https://github.com/torvalds/linux
Tip revision: 49914084e797530d9baaf51df9eda77babc98fa8 authored by Linus Torvalds on 24 January 2008, 22:58:37 UTC
Linux 2.6.24
Linux 2.6.24
Tip revision: 4991408
partition.c
/*
* 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\n",
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)\n",
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]\n",
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!\n");
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;
}