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: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

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: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

It actually means create here, so fix the typo.
Reported-by: NSong Liu <liu.song.a23@gmail.com>
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

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: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

We can use "cnt" directly to update conf->worker_cnt_per_group
if alloc_thread_groups returns 0.
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

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: NZhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

For super_90_load, we need to make sure 'desc_nr' less
than MD_SB_DISKS, avoiding invalid memory access of 'sb->disks'.

Fixes: 228fc7d7 ("md: avoid invalid memory access for array sb->dev_roles")
Signed-off-by: NYufen Yu <yuyufen@huawei.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

In raid1_sync_request func, rdev should be checked before reference.
Signed-off-by: NZhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

With commit 6ce220dd ("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: 6ce220dd ("raid5: don't set STRIPE_HANDLE to stripe which is in batch list")
Reported-by: NXiao Ni <xni@redhat.com>
Tested-by: NXiao Ni <xni@redhat.com>
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

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: NPankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.comCo-developed-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net

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: NNikos Tsironis <ntsironis@arrikto.com>
Acked-by: NJoe Thornber <ejt@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: NNikos Tsironis <ntsironis@arrikto.com>
Acked-by: NJoe Thornber <ejt@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: 7431b783 ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: NNikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: 7431b783 ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: NNikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: 7431b783 ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: NNikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: NHou Tao <houtao1@huawei.com>
Acked-by: NJoe Thornber <ejt@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: NJavier González <javier@javigon.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: 8d47e659 ("dm mpath: remove unnecessary NVMe branching in favor of scsi_dh checks")
Cc: stable@vger.kernel.org
Reported-by: NDrew Hastings <dhastings@crucialwebhost.com>
Suggested-by: NMartin Wilck <mwilck@suse.de>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

This reverts commit a1b89132.

Revert required hand-patching due to subsequent changes that were
applied since commit a1b89132.

Requires: ed0302e8 ("dm crypt: make workqueue names device-specific")
Cc: stable@vger.kernel.org
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=199857Reported-by: NVito Caputo <vcaputo@pengaru.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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 c0e0954e.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NJeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

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: NMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@redhat.com>

As it is consistent with prefixes of other write life time hints.
Signed-off-by: NEugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

As it is consistent with prefixes of other write life time hints.
Signed-off-by: NEugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>

None of the exported bcache symbols are actually used anywhere.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There is no block directory this file needs includes from.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NChristian Balzer <chibi@gol.com>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

bcache_allocator can call the following:

 bch_allocator_thread()
  -> bch_prio_write()
     -> bch_bucket_alloc()
        -> wait on &ca->set->bucket_wait

But the wake up event on bucket_wait is supposed to come from
bch_allocator_thread() itself => deadlock:

[ 1158.490744] INFO: task bcache_allocato:15861 blocked for more than 10 seconds.
[ 1158.495929]       Not tainted 5.3.0-050300rc3-generic #201908042232
[ 1158.500653] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1158.504413] bcache_allocato D    0 15861      2 0x80004000
[ 1158.504419] Call Trace:
[ 1158.504429]  __schedule+0x2a8/0x670
[ 1158.504432]  schedule+0x2d/0x90
[ 1158.504448]  bch_bucket_alloc+0xe5/0x370 [bcache]
[ 1158.504453]  ? wait_woken+0x80/0x80
[ 1158.504466]  bch_prio_write+0x1dc/0x390 [bcache]
[ 1158.504476]  bch_allocator_thread+0x233/0x490 [bcache]
[ 1158.504491]  kthread+0x121/0x140
[ 1158.504503]  ? invalidate_buckets+0x890/0x890 [bcache]
[ 1158.504506]  ? kthread_park+0xb0/0xb0
[ 1158.504510]  ret_from_fork+0x35/0x40

Fix by making the call to bch_prio_write() non-blocking, so that
bch_allocator_thread() never waits on itself.

Moreover, make sure to wake up the garbage collector thread when
bch_prio_write() is failing to allocate buckets.

BugLink: https://bugs.launchpad.net/bugs/1784665
BugLink: https://bugs.launchpad.net/bugs/1796292Signed-off-by: NAndrea Righi <andrea.righi@canonical.com>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch adds simple code comments for bch_keylist_pop() and
bch_keylist_pop_front() in bset.c, to make the code more easier to
be understand.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

In request.c:bch_data_insert_keys(), there is code comment for a piece
of dead code. This patch deletes the dead code and its code comment
since they are useless in practice.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Previous code only returns "Not a bcache superblock" for both bcache
super block offset and magic error. This patch addss more accurate error
messages,
- for super block unmatched offset:
  "Not a bcache superblock (bad offset)"
- for super block unmatched magic number:
  "Not a bcache superblock (bad magic)"
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Commit cafe5635 ("bcache: A block layer cache") leads to the
following static checker warning:

    ./drivers/md/bcache/super.c:770 bcache_device_free()
    warn: variable dereferenced before check 'd->disk' (see line 766)

drivers/md/bcache/super.c
   762  static void bcache_device_free(struct bcache_device *d)
   763  {
   764          lockdep_assert_held(&bch_register_lock);
   765
   766          pr_info("%s stopped", d->disk->disk_name);
                                      ^^^^^^^^^
Unchecked dereference.

   767
   768          if (d->c)
   769                  bcache_device_detach(d);
   770          if (d->disk && d->disk->flags & GENHD_FL_UP)
                    ^^^^^^^
Check too late.

   771                  del_gendisk(d->disk);
   772          if (d->disk && d->disk->queue)
   773                  blk_cleanup_queue(d->disk->queue);
   774          if (d->disk) {
   775                  ida_simple_remove(&bcache_device_idx,
   776                                    first_minor_to_idx(d->disk->first_minor));
   777                  put_disk(d->disk);
   778          }
   779

It is not 100% sure that the gendisk struct of bcache device will always
be there, the warning makes sense when there is problem in block core.

This patch tries to remove the static checking warning by checking
d->disk to avoid NULL pointer deferences.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch fix a lost wake-up problem caused by the race between
mca_cannibalize_lock and bch_cannibalize_unlock.

Consider two processes, A and B. Process A is executing
mca_cannibalize_lock, while process B takes c->btree_cache_alloc_lock
and is executing bch_cannibalize_unlock. The problem happens that after
process A executes cmpxchg and will execute prepare_to_wait. In this
timeslice process B executes wake_up, but after that process A executes
prepare_to_wait and set the state to TASK_INTERRUPTIBLE. Then process A
goes to sleep but no one will wake up it. This problem may cause bcache
device to dead.
Signed-off-by: NGuoju Fang <fangguoju@gmail.com>
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Fifo structure journal.pin is implemented by a cycle buffer, if the back
index reaches highest location of the cycle buffer, it will be swapped
to 0. Once the swapping happens, it means a smaller fifo index might be
associated to a newer journal entry. So the btree node with oldest
journal entry won't be selected in bch_btree_leaf_dirty() to reference
the dirty B+tree leaf node. This problem may cause bcache journal won't
protect unflushed oldest B+tree dirty leaf node in power failure, and
this B+tree leaf node is possible to beinconsistent after reboot from
power failure.

This patch fixes the fifo index comparing logic in journal_pin_cmp(),
to avoid potential corrupted B+tree leaf node when the back index of
journal pin is swapped.
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Avoid the need to allocate a potentially large array of struct blk_zone
in the block layer by switching the ->report_zones method interface to
a callback model. Now the caller simply supplies a callback that is
executed on each reported zone, and private data for it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NMike Snitzer <snitzer@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

No known partitioning tool supports zoned block devices, especially the
host managed flavor with strong sequential write constraints.
Furthermore, there are also no known user nor use cases for partitioned
zoned block devices.

This patch removes partition device creation for zoned block devices,
which allows simplifying the processing of zone commands for zoned
block devices. A warning is added if a partition table is found on the
device.

For report zones operations no zone sector information remapping is
necessary anymore, simplifying the code. Of note is that remapping of
zone reports for DM targets is still necessary as done by
dm_remap_zone_report().

Similarly, remaping of a zone reset bio is not necessary anymore.
Testing for the applicability of the zone reset all request also becomes
simpler and only needs to check that the number of sectors of the
requested zone range is equal to the disk capacity.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>