xref: /linux/fs/ext2/ialloc.c (revision 0ea5c948cb64bab5bc7a5516774eb8536f05aa0d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext2/ialloc.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  BSD ufs-inspired inode and directory allocation by
11  *  Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
12  *  Big-endian to little-endian byte-swapping/bitmaps by
13  *        David S. Miller (davem@caip.rutgers.edu), 1995
14  */
15 
16 #include <linux/quotaops.h>
17 #include <linux/sched.h>
18 #include <linux/backing-dev.h>
19 #include <linux/buffer_head.h>
20 #include <linux/random.h>
21 #include "ext2.h"
22 #include "xattr.h"
23 #include "acl.h"
24 
25 /*
26  * ialloc.c contains the inodes allocation and deallocation routines
27  */
28 
29 /*
30  * The free inodes are managed by bitmaps.  A file system contains several
31  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
32  * block for inodes, N blocks for the inode table and data blocks.
33  *
34  * The file system contains group descriptors which are located after the
35  * super block.  Each descriptor contains the number of the bitmap block and
36  * the free blocks count in the block.
37  */
38 
39 
40 /*
41  * Read the inode allocation bitmap for a given block_group, reading
42  * into the specified slot in the superblock's bitmap cache.
43  *
44  * Return buffer_head of bitmap on success or NULL.
45  */
46 static struct buffer_head *
read_inode_bitmap(struct super_block * sb,unsigned long block_group)47 read_inode_bitmap(struct super_block * sb, unsigned long block_group)
48 {
49 	struct ext2_group_desc *desc;
50 	struct buffer_head *bh = NULL;
51 
52 	desc = ext2_get_group_desc(sb, block_group, NULL);
53 	if (!desc)
54 		goto error_out;
55 
56 	bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
57 	if (!bh)
58 		ext2_error(sb, "read_inode_bitmap",
59 			    "Cannot read inode bitmap - "
60 			    "block_group = %lu, inode_bitmap = %u",
61 			    block_group, le32_to_cpu(desc->bg_inode_bitmap));
62 error_out:
63 	return bh;
64 }
65 
ext2_release_inode(struct super_block * sb,int group,int dir)66 static void ext2_release_inode(struct super_block *sb, int group, int dir)
67 {
68 	struct ext2_group_desc * desc;
69 	struct buffer_head *bh;
70 
71 	desc = ext2_get_group_desc(sb, group, &bh);
72 	if (!desc) {
73 		ext2_error(sb, "ext2_release_inode",
74 			"can't get descriptor for group %d", group);
75 		return;
76 	}
77 
78 	spin_lock(sb_bgl_lock(EXT2_SB(sb), group));
79 	le16_add_cpu(&desc->bg_free_inodes_count, 1);
80 	if (dir)
81 		le16_add_cpu(&desc->bg_used_dirs_count, -1);
82 	spin_unlock(sb_bgl_lock(EXT2_SB(sb), group));
83 	percpu_counter_inc(&EXT2_SB(sb)->s_freeinodes_counter);
84 	if (dir)
85 		percpu_counter_dec(&EXT2_SB(sb)->s_dirs_counter);
86 	mark_buffer_dirty(bh);
87 }
88 
89 /*
90  * NOTE! When we get the inode, we're the only people
91  * that have access to it, and as such there are no
92  * race conditions we have to worry about. The inode
93  * is not on the hash-lists, and it cannot be reached
94  * through the filesystem because the directory entry
95  * has been deleted earlier.
96  *
97  * HOWEVER: we must make sure that we get no aliases,
98  * which means that we have to call "clear_inode()"
99  * _before_ we mark the inode not in use in the inode
100  * bitmaps. Otherwise a newly created file might use
101  * the same inode number (not actually the same pointer
102  * though), and then we'd have two inodes sharing the
103  * same inode number and space on the harddisk.
104  */
ext2_free_inode(struct inode * inode)105 void ext2_free_inode (struct inode * inode)
106 {
107 	struct super_block * sb = inode->i_sb;
108 	int is_directory;
109 	unsigned long ino;
110 	struct buffer_head *bitmap_bh;
111 	unsigned long block_group;
112 	unsigned long bit;
113 	struct ext2_super_block * es;
114 
115 	ino = inode->i_ino;
116 	ext2_debug ("freeing inode %lu\n", ino);
117 
118 	/*
119 	 * Note: we must free any quota before locking the superblock,
120 	 * as writing the quota to disk may need the lock as well.
121 	 */
122 	/* Quota is already initialized in iput() */
123 	dquot_free_inode(inode);
124 	dquot_drop(inode);
125 
126 	es = EXT2_SB(sb)->s_es;
127 	is_directory = S_ISDIR(inode->i_mode);
128 
129 	if (ino < EXT2_FIRST_INO(sb) ||
130 	    ino > le32_to_cpu(es->s_inodes_count)) {
131 		ext2_error (sb, "ext2_free_inode",
132 			    "reserved or nonexistent inode %lu", ino);
133 		return;
134 	}
135 	block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
136 	bit = (ino - 1) % EXT2_INODES_PER_GROUP(sb);
137 	bitmap_bh = read_inode_bitmap(sb, block_group);
138 	if (!bitmap_bh)
139 		return;
140 
141 	/* Ok, now we can actually update the inode bitmaps.. */
142 	if (!ext2_clear_bit_atomic(sb_bgl_lock(EXT2_SB(sb), block_group),
143 				bit, (void *) bitmap_bh->b_data))
144 		ext2_error (sb, "ext2_free_inode",
145 			      "bit already cleared for inode %lu", ino);
146 	else
147 		ext2_release_inode(sb, block_group, is_directory);
148 	mark_buffer_dirty(bitmap_bh);
149 	if (sb->s_flags & SB_SYNCHRONOUS)
150 		sync_dirty_buffer(bitmap_bh);
151 
152 	brelse(bitmap_bh);
153 }
154 
155 /*
156  * We perform asynchronous prereading of the new inode's inode block when
157  * we create the inode, in the expectation that the inode will be written
158  * back soon.  There are two reasons:
159  *
160  * - When creating a large number of files, the async prereads will be
161  *   nicely merged into large reads
162  * - When writing out a large number of inodes, we don't need to keep on
163  *   stalling the writes while we read the inode block.
164  *
165  * FIXME: ext2_get_group_desc() needs to be simplified.
166  */
ext2_preread_inode(struct inode * inode)167 static void ext2_preread_inode(struct inode *inode)
168 {
169 	unsigned long block_group;
170 	unsigned long offset;
171 	unsigned long block;
172 	struct ext2_group_desc * gdp;
173 
174 	block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb);
175 	gdp = ext2_get_group_desc(inode->i_sb, block_group, NULL);
176 	if (gdp == NULL)
177 		return;
178 
179 	/*
180 	 * Figure out the offset within the block group inode table
181 	 */
182 	offset = ((inode->i_ino - 1) % EXT2_INODES_PER_GROUP(inode->i_sb)) *
183 				EXT2_INODE_SIZE(inode->i_sb);
184 	block = le32_to_cpu(gdp->bg_inode_table) +
185 				(offset >> EXT2_BLOCK_SIZE_BITS(inode->i_sb));
186 	sb_breadahead(inode->i_sb, block);
187 }
188 
189 /*
190  * There are two policies for allocating an inode.  If the new inode is
191  * a directory, then a forward search is made for a block group with both
192  * free space and a low directory-to-inode ratio; if that fails, then of
193  * the groups with above-average free space, that group with the fewest
194  * directories already is chosen.
195  *
196  * For other inodes, search forward from the parent directory\'s block
197  * group to find a free inode.
198  */
find_group_dir(struct super_block * sb,struct inode * parent)199 static int find_group_dir(struct super_block *sb, struct inode *parent)
200 {
201 	int ngroups = EXT2_SB(sb)->s_groups_count;
202 	int avefreei = ext2_count_free_inodes(sb) / ngroups;
203 	struct ext2_group_desc *desc, *best_desc = NULL;
204 	int group, best_group = -1;
205 
206 	for (group = 0; group < ngroups; group++) {
207 		desc = ext2_get_group_desc (sb, group, NULL);
208 		if (!desc || !desc->bg_free_inodes_count)
209 			continue;
210 		if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
211 			continue;
212 		if (!best_desc ||
213 		    (le16_to_cpu(desc->bg_free_blocks_count) >
214 		     le16_to_cpu(best_desc->bg_free_blocks_count))) {
215 			best_group = group;
216 			best_desc = desc;
217 		}
218 	}
219 
220 	return best_group;
221 }
222 
223 /*
224  * Orlov's allocator for directories.
225  *
226  * We always try to spread first-level directories.
227  *
228  * If there are blockgroups with both free inodes and free blocks counts
229  * not worse than average we return one with smallest directory count.
230  * Otherwise we simply return a random group.
231  *
232  * For the rest rules look so:
233  *
234  * It's OK to put directory into a group unless
235  * it has too many directories already (max_dirs) or
236  * it has too few free inodes left (min_inodes) or
237  * it has too few free blocks left (min_blocks) or
238  * it's already running too large debt (max_debt).
239  * Parent's group is preferred, if it doesn't satisfy these
240  * conditions we search cyclically through the rest. If none
241  * of the groups look good we just look for a group with more
242  * free inodes than average (starting at parent's group).
243  *
244  * Debt is incremented each time we allocate a directory and decremented
245  * when we allocate an inode, within 0--255.
246  */
247 
248 #define INODE_COST 64
249 #define BLOCK_COST 256
250 
find_group_orlov(struct super_block * sb,struct inode * parent)251 static int find_group_orlov(struct super_block *sb, struct inode *parent)
252 {
253 	int parent_group = EXT2_I(parent)->i_block_group;
254 	struct ext2_sb_info *sbi = EXT2_SB(sb);
255 	struct ext2_super_block *es = sbi->s_es;
256 	int ngroups = sbi->s_groups_count;
257 	int inodes_per_group = EXT2_INODES_PER_GROUP(sb);
258 	int freei;
259 	int avefreei;
260 	int free_blocks;
261 	int avefreeb;
262 	int blocks_per_dir;
263 	int ndirs;
264 	int max_debt, max_dirs, min_blocks, min_inodes;
265 	int group = -1, i;
266 	struct ext2_group_desc *desc;
267 
268 	freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
269 	avefreei = freei / ngroups;
270 	free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
271 	avefreeb = free_blocks / ngroups;
272 	ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
273 
274 	if ((parent == d_inode(sb->s_root)) ||
275 	    (EXT2_I(parent)->i_flags & EXT2_TOPDIR_FL)) {
276 		int best_ndir = inodes_per_group;
277 		int best_group = -1;
278 
279 		parent_group = get_random_u32_below(ngroups);
280 		for (i = 0; i < ngroups; i++) {
281 			group = (parent_group + i) % ngroups;
282 			desc = ext2_get_group_desc (sb, group, NULL);
283 			if (!desc || !desc->bg_free_inodes_count)
284 				continue;
285 			if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir)
286 				continue;
287 			if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
288 				continue;
289 			if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb)
290 				continue;
291 			best_group = group;
292 			best_ndir = le16_to_cpu(desc->bg_used_dirs_count);
293 		}
294 		if (best_group >= 0) {
295 			group = best_group;
296 			goto found;
297 		}
298 		goto fallback;
299 	}
300 
301 	if (ndirs == 0)
302 		ndirs = 1;	/* percpu_counters are approximate... */
303 
304 	blocks_per_dir = (le32_to_cpu(es->s_blocks_count)-free_blocks) / ndirs;
305 
306 	max_dirs = ndirs / ngroups + inodes_per_group / 16;
307 	min_inodes = avefreei - inodes_per_group / 4;
308 	min_blocks = avefreeb - EXT2_BLOCKS_PER_GROUP(sb) / 4;
309 
310 	max_debt = EXT2_BLOCKS_PER_GROUP(sb) / max(blocks_per_dir, BLOCK_COST);
311 	if (max_debt * INODE_COST > inodes_per_group)
312 		max_debt = inodes_per_group / INODE_COST;
313 	if (max_debt > 255)
314 		max_debt = 255;
315 	if (max_debt == 0)
316 		max_debt = 1;
317 
318 	for (i = 0; i < ngroups; i++) {
319 		group = (parent_group + i) % ngroups;
320 		desc = ext2_get_group_desc (sb, group, NULL);
321 		if (!desc || !desc->bg_free_inodes_count)
322 			continue;
323 		if (sbi->s_debts[group] >= max_debt)
324 			continue;
325 		if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs)
326 			continue;
327 		if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes)
328 			continue;
329 		if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks)
330 			continue;
331 		goto found;
332 	}
333 
334 fallback:
335 	for (i = 0; i < ngroups; i++) {
336 		group = (parent_group + i) % ngroups;
337 		desc = ext2_get_group_desc (sb, group, NULL);
338 		if (!desc || !desc->bg_free_inodes_count)
339 			continue;
340 		if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei)
341 			goto found;
342 	}
343 
344 	if (avefreei) {
345 		/*
346 		 * The free-inodes counter is approximate, and for really small
347 		 * filesystems the above test can fail to find any blockgroups
348 		 */
349 		avefreei = 0;
350 		goto fallback;
351 	}
352 
353 	return -1;
354 
355 found:
356 	return group;
357 }
358 
find_group_other(struct super_block * sb,struct inode * parent)359 static int find_group_other(struct super_block *sb, struct inode *parent)
360 {
361 	int parent_group = EXT2_I(parent)->i_block_group;
362 	int ngroups = EXT2_SB(sb)->s_groups_count;
363 	struct ext2_group_desc *desc;
364 	int group, i;
365 
366 	/*
367 	 * Try to place the inode in its parent directory
368 	 */
369 	group = parent_group;
370 	desc = ext2_get_group_desc (sb, group, NULL);
371 	if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
372 			le16_to_cpu(desc->bg_free_blocks_count))
373 		goto found;
374 
375 	/*
376 	 * We're going to place this inode in a different blockgroup from its
377 	 * parent.  We want to cause files in a common directory to all land in
378 	 * the same blockgroup.  But we want files which are in a different
379 	 * directory which shares a blockgroup with our parent to land in a
380 	 * different blockgroup.
381 	 *
382 	 * So add our directory's i_ino into the starting point for the hash.
383 	 */
384 	group = (group + parent->i_ino) % ngroups;
385 
386 	/*
387 	 * Use a quadratic hash to find a group with a free inode and some
388 	 * free blocks.
389 	 */
390 	for (i = 1; i < ngroups; i <<= 1) {
391 		group += i;
392 		if (group >= ngroups)
393 			group -= ngroups;
394 		desc = ext2_get_group_desc (sb, group, NULL);
395 		if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
396 				le16_to_cpu(desc->bg_free_blocks_count))
397 			goto found;
398 	}
399 
400 	/*
401 	 * That failed: try linear search for a free inode, even if that group
402 	 * has no free blocks.
403 	 */
404 	group = parent_group;
405 	for (i = 0; i < ngroups; i++) {
406 		if (++group >= ngroups)
407 			group = 0;
408 		desc = ext2_get_group_desc (sb, group, NULL);
409 		if (desc && le16_to_cpu(desc->bg_free_inodes_count))
410 			goto found;
411 	}
412 
413 	return -1;
414 
415 found:
416 	return group;
417 }
418 
ext2_new_inode(struct inode * dir,umode_t mode,const struct qstr * qstr)419 struct inode *ext2_new_inode(struct inode *dir, umode_t mode,
420 			     const struct qstr *qstr)
421 {
422 	struct super_block *sb;
423 	struct buffer_head *bitmap_bh = NULL;
424 	struct buffer_head *bh2;
425 	int group, i;
426 	ino_t ino = 0;
427 	struct inode * inode;
428 	struct ext2_group_desc *gdp;
429 	struct ext2_super_block *es;
430 	struct ext2_inode_info *ei;
431 	struct ext2_sb_info *sbi;
432 	int err;
433 
434 	sb = dir->i_sb;
435 	inode = new_inode(sb);
436 	if (!inode)
437 		return ERR_PTR(-ENOMEM);
438 
439 	ei = EXT2_I(inode);
440 	sbi = EXT2_SB(sb);
441 	es = sbi->s_es;
442 	if (S_ISDIR(mode)) {
443 		if (test_opt(sb, OLDALLOC))
444 			group = find_group_dir(sb, dir);
445 		else
446 			group = find_group_orlov(sb, dir);
447 	} else
448 		group = find_group_other(sb, dir);
449 
450 	if (group == -1) {
451 		err = -ENOSPC;
452 		goto fail;
453 	}
454 
455 	for (i = 0; i < sbi->s_groups_count; i++) {
456 		gdp = ext2_get_group_desc(sb, group, &bh2);
457 		if (!gdp) {
458 			if (++group == sbi->s_groups_count)
459 				group = 0;
460 			continue;
461 		}
462 		brelse(bitmap_bh);
463 		bitmap_bh = read_inode_bitmap(sb, group);
464 		if (!bitmap_bh) {
465 			err = -EIO;
466 			goto fail;
467 		}
468 		ino = 0;
469 
470 repeat_in_this_group:
471 		ino = ext2_find_next_zero_bit((unsigned long *)bitmap_bh->b_data,
472 					      EXT2_INODES_PER_GROUP(sb), ino);
473 		if (ino >= EXT2_INODES_PER_GROUP(sb)) {
474 			/*
475 			 * Rare race: find_group_xx() decided that there were
476 			 * free inodes in this group, but by the time we tried
477 			 * to allocate one, they're all gone.  This can also
478 			 * occur because the counters which find_group_orlov()
479 			 * uses are approximate.  So just go and search the
480 			 * next block group.
481 			 */
482 			if (++group == sbi->s_groups_count)
483 				group = 0;
484 			continue;
485 		}
486 		if (ext2_set_bit_atomic(sb_bgl_lock(sbi, group),
487 						ino, bitmap_bh->b_data)) {
488 			/* we lost this inode */
489 			if (++ino >= EXT2_INODES_PER_GROUP(sb)) {
490 				/* this group is exhausted, try next group */
491 				if (++group == sbi->s_groups_count)
492 					group = 0;
493 				continue;
494 			}
495 			/* try to find free inode in the same group */
496 			goto repeat_in_this_group;
497 		}
498 		goto got;
499 	}
500 
501 	/*
502 	 * Scanned all blockgroups.
503 	 */
504 	brelse(bitmap_bh);
505 	err = -ENOSPC;
506 	goto fail;
507 got:
508 	mark_buffer_dirty(bitmap_bh);
509 	if (sb->s_flags & SB_SYNCHRONOUS)
510 		sync_dirty_buffer(bitmap_bh);
511 	brelse(bitmap_bh);
512 
513 	ino += group * EXT2_INODES_PER_GROUP(sb) + 1;
514 	if (ino < EXT2_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
515 		ext2_error (sb, "ext2_new_inode",
516 			    "reserved inode or inode > inodes count - "
517 			    "block_group = %d,inode=%lu", group,
518 			    (unsigned long) ino);
519 		err = -EIO;
520 		goto fail;
521 	}
522 
523 	percpu_counter_dec(&sbi->s_freeinodes_counter);
524 	if (S_ISDIR(mode))
525 		percpu_counter_inc(&sbi->s_dirs_counter);
526 
527 	spin_lock(sb_bgl_lock(sbi, group));
528 	le16_add_cpu(&gdp->bg_free_inodes_count, -1);
529 	if (S_ISDIR(mode)) {
530 		if (sbi->s_debts[group] < 255)
531 			sbi->s_debts[group]++;
532 		le16_add_cpu(&gdp->bg_used_dirs_count, 1);
533 	} else {
534 		if (sbi->s_debts[group])
535 			sbi->s_debts[group]--;
536 	}
537 	spin_unlock(sb_bgl_lock(sbi, group));
538 
539 	mark_buffer_dirty(bh2);
540 	if (test_opt(sb, GRPID)) {
541 		inode->i_mode = mode;
542 		inode->i_uid = current_fsuid();
543 		inode->i_gid = dir->i_gid;
544 	} else
545 		inode_init_owner(&nop_mnt_idmap, inode, dir, mode);
546 
547 	inode->i_ino = ino;
548 	inode->i_blocks = 0;
549 	simple_inode_init_ts(inode);
550 	memset(ei->i_data, 0, sizeof(ei->i_data));
551 	ei->i_flags =
552 		ext2_mask_flags(mode, EXT2_I(dir)->i_flags & EXT2_FL_INHERITED);
553 	ei->i_faddr = 0;
554 	ei->i_frag_no = 0;
555 	ei->i_frag_size = 0;
556 	ei->i_file_acl = 0;
557 	ei->i_dir_acl = 0;
558 	ei->i_dtime = 0;
559 	ei->i_block_alloc_info = NULL;
560 	ei->i_block_group = group;
561 	ei->i_dir_start_lookup = 0;
562 	ei->i_state = EXT2_STATE_NEW;
563 	ext2_set_inode_flags(inode);
564 	spin_lock(&sbi->s_next_gen_lock);
565 	inode->i_generation = sbi->s_next_generation++;
566 	spin_unlock(&sbi->s_next_gen_lock);
567 	if (insert_inode_locked(inode) < 0) {
568 		ext2_error(sb, "ext2_new_inode",
569 			   "inode number already in use - inode=%lu",
570 			   (unsigned long) ino);
571 		err = -EIO;
572 		goto fail;
573 	}
574 
575 	err = dquot_initialize(inode);
576 	if (err)
577 		goto fail_drop;
578 
579 	err = dquot_alloc_inode(inode);
580 	if (err)
581 		goto fail_drop;
582 
583 	err = ext2_init_acl(inode, dir);
584 	if (err)
585 		goto fail_free_drop;
586 
587 	err = ext2_init_security(inode, dir, qstr);
588 	if (err)
589 		goto fail_free_drop;
590 
591 	mark_inode_dirty(inode);
592 	ext2_debug("allocating inode %lu\n", inode->i_ino);
593 	ext2_preread_inode(inode);
594 	return inode;
595 
596 fail_free_drop:
597 	dquot_free_inode(inode);
598 
599 fail_drop:
600 	dquot_drop(inode);
601 	inode->i_flags |= S_NOQUOTA;
602 	clear_nlink(inode);
603 	discard_new_inode(inode);
604 	return ERR_PTR(err);
605 
606 fail:
607 	make_bad_inode(inode);
608 	iput(inode);
609 	return ERR_PTR(err);
610 }
611 
ext2_count_free_inodes(struct super_block * sb)612 unsigned long ext2_count_free_inodes (struct super_block * sb)
613 {
614 	struct ext2_group_desc *desc;
615 	unsigned long desc_count = 0;
616 	int i;
617 
618 #ifdef EXT2FS_DEBUG
619 	struct ext2_super_block *es;
620 	unsigned long bitmap_count = 0;
621 	struct buffer_head *bitmap_bh = NULL;
622 
623 	es = EXT2_SB(sb)->s_es;
624 	for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
625 		unsigned x;
626 
627 		desc = ext2_get_group_desc (sb, i, NULL);
628 		if (!desc)
629 			continue;
630 		desc_count += le16_to_cpu(desc->bg_free_inodes_count);
631 		brelse(bitmap_bh);
632 		bitmap_bh = read_inode_bitmap(sb, i);
633 		if (!bitmap_bh)
634 			continue;
635 
636 		x = ext2_count_free(bitmap_bh, EXT2_INODES_PER_GROUP(sb) / 8);
637 		printk("group %d: stored = %d, counted = %u\n",
638 			i, le16_to_cpu(desc->bg_free_inodes_count), x);
639 		bitmap_count += x;
640 	}
641 	brelse(bitmap_bh);
642 	printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
643 		(unsigned long)
644 		percpu_counter_read(&EXT2_SB(sb)->s_freeinodes_counter),
645 		desc_count, bitmap_count);
646 	return desc_count;
647 #else
648 	for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
649 		desc = ext2_get_group_desc (sb, i, NULL);
650 		if (!desc)
651 			continue;
652 		desc_count += le16_to_cpu(desc->bg_free_inodes_count);
653 	}
654 	return desc_count;
655 #endif
656 }
657 
658 /* Called at mount-time, super-block is locked */
ext2_count_dirs(struct super_block * sb)659 unsigned long ext2_count_dirs (struct super_block * sb)
660 {
661 	unsigned long count = 0;
662 	int i;
663 
664 	for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
665 		struct ext2_group_desc *gdp = ext2_get_group_desc (sb, i, NULL);
666 		if (!gdp)
667 			continue;
668 		count += le16_to_cpu(gdp->bg_used_dirs_count);
669 	}
670 	return count;
671 }
672 
673