For sequential workload (or request size big workload), get_active_stripe can
find cached stripe. In this case, we always hold device_lock, which exposes a
lot of lock contention for such workload. If stripe count isn't 0, we don't
need hold the lock actually, since we just increase its count. And this is the
hot code path for such workload. Unfortunately we must delete the BUG_ON.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In NUMA machine, prepare_to_wait/finish_wait in make_request exposes a
lot of contention for sequential workload (or big request size
workload). For such workload, each bio includes several stripes. So we
can just do prepare_to_wait/finish_wait once for the whold bio instead
of every stripe. This reduces the lock contention completely for such
workload. Random workload might have the similar lock contention too,
but I didn't see it yet, maybe because my stroage is still not fast
enough.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If md-mod is unloaded while some process is in poll() or select(),
then that process maintains a pointer to md_event_waiters, and when
the try to unlink from that list, they will oops.
The procfs infrastructure ensures that ->poll won't be called after
remove_proc_entry, but doesn't provide a wait_queue_head for us to
use, and the waitqueue code doesn't provide a way to remove all
listeners from a waitqueue.
So we need to:
1/ make sure no further references to md_event_waiters are taken (by
setting md_unloading)
2/ wake up all processes currently waiting, and
3/ wait until all those processes have disconnected from our
wait_queue_head.
Reported-by: "majianpeng" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When performing a user-request check/repair (MD_RECOVERY_REQUEST is set)
on a raid1, we allocate multiple bios each with their own set of pages.
If the page allocations for one bio fails, we currently do *not* free
the pages allocated for the previous bios, nor do we free the bio itself.
This patch frees all the already-allocate pages, and makes sure that
all the bios are freed as well.
This bug can cause a memory leak which can ultimately OOM a machine.
It was introduced in 3.10-rc1.
Fixes: a07876064a
Cc: Kent Overstreet <koverstreet@google.com>
Cc: stable@vger.kernel.org (3.10+)
Reported-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Signed-off-by: NeilBrown <neilb@suse.de>
md bitmap code currently tries to use i_writecount to stop any other
process from writing to out bitmap file. But that is really an abuse
and has bit-rotted so locking is all wrong.
So discard that - root should be allowed to shoot self in foot.
Still use it in a much less intrusive way to stop the same file being
used as bitmap on two different array, and apply other checks to
ensure the file is at least vaguely usable for bitmap storage
(is regular, is open for write. Support for ->bmap is already checked
elsewhere).
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NeilBrown <neilb@suse.de>
Commit c140e1c4e2 ("dm thin: use per thin device deferred bio lists")
introduced the use of an rculist for all active thin devices. The use
of rcu_read_lock() in process_deferred_bios() can result in a BUG if a
dm_bio_prison_cell must be allocated as a side-effect of bio_detain():
BUG: sleeping function called from invalid context at mm/mempool.c:203
in_atomic(): 1, irqs_disabled(): 0, pid: 6, name: kworker/u8:0
3 locks held by kworker/u8:0/6:
#0: ("dm-" "thin"){.+.+..}, at: [<ffffffff8106be42>] process_one_work+0x192/0x550
#1: ((&pool->worker)){+.+...}, at: [<ffffffff8106be42>] process_one_work+0x192/0x550
#2: (rcu_read_lock){.+.+..}, at: [<ffffffff816360b5>] do_worker+0x5/0x4d0
We can't process deferred bios with the rcu lock held, since
dm_bio_prison_cell allocation may block if the bio-prison's cell mempool
is exhausted.
To fix:
- Introduce a refcount and completion field to each thin_c
- Add thin_get/put methods for adjusting the refcount. If the refcount
hits zero then the completion is triggered.
- Initialise refcount to 1 when creating thin_c
- When iterating the active_thins list we thin_get() whilst the rcu
lock is held.
- After the rcu lock is dropped we process the deferred bios for that
thin.
- When destroying a thin_c we thin_put() and then wait for the
completion -- to avoid a race between the worker thread iterating
from that thin_c and destroying the thin_c.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit c140e1c4e2 ("dm thin: use per thin device deferred bio lists")
incorrectly stopped disabling irqs when taking the pool's spinlock.
Irqs must be disabled when taking the pool's spinlock otherwise a thread
could spin_lock(), then get interrupted to service thin_endio() in
interrupt context, which would then deadlock in spin_lock_irqsave().
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
cache_block_size
. Fix a lock-inversion detected by LOCKDEP in dm-cache
. Fix a dangling bio bug in the dm-thinp target's process_deferred_bios
error path
. Fix corruption due to non-atomic transaction commit which allowed a
metadata superblock to be written before all other metadata was
successfully written -- this is common to all targets that use the
persistent-data library's transaction manager (dm-thinp, dm-cache and
dm-era).
. Various small cleanups in the DM core
. Add the dm-era target which is useful for keeping track of which
blocks were written within a user defined period of time called an
'era'. Use cases include tracking changed blocks for backup software,
and partially invalidating the contents of a cache to restore cache
coherency after rolling back a vendor snapshot.
. Improve the on-disk layout of multithreaded writes to the dm-thin-pool
by splitting the pool's deferred bio list to be a per-thin device list
and then sorting that list using an rb_tree. The subsequent read
throughput of the data written via multiple threads improved by ~70%.
. Simplify the multipath target's handling of queuing IO by pushing
requests back to the request queue rather than queueing the IO
internally.
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Merge tag 'dm-3.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper changes from Mike Snitzer:
- Fix dm-cache corruption caused by discard_block_size > cache_block_size
- Fix a lock-inversion detected by LOCKDEP in dm-cache
- Fix a dangling bio bug in the dm-thinp target's process_deferred_bios
error path
- Fix corruption due to non-atomic transaction commit which allowed a
metadata superblock to be written before all other metadata was
successfully written -- this is common to all targets that use the
persistent-data library's transaction manager (dm-thinp, dm-cache and
dm-era).
- Various small cleanups in the DM core
- Add the dm-era target which is useful for keeping track of which
blocks were written within a user defined period of time called an
'era'. Use cases include tracking changed blocks for backup
software, and partially invalidating the contents of a cache to
restore cache coherency after rolling back a vendor snapshot.
- Improve the on-disk layout of multithreaded writes to the
dm-thin-pool by splitting the pool's deferred bio list to be a
per-thin device list and then sorting that list using an rb_tree.
The subsequent read throughput of the data written via multiple
threads improved by ~70%.
- Simplify the multipath target's handling of queuing IO by pushing
requests back to the request queue rather than queueing the IO
internally.
* tag 'dm-3.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (24 commits)
dm cache: fix a lock-inversion
dm thin: sort the per thin deferred bios using an rb_tree
dm thin: use per thin device deferred bio lists
dm thin: simplify pool_is_congested
dm thin: fix dangling bio in process_deferred_bios error path
dm mpath: print more useful warnings in multipath_message()
dm-mpath: do not activate failed paths
dm mpath: remove extra nesting in map function
dm mpath: remove map_io()
dm mpath: reduce memory pressure when requeuing
dm mpath: remove process_queued_ios()
dm mpath: push back requests instead of queueing
dm table: add dm_table_run_md_queue_async
dm mpath: do not call pg_init when it is already running
dm: use RCU_INIT_POINTER instead of rcu_assign_pointer in __unbind
dm: stop using bi_private
dm: remove dm_get_mapinfo
dm: make dm_table_alloc_md_mempools static
dm: take care to copy the space map roots before locking the superblock
dm transaction manager: fix corruption due to non-atomic transaction commit
...
When suspending a cache the policy is walked and the individual policy
hints written to the metadata via sync_metadata(). This led to this
lock order:
policy->lock
cache_metadata->root_lock
When loading the cache target the policy is populated while the metadata
lock is held:
cache_metadata->root_lock
policy->lock
Fix this potential lock-inversion (ABBA) deadlock in sync_metadata() by
ensuring the cache_metadata root_lock is held whilst all the hints are
written, rather than being repeatedly locked while policy->lock is held
(as was the case with each callout that policy_walk_mappings() made to
the old save_hint() method).
Found by turning on the CONFIG_PROVE_LOCKING ("Lock debugging: prove
locking correctness") build option. However, it is not clear how the
LOCKDEP reported paths can lead to a deadlock since the two paths,
suspending a target and loading a target, never occur at the same time.
But that doesn't mean the same lock-inversion couldn't have occurred
elsewhere.
Reported-by: Marian Csontos <mcsontos@redhat.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
A thin-pool will allocate blocks using FIFO order for all thin devices
which share the thin-pool. Because of this simplistic allocation the
thin-pool's space can become fragmented quite easily; especially when
multiple threads are requesting blocks in parallel.
Sort each thin device's deferred_bio_list based on logical sector to
help reduce fragmentation of the thin-pool's ondisk layout.
The following tables illustrate the realized gains/potential offered by
sorting each thin device's deferred_bio_list. An "io size"-sized random
read of the device would result in "seeks/io" fragments being read, with
an average "distance/seek" between each fragment.
Data was written to a single thin device using multiple threads via
iozone (8 threads, 64K for both the block_size and io_size).
unsorted:
io size seeks/io distance/seek
--------------------------------------
4k 0.000 0b
16k 0.013 11m
64k 0.065 11m
256k 0.274 10m
1m 1.109 10m
4m 4.411 10m
16m 17.097 11m
64m 60.055 13m
256m 148.798 25m
1g 809.929 21m
sorted:
io size seeks/io distance/seek
--------------------------------------
4k 0.000 0b
16k 0.000 1g
64k 0.001 1g
256k 0.003 1g
1m 0.011 1g
4m 0.045 1g
16m 0.181 1g
64m 0.747 1011m
256m 3.299 1g
1g 14.373 1g
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Pull block driver update from Jens Axboe:
"On top of the core pull request, here's the pull request for the
driver related changes for 3.15. It contains:
- Improvements for msi-x registration for block drivers (mtip32xx,
skd, cciss, nvme) from Alexander Gordeev.
- A round of cleanups and improvements for drbd from Andreas
Gruenbacher and Rashika Kheria.
- A round of clanups and improvements for bcache from Kent.
- Removal of sleep_on() and friends in DAC960, ataflop, swim3 from
Arnd Bergmann.
- Bug fix for a bug in the mtip32xx async completion code from Sam
Bradshaw.
- Bug fix for accidentally bouncing IO on 32-bit platforms with
mtip32xx from Felipe Franciosi"
* 'for-3.15/drivers' of git://git.kernel.dk/linux-block: (103 commits)
bcache: remove nested function usage
bcache: Kill bucket->gc_gen
bcache: Kill unused freelist
bcache: Rework btree cache reserve handling
bcache: Kill btree_io_wq
bcache: btree locking rework
bcache: Fix a race when freeing btree nodes
bcache: Add a real GC_MARK_RECLAIMABLE
bcache: Add bch_keylist_init_single()
bcache: Improve priority_stats
bcache: Better alloc tracepoints
bcache: Kill dead cgroup code
bcache: stop moving_gc marking buckets that can't be moved.
bcache: Fix moving_pred()
bcache: Fix moving_gc deadlocking with a foreground write
bcache: Fix discard granularity
bcache: Fix another bug recovering from unclean shutdown
bcache: Fix a bug recovering from unclean shutdown
bcache: Fix a journalling reclaim after recovery bug
bcache: Fix a null ptr deref in journal replay
...
Here's the big char/misc driver updates for 3.15-rc1.
Lots of various things here, including the new mcb driver subsystem.
All of these have been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver patches from Greg KH:
"Here's the big char/misc driver updates for 3.15-rc1.
Lots of various things here, including the new mcb driver subsystem.
All of these have been in linux-next for a while"
* tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (118 commits)
extcon: Move OF helper function to extcon core and change function name
extcon: of: Remove unnecessary function call by using the name of device_node
extcon: gpio: Use SIMPLE_DEV_PM_OPS macro
extcon: palmas: Use SIMPLE_DEV_PM_OPS macro
mei: don't use deprecated DEFINE_PCI_DEVICE_TABLE macro
mei: amthif: fix checkpatch error
mei: client.h fix checkpatch errors
mei: use cl_dbg where appropriate
mei: fix Unnecessary space after function pointer name
mei: report consistently copy_from/to_user failures
mei: drop pr_fmt macros
mei: make me hw headers private to me hw.
mei: fix memory leak of pending write cb objects
mei: me: do not reset when less than expected data is received
drivers: mcb: Fix build error discovered by 0-day bot
cs5535-mfgpt: Simplify dependencies
spmi: pm: drop bus-level PM suspend/resume routines
spmi: pmic_arb: make selectable on ARCH_QCOM
Drivers: hv: vmbus: Increase the limit on the number of pfns we can handle
pch_phub: Report error writing MAC back to user
...
The thin-pool previously only had a single deferred_bios list that would
collect bios for all thin devices in the pool. Split this per-pool
deferred_bios list out to per-thin deferred_bios_list -- doing so
enables increased parallelism when processing deferred bios. And now
that each thin device has it's own deferred_bios_list we can sort all
bios in the list using logical sector. The requeue code in error
handling path is also cleaner as a side-effect.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
The pool is congested if the pool is in PM_OUT_OF_DATA_SPACE mode. This
is more explicit/clear/efficient than inferring whether or not the pool
is congested by checking if retry_on_resume_list is empty.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
If unable to ensure_next_mapping() we must add the current bio, which
was removed from the @bios list via bio_list_pop, back to the
deferred_bios list before all the remaining @bios.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
The warning message "Unrecognised multipath message received" is
displayed in two different situations in multipath_message(): when the
number of arguments passed is invalid and when the string passed in
argv[0] is not recognized.
Make it easier to identify where the problem is by making these warnings
more specific with additional context for each case.
Signed-off-by: Jose Castillo <jcastillo@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
activate_path() is run without a lock, so the path might be
set to failed before activate_path() had a chance to run.
This patch add a check for ->active in activate_path() to
avoid unnecessary overhead by calling functions which are known
to be failing.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Return early for case when no path exists, and when the
pathgroup isn't ready. This eliminates the need for
extra nesting for the the common case.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
multipath_map() is now just a wrapper around map_io(), so we
can rename map_io() to multipath_map().
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
When multipath needs to requeue I/O in the block layer the per-request
context shouldn't be allocated, as it will be freed immediately
afterwards anyway. Avoiding this memory allocation will reduce memory
pressure during requeuing.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
process_queued_ios() has served 3 functions:
1) select pg and pgpath if none is selected
2) start pg_init if requested
3) dispatch queued IOs when pg is ready
Basically, a call to queue_work(process_queued_ios) can be replaced by
dm_table_run_md_queue_async(), which runs request queue and ends up
calling map_io(), which does 1), 2) and 3).
Exception is when !pg_ready() (which means either pg_init is running or
requested), then multipath_busy() prevents map_io() being called from
request_fn.
If pg_init is running, it should be ok as long as pg_init_done() does
the right thing when pg_init is completed, I.e.: restart pg_init if
!pg_ready() or call dm_table_run_md_queue_async() to kick map_io().
If pg_init is requested, we have to make sure the request is detected
and pg_init will be started. pg_init is requested in 3 places:
a) __choose_pgpath() in map_io()
b) __choose_pgpath() in multipath_ioctl()
c) pg_init retry in pg_init_done()
a) is ok because map_io() calls __pg_init_all_paths(), which does 2).
b) needs a call to __pg_init_all_paths(), which does 2).
c) needs a call to __pg_init_all_paths(), which does 2).
So this patch removes process_queued_ios() and ensures that
__pg_init_all_paths() is called at the appropriate locations.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
There is no reason why multipath needs to queue requests internally for
queue_if_no_path or pg_init; we should rather push them back onto the
request queue.
And while we're at it we can simplify the conditional statement in
map_io() to make it easier to read.
Since mpath no longer does internal queuing of I/O the table info no
longer emits the internal queue_size. Instead it displays 1 if queuing
is being used or 0 if it is not.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Introduce dm_table_run_md_queue_async() to run the request_queue of the
mapped_device associated with a request-based DM table.
Also add dm_md_get_queue() wrapper to extract the request_queue from a
mapped_device.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
This patch moves condition checks as a preparation of following
patches and has no effect on behaviour.
process_queued_ios() is the only caller of __pg_init_all_paths()
and 2 condition checks are moved from outside to inside without
side effects.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Replace rcu_assign_pointer(p, NULL) with RCU_INIT_POINTER(p, NULL).
The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure. And in the
case of the NULL pointer, there is no structure to initialize. So,
rcu_assign_pointer(p, NULL) can be safely converted to
RCU_INIT_POINTER(p, NULL).
Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Device mapper uses the bio structure's bi_private field as a pointer
to dm_target_io or dm_rq_clone_bio_info. But a bio structure is
embedded in the dm_target_io and dm_rq_clone_bio_info structures, so the
pointer to the structure that contains the bio can be found with the
container_of() macro.
Remove the use of bi_private and use container_of() instead.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Remove dm_get_mapinfo() because no target uses it. Targets can allocate
per-bio data using ti->per_bio_data_size, this is much more flexible
than union map_info.
Leave union map_info only for the request-based multipath target's use.
Also delete the unused "unsigned long long ll" field of union map_info.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Make the function dm_table_alloc_md_mempools static because it is not
called from another file.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In theory copying the space map root can fail, but in practice it never
does because we're careful to check what size buffer is needed.
But make certain we're able to copy the space map roots before
locking the superblock.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # drop dm-era and dm-cache changes as needed
The persistent-data library used by dm-thin, dm-cache, etc is
transactional. If anything goes wrong, such as an io error when writing
new metadata or a power failure, then we roll back to the last
transaction.
Atomicity when committing a transaction is achieved by:
a) Never overwriting data from the previous transaction.
b) Writing the superblock last, after all other metadata has hit the
disk.
This commit and the following commit ("dm: take care to copy the space
map roots before locking the superblock") fix a bug associated with (b).
When committing it was possible for the superblock to still be written
in spite of an io error occurring during the preceeding metadata flush.
With these commits we're careful not to take the write lock out on the
superblock until after the metadata flush has completed.
Change the transaction manager's semantics for dm_tm_commit() to assume
all data has been flushed _before_ the single superblock that is passed
in.
As a prerequisite, split the block manager's block unlocking and
flushing by simplifying dm_bm_flush_and_unlock() to dm_bm_flush(). Now
the unlocking must be done separately.
This issue was discovered by forcing io errors at the crucial time
using dm-flakey.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
Discard block size not being equal to cache block size causes data
corruption by erroneously avoiding migrations in issue_copy() because
the discard state is being cleared for a group of cache blocks when it
should not.
Completely remove all code that enabled a distinction between the
cache block size and discard block size.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If the discard block size is larger than the cache block size we will
not properly quiesce IO to a region that is about to be discarded. This
results in a race between a cache migration where no copy is needed, and
a write to an adjacent cache block that's within the same large discard
block.
Workaround this by limiting the discard_block_size to cache_block_size.
Also limit the max_discard_sectors to cache_block_size.
A more comprehensive fix that introduces range locking support in the
bio_prison and proper quiescing of a discard range that spans multiple
cache blocks is already in development.
Reported-by: Morgan Mears <Morgan.Mears@netapp.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Acked-by: Heinz Mauelshagen <heinzm@redhat.com>
Cc: stable@vger.kernel.org
dm-era is a target that behaves similar to the linear target. In
addition it keeps track of which blocks were written within a user
defined period of time called an 'era'. Each era target instance
maintains the current era as a monotonically increasing 32-bit
counter.
Use cases include tracking changed blocks for backup software, and
partially invalidating the contents of a cache to restore cache
coherency after rolling back a vendor snapshot.
dm-era is primarily expected to be paired with the dm-cache target.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Uninlined nested functions can cause crashes when using ftrace, as they don't
follow the normal calling convention and confuse the ftrace function graph
tracer as it examines the stack.
Also, nested functions are supported as a gcc extension, but may fail on other
compilers (e.g. llvm).
Signed-off-by: John Sheu <john.sheu@gmail.com>
gc_gen was a temporary used to recalculate last_gc, but since we only need
bucket->last_gc when gc isn't running (gc_mark_valid = 1), we can just update
last_gc directly.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This was originally added as at optimization that for various reasons isn't
needed anymore, but it does add a lot of nasty corner cases (and it was
responsible for some recently fixed bugs). Just get rid of it now.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This changes the bucket allocation reserves to use _real_ reserves - separate
freelists - instead of watermarks, which if nothing else makes the current code
saner to reason about and is going to be important in the future when we add
support for multiple btrees.
It also adds btree_check_reserve(), which checks (and locks) the reserves for
both bucket allocation and memory allocation for btree nodes; the old code just
kinda sorta assumed that since (e.g. for btree node splits) it had the root
locked and that meant no other threads could try to make use of the same
reserve; this technically should have been ok for memory allocation (we should
always have a reserve for memory allocation (the btree node cache is used as a
reserve and we preallocate it)), but multiple btrees will mean that locking the
root won't be sufficient anymore, and for the bucket allocation reserve it was
technically possible for the old code to deadlock.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
With the locking rework in the last patch, this shouldn't be needed anymore -
btree_node_write_work() only takes b->write_lock which is never held for very
long.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Add a new lock, b->write_lock, which is required to actually modify - or write -
a btree node; this lock is only held for short durations.
This means we can write out a btree node without taking b->lock, which _is_ held
for long durations - solving a deadlock when btree_flush_write() (from the
journalling code) is called with a btree node locked.
Right now just occurs in bch_btree_set_root(), but with an upcoming journalling
rework is going to happen a lot more.
This also turns b->lock is now more of a read/intent lock instead of a
read/write lock - but not completely, since it still blocks readers. May turn it
into a real intent lock at some point in the future.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This isn't a bulletproof fix; btree_node_free() -> bch_bucket_free() puts the
bucket on the unused freelist, where it can be reused right away without any
ordering requirements. It would be better to wait on at least a journal write to
go down before reusing the bucket. bch_btree_set_root() does this, and inserting
into non leaf nodes is completely synchronous so we should be ok, but future
patches are just going to get rid of the unused freelist - it was needed in the
past for various reasons but shouldn't be anymore.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This means the garbage collection code can better check for data and metadata
pointers to the same buckets.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This will potentially save us an allocation when we've got inode/dirent bkeys
that don't fit in the keylist's inline keys.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Change the invalidate tracepoint to indicate how much data we're invalidating,
and change the alloc tracepoints to indicate what offset they're for.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Deadlock happened because a foreground write slept, waiting for a bucket
to be allocated. Normally the gc would mark buckets available for invalidation.
But the moving_gc was stuck waiting for outstanding writes to complete.
These writes used the bcache_wq, the same queue foreground writes used.
This fix gives moving_gc its own work queue, so it was still finish moving
even if foreground writes are stuck waiting for allocation. It also makes
work queue a parameter to the data_insert path, so moving_gc can use its
workqueue for writes.
Signed-off-by: Nicholas Swenson <nks@daterainc.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
The on disk bucket gens are allowed to be out of date, when we reuse buckets
that didn't have any live data in them. To deal with this, the initial gc has to
update the bucket gen when we find a pointer gen newer than the bucket's gen.
Unfortunately we weren't doing this for pointers in the journal that we're about
to replay.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
On recovery we weren't correctly keeping track of what journal buckets had open
journal entries, thus it was possible for them to be overwritten until we'd
written all new journal entries.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
In order to avoid wasting cache space a partial block at the end of the
origin device is not cached. Unfortunately, the check for such a
partial block at the end of the origin device was flawed.
Fix accesses beyond the end of the origin device that occured due to
attempted promotion of an undetected partial block by:
- initializing the per bio data struct to allow cache_end_io to work properly
- recognizing access to the partial block at the end of the origin device
- avoiding out of bounds access to the discard bitset
Otherwise, users can experience errors like the following:
attempt to access beyond end of device
dm-5: rw=0, want=20971520, limit=20971456
...
device-mapper: cache: promotion failed; couldn't copy block
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
During demotion or promotion to a cache's >2TB fast device we must not
truncate the cache block's associated sector to 32bits. The 32bit
temporary result of from_cblock() caused a 32bit multiplication when
calculating the sector of the fast device in issue_copy_real().
Use an intermediate 64bit type to store the 32bit from_cblock() to allow
for proper 64bit multiplication.
Here is an example of how this bug manifests on an ext4 filesystem:
EXT4-fs error (device dm-0): ext4_mb_generate_buddy:756: group 17136, 32768 clusters in bitmap, 30688 in gd; block bitmap corrupt.
JBD2: Spotted dirty metadata buffer (dev = dm-0, blocknr = 0). There's a risk of filesystem corruption in case of system crash.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
This has been a relatively long-standing issue that wasn't nailed down
until Teng-Feng Yang's meticulous bug report to dm-devel on 3/7/2014,
see: http://www.redhat.com/archives/dm-devel/2014-March/msg00021.html
From that report:
"When decreasing the reference count of a metadata block with its
reference count equals 3, we will call dm_btree_remove() to remove
this enrty from the B+tree which keeps the reference count info in
metadata device.
The B+tree will try to rebalance the entry of the child nodes in each
node it traversed, and the rebalance process contains the following
steps.
(1) Finding the corresponding children in current node (shadow_current(s))
(2) Shadow the children block (issue BOP_INC)
(3) redistribute keys among children, and free children if necessary (issue BOP_DEC)
Since the update of a metadata block's reference count could be
recursive, we will stash these reference count update operations in
smm->uncommitted and then process them in a FILO fashion.
The problem is that step(3) could free the children which is created
in step(2), so the BOP_DEC issued in step(3) will be carried out
before the BOP_INC issued in step(2) since these BOPs will be
processed in FILO fashion. Once the BOP_DEC from step(3) tries to
decrease the reference count of newly shadow block, it will report
failure for its reference equals 0 before decreasing. It looks like we
can solve this issue by processing these BOPs in a FIFO fashion
instead of FILO."
Commit 5b564d80 ("dm space map: disallow decrementing a reference count
below zero") changed the code to report an error for this temporary
refcount decrement below zero. So what was previously a harmless
invalid refcount became a hard failure due to the new error path:
device-mapper: space map common: unable to decrement a reference count below 0
device-mapper: thin: 253:6: dm_thin_insert_block() failed: error = -22
device-mapper: thin: 253:6: switching pool to read-only mode
This bug is in dm persistent-data code that is common to the DM thin and
cache targets. So any users of those targets should apply this fix.
Fix this by applying recursive space map operations in FIFO order rather
than FILO.
Resolves: https://bugzilla.kernel.org/show_bug.cgi?id=68801
Reported-by: Apollon Oikonomopoulos <apoikos@debian.org>
Reported-by: edwillam1007@gmail.com
Reported-by: Teng-Feng Yang <shinrairis@gmail.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 3.13+
i) by the time DM core calls the postsuspend hook the dm_noflush flag
has been cleared. So the old thin_postsuspend did nothing. We need to
use the presuspend hook instead.
ii) There was a race between bios leaving DM core and arriving in the
deferred queue.
thin_presuspend now sets a 'requeue' flag causing all bios destined for
that thin to be requeued back to DM core. Then it requeues all held IO,
and all IO on the deferred queue (destined for that thin). Finally
postsuspend clears the 'requeue' flag.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The spin lock in requeue_io() was held for too long, allowing deadlock.
Don't worry, due to other issues addressed in the following "dm thin:
fix noflush suspend IO queueing" commit, this code was never called.
Fix this by taking the spin lock for a much shorter period of time.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Ideally a thin pool would never run out of data space; the low water
mark would trigger userland to extend the pool before we completely run
out of space. However, many small random IOs to unprovisioned space can
consume data space at an alarming rate. Adjust your low water mark if
you're frequently seeing "out-of-data-space" mode.
Before this fix, if data space ran out the pool would be put in
PM_READ_ONLY mode which also aborted the pool's current metadata
transaction (data loss for any changes in the transaction). This had a
side-effect of needlessly compromising data consistency. And retry of
queued unserviceable bios, once the data pool was resized, could
initiate changes to potentially inconsistent pool metadata.
Now when the pool's data space is exhausted transition to a new pool
mode (PM_OUT_OF_DATA_SPACE) that allows metadata to be changed but data
may not be allocated. This allows users to remove thin volumes or
discard data to recover data space.
The pool is no longer put in PM_READ_ONLY mode in response to the pool
running out of data space. And PM_READ_ONLY mode no longer aborts the
pool's current metadata transaction. Also, set_pool_mode() will now
notify userspace when the pool mode is changed.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If a thin metadata operation fails the current transaction will abort,
whereby causing potential for IO layers up the stack (e.g. filesystems)
to have data loss. As such, set THIN_METADATA_NEEDS_CHECK_FLAG in the
thin metadata's superblock which:
1) requires the user verify the thin metadata is consistent (e.g. use
thin_check, etc)
2) suggests the user verify the thin data is consistent (e.g. use fsck)
The only way to clear the superblock's THIN_METADATA_NEEDS_CHECK_FLAG is
to run thin_repair.
On metadata operation failure: abort current metadata transaction, set
pool in read-only mode, and now set the needs_check flag.
As part of this change, constraints are introduced or relaxed:
* don't allow a pool to transition to write mode if needs_check is set
* don't allow data or metadata space to be resized if needs_check is set
* if a thin pool's metadata space is exhausted: the kernel will now
force the user to take the pool offline for repair before the kernel
will allow the metadata space to be extended.
Also, update Documentation to include information about when the thin
provisioning target commits metadata, how it handles metadata failures
and running out of space.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Commit b5330655 ("dm thin: handle metadata failures more consistently")
increased potential for the pool's mode to be changed in response to
metadata operation failures.
When the pool mode is changed it isn't synchronized with the mode in
pool_features stored in the target's context (ti->private) that is used
as the basis for (re)establishing the pool mode during resume via
bind_control_target.
It is important that we synchronize the pool mode when it is changed
otherwise the pool may experience and unexpected mode transition on the
next resume (especially if there was no new table load).
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Commit 55494bf294 ("dm snapshot: use dm-bufio") broke snapshots.
Before that 3.14-rc1 commit, loading a snapshot's list of exceptions
involved reading exception areas one by one into ps->area and inserting
those exceptions into the hash table. Commit 55494bf294 changed
it so that dm-bufio with prefetch is used to load exceptions in batchs.
Exceptions are loaded correctly, but ps->area is left uninitialized.
When a new exception is allocated, it is stored in this uninitialized
ps->area which will be written to the disk. This causes metadata
corruption.
Fix this corruption by copying the last area that was read via dm-bufio
into ps->area.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Since DM_DEBUG_BLOCK_STACK_TRACING is a DM_PERSISTENT_DATA config option
move it from drivers/md/Kconfig to drivers/md/persistent-data/Kconfig.
Doing so fixes indentation for other DM config options.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When remapping a block to the cache's fast device that is larger than
2TB we must not truncate the destination sector to 32bits. The 32bit
temporary result of from_cblock() was being overflowed in
remap_to_cache() due to the logical left shift.
Use an intermediate 64bit type to store the 32bit from_cblock() result
to fix the overflow.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
It was always intended that a user could provide a thin metadata device
that is larger than the max supported by the on-disk format. The extra
space would just go unused.
Unfortunately that never worked. If the user attempted to use a larger
metadata device on creation they would get an error like the following:
device-mapper: space map common: space map too large
device-mapper: transaction manager: couldn't create metadata space map
device-mapper: thin metadata: tm_create_with_sm failed
device-mapper: table: 252:17: thin-pool: Error creating metadata object
device-mapper: ioctl: error adding target to table
Fix this by allowing the initial metadata space map creation to cap its
size at the max number of blocks supported (DM_SM_METADATA_MAX_BLOCKS).
get_metadata_dev_size() must also impose DM_SM_METADATA_MAX_BLOCKS (via
THIN_METADATA_MAX_SECTORS), otherwise extending metadata would cap at
THIN_METADATA_MAX_SECTORS_WARNING (which is larger than supported).
Also, the calculation for THIN_METADATA_MAX_SECTORS didn't account for
the sizeof the disk_bitmap_header. So the supported maximum metadata
size is a bit smaller (reduced from 33423360 to 33292800 sectors).
Lastly, remove the "excess space will not be used" warning message from
get_metadata_dev_size(); it resulted in printing the warning multiple
times. Factor out warn_if_metadata_device_too_big(), call it from
pool_ctr() and maybe_resize_metadata_dev().
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
An invalid ioctl will never be valid, irrespective of whether multipath
has active paths or not. So for invalid ioctls we do not have to wait
for multipath to activate any paths, but can rather return an error
code immediately. This fix resolves numerous instances of:
udevd[]: worker [] unexpectedly returned with status 0x0100
that have been seen during testing.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
The code was using sectors to count the number of sectors it was zeroing... but
then it passed it to bio_advance()... after it had been set to 0. Amusing...
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
dm_pool_close_thin_device() must be called if dm_set_target_max_io_len()
fails in thin_ctr(). Otherwise __pool_destroy() will fail because the
pool will still have an open thin device:
device-mapper: thin metadata: attempt to close pmd when 1 device(s) are still open
device-mapper: thin: __pool_destroy: dm_pool_metadata_close() failed.
Also, must establish error code if failing thin_ctr() because the pool
is in fail_io mode.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
When restoring bi_end_io, increase bi_remaining before retrying the bio
to avoid BUG_ON(atomic_read(&bio->bi_remaining) <= 0) in bio_endio().
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 003b5c5719 ("block: Convert drivers
to immutable biovecs") broke dm-mirror due to dm-io breakage.
dm-io had three possible iterators (DM_IO_PAGE_LIST, DM_IO_BVEC,
DM_IO_VMA) that iterate over pages where the I/O should be performed.
The switch to immutable biovecs changed the DM_IO_BVEC iterator to
DM_IO_BIO. Before this change the iterator stored the pointer to a bio
vector in the dpages structure. The iterator incremented the pointer in
the dpages structure as it advanced over the pages. After the immutable
biovecs change, the DM_IO_BIO iterator stores a pointer to the bio in
the dpages structure and uses bio_advance to change the bio as it
advances.
The problem is that the function dispatch_io stores the content of the
dpages structure into the variable old_pages and restores it before
issuing I/O to each of the devices. Before the change, the statement
"*dp = old_pages;" restored the iterator to its starting position.
After the change, struct dpages holds a pointer to the bio, thus the
statement "*dp = old_pages;" doesn't restore the iterator.
Consequently, in the context of dm-mirror: only the first mirror leg is
written correctly, the kernel locks up when trying to write the other
mirror legs because the number of sectors to write in the where->count
variable doesn't match the number of sectors returned by the iterator.
This patch fixes the bug by partially reverting the original patch - it
changes the code so that struct dpages holds a pointer to the bio vector,
so that the statement "*dp = old_pages;" restores the iterator correctly.
The field "context_u" holds the offset from the beginning of the current
bio vector entry, just like the "bio->bi_iter.bi_bvec_done" field.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 905e51b ("dm thin: commit outstanding data every second")
introduced a periodic commit. This commit occurs regardless of whether
any thin devices have made changes.
Fix the periodic commit to check if any of a pool's thin devices have
changed using dm_pool_changed_this_transaction().
Reported-by: Alexander Larsson <alexl@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
When completing an overwrite bio, in overwrite_endio(), the associated
migration should not be added to the 'completed_migrations' until the
bio's fields are restored with dm_unhook_bio().
Otherwise, do_worker() can race to process 'completed_migrations' before
dm_unhook_bio() -- so the bio's bi_end_io is incorrect. This is
unlikely to cause any problems given the current code but should be
fixed on the basis of correctness.
Also, the cache's spinlock only needs to be held when manipulating the
'completed_migrations' list -- other changes don't need protection.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Commit c9d28d5d ("dm cache: promotion optimisation for writes")
incorrectly placed the 'hook_info' member in the writethrough-only
portion of the per_bio_data structure.
Given that the overwrite optimization may be used for writeback the
'hook_info' member must be placed above the 'cache' member of the
per_bio_data structure. Any members above 'cache' are available from
both writeback and writethrough modes' per_bio_data structure.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org # 3.13+
both tagged for -stable
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Merge tag 'md/3.14-fixes' of git://neil.brown.name/md
Pull md fixes from Neil Brown:
"Two bugfixes for md
both tagged for -stable"
* tag 'md/3.14-fixes' of git://neil.brown.name/md:
md/raid5: Fix CPU hotplug callback registration
md/raid1: restore ability for check and repair to fix read errors.
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
register_cpu_notifier(&foobar_cpu_notifier);
put_online_cpus();
This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).
Interestingly, the raid5 code can actually prevent double initialization and
hence can use the following simplified form of callback registration:
register_cpu_notifier(&foobar_cpu_notifier);
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
put_online_cpus();
A hotplug operation that occurs between registering the notifier and calling
get_online_cpus(), won't disrupt anything, because the code takes care to
perform the memory allocations only once.
So reorganize the code in raid5 this way to fix the deadlock with callback
registration.
Cc: linux-raid@vger.kernel.org
Cc: stable@vger.kernel.org (v2.6.32+)
Fixes: 36d1c6476b
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
[Srivatsa: Fixed the unregister_cpu_notifier() deadlock, added the
free_scratch_buffer() helper to condense code further and wrote the changelog.]
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This allows replying only to the requestor portid while still
supporting broadcasting. Pass 0 to portid for the previous behavior.
Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 30bc9b5387
md/raid1: fix bio handling problems in process_checks()
Move the bio_reset() to a point before where BIO_UPTODATE is checked,
so that check now always report that the bio is uptodate, even if it is not.
This causes process_check() to sometimes treat read-errors as
successful matches so the good data isn't written out.
This patch preserves the flag until it is needed.
Bug was introduced in 3.11, but backported to 3.10-stable (as it fixed
an even worse bug). So suitable for any -stable since 3.10.
Reported-and-tested-by: Michael Tokarev <mjt@tls.msk.ru>
Cc: stable@vger.kernel.org (3.10+)
Fixed: 30bc9b5387
Signed-off-by: NeilBrown <neilb@suse.de>
Pull block IO driver changes from Jens Axboe:
- bcache update from Kent Overstreet.
- two bcache fixes from Nicholas Swenson.
- cciss pci init error fix from Andrew.
- underflow fix in the parallel IDE pg_write code from Dan Carpenter.
I'm sure the 1 (or 0) users of that are now happy.
- two PCI related fixes for sx8 from Jingoo Han.
- floppy init fix for first block read from Jiri Kosina.
- pktcdvd error return miss fix from Julia Lawall.
- removal of IRQF_SHARED from the SEGA Dreamcast CD-ROM code from
Michael Opdenacker.
- comment typo fix for the loop driver from Olaf Hering.
- potential oops fix for null_blk from Raghavendra K T.
- two fixes from Sam Bradshaw (Micron) for the mtip32xx driver, fixing
an OOM problem and a problem with handling security locked conditions
* 'for-3.14/drivers' of git://git.kernel.dk/linux-block: (47 commits)
mg_disk: Spelling s/finised/finished/
null_blk: Null pointer deference problem in alloc_page_buffers
mtip32xx: Correctly handle security locked condition
mtip32xx: Make SGL container per-command to eliminate high order dma allocation
drivers/block/loop.c: fix comment typo in loop_config_discard
drivers/block/cciss.c:cciss_init_one(): use proper errnos
drivers/block/paride/pg.c: underflow bug in pg_write()
drivers/block/sx8.c: remove unnecessary pci_set_drvdata()
drivers/block/sx8.c: use module_pci_driver()
floppy: bail out in open() if drive is not responding to block0 read
bcache: Fix auxiliary search trees for key size > cacheline size
bcache: Don't return -EINTR when insert finished
bcache: Improve bucket_prio() calculation
bcache: Add bch_bkey_equal_header()
bcache: update bch_bkey_try_merge
bcache: Move insert_fixup() to btree_keys_ops
bcache: Convert sorting to btree_keys
bcache: Convert debug code to btree_keys
bcache: Convert btree_iter to struct btree_keys
bcache: Refactor bset_tree sysfs stats
...
Pull core block IO changes from Jens Axboe:
"The major piece in here is the immutable bio_ve series from Kent, the
rest is fairly minor. It was supposed to go in last round, but
various issues pushed it to this release instead. The pull request
contains:
- Various smaller blk-mq fixes from different folks. Nothing major
here, just minor fixes and cleanups.
- Fix for a memory leak in the error path in the block ioctl code
from Christian Engelmayer.
- Header export fix from CaiZhiyong.
- Finally the immutable biovec changes from Kent Overstreet. This
enables some nice future work on making arbitrarily sized bios
possible, and splitting more efficient. Related fixes to immutable
bio_vecs:
- dm-cache immutable fixup from Mike Snitzer.
- btrfs immutable fixup from Muthu Kumar.
- bio-integrity fix from Nic Bellinger, which is also going to stable"
* 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits)
xtensa: fixup simdisk driver to work with immutable bio_vecs
block/blk-mq-cpu.c: use hotcpu_notifier()
blk-mq: for_each_* macro correctness
block: Fix memory leak in rw_copy_check_uvector() handling
bio-integrity: Fix bio_integrity_verify segment start bug
block: remove unrelated header files and export symbol
blk-mq: uses page->list incorrectly
blk-mq: use __smp_call_function_single directly
btrfs: fix missing increment of bi_remaining
Revert "block: Warn and free bio if bi_end_io is not set"
block: Warn and free bio if bi_end_io is not set
blk-mq: fix initializing request's start time
block: blk-mq: don't export blk_mq_free_queue()
block: blk-mq: make blk_sync_queue support mq
block: blk-mq: support draining mq queue
dm cache: increment bi_remaining when bi_end_io is restored
block: fixup for generic bio chaining
block: Really silence spurious compiler warnings
block: Silence spurious compiler warnings
block: Kill bio_pair_split()
...
The BUG_ON at the end of __bch_btree_mark_key can be triggered due to
an integer overflow error:
BITMASK(GC_SECTORS_USED, struct bucket, gc_mark, 2, 13);
...
SET_GC_SECTORS_USED(g, min_t(unsigned,
GC_SECTORS_USED(g) + KEY_SIZE(k),
(1 << 14) - 1));
BUG_ON(!GC_SECTORS_USED(g));
In bcache.h, the SECTORS_USED bitfield is defined to be 13 bits wide.
While the SET_ code tries to ensure that the field doesn't overflow by
clamping it to (1<<14)-1 == 16383, this is incorrect because 16383
requires 14 bits. Therefore, if GC_SECTORS_USED() + KEY_SIZE() =
8192, the SET_ statement tries to store 8192 into a 13-bit field. In
a 13-bit field, 8192 becomes zero, thus triggering the BUG_ON.
Therefore, create a field width constant and a max value constant, and
use those to create the bitfield and check the inputs to
SET_GC_SECTORS_USED. Arguably the BITMASK() template ought to have
BUG_ON checks for too-large values, but that's a separate patch.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
All bug fixes, two tagged for -stable.
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Merge tag 'md/3.14' of git://neil.brown.name/md
Pull md updates from Neil Brown:
"All bug fixes, two tagged for -stable"
* tag 'md/3.14' of git://neil.brown.name/md:
md/raid5: close recently introduced race in stripe_head management.
md/raid5: fix long-standing problem with bitmap handling on write failure.
md: check command validity early in md_ioctl().
md: ensure metadata is writen after raid level change.
md/raid10: avoid fullsync when not necessary.
md: allow a partially recovered device to be hot-added to an array.
md: Change handling of save_raid_disk and metadata update during recovery.
A lot of attention was paid to improving the thin-provisioning target's
handling of metadata operation failures and running out of space. A new
'error_if_no_space' feature was added to allow users to error IOs rather
than queue them when either the data or metadata space is exhausted.
Additional fixes/features include:
- a few fixes to properly support thin metadata device resizing
- a solution for reliably waiting for a DM device's embedded kobject to
be released before destroying the device
- old dm-snapshot is updated to use the dm-bufio interface to take
advantage of readahead capabilities that improve snapshot activation
- new dm-cache target tunables to control how quickly data is promoted
to the cache (fast) device
- improved write efficiency of cluster mirror target by combining
userspace flush and mark requests
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Merge tag 'dm-3.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device-mapper changes from Mike Snitzer:
"A lot of attention was paid to improving the thin-provisioning
target's handling of metadata operation failures and running out of
space. A new 'error_if_no_space' feature was added to allow users to
error IOs rather than queue them when either the data or metadata
space is exhausted.
Additional fixes/features include:
- a few fixes to properly support thin metadata device resizing
- a solution for reliably waiting for a DM device's embedded kobject
to be released before destroying the device
- old dm-snapshot is updated to use the dm-bufio interface to take
advantage of readahead capabilities that improve snapshot
activation
- new dm-cache target tunables to control how quickly data is
promoted to the cache (fast) device
- improved write efficiency of cluster mirror target by combining
userspace flush and mark requests"
* tag 'dm-3.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits)
dm log userspace: allow mark requests to piggyback on flush requests
dm space map metadata: fix bug in resizing of thin metadata
dm cache: add policy name to status output
dm thin: fix pool feature parsing
dm sysfs: fix a module unload race
dm snapshot: use dm-bufio prefetch
dm snapshot: use dm-bufio
dm snapshot: prepare for switch to using dm-bufio
dm snapshot: use GFP_KERNEL when initializing exceptions
dm cache: add block sizes and total cache blocks to status output
dm btree: add dm_btree_find_lowest_key
dm space map metadata: fix extending the space map
dm space map common: make sure new space is used during extend
dm: wait until embedded kobject is released before destroying a device
dm: remove pointless kobject comparison in dm_get_from_kobject
dm snapshot: call destroy_work_on_stack() to pair with INIT_WORK_ONSTACK()
dm cache policy mq: introduce three promotion threshold tunables
dm cache policy mq: use list_del_init instead of list_del + INIT_LIST_HEAD
dm thin: fix set_pool_mode exposed pool operation races
dm thin: eliminate the no_free_space flag
...
In the cluster evironment, cluster write has poor performance because
userspace_flush() has to contact a userspace program (cmirrord) for
clear/mark/flush requests. But both mark and flush requests require
cmirrord to communicate the message to all the cluster nodes for each
flush call. This behaviour is really slow.
To address this we now merge mark and flush requests together to reduce
the kernel-userspace-kernel time. We allow a new directive,
"integrated_flush" that can be used to instruct the kernel log code to
combine flush and mark requests when directed by userspace. If not
directed by userspace (due to an older version of the userspace code
perhaps), the kernel will function as it did previously - preserving
backwards compatibility. Additionally, flush requests are performed
lazily when only clear requests exist.
Signed-off-by: Dongmao Zhang <dmzhang@suse.com>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull cgroup updates from Tejun Heo:
"The bulk of changes are cleanups and preparations for the upcoming
kernfs conversion.
- cgroup_event mechanism which is and will be used only by memcg is
moved to memcg.
- pidlist handling is updated so that it can be served by seq_file.
Also, the list is not sorted if sane_behavior. cgroup
documentation explicitly states that the file is not sorted but it
has been for quite some time.
- All cgroup file handling now happens on top of seq_file. This is
to prepare for kernfs conversion. In addition, all operations are
restructured so that they map 1-1 to kernfs operations.
- Other cleanups and low-pri fixes"
* 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (40 commits)
cgroup: trivial style updates
cgroup: remove stray references to css_id
doc: cgroups: Fix typo in doc/cgroups
cgroup: fix fail path in cgroup_load_subsys()
cgroup: fix missing unlock on error in cgroup_load_subsys()
cgroup: remove for_each_root_subsys()
cgroup: implement for_each_css()
cgroup: factor out cgroup_subsys_state creation into create_css()
cgroup: combine css handling loops in cgroup_create()
cgroup: reorder operations in cgroup_create()
cgroup: make for_each_subsys() useable under cgroup_root_mutex
cgroup: css iterations and css_from_dir() are safe under cgroup_mutex
cgroup: unify pidlist and other file handling
cgroup: replace cftype->read_seq_string() with cftype->seq_show()
cgroup: attach cgroup_open_file to all cgroup files
cgroup: generalize cgroup_pidlist_open_file
cgroup: unify read path so that seq_file is always used
cgroup: unify cgroup_write_X64() and cgroup_write_string()
cgroup: remove cftype->read(), ->read_map() and ->write()
hugetlb_cgroup: convert away from cftype->read()
...
As release_stripe and __release_stripe decrement ->count and then
manipulate ->lru both under ->device_lock, it is important that
get_active_stripe() increments ->count and clears ->lru also under
->device_lock.
However we currently list_del_init ->lru under the lock, but increment
the ->count outside the lock. This can lead to races and list
corruption.
So move the atomic_inc(&sh->count) up inside the ->device_lock
protected region.
Note that we still increment ->count without device lock in the case
where get_free_stripe() was called, and in fact don't take
->device_lock at all in that path.
This is safe because if the stripe_head can be found by
get_free_stripe, then the hash lock assures us the no-one else could
possibly be calling release_stripe() at the same time.
Fixes: 566c09c534
Cc: stable@vger.kernel.org (3.13)
Reported-and-tested-by: Ian Kumlien <ian.kumlien@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This bug was introduced in commit 7e664b3dec ("dm space map metadata:
fix extending the space map").
When extending a dm-thin metadata volume we:
- Switch the space map into a simple bootstrap mode, which allocates
all space linearly from the newly added space.
- Add new bitmap entries for the new space
- Increment the reference counts for those newly allocated bitmap
entries
- Commit changes to disk
- Switch back out of bootstrap mode.
But, the disk commit may allocate space itself, if so this fact will be
lost when switching out of bootstrap mode.
The bug exhibited itself as an error when the bitmap_root, with an
erroneous ref count of 0, was subsequently decremented as part of a
later disk commit. This would cause the disk commit to fail, and thinp
to enter read_only mode. The metadata was not damaged (thin_check
passed).
The fix is to put the increments + commit into a loop, running until
the commit has not allocated extra space. In practise this loop only
runs twice.
With this fix the following device mapper testsuite test passes:
dmtest run --suite thin-provisioning -n thin_remove_works_after_resize
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # depends on commit 7e664b3dec
Here's the big driver core and sysfs patch set for 3.14-rc1.
There's a lot of work here moving sysfs logic out into a "kernfs" to
allow other subsystems to also have a virtual filesystem with the same
attributes of sysfs (handle device disconnect, dynamic creation /
removal as needed / unneeded, etc. This is primarily being done for
the cgroups filesystem, but the goal is to also move debugfs to it when
it is ready, solving all of the known issues in that filesystem as well.
The code isn't completed yet, but all should be stable now (there is a
big section that was reverted due to problems found when testing.)
There's also some other smaller fixes, and a driver core addition that
allows for a "collection" of objects, that the DRM people will be using
soon (it's in this tree to make merges after -rc1 easier.)
All of this has been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core / sysfs patches from Greg KH:
"Here's the big driver core and sysfs patch set for 3.14-rc1.
There's a lot of work here moving sysfs logic out into a "kernfs" to
allow other subsystems to also have a virtual filesystem with the same
attributes of sysfs (handle device disconnect, dynamic creation /
removal as needed / unneeded, etc)
This is primarily being done for the cgroups filesystem, but the goal
is to also move debugfs to it when it is ready, solving all of the
known issues in that filesystem as well. The code isn't completed
yet, but all should be stable now (there is a big section that was
reverted due to problems found when testing)
There's also some other smaller fixes, and a driver core addition that
allows for a "collection" of objects, that the DRM people will be
using soon (it's in this tree to make merges after -rc1 easier)
All of this has been in linux-next with no reported issues"
* tag 'driver-core-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (113 commits)
kernfs: associate a new kernfs_node with its parent on creation
kernfs: add struct dentry declaration in kernfs.h
kernfs: fix get_active failure handling in kernfs_seq_*()
Revert "kernfs: fix get_active failure handling in kernfs_seq_*()"
Revert "kernfs: replace kernfs_node->u.completion with kernfs_root->deactivate_waitq"
Revert "kernfs: remove KERNFS_ACTIVE_REF and add kernfs_lockdep()"
Revert "kernfs: remove KERNFS_REMOVED"
Revert "kernfs: restructure removal path to fix possible premature return"
Revert "kernfs: invoke kernfs_unmap_bin_file() directly from __kernfs_remove()"
Revert "kernfs: remove kernfs_addrm_cxt"
Revert "kernfs: make kernfs_get_active() block if the node is deactivated but not removed"
Revert "kernfs: implement kernfs_{de|re}activate[_self]()"
Revert "kernfs, sysfs, driver-core: implement kernfs_remove_self() and its wrappers"
Revert "pci: use device_remove_file_self() instead of device_schedule_callback()"
Revert "scsi: use device_remove_file_self() instead of device_schedule_callback()"
Revert "s390: use device_remove_file_self() instead of device_schedule_callback()"
Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()"
Revert "kernfs: remove unnecessary NULL check in __kernfs_remove()"
kernfs: remove unnecessary NULL check in __kernfs_remove()
drivers/base: provide an infrastructure for componentised subsystems
...
The cache's policy may have been established using the "default" alias,
which is currently the "mq" policy but the default policy may change in
the future. It is useful to know exactly which policy is being used.
Add a 'real' member to the dm_cache_policy_type structure and have the
"default" dm_cache_policy_type point to the real "mq"
dm_cache_policy_type. Update dm_cache_policy_get_name() to check if
real is set, if so report the name of the real policy (not the alias).
Requested-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 787a996cb2 ("dm thin: add error_if_no_space feature")
mistakenly forgot to increase the number of feature args supported.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Before a write starts we set a bit in the write-intent bitmap.
When the write completes we clear that bit if the write was successful
to all devices. However if the write wasn't fully successful we
should not clear the bit. If the faulty drive is subsequently
re-added, the fact that the bit is still set ensure that we will
re-write the data that is missing.
This logic is mediated by the STRIPE_DEGRADED flag - we only clear the
bitmap bit when this flag is not set.
Currently we correctly set the flag if a write starts when some
devices are failed or missing. But we do *not* set the flag if some
device failed during the write attempt.
This is wrong and can result in clearing the bit inappropriately.
So: set the flag when a write fails.
This bug has been present since bitmaps were introduces, so the fix is
suitable for any -stable kernel.
Reported-by: Ethan Wilson <ethan.wilson@shiftmail.org>
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
