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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}
v4.6
 
  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
 34static 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
 53static 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 (%d) > 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
 75static 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
 92static 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
105static 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("%d < %d || %d + %d > %d\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 %ld already set\n", bit + i);
155				udf_debug("byte=%2x\n",
156					  ((char *)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
167error_return:
168	mutex_unlock(&sbi->s_alloc_mutex);
169}
170
171static 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, group_start;
179	int nr_groups, 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		nr_groups = udf_compute_nr_groups(sb, partition);
193		block = first_block + (sizeof(struct spaceBitmapDesc) << 3);
194		block_group = block >> (sb->s_blocksize_bits + 3);
195		group_start = block_group ? 0 : sizeof(struct spaceBitmapDesc);
196
197		bitmap_nr = load_block_bitmap(sb, bitmap, block_group);
198		if (bitmap_nr < 0)
199			goto out;
200		bh = bitmap->s_block_bitmap[bitmap_nr];
201
202		bit = block % (sb->s_blocksize << 3);
203
204		while (bit < (sb->s_blocksize << 3) && block_count > 0) {
205			if (!udf_clear_bit(bit, bh->b_data))
206				goto out;
207			block_count--;
208			alloc_count++;
209			bit++;
210			block++;
211		}
212		mark_buffer_dirty(bh);
213	} while (block_count > 0);
214
215out:
216	udf_add_free_space(sb, partition, -alloc_count);
217	mutex_unlock(&sbi->s_alloc_mutex);
218	return alloc_count;
219}
220
221static int udf_bitmap_new_block(struct super_block *sb,
222				struct udf_bitmap *bitmap, uint16_t partition,
223				uint32_t goal, int *err)
224{
225	struct udf_sb_info *sbi = UDF_SB(sb);
226	int newbit, bit = 0, block, block_group, group_start;
 
 
227	int end_goal, nr_groups, bitmap_nr, i;
228	struct buffer_head *bh = NULL;
229	char *ptr;
230	int newblock = 0;
231
232	*err = -ENOSPC;
233	mutex_lock(&sbi->s_alloc_mutex);
234
235repeat:
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
316search_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
324got_block:
325	newblock = bit + (block_group << (sb->s_blocksize_bits + 3)) -
326		(sizeof(struct spaceBitmapDesc) << 3);
327
 
 
 
 
 
 
 
 
 
 
 
328	if (!udf_clear_bit(bit, bh->b_data)) {
329		udf_debug("bit already cleared for block %d\n", bit);
330		goto repeat;
331	}
332
333	mark_buffer_dirty(bh);
334
335	udf_add_free_space(sb, partition, -1);
336	mutex_unlock(&sbi->s_alloc_mutex);
337	*err = 0;
338	return newblock;
339
340error_return:
341	*err = -EIO;
342	mutex_unlock(&sbi->s_alloc_mutex);
343	return 0;
344}
345
346static void udf_table_free_blocks(struct super_block *sb,
347				  struct inode *table,
348				  struct kernel_lb_addr *bloc,
349				  uint32_t offset,
350				  uint32_t count)
351{
352	struct udf_sb_info *sbi = UDF_SB(sb);
353	struct udf_part_map *partmap;
354	uint32_t start, end;
355	uint32_t elen;
356	struct kernel_lb_addr eloc;
357	struct extent_position oepos, epos;
358	int8_t etype;
359	struct udf_inode_info *iinfo;
 
360
361	mutex_lock(&sbi->s_alloc_mutex);
362	partmap = &sbi->s_partmaps[bloc->partitionReferenceNum];
363	if (bloc->logicalBlockNum + count < count ||
364	    (bloc->logicalBlockNum + count) > partmap->s_partition_len) {
365		udf_debug("%d < %d || %d + %d > %d\n",
366			  bloc->logicalBlockNum, 0,
367			  bloc->logicalBlockNum, count,
368			  partmap->s_partition_len);
369		goto error_return;
370	}
371
372	iinfo = UDF_I(table);
373	udf_add_free_space(sb, sbi->s_partition, count);
374
375	start = bloc->logicalBlockNum + offset;
376	end = bloc->logicalBlockNum + offset + count - 1;
377
378	epos.offset = oepos.offset = sizeof(struct unallocSpaceEntry);
379	elen = 0;
380	epos.block = oepos.block = iinfo->i_location;
381	epos.bh = oepos.bh = NULL;
382
383	while (count &&
384	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
 
 
 
 
385		if (((eloc.logicalBlockNum +
386			(elen >> sb->s_blocksize_bits)) == start)) {
387			if ((0x3FFFFFFF - elen) <
388					(count << sb->s_blocksize_bits)) {
389				uint32_t tmp = ((0x3FFFFFFF - elen) >>
390							sb->s_blocksize_bits);
391				count -= tmp;
392				start += tmp;
393				elen = (etype << 30) |
394					(0x40000000 - sb->s_blocksize);
395			} else {
396				elen = (etype << 30) |
397					(elen +
398					(count << sb->s_blocksize_bits));
399				start += count;
400				count = 0;
401			}
402			udf_write_aext(table, &oepos, &eloc, elen, 1);
403		} else if (eloc.logicalBlockNum == (end + 1)) {
404			if ((0x3FFFFFFF - elen) <
405					(count << sb->s_blocksize_bits)) {
406				uint32_t tmp = ((0x3FFFFFFF - elen) >>
407						sb->s_blocksize_bits);
408				count -= tmp;
409				end -= tmp;
410				eloc.logicalBlockNum -= tmp;
411				elen = (etype << 30) |
412					(0x40000000 - sb->s_blocksize);
413			} else {
414				eloc.logicalBlockNum = start;
415				elen = (etype << 30) |
416					(elen +
417					(count << sb->s_blocksize_bits));
418				end -= count;
419				count = 0;
420			}
421			udf_write_aext(table, &oepos, &eloc, elen, 1);
422		}
423
424		if (epos.bh != oepos.bh) {
425			oepos.block = epos.block;
426			brelse(oepos.bh);
427			get_bh(epos.bh);
428			oepos.bh = epos.bh;
429			oepos.offset = 0;
430		} else {
431			oepos.offset = epos.offset;
432		}
433	}
434
435	if (count) {
436		/*
437		 * NOTE: we CANNOT use udf_add_aext here, as it can try to
438		 * allocate a new block, and since we hold the super block
439		 * lock already very bad things would happen :)
440		 *
441		 * We copy the behavior of udf_add_aext, but instead of
442		 * trying to allocate a new block close to the existing one,
443		 * we just steal a block from the extent we are trying to add.
444		 *
445		 * It would be nice if the blocks were close together, but it
446		 * isn't required.
447		 */
448
449		int adsize;
450
451		eloc.logicalBlockNum = start;
452		elen = EXT_RECORDED_ALLOCATED |
453			(count << sb->s_blocksize_bits);
454
455		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
456			adsize = sizeof(struct short_ad);
457		else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
458			adsize = sizeof(struct long_ad);
459		else {
460			brelse(oepos.bh);
461			brelse(epos.bh);
462			goto error_return;
463		}
464
465		if (epos.offset + (2 * adsize) > sb->s_blocksize) {
466			/* Steal a block from the extent being free'd */
467			udf_setup_indirect_aext(table, eloc.logicalBlockNum,
468						&epos);
469
470			eloc.logicalBlockNum++;
471			elen -= sb->s_blocksize;
472		}
473
474		/* It's possible that stealing the block emptied the extent */
475		if (elen)
476			__udf_add_aext(table, &epos, &eloc, elen, 1);
477	}
478
 
479	brelse(epos.bh);
480	brelse(oepos.bh);
481
482error_return:
483	mutex_unlock(&sbi->s_alloc_mutex);
484	return;
485}
486
487static int udf_table_prealloc_blocks(struct super_block *sb,
488				     struct inode *table, uint16_t partition,
489				     uint32_t first_block, uint32_t block_count)
490{
491	struct udf_sb_info *sbi = UDF_SB(sb);
492	int alloc_count = 0;
493	uint32_t elen, adsize;
494	struct kernel_lb_addr eloc;
495	struct extent_position epos;
496	int8_t etype = -1;
497	struct udf_inode_info *iinfo;
 
498
499	if (first_block >= sbi->s_partmaps[partition].s_partition_len)
500		return 0;
501
502	iinfo = UDF_I(table);
503	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
504		adsize = sizeof(struct short_ad);
505	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
506		adsize = sizeof(struct long_ad);
507	else
508		return 0;
509
510	mutex_lock(&sbi->s_alloc_mutex);
511	epos.offset = sizeof(struct unallocSpaceEntry);
512	epos.block = iinfo->i_location;
513	epos.bh = NULL;
514	eloc.logicalBlockNum = 0xFFFFFFFF;
515
516	while (first_block != eloc.logicalBlockNum &&
517	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
518		udf_debug("eloc=%d, elen=%d, first_block=%d\n",
 
 
 
 
519			  eloc.logicalBlockNum, elen, first_block);
520		; /* empty loop body */
521	}
522
523	if (first_block == eloc.logicalBlockNum) {
524		epos.offset -= adsize;
525
526		alloc_count = (elen >> sb->s_blocksize_bits);
527		if (alloc_count > block_count) {
528			alloc_count = block_count;
529			eloc.logicalBlockNum += alloc_count;
530			elen -= (alloc_count << sb->s_blocksize_bits);
531			udf_write_aext(table, &epos, &eloc,
532					(etype << 30) | elen, 1);
533		} else
534			udf_delete_aext(table, epos, eloc,
535					(etype << 30) | elen);
536	} else {
537		alloc_count = 0;
538	}
539
 
540	brelse(epos.bh);
541
542	if (alloc_count)
543		udf_add_free_space(sb, partition, -alloc_count);
544	mutex_unlock(&sbi->s_alloc_mutex);
545	return alloc_count;
546}
547
548static int udf_table_new_block(struct super_block *sb,
549			       struct inode *table, uint16_t partition,
550			       uint32_t goal, int *err)
551{
552	struct udf_sb_info *sbi = UDF_SB(sb);
553	uint32_t spread = 0xFFFFFFFF, nspread = 0xFFFFFFFF;
554	uint32_t newblock = 0, adsize;
 
555	uint32_t elen, goal_elen = 0;
556	struct kernel_lb_addr eloc, uninitialized_var(goal_eloc);
557	struct extent_position epos, goal_epos;
558	int8_t etype;
559	struct udf_inode_info *iinfo = UDF_I(table);
 
560
561	*err = -ENOSPC;
562
563	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
564		adsize = sizeof(struct short_ad);
565	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
566		adsize = sizeof(struct long_ad);
567	else
568		return newblock;
569
570	mutex_lock(&sbi->s_alloc_mutex);
571	if (goal >= sbi->s_partmaps[partition].s_partition_len)
572		goal = 0;
573
574	/* We search for the closest matching block to goal. If we find
575	   a exact hit, we stop. Otherwise we keep going till we run out
576	   of extents. We store the buffer_head, bloc, and extoffset
577	   of the current closest match and use that when we are done.
578	 */
579	epos.offset = sizeof(struct unallocSpaceEntry);
580	epos.block = iinfo->i_location;
581	epos.bh = goal_epos.bh = NULL;
582
583	while (spread &&
584	       (etype = udf_next_aext(table, &epos, &eloc, &elen, 1)) != -1) {
 
 
585		if (goal >= eloc.logicalBlockNum) {
586			if (goal < eloc.logicalBlockNum +
587					(elen >> sb->s_blocksize_bits))
588				nspread = 0;
589			else
590				nspread = goal - eloc.logicalBlockNum -
591					(elen >> sb->s_blocksize_bits);
592		} else {
593			nspread = eloc.logicalBlockNum - goal;
594		}
595
596		if (nspread < spread) {
597			spread = nspread;
598			if (goal_epos.bh != epos.bh) {
599				brelse(goal_epos.bh);
600				goal_epos.bh = epos.bh;
601				get_bh(goal_epos.bh);
602			}
603			goal_epos.block = epos.block;
604			goal_epos.offset = epos.offset - adsize;
605			goal_eloc = eloc;
606			goal_elen = (etype << 30) | elen;
607		}
608	}
609
610	brelse(epos.bh);
611
612	if (spread == 0xFFFFFFFF) {
613		brelse(goal_epos.bh);
614		mutex_unlock(&sbi->s_alloc_mutex);
 
 
615		return 0;
616	}
617
618	/* Only allocate blocks from the beginning of the extent.
619	   That way, we only delete (empty) extents, never have to insert an
620	   extent because of splitting */
621	/* This works, but very poorly.... */
622
623	newblock = goal_eloc.logicalBlockNum;
624	goal_eloc.logicalBlockNum++;
625	goal_elen -= sb->s_blocksize;
626
627	if (goal_elen)
628		udf_write_aext(table, &goal_epos, &goal_eloc, goal_elen, 1);
629	else
630		udf_delete_aext(table, goal_epos, goal_eloc, goal_elen);
631	brelse(goal_epos.bh);
632
633	udf_add_free_space(sb, partition, -1);
634
635	mutex_unlock(&sbi->s_alloc_mutex);
636	*err = 0;
637	return newblock;
638}
639
640void udf_free_blocks(struct super_block *sb, struct inode *inode,
641		     struct kernel_lb_addr *bloc, uint32_t offset,
642		     uint32_t count)
643{
644	uint16_t partition = bloc->partitionReferenceNum;
645	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
 
 
 
 
 
 
 
 
 
 
 
646
647	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP) {
648		udf_bitmap_free_blocks(sb, map->s_uspace.s_bitmap,
649				       bloc, offset, count);
650	} else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE) {
651		udf_table_free_blocks(sb, map->s_uspace.s_table,
652				      bloc, offset, count);
653	} else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP) {
654		udf_bitmap_free_blocks(sb, map->s_fspace.s_bitmap,
655				       bloc, offset, count);
656	} else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE) {
657		udf_table_free_blocks(sb, map->s_fspace.s_table,
658				      bloc, offset, count);
659	}
660
661	if (inode) {
662		inode_sub_bytes(inode,
663				((sector_t)count) << sb->s_blocksize_bits);
664	}
665}
666
667inline int udf_prealloc_blocks(struct super_block *sb,
668			       struct inode *inode,
669			       uint16_t partition, uint32_t first_block,
670			       uint32_t block_count)
671{
672	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
673	int allocated;
674
675	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
676		allocated = udf_bitmap_prealloc_blocks(sb,
677						       map->s_uspace.s_bitmap,
678						       partition, first_block,
679						       block_count);
680	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
681		allocated = udf_table_prealloc_blocks(sb,
682						      map->s_uspace.s_table,
683						      partition, first_block,
684						      block_count);
685	else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
686		allocated = udf_bitmap_prealloc_blocks(sb,
687						       map->s_fspace.s_bitmap,
688						       partition, first_block,
689						       block_count);
690	else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
691		allocated = udf_table_prealloc_blocks(sb,
692						      map->s_fspace.s_table,
693						      partition, first_block,
694						      block_count);
695	else
696		return 0;
697
698	if (inode && allocated > 0)
699		inode_add_bytes(inode, allocated << sb->s_blocksize_bits);
700	return allocated;
701}
702
703inline int udf_new_block(struct super_block *sb,
704			 struct inode *inode,
705			 uint16_t partition, uint32_t goal, int *err)
706{
707	struct udf_part_map *map = &UDF_SB(sb)->s_partmaps[partition];
708	int block;
709
710	if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_BITMAP)
711		block = udf_bitmap_new_block(sb,
712					     map->s_uspace.s_bitmap,
713					     partition, goal, err);
714	else if (map->s_partition_flags & UDF_PART_FLAG_UNALLOC_TABLE)
715		block = udf_table_new_block(sb,
716					    map->s_uspace.s_table,
717					    partition, goal, err);
718	else if (map->s_partition_flags & UDF_PART_FLAG_FREED_BITMAP)
719		block = udf_bitmap_new_block(sb,
720					     map->s_fspace.s_bitmap,
721					     partition, goal, err);
722	else if (map->s_partition_flags & UDF_PART_FLAG_FREED_TABLE)
723		block = udf_table_new_block(sb,
724					    map->s_fspace.s_table,
725					    partition, goal, err);
726	else {
727		*err = -EIO;
728		return 0;
729	}
730	if (inode && block)
731		inode_add_bytes(inode, sb->s_blocksize);
732	return block;
733}