Pull MD updates from Shaohua Li:
- Add Partial Parity Log (ppl) feature found in Intel IMSM raid array
by Artur Paszkiewicz. This feature is another way to close RAID5
writehole. The Linux implementation is also available for normal
RAID5 array if specific superblock bit is set.
- A number of md-cluser fixes and enabling md-cluster array resize from
Guoqing Jiang
- A bunch of patches from Ming Lei and Neil Brown to rewrite MD bio
handling related code. Now MD doesn't directly access bio bvec,
bi_phys_segments and uses modern bio API for bio split.
- Improve RAID5 IO pattern to improve performance for hard disk based
RAID5/6 from me.
- Several patches from Song Liu to speed up raid5-cache recovery and
allow raid5 cache feature disabling in runtime.
- Fix a performance regression in raid1 resync from Xiao Ni.
- Other cleanup and fixes from various people.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: (84 commits)
md/raid10: skip spare disk as 'first' disk
md/raid1: Use a new variable to count flighting sync requests
md: clear WantReplacement once disk is removed
md/raid1/10: remove unused queue
md: handle read-only member devices better.
md/raid10: wait up frozen array in handle_write_completed
uapi: fix linux/raid/md_p.h userspace compilation error
md-cluster: Fix a memleak in an error handling path
md: support disabling of create-on-open semantics.
md: allow creation of mdNNN arrays via md_mod/parameters/new_array
raid5-ppl: use a single mempool for ppl_io_unit and header_page
md/raid0: fix up bio splitting.
md/linear: improve bio splitting.
md/raid5: make chunk_aligned_read() split bios more cleanly.
md/raid10: simplify handle_read_error()
md/raid10: simplify the splitting of requests.
md/raid1: factor out flush_bio_list()
md/raid1: simplify handle_read_error().
Revert "block: introduce bio_copy_data_partial"
md/raid1: simplify alloc_behind_master_bio()
...
Remove the request_idx parameter, which can't be used safely now that we
support I/O schedulers with blk-mq. Except for a superflous check in
mtip32xx it was unused anyway.
Also pass the tag_set instead of just the driver data - this allows drivers
to avoid some code duplication in a follow on cleanup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This untangles the DM_MAPIO_* values returned from ->clone_and_map_rq
from the error codes used by the block layer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Instead of returning either a DM_ENDIO_* constant or an error code, add
a new DM_ENDIO_DONE value that means keep errno as is. This allows us
to easily keep the existing error code in case where we can't push back,
and it also preparares for the new block level status codes with strict
type checking.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 6f287ca(md/raid10: reset the 'first' at the end of loop) ignores
a case in reshape, the first rdev could be a spare disk, which shouldn't
be accounted as the first disk since it doesn't include the offset info.
Fix: 6f287ca(md/raid10: reset the 'first' at the end of loop)
Cc: Guoqing Jiang <gqjiang@suse.com>
Cc: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
dm-bufio checks a watermark when it allocates a new buffer in
__bufio_new(). However, it doesn't check the watermark when the user
changes /sys/module/dm_bufio/parameters/max_cache_size_bytes.
This may result in a problem - if the watermark is high enough so that
all possible buffers are allocated and if the user lowers the value of
"max_cache_size_bytes", the watermark will never be checked against the
new value because no new buffer would be allocated.
To fix this, change __evict_old_buffers() so that it checks the
watermark. __evict_old_buffers() is called every 30 seconds, so if the
user reduces "max_cache_size_bytes", dm-bufio will react to this change
within 30 seconds and decrease memory consumption.
Depends-on: 1b0fb5a5b2 ("dm bufio: avoid a possible ABBA deadlock")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
__get_memory_limit() tests if dm_bufio_cache_size changed and calls
__cache_size_refresh() if it did. It takes dm_bufio_clients_lock while
it already holds the client lock. However, lock ordering is violated
because in cleanup_old_buffers() dm_bufio_clients_lock is taken before
the client lock.
This results in a possible deadlock and lockdep engine warning.
Fix this deadlock by changing mutex_lock() to mutex_trylock(). If the
lock can't be taken, it will be re-checked next time when a new buffer
is allocated.
Also add "unlikely" to the if condition, so that the optimizer assumes
that the condition is false.
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull block layer updates from Jens Axboe:
- Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
was initially a fork of CFQ, but subsequently changed to implement
fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
to be used on desktop type single drives, providing good fairness.
From Paolo.
- Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
using a scalable token based algorithm that throttles IO based on
live completion IO stats, similary to blk-wbt. From Omar.
- A series from Jan, moving users to separately allocated backing
devices. This continues the work of separating backing device life
times, solving various problems with hot removal.
- A series of updates for lightnvm, mostly from Javier. Includes a
'pblk' target that exposes an open channel SSD as a physical block
device.
- A series of fixes and improvements for nbd from Josef.
- A series from Omar, removing queue sharing between devices on mostly
legacy drivers. This helps us clean up other bits, if we know that a
queue only has a single device backing. This has been overdue for
more than a decade.
- Fixes for the blk-stats, and improvements to unify the stats and user
windows. This both improves blk-wbt, and enables other users to
register a need to receive IO stats for a device. From Omar.
- blk-throttle improvements from Shaohua. This provides a scalable
framework for implementing scalable priotization - particularly for
blk-mq, but applicable to any type of block device. The interface is
marked experimental for now.
- Bucketized IO stats for IO polling from Stephen Bates. This improves
efficiency of polled workloads in the presence of mixed block size
IO.
- A few fixes for opal, from Scott.
- A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
From a variety of folks, mostly Sagi and James Smart.
- A series from Bart, improving our exposed info and capabilities from
the blk-mq debugfs support.
- A series from Christoph, cleaning up how handle WRITE_ZEROES.
- A series from Christoph, cleaning up the block layer handling of how
we track errors in a request. On top of being a nice cleanup, it also
shrinks the size of struct request a bit.
- Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
never used by platforms, and the latter has outlived it's usefulness.
- Various little bug fixes and cleanups from a wide variety of folks.
* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
block: hide badblocks attribute by default
blk-mq: unify hctx delay_work and run_work
block: add kblock_mod_delayed_work_on()
blk-mq: unify hctx delayed_run_work and run_work
nbd: fix use after free on module unload
MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
blk-mq-sched: alloate reserved tags out of normal pool
mtip32xx: use runtime tag to initialize command header
scsi: Implement blk_mq_ops.show_rq()
blk-mq: Add blk_mq_ops.show_rq()
blk-mq: Show operation, cmd_flags and rq_flags names
blk-mq: Make blk_flags_show() callers append a newline character
blk-mq: Move the "state" debugfs attribute one level down
blk-mq: Unregister debugfs attributes earlier
blk-mq: Only unregister hctxs for which registration succeeded
blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
blk-mq: Let blk_mq_debugfs_register() look up the queue name
blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
ide-pm: always pass 0 error to __blk_end_request_all
..
I/O errors triggered by multipathd incorrectly not enabling the no-flush
flag for DM_DEVICE_SUSPEND or DM_DEVICE_RESUME are hard to debug. Add
more logging to make it easier to debug this.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
No functional change but makes the code easier to read.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Instead of checking MPATHF_QUEUE_IF_NO_PATH,
MPATHF_SAVED_QUEUE_IF_NO_PATH and the no_flush flag to decide whether
or not to push back a request (or bio) if there are no paths available,
only clear MPATHF_QUEUE_IF_NO_PATH in queue_if_no_path() if no_flush has
not been set. The result is that only a single bit has to be tested in
the hot path to decide whether or not a request must be pushed back and
also that m->lock does not have to be taken in the hot path.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Introduce an enumeration type for the queue mode. This patch does
not change any functionality but makes the DM code easier to read.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Verify at runtime that __pg_init_all_paths() is called with
multipath.lock held if lockdep is enabled.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Ensure that the assumptions about the caller holding suspend_lock
are checked at runtime if lockdep is enabled.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The 'cache_size' argument of dm_block_manager_create() has never been
used. Remove it along with the definitions of the constants passed as
the 'cache_size' argument.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Otherwise the request-based DM blk-mq request_queue will be put into
service without being properly exported via sysfs.
Cc: stable@vger.kernel.org
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Requeuing a request immediately while path initialization is ongoing
causes high CPU usage, something that is undesired. Hence delay
requeuing while path initialization is in progress.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If blk_get_request() fails, check whether the failure is due to a path
being removed. If that is the case, fail the path by triggering a call
to fail_path(). This avoids that the following scenario can be
encountered while removing paths:
* CPU usage of a kworker thread jumps to 100%.
* Removing the DM device becomes impossible.
Delay requeueing if blk_get_request() returns -EBUSY or -EWOULDBLOCK,
and the queue is not dying, because in these cases immediate requeuing
is inappropriate.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In new barrier codes, raise_barrier waits if conf->nr_pending[idx] is not zero.
After all the conditions are true, the resync request can go on be handled. But
it adds conf->nr_pending[idx] again. The next resync request hit the same bucket
idx need to wait the resync request which is submitted before. The performance
of resync/recovery is degraded.
So we should use a new variable to count sync requests which are in flight.
I did a simple test:
1. Without the patch, create a raid1 with two disks. The resync speed:
Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
sdb 0.00 0.00 166.00 0.00 10.38 0.00 128.00 0.03 0.20 0.20 0.00 0.19 3.20
sdc 0.00 0.00 0.00 166.00 0.00 10.38 128.00 0.96 5.77 0.00 5.77 5.75 95.50
2. With the patch, the result is:
sdb 2214.00 0.00 766.00 0.00 185.69 0.00 496.46 2.80 3.66 3.66 0.00 1.03 79.10
sdc 0.00 2205.00 0.00 769.00 0.00 186.44 496.52 5.25 6.84 0.00 6.84 1.30 100.10
Suggested-by: Shaohua Li <shli@kernel.org>
Signed-off-by: Xiao Ni <xni@redhat.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
activate_path() is renamed to activate_path_work() which now calls
activate_or_offline_path(). activate_or_offline_path() will be used
by the next commit.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When calling a dm ioctl that doesn't process any data
(IOCTL_FLAGS_NO_PARAMS), the contents of the data field in struct
dm_ioctl are left initialized. Current code is incorrectly extending
the size of data copied back to user, causing the contents of kernel
stack to be leaked to user. Fix by only copying contents before data
and allow the functions processing the ioctl to override.
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Salido <salidoa@google.com>
Reviewed-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The log2 of sectors_per_block was already calculated, so we don't have
to use the ilog2 function.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
There is no need to have a duplication of the generic library, i.e. hex2bin().
Replace the open coded variant.
Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Now that all the producers and consumers of dax interfaces have been
converted to using dax_operations on a dax_device, remove the block
device direct_access enabling.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Arrange for dm to lookup the dax services available from member devices.
Update the dax-capable targets, linear and stripe, to route dax
operations to the underlying device. Changes the target-internal
->direct_access() method to more closely align with the dax_operations
->direct_access() calling convention.
Cc: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
dm-crypt used to use separate crypto transforms for each CPU, but this
is no longer the case. To avoid confusion, fix up obsolete comments and
rename setup_essiv_cpu().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
We can clear 'WantReplacement' flag directly no
matter it's replacement existed or not since the
semantic is same as before.
Also since the disk is removed from array, then
it is straightforward to remove 'WantReplacement'
flag and the comments in raid10/5 can be removed
as well.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Use of the synchronous digest API limits dm-verity to using pure
CPU based algorithm providers and rules out the use of off CPU
algorithm providers which are normally asynchronous by nature,
potentially freeing CPU cycles.
This can reduce performance per Watt in situations such as during
boot time when a lot of concurrent file accesses are made to the
protected volume.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
CC: Eric Biggers <ebiggers3@gmail.com>
CC: Ondrej Mosnáček <omosnacek+linux-crypto@gmail.com>
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Running dm-crypt with workqueues at the standard priority results in IO
competing for CPU time with standard user apps, which can lead to
pipeline bubbles and seriously degraded performance. Move to using
WQ_HIGHPRI workqueues to protect against that.
Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The message "key wipe" used to wipe real key stored in crypto layer by
rewriting it with zeroes. Since commit 28856a9 ("crypto: xts -
consolidate sanity check for keys") this no longer works in FIPS mode
for XTS.
While running in FIPS mode the crypto key part has to differ from the
tweak key.
Fixes: 28856a9 ("crypto: xts - consolidate sanity check for keys")
Cc: stable@vger.kernel.org
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If blk_get_request() returns ENODEV then multipath_clone_and_map()
causes a request to be requeued immediately. This can cause a kworker
thread to spend 100% of the CPU time of a single core in
__blk_mq_run_hw_queue() and also can cause device removal to never
finish.
Avoid this by only requeuing after a delay if blk_get_request() fails.
Additionally, reduce the requeue delay.
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When committing era metadata to disk, it doesn't always save the latest
spacemap metadata root in superblock. Due to this, metadata is getting
corrupted sometimes when reopening the device. The correct order of update
should be, pre-commit (shadows spacemap root), save the spacemap root
(newly shadowed block) to in-core superblock and then the final commit.
Cc: stable@vger.kernel.org
Signed-off-by: Somasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm_btree_find_lowest_key() is giving incorrect results. find_key()
traverses the btree correctly for finding the highest key, but there is
an error in the way it traverses the btree for retrieving the lowest
key. dm_btree_find_lowest_key() fetches the first key of the rightmost
block of the btree instead of fetching the first key from the leftmost
block.
Fix this by conditionally passing the correct parameter to value64()
based on the @find_highest flag.
Cc: stable@vger.kernel.org
Signed-off-by: Erez Zadok <ezk@fsl.cs.sunysb.edu>
Signed-off-by: Vinothkumar Raja <vinraja@cs.stonybrook.edu>
Signed-off-by: Nidhi Panpalia <npanpalia@cs.stonybrook.edu>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The extra pair of parantheses is not needed and causes clang to generate
warnings about the DM_DEV_CREATE_CMD comparison in validate_params().
Also remove another double parentheses that doesn't cause a warning.
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This dummy structure definition was required for RCU macros, but it
isn't required anymore, so delete it.
The dummy definition confuses the crash tool, see:
https://www.redhat.com/archives/dm-devel/2017-April/msg00197.html
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Previously, dm-crypt could use blocks composed of multiple 512b sectors
but it created integrity profile for each 512b sector (it padded it with
zeroes). Fix dm-crypt so that the integrity profile is sent for each
block not each sector.
The user must use the same block size in the DM crypt and integrity
targets.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The DM integrity block size can now be 512, 1k, 2k or 4k. Using larger
blocks reduces metadata handling overhead. The block size can be
configured at table load time using the "block_size:<value>" option;
where <value> is expressed in bytes (defult is still 512 bytes).
It is safe to use larger block sizes with DM integrity, because the
DM integrity journal makes sure that the whole block is updated
atomically even if the underlying device doesn't support atomic writes
of that size (e.g. 4k block ontop of a 512b device).
Depends-on: 2859323e ("block: fix blk_integrity_register to use template's interval_exp if not 0")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Some coding style changes.
Fix a bug that the array test_tag has insufficient size if the digest
size of internal has is bigger than the tag size.
The function __fls is undefined for zero argument, this patch fixes
undefined behavior if the user sets zero interleave_sectors.
Fix the limit of optional arguments to 8.
Don't allocate crypt_data on the stack to avoid a BUG with debug kernel.
Rename all optional argument names to have underscores rather than
dashes.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
A dm-crypt on dm-integrity device incorrectly advertises an integrity
profile on the DM crypt device. It can be seen in the files
"/sys/block/dm-*/integrity/*" that both dm-integrity and dm-crypt target
advertise the integrity profile. That is incorrect, only the
dm-integrity target should advertise the integrity profile.
A general problem in DM is that if we have a DM device that depends on
another device with an integrity profile, the upper device will always
advertise the integrity profile, even when the target driver doesn't
support handling integrity data.
Most targets don't support integrity data, so we provide a whitelist of
targets that support it (linear, delay and striped). The targets that
support passing integrity data to the lower device are marked with the
flag DM_TARGET_PASSES_INTEGRITY. The DM core will now advertise
integrity data on a DM device only if all the targets support the
integrity data.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Also remove some unnecessary use of uninitialized_var().
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
A queue is declared and get from the disk of the array, but it's not
used anywhere. So removing it from the source.
Signed-off-by: Lidong Zhong <lzhong@suse.com>
Acted-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
1/ If an array has any read-only devices when it is started,
the array itself must be read-only
2/ A read-only device cannot be added to an array after it is
started.
3/ Setting an array to read-write should not succeed
if any member devices are read-only
Reported-and-Tested-by: Nanda Kishore Chinnaram <Nanda_Kishore_Chinna@dell.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Allocate a dax_device to represent the capacity of a device-mapper
instance. Provide a ->direct_access() method via the new dax_operations
indirection that mirrors the functionality of the current direct_access
support via block_device_operations. Once fs/dax.c has been converted
to use dax_operations the old dm_blk_direct_access() will be removed.
A new helper dm_dax_get_live_target() is introduced to separate some of
the dm-specifics from the direct_access implementation.
This enabling is only for the top-level dm representation to upper
layers. Converting target direct_access implementations is deferred to a
separate patch.
Cc: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that all drivers that call blk_mq_complete_requests have a
->complete callback we can remove the direct call to blk_mq_end_request,
as well as the error argument to blk_mq_complete_request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
We'll get all proper errors reported through ->end_io and ->errors will
go away soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
dm never uses rq->errors, so there is no need to pass an error argument
to blk_mq_complete_request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since nr_queued is changed, we need to call wake_up here
if the array is already frozen and waiting for condition
"nr_pending == nr_queued + extra" to be true.
And commit 824e47dadd ("RAID1: avoid unnecessary spin
locks in I/O barrier code") which has already added the
wake_up for raid1.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
We know that 'bm_lockres' is NULL here, so 'lockres_free(bm_lockres)' is a
no-op. According to resource handling in case of error a few lines below,
it is likely that 'bitmap_free(bitmap)' was expected instead.
Fixes: b98938d16a ("md-cluster: introduce cluster_check_sync_size")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
md allows a new array device to be created by simply
opening a device file. This make it difficult to
remove the device and udev is likely to open the device file
as part of processing the REMOVE event.
There is an alternate mechanism for creating arrays
by writing to the new_array module parameter.
When using tools that work with this parameter, it is
best to disable the old semantics.
This new module parameter allows that.
Signed-off-by: NeilBrown <neilb@suse.com>
Acted-by: Coly Li <colyli@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
The intention when creating the "new_array" parameter and the
possibility of having array names line "md_HOME" was to transition
away from the old way of creating arrays and to eventually only use
this new way.
The "old" way of creating array is to create a device node in /dev
and then open it. The act of opening creates the array.
This is problematic because sometimes the device node can be opened
when we don't want to create an array. This can easily happen
when some rule triggered by udev looks at a device as it is being
destroyed. The node in /dev continues to exist for a short period
after an array is stopped, and opening it during this time recreates
the array (as an inactive array).
Unfortunately no clear plan for the transition was created. It is now
time to fix that.
This patch allows devices with numeric names, like "md999" to be
created by writing to "new_array". This will only work if the minor
number given is not already in use. This will allow mdadm to
support the creation of arrays with numbers > 511 (currently not
possible) by writing to new_array.
mdadm can, at some point, use this approach to create *all* arrays,
which will allow the transition to only using the new-way.
Signed-off-by: NeilBrown <neilb@suse.com>
Acted-by: Coly Li <colyli@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Allocate both struct ppl_io_unit and its header_page from a shared
mempool to avoid a possible deadlock. Implement allocate and free
functions for the mempool, remove the second pool for allocating
header_page. The header_pages are now freed with their io_units, not
when the ppl bio completes. Also, use GFP_NOWAIT instead of GFP_ATOMIC
for allocating ppl_io_unit because we can handle failed allocations and
there is no reason to utilize emergency reserves.
Suggested-by: NeilBrown <neilb@suse.com>
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
raid0_make_request() should use a private bio_set rather than the
shared fs_bio_set, which is only meant for filesystems to use.
raid0_make_request() shouldn't loop around using the bio_set
multiple times as that can deadlock.
So use mddev->bio_set and pass the tail to generic_make_request()
instead of looping on it.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
linear_make_request() uses fs_bio_set, which is meant for filesystems
to use, and loops, possible allocating from the same bio set multiple
times.
These behaviors can theoretically cause deadlocks, though as
linear requests are hardly ever split, it is unlikely in practice.
Change to use mddev->bio_set - otherwise unused for linear, and submit
the tail of a split request to generic_make_request() for it to
handle.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
chunk_aligned_read() currently uses fs_bio_set - which is meant for
filesystems to use - and loops if multiple splits are needed, which is
not best practice.
As this is only used for READ requests, not writes, it is unlikely
to cause a problem. However it is best to be consistent in how
we split bios, and to follow the pattern used in raid1/raid10.
So create a private bioset, bio_split, and use it to perform a single
split, submitting the remainder to generic_make_request() for later
processing.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
handle_read_error() duplicates a lot of the work that raid10_read_request()
does, so it makes sense to just use that function.
handle_read_error() relies on the same r10bio being re-used so that,
in the case of a read-only array, setting IO_BLOCKED in r1bio->devs[].bio
ensures read_balance() won't re-use that device.
So when called from raid10_make_request() we clear that array, but not
when called from handle_read_error().
Two parts of handle_read_error() that need to be preserved are the warning
message it prints, so they are conditionally added to
raid10_read_request(). If the failing rdev can be found, messages
are printed. Otherwise they aren't.
Not that as rdev_dec_pending() has already been called on the failing
rdev, we need to use rcu_read_lock() to get a new reference from
the conf. We only use this to get the name of the failing block device.
With this change, we no longer need inc_pending().
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
raid10 splits requests in two different ways for two different
reasons.
First, bio_split() is used to ensure the bio fits with a chunk.
Second, multiple r10bio structures are allocated to represent the
different sections that need to go to different devices, to avoid
known bad blocks.
This can be simplified to just use bio_split() once, and not to use
multiple r10bios.
We delay the split until we know a maximum bio size that can
be handled with a single r10bio, and then split the bio and queue
the remainder for later handling.
As with raid1, we allocate a new bio_set to help with the splitting.
It is not correct to use fs_bio_set in a device driver.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
flush_pending_writes() and raid1_unplug() each contain identical
copies of a fairly large slab of code. So factor that out into
new flush_bio_list() to simplify maintenance.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
handle_read_error() duplicates a lot of the work that raid1_read_request()
does, so it makes sense to just use that function.
This doesn't quite work as handle_read_error() relies on the same r1bio
being re-used so that, in the case of a read-only array, setting
IO_BLOCKED in r1bio->bios[] ensures read_balance() won't re-use
that device.
So we need to allow a r1bio to be passed to raid1_read_request(), and to
have that function mostly initialise the r1bio, but leave the bios[]
array untouched.
Two parts of handle_read_error() that need to be preserved are the warning
message it prints, so they are conditionally added to raid1_read_request().
Note that this highlights a minor bug on alloc_r1bio(). It doesn't
initalise the bios[] array, so it is possible that old content is there,
which might cause read_balance() to ignore some devices with no good reason.
With this change, we no longer need inc_pending(), or the sectors_handled
arg to alloc_r1bio().
As handle_read_error() is called from raid1d() and allocates memory,
there is tiny chance of a deadlock. All element of various pools
could be queued waiting for raid1 to handle them, and there may be no
extra memory free.
Achieving guaranteed forward progress would probably require a second
thread and another mempool. Instead of that complexity, add
__GFP_HIGH to any allocations when read1_read_request() is called
from raid1d.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Now that we always always pass an offset of 0 and a size
that matches the bio to alloc_behind_master_bio(),
we can remove the offset/size args and simplify the code.
We could probably remove bio_copy_data_partial() too.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
raid1 currently splits requests in two different ways for
two different reasons.
First, bio_split() is used to ensure the bio fits within a
resync accounting region.
Second, multiple r1bios are allocated for each bio to handle
the possiblity of known bad blocks on some devices.
This can be simplified to just use bio_split() once, and not
use multiple r1bios.
We delay the split until we know a maximum bio size that can
be handled with a single r1bio, and then split the bio and
queue the remainder for later handling.
This avoids all loops inside raid1.c request handling. Just
a single read, or a single set of writes, is submitted to
lower-level devices for each bio that comes from
generic_make_request().
When the bio needs to be split, generic_make_request() will
do the necessary looping and call md_make_request() multiple
times.
raid1_make_request() no longer queues request for raid1 to handle,
so we can remove that branch from the 'if'.
This patch also creates a new private bio_set
(conf->bio_split) for splitting bios. Using fs_bio_set
is wrong, as it is meant to be used by filesystems, not
block devices. Using it inside md can lead to deadlocks
under high memory pressure.
Delete unused variable in raid1_write_request() (Shaohua)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
In case of read-modify-write, partial partity is the same as the result
of ops_run_prexor5(), so we can just copy sh->dev[pd_idx].page into
sh->ppl_page instead of calculating it again.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Use resize_stripes() instead of raid5_reset_stripe_cache() to allocate
or free sh->ppl_page at runtime for all stripes in the stripe cache.
raid5_reset_stripe_cache() required suspending the mddev and could
deadlock because of GFP_KERNEL allocations.
Move the 'newsize' check to check_reshape() to allow reallocating the
stripes with the same number of disks. Allocate sh->ppl_page in
alloc_stripe() instead of grow_buffers(). Pass 'struct r5conf *conf' as
a parameter to alloc_stripe() because it is needed to check whether to
allocate ppl_page. Add free_stripe() and use it to free stripes rather
than directly call kmem_cache_free(). Also free sh->ppl_page in
free_stripe().
Set MD_HAS_PPL at the end of ppl_init_log() instead of explicitly
setting it in advance and add another parameter to log_init() to allow
calling ppl_init_log() without the bit set. Don't try to calculate
partial parity or add a stripe to log if it does not have ppl_page set.
Enabling ppl can now be performed without suspending the mddev, because
the log won't be used until new stripes are allocated with ppl_page.
Calling mddev_suspend/resume is still necessary when disabling ppl,
because we want all stripes to finish before stopping the log, but
resize_stripes() can be called after mddev_resume() when ppl is no
longer active.
Suggested-by: NeilBrown <neilb@suse.com>
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Use a single no_mem_stripes list instead of per member device lists for
handling stripes that need retrying in case of failed io_unit
allocation. Because io_units are allocated from a memory pool shared
between all member disks, the no_mem_stripes list should be checked when
an io_unit for any member is freed. This fixes a deadlock that could
happen if there are stripes in more than one no_mem_stripes list.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
fix_sync_read_error() modifies a bio on a newly faulty
device by setting bi_end_io to end_sync_write.
This ensure that put_buf() will still call rdev_dec_pending()
as required, but makes sure that subsequent code in
fix_sync_read_error() doesn't try to read from the device.
Unfortunately this interacts badly with sync_request_write()
which assumes that any bio with bi_end_io set to non-NULL
other than end_sync_read is safe to write to.
As the device is now faulty it doesn't make sense to write.
As the bio was recently used for a read, it is "dirty"
and not suitable for immediate submission.
In particular, ->bi_next might be non-NULL, which will cause
generic_make_request() to complain.
Break this interaction by refusing to write to devices
which are marked as Faulty.
Reported-and-tested-by: Michael Wang <yun.wang@profitbricks.com>
Fixes: 2e52d449bc ("md/raid1: add failfast handling for reads.")
Cc: stable@vger.kernel.org (v4.10+)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
md.c: it needs to release the mddev lock before
the array_size_store() returns.
Fixes: ab5a98b132 ("md-cluster: change array_sectors and update size are not supported")
Signed-off-by: Zhilong Liu <zlliu@suse.com>
Reviewed-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
if called md_set_readonly and set MD_CLOSING bit, the mddev cannot
be opened any more due to the MD_CLOING bit wasn't cleared. Thus it
needs to be cleared in md_ioctl after any call to md_set_readonly()
or do_md_stop().
Signed-off-by: NeilBrown <neilb@suse.com>
Fixes: af8d8e6f03 ("md: changes for MD_STILL_CLOSED flag")
Cc: stable@vger.kernel.org (v4.9+)
Signed-off-by: Zhilong Liu <zlliu@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
We need to set "first = 0' at the end of rdev_for_each
loop, so we can get the array's min_offset_diff correctly
otherwise min_offset_diff just means the last rdev's
offset diff.
Suggested-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When recoverying a single missing/failed device in a RAID6,
those stripes where the Q block is on the missing device are
handled a bit differently. In these cases it is easy to
check that the P block is correct, so we do. This results
in the P block be destroy. Consequently the P block needs
to be read a second time in order to compute Q. This causes
lots of seeks and hurts performance.
It shouldn't be necessary to re-read P as it can be computed
from the DATA. But we only compute blocks on missing
devices, since c337869d95 ("md: do not compute parity
unless it is on a failed drive").
So relax the change made in that commit to allow computing
of the P block in a RAID6 which it is the only missing that
block.
This makes RAID6 recovery run much faster as the disk just
"before" the recovering device is no longer seeking
back-and-forth.
Reported-by-tested-by: Brad Campbell <lists2009@fnarfbargle.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Pull block fixes from Jens Axboe:
"Here's a pull request for 4.11-rc, fixing a set of issues mostly
centered around the new scheduling framework. These have been brewing
for a while, but split up into what we absolutely need in 4.11, and
what we can defer until 4.12. These are well tested, on both single
queue and multiqueue setups, and with and without shared tags. They
fix several hangs that have happened in testing.
This is obviously larger than I would have preferred at this point in
time, but I don't think we can shave much off this and still get the
desired results.
In detail, this pull request contains:
- a set of five fixes for NVMe, mostly from Christoph and one from
Roland.
- a series from Bart, fixing issues with dm-mq and SCSI shared tags
and scheduling. Note that one of those patches commit messages may
read like an optimization, but it is in fact an important fix for
queue restarts in particular.
- a series from Omar, most importantly fixing a hang with multiple
hardware queues when we fail to get a driver tag. Another important
fix in there is for resizing hardware queues, which nbd does when
handling multiple sockets for one connection.
- fixing an imbalance in putting the ctx for hctx request allocations
from Minchan"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq: Restart a single queue if tag sets are shared
dm rq: Avoid that request processing stalls sporadically
scsi: Avoid that SCSI queues get stuck
blk-mq: Introduce blk_mq_delay_run_hw_queue()
blk-mq: remap queues when adding/removing hardware queues
blk-mq-sched: fix crash in switch error path
blk-mq-sched: set up scheduler tags when bringing up new queues
blk-mq-sched: refactor scheduler initialization
blk-mq: use the right hctx when getting a driver tag fails
nvmet: fix byte swap in nvmet_parse_io_cmd
nvmet: fix byte swap in nvmet_execute_write_zeroes
nvmet: add missing byte swap in nvmet_get_smart_log
nvme: add missing byte swap in nvme_setup_discard
nvme: Correct NVMF enum values to match NVMe-oF rev 1.0
block: do not put mq context in blk_mq_alloc_request_hctx
Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can
kill this hack.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
It seems like the code currently passes whatever it was using for writes
to WRITE SAME. Just switch it to WRITE ZEROES, although that doesn't
need any payload.
Untested, and confused by the code, maybe someone who understands it
better than me can help..
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Copy & paste from the REQ_OP_WRITE_SAME code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Fix up do_region to not allocate a bio_vec for discards. We've
got rid of the discard payload allocated by the caller years ago.
Obviously this wasn't actually harmful given how long it's been
there, but it's still good to avoid the pointless allocation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Copy & paste from the REQ_OP_WRITE_SAME code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
We've added a considerable amount of fixes for stalls and issues
with the blk-mq scheduling in the 4.11 series since forking
off the for-4.12/block branch. We need to do improvements on
top of that for 4.12, so pull in the previous fixes to make
our lives easier going forward.
Signed-off-by: Jens Axboe <axboe@fb.com>
While running the srp-test software I noticed that request
processing stalls sporadically at the beginning of a test, namely
when mkfs is run against a dm-mpath device. Every time when that
happened the following command was sufficient to resume request
processing:
echo run >/sys/kernel/debug/block/dm-0/state
This patch avoids that such request processing stalls occur. The
test I ran is as follows:
while srp-test/run_tests -d -r 30 -t 02-mq; do :; done
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Jens Axboe <axboe@fb.com>
- A stable@ fix for raid target's raid1 support (when no bitmap is used)
- A 4.11 cache metadata v2 format fix to properly test blocks are clean
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Merge tag 'dm-4.11-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- two stable fixes for the verity target's FEC support
- a stable fix for raid target's raid1 support (when no bitmap is used)
- a 4.11 cache metadata v2 format fix to properly test blocks are clean
* tag 'dm-4.11-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm verity fec: fix bufio leaks
dm raid: fix NULL pointer dereference for raid1 without bitmap
dm cache metadata: fix metadata2 format's blocks_are_clean_separate_dirty
dm verity fec: limit error correction recursion
Currently only dm and md/raid5 bios trigger
trace_block_bio_complete(). Now that we have bio_chain() and
bio_inc_remaining(), it is not possible, in general, for a driver to
know when the bio is really complete. Only bio_endio() knows that.
So move the trace_block_bio_complete() call to bio_endio().
Now trace_block_bio_complete() pairs with trace_block_bio_queue().
Any bio for which a 'queue' event is traced, will subsequently
generate a 'complete' event.
There are a few cases where completion tracing is not wanted.
1/ If blk_update_request() has already generated a completion
trace event at the 'request' level, there is no point generating
one at the bio level too. In this case the bi_sector and bi_size
will have changed, so the bio level event would be wrong
2/ If the bio hasn't actually been queued yet, but is being aborted
early, then a trace event could be confusing. Some filesystems
call bio_endio() but do not want tracing.
3/ The bio_integrity code interposes itself by replacing bi_end_io,
then restoring it and calling bio_endio() again. This would produce
two identical trace events if left like that.
To handle these, we introduce a flag BIO_TRACE_COMPLETION and only
produce the trace event when this is set.
We address point 1 above by clearing the flag in blk_update_request().
We address point 2 above by only setting the flag when
generic_make_request() is called.
We address point 3 above by clearing the flag after generating a
completion event.
When bio_split() is used on a bio, particularly in blk_queue_split(),
there is an extra complication. A new bio is split off the front, and
may be handle directly without going through generic_make_request().
The old bio, which has been advanced, is passed to
generic_make_request(), so it will trigger a trace event a second
time.
Probably the best result when a split happens is to see a single
'queue' event for the whole bio, then multiple 'complete' events - one
for each component. To achieve this was can:
- copy the BIO_TRACE_COMPLETION flag to the new bio in bio_split()
- avoid generating a 'queue' event if BIO_TRACE_COMPLETION is already set.
This way, the split-off bio won't create a queue event, the original
won't either even if it re-submitted to generic_make_request(),
but both will produce completion events, each for their own range.
So if generic_make_request() is called (which generates a QUEUED
event), then bi_endio() will create a single COMPLETE event for each
range that the bio is split into, unless the driver has explicitly
requested it not to.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Buffers read through dm_bufio_read() were not released in all code paths.
Fixes: a739ff3f54 ("dm verity: add support for forward error correction")
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
By ignoring the sentinels the cleaner policy is able to write-back dirty
cache data much faster. There is no reason to respect the sentinels,
which denote that a block was changed recently, when using the cleaner
policy given that the cleaner is tasked with writing back all dirty
data.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When loading metadata make sure to set/clear the dirty bits in the cache
core's dirty_bitset as well as the policy.
Otherwise the cache core is unaware that any blocks were dirty when the
cache was last shutdown. A very serious side-effect being that the
cleaner policy would therefore never be tasked with writing back dirty
data from a cache that was in writeback mode (e.g. when switching from
smq policy to cleaner policy when decommissioning a writeback cache).
This fixes a serious data corruption bug associated with writeback mode.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Constify all instances of blk_mq_ops, as they are never modified.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since the commit 0cf4503174 ("dm raid: add support for the MD RAID0
personality"), the dm-raid subsystem can activate a RAID-0 array.
Therefore, add MD_RAID0 to the dependencies of DM_RAID, so that MD_RAID0
will be selected when DM_RAID is selected.
Fixes: 0cf4503174 ("dm raid: add support for the MD RAID0 personality")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This patch kills the warning reported on powerpc_pseries,
and actually we don't need the initialization.
After merging the md tree, today's linux-next build (powerpc
pseries_le_defconfig) produced this warning:
drivers/md/raid1.c: In function 'raid1d':
drivers/md/raid1.c:2172:9: warning: 'page_len$' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (memcmp(page_address(ppages[j]),
^
drivers/md/raid1.c:2160:7: note: 'page_len$' was declared here
int page_len[RESYNC_PAGES];
^
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
URLs to ftp.kernel.org are still exist though the service is closed [0].
This commit fixes the URLs to use www.kernel.org instead.
[0] https://www.kernel.org/shutting-down-ftp-services.html
Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
When journal device of an array fails, the array is forced into read-only
mode. To make the array normal without adding another journal device, we
need to remove journal _feature_ from the array.
This patch allows remove journal _feature_ from an array, For journal
existing journal should be either missing or faulty.
To remove journal feature, it is necessary to remove the journal device
first:
mdadm --fail /dev/md0 /dev/sdb
mdadm: set /dev/sdb faulty in /dev/md0
mdadm --remove /dev/md0 /dev/sdb
mdadm: hot removed /dev/sdb from /dev/md0
Then the journal feature can be removed by echoing into the sysfs file:
cat /sys/block/md0/md/consistency_policy
journal
echo resync > /sys/block/md0/md/consistency_policy
cat /sys/block/md0/md/consistency_policy
resync
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Commit 63c32ed4af ("dm raid: add raid4/5/6 journaling support") added
journal support to close the raid4/5/6 "write hole" -- in terms of
writethrough caching.
Introduce a "journal_mode" feature and use the new
r5c_journal_mode_set() API to add support for switching the journal
device's cache mode between write-through (the current default) and
write-back.
NOTE: If the journal device is not layered on resilent storage and it
fails, write-through mode will cause the "write hole" to reoccur. But
if the journal fails while in write-back mode it will cause data loss
for any dirty cache entries unless resilent storage is used for the
journal.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 3a1c1ef2f ("dm raid: enhance status interface and fixup
takeover/raid0") added new table line arguments and introduced an
ordering flaw. The sequence of the raid10_copies and raid10_format
raid parameters got reversed which causes lvm2 userspace to fail by
falsely assuming a changed table line.
Sequence those 2 parameters as before so that old lvm2 can function
properly with new kernels by adjusting the table line output as
documented in Documentation/device-mapper/dm-raid.txt.
Also, add missing version 1.10.1 highlight to the documention.
Fixes: 3a1c1ef2f ("dm raid: enhance status interface and fixup takeover/raid0")
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 2ded370373 ("md/r5cache: State machine for raid5-cache write
back mode") added support for "write-back" caching on the raid journal
device.
In order to allow the dm-raid target to switch between the available
"write-through" and "write-back" modes, provide a new
r5c_journal_mode_set() API.
Use the new API in existing r5c_journal_mode_store()
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Acked-by: Shaohua Li <shli@fb.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The payload->header.type and payload->size are little-endian, so just
convert them to the right byte order.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: <stable@vger.kernel.org> #v4.10+
Signed-off-by: Shaohua Li <shli@fb.com>
discard request doesn't have data attached, so it's meaningless to
allocate memory and copy from original bio for behind IO. And the copy
is bogus because bio_copy_data_partial can't handle discard request.
We don't support writesame/writezeros request so far.
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
sector_div is very slow, so we introduce a variable sector_shift and
use shift instead of sector_div.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In recovery mode, we don't:
- replay the journal
- check checksums
- allow writes to the device
This mode can be used as a last resort for data recovery. The
motivation for recovery mode is that when there is a single error in the
journal, the user should not lose access to the whole device.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add optional "sector_size" parameter that specifies encryption sector
size (atomic unit of block device encryption).
Parameter can be in range 512 - 4096 bytes and must be power of two.
For compatibility reasons, the maximal IO must fit into the page limit,
so the limit is set to the minimal page size possible (4096 bytes).
NOTE: this device cannot yet be handled by cryptsetup if this parameter
is set.
IV for the sector is calculated from the 512 bytes sector offset unless
the iv_large_sectors option is used.
Test script using dmsetup:
DEV="/dev/sdb"
DEV_SIZE=$(blockdev --getsz $DEV)
KEY="9c1185a5c5e9fc54612808977ee8f548b2258d31ddadef707ba62c166051b9e3cd0294c27515f2bccee924e8823ca6e124b8fc3167ed478bca702babe4e130ac"
BLOCK_SIZE=4096
# dmsetup create test_crypt --table "0 $DEV_SIZE crypt aes-xts-plain64 $KEY 0 $DEV 0 1 sector_size:$BLOCK_SIZE"
# dmsetup table --showkeys test_crypt
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
For the new authenticated encryption we have to support generic composed
modes (combination of encryption algorithm and authenticator) because
this is how the kernel crypto API accesses such algorithms.
To simplify the interface, we accept an algorithm directly in crypto API
format. The new format is recognised by the "capi:" prefix. The
dmcrypt internal IV specification is the same as for the old format.
The crypto API cipher specifications format is:
capi:cipher_api_spec-ivmode[:ivopts]
Examples:
capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256)
capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64)
Examples of authenticated modes:
capi:gcm(aes)-random
capi:authenc(hmac(sha256),xts(aes))-random
capi:rfc7539(chacha20,poly1305)-random
Authenticated modes can only be configured using the new cipher format.
Note that this format allows user to specify arbitrary combinations that
can be insecure. (Policy decision is done in cryptsetup userspace.)
Authenticated encryption algorithms can be of two types, either native
modes (like GCM) that performs both encryption and authentication
internally, or composed modes where user can compose AEAD with separate
specification of encryption algorithm and authenticator.
For composed mode with HMAC (length-preserving encryption mode like an
XTS and HMAC as an authenticator) we have to calculate HMAC digest size
(the separate authentication key is the same size as the HMAC digest).
Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get
HMAC algorithm and retrieve digest size from it.
Also, for HMAC composed mode we need to parse the crypto API string to
get the cipher mode nested in the specification. For native AEAD mode
(like GCM), we can use crypto_tfm_alg_name() API to get the cipher
specification.
Because the HMAC composed mode is not processed the same as the native
AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and
"hmac" specification for the table integrity argument is removed.
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Allow the use of per-sector metadata, provided by the dm-integrity
module, for integrity protection and persistently stored per-sector
Initialization Vector (IV). The underlying device must support the
"DM-DIF-EXT-TAG" dm-integrity profile.
The per-bio integrity metadata is allocated by dm-crypt for every bio.
Example of low-level mapping table for various types of use:
DEV=/dev/sdb
SIZE=417792
# Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key
SIZE_INT=389952
dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0"
dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \
11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \
00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \
0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)"
# AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs
# GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space)
SIZE_INT=393024
dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0"
dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \
11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \
0 /dev/mapper/x 0 1 integrity:28:aead"
# Random IV only for XTS mode (no integrity protection but provides atomic random sector change)
SIZE_INT=401272
dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0"
dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \
11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \
0 /dev/mapper/x 0 1 integrity:16:none"
# Random IV with XTS + HMAC integrity protection
SIZE_INT=377656
dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0"
dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \
11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \
00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \
0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)"
Both AEAD and HMAC protection authenticates not only data but also
sector metadata.
HMAC protection is implemented through autenc wrapper (so it is
processed the same way as an authenticated mode).
In HMAC mode there are two keys (concatenated in dm-crypt mapping
table). First is the encryption key and the second is the key for
authentication (HMAC). (It is userspace decision if these keys are
independent or somehow derived.)
The sector request for AEAD/HMAC authenticated encryption looks like this:
|----- AAD -------|------ DATA -------|-- AUTH TAG --|
| (authenticated) | (auth+encryption) | |
| sector_LE | IV | sector in/out | tag in/out |
For writes, the integrity fields are calculated during AEAD encryption
of every sector and stored in bio integrity fields and sent to
underlying dm-integrity target for storage.
For reads, the integrity metadata is verified during AEAD decryption of
every sector (they are filled in by dm-integrity, but the integrity
fields are pre-allocated in dm-crypt).
There is also an experimental support in cryptsetup utility for more
friendly configuration (part of LUKS2 format).
Because the integrity fields are not valid on initial creation, the
device must be "formatted". This can be done by direct-io writes to the
device (e.g. dd in direct-io mode). For now, there is available trivial
tool to do this, see: https://github.com/mbroz/dm_int_tools
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: Vashek Matyas <matyas@fi.muni.cz>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The dm-integrity target emulates a block device that has additional
per-sector tags that can be used for storing integrity information.
A general problem with storing integrity tags with every sector is that
writing the sector and the integrity tag must be atomic - i.e. in case of
crash, either both sector and integrity tag or none of them is written.
To guarantee write atomicity the dm-integrity target uses a journal. It
writes sector data and integrity tags into a journal, commits the journal
and then copies the data and integrity tags to their respective location.
The dm-integrity target can be used with the dm-crypt target - in this
situation the dm-crypt target creates the integrity data and passes them
to the dm-integrity target via bio_integrity_payload attached to the bio.
In this mode, the dm-crypt and dm-integrity targets provide authenticated
disk encryption - if the attacker modifies the encrypted device, an I/O
error is returned instead of random data.
The dm-integrity target can also be used as a standalone target, in this
mode it calculates and verifies the integrity tag internally. In this
mode, the dm-integrity target can be used to detect silent data
corruption on the disk or in the I/O path.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
All reshape I/O share pages from 1st copy device, so just use that pages
for avoiding direct access to bvec table in handle_reshape_read_error.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Now one page array is allocated for each resync bio, and we can
retrieve page from this table directly.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Now we allocate one page array for managing resync pages, instead
of using bio's vec table to do that, and the old way is very hacky
and won't work any more if multipage bvec is enabled.
The introduced cost is that we need to allocate (128 + 16) * copies
bytes per r10_bio, and it is fine because the inflight r10_bio for
resync shouldn't be much, as pointed by Shaohua.
Also bio_reset() in raid10_sync_request() and reshape_request()
are removed because all bios are freshly new now in these functions
and not necessary to reset any more.
This patch can be thought as cleanup too.
Suggested-by: Shaohua Li <shli@kernel.org>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
reshape read request is a bit special and requires one extra
bio which isn't allocated from r10buf_pool.
Refactor the .bi_end_io for read reshape, so that we can use
raid10's resync page mangement approach easily in the following
patches.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This patch improve handling of write behind in the following ways:
- introduce behind master bio to hold all write behind pages
- fast clone bios from behind master bio
- avoid to change bvec table directly
- use bio_copy_data() and make code more clean
Suggested-by: Shaohua Li <shli@fb.com>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The 'offset' local variable can't be changed inside the loop, so
move it out.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Now one page array is allocated for each resync bio, and we can
retrieve page from this table directly.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Now we allocate one page array for managing resync pages, instead
of using bio's vec table to do that, and the old way is very hacky
and won't work any more if multipage bvec is enabled.
The introduced cost is that we need to allocate (128 + 16) * raid_disks
bytes per r1_bio, and it is fine because the inflight r1_bio for
resync shouldn't be much, as pointed by Shaohua.
Also the bio_reset() in raid1_sync_request() is removed because
all bios are freshly new now and not necessary to reset any more.
This patch can be thought as a cleanup too
Suggested-by: Shaohua Li <shli@kernel.org>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This patch gets each page's reference of each bio for resync,
then r1buf_pool_free() gets simplified a lot.
The same policy has been taken in raid10's buf pool allocation/free
too.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Now resync I/O use bio's bec table to manage pages,
this way is very hacky, and may not work any more
once multipage bvec is introduced.
So introduce helpers and new data structure for
managing resync I/O pages more cleanly.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Both raid1 and raid10 share common resync
block size and page count, so move them into md.h.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
All bio_add_page() is for adding one page into resync bio,
which is big enough to hold RESYNC_PAGES pages, and
the current bio_add_page() doesn't check queue limit any more,
so it won't fail at all.
remove unused label (shaohua)
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Previously, we clone both bio and repl_bio in raid10_write_request,
then add the cloned bio to plug->pending or conf->pending_bio_list
based on plug or not, and most of the logics are same for the two
conditions.
So introduce raid10_write_one_disk for it, and use replacement parameter
to distinguish the difference. No functional changes in the patch.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The "need_cache_flush" variable is never set to false. When the
variable is true that means we print a warning message at the end of
the function.
Fixes: 3418d036c8 ("raid5-ppl: Partial Parity Log write logging implementation")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The 'writes_pending' counter is used to determine when the
array is stable so that it can be marked in the superblock
as "Clean". Consequently it needs to be updated frequently
but only checked for zero occasionally. Recent changes to
raid5 cause the count to be updated even more often - once
per 4K rather than once per bio. This provided
justification for making the updates more efficient.
So we replace the atomic counter a percpu-refcount.
This can be incremented and decremented cheaply most of the
time, and can be switched to "atomic" mode when more
precise counting is needed. As it is possible for multiple
threads to want a precise count, we introduce a
"sync_checker" counter to count the number of threads
in "set_in_sync()", and only switch the refcount back
to percpu mode when that is zero.
We need to be careful about races between set_in_sync()
setting ->in_sync to 1, and md_write_start() setting it
to zero. md_write_start() holds the rcu_read_lock()
while checking if the refcount is in percpu mode. If
it is, then we know a switch to 'atomic' will not happen until
after we call rcu_read_unlock(), in which case set_in_sync()
will see the elevated count, and not set in_sync to 1.
If it is not in percpu mode, we take the mddev->lock to
ensure proper synchronization.
It is no longer possible to quickly check if the count is zero, which
we previously did to update a timer or to schedule the md_thread.
So now we do these every time we decrement that counter, but make
sure they are fast.
mod_timer() already optimizes the case where the timeout value doesn't
actually change. We leverage that further by always rounding off the
jiffies to the timeout value. This may delay the marking of 'clean'
slightly, but ensure we only perform atomic operation here when absolutely
needed.
md_wakeup_thread() current always calls wake_up(), even if
THREAD_WAKEUP is already set. That too can be optimised to avoid
calls to wake_up().
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
If ->in_sync is being set just as md_write_start() is being called,
it is possible that set_in_sync() won't see the elevated
->writes_pending, and md_write_start() won't see the set ->in_sync.
To close this race, re-test ->writes_pending after setting ->in_sync,
and add memory barriers to ensure the increment of ->writes_pending
will be seen by the time of this second test, or the new ->in_sync
will be seen by md_write_start().
Add a spinlock to array_state_show() to ensure this temporary
instability is never visible from userspace.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Three separate places in md.c check if the number of active
writes is zero and, if so, sets mddev->in_sync.
There are a few differences, but there shouldn't be:
- it is always appropriate to notify the change in
sysfs_state, and there is no need to do this outside a
spin-locked region.
- we never need to check ->recovery_cp. The state of resync
is not relevant for whether there are any pending writes
or not (which is what ->in_sync reports).
So create set_in_sync() which does the correct tests and
makes the correct changes, and call this in all three
places.
Any behaviour changes here a minor and cosmetic.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This test on ->writes_pending cannot be safe as the counter
can be incremented at any moment and cannot be locked against.
Change it to test conf->active_stripes, which at least
can be locked against. More changes are still needed.
A future patch will change ->writes_pending, and testing it here will
be very inconvenient.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Change to use bio->__bi_remaining to count number of r1bio attached
to a bio.
See precious raid10 patch for more details.
Like the raid10.c patch, this fixes a bug as nr_queued and nr_pending
used to measure different things, but were being compared.
This patch fixes another bug in that nr_pending previously did not
could write-behind requests, so behind writes could continue while
resync was happening. How that nr_pending counts all r1_bio,
the resync cannot commence until the behind writes have completed.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
raid10 currently repurposes bi_phys_segments on each
incoming bio to count how many r10bio was used to encode the
request.
We need to know when the number of attached r10bio reaches
zero to:
1/ call bio_endio() when all IO on the bio is finished
2/ decrement ->nr_pending so that resync IO can proceed.
Now that the bio has its own __bi_remaining counter, that
can be used instead. We can call bio_inc_remaining to
increment the counter and call bio_endio() every time an
r10bio completes, rather than only when bi_phys_segments
reaches zero.
This addresses point 1, but not point 2. bio_endio()
doesn't (and cannot) report when the last r10bio has
finished, so a different approach is needed.
So: instead of counting bios in ->nr_pending, count r10bios.
i.e. every time we attach a bio, increment nr_pending.
Every time an r10bio completes, decrement nr_pending.
Normally we only increment nr_pending after first checking
that ->barrier is zero, or some other non-trivial tests and
possible waiting. When attaching multiple r10bios to a bio,
we only need the tests and the waiting once. After the
first increment, subsequent increments can happen
unconditionally as they are really all part of the one
request.
So introduce inc_pending() which can be used when we know
that nr_pending is already elevated.
Note that this fixes a bug. freeze_array() contains the line
atomic_read(&conf->nr_pending) == conf->nr_queued+extra,
which implies that the units for ->nr_pending, ->nr_queued and extra
are the same.
->nr_queue and extra count r10_bios, but prior to this patch,
->nr_pending counted bios. If a bio ever resulted in multiple
r10_bios (due to bad blocks), freeze_array() would not work correctly.
Now it does.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When raid1 or raid10 find they will need to allocate a new
r1bio/r10bio, in order to work around a known bad block, they
account for the allocation well before the allocation is
made. This separation makes the correctness less obvious
and requires comments.
The accounting needs to be a little before: before the first
rXbio is submitted, but that is all.
So move the accounting down to where it makes more sense.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This reverts commit e8d7c33232.
Now that raid5 doesn't abuse bi_phys_segments any more, we no longer
need to impose these limits.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When a read request, which bypassed the cache, fails, we need to retry
it through the cache.
This involves attaching it to a sequence of stripe_heads, and it may not
be possible to get all the stripe_heads we need at once.
We do what we can, and record how far we got in ->bi_phys_segments so
we can pick up again later.
There is only ever one bio which may have a non-zero offset stored in
->bi_phys_segments, the one that is either active in the single thread
which calls retry_aligned_read(), or is in conf->retry_read_aligned
waiting for retry_aligned_read() to be called again.
So we only need to store one offset value. This can be in a local
variable passed between remove_bio_from_retry() and
retry_aligned_read(), or in the r5conf structure next to the
->retry_read_aligned pointer.
Storing it there allows the last usage of ->bi_phys_segments to be
removed from md/raid5.c.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
md/raid5 needs to keep track of how many stripe_heads are processing a
bio so that it can delay calling bio_endio() until all stripe_heads
have completed. It currently uses 16 bits of ->bi_phys_segments for
this purpose.
16 bits is only enough for 256M requests, and it is possible for a
single bio to be larger than this, which causes problems. Also, the
bio struct contains a larger counter, __bi_remaining, which has a
purpose very similar to the purpose of our counter. So stop using
->bi_phys_segments, and instead use __bi_remaining.
This means we don't need to initialize the counter, as our caller
initializes it to '1'. It also means we can call bio_endio() directly
as it tests this counter internally.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
We currently gather bios that need to be returned into a bio_list
and call bio_endio() on them all together.
The original reason for this was to avoid making the calls while
holding a spinlock.
Locking has changed a lot since then, and that reason is no longer
valid.
So discard return_io() and various return_bi lists, and just call
bio_endio() directly as needed.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
If a device fails during a write, we must ensure the failure is
recorded in the metadata before the completion of the write is
acknowleged.
Commit c3cce6cda1 ("md/raid5: ensure device failure recorded before
write request returns.") added code for this, but it was
unnecessarily complicated. We already had similar functionality for
handling updates to the bad-block-list, thanks to Commit de393cdea6
("md: make it easier to wait for bad blocks to be acknowledged.")
So revert most of the former commit, and instead avoid collecting
completed writes if MD_CHANGE_PENDING is set. raid5d() will then flush
the metadata and retry the stripe_head.
As this change can leave a stripe_head ready for handling immediately
after handle_active_stripes() returns, we change raid5_do_work() to
pause when MD_CHANGE_PENDING is set, so that it doesn't spin.
We check MD_CHANGE_PENDING *after* analyse_stripe() as it could be set
asynchronously. After analyse_stripe(), we have collected stable data
about the state of devices, which will be used to make decisions.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
We use md_write_start() to increase the count of pending writes, and
md_write_end() to decrement the count. We currently count bios
submitted to md/raid5. Change it count stripe_heads that a WRITE bio
has been attached to.
So now, raid5_make_request() calls md_write_start() and then
md_write_end() to keep the count elevated during the setup of the
request.
add_stripe_bio() calls md_write_start() for each stripe_head, and the
completion routines always call md_write_end(), instead of only
calling it when raid5_dec_bi_active_stripes() returns 0.
make_discard_request also calls md_write_start/end().
The parallel between md_write_{start,end} and use of bi_phys_segments
can be seen in that:
Whenever we set bi_phys_segments to 1, we now call md_write_start.
Whenever we increment it on non-read requests with
raid5_inc_bi_active_stripes(), we now call md_write_start().
Whenever we decrement bi_phys_segments on non-read requsts with
raid5_dec_bi_active_stripes(), we now call md_write_end().
This reduces our dependence on keeping a per-bio count of active
stripes in bi_phys_segments.
md_write_inc() is added which parallels md_write_start(), but requires
that a write has already been started, and is certain never to sleep.
This can be used inside a spinlocked region when adding to a write
request.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The dm_bitset_cursor_begin() call was using the incorrect nr_entries.
Also, the last dm_bitset_cursor_next() must be avoided if we're at the
end of the cursor.
Fixes: 7f1b21591a ("dm cache metadata: use cursor api in blocks_are_clean_separate_dirty()")
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Since we have switched to sync way to handle METADATA_UPDATED
msg for md-cluster, then process_metadata_update is depended
on mddev->thread->wqueue.
With the new change, clustered raid could possible hang if
array received a METADATA_UPDATED msg after array unregistered
mddev->thread, so we need to stop clustered raid (bitmap_destroy
-> bitmap_free -> md_cluster_stop) earlier than unregister
thread (mddev_detach -> md_unregister_thread).
And this change should be safe for non-clustered raid since
all writes are stopped before the destroy. Also in md_run,
we activate the personality (pers->run()) before activating
the bitmap (bitmap_create()). So it is pleasingly symmetric
to stop the bitmap (bitmap_destroy()) before stopping the
personality (__md_stop() calls pers->free()), we achieve this
by move bitmap_destroy to the beginning of __md_stop.
But we don't want to break the codes for waiting behind IO as
Shaohua mentioned, so introduce bitmap_wait_behind_writes to
call the codes, and call the new fun in both mddev_detach and
bitmap_destroy, then we will not break original behind IO code
and also fit the new condition well.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
In r5c_finish_stripe_write_out(), R5LOG_PAYLOAD_FLUSH is append to
log->current_io.
Appending R5LOG_PAYLOAD_FLUSH in quiesce needs extra writes to
journal. To simplify the logic, we just skip R5LOG_PAYLOAD_FLUSH in
quiesce.
Even R5LOG_PAYLOAD_FLUSH supports multiple stripes per payload.
However, current implementation is one stripe per R5LOG_PAYLOAD_FLUSH,
which is simpler.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This patch adds handling of R5LOG_PAYLOAD_FLUSH in journal recovery.
Next patch will add logic that generate R5LOG_PAYLOAD_FLUSH on flush
finish.
When R5LOG_PAYLOAD_FLUSH is seen in recovery, pending data and parity
will be dropped from recovery. This will reduce the number of stripes
to replay, and thus accelerate the recovery process.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Allow writing to 'consistency_policy' attribute when the array is
active. Add a new function 'change_consistency_policy' to the
md_personality operations structure to handle the change in the
personality code. Values "ppl" and "resync" are accepted and
turn PPL on and off respectively.
When enabling PPL its location and size should first be set using
'ppl_sector' and 'ppl_size' attributes and a valid PPL header should be
written at this location on each member device.
Enabling or disabling PPL is performed under a suspended array. The
raid5_reset_stripe_cache function frees the stripe cache and allocates
it again in order to allocate or free the ppl_pages for the stripes in
the stripe cache.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Add a function to modify the log by removing an rdev when a drive fails
or adding when a spare/replacement is activated as a raid member.
Removing a disk just clears the child log rdev pointer. No new stripes
will be accepted for this child log in ppl_write_stripe() and running io
units will be processed without writing PPL to the device.
Adding a disk sets the child log rdev pointer and writes an empty PPL
header.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Load the log from each disk when starting the array and recover if the
array is dirty.
The initial empty PPL is written by mdadm. When loading the log we
verify the header checksum and signature. For external metadata arrays
the signature is verified in userspace, so here we read it from the
header, verifying only if it matches on all disks, and use it later when
writing PPL.
In addition to the header checksum, each header entry also contains a
checksum of its partial parity data. If the header is valid, recovery is
performed for each entry until an invalid entry is found. If the array
is not degraded and recovery using PPL fully succeeds, there is no need
to resync the array because data and parity will be consistent, so in
this case resync will be disabled.
Due to compatibility with IMSM implementations on other systems, we
can't assume that the recovery data block size is always 4K. Writes
generated by MD raid5 don't have this issue, but when recovering PPL
written in other environments it is possible to have entries with
512-byte sector granularity. The recovery code takes this into account
and also the logical sector size of the underlying drives.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Add 'consistency_policy' attribute for array. It indicates how the array
maintains consistency in case of unexpected shutdown.
Add 'ppl_sector' and 'ppl_size' for rdev, which describe the location
and size of the PPL space on the device. They can't be changed for
active members if the array is started and PPL is enabled, so in the
setter functions only basic checks are performed. More checks are done
in ppl_validate_rdev() when starting the log.
These attributes are writable to allow enabling PPL for external
metadata arrays and (later) to enable/disable PPL for a running array.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Implement the calculation of partial parity for a stripe and PPL write
logging functionality. The description of PPL is added to the
documentation. More details can be found in the comments in raid5-ppl.c.
Attach a page for holding the partial parity data to stripe_head.
Allocate it only if mddev has the MD_HAS_PPL flag set.
Partial parity is the xor of not modified data chunks of a stripe and is
calculated as follows:
- reconstruct-write case:
xor data from all not updated disks in a stripe
- read-modify-write case:
xor old data and parity from all updated disks in a stripe
Implement it using the async_tx API and integrate into raid_run_ops().
It must be called when we still have access to old data, so do it when
STRIPE_OP_BIODRAIN is set, but before ops_run_prexor5(). The result is
stored into sh->ppl_page.
Partial parity is not meaningful for full stripe write and is not stored
in the log or used for recovery, so don't attempt to calculate it when
stripe has STRIPE_FULL_WRITE.
Put the PPL metadata structures to md_p.h because userspace tools
(mdadm) will also need to read/write PPL.
Warn about using PPL with enabled disk volatile write-back cache for
now. It can be removed once disk cache flushing before writing PPL is
implemented.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Move raid5-cache declarations from raid5.h to raid5-log.h, add inline
wrappers for functions which will be shared with ppl and use them in
raid5 core instead of direct calls to raid5-cache.
Remove unused parameter from r5c_cache_data(), move two duplicated
pr_debug() calls to r5l_init_log().
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Include information about PPL location and size into mdp_superblock_1
and copy it to/from rdev. Because PPL is mutually exclusive with bitmap,
put it in place of 'bitmap_offset'. Add a new flag MD_FEATURE_PPL for
'feature_map', analogically to MD_FEATURE_BITMAP_OFFSET. Add MD_HAS_PPL
to mddev->flags to indicate that PPL is enabled on an array.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
In r5cache recovery, the journal device is scanned page by page.
Currently, we use sync_page_io() to read journal device. This is
not efficient when we have to recovery many stripes from the journal.
To improve the speed of recovery, this patch introduces a read ahead
page pool (ra_pool) to recovery_ctx. With ra_pool, multiple consecutive
pages are read in one IO. Then the recovery code read the journal from
ra_pool.
With ra_pool, r5l_recovery_ctx has become much bigger. Therefore,
r5l_recovery_log() is refactored so r5l_recovery_ctx is not using
stack space.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Previous patch (raid5: only dispatch IO from raid5d for harddisk raid)
defers IO dispatching. The goal is to create better IO pattern. At that
time, we don't sort the deffered IO and hope the block layer can do IO
merge and sort. Now the raid5-cache writeback could create large amount
of bios. And if we enable muti-thread for stripe handling, we can't
control when to dispatch IO to raid disks. In a lot of time, we are
dispatching IO which block layer can't do merge effectively.
This patch moves further for the IO dispatching defer. We accumulate
bios, but we don't dispatch all the bios after a threshold is met. This
'dispatch partial portion of bios' stragety allows bios coming in a
large time window are sent to disks together. At the dispatching time,
there is large chance the block layer can merge the bios. To make this
more effective, we dispatch IO in ascending order. This increases
request merge chance and reduces disk seek.
Signed-off-by: Shaohua Li <shli@fb.com>
Bump the flush stripe batch size to 2048. For my 12 disks raid
array, the stripes takes:
12 * 4k * 2048 = 96MB
This is still quite small. A hardware raid card generally has 1GB size,
which we suggest the raid5-cache has similar cache size.
The advantage of a big batch size is we can dispatch a lot of IO in the
same time, then we can do some scheduling to make better IO pattern.
Last patch prioritizes stripes, so we don't worry about a big flush
stripe batch will starve normal stripes.
Signed-off-by: Shaohua Li <shli@fb.com>
In raid5-cache writeback mode, we have two types of stripes to handle.
- stripes which aren't cached yet
- stripes which are cached and flushing out to raid disks
Upperlayer is more sensistive to latency of the first type of stripes
generally. But we only one handle list for all these stripes, where the
two types of stripes are mixed together. When reclaim flushes a lot of
stripes, the first type of stripes could be noticeably delayed. On the
other hand, if the log space is tight, we'd like to handle the second
type of stripes faster and free log space.
This patch destinguishes the two types stripes. They are added into
different handle list. When we try to get a stripe to handl, we prefer
the first type of stripes unless log space is tight.
This should have no impact for !writeback case.
Signed-off-by: Shaohua Li <shli@fb.com>
To update size for cluster raid, we need to make
sure all nodes can perform the change successfully.
However, it is possible that some of them can't do
it due to failure (bitmap_resize could fail). So
we need to consider the issue before we set the
capacity unconditionally, and we use below steps
to perform sanity check.
1. A change the size, then broadcast METADATA_UPDATED
msg.
2. B and C receive METADATA_UPDATED change the size
excepts call set_capacity, sync_size is not update
if the change failed. Also call bitmap_update_sb
to sync sb to disk.
3. A checks other node's sync_size, if sync_size has
been updated in all nodes, then send CHANGE_CAPACITY
msg otherwise send msg to revert previous change.
4. B and C call set_capacity if receive CHANGE_CAPACITY
msg, otherwise pers->resize will be called to restore
the old value.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Support resize is a little complex for clustered
raid, since we need to ensure all the nodes share
the same knowledge about the size of raid.
We achieve the goal by check the sync_size which
is in each node's bitmap, we can only change the
capacity after cluster_check_sync_size returns 0.
Also, get_bitmap_from_slot is added to get a slot's
bitmap. And we exported some funcs since they are
used in cluster_check_sync_size().
We can also reuse get_bitmap_from_slot to remove
redundant code existed in bitmap_copy_from_slot.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The msg type CHANGE_CAPACITY is introduced to support
resize clustered raid in later patch, and it is sent
after all the nodes have the same sync_size, receiver
node just need to set new capacity once received this
msg.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Previously, when node received METADATA_UPDATED msg, it just
need to wakeup mddev->thread, then md_reload_sb will be called
eventually.
We taken the asynchronous way to avoid a deadlock issue, the
deadlock issue could happen when one node is receiving the
METADATA_UPDATED msg (wants reconfig_mutex) and trying to run
the path:
md_check_recovery -> mddev_trylock(hold reconfig_mutex)
-> md_update_sb-metadata_update_start
(want EX on token however token is
got by the sending node)
Since we will support resizing for clustered raid, and we
need the metadata update handling to be synchronous so that
the initiating node can detect failure, so we need to change
the way for handling METADATA_UPDATED msg.
But, we obviously need to avoid above deadlock with the
sync way. To make this happen, we considered to not hold
reconfig_mutex to call md_reload_sb, if some other thread
has already taken reconfig_mutex and waiting for the 'token',
then process_recvd_msg() can safely call md_reload_sb()
without taking the mutex. This is because we can be certain
that no other thread will take the mutex, and we also certain
that the actions performed by md_reload_sb() won't interfere
with anything that the other thread is in the middle of.
To make this more concrete, we added a new cinfo->state bit
MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD
Which is set in lock_token() just before dlm_lock_sync() is
called, and cleared just after. As lock_token() is always
called with reconfig_mutex() held (the specific case is the
resync_info_update which is distinguished well in previous
patch), if process_recvd_msg() finds that the new bit is set,
then the mutex must be held by some other thread, and it will
keep waiting.
So process_metadata_update() can call md_reload_sb() if either
mddev_trylock() succeeds, or if MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD
is set. The tricky bit is what to do if neither of these apply.
We need to wait. Fortunately mddev_unlock() always calls wake_up()
on mddev->thread->wqueue. So we can get lock_token() to call
wake_up() on that when it sets the bit.
There are also some related changes inside this commit:
1. remove RELOAD_SB related codes since there are not valid anymore.
2. mddev is added into md_cluster_info then we can get mddev inside
lock_token.
3. add new parameter for lock_token to distinguish reconfig_mutex
is held or not.
And, we need to set MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD in below:
1. set it before unregister thread, otherwise a deadlock could
appear if stop a resyncing array.
This is because md_unregister_thread(&cinfo->recv_thread) is
blocked by recv_daemon -> process_recvd_msg
-> process_metadata_update.
To resolve the issue, MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD is
also need to be set before unregister thread.
2. set it in metadata_update_start to fix another deadlock.
a. Node A sends METADATA_UPDATED msg (held Token lock).
b. Node B wants to do resync, and is blocked since it can't
get Token lock, but MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD is
not set since the callchain
(md_do_sync -> sync_request
-> resync_info_update
-> sendmsg
-> lock_comm -> lock_token)
doesn't hold reconfig_mutex.
c. Node B trys to update sb (held reconfig_mutex), but stopped
at wait_event() in metadata_update_start since we have set
MD_CLUSTER_SEND_LOCK flag in lock_comm (step 2).
d. Then Node B receives METADATA_UPDATED msg from A, of course
recv_daemon is blocked forever.
Since metadata_update_start always calls lock_token with reconfig_mutex,
we need to set MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD here as well, and
lock_token don't need to set it twice unless lock_token is invoked from
lock_comm.
Finally, thanks to Neil for his great idea and help!
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Pull MD fixes from Shaohua Li:
- fix a parity calculation bug of raid5 cache by Song
- fix a potential deadlock issue by me
- fix two endian issues by Jason
- fix a disk limitation issue by Neil
- other small fixes and cleanup
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
md/raid1: fix a trivial typo in comments
md/r5cache: fix set_syndrome_sources() for data in cache
md: fix incorrect use of lexx_to_cpu in does_sb_need_changing
md: fix super_offset endianness in super_1_rdev_size_change
md/raid1/10: fix potential deadlock
md: don't impose the MD_SB_DISKS limit on arrays without metadata.
md: move funcs from pers->resize to update_size
md-cluster: remove useless memset from gather_all_resync_info
md-cluster: free md_cluster_info if node leave cluster
md: delete dead code
md/raid10: submit bio directly to replacement disk
If the hash tree itself is sufficiently corrupt in addition to data blocks,
it's possible for error correction to end up in a deep recursive loop,
which eventually causes a kernel panic. This change limits the
recursion to a reasonable level during a single I/O operation.
Fixes: a739ff3f54 ("dm verity: add support for forward error correction")
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # v4.5+
raid1.c: fix a trivial typo in comments of freeze_array().
Cc: Jack Wang <jack.wang.usish@gmail.com>
Cc: Guoqing Jiang <gqjiang@suse.com>
Cc: John Stoffel <john@stoffel.org>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Zhilong Liu <zlliu@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Before this patch, device InJournal will be included in prexor
(SYNDROME_SRC_WANT_DRAIN) but not in reconstruct (SYNDROME_SRC_WRITTEN). So it
will break parity calculation. With srctype == SYNDROME_SRC_WRITTEN, we need
include both dev with non-null ->written and dev with R5_InJournal. This fixes
logic in 1e6d690(md/r5cache: caching phase of r5cache)
Cc: stable@vger.kernel.org (v4.10+)
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
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>
The sb->super_offset should be big-endian, but the rdev->sb_start is in
host byte order, so fix this by adding cpu_to_le64.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Neil Brown pointed out a potential deadlock in raid 10 code with
bio_split/chain. The raid1 code could have the same issue, but recent
barrier rework makes it less likely to happen. The deadlock happens in
below sequence:
1. generic_make_request(bio), this will set current->bio_list
2. raid10_make_request will split bio to bio1 and bio2
3. __make_request(bio1), wait_barrer, add underlayer disk bio to
current->bio_list
4. __make_request(bio2), wait_barrer
If raise_barrier happens between 3 & 4, since wait_barrier runs at 3,
raise_barrier waits for IO completion from 3. And since raise_barrier
sets barrier, 4 waits for raise_barrier. But IO from 3 can't be
dispatched because raid10_make_request() doesn't finished yet.
The solution is to adjust the IO ordering. Quotes from Neil:
"
It is much safer to:
if (need to split) {
split = bio_split(bio, ...)
bio_chain(...)
make_request_fn(split);
generic_make_request(bio);
} else
make_request_fn(mddev, bio);
This way we first process the initial section of the bio (in 'split')
which will queue some requests to the underlying devices. These
requests will be queued in generic_make_request.
Then we queue the remainder of the bio, which will be added to the end
of the generic_make_request queue.
Then we return.
generic_make_request() will pop the lower-level device requests off the
queue and handle them first. Then it will process the remainder
of the original bio once the first section has been fully processed.
"
Note, this only happens in read path. In write path, the bio is flushed to
underlaying disks either by blk flush (from schedule) or offladed to raid1/10d.
It's queued in current->bio_list.
Cc: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org (v3.14+, only the raid10 part)
Suggested-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Shaohua Li <shli@fb.com>
These arrays, created with "mdadm --build" don't benefit from a limit.
The default will be used, which is '0' and is interpreted as "don't
impose a limit".
Reported-by: ian_bruce@mail.ru
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
raid1_resize and raid5_resize should also check the
mddev->queue if run underneath dm-raid.
And both set_capacity and revalidate_disk are used in
pers->resize such as raid1, raid10 and raid5. So
move them from personality file to common code.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This memset is not needed. The lvb is already zeroed because
it was recently allocated by lockres_init, which uses kzalloc(),
and read_resync_info() doesn't need it to be zero anyway.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
To avoid memory leak, we need to free the cinfo which
is allocated when node join cluster.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Commit 57c67df(md/raid10: submit IO from originating thread instead of
md thread) submits bio directly for normal disks but not for replacement
disks. There is no point we shouldn't do this for replacement disks.
Cc: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Introduce dm_bufio_set_sector_offset() interface to allow setting a
sector offset for a dm-bufio client. This is a prereq for the DM
integrity target.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add DM_TARGET_INTEGRITY flag that specifies bio integrity metadata is
not inherited but implemented in the target itself.
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The cache policy interfaces have been updated to work well with the new
bio-prison v2 interface's ability to queue work immediately (promotion,
demotion, etc) -- overriding benefit being reduced latency on processing
IO through the cache. Previously such work would be left for the DM
cache core to queue on various lists and then process in batches later
-- this caused a serious delay in latency for IO driven by the cache.
The background tracker code was factored out so that all cache policies
can make use of it.
Also, the "cleaner" policy has been removed and is now a variant of the
smq policy that simply disallows migrations.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The deferred set is gone and all methods have _v2 appended to the end of
their names to allow for continued use of the original bio prison in DM
thin-provisioning.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull sched.h split-up from Ingo Molnar:
"The point of these changes is to significantly reduce the
<linux/sched.h> header footprint, to speed up the kernel build and to
have a cleaner header structure.
After these changes the new <linux/sched.h>'s typical preprocessed
size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
lines), which is around 40% faster to build on typical configs.
Not much changed from the last version (-v2) posted three weeks ago: I
eliminated quirks, backmerged fixes plus I rebased it to an upstream
SHA1 from yesterday that includes most changes queued up in -next plus
all sched.h changes that were pending from Andrew.
I've re-tested the series both on x86 and on cross-arch defconfigs,
and did a bisectability test at a number of random points.
I tried to test as many build configurations as possible, but some
build breakage is probably still left - but it should be mostly
limited to architectures that have no cross-compiler binaries
available on kernel.org, and non-default configurations"
* 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
sched/headers: Clean up <linux/sched.h>
sched/headers: Remove #ifdefs from <linux/sched.h>
sched/headers: Remove the <linux/topology.h> include from <linux/sched.h>
sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h>
sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h>
sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h>
sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/init.h>
sched/core: Remove unused prefetch_stack()
sched/headers: Remove <linux/rculist.h> from <linux/sched.h>
sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h>
sched/headers: Remove <linux/signal.h> from <linux/sched.h>
sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
sched/headers: Remove the runqueue_is_locked() prototype
sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h>
sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h>
sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h>
...
reshape via lvm2; and an additional small patch ontop to bump version
of the dm-raid target outside of the stable@ fix
- A dm-raid fix for a 'dm-4.11-changes' regression introduced by a
commit that was meant to only cleanup confusing branching.
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Merge tag 'dm-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- a dm-raid stable@ fix for possible corruption when triggering a raid
reshape via lvm2; and an additional small patch ontop to bump version
of the dm-raid target outside of the stable@ fix
- a dm-raid fix for a 'dm-4.11-changes' regression introduced by a
commit that was meant to only cleanup confusing branching.
* tag 'dm-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm raid: bump the target version
dm raid: fix data corruption on reshape request
dm raid: fix raid "check" regression due to improper cleanup in raid_message()
But first update usage sites with the new header dependency.
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>
We don't actually need the full rculist.h header in sched.h anymore,
we will be able to include the smaller rcupdate.h header instead.
But first update code that relied on the implicit header inclusion.
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>
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
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>
Update the .c files that depend on these APIs.
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>
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>
We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
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>
We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which
will have to be picked up from other headers and .c files.
Create a trivial placeholder <linux/sched/clock.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
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>
rcu_dereference_key() and user_key_payload() are currently being used in
two different, incompatible ways:
(1) As a wrapper to rcu_dereference() - when only the RCU read lock used
to protect the key.
(2) As a wrapper to rcu_dereference_protected() - when the key semaphor is
used to protect the key and the may be being modified.
Fix this by splitting both of the key wrappers to produce:
(1) RCU accessors for keys when caller has the key semaphore locked:
dereference_key_locked()
user_key_payload_locked()
(2) RCU accessors for keys when caller holds the RCU read lock:
dereference_key_rcu()
user_key_payload_rcu()
This should fix following warning in the NFS idmapper
===============================
[ INFO: suspicious RCU usage. ]
4.10.0 #1 Tainted: G W
-------------------------------
./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 0
1 lock held by mount.nfs/5987:
#0: (rcu_read_lock){......}, at: [<d000000002527abc>] nfs_idmap_get_key+0x15c/0x420 [nfsv4]
stack backtrace:
CPU: 1 PID: 5987 Comm: mount.nfs Tainted: G W 4.10.0 #1
Call Trace:
dump_stack+0xe8/0x154 (unreliable)
lockdep_rcu_suspicious+0x140/0x190
nfs_idmap_get_key+0x380/0x420 [nfsv4]
nfs_map_name_to_uid+0x2a0/0x3b0 [nfsv4]
decode_getfattr_attrs+0xfac/0x16b0 [nfsv4]
decode_getfattr_generic.constprop.106+0xbc/0x150 [nfsv4]
nfs4_xdr_dec_lookup_root+0xac/0xb0 [nfsv4]
rpcauth_unwrap_resp+0xe8/0x140 [sunrpc]
call_decode+0x29c/0x910 [sunrpc]
__rpc_execute+0x140/0x8f0 [sunrpc]
rpc_run_task+0x170/0x200 [sunrpc]
nfs4_call_sync_sequence+0x68/0xa0 [nfsv4]
_nfs4_lookup_root.isra.44+0xd0/0xf0 [nfsv4]
nfs4_lookup_root+0xe0/0x350 [nfsv4]
nfs4_lookup_root_sec+0x70/0xa0 [nfsv4]
nfs4_find_root_sec+0xc4/0x100 [nfsv4]
nfs4_proc_get_rootfh+0x5c/0xf0 [nfsv4]
nfs4_get_rootfh+0x6c/0x190 [nfsv4]
nfs4_server_common_setup+0xc4/0x260 [nfsv4]
nfs4_create_server+0x278/0x3c0 [nfsv4]
nfs4_remote_mount+0x50/0xb0 [nfsv4]
mount_fs+0x74/0x210
vfs_kern_mount+0x78/0x220
nfs_do_root_mount+0xb0/0x140 [nfsv4]
nfs4_try_mount+0x60/0x100 [nfsv4]
nfs_fs_mount+0x5ec/0xda0 [nfs]
mount_fs+0x74/0x210
vfs_kern_mount+0x78/0x220
do_mount+0x254/0xf70
SyS_mount+0x94/0x100
system_call+0x38/0xe0
Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
This version bump reflects that the reshape corruption fix (commit
92a39f6cc "dm raid: fix data corruption on reshape request") is
present.
Done as a separate fix because the above referenced commit is marked for
stable and target version bumps in a stable@ fix are a recipe for the
fix to never get backported to stable@ kernels (because of target
version number conflicts).
Also, move RESUME_STAY_FROZEN_FLAGS up with the reset the the _FLAGS
definitions now that we don't need to worry about stable@ conflicts as a
result of missing context.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The lvm2 sequence to manage dm-raid constructor flags that trigger a
rebuild or a reshape is defined as:
1) load table with flags (e.g. rebuild/delta_disks/data_offset)
2) clear out the flags in lvm2 metadata
3) store the lvm2 metadata, reload the table to reset the flags
previously established during the initial load (1) -- in order to
prevent repeatedly requesting a rebuild or a reshape on activation
Currently, loading an inactive table with rebuild/reshape flags
specified will cause dm-raid to rebuild/reshape on resume and thus start
updating the raid metadata (about the progress). When the second table
reload, to reset the flags, occurs the constructor accesses the volatile
progress state kept in the raid superblocks. Because the active mapping
is still processing the rebuild/reshape, that position will be stale by
the time the device is resumed.
In the reshape case, this causes data corruption by processing already
reshaped stripes again. In the rebuild case, it does _not_ cause data
corruption but instead involves superfluous rebuilds.
Fix by keeping the raid set frozen during the first resume and then
allow the rebuild/reshape during the second resume.
Fixes: 9dbd1aa3a ("dm raid: add reshaping support to the target")
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 4.8+
While cleaning up awkward branching in raid_message() a raid set "check"
regression was introduced because "check" needs both MD_RECOVERY_SYNC
and MD_RECOVERY_REQUESTED flags set.
Fix this regression by explicitly setting both flags for the "check"
case (like is also done for the "repair" case, but redundant set_bit()s
are perfectly fine because it adds clarity to what is needed in response
to both messages -- in addition this isn't fast path code).
Fixes: 105db59912 ("dm raid: cleanup awkward branching in raid_message() option processing")
Reported-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull md updates from Shaohua Li:
"Mainly fixes bugs and improves performance:
- Improve scalability for raid1 from Coly
- Improve raid5-cache read performance, disk efficiency and IO
pattern from Song and me
- Fix a race condition of disk hotplug for linear from Coly
- A few cleanup patches from Ming and Byungchul
- Fix a memory leak from Neil
- Fix WRITE SAME IO failure from me
- Add doc for raid5-cache from me"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: (23 commits)
md/raid1: fix write behind issues introduced by bio_clone_bioset_partial
md/raid1: handle flush request correctly
md/linear: shutup lockdep warnning
md/raid1: fix a use-after-free bug
RAID1: avoid unnecessary spin locks in I/O barrier code
RAID1: a new I/O barrier implementation to remove resync window
md/raid5: Don't reinvent the wheel but use existing llist API
md: fast clone bio in bio_clone_mddev()
md: remove unnecessary check on mddev
md/raid1: use bio_clone_bioset_partial() in case of write behind
md: fail if mddev->bio_set can't be created
block: introduce bio_clone_bioset_partial()
md: disable WRITE SAME if it fails in underlayer disks
md/raid5-cache: exclude reclaiming stripes in reclaim check
md/raid5-cache: stripe reclaim only counts valid stripes
MD: add doc for raid5-cache
Documentation: move MD related doc into a separate dir
md: ensure md devices are freed before module is unloaded.
md/r5cache: improve journal device efficiency
md/r5cache: enable chunk_aligned_read with write back cache
...
Pull block updates and fixes from Jens Axboe:
- NVMe updates and fixes that missed the first pull request. This
includes bug fixes, and support for autonomous power management.
- Fix from Christoph for missing clear of the request payload, causing
a problem with (at least) the storvsc driver.
- Further fixes for the queue/bdi life time issues from Jan.
- The Kconfig mq scheduler update from me.
- Fixing a use-after-free in dm-rq, spotted by Bart, introduced in this
merge window.
- Three fixes for nbd from Josef.
- Bug fix from Omar, fixing a bug in sas transport code that oopses
when bsg ioctls were used. From Omar.
- Improvements to the queue restart and tag wait from from Omar.
- Set of fixes for the sed/opal code from Scott.
- Three trivial patches to cciss from Tobin
* 'for-linus' of git://git.kernel.dk/linux-block: (41 commits)
dm-rq: don't dereference request payload after ending request
blk-mq-sched: separate mark hctx and queue restart operations
blk-mq: use sbq wait queues instead of restart for driver tags
block/sed-opal: Propagate original error message to userland.
nvme/pci: re-check security protocol support after reset
block/sed-opal: Introduce free_opal_dev to free the structure and clean up state
nvme: detect NVMe controller in recent MacBooks
nvme-rdma: add support for host_traddr
nvmet-rdma: Fix error handling
nvmet-rdma: use nvme cm status helper
nvme-rdma: move nvme cm status helper to .h file
nvme-fc: don't bother to validate ioccsz and iorcsz
nvme/pci: No special case for queue busy on IO
nvme/core: Fix race kicking freed request_queue
nvme/pci: Disable on removal when disconnected
nvme: Enable autonomous power state transitions
nvme: Add a quirk mechanism that uses identify_ctrl
nvme: make nvmf_register_transport require a create_ctrl callback
nvme: Use CNS as 8-bit field and avoid endianness conversion
nvme: add semicolon in nvme_command setting
...
Bart reported a case where dm would crash with use-after-free
poison. This is due to dm_softirq_done() accessing memory
associated with a request after calling end_request on it.
This is most visible on !blk-mq, since we free the memory
immediately for that case.
Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: eb8db831be ("dm: always defer request allocation to the owner of the request_queue")
Signed-off-by: Jens Axboe <axboe@fb.com>
There are two issues, introduced by commit 8e58e32(md/raid1: use
bio_clone_bioset_partial() in case of write behind):
- bio_clone_bioset_partial() uses bytes instead of sectors as parameters
- in writebehind mode, we return bio if all !writemostly disk bios finish,
which could happen before writemostly disk bios run. So all
writemostly disk bios should have their bvec. Here we just make sure
all bios are cloned instead of fast cloned.
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
I got a warning triggered in align_to_barrier_unit_end. It's a flush
request so sectors == 0. The flush request happens to work well without
the new barrier patch, but we'd better handle it explictly.
Cc: NeilBrown <neilb@suse.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Commit 03a9e24(md linear: fix a race between linear_add() and
linear_congested()) introduces the warnning.
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
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
...
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Merge tag 'for-4.11/linus-merge-signed' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
- blk-mq scheduling framework from me and Omar, with a port of the
deadline scheduler for this framework. A port of BFQ from Paolo is in
the works, and should be ready for 4.12.
- Various fixups and improvements to the above scheduling framework
from Omar, Paolo, Bart, me, others.
- Cleanup of the exported sysfs blk-mq data into debugfs, from Omar.
This allows us to export more information that helps debug hangs or
performance issues, without cluttering or abusing the sysfs API.
- Fixes for the sbitmap code, the scalable bitmap code that was
migrated from blk-mq, from Omar.
- Removal of the BLOCK_PC support in struct request, and refactoring of
carrying SCSI payloads in the block layer. This cleans up the code
nicely, and enables us to kill the SCSI specific parts of struct
request, shrinking it down nicely. From Christoph mainly, with help
from Hannes.
- Support for ranged discard requests and discard merging, also from
Christoph.
- Support for OPAL in the block layer, and for NVMe as well. Mainly
from Scott Bauer, with fixes/updates from various others folks.
- Error code fixup for gdrom from Christophe.
- cciss pci irq allocation cleanup from Christoph.
- Making the cdrom device operations read only, from Kees Cook.
- Fixes for duplicate bdi registrations and bdi/queue life time
problems from Jan and Dan.
- Set of fixes and updates for lightnvm, from Matias and Javier.
- A few fixes for nbd from Josef, using idr to name devices and a
workqueue deadlock fix on receive. Also marks Josef as the current
maintainer of nbd.
- Fix from Josef, overwriting queue settings when the number of
hardware queues is updated for a blk-mq device.
- NVMe fix from Keith, ensuring that we don't repeatedly mark and IO
aborted, if we didn't end up aborting it.
- SG gap merging fix from Ming Lei for block.
- Loop fix also from Ming, fixing a race and crash between setting loop
status and IO.
- Two block race fixes from Tahsin, fixing request list iteration and
fixing a race between device registration and udev device add
notifiations.
- Double free fix from cgroup writeback, from Tejun.
- Another double free fix in blkcg, from Hou Tao.
- Partition overflow fix for EFI from Alden Tondettar.
* tag 'for-4.11/linus-merge-signed' of git://git.kernel.dk/linux-block: (156 commits)
nvme: Check for Security send/recv support before issuing commands.
block/sed-opal: allocate struct opal_dev dynamically
block/sed-opal: tone down not supported warnings
block: don't defer flushes on blk-mq + scheduling
blk-mq-sched: ask scheduler for work, if we failed dispatching leftovers
blk-mq: don't special case flush inserts for blk-mq-sched
blk-mq-sched: don't add flushes to the head of requeue queue
blk-mq: have blk_mq_dispatch_rq_list() return if we queued IO or not
block: do not allow updates through sysfs until registration completes
lightnvm: set default lun range when no luns are specified
lightnvm: fix off-by-one error on target initialization
Maintainers: Modify SED list from nvme to block
Move stack parameters for sed_ioctl to prevent oversized stack with CONFIG_KASAN
uapi: sed-opal fix IOW for activate lsp to use correct struct
cdrom: Make device operations read-only
elevator: fix loading wrong elevator type for blk-mq devices
cciss: switch to pci_irq_alloc_vectors
block/loop: fix race between I/O and set_status
blk-mq-sched: don't hold queue_lock when calling exit_icq
block: set make_request_fn manually in blk_mq_update_nr_hw_queues
...
Pull locking updates from Ingo Molnar:
"The main changes in this cycle were:
- Implement wraparound-safe refcount_t and kref_t types based on
generic atomic primitives (Peter Zijlstra)
- Improve and fix the ww_mutex code (Nicolai Hähnle)
- Add self-tests to the ww_mutex code (Chris Wilson)
- Optimize percpu-rwsems with the 'rcuwait' mechanism (Davidlohr
Bueso)
- Micro-optimize the current-task logic all around the core kernel
(Davidlohr Bueso)
- Tidy up after recent optimizations: remove stale code and APIs,
clean up the code (Waiman Long)
- ... plus misc fixes, updates and cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
fork: Fix task_struct alignment
locking/spinlock/debug: Remove spinlock lockup detection code
lockdep: Fix incorrect condition to print bug msgs for MAX_LOCKDEP_CHAIN_HLOCKS
lkdtm: Convert to refcount_t testing
kref: Implement 'struct kref' using refcount_t
refcount_t: Introduce a special purpose refcount type
sched/wake_q: Clarify queue reinit comment
sched/wait, rcuwait: Fix typo in comment
locking/mutex: Fix lockdep_assert_held() fail
locking/rtmutex: Flip unlikely() branch to likely() in __rt_mutex_slowlock()
locking/rwsem: Reinit wake_q after use
locking/rwsem: Remove unnecessary atomic_long_t casts
jump_labels: Move header guard #endif down where it belongs
locking/atomic, kref: Implement kref_put_lock()
locking/ww_mutex: Turn off __must_check for now
locking/atomic, kref: Avoid more abuse
locking/atomic, kref: Use kref_get_unless_zero() more
locking/atomic, kref: Kill kref_sub()
locking/atomic, kref: Add kref_read()
locking/atomic, kref: Add KREF_INIT()
...
Commit fd76863 (RAID1: a new I/O barrier implementation to remove resync
window) introduces a user-after-free bug.
Signed-off-by: Shaohua Li <shli@fb.com>
When I run a parallel reading performan testing on a md raid1 device with
two NVMe SSDs, I observe very bad throughput in supprise: by fio with 64KB
block size, 40 seq read I/O jobs, 128 iodepth, overall throughput is
only 2.7GB/s, this is around 50% of the idea performance number.
The perf reports locking contention happens at allow_barrier() and
wait_barrier() code,
- 41.41% fio [kernel.kallsyms] [k] _raw_spin_lock_irqsave
- _raw_spin_lock_irqsave
+ 89.92% allow_barrier
+ 9.34% __wake_up
- 37.30% fio [kernel.kallsyms] [k] _raw_spin_lock_irq
- _raw_spin_lock_irq
- 100.00% wait_barrier
The reason is, in these I/O barrier related functions,
- raise_barrier()
- lower_barrier()
- wait_barrier()
- allow_barrier()
They always hold conf->resync_lock firstly, even there are only regular
reading I/Os and no resync I/O at all. This is a huge performance penalty.
The solution is a lockless-like algorithm in I/O barrier code, and only
holding conf->resync_lock when it has to.
The original idea is from Hannes Reinecke, and Neil Brown provides
comments to improve it. I continue to work on it, and make the patch into
current form.
In the new simpler raid1 I/O barrier implementation, there are two
wait barrier functions,
- wait_barrier()
Which calls _wait_barrier(), is used for regular write I/O. If there is
resync I/O happening on the same I/O barrier bucket, or the whole
array is frozen, task will wait until no barrier on same barrier bucket,
or the whold array is unfreezed.
- wait_read_barrier()
Since regular read I/O won't interfere with resync I/O (read_balance()
will make sure only uptodate data will be read out), it is unnecessary
to wait for barrier in regular read I/Os, waiting in only necessary
when the whole array is frozen.
The operations on conf->nr_pending[idx], conf->nr_waiting[idx], conf->
barrier[idx] are very carefully designed in raise_barrier(),
lower_barrier(), _wait_barrier() and wait_read_barrier(), in order to
avoid unnecessary spin locks in these functions. Once conf->
nr_pengding[idx] is increased, a resync I/O with same barrier bucket index
has to wait in raise_barrier(). Then in _wait_barrier() if no barrier
raised in same barrier bucket index and array is not frozen, the regular
I/O doesn't need to hold conf->resync_lock, it can just increase
conf->nr_pending[idx], and return to its caller. wait_read_barrier() is
very similar to _wait_barrier(), the only difference is it only waits when
array is frozen. For heavy parallel reading I/Os, the lockless I/O barrier
code almostly gets rid of all spin lock cost.
This patch significantly improves raid1 reading peroformance. From my
testing, a raid1 device built by two NVMe SSD, runs fio with 64KB
blocksize, 40 seq read I/O jobs, 128 iodepth, overall throughput
increases from 2.7GB/s to 4.6GB/s (+70%).
Changelog
V4:
- Change conf->nr_queued[] to atomic_t.
- Define BARRIER_BUCKETS_NR_BITS by (PAGE_SHIFT - ilog2(sizeof(atomic_t)))
V3:
- Add smp_mb__after_atomic() as Shaohua and Neil suggested.
- Change conf->nr_queued[] from atomic_t to int.
- Change conf->array_frozen from atomic_t back to int, and use
READ_ONCE(conf->array_frozen) to check value of conf->array_frozen
in _wait_barrier() and wait_read_barrier().
- In _wait_barrier() and wait_read_barrier(), add a call to
wake_up(&conf->wait_barrier) after atomic_dec(&conf->nr_pending[idx]),
to fix a deadlock between _wait_barrier()/wait_read_barrier and
freeze_array().
V2:
- Remove a spin_lock/unlock pair in raid1d().
- Add more code comments to explain why there is no racy when checking two
atomic_t variables at same time.
V1:
- Original RFC patch for comments.
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Shaohua Li <shli@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Guoqing Jiang <gqjiang@suse.com>
Reviewed-by: Neil Brown <neilb@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
'Commit 79ef3a8aa1 ("raid1: Rewrite the implementation of iobarrier.")'
introduces a sliding resync window for raid1 I/O barrier, this idea limits
I/O barriers to happen only inside a slidingresync window, for regular
I/Os out of this resync window they don't need to wait for barrier any
more. On large raid1 device, it helps a lot to improve parallel writing
I/O throughput when there are background resync I/Os performing at
same time.
The idea of sliding resync widow is awesome, but code complexity is a
challenge. Sliding resync window requires several variables to work
collectively, this is complexed and very hard to make it work correctly.
Just grep "Fixes: 79ef3a8aa1" in kernel git log, there are 8 more patches
to fix the original resync window patch. This is not the end, any further
related modification may easily introduce more regreassion.
Therefore I decide to implement a much simpler raid1 I/O barrier, by
removing resync window code, I believe life will be much easier.
The brief idea of the simpler barrier is,
- Do not maintain a global unique resync window
- Use multiple hash buckets to reduce I/O barrier conflicts, regular
I/O only has to wait for a resync I/O when both them have same barrier
bucket index, vice versa.
- I/O barrier can be reduced to an acceptable number if there are enough
barrier buckets
Here I explain how the barrier buckets are designed,
- BARRIER_UNIT_SECTOR_SIZE
The whole LBA address space of a raid1 device is divided into multiple
barrier units, by the size of BARRIER_UNIT_SECTOR_SIZE.
Bio requests won't go across border of barrier unit size, that means
maximum bio size is BARRIER_UNIT_SECTOR_SIZE<<9 (64MB) in bytes.
For random I/O 64MB is large enough for both read and write requests,
for sequential I/O considering underlying block layer may merge them
into larger requests, 64MB is still good enough.
Neil also points out that for resync operation, "we want the resync to
move from region to region fairly quickly so that the slowness caused
by having to synchronize with the resync is averaged out over a fairly
small time frame". For full speed resync, 64MB should take less then 1
second. When resync is competing with other I/O, it could take up a few
minutes. Therefore 64MB size is fairly good range for resync.
- BARRIER_BUCKETS_NR
There are BARRIER_BUCKETS_NR buckets in total, which is defined by,
#define BARRIER_BUCKETS_NR_BITS (PAGE_SHIFT - 2)
#define BARRIER_BUCKETS_NR (1<<BARRIER_BUCKETS_NR_BITS)
this patch makes the bellowed members of struct r1conf from integer
to array of integers,
- int nr_pending;
- int nr_waiting;
- int nr_queued;
- int barrier;
+ int *nr_pending;
+ int *nr_waiting;
+ int *nr_queued;
+ int *barrier;
number of the array elements is defined as BARRIER_BUCKETS_NR. For 4KB
kernel space page size, (PAGE_SHIFT - 2) indecates there are 1024 I/O
barrier buckets, and each array of integers occupies single memory page.
1024 means for a request which is smaller than the I/O barrier unit size
has ~0.1% chance to wait for resync to pause, which is quite a small
enough fraction. Also requesting single memory page is more friendly to
kernel page allocator than larger memory size.
- I/O barrier bucket is indexed by bio start sector
If multiple I/O requests hit different I/O barrier units, they only need
to compete I/O barrier with other I/Os which hit the same I/O barrier
bucket index with each other. The index of a barrier bucket which a
bio should look for is calculated by sector_to_idx() which is defined
in raid1.h as an inline function,
static inline int sector_to_idx(sector_t sector)
{
return hash_long(sector >> BARRIER_UNIT_SECTOR_BITS,
BARRIER_BUCKETS_NR_BITS);
}
Here sector_nr is the start sector number of a bio.
- Single bio won't go across boundary of a I/O barrier unit
If a request goes across boundary of barrier unit, it will be split. A
bio may be split in raid1_make_request() or raid1_sync_request(), if
sectors returned by align_to_barrier_unit_end() is smaller than
original bio size.
Comparing to single sliding resync window,
- Currently resync I/O grows linearly, therefore regular and resync I/O
will conflict within a single barrier units. So the I/O behavior is
similar to single sliding resync window.
- But a barrier unit bucket is shared by all barrier units with identical
barrier uinit index, the probability of conflict might be higher
than single sliding resync window, in condition that writing I/Os
always hit barrier units which have identical barrier bucket indexs with
the resync I/Os. This is a very rare condition in real I/O work loads,
I cannot imagine how it could happen in practice.
- Therefore we can achieve a good enough low conflict rate with much
simpler barrier algorithm and implementation.
There are two changes should be noticed,
- In raid1d(), I change the code to decrease conf->nr_pending[idx] into
single loop, it looks like this,
spin_lock_irqsave(&conf->device_lock, flags);
conf->nr_queued[idx]--;
spin_unlock_irqrestore(&conf->device_lock, flags);
This change generates more spin lock operations, but in next patch of
this patch set, it will be replaced by a single line code,
atomic_dec(&conf->nr_queueud[idx]);
So we don't need to worry about spin lock cost here.
- Mainline raid1 code split original raid1_make_request() into
raid1_read_request() and raid1_write_request(). If the original bio
goes across an I/O barrier unit size, this bio will be split before
calling raid1_read_request() or raid1_write_request(), this change
the code logic more simple and clear.
- In this patch wait_barrier() is moved from raid1_make_request() to
raid1_write_request(). In raid_read_request(), original wait_barrier()
is replaced by raid1_read_request().
The differnece is wait_read_barrier() only waits if array is frozen,
using different barrier function in different code path makes the code
more clean and easy to read.
Changelog
V4:
- Add alloc_r1bio() to remove redundant r1bio memory allocation code.
- Fix many typos in patch comments.
- Use (PAGE_SHIFT - ilog2(sizeof(int))) to define BARRIER_BUCKETS_NR_BITS.
V3:
- Rebase the patch against latest upstream kernel code.
- Many fixes by review comments from Neil,
- Back to use pointers to replace arraries in struct r1conf
- Remove total_barriers from struct r1conf
- Add more patch comments to explain how/why the values of
BARRIER_UNIT_SECTOR_SIZE and BARRIER_BUCKETS_NR are decided.
- Use get_unqueued_pending() to replace get_all_pendings() and
get_all_queued()
- Increase bucket number from 512 to 1024
- Change code comments format by review from Shaohua.
V2:
- Use bio_split() to split the orignal bio if it goes across barrier unit
bounday, to make the code more simple, by suggestion from Shaohua and
Neil.
- Use hash_long() to replace original linear hash, to avoid a possible
confilict between resync I/O and sequential write I/O, by suggestion from
Shaohua.
- Add conf->total_barriers to record barrier depth, which is used to
control number of parallel sync I/O barriers, by suggestion from Shaohua.
- In V1 patch the bellowed barrier buckets related members in r1conf are
allocated in memory page. To make the code more simple, V2 patch moves
the memory space into struct r1conf, like this,
- int nr_pending;
- int nr_waiting;
- int nr_queued;
- int barrier;
+ int nr_pending[BARRIER_BUCKETS_NR];
+ int nr_waiting[BARRIER_BUCKETS_NR];
+ int nr_queued[BARRIER_BUCKETS_NR];
+ int barrier[BARRIER_BUCKETS_NR];
This change is by the suggestion from Shaohua.
- Remove some inrelavent code comments, by suggestion from Guoqing.
- Add a missing wait_barrier() before jumping to retry_write, in
raid1_make_write_request().
V1:
- Original RFC patch for comments
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Guoqing Jiang <gqjiang@suse.com>
Reviewed-by: Neil Brown <neilb@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
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>
The sloppy nature of lockless access to percpu pointers
(s->current_path) in rr_select_path(), from multiple threads, is
causing some paths to used more than others -- which results in less
IO performance being observed.
Revert these upstream commits to restore truly symmetric round-robin
IO submission in DM multipath:
b0b477c dm round robin: use percpu 'repeat_count' and 'current_path'
802934b dm round robin: do not use this_cpu_ptr() without having preemption disabled
There is no benefit to all this complexity if repeat_count = 1 (which is
the recommended default).
Cc: stable@vger.kernel.org # 4.6+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Although llist provides proper APIs, they are not used. Make them used.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Declare dm_space_map structures as const as they are only passed as an
argument to the function memcpy. This argument is of type const void *,
so dm_space_map structures having this property can be declared as
const.
File size before:
text data bss dec hex filename
4889 240 0 5129 1409 dm-space-map-metadata.o
File size after:
text data bss dec hex filename
5139 0 0 5139 1413 dm-space-map-metadata.o
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Improves __load_mapping_v1() and __load_mapping_v2() DMERR messages to
explicitly name the cache block number whose mapping couldn't be
loaded.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If "metadata2" is provided as a table argument when creating/loading a
cache target a more compact metadata format, with separate dirty bits,
is used. "metadata2" improves speed of shutting down a cache target.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm_btree_del() is called from an ioctl so don't recurse into FS.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The metadata_space_map_root passed to sm_ll_open_metadata() may or may
not be arch aligned, use memcpy to ensure it is. This is not a fast
path so the extra memcpy doesn't hurt us.
Long-term it'd be better to use the kernel's alignment infrastructure to
remove the memcpy()s that are littered across persistent-data (btree,
array, space-maps, etc).
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
A rounding bug due to compiler generated temporary being 32bit was found
in remap_to_cache(). A localized cast in remap_to_cache() fixes the
corruption but this preferred fix (changing from uint32_t to sector_t)
eliminates potential for future rounding errors elsewhere.
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Firstly bio_clone_mddev() is used in raid normal I/O and isn't
in resync I/O path.
Secondly all the direct access to bvec table in raid happens on
resync I/O except for write behind of raid1, in which we still
use bio_clone() for allocating new bvec table.
So this patch replaces bio_clone() with bio_clone_fast()
in bio_clone_mddev().
Also kill bio_clone_mddev() and call bio_clone_fast() directly, as
suggested by Christoph Hellwig.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
mddev is never NULL and neither is ->bio_set, so
remove the check.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Write behind need to replace pages in bio's bvecs, and we have
to clone a fresh bio with new bvec table, so use the introduced
bio_clone_bioset_partial() for it.
For other bio_clone_mddev() cases, we will use fast clone since
they don't need to touch bvec table.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The current behaviour is to fall back to allocate
bio from 'fs_bio_set', that isn't a correct way
because it might cause deadlock.
So this patch simply return failure if mddev->bio_set
can't be created.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This makes md do the same thing as dm for write same IO failure. Please
see 7eee4ae(dm: disable WRITE SAME if it fails) for details why we need
this.
We did a little bit different than dm. Instead of disabling writesame in
the first IO error, we disable it till next writesame IO coming after
the first IO error. This way we don't need to clone a bio.
Also reported here: https://bugzilla.kernel.org/show_bug.cgi?id=118581
Suggested-by: NeilBrown <neilb@suse.com>
Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
stripes which are being reclaimed are still accounted into cached
stripes. The reclaim takes time. r5c_do_reclaim isn't aware of the
stripes and does unnecessary stripe reclaim. In practice, I saw one
stripe is reclaimed one time. This will cause bad IO pattern. Fixing
this by excluding the reclaing stripes in the check.
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When log space is tight, we try to reclaim stripes from log head. There
are stripes which can't be reclaimed right now if some conditions are
met. We skip such stripes but accidentally count them, which might cause
no stripes are claimed. Fixing this by only counting valid stripes.
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Commit: cbd1998377 ("md: Fix unfortunate interaction with evms")
change mddev_put() so that it would not destroy an md device while
->ctime was non-zero.
Unfortunately, we didn't make sure to clear ->ctime when unloading
the module, so it is possible for an md device to remain after
module unload. An attempt to open such a device will trigger
an invalid memory reference in:
get_gendisk -> kobj_lookup -> exact_lock -> get_disk
when tring to access disk->fops, which was in the module that has
been removed.
So ensure we clear ->ctime in md_exit(), and explain how that is useful,
as it isn't immediately obvious when looking at the code.
Fixes: cbd1998377 ("md: Fix unfortunate interaction with evms")
Tested-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
It is important to be able to flush all stripes in raid5-cache.
Therefore, we need reserve some space on the journal device for
these flushes. If flush operation includes pending writes to the
stripe, we need to reserve (conf->raid_disk + 1) pages per stripe
for the flush out. This reduces the efficiency of journal space.
If we exclude these pending writes from flush operation, we only
need (conf->max_degraded + 1) pages per stripe.
With this patch, when log space is critical (R5C_LOG_CRITICAL=1),
pending writes will be excluded from stripe flush out. Therefore,
we can reduce reserved space for flush out and thus improve journal
device efficiency.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Chunk aligned read significantly reduces CPU usage of raid456.
However, it is not safe to fully bypass the write back cache.
This patch enables chunk aligned read with write back cache.
For chunk aligned read, we track stripes in write back cache at
a bigger granularity, "big_stripe". Each chunk may contain more
than one stripe (for example, a 256kB chunk contains 64 4kB-page,
so this chunk contain 64 stripes). For chunk_aligned_read, these
stripes are grouped into one big_stripe, so we only need one lookup
for the whole chunk.
For each big_stripe, struct big_stripe_info tracks how many stripes
of this big_stripe are in the write back cache. We count how many
stripes of this big_stripe are in the write back cache. These
counters are tracked in a radix tree (big_stripe_tree).
r5c_tree_index() is used to calculate keys for the radix tree.
chunk_aligned_read() calls r5c_big_stripe_cached() to look up
big_stripe of each chunk in the tree. If this big_stripe is in the
tree, chunk_aligned_read() aborts. This look up is protected by
rcu_read_lock().
It is necessary to remember whether a stripe is counted in
big_stripe_tree. Instead of adding new flag, we reuses existing flags:
STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE. If either of these
two flags are set, the stripe is counted in big_stripe_tree. This
requires moving set_bit(STRIPE_R5C_PARTIAL_STRIPE) to
r5c_try_caching_write(); and moving clear_bit of
STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE to
r5c_finish_stripe_write_out().
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
We made raid5 stripe handling multi-thread before. It works well for
SSD. But for harddisk, the multi-threading creates more disk seek, so
not always improve performance. For several hard disks based raid5,
multi-threading is required as raid5d becames a bottleneck especially
for sequential write.
To overcome the disk seek issue, we only dispatch IO from raid5d if the
array is harddisk based. Other threads can still handle stripes, but
can't dispatch IO.
Idealy, we should control IO dispatching order according to IO position
interrnally. Right now we still depend on block layer, which isn't very
efficient sometimes though.
My setup has 9 harddisks, each disk can do around 180M/s sequential
write. So in theory, the raid5 can do 180 * 8 = 1440M/s sequential
write. The test machine uses an ATOM CPU. I measure sequential write
with large iodepth bandwidth to raid array:
without patch: ~600M/s
without patch and group_thread_cnt=4: 750M/s
with patch and group_thread_cnt=4: 950M/s
with patch, group_thread_cnt=4, skip_copy=1: 1150M/s
We are pretty close to the maximum bandwidth in the large iodepth
iodepth case. The performance gap of small iodepth sequential write
between software raid and theory value is still very big though, because
we don't have an efficient pipeline.
Cc: NeilBrown <neilb@suse.com>
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Recently I receive a bug report that on Linux v3.0 based kerenl, hot add
disk to a md linear device causes kernel crash at linear_congested(). From
the crash image analysis, I find in linear_congested(), mddev->raid_disks
contains value N, but conf->disks[] only has N-1 pointers available. Then
a NULL pointer deference crashes the kernel.
There is a race between linear_add() and linear_congested(), RCU stuffs
used in these two functions cannot avoid the race. Since Linuv v4.0
RCU code is replaced by introducing mddev_suspend(). After checking the
upstream code, it seems linear_congested() is not called in
generic_make_request() code patch, so mddev_suspend() cannot provent it
from being called. The possible race still exists.
Here I explain how the race still exists in current code. For a machine
has many CPUs, on one CPU, linear_add() is called to add a hard disk to a
md linear device; at the same time on other CPU, linear_congested() is
called to detect whether this md linear device is congested before issuing
an I/O request onto it.
Now I use a possible code execution time sequence to demo how the possible
race happens,
seq linear_add() linear_congested()
0 conf=mddev->private
1 oldconf=mddev->private
2 mddev->raid_disks++
3 for (i=0; i<mddev->raid_disks;i++)
4 bdev_get_queue(conf->disks[i].rdev->bdev)
5 mddev->private=newconf
In linear_add() mddev->raid_disks is increased in time seq 2, and on
another CPU in linear_congested() the for-loop iterates conf->disks[i] by
the increased mddev->raid_disks in time seq 3,4. But conf with one more
element (which is a pointer to struct dev_info type) to conf->disks[] is
not updated yet, accessing its structure member in time seq 4 will cause a
NULL pointer deference fault.
To fix this race, there are 2 parts of modification in the patch,
1) Add 'int raid_disks' in struct linear_conf, as a copy of
mddev->raid_disks. It is initialized in linear_conf(), always being
consistent with pointers number of 'struct dev_info disks[]'. When
iterating conf->disks[] in linear_congested(), use conf->raid_disks to
replace mddev->raid_disks in the for-loop, then NULL pointer deference
will not happen again.
2) RCU stuffs are back again, and use kfree_rcu() in linear_add() to
free oldconf memory. Because oldconf may be referenced as mddev->private
in linear_congested(), kfree_rcu() makes sure that its memory will not
be released until no one uses it any more.
Also some code comments are added in this patch, to make this modification
to be easier understandable.
This patch can be applied for kernels since v4.0 after commit:
3be260cc18 ("md/linear: remove rcu protections in favour of
suspend/resume"). But this bug is reported on Linux v3.0 based kernel, for
people who maintain kernels before Linux v4.0, they need to do some back
back port to this patch.
Changelog:
- V3: add 'int raid_disks' in struct linear_conf, and use kfree_rcu() to
replace rcu_call() in linear_add().
- v2: add RCU stuffs by suggestion from Shaohua and Neil.
- v1: initial effort.
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Shaohua Li <shli@fb.com>
Cc: Neil Brown <neilb@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Shaohua Li <shli@fb.com>
.. 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>
The lockdep splat below hints at a bug in RCU usage in dm-crypt that
was introduced with commit c538f6ec9f ("dm crypt: add ability to use
keys from the kernel key retention service"). The kernel keyring
function user_key_payload() is in fact a wrapper for
rcu_dereference_protected() which must not be called with only
rcu_read_lock() section mark.
Unfortunately the kernel keyring subsystem doesn't currently provide
an interface that allows the use of an RCU read-side section. So for
now we must drop RCU in favour of rwsem until a proper function is
made available in the kernel keyring subsystem.
===============================
[ INFO: suspicious RCU usage. ]
4.10.0-rc5 #2 Not tainted
-------------------------------
./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
2 locks held by cryptsetup/6464:
#0: (&md->type_lock){+.+.+.}, at: [<ffffffffa02472a2>] dm_lock_md_type+0x12/0x20 [dm_mod]
#1: (rcu_read_lock){......}, at: [<ffffffffa02822f8>] crypt_set_key+0x1d8/0x4b0 [dm_crypt]
stack backtrace:
CPU: 1 PID: 6464 Comm: cryptsetup Not tainted 4.10.0-rc5 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014
Call Trace:
dump_stack+0x67/0x92
lockdep_rcu_suspicious+0xc5/0x100
crypt_set_key+0x351/0x4b0 [dm_crypt]
? crypt_set_key+0x1d8/0x4b0 [dm_crypt]
crypt_ctr+0x341/0xa53 [dm_crypt]
dm_table_add_target+0x147/0x330 [dm_mod]
table_load+0x111/0x350 [dm_mod]
? retrieve_status+0x1c0/0x1c0 [dm_mod]
ctl_ioctl+0x1f5/0x510 [dm_mod]
dm_ctl_ioctl+0xe/0x20 [dm_mod]
do_vfs_ioctl+0x8e/0x690
? ____fput+0x9/0x10
? task_work_run+0x7e/0xa0
? trace_hardirqs_on_caller+0x122/0x1b0
SyS_ioctl+0x3c/0x70
entry_SYSCALL_64_fastpath+0x18/0xad
RIP: 0033:0x7f392c9a4ec7
RSP: 002b:00007ffef6383378 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffef63830a0 RCX: 00007f392c9a4ec7
RDX: 000000000124fcc0 RSI: 00000000c138fd09 RDI: 0000000000000005
RBP: 00007ffef6383090 R08: 00000000ffffffff R09: 00000000012482b0
R10: 2a28205d34383336 R11: 0000000000000246 R12: 00007f392d803a08
R13: 00007ffef63831e0 R14: 0000000000000000 R15: 00007f392d803a0b
Fixes: c538f6ec9f ("dm crypt: add ability to use keys from the kernel key retention service")
Reported-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fixes a crash in dm_table_find_target() due to a NULL struct dm_table
being passed from dm_old_request_fn() that races with DM device
destruction.
Reported-by: artem@flashgrid.io
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
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>
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>
DM tries to copy a few fields around for BLOCK_PC requests, but given
that no dm-target ever wires up scsi_cmd_ioctl BLOCK_PC can't actually
be sent to dm.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Return an errno value instead of the passed in queue so that the callers
don't have to keep track of two queues, and move the assignment of the
request_fn and lock to the caller as passing them as argument doesn't
simplify anything. While we're at it also remove two pointless NULL
assignments, given that the request structure is zeroed on allocation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
No need for the local variables, the bio is still live and we can just
assign the bits we want directly. Make me wonder why we can't assign
all the bio flags to start with.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This centralizes the checks for bios that needs to be go into the flush
state machine.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
For consistency, call read_disk_sb() from
attempt_restore_of_faulty_devices() instead
of calling sync_page_io() directly.
Explicitly set device to faulty on superblock read error.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add md raid4/5/6 journaling support (upstream commit bac624f3f8 started
the implementation) which closes the write hole (i.e. non-atomic updates
to stripes) using a dedicated journal device.
Background:
raid4/5/6 stripes hold N data payloads per stripe plus one parity raid4/5
or two raid6 P/Q syndrome payloads in an in-memory stripe cache.
Parity or P/Q syndromes used to recover any data payloads in case of a disk
failure are calculated from the N data payloads and need to be updated on the
different component devices of the raid device. Those are non-atomic,
persistent updates. Hence a crash can cause failure to update all stripe
payloads persistently and thus cause data loss during stripe recovery.
This problem gets addressed by writing whole stripe cache entries (together with
journal metadata) to a persistent journal entry on a dedicated journal device.
Only if that journal entry is written successfully, the stripe cache entry is
updated on the component devices of the raid device (i.e. writethrough type).
In case of a crash, the entry can be recovered from the journal and be written
again thus ensuring consistent stripe payload suitable to data recovery.
Future dependencies:
once writeback caching being worked on to compensate for the throughput
implictions involved with writethrough overhead is supported with journaling
in upstream, an additional patch based on this one will support it in dm-raid.
Journal resilience related remarks:
because stripes are recovered from the journal in case of a crash, the
journal device better be resilient. Resilience becomes mandatory with
future writeback support, because loosing the working set in the log
means data loss as oposed to writethrough, were the loss of the
journal device 'only' reintroduces the write hole.
Fix comment on data offsets in parse_dev_params() and initialize
new_data_offset as well.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
During raid set resize checks and setting up the recovery offset in case a raid
set grows, calculated rd->md.dev_sectors is compared to rs->dev[0].rdev.sectors.
Device 0 may not be defined in case userspace passes in '- -' for it
(lvm2 doesn't do that so far), thus it's device sectors can't be taken
authoritatively in this comparison and another valid device must be used
to retrieve the device size.
Use mddev->dev_sectors in checking for ongoing recovery for the same reason.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This fix addresses the following 3 failure scenarios:
1) If a (transiently) inaccessible metadata device is being passed into the
constructor (e.g. a device tuple '254:4 254:5'), it is processed as if
'- -' was given. This erroneously results in a status table line containing
'- -', which mistakenly differs from what has been passed in. As a result,
userspace libdevmapper puts the device tuple seperate from the RAID device
thus not processing the dependencies properly.
2) False health status char 'A' instead of 'D' is emitted on the status
status info line for the meta/data device tuple in this metadata device
failure case.
3) If the metadata device is accessible when passed into the constructor
but the data device (partially) isn't, that leg may be set faulty by the
raid personality on access to the (partially) unavailable leg. Restore
tried in a second raid device resume on such failed leg (status char 'D')
fails after the (partial) leg returned.
Fixes for aforementioned failure scenarios:
- don't release passed in devices in the constructor thus allowing the
status table line to e.g. contain '254:4 254:5' rather than '- -'
- emit device status char 'D' rather than 'A' for the device tuple
with the failed metadata device on the status info line
- when attempting to restore faulty devices in a second resume, allow the
device hot remove function to succeed by setting the device to not in-sync
In case userspace intentionally passes '- -' into the constructor to avoid that
device tuple (e.g. to split off a raid1 leg temporarily for later re-addition),
the status table line will correctly show '- -' and the status info line will
provide a '-' device health character for the non-defined device tuple.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
write-back cache in degraded mode introduces corner cases to the array.
Although we try to cover all these corner cases, it is safer to just
disable write-back cache when the array is in degraded mode.
In this patch, we disable writeback cache for degraded mode:
1. On device failure, if the array enters degraded mode, raid5_error()
will submit async job r5c_disable_writeback_async to disable
writeback;
2. In r5c_journal_mode_store(), it is invalid to enable writeback in
degraded mode;
3. In r5c_try_caching_write(), stripes with s->failed>0 will be handled
in write-through mode.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Write back cache requires a complex RMW mechanism, where old data is
read into dev->orig_page for prexor, and then xor is done with
dev->page. This logic is already implemented in the write path.
However, current read path is not awared of this requirement. When
the array is optimal, the RMW is not required, as the data are
read from raid disks. However, when the target stripe is degraded,
complex RMW is required to generate right data.
To keep read path as clean as possible, we handle read path by
flushing degraded, in-journal stripes before processing reads to
missing dev.
Specifically, when there is read requests to a degraded stripe
with data in journal, handle_stripe_fill() calls
r5c_make_stripe_write_out() and exits. Then handle_stripe_dirtying()
will do the complex RMW and flush the stripe to RAID disks. After
that, read requests are handled.
There is one more corner case when there is non-overwrite bio for
the missing (or out of sync) dev. handle_stripe_dirtying() will not
be able to process the non-overwrite bios without constructing the
data in handle_stripe_fill(). This is fixed by delaying non-overwrite
bios in handle_stripe_dirtying(). So handle_stripe_fill() works on
these bios after the stripe is flushed to raid disks.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
For safer operation, all arrays start in write-through mode, which has been
better tested and is more mature. And actually the write-through/write-mode
isn't persistent after array restarted, so we always start array in
write-through mode. However, if recovery found data-only stripes before the
shutdown (from previous write-back mode), it is not safe to start the array in
write-through mode, as write-through mode can not handle stripes with data in
write-back cache. To solve this problem, we flush all data-only stripes in
r5l_recovery_log(). When r5l_recovery_log() returns, the array starts with
empty cache in write-through mode.
This logic is implemented in r5c_recovery_flush_data_only_stripes():
1. enable write back cache
2. flush all stripes
3. wake up conf->mddev->thread
4. wait for all stripes get flushed (reuse wait_for_quiescent)
5. disable write back cache
The wait in 4 will be waked up in release_inactive_stripe_list()
when conf->active_stripes reaches 0.
It is safe to wake up mddev->thread here because all the resource
required for the thread has been initialized.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
