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2017-02-21Merge tag 'dm-4.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dmLinus Torvalds16-227/+854
Pull device mapper updates from Mike Snitzer: - Fix dm-raid transient device failure processing and other smaller tweaks. - Add journal support to the DM raid target to close the 'write hole' on raid 4/5/6. - Fix dm-cache corruption, due to rounding bug, when cache exceeds 2TB. - Add 'metadata2' feature to dm-cache to separate the dirty bitset out from other cache metadata. This improves speed of shutting down a large cache device (which implies writing out dirty bits). - Fix a memory leak during dm-stats data structure destruction. - Fix a DM multipath round-robin path selector performance regression that was caused by less precise balancing across all paths. - Lastly, introduce a DM core fix for a long-standing DM snapshot deadlock that is rooted in the complexity of the device stack used in conjunction with block core maintaining bios on current->bio_list to manage recursion in generic_make_request(). A more comprehensive fix to block core (and its hook in the cpu scheduler) would be wonderful but this DM-specific fix is pragmatic considering how difficult it has been to make progress on a generic fix. * tag 'dm-4.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (22 commits) dm: flush queued bios when process blocks to avoid deadlock dm round robin: revert "use percpu 'repeat_count' and 'current_path'" dm stats: fix a leaked s->histogram_boundaries array dm space map metadata: constify dm_space_map structures dm cache metadata: use cursor api in blocks_are_clean_separate_dirty() dm persistent data: add cursor skip functions to the cursor APIs dm cache metadata: use dm_bitset_new() to create the dirty bitset in format 2 dm bitset: add dm_bitset_new() dm cache metadata: name the cache block that couldn't be loaded dm cache metadata: add "metadata2" feature dm cache metadata: use bitset cursor api to load discard bitset dm bitset: introduce cursor api dm btree: use GFP_NOFS in dm_btree_del() dm space map common: memcpy the disk root to ensure it's arch aligned dm block manager: add unlikely() annotations on dm_bufio error paths dm cache: fix corruption seen when using cache > 2TB dm raid: cleanup awkward branching in raid_message() option processing dm raid: use mddev rather than rdev->mddev dm raid: use read_disk_sb() throughout dm raid: add raid4/5/6 journaling support ...
2017-02-21Merge tag 'for-4.11/linus-merge-signed' of git://git.kernel.dk/linux-blockLinus Torvalds20-423/+142
Pull block layer updates from Jens Axboe: - blk-mq scheduling framework from me and Omar, with a port of the deadline scheduler for this framework. A port of BFQ from Paolo is in the works, and should be ready for 4.12. - Various fixups and improvements to the above scheduling framework from Omar, Paolo, Bart, me, others. - Cleanup of the exported sysfs blk-mq data into debugfs, from Omar. This allows us to export more information that helps debug hangs or performance issues, without cluttering or abusing the sysfs API. - Fixes for the sbitmap code, the scalable bitmap code that was migrated from blk-mq, from Omar. - Removal of the BLOCK_PC support in struct request, and refactoring of carrying SCSI payloads in the block layer. This cleans up the code nicely, and enables us to kill the SCSI specific parts of struct request, shrinking it down nicely. From Christoph mainly, with help from Hannes. - Support for ranged discard requests and discard merging, also from Christoph. - Support for OPAL in the block layer, and for NVMe as well. Mainly from Scott Bauer, with fixes/updates from various others folks. - Error code fixup for gdrom from Christophe. - cciss pci irq allocation cleanup from Christoph. - Making the cdrom device operations read only, from Kees Cook. - Fixes for duplicate bdi registrations and bdi/queue life time problems from Jan and Dan. - Set of fixes and updates for lightnvm, from Matias and Javier. - A few fixes for nbd from Josef, using idr to name devices and a workqueue deadlock fix on receive. Also marks Josef as the current maintainer of nbd. - Fix from Josef, overwriting queue settings when the number of hardware queues is updated for a blk-mq device. - NVMe fix from Keith, ensuring that we don't repeatedly mark and IO aborted, if we didn't end up aborting it. - SG gap merging fix from Ming Lei for block. - Loop fix also from Ming, fixing a race and crash between setting loop status and IO. - Two block race fixes from Tahsin, fixing request list iteration and fixing a race between device registration and udev device add notifiations. - Double free fix from cgroup writeback, from Tejun. - Another double free fix in blkcg, from Hou Tao. - Partition overflow fix for EFI from Alden Tondettar. * tag 'for-4.11/linus-merge-signed' of git://git.kernel.dk/linux-block: (156 commits) nvme: Check for Security send/recv support before issuing commands. block/sed-opal: allocate struct opal_dev dynamically block/sed-opal: tone down not supported warnings block: don't defer flushes on blk-mq + scheduling blk-mq-sched: ask scheduler for work, if we failed dispatching leftovers blk-mq: don't special case flush inserts for blk-mq-sched blk-mq-sched: don't add flushes to the head of requeue queue blk-mq: have blk_mq_dispatch_rq_list() return if we queued IO or not block: do not allow updates through sysfs until registration completes lightnvm: set default lun range when no luns are specified lightnvm: fix off-by-one error on target initialization Maintainers: Modify SED list from nvme to block Move stack parameters for sed_ioctl to prevent oversized stack with CONFIG_KASAN uapi: sed-opal fix IOW for activate lsp to use correct struct cdrom: Make device operations read-only elevator: fix loading wrong elevator type for blk-mq devices cciss: switch to pci_irq_alloc_vectors block/loop: fix race between I/O and set_status blk-mq-sched: don't hold queue_lock when calling exit_icq block: set make_request_fn manually in blk_mq_update_nr_hw_queues ...
2017-02-20Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds3-5/+5
Pull locking updates from Ingo Molnar: "The main changes in this cycle were: - Implement wraparound-safe refcount_t and kref_t types based on generic atomic primitives (Peter Zijlstra) - Improve and fix the ww_mutex code (Nicolai Hähnle) - Add self-tests to the ww_mutex code (Chris Wilson) - Optimize percpu-rwsems with the 'rcuwait' mechanism (Davidlohr Bueso) - Micro-optimize the current-task logic all around the core kernel (Davidlohr Bueso) - Tidy up after recent optimizations: remove stale code and APIs, clean up the code (Waiman Long) - ... plus misc fixes, updates and cleanups" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) fork: Fix task_struct alignment locking/spinlock/debug: Remove spinlock lockup detection code lockdep: Fix incorrect condition to print bug msgs for MAX_LOCKDEP_CHAIN_HLOCKS lkdtm: Convert to refcount_t testing kref: Implement 'struct kref' using refcount_t refcount_t: Introduce a special purpose refcount type sched/wake_q: Clarify queue reinit comment sched/wait, rcuwait: Fix typo in comment locking/mutex: Fix lockdep_assert_held() fail locking/rtmutex: Flip unlikely() branch to likely() in __rt_mutex_slowlock() locking/rwsem: Reinit wake_q after use locking/rwsem: Remove unnecessary atomic_long_t casts jump_labels: Move header guard #endif down where it belongs locking/atomic, kref: Implement kref_put_lock() locking/ww_mutex: Turn off __must_check for now locking/atomic, kref: Avoid more abuse locking/atomic, kref: Use kref_get_unless_zero() more locking/atomic, kref: Kill kref_sub() locking/atomic, kref: Add kref_read() locking/atomic, kref: Add KREF_INIT() ...
2017-02-17Merge branch 'for-4.11/next' into for-4.11/linus-mergeJens Axboe20-404/+133
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-17Merge branch 'for-4.11/block' into for-4.11/linus-mergeJens Axboe3-19/+9
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-17dm: flush queued bios when process blocks to avoid deadlockMikulas Patocka1-0/+55
Commit df2cb6daa4 ("block: Avoid deadlocks with bio allocation by stacking drivers") created a workqueue for every bio set and code in bio_alloc_bioset() that tries to resolve some low-memory deadlocks by redirecting bios queued on current->bio_list to the workqueue if the system is low on memory. However other deadlocks (see below **) may happen, without any low memory condition, because generic_make_request is queuing bios to current->bio_list (rather than submitting them). ** the related dm-snapshot deadlock is detailed here: https://www.redhat.com/archives/dm-devel/2016-July/msg00065.html Fix this deadlock by redirecting any bios on current->bio_list to the bio_set's rescue workqueue on every schedule() call. Consequently, when the process blocks on a mutex, the bios queued on current->bio_list are dispatched to independent workqueus and they can complete without waiting for the mutex to be available. The structure blk_plug contains an entry cb_list and this list can contain arbitrary callback functions that are called when the process blocks. To implement this fix DM (ab)uses the onstack plug's cb_list interface to get its flush_current_bio_list() called at schedule() time. This fixes the snapshot deadlock - if the map method blocks, flush_current_bio_list() will be called and it redirects bios waiting on current->bio_list to appropriate workqueues. Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1267650 Depends-on: df2cb6daa4 ("block: Avoid deadlocks with bio allocation by stacking drivers") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-17dm round robin: revert "use percpu 'repeat_count' and 'current_path'"Mike Snitzer1-53/+14
The sloppy nature of lockless access to percpu pointers (s->current_path) in rr_select_path(), from multiple threads, is causing some paths to used more than others -- which results in less IO performance being observed. Revert these upstream commits to restore truly symmetric round-robin IO submission in DM multipath: b0b477c dm round robin: use percpu 'repeat_count' and 'current_path' 802934b dm round robin: do not use this_cpu_ptr() without having preemption disabled There is no benefit to all this complexity if repeat_count = 1 (which is the recommended default). Cc: stable@vger.kernel.org # 4.6+ Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm stats: fix a leaked s->histogram_boundaries arrayMikulas Patocka1-0/+1
Fixes: dfcfac3e4cd9 ("dm stats: collect and report histogram of IO latencies") Cc: stable@vger.kernel.org # v4.2+ Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm space map metadata: constify dm_space_map structuresBhumika Goyal1-2/+2
Declare dm_space_map structures as const as they are only passed as an argument to the function memcpy. This argument is of type const void *, so dm_space_map structures having this property can be declared as const. File size before: text data bss dec hex filename 4889 240 0 5129 1409 dm-space-map-metadata.o File size after: text data bss dec hex filename 5139 0 0 5139 1413 dm-space-map-metadata.o Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm cache metadata: use cursor api in blocks_are_clean_separate_dirty()Mike Snitzer1-7/+26
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm persistent data: add cursor skip functions to the cursor APIsJoe Thornber6-0/+70
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm cache metadata: use dm_bitset_new() to create the dirty bitset in format 2Joe Thornber1-11/+11
Big speed up with large configs. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm bitset: add dm_bitset_new()Joe Thornber2-0/+58
A more efficient way of creating a populated bitset. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm cache metadata: name the cache block that couldn't be loadedMike Snitzer1-4/+8
Improves __load_mapping_v1() and __load_mapping_v2() DMERR messages to explicitly name the cache block number whose mapping couldn't be loaded. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm cache metadata: add "metadata2" featureJoe Thornber3-53/+274
If "metadata2" is provided as a table argument when creating/loading a cache target a more compact metadata format, with separate dirty bits, is used. "metadata2" improves speed of shutting down a cache target. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm cache metadata: use bitset cursor api to load discard bitsetJoe Thornber1-20/+28
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm bitset: introduce cursor apiJoe Thornber2-0/+91
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm btree: use GFP_NOFS in dm_btree_del()Joe Thornber1-1/+6
dm_btree_del() is called from an ioctl so don't recurse into FS. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm space map common: memcpy the disk root to ensure it's arch alignedJoe Thornber1-5/+11
The metadata_space_map_root passed to sm_ll_open_metadata() may or may not be arch aligned, use memcpy to ensure it is. This is not a fast path so the extra memcpy doesn't hurt us. Long-term it'd be better to use the kernel's alignment infrastructure to remove the memcpy()s that are littered across persistent-data (btree, array, space-maps, etc). Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm block manager: add unlikely() annotations on dm_bufio error pathsJoe Thornber1-4/+4
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-16dm cache: fix corruption seen when using cache > 2TBJoe Thornber1-3/+3
A rounding bug due to compiler generated temporary being 32bit was found in remap_to_cache(). A localized cast in remap_to_cache() fixes the corruption but this preferred fix (changing from uint32_t to sector_t) eliminates potential for future rounding errors elsewhere. Cc: stable@vger.kernel.org Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-04dm: don't allow ioctls to targets that don't map to whole devicesChristoph Hellwig1-5/+8
.. at least for unprivileged users. Before we called into the SCSI ioctl code to allow excemptions for a few SCSI passthrough ioctls, but this is pretty unsafe and except for this call dm knows nothing about SCSI ioctls. As the SCSI ioctl code is now optional, we really don't want to drag it in for DM, and the exception is not very useful anyway. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Johannes Thumshirn <jthumshirn@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-03dm crypt: replace RCU read-side section with rwsemOndrej Kozina1-4/+4
The lockdep splat below hints at a bug in RCU usage in dm-crypt that was introduced with commit c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service"). The kernel keyring function user_key_payload() is in fact a wrapper for rcu_dereference_protected() which must not be called with only rcu_read_lock() section mark. Unfortunately the kernel keyring subsystem doesn't currently provide an interface that allows the use of an RCU read-side section. So for now we must drop RCU in favour of rwsem until a proper function is made available in the kernel keyring subsystem. =============================== [ INFO: suspicious RCU usage. ] 4.10.0-rc5 #2 Not tainted ------------------------------- ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by cryptsetup/6464: #0: (&md->type_lock){+.+.+.}, at: [<ffffffffa02472a2>] dm_lock_md_type+0x12/0x20 [dm_mod] #1: (rcu_read_lock){......}, at: [<ffffffffa02822f8>] crypt_set_key+0x1d8/0x4b0 [dm_crypt] stack backtrace: CPU: 1 PID: 6464 Comm: cryptsetup Not tainted 4.10.0-rc5 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014 Call Trace: dump_stack+0x67/0x92 lockdep_rcu_suspicious+0xc5/0x100 crypt_set_key+0x351/0x4b0 [dm_crypt] ? crypt_set_key+0x1d8/0x4b0 [dm_crypt] crypt_ctr+0x341/0xa53 [dm_crypt] dm_table_add_target+0x147/0x330 [dm_mod] table_load+0x111/0x350 [dm_mod] ? retrieve_status+0x1c0/0x1c0 [dm_mod] ctl_ioctl+0x1f5/0x510 [dm_mod] dm_ctl_ioctl+0xe/0x20 [dm_mod] do_vfs_ioctl+0x8e/0x690 ? ____fput+0x9/0x10 ? task_work_run+0x7e/0xa0 ? trace_hardirqs_on_caller+0x122/0x1b0 SyS_ioctl+0x3c/0x70 entry_SYSCALL_64_fastpath+0x18/0xad RIP: 0033:0x7f392c9a4ec7 RSP: 002b:00007ffef6383378 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffef63830a0 RCX: 00007f392c9a4ec7 RDX: 000000000124fcc0 RSI: 00000000c138fd09 RDI: 0000000000000005 RBP: 00007ffef6383090 R08: 00000000ffffffff R09: 00000000012482b0 R10: 2a28205d34383336 R11: 0000000000000246 R12: 00007f392d803a08 R13: 00007ffef63831e0 R14: 0000000000000000 R15: 00007f392d803a0b Fixes: c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service") Reported-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Ondrej Kozina <okozina@redhat.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-03dm rq: cope with DM device destruction while in dm_old_request_fn()Mike Snitzer1-0/+4
Fixes a crash in dm_table_find_target() due to a NULL struct dm_table being passed from dm_old_request_fn() that races with DM device destruction. Reported-by: artem@flashgrid.io Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2017-02-03dm mpath: cleanup -Wbool-operation warning in choose_pgpath()Mike Snitzer1-2/+2
Reported-by: David Binderman <dcb314@hotmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-02block: Use pointer to backing_dev_info from request_queueJan Kara14-37/+37
We will want to have struct backing_dev_info allocated separately from struct request_queue. As the first step add pointer to backing_dev_info to request_queue and convert all users touching it. No functional changes in this patch. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27dm: always defer request allocation to the owner of the request_queueChristoph Hellwig7-341/+85
DM already calls blk_mq_alloc_request on the request_queue of the underlying device if it is a blk-mq device. But now that we allow drivers to allocate additional data and initialize it ahead of time we need to do the same for all drivers. Doing so and using the new cmd_size infrastructure in the block layer greatly simplifies the dm-rq and mpath code, and should also make arbitrary combinations of SQ and MQ devices with SQ or MQ device mapper tables easily possible as a further step. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27dm: remove incomplete BLOCK_PC supportChristoph Hellwig1-16/+0
DM tries to copy a few fields around for BLOCK_PC requests, but given that no dm-target ever wires up scsi_cmd_ioctl BLOCK_PC can't actually be sent to dm. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27block: simplify blk_init_allocated_queueChristoph Hellwig1-1/+2
Return an errno value instead of the passed in queue so that the callers don't have to keep track of two queues, and move the assignment of the request_fn and lock to the caller as passing them as argument doesn't simplify anything. While we're at it also remove two pointless NULL assignments, given that the request structure is zeroed on allocation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27md: cleanup bio op / flags handling in raid1_write_requestChristoph Hellwig1-5/+2
No need for the local variables, the bio is still live and we can just assign the bits we want directly. Make me wonder why we can't assign all the bio flags to start with. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27Merge branch 'for-4.11/block' into for-4.11/rq-refactorJens Axboe3-19/+9
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27block: add a op_is_flush helperChristoph Hellwig3-19/+9
This centralizes the checks for bios that needs to be go into the flush state machine. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-25dm raid: cleanup awkward branching in raid_message() option processingMike Snitzer1-3/+4
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-25dm raid: use mddev rather than rdev->mddevHeinz Mauelshagen1-1/+1
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-25dm raid: use read_disk_sb() throughoutHeinz Mauelshagen1-8/+9
For consistency, call read_disk_sb() from attempt_restore_of_faulty_devices() instead of calling sync_page_io() directly. Explicitly set device to faulty on superblock read error. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-25dm raid: add raid4/5/6 journaling supportHeinz Mauelshagen1-21/+140
Add md raid4/5/6 journaling support (upstream commit bac624f3f86a started the implementation) which closes the write hole (i.e. non-atomic updates to stripes) using a dedicated journal device. Background: raid4/5/6 stripes hold N data payloads per stripe plus one parity raid4/5 or two raid6 P/Q syndrome payloads in an in-memory stripe cache. Parity or P/Q syndromes used to recover any data payloads in case of a disk failure are calculated from the N data payloads and need to be updated on the different component devices of the raid device. Those are non-atomic, persistent updates. Hence a crash can cause failure to update all stripe payloads persistently and thus cause data loss during stripe recovery. This problem gets addressed by writing whole stripe cache entries (together with journal metadata) to a persistent journal entry on a dedicated journal device. Only if that journal entry is written successfully, the stripe cache entry is updated on the component devices of the raid device (i.e. writethrough type). In case of a crash, the entry can be recovered from the journal and be written again thus ensuring consistent stripe payload suitable to data recovery. Future dependencies: once writeback caching being worked on to compensate for the throughput implictions involved with writethrough overhead is supported with journaling in upstream, an additional patch based on this one will support it in dm-raid. Journal resilience related remarks: because stripes are recovered from the journal in case of a crash, the journal device better be resilient. Resilience becomes mandatory with future writeback support, because loosing the working set in the log means data loss as oposed to writethrough, were the loss of the journal device 'only' reintroduces the write hole. Fix comment on data offsets in parse_dev_params() and initialize new_data_offset as well. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-25dm raid: be prepared to accept arbitrary '- -' tuplesHeinz Mauelshagen1-5/+23
During raid set resize checks and setting up the recovery offset in case a raid set grows, calculated rd->md.dev_sectors is compared to rs->dev[0].rdev.sectors. Device 0 may not be defined in case userspace passes in '- -' for it (lvm2 doesn't do that so far), thus it's device sectors can't be taken authoritatively in this comparison and another valid device must be used to retrieve the device size. Use mddev->dev_sectors in checking for ongoing recovery for the same reason. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-25dm raid: fix transient device failure processingHeinz Mauelshagen1-49/+38
This fix addresses the following 3 failure scenarios: 1) If a (transiently) inaccessible metadata device is being passed into the constructor (e.g. a device tuple '254:4 254:5'), it is processed as if '- -' was given. This erroneously results in a status table line containing '- -', which mistakenly differs from what has been passed in. As a result, userspace libdevmapper puts the device tuple seperate from the RAID device thus not processing the dependencies properly. 2) False health status char 'A' instead of 'D' is emitted on the status status info line for the meta/data device tuple in this metadata device failure case. 3) If the metadata device is accessible when passed into the constructor but the data device (partially) isn't, that leg may be set faulty by the raid personality on access to the (partially) unavailable leg. Restore tried in a second raid device resume on such failed leg (status char 'D') fails after the (partial) leg returned. Fixes for aforementioned failure scenarios: - don't release passed in devices in the constructor thus allowing the status table line to e.g. contain '254:4 254:5' rather than '- -' - emit device status char 'D' rather than 'A' for the device tuple with the failed metadata device on the status info line - when attempting to restore faulty devices in a second resume, allow the device hot remove function to succeed by setting the device to not in-sync In case userspace intentionally passes '- -' into the constructor to avoid that device tuple (e.g. to split off a raid1 leg temporarily for later re-addition), the status table line will correctly show '- -' and the status info line will provide a '-' device health character for the non-defined device tuple. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-24md/r5cache: disable write back for degraded arraySong Liu3-7/+56
write-back cache in degraded mode introduces corner cases to the array. Although we try to cover all these corner cases, it is safer to just disable write-back cache when the array is in degraded mode. In this patch, we disable writeback cache for degraded mode: 1. On device failure, if the array enters degraded mode, raid5_error() will submit async job r5c_disable_writeback_async to disable writeback; 2. In r5c_journal_mode_store(), it is invalid to enable writeback in degraded mode; 3. In r5c_try_caching_write(), stripes with s->failed>0 will be handled in write-through mode. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-24md/r5cache: shift complex rmw from read path to write pathSong Liu1-4/+45
Write back cache requires a complex RMW mechanism, where old data is read into dev->orig_page for prexor, and then xor is done with dev->page. This logic is already implemented in the write path. However, current read path is not awared of this requirement. When the array is optimal, the RMW is not required, as the data are read from raid disks. However, when the target stripe is degraded, complex RMW is required to generate right data. To keep read path as clean as possible, we handle read path by flushing degraded, in-journal stripes before processing reads to missing dev. Specifically, when there is read requests to a degraded stripe with data in journal, handle_stripe_fill() calls r5c_make_stripe_write_out() and exits. Then handle_stripe_dirtying() will do the complex RMW and flush the stripe to RAID disks. After that, read requests are handled. There is one more corner case when there is non-overwrite bio for the missing (or out of sync) dev. handle_stripe_dirtying() will not be able to process the non-overwrite bios without constructing the data in handle_stripe_fill(). This is fixed by delaying non-overwrite bios in handle_stripe_dirtying(). So handle_stripe_fill() works on these bios after the stripe is flushed to raid disks. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-24md/r5cache: flush data only stripes in r5l_recovery_log()Song Liu2-16/+45
For safer operation, all arrays start in write-through mode, which has been better tested and is more mature. And actually the write-through/write-mode isn't persistent after array restarted, so we always start array in write-through mode. However, if recovery found data-only stripes before the shutdown (from previous write-back mode), it is not safe to start the array in write-through mode, as write-through mode can not handle stripes with data in write-back cache. To solve this problem, we flush all data-only stripes in r5l_recovery_log(). When r5l_recovery_log() returns, the array starts with empty cache in write-through mode. This logic is implemented in r5c_recovery_flush_data_only_stripes(): 1. enable write back cache 2. flush all stripes 3. wake up conf->mddev->thread 4. wait for all stripes get flushed (reuse wait_for_quiescent) 5. disable write back cache The wait in 4 will be waked up in release_inactive_stripe_list() when conf->active_stripes reaches 0. It is safe to wake up mddev->thread here because all the resource required for the thread has been initialized. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-24md/raid5: move comment of fetch_block to right locationSong Liu1-7/+6
Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-24md/r5cache: read data into orig_page for prexor of cached dataSong Liu3-9/+42
With write back cache, we use orig_page to do prexor. This patch makes sure we read data into orig_page for it. Flag R5_OrigPageUPTDODATE is added to show whether orig_page has the latest data from raid disk. We introduce a helper function uptodate_for_rmw() to simplify the a couple conditions in handle_stripe_dirtying(). Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-24md/raid5-cache: delete meaningless codeShaohua Li1-2/+0
sector_t is unsigned long, it's never < 0 Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-14sched/core: Remove set_task_state()Davidlohr Bueso3-5/+5
This is a nasty interface and setting the state of a foreign task must not be done. As of the following commit: be628be0956 ("bcache: Make gc wakeup sane, remove set_task_state()") ... everyone in the kernel calls set_task_state() with current, allowing the helper to be removed. However, as the comment indicates, it is still around for those archs where computing current is more expensive than using a pointer, at least in theory. An important arch that is affected is arm64, however this has been addressed now [1] and performance is up to par making no difference with either calls. Of all the callers, if any, it's the locking bits that would care most about this -- ie: we end up passing a tsk pointer to a lot of the lock slowpath, and setting ->state on that. The following numbers are based on two tests: a custom ad-hoc microbenchmark that just measures latencies (for ~65 million calls) between get_task_state() vs get_current_state(). Secondly for a higher overview, an unlink microbenchmark was used, which pounds on a single file with open, close,unlink combos with increasing thread counts (up to 4x ncpus). While the workload is quite unrealistic, it does contend a lot on the inode mutex or now rwsem. [1] https://lkml.kernel.org/r/1483468021-8237-1-git-send-email-mark.rutland@arm.com == 1. x86-64 == Avg runtime set_task_state(): 601 msecs Avg runtime set_current_state(): 552 msecs vanilla dirty Hmean unlink1-processes-2 36089.26 ( 0.00%) 38977.33 ( 8.00%) Hmean unlink1-processes-5 28555.01 ( 0.00%) 29832.55 ( 4.28%) Hmean unlink1-processes-8 37323.75 ( 0.00%) 44974.57 ( 20.50%) Hmean unlink1-processes-12 43571.88 ( 0.00%) 44283.01 ( 1.63%) Hmean unlink1-processes-21 34431.52 ( 0.00%) 38284.45 ( 11.19%) Hmean unlink1-processes-30 34813.26 ( 0.00%) 37975.17 ( 9.08%) Hmean unlink1-processes-48 37048.90 ( 0.00%) 39862.78 ( 7.59%) Hmean unlink1-processes-79 35630.01 ( 0.00%) 36855.30 ( 3.44%) Hmean unlink1-processes-110 36115.85 ( 0.00%) 39843.91 ( 10.32%) Hmean unlink1-processes-141 32546.96 ( 0.00%) 35418.52 ( 8.82%) Hmean unlink1-processes-172 34674.79 ( 0.00%) 36899.21 ( 6.42%) Hmean unlink1-processes-203 37303.11 ( 0.00%) 36393.04 ( -2.44%) Hmean unlink1-processes-224 35712.13 ( 0.00%) 36685.96 ( 2.73%) == 2. ppc64le == Avg runtime set_task_state(): 938 msecs Avg runtime set_current_state: 940 msecs vanilla dirty Hmean unlink1-processes-2 19269.19 ( 0.00%) 30704.50 ( 59.35%) Hmean unlink1-processes-5 20106.15 ( 0.00%) 21804.15 ( 8.45%) Hmean unlink1-processes-8 17496.97 ( 0.00%) 17243.28 ( -1.45%) Hmean unlink1-processes-12 14224.15 ( 0.00%) 17240.21 ( 21.20%) Hmean unlink1-processes-21 14155.66 ( 0.00%) 15681.23 ( 10.78%) Hmean unlink1-processes-30 14450.70 ( 0.00%) 15995.83 ( 10.69%) Hmean unlink1-processes-48 16945.57 ( 0.00%) 16370.42 ( -3.39%) Hmean unlink1-processes-79 15788.39 ( 0.00%) 14639.27 ( -7.28%) Hmean unlink1-processes-110 14268.48 ( 0.00%) 14377.40 ( 0.76%) Hmean unlink1-processes-141 14023.65 ( 0.00%) 16271.69 ( 16.03%) Hmean unlink1-processes-172 13417.62 ( 0.00%) 16067.55 ( 19.75%) Hmean unlink1-processes-203 15293.08 ( 0.00%) 15440.40 ( 0.96%) Hmean unlink1-processes-234 13719.32 ( 0.00%) 16190.74 ( 18.01%) Hmean unlink1-processes-265 16400.97 ( 0.00%) 16115.22 ( -1.74%) Hmean unlink1-processes-296 14388.60 ( 0.00%) 16216.13 ( 12.70%) Hmean unlink1-processes-320 15771.85 ( 0.00%) 15905.96 ( 0.85%) x86-64 (known to be fast for get_current()/this_cpu_read_stable() caching) and ppc64 (with paca) show similar improvements in the unlink microbenches. The small delta for ppc64 (2ms), does not represent the gains on the unlink runs. In the case of x86, there was a decent amount of variation in the latency runs, but always within a 20 to 50ms increase), ppc was more constant. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: mark.rutland@arm.com Link: http://lkml.kernel.org/r/1483479794-14013-5-git-send-email-dave@stgolabs.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-09md/raid5: Use correct IS_ERR() variation on pointer checkJes Sorensen1-1/+1
This fixes a build error on certain architectures, such as ppc64. Fixes: 6995f0b247e("md: takeover should clear unrelated bits") Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-05md: cleanup mddev flag clear for takeoverShaohua Li4-7/+26
Commit 6995f0b (md: takeover should clear unrelated bits) clear unrelated bits, but it's quite fragile. To avoid error in the future, define a macro for unsupported mddev flags for each raid type and use it to clear unsupported mddev flags. This should be less error-prone. Suggested-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-05md/r5cache: fix spelling mistake on "recoverying"Colin Ian King1-1/+1
Trivial fix to spelling mistake "recoverying" to "recovering" in pr_dbg message. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-05md/r5cache: assign conf->log before r5l_load_log()Song Liu1-1/+3
r5l_load_log() calls functions that requires a proper conf->log, for example, r5c_is_writeback(). Therefore, we should set conf->log before calling r5l_load_log(). If r5l_load_log() fails, conf->log is set back to NULL. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2017-01-05md/r5cache: simplify handling of sh->log_start in recoverySong Liu1-15/+12
We only need to update sh->log_start at the end of recovery, which is r5c_recovery_rewrite_data_only_stripes(), so it is not necessary to set it before that. In this patch, log_start is removed from r5c_recovery_alloc_stripe(). After updating all sh->log_start, rewrite_data_only_stripes() also updates log->next_checkpoints to the last sh->log_start. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>