/*
   * partition.c
   *
   * PURPOSE
   *      Partition handling routines for the OSTA-UDF(tm) filesystem.
   *

   * COPYRIGHT
   *      This file is distributed under the terms of the GNU General Public
   *      License (GPL). Copies of the GPL can be obtained from:
   *              ftp://prep.ai.mit.edu/pub/gnu/GPL
   *      Each contributing author retains all rights to their own work.
   *
   *  (C) 1998-2001 Ben Fennema
   *
   * HISTORY
   *

   * 12/06/98 blf  Created file.

   *
   */
  
  #include "udfdecl.h"
  #include "udf_sb.h"
  #include "udf_i.h"
  
  #include <linux/fs.h>
  #include <linux/string.h>
  #include <linux/udf_fs.h>
  #include <linux/slab.h>
  #include <linux/buffer_head.h>

  inline uint32_t udf_get_pblock(struct super_block *sb, uint32_t block,
  			       uint16_t partition, uint32_t offset)

  {

  	if (partition >= UDF_SB_NUMPARTS(sb)) {

  		udf_debug("block=%d, partition=%d, offset=%d: invalid partition
  ",
  			  block, partition, offset);

  		return 0xFFFFFFFF;
  	}
  	if (UDF_SB_PARTFUNC(sb, partition))

  		return UDF_SB_PARTFUNC(sb, partition)(sb, block, partition, offset);

  	else
  		return UDF_SB_PARTROOT(sb, partition) + block + offset;
  }

  uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block,

  			       uint16_t partition, uint32_t offset)

  {
  	struct buffer_head *bh = NULL;
  	uint32_t newblock;
  	uint32_t index;
  	uint32_t loc;

  	index = (sb->s_blocksize - UDF_SB_TYPEVIRT(sb,partition).s_start_offset) / sizeof(uint32_t);

  	if (block > UDF_SB_TYPEVIRT(sb,partition).s_num_entries) {
  		udf_debug("Trying to access block beyond end of VAT (%d max %d)
  ",
  			  block, UDF_SB_TYPEVIRT(sb,partition).s_num_entries);

  		return 0xFFFFFFFF;
  	}

  	if (block >= index) {

  		block -= index;
  		newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t)));
  		index = block % (sb->s_blocksize / sizeof(uint32_t));

  	} else {

  		newblock = 0;

  		index = UDF_SB_TYPEVIRT(sb,partition).s_start_offset / sizeof(uint32_t) + block;

  	}
  
  	loc = udf_block_map(UDF_SB_VAT(sb), newblock);

  	if (!(bh = sb_bread(sb, loc))) {

  		udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%d,%d) VAT: %d[%d]
  ",

  			  sb, block, partition, loc, index);

  		return 0xFFFFFFFF;
  	}

  	loc = le32_to_cpu(((__le32 *)bh->b_data)[index]);

  	brelse(bh);

  	if (UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum == partition) {

  		udf_debug("recursive call to udf_get_pblock!
  ");
  		return 0xFFFFFFFF;
  	}

  	return udf_get_pblock(sb, loc,

  			      UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum,
  			      offset);

  }

  inline uint32_t udf_get_pblock_virt20(struct super_block * sb, uint32_t block,
  				      uint16_t partition, uint32_t offset)

  {
  	return udf_get_pblock_virt15(sb, block, partition, offset);
  }

  uint32_t udf_get_pblock_spar15(struct super_block * sb, uint32_t block,
  			       uint16_t partition, uint32_t offset)

  {
  	int i;
  	struct sparingTable *st = NULL;

  	uint32_t packet = (block + offset) & ~(UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1);

  	for (i = 0; i < 4; i++) {

  		if (UDF_SB_TYPESPAR(sb,partition).s_spar_map[i] != NULL) {
  			st = (struct sparingTable *)UDF_SB_TYPESPAR(sb,partition).s_spar_map[i]->b_data;

  			break;
  		}
  	}

  	if (st) {
  		for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {

  			if (le32_to_cpu(st->mapEntry[i].origLocation) >= 0xFFFFFFF0) {

  				break;

  			} else if (le32_to_cpu(st->mapEntry[i].origLocation) == packet) {
  				return le32_to_cpu(st->mapEntry[i].mappedLocation) +
  					((block + offset) & (UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1));
  			} else if (le32_to_cpu(st->mapEntry[i].origLocation) > packet) {

  				break;

  			}

  		}
  	}

  
  	return UDF_SB_PARTROOT(sb,partition) + block + offset;

  }
  
  int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
  {
  	struct udf_sparing_data *sdata;
  	struct sparingTable *st = NULL;
  	struct sparingEntry mapEntry;
  	uint32_t packet;
  	int i, j, k, l;

  	for (i = 0; i < UDF_SB_NUMPARTS(sb); i++) {

  		if (old_block > UDF_SB_PARTROOT(sb,i) &&
  		    old_block < UDF_SB_PARTROOT(sb,i) + UDF_SB_PARTLEN(sb,i)) {
  			sdata = &UDF_SB_TYPESPAR(sb,i);
  			packet = (old_block - UDF_SB_PARTROOT(sb,i)) & ~(sdata->s_packet_len - 1);

  
  			for (j = 0; j < 4; j++) {

  				if (UDF_SB_TYPESPAR(sb,i).s_spar_map[j] != NULL) {
  					st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;

  					break;
  				}
  			}
  
  			if (!st)
  				return 1;

  			for (k = 0; k < le16_to_cpu(st->reallocationTableLen); k++) {
  				if (le32_to_cpu(st->mapEntry[k].origLocation) == 0xFFFFFFFF) {

  					for (; j < 4; j++) {
  						if (sdata->s_spar_map[j]) {

  							st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
  							st->mapEntry[k].origLocation = cpu_to_le32(packet);
  							udf_update_tag((char *)st, sizeof(struct sparingTable) + le16_to_cpu(st->reallocationTableLen) * sizeof(struct sparingEntry));
  							mark_buffer_dirty(sdata->s_spar_map[j]);

  						}
  					}

  					*new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
  						((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));

  					return 0;

  				} else if (le32_to_cpu(st->mapEntry[k].origLocation) == packet) {
  					*new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
  						((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));

  					return 0;

  				} else if (le32_to_cpu(st->mapEntry[k].origLocation) > packet) {

  					break;

  				}

  			}

  
  			for (l = k; l < le16_to_cpu(st->reallocationTableLen); l++) {
  				if (le32_to_cpu(st->mapEntry[l].origLocation) == 0xFFFFFFFF) {

  					for (; j < 4; j++) {
  						if (sdata->s_spar_map[j]) {

  							st = (struct sparingTable *)sdata->s_spar_map[j]->b_data;
  							mapEntry = st->mapEntry[l];
  							mapEntry.origLocation = cpu_to_le32(packet);
  							memmove(&st->mapEntry[k + 1], &st->mapEntry[k], (l - k) * sizeof(struct sparingEntry));
  							st->mapEntry[k] = mapEntry;
  							udf_update_tag((char *)st, sizeof(struct sparingTable) + le16_to_cpu(st->reallocationTableLen) * sizeof(struct sparingEntry));
  							mark_buffer_dirty(sdata->s_spar_map[j]);

  						}
  					}

  					*new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
  						((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));

  					return 0;
  				}
  			}

  			return 1;

  		} /* if old_block */

  	}

  	if (i == UDF_SB_NUMPARTS(sb)) {

  		/* outside of partitions */
  		/* for now, fail =) */
  		return 1;
  	}
  
  	return 0;
  }