1249727 Commits

Author SHA1 Message Date
Yu Kuai
0091c5a269 md/raid1: factor out helpers to choose the best rdev from read_balance()
The way that best rdev is chosen:

1) If the read is sequential from one rdev:
 - if rdev is rotational, use this rdev;
 - if rdev is non-rotational, use this rdev until total read length
   exceed disk opt io size;

2) If the read is not sequential:
 - if there is idle disk, use it, otherwise:
 - if the array has non-rotational disk, choose the rdev with minimal
   inflight IO;
 - if all the underlaying disks are rotational disk, choose the rdev
   with closest IO;

There are no functional changes, just to make code cleaner and prepare
for following refactor.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-12-yukuai1@huaweicloud.com
2024-02-29 22:49:46 -08:00
Yu Kuai
ba58f57fdf md/raid1: factor out the code to manage sequential IO
There is no functional change for now, make read_balance() cleaner and
prepare to fix problems and refactor the handler of sequential IO.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-11-yukuai1@huaweicloud.com
2024-02-29 22:49:46 -08:00
Yu Kuai
9f3ced7922 md/raid1: factor out choose_bb_rdev() from read_balance()
read_balance() is hard to understand because there are too many status
and branches, and it's overlong.

This patch factor out the case to read the rdev with bad blocks from
read_balance(), there are no functional changes.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-10-yukuai1@huaweicloud.com
2024-02-29 22:49:46 -08:00
Yu Kuai
dfa8ecd167 md/raid1: factor out choose_slow_rdev() from read_balance()
read_balance() is hard to understand because there are too many status
and branches, and it's overlong.

This patch factor out the case to read the slow rdev from
read_balance(), there are no functional changes.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-9-yukuai1@huaweicloud.com
2024-02-29 22:49:46 -08:00
Yu Kuai
31a7333175 md/raid1: factor out read_first_rdev() from read_balance()
read_balance() is hard to understand because there are too many status
and branches, and it's overlong.

This patch factor out the case to read the first rdev from
read_balance(), there are no functional changes.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-8-yukuai1@huaweicloud.com
2024-02-29 22:49:46 -08:00
Yu Kuai
f109207629 md/raid1-10: factor out a new helper raid1_should_read_first()
If resync is in progress, read_balance() should find the first usable
disk, otherwise, data could be inconsistent after resync is done. raid1
and raid10 implement the same checking, hence factor out the checking
to make code cleaner.

Noted that raid1 is using 'mddev->recovery_cp', which is updated after
all resync IO is done, while raid10 is using 'conf->next_resync', which
is inaccurate because raid10 update it before submitting resync IO.
Fortunately, raid10 read IO can't concurrent with resync IO, hence there
is no problem. And this patch also switch raid10 to use
'mddev->recovery_cp'.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-7-yukuai1@huaweicloud.com
2024-02-29 22:49:46 -08:00
Yu Kuai
f29841ff3b md/raid1-10: add a helper raid1_check_read_range()
The checking and handler of bad blocks appear many timers during
read_balance() in raid1 and raid10. This helper will be used in later
patches to simplify read_balance() a lot.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-6-yukuai1@huaweicloud.com
2024-02-29 22:49:46 -08:00
Yu Kuai
257ac239ff md/raid1: fix choose next idle in read_balance()
Commit 12cee5a8a29e ("md/raid1: prevent merging too large request") add
the case choose next idle in read_balance():

read_balance:
 for_each_rdev
  if(next_seq_sect == this_sector || dist == 0)
  -> sequential reads
   best_disk = disk;
   if (...)
    choose_next_idle = 1
    continue;

 for_each_rdev
 -> iterate next rdev
  if (pending == 0)
   best_disk = disk;
   -> choose the next idle disk
   break;

  if (choose_next_idle)
   -> keep using this rdev if there are no other idle disk
   contine

However, commit 2e52d449bcec ("md/raid1: add failfast handling for reads.")
remove the code:

-               /* If device is idle, use it */
-               if (pending == 0) {
-                       best_disk = disk;
-                       break;
-               }

Hence choose next idle will never work now, fix this problem by
following:

1) don't set best_disk in this case, read_balance() will choose the best
   disk after iterating all the disks;
2) add 'pending' so that other idle disk will be chosen;
3) add a new local variable 'sequential_disk' to record the disk, and if
   there is no other idle disk, 'sequential_disk' will be chosen;

Fixes: 2e52d449bcec ("md/raid1: add failfast handling for reads.")
Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-5-yukuai1@huaweicloud.com
2024-02-29 22:49:45 -08:00
Yu Kuai
2c27d09d3a md/raid1: record nonrot rdevs while adding/removing rdevs to conf
For raid1, each read will iterate all the rdevs from conf and check if
any rdev is non-rotational, then choose rdev with minimal IO inflight
if so, or rdev with closest distance otherwise.

Disk nonrot info can be changed through sysfs entry:

/sys/block/[disk_name]/queue/rotational

However, consider that this should only be used for testing, and user
really shouldn't do this in real life. Record the number of non-rotational
disks in conf, to avoid checking each rdev in IO fast path and simplify
read_balance() a little bit.

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-4-yukuai1@huaweicloud.com
2024-02-29 22:49:45 -08:00
Yu Kuai
969d6589ab md/raid1: factor out helpers to add rdev to conf
There are no functional changes, just make code cleaner and prepare to
record disk non-rotational information while adding and removing rdev to
conf

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-3-yukuai1@huaweicloud.com
2024-02-29 22:49:45 -08:00
Yu Kuai
3a0f007b69 md: add a new helper rdev_has_badblock()
The current api is_badblock() must pass in 'first_bad' and
'bad_sectors', however, many caller just want to know if there are
badblocks or not, and these caller must define two local variable that
will never be used.

Add a new helper rdev_has_badblock() that will only return if there are
badblocks or not, remove unnecessary local variables and replace
is_badblock() with the new helper in many places.

There are no functional changes, and the new helper will also be used
later to refactor read_balance().

Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-2-yukuai1@huaweicloud.com
2024-02-29 22:49:45 -08:00
Gui-Dong Han
dfd2bf4367 md/raid5: fix atomicity violation in raid5_cache_count
In raid5_cache_count():
    if (conf->max_nr_stripes < conf->min_nr_stripes)
        return 0;
    return conf->max_nr_stripes - conf->min_nr_stripes;
The current check is ineffective, as the values could change immediately
after being checked.

In raid5_set_cache_size():
    ...
    conf->min_nr_stripes = size;
    ...
    while (size > conf->max_nr_stripes)
        conf->min_nr_stripes = conf->max_nr_stripes;
    ...

Due to intermediate value updates in raid5_set_cache_size(), concurrent
execution of raid5_cache_count() and raid5_set_cache_size() may lead to
inconsistent reads of conf->max_nr_stripes and conf->min_nr_stripes.
The current checks are ineffective as values could change immediately
after being checked, raising the risk of conf->min_nr_stripes exceeding
conf->max_nr_stripes and potentially causing an integer overflow.

This possible bug is found by an experimental static analysis tool
developed by our team. This tool analyzes the locking APIs to extract
function pairs that can be concurrently executed, and then analyzes the
instructions in the paired functions to identify possible concurrency bugs
including data races and atomicity violations. The above possible bug is
reported when our tool analyzes the source code of Linux 6.2.

To resolve this issue, it is suggested to introduce local variables
'min_stripes' and 'max_stripes' in raid5_cache_count() to ensure the
values remain stable throughout the check. Adding locks in
raid5_cache_count() fails to resolve atomicity violations, as
raid5_set_cache_size() may hold intermediate values of
conf->min_nr_stripes while unlocked. With this patch applied, our tool no
longer reports the bug, with the kernel configuration allyesconfig for
x86_64. Due to the lack of associated hardware, we cannot test the patch
in runtime testing, and just verify it according to the code logic.

Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.")
Cc: stable@vger.kernel.org
Signed-off-by: Gui-Dong Han <2045gemini@gmail.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240112071017.16313-1-2045gemini@gmail.com
Signed-off-by: Song Liu <song@kernel.org>
2024-02-27 14:25:34 -08:00
Heming Zhao
ecbd8ebb51 md/md-bitmap: fix incorrect usage for sb_index
Commit d7038f951828 ("md-bitmap: don't use ->index for pages backing the
bitmap file") removed page->index from bitmap code, but left wrong code
logic for clustered-md. current code never set slot offset for cluster
nodes, will sometimes cause crash in clustered env.

Call trace (partly):
 md_bitmap_file_set_bit+0x110/0x1d8 [md_mod]
 md_bitmap_startwrite+0x13c/0x240 [md_mod]
 raid1_make_request+0x6b0/0x1c08 [raid1]
 md_handle_request+0x1dc/0x368 [md_mod]
 md_submit_bio+0x80/0xf8 [md_mod]
 __submit_bio+0x178/0x300
 submit_bio_noacct_nocheck+0x11c/0x338
 submit_bio_noacct+0x134/0x614
 submit_bio+0x28/0xdc
 submit_bh_wbc+0x130/0x1cc
 submit_bh+0x1c/0x28

Fixes: d7038f951828 ("md-bitmap: don't use ->index for pages backing the bitmap file")
Cc: stable@vger.kernel.org # v6.6+
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240223121128.28985-1-heming.zhao@suse.com
2024-02-26 13:34:44 -08:00
Li Nan
e9b0a1556c md: check mddev->pers before calling md_set_readonly()
If 'mddev->pers' is NULL, there is nothing to do in md_set_readonly().
Except for md_ioctl(), the other two callers of md_set_readonly() have
already checked 'mddev->pers'. To simplify the code, move the check of
'mddev->pers' to the caller.

Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-10-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
650b2e69ff md: clean up openers check in do_md_stop() and md_set_readonly()
Before stopping or setting readonly, mddev_set_closing_and_sync_blockdev()
is always called to check the openers. So no longer need to check it again
in do_md_stop() and md_set_readonly(). Clean it up.

Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-9-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
99b902ac17 md: sync blockdev before stopping raid or setting readonly
Commit a05b7ea03d72 ("md: avoid crash when stopping md array races
with closing other open fds.") added sync_block before stopping raid and
setting readonly. Later in commit 260fa034ef7a ("md: avoid deadlock when
dirty buffers during md_stop.") it is moved to ioctl. array_state_store()
was ignored. Add sync blockdev to array_state_store() now.

Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-8-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
f74aaf614e md: factor out a helper to sync mddev
There are no functional changes, prepare to sync mddev in
array_state_store().

Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-7-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
9674f54e41 md: Don't clear MD_CLOSING when the raid is about to stop
The raid should not be opened anymore when it is about to be stopped.
However, other processes can open it again if the flag MD_CLOSING is
cleared before exiting. From now on, this flag will not be cleared when
the raid will be stopped.

Fixes: 065e519e71b2 ("md: MD_CLOSING needs to be cleared after called md_set_readonly or do_md_stop")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-6-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
91b26a39fb md: return directly before setting did_set_md_closing
There is nothing to do at 'out' before setting 'did_set_md_closing'
in md_ioctl(). Return directly, and it will help us to remove
'did_set_md_closing' later.

Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-5-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
9dd8702e7c md: clean up invalid BUG_ON in md_ioctl
'disk->private_data' is set to mddev in md_alloc() and never set to NULL,
and users need to open mddev before submitting ioctl. So mddev must not
have been freed during ioctl, and there is no need to check mddev here.
Clean up it.

Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-4-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
4e26593944 md: changed the switch of RAID_VERSION to if
There is only one case of this 'switch'. Change it to 'if'.

Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-3-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Li Nan
2fe4ffc3ec md: merge the check of capabilities into md_ioctl_valid()
There is no functional change. Just to make code cleaner.

Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240226031444.3606764-2-linan666@huaweicloud.com
2024-02-26 10:22:22 -08:00
Chengming Zhou
82c6515d8a bdev: remove SLAB_MEM_SPREAD flag usage
The SLAB_MEM_SPREAD flag is already a no-op as of 6.8-rc1, remove
its usage so we can delete it from slab. No functional change.

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Link: https://lore.kernel.org/r/20240224134646.829105-1-chengming.zhou@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-24 13:16:08 -07:00
Qais Yousef
af550e4c96 block/blk-mq: Don't complete locally if capacities are different
The logic in blk_mq_complete_need_ipi() assumes SMP systems where all
CPUs have equal compute capacities and only LLC cache can make
a different on perceived performance. But this assumption falls apart on
HMP systems where LLC is shared, but the CPUs have different capacities.
Staying local then can have a big performance impact if the IO request
was done from a CPU with higher capacity but the interrupt is serviced
on a lower capacity CPU.

Use the new cpus_equal_capacity() function to check if we need to send
an IPI.

Without the patch I see the BLOCK softirq always running on little cores
(where the hardirq is serviced). With it I can see it running on all
cores.

This was noticed after the topology change [1] where now on a big.LITTLE
we truly get that the LLC is shared between all cores where as in the
past it was being misrepresented for historical reasons. The logic
exposed a missing dependency on capacities for such systems where there
can be a big performance difference between the CPUs.

This of course introduced a noticeable change in behavior depending on
how the topology is presented. Leading to regressions in some workloads
as the performance of the BLOCK softirq on littles can be noticeably
worse on some platforms.

Worth noting that we could have checked for capacities being greater
than or equal instead for equality. This will lead to favouring higher
performance always. But opted for equality instead to match the
performance of the requester without making an assumption that can lead
to power trade-offs which these systems tend to be sensitive about. If
the requester would like to run faster, it's better to rely on the
scheduler to give the IO requester via some facility to run on a faster
core; and then if the interrupt triggered on a CPU with different
capacity we'll make sure to match the performance the requester is
supposed to run at.

[1] https://lpc.events/event/16/contributions/1342/attachments/962/1883/LPC-2022-Android-MC-Phantom-Domains.pdf

Signed-off-by: Qais Yousef <qyousef@layalina.io>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240223155749.2958009-3-qyousef@layalina.io
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-24 12:48:01 -07:00
Qais Yousef
b361c9027b sched: Add a new function to compare if two cpus have the same capacity
The new helper function is needed to help blk-mq check if it needs to
dispatch the softirq on another CPU to match the performance level the
IO requester is running at. This is important on HMP systems where not
all CPUs have the same compute capacity.

Signed-off-by: Qais Yousef <qyousef@layalina.io>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240223155749.2958009-2-qyousef@layalina.io
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-24 12:48:01 -07:00
Keith Busch
8a08c5fd89 blk-lib: check for kill signal
Some of these block operations can access a significant capacity and
take longer than the user expected. A user may change their mind about
wanting to run that command and attempt to kill the process and do
something else with their device. But since the task is uninterruptable,
they have to wait for it to finish, which could be many hours.

Check for a fatal signal at each iteration so the user doesn't have to
wait for their regretted operation to complete naturally.

Reported-by: Conrad Meyer <conradmeyer@meta.com>
Tested-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240223155910.3622666-5-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-24 12:46:46 -07:00
Keith Busch
0eb4db4706 block: io wait hang check helper
This is the same in two places, and another will be added soon. Create a
helper for it.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240223155910.3622666-4-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-24 12:46:46 -07:00
Keith Busch
76a27e1b53 block: cleanup __blkdev_issue_write_zeroes
Use min to calculate the next number of sectors like everyone else.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240223155910.3622666-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-24 12:46:46 -07:00
Keith Busch
5affe497c3 block: blkdev_issue_secure_erase loop style
Use consistent coding style in this file. All the other loops for the
same purpose use "while (nr_sects)", so they win.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240223155910.3622666-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-24 12:46:46 -07:00
Li Nan
03f12122b2 block: fix deadlock between bd_link_disk_holder and partition scan
'open_mutex' of gendisk is used to protect open/close block devices. But
in bd_link_disk_holder(), it is used to protect the creation of symlink
between holding disk and slave bdev, which introduces some issues.

When bd_link_disk_holder() is called, the driver is usually in the process
of initialization/modification and may suspend submitting io. At this
time, any io hold 'open_mutex', such as scanning partitions, can cause
deadlocks. For example, in raid:

T1                              T2
bdev_open_by_dev
 lock open_mutex [1]
 ...
  efi_partition
  ...
   md_submit_bio
				md_ioctl mddev_syspend
				  -> suspend all io
				 md_add_new_disk
				  bind_rdev_to_array
				   bd_link_disk_holder
				    try lock open_mutex [2]
    md_handle_request
     -> wait mddev_resume

T1 scan partition, T2 add a new device to raid. T1 waits for T2 to resume
mddev, but T2 waits for open_mutex held by T1. Deadlock occurs.

Fix it by introducing a local mutex 'blk_holder_mutex' to replace
'open_mutex'.

Fixes: 1b0a2d950ee2 ("md: use new apis to suspend array for ioctls involed array reconfiguration")
Reported-by: mgperkow@gmail.com
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218459
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240221090122.1281868-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-23 07:44:19 -07:00
Damien Le Moal
522d73526f block: Do not include rbtree.h in blk-zoned.c
The block zone code does not use RB-tree. So remove the include of
linux/rbtree.h as it is not needed.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240222131724.1803520-2-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-22 10:35:18 -07:00
Damien Le Moal
c8f6f88d25 block: Clear zone limits for a non-zoned stacked queue
Device mapper may create a non-zoned mapped device out of a zoned device
(e.g., the dm-zoned target). In such case, some queue limit such as the
max_zone_append_sectors and zone_write_granularity endup being non zero
values for a block device that is not zoned. Avoid this by clearing
these limits in blk_stack_limits() when the stacked zoned limit is
false.

Fixes: 3093a479727b ("block: inherit the zoned characteristics in blk_stack_limits")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240222131724.1803520-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-22 10:35:18 -07:00
John Garry
0f225f8787 null_blk: Delete nullb.{queue_depth, nr_queues}
Since commit 8b631f9cf0b8 ("null_blk: remove the bio based I/O path"),
struct nullb members queue_depth and nr_queues are only ever written, so
delete them.

With that, null_exit_hctx() can also be deleted.

Signed-off-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20240222083420.6026-1-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-22 10:08:47 -07:00
Christoph Hellwig
4068550870 pktcdvd: set queue limits at disk allocation time
Remove pkt_init_queue and just pass the two parameters directly to
blk_alloc_disk.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240222073647.3776769-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-22 10:08:20 -07:00
Christoph Hellwig
6f420d6a2d pktcdvd: stop setting q->queuedata
The two users can get the private data from the gendisk with one less
pointer dereference, and we can drop the useless q parameter from
pkt_make_request_write.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240222073647.3776769-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-22 10:08:20 -07:00
Christoph Hellwig
a3911966bd block: fix virt_boundary handling in blk_validate_limits
Don't set the default max_segment_size value when a virt_boundary is
used.

Fixes: d690cb8ae14b ("block: add an API to atomically update queue limits")
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20240221125010.3609444-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-21 07:21:28 -07:00
Christoph Hellwig
e440626b1c null_blk: pass queue_limits to blk_mq_alloc_disk
Pass the queue limits directly to blk_mq_alloc_disk instead of
setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-20 06:21:27 -07:00
Christoph Hellwig
0a39e550c1 null_blk: remove null_gendisk_register
null_gendisk_register isn't a very useful abstraction given that it
doesn't even allocate the gendisk.  Merge it into the only caller
instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-20 06:21:27 -07:00
Christoph Hellwig
72ca28765f null_blk: refactor tag_set setup
Move the tagset initialization out of null_add_dev into a new
null_setup_tagset helper, and move the shared vs local differences
out of null_init_tag_set into the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-20 06:21:27 -07:00
Christoph Hellwig
e32b085536 null_blk: initialize the tag_set timeout in null_init_tag_set
Otherwise it will be reset to the always same value when initializing a
device using the shared tag_set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-20 06:21:27 -07:00
Christoph Hellwig
8b631f9cf0 null_blk: remove the bio based I/O path
The bio based I/O path complicates null_blk and also make various
data structures, including the per-command one way bigger than
required for the main request based interface.   As the bio-based
path is mostly used by stacking drivers and simple memory based
drivers, and brd is a good example driver for the latter there is
no need to have a bio based path in null_blk.  Remove the path
to simplify the driver and make future block layer API changes
simpler by not having to deal with the complex two API setup in
null_blk.

Note that the queue_mode field in struct nullb_device is kept as
that is simpler than having two different places to check the
value and fully open coding the debugfs helpers as the existing
ones won't work without a named struct member.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-20 06:21:27 -07:00
Christoph Hellwig
616f876617 mmc: pass queue_limits to blk_mq_alloc_disk
Pass the queue limit set at initialization time directly to
blk_mq_alloc_disk instead of updating it right after the allocation.

This requires refactoring the code a bit so that what was mmc_setup_queue
before also allocates the gendisk now and actually sets all limits.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20240215070300.2200308-18-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 17:00:29 -07:00
Christoph Hellwig
494ea040bc ublk: pass queue_limits to blk_mq_alloc_disk
Pass the limits ublk imposes directly to blk_mq_alloc_disk instead of
setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240215070300.2200308-17-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:32 -07:00
Christoph Hellwig
066be10aef scm_blk: pass queue_limits to blk_mq_alloc_disk
Pass the few limits scm_block imposes directly to blk_mq_alloc_disk
instead of setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240215070300.2200308-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:32 -07:00
Christoph Hellwig
21b700c081 ubiblock: pass queue_limits to blk_mq_alloc_disk
Pass the few limits ubiblock imposes directly to blk_mq_alloc_disk
instead of setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Link: https://lore.kernel.org/r/20240215070300.2200308-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:32 -07:00
Christoph Hellwig
3ec44e52bf mtd_blkdevs: pass queue_limits to blk_mq_alloc_disk
Pass the few limits mtd_blkdevs imposes directly to blk_mq_alloc_disk
instead of setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240215070300.2200308-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:32 -07:00
Christoph Hellwig
9f633ecd43 mspro_block: pass queue_limits to blk_mq_alloc_disk
Pass the few limits mspro_block imposes directly to blk_mq_alloc_disk
instead of setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240215070300.2200308-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:31 -07:00
Christoph Hellwig
f93b43ae3f ms_block: pass queue_limits to blk_mq_alloc_disk
Pass the few limits ms_block imposes directly to blk_mq_alloc_disk
instead of setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240215070300.2200308-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:31 -07:00
Christoph Hellwig
a339cf2bbf gdrom: pass queue_limits to blk_mq_alloc_disk
Pass the few limits gdrom imposes directly to blk_mq_alloc_disk instead
of setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240215070300.2200308-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:31 -07:00
Christoph Hellwig
d0fa9a8b0a sunvdc: pass queue_limits to blk_mq_alloc_disk
Pass the few limits sunvdc imposes directly to blk_mq_alloc_disk instead
of setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240215070300.2200308-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-19 16:59:31 -07:00