1. 27 Jun, 2017 1 commit
    • Vallish Vaidyeshwara's avatar
      dm thin: do not queue freed thin mapping for next stage processing · 00a0ea33
      Vallish Vaidyeshwara authored
      
      
      process_prepared_discard_passdown_pt1() should cleanup
      dm_thin_new_mapping in cases of error.
      
      dm_pool_inc_data_range() can fail trying to get a block reference:
      
      metadata operation 'dm_pool_inc_data_range' failed: error = -61
      
      When dm_pool_inc_data_range() fails, dm thin aborts current metadata
      transaction and marks pool as PM_READ_ONLY. Memory for thin mapping
      is released as well. However, current thin mapping will be queued
      onto next stage as part of queue_passdown_pt2() or passdown_endio().
      This dangling thin mapping memory when processed and accessed in
      next stage will lead to device mapper crashing.
      
      Code flow without fix:
      -> process_prepared_discard_passdown_pt1(m)
         -> dm_thin_remove_range()
         -> discard passdown
            --> passdown_endio(m) queues m onto next stage
         -> dm_pool_inc_data_range() fails, frees memory m
                  but does not remove it from next stage queue
      
      -> process_prepared_discard_passdown_pt2(m)
         -> processes freed memory m and crashes
      
      One such stack:
      
      Call Trace:
      [<ffffffffa037a46f>] dm_cell_release_no_holder+0x2f/0x70 [dm_bio_prison]
      [<ffffffffa039b6dc>] cell_defer_no_holder+0x3c/0x80 [dm_thin_pool]
      [<ffffffffa039b88b>] process_prepared_discard_passdown_pt2+0x4b/0x90 [dm_thin_pool]
      [<ffffffffa0399611>] process_prepared+0x81/0xa0 [dm_thin_pool]
      [<ffffffffa039e735>] do_worker+0xc5/0x820 [dm_thin_pool]
      [<ffffffff8152bf54>] ? __schedule+0x244/0x680
      [<ffffffff81087e72>] ? pwq_activate_delayed_work+0x42/0xb0
      [<ffffffff81089f53>] process_one_work+0x153/0x3f0
      [<ffffffff8108a71b>] worker_thread+0x12b/0x4b0
      [<ffffffff8108a5f0>] ? rescuer_thread+0x350/0x350
      [<ffffffff8108fd6a>] kthread+0xca/0xe0
      [<ffffffff8108fca0>] ? kthread_park+0x60/0x60
      [<ffffffff81530b45>] ret_from_fork+0x25/0x30
      
      The fix is to first take the block ref count for discarded block and
      then do a passdown discard of this block. If block ref count fails,
      then bail out aborting current metadata transaction, mark pool as
      PM_READ_ONLY and also free current thin mapping memory (existing error
      handling code) without queueing this thin mapping onto next stage of
      processing. If block ref count succeeds, then passdown discard of this
      block. Discard callback of passdown_endio() will queue this thin mapping
      onto next stage of processing.
      
      Code flow with fix:
      -> process_prepared_discard_passdown_pt1(m)
         -> dm_thin_remove_range()
         -> dm_pool_inc_data_range()
            --> if fails, free memory m and bail out
         -> discard passdown
            --> passdown_endio(m) queues m onto next stage
      
      Cc: stable <stable@vger.kernel.org> # v4.9+
      Reviewed-by: default avatarEduardo Valentin <eduval@amazon.com>
      Reviewed-by: default avatarCristian Gafton <gafton@amazon.com>
      Reviewed-by: default avatarAnchal Agarwal <anchalag@amazon.com>
      Signed-off-by: default avatarVallish Vaidyeshwara <vallish@amazon.com>
      Reviewed-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      00a0ea33
  2. 24 Apr, 2017 1 commit
    • Dennis Yang's avatar
      dm thin: fix a memory leak when passing discard bio down · 948f581a
      Dennis Yang authored
      
      
      dm-thin does not free the discard_parent bio after all chained sub
      bios finished. The following kmemleak report could be observed after
      pool with discard_passdown option processes discard bios in
      linux v4.11-rc7. To fix this, we drop the discard_parent bio reference
      when its endio (passdown_endio) called.
      
      unreferenced object 0xffff8803d6b29700 (size 256):
        comm "kworker/u8:0", pid 30349, jiffies 4379504020 (age 143002.776s)
        hex dump (first 32 bytes):
          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
          01 00 00 00 00 00 00 f0 00 00 00 00 00 00 00 00  ................
        backtrace:
          [<ffffffff81a5efd9>] kmemleak_alloc+0x49/0xa0
          [<ffffffff8114ec34>] kmem_cache_alloc+0xb4/0x100
          [<ffffffff8110eec0>] mempool_alloc_slab+0x10/0x20
          [<ffffffff8110efa5>] mempool_alloc+0x55/0x150
          [<ffffffff81374939>] bio_alloc_bioset+0xb9/0x260
          [<ffffffffa018fd20>] process_prepared_discard_passdown_pt1+0x40/0x1c0 [dm_thin_pool]
          [<ffffffffa018b409>] break_up_discard_bio+0x1a9/0x200 [dm_thin_pool]
          [<ffffffffa018b484>] process_discard_cell_passdown+0x24/0x40 [dm_thin_pool]
          [<ffffffffa018b24d>] process_discard_bio+0xdd/0xf0 [dm_thin_pool]
          [<ffffffffa018ecf6>] do_worker+0xa76/0xd50 [dm_thin_pool]
          [<ffffffff81086239>] process_one_work+0x139/0x370
          [<ffffffff810867b1>] worker_thread+0x61/0x450
          [<ffffffff8108b316>] kthread+0xd6/0xf0
          [<ffffffff81a6cd1f>] ret_from_fork+0x3f/0x70
          [<ffffffffffffffff>] 0xffffffffffffffff
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarDennis Yang <dennisyang@qnap.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      948f581a
  3. 08 Apr, 2017 1 commit
  4. 07 Mar, 2017 1 commit
  5. 02 Feb, 2017 1 commit
  6. 27 Jan, 2017 1 commit
  7. 07 Aug, 2016 1 commit
    • Jens Axboe's avatar
      block: rename bio bi_rw to bi_opf · 1eff9d32
      Jens Axboe authored
      Since commit 63a4cc24
      
      , bio->bi_rw contains flags in the lower
      portion and the op code in the higher portions. This means that
      old code that relies on manually setting bi_rw is most likely
      going to be broken. Instead of letting that brokeness linger,
      rename the member, to force old and out-of-tree code to break
      at compile time instead of at runtime.
      
      No intended functional changes in this commit.
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      1eff9d32
  8. 20 Jul, 2016 1 commit
  9. 07 Jun, 2016 4 commits
  10. 13 May, 2016 3 commits
  11. 05 May, 2016 1 commit
  12. 11 Mar, 2016 1 commit
    • Mike Snitzer's avatar
      dm thin: consistently return -ENOSPC if pool has run out of data space · c3667cc6
      Mike Snitzer authored
      Commit 0a927c2f
      
       ("dm thin: return -ENOSPC when erroring retry list due
      to out of data space") was a step in the right direction but didn't go
      far enough.
      
      Add a new 'out_of_data_space' flag to 'struct pool' and set it if/when
      the pool runs of of data space.  This fixes cell_error() and
      error_retry_list() to not blindly return -EIO.
      
      We cannot rely on the 'error_if_no_space' feature flag since it is
      transient (in that it can be reset once space is added, plus it only
      controls whether errors are issued, it doesn't reflect whether the
      pool is actually out of space).
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      c3667cc6
  13. 23 Feb, 2016 1 commit
  14. 07 Jan, 2016 1 commit
  15. 17 Dec, 2015 1 commit
    • Nikolay Borisov's avatar
      dm thin: fix race condition when destroying thin pool workqueue · 18d03e8c
      Nikolay Borisov authored
      When a thin pool is being destroyed delayed work items are
      cancelled using cancel_delayed_work(), which doesn't guarantee that on
      return the delayed item isn't running.  This can cause the work item to
      requeue itself on an already destroyed workqueue.  Fix this by using
      cancel_delayed_work_sync() which guarantees that on return the work item
      is not running anymore.
      
      Fixes: 905e51b3 ("dm thin: commit outstanding data every second")
      Fixes: 85ad643b
      
       ("dm thin: add timeout to stop out-of-data-space mode holding IO forever")
      Signed-off-by: default avatarNikolay Borisov <kernel@kyup.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Cc: stable@vger.kernel.org
      18d03e8c
  16. 23 Nov, 2015 1 commit
    • Mike Snitzer's avatar
      dm thin: fix regression in advertised discard limits · 0fcb04d5
      Mike Snitzer authored
      When establishing a thin device's discard limits we cannot rely on the
      underlying thin-pool device's discard capabilities (which are inherited
      from the thin-pool's underlying data device) given that DM thin devices
      must provide discard support even when the thin-pool's underlying data
      device doesn't support discards.
      
      Users were exposed to this thin device discard limits regression if
      their thin-pool's underlying data device does _not_ support discards.
      This regression caused all upper-layers that called the
      blkdev_issue_discard() interface to not be able to issue discards to
      thin devices (because discard_granularity was 0).  This regression
      wasn't caught earlier because the device-mapper-test-suite's extensive
      'thin-provisioning' discard tests are only ever performed against
      thin-pool's with data devices that support discards.
      
      Fix is to have thin_io_hints() test the pool's 'discard_enabled' feature
      rather than inferring whether or not a thin device's discard support
      should be enabled by looking at the thin-pool's discard_granularity.
      
      Fixes: 21607670
      
       ("dm thin: disable discard support for thin devices if pool's is disabled")
      Reported-by: default avatarMike Gerber <mike@sprachgewalt.de>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Cc: stable@vger.kernel.org # 4.1+
      0fcb04d5
  17. 16 Nov, 2015 1 commit
    • Mike Snitzer's avatar
      dm thin: restore requested 'error_if_no_space' setting on OODS to WRITE transition · 172c2386
      Mike Snitzer authored
      
      
      A thin-pool that is in out-of-data-space (OODS) mode may transition back
      to write mode -- without the admin adding more space to the thin-pool --
      if/when blocks are released (either by deleting thin devices or
      discarding provisioned blocks).
      
      But as part of the thin-pool's earlier transition to out-of-data-space
      mode the thin-pool may have set the 'error_if_no_space' flag to true if
      the no_space_timeout expires without more space having been made
      available.  That implementation detail, of changing the pool's
      error_if_no_space setting, needs to be reset back to the default that
      the user specified when the thin-pool's table was loaded.
      
      Otherwise we'll drop the user requested behaviour on the floor when this
      out-of-data-space to write mode transition occurs.
      Reported-by: default avatarVivek Goyal <vgoyal@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Acked-by: default avatarJoe Thornber <ejt@redhat.com>
      Fixes: 2c43fd26 ("dm thin: fix missing out-of-data-space to write mode transition if blocks are released")
      Cc: stable@vger.kernel.org
      172c2386
  18. 13 Oct, 2015 1 commit
  19. 14 Sep, 2015 1 commit
  20. 18 Aug, 2015 1 commit
  21. 13 Aug, 2015 1 commit
    • Kent Overstreet's avatar
      block: kill merge_bvec_fn() completely · 8ae12666
      Kent Overstreet authored
      
      
      As generic_make_request() is now able to handle arbitrarily sized bios,
      it's no longer necessary for each individual block driver to define its
      own ->merge_bvec_fn() callback. Remove every invocation completely.
      
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
      Cc: drbd-user@lists.linbit.com
      Cc: Jiri Kosina <jkosina@suse.cz>
      Cc: Yehuda Sadeh <yehuda@inktank.com>
      Cc: Sage Weil <sage@inktank.com>
      Cc: Alex Elder <elder@kernel.org>
      Cc: ceph-devel@vger.kernel.org
      Cc: Alasdair Kergon <agk@redhat.com>
      Cc: Mike Snitzer <snitzer@redhat.com>
      Cc: dm-devel@redhat.com
      Cc: Neil Brown <neilb@suse.de>
      Cc: linux-raid@vger.kernel.org
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
      Acked-by: NeilBrown <neilb@suse.de> (for the 'md' bits)
      Acked-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
      [dpark: also remove ->merge_bvec_fn() in dm-thin as well as
       dm-era-target, and resolve merge conflicts]
      Signed-off-by: default avatarDongsu Park <dpark@posteo.net>
      Signed-off-by: default avatarMing Lin <ming.l@ssi.samsung.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      8ae12666
  22. 29 Jul, 2015 1 commit
    • Christoph Hellwig's avatar
      block: add a bi_error field to struct bio · 4246a0b6
      Christoph Hellwig authored
      
      
      Currently we have two different ways to signal an I/O error on a BIO:
      
       (1) by clearing the BIO_UPTODATE flag
       (2) by returning a Linux errno value to the bi_end_io callback
      
      The first one has the drawback of only communicating a single possible
      error (-EIO), and the second one has the drawback of not beeing persistent
      when bios are queued up, and are not passed along from child to parent
      bio in the ever more popular chaining scenario.  Having both mechanisms
      available has the additional drawback of utterly confusing driver authors
      and introducing bugs where various I/O submitters only deal with one of
      them, and the others have to add boilerplate code to deal with both kinds
      of error returns.
      
      So add a new bi_error field to store an errno value directly in struct
      bio and remove the existing mechanisms to clean all this up.
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Reviewed-by: default avatarNeilBrown <neilb@suse.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      4246a0b6
  23. 26 Jul, 2015 1 commit
  24. 16 Jul, 2015 2 commits
    • Mike Snitzer's avatar
      dm thin: display 'needs_check' in status if it is set · e4c78e21
      Mike Snitzer authored
      
      
      There is currently no way to see that the needs_check flag has been set
      in the metadata.  Display 'needs_check' in the thin-pool status if it is
      set in the thinp metadata.
      
      Also, update thinp documentation.
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      e4c78e21
    • Mike Snitzer's avatar
      dm thin: stay in out-of-data-space mode once no_space_timeout expires · bcc696fa
      Mike Snitzer authored
      
      
      This fixes an issue where running out of data space would cause the
      thin-pool's metadata to become read-only.  There was no reason to make
      metadata read-only -- calling set_pool_mode() with PM_READ_ONLY was a
      misguided way to error all queued and future write IOs.  We can
      accomplish the same by degrading from PM_OUT_OF_DATA_SPACE to
      PM_OUT_OF_DATA_SPACE with error_if_no_space enabled.
      
      Otherwise, the use of PM_READ_ONLY could cause a race where commit() was
      started before the PM_READ_ONLY transition but dm_pool_commit_metadata()
      would go on to fail because the block manager had transitioned to
      read-only.  The return of -EPERM from dm_pool_commit_metadata(), due to
      attempting to commit while in read-only mode, caused the thin-pool to
      set 'needs_check' because a metadata_operation_failed().  This needless
      cascade of failures makes life for users more difficult than needed.
      Reported-by: default avatarVivek Goyal <vgoyal@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      bcc696fa
  25. 06 Jul, 2015 1 commit
  26. 11 Jun, 2015 2 commits
    • Mike Snitzer's avatar
      dm thin: fail messages with EOPNOTSUPP when pool cannot handle messages · fd467696
      Mike Snitzer authored
      
      
      Use EOPNOTSUPP, rather than EINVAL, error code when user attempts to
      send the pool a message.  Otherwise usespace is led to believe the
      message failed due to invalid argument.
      Reported-by: default avatarZdenek Kabelac <zkabelac@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      fd467696
    • Joe Thornber's avatar
      dm thin: range discard support · 34fbcf62
      Joe Thornber authored
      
      
      Previously REQ_DISCARD bios have been split into block sized chunks
      before submission to the thin target.  There are a couple of issues with
      this:
      
       - If the block size is small, a large discard request can
         get broken up into a great many bios which is both slow and causes
         a lot of memory pressure.
      
       - The thin pool block size and the discard granularity for the
         underlying data device need to be compatible if we want to passdown
         the discard.
      
      This patch relaxes the block size granularity for thin devices.  It
      makes use of the recent range locking added to the bio_prison to
      quiesce a whole range of thin blocks before unmapping them.  Once a
      thin range has been unmapped the discard can then be passed down to
      the data device for those sub ranges where the data blocks are no
      longer used (ie. they weren't shared in the first place).
      
      This patch also doesn't make any apologies about open-coding portions
      of block core as a means to supporting async discard completions in the
      near-term -- if/when late bio splitting lands it'll all get cleaned up.
      Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      34fbcf62
  27. 29 May, 2015 2 commits
  28. 22 May, 2015 1 commit
    • Mike Snitzer's avatar
      block: remove management of bi_remaining when restoring original bi_end_io · 326e1dbb
      Mike Snitzer authored
      Commit c4cf5261 ("bio: skip atomic inc/dec of ->bi_remaining for
      non-chains") regressed all existing callers that followed this pattern:
       1) saving a bio's original bi_end_io
       2) wiring up an intermediate bi_end_io
       3) restoring the original bi_end_io from intermediate bi_end_io
       4) calling bio_endio() to execute the restored original bi_end_io
      
      The regression was due to BIO_CHAIN only ever getting set if
      bio_inc_remaining() is called.  For the above pattern it isn't set until
      step 3 above (step 2 would've needed to establish BIO_CHAIN).  As such
      the first bio_endio(), in step 2 above, never decremented __bi_remaining
      before calling the intermediate bi_end_io -- leaving __bi_remaining with
      the value 1 instead of 0.  When bio_inc_remaining() occurred during step
      3 it brought it to a value of 2.  When the second bio_endio() was
      called, in step 4 above, it should've called the original bi_end_io but
      it didn't because there was an extra reference that wasn't dropped (due
      to atomic operations being optimized away since BIO_CHAIN wasn't set
      upfront).
      
      Fix this issue by removing the __bi_remaining management complexity for
      all callers that use the above pattern -- bio_chain() is the only
      interface that _needs_ to be concerned with __bi_remaining.  For the
      above pattern callers just expect the bi_end_io they set to get called!
      Remove bio_endio_nodec() and also remove all bio_inc_remaining() calls
      that aren't associated with the bio_chain() interface.
      
      Also, the bio_inc_remaining() interface has been moved local to bio.c.
      
      Fixes: c4cf5261
      
       ("bio: skip atomic inc/dec of ->bi_remaining for non-chains")
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Reviewed-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      326e1dbb
  29. 05 May, 2015 1 commit
  30. 27 Feb, 2015 1 commit
    • Joe Thornber's avatar
      dm thin: fix to consistently zero-fill reads to unprovisioned blocks · 5f027a3b
      Joe Thornber authored
      
      
      It was always intended that a read to an unprovisioned block will return
      zeroes regardless of whether the pool is in read-only or read-write
      mode.  thin_bio_map() was inconsistent with its handling of such reads
      when the pool is in read-only mode, it now properly zero-fills the bios
      it returns in response to unprovisioned block reads.
      
      Eliminate thin_bio_map()'s special read-only mode handling of -ENODATA
      and just allow the IO to be deferred to the worker which will result in
      pool->process_bio() handling the IO (which already properly zero-fills
      reads to unprovisioned blocks).
      Reported-by: default avatarEric Sandeen <sandeen@redhat.com>
      Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Cc: stable@vger.kernel.org
      5f027a3b
  31. 09 Feb, 2015 1 commit
  32. 28 Jan, 2015 1 commit