lib/ext2fs/rw_bitmaps.c - pub/scm/linux/kernel/git/djwong/e2fsprogs - Git at Google

 /*
  * rw_bitmaps.c --- routines to read and write the  inode and block bitmaps.
  *
  * Copyright (C) 1993, 1994, 1994, 1996 Theodore Ts'o.
  *
  * %Begin-Header%
  * This file may be redistributed under the terms of the GNU Library
  * General Public License, version 2.
  * %End-Header%
  */

 #include "config.h"
 #include <stdio.h>
 #include <string.h>
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
 #include <fcntl.h>
 #include <time.h>
 #ifdef HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif

 #include "ext2_fs.h"
 #include "ext2fs.h"
 #include "e2image.h"

 static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
 {
 	dgrp_t 		i;
 	unsigned int	j;
 	int		block_nbytes, inode_nbytes;
 	unsigned int	nbits;
 	errcode_t	retval;
 	char		*block_buf = NULL, *inode_buf = NULL;
 	int		csum_flag;
 	blk64_t		blk;
 	blk64_t		blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
 	ext2_ino_t	ino_itr = 1;

 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

 	if (!(fs->flags & EXT2_FLAG_RW))
 		return EXT2_ET_RO_FILSYS;

 	csum_flag = ext2fs_has_group_desc_csum(fs);

 	inode_nbytes = block_nbytes = 0;
 	if (do_block) {
 		block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
 		retval = io_channel_alloc_buf(fs->io, 0, &block_buf);
 		if (retval)
 			goto errout;
 		memset(block_buf, 0xff, fs->blocksize);
 	}
 	if (do_inode) {
 		inode_nbytes = (size_t)
 			((EXT2_INODES_PER_GROUP(fs->super)+7) / 8);
 		retval = io_channel_alloc_buf(fs->io, 0, &inode_buf);
 		if (retval)
 			goto errout;
 		memset(inode_buf, 0xff, fs->blocksize);
 	}

 	for (i = 0; i < fs->group_desc_count; i++) {
 		if (!do_block)
 			goto skip_block_bitmap;

 		if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT)
 		    )
 			goto skip_this_block_bitmap;

 		retval = ext2fs_get_block_bitmap_range2(fs->block_map,
 				blk_itr, block_nbytes << 3, block_buf);
 		if (retval)
 			goto errout;

 		if (i == fs->group_desc_count - 1) {
 			/* Force bitmap padding for the last group */
 			nbits = EXT2FS_NUM_B2C(fs,
 				((ext2fs_blocks_count(fs->super)
 				  - (__u64) fs->super->s_first_data_block)
 				 % (__u64) EXT2_BLOCKS_PER_GROUP(fs->super)));
 			if (nbits)
 				for (j = nbits; j < fs->blocksize * 8; j++)
 					ext2fs_set_bit(j, block_buf);
 		}

 		retval = ext2fs_block_bitmap_csum_set(fs, i, block_buf,
 						      block_nbytes);
 		if (retval)
 			return retval;
 		ext2fs_group_desc_csum_set(fs, i);

 		blk = ext2fs_block_bitmap_loc(fs, i);
 		if (blk) {
 			retval = io_channel_write_blk64(fs->io, blk, 1,
 							block_buf);
 			if (retval) {
 				retval = EXT2_ET_BLOCK_BITMAP_WRITE;
 				goto errout;
 			}
 		}
 	skip_this_block_bitmap:
 		blk_itr += block_nbytes << 3;
 	skip_block_bitmap:

 		if (!do_inode)
 			continue;

 		if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT)
 		    )
 			goto skip_this_inode_bitmap;

 		retval = ext2fs_get_inode_bitmap_range2(fs->inode_map,
 				ino_itr, inode_nbytes << 3, inode_buf);
 		if (retval)
 			goto errout;

 		retval = ext2fs_inode_bitmap_csum_set(fs, i, inode_buf,
 						      inode_nbytes);
 		if (retval)
 			goto errout;
 		ext2fs_group_desc_csum_set(fs, i);

 		blk = ext2fs_inode_bitmap_loc(fs, i);
 		if (blk) {
 			retval = io_channel_write_blk64(fs->io, blk, 1,
 						      inode_buf);
 			if (retval) {
 				retval = EXT2_ET_INODE_BITMAP_WRITE;
 				goto errout;
 			}
 		}
 	skip_this_inode_bitmap:
 		ino_itr += inode_nbytes << 3;

 	}
 	if (do_block) {
 		fs->flags &= ~EXT2_FLAG_BB_DIRTY;
 		ext2fs_free_mem(&block_buf);
 	}
 	if (do_inode) {
 		fs->flags &= ~EXT2_FLAG_IB_DIRTY;
 		ext2fs_free_mem(&inode_buf);
 	}
 	return 0;
 errout:
 	if (inode_buf)
 		ext2fs_free_mem(&inode_buf);
 	if (block_buf)
 		ext2fs_free_mem(&block_buf);
 	return retval;
 }

 static errcode_t mark_uninit_bg_group_blocks(ext2_filsys fs)
 {
 	dgrp_t			i;
 	blk64_t			blk;
 	ext2fs_block_bitmap	bmap = fs->block_map;

 	for (i = 0; i < fs->group_desc_count; i++) {
 		if (!ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT))
 			continue;

 		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);
 	}
 	return 0;
 }

 static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
 {
 	dgrp_t i;
 	char *block_bitmap = 0, *inode_bitmap = 0;
 	char *buf;
 	errcode_t retval;
 	int block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
 	int inode_nbytes = EXT2_INODES_PER_GROUP(fs->super) / 8;
 	int csum_flag;
 	unsigned int	cnt;
 	blk64_t	blk;
 	blk64_t	blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
 	blk64_t   blk_cnt;
 	ext2_ino_t ino_itr = 1;
 	ext2_ino_t ino_cnt;

 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

 	if ((block_nbytes > (int) fs->blocksize) ||
 	    (inode_nbytes > (int) fs->blocksize))
 		return EXT2_ET_CORRUPT_SUPERBLOCK;

 	fs->write_bitmaps = ext2fs_write_bitmaps;

 	csum_flag = ext2fs_has_group_desc_csum(fs);

 	retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf);
 	if (retval)
 		return retval;
 	if (do_block) {
 		if (fs->block_map)
 			ext2fs_free_block_bitmap(fs->block_map);
 		strcpy(buf, "block bitmap for ");
 		strcat(buf, fs->device_name);
 		retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map);
 		if (retval)
 			goto cleanup;
 		retval = io_channel_alloc_buf(fs->io, 0, &block_bitmap);
 		if (retval)
 			goto cleanup;
 	} else
 		block_nbytes = 0;
 	if (do_inode) {
 		if (fs->inode_map)
 			ext2fs_free_inode_bitmap(fs->inode_map);
 		strcpy(buf, "inode bitmap for ");
 		strcat(buf, fs->device_name);
 		retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map);
 		if (retval)
 			goto cleanup;
 		retval = io_channel_alloc_buf(fs->io, 0, &inode_bitmap);
 		if (retval)
 			goto cleanup;
 	} else
 		inode_nbytes = 0;
 	ext2fs_free_mem(&buf);

 	if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
 		blk = (fs->image_header->offset_inodemap / fs->blocksize);
 		ino_cnt = fs->super->s_inodes_count;
 		while (inode_nbytes > 0) {
 			retval = io_channel_read_blk64(fs->image_io, blk++,
 						     1, inode_bitmap);
 			if (retval)
 				goto cleanup;
 			cnt = fs->blocksize << 3;
 			if (cnt > ino_cnt)
 				cnt = ino_cnt;
 			retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
 					       ino_itr, cnt, inode_bitmap);
 			if (retval)
 				goto cleanup;
 			ino_itr += fs->blocksize << 3;
 			ino_cnt -= fs->blocksize << 3;
 			inode_nbytes -= fs->blocksize;
 		}
 		blk = (fs->image_header->offset_blockmap /
 		       fs->blocksize);
 		blk_cnt = EXT2_GROUPS_TO_CLUSTERS(fs->super,
 						  fs->group_desc_count);
 		while (block_nbytes > 0) {
 			retval = io_channel_read_blk64(fs->image_io, blk++,
 						     1, block_bitmap);
 			if (retval)
 				goto cleanup;
 			cnt = fs->blocksize << 3;
 			if (cnt > blk_cnt)
 				cnt = blk_cnt;
 			retval = ext2fs_set_block_bitmap_range2(fs->block_map,
 				       blk_itr, cnt, block_bitmap);
 			if (retval)
 				goto cleanup;
 			blk_itr += fs->blocksize << 3;
 			blk_cnt -= fs->blocksize << 3;
 			block_nbytes -= fs->blocksize;
 		}
 		goto success_cleanup;
 	}

 	for (i = 0; i < fs->group_desc_count; i++) {
 		if (block_bitmap) {
 			blk = ext2fs_block_bitmap_loc(fs, i);
 			if (csum_flag &&
 			    ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT) &&
 			    ext2fs_group_desc_csum_verify(fs, i))
 				blk = 0;
 			if (blk) {
 				retval = io_channel_read_blk64(fs->io, blk,
 							       1, block_bitmap);
 				if (retval) {
 					retval = EXT2_ET_BLOCK_BITMAP_READ;
 					goto cleanup;
 				}
 				/* verify block bitmap checksum */
 				if (!(fs->flags &
 				      EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
 				    !ext2fs_block_bitmap_csum_verify(fs, i,
 						block_bitmap, block_nbytes)) {
 					retval =
 					EXT2_ET_BLOCK_BITMAP_CSUM_INVALID;
 					goto cleanup;
 				}
 			} else
 				memset(block_bitmap, 0, block_nbytes);
 			cnt = block_nbytes << 3;
 			retval = ext2fs_set_block_bitmap_range2(fs->block_map,
 					       blk_itr, cnt, block_bitmap);
 			if (retval)
 				goto cleanup;
 			blk_itr += block_nbytes << 3;
 		}
 		if (inode_bitmap) {
 			blk = ext2fs_inode_bitmap_loc(fs, i);
 			if (csum_flag &&
 			    ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT) &&
 			    ext2fs_group_desc_csum_verify(fs, i))
 				blk = 0;
 			if (blk) {
 				retval = io_channel_read_blk64(fs->io, blk,
 							       1, inode_bitmap);
 				if (retval) {
 					retval = EXT2_ET_INODE_BITMAP_READ;
 					goto cleanup;
 				}

 				/* verify inode bitmap checksum */
 				if (!(fs->flags &
 				      EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
 				    !ext2fs_inode_bitmap_csum_verify(fs, i,
 						inode_bitmap, inode_nbytes)) {
 					retval =
 					EXT2_ET_INODE_BITMAP_CSUM_INVALID;
 					goto cleanup;
 				}
 			} else
 				memset(inode_bitmap, 0, inode_nbytes);
 			cnt = inode_nbytes << 3;
 			retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
 					       ino_itr, cnt, inode_bitmap);
 			if (retval)
 				goto cleanup;
 			ino_itr += inode_nbytes << 3;
 		}
 	}

 	/* Mark group blocks for any BLOCK_UNINIT groups */
 	if (do_block) {
 		retval = mark_uninit_bg_group_blocks(fs);
 		if (retval)
 			goto cleanup;
 	}

 success_cleanup:
 	if (inode_bitmap)
 		ext2fs_free_mem(&inode_bitmap);
 	if (block_bitmap)
 		ext2fs_free_mem(&block_bitmap);
 	return 0;

 cleanup:
 	if (do_block) {
 		ext2fs_free_mem(&fs->block_map);
 		fs->block_map = 0;
 	}
 	if (do_inode) {
 		ext2fs_free_mem(&fs->inode_map);
 		fs->inode_map = 0;
 	}
 	if (inode_bitmap)
 		ext2fs_free_mem(&inode_bitmap);
 	if (block_bitmap)
 		ext2fs_free_mem(&block_bitmap);
 	if (buf)
 		ext2fs_free_mem(&buf);
 	return retval;
 }

 errcode_t ext2fs_read_inode_bitmap(ext2_filsys fs)
 {
 	return read_bitmaps(fs, 1, 0);
 }

 errcode_t ext2fs_read_block_bitmap(ext2_filsys fs)
 {
 	return read_bitmaps(fs, 0, 1);
 }

 errcode_t ext2fs_write_inode_bitmap(ext2_filsys fs)
 {
 	return write_bitmaps(fs, 1, 0);
 }

 errcode_t ext2fs_write_block_bitmap (ext2_filsys fs)
 {
 	return write_bitmaps(fs, 0, 1);
 }

 errcode_t ext2fs_read_bitmaps(ext2_filsys fs)
 {
 	if (fs->inode_map && fs->block_map)
 		return 0;

 	return read_bitmaps(fs, !fs->inode_map, !fs->block_map);
 }

 errcode_t ext2fs_write_bitmaps(ext2_filsys fs)
 {
 	int do_inode = fs->inode_map && ext2fs_test_ib_dirty(fs);
 	int do_block = fs->block_map && ext2fs_test_bb_dirty(fs);

 	if (!do_inode && !do_block)
 		return 0;

 	return write_bitmaps(fs, do_inode, do_block);
 }
	/*
	* rw_bitmaps.c --- routines to read and write the inode and block bitmaps.
	*
	* Copyright (C) 1993, 1994, 1994, 1996 Theodore Ts'o.
	*
	* %Begin-Header%
	* This file may be redistributed under the terms of the GNU Library
	* General Public License, version 2.
	* %End-Header%
	*/

	#include "config.h"
	#include <stdio.h>
	#include <string.h>
	#if HAVE_UNISTD_H
	#include <unistd.h>
	#endif
	#include <fcntl.h>
	#include <time.h>
	#ifdef HAVE_SYS_STAT_H
	#include <sys/stat.h>
	#endif
	#ifdef HAVE_SYS_TYPES_H
	#include <sys/types.h>
	#endif

	#include "ext2_fs.h"
	#include "ext2fs.h"
	#include "e2image.h"

	static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
	{
	dgrp_t i;
	unsigned int j;
	int block_nbytes, inode_nbytes;
	unsigned int nbits;
	errcode_t retval;
	char block_buf = NULL, inode_buf = NULL;
	int csum_flag;
	blk64_t blk;
	blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
	ext2_ino_t ino_itr = 1;

	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

	if (!(fs->flags & EXT2_FLAG_RW))
	return EXT2_ET_RO_FILSYS;

	csum_flag = ext2fs_has_group_desc_csum(fs);

	inode_nbytes = block_nbytes = 0;
	if (do_block) {
	block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
	retval = io_channel_alloc_buf(fs->io, 0, &block_buf);
	if (retval)
	goto errout;
	memset(block_buf, 0xff, fs->blocksize);
	}
	if (do_inode) {
	inode_nbytes = (size_t)
	((EXT2_INODES_PER_GROUP(fs->super)+7) / 8);
	retval = io_channel_alloc_buf(fs->io, 0, &inode_buf);
	if (retval)
	goto errout;
	memset(inode_buf, 0xff, fs->blocksize);
	}

	for (i = 0; i < fs->group_desc_count; i++) {
	if (!do_block)
	goto skip_block_bitmap;

	if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT)
	)
	goto skip_this_block_bitmap;

	retval = ext2fs_get_block_bitmap_range2(fs->block_map,
	blk_itr, block_nbytes << 3, block_buf);
	if (retval)
	goto errout;

	if (i == fs->group_desc_count - 1) {
	/* Force bitmap padding for the last group */
	nbits = EXT2FS_NUM_B2C(fs,
	((ext2fs_blocks_count(fs->super)
	- (__u64) fs->super->s_first_data_block)
	% (__u64) EXT2_BLOCKS_PER_GROUP(fs->super)));
	if (nbits)
	for (j = nbits; j < fs->blocksize * 8; j++)
	ext2fs_set_bit(j, block_buf);
	}

	retval = ext2fs_block_bitmap_csum_set(fs, i, block_buf,
	block_nbytes);
	if (retval)
	return retval;
	ext2fs_group_desc_csum_set(fs, i);

	blk = ext2fs_block_bitmap_loc(fs, i);
	if (blk) {
	retval = io_channel_write_blk64(fs->io, blk, 1,
	block_buf);
	if (retval) {
	retval = EXT2_ET_BLOCK_BITMAP_WRITE;
	goto errout;
	}
	}
	skip_this_block_bitmap:
	blk_itr += block_nbytes << 3;
	skip_block_bitmap:

	if (!do_inode)
	continue;

	if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT)
	)
	goto skip_this_inode_bitmap;

	retval = ext2fs_get_inode_bitmap_range2(fs->inode_map,
	ino_itr, inode_nbytes << 3, inode_buf);
	if (retval)
	goto errout;

	retval = ext2fs_inode_bitmap_csum_set(fs, i, inode_buf,
	inode_nbytes);
	if (retval)
	goto errout;
	ext2fs_group_desc_csum_set(fs, i);

	blk = ext2fs_inode_bitmap_loc(fs, i);
	if (blk) {
	retval = io_channel_write_blk64(fs->io, blk, 1,
	inode_buf);
	if (retval) {
	retval = EXT2_ET_INODE_BITMAP_WRITE;
	goto errout;
	}
	}
	skip_this_inode_bitmap:
	ino_itr += inode_nbytes << 3;

	}
	if (do_block) {
	fs->flags &= ~EXT2_FLAG_BB_DIRTY;
	ext2fs_free_mem(&block_buf);
	}
	if (do_inode) {
	fs->flags &= ~EXT2_FLAG_IB_DIRTY;
	ext2fs_free_mem(&inode_buf);
	}
	return 0;
	errout:
	if (inode_buf)
	ext2fs_free_mem(&inode_buf);
	if (block_buf)
	ext2fs_free_mem(&block_buf);
	return retval;
	}

	static errcode_t mark_uninit_bg_group_blocks(ext2_filsys fs)
	{
	dgrp_t i;
	blk64_t blk;
	ext2fs_block_bitmap bmap = fs->block_map;

	for (i = 0; i < fs->group_desc_count; i++) {
	if (!ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT))
	continue;

	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);
	}
	return 0;
	}

	static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
	{
	dgrp_t i;
	char block_bitmap = 0, inode_bitmap = 0;
	char *buf;
	errcode_t retval;
	int block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
	int inode_nbytes = EXT2_INODES_PER_GROUP(fs->super) / 8;
	int csum_flag;
	unsigned int cnt;
	blk64_t blk;
	blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
	blk64_t blk_cnt;
	ext2_ino_t ino_itr = 1;
	ext2_ino_t ino_cnt;

	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);

	if ((block_nbytes > (int) fs->blocksize) \|\|
	(inode_nbytes > (int) fs->blocksize))
	return EXT2_ET_CORRUPT_SUPERBLOCK;

	fs->write_bitmaps = ext2fs_write_bitmaps;

	csum_flag = ext2fs_has_group_desc_csum(fs);

	retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf);
	if (retval)
	return retval;
	if (do_block) {
	if (fs->block_map)
	ext2fs_free_block_bitmap(fs->block_map);
	strcpy(buf, "block bitmap for ");
	strcat(buf, fs->device_name);
	retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map);
	if (retval)
	goto cleanup;
	retval = io_channel_alloc_buf(fs->io, 0, &block_bitmap);
	if (retval)
	goto cleanup;
	} else
	block_nbytes = 0;
	if (do_inode) {
	if (fs->inode_map)
	ext2fs_free_inode_bitmap(fs->inode_map);
	strcpy(buf, "inode bitmap for ");
	strcat(buf, fs->device_name);
	retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map);
	if (retval)
	goto cleanup;
	retval = io_channel_alloc_buf(fs->io, 0, &inode_bitmap);
	if (retval)
	goto cleanup;
	} else
	inode_nbytes = 0;
	ext2fs_free_mem(&buf);

	if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
	blk = (fs->image_header->offset_inodemap / fs->blocksize);
	ino_cnt = fs->super->s_inodes_count;
	while (inode_nbytes > 0) {
	retval = io_channel_read_blk64(fs->image_io, blk++,
	1, inode_bitmap);
	if (retval)
	goto cleanup;
	cnt = fs->blocksize << 3;
	if (cnt > ino_cnt)
	cnt = ino_cnt;
	retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
	ino_itr, cnt, inode_bitmap);
	if (retval)
	goto cleanup;
	ino_itr += fs->blocksize << 3;
	ino_cnt -= fs->blocksize << 3;
	inode_nbytes -= fs->blocksize;
	}
	blk = (fs->image_header->offset_blockmap /
	fs->blocksize);
	blk_cnt = EXT2_GROUPS_TO_CLUSTERS(fs->super,
	fs->group_desc_count);
	while (block_nbytes > 0) {
	retval = io_channel_read_blk64(fs->image_io, blk++,
	1, block_bitmap);
	if (retval)
	goto cleanup;
	cnt = fs->blocksize << 3;
	if (cnt > blk_cnt)
	cnt = blk_cnt;
	retval = ext2fs_set_block_bitmap_range2(fs->block_map,
	blk_itr, cnt, block_bitmap);
	if (retval)
	goto cleanup;
	blk_itr += fs->blocksize << 3;
	blk_cnt -= fs->blocksize << 3;
	block_nbytes -= fs->blocksize;
	}
	goto success_cleanup;
	}

	for (i = 0; i < fs->group_desc_count; i++) {
	if (block_bitmap) {
	blk = ext2fs_block_bitmap_loc(fs, i);
	if (csum_flag &&
	ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT) &&
	ext2fs_group_desc_csum_verify(fs, i))
	blk = 0;
	if (blk) {
	retval = io_channel_read_blk64(fs->io, blk,
	1, block_bitmap);
	if (retval) {
	retval = EXT2_ET_BLOCK_BITMAP_READ;
	goto cleanup;
	}
	/* verify block bitmap checksum */
	if (!(fs->flags &
	EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
	!ext2fs_block_bitmap_csum_verify(fs, i,
	block_bitmap, block_nbytes)) {
	retval =
	EXT2_ET_BLOCK_BITMAP_CSUM_INVALID;
	goto cleanup;
	}
	} else
	memset(block_bitmap, 0, block_nbytes);
	cnt = block_nbytes << 3;
	retval = ext2fs_set_block_bitmap_range2(fs->block_map,
	blk_itr, cnt, block_bitmap);
	if (retval)
	goto cleanup;
	blk_itr += block_nbytes << 3;
	}
	if (inode_bitmap) {
	blk = ext2fs_inode_bitmap_loc(fs, i);
	if (csum_flag &&
	ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT) &&
	ext2fs_group_desc_csum_verify(fs, i))
	blk = 0;
	if (blk) {
	retval = io_channel_read_blk64(fs->io, blk,
	1, inode_bitmap);
	if (retval) {
	retval = EXT2_ET_INODE_BITMAP_READ;
	goto cleanup;
	}

	/* verify inode bitmap checksum */
	if (!(fs->flags &
	EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
	!ext2fs_inode_bitmap_csum_verify(fs, i,
	inode_bitmap, inode_nbytes)) {
	retval =
	EXT2_ET_INODE_BITMAP_CSUM_INVALID;
	goto cleanup;
	}
	} else
	memset(inode_bitmap, 0, inode_nbytes);
	cnt = inode_nbytes << 3;
	retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
	ino_itr, cnt, inode_bitmap);
	if (retval)
	goto cleanup;
	ino_itr += inode_nbytes << 3;
	}
	}

	/* Mark group blocks for any BLOCK_UNINIT groups */
	if (do_block) {
	retval = mark_uninit_bg_group_blocks(fs);
	if (retval)
	goto cleanup;
	}

	success_cleanup:
	if (inode_bitmap)
	ext2fs_free_mem(&inode_bitmap);
	if (block_bitmap)
	ext2fs_free_mem(&block_bitmap);
	return 0;

	cleanup:
	if (do_block) {
	ext2fs_free_mem(&fs->block_map);
	fs->block_map = 0;
	}
	if (do_inode) {
	ext2fs_free_mem(&fs->inode_map);
	fs->inode_map = 0;
	}
	if (inode_bitmap)
	ext2fs_free_mem(&inode_bitmap);
	if (block_bitmap)
	ext2fs_free_mem(&block_bitmap);
	if (buf)
	ext2fs_free_mem(&buf);
	return retval;
	}

	errcode_t ext2fs_read_inode_bitmap(ext2_filsys fs)
	{
	return read_bitmaps(fs, 1, 0);
	}

	errcode_t ext2fs_read_block_bitmap(ext2_filsys fs)
	{
	return read_bitmaps(fs, 0, 1);
	}

	errcode_t ext2fs_write_inode_bitmap(ext2_filsys fs)
	{
	return write_bitmaps(fs, 1, 0);
	}

	errcode_t ext2fs_write_block_bitmap (ext2_filsys fs)
	{
	return write_bitmaps(fs, 0, 1);
	}

	errcode_t ext2fs_read_bitmaps(ext2_filsys fs)
	{
	if (fs->inode_map && fs->block_map)
	return 0;

	return read_bitmaps(fs, !fs->inode_map, !fs->block_map);
	}

	errcode_t ext2fs_write_bitmaps(ext2_filsys fs)
	{
	int do_inode = fs->inode_map && ext2fs_test_ib_dirty(fs);
	int do_block = fs->block_map && ext2fs_test_bb_dirty(fs);

	if (!do_inode && !do_block)
	return 0;

	return write_bitmaps(fs, do_inode, do_block);
	}