Commit graph

788 commits

Author SHA1 Message Date
Christoph Hellwig
992ec6a92a dm: remove free_table_devices
free_table_devices just warns and frees all table_device structures when
the target removal did not remove them.  This should never happen, but
if it did, just freeing the structure without deleting them from the
list or cleaning up the resources would not help at all.  So just WARN on
a non-empty list instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Link: https://lore.kernel.org/r/20221115141054.1051801-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-16 15:19:56 -07:00
Genjian Zhang
99f4f5bcb9 dm: remove unnecessary assignment statement in alloc_dev()
Fixes: 74fe6ba923 ("dm: convert to blk_alloc_disk/blk_cleanup_disk")
Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-10-18 17:17:48 -04:00
Mikulas Patocka
43e6c11182 dm: change from DMWARN to DMERR or DMCRIT for fatal errors
Change DMWARN to DMERR in cases when there is an unrecoverable error.
Change DMWARN to DMCRIT when handling of a case is unimplemented.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-10-18 17:16:00 -04:00
Linus Torvalds
6614a3c316 - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe
Lin, Yang Shi, Anshuman Khandual and Mike Rapoport
 
 - Some kmemleak fixes from Patrick Wang and Waiman Long
 
 - DAMON updates from SeongJae Park
 
 - memcg debug/visibility work from Roman Gushchin
 
 - vmalloc speedup from Uladzislau Rezki
 
 - more folio conversion work from Matthew Wilcox
 
 - enhancements for coherent device memory mapping from Alex Sierra
 
 - addition of shared pages tracking and CoW support for fsdax, from
   Shiyang Ruan
 
 - hugetlb optimizations from Mike Kravetz
 
 - Mel Gorman has contributed some pagealloc changes to improve latency
   and realtime behaviour.
 
 - mprotect soft-dirty checking has been improved by Peter Xu
 
 - Many other singleton patches all over the place
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Merge tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Most of the MM queue. A few things are still pending.

  Liam's maple tree rework didn't make it. This has resulted in a few
  other minor patch series being held over for next time.

  Multi-gen LRU still isn't merged as we were waiting for mapletree to
  stabilize. The current plan is to merge MGLRU into -mm soon and to
  later reintroduce mapletree, with a view to hopefully getting both
  into 6.1-rc1.

  Summary:

   - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe
     Lin, Yang Shi, Anshuman Khandual and Mike Rapoport

   - Some kmemleak fixes from Patrick Wang and Waiman Long

   - DAMON updates from SeongJae Park

   - memcg debug/visibility work from Roman Gushchin

   - vmalloc speedup from Uladzislau Rezki

   - more folio conversion work from Matthew Wilcox

   - enhancements for coherent device memory mapping from Alex Sierra

   - addition of shared pages tracking and CoW support for fsdax, from
     Shiyang Ruan

   - hugetlb optimizations from Mike Kravetz

   - Mel Gorman has contributed some pagealloc changes to improve
     latency and realtime behaviour.

   - mprotect soft-dirty checking has been improved by Peter Xu

   - Many other singleton patches all over the place"

 [ XFS merge from hell as per Darrick Wong in

   https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ]

* tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits)
  tools/testing/selftests/vm/hmm-tests.c: fix build
  mm: Kconfig: fix typo
  mm: memory-failure: convert to pr_fmt()
  mm: use is_zone_movable_page() helper
  hugetlbfs: fix inaccurate comment in hugetlbfs_statfs()
  hugetlbfs: cleanup some comments in inode.c
  hugetlbfs: remove unneeded header file
  hugetlbfs: remove unneeded hugetlbfs_ops forward declaration
  hugetlbfs: use helper macro SZ_1{K,M}
  mm: cleanup is_highmem()
  mm/hmm: add a test for cross device private faults
  selftests: add soft-dirty into run_vmtests.sh
  selftests: soft-dirty: add test for mprotect
  mm/mprotect: fix soft-dirty check in can_change_pte_writable()
  mm: memcontrol: fix potential oom_lock recursion deadlock
  mm/gup.c: fix formatting in check_and_migrate_movable_page()
  xfs: fail dax mount if reflink is enabled on a partition
  mm/memcontrol.c: remove the redundant updating of stats_flush_threshold
  userfaultfd: don't fail on unrecognized features
  hugetlb_cgroup: fix wrong hugetlb cgroup numa stat
  ...
2022-08-05 16:32:45 -07:00
Christoph Hellwig
46754bd056 block: move ->bio_split to the gendisk
Only non-passthrough requests are split by the block layer and use the
->bio_split bio_set.  Move it from the request_queue to the gendisk.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220727162300.3089193-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02 21:08:49 -06:00
Christoph Hellwig
5a97806f7d block: change the blk_queue_split calling convention
The double indirect bio leads to somewhat suboptimal code generation.
Instead return the (original or split) bio, and make sure the
request_queue arguments to the lower level helpers is passed after the
bio to avoid constant reshuffling of the argument passing registers.

Also give it and the helpers used to implement it more descriptive names.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220727162300.3089193-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02 17:22:53 -06:00
Linus Torvalds
8374cfe647 - Refactor DM core's mempool allocation so that it clearer by not
being split acorss files.
 
 - Improve DM core's BLK_STS_DM_REQUEUE and BLK_STS_AGAIN handling.
 
 - Optimize DM core's more common bio splitting by eliminating the use
   of bio cloning with bio_split+bio_chain. Shift that cloning cost to
   the relatively unlikely dm_io requeue case that only occurs during
   error handling. Introduces dm_io_rewind() that will clone a bio that
   reflects the subset of the original bio that must be requeued.
 
 - Remove DM core's dm_table_get_num_targets() wrapper and audit all
   dm_table_get_target() callers.
 
 - Fix potential for OOM with DM writecache target by setting a default
   MAX_WRITEBACK_JOBS (set to 256MiB or 1/16 of total system memory,
   whichever is smaller).
 
 - Fix DM writecache target's stats that are reported through
   DM-specific table info.
 
 - Fix use-after-free crash in dm_sm_register_threshold_callback().
 
 - Refine DM core's Persistent Reservation handling in preparation for
   broader work Mike Christie is doing to add compatibility with
   Microsoft Windows Failover Cluster.
 
 - Fix various KASAN reported bugs in the DM raid target.
 
 - Fix DM raid target crash due to md_handle_request() bio splitting
   that recurses to block core without properly initializing the bio's
   bi_dev.
 
 - Fix some code comment typos and fix some Documentation formatting.
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Merge tag 'for-6.0/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Refactor DM core's mempool allocation so that it clearer by not being
   split acorss files.

 - Improve DM core's BLK_STS_DM_REQUEUE and BLK_STS_AGAIN handling.

 - Optimize DM core's more common bio splitting by eliminating the use
   of bio cloning with bio_split+bio_chain. Shift that cloning cost to
   the relatively unlikely dm_io requeue case that only occurs during
   error handling. Introduces dm_io_rewind() that will clone a bio that
   reflects the subset of the original bio that must be requeued.

 - Remove DM core's dm_table_get_num_targets() wrapper and audit all
   dm_table_get_target() callers.

 - Fix potential for OOM with DM writecache target by setting a default
   MAX_WRITEBACK_JOBS (set to 256MiB or 1/16 of total system memory,
   whichever is smaller).

 - Fix DM writecache target's stats that are reported through
   DM-specific table info.

 - Fix use-after-free crash in dm_sm_register_threshold_callback().

 - Refine DM core's Persistent Reservation handling in preparation for
   broader work Mike Christie is doing to add compatibility with
   Microsoft Windows Failover Cluster.

 - Fix various KASAN reported bugs in the DM raid target.

 - Fix DM raid target crash due to md_handle_request() bio splitting
   that recurses to block core without properly initializing the bio's
   bi_dev.

 - Fix some code comment typos and fix some Documentation formatting.

* tag 'for-6.0/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (29 commits)
  dm: fix dm-raid crash if md_handle_request() splits bio
  dm raid: fix address sanitizer warning in raid_resume
  dm raid: fix address sanitizer warning in raid_status
  dm: Start pr_preempt from the same starting path
  dm: Fix PR release handling for non All Registrants
  dm: Start pr_reserve from the same starting path
  dm: Allow dm_call_pr to be used for path searches
  dm: return early from dm_pr_call() if DM device is suspended
  dm thin: fix use-after-free crash in dm_sm_register_threshold_callback
  dm writecache: count number of blocks discarded, not number of discard bios
  dm writecache: count number of blocks written, not number of write bios
  dm writecache: count number of blocks read, not number of read bios
  dm writecache: return void from functions
  dm kcopyd: use __GFP_HIGHMEM when allocating pages
  dm writecache: set a default MAX_WRITEBACK_JOBS
  Documentation: dm writecache: Render status list as list
  Documentation: dm writecache: add blank line before optional parameters
  dm snapshot: fix typo in snapshot_map() comment
  dm raid: remove redundant "the" in parse_raid_params() comment
  dm cache: fix typo in 2 comment blocks
  ...
2022-08-02 14:21:25 -07:00
Mike Snitzer
9dd1cd3220 dm: fix dm-raid crash if md_handle_request() splits bio
Commit ca522482e3 ("dm: pass NULL bdev to bio_alloc_clone")
introduced the optimization to _not_ perform bio_associate_blkg()'s
relatively costly work when DM core clones its bio. But in doing so it
exposed the possibility for DM's cloned bio to alter DM target
behavior (e.g. crash) if a target were to issue IO without first
calling bio_set_dev().

The DM raid target can trigger an MD crash due to its need to split
the DM bio that is passed to md_handle_request(). The split will
recurse to submit_bio_noacct() using a bio with an uninitialized
->bi_blkg. This NULL bio->bi_blkg causes blk_throtl_bio() to
dereference a NULL blkg_to_tg(bio->bi_blkg).

Fix this in DM core by adding a new 'needs_bio_set_dev' target flag that
will make alloc_tio() call bio_set_dev() on behalf of the target.
dm-raid is the only target that requires this flag. bio_set_dev()
initializes the DM cloned bio's ->bi_blkg, using bio_associate_blkg,
before passing the bio to md_handle_request().

Long-term fix would be to audit and refactor MD code to rely on DM to
split its bio, using dm_accept_partial_bio(), but there are MD raid
personalities (e.g. raid1 and raid10) whose implementation are tightly
coupled to handling the bio splitting inline.

Fixes: ca522482e3 ("dm: pass NULL bdev to bio_alloc_clone")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-28 17:36:30 -04:00
Mike Christie
c6adada5b7 dm: Start pr_preempt from the same starting path
pr_preempt has a similar issue as reserve where for all the
reservation types except the All Registrants ones the preempt can
create a reservation. And a follow up reservation or release needs to
go down the same path the preempt did. This has the pr_preempt work
like reserve and release where we always start from the first path in
the first group.

This commit has been tested with windows failover clustering's
validation test and libiscsi's PGR tests to check for regressions.
They both don't have tests to verify this case, so I tested it
manually.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-28 17:29:56 -04:00
Mike Christie
08a3c338e0 dm: Fix PR release handling for non All Registrants
This commit fixes a bug where we are leaving the reservation in place
even though pr_release has run and returned success.

If we have a Write Exclusive, Exclusive Access, or Write/Exclusive
Registrants only reservation, the release must be sent down the path
that is the reservation holder. The problem is multipath_prepare_ioctl
most likely selected path N for the reservation, then later when we do
the release multipath_prepare_ioctl will select a completely different
path. The device will then return success becuase the nvme and scsi
specs say to return success if there is no reservation or if the
release is sent down from a path that is not the holder. We then think
we have released the reservation.

This commit has us loop over each path and send a release so we can
make sure the release is executed on the correct path. It has been
tested with windows failover clustering's validation test which checks
this case, and it has been tested manually (the libiscsi PGR tests
don't have a test case for this yet, but I will be adding one).

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-28 17:29:56 -04:00
Mike Christie
7015108759 dm: Start pr_reserve from the same starting path
When an app does a pr_reserve it will go to whatever path we happen to
be using at the time. This can result in errors when the app does a
second pr_reserve call and expects success but gets a failure because
the reserve is not done on the holder's path. This commit has us
always start trying to do reserves from the first path in the first
group.

Windows failover clustering will produce the type of pattern above.
With this commit, we will now pass its validation test for this case.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-28 17:29:56 -04:00
Mike Christie
8dd87f3c52 dm: Allow dm_call_pr to be used for path searches
The specs state that if you send a reserve down a path that is already
the holder success must be returned and if it goes down a path that
is not the holder reservation conflict must be returned. Windows
failover clustering will send a second reservation and expects that a
device returns success. The problem for multipathing is that for an
All Registrants reservation, we can send the reserve down any path but
for all other reservation types there is one path that is the holder.

To handle this we could add PR state to dm but that can get nasty.
Look at target_core_pr.c for an example of the type of things we'd
have to track. It will also get more complicated because other
initiators can change the state so we will have to add in async
event/sense handling.

This commit, and the 3 commits that follow, tries to keep dm simple
and keep just doing passthrough. This commit modifies dm_call_pr to be
able to find the first usable path that can execute our pr_op then
return. When dm_pr_reserve is converted to dm_call_pr in the next
commit for the normal case we will use the same path for every
reserve.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-28 17:29:56 -04:00
Mike Snitzer
e120a5f1e7 dm: return early from dm_pr_call() if DM device is suspended
Otherwise PR ops may be issued while the broader DM device is being
reconfigured, etc.

Fixes: 9c72bad1f3 ("dm: call PR reserve/unreserve on each underlying device")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-28 17:29:56 -04:00
Shiyang Ruan
8012b86608 dax: introduce holder for dax_device
Patch series "v14 fsdax-rmap + v11 fsdax-reflink", v2.

The patchset fsdax-rmap is aimed to support shared pages tracking for
fsdax.

It moves owner tracking from dax_assocaite_entry() to pmem device driver,
by introducing an interface ->memory_failure() for struct pagemap.  This
interface is called by memory_failure() in mm, and implemented by pmem
device.

Then call holder operations to find the filesystem which the corrupted
data located in, and call filesystem handler to track files or metadata
associated with this page.

Finally we are able to try to fix the corrupted data in filesystem and do
other necessary processing, such as killing processes who are using the
files affected.

The call trace is like this:
memory_failure()
|* fsdax case
|------------
|pgmap->ops->memory_failure()      => pmem_pgmap_memory_failure()
| dax_holder_notify_failure()      =>
|  dax_device->holder_ops->notify_failure() =>
|                                     - xfs_dax_notify_failure()
|  |* xfs_dax_notify_failure()
|  |--------------------------
|  |   xfs_rmap_query_range()
|  |    xfs_dax_failure_fn()
|  |    * corrupted on metadata
|  |       try to recover data, call xfs_force_shutdown()
|  |    * corrupted on file data
|  |       try to recover data, call mf_dax_kill_procs()
|* normal case
|-------------
|mf_generic_kill_procs()


The patchset fsdax-reflink attempts to add CoW support for fsdax, and
takes XFS, which has both reflink and fsdax features, as an example.

One of the key mechanisms needed to be implemented in fsdax is CoW.  Copy
the data from srcmap before we actually write data to the destination
iomap.  And we just copy range in which data won't be changed.

Another mechanism is range comparison.  In page cache case, readpage() is
used to load data on disk to page cache in order to be able to compare
data.  In fsdax case, readpage() does not work.  So, we need another
compare data with direct access support.

With the two mechanisms implemented in fsdax, we are able to make reflink
and fsdax work together in XFS.


This patch (of 14):

To easily track filesystem from a pmem device, we introduce a holder for
dax_device structure, and also its operation.  This holder is used to
remember who is using this dax_device:

 - When it is the backend of a filesystem, the holder will be the
   instance of this filesystem.
 - When this pmem device is one of the targets in a mapped device, the
   holder will be this mapped device.  In this case, the mapped device
   has its own dax_device and it will follow the first rule.  So that we
   can finally track to the filesystem we needed.

The holder and holder_ops will be set when filesystem is being mounted,
or an target device is being activated.

Link: https://lkml.kernel.org/r/20220603053738.1218681-1-ruansy.fnst@fujitsu.com
Link: https://lkml.kernel.org/r/20220603053738.1218681-2-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.wiliams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:30 -07:00
Bart Van Assche
a3282b432f dm/core: Combine request operation type and flags
Improve kernel code uniformity by combining the request operation type and
flags into a single variable. Change 'int rw' into 'enum req_op op' because
the name 'op' is what is used in the block layer to hold a request type.
Use the blk_opf_t and enum req_op types where appropriate to improve static
type checking.

Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-24-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14 12:14:31 -06:00
Bart Van Assche
2d9b02be73 block: Change the type of req_op() and bio_op() into enum req_op
Improve static type checking by changing the type of the value returned by
req_op() and bio_op() from unsigned int into enum req_op. Insert
'default: break;' in switch statements on the enum req_op type to prevent
that the compiler warns about these switch statements.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-5-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14 12:14:30 -06:00
Mike Snitzer
564b5c5476 dm table: audit all dm_table_get_target() callers
All callers of dm_table_get_target() are expected to do proper bounds
checking on the index they pass.

Move dm_table_get_target() to dm-core.h to make it extra clear that only
DM core code should be using it. Switch it to be inlined while at it.

Standardize all DM core callers to use the same for loop pattern and
make associated variables as local as possible. Rename some variables
(e.g. s/table/t/ and s/tgt/ti/) along the way.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-07 11:49:34 -04:00
Mike Snitzer
2aec377a29 dm table: remove dm_table_get_num_targets() wrapper
More efficient and readable to just access table->num_targets directly.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-07 11:49:33 -04:00
Ming Lei
8b211aaccb dm: add two stage requeue mechanism
Commit 61b6e2e532 ("dm: fix BLK_STS_DM_REQUEUE handling when dm_io
represents split bio") reverted DM core's bio splitting back to using
bio_split()+bio_chain() because it was found that otherwise DM's
BLK_STS_DM_REQUEUE would trigger a live-lock waiting for bio
completion that would never occur.

Restore using bio_trim()+bio_inc_remaining(), like was done in commit
7dd76d1fee ("dm: improve bio splitting and associated IO
accounting"), but this time with proper handling for the above
scenario that is covered in more detail in the commit header for
61b6e2e532.

Solve this issue by adding a two staged dm_io requeue mechanism that
uses the new dm_bio_rewind() via dm_io_rewind():

1) requeue the dm_io into the requeue_list added to struct
   mapped_device, and schedule it via new added requeue work. This
   workqueue just clones the dm_io->orig_bio (which DM saves and
   ensures its end sector isn't modified). dm_io_rewind() uses the
   sectors and sectors_offset members of the dm_io that are recorded
   relative to the end of orig_bio: dm_bio_rewind()+bio_trim() are
   then used to make that cloned bio reflect the subset of the
   original bio that is represented by the dm_io that is being
   requeued.

2) the 2nd stage requeue is same with original requeue, but
   io->orig_bio points to new cloned bio (which matches the requeued
   dm_io as described above).

This allows DM core to shift the need for bio cloning from bio-split
time (during IO submission) to the less likely BLK_STS_DM_REQUEUE
handling (after IO completes with that error).

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-07 11:49:32 -04:00
Christoph Hellwig
edd1dbc83b block: use bdev_is_zoned instead of open coding it
Use bdev_is_zoned in all places where a block_device is available instead
of open coding it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220706070350.1703384-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-06 06:46:25 -06:00
Ming Lei
444fe04f7a dm: improve BLK_STS_DM_REQUEUE and BLK_STS_AGAIN handling
If either BLK_STS_DM_REQUEUE or BLK_STS_AGAIN is returned for POLLED
io, we requeue the original bio into deferred list and kick md->wq to
re-submit it to block layer.

Improve the handling in the following way:

1) Factor out dm_handle_requeue() for handling dm_io requeue.

2) Unify handling for BLK_STS_DM_REQUEUE and BLK_STS_AGAIN: clear
   REQ_POLLED for BLK_STS_DM_REQUEUE too, for the sake of simplicity,
   given BLK_STS_DM_REQUEUE is very unusual.

3) Queue md->wq explicitly in dm_handle_requeue(), so requeue handling
   becomes more robust.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-29 14:17:16 -04:00
Christoph Hellwig
e810cb78bc dm: refactor dm_md_mempool allocation
The current split between dm_table_alloc_md_mempools and
dm_alloc_md_mempools is rather arbitrary, so merge the two
into one easy to follow function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-29 12:46:06 -04:00
Christoph Hellwig
8b9ab62662 block: remove blk_cleanup_disk
blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-28 06:33:15 -06:00
Christoph Hellwig
c39493222e dm: open code blk_max_size_offset in max_io_len
max_io_len always passes an explicitly non-zero chunk_sectors into
blk_max_size_offset.  That means much of blk_max_size_offset is not
needed and can be open coded to simplify the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Link: https://lore.kernel.org/r/20220614090934.570632-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27 06:29:11 -06:00
Ming Lei
61b6e2e532 dm: fix BLK_STS_DM_REQUEUE handling when dm_io represents split bio
Commit 7dd76d1fee ("dm: improve bio splitting and associated IO
accounting") removed using cloned bio when dm io splitting is needed.
Using bio_trim()+bio_inc_remaining() rather than bio_split()+bio_chain()
causes multiple dm_io instances to share the same original bio, and it
works fine if IOs are completed successfully.

But a regression was caused for the case when BLK_STS_DM_REQUEUE is
returned from any one of DM's cloned bios (whose dm_io share the same
orig_bio). In this BLK_STS_DM_REQUEUE case only the mapped subset of
the original bio for the current exact dm_io needs to be re-submitted.
However, since the original bio is shared among all dm_io instances,
the ->orig_bio actually only represents the last dm_io instance, so
requeue can't work as expected. Also when more than one dm_io is
requeued, the same original bio is requeued from all dm_io's
completion handler, then race is caused.

Fix this issue by still allocating one clone bio for completing io
only, then io accounting can rely on ->orig_bio being unmodified. This
is needed because the dm_io's sector_offset and sectors members are
recorded relative to an unmodified ->orig_bio.

In the future, we can go back to using bio_trim()+bio_inc_remaining()
for dm's io splitting but then delay needing a bio clone only when
handling BLK_STS_DM_REQUEUE, but that approach is a bit complicated
(so it needs a development cycle):
1) bio clone needs to be done in task context
2) a block interface for unwinding bio is required

Fixes: 7dd76d1fee ("dm: improve bio splitting and associated IO accounting")
Reported-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-23 14:33:13 -04:00
Mike Snitzer
78ccef9123 dm: do not return early from dm_io_complete if BLK_STS_AGAIN without polling
Commit 5291984004 ("dm: fix bio polling to handle possibile
BLK_STS_AGAIN") inadvertently introduced an early return from
dm_io_complete() without first queueing the bio to DM if BLK_STS_AGAIN
occurs and bio-polling is _not_ being used.

Fix this by only returning early from dm_io_complete() if the bio has
first been properly queued to DM. Otherwise, the bio will never finish
via bio_endio.

Fixes: 5291984004 ("dm: fix bio polling to handle possibile BLK_STS_AGAIN")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-21 13:48:52 -04:00
Mikulas Patocka
1ee88de395 dm: fix narrow race for REQ_NOWAIT bios being issued despite no support
Starting with the commit 63a225c9fd20, device mapper has an optimization
that it will take cheaper table lock (dm_get_live_table_fast instead of
dm_get_live_table) if the bio has REQ_NOWAIT. The bios with REQ_NOWAIT
must not block in the target request routine, if they did, we would be
blocking while holding rcu_read_lock, which is prohibited.

The targets that are suitable for REQ_NOWAIT optimization (and that don't
block in the map routine) have the flag DM_TARGET_NOWAIT set. Device
mapper will test if all the targets and all the devices in a table
support nowait (see the function dm_table_supports_nowait) and it will set
or clear the QUEUE_FLAG_NOWAIT flag on its request queue according to
this check.

There's a test in submit_bio_noacct: "if ((bio->bi_opf & REQ_NOWAIT) &&
!blk_queue_nowait(q)) goto not_supported" - this will make sure that
REQ_NOWAIT bios can't enter a request queue that doesn't support them.

This mechanism works to prevent REQ_NOWAIT bios from reaching dm targets
that don't support the REQ_NOWAIT flag (and that may block in the map
routine) - except that there is a small race condition:

submit_bio_noacct checks if the queue has the QUEUE_FLAG_NOWAIT without
holding any locks. Immediatelly after this check, the device mapper table
may be reloaded with a table that doesn't support REQ_NOWAIT (for example,
if we start moving the logical volume or if we activate a snapshot).
However the REQ_NOWAIT bio that already passed the check in
submit_bio_noacct would be sent to device mapper, where it could be
redirected to a dm target that doesn't support REQ_NOWAIT - the result is
sleeping while we hold rcu_read_lock.

In order to fix this race, we double-check if the target supports
REQ_NOWAIT while we hold the table lock (so that the table can't change
under us).

Fixes: 563a225c9f ("dm: introduce dm_{get,put}_live_table_bio called from dm_submit_bio")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-16 19:39:02 -04:00
Mikulas Patocka
5d7362d0d5 dm: fix use-after-free in dm_put_live_table_bio
dm_put_live_table_bio is called from the end of dm_submit_bio.
However, at this point, the bio may be already finished and the caller
may have freed the bio. Consequently, dm_put_live_table_bio accesses
the stale "bio" pointer.

Fix this bug by loading the bi_opf value and passing it to
dm_get_live_table_bio and dm_put_live_table_bio instead of the bio.

This bug was found by running the lvm2 testsuite with kasan.

Fixes: 563a225c9f ("dm: introduce dm_{get,put}_live_table_bio called from dm_submit_bio")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-16 19:38:49 -04:00
Benjamin Marzinski
10eb3a0d51 dm: fix race in dm_start_io_acct
After commit 82f6cdcc36 ("dm: switch dm_io booleans over to proper
flags") dm_start_io_acct stopped atomically checking and setting
was_accounted, which turned into the DM_IO_ACCOUNTED flag. This opened
the possibility for a race where IO accounting is started twice for
duplicate bios. To remove the race, check the flag while holding the
io->lock.

Fixes: 82f6cdcc36 ("dm: switch dm_io booleans over to proper flags")
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-15 11:51:41 -04:00
Mike Snitzer
dddf305640 dm: fix zoned locking imbalance due to needless check in clone_endio
After the commit ca522482e3 ("dm: pass NULL bdev to bio_alloc_clone"),
clone_endio() only calls dm_zone_endio() when DM targets remap the
clone bio's bdev to something other than the md->disk->part0 default.

However, if a DM target (e.g. dm-crypt) stacked ontop of a dm-zoned
does not remap the clone bio using bio_set_dev() then dm_zone_endio()
is not called at completion of the bios and zone locks are not
properly unlocked. This triggers a hang, in dm_zone_map_bio(), when
blktests block/004 is run for dm-crypt on zoned block devices. To
avoid the hang, simply remove the clone_endio() check that verifies
the target remapped the clone bio to a device other than the default.

Fixes: ca522482e3 ("dm: pass NULL bdev to bio_alloc_clone")
Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-10 15:23:54 -04:00
Christoph Hellwig
29dec90a0f dm: fix bio_set allocation
The use of bioset_init_from_src mean that the pre-allocated pools weren't
used for anything except parameter passing, and the integrity pool
creation got completely lost for the actual live mapped_device.  Fix that
by assigning the actual preallocated dm_md_mempools to the mapped_device
and using that for I/O instead of creating new mempools.

Fixes: 2a2a4c510b ("dm: use bioset_init_from_src() to copy bio_set")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-06-08 14:04:14 -04:00
Linus Torvalds
35cdd8656e libnvdimm for 5.19
- Add support for clearing memory error via pwrite(2) on DAX
 
 - Fix 'security overwrite' support in the presence of media errors
 
 - Miscellaneous cleanups and fixes for nfit_test (nvdimm unit tests)
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Merge tag 'libnvdimm-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm and DAX updates from Dan Williams:
 "New support for clearing memory errors when a file is in DAX mode,
  alongside with some other fixes and cleanups.

  Previously it was only possible to clear these errors using a truncate
  or hole-punch operation to trigger the filesystem to reallocate the
  block, now, any page aligned write can opportunistically clear errors
  as well.

  This change spans x86/mm, nvdimm, and fs/dax, and has received the
  appropriate sign-offs. Thanks to Jane for her work on this.

  Summary:

   - Add support for clearing memory error via pwrite(2) on DAX

   - Fix 'security overwrite' support in the presence of media errors

   - Miscellaneous cleanups and fixes for nfit_test (nvdimm unit tests)"

* tag 'libnvdimm-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  pmem: implement pmem_recovery_write()
  pmem: refactor pmem_clear_poison()
  dax: add .recovery_write dax_operation
  dax: introduce DAX_RECOVERY_WRITE dax access mode
  mce: fix set_mce_nospec to always unmap the whole page
  x86/mce: relocate set{clear}_mce_nospec() functions
  acpi/nfit: rely on mce->misc to determine poison granularity
  testing: nvdimm: asm/mce.h is not needed in nfit.c
  testing: nvdimm: iomap: make __nfit_test_ioremap a macro
  nvdimm: Allow overwrite in the presence of disabled dimms
  tools/testing/nvdimm: remove unneeded flush_workqueue
2022-05-27 15:49:30 -07:00
Jane Chu
047218ec90 dax: add .recovery_write dax_operation
Introduce dax_recovery_write() operation. The function is used to
recover a dax range that contains poison. Typical use case is when
a user process receives a SIGBUS with si_code BUS_MCEERR_AR
indicating poison(s) in a dax range, in response, the user process
issues a pwrite() to the page-aligned dax range, thus clears the
poison and puts valid data in the range.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Link: https://lore.kernel.org/r/20220422224508.440670-6-jane.chu@oracle.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-05-16 13:37:59 -07:00
Jane Chu
e511c4a3d2 dax: introduce DAX_RECOVERY_WRITE dax access mode
Up till now, dax_direct_access() is used implicitly for normal
access, but for the purpose of recovery write, dax range with
poison is requested.  To make the interface clear, introduce
	enum dax_access_mode {
		DAX_ACCESS,
		DAX_RECOVERY_WRITE,
	}
where DAX_ACCESS is used for normal dax access, and
DAX_RECOVERY_WRITE is used for dax recovery write.

Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Link: https://lore.kernel.org/r/165247982851.52965.11024212198889762949.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-05-16 13:35:56 -07:00
Mike Snitzer
ca522482e3 dm: pass NULL bdev to bio_alloc_clone
Most DM targets will remap the clone bio passed to their ->map
function using bio_set_bdev(). So this change to pass NULL bdev to
bio_alloc_clone avoids clone-time work that sets up resources for a
bdev association that will not be used in practice (e.g. clone issued
to underlying device will not use DM device's blk-cgroups resources).

But clone->bi_bdev is still initialized following bio_alloc_clone to
preserve DM target expectations that clone->bi_bdev will be set.
Follow-up work is needed to audit DM targets to remove accesses to a
clone->bi_bdev that the target didn't initialize with bio_set_dev().

Depends-on: 7ecc56c62b ("block: allow passing a NULL bdev to bio_alloc_clone/bio_init_clone")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-11 13:58:52 -04:00
Mike Snitzer
4edadf6dcb dm: improve abnormal bio processing
Read/write/flush are the most common operations, optimize switch in
is_abnormal_io() for those cases. Follows same pattern established in
block perf-wip commit ("block: optimise blk_may_split for normal rw")

Also, push is_abnormal_io() check and blk_queue_split() down from
dm_submit_bio() to dm_split_and_process_bio() and set new
'is_abnormal_io' flag in clone_info. Optimize __split_and_process_bio
and __process_abnormal_io by leveraging ci.is_abnormal_io flag.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:36 -04:00
Mike Snitzer
9d20653fe8 dm: simplify bio-based IO accounting further
Now that io splitting is recorded prior to, or during, ->map IO
accounting can happen immediately rather than defer until after
bio splitting in dm_split_and_process_bio().

Remove the DM_IO_START_ACCT flag and also remove dm_io's map_task
member because there is no longer any need to wait for splitting to
occur before accounting.

Also move dm_io struct's 'flags' member to consolidate struct holes.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:36 -04:00
Ming Lei
ec211631ae dm: put all polled dm_io instances into a single list
Now that bio_split() isn't used by DM's bio splitting, it is a bit
overkill to link dm_io into an hlist given there is only single dm_io
in the list.

Convert to using a single list for holding all dm_io instances
associated with this bio.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:36 -04:00
Ming Lei
0f14d60a02 dm: improve dm_io reference counting
Currently each dm_io's reference counter is grabbed before calling
__map_bio(), this way isn't efficient since we can move this grabbing
to initialization time inside alloc_io().

Meantime it becomes typical async io reference counter model: one is
for submission side, the other is for completion side, and the io won't
be completed until both sides are done.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:36 -04:00
Ming Lei
2e803cd99b dm: don't grab target io reference in dm_zone_map_bio
dm_zone_map_bio() is only called from __map_bio in which the io's
reference is grabbed already, and the reference won't be released
until the bio is submitted, so not necessary to do it dm_zone_map_bio
any more.

Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:36 -04:00
Ming Lei
7dd76d1fee dm: improve bio splitting and associated IO accounting
The current DM code (ab)uses late assignment of dm_io->orig_bio (after
__map_bio() returns and any bio splitting is complete) to indicate the
FS bio has been processed and can be accounted. This results in
awkward waiting until ->orig_bio is set in dm_submit_bio_remap().

Also the bio splitting was implemented using bio_split()+bio_chain()
-- a well-worn pattern but it requires bio cloning purely for the
benefit of more natural IO accounting.  The bio_split() result was
stored in ->orig_bio to represent the mapped part of the original FS
bio.

DM has switched to the bdev based IO accounting interface.  DM's IO
accounting can be implemented in terms of the original FS bio (now
stored early in ->orig_bio) via access to its sectors/bio_op. And
if/when splitting is needed, set a new DM_IO_WAS_SPLIT flag and use
new dm_io fields of .sector_offset & .sectors to allow IO accounting
for split bios _without_ needing to clone a new bio to store in
->orig_bio.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Co-developed-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:35 -04:00
Ming Lei
d3de6d1269 dm: switch to bdev based IO accounting interfaces
DM splits flush with data into empty flush followed by bio with data
payload, switch dm_io_acct() to use bdev_{start,end}_io_acct() to do
this accoiunting more naturally (rather than temporarily changing the
bio's bi_size).

This will allow DM to more easily account bios that are split (in
following commit).

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:35 -04:00
Ming Lei
e6926ad0c9 dm: pass dm_io instance to dm_io_acct directly
All the other 4 parameters are retrieved from the 'dm_io' instance, so
it's not necessary to pass all four to dm_io_acct().

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:35 -04:00
Ming Lei
b992b40dfc dm: don't pass bio to __dm_start_io_acct and dm_end_io_acct
dm->orig_bio is always passed to __dm_start_io_acct and dm_end_io_acct,
so it isn't necessary to take one bio parameter for the two helpers.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:35 -04:00
Mike Snitzer
bdb34759a0 dm: use bio_sectors in dm_aceept_partial_bio
Rename 'bi_size' to 'bio_sectors' given bi_size is being stored in
sectors.  Also, use bio_sectors() rather than open-coding it.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:35 -04:00
Mike Snitzer
442761fd2b dm: conditionally enable branching for less used features
Use jump_labels to further reduce cost of unlikely branches for zoned
block devices, dm-stats and swap_bios throttling.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:34 -04:00
Mike Snitzer
563a225c9f dm: introduce dm_{get,put}_live_table_bio called from dm_submit_bio
If a bio is marked REQ_NOWAIT optimize dm_submit_bio()'s dm_table RCU
usage to dm_{get,put}_live_table_fast.

DM core offers protection against blocking (via suspend) if REQ_NOWAIT.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:34 -04:00
Mike Snitzer
6cbce280fc dm: add local variables to clone_endio and __map_bio
Avoid redundant dereferences in both functions.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:34 -04:00
Mike Snitzer
fe221db419 dm: mark various branches unlikely
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:34 -04:00
Mike Snitzer
3b03f7c124 dm: simplify dm_start_io_acct
Pull common DM_IO_ACCOUNTED check out to beginning of dm_start_io_acct.
Also, use dm_tio_is_normal (and move it to dm-core.h).

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:34 -04:00