438 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			438 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* vi: set sw=4 ts=4: */
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| /*
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|  * block.c --- iterate over all blocks in an inode
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|  *
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|  * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
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|  *
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|  * %Begin-Header%
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|  * This file may be redistributed under the terms of the GNU Public
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|  * License.
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|  * %End-Header%
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|  */
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| 
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| #include <stdio.h>
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| #include <string.h>
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| #if HAVE_UNISTD_H
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| #include <unistd.h>
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| #endif
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| 
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| #include "ext2_fs.h"
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| #include "ext2fs.h"
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| 
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| struct block_context {
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| 	ext2_filsys	fs;
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| 	int (*func)(ext2_filsys	fs,
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| 		    blk_t	*blocknr,
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| 		    e2_blkcnt_t	bcount,
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| 		    blk_t	ref_blk,
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| 		    int		ref_offset,
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| 		    void	*priv_data);
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| 	e2_blkcnt_t	bcount;
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| 	int		bsize;
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| 	int		flags;
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| 	errcode_t	errcode;
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| 	char	*ind_buf;
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| 	char	*dind_buf;
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| 	char	*tind_buf;
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| 	void	*priv_data;
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| };
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| 
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| static int block_iterate_ind(blk_t *ind_block, blk_t ref_block,
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| 			     int ref_offset, struct block_context *ctx)
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| {
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| 	int	ret = 0, changed = 0;
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| 	int	i, flags, limit, offset;
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| 	blk_t	*block_nr;
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| 
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| 	limit = ctx->fs->blocksize >> 2;
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| 	if (!(ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
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| 	    !(ctx->flags & BLOCK_FLAG_DATA_ONLY))
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| 		ret = (*ctx->func)(ctx->fs, ind_block,
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| 				   BLOCK_COUNT_IND, ref_block,
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| 				   ref_offset, ctx->priv_data);
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| 	if (!*ind_block || (ret & BLOCK_ABORT)) {
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| 		ctx->bcount += limit;
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| 		return ret;
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| 	}
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| 	if (*ind_block >= ctx->fs->super->s_blocks_count ||
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| 	    *ind_block < ctx->fs->super->s_first_data_block) {
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| 		ctx->errcode = EXT2_ET_BAD_IND_BLOCK;
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| 		ret |= BLOCK_ERROR;
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| 		return ret;
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| 	}
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| 	ctx->errcode = ext2fs_read_ind_block(ctx->fs, *ind_block,
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| 					     ctx->ind_buf);
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| 	if (ctx->errcode) {
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| 		ret |= BLOCK_ERROR;
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| 		return ret;
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| 	}
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| 
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| 	block_nr = (blk_t *) ctx->ind_buf;
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| 	offset = 0;
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| 	if (ctx->flags & BLOCK_FLAG_APPEND) {
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| 		for (i = 0; i < limit; i++, ctx->bcount++, block_nr++) {
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| 			flags = (*ctx->func)(ctx->fs, block_nr, ctx->bcount,
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| 					     *ind_block, offset,
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| 					     ctx->priv_data);
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| 			changed	|= flags;
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| 			if (flags & BLOCK_ABORT) {
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| 				ret |= BLOCK_ABORT;
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| 				break;
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| 			}
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| 			offset += sizeof(blk_t);
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| 		}
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| 	} else {
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| 		for (i = 0; i < limit; i++, ctx->bcount++, block_nr++) {
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| 			if (*block_nr == 0)
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| 				continue;
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| 			flags = (*ctx->func)(ctx->fs, block_nr, ctx->bcount,
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| 					     *ind_block, offset,
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| 					     ctx->priv_data);
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| 			changed	|= flags;
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| 			if (flags & BLOCK_ABORT) {
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| 				ret |= BLOCK_ABORT;
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| 				break;
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| 			}
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| 			offset += sizeof(blk_t);
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| 		}
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| 	}
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| 	if (changed & BLOCK_CHANGED) {
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| 		ctx->errcode = ext2fs_write_ind_block(ctx->fs, *ind_block,
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| 						      ctx->ind_buf);
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| 		if (ctx->errcode)
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| 			ret |= BLOCK_ERROR | BLOCK_ABORT;
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| 	}
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| 	if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
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| 	    !(ctx->flags & BLOCK_FLAG_DATA_ONLY) &&
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| 	    !(ret & BLOCK_ABORT))
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| 		ret |= (*ctx->func)(ctx->fs, ind_block,
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| 				    BLOCK_COUNT_IND, ref_block,
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| 				    ref_offset, ctx->priv_data);
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| 	return ret;
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| }
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| 
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| static int block_iterate_dind(blk_t *dind_block, blk_t ref_block,
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| 			      int ref_offset, struct block_context *ctx)
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| {
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| 	int	ret = 0, changed = 0;
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| 	int	i, flags, limit, offset;
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| 	blk_t	*block_nr;
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| 
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| 	limit = ctx->fs->blocksize >> 2;
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| 	if (!(ctx->flags & (BLOCK_FLAG_DEPTH_TRAVERSE |
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| 			    BLOCK_FLAG_DATA_ONLY)))
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| 		ret = (*ctx->func)(ctx->fs, dind_block,
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| 				   BLOCK_COUNT_DIND, ref_block,
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| 				   ref_offset, ctx->priv_data);
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| 	if (!*dind_block || (ret & BLOCK_ABORT)) {
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| 		ctx->bcount += limit*limit;
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| 		return ret;
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| 	}
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| 	if (*dind_block >= ctx->fs->super->s_blocks_count ||
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| 	    *dind_block < ctx->fs->super->s_first_data_block) {
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| 		ctx->errcode = EXT2_ET_BAD_DIND_BLOCK;
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| 		ret |= BLOCK_ERROR;
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| 		return ret;
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| 	}
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| 	ctx->errcode = ext2fs_read_ind_block(ctx->fs, *dind_block,
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| 					     ctx->dind_buf);
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| 	if (ctx->errcode) {
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| 		ret |= BLOCK_ERROR;
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| 		return ret;
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| 	}
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| 
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| 	block_nr = (blk_t *) ctx->dind_buf;
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| 	offset = 0;
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| 	if (ctx->flags & BLOCK_FLAG_APPEND) {
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| 		for (i = 0; i < limit; i++, block_nr++) {
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| 			flags = block_iterate_ind(block_nr,
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| 						  *dind_block, offset,
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| 						  ctx);
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| 			changed |= flags;
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| 			if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
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| 				ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
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| 				break;
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| 			}
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| 			offset += sizeof(blk_t);
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| 		}
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| 	} else {
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| 		for (i = 0; i < limit; i++, block_nr++) {
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| 			if (*block_nr == 0) {
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| 				ctx->bcount += limit;
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| 				continue;
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| 			}
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| 			flags = block_iterate_ind(block_nr,
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| 						  *dind_block, offset,
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| 						  ctx);
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| 			changed |= flags;
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| 			if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
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| 				ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
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| 				break;
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| 			}
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| 			offset += sizeof(blk_t);
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| 		}
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| 	}
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| 	if (changed & BLOCK_CHANGED) {
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| 		ctx->errcode = ext2fs_write_ind_block(ctx->fs, *dind_block,
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| 						      ctx->dind_buf);
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| 		if (ctx->errcode)
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| 			ret |= BLOCK_ERROR | BLOCK_ABORT;
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| 	}
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| 	if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
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| 	    !(ctx->flags & BLOCK_FLAG_DATA_ONLY) &&
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| 	    !(ret & BLOCK_ABORT))
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| 		ret |= (*ctx->func)(ctx->fs, dind_block,
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| 				    BLOCK_COUNT_DIND, ref_block,
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| 				    ref_offset, ctx->priv_data);
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| 	return ret;
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| }
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| 
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| static int block_iterate_tind(blk_t *tind_block, blk_t ref_block,
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| 			      int ref_offset, struct block_context *ctx)
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| {
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| 	int	ret = 0, changed = 0;
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| 	int	i, flags, limit, offset;
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| 	blk_t	*block_nr;
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| 
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| 	limit = ctx->fs->blocksize >> 2;
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| 	if (!(ctx->flags & (BLOCK_FLAG_DEPTH_TRAVERSE |
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| 			    BLOCK_FLAG_DATA_ONLY)))
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| 		ret = (*ctx->func)(ctx->fs, tind_block,
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| 				   BLOCK_COUNT_TIND, ref_block,
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| 				   ref_offset, ctx->priv_data);
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| 	if (!*tind_block || (ret & BLOCK_ABORT)) {
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| 		ctx->bcount += limit*limit*limit;
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| 		return ret;
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| 	}
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| 	if (*tind_block >= ctx->fs->super->s_blocks_count ||
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| 	    *tind_block < ctx->fs->super->s_first_data_block) {
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| 		ctx->errcode = EXT2_ET_BAD_TIND_BLOCK;
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| 		ret |= BLOCK_ERROR;
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| 		return ret;
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| 	}
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| 	ctx->errcode = ext2fs_read_ind_block(ctx->fs, *tind_block,
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| 					     ctx->tind_buf);
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| 	if (ctx->errcode) {
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| 		ret |= BLOCK_ERROR;
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| 		return ret;
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| 	}
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| 
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| 	block_nr = (blk_t *) ctx->tind_buf;
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| 	offset = 0;
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| 	if (ctx->flags & BLOCK_FLAG_APPEND) {
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| 		for (i = 0; i < limit; i++, block_nr++) {
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| 			flags = block_iterate_dind(block_nr,
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| 						   *tind_block,
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| 						   offset, ctx);
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| 			changed |= flags;
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| 			if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
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| 				ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
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| 				break;
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| 			}
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| 			offset += sizeof(blk_t);
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| 		}
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| 	} else {
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| 		for (i = 0; i < limit; i++, block_nr++) {
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| 			if (*block_nr == 0) {
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| 				ctx->bcount += limit*limit;
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| 				continue;
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| 			}
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| 			flags = block_iterate_dind(block_nr,
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| 						   *tind_block,
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| 						   offset, ctx);
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| 			changed |= flags;
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| 			if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
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| 				ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
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| 				break;
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| 			}
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| 			offset += sizeof(blk_t);
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| 		}
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| 	}
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| 	if (changed & BLOCK_CHANGED) {
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| 		ctx->errcode = ext2fs_write_ind_block(ctx->fs, *tind_block,
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| 						      ctx->tind_buf);
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| 		if (ctx->errcode)
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| 			ret |= BLOCK_ERROR | BLOCK_ABORT;
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| 	}
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| 	if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
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| 	    !(ctx->flags & BLOCK_FLAG_DATA_ONLY) &&
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| 	    !(ret & BLOCK_ABORT))
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| 		ret |= (*ctx->func)(ctx->fs, tind_block,
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| 				    BLOCK_COUNT_TIND, ref_block,
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| 				    ref_offset, ctx->priv_data);
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| 
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| 	return ret;
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| }
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| 
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| errcode_t ext2fs_block_iterate2(ext2_filsys fs,
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| 				ext2_ino_t ino,
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| 				int	flags,
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| 				char *block_buf,
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| 				int (*func)(ext2_filsys fs,
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| 					    blk_t	*blocknr,
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| 					    e2_blkcnt_t	blockcnt,
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| 					    blk_t	ref_blk,
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| 					    int		ref_offset,
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| 					    void	*priv_data),
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| 				void *priv_data)
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| {
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| 	int	i;
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| 	int	got_inode = 0;
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| 	int	ret = 0;
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| 	blk_t	blocks[EXT2_N_BLOCKS];	/* directory data blocks */
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| 	struct ext2_inode inode;
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| 	errcode_t	retval;
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| 	struct block_context ctx;
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| 	int	limit;
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| 
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| 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
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| 
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| 	/*
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| 	 * Check to see if we need to limit large files
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| 	 */
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| 	if (flags & BLOCK_FLAG_NO_LARGE) {
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| 		ctx.errcode = ext2fs_read_inode(fs, ino, &inode);
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| 		if (ctx.errcode)
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| 			return ctx.errcode;
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| 		got_inode = 1;
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| 		if (!LINUX_S_ISDIR(inode.i_mode) &&
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| 		    (inode.i_size_high != 0))
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| 			return EXT2_ET_FILE_TOO_BIG;
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| 	}
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| 
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| 	retval = ext2fs_get_blocks(fs, ino, blocks);
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| 	if (retval)
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| 		return retval;
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| 
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| 	limit = fs->blocksize >> 2;
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| 
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| 	ctx.fs = fs;
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| 	ctx.func = func;
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| 	ctx.priv_data = priv_data;
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| 	ctx.flags = flags;
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| 	ctx.bcount = 0;
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| 	if (block_buf) {
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| 		ctx.ind_buf = block_buf;
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| 	} else {
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| 		retval = ext2fs_get_mem(fs->blocksize * 3, &ctx.ind_buf);
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| 		if (retval)
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| 			return retval;
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| 	}
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| 	ctx.dind_buf = ctx.ind_buf + fs->blocksize;
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| 	ctx.tind_buf = ctx.dind_buf + fs->blocksize;
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| 
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| 	/*
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| 	 * Iterate over the HURD translator block (if present)
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| 	 */
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| 	if ((fs->super->s_creator_os == EXT2_OS_HURD) &&
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| 	    !(flags & BLOCK_FLAG_DATA_ONLY)) {
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| 		ctx.errcode = ext2fs_read_inode(fs, ino, &inode);
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| 		if (ctx.errcode)
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| 			goto abort_exit;
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| 		got_inode = 1;
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| 		if (inode.osd1.hurd1.h_i_translator) {
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| 			ret |= (*ctx.func)(fs,
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| 					   &inode.osd1.hurd1.h_i_translator,
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| 					   BLOCK_COUNT_TRANSLATOR,
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| 					   0, 0, priv_data);
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| 			if (ret & BLOCK_ABORT)
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| 				goto abort_exit;
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| 		}
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| 	}
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| 
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| 	/*
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| 	 * Iterate over normal data blocks
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| 	 */
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| 	for (i = 0; i < EXT2_NDIR_BLOCKS; i++, ctx.bcount++) {
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| 		if (blocks[i] || (flags & BLOCK_FLAG_APPEND)) {
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| 			ret |= (*ctx.func)(fs, &blocks[i],
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| 					    ctx.bcount, 0, i, priv_data);
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| 			if (ret & BLOCK_ABORT)
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| 				goto abort_exit;
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| 		}
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| 	}
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| 	if (*(blocks + EXT2_IND_BLOCK) || (flags & BLOCK_FLAG_APPEND)) {
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| 		ret |= block_iterate_ind(blocks + EXT2_IND_BLOCK,
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| 					 0, EXT2_IND_BLOCK, &ctx);
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| 		if (ret & BLOCK_ABORT)
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| 			goto abort_exit;
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| 	} else
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| 		ctx.bcount += limit;
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| 	if (*(blocks + EXT2_DIND_BLOCK) || (flags & BLOCK_FLAG_APPEND)) {
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| 		ret |= block_iterate_dind(blocks + EXT2_DIND_BLOCK,
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| 					  0, EXT2_DIND_BLOCK, &ctx);
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| 		if (ret & BLOCK_ABORT)
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| 			goto abort_exit;
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| 	} else
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| 		ctx.bcount += limit * limit;
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| 	if (*(blocks + EXT2_TIND_BLOCK) || (flags & BLOCK_FLAG_APPEND)) {
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| 		ret |= block_iterate_tind(blocks + EXT2_TIND_BLOCK,
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| 					  0, EXT2_TIND_BLOCK, &ctx);
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| 		if (ret & BLOCK_ABORT)
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| 			goto abort_exit;
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| 	}
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| 
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| abort_exit:
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| 	if (ret & BLOCK_CHANGED) {
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| 		if (!got_inode) {
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| 			retval = ext2fs_read_inode(fs, ino, &inode);
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| 			if (retval)
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| 				return retval;
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| 		}
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| 		for (i=0; i < EXT2_N_BLOCKS; i++)
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| 			inode.i_block[i] = blocks[i];
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| 		retval = ext2fs_write_inode(fs, ino, &inode);
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| 		if (retval)
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| 			return retval;
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| 	}
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| 
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| 	if (!block_buf)
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| 		ext2fs_free_mem(&ctx.ind_buf);
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| 
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| 	return (ret & BLOCK_ERROR) ? ctx.errcode : 0;
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| }
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| 
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| /*
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|  * Emulate the old ext2fs_block_iterate function!
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|  */
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| 
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| struct xlate {
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| 	int (*func)(ext2_filsys	fs,
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| 		    blk_t	*blocknr,
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| 		    int		bcount,
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| 		    void	*priv_data);
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| 	void *real_private;
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| };
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| 
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| #ifdef __TURBOC__
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| # pragma argsused
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| #endif
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| static int xlate_func(ext2_filsys fs, blk_t *blocknr, e2_blkcnt_t blockcnt,
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| 		      blk_t ref_block EXT2FS_ATTR((unused)),
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| 		      int ref_offset EXT2FS_ATTR((unused)),
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| 		      void *priv_data)
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| {
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| 	struct xlate *xl = (struct xlate *) priv_data;
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| 
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| 	return (*xl->func)(fs, blocknr, (int) blockcnt, xl->real_private);
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| }
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| 
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| errcode_t ext2fs_block_iterate(ext2_filsys fs,
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| 			       ext2_ino_t ino,
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| 			       int	flags,
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| 			       char *block_buf,
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| 			       int (*func)(ext2_filsys fs,
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| 					   blk_t	*blocknr,
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| 					   int	blockcnt,
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| 					   void	*priv_data),
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| 			       void *priv_data)
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| {
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| 	struct xlate xl;
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| 
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| 	xl.real_private = priv_data;
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| 	xl.func = func;
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| 
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| 	return ext2fs_block_iterate2(fs, ino, BLOCK_FLAG_NO_LARGE | flags,
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| 				     block_buf, xlate_func, &xl);
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| }
 |