fs/yaffs2/yaffs_verify.c - manifest_repos/u-boot - Git at Google

 /*
  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
  * Copyright (C) 2002-2011 Aleph One Ltd.
  *   for Toby Churchill Ltd and Brightstar Engineering
  *
  * Created by Charles Manning <charles@aleph1.co.uk>
  *
  * 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.
  */

 #include "yaffs_verify.h"
 #include "yaffs_trace.h"
 #include "yaffs_bitmap.h"
 #include "yaffs_getblockinfo.h"
 #include "yaffs_nand.h"

 int yaffs_skip_verification(struct yaffs_dev *dev)
 {
 	return !(yaffs_trace_mask &
 		 (YAFFS_TRACE_VERIFY | YAFFS_TRACE_VERIFY_FULL));
 }

 static int yaffs_skip_full_verification(struct yaffs_dev *dev)
 {
 	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY_FULL));
 }

 static int yaffs_skip_nand_verification(struct yaffs_dev *dev)
 {
 	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY_NAND));
 }

 static const char * const block_state_name[] = {
 	"Unknown",
 	"Needs scan",
 	"Scanning",
 	"Empty",
 	"Allocating",
 	"Full",
 	"Dirty",
 	"Checkpoint",
 	"Collecting",
 	"Dead"
 };

 void yaffs_verify_blk(struct yaffs_dev *dev, struct yaffs_block_info *bi, int n)
 {
 	int actually_used;
 	int in_use;

 	if (yaffs_skip_verification(dev))
 		return;

 	/* Report illegal runtime states */
 	if (bi->block_state >= YAFFS_NUMBER_OF_BLOCK_STATES)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Block %d has undefined state %d",
 			n, bi->block_state);

 	switch (bi->block_state) {
 	case YAFFS_BLOCK_STATE_UNKNOWN:
 	case YAFFS_BLOCK_STATE_SCANNING:
 	case YAFFS_BLOCK_STATE_NEEDS_SCAN:
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Block %d has bad run-state %s",
 			n, block_state_name[bi->block_state]);
 	}

 	/* Check pages in use and soft deletions are legal */

 	actually_used = bi->pages_in_use - bi->soft_del_pages;

 	if (bi->pages_in_use < 0 ||
 	    bi->pages_in_use > dev->param.chunks_per_block ||
 	    bi->soft_del_pages < 0 ||
 	    bi->soft_del_pages > dev->param.chunks_per_block ||
 	    actually_used < 0 || actually_used > dev->param.chunks_per_block)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Block %d has illegal values pages_in_used %d soft_del_pages %d",
 			n, bi->pages_in_use, bi->soft_del_pages);

 	/* Check chunk bitmap legal */
 	in_use = yaffs_count_chunk_bits(dev, n);
 	if (in_use != bi->pages_in_use)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Block %d has inconsistent values pages_in_use %d counted chunk bits %d",
 			n, bi->pages_in_use, in_use);
 }

 void yaffs_verify_collected_blk(struct yaffs_dev *dev,
 				struct yaffs_block_info *bi, int n)
 {
 	yaffs_verify_blk(dev, bi, n);

 	/* After collection the block should be in the erased state */

 	if (bi->block_state != YAFFS_BLOCK_STATE_COLLECTING &&
 	    bi->block_state != YAFFS_BLOCK_STATE_EMPTY) {
 		yaffs_trace(YAFFS_TRACE_ERROR,
 			"Block %d is in state %d after gc, should be erased",
 			n, bi->block_state);
 	}
 }

 void yaffs_verify_blocks(struct yaffs_dev *dev)
 {
 	int i;
 	int state_count[YAFFS_NUMBER_OF_BLOCK_STATES];
 	int illegal_states = 0;

 	if (yaffs_skip_verification(dev))
 		return;

 	memset(state_count, 0, sizeof(state_count));

 	for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
 		struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
 		yaffs_verify_blk(dev, bi, i);

 		if (bi->block_state < YAFFS_NUMBER_OF_BLOCK_STATES)
 			state_count[bi->block_state]++;
 		else
 			illegal_states++;
 	}

 	yaffs_trace(YAFFS_TRACE_VERIFY,	"Block summary");

 	yaffs_trace(YAFFS_TRACE_VERIFY,
 		"%d blocks have illegal states",
 		illegal_states);
 	if (state_count[YAFFS_BLOCK_STATE_ALLOCATING] > 1)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Too many allocating blocks");

 	for (i = 0; i < YAFFS_NUMBER_OF_BLOCK_STATES; i++)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"%s %d blocks",
 			block_state_name[i], state_count[i]);

 	if (dev->blocks_in_checkpt != state_count[YAFFS_BLOCK_STATE_CHECKPOINT])
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Checkpoint block count wrong dev %d count %d",
 			dev->blocks_in_checkpt,
 			state_count[YAFFS_BLOCK_STATE_CHECKPOINT]);

 	if (dev->n_erased_blocks != state_count[YAFFS_BLOCK_STATE_EMPTY])
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Erased block count wrong dev %d count %d",
 			dev->n_erased_blocks,
 			state_count[YAFFS_BLOCK_STATE_EMPTY]);

 	if (state_count[YAFFS_BLOCK_STATE_COLLECTING] > 1)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Too many collecting blocks %d (max is 1)",
 			state_count[YAFFS_BLOCK_STATE_COLLECTING]);
 }

 /*
  * Verify the object header. oh must be valid, but obj and tags may be NULL in
  * which case those tests will not be performed.
  */
 void yaffs_verify_oh(struct yaffs_obj *obj, struct yaffs_obj_hdr *oh,
 		     struct yaffs_ext_tags *tags, int parent_check)
 {
 	if (obj && yaffs_skip_verification(obj->my_dev))
 		return;

 	if (!(tags && obj && oh)) {
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Verifying object header tags %p obj %p oh %p",
 			tags, obj, oh);
 		return;
 	}

 	if (oh->type <= YAFFS_OBJECT_TYPE_UNKNOWN ||
 	    oh->type > YAFFS_OBJECT_TYPE_MAX)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d header type is illegal value 0x%x",
 			tags->obj_id, oh->type);

 	if (tags->obj_id != obj->obj_id)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d header mismatch obj_id %d",
 			tags->obj_id, obj->obj_id);

 	/*
 	 * Check that the object's parent ids match if parent_check requested.
 	 *
 	 * Tests do not apply to the root object.
 	 */

 	if (parent_check && tags->obj_id > 1 && !obj->parent)
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d header mismatch parent_id %d obj->parent is NULL",
 			tags->obj_id, oh->parent_obj_id);

 	if (parent_check && obj->parent &&
 	    oh->parent_obj_id != obj->parent->obj_id &&
 	    (oh->parent_obj_id != YAFFS_OBJECTID_UNLINKED ||
 	     obj->parent->obj_id != YAFFS_OBJECTID_DELETED))
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d header mismatch parent_id %d parent_obj_id %d",
 			tags->obj_id, oh->parent_obj_id,
 			obj->parent->obj_id);

 	if (tags->obj_id > 1 && oh->name[0] == 0)	/* Null name */
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d header name is NULL",
 			obj->obj_id);

 	if (tags->obj_id > 1 && ((u8) (oh->name[0])) == 0xff)	/* Junk name */
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d header name is 0xff",
 			obj->obj_id);
 }

 void yaffs_verify_file(struct yaffs_obj *obj)
 {
 	u32 x;
 	int required_depth;
 	int last_chunk;
 	u32 offset_in_chunk;
 	u32 the_chunk;

 	u32 i;
 	struct yaffs_dev *dev;
 	struct yaffs_ext_tags tags;
 	struct yaffs_tnode *tn;
 	u32 obj_id;

 	if (!obj)
 		return;

 	if (yaffs_skip_verification(obj->my_dev))
 		return;

 	dev = obj->my_dev;
 	obj_id = obj->obj_id;


 	/* Check file size is consistent with tnode depth */
 	yaffs_addr_to_chunk(dev, obj->variant.file_variant.file_size,
 				&last_chunk, &offset_in_chunk);
 	last_chunk++;
 	x = last_chunk >> YAFFS_TNODES_LEVEL0_BITS;
 	required_depth = 0;
 	while (x > 0) {
 		x >>= YAFFS_TNODES_INTERNAL_BITS;
 		required_depth++;
 	}

 	/* Check that the chunks in the tnode tree are all correct.
 	 * We do this by scanning through the tnode tree and
 	 * checking the tags for every chunk match.
 	 */

 	if (yaffs_skip_nand_verification(dev))
 		return;

 	for (i = 1; i <= last_chunk; i++) {
 		tn = yaffs_find_tnode_0(dev, &obj->variant.file_variant, i);

 		if (!tn)
 			continue;

 		the_chunk = yaffs_get_group_base(dev, tn, i);
 		if (the_chunk > 0) {
 			yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL,
 						 &tags);
 			if (tags.obj_id != obj_id || tags.chunk_id != i)
 				yaffs_trace(YAFFS_TRACE_VERIFY,
 					"Object %d chunk_id %d NAND mismatch chunk %d tags (%d:%d)",
 					obj_id, i, the_chunk,
 					tags.obj_id, tags.chunk_id);
 		}
 	}
 }

 void yaffs_verify_link(struct yaffs_obj *obj)
 {
 	if (obj && yaffs_skip_verification(obj->my_dev))
 		return;

 	/* Verify sane equivalent object */
 }

 void yaffs_verify_symlink(struct yaffs_obj *obj)
 {
 	if (obj && yaffs_skip_verification(obj->my_dev))
 		return;

 	/* Verify symlink string */
 }

 void yaffs_verify_special(struct yaffs_obj *obj)
 {
 	if (obj && yaffs_skip_verification(obj->my_dev))
 		return;
 }

 void yaffs_verify_obj(struct yaffs_obj *obj)
 {
 	struct yaffs_dev *dev;
 	u32 chunk_min;
 	u32 chunk_max;
 	u32 chunk_id_ok;
 	u32 chunk_in_range;
 	u32 chunk_wrongly_deleted;
 	u32 chunk_valid;

 	if (!obj)
 		return;

 	if (obj->being_created)
 		return;

 	dev = obj->my_dev;

 	if (yaffs_skip_verification(dev))
 		return;

 	/* Check sane object header chunk */

 	chunk_min = dev->internal_start_block * dev->param.chunks_per_block;
 	chunk_max =
 	    (dev->internal_end_block + 1) * dev->param.chunks_per_block - 1;

 	chunk_in_range = (((unsigned)(obj->hdr_chunk)) >= chunk_min &&
 			  ((unsigned)(obj->hdr_chunk)) <= chunk_max);
 	chunk_id_ok = chunk_in_range || (obj->hdr_chunk == 0);
 	chunk_valid = chunk_in_range &&
 	    yaffs_check_chunk_bit(dev,
 				  obj->hdr_chunk / dev->param.chunks_per_block,
 				  obj->hdr_chunk % dev->param.chunks_per_block);
 	chunk_wrongly_deleted = chunk_in_range && !chunk_valid;

 	if (!obj->fake && (!chunk_id_ok || chunk_wrongly_deleted))
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d has chunk_id %d %s %s",
 			obj->obj_id, obj->hdr_chunk,
 			chunk_id_ok ? "" : ",out of range",
 			chunk_wrongly_deleted ? ",marked as deleted" : "");

 	if (chunk_valid && !yaffs_skip_nand_verification(dev)) {
 		struct yaffs_ext_tags tags;
 		struct yaffs_obj_hdr *oh;
 		u8 *buffer = yaffs_get_temp_buffer(dev);

 		oh = (struct yaffs_obj_hdr *)buffer;

 		yaffs_rd_chunk_tags_nand(dev, obj->hdr_chunk, buffer, &tags);

 		yaffs_verify_oh(obj, oh, &tags, 1);

 		yaffs_release_temp_buffer(dev, buffer);
 	}

 	/* Verify it has a parent */
 	if (obj && !obj->fake && (!obj->parent || obj->parent->my_dev != dev)) {
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d has parent pointer %p which does not look like an object",
 			obj->obj_id, obj->parent);
 	}

 	/* Verify parent is a directory */
 	if (obj->parent &&
 	    obj->parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d's parent is not a directory (type %d)",
 			obj->obj_id, obj->parent->variant_type);
 	}

 	switch (obj->variant_type) {
 	case YAFFS_OBJECT_TYPE_FILE:
 		yaffs_verify_file(obj);
 		break;
 	case YAFFS_OBJECT_TYPE_SYMLINK:
 		yaffs_verify_symlink(obj);
 		break;
 	case YAFFS_OBJECT_TYPE_DIRECTORY:
 		yaffs_verify_dir(obj);
 		break;
 	case YAFFS_OBJECT_TYPE_HARDLINK:
 		yaffs_verify_link(obj);
 		break;
 	case YAFFS_OBJECT_TYPE_SPECIAL:
 		yaffs_verify_special(obj);
 		break;
 	case YAFFS_OBJECT_TYPE_UNKNOWN:
 	default:
 		yaffs_trace(YAFFS_TRACE_VERIFY,
 			"Obj %d has illegaltype %d",
 		   obj->obj_id, obj->variant_type);
 		break;
 	}
 }

 void yaffs_verify_objects(struct yaffs_dev *dev)
 {
 	struct yaffs_obj *obj;
 	int i;
 	struct list_head *lh;

 	if (yaffs_skip_verification(dev))
 		return;

 	/* Iterate through the objects in each hash entry */

 	for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
 		list_for_each(lh, &dev->obj_bucket[i].list) {
 			obj = list_entry(lh, struct yaffs_obj, hash_link);
 			yaffs_verify_obj(obj);
 		}
 	}
 }

 void yaffs_verify_obj_in_dir(struct yaffs_obj *obj)
 {
 	struct list_head *lh;
 	struct yaffs_obj *list_obj;
 	int count = 0;

 	if (!obj) {
 		yaffs_trace(YAFFS_TRACE_ALWAYS, "No object to verify");
 		BUG();
 		return;
 	}

 	if (yaffs_skip_verification(obj->my_dev))
 		return;

 	if (!obj->parent) {
 		yaffs_trace(YAFFS_TRACE_ALWAYS, "Object does not have parent");
 		BUG();
 		return;
 	}

 	if (obj->parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
 		yaffs_trace(YAFFS_TRACE_ALWAYS, "Parent is not directory");
 		BUG();
 	}

 	/* Iterate through the objects in each hash entry */

 	list_for_each(lh, &obj->parent->variant.dir_variant.children) {
 		list_obj = list_entry(lh, struct yaffs_obj, siblings);
 		yaffs_verify_obj(list_obj);
 		if (obj == list_obj)
 			count++;
 	}

 	if (count != 1) {
 		yaffs_trace(YAFFS_TRACE_ALWAYS,
 			"Object in directory %d times",
 			count);
 		BUG();
 	}
 }

 void yaffs_verify_dir(struct yaffs_obj *directory)
 {
 	struct list_head *lh;
 	struct yaffs_obj *list_obj;

 	if (!directory) {
 		BUG();
 		return;
 	}

 	if (yaffs_skip_full_verification(directory->my_dev))
 		return;

 	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
 		yaffs_trace(YAFFS_TRACE_ALWAYS,
 			"Directory has wrong type: %d",
 			directory->variant_type);
 		BUG();
 	}

 	/* Iterate through the objects in each hash entry */

 	list_for_each(lh, &directory->variant.dir_variant.children) {
 		list_obj = list_entry(lh, struct yaffs_obj, siblings);
 		if (list_obj->parent != directory) {
 			yaffs_trace(YAFFS_TRACE_ALWAYS,
 				"Object in directory list has wrong parent %p",
 				list_obj->parent);
 			BUG();
 		}
 		yaffs_verify_obj_in_dir(list_obj);
 	}
 }

 static int yaffs_free_verification_failures;

 void yaffs_verify_free_chunks(struct yaffs_dev *dev)
 {
 	int counted;
 	int difference;

 	if (yaffs_skip_verification(dev))
 		return;

 	counted = yaffs_count_free_chunks(dev);

 	difference = dev->n_free_chunks - counted;

 	if (difference) {
 		yaffs_trace(YAFFS_TRACE_ALWAYS,
 			"Freechunks verification failure %d %d %d",
 			dev->n_free_chunks, counted, difference);
 		yaffs_free_verification_failures++;
 	}
 }

 int yaffs_verify_file_sane(struct yaffs_obj *in)
 {
 	return YAFFS_OK;
 }
	/*
	* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
	*
	* Copyright (C) 2002-2011 Aleph One Ltd.
	* for Toby Churchill Ltd and Brightstar Engineering
	*
	* Created by Charles Manning <charles@aleph1.co.uk>
	*
	* 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.
	*/

	#include "yaffs_verify.h"
	#include "yaffs_trace.h"
	#include "yaffs_bitmap.h"
	#include "yaffs_getblockinfo.h"
	#include "yaffs_nand.h"

	int yaffs_skip_verification(struct yaffs_dev *dev)
	{
	return !(yaffs_trace_mask &
	(YAFFS_TRACE_VERIFY \| YAFFS_TRACE_VERIFY_FULL));
	}

	static int yaffs_skip_full_verification(struct yaffs_dev *dev)
	{
	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY_FULL));
	}

	static int yaffs_skip_nand_verification(struct yaffs_dev *dev)
	{
	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY_NAND));
	}

	static const char * const block_state_name[] = {
	"Unknown",
	"Needs scan",
	"Scanning",
	"Empty",
	"Allocating",
	"Full",
	"Dirty",
	"Checkpoint",
	"Collecting",
	"Dead"
	};

	void yaffs_verify_blk(struct yaffs_dev dev, struct yaffs_block_info bi, int n)
	{
	int actually_used;
	int in_use;

	if (yaffs_skip_verification(dev))
	return;

	/* Report illegal runtime states */
	if (bi->block_state >= YAFFS_NUMBER_OF_BLOCK_STATES)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Block %d has undefined state %d",
	n, bi->block_state);

	switch (bi->block_state) {
	case YAFFS_BLOCK_STATE_UNKNOWN:
	case YAFFS_BLOCK_STATE_SCANNING:
	case YAFFS_BLOCK_STATE_NEEDS_SCAN:
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Block %d has bad run-state %s",
	n, block_state_name[bi->block_state]);
	}

	/* Check pages in use and soft deletions are legal */

	actually_used = bi->pages_in_use - bi->soft_del_pages;

	if (bi->pages_in_use < 0 \|\|
	bi->pages_in_use > dev->param.chunks_per_block \|\|
	bi->soft_del_pages < 0 \|\|
	bi->soft_del_pages > dev->param.chunks_per_block \|\|
	actually_used < 0 \|\| actually_used > dev->param.chunks_per_block)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Block %d has illegal values pages_in_used %d soft_del_pages %d",
	n, bi->pages_in_use, bi->soft_del_pages);

	/* Check chunk bitmap legal */
	in_use = yaffs_count_chunk_bits(dev, n);
	if (in_use != bi->pages_in_use)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Block %d has inconsistent values pages_in_use %d counted chunk bits %d",
	n, bi->pages_in_use, in_use);
	}

	void yaffs_verify_collected_blk(struct yaffs_dev *dev,
	struct yaffs_block_info *bi, int n)
	{
	yaffs_verify_blk(dev, bi, n);

	/* After collection the block should be in the erased state */

	if (bi->block_state != YAFFS_BLOCK_STATE_COLLECTING &&
	bi->block_state != YAFFS_BLOCK_STATE_EMPTY) {
	yaffs_trace(YAFFS_TRACE_ERROR,
	"Block %d is in state %d after gc, should be erased",
	n, bi->block_state);
	}
	}

	void yaffs_verify_blocks(struct yaffs_dev *dev)
	{
	int i;
	int state_count[YAFFS_NUMBER_OF_BLOCK_STATES];
	int illegal_states = 0;

	if (yaffs_skip_verification(dev))
	return;

	memset(state_count, 0, sizeof(state_count));

	for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
	struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
	yaffs_verify_blk(dev, bi, i);

	if (bi->block_state < YAFFS_NUMBER_OF_BLOCK_STATES)
	state_count[bi->block_state]++;
	else
	illegal_states++;
	}

	yaffs_trace(YAFFS_TRACE_VERIFY, "Block summary");

	yaffs_trace(YAFFS_TRACE_VERIFY,
	"%d blocks have illegal states",
	illegal_states);
	if (state_count[YAFFS_BLOCK_STATE_ALLOCATING] > 1)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Too many allocating blocks");

	for (i = 0; i < YAFFS_NUMBER_OF_BLOCK_STATES; i++)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"%s %d blocks",
	block_state_name[i], state_count[i]);

	if (dev->blocks_in_checkpt != state_count[YAFFS_BLOCK_STATE_CHECKPOINT])
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Checkpoint block count wrong dev %d count %d",
	dev->blocks_in_checkpt,
	state_count[YAFFS_BLOCK_STATE_CHECKPOINT]);

	if (dev->n_erased_blocks != state_count[YAFFS_BLOCK_STATE_EMPTY])
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Erased block count wrong dev %d count %d",
	dev->n_erased_blocks,
	state_count[YAFFS_BLOCK_STATE_EMPTY]);

	if (state_count[YAFFS_BLOCK_STATE_COLLECTING] > 1)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Too many collecting blocks %d (max is 1)",
	state_count[YAFFS_BLOCK_STATE_COLLECTING]);
	}

	/*
	* Verify the object header. oh must be valid, but obj and tags may be NULL in
	* which case those tests will not be performed.
	*/
	void yaffs_verify_oh(struct yaffs_obj obj, struct yaffs_obj_hdr oh,
	struct yaffs_ext_tags *tags, int parent_check)
	{
	if (obj && yaffs_skip_verification(obj->my_dev))
	return;

	if (!(tags && obj && oh)) {
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Verifying object header tags %p obj %p oh %p",
	tags, obj, oh);
	return;
	}

	if (oh->type <= YAFFS_OBJECT_TYPE_UNKNOWN \|\|
	oh->type > YAFFS_OBJECT_TYPE_MAX)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d header type is illegal value 0x%x",
	tags->obj_id, oh->type);

	if (tags->obj_id != obj->obj_id)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d header mismatch obj_id %d",
	tags->obj_id, obj->obj_id);

	/*
	* Check that the object's parent ids match if parent_check requested.
	*
	* Tests do not apply to the root object.
	*/

	if (parent_check && tags->obj_id > 1 && !obj->parent)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d header mismatch parent_id %d obj->parent is NULL",
	tags->obj_id, oh->parent_obj_id);

	if (parent_check && obj->parent &&
	oh->parent_obj_id != obj->parent->obj_id &&
	(oh->parent_obj_id != YAFFS_OBJECTID_UNLINKED \|\|
	obj->parent->obj_id != YAFFS_OBJECTID_DELETED))
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d header mismatch parent_id %d parent_obj_id %d",
	tags->obj_id, oh->parent_obj_id,
	obj->parent->obj_id);

	if (tags->obj_id > 1 && oh->name[0] == 0) /* Null name */
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d header name is NULL",
	obj->obj_id);

	if (tags->obj_id > 1 && ((u8) (oh->name[0])) == 0xff) /* Junk name */
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d header name is 0xff",
	obj->obj_id);
	}

	void yaffs_verify_file(struct yaffs_obj *obj)
	{
	u32 x;
	int required_depth;
	int last_chunk;
	u32 offset_in_chunk;
	u32 the_chunk;

	u32 i;
	struct yaffs_dev *dev;
	struct yaffs_ext_tags tags;
	struct yaffs_tnode *tn;
	u32 obj_id;

	if (!obj)
	return;

	if (yaffs_skip_verification(obj->my_dev))
	return;

	dev = obj->my_dev;
	obj_id = obj->obj_id;


	/* Check file size is consistent with tnode depth */
	yaffs_addr_to_chunk(dev, obj->variant.file_variant.file_size,
	&last_chunk, &offset_in_chunk);
	last_chunk++;
	x = last_chunk >> YAFFS_TNODES_LEVEL0_BITS;
	required_depth = 0;
	while (x > 0) {
	x >>= YAFFS_TNODES_INTERNAL_BITS;
	required_depth++;
	}

	/* Check that the chunks in the tnode tree are all correct.
	* We do this by scanning through the tnode tree and
	* checking the tags for every chunk match.
	*/

	if (yaffs_skip_nand_verification(dev))
	return;

	for (i = 1; i <= last_chunk; i++) {
	tn = yaffs_find_tnode_0(dev, &obj->variant.file_variant, i);

	if (!tn)
	continue;

	the_chunk = yaffs_get_group_base(dev, tn, i);
	if (the_chunk > 0) {
	yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL,
	&tags);
	if (tags.obj_id != obj_id \|\| tags.chunk_id != i)
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Object %d chunk_id %d NAND mismatch chunk %d tags (%d:%d)",
	obj_id, i, the_chunk,
	tags.obj_id, tags.chunk_id);
	}
	}
	}

	void yaffs_verify_link(struct yaffs_obj *obj)
	{
	if (obj && yaffs_skip_verification(obj->my_dev))
	return;

	/* Verify sane equivalent object */
	}

	void yaffs_verify_symlink(struct yaffs_obj *obj)
	{
	if (obj && yaffs_skip_verification(obj->my_dev))
	return;

	/* Verify symlink string */
	}

	void yaffs_verify_special(struct yaffs_obj *obj)
	{
	if (obj && yaffs_skip_verification(obj->my_dev))
	return;
	}

	void yaffs_verify_obj(struct yaffs_obj *obj)
	{
	struct yaffs_dev *dev;
	u32 chunk_min;
	u32 chunk_max;
	u32 chunk_id_ok;
	u32 chunk_in_range;
	u32 chunk_wrongly_deleted;
	u32 chunk_valid;

	if (!obj)
	return;

	if (obj->being_created)
	return;

	dev = obj->my_dev;

	if (yaffs_skip_verification(dev))
	return;

	/* Check sane object header chunk */

	chunk_min = dev->internal_start_block * dev->param.chunks_per_block;
	chunk_max =
	(dev->internal_end_block + 1) * dev->param.chunks_per_block - 1;

	chunk_in_range = (((unsigned)(obj->hdr_chunk)) >= chunk_min &&
	((unsigned)(obj->hdr_chunk)) <= chunk_max);
	chunk_id_ok = chunk_in_range \|\| (obj->hdr_chunk == 0);
	chunk_valid = chunk_in_range &&
	yaffs_check_chunk_bit(dev,
	obj->hdr_chunk / dev->param.chunks_per_block,
	obj->hdr_chunk % dev->param.chunks_per_block);
	chunk_wrongly_deleted = chunk_in_range && !chunk_valid;

	if (!obj->fake && (!chunk_id_ok \|\| chunk_wrongly_deleted))
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d has chunk_id %d %s %s",
	obj->obj_id, obj->hdr_chunk,
	chunk_id_ok ? "" : ",out of range",
	chunk_wrongly_deleted ? ",marked as deleted" : "");

	if (chunk_valid && !yaffs_skip_nand_verification(dev)) {
	struct yaffs_ext_tags tags;
	struct yaffs_obj_hdr *oh;
	u8 *buffer = yaffs_get_temp_buffer(dev);

	oh = (struct yaffs_obj_hdr *)buffer;

	yaffs_rd_chunk_tags_nand(dev, obj->hdr_chunk, buffer, &tags);

	yaffs_verify_oh(obj, oh, &tags, 1);

	yaffs_release_temp_buffer(dev, buffer);
	}

	/* Verify it has a parent */
	if (obj && !obj->fake && (!obj->parent \|\| obj->parent->my_dev != dev)) {
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d has parent pointer %p which does not look like an object",
	obj->obj_id, obj->parent);
	}

	/* Verify parent is a directory */
	if (obj->parent &&
	obj->parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d's parent is not a directory (type %d)",
	obj->obj_id, obj->parent->variant_type);
	}

	switch (obj->variant_type) {
	case YAFFS_OBJECT_TYPE_FILE:
	yaffs_verify_file(obj);
	break;
	case YAFFS_OBJECT_TYPE_SYMLINK:
	yaffs_verify_symlink(obj);
	break;
	case YAFFS_OBJECT_TYPE_DIRECTORY:
	yaffs_verify_dir(obj);
	break;
	case YAFFS_OBJECT_TYPE_HARDLINK:
	yaffs_verify_link(obj);
	break;
	case YAFFS_OBJECT_TYPE_SPECIAL:
	yaffs_verify_special(obj);
	break;
	case YAFFS_OBJECT_TYPE_UNKNOWN:
	default:
	yaffs_trace(YAFFS_TRACE_VERIFY,
	"Obj %d has illegaltype %d",
	obj->obj_id, obj->variant_type);
	break;
	}
	}

	void yaffs_verify_objects(struct yaffs_dev *dev)
	{
	struct yaffs_obj *obj;
	int i;
	struct list_head *lh;

	if (yaffs_skip_verification(dev))
	return;

	/* Iterate through the objects in each hash entry */

	for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
	list_for_each(lh, &dev->obj_bucket[i].list) {
	obj = list_entry(lh, struct yaffs_obj, hash_link);
	yaffs_verify_obj(obj);
	}
	}
	}

	void yaffs_verify_obj_in_dir(struct yaffs_obj *obj)
	{
	struct list_head *lh;
	struct yaffs_obj *list_obj;
	int count = 0;

	if (!obj) {
	yaffs_trace(YAFFS_TRACE_ALWAYS, "No object to verify");
	BUG();
	return;
	}

	if (yaffs_skip_verification(obj->my_dev))
	return;

	if (!obj->parent) {
	yaffs_trace(YAFFS_TRACE_ALWAYS, "Object does not have parent");
	BUG();
	return;
	}

	if (obj->parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
	yaffs_trace(YAFFS_TRACE_ALWAYS, "Parent is not directory");
	BUG();
	}

	/* Iterate through the objects in each hash entry */

	list_for_each(lh, &obj->parent->variant.dir_variant.children) {
	list_obj = list_entry(lh, struct yaffs_obj, siblings);
	yaffs_verify_obj(list_obj);
	if (obj == list_obj)
	count++;
	}

	if (count != 1) {
	yaffs_trace(YAFFS_TRACE_ALWAYS,
	"Object in directory %d times",
	count);
	BUG();
	}
	}

	void yaffs_verify_dir(struct yaffs_obj *directory)
	{
	struct list_head *lh;
	struct yaffs_obj *list_obj;

	if (!directory) {
	BUG();
	return;
	}

	if (yaffs_skip_full_verification(directory->my_dev))
	return;

	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
	yaffs_trace(YAFFS_TRACE_ALWAYS,
	"Directory has wrong type: %d",
	directory->variant_type);
	BUG();
	}

	/* Iterate through the objects in each hash entry */

	list_for_each(lh, &directory->variant.dir_variant.children) {
	list_obj = list_entry(lh, struct yaffs_obj, siblings);
	if (list_obj->parent != directory) {
	yaffs_trace(YAFFS_TRACE_ALWAYS,
	"Object in directory list has wrong parent %p",
	list_obj->parent);
	BUG();
	}
	yaffs_verify_obj_in_dir(list_obj);
	}
	}

	static int yaffs_free_verification_failures;

	void yaffs_verify_free_chunks(struct yaffs_dev *dev)
	{
	int counted;
	int difference;

	if (yaffs_skip_verification(dev))
	return;

	counted = yaffs_count_free_chunks(dev);

	difference = dev->n_free_chunks - counted;

	if (difference) {
	yaffs_trace(YAFFS_TRACE_ALWAYS,
	"Freechunks verification failure %d %d %d",
	dev->n_free_chunks, counted, difference);
	yaffs_free_verification_failures++;
	}
	}

	int yaffs_verify_file_sane(struct yaffs_obj *in)
	{
	return YAFFS_OK;
	}