summaryrefslogtreecommitdiff
path: root/drivers/md
AgeCommit message (Collapse)Author
2014-01-24Merge tag 'md/3.14' of git://neil.brown.name/mdLinus Torvalds
Pull md updates from Neil Brown: "All bug fixes, two tagged for -stable" * tag 'md/3.14' of git://neil.brown.name/md: md/raid5: close recently introduced race in stripe_head management. md/raid5: fix long-standing problem with bitmap handling on write failure. md: check command validity early in md_ioctl(). md: ensure metadata is writen after raid level change. md/raid10: avoid fullsync when not necessary. md: allow a partially recovered device to be hot-added to an array. md: Change handling of save_raid_disk and metadata update during recovery.
2014-01-22Merge tag 'dm-3.14-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device-mapper changes from Mike Snitzer: "A lot of attention was paid to improving the thin-provisioning target's handling of metadata operation failures and running out of space. A new 'error_if_no_space' feature was added to allow users to error IOs rather than queue them when either the data or metadata space is exhausted. Additional fixes/features include: - a few fixes to properly support thin metadata device resizing - a solution for reliably waiting for a DM device's embedded kobject to be released before destroying the device - old dm-snapshot is updated to use the dm-bufio interface to take advantage of readahead capabilities that improve snapshot activation - new dm-cache target tunables to control how quickly data is promoted to the cache (fast) device - improved write efficiency of cluster mirror target by combining userspace flush and mark requests" * tag 'dm-3.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits) dm log userspace: allow mark requests to piggyback on flush requests dm space map metadata: fix bug in resizing of thin metadata dm cache: add policy name to status output dm thin: fix pool feature parsing dm sysfs: fix a module unload race dm snapshot: use dm-bufio prefetch dm snapshot: use dm-bufio dm snapshot: prepare for switch to using dm-bufio dm snapshot: use GFP_KERNEL when initializing exceptions dm cache: add block sizes and total cache blocks to status output dm btree: add dm_btree_find_lowest_key dm space map metadata: fix extending the space map dm space map common: make sure new space is used during extend dm: wait until embedded kobject is released before destroying a device dm: remove pointless kobject comparison in dm_get_from_kobject dm snapshot: call destroy_work_on_stack() to pair with INIT_WORK_ONSTACK() dm cache policy mq: introduce three promotion threshold tunables dm cache policy mq: use list_del_init instead of list_del + INIT_LIST_HEAD dm thin: fix set_pool_mode exposed pool operation races dm thin: eliminate the no_free_space flag ...
2014-01-21dm log userspace: allow mark requests to piggyback on flush requestsDongmao Zhang
In the cluster evironment, cluster write has poor performance because userspace_flush() has to contact a userspace program (cmirrord) for clear/mark/flush requests. But both mark and flush requests require cmirrord to communicate the message to all the cluster nodes for each flush call. This behaviour is really slow. To address this we now merge mark and flush requests together to reduce the kernel-userspace-kernel time. We allow a new directive, "integrated_flush" that can be used to instruct the kernel log code to combine flush and mark requests when directed by userspace. If not directed by userspace (due to an older version of the userspace code perhaps), the kernel will function as it did previously - preserving backwards compatibility. Additionally, flush requests are performed lazily when only clear requests exist. Signed-off-by: Dongmao Zhang <dmzhang@suse.com> Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-21Merge branch 'for-3.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "The bulk of changes are cleanups and preparations for the upcoming kernfs conversion. - cgroup_event mechanism which is and will be used only by memcg is moved to memcg. - pidlist handling is updated so that it can be served by seq_file. Also, the list is not sorted if sane_behavior. cgroup documentation explicitly states that the file is not sorted but it has been for quite some time. - All cgroup file handling now happens on top of seq_file. This is to prepare for kernfs conversion. In addition, all operations are restructured so that they map 1-1 to kernfs operations. - Other cleanups and low-pri fixes" * 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (40 commits) cgroup: trivial style updates cgroup: remove stray references to css_id doc: cgroups: Fix typo in doc/cgroups cgroup: fix fail path in cgroup_load_subsys() cgroup: fix missing unlock on error in cgroup_load_subsys() cgroup: remove for_each_root_subsys() cgroup: implement for_each_css() cgroup: factor out cgroup_subsys_state creation into create_css() cgroup: combine css handling loops in cgroup_create() cgroup: reorder operations in cgroup_create() cgroup: make for_each_subsys() useable under cgroup_root_mutex cgroup: css iterations and css_from_dir() are safe under cgroup_mutex cgroup: unify pidlist and other file handling cgroup: replace cftype->read_seq_string() with cftype->seq_show() cgroup: attach cgroup_open_file to all cgroup files cgroup: generalize cgroup_pidlist_open_file cgroup: unify read path so that seq_file is always used cgroup: unify cgroup_write_X64() and cgroup_write_string() cgroup: remove cftype->read(), ->read_map() and ->write() hugetlb_cgroup: convert away from cftype->read() ...
2014-01-22md/raid5: close recently introduced race in stripe_head management.NeilBrown
As release_stripe and __release_stripe decrement ->count and then manipulate ->lru both under ->device_lock, it is important that get_active_stripe() increments ->count and clears ->lru also under ->device_lock. However we currently list_del_init ->lru under the lock, but increment the ->count outside the lock. This can lead to races and list corruption. So move the atomic_inc(&sh->count) up inside the ->device_lock protected region. Note that we still increment ->count without device lock in the case where get_free_stripe() was called, and in fact don't take ->device_lock at all in that path. This is safe because if the stripe_head can be found by get_free_stripe, then the hash lock assures us the no-one else could possibly be calling release_stripe() at the same time. Fixes: 566c09c53455d7c4f1130928ef8071da1a24ea65 Cc: stable@vger.kernel.org (3.13) Reported-and-tested-by: Ian Kumlien <ian.kumlien@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-21dm space map metadata: fix bug in resizing of thin metadataJoe Thornber
This bug was introduced in commit 7e664b3dec431e ("dm space map metadata: fix extending the space map"). When extending a dm-thin metadata volume we: - Switch the space map into a simple bootstrap mode, which allocates all space linearly from the newly added space. - Add new bitmap entries for the new space - Increment the reference counts for those newly allocated bitmap entries - Commit changes to disk - Switch back out of bootstrap mode. But, the disk commit may allocate space itself, if so this fact will be lost when switching out of bootstrap mode. The bug exhibited itself as an error when the bitmap_root, with an erroneous ref count of 0, was subsequently decremented as part of a later disk commit. This would cause the disk commit to fail, and thinp to enter read_only mode. The metadata was not damaged (thin_check passed). The fix is to put the increments + commit into a loop, running until the commit has not allocated extra space. In practise this loop only runs twice. With this fix the following device mapper testsuite test passes: dmtest run --suite thin-provisioning -n thin_remove_works_after_resize Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # depends on commit 7e664b3dec431e
2014-01-20Merge tag 'driver-core-3.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core / sysfs patches from Greg KH: "Here's the big driver core and sysfs patch set for 3.14-rc1. There's a lot of work here moving sysfs logic out into a "kernfs" to allow other subsystems to also have a virtual filesystem with the same attributes of sysfs (handle device disconnect, dynamic creation / removal as needed / unneeded, etc) This is primarily being done for the cgroups filesystem, but the goal is to also move debugfs to it when it is ready, solving all of the known issues in that filesystem as well. The code isn't completed yet, but all should be stable now (there is a big section that was reverted due to problems found when testing) There's also some other smaller fixes, and a driver core addition that allows for a "collection" of objects, that the DRM people will be using soon (it's in this tree to make merges after -rc1 easier) All of this has been in linux-next with no reported issues" * tag 'driver-core-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (113 commits) kernfs: associate a new kernfs_node with its parent on creation kernfs: add struct dentry declaration in kernfs.h kernfs: fix get_active failure handling in kernfs_seq_*() Revert "kernfs: fix get_active failure handling in kernfs_seq_*()" Revert "kernfs: replace kernfs_node->u.completion with kernfs_root->deactivate_waitq" Revert "kernfs: remove KERNFS_ACTIVE_REF and add kernfs_lockdep()" Revert "kernfs: remove KERNFS_REMOVED" Revert "kernfs: restructure removal path to fix possible premature return" Revert "kernfs: invoke kernfs_unmap_bin_file() directly from __kernfs_remove()" Revert "kernfs: remove kernfs_addrm_cxt" Revert "kernfs: make kernfs_get_active() block if the node is deactivated but not removed" Revert "kernfs: implement kernfs_{de|re}activate[_self]()" Revert "kernfs, sysfs, driver-core: implement kernfs_remove_self() and its wrappers" Revert "pci: use device_remove_file_self() instead of device_schedule_callback()" Revert "scsi: use device_remove_file_self() instead of device_schedule_callback()" Revert "s390: use device_remove_file_self() instead of device_schedule_callback()" Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()" Revert "kernfs: remove unnecessary NULL check in __kernfs_remove()" kernfs: remove unnecessary NULL check in __kernfs_remove() drivers/base: provide an infrastructure for componentised subsystems ...
2014-01-16dm cache: add policy name to status outputMike Snitzer
The cache's policy may have been established using the "default" alias, which is currently the "mq" policy but the default policy may change in the future. It is useful to know exactly which policy is being used. Add a 'real' member to the dm_cache_policy_type structure and have the "default" dm_cache_policy_type point to the real "mq" dm_cache_policy_type. Update dm_cache_policy_get_name() to check if real is set, if so report the name of the real policy (not the alias). Requested-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-15dm thin: fix pool feature parsingMike Snitzer
Commit 787a996cb251e20 ("dm thin: add error_if_no_space feature") mistakenly forgot to increase the number of feature args supported. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-16md/raid5: fix long-standing problem with bitmap handling on write failure.NeilBrown
Before a write starts we set a bit in the write-intent bitmap. When the write completes we clear that bit if the write was successful to all devices. However if the write wasn't fully successful we should not clear the bit. If the faulty drive is subsequently re-added, the fact that the bit is still set ensure that we will re-write the data that is missing. This logic is mediated by the STRIPE_DEGRADED flag - we only clear the bitmap bit when this flag is not set. Currently we correctly set the flag if a write starts when some devices are failed or missing. But we do *not* set the flag if some device failed during the write attempt. This is wrong and can result in clearing the bit inappropriately. So: set the flag when a write fails. This bug has been present since bitmaps were introduces, so the fix is suitable for any -stable kernel. Reported-by: Ethan Wilson <ethan.wilson@shiftmail.org> Cc: stable@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-16md: check command validity early in md_ioctl().Nicolas Schichan
Verify that the cmd parameter passed to md_ioctl() is valid before doing anything. This fixes mddev->hold_active being set to 0 when an invalid ioctl command is passed to md_ioctl() before the array has been configured. Clearing mddev->hold_active in that case can lead to a livelock situation when an invalid ioctl number is given to md_ioctl() by a process when the mddev is currently being opened by another process: Process 1 Process 2 --------- --------- md_alloc() mddev_find() -> returns a new mddev with hold_active == UNTIL_IOCTL add_disk() -> sends KOBJ_ADD uevent (sees KOBJ_ADD uevent for device) md_open() md_ioctl(INVALID_IOCTL) -> returns ENODEV and clears mddev->hold_active md_release() md_put() -> deletes the mddev as hold_active is 0 md_open() mddev_find() -> returns a newly allocated mddev with mddev->gendisk == NULL -> returns with ERESTARTSYS (kernel restarts the open syscall) Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-15Merge tag 'md/3.13-fixes' of git://neil.brown.name/mdLinus Torvalds
Pull late md fixes from Neil Brown: "Half a dozen md bug fixes. All of these fix real bugs the people have hit, and are tagged for -stable. Sorry they are late .... Christmas holidays and all that. Hopefully they can still squeak into 3.13" * tag 'md/3.13-fixes' of git://neil.brown.name/md: md: fix problem when adding device to read-only array with bitmap. md/raid10: fix bug when raid10 recovery fails to recover a block. md/raid5: fix a recently broken BUG_ON(). md/raid1: fix request counting bug in new 'barrier' code. md/raid10: fix two bugs in handling of known-bad-blocks. md/raid5: Fix possible confusion when multiple write errors occur.
2014-01-14dm sysfs: fix a module unload raceMikulas Patocka
This reverts commit be35f48610 ("dm: wait until embedded kobject is released before destroying a device") and provides an improved fix. The kobject release code that calls the completion must be placed in a non-module file, otherwise there is a module unload race (if the process calling dm_kobject_release is preempted and the DM module unloaded after the completion is triggered, but before dm_kobject_release returns). To fix this race, this patch moves the completion code to dm-builtin.c which is always compiled directly into the kernel if BLK_DEV_DM is selected. The patch introduces a new dm_kobject_holder structure, its purpose is to keep the completion and kobject in one place, so that it can be accessed from non-module code without the need to export the layout of struct mapped_device to that code. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-01-14dm snapshot: use dm-bufio prefetchMikulas Patocka
This patch modifies dm-snapshot so that it prefetches the buffers when loading the exceptions. The number of buffers read ahead is specified in the DM_PREFETCH_CHUNKS macro. The current value for DM_PREFETCH_CHUNKS (12) was found to provide the best performance on a single 15k SCSI spindle. In the future we may modify this default or make it configurable. Also, introduce the function dm_bufio_set_minimum_buffers to setup bufio's number of internal buffers before freeing happens. dm-bufio may hold more buffers if enough memory is available. There is no guarantee that the specified number of buffers will be available - if you need a guarantee, use the argument reserved_buffers for dm_bufio_client_create. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-14dm snapshot: use dm-bufioMikulas Patocka
Use dm-bufio for initial loading of the exceptions. Introduce a new function dm_bufio_forget that frees the given buffer. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-14dm snapshot: prepare for switch to using dm-bufioMikulas Patocka
Change the functions get_exception, read_exception and insert_exceptions so that ps->area is passed as an argument. This patch doesn't change any functionality, but it refactors the code to allow for a cleaner switch over to using dm-bufio. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-14dm snapshot: use GFP_KERNEL when initializing exceptionsMikulas Patocka
The list of initial exceptions is loaded in the target constructor. We are allowed to allocate memory with GFP_KERNEL at this point. So, change alloc_completed_exception to use GFP_KERNEL when being called from the constructor. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-14md: ensure metadata is writen after raid level change.NeilBrown
level_store() currently does not make sure the metadata is updates to reflect the new raid level. It simply sets MD_CHANGE_DEVS. Any level with a ->thread will quickly notice this and update the metadata. However RAID0 and Linear do not have a thread so no metadata update happens until the array is stopped. At that point the metadata is written. This is later that we would like. While the delay doesn't risk any data it can cause confusion. So if there is no md thread, immediately update the metadata after a level change. Reported-by: Richard Michael <rmichael@edgeofthenet.org> Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md/raid10: avoid fullsync when not necessary.NeilBrown
This is the raid10 equivalent of commit 4f0a5e012cf41321d611e7cad63e1017d143d138 MD RAID1: Further conditionalize 'fullsync' If a device in a newly assembled array is not fully recovered we currently do a fully resync by don't need to. Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md: allow a partially recovered device to be hot-added to an array.NeilBrown
When adding a new device into an array it is normally important to clear any stale data from ->recovery_offset else the new device may not be recovered properly. However when re-adding a device which is known to be nearly in-sync, this is not needed and can be detrimental. The (bitmap-based) resync will still happen, and further recovery is only needed from where-ever it was already up to. So if save_raid_disk is set, signifying a re-add, don't clear ->recovery_offset. Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md: Change handling of save_raid_disk and metadata update during recovery.NeilBrown
Since commit d70ed2e4fafdbef0800e739 MD: Allow restarting an interrupted incremental recovery. we don't write out the metadata to devices while they are recovering. This had a good reason, but has unfortunate consequences. This patch changes things to make them work better. At issue is what happens if the array is shut down while a recovery is happening, particularly a bitmap-guided recovery. Ideally the recovery should pick up where it left off. However the metadata cannot represent the state "A recovery is in process which is guided by the bitmap". Before the above mentioned commit, we wrote metadata to the device which said "this is being recovered and it is up to <here>". So after a restart, a full recovery (not bitmap-guided) would happen from where-ever it was up to. After the commit the metadata wasn't updated so it still said "This device is fully in sync with <this> event count". That leads to a bitmap-based recovery following the whole bitmap, which should be a lot less work than a full recovery from some starting point. So this was an improvement. However updates some metadata but not all leads to other problems. In particular, the metadata written to the fully-up-to-date device record that the array has all devices present (even though some are recovering). So on restart, mdadm wants to find all devices and expects them to have current event counts. Obviously it doesn't (some have old event counts) so (when assembling with --incremental) it waits indefinitely for the rest of the expected devices. It really is wrong to not update all the metadata together. Do that is bound to cause confusion. Instead, we should make it possible to record the truth in the metadata. i.e. we need to be able to record that a device is being recovered based on the bitmap. We already have a Feature flag to say that recovery is happening. We now add another one to say that it is a bitmap-based recovery. With this we can remove the code that disables the write-out of metadata on some devices. So this patch: - moves the setting of 'saved_raid_disk' from add_new_disk to the validate_super methods. This makes sure it is always set properly, both when adding a new device to an array, and when assembling an array from a collection of devices. - Adds a metadata flag MD_FEATURE_RECOVERY_BITMAP which is only used if MD_FEATURE_RECOVERY_OFFSET is set, and record that a bitmap-based recovery is allowed. This is only present in v1.x metadata. v0.90 doesn't support devices which are in the middle of recovery at all. - Only skips writing metadata to Faulty devices. - Also allows rdev state to be set to "-insync" via sysfs. This can be used for external-metadata arrays. When the 'role' is set the device is assumed to be in-sync. If, after setting the role, we set the state to "-insync", the role is moved to saved_raid_disk which effectively says the device is partly in-sync with that slot and needs a bitmap recovery. Cc: Andrei Warkentin <andreiw@vmware.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md: fix problem when adding device to read-only array with bitmap.NeilBrown
If an array is started degraded, and then the missing device is found it can be re-added and a minimal bitmap-based recovery will bring it fully up-to-date. If the array is read-only a recovery would not be allowed. But also if the array is read-only and the missing device was present very recently, then there could be no need for any recovery at all, so we simply include the device in the read-only array without any recovery. However... if the missing device was removed a little longer ago it could be missing some updates, but if a bitmap is present it will be conditionally accepted pending a bitmap-based update. We don't currently detect this case properly and will include that old device into the read-only array with no recovery even though it really needs a recovery. This patch keeps track of whether a bitmap-based-recovery is really needed or not in the new Bitmap_sync rdev flag. If that is set, then the device will not be added to a read-only array. Cc: Andrei Warkentin <andreiw@vmware.com> Fixes: d70ed2e4fafdbef0800e73942482bb075c21578b Cc: stable@vger.kernel.org (3.2+) Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md/raid10: fix bug when raid10 recovery fails to recover a block.NeilBrown
commit e875ecea266a543e643b19e44cf472f1412708f9 md/raid10 record bad blocks as needed during recovery. added code to the "cannot recover this block" path to record a bad block rather than fail the whole recovery. Unfortunately this new case was placed *after* r10bio was freed rather than *before*, yet it still uses r10bio. This is will crash with a null dereference. So move the freeing of r10bio down where it is safe. Cc: stable@vger.kernel.org (v3.1+) Fixes: e875ecea266a543e643b19e44cf472f1412708f9 Reported-by: Damian Nowak <spam@nowaker.net> URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181 Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md/raid5: fix a recently broken BUG_ON().NeilBrown
commit 6d183de4077191d1201283a9035ce57a9b05254d md/raid5: fix newly-broken locking in get_active_stripe. simplified a BUG_ON, but removed too much so now it sometimes fires when it shouldn't. When the STRIPE_EXPANDING flag is set, the stripe_head might be on a special list while multiple stripe_heads are collected, or it might not be on any list, even a 'free' list when the refcount is zero. As long as STRIPE_EXPANDING is set, it will be found and added back to a list eventually. So both of the BUG_ONs which test for the ->lru being empty or not need to avoid the case where STRIPE_EXPANDING is set. The patch which broke this was marked for -stable, so this patch needs to be applied to any branch that received 6d183de4 Fixes: 6d183de4077191d1201283a9035ce57a9b05254d Cc: stable@vger.kernel.org (any release to which above was applied) Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md/raid1: fix request counting bug in new 'barrier' code.NeilBrown
The new iobarrier implementation in raid1 (which keeps normal writes and resync activity separate) counts every request what is not before the current resync point in either next_window_requests or current_window_requests. It flags that the request is counted by setting ->start_next_window. allow_barrier follows this model exactly and decrements one of the *_window_requests if and only if ->start_next_window is set. However wait_barrier(), which increments *_window_requests uses a slightly different test for setting -.start_next_window (which is set from the return value of this function). So there is a possibility of the counts getting out of sync, and this leads to the resync hanging. So change wait_barrier() to return a non-zero value in exactly the same cases that it increments *_window_requests. But was introduced in 3.13-rc1. Reported-by: Bruno Wolff III <bruno@wolff.to> URL: https://bugzilla.kernel.org/show_bug.cgi?id=68061 Fixes: 79ef3a8aa1cb1523cc231c9a90a278333c21f761 Cc: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md/raid10: fix two bugs in handling of known-bad-blocks.NeilBrown
If we discover a bad block when reading we split the request and potentially read some of it from a different device. The code path of this has two bugs in RAID10. 1/ we get a spin_lock with _irq, but unlock without _irq!! 2/ The calculation of 'sectors_handled' is wrong, as can be clearly seen by comparison with raid1.c This leads to at least 2 warnings and a probable crash is a RAID10 ever had known bad blocks. Cc: stable@vger.kernel.org (v3.1+) Fixes: 856e08e23762dfb92ffc68fd0a8d228f9e152160 Reported-by: Damian Nowak <spam@nowaker.net> URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181 Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-14md/raid5: Fix possible confusion when multiple write errors occur.NeilBrown
commit 5d8c71f9e5fbdd95650be00294d238e27a363b5c md: raid5 crash during degradation Fixed a crash in an overly simplistic way which could leave R5_WriteError or R5_MadeGood set in the stripe cache for devices for which it is no longer relevant. When those devices are removed and spares added the flags are still set and can cause incorrect behaviour. commit 14a75d3e07c784c004b4b44b34af996b8e4ac453 md/raid5: preferentially read from replacement device if possible. Fixed the same bug if a more effective way, so we can now revert the original commit. Reported-and-tested-by: Alexander Lyakas <alex.bolshoy@gmail.com> Cc: stable@vger.kernel.org (3.2+ - 3.2 will need a different fix though) Fixes: 5d8c71f9e5fbdd95650be00294d238e27a363b5c Signed-off-by: NeilBrown <neilb@suse.de>
2014-01-13cgroup: remove stray references to css_idHugh Dickins
Trivial: remove the few stray references to css_id, which itself was removed in v3.13's 2ff2a7d03bbe "cgroup: kill css_id". Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-01-10dm cache: add block sizes and total cache blocks to status outputMike Snitzer
Improve cache_status to emit: <metadata block size> <#used metadata blocks>/<#total metadata blocks> <cache block size> <#used cache blocks>/<#total cache blocks> ... Adding the block sizes allows for easier calculation of the overall size of both the metadata and cache devices. Adding <#total cache blocks> provides useful context for how much of the cache is used. Unfortunately these additions to the status will require updates to users' scripts that monitor the cache status. But these changes help provide more comprehensive information about the cache device and will simplify tools that are being developed to manage dm-cache devices -- because they won't need to issue 3 operations to cobble together the information that we can easily provide via a single status ioctl. While updating the status documentation in cache.txt spaces were tabify'd. Requested-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-09dm btree: add dm_btree_find_lowest_keyJoe Thornber
dm_btree_find_lowest_key is the reciprocal of dm_btree_find_highest_key. Factor out common code for dm_btree_find_{highest,lowest}_key. dm_btree_find_lowest_key is needed for an upcoming DM target, as such it is best to get this interface in place. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm space map metadata: fix extending the space mapJoe Thornber
When extending a metadata space map we should do the first commit whilst still in bootstrap mode -- a mode where all blocks get allocated in the new area. That way the commit overhead is allocated from the newly added space. Otherwise we risk running out of space. With this fix, and the previous commit "dm space map common: make sure new space is used during extend", the following device mapper testsuite test passes: dmtest run --suite thin-provisioning -n /resize_metadata_no_io/ Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-01-07dm space map common: make sure new space is used during extendJoe Thornber
When extending a low level space map we should update nr_blocks at the start so the new space is used for the index entries. Otherwise extend can fail, e.g.: sm_metadata_extend call sequence that fails: -> sm_ll_extend -> dm_tm_new_block -> dm_sm_new_block -> sm_bootstrap_new_block => returns -ENOSPC because smm->begin == smm->ll.nr_blocks Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-01-07dm: wait until embedded kobject is released before destroying a deviceMikulas Patocka
There may be other parts of the kernel holding a reference on the dm kobject. We must wait until all references are dropped before deallocating the mapped_device structure. The dm_kobject_release method signals that all references are dropped via completion. But dm_kobject_release doesn't free the kobject (which is embedded in the mapped_device structure). This is the sequence of operations: * when destroying a DM device, call kobject_put from dm_sysfs_exit * wait until all users stop using the kobject, when it happens the release method is called * the release method signals the completion and should return without delay * the dm device removal code that waits on the completion continues * the dm device removal code drops the dm_mod reference the device had * the dm device removal code frees the mapped_device structure that contains the kobject Using kobject this way should avoid the module unload race that was mentioned at the beginning of this thread: https://lkml.org/lkml/2014/1/4/83 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-01-07dm: remove pointless kobject comparison in dm_get_from_kobjectMikulas Patocka
The comparison is always true and the compiler optimizes it out anyway. Milan offered additional context relative to the original commit 784aae735d ("dm: add name and uuid to sysfs") which introduced the code: "I think it is just relict of some experiments before I committed this simple embedded sysfs kobj handling". Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm snapshot: call destroy_work_on_stack() to pair with INIT_WORK_ONSTACK()Chuansheng Liu
In case CONFIG_DEBUG_OBJECTS_WORK is defined, it is needed to call destroy_work_on_stack() which frees the debug object to pair with INIT_WORK_ONSTACK(). Signed-off-by: Liu, Chuansheng <chuansheng.liu@intel.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm cache policy mq: introduce three promotion threshold tunablesJoe Thornber
Internally the mq policy maintains a promotion threshold variable. If the hit count of a block not in the cache goes above this threshold it gets promoted to the cache. This patch introduces three new tunables that allow you to tweak the promotion threshold by adding a small value. These adjustments depend on the io type: read_promote_adjustment: READ io, default 4 write_promote_adjustment: WRITE io, default 8 discard_promote_adjustment: READ/WRITE io to a discarded block, default 1 If you're trying to quickly warm a new cache device you may wish to reduce these to encourage promotion. Remember to switch them back to their defaults after the cache fills though. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm cache policy mq: use list_del_init instead of list_del + INIT_LIST_HEADWei Yongjun
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Acked-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm thin: fix set_pool_mode exposed pool operation racesMike Snitzer
The pool mode must not be switched until after the corresponding pool process_* methods have been established. Otherwise, because set_pool_mode() isn't interlocked with the IO path for performance reasons, the IO path can end up executing process_* operations that don't match the mode. This patch eliminates problems like the following (as seen on really fast PCIe SSD storage when transitioning the pool's mode from PM_READ_ONLY to PM_WRITE): kernel: device-mapper: thin: 253:2: reached low water mark for data device: sending event. kernel: device-mapper: thin: 253:2: no free data space available. kernel: device-mapper: thin: 253:2: switching pool to read-only mode kernel: device-mapper: thin: 253:2: switching pool to write mode kernel: ------------[ cut here ]------------ kernel: WARNING: CPU: 11 PID: 7564 at drivers/md/dm-thin.c:995 handle_unserviceable_bio+0x146/0x160 [dm_thin_pool]() ... kernel: Workqueue: dm-thin do_worker [dm_thin_pool] kernel: 00000000000003e3 ffff880308831cc8 ffffffff8152ebcb 00000000000003e3 kernel: 0000000000000000 ffff880308831d08 ffffffff8104c46c ffff88032502a800 kernel: ffff880036409000 ffff88030ec7ce00 0000000000000001 00000000ffffffc3 kernel: Call Trace: kernel: [<ffffffff8152ebcb>] dump_stack+0x49/0x5e kernel: [<ffffffff8104c46c>] warn_slowpath_common+0x8c/0xc0 kernel: [<ffffffff8104c4ba>] warn_slowpath_null+0x1a/0x20 kernel: [<ffffffffa001e2c6>] handle_unserviceable_bio+0x146/0x160 [dm_thin_pool] kernel: [<ffffffffa001f276>] process_bio_read_only+0x136/0x180 [dm_thin_pool] kernel: [<ffffffffa0020b75>] process_deferred_bios+0xc5/0x230 [dm_thin_pool] kernel: [<ffffffffa0020d31>] do_worker+0x51/0x60 [dm_thin_pool] kernel: [<ffffffff81067823>] process_one_work+0x183/0x490 kernel: [<ffffffff81068c70>] worker_thread+0x120/0x3a0 kernel: [<ffffffff81068b50>] ? manage_workers+0x160/0x160 kernel: [<ffffffff8106e86e>] kthread+0xce/0xf0 kernel: [<ffffffff8106e7a0>] ? kthread_freezable_should_stop+0x70/0x70 kernel: [<ffffffff8153b3ec>] ret_from_fork+0x7c/0xb0 kernel: [<ffffffff8106e7a0>] ? kthread_freezable_should_stop+0x70/0x70 kernel: ---[ end trace 3f00528e08ffa55c ]--- kernel: device-mapper: thin: pool mode is PM_WRITE not PM_READ_ONLY like expected!? dm-thin.c:995 was the WARN_ON_ONCE(get_pool_mode(pool) != PM_READ_ONLY); at the top of handle_unserviceable_bio(). And as the additional debugging I had conveys: the pool mode was _not_ PM_READ_ONLY like expected, it was already PM_WRITE, yet pool->process_bio was still set to process_bio_read_only(). Also, while fixing this up, reduce logging of redundant pool mode transitions by checking new_mode is different from old_mode. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-01-07dm thin: eliminate the no_free_space flagMike Snitzer
The pool's error_if_no_space flag can easily serve the same purpose that no_free_space did, namely: control whether handle_unserviceable_bio() will error a bio or requeue it. This is cleaner since error_if_no_space is established when the pool's features are processed during table load. So it avoids managing the no_free_space flag by taking the pool's spinlock. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm thin: add error_if_no_space featureMike Snitzer
If the pool runs out of data or metadata space, the pool can either queue or error the IO destined to the data device. The default is to queue the IO until more space is added. An admin may now configure the pool to error IO when no space is available by setting the 'error_if_no_space' feature when loading the thin-pool table. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07dm thin: requeue bios to DM core if no_free_space and in read-only modeMike Snitzer
Now that we switch the pool to read-only mode when the data device runs out of space it causes active writers to get IO errors once we resume after resizing the data device. If no_free_space is set, save bios to the 'retry_on_resume_list' and requeue them on resume (once the data or metadata device may have been resized). With this patch the resize_io test passes again (on slower storage): dmtest run --suite thin-provisioning -n /resize_io/ Later patches fix some subtle races associated with the pool mode transitions done as part of the pool's -ENOSPC handling. These races are exposed on fast storage (e.g. PCIe SSD). Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07dm thin: cleanup and improve no space handlingMike Snitzer
Factor out_of_data_space() out of alloc_data_block(). Eliminate the use of 'no_free_space' as a latch in alloc_data_block() -- this is no longer needed now that we switch to read-only mode when we run out of data or metadata space. In a later patch, the 'no_free_space' flag will be eliminated entirely (in favor of checking metadata rather than relying on a transient flag). Move no metdata space handling into metdata_operation_failed(). Set no_free_space when metadata space is exhausted too. This is useful, because it offers consistency, for the following patch that will requeue data IOs if no_free_space. Also, rename no_space() to retry_bios_on_resume(). Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07dm thin: log info when growing the data or metadata deviceMike Snitzer
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07dm thin: handle metadata failures more consistentlyJoe Thornber
Introduce metadata_operation_failed() wrappers, around set_pool_mode(), to assist with improving the consistency of how metadata failures are handled. Logging is improved and metadata operation failures trigger read-only mode immediately. Also, eliminate redundant set_pool_mode() calls in the two alloc_data_block() caller's error paths. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm thin: factor out check_low_water_mark and use boolsJoe Thornber
Factor check_low_water_mark() out of alloc_data_block(). Change a couple unsigned flags in the pool structure to bool. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm thin: add mappings to end of prepared_* listsMike Snitzer
Mappings could be processed in descending logical block order, particularly if buffered IO is used. This could adversely affect the latency of IO processing. Fix this by adding mappings to the end of the 'prepared_mappings' and 'prepared_discards' lists. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07dm thin: return error from alloc_data_block if pool is not in write modeJoe Thornber
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-01-07dm thin: use bool rather than unsigned for flags in structuresMike Snitzer
Also, move 'err' member in dm_thin_new_mapping structure to eliminate 4 byte hole (reduces size from 88 bytes to 80). Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07dm persistent data: cleanup dm-thin specific references in textMike Snitzer
DM's persistent-data library is now used my multiple targets so exclusive references to "pool" or "thin provisioning" need to be cleaned up. Adjust Kconfig's DM_DEBUG_BLOCK_STACK_TRACING text and remove "pool" from a block manager error message. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2014-01-07dm space map metadata: limit errors in sm_metadata_new_blockMike Snitzer
The "unable to allocate new metadata block" error can be a particularly verbose error if there is a systemic issue with the metadata device. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>