summaryrefslogtreecommitdiff
path: root/drivers/md
AgeCommit message (Collapse)Author
2014-11-16Merge tag 'md/3.18-fix' of git://neil.brown.name/mdLinus Torvalds
Pull md bugfix from Neil Brown: "One fix for md for 3.18. This fixes a regression introduced in 3.13" * tag 'md/3.18-fix' of git://neil.brown.name/md: md: Always set RECOVERY_NEEDED when clearing RECOVERY_FROZEN
2014-11-17md: Always set RECOVERY_NEEDED when clearing RECOVERY_FROZENNeilBrown
md_check_recovery will skip any recovery and also clear MD_RECOVERY_NEEDED if MD_RECOVERY_FROZEN is set. So when we clear _FROZEN, we must set _NEEDED and ensure that md_check_recovery gets run. Otherwise we could miss out on something that is needed. In particular, this can make it impossible to remove a failed device from an array is the 'recovery-needed' processing didn't happen. Suitable for stable kernels since 3.13. Cc: stable@vger.kernel.org (3.13+) Reported-and-tested-by: Joe Lawrence <joe.lawrence@stratus.com> Fixes: 30b8feb730f9b9b3c5de02580897da03f59b6b16 Signed-off-by: NeilBrown <neilb@suse.de>
2014-11-13Merge tag 'dm-3.18-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper fixes from Mike Snitzer: - stable fix for dm-thin that avoids normal IO racing with discard - stable fix for a dm-cache related bug in dm-btree walking code that results from using very large fast device (eg 4T) with a very small cache blocksize (eg 32K) -- this is a very uncommon configuration - a couple fixes for dm-raid (one for stable and the other addresses a crash in 3.18-rc1 code) - stable fix for dm-thinp that addresses a very rare dm-bufio bug having to do with memory reclaimation (via shrinker) when using dm-thinp ontop of loopback devices - fix a leak in dm-stripe target constructor's error path * tag 'dm-3.18-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm btree: fix a recursion depth bug in btree walking code dm thin: grab a virtual cell before looking up the mapping dm raid: fix inaccessible superblocks causing oops in configure_discard_support dm raid: ensure superblock's size matches device's logical block size dm bufio: change __GFP_IO to __GFP_FS in shrinker callbacks dm stripe: fix potential for leak in stripe_ctr error path
2014-11-10dm btree: fix a recursion depth bug in btree walking codeJoe Thornber
The walk code was using a 'ro_spine' to hold it's locked btree nodes. But this data structure is designed for the rolling lock scheme, and as such automatically unlocks blocks that are two steps up the call chain. This is not suitable for the simple recursive walk algorithm, which retraces its steps. This code is only used by the persistent array code, which in turn is only used by dm-cache. In order to trigger it you need to have a mapping tree that is more than 2 levels deep; which equates to 8-16 million cache blocks. For instance a 4T ssd with a very small block size of 32k only just triggers this bug. The fix just places the locked blocks on the stack, and stops using the ro_spine altogether. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-11-04dm thin: grab a virtual cell before looking up the mappingJoe Thornber
Avoids normal IO racing with discard. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-10-29dm raid: fix inaccessible superblocks causing oops in configure_discard_supportHeinz Mauelshagen
Commit 48cf06bc5f ("dm raid: add discard support for RAID levels 4, 5 and 6") did not properly handle missing metadata device(s). A failing read of the superblock causes the metadata and data devices to be removed from the dev array in struct raid_set, setting references to both devices to NULL. configure_discard_support() nonetheless tries to access the data dev unconditionally causing an oops. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-21dm raid: ensure superblock's size matches device's logical block sizeHeinz Mauelshagen
The dm-raid superblock (struct dm_raid_superblock) is padded to 512 bytes and that size is being used to read it in from the metadata device into one preallocated page. Reading or writing this on a 512-byte sector device works fine but on a 4096-byte sector device this fails. Set the dm-raid superblock's size to the logical block size of the metadata device, because IO at that size is guaranteed too work. Also add a size check to avoid silent partial metadata loss in case the superblock should ever grow past the logical block size or PAGE_SIZE. [includes pointer math fix from Dan Carpenter] Reported-by: "Liuhua Wang" <lwang@suse.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-10-18Merge tag 'dm-3.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device-mapper updates from Mike Snitzer: "I rebased the DM tree ontop of linux-block.git's 'for-3.18/core' at the beginning of October because DM core now depends on the newly introduced bioset_create_nobvec() interface. Summary: - fix DM's long-standing excessive use of memory by leveraging the new bioset_create_nobvec() interface when creating the DM's bioset - fix a few bugs in dm-bufio and dm-log-userspace - add DM core support for a DM multipath use-case that requires loading DM tables that contain devices that have failed (by allowing active and inactive DM tables to share dm_devs) - add discard support to the DM raid target; like MD raid456 the user must opt-in to raid456 discard support be specifying the devices_handle_discard_safely=Y module param" * tag 'dm-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm log userspace: fix memory leak in dm_ulog_tfr_init failure path dm bufio: when done scanning return from __scan immediately dm bufio: update last_accessed when relinking a buffer dm raid: add discard support for RAID levels 4, 5 and 6 dm raid: add discard support for RAID levels 1 and 10 dm: allow active and inactive tables to share dm_devs dm mpath: stop queueing IO when no valid paths exist dm: use bioset_create_nobvec() dm: remove nr_iovecs parameter from alloc_tio()
2014-10-18Merge branch 'for-3.18/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer driver update from Jens Axboe: "This is the block driver pull request for 3.18. Not a lot in there this round, and nothing earth shattering. - A round of drbd fixes from the linbit team, and an improvement in asender performance. - Removal of deprecated (and unused) IRQF_DISABLED flag in rsxx and hd from Michael Opdenacker. - Disable entropy collection from flash devices by default, from Mike Snitzer. - A small collection of xen blkfront/back fixes from Roger Pau Monné and Vitaly Kuznetsov" * 'for-3.18/drivers' of git://git.kernel.dk/linux-block: block: disable entropy contributions for nonrot devices xen, blkfront: factor out flush-related checks from do_blkif_request() xen-blkback: fix leak on grant map error path xen/blkback: unmap all persistent grants when frontend gets disconnected rsxx: Remove deprecated IRQF_DISABLED block: hd: remove deprecated IRQF_DISABLED drbd: use RB_DECLARE_CALLBACKS() to define augment callbacks drbd: compute the end before rb_insert_augmented() drbd: Add missing newline in resync progress display in /proc/drbd drbd: reduce lock contention in drbd_worker drbd: Improve asender performance drbd: Get rid of the WORK_PENDING macro drbd: Get rid of the __no_warn and __cond_lock macros drbd: Avoid inconsistent locking warning drbd: Remove superfluous newline from "resync_extents" debugfs entry. drbd: Use consistent names for all the bi_end_io callbacks drbd: Use better variable names
2014-10-18Merge tag 'md/3.18' of git://neil.brown.name/mdLinus Torvalds
Pull md updates from Neil Brown: - a few minor bug fixes - quite a lot of code tidy-up and simplification - remove PRINT_RAID_DEBUG ioctl. I'm fairly sure it is unused, and it isn't particularly useful. * tag 'md/3.18' of git://neil.brown.name/md: (21 commits) lib/raid6: Add log level to printks md: move EXPORT_SYMBOL to after function in md.c md: discard PRINT_RAID_DEBUG ioctl md: remove MD_BUG() md: clean up 'exit' labels in md_ioctl(). md: remove unnecessary test for MD_MAJOR in md_ioctl() md: don't allow "-sync" to be set for device in an active array. md: remove unwanted white space from md.c md: don't start resync thread directly from md thread. md: Just use RCU when checking for overlap between arrays. md: avoid potential long delay under pers_lock md: simplify export_array() md: discard find_rdev_nr in favour of find_rdev_nr_rcu md: use wait_event() to simplify md_super_wait() md: be more relaxed about stopping an array which isn't started. md/raid1: process_checks doesn't use its return value. md/raid5: fix init_stripe() inconsistencies md/raid10: another memory leak due to reshape. md: use set_bit/clear_bit instead of shift/mask for bi_flags changes. md/raid1: minor typos and reformatting. ...
2014-10-17dm bufio: change __GFP_IO to __GFP_FS in shrinker callbacksMikulas Patocka
The shrinker uses gfp flags to indicate what kind of operation can the driver wait for. If __GFP_IO flag is present, the driver can wait for block I/O operations, if __GFP_FS flag is present, the driver can wait on operations involving the filesystem. dm-bufio tested for __GFP_IO. However, dm-bufio can run on a loop block device that makes calls into the filesystem. If __GFP_IO is present and __GFP_FS isn't, dm-bufio could still block on filesystem operations if it runs on a loop block device. The change from __GFP_IO to __GFP_FS supposedly fixes one observed (though unreproducible) deadlock involving dm-bufio and loop device. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-10-15Merge branch 'for-3.18-consistent-ops' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu consistent-ops changes from Tejun Heo: "Way back, before the current percpu allocator was implemented, static and dynamic percpu memory areas were allocated and handled separately and had their own accessors. The distinction has been gone for many years now; however, the now duplicate two sets of accessors remained with the pointer based ones - this_cpu_*() - evolving various other operations over time. During the process, we also accumulated other inconsistent operations. This pull request contains Christoph's patches to clean up the duplicate accessor situation. __get_cpu_var() uses are replaced with with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr(). Unfortunately, the former sometimes is tricky thanks to C being a bit messy with the distinction between lvalues and pointers, which led to a rather ugly solution for cpumask_var_t involving the introduction of this_cpu_cpumask_var_ptr(). This converts most of the uses but not all. Christoph will follow up with the remaining conversions in this merge window and hopefully remove the obsolete accessors" * 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits) irqchip: Properly fetch the per cpu offset percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write. percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t Revert "powerpc: Replace __get_cpu_var uses" percpu: Remove __this_cpu_ptr clocksource: Replace __this_cpu_ptr with raw_cpu_ptr sparc: Replace __get_cpu_var uses avr32: Replace __get_cpu_var with __this_cpu_write blackfin: Replace __get_cpu_var uses tile: Use this_cpu_ptr() for hardware counters tile: Replace __get_cpu_var uses powerpc: Replace __get_cpu_var uses alpha: Replace __get_cpu_var ia64: Replace __get_cpu_var uses s390: cio driver &__get_cpu_var replacements s390: Replace __get_cpu_var uses mips: Replace __get_cpu_var uses MIPS: Replace __get_cpu_var uses in FPU emulator. arm: Replace __this_cpu_ptr with raw_cpu_ptr ...
2014-10-14crypto, dm: LLVMLinux: Remove VLAIS usage from dm-cryptJan-Simon Möller
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99 compliant equivalent. This patch allocates the appropriate amount of memory using a char array using the SHASH_DESC_ON_STACK macro. The new code can be compiled with both gcc and clang. Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> Signed-off-by: Behan Webster <behanw@converseincode.com> Reviewed-by: Mark Charlebois <charlebm@gmail.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Cc: pageexec@freemail.hu Cc: gmazyland@gmail.com Cc: "David S. Miller" <davem@davemloft.net>
2014-10-14md: move EXPORT_SYMBOL to after function in md.cNeilBrown
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: discard PRINT_RAID_DEBUG ioctlNeilBrown
All the interesting information printed by this ioctl is provided in /proc/mdstat and/or sysfs. So it isn't needed and isn't used and would be best if it didn't exist. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: remove MD_BUG()NeilBrown
Most of the places that call this are doing so pointlessly. A couple of the others a best replaced with WARN_ON(). Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: clean up 'exit' labels in md_ioctl().NeilBrown
There are 4 labels and we only really need two. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: remove unnecessary test for MD_MAJOR in md_ioctl()NeilBrown
unknown ioctls no longer get this deep into md_ioctl since md_ioctl_valid() was introduced in 3.14. So remove the test and the misleading comment. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: don't allow "-sync" to be set for device in an active array.NeilBrown
If an array is active, devices can be marked 'faulty', but simply removing the 'sync' flag is wrong. That only makes sense for an array which is not active (and is probably only useful for testing anyway). Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: remove unwanted white space from md.cNeilBrown
My editor shows much of this is RED. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: don't start resync thread directly from md thread.NeilBrown
The main 'md' thread is needed for processing writes, so if it blocks write requests could be delayed. Starting a new thread requires some GFP_KERNEL allocations and so can wait for writes to complete. This can deadlock. So instead, ask a workqueue to start the sync thread. There is no particular rush for this to happen, so any work queue will do. MD_RECOVERY_RUNNING is used to ensure only one thread is started. Reported-by: BillStuff <billstuff2001@sbcglobal.net> Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: Just use RCU when checking for overlap between arrays.NeilBrown
We don't really need the full mddev_lock here, and having to drop it is messy. RCU is enough to protect these lists. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: avoid potential long delay under pers_lockChao Yu
printk may cause long time lapse if value of printk_delay in sysctl is configured large by user. If register_md_personality takes long time to print in spinlock pers_lock, we may encounter high CPU usage rate when there are other pers_lock competitors who may be blocked to spin. We can avoid this condition by moving printk out of coverage of pers_lock spinlock. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: simplify export_array()NeilBrown
We don't really need that for_each loop, or those MD_BUGs. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: discard find_rdev_nr in favour of find_rdev_nr_rcuNeilBrown
Having both is a waste - just use the one. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: use wait_event() to simplify md_super_wait()NeilBrown
md_super_wait is really just wait_event() open-coded. So use the macro instead. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md: be more relaxed about stopping an array which isn't started.NeilBrown
In general we don't allow an array to be stopped if it is in use. However if the array hasn't really been started yet, then any apparent use is an anomily, probably due to 'udev' or similar having a look to see what is there. This means that if something goes wrong while assembling an array it cannot reliably be un-assembled - STOP_ARRAY could fail. There is no value here, so change do_md_stop() to succeed despite concurrent opens if the array has not yet been activated. i.e. if ->pers is NULL. Reported-by: "Baldysiak, Pawel" <pawel.baldysiak@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md/raid1: process_checks doesn't use its return value.NeilBrown
process_checks() always returns '0', so change it to 'void'. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md/raid5: fix init_stripe() inconsistenciesMarkus Stockhausen
raid5: fix init_stripe() inconsistencies 1) remove_hash() is not necessary. We will only be called right after get_free_stripe(). There we have already a call to remove_hash(). 2) Tracing prints out the sector of the freed stripe and not the sector that we want to initialize. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14md/raid10: another memory leak due to reshape.NeilBrown
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-13Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave Hansen) - Various sched/idle refinements for better idle handling (Nicolas Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot) - sched/numa updates and optimizations (Rik van Riel) - sysbench speedup (Vincent Guittot) - capacity calculation cleanups/refactoring (Vincent Guittot) - Various cleanups to thread group iteration (Oleg Nesterov) - Double-rq-lock removal optimization and various refactorings (Kirill Tkhai) - various sched/deadline fixes ... and lots of other changes" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits) sched/dl: Use dl_bw_of() under rcu_read_lock_sched() sched/fair: Delete resched_cpu() from idle_balance() sched, time: Fix build error with 64 bit cputime_t on 32 bit systems sched: Improve sysbench performance by fixing spurious active migration sched/x86: Fix up typo in topology detection x86, sched: Add new topology for multi-NUMA-node CPUs sched/rt: Use resched_curr() in task_tick_rt() sched: Use rq->rd in sched_setaffinity() under RCU read lock sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask' sched: Use dl_bw_of() under RCU read lock sched/fair: Remove duplicate code from can_migrate_task() sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW sched: print_rq(): Don't use tasklist_lock sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock() sched: Fix the task-group check in tg_has_rt_tasks() sched/fair: Leverage the idle state info when choosing the "idlest" cpu sched: Let the scheduler see CPU idle states sched/deadline: Fix inter- exclusive cpusets migrations sched/deadline: Clear dl_entity params when setscheduling to different class sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault() ...
2014-10-10dm stripe: fix potential for leak in stripe_ctr error pathPavitra Kumar
Fix a potential struct stripe_c leak that would occur if the chunk_size exceeded the maximum allowed by dm_set_target_max_io_len (UINT_MAX). However, in practice there is no possibility of this occuring given that chunk_size is of type uint32_t. But it is good to fix this to future-proof in case dm_set_target_max_io_len's implementation were to change. Signed-off-by: Pavitra Kumar <pavitrak@nvidia.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-09md: use set_bit/clear_bit instead of shift/mask for bi_flags changes.NeilBrown
Using {set,clear}_bit is more consistent than shifting and masking. No functional change. Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-09md/raid1: minor typos and reformatting.NeilBrown
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-09md/bitmap: always wait for writes on unplug.NeilBrown
If two threads call bitmap_unplug at the same time, then one might schedule all the writes, and the other might decide that it doesn't need to wait. But really it does. It rarely hurts to wait when it isn't absolutely necessary, and the current code doesn't really focus on 'absolutely necessary' anyway. So just wait always. This can potentially lead to data corruption if a crash happens at an awkward time and data was written before the bitmap was updated. It is very unlikely, but this should go to -stable just to be safe. Appropriate for any -stable. Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@vger.kernel.org (please delay until 3.18 is released)
2014-10-05dm log userspace: fix memory leak in dm_ulog_tfr_init failure pathAlexey Khoroshilov
If cn_add_callback() fails in dm_ulog_tfr_init(), it does not deallocate prealloced memory but calls cn_del_callback(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Reviewed-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-10-05dm bufio: when done scanning return from __scan immediatelyMikulas Patocka
When __scan frees the required number of buffer entries that the shrinker requested (nr_to_scan becomes zero) it must return. Before this fix the __scan code exited only the inner loop and continued in the outer loop -- which could result in reduced performance due to extra buffers being freed (e.g. unnecessarily evicted thinp metadata needing to be synchronously re-read into bufio's cache). Also, move dm_bufio_cond_resched to __scan's inner loop, so that iterating the bufio client's lru lists doesn't result in scheduling latency. Reported-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 3.2+
2014-10-05dm bufio: update last_accessed when relinking a bufferJoe Thornber
The 'last_accessed' member of the dm_buffer structure was only set when the the buffer was created. This led to each buffer being discarded after dm_bufio_max_age time even if it was used recently. In practice this resulted in all thinp metadata being evicted soon after being read -- this is particularly problematic for metadata intensive workloads like multithreaded small random IO. 'last_accessed' is now updated each time the buffer is moved to the head of the LRU list, so the buffer is now properly discarded if it was not used in dm_bufio_max_age time. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # v3.2+
2014-10-05dm raid: add discard support for RAID levels 4, 5 and 6Heinz Mauelshagen
In case of RAID levels 4, 5 and 6 we have to verify each RAID members' ability to zero data on discards to avoid stripe data corruption -- if discard_zeroes_data is not set for each RAID member discard support must be disabled. But given the uncertainty of whether or not a RAID member properly supports zeroing data on discard we require the user to explicitly allow discard support on RAID levels 4, 5, and 6 by setting a dm-raid module paramter, e.g.: dm-raid.devices_handle_discard_safely=Y Otherwise, discards could cause data corruption on RAID4/5/6. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-05dm raid: add discard support for RAID levels 1 and 10Heinz Mauelshagen
Discard support is not enabled for RAID levels 4, 5, and 6 at this time due to concerns about unreliable discard_zeroes_data support on some hardware. Otherwise, discards could cause stripe data corruption (classic example of bad apples spoiling the bunch). Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-05dm: allow active and inactive tables to share dm_devsBenjamin Marzinski
Until this change, when loading a new DM table, DM core would re-open all of the devices in the DM table. Now, DM core will avoid redundant device opens (and closes when destroying the old table) if the old table already has a device open using the same mode. This is achieved by managing reference counts on the table_devices that DM core now stores in the mapped_device structure (rather than in the dm_table structure). So a mapped_device's active and inactive dm_tables' dm_dev lists now just point to the dm_devs stored in the mapped_device's table_devices list. This improvement in DM core's device reference counting has the side-effect of fixing a long-standing limitation of the multipath target: a DM multipath table couldn't include any paths that were unusable (failed). For example: if all paths have failed and you add a new, working, path to the table; you can't use it since the table load would fail due to it still containing failed paths. Now a re-load of a multipath table can include failed devices and when those devices become active again they can be used instantly. The device list code in dm.c isn't a straight copy/paste from the code in dm-table.c, but it's very close (aside from some variable renames). One subtle difference is that find_table_device for the tables_devices list will only match devices with the same name and mode. This is because we don't want to upgrade a device's mode in the active table when an inactive table is loaded. Access to the mapped_device structure's tables_devices list requires a mutex (tables_devices_lock), so that tables cannot be created and destroyed concurrently. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-05dm mpath: stop queueing IO when no valid paths existBenjamin Marzinski
'queue_io' is set so that IO is queued while paths are being initialized. Clear queue_io in __choose_pgpath if there are no valid paths, since there are obviously no paths that can be initialized. Otherwise IOs to the device will back up. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-05dm: use bioset_create_nobvec()Junichi Nomura
Since DM core uses bio_clone_fast() for both bio-based and request-based DM devices there is no need for DM's bioset to have a bvec mempool. With this patch, on arch with 4KB page for example, memory usage will be reduced by 64KB for each bio-based DM device and 1MB for each request-based DM device. For example, when you create 10,000 bio-based DM devices and 1,000 request-based DM devices, memory usage of biovec under no load is: # grep biovec /proc/slabinfo biovec-256 418068 418068 4096 ... biovec-128 0 0 2048 ... biovec-64 0 0 1024 ... biovec-16 0 0 256 ... With this patch series applied, the usage becomes: # grep biovec /proc/slabinfo biovec-256 116 116 4096 ... biovec-128 0 0 2048 ... biovec-64 0 0 1024 ... biovec-16 0 0 256 ... So 4096 * (418068 - 116) = 1.6GB of memory is saved in this example. Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-05dm: remove nr_iovecs parameter from alloc_tio()Junichi Nomura
alloc_tio() uses bio_alloc_bioset() to allocate a clone-bio for a bio. alloc_tio() takes the number of bvecs to allocate for the clone-bio. However, with v3.14's immutable biovec changes DM now uses __bio_clone_fast() and no longer needs to allocate bvecs. In practice, the 'nr_iovecs' passed to alloc_tio() is always effectively 0. __clone_and_map_simple_bio() looked like it was passing non-zero nr_iovecs, but its value was always within the range of inline bvecs and no allocation actually happened. If allocation happened, the BUG_ON() in __bio_clone_fast() would've triggered. Remove the nr_iovecs parameter from alloc_tio() to prevent possible future bio_alloc_bioset() mis-use of a new bioset interface that will no longer allow bvecs to be allocated. Also fix extra whitespace before the __bio_clone_fast() call in __clone_and_map_simple_bio(). Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-04block: disable entropy contributions for nonrot devicesMike Snitzer
Clear QUEUE_FLAG_ADD_RANDOM in all block drivers that set QUEUE_FLAG_NONROT. Historically, all block devices have automatically made entropy contributions. But as previously stated in commit e2e1a148 ("block: add sysfs knob for turning off disk entropy contributions"): - On SSD disks, the completion times aren't as random as they are for rotational drives. So it's questionable whether they should contribute to the random pool in the first place. - Calling add_disk_randomness() has a lot of overhead. There are more reliable sources for randomness than non-rotational block devices. From a security perspective it is better to err on the side of caution than to allow entropy contributions from unreliable "random" sources. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-10-02md/raid5: disable 'DISCARD' by default due to safety concerns.NeilBrown
It has come to my attention (thanks Martin) that 'discard_zeroes_data' is only a hint. Some devices in some cases don't do what it says on the label. The use of DISCARD in RAID5 depends on reads from discarded regions being predictably zero. If a write to a previously discarded region performs a read-modify-write cycle it assumes that the parity block was consistent with the data blocks. If all were zero, this would be the case. If some are and some aren't this would not be the case. This could lead to data corruption after a device failure when data needs to be reconstructed from the parity. As we cannot trust 'discard_zeroes_data', ignore it by default and so disallow DISCARD on all raid4/5/6 arrays. As many devices are trustworthy, and as there are benefits to using DISCARD, add a module parameter to over-ride this caution and cause DISCARD to work if discard_zeroes_data is set. If a site want to enable DISCARD on some arrays but not on others they should select DISCARD support at the filesystem level, and set the raid456 module parameter. raid456.devices_handle_discard_safely=Y As this is a data-safety issue, I believe this patch is suitable for -stable. DISCARD support for RAID456 was added in 3.7 Cc: Shaohua Li <shli@kernel.org> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Heinz Mauelshagen <heinzm@redhat.com> Cc: stable@vger.kernel.org (3.7+) Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Fixes: 620125f2bf8ff0c4969b79653b54d7bcc9d40637 Signed-off-by: NeilBrown <neilb@suse.de>
2014-09-24Merge tag 'md/3.17-more-fixes' of git://git.neil.brown.name/mdLinus Torvalds
Pull bugfixes for md/raid1 from Neil Brown: "It is amazing how much easier it is to find bugs when you know one is there. Two bug reports resulted in finding 7 bugs! All are tagged for -stable. Those that can't cause (rare) data corruption, cause lockups. Particularly, but not only, fixing new "resync" code" * tag 'md/3.17-more-fixes' of git://git.neil.brown.name/md: md/raid1: fix_read_error should act on all non-faulty devices. md/raid1: count resync requests in nr_pending. md/raid1: update next_resync under resync_lock. md/raid1: Don't use next_resync to determine how far resync has progressed md/raid1: make sure resync waits for conflicting writes to complete. md/raid1: clean up request counts properly in close_sync() md/raid1: be more cautious where we read-balance during resync. md/raid1: intialise start_next_window for READ case to avoid hang
2014-09-22md/raid1: fix_read_error should act on all non-faulty devices.NeilBrown
If a devices is being recovered it is not InSync and is not Faulty. If a read error is experienced on that device, fix_read_error() will be called, but it ignores non-InSync devices. So it will neither fix the error nor fail the device. It is incorrect that fix_read_error() ignores non-InSync devices. It should only ignore Faulty devices. So fix it. This became a bug when we allowed reading from a device that was being recovered. It is suitable for any subsequent -stable kernel. Fixes: da8840a747c0dbf49506ec906757a6b87b9741e9 Cc: stable@vger.kernel.org (v3.5+) Reported-by: Alexander Lyakas <alex.bolshoy@gmail.com> Tested-by: Alexander Lyakas <alex.bolshoy@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-09-22md/raid1: count resync requests in nr_pending.NeilBrown
Both normal IO and resync IO can be retried with reschedule_retry() and so be counted into ->nr_queued, but only normal IO gets counted in ->nr_pending. Before the recent improvement to RAID1 resync there could only possibly have been one or the other on the queue. When handling a read failure it could only be normal IO. So when handle_read_error() called freeze_array() the fact that freeze_array only compares ->nr_queued against ->nr_pending was safe. But now that these two types can interleave, we can have both normal and resync IO requests queued, so we need to count them both in nr_pending. This error can lead to freeze_array() hanging if there is a read error, so it is suitable for -stable. Fixes: 79ef3a8aa1cb1523cc231c9a90a278333c21f761 cc: stable@vger.kernel.org (v3.13+) Reported-by: Brassow Jonathan <jbrassow@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-09-22md/raid1: update next_resync under resync_lock.NeilBrown
raise_barrier() uses next_resync as part of its calculations, so it really should be updated first, instead of afterwards. next_resync is always used under resync_lock so update it under resync lock to, just before it is used. That is safest. This could cause normal IO and resync IO to interact badly so it suitable for -stable. Fixes: 79ef3a8aa1cb1523cc231c9a90a278333c21f761 cc: stable@vger.kernel.org (v3.13+) Signed-off-by: NeilBrown <neilb@suse.de>