- 根目录:
- fs
- udf
- 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/mutex.h>
uint32_t udf_get_pblock(struct super_block *sb, uint32_t block,
uint16_t partition, uint32_t offset)
{
struct udf_sb_info *sbi = UDF_SB(sb);
struct udf_part_map *map;
if (partition >= sbi->s_partitions) {
udf_debug("block=%d, partition=%d, offset=%d: invalid partition\n",
block, partition, offset);
return 0xFFFFFFFF;
}
map = &sbi->s_partmaps[partition];
if (map->s_partition_func)
return map->s_partition_func(sb, block, partition, offset);
else
return map->s_partition_root + 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;
struct udf_sb_info *sbi = UDF_SB(sb);
struct udf_part_map *map;
struct udf_virtual_data *vdata;
struct udf_inode_info *iinfo = UDF_I(sbi->s_vat_inode);
map = &sbi->s_partmaps[partition];
vdata = &map->s_type_specific.s_virtual;
if (block > vdata->s_num_entries) {
udf_debug("Trying to access block beyond end of VAT (%d max %d)\n",
block, vdata->s_num_entries);
return 0xFFFFFFFF;
}
if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
loc = le32_to_cpu(((__le32 *)(iinfo->i_ext.i_data +
vdata->s_start_offset))[block]);
goto translate;
}
index = (sb->s_blocksize - vdata->s_start_offset) / sizeof(uint32_t);
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 = vdata->s_start_offset / sizeof(uint32_t) + block;
}
loc = udf_block_map(sbi->s_vat_inode, newblock);
bh = sb_bread(sb, loc);
if (!bh) {
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);
translate:
if (iinfo->i_location.partitionReferenceNum == partition) {
udf_debug("recursive call to udf_get_pblock!\n");
return 0xFFFFFFFF;
}
return udf_get_pblock(sb, loc,
iinfo->i_location.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;
struct udf_sb_info *sbi = UDF_SB(sb);
struct udf_part_map *map;
uint32_t packet;
struct udf_sparing_data *sdata;
map = &sbi->s_partmaps[partition];
sdata = &map->s_type_specific.s_sparing;
packet = (block + offset) & ~(sdata->s_packet_len - 1);
for (i = 0; i < 4; i++) {
if (sdata->s_spar_map[i] != NULL) {
st = (struct sparingTable *)
sdata->s_spar_map[i]->b_data;
break;
}
}
if (st) {
for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {
struct sparingEntry *entry = &st->mapEntry[i];
u32 origLoc = le32_to_cpu(entry->origLocation);
if (origLoc >= 0xFFFFFFF0)
break;
else if (origLoc == packet)
return le32_to_cpu(entry->mappedLocation) +
((block + offset) &
(sdata->s_packet_len - 1));
else if (origLoc > packet)
break;
}
}
return map->s_partition_root + 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;
struct udf_sb_info *sbi = UDF_SB(sb);
u16 reallocationTableLen;
struct buffer_head *bh;
int ret = 0;
mutex_lock(&sbi->s_alloc_mutex);
for (i = 0; i < sbi->s_partitions; i++) {
struct udf_part_map *map = &sbi->s_partmaps[i];
if (old_block > map->s_partition_root &&
old_block < map->s_partition_root + map->s_partition_len) {
sdata = &map->s_type_specific.s_sparing;
packet = (old_block - map->s_partition_root) &
~(sdata->s_packet_len - 1);
for (j = 0; j < 4; j++)
if (sdata->s_spar_map[j] != NULL) {
st = (struct sparingTable *)
sdata->s_spar_map[j]->b_data;
break;
}
if (!st) {
ret = 1;
goto out;
}
reallocationTableLen =
le16_to_cpu(st->reallocationTableLen);
for (k = 0; k < reallocationTableLen; k++) {
struct sparingEntry *entry = &st->mapEntry[k];
u32 origLoc = le32_to_cpu(entry->origLocation);
if (origLoc == 0xFFFFFFFF) {
for (; j < 4; j++) {
int len;
bh = sdata->s_spar_map[j];
if (!bh)
continue;
st = (struct sparingTable *)
bh->b_data;
entry->origLocation =
cpu_to_le32(packet);
len =
sizeof(struct sparingTable) +
reallocationTableLen *
sizeof(struct sparingEntry);
udf_update_tag((char *)st, len);
mark_buffer_dirty(bh);
}
*new_block = le32_to_cpu(
entry->mappedLocation) +
((old_block -
map->s_partition_root) &
(sdata->s_packet_len - 1));
ret = 0;
goto out;
} else if (origLoc == packet) {
*new_block = le32_to_cpu(
entry->mappedLocation) +
((old_block -
map->s_partition_root) &
(sdata->s_packet_len - 1));
ret = 0;
goto out;
} else if (origLoc > packet)
break;
}
for (l = k; l < reallocationTableLen; l++) {
struct sparingEntry *entry = &st->mapEntry[l];
u32 origLoc = le32_to_cpu(entry->origLocation);
if (origLoc != 0xFFFFFFFF)
continue;
for (; j < 4; j++) {
bh = sdata->s_spar_map[j];
if (!bh)
continue;
st = (struct sparingTable *)bh->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) +
reallocationTableLen *
sizeof(struct sparingEntry));
mark_buffer_dirty(bh);
}
*new_block =
le32_to_cpu(
st->mapEntry[k].mappedLocation) +
((old_block - map->s_partition_root) &
(sdata->s_packet_len - 1));
ret = 0;
goto out;
}
ret = 1;
goto out;
} /* if old_block */
}
if (i == sbi->s_partitions) {
/* outside of partitions */
/* for now, fail =) */
ret = 1;
}
out:
mutex_unlock(&sbi->s_alloc_mutex);
return ret;
}
static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
uint16_t partition, uint32_t offset)
{
struct super_block *sb = inode->i_sb;
struct udf_part_map *map;
struct kernel_lb_addr eloc;
uint32_t elen;
sector_t ext_offset;
struct extent_position epos = {};
uint32_t phyblock;
if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) !=
(EXT_RECORDED_ALLOCATED >> 30))
phyblock = 0xFFFFFFFF;
else {
map = &UDF_SB(sb)->s_partmaps[partition];
/* map to sparable/physical partition desc */
phyblock = udf_get_pblock(sb, eloc.logicalBlockNum,
map->s_partition_num, ext_offset + offset);
}
brelse(epos.bh);
return phyblock;
}
uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
uint16_t partition, uint32_t offset)
{
struct udf_sb_info *sbi = UDF_SB(sb);
struct udf_part_map *map;
struct udf_meta_data *mdata;
uint32_t retblk;
struct inode *inode;
udf_debug("READING from METADATA\n");
map = &sbi->s_partmaps[partition];
mdata = &map->s_type_specific.s_metadata;
inode = mdata->s_metadata_fe ? : mdata->s_mirror_fe;
/* We shouldn't mount such media... */
BUG_ON(!inode);
retblk = udf_try_read_meta(inode, block, partition, offset);
if (retblk == 0xFFFFFFFF && mdata->s_metadata_fe) {
udf_warn(sb, "error reading from METADATA, trying to read from MIRROR\n");
if (!(mdata->s_flags & MF_MIRROR_FE_LOADED)) {
mdata->s_mirror_fe = udf_find_metadata_inode_efe(sb,
mdata->s_mirror_file_loc, map->s_partition_num);
mdata->s_flags |= MF_MIRROR_FE_LOADED;
}
inode = mdata->s_mirror_fe;
if (!inode)
return 0xFFFFFFFF;
retblk = udf_try_read_meta(inode, block, partition, offset);
}
return retblk;
}