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/*

 *  linux/fs/ext3/ialloc.c

 *

 * Copyright (C) 1992, 1993, 1994, 1995

 * Remy Card (card@masi.ibp.fr)

 * Laboratoire MASI - Institut Blaise Pascal

 * Universite Pierre et Marie Curie (Paris VI)

 *

 *  BSD ufs-inspired inode and directory allocation by

 *  Stephen Tweedie (sct@redhat.com), 1993

 *  Big-endian to little-endian byte-swapping/bitmaps by

 *        David S. Miller (davem@caip.rutgers.edu), 1995

 */

#include <linux/sched.h>

#include <linux/fs.h>

#include <linux/jbd.h>

#include <linux/ext3_fs.h>

#include <linux/ext3_jbd.h>

#include <linux/stat.h>

#include <linux/string.h>

#include <linux/locks.h>

#include <linux/quotaops.h>

#include <asm/bitops.h>

#include <asm/byteorder.h>

/*

 * ialloc.c contains the inodes allocation and deallocation routines

 */

/*

 * The free inodes are managed by bitmaps.  A file system contains several

 * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap

 * block for inodes, N blocks for the inode table and data blocks.

 *

 * The file system contains group descriptors which are located after the

 * super block.  Each descriptor contains the number of the bitmap block and

 * the free blocks count in the block.  The descriptors are loaded in memory

 * when a file system is mounted (see ext3_read_super).

 */

/*

 * Read the inode allocation bitmap for a given block_group, reading

 * into the specified slot in the superblock's bitmap cache.

 *

 * Return >=0 on success or a -ve error code.

 */

static int read_inode_bitmap (struct super_block * sb,

                               unsigned long block_group,

                               unsigned int bitmap_nr)

{

        struct ext3_group_desc * gdp;

        struct buffer_head * bh = NULL;

        int retval = 0;

        gdp = ext3_get_group_desc (sb, block_group, NULL);

        if (!gdp) {

                retval = -EIO;

                goto error_out;

        }

        bh = sb_bread(sb, le32_to_cpu(gdp->bg_inode_bitmap));

        if (!bh) {

                ext3_error (sb, "read_inode_bitmap",

                            "Cannot read inode bitmap - "

                            "block_group = %lu, inode_bitmap = %u",

                            block_group, gdp->bg_inode_bitmap);

                retval = -EIO;

        }

        /*

         * On IO error, just leave a zero in the superblock's block pointer for

         * this group.  The IO will be retried next time.

         */

error_out:

        sb->u.ext3_sb.s_inode_bitmap_number[bitmap_nr] = block_group;

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

        return retval;

}

/*

 * load_inode_bitmap loads the inode bitmap for a blocks group

 *

 * It maintains a cache for the last bitmaps loaded.  This cache is managed

 * with a LRU algorithm.

 *

 * Notes:

 * 1/ There is one cache per mounted file system.

 * 2/ If the file system contains less than EXT3_MAX_GROUP_LOADED groups,

 *    this function reads the bitmap without maintaining a LRU cache.

 *

 * Return the slot used to store the bitmap, or a -ve error code.

 */

static int load_inode_bitmap (struct super_block * sb,

                              unsigned int block_group)

{

        struct ext3_sb_info *sbi = EXT3_SB(sb);

        unsigned long inode_bitmap_number;

        struct buffer_head * inode_bitmap;

        int i, j, retval = 0;

        if (block_group >= sbi->s_groups_count)

                ext3_panic (sb, "load_inode_bitmap",

                            "block_group >= groups_count - "

                            "block_group = %d, groups_count = %lu",

                            block_group, sbi->s_groups_count);

        if (sbi->s_loaded_inode_bitmaps > 0 &&

            sbi->s_inode_bitmap_number[0] == block_group &&

            sbi->s_inode_bitmap[0] != NULL)

                return 0;

        if (sbi->s_groups_count <= EXT3_MAX_GROUP_LOADED) {

                if (sbi->s_inode_bitmap[block_group]) {

                        if (sbi->s_inode_bitmap_number[block_group] !=

                                                block_group)

                                ext3_panic(sb, "load_inode_bitmap",

                                        "block_group != inode_bitmap_number");

                        return block_group;

                }

                retval = read_inode_bitmap(sb, block_group, block_group);

                if (retval < 0)

                        return retval;

                return block_group;

        }

        for (i = 0; i < sbi->s_loaded_inode_bitmaps &&

                    sbi->s_inode_bitmap_number[i] != block_group; i++)

                /* do nothing */;

        if (i < sbi->s_loaded_inode_bitmaps &&

            sbi->s_inode_bitmap_number[i] == block_group) {

                inode_bitmap_number = sbi->s_inode_bitmap_number[i];

                inode_bitmap = sbi->s_inode_bitmap[i];

                for (j = i; j > 0; j--) {

                        sbi->s_inode_bitmap_number[j] =

                                sbi->s_inode_bitmap_number[j - 1];

                        sbi->s_inode_bitmap[j] = sbi->s_inode_bitmap[j - 1];

                }

                sbi->s_inode_bitmap_number[0] = inode_bitmap_number;

                sbi->s_inode_bitmap[0] = inode_bitmap;

                /*

                 * There's still one special case here --- if inode_bitmap == 0

                 * then our last attempt to read the bitmap failed and we have

                 * just ended up caching that failure.  Try again to read it.

                 */

                if (!inode_bitmap)

                        retval = read_inode_bitmap (sb, block_group, 0);

        } else {

                if (sbi->s_loaded_inode_bitmaps < EXT3_MAX_GROUP_LOADED)

                        sbi->s_loaded_inode_bitmaps++;

                else

                        brelse(sbi->s_inode_bitmap[EXT3_MAX_GROUP_LOADED - 1]);

                for (j = sbi->s_loaded_inode_bitmaps - 1; j > 0; j--) {

                        sbi->s_inode_bitmap_number[j] =

                                sbi->s_inode_bitmap_number[j - 1];

                        sbi->s_inode_bitmap[j] = sbi->s_inode_bitmap[j - 1];

                }

                retval = read_inode_bitmap (sb, block_group, 0);

        }

        return retval;

}

/*

 * NOTE! When we get the inode, we're the only people

 * that have access to it, and as such there are no

 * race conditions we have to worry about. The inode

 * is not on the hash-lists, and it cannot be reached

 * through the filesystem because the directory entry

 * has been deleted earlier.

 *

 * HOWEVER: we must make sure that we get no aliases,

 * which means that we have to call "clear_inode()"

 * _before_ we mark the inode not in use in the inode

 * bitmaps. Otherwise a newly created file might use

 * the same inode number (not actually the same pointer

 * though), and then we'd have two inodes sharing the

 * same inode number and space on the harddisk.

 */

void ext3_free_inode (handle_t *handle, struct inode * inode)

{

        struct super_block * sb = inode->i_sb;

        int is_directory;

        unsigned long ino;

        struct buffer_head * bh;

        struct buffer_head * bh2;

        unsigned long block_group;

        unsigned long bit;

        int bitmap_nr;

        struct ext3_group_desc * gdp;

        struct ext3_super_block * es;

        int fatal = 0, err;

        if (!inode->i_dev) {

                printk ("ext3_free_inode: inode has no device\n");

                return;

        }

        if (atomic_read(&inode->i_count) > 1) {

                printk ("ext3_free_inode: inode has count=%d\n",

                                        atomic_read(&inode->i_count));

                return;

        }

        if (inode->i_nlink) {

                printk ("ext3_free_inode: inode has nlink=%d\n",

                        inode->i_nlink);

                return;

        }

        if (!sb) {

                printk("ext3_free_inode: inode on nonexistent device\n");

                return;

        }

        ino = inode->i_ino;

        ext3_debug ("freeing inode %lu\n", ino);

        /*

         * Note: we must free any quota before locking the superblock,

         * as writing the quota to disk may need the lock as well.

         */

        DQUOT_INIT(inode);

        DQUOT_FREE_INODE(inode);

        DQUOT_DROP(inode);

        is_directory = S_ISDIR(inode->i_mode);

        /* Do this BEFORE marking the inode not in use or returning an error */

        clear_inode (inode);

        lock_super (sb);

        es = sb->u.ext3_sb.s_es;

        if (ino < EXT3_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {

                ext3_error (sb, "ext3_free_inode",

                            "reserved or nonexistent inode %lu", ino);

                goto error_return;

        }

        block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb);

        bit = (ino - 1) % EXT3_INODES_PER_GROUP(sb);

        bitmap_nr = load_inode_bitmap (sb, block_group);

        if (bitmap_nr < 0)

                goto error_return;

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

        BUFFER_TRACE(bh, "get_write_access");

        fatal = ext3_journal_get_write_access(handle, bh);

        if (fatal)

                goto error_return;

        /* Ok, now we can actually update the inode bitmaps.. */

        if (!ext3_clear_bit (bit, bh->b_data))

                ext3_error (sb, "ext3_free_inode",

                              "bit already cleared for inode %lu", ino);

        else {

                gdp = ext3_get_group_desc (sb, block_group, &bh2);

                BUFFER_TRACE(bh2, "get_write_access");

                fatal = ext3_journal_get_write_access(handle, bh2);

                if (fatal) goto error_return;

                BUFFER_TRACE(sb->u.ext3_sb.s_sbh, "get write access");

                fatal = ext3_journal_get_write_access(handle, sb->u.ext3_sb.s_sbh);

                if (fatal) goto error_return;

                if (gdp) {

                        gdp->bg_free_inodes_count = cpu_to_le16(

                                le16_to_cpu(gdp->bg_free_inodes_count) + 1);

                        if (is_directory)

                                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 (!fatal) fatal = err;

                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);

                if (!fatal) fatal = err;

        }

        BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");

        err = ext3_journal_dirty_metadata(handle, bh);

        if (!fatal)

                fatal = err;

        sb->s_dirt = 1;

error_return:

        ext3_std_error(sb, fatal);

        unlock_super(sb);

}

/*

 * There are two policies for allocating an inode.  If the new inode is

 * a directory, then a forward search is made for a block group with both

 * free space and a low directory-to-inode ratio; if that fails, then of

 * the groups with above-average free space, that group with the fewest

 * directories already is chosen.

 *

 * For other inodes, search forward from the parent directory's block

 * group to find a free inode.

 */

struct inode * ext3_new_inode (handle_t *handle,

                                const struct inode * dir, int mode)

{

        struct super_block * sb;

        struct buffer_head * bh;

        struct buffer_head * bh2;

        int i, j, avefreei;

        struct inode * inode;

        int bitmap_nr;

        struct ext3_group_desc * gdp;

        struct ext3_group_desc * tmp;

        struct ext3_super_block * es;

        int err = 0;

        /* Cannot create files in a deleted directory */

        if (!dir || !dir->i_nlink)

                return ERR_PTR(-EPERM);

        sb = dir->i_sb;

        inode = new_inode(sb);

        if (!inode)

                return ERR_PTR(-ENOMEM);

        init_rwsem(&inode->u.ext3_i.truncate_sem);

        lock_super (sb);

        es = sb->u.ext3_sb.s_es;

repeat:

        gdp = NULL;

        i = 0;

        if (S_ISDIR(mode)) {

                avefreei = le32_to_cpu(es->s_free_inodes_count) /

                        sb->u.ext3_sb.s_groups_count;

                if (!gdp) {

                        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 out;

        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;

        ext3_set_inode_flags(inode);

        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:

        ext3_std_error(sb, err);

out:

        unlock_super(sb);

        iput(inode);

        return ERR_PTR(err);

}

/* Verify that we are loading a valid orphan from disk */

struct inode *ext3_orphan_get(struct super_block *sb, unsigned long ino)

{

        unsigned long 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 %lu!  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 %lu\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 %lu!  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)=%u\n",

                               NEXT_ORPHAN(inode));

                        printk(KERN_NOTICE "max_ino=%lu\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],