/*
   * This file is part of UBIFS.
   *
   * Copyright (C) 2006-2008 Nokia Corporation
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published by
   * the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
   *
   * 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(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";
  	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
  ", le32_to_cpu(ch->magic));
  	pr_err("\tcrc            %#x
  ", le32_to_cpu(ch->crc));
  	pr_err("\tnode_type      %d (%s)
  ", ch->node_type,

  	       dbg_ntype(ch->node_type));

  	pr_err("\tgroup_type     %d (%s)
  ", ch->group_type,

  	       dbg_gtype(ch->group_type));

  	pr_err("\tsqnum          %llu
  ",

  	       (unsigned long long)le64_to_cpu(ch->sqnum));

  	pr_err("\tlen            %u
  ", 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
  ", inode->i_ino);
  	pr_err("\tsize           %llu
  ",

  	       (unsigned long long)i_size_read(inode));

  	pr_err("\tnlink          %u
  ", inode->i_nlink);

  	pr_err("\tuid            %u
  ", (unsigned int)i_uid_read(inode));
  	pr_err("\tgid            %u
  ", (unsigned int)i_gid_read(inode));

  	pr_err("\tatime          %u.%u
  ",

  	       (unsigned int)inode->i_atime.tv_sec,
  	       (unsigned int)inode->i_atime.tv_nsec);

  	pr_err("\tmtime          %u.%u
  ",

  	       (unsigned int)inode->i_mtime.tv_sec,
  	       (unsigned int)inode->i_mtime.tv_nsec);

  	pr_err("\tctime          %u.%u
  ",

  	       (unsigned int)inode->i_ctime.tv_sec,
  	       (unsigned int)inode->i_ctime.tv_nsec);

  	pr_err("\tcreat_sqnum    %llu
  ", ui->creat_sqnum);
  	pr_err("\txattr_size     %u
  ", ui->xattr_size);
  	pr_err("\txattr_cnt      %u
  ", ui->xattr_cnt);
  	pr_err("\txattr_names    %u
  ", ui->xattr_names);
  	pr_err("\tdirty          %u
  ", ui->dirty);
  	pr_err("\txattr          %u
  ", ui->xattr);

  	pr_err("\tbulk_read      %u
  ", ui->bulk_read);

  	pr_err("\tsynced_i_size  %llu
  ",

  	       (unsigned long long)ui->synced_i_size);

  	pr_err("\tui_size        %llu
  ",

  	       (unsigned long long)ui->ui_size);

  	pr_err("\tflags          %d
  ", ui->flags);
  	pr_err("\tcompr_type     %d
  ", ui->compr_type);
  	pr_err("\tlast_page_read %lu
  ", ui->last_page_read);
  	pr_err("\tread_in_a_row  %lu
  ", ui->read_in_a_row);
  	pr_err("\tdata_len       %d
  ", ui->data_len);

  
  	if (!S_ISDIR(inode->i_mode))
  		return;

  	pr_err("List of directory entries:
  ");

  	ubifs_assert(!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
  ", PTR_ERR(dent));

  			break;
  		}

  		pr_err("\t%d: inode %llu, type %s, len %d
  ",
  		       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 i, n;
  	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;
  	}
  
  	spin_lock(&dbg_lock);
  	dump_ch(node);
  
  	switch (ch->node_type) {
  	case UBIFS_PAD_NODE:
  	{
  		const struct ubifs_pad_node *pad = node;

  		pr_err("\tpad_len        %u
  ", 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)
  ",

  		       (int)sup->key_hash, get_key_hash(sup->key_hash));

  		pr_err("\tkey_fmt        %d (%s)
  ",

  		       (int)sup->key_fmt, get_key_fmt(sup->key_fmt));

  		pr_err("\tflags          %#x
  ", sup_flags);

  		pr_err("\tbig_lpt        %u
  ",

  		       !!(sup_flags & UBIFS_FLG_BIGLPT));

  		pr_err("\tspace_fixup    %u
  ",

  		       !!(sup_flags & UBIFS_FLG_SPACE_FIXUP));

  		pr_err("\tmin_io_size    %u
  ", le32_to_cpu(sup->min_io_size));
  		pr_err("\tleb_size       %u
  ", le32_to_cpu(sup->leb_size));
  		pr_err("\tleb_cnt        %u
  ", le32_to_cpu(sup->leb_cnt));
  		pr_err("\tmax_leb_cnt    %u
  ", le32_to_cpu(sup->max_leb_cnt));
  		pr_err("\tmax_bud_bytes  %llu
  ",

  		       (unsigned long long)le64_to_cpu(sup->max_bud_bytes));

  		pr_err("\tlog_lebs       %u
  ", le32_to_cpu(sup->log_lebs));
  		pr_err("\tlpt_lebs       %u
  ", le32_to_cpu(sup->lpt_lebs));
  		pr_err("\torph_lebs      %u
  ", le32_to_cpu(sup->orph_lebs));
  		pr_err("\tjhead_cnt      %u
  ", le32_to_cpu(sup->jhead_cnt));
  		pr_err("\tfanout         %u
  ", le32_to_cpu(sup->fanout));
  		pr_err("\tlsave_cnt      %u
  ", le32_to_cpu(sup->lsave_cnt));
  		pr_err("\tdefault_compr  %u
  ",

  		       (int)le16_to_cpu(sup->default_compr));

  		pr_err("\trp_size        %llu
  ",

  		       (unsigned long long)le64_to_cpu(sup->rp_size));

  		pr_err("\trp_uid         %u
  ", le32_to_cpu(sup->rp_uid));
  		pr_err("\trp_gid         %u
  ", le32_to_cpu(sup->rp_gid));
  		pr_err("\tfmt_version    %u
  ", le32_to_cpu(sup->fmt_version));
  		pr_err("\ttime_gran      %u
  ", le32_to_cpu(sup->time_gran));
  		pr_err("\tUUID           %pUB
  ", sup->uuid);

  		break;
  	}
  	case UBIFS_MST_NODE:
  	{
  		const struct ubifs_mst_node *mst = node;

  		pr_err("\thighest_inum   %llu
  ",

  		       (unsigned long long)le64_to_cpu(mst->highest_inum));

  		pr_err("\tcommit number  %llu
  ",

  		       (unsigned long long)le64_to_cpu(mst->cmt_no));

  		pr_err("\tflags          %#x
  ", le32_to_cpu(mst->flags));
  		pr_err("\tlog_lnum       %u
  ", le32_to_cpu(mst->log_lnum));
  		pr_err("\troot_lnum      %u
  ", le32_to_cpu(mst->root_lnum));
  		pr_err("\troot_offs      %u
  ", le32_to_cpu(mst->root_offs));
  		pr_err("\troot_len       %u
  ", le32_to_cpu(mst->root_len));
  		pr_err("\tgc_lnum        %u
  ", le32_to_cpu(mst->gc_lnum));
  		pr_err("\tihead_lnum     %u
  ", le32_to_cpu(mst->ihead_lnum));
  		pr_err("\tihead_offs     %u
  ", le32_to_cpu(mst->ihead_offs));
  		pr_err("\tindex_size     %llu
  ",

  		       (unsigned long long)le64_to_cpu(mst->index_size));

  		pr_err("\tlpt_lnum       %u
  ", le32_to_cpu(mst->lpt_lnum));
  		pr_err("\tlpt_offs       %u
  ", le32_to_cpu(mst->lpt_offs));
  		pr_err("\tnhead_lnum     %u
  ", le32_to_cpu(mst->nhead_lnum));
  		pr_err("\tnhead_offs     %u
  ", le32_to_cpu(mst->nhead_offs));
  		pr_err("\tltab_lnum      %u
  ", le32_to_cpu(mst->ltab_lnum));
  		pr_err("\tltab_offs      %u
  ", le32_to_cpu(mst->ltab_offs));
  		pr_err("\tlsave_lnum     %u
  ", le32_to_cpu(mst->lsave_lnum));
  		pr_err("\tlsave_offs     %u
  ", le32_to_cpu(mst->lsave_offs));
  		pr_err("\tlscan_lnum     %u
  ", le32_to_cpu(mst->lscan_lnum));
  		pr_err("\tleb_cnt        %u
  ", le32_to_cpu(mst->leb_cnt));
  		pr_err("\tempty_lebs     %u
  ", le32_to_cpu(mst->empty_lebs));
  		pr_err("\tidx_lebs       %u
  ", le32_to_cpu(mst->idx_lebs));
  		pr_err("\ttotal_free     %llu
  ",

  		       (unsigned long long)le64_to_cpu(mst->total_free));

  		pr_err("\ttotal_dirty    %llu
  ",

  		       (unsigned long long)le64_to_cpu(mst->total_dirty));

  		pr_err("\ttotal_used     %llu
  ",

  		       (unsigned long long)le64_to_cpu(mst->total_used));

  		pr_err("\ttotal_dead     %llu
  ",

  		       (unsigned long long)le64_to_cpu(mst->total_dead));

  		pr_err("\ttotal_dark     %llu
  ",

  		       (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
  ", le32_to_cpu(ref->lnum));
  		pr_err("\toffs           %u
  ", le32_to_cpu(ref->offs));
  		pr_err("\tjhead          %u
  ", 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
  ",

  		       dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));

  		pr_err("\tcreat_sqnum    %llu
  ",

  		       (unsigned long long)le64_to_cpu(ino->creat_sqnum));

  		pr_err("\tsize           %llu
  ",

  		       (unsigned long long)le64_to_cpu(ino->size));

  		pr_err("\tnlink          %u
  ", le32_to_cpu(ino->nlink));
  		pr_err("\tatime          %lld.%u
  ",

  		       (long long)le64_to_cpu(ino->atime_sec),
  		       le32_to_cpu(ino->atime_nsec));

  		pr_err("\tmtime          %lld.%u
  ",

  		       (long long)le64_to_cpu(ino->mtime_sec),
  		       le32_to_cpu(ino->mtime_nsec));

  		pr_err("\tctime          %lld.%u
  ",

  		       (long long)le64_to_cpu(ino->ctime_sec),
  		       le32_to_cpu(ino->ctime_nsec));

  		pr_err("\tuid            %u
  ", le32_to_cpu(ino->uid));
  		pr_err("\tgid            %u
  ", le32_to_cpu(ino->gid));
  		pr_err("\tmode           %u
  ", le32_to_cpu(ino->mode));
  		pr_err("\tflags          %#x
  ", le32_to_cpu(ino->flags));
  		pr_err("\txattr_cnt      %u
  ", le32_to_cpu(ino->xattr_cnt));
  		pr_err("\txattr_size     %u
  ", le32_to_cpu(ino->xattr_size));
  		pr_err("\txattr_names    %u
  ", le32_to_cpu(ino->xattr_names));
  		pr_err("\tcompr_type     %#x
  ",

  		       (int)le16_to_cpu(ino->compr_type));

  		pr_err("\tdata len       %u
  ", 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
  ",

  		       dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));

  		pr_err("\tinum           %llu
  ",

  		       (unsigned long long)le64_to_cpu(dent->inum));

  		pr_err("\ttype           %d
  ", (int)dent->type);
  		pr_err("\tnlen           %d
  ", nlen);
  		pr_err("\tname           ");

  
  		if (nlen > UBIFS_MAX_NLEN)

  			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("
  ");

  
  		break;
  	}
  	case UBIFS_DATA_NODE:
  	{
  		const struct ubifs_data_node *dn = node;
  		int dlen = le32_to_cpu(ch->len) - UBIFS_DATA_NODE_SZ;
  
  		key_read(c, &dn->key, &key);

  		pr_err("\tkey            %s
  ",

  		       dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));

  		pr_err("\tsize           %u
  ", le32_to_cpu(dn->size));
  		pr_err("\tcompr_typ      %d
  ",

  		       (int)le16_to_cpu(dn->compr_type));

  		pr_err("\tdata size      %d
  ", dlen);
  		pr_err("\tdata:
  ");

  		print_hex_dump(KERN_ERR, "\t", DUMP_PREFIX_OFFSET, 32, 1,

  			       (void *)&dn->data, dlen, 0);
  		break;
  	}
  	case UBIFS_TRUN_NODE:
  	{
  		const struct ubifs_trun_node *trun = node;

  		pr_err("\tinum           %u
  ", le32_to_cpu(trun->inum));
  		pr_err("\told_size       %llu
  ",

  		       (unsigned long long)le64_to_cpu(trun->old_size));

  		pr_err("\tnew_size       %llu
  ",

  		       (unsigned long long)le64_to_cpu(trun->new_size));
  		break;
  	}
  	case UBIFS_IDX_NODE:
  	{
  		const struct ubifs_idx_node *idx = node;
  
  		n = le16_to_cpu(idx->child_cnt);

  		pr_err("\tchild_cnt      %d
  ", n);
  		pr_err("\tlevel          %d
  ", (int)le16_to_cpu(idx->level));
  		pr_err("\tBranches:
  ");

  
  		for (i = 0; i < n && i < c->fanout - 1; 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
  ",

  			       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
  ",

  		       (unsigned long long)
  				le64_to_cpu(orph->cmt_no) & LLONG_MAX);

  		pr_err("\tlast node flag %llu
  ",

  		       (unsigned long long)(le64_to_cpu(orph->cmt_no)) >> 63);
  		n = (le32_to_cpu(ch->len) - UBIFS_ORPH_NODE_SZ) >> 3;

  		pr_err("\t%d orphan inode numbers:
  ", n);

  		for (i = 0; i < n; i++)

  			pr_err("\t  ino %llu
  ",

  			       (unsigned long long)le64_to_cpu(orph->inos[i]));

  		break;
  	}
  	default:

  		pr_err("node type %d was not recognized
  ",

  		       (int)ch->node_type);
  	}
  	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
  ",

  	       req->new_ino, req->dirtied_ino);

  	pr_err("\tnew_ino_d   %d, dirtied_ino_d %d
  ",

  	       req->new_ino_d, req->dirtied_ino_d);

  	pr_err("\tnew_page    %d, dirtied_page %d
  ",

  	       req->new_page, req->dirtied_page);

  	pr_err("\tnew_dent    %d, mod_dent     %d
  ",

  	       req->new_dent, req->mod_dent);

  	pr_err("\tidx_growth  %d
  ", req->idx_growth);
  	pr_err("\tdata_growth %d dd_growth     %d
  ",

  	       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
  ",

  	       current->pid, lst->empty_lebs, lst->idx_lebs);

  	pr_err("\ttaken_empty_lebs %d, total_free %lld, total_dirty %lld
  ",

  	       lst->taken_empty_lebs, lst->total_free, lst->total_dirty);

  	pr_err("\ttotal_used %lld, total_dark %lld, total_dead %lld
  ",

  	       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
  ",

  	       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
  ",

  	       bi->data_growth, bi->dd_growth, bi->idx_growth);

  	pr_err("\tmin_idx_lebs %d, old_idx_sz %llu, uncommitted_idx %lld
  ",

  	       bi->min_idx_lebs, bi->old_idx_sz, bi->uncommitted_idx);

  	pr_err("\tpage_budget %d, inode_budget %d, dent_budget %d
  ",

  	       bi->page_budget, bi->inode_budget, bi->dent_budget);

  	pr_err("\tnospace %u, nospace_rp %u
  ", bi->nospace, bi->nospace_rp);
  	pr_err("\tdark_wm %d, dead_wm %d, max_idx_node_sz %d
  ",

  	       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
  ",

  	       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
  ",

  	       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
  ", 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
  ",

  			       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
  ", bud->lnum);

  	}
  	list_for_each_entry(bud, &c->old_buds, list)

  		pr_err("\told bud LEB %d
  ", bud->lnum);

  	list_for_each_entry(idx_gc, &c->idx_gc, list)

  		pr_err("\tGC'ed idx LEB %d unmap %d
  ",

  		       idx_gc->lnum, idx_gc->unmap);

  	pr_err("\tcommit state %d
  ", 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:
  ");
  	pr_err("\tavailable: %lld, outstanding %lld, free %lld
  ",

  	       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(")
  ");

  }

  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
  ", 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
  ", current->pid);

  }

  void ubifs_dump_lpt_info(struct ubifs_info *c)

  {
  	int i;
  
  	spin_lock(&dbg_lock);

  	pr_err("(pid %d) dumping LPT information
  ", current->pid);
  	pr_err("\tlpt_sz:        %lld
  ", c->lpt_sz);
  	pr_err("\tpnode_sz:      %d
  ", c->pnode_sz);
  	pr_err("\tnnode_sz:      %d
  ", c->nnode_sz);
  	pr_err("\tltab_sz:       %d
  ", c->ltab_sz);
  	pr_err("\tlsave_sz:      %d
  ", c->lsave_sz);
  	pr_err("\tbig_lpt:       %d
  ", c->big_lpt);
  	pr_err("\tlpt_hght:      %d
  ", c->lpt_hght);
  	pr_err("\tpnode_cnt:     %d
  ", c->pnode_cnt);
  	pr_err("\tnnode_cnt:     %d
  ", c->nnode_cnt);
  	pr_err("\tdirty_pn_cnt:  %d
  ", c->dirty_pn_cnt);
  	pr_err("\tdirty_nn_cnt:  %d
  ", c->dirty_nn_cnt);
  	pr_err("\tlsave_cnt:     %d
  ", c->lsave_cnt);
  	pr_err("\tspace_bits:    %d
  ", c->space_bits);
  	pr_err("\tlpt_lnum_bits: %d
  ", c->lpt_lnum_bits);
  	pr_err("\tlpt_offs_bits: %d
  ", c->lpt_offs_bits);
  	pr_err("\tlpt_spc_bits:  %d
  ", c->lpt_spc_bits);
  	pr_err("\tpcnt_bits:     %d
  ", c->pcnt_bits);
  	pr_err("\tlnum_bits:     %d
  ", c->lnum_bits);
  	pr_err("\tLPT root is at %d:%d
  ", c->lpt_lnum, c->lpt_offs);
  	pr_err("\tLPT head is at %d:%d
  ",

  	       c->nhead_lnum, c->nhead_offs);

  	pr_err("\tLPT ltab is at %d:%d
  ", c->ltab_lnum, c->ltab_offs);

  	if (c->big_lpt)

  		pr_err("\tLPT lsave is at %d:%d
  ",

  		       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
  ",

  		       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_sleb(const struct ubifs_info *c,
  		     const struct ubifs_scan_leb *sleb, int offs)

  {
  	struct ubifs_scan_node *snod;

  	pr_err("(pid %d) start dumping scanned data from LEB %d:%d
  ",

  	       current->pid, sleb->lnum, offs);
  
  	list_for_each_entry(snod, &sleb->nodes, list) {
  		cond_resched();

  		pr_err("Dumping node at LEB %d:%d len %d
  ",

  		       sleb->lnum, snod->offs, snod->len);

  		ubifs_dump_node(c, snod->node);

  	}
  }

  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
  ", current->pid, lnum);

  	buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);

  	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
  ", 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
  ", lnum,

  		       snod->offs, snod->len);

  		ubifs_dump_node(c, snod->node);

  	}

  	pr_err("(pid %d) finish dumping LEB %d
  ", 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
  ",

  	       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:
  ");

  	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, 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, 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)
  ",

  	       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
  ",

  		       i, lprops->lnum, lprops->hpos, lprops->free,
  		       lprops->dirty, lprops->flags);

  	}

  	pr_err("(pid %d) finish dumping heap
  ", 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:
  ", current->pid);
  	pr_err("\taddress %zx parent %zx cnext %zx
  ",

  	       (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);

  	pr_err("\tflags %lu iip %d level %d num %d
  ",

  	       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
  ",

  		       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("
  ");
  	pr_err("(pid %d) start dumping TNC tree
  ", current->pid);

  	znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
  	level = znode->level;

  	pr_err("== Level %d ==
  ", level);

  	while (znode) {
  		if (level != znode->level) {
  			level = znode->level;

  			pr_err("== Level %d ==
  ", level);

  		}

  		ubifs_dump_znode(c, znode);

  		znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
  	}

  	pr_err("(pid %d) finish dumping TNC tree
  ", 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 it 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;
  			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(!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);

  		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);

  		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
  ", zbr1->lnum, zbr1->offs);

  	ubifs_dump_node(c, dent1);

  	ubifs_msg(c, "second node at %d:%d
  ", zbr2->lnum, zbr2->offs);

  	ubifs_dump_node(c, dent2);

  
  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(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(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;
  			}
  			zbr->znode = child;
  		}
  
  		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(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(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);

  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);

  	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);

  			return -EINVAL;
  		}
  		if (sb->type != UBIFS_DATA_NODE) {

  			ubifs_err(c, "bad node type %d", sb->type);

  			ubifs_dump_node(c, sb->node);

  			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);
  	ubifs_dump_node(c, sb->node);

  	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);

  			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);

  			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);

  	ubifs_msg(c, "dumping second node");

  	ubifs_dump_node(c, sb->node);

  	return -EINVAL;
  	return 0;
  }

  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(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)