diff options
| -rw-r--r-- | fs/xfs/xfs_log_recover.c | 271 |
1 files changed, 168 insertions, 103 deletions
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index 594f7e63b432..be5568839442 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -1109,27 +1109,10 @@ xlog_verify_head( bool tmp_wrapped; /* - * Search backwards through the log looking for the log record header - * block. This wraps all the way back around to the head so something is - * seriously wrong if we can't find it. - */ - found = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, bp, rhead_blk, - rhead, wrapped); - if (found < 0) - return found; - if (!found) { - xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__); - return -EIO; - } - - *tail_blk = BLOCK_LSN(be64_to_cpu((*rhead)->h_tail_lsn)); - - /* - * Now that we have a tail block, check the head of the log for torn - * writes. Search again until we hit the tail or the maximum number of - * log record I/Os that could have been in flight at one time. Use a - * temporary buffer so we don't trash the rhead/bp pointer from the - * call above. + * Check the head of the log for torn writes. Search backwards from the + * head until we hit the tail or the maximum number of log record I/Os + * that could have been in flight at one time. Use a temporary buffer so + * we don't trash the rhead/bp pointers from the caller. */ tmp_bp = xlog_get_bp(log, 1); if (!tmp_bp) @@ -1216,6 +1199,115 @@ xlog_verify_head( } /* + * Check whether the head of the log points to an unmount record. In other + * words, determine whether the log is clean. If so, update the in-core state + * appropriately. + */ +static int +xlog_check_unmount_rec( + struct xlog *log, + xfs_daddr_t *head_blk, + xfs_daddr_t *tail_blk, + struct xlog_rec_header *rhead, + xfs_daddr_t rhead_blk, + struct xfs_buf *bp, + bool *clean) +{ + struct xlog_op_header *op_head; + xfs_daddr_t umount_data_blk; + xfs_daddr_t after_umount_blk; + int hblks; + int error; + char *offset; + + *clean = false; + + /* + * Look for unmount record. If we find it, then we know there was a + * clean unmount. Since 'i' could be the last block in the physical + * log, we convert to a log block before comparing to the head_blk. + * + * Save the current tail lsn to use to pass to xlog_clear_stale_blocks() + * below. We won't want to clear the unmount record if there is one, so + * we pass the lsn of the unmount record rather than the block after it. + */ + if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) { + int h_size = be32_to_cpu(rhead->h_size); + int h_version = be32_to_cpu(rhead->h_version); + + if ((h_version & XLOG_VERSION_2) && + (h_size > XLOG_HEADER_CYCLE_SIZE)) { + hblks = h_size / XLOG_HEADER_CYCLE_SIZE; + if (h_size % XLOG_HEADER_CYCLE_SIZE) + hblks++; + } else { + hblks = 1; + } + } else { + hblks = 1; + } + after_umount_blk = rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len)); + after_umount_blk = do_mod(after_umount_blk, log->l_logBBsize); + if (*head_blk == after_umount_blk && + be32_to_cpu(rhead->h_num_logops) == 1) { + umount_data_blk = rhead_blk + hblks; + umount_data_blk = do_mod(umount_data_blk, log->l_logBBsize); + error = xlog_bread(log, umount_data_blk, 1, bp, &offset); + if (error) + return error; + + op_head = (struct xlog_op_header *)offset; + if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) { + /* + * Set tail and last sync so that newly written log + * records will point recovery to after the current + * unmount record. + */ + xlog_assign_atomic_lsn(&log->l_tail_lsn, + log->l_curr_cycle, after_umount_blk); + xlog_assign_atomic_lsn(&log->l_last_sync_lsn, + log->l_curr_cycle, after_umount_blk); + *tail_blk = after_umount_blk; + + *clean = true; + } + } + + return 0; +} + +static void +xlog_set_state( + struct xlog *log, + xfs_daddr_t head_blk, + struct xlog_rec_header *rhead, + xfs_daddr_t rhead_blk, + bool bump_cycle) +{ + /* + * Reset log values according to the state of the log when we + * crashed. In the case where head_blk == 0, we bump curr_cycle + * one because the next write starts a new cycle rather than + * continuing the cycle of the last good log record. At this + * point we have guaranteed that all partial log records have been + * accounted for. Therefore, we know that the last good log record + * written was complete and ended exactly on the end boundary + * of the physical log. + */ + log->l_prev_block = rhead_blk; + log->l_curr_block = (int)head_blk; + log->l_curr_cycle = be32_to_cpu(rhead->h_cycle); + if (bump_cycle) + log->l_curr_cycle++; + atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn)); + atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn)); + xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle, + BBTOB(log->l_curr_block)); + xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle, + BBTOB(log->l_curr_block)); +} + +/* * Find the sync block number or the tail of the log. * * This will be the block number of the last record to have its @@ -1238,22 +1330,20 @@ xlog_find_tail( xfs_daddr_t *tail_blk) { xlog_rec_header_t *rhead; - xlog_op_header_t *op_head; char *offset = NULL; xfs_buf_t *bp; int error; - xfs_daddr_t umount_data_blk; - xfs_daddr_t after_umount_blk; xfs_daddr_t rhead_blk; xfs_lsn_t tail_lsn; - int hblks; bool wrapped = false; + bool clean = false; /* * Find previous log record */ if ((error = xlog_find_head(log, head_blk))) return error; + ASSERT(*head_blk < INT_MAX); bp = xlog_get_bp(log, 1); if (!bp) @@ -1271,100 +1361,75 @@ xlog_find_tail( } /* - * Trim the head block back to skip over torn records. We can have - * multiple log I/Os in flight at any time, so we assume CRC failures - * back through the previous several records are torn writes and skip - * them. + * Search backwards through the log looking for the log record header + * block. This wraps all the way back around to the head so something is + * seriously wrong if we can't find it. */ - ASSERT(*head_blk < INT_MAX); - error = xlog_verify_head(log, head_blk, tail_blk, bp, &rhead_blk, - &rhead, &wrapped); - if (error) - goto done; + error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, bp, + &rhead_blk, &rhead, &wrapped); + if (error < 0) + return error; + if (!error) { + xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__); + return -EIO; + } + *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn)); /* - * Reset log values according to the state of the log when we - * crashed. In the case where head_blk == 0, we bump curr_cycle - * one because the next write starts a new cycle rather than - * continuing the cycle of the last good log record. At this - * point we have guaranteed that all partial log records have been - * accounted for. Therefore, we know that the last good log record - * written was complete and ended exactly on the end boundary - * of the physical log. + * Set the log state based on the current head record. */ - log->l_prev_block = rhead_blk; - log->l_curr_block = (int)*head_blk; - log->l_curr_cycle = be32_to_cpu(rhead->h_cycle); - if (wrapped) - log->l_curr_cycle++; - atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn)); - atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn)); - xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle, - BBTOB(log->l_curr_block)); - xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle, - BBTOB(log->l_curr_block)); + xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped); + tail_lsn = atomic64_read(&log->l_tail_lsn); /* - * Look for unmount record. If we find it, then we know there - * was a clean unmount. Since 'i' could be the last block in - * the physical log, we convert to a log block before comparing - * to the head_blk. + * Look for an unmount record at the head of the log. This sets the log + * state to determine whether recovery is necessary. + */ + error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead, + rhead_blk, bp, &clean); + if (error) + goto done; + + /* + * Verify the log head if the log is not clean (e.g., we have anything + * but an unmount record at the head). This uses CRC verification to + * detect and trim torn writes. If discovered, CRC failures are + * considered torn writes and the log head is trimmed accordingly. * - * Save the current tail lsn to use to pass to - * xlog_clear_stale_blocks() below. We won't want to clear the - * unmount record if there is one, so we pass the lsn of the - * unmount record rather than the block after it. + * Note that we can only run CRC verification when the log is dirty + * because there's no guarantee that the log data behind an unmount + * record is compatible with the current architecture. */ - if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) { - int h_size = be32_to_cpu(rhead->h_size); - int h_version = be32_to_cpu(rhead->h_version); + if (!clean) { + xfs_daddr_t orig_head = *head_blk; - if ((h_version & XLOG_VERSION_2) && - (h_size > XLOG_HEADER_CYCLE_SIZE)) { - hblks = h_size / XLOG_HEADER_CYCLE_SIZE; - if (h_size % XLOG_HEADER_CYCLE_SIZE) - hblks++; - } else { - hblks = 1; - } - } else { - hblks = 1; - } - after_umount_blk = rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len)); - after_umount_blk = do_mod(after_umount_blk, log->l_logBBsize); - tail_lsn = atomic64_read(&log->l_tail_lsn); - if (*head_blk == after_umount_blk && - be32_to_cpu(rhead->h_num_logops) == 1) { - umount_data_blk = rhead_blk + hblks; - umount_data_blk = do_mod(umount_data_blk, log->l_logBBsize); - error = xlog_bread(log, umount_data_blk, 1, bp, &offset); + error = xlog_verify_head(log, head_blk, tail_blk, bp, + &rhead_blk, &rhead, &wrapped); if (error) goto done; - op_head = (xlog_op_header_t *)offset; - if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) { - /* - * Set tail and last sync so that newly written - * log records will point recovery to after the - * current unmount record. - */ - xlog_assign_atomic_lsn(&log->l_tail_lsn, - log->l_curr_cycle, after_umount_blk); - xlog_assign_atomic_lsn(&log->l_last_sync_lsn, - log->l_curr_cycle, after_umount_blk); - *tail_blk = after_umount_blk; - - /* - * Note that the unmount was clean. If the unmount - * was not clean, we need to know this to rebuild the - * superblock counters from the perag headers if we - * have a filesystem using non-persistent counters. - */ - log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN; + /* update in-core state again if the head changed */ + if (*head_blk != orig_head) { + xlog_set_state(log, *head_blk, rhead, rhead_blk, + wrapped); + tail_lsn = atomic64_read(&log->l_tail_lsn); + error = xlog_check_unmount_rec(log, head_blk, tail_blk, + rhead, rhead_blk, bp, + &clean); + if (error) + goto done; } } /* + * Note that the unmount was clean. If the unmount was not clean, we + * need to know this to rebuild the superblock counters from the perag + * headers if we have a filesystem using non-persistent counters. + */ + if (clean) + log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN; + + /* * Make sure that there are no blocks in front of the head * with the same cycle number as the head. This can happen * because we allow multiple outstanding log writes concurrently, |