fs/befs/datastream.c

54 	befs_blocknr_t block;	/* block coresponding to pos */
57 	block = pos >> BEFS_SB(sb)->block_shift;
59 		*off = pos - (block << BEFS_SB(sb)->block_shift);
61 	if (befs_fblock2brun(sb, ds, block, &run) != BEFS_OK) {
62 		befs_error(sb, "BeFS: Error finding disk addr of block %lu",
63 			   (unsigned long)block);
69 		befs_error(sb, "BeFS: Error reading block %lu from datastream",
70 			   (unsigned long)block);
80  * befs_fblock2brun - give back block run for fblock
86  * Takes a file position and gives back a brun who's starting block
87  * is block number fblock of the file.
112 			   "befs_fblock2brun() was asked to find block %lu, "
142 			befs_error(sb, "BeFS: Error reading datastream block "
185 	metablocks = 1;		/* Start with 1 block for inode */
187 	/* Size of indirect block */
192 	 * Double indir block, plus all the indirect blocks it maps.
193 	 * In the double-indirect range, all block runs of data are
195 	 * how many data block runs are in the double-indirect region,
222  * befs_find_brun_direct - find a direct block run in the datastream
228  * Finds the block run that starts at file block number blockno
237  * contains the blockno-th filesystem block. This is necessary
238  * because the block runs map variable amounts of data. Simply
240  * incrementing this by the length of each block run as we come
245  * When/if blockno is found, if blockno is inside of a block
247  * of the block run, so that blockno is the start and len is
276 	befs_error(sb, "%s failed to find file block %lu", __func__,
283  * befs_find_brun_indirect - find a block run in the datastream
289  * Finds the block run that starts at file block number blockno
297  * For each block in the indirect run of the datastream, read
331 				   "disk block %lu from the indirect brun",
353 					   "<--- %s found file block "
367 		   "file block %lu", __func__, (unsigned long)blockno);
374  * befs_find_brun_dblindirect - find a block run in the datastream
380  * Finds the block run that starts at file block number blockno
388  * The block runs in the double-indirect region are different.
390  * block run maps a constant amount of file data. This means
391  * that we can directly calculate how many block runs into the
393  * maps a particular filesystem block.
396  * inode addresses in the double-indirect block will point us
397  * to the indirect block that contains the mapping for the data,
399  * indirect block maps the data block we are after.
406  * the indirect block and perform a similar process to find
407  * the actual block run that maps the data block we are interested
439 	 * the indirect block pointed to by the double indirect block
444 	 * the double indirect block
454 	 * the indirect block contains pos.
461 	/* Read double indirect block */
466 			   "of the double-indirect block", __func__,
476 			   "double-indirect block at blockno %lu", __func__,
489 	/* Read indirect block */
494 			   "of the indirect block", __func__, indir_indx);
501 		befs_error(sb, "%s couldn't read the indirect block "
520 	befs_debug(sb, "Found file block %lu in double_indirect[%d][%d],"