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1/*
2 * balloc.c
3 *
4 * PURPOSE
5 * Block allocation handling routines for the OSTA-UDF(tm) filesystem.
6 *
7 * COPYRIGHT
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.
12 *
13 * (C) 1999-2001 Ben Fennema
14 * (C) 1999 Stelias Computing Inc
15 *
16 * HISTORY
17 *
18 * 02/24/99 blf Created.
19 *
20 */
21
22#include "udfdecl.h"
23
24#include <linux/buffer_head.h>
25#include <linux/bitops.h>
26
27#include "udf_i.h"
28#include "udf_sb.h"
29
30#define udf_clear_bit __test_and_clear_bit_le
31#define udf_set_bit __test_and_set_bit_le
32#define udf_test_bit test_bit_le
33#define udf_find_next_one_bit find_next_bit_le
34
35static int read_block_bitmap(struct super_block *sb,
36 struct udf_bitmap *bitmap, unsigned int block,
37 unsigned long bitmap_nr)
38{
39 struct buffer_head *bh = NULL;
40 int retval = 0;
41 struct kernel_lb_addr loc;
42
43 loc.logicalBlockNum = bitmap->s_extPosition;
44 loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
45
46 bh = udf_tread(sb, udf_get_lb_pblock(sb, &loc, block));
47 if (!bh)
48 retval = -EIO;
49
50 bitmap->s_block_bitmap[bitmap_nr] = bh;
51 return retval;
52}
53
54static int __load_block_bitmap(struct super_block *sb,
55 struct udf_bitmap *bitmap,
56 unsigned int block_group)
57{
58 int retval = 0;
59 int nr_groups = bitmap->s_nr_groups;
60
61 if (block_group >= nr_groups) {
62 udf_debug("block_group (%d) > nr_groups (%d)\n",
63 block_group, nr_groups);
64 }
65
66 if (bitmap->s_block_bitmap[block_group]) {
67 return block_group;
68 } else {
69 retval = read_block_bitmap(sb, bitmap, block_group,
70 block_group);
71 if (retval < 0)
72 return retval;
73 return block_group;
74 }
75}
76
77static inline int load_block_bitmap(struct super_block *sb,
78 struct udf_bitmap *bitmap,
79 unsigned int block_group)
80{
81 int slot;
82
83 slot = __load_block_bitmap(sb, bitmap, block_group);
84
85 if (slot < 0)
86 return slot;
87
88 if (!bitmap->s_block_bitmap[slot])
89 return -EIO;
90
91 return slot;
92}
93
94static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt)
95{
96 struct udf_sb_info *sbi = UDF_SB(sb);
97 struct logicalVolIntegrityDesc *lvid;
98
99 if (!sbi->s_lvid_bh)
100 return;
101
102 lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data;
103 le32_add_cpu(&lvid->freeSpaceTable[partition], cnt);
104 udf_updated_lvid(sb);
105}
106
107static void udf_bitmap_free_blocks(struct super_block *sb,
108 struct udf_bitmap *bitmap,
109 struct kernel_lb_addr *bloc,
110 uint32_t offset,
111 uint32_t count)
112{
113 struct udf_sb_info *sbi = UDF_SB(sb);
114 struct buffer_head *bh = NULL;
115 struct udf_part_map *partmap;
116 unsigned long block;
117 unsigned long block_group;
118 unsigned long bit;
119 unsigned long i;
120 int bitmap_nr;
121 unsigned long overflow;
122
123 mutex_lock(&sbi->s_alloc_mutex);
124 partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
125 if (bloc->logicalBlockNum + count < count ||
126 (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
127 udf_debug("%d < %d || %d + %d > %d\n",
128 bloc->logicalBlockNum, 0,
129 bloc->logicalBlockNum, count,
130 partmap->s_partition_len);
131 goto error_return;
132 }
133
134 block = bloc->logicalBlockNum + offset +
135 (sizeof(struct spaceBitmapDesc) << 3);
136
137 do {
138 overflow = 0;
139 block_group = block >> (sb->s_blocksize_bits + 3);
140 bit = block % (sb->s_blocksize << 3);
141
142 /*
143 * Check to see if we are freeing blocks across a group boundary.
144 */
145 if (bit + count > (sb->s_blocksize << 3)) {
146 overflow = bit + count - (sb->s_blocksize << 3);
147 count -= overflow;
148 }
149 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
150 if (bitmap_nr < 0)
151 goto error_return;
152
153 bh = bitmap->s_block_bitmap[bitmap_nr];
154 for (i = 0; i < count; i++) {
155 if (udf_set_bit(bit + i, bh->b_data)) {
156 udf_debug("bit %ld already set\n", bit + i);
157 udf_debug("byte=%2x\n",
158 ((char *)bh->b_data)[(bit + i) >> 3]);
159 }
160 }
161 udf_add_free_space(sb, sbi->s_partition, count);
162 mark_buffer_dirty(bh);
163 if (overflow) {
164 block += count;
165 count = overflow;
166 }
167 } while (overflow);
168
169error_return:
170 mutex_unlock(&sbi->s_alloc_mutex);
171}
172
173static int udf_bitmap_prealloc_blocks(struct super_block *sb,
174 struct udf_bitmap *bitmap,
175 uint16_t partition, uint32_t first_block,
176 uint32_t block_count)
177{
178 struct udf_sb_info *sbi = UDF_SB(sb);
179 int alloc_count = 0;
180 int bit, block, block_group, group_start;
181 int nr_groups, bitmap_nr;
182 struct buffer_head *bh;
183 __u32 part_len;
184
185 mutex_lock(&sbi->s_alloc_mutex);
186 part_len = sbi->s_partmaps[partition].s_partition_len;
187 if (first_block >= part_len)
188 goto out;
189
190 if (first_block + block_count > part_len)
191 block_count = part_len - first_block;
192
193 do {
194 nr_groups = udf_compute_nr_groups(sb, partition);
195 block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
196 block_group = block >> (sb->s_blocksize_bits + 3);
197 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
198
199 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
200 if (bitmap_nr < 0)
201 goto out;
202 bh = bitmap->s_block_bitmap[bitmap_nr];
203
204 bit = block % (sb->s_blocksize << 3);
205
206 while (bit < (sb->s_blocksize << 3) && block_count > 0) {
207 if (!udf_clear_bit(bit, bh->b_data))
208 goto out;
209 block_count--;
210 alloc_count++;
211 bit++;
212 block++;
213 }
214 mark_buffer_dirty(bh);
215 } while (block_count > 0);
216
217out:
218 udf_add_free_space(sb, partition, -alloc_count);
219 mutex_unlock(&sbi->s_alloc_mutex);
220 return alloc_count;
221}
222
223static int udf_bitmap_new_block(struct super_block *sb,
224 struct udf_bitmap *bitmap, uint16_t partition,
225 uint32_t goal, int *err)
226{
227 struct udf_sb_info *sbi = UDF_SB(sb);
228 int newbit, bit = 0, block, block_group, group_start;
229 int end_goal, nr_groups, bitmap_nr, i;
230 struct buffer_head *bh = NULL;
231 char *ptr;
232 int newblock = 0;
233
234 *err = -ENOSPC;
235 mutex_lock(&sbi->s_alloc_mutex);
236
237repeat:
238 if (goal >= sbi->s_partmaps[partition].s_partition_len)
239 goal = 0;
240
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);
245
246 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
247 if (bitmap_nr < 0)
248 goto error_return;
249 bh = bitmap->s_block_bitmap[bitmap_nr];
250 ptr = memscan((char *)bh->b_data + group_start, 0xFF,
251 sb->s_blocksize - group_start);
252
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))
256 goto got_block;
257
258 end_goal = (bit + 63) & ~63;
259 bit = udf_find_next_one_bit(bh->b_data, end_goal, bit);
260 if (bit < end_goal)
261 goto got_block;
262
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) {
267 bit = newbit;
268 goto search_back;
269 }
270
271 newbit = udf_find_next_one_bit(bh->b_data,
272 sb->s_blocksize << 3, bit);
273 if (newbit < sb->s_blocksize << 3) {
274 bit = newbit;
275 goto got_block;
276 }
277 }
278
279 for (i = 0; i < (nr_groups * 2); i++) {
280 block_group++;
281 if (block_group >= nr_groups)
282 block_group = 0;
283 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
284
285 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
286 if (bitmap_nr < 0)
287 goto error_return;
288 bh = bitmap->s_block_bitmap[bitmap_nr];
289 if (i < nr_groups) {
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;
294 break;
295 }
296 } else {
297 bit = udf_find_next_one_bit(bh->b_data,
298 sb->s_blocksize << 3,
299 group_start << 3);
300 if (bit < sb->s_blocksize << 3)
301 break;
302 }
303 }
304 if (i >= (nr_groups * 2)) {
305 mutex_unlock(&sbi->s_alloc_mutex);
306 return newblock;
307 }
308 if (bit < sb->s_blocksize << 3)
309 goto search_back;
310 else
311 bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3,
312 group_start << 3);
313 if (bit >= sb->s_blocksize << 3) {
314 mutex_unlock(&sbi->s_alloc_mutex);
315 return 0;
316 }
317
318search_back:
319 i = 0;
320 while (i < 7 && bit > (group_start << 3) &&
321 udf_test_bit(bit - 1, bh->b_data)) {
322 ++i;
323 --bit;
324 }
325
326got_block:
327 newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
328 (sizeof(struct spaceBitmapDesc) << 3);
329
330 if (!udf_clear_bit(bit, bh->b_data)) {
331 udf_debug("bit already cleared for block %d\n", bit);
332 goto repeat;
333 }
334
335 mark_buffer_dirty(bh);
336
337 udf_add_free_space(sb, partition, -1);
338 mutex_unlock(&sbi->s_alloc_mutex);
339 *err = 0;
340 return newblock;
341
342error_return:
343 *err = -EIO;
344 mutex_unlock(&sbi->s_alloc_mutex);
345 return 0;
346}
347
348static void udf_table_free_blocks(struct super_block *sb,
349 struct inode *table,
350 struct kernel_lb_addr *bloc,
351 uint32_t offset,
352 uint32_t count)
353{
354 struct udf_sb_info *sbi = UDF_SB(sb);
355 struct udf_part_map *partmap;
356 uint32_t start, end;
357 uint32_t elen;
358 struct kernel_lb_addr eloc;
359 struct extent_position oepos, epos;
360 int8_t etype;
361 int i;
362 struct udf_inode_info *iinfo;
363
364 mutex_lock(&sbi->s_alloc_mutex);
365 partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
366 if (bloc->logicalBlockNum + count < count ||
367 (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
368 udf_debug("%d < %d || %d + %d > %d\n",
369 bloc->logicalBlockNum, 0,
370 bloc->logicalBlockNum, count,
371 partmap->s_partition_len);
372 goto error_return;
373 }
374
375 iinfo = UDF_I(table);
376 udf_add_free_space(sb, sbi->s_partition, count);
377
378 start = bloc->logicalBlockNum + offset;
379 end = bloc->logicalBlockNum + offset + count - 1;
380
381 epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry);
382 elen = 0;
383 epos.block = oepos.block = iinfo->i_location;
384 epos.bh = oepos.bh = NULL;
385
386 while (count &&
387 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
388 if (((eloc.logicalBlockNum +
389 (elen >> sb->s_blocksize_bits)) == start)) {
390 if ((0x3FFFFFFF - elen) <
391 (count << sb->s_blocksize_bits)) {
392 uint32_t tmp = ((0x3FFFFFFF - elen) >>
393 sb->s_blocksize_bits);
394 count -= tmp;
395 start += tmp;
396 elen = (etype << 30) |
397 (0x40000000 - sb->s_blocksize);
398 } else {
399 elen = (etype << 30) |
400 (elen +
401 (count << sb->s_blocksize_bits));
402 start += count;
403 count = 0;
404 }
405 udf_write_aext(table, &oepos, &eloc, elen, 1);
406 } else if (eloc.logicalBlockNum == (end + 1)) {
407 if ((0x3FFFFFFF - elen) <
408 (count << sb->s_blocksize_bits)) {
409 uint32_t tmp = ((0x3FFFFFFF - elen) >>
410 sb->s_blocksize_bits);
411 count -= tmp;
412 end -= tmp;
413 eloc.logicalBlockNum -= tmp;
414 elen = (etype << 30) |
415 (0x40000000 - sb->s_blocksize);
416 } else {
417 eloc.logicalBlockNum = start;
418 elen = (etype << 30) |
419 (elen +
420 (count << sb->s_blocksize_bits));
421 end -= count;
422 count = 0;
423 }
424 udf_write_aext(table, &oepos, &eloc, elen, 1);
425 }
426
427 if (epos.bh != oepos.bh) {
428 i = -1;
429 oepos.block = epos.block;
430 brelse(oepos.bh);
431 get_bh(epos.bh);
432 oepos.bh = epos.bh;
433 oepos.offset = 0;
434 } else {
435 oepos.offset = epos.offset;
436 }
437 }
438
439 if (count) {
440 /*
441 * NOTE: we CANNOT use udf_add_aext here, as it can try to
442 * allocate a new block, and since we hold the super block
443 * lock already very bad things would happen :)
444 *
445 * We copy the behavior of udf_add_aext, but instead of
446 * trying to allocate a new block close to the existing one,
447 * we just steal a block from the extent we are trying to add.
448 *
449 * It would be nice if the blocks were close together, but it
450 * isn't required.
451 */
452
453 int adsize;
454 struct short_ad *sad = NULL;
455 struct long_ad *lad = NULL;
456 struct allocExtDesc *aed;
457
458 eloc.logicalBlockNum = start;
459 elen = EXT_RECORDED_ALLOCATED |
460 (count << sb->s_blocksize_bits);
461
462 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
463 adsize = sizeof(struct short_ad);
464 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
465 adsize = sizeof(struct long_ad);
466 else {
467 brelse(oepos.bh);
468 brelse(epos.bh);
469 goto error_return;
470 }
471
472 if (epos.offset + (2 * adsize) > sb->s_blocksize) {
473 unsigned char *sptr, *dptr;
474 int loffset;
475
476 brelse(oepos.bh);
477 oepos = epos;
478
479 /* Steal a block from the extent being free'd */
480 epos.block.logicalBlockNum = eloc.logicalBlockNum;
481 eloc.logicalBlockNum++;
482 elen -= sb->s_blocksize;
483
484 epos.bh = udf_tread(sb,
485 udf_get_lb_pblock(sb, &epos.block, 0));
486 if (!epos.bh) {
487 brelse(oepos.bh);
488 goto error_return;
489 }
490 aed = (struct allocExtDesc *)(epos.bh->b_data);
491 aed->previousAllocExtLocation =
492 cpu_to_le32(oepos.block.logicalBlockNum);
493 if (epos.offset + adsize > sb->s_blocksize) {
494 loffset = epos.offset;
495 aed->lengthAllocDescs = cpu_to_le32(adsize);
496 sptr = iinfo->i_ext.i_data + epos.offset
497 - adsize;
498 dptr = epos.bh->b_data +
499 sizeof(struct allocExtDesc);
500 memcpy(dptr, sptr, adsize);
501 epos.offset = sizeof(struct allocExtDesc) +
502 adsize;
503 } else {
504 loffset = epos.offset + adsize;
505 aed->lengthAllocDescs = cpu_to_le32(0);
506 if (oepos.bh) {
507 sptr = oepos.bh->b_data + epos.offset;
508 aed = (struct allocExtDesc *)
509 oepos.bh->b_data;
510 le32_add_cpu(&aed->lengthAllocDescs,
511 adsize);
512 } else {
513 sptr = iinfo->i_ext.i_data +
514 epos.offset;
515 iinfo->i_lenAlloc += adsize;
516 mark_inode_dirty(table);
517 }
518 epos.offset = sizeof(struct allocExtDesc);
519 }
520 if (sbi->s_udfrev >= 0x0200)
521 udf_new_tag(epos.bh->b_data, TAG_IDENT_AED,
522 3, 1, epos.block.logicalBlockNum,
523 sizeof(struct tag));
524 else
525 udf_new_tag(epos.bh->b_data, TAG_IDENT_AED,
526 2, 1, epos.block.logicalBlockNum,
527 sizeof(struct tag));
528
529 switch (iinfo->i_alloc_type) {
530 case ICBTAG_FLAG_AD_SHORT:
531 sad = (struct short_ad *)sptr;
532 sad->extLength = cpu_to_le32(
533 EXT_NEXT_EXTENT_ALLOCDECS |
534 sb->s_blocksize);
535 sad->extPosition =
536 cpu_to_le32(epos.block.logicalBlockNum);
537 break;
538 case ICBTAG_FLAG_AD_LONG:
539 lad = (struct long_ad *)sptr;
540 lad->extLength = cpu_to_le32(
541 EXT_NEXT_EXTENT_ALLOCDECS |
542 sb->s_blocksize);
543 lad->extLocation =
544 cpu_to_lelb(epos.block);
545 break;
546 }
547 if (oepos.bh) {
548 udf_update_tag(oepos.bh->b_data, loffset);
549 mark_buffer_dirty(oepos.bh);
550 } else {
551 mark_inode_dirty(table);
552 }
553 }
554
555 /* It's possible that stealing the block emptied the extent */
556 if (elen) {
557 udf_write_aext(table, &epos, &eloc, elen, 1);
558
559 if (!epos.bh) {
560 iinfo->i_lenAlloc += adsize;
561 mark_inode_dirty(table);
562 } else {
563 aed = (struct allocExtDesc *)epos.bh->b_data;
564 le32_add_cpu(&aed->lengthAllocDescs, adsize);
565 udf_update_tag(epos.bh->b_data, epos.offset);
566 mark_buffer_dirty(epos.bh);
567 }
568 }
569 }
570
571 brelse(epos.bh);
572 brelse(oepos.bh);
573
574error_return:
575 mutex_unlock(&sbi->s_alloc_mutex);
576 return;
577}
578
579static int udf_table_prealloc_blocks(struct super_block *sb,
580 struct inode *table, uint16_t partition,
581 uint32_t first_block, uint32_t block_count)
582{
583 struct udf_sb_info *sbi = UDF_SB(sb);
584 int alloc_count = 0;
585 uint32_t elen, adsize;
586 struct kernel_lb_addr eloc;
587 struct extent_position epos;
588 int8_t etype = -1;
589 struct udf_inode_info *iinfo;
590
591 if (first_block >= sbi->s_partmaps[partition].s_partition_len)
592 return 0;
593
594 iinfo = UDF_I(table);
595 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
596 adsize = sizeof(struct short_ad);
597 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
598 adsize = sizeof(struct long_ad);
599 else
600 return 0;
601
602 mutex_lock(&sbi->s_alloc_mutex);
603 epos.offset = sizeof(struct unallocSpaceEntry);
604 epos.block = iinfo->i_location;
605 epos.bh = NULL;
606 eloc.logicalBlockNum = 0xFFFFFFFF;
607
608 while (first_block != eloc.logicalBlockNum &&
609 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
610 udf_debug("eloc=%d, elen=%d, first_block=%d\n",
611 eloc.logicalBlockNum, elen, first_block);
612 ; /* empty loop body */
613 }
614
615 if (first_block == eloc.logicalBlockNum) {
616 epos.offset -= adsize;
617
618 alloc_count = (elen >> sb->s_blocksize_bits);
619 if (alloc_count > block_count) {
620 alloc_count = block_count;
621 eloc.logicalBlockNum += alloc_count;
622 elen -= (alloc_count << sb->s_blocksize_bits);
623 udf_write_aext(table, &epos, &eloc,
624 (etype << 30) | elen, 1);
625 } else
626 udf_delete_aext(table, epos, eloc,
627 (etype << 30) | elen);
628 } else {
629 alloc_count = 0;
630 }
631
632 brelse(epos.bh);
633
634 if (alloc_count)
635 udf_add_free_space(sb, partition, -alloc_count);
636 mutex_unlock(&sbi->s_alloc_mutex);
637 return alloc_count;
638}
639
640static int udf_table_new_block(struct super_block *sb,
641 struct inode *table, uint16_t partition,
642 uint32_t goal, int *err)
643{
644 struct udf_sb_info *sbi = UDF_SB(sb);
645 uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
646 uint32_t newblock = 0, adsize;
647 uint32_t elen, goal_elen = 0;
648 struct kernel_lb_addr eloc, uninitialized_var(goal_eloc);
649 struct extent_position epos, goal_epos;
650 int8_t etype;
651 struct udf_inode_info *iinfo = UDF_I(table);
652
653 *err = -ENOSPC;
654
655 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
656 adsize = sizeof(struct short_ad);
657 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
658 adsize = sizeof(struct long_ad);
659 else
660 return newblock;
661
662 mutex_lock(&sbi->s_alloc_mutex);
663 if (goal >= sbi->s_partmaps[partition].s_partition_len)
664 goal = 0;
665
666 /* We search for the closest matching block to goal. If we find
667 a exact hit, we stop. Otherwise we keep going till we run out
668 of extents. We store the buffer_head, bloc, and extoffset
669 of the current closest match and use that when we are done.
670 */
671 epos.offset = sizeof(struct unallocSpaceEntry);
672 epos.block = iinfo->i_location;
673 epos.bh = goal_epos.bh = NULL;
674
675 while (spread &&
676 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
677 if (goal >= eloc.logicalBlockNum) {
678 if (goal < eloc.logicalBlockNum +
679 (elen >> sb->s_blocksize_bits))
680 nspread = 0;
681 else
682 nspread = goal - eloc.logicalBlockNum -
683 (elen >> sb->s_blocksize_bits);
684 } else {
685 nspread = eloc.logicalBlockNum - goal;
686 }
687
688 if (nspread < spread) {
689 spread = nspread;
690 if (goal_epos.bh != epos.bh) {
691 brelse(goal_epos.bh);
692 goal_epos.bh = epos.bh;
693 get_bh(goal_epos.bh);
694 }
695 goal_epos.block = epos.block;
696 goal_epos.offset = epos.offset - adsize;
697 goal_eloc = eloc;
698 goal_elen = (etype << 30) | elen;
699 }
700 }
701
702 brelse(epos.bh);
703
704 if (spread == 0xFFFFFFFF) {
705 brelse(goal_epos.bh);
706 mutex_unlock(&sbi->s_alloc_mutex);
707 return 0;
708 }
709
710 /* Only allocate blocks from the beginning of the extent.
711 That way, we only delete (empty) extents, never have to insert an
712 extent because of splitting */
713 /* This works, but very poorly.... */
714
715 newblock = goal_eloc.logicalBlockNum;
716 goal_eloc.logicalBlockNum++;
717 goal_elen -= sb->s_blocksize;
718
719 if (goal_elen)
720 udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1);
721 else
722 udf_delete_aext(table, goal_epos, goal_eloc, goal_elen);
723 brelse(goal_epos.bh);
724
725 udf_add_free_space(sb, partition, -1);
726
727 mutex_unlock(&sbi->s_alloc_mutex);
728 *err = 0;
729 return newblock;
730}
731
732void udf_free_blocks(struct super_block *sb, struct inode *inode,
733 struct kernel_lb_addr *bloc, uint32_t offset,
734 uint32_t count)
735{
736 uint16_t partition = bloc->partitionReferenceNum;
737 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
738
739 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
740 udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap,
741 bloc, offset, count);
742 } else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
743 udf_table_free_blocks(sb, map->s_uspace.s_table,
744 bloc, offset, count);
745 } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) {
746 udf_bitmap_free_blocks(sb, map->s_fspace.s_bitmap,
747 bloc, offset, count);
748 } else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) {
749 udf_table_free_blocks(sb, map->s_fspace.s_table,
750 bloc, offset, count);
751 }
752
753 if (inode) {
754 inode_sub_bytes(inode,
755 ((sector_t)count) << sb->s_blocksize_bits);
756 }
757}
758
759inline int udf_prealloc_blocks(struct super_block *sb,
760 struct inode *inode,
761 uint16_t partition, uint32_t first_block,
762 uint32_t block_count)
763{
764 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
765 sector_t allocated;
766
767 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
768 allocated = udf_bitmap_prealloc_blocks(sb,
769 map->s_uspace.s_bitmap,
770 partition, first_block,
771 block_count);
772 else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
773 allocated = udf_table_prealloc_blocks(sb,
774 map->s_uspace.s_table,
775 partition, first_block,
776 block_count);
777 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
778 allocated = udf_bitmap_prealloc_blocks(sb,
779 map->s_fspace.s_bitmap,
780 partition, first_block,
781 block_count);
782 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
783 allocated = udf_table_prealloc_blocks(sb,
784 map->s_fspace.s_table,
785 partition, first_block,
786 block_count);
787 else
788 return 0;
789
790 if (inode && allocated > 0)
791 inode_add_bytes(inode, allocated << sb->s_blocksize_bits);
792 return allocated;
793}
794
795inline int udf_new_block(struct super_block *sb,
796 struct inode *inode,
797 uint16_t partition, uint32_t goal, int *err)
798{
799 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
800 int block;
801
802 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
803 block = udf_bitmap_new_block(sb,
804 map->s_uspace.s_bitmap,
805 partition, goal, err);
806 else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
807 block = udf_table_new_block(sb,
808 map->s_uspace.s_table,
809 partition, goal, err);
810 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
811 block = udf_bitmap_new_block(sb,
812 map->s_fspace.s_bitmap,
813 partition, goal, err);
814 else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
815 block = udf_table_new_block(sb,
816 map->s_fspace.s_table,
817 partition, goal, err);
818 else {
819 *err = -EIO;
820 return 0;
821 }
822 if (inode && block)
823 inode_add_bytes(inode, sb->s_blocksize);
824 return block;
825}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * balloc.c
4 *
5 * PURPOSE
6 * Block allocation handling routines for the OSTA-UDF(tm) filesystem.
7 *
8 * COPYRIGHT
9 * (C) 1999-2001 Ben Fennema
10 * (C) 1999 Stelias Computing Inc
11 *
12 * HISTORY
13 *
14 * 02/24/99 blf Created.
15 *
16 */
17
18#include "udfdecl.h"
19
20#include <linux/bitops.h>
21
22#include "udf_i.h"
23#include "udf_sb.h"
24
25#define udf_clear_bit __test_and_clear_bit_le
26#define udf_set_bit __test_and_set_bit_le
27#define udf_test_bit test_bit_le
28#define udf_find_next_one_bit find_next_bit_le
29
30static int read_block_bitmap(struct super_block *sb,
31 struct udf_bitmap *bitmap, unsigned int block,
32 unsigned long bitmap_nr)
33{
34 struct buffer_head *bh = NULL;
35 int i;
36 int max_bits, off, count;
37 struct kernel_lb_addr loc;
38
39 loc.logicalBlockNum = bitmap->s_extPosition;
40 loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
41
42 bh = sb_bread(sb, udf_get_lb_pblock(sb, &loc, block));
43 bitmap->s_block_bitmap[bitmap_nr] = bh;
44 if (!bh)
45 return -EIO;
46
47 /* Check consistency of Space Bitmap buffer. */
48 max_bits = sb->s_blocksize * 8;
49 if (!bitmap_nr) {
50 off = sizeof(struct spaceBitmapDesc) << 3;
51 count = min(max_bits - off, bitmap->s_nr_groups);
52 } else {
53 /*
54 * Rough check if bitmap number is too big to have any bitmap
55 * blocks reserved.
56 */
57 if (bitmap_nr >
58 (bitmap->s_nr_groups >> (sb->s_blocksize_bits + 3)) + 2)
59 return 0;
60 off = 0;
61 count = bitmap->s_nr_groups - bitmap_nr * max_bits +
62 (sizeof(struct spaceBitmapDesc) << 3);
63 count = min(count, max_bits);
64 }
65
66 for (i = 0; i < count; i++)
67 if (udf_test_bit(i + off, bh->b_data))
68 return -EFSCORRUPTED;
69 return 0;
70}
71
72static int __load_block_bitmap(struct super_block *sb,
73 struct udf_bitmap *bitmap,
74 unsigned int block_group)
75{
76 int retval = 0;
77 int nr_groups = bitmap->s_nr_groups;
78
79 if (block_group >= nr_groups) {
80 udf_debug("block_group (%u) > nr_groups (%d)\n",
81 block_group, nr_groups);
82 }
83
84 if (bitmap->s_block_bitmap[block_group])
85 return block_group;
86
87 retval = read_block_bitmap(sb, bitmap, block_group, block_group);
88 if (retval < 0)
89 return retval;
90
91 return block_group;
92}
93
94static inline int load_block_bitmap(struct super_block *sb,
95 struct udf_bitmap *bitmap,
96 unsigned int block_group)
97{
98 int slot;
99
100 slot = __load_block_bitmap(sb, bitmap, block_group);
101
102 if (slot < 0)
103 return slot;
104
105 if (!bitmap->s_block_bitmap[slot])
106 return -EIO;
107
108 return slot;
109}
110
111static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt)
112{
113 struct udf_sb_info *sbi = UDF_SB(sb);
114 struct logicalVolIntegrityDesc *lvid;
115
116 if (!sbi->s_lvid_bh)
117 return;
118
119 lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data;
120 le32_add_cpu(&lvid->freeSpaceTable[partition], cnt);
121 udf_updated_lvid(sb);
122}
123
124static void udf_bitmap_free_blocks(struct super_block *sb,
125 struct udf_bitmap *bitmap,
126 struct kernel_lb_addr *bloc,
127 uint32_t offset,
128 uint32_t count)
129{
130 struct udf_sb_info *sbi = UDF_SB(sb);
131 struct buffer_head *bh = NULL;
132 struct udf_part_map *partmap;
133 unsigned long block;
134 unsigned long block_group;
135 unsigned long bit;
136 unsigned long i;
137 int bitmap_nr;
138 unsigned long overflow;
139
140 mutex_lock(&sbi->s_alloc_mutex);
141 partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
142 if (bloc->logicalBlockNum + count < count ||
143 (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
144 udf_debug("%u < %d || %u + %u > %u\n",
145 bloc->logicalBlockNum, 0,
146 bloc->logicalBlockNum, count,
147 partmap->s_partition_len);
148 goto error_return;
149 }
150
151 block = bloc->logicalBlockNum + offset +
152 (sizeof(struct spaceBitmapDesc) << 3);
153
154 do {
155 overflow = 0;
156 block_group = block >> (sb->s_blocksize_bits + 3);
157 bit = block % (sb->s_blocksize << 3);
158
159 /*
160 * Check to see if we are freeing blocks across a group boundary.
161 */
162 if (bit + count > (sb->s_blocksize << 3)) {
163 overflow = bit + count - (sb->s_blocksize << 3);
164 count -= overflow;
165 }
166 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
167 if (bitmap_nr < 0)
168 goto error_return;
169
170 bh = bitmap->s_block_bitmap[bitmap_nr];
171 for (i = 0; i < count; i++) {
172 if (udf_set_bit(bit + i, bh->b_data)) {
173 udf_debug("bit %lu already set\n", bit + i);
174 udf_debug("byte=%2x\n",
175 ((__u8 *)bh->b_data)[(bit + i) >> 3]);
176 }
177 }
178 udf_add_free_space(sb, sbi->s_partition, count);
179 mark_buffer_dirty(bh);
180 if (overflow) {
181 block += count;
182 count = overflow;
183 }
184 } while (overflow);
185
186error_return:
187 mutex_unlock(&sbi->s_alloc_mutex);
188}
189
190static int udf_bitmap_prealloc_blocks(struct super_block *sb,
191 struct udf_bitmap *bitmap,
192 uint16_t partition, uint32_t first_block,
193 uint32_t block_count)
194{
195 struct udf_sb_info *sbi = UDF_SB(sb);
196 int alloc_count = 0;
197 int bit, block, block_group;
198 int bitmap_nr;
199 struct buffer_head *bh;
200 __u32 part_len;
201
202 mutex_lock(&sbi->s_alloc_mutex);
203 part_len = sbi->s_partmaps[partition].s_partition_len;
204 if (first_block >= part_len)
205 goto out;
206
207 if (first_block + block_count > part_len)
208 block_count = part_len - first_block;
209
210 do {
211 block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
212 block_group = block >> (sb->s_blocksize_bits + 3);
213
214 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
215 if (bitmap_nr < 0)
216 goto out;
217 bh = bitmap->s_block_bitmap[bitmap_nr];
218
219 bit = block % (sb->s_blocksize << 3);
220
221 while (bit < (sb->s_blocksize << 3) && block_count > 0) {
222 if (!udf_clear_bit(bit, bh->b_data))
223 goto out;
224 block_count--;
225 alloc_count++;
226 bit++;
227 block++;
228 }
229 mark_buffer_dirty(bh);
230 } while (block_count > 0);
231
232out:
233 udf_add_free_space(sb, partition, -alloc_count);
234 mutex_unlock(&sbi->s_alloc_mutex);
235 return alloc_count;
236}
237
238static udf_pblk_t udf_bitmap_new_block(struct super_block *sb,
239 struct udf_bitmap *bitmap, uint16_t partition,
240 uint32_t goal, int *err)
241{
242 struct udf_sb_info *sbi = UDF_SB(sb);
243 int newbit, bit = 0;
244 udf_pblk_t block;
245 int block_group, group_start;
246 int end_goal, nr_groups, bitmap_nr, i;
247 struct buffer_head *bh = NULL;
248 char *ptr;
249 udf_pblk_t newblock = 0;
250
251 *err = -ENOSPC;
252 mutex_lock(&sbi->s_alloc_mutex);
253
254repeat:
255 if (goal >= sbi->s_partmaps[partition].s_partition_len)
256 goal = 0;
257
258 nr_groups = bitmap->s_nr_groups;
259 block = goal + (sizeof(struct spaceBitmapDesc) << 3);
260 block_group = block >> (sb->s_blocksize_bits + 3);
261 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
262
263 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
264 if (bitmap_nr < 0)
265 goto error_return;
266 bh = bitmap->s_block_bitmap[bitmap_nr];
267 ptr = memscan((char *)bh->b_data + group_start, 0xFF,
268 sb->s_blocksize - group_start);
269
270 if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
271 bit = block % (sb->s_blocksize << 3);
272 if (udf_test_bit(bit, bh->b_data))
273 goto got_block;
274
275 end_goal = (bit + 63) & ~63;
276 bit = udf_find_next_one_bit(bh->b_data, end_goal, bit);
277 if (bit < end_goal)
278 goto got_block;
279
280 ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF,
281 sb->s_blocksize - ((bit + 7) >> 3));
282 newbit = (ptr - ((char *)bh->b_data)) << 3;
283 if (newbit < sb->s_blocksize << 3) {
284 bit = newbit;
285 goto search_back;
286 }
287
288 newbit = udf_find_next_one_bit(bh->b_data,
289 sb->s_blocksize << 3, bit);
290 if (newbit < sb->s_blocksize << 3) {
291 bit = newbit;
292 goto got_block;
293 }
294 }
295
296 for (i = 0; i < (nr_groups * 2); i++) {
297 block_group++;
298 if (block_group >= nr_groups)
299 block_group = 0;
300 group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
301
302 bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
303 if (bitmap_nr < 0)
304 goto error_return;
305 bh = bitmap->s_block_bitmap[bitmap_nr];
306 if (i < nr_groups) {
307 ptr = memscan((char *)bh->b_data + group_start, 0xFF,
308 sb->s_blocksize - group_start);
309 if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
310 bit = (ptr - ((char *)bh->b_data)) << 3;
311 break;
312 }
313 } else {
314 bit = udf_find_next_one_bit(bh->b_data,
315 sb->s_blocksize << 3,
316 group_start << 3);
317 if (bit < sb->s_blocksize << 3)
318 break;
319 }
320 }
321 if (i >= (nr_groups * 2)) {
322 mutex_unlock(&sbi->s_alloc_mutex);
323 return newblock;
324 }
325 if (bit < sb->s_blocksize << 3)
326 goto search_back;
327 else
328 bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3,
329 group_start << 3);
330 if (bit >= sb->s_blocksize << 3) {
331 mutex_unlock(&sbi->s_alloc_mutex);
332 return 0;
333 }
334
335search_back:
336 i = 0;
337 while (i < 7 && bit > (group_start << 3) &&
338 udf_test_bit(bit - 1, bh->b_data)) {
339 ++i;
340 --bit;
341 }
342
343got_block:
344 newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
345 (sizeof(struct spaceBitmapDesc) << 3);
346
347 if (newblock >= sbi->s_partmaps[partition].s_partition_len) {
348 /*
349 * Ran off the end of the bitmap, and bits following are
350 * non-compliant (not all zero)
351 */
352 udf_err(sb, "bitmap for partition %d corrupted (block %u marked"
353 " as free, partition length is %u)\n", partition,
354 newblock, sbi->s_partmaps[partition].s_partition_len);
355 goto error_return;
356 }
357
358 if (!udf_clear_bit(bit, bh->b_data)) {
359 udf_debug("bit already cleared for block %d\n", bit);
360 goto repeat;
361 }
362
363 mark_buffer_dirty(bh);
364
365 udf_add_free_space(sb, partition, -1);
366 mutex_unlock(&sbi->s_alloc_mutex);
367 *err = 0;
368 return newblock;
369
370error_return:
371 *err = -EIO;
372 mutex_unlock(&sbi->s_alloc_mutex);
373 return 0;
374}
375
376static void udf_table_free_blocks(struct super_block *sb,
377 struct inode *table,
378 struct kernel_lb_addr *bloc,
379 uint32_t offset,
380 uint32_t count)
381{
382 struct udf_sb_info *sbi = UDF_SB(sb);
383 struct udf_part_map *partmap;
384 uint32_t start, end;
385 uint32_t elen;
386 struct kernel_lb_addr eloc;
387 struct extent_position oepos, epos;
388 int8_t etype;
389 struct udf_inode_info *iinfo;
390
391 mutex_lock(&sbi->s_alloc_mutex);
392 partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
393 if (bloc->logicalBlockNum + count < count ||
394 (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
395 udf_debug("%u < %d || %u + %u > %u\n",
396 bloc->logicalBlockNum, 0,
397 bloc->logicalBlockNum, count,
398 partmap->s_partition_len);
399 goto error_return;
400 }
401
402 iinfo = UDF_I(table);
403 udf_add_free_space(sb, sbi->s_partition, count);
404
405 start = bloc->logicalBlockNum + offset;
406 end = bloc->logicalBlockNum + offset + count - 1;
407
408 epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry);
409 elen = 0;
410 epos.block = oepos.block = iinfo->i_location;
411 epos.bh = oepos.bh = NULL;
412
413 while (count &&
414 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
415 if (((eloc.logicalBlockNum +
416 (elen >> sb->s_blocksize_bits)) == start)) {
417 if ((0x3FFFFFFF - elen) <
418 (count << sb->s_blocksize_bits)) {
419 uint32_t tmp = ((0x3FFFFFFF - elen) >>
420 sb->s_blocksize_bits);
421 count -= tmp;
422 start += tmp;
423 elen = (etype << 30) |
424 (0x40000000 - sb->s_blocksize);
425 } else {
426 elen = (etype << 30) |
427 (elen +
428 (count << sb->s_blocksize_bits));
429 start += count;
430 count = 0;
431 }
432 udf_write_aext(table, &oepos, &eloc, elen, 1);
433 } else if (eloc.logicalBlockNum == (end + 1)) {
434 if ((0x3FFFFFFF - elen) <
435 (count << sb->s_blocksize_bits)) {
436 uint32_t tmp = ((0x3FFFFFFF - elen) >>
437 sb->s_blocksize_bits);
438 count -= tmp;
439 end -= tmp;
440 eloc.logicalBlockNum -= tmp;
441 elen = (etype << 30) |
442 (0x40000000 - sb->s_blocksize);
443 } else {
444 eloc.logicalBlockNum = start;
445 elen = (etype << 30) |
446 (elen +
447 (count << sb->s_blocksize_bits));
448 end -= count;
449 count = 0;
450 }
451 udf_write_aext(table, &oepos, &eloc, elen, 1);
452 }
453
454 if (epos.bh != oepos.bh) {
455 oepos.block = epos.block;
456 brelse(oepos.bh);
457 get_bh(epos.bh);
458 oepos.bh = epos.bh;
459 oepos.offset = 0;
460 } else {
461 oepos.offset = epos.offset;
462 }
463 }
464
465 if (count) {
466 /*
467 * NOTE: we CANNOT use udf_add_aext here, as it can try to
468 * allocate a new block, and since we hold the super block
469 * lock already very bad things would happen :)
470 *
471 * We copy the behavior of udf_add_aext, but instead of
472 * trying to allocate a new block close to the existing one,
473 * we just steal a block from the extent we are trying to add.
474 *
475 * It would be nice if the blocks were close together, but it
476 * isn't required.
477 */
478
479 int adsize;
480
481 eloc.logicalBlockNum = start;
482 elen = EXT_RECORDED_ALLOCATED |
483 (count << sb->s_blocksize_bits);
484
485 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
486 adsize = sizeof(struct short_ad);
487 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
488 adsize = sizeof(struct long_ad);
489 else {
490 brelse(oepos.bh);
491 brelse(epos.bh);
492 goto error_return;
493 }
494
495 if (epos.offset + (2 * adsize) > sb->s_blocksize) {
496 /* Steal a block from the extent being free'd */
497 udf_setup_indirect_aext(table, eloc.logicalBlockNum,
498 &epos);
499
500 eloc.logicalBlockNum++;
501 elen -= sb->s_blocksize;
502 }
503
504 /* It's possible that stealing the block emptied the extent */
505 if (elen)
506 __udf_add_aext(table, &epos, &eloc, elen, 1);
507 }
508
509 brelse(epos.bh);
510 brelse(oepos.bh);
511
512error_return:
513 mutex_unlock(&sbi->s_alloc_mutex);
514 return;
515}
516
517static int udf_table_prealloc_blocks(struct super_block *sb,
518 struct inode *table, uint16_t partition,
519 uint32_t first_block, uint32_t block_count)
520{
521 struct udf_sb_info *sbi = UDF_SB(sb);
522 int alloc_count = 0;
523 uint32_t elen, adsize;
524 struct kernel_lb_addr eloc;
525 struct extent_position epos;
526 int8_t etype = -1;
527 struct udf_inode_info *iinfo;
528
529 if (first_block >= sbi->s_partmaps[partition].s_partition_len)
530 return 0;
531
532 iinfo = UDF_I(table);
533 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
534 adsize = sizeof(struct short_ad);
535 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
536 adsize = sizeof(struct long_ad);
537 else
538 return 0;
539
540 mutex_lock(&sbi->s_alloc_mutex);
541 epos.offset = sizeof(struct unallocSpaceEntry);
542 epos.block = iinfo->i_location;
543 epos.bh = NULL;
544 eloc.logicalBlockNum = 0xFFFFFFFF;
545
546 while (first_block != eloc.logicalBlockNum &&
547 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
548 udf_debug("eloc=%u, elen=%u, first_block=%u\n",
549 eloc.logicalBlockNum, elen, first_block);
550 ; /* empty loop body */
551 }
552
553 if (first_block == eloc.logicalBlockNum) {
554 epos.offset -= adsize;
555
556 alloc_count = (elen >> sb->s_blocksize_bits);
557 if (alloc_count > block_count) {
558 alloc_count = block_count;
559 eloc.logicalBlockNum += alloc_count;
560 elen -= (alloc_count << sb->s_blocksize_bits);
561 udf_write_aext(table, &epos, &eloc,
562 (etype << 30) | elen, 1);
563 } else
564 udf_delete_aext(table, epos);
565 } else {
566 alloc_count = 0;
567 }
568
569 brelse(epos.bh);
570
571 if (alloc_count)
572 udf_add_free_space(sb, partition, -alloc_count);
573 mutex_unlock(&sbi->s_alloc_mutex);
574 return alloc_count;
575}
576
577static udf_pblk_t udf_table_new_block(struct super_block *sb,
578 struct inode *table, uint16_t partition,
579 uint32_t goal, int *err)
580{
581 struct udf_sb_info *sbi = UDF_SB(sb);
582 uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
583 udf_pblk_t newblock = 0;
584 uint32_t adsize;
585 uint32_t elen, goal_elen = 0;
586 struct kernel_lb_addr eloc, goal_eloc;
587 struct extent_position epos, goal_epos;
588 int8_t etype;
589 struct udf_inode_info *iinfo = UDF_I(table);
590
591 *err = -ENOSPC;
592
593 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
594 adsize = sizeof(struct short_ad);
595 else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
596 adsize = sizeof(struct long_ad);
597 else
598 return newblock;
599
600 mutex_lock(&sbi->s_alloc_mutex);
601 if (goal >= sbi->s_partmaps[partition].s_partition_len)
602 goal = 0;
603
604 /* We search for the closest matching block to goal. If we find
605 a exact hit, we stop. Otherwise we keep going till we run out
606 of extents. We store the buffer_head, bloc, and extoffset
607 of the current closest match and use that when we are done.
608 */
609 epos.offset = sizeof(struct unallocSpaceEntry);
610 epos.block = iinfo->i_location;
611 epos.bh = goal_epos.bh = NULL;
612
613 while (spread &&
614 (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
615 if (goal >= eloc.logicalBlockNum) {
616 if (goal < eloc.logicalBlockNum +
617 (elen >> sb->s_blocksize_bits))
618 nspread = 0;
619 else
620 nspread = goal - eloc.logicalBlockNum -
621 (elen >> sb->s_blocksize_bits);
622 } else {
623 nspread = eloc.logicalBlockNum - goal;
624 }
625
626 if (nspread < spread) {
627 spread = nspread;
628 if (goal_epos.bh != epos.bh) {
629 brelse(goal_epos.bh);
630 goal_epos.bh = epos.bh;
631 get_bh(goal_epos.bh);
632 }
633 goal_epos.block = epos.block;
634 goal_epos.offset = epos.offset - adsize;
635 goal_eloc = eloc;
636 goal_elen = (etype << 30) | elen;
637 }
638 }
639
640 brelse(epos.bh);
641
642 if (spread == 0xFFFFFFFF) {
643 brelse(goal_epos.bh);
644 mutex_unlock(&sbi->s_alloc_mutex);
645 return 0;
646 }
647
648 /* Only allocate blocks from the beginning of the extent.
649 That way, we only delete (empty) extents, never have to insert an
650 extent because of splitting */
651 /* This works, but very poorly.... */
652
653 newblock = goal_eloc.logicalBlockNum;
654 goal_eloc.logicalBlockNum++;
655 goal_elen -= sb->s_blocksize;
656
657 if (goal_elen)
658 udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1);
659 else
660 udf_delete_aext(table, goal_epos);
661 brelse(goal_epos.bh);
662
663 udf_add_free_space(sb, partition, -1);
664
665 mutex_unlock(&sbi->s_alloc_mutex);
666 *err = 0;
667 return newblock;
668}
669
670void udf_free_blocks(struct super_block *sb, struct inode *inode,
671 struct kernel_lb_addr *bloc, uint32_t offset,
672 uint32_t count)
673{
674 uint16_t partition = bloc->partitionReferenceNum;
675 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
676
677 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
678 udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap,
679 bloc, offset, count);
680 } else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
681 udf_table_free_blocks(sb, map->s_uspace.s_table,
682 bloc, offset, count);
683 }
684
685 if (inode) {
686 inode_sub_bytes(inode,
687 ((sector_t)count) << sb->s_blocksize_bits);
688 }
689}
690
691inline int udf_prealloc_blocks(struct super_block *sb,
692 struct inode *inode,
693 uint16_t partition, uint32_t first_block,
694 uint32_t block_count)
695{
696 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
697 int allocated;
698
699 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
700 allocated = udf_bitmap_prealloc_blocks(sb,
701 map->s_uspace.s_bitmap,
702 partition, first_block,
703 block_count);
704 else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
705 allocated = udf_table_prealloc_blocks(sb,
706 map->s_uspace.s_table,
707 partition, first_block,
708 block_count);
709 else
710 return 0;
711
712 if (inode && allocated > 0)
713 inode_add_bytes(inode, allocated << sb->s_blocksize_bits);
714 return allocated;
715}
716
717inline udf_pblk_t udf_new_block(struct super_block *sb,
718 struct inode *inode,
719 uint16_t partition, uint32_t goal, int *err)
720{
721 struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
722 udf_pblk_t block;
723
724 if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
725 block = udf_bitmap_new_block(sb,
726 map->s_uspace.s_bitmap,
727 partition, goal, err);
728 else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
729 block = udf_table_new_block(sb,
730 map->s_uspace.s_table,
731 partition, goal, err);
732 else {
733 *err = -EIO;
734 return 0;
735 }
736 if (inode && block)
737 inode_add_bytes(inode, sb->s_blocksize);
738 return block;
739}