5 * Block allocation handling routines for the OSTA-UDF(tm) filesystem.
8 * This file is distributed under the terms of the GNU General Public
9 * License (GPL). Copies of the GPL can be obtained from:
10 * ftp://prep.ai.mit.edu/pub/gnu/GPL
11 * Each contributing author retains all rights to their own work.
13 * (C) 1999-2001 Ben Fennema
14 * (C) 1999 Stelias Computing Inc
18 * 02/24/99 blf Created.
24 #include <linux/bitops.h>
29 #define udf_clear_bit __test_and_clear_bit_le
30 #define udf_set_bit __test_and_set_bit_le
31 #define udf_test_bit test_bit_le
32 #define udf_find_next_one_bit find_next_bit_le
34 static int read_block_bitmap(struct super_block
*sb
,
35 struct udf_bitmap
*bitmap
, unsigned int block
,
36 unsigned long bitmap_nr
)
38 struct buffer_head
*bh
= NULL
;
40 struct kernel_lb_addr loc
;
42 loc
.logicalBlockNum
= bitmap
->s_extPosition
;
43 loc
.partitionReferenceNum
= UDF_SB(sb
)->s_partition
;
45 bh
= udf_tread(sb
, udf_get_lb_pblock(sb
, &loc
, block
));
49 bitmap
->s_block_bitmap
[bitmap_nr
] = bh
;
53 static int __load_block_bitmap(struct super_block
*sb
,
54 struct udf_bitmap
*bitmap
,
55 unsigned int block_group
)
58 int nr_groups
= bitmap
->s_nr_groups
;
60 if (block_group
>= nr_groups
) {
61 udf_debug("block_group (%u) > nr_groups (%d)\n",
62 block_group
, nr_groups
);
65 if (bitmap
->s_block_bitmap
[block_group
])
68 retval
= read_block_bitmap(sb
, bitmap
, block_group
, block_group
);
75 static inline int load_block_bitmap(struct super_block
*sb
,
76 struct udf_bitmap
*bitmap
,
77 unsigned int block_group
)
81 slot
= __load_block_bitmap(sb
, bitmap
, block_group
);
86 if (!bitmap
->s_block_bitmap
[slot
])
92 static void udf_add_free_space(struct super_block
*sb
, u16 partition
, u32 cnt
)
94 struct udf_sb_info
*sbi
= UDF_SB(sb
);
95 struct logicalVolIntegrityDesc
*lvid
;
100 lvid
= (struct logicalVolIntegrityDesc
*)sbi
->s_lvid_bh
->b_data
;
101 le32_add_cpu(&lvid
->freeSpaceTable
[partition
], cnt
);
102 udf_updated_lvid(sb
);
105 static void udf_bitmap_free_blocks(struct super_block
*sb
,
106 struct udf_bitmap
*bitmap
,
107 struct kernel_lb_addr
*bloc
,
111 struct udf_sb_info
*sbi
= UDF_SB(sb
);
112 struct buffer_head
*bh
= NULL
;
113 struct udf_part_map
*partmap
;
115 unsigned long block_group
;
119 unsigned long overflow
;
121 mutex_lock(&sbi
->s_alloc_mutex
);
122 partmap
= &sbi
->s_partmaps
[bloc
->partitionReferenceNum
];
123 if (bloc
->logicalBlockNum
+ count
< count
||
124 (bloc
->logicalBlockNum
+ count
) > partmap
->s_partition_len
) {
125 udf_debug("%u < %d || %u + %u > %u\n",
126 bloc
->logicalBlockNum
, 0,
127 bloc
->logicalBlockNum
, count
,
128 partmap
->s_partition_len
);
132 block
= bloc
->logicalBlockNum
+ offset
+
133 (sizeof(struct spaceBitmapDesc
) << 3);
137 block_group
= block
>> (sb
->s_blocksize_bits
+ 3);
138 bit
= block
% (sb
->s_blocksize
<< 3);
141 * Check to see if we are freeing blocks across a group boundary.
143 if (bit
+ count
> (sb
->s_blocksize
<< 3)) {
144 overflow
= bit
+ count
- (sb
->s_blocksize
<< 3);
147 bitmap_nr
= load_block_bitmap(sb
, bitmap
, block_group
);
151 bh
= bitmap
->s_block_bitmap
[bitmap_nr
];
152 for (i
= 0; i
< count
; i
++) {
153 if (udf_set_bit(bit
+ i
, bh
->b_data
)) {
154 udf_debug("bit %lu already set\n", bit
+ i
);
155 udf_debug("byte=%2x\n",
156 ((__u8
*)bh
->b_data
)[(bit
+ i
) >> 3]);
159 udf_add_free_space(sb
, sbi
->s_partition
, count
);
160 mark_buffer_dirty(bh
);
168 mutex_unlock(&sbi
->s_alloc_mutex
);
171 static int udf_bitmap_prealloc_blocks(struct super_block
*sb
,
172 struct udf_bitmap
*bitmap
,
173 uint16_t partition
, uint32_t first_block
,
174 uint32_t block_count
)
176 struct udf_sb_info
*sbi
= UDF_SB(sb
);
178 int bit
, block
, block_group
, group_start
;
179 int nr_groups
, bitmap_nr
;
180 struct buffer_head
*bh
;
183 mutex_lock(&sbi
->s_alloc_mutex
);
184 part_len
= sbi
->s_partmaps
[partition
].s_partition_len
;
185 if (first_block
>= part_len
)
188 if (first_block
+ block_count
> part_len
)
189 block_count
= part_len
- first_block
;
192 nr_groups
= udf_compute_nr_groups(sb
, partition
);
193 block
= first_block
+ (sizeof(struct spaceBitmapDesc
) << 3);
194 block_group
= block
>> (sb
->s_blocksize_bits
+ 3);
195 group_start
= block_group
? 0 : sizeof(struct spaceBitmapDesc
);
197 bitmap_nr
= load_block_bitmap(sb
, bitmap
, block_group
);
200 bh
= bitmap
->s_block_bitmap
[bitmap_nr
];
202 bit
= block
% (sb
->s_blocksize
<< 3);
204 while (bit
< (sb
->s_blocksize
<< 3) && block_count
> 0) {
205 if (!udf_clear_bit(bit
, bh
->b_data
))
212 mark_buffer_dirty(bh
);
213 } while (block_count
> 0);
216 udf_add_free_space(sb
, partition
, -alloc_count
);
217 mutex_unlock(&sbi
->s_alloc_mutex
);
221 static udf_pblk_t
udf_bitmap_new_block(struct super_block
*sb
,
222 struct udf_bitmap
*bitmap
, uint16_t partition
,
223 uint32_t goal
, int *err
)
225 struct udf_sb_info
*sbi
= UDF_SB(sb
);
228 int block_group
, group_start
;
229 int end_goal
, nr_groups
, bitmap_nr
, i
;
230 struct buffer_head
*bh
= NULL
;
232 udf_pblk_t newblock
= 0;
235 mutex_lock(&sbi
->s_alloc_mutex
);
238 if (goal
>= sbi
->s_partmaps
[partition
].s_partition_len
)
241 nr_groups
= bitmap
->s_nr_groups
;
242 block
= goal
+ (sizeof(struct spaceBitmapDesc
) << 3);
243 block_group
= block
>> (sb
->s_blocksize_bits
+ 3);
244 group_start
= block_group
? 0 : sizeof(struct spaceBitmapDesc
);
246 bitmap_nr
= load_block_bitmap(sb
, bitmap
, block_group
);
249 bh
= bitmap
->s_block_bitmap
[bitmap_nr
];
250 ptr
= memscan((char *)bh
->b_data
+ group_start
, 0xFF,
251 sb
->s_blocksize
- group_start
);
253 if ((ptr
- ((char *)bh
->b_data
)) < sb
->s_blocksize
) {
254 bit
= block
% (sb
->s_blocksize
<< 3);
255 if (udf_test_bit(bit
, bh
->b_data
))
258 end_goal
= (bit
+ 63) & ~63;
259 bit
= udf_find_next_one_bit(bh
->b_data
, end_goal
, bit
);
263 ptr
= memscan((char *)bh
->b_data
+ (bit
>> 3), 0xFF,
264 sb
->s_blocksize
- ((bit
+ 7) >> 3));
265 newbit
= (ptr
- ((char *)bh
->b_data
)) << 3;
266 if (newbit
< sb
->s_blocksize
<< 3) {
271 newbit
= udf_find_next_one_bit(bh
->b_data
,
272 sb
->s_blocksize
<< 3, bit
);
273 if (newbit
< sb
->s_blocksize
<< 3) {
279 for (i
= 0; i
< (nr_groups
* 2); i
++) {
281 if (block_group
>= nr_groups
)
283 group_start
= block_group
? 0 : sizeof(struct spaceBitmapDesc
);
285 bitmap_nr
= load_block_bitmap(sb
, bitmap
, block_group
);
288 bh
= bitmap
->s_block_bitmap
[bitmap_nr
];
290 ptr
= memscan((char *)bh
->b_data
+ group_start
, 0xFF,
291 sb
->s_blocksize
- group_start
);
292 if ((ptr
- ((char *)bh
->b_data
)) < sb
->s_blocksize
) {
293 bit
= (ptr
- ((char *)bh
->b_data
)) << 3;
297 bit
= udf_find_next_one_bit(bh
->b_data
,
298 sb
->s_blocksize
<< 3,
300 if (bit
< sb
->s_blocksize
<< 3)
304 if (i
>= (nr_groups
* 2)) {
305 mutex_unlock(&sbi
->s_alloc_mutex
);
308 if (bit
< sb
->s_blocksize
<< 3)
311 bit
= udf_find_next_one_bit(bh
->b_data
, sb
->s_blocksize
<< 3,
313 if (bit
>= sb
->s_blocksize
<< 3) {
314 mutex_unlock(&sbi
->s_alloc_mutex
);
320 while (i
< 7 && bit
> (group_start
<< 3) &&
321 udf_test_bit(bit
- 1, bh
->b_data
)) {
327 newblock
= bit
+ (block_group
<< (sb
->s_blocksize_bits
+ 3)) -
328 (sizeof(struct spaceBitmapDesc
) << 3);
330 if (!udf_clear_bit(bit
, bh
->b_data
)) {
331 udf_debug("bit already cleared for block %d\n", bit
);
335 mark_buffer_dirty(bh
);
337 udf_add_free_space(sb
, partition
, -1);
338 mutex_unlock(&sbi
->s_alloc_mutex
);
344 mutex_unlock(&sbi
->s_alloc_mutex
);
348 static void udf_table_free_blocks(struct super_block
*sb
,
350 struct kernel_lb_addr
*bloc
,
354 struct udf_sb_info
*sbi
= UDF_SB(sb
);
355 struct udf_part_map
*partmap
;
358 struct kernel_lb_addr eloc
;
359 struct extent_position oepos
, epos
;
361 struct udf_inode_info
*iinfo
;
363 mutex_lock(&sbi
->s_alloc_mutex
);
364 partmap
= &sbi
->s_partmaps
[bloc
->partitionReferenceNum
];
365 if (bloc
->logicalBlockNum
+ count
< count
||
366 (bloc
->logicalBlockNum
+ count
) > partmap
->s_partition_len
) {
367 udf_debug("%u < %d || %u + %u > %u\n",
368 bloc
->logicalBlockNum
, 0,
369 bloc
->logicalBlockNum
, count
,
370 partmap
->s_partition_len
);
374 iinfo
= UDF_I(table
);
375 udf_add_free_space(sb
, sbi
->s_partition
, count
);
377 start
= bloc
->logicalBlockNum
+ offset
;
378 end
= bloc
->logicalBlockNum
+ offset
+ count
- 1;
380 epos
.offset
= oepos
.offset
= sizeof(struct unallocSpaceEntry
);
382 epos
.block
= oepos
.block
= iinfo
->i_location
;
383 epos
.bh
= oepos
.bh
= NULL
;
386 (etype
= udf_next_aext(table
, &epos
, &eloc
, &elen
, 1)) != -1) {
387 if (((eloc
.logicalBlockNum
+
388 (elen
>> sb
->s_blocksize_bits
)) == start
)) {
389 if ((0x3FFFFFFF - elen
) <
390 (count
<< sb
->s_blocksize_bits
)) {
391 uint32_t tmp
= ((0x3FFFFFFF - elen
) >>
392 sb
->s_blocksize_bits
);
395 elen
= (etype
<< 30) |
396 (0x40000000 - sb
->s_blocksize
);
398 elen
= (etype
<< 30) |
400 (count
<< sb
->s_blocksize_bits
));
404 udf_write_aext(table
, &oepos
, &eloc
, elen
, 1);
405 } else if (eloc
.logicalBlockNum
== (end
+ 1)) {
406 if ((0x3FFFFFFF - elen
) <
407 (count
<< sb
->s_blocksize_bits
)) {
408 uint32_t tmp
= ((0x3FFFFFFF - elen
) >>
409 sb
->s_blocksize_bits
);
412 eloc
.logicalBlockNum
-= tmp
;
413 elen
= (etype
<< 30) |
414 (0x40000000 - sb
->s_blocksize
);
416 eloc
.logicalBlockNum
= start
;
417 elen
= (etype
<< 30) |
419 (count
<< sb
->s_blocksize_bits
));
423 udf_write_aext(table
, &oepos
, &eloc
, elen
, 1);
426 if (epos
.bh
!= oepos
.bh
) {
427 oepos
.block
= epos
.block
;
433 oepos
.offset
= epos
.offset
;
439 * NOTE: we CANNOT use udf_add_aext here, as it can try to
440 * allocate a new block, and since we hold the super block
441 * lock already very bad things would happen :)
443 * We copy the behavior of udf_add_aext, but instead of
444 * trying to allocate a new block close to the existing one,
445 * we just steal a block from the extent we are trying to add.
447 * It would be nice if the blocks were close together, but it
453 eloc
.logicalBlockNum
= start
;
454 elen
= EXT_RECORDED_ALLOCATED
|
455 (count
<< sb
->s_blocksize_bits
);
457 if (iinfo
->i_alloc_type
== ICBTAG_FLAG_AD_SHORT
)
458 adsize
= sizeof(struct short_ad
);
459 else if (iinfo
->i_alloc_type
== ICBTAG_FLAG_AD_LONG
)
460 adsize
= sizeof(struct long_ad
);
467 if (epos
.offset
+ (2 * adsize
) > sb
->s_blocksize
) {
468 /* Steal a block from the extent being free'd */
469 udf_setup_indirect_aext(table
, eloc
.logicalBlockNum
,
472 eloc
.logicalBlockNum
++;
473 elen
-= sb
->s_blocksize
;
476 /* It's possible that stealing the block emptied the extent */
478 __udf_add_aext(table
, &epos
, &eloc
, elen
, 1);
485 mutex_unlock(&sbi
->s_alloc_mutex
);
489 static int udf_table_prealloc_blocks(struct super_block
*sb
,
490 struct inode
*table
, uint16_t partition
,
491 uint32_t first_block
, uint32_t block_count
)
493 struct udf_sb_info
*sbi
= UDF_SB(sb
);
495 uint32_t elen
, adsize
;
496 struct kernel_lb_addr eloc
;
497 struct extent_position epos
;
499 struct udf_inode_info
*iinfo
;
501 if (first_block
>= sbi
->s_partmaps
[partition
].s_partition_len
)
504 iinfo
= UDF_I(table
);
505 if (iinfo
->i_alloc_type
== ICBTAG_FLAG_AD_SHORT
)
506 adsize
= sizeof(struct short_ad
);
507 else if (iinfo
->i_alloc_type
== ICBTAG_FLAG_AD_LONG
)
508 adsize
= sizeof(struct long_ad
);
512 mutex_lock(&sbi
->s_alloc_mutex
);
513 epos
.offset
= sizeof(struct unallocSpaceEntry
);
514 epos
.block
= iinfo
->i_location
;
516 eloc
.logicalBlockNum
= 0xFFFFFFFF;
518 while (first_block
!= eloc
.logicalBlockNum
&&
519 (etype
= udf_next_aext(table
, &epos
, &eloc
, &elen
, 1)) != -1) {
520 udf_debug("eloc=%u, elen=%u, first_block=%u\n",
521 eloc
.logicalBlockNum
, elen
, first_block
);
522 ; /* empty loop body */
525 if (first_block
== eloc
.logicalBlockNum
) {
526 epos
.offset
-= adsize
;
528 alloc_count
= (elen
>> sb
->s_blocksize_bits
);
529 if (alloc_count
> block_count
) {
530 alloc_count
= block_count
;
531 eloc
.logicalBlockNum
+= alloc_count
;
532 elen
-= (alloc_count
<< sb
->s_blocksize_bits
);
533 udf_write_aext(table
, &epos
, &eloc
,
534 (etype
<< 30) | elen
, 1);
536 udf_delete_aext(table
, epos
);
544 udf_add_free_space(sb
, partition
, -alloc_count
);
545 mutex_unlock(&sbi
->s_alloc_mutex
);
549 static udf_pblk_t
udf_table_new_block(struct super_block
*sb
,
550 struct inode
*table
, uint16_t partition
,
551 uint32_t goal
, int *err
)
553 struct udf_sb_info
*sbi
= UDF_SB(sb
);
554 uint32_t spread
= 0xFFFFFFFF, nspread
= 0xFFFFFFFF;
555 udf_pblk_t newblock
= 0;
557 uint32_t elen
, goal_elen
= 0;
558 struct kernel_lb_addr eloc
, uninitialized_var(goal_eloc
);
559 struct extent_position epos
, goal_epos
;
561 struct udf_inode_info
*iinfo
= UDF_I(table
);
565 if (iinfo
->i_alloc_type
== ICBTAG_FLAG_AD_SHORT
)
566 adsize
= sizeof(struct short_ad
);
567 else if (iinfo
->i_alloc_type
== ICBTAG_FLAG_AD_LONG
)
568 adsize
= sizeof(struct long_ad
);
572 mutex_lock(&sbi
->s_alloc_mutex
);
573 if (goal
>= sbi
->s_partmaps
[partition
].s_partition_len
)
576 /* We search for the closest matching block to goal. If we find
577 a exact hit, we stop. Otherwise we keep going till we run out
578 of extents. We store the buffer_head, bloc, and extoffset
579 of the current closest match and use that when we are done.
581 epos
.offset
= sizeof(struct unallocSpaceEntry
);
582 epos
.block
= iinfo
->i_location
;
583 epos
.bh
= goal_epos
.bh
= NULL
;
586 (etype
= udf_next_aext(table
, &epos
, &eloc
, &elen
, 1)) != -1) {
587 if (goal
>= eloc
.logicalBlockNum
) {
588 if (goal
< eloc
.logicalBlockNum
+
589 (elen
>> sb
->s_blocksize_bits
))
592 nspread
= goal
- eloc
.logicalBlockNum
-
593 (elen
>> sb
->s_blocksize_bits
);
595 nspread
= eloc
.logicalBlockNum
- goal
;
598 if (nspread
< spread
) {
600 if (goal_epos
.bh
!= epos
.bh
) {
601 brelse(goal_epos
.bh
);
602 goal_epos
.bh
= epos
.bh
;
603 get_bh(goal_epos
.bh
);
605 goal_epos
.block
= epos
.block
;
606 goal_epos
.offset
= epos
.offset
- adsize
;
608 goal_elen
= (etype
<< 30) | elen
;
614 if (spread
== 0xFFFFFFFF) {
615 brelse(goal_epos
.bh
);
616 mutex_unlock(&sbi
->s_alloc_mutex
);
620 /* Only allocate blocks from the beginning of the extent.
621 That way, we only delete (empty) extents, never have to insert an
622 extent because of splitting */
623 /* This works, but very poorly.... */
625 newblock
= goal_eloc
.logicalBlockNum
;
626 goal_eloc
.logicalBlockNum
++;
627 goal_elen
-= sb
->s_blocksize
;
630 udf_write_aext(table
, &goal_epos
, &goal_eloc
, goal_elen
, 1);
632 udf_delete_aext(table
, goal_epos
);
633 brelse(goal_epos
.bh
);
635 udf_add_free_space(sb
, partition
, -1);
637 mutex_unlock(&sbi
->s_alloc_mutex
);
642 void udf_free_blocks(struct super_block
*sb
, struct inode
*inode
,
643 struct kernel_lb_addr
*bloc
, uint32_t offset
,
646 uint16_t partition
= bloc
->partitionReferenceNum
;
647 struct udf_part_map
*map
= &UDF_SB(sb
)->s_partmaps
[partition
];
649 if (map
->s_partition_flags
& UDF_PART_FLAG_UNALLOC_BITMAP
) {
650 udf_bitmap_free_blocks(sb
, map
->s_uspace
.s_bitmap
,
651 bloc
, offset
, count
);
652 } else if (map
->s_partition_flags
& UDF_PART_FLAG_UNALLOC_TABLE
) {
653 udf_table_free_blocks(sb
, map
->s_uspace
.s_table
,
654 bloc
, offset
, count
);
655 } else if (map
->s_partition_flags
& UDF_PART_FLAG_FREED_BITMAP
) {
656 udf_bitmap_free_blocks(sb
, map
->s_fspace
.s_bitmap
,
657 bloc
, offset
, count
);
658 } else if (map
->s_partition_flags
& UDF_PART_FLAG_FREED_TABLE
) {
659 udf_table_free_blocks(sb
, map
->s_fspace
.s_table
,
660 bloc
, offset
, count
);
664 inode_sub_bytes(inode
,
665 ((sector_t
)count
) << sb
->s_blocksize_bits
);
669 inline int udf_prealloc_blocks(struct super_block
*sb
,
671 uint16_t partition
, uint32_t first_block
,
672 uint32_t block_count
)
674 struct udf_part_map
*map
= &UDF_SB(sb
)->s_partmaps
[partition
];
677 if (map
->s_partition_flags
& UDF_PART_FLAG_UNALLOC_BITMAP
)
678 allocated
= udf_bitmap_prealloc_blocks(sb
,
679 map
->s_uspace
.s_bitmap
,
680 partition
, first_block
,
682 else if (map
->s_partition_flags
& UDF_PART_FLAG_UNALLOC_TABLE
)
683 allocated
= udf_table_prealloc_blocks(sb
,
684 map
->s_uspace
.s_table
,
685 partition
, first_block
,
687 else if (map
->s_partition_flags
& UDF_PART_FLAG_FREED_BITMAP
)
688 allocated
= udf_bitmap_prealloc_blocks(sb
,
689 map
->s_fspace
.s_bitmap
,
690 partition
, first_block
,
692 else if (map
->s_partition_flags
& UDF_PART_FLAG_FREED_TABLE
)
693 allocated
= udf_table_prealloc_blocks(sb
,
694 map
->s_fspace
.s_table
,
695 partition
, first_block
,
700 if (inode
&& allocated
> 0)
701 inode_add_bytes(inode
, allocated
<< sb
->s_blocksize_bits
);
705 inline udf_pblk_t
udf_new_block(struct super_block
*sb
,
707 uint16_t partition
, uint32_t goal
, int *err
)
709 struct udf_part_map
*map
= &UDF_SB(sb
)->s_partmaps
[partition
];
712 if (map
->s_partition_flags
& UDF_PART_FLAG_UNALLOC_BITMAP
)
713 block
= udf_bitmap_new_block(sb
,
714 map
->s_uspace
.s_bitmap
,
715 partition
, goal
, err
);
716 else if (map
->s_partition_flags
& UDF_PART_FLAG_UNALLOC_TABLE
)
717 block
= udf_table_new_block(sb
,
718 map
->s_uspace
.s_table
,
719 partition
, goal
, err
);
720 else if (map
->s_partition_flags
& UDF_PART_FLAG_FREED_BITMAP
)
721 block
= udf_bitmap_new_block(sb
,
722 map
->s_fspace
.s_bitmap
,
723 partition
, goal
, err
);
724 else if (map
->s_partition_flags
& UDF_PART_FLAG_FREED_TABLE
)
725 block
= udf_table_new_block(sb
,
726 map
->s_fspace
.s_table
,
727 partition
, goal
, err
);
733 inode_add_bytes(inode
, sb
->s_blocksize
);