Commit graph

6258 commits

Author SHA1 Message Date
Christoph Hellwig 5a6c35f9af block: remove direct_make_request
Now that submit_bio_noacct has a decent blk-mq fast path there is no
more need for this bypass.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:24 -06:00
Christoph Hellwig ed00aabd5e block: rename generic_make_request to submit_bio_noacct
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:24 -06:00
Christoph Hellwig c62b37d96b block: move ->make_request_fn to struct block_device_operations
The make_request_fn is a little weird in that it sits directly in
struct request_queue instead of an operation vector.  Replace it with
a block_device_operations method called submit_bio (which describes much
better what it does).  Also remove the request_queue argument to it, as
the queue can be derived pretty trivially from the bio.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:24 -06:00
Christoph Hellwig f695ca3886 block: remove the request_queue argument from blk_queue_split
The queue can be trivially derived from the bio, so pass one less
argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:23 -06:00
Christoph Hellwig c4a59c4e5d dm: stop using ->queuedata
Instead of setting up the queuedata as well just use one private data
field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:23 -06:00
Christoph Hellwig 987a0ef88b bcache: stop setting ->queuedata
Nothing in bcache actually uses the ->queuedata field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:23 -06:00
Christoph Hellwig 4ef2c5c246 dm: use bio_uninit instead of bio_disassociate_blkg
bio_uninit is the proper API to clean up a BIO that has been allocated
on stack or inside a structure that doesn't come from the BIO allocator.
Switch dm to use that instead of bio_disassociate_blkg, which really is
an implementation detail.  Note that the bio_uninit calls are also moved
to the two callers of __send_empty_flush, so that they better pair with
the bio_init calls used to initialize them.

Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-29 09:09:07 -06:00
Christoph Hellwig 15f73f5b3e blk-mq: move failure injection out of blk_mq_complete_request
Move the call to blk_should_fake_timeout out of blk_mq_complete_request
and into the drivers, skipping call sites that are obvious error
handlers, and remove the now superflous blk_mq_force_complete_rq helper.
This ensures we don't keep injecting errors into completions that just
terminate the Linux request after the hardware has been reset or the
command has been aborted.

Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-24 09:15:57 -06:00
Coly Li 4b25bbf52a bcache: pr_info() format clean up in bcache_device_init()
scripts/checkpatch.pl reports following warning for patch
("bcache: check and adjust logical block size for backing devices"),
    WARNING: quoted string split across lines
    #146: FILE: drivers/md/bcache/super.c:896:
    +  pr_info("%s: sb/logical block size (%u) greater than page size "
    +	       "(%lu) falling back to device logical block size (%u)",

There are two things to fix up,
- The kernel message print should be in a single line.
- pr_info() won't automatically add new line since v5.8, a '\n' should
  be added.

This patch just does the above cleanup in bcache_device_init().

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-14 16:47:56 -06:00
Coly Li ee4a36f414 bcache: use delayed kworker fo asynchronous devices registration
This patch changes the asynchronous registration kworker to a delayed
kworker. There is probability queue_work() queues the async registration
kworker to the same CPU (even though very little), then the process
which writing sysfs interface to reigster bcache device may won't return
immeidately. queue_delayed_work() in this patch will delay 10 jiffies
before insert the kworker to run queue, which makes sure the registering
process may always returns to user space in time.

Fixes: 9e23ccf8f0 ("bcache: asynchronous devices registration")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-14 16:47:56 -06:00
Mauricio Faria de Oliveira dcacbc1242 bcache: check and adjust logical block size for backing devices
It's possible for a block driver to set logical block size to
a value greater than page size incorrectly; e.g. bcache takes
the value from the superblock, set by the user w/ make-bcache.

This causes a BUG/NULL pointer dereference in the path:

  __blkdev_get()
  -> set_init_blocksize() // set i_blkbits based on ...
     -> bdev_logical_block_size()
        -> queue_logical_block_size() // ... this value
  -> bdev_disk_changed()
     ...
     -> blkdev_readpage()
        -> block_read_full_page()
           -> create_page_buffers() // size = 1 << i_blkbits
              -> create_empty_buffers() // give size/take pointer
                 -> alloc_page_buffers() // return NULL
                 .. BUG!

Because alloc_page_buffers() is called with size > PAGE_SIZE,
thus it initializes head = NULL, skips the loop, return head;
then create_empty_buffers() gets (and uses) the NULL pointer.

This has been around longer than commit ad6bf88a6c ("block:
fix an integer overflow in logical block size"); however, it
increased the range of values that can trigger the issue.

Previously only 8k/16k/32k (on x86/4k page size) would do it,
as greater values overflow unsigned short to zero, and queue_
logical_block_size() would then use the default of 512.

Now the range with unsigned int is much larger, and users w/
the 512k value, which happened to be zero'ed previously and
work fine, started to hit this issue -- as the zero is gone,
and queue_logical_block_size() does return 512k (>PAGE_SIZE.)

Fix this by checking the bcache device's logical block size,
and if it's greater than page size, fallback to the backing/
cached device's logical page size.

This doesn't affect cache devices as those are still checked
for block/page size in read_super(); only the backing/cached
devices are not.

Apparently it's a regression from commit 2903381fce ("bcache:
Take data offset from the bdev superblock."), moving the check
into BCACHE_SB_VERSION_CDEV only. Now that we have superblocks
of backing devices out there with this larger value, we cannot
refuse to load them (i.e., have a similar check in _BDEV.)

Ideally perhaps bcache should use all values from the backing
device (physical/logical/io_min block size)? But for now just
fix the problematic case.

Test-case:

    # IMG=/root/disk.img
    # dd if=/dev/zero of=$IMG bs=1 count=0 seek=1G
    # DEV=$(losetup --find --show $IMG)
    # make-bcache --bdev $DEV --block 8k
      < see dmesg >

Before:

    # uname -r
    5.7.0-rc7

    [   55.944046] BUG: kernel NULL pointer dereference, address: 0000000000000000
    ...
    [   55.949742] CPU: 3 PID: 610 Comm: bcache-register Not tainted 5.7.0-rc7 #4
    ...
    [   55.952281] RIP: 0010:create_empty_buffers+0x1a/0x100
    ...
    [   55.966434] Call Trace:
    [   55.967021]  create_page_buffers+0x48/0x50
    [   55.967834]  block_read_full_page+0x49/0x380
    [   55.972181]  do_read_cache_page+0x494/0x610
    [   55.974780]  read_part_sector+0x2d/0xaa
    [   55.975558]  read_lba+0x10e/0x1e0
    [   55.977904]  efi_partition+0x120/0x5a6
    [   55.980227]  blk_add_partitions+0x161/0x390
    [   55.982177]  bdev_disk_changed+0x61/0xd0
    [   55.982961]  __blkdev_get+0x350/0x490
    [   55.983715]  __device_add_disk+0x318/0x480
    [   55.984539]  bch_cached_dev_run+0xc5/0x270
    [   55.986010]  register_bcache.cold+0x122/0x179
    [   55.987628]  kernfs_fop_write+0xbc/0x1a0
    [   55.988416]  vfs_write+0xb1/0x1a0
    [   55.989134]  ksys_write+0x5a/0xd0
    [   55.989825]  do_syscall_64+0x43/0x140
    [   55.990563]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [   55.991519] RIP: 0033:0x7f7d60ba3154
    ...

After:

    # uname -r
    5.7.0.bcachelbspgsz

    [   31.672460] bcache: bcache_device_init() bcache0: sb/logical block size (8192) greater than page size (4096) falling back to device logical block size (512)
    [   31.675133] bcache: register_bdev() registered backing device loop0

    # grep ^ /sys/block/bcache0/queue/*_block_size
    /sys/block/bcache0/queue/logical_block_size:512
    /sys/block/bcache0/queue/physical_block_size:8192

Reported-by: Ryan Finnie <ryan@finnie.org>
Reported-by: Sebastian Marsching <sebastian@marsching.com>
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-14 16:47:56 -06:00
Zhiqiang Liu be23e83733 bcache: fix potential deadlock problem in btree_gc_coalesce
coccicheck reports:
  drivers/md//bcache/btree.c:1538:1-7: preceding lock on line 1417

In btree_gc_coalesce func, if the coalescing process fails, we will goto
to out_nocoalesce tag directly without releasing new_nodes[i]->write_lock.
Then, it will cause a deadlock when trying to acquire new_nodes[i]->
write_lock for freeing new_nodes[i] before return.

btree_gc_coalesce func details as follows:
	if alloc new_nodes[i] fails:
		goto out_nocoalesce;
	// obtain new_nodes[i]->write_lock
	mutex_lock(&new_nodes[i]->write_lock)
	// main coalescing process
	for (i = nodes - 1; i > 0; --i)
		[snipped]
		if coalescing process fails:
			// Here, directly goto out_nocoalesce
			 // tag will cause a deadlock
			goto out_nocoalesce;
		[snipped]
	// release new_nodes[i]->write_lock
	mutex_unlock(&new_nodes[i]->write_lock)
	// coalesing succ, return
	return;
out_nocoalesce:
	btree_node_free(new_nodes[i])	// free new_nodes[i]
	// obtain new_nodes[i]->write_lock
	mutex_lock(&new_nodes[i]->write_lock);
	// set flag for reuse
	clear_bit(BTREE_NODE_dirty, &ew_nodes[i]->flags);
	// release new_nodes[i]->write_lock
	mutex_unlock(&new_nodes[i]->write_lock);

To fix the problem, we add a new tag 'out_unlock_nocoalesce' for
releasing new_nodes[i]->write_lock before out_nocoalesce tag. If
coalescing process fails, we will go to out_unlock_nocoalesce tag
for releasing new_nodes[i]->write_lock before free new_nodes[i] in
out_nocoalesce tag.

(Coly Li helps to clean up commit log format.)

Fixes: 2a285686c1 ("bcache: btree locking rework")
Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-14 16:47:56 -06:00
Masahiro Yamada a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Linus Torvalds b25c6644bf - Largest change for this cycle is the DM zoned target's metadata
version 2 feature that adds support for pairing regular block
   devices with a zoned device to ease performance impact associated
   with finite random zones of zoned device.  Changes came in 3
   batches: first prepared for and then added the ability to pair a
   single regular block device, second was a batch of fixes to improve
   zoned's reclaim heuristic, third removed the limitation of only
   adding a single additional regular block device to allow many
   devices.  Testing has shown linear scaling as more devices are
   added.
 
 - Add new emulated block size (ebs) target that emulates a smaller
   logical_block_size than a block device supports.  Primary use-case
   is to emulate "512e" devices that have 512 byte logical_block_size
   and 4KB physical_block_size.  This is useful to some legacy
   applications otherwise wouldn't be ablee to be used on 4K devices
   because they depend on issuing IO in 512 byte granularity.
 
 - Add discard interfaces to DM bufio.  First consumer of the interface
   is the dm-ebs target that makes heavy use of dm-bufio.
 
 - Fix DM crypt's block queue_limits stacking to not truncate
   logic_block_size.
 
 - Add Documentation for DM integrity's status line.
 
 - Switch DMDEBUG from a compile time config option to instead use
   dynamic debug via pr_debug.
 
 - Fix DM multipath target's hueristic for how it manages
   "queue_if_no_path" state internally.  DM multipath now avoids
   disabling "queue_if_no_path" unless it is actually needed (e.g. in
   response to configure timeout or explicit "fail_if_no_path"
   message).  This fixes reports of spurious -EIO being reported back
   to userspace application during fault tolerance testing with an NVMe
   backend.  Added various dynamic DMDEBUG messages to assist with
   debugging queue_if_no_path in the future.
 
 - Add a new DM multipath "Historical Service Time" Path Selector.
 
 - Fix DM multipath's dm_blk_ioctl() to switch paths on IO error.
 
 - Improve DM writecache target performance by using explicit
   cache flushing for target's single-threaded usecase and a small
   cleanup to remove unnecessary test in persistent_memory_claim.
 
 - Other small cleanups in DM core, dm-persistent-data, and DM integrity.
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Merge tag 'for-5.8/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - The largest change for this cycle is the DM zoned target's metadata
   version 2 feature that adds support for pairing regular block devices
   with a zoned device to ease the performance impact associated with
   finite random zones of zoned device.

   The changes came in three batches: the first prepared for and then
   added the ability to pair a single regular block device, the second
   was a batch of fixes to improve zoned's reclaim heuristic, and the
   third removed the limitation of only adding a single additional
   regular block device to allow many devices.

   Testing has shown linear scaling as more devices are added.

 - Add new emulated block size (ebs) target that emulates a smaller
   logical_block_size than a block device supports

   The primary use-case is to emulate "512e" devices that have 512 byte
   logical_block_size and 4KB physical_block_size. This is useful to
   some legacy applications that otherwise wouldn't be able to be used
   on 4K devices because they depend on issuing IO in 512 byte
   granularity.

 - Add discard interfaces to DM bufio. First consumer of the interface
   is the dm-ebs target that makes heavy use of dm-bufio.

 - Fix DM crypt's block queue_limits stacking to not truncate
   logic_block_size.

 - Add Documentation for DM integrity's status line.

 - Switch DMDEBUG from a compile time config option to instead use
   dynamic debug via pr_debug.

 - Fix DM multipath target's hueristic for how it manages
   "queue_if_no_path" state internally.

   DM multipath now avoids disabling "queue_if_no_path" unless it is
   actually needed (e.g. in response to configure timeout or explicit
   "fail_if_no_path" message).

   This fixes reports of spurious -EIO being reported back to userspace
   application during fault tolerance testing with an NVMe backend.
   Added various dynamic DMDEBUG messages to assist with debugging
   queue_if_no_path in the future.

 - Add a new DM multipath "Historical Service Time" Path Selector.

 - Fix DM multipath's dm_blk_ioctl() to switch paths on IO error.

 - Improve DM writecache target performance by using explicit cache
   flushing for target's single-threaded usecase and a small cleanup to
   remove unnecessary test in persistent_memory_claim.

 - Other small cleanups in DM core, dm-persistent-data, and DM
   integrity.

* tag 'for-5.8/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (62 commits)
  dm crypt: avoid truncating the logical block size
  dm mpath: add DM device name to Failing/Reinstating path log messages
  dm mpath: enhance queue_if_no_path debugging
  dm mpath: restrict queue_if_no_path state machine
  dm mpath: simplify __must_push_back
  dm zoned: check superblock location
  dm zoned: prefer full zones for reclaim
  dm zoned: select reclaim zone based on device index
  dm zoned: allocate zone by device index
  dm zoned: support arbitrary number of devices
  dm zoned: move random and sequential zones into struct dmz_dev
  dm zoned: per-device reclaim
  dm zoned: add metadata pointer to struct dmz_dev
  dm zoned: add device pointer to struct dm_zone
  dm zoned: allocate temporary superblock for tertiary devices
  dm zoned: convert to xarray
  dm zoned: add a 'reserved' zone flag
  dm zoned: improve logging messages for reclaim
  dm zoned: avoid unnecessary device recalulation for secondary superblock
  dm zoned: add debugging message for reading superblocks
  ...
2020-06-05 15:45:03 -07:00
Eric Biggers 64611a15ca dm crypt: avoid truncating the logical block size
queue_limits::logical_block_size got changed from unsigned short to
unsigned int, but it was forgotten to update crypt_io_hints() to use the
new type.  Fix it.

Fixes: ad6bf88a6c ("block: fix an integer overflow in logical block size")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:59 -04:00
Mike Snitzer 04867370ec dm mpath: add DM device name to Failing/Reinstating path log messages
When there are many DM multipath devices it really helps to have
additional context for which DM device a failed or reinstated path is
part of.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:58 -04:00
Mike Snitzer 4c3f48380f dm mpath: enhance queue_if_no_path debugging
Add more DMDEBUG that shows arguments passed and caller, and another
that shows state of related flags at end of queue_if_no_path().

Also add queue_if_no_path DMDEBUG to multipath_resume().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:57 -04:00
Mike Snitzer 553ec94cb4 dm mpath: restrict queue_if_no_path state machine
Do not allow saving disabled queue_if_no_path if already saved as
enabled; implies multiple suspends (which shouldn't ever happen).  Log
if this unlikely scenario is ever triggered.

Also, only write MPATHF_SAVED_QUEUE_IF_NO_PATH during presuspend or if
"fail_if_no_path" message.  MPATHF_SAVED_QUEUE_IF_NO_PATH is no longer
always modified, e.g.: even if queue_if_no_path()'s save_old_value
argument wasn't set.  This just implies a bit tighter control over
the management of MPATHF_SAVED_QUEUE_IF_NO_PATH.  Side-effect is
multipath_resume() doesn't reset MPATHF_QUEUE_IF_NO_PATH unless
MPATHF_SAVED_QUEUE_IF_NO_PATH was set (during presuspend); and at that
time the MPATHF_SAVED_QUEUE_IF_NO_PATH bit gets cleared.  So
MPATHF_SAVED_QUEUE_IF_NO_PATH's use is much more narrow in scope.

Last, but not least, do _not_ disable queue_if_no_path during noflush
suspend.  There is no need/benefit to saving off queue_if_no_path via
MPATHF_SAVED_QUEUE_IF_NO_PATH and clearing MPATHF_QUEUE_IF_NO_PATH for
noflush suspend -- by avoiding this needless queue_if_no_path flag
churn there is less potential for MPATHF_QUEUE_IF_NO_PATH to get lost.
Which avoids potential for IOs to be errored back up to userspace
during DM multipath's handling of path failures.

That said, this last change papers over a reported issue concerning
request-based dm-multipath's interaction with blk-mq, relative to
suspend and resume: multipath_endio is being called _before_
multipath_resume.  This should never happen if DM suspend's
blk_mq_quiesce_queue() + dm_wait_for_completion() is genuinely waiting
for all inflight blk-mq requests to complete.  Similarly:
drivers/md/dm.c:__dm_resume() clearly calls dm_table_resume_targets()
_before_ dm_start_queue()'s blk_mq_unquiesce_queue() is called.  If
the queue isn't even restarted until after multipath_resume(); the BIG
question that still needs answering is: how can multipath_end_io beat
multipath_resume in a race!?

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:56 -04:00
Mike Snitzer a862e4e215 dm mpath: simplify __must_push_back
Remove micro-optimization that infers device is between presuspend and
resume (was done purely to avoid call to dm_noflush_suspending, which
isn't expensive anyway).

Remove flags argument since they are no longer checked.

And remove must_push_back_bio() since it was simply a call to
__must_push_back().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:55 -04:00
Hannes Reinecke 27d49ac1dd dm zoned: check superblock location
When specifying several devices the superblock location must be
checked to ensure the devices are specified in the correct order.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:54 -04:00
Hannes Reinecke 2094045fe5 dm zoned: prefer full zones for reclaim
Prefer full zones when selecting the next zone for reclaim.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:54 -04:00
Hannes Reinecke 69875d443b dm zoned: select reclaim zone based on device index
per-device reclaim should select zones on that device only.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:53 -04:00
Hannes Reinecke 22c1ef66c4 dm zoned: allocate zone by device index
When allocating a zone, pass in an indicator on which device the zone
should be allocated; this increases performance for a multi-device
setup because reclaim will now allocate zones on the device for which
reclaim is running.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:52 -04:00
Hannes Reinecke 4dba12881f dm zoned: support arbitrary number of devices
Remove the hard-coded limit of two devices and support an unlimited
number of additional zoned devices.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:51 -04:00
Hannes Reinecke bd82fdabf1 dm zoned: move random and sequential zones into struct dmz_dev
Random and sequential zones should be part of the respective
device structure to make arbitration between devices possible.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:50 -04:00
Hannes Reinecke f97809aec5 dm zoned: per-device reclaim
Instead of having one reclaim workqueue for the entire set we should
be allocating a reclaim workqueue per device; doing so will reduce
contention and should boost performance for a multi-device setup.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:50 -04:00
Hannes Reinecke 18979819b5 dm zoned: add metadata pointer to struct dmz_dev
Add a metadata pointer within struct dmz_dev and use it as argument
for blkdev_report_zones() instead of the metadata itself.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:49 -04:00
Hannes Reinecke 8f22272af7 dm zoned: add device pointer to struct dm_zone
Add a pointer, to the containing device, within struct dm_zone and
kill dmz_zone_to_dev().

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:48 -04:00
Hannes Reinecke 5d2c74f3dd dm zoned: allocate temporary superblock for tertiary devices
Checking the tertiary superblock just consists of validating UUIDs,
crcs, and the generation number; it doesn't have contents which would
be required during the actual operation.

So allocate a temporary superblock when checking tertiary devices to
avoid having to store it together with the 'real' superblocks.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:47 -04:00
Hannes Reinecke a92fbc446d dm zoned: convert to xarray
The zones array is getting really large, and large arrays tend to
wreak havoc with the CPU caches.  So convert it to xarray to become
more cache friendly.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com> # fix leak in dmz_insert
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:46 -04:00
Hannes Reinecke aec67b4ffa dm zoned: add a 'reserved' zone flag
Instead of counting the number of reserved zones in dmz_free_zone(),
mark the zone as 'reserved' during allocation and simplify
dmz_free_zone().

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:46 -04:00
Hannes Reinecke c3ff479dde dm zoned: improve logging messages for reclaim
Instead of just reporting the errno, add some more verbose debugging
message in the reclaim path.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:45 -04:00
Hannes Reinecke 1565929b87 dm zoned: avoid unnecessary device recalulation for secondary superblock
The secondary superblock must reside on the same device as the primary
superblock, so there is no need to re-calculate the device.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:44 -04:00
Hannes Reinecke 35d0c96e42 dm zoned: add debugging message for reading superblocks
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:43 -04:00
Mikulas Patocka 334b4fc172 dm ebs: use dm_bufio_forget_buffers
Use dm_bufio_forget_buffers instead of a block-by-block loop that
calls dm_bufio_forget. dm_bufio_forget_buffers is faster than the loop
because it searches for used buffers using rb-tree.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:42 -04:00
Mikulas Patocka 33a180623b dm bufio: introduce forget_buffer_locked
Introduce a function forget_buffer_locked that forgets a range of
buffers. It is more efficient than calling forget_buffer in a loop.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:41 -04:00
Mikulas Patocka 88f878e588 dm bufio: clean up rbtree block ordering
dm-bufio uses unnatural ordering in the rb-tree - blocks with smaller
numbers were put to the right node and blocks with bigger numbers were
put to the left node.

Reverse that logic so that it's natural.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:41 -04:00
Mikulas Patocka a1c979f330 dm bufio: delete unused and inefficient dm_bufio_discard_buffers
There is no user for this interface.  If in future it is needed it can
be reimplemented to walk the rbtree of buffers instead of doing
block-by-block lookups.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-04 20:57:38 -04:00
Linus Torvalds bce159d734 for-5.8/drivers-2020-06-01
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Merge tag 'for-5.8/drivers-2020-06-01' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "On top of the core changes, here are the block driver changes for this
  merge window:

   - NVMe changes:
        - NVMe over Fibre Channel protocol updates, which also reach
          over to drivers/scsi/lpfc (James Smart)
        - namespace revalidation support on the target (Anthony
          Iliopoulos)
        - gcc zero length array fix (Arnd Bergmann)
        - nvmet cleanups (Chaitanya Kulkarni)
        - misc cleanups and fixes (me, Keith Busch, Sagi Grimberg)
        - use a SRQ per completion vector (Max Gurtovoy)
        - fix handling of runtime changes to the queue count (Weiping
          Zhang)
        - t10 protection information support for nvme-rdma and
          nvmet-rdma (Israel Rukshin and Max Gurtovoy)
        - target side AEN improvements (Chaitanya Kulkarni)
        - various fixes and minor improvements all over, icluding the
          nvme part of the lpfc driver"

   - Floppy code cleanup series (Willy, Denis)

   - Floppy contention fix (Jiri)

   - Loop CONFIGURE support (Martijn)

   - bcache fixes/improvements (Coly, Joe, Colin)

   - q->queuedata cleanups (Christoph)

   - Get rid of ioctl_by_bdev (Christoph, Stefan)

   - md/raid5 allocation fixes (Coly)

   - zero length array fixes (Gustavo)

   - swim3 task state fix (Xu)"

* tag 'for-5.8/drivers-2020-06-01' of git://git.kernel.dk/linux-block: (166 commits)
  bcache: configure the asynchronous registertion to be experimental
  bcache: asynchronous devices registration
  bcache: fix refcount underflow in bcache_device_free()
  bcache: Convert pr_<level> uses to a more typical style
  bcache: remove redundant variables i and n
  lpfc: Fix return value in __lpfc_nvme_ls_abort
  lpfc: fix axchg pointer reference after free and double frees
  lpfc: Fix pointer checks and comments in LS receive refactoring
  nvme: set dma alignment to qword
  nvmet: cleanups the loop in nvmet_async_events_process
  nvmet: fix memory leak when removing namespaces and controllers concurrently
  nvmet-rdma: add metadata/T10-PI support
  nvmet: add metadata support for block devices
  nvmet: add metadata/T10-PI support
  nvme: add Metadata Capabilities enumerations
  nvmet: rename nvmet_check_data_len to nvmet_check_transfer_len
  nvmet: rename nvmet_rw_len to nvmet_rw_data_len
  nvmet: add metadata characteristics for a namespace
  nvme-rdma: add metadata/T10-PI support
  nvme-rdma: introduce nvme_rdma_sgl structure
  ...
2020-06-02 15:37:03 -07:00
Linus Torvalds 750a02ab8d for-5.8/block-2020-06-01
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Merge tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Core block changes that have been queued up for this release:

   - Remove dead blk-throttle and blk-wbt code (Guoqing)

   - Include pid in blktrace note traces (Jan)

   - Don't spew I/O errors on wouldblock termination (me)

   - Zone append addition (Johannes, Keith, Damien)

   - IO accounting improvements (Konstantin, Christoph)

   - blk-mq hardware map update improvements (Ming)

   - Scheduler dispatch improvement (Salman)

   - Inline block encryption support (Satya)

   - Request map fixes and improvements (Weiping)

   - blk-iocost tweaks (Tejun)

   - Fix for timeout failing with error injection (Keith)

   - Queue re-run fixes (Douglas)

   - CPU hotplug improvements (Christoph)

   - Queue entry/exit improvements (Christoph)

   - Move DMA drain handling to the few drivers that use it (Christoph)

   - Partition handling cleanups (Christoph)"

* tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block: (127 commits)
  block: mark bio_wouldblock_error() bio with BIO_QUIET
  blk-wbt: rename __wbt_update_limits to wbt_update_limits
  blk-wbt: remove wbt_update_limits
  blk-throttle: remove tg_drain_bios
  blk-throttle: remove blk_throtl_drain
  null_blk: force complete for timeout request
  blk-mq: drain I/O when all CPUs in a hctx are offline
  blk-mq: add blk_mq_all_tag_iter
  blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx
  blk-mq: use BLK_MQ_NO_TAG in more places
  blk-mq: rename BLK_MQ_TAG_FAIL to BLK_MQ_NO_TAG
  blk-mq: move more request initialization to blk_mq_rq_ctx_init
  blk-mq: simplify the blk_mq_get_request calling convention
  blk-mq: remove the bio argument to ->prepare_request
  nvme: force complete cancelled requests
  blk-mq: blk-mq: provide forced completion method
  block: fix a warning when blkdev.h is included for !CONFIG_BLOCK builds
  block: blk-crypto-fallback: remove redundant initialization of variable err
  block: reduce part_stat_lock() scope
  block: use __this_cpu_add() instead of access by smp_processor_id()
  ...
2020-06-02 15:29:19 -07:00
Christoph Hellwig 88dca4ca5a mm: remove the pgprot argument to __vmalloc
The pgprot argument to __vmalloc is always PAGE_KERNEL now, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com> [hyperv]
Acked-by: Gao Xiang <xiang@kernel.org> [erofs]
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Wei Liu <wei.liu@kernel.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-22-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:11 -07:00
Guoqing Jiang db2c1d86cc md: remove __clear_page_buffers and use attach/detach_page_private
After introduction attach/detach_page_private in pagemap.h, we can remove
the duplicated code and call the new functions.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Song Liu <song@kernel.org>
Link: http://lkml.kernel.org/r/20200517214718.468-3-guoqing.jiang@cloud.ionos.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:07 -07:00
Ming Lei bf0beec060 blk-mq: drain I/O when all CPUs in a hctx are offline
Most of blk-mq drivers depend on managed IRQ's auto-affinity to setup
up queue mapping. Thomas mentioned the following point[1]:

"That was the constraint of managed interrupts from the very beginning:

 The driver/subsystem has to quiesce the interrupt line and the associated
 queue _before_ it gets shutdown in CPU unplug and not fiddle with it
 until it's restarted by the core when the CPU is plugged in again."

However, current blk-mq implementation doesn't quiesce hw queue before
the last CPU in the hctx is shutdown.  Even worse, CPUHP_BLK_MQ_DEAD is a
cpuhp state handled after the CPU is down, so there isn't any chance to
quiesce the hctx before shutting down the CPU.

Add new CPUHP_AP_BLK_MQ_ONLINE state to stop allocating from blk-mq hctxs
where the last CPU goes away, and wait for completion of in-flight
requests.  This guarantees that there is no inflight I/O before shutting
down the managed IRQ.

Add a BLK_MQ_F_STACKING and set it for dm-rq and loop, so we don't need
to wait for completion of in-flight requests from these drivers to avoid
a potential dead-lock. It is safe to do this for stacking drivers as those
do not use interrupts at all and their I/O completions are triggered by
underlying devices I/O completion.

[1] https://lore.kernel.org/linux-block/alpine.DEB.2.21.1904051331270.1802@nanos.tec.linutronix.de/

[hch: different retry mechanism, merged two patches, minor cleanups]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-29 10:23:25 -06:00
Christoph Hellwig 86240d5b68 dm: use bio_{start,end}_io_acct
Switch dm to use the nicer bio accounting helpers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:21:23 -06:00
Christoph Hellwig 85750aeb74 bcache: use bio_{start,end}_io_acct
Switch bcache to use the nicer bio accounting helpers, and call the
routines where we also sample the start time to give coherent accounting
results.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:21:23 -06:00
Coly Li 0c8d3fcead bcache: configure the asynchronous registertion to be experimental
In order to avoid the experimental async registration interface to
be treated as new kernel ABI for common users, this patch makes it
as an experimental kernel configure BCACHE_ASYNC_REGISTRAION.

This interface is for extreme large cached data situation, to make sure
the bcache device can always created without the udev timeout issue. For
normal users the async or sync registration does not make difference.

In future when we decide to use the asynchronous registration as default
behavior, this experimental interface may be removed.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:19:36 -06:00
Coly Li 9e23ccf8f0 bcache: asynchronous devices registration
When there is a lot of data cached on cache device, the bcach internal
btree can take a very long to validate during the backing device and
cache device registration. In my test, it may takes 55+ minutes to check
all the internal btree nodes.

The problem is that the registration is invoked by udev rules and the
udevd has 180 seconds timeout by default. If the btree node checking
time is longer than udevd timeout, the registering  process will be
killed by udevd with SIGKILL. If the registering process has pending
sigal, creating kthread for bcache will fail and the device registration
will fail. The result is, for bcache device which cached a lot of data
on cache device, the bcache device node like /dev/bcache<N> won't create
always due to the very long btree checking time.

A solution to avoid the udevd 180 seconds timeout is to register devices
in an asynchronous way. Which is, after writing cache or backing device
path into /sys/fs/bcache/register_async, the kernel code will create a
kworker and move all the btree node checking (for cache device) or dirty
data counting (for cached device) in the kwork context. Then the kworder
is scheduled on system_wq and the registration code just returned to
user space udev rule task. By this asynchronous way, the udev task for
bcache rule will complete in seconds, no matter how long time spent in
the kworker context, it won't be killed by udevd for a timeout.

After all the checking and counting are done asynchronously in the
kworker, the bcache device will eventually be created successfully.

This patch does the above chagne and add a register sysfs file
/sys/fs/bcache/register_async. Writing the registering device path into
this sysfs file will do the asynchronous registration.

The register_async interface is for very rare condition and won't be
used for common users. In future I plan to make the asynchronous
registration as default behavior, which depends on feedback for this
patch.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:19:36 -06:00
Coly Li 86da9f7367 bcache: fix refcount underflow in bcache_device_free()
The problematic code piece in bcache_device_free() is,

 785 static void bcache_device_free(struct bcache_device *d)
 786 {
 787     struct gendisk *disk = d->disk;
 [snipped]
 799     if (disk) {
 800             if (disk->flags & GENHD_FL_UP)
 801                     del_gendisk(disk);
 802
 803             if (disk->queue)
 804                     blk_cleanup_queue(disk->queue);
 805
 806             ida_simple_remove(&bcache_device_idx,
 807                               first_minor_to_idx(disk->first_minor));
 808             put_disk(disk);
 809         }
 [snipped]
 816 }

At line 808, put_disk(disk) may encounter kobject refcount of 'disk'
being underflow.

Here is how to reproduce the issue,
- Attche the backing device to a cache device and do random write to
  make the cache being dirty.
- Stop the bcache device while the cache device has dirty data of the
  backing device.
- Only register the backing device back, NOT register cache device.
- The bcache device node /dev/bcache0 won't show up, because backing
  device waits for the cache device shows up for the missing dirty
  data.
- Now echo 1 into /sys/fs/bcache/pendings_cleanup, to stop the pending
  backing device.
- After the pending backing device stopped, use 'dmesg' to check kernel
  message, a use-after-free warning from KASA reported the refcount of
  kobject linked to the 'disk' is underflow.

The dropping refcount at line 808 in the above code piece is added by
add_disk(d->disk) in bch_cached_dev_run(). But in the above condition
the cache device is not registered, bch_cached_dev_run() has no chance
to be called and the refcount is not added. The put_disk() for a non-
added refcount of gendisk kobject triggers a underflow warning.

This patch checks whether GENHD_FL_UP is set in disk->flags, if it is
not set then the bcache device was not added, don't call put_disk()
and the the underflow issue can be avoided.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:19:36 -06:00
Joe Perches 46f5aa8806 bcache: Convert pr_<level> uses to a more typical style
Remove the trailing newline from the define of pr_fmt and add newlines
to the uses.

Miscellanea:

o Convert bch_bkey_dump from multiple uses of pr_err to pr_cont
  as the earlier conversion was inappropriate done causing multiple
  lines to be emitted where only a single output line was desired
o Use vsprintf extension %pV in bch_cache_set_error to avoid multiple
  line output where only a single line output was desired
o Coalesce formats

Fixes: 6ae63e3501 ("bcache: replace printk() by pr_*() routines")

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:19:36 -06:00
Colin Ian King 3b5b7b1f70 bcache: remove redundant variables i and n
Variables i and n are being assigned but are never used. They are
redundant and can be removed.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Coly Li <colyli@suse.de>
Addresses-Coverity: ("Unused value")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-27 05:19:36 -06:00