 
     if (dbg_is_power_cut(c))
         return -EROFS;
 
     failing = power_cut_emulated(c, lnum, 1);
     if (failing) {
         len = corrupt_data(c, buf, len);
         ubifs_warn(c, "actually write %d bytes to LEB %d:%d (the buffer was corrupted)",
                len, lnum, offs);
     }
     err = ubi_leb_write(c->ubi, lnum, buf, offs, len);
     if (err)
         return err;
     if (failing)
         return -EROFS;
     return 0;
 }
 
 int dbg_leb_change(struct ubifs_info *c, int lnum, const void *buf,
            int len)
 {
     int err;
 
     if (dbg_is_power_cut(c))
         return -EROFS;
     if (power_cut_emulated(c, lnum, 1))
         return -EROFS;
     err = ubi_leb_change(c->ubi, lnum, buf, len);
     if (err)
         return err;
     if (power_cut_emulated(c, lnum, 1))
         return -EROFS;
     return 0;
 }
 
 int dbg_leb_unmap(struct ubifs_info *c, int lnum)
 {
     int err;
 
     if (dbg_is_power_cut(c))
         return -EROFS;
     if (power_cut_emulated(c, lnum, 0))
         return -EROFS;
     err = ubi_leb_unmap(c->ubi, lnum);
     if (err)
         return err;
     if (power_cut_emulated(c, lnum, 0))
         return -EROFS;
     return 0;
 }
 
 int dbg_leb_map(struct ubifs_info *c, int lnum)
 {
     int err;
 
     if (dbg_is_power_cut(c))
         return -EROFS;
     if (power_cut_emulated(c, lnum, 0))
         return -EROFS;
     err = ubi_leb_map(c->ubi, lnum);
     if (err)
         return err;
     if (power_cut_emulated(c, lnum, 0))
         return -EROFS;
     return 0;
 }
 
 /*
  * Root directory for UBIFS stuff in debugfs. Contains sub-directories which
  * contain the stuff specific to particular file-system mounts.
  */
 static struct dentry *dfs_rootdir;
 
 static int dfs_file_open(struct inode *inode, struct file *file)
 {
     file->private_data = inode->i_private;
     return nonseekable_open(inode, file);
 }
 
 /**
  * provide_user_output - provide output to the user reading a debugfs file.
  * @val: boolean value for the answer
  * @u: the buffer to store the answer at
  * @count: size of the buffer
  * @ppos: position in the @u output buffer
  *
  * This is a simple helper function which stores @val boolean value in the user
  * buffer when the user reads one of UBIFS debugfs files. Returns amount of
  * bytes written to @u in case of success and a negative error code in case of
  * failure.
  */
 static int provide_user_output(int val, char __user *u, size_t count,
                    loff_t *ppos)
 {
     char buf[3];
 
     if (val)
         buf[0] = '1';
     else
         buf[0] = '0';
     buf[1] = '\n';
     buf[2] = 0x00;
 
     return simple_read_from_buffer(u, count, ppos, buf, 2);
 }
 
 static ssize_t dfs_file_read(struct file *file, char __user *u, size_t count,
                  loff_t *ppos)
 {
     struct dentry *dent = file->f_path.dentry;
     struct ubifs_info *c = file->private_data;
     struct ubifs_debug_info *d = c->dbg;
     int val;
 
     if (dent == d->dfs_chk_gen)
         val = d->chk_gen;
     else if (dent == d->dfs_chk_index)
         val = d->chk_index;
     else if (dent == d->dfs_chk_orph)
         val = d->chk_orph;
     else if (dent == d->dfs_chk_lprops)
         val = d->chk_lprops;
     else if (dent == d->dfs_chk_fs)
         val = d->chk_fs;
     else if (dent == d->dfs_tst_rcvry)
         val = d->tst_rcvry;
     else if (dent == d->dfs_ro_error)
         val = c->ro_error;
     else
         return -EINVAL;
 
     return provide_user_output(val, u, count, ppos);
 }
 
 /**
  * interpret_user_input - interpret user debugfs file input.
  * @u: user-provided buffer with the input
  * @count: buffer size
  *
  * This is a helper function which interpret user input to a boolean UBIFS
  * debugfs file. Returns %0 or %1 in case of success and a negative error code
  * in case of failure.
  */
 static int interpret_user_input(const char __user *u, size_t count)
 {
     size_t buf_size;
     char buf[8];
 
     buf_size = min_t(size_t, count, (sizeof(buf) - 1));
     if (copy_from_user(buf, u, buf_size))
         return -EFAULT;
 
     if (buf[0] == '1')
         return 1;
     else if (buf[0] == '0')
         return 0;
 
     return -EINVAL;
 }
 
 static ssize_t dfs_file_write(struct file *file, const char __user *u,
                   size_t count, loff_t *ppos)
 {
     struct ubifs_info *c = file->private_data;
     struct ubifs_debug_info *d = c->dbg;
     struct dentry *dent = file->f_path.dentry;
     int val;
 
     if (file->f_path.dentry == d->dfs_dump_lprops) {
         ubifs_dump_lprops(c);
         return count;
     }
     if (file->f_path.dentry == d->dfs_dump_budg) {
         ubifs_dump_budg(c, &c->bi);
         return count;
     }
     if (file->f_path.dentry == d->dfs_dump_tnc) {
         mutex_lock(&c->tnc_mutex);
         ubifs_dump_tnc(c);
         mutex_unlock(&c->tnc_mutex);
         return count;
     }
 
     val = interpret_user_input(u, count);
     if (val < 0)
         return val;
 
     if (dent == d->dfs_chk_gen)
         d->chk_gen = val;
     else if (dent == d->dfs_chk_index)
         d->chk_index = val;
     else if (dent == d->dfs_chk_orph)
         d->chk_orph = val;
     else if (dent == d->dfs_chk_lprops)
         d->chk_lprops = val;
     else if (dent == d->dfs_chk_fs)
         d->chk_fs = val;
     else if (dent == d->dfs_tst_rcvry)
         d->tst_rcvry = val;
     else if (dent == d->dfs_ro_error)
         c->ro_error = !!val;
     else
         return -EINVAL;
 
     return count;
 }
 
 static const struct file_operations dfs_fops = {
     .open = dfs_file_open,
     .read = dfs_file_read,
     .write = dfs_file_write,
     .owner = THIS_MODULE,
     .llseek = no_llseek,
 };
 
 /**
  * dbg_debugfs_init_fs - initialize debugfs for UBIFS instance.
  * @c: UBIFS file-system description object
  *
  * This function creates all debugfs files for this instance of UBIFS.
  *
  * Note, the only reason we have not merged this function with the
  * 'ubifs_debugging_init()' function is because it is better to initialize
  * debugfs interfaces at the very end of the mount process, and remove them at
  * the very beginning of the mount process.
  */
 void dbg_debugfs_init_fs(struct ubifs_info *c)
 {
     int n;
     const char *fname;
     struct ubifs_debug_info *d = c->dbg;
 
     n = snprintf(d->dfs_dir_name, UBIFS_DFS_DIR_LEN + 1, UBIFS_DFS_DIR_NAME,
              c->vi.ubi_num, c->vi.vol_id);
     if (n > UBIFS_DFS_DIR_LEN) {
         /* The array size is too small */
         return;
     }
 
     fname = d->dfs_dir_name;
     d->dfs_dir = debugfs_create_dir(fname, dfs_rootdir);
 
     fname = "dump_lprops";
     d->dfs_dump_lprops = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c,
                          &dfs_fops);
 
     fname = "dump_budg";
     d->dfs_dump_budg = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c,
                            &dfs_fops);
 
     fname = "dump_tnc";
     d->dfs_dump_tnc = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c,
                           &dfs_fops);
 
     fname = "chk_general";
     d->dfs_chk_gen = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                          d->dfs_dir, c, &dfs_fops);
 
     fname = "chk_index";
     d->dfs_chk_index = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                            d->dfs_dir, c, &dfs_fops);
 
     fname = "chk_orphans";
     d->dfs_chk_orph = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                           d->dfs_dir, c, &dfs_fops);
 
     fname = "chk_lprops";
     d->dfs_chk_lprops = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                         d->dfs_dir, c, &dfs_fops);
 
     fname = "chk_fs";
     d->dfs_chk_fs = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                         d->dfs_dir, c, &dfs_fops);
 
     fname = "tst_recovery";
     d->dfs_tst_rcvry = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                            d->dfs_dir, c, &dfs_fops);
 
     fname = "ro_error";
     d->dfs_ro_error = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                           d->dfs_dir, c, &dfs_fops);
 }
 
 /**
  * dbg_debugfs_exit_fs - remove all debugfs files.
  * @c: UBIFS file-system description object
  */
 void dbg_debugfs_exit_fs(struct ubifs_info *c)
 {
     debugfs_remove_recursive(c->dbg->dfs_dir);
 }
 
 struct ubifs_global_debug_info ubifs_dbg;
 
 static struct dentry *dfs_chk_gen;
 static struct dentry *dfs_chk_index;
 static struct dentry *dfs_chk_orph;
 static struct dentry *dfs_chk_lprops;
 static struct dentry *dfs_chk_fs;
 static struct dentry *dfs_tst_rcvry;
 
 static ssize_t dfs_global_file_read(struct file *file, char __user *u,
                     size_t count, loff_t *ppos)
 {
     struct dentry *dent = file->f_path.dentry;
     int val;
 
     if (dent == dfs_chk_gen)
         val = ubifs_dbg.chk_gen;
     else if (dent == dfs_chk_index)
         val = ubifs_dbg.chk_index;
     else if (dent == dfs_chk_orph)
         val = ubifs_dbg.chk_orph;
     else if (dent == dfs_chk_lprops)
         val = ubifs_dbg.chk_lprops;
     else if (dent == dfs_chk_fs)
         val = ubifs_dbg.chk_fs;
     else if (dent == dfs_tst_rcvry)
         val = ubifs_dbg.tst_rcvry;
     else
         return -EINVAL;
 
     return provide_user_output(val, u, count, ppos);
 }
 
 static ssize_t dfs_global_file_write(struct file *file, const char __user *u,
                      size_t count, loff_t *ppos)
 {
     struct dentry *dent = file->f_path.dentry;
     int val;
 
     val = interpret_user_input(u, count);
     if (val < 0)
         return val;
 
     if (dent == dfs_chk_gen)
         ubifs_dbg.chk_gen = val;
     else if (dent == dfs_chk_index)
         ubifs_dbg.chk_index = val;
     else if (dent == dfs_chk_orph)
         ubifs_dbg.chk_orph = val;
     else if (dent == dfs_chk_lprops)
         ubifs_dbg.chk_lprops = val;
     else if (dent == dfs_chk_fs)
         ubifs_dbg.chk_fs = val;
     else if (dent == dfs_tst_rcvry)
         ubifs_dbg.tst_rcvry = val;
     else
         return -EINVAL;
 
     return count;
 }
 
 static const struct file_operations dfs_global_fops = {
     .read = dfs_global_file_read,
     .write = dfs_global_file_write,
     .owner = THIS_MODULE,
     .llseek = no_llseek,
 };
 
 /**
  * dbg_debugfs_init - initialize debugfs file-system.
  *
  * UBIFS uses debugfs file-system to expose various debugging knobs to
  * user-space. This function creates "ubifs" directory in the debugfs
  * file-system.
  */
 void dbg_debugfs_init(void)
 {
     const char *fname;
 
     fname = "ubifs";
     dfs_rootdir = debugfs_create_dir(fname, NULL);
 
     fname = "chk_general";
     dfs_chk_gen = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir,
                       NULL, &dfs_global_fops);
 
     fname = "chk_index";
     dfs_chk_index = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                         dfs_rootdir, NULL, &dfs_global_fops);
 
     fname = "chk_orphans";
     dfs_chk_orph = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                        dfs_rootdir, NULL, &dfs_global_fops);
 
     fname = "chk_lprops";
     dfs_chk_lprops = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                          dfs_rootdir, NULL, &dfs_global_fops);
 
     fname = "chk_fs";
     dfs_chk_fs = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir,
                      NULL, &dfs_global_fops);
 
     fname = "tst_recovery";
     dfs_tst_rcvry = debugfs_create_file(fname, S_IRUSR | S_IWUSR,
                         dfs_rootdir, NULL, &dfs_global_fops);
 }
 
 /**
  * dbg_debugfs_exit - remove the "ubifs" directory from debugfs file-system.
  */
 void dbg_debugfs_exit(void)
 {
     debugfs_remove_recursive(dfs_rootdir);
 }
 
 void ubifs_assert_failed(struct ubifs_info *c, const char *expr,
              const char *file, int line)
 {
     ubifs_err(c, "UBIFS assert failed: %s, in %s:%u", expr, file, line);
 
     switch (c->assert_action) {
         case ASSACT_PANIC:
         BUG();
         break;
 
         case ASSACT_RO:
         ubifs_ro_mode(c, -EINVAL);
         break;
 
         case ASSACT_REPORT:
         default:
         dump_stack();
         break;
 
     }
 }
 
 /**
  * ubifs_debugging_init - initialize UBIFS debugging.
  * @c: UBIFS file-system description object
  *
  * This function initializes debugging-related data for the file system.
  * Returns zero in case of success and a negative error code in case of
  * failure.
  */
 int ubifs_debugging_init(struct ubifs_info *c)
 {
     c->dbg = kzalloc(sizeof(struct ubifs_debug_info), GFP_KERNEL);
     if (!c->dbg)
         return -ENOMEM;
 
     return 0;
 }
 
 /**
  * ubifs_debugging_exit - free debugging data.
  * @c: UBIFS file-system description object
  */
 void ubifs_debugging_exit(struct ubifs_info *c)
 {
     kfree(c->dbg);
 }