Commit Graph

6048 Commits

Author SHA1 Message Date
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
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
Linus Torvalds
f1fcd7786e for-linus-20191212
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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.
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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
Hou Tao
474e559567 dm btree: increase rebalance threshold in __rebalance2()
We got the following warnings from thin_check during thin-pool setup:

  $ thin_check /dev/vdb
  examining superblock
  examining devices tree
    missing devices: [1, 84]
      too few entries in btree_node: 41, expected at least 42 (block 138, max_entries = 126)
  examining mapping tree

The phenomenon is the number of entries in one node of details_info tree is
less than (max_entries / 3). And it can be easily reproduced by the following
procedures:

  $ new a thin pool
  $ presume the max entries of details_info tree is 126
  $ new 127 thin devices (e.g. 1~127) to make the root node being full
    and then split
  $ remove the first 43 (e.g. 1~43) thin devices to make the children
    reblance repeatedly
  $ stop the thin pool
  $ thin_check

The root cause is that the B-tree removal procedure in __rebalance2()
doesn't guarantee the invariance: the minimal number of entries in
non-root node should be >= (max_entries / 3).

Simply fix the problem by increasing the rebalance threshold to
make sure the number of entries in each child will be greater
than or equal to (max_entries / 3 + 1), so no matter which
child is used for removal, the number will still be valid.

Cc: stable@vger.kernel.org
Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-05 15:27:52 -05:00
Christoph Hellwig
ae58954d87 block: don't handle bio based drivers in blk_revalidate_disk_zones
bio based drivers only need to update q->nr_zones.  Do that manually
instead of overloading blk_revalidate_disk_zones to keep that function
simpler for the next round of changes that will rely even more on the
request based functionality.

Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-12-03 08:51:25 -07:00
Christoph Hellwig
9b38bb4b1e block: simplify blkdev_nr_zones
Simplify the arguments to blkdev_nr_zones by passing a gendisk instead
of the block_device and capacity.  This also removes the need for
__blkdev_nr_zones as all callers are outside the fast path and can
deal with the additional branch.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-12-03 08:51:24 -07:00
Mike Snitzer
dbaf971c9c dm mpath: remove harmful bio-based optimization
Removes the branching for edge-case where no SCSI device handler
exists.  The __map_bio_fast() method was far too limited, by only
selecting a new pathgroup or path IFF there was a path failure, fix this
be eliminating it in favor of __map_bio().  __map_bio()'s extra SCSI
device handler specific MPATHF_PG_INIT_REQUIRED test is not in the fast
path anyway.

This change restores full path selector functionality for bio-based
configurations that don't haave a SCSI device handler.  But it should be
noted that the path selectors do have an impact on performance for
certain networks that are extremely fast (and don't require frequent
switching).

Fixes: 8d47e65948 ("dm mpath: remove unnecessary NVMe branching in favor of scsi_dh checks")
Cc: stable@vger.kernel.org
Reported-by: Drew Hastings <dhastings@crucialwebhost.com>
Suggested-by: Martin Wilck <mwilck@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-26 10:22:46 -05:00
Linus Torvalds
eeee2827ae - Fix DM core to disallow stacking request-based DM on partitions.
- Fix DM raid target to properly resync raidset even if bitmap needed
   additional pages.
 
 - Fix DM crypt performance regression due to use of WQ_HIGHPRI for the
   IO and crypt workqueues.
 
 - Fix DM integrity metadata layout that was aligned on 128K boundary
   rather than the intended 4K boundary (removes 124K of wasted space for
   each metadata block).
 
 - Improve the DM thin, cache and clone targets to use spin_lock_irq
   rather than spin_lock_irqsave where possible.
 
 - Fix DM thin single thread performance that was lost due to needless
   workqueue wakeups.
 
 - Fix DM zoned target performance that was lost due to excessive backing
   device checks.
 
 - Add ability to trigger write failure with the DM dust test target.
 
 - Fix whitespace indentation in drivers/md/Kconfig.
 
 - Various smalls fixes and cleanups (e.g. use struct_size, fix
   uninitialized variable, variable renames, etc).
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Merge tag 'for-5.5/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 to disallow stacking request-based DM on partitions.

 - Fix DM raid target to properly resync raidset even if bitmap needed
   additional pages.

 - Fix DM crypt performance regression due to use of WQ_HIGHPRI for the
   IO and crypt workqueues.

 - Fix DM integrity metadata layout that was aligned on 128K boundary
   rather than the intended 4K boundary (removes 124K of wasted space
   for each metadata block).

 - Improve the DM thin, cache and clone targets to use spin_lock_irq
   rather than spin_lock_irqsave where possible.

 - Fix DM thin single thread performance that was lost due to needless
   workqueue wakeups.

 - Fix DM zoned target performance that was lost due to excessive
   backing device checks.

 - Add ability to trigger write failure with the DM dust test target.

 - Fix whitespace indentation in drivers/md/Kconfig.

 - Various smalls fixes and cleanups (e.g. use struct_size, fix
   uninitialized variable, variable renames, etc).

* tag 'for-5.5/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (22 commits)
  Revert "dm crypt: use WQ_HIGHPRI for the IO and crypt workqueues"
  dm: Fix Kconfig indentation
  dm thin: wakeup worker only when deferred bios exist
  dm integrity: fix excessive alignment of metadata runs
  dm raid: Remove unnecessary negation of a shift in raid10_format_to_md_layout
  dm zoned: reduce overhead of backing device checks
  dm dust: add limited write failure mode
  dm dust: change ret to r in dust_map_read and dust_map
  dm dust: change result vars to r
  dm cache: replace spin_lock_irqsave with spin_lock_irq
  dm bio prison: replace spin_lock_irqsave with spin_lock_irq
  dm thin: replace spin_lock_irqsave with spin_lock_irq
  dm clone: add bucket_lock_irq/bucket_unlock_irq helpers
  dm clone: replace spin_lock_irqsave with spin_lock_irq
  dm writecache: handle REQ_FUA
  dm writecache: fix uninitialized variable warning
  dm stripe: use struct_size() in kmalloc()
  dm raid: streamline rs_get_progress() and its raid_status() caller side
  dm raid: simplify rs_setup_recovery call chain
  dm raid: to ensure resynchronization, perform raid set grow in preresume
  ...
2019-11-25 11:53:26 -08:00
Linus Torvalds
464a47f45d for-5.5/zoned-20191122
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Merge tag 'for-5.5/zoned-20191122' of git://git.kernel.dk/linux-block

Pull zoned block device update from Jens Axboe:
 "Enhancements and improvements to the zoned device support"

* tag 'for-5.5/zoned-20191122' of git://git.kernel.dk/linux-block:
  scsi: sd_zbc: Remove set but not used variable 'buflen'
  block: rework zone reporting
  scsi: sd_zbc: Cleanup sd_zbc_alloc_report_buffer()
  null_blk: Add zone_nr_conv to features
  null_blk: clean up report zones
  null_blk: clean up the block device operations
  block: Remove partition support for zoned block devices
  block: Simplify report zones execution
  block: cleanup the !zoned case in blk_revalidate_disk_zones
  block: Enhance blk_revalidate_disk_zones()
2019-11-25 11:22:37 -08:00
Linus Torvalds
2d53943090 for-5.5/drivers-20191121
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Merge tag 'for-5.5/drivers-20191121' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Here are the main block driver updates for 5.5. Nothing major in here,
  mostly just fixes. This contains:

   - a set of bcache changes via Coly

   - MD changes from Song

   - loop unmap write-zeroes fix (Darrick)

   - spelling fixes (Geert)

   - zoned additions cleanups to null_blk/dm (Ajay)

   - allow null_blk online submit queue changes (Bart)

   - NVMe changes via Keith, nothing major here either"

* tag 'for-5.5/drivers-20191121' of git://git.kernel.dk/linux-block: (56 commits)
  Revert "bcache: fix fifo index swapping condition in journal_pin_cmp()"
  drivers/md/raid5-ppl.c: use the new spelling of RWH_WRITE_LIFE_NOT_SET
  drivers/md/raid5.c: use the new spelling of RWH_WRITE_LIFE_NOT_SET
  bcache: don't export symbols
  bcache: remove the extra cflags for request.o
  bcache: at least try to shrink 1 node in bch_mca_scan()
  bcache: add idle_max_writeback_rate sysfs interface
  bcache: add code comments in bch_btree_leaf_dirty()
  bcache: fix deadlock in bcache_allocator
  bcache: add code comment bch_keylist_pop() and bch_keylist_pop_front()
  bcache: deleted code comments for dead code in bch_data_insert_keys()
  bcache: add more accurate error messages in read_super()
  bcache: fix static checker warning in bcache_device_free()
  bcache: fix a lost wake-up problem caused by mca_cannibalize_lock
  bcache: fix fifo index swapping condition in journal_pin_cmp()
  md/raid10: prevent access of uninitialized resync_pages offset
  md: avoid invalid memory access for array sb->dev_roles
  md/raid1: avoid soft lockup under high load
  null_blk: add zone open, close, and finish support
  dm: add zone open, close and finish support
  ...
2019-11-25 11:15:41 -08:00
Mike Snitzer
f612b2132d Revert "dm crypt: use WQ_HIGHPRI for the IO and crypt workqueues"
This reverts commit a1b89132dc.

Revert required hand-patching due to subsequent changes that were
applied since commit a1b89132dc.

Requires: ed0302e830 ("dm crypt: make workqueue names device-specific")
Cc: stable@vger.kernel.org
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=199857
Reported-by: Vito Caputo <vcaputo@pengaru.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-20 17:27:39 -05:00
Krzysztof Kozlowski
443633225e dm: Fix Kconfig indentation
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
	$ sed -e 's/^        /\t/' -i */Kconfig

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-20 10:35:31 -05:00
Jens Axboe
00b89892c8 Revert "bcache: fix fifo index swapping condition in journal_pin_cmp()"
Coly says:

"Guoju Fang talked to me today, he told me this change was unnecessary
and I was over-thought.

Then I realize fifo_idx() uses a mask to handle the array index overflow
condition, so the index swap in journal_pin_cmp() won't happen. And yes,
Guoju and Kent are correct.

Since you already applied this patch, can you please to remove this
patch from your for-next branch? This single patch does not break
thing, but it is unecessary at this moment."

This reverts commit c0e0954e90.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-18 08:35:47 -07:00
Jeffle Xu
d256d79627 dm thin: wakeup worker only when deferred bios exist
Single thread fio test (read, bs=4k, ioengine=libaio, iodepth=128,
numjobs=1) over dm-thin device has poor performance versus bare nvme
device.

Further investigation with perf indicates that queue_work_on() consumes
over 20% CPU time when doing IO over dm-thin device. The call stack is
as follows.

- 40.57% thin_map
    + 22.07% queue_work_on
    + 9.95% dm_thin_find_block
    + 2.80% cell_defer_no_holder
      1.91% inc_all_io_entry.isra.33.part.34
    + 1.78% bio_detain.isra.35

In cell_defer_no_holder(), wakeup_worker() is always called, no matter
whether the tc->deferred_bio_list list is empty or not. In single thread
IO model, this list is most likely empty. So skip waking up worker thread
if tc->deferred_bio_list list is empty.

Single thread IO performance improves from 448 MiB/s to 646 MiB/s (+44%)
once the needless wake_worker() calls are properly skipped.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-18 10:03:12 -05:00
Mikulas Patocka
d537858ac8 dm integrity: fix excessive alignment of metadata runs
Metadata runs are supposed to be aligned on 4k boundary (so that they work
efficiently with disks with 4k sectors). However, there was a programming
bug that makes them aligned on 128k boundary instead. The unused space is
wasted.

Fix this bug by providing a proper 4k alignment. In order to keep
existing volumes working, we introduce a new flag SB_FLAG_FIXED_PADDING
- when the flag is clear, we calculate the padding the old way. In order
to make sure that the old version cannot mount the volume created by the
new version, we increase superblock version to 4.

Also in order to not break with old integritysetup, we fix alignment
only if the parameter "fix_padding" is present when formatting the
device.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-15 14:49:16 -05:00
Eugene Syromiatnikov
0815ef3c01 drivers/md/raid5-ppl.c: use the new spelling of RWH_WRITE_LIFE_NOT_SET
As it is consistent with prefixes of other write life time hints.

Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-11-14 14:59:15 -08:00
Eugene Syromiatnikov
f1934892bd drivers/md/raid5.c: use the new spelling of RWH_WRITE_LIFE_NOT_SET
As it is consistent with prefixes of other write life time hints.

Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-11-14 14:59:15 -08:00
Christoph Hellwig
15fbb2312f bcache: don't export symbols
None of the exported bcache symbols are actually used anywhere.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-13 15:42:51 -07:00
Christoph Hellwig
651bbba57a bcache: remove the extra cflags for request.o
There is no block directory this file needs includes from.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-13 15:42:50 -07:00
Coly Li
9fcc34b1a6 bcache: at least try to shrink 1 node in bch_mca_scan()
In bch_mca_scan(), the number of shrinking btree node is calculated
by code like this,
	unsigned long nr = sc->nr_to_scan;

        nr /= c->btree_pages;
        nr = min_t(unsigned long, nr, mca_can_free(c));
variable sc->nr_to_scan is number of objects (here is bcache B+tree
nodes' number) to shrink, and pointer variable sc is sent from memory
management code as parametr of a callback.

If sc->nr_to_scan is smaller than c->btree_pages, after the above
calculation, variable 'nr' will be 0 and nothing will be shrunk. It is
frequeently observed that only 1 or 2 is set to sc->nr_to_scan and make
nr to be zero. Then bch_mca_scan() will do nothing more then acquiring
and releasing mutex c->bucket_lock.

This patch checkes whether nr is 0 after the above calculation, if 0
is the result then set 1 to variable 'n'. Then at least bch_mca_scan()
will try to shrink a single B+tree node.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-13 15:42:50 -07:00
Coly Li
c5fcdedcee bcache: add idle_max_writeback_rate sysfs interface
For writeback mode, if there is no regular I/O request for a while,
the writeback rate will be set to the maximum value (1TB/s for now).
This is good for most of the storage workload, but there are still
people don't what the maximum writeback rate in I/O idle time.

This patch adds a sysfs interface file idle_max_writeback_rate to
permit people to disable maximum writeback rate. Then the minimum
writeback rate can be advised by writeback_rate_minimum in the
bcache device's sysfs interface.

Reported-by: Christian Balzer <chibi@gol.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-13 15:42:50 -07:00
Coly Li
5dccefd3ea bcache: add code comments in bch_btree_leaf_dirty()
This patch adds code comments in bch_btree_leaf_dirty() to explain
why w->journal should always reference the eldest journal pin of
all the writing bkeys in the btree node. To make the bcache journal
code to be easier to be understood.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-13 15:42:50 -07:00