1 files changed, 768 insertions, 0 deletions

diff --git a/e2fsprogs/ext2fs/inode.c b/e2fsprogs/ext2fs/inode.c
new file mode 100644
index 000000000..2ff9fe6ca
--- /dev/null
+++ b/e2fsprogs/ext2fs/inode.c
@@ -0,0 +1,768 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * inode.c --- utility routines to read and write inodes
+ *
+ * Copyright (C) 1993, 1994, 1995, 1996, 1997 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fsP.h"
+#include "e2image.h"
+
+struct ext2_struct_inode_scan {
+        errcode_t               magic;
+        ext2_filsys             fs;
+        ext2_ino_t              current_inode;
+        blk_t                   current_block;
+        dgrp_t                  current_group;
+        ext2_ino_t              inodes_left;
+        blk_t                   blocks_left;
+        dgrp_t                  groups_left;
+        blk_t                   inode_buffer_blocks;
+        char *                  inode_buffer;
+        int                     inode_size;
+        char *                  ptr;
+        int                     bytes_left;
+        char                    *temp_buffer;
+        errcode_t               (*done_group)(ext2_filsys fs,
+                                              dgrp_t group,
+                                              void * priv_data);
+        void *                  done_group_data;
+        int                     bad_block_ptr;
+        int                     scan_flags;
+        int                     reserved[6];
+};
+
+/*
+ * This routine flushes the icache, if it exists.
+ */
+errcode_t ext2fs_flush_icache(ext2_filsys fs)
+{
+        int     i;
+
+        if (!fs->icache)
+                return 0;
+
+        for (i=0; i < fs->icache->cache_size; i++)
+                fs->icache->cache[i].ino = 0;
+
+        fs->icache->buffer_blk = 0;
+        return 0;
+}
+
+static errcode_t create_icache(ext2_filsys fs)
+{
+        errcode_t       retval;
+
+        if (fs->icache)
+                return 0;
+        retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache), &fs->icache);
+        if (retval)
+                return retval;
+
+        memset(fs->icache, 0, sizeof(struct ext2_inode_cache));
+        retval = ext2fs_get_mem(fs->blocksize, &fs->icache->buffer);
+        if (retval) {
+                ext2fs_free_mem(&fs->icache);
+                return retval;
+        }
+        fs->icache->buffer_blk = 0;
+        fs->icache->cache_last = -1;
+        fs->icache->cache_size = 4;
+        fs->icache->refcount = 1;
+        retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache_ent)
+                                * fs->icache->cache_size,
+                                &fs->icache->cache);
+        if (retval) {
+                ext2fs_free_mem(&fs->icache->buffer);
+                ext2fs_free_mem(&fs->icache);
+                return retval;
+        }
+        ext2fs_flush_icache(fs);
+        return 0;
+}
+
+errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks,
+                                 ext2_inode_scan *ret_scan)
+{
+        ext2_inode_scan scan;
+        errcode_t       retval;
+        errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks);
+
+        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+        /*
+         * If fs->badblocks isn't set, then set it --- since the inode
+         * scanning functions require it.
+         */
+        if (fs->badblocks == 0) {
+                /*
+                 * Temporarly save fs->get_blocks and set it to zero,
+                 * for compatibility with old e2fsck's.
+                 */
+                save_get_blocks = fs->get_blocks;
+                fs->get_blocks = 0;
+                retval = ext2fs_read_bb_inode(fs, &fs->badblocks);
+                if (retval) {
+                        ext2fs_badblocks_list_free(fs->badblocks);
+                        fs->badblocks = 0;
+                }
+                fs->get_blocks = save_get_blocks;
+        }
+
+        retval = ext2fs_get_mem(sizeof(struct ext2_struct_inode_scan), &scan);
+        if (retval)
+                return retval;
+        memset(scan, 0, sizeof(struct ext2_struct_inode_scan));
+
+        scan->magic = EXT2_ET_MAGIC_INODE_SCAN;
+        scan->fs = fs;
+        scan->inode_size = EXT2_INODE_SIZE(fs->super);
+        scan->bytes_left = 0;
+        scan->current_group = 0;
+        scan->groups_left = fs->group_desc_count - 1;
+        scan->inode_buffer_blocks = buffer_blocks ? buffer_blocks : 8;
+        scan->current_block = scan->fs->
+                group_desc[scan->current_group].bg_inode_table;
+        scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super);
+        scan->blocks_left = scan->fs->inode_blocks_per_group;
+        retval = ext2fs_get_mem((size_t) (scan->inode_buffer_blocks *
+                                          fs->blocksize),
+                                &scan->inode_buffer);
+        scan->done_group = 0;
+        scan->done_group_data = 0;
+        scan->bad_block_ptr = 0;
+        if (retval) {
+                ext2fs_free_mem(&scan);
+                return retval;
+        }
+        retval = ext2fs_get_mem(scan->inode_size, &scan->temp_buffer);
+        if (retval) {
+                ext2fs_free_mem(&scan->inode_buffer);
+                ext2fs_free_mem(&scan);
+                return retval;
+        }
+        if (scan->fs->badblocks && scan->fs->badblocks->num)
+                scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS;
+        *ret_scan = scan;
+        return 0;
+}
+
+void ext2fs_close_inode_scan(ext2_inode_scan scan)
+{
+        if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
+                return;
+
+        ext2fs_free_mem(&scan->inode_buffer);
+        scan->inode_buffer = NULL;
+        ext2fs_free_mem(&scan->temp_buffer);
+        scan->temp_buffer = NULL;
+        ext2fs_free_mem(&scan);
+        return;
+}
+
+void ext2fs_set_inode_callback(ext2_inode_scan scan,
+                               errcode_t (*done_group)(ext2_filsys fs,
+                                                       dgrp_t group,
+                                                       void * priv_data),
+                               void *done_group_data)
+{
+        if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
+                return;
+
+        scan->done_group = done_group;
+        scan->done_group_data = done_group_data;
+}
+
+int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags,
+                            int clear_flags)
+{
+        int     old_flags;
+
+        if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
+                return 0;
+
+        old_flags = scan->scan_flags;
+        scan->scan_flags &= ~clear_flags;
+        scan->scan_flags |= set_flags;
+        return old_flags;
+}
+
+/*
+ * This function is called by ext2fs_get_next_inode when it needs to
+ * get ready to read in a new blockgroup.
+ */
+static errcode_t get_next_blockgroup(ext2_inode_scan scan)
+{
+        scan->current_group++;
+        scan->groups_left--;
+
+        scan->current_block = scan->fs->
+                group_desc[scan->current_group].bg_inode_table;
+
+        scan->current_inode = scan->current_group *
+                EXT2_INODES_PER_GROUP(scan->fs->super);
+
+        scan->bytes_left = 0;
+        scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super);
+        scan->blocks_left = scan->fs->inode_blocks_per_group;
+        return 0;
+}
+
+errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan,
+                                            int group)
+{
+        scan->current_group = group - 1;
+        scan->groups_left = scan->fs->group_desc_count - group;
+        return get_next_blockgroup(scan);
+}
+
+/*
+ * This function is called by get_next_blocks() to check for bad
+ * blocks in the inode table.
+ *
+ * This function assumes that badblocks_list->list is sorted in
+ * increasing order.
+ */
+static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan,
+                                            blk_t *num_blocks)
+{
+        blk_t   blk = scan->current_block;
+        badblocks_list  bb = scan->fs->badblocks;
+
+        /*
+         * If the inode table is missing, then obviously there are no
+         * bad blocks.  :-)
+         */
+        if (blk == 0)
+                return 0;
+
+        /*
+         * If the current block is greater than the bad block listed
+         * in the bad block list, then advance the pointer until this
+         * is no longer the case.  If we run out of bad blocks, then
+         * we don't need to do any more checking!
+         */
+        while (blk > bb->list[scan->bad_block_ptr]) {
+                if (++scan->bad_block_ptr >= bb->num) {
+                        scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS;
+                        return 0;
+                }
+        }
+
+        /*
+         * If the current block is equal to the bad block listed in
+         * the bad block list, then handle that one block specially.
+         * (We could try to handle runs of bad blocks, but that
+         * only increases CPU efficiency by a small amount, at the
+         * expense of a huge expense of code complexity, and for an
+         * uncommon case at that.)
+         */
+        if (blk == bb->list[scan->bad_block_ptr]) {
+                scan->scan_flags |= EXT2_SF_BAD_INODE_BLK;
+                *num_blocks = 1;
+                if (++scan->bad_block_ptr >= bb->num)
+                        scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS;
+                return 0;
+        }
+
+        /*
+         * If there is a bad block in the range that we're about to
+         * read in, adjust the number of blocks to read so that we we
+         * don't read in the bad block.  (Then the next block to read
+         * will be the bad block, which is handled in the above case.)
+         */
+        if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr])
+                *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk);
+
+        return 0;
+}
+
+/*
+ * This function is called by ext2fs_get_next_inode when it needs to
+ * read in more blocks from the current blockgroup's inode table.
+ */
+static errcode_t get_next_blocks(ext2_inode_scan scan)
+{
+        blk_t           num_blocks;
+        errcode_t       retval;
+
+        /*
+         * Figure out how many blocks to read; we read at most
+         * inode_buffer_blocks, and perhaps less if there aren't that
+         * many blocks left to read.
+         */
+        num_blocks = scan->inode_buffer_blocks;
+        if (num_blocks > scan->blocks_left)
+                num_blocks = scan->blocks_left;
+
+        /*
+         * If the past block "read" was a bad block, then mark the
+         * left-over extra bytes as also being bad.
+         */
+        if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) {
+                if (scan->bytes_left)
+                        scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES;
+                scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK;
+        }
+
+        /*
+         * Do inode bad block processing, if necessary.
+         */
+        if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) {
+                retval = check_for_inode_bad_blocks(scan, &num_blocks);
+                if (retval)
+                        return retval;
+        }
+
+        if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) ||
+            (scan->current_block == 0)) {
+                memset(scan->inode_buffer, 0,
+                       (size_t) num_blocks * scan->fs->blocksize);
+        } else {
+                retval = io_channel_read_blk(scan->fs->io,
+                                             scan->current_block,
+                                             (int) num_blocks,
+                                             scan->inode_buffer);
+                if (retval)
+                        return EXT2_ET_NEXT_INODE_READ;
+        }
+        scan->ptr = scan->inode_buffer;
+        scan->bytes_left = num_blocks * scan->fs->blocksize;
+
+        scan->blocks_left -= num_blocks;
+        if (scan->current_block)
+                scan->current_block += num_blocks;
+        return 0;
+}
+
+errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino,
+                                     struct ext2_inode *inode, int bufsize)
+{
+        errcode_t       retval;
+        int             extra_bytes = 0;
+
+        EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN);
+
+        /*
+         * Do we need to start reading a new block group?
+         */
+        if (scan->inodes_left <= 0) {
+        force_new_group:
+                if (scan->done_group) {
+                        retval = (scan->done_group)
+                                (scan->fs, scan->current_group,
+                                 scan->done_group_data);
+                        if (retval)
+                                return retval;
+                }
+                if (scan->groups_left <= 0) {
+                        *ino = 0;
+                        return 0;
+                }
+                retval = get_next_blockgroup(scan);
+                if (retval)
+                        return retval;
+        }
+        /*
+         * This is done outside the above if statement so that the
+         * check can be done for block group #0.
+         */
+        if (scan->current_block == 0) {
+                if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) {
+                        goto force_new_group;
+                } else
+                        return EXT2_ET_MISSING_INODE_TABLE;
+        }
+
+
+        /*
+         * Have we run out of space in the inode buffer?  If so, we
+         * need to read in more blocks.
+         */
+        if (scan->bytes_left < scan->inode_size) {
+                memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left);
+                extra_bytes = scan->bytes_left;
+
+                retval = get_next_blocks(scan);
+                if (retval)
+                        return retval;
+#if 0
+                /*
+                 * XXX test  Need check for used inode somehow.
+                 * (Note: this is hard.)
+                 */
+                if (is_empty_scan(scan))
+                        goto force_new_group;
+#endif
+        }
+
+        retval = 0;
+        if (extra_bytes) {
+                memcpy(scan->temp_buffer+extra_bytes, scan->ptr,
+                       scan->inode_size - extra_bytes);
+                scan->ptr += scan->inode_size - extra_bytes;
+                scan->bytes_left -= scan->inode_size - extra_bytes;
+
+#if BB_BIG_ENDIAN
+                if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+                    (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
+                        ext2fs_swap_inode_full(scan->fs,
+                                (struct ext2_inode_large *) inode,
+                                (struct ext2_inode_large *) scan->temp_buffer,
+                                0, bufsize);
+                else
+#endif
+                        *inode = *((struct ext2_inode *) scan->temp_buffer);
+                if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES)
+                        retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE;
+                scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES;
+        } else {
+#if BB_BIG_ENDIAN
+                if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+                    (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
+                        ext2fs_swap_inode_full(scan->fs,
+                                (struct ext2_inode_large *) inode,
+                                (struct ext2_inode_large *) scan->ptr,
+                                0, bufsize);
+                else
+#endif
+                        memcpy(inode, scan->ptr, bufsize);
+                scan->ptr += scan->inode_size;
+                scan->bytes_left -= scan->inode_size;
+                if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK)
+                        retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE;
+        }
+
+        scan->inodes_left--;
+        scan->current_inode++;
+        *ino = scan->current_inode;
+        return retval;
+}
+
+errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino,
+                                struct ext2_inode *inode)
+{
+        return ext2fs_get_next_inode_full(scan, ino, inode,
+                                                sizeof(struct ext2_inode));
+}
+
+/*
+ * Functions to read and write a single inode.
+ */
+errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino,
+                                 struct ext2_inode * inode, int bufsize)
+{
+        unsigned long   group, block, block_nr, offset;
+        char            *ptr;
+        errcode_t       retval;
+        int             clen, i, inodes_per_block, length;
+        io_channel      io;
+
+        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+        /* Check to see if user has an override function */
+        if (fs->read_inode) {
+                retval = (fs->read_inode)(fs, ino, inode);
+                if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
+                        return retval;
+        }
+        /* Create inode cache if not present */
+        if (!fs->icache) {
+                retval = create_icache(fs);
+                if (retval)
+                        return retval;
+        }
+        /* Check to see if it's in the inode cache */
+        if (bufsize == sizeof(struct ext2_inode)) {
+                /* only old good inode can be retrieve from the cache */
+                for (i=0; i < fs->icache->cache_size; i++) {
+                        if (fs->icache->cache[i].ino == ino) {
+                                *inode = fs->icache->cache[i].inode;
+                                return 0;
+                        }
+                }
+        }
+        if ((ino == 0) || (ino > fs->super->s_inodes_count))
+                return EXT2_ET_BAD_INODE_NUM;
+        if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
+                inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super);
+                block_nr = fs->image_header->offset_inode / fs->blocksize;
+                block_nr += (ino - 1) / inodes_per_block;
+                offset = ((ino - 1) % inodes_per_block) *
+                        EXT2_INODE_SIZE(fs->super);
+                io = fs->image_io;
+        } else {
+                group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super);
+                offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) *
+                        EXT2_INODE_SIZE(fs->super);
+                block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super);
+                if (!fs->group_desc[(unsigned)group].bg_inode_table)
+                        return EXT2_ET_MISSING_INODE_TABLE;
+                block_nr = fs->group_desc[(unsigned)group].bg_inode_table +
+                        block;
+                io = fs->io;
+        }
+        offset &= (EXT2_BLOCK_SIZE(fs->super) - 1);
+
+        length = EXT2_INODE_SIZE(fs->super);
+        if (bufsize < length)
+                length = bufsize;
+
+        ptr = (char *) inode;
+        while (length) {
+                clen = length;
+                if ((offset + length) > fs->blocksize)
+                        clen = fs->blocksize - offset;
+
+                if (block_nr != fs->icache->buffer_blk) {
+                        retval = io_channel_read_blk(io, block_nr, 1,
+                                                     fs->icache->buffer);
+                        if (retval)
+                                return retval;
+                        fs->icache->buffer_blk = block_nr;
+                }
+
+                memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset,
+                       clen);
+
+                offset = 0;
+                length -= clen;
+                ptr += clen;
+                block_nr++;
+        }
+
+#if BB_BIG_ENDIAN
+        if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+            (fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
+                ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) inode,
+                                       (struct ext2_inode_large *) inode,
+                                       0, length);
+#endif
+
+        /* Update the inode cache */
+        fs->icache->cache_last = (fs->icache->cache_last + 1) %
+                fs->icache->cache_size;
+        fs->icache->cache[fs->icache->cache_last].ino = ino;
+        fs->icache->cache[fs->icache->cache_last].inode = *inode;
+
+        return 0;
+}
+
+errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino,
+                            struct ext2_inode * inode)
+{
+        return ext2fs_read_inode_full(fs, ino, inode,
+                                        sizeof(struct ext2_inode));
+}
+
+errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino,
+                                  struct ext2_inode * inode, int bufsize)
+{
+        unsigned long group, block, block_nr, offset;
+        errcode_t retval = 0;
+        struct ext2_inode_large temp_inode, *w_inode;
+        char *ptr;
+        int clen, i, length;
+
+        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+        /* Check to see if user provided an override function */
+        if (fs->write_inode) {
+                retval = (fs->write_inode)(fs, ino, inode);
+                if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
+                        return retval;
+        }
+
+        /* Check to see if the inode cache needs to be updated */
+        if (fs->icache) {
+                for (i=0; i < fs->icache->cache_size; i++) {
+                        if (fs->icache->cache[i].ino == ino) {
+                                fs->icache->cache[i].inode = *inode;
+                                break;
+                        }
+                }
+        } else {
+                retval = create_icache(fs);
+                if (retval)
+                        return retval;
+        }
+
+        if (!(fs->flags & EXT2_FLAG_RW))
+                return EXT2_ET_RO_FILSYS;
+
+        if ((ino == 0) || (ino > fs->super->s_inodes_count))
+                return EXT2_ET_BAD_INODE_NUM;
+
+        length = bufsize;
+        if (length < EXT2_INODE_SIZE(fs->super))
+                length = EXT2_INODE_SIZE(fs->super);
+
+        if (length > (int) sizeof(struct ext2_inode_large)) {
+                w_inode = xmalloc(length);
+        } else
+                w_inode = &temp_inode;
+        memset(w_inode, 0, length);
+
+#if BB_BIG_ENDIAN
+        if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+            (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE))
+                ext2fs_swap_inode_full(fs, w_inode,
+                                       (struct ext2_inode_large *) inode,
+                                       1, bufsize);
+        else
+#endif
+                memcpy(w_inode, inode, bufsize);
+
+        group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super);
+        offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) *
+                EXT2_INODE_SIZE(fs->super);
+        block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super);
+        if (!fs->group_desc[(unsigned) group].bg_inode_table)
+                return EXT2_ET_MISSING_INODE_TABLE;
+        block_nr = fs->group_desc[(unsigned) group].bg_inode_table + block;
+
+        offset &= (EXT2_BLOCK_SIZE(fs->super) - 1);
+
+        length = EXT2_INODE_SIZE(fs->super);
+        if (length > bufsize)
+                length = bufsize;
+
+        ptr = (char *) w_inode;
+
+        while (length) {
+                clen = length;
+                if ((offset + length) > fs->blocksize)
+                        clen = fs->blocksize - offset;
+
+                if (fs->icache->buffer_blk != block_nr) {
+                        retval = io_channel_read_blk(fs->io, block_nr, 1,
+                                                     fs->icache->buffer);
+                        if (retval)
+                                goto errout;
+                        fs->icache->buffer_blk = block_nr;
+                }
+
+
+                memcpy((char *) fs->icache->buffer + (unsigned) offset,
+                       ptr, clen);
+
+                retval = io_channel_write_blk(fs->io, block_nr, 1,
+                                              fs->icache->buffer);
+                if (retval)
+                        goto errout;
+
+                offset = 0;
+                ptr += clen;
+                length -= clen;
+                block_nr++;
+        }
+
+        fs->flags |= EXT2_FLAG_CHANGED;
+errout:
+        if (w_inode && w_inode != &temp_inode)
+                free(w_inode);
+        return retval;
+}
+
+errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino,
+                             struct ext2_inode *inode)
+{
+        return ext2fs_write_inode_full(fs, ino, inode,
+                                       sizeof(struct ext2_inode));
+}
+
+/*
+ * This function should be called when writing a new inode.  It makes
+ * sure that extra part of large inodes is initialized properly.
+ */
+errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino,
+                                 struct ext2_inode *inode)
+{
+        struct ext2_inode       *buf;
+        int                     size = EXT2_INODE_SIZE(fs->super);
+        struct ext2_inode_large *large_inode;
+
+        if (size == sizeof(struct ext2_inode))
+                return ext2fs_write_inode_full(fs, ino, inode,
+                                               sizeof(struct ext2_inode));
+
+        buf = xmalloc(size);
+
+        memset(buf, 0, size);
+        *buf = *inode;
+
+        large_inode = (struct ext2_inode_large *) buf;
+        large_inode->i_extra_isize = sizeof(struct ext2_inode_large) -
+                EXT2_GOOD_OLD_INODE_SIZE;
+
+        return ext2fs_write_inode_full(fs, ino, buf, size);
+}
+
+
+errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks)
+{
+        struct ext2_inode       inode;
+        int                     i;
+        errcode_t               retval;
+
+        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+        if (ino > fs->super->s_inodes_count)
+                return EXT2_ET_BAD_INODE_NUM;
+
+        if (fs->get_blocks) {
+                if (!(*fs->get_blocks)(fs, ino, blocks))
+                        return 0;
+        }
+        retval = ext2fs_read_inode(fs, ino, &inode);
+        if (retval)
+                return retval;
+        for (i=0; i < EXT2_N_BLOCKS; i++)
+                blocks[i] = inode.i_block[i];
+        return 0;
+}
+
+errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino)
+{
+        struct  ext2_inode      inode;
+        errcode_t               retval;
+
+        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+        if (ino > fs->super->s_inodes_count)
+                return EXT2_ET_BAD_INODE_NUM;
+
+        if (fs->check_directory) {
+                retval = (fs->check_directory)(fs, ino);
+                if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
+                        return retval;
+        }
+        retval = ext2fs_read_inode(fs, ino, &inode);
+        if (retval)
+                return retval;
+        if (!LINUX_S_ISDIR(inode.i_mode))
+                return EXT2_ET_NO_DIRECTORY;
+        return 0;
+}
+