diff options
Diffstat (limited to 'drivers/md/raid5-cache.c')
| -rw-r--r-- | drivers/md/raid5-cache.c | 61 |
1 files changed, 46 insertions, 15 deletions
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index f253a9c583c1..5d7da1c700aa 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -236,9 +236,10 @@ struct r5l_io_unit { bool need_split_bio; struct bio *split_bio; - unsigned int has_flush:1; /* include flush request */ - unsigned int has_fua:1; /* include fua request */ - unsigned int has_null_flush:1; /* include empty flush request */ + unsigned int has_flush:1; /* include flush request */ + unsigned int has_fua:1; /* include fua request */ + unsigned int has_null_flush:1; /* include null flush request */ + unsigned int has_flush_payload:1; /* include flush payload */ /* * io isn't sent yet, flush/fua request can only be submitted till it's * the first IO in running_ios list @@ -571,6 +572,8 @@ static void r5l_log_endio(struct bio *bio) struct r5l_io_unit *io_deferred; struct r5l_log *log = io->log; unsigned long flags; + bool has_null_flush; + bool has_flush_payload; if (bio->bi_status) md_error(log->rdev->mddev, log->rdev); @@ -580,6 +583,16 @@ static void r5l_log_endio(struct bio *bio) spin_lock_irqsave(&log->io_list_lock, flags); __r5l_set_io_unit_state(io, IO_UNIT_IO_END); + + /* + * if the io doesn't not have null_flush or flush payload, + * it is not safe to access it after releasing io_list_lock. + * Therefore, it is necessary to check the condition with + * the lock held. + */ + has_null_flush = io->has_null_flush; + has_flush_payload = io->has_flush_payload; + if (log->need_cache_flush && !list_empty(&io->stripe_list)) r5l_move_to_end_ios(log); else @@ -600,19 +613,23 @@ static void r5l_log_endio(struct bio *bio) if (log->need_cache_flush) md_wakeup_thread(log->rdev->mddev->thread); - if (io->has_null_flush) { + /* finish flush only io_unit and PAYLOAD_FLUSH only io_unit */ + if (has_null_flush) { struct bio *bi; WARN_ON(bio_list_empty(&io->flush_barriers)); while ((bi = bio_list_pop(&io->flush_barriers)) != NULL) { bio_endio(bi); - atomic_dec(&io->pending_stripe); + if (atomic_dec_and_test(&io->pending_stripe)) { + __r5l_stripe_write_finished(io); + return; + } } } - - /* finish flush only io_unit and PAYLOAD_FLUSH only io_unit */ - if (atomic_read(&io->pending_stripe) == 0) - __r5l_stripe_write_finished(io); + /* decrease pending_stripe for flush payload */ + if (has_flush_payload) + if (atomic_dec_and_test(&io->pending_stripe)) + __r5l_stripe_write_finished(io); } static void r5l_do_submit_io(struct r5l_log *log, struct r5l_io_unit *io) @@ -881,6 +898,11 @@ static void r5l_append_flush_payload(struct r5l_log *log, sector_t sect) payload->size = cpu_to_le32(sizeof(__le64)); payload->flush_stripes[0] = cpu_to_le64(sect); io->meta_offset += meta_size; + /* multiple flush payloads count as one pending_stripe */ + if (!io->has_flush_payload) { + io->has_flush_payload = 1; + atomic_inc(&io->pending_stripe); + } mutex_unlock(&log->io_mutex); } @@ -2540,23 +2562,32 @@ static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page) */ int r5c_journal_mode_set(struct mddev *mddev, int mode) { - struct r5conf *conf = mddev->private; - struct r5l_log *log = conf->log; - - if (!log) - return -ENODEV; + struct r5conf *conf; + int err; if (mode < R5C_JOURNAL_MODE_WRITE_THROUGH || mode > R5C_JOURNAL_MODE_WRITE_BACK) return -EINVAL; + err = mddev_lock(mddev); + if (err) + return err; + conf = mddev->private; + if (!conf || !conf->log) { + mddev_unlock(mddev); + return -ENODEV; + } + if (raid5_calc_degraded(conf) > 0 && - mode == R5C_JOURNAL_MODE_WRITE_BACK) + mode == R5C_JOURNAL_MODE_WRITE_BACK) { + mddev_unlock(mddev); return -EINVAL; + } mddev_suspend(mddev); conf->log->r5c_journal_mode = mode; mddev_resume(mddev); + mddev_unlock(mddev); pr_debug("md/raid:%s: setting r5c cache mode to %d: %s\n", mdname(mddev), mode, r5c_journal_mode_str[mode]); |