• Linus Torvalds's avatar
    Merge tag 'for-5.8/dm-changes' of... · b25c6644
    Linus Torvalds authored
    Merge tag 'for-5.8/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
    
    Pull device mapper updates from Mike Snitzer:
    
     - The largest change for this cycle is the DM zoned target's metadata
       version 2 feature that adds support for pairing regular block devices
       with a zoned device to ease the performance impact associated with
       finite random zones of zoned device.
    
       The changes came in three batches: the first prepared for and then
       added the ability to pair a single regular block device, the second
       was a batch of fixes to improve zoned's reclaim heuristic, and the
       third removed the limitation of only adding a single additional
       regular block device to allow many devices.
    
       Testing has shown linear scaling as more devices are added.
    
     - Add new emulated block size (ebs) target that emulates a smaller
       logical_block_size than a block device supports
    
       The primary use-case is to emulate "512e" devices that have 512 byte
       logical_block_size and 4KB physical_block_size. This is useful to
       some legacy applications that otherwise wouldn't be able to be used
       on 4K devices because they depend on issuing IO in 512 byte
       granularity.
    
     - Add discard interfaces to DM bufio. First consumer of the interface
       is the dm-ebs target that makes heavy use of dm-bufio.
    
     - Fix DM crypt's block queue_limits stacking to not truncate
       logic_block_size.
    
     - Add Documentation for DM integrity's status line.
    
     - Switch DMDEBUG from a compile time config option to instead use
       dynamic debug via pr_debug.
    
     - Fix DM multipath target's hueristic for how it manages
       "queue_if_no_path" state internally.
    
       DM multipath now avoids disabling "queue_if_no_path" unless it is
       actually needed (e.g. in response to configure timeout or explicit
       "fail_if_no_path" message).
    
       This fixes reports of spurious -EIO being reported back to userspace
       application during fault tolerance testing with an NVMe backend.
       Added various dynamic DMDEBUG messages to assist with debugging
       queue_if_no_path in the future.
    
     - Add a new DM multipath "Historical Service Time" Path Selector.
    
     - Fix DM multipath's dm_blk_ioctl() to switch paths on IO error.
    
     - Improve DM writecache target performance by using explicit cache
       flushing for target's single-threaded usecase and a small cleanup to
       remove unnecessary test in persistent_memory_claim.
    
     - Other small cleanups in DM core, dm-persistent-data, and DM
       integrity.
    
    * tag 'for-5.8/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (62 commits)
      dm crypt: avoid truncating the logical block size
      dm mpath: add DM device name to Failing/Reinstating path log messages
      dm mpath: enhance queue_if_no_path debugging
      dm mpath: restrict queue_if_no_path state machine
      dm mpath: simplify __must_push_back
      dm zoned: check superblock location
      dm zoned: prefer full zones for reclaim
      dm zoned: select reclaim zone based on device index
      dm zoned: allocate zone by device index
      dm zoned: support arbitrary number of devices
      dm zoned: move random and sequential zones into struct dmz_dev
      dm zoned: per-device reclaim
      dm zoned: add metadata pointer to struct dmz_dev
      dm zoned: add device pointer to struct dm_zone
      dm zoned: allocate temporary superblock for tertiary devices
      dm zoned: convert to xarray
      dm zoned: add a 'reserved' zone flag
      dm zoned: improve logging messages for reclaim
      dm zoned: avoid unnecessary device recalulation for secondary superblock
      dm zoned: add debugging message for reading superblocks
      ...
    b25c6644
dm-bufio.c 50.3 KB