diff options
| author |   Song Liu <songliubraving@fb.com> | 2017-05-11 15:28:28 -0700 |
|---|---|---|
| committer |   Shaohua Li <shli@fb.com> | 2017-05-11 22:11:11 -0700 |
| commit | 70d466f760b351fe30b5f8c956354ddf29aa676b (patch) | |
| tree | 1e9cb8b69fb904173cb9fcf7d900c3be4bc91ab3 /drivers/md/raid5-log.h | |
| parent | md/raid1/10: avoid unnecessary locking (diff) | |
| download | linux-dev-70d466f760b351fe30b5f8c956354ddf29aa676b.tar.xz linux-dev-70d466f760b351fe30b5f8c956354ddf29aa676b.zip | |
md/r5cache: gracefully handle journal device errors for writeback mode
For the raid456 with writeback cache, when journal device failed during
normal operation, it is still possible to persist all data, as all
pending data is still in stripe cache. However, it is necessary to handle
journal failure gracefully.
During journal failures, the following logic handles the graceful shutdown
of journal:
1. raid5_error() marks the device as Faulty and schedules async work
log->disable_writeback_work;
2. In disable_writeback_work (r5c_disable_writeback_async), the mddev is
suspended, set to write through, and then resumed. mddev_suspend()
flushes all cached stripes;
3. All cached stripes need to be flushed carefully to the RAID array.
This patch fixes issues within the process above:
1. In r5c_update_on_rdev_error() schedule disable_writeback_work for
journal failures;
2. In r5c_disable_writeback_async(), wait for MD_SB_CHANGE_PENDING,
since raid5_error() updates superblock.
3. In handle_stripe(), allow stripes with data in journal (s.injournal > 0)
to make progress during log_failed;
4. In delay_towrite(), if log failed only process data in the cache (skip
new writes in dev->towrite);
5. In __get_priority_stripe(), process loprio_list during journal device
failures.
6. In raid5_remove_disk(), wait for all cached stripes are flushed before
calling log_exit().
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Diffstat (limited to 'drivers/md/raid5-log.h')
| -rw-r--r-- | drivers/md/raid5-log.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/md/raid5-log.h b/drivers/md/raid5-log.h index 27097101ccca..328d67aedda4 100644 --- a/drivers/md/raid5-log.h +++ b/drivers/md/raid5-log.h @@ -28,7 +28,8 @@ extern void r5c_flush_cache(struct r5conf *conf, int num); extern void r5c_check_stripe_cache_usage(struct r5conf *conf); extern void r5c_check_cached_full_stripe(struct r5conf *conf); extern struct md_sysfs_entry r5c_journal_mode; -extern void r5c_update_on_rdev_error(struct mddev *mddev); +extern void r5c_update_on_rdev_error(struct mddev *mddev, + struct md_rdev *rdev); extern bool r5c_big_stripe_cached(struct r5conf *conf, sector_t sect); extern struct dma_async_tx_descriptor * |