user/sven/linux.git/include/linux/device-mapper.h, branch v4.19.229

dm: fix deadlock when swapping to encrypted device

2021-03-04T08:39:57Z

commit a666e5c05e7c4aaabb2c5d58117b0946803d03d2 upstream. The system would deadlock when swapping to a dm-crypt device. The reason is that for each incoming write bio, dm-crypt allocates memory that holds encrypted data. These excessive allocations exhaust all the memory and the result is either deadlock or OOM trigger. This patch limits the number of in-flight swap bios, so that the memory consumed by dm-crypt is limited. The limit is enforced if the target set the "limit_swap_bios" variable and if the bio has REQ_SWAP set. Non-swap bios are not affected becuase taking the semaphore would cause performance degradation. This is similar to request-based drivers - they will also block when the number of requests is over the limit. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm integrity: fix integrity recalculation that is improperly skipped

2020-07-29T08:16:59Z

commit 5df96f2b9f58a5d2dc1f30fe7de75e197f2c25f2 upstream. Commit adc0daad366b62ca1bce3e2958a40b0b71a8b8b3 ("dm: report suspended device during destroy") broke integrity recalculation. The problem is dm_suspended() returns true not only during suspend, but also during resume. So this race condition could occur: 1. dm_integrity_resume calls queue_work(ic->recalc_wq, &ic->recalc_work) 2. integrity_recalc (&ic->recalc_work) preempts the current thread 3. integrity_recalc calls if (unlikely(dm_suspended(ic->ti))) goto unlock_ret; 4. integrity_recalc exits and no recalculating is done. To fix this race condition, add a function dm_post_suspending that is only true during the postsuspend phase and use it instead of dm_suspended(). Signed-off-by: Mikulas Patocka Fixes: adc0daad366b ("dm: report suspended device during destroy") Cc: stable vger kernel org # v4.18+ Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm mpath: fix missing call of path selector type->end_io

2019-09-16T06:22:12Z

[ Upstream commit 5de719e3d01b4abe0de0d7b857148a880ff2a90b ] After commit 396eaf21ee17 ("blk-mq: improve DM's blk-mq IO merging via blk_insert_cloned_request feedback"), map_request() will requeue the tio when issued clone request return BLK_STS_RESOURCE or BLK_STS_DEV_RESOURCE. Thus, if device driver status is error, a tio may be requeued multiple times until the return value is not DM_MAPIO_REQUEUE. That means type->start_io may be called multiple times, while type->end_io is only called when IO complete. In fact, even without commit 396eaf21ee17, setup_clone() failure can also cause tio requeue and associated missed call to type->end_io. The service-time path selector selects path based on in_flight_size, which is increased by st_start_io() and decreased by st_end_io(). Missed calls to st_end_io() can lead to in_flight_size count error and will cause the selector to make the wrong choice. In addition, queue-length path selector will also be affected. To fix the problem, call type->end_io in ->release_clone_rq before tio requeue. map_info is passed to ->release_clone_rq() for map_request() error path that result in requeue. Fixes: 396eaf21ee17 ("blk-mq: improve DM's blk-mq IO merging via blk_insert_cloned_request feedback") Cc: stable@vger.kernl.org Signed-off-by: Yufen Yu Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

dm: fix to_sector() for 32bit

2019-03-23T19:10:09Z

commit 0bdb50c531f7377a9da80d3ce2d61f389c84cb30 upstream. A dm-raid array with devices larger than 4GB won't assemble on a 32 bit host since _check_data_dev_sectors() was added in 4.16. This is because to_sector() treats its argument as an "unsigned long" which is 32bits (4GB) on a 32bit host. Using "unsigned long long" is more correct. Kernels as early as 4.2 can have other problems due to to_sector() being used on the size of a device. Fixes: 0cf4503174c1 ("dm raid: add support for the MD RAID0 personality") cc: stable@vger.kernel.org (v4.2+) Reported-and-tested-by: Guillaume Perréal Signed-off-by: NeilBrown Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dax: Introduce a ->copy_to_iter dax operation

2018-05-23T06:18:31Z

Similar to the ->copy_from_iter() operation, a platform may want to deploy an architecture or device specific routine for handling reads from a dax_device like /dev/pmemX. On x86 this routine will point to a machine check safe version of copy_to_iter(). For now, add the plumbing to device-mapper and the dax core. Cc: Ross Zwisler Cc: Mike Snitzer Cc: Christoph Hellwig Signed-off-by: Dan Williams

Merge tag 'for-4.17/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2018-04-06T18:50:19Z

Pull device mapper updates from Mike Snitzer: - DM core passthrough ioctl fix to retain reference to DM table, and that table's block devices, while issuing the ioctl to one of those block devices. - DM core passthrough ioctl fix to _not_ override the fmode_t used to issue the ioctl. Overriding by using the fmode_t that the block device was originally open with during DM table load is a liability. - Add DM core support for secure erase forwarding and update the DM linear and DM striped targets to support them. - A DM core 4.16 stable fix to allow abnormal IO (e.g. discard, write same, write zeroes) for targets that make use of the non-splitting IO variant (as is done for multipath or thinp when layered directly on NVMe). - Allow DM targets to return a payload in response to a DM message that they are sent. This is useful for DM targets that would like to provide statistics data in response to DM messages. - Update DM bufio to support non-power-of-2 block sizes. Numerous other related changes prepare the DM bufio code for this support. - Fix DM crypt to use a bounded amount of memory across the entire system. This is to avoid OOM that can otherwise occur in response to certain pathological IO workloads (e.g. discarding a large DM crypt device). - Add a 'check_at_most_once' feature to the DM verity target to allow verity to be used on mobile devices that have very limited resources. - Fix the DM integrity target to fail early if a keyed algorithm (e.g. HMAC) is to be used but the key isn't set. - Add non-power-of-2 support to the DM unstripe target. - Eliminate the use of a Variable Length Array in the DM stripe target. - Update the DM log-writes target to record metadata (REQ_META flag). - DM raid fixes for its nosync status and some variable range issues. * tag 'for-4.17/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (28 commits) dm: remove fmode_t argument from .prepare_ioctl hook dm: hold DM table for duration of ioctl rather than use blkdev_get dm raid: fix parse_raid_params() variable range issue dm verity: make verity_for_io_block static dm verity: add 'check_at_most_once' option to only validate hashes once dm bufio: don't embed a bio in the dm_buffer structure dm bufio: support non-power-of-two block sizes dm bufio: use slab cache for dm_buffer structure allocations dm bufio: reorder fields in dm_buffer structure dm bufio: relax alignment constraint on slab cache dm bufio: remove code that merges slab caches dm bufio: get rid of slab cache name allocations dm bufio: move dm-bufio.h to include/linux/ dm bufio: delete outdated comment dm: add support for secure erase forwarding dm: backfill abnormal IO support to non-splitting IO submission dm raid: fix nosync status dm mpath: use DM_MAPIO_SUBMITTED instead of magic number 0 in process_queued_bios() dm stripe: get rid of a Variable Length Array (VLA) dm log writes: record metadata flag for better flags record ...

dm: remove fmode_t argument from .prepare_ioctl hook

2018-04-04T16:12:39Z

Use the fmode_t that is passed to dm_blk_ioctl() rather than inconsistently (varies across targets) drop it on the floor by overriding it with the fmode_t stored in 'struct dm_dev'. All the persistent reservation functions weren't using the fmode_t they got back from .prepare_ioctl so remove them. Signed-off-by: Mike Snitzer

dm: add support for secure erase forwarding

2018-04-03T19:04:21Z

Set QUEUE_FLAG_SECERASE in DM device's queue_flags if a DM table's data devices support secure erase. Also, add support for secure erase to both the linear and striped targets. Signed-off-by: Denis Semakin Signed-off-by: Mike Snitzer

dm: allow targets to return output from messages they are sent

2018-04-03T19:04:10Z

Could be useful for a target to return stats or other information. If a target does DMEMIT() anything to @result from its .message method then it must return 1 to the caller. Signed-off-By: Mike Snitzer

block: Move SECTOR_SIZE and SECTOR_SHIFT definitions into

2018-03-17T20:45:23Z

It happens often while I'm preparing a patch for a block driver that I'm wondering: is a definition of SECTOR_SIZE and/or SECTOR_SHIFT available for this driver? Do I have to introduce definitions of these constants before I can use these constants? To avoid this confusion, move the existing definitions of SECTOR_SIZE and SECTOR_SHIFT into the header file such that these become available for all block drivers. Make the SECTOR_SIZE definition in the uapi msdos_fs.h header file conditional to avoid that including that header file after causes the compiler to complain about a SECTOR_SIZE redefinition. Note: the SECTOR_SIZE / SECTOR_SHIFT / SECTOR_BITS definitions have not been removed from uapi header files nor from NAND drivers in which these constants are used for another purpose than converting block layer offsets and sizes into a number of sectors. Cc: David S. Miller Cc: Mike Snitzer Cc: Dan Williams Cc: Minchan Kim Cc: Nitin Gupta Reviewed-by: Sergey Senozhatsky Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Martin K. Petersen Signed-off-by: Bart Van Assche Signed-off-by: Jens Axboe