diff options
| -rw-r--r-- | drivers/md/raid5-cache.c | 63 |
1 files changed, 62 insertions, 1 deletions
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index d3b5441b4c11..7071c7598f5d 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -85,6 +85,7 @@ struct r5l_log { spinlock_t no_space_stripes_lock; bool need_cache_flush; + bool in_teardown; }; /* @@ -644,6 +645,60 @@ void r5l_flush_stripe_to_raid(struct r5l_log *log) } static void r5l_write_super(struct r5l_log *log, sector_t cp); +static void r5l_write_super_and_discard_space(struct r5l_log *log, + sector_t end) +{ + struct block_device *bdev = log->rdev->bdev; + struct mddev *mddev; + + r5l_write_super(log, end); + + if (!blk_queue_discard(bdev_get_queue(bdev))) + return; + + mddev = log->rdev->mddev; + /* + * This is to avoid a deadlock. r5l_quiesce holds reconfig_mutex and + * wait for this thread to finish. This thread waits for + * MD_CHANGE_PENDING clear, which is supposed to be done in + * md_check_recovery(). md_check_recovery() tries to get + * reconfig_mutex. Since r5l_quiesce already holds the mutex, + * md_check_recovery() fails, so the PENDING never get cleared. The + * in_teardown check workaround this issue. + */ + if (!log->in_teardown) { + set_bit(MD_CHANGE_DEVS, &mddev->flags); + set_bit(MD_CHANGE_PENDING, &mddev->flags); + md_wakeup_thread(mddev->thread); + wait_event(mddev->sb_wait, + !test_bit(MD_CHANGE_PENDING, &mddev->flags) || + log->in_teardown); + /* + * r5l_quiesce could run after in_teardown check and hold + * mutex first. Superblock might get updated twice. + */ + if (log->in_teardown) + md_update_sb(mddev, 1); + } else { + WARN_ON(!mddev_is_locked(mddev)); + md_update_sb(mddev, 1); + } + + if (log->last_checkpoint < end) { + blkdev_issue_discard(bdev, + log->last_checkpoint + log->rdev->data_offset, + end - log->last_checkpoint, GFP_NOIO, 0); + } else { + blkdev_issue_discard(bdev, + log->last_checkpoint + log->rdev->data_offset, + log->device_size - log->last_checkpoint, + GFP_NOIO, 0); + blkdev_issue_discard(bdev, log->rdev->data_offset, end, + GFP_NOIO, 0); + } +} + + static void r5l_do_reclaim(struct r5l_log *log) { sector_t reclaim_target = xchg(&log->reclaim_target, 0); @@ -685,7 +740,7 @@ static void r5l_do_reclaim(struct r5l_log *log) * here, because the log area might be reused soon and we don't want to * confuse recovery */ - r5l_write_super(log, next_checkpoint); + r5l_write_super_and_discard_space(log, next_checkpoint); mutex_lock(&log->io_mutex); log->last_checkpoint = next_checkpoint; @@ -721,9 +776,11 @@ static void r5l_wake_reclaim(struct r5l_log *log, sector_t space) void r5l_quiesce(struct r5l_log *log, int state) { + struct mddev *mddev; if (!log || state == 2) return; if (state == 0) { + log->in_teardown = 0; log->reclaim_thread = md_register_thread(r5l_reclaim_thread, log->rdev->mddev, "reclaim"); } else if (state == 1) { @@ -731,6 +788,10 @@ void r5l_quiesce(struct r5l_log *log, int state) * at this point all stripes are finished, so io_unit is at * least in STRIPE_END state */ + log->in_teardown = 1; + /* make sure r5l_write_super_and_discard_space exits */ + mddev = log->rdev->mddev; + wake_up(&mddev->sb_wait); r5l_wake_reclaim(log, -1L); md_unregister_thread(&log->reclaim_thread); r5l_do_reclaim(log); |