diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 08f806379b074..3c31f7f8aa654 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2901,91 +2901,163 @@ static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh, struct stripe_head_state *s, struct r6_state *r6s, int disks) { - int update_p = 0, update_q = 0; - struct r5dev *dev; int pd_idx = sh->pd_idx; int qd_idx = sh->qd_idx; - unsigned long cpu; - struct page *tmp_page; + struct r5dev *dev; set_bit(STRIPE_HANDLE, &sh->state); BUG_ON(s->failed > 2); - BUG_ON(s->uptodate < disks); + /* Want to check and possibly repair P and Q. * However there could be one 'failed' device, in which * case we can only check one of them, possibly using the * other to generate missing data */ - cpu = get_cpu(); - tmp_page = per_cpu_ptr(conf->percpu, cpu)->spare_page; - if (s->failed == r6s->q_failed) { - /* The only possible failed device holds 'Q', so it - * makes sense to check P (If anything else were failed, - * we would have used P to recreate it). - */ - compute_block_1(sh, pd_idx, 1); - if (!page_is_zero(sh->dev[pd_idx].page)) { - compute_block_1(sh, pd_idx, 0); - update_p = 1; + + switch (sh->check_state) { + case check_state_idle: + /* start a new check operation if there are < 2 failures */ + if (s->failed == r6s->q_failed) { + /* The only possible failed device holds Q, so it + * makes sense to check P (If anything else were failed, + * we would have used P to recreate it). + */ + sh->check_state = check_state_run; } - } - if (!r6s->q_failed && s->failed < 2) { - /* q is not failed, and we didn't use it to generate - * anything, so it makes sense to check it - */ - memcpy(page_address(tmp_page), - page_address(sh->dev[qd_idx].page), - STRIPE_SIZE); - compute_parity6(sh, UPDATE_PARITY); - if (memcmp(page_address(tmp_page), - page_address(sh->dev[qd_idx].page), - STRIPE_SIZE) != 0) { - clear_bit(STRIPE_INSYNC, &sh->state); - update_q = 1; + if (!r6s->q_failed && s->failed < 2) { + /* Q is not failed, and we didn't use it to generate + * anything, so it makes sense to check it + */ + if (sh->check_state == check_state_run) + sh->check_state = check_state_run_pq; + else + sh->check_state = check_state_run_q; } - } - put_cpu(); - if (update_p || update_q) { - conf->mddev->resync_mismatches += STRIPE_SECTORS; - if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) - /* don't try to repair!! */ - update_p = update_q = 0; - } + /* discard potentially stale zero_sum_result */ + sh->ops.zero_sum_result = 0; - /* now write out any block on a failed drive, - * or P or Q if they need it - */ + if (sh->check_state == check_state_run) { + /* async_xor_zero_sum destroys the contents of P */ + clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); + s->uptodate--; + } + if (sh->check_state >= check_state_run && + sh->check_state <= check_state_run_pq) { + /* async_syndrome_zero_sum preserves P and Q, so + * no need to mark them !uptodate here + */ + set_bit(STRIPE_OP_CHECK, &s->ops_request); + break; + } - if (s->failed == 2) { - dev = &sh->dev[r6s->failed_num[1]]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } - if (s->failed >= 1) { - dev = &sh->dev[r6s->failed_num[0]]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } + /* we have 2-disk failure */ + BUG_ON(s->failed != 2); + /* fall through */ + case check_state_compute_result: + sh->check_state = check_state_idle; - if (update_p) { - dev = &sh->dev[pd_idx]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } - if (update_q) { - dev = &sh->dev[qd_idx]; - s->locked++; - set_bit(R5_LOCKED, &dev->flags); - set_bit(R5_Wantwrite, &dev->flags); - } - clear_bit(STRIPE_DEGRADED, &sh->state); + /* check that a write has not made the stripe insync */ + if (test_bit(STRIPE_INSYNC, &sh->state)) + break; - set_bit(STRIPE_INSYNC, &sh->state); + /* now write out any block on a failed drive, + * or P or Q if they were recomputed + */ + BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */ + if (s->failed == 2) { + dev = &sh->dev[r6s->failed_num[1]]; + s->locked++; + set_bit(R5_LOCKED, &dev->flags); + set_bit(R5_Wantwrite, &dev->flags); + } + if (s->failed >= 1) { + dev = &sh->dev[r6s->failed_num[0]]; + s->locked++; + set_bit(R5_LOCKED, &dev->flags); + set_bit(R5_Wantwrite, &dev->flags); + } + if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) { + dev = &sh->dev[pd_idx]; + s->locked++; + set_bit(R5_LOCKED, &dev->flags); + set_bit(R5_Wantwrite, &dev->flags); + } + if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) { + dev = &sh->dev[qd_idx]; + s->locked++; + set_bit(R5_LOCKED, &dev->flags); + set_bit(R5_Wantwrite, &dev->flags); + } + clear_bit(STRIPE_DEGRADED, &sh->state); + + set_bit(STRIPE_INSYNC, &sh->state); + break; + case check_state_run: + case check_state_run_q: + case check_state_run_pq: + break; /* we will be called again upon completion */ + case check_state_check_result: + sh->check_state = check_state_idle; + + /* handle a successful check operation, if parity is correct + * we are done. Otherwise update the mismatch count and repair + * parity if !MD_RECOVERY_CHECK + */ + if (sh->ops.zero_sum_result == 0) { + /* both parities are correct */ + if (!s->failed) + set_bit(STRIPE_INSYNC, &sh->state); + else { + /* in contrast to the raid5 case we can validate + * parity, but still have a failure to write + * back + */ + sh->check_state = check_state_compute_result; + /* Returning at this point means that we may go + * off and bring p and/or q uptodate again so + * we make sure to check zero_sum_result again + * to verify if p or q need writeback + */ + } + } else { + conf->mddev->resync_mismatches += STRIPE_SECTORS; + if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) + /* don't try to repair!! */ + set_bit(STRIPE_INSYNC, &sh->state); + else { + int *target = &sh->ops.target; + + sh->ops.target = -1; + sh->ops.target2 = -1; + sh->check_state = check_state_compute_run; + set_bit(STRIPE_COMPUTE_RUN, &sh->state); + set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); + if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) { + set_bit(R5_Wantcompute, + &sh->dev[pd_idx].flags); + *target = pd_idx; + target = &sh->ops.target2; + s->uptodate++; + } + if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) { + set_bit(R5_Wantcompute, + &sh->dev[qd_idx].flags); + *target = qd_idx; + s->uptodate++; + } + } + } + break; + case check_state_compute_run: + break; + default: + printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n", + __func__, sh->check_state, + (unsigned long long) sh->sector); + BUG(); + } } static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh,