/*
 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
 *
 * Copyright (C) 2002-2010 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)
{
	dev=dev;
	return !(yaffs_trace_mask & (YAFFS_TRACE_VERIFY | YAFFS_TRACE_VERIFY_FULL));
}

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

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


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


void yaffs_verify_blk(struct yaffs_dev *dev, yaffs_block_info_t *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)
		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has undefined state %d"TENDSTR), n, bi->block_state));

	switch (bi->block_state) {
	case YAFFS_BLOCK_STATE_UNKNOWN:
	case YAFFS_BLOCK_STATE_SCANNING:
	case YAFFS_BLOCK_STATE_NEEDS_SCANNING:
		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has bad run-state %s"TENDSTR),
		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)
		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has illegal values pages_in_used %d soft_del_pages %d"TENDSTR),
		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)
		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has inconsistent values pages_in_use %d counted chunk bits %d"TENDSTR),
			n, bi->pages_in_use, in_use));

}



void yaffs_verify_collected_blk(struct yaffs_dev *dev, yaffs_block_info_t *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) {
		T(YAFFS_TRACE_ERROR, (TSTR("Block %d is in state %d after gc, should be erased"TENDSTR),
			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++) {
		yaffs_block_info_t *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++;
	}

	T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));
	T(YAFFS_TRACE_VERIFY, (TSTR("Block summary"TENDSTR)));

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

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

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

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

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

	T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));

}

/*
 * 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)) {
		T(YAFFS_TRACE_VERIFY,
				(TSTR("Verifying object header tags %p obj %p oh %p"TENDSTR),
				tags, obj, oh));
		return;
	}

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

	if (tags->obj_id != obj->obj_id)
		T(YAFFS_TRACE_VERIFY,
			(TSTR("Obj %d header mismatch obj_id %d"TENDSTR),
			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)
		T(YAFFS_TRACE_VERIFY,
			(TSTR("Obj %d header mismatch parent_id %d obj->parent is NULL"TENDSTR),
			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))
		T(YAFFS_TRACE_VERIFY,
			(TSTR("Obj %d header mismatch parent_id %d parent_obj_id %d"TENDSTR),
			tags->obj_id, oh->parent_obj_id, obj->parent->obj_id));

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

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



void yaffs_verify_file(struct yaffs_obj *obj)
{
	int required_depth;
	int actual_depth;
	u32 last_chunk;
	u32 x;
	u32 i;
	struct yaffs_dev *dev;
	struct yaffs_ext_tags tags;
	yaffs_tnode_t *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 */
	last_chunk =  obj->variant.file_variant.file_size / dev->data_bytes_per_chunk + 1;
	x = last_chunk >> YAFFS_TNODES_LEVEL0_BITS;
	required_depth = 0;
	while (x > 0) {
		x >>= YAFFS_TNODES_INTERNAL_BITS;
		required_depth++;
	}

	actual_depth = obj->variant.file_variant.top_level;

	/* 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) {
			u32 the_chunk = yaffs_get_group_base(dev, tn, i);
			if (the_chunk > 0) {
				/* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),obj_id,i,the_chunk)); */
				yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL, &tags);
				if (tags.obj_id != obj_id || tags.chunk_id != i) {
					T(~0, (TSTR("Object %d chunk_id %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
						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)) {
		T(YAFFS_TRACE_VERIFY,
			(TSTR("Obj %d has chunk_id %d %s %s"TENDSTR),
			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, __LINE__);

		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, __LINE__);
	}

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

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

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

	if (yaffs_skip_verification(dev))
		return;

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

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


void yaffs_verify_obj_in_dir(struct yaffs_obj *obj)
{
	struct ylist_head *lh;
	struct yaffs_obj *list_obj;

	int count = 0;

	if (!obj) {
		T(YAFFS_TRACE_ALWAYS, (TSTR("No object to verify" TENDSTR)));
		YBUG();
		return;
	}

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

	if (!obj->parent) {
		T(YAFFS_TRACE_ALWAYS, (TSTR("Object does not have parent" TENDSTR)));
		YBUG();
		return;
	}

	if (obj->parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
		T(YAFFS_TRACE_ALWAYS, (TSTR("Parent is not directory" TENDSTR)));
		YBUG();
	}

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

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

	if (count != 1) {
		T(YAFFS_TRACE_ALWAYS, (TSTR("Object in directory %d times" TENDSTR), count));
		YBUG();
	}
}

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

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

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

	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
		T(YAFFS_TRACE_ALWAYS,
		(TSTR("Directory has wrong type: %d" TENDSTR),
		directory->variant_type));
		YBUG();
	}

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

	ylist_for_each(lh, &directory->variant.dir_variant.children) {
		if (lh) {
			list_obj = ylist_entry(lh, struct yaffs_obj, siblings);
			if (list_obj->parent != directory) {
				T(YAFFS_TRACE_ALWAYS, (
				TSTR("Object in directory list has wrong parent %p" TENDSTR),
				list_obj->parent));
				YBUG();
			}
			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) {
		T(YAFFS_TRACE_ALWAYS,
		  (TSTR("Freechunks verification failure %d %d %d" TENDSTR),
		   dev->n_free_chunks, counted, difference));
		yaffs_free_verification_failures++;
	}
}

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