The member is not needed since we can call get_disk_ro to achieve the
same goal.
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-4-guoqing.jiang@linux.devSigned-off-by: Jens Axboe <axboe@kernel.dk>

For map scenario, rsp is freed in two places:

1. msg_open_conf frees rsp if rtrs_clt_request returns 0.

2. Otherwise, rsp is freed by the call sites of rtrs_clt_request.

Now, We'd like to control full lifecycle of rsp in rnbd_clt_map_device,
with that, it is feasible to pass rsp to rnbd_client_setup_device in
next commit.

For 1, it is possible to free rsp from the caller of send_usr_msg
because of the synchronization of iu->comp.wait. And we put iu later
in rnbd_clt_map_device to ensure order of release rsp and iu.
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-3-guoqing.jiang@linux.devSigned-off-by: Jens Axboe <axboe@kernel.dk>

Let's open code it in rnbd_clt_map_device, then we can use information
from rsp to setup gendisk and request_queue in next commits. After that,
we can remove some members (wc, fua and max_hw_sectors etc) from struct
rnbd_clt_dev.
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-2-guoqing.jiang@linux.devSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use bitmap_zalloc()/bitmap_free() instead of hand-writing them.

It is less verbose and it improves the semantic.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/7c4d3116ba843fc4a8ae557dd6176352a6cd0985.1656864320.git.christophe.jaillet@wanadoo.frSigned-off-by: Jens Axboe <axboe@kernel.dk>

There are 2 spelling mistakes in comments. Fix it.
Signed-off-by: Zhang Jiaming <jiaming@nfschina.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The block layer defaults the maximum segments to 128, which means
requests tend to get split around the 512KB depending on how many
pages can be merged. There's no such restriction in the raid5 code
so increase the limit to USHRT_MAX so that larger requests can be
sent as one.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Add a debug print for raid5_make_request() so that each request is
printed and add the logical sector number to the debug print in
__add_stripe_bio().
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

raid5_make_request() loops through every page in the request,
finds the appropriate stripe and adds the bio for that page in the
disk.

This causes a great deal of contention on the hash_lock and extra
work seeing each stripe must be found once for every data disk.

The number of times a stripe must be found can be reduced by pivoting
raid5_make_request() so that it loops through every stripe and then
loops through every disk in that stripe to see if the bio must be
added. This reduces the number of times the hash lock must be taken
by a factor equal to the number of data disks.

To accomplish this, the logical sectors that have already been added
must be tracked. Tracking them is done with a bitmap: the bits
for all pages are set at the start of the request and each bit
is cleared once the bio is added to a stripe.

Finding the next sector to be done is then just a call to
find_first_bit() so that sectors that have been done can simply be
skipped.

One minor downside is that the maximum sectors for a request must be
limited so that the bitmap can be appropriately sized on the stack.
This limit is arbitrarily chosen to be 256 stripe pages which works out
to 1MB if PAGE_SIZE == DEFAULT_STRIPE_SIZE. This doesn't actually
restrict the maximum request further seeing the default block queue
settings are used which restricts the number of segments to 128 (which
results in request sizes that are approximately 512KB).
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When testing if a previous stripe has had reshape expand past it, use
the earliest or latest logical sector in all the disks for that stripe
head. This will allow adding multiple disks at a time in a subesquent
patch.

To do this cleaner, refactor the check into a helper function called
stripe_ahead_of_reshape().
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Factor out two helper functions from add_stripe_bio(): one to check for
overlap (stripe_bio_overlaps()), and one to actually add the bio to the
stripe (__add_stripe_bio()). The latter function will always succeed.

This will be useful in the next patch so that overlap can be checked for
multiple disks before adding any
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When batching, every stripe head has to find the previous stripe head to
add to the batch list. This involves taking the hash lock which is
highly contended during IO.

Instead of finding the previous stripe_head each time, store a
reference to the previous stripe_head in a pointer so that it doesn't
require taking the contended lock another time.

The reference to the previous stripe must be released before scheduling
and waiting for work to get done. Otherwise, it can hold up
raid5_activate_delayed() and deadlock.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The for loop with retry label can be more cleanly expressed as a while
loop by moving the logical_sector increment into the success path.

No functional changes intended.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Now that prepare_to_wait() isn't in the way, move read_sequcount_begin()
into make_stripe_request().

No functional changes intended.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

prepare_to_wait() can be reasonably called after schedule instead of
setting a flag and preparing in the next loop iteration.

This means that prepare_to_wait() will be called before
read_seqcount_begin(), but there shouldn't be any reason that the order
matters here. On the first iteration of the loop prepare_to_wait() is
already called first.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Factor out the inner loop of raid5_make_request() into it's own helper
called make_stripe_request().

The helper returns a number of statuses: SUCCESS, RETRY,
SCHEDULE_AND_RETRY and FAIL. This makes the code a bit easier to
understand and allows the SCHEDULE_AND_RETRY path to be made common.

A context structure is added to contain do_flush. It will be used
more in subsequent patches for state that needs to be kept
outside the loop.

No functional changes intended. This will be cleaned up further in
subsequent patches to untangle the gen_lock and do_prepare logic
further.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Both uses of find_stripe() require a fairly complicated dance to
increment the reference count. Move this into a common find_get_stripe()
helper.

No functional changes intended.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

stripe_add_to_batch_list() is better done in the loop in make_request
instead of inside add_stripe_bio(). This is clearer and allows for
storing the batch_head state outside the loop in a subsequent patch.

The call to add_stripe_bio() in retry_aligned_read() is for read
and batching only applies to write. So it's impossible for batching
to happen at that call site.

No functional changes intended.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Break immediately if raid5_get_active_stripe() returns NULL and deindent
the rest of the loop. Annotate this check with an unlikely().

This makes the code easier to read and reduces the indentation level.

No functional changes intended.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

There are a few uses of an ugly ternary operator in raid5_make_request()
to check if a sector is a head of a reshape sector.

Factor this out into a simple helper called ahead_of_reshape().

No functional changes intended.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The check in raid5_make_request differs very slightly from the logic
that causes it to block lower down. This likely does not cause a bug
as the check is fuzzy anyway (as reshape may move on between the first
check and the subsequent check). However, make it consistent so it can
be cleaned up in a subsequent patch.

The condition which causes the schedule is:

 !(mddev->reshape_backwards ? logical_sector < conf->reshape_progress :
   logical_sector >= conf->reshape_progress) &&
  (mddev->reshape_backwards ? logical_sector < conf->reshape_safe :
   logical_sector >= conf->reshape_safe)

The condition that causes the early bailout is made to match this.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Since the bug which commit 8b48ec23 ("md: don't unregister sync_thread
with reconfig_mutex held") fixed is related with action_store path, other
callers which reap sync_thread didn't need to be changed.

Let's pull md_unregister_thread from md_reap_sync_thread, then fix previous
bug with belows.

1. unlock mddev before md_reap_sync_thread in action_store.
2. save reshape_position before unlock, then restore it to ensure position
   not changed accidentally by others.
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Boot-time assembly of arrays with md= command-line arguments breaks when
CONFIG_BLOCK_LEGACY_AUTOLOAD is unset. md_setup_drive() in md-autodetect.c
calls blkdev_get_by_dev(), assuming this implicitly creates the block
device.

Fix this by attempting to md_alloc() the array first. As in the probe path,
ignore any error as failure is caught by blkdev_get_by_dev() anyway.
Signed-off-by: Chris Webb <chris@arachsys.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The mdadm test 07layouts randomly produces a kernel hung task deadlock.
The deadlock is caused by the suspend_lo/suspend_hi files being set by
the mdadm background process during reshape and not being cleared
because the process hangs. (Leaving aside the issue of the fragility of
freezing kernel tasks by buggy userspace processes...)

When the background mdadm process hangs it, is waiting (without a
timeout) on a change to the sync_completed file signalling that the
reshape has completed. The process is woken up a couple times when
the reshape finishes but it is woken up before MD_RECOVERY_RUNNING
is cleared so sync_completed_show() reports 0 instead of "none".

To fix this, notify the sysfs file in md_reap_sync_thread() after
MD_RECOVERY_RUNNING has been cleared. This wakes up mdadm and causes
it to continue and write to suspend_lo/suspend_hi to allow IO to
continue.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The 07layouts test in mdadm fails on some systems. The failure
presents itself as the backup file not being removed before the next
layout is grown into:

  mdadm: /dev/md0: cannot create backup file /tmp/md-test-backup:
      File exists

This is because the background mdadm process, which is responsible for
cleaning up this backup file gets into an infinite loop waiting for
the reshape to start. mdadm checks the mdstat file if a reshape is
going and, if it is not, it waits for an event on the file or times
out in 5 seconds. On faster machines, the reshape may complete before
the 5 seconds times out, and thus the background mdadm process loops
waiting for a reshape to start that has already occurred.

mdadm reads the mdstat file to start, but mdstat does not report that the
reshape has begun, even though it has indeed begun. So the mdstat_wait()
call (in mdadm) which polls on the mdstat file won't ever return until
timing out.

The reason mdstat reports the reshape has started is due to an issue
in status_resync(). recovery_active is subtracted from curr_resync which
will result in a value of zero for the first chunk of reshaped data, and
the resulting read will report no reshape in progress.

To fix this, if "resync - recovery_active" is an overloaded value, force
the value to be MD_RESYNC_ACTIVE so the code reports a resync in progress.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Comments in the code document special values used for
mddev->curr_resync. Make this clearer by using an enum to label these
values.

The only functional change is a couple places use the wrong comparison
operator that implied 3 is another special value. They are all
fixed to imply that 3 or greater is an active resync.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

radix_tree_lookup_slot() and radix_tree_replace_slot() API expect the
slot returned and looked up to be marked with __rcu. Otherwise
sparse warnings are generated:

  drivers/md/raid5-cache.c:2939:23: warning: incorrect type in
			assignment (different address spaces)
  drivers/md/raid5-cache.c:2939:23:    expected void **pslot
  drivers/md/raid5-cache.c:2939:23:    got void [noderef] __rcu **
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

A NULL pointer dereferlence on conf->log is seen randomly with
the mdadm test 21raid5cache. Kasan reporst:

BUG: KASAN: null-ptr-deref in r5l_reclaimable_space+0xf5/0x140
Read of size 8 at addr 0000000000000860 by task md0_reclaim/3086

Call Trace:
  dump_stack_lvl+0x5a/0x74
  kasan_report.cold+0x5f/0x1a9
  __asan_load8+0x69/0x90
  r5l_reclaimable_space+0xf5/0x140
  r5l_do_reclaim+0xf4/0x5e0
  r5l_reclaim_thread+0x69/0x3b0
  md_thread+0x1a2/0x2c0
  kthread+0x177/0x1b0
  ret_from_fork+0x22/0x30

This is caused by conf->log being cleared in r5l_exit_log() before
stopping the reclaim thread.

To fix this, clear conf->log after the reclaim_thread is unregistered
and after flushing disable_writeback_work.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The only place that uses RCU to access conf->log is in
r5l_log_disk_error(). This function is mostly used in the IO path
and once with mddev_lock() held in raid5_change_consistency_policy().

It is known that the IO will be suspended before the log is freed and
r5l_log_exit() is called with the mddev_lock() held.

This should mean that conf->log can not be freed while the function is
being called, so the RCU protection is not necessary. Drop the
rcu_read_lock() as well as the synchronize_rcu() and
rcu_assign_pointer() usage.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The mddev->lock spinlock doesn't protect against the removal of
conf->log in r5l_exit_log() so conf->log may be freed before it
is used.

To fix this, take the mddev_lock() insteaad of the mddev->lock spinlock.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The raid5-cache code relies on there being no IO in flight when
log_exit() is called. There are two places where this is not
guaranteed so add mddev_suspend() and mddev_resume() calls to these
sites.

The site in raid5_change_consistency_policy() is in the error path,
and another similar call site already has suspend/resume calls just
below it; so it should be equally safe to make that change here.

There is one remaining site in raid5_remove_disk() that we call log_exit()
without suspending the array. Unfortunately, as the comment stated, we
cannot call mddev_suspend from raid5d.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ppl_handle_flush_request() takes an struct r5log argument but doesn't
use it. It has no buisiness taking this argument as it is only used
by raid5-cache and has no way to derference it anyway. Remove
the argument.

No functional changes intended.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

extern is not necessary and recommended against when defining prototype
functions in headers. checkpatch.pl complains about these. So remove
them.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Add link to patchwork:

   https://patchwork.kernel.org/project/linux-raid/list/Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We usually do all our bitmap IO in units of PAGE_SIZE.

With very small or oddly sized external meta data, or with
PAGE_SIZE != 4k, it can happen that our last on-disk bitmap page
is not fully PAGE_SIZE aligned, so we may need to adjust the size
of the IO.

We used to do that with
  min_t(unsigned int, PAGE_SIZE,
	last_allowed_sector - current_offset);
And for just the right diff, (unsigned int)(diff) will result in 0.

A bio of length 0 will correctly be rejected with an IO error
(and some scary WARN_ON_ONCE()) by the scsi layer.

Do the calculation properly.
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20220622204932.196830-1-christoph.boehmwalder@linbit.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Merge tag 'for-6.0/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Refactor DM core's mempool allocation so that it clearer by not being
   split acorss files.

 - Improve DM core's BLK_STS_DM_REQUEUE and BLK_STS_AGAIN handling.

 - Optimize DM core's more common bio splitting by eliminating the use
   of bio cloning with bio_split+bio_chain. Shift that cloning cost to
   the relatively unlikely dm_io requeue case that only occurs during
   error handling. Introduces dm_io_rewind() that will clone a bio that
   reflects the subset of the original bio that must be requeued.

 - Remove DM core's dm_table_get_num_targets() wrapper and audit all
   dm_table_get_target() callers.

 - Fix potential for OOM with DM writecache target by setting a default
   MAX_WRITEBACK_JOBS (set to 256MiB or 1/16 of total system memory,
   whichever is smaller).

 - Fix DM writecache target's stats that are reported through
   DM-specific table info.

 - Fix use-after-free crash in dm_sm_register_threshold_callback().

 - Refine DM core's Persistent Reservation handling in preparation for
   broader work Mike Christie is doing to add compatibility with
   Microsoft Windows Failover Cluster.

 - Fix various KASAN reported bugs in the DM raid target.

 - Fix DM raid target crash due to md_handle_request() bio splitting
   that recurses to block core without properly initializing the bio's
   bi_dev.

 - Fix some code comment typos and fix some Documentation formatting.

* tag 'for-6.0/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (29 commits)
  dm: fix dm-raid crash if md_handle_request() splits bio
  dm raid: fix address sanitizer warning in raid_resume
  dm raid: fix address sanitizer warning in raid_status
  dm: Start pr_preempt from the same starting path
  dm: Fix PR release handling for non All Registrants
  dm: Start pr_reserve from the same starting path
  dm: Allow dm_call_pr to be used for path searches
  dm: return early from dm_pr_call() if DM device is suspended
  dm thin: fix use-after-free crash in dm_sm_register_threshold_callback
  dm writecache: count number of blocks discarded, not number of discard bios
  dm writecache: count number of blocks written, not number of write bios
  dm writecache: count number of blocks read, not number of read bios
  dm writecache: return void from functions
  dm kcopyd: use __GFP_HIGHMEM when allocating pages
  dm writecache: set a default MAX_WRITEBACK_JOBS
  Documentation: dm writecache: Render status list as list
  Documentation: dm writecache: add blank line before optional parameters
  dm snapshot: fix typo in snapshot_map() comment
  dm raid: remove redundant "the" in parse_raid_params() comment
  dm cache: fix typo in 2 comment blocks
  ...

Pull block updates from Jens Axboe:

 - Improve the type checking of request flags (Bart)

 - Ensure queue mapping for a single queues always picks the right queue
   (Bart)

 - Sanitize the io priority handling (Jan)

 - rq-qos race fix (Jinke)

 - Reserved tags handling improvements (John)

 - Separate memory alignment from file/disk offset aligment for O_DIRECT
   (Keith)

 - Add new ublk driver, userspace block driver using io_uring for
   communication with the userspace backend (Ming)

 - Use try_cmpxchg() to cleanup the code in various spots (Uros)

 - Finally remove bdevname() (Christoph)

 - Clean up the zoned device handling (Christoph)

 - Clean up independent access range support (Christoph)

 - Clean up and improve block sysfs handling (Christoph)

 - Clean up and improve teardown of block devices.

   This turns the usual two step process into something that is simpler
   to implement and handle in block drivers (Christoph)

 - Clean up chunk size handling (Christoph)

 - Misc cleanups and fixes (Bart, Bo, Dan, GuoYong, Jason, Keith, Liu,
   Ming, Sebastian, Yang, Ying)

* tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block: (178 commits)
  ublk_drv: fix double shift bug
  ublk_drv: make sure that correct flags(features) returned to userspace
  ublk_drv: fix error handling of ublk_add_dev
  ublk_drv: fix lockdep warning
  block: remove __blk_get_queue
  block: call blk_mq_exit_queue from disk_release for never added disks
  blk-mq: fix error handling in __blk_mq_alloc_disk
  ublk: defer disk allocation
  ublk: rewrite ublk_ctrl_get_queue_affinity to not rely on hctx->cpumask
  ublk: fold __ublk_create_dev into ublk_ctrl_add_dev
  ublk: cleanup ublk_ctrl_uring_cmd
  ublk: simplify ublk_ch_open and ublk_ch_release
  ublk: remove the empty open and release block device operations
  ublk: remove UBLK_IO_F_PREFLUSH
  ublk: add a MAINTAINERS entry
  block: don't allow the same type rq_qos add more than once
  mmc: fix disk/queue leak in case of adding disk failure
  ublk_drv: fix an IS_ERR() vs NULL check
  ublk: remove UBLK_IO_F_INTEGRITY
  ublk_drv: remove unneeded semicolon
  ...

Pull io_uring zerocopy support from Jens Axboe:
 "This adds support for efficient support for zerocopy sends through
  io_uring. Both ipv4 and ipv6 is supported, as well as both TCP and
  UDP.

  The core network changes to support this is in a stable branch from
  Jakub that both io_uring and net-next has pulled in, and the io_uring
  changes are layered on top of that.

  All of the work has been done by Pavel"

* tag 'for-5.20/io_uring-zerocopy-send-2022-07-29' of git://git.kernel.dk/linux-block: (34 commits)
  io_uring: notification completion optimisation
  io_uring: export req alloc from core
  io_uring/net: use unsigned for flags
  io_uring/net: make page accounting more consistent
  io_uring/net: checks errors of zc mem accounting
  io_uring/net: improve io_get_notif_slot types
  selftests/io_uring: test zerocopy send
  io_uring: enable managed frags with register buffers
  io_uring: add zc notification flush requests
  io_uring: rename IORING_OP_FILES_UPDATE
  io_uring: flush notifiers after sendzc
  io_uring: sendzc with fixed buffers
  io_uring: allow to pass addr into sendzc
  io_uring: account locked pages for non-fixed zc
  io_uring: wire send zc request type
  io_uring: add notification slot registration
  io_uring: add rsrc referencing for notifiers
  io_uring: complete notifiers in tw
  io_uring: cache struct io_notif
  io_uring: add zc notification infrastructure
  ...

Pull io_uring buffered writes support from Jens Axboe:
 "This contains support for buffered writes, specifically for XFS. btrfs
  is in progress, will be coming in the next release.

  io_uring does support buffered writes on any file type, but since the
  buffered write path just always -EAGAIN (or -EOPNOTSUPP) any attempt
  to do so if IOCB_NOWAIT is set, any buffered write will effectively be
  handled by io-wq offload. This isn't very efficient, and we even have
  specific code in io-wq to serialize buffered writes to the same inode
  to avoid further inefficiencies with thread offload.

  This is particularly sad since most buffered writes don't block, they
  simply copy data to a page and dirty it. With this pull request, we
  can handle buffered writes a lot more effiently.

  If balance_dirty_pages() needs to block, we back off on writes as
  indicated.

  This improves buffered write support by 2-3x.

  Jan Kara helped with the mm bits for this, and Stefan handled the
  fs/iomap/xfs/io_uring parts of it"

* tag 'for-5.20/io_uring-buffered-writes-2022-07-29' of git://git.kernel.dk/linux-block:
  mm: honor FGP_NOWAIT for page cache page allocation
  xfs: Add async buffered write support
  xfs: Specify lockmode when calling xfs_ilock_for_iomap()
  io_uring: Add tracepoint for short writes
  io_uring: fix issue with io_write() not always undoing sb_start_write()
  io_uring: Add support for async buffered writes
  fs: Add async write file modification handling.
  fs: Split off inode_needs_update_time and __file_update_time
  fs: add __remove_file_privs() with flags parameter
  fs: add a FMODE_BUF_WASYNC flags for f_mode
  iomap: Return -EAGAIN from iomap_write_iter()
  iomap: Add async buffered write support
  iomap: Add flags parameter to iomap_page_create()
  mm: Add balance_dirty_pages_ratelimited_flags() function
  mm: Move updates of dirty_exceeded into one place
  mm: Move starting of background writeback into the main balancing loop

Pull io_uring updates from Jens Axboe:

 - As per (valid) complaint in the last merge window, fs/io_uring.c has
   grown quite large these days. io_uring isn't really tied to fs
   either, as it supports a wide variety of functionality outside of
   that.

   Move the code to io_uring/ and split it into files that either
   implement a specific request type, and split some code into helpers
   as well. The code is organized a lot better like this, and io_uring.c
   is now < 4K LOC (me).

 - Deprecate the epoll_ctl opcode. It'll still work, just trigger a
   warning once if used. If we don't get any complaints on this, and I
   don't expect any, then we can fully remove it in a future release
   (me).

 - Improve the cancel hash locking (Hao)

 - kbuf cleanups (Hao)

 - Efficiency improvements to the task_work handling (Dylan, Pavel)

 - Provided buffer improvements (Dylan)

 - Add support for recv/recvmsg multishot support. This is similar to
   the accept (or poll) support for have for multishot, where a single
   SQE can trigger everytime data is received. For applications that
   expect to do more than a few receives on an instantiated socket, this
   greatly improves efficiency (Dylan).

 - Efficiency improvements for poll handling (Pavel)

 - Poll cancelation improvements (Pavel)

 - Allow specifiying a range for direct descriptor allocations (Pavel)

 - Cleanup the cqe32 handling (Pavel)

 - Move io_uring types to greatly cleanup the tracing (Pavel)

 - Tons of great code cleanups and improvements (Pavel)

 - Add a way to do sync cancelations rather than through the sqe -> cqe
   interface, as that's a lot easier to use for some use cases (me).

 - Add support to IORING_OP_MSG_RING for sending direct descriptors to a
   different ring. This avoids the usually problematic SCM case, as we
   disallow those. (me)

 - Make the per-command alloc cache we use for apoll generic, place
   limits on it, and use it for netmsg as well (me).

 - Various cleanups (me, Michal, Gustavo, Uros)

* tag 'for-5.20/io_uring-2022-07-29' of git://git.kernel.dk/linux-block: (172 commits)
  io_uring: ensure REQ_F_ISREG is set async offload
  net: fix compat pointer in get_compat_msghdr()
  io_uring: Don't require reinitable percpu_ref
  io_uring: fix types in io_recvmsg_multishot_overflow
  io_uring: Use atomic_long_try_cmpxchg in __io_account_mem
  io_uring: support multishot in recvmsg
  net: copy from user before calling __get_compat_msghdr
  net: copy from user before calling __copy_msghdr
  io_uring: support 0 length iov in buffer select in compat
  io_uring: fix multishot ending when not polled
  io_uring: add netmsg cache
  io_uring: impose max limit on apoll cache
  io_uring: add abstraction around apoll cache
  io_uring: move apoll cache to poll.c
  io_uring: consolidate hash_locked io-wq handling
  io_uring: clear REQ_F_HASH_LOCKED on hash removal
  io_uring: don't race double poll setting REQ_F_ASYNC_DATA
  io_uring: don't miss setting REQ_F_DOUBLE_POLL
  io_uring: disable multishot recvmsg
  io_uring: only trace one of complete or overflow
  ...

Pull turbostat updates from Len Brown:
 "Only updating the turbostat tool here, no kernel changes"

* 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  tools/power turbostat: version 2022.07.28
  tools/power turbostat: do not decode ACC for ICX and SPR
  tools/power turbostat: fix SPR PC6 limits
  tools/power turbostat: cleanup 'automatic_cstate_conversion_probe()'
  tools/power turbostat: separate SPR from ICX
  tools/power turbosstat: fix comment
  tools/power turbostat: Support RAPTORLAKE P
  tools/power turbostat: add support for ALDERLAKE_N
  tools/power turbostat: dump secondary Turbo-Ratio-Limit
  tools/power turbostat: simplify dump_turbo_ratio_limits()
  tools/power turbostat: dump CPUID.7.EDX.Hybrid
  tools/power turbostat: update turbostat.8
  tools/power turbostat: Show uncore frequency
  tools/power turbostat: Fix file pointer leak
  tools/power turbostat: replace strncmp with single character compare
  tools/power turbostat: print the kernel boot commandline
  tools/power turbostat: Introduce support for RaptorLake