diff options
| -rw-r--r-- | drivers/md/raid5.c | 72 |
1 files changed, 59 insertions, 13 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 3705585d7567..71d1de909ba5 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -488,6 +488,27 @@ get_active_stripe(struct r5conf *conf, sector_t sector, return sh; } +/* Determine if 'data_offset' or 'new_data_offset' should be used + * in this stripe_head. + */ +static int use_new_offset(struct r5conf *conf, struct stripe_head *sh) +{ + sector_t progress = conf->reshape_progress; + /* Need a memory barrier to make sure we see the value + * of conf->generation, or ->data_offset that was set before + * reshape_progress was updated. + */ + smp_rmb(); + if (progress == MaxSector) + return 0; + if (sh->generation == conf->generation - 1) + return 0; + /* We are in a reshape, and this is a new-generation stripe, + * so use new_data_offset. + */ + return 1; +} + static void raid5_end_read_request(struct bio *bi, int error); static void @@ -603,7 +624,12 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) __func__, (unsigned long long)sh->sector, bi->bi_rw, i); atomic_inc(&sh->count); - bi->bi_sector = sh->sector + rdev->data_offset; + if (use_new_offset(conf, sh)) + bi->bi_sector = (sh->sector + + rdev->new_data_offset); + else + bi->bi_sector = (sh->sector + + rdev->data_offset); bi->bi_flags = 1 << BIO_UPTODATE; bi->bi_idx = 0; bi->bi_io_vec[0].bv_len = STRIPE_SIZE; @@ -627,7 +653,12 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) __func__, (unsigned long long)sh->sector, rbi->bi_rw, i); atomic_inc(&sh->count); - rbi->bi_sector = sh->sector + rrdev->data_offset; + if (use_new_offset(conf, sh)) + rbi->bi_sector = (sh->sector + + rrdev->new_data_offset); + else + rbi->bi_sector = (sh->sector + + rrdev->data_offset); rbi->bi_flags = 1 << BIO_UPTODATE; rbi->bi_idx = 0; rbi->bi_io_vec[0].bv_len = STRIPE_SIZE; @@ -1648,7 +1679,7 @@ static void raid5_end_read_request(struct bio * bi, int error) int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); char b[BDEVNAME_SIZE]; struct md_rdev *rdev = NULL; - + sector_t s; for (i=0 ; i<disks; i++) if (bi == &sh->dev[i].req) @@ -1671,6 +1702,10 @@ static void raid5_end_read_request(struct bio * bi, int error) if (!rdev) rdev = conf->disks[i].rdev; + if (use_new_offset(conf, sh)) + s = sh->sector + rdev->new_data_offset; + else + s = sh->sector + rdev->data_offset; if (uptodate) { set_bit(R5_UPTODATE, &sh->dev[i].flags); if (test_bit(R5_ReadError, &sh->dev[i].flags)) { @@ -1683,8 +1718,7 @@ static void raid5_end_read_request(struct bio * bi, int error) "md/raid:%s: read error corrected" " (%lu sectors at %llu on %s)\n", mdname(conf->mddev), STRIPE_SECTORS, - (unsigned long long)(sh->sector - + rdev->data_offset), + (unsigned long long)s, bdevname(rdev->bdev, b)); atomic_add(STRIPE_SECTORS, &rdev->corrected_errors); clear_bit(R5_ReadError, &sh->dev[i].flags); @@ -1704,8 +1738,7 @@ static void raid5_end_read_request(struct bio * bi, int error) "md/raid:%s: read error on replacement device " "(sector %llu on %s).\n", mdname(conf->mddev), - (unsigned long long)(sh->sector - + rdev->data_offset), + (unsigned long long)s, bdn); else if (conf->mddev->degraded >= conf->max_degraded) printk_ratelimited( @@ -1713,8 +1746,7 @@ static void raid5_end_read_request(struct bio * bi, int error) "md/raid:%s: read error not correctable " "(sector %llu on %s).\n", mdname(conf->mddev), - (unsigned long long)(sh->sector - + rdev->data_offset), + (unsigned long long)s, bdn); else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) /* Oh, no!!! */ @@ -1723,8 +1755,7 @@ static void raid5_end_read_request(struct bio * bi, int error) "md/raid:%s: read error NOT corrected!! " "(sector %llu on %s).\n", mdname(conf->mddev), - (unsigned long long)(sh->sector - + rdev->data_offset), + (unsigned long long)s, bdn); else if (atomic_read(&rdev->read_errors) > conf->max_nr_stripes) @@ -3842,6 +3873,7 @@ static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio) raid_bio->bi_next = (void*)rdev; align_bi->bi_bdev = rdev->bdev; align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); + /* No reshape active, so we can trust rdev->data_offset */ align_bi->bi_sector += rdev->data_offset; if (!bio_fits_rdev(align_bi) || @@ -5182,9 +5214,12 @@ static int run(struct mddev *mddev) blk_queue_io_opt(mddev->queue, chunk_size * (conf->raid_disks - conf->max_degraded)); - rdev_for_each(rdev, mddev) + rdev_for_each(rdev, mddev) { disk_stack_limits(mddev->gendisk, rdev->bdev, rdev->data_offset << 9); + disk_stack_limits(mddev->gendisk, rdev->bdev, + rdev->new_data_offset << 9); + } } return 0; @@ -5539,12 +5574,16 @@ static int raid5_start_reshape(struct mddev *mddev) conf->chunk_sectors = mddev->new_chunk_sectors; conf->prev_algo = conf->algorithm; conf->algorithm = mddev->new_layout; + conf->generation++; + /* Code that selects data_offset needs to see the generation update + * if reshape_progress has been set - so a memory barrier needed. + */ + smp_mb(); if (mddev->reshape_backwards) conf->reshape_progress = raid5_size(mddev, 0, 0); else conf->reshape_progress = 0; conf->reshape_safe = conf->reshape_progress; - conf->generation++; spin_unlock_irq(&conf->device_lock); /* Add some new drives, as many as will fit. @@ -5596,6 +5635,9 @@ static int raid5_start_reshape(struct mddev *mddev) mddev->recovery = 0; spin_lock_irq(&conf->device_lock); mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; + rdev_for_each(rdev, mddev) + rdev->new_data_offset = rdev->data_offset; + smp_wmb(); conf->reshape_progress = MaxSector; mddev->reshape_position = MaxSector; spin_unlock_irq(&conf->device_lock); @@ -5614,9 +5656,13 @@ static void end_reshape(struct r5conf *conf) { if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { + struct md_rdev *rdev; spin_lock_irq(&conf->device_lock); conf->previous_raid_disks = conf->raid_disks; + rdev_for_each(rdev, conf->mddev) + rdev->data_offset = rdev->new_data_offset; + smp_wmb(); conf->reshape_progress = MaxSector; spin_unlock_irq(&conf->device_lock); wake_up(&conf->wait_for_overlap); |