linux/drivers/md/raid5-cache.c, branch v4.9

raid5-cache: correct condition for empty metadata write

2016-10-29T05:04:03Z

As long as we recover one metadata block, we should write the empty metadata write. The original code could make recovery corrupted if only one meta is valid. Reported-by: Zhengyuan Liu Signed-off-by: Shaohua Li

md/raid5: write an empty meta-block when creating log super-block

2016-10-24T22:28:18Z

If superblock points to an invalid meta block, r5l_load_log will set create_super with true and create an new superblock, this runtime path would always happen if we do no writing I/O to this array since it was created. Writing an empty meta block could avoid this unnecessary action at the first time we created log superblock. Another reason is for the corretness of log recovery. Currently we have bellow code to guarantee log revocery to be correct. if (ctx.seq > log->last_cp_seq + 1) { int ret; ret = r5l_log_write_empty_meta_block(log, ctx.pos, ctx.seq + 10); if (ret) return ret; log->seq = ctx.seq + 11; log->log_start = r5l_ring_add(log, ctx.pos, BLOCK_SECTORS); r5l_write_super(log, ctx.pos); } else { log->log_start = ctx.pos; log->seq = ctx.seq; } If we just created a array with a journal device, log->log_start and log->last_checkpoint should all be 0, then we write three meta block which are valid except mid one and supposed crash happened. The ctx.seq would equal to log->last_cp_seq + 1 and log->log_start would be set to position of mid invalid meta block after we did a recovery, this will lead to problems which could be avoided with this patch. Signed-off-by: Zhengyuan Liu Signed-off-by: Shaohua Li

md/raid5: initialize next_checkpoint field before use

2016-10-24T22:28:18Z

No initial operation was done to this field when we load/recovery the log, it got assignment only when IO to raid disk was finished. So r5l_quiesce may use wrong next_checkpoint to reclaim log space, that would make reclaimable space calculation confused. Signed-off-by: Zhengyuan Liu Signed-off-by: Shaohua Li

raid5-cache: fix a deadlock in superblock write

2016-08-31T16:05:18Z

There is a potential deadlock in superblock write. Discard could zero data, so before discard we must make sure superblock is updated to new log tail. Updating superblock (either directly call md_update_sb() or depend on md thread) must hold reconfig mutex. On the other hand, raid5_quiesce is called with reconfig_mutex hold. The first step of raid5_quiesce() is waitting for all IO finish, hence waitting for reclaim thread, while reclaim thread is calling this function and waitting for reconfig mutex. So there is a deadlock. We workaround this issue with a trylock. The downside of the solution is we could miss discard if we can't take reconfig mutex. But this should happen rarely (mainly in raid array stop), so miss discard shouldn't be a big problem. Cc: NeilBrown Signed-off-by: Shaohua Li

block: rename bio bi_rw to bi_opf

2016-08-07T20:41:02Z

Since commit 63a4cc24867d, bio->bi_rw contains flags in the lower portion and the op code in the higher portions. This means that old code that relies on manually setting bi_rw is most likely going to be broken. Instead of letting that brokeness linger, rename the member, to force old and out-of-tree code to break at compile time instead of at runtime. No intended functional changes in this commit. Signed-off-by: Jens Axboe

block, drivers, fs: rename REQ_FLUSH to REQ_PREFLUSH

2016-06-07T19:41:38Z

To avoid confusion between REQ_OP_FLUSH, which is handled by request_fn drivers, and upper layers requesting the block layer perform a flush sequence along with possibly a WRITE, this patch renames REQ_FLUSH to REQ_PREFLUSH. Signed-off-by: Mike Christie Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe

md: use bio op accessors

2016-06-07T19:41:38Z

Separate the op from the rq_flag_bits and have md set/get the bio using bio_set_op_attrs/bio_op. Signed-off-by: Mike Christie Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe

block/fs/drivers: remove rw argument from submit_bio

2016-06-07T19:41:38Z

This has callers of submit_bio/submit_bio_wait set the bio->bi_rw instead of passing it in. This makes that use the same as generic_make_request and how we set the other bio fields. Signed-off-by: Mike Christie Fixed up fs/ext4/crypto.c Signed-off-by: Jens Axboe

Merge tag 'md/4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

2016-05-20T00:25:13Z

Pull MD updates from Shaohua Li: "Several patches from Guoqing fixing md-cluster bugs and several patches from Heinz fixing dm-raid bugs" * tag 'md/4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: md-cluster: check the return value of process_recvd_msg md-cluster: gather resync infos and enable recv_thread after bitmap is ready md: set MD_CHANGE_PENDING in a atomic region md: raid5: add prerequisite to run underneath dm-raid md: raid10: add prerequisite to run underneath dm-raid md: md.c: fix oops in mddev_suspend for raid0 md-cluster: fix ifnullfree.cocci warnings md-cluster/bitmap: unplug bitmap to sync dirty pages to disk md-cluster/bitmap: fix wrong page num in bitmap_file_clear_bit and bitmap_file_set_bit md-cluster/bitmap: fix wrong calcuation of offset md-cluster: sync bitmap when node received RESYNCING msg md-cluster: always setup in-memory bitmap md-cluster: wakeup thread if activated a spare disk md-cluster: change array_sectors and update size are not supported md-cluster: fix locking when node joins cluster during message broadcast md-cluster: unregister thread if err happened md-cluster: wake up thread to continue recovery md-cluser: make resync_finish only called after pers->sync_request md-cluster: change resync lock from asynchronous to synchronous

md: set MD_CHANGE_PENDING in a atomic region

2016-05-09T16:24:02Z

Some code waits for a metadata update by: 1. flagging that it is needed (MD_CHANGE_DEVS or MD_CHANGE_CLEAN) 2. setting MD_CHANGE_PENDING and waking the management thread 3. waiting for MD_CHANGE_PENDING to be cleared If the first two are done without locking, the code in md_update_sb() which checks if it needs to repeat might test if an update is needed before step 1, then clear MD_CHANGE_PENDING after step 2, resulting in the wait returning early. So make sure all places that set MD_CHANGE_PENDING are atomicial, and bit_clear_unless (suggested by Neil) is introduced for the purpose. Cc: Martin Kepplinger Cc: Andrew Morton Cc: Denys Vlasenko Cc: Sasha Levin Cc: Reviewed-by: NeilBrown Signed-off-by: Guoqing Jiang Signed-off-by: Shaohua Li