diff options
Diffstat (limited to 'drivers/md/raid5.c')
| -rw-r--r-- | drivers/md/raid5.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index d79ecd903269..4263df11d597 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -4408,8 +4408,10 @@ static void make_request(struct mddev *mddev, struct bio * bi) for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { DEFINE_WAIT(w); int previous; + int seq; retry: + seq = read_seqcount_begin(&conf->gen_lock); previous = 0; prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); if (unlikely(conf->reshape_progress != MaxSector)) { @@ -4442,7 +4444,7 @@ static void make_request(struct mddev *mddev, struct bio * bi) previous, &dd_idx, NULL); pr_debug("raid456: make_request, sector %llu logical %llu\n", - (unsigned long long)new_sector, + (unsigned long long)new_sector, (unsigned long long)logical_sector); sh = get_active_stripe(conf, new_sector, previous, @@ -4471,6 +4473,13 @@ static void make_request(struct mddev *mddev, struct bio * bi) goto retry; } } + if (read_seqcount_retry(&conf->gen_lock, seq)) { + /* Might have got the wrong stripe_head + * by accident + */ + release_stripe(sh); + goto retry; + } if (rw == WRITE && logical_sector >= mddev->suspend_lo && @@ -5437,6 +5446,7 @@ static struct r5conf *setup_conf(struct mddev *mddev) if (alloc_thread_groups(conf, 0)) goto abort; spin_lock_init(&conf->device_lock); + seqcount_init(&conf->gen_lock); init_waitqueue_head(&conf->wait_for_stripe); init_waitqueue_head(&conf->wait_for_overlap); INIT_LIST_HEAD(&conf->handle_list); @@ -6249,6 +6259,7 @@ static int raid5_start_reshape(struct mddev *mddev) atomic_set(&conf->reshape_stripes, 0); spin_lock_irq(&conf->device_lock); + write_seqcount_begin(&conf->gen_lock); conf->previous_raid_disks = conf->raid_disks; conf->raid_disks += mddev->delta_disks; conf->prev_chunk_sectors = conf->chunk_sectors; @@ -6265,6 +6276,7 @@ static int raid5_start_reshape(struct mddev *mddev) else conf->reshape_progress = 0; conf->reshape_safe = conf->reshape_progress; + write_seqcount_end(&conf->gen_lock); spin_unlock_irq(&conf->device_lock); /* Add some new drives, as many as will fit. |