/*
* 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@hootie.lvld.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) 1999-2000 Ben Fennema
* (C) 1999 Stelias Computing Inc
*
* HISTORY
*
* 02/24/99 blf Created.
*
*/
#include "udfdecl.h"
#include <linux/fs.h>
#include <linux/locks.h>
#include <linux/quotaops.h>
#include <linux/udf_fs.h>
#include <asm/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))
extern inline int find_next_one_bit (void * addr, int size, int offset)
{
unsigned long * p = ((unsigned long *) addr) + (offset / BITS_PER_LONG);
unsigned long 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, Uint32 bitmap,
unsigned int block, unsigned long bitmap_nr)
{
struct buffer_head *bh = NULL;
int retval = 0;
lb_addr loc;
loc.logicalBlockNum = bitmap;
loc.partitionReferenceNum = UDF_SB_PARTITION(sb);
bh = udf_tread(sb, udf_get_lb_pblock(sb, loc, block), sb->s_blocksize);
if (!bh)
{
retval = -EIO;
}
UDF_SB_BLOCK_BITMAP_NUMBER(sb, bitmap_nr) = block;
UDF_SB_BLOCK_BITMAP(sb, bitmap_nr) = bh;
return retval;
}
static int __load_block_bitmap(struct super_block * sb, Uint32 bitmap,
unsigned int block_group)
{
int i, j, retval = 0;
unsigned long block_bitmap_number;
struct buffer_head * block_bitmap = NULL;
int nr_groups = (UDF_SB_PARTLEN(sb, UDF_SB_PARTITION(sb)) +
(sizeof(struct SpaceBitmapDesc) << 3) + (sb->s_blocksize * 8) - 1) / (sb->s_blocksize * 8);
if (block_group >= nr_groups)
{
udf_debug("block_group (%d) > nr_groups (%d)\n", block_group, nr_groups);
}
if (nr_groups <= UDF_MAX_BLOCK_LOADED)
{
if (UDF_SB_BLOCK_BITMAP(sb, block_group))
{
if (UDF_SB_BLOCK_BITMAP_NUMBER(sb, block_group) == block_group)
return block_group;
}
retval = read_block_bitmap(sb, bitmap, block_group, block_group);
if (retval < 0)
return retval;
return block_group;
}
for (i=0; i<UDF_SB_LOADED_BLOCK_BITMAPS(sb) &&
UDF_SB_BLOCK_BITMAP_NUMBER(sb, i) != block_group; i++)
{
;
}
if (i < UDF_SB_LOADED_BLOCK_BITMAPS(sb) &&
UDF_SB_BLOCK_BITMAP_NUMBER(sb, i) == block_group)
{
block_bitmap_number = UDF_SB_BLOCK_BITMAP_NUMBER(sb, i);
block_bitmap = UDF_SB_BLOCK_BITMAP(sb, i);
for (j=i; j>0; j--)
{
UDF_SB_BLOCK_BITMAP_NUMBER(sb, j) = UDF_SB_BLOCK_BITMAP_NUMBER(sb, j-1);
UDF_SB_BLOCK_BITMAP(sb, j) = UDF_SB_BLOCK_BITMAP(sb, j-1);
}
UDF_SB_BLOCK_BITMAP_NUMBER(sb, 0) = block_bitmap_number;
UDF_SB_BLOCK_BITMAP(sb, 0) = block_bitmap;
if (!block_bitmap)
retval = read_block_bitmap(sb, bitmap, block_group, 0);
}
else
{
if (UDF_SB_LOADED_BLOCK_BITMAPS(sb) < UDF_MAX_BLOCK_LOADED)
UDF_SB_LOADED_BLOCK_BITMAPS(sb) ++;
else
brelse(UDF_SB_BLOCK_BITMAP(sb, UDF_MAX_BLOCK_LOADED-1));
for (j=UDF_SB_LOADED_BLOCK_BITMAPS(sb)-1; j>0; j--)
{
UDF_SB_BLOCK_BITMAP_NUMBER(sb, j) = UDF_SB_BLOCK_BITMAP_NUMBER(sb, j-1);
UDF_SB_BLOCK_BITMAP(sb, j) = UDF_SB_BLOCK_BITMAP(sb, j-1);
}
retval = read_block_bitmap(sb, bitmap, block_group, 0);
}
return retval;
}
static inline int load_block_bitmap(struct super_block *sb, Uint32 bitmap,
unsigned int block_group)
{
int slot;
int nr_groups = (UDF_SB_PARTLEN(sb, UDF_SB_PARTITION(sb)) +
(sizeof(struct SpaceBitmapDesc) << 3) + (sb->s_blocksize * 8) - 1) / (sb->s_blocksize * 8);
if (UDF_SB_LOADED_BLOCK_BITMAPS(sb) > 0 &&
UDF_SB_BLOCK_BITMAP_NUMBER(sb, 0) == block_group &&
UDF_SB_BLOCK_BITMAP(sb, block_group))
{
return 0;
}
else if (nr_groups <= UDF_MAX_BLOCK_LOADED &&
UDF_SB_BLOCK_BITMAP_NUMBER(sb, block_group) == block_group &&
UDF_SB_BLOCK_BITMAP(sb, block_group))
{
slot = block_group;
}
else
{
slot = __load_block_bitmap(sb, bitmap, block_group);
}
if (slot < 0)
return slot;
if (!UDF_SB_BLOCK_BITMAP(sb, slot))
return -EIO;
return slot;
}
static void udf_bitmap_free_blocks(const struct inode * inode, Uint32 bitmap,
lb_addr bloc, Uint32 offset, Uint32 count)
{
struct buffer_head * bh = NULL;
unsigned long block;
unsigned long block_group;
unsigned long bit;
unsigned long i;
int bitmap_nr;
unsigned long overflow;
struct super_block * sb;
sb = inode->i_sb;
if (!sb)
{
udf_debug("nonexistent device");
return;
}
lock_super(sb);
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 = UDF_SB_BLOCK_BITMAP(sb, 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
{
DQUOT_FREE_BLOCK(sb, 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, 1);
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), 1);
unlock_super(sb);
return;
}
static int udf_bitmap_prealloc_blocks(const struct inode * inode, Uint32 bitmap,
Uint16 partition, Uint32 first_block, Uint32 block_count)
{
int alloc_count = 0;
int bit, block, block_group, group_start;
int nr_groups, bitmap_nr;
struct buffer_head *bh;
struct super_block *sb;
sb = inode->i_sb;
if (!sb)
{
udf_debug("nonexistent device\n");
return 0;
}
lock_super(sb);
if (first_block < 0 || first_block >= UDF_SB_PARTLEN(sb, partition))
goto out;
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 = UDF_SB_BLOCK_BITMAP(sb, 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(sb, 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(sb, inode, 1);
goto out;
}
block_count --;
alloc_count ++;
bit ++;
block ++;
}
mark_buffer_dirty(bh, 1);
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), 1);
}
sb->s_dirt = 1;
unlock_super(sb);
return alloc_count;
}
static int udf_bitmap_new_block(const struct inode * inode, Uint32 bitmap,
Uint16 partition, Uint32 goal, int *err)
{
int tmp, newbit, bit=0, block, block_group, group_start;
int end_goal, nr_groups, bitmap_nr, i;
struct buffer_head *bh = NULL;
struct super_block *sb;
char *ptr;
int newblock = 0;
*err = -ENOSPC;
sb = inode->i_sb;
if (!sb)
{
udf_debug("nonexistent device\n");
return newblock;
}
lock_super(sb);
repeat:
if (goal < 0 || goal >= UDF_SB_PARTLEN(sb, partition))
goal = 0;
nr_groups = (UDF_SB_PARTLEN(sb, partition) +
(sizeof(struct SpaceBitmapDesc) << 3) + (sb->s_blocksize * 8) - 1) / (sb->s_blocksize * 8);
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 = UDF_SB_BLOCK_BITMAP(sb, 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 = UDF_SB_BLOCK_BITMAP(sb, 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))
{
unlock_super(sb);
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)
{
unlock_super(sb);
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 (DQUOT_ALLOC_BLOCK(sb, inode, 1))
{
unlock_super(sb);
*err = -EDQUOT;
return 0;
}
newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
(sizeof(struct SpaceBitmapDesc) << 3);
tmp = udf_get_pblock(sb, newblock, partition, 0);
if (!udf_clear_bit(bit, bh->b_data))
{
udf_debug("bit already cleared for block %d\n", bit);
goto repeat;
}
mark_buffer_dirty(bh, 1);
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), 1);
}
sb->s_dirt = 1;
unlock_super(sb);
*err = 0;
return newblock;
error_return:
*err = -EIO;
unlock_super(sb);
return 0;
}
inline void udf_free_blocks(const struct inode * inode, lb_addr bloc,
Uint32 offset, Uint32 count)
{
if (UDF_SB_PARTFLAGS(inode->i_sb, bloc.partitionReferenceNum) & UDF_PART_FLAG_UNALLOC_BITMAP)
{
return udf_bitmap_free_blocks(inode,
UDF_SB_PARTMAPS(inode->i_sb)[bloc.partitionReferenceNum].s_uspace.bitmap,
bloc, offset, count);
}
else if (UDF_SB_PARTFLAGS(inode->i_sb, bloc.partitionReferenceNum) & UDF_PART_FLAG_FREED_BITMAP)
{
return udf_bitmap_free_blocks(inode,
UDF_SB_PARTMAPS(inode->i_sb)[bloc.partitionReferenceNum].s_fspace.bitmap,
bloc, offset, count);
}
else
return;
}
inline int udf_prealloc_blocks(const struct inode * inode, Uint16 partition,
Uint32 first_block, Uint32 block_count)
{
if (UDF_SB_PARTFLAGS(inode->i_sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP)
{
return udf_bitmap_prealloc_blocks(inode,
UDF_SB_PARTMAPS(inode->i_sb)[partition].s_uspace.bitmap,
partition, first_block, block_count);
}
else if (UDF_SB_PARTFLAGS(inode->i_sb, partition) & UDF_PART_FLAG_FREED_BITMAP)
{
return udf_bitmap_prealloc_blocks(inode,
UDF_SB_PARTMAPS(inode->i_sb)[partition].s_fspace.bitmap,
partition, first_block, block_count);
}
else
return 0;
}
inline int udf_new_block(const struct inode * inode, Uint16 partition,
Uint32 goal, int *err)
{
if (UDF_SB_PARTFLAGS(inode->i_sb, partition) & UDF_PART_FLAG_UNALLOC_BITMAP)
{
return udf_bitmap_new_block(inode,
UDF_SB_PARTMAPS(inode->i_sb)[partition].s_uspace.bitmap,
partition, goal, err);
}
else if (UDF_SB_PARTFLAGS(inode->i_sb, partition) & UDF_PART_FLAG_FREED_BITMAP)
{
return udf_bitmap_new_block(inode,
UDF_SB_PARTMAPS(inode->i_sb)[partition].s_fspace.bitmap,
partition, goal, err);
}
else
{
*err = -EIO;
return 0;
}
}