Commit Graph

776 Commits

Author SHA1 Message Date
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
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
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
Mike Snitzer
4857abf664 dm: simplify dm_io access in dm_split_and_process_bio
Use local variable instead of redudant access using ci.io

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:33 -04:00
Mike Snitzer
84b98f4ce4 dm: factor out dm_io_set_error and __dm_io_dec_pending
Also eliminate need to use errno_to_blk_status().

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:33 -04:00
Mike Snitzer
cfc97abcbe dm: conditionally enable BIOSET_PERCPU_CACHE for dm_io bioset
A bioset's per-cpu alloc cache may have broader utility in the future
but for now constrain it to being tightly coupled to QUEUE_FLAG_POLL.

Also change dm_io_complete() to use bio_clear_polled() so that it
properly clears all associated bio state on requeue.

This commit improves DM's hipri bio polling (REQ_POLLED) perf by
7 - 20% depending on the system.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-05-05 17:31:33 -04:00
Christoph Hellwig
70200574cc block: remove QUEUE_FLAG_DISCARD
Just use a non-zero max_discard_sectors as an indicator for discard
support, similar to what is done for write zeroes.

The only places where needs special attention is the RAID5 driver,
which must clear discard support for security reasons by default,
even if the default stacking rules would allow for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-17 19:49:59 -06:00
Shin'ichiro Kawasaki
92b914e29a dm: fix bio length of empty flush
The commit 92986f6b4c ("dm: use bio_clone_fast in alloc_io/alloc_tio")
removed bio_clone_fast() call from alloc_tio() when ci->io->tio is
available. In this case, ci->bio is not copied to ci->io->tio.clone.
This is fine since init_clone_info() sets same values to ci->bio and
ci->io->tio.clone.

However, when incoming bios have REQ_PREFLUSH flag, __send_empty_flush()
prepares a zero length bio on stack and set it to ci->bio. At this time,
ci->io->tio.clone still keeps non-zero length. When alloc_tio() chooses
this ci->io->tio.clone as the bio to map, it is passed to targets as
non-empty flush bio. It causes bio length check failure in dm-zoned and
unexpected operation such as dm_accept_partial_bio() call.

To avoid the non-empty flush bio, set zero length to ci->io->tio.clone
in __send_empty_flush().

Fixes: 92986f6b4c ("dm: use bio_clone_fast in alloc_io/alloc_tio")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-04-15 16:16:09 -04:00
Mike Snitzer
7dd06a2548 dm: allow dm_accept_partial_bio() for dm_io without duplicate bios
The intent behind commit e6fc9f62ce ("dm: flag clones created by
__send_duplicate_bios") was to formally disallow the use of
dm_accept_partial_bio() where it simply isn't possible -- due to
constraint that multiple bios cannot meaningfully update a shared
tio->len_ptr.

But that commit went too far and disallowed the case where "abormal"
IO (e.g. WRITE_ZEROES) is only using a single bio.  Fix this by
not marking a dm_io with a single dm_target_io (and bio), that happens
to be created by __send_duplicate_bios, as DM_TIO_IS_DUPLICATE_BIO.
Also remove 'unsigned *len' parameter from alloc_multiple_bios().

This commit fixes a dm_accept_partial_bio() BUG_ON() with dm-zoned
when a WRITE_ZEROES bio is issued.

Fixes: 655f3aad7a ("dm: switch dm_target_io booleans over to proper flags")
Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-04-14 20:01:54 -04:00
Ming Lei
5291984004 dm: fix bio polling to handle possibile BLK_STS_AGAIN
Expanded testing of DM's bio polling support (using more fio threads
to dm-linear ontop of null_blk) exposed the possibility for polled
bios to hang (repeatedly polling in io_uring) when null_blk responds
with BLK_STS_AGAIN (due to lack of resources):

1) io_complete_rw_iopoll() is called from blkdev_bio_end_io_async() to
   notify kiocb is done, that is the completion interface between block
   layer and io_uring

2) io_complete_rw_iopoll() is called from io_do_iopoll()

3) dm returns BLK_STS_AGAIN for one bio (on behalf of underlying
   driver), then io_complete_rw_iopoll is called, but io_do_iopoll()
   doesn't handle -EAGAIN at all (due to logic in io_rw_should_reissue)

4) reason for dm's BLK_STS_AGAIN is underlying null_blk driver ran out
   of requests (easier to reproduce by setting low hw_queue_depth).

5) dm should handle BLK_STS_AGAIN for POLLED underlying IO, and may
   retry in dm layer.

This fix adds REQ_POLLED specific BLK_STS_AGAIN handling to
dm_io_complete() that clears REQ_POLLED and requeues the bio to DM
using queue_io().

Fixes: b99fdcdc36 ("dm: support bio polling")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
[snitzer: revised header, reused dm_io_complete's REQ_POLLED case]
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-04-01 13:23:12 -04:00
Linus Torvalds
6f2689a766 SCSI misc on 20220324
This series consists of the usual driver updates (qla2xxx, pm8001,
 libsas, smartpqi, scsi_debug, lpfc, iscsi, mpi3mr) plus minor updates
 and bug fixes.  The high blast radius core update is the removal of
 write same, which affects block and several non-SCSI devices.  The
 other big change, which is more local, is the removal of the SCSI
 pointer.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This series consists of the usual driver updates (qla2xxx, pm8001,
  libsas, smartpqi, scsi_debug, lpfc, iscsi, mpi3mr) plus minor updates
  and bug fixes.

  The high blast radius core update is the removal of write same, which
  affects block and several non-SCSI devices. The other big change,
  which is more local, is the removal of the SCSI pointer"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (281 commits)
  scsi: scsi_ioctl: Drop needless assignment in sg_io()
  scsi: bsg: Drop needless assignment in scsi_bsg_sg_io_fn()
  scsi: lpfc: Copyright updates for 14.2.0.0 patches
  scsi: lpfc: Update lpfc version to 14.2.0.0
  scsi: lpfc: SLI path split: Refactor BSG paths
  scsi: lpfc: SLI path split: Refactor Abort paths
  scsi: lpfc: SLI path split: Refactor SCSI paths
  scsi: lpfc: SLI path split: Refactor CT paths
  scsi: lpfc: SLI path split: Refactor misc ELS paths
  scsi: lpfc: SLI path split: Refactor VMID paths
  scsi: lpfc: SLI path split: Refactor FDISC paths
  scsi: lpfc: SLI path split: Refactor LS_RJT paths
  scsi: lpfc: SLI path split: Refactor LS_ACC paths
  scsi: lpfc: SLI path split: Refactor the RSCN/SCR/RDF/EDC/FARPR paths
  scsi: lpfc: SLI path split: Refactor PLOGI/PRLI/ADISC/LOGO paths
  scsi: lpfc: SLI path split: Refactor base ELS paths and the FLOGI path
  scsi: lpfc: SLI path split: Introduce lpfc_prep_wqe
  scsi: lpfc: SLI path split: Refactor fast and slow paths to native SLI4
  scsi: lpfc: SLI path split: Refactor lpfc_iocbq
  scsi: lpfc: Use kcalloc()
  ...
2022-03-24 19:37:53 -07:00
Linus Torvalds
b1f8ccdaae - Significant refactoring and fixing of how DM core does bio-based IO
accounting with focus on fixing wildly inaccurate IO stats for
   dm-crypt (and other DM targets that defer bio submission in their
   own workqueues). End result is proper IO accounting, made possible
   by targets being updated to use the new dm_submit_bio_remap()
   interface.
 
 - Add hipri bio polling support (REQ_POLLED) to bio-based DM.
 
 - Reduce dm_io and dm_target_io structs so that a single dm_io (which
   contains dm_target_io and first clone bio) weighs in at 256 bytes.
   For reference the bio struct is 128 bytes.
 
 - Various other small cleanups, fixes or improvements in DM core and
   targets.
 
 - Update MAINTAINERS with my kernel.org email address to allow
   distinction between my "upstream" and "Red" Hats.
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Merge tag 'for-5.18/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Significant refactoring and fixing of how DM core does bio-based IO
   accounting with focus on fixing wildly inaccurate IO stats for
   dm-crypt (and other DM targets that defer bio submission in their own
   workqueues). End result is proper IO accounting, made possible by
   targets being updated to use the new dm_submit_bio_remap() interface.

 - Add hipri bio polling support (REQ_POLLED) to bio-based DM.

 - Reduce dm_io and dm_target_io structs so that a single dm_io (which
   contains dm_target_io and first clone bio) weighs in at 256 bytes.
   For reference the bio struct is 128 bytes.

 - Various other small cleanups, fixes or improvements in DM core and
   targets.

 - Update MAINTAINERS with my kernel.org email address to allow
   distinction between my "upstream" and "Red" Hats.

* tag 'for-5.18/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (46 commits)
  dm: consolidate spinlocks in dm_io struct
  dm: reduce size of dm_io and dm_target_io structs
  dm: switch dm_target_io booleans over to proper flags
  dm: switch dm_io booleans over to proper flags
  dm: update email address in MAINTAINERS
  dm: return void from __send_empty_flush
  dm: factor out dm_io_complete
  dm cache: use dm_submit_bio_remap
  dm: simplify dm_sumbit_bio_remap interface
  dm thin: use dm_submit_bio_remap
  dm: add WARN_ON_ONCE to dm_submit_bio_remap
  dm: support bio polling
  block: add ->poll_bio to block_device_operations
  dm mpath: use DMINFO instead of printk with KERN_INFO
  dm: stop using bdevname
  dm-zoned: remove the ->name field in struct dmz_dev
  dm: remove unnecessary local variables in __bind
  dm: requeue IO if mapping table not yet available
  dm io: remove stale comment block for dm_io()
  dm thin metadata: remove unused dm_thin_remove_block and __remove
  ...
2022-03-24 19:25:24 -07:00
Linus Torvalds
616355cc81 for-5.18/block-2022-03-18
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Merge tag 'for-5.18/block-2022-03-18' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - BFQ cleanups and fixes (Yu, Zhang, Yahu, Paolo)

 - blk-rq-qos completion fix (Tejun)

 - blk-cgroup merge fix (Tejun)

 - Add offline error return value to distinguish it from an IO error on
   the device (Song)

 - IO stats fixes (Zhang, Christoph)

 - blkcg refcount fixes (Ming, Yu)

 - Fix for indefinite dispatch loop softlockup (Shin'ichiro)

 - blk-mq hardware queue management improvements (Ming)

 - sbitmap dead code removal (Ming, John)

 - Plugging merge improvements (me)

 - Show blk-crypto capabilities in sysfs (Eric)

 - Multiple delayed queue run improvement (David)

 - Block throttling fixes (Ming)

 - Start deprecating auto module loading based on dev_t (Christoph)

 - bio allocation improvements (Christoph, Chaitanya)

 - Get rid of bio_devname (Christoph)

 - bio clone improvements (Christoph)

 - Block plugging improvements (Christoph)

 - Get rid of genhd.h header (Christoph)

 - Ensure drivers use appropriate flush helpers (Christoph)

 - Refcounting improvements (Christoph)

 - Queue initialization and teardown improvements (Ming, Christoph)

 - Misc fixes/improvements (Barry, Chaitanya, Colin, Dan, Jiapeng,
   Lukas, Nian, Yang, Eric, Chengming)

* tag 'for-5.18/block-2022-03-18' of git://git.kernel.dk/linux-block: (127 commits)
  block: cancel all throttled bios in del_gendisk()
  block: let blkcg_gq grab request queue's refcnt
  block: avoid use-after-free on throttle data
  block: limit request dispatch loop duration
  block/bfq-iosched: Fix spelling mistake "tenative" -> "tentative"
  sr: simplify the local variable initialization in sr_block_open()
  block: don't merge across cgroup boundaries if blkcg is enabled
  block: fix rq-qos breakage from skipping rq_qos_done_bio()
  block: flush plug based on hardware and software queue order
  block: ensure plug merging checks the correct queue at least once
  block: move rq_qos_exit() into disk_release()
  block: do more work in elevator_exit
  block: move blk_exit_queue into disk_release
  block: move q_usage_counter release into blk_queue_release
  block: don't remove hctx debugfs dir from blk_mq_exit_queue
  block: move blkcg initialization/destroy into disk allocation/release handler
  sr: implement ->free_disk to simplify refcounting
  sd: implement ->free_disk to simplify refcounting
  sd: delay calling free_opal_dev
  sd: call sd_zbc_release_disk before releasing the scsi_device reference
  ...
2022-03-21 16:48:55 -07:00
Mike Snitzer
4d7bca13dd dm: consolidate spinlocks in dm_io struct
No reason to have separate startio_lock and endio_lock given endio_lock
could be used during submission anyway.

This change leaves the dm_io struct weighing in at 256 bytes (down
from 272 bytes, so saves a cacheline).

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-03-21 14:15:36 -04:00
Mike Snitzer
655f3aad7a dm: switch dm_target_io booleans over to proper flags
Add flags to dm_target_io and manage them using the same pattern used
for bi_flags in struct bio.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-03-21 14:15:35 -04:00