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* Merge tag 'for-5.2/dm-changes-v2' of ↵Linus Torvalds2019-05-161-1/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Improve DM snapshot target's scalability by using finer grained locking. Requires some list_bl interface improvements. - Add ability for DM integrity to use a bitmap mode, that tracks regions where data and metadata are out of sync, instead of using a journal. - Improve DM thin provisioning target to not write metadata changes to disk if the thin-pool and associated thin devices are merely activated but not used. This avoids metadata corruption due to concurrent activation of thin devices across different OS instances (e.g. split brain scenarios, which ultimately would be avoided if proper device filters were used -- but not having proper filtering has proven a very common configuration mistake) - Fix missing call to path selector type->end_io in DM multipath. This fixes reported performance problems due to inaccurate path selector IO accounting causing an imbalance of IO (e.g. avoiding issuing IO to particular path due to it seemingly being heavily used). - Fix bug in DM cache metadata's loading of its discard bitset that could lead to all cache blocks being discarded if the very first cache block was discarded (thankfully in practice the first cache block is generally in use; be it FS superblock, partition table, disk label, etc). - Add testing-only DM dust target which simulates a device that has failing sectors and/or read failures. - Fix a DM init error path reference count hang that caused boot hangs if user supplied malformed input on kernel commandline. - Fix a couple issues with DM crypt target's logging being overly verbose or lacking context. - Various other small fixes to DM init, DM multipath, DM zoned, and DM crypt. * tag 'for-5.2/dm-changes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (42 commits) dm: fix a couple brace coding style issues dm crypt: print device name in integrity error message dm crypt: move detailed message into debug level dm ioctl: fix hang in early create error condition dm integrity: whitespace, coding style and dead code cleanup dm integrity: implement synchronous mode for reboot handling dm integrity: handle machine reboot in bitmap mode dm integrity: add a bitmap mode dm integrity: introduce a function add_new_range_and_wait() dm integrity: allow large ranges to be described dm ingerity: pass size to dm_integrity_alloc_page_list() dm integrity: introduce rw_journal_sectors() dm integrity: update documentation dm integrity: don't report unused options dm integrity: don't check null pointer before kvfree and vfree dm integrity: correctly calculate the size of metadata area dm dust: Make dm_dust_init and dm_dust_exit static dm dust: remove redundant unsigned comparison to less than zero dm mpath: always free attached_handler_name in parse_path() dm init: fix max devices/targets checks ...
| * dm snapshot: Make exception tables scalableNikos Tsironis2019-04-181-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use list_bl to implement the exception hash tables' buckets. This change permits concurrent access, to distinct buckets, by multiple threads. Also, implement helper functions to lock and unlock the exception tables based on the chunk number of the exception at hand. We retain the global locking, by means of down_write(), which is replaced by the next commit. Still, we must acquire the per-bucket spinlocks when accessing the hash tables, since list_bl does not allow modification on unlocked lists. Co-developed-by: Ilias Tsitsimpis <iliastsi@arrikto.com> Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com> Acked-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* | block: remove CONFIG_LBDAFChristoph Hellwig2019-04-061-26/+2
|/ | | | | | | | | | | | | | | | Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit architectures. These types are required to support block device and/or file sizes larger than 2 TiB, and have generally defaulted to on for a long time. Enabling the option only increases the i386 tinyconfig size by 145 bytes, and many data structures already always use 64-bit values for their in-core and on-disk data structures anyway, so there should not be a large change in dynamic memory usage either. Dropping this option removes a somewhat weird non-default config that has cause various bugs or compiler warnings when actually used. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* dm snapshot: fix hung bios when copy error occursMikulas Patocka2016-01-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When there is an error copying a chunk dm-snapshot can incorrectly hold associated bios indefinitely, resulting in hung IO. The function copy_callback sets pe->error if there was error copying the chunk, and then calls complete_exception. complete_exception calls pending_complete on error, otherwise it calls commit_exception with commit_callback (and commit_callback calls complete_exception). The persistent exception store (dm-snap-persistent.c) assumes that calls to prepare_exception and commit_exception are paired. persistent_prepare_exception increases ps->pending_count and persistent_commit_exception decreases it. If there is a copy error, persistent_prepare_exception is called but persistent_commit_exception is not. This results in the variable ps->pending_count never returning to zero and that causes some pending exceptions (and their associated bios) to be held forever. Fix this by unconditionally calling commit_exception regardless of whether the copy was successful. A new "valid" parameter is added to commit_exception -- when the copy fails this parameter is set to zero so that the chunk that failed to copy (and all following chunks) is not recorded in the snapshot store. Also, remove commit_callback now that it is merely a wrapper around pending_complete. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
* dm snapshot: add new persistent store option to support overflowMike Snitzer2015-10-091-2/+3
| | | | | | | | | | | | | | | Commit 76c44f6d80 introduced the possibly for "Overflow" to be reported by the snapshot device's status. Older userspace (e.g. lvm2) does not handle the "Overflow" status response. Fix this incompatibility by requiring newer userspace code, that can cope with "Overflow", request the persistent store with overflow support by using "PO" (Persistent with Overflow) for the snapshot store type. Reported-by: Zdenek Kabelac <zkabelac@redhat.com> Fixes: 76c44f6d80 ("dm snapshot: don't invalidate on-disk image on snapshot write overflow") Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm snapshot: test chunk size against both origin and snapshotMikulas Patocka2010-08-121-1/+2
| | | | | | | | | | | | | | | | Validate chunk size against both origin and snapshot sector size Don't allow chunk size smaller than either origin or snapshot logical sector size. Reading or writing data not aligned to sector size is not allowed and causes immediate errors. This requires us to open the origin before initialising the exception store and to export dm_snap_origin. Cc: stable@kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: add mergingMikulas Patocka2009-12-101-0/+11
| | | | | | | | | | | | | | | Merging is started when origin is resumed and it is stopped when origin is suspended or when the merging snapshot is destroyed or errors are detected. Merging is not yet interlocked with writes: this will be handled in subsequent patches. The code relies on callbacks from a private kcopyd thread. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm exception store: add merge specific methodsMikulas Patocka2009-12-101-0/+17
| | | | | | | | | | | | | | | | | | | | Add functions that decide how many consecutive chunks of snapshot to merge back into the origin next and to update the metadata afterwards. prepare_merge provides a pointer to the most recent still-to-be-merged chunk and returns how many previous ones are consecutive and can be processed together. commit_merge removes the nr_merged most-recent chunks permanently from the exception store. The number must not exceed that returned by prepare_merge. Introduce NUM_SNAPSHOT_HDR_CHUNKS to show where the snapshot header chunk is accounted for. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: move cow ref from exception store to snap coreMike Snitzer2009-12-101-3/+9
| | | | | | | | | | | | | | Store the reference to the snapshot cow device in the core snapshot code instead of each exception store. It can be accessed through the new function dm_snap_cow(). Exception stores should each now maintain a reference to their parent snapshot struct. This is cleaner and makes part of the forthcoming snapshot merge code simpler. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Reviewed-by: Jonathan Brassow <jbrassow@redhat.com> Cc: Mikulas Patocka <mpatocka@redhat.com>
* dm snapshot: add allocated metadata to snapshot statusMike Snitzer2009-12-101-3/+3
| | | | | | | | | | | | Add number of sectors used by metadata to the end of the snapshot's status line. Renamed dm_exception_store_type's 'fraction_full' to 'usage'. Renamed arguments to be clearer about what is being returned. Also added 'metadata_sectors'. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: rename dm_snap_exception to dm_exceptionJon Brassow2009-12-101-7/+7
| | | | | | | | | | | The exception structure is not necessarily just a snapshot element (especially after we pull it out of dm-snap.c). Renaming appropriately. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: simplify sector_to_chunk expressionMikulas Patocka2009-12-101-1/+1
| | | | | | | | | | | | Removed unnecessary 'and' masking: The right shift discards the lower bits so there is no need to clear them. (A later patch needs this change to support a 32-bit chunk_mask.) Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Reviewed-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: use unsigned integer chunk sizeMikulas Patocka2009-10-161-4/+4
| | | | | | | | | | | | | | Use unsigned integer chunk size. Maximum chunk size is 512kB, there won't ever be need to use 4GB chunk size, so the number can be 32-bit. This fixes compiler failure on 32-bit systems with large block devices. Cc: stable@kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Reviewed-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm exception store: split set_chunk_sizeMikulas Patocka2009-09-041-0/+4
| | | | | | | | | Break the function set_chunk_size to two functions in preparation for the fix in the following patch. Cc: stable@kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm: use i_size_readMikulas Patocka2009-06-221-1/+1
| | | | | | | | | | | | | | | Use i_size_read() instead of reading i_size. If someone changes the size of the device simultaneously, i_size_read is guaranteed to return a valid value (either the old one or the new one). i_size can return some intermediate invalid value (on 32-bit computers with 64-bit i_size, the reads to both halves of i_size can be interleaved with updates to i_size, resulting in garbage being returned). Cc: stable@kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* block: rename CONFIG_LBD to CONFIG_LBDAFBartlomiej Zolnierkiewicz2009-06-191-1/+1
| | | | | | | | | | | | Follow-up to "block: enable by default support for large devices and files on 32-bit archs". Rename CONFIG_LBD to CONFIG_LBDAF to: - allow update of existing [def]configs for "default y" change - reflect that it is used also for large files support nowadays Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* dm snapshot: move status to exception storeJonathan Brassow2009-04-021-2/+3
| | | | | | | | | | | Let the exception store types print out their status through the new API, rather than having the snapshot code do it. Adjust the buffer position to allow for the preceding DMEMIT in the arguments to type->status(). Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: move ctr parsing to exception storeJonathan Brassow2009-04-021-3/+2
| | | | | | | | First step of having the exception stores parse their own arguments - generalizing the interface. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: remove dm_snap header useJonathan Brassow2009-04-021-2/+14
| | | | | | | Move useful functions out of dm-snap.h and stop using dm-snap.h. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm exception store: move cow pointerJonathan Brassow2009-04-021-1/+3
| | | | | | | Move COW device from snapshot to exception store. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm exception store: move chunk_fieldsJonathan Brassow2009-04-021-0/+7
| | | | | | | Move chunk fields from snapshot to exception store. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm exception store: move dm_target pointerJonathan Brassow2009-04-021-1/+2
| | | | | | | Move target pointer from snapshot to exception store. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm exception store: introduce registryJonathan Brassow2009-04-021-5/+14
| | | | | | | Move exception stores into a registry. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm exception store: separate type from instanceJonathan Brassow2009-04-021-2/+11
| | | | | | | Introduce struct dm_exception_store_type. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: extend exception store functionsJonathan Brassow2009-01-061-3/+10
| | | | | | | | | Supply dm_add_exception as a callback to the read_metadata function. Add a status function ready for a later patch and name the functions consistently. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: split out exception store implementationsAlasdair G Kergon2009-01-061-0/+9
| | | | | | | | Move the existing snapshot exception store implementations out into separate files. Later patches will place these behind a new interface in preparation for alternative implementations. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: rename struct exception_storeJonathan Brassow2009-01-061-9/+10
| | | | | | | Rename struct exception_store to dm_exception_store. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* dm snapshot: separate out exception store interfaceJonathan Brassow2009-01-061-0/+131
Pull structures that bridge the gap between snapshot and exception store out of dm-snap.h and put them in a new .h file - dm-exception-store.h. This file will define the API for new exception stores. Ultimately, dm-snap.h is unnecessary, since only dm-snap.c should be using it. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>