diff options
Diffstat (limited to 'fs/befs/datastream.c')
| -rw-r--r-- | fs/befs/datastream.c | 381 |
1 files changed, 190 insertions, 191 deletions
diff --git a/fs/befs/datastream.c b/fs/befs/datastream.c index 59096b5e0fc7..97719a7c7e40 100644 --- a/fs/befs/datastream.c +++ b/fs/befs/datastream.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/befs/datastream.c * @@ -21,23 +22,23 @@ const befs_inode_addr BAD_IADDR = { 0, 0, 0 }; static int befs_find_brun_direct(struct super_block *sb, - befs_data_stream * data, - befs_blocknr_t blockno, befs_block_run * run); + const befs_data_stream *data, + befs_blocknr_t blockno, befs_block_run *run); static int befs_find_brun_indirect(struct super_block *sb, - befs_data_stream * data, + const befs_data_stream *data, befs_blocknr_t blockno, - befs_block_run * run); + befs_block_run *run); static int befs_find_brun_dblindirect(struct super_block *sb, - befs_data_stream * data, + const befs_data_stream *data, befs_blocknr_t blockno, - befs_block_run * run); + befs_block_run *run); /** * befs_read_datastream - get buffer_head containing data, starting from pos. * @sb: Filesystem superblock - * @ds: datastrem to find data with + * @ds: datastream to find data with * @pos: start of data * @off: offset of data in buffer_head->b_data * @@ -45,51 +46,54 @@ static int befs_find_brun_dblindirect(struct super_block *sb, * if you don't need to know offset just set @off = NULL. */ struct buffer_head * -befs_read_datastream(struct super_block *sb, befs_data_stream * ds, - befs_off_t pos, uint * off) +befs_read_datastream(struct super_block *sb, const befs_data_stream *ds, + befs_off_t pos, uint *off) { - struct buffer_head *bh = NULL; + struct buffer_head *bh; befs_block_run run; befs_blocknr_t block; /* block coresponding to pos */ - befs_debug(sb, "---> befs_read_datastream() %Lu", pos); + befs_debug(sb, "---> %s %llu", __func__, pos); block = pos >> BEFS_SB(sb)->block_shift; if (off) *off = pos - (block << BEFS_SB(sb)->block_shift); if (befs_fblock2brun(sb, ds, block, &run) != BEFS_OK) { befs_error(sb, "BeFS: Error finding disk addr of block %lu", - block); - befs_debug(sb, "<--- befs_read_datastream() ERROR"); + (unsigned long)block); + befs_debug(sb, "<--- %s ERROR", __func__); return NULL; } bh = befs_bread_iaddr(sb, run); if (!bh) { befs_error(sb, "BeFS: Error reading block %lu from datastream", - block); + (unsigned long)block); return NULL; } - befs_debug(sb, "<--- befs_read_datastream() read data, starting at %Lu", - pos); + befs_debug(sb, "<--- %s read data, starting at %llu", __func__, pos); return bh; } -/* +/** + * befs_fblock2brun - give back block run for fblock + * @sb: the superblock + * @data: datastream to read from + * @fblock: the blocknumber with the file position to find + * @run: The found run is passed back through this pointer + * * Takes a file position and gives back a brun who's starting block * is block number fblock of the file. - * + * * Returns BEFS_OK or BEFS_ERR. - * + * * Calls specialized functions for each of the three possible * datastream regions. - * - * 2001-11-15 Will Dyson */ int -befs_fblock2brun(struct super_block *sb, befs_data_stream * data, - befs_blocknr_t fblock, befs_block_run * run) +befs_fblock2brun(struct super_block *sb, const befs_data_stream *data, + befs_blocknr_t fblock, befs_block_run *run) { int err; befs_off_t pos = fblock << BEFS_SB(sb)->block_shift; @@ -106,7 +110,8 @@ befs_fblock2brun(struct super_block *sb, befs_data_stream * data, } else { befs_error(sb, "befs_fblock2brun() was asked to find block %lu, " - "which is not mapped by the datastream\n", fblock); + "which is not mapped by the datastream\n", + (unsigned long)fblock); err = BEFS_ERR; } return err; @@ -114,28 +119,29 @@ befs_fblock2brun(struct super_block *sb, befs_data_stream * data, /** * befs_read_lsmylink - read long symlink from datastream. - * @sb: Filesystem superblock - * @ds: Datastrem to read from - * @buf: Buffer in which to place long symlink data + * @sb: Filesystem superblock + * @ds: Datastream to read from + * @buff: Buffer in which to place long symlink data * @len: Length of the long symlink in bytes * * Returns the number of bytes read */ size_t -befs_read_lsymlink(struct super_block * sb, befs_data_stream * ds, void *buff, - befs_off_t len) +befs_read_lsymlink(struct super_block *sb, const befs_data_stream *ds, + void *buff, befs_off_t len) { befs_off_t bytes_read = 0; /* bytes readed */ u16 plen; - struct buffer_head *bh = NULL; - befs_debug(sb, "---> befs_read_lsymlink() length: %Lu", len); + struct buffer_head *bh; + + befs_debug(sb, "---> %s length: %llu", __func__, len); while (bytes_read < len) { bh = befs_read_datastream(sb, ds, bytes_read, NULL); if (!bh) { befs_error(sb, "BeFS: Error reading datastream block " - "starting from %Lu", bytes_read); - befs_debug(sb, "<--- befs_read_lsymlink() ERROR"); + "starting from %llu", bytes_read); + befs_debug(sb, "<--- %s ERROR", __func__); return bytes_read; } @@ -146,7 +152,8 @@ befs_read_lsymlink(struct super_block * sb, befs_data_stream * ds, void *buff, bytes_read += plen; } - befs_debug(sb, "<--- befs_read_lsymlink() read %u bytes", bytes_read); + befs_debug(sb, "<--- %s read %u bytes", __func__, (unsigned int) + bytes_read); return bytes_read; } @@ -162,14 +169,14 @@ befs_read_lsymlink(struct super_block * sb, befs_data_stream * ds, void *buff, */ befs_blocknr_t -befs_count_blocks(struct super_block * sb, befs_data_stream * ds) +befs_count_blocks(struct super_block *sb, const befs_data_stream *ds) { befs_blocknr_t blocks; befs_blocknr_t datablocks; /* File data blocks */ befs_blocknr_t metablocks; /* FS metadata blocks */ - befs_sb_info *befs_sb = BEFS_SB(sb); + struct befs_sb_info *befs_sb = BEFS_SB(sb); - befs_debug(sb, "---> befs_count_blocks()"); + befs_debug(sb, "---> %s", __func__); datablocks = ds->size >> befs_sb->block_shift; if (ds->size & (befs_sb->block_size - 1)) @@ -182,13 +189,13 @@ befs_count_blocks(struct super_block * sb, befs_data_stream * ds) metablocks += ds->indirect.len; /* - Double indir block, plus all the indirect blocks it mapps - In the double-indirect range, all block runs of data are - BEFS_DBLINDIR_BRUN_LEN blocks long. Therefore, we know - how many data block runs are in the double-indirect region, - and from that we know how many indirect blocks it takes to - map them. We assume that the indirect blocks are also - BEFS_DBLINDIR_BRUN_LEN blocks long. + * Double indir block, plus all the indirect blocks it maps. + * In the double-indirect range, all block runs of data are + * BEFS_DBLINDIR_BRUN_LEN blocks long. Therefore, we know + * how many data block runs are in the double-indirect region, + * and from that we know how many indirect blocks it takes to + * map them. We assume that the indirect blocks are also + * BEFS_DBLINDIR_BRUN_LEN blocks long. */ if (ds->size > ds->max_indirect_range && ds->max_indirect_range != 0) { uint dbl_bytes; @@ -206,104 +213,99 @@ befs_count_blocks(struct super_block * sb, befs_data_stream * ds) } blocks = datablocks + metablocks; - befs_debug(sb, "<--- befs_count_blocks() %u blocks", blocks); + befs_debug(sb, "<--- %s %u blocks", __func__, (unsigned int)blocks); return blocks; } -/* - Finds the block run that starts at file block number blockno - in the file represented by the datastream data, if that - blockno is in the direct region of the datastream. - - sb: the superblock - data: the datastream - blockno: the blocknumber to find - run: The found run is passed back through this pointer - - Return value is BEFS_OK if the blockrun is found, BEFS_ERR - otherwise. - - Algorithm: - Linear search. Checks each element of array[] to see if it - contains the blockno-th filesystem block. This is necessary - because the block runs map variable amounts of data. Simply - keeps a count of the number of blocks searched so far (sum), - incrementing this by the length of each block run as we come - across it. Adds sum to *count before returning (this is so - you can search multiple arrays that are logicaly one array, - as in the indirect region code). - - When/if blockno is found, if blockno is inside of a block - run as stored on disk, we offset the start and length members - of the block run, so that blockno is the start and len is - still valid (the run ends in the same place). - - 2001-11-15 Will Dyson -*/ +/** + * befs_find_brun_direct - find a direct block run in the datastream + * @sb: the superblock + * @data: the datastream + * @blockno: the blocknumber to find + * @run: The found run is passed back through this pointer + * + * Finds the block run that starts at file block number blockno + * in the file represented by the datastream data, if that + * blockno is in the direct region of the datastream. + * + * Return value is BEFS_OK if the blockrun is found, BEFS_ERR + * otherwise. + * + * Algorithm: + * Linear search. Checks each element of array[] to see if it + * contains the blockno-th filesystem block. This is necessary + * because the block runs map variable amounts of data. Simply + * keeps a count of the number of blocks searched so far (sum), + * incrementing this by the length of each block run as we come + * across it. Adds sum to *count before returning (this is so + * you can search multiple arrays that are logicaly one array, + * as in the indirect region code). + * + * When/if blockno is found, if blockno is inside of a block + * run as stored on disk, we offset the start and length members + * of the block run, so that blockno is the start and len is + * still valid (the run ends in the same place). + */ static int -befs_find_brun_direct(struct super_block *sb, befs_data_stream * data, - befs_blocknr_t blockno, befs_block_run * run) +befs_find_brun_direct(struct super_block *sb, const befs_data_stream *data, + befs_blocknr_t blockno, befs_block_run *run) { int i; - befs_block_run *array = data->direct; + const befs_block_run *array = data->direct; befs_blocknr_t sum; - befs_blocknr_t max_block = - data->max_direct_range >> BEFS_SB(sb)->block_shift; - - befs_debug(sb, "---> befs_find_brun_direct(), find %lu", blockno); - if (blockno > max_block) { - befs_error(sb, "befs_find_brun_direct() passed block outside of" - "direct region"); - return BEFS_ERR; - } + befs_debug(sb, "---> %s, find %lu", __func__, (unsigned long)blockno); for (i = 0, sum = 0; i < BEFS_NUM_DIRECT_BLOCKS; sum += array[i].len, i++) { if (blockno >= sum && blockno < sum + (array[i].len)) { int offset = blockno - sum; + run->allocation_group = array[i].allocation_group; run->start = array[i].start + offset; run->len = array[i].len - offset; - befs_debug(sb, "---> befs_find_brun_direct(), " - "found %lu at direct[%d]", blockno, i); + befs_debug(sb, "---> %s, " + "found %lu at direct[%d]", __func__, + (unsigned long)blockno, i); return BEFS_OK; } } - befs_debug(sb, "---> befs_find_brun_direct() ERROR"); + befs_error(sb, "%s failed to find file block %lu", __func__, + (unsigned long)blockno); + befs_debug(sb, "---> %s ERROR", __func__); return BEFS_ERR; } -/* - Finds the block run that starts at file block number blockno - in the file represented by the datastream data, if that - blockno is in the indirect region of the datastream. - - sb: the superblock - data: the datastream - blockno: the blocknumber to find - run: The found run is passed back through this pointer - - Return value is BEFS_OK if the blockrun is found, BEFS_ERR - otherwise. - - Algorithm: - For each block in the indirect run of the datastream, read - it in and search through it for search_blk. - - XXX: - Really should check to make sure blockno is inside indirect - region. - - 2001-11-15 Will Dyson -*/ +/** + * befs_find_brun_indirect - find a block run in the datastream + * @sb: the superblock + * @data: the datastream + * @blockno: the blocknumber to find + * @run: The found run is passed back through this pointer + * + * Finds the block run that starts at file block number blockno + * in the file represented by the datastream data, if that + * blockno is in the indirect region of the datastream. + * + * Return value is BEFS_OK if the blockrun is found, BEFS_ERR + * otherwise. + * + * Algorithm: + * For each block in the indirect run of the datastream, read + * it in and search through it for search_blk. + * + * XXX: + * Really should check to make sure blockno is inside indirect + * region. + */ static int befs_find_brun_indirect(struct super_block *sb, - befs_data_stream * data, befs_blocknr_t blockno, - befs_block_run * run) + const befs_data_stream *data, + befs_blocknr_t blockno, + befs_block_run *run) { int i, j; befs_blocknr_t sum = 0; @@ -316,19 +318,19 @@ befs_find_brun_indirect(struct super_block *sb, befs_blocknr_t indirblockno = iaddr2blockno(sb, &indirect); int arraylen = befs_iaddrs_per_block(sb); - befs_debug(sb, "---> befs_find_brun_indirect(), find %lu", blockno); + befs_debug(sb, "---> %s, find %lu", __func__, (unsigned long)blockno); indir_start_blk = data->max_direct_range >> BEFS_SB(sb)->block_shift; search_blk = blockno - indir_start_blk; /* Examine blocks of the indirect run one at a time */ for (i = 0; i < indirect.len; i++) { - indirblock = befs_bread(sb, indirblockno + i); + indirblock = sb_bread(sb, indirblockno + i); if (indirblock == NULL) { - befs_debug(sb, - "---> befs_find_brun_indirect() failed to " - "read disk block %lu from the indirect brun", - indirblockno + i); + befs_error(sb, "---> %s failed to read " + "disk block %lu from the indirect brun", + __func__, (unsigned long)indirblockno + i); + befs_debug(sb, "<--- %s ERROR", __func__); return BEFS_ERR; } @@ -348,9 +350,10 @@ befs_find_brun_indirect(struct super_block *sb, brelse(indirblock); befs_debug(sb, - "<--- befs_find_brun_indirect() found " - "file block %lu at indirect[%d]", - blockno, j + (i * arraylen)); + "<--- %s found file block " + "%lu at indirect[%d]", __func__, + (unsigned long)blockno, + j + (i * arraylen)); return BEFS_OK; } sum += len; @@ -360,58 +363,58 @@ befs_find_brun_indirect(struct super_block *sb, } /* Only fallthrough is an error */ - befs_error(sb, "BeFS: befs_find_brun_indirect() failed to find " - "file block %lu", blockno); + befs_error(sb, "BeFS: %s failed to find " + "file block %lu", __func__, (unsigned long)blockno); - befs_debug(sb, "<--- befs_find_brun_indirect() ERROR"); + befs_debug(sb, "<--- %s ERROR", __func__); return BEFS_ERR; } -/* - Finds the block run that starts at file block number blockno - in the file represented by the datastream data, if that - blockno is in the double-indirect region of the datastream. - - sb: the superblock - data: the datastream - blockno: the blocknumber to find - run: The found run is passed back through this pointer - - Return value is BEFS_OK if the blockrun is found, BEFS_ERR - otherwise. - - Algorithm: - The block runs in the double-indirect region are different. - They are always allocated 4 fs blocks at a time, so each - block run maps a constant amount of file data. This means - that we can directly calculate how many block runs into the - double-indirect region we need to go to get to the one that - maps a particular filesystem block. - - We do this in two stages. First we calculate which of the - inode addresses in the double-indirect block will point us - to the indirect block that contains the mapping for the data, - then we calculate which of the inode addresses in that - indirect block maps the data block we are after. - - Oh, and once we've done that, we actually read in the blocks - that contain the inode addresses we calculated above. Even - though the double-indirect run may be several blocks long, - we can calculate which of those blocks will contain the index - we are after and only read that one. We then follow it to - the indirect block and perform a similar process to find - the actual block run that maps the data block we are interested - in. - - Then we offset the run as in befs_find_brun_array() and we are - done. - - 2001-11-15 Will Dyson -*/ +/** + * befs_find_brun_dblindirect - find a block run in the datastream + * @sb: the superblock + * @data: the datastream + * @blockno: the blocknumber to find + * @run: The found run is passed back through this pointer + * + * Finds the block run that starts at file block number blockno + * in the file represented by the datastream data, if that + * blockno is in the double-indirect region of the datastream. + * + * Return value is BEFS_OK if the blockrun is found, BEFS_ERR + * otherwise. + * + * Algorithm: + * The block runs in the double-indirect region are different. + * They are always allocated 4 fs blocks at a time, so each + * block run maps a constant amount of file data. This means + * that we can directly calculate how many block runs into the + * double-indirect region we need to go to get to the one that + * maps a particular filesystem block. + * + * We do this in two stages. First we calculate which of the + * inode addresses in the double-indirect block will point us + * to the indirect block that contains the mapping for the data, + * then we calculate which of the inode addresses in that + * indirect block maps the data block we are after. + * + * Oh, and once we've done that, we actually read in the blocks + * that contain the inode addresses we calculated above. Even + * though the double-indirect run may be several blocks long, + * we can calculate which of those blocks will contain the index + * we are after and only read that one. We then follow it to + * the indirect block and perform a similar process to find + * the actual block run that maps the data block we are interested + * in. + * + * Then we offset the run as in befs_find_brun_array() and we are + * done. + */ static int befs_find_brun_dblindirect(struct super_block *sb, - befs_data_stream * data, befs_blocknr_t blockno, - befs_block_run * run) + const befs_data_stream *data, + befs_blocknr_t blockno, + befs_block_run *run) { int dblindir_indx; int indir_indx; @@ -425,11 +428,10 @@ befs_find_brun_dblindirect(struct super_block *sb, struct buffer_head *dbl_indir_block; struct buffer_head *indir_block; befs_block_run indir_run; - befs_disk_inode_addr *iaddr_array = NULL; - befs_sb_info *befs_sb = BEFS_SB(sb); + befs_disk_inode_addr *iaddr_array; befs_blocknr_t indir_start_blk = - data->max_indirect_range >> befs_sb->block_shift; + data->max_indirect_range >> BEFS_SB(sb)->block_shift; off_t dbl_indir_off = blockno - indir_start_blk; @@ -444,7 +446,7 @@ befs_find_brun_dblindirect(struct super_block *sb, size_t diblklen = iblklen * befs_iaddrs_per_block(sb) * BEFS_DBLINDIR_BRUN_LEN; - befs_debug(sb, "---> befs_find_brun_dblindirect() find %lu", blockno); + befs_debug(sb, "---> %s find %lu", __func__, (unsigned long)blockno); /* First, discover which of the double_indir->indir blocks * contains pos. Then figure out how much of pos that @@ -460,21 +462,21 @@ befs_find_brun_dblindirect(struct super_block *sb, dbl_which_block = dblindir_indx / befs_iaddrs_per_block(sb); if (dbl_which_block > data->double_indirect.len) { befs_error(sb, "The double-indirect index calculated by " - "befs_read_brun_dblindirect(), %d, is outside the range " - "of the double-indirect block", dblindir_indx); + "%s, %d, is outside the range " + "of the double-indirect block", __func__, + dblindir_indx); return BEFS_ERR; } dbl_indir_block = - befs_bread(sb, iaddr2blockno(sb, &data->double_indirect) + + sb_bread(sb, iaddr2blockno(sb, &data->double_indirect) + dbl_which_block); if (dbl_indir_block == NULL) { - befs_error(sb, "befs_read_brun_dblindirect() couldn't read the " - "double-indirect block at blockno %lu", - iaddr2blockno(sb, - &data->double_indirect) + + befs_error(sb, "%s couldn't read the " + "double-indirect block at blockno %lu", __func__, + (unsigned long) + iaddr2blockno(sb, &data->double_indirect) + dbl_which_block); - brelse(dbl_indir_block); return BEFS_ERR; } @@ -483,24 +485,22 @@ befs_find_brun_dblindirect(struct super_block *sb, iaddr_array = (befs_disk_inode_addr *) dbl_indir_block->b_data; indir_run = fsrun_to_cpu(sb, iaddr_array[dbl_block_indx]); brelse(dbl_indir_block); - iaddr_array = NULL; /* Read indirect block */ which_block = indir_indx / befs_iaddrs_per_block(sb); if (which_block > indir_run.len) { befs_error(sb, "The indirect index calculated by " - "befs_read_brun_dblindirect(), %d, is outside the range " - "of the indirect block", indir_indx); + "%s, %d, is outside the range " + "of the indirect block", __func__, indir_indx); return BEFS_ERR; } indir_block = - befs_bread(sb, iaddr2blockno(sb, &indir_run) + which_block); + sb_bread(sb, iaddr2blockno(sb, &indir_run) + which_block); if (indir_block == NULL) { - befs_error(sb, "befs_read_brun_dblindirect() couldn't read the " - "indirect block at blockno %lu", + befs_error(sb, "%s couldn't read the indirect block " + "at blockno %lu", __func__, (unsigned long) iaddr2blockno(sb, &indir_run) + which_block); - brelse(indir_block); return BEFS_ERR; } @@ -508,7 +508,6 @@ befs_find_brun_dblindirect(struct super_block *sb, iaddr_array = (befs_disk_inode_addr *) indir_block->b_data; *run = fsrun_to_cpu(sb, iaddr_array[block_indx]); brelse(indir_block); - iaddr_array = NULL; blockno_at_run_start = indir_start_blk; blockno_at_run_start += diblklen * dblindir_indx; @@ -519,7 +518,7 @@ befs_find_brun_dblindirect(struct super_block *sb, run->len -= offset; befs_debug(sb, "Found file block %lu in double_indirect[%d][%d]," - " double_indirect_leftover = %lu", + " double_indirect_leftover = %lu", (unsigned long) blockno, dblindir_indx, indir_indx, dblindir_leftover); return BEFS_OK; |