xref: /openbmc/linux/fs/udf/balloc.c (revision 3e30a927)
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/bitops.h>
25 
26 #include "udf_i.h"
27 #include "udf_sb.h"
28 
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
33 
34 static int read_block_bitmap(struct super_block *sb,
35 			     struct udf_bitmap *bitmap, unsigned int block,
36 			     unsigned long bitmap_nr)
37 {
38 	struct buffer_head *bh = NULL;
39 	int retval = 0;
40 	struct kernel_lb_addr loc;
41 
42 	loc.logicalBlockNum = bitmap->s_extPosition;
43 	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
44 
45 	bh = udf_tread(sb, udf_get_lb_pblock(sb, &loc, block));
46 	if (!bh)
47 		retval = -EIO;
48 
49 	bitmap->s_block_bitmap[bitmap_nr] = bh;
50 	return retval;
51 }
52 
53 static int __load_block_bitmap(struct super_block *sb,
54 			       struct udf_bitmap *bitmap,
55 			       unsigned int block_group)
56 {
57 	int retval = 0;
58 	int nr_groups = bitmap->s_nr_groups;
59 
60 	if (block_group >= nr_groups) {
61 		udf_debug("block_group (%u) > nr_groups (%d)\n",
62 			  block_group, nr_groups);
63 	}
64 
65 	if (bitmap->s_block_bitmap[block_group])
66 		return block_group;
67 
68 	retval = read_block_bitmap(sb, bitmap, block_group, block_group);
69 	if (retval < 0)
70 		return retval;
71 
72 	return block_group;
73 }
74 
75 static inline int load_block_bitmap(struct super_block *sb,
76 				    struct udf_bitmap *bitmap,
77 				    unsigned int block_group)
78 {
79 	int slot;
80 
81 	slot = __load_block_bitmap(sb, bitmap, block_group);
82 
83 	if (slot < 0)
84 		return slot;
85 
86 	if (!bitmap->s_block_bitmap[slot])
87 		return -EIO;
88 
89 	return slot;
90 }
91 
92 static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt)
93 {
94 	struct udf_sb_info *sbi = UDF_SB(sb);
95 	struct logicalVolIntegrityDesc *lvid;
96 
97 	if (!sbi->s_lvid_bh)
98 		return;
99 
100 	lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data;
101 	le32_add_cpu(&lvid->freeSpaceTable[partition], cnt);
102 	udf_updated_lvid(sb);
103 }
104 
105 static void udf_bitmap_free_blocks(struct super_block *sb,
106 				   struct udf_bitmap *bitmap,
107 				   struct kernel_lb_addr *bloc,
108 				   uint32_t offset,
109 				   uint32_t count)
110 {
111 	struct udf_sb_info *sbi = UDF_SB(sb);
112 	struct buffer_head *bh = NULL;
113 	struct udf_part_map *partmap;
114 	unsigned long block;
115 	unsigned long block_group;
116 	unsigned long bit;
117 	unsigned long i;
118 	int bitmap_nr;
119 	unsigned long overflow;
120 
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);
129 		goto error_return;
130 	}
131 
132 	block = bloc->logicalBlockNum + offset +
133 		(sizeof(struct spaceBitmapDesc) << 3);
134 
135 	do {
136 		overflow = 0;
137 		block_group = block >> (sb->s_blocksize_bits + 3);
138 		bit = block % (sb->s_blocksize << 3);
139 
140 		/*
141 		* Check to see if we are freeing blocks across a group boundary.
142 		*/
143 		if (bit + count > (sb->s_blocksize << 3)) {
144 			overflow = bit + count - (sb->s_blocksize << 3);
145 			count -= overflow;
146 		}
147 		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
148 		if (bitmap_nr < 0)
149 			goto error_return;
150 
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]);
157 			}
158 		}
159 		udf_add_free_space(sb, sbi->s_partition, count);
160 		mark_buffer_dirty(bh);
161 		if (overflow) {
162 			block += count;
163 			count = overflow;
164 		}
165 	} while (overflow);
166 
167 error_return:
168 	mutex_unlock(&sbi->s_alloc_mutex);
169 }
170 
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)
175 {
176 	struct udf_sb_info *sbi = UDF_SB(sb);
177 	int alloc_count = 0;
178 	int bit, block, block_group;
179 	int bitmap_nr;
180 	struct buffer_head *bh;
181 	__u32 part_len;
182 
183 	mutex_lock(&sbi->s_alloc_mutex);
184 	part_len = sbi->s_partmaps[partition].s_partition_len;
185 	if (first_block >= part_len)
186 		goto out;
187 
188 	if (first_block + block_count > part_len)
189 		block_count = part_len - first_block;
190 
191 	do {
192 		block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
193 		block_group = block >> (sb->s_blocksize_bits + 3);
194 
195 		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
196 		if (bitmap_nr < 0)
197 			goto out;
198 		bh = bitmap->s_block_bitmap[bitmap_nr];
199 
200 		bit = block % (sb->s_blocksize << 3);
201 
202 		while (bit < (sb->s_blocksize << 3) && block_count > 0) {
203 			if (!udf_clear_bit(bit, bh->b_data))
204 				goto out;
205 			block_count--;
206 			alloc_count++;
207 			bit++;
208 			block++;
209 		}
210 		mark_buffer_dirty(bh);
211 	} while (block_count > 0);
212 
213 out:
214 	udf_add_free_space(sb, partition, -alloc_count);
215 	mutex_unlock(&sbi->s_alloc_mutex);
216 	return alloc_count;
217 }
218 
219 static udf_pblk_t udf_bitmap_new_block(struct super_block *sb,
220 				struct udf_bitmap *bitmap, uint16_t partition,
221 				uint32_t goal, int *err)
222 {
223 	struct udf_sb_info *sbi = UDF_SB(sb);
224 	int newbit, bit = 0;
225 	udf_pblk_t block;
226 	int block_group, group_start;
227 	int end_goal, nr_groups, bitmap_nr, i;
228 	struct buffer_head *bh = NULL;
229 	char *ptr;
230 	udf_pblk_t newblock = 0;
231 
232 	*err = -ENOSPC;
233 	mutex_lock(&sbi->s_alloc_mutex);
234 
235 repeat:
236 	if (goal >= sbi->s_partmaps[partition].s_partition_len)
237 		goal = 0;
238 
239 	nr_groups = bitmap->s_nr_groups;
240 	block = goal + (sizeof(struct spaceBitmapDesc) << 3);
241 	block_group = block >> (sb->s_blocksize_bits + 3);
242 	group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
243 
244 	bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
245 	if (bitmap_nr < 0)
246 		goto error_return;
247 	bh = bitmap->s_block_bitmap[bitmap_nr];
248 	ptr = memscan((char *)bh->b_data + group_start, 0xFF,
249 		      sb->s_blocksize - group_start);
250 
251 	if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
252 		bit = block % (sb->s_blocksize << 3);
253 		if (udf_test_bit(bit, bh->b_data))
254 			goto got_block;
255 
256 		end_goal = (bit + 63) & ~63;
257 		bit = udf_find_next_one_bit(bh->b_data, end_goal, bit);
258 		if (bit < end_goal)
259 			goto got_block;
260 
261 		ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF,
262 			      sb->s_blocksize - ((bit + 7) >> 3));
263 		newbit = (ptr - ((char *)bh->b_data)) << 3;
264 		if (newbit < sb->s_blocksize << 3) {
265 			bit = newbit;
266 			goto search_back;
267 		}
268 
269 		newbit = udf_find_next_one_bit(bh->b_data,
270 					       sb->s_blocksize << 3, bit);
271 		if (newbit < sb->s_blocksize << 3) {
272 			bit = newbit;
273 			goto got_block;
274 		}
275 	}
276 
277 	for (i = 0; i < (nr_groups * 2); i++) {
278 		block_group++;
279 		if (block_group >= nr_groups)
280 			block_group = 0;
281 		group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
282 
283 		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
284 		if (bitmap_nr < 0)
285 			goto error_return;
286 		bh = bitmap->s_block_bitmap[bitmap_nr];
287 		if (i < nr_groups) {
288 			ptr = memscan((char *)bh->b_data + group_start, 0xFF,
289 				      sb->s_blocksize - group_start);
290 			if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
291 				bit = (ptr - ((char *)bh->b_data)) << 3;
292 				break;
293 			}
294 		} else {
295 			bit = udf_find_next_one_bit(bh->b_data,
296 						    sb->s_blocksize << 3,
297 						    group_start << 3);
298 			if (bit < sb->s_blocksize << 3)
299 				break;
300 		}
301 	}
302 	if (i >= (nr_groups * 2)) {
303 		mutex_unlock(&sbi->s_alloc_mutex);
304 		return newblock;
305 	}
306 	if (bit < sb->s_blocksize << 3)
307 		goto search_back;
308 	else
309 		bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3,
310 					    group_start << 3);
311 	if (bit >= sb->s_blocksize << 3) {
312 		mutex_unlock(&sbi->s_alloc_mutex);
313 		return 0;
314 	}
315 
316 search_back:
317 	i = 0;
318 	while (i < 7 && bit > (group_start << 3) &&
319 	       udf_test_bit(bit - 1, bh->b_data)) {
320 		++i;
321 		--bit;
322 	}
323 
324 got_block:
325 	newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
326 		(sizeof(struct spaceBitmapDesc) << 3);
327 
328 	if (newblock >= sbi->s_partmaps[partition].s_partition_len) {
329 		/*
330 		 * Ran off the end of the bitmap, and bits following are
331 		 * non-compliant (not all zero)
332 		 */
333 		udf_err(sb, "bitmap for partition %d corrupted (block %u marked"
334 			" as free, partition length is %u)\n", partition,
335 			newblock, sbi->s_partmaps[partition].s_partition_len);
336 		goto error_return;
337 	}
338 
339 	if (!udf_clear_bit(bit, bh->b_data)) {
340 		udf_debug("bit already cleared for block %d\n", bit);
341 		goto repeat;
342 	}
343 
344 	mark_buffer_dirty(bh);
345 
346 	udf_add_free_space(sb, partition, -1);
347 	mutex_unlock(&sbi->s_alloc_mutex);
348 	*err = 0;
349 	return newblock;
350 
351 error_return:
352 	*err = -EIO;
353 	mutex_unlock(&sbi->s_alloc_mutex);
354 	return 0;
355 }
356 
357 static void udf_table_free_blocks(struct super_block *sb,
358 				  struct inode *table,
359 				  struct kernel_lb_addr *bloc,
360 				  uint32_t offset,
361 				  uint32_t count)
362 {
363 	struct udf_sb_info *sbi = UDF_SB(sb);
364 	struct udf_part_map *partmap;
365 	uint32_t start, end;
366 	uint32_t elen;
367 	struct kernel_lb_addr eloc;
368 	struct extent_position oepos, epos;
369 	int8_t etype;
370 	struct udf_inode_info *iinfo;
371 
372 	mutex_lock(&sbi->s_alloc_mutex);
373 	partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
374 	if (bloc->logicalBlockNum + count < count ||
375 	    (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
376 		udf_debug("%u < %d || %u + %u > %u\n",
377 			  bloc->logicalBlockNum, 0,
378 			  bloc->logicalBlockNum, count,
379 			  partmap->s_partition_len);
380 		goto error_return;
381 	}
382 
383 	iinfo = UDF_I(table);
384 	udf_add_free_space(sb, sbi->s_partition, count);
385 
386 	start = bloc->logicalBlockNum + offset;
387 	end = bloc->logicalBlockNum + offset + count - 1;
388 
389 	epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry);
390 	elen = 0;
391 	epos.block = oepos.block = iinfo->i_location;
392 	epos.bh = oepos.bh = NULL;
393 
394 	while (count &&
395 	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
396 		if (((eloc.logicalBlockNum +
397 			(elen >> sb->s_blocksize_bits)) == start)) {
398 			if ((0x3FFFFFFF - elen) <
399 					(count << sb->s_blocksize_bits)) {
400 				uint32_t tmp = ((0x3FFFFFFF - elen) >>
401 							sb->s_blocksize_bits);
402 				count -= tmp;
403 				start += tmp;
404 				elen = (etype << 30) |
405 					(0x40000000 - sb->s_blocksize);
406 			} else {
407 				elen = (etype << 30) |
408 					(elen +
409 					(count << sb->s_blocksize_bits));
410 				start += count;
411 				count = 0;
412 			}
413 			udf_write_aext(table, &oepos, &eloc, elen, 1);
414 		} else if (eloc.logicalBlockNum == (end + 1)) {
415 			if ((0x3FFFFFFF - elen) <
416 					(count << sb->s_blocksize_bits)) {
417 				uint32_t tmp = ((0x3FFFFFFF - elen) >>
418 						sb->s_blocksize_bits);
419 				count -= tmp;
420 				end -= tmp;
421 				eloc.logicalBlockNum -= tmp;
422 				elen = (etype << 30) |
423 					(0x40000000 - sb->s_blocksize);
424 			} else {
425 				eloc.logicalBlockNum = start;
426 				elen = (etype << 30) |
427 					(elen +
428 					(count << sb->s_blocksize_bits));
429 				end -= count;
430 				count = 0;
431 			}
432 			udf_write_aext(table, &oepos, &eloc, elen, 1);
433 		}
434 
435 		if (epos.bh != oepos.bh) {
436 			oepos.block = epos.block;
437 			brelse(oepos.bh);
438 			get_bh(epos.bh);
439 			oepos.bh = epos.bh;
440 			oepos.offset = 0;
441 		} else {
442 			oepos.offset = epos.offset;
443 		}
444 	}
445 
446 	if (count) {
447 		/*
448 		 * NOTE: we CANNOT use udf_add_aext here, as it can try to
449 		 * allocate a new block, and since we hold the super block
450 		 * lock already very bad things would happen :)
451 		 *
452 		 * We copy the behavior of udf_add_aext, but instead of
453 		 * trying to allocate a new block close to the existing one,
454 		 * we just steal a block from the extent we are trying to add.
455 		 *
456 		 * It would be nice if the blocks were close together, but it
457 		 * isn't required.
458 		 */
459 
460 		int adsize;
461 
462 		eloc.logicalBlockNum = start;
463 		elen = EXT_RECORDED_ALLOCATED |
464 			(count << sb->s_blocksize_bits);
465 
466 		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
467 			adsize = sizeof(struct short_ad);
468 		else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
469 			adsize = sizeof(struct long_ad);
470 		else {
471 			brelse(oepos.bh);
472 			brelse(epos.bh);
473 			goto error_return;
474 		}
475 
476 		if (epos.offset + (2 * adsize) > sb->s_blocksize) {
477 			/* Steal a block from the extent being free'd */
478 			udf_setup_indirect_aext(table, eloc.logicalBlockNum,
479 						&epos);
480 
481 			eloc.logicalBlockNum++;
482 			elen -= sb->s_blocksize;
483 		}
484 
485 		/* It's possible that stealing the block emptied the extent */
486 		if (elen)
487 			__udf_add_aext(table, &epos, &eloc, elen, 1);
488 	}
489 
490 	brelse(epos.bh);
491 	brelse(oepos.bh);
492 
493 error_return:
494 	mutex_unlock(&sbi->s_alloc_mutex);
495 	return;
496 }
497 
498 static int udf_table_prealloc_blocks(struct super_block *sb,
499 				     struct inode *table, uint16_t partition,
500 				     uint32_t first_block, uint32_t block_count)
501 {
502 	struct udf_sb_info *sbi = UDF_SB(sb);
503 	int alloc_count = 0;
504 	uint32_t elen, adsize;
505 	struct kernel_lb_addr eloc;
506 	struct extent_position epos;
507 	int8_t etype = -1;
508 	struct udf_inode_info *iinfo;
509 
510 	if (first_block >= sbi->s_partmaps[partition].s_partition_len)
511 		return 0;
512 
513 	iinfo = UDF_I(table);
514 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
515 		adsize = sizeof(struct short_ad);
516 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
517 		adsize = sizeof(struct long_ad);
518 	else
519 		return 0;
520 
521 	mutex_lock(&sbi->s_alloc_mutex);
522 	epos.offset = sizeof(struct unallocSpaceEntry);
523 	epos.block = iinfo->i_location;
524 	epos.bh = NULL;
525 	eloc.logicalBlockNum = 0xFFFFFFFF;
526 
527 	while (first_block != eloc.logicalBlockNum &&
528 	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
529 		udf_debug("eloc=%u, elen=%u, first_block=%u\n",
530 			  eloc.logicalBlockNum, elen, first_block);
531 		; /* empty loop body */
532 	}
533 
534 	if (first_block == eloc.logicalBlockNum) {
535 		epos.offset -= adsize;
536 
537 		alloc_count = (elen >> sb->s_blocksize_bits);
538 		if (alloc_count > block_count) {
539 			alloc_count = block_count;
540 			eloc.logicalBlockNum += alloc_count;
541 			elen -= (alloc_count << sb->s_blocksize_bits);
542 			udf_write_aext(table, &epos, &eloc,
543 					(etype << 30) | elen, 1);
544 		} else
545 			udf_delete_aext(table, epos);
546 	} else {
547 		alloc_count = 0;
548 	}
549 
550 	brelse(epos.bh);
551 
552 	if (alloc_count)
553 		udf_add_free_space(sb, partition, -alloc_count);
554 	mutex_unlock(&sbi->s_alloc_mutex);
555 	return alloc_count;
556 }
557 
558 static udf_pblk_t udf_table_new_block(struct super_block *sb,
559 			       struct inode *table, uint16_t partition,
560 			       uint32_t goal, int *err)
561 {
562 	struct udf_sb_info *sbi = UDF_SB(sb);
563 	uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
564 	udf_pblk_t newblock = 0;
565 	uint32_t adsize;
566 	uint32_t elen, goal_elen = 0;
567 	struct kernel_lb_addr eloc, uninitialized_var(goal_eloc);
568 	struct extent_position epos, goal_epos;
569 	int8_t etype;
570 	struct udf_inode_info *iinfo = UDF_I(table);
571 
572 	*err = -ENOSPC;
573 
574 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
575 		adsize = sizeof(struct short_ad);
576 	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
577 		adsize = sizeof(struct long_ad);
578 	else
579 		return newblock;
580 
581 	mutex_lock(&sbi->s_alloc_mutex);
582 	if (goal >= sbi->s_partmaps[partition].s_partition_len)
583 		goal = 0;
584 
585 	/* We search for the closest matching block to goal. If we find
586 	   a exact hit, we stop. Otherwise we keep going till we run out
587 	   of extents. We store the buffer_head, bloc, and extoffset
588 	   of the current closest match and use that when we are done.
589 	 */
590 	epos.offset = sizeof(struct unallocSpaceEntry);
591 	epos.block = iinfo->i_location;
592 	epos.bh = goal_epos.bh = NULL;
593 
594 	while (spread &&
595 	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
596 		if (goal >= eloc.logicalBlockNum) {
597 			if (goal < eloc.logicalBlockNum +
598 					(elen >> sb->s_blocksize_bits))
599 				nspread = 0;
600 			else
601 				nspread = goal - eloc.logicalBlockNum -
602 					(elen >> sb->s_blocksize_bits);
603 		} else {
604 			nspread = eloc.logicalBlockNum - goal;
605 		}
606 
607 		if (nspread < spread) {
608 			spread = nspread;
609 			if (goal_epos.bh != epos.bh) {
610 				brelse(goal_epos.bh);
611 				goal_epos.bh = epos.bh;
612 				get_bh(goal_epos.bh);
613 			}
614 			goal_epos.block = epos.block;
615 			goal_epos.offset = epos.offset - adsize;
616 			goal_eloc = eloc;
617 			goal_elen = (etype << 30) | elen;
618 		}
619 	}
620 
621 	brelse(epos.bh);
622 
623 	if (spread == 0xFFFFFFFF) {
624 		brelse(goal_epos.bh);
625 		mutex_unlock(&sbi->s_alloc_mutex);
626 		return 0;
627 	}
628 
629 	/* Only allocate blocks from the beginning of the extent.
630 	   That way, we only delete (empty) extents, never have to insert an
631 	   extent because of splitting */
632 	/* This works, but very poorly.... */
633 
634 	newblock = goal_eloc.logicalBlockNum;
635 	goal_eloc.logicalBlockNum++;
636 	goal_elen -= sb->s_blocksize;
637 
638 	if (goal_elen)
639 		udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1);
640 	else
641 		udf_delete_aext(table, goal_epos);
642 	brelse(goal_epos.bh);
643 
644 	udf_add_free_space(sb, partition, -1);
645 
646 	mutex_unlock(&sbi->s_alloc_mutex);
647 	*err = 0;
648 	return newblock;
649 }
650 
651 void udf_free_blocks(struct super_block *sb, struct inode *inode,
652 		     struct kernel_lb_addr *bloc, uint32_t offset,
653 		     uint32_t count)
654 {
655 	uint16_t partition = bloc->partitionReferenceNum;
656 	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
657 
658 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
659 		udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap,
660 				       bloc, offset, count);
661 	} else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
662 		udf_table_free_blocks(sb, map->s_uspace.s_table,
663 				      bloc, offset, count);
664 	}
665 
666 	if (inode) {
667 		inode_sub_bytes(inode,
668 				((sector_t)count) << sb->s_blocksize_bits);
669 	}
670 }
671 
672 inline int udf_prealloc_blocks(struct super_block *sb,
673 			       struct inode *inode,
674 			       uint16_t partition, uint32_t first_block,
675 			       uint32_t block_count)
676 {
677 	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
678 	int allocated;
679 
680 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
681 		allocated = udf_bitmap_prealloc_blocks(sb,
682 						       map->s_uspace.s_bitmap,
683 						       partition, first_block,
684 						       block_count);
685 	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
686 		allocated = udf_table_prealloc_blocks(sb,
687 						      map->s_uspace.s_table,
688 						      partition, first_block,
689 						      block_count);
690 	else
691 		return 0;
692 
693 	if (inode && allocated > 0)
694 		inode_add_bytes(inode, allocated << sb->s_blocksize_bits);
695 	return allocated;
696 }
697 
698 inline udf_pblk_t udf_new_block(struct super_block *sb,
699 			 struct inode *inode,
700 			 uint16_t partition, uint32_t goal, int *err)
701 {
702 	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
703 	udf_pblk_t block;
704 
705 	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
706 		block = udf_bitmap_new_block(sb,
707 					     map->s_uspace.s_bitmap,
708 					     partition, goal, err);
709 	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
710 		block = udf_table_new_block(sb,
711 					    map->s_uspace.s_table,
712 					    partition, goal, err);
713 	else {
714 		*err = -EIO;
715 		return 0;
716 	}
717 	if (inode && block)
718 		inode_add_bytes(inode, sb->s_blocksize);
719 	return block;
720 }
721