diff options
Diffstat (limited to 'drivers/md/raid10.c')
-rw-r--r-- | drivers/md/raid10.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index f6d2be1d2..bee694be2 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -781,8 +781,16 @@ static struct md_rdev *read_balance(struct r10conf *conf, disk = r10_bio->devs[slot].devnum; rdev = rcu_dereference(conf->mirrors[disk].replacement); if (rdev == NULL || test_bit(Faulty, &rdev->flags) || - r10_bio->devs[slot].addr + sectors > rdev->recovery_offset) + r10_bio->devs[slot].addr + sectors > + rdev->recovery_offset) { + /* + * Read replacement first to prevent reading both rdev + * and replacement as NULL during replacement replace + * rdev. + */ + smp_mb(); rdev = rcu_dereference(conf->mirrors[disk].rdev); + } if (rdev == NULL || test_bit(Faulty, &rdev->flags)) continue; @@ -934,6 +942,7 @@ static void flush_pending_writes(struct r10conf *conf) else generic_make_request(bio); bio = next; + cond_resched(); } blk_finish_plug(&plug); } else @@ -1119,6 +1128,7 @@ static void raid10_unplug(struct blk_plug_cb *cb, bool from_schedule) else generic_make_request(bio); bio = next; + cond_resched(); } kfree(plug); } @@ -1400,9 +1410,15 @@ retry_write: for (i = 0; i < conf->copies; i++) { int d = r10_bio->devs[i].devnum; - struct md_rdev *rdev = rcu_dereference(conf->mirrors[d].rdev); - struct md_rdev *rrdev = rcu_dereference( - conf->mirrors[d].replacement); + struct md_rdev *rdev, *rrdev; + + rrdev = rcu_dereference(conf->mirrors[d].replacement); + /* + * Read replacement first to prevent reading both rdev and + * replacement as NULL during replacement replace rdev. + */ + smp_mb(); + rdev = rcu_dereference(conf->mirrors[d].rdev); if (rdev == rrdev) rrdev = NULL; if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |