Commit Graph

6167 Commits

Author SHA1 Message Date
Yang Yingliang
3fd53533a8 dm crypt: use crypt_integrity_aead() helper
Replace test_bit(CRYPT_MODE_INTEGRITY_AEAD, XXX) with
crypt_integrity_aead().

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-03-24 11:17:33 -04:00
Christoph Hellwig
74cc979c3c block: cleanup how md_autodetect_dev is called
Add a new include/linux/raid/detect.h header to declare the
md_autodetect_dev prototype which can be shared between md and
the partition code.  Then use IS_BUILTIN to call it instead of the
ifdef magic.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-24 07:57:08 -06:00
Christoph Hellwig
ea3edd4dc2 block: remove __bdevname
There is no good reason for __bdevname to exist.  Just open code
printing the string in the callers.  For three of them the format
string can be trivially merged into existing printk statements,
and in init/do_mounts.c we can at least do the scnprintf once at
the start of the function, and unconditional of CONFIG_BLOCK to
make the output for tiny configfs a little more helpful.

Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-24 07:57:07 -06:00
Coly Li
eb9b6666d6 bcache: optimize barrier usage for atomic operations
The idea of this patch is from Davidlohr Bueso, he posts a patch
for bcache to optimize barrier usage for read-modify-write atomic
bitops. Indeed such optimization can also apply on other locations
where smp_mb() is used before or after an atomic operation.

This patch replaces smp_mb() with smp_mb__before_atomic() or
smp_mb__after_atomic() in btree.c and writeback.c,  where it is used
to synchronize memory cache just earlier on other cores. Although
the locations are not on hot code path, it is always not bad to mkae
things a little better.

Signed-off-by: Coly Li <colyli@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22 10:06:57 -06:00
Davidlohr Bueso
b004aa867c bcache: optimize barrier usage for Rmw atomic bitops
We can avoid the unnecessary barrier on non LL/SC architectures,
such as x86. Instead, use the smp_mb__after_atomic().

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22 10:06:57 -06:00
Takashi Iwai
9876e38609 bcache: Use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22 10:06:57 -06:00
Coly Li
b144e45fc5 bcache: make bch_sectors_dirty_init() to be multithreaded
When attaching a cached device (a.k.a backing device) to a cache
device, bch_sectors_dirty_init() is called to count dirty sectors
and stripes (see what bcache_dev_sectors_dirty_add() does) on the
cache device.

The counting is done by a single thread recursive function
bch_btree_map_keys() to iterate all the bcache btree nodes.
If the btree has huge number of nodes, bch_sectors_dirty_init() will
take quite long time. In my testing, if the registering cache set has
a existed UUID which matches a already registered cached device, the
automatical attachment during the registration may take more than
55 minutes. This is too long for waiting the bcache to work in real
deployment.

Fortunately when bch_sectors_dirty_init() is called, no other thread
will access the btree yet, it is safe to do a read-only parallelized
dirty sectors counting by multiple threads.

This patch tries to create multiple threads, and each thread tries to
one-by-one count dirty sectors from the sub-tree indexed by a root
node key which the thread fetched. After the sub-tree is counted, the
counting thread will continue to fetch another root node key, until
the fetched key is NULL. How many threads in parallel depends on
the number of keys from the btree root node, and the number of online
CPU core. The thread number will be the less number but no more than
BCH_DIRTY_INIT_THRD_MAX. If there are only 2 keys in root node, it
can only be 2x times faster by this patch. But if there are 10 keys
in the root node, with this patch it can be 10x times faster.

Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22 10:06:57 -06:00
Coly Li
8e7102273f bcache: make bch_btree_check() to be multithreaded
When registering a cache device, bch_btree_check() is called to check
all btree nodes, to make sure the btree is consistent and not
corrupted.

bch_btree_check() is recursively executed in a single thread, when there
are a lot of data cached and the btree is huge, it may take very long
time to check all the btree nodes. In my testing, I observed it took
around 50 minutes to finish bch_btree_check().

When checking the bcache btree nodes, the cache set is not running yet,
and indeed the whole tree is in read-only state, it is safe to create
multiple threads to check the btree in parallel.

This patch tries to create multiple threads, and each thread tries to
one-by-one check the sub-tree indexed by a key from the btree root node.
The parallel thread number depends on how many keys in the btree root
node. At most BCH_BTR_CHKTHREAD_MAX (64) threads can be created, but in
practice is should be min(cpu-number/2, root-node-keys-number).

Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22 10:06:57 -06:00
Coly Li
feac1a70b8 bcache: add bcache_ prefix to btree_root() and btree() macros
This patch changes macro btree_root() and btree() to bcache_btree_root()
and bcache_btree(), to avoid potential generic name clash in future.

NOTE: for product kernel maintainers, this patch can be skipped if
you feel the rename stuffs introduce inconvenince to patch backport.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22 10:06:57 -06:00
Coly Li
253a99d95d bcache: move macro btree() and btree_root() into btree.h
In order to accelerate bcache registration speed, the macro btree()
and btree_root() will be referenced out of btree.c. This patch moves
them from btree.c into btree.h with other relative function declaration
in btree.h, for the following changes.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-22 10:06:57 -06:00
Guoqing Jiang
6b40bec3b1 md: check arrays is suspended in mddev_detach before call quiesce operations
Don't call quiesce(1) and quiesce(0) if array is already suspended,
otherwise in level_store, the array is writable after mddev_detach
in below part though the intention is to make array writable after
resume.

	mddev_suspend(mddev);
	mddev_detach(mddev);
	...
	mddev_resume(mddev);

And it also causes calltrace as follows in [1].

[48005.653834] WARNING: CPU: 1 PID: 45380 at kernel/kthread.c:510 kthread_park+0x77/0x90
[...]
[48005.653976] CPU: 1 PID: 45380 Comm: mdadm Tainted: G           OE     5.4.10-arch1-1 #1
[48005.653979] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./J4105-ITX, BIOS P1.40 08/06/2018
[48005.653984] RIP: 0010:kthread_park+0x77/0x90
[48005.654015] Call Trace:
[48005.654039]  r5l_quiesce+0x3c/0x70 [raid456]
[48005.654052]  raid5_quiesce+0x228/0x2e0 [raid456]
[48005.654073]  mddev_detach+0x30/0x70 [md_mod]
[48005.654090]  level_store+0x202/0x670 [md_mod]
[48005.654099]  ? security_capable+0x40/0x60
[48005.654114]  md_attr_store+0x7b/0xc0 [md_mod]
[48005.654123]  kernfs_fop_write+0xce/0x1b0
[48005.654132]  vfs_write+0xb6/0x1a0
[48005.654138]  ksys_write+0x67/0xe0
[48005.654146]  do_syscall_64+0x4e/0x140
[48005.654155]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[48005.654161] RIP: 0033:0x7fa0c8737497

[1]: https://bugzilla.kernel.org/show_bug.cgi?id=206161

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-03-17 10:53:07 -07:00
Linus Torvalds
5dfcc13902 block-5.6-2020-03-07
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl5j8hwQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpnjID/4/XVrqtVNUzVoVOtkOyxyesBrJVMHEQEpJ
 PZssv835IStw0ENhxQJfGjPaIFc9Ff6PMkeN5KRAlMoEc+NkrJShF3owGf+6Bps7
 rxpblPxaw+CJFa31YBDZVjMCvbVkDm40G5SsJh+xzdIjlWz7MppkkMPdrErPwY8V
 0vnrIc+mKBKfBMZTwVkycYtp17LVgfXguledoWzxM1y47IW5UasKh8jdzhbu8Hvt
 zztdQrigUdb+9XnLGCZIY0JQOyrhJ5zQpZ40FzbvxdYrQZXOoYT8L7iFu/z0Wi7K
 p3a+G+B4WowtLYW78me4Uut5RrHq2XOehSypfujanQlpgXPGjS3TdHT3an2T8XPQ
 NyGsZsn/eLm3btNbhGUd8vqpQy5EmWhqmwvYk9tFAoSFLiLcvCC624b/TCYPL+gk
 3ZiI7mXBMjHnUZ0J/RF6kZWTAZDvr/tE7UZt1f8r1eEr8VDzCNp5Pst+HCVIguYD
 g9eWF8oH6wYoj39UKf1k+vW2GjXGFsnfivObaxhyz03sAPXK2wQlzAe/4jZ24XNr
 TRtOXh97c3CbLAwdUHehlzzdR3U7h0n2KsmrTC5AGmLABmR79s7BJ0+pexuZituO
 LwU8+gpf7AugHTrLg1eNXAmBHW44I1ticXYiWcT4iSPn99kNIhlW+Jb1iTGoiu7n
 nXyS3b5SCw==
 =xwKl
 -----END PGP SIGNATURE-----

Merge tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Here are a few fixes that should go into this release. This contains:

   - Revert of a bad bcache patch from this merge window

   - Removed unused function (Daniel)

   - Fixup for the blktrace fix from Jan from this release (Cengiz)

   - Fix of deeper level bfqq overwrite in BFQ (Carlo)"

* tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block:
  block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group()
  blktrace: fix dereference after null check
  Revert "bcache: ignore pending signals when creating gc and allocator thread"
  block: Remove used kblockd_schedule_work_on()
2020-03-07 14:14:38 -06:00
Linus Torvalds
776e49e8dd - Fix request-based DM's congestion_fn and actually wire it up to the
bdi.
 
 - Extend dm-bio-record to track additional struct bio members needed
   by DM integrity target.
 
 - Fix DM core to properly advertise that a device is suspended during
   unload (between the presuspend and postsuspend hooks).  This change
   is a prereq for related DM integrity and DM writecache fixes.  It
   elevates DM integrity's 'suspending' state tracking to DM core.
 
 - Four stable fixes for DM integrity target.
 
 - Fix crash in DM cache target due to incorrect work item cancelling.
 
 - Fix DM thin metadata lockdep warning that was introduced during 5.6
   merge window.
 
 - Fix DM zoned target's chunk work refcounting that regressed during
   recent conversion to refcount_t.
 
 - Bump the minor version for DM core and all target versions that have
   seen interface changes or important fixes during the 5.6 cycle.
 -----BEGIN PGP SIGNATURE-----
 
 iQFHBAABCAAxFiEEJfWUX4UqZ4x1O2wixSPxCi2dA1oFAl5fwPgTHHNuaXR6ZXJA
 cmVkaGF0LmNvbQAKCRDFI/EKLZ0DWnUJB/9+36J0Y3HYdUIKM8P5CBH0tdkMqSo4
 BFm3Og4Xo1GA5xodNptgD+QoLXy3VWkekUsLvaLgOlPq7haPvHkME20vUMuO1l46
 QMNR2VXciYGgV0+CFlpXL2oMr0ZEc1hkt7ZpzYaw1OIk6Mo0tEEDrSo0rvmXafPf
 W4veTWRL4HfN8fy3NpQNJ4xBQs4Iw4VC20FPFIOvzA1EGk7VGGaP1mGKmOnjxo/O
 o3lEH8NpQgwxwST7d4T6DPdeu3aTifnjdY8/h8mFGpQnxOiZ/wZkheKWwTCNE8r9
 oeVY07qVxNAHyC8G/SmAL5KnC6En1hq5jA2M4xh9guUI2k8YbON571n+
 =iAS0
 -----END PGP SIGNATURE-----

Merge tag 'for-5.6/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Fix request-based DM's congestion_fn and actually wire it up to the
   bdi.

 - Extend dm-bio-record to track additional struct bio members needed by
   DM integrity target.

 - Fix DM core to properly advertise that a device is suspended during
   unload (between the presuspend and postsuspend hooks). This change is
   a prereq for related DM integrity and DM writecache fixes. It
   elevates DM integrity's 'suspending' state tracking to DM core.

 - Four stable fixes for DM integrity target.

 - Fix crash in DM cache target due to incorrect work item cancelling.

 - Fix DM thin metadata lockdep warning that was introduced during 5.6
   merge window.

 - Fix DM zoned target's chunk work refcounting that regressed during
   recent conversion to refcount_t.

 - Bump the minor version for DM core and all target versions that have
   seen interface changes or important fixes during the 5.6 cycle.

* tag 'for-5.6/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm: bump version of core and various targets
  dm: fix congested_fn for request-based device
  dm integrity: use dm_bio_record and dm_bio_restore
  dm bio record: save/restore bi_end_io and bi_integrity
  dm zoned: Fix reference counter initial value of chunk works
  dm writecache: verify watermark during resume
  dm: report suspended device during destroy
  dm thin metadata: fix lockdep complaint
  dm cache: fix a crash due to incorrect work item cancelling
  dm integrity: fix invalid table returned due to argument count mismatch
  dm integrity: fix a deadlock due to offloading to an incorrect workqueue
  dm integrity: fix recalculation when moving from journal mode to bitmap mode
2020-03-04 13:02:45 -06:00
Mike Snitzer
636be4241b dm: bump version of core and various targets
Changes made during the 5.6 cycle warrant bumping the version number
for DM core and the targets modified by this commit.

It should be noted that dm-thin, dm-crypt and dm-raid already had
their target version bumped during the 5.6 merge window.

Signed-off-by; Mike Snitzer <snitzer@redhat.com>
2020-03-03 11:10:21 -05:00
Hou Tao
974f51e863 dm: fix congested_fn for request-based device
We neither assign congested_fn for requested-based blk-mq device nor
implement it correctly. So fix both.

Also, remove incorrect comment from dm_init_normal_md_queue and rename
it to dm_init_congested_fn.

Fixes: 4aa9c692e0 ("bdi: separate out congested state into a separate struct")
Cc: stable@vger.kernel.org
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-03-03 11:10:20 -05:00
Mike Snitzer
248aa2645a dm integrity: use dm_bio_record and dm_bio_restore
In cases where dec_in_flight() has to requeue the integrity_bio_wait
work to transfer the rest of the data, the bio's __bi_remaining might
already have been decremented to 0, e.g.: if bio passed to underlying
data device was split via blk_queue_split().

Use dm_bio_{record,restore} rather than effectively open-coding them in
dm-integrity -- these methods now manage __bi_remaining too.

Depends-on: f7f0b057a9c1 ("dm bio record: save/restore bi_end_io and bi_integrity")
Reported-by: Daniel Glöckner <dg@emlix.com>
Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-03-03 10:02:47 -05:00
Mike Snitzer
1b17159e52 dm bio record: save/restore bi_end_io and bi_integrity
Also, save/restore __bi_remaining in case the bio was used in a
BIO_CHAIN (e.g. due to blk_queue_split).

Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-03-03 10:02:46 -05:00
Jens Axboe
764b53b26c Revert "bcache: ignore pending signals when creating gc and allocator thread"
This reverts commit 0b96da639a.

We can't just go flushing random signals, under the assumption that the
OOM killer will just do something else. It's not safe from the OOM
perspective, and it could also cause other signals to get randomly lost.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-02 20:01:32 -07:00
Shin'ichiro Kawasaki
ee63634bae dm zoned: Fix reference counter initial value of chunk works
Dm-zoned initializes reference counters of new chunk works with zero
value and refcount_inc() is called to increment the counter. However, the
refcount_inc() function handles the addition to zero value as an error
and triggers the warning as follows:

refcount_t: addition on 0; use-after-free.
WARNING: CPU: 7 PID: 1506 at lib/refcount.c:25 refcount_warn_saturate+0x68/0xf0
...
CPU: 7 PID: 1506 Comm: systemd-udevd Not tainted 5.4.0+ #134
...
Call Trace:
 dmz_map+0x2d2/0x350 [dm_zoned]
 __map_bio+0x42/0x1a0
 __split_and_process_non_flush+0x14a/0x1b0
 __split_and_process_bio+0x83/0x240
 ? kmem_cache_alloc+0x165/0x220
 dm_process_bio+0x90/0x230
 ? generic_make_request_checks+0x2e7/0x680
 dm_make_request+0x3e/0xb0
 generic_make_request+0xcf/0x320
 ? memcg_drain_all_list_lrus+0x1c0/0x1c0
 submit_bio+0x3c/0x160
 ? guard_bio_eod+0x2c/0x130
 mpage_readpages+0x182/0x1d0
 ? bdev_evict_inode+0xf0/0xf0
 read_pages+0x6b/0x1b0
 __do_page_cache_readahead+0x1ba/0x1d0
 force_page_cache_readahead+0x93/0x100
 generic_file_read_iter+0x83a/0xe40
 ? __seccomp_filter+0x7b/0x670
 new_sync_read+0x12a/0x1c0
 vfs_read+0x9d/0x150
 ksys_read+0x5f/0xe0
 do_syscall_64+0x5b/0x180
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
...

After this warning, following refcount API calls for the counter all fail
to change the counter value.

Fix this by setting the initial reference counter value not zero but one
for the new chunk works. Instead, do not call refcount_inc() via
dmz_get_chunk_work() for the new chunks works.

The failure was observed with linux version 5.4 with CONFIG_REFCOUNT_FULL
enabled. Refcount rework was merged to linux version 5.5 by the
commit 168829ad09 ("Merge branch 'locking-core-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip"). After this
commit, CONFIG_REFCOUNT_FULL was removed and the failure was observed
regardless of kernel configuration.

Linux version 4.20 merged the commit 092b564876 ("dm zoned: target: use
refcount_t for dm zoned reference counters"). Before this commit, dm
zoned used atomic_t APIs which does not check addition to zero, then this
fix is not necessary.

Fixes: 092b564876 ("dm zoned: target: use refcount_t for dm zoned reference counters")
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-27 16:44:25 -05:00
Mikulas Patocka
41c526c5af dm writecache: verify watermark during resume
Verify the watermark upon resume - so that if the target is reloaded
with lower watermark, it will start the cleanup process immediately.

Fixes: 48debafe4f ("dm: add writecache target")
Cc: stable@vger.kernel.org # 4.18+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-27 16:44:24 -05:00
Mikulas Patocka
adc0daad36 dm: report suspended device during destroy
The function dm_suspended returns true if the target is suspended.
However, when the target is being suspended during unload, it returns
false.

An example where this is a problem: the test "!dm_suspended(wc->ti)" in
writecache_writeback is not sufficient, because dm_suspended returns
zero while writecache_suspend is in progress.  As is, without an
enhanced dm_suspended, simply switching from flush_workqueue to
drain_workqueue still emits warnings:
workqueue writecache-writeback: drain_workqueue() isn't complete after 10 tries
workqueue writecache-writeback: drain_workqueue() isn't complete after 100 tries
workqueue writecache-writeback: drain_workqueue() isn't complete after 200 tries
workqueue writecache-writeback: drain_workqueue() isn't complete after 300 tries
workqueue writecache-writeback: drain_workqueue() isn't complete after 400 tries

writecache_suspend calls flush_workqueue(wc->writeback_wq) - this function
flushes the current work. However, the workqueue may re-queue itself and
flush_workqueue doesn't wait for re-queued works to finish. Because of
this - the function writecache_writeback continues execution after the
device was suspended and then concurrently with writecache_dtr, causing
a crash in writecache_writeback.

We must use drain_workqueue - that waits until the work and all re-queued
works finish.

As a prereq for switching to drain_workqueue, this commit fixes
dm_suspended to return true after the presuspend hook and before the
postsuspend hook - just like during a normal suspend. It allows
simplifying the dm-integrity and dm-writecache targets so that they
don't have to maintain suspended flags on their own.

With this change use of drain_workqueue() can be used effectively.  This
change was tested with the lvm2 testsuite and cryptsetup testsuite and
the are no regressions.

Fixes: 48debafe4f ("dm: add writecache target")
Cc: stable@vger.kernel.org # 4.18+
Reported-by: Corey Marthaler <cmarthal@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-27 16:40:58 -05:00
Theodore Ts'o
3918e0667b dm thin metadata: fix lockdep complaint
[ 3934.173244] ======================================================
[ 3934.179572] WARNING: possible circular locking dependency detected
[ 3934.185884] 5.4.21-xfstests #1 Not tainted
[ 3934.190151] ------------------------------------------------------
[ 3934.196673] dmsetup/8897 is trying to acquire lock:
[ 3934.201688] ffffffffbce82b18 (shrinker_rwsem){++++}, at: unregister_shrinker+0x22/0x80
[ 3934.210268]
               but task is already holding lock:
[ 3934.216489] ffff92a10cc5e1d0 (&pmd->root_lock){++++}, at: dm_pool_metadata_close+0xba/0x120
[ 3934.225083]
               which lock already depends on the new lock.

[ 3934.564165] Chain exists of:
                 shrinker_rwsem --> &journal->j_checkpoint_mutex --> &pmd->root_lock

For a more detailed lockdep report, please see:

	https://lore.kernel.org/r/20200220234519.GA620489@mit.edu

We shouldn't need to hold the lock while are just tearing down and
freeing the whole metadata pool structure.

Fixes: 44d8ebf436 ("dm thin metadata: use pool locking at end of dm_pool_metadata_close")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-27 12:00:53 -05:00
Mikulas Patocka
7cdf6a0aae dm cache: fix a crash due to incorrect work item cancelling
The crash can be reproduced by running the lvm2 testsuite test
lvconvert-thin-external-cache.sh for several minutes, e.g.:
  while :; do make check T=shell/lvconvert-thin-external-cache.sh; done

The crash happens in this call chain:
do_waker -> policy_tick -> smq_tick -> end_hotspot_period -> clear_bitset
-> memset -> __memset -- which accesses an invalid pointer in the vmalloc
area.

The work entry on the workqueue is executed even after the bitmap was
freed. The problem is that cancel_delayed_work doesn't wait for the
running work item to finish, so the work item can continue running and
re-submitting itself even after cache_postsuspend. In order to make sure
that the work item won't be running, we must use cancel_delayed_work_sync.

Also, change flush_workqueue to drain_workqueue, so that if some work item
submits itself or another work item, we are properly waiting for both of
them.

Fixes: c6b4fcbad0 ("dm: add cache target")
Cc: stable@vger.kernel.org # v3.9
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-27 12:00:52 -05:00
Mikulas Patocka
7fc2e47f40 dm integrity: fix invalid table returned due to argument count mismatch
If the flag SB_FLAG_RECALCULATE is present in the superblock, but it was
not specified on the command line (i.e. ic->recalculate_flag is false),
dm-integrity would return invalid table line - the reported number of
arguments would not match the real number.

Fixes: 468dfca38b ("dm integrity: add a bitmap mode")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Ondrej Kozina <okozina@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-25 12:06:08 -05:00
Mikulas Patocka
53770f0ec5 dm integrity: fix a deadlock due to offloading to an incorrect workqueue
If we need to perform synchronous I/O in dm_integrity_map_continue(),
we must make sure that we are not in the map function - in order to
avoid the deadlock due to bio queuing in generic_make_request. To
avoid the deadlock, we offload the request to metadata_wq.

However, metadata_wq also processes metadata updates for write requests.
If there are too many requests that get offloaded to metadata_wq at the
beginning of dm_integrity_map_continue, the workqueue metadata_wq
becomes clogged and the system is incapable of processing any metadata
updates.

This causes a deadlock because all the requests that need to do metadata
updates wait for metadata_wq to proceed and metadata_wq waits inside
wait_and_add_new_range until some existing request releases its range
lock (which doesn't happen because the range lock is released after
metadata update).

In order to fix the deadlock, we create a new workqueue offload_wq and
offload requests to it - so that processing of offload_wq is independent
from processing of metadata_wq.

Fixes: 7eada909bf ("dm: add integrity target")
Cc: stable@vger.kernel.org # v4.12+
Reported-by: Heinz Mauelshagen <heinzm@redhat.com>
Tested-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-25 12:06:07 -05:00
Mikulas Patocka
d5bdf66108 dm integrity: fix recalculation when moving from journal mode to bitmap mode
If we resume a device in bitmap mode and the on-disk format is in journal
mode, we must recalculate anything above ic->sb->recalc_sector. Otherwise,
there would be non-recalculated blocks which would cause I/O errors.

Fixes: 468dfca38b ("dm integrity: add a bitmap mode")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-02-25 12:06:06 -05:00
Linus Torvalds
e29c6a13dd block-5.6-2020-02-16
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl5JdgMQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpg6eEAC7/f/ATcrAbQUjx8vsNS0UgtYB1LPdgga6
 7MwYKnrzdWWZICOxOgRR4W//wXFRf3vUtmzF5MgGpzJzgeKuyv09Vz1PLcxkAcny
 hu9NTQWu6xtxEGiYlfaSW7EQBRdb1876kzOyV+hTrkvQZ9CXcIAQHwjQPKqjqdlb
 /j3l5GSjyO0npvsCqIWrsNoeSwfDOhFi+I3hHZutt3T0fPnjo6DGtXN7m4jhWzW/
 U3S4yHxmLVDKzorDDMoTV2D8UGrpjQmRXD78QOpOJKO7ngr9OT69dcMH6TnDkUDb
 a7O5l5k5DB+0QOQWk5IHJpMRRp3NdVHgnZhTJZaho8kuKoTLwteJFAprJTzHuuvC
 BkTBYf1Ref9KT5YfaUcWI+rmq32LgRq8rRaJBF+vqGcOwJw6WRIuygGyZ8eJMItb
 oOhsFEOKKDAILncxg5C61v2Sh4g+/YpQojyVCzJSb7UNjOMtDPgjEp2dDSa+/p84
 detTqmlt5ZPYHFvsp/EHuGB6ohscsvKzZk+wlQvj4Wq3T7agSp9uljfiTmUdsmWn
 69fs66HBvd3CNoOauSVXvI+rhdsgTMX0ptnjIiPYwE0RQtxptp+rPjOfuT4JdboM
 AU8f0VKeer1kRPxVbka9YwgVrUw5JqgFkPu2aC9B+ao+4IAM96n6lJje/rC59zkf
 eBclcnOlsQ==
 =jy10
 -----END PGP SIGNATURE-----

Merge tag 'block-5.6-2020-02-16' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Not a lot here, which is great, basically just three small bcache
  fixes from Coly, and four NVMe fixes via Keith"

* tag 'block-5.6-2020-02-16' of git://git.kernel.dk/linux-block:
  nvme: fix the parameter order for nvme_get_log in nvme_get_fw_slot_info
  nvme/pci: move cqe check after device shutdown
  nvme: prevent warning triggered by nvme_stop_keep_alive
  nvme/tcp: fix bug on double requeue when send fails
  bcache: remove macro nr_to_fifo_front()
  bcache: Revert "bcache: shrink btree node cache after bch_btree_check()"
  bcache: ignore pending signals when creating gc and allocator thread
2020-02-16 12:35:52 -08:00
Coly Li
4ec31cb624 bcache: remove macro nr_to_fifo_front()
Macro nr_to_fifo_front() is only used once in btree_flush_write(),
it is unncessary indeed. This patch removes this macro and does
calculation directly in place.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-13 08:53:50 -07:00
Coly Li
309cc719a2 bcache: Revert "bcache: shrink btree node cache after bch_btree_check()"
This reverts commit 1df3877ff6.

In my testing, sometimes even all the cached btree nodes are freed,
creating gc and allocator kernel threads may still fail. Finally it
turns out that kthread_run() may fail if there is pending signal for
current task. And the pending signal is sent from OOM killer which
is triggered by memory consuption in bch_btree_check().

Therefore explicitly shrinking bcache btree node here does not help,
and after the shrinker callback is improved, as well as pending signals
are ignored before creating kernel threads, now such operation is
unncessary anymore.

This patch reverts the commit 1df3877ff6 ("bcache: shrink btree node
cache after bch_btree_check()") because we have better improvement now.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-13 08:53:49 -07:00
Coly Li
0b96da639a bcache: ignore pending signals when creating gc and allocator thread
When run a cache set, all the bcache btree node of this cache set will
be checked by bch_btree_check(). If the bcache btree is very large,
iterating all the btree nodes will occupy too much system memory and
the bcache registering process might be selected and killed by system
OOM killer. kthread_run() will fail if current process has pending
signal, therefore the kthread creating in run_cache_set() for gc and
allocator kernel threads are very probably failed for a very large
bcache btree.

Indeed such OOM is safe and the registering process will exit after
the registration done. Therefore this patch flushes pending signals
during the cache set start up, specificly in bch_cache_allocator_start()
and bch_gc_thread_start(), to make sure run_cache_set() won't fail for
large cahced data set.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-13 08:53:49 -07:00
Linus Torvalds
236f453294 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:

 - bmap series from cmaiolino

 - getting rid of convolutions in copy_mount_options() (use a couple of
   copy_from_user() instead of the __get_user() crap)

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  saner copy_mount_options()
  fibmap: Reject negative block numbers
  fibmap: Use bmap instead of ->bmap method in ioctl_fibmap
  ecryptfs: drop direct calls to ->bmap
  cachefiles: drop direct usage of ->bmap method.
  fs: Enable bmap() function to properly return errors
2020-02-08 13:04:49 -08:00
Linus Torvalds
ed535f2c9e block-5.6-2020-02-05
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl47ML4QHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpvm2EACGaxAxP7pLniNV30cRotF8lPpQ5nUrpiem
 H1r5WqeI5osCGkRKHaJQ4O0Sw8IV2pWzHTWz+9bv56zLM40yIMaEHLRU00AM047n
 KFdA2x4xH+HhbR9lF+flYz1oInlIEXxPiERKm/p1pvQEbquzi4X5cQqv6q2pdzJ9
 sf8OBJhKs4rp/ooqzWwjVOeP/n1sT2r+XDg9C9WC5aXaVZbbLw50r1WRYFt1zf7N
 oa+91fq2lasxK1c79OtbbGJlBXWTurAtUaKBM0KKPguiH2h9j47pAs0HsV02kZ2M
 1ZltwKTyfDNMzBEgvkdB3R0G9nU422nIF+w319i6on8P8xfz8Px13d1KCQGAmfD6
 K1YuaCgOjWuVhOKpMwBq9ql6QVP+1LIMKIl2OGJkrBgl9ZzfE8KMZa2QZTGrGO/U
 xE/hirYdj5T1O8umUQ4cmZHTROASOJZ8/eU9XHA1vf/eJYXiS31/4ewgRzP3oGX2
 5Jvz3o144nBeBTOiFlzs3Fe+wX63QABNG22bijzEGoNTxjXJFroBDYzeiOELjECZ
 /xGRZG1bLOGMj8Gg4ZADSILQDkqISsQHofl1I9mWTbwB1j7g69ZjV8Ie2dyMaX6b
 5z5Smqzd9gcok9hr8NGWkV3c3NypPxIWxrOcyzYbGLUPDGqa+QjGtlLrGgeinhLM
 SitalHw0KA==
 =05d8
 -----END PGP SIGNATURE-----

Merge tag 'block-5.6-2020-02-05' of git://git.kernel.dk/linux-block

Pull more block updates from Jens Axboe:
 "Some later arrivals, but all fixes at this point:

   - bcache fix series (Coly)

   - Series of BFQ fixes (Paolo)

   - NVMe pull request from Keith with a few minor NVMe fixes

   - Various little tweaks"

* tag 'block-5.6-2020-02-05' of git://git.kernel.dk/linux-block: (23 commits)
  nvmet: update AEN list and array at one place
  nvmet: Fix controller use after free
  nvmet: Fix error print message at nvmet_install_queue function
  brd: check and limit max_part par
  nvme-pci: remove nvmeq->tags
  nvmet: fix dsm failure when payload does not match sgl descriptor
  nvmet: Pass lockdep expression to RCU lists
  block, bfq: clarify the goal of bfq_split_bfqq()
  block, bfq: get a ref to a group when adding it to a service tree
  block, bfq: remove ifdefs from around gets/puts of bfq groups
  block, bfq: extend incomplete name of field on_st
  block, bfq: get extra ref to prevent a queue from being freed during a group move
  block, bfq: do not insert oom queue into position tree
  block, bfq: do not plug I/O for bfq_queues with no proc refs
  bcache: check return value of prio_read()
  bcache: fix incorrect data type usage in btree_flush_write()
  bcache: add readahead cache policy options via sysfs interface
  bcache: explicity type cast in bset_bkey_last()
  bcache: fix memory corruption in bch_cache_accounting_clear()
  xen/blkfront: limit allocated memory size to actual use case
  ...
2020-02-06 06:15:23 +00:00
Alexey Dobriyan
97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Carlos Maiolino
30460e1ea3 fs: Enable bmap() function to properly return errors
By now, bmap() will either return the physical block number related to
the requested file offset or 0 in case of error or the requested offset
maps into a hole.
This patch makes the needed changes to enable bmap() to proper return
errors, using the return value as an error return, and now, a pointer
must be passed to bmap() to be filled with the mapped physical block.

It will change the behavior of bmap() on return:

- negative value in case of error
- zero on success or map fell into a hole

In case of a hole, the *block will be zero too

Since this is a prep patch, by now, the only error return is -EINVAL if
->bmap doesn't exist.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-03 08:05:37 -05:00
Coly Li
49d08d596e bcache: check return value of prio_read()
Now if prio_read() failed during starting a cache set, we can print
out error message in run_cache_set() and handle the failure properly.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-01 07:55:39 -07:00
Coly Li
d1c3cc34f5 bcache: fix incorrect data type usage in btree_flush_write()
Dan Carpenter points out that from commit 2aa8c52938 ("bcache: avoid
unnecessary btree nodes flushing in btree_flush_write()"), there is a
incorrect data type usage which leads to the following static checker
warning:
	drivers/md/bcache/journal.c:444 btree_flush_write()
	warn: 'ref_nr' unsigned <= 0

drivers/md/bcache/journal.c
   422  static void btree_flush_write(struct cache_set *c)
   423  {
   424          struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR];
   425          unsigned int i, nr, ref_nr;
                                    ^^^^^^

   426          atomic_t *fifo_front_p, *now_fifo_front_p;
   427          size_t mask;
   428
   429          if (c->journal.btree_flushing)
   430                  return;
   431
   432          spin_lock(&c->journal.flush_write_lock);
   433          if (c->journal.btree_flushing) {
   434                  spin_unlock(&c->journal.flush_write_lock);
   435                  return;
   436          }
   437          c->journal.btree_flushing = true;
   438          spin_unlock(&c->journal.flush_write_lock);
   439
   440          /* get the oldest journal entry and check its refcount */
   441          spin_lock(&c->journal.lock);
   442          fifo_front_p = &fifo_front(&c->journal.pin);
   443          ref_nr = atomic_read(fifo_front_p);
   444          if (ref_nr <= 0) {
                    ^^^^^^^^^^^
Unsigned can't be less than zero.

   445                  /*
   446                   * do nothing if no btree node references
   447                   * the oldest journal entry
   448                   */
   449                  spin_unlock(&c->journal.lock);
   450                  goto out;
   451          }
   452          spin_unlock(&c->journal.lock);

As the warning information indicates, local varaible ref_nr in unsigned
int type is wrong, which does not matche atomic_read() and the "<= 0"
checking.

This patch fixes the above error by defining local variable ref_nr as
int type.

Fixes: 2aa8c52938 ("bcache: avoid unnecessary btree nodes flushing in btree_flush_write()")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-01 07:55:39 -07:00
Coly Li
038ba8cc1b bcache: add readahead cache policy options via sysfs interface
In year 2007 high performance SSD was still expensive, in order to
save more space for real workload or meta data, the readahead I/Os
for non-meta data was bypassed and not cached on SSD.

In now days, SSD price drops a lot and people can find larger size
SSD with more comfortable price. It is unncessary to alway bypass
normal readahead I/Os to save SSD space for now.

This patch adds options for readahead data cache policies via sysfs
file /sys/block/bcache<N>/readahead_cache_policy, the options are,
- "all": cache all readahead data I/Os.
- "meta-only": only cache meta data, and bypass other regular I/Os.

If users want to make bcache continue to only cache readahead request
for metadata and bypass regular data readahead, please set "meta-only"
to this sysfs file. By default, bcache will back to cache all read-
ahead requests now.

Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Acked-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-01 07:55:39 -07:00
Coly Li
7c02b0055f bcache: explicity type cast in bset_bkey_last()
In bset.h, macro bset_bkey_last() is defined as,
    bkey_idx((struct bkey *) (i)->d, (i)->keys)

Parameter i can be variable type of data structure, the macro always
works once the type of struct i has member 'd' and 'keys'.

bset_bkey_last() is also used in macro csum_set() to calculate the
checksum of a on-disk data structure. When csum_set() is used to
calculate checksum of on-disk bcache super block, the parameter 'i'
data type is struct cache_sb_disk. Inside struct cache_sb_disk (also in
struct cache_sb) the member keys is __u16 type. But bkey_idx() expects
unsigned int (a 32bit width), so there is problem when sending
parameters via stack to call bkey_idx().

Sparse tool from Intel 0day kbuild system reports this incompatible
problem. bkey_idx() is part of user space API, so the simplest fix is
to cast the (i)->keys to unsigned int type in macro bset_bkey_last().

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-01 07:55:39 -07:00
Coly Li
5bebf7486d bcache: fix memory corruption in bch_cache_accounting_clear()
Commit 83ff9318c4 ("bcache: not use hard coded memset size in
bch_cache_accounting_clear()") tries to make the code more easy to
understand by removing the hard coded number with following change,
	void bch_cache_accounting_clear(...)
	{
		memset(&acc->total.cache_hits,
			0,
	-		sizeof(unsigned long) * 7);
	+		sizeof(struct cache_stats));
	}

Unfortunately the change was wrong (it also tells us the original code
was not easy to correctly understand). The hard coded number 7 is used
because in struct cache_stats,
 15 struct cache_stats {
 16         struct kobject          kobj;
 17
 18         unsigned long cache_hits;
 19         unsigned long cache_misses;
 20         unsigned long cache_bypass_hits;
 21         unsigned long cache_bypass_misses;
 22         unsigned long cache_readaheads;
 23         unsigned long cache_miss_collisions;
 24         unsigned long sectors_bypassed;
 25
 26         unsigned int            rescale;
 27 };
only members in LINE 18-24 want to be set to 0. It is wrong to use
'sizeof(struct cache_stats)' to replace 'sizeof(unsigned long) * 7), the
memory objects behind acc->total is staled by this change.

Сорокин Артем Сергеевич reports that by the following steps, kernel
panic will be triggered,
1. Create new set: make-bcache -B /dev/nvme1n1 -C /dev/sda --wipe-bcache
2. Run in /sys/fs/bcache/<uuid>:
   echo 1 > clear_stats && cat stats_five_minute/cache_bypass_hits

I can reproduce the panic and get following dmesg with KASAN enabled,
[22613.172742] ==================================================================
[22613.172862] BUG: KASAN: null-ptr-deref in sysfs_kf_seq_show+0x117/0x230
[22613.172864] Read of size 8 at addr 0000000000000000 by task cat/6753

[22613.172870] CPU: 1 PID: 6753 Comm: cat Not tainted 5.5.0-rc7-lp151.28.16-default+ #11
[22613.172872] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/29/2019
[22613.172873] Call Trace:
[22613.172964]  dump_stack+0x8b/0xbb
[22613.172968]  ? sysfs_kf_seq_show+0x117/0x230
[22613.172970]  ? sysfs_kf_seq_show+0x117/0x230
[22613.173031]  __kasan_report+0x176/0x192
[22613.173064]  ? pr_cont_kernfs_name+0x40/0x60
[22613.173067]  ? sysfs_kf_seq_show+0x117/0x230
[22613.173070]  kasan_report+0xe/0x20
[22613.173072]  sysfs_kf_seq_show+0x117/0x230
[22613.173105]  seq_read+0x199/0x6d0
[22613.173110]  vfs_read+0xa5/0x1a0
[22613.173113]  ksys_read+0x110/0x160
[22613.173115]  ? kernel_write+0xb0/0xb0
[22613.173177]  do_syscall_64+0x77/0x290
[22613.173238]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[22613.173241] RIP: 0033:0x7fc2c886ac61
[22613.173244] Code: fe ff ff 48 8d 3d c7 a0 09 00 48 83 ec 08 e8 46 03 02 00 66 0f 1f 44 00 00 8b 05 ca fb 2c 00 48 63 ff 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48 89
[22613.173245] RSP: 002b:00007ffebe776d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[22613.173248] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2c886ac61
[22613.173249] RDX: 0000000000020000 RSI: 00007fc2c8cca000 RDI: 0000000000000003
[22613.173250] RBP: 0000000000020000 R08: ffffffffffffffff R09: 0000000000000000
[22613.173251] R10: 000000000000038c R11: 0000000000000246 R12: 00007fc2c8cca000
[22613.173253] R13: 0000000000000003 R14: 00007fc2c8cca00f R15: 0000000000020000
[22613.173255] ==================================================================
[22613.173256] Disabling lock debugging due to kernel taint
[22613.173350] BUG: kernel NULL pointer dereference, address: 0000000000000000
[22613.178380] #PF: supervisor read access in kernel mode
[22613.180959] #PF: error_code(0x0000) - not-present page
[22613.183444] PGD 0 P4D 0
[22613.184867] Oops: 0000 [#1] SMP KASAN PTI
[22613.186797] CPU: 1 PID: 6753 Comm: cat Tainted: G    B             5.5.0-rc7-lp151.28.16-default+ #11
[22613.191253] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/29/2019
[22613.196706] RIP: 0010:sysfs_kf_seq_show+0x117/0x230
[22613.199097] Code: ff 48 8b 0b 48 8b 44 24 08 48 01 e9 eb a6 31 f6 48 89 cf ba 00 10 00 00 48 89 4c 24 10 e8 b1 e6 e9 ff 4c 89 ff e8 19 07 ea ff <49> 8b 07 48 85 c0 48 89 44 24 08 0f 84 91 00 00 00 49 8b 6d 00 48
[22613.208016] RSP: 0018:ffff8881d4f8fd78 EFLAGS: 00010246
[22613.210448] RAX: 0000000000000000 RBX: ffff8881eb99b180 RCX: ffffffff810d9ef6
[22613.213691] RDX: 0000000000000001 RSI: 0000000000000246 RDI: 0000000000000246
[22613.216893] RBP: 0000000000001000 R08: fffffbfff072ddcd R09: fffffbfff072ddcd
[22613.220075] R10: 0000000000000001 R11: fffffbfff072ddcc R12: ffff8881de5c0200
[22613.223256] R13: ffff8881ed175500 R14: ffff8881eb99b198 R15: 0000000000000000
[22613.226290] FS:  00007fc2c8d3d500(0000) GS:ffff8881f2a80000(0000) knlGS:0000000000000000
[22613.229637] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[22613.231993] CR2: 0000000000000000 CR3: 00000001ec89a004 CR4: 00000000003606e0
[22613.234909] Call Trace:
[22613.235931]  seq_read+0x199/0x6d0
[22613.237259]  vfs_read+0xa5/0x1a0
[22613.239229]  ksys_read+0x110/0x160
[22613.240590]  ? kernel_write+0xb0/0xb0
[22613.242040]  do_syscall_64+0x77/0x290
[22613.243625]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[22613.245450] RIP: 0033:0x7fc2c886ac61
[22613.246706] Code: fe ff ff 48 8d 3d c7 a0 09 00 48 83 ec 08 e8 46 03 02 00 66 0f 1f 44 00 00 8b 05 ca fb 2c 00 48 63 ff 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48 89
[22613.253296] RSP: 002b:00007ffebe776d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[22613.255835] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2c886ac61
[22613.258472] RDX: 0000000000020000 RSI: 00007fc2c8cca000 RDI: 0000000000000003
[22613.260807] RBP: 0000000000020000 R08: ffffffffffffffff R09: 0000000000000000
[22613.263188] R10: 000000000000038c R11: 0000000000000246 R12: 00007fc2c8cca000
[22613.265598] R13: 0000000000000003 R14: 00007fc2c8cca00f R15: 0000000000020000
[22613.268729] Modules linked in: scsi_transport_iscsi af_packet iscsi_ibft iscsi_boot_sysfs vmw_vsock_vmci_transport vsock fuse bnep kvm_intel kvm irqbypass crc32_pclmul crc32c_intel ghash_clmulni_intel snd_ens1371 snd_ac97_codec ac97_bus bcache snd_pcm btusb btrtl btbcm btintel crc64 aesni_intel glue_helper crypto_simd vmw_balloon cryptd bluetooth snd_timer snd_rawmidi snd joydev pcspkr e1000 rfkill vmw_vmci soundcore ecdh_generic ecc gameport i2c_piix4 mptctl ac button hid_generic usbhid sr_mod cdrom ata_generic ehci_pci vmwgfx uhci_hcd drm_kms_helper syscopyarea serio_raw sysfillrect sysimgblt fb_sys_fops ttm ehci_hcd mptspi scsi_transport_spi mptscsih ata_piix mptbase ahci usbcore libahci drm sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua
[22613.292429] CR2: 0000000000000000
[22613.293563] ---[ end trace a074b26a8508f378 ]---
[22613.295138] RIP: 0010:sysfs_kf_seq_show+0x117/0x230
[22613.296769] Code: ff 48 8b 0b 48 8b 44 24 08 48 01 e9 eb a6 31 f6 48 89 cf ba 00 10 00 00 48 89 4c 24 10 e8 b1 e6 e9 ff 4c 89 ff e8 19 07 ea ff <49> 8b 07 48 85 c0 48 89 44 24 08 0f 84 91 00 00 00 49 8b 6d 00 48
[22613.303553] RSP: 0018:ffff8881d4f8fd78 EFLAGS: 00010246
[22613.305280] RAX: 0000000000000000 RBX: ffff8881eb99b180 RCX: ffffffff810d9ef6
[22613.307924] RDX: 0000000000000001 RSI: 0000000000000246 RDI: 0000000000000246
[22613.310272] RBP: 0000000000001000 R08: fffffbfff072ddcd R09: fffffbfff072ddcd
[22613.312685] R10: 0000000000000001 R11: fffffbfff072ddcc R12: ffff8881de5c0200
[22613.315076] R13: ffff8881ed175500 R14: ffff8881eb99b198 R15: 0000000000000000
[22613.318116] FS:  00007fc2c8d3d500(0000) GS:ffff8881f2a80000(0000) knlGS:0000000000000000
[22613.320743] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[22613.322628] CR2: 0000000000000000 CR3: 00000001ec89a004 CR4: 00000000003606e0

Here this patch fixes the following problem by explicity set all the 7
members to 0 in bch_cache_accounting_clear().

Reported-by: Сорокин Артем Сергеевич <a.sorokin@bank-hlynov.ru>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-01 07:55:39 -07:00
Linus Torvalds
e9f8ca0ae7 - Fix DM core's potential for q->make_request_fn NULL pointer in the
unlikely case that a DM device is created without a DM table and
   then accessed due to upper-layer userspace code or user error.
 
 - Fix DM thin-provisioning's metadata_pre_commit_callback to not use
   memory after it is free'd.  Also refactor code to disallow changing
   the thin-pool's data device once in use -- doing so guarantees smae
   lifetime of pool's data device relative to the pool metadata.
 
 - Fix DM space maps used by DM thinp and DM cache to avoid reuse of a
   already used block. This race was identified with extremely heavy
   snapshot use in the context of DM thin provisioning.
 
 - Fix DM raid's table status relative to an active rebuild.
 
 - Fix DM crypt to use GFP_NOIO rather than GFP_NOFS in call to
   skcipher_request_alloc(). Also fix benbi IV constructor crash if
   used in authenticated mode.
 
 - Add DM crypt support for Elephant diffuser to allow for Bitlocker
   compatibility.
 
 - Fix DM verity target to not prefetch hash blocks for data that has
   already been verified.
 
 - Fix DM writecache's incorrect flush sequence during commit when in
   SSD mode.
 
 - Improve DM writecache's sequential write performance on SSDs.
 
 - Add DM zoned target support for zone sizes smaller than 128MiB.
 
 - Add DM multipath 'queue_if_no_path_timeout_secs' module param to
   allow timeout if path isn't reinstated. This allows users a kernel
   safety-net against IO hanging indefinitely, due to no active paths,
   that has historically only been provided by multipathd userspace.
 
 - Various DM code cleanups to use true/false rather than 1/0, a
   variable rename in dm-dust, and fix for a math error in comment for
   DM thin metadata's ondisk format.
 -----BEGIN PGP SIGNATURE-----
 
 iQFHBAABCAAxFiEEJfWUX4UqZ4x1O2wixSPxCi2dA1oFAl4xvEITHHNuaXR6ZXJA
 cmVkaGF0LmNvbQAKCRDFI/EKLZ0DWipYCAC+sX8q/XBDRi4WDCTvCRCcBfz9g9ZO
 oygimV64oYf08JiDL54Z29T0EjwGR6DcZB0nEyjhl2/lU4bPwd4kLc/VHwjf44ay
 oUJWZxp8Az7pIWjQQ5oC09it8gLmDpBdq2Z146tEDgYrERnH8BgDObYm3ihXwi9f
 zMoET8rIzNltMUo6jIumjzxPcLbBsRTnC35mE//PZkMiUUI3ucNWuOhD/ICDe/Tu
 VQ9rNtJx01xs07bFKT4OYR2Oc7xrtWEOMDKeSFz16j8t28wywLFz3EPXRG7tKM3l
 6CKBFdRqPSL6v2Mr1QD8YwJJCPLsCoOQ14aKn2sDPG8EgQMnh7R2g6OT
 =mfnM
 -----END PGP SIGNATURE-----

Merge tag 'for-5.6/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Fix DM core's potential for q->make_request_fn NULL pointer in the
   unlikely case that a DM device is created without a DM table and then
   accessed due to upper-layer userspace code or user error.

 - Fix DM thin-provisioning's metadata_pre_commit_callback to not use
   memory after it is free'd. Also refactor code to disallow changing
   the thin-pool's data device once in use -- doing so guarantees smae
   lifetime of pool's data device relative to the pool metadata.

 - Fix DM space maps used by DM thinp and DM cache to avoid reuse of a
   already used block. This race was identified with extremely heavy
   snapshot use in the context of DM thin provisioning.

 - Fix DM raid's table status relative to an active rebuild.

 - Fix DM crypt to use GFP_NOIO rather than GFP_NOFS in call to
   skcipher_request_alloc(). Also fix benbi IV constructor crash if used
   in authenticated mode.

 - Add DM crypt support for Elephant diffuser to allow for Bitlocker
   compatibility.

 - Fix DM verity target to not prefetch hash blocks for data that has
   already been verified.

 - Fix DM writecache's incorrect flush sequence during commit when in
   SSD mode.

 - Improve DM writecache's sequential write performance on SSDs.

 - Add DM zoned target support for zone sizes smaller than 128MiB.

 - Add DM multipath 'queue_if_no_path_timeout_secs' module param to
   allow timeout if path isn't reinstated. This allows users a kernel
   safety-net against IO hanging indefinitely, due to no active paths,
   that has historically only been provided by multipathd userspace.

 - Various DM code cleanups to use true/false rather than 1/0, a
   variable rename in dm-dust, and fix for a math error in comment for
   DM thin metadata's ondisk format.

* tag 'for-5.6/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (21 commits)
  dm: fix potential for q->make_request_fn NULL pointer
  dm writecache: improve performance of large linear writes on SSDs
  dm mpath: Add timeout mechanism for queue_if_no_path
  dm thin: change data device's flush_bio to be member of struct pool
  dm thin: don't allow changing data device during thin-pool reload
  dm thin: fix use-after-free in metadata_pre_commit_callback
  dm thin metadata: use pool locking at end of dm_pool_metadata_close
  dm writecache: fix incorrect flush sequence when doing SSD mode commit
  dm crypt: fix benbi IV constructor crash if used in authenticated mode
  dm crypt: Implement Elephant diffuser for Bitlocker compatibility
  dm space map common: fix to ensure new block isn't already in use
  dm verity: don't prefetch hash blocks for already-verified data
  dm crypt: fix GFP flags passed to skcipher_request_alloc()
  dm thin metadata: Fix trivial math error in on-disk format documentation
  dm thin metadata: use true/false for bool variable
  dm snapshot: use true/false for bool variable
  dm bio prison v2: use true/false for bool variable
  dm mpath: use true/false for bool variable
  dm zoned: support zone sizes smaller than 128MiB
  dm raid: table line rebuild status fixes
  ...
2020-01-29 18:08:49 -08:00
Linus Torvalds
22a8f39c52 for-5.6/drivers-2020-01-27
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl4vOrAQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgph+HD/9bM9CqjchDitL0NQne+4BwBdoRCcik0z7n
 y/CrNIh3tZnkJO0fT9Lz6GD/6iZNU93NUHFMOgzuS+8mR5CwQUkR/xjDvPX8H07F
 h+Xl8ZUX6YjbuLmO0sgc9yu3SkMaxjCHfGPl1juZXwH6ERM6MTSkg6O+YwQZnvAB
 lLJWaa1oOTQAsbnz7ZVwZ5pDOfkoSirCat2kzPoyfzptcIrUw7vfu4QHdCdNHy63
 eT/vcHmj6CqzZWJRfpkaFOY6fnY30Hh9fqAVQvzxHPvm1vM3z7JSw7cY8t+cjXjn
 TJ0NQK2QFmGTTa/ZEf3KCB5kbNV0SpOV6Jqz1aBX/cStQez6ygFkPGscPbwy8tsR
 vBVDyCMZC42jbt7TuIHNkAI/e+HqSOBgyB8MaWaQfApcbNzTIFp9lltrTcZpaYNZ
 J4R6YQGDve+ElUlOAPBbiXRGrd3jmhApP8scbgls05UwZOtDf+KJBCLQYRzw8qrb
 J7D7hVugwV0oDhdaUkd4Pt3KYoISsFgIe7HRuKGGmfKyqWiJ5iLH0QVPaEkPAokr
 VzzSoex+5xcCSvIiGd1DNzsVD9C2xbyUvifHTa36pYKQ65BogyJBopgYgEYd8ksN
 AlmPxJM9j1o85TtV1CAbb2O0827BlLmYLc6BcdD+s0x+FeStdnjwICQooHiitTiI
 hEHajSDujQ==
 =Us3h
 -----END PGP SIGNATURE-----

Merge tag 'for-5.6/drivers-2020-01-27' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Like the core side, not a lot of changes here, just two main items:

   - Series of patches (via Coly) with fixes for bcache (Coly,
     Christoph)

   - MD pull request from Song"

* tag 'for-5.6/drivers-2020-01-27' of git://git.kernel.dk/linux-block: (31 commits)
  bcache: reap from tail of c->btree_cache in bch_mca_scan()
  bcache: reap c->btree_cache_freeable from the tail in bch_mca_scan()
  bcache: remove member accessed from struct btree
  bcache: print written and keys in trace_bcache_btree_write
  bcache: avoid unnecessary btree nodes flushing in btree_flush_write()
  bcache: add code comments for state->pool in __btree_sort()
  lib: crc64: include <linux/crc64.h> for 'crc64_be'
  bcache: use read_cache_page_gfp to read the superblock
  bcache: store a pointer to the on-disk sb in the cache and cached_dev structures
  bcache: return a pointer to the on-disk sb from read_super
  bcache: transfer the sb_page reference to register_{bdev,cache}
  bcache: fix use-after-free in register_bcache()
  bcache: properly initialize 'path' and 'err' in register_bcache()
  bcache: rework error unwinding in register_bcache
  bcache: use a separate data structure for the on-disk super block
  bcache: cached_dev_free needs to put the sb page
  md/raid1: introduce wait_for_serialization
  md/raid1: use bucket based mechanism for IO serialization
  md: introduce a new struct for IO serialization
  md: don't destroy serial_info_pool if serialize_policy is true
  ...
2020-01-27 12:55:48 -08:00
Mike Snitzer
47ace7e012 dm: fix potential for q->make_request_fn NULL pointer
Move blk_queue_make_request() to dm.c:alloc_dev() so that
q->make_request_fn is never NULL during the lifetime of a DM device
(even one that is created without a DM table).

Otherwise generic_make_request() will crash simply by doing:
  dmsetup create -n test
  mount /dev/dm-N /mnt

While at it, move ->congested_data initialization out of
dm.c:alloc_dev() and into the bio-based specific init method.

Reported-by: Stefan Bader <stefan.bader@canonical.com>
BugLink: https://bugs.launchpad.net/bugs/1860231
Fixes: ff36ab3458 ("dm: remove request-based logic from make_request_fn wrapper")
Depends-on: c12c9a3c38 ("dm: various cleanups to md->queue initialization code")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-27 14:52:36 -05:00
Coly Li
e3de04469a bcache: reap from tail of c->btree_cache in bch_mca_scan()
When shrink btree node cache from c->btree_cache in bch_mca_scan(),
no matter the selected node is reaped or not, it will be rotated from
the head to the tail of c->btree_cache list. But in bcache journal
code, when flushing the btree nodes with oldest journal entry, btree
nodes are iterated and slected from the tail of c->btree_cache list in
btree_flush_write(). The list_rotate_left() in bch_mca_scan() will
make btree_flush_write() iterate more nodes in c->btree_list in reverse
order.

This patch just reaps the selected btree node cache, and not move it
from the head to the tail of c->btree_cache list. Then bch_mca_scan()
will not mess up c->btree_cache list to btree_flush_write().

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:02 -07:00
Coly Li
d5c9c470b0 bcache: reap c->btree_cache_freeable from the tail in bch_mca_scan()
In order to skip the most recently freed btree node cahce, currently
in bch_mca_scan() the first 3 caches in c->btree_cache_freeable list
are skipped when shrinking bcache node caches in bch_mca_scan(). The
related code in bch_mca_scan() is,

 737 list_for_each_entry_safe(b, t, &c->btree_cache_freeable, list) {
 738         if (nr <= 0)
 739                 goto out;
 740
 741         if (++i > 3 &&
 742             !mca_reap(b, 0, false)) {
             		lines free cache memory
 746         }
 747         nr--;
 748 }

The problem is, if virtual memory code calls bch_mca_scan() and
the calculated 'nr' is 1 or 2, then in the above loop, nothing will
be shunk. In such case, if slub/slab manager calls bch_mca_scan()
for many times with small scan number, it does not help to shrink
cache memory and just wasts CPU cycles.

This patch just selects btree node caches from tail of the
c->btree_cache_freeable list, then the newly freed host cache can
still be allocated by mca_alloc(), and at least 1 node can be shunk.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:02 -07:00
Coly Li
125d98edd1 bcache: remove member accessed from struct btree
The member 'accessed' of struct btree is used in bch_mca_scan() when
shrinking btree node caches. The original idea is, if b->accessed is
set, clean it and look at next btree node cache from c->btree_cache
list, and only shrink the caches whose b->accessed is cleaned. Then
only cold btree node cache will be shrunk.

But when I/O pressure is high, it is very probably that b->accessed
of a btree node cache will be set again in bch_btree_node_get()
before bch_mca_scan() selects it again. Then there is no chance for
bch_mca_scan() to shrink enough memory back to slub or slab system.

This patch removes member accessed from struct btree, then once a
btree node ache is selected, it will be immediately shunk. By this
change, bch_mca_scan() may release btree node cahce more efficiently.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:02 -07:00
Coly Li
2aa8c52938 bcache: avoid unnecessary btree nodes flushing in btree_flush_write()
the commit 91be66e131 ("bcache: performance improvement for
btree_flush_write()") was an effort to flushing btree node with oldest
btree node faster in following methods,
- Only iterate dirty btree nodes in c->btree_cache, avoid scanning a lot
  of clean btree nodes.
- Take c->btree_cache as a LRU-like list, aggressively flushing all
  dirty nodes from tail of c->btree_cache util the btree node with
  oldest journal entry is flushed. This is to reduce the time of holding
  c->bucket_lock.

Guoju Fang and Shuang Li reported that they observe unexptected extra
write I/Os on cache device after applying the above patch. Guoju Fang
provideed more detailed diagnose information that the aggressive
btree nodes flushing may cause 10x more btree nodes to flush in his
workload. He points out when system memory is large enough to hold all
btree nodes in memory, c->btree_cache is not a LRU-like list any more.
Then the btree node with oldest journal entry is very probably not-
close to the tail of c->btree_cache list. In such situation much more
dirty btree nodes will be aggressively flushed before the target node
is flushed. When slow SATA SSD is used as cache device, such over-
aggressive flushing behavior will cause performance regression.

After spending a lot of time on debug and diagnose, I find the real
condition is more complicated, aggressive flushing dirty btree nodes
from tail of c->btree_cache list is not a good solution.
- When all btree nodes are cached in memory, c->btree_cache is not
  a LRU-like list, the btree nodes with oldest journal entry won't
  be close to the tail of the list.
- There can be hundreds dirty btree nodes reference the oldest journal
  entry, before flushing all the nodes the oldest journal entry cannot
  be reclaimed.
When the above two conditions mixed together, a simply flushing from
tail of c->btree_cache list is really NOT a good idea.

Fortunately there is still chance to make btree_flush_write() work
better. Here is how this patch avoids unnecessary btree nodes flushing,
- Only acquire c->journal.lock when getting oldest journal entry of
  fifo c->journal.pin. In rested locations check the journal entries
  locklessly, so their values can be changed on other cores
  in parallel.
- In loop list_for_each_entry_safe_reverse(), checking latest front
  point of fifo c->journal.pin. If it is different from the original
  point which we get with locking c->journal.lock, it means the oldest
  journal entry is reclaim on other cores. At this moment, all selected
  dirty nodes recorded in array btree_nodes[] are all flushed and clean
  on other CPU cores, it is unncessary to iterate c->btree_cache any
  longer. Just quit the list_for_each_entry_safe_reverse() loop and
  the following for-loop will skip all the selected clean nodes.
- Find a proper time to quit the list_for_each_entry_safe_reverse()
  loop. Check the refcount value of orignial fifo front point, if the
  value is larger than selected node number of btree_nodes[], it means
  more matching btree nodes should be scanned. Otherwise it means no
  more matching btee nodes in rest of c->btree_cache list, the loop
  can be quit. If the original oldest journal entry is reclaimed and
  fifo front point is updated, the refcount of original fifo front point
  will be 0, then the loop will be quit too.
- Not hold c->bucket_lock too long time. c->bucket_lock is also required
  for space allocation for cached data, hold it for too long time will
  block regular I/O requests. When iterating list c->btree_cache, even
  there are a lot of maching btree nodes, in order to not holding
  c->bucket_lock for too long time, only BTREE_FLUSH_NR nodes are
  selected and to flush in following for-loop.
With this patch, only btree nodes referencing oldest journal entry
are flushed to cache device, no aggressive flushing for  unnecessary
btree node any more. And in order to avoid blocking regluar I/O
requests, each time when btree_flush_write() called, at most only
BTREE_FLUSH_NR btree nodes are selected to flush, even there are more
maching btree nodes in list c->btree_cache.

At last, one more thing to explain: Why it is safe to read front point
of c->journal.pin without holding c->journal.lock inside the
list_for_each_entry_safe_reverse() loop ?

Here is my answer: When reading the front point of fifo c->journal.pin,
we don't need to know the exact value of front point, we just want to
check whether the value is different from the original front point
(which is accurate value because we get it while c->jouranl.lock is
held). For such purpose, it works as expected without holding
c->journal.lock. Even the front point is changed on other CPU core and
not updated to local core, and current iterating btree node has
identical journal entry local as original fetched fifo front point, it
is still safe. Because after holding mutex b->write_lock (with memory
barrier) this btree node can be found as clean and skipped, the loop
will quite latter when iterate on next node of list c->btree_cache.

Fixes: 91be66e131 ("bcache: performance improvement for btree_flush_write()")
Reported-by: Guoju Fang <fangguoju@gmail.com>
Reported-by: Shuang Li <psymon@bonuscloud.io>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:02 -07:00
Coly Li
7a0bc2a896 bcache: add code comments for state->pool in __btree_sort()
To explain the pages allocated from mempool state->pool can be
swapped in __btree_sort(), because state->pool is a page pool,
which allocates pages by alloc_pages() indeed.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:02 -07:00
Christoph Hellwig
6321bef028 bcache: use read_cache_page_gfp to read the superblock
Avoid a pointless dependency on buffer heads in bcache by simply open
coding reading a single page.  Also add a SB_OFFSET define for the
byte offset of the superblock instead of using magic numbers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:01 -07:00
Christoph Hellwig
475389ae5c bcache: store a pointer to the on-disk sb in the cache and cached_dev structures
This allows to properly build the superblock bio including the offset in
the page using the normal bio helpers.  This fixes writing the superblock
for page sizes larger than 4k where the sb write bio would need an offset
in the bio_vec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:01 -07:00
Christoph Hellwig
cfa0c56db9 bcache: return a pointer to the on-disk sb from read_super
Returning the properly typed actual data structure insteaf of the
containing struct page will save the callers some work going
forward.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:01 -07:00
Christoph Hellwig
fc8f19cc5d bcache: transfer the sb_page reference to register_{bdev,cache}
Avoid an extra reference count roundtrip by transferring the sb_page
ownership to the lower level register helpers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:01 -07:00
Coly Li
ae3cd29991 bcache: fix use-after-free in register_bcache()
The patch "bcache: rework error unwinding in register_bcache" introduces
a use-after-free regression in register_bcache(). Here are current code,
	2510 out_free_path:
	2511         kfree(path);
	2512 out_module_put:
	2513         module_put(THIS_MODULE);
	2514 out:
	2515         pr_info("error %s: %s", path, err);
	2516         return ret;
If some error happens and the above code path is executed, at line 2511
path is released, but referenced at line 2515. Then KASAN reports a use-
after-free error message.

This patch changes line 2515 in the following way to fix the problem,
	2515         pr_info("error %s: %s", path?path:"", err);

Signed-off-by: Coly Li <colyli@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:01 -07:00
Coly Li
29cda393bc bcache: properly initialize 'path' and 'err' in register_bcache()
Patch "bcache: rework error unwinding in register_bcache" from
Christoph Hellwig changes the local variables 'path' and 'err'
in undefined initial state. If the code in register_bcache() jumps
to label 'out:' or 'out_module_put:' by goto, these two variables
might be reference with undefined value by the following line,

	out_module_put:
	        module_put(THIS_MODULE);
	out:
	        pr_info("error %s: %s", path, err);
	        return ret;

Therefore this patch initializes these two local variables properly
in register_bcache() to avoid such issue.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:01 -07:00
Christoph Hellwig
50246693f8 bcache: rework error unwinding in register_bcache
Split the successful and error return path, and use one goto label for each
resource to unwind.  This also fixes some small errors like leaking the
module reference count in the reboot case (which seems entirely harmless)
or printing the wrong warning messages for early failures.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:01 -07:00
Christoph Hellwig
a702a692cd bcache: use a separate data structure for the on-disk super block
Split out an on-disk version struct cache_sb with the proper endianness
annotations.  This fixes a fair chunk of sparse warnings, but there are
some left due to the way the checksum is defined.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:00 -07:00
Liang Chen
e8547d4209 bcache: cached_dev_free needs to put the sb page
Same as cache device, the buffer page needs to be put while
freeing cached_dev.  Otherwise a page would be leaked every
time a cached_dev is stopped.

Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-23 11:40:00 -07:00
Mikulas Patocka
dcd195071f dm writecache: improve performance of large linear writes on SSDs
When dm-writecache is used with SSD as a cache device, it would submit a
separate bio for each written block. The I/Os would be merged by the disk
scheduler, but this merging degrades performance.

Improve dm-writecache performance by submitting larger bios - this is
possible as long as there is consecutive free space on the cache
device.

Benchmark (arm64 with 64k page size, using /dev/ram0 as a cache device):

fio --bs=512k --iodepth=32 --size=400M --direct=1 \
    --filename=/dev/mapper/cache --rw=randwrite --numjobs=1 --name=test

block	old	new
size	MiB/s	MiB/s
---------------------
512	181	700
1k	347	1256
2k	644	2020
4k	1183	2759
8k	1852	3333
16k	2469	3509
32k	2974	3670
64k	3404	3810

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-16 13:34:17 -05:00
Mikulas Patocka
ad6bf88a6c block: fix an integer overflow in logical block size
Logical block size has type unsigned short. That means that it can be at
most 32768. However, there are architectures that can run with 64k pages
(for example arm64) and on these architectures, it may be possible to
create block devices with 64k block size.

For exmaple (run this on an architecture with 64k pages):

Mount will fail with this error because it tries to read the superblock using 2-sector
access:
  device-mapper: writecache: I/O is not aligned, sector 2, size 1024, block size 65536
  EXT4-fs (dm-0): unable to read superblock

This patch changes the logical block size from unsigned short to unsigned
int to avoid the overflow.

Cc: stable@vger.kernel.org
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-15 21:43:09 -07:00
Anatol Pomazau
be240ff5e4 dm mpath: Add timeout mechanism for queue_if_no_path
Add a configurable timeout mechanism to disable queue_if_no_path without
assistance from userspace multipathd.  This reimplements multipathd's
no_path_retry mechanism in kernel space.  This is motivated by the
desire to prevent processes from hanging indefinitely waiting for IO
in cases where multipathd might be unable to respond (after a failure
or for whatever reason).

Despite replicating userspace multipathd's policy configuration in
kernel space, it is important to prevent IOs from hanging forever,
waiting for userspace that may be incapable of behaving correctly.

Use of the provided "queue_if_no_path_timeout_secs" dm-multipath
module parameter is optional.  This timeout mechanism is disabled by
default (by being set to 0).

Signed-off-by: Anatol Pomazau <anatol@google.com>
Co-developed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:23:14 -05:00
Mikulas Patocka
f06c03d1de dm thin: change data device's flush_bio to be member of struct pool
With commit fe64369163c5 ("dm thin: don't allow changing data device
during thin-pool load") it is now possible to re-parent the data
device's flush_bio from the pool_c to pool structure.  Doing so offers
improved lifetime guarantees for the flush_bio so that the call to
dm_pool_register_pre_commit_callback can now be done safely from
pool_ctr().

Depends-on: fe64369163c5 ("dm thin: don't allow changing data device during thin-pool load")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:23:13 -05:00
Mikulas Patocka
873937e75f dm thin: don't allow changing data device during thin-pool reload
The existing code allows changing the data device when the thin-pool
target is reloaded.

This capability is not required and only complicates device lifetime
guarantees. This can cause crashes like the one reported here:
	https://bugzilla.redhat.com/show_bug.cgi?id=1788596
where the kernel tries to issue a flush bio located in a structure that
was already freed.

Take the first step to simplifying the thin-pool's data device lifetime
by disallowing changing it. Like the thin-pool's metadata device, the
data device is now set in pool_create() and it cannot be changed for a
given thin-pool.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:51 -05:00
Mike Snitzer
a4a8d28658 dm thin: fix use-after-free in metadata_pre_commit_callback
dm-thin uses struct pool to hold the state of the pool. There may be
multiple pool_c's pointing to a given pool, each pool_c represents a
loaded target. pool_c's may be created and destroyed arbitrarily and the
pool contains a reference count of pool_c's pointing to it.

Since commit 694cfe7f31 ("dm thin: Flush data device before
committing metadata") a pointer to pool_c is passed to
dm_pool_register_pre_commit_callback and this function stores it in
pmd->pre_commit_context. If this pool_c is freed, but pool is not
(because there is another pool_c referencing it), we end up in a
situation where pmd->pre_commit_context structure points to freed
pool_c. It causes a crash in metadata_pre_commit_callback.

Fix this by moving the dm_pool_register_pre_commit_callback() from
pool_ctr() to pool_preresume(). This way the in-core thin-pool metadata
is only ever armed with callback data whose lifetime matches the
active thin-pool target.

In should be noted that this fix preserves the ability to load a
thin-pool table that uses a different data block device (that contains
the same data) -- though it is unclear if that capability is still
useful and/or needed.

Fixes: 694cfe7f31 ("dm thin: Flush data device before committing metadata")
Cc: stable@vger.kernel.org
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:50 -05:00
Mike Snitzer
44d8ebf436 dm thin metadata: use pool locking at end of dm_pool_metadata_close
Ensure that the pool is locked during calls to __commit_transaction and
__destroy_persistent_data_objects.  Just being consistent with locking,
but reality is dm_pool_metadata_close is called once pool is being
destroyed so access to pool shouldn't be contended.

Also, use pmd_write_lock_in_core rather than __pmd_write_lock in
dm_pool_commit_metadata and rename __pmd_write_lock to
pmd_write_lock_in_core -- there was no need for the alias.

In addition, verify that the pool is locked in __commit_transaction().

Fixes: 873f258bec ("dm thin metadata: do not write metadata if no changes occurred")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:49 -05:00
Mikulas Patocka
aa9509209c dm writecache: fix incorrect flush sequence when doing SSD mode commit
When committing state, the function writecache_flush does the following:
1. write metadata (writecache_commit_flushed)
2. flush disk cache (writecache_commit_flushed)
3. wait for data writes to complete (writecache_wait_for_ios)
4. increase superblock seq_count
5. write the superblock
6. flush disk cache

It may happen that at step 3, when we wait for some write to finish, the
disk may report the write as finished, but the write only hit the disk
cache and it is not yet stored in persistent storage. At step 5 we write
the superblock - it may happen that the superblock is written before the
write that we waited for in step 3. If the machine crashes, it may result
in incorrect data being returned after reboot.

In order to fix the bug, we must swap steps 2 and 3 in the above sequence,
so that we first wait for writes to complete and then flush the disk
cache.

Fixes: 48debafe4f ("dm: add writecache target")
Cc: stable@vger.kernel.org # 4.18+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:48 -05:00
Milan Broz
4ea9471fbd dm crypt: fix benbi IV constructor crash if used in authenticated mode
If benbi IV is used in AEAD construction, for example:
  cryptsetup luksFormat <device> --cipher twofish-xts-benbi --key-size 512 --integrity=hmac-sha256
the constructor uses wrong skcipher function and crashes:

 BUG: kernel NULL pointer dereference, address: 00000014
 ...
 EIP: crypt_iv_benbi_ctr+0x15/0x70 [dm_crypt]
 Call Trace:
  ? crypt_subkey_size+0x20/0x20 [dm_crypt]
  crypt_ctr+0x567/0xfc0 [dm_crypt]
  dm_table_add_target+0x15f/0x340 [dm_mod]

Fix this by properly using crypt_aead_blocksize() in this case.

Fixes: ef43aa3806 ("dm crypt: add cryptographic data integrity protection (authenticated encryption)")
Cc: stable@vger.kernel.org # v4.12+
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=941051
Reported-by: Jerad Simpson <jbsimpson@gmail.com>
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:47 -05:00
Milan Broz
bbb1658461 dm crypt: Implement Elephant diffuser for Bitlocker compatibility
Add experimental support for BitLocker encryption with CBC mode and
additional Elephant diffuser.

The mode was used in older Windows systems and it is provided mainly
for compatibility reasons. The userspace support to activate these
devices is being added to cryptsetup utility.

Read-write activation of such a device is very simple, for example:
  echo <password> | cryptsetup bitlkOpen bitlk_image.img test

The Elephant diffuser uses two rotations in opposite direction for
data (Diffuser A and B) and also XOR operation with Sector key over
the sector data; Sector key is derived from additional key data. The
original public documentation is available here:
  http://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf

The dm-crypt implementation is embedded to "elephant" IV (similar to
tcw IV construction).

Because we cannot modify original bio data for write (before
encryption), an additional internal flag to pre-process data is
added.

Signed-off-by: Milan Broz <gmazyland@gmail.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:46 -05:00
Joe Thornber
4feaef830d dm space map common: fix to ensure new block isn't already in use
The space-maps track the reference counts for disk blocks allocated by
both the thin-provisioning and cache targets.  There are variants for
tracking metadata blocks and data blocks.

Transactionality is implemented by never touching blocks from the
previous transaction, so we can rollback in the event of a crash.

When allocating a new block we need to ensure the block is free (has
reference count of 0) in both the current and previous transaction.
Prior to this fix we were doing this by searching for a free block in
the previous transaction, and relying on a 'begin' counter to track
where the last allocation in the current transaction was.  This
'begin' field was not being updated in all code paths (eg, increment
of a data block reference count due to breaking sharing of a neighbour
block in the same btree leaf).

This fix keeps the 'begin' field, but now it's just a hint to speed up
the search.  Instead the current transaction is searched for a free
block, and then the old transaction is double checked to ensure it's
free.  Much simpler.

This fixes reports of sm_disk_new_block()'s BUG_ON() triggering when
DM thin-provisioning's snapshots are heavily used.

Reported-by: Eric Wheeler <dm-devel@lists.ewheeler.net>
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:15:53 -05:00
Guoqing Jiang
d0d2d8ba04 md/raid1: introduce wait_for_serialization
Previously, we call check_and_add_serial when serialization is
enabled for write IO, but it could allocate and free memory
back and forth.

Now, let's just get an element from memory pool with the new
function, then insert node to rb tree if no collision happens.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:10 -08:00
Guoqing Jiang
025471f9f5 md/raid1: use bucket based mechanism for IO serialization
Since raid1 had already used bucket based mechanism to reduce
the conflict between write IO and resync IO, it is possible to
speed up performance for io serialization with refer to the
same mechanism.

To align with the barrier bucket mechanism, we created arrays
(with the same number of BARRIER_BUCKETS_NR) for spinlock, rb
tree and waitqueue. Then we can reduce lock competition with
multiple spinlocks, boost search performance with multiple rb
trees and also reduce thundering herd problem with multiple
waitqueues.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:10 -08:00
Guoqing Jiang
69b00b5bb2 md: introduce a new struct for IO serialization
Obviously, IO serialization could cause the degradation of
performance a lot. In order to reduce the degradation, so a
rb interval tree is added in raid1 to speed up the check of
collision.

So, a rb root is needed in md_rdev, then abstract all the
serialize related members to a new struct (serial_in_rdev),
embed it into md_rdev.

Of course, we need to free the struct if it is not needed
anymore, so rdev/rdevs_uninit_serial are added accordingly.
And they should be called when destroty memory pool or can't
alloc memory.

And we need to consider to call mddev_destroy_serial_pool
in case serialize_policy/write-behind is disabled, bitmap
is destroyed or in __md_stop_writes.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:10 -08:00
Guoqing Jiang
4d26d32fe4 md: don't destroy serial_info_pool if serialize_policy is true
The serial_info_pool is needed if array sets serialize_policy to
true, so don't destroy it.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:10 -08:00
Guoqing Jiang
69df9cfc70 raid1: serialize the overlap write
Before dispatch write bio, raid1 array which enables
serialize_policy need to check if overlap exists between
this bio and previous on-flying bios. If there is overlap,
then it has to wait until the collision is disappeared.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Guoqing Jiang
de31ee9497 md: reorgnize mddev_create/destroy_serial_pool
So far, IO serialization is used for two scenarios:

1. raid1 which enables write-behind mode, and there is rdev in the array
which is multi-queue device and flaged with writemostly.
2. IO serialization is enabled or disabled by change serialize_policy.

So introduce rdev_need_serial to check the first scenario. And for 1, IO
serialization is enabled automatically while 2 is controlled manually.

And it is possible that both scenarios are true, so for create serial pool,
rdev/rdevs_init_serial should be separate from check if the pool existed or
not. Then for destroy pool, we need to check if the pool is needed by other
rdevs due to the first scenario.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Guoqing Jiang
3938f5fb82 md: add serialize_policy sysfs node for raid1
With the new sysfs node, we can use it to control if raid1 array
wants io serialization or not. So mddev_create_serial_pool and
mddev_destroy_serial_pool are called in serialize_policy_store
to enable or disable the serialization.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Guoqing Jiang
11d3a9f650 md: prepare for enable raid1 io serialization
1. The related resources (spin_lock, list and waitqueue) are needed for
address raid1 reorder overlap issue too, in this case, rdev is set to
NULL for mddev_create/destroy_serial_pool which implies all rdevs need
to handle these resources.

And also add "is_suspend" to mddev_destroy_serial_pool since it will
be called under suspended situation, which also makes both create and
destroy pool have same arguments.

2. Introduce rdevs_init_serial which is called if raid1 io serialization
is enabled since all rdevs need to init related stuffs.

3. rdev_init_serial and clear_bit(CollisionCheck, &rdev->flags) should
be called between suspend and resume.

No need to export mddev_create_serial_pool since it is only called in
md-mod module.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Guoqing Jiang
3e173ab55b md: fix a typo s/creat/create
It actually means create here, so fix the typo.

Reported-by: Song Liu <liu.song.a23@gmail.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Guoqing Jiang
404659cf1e md: rename wb stuffs
Previously, wb_info_pool and wb_list stuffs are introduced
to address potential data inconsistence issue for write
behind device.

Now rename them to serial related name, since the same
mechanism will be used to address reorder overlap write
issue for raid1.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Guoqing Jiang
d2c9ad4124 raid5: remove worker_cnt_per_group argument from alloc_thread_groups
We can use "cnt" directly to update conf->worker_cnt_per_group
if alloc_thread_groups returns 0.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Zhiqiang Liu
55180498df md-bitmap: small cleanups
In md_bitmap_unplug, bitmap->storage.filemap is double checked.

In md_bitmap_daemon_work, bitmap->storage.filemap should be checked
before reference.

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
xianrong.zhou
0a531c5a39 dm verity: don't prefetch hash blocks for already-verified data
Try to skip prefetching hash blocks that won't be needed due to the
"check_at_most_once" option being enabled and the corresponding data
blocks already having been verified.

Since prefetching operates on a range of data blocks, do this by just
trimming the two ends of the range.  This doesn't skip every unneeded
hash block, since data blocks in the middle of the range could also be
unneeded, and hash blocks are still prefetched in large clusters as
controlled by dm_verity_prefetch_cluster.  But it can still help a lot.

In a test on Android Q launching 91 apps every 15s repeated 21 times,
prefetching was only done for 447177/4776629 = 9.36% of data blocks.

Tested-by: ruxian.feng <ruxian.feng@transsion.com>
Co-developed-by: yuanjiong.gao <yuanjiong.gao@transsion.com>
Signed-off-by: yuanjiong.gao <yuanjiong.gao@transsion.com>
Signed-off-by: xianrong.zhou <xianrong.zhou@transsion.com>
[EB: simplified the 'while' loops and improved the commit message]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 12:07:33 -05:00
Mikulas Patocka
9402e95901 dm crypt: fix GFP flags passed to skcipher_request_alloc()
GFP_KERNEL is not supposed to be or'd with GFP_NOFS (the result is
equivalent to GFP_KERNEL). Also, we use GFP_NOIO instead of GFP_NOFS
because we don't want any I/O being submitted in the direct reclaim
path.

Fixes: 39d13a1ac4 ("dm crypt: reuse eboiv skcipher for IV generation")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 12:07:32 -05:00
Jeffle Xu
4306904053 dm thin metadata: Fix trivial math error in on-disk format documentation
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 12:07:31 -05:00
zhengbin
63ee92d1c2 dm thin metadata: use true/false for bool variable
Fixes coccicheck warning:

drivers/md/dm-thin-metadata.c:814:3-14: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-thin-metadata.c:1109:1-12: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-thin-metadata.c:1621:1-12: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-thin-metadata.c:1652:1-12: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-thin-metadata.c:1706:1-12: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 12:07:24 -05:00
zhengbin
1d1dda8ca8 dm snapshot: use true/false for bool variable
Fixes coccicheck warning:

drivers/md/dm-snap.c:1064:3-18: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-snap.c:1152:1-16: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-snap.c:1317:1-16: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 12:07:17 -05:00
zhengbin
67b92d979b dm bio prison v2: use true/false for bool variable
Fixes coccicheck warning:

drivers/md/dm-bio-prison-v2.c:327:2-22: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 12:07:08 -05:00
zhengbin
4ecc508190 dm mpath: use true/false for bool variable
Fixes coccicheck warning:

drivers/md/dm-mpath.c:1447:2-13: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 12:06:56 -05:00
Dmitry Fomichev
b399629503 dm zoned: support zone sizes smaller than 128MiB
dm-zoned is observed to log failed kernel assertions and not work
correctly when operating against a device with a zone size smaller
than 128MiB (e.g. 32768 bits per 4K block). The reason is that the
bitmap size per zone is calculated as zero with such a small zone
size. Fix this problem and also make the code related to zone bitmap
management be able to handle per zone bitmaps smaller than a single
block.

A dm-zoned-tools patch is required to properly format dm-zoned devices
with zone sizes smaller than 128MiB.

Fixes: 3b1a94c88b ("dm zoned: drive-managed zoned block device target")
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 11:43:38 -05:00
Heinz Mauelshagen
43f3952a51 dm raid: table line rebuild status fixes
raid_status() wasn't emitting rebuild flags on the table line properly
because the rdev number was not yet set properly; index raid component
devices array directly to solve.

Also fix wrong argument count on emitted table line caused by 1 too
many rebuild/write_mostly argument and consider any journal_(dev|mode)
pairs.

Link: https://bugzilla.redhat.com/1782045
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 11:43:37 -05:00
Bryan Gurney
88e7cafdca dm dust: change ret to r in dust_map_write
In the dust_map_write() function, change the return code variable
"ret" to "r", to match the convention of the other device-mapper
targets.

Signed-off-by: Bryan Gurney <bgurney@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 11:43:36 -05:00
Linus Torvalds
f1fcd7786e for-linus-20191212
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl3y54EQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpqJuD/93LZmzS5UEWrNLkRaAaCyAy40MPxuXRZEp
 42yk7cvAT4OcCr+W6nkAgG6IHGRXOz8QvOzt0P5/HfugpNlB2oz5a/6+TiTtcZTt
 YNt0Z4yuBMU5SXIIxc3lUMcJGxslzOr+L+9ZXD4u5UqIdG1fSrECAexSCrlmmTwu
 Fx02TakDc/bbUYDfLAQD1+/Z066rp1ZWDkjXqA4kUvbFzt8F7qEOc1Evq47SuR7d
 Iw0bM3LVASXwTq2lRc1bFFL2glku6wwkccjwdyjSrQmK4+8LhF396fQGtXuj0Mrs
 OzuWhaOoGhan7dpj1D8e4tqugflQy9rv9bcy6Z9PjBY+VauuFdgPr3iFcwPaPbXm
 17ir4y7xJJxXlhZl/Bn06KIB2h+nLWDIaundFys5JnMmTiZvWIgSJ6Q3gWtMxgfH
 zWZLMw/UtRAmjHhLqvGsMaBTfgKX5ATpMbfGeZeXheVtVaOgGTunXunT56o7oRHB
 q4XWZqbydsYyHBUhgSzhBr03i67wbotxtebqg9VZ0UD8XM4iM8Kor/DleK03oUqD
 DsltKF66NAGNeOcV3TNzJuXHyF6S/vZdO7JdFHY29+pdljoTj5GB88+W9CbhwQRe
 WiKVpq7sAe/bh0wtqrD+QCByjSNSVU62kVgRhfqms47804j/vNqNvOKaC5UWTd0I
 2LG4jfSbeg==
 =hmxJ
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-20191212' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - stable fix for the bi_size overflow. Not a corruption issue, but a
   case wher we could merge but disallowed (Andreas)

 - NVMe pull request via Keith, with various fixes.

 - MD pull request from Song.

 - Merge window regression fix for the rq passthrough stats (Logan)

 - Remove unused blkcg_drain_queue() function (Guoqing)

* tag 'for-linus-20191212' of git://git.kernel.dk/linux-block:
  blk-cgroup: remove blkcg_drain_queue
  block: fix NULL pointer dereference in account statistics with IDE
  md: make sure desc_nr less than MD_SB_DISKS
  md: raid1: check rdev before reference in raid1_sync_request func
  raid5: need to set STRIPE_HANDLE for batch head
  block: fix "check bi_size overflow before merge"
  nvme/pci: Fix read queue count
  nvme/pci Limit write queue sizes to possible cpus
  nvme/pci: Fix write and poll queue types
  nvme/pci: Remove last_cq_head
  nvme: Namepace identification descriptor list is optional
  nvme-fc: fix double-free scenarios on hw queues
  nvme: else following return is not needed
  nvme: add error message on mismatching controller ids
  nvme_fc: add module to ops template to allow module references
  nvmet-loop: Avoid preallocating big SGL for data
  nvme-fc: Avoid preallocating big SGL for data
  nvme-rdma: Avoid preallocating big SGL for data
2019-12-13 14:27:19 -08:00
Linus Torvalds
15da849c91 - Fix DM multipath by restoring full path selector functionality for
bio-based configurations that don't haave a SCSI device handler.
 
 - Fix dm-btree removal to ensure non-root btree nodes have at least
   (max_entries / 3) entries.  This resolves userspace thin_check
   utility's report of "too few entries in btree_node".
 
 - Fix both the DM thin-provisioning and dm-clone targets to properly
   flush the data device prior to metadata commit.  This resolves the
   potential for inconsistency across a power loss event when the data
   device has a volatile writeback cache.
 
 - Small documentation fixes to dm-clone and dm-integrity.
 -----BEGIN PGP SIGNATURE-----
 
 iQFHBAABCAAxFiEEJfWUX4UqZ4x1O2wixSPxCi2dA1oFAl3yU6sTHHNuaXR6ZXJA
 cmVkaGF0LmNvbQAKCRDFI/EKLZ0DWvO9B/0dsIxL09sWSHPe+wuzy7WXAOCHVm04
 27dloxNzgXGFT5ftvU+JpLParOtDfJ2ral2BVGExjGzMs4QP8ZLrn5UuTFuR7nXi
 FDaypaCelRsh1/204bKDgb22vaZIAZFu7Rz2YsAzWqpCJZDjN5cgy9xz4GmCvXRt
 R13Qq8Dia4scR/y+xCkm5s4wH2xGz1CDmpSPzbLTpTfkMfY5yzp6Gzaipj4Fwq78
 dDERNZNuabVr2o8mt8OGd/s1h4QtiJps1J8NV2He5C3Bf8daaFVkHDCl75+P2KQC
 ++VaIS/l1TfcOyDJmoztg7w2gmLkTxEskVpN/UQD/Ut9D5m7P9S7uaQg
 =6t9f
 -----END PGP SIGNATURE-----

Merge tag 'for-5.5/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Fix DM multipath by restoring full path selector functionality for
   bio-based configurations that don't haave a SCSI device handler.

 - Fix dm-btree removal to ensure non-root btree nodes have at least
   (max_entries / 3) entries. This resolves userspace thin_check
   utility's report of "too few entries in btree_node".

 - Fix both the DM thin-provisioning and dm-clone targets to properly
   flush the data device prior to metadata commit. This resolves the
   potential for inconsistency across a power loss event when the data
   device has a volatile writeback cache.

 - Small documentation fixes to dm-clone and dm-integrity.

* tag 'for-5.5/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  docs: dm-integrity: remove reference to ARC4
  dm thin: Flush data device before committing metadata
  dm thin metadata: Add support for a pre-commit callback
  dm clone: Flush destination device before committing metadata
  dm clone metadata: Use a two phase commit
  dm clone metadata: Track exact changes per transaction
  dm btree: increase rebalance threshold in __rebalance2()
  dm: add dm-clone to the documentation index
  dm mpath: remove harmful bio-based optimization
2019-12-13 14:13:15 -08:00
Yufen Yu
3b7436cc94 md: make sure desc_nr less than MD_SB_DISKS
For super_90_load, we need to make sure 'desc_nr' less
than MD_SB_DISKS, avoiding invalid memory access of 'sb->disks'.

Fixes: 228fc7d76d ("md: avoid invalid memory access for array sb->dev_roles")
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-12-11 10:38:08 -08:00
Zhiqiang Liu
028288df63 md: raid1: check rdev before reference in raid1_sync_request func
In raid1_sync_request func, rdev should be checked before reference.

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-12-11 10:36:13 -08:00
Guoqing Jiang
a7ede3d168 raid5: need to set STRIPE_HANDLE for batch head
With commit 6ce220dd2f ("raid5: don't set
STRIPE_HANDLE to stripe which is in batch list"), we don't want to set
STRIPE_HANDLE flag for sh which is already in batch list.

However, the stripe which is the head of batch list should set this flag,
otherwise panic could happen inside init_stripe at BUG_ON(sh->batch_head),
it is reproducible with raid5 on top of nvdimm devices per Xiao oberserved.

Thanks for Xiao's effort to verify the change.

Fixes: 6ce220dd2f ("raid5: don't set STRIPE_HANDLE to stripe which is in batch list")
Reported-by: Xiao Ni <xni@redhat.com>
Tested-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-12-11 10:12:09 -08:00
Pankaj Bharadiya
c593642c8b treewide: Use sizeof_field() macro
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().

This patch is generated using following script:

EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"

git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do

	if [[ "$file" =~ $EXCLUDE_FILES ]]; then
		continue
	fi
	sed -i  -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
2019-12-09 10:36:44 -08:00
Nikos Tsironis
694cfe7f31 dm thin: Flush data device before committing metadata
The thin provisioning target maintains per thin device mappings that map
virtual blocks to data blocks in the data device.

When we write to a shared block, in case of internal snapshots, or
provision a new block, in case of external snapshots, we copy the shared
block to a new data block (COW), update the mapping for the relevant
virtual block and then issue the write to the new data block.

Suppose the data device has a volatile write-back cache and the
following sequence of events occur:

1. We write to a shared block
2. A new data block is allocated
3. We copy the shared block to the new data block using kcopyd (COW)
4. We insert the new mapping for the virtual block in the btree for that
   thin device.
5. The commit timeout expires and we commit the metadata, that now
   includes the new mapping from step (4).
6. The system crashes and the data device's cache has not been flushed,
   meaning that the COWed data are lost.

The next time we read that virtual block of the thin device we read it
from the data block allocated in step (2), since the metadata have been
successfully committed. The data are lost due to the crash, so we read
garbage instead of the old, shared data.

This has the following implications:

1. In case of writes to shared blocks, with size smaller than the pool's
   block size (which means we first copy the whole block and then issue
   the smaller write), we corrupt data that the user never touched.

2. In case of writes to shared blocks, with size equal to the device's
   logical block size, we fail to provide atomic sector writes. When the
   system recovers the user will read garbage from that sector instead
   of the old data or the new data.

3. Even for writes to shared blocks, with size equal to the pool's block
   size (overwrites), after the system recovers, the written sectors
   will contain garbage instead of a random mix of sectors containing
   either old data or new data, thus we fail again to provide atomic
   sectors writes.

4. Even when the user flushes the thin device, because we first commit
   the metadata and then pass down the flush, the same risk for
   corruption exists (if the system crashes after the metadata have been
   committed but before the flush is passed down to the data device.)

The only case which is unaffected is that of writes with size equal to
the pool's block size and with the FUA flag set. But, because FUA writes
trigger metadata commits, this case can trigger the corruption
indirectly.

Moreover, apart from internal and external snapshots, the same issue
exists for newly provisioned blocks, when block zeroing is enabled.
After the system recovers the provisioned blocks might contain garbage
instead of zeroes.

To solve this and avoid the potential data corruption we flush the
pool's data device **before** committing its metadata.

This ensures that the data blocks of any newly inserted mappings are
properly written to non-volatile storage and won't be lost in case of a
crash.

Cc: stable@vger.kernel.org
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-06 11:46:16 -05:00
Nikos Tsironis
ecda7c0280 dm thin metadata: Add support for a pre-commit callback
Add support for one pre-commit callback which is run right before the
metadata are committed.

This allows the thin provisioning target to run a callback before the
metadata are committed and is required by the next commit.

Cc: stable@vger.kernel.org
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-05 17:05:24 -05:00
Nikos Tsironis
8b3fd1f53a dm clone: Flush destination device before committing metadata
dm-clone maintains an on-disk bitmap which records which regions are
valid in the destination device, i.e., which regions have already been
hydrated, or have been written to directly, via user I/O.

Setting a bit in the on-disk bitmap meas the corresponding region is
valid in the destination device and we redirect all I/O regarding it to
the destination device.

Suppose the destination device has a volatile write-back cache and the
following sequence of events occur:

1. A region gets hydrated, either through the background hydration or
   because it was written to directly, via user I/O.

2. The commit timeout expires and we commit the metadata, marking that
   region as valid in the destination device.

3. The system crashes and the destination device's cache has not been
   flushed, meaning the region's data are lost.

The next time we read that region we read it from the destination
device, since the metadata have been successfully committed, but the
data are lost due to the crash, so we read garbage instead of the old
data.

This has several implications:

1. In case of background hydration or of writes with size smaller than
   the region size (which means we first copy the whole region and then
   issue the smaller write), we corrupt data that the user never
   touched.

2. In case of writes with size equal to the device's logical block size,
   we fail to provide atomic sector writes. When the system recovers the
   user will read garbage from the sector instead of the old data or the
   new data.

3. In case of writes without the FUA flag set, after the system
   recovers, the written sectors will contain garbage instead of a
   random mix of sectors containing either old data or new data, thus we
   fail again to provide atomic sector writes.

4. Even when the user flushes the dm-clone device, because we first
   commit the metadata and then pass down the flush, the same risk for
   corruption exists (if the system crashes after the metadata have been
   committed but before the flush is passed down).

The only case which is unaffected is that of writes with size equal to
the region size and with the FUA flag set. But, because FUA writes
trigger metadata commits, this case can trigger the corruption
indirectly.

To solve this and avoid the potential data corruption we flush the
destination device **before** committing the metadata.

This ensures that any freshly hydrated regions, for which we commit the
metadata, are properly written to non-volatile storage and won't be lost
in case of a crash.

Fixes: 7431b7835f ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-05 17:05:23 -05:00
Nikos Tsironis
8fdbfe8d16 dm clone metadata: Use a two phase commit
Split the metadata commit in two parts:

1. dm_clone_metadata_pre_commit(): Prepare the current transaction for
   committing. After this is called, all subsequent metadata updates,
   done through either dm_clone_set_region_hydrated() or
   dm_clone_cond_set_range(), will be part of the next transaction.

2. dm_clone_metadata_commit(): Actually commit the current transaction
   to disk and start a new transaction.

This is required by the following commit. It allows dm-clone to flush
the destination device after step (1) to ensure that all freshly
hydrated regions, for which we are updating the metadata, are properly
written to non-volatile storage and won't be lost in case of a crash.

Fixes: 7431b7835f ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-05 15:27:54 -05:00
Nikos Tsironis
e6a505f3f9 dm clone metadata: Track exact changes per transaction
Extend struct dirty_map with a second bitmap which tracks the exact
regions that were hydrated during the current metadata transaction.

Moreover, fix __flush_dmap() to only commit the metadata of the regions
that were hydrated during the current transaction.

This is required by the following commits to fix a data corruption bug.

Fixes: 7431b7835f ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-05 15:27:53 -05:00