ialloc.c

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			for (j = 0; j < sb->u.ext3_sb.s_groups_count; j++) {
				struct buffer_head *temp_buffer;
				tmp = ext3_get_group_desc (sb, j, &temp_buffer);
				if (tmp &&
				    le16_to_cpu(tmp->bg_free_inodes_count) &&
				    le16_to_cpu(tmp->bg_free_inodes_count) >=
							avefreei) {
					if (!gdp || (le16_to_cpu(tmp->bg_free_blocks_count) >
						le16_to_cpu(gdp->bg_free_blocks_count))) {
						i = j;
						gdp = tmp;
						bh2 = temp_buffer;
					}
				}
			}
		}
	} else {
		/*
		 * Try to place the inode in its parent directory
		 */
		i = dir->u.ext3_i.i_block_group;
		tmp = ext3_get_group_desc (sb, i, &bh2);
		if (tmp && le16_to_cpu(tmp->bg_free_inodes_count))
			gdp = tmp;
		else
		{
			/*
			 * Use a quadratic hash to find a group with a
			 * free inode
			 */
			for (j = 1; j < sb->u.ext3_sb.s_groups_count; j <<= 1) {
				i += j;
				if (i >= sb->u.ext3_sb.s_groups_count)
					i -= sb->u.ext3_sb.s_groups_count;
				tmp = ext3_get_group_desc (sb, i, &bh2);
				if (tmp &&
				    le16_to_cpu(tmp->bg_free_inodes_count)) {
					gdp = tmp;
					break;
				}
			}
		}
		if (!gdp) {
			/*
			 * That failed: try linear search for a free inode
			 */
			i = dir->u.ext3_i.i_block_group + 1;
			for (j = 2; j < sb->u.ext3_sb.s_groups_count; j++) {
				if (++i >= sb->u.ext3_sb.s_groups_count)
					i = 0;
				tmp = ext3_get_group_desc (sb, i, &bh2);
				if (tmp &&
				    le16_to_cpu(tmp->bg_free_inodes_count)) {
					gdp = tmp;
					break;
				}
			}
		}
	}

	err = -ENOSPC;
	if (!gdp)
		goto fail;

	err = -EIO;
	bitmap_nr = load_inode_bitmap (sb, i);
	if (bitmap_nr < 0)
		goto fail;

	bh = sb->u.ext3_sb.s_inode_bitmap[bitmap_nr];

	if ((j = ext3_find_first_zero_bit ((unsigned long *) bh->b_data,
				      EXT3_INODES_PER_GROUP(sb))) <
	    EXT3_INODES_PER_GROUP(sb)) {
		BUFFER_TRACE(bh, "get_write_access");
		err = ext3_journal_get_write_access(handle, bh);
		if (err) goto fail;
		
		if (ext3_set_bit (j, bh->b_data)) {
			ext3_error (sb, "ext3_new_inode",
				      "bit already set for inode %d", j);
			goto repeat;
		}
		BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
		err = ext3_journal_dirty_metadata(handle, bh);
		if (err) goto fail;
	} else {
		if (le16_to_cpu(gdp->bg_free_inodes_count) != 0) {
			ext3_error (sb, "ext3_new_inode",
				    "Free inodes count corrupted in group %d",
				    i);
			/* Is it really ENOSPC? */
			err = -ENOSPC;
			if (sb->s_flags & MS_RDONLY)
				goto fail;

			BUFFER_TRACE(bh2, "get_write_access");
			err = ext3_journal_get_write_access(handle, bh2);
			if (err) goto fail;
			gdp->bg_free_inodes_count = 0;
			BUFFER_TRACE(bh2, "call ext3_journal_dirty_metadata");
			err = ext3_journal_dirty_metadata(handle, bh2);
			if (err) goto fail;
		}
		goto repeat;
	}
	j += i * EXT3_INODES_PER_GROUP(sb) + 1;
	if (j < EXT3_FIRST_INO(sb) || j > le32_to_cpu(es->s_inodes_count)) {
		ext3_error (sb, "ext3_new_inode",
			    "reserved inode or inode > inodes count - "
			    "block_group = %d,inode=%d", i, j);
		err = -EIO;
		goto fail;
	}

	BUFFER_TRACE(bh2, "get_write_access");
	err = ext3_journal_get_write_access(handle, bh2);
	if (err) goto fail;
	gdp->bg_free_inodes_count =
		cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) - 1);
	if (S_ISDIR(mode))
		gdp->bg_used_dirs_count =
			cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) + 1);
	BUFFER_TRACE(bh2, "call ext3_journal_dirty_metadata");
	err = ext3_journal_dirty_metadata(handle, bh2);
	if (err) goto fail;
	
	BUFFER_TRACE(sb->u.ext3_sb.s_sbh, "get_write_access");
	err = ext3_journal_get_write_access(handle, sb->u.ext3_sb.s_sbh);
	if (err) goto fail;
	es->s_free_inodes_count =
		cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) - 1);
	BUFFER_TRACE(sb->u.ext3_sb.s_sbh, "call ext3_journal_dirty_metadata");
	err = ext3_journal_dirty_metadata(handle, sb->u.ext3_sb.s_sbh);
	sb->s_dirt = 1;
	if (err) goto fail;

	inode->i_uid = current->fsuid;
	if (test_opt (sb, GRPID))
		inode->i_gid = dir->i_gid;
	else if (dir->i_mode & S_ISGID) {
		inode->i_gid = dir->i_gid;
		if (S_ISDIR(mode))
			mode |= S_ISGID;
	} else
		inode->i_gid = current->fsgid;
	inode->i_mode = mode;

	inode->i_ino = j;
	/* This is the optimal IO size (for stat), not the fs block size */
	inode->i_blksize = PAGE_SIZE;
	inode->i_blocks = 0;
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	inode->u.ext3_i.i_flags = dir->u.ext3_i.i_flags & ~EXT3_INDEX_FL;
	if (S_ISLNK(mode))
		inode->u.ext3_i.i_flags &= ~(EXT3_IMMUTABLE_FL|EXT3_APPEND_FL);
#ifdef EXT3_FRAGMENTS
	inode->u.ext3_i.i_faddr = 0;
	inode->u.ext3_i.i_frag_no = 0;
	inode->u.ext3_i.i_frag_size = 0;
#endif
	inode->u.ext3_i.i_file_acl = 0;
	inode->u.ext3_i.i_dir_acl = 0;
	inode->u.ext3_i.i_dtime = 0;
	INIT_LIST_HEAD(&inode->u.ext3_i.i_orphan);
#ifdef EXT3_PREALLOCATE
	inode->u.ext3_i.i_prealloc_count = 0;
#endif
	inode->u.ext3_i.i_block_group = i;
	
	if (inode->u.ext3_i.i_flags & EXT3_SYNC_FL)
		inode->i_flags |= S_SYNC;
	if (IS_SYNC(inode))
		handle->h_sync = 1;
	insert_inode_hash(inode);
	inode->i_generation = sb->u.ext3_sb.s_next_generation++;

	inode->u.ext3_i.i_state = EXT3_STATE_NEW;
	err = ext3_mark_inode_dirty(handle, inode);
	if (err) goto fail;
	
	unlock_super (sb);
	if(DQUOT_ALLOC_INODE(inode)) {
		DQUOT_DROP(inode);
		inode->i_flags |= S_NOQUOTA;
		inode->i_nlink = 0;
		iput(inode);
		return ERR_PTR(-EDQUOT);
	}
	ext3_debug ("allocating inode %lu\n", inode->i_ino);
	return inode;

fail:
	unlock_super(sb);
	iput(inode);
	ext3_std_error(sb, err);
	return ERR_PTR(err);
}

/* Verify that we are loading a valid orphan from disk */
struct inode *ext3_orphan_get (struct super_block * sb, ino_t ino)
{
	ino_t max_ino = le32_to_cpu(EXT3_SB(sb)->s_es->s_inodes_count);
	unsigned long block_group;
	int bit;
	int bitmap_nr;
	struct buffer_head *bh;
	struct inode *inode = NULL;
	
	/* Error cases - e2fsck has already cleaned up for us */
	if (ino > max_ino) {
		ext3_warning(sb, __FUNCTION__,
			     "bad orphan ino %ld!  e2fsck was run?\n", ino);
		return NULL;
	}

	block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb);
	bit = (ino - 1) % EXT3_INODES_PER_GROUP(sb);
	if ((bitmap_nr = load_inode_bitmap(sb, block_group)) < 0 ||
	    !(bh = EXT3_SB(sb)->s_inode_bitmap[bitmap_nr])) {
		ext3_warning(sb, __FUNCTION__,
			     "inode bitmap error for orphan %ld\n", ino);
		return NULL;
	}

	/* Having the inode bit set should be a 100% indicator that this
	 * is a valid orphan (no e2fsck run on fs).  Orphans also include
	 * inodes that were being truncated, so we can't check i_nlink==0.
	 */
	if (!ext3_test_bit(bit, bh->b_data) || !(inode = iget(sb, ino)) ||
	    is_bad_inode(inode) || NEXT_ORPHAN(inode) > max_ino) {
		ext3_warning(sb, __FUNCTION__,
			     "bad orphan inode %ld!  e2fsck was run?\n", ino);
		printk(KERN_NOTICE "ext3_test_bit(bit=%d, block=%ld) = %d\n",
		       bit, bh->b_blocknr, ext3_test_bit(bit, bh->b_data));
		printk(KERN_NOTICE "inode=%p\n", inode);
		if (inode) {
			printk(KERN_NOTICE "is_bad_inode(inode)=%d\n",
			       is_bad_inode(inode));
			printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%d\n",
			       NEXT_ORPHAN(inode));
			printk(KERN_NOTICE "max_ino=%ld\n", max_ino);
		}
		/* Avoid freeing blocks if we got a bad deleted inode */
		if (inode && inode->i_nlink == 0)
			inode->i_blocks = 0;
		iput(inode);
		return NULL;
	}

	return inode;
}

unsigned long ext3_count_free_inodes (struct super_block * sb)
{
#ifdef EXT3FS_DEBUG
	struct ext3_super_block * es;
	unsigned long desc_count, bitmap_count, x;
	int bitmap_nr;
	struct ext3_group_desc * gdp;
	int i;

	lock_super (sb);
	es = sb->u.ext3_sb.s_es;
	desc_count = 0;
	bitmap_count = 0;
	gdp = NULL;
	for (i = 0; i < sb->u.ext3_sb.s_groups_count; i++) {
		gdp = ext3_get_group_desc (sb, i, NULL);
		if (!gdp)
			continue;
		desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
		bitmap_nr = load_inode_bitmap (sb, i);
		if (bitmap_nr < 0)
			continue;

		x = ext3_count_free (sb->u.ext3_sb.s_inode_bitmap[bitmap_nr],
				     EXT3_INODES_PER_GROUP(sb) / 8);
		printk ("group %d: stored = %d, counted = %lu\n",
			i, le16_to_cpu(gdp->bg_free_inodes_count), x);
		bitmap_count += x;
	}
	printk("ext3_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
		le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
	unlock_super (sb);
	return desc_count;
#else
	return le32_to_cpu(sb->u.ext3_sb.s_es->s_free_inodes_count);
#endif
}

#ifdef CONFIG_EXT3_CHECK
/* Called at mount-time, super-block is locked */
void ext3_check_inodes_bitmap (struct super_block * sb)
{
	struct ext3_super_block * es;
	unsigned long desc_count, bitmap_count, x;
	int bitmap_nr;
	struct ext3_group_desc * gdp;
	int i;

	es = sb->u.ext3_sb.s_es;
	desc_count = 0;
	bitmap_count = 0;
	gdp = NULL;
	for (i = 0; i < sb->u.ext3_sb.s_groups_count; i++) {
		gdp = ext3_get_group_desc (sb, i, NULL);
		if (!gdp)
			continue;
		desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
		bitmap_nr = load_inode_bitmap (sb, i);
		if (bitmap_nr < 0)
			continue;

		x = ext3_count_free (sb->u.ext3_sb.s_inode_bitmap[bitmap_nr],
				     EXT3_INODES_PER_GROUP(sb) / 8);
		if (le16_to_cpu(gdp->bg_free_inodes_count) != x)
			ext3_error (sb, "ext3_check_inodes_bitmap",
				    "Wrong free inodes count in group %d, "
				    "stored = %d, counted = %lu", i,
				    le16_to_cpu(gdp->bg_free_inodes_count), x);
		bitmap_count += x;
	}
	if (le32_to_cpu(es->s_free_inodes_count) != bitmap_count)
		ext3_error (sb, "ext3_check_inodes_bitmap",
			    "Wrong free inodes count in super block, "
			    "stored = %lu, counted = %lu",
			    (unsigned long)le32_to_cpu(es->s_free_inodes_count),
			    bitmap_count);
}
#endif