~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/ext2/ialloc.c

Version: ~ [ linux-5.8-rc4 ] ~ [ linux-5.7.7 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.50 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.131 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.187 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.229 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.229 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.85 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  *  linux/fs/ext2/ialloc.c
  3  *
  4  * Copyright (C) 1992, 1993, 1994, 1995
  5  * Remy Card (card@masi.ibp.fr)
  6  * Laboratoire MASI - Institut Blaise Pascal
  7  * Universite Pierre et Marie Curie (Paris VI)
  8  *
  9  *  BSD ufs-inspired inode and directory allocation by 
 10  *  Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
 11  *  Big-endian to little-endian byte-swapping/bitmaps by
 12  *        David S. Miller (davem@caip.rutgers.edu), 1995
 13  */
 14 
 15 #include <linux/quotaops.h>
 16 #include <linux/sched.h>
 17 #include <linux/backing-dev.h>
 18 #include <linux/buffer_head.h>
 19 #include <linux/random.h>
 20 #include "ext2.h"
 21 #include "xattr.h"
 22 #include "acl.h"
 23 
 24 /*
 25  * ialloc.c contains the inodes allocation and deallocation routines
 26  */
 27 
 28 /*
 29  * The free inodes are managed by bitmaps.  A file system contains several
 30  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
 31  * block for inodes, N blocks for the inode table and data blocks.
 32  *
 33  * The file system contains group descriptors which are located after the
 34  * super block.  Each descriptor contains the number of the bitmap block and
 35  * the free blocks count in the block.
 36  */
 37 
 38 
 39 /*
 40  * Read the inode allocation bitmap for a given block_group, reading
 41  * into the specified slot in the superblock's bitmap cache.
 42  *
 43  * Return buffer_head of bitmap on success or NULL.
 44  */
 45 static struct buffer_head *
 46 read_inode_bitmap(struct super_block * sb, unsigned long block_group)
 47 {
 48         struct ext2_group_desc *desc;
 49         struct buffer_head *bh = NULL;
 50 
 51         desc = ext2_get_group_desc(sb, block_group, NULL);
 52         if (!desc)
 53                 goto error_out;
 54 
 55         bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
 56         if (!bh)
 57                 ext2_error(sb, "read_inode_bitmap",
 58                             "Cannot read inode bitmap - "
 59                             "block_group = %lu, inode_bitmap = %u",
 60                             block_group, le32_to_cpu(desc->bg_inode_bitmap));
 61 error_out:
 62         return bh;
 63 }
 64 
 65 static void ext2_release_inode(struct super_block *sb, int group, int dir)
 66 {
 67         struct ext2_group_desc * desc;
 68         struct buffer_head *bh;
 69 
 70         desc = ext2_get_group_desc(sb, group, &bh);
 71         if (!desc) {
 72                 ext2_error(sb, "ext2_release_inode",
 73                         "can't get descriptor for group %d", group);
 74                 return;
 75         }
 76 
 77         spin_lock(sb_bgl_lock(EXT2_SB(sb), group));
 78         le16_add_cpu(&desc->bg_free_inodes_count, 1);
 79         if (dir)
 80                 le16_add_cpu(&desc->bg_used_dirs_count, -1);
 81         spin_unlock(sb_bgl_lock(EXT2_SB(sb), group));
 82         if (dir)
 83                 percpu_counter_dec(&EXT2_SB(sb)->s_dirs_counter);
 84         mark_buffer_dirty(bh);
 85 }
 86 
 87 /*
 88  * NOTE! When we get the inode, we're the only people
 89  * that have access to it, and as such there are no
 90  * race conditions we have to worry about. The inode
 91  * is not on the hash-lists, and it cannot be reached
 92  * through the filesystem because the directory entry
 93  * has been deleted earlier.
 94  *
 95  * HOWEVER: we must make sure that we get no aliases,
 96  * which means that we have to call "clear_inode()"
 97  * _before_ we mark the inode not in use in the inode
 98  * bitmaps. Otherwise a newly created file might use
 99  * the same inode number (not actually the same pointer
100  * though), and then we'd have two inodes sharing the
101  * same inode number and space on the harddisk.
102  */
103 void ext2_free_inode (struct inode * inode)
104 {
105         struct super_block * sb = inode->i_sb;
106         int is_directory;
107         unsigned long ino;
108         struct buffer_head *bitmap_bh;
109         unsigned long block_group;
110         unsigned long bit;
111         struct ext2_super_block * es;
112 
113         ino = inode->i_ino;
114         ext2_debug ("freeing inode %lu\n", ino);
115 
116         /*
117          * Note: we must free any quota before locking the superblock,
118          * as writing the quota to disk may need the lock as well.
119          */
120         /* Quota is already initialized in iput() */
121         dquot_free_inode(inode);
122         dquot_drop(inode);
123 
124         es = EXT2_SB(sb)->s_es;
125         is_directory = S_ISDIR(inode->i_mode);
126 
127         if (ino < EXT2_FIRST_INO(sb) ||
128             ino > le32_to_cpu(es->s_inodes_count)) {
129                 ext2_error (sb, "ext2_free_inode",
130                             "reserved or nonexistent inode %lu", ino);
131                 return;
132         }
133         block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
134         bit = (ino - 1) % EXT2_INODES_PER_GROUP(sb);
135         bitmap_bh = read_inode_bitmap(sb, block_group);
136         if (!bitmap_bh)
137                 return;
138 
139         /* Ok, now we can actually update the inode bitmaps.. */
140         if (!ext2_clear_bit_atomic(sb_bgl_lock(EXT2_SB(sb), block_group),
141                                 bit, (void *) bitmap_bh->b_data))
142                 ext2_error (sb, "ext2_free_inode",
143                               "bit already cleared for inode %lu", ino);
144         else
145                 ext2_release_inode(sb, block_group, is_directory);
146         mark_buffer_dirty(bitmap_bh);
147         if (sb->s_flags & MS_SYNCHRONOUS)
148                 sync_dirty_buffer(bitmap_bh);
149 
150         brelse(bitmap_bh);
151 }
152 
153 /*
154  * We perform asynchronous prereading of the new inode's inode block when
155  * we create the inode, in the expectation that the inode will be written
156  * back soon.  There are two reasons:
157  *
158  * - When creating a large number of files, the async prereads will be
159  *   nicely merged into large reads
160  * - When writing out a large number of inodes, we don't need to keep on
161  *   stalling the writes while we read the inode block.
162  *
163  * FIXME: ext2_get_group_desc() needs to be simplified.
164  */
165 static void ext2_preread_inode(struct inode *inode)
166 {
167         unsigned long block_group;
168         unsigned long offset;
169         unsigned long block;
170         struct ext2_group_desc * gdp;
171         struct backing_dev_info *bdi;
172 
173         bdi = inode_to_bdi(inode);
174         if (bdi_read_congested(bdi))
175                 return;
176         if (bdi_write_congested(bdi))
177                 return;
178 
179         block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb);
180         gdp = ext2_get_group_desc(inode->i_sb, block_group, NULL);
181         if (gdp == NULL)
182                 return;
183 
184         /*
185          * Figure out the offset within the block group inode table
186          */
187         offset = ((inode->i_ino - 1) % EXT2_INODES_PER_GROUP(inode->i_sb)) *
188                                 EXT2_INODE_SIZE(inode->i_sb);
189         block = le32_to_cpu(gdp->bg_inode_table) +
190                                 (offset >> EXT2_BLOCK_SIZE_BITS(inode->i_sb));
191         sb_breadahead(inode->i_sb, block);
192 }
193 
194 /*
195  * There are two policies for allocating an inode.  If the new inode is
196  * a directory, then a forward search is made for a block group with both
197  * free space and a low directory-to-inode ratio; if that fails, then of
198  * the groups with above-average free space, that group with the fewest
199  * directories already is chosen.
200  *
201  * For other inodes, search forward from the parent directory\'s block
202  * group to find a free inode.
203  */
204 static int find_group_dir(struct super_block *sb, struct inode *parent)
205 {
206         int ngroups = EXT2_SB(sb)->s_groups_count;
207         int avefreei = ext2_count_free_inodes(sb) / ngroups;
208         struct ext2_group_desc *desc, *best_desc = NULL;
209         int group, best_group = -1;
210 
211         for (group = 0; group < ngroups; group++) {
212                 desc = ext2_get_group_desc (sb, group, NULL);
213                 if (!desc || !desc->bg_free_inodes_count)
214                         continue;
215                 if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
216                         continue;
217                 if (!best_desc || 
218                     (le16_to_cpu(desc->bg_free_blocks_count) >
219                      le16_to_cpu(best_desc->bg_free_blocks_count))) {
220                         best_group = group;
221                         best_desc = desc;
222                 }
223         }
224         if (!best_desc)
225                 return -1;
226 
227         return best_group;
228 }
229 
230 /* 
231  * Orlov's allocator for directories. 
232  * 
233  * We always try to spread first-level directories.
234  *
235  * If there are blockgroups with both free inodes and free blocks counts 
236  * not worse than average we return one with smallest directory count. 
237  * Otherwise we simply return a random group. 
238  * 
239  * For the rest rules look so: 
240  * 
241  * It's OK to put directory into a group unless 
242  * it has too many directories already (max_dirs) or 
243  * it has too few free inodes left (min_inodes) or 
244  * it has too few free blocks left (min_blocks) or 
245  * it's already running too large debt (max_debt). 
246  * Parent's group is preferred, if it doesn't satisfy these 
247  * conditions we search cyclically through the rest. If none 
248  * of the groups look good we just look for a group with more 
249  * free inodes than average (starting at parent's group). 
250  * 
251  * Debt is incremented each time we allocate a directory and decremented 
252  * when we allocate an inode, within 0--255. 
253  */ 
254 
255 #define INODE_COST 64
256 #define BLOCK_COST 256
257 
258 static int find_group_orlov(struct super_block *sb, struct inode *parent)
259 {
260         int parent_group = EXT2_I(parent)->i_block_group;
261         struct ext2_sb_info *sbi = EXT2_SB(sb);
262         struct ext2_super_block *es = sbi->s_es;
263         int ngroups = sbi->s_groups_count;
264         int inodes_per_group = EXT2_INODES_PER_GROUP(sb);
265         int freei;
266         int avefreei;
267         int free_blocks;
268         int avefreeb;
269         int blocks_per_dir;
270         int ndirs;
271         int max_debt, max_dirs, min_blocks, min_inodes;
272         int group = -1, i;
273         struct ext2_group_desc *desc;
274 
275         freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
276         avefreei = freei / ngroups;
277         free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
278         avefreeb = free_blocks / ngroups;
279         ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
280 
281         if ((parent == d_inode(sb->s_root)) ||
282             (EXT2_I(parent)->i_flags & EXT2_TOPDIR_FL)) {
283                 struct ext2_group_desc *best_desc = NULL;
284                 int best_ndir = inodes_per_group;
285                 int best_group = -1;
286 
287                 group = prandom_u32();
288                 parent_group = (unsigned)group % ngroups;
289                 for (i = 0; i < ngroups; i++) {
290                         group = (parent_group + i) % ngroups;
291                         desc = ext2_get_group_desc (sb, group, NULL);
292                         if (!desc || !desc->bg_free_inodes_count)
293                                 continue;
294                         if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir)
295                                 continue;
296                         if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
297                                 continue;
298                         if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb)
299                                 continue;
300                         best_group = group;
301                         best_ndir = le16_to_cpu(desc->bg_used_dirs_count);
302                         best_desc = desc;
303                 }
304                 if (best_group >= 0) {
305                         desc = best_desc;
306                         group = best_group;
307                         goto found;
308                 }
309                 goto fallback;
310         }
311 
312         if (ndirs == 0)
313                 ndirs = 1;      /* percpu_counters are approximate... */
314 
315         blocks_per_dir = (le32_to_cpu(es->s_blocks_count)-free_blocks) / ndirs;
316 
317         max_dirs = ndirs / ngroups + inodes_per_group / 16;
318         min_inodes = avefreei - inodes_per_group / 4;
319         min_blocks = avefreeb - EXT2_BLOCKS_PER_GROUP(sb) / 4;
320 
321         max_debt = EXT2_BLOCKS_PER_GROUP(sb) / max(blocks_per_dir, BLOCK_COST);
322         if (max_debt * INODE_COST > inodes_per_group)
323                 max_debt = inodes_per_group / INODE_COST;
324         if (max_debt > 255)
325                 max_debt = 255;
326         if (max_debt == 0)
327                 max_debt = 1;
328 
329         for (i = 0; i < ngroups; i++) {
330                 group = (parent_group + i) % ngroups;
331                 desc = ext2_get_group_desc (sb, group, NULL);
332                 if (!desc || !desc->bg_free_inodes_count)
333                         continue;
334                 if (sbi->s_debts[group] >= max_debt)
335                         continue;
336                 if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs)
337                         continue;
338                 if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes)
339                         continue;
340                 if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks)
341                         continue;
342                 goto found;
343         }
344 
345 fallback:
346         for (i = 0; i < ngroups; i++) {
347                 group = (parent_group + i) % ngroups;
348                 desc = ext2_get_group_desc (sb, group, NULL);
349                 if (!desc || !desc->bg_free_inodes_count)
350                         continue;
351                 if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei)
352                         goto found;
353         }
354 
355         if (avefreei) {
356                 /*
357                  * The free-inodes counter is approximate, and for really small
358                  * filesystems the above test can fail to find any blockgroups
359                  */
360                 avefreei = 0;
361                 goto fallback;
362         }
363 
364         return -1;
365 
366 found:
367         return group;
368 }
369 
370 static int find_group_other(struct super_block *sb, struct inode *parent)
371 {
372         int parent_group = EXT2_I(parent)->i_block_group;
373         int ngroups = EXT2_SB(sb)->s_groups_count;
374         struct ext2_group_desc *desc;
375         int group, i;
376 
377         /*
378          * Try to place the inode in its parent directory
379          */
380         group = parent_group;
381         desc = ext2_get_group_desc (sb, group, NULL);
382         if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
383                         le16_to_cpu(desc->bg_free_blocks_count))
384                 goto found;
385 
386         /*
387          * We're going to place this inode in a different blockgroup from its
388          * parent.  We want to cause files in a common directory to all land in
389          * the same blockgroup.  But we want files which are in a different
390          * directory which shares a blockgroup with our parent to land in a
391          * different blockgroup.
392          *
393          * So add our directory's i_ino into the starting point for the hash.
394          */
395         group = (group + parent->i_ino) % ngroups;
396 
397         /*
398          * Use a quadratic hash to find a group with a free inode and some
399          * free blocks.
400          */
401         for (i = 1; i < ngroups; i <<= 1) {
402                 group += i;
403                 if (group >= ngroups)
404                         group -= ngroups;
405                 desc = ext2_get_group_desc (sb, group, NULL);
406                 if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
407                                 le16_to_cpu(desc->bg_free_blocks_count))
408                         goto found;
409         }
410 
411         /*
412          * That failed: try linear search for a free inode, even if that group
413          * has no free blocks.
414          */
415         group = parent_group;
416         for (i = 0; i < ngroups; i++) {
417                 if (++group >= ngroups)
418                         group = 0;
419                 desc = ext2_get_group_desc (sb, group, NULL);
420                 if (desc && le16_to_cpu(desc->bg_free_inodes_count))
421                         goto found;
422         }
423 
424         return -1;
425 
426 found:
427         return group;
428 }
429 
430 struct inode *ext2_new_inode(struct inode *dir, umode_t mode,
431                              const struct qstr *qstr)
432 {
433         struct super_block *sb;
434         struct buffer_head *bitmap_bh = NULL;
435         struct buffer_head *bh2;
436         int group, i;
437         ino_t ino = 0;
438         struct inode * inode;
439         struct ext2_group_desc *gdp;
440         struct ext2_super_block *es;
441         struct ext2_inode_info *ei;
442         struct ext2_sb_info *sbi;
443         int err;
444 
445         sb = dir->i_sb;
446         inode = new_inode(sb);
447         if (!inode)
448                 return ERR_PTR(-ENOMEM);
449 
450         ei = EXT2_I(inode);
451         sbi = EXT2_SB(sb);
452         es = sbi->s_es;
453         if (S_ISDIR(mode)) {
454                 if (test_opt(sb, OLDALLOC))
455                         group = find_group_dir(sb, dir);
456                 else
457                         group = find_group_orlov(sb, dir);
458         } else 
459                 group = find_group_other(sb, dir);
460 
461         if (group == -1) {
462                 err = -ENOSPC;
463                 goto fail;
464         }
465 
466         for (i = 0; i < sbi->s_groups_count; i++) {
467                 gdp = ext2_get_group_desc(sb, group, &bh2);
468                 brelse(bitmap_bh);
469                 bitmap_bh = read_inode_bitmap(sb, group);
470                 if (!bitmap_bh) {
471                         err = -EIO;
472                         goto fail;
473                 }
474                 ino = 0;
475 
476 repeat_in_this_group:
477                 ino = ext2_find_next_zero_bit((unsigned long *)bitmap_bh->b_data,
478                                               EXT2_INODES_PER_GROUP(sb), ino);
479                 if (ino >= EXT2_INODES_PER_GROUP(sb)) {
480                         /*
481                          * Rare race: find_group_xx() decided that there were
482                          * free inodes in this group, but by the time we tried
483                          * to allocate one, they're all gone.  This can also
484                          * occur because the counters which find_group_orlov()
485                          * uses are approximate.  So just go and search the
486                          * next block group.
487                          */
488                         if (++group == sbi->s_groups_count)
489                                 group = 0;
490                         continue;
491                 }
492                 if (ext2_set_bit_atomic(sb_bgl_lock(sbi, group),
493                                                 ino, bitmap_bh->b_data)) {
494                         /* we lost this inode */
495                         if (++ino >= EXT2_INODES_PER_GROUP(sb)) {
496                                 /* this group is exhausted, try next group */
497                                 if (++group == sbi->s_groups_count)
498                                         group = 0;
499                                 continue;
500                         }
501                         /* try to find free inode in the same group */
502                         goto repeat_in_this_group;
503                 }
504                 goto got;
505         }
506 
507         /*
508          * Scanned all blockgroups.
509          */
510         err = -ENOSPC;
511         goto fail;
512 got:
513         mark_buffer_dirty(bitmap_bh);
514         if (sb->s_flags & MS_SYNCHRONOUS)
515                 sync_dirty_buffer(bitmap_bh);
516         brelse(bitmap_bh);
517 
518         ino += group * EXT2_INODES_PER_GROUP(sb) + 1;
519         if (ino < EXT2_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
520                 ext2_error (sb, "ext2_new_inode",
521                             "reserved inode or inode > inodes count - "
522                             "block_group = %d,inode=%lu", group,
523                             (unsigned long) ino);
524                 err = -EIO;
525                 goto fail;
526         }
527 
528         percpu_counter_add(&sbi->s_freeinodes_counter, -1);
529         if (S_ISDIR(mode))
530                 percpu_counter_inc(&sbi->s_dirs_counter);
531 
532         spin_lock(sb_bgl_lock(sbi, group));
533         le16_add_cpu(&gdp->bg_free_inodes_count, -1);
534         if (S_ISDIR(mode)) {
535                 if (sbi->s_debts[group] < 255)
536                         sbi->s_debts[group]++;
537                 le16_add_cpu(&gdp->bg_used_dirs_count, 1);
538         } else {
539                 if (sbi->s_debts[group])
540                         sbi->s_debts[group]--;
541         }
542         spin_unlock(sb_bgl_lock(sbi, group));
543 
544         mark_buffer_dirty(bh2);
545         if (test_opt(sb, GRPID)) {
546                 inode->i_mode = mode;
547                 inode->i_uid = current_fsuid();
548                 inode->i_gid = dir->i_gid;
549         } else
550                 inode_init_owner(inode, dir, mode);
551 
552         inode->i_ino = ino;
553         inode->i_blocks = 0;
554         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
555         memset(ei->i_data, 0, sizeof(ei->i_data));
556         ei->i_flags =
557                 ext2_mask_flags(mode, EXT2_I(dir)->i_flags & EXT2_FL_INHERITED);
558         ei->i_faddr = 0;
559         ei->i_frag_no = 0;
560         ei->i_frag_size = 0;
561         ei->i_file_acl = 0;
562         ei->i_dir_acl = 0;
563         ei->i_dtime = 0;
564         ei->i_block_alloc_info = NULL;
565         ei->i_block_group = group;
566         ei->i_dir_start_lookup = 0;
567         ei->i_state = EXT2_STATE_NEW;
568         ext2_set_inode_flags(inode);
569         spin_lock(&sbi->s_next_gen_lock);
570         inode->i_generation = sbi->s_next_generation++;
571         spin_unlock(&sbi->s_next_gen_lock);
572         if (insert_inode_locked(inode) < 0) {
573                 ext2_error(sb, "ext2_new_inode",
574                            "inode number already in use - inode=%lu",
575                            (unsigned long) ino);
576                 err = -EIO;
577                 goto fail;
578         }
579 
580         err = dquot_initialize(inode);
581         if (err)
582                 goto fail_drop;
583 
584         err = dquot_alloc_inode(inode);
585         if (err)
586                 goto fail_drop;
587 
588         err = ext2_init_acl(inode, dir);
589         if (err)
590                 goto fail_free_drop;
591 
592         err = ext2_init_security(inode, dir, qstr);
593         if (err)
594                 goto fail_free_drop;
595 
596         mark_inode_dirty(inode);
597         ext2_debug("allocating inode %lu\n", inode->i_ino);
598         ext2_preread_inode(inode);
599         return inode;
600 
601 fail_free_drop:
602         dquot_free_inode(inode);
603 
604 fail_drop:
605         dquot_drop(inode);
606         inode->i_flags |= S_NOQUOTA;
607         clear_nlink(inode);
608         unlock_new_inode(inode);
609         iput(inode);
610         return ERR_PTR(err);
611 
612 fail:
613         make_bad_inode(inode);
614         iput(inode);
615         return ERR_PTR(err);
616 }
617 
618 unsigned long ext2_count_free_inodes (struct super_block * sb)
619 {
620         struct ext2_group_desc *desc;
621         unsigned long desc_count = 0;
622         int i;  
623 
624 #ifdef EXT2FS_DEBUG
625         struct ext2_super_block *es;
626         unsigned long bitmap_count = 0;
627         struct buffer_head *bitmap_bh = NULL;
628 
629         es = EXT2_SB(sb)->s_es;
630         for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
631                 unsigned x;
632 
633                 desc = ext2_get_group_desc (sb, i, NULL);
634                 if (!desc)
635                         continue;
636                 desc_count += le16_to_cpu(desc->bg_free_inodes_count);
637                 brelse(bitmap_bh);
638                 bitmap_bh = read_inode_bitmap(sb, i);
639                 if (!bitmap_bh)
640                         continue;
641 
642                 x = ext2_count_free(bitmap_bh, EXT2_INODES_PER_GROUP(sb) / 8);
643                 printk("group %d: stored = %d, counted = %u\n",
644                         i, le16_to_cpu(desc->bg_free_inodes_count), x);
645                 bitmap_count += x;
646         }
647         brelse(bitmap_bh);
648         printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
649                 (unsigned long)
650                 percpu_counter_read(&EXT2_SB(sb)->s_freeinodes_counter),
651                 desc_count, bitmap_count);
652         return desc_count;
653 #else
654         for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
655                 desc = ext2_get_group_desc (sb, i, NULL);
656                 if (!desc)
657                         continue;
658                 desc_count += le16_to_cpu(desc->bg_free_inodes_count);
659         }
660         return desc_count;
661 #endif
662 }
663 
664 /* Called at mount-time, super-block is locked */
665 unsigned long ext2_count_dirs (struct super_block * sb)
666 {
667         unsigned long count = 0;
668         int i;
669 
670         for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
671                 struct ext2_group_desc *gdp = ext2_get_group_desc (sb, i, NULL);
672                 if (!gdp)
673                         continue;
674                 count += le16_to_cpu(gdp->bg_used_dirs_count);
675         }
676         return count;
677 }
678 
679 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp