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2017-12-01md/raid5: correct degraded calculation in raid5_errorbingjingc1-1/+1
When disk failure occurs on new disks for reshape, mddev->degraded is not calculated correctly. Faulty bit of the failure device is not set before raid5_calc_degraded(conf). mdadm --create /dev/md0 --level=5 --raid-devices=3 /dev/loop[012] mdadm /dev/md0 -a /dev/loop3 mdadm /dev/md0 --grow -n4 mdadm /dev/md0 -f /dev/loop3 # simulating disk failure cat /sys/block/md0/md/degraded # it outputs 0, but it should be 1. However, mdadm -D /dev/md0 will show that it is degraded. It's a bug. It can be fixed by moving the resources raid5_calc_degraded() depends on before it. Reported-by: Roy Chung <roychung@synology.com> Reviewed-by: Alex Wu <alexwu@synology.com> Signed-off-by: BingJing Chang <bingjingc@synology.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-14Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/mdLinus Torvalds1-37/+42
Pull MD update from Shaohua Li: "This update mostly includes bug fixes: - md-cluster now supports raid10 from Guoqing - raid5 PPL fixes from Artur - badblock regression fix from Bo - suspend hang related fixes from Neil - raid5 reshape fixes from Neil - raid1 freeze deadlock fix from Nate - memleak fixes from Zdenek - bitmap related fixes from Me and Tao - other fixes and cleanups" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: (33 commits) md: free unused memory after bitmap resize md: release allocated bitset sync_set md/bitmap: clear BITMAP_WRITE_ERROR bit before writing it to sb md: be cautious about using ->curr_resync_completed for ->recovery_offset badblocks: fix wrong return value in badblocks_set if badblocks are disabled md: don't check MD_SB_CHANGE_CLEAN in md_allow_write md-cluster: update document for raid10 md: remove redundant variable q raid1: remove obsolete code in raid1_write_request md-cluster: Use a small window for raid10 resync md-cluster: Suspend writes in RAID10 if within range md-cluster/raid10: set "do_balance = 0" if area is resyncing md: use lockdep_assert_held raid1: prevent freeze_array/wait_all_barriers deadlock md: use TASK_IDLE instead of blocking signals md: remove special meaning of ->quiesce(.., 2) md: allow metadata update while suspending. md: use mddev_suspend/resume instead of ->quiesce() md: move suspend_hi/lo handling into core md code md: don't call bitmap_create() while array is quiesced. ...
2017-11-09md: be cautious about using ->curr_resync_completed for ->recovery_offsetNeilBrown1-0/+24
The ->recovery_offset shows how much of a non-InSync device is actually in sync - how much has been recoveryed. When performing a recovery, ->curr_resync and ->curr_resync_completed follow the device address being recovered and so can be used to update ->recovery_offset. When performing a reshape, ->curr_resync* might follow the device addresses (raid5) or might follow array addresses (raid10), so cannot in general be used to set ->recovery_offset. When reshaping backwards, ->curre_resync* measures from the *end* of the array-or-device, so is particularly unhelpful. So change the common code in md.c to only use ->curr_resync_complete for the simple recovery case, and add code to raid5.c to update ->recovery_offset during a forwards reshape. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-01md: use TASK_IDLE instead of blocking signalsMikulas Patocka1-1/+0
Hi - I submit this patch for the next merge window: Some times ago, I made a patch f9c79bc05a2a that blocks signals around the schedule() calls in MD. The MD subsystem needs to do an uninterruptible sleep that is not accounted in load average - so we block signals and use interruptible sleep. The kernel has a special TASK_IDLE state for this purpose, so we can use it instead of blocking signals. This patch doesn't fix any bug, it just makes the code simpler. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-01md: remove special meaning of ->quiesce(.., 2)NeilBrown1-12/+6
The '2' argument means "wake up anything that is waiting". This is an inelegant part of the design and was added to help support management of suspend_lo/suspend_hi setting. Now that suspend_lo/hi is managed in mddev_suspend/resume, that need is gone. These is still a couple of places where we call 'quiesce' with an argument of '2', but they can safely be changed to call ->quiesce(.., 1); ->quiesce(.., 0) which achieve the same result at the small cost of pausing IO briefly. This removes a small "optimization" from suspend_{hi,lo}_store, but it isn't clear that optimization served a useful purpose. The code now is a lot clearer. Suggested-by: Shaohua Li <shli@kernel.org> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-01md: move suspend_hi/lo handling into core md codeNeilBrown1-22/+0
responding to ->suspend_lo and ->suspend_hi is similar to responding to ->suspended. It is best to wait in the common core code without incrementing ->active_io. This allows mddev_suspend()/mddev_resume() to work while requests are waiting for suspend_lo/hi to change. This is will be important after a subsequent patch which uses mddev_suspend() to synchronize updating for suspend_lo/hi. So move the code for testing suspend_lo/hi out of raid1.c and raid5.c, and place it in md.c Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-01md: forbid a RAID5 from having both a bitmap and a journal.NeilBrown1-0/+7
Having both a bitmap and a journal is pointless. Attempting to do so can corrupt the bitmap if the journal replay happens before the bitmap is initialized. Rather than try to avoid this corruption, simply refuse to allow arrays with both a bitmap and a journal. So: - if raid5_run sees both are present, fail. - if adding a bitmap finds a journal is present, fail - if adding a journal finds a bitmap is present, fail. Cc: stable@vger.kernel.org (4.10+) Signed-off-by: NeilBrown <neilb@suse.com> Tested-by: Joshua Kinard <kumba@gentoo.org> Acked-by: Joshua Kinard <kumba@gentoo.org> Signed-off-by: Shaohua Li <shli@fb.com>
2017-10-25locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns ↵Mark Rutland1-1/+1
to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-18raid5: Set R5_Expanded on parity devices as well as data.NeilBrown1-1/+4
When reshaping a fully degraded raid5/raid6 to a larger nubmer of devices, the new device(s) are not in-sync and so that can make the newly grown stripe appear to be "failed". To avoid this, we set the R5_Expanded flag to say "Even though this device is not fully in-sync, this block is safe so don't treat the device as failed for this stripe". This flag is set for data devices, not not for parity devices. Consequently, if you have a RAID6 with two devices that are partly recovered and a spare, and start a reshape to include the spare, then when the reshape gets past the point where the recovery was up to, it will think the stripes are failed and will get into an infinite loop, failing to make progress. So when contructing parity on an EXPAND_READY stripe, set R5_Expanded. Reported-by: Curt <lightspd@gmail.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-10-16md: rename some drivers/md/ files to have an "md-" prefixMike Snitzer1-1/+1
Motivated by the desire to illiminate the imprecise nature of DM-specific patches being unnecessarily sent to both the MD maintainer and mailing-list. Which is born out of the fact that DM files also reside in drivers/md/ Now all MD-specific files in drivers/md/ start with either "raid" or "md-" and the MAINTAINERS file has been updated accordingly. Shaohua: don't change module name Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-09-27md/raid5: cap worker countShaohua Li1-2/+5
static checker reports a potential integer overflow. Cap the worker count to avoid the overflow. Reported:-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-09-19Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/mdLinus Torvalds1-3/+10
Pull MD fixes from Shaohua Li: "Two small patches to fix long-lived raid5 stripe batch bugs, one from Dennis and the other from me" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: md/raid5: preserve STRIPE_ON_UNPLUG_LIST in break_stripe_batch_list md/raid5: fix a race condition in stripe batch
2017-09-07Merge tag 'md/4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/mdLinus Torvalds1-10/+6
Pull MD updates from Shaohua Li: "This update mainly fixes bugs: - Make raid5 ppl support several ppl from Pawel - Several raid5-cache bug fixes from Song - Bitmap fixes from Neil and Me - One raid1/10 regression fix since 4.12 from Me - Other small fixes and cleanup" * tag 'md/4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: md/bitmap: disable bitmap_resize for file-backed bitmaps. raid5-ppl: Recovery support for multiple partial parity logs md: Runtime support for multiple ppls md/raid0: attach correct cgroup info in bio lib/raid6: align AVX512 constants to 512 bits, not bytes raid5: remove raid5_build_block md/r5cache: call mddev_lock/unlock() in r5c_journal_mode_show md: replace seq_release_private with seq_release md: notify about new spare disk in the container md/raid1/10: reset bio allocated from mempool md/raid5: release/flush io in raid5_do_work() md/bitmap: copy correct data for bitmap super
2017-09-05md/raid5: preserve STRIPE_ON_UNPLUG_LIST in break_stripe_batch_listDennis Yang1-1/+2
In release_stripe_plug(), if a stripe_head has its STRIPE_ON_UNPLUG_LIST set, it indicates that this stripe_head is already in the raid5_plug_cb list and release_stripe() would be called instead to drop a reference count. Otherwise, the STRIPE_ON_UNPLUG_LIST bit would be set for this stripe_head and it will get queued into the raid5_plug_cb list. Since break_stripe_batch_list() did not preserve STRIPE_ON_UNPLUG_LIST, A stripe could be re-added to plug list while it is still on that list in the following situation. If stripe_head A is added to another stripe_head B's batch list, in this case A will have its batch_head != NULL and be added into the plug list. After that, stripe_head B gets handled and called break_stripe_batch_list() to reset all the batched stripe_head(including A which is still on the plug list)'s state and reset their batch_head to NULL. Before the plug list gets processed, if there is another write request comes in and get stripe_head A, A will have its batch_head == NULL (cleared by calling break_stripe_batch_list() on B) and be added to plug list once again. Signed-off-by: Dennis Yang <dennisyang@qnap.com> Cc: stable@vger.kernel.org (v4.1+) Signed-off-by: Shaohua Li <shli@fb.com>
2017-09-05md/raid5: fix a race condition in stripe batchShaohua Li1-2/+8
We have a race condition in below scenario, say have 3 continuous stripes, sh1, sh2 and sh3, sh1 is the stripe_head of sh2 and sh3: CPU1 CPU2 CPU3 handle_stripe(sh3) stripe_add_to_batch_list(sh3) -> lock(sh2, sh3) -> lock batch_lock(sh1) -> add sh3 to batch_list of sh1 -> unlock batch_lock(sh1) clear_batch_ready(sh1) -> lock(sh1) and batch_lock(sh1) -> clear STRIPE_BATCH_READY for all stripes in batch_list -> unlock(sh1) and batch_lock(sh1) ->clear_batch_ready(sh3) -->test_and_clear_bit(STRIPE_BATCH_READY, sh3) --->return 0 as sh->batch == NULL -> sh3->batch_head = sh1 -> unlock (sh2, sh3) In CPU1, handle_stripe will continue handle sh3 even it's in batch stripe list of sh1. By moving sh3->batch_head assignment in to batch_lock, we make it impossible to clear STRIPE_BATCH_READY before batch_head is set. Thanks Stephane for helping debug this tricky issue. Reported-and-tested-by: Stephane Thiell <sthiell@stanford.edu> Cc: stable@vger.kernel.org (v4.1+) Signed-off-by: Shaohua Li <shli@fb.com>
2017-08-28md: Runtime support for multiple pplsPawel Baldysiak1-0/+1
Increase PPL area to 1MB and use it as circular buffer to store PPL. The entry with highest generation number is the latest one. If PPL to be written is larger then space left in a buffer, rewind the buffer to the start (don't wrap it). Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com> Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-08-25raid5: remove raid5_build_blockGuoqing Jiang1-10/+1
Now raid5_build_block is just called to set the sector of r5dev, raid5_compute_blocknr can be used directly for the purpose. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-08-24md/raid5: release/flush io in raid5_do_work()Song Liu1-0/+4
In raid5, there are scenarios where some ios are deferred to a later time, and some IO need a flush to complete. To make sure we make progress with these IOs, we need to call the following functions: flush_deferred_bios(conf); r5l_flush_stripe_to_raid(conf->log); Both of these functions are called in raid5d(), but missing in raid5_do_work(). As a result, these functions are not called when multi-threading (group_thread_cnt > 0) is enabled. This patch adds calls to these function to raid5_do_work(). Note for stable branches: r5l_flush_stripe_to_raid(conf->log) is need for 4.4+ flush_deferred_bios(conf) is only needed for 4.11+ Cc: stable@vger.kernel.org (4.4+) Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-08-23block: replace bi_bdev with a gendisk pointer and partitions indexChristoph Hellwig1-6/+6
This way we don't need a block_device structure to submit I/O. The block_device has different life time rules from the gendisk and request_queue and is usually only available when the block device node is open. Other callers need to explicitly create one (e.g. the lightnvm passthrough code, or the new nvme multipathing code). For the actual I/O path all that we need is the gendisk, which exists once per block device. But given that the block layer also does partition remapping we additionally need a partition index, which is used for said remapping in generic_make_request. Note that all the block drivers generally want request_queue or sometimes the gendisk, so this removes a layer of indirection all over the stack. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23raid5: remove a call to get_start_sectChristoph Hellwig1-1/+3
The block layer always remaps partitions before calling into the ->make_request methods of drivers. Thus the call to get_start_sect in in_chunk_boundary will always return 0 and can be removed. Reviewed-by: Shaohua Li <shli@fb.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-24md/raid5: add thread_group worker async_tx_issue_pending_allOfer Heifetz1-0/+2
Since thread_group worker and raid5d kthread are not in sync, if worker writes stripe before raid5d then requests will be waiting for issue_pendig. Issue observed when building raid5 with ext4, in some build runs jbd2 would get hung and requests were waiting in the HW engine waiting to be issued. Fix this by adding a call to async_tx_issue_pending_all in the raid5_do_work. Signed-off-by: Ofer Heifetz <oferh@marvell.com> Cc: stable@vger.kernel.org Signed-off-by: Shaohua Li <shli@fb.com>
2017-07-21md: simplify code with bio_io_errorGuoqing Jiang1-6/+3
Since bio_io_error sets bi_status to BLK_STS_IOERR, and calls bio_endio, so we can use it directly. And as mentioned by Shaohua, there are also two places in raid5.c can use bio_io_error either. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-07-10Raid5 should update rdev->sectors after reshapeXiao Ni1-3/+1
The raid5 md device is created by the disks which we don't use the total size. For example, the size of the device is 5G and it just uses 3G of the devices to create one raid5 device. Then change the chunksize and wait reshape to finish. After reshape finishing stop the raid and assemble it again. It fails. mdadm -CR /dev/md0 -l5 -n3 /dev/loop[0-2] --size=3G --chunk=32 --assume-clean mdadm /dev/md0 --grow --chunk=64 wait reshape to finish mdadm -S /dev/md0 mdadm -As The error messages: [197519.814302] md: loop1 does not have a valid v1.2 superblock, not importing! [197519.821686] md: md_import_device returned -22 After reshape the data offset is changed. It selects backwards direction in this condition. In function super_1_load it compares the available space of the underlying device with sb->data_size. The new data offset gets bigger after reshape. So super_1_load returns -EINVAL. rdev->sectors is updated in md_finish_reshape. Then sb->data_size is set in super_1_sync based on rdev->sectors. So add md_finish_reshape in end_reshape. Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Guoqing Jiang <gqjiang@suse.com> Cc: stable@vger.kernel.org Signed-off-by: Shaohua Li <shli@fb.com>
2017-07-08Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/mdLinus Torvalds1-9/+13
Pull MD update from Shaohua Li: - fixed deadlock in MD suspend and a potential bug in bio allocation (Neil Brown) - fixed signal issue (Mikulas Patocka) - fixed typo in FailFast test (Guoqing Jiang) - other trival fixes * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: MD: fix sleep in atomic MD: fix a null dereference md: use a separate bio_set for synchronous IO. md: change the initialization value for a spare device spot to MD_DISK_ROLE_SPARE md/raid1: remove unused bio in sync_request_write md/raid10: fix FailFast test for wrong device md: don't use flush_signals in userspace processes md: fix deadlock between mddev_suspend() and md_write_start()
2017-06-18blk: replace bioset_create_nobvec() with a flags arg to bioset_create()NeilBrown1-1/+1
"flags" arguments are often seen as good API design as they allow easy extensibility. bioset_create_nobvec() is implemented internally as a variation in flags passed to __bioset_create(). To support future extension, make the internal structure part of the API. i.e. add a 'flags' argument to bioset_create() and discard bioset_create_nobvec(). Note that the bio_split allocations in drivers/md/raid* do not need the bvec mempool - they should have used bioset_create_nobvec(). Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-13md: don't use flush_signals in userspace processesMikulas Patocka1-1/+4
The function flush_signals clears all pending signals for the process. It may be used by kernel threads when we need to prepare a kernel thread for responding to signals. However using this function for an userspaces processes is incorrect - clearing signals without the program expecting it can cause misbehavior. The raid1 and raid5 code uses flush_signals in its request routine because it wants to prepare for an interruptible wait. This patch drops flush_signals and uses sigprocmask instead to block all signals (including SIGKILL) around the schedule() call. The signals are not lost, but the schedule() call won't respond to them. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Acked-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-06-13md: fix deadlock between mddev_suspend() and md_write_start()NeilBrown1-8/+9
If mddev_suspend() races with md_write_start() we can deadlock with mddev_suspend() waiting for the request that is currently in md_write_start() to complete the ->make_request() call, and md_write_start() waiting for the metadata to be updated to mark the array as 'dirty'. As metadata updates done by md_check_recovery() only happen then the mddev_lock() can be claimed, and as mddev_suspend() is often called with the lock held, these threads wait indefinitely for each other. We fix this by having md_write_start() abort if mddev_suspend() is happening, and ->make_request() aborts if md_write_start() aborted. md_make_request() can detect this abort, decrease the ->active_io count, and wait for mddev_suspend(). Reported-by: Nix <nix@esperi.org.uk> Fix: 68866e425be2(MD: no sync IO while suspended) Cc: stable@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-06-12Merge tag 'v4.12-rc5' into for-4.13/blockJens Axboe1-4/+17
We've already got a few conflicts and upcoming work depends on some of the changes that have gone into mainline as regression fixes for this series. Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream trees to continue working on 4.13 changes. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-09block: switch bios to blk_status_tChristoph Hellwig1-11/+11
Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-05md: initialise ->writes_pending in personality modules.NeilBrown1-0/+3
The new per-cpu counter for writes_pending is initialised in md_alloc(), which is not called by dm-raid. So dm-raid fails when md_write_start() is called. Move the initialization to the personality modules that need it. This way it is always initialised when needed, but isn't unnecessarily initialized (requiring memory allocation) when the personality doesn't use writes_pending. Reported-by: Heinz Mauelshagen <heinzm@redhat.com> Fixes: 4ad23a976413 ("MD: use per-cpu counter for writes_pending") Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-05-24md: report sector of stripes with check mismatchesNix1-4/+14
This makes it possible, with appropriate filesystem support, for a sysadmin to tell what is affected by the mismatch, and whether it should be ignored (if it's inside a swap partition, for instance). We ratelimit to prevent log flooding: if there are so many mismatches that ratelimiting is necessary, the individual messages are relatively unlikely to be important (either the machine is swapping like crazy or something is very wrong with the disk). Signed-off-by: Nick Alcock <nick.alcock@oracle.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-05-11md/r5cache: handle sync with data in write back cacheSong Liu1-6/+15
Currently, sync of raid456 array cannot make progress when hitting data in writeback r5cache. This patch fixes this issue by flushing cached data of the stripe before processing the sync request. This is achived by: 1. In handle_stripe(), do not set STRIPE_SYNCING if the stripe is in write back cache; 2. In r5c_try_caching_write(), handle the stripe in sync with write through; 3. In do_release_stripe(), make stripe in sync write out and send it to the state machine. Shaohua: explictly set STRIPE_HANDLE after write out completed Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-05-11md/r5cache: gracefully handle journal device errors for writeback modeSong Liu1-6/+23
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>
2017-05-08md: don't return -EAGAIN in md_allow_write for external metadata arraysArtur Paszkiewicz1-9/+3
This essentially reverts commit b5470dc5fc18 ("md: resolve external metadata handling deadlock in md_allow_write") with some adjustments. Since commit 6791875e2e53 ("md: make reconfig_mutex optional for writes to md sysfs files.") changing array_state to 'active' does not use mddev_lock() and will not cause a deadlock with md_allow_write(). This revert simplifies userspace tools that write to sysfs attributes like "stripe_cache_size" or "consistency_policy" because it removes the need for special handling for external metadata arrays, checking for EAGAIN and retrying the write. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-05-04md/raid5: make use of spin_lock_irq over local_irq_disable + spin_lockJulia Cartwright1-10/+7
On mainline, there is no functional difference, just less code, and symmetric lock/unlock paths. On PREEMPT_RT builds, this fixes the following warning, seen by Alexander GQ Gerasiov, due to the sleeping nature of spinlocks. BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:993 in_atomic(): 0, irqs_disabled(): 1, pid: 58, name: kworker/u12:1 CPU: 5 PID: 58 Comm: kworker/u12:1 Tainted: G W 4.9.20-rt16-stand6-686 #1 Hardware name: Supermicro SYS-5027R-WRF/X9SRW-F, BIOS 3.2a 10/28/2015 Workqueue: writeback wb_workfn (flush-253:0) Call Trace: dump_stack+0x47/0x68 ? migrate_enable+0x4a/0xf0 ___might_sleep+0x101/0x180 rt_spin_lock+0x17/0x40 add_stripe_bio+0x4e3/0x6c0 [raid456] ? preempt_count_add+0x42/0xb0 raid5_make_request+0x737/0xdd0 [raid456] Reported-by: Alexander GQ Gerasiov <gq@redlab-i.ru> Tested-by: Alexander GQ Gerasiov <gq@redlab-i.ru> Signed-off-by: Julia Cartwright <julia@ni.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-05-01Merge branch 'md-next' into md-linusShaohua Li1-234/+409
2017-04-25md: clear WantReplacement once disk is removedGuoqing Jiang1-6/+3
We can clear 'WantReplacement' flag directly no matter it's replacement existed or not since the semantic is same as before. Also since the disk is removed from array, then it is straightforward to remove 'WantReplacement' flag and the comments in raid10/5 can be removed as well. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-04-11md/raid5: make chunk_aligned_read() split bios more cleanly.NeilBrown1-16/+17
chunk_aligned_read() currently uses fs_bio_set - which is meant for filesystems to use - and loops if multiple splits are needed, which is not best practice. As this is only used for READ requests, not writes, it is unlikely to cause a problem. However it is best to be consistent in how we split bios, and to follow the pattern used in raid1/raid10. So create a private bioset, bio_split, and use it to perform a single split, submitting the remainder to generic_make_request() for later processing. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-04-10raid5-ppl: partial parity calculation optimizationArtur Paszkiewicz1-3/+3
In case of read-modify-write, partial partity is the same as the result of ops_run_prexor5(), so we can just copy sh->dev[pd_idx].page into sh->ppl_page instead of calculating it again. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-04-10raid5-ppl: use resize_stripes() when enabling or disabling pplArtur Paszkiewicz1-50/+38
Use resize_stripes() instead of raid5_reset_stripe_cache() to allocate or free sh->ppl_page at runtime for all stripes in the stripe cache. raid5_reset_stripe_cache() required suspending the mddev and could deadlock because of GFP_KERNEL allocations. Move the 'newsize' check to check_reshape() to allow reallocating the stripes with the same number of disks. Allocate sh->ppl_page in alloc_stripe() instead of grow_buffers(). Pass 'struct r5conf *conf' as a parameter to alloc_stripe() because it is needed to check whether to allocate ppl_page. Add free_stripe() and use it to free stripes rather than directly call kmem_cache_free(). Also free sh->ppl_page in free_stripe(). Set MD_HAS_PPL at the end of ppl_init_log() instead of explicitly setting it in advance and add another parameter to log_init() to allow calling ppl_init_log() without the bit set. Don't try to calculate partial parity or add a stripe to log if it does not have ppl_page set. Enabling ppl can now be performed without suspending the mddev, because the log won't be used until new stripes are allocated with ppl_page. Calling mddev_suspend/resume is still necessary when disabling ppl, because we want all stripes to finish before stopping the log, but resize_stripes() can be called after mddev_resume() when ppl is no longer active. Suggested-by: NeilBrown <neilb@suse.com> Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-04-10md/raid6: Fix anomily when recovering a single device in RAID6.NeilBrown1-1/+12
When recoverying a single missing/failed device in a RAID6, those stripes where the Q block is on the missing device are handled a bit differently. In these cases it is easy to check that the P block is correct, so we do. This results in the P block be destroy. Consequently the P block needs to be read a second time in order to compute Q. This causes lots of seeks and hurts performance. It shouldn't be necessary to re-read P as it can be computed from the DATA. But we only compute blocks on missing devices, since c337869d9501 ("md: do not compute parity unless it is on a failed drive"). So relax the change made in that commit to allow computing of the P block in a RAID6 which it is the only missing that block. This makes RAID6 recovery run much faster as the disk just "before" the recovering device is no longer seeking back-and-forth. Reported-by-tested-by: Brad Campbell <lists2009@fnarfbargle.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-04-10md: update slab_cache before releasing new stripes when stripes resizingDennis Yang1-2/+4
When growing raid5 device on machine with small memory, there is chance that mdadm will be killed and the following bug report can be observed. The same bug could also be reproduced in linux-4.10.6. [57600.075774] BUG: unable to handle kernel NULL pointer dereference at (null) [57600.083796] IP: [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20 [57600.110378] PGD 421cf067 PUD 4442d067 PMD 0 [57600.114678] Oops: 0002 [#1] SMP [57600.180799] CPU: 1 PID: 25990 Comm: mdadm Tainted: P O 4.2.8 #1 [57600.187849] Hardware name: To be filled by O.E.M. To be filled by O.E.M./MAHOBAY, BIOS QV05AR66 03/06/2013 [57600.197490] task: ffff880044e47240 ti: ffff880043070000 task.ti: ffff880043070000 [57600.204963] RIP: 0010:[<ffffffff81a6aa87>] [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20 [57600.213057] RSP: 0018:ffff880043073810 EFLAGS: 00010046 [57600.218359] RAX: 0000000000000000 RBX: 000000000000000c RCX: ffff88011e296dd0 [57600.225486] RDX: 0000000000000001 RSI: ffffe8ffffcb46c0 RDI: 0000000000000000 [57600.232613] RBP: ffff880043073878 R08: ffff88011e5f8170 R09: 0000000000000282 [57600.239739] R10: 0000000000000005 R11: 28f5c28f5c28f5c3 R12: ffff880043073838 [57600.246872] R13: ffffe8ffffcb46c0 R14: 0000000000000000 R15: ffff8800b9706a00 [57600.253999] FS: 00007f576106c700(0000) GS:ffff88011e280000(0000) knlGS:0000000000000000 [57600.262078] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [57600.267817] CR2: 0000000000000000 CR3: 00000000428fe000 CR4: 00000000001406e0 [57600.274942] Stack: [57600.276949] ffffffff8114ee35 ffff880043073868 0000000000000282 000000000000eb3f [57600.284383] ffffffff81119043 ffff880043073838 ffff880043073838 ffff88003e197b98 [57600.291820] ffffe8ffffcb46c0 ffff88003e197360 0000000000000286 ffff880043073968 [57600.299254] Call Trace: [57600.301698] [<ffffffff8114ee35>] ? cache_flusharray+0x35/0xe0 [57600.307523] [<ffffffff81119043>] ? __page_cache_release+0x23/0x110 [57600.313779] [<ffffffff8114eb53>] kmem_cache_free+0x63/0xc0 [57600.319344] [<ffffffff81579942>] drop_one_stripe+0x62/0x90 [57600.324915] [<ffffffff81579b5b>] raid5_cache_scan+0x8b/0xb0 [57600.330563] [<ffffffff8111b98a>] shrink_slab.part.36+0x19a/0x250 [57600.336650] [<ffffffff8111e38c>] shrink_zone+0x23c/0x250 [57600.342039] [<ffffffff8111e4f3>] do_try_to_free_pages+0x153/0x420 [57600.348210] [<ffffffff8111e851>] try_to_free_pages+0x91/0xa0 [57600.353959] [<ffffffff811145b1>] __alloc_pages_nodemask+0x4d1/0x8b0 [57600.360303] [<ffffffff8157a30b>] check_reshape+0x62b/0x770 [57600.365866] [<ffffffff8157a4a5>] raid5_check_reshape+0x55/0xa0 [57600.371778] [<ffffffff81583df7>] update_raid_disks+0xc7/0x110 [57600.377604] [<ffffffff81592b73>] md_ioctl+0xd83/0x1b10 [57600.382827] [<ffffffff81385380>] blkdev_ioctl+0x170/0x690 [57600.388307] [<ffffffff81195238>] block_ioctl+0x38/0x40 [57600.393525] [<ffffffff811731c5>] do_vfs_ioctl+0x2b5/0x480 [57600.399010] [<ffffffff8115e07b>] ? vfs_write+0x14b/0x1f0 [57600.404400] [<ffffffff811733cc>] SyS_ioctl+0x3c/0x70 [57600.409447] [<ffffffff81a6ad97>] entry_SYSCALL_64_fastpath+0x12/0x6a [57600.415875] Code: 00 00 00 00 55 48 89 e5 8b 07 85 c0 74 04 31 c0 5d c3 ba 01 00 00 00 f0 0f b1 17 85 c0 75 ef b0 01 5d c3 90 31 c0 ba 01 00 00 00 <f0> 0f b1 17 85 c0 75 01 c3 55 89 c6 48 89 e5 e8 85 d1 63 ff 5d [57600.435460] RIP [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20 [57600.441208] RSP <ffff880043073810> [57600.444690] CR2: 0000000000000000 [57600.448000] ---[ end trace cbc6b5cc4bf9831d ]--- The problem is that resize_stripes() releases new stripe_heads before assigning new slab cache to conf->slab_cache. If the shrinker function raid5_cache_scan() gets called after resize_stripes() starting releasing new stripes but right before new slab cache being assigned, it is possible that these new stripe_heads will be freed with the old slab_cache which was already been destoryed and that triggers this bug. Signed-off-by: Dennis Yang <dennisyang@qnap.com> Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.") Cc: stable@vger.kernel.org (4.1+) Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-04-08block: remove the discard_zeroes_data flagChristoph Hellwig1-34/+16
Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can kill this hack. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-08md: support REQ_OP_WRITE_ZEROESChristoph Hellwig1-0/+1
Copy & paste from the REQ_OP_WRITE_SAME code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-07block: trace completion of all bios.NeilBrown1-2/+0
Currently only dm and md/raid5 bios trigger trace_block_bio_complete(). Now that we have bio_chain() and bio_inc_remaining(), it is not possible, in general, for a driver to know when the bio is really complete. Only bio_endio() knows that. So move the trace_block_bio_complete() call to bio_endio(). Now trace_block_bio_complete() pairs with trace_block_bio_queue(). Any bio for which a 'queue' event is traced, will subsequently generate a 'complete' event. There are a few cases where completion tracing is not wanted. 1/ If blk_update_request() has already generated a completion trace event at the 'request' level, there is no point generating one at the bio level too. In this case the bi_sector and bi_size will have changed, so the bio level event would be wrong 2/ If the bio hasn't actually been queued yet, but is being aborted early, then a trace event could be confusing. Some filesystems call bio_endio() but do not want tracing. 3/ The bio_integrity code interposes itself by replacing bi_end_io, then restoring it and calling bio_endio() again. This would produce two identical trace events if left like that. To handle these, we introduce a flag BIO_TRACE_COMPLETION and only produce the trace event when this is set. We address point 1 above by clearing the flag in blk_update_request(). We address point 2 above by only setting the flag when generic_make_request() is called. We address point 3 above by clearing the flag after generating a completion event. When bio_split() is used on a bio, particularly in blk_queue_split(), there is an extra complication. A new bio is split off the front, and may be handle directly without going through generic_make_request(). The old bio, which has been advanced, is passed to generic_make_request(), so it will trigger a trace event a second time. Probably the best result when a split happens is to see a single 'queue' event for the whole bio, then multiple 'complete' events - one for each component. To achieve this was can: - copy the BIO_TRACE_COMPLETION flag to the new bio in bio_split() - avoid generating a 'queue' event if BIO_TRACE_COMPLETION is already set. This way, the split-off bio won't create a queue event, the original won't either even if it re-submitted to generic_make_request(), but both will produce completion events, each for their own range. So if generic_make_request() is called (which generates a QUEUED event), then bi_endio() will create a single COMPLETE event for each range that the bio is split into, unless the driver has explicitly requested it not to. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-27md/raid5: use consistency_policy to remove journal featureSong Liu1-10/+36
When journal device of an array fails, the array is forced into read-only mode. To make the array normal without adding another journal device, we need to remove journal _feature_ from the array. This patch allows remove journal _feature_ from an array, For journal existing journal should be either missing or faulty. To remove journal feature, it is necessary to remove the journal device first: mdadm --fail /dev/md0 /dev/sdb mdadm: set /dev/sdb faulty in /dev/md0 mdadm --remove /dev/md0 /dev/sdb mdadm: hot removed /dev/sdb from /dev/md0 Then the journal feature can be removed by echoing into the sysfs file: cat /sys/block/md0/md/consistency_policy journal echo resync > /sys/block/md0/md/consistency_policy cat /sys/block/md0/md/consistency_policy resync Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-23md: fix several trivial typos in commentsZhilong Liu1-3/+3
Signed-off-by: Zhilong Liu <zlliu@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-22md/raid5: don't test ->writes_pending in raid5_remove_diskNeilBrown1-1/+4
This test on ->writes_pending cannot be safe as the counter can be incremented at any moment and cannot be locked against. Change it to test conf->active_stripes, which at least can be locked against. More changes are still needed. A future patch will change ->writes_pending, and testing it here will be very inconvenient. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-22Revert "md/raid5: limit request size according to implementation limits"NeilBrown1-9/+0
This reverts commit e8d7c33232e5fdfa761c3416539bc5b4acd12db5. Now that raid5 doesn't abuse bi_phys_segments any more, we no longer need to impose these limits. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-22md/raid5: remove over-loading of ->bi_phys_segments.NeilBrown1-12/+12
When a read request, which bypassed the cache, fails, we need to retry it through the cache. This involves attaching it to a sequence of stripe_heads, and it may not be possible to get all the stripe_heads we need at once. We do what we can, and record how far we got in ->bi_phys_segments so we can pick up again later. There is only ever one bio which may have a non-zero offset stored in ->bi_phys_segments, the one that is either active in the single thread which calls retry_aligned_read(), or is in conf->retry_read_aligned waiting for retry_aligned_read() to be called again. So we only need to store one offset value. This can be in a local variable passed between remove_bio_from_retry() and retry_aligned_read(), or in the r5conf structure next to the ->retry_read_aligned pointer. Storing it there allows the last usage of ->bi_phys_segments to be removed from md/raid5.c. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>