Commit Graph

433 Commits

Author SHA1 Message Date
NeilBrown f5fe1b5190 blk: Ensure users for current->bio_list can see the full list.
Commit 79bd99596b ("blk: improve order of bio handling in generic_make_request()")
changed current->bio_list so that it did not contain *all* of the
queued bios, but only those submitted by the currently running
make_request_fn.

There are two places which walk the list and requeue selected bios,
and others that check if the list is empty.  These are no longer
correct.

So redefine current->bio_list to point to an array of two lists, which
contain all queued bios, and adjust various code to test or walk both
lists.

Signed-off-by: NeilBrown <neilb@suse.com>
Fixes: 79bd99596b ("blk: improve order of bio handling in generic_make_request()")
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-11 15:31:37 -07:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Linus Torvalds 7a771ceac7 - Fix dm-raid transient device failure processing and other smaller
tweaks.
 
 - Add journal support to the DM raid target to close the 'write hole' on
   raid 4/5/6.
 
 - Fix dm-cache corruption, due to rounding bug, when cache exceeds 2TB.
 
 - Add 'metadata2' feature to dm-cache to separate the dirty bitset out
   from other cache metadata.  This improves speed of shutting down
   a large cache device (which implies writing out dirty bits).
 
 - Fix a memory leak during dm-stats data structure destruction.
 
 - Fix a DM multipath round-robin path selector performance regression
   that was caused by less precise balancing across all paths.
 
 - Lastly, introduce a DM core fix for a long-standing DM snapshot
   deadlock that is rooted in the complexity of the device stack used in
   conjunction with block core maintaining bios on current->bio_list to
   manage recursion in generic_make_request().  A more comprehensive fix
   to block core (and its hook in the cpu scheduler) would be wonderful
   but this DM-specific fix is pragmatic considering how difficult it has
   been to make progress on a generic fix.
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Merge tag 'dm-4.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Fix dm-raid transient device failure processing and other smaller
   tweaks.

 - Add journal support to the DM raid target to close the 'write hole'
   on raid 4/5/6.

 - Fix dm-cache corruption, due to rounding bug, when cache exceeds 2TB.

 - Add 'metadata2' feature to dm-cache to separate the dirty bitset out
   from other cache metadata. This improves speed of shutting down a
   large cache device (which implies writing out dirty bits).

 - Fix a memory leak during dm-stats data structure destruction.

 - Fix a DM multipath round-robin path selector performance regression
   that was caused by less precise balancing across all paths.

 - Lastly, introduce a DM core fix for a long-standing DM snapshot
   deadlock that is rooted in the complexity of the device stack used in
   conjunction with block core maintaining bios on current->bio_list to
   manage recursion in generic_make_request(). A more comprehensive fix
   to block core (and its hook in the cpu scheduler) would be wonderful
   but this DM-specific fix is pragmatic considering how difficult it
   has been to make progress on a generic fix.

* tag 'dm-4.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (22 commits)
  dm: flush queued bios when process blocks to avoid deadlock
  dm round robin: revert "use percpu 'repeat_count' and 'current_path'"
  dm stats: fix a leaked s->histogram_boundaries array
  dm space map metadata: constify dm_space_map structures
  dm cache metadata: use cursor api in blocks_are_clean_separate_dirty()
  dm persistent data: add cursor skip functions to the cursor APIs
  dm cache metadata: use dm_bitset_new() to create the dirty bitset in format 2
  dm bitset: add dm_bitset_new()
  dm cache metadata: name the cache block that couldn't be loaded
  dm cache metadata: add "metadata2" feature
  dm cache metadata: use bitset cursor api to load discard bitset
  dm bitset: introduce cursor api
  dm btree: use GFP_NOFS in dm_btree_del()
  dm space map common: memcpy the disk root to ensure it's arch aligned
  dm block manager: add unlikely() annotations on dm_bufio error paths
  dm cache: fix corruption seen when using cache > 2TB
  dm raid: cleanup awkward branching in raid_message() option processing
  dm raid: use mddev rather than rdev->mddev
  dm raid: use read_disk_sb() throughout
  dm raid: add raid4/5/6 journaling support
  ...
2017-02-21 12:11:41 -08:00
Mikulas Patocka d67a5f4b59 dm: flush queued bios when process blocks to avoid deadlock
Commit df2cb6daa4 ("block: Avoid deadlocks with bio allocation by
stacking drivers") created a workqueue for every bio set and code
in bio_alloc_bioset() that tries to resolve some low-memory deadlocks
by redirecting bios queued on current->bio_list to the workqueue if the
system is low on memory.  However other deadlocks (see below **) may
happen, without any low memory condition, because generic_make_request
is queuing bios to current->bio_list (rather than submitting them).

** the related dm-snapshot deadlock is detailed here:
https://www.redhat.com/archives/dm-devel/2016-July/msg00065.html

Fix this deadlock by redirecting any bios on current->bio_list to the
bio_set's rescue workqueue on every schedule() call.  Consequently,
when the process blocks on a mutex, the bios queued on
current->bio_list are dispatched to independent workqueus and they can
complete without waiting for the mutex to be available.

The structure blk_plug contains an entry cb_list and this list can contain
arbitrary callback functions that are called when the process blocks.
To implement this fix DM (ab)uses the onstack plug's cb_list interface
to get its flush_current_bio_list() called at schedule() time.

This fixes the snapshot deadlock - if the map method blocks,
flush_current_bio_list() will be called and it redirects bios waiting
on current->bio_list to appropriate workqueues.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1267650
Depends-on: df2cb6daa4 ("block: Avoid deadlocks with bio allocation by stacking drivers")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-02-17 00:54:10 -05:00
Christoph Hellwig e980f62353 dm: don't allow ioctls to targets that don't map to whole devices
.. at least for unprivileged users.  Before we called into the SCSI
ioctl code to allow excemptions for a few SCSI passthrough ioctls,
but this is pretty unsafe and except for this call dm knows nothing
about SCSI ioctls.

As the SCSI ioctl code is now optional, we really don't want to
drag it in for DM, and the exception is not very useful anyway.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-04 10:19:40 -07:00
Jan Kara dc3b17cc8b block: Use pointer to backing_dev_info from request_queue
We will want to have struct backing_dev_info allocated separately from
struct request_queue. As the first step add pointer to backing_dev_info
to request_queue and convert all users touching it. No functional
changes in this patch.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-02 08:20:48 -07:00
Christoph Hellwig eb8db831be dm: always defer request allocation to the owner of the request_queue
DM already calls blk_mq_alloc_request on the request_queue of the
underlying device if it is a blk-mq device.  But now that we allow drivers
to allocate additional data and initialize it ahead of time we need to do
the same for all drivers.   Doing so and using the new cmd_size
infrastructure in the block layer greatly simplifies the dm-rq and mpath
code, and should also make arbitrary combinations of SQ and MQ devices
with SQ or MQ device mapper tables easily possible as a further step.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-27 15:08:35 -07:00
Linus Torvalds 775a2e29c3 . various fixes and improvements to request-based DM and DM multipath
. some locking improvements in DM bufio
 
 . add Kconfig option to disable the DM block manager's extra locking
   which mainly serves as a developer tool
 
 . a few bug fixes to DM's persistent-data
 
 . a couple changes to prepare for multipage biovec support in the block
   layer
 
 . various improvements and cleanups in the DM core, DM cache, DM raid
   and DM crypt
 
 . add ability to have DM crypt use keys from the kernel key retention
   service
 
 . add a new "error_writes" feature to the DM flakey target, reads are
   left unchanged in this mode
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Merge tag 'dm-4.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - various fixes and improvements to request-based DM and DM multipath

 - some locking improvements in DM bufio

 - add Kconfig option to disable the DM block manager's extra locking
   which mainly serves as a developer tool

 - a few bug fixes to DM's persistent-data

 - a couple changes to prepare for multipage biovec support in the block
   layer

 - various improvements and cleanups in the DM core, DM cache, DM raid
   and DM crypt

 - add ability to have DM crypt use keys from the kernel key retention
   service

 - add a new "error_writes" feature to the DM flakey target, reads are
   left unchanged in this mode

* tag 'dm-4.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (40 commits)
  dm flakey: introduce "error_writes" feature
  dm cache policy smq: use hash_32() instead of hash_32_generic()
  dm crypt: reject key strings containing whitespace chars
  dm space map: always set ev if sm_ll_mutate() succeeds
  dm space map metadata: skip useless memcpy in metadata_ll_init_index()
  dm space map metadata: fix 'struct sm_metadata' leak on failed create
  Documentation: dm raid: define data_offset status field
  dm raid: fix discard support regression
  dm raid: don't allow "write behind" with raid4/5/6
  dm mpath: use hw_handler_params if attached hw_handler is same as requested
  dm crypt: add ability to use keys from the kernel key retention service
  dm array: remove a dead assignment in populate_ablock_with_values()
  dm ioctl: use offsetof() instead of open-coding it
  dm rq: simplify use_blk_mq initialization
  dm: use blk_set_queue_dying() in __dm_destroy()
  dm bufio: drop the lock when doing GFP_NOIO allocation
  dm bufio: don't take the lock in dm_bufio_shrink_count
  dm bufio: avoid sleeping while holding the dm_bufio lock
  dm table: simplify dm_table_determine_type()
  dm table: an 'all_blk_mq' table must be loaded for a blk-mq DM device
  ...
2016-12-14 11:01:00 -08:00
Linus Torvalds 36869cb93d Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
 "This is the main block pull request this series. Contrary to previous
  release, I've kept the core and driver changes in the same branch. We
  always ended up having dependencies between the two for obvious
  reasons, so makes more sense to keep them together. That said, I'll
  probably try and keep more topical branches going forward, especially
  for cycles that end up being as busy as this one.

  The major parts of this pull request is:

   - Improved support for O_DIRECT on block devices, with a small
     private implementation instead of using the pig that is
     fs/direct-io.c. From Christoph.

   - Request completion tracking in a scalable fashion. This is utilized
     by two components in this pull, the new hybrid polling and the
     writeback queue throttling code.

   - Improved support for polling with O_DIRECT, adding a hybrid mode
     that combines pure polling with an initial sleep. From me.

   - Support for automatic throttling of writeback queues on the block
     side. This uses feedback from the device completion latencies to
     scale the queue on the block side up or down. From me.

   - Support from SMR drives in the block layer and for SD. From Hannes
     and Shaun.

   - Multi-connection support for nbd. From Josef.

   - Cleanup of request and bio flags, so we have a clear split between
     which are bio (or rq) private, and which ones are shared. From
     Christoph.

   - A set of patches from Bart, that improve how we handle queue
     stopping and starting in blk-mq.

   - Support for WRITE_ZEROES from Chaitanya.

   - Lightnvm updates from Javier/Matias.

   - Supoort for FC for the nvme-over-fabrics code. From James Smart.

   - A bunch of fixes from a whole slew of people, too many to name
     here"

* 'for-4.10/block' of git://git.kernel.dk/linux-block: (182 commits)
  blk-stat: fix a few cases of missing batch flushing
  blk-flush: run the queue when inserting blk-mq flush
  elevator: make the rqhash helpers exported
  blk-mq: abstract out blk_mq_dispatch_rq_list() helper
  blk-mq: add blk_mq_start_stopped_hw_queue()
  block: improve handling of the magic discard payload
  blk-wbt: don't throttle discard or write zeroes
  nbd: use dev_err_ratelimited in io path
  nbd: reset the setup task for NBD_CLEAR_SOCK
  nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME
  nvme-fabrics: Add target support for FC transport
  nvme-fabrics: Add host support for FC transport
  nvme-fabrics: Add FC transport LLDD api definitions
  nvme-fabrics: Add FC transport FC-NVME definitions
  nvme-fabrics: Add FC transport error codes to nvme.h
  Add type 0x28 NVME type code to scsi fc headers
  nvme-fabrics: patch target code in prep for FC transport support
  nvme-fabrics: set sqe.command_id in core not transports
  parser: add u64 number parser
  nvme-rdma: align to generic ib_event logging helper
  ...
2016-12-13 10:19:16 -08:00
Bart Van Assche 2e91c36941 dm: use blk_set_queue_dying() in __dm_destroy()
After QUEUE_FLAG_DYING has been set any code that is waiting in
get_request() should be woken up.  But to get this behaviour
blk_set_queue_dying() must be used instead of only setting
QUEUE_FLAG_DYING.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-12-08 14:13:06 -05:00
Ming Lei 3a83f46775 block: bio: pass bvec table to bio_init()
Some drivers often use external bvec table, so introduce
this helper for this case. It is always safe to access the
bio->bi_io_vec in this way for this case.

After converting to this usage, it will becomes a bit easier
to evaluate the remaining direct access to bio->bi_io_vec,
so it can help to prepare for the following multipage bvec
support.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Fixed up the new O_DIRECT cases.

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-22 08:57:21 -07:00
Christoph Hellwig 70fd76140a block,fs: use REQ_* flags directly
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags
directly.  Where applicable this also drops usage of the
bio_set_op_attrs wrapper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-01 09:43:26 -06:00
Linus Torvalds e0f3e6a7cc - A couple DM raid and DM mirror fixes
- A couple .request_fn request-based DM NULL pointer fixes
 
 - A fix for a DM target reference count leak, on target load error, that
   prevented associated DM target kernel module(s) from being removed
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Merge tag 'dm-4.9-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - a couple DM raid and DM mirror fixes

 - a couple .request_fn request-based DM NULL pointer fixes

 - a fix for a DM target reference count leak, on target load error,
   that prevented associated DM target kernel module(s) from being
   removed

* tag 'dm-4.9-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm table: fix missing dm_put_target_type() in dm_table_add_target()
  dm rq: clear kworker_task if kthread_run() returned an error
  dm: free io_barrier after blk_cleanup_queue call
  dm raid: fix activation of existing raid4/10 devices
  dm mirror: use all available legs on multiple failures
  dm mirror: fix read error on recovery after default leg failure
  dm raid: fix compat_features validation
2016-10-28 09:27:58 -07:00
Tahsin Erdogan d09960b003 dm: free io_barrier after blk_cleanup_queue call
dm_old_request_fn() has paths that access md->io_barrier.  The party
destroying io_barrier should ensure that no future execution of
dm_old_request_fn() is possible.  Move io_barrier destruction to below
blk_cleanup_queue() to ensure this and avoid a NULL pointer crash during
request-based DM device shutdown.

Cc: stable@vger.kernel.org # 4.3+
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-10-18 12:02:08 -04:00
Petr Mladek 3989144f86 kthread: kthread worker API cleanup
A good practice is to prefix the names of functions by the name
of the subsystem.

The kthread worker API is a mix of classic kthreads and workqueues.  Each
worker has a dedicated kthread.  It runs a generic function that process
queued works.  It is implemented as part of the kthread subsystem.

This patch renames the existing kthread worker API to use
the corresponding name from the workqueues API prefixed by
kthread_:

__init_kthread_worker()		-> __kthread_init_worker()
init_kthread_worker()		-> kthread_init_worker()
init_kthread_work()		-> kthread_init_work()
insert_kthread_work()		-> kthread_insert_work()
queue_kthread_work()		-> kthread_queue_work()
flush_kthread_work()		-> kthread_flush_work()
flush_kthread_worker()		-> kthread_flush_worker()

Note that the names of DEFINE_KTHREAD_WORK*() macros stay
as they are. It is common that the "DEFINE_" prefix has
precedence over the subsystem names.

Note that INIT() macros and init() functions use different
naming scheme. There is no good solution. There are several
reasons for this solution:

  + "init" in the function names stands for the verb "initialize"
    aka "initialize worker". While "INIT" in the macro names
    stands for the noun "INITIALIZER" aka "worker initializer".

  + INIT() macros are used only in DEFINE() macros

  + init() functions are used close to the other kthread()
    functions. It looks much better if all the functions
    use the same scheme.

  + There will be also kthread_destroy_worker() that will
    be used close to kthread_cancel_work(). It is related
    to the init() function. Again it looks better if all
    functions use the same naming scheme.

  + there are several precedents for such init() function
    names, e.g. amd_iommu_init_device(), free_area_init_node(),
    jump_label_init_type(),  regmap_init_mmio_clk(),

  + It is not an argument but it was inconsistent even before.

[arnd@arndb.de: fix linux-next merge conflict]
 Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11 15:06:33 -07:00
Bart Van Assche 9f4c3f874a dm: convert wait loops to use autoremove_wake_function()
Use autoremove_wake_function() instead of default_wake_function()
to make the dm wait loops more similar to other wait loops in the
kernel.  This patch does not change any functionality.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-14 13:56:38 -04:00
Bart Van Assche e3fabdfdf7 dm: use signal_pending_state() in dm_wait_for_completion()
Use signal_pending_state() instead of open-coding it.  This patch does
not change any functionality but makes it possible to pass TASK_KILLABLE
as the second argument of dm_wait_for_completion().  See also commit
16882c1e96 ("sched: fix TASK_WAKEKILL vs SIGKILL race").

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-14 13:56:38 -04:00
Bart Van Assche b48633f83f dm: rename task state function arguments
Rename 'interruptible' into 'task_state' to make it clear that this
argument is a task state instead of a boolean.  Also, change type from
int to long.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-14 13:56:38 -04:00
Bart Van Assche 5a8f1f80e9 dm: add two lockdep_assert_held() statements
Document the locking assumptions for the __bind() and __dm_suspend()
functions.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-14 13:56:38 -04:00
Bart Van Assche 3b785fbcf8 dm: mark request_queue dead before destroying the DM device
This avoids that new requests are queued while __dm_destroy() is in
progress.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2016-09-14 13:56:38 -04:00
Minfei Huang 8dc23658b7 dm: return correct error code in dm_resume()'s retry loop
dm_resume() will return success (0) rather than -EINVAL if
!dm_suspended_md() upon retry within dm_resume().

Reset the error code at the start of dm_resume()'s retry loop.
Also, remove a useless assignment at the end of dm_resume().

Fixes: ffcc393641 ("dm: enhance internal suspend and resume interface")
Cc: stable@vger.kernel.org # 3.19+
Signed-off-by: Minfei Huang <mnghuan@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-14 13:56:38 -04:00
Jens Axboe 1eff9d322a block: rename bio bi_rw to bi_opf
Since commit 63a4cc2486, 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: Jens Axboe <axboe@fb.com>
2016-08-07 14:41:02 -06:00
Mike Snitzer eaf9a7361f dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING
Otherwise, there is potential for both DMF_SUSPENDED* and
DMF_NOFLUSH_SUSPENDING to not be set during dm_suspend() -- which is
definitely _not_ a valid state.

This fix, in conjuction with "dm rq: fix the starting and stopping of
blk-mq queues", addresses the potential for request-based DM multipath's
__multipath_map() to see !dm_noflush_suspending() during suspend.

Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2016-08-02 16:21:37 -04:00
Linus Torvalds f0c98ebc57 libnvdimm for 4.8
1/ Replace pcommit with ADR / directed-flushing:
    The pcommit instruction, which has not shipped on any product, is
    deprecated. Instead, the requirement is that platforms implement either
    ADR, or provide one or more flush addresses per nvdimm. ADR
    (Asynchronous DRAM Refresh) flushes data in posted write buffers to the
    memory controller on a power-fail event. Flush addresses are defined in
    ACPI 6.x as an NVDIMM Firmware Interface Table (NFIT) sub-structure:
    "Flush Hint Address Structure". A flush hint is an mmio address that
    when written and fenced assures that all previous posted writes
    targeting a given dimm have been flushed to media.
 
 2/ On-demand ARS (address range scrub):
    Linux uses the results of the ACPI ARS commands to track bad blocks
    in pmem devices.  When latent errors are detected we re-scrub the media
    to refresh the bad block list, userspace can also request a re-scrub at
    any time.
 
 3/ Support for the Microsoft DSM (device specific method) command format.
 
 4/ Support for EDK2/OVMF virtual disk device memory ranges.
 
 5/ Various fixes and cleanups across the subsystem.
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Merge tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:

 - Replace pcommit with ADR / directed-flushing.

   The pcommit instruction, which has not shipped on any product, is
   deprecated.  Instead, the requirement is that platforms implement
   either ADR, or provide one or more flush addresses per nvdimm.

   ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers
   to the memory controller on a power-fail event.

   Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware
   Interface Table (NFIT) sub-structure: "Flush Hint Address Structure".
   A flush hint is an mmio address that when written and fenced assures
   that all previous posted writes targeting a given dimm have been
   flushed to media.

 - On-demand ARS (address range scrub).

   Linux uses the results of the ACPI ARS commands to track bad blocks
   in pmem devices.  When latent errors are detected we re-scrub the
   media to refresh the bad block list, userspace can also request a
   re-scrub at any time.

 - Support for the Microsoft DSM (device specific method) command
   format.

 - Support for EDK2/OVMF virtual disk device memory ranges.

 - Various fixes and cleanups across the subsystem.

* tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits)
  libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
  nfit: do an ARS scrub on hitting a latent media error
  nfit: move to nfit/ sub-directory
  nfit, libnvdimm: allow an ARS scrub to be triggered on demand
  libnvdimm: register nvdimm_bus devices with an nd_bus driver
  pmem: clarify a debug print in pmem_clear_poison
  x86/insn: remove pcommit
  Revert "KVM: x86: add pcommit support"
  nfit, tools/testing/nvdimm/: unify shutdown paths
  libnvdimm: move ->module to struct nvdimm_bus_descriptor
  nfit: cleanup acpi_nfit_init calling convention
  nfit: fix _FIT evaluation memory leak + use after free
  tools/testing/nvdimm: add manufacturing_{date|location} dimm properties
  tools/testing/nvdimm: add virtual ramdisk range
  acpi, nfit: treat virtual ramdisk SPA as pmem region
  pmem: kill __pmem address space
  pmem: kill wmb_pmem()
  libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes
  fs/dax: remove wmb_pmem()
  libnvdimm, pmem: flush posted-write queues on shutdown
  ...
2016-07-28 17:38:16 -07:00
Linus Torvalds f7e6816994 - initially based on Jens' 'for-4.8/core' (given all the flag churn) and
later merged with 'for-4.8/core' to pickup the QUEUE_FLAG_DAX commits
   that DM depends on to provide its DAX support
 
 - clean up the bio-based vs request-based DM core code by moving the
   request-based DM core code out to dm-rq.[hc]
 
 - reinstate bio-based support in the DM multipath target (done with the
   idea that fast storage like NVMe over Fabrics could benefit) -- while
   preserving support for request_fn and blk-mq request-based DM mpath
 
 - SCSI and DM multipath persistent reservation fixes that were
   coordinated with Martin Petersen.
 
 - the DM raid target saw the most extensive change this cycle; it now
   provides reshape and takeover support (by layering ontop of the
   corresponding MD capabilities)
 
 - DAX support for DM core and the linear, stripe and error targets
 
 - A DM thin-provisioning block discard vs allocation race fix that
   addresses potential for corruption
 
 - A stable fix for DM verity-fec's block calculation during decode
 
 - A few cleanups and fixes to DM core and various targets
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Merge tag 'dm-4.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - initially based on Jens' 'for-4.8/core' (given all the flag churn)
   and later merged with 'for-4.8/core' to pickup the QUEUE_FLAG_DAX
   commits that DM depends on to provide its DAX support

 - clean up the bio-based vs request-based DM core code by moving the
   request-based DM core code out to dm-rq.[hc]

 - reinstate bio-based support in the DM multipath target (done with the
   idea that fast storage like NVMe over Fabrics could benefit) -- while
   preserving support for request_fn and blk-mq request-based DM mpath

 - SCSI and DM multipath persistent reservation fixes that were
   coordinated with Martin Petersen.

 - the DM raid target saw the most extensive change this cycle; it now
   provides reshape and takeover support (by layering ontop of the
   corresponding MD capabilities)

 - DAX support for DM core and the linear, stripe and error targets

 - a DM thin-provisioning block discard vs allocation race fix that
   addresses potential for corruption

 - a stable fix for DM verity-fec's block calculation during decode

 - a few cleanups and fixes to DM core and various targets

* tag 'dm-4.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (73 commits)
  dm: allow bio-based table to be upgraded to bio-based with DAX support
  dm snap: add fake origin_direct_access
  dm stripe: add DAX support
  dm error: add DAX support
  dm linear: add DAX support
  dm: add infrastructure for DAX support
  dm thin: fix a race condition between discarding and provisioning a block
  dm btree: fix a bug in dm_btree_find_next_single()
  dm raid: fix random optimal_io_size for raid0
  dm raid: address checkpatch.pl complaints
  dm: call PR reserve/unreserve on each underlying device
  sd: don't use the ALL_TG_PT bit for reservations
  dm: fix second blk_delay_queue() parameter to be in msec units not jiffies
  dm raid: change logical functions to actually return bool
  dm raid: use rdev_for_each in status
  dm raid: use rs->raid_disks to avoid memory leaks on free
  dm raid: support delta_disks for raid1, fix table output
  dm raid: enhance reshape check and factor out reshape setup
  dm raid: allow resize during recovery
  dm raid: fix rs_is_recovering() to allow for lvextend
  ...
2016-07-26 17:12:11 -07:00
Toshi Kani 545ed20e6d dm: add infrastructure for DAX support
Change mapped device to implement direct_access function,
dm_blk_direct_access(), which calls a target direct_access function.
'struct target_type' is extended to have target direct_access interface.
This function limits direct accessible size to the dm_target's limit
with max_io_len().

Add dm_table_supports_dax() to iterate all targets and associated block
devices to check for DAX support.  To add DAX support to a DM target the
target must only implement the direct_access function.

Add a new dm type, DM_TYPE_DAX_BIO_BASED, which indicates that mapped
device supports DAX and is bio based.  This new type is used to assure
that all target devices have DAX support and remain that way after
QUEUE_FLAG_DAX is set in mapped device.

At initial table load, QUEUE_FLAG_DAX is set to mapped device when setting
DM_TYPE_DAX_BIO_BASED to the type.  Any subsequent table load to the
mapped device must have the same type, or else it fails per the check in
table_load().

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-07-20 23:49:49 -04:00
Christoph Hellwig 70246286e9 block: get rid of bio_rw and READA
These two are confusing leftover of the old world order, combining
values of the REQ_OP_ and REQ_ namespaces.  For callers that don't
special case we mostly just replace bi_rw with bio_data_dir or
op_is_write, except for the few cases where a switch over the REQ_OP_
values makes more sense.  Any check for READA is replaced with an
explicit check for REQ_RAHEAD.  Also remove the READA alias for
REQ_RAHEAD.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-07-20 17:37:01 -06:00
Christoph Hellwig 9c72bad1f3 dm: call PR reserve/unreserve on each underlying device
So far we tried to rely on the SCSI 'all target ports' bit to register
all path, but for many setups this didn't work properly as the different
paths are seen as separate initiators to the target instead of multiple
ports of the same initiator.  Because of that we'll stop setting the
'all target ports' bit in SCSI, and let device mapper handle iterating
over the device for each path and register them manually.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-07-18 15:37:35 -04:00
Mike Snitzer e83068a5fa dm mpath: add optional "queue_mode" feature
Allow a user to specify an optional feature 'queue_mode <mode>' where
<mode> may be "bio", "rq" or "mq" -- which corresponds to bio-based,
request_fn rq-based, and blk-mq rq-based respectively.

If the queue_mode feature isn't specified the default for the
"multipath" target is still "rq" but if dm_mod.use_blk_mq is set to Y
it'll default to mode "mq".

This new queue_mode feature introduces the ability for each multipath
device to have its own queue_mode (whereas before this feature all
multipath devices effectively had to have the same queue_mode).

This commit also goes a long way to eliminate the awkward (ab)use of
DM_TYPE_*, the associated filter_md_type() and other relatively fragile
and difficult to maintain code.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-06-10 15:16:02 -04:00
Mike Snitzer 4cc96131af dm: move request-based code out to dm-rq.[hc]
Add some seperation between bio-based and request-based DM core code.

'struct mapped_device' and other DM core only structures and functions
have been moved to dm-core.h and all relevant DM core .c files have been
updated to include dm-core.h rather than dm.h

DM targets should _never_ include dm-core.h!

[block core merge conflict resolution from Stephen Rothwell]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
2016-06-10 15:15:44 -04:00
Mike Christie 28a8f0d317 block, drivers, fs: rename REQ_FLUSH to REQ_PREFLUSH
To avoid confusion between REQ_OP_FLUSH, which is handled by
request_fn drivers, and upper layers requesting the block layer
perform a flush sequence along with possibly a WRITE, this patch
renames REQ_FLUSH to REQ_PREFLUSH.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07 13:41:38 -06:00
Mike Christie 3a5e02ced1 block, drivers: add REQ_OP_FLUSH operation
This adds a REQ_OP_FLUSH operation that is sent to request_fn
based drivers by the block layer's flush code, instead of
sending requests with the request->cmd_flags REQ_FLUSH bit set.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07 13:41:38 -06:00
Mike Christie c2df40dfb8 drivers: use req op accessor
The req operation REQ_OP is separated from the rq_flag_bits
definition. This converts the block layer drivers to
use req_op to get the op from the request struct.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07 13:41:38 -06:00
Mike Christie e6047149db dm: use bio op accessors
Separate the op from the rq_flag_bits and have dm
set/get the bio using bio_set_op_attrs/bio_op.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07 13:41:38 -06:00
Mike Christie 528ec5abe6 dm: pass dm stats data dir instead of bi_rw
It looks like dm stats cares about the data direction
(READ vs WRITE) and does not need the bio/request flags.
Commands like REQ_FLUSH, REQ_DISCARD and REQ_WRITE_SAME
are currently always set with REQ_WRITE, so the extra check for
REQ_DISCARD in dm_stats_account_io is not needed.

This patch has it use the bio and request data_dir helpers
instead of accessing the bi_rw/cmd_flags directly. This makes
the next patches that remove the operation from the cmd_flags
and bi_rw easier, because we will no longer have the REQ_WRITE
bit set for operations like discards.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07 13:41:38 -06:00
Mike Snitzer cfae7529b5 dm: remove unused mapped_device argument from free_tio()
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-05-05 15:25:49 -04:00
Mikulas Patocka 072623de1f dm: fix dm_target_io leak if clone_bio() returns an error
Commit c80914e81e ("dm: return error if bio_integrity_clone() fails
in clone_bio()") changed clone_bio() such that if it does return error
then the alloc_tio() created resources (both the bio that was allocated
to be a clone and the containing dm_target_io struct) will leak.

Fix this by calling free_tio() in __clone_and_map_data_bio()'s
clone_bio() error path.

Fixes: c80914e81e ("dm: return error if bio_integrity_clone() fails in clone_bio()")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-04-11 11:49:09 -04:00
Bryn M. Reeves 98dbc9c6c6 dm: fix rq_end_stats() NULL pointer in dm_requeue_original_request()
An "old" (.request_fn) DM 'struct request' stores a pointer to the
associated 'struct dm_rq_target_io' in rq->special.

dm_requeue_original_request(), previously named
dm_requeue_unmapped_original_request(), called dm_unprep_request() to
reset rq->special to NULL.  But rq_end_stats() would go on to hit a NULL
pointer deference because its call to tio_from_request() returned NULL.

Fix this by calling rq_end_stats() _before_ dm_unprep_request()

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fixes: e262f34741 ("dm stats: add support for request-based DM devices")
Cc: stable@vger.kernel.org # 4.2+
2016-03-14 17:04:34 -04:00
Mike Snitzer c80914e81e dm: return error if bio_integrity_clone() fails in clone_bio()
clone_bio() now checks if bio_integrity_clone() returned an error rather
than just drop it on the floor.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-03-10 17:12:10 -05:00
Bob Liu e233d800a9 dm: drop unnecessary assignment of md->queue
md->queue and q are the same thing in dm_old_init_request_queue() and
dm_mq_init_request_queue().

Also drop the temporary 'struct request_queue *q' in
dm_old_init_request_queue().

Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-03-10 17:12:07 -05:00
Mike Snitzer 032482fda4 dm: reorder 'struct mapped_device' members to fix alignment and holes
Saves 16 bytes by eliminating 4 4byte holes but more importantly:
numerous members that crossed cachelines were fixed.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-03-10 17:12:07 -05:00
Mike Snitzer 1d3aa6f683 dm: remove dummy definition of 'struct dm_table'
Change the map pointer in 'struct mapped_device' from 'struct dm_table
__rcu *' to 'void __rcu *' to avoid the need for the dummy definition.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-03-10 17:12:06 -05:00
Mike Snitzer 115485e83f dm: add 'dm_numa_node' module parameter
Allows user to control which NUMA node the memory for DM device
structures (e.g. mapped_device, request_queue, gendisk, blk_mq_tag_set)
is allocated from.

Defaults to NUMA_NO_NODE (-1).  Allowable range is from -1 until the
last online NUMA node id.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-03-10 17:12:06 -05:00
Mike Snitzer 591ddcfc4b dm: allow immutable request-based targets to use blk-mq pdu
This will allow DM multipath to use a portion of the blk-mq pdu space
for target data (e.g. struct dm_mpath_io).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-02-22 22:34:37 -05:00
Mike Snitzer 30187e1d48 dm: rename target's per_bio_data_size to per_io_data_size
Request-based DM will also make use of per_bio_data_size.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-02-22 22:34:37 -05:00
Mike Snitzer eca7ee6dc0 dm: distinquish old .request_fn (dm-old) vs dm-mq request-based DM
Rename various methods to have either a "dm_old" or "dm_mq" prefix.
Improve code comments to assist with understanding the duality of code
that handles both "dm_old" and "dm_mq" cases.

It is no much easier to quickly look at the code and _know_ that a given
method is either 1) "dm_old" only 2) "dm_mq" only 3) common to both.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-02-22 22:34:33 -05:00
Mike Snitzer c5248f79f3 dm: remove support for stacking dm-mq on .request_fn device(s)
Remove all fiddley code that propped up this support for a blk-mq
request-queue ontop of all .request_fn devices.

Testing has proven this niche request-based dm-mq mode to be buggy, when
testing fault tolerance with DM multipath, and there is no point trying
to preserve it.

Should help improve efficiency of pure dm-mq code and make code
maintenance less delicate.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-02-22 22:33:46 -05:00
Mike Snitzer 818c5f3bef dm: fix a couple locking issues with use of block interfaces
old_stop_queue() was checking blk_queue_stopped() without holding the
q->queue_lock.

dm_requeue_original_request() needed to check blk_queue_stopped(), with
q->queue_lock held, before calling blk_mq_kick_requeue_list().  And a
side-effect of that change is start_queue() must also call
blk_mq_kick_requeue_list().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-02-22 22:33:09 -05:00
Mike Snitzer 1c357a1e86 dm: allocate blk_mq_tag_set rather than embed in mapped_device
The blk_mq_tag_set is only needed for dm-mq support.  There is point
wasting space in 'struct mapped_device' for non-dm-mq devices.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> # check kzalloc return
2016-02-22 12:07:14 -05:00
Mike Snitzer faad87df4b dm: add 'dm_mq_nr_hw_queues' and 'dm_mq_queue_depth' module params
Allow user to change these values via module params or sysfs.

'dm_mq_nr_hw_queues' defaults to 1 (max 32).

'dm_mq_queue_depth' defaults to 2048 (up from 64, which proved far too
small under moderate sized workloads -- the dm-multipath device would
continuously block waiting for tags (requests) to become available).
The maximum is BLK_MQ_MAX_DEPTH (currently 10240).

Keep in mind the total number of pre-allocated requests per
request-based dm-mq device is 'dm_mq_nr_hw_queues' * 'dm_mq_queue_depth'
(currently 2048).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-02-22 12:07:10 -05:00