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  • 		if (le16_to_cpu(bgd[bg_idx].bg_flags) & EXT4_BG_BLOCK_UNINIT) {
    			uint16_t new_flags;
    			put_ext4((uint64_t)le32_to_cpu(bgd[bg_idx].block_id) * fs->blksz,
    				 zero_buffer, fs->blksz);
    
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    			memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
    
    			new_flags = le16_to_cpu(bgd[bg_idx].bg_flags) & ~EXT4_BG_BLOCK_UNINIT;
    			bgd[bg_idx].bg_flags = cpu_to_le16(new_flags);
    
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    		}
    
    		if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
    				   bg_idx) != 0) {
    			debug("going for restart for the block no %ld %u\n",
    			      fs->curr_blkno, bg_idx);
    
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    			goto restart;
    		}
    
    		/* journal backup */
    		if (prev_bg_bitmap_index != bg_idx) {
    
    			status = ext4fs_devread(
    						(lbaint_t)le32_to_cpu(bgd[bg_idx].block_id)
    
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    						* fs->sect_perblk,
    						0, fs->blksz, journal_buffer);
    			if (status == 0)
    				goto fail;
    			if (ext4fs_log_journal(journal_buffer,
    
    						le32_to_cpu(bgd[bg_idx].block_id)))
    
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    				goto fail;
    
    			prev_bg_bitmap_index = bg_idx;
    		}
    
    		ext4fs_bg_free_blocks_dec(&bgd[bg_idx]);
    		ext4fs_sb_free_blocks_dec(fs->sb);
    
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    		goto success;
    	}
    success:
    	free(journal_buffer);
    	free(zero_buffer);
    
    	return fs->curr_blkno;
    fail:
    	free(journal_buffer);
    	free(zero_buffer);
    
    	return -1;
    }
    
    int ext4fs_get_new_inode_no(void)
    {
    	short i;
    	short status;
    	unsigned int ibmap_idx;
    	static int prev_inode_bitmap_index = -1;
    
    	unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
    
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    	struct ext_filesystem *fs = get_fs();
    	char *journal_buffer = zalloc(fs->blksz);
    	char *zero_buffer = zalloc(fs->blksz);
    	if (!journal_buffer || !zero_buffer)
    		goto fail;
    
    	struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
    
    	int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) &
    		EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0;
    
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    	if (fs->first_pass_ibmap == 0) {
    		for (i = 0; i < fs->no_blkgrp; i++) {
    
    			if (bgd[i].free_inodes) {
    
    					bgd[i].bg_itable_unused =
    						bgd[i].free_inodes;
    
    				if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_INODE_UNINIT) {
    					int new_flags;
    					put_ext4((uint64_t)le32_to_cpu(bgd[i].inode_id) * fs->blksz,
    
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    						 zero_buffer, fs->blksz);
    
    					new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_INODE_UNINIT;
    					bgd[i].bg_flags = cpu_to_le16(new_flags);
    
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    					memcpy(fs->inode_bmaps[i],
    					       zero_buffer, fs->blksz);
    				}
    				fs->curr_inode_no =
    				    _get_new_inode_no(fs->inode_bmaps[i]);
    				if (fs->curr_inode_no == -1)
    					/* if block bitmap is completely fill */
    					continue;
    				fs->curr_inode_no = fs->curr_inode_no +
    							(i * inodes_per_grp);
    				fs->first_pass_ibmap++;
    
    				ext4fs_bg_free_inodes_dec(&bgd[i]);
    
    				if (has_gdt_chksum)
    					ext4fs_bg_itable_unused_dec(&bgd[i]);
    
    				ext4fs_sb_free_inodes_dec(fs->sb);
    				status = ext4fs_devread(
    							(lbaint_t)le32_to_cpu(bgd[i].inode_id) *
    
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    							fs->sect_perblk, 0,
    							fs->blksz,
    							journal_buffer);
    				if (status == 0)
    					goto fail;
    				if (ext4fs_log_journal(journal_buffer,
    
    							le32_to_cpu(bgd[i].inode_id)))
    
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    					goto fail;
    				goto success;
    			} else
    				debug("no inode left on block group %d\n", i);
    		}
    		goto fail;
    	} else {
    restart:
    		fs->curr_inode_no++;
    		/* get the blockbitmap index respective to blockno */
    		ibmap_idx = fs->curr_inode_no / inodes_per_grp;
    
    		if (le16_to_cpu(bgd[ibmap_idx].bg_flags) & EXT4_BG_INODE_UNINIT) {
    			int new_flags;
    			put_ext4((uint64_t)le32_to_cpu(bgd[ibmap_idx].inode_id) * fs->blksz,
    				 zero_buffer, fs->blksz);
    			new_flags = le16_to_cpu(bgd[ibmap_idx].bg_flags) & ~EXT4_BG_INODE_UNINIT;
    			bgd[ibmap_idx].bg_flags = cpu_to_le16(new_flags);
    
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    			memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
    				fs->blksz);
    		}
    
    		if (ext4fs_set_inode_bmap(fs->curr_inode_no,
    					  fs->inode_bmaps[ibmap_idx],
    					  ibmap_idx) != 0) {
    			debug("going for restart for the block no %d %u\n",
    			      fs->curr_inode_no, ibmap_idx);
    			goto restart;
    		}
    
    		/* journal backup */
    		if (prev_inode_bitmap_index != ibmap_idx) {
    			memset(journal_buffer, '\0', fs->blksz);
    
    			status = ext4fs_devread(
    						(lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id)
    
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    						* fs->sect_perblk,
    						0, fs->blksz, journal_buffer);
    			if (status == 0)
    				goto fail;
    			if (ext4fs_log_journal(journal_buffer,
    
    						le32_to_cpu(bgd[ibmap_idx].inode_id)))
    
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    				goto fail;
    			prev_inode_bitmap_index = ibmap_idx;
    		}
    
    		ext4fs_bg_free_inodes_dec(&bgd[ibmap_idx]);
    		if (has_gdt_chksum)
    
    			bgd[ibmap_idx].bg_itable_unused =
    					bgd[ibmap_idx].free_inodes;
    
    		ext4fs_sb_free_inodes_dec(fs->sb);
    
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    		goto success;
    	}
    
    success:
    	free(journal_buffer);
    	free(zero_buffer);
    
    	return fs->curr_inode_no;
    fail:
    	free(journal_buffer);
    	free(zero_buffer);
    
    	return -1;
    
    }
    
    
    static void alloc_single_indirect_block(struct ext2_inode *file_inode,
    					unsigned int *total_remaining_blocks,
    					unsigned int *no_blks_reqd)
    {
    	short i;
    	short status;
    	long int actual_block_no;
    	long int si_blockno;
    	/* si :single indirect */
    
    	__le32 *si_buffer = NULL;
    	__le32 *si_start_addr = NULL;
    
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    	struct ext_filesystem *fs = get_fs();
    
    	if (*total_remaining_blocks != 0) {
    		si_buffer = zalloc(fs->blksz);
    		if (!si_buffer) {
    			printf("No Memory\n");
    			return;
    		}
    		si_start_addr = si_buffer;
    		si_blockno = ext4fs_get_new_blk_no();
    		if (si_blockno == -1) {
    			printf("no block left to assign\n");
    			goto fail;
    		}
    		(*no_blks_reqd)++;
    		debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
    
    
    		status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
    
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    					0, fs->blksz, (char *)si_buffer);
    		memset(si_buffer, '\0', fs->blksz);
    		if (status == 0)
    			goto fail;
    
    		for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
    			actual_block_no = ext4fs_get_new_blk_no();
    			if (actual_block_no == -1) {
    				printf("no block left to assign\n");
    				goto fail;
    			}
    
    			*si_buffer = cpu_to_le32(actual_block_no);
    
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    			debug("SIAB %u: %u\n", *si_buffer,
    				*total_remaining_blocks);
    
    			si_buffer++;
    			(*total_remaining_blocks)--;
    			if (*total_remaining_blocks == 0)
    				break;
    		}
    
    		/* write the block to disk */
    
    		put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
    
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    			 si_start_addr, fs->blksz);
    
    		file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno);
    
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    	}
    fail:
    	free(si_start_addr);
    }
    
    static void alloc_double_indirect_block(struct ext2_inode *file_inode,
    					unsigned int *total_remaining_blocks,
    					unsigned int *no_blks_reqd)
    {
    	short i;
    	short j;
    	short status;
    	long int actual_block_no;
    	/* di:double indirect */
    	long int di_blockno_parent;
    	long int di_blockno_child;
    
    	__le32 *di_parent_buffer = NULL;
    	__le32 *di_child_buff = NULL;
    	__le32 *di_block_start_addr = NULL;
    	__le32 *di_child_buff_start = NULL;
    
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    	struct ext_filesystem *fs = get_fs();
    
    	if (*total_remaining_blocks != 0) {
    		/* double indirect parent block connecting to inode */
    		di_blockno_parent = ext4fs_get_new_blk_no();
    		if (di_blockno_parent == -1) {
    			printf("no block left to assign\n");
    			goto fail;
    		}
    		di_parent_buffer = zalloc(fs->blksz);
    		if (!di_parent_buffer)
    			goto fail;
    
    		di_block_start_addr = di_parent_buffer;
    		(*no_blks_reqd)++;
    		debug("DIPB %ld: %u\n", di_blockno_parent,
    		      *total_remaining_blocks);
    
    
    		status = ext4fs_devread((lbaint_t)di_blockno_parent *
    
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    					fs->sect_perblk, 0,
    					fs->blksz, (char *)di_parent_buffer);
    
    
    		if (!status) {
    			printf("%s: Device read error!\n", __func__);
    			goto fail;
    		}
    
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    		memset(di_parent_buffer, '\0', fs->blksz);
    
    		/*
    		 * start:for each double indirect parent
    		 * block create one more block
    		 */
    		for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
    			di_blockno_child = ext4fs_get_new_blk_no();
    			if (di_blockno_child == -1) {
    				printf("no block left to assign\n");
    				goto fail;
    			}
    			di_child_buff = zalloc(fs->blksz);
    			if (!di_child_buff)
    				goto fail;
    
    			di_child_buff_start = di_child_buff;
    
    			*di_parent_buffer = cpu_to_le32(di_blockno_child);
    
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    			di_parent_buffer++;
    			(*no_blks_reqd)++;
    			debug("DICB %ld: %u\n", di_blockno_child,
    			      *total_remaining_blocks);
    
    
    			status = ext4fs_devread((lbaint_t)di_blockno_child *
    
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    						fs->sect_perblk, 0,
    						fs->blksz,
    						(char *)di_child_buff);
    
    
    			if (!status) {
    				printf("%s: Device read error!\n", __func__);
    				goto fail;
    			}
    
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    			memset(di_child_buff, '\0', fs->blksz);
    			/* filling of actual datablocks for each child */
    			for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
    				actual_block_no = ext4fs_get_new_blk_no();
    				if (actual_block_no == -1) {
    					printf("no block left to assign\n");
    					goto fail;
    				}
    
    				*di_child_buff = cpu_to_le32(actual_block_no);
    
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    				debug("DIAB %ld: %u\n", actual_block_no,
    				      *total_remaining_blocks);
    
    				di_child_buff++;
    				(*total_remaining_blocks)--;
    				if (*total_remaining_blocks == 0)
    					break;
    			}
    			/* write the block  table */
    
    			put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
    
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    				 di_child_buff_start, fs->blksz);
    			free(di_child_buff_start);
    			di_child_buff_start = NULL;
    
    			if (*total_remaining_blocks == 0)
    				break;
    		}
    
    		put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
    
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    			 di_block_start_addr, fs->blksz);
    
    		file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent);
    
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    	}
    fail:
    	free(di_block_start_addr);
    }
    
    static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
    					unsigned int *total_remaining_blocks,
    					unsigned int *no_blks_reqd)
    {
    	short i;
    	short j;
    	short k;
    	long int actual_block_no;
    	/* ti: Triple Indirect */
    	long int ti_gp_blockno;
    	long int ti_parent_blockno;
    	long int ti_child_blockno;
    
    	__le32 *ti_gp_buff = NULL;
    	__le32 *ti_parent_buff = NULL;
    	__le32 *ti_child_buff = NULL;
    	__le32 *ti_gp_buff_start_addr = NULL;
    	__le32 *ti_pbuff_start_addr = NULL;
    	__le32 *ti_cbuff_start_addr = NULL;
    
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    	struct ext_filesystem *fs = get_fs();
    	if (*total_remaining_blocks != 0) {
    		/* triple indirect grand parent block connecting to inode */
    		ti_gp_blockno = ext4fs_get_new_blk_no();
    		if (ti_gp_blockno == -1) {
    			printf("no block left to assign\n");
    
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    		}
    		ti_gp_buff = zalloc(fs->blksz);
    		if (!ti_gp_buff)
    
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    		ti_gp_buff_start_addr = ti_gp_buff;
    		(*no_blks_reqd)++;
    		debug("TIGPB %ld: %u\n", ti_gp_blockno,
    		      *total_remaining_blocks);
    
    		/* for each 4 byte grand parent entry create one more block */
    		for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
    			ti_parent_blockno = ext4fs_get_new_blk_no();
    			if (ti_parent_blockno == -1) {
    				printf("no block left to assign\n");
    				goto fail;
    			}
    			ti_parent_buff = zalloc(fs->blksz);
    			if (!ti_parent_buff)
    				goto fail;
    
    			ti_pbuff_start_addr = ti_parent_buff;
    
    			*ti_gp_buff = cpu_to_le32(ti_parent_blockno);
    
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    			ti_gp_buff++;
    			(*no_blks_reqd)++;
    			debug("TIPB %ld: %u\n", ti_parent_blockno,
    			      *total_remaining_blocks);
    
    			/* for each 4 byte entry parent create one more block */
    			for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
    				ti_child_blockno = ext4fs_get_new_blk_no();
    				if (ti_child_blockno == -1) {
    					printf("no block left assign\n");
    
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    				}
    				ti_child_buff = zalloc(fs->blksz);
    				if (!ti_child_buff)
    
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    				ti_cbuff_start_addr = ti_child_buff;
    
    				*ti_parent_buff = cpu_to_le32(ti_child_blockno);
    
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    				ti_parent_buff++;
    				(*no_blks_reqd)++;
    				debug("TICB %ld: %u\n", ti_parent_blockno,
    				      *total_remaining_blocks);
    
    				/* fill actual datablocks for each child */
    				for (k = 0; k < (fs->blksz / sizeof(int));
    					k++) {
    					actual_block_no =
    					    ext4fs_get_new_blk_no();
    					if (actual_block_no == -1) {
    						printf("no block left\n");
    
    						free(ti_cbuff_start_addr);
    						goto fail1;
    
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    					}
    
    					*ti_child_buff = cpu_to_le32(actual_block_no);
    
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    					debug("TIAB %ld: %u\n", actual_block_no,
    					      *total_remaining_blocks);
    
    					ti_child_buff++;
    					(*total_remaining_blocks)--;
    					if (*total_remaining_blocks == 0)
    						break;
    				}
    				/* write the child block */
    
    				put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
    						      (uint64_t)fs->blksz)),
    
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    					 ti_cbuff_start_addr, fs->blksz);
    				free(ti_cbuff_start_addr);
    
    				if (*total_remaining_blocks == 0)
    					break;
    			}
    			/* write the parent block */
    
    			put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
    
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    				 ti_pbuff_start_addr, fs->blksz);
    			free(ti_pbuff_start_addr);
    
    			if (*total_remaining_blocks == 0)
    				break;
    		}
    		/* write the grand parent block */
    
    		put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
    
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    			 ti_gp_buff_start_addr, fs->blksz);
    
    		file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno);
    
    		free(ti_gp_buff_start_addr);
    		return;
    
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    	}
    
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    fail:
    	free(ti_gp_buff_start_addr);
    }
    
    void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
    				unsigned int total_remaining_blocks,
    				unsigned int *total_no_of_block)
    {
    	short i;
    	long int direct_blockno;
    	unsigned int no_blks_reqd = 0;
    
    	/* allocation of direct blocks */
    
    	for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
    
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    		direct_blockno = ext4fs_get_new_blk_no();
    		if (direct_blockno == -1) {
    			printf("no block left to assign\n");
    			return;
    		}
    
    		file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno);
    
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    		debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
    
    		total_remaining_blocks--;
    	}
    
    	alloc_single_indirect_block(file_inode, &total_remaining_blocks,
    				    &no_blks_reqd);
    	alloc_double_indirect_block(file_inode, &total_remaining_blocks,
    				    &no_blks_reqd);
    	alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
    				    &no_blks_reqd);
    	*total_no_of_block += no_blks_reqd;
    }
    
    #endif
    
    
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    static struct ext4_extent_header *ext4fs_get_extent_block
    	(struct ext2_data *data, char *buf,
    		struct ext4_extent_header *ext_block,
    		uint32_t fileblock, int log2_blksz)
    {
    	struct ext4_extent_idx *index;
    	unsigned long long block;
    
    	int blksz = EXT2_BLOCK_SIZE(data);
    
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    	int i;
    
    	while (1) {
    		index = (struct ext4_extent_idx *)(ext_block + 1);
    
    
    		if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
    
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    		if (ext_block->eh_depth == 0)
    			return ext_block;
    		i = -1;
    		do {
    			i++;
    
    			if (i >= le16_to_cpu(ext_block->eh_entries))
    
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    				break;
    
    		} while (fileblock >= le32_to_cpu(index[i].ei_block));
    
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    		if (--i < 0)
    
    		block = le16_to_cpu(index[i].ei_leaf_hi);
    
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    		block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
    
    
    		if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
    
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    			ext_block = (struct ext4_extent_header *)buf;
    		else
    
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    	}
    }
    
    static int ext4fs_blockgroup
    	(struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
    {
    	long int blkno;
    	unsigned int blkoff, desc_per_blk;
    
    	int log2blksz = get_fs()->dev_desc->log2blksz;
    
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    	desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
    
    
    	blkno = le32_to_cpu(data->sblock.first_data_block) + 1 +
    
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    			group / desc_per_blk;
    	blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
    
    	debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
    	      group, blkno, blkoff);
    
    
    	return ext4fs_devread((lbaint_t)blkno <<
    			      (LOG2_BLOCK_SIZE(data) - log2blksz),
    
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    			      blkoff, sizeof(struct ext2_block_group),
    			      (char *)blkgrp);
    }
    
    int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
    {
    	struct ext2_block_group blkgrp;
    	struct ext2_sblock *sblock = &data->sblock;
    	struct ext_filesystem *fs = get_fs();
    
    	int log2blksz = get_fs()->dev_desc->log2blksz;
    
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    	int inodes_per_block, status;
    	long int blkno;
    	unsigned int blkoff;
    
    	/* It is easier to calculate if the first inode is 0. */
    	ino--;
    
    	status = ext4fs_blockgroup(data, ino / le32_to_cpu
    
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    				   (sblock->inodes_per_group), &blkgrp);
    	if (status == 0)
    		return 0;
    
    	inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
    
    	blkno = le32_to_cpu(blkgrp.inode_table_id) +
    	    (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
    
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    	blkoff = (ino % inodes_per_block) * fs->inodesz;
    	/* Read the inode. */
    
    	status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
    				log2blksz), blkoff,
    
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    				sizeof(struct ext2_inode), (char *)inode);
    	if (status == 0)
    		return 0;
    
    	return 1;
    }
    
    long int read_allocated_block(struct ext2_inode *inode, int fileblock)
    {
    	long int blknr;
    	int blksz;
    	int log2_blksz;
    	int status;
    	long int rblock;
    	long int perblock_parent;
    	long int perblock_child;
    	unsigned long long start;
    	/* get the blocksize of the filesystem */
    	blksz = EXT2_BLOCK_SIZE(ext4fs_root);
    
    	log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
    		- get_fs()->dev_desc->log2blksz;
    
    
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    	if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
    		char *buf = zalloc(blksz);
    		if (!buf)
    			return -ENOMEM;
    		struct ext4_extent_header *ext_block;
    		struct ext4_extent *extent;
    		int i = -1;
    
    		ext_block =
    			ext4fs_get_extent_block(ext4fs_root, buf,
    						(struct ext4_extent_header *)
    						inode->b.blocks.dir_blocks,
    						fileblock, log2_blksz);
    
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    		if (!ext_block) {
    			printf("invalid extent block\n");
    			free(buf);
    			return -EINVAL;
    		}
    
    		extent = (struct ext4_extent *)(ext_block + 1);
    
    		do {
    			i++;
    
    			if (i >= le16_to_cpu(ext_block->eh_entries))
    
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    				break;
    		} while (fileblock >= le32_to_cpu(extent[i].ee_block));
    		if (--i >= 0) {
    			fileblock -= le32_to_cpu(extent[i].ee_block);
    
    			if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
    
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    				free(buf);
    				return 0;
    			}
    
    
    			start = le16_to_cpu(extent[i].ee_start_hi);
    
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    			start = (start << 32) +
    					le32_to_cpu(extent[i].ee_start_lo);
    			free(buf);
    			return fileblock + start;
    		}
    
    		printf("Extent Error\n");
    		free(buf);
    		return -1;
    	}
    
    	/* Direct blocks. */
    	if (fileblock < INDIRECT_BLOCKS)
    
    		blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
    
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    	/* Indirect. */
    	else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
    		if (ext4fs_indir1_block == NULL) {
    			ext4fs_indir1_block = zalloc(blksz);
    			if (ext4fs_indir1_block == NULL) {
    				printf("** SI ext2fs read block (indir 1)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_size = blksz;
    			ext4fs_indir1_blkno = -1;
    		}
    		if (blksz != ext4fs_indir1_size) {
    			free(ext4fs_indir1_block);
    			ext4fs_indir1_block = NULL;
    			ext4fs_indir1_size = 0;
    			ext4fs_indir1_blkno = -1;
    			ext4fs_indir1_block = zalloc(blksz);
    			if (ext4fs_indir1_block == NULL) {
    				printf("** SI ext2fs read block (indir 1):"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_size = blksz;
    		}
    
    		if ((le32_to_cpu(inode->b.blocks.indir_block) <<
    
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    		     log2_blksz) != ext4fs_indir1_blkno) {
    			status =
    
    			    ext4fs_devread((lbaint_t)le32_to_cpu
    
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    					   (inode->b.blocks.
    					    indir_block) << log2_blksz, 0,
    					   blksz, (char *)ext4fs_indir1_block);
    			if (status == 0) {
    				printf("** SI ext2fs read block (indir 1)"
    					"failed. **\n");
    
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    			}
    			ext4fs_indir1_blkno =
    
    				le32_to_cpu(inode->b.blocks.
    
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    					       indir_block) << log2_blksz;
    		}
    
    		blknr = le32_to_cpu(ext4fs_indir1_block
    
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    				      [fileblock - INDIRECT_BLOCKS]);
    	}
    	/* Double indirect. */
    	else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
    					(blksz / 4 + 1)))) {
    
    		long int perblock = blksz / 4;
    		long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
    
    		if (ext4fs_indir1_block == NULL) {
    			ext4fs_indir1_block = zalloc(blksz);
    			if (ext4fs_indir1_block == NULL) {
    				printf("** DI ext2fs read block (indir 2 1)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_size = blksz;
    			ext4fs_indir1_blkno = -1;
    		}
    		if (blksz != ext4fs_indir1_size) {
    			free(ext4fs_indir1_block);
    			ext4fs_indir1_block = NULL;
    			ext4fs_indir1_size = 0;
    			ext4fs_indir1_blkno = -1;
    			ext4fs_indir1_block = zalloc(blksz);
    			if (ext4fs_indir1_block == NULL) {
    				printf("** DI ext2fs read block (indir 2 1)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_size = blksz;
    		}
    
    		if ((le32_to_cpu(inode->b.blocks.double_indir_block) <<
    
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    		     log2_blksz) != ext4fs_indir1_blkno) {
    			status =
    
    			    ext4fs_devread((lbaint_t)le32_to_cpu
    
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    					   (inode->b.blocks.
    					    double_indir_block) << log2_blksz,
    					   0, blksz,
    					   (char *)ext4fs_indir1_block);
    			if (status == 0) {
    				printf("** DI ext2fs read block (indir 2 1)"
    					"failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_blkno =
    
    			    le32_to_cpu(inode->b.blocks.double_indir_block) <<
    
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    			    log2_blksz;
    		}
    
    		if (ext4fs_indir2_block == NULL) {
    			ext4fs_indir2_block = zalloc(blksz);
    			if (ext4fs_indir2_block == NULL) {
    				printf("** DI ext2fs read block (indir 2 2)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir2_size = blksz;
    			ext4fs_indir2_blkno = -1;
    		}
    		if (blksz != ext4fs_indir2_size) {
    			free(ext4fs_indir2_block);
    			ext4fs_indir2_block = NULL;
    			ext4fs_indir2_size = 0;
    			ext4fs_indir2_blkno = -1;
    			ext4fs_indir2_block = zalloc(blksz);
    			if (ext4fs_indir2_block == NULL) {
    				printf("** DI ext2fs read block (indir 2 2)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir2_size = blksz;
    		}
    
    		if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
    
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    		     log2_blksz) != ext4fs_indir2_blkno) {
    
    			status = ext4fs_devread((lbaint_t)le32_to_cpu
    
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    						(ext4fs_indir1_block
    						 [rblock /
    						  perblock]) << log2_blksz, 0,
    						blksz,
    						(char *)ext4fs_indir2_block);
    			if (status == 0) {
    				printf("** DI ext2fs read block (indir 2 2)"
    					"failed. **\n");
    				return -1;
    			}
    			ext4fs_indir2_blkno =
    
    			    le32_to_cpu(ext4fs_indir1_block[rblock
    
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    							      /
    							      perblock]) <<
    			    log2_blksz;
    		}
    
    		blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
    
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    	}
    	/* Tripple indirect. */
    	else {
    		rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
    				      (blksz / 4 * blksz / 4));
    		perblock_child = blksz / 4;
    		perblock_parent = ((blksz / 4) * (blksz / 4));
    
    		if (ext4fs_indir1_block == NULL) {
    			ext4fs_indir1_block = zalloc(blksz);
    			if (ext4fs_indir1_block == NULL) {
    				printf("** TI ext2fs read block (indir 2 1)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_size = blksz;
    			ext4fs_indir1_blkno = -1;
    		}
    		if (blksz != ext4fs_indir1_size) {
    			free(ext4fs_indir1_block);
    			ext4fs_indir1_block = NULL;
    			ext4fs_indir1_size = 0;
    			ext4fs_indir1_blkno = -1;
    			ext4fs_indir1_block = zalloc(blksz);
    			if (ext4fs_indir1_block == NULL) {
    				printf("** TI ext2fs read block (indir 2 1)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_size = blksz;
    		}
    
    		if ((le32_to_cpu(inode->b.blocks.triple_indir_block) <<
    
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    		     log2_blksz) != ext4fs_indir1_blkno) {
    			status = ext4fs_devread
    
    			     le32_to_cpu(inode->b.blocks.triple_indir_block)
    
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    			     << log2_blksz, 0, blksz,
    			     (char *)ext4fs_indir1_block);
    			if (status == 0) {
    				printf("** TI ext2fs read block (indir 2 1)"
    					"failed. **\n");
    				return -1;
    			}
    			ext4fs_indir1_blkno =
    
    			    le32_to_cpu(inode->b.blocks.triple_indir_block) <<
    
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    			    log2_blksz;
    		}
    
    		if (ext4fs_indir2_block == NULL) {
    			ext4fs_indir2_block = zalloc(blksz);
    			if (ext4fs_indir2_block == NULL) {
    				printf("** TI ext2fs read block (indir 2 2)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir2_size = blksz;
    			ext4fs_indir2_blkno = -1;
    		}
    		if (blksz != ext4fs_indir2_size) {
    			free(ext4fs_indir2_block);
    			ext4fs_indir2_block = NULL;
    			ext4fs_indir2_size = 0;
    			ext4fs_indir2_blkno = -1;
    			ext4fs_indir2_block = zalloc(blksz);
    			if (ext4fs_indir2_block == NULL) {
    				printf("** TI ext2fs read block (indir 2 2)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir2_size = blksz;
    		}
    
    		if ((le32_to_cpu(ext4fs_indir1_block[rblock /
    
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    						       perblock_parent]) <<
    		     log2_blksz)
    		    != ext4fs_indir2_blkno) {
    
    			status = ext4fs_devread((lbaint_t)le32_to_cpu
    
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    						(ext4fs_indir1_block
    						 [rblock /
    						  perblock_parent]) <<
    						log2_blksz, 0, blksz,
    						(char *)ext4fs_indir2_block);
    			if (status == 0) {
    				printf("** TI ext2fs read block (indir 2 2)"
    					"failed. **\n");
    				return -1;
    			}
    			ext4fs_indir2_blkno =
    
    			    le32_to_cpu(ext4fs_indir1_block[rblock /
    
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    							      perblock_parent])
    			    << log2_blksz;
    		}
    
    		if (ext4fs_indir3_block == NULL) {
    			ext4fs_indir3_block = zalloc(blksz);
    			if (ext4fs_indir3_block == NULL) {
    				printf("** TI ext2fs read block (indir 2 2)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir3_size = blksz;
    			ext4fs_indir3_blkno = -1;
    		}
    		if (blksz != ext4fs_indir3_size) {
    			free(ext4fs_indir3_block);
    			ext4fs_indir3_block = NULL;
    			ext4fs_indir3_size = 0;
    			ext4fs_indir3_blkno = -1;
    			ext4fs_indir3_block = zalloc(blksz);
    			if (ext4fs_indir3_block == NULL) {
    				printf("** TI ext2fs read block (indir 2 2)"
    					"malloc failed. **\n");
    				return -1;
    			}
    			ext4fs_indir3_size = blksz;
    		}
    
    		if ((le32_to_cpu(ext4fs_indir2_block[rblock
    
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    						       /
    						       perblock_child]) <<
    		     log2_blksz) != ext4fs_indir3_blkno) {
    			status =
    
    			    ext4fs_devread((lbaint_t)le32_to_cpu
    
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    					   (ext4fs_indir2_block
    					    [(rblock / perblock_child)
    					     % (blksz / 4)]) << log2_blksz, 0,
    					   blksz, (char *)ext4fs_indir3_block);
    			if (status == 0) {
    				printf("** TI ext2fs read block (indir 2 2)"
    				       "failed. **\n");
    				return -1;
    			}
    			ext4fs_indir3_blkno =
    
    			    le32_to_cpu(ext4fs_indir2_block[(rblock /
    
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    							       perblock_child) %
    							      (blksz /
    							       4)]) <<
    			    log2_blksz;
    		}
    
    
    		blknr = le32_to_cpu(ext4fs_indir3_block
    
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    				      [rblock % perblock_child]);
    	}
    
    	debug("read_allocated_block %ld\n", blknr);
    
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    	return blknr;
    }
    
    
    /**
     * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
     *			    global pointers
     *
     * This function assures that for a file with the same name but different size
     * the sequential store on the ext4 filesystem will be correct.
     *
     * In this function the global data, responsible for internal representation
     * of the ext4 data are initialized to the reset state. Without this, during
     * replacement of the smaller file with the bigger truncation of new file was
     * performed.
     */
    void ext4fs_reinit_global(void)
    
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    {
    	if (ext4fs_indir1_block != NULL) {
    		free(ext4fs_indir1_block);
    		ext4fs_indir1_block = NULL;
    		ext4fs_indir1_size = 0;
    		ext4fs_indir1_blkno = -1;
    	}
    	if (ext4fs_indir2_block != NULL) {
    		free(ext4fs_indir2_block);
    		ext4fs_indir2_block = NULL;
    		ext4fs_indir2_size = 0;
    		ext4fs_indir2_blkno = -1;
    	}
    	if (ext4fs_indir3_block != NULL) {
    		free(ext4fs_indir3_block);
    		ext4fs_indir3_block = NULL;
    		ext4fs_indir3_size = 0;
    		ext4fs_indir3_blkno = -1;
    	}
    }
    
    void ext4fs_close(void)
    {
    	if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
    		ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
    		ext4fs_file = NULL;
    	}
    	if (ext4fs_root != NULL) {
    		free(ext4fs_root);
    		ext4fs_root = NULL;
    	}
    
    	ext4fs_reinit_global();
    }
    
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    int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
    				struct ext2fs_node **fnode, int *ftype)
    {
    	unsigned int fpos = 0;
    	int status;
    
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    	struct ext2fs_node *diro = (struct ext2fs_node *) dir;
    
    #ifdef DEBUG
    	if (name != NULL)
    		printf("Iterate dir %s\n", name);
    #endif /* of DEBUG */
    	if (!diro->inode_read) {
    		status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
    		if (status == 0)
    			return 0;
    	}
    	/* Search the file.  */
    
    	while (fpos < le32_to_cpu(diro->inode.size)) {
    
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    		struct ext2_dirent dirent;
    
    		status = ext4fs_read_file(diro, fpos,
    					   sizeof(struct ext2_dirent),
    
    					   (char *)&dirent, &actread);
    		if (status < 0)
    
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    			return 0;
    
    
    		if (dirent.direntlen == 0) {
    			printf("Failed to iterate over directory %s\n", name);
    			return 0;
    		}
    
    
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    		if (dirent.namelen != 0) {