Adding upstream version 1.47.0.upstream/1.47.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3235 insertions, 0 deletions

diff --git a/resize/resize2fs.c b/resize/resize2fs.c
new file mode 100644
index 0000000..5eeb7d4
--- /dev/null
+++ b/resize/resize2fs.c
@@ -0,0 +1,3235 @@
+/*
+ * resize2fs.c --- ext2 main routine
+ *
+ * Copyright (C) 1997, 1998 by Theodore Ts'o and
+ * 	PowerQuest, Inc.
+ *
+ * Copyright (C) 1999, 2000 by Theodore Ts'o
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+/*
+ * Resizing a filesystem consists of the following phases:
+ *
+ *	1.  Adjust superblock and write out new parts of the inode
+ * 		table
+ * 	2.  Determine blocks which need to be relocated, and copy the
+ * 		contents of blocks from their old locations to the new ones.
+ * 	3.  Scan the inode table, doing the following:
+ * 		a.  If blocks have been moved, update the block
+ * 			pointers in the inodes and indirect blocks to
+ * 			point at the new block locations.
+ * 		b.  If parts of the inode table need to be evacuated,
+ * 			copy inodes from their old locations to their
+ * 			new ones.
+ * 		c.  If (b) needs to be done, note which blocks contain
+ * 			directory information, since we will need to
+ * 			update the directory information.
+ * 	4.  Update the directory blocks with the new inode locations.
+ * 	5.  Move the inode tables, if necessary.
+ */
+
+#include "config.h"
+#include "resize2fs.h"
+#include <time.h>
+
+#ifdef __linux__			/* Kludge for debugging */
+#define RESIZE2FS_DEBUG
+#endif
+
+static void fix_uninit_block_bitmaps(ext2_filsys fs);
+static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size);
+static errcode_t blocks_to_move(ext2_resize_t rfs);
+static errcode_t block_mover(ext2_resize_t rfs);
+static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
+static errcode_t inode_ref_fix(ext2_resize_t rfs);
+static errcode_t move_itables(ext2_resize_t rfs);
+static errcode_t fix_resize_inode(ext2_filsys fs);
+static errcode_t resize2fs_calculate_summary_stats(ext2_filsys fs);
+static errcode_t fix_sb_journal_backup(ext2_filsys fs);
+static errcode_t mark_table_blocks(ext2_filsys fs,
+				   ext2fs_block_bitmap bmap);
+static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs);
+static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
+						 ext2fs_block_bitmap meta_bmap);
+static errcode_t resize_group_descriptors(ext2_resize_t rfs, blk64_t new_size);
+static errcode_t move_bg_metadata(ext2_resize_t rfs);
+static errcode_t zero_high_bits_in_inodes(ext2_resize_t rfs);
+
+/*
+ * Some helper functions to check if a block is in a metadata area
+ */
+static inline int is_block_bm(ext2_filsys fs, unsigned int grp, blk64_t blk)
+{
+	return blk == ext2fs_block_bitmap_loc(fs, grp);
+}
+
+static inline int is_inode_bm(ext2_filsys fs, unsigned int grp, blk64_t blk)
+{
+	return blk == ext2fs_inode_bitmap_loc(fs, grp);
+}
+
+static int is_inode_tb(ext2_filsys fs, unsigned int grp, blk64_t blk)
+{
+	return blk >= ext2fs_inode_table_loc(fs, grp) &&
+	       blk < (ext2fs_inode_table_loc(fs, grp) +
+		      fs->inode_blocks_per_group);
+}
+
+/* Some bigalloc helper macros which are more succinct... */
+#define B2C(x)	EXT2FS_B2C(fs, (x))
+#define C2B(x)	EXT2FS_C2B(fs, (x))
+#define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
+#define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
+#define LT_CLSTR(x, y) (B2C(x) <  B2C(y))
+#define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
+#define GT_CLSTR(x, y) (B2C(x) >  B2C(y))
+
+static int lazy_itable_init;
+
+/*
+ * This is the top-level routine which does the dirty deed....
+ */
+errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
+	    errcode_t (*progress)(ext2_resize_t rfs, int pass,
+					  unsigned long cur,
+					  unsigned long max_val))
+{
+	ext2_resize_t	rfs;
+	errcode_t	retval;
+	struct resource_track	rtrack, overall_track;
+
+	/*
+	 * Create the data structure
+	 */
+	retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
+	if (retval)
+		return retval;
+
+	memset(rfs, 0, sizeof(struct ext2_resize_struct));
+	fs->priv_data = rfs;
+	rfs->old_fs = fs;
+	rfs->flags = flags;
+	rfs->itable_buf	 = 0;
+	rfs->progress = progress;
+
+	init_resource_track(&overall_track, "overall resize2fs", fs->io);
+	init_resource_track(&rtrack, "read_bitmaps", fs->io);
+	retval = ext2fs_read_bitmaps(fs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	fs->super->s_state |= EXT2_ERROR_FS;
+	ext2fs_mark_super_dirty(fs);
+	ext2fs_flush(fs);
+
+	init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
+	fix_uninit_block_bitmaps(fs);
+	print_resource_track(rfs, &rtrack, fs->io);
+	retval = ext2fs_dup_handle(fs, &rfs->new_fs);
+	if (retval)
+		goto errout;
+
+	init_resource_track(&rtrack, "resize_group_descriptors", fs->io);
+	retval = resize_group_descriptors(rfs, *new_size);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "move_bg_metadata", fs->io);
+	retval = move_bg_metadata(rfs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "zero_high_bits_in_metadata", fs->io);
+	retval = zero_high_bits_in_inodes(rfs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "adjust_superblock", fs->io);
+	retval = adjust_superblock(rfs, *new_size);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
+	fix_uninit_block_bitmaps(rfs->new_fs);
+	print_resource_track(rfs, &rtrack, fs->io);
+	/* Clear the block bitmap uninit flag for the last block group */
+	ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
+			     EXT2_BG_BLOCK_UNINIT);
+
+	*new_size = ext2fs_blocks_count(rfs->new_fs->super);
+
+	init_resource_track(&rtrack, "blocks_to_move", fs->io);
+	retval = blocks_to_move(rfs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+#ifdef RESIZE2FS_DEBUG
+	if (rfs->flags & RESIZE_DEBUG_BMOVE)
+		printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
+		       (unsigned long long) ext2fs_free_blocks_count(rfs->old_fs->super),
+		       (unsigned long long) ext2fs_free_blocks_count(rfs->new_fs->super),
+		       (unsigned long long) rfs->needed_blocks);
+#endif
+
+	init_resource_track(&rtrack, "block_mover", fs->io);
+	retval = block_mover(rfs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
+	retval = inode_scan_and_fix(rfs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "inode_ref_fix", fs->io);
+	retval = inode_ref_fix(rfs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "move_itables", fs->io);
+	retval = move_itables(rfs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	retval = clear_sparse_super2_last_group(rfs);
+	if (retval)
+		goto errout;
+
+	init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
+	retval = resize2fs_calculate_summary_stats(rfs->new_fs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "fix_resize_inode", fs->io);
+	retval = fix_resize_inode(rfs->new_fs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
+	retval = fix_sb_journal_backup(rfs->new_fs);
+	if (retval)
+		goto errout;
+	print_resource_track(rfs, &rtrack, fs->io);
+
+	retval = ext2fs_set_gdt_csum(rfs->new_fs);
+	if (retval)
+		goto errout;
+
+	rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
+	rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
+
+	print_resource_track(rfs, &overall_track, fs->io);
+	retval = ext2fs_close_free(&rfs->new_fs);
+	if (retval)
+		goto errout;
+
+	rfs->flags = flags;
+
+	ext2fs_free(rfs->old_fs);
+	rfs->old_fs = NULL;
+	if (rfs->itable_buf)
+		ext2fs_free_mem(&rfs->itable_buf);
+	if (rfs->reserve_blocks)
+		ext2fs_free_block_bitmap(rfs->reserve_blocks);
+	if (rfs->move_blocks)
+		ext2fs_free_block_bitmap(rfs->move_blocks);
+	ext2fs_free_mem(&rfs);
+
+	return 0;
+
+errout:
+	if (rfs->new_fs) {
+		ext2fs_free(rfs->new_fs);
+		rfs->new_fs = NULL;
+	}
+	if (rfs->itable_buf)
+		ext2fs_free_mem(&rfs->itable_buf);
+	ext2fs_free_mem(&rfs);
+	return retval;
+}
+
+/* Keep the size of the group descriptor region constant */
+static void adjust_reserved_gdt_blocks(ext2_filsys old_fs, ext2_filsys fs)
+{
+	if (ext2fs_has_feature_resize_inode(fs->super) &&
+	    (old_fs->desc_blocks != fs->desc_blocks)) {
+		int new;
+
+		new = ((int) fs->super->s_reserved_gdt_blocks) +
+			(old_fs->desc_blocks - fs->desc_blocks);
+		if (new < 0)
+			new = 0;
+		if (new > (int) fs->blocksize/4)
+			new = fs->blocksize/4;
+		fs->super->s_reserved_gdt_blocks = new;
+	}
+}
+
+/* Toggle 64bit mode */
+static errcode_t resize_group_descriptors(ext2_resize_t rfs, blk64_t new_size)
+{
+	void *o, *n, *new_group_desc;
+	dgrp_t i;
+	int copy_size;
+	errcode_t retval;
+
+	if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
+		return 0;
+
+	if (new_size != ext2fs_blocks_count(rfs->new_fs->super) ||
+	    ext2fs_blocks_count(rfs->new_fs->super) >= (1ULL << 32) ||
+	    (rfs->flags & RESIZE_DISABLE_64BIT &&
+	     rfs->flags & RESIZE_ENABLE_64BIT))
+		return EXT2_ET_INVALID_ARGUMENT;
+
+	if (rfs->flags & RESIZE_DISABLE_64BIT) {
+		ext2fs_clear_feature_64bit(rfs->new_fs->super);
+		rfs->new_fs->super->s_desc_size = EXT2_MIN_DESC_SIZE;
+	} else if (rfs->flags & RESIZE_ENABLE_64BIT) {
+		ext2fs_set_feature_64bit(rfs->new_fs->super);
+		rfs->new_fs->super->s_desc_size = EXT2_MIN_DESC_SIZE_64BIT;
+	}
+
+	if (EXT2_DESC_SIZE(rfs->old_fs->super) ==
+	    EXT2_DESC_SIZE(rfs->new_fs->super))
+		return 0;
+
+	o = rfs->new_fs->group_desc;
+	rfs->new_fs->desc_blocks = ext2fs_div_ceil(
+			rfs->old_fs->group_desc_count,
+			EXT2_DESC_PER_BLOCK(rfs->new_fs->super));
+	retval = ext2fs_get_arrayzero(rfs->new_fs->desc_blocks,
+				      rfs->old_fs->blocksize, &new_group_desc);
+	if (retval)
+		return retval;
+
+	n = new_group_desc;
+
+	if (EXT2_DESC_SIZE(rfs->old_fs->super) <=
+	    EXT2_DESC_SIZE(rfs->new_fs->super))
+		copy_size = EXT2_DESC_SIZE(rfs->old_fs->super);
+	else
+		copy_size = EXT2_DESC_SIZE(rfs->new_fs->super);
+	for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
+		memcpy(n, o, copy_size);
+		n = (char *)n + EXT2_DESC_SIZE(rfs->new_fs->super);
+		o = (char *)o + EXT2_DESC_SIZE(rfs->old_fs->super);
+	}
+
+	ext2fs_free_mem(&rfs->new_fs->group_desc);
+	rfs->new_fs->group_desc = new_group_desc;
+
+	for (i = 0; i < rfs->old_fs->group_desc_count; i++)
+		ext2fs_group_desc_csum_set(rfs->new_fs, i);
+
+	adjust_reserved_gdt_blocks(rfs->old_fs, rfs->new_fs);
+
+	return 0;
+}
+
+/* Move bitmaps/inode tables out of the way. */
+static errcode_t move_bg_metadata(ext2_resize_t rfs)
+{
+	dgrp_t i;
+	blk64_t b, c, d, old_desc_blocks, new_desc_blocks, j;
+	ext2fs_block_bitmap old_map, new_map;
+	int old, new;
+	errcode_t retval;
+	int cluster_ratio;
+
+	if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
+		return 0;
+
+	retval = ext2fs_allocate_block_bitmap(rfs->old_fs, "oldfs", &old_map);
+	if (retval)
+		return retval;
+
+	retval = ext2fs_allocate_block_bitmap(rfs->new_fs, "newfs", &new_map);
+	if (retval)
+		goto out;
+
+	if (ext2fs_has_feature_meta_bg(rfs->old_fs->super)) {
+		old_desc_blocks = rfs->old_fs->super->s_first_meta_bg;
+		new_desc_blocks = rfs->new_fs->super->s_first_meta_bg;
+	} else {
+		old_desc_blocks = rfs->old_fs->desc_blocks +
+				rfs->old_fs->super->s_reserved_gdt_blocks;
+		new_desc_blocks = rfs->new_fs->desc_blocks +
+				rfs->new_fs->super->s_reserved_gdt_blocks;
+	}
+
+	/* Construct bitmaps of super/descriptor blocks in old and new fs */
+	for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
+		retval = ext2fs_super_and_bgd_loc2(rfs->old_fs, i, &b, &c, &d,
+						   NULL);
+		if (retval)
+			goto out;
+		if (b)
+			ext2fs_mark_block_bitmap2(old_map, b);
+		for (j = 0; c != 0 && j < old_desc_blocks; j++)
+			ext2fs_mark_block_bitmap2(old_map, c + j);
+		if (d)
+			ext2fs_mark_block_bitmap2(old_map, d);
+
+		retval = ext2fs_super_and_bgd_loc2(rfs->new_fs, i, &b, &c, &d,
+						   NULL);
+		if (retval)
+			goto out;
+		if (b)
+			ext2fs_mark_block_bitmap2(new_map, b);
+		for (j = 0; c != 0 && j < new_desc_blocks; j++)
+			ext2fs_mark_block_bitmap2(new_map, c + j);
+		if (d)
+			ext2fs_mark_block_bitmap2(new_map, d);
+	}
+
+	cluster_ratio = EXT2FS_CLUSTER_RATIO(rfs->new_fs);
+
+	/* Find changes in block allocations for bg metadata */
+	for (b = EXT2FS_B2C(rfs->old_fs,
+			    rfs->old_fs->super->s_first_data_block);
+	     b < ext2fs_blocks_count(rfs->new_fs->super);
+	     b += cluster_ratio) {
+		old = ext2fs_test_block_bitmap2(old_map, b);
+		new = ext2fs_test_block_bitmap2(new_map, b);
+
+		if (old && !new) {
+			/* mark old_map, unmark new_map */
+			if (cluster_ratio == 1)
+				ext2fs_unmark_block_bitmap2(
+						rfs->new_fs->block_map, b);
+		} else if (!old && new)
+			; /* unmark old_map, mark new_map */
+		else {
+			ext2fs_unmark_block_bitmap2(old_map, b);
+			ext2fs_unmark_block_bitmap2(new_map, b);
+		}
+	}
+
+	/*
+	 * new_map now shows blocks that have been newly allocated.
+	 * old_map now shows blocks that have been newly freed.
+	 */
+
+	/*
+	 * Move any conflicting bitmaps and inode tables.  Ensure that we
+	 * don't try to free clusters associated with bitmaps or tables.
+	 */
+	for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
+		b = ext2fs_block_bitmap_loc(rfs->new_fs, i);
+		if (ext2fs_test_block_bitmap2(new_map, b))
+			ext2fs_block_bitmap_loc_set(rfs->new_fs, i, 0);
+		else if (ext2fs_test_block_bitmap2(old_map, b))
+			ext2fs_unmark_block_bitmap2(old_map, b);
+
+		b = ext2fs_inode_bitmap_loc(rfs->new_fs, i);
+		if (ext2fs_test_block_bitmap2(new_map, b))
+			ext2fs_inode_bitmap_loc_set(rfs->new_fs, i, 0);
+		else if (ext2fs_test_block_bitmap2(old_map, b))
+			ext2fs_unmark_block_bitmap2(old_map, b);
+
+		c = ext2fs_inode_table_loc(rfs->new_fs, i);
+		for (b = 0;
+		     b < rfs->new_fs->inode_blocks_per_group;
+		     b++) {
+			if (ext2fs_test_block_bitmap2(new_map, b + c))
+				ext2fs_inode_table_loc_set(rfs->new_fs, i, 0);
+			else if (ext2fs_test_block_bitmap2(old_map, b + c))
+				ext2fs_unmark_block_bitmap2(old_map, b + c);
+		}
+	}
+
+	/* Free unused clusters */
+	for (b = 0;
+	     cluster_ratio > 1 && b < ext2fs_blocks_count(rfs->new_fs->super);
+	     b += cluster_ratio)
+		if (ext2fs_test_block_bitmap2(old_map, b))
+			ext2fs_unmark_block_bitmap2(rfs->new_fs->block_map, b);
+out:
+	if (old_map)
+		ext2fs_free_block_bitmap(old_map);
+	if (new_map)
+		ext2fs_free_block_bitmap(new_map);
+	return retval;
+}
+
+/* Zero out the high bits of extent fields */
+static errcode_t zero_high_bits_in_extents(ext2_filsys fs, ext2_ino_t ino,
+				 struct ext2_inode *inode)
+{
+	ext2_extent_handle_t	handle;
+	struct ext2fs_extent	extent;
+	int			op = EXT2_EXTENT_ROOT;
+	errcode_t		errcode;
+
+	if (!(inode->i_flags & EXT4_EXTENTS_FL))
+		return 0;
+
+	errcode = ext2fs_extent_open(fs, ino, &handle);
+	if (errcode)
+		return errcode;
+
+	while (1) {
+		errcode = ext2fs_extent_get(handle, op, &extent);
+		if (errcode)
+			break;
+
+		op = EXT2_EXTENT_NEXT_SIB;
+
+		if (extent.e_pblk > (1ULL << 32)) {
+			extent.e_pblk &= (1ULL << 32) - 1;
+			errcode = ext2fs_extent_replace(handle, 0, &extent);
+			if (errcode)
+				break;
+		}
+	}
+
+	/* Ok if we run off the end */
+	if (errcode == EXT2_ET_EXTENT_NO_NEXT)
+		errcode = 0;
+	ext2fs_extent_free(handle);
+	return errcode;
+}
+
+/* Zero out the high bits of inodes. */
+static errcode_t zero_high_bits_in_inodes(ext2_resize_t rfs)
+{
+	ext2_filsys	fs = rfs->old_fs;
+	int length = EXT2_INODE_SIZE(fs->super);
+	struct ext2_inode *inode = NULL;
+	ext2_inode_scan	scan = NULL;
+	errcode_t	retval;
+	ext2_ino_t	ino;
+
+	if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
+		return 0;
+
+	if (fs->super->s_creator_os == EXT2_OS_HURD)
+		return 0;
+
+	retval = ext2fs_open_inode_scan(fs, 0, &scan);
+	if (retval)
+		return retval;
+
+	retval = ext2fs_get_mem(length, &inode);
+	if (retval)
+		goto out;
+
+	do {
+		retval = ext2fs_get_next_inode_full(scan, &ino, inode, length);
+		if (retval)
+			goto out;
+		if (!ino)
+			break;
+		if (!ext2fs_test_inode_bitmap2(fs->inode_map, ino))
+			continue;
+
+		/*
+		 * Here's how we deal with high block number fields:
+		 *
+		 *  - i_size_high has been been written out with i_size_lo
+		 *    since the ext2 days, so no conversion is needed.
+		 *
+		 *  - i_blocks_hi is guarded by both the huge_file feature and
+		 *    inode flags and has always been written out with
+		 *    i_blocks_lo if the feature is set.  The field is only
+		 *    ever read if both feature and inode flag are set, so
+		 *    we don't need to zero it now.
+		 *
+		 *  - i_file_acl_high can be uninitialized, so zero it if
+		 *    it isn't already.
+		 */
+		if (inode->osd2.linux2.l_i_file_acl_high) {
+			inode->osd2.linux2.l_i_file_acl_high = 0;
+			retval = ext2fs_write_inode_full(fs, ino, inode,
+							 length);
+			if (retval)
+				goto out;
+		}
+
+		retval = zero_high_bits_in_extents(fs, ino, inode);
+		if (retval)
+			goto out;
+	} while (ino);
+
+out:
+	if (inode)
+		ext2fs_free_mem(&inode);
+	if (scan)
+		ext2fs_close_inode_scan(scan);
+	return retval;
+}
+
+/*
+ * Clean up the bitmaps for uninitialized bitmaps
+ */
+static void fix_uninit_block_bitmaps(ext2_filsys fs)
+{
+	blk64_t		blk, lblk;
+	dgrp_t		g;
+	unsigned int	i;
+
+	if (!ext2fs_has_group_desc_csum(fs))
+		return;
+
+	for (g=0; g < fs->group_desc_count; g++) {
+		if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
+			continue;
+
+		blk = ext2fs_group_first_block2(fs, g);
+		lblk = ext2fs_group_last_block2(fs, g);
+		ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
+						  lblk - blk + 1);
+
+		ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
+		ext2fs_mark_block_bitmap2(fs->block_map,
+					  ext2fs_block_bitmap_loc(fs, g));
+		ext2fs_mark_block_bitmap2(fs->block_map,
+					  ext2fs_inode_bitmap_loc(fs, g));
+		for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
+		     i < fs->inode_blocks_per_group;
+		     i++, blk++)
+			ext2fs_mark_block_bitmap2(fs->block_map, blk);
+	}
+}
+
+/* --------------------------------------------------------------------
+ *
+ * Resize processing, phase 1.
+ *
+ * In this phase we adjust the in-memory superblock information, and
+ * initialize any new parts of the inode table.  The new parts of the
+ * inode table are created in virgin disk space, so we can abort here
+ * without any side effects.
+ * --------------------------------------------------------------------
+ */
+
+/*
+ * If the group descriptor's bitmap and inode table blocks are valid,
+ * release them in the new filesystem data structure, and mark them as
+ * reserved so the old inode table blocks don't get overwritten.
+ */
+static errcode_t free_gdp_blocks(ext2_filsys fs,
+				 ext2fs_block_bitmap reserve_blocks,
+				 ext2_filsys old_fs,
+				 dgrp_t group)
+{
+	blk64_t		blk;
+	unsigned int	j;
+	dgrp_t		i;
+	ext2fs_block_bitmap bg_map = NULL;
+	errcode_t	retval = 0;
+	dgrp_t		count = old_fs->group_desc_count - fs->group_desc_count;
+
+	/* If bigalloc, don't free metadata living in the same cluster */
+	if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
+		retval = ext2fs_allocate_block_bitmap(fs, "bgdata", &bg_map);
+		if (retval)
+			goto out;
+
+		retval = mark_table_blocks(fs, bg_map);
+		if (retval)
+			goto out;
+	}
+
+	for (i = group; i < group + count; i++) {
+		blk = ext2fs_block_bitmap_loc(old_fs, i);
+		if (blk &&
+		    (blk < ext2fs_blocks_count(fs->super)) &&
+		    !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
+			ext2fs_block_alloc_stats2(fs, blk, -1);
+			ext2fs_mark_block_bitmap2(reserve_blocks, blk);
+		}
+
+		blk = ext2fs_inode_bitmap_loc(old_fs, i);
+		if (blk &&
+		    (blk < ext2fs_blocks_count(fs->super)) &&
+		    !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
+			ext2fs_block_alloc_stats2(fs, blk, -1);
+			ext2fs_mark_block_bitmap2(reserve_blocks, blk);
+		}
+
+		blk = ext2fs_inode_table_loc(old_fs, i);
+		for (j = 0;
+		     j < fs->inode_blocks_per_group; j++, blk++) {
+			if (blk >= ext2fs_blocks_count(fs->super) ||
+			    (bg_map && ext2fs_test_block_bitmap2(bg_map, blk)))
+				continue;
+			ext2fs_block_alloc_stats2(fs, blk, -1);
+			ext2fs_mark_block_bitmap2(reserve_blocks, blk);
+		}
+	}
+
+out:
+	if (bg_map)
+		ext2fs_free_block_bitmap(bg_map);
+	return retval;
+}
+
+/*
+ * This routine is shared by the online and offline resize routines.
+ * All of the information which is adjusted in memory is done here.
+ */
+errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
+			 ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
+{
+	errcode_t	retval;
+	blk64_t		overhead = 0;
+	blk64_t		rem;
+	blk64_t		blk, group_block;
+	blk64_t		real_end;
+	blk64_t		old_numblocks, numblocks, adjblocks;
+	unsigned long	i, j, old_desc_blocks;
+	unsigned int	meta_bg, meta_bg_size;
+	int		has_super, csum_flag, has_bg;
+	unsigned long long new_inodes;	/* u64 to check for overflow */
+	double		percent;
+
+	ext2fs_blocks_count_set(fs->super, new_size);
+	fs->super->s_overhead_clusters = 0;
+
+retry:
+	fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
+				       fs->super->s_first_data_block,
+				       EXT2_BLOCKS_PER_GROUP(fs->super));
+	if (fs->group_desc_count == 0)
+		return EXT2_ET_TOOSMALL;
+	fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
+					  EXT2_DESC_PER_BLOCK(fs->super));
+
+	/*
+	 * Overhead is the number of bookkeeping blocks per group.  It
+	 * includes the superblock backup, the group descriptor
+	 * backups, the inode bitmap, the block bitmap, and the inode
+	 * table.
+	 */
+	overhead = (int) (2 + fs->inode_blocks_per_group);
+
+	has_bg = 0;
+	if (ext2fs_has_feature_sparse_super2(fs->super)) {
+		/*
+		 * We have to do this manually since
+		 * super->s_backup_bgs hasn't been set up yet.
+		 */
+		if (fs->group_desc_count == 2)
+			has_bg = fs->super->s_backup_bgs[0] != 0;
+		else
+			has_bg = fs->super->s_backup_bgs[1] != 0;
+	} else
+		has_bg = ext2fs_bg_has_super(fs, fs->group_desc_count - 1);
+	if (has_bg)
+		overhead += 1 + fs->desc_blocks +
+			fs->super->s_reserved_gdt_blocks;
+
+	/*
+	 * See if the last group is big enough to support the
+	 * necessary data structures.  If not, we need to get rid of
+	 * it.
+	 */
+	rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
+		fs->super->s_blocks_per_group;
+	if ((fs->group_desc_count == 1) && rem && (rem < overhead))
+		return EXT2_ET_TOOSMALL;
+	if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
+		ext2fs_blocks_count_set(fs->super,
+					ext2fs_blocks_count(fs->super) - rem);
+		goto retry;
+	}
+	/*
+	 * Adjust the number of inodes
+	 */
+	new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
+	if (new_inodes > ~0U) {
+		new_inodes = (unsigned long long) fs->super->s_inodes_per_group * (fs->group_desc_count - 1);
+		if (new_inodes <= ~0U) {
+			unsigned long long new_blocks =
+		((unsigned long long) fs->super->s_blocks_per_group *
+		 (fs->group_desc_count - 1)) + fs->super->s_first_data_block;
+
+			ext2fs_blocks_count_set(fs->super, new_blocks);
+			goto retry;
+		}
+		fprintf(stderr, _("inodes (%llu) must be less than %u\n"),
+			(unsigned long long) new_inodes, ~0U);
+		return EXT2_ET_TOO_MANY_INODES;
+	}
+	fs->super->s_inodes_count = fs->super->s_inodes_per_group *
+		fs->group_desc_count;
+
+	/*
+	 * Adjust the number of free blocks
+	 */
+	blk = ext2fs_blocks_count(old_fs->super);
+	if (blk > ext2fs_blocks_count(fs->super))
+		ext2fs_free_blocks_count_set(fs->super, 
+			ext2fs_free_blocks_count(fs->super) -
+			(blk - ext2fs_blocks_count(fs->super)));
+	else
+		ext2fs_free_blocks_count_set(fs->super, 
+			ext2fs_free_blocks_count(fs->super) +
+			(ext2fs_blocks_count(fs->super) - blk));
+
+	/*
+	 * Adjust the number of reserved blocks
+	 */
+	percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
+		ext2fs_blocks_count(old_fs->super);
+	ext2fs_r_blocks_count_set(fs->super,
+				  (percent * ext2fs_blocks_count(fs->super) /
+				   100.0));
+
+	/*
+	 * Adjust the bitmaps for size
+	 */
+	retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
+					    fs->super->s_inodes_count,
+					    fs->inode_map);
+	if (retval) goto errout;
+
+	real_end = EXT2_GROUPS_TO_BLOCKS(fs->super, fs->group_desc_count) - 1 +
+		fs->super->s_first_data_block;
+	retval = ext2fs_resize_block_bitmap2(new_size - 1,
+					     real_end, fs->block_map);
+	if (retval) goto errout;
+
+	/*
+	 * If we are growing the file system, also grow the size of
+	 * the reserve_blocks bitmap
+	 */
+	if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
+		retval = ext2fs_resize_block_bitmap2(new_size - 1,
+						     real_end, reserve_blocks);
+		if (retval) goto errout;
+	}
+
+	/*
+	 * Reallocate the group descriptors as necessary.
+	 */
+	if (EXT2_DESC_SIZE(old_fs->super) == EXT2_DESC_SIZE(fs->super) &&
+	    old_fs->desc_blocks != fs->desc_blocks) {
+		retval = ext2fs_resize_mem(old_fs->desc_blocks *
+					   fs->blocksize,
+					   fs->desc_blocks * fs->blocksize,
+					   &fs->group_desc);
+		if (retval)
+			goto errout;
+		if (fs->desc_blocks > old_fs->desc_blocks)
+			memset((char *) fs->group_desc +
+			       (old_fs->desc_blocks * fs->blocksize), 0,
+			       (fs->desc_blocks - old_fs->desc_blocks) *
+			       fs->blocksize);
+	}
+
+	/*
+	 * If the resize_inode feature is set, and we are changing the
+	 * number of descriptor blocks, then adjust
+	 * s_reserved_gdt_blocks if possible to avoid needing to move
+	 * the inode table either now or in the future.
+	 *
+	 * Note: If we're converting to 64bit mode, we did this earlier.
+	 */
+	if (EXT2_DESC_SIZE(old_fs->super) == EXT2_DESC_SIZE(fs->super))
+		adjust_reserved_gdt_blocks(old_fs, fs);
+
+	if (ext2fs_has_feature_meta_bg(fs->super) &&
+	    (fs->super->s_first_meta_bg > fs->desc_blocks)) {
+		ext2fs_clear_feature_meta_bg(fs->super);
+		fs->super->s_first_meta_bg = 0;
+	}
+
+	/*
+	 * Update the location of the backup superblocks if the
+	 * sparse_super2 feature is enabled.
+	 */
+	if (ext2fs_has_feature_sparse_super2(fs->super)) {
+		dgrp_t last_bg = fs->group_desc_count - 1;
+		dgrp_t old_last_bg = old_fs->group_desc_count - 1;
+
+		if (last_bg > old_last_bg) {
+			if (old_fs->group_desc_count == 1)
+				fs->super->s_backup_bgs[0] = 1;
+			if ((old_fs->group_desc_count < 3 &&
+			     fs->group_desc_count > 2) ||
+			    fs->super->s_backup_bgs[1])
+				fs->super->s_backup_bgs[1] = last_bg;
+		} else if (last_bg < old_last_bg) {
+			if (fs->super->s_backup_bgs[0] > last_bg)
+				fs->super->s_backup_bgs[0] = 0;
+			if (fs->super->s_backup_bgs[1] > last_bg)
+				fs->super->s_backup_bgs[1] = 0;
+			if (last_bg > 1 &&
+			    old_fs->super->s_backup_bgs[1] == old_last_bg)
+				fs->super->s_backup_bgs[1] = last_bg;
+		}
+	}
+
+	/*
+	 * If we are shrinking the number of block groups, we're done
+	 * and can exit now.
+	 */
+	if (old_fs->group_desc_count > fs->group_desc_count) {
+		/*
+		 * Check the block groups that we are chopping off
+		 * and free any blocks associated with their metadata
+		 */
+		retval = free_gdp_blocks(fs, reserve_blocks, old_fs,
+					 fs->group_desc_count);
+		goto errout;
+	}
+
+	/*
+	 * Fix the count of the last (old) block group
+	 */
+	old_numblocks = (ext2fs_blocks_count(old_fs->super) -
+			 old_fs->super->s_first_data_block) %
+				 old_fs->super->s_blocks_per_group;
+	if (!old_numblocks)
+		old_numblocks = old_fs->super->s_blocks_per_group;
+	if (old_fs->group_desc_count == fs->group_desc_count) {
+		numblocks = (ext2fs_blocks_count(fs->super) -
+			     fs->super->s_first_data_block) %
+			fs->super->s_blocks_per_group;
+		if (!numblocks)
+			numblocks = fs->super->s_blocks_per_group;
+	} else
+		numblocks = fs->super->s_blocks_per_group;
+	i = old_fs->group_desc_count - 1;
+	ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
+	ext2fs_group_desc_csum_set(fs, i);
+
+	/*
+	 * If the number of block groups is staying the same, we're
+	 * done and can exit now.  (If the number block groups is
+	 * shrinking, we had exited earlier.)
+	 */
+	if (old_fs->group_desc_count >= fs->group_desc_count) {
+		retval = 0;
+		goto errout;
+	}
+
+	/*
+	 * Initialize the new block group descriptors
+	 */
+	group_block = ext2fs_group_first_block2(fs,
+						old_fs->group_desc_count);
+	csum_flag = ext2fs_has_group_desc_csum(fs);
+	if (getenv("RESIZE2FS_FORCE_LAZY_ITABLE_INIT") ||
+	    (!getenv("RESIZE2FS_FORCE_ITABLE_INIT") &&
+	     access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0))
+		lazy_itable_init = 1;
+	if (ext2fs_has_feature_meta_bg(fs->super))
+		old_desc_blocks = fs->super->s_first_meta_bg;
+	else
+		old_desc_blocks = fs->desc_blocks +
+			fs->super->s_reserved_gdt_blocks;
+
+	/*
+	 * If we changed the number of block_group descriptor blocks,
+	 * we need to make sure they are all marked as reserved in the
+	 * filesystem's block allocation map.
+	 */
+	for (i = 0; i < old_fs->group_desc_count; i++)
+		ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
+
+	for (i = old_fs->group_desc_count;
+	     i < fs->group_desc_count; i++) {
+		memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
+		       sizeof(struct ext2_group_desc));
+		adjblocks = 0;
+
+		ext2fs_bg_flags_zap(fs, i);
+		if (csum_flag) {
+			ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
+			if (!lazy_itable_init)
+				ext2fs_bg_flags_set(fs, i,
+						    EXT2_BG_INODE_ZEROED);
+			ext2fs_bg_itable_unused_set(fs, i,
+					fs->super->s_inodes_per_group);
+		}
+
+		numblocks = ext2fs_group_blocks_count(fs, i);
+		if ((i < fs->group_desc_count - 1) && csum_flag)
+			ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
+
+		has_super = ext2fs_bg_has_super(fs, i);
+		if (has_super) {
+			ext2fs_block_alloc_stats2(fs, group_block, +1);
+			adjblocks++;
+		}
+		meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
+		meta_bg = i / meta_bg_size;
+		if (!ext2fs_has_feature_meta_bg(fs->super) ||
+		    (meta_bg < fs->super->s_first_meta_bg)) {
+			if (has_super) {
+				for (j=0; j < old_desc_blocks; j++)
+					ext2fs_block_alloc_stats2(fs,
+						 group_block + 1 + j, +1);
+				adjblocks += old_desc_blocks;
+			}
+		} else {
+			if (has_super)
+				has_super = 1;
+			if (((i % meta_bg_size) == 0) ||
+			    ((i % meta_bg_size) == 1) ||
+			    ((i % meta_bg_size) == (meta_bg_size-1)))
+				ext2fs_block_alloc_stats2(fs,
+						 group_block + has_super, +1);
+		}
+
+		adjblocks += 2 + fs->inode_blocks_per_group;
+
+		numblocks -= adjblocks;
+		ext2fs_free_blocks_count_set(fs->super,
+			     ext2fs_free_blocks_count(fs->super) - adjblocks);
+		fs->super->s_free_inodes_count +=
+			fs->super->s_inodes_per_group;
+		ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
+		ext2fs_bg_free_inodes_count_set(fs, i,
+						fs->super->s_inodes_per_group);
+		ext2fs_bg_used_dirs_count_set(fs, i, 0);
+		ext2fs_group_desc_csum_set(fs, i);
+
+		retval = ext2fs_allocate_group_table(fs, i, 0);
+		if (retval) goto errout;
+
+		group_block += fs->super->s_blocks_per_group;
+	}
+	retval = 0;
+
+	/*
+	 * Mark all of the metadata blocks as reserved so they won't
+	 * get allocated by the call to ext2fs_allocate_group_table()
+	 * in blocks_to_move(), where we allocate new blocks to
+	 * replace those allocation bitmap and inode table blocks
+	 * which have to get relocated to make space for an increased
+	 * number of the block group descriptors.
+	 */
+	if (reserve_blocks)
+		mark_table_blocks(fs, reserve_blocks);
+
+errout:
+	return (retval);
+}
+
+/*
+ * Replicate the first part of adjust_fs_info to determine what the
+ * new size of the file system should be.  This allows resize2fs to
+ * exit early if we aren't going to make any changes to the file
+ * system.
+ */
+void adjust_new_size(ext2_filsys fs, blk64_t *sizep)
+{
+	blk64_t		size, rem, overhead = 0;
+	unsigned long	desc_blocks;
+	dgrp_t		group_desc_count;
+	int		has_bg;
+	unsigned long long new_inodes;	/* u64 to check for overflow */
+
+	size = *sizep;
+retry:
+	group_desc_count = ext2fs_div64_ceil(size -
+					     fs->super->s_first_data_block,
+					     EXT2_BLOCKS_PER_GROUP(fs->super));
+	if (group_desc_count == 0)
+		return;
+	desc_blocks = ext2fs_div_ceil(group_desc_count,
+				      EXT2_DESC_PER_BLOCK(fs->super));
+
+	/*
+	 * Overhead is the number of bookkeeping blocks per group.  It
+	 * includes the superblock backup, the group descriptor
+	 * backups, the inode bitmap, the block bitmap, and the inode
+	 * table.
+	 */
+	overhead = (int) (2 + fs->inode_blocks_per_group);
+
+	has_bg = 0;
+	if (ext2fs_has_feature_sparse_super2(fs->super)) {
+		/*
+		 * We have to do this manually since
+		 * super->s_backup_bgs hasn't been set up yet.
+		 */
+		if (group_desc_count == 2)
+			has_bg = fs->super->s_backup_bgs[0] != 0;
+		else
+			has_bg = fs->super->s_backup_bgs[1] != 0;
+	} else
+		has_bg = ext2fs_bg_has_super(fs, group_desc_count - 1);
+	if (has_bg)
+		overhead += 1 + desc_blocks +
+			fs->super->s_reserved_gdt_blocks;
+
+	/*
+	 * See if the last group is big enough to support the
+	 * necessary data structures.  If not, we need to get rid of
+	 * it.
+	 */
+	rem = (size - fs->super->s_first_data_block) %
+		fs->super->s_blocks_per_group;
+	if ((group_desc_count == 1) && rem && (rem < overhead))
+		return;
+	if ((group_desc_count > 1) && rem && (rem < overhead+50)) {
+		size -= rem;
+		goto retry;
+	}
+
+	/*
+	 * If we need to reduce the size by no more than a block
+	 * group to avoid overrunning the max inode limit, do it.
+	 */
+	new_inodes =(unsigned long long) fs->super->s_inodes_per_group * group_desc_count;
+	if (new_inodes > ~0U) {
+		new_inodes = (unsigned long long) fs->super->s_inodes_per_group * (group_desc_count - 1);
+		if (new_inodes > ~0U)
+			return;
+		size = ((unsigned long long) fs->super->s_blocks_per_group *
+			(group_desc_count - 1)) + fs->super->s_first_data_block;
+
+		goto retry;
+	}
+	*sizep = size;
+}
+
+/*
+ * This routine adjusts the superblock and other data structures, both
+ * in disk as well as in memory...
+ */
+static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
+{
+	ext2_filsys	fs = rfs->new_fs;
+	int		adj = 0;
+	errcode_t	retval;
+	unsigned long	i;
+	unsigned long	max_group;
+
+	ext2fs_mark_super_dirty(fs);
+	ext2fs_mark_bb_dirty(fs);
+	ext2fs_mark_ib_dirty(fs);
+
+	retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
+					      &rfs->reserve_blocks);
+	if (retval)
+		return retval;
+
+	retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
+	if (retval)
+		goto errout;
+
+	/*
+	 * Check to make sure there are enough inodes
+	 */
+	if ((rfs->old_fs->super->s_inodes_count -
+	     rfs->old_fs->super->s_free_inodes_count) >
+	    rfs->new_fs->super->s_inodes_count) {
+		retval = ENOSPC;
+		goto errout;
+	}
+
+	/*
+	 * If we are shrinking the number block groups, we're done and
+	 * can exit now.
+	 */
+	if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
+		retval = 0;
+		goto errout;
+	}
+
+	/*
+	 * If the number of block groups is staying the same, we're
+	 * done and can exit now.  (If the number block groups is
+	 * shrinking, we had exited earlier.)
+	 */
+	if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
+		retval = 0;
+		goto errout;
+	}
+
+	/*
+	 * If we are using uninit_bg (aka GDT_CSUM) and the kernel
+	 * supports lazy inode initialization, we can skip
+	 * initializing the inode table.
+	 */
+	if (lazy_itable_init && ext2fs_has_group_desc_csum(fs)) {
+		retval = 0;
+		goto errout;
+	}
+
+	/*
+	 * Initialize the inode table
+	 */
+	retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
+				&rfs->itable_buf);
+	if (retval)
+		goto errout;
+
+	memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
+	adj = rfs->old_fs->group_desc_count;
+	max_group = fs->group_desc_count - adj;
+	if (rfs->progress) {
+		retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
+				       0, max_group);
+		if (retval)
+			goto errout;
+	}
+	for (i = rfs->old_fs->group_desc_count;
+	     i < fs->group_desc_count; i++) {
+		/*
+		 * Write out the new inode table
+		 */
+		retval = ext2fs_zero_blocks2(fs, ext2fs_inode_table_loc(fs, i),
+					     fs->inode_blocks_per_group, NULL,
+					     NULL);
+		if (retval)
+			goto errout;
+
+		io_channel_flush(fs->io);
+		if (rfs->progress) {
+			retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
+					       i - adj + 1, max_group);
+			if (retval)
+				goto errout;
+		}
+	}
+	io_channel_flush(fs->io);
+	retval = 0;
+
+errout:
+	return retval;
+}
+
+/* --------------------------------------------------------------------
+ *
+ * Resize processing, phase 2.
+ *
+ * In this phase we adjust determine which blocks need to be moved, in
+ * blocks_to_move().  We then copy the blocks to their ultimate new
+ * destinations using block_mover().  Since we are copying blocks to
+ * their new locations, again during this pass we can abort without
+ * any problems.
+ * --------------------------------------------------------------------
+ */
+
+/*
+ * This helper function creates a block bitmap with all of the
+ * filesystem meta-data blocks.
+ */
+static errcode_t mark_table_blocks(ext2_filsys fs,
+				   ext2fs_block_bitmap bmap)
+{
+	dgrp_t			i;
+	blk64_t			blk;
+
+	for (i = 0; i < fs->group_desc_count; i++) {
+		ext2fs_reserve_super_and_bgd(fs, i, bmap);
+
+		/*
+		 * Mark the blocks used for the inode table
+		 */
+		blk = ext2fs_inode_table_loc(fs, i);
+		if (blk)
+			ext2fs_mark_block_bitmap_range2(bmap, blk,
+						fs->inode_blocks_per_group);
+
+		/*
+		 * Mark block used for the block bitmap
+		 */
+		blk = ext2fs_block_bitmap_loc(fs, i);
+		if (blk)
+			ext2fs_mark_block_bitmap2(bmap, blk);
+
+		/*
+		 * Mark block used for the inode bitmap
+		 */
+		blk = ext2fs_inode_bitmap_loc(fs, i);
+		if (blk)
+			ext2fs_mark_block_bitmap2(bmap, blk);
+	}
+	/* Reserve the MMP block */
+	if (ext2fs_has_feature_mmp(fs->super) &&
+	    fs->super->s_mmp_block > fs->super->s_first_data_block &&
+	    fs->super->s_mmp_block < ext2fs_blocks_count(fs->super))
+		ext2fs_mark_block_bitmap2(bmap, fs->super->s_mmp_block);
+	return 0;
+}
+
+/*
+ * This function checks to see if a particular block (either a
+ * superblock or a block group descriptor) overlaps with an inode or
+ * block bitmap block, or with the inode table.
+ */
+static void mark_fs_metablock(ext2_resize_t rfs,
+			      ext2fs_block_bitmap meta_bmap,
+			      int group, blk64_t blk)
+{
+	ext2_filsys fs = rfs->new_fs;
+
+	ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
+	ext2fs_block_alloc_stats2(fs, blk, +1);
+
+	/*
+	 * Check to see if we overlap with the inode or block bitmap,
+	 * or the inode tables.  If not, and the block is in use, then
+	 * mark it as a block to be moved.
+	 */
+	if (is_block_bm(fs, group, blk)) {
+		ext2fs_block_bitmap_loc_set(fs, group, 0);
+		rfs->needed_blocks++;
+		return;
+	}
+	if (is_inode_bm(fs, group, blk)) {
+		ext2fs_inode_bitmap_loc_set(fs, group, 0);
+		rfs->needed_blocks++;
+		return;
+	}
+	if (is_inode_tb(fs, group, blk)) {
+		ext2fs_inode_table_loc_set(fs, group, 0);
+		rfs->needed_blocks++;
+		return;
+	}
+	if (ext2fs_has_feature_flex_bg(fs->super)) {
+		dgrp_t i;
+
+		for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
+			if (is_block_bm(fs, i, blk)) {
+				ext2fs_block_bitmap_loc_set(fs, i, 0);
+				rfs->needed_blocks++;
+				return;
+			}
+			if (is_inode_bm(fs, i, blk)) {
+				ext2fs_inode_bitmap_loc_set(fs, i, 0);
+				rfs->needed_blocks++;
+				return;
+			}
+			if (is_inode_tb(fs, i, blk)) {
+				ext2fs_inode_table_loc_set(fs, i, 0);
+				rfs->needed_blocks++;
+				return;
+			}
+		}
+	}
+
+	if (ext2fs_has_group_desc_csum(fs) &&
+	    (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
+		/*
+		 * If the block bitmap is uninitialized, which means
+		 * nothing other than standard metadata in use.
+		 */
+		return;
+	} else if (blk < ext2fs_blocks_count(rfs->old_fs->super) &&
+		   ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
+		   !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
+		ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
+		rfs->needed_blocks++;
+	}
+}
+
+
+/*
+ * This routine marks and unmarks reserved blocks in the new block
+ * bitmap.  It also determines which blocks need to be moved and
+ * places this information into the move_blocks bitmap.
+ */
+static errcode_t blocks_to_move(ext2_resize_t rfs)
+{
+	unsigned int	j;
+	int		has_super;
+	dgrp_t		i, max_groups, g;
+	blk64_t		blk, group_blk;
+	blk64_t		old_blocks, new_blocks, group_end, cluster_freed;
+	blk64_t		new_size;
+	unsigned int	meta_bg, meta_bg_size;
+	errcode_t	retval;
+	ext2_filsys 	fs, old_fs;
+	ext2fs_block_bitmap	meta_bmap, new_meta_bmap = NULL;
+	int		flex_bg;
+
+	fs = rfs->new_fs;
+	old_fs = rfs->old_fs;
+	if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
+		fs = rfs->old_fs;
+
+	retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
+					      &rfs->move_blocks);
+	if (retval)
+		return retval;
+
+	retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
+					      &meta_bmap);
+	if (retval)
+		return retval;
+
+	retval = mark_table_blocks(old_fs, meta_bmap);
+	if (retval)
+		return retval;
+
+	fs = rfs->new_fs;
+
+	/*
+	 * If we're shrinking the filesystem, we need to move any
+	 * group's metadata blocks (either allocation bitmaps or the
+	 * inode table) which are beyond the end of the new
+	 * filesystem.
+	 */
+	new_size = ext2fs_blocks_count(fs->super);
+	if (new_size < ext2fs_blocks_count(old_fs->super)) {
+		for (g = 0; g < fs->group_desc_count; g++) {
+			int realloc = 0;
+			/*
+			 * ext2fs_allocate_group_table will re-allocate any
+			 * metadata blocks whose location is set to zero.
+			 */
+			if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
+				ext2fs_block_bitmap_loc_set(fs, g, 0);
+				realloc = 1;
+			}
+			if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
+				ext2fs_inode_bitmap_loc_set(fs, g, 0);
+				realloc = 1;
+			}
+			if ((ext2fs_inode_table_loc(fs, g) +
+			     fs->inode_blocks_per_group) > new_size) {
+				ext2fs_inode_table_loc_set(fs, g, 0);
+				realloc = 1;
+			}
+
+			if (realloc) {
+				retval = ext2fs_allocate_group_table(fs, g, 0);
+				if (retval)
+					return retval;
+			}
+		}
+	}
+
+	/*
+	 * If we're shrinking the filesystem, we need to move all of
+	 * the blocks that don't fit any more
+	 */
+	for (blk = ext2fs_blocks_count(fs->super);
+	     blk < ext2fs_blocks_count(old_fs->super); blk++) {
+		g = ext2fs_group_of_blk2(fs, blk);
+		if (ext2fs_has_group_desc_csum(fs) &&
+		    ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
+			/*
+			 * The block bitmap is uninitialized, so skip
+			 * to the next block group.
+			 */
+			blk = ext2fs_group_first_block2(fs, g+1) - 1;
+			continue;
+		}
+		if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
+		    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
+			ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
+			rfs->needed_blocks++;
+		}
+		ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
+	}
+
+	if (ext2fs_has_feature_meta_bg(old_fs->super))
+		old_blocks = old_fs->super->s_first_meta_bg;
+	else
+		old_blocks = old_fs->desc_blocks +
+			old_fs->super->s_reserved_gdt_blocks;
+	if (ext2fs_has_feature_meta_bg(fs->super))
+		new_blocks = fs->super->s_first_meta_bg;
+	else
+		new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
+
+	retval = reserve_sparse_super2_last_group(rfs, meta_bmap);
+	if (retval)
+		goto errout;
+
+	if (EXT2_DESC_SIZE(rfs->old_fs->super) ==
+	    EXT2_DESC_SIZE(rfs->new_fs->super) &&
+	    old_blocks == new_blocks) {
+		retval = 0;
+		goto errout;
+	}
+
+	max_groups = fs->group_desc_count;
+	if (max_groups > old_fs->group_desc_count)
+		max_groups = old_fs->group_desc_count;
+	group_blk = old_fs->super->s_first_data_block;
+	/*
+	 * If we're reducing the number of descriptor blocks, this
+	 * makes life easy.  :-)   We just have to mark some extra
+	 * blocks as free.
+	 */
+	if (old_blocks > new_blocks) {
+		if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
+			retval = ext2fs_allocate_block_bitmap(fs,
+							_("new meta blocks"),
+							&new_meta_bmap);
+			if (retval)
+				goto errout;
+
+			retval = mark_table_blocks(fs, new_meta_bmap);
+			if (retval)
+				goto errout;
+		}
+
+		for (i = 0; i < max_groups; i++) {
+			if (!ext2fs_bg_has_super(old_fs, i)) {
+				group_blk += fs->super->s_blocks_per_group;
+				continue;
+			}
+			group_end = group_blk + 1 + old_blocks;
+			for (blk = group_blk + 1 + new_blocks;
+			     blk < group_end;) {
+				if (new_meta_bmap == NULL ||
+				    !ext2fs_test_block_bitmap2(new_meta_bmap,
+							       blk)) {
+					cluster_freed =
+						EXT2FS_CLUSTER_RATIO(fs) -
+						(blk &
+						 EXT2FS_CLUSTER_MASK(fs));
+					if (cluster_freed > group_end - blk)
+						cluster_freed = group_end - blk;
+					ext2fs_block_alloc_stats2(fs, blk, -1);
+					blk += EXT2FS_CLUSTER_RATIO(fs);
+					rfs->needed_blocks -= cluster_freed;
+					continue;
+				}
+				rfs->needed_blocks--;
+				blk++;
+			}
+			group_blk += fs->super->s_blocks_per_group;
+		}
+		retval = 0;
+		goto errout;
+	}
+	/*
+	 * If we're increasing the number of descriptor blocks, life
+	 * gets interesting....
+	 */
+	meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
+	flex_bg = ext2fs_has_feature_flex_bg(fs->super);
+	/* first reserve all of the existing fs meta blocks */
+	for (i = 0; i < max_groups; i++) {
+		has_super = ext2fs_bg_has_super(fs, i);
+		if (has_super)
+			mark_fs_metablock(rfs, meta_bmap, i, group_blk);
+
+		meta_bg = i / meta_bg_size;
+		if (!ext2fs_has_feature_meta_bg(fs->super) ||
+		    (meta_bg < fs->super->s_first_meta_bg)) {
+			if (has_super) {
+				for (blk = group_blk+1;
+				     blk < group_blk + 1 + new_blocks; blk++)
+					mark_fs_metablock(rfs, meta_bmap,
+							  i, blk);
+			}
+		} else {
+			if (has_super)
+				has_super = 1;
+			if (((i % meta_bg_size) == 0) ||
+			    ((i % meta_bg_size) == 1) ||
+			    ((i % meta_bg_size) == (meta_bg_size-1)))
+				mark_fs_metablock(rfs, meta_bmap, i,
+						  group_blk + has_super);
+		}
+
+		/*
+		 * Reserve the existing meta blocks that we know
+		 * aren't to be moved.
+		 *
+		 * For flex_bg file systems, in order to avoid
+		 * overwriting fs metadata (especially inode table
+		 * blocks) belonging to a different block group when
+		 * we are relocating the inode tables, we need to
+		 * reserve all existing fs metadata blocks.
+		 */
+		if (ext2fs_block_bitmap_loc(fs, i))
+			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
+				 ext2fs_block_bitmap_loc(fs, i));
+		else if (flex_bg && i < old_fs->group_desc_count)
+			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
+				 ext2fs_block_bitmap_loc(old_fs, i));
+
+		if (ext2fs_inode_bitmap_loc(fs, i))
+			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
+				 ext2fs_inode_bitmap_loc(fs, i));
+		else if (flex_bg && i < old_fs->group_desc_count)
+			ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
+				 ext2fs_inode_bitmap_loc(old_fs, i));
+
+		if (ext2fs_inode_table_loc(fs, i))
+			ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
+					ext2fs_inode_table_loc(fs, i),
+					fs->inode_blocks_per_group);
+		else if (flex_bg && i < old_fs->group_desc_count)
+			ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
+					ext2fs_inode_table_loc(old_fs, i),
+					old_fs->inode_blocks_per_group);
+
+		group_blk += rfs->new_fs->super->s_blocks_per_group;
+	}
+
+	/* Allocate the missing data structures */
+	for (i = 0; i < max_groups; i++) {
+		if (ext2fs_inode_table_loc(fs, i) &&
+		    ext2fs_inode_bitmap_loc(fs, i) &&
+		    ext2fs_block_bitmap_loc(fs, i))
+			continue;
+
+		retval = ext2fs_allocate_group_table(fs, i,
+						     rfs->reserve_blocks);
+		if (retval)
+			goto errout;
+
+		/*
+		 * For those structures that have changed, we need to
+		 * do bookkeeping.
+		 */
+		if (ext2fs_block_bitmap_loc(old_fs, i) !=
+		    (blk = ext2fs_block_bitmap_loc(fs, i))) {
+			ext2fs_block_alloc_stats2(fs, blk, +1);
+			if (blk < ext2fs_blocks_count(old_fs->super) &&
+			    ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
+			    !ext2fs_test_block_bitmap2(meta_bmap, blk))
+				ext2fs_mark_block_bitmap2(rfs->move_blocks,
+							 blk);
+		}
+		if (ext2fs_inode_bitmap_loc(old_fs, i) !=
+		    (blk = ext2fs_inode_bitmap_loc(fs, i))) {
+			ext2fs_block_alloc_stats2(fs, blk, +1);
+			if (blk < ext2fs_blocks_count(old_fs->super) &&
+			    ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
+			    !ext2fs_test_block_bitmap2(meta_bmap, blk))
+				ext2fs_mark_block_bitmap2(rfs->move_blocks,
+							 blk);
+		}
+
+		/*
+		 * The inode table, if we need to relocate it, is
+		 * handled specially.  We have to reserve the blocks
+		 * for both the old and the new inode table, since we
+		 * can't have the inode table be destroyed during the
+		 * block relocation phase.
+		 */
+		if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
+			continue;	/* inode table not moved */
+
+		rfs->needed_blocks += fs->inode_blocks_per_group;
+
+		/*
+		 * Mark the new inode table as in use in the new block
+		 * allocation bitmap, and move any blocks that might
+		 * be necessary.
+		 */
+		for (blk = ext2fs_inode_table_loc(fs, i), j=0;
+		     j < fs->inode_blocks_per_group ; j++, blk++) {
+			ext2fs_block_alloc_stats2(fs, blk, +1);
+			if (blk < ext2fs_blocks_count(old_fs->super) &&
+			    ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
+			    !ext2fs_test_block_bitmap2(meta_bmap, blk))
+				ext2fs_mark_block_bitmap2(rfs->move_blocks,
+							 blk);
+		}
+
+		/*
+		 * Make sure the old inode table is reserved in the
+		 * block reservation bitmap.
+		 */
+		for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
+		     j < fs->inode_blocks_per_group ; j++, blk++)
+			ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
+	}
+	retval = 0;
+
+errout:
+	if (new_meta_bmap)
+		ext2fs_free_block_bitmap(new_meta_bmap);
+	if (meta_bmap)
+		ext2fs_free_block_bitmap(meta_bmap);
+
+	return retval;
+}
+
+/*
+ * This helper function tries to allocate a new block.  We try to
+ * avoid hitting the original group descriptor blocks at least at
+ * first, since we want to make it possible to recover from a badly
+ * aborted resize operation as much as possible.
+ *
+ * In the future, I may further modify this routine to balance out
+ * where we get the new blocks across the various block groups.
+ * Ideally we would allocate blocks that corresponded with the block
+ * group of the containing inode, and keep contiguous blocks
+ * together.  However, this very difficult to do efficiently, since we
+ * don't have the necessary information up front.
+ */
+
+#define AVOID_OLD	1
+#define DESPERATION	2
+
+static void init_block_alloc(ext2_resize_t rfs)
+{
+	rfs->alloc_state = AVOID_OLD;
+	rfs->new_blk = rfs->new_fs->super->s_first_data_block;
+#if 0
+	/* HACK for testing */
+	if (ext2fs_blocks_count(rfs->new_fs->super) >
+	    ext2fs_blocks_count(rfs->old_fs->super))
+		rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
+#endif
+}
+
+static blk64_t get_new_block(ext2_resize_t rfs)
+{
+	ext2_filsys	fs = rfs->new_fs;
+
+	while (1) {
+		if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
+			if (rfs->alloc_state == DESPERATION)
+				return 0;
+
+#ifdef RESIZE2FS_DEBUG
+			if (rfs->flags & RESIZE_DEBUG_BMOVE)
+				printf("Going into desperation mode "
+				       "for block allocations\n");
+#endif
+			rfs->alloc_state = DESPERATION;
+			rfs->new_blk = fs->super->s_first_data_block;
+			continue;
+		}
+		if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
+		    ext2fs_test_block_bitmap2(rfs->reserve_blocks,
+					     rfs->new_blk) ||
+		    ((rfs->alloc_state == AVOID_OLD) &&
+		     (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
+		     ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
+					      rfs->new_blk))) {
+			rfs->new_blk++;
+			continue;
+		}
+		return rfs->new_blk;
+	}
+}
+
+static errcode_t resize2fs_get_alloc_block(ext2_filsys fs,
+					   blk64_t goal EXT2FS_ATTR((unused)),
+					   blk64_t *ret)
+{
+	ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
+	blk64_t blk;
+	int group;
+
+	blk = get_new_block(rfs);
+	if (!blk)
+		return ENOSPC;
+
+#ifdef RESIZE2FS_DEBUG
+	if (rfs->flags & 0xF)
+		printf("get_alloc_block allocating %llu\n",
+		       (unsigned long long) blk);
+#endif
+
+	ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
+	ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
+
+	group = ext2fs_group_of_blk2(rfs->old_fs, blk);
+	ext2fs_clear_block_uninit(rfs->old_fs, group);
+	group = ext2fs_group_of_blk2(rfs->new_fs, blk);
+	ext2fs_clear_block_uninit(rfs->new_fs, group);
+
+	*ret = (blk64_t) blk;
+	return 0;
+}
+
+static errcode_t block_mover(ext2_resize_t rfs)
+{
+	blk64_t			blk, old_blk, new_blk;
+	ext2_filsys		fs = rfs->new_fs;
+	ext2_filsys		old_fs = rfs->old_fs;
+	errcode_t		retval;
+	__u64			c, size;
+	int			to_move, moved;
+	ext2_badblocks_list	badblock_list = 0;
+	int			bb_modified = 0;
+
+	fs->get_alloc_block = resize2fs_get_alloc_block;
+	old_fs->get_alloc_block = resize2fs_get_alloc_block;
+
+	retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
+	if (retval)
+		return retval;
+
+	new_blk = fs->super->s_first_data_block;
+	if (!rfs->itable_buf) {
+		retval = ext2fs_get_array(fs->blocksize,
+					fs->inode_blocks_per_group,
+					&rfs->itable_buf);
+		if (retval)
+			goto errout;
+	}
+	retval = ext2fs_create_extent_table(&rfs->bmap, 0);
+	if (retval)
+		goto errout;
+
+	/*
+	 * The first step is to figure out where all of the blocks
+	 * will go.
+	 */
+	to_move = moved = 0;
+	init_block_alloc(rfs);
+	for (blk = B2C(old_fs->super->s_first_data_block);
+	     blk < ext2fs_blocks_count(old_fs->super);
+	     blk += EXT2FS_CLUSTER_RATIO(fs)) {
+		if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
+			continue;
+		if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
+			continue;
+		if (ext2fs_badblocks_list_test(badblock_list, blk)) {
+			ext2fs_badblocks_list_del(badblock_list, blk);
+			bb_modified++;
+			continue;
+		}
+
+		new_blk = get_new_block(rfs);
+		if (!new_blk) {
+			retval = ENOSPC;
+			goto errout;
+		}
+		ext2fs_block_alloc_stats2(fs, new_blk, +1);
+		ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
+		to_move++;
+	}
+
+	if (to_move == 0) {
+		if (rfs->bmap) {
+			ext2fs_free_extent_table(rfs->bmap);
+			rfs->bmap = 0;
+		}
+		retval = 0;
+		goto errout;
+	}
+
+	/*
+	 * Step two is to actually move the blocks
+	 */
+	retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
+	if (retval) goto errout;
+
+	if (rfs->progress) {
+		retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
+					 0, to_move);
+		if (retval)
+			goto errout;
+	}
+	while (1) {
+		retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
+		if (retval) goto errout;
+		if (!size)
+			break;
+		old_blk = C2B(old_blk);
+		new_blk = C2B(new_blk);
+		size = C2B(size);
+#ifdef RESIZE2FS_DEBUG
+		if (rfs->flags & RESIZE_DEBUG_BMOVE)
+			printf("Moving %llu blocks %llu->%llu\n",
+			       (unsigned long long) size,
+			       (unsigned long long) old_blk,
+			       (unsigned long long) new_blk);
+#endif
+		do {
+			c = size;
+			if (c > fs->inode_blocks_per_group)
+				c = fs->inode_blocks_per_group;
+			retval = io_channel_read_blk64(fs->io, old_blk, c,
+						       rfs->itable_buf);
+			if (retval) goto errout;
+			retval = io_channel_write_blk64(fs->io, new_blk, c,
+							rfs->itable_buf);
+			if (retval) goto errout;
+			size -= c;
+			new_blk += c;
+			old_blk += c;
+			moved += c;
+			if (rfs->progress) {
+				io_channel_flush(fs->io);
+				retval = (rfs->progress)(rfs,
+						E2_RSZ_BLOCK_RELOC_PASS,
+						moved, to_move);
+				if (retval)
+					goto errout;
+			}
+		} while (size > 0);
+		io_channel_flush(fs->io);
+	}
+
+errout:
+	if (badblock_list) {
+		if (!retval && bb_modified)
+			retval = ext2fs_update_bb_inode(old_fs,
+							badblock_list);
+		ext2fs_badblocks_list_free(badblock_list);
+	}
+	return retval;
+}
+
+
+/* --------------------------------------------------------------------
+ *
+ * Resize processing, phase 3
+ *
+ * --------------------------------------------------------------------
+ */
+
+
+/*
+ * The extent translation table is stored in clusters so we need to
+ * take special care when mapping a source block number to its
+ * destination block number.
+ */
+static __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
+{
+	__u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
+
+	if (new_block != 0)
+		new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
+	return new_block;
+}
+
+struct process_block_struct {
+	ext2_resize_t 		rfs;
+	ext2_ino_t		ino;
+	ext2_ino_t		old_ino;
+	struct ext2_inode *	inode;
+	errcode_t		error;
+	int			is_dir;
+	int			changed;
+	int			has_extents;
+};
+
+static int process_block(ext2_filsys fs, blk64_t	*block_nr,
+			 e2_blkcnt_t blockcnt,
+			 blk64_t ref_block EXT2FS_ATTR((unused)),
+			 int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
+{
+	struct process_block_struct *pb;
+	errcode_t	retval;
+	blk64_t		block, new_block;
+	int		ret = 0;
+
+	pb = (struct process_block_struct *) priv_data;
+	block = *block_nr;
+	if (pb->rfs->bmap) {
+		new_block = extent_translate(fs, pb->rfs->bmap, block);
+		if (new_block) {
+			*block_nr = new_block;
+			ret |= BLOCK_CHANGED;
+			pb->changed = 1;
+#ifdef RESIZE2FS_DEBUG
+			if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
+				printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
+				       pb->old_ino, (long long) blockcnt,
+				       (unsigned long long) block,
+				       (unsigned long long) new_block);
+#endif
+			block = new_block;
+		}
+	}
+
+	if (pb->is_dir) {
+		retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
+					       block, (int) blockcnt);
+		if (retval) {
+			pb->error = retval;
+			ret |= BLOCK_ABORT;
+		}
+	}
+	return ret;
+}
+
+/*
+ * Progress callback
+ */
+static errcode_t progress_callback(ext2_filsys fs,
+				   ext2_inode_scan scan EXT2FS_ATTR((unused)),
+				   dgrp_t group, void * priv_data)
+{
+	ext2_resize_t rfs = (ext2_resize_t) priv_data;
+	errcode_t		retval;
+
+	/*
+	 * This check is to protect against old ext2 libraries.  It
+	 * shouldn't be needed against new libraries.
+	 */
+	if ((group+1) == 0)
+		return 0;
+
+	if (rfs->progress) {
+		io_channel_flush(fs->io);
+		retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
+					 group+1, fs->group_desc_count);
+		if (retval)
+			return retval;
+	}
+
+	return 0;
+}
+
+static errcode_t migrate_ea_block(ext2_resize_t rfs, ext2_ino_t ino,
+				  struct ext2_inode *inode, int *changed)
+{
+	char *buf = NULL;
+	blk64_t new_block;
+	errcode_t err = 0;
+
+	/* No EA block or no remapping?  Quit early. */
+	if (ext2fs_file_acl_block(rfs->old_fs, inode) == 0 || !rfs->bmap)
+		return 0;
+	new_block = extent_translate(rfs->old_fs, rfs->bmap,
+		ext2fs_file_acl_block(rfs->old_fs, inode));
+	if (new_block == 0)
+		return 0;
+
+	/* Set the new ACL block */
+	ext2fs_file_acl_block_set(rfs->old_fs, inode, new_block);
+
+	/* Update checksum */
+	if (ext2fs_has_feature_metadata_csum(rfs->new_fs->super)) {
+		err = ext2fs_get_mem(rfs->old_fs->blocksize, &buf);
+		if (err)
+			return err;
+		rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
+		err = ext2fs_read_ext_attr3(rfs->old_fs, new_block, buf, ino);
+		rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
+		if (err)
+			goto out;
+		err = ext2fs_write_ext_attr3(rfs->old_fs, new_block, buf, ino);
+		if (err)
+			goto out;
+	}
+	*changed = 1;
+
+out:
+	ext2fs_free_mem(&buf);
+	return err;
+}
+
+static void quiet_com_err_proc(const char *whoami EXT2FS_ATTR((unused)),
+			       errcode_t code EXT2FS_ATTR((unused)),
+			       const char *fmt EXT2FS_ATTR((unused)),
+			       va_list args EXT2FS_ATTR((unused)))
+{
+}
+
+static int fix_ea_entries(ext2_extent imap, struct ext2_ext_attr_entry *entry,
+			  struct ext2_ext_attr_entry *end, ext2_ino_t last_ino)
+{
+	int modified = 0;
+	ext2_ino_t new_ino;
+
+	while (entry < end && !EXT2_EXT_IS_LAST_ENTRY(entry)) {
+		if (entry->e_value_inum > last_ino) {
+			new_ino = ext2fs_extent_translate(imap,
+							  entry->e_value_inum);
+			entry->e_value_inum = new_ino;
+			modified = 1;
+		}
+		entry = EXT2_EXT_ATTR_NEXT(entry);
+	}
+	return modified;
+}
+
+static int fix_ea_ibody_entries(ext2_extent imap,
+				struct ext2_inode_large *inode, int inode_size,
+				ext2_ino_t last_ino)
+{
+	struct ext2_ext_attr_entry *start, *end;
+	__u32 *ea_magic;
+
+	if (inode->i_extra_isize == 0)
+		return 0;
+
+	ea_magic = (__u32 *)((char *)inode + EXT2_GOOD_OLD_INODE_SIZE +
+				inode->i_extra_isize);
+	if (*ea_magic != EXT2_EXT_ATTR_MAGIC)
+		return 0;
+
+	start = (struct ext2_ext_attr_entry *)(ea_magic + 1);
+	end = (struct ext2_ext_attr_entry *)((char *)inode + inode_size);
+
+	return fix_ea_entries(imap, start, end, last_ino);
+}
+
+static int fix_ea_block_entries(ext2_extent imap, char *block_buf,
+				unsigned int blocksize, ext2_ino_t last_ino)
+{
+	struct ext2_ext_attr_header *header;
+	struct ext2_ext_attr_entry *start, *end;
+
+	header = (struct ext2_ext_attr_header *)block_buf;
+	start = (struct ext2_ext_attr_entry *)(header+1);
+	end = (struct ext2_ext_attr_entry *)(block_buf + blocksize);
+
+	return fix_ea_entries(imap, start, end, last_ino);
+}
+
+/* A simple LRU cache to check recently processed blocks. */
+struct blk_cache {
+	int cursor;
+	blk64_t blks[4];
+};
+
+#define BLK_IN_CACHE(b,c) ((b) == (c).blks[0] || (b) == (c).blks[1] || \
+			   (b) == (c).blks[2] || (b) == (c).blks[3])
+#define BLK_ADD_CACHE(b,c) { 			\
+	(c).blks[(c).cursor] = (b);		\
+	(c).cursor = ((c).cursor + 1) % 4;	\
+}
+
+static errcode_t fix_ea_inode_refs(ext2_resize_t rfs, struct ext2_inode *inode,
+				   char *block_buf, ext2_ino_t last_ino)
+{
+	ext2_filsys	fs = rfs->new_fs;
+	ext2_inode_scan	scan = NULL;
+	ext2_ino_t	ino;
+	int		inode_size = EXT2_INODE_SIZE(fs->super);
+	blk64_t		blk;
+	int		modified;
+	struct blk_cache blk_cache;
+	struct ext2_ext_attr_header *header;
+	errcode_t		retval;
+
+	memset(&blk_cache, 0, sizeof(blk_cache));
+
+	header = (struct ext2_ext_attr_header *)block_buf;
+
+	retval = ext2fs_open_inode_scan(fs, 0, &scan);
+	if (retval)
+		goto out;
+
+	while (1) {
+		retval = ext2fs_get_next_inode_full(scan, &ino, inode,
+						    inode_size);
+		if (retval)
+			goto out;
+		if (!ino)
+			break;
+
+		if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
+			continue; /* inode not in use */
+
+		if (inode_size != EXT2_GOOD_OLD_INODE_SIZE) {
+			modified = fix_ea_ibody_entries(rfs->imap,
+					(struct ext2_inode_large *)inode,
+					inode_size, last_ino);
+			if (modified) {
+				retval = ext2fs_write_inode_full(fs, ino, inode,
+								 inode_size);
+				if (retval)
+					goto out;
+			}
+		}
+
+		blk = ext2fs_file_acl_block(fs, inode);
+		if (blk && !BLK_IN_CACHE(blk, blk_cache)) {
+			retval = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
+			if (retval)
+				goto out;
+
+			modified = fix_ea_block_entries(rfs->imap, block_buf,
+							fs->blocksize,
+							last_ino);
+			if (modified) {
+				retval = ext2fs_write_ext_attr3(fs, blk,
+								block_buf, ino);
+				if (retval)
+					goto out;
+				/*
+				 * If refcount is greater than 1, we might see
+				 * the same block referenced by other inodes
+				 * later.
+				 */
+				if (header->h_refcount > 1)
+					BLK_ADD_CACHE(blk, blk_cache);
+			}
+		}
+	}
+	retval = 0;
+out:
+	if (scan)
+		ext2fs_close_inode_scan(scan);
+	return retval;
+
+}
+static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
+{
+	struct process_block_struct	pb;
+	ext2_ino_t		ino, new_inode;
+	struct ext2_inode 	*inode = NULL;
+	ext2_inode_scan 	scan = NULL;
+	errcode_t		retval;
+	char			*block_buf = 0;
+	ext2_ino_t		start_to_move;
+	int			inode_size;
+	int			update_ea_inode_refs = 0;
+
+	if ((rfs->old_fs->group_desc_count <=
+	     rfs->new_fs->group_desc_count) &&
+	    !rfs->bmap)
+		return 0;
+
+	set_com_err_hook(quiet_com_err_proc);
+
+	retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
+	if (retval) goto errout;
+
+	retval = ext2fs_init_dblist(rfs->old_fs, 0);
+	if (retval) goto errout;
+	retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
+	if (retval) goto errout;
+
+	start_to_move = (rfs->new_fs->group_desc_count *
+			 rfs->new_fs->super->s_inodes_per_group);
+
+	if (rfs->progress) {
+		retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
+					 0, rfs->old_fs->group_desc_count);
+		if (retval)
+			goto errout;
+	}
+	ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
+	pb.rfs = rfs;
+	pb.inode = inode;
+	pb.error = 0;
+	new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
+	inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
+	inode = malloc(inode_size);
+	if (!inode) {
+		retval = ENOMEM;
+		goto errout;
+	}
+	/*
+	 * First, copy all of the inodes that need to be moved
+	 * elsewhere in the inode table
+	 */
+	while (1) {
+		retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
+		if (retval) goto errout;
+		if (!ino)
+			break;
+
+		if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
+			continue; /* inode not in use */
+
+		pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
+		pb.changed = 0;
+
+		/* Remap EA block */
+		retval = migrate_ea_block(rfs, ino, inode, &pb.changed);
+		if (retval)
+			goto errout;
+
+		new_inode = ino;
+		if (ino <= start_to_move)
+			goto remap_blocks; /* Don't need to move inode. */
+
+		/*
+		 * Find a new inode.  Now that extents and directory blocks
+		 * are tied to the inode number through the checksum, we must
+		 * set up the new inode before we start rewriting blocks.
+		 */
+		retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
+		if (retval)
+			goto errout;
+
+		ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
+					  pb.is_dir);
+		/*
+		 * i_ctime field in xattr inodes contain a portion of the ref
+		 * count, do not overwrite.
+		 */
+		if (inode->i_flags & EXT4_EA_INODE_FL)
+			update_ea_inode_refs = 1;
+		else
+			inode->i_ctime = rfs->old_fs->now ?
+				rfs->old_fs->now : time(0);
+
+		retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
+						inode, inode_size);
+		if (retval)
+			goto errout;
+		pb.changed = 0;
+
+#ifdef RESIZE2FS_DEBUG
+		if (rfs->flags & RESIZE_DEBUG_INODEMAP)
+			printf("Inode moved %u->%u\n", ino, new_inode);
+#endif
+		if (!rfs->imap) {
+			retval = ext2fs_create_extent_table(&rfs->imap, 0);
+			if (retval)
+				goto errout;
+		}
+		ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
+
+remap_blocks:
+		if (pb.changed)
+			retval = ext2fs_write_inode_full(rfs->old_fs,
+							 new_inode,
+							 inode, inode_size);
+		if (retval)
+			goto errout;
+
+		/*
+		 * Update inodes to point to new blocks; schedule directory
+		 * blocks for inode remapping.  Need to write out dir blocks
+		 * with new inode numbers if we have metadata_csum enabled.
+		 */
+		rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
+		if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
+		    (rfs->bmap || pb.is_dir)) {
+			pb.ino = new_inode;
+			pb.old_ino = ino;
+			pb.has_extents = inode->i_flags & EXT4_EXTENTS_FL;
+			retval = ext2fs_block_iterate3(rfs->old_fs,
+						       new_inode, 0, block_buf,
+						       process_block, &pb);
+			if (retval)
+				goto errout;
+			if (pb.error) {
+				retval = pb.error;
+				goto errout;
+			}
+		} else if ((inode->i_flags & EXT4_INLINE_DATA_FL) &&
+			   (rfs->bmap || pb.is_dir)) {
+			/* inline data dir; update it too */
+			retval = ext2fs_add_dir_block2(rfs->old_fs->dblist,
+						       new_inode, 0, 0);
+			if (retval)
+				goto errout;
+		}
+
+		/* Fix up extent block checksums with the new inode number */
+		if (ext2fs_has_feature_metadata_csum(rfs->old_fs->super) &&
+		    (inode->i_flags & EXT4_EXTENTS_FL)) {
+			retval = ext2fs_fix_extents_checksums(rfs->old_fs,
+							      new_inode, NULL);
+			if (retval)
+				goto errout;
+		}
+	}
+
+	if (update_ea_inode_refs &&
+	    ext2fs_has_feature_ea_inode(rfs->new_fs->super)) {
+		retval = fix_ea_inode_refs(rfs, inode, block_buf,
+					   start_to_move);
+		if (retval)
+			goto errout;
+	}
+	io_channel_flush(rfs->old_fs->io);
+
+errout:
+	reset_com_err_hook();
+	rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
+	if (rfs->bmap) {
+		ext2fs_free_extent_table(rfs->bmap);
+		rfs->bmap = 0;
+	}
+	if (scan)
+		ext2fs_close_inode_scan(scan);
+	if (block_buf)
+		ext2fs_free_mem(&block_buf);
+	free(inode);
+	return retval;
+}
+
+/* --------------------------------------------------------------------
+ *
+ * Resize processing, phase 4.
+ *
+ * --------------------------------------------------------------------
+ */
+
+struct istruct {
+	ext2_resize_t rfs;
+	errcode_t	err;
+	unsigned int	max_dirs;
+	unsigned int	num;
+};
+
+static int check_and_change_inodes(ext2_ino_t dir,
+				   int entry EXT2FS_ATTR((unused)),
+				   struct ext2_dir_entry *dirent, int offset,
+				   int	blocksize EXT2FS_ATTR((unused)),
+				   char *buf EXT2FS_ATTR((unused)),
+				   void *priv_data)
+{
+	struct istruct *is = (struct istruct *) priv_data;
+	struct ext2_inode 	inode;
+	ext2_ino_t		new_inode;
+	errcode_t		retval;
+	int			ret = 0;
+
+	if (is->rfs->progress && offset == 0) {
+		io_channel_flush(is->rfs->old_fs->io);
+		is->err = (is->rfs->progress)(is->rfs,
+					      E2_RSZ_INODE_REF_UPD_PASS,
+					      ++is->num, is->max_dirs);
+		if (is->err)
+			return DIRENT_ABORT;
+	}
+
+	/*
+	 * If we have checksums enabled and the inode wasn't present in the
+	 * old fs, then we must rewrite all dir blocks with new checksums.
+	 */
+	if (ext2fs_has_feature_metadata_csum(is->rfs->old_fs->super) &&
+	    !ext2fs_test_inode_bitmap2(is->rfs->old_fs->inode_map, dir))
+		ret |= DIRENT_CHANGED;
+
+	if (!dirent->inode)
+		return ret;
+
+	new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
+
+	if (!new_inode)
+		return ret;
+#ifdef RESIZE2FS_DEBUG
+	if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
+		printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
+		       dir, ext2fs_dirent_name_len(dirent), dirent->name,
+		       dirent->inode, new_inode);
+#endif
+
+	dirent->inode = new_inode;
+
+	/* Update the directory mtime and ctime */
+	retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
+	if (retval == 0) {
+		inode.i_mtime = inode.i_ctime = is->rfs->old_fs->now ?
+			is->rfs->old_fs->now : time(0);
+		is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
+		if (is->err)
+			return ret | DIRENT_ABORT;
+	}
+
+	return ret | DIRENT_CHANGED;
+}
+
+static errcode_t inode_ref_fix(ext2_resize_t rfs)
+{
+	errcode_t		retval;
+	struct istruct 		is;
+
+	if (!rfs->imap)
+		return 0;
+
+	/*
+	 * Now, we iterate over all of the directories to update the
+	 * inode references
+	 */
+	is.num = 0;
+	is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
+	is.rfs = rfs;
+	is.err = 0;
+
+	if (rfs->progress) {
+		retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
+					 0, is.max_dirs);
+		if (retval)
+			goto errout;
+	}
+
+	rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
+	retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
+					   DIRENT_FLAG_INCLUDE_EMPTY, 0,
+					   check_and_change_inodes, &is);
+	rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
+	if (retval)
+		goto errout;
+	if (is.err) {
+		retval = is.err;
+		goto errout;
+	}
+
+	if (rfs->progress && (is.num < is.max_dirs))
+		(rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
+				is.max_dirs, is.max_dirs);
+
+errout:
+	ext2fs_free_extent_table(rfs->imap);
+	rfs->imap = 0;
+	return retval;
+}
+
+
+/* --------------------------------------------------------------------
+ *
+ * Resize processing, phase 5.
+ *
+ * In this phase we actually move the inode table around, and then
+ * update the summary statistics.  This is scary, since aborting here
+ * will potentially scramble the filesystem.  (We are moving the
+ * inode tables around in place, and so the potential for lost data,
+ * or at the very least scrambling the mapping between filenames and
+ * inode numbers is very high in case of a power failure here.)
+ * --------------------------------------------------------------------
+ */
+
+
+/*
+ * A very scary routine --- this one moves the inode table around!!!
+ *
+ * After this you have to use the rfs->new_fs file handle to read and
+ * write inodes.
+ */
+static errcode_t move_itables(ext2_resize_t rfs)
+{
+	int		n, num, size;
+	long long	diff;
+	dgrp_t		i, max_groups;
+	ext2_filsys	fs = rfs->new_fs;
+	char		*cp;
+	blk64_t		old_blk, new_blk, blk, cluster_freed;
+	errcode_t	retval;
+	int		to_move, moved;
+	unsigned int	j;
+	ext2fs_block_bitmap	new_bmap = NULL;
+
+	max_groups = fs->group_desc_count;
+	if (max_groups > rfs->old_fs->group_desc_count)
+		max_groups = rfs->old_fs->group_desc_count;
+
+	size = fs->blocksize * fs->inode_blocks_per_group;
+	if (!rfs->itable_buf) {
+		retval = ext2fs_get_mem(size, &rfs->itable_buf);
+		if (retval)
+			return retval;
+	}
+
+	if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
+		retval = ext2fs_allocate_block_bitmap(fs, _("new meta blocks"),
+						      &new_bmap);
+		if (retval)
+			return retval;
+
+		retval = mark_table_blocks(fs, new_bmap);
+		if (retval)
+			goto errout;
+	}
+
+	/*
+	 * Figure out how many inode tables we need to move
+	 */
+	to_move = moved = 0;
+	for (i=0; i < max_groups; i++)
+		if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
+		    ext2fs_inode_table_loc(fs, i))
+			to_move++;
+
+	if (to_move == 0) {
+		retval = 0;
+		goto errout;
+	}
+
+	if (rfs->progress) {
+		retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
+				       0, to_move);
+		if (retval)
+			goto errout;
+	}
+
+	rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
+
+	for (i=0; i < max_groups; i++) {
+		old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
+		new_blk = ext2fs_inode_table_loc(fs, i);
+		diff = new_blk - old_blk;
+
+#ifdef RESIZE2FS_DEBUG
+		if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
+			printf("Itable move group %d block %llu->%llu (diff %lld)\n",
+			       i, (unsigned long long) old_blk,
+			       (unsigned long long) new_blk, diff);
+#endif
+
+		if (!diff)
+			continue;
+		if (diff < 0)
+			diff = 0;
+
+		retval = io_channel_read_blk64(fs->io, old_blk,
+					       fs->inode_blocks_per_group,
+					       rfs->itable_buf);
+		if (retval)
+			goto errout;
+		/*
+		 * The end of the inode table segment often contains
+		 * all zeros, and we're often only moving the inode
+		 * table down a block or two.  If so, we can optimize
+		 * things by not rewriting blocks that we know to be zero
+		 * already.
+		 */
+		for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
+			if (*cp)
+				break;
+		n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
+#ifdef RESIZE2FS_DEBUG
+		if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
+			printf("%d blocks of zeros...\n", n);
+#endif
+		num = fs->inode_blocks_per_group;
+		if (n > diff)
+			num -= n;
+
+		retval = io_channel_write_blk64(fs->io, new_blk,
+						num, rfs->itable_buf);
+		if (retval) {
+			io_channel_write_blk64(fs->io, old_blk,
+					       num, rfs->itable_buf);
+			goto errout;
+		}
+		if (n > diff) {
+			retval = io_channel_write_blk64(fs->io,
+			      old_blk + fs->inode_blocks_per_group,
+			      diff, (rfs->itable_buf +
+				     (fs->inode_blocks_per_group - diff) *
+				     fs->blocksize));
+			if (retval)
+				goto errout;
+		}
+
+		for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
+		     j < fs->inode_blocks_per_group;) {
+			if (new_bmap == NULL ||
+			    !ext2fs_test_block_bitmap2(new_bmap, blk)) {
+				ext2fs_block_alloc_stats2(fs, blk, -1);
+				cluster_freed = EXT2FS_CLUSTER_RATIO(fs) -
+						(blk & EXT2FS_CLUSTER_MASK(fs));
+				blk += cluster_freed;
+				j += cluster_freed;
+				continue;
+			}
+			blk++;
+			j++;
+		}
+
+		ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
+		ext2fs_group_desc_csum_set(rfs->old_fs, i);
+		ext2fs_mark_super_dirty(rfs->old_fs);
+		ext2fs_flush(rfs->old_fs);
+
+		if (rfs->progress) {
+			retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
+					       ++moved, to_move);
+			if (retval)
+				goto errout;
+		}
+	}
+	mark_table_blocks(fs, fs->block_map);
+	ext2fs_flush(fs);
+#ifdef RESIZE2FS_DEBUG
+	if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
+		printf("Inode table move finished.\n");
+#endif
+	retval = 0;
+
+errout:
+	if (new_bmap)
+		ext2fs_free_block_bitmap(new_bmap);
+	return retval;
+}
+
+/*
+ * This function is used when expanding a file system.  It frees the
+ * superblock and block group descriptor blocks from the block group
+ * which is no longer the last block group.
+ */
+static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs)
+{
+	ext2_filsys	fs = rfs->new_fs;
+	ext2_filsys	old_fs = rfs->old_fs;
+	errcode_t	retval;
+	dgrp_t		old_last_bg = rfs->old_fs->group_desc_count - 1;
+	dgrp_t		last_bg = fs->group_desc_count - 1;
+	blk64_t		sb, old_desc;
+	blk_t		num;
+
+	if (!ext2fs_has_feature_sparse_super2(fs->super))
+		return 0;
+
+	if (last_bg <= old_last_bg)
+		return 0;
+
+	if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
+	    fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
+		return 0;
+
+	if (old_fs->super->s_backup_bgs[0] != old_last_bg &&
+	    old_fs->super->s_backup_bgs[1] != old_last_bg)
+		return 0;
+
+	if (fs->super->s_backup_bgs[0] == old_last_bg ||
+	    fs->super->s_backup_bgs[1] == old_last_bg)
+		return 0;
+
+	if (old_last_bg == 0)
+		return 0;
+
+	retval = ext2fs_super_and_bgd_loc2(rfs->old_fs, old_last_bg,
+					   &sb, &old_desc, NULL, &num);
+	if (retval)
+		return retval;
+
+	if (sb)
+		ext2fs_unmark_block_bitmap2(fs->block_map, sb);
+	if (old_desc)
+		ext2fs_unmark_block_bitmap_range2(fs->block_map, old_desc, num);
+	return 0;
+}
+
+/*
+ * This function is used when shrinking a file system.  We need to
+ * utilize blocks from what will be the new last block group for the
+ * backup superblock and block group descriptor blocks.
+ * Unfortunately, those blocks may be used by other files or fs
+ * metadata blocks.  We need to mark them as being in use.
+ */
+static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
+						 ext2fs_block_bitmap meta_bmap)
+{
+	ext2_filsys	fs = rfs->new_fs;
+	ext2_filsys	old_fs = rfs->old_fs;
+	errcode_t	retval;
+	dgrp_t		old_last_bg = rfs->old_fs->group_desc_count - 1;
+	dgrp_t		last_bg = fs->group_desc_count - 1;
+	dgrp_t		g;
+	blk64_t		blk, sb, old_desc;
+	blk_t		i, num;
+	int		realloc = 0;
+
+	if (!ext2fs_has_feature_sparse_super2(fs->super))
+		return 0;
+
+	if (last_bg >= old_last_bg)
+		return 0;
+
+	if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
+	    fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
+		return 0;
+
+	if (fs->super->s_backup_bgs[0] != last_bg &&
+	    fs->super->s_backup_bgs[1] != last_bg)
+		return 0;
+
+	if (old_fs->super->s_backup_bgs[0] == last_bg ||
+	    old_fs->super->s_backup_bgs[1] == last_bg)
+		return 0;
+
+	retval = ext2fs_super_and_bgd_loc2(rfs->new_fs, last_bg,
+					   &sb, &old_desc, NULL, &num);
+	if (retval)
+		return retval;
+
+	if (last_bg && !sb) {
+		fputs(_("Should never happen!  No sb in last super_sparse bg?\n"),
+		      stderr);
+		exit(1);
+	}
+	if (old_desc && old_desc != sb+1) {
+		fputs(_("Should never happen!  Unexpected old_desc in "
+			"super_sparse bg?\n"),
+		      stderr);
+		exit(1);
+	}
+	num = (old_desc) ? num : 1;
+
+	/* Reserve the backup blocks */
+	ext2fs_mark_block_bitmap_range2(fs->block_map, sb, num);
+
+	for (g = 0; g < fs->group_desc_count; g++) {
+		blk64_t mb;
+
+		mb = ext2fs_block_bitmap_loc(fs, g);
+		if ((mb >= sb) && (mb < sb + num)) {
+			ext2fs_block_bitmap_loc_set(fs, g, 0);
+			realloc = 1;
+		}
+		mb = ext2fs_inode_bitmap_loc(fs, g);
+		if ((mb >= sb) && (mb < sb + num)) {
+			ext2fs_inode_bitmap_loc_set(fs, g, 0);
+			realloc = 1;
+		}
+		mb = ext2fs_inode_table_loc(fs, g);
+		if ((mb < sb + num) &&
+		    (sb < mb + fs->inode_blocks_per_group)) {
+			ext2fs_inode_table_loc_set(fs, g, 0);
+			realloc = 1;
+		}
+		if (realloc) {
+			retval = ext2fs_allocate_group_table(fs, g, 0);
+			if (retval)
+				return retval;
+		}
+	}
+
+	for (blk = sb, i = 0; i < num; blk++, i++) {
+		if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
+		    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
+			ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
+			rfs->needed_blocks++;
+		}
+		ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
+	}
+	return 0;
+}
+
+/*
+ * Fix the resize inode
+ */
+static errcode_t fix_resize_inode(ext2_filsys fs)
+{
+	struct ext2_inode	inode;
+	errcode_t		retval;
+
+	if (!ext2fs_has_feature_resize_inode(fs->super))
+		return 0;
+
+	retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
+	if (retval) goto errout;
+
+	ext2fs_iblk_set(fs, &inode, 1);
+
+	retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
+	if (retval) goto errout;
+
+	if (!inode.i_block[EXT2_DIND_BLOCK]) {
+		/*
+		 * Avoid zeroing out block #0; that's rude.  This
+		 * should never happen anyway since the filesystem
+		 * should be fsck'ed and we assume it is consistent.
+		 */
+		fprintf(stderr, "%s",
+			_("Should never happen: resize inode corrupt!\n"));
+		exit(1);
+	}
+
+	retval = ext2fs_zero_blocks2(fs, inode.i_block[EXT2_DIND_BLOCK], 1,
+				     NULL, NULL);
+	if (retval)
+		goto errout;
+
+	retval = ext2fs_create_resize_inode(fs);
+	if (retval)
+		goto errout;
+
+errout:
+	return retval;
+}
+
+/*
+ * Finally, recalculate the summary information
+ */
+static errcode_t resize2fs_calculate_summary_stats(ext2_filsys fs)
+{
+	errcode_t	retval;
+	blk64_t		blk = fs->super->s_first_data_block;
+	ext2_ino_t	ino;
+	unsigned int	n, group, count;
+	blk64_t		total_clusters_free = 0;
+	int		total_inodes_free = 0;
+	int		group_free = 0;
+	int		uninit = 0;
+	char		*bitmap_buf;
+
+	/*
+	 * First calculate the block statistics
+	 */
+	bitmap_buf = malloc(fs->blocksize);
+	if (!bitmap_buf)
+		return ENOMEM;
+	for (group = 0; group < fs->group_desc_count;
+	     group++) {
+		retval = ext2fs_get_block_bitmap_range2(fs->block_map,
+			B2C(blk), fs->super->s_clusters_per_group, bitmap_buf);
+		if (retval) {
+			free(bitmap_buf);
+			return retval;
+		}
+		n = ext2fs_bitcount(bitmap_buf,
+				    fs->super->s_clusters_per_group / 8);
+		group_free = fs->super->s_clusters_per_group - n;
+		total_clusters_free += group_free;
+		ext2fs_bg_free_blocks_count_set(fs, group, group_free);
+		ext2fs_group_desc_csum_set(fs, group);
+		blk += fs->super->s_blocks_per_group;
+	}
+	free(bitmap_buf);
+	ext2fs_free_blocks_count_set(fs->super, C2B(total_clusters_free));
+
+	/*
+	 * Next, calculate the inode statistics
+	 */
+	group_free = 0;
+	count = 0;
+	group = 0;
+
+	/* Protect loop from wrap-around if s_inodes_count maxed */
+	uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
+	for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
+		if (uninit ||
+		    !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
+			group_free++;
+			total_inodes_free++;
+		}
+		count++;
+		if ((count == fs->super->s_inodes_per_group) ||
+		    (ino == fs->super->s_inodes_count)) {
+			ext2fs_bg_free_inodes_count_set(fs, group, group_free);
+			ext2fs_group_desc_csum_set(fs, group);
+			group++;
+			if (group >= fs->group_desc_count)
+				break;
+			count = 0;
+			group_free = 0;
+			uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
+		}
+	}
+	fs->super->s_free_inodes_count = total_inodes_free;
+	ext2fs_mark_super_dirty(fs);
+	return 0;
+}
+
+/*
+ *  Journal may have been relocated; update the backup journal blocks
+ *  in the superblock.
+ */
+static errcode_t fix_sb_journal_backup(ext2_filsys fs)
+{
+	errcode_t	  retval;
+	struct ext2_inode inode;
+
+	if (!ext2fs_has_feature_journal(fs->super))
+		return 0;
+
+	/* External journal? Nothing to do. */
+	if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
+		return 0;
+
+	retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
+	if (retval)
+		return retval;
+	memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
+	fs->super->s_jnl_blocks[15] = inode.i_size_high;
+	fs->super->s_jnl_blocks[16] = inode.i_size;
+	fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
+	ext2fs_mark_super_dirty(fs);
+	return 0;
+}
+
+static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
+			       int old_desc_blocks)
+{
+	blk64_t	super_blk, old_desc_blk, new_desc_blk;
+	int overhead;
+
+	/* inode table blocks plus allocation bitmaps */
+	overhead = fs->inode_blocks_per_group + 2;
+
+	ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
+				  &old_desc_blk, &new_desc_blk, 0);
+	if ((grp == 0) || super_blk)
+		overhead++;
+	if (old_desc_blk)
+		overhead += old_desc_blocks;
+	else if (new_desc_blk)
+		overhead++;
+	return overhead;
+}
+
+
+/*
+ * calculate the minimum number of blocks the given fs can be resized to
+ */
+blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
+{
+	ext2_ino_t inode_count;
+	dgrp_t groups, flex_groups;
+	blk64_t blks_needed, data_blocks;
+	blk64_t grp, data_needed, last_start;
+	blk64_t overhead = 0;
+	int old_desc_blocks;
+	unsigned flexbg_size = 1U << fs->super->s_log_groups_per_flex;
+
+	/*
+	 * first figure out how many group descriptors we need to
+	 * handle the number of inodes we have
+	 */
+	inode_count = fs->super->s_inodes_count -
+		fs->super->s_free_inodes_count;
+	blks_needed = ext2fs_div_ceil(inode_count,
+				      fs->super->s_inodes_per_group) *
+		(blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super);
+	groups = ext2fs_div64_ceil(blks_needed,
+				   EXT2_BLOCKS_PER_GROUP(fs->super));
+#ifdef RESIZE2FS_DEBUG
+	if (flags & RESIZE_DEBUG_MIN_CALC)
+		printf("fs has %d inodes, %d groups required.\n",
+		       inode_count, groups);
+#endif
+
+	/*
+	 * number of old-style block group descriptor blocks
+	 */
+	if (ext2fs_has_feature_meta_bg(fs->super))
+		old_desc_blocks = fs->super->s_first_meta_bg;
+	else
+		old_desc_blocks = fs->desc_blocks +
+			fs->super->s_reserved_gdt_blocks;
+
+	/* calculate how many blocks are needed for data */
+	data_needed = ext2fs_blocks_count(fs->super);
+	for (grp = 0; grp < fs->group_desc_count; grp++) {
+		__u32 n = ext2fs_bg_free_blocks_count(fs, grp);
+
+		if (n > EXT2_BLOCKS_PER_GROUP(fs->super))
+			n = EXT2_BLOCKS_PER_GROUP(fs->super);
+		n += calc_group_overhead(fs, grp, old_desc_blocks);
+		if (data_needed < n) {
+			if (flags & RESIZE_DEBUG_MIN_CALC)
+				printf("file system appears inconsistent?!?\n");
+			return ext2fs_blocks_count(fs->super);
+		}
+		data_needed -= n;
+	}
+#ifdef RESIZE2FS_DEBUG
+	if (flags & RESIZE_DEBUG_MIN_CALC)
+		printf("fs requires %llu data blocks.\n",
+		       (unsigned long long) data_needed);
+#endif
+
+	/*
+	 * For ext4 we need to allow for up to a flex_bg worth of
+	 * inode tables of slack space so the resize operation can be
+	 * guaranteed to finish.
+	 */
+	flex_groups = groups;
+	if (ext2fs_has_feature_flex_bg(fs->super)) {
+		dgrp_t remainder = groups & (flexbg_size - 1);
+
+		flex_groups += flexbg_size - remainder;
+		if (flex_groups > fs->group_desc_count)
+			flex_groups = fs->group_desc_count;
+	}
+
+	/*
+	 * figure out how many data blocks we have given the number of groups
+	 * we need for our inodes
+	 */
+	data_blocks = EXT2_GROUPS_TO_BLOCKS(fs->super, groups);
+	last_start = 0;
+	for (grp = 0; grp < flex_groups; grp++) {
+		overhead = calc_group_overhead(fs, grp, old_desc_blocks);
+
+		/*
+		 * we want to keep track of how much data we can store in
+		 * the groups leading up to the last group so we can determine
+		 * how big the last group needs to be
+		 */
+		if (grp < (groups - 1))
+			last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
+				overhead;
+
+		if (data_blocks > overhead)
+			data_blocks -= overhead;
+		else
+			data_blocks = 0;
+	}
+#ifdef RESIZE2FS_DEBUG
+	if (flags & RESIZE_DEBUG_MIN_CALC)
+		printf("With %d group(s), we have %llu blocks available.\n",
+		       groups, (unsigned long long) data_blocks);
+#endif
+
+	/*
+	 * if we need more group descriptors in order to accommodate our data
+	 * then we need to add them here
+	 */
+	blks_needed = data_needed;
+	while (blks_needed > data_blocks) {
+		blk64_t remainder = blks_needed - data_blocks;
+		dgrp_t extra_grps;
+
+		/* figure out how many more groups we need for the data */
+		extra_grps = ext2fs_div64_ceil(remainder,
+					       EXT2_BLOCKS_PER_GROUP(fs->super));
+
+		data_blocks += EXT2_GROUPS_TO_BLOCKS(fs->super, extra_grps);
+
+		/* ok we have to account for the last group */
+		overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
+		last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
+
+		grp = flex_groups;
+		groups += extra_grps;
+		if (!ext2fs_has_feature_flex_bg(fs->super))
+			flex_groups = groups;
+		else if (groups > flex_groups) {
+			dgrp_t r = groups & (flexbg_size - 1);
+
+			flex_groups = groups + flexbg_size - r;
+			if (flex_groups > fs->group_desc_count)
+				flex_groups = fs->group_desc_count;
+		}
+
+		for (; grp < flex_groups; grp++) {
+			overhead = calc_group_overhead(fs, grp,
+						       old_desc_blocks);
+
+			/*
+			 * again, we need to see how much data we cram into
+			 * all of the groups leading up to the last group
+			 */
+			if (grp < groups - 1)
+				last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
+					- overhead;
+
+			data_blocks -= overhead;
+		}
+
+#ifdef RESIZE2FS_DEBUG
+		if (flags & RESIZE_DEBUG_MIN_CALC)
+			printf("Added %d extra group(s), "
+			       "blks_needed %llu, data_blocks %llu, "
+			       "last_start %llu\n", extra_grps,
+			       (unsigned long long) blks_needed,
+			       (unsigned long long) data_blocks,
+			       (unsigned long long) last_start);
+#endif
+	}
+
+	/* now for the fun voodoo */
+	grp = groups - 1;
+	if (ext2fs_has_feature_flex_bg(fs->super) &&
+	    (grp & ~(flexbg_size - 1)) == 0)
+		grp = grp & ~(flexbg_size - 1);
+	overhead = 0;
+	for (; grp < flex_groups; grp++)
+		overhead += calc_group_overhead(fs, grp, old_desc_blocks);
+
+#ifdef RESIZE2FS_DEBUG
+	if (flags & RESIZE_DEBUG_MIN_CALC)
+		printf("Last group's overhead is %llu\n",
+		       (unsigned long long) overhead);
+#endif
+
+	/*
+	 * if this is the case then the last group is going to have data in it
+	 * so we need to adjust the size of the last group accordingly
+	 */
+	if (last_start < blks_needed) {
+		blk64_t remainder = blks_needed - last_start;
+
+#ifdef RESIZE2FS_DEBUG
+		if (flags & RESIZE_DEBUG_MIN_CALC)
+			printf("Need %llu data blocks in last group\n",
+			       (unsigned long long) remainder);
+#endif
+		/*
+		 * 50 is a magic number that mkfs/resize uses to see if its
+		 * even worth making/resizing the fs.  basically you need to
+		 * have at least 50 blocks in addition to the blocks needed
+		 * for the metadata in the last group
+		 */
+		if (remainder > 50)
+			overhead += remainder;
+		else
+			overhead += 50;
+	} else
+		overhead += 50;
+
+	overhead += fs->super->s_first_data_block;
+#ifdef RESIZE2FS_DEBUG
+	if (flags & RESIZE_DEBUG_MIN_CALC)
+		printf("Final size of last group is %llu\n",
+		       (unsigned long long) overhead);
+#endif
+
+	/* Add extra slack for bigalloc file systems */
+	if (EXT2FS_CLUSTER_RATIO(fs) > 1)
+		overhead += EXT2FS_CLUSTER_RATIO(fs) * 2;
+
+	/*
+	 * since our last group doesn't have to be BLOCKS_PER_GROUP
+	 * large, we only do groups-1, and then add the number of
+	 * blocks needed to handle the group descriptor metadata+data
+	 * that we need
+	 */
+	blks_needed = EXT2_GROUPS_TO_BLOCKS(fs->super, groups - 1);
+	blks_needed += overhead;
+
+	/*
+	 * Make sure blks_needed covers the end of the inode table in
+	 * the last block group.
+	 */
+	overhead = ext2fs_inode_table_loc(fs, groups-1) +
+		fs->inode_blocks_per_group;
+	if (blks_needed < overhead)
+		blks_needed = overhead;
+
+#ifdef RESIZE2FS_DEBUG
+	if (flags & RESIZE_DEBUG_MIN_CALC)
+		printf("Estimated blocks needed: %llu\n",
+		       (unsigned long long) blks_needed);
+#endif
+
+	/*
+	 * If at this point we've already added up more "needed" than
+	 * the current size, just return current size as minimum.
+	 */
+	if (blks_needed >= ext2fs_blocks_count(fs->super))
+		return ext2fs_blocks_count(fs->super);
+	/*
+	 * We need to reserve a few extra blocks if extents are
+	 * enabled, in case we need to grow the extent tree.  The more
+	 * we shrink the file system, the more space we need.
+	 *
+	 * The absolute worst case is every single data block is in
+	 * the part of the file system that needs to be evacuated,
+	 * with each data block needs to be in its own extent, and
+	 * with each inode needing at least one extent block.
+	 */
+	if (ext2fs_has_feature_extents(fs->super)) {
+		blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
+				       blks_needed)/500;
+		unsigned int exts_per_blk = (fs->blocksize /
+					     sizeof(struct ext3_extent)) - 1;
+		blk64_t worst_case = ((data_needed + exts_per_blk - 1) /
+				      exts_per_blk);
+
+		if (worst_case < inode_count)
+			worst_case = inode_count;
+
+		if (safe_margin > worst_case)
+			safe_margin = worst_case;
+
+#ifdef RESIZE2FS_DEBUG
+		if (flags & RESIZE_DEBUG_MIN_CALC)
+			printf("Extents safety margin: %llu\n",
+			       (unsigned long long) safe_margin);
+#endif
+		blks_needed += safe_margin;
+	}
+
+	return blks_needed;
+}