diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/xfs/xfs_log_recover.c | 31 |
1 files changed, 15 insertions, 16 deletions
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index 7b3375db6728..3bfff4220a74 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -167,7 +167,6 @@ xlog_bread_noalign( ASSERT(nbblks > 0); ASSERT(BBTOB(nbblks) <= XFS_BUF_SIZE(bp)); - ASSERT(bp); XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no); XFS_BUF_READ(bp); @@ -380,14 +379,12 @@ xlog_find_cycle_start( } /* - * Check that the range of blocks does not contain the cycle number - * given. The scan needs to occur from front to back and the ptr into the - * region must be updated since a later routine will need to perform another - * test. If the region is completely good, we end up returning the same - * last block number. - * - * Set blkno to -1 if we encounter no errors. This is an invalid block number - * since we don't ever expect logs to get this large. + * Check that a range of blocks does not contain stop_on_cycle_no. + * Fill in *new_blk with the block offset where such a block is + * found, or with -1 (an invalid block number) if there is no such + * block in the range. The scan needs to occur from front to back + * and the pointer into the region must be updated since a later + * routine will need to perform another test. */ STATIC int xlog_find_verify_cycle( @@ -661,7 +658,7 @@ xlog_find_head( * In this case we want to find the first block with cycle * number matching last_half_cycle. We expect the log to be * some variation on - * x + 1 ... | x ... + * x + 1 ... | x ... | x * The first block with cycle number x (last_half_cycle) will * be where the new head belongs. First we do a binary search * for the first occurrence of last_half_cycle. The binary @@ -671,11 +668,13 @@ xlog_find_head( * the log, then we look for occurrences of last_half_cycle - 1 * at the end of the log. The cases we're looking for look * like - * x + 1 ... | x | x + 1 | x ... - * ^ binary search stopped here + * v binary search stopped here + * x + 1 ... | x | x + 1 | x ... | x + * ^ but we want to locate this spot * or - * x + 1 ... | x ... | x - 1 | x * <---------> less than scan distance + * x + 1 ... | x ... | x - 1 | x + * ^ we want to locate this spot */ stop_on_cycle = last_half_cycle; if ((error = xlog_find_cycle_start(log, bp, first_blk, @@ -731,9 +730,9 @@ xlog_find_head( * certainly not the head of the log. By searching for * last_half_cycle-1 we accomplish that. */ - start_blk = log_bbnum - num_scan_bblks + head_blk; ASSERT(head_blk <= INT_MAX && - (xfs_daddr_t) num_scan_bblks - head_blk >= 0); + (xfs_daddr_t) num_scan_bblks >= head_blk); + start_blk = log_bbnum - (num_scan_bblks - head_blk); if ((error = xlog_find_verify_cycle(log, start_blk, num_scan_bblks - (int)head_blk, (stop_on_cycle - 1), &new_blk))) @@ -780,7 +779,7 @@ validate_head: if ((error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0)) == -1) { /* We hit the beginning of the log during our search */ - start_blk = log_bbnum - num_scan_bblks + head_blk; + start_blk = log_bbnum - (num_scan_bblks - head_blk); new_blk = log_bbnum; ASSERT(start_blk <= INT_MAX && (xfs_daddr_t) log_bbnum-start_blk >= 0); |