diff options
| -rw-r--r-- | drivers/md/raid5.c | 58 | ||||
| -rw-r--r-- | drivers/md/raid5.h | 1 |
2 files changed, 41 insertions, 18 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index c1d94ed9718b..edbc80c4d346 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -136,6 +136,10 @@ static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt) /* Find first data disk in a raid6 stripe */ static inline int raid6_d0(struct stripe_head *sh) { + if (sh->ddf_layout) + /* ddf always start from first device */ + return 0; + /* md starts just after Q block */ if (sh->qd_idx == sh->disks - 1) return 0; else @@ -152,13 +156,15 @@ static inline int raid6_next_disk(int disk, int raid_disks) * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk * is raid_disks-1. This help does that mapping. */ -static int raid6_idx_to_slot(int idx, struct stripe_head *sh, int *count) +static int raid6_idx_to_slot(int idx, struct stripe_head *sh, + int *count, int syndrome_disks) { int slot; + if (idx == sh->pd_idx) - return sh->disks - 2; + return syndrome_disks; if (idx == sh->qd_idx) - return sh->disks - 1; + return syndrome_disks + 1; slot = (*count)++; return slot; } @@ -1267,6 +1273,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, unsigned long chunk_number; unsigned int chunk_offset; int pd_idx, qd_idx; + int ddf_layout = 0; sector_t new_sector; int sectors_per_chunk = conf->chunk_size >> 9; int raid_disks = previous ? conf->previous_raid_disks @@ -1386,6 +1393,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, qd_idx = 0; } else if (*dd_idx >= pd_idx) (*dd_idx) += 2; /* D D P Q D */ + ddf_layout = 1; break; case ALGORITHM_ROTATING_N_RESTART: @@ -1400,6 +1408,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, qd_idx = 0; } else if (*dd_idx >= pd_idx) (*dd_idx) += 2; /* D D P Q D */ + ddf_layout = 1; break; case ALGORITHM_ROTATING_N_CONTINUE: @@ -1407,6 +1416,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, pd_idx = raid_disks - 1 - (stripe % raid_disks); qd_idx = (pd_idx + raid_disks - 1) % raid_disks; *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; + ddf_layout = 1; break; case ALGORITHM_LEFT_ASYMMETRIC_6: @@ -1454,6 +1464,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, if (sh) { sh->pd_idx = pd_idx; sh->qd_idx = qd_idx; + sh->ddf_layout = ddf_layout; } /* * Finally, compute the new sector number @@ -1642,9 +1653,10 @@ static void compute_parity6(struct stripe_head *sh, int method) { raid5_conf_t *conf = sh->raid_conf; int i, pd_idx, qd_idx, d0_idx, disks = sh->disks, count; + int syndrome_disks = sh->ddf_layout ? disks : (disks - 2); struct bio *chosen; /**** FIX THIS: This could be very bad if disks is close to 256 ****/ - void *ptrs[disks]; + void *ptrs[syndrome_disks+2]; pd_idx = sh->pd_idx; qd_idx = sh->qd_idx; @@ -1687,23 +1699,28 @@ static void compute_parity6(struct stripe_head *sh, int method) } /* Note that unlike RAID-5, the ordering of the disks matters greatly.*/ - /* FIX: Is this ordering of drives even remotely optimal? */ + + for (i = 0; i < disks; i++) + ptrs[i] = (void *)raid6_empty_zero_page; + count = 0; i = d0_idx; do { - int slot = raid6_idx_to_slot(i, sh, &count); + int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); + ptrs[slot] = page_address(sh->dev[i].page); - if (slot < sh->disks - 2 && + if (slot < syndrome_disks && !test_bit(R5_UPTODATE, &sh->dev[i].flags)) { printk(KERN_ERR "block %d/%d not uptodate " "on parity calc\n", i, count); BUG(); } + i = raid6_next_disk(i, disks); } while (i != d0_idx); - BUG_ON(count+2 != disks); + BUG_ON(count != syndrome_disks); - raid6_call.gen_syndrome(disks, STRIPE_SIZE, ptrs); + raid6_call.gen_syndrome(syndrome_disks+2, STRIPE_SIZE, ptrs); switch(method) { case RECONSTRUCT_WRITE: @@ -1761,24 +1778,28 @@ static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) { int i, count, disks = sh->disks; + int syndrome_disks = sh->ddf_layout ? disks : disks-2; int d0_idx = raid6_d0(sh); int faila = -1, failb = -1; /**** FIX THIS: This could be very bad if disks is close to 256 ****/ - void *ptrs[disks]; + void *ptrs[syndrome_disks+2]; + for (i = 0; i < disks ; i++) + ptrs[i] = (void *)raid6_empty_zero_page; count = 0; i = d0_idx; do { - int slot; - slot = raid6_idx_to_slot(i, sh, &count); + int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); + ptrs[slot] = page_address(sh->dev[i].page); + if (i == dd_idx1) faila = slot; if (i == dd_idx2) failb = slot; i = raid6_next_disk(i, disks); } while (i != d0_idx); - BUG_ON(count+2 != disks); + BUG_ON(count != syndrome_disks); BUG_ON(faila == failb); if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } @@ -1787,9 +1808,9 @@ static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) (unsigned long long)sh->sector, dd_idx1, dd_idx2, faila, failb); - if ( failb == disks-1 ) { + if (failb == syndrome_disks+1) { /* Q disk is one of the missing disks */ - if ( faila == disks-2 ) { + if (faila == syndrome_disks) { /* Missing P+Q, just recompute */ compute_parity6(sh, UPDATE_PARITY); return; @@ -1804,12 +1825,13 @@ static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) } /* We're missing D+P or D+D; */ - if (failb == disks-2) { + if (failb == syndrome_disks) { /* We're missing D+P. */ - raid6_datap_recov(disks, STRIPE_SIZE, faila, ptrs); + raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, faila, ptrs); } else { /* We're missing D+D. */ - raid6_2data_recov(disks, STRIPE_SIZE, faila, failb, ptrs); + raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE, faila, failb, + ptrs); } /* Both the above update both missing blocks */ diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 633d79289616..84456b1af204 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -201,6 +201,7 @@ struct stripe_head { sector_t sector; /* sector of this row */ short pd_idx; /* parity disk index */ short qd_idx; /* 'Q' disk index for raid6 */ + short ddf_layout;/* use DDF ordering to calculate Q */ unsigned long state; /* state flags */ atomic_t count; /* nr of active thread/requests */ spinlock_t lock; |