Hi maintainers and folks, This patch set tries to improve bcache device failure handling, includes cache device and backing device failures.
The basic idea to handle failed cache device is, - Unregister cache set - Detach all backing devices which are attached to this cache set - Stop all the detached bcache devices (configurable) - Stop all flash only volume on the cache set The above process is named 'cache set retire' by me. The result of cache set retire is, cache set and bcache devices are all removed, following I/O requests will get failed immediately to notift upper layer or user space coce that the cache device is failed or disconnected. - Stop all the detached bcache devices (configurable) - Stop all flash only volume on the cache set The above process is named 'cache set retire' by me. The result of cache set retire is, cache set and bcache devices are all removed (configurable), following I/O requests will get failed immediately to notify upper layer or user space coce that the cache device is failed or disconnected. one patch from v5 patch set is merged into bcache-for-next, which is not in v6 patch set any longer. The changes of v6 patch set are only for typo fix, which were pointed out by Nix, Michael and other developers. So far all patches have peer review, thank you all, bcache developers! Changelog: v6: fix typo and mistaken spelling. v5: replace patch "bcache: stop all attached bcache devices for a retired cache set" from v4 patch set by "bcache: add stop_when_cache_set_failed option to backing device" from v5 patch set. fix issues from v4 patch set. improve kernel message format, remove redundant prefix string. v4: add per-cached_dev option stop_attached_devs_on_fail to avoid stopping attached bcache device from a retiring cache set. v3: fix detach issue find in v2 patch set. v2: fixes all problems found in v1 review. add patches to handle backing device failure. add one more patch to set writeback_rate_update_seconds range. include a patch from Junhui Tang. v1: the initial version, only handles cache device failure. Coly Li --- Coly Li (8): bcache: fix cached_dev->count usage for bch_cache_set_error() bcache: quit dc->writeback_thread when BCACHE_DEV_DETACHING is set bcache: stop dc->writeback_rate_update properly bcache: add CACHE_SET_IO_DISABLE to struct cache_set flags bcache: add stop_when_cache_set_failed option to backing device bcache: add backing_request_endio() for bi_end_io of attached backing device I/O bcache: add io_disable to struct cached_dev bcache: stop bcache device when backing device is offline Tang Junhui (1): bcache: fix inaccurate io state for detached bcache devices drivers/md/bcache/alloc.c | 3 +- drivers/md/bcache/bcache.h | 44 ++++++++- drivers/md/bcache/btree.c | 10 ++- drivers/md/bcache/io.c | 16 +++- drivers/md/bcache/journal.c | 4 +- drivers/md/bcache/request.c | 185 ++++++++++++++++++++++++++++++++------ drivers/md/bcache/super.c | 205 ++++++++++++++++++++++++++++++++++++++---- drivers/md/bcache/sysfs.c | 55 +++++++++++- drivers/md/bcache/util.h | 6 -- drivers/md/bcache/writeback.c | 92 ++++++++++++++++--- drivers/md/bcache/writeback.h | 2 - 11 files changed, 543 insertions(+), 79 deletions(-) -- 2.16.1