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kernel-fxtec-pro1x/fs/udf/balloc.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2 
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

959 lines
24 KiB
C
Raw Blame History

/*
* balloc.c
*
* PURPOSE
* Block allocation handling routines for the OSTA-UDF(tm) filesystem.
*
* CONTACTS
* E-mail regarding any portion of the Linux UDF file system should be
* directed to the development team mailing list (run by majordomo):
* linux_udf@hpesjro.fc.hp.com
*
* 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) 1999-2001 Ben Fennema
* (C) 1999 Stelias Computing Inc
*
* HISTORY
*
* 02/24/99 blf Created.
*
*/
#include "udfdecl.h"
#include <linux/quotaops.h>
#include <linux/buffer_head.h>
#include <linux/bitops.h>
#include "udf_i.h"
#include "udf_sb.h"
#define udf_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
#define udf_set_bit(nr,addr) ext2_set_bit(nr,addr)
#define udf_test_bit(nr, addr) ext2_test_bit(nr, addr)
#define udf_find_first_one_bit(addr, size) find_first_one_bit(addr, size)
#define udf_find_next_one_bit(addr, size, offset) find_next_one_bit(addr, size, offset)
#define leBPL_to_cpup(x) leNUM_to_cpup(BITS_PER_LONG, x)
#define leNUM_to_cpup(x,y) xleNUM_to_cpup(x,y)
#define xleNUM_to_cpup(x,y) (le ## x ## _to_cpup(y))
#define uintBPL_t uint(BITS_PER_LONG)
#define uint(x) xuint(x)
#define xuint(x) __le ## x
extern inline int find_next_one_bit (void * addr, int size, int offset)
{
uintBPL_t * p = ((uintBPL_t *) addr) + (offset / BITS_PER_LONG);
int result = offset & ~(BITS_PER_LONG-1);
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= (BITS_PER_LONG-1);
if (offset)
{
tmp = leBPL_to_cpup(p++);
tmp &= ~0UL << offset;
if (size < BITS_PER_LONG)
goto found_first;
if (tmp)
goto found_middle;
size -= BITS_PER_LONG;
result += BITS_PER_LONG;
}
while (size & ~(BITS_PER_LONG-1))
{
if ((tmp = leBPL_to_cpup(p++)))
goto found_middle;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = leBPL_to_cpup(p);
found_first:
tmp &= ~0UL >> (BITS_PER_LONG-size);
found_middle:
return result + ffz(~tmp);
}
#define find_first_one_bit(addr, size)\
find_next_one_bit((addr), (size), 0)
static int read_block_bitmap(struct super_block * sb,
struct udf_bitmap *bitmap, unsigned int block, unsigned long bitmap_nr)
{
struct buffer_head *bh = NULL;
int retval = 0;
kernel_lb_addr loc;
loc.logicalBlockNum = bitmap->s_extPosition;
loc.partitionReferenceNum = UDF_SB_PARTITION(sb);
bh = udf_tread(sb, udf_get_lb_pblock(sb, loc, block));
if (!bh)
{
retval = -EIO;
}
bitmap->s_block_bitmap[bitmap_nr] = bh;
return retval;
}
static int __load_block_bitmap(struct super_block * sb,
struct udf_bitmap *bitmap, unsigned int block_group)
{
int retval = 0;
int nr_groups = bitmap->s_nr_groups;
if (block_group >= nr_groups)
{
udf_debug("block_group (%d) > nr_groups (%d)\n", block_group, nr_groups);
}
if (bitmap->s_block_bitmap[block_group])
return block_group;
else
{
retval = read_block_bitmap(sb, bitmap, block_group, block_group);
if (retval < 0)
return retval;
return block_group;
}
}
static inline int load_block_bitmap(struct super_block * sb,
struct udf_bitmap *bitmap, unsigned int block_group)
{
int slot;
slot = __load_block_bitmap(sb, bitmap, block_group);
if (slot < 0)
return slot;
if (!bitmap->s_block_bitmap[slot])
return -EIO;
return slot;
}
static void udf_bitmap_free_blocks(struct super_block * sb,
struct inode * inode,
struct udf_bitmap *bitmap,
kernel_lb_addr bloc, uint32_t offset, uint32_t count)
{
struct udf_sb_info *sbi = UDF_SB(sb);
struct buffer_head * bh = NULL;
unsigned long block;
unsigned long block_group;
unsigned long bit;
unsigned long i;
int bitmap_nr;
unsigned long overflow;
down(&sbi->s_alloc_sem);
if (bloc.logicalBlockNum < 0 ||
(bloc.logicalBlockNum + count) > UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum))
{
udf_debug("%d < %d || %d + %d > %d\n",
bloc.logicalBlockNum, 0, bloc.logicalBlockNum, count,
UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum));
goto error_return;
}
block = bloc.logicalBlockNum + offset + (sizeof(struct spaceBitmapDesc) << 3);
do_more:
overflow = 0;
block_group = block >> (sb->s_blocksize_bits + 3);
bit = block % (sb->s_blocksize << 3);
/*
* Check to see if we are freeing blocks across a group boundary.
*/
if (bit + count > (sb->s_blocksize << 3))
{
overflow = bit + count - (sb->s_blocksize << 3);
count -= overflow;
}
bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
if (bitmap_nr < 0)
goto error_return;
bh = bitmap->s_block_bitmap[bitmap_nr];
for (i=0; i < count; i++)
{
if (udf_set_bit(bit + i, bh->b_data))
{
udf_debug("bit %ld already set\n", bit + i);
udf_debug("byte=%2x\n", ((char *)bh->b_data)[(bit + i) >> 3]);
}
else
{
if (inode)
DQUOT_FREE_BLOCK(inode, 1);
if (UDF_SB_LVIDBH(sb))
{
UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)] =
cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)])+1);
}
}
}
mark_buffer_dirty(bh);
if (overflow)
{
block += count;
count = overflow;
goto do_more;
}
error_return:
sb->s_dirt = 1;
if (UDF_SB_LVIDBH(sb))
mark_buffer_dirty(UDF_SB_LVIDBH(sb));
up(&sbi->s_alloc_sem);
return;
}
static int udf_bitmap_prealloc_blocks(struct super_block * sb,
struct inode * inode,
struct udf_bitmap *bitmap, uint16_t partition, uint32_t first_block,
uint32_t block_count)
{
struct udf_sb_info *sbi = UDF_SB(sb);
int alloc_count = 0;
int bit, block, block_group, group_start;
int nr_groups, bitmap_nr;
struct buffer_head *bh;
down(&sbi->s_alloc_sem);
if (first_block < 0 || first_block >= UDF_SB_PARTLEN(sb, partition))
goto out;
if (first_block + block_count > UDF_SB_PARTLEN(sb, partition))
block_count = UDF_SB_PARTLEN(sb, partition) - first_block;
repeat:
nr_groups = (UDF_SB_PARTLEN(sb, partition) +
(sizeof(struct spaceBitmapDesc) << 3) + (sb->s_blocksize * 8) - 1) / (sb->s_blocksize * 8);
block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
block_group = block >> (sb->s_blocksize_bits + 3);
group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
if (bitmap_nr < 0)
goto out;
bh = bitmap->s_block_bitmap[bitmap_nr];
bit = block % (sb->s_blocksize << 3);
while (bit < (sb->s_blocksize << 3) && block_count > 0)
{
if (!udf_test_bit(bit, bh->b_data))
goto out;
else if (DQUOT_PREALLOC_BLOCK(inode, 1))
goto out;
else if (!udf_clear_bit(bit, bh->b_data))
{
udf_debug("bit already cleared for block %d\n", bit);
DQUOT_FREE_BLOCK(inode, 1);
goto out;
}
block_count --;
alloc_count ++;
bit ++;
block ++;
}
mark_buffer_dirty(bh);
if (block_count > 0)
goto repeat;
out:
if (UDF_SB_LVIDBH(sb))
{
UDF_SB_LVID(sb)->freeSpaceTable[partition] =
cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-alloc_count);
mark_buffer_dirty(UDF_SB_LVIDBH(sb));
}
sb->s_dirt = 1;
up(&sbi->s_alloc_sem);
return alloc_count;
}
static int udf_bitmap_new_block(struct super_block * sb,
struct inode * inode,
struct udf_bitmap *bitmap, uint16_t partition, uint32_t goal, int *err)
{
struct udf_sb_info *sbi = UDF_SB(sb);
int newbit, bit=0, block, block_group, group_start;
int end_goal, nr_groups, bitmap_nr, i;
struct buffer_head *bh = NULL;
char *ptr;
int newblock = 0;
*err = -ENOSPC;
down(&sbi->s_alloc_sem);
repeat:
if (goal < 0 || goal >= UDF_SB_PARTLEN(sb, partition))
goal = 0;
nr_groups = bitmap->s_nr_groups;
block = goal + (sizeof(struct spaceBitmapDesc) << 3);
block_group = block >> (sb->s_blocksize_bits + 3);
group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
if (bitmap_nr < 0)
goto error_return;
bh = bitmap->s_block_bitmap[bitmap_nr];
ptr = memscan((char *)bh->b_data + group_start, 0xFF, sb->s_blocksize - group_start);
if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize)
{
bit = block % (sb->s_blocksize << 3);
if (udf_test_bit(bit, bh->b_data))
{
goto got_block;
}
end_goal = (bit + 63) & ~63;
bit = udf_find_next_one_bit(bh->b_data, end_goal, bit);
if (bit < end_goal)
goto got_block;
ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF, sb->s_blocksize - ((bit + 7) >> 3));
newbit = (ptr - ((char *)bh->b_data)) << 3;
if (newbit < sb->s_blocksize << 3)
{
bit = newbit;
goto search_back;
}
newbit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3, bit);
if (newbit < sb->s_blocksize << 3)
{
bit = newbit;
goto got_block;
}
}
for (i=0; i<(nr_groups*2); i++)
{
block_group ++;
if (block_group >= nr_groups)
block_group = 0;
group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
if (bitmap_nr < 0)
goto error_return;
bh = bitmap->s_block_bitmap[bitmap_nr];
if (i < nr_groups)
{
ptr = memscan((char *)bh->b_data + group_start, 0xFF, sb->s_blocksize - group_start);
if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize)
{
bit = (ptr - ((char *)bh->b_data)) << 3;
break;
}
}
else
{
bit = udf_find_next_one_bit((char *)bh->b_data, sb->s_blocksize << 3, group_start << 3);
if (bit < sb->s_blocksize << 3)
break;
}
}
if (i >= (nr_groups*2))
{
up(&sbi->s_alloc_sem);
return newblock;
}
if (bit < sb->s_blocksize << 3)
goto search_back;
else
bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3, group_start << 3);
if (bit >= sb->s_blocksize << 3)
{
up(&sbi->s_alloc_sem);
return 0;
}
search_back:
for (i=0; i<7 && bit > (group_start << 3) && udf_test_bit(bit - 1, bh->b_data); i++, bit--);
got_block:
/*
* Check quota for allocation of this block.
*/
if (inode && DQUOT_ALLOC_BLOCK(inode, 1))
{
up(&sbi->s_alloc_sem);
*err = -EDQUOT;
return 0;
}
newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
(sizeof(struct spaceBitmapDesc) << 3);
if (!udf_clear_bit(bit, bh->b_data))
{
udf_debug("bit already cleared for block %d\n", bit);
goto repeat;
}
mark_buffer_dirty(bh);
if (UDF_SB_LVIDBH(sb))
{
UDF_SB_LVID(sb)->freeSpaceTable[partition] =
cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-1);
mark_buffer_dirty(UDF_SB_LVIDBH(sb));
}
sb->s_dirt = 1;
up(&sbi->s_alloc_sem);
*err = 0;
return newblock;
error_return:
*err = -EIO;
up(&sbi->s_alloc_sem);
return 0;
}
static void udf_table_free_blocks(struct super_block * sb,
struct inode * inode,
struct inode * table,
kernel_lb_addr bloc, uint32_t offset, uint32_t count)
{
struct udf_sb_info *sbi = UDF_SB(sb);
uint32_t start, end;
uint32_t nextoffset, oextoffset, elen;
kernel_lb_addr nbloc, obloc, eloc;
struct buffer_head *obh, *nbh;
int8_t etype;
int i;
down(&sbi->s_alloc_sem);
if (bloc.logicalBlockNum < 0 ||
(bloc.logicalBlockNum + count) > UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum))
{
udf_debug("%d < %d || %d + %d > %d\n",
bloc.logicalBlockNum, 0, bloc.logicalBlockNum, count,
UDF_SB_PARTLEN(sb, bloc.partitionReferenceNum));
goto error_return;
}
/* We do this up front - There are some error conditions that could occure,
but.. oh well */
if (inode)
DQUOT_FREE_BLOCK(inode, count);
if (UDF_SB_LVIDBH(sb))
{
UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)] =
cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[UDF_SB_PARTITION(sb)])+count);
mark_buffer_dirty(UDF_SB_LVIDBH(sb));
}
start = bloc.logicalBlockNum + offset;
end = bloc.logicalBlockNum + offset + count - 1;
oextoffset = nextoffset = sizeof(struct unallocSpaceEntry);
elen = 0;
obloc = nbloc = UDF_I_LOCATION(table);
obh = nbh = NULL;
while (count && (etype =
udf_next_aext(table, &nbloc, &nextoffset, &eloc, &elen, &nbh, 1)) != -1)
{
if (((eloc.logicalBlockNum + (elen >> sb->s_blocksize_bits)) ==
start))
{
if ((0x3FFFFFFF - elen) < (count << sb->s_blocksize_bits))
{
count -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits);
start += ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits);
elen = (etype << 30) | (0x40000000 - sb->s_blocksize);
}
else
{
elen = (etype << 30) |
(elen + (count << sb->s_blocksize_bits));
start += count;
count = 0;
}
udf_write_aext(table, obloc, &oextoffset, eloc, elen, obh, 1);
}
else if (eloc.logicalBlockNum == (end + 1))
{
if ((0x3FFFFFFF - elen) < (count << sb->s_blocksize_bits))
{
count -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits);
end -= ((0x3FFFFFFF - elen) >> sb->s_blocksize_bits);
eloc.logicalBlockNum -=
((0x3FFFFFFF - elen) >> sb->s_blocksize_bits);
elen = (etype << 30) | (0x40000000 - sb->s_blocksize);
}
else
{
eloc.logicalBlockNum = start;
elen = (etype << 30) |
(elen + (count << sb->s_blocksize_bits));
end -= count;
count = 0;
}
udf_write_aext(table, obloc, &oextoffset, eloc, elen, obh, 1);
}
if (nbh != obh)
{
i = -1;
obloc = nbloc;
udf_release_data(obh);
atomic_inc(&nbh->b_count);
obh = nbh;
oextoffset = 0;
}
else
oextoffset = nextoffset;
}
if (count)
{
/* NOTE: we CANNOT use udf_add_aext here, as it can try to allocate
a new block, and since we hold the super block lock already
very bad things would happen :)
We copy the behavior of udf_add_aext, but instead of
trying to allocate a new block close to the existing one,
we just steal a block from the extent we are trying to add.
It would be nice if the blocks were close together, but it
isn't required.
*/
int adsize;
short_ad *sad = NULL;
long_ad *lad = NULL;
struct allocExtDesc *aed;
eloc.logicalBlockNum = start;
elen = EXT_RECORDED_ALLOCATED |
(count << sb->s_blocksize_bits);
if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT)
adsize = sizeof(short_ad);
else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG)
adsize = sizeof(long_ad);
else
{
udf_release_data(obh);
udf_release_data(nbh);
goto error_return;
}
if (nextoffset + (2 * adsize) > sb->s_blocksize)
{
char *sptr, *dptr;
int loffset;
udf_release_data(obh);
obh = nbh;
obloc = nbloc;
oextoffset = nextoffset;
/* Steal a block from the extent being free'd */
nbloc.logicalBlockNum = eloc.logicalBlockNum;
eloc.logicalBlockNum ++;
elen -= sb->s_blocksize;
if (!(nbh = udf_tread(sb,
udf_get_lb_pblock(sb, nbloc, 0))))
{
udf_release_data(obh);
goto error_return;
}
aed = (struct allocExtDesc *)(nbh->b_data);
aed->previousAllocExtLocation = cpu_to_le32(obloc.logicalBlockNum);
if (nextoffset + adsize > sb->s_blocksize)
{
loffset = nextoffset;
aed->lengthAllocDescs = cpu_to_le32(adsize);
if (obh)
sptr = UDF_I_DATA(inode) + nextoffset - udf_file_entry_alloc_offset(inode) + UDF_I_LENEATTR(inode) - adsize;
else
sptr = obh->b_data + nextoffset - adsize;
dptr = nbh->b_data + sizeof(struct allocExtDesc);
memcpy(dptr, sptr, adsize);
nextoffset = sizeof(struct allocExtDesc) + adsize;
}
else
{
loffset = nextoffset + adsize;
aed->lengthAllocDescs = cpu_to_le32(0);
sptr = (obh)->b_data + nextoffset;
nextoffset = sizeof(struct allocExtDesc);
if (obh)
{
aed = (struct allocExtDesc *)(obh)->b_data;
aed->lengthAllocDescs =
cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize);
}
else
{
UDF_I_LENALLOC(table) += adsize;
mark_inode_dirty(table);
}
}
if (UDF_SB_UDFREV(sb) >= 0x0200)
udf_new_tag(nbh->b_data, TAG_IDENT_AED, 3, 1,
nbloc.logicalBlockNum, sizeof(tag));
else
udf_new_tag(nbh->b_data, TAG_IDENT_AED, 2, 1,
nbloc.logicalBlockNum, sizeof(tag));
switch (UDF_I_ALLOCTYPE(table))
{
case ICBTAG_FLAG_AD_SHORT:
{
sad = (short_ad *)sptr;
sad->extLength = cpu_to_le32(
EXT_NEXT_EXTENT_ALLOCDECS |
sb->s_blocksize);
sad->extPosition = cpu_to_le32(nbloc.logicalBlockNum);
break;
}
case ICBTAG_FLAG_AD_LONG:
{
lad = (long_ad *)sptr;
lad->extLength = cpu_to_le32(
EXT_NEXT_EXTENT_ALLOCDECS |
sb->s_blocksize);
lad->extLocation = cpu_to_lelb(nbloc);
break;
}
}
if (obh)
{
udf_update_tag(obh->b_data, loffset);
mark_buffer_dirty(obh);
}
else
mark_inode_dirty(table);
}
if (elen) /* It's possible that stealing the block emptied the extent */
{
udf_write_aext(table, nbloc, &nextoffset, eloc, elen, nbh, 1);
if (!nbh)
{
UDF_I_LENALLOC(table) += adsize;
mark_inode_dirty(table);
}
else
{
aed = (struct allocExtDesc *)nbh->b_data;
aed->lengthAllocDescs =
cpu_to_le32(le32_to_cpu(aed->lengthAllocDescs) + adsize);
udf_update_tag(nbh->b_data, nextoffset);
mark_buffer_dirty(nbh);
}
}
}
udf_release_data(nbh);
udf_release_data(obh);
error_return:
sb->s_dirt = 1;
up(&sbi->s_alloc_sem);
return;
}
static int udf_table_prealloc_blocks(struct super_block * sb,
struct inode * inode,
struct inode *table, uint16_t partition, uint32_t first_block,
uint32_t block_count)
{
struct udf_sb_info *sbi = UDF_SB(sb);
int alloc_count = 0;
uint32_t extoffset, elen, adsize;
kernel_lb_addr bloc, eloc;
struct buffer_head *bh;
int8_t etype = -1;
if (first_block < 0 || first_block >= UDF_SB_PARTLEN(sb, partition))
return 0;
if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT)
adsize = sizeof(short_ad);
else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG)
adsize = sizeof(long_ad);
else
return 0;
down(&sbi->s_alloc_sem);
extoffset = sizeof(struct unallocSpaceEntry);
bloc = UDF_I_LOCATION(table);
bh = NULL;
eloc.logicalBlockNum = 0xFFFFFFFF;
while (first_block != eloc.logicalBlockNum && (etype =
udf_next_aext(table, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1)
{
udf_debug("eloc=%d, elen=%d, first_block=%d\n",
eloc.logicalBlockNum, elen, first_block);
; /* empty loop body */
}
if (first_block == eloc.logicalBlockNum)
{
extoffset -= adsize;
alloc_count = (elen >> sb->s_blocksize_bits);
if (inode && DQUOT_PREALLOC_BLOCK(inode, alloc_count > block_count ? block_count : alloc_count))
alloc_count = 0;
else if (alloc_count > block_count)
{
alloc_count = block_count;
eloc.logicalBlockNum += alloc_count;
elen -= (alloc_count << sb->s_blocksize_bits);
udf_write_aext(table, bloc, &extoffset, eloc, (etype << 30) | elen, bh, 1);
}
else
udf_delete_aext(table, bloc, extoffset, eloc, (etype << 30) | elen, bh);
}
else
alloc_count = 0;
udf_release_data(bh);
if (alloc_count && UDF_SB_LVIDBH(sb))
{
UDF_SB_LVID(sb)->freeSpaceTable[partition] =
cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-alloc_count);
mark_buffer_dirty(UDF_SB_LVIDBH(sb));
sb->s_dirt = 1;
}
up(&sbi->s_alloc_sem);
return alloc_count;
}
static int udf_table_new_block(struct super_block * sb,
struct inode * inode,
struct inode *table, uint16_t partition, uint32_t goal, int *err)
{
struct udf_sb_info *sbi = UDF_SB(sb);
uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
uint32_t newblock = 0, adsize;
uint32_t extoffset, goal_extoffset, elen, goal_elen = 0;
kernel_lb_addr bloc, goal_bloc, eloc, goal_eloc;
struct buffer_head *bh, *goal_bh;
int8_t etype;
*err = -ENOSPC;
if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_SHORT)
adsize = sizeof(short_ad);
else if (UDF_I_ALLOCTYPE(table) == ICBTAG_FLAG_AD_LONG)
adsize = sizeof(long_ad);
else
return newblock;
down(&sbi->s_alloc_sem);
if (goal < 0 || goal >= UDF_SB_PARTLEN(sb, partition))
goal = 0;
/* We search for the closest matching block to goal. If we find a exact hit,
we stop. Otherwise we keep going till we run out of extents.
We store the buffer_head, bloc, and extoffset of the current closest
match and use that when we are done.
*/
extoffset = sizeof(struct unallocSpaceEntry);
bloc = UDF_I_LOCATION(table);
goal_bh = bh = NULL;
while (spread && (etype =
udf_next_aext(table, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1)
{
if (goal >= eloc.logicalBlockNum)
{
if (goal < eloc.logicalBlockNum + (elen >> sb->s_blocksize_bits))
nspread = 0;
else
nspread = goal - eloc.logicalBlockNum -
(elen >> sb->s_blocksize_bits);
}
else
nspread = eloc.logicalBlockNum - goal;
if (nspread < spread)
{
spread = nspread;
if (goal_bh != bh)
{
udf_release_data(goal_bh);
goal_bh = bh;
atomic_inc(&goal_bh->b_count);
}
goal_bloc = bloc;
goal_extoffset = extoffset - adsize;
goal_eloc = eloc;
goal_elen = (etype << 30) | elen;
}
}
udf_release_data(bh);
if (spread == 0xFFFFFFFF)
{
udf_release_data(goal_bh);
up(&sbi->s_alloc_sem);
return 0;
}
/* Only allocate blocks from the beginning of the extent.
That way, we only delete (empty) extents, never have to insert an
extent because of splitting */
/* This works, but very poorly.... */
newblock = goal_eloc.logicalBlockNum;
goal_eloc.logicalBlockNum ++;
goal_elen -= sb->s_blocksize;
if (inode && DQUOT_ALLOC_BLOCK(inode, 1))
{
udf_release_data(goal_bh);
up(&sbi->s_alloc_sem);
*err = -EDQUOT;
return 0;
}
if (goal_elen)
udf_write_aext(table, goal_bloc, &goal_extoffset, goal_eloc, goal_elen, goal_bh, 1);
else
udf_delete_aext(table, goal_bloc, goal_extoffset, goal_eloc, goal_elen, goal_bh);
udf_release_data(goal_bh);
if (UDF_SB_LVIDBH(sb))
{
UDF_SB_LVID(sb)->freeSpaceTable[partition] =
cpu_to_le32(le32_to_cpu(UDF_SB_LVID(sb)->freeSpaceTable[partition])-1);
mark_buffer_dirty(UDF_SB_LVIDBH(sb));
}
sb->s_dirt = 1;
up(&sbi->s_alloc_sem);
*err = 0;
return newblock;
}
inline void udf_free_blocks(struct super_block * sb,
struct inode * inode,
kernel_lb_addr bloc, uint32_t offset, uint32_t count)
{
uint16_t partition = bloc.partitionReferenceNum;
if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP)
{
return udf_bitmap_free_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap,
bloc, offset, count);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE)
{
return udf_table_free_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table,
bloc, offset, count);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP)
{
return udf_bitmap_free_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap,
bloc, offset, count);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE)
{
return udf_table_free_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table,
bloc, offset, count);
}
else
return;
}
inline int udf_prealloc_blocks(struct super_block * sb,
struct inode * inode,
uint16_t partition, uint32_t first_block, uint32_t block_count)
{
if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP)
{
return udf_bitmap_prealloc_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap,
partition, first_block, block_count);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE)
{
return udf_table_prealloc_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table,
partition, first_block, block_count);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP)
{
return udf_bitmap_prealloc_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap,
partition, first_block, block_count);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE)
{
return udf_table_prealloc_blocks(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table,
partition, first_block, block_count);
}
else
return 0;
}
inline int udf_new_block(struct super_block * sb,
struct inode * inode,
uint16_t partition, uint32_t goal, int *err)
{
if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP)
{
return udf_bitmap_new_block(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_bitmap,
partition, goal, err);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_UNALLOC_TABLE)
{
return udf_table_new_block(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_uspace.s_table,
partition, goal, err);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_BITMAP)
{
return udf_bitmap_new_block(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_bitmap,
partition, goal, err);
}
else if (UDF_SB_PARTFLAGS(sb, partition) & UDF_PART_FLAG_FREED_TABLE)
{
return udf_table_new_block(sb, inode,
UDF_SB_PARTMAPS(sb)[partition].s_fspace.s_table,
partition, goal, err);
}
else
{
*err = -EIO;
return 0;
}
}
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