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v6.13.7
  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#include <linux/overflow.h>
 22
 23#include "udf_i.h"
 24#include "udf_sb.h"
 25
 26#define udf_clear_bit	__test_and_clear_bit_le
 27#define udf_set_bit	__test_and_set_bit_le
 28#define udf_test_bit	test_bit_le
 29#define udf_find_next_one_bit	find_next_bit_le
 30
 31static int read_block_bitmap(struct super_block *sb,
 32			     struct udf_bitmap *bitmap, unsigned int block,
 33			     unsigned long bitmap_nr)
 34{
 35	struct buffer_head *bh = NULL;
 36	int i;
 37	int max_bits, off, count;
 38	struct kernel_lb_addr loc;
 39
 40	loc.logicalBlockNum = bitmap->s_extPosition;
 41	loc.partitionReferenceNum = UDF_SB(sb)->s_partition;
 42
 43	bh = sb_bread(sb, udf_get_lb_pblock(sb, &loc, block));
 44	bitmap->s_block_bitmap[bitmap_nr] = bh;
 45	if (!bh)
 46		return -EIO;
 47
 48	/* Check consistency of Space Bitmap buffer. */
 49	max_bits = sb->s_blocksize * 8;
 50	if (!bitmap_nr) {
 51		off = sizeof(struct spaceBitmapDesc) << 3;
 52		count = min(max_bits - off, bitmap->s_nr_groups);
 53	} else {
 54		/*
 55		 * Rough check if bitmap number is too big to have any bitmap
 56 		 * blocks reserved.
 57		 */
 58		if (bitmap_nr >
 59		    (bitmap->s_nr_groups >> (sb->s_blocksize_bits + 3)) + 2)
 60			return 0;
 61		off = 0;
 62		count = bitmap->s_nr_groups - bitmap_nr * max_bits +
 63				(sizeof(struct spaceBitmapDesc) << 3);
 64		count = min(count, max_bits);
 65	}
 66
 67	for (i = 0; i < count; i++)
 68		if (udf_test_bit(i + off, bh->b_data)) {
 69			bitmap->s_block_bitmap[bitmap_nr] =
 70							ERR_PTR(-EFSCORRUPTED);
 71			brelse(bh);
 72			return -EFSCORRUPTED;
 73		}
 74	return 0;
 75}
 76
 77static int load_block_bitmap(struct super_block *sb,
 78			     struct udf_bitmap *bitmap,
 79			     unsigned int block_group)
 80{
 81	int retval = 0;
 82	int nr_groups = bitmap->s_nr_groups;
 83
 84	if (block_group >= nr_groups) {
 85		udf_debug("block_group (%u) > nr_groups (%d)\n",
 86			  block_group, nr_groups);
 87	}
 88
 89	if (bitmap->s_block_bitmap[block_group]) {
 90		/*
 91		 * The bitmap failed verification in the past. No point in
 92		 * trying again.
 93		 */
 94		if (IS_ERR(bitmap->s_block_bitmap[block_group]))
 95			return PTR_ERR(bitmap->s_block_bitmap[block_group]);
 96		return block_group;
 97	}
 98
 99	retval = read_block_bitmap(sb, bitmap, block_group, block_group);
100	if (retval < 0)
101		return retval;
102
103	return block_group;
104}
105
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
106static void udf_add_free_space(struct super_block *sb, u16 partition, u32 cnt)
107{
108	struct udf_sb_info *sbi = UDF_SB(sb);
109	struct logicalVolIntegrityDesc *lvid;
110
111	if (!sbi->s_lvid_bh)
112		return;
113
114	lvid = (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data;
115	le32_add_cpu(&lvid->freeSpaceTable[partition], cnt);
116	udf_updated_lvid(sb);
117}
118
119static void udf_bitmap_free_blocks(struct super_block *sb,
120				   struct udf_bitmap *bitmap,
121				   struct kernel_lb_addr *bloc,
122				   uint32_t offset,
123				   uint32_t count)
124{
125	struct udf_sb_info *sbi = UDF_SB(sb);
126	struct buffer_head *bh = NULL;
 
127	unsigned long block;
128	unsigned long block_group;
129	unsigned long bit;
130	unsigned long i;
131	int bitmap_nr;
132	unsigned long overflow;
133
134	mutex_lock(&sbi->s_alloc_mutex);
135	/* We make sure this cannot overflow when mounting the filesystem */
 
 
 
 
 
 
 
 
 
136	block = bloc->logicalBlockNum + offset +
137		(sizeof(struct spaceBitmapDesc) << 3);
 
138	do {
139		overflow = 0;
140		block_group = block >> (sb->s_blocksize_bits + 3);
141		bit = block % (sb->s_blocksize << 3);
142
143		/*
144		* Check to see if we are freeing blocks across a group boundary.
145		*/
146		if (bit + count > (sb->s_blocksize << 3)) {
147			overflow = bit + count - (sb->s_blocksize << 3);
148			count -= overflow;
149		}
150		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
151		if (bitmap_nr < 0)
152			goto error_return;
153
154		bh = bitmap->s_block_bitmap[bitmap_nr];
155		for (i = 0; i < count; i++) {
156			if (udf_set_bit(bit + i, bh->b_data)) {
157				udf_debug("bit %lu already set\n", bit + i);
158				udf_debug("byte=%2x\n",
159					  ((__u8 *)bh->b_data)[(bit + i) >> 3]);
160			}
161		}
162		udf_add_free_space(sb, sbi->s_partition, count);
163		mark_buffer_dirty(bh);
164		if (overflow) {
165			block += count;
166			count = overflow;
167		}
168	} while (overflow);
169
170error_return:
171	mutex_unlock(&sbi->s_alloc_mutex);
172}
173
174static int udf_bitmap_prealloc_blocks(struct super_block *sb,
175				      struct udf_bitmap *bitmap,
176				      uint16_t partition, uint32_t first_block,
177				      uint32_t block_count)
178{
179	struct udf_sb_info *sbi = UDF_SB(sb);
180	int alloc_count = 0;
181	int bit, block, block_group;
182	int bitmap_nr;
183	struct buffer_head *bh;
184	__u32 part_len;
185
186	mutex_lock(&sbi->s_alloc_mutex);
187	part_len = sbi->s_partmaps[partition].s_partition_len;
188	if (first_block >= part_len)
189		goto out;
190
191	if (first_block + block_count > part_len)
192		block_count = part_len - first_block;
193
194	do {
195		block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
196		block_group = block >> (sb->s_blocksize_bits + 3);
197
198		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
199		if (bitmap_nr < 0)
200			goto out;
201		bh = bitmap->s_block_bitmap[bitmap_nr];
202
203		bit = block % (sb->s_blocksize << 3);
204
205		while (bit < (sb->s_blocksize << 3) && block_count > 0) {
206			if (!udf_clear_bit(bit, bh->b_data))
207				goto out;
208			block_count--;
209			alloc_count++;
210			bit++;
211			block++;
212		}
213		mark_buffer_dirty(bh);
214	} while (block_count > 0);
215
216out:
217	udf_add_free_space(sb, partition, -alloc_count);
218	mutex_unlock(&sbi->s_alloc_mutex);
219	return alloc_count;
220}
221
222static udf_pblk_t udf_bitmap_new_block(struct super_block *sb,
223				struct udf_bitmap *bitmap, uint16_t partition,
224				uint32_t goal, int *err)
225{
226	struct udf_sb_info *sbi = UDF_SB(sb);
227	int newbit, bit = 0;
228	udf_pblk_t block;
229	int block_group, group_start;
230	int end_goal, nr_groups, bitmap_nr, i;
231	struct buffer_head *bh = NULL;
232	char *ptr;
233	udf_pblk_t newblock = 0;
234
235	*err = -ENOSPC;
236	mutex_lock(&sbi->s_alloc_mutex);
237
238repeat:
239	if (goal >= sbi->s_partmaps[partition].s_partition_len)
240		goal = 0;
241
242	nr_groups = bitmap->s_nr_groups;
243	block = goal + (sizeof(struct spaceBitmapDesc) << 3);
244	block_group = block >> (sb->s_blocksize_bits + 3);
245	group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
246
247	bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
248	if (bitmap_nr < 0)
249		goto error_return;
250	bh = bitmap->s_block_bitmap[bitmap_nr];
251	ptr = memscan((char *)bh->b_data + group_start, 0xFF,
252		      sb->s_blocksize - group_start);
253
254	if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
255		bit = block % (sb->s_blocksize << 3);
256		if (udf_test_bit(bit, bh->b_data))
257			goto got_block;
258
259		end_goal = (bit + 63) & ~63;
260		bit = udf_find_next_one_bit(bh->b_data, end_goal, bit);
261		if (bit < end_goal)
262			goto got_block;
263
264		ptr = memscan((char *)bh->b_data + (bit >> 3), 0xFF,
265			      sb->s_blocksize - ((bit + 7) >> 3));
266		newbit = (ptr - ((char *)bh->b_data)) << 3;
267		if (newbit < sb->s_blocksize << 3) {
268			bit = newbit;
269			goto search_back;
270		}
271
272		newbit = udf_find_next_one_bit(bh->b_data,
273					       sb->s_blocksize << 3, bit);
274		if (newbit < sb->s_blocksize << 3) {
275			bit = newbit;
276			goto got_block;
277		}
278	}
279
280	for (i = 0; i < (nr_groups * 2); i++) {
281		block_group++;
282		if (block_group >= nr_groups)
283			block_group = 0;
284		group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
285
286		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
287		if (bitmap_nr < 0)
288			goto error_return;
289		bh = bitmap->s_block_bitmap[bitmap_nr];
290		if (i < nr_groups) {
291			ptr = memscan((char *)bh->b_data + group_start, 0xFF,
292				      sb->s_blocksize - group_start);
293			if ((ptr - ((char *)bh->b_data)) < sb->s_blocksize) {
294				bit = (ptr - ((char *)bh->b_data)) << 3;
295				break;
296			}
297		} else {
298			bit = udf_find_next_one_bit(bh->b_data,
299						    sb->s_blocksize << 3,
300						    group_start << 3);
301			if (bit < sb->s_blocksize << 3)
302				break;
303		}
304	}
305	if (i >= (nr_groups * 2)) {
306		mutex_unlock(&sbi->s_alloc_mutex);
307		return newblock;
308	}
309	if (bit < sb->s_blocksize << 3)
310		goto search_back;
311	else
312		bit = udf_find_next_one_bit(bh->b_data, sb->s_blocksize << 3,
313					    group_start << 3);
314	if (bit >= sb->s_blocksize << 3) {
315		mutex_unlock(&sbi->s_alloc_mutex);
316		return 0;
317	}
318
319search_back:
320	i = 0;
321	while (i < 7 && bit > (group_start << 3) &&
322	       udf_test_bit(bit - 1, bh->b_data)) {
323		++i;
324		--bit;
325	}
326
327got_block:
328	newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
329		(sizeof(struct spaceBitmapDesc) << 3);
330
331	if (newblock >= sbi->s_partmaps[partition].s_partition_len) {
332		/*
333		 * Ran off the end of the bitmap, and bits following are
334		 * non-compliant (not all zero)
335		 */
336		udf_err(sb, "bitmap for partition %d corrupted (block %u marked"
337			" as free, partition length is %u)\n", partition,
338			newblock, sbi->s_partmaps[partition].s_partition_len);
339		goto error_return;
340	}
341
342	if (!udf_clear_bit(bit, bh->b_data)) {
343		udf_debug("bit already cleared for block %d\n", bit);
344		goto repeat;
345	}
346
347	mark_buffer_dirty(bh);
348
349	udf_add_free_space(sb, partition, -1);
350	mutex_unlock(&sbi->s_alloc_mutex);
351	*err = 0;
352	return newblock;
353
354error_return:
355	*err = -EIO;
356	mutex_unlock(&sbi->s_alloc_mutex);
357	return 0;
358}
359
360static void udf_table_free_blocks(struct super_block *sb,
361				  struct inode *table,
362				  struct kernel_lb_addr *bloc,
363				  uint32_t offset,
364				  uint32_t count)
365{
366	struct udf_sb_info *sbi = UDF_SB(sb);
 
367	uint32_t start, end;
368	uint32_t elen;
369	struct kernel_lb_addr eloc;
370	struct extent_position oepos, epos;
371	int8_t etype;
372	struct udf_inode_info *iinfo;
373	int ret = 0;
374
375	mutex_lock(&sbi->s_alloc_mutex);
 
 
 
 
 
 
 
 
 
 
376	iinfo = UDF_I(table);
377	udf_add_free_space(sb, sbi->s_partition, count);
378
379	start = bloc->logicalBlockNum + offset;
380	end = bloc->logicalBlockNum + offset + count - 1;
381
382	epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry);
383	elen = 0;
384	epos.block = oepos.block = iinfo->i_location;
385	epos.bh = oepos.bh = NULL;
386
387	while (count) {
388		ret = udf_next_aext(table, &epos, &eloc, &elen, &etype, 1);
389		if (ret < 0)
390			goto error_return;
391		if (ret == 0)
392			break;
393		if (((eloc.logicalBlockNum +
394			(elen >> sb->s_blocksize_bits)) == start)) {
395			if ((0x3FFFFFFF - elen) <
396					(count << sb->s_blocksize_bits)) {
397				uint32_t tmp = ((0x3FFFFFFF - elen) >>
398							sb->s_blocksize_bits);
399				count -= tmp;
400				start += tmp;
401				elen = (etype << 30) |
402					(0x40000000 - sb->s_blocksize);
403			} else {
404				elen = (etype << 30) |
405					(elen +
406					(count << sb->s_blocksize_bits));
407				start += count;
408				count = 0;
409			}
410			udf_write_aext(table, &oepos, &eloc, elen, 1);
411		} else if (eloc.logicalBlockNum == (end + 1)) {
412			if ((0x3FFFFFFF - elen) <
413					(count << sb->s_blocksize_bits)) {
414				uint32_t tmp = ((0x3FFFFFFF - elen) >>
415						sb->s_blocksize_bits);
416				count -= tmp;
417				end -= tmp;
418				eloc.logicalBlockNum -= tmp;
419				elen = (etype << 30) |
420					(0x40000000 - sb->s_blocksize);
421			} else {
422				eloc.logicalBlockNum = start;
423				elen = (etype << 30) |
424					(elen +
425					(count << sb->s_blocksize_bits));
426				end -= count;
427				count = 0;
428			}
429			udf_write_aext(table, &oepos, &eloc, elen, 1);
430		}
431
432		if (epos.bh != oepos.bh) {
433			oepos.block = epos.block;
434			brelse(oepos.bh);
435			get_bh(epos.bh);
436			oepos.bh = epos.bh;
437			oepos.offset = 0;
438		} else {
439			oepos.offset = epos.offset;
440		}
441	}
442
443	if (count) {
444		/*
445		 * NOTE: we CANNOT use udf_add_aext here, as it can try to
446		 * allocate a new block, and since we hold the super block
447		 * lock already very bad things would happen :)
448		 *
449		 * We copy the behavior of udf_add_aext, but instead of
450		 * trying to allocate a new block close to the existing one,
451		 * we just steal a block from the extent we are trying to add.
452		 *
453		 * It would be nice if the blocks were close together, but it
454		 * isn't required.
455		 */
456
457		int adsize;
458
459		eloc.logicalBlockNum = start;
460		elen = EXT_RECORDED_ALLOCATED |
461			(count << sb->s_blocksize_bits);
462
463		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
464			adsize = sizeof(struct short_ad);
465		else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
466			adsize = sizeof(struct long_ad);
467		else
 
 
468			goto error_return;
 
469
470		if (epos.offset + (2 * adsize) > sb->s_blocksize) {
471			/* Steal a block from the extent being free'd */
472			udf_setup_indirect_aext(table, eloc.logicalBlockNum,
473						&epos);
474
475			eloc.logicalBlockNum++;
476			elen -= sb->s_blocksize;
477		}
478
479		/* It's possible that stealing the block emptied the extent */
480		if (elen)
481			__udf_add_aext(table, &epos, &eloc, elen, 1);
482	}
483
484error_return:
485	brelse(epos.bh);
486	brelse(oepos.bh);
487
 
488	mutex_unlock(&sbi->s_alloc_mutex);
489	return;
490}
491
492static int udf_table_prealloc_blocks(struct super_block *sb,
493				     struct inode *table, uint16_t partition,
494				     uint32_t first_block, uint32_t block_count)
495{
496	struct udf_sb_info *sbi = UDF_SB(sb);
497	int alloc_count = 0;
498	uint32_t elen, adsize;
499	struct kernel_lb_addr eloc;
500	struct extent_position epos;
501	int8_t etype = -1;
502	struct udf_inode_info *iinfo;
503	int ret = 0;
504
505	if (first_block >= sbi->s_partmaps[partition].s_partition_len)
506		return 0;
507
508	iinfo = UDF_I(table);
509	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
510		adsize = sizeof(struct short_ad);
511	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
512		adsize = sizeof(struct long_ad);
513	else
514		return 0;
515
516	mutex_lock(&sbi->s_alloc_mutex);
517	epos.offset = sizeof(struct unallocSpaceEntry);
518	epos.block = iinfo->i_location;
519	epos.bh = NULL;
520	eloc.logicalBlockNum = 0xFFFFFFFF;
521
522	while (first_block != eloc.logicalBlockNum) {
523		ret = udf_next_aext(table, &epos, &eloc, &elen, &etype, 1);
524		if (ret < 0)
525			goto err_out;
526		if (ret == 0)
527			break;
528		udf_debug("eloc=%u, elen=%u, first_block=%u\n",
529			  eloc.logicalBlockNum, elen, first_block);
 
530	}
531
532	if (first_block == eloc.logicalBlockNum) {
533		epos.offset -= adsize;
534
535		alloc_count = (elen >> sb->s_blocksize_bits);
536		if (alloc_count > block_count) {
537			alloc_count = block_count;
538			eloc.logicalBlockNum += alloc_count;
539			elen -= (alloc_count << sb->s_blocksize_bits);
540			udf_write_aext(table, &epos, &eloc,
541					(etype << 30) | elen, 1);
542		} else
543			udf_delete_aext(table, epos);
544	} else {
545		alloc_count = 0;
546	}
547
548err_out:
549	brelse(epos.bh);
550
551	if (alloc_count)
552		udf_add_free_space(sb, partition, -alloc_count);
553	mutex_unlock(&sbi->s_alloc_mutex);
554	return alloc_count;
555}
556
557static udf_pblk_t udf_table_new_block(struct super_block *sb,
558			       struct inode *table, uint16_t partition,
559			       uint32_t goal, int *err)
560{
561	struct udf_sb_info *sbi = UDF_SB(sb);
562	uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
563	udf_pblk_t newblock = 0;
564	uint32_t adsize;
565	uint32_t elen, goal_elen = 0;
566	struct kernel_lb_addr eloc, goal_eloc;
567	struct extent_position epos, goal_epos;
568	int8_t etype;
569	struct udf_inode_info *iinfo = UDF_I(table);
570	int ret = 0;
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		ret = udf_next_aext(table, &epos, &eloc, &elen, &etype, 1);
596		if (ret <= 0)
597			break;
598		if (goal >= eloc.logicalBlockNum) {
599			if (goal < eloc.logicalBlockNum +
600					(elen >> sb->s_blocksize_bits))
601				nspread = 0;
602			else
603				nspread = goal - eloc.logicalBlockNum -
604					(elen >> sb->s_blocksize_bits);
605		} else {
606			nspread = eloc.logicalBlockNum - goal;
607		}
608
609		if (nspread < spread) {
610			spread = nspread;
611			if (goal_epos.bh != epos.bh) {
612				brelse(goal_epos.bh);
613				goal_epos.bh = epos.bh;
614				get_bh(goal_epos.bh);
615			}
616			goal_epos.block = epos.block;
617			goal_epos.offset = epos.offset - adsize;
618			goal_eloc = eloc;
619			goal_elen = (etype << 30) | elen;
620		}
621	}
622
623	brelse(epos.bh);
624
625	if (ret < 0 || spread == 0xFFFFFFFF) {
626		brelse(goal_epos.bh);
627		mutex_unlock(&sbi->s_alloc_mutex);
628		if (ret < 0)
629			*err = ret;
630		return 0;
631	}
632
633	/* Only allocate blocks from the beginning of the extent.
634	   That way, we only delete (empty) extents, never have to insert an
635	   extent because of splitting */
636	/* This works, but very poorly.... */
637
638	newblock = goal_eloc.logicalBlockNum;
639	goal_eloc.logicalBlockNum++;
640	goal_elen -= sb->s_blocksize;
641
642	if (goal_elen)
643		udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1);
644	else
645		udf_delete_aext(table, goal_epos);
646	brelse(goal_epos.bh);
647
648	udf_add_free_space(sb, partition, -1);
649
650	mutex_unlock(&sbi->s_alloc_mutex);
651	*err = 0;
652	return newblock;
653}
654
655void udf_free_blocks(struct super_block *sb, struct inode *inode,
656		     struct kernel_lb_addr *bloc, uint32_t offset,
657		     uint32_t count)
658{
659	uint16_t partition = bloc->partitionReferenceNum;
660	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
661	uint32_t blk;
662
663	if (check_add_overflow(bloc->logicalBlockNum, offset, &blk) ||
664	    check_add_overflow(blk, count, &blk) ||
665	    bloc->logicalBlockNum + count > map->s_partition_len) {
666		udf_debug("Invalid request to free blocks: (%d, %u), off %u, "
667			  "len %u, partition len %u\n",
668			  partition, bloc->logicalBlockNum, offset, count,
669			  map->s_partition_len);
670		return;
671	}
672
673	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
674		udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap,
675				       bloc, offset, count);
676	} else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
677		udf_table_free_blocks(sb, map->s_uspace.s_table,
678				      bloc, offset, count);
679	}
680
681	if (inode) {
682		inode_sub_bytes(inode,
683				((sector_t)count) << sb->s_blocksize_bits);
684	}
685}
686
687inline int udf_prealloc_blocks(struct super_block *sb,
688			       struct inode *inode,
689			       uint16_t partition, uint32_t first_block,
690			       uint32_t block_count)
691{
692	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
693	int allocated;
694
695	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
696		allocated = udf_bitmap_prealloc_blocks(sb,
697						       map->s_uspace.s_bitmap,
698						       partition, first_block,
699						       block_count);
700	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
701		allocated = udf_table_prealloc_blocks(sb,
702						      map->s_uspace.s_table,
703						      partition, first_block,
704						      block_count);
705	else
706		return 0;
707
708	if (inode && allocated > 0)
709		inode_add_bytes(inode, allocated << sb->s_blocksize_bits);
710	return allocated;
711}
712
713inline udf_pblk_t udf_new_block(struct super_block *sb,
714			 struct inode *inode,
715			 uint16_t partition, uint32_t goal, int *err)
716{
717	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
718	udf_pblk_t block;
719
720	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
721		block = udf_bitmap_new_block(sb,
722					     map->s_uspace.s_bitmap,
723					     partition, goal, err);
724	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
725		block = udf_table_new_block(sb,
726					    map->s_uspace.s_table,
727					    partition, goal, err);
728	else {
729		*err = -EIO;
730		return 0;
731	}
732	if (inode && block)
733		inode_add_bytes(inode, sb->s_blocksize);
734	return block;
735}
v6.8
  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}