blk-mq: remove blk_mq_alloc_tag_set_tags

There is no point in trying to share any code with the realloc case when
all that is needed by the initial tagset allocation is a simple
kcalloc_node.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221109100811.2413423-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

bfq: ignore oom_bfqq in bfq_check_waker

oom_bfqq is just a fallback bfqq, so shouldn't be used with waker
detection.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221108181030.1611703-2-khazhy@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

bfq: fix waker_bfqq inconsistency crash

This fixes crashes in bfq_add_bfqq_busy due to waker_bfqq being NULL,
but woken_list_node still being hashed. This would happen when
bfq_init_rq() expects a brand new allocated queue to be returned from
bfq_get_bfqq_handle_split() and unconditionally updates waker_bfqq
without resetting woken_list_node. Since we can always return oom_bfqq
when attempting to allocate, we cannot assume waker_bfqq starts as NULL.

Avoid setting woken_bfqq for oom_bfqq entirely, as it's not useful.

Crashes would have a stacktrace like:
[160595.656560]  bfq_add_bfqq_busy+0x110/0x1ec
[160595.661142]  bfq_add_request+0x6bc/0x980
[160595.666602]  bfq_insert_request+0x8ec/0x1240
[160595.671762]  bfq_insert_requests+0x58/0x9c
[160595.676420]  blk_mq_sched_insert_request+0x11c/0x198
[160595.682107]  blk_mq_submit_bio+0x270/0x62c
[160595.686759]  __submit_bio_noacct_mq+0xec/0x178
[160595.691926]  submit_bio+0x120/0x184
[160595.695990]  ext4_mpage_readpages+0x77c/0x7c8
[160595.701026]  ext4_readpage+0x60/0xb0
[160595.705158]  filemap_read_page+0x54/0x114
[160595.711961]  filemap_fault+0x228/0x5f4
[160595.716272]  do_read_fault+0xe0/0x1f0
[160595.720487]  do_fault+0x40/0x1c8

Tested by injecting random failures into bfq_get_queue, crashes go away
completely.

Fixes: 8ef3fc3a043c ("block, bfq: make shared queues inherit wakers")
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221108181030.1611703-1-khazhy@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drbd: Store op in drbd_peer_request

(Sort of) cherry-picked from the out-of-tree drbd9 branch. Original
commit message by Joel Colledge:

    This simplifies drbd_submit_peer_request by removing most of the
    arguments. It also makes the treatment of the op better aligned with
    that in struct bio.

    Determine fault_type dynamically using information which is already
    available instead of passing it in as a parameter.

Note: The opf in receive_rs_deallocated was changed from
REQ_OP_WRITE_ZEROES to REQ_OP_DISCARD. This was required in the
out-of-tree module, and does not matter in-tree. The opf is ignored
anyway in drbd_submit_peer_request, since the discard/zero-out is
decided by the EE_TRIM flag.

Signed-off-by: Joel Colledge <joel.colledge@linbit.com>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20221109133453.51652-4-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drbd: disable discard support if granularity > max

The discard_granularity describes the minimum unit of a discard.
If that is larger than the maximal discard size, we need to disable
discards completely.

Reviewed-by: Joel Colledge <joel.colledge@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20221109133453.51652-3-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drbd: use blk_queue_max_discard_sectors helper

We currently only set q->limits.max_discard_sectors, but that is not
enough. Another field, max_hw_discard_sectors, was introduced in
commit 0034af036554 ("block: make /sys/block/<dev>/queue/discard_max_bytes
writeable").

The difference is that max_discard_sectors can be changed from user
space via sysfs, while max_hw_discard_sectors is the "hardware" upper
limit.

So use this helper, which sets both.

This is also a fixup for commit 998e9cbcd615 ("drbd: cleanup
decide_on_discard_support"): if discards are not supported, that does
not necessarily mean we also want to disable write_zeroes.

Fixes: 998e9cbcd615 ("drbd: cleanup decide_on_discard_support")
Reviewed-by: Joel Colledge <joel.colledge@linbit.com>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20221109133453.51652-2-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

ABI: sysfs-bus-pci: add documentation for p2pmem allocate

Add documentation for the p2pmem/allocate binary file which allows
for allocating p2pmem buffers in userspace for passing to drivers
that support them. (Currently only O_DIRECT to NVMe devices.)

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-10-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

PCI/P2PDMA: Allow userspace VMA allocations through sysfs

Create a sysfs bin attribute called "allocate" under the existing
"p2pmem" group. The only allowable operation on this file is the mmap()
call.

When mmap() is called on this attribute, the kernel allocates a chunk of
memory from the genalloc and inserts the pages into the VMA. The
dev_pagemap .page_free callback will indicate when these pages are no
longer used and they will be put back into the genalloc.

On device unbind, remove the sysfs file before the memremap_pages are
cleaned up. This ensures unmap_mapping_range() is called on the files
inode and no new mappings can be created.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-9-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: set FOLL_PCI_P2PDMA in bio_map_user_iov()

When a bio's queue supports PCI P2PDMA, set FOLL_PCI_P2PDMA for
iov_iter_get_pages_flags(). This allows PCI P2PDMA pages to be
passed from userspace and enables the NVMe passthru requests to
use P2PDMA pages.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-8-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: set FOLL_PCI_P2PDMA in __bio_iov_iter_get_pages()

When a bio's queue supports PCI P2PDMA, set FOLL_PCI_P2PDMA for
iov_iter_get_pages_flags(). This allows PCI P2PDMA pages to be passed
from userspace and enables the O_DIRECT path in iomap based filesystems
and direct to block devices.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-7-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

lib/scatterlist: add check when merging zone device pages

Consecutive zone device pages should not be merged into the same sgl
or bvec segment with other types of pages or if they belong to different
pgmaps. Otherwise getting the pgmap of a given segment is not possible
without scanning the entire segment. This helper returns true either if
both pages are not zone device pages or both pages are zone device
pages with the same pgmap.

Factor out the check for page mergability into a pages_are_mergable()
helper and add a check with zone_device_pages_are_mergeable().

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-6-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: add check when merging zone device pages

Consecutive zone device pages should not be merged into the same sgl
or bvec segment with other types of pages or if they belong to different
pgmaps. Otherwise getting the pgmap of a given segment is not possible
without scanning the entire segment. This helper returns true either if
both pages are not zone device pages or both pages are zone device
pages with the same pgmap.

Add a helper to determine if zone device pages are mergeable and use
this helper in page_is_mergeable().

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-5-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

iov_iter: introduce iov_iter_get_pages_[alloc_]flags()

Add iov_iter_get_pages_flags() and iov_iter_get_pages_alloc_flags()
which take a flags argument that is passed to get_user_pages_fast().

This is so that FOLL_PCI_P2PDMA can be passed when appropriate.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221021174116.7200-4-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mm: introduce FOLL_PCI_P2PDMA to gate getting PCI P2PDMA pages

GUP Callers that expect PCI P2PDMA pages can now set FOLL_PCI_P2PDMA to
allow obtaining P2PDMA pages. If GUP is called without the flag and a
P2PDMA page is found, it will return an error in try_grab_page() or
try_grab_folio().

The check is safe to do before taking the reference to the page in both
cases seeing the page should be protected by either the appropriate
ptl or mmap_lock; or the gup fast guarantees preventing TLB flushes.

try_grab_folio() has one call site that WARNs on failure and cannot
actually deal with the failure of this function (it seems it will
get into an infinite loop). Expand the comment there to document a
couple more conditions on why it will not fail.

FOLL_PCI_P2PDMA cannot be set if FOLL_LONGTERM is set. This is to copy
fsdax until pgmap refcounts are fixed (see the link below for more
information).

Link: https://lkml.kernel.org/r/Yy4Ot5MoOhsgYLTQ@ziepe.ca
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-3-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mm: allow multiple error returns in try_grab_page()

In order to add checks for P2PDMA memory into try_grab_page(), expand
the error return from a bool to an int/error code. Update all the
callsites handle change in usage.

Also remove the WARN_ON_ONCE() call at the callsites seeing there
already is a WARN_ON_ONCE() inside the function if it fails.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221021174116.7200-2-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Fix some kernel-doc comments

Remove the description of @required_features in elevator_match()
to clear the below warning:

block/elevator.c:103: warning: Excess function parameter 'required_features' description in 'elevator_match'

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2734
Fixes: ffb86425ee2c ("block: don't check for required features in elevator_match")
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/20221107062255.2685-1-yang.lee@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: use if-else instead of goto in blk_mq_alloc_cached_request()

if-else is more readable than goto here.

Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Link: https://lore.kernel.org/r/d3306fa4e92dc9cc614edc8f1802686096bafef2.1667356813.git.nickyc975@zju.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: improve error handling in blk_mq_alloc_rq_map()

Use goto-style error handling like we do elsewhere in the kernel.

Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Link: https://lore.kernel.org/r/bbbc2d9b17b137798c7fb92042141ca4cbbc58cc.1667356813.git.nickyc975@zju.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: use blk_mq_[un]quiesce_tagset

All controller namespaces share the same tagset, so we can use this
interface which does the optimal operation for parallel quiesce based on
the tagset type(e.g. blocking tagsets and non-blocking tagsets).

nvme connect_q should not be quiesced when quiesce tagset, so set the
QUEUE_FLAG_SKIP_TAGSET_QUIESCE to skip it when init connect_q.

Currently we use NVME_NS_STOPPED to ensure pairing quiescing and
unquiescing. If use blk_mq_[un]quiesce_tagset, NVME_NS_STOPPED will be
invalided, so introduce NVME_CTRL_STOPPED to replace NVME_NS_STOPPED.
In addition, we never really quiesce a single namespace. It is a better
choice to move the flag from ns to ctrl.

Signed-off-by: Chao Leng <lengchao@huawei.com>
[hch: rebased on top of prep patches]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: add tagset quiesce interface

Drivers that have shared tagsets may need to quiesce potentially a lot
of request queues that all share a single tagset (e.g. nvme). Add an
interface to quiesce all the queues on a given tagset. This interface is
useful because it can speedup the quiesce by doing it in parallel.

Because some queues should not need to be quiesced (e.g. the nvme
connect_q) when quiescing the tagset, introduce a
QUEUE_FLAG_SKIP_TAGSET_QUIESCE flag to allow this new interface to
ski quiescing a particular queue.

Signed-off-by: Chao Leng <lengchao@huawei.com>
[hch: simplify for the per-tag_set srcu_struct]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: pass a tagset to blk_mq_wait_quiesce_done

Nothing in blk_mq_wait_quiesce_done needs the request_queue now, so just
pass the tagset, and move the non-mq check into the only caller that
needs it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: move the srcu_struct used for quiescing to the tagset

All I/O submissions have fairly similar latencies, and a tagset-wide
quiesce is a fairly common operation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-12-hch@lst.de
[axboe: fix whitespace]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: skip non-mq queues in blk_mq_quiesce_queue

For submit_bio based queues there is no (S)RCU critical section during
I/O submission and thus nothing to wait for in blk_mq_wait_quiesce_done,
so skip doing any synchronization.  No non-mq driver should be calling
this, but for now we have core callers that unconditionally call into it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-apple: don't unquiesce the I/O queues in apple_nvme_reset_work

apple_nvme_reset_work schedules apple_nvme_remove, to be called, which
will call apple_nvme_disable and unquiesce the I/O queues.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-pci: don't unquiesce the I/O queues in nvme_remove_dead_ctrl

nvme_remove_dead_ctrl schedules nvme_remove to be called, which will
call nvme_dev_disable and unquiesce the I/O queues.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: split nvme_kill_queues

nvme_kill_queues does two things:

 1) mark the gendisk of all namespaces dead
 2) unquiesce all I/O queues

These used to be be intertwined due to block layer issues, but aren't
any more.  So move the unquiscing of the I/O queues into the callers,
and rename the rest of the function to the now more descriptive
nvme_mark_namespaces_dead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: don't unquiesce the admin queue in nvme_kill_queues

None of the callers of nvme_kill_queues needs it to unquiesce the
admin queues, as all of them already do it themselves:

 1) nvme_reset_work explicit call nvme_start_admin_queue toward the
    beginning of the function.  The extra call to nvme_start_admin_queue
    in nvme_reset_work this won't do anything as
    NVME_CTRL_ADMIN_Q_STOPPED will already be cleared.
 2) nvme_remove calls nvme_dev_disable with shutdown flag set to true at
    the very beginning of the function if the PCIe device was not present,
    which is the precondition for the call to nvme_kill_queues.
    nvme_dev_disable already calls nvme_start_admin_queue toward the
    end of the function when the shutdown flag is set to true, so the
    admin queue is already enabled at this point.
 3) nvme_remove_dead_ctrl schedules a workqueue to unbind the driver,
    which will end up in nvme_remove, which calls nvme_dev_disable with
    the shutdown flag.  This case will call nvme_start_admin_queue a bit
    later than before.
 4) apple_nvme_remove uses the same sequence as nvme_remove_dead_ctrl
    above.
 5) nvme_remove_namespaces only calls nvme_kill_queues when the
    controller is in the DEAD state.  That can only happen in the PCIe
    driver, and only from nvme_remove. See item 2) above for the
    conditions there.

So it is safe to just remove the call to nvme_start_admin_queue in
nvme_kill_queues without replacement.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove the NVME_NS_DEAD check in nvme_validate_ns

At the point where namespaces are marked dead, the controller is in a
non-live state and we won't get pass the identify commands.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: remove the NVME_NS_DEAD check in nvme_remove_invalid_namespaces

The NVME_NS_DEAD check only made sense when we revalidated namespaces
in nvme_passthrough_end for commands that affected the namespace inventory.
These days NVME_NS_DEAD is only set during reset or when tearing down
namespaces, and we always remove all namespaces right after that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme: don't remove namespaces in nvme_passthru_end

The call to nvme_remove_invalid_namespaces made sense when
nvme_passthru_end revalidated all namespaces and had to remove those that
didn't exist any more.  Since we don't revalidate from nvme_passthru_end
now, this call is entirely spurious.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-pci: refactor the tagset handling in nvme_reset_work

The code to create, update or delete a tagset and namespaces in
nvme_reset_work is a bit convoluted.  Refactor it with a two high-level
conditionals for first probe vs reset and I/O queues vs no I/O queues
to make the code flow more clear.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-3-hch@lst.de
[axboe: fix whitespace issue]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: set the disk capacity to 0 in blk_mark_disk_dead

nvme and xen-blkfront are already doing this to stop buffered writes from
creating dirty pages that can't be written out later.  Move it to the
common code.

This also removes the comment about the ordering from nvme, as bd_mutex
not only is gone entirely, but also hasn't been used for locking updates
to the disk size long before that, and thus the ordering requirement
documented there doesn't apply any more.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: don't declare 'bfqd' as type 'void *' in bfq_group

Prevent unnecessary format conversion for bfqg->bfqd in multiple
places.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: remove dead code for updating 'rq_in_driver'

Such code are not even compiled since they are inside marco "#if 0".

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: cleanup bfq_activate_requeue_entity()

Just make the code a litter cleaner by removing the unnecessary
variable 'sd'.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: factor out code to update 'active_entities'

Current code is a bit ugly and hard to read.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: remove set but not used variable in __bfq_entity_update_weight_prio

After the patch "block, bfq: cleanup bfq_weights_tree add/remove apis"),
the local variable 'bfqd' is not used anymore, thus remove it.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20221102022542.3621219-2-yukuai1@huaweicloud.com
Fixes: afdba1461262 ("block, bfq: cleanup bfq_weights_tree add/remove apis")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Replace struct rq_depth with unsigned int in struct iolatency_grp

We only need a max queue depth for every iolatency to limit the inflight io
number. Replace struct rq_depth with unsigned int to simplfy "struct
iolatency_grp" and save memory.

Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20221018111240.22612-4-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Correct comment for scale_cookie_change

Default queue depth of iolatency_grp is unlimited, so we scale down
quickly(once by half) in scale_cookie_change. Remove the "subtract
1/16th" part which is not the truth and add the actual way we
scale down.

Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221018111240.22612-3-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Remove redundant parent blkcg_gp check in check_scale_change

Function blkcg_iolatency_throttle will make sure blkg->parent is not
NULL before calls check_scale_change. And function check_scale_change
is only called in blkcg_iolatency_throttle.

Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20221018111240.22612-2-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: split elevator_switch

Split an elevator_disable helper from elevator_switch for the case where
we want to switch to no scheduler at all.  This includes removing the
pointless elevator_switch_mq helper and removing the switch to no
schedule logic from blk_mq_init_sched.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: don't check for required features in elevator_match

Checking for the required features in the callers simplifies the code
quite a bit, so do that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-7-hch@lst.de
[axboe: adjust for dropping patch 1, use __elevator_find()]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: simplify the check for the current elevator in elv_iosched_show

Just compare the pointers instead of using the string based
elevator_match.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: cleanup the variable naming in elv_iosched_store

Use eq for the elevator_queue as done elsewhere.  This frees e to be used
for the loop iterator instead of the odd __ prefix.  In addition rename
elv to cur to make it more clear it is the currently selected elevator.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: exit elv_iosched_show early when I/O schedulers are not supported

If the tag_set has BLK_MQ_F_NO_SCHED flag set we will never show any
scheduler, so exit early.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: cleanup elevator_get

Do the request_module and repeated lookup in the only caller that cares,
pick a saner name that explains where are actually doing a lookup and
use a sane calling conventions that passes the queue first.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: cleanup __bfq_weights_tree_remove()

It's the same with bfq_weights_tree_remove() now.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-7-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: cleanup bfq_weights_tree add/remove apis

The 'bfq_data' and 'rb_root_cached' can both be accessed through
'bfq_queue', thus only pass 'bfq_queue' as parameter.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: do not idle if only one group is activated

Now that root group is counted into 'num_groups_with_pending_reqs',
'num_groups_with_pending_reqs > 0' is always true in
bfq_asymmetric_scenario(). Thus change the condition to '> 1'.

On the other hand, this change can enable concurrent sync io if only
one group is activated.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: refactor the counting of 'num_groups_with_pending_reqs'

Currently, bfq can't handle sync io concurrently as long as they
are not issued from root group. This is because
'bfqd->num_groups_with_pending_reqs > 0' is always true in
bfq_asymmetric_scenario().

The way that bfqg is counted into 'num_groups_with_pending_reqs':

Before this patch:
 1) root group will never be counted.
 2) Count if bfqg or it's child bfqgs have pending requests.
 3) Don't count if bfqg and it's child bfqgs complete all the requests.

After this patch:
 1) root group is counted.
 2) Count if bfqg have pending requests.
 3) Don't count if bfqg complete all the requests.

With this change, the occasion that only one group is activated can be
detected, and next patch will support concurrent sync io in the
occasion.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: record how many queues have pending requests

Prepare to refactor the counting of 'num_groups_with_pending_reqs'.

Add a counter in bfq_group, update it while tracking if bfqq have pending
requests and when bfq_bfqq_move() is called.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block, bfq: support to track if bfqq has pending requests

If entity belongs to bfqq, then entity->in_groups_with_pending_reqs
is not used currently. This patch use it to track if bfqq has pending
requests through callers of weights_tree insertion and removal.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: remove redundant call to blk_freeze_queue_start in blk_mq_destroy_queue

The calling relationship in blk_mq_destroy_queue() is as follows:

blk_mq_destroy_queue()
    ...
    -> blk_queue_start_drain()
        -> blk_freeze_queue_start()  <- called
        ...
    -> blk_freeze_queue()
        -> blk_freeze_queue_start()  <- called again
        -> blk_mq_freeze_queue_wait()
    ...

So there is a redundant call to blk_freeze_queue_start().

Replace blk_freeze_queue() with blk_mq_freeze_queue_wait() to avoid the
redundant call.

Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030083212.1251255-1-nickyc975@zju.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: move queue_is_mq out of blk_mq_cancel_work_sync

The only caller that needs queue_is_mq check is del_gendisk, so move the
check into it.

Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030094730.1275463-1-nickyc975@zju.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: simplify blksize_bits() implementation

Convert current looping-based implementation into bit operation,
which can bring improvement for:

1) bitops is more efficient for its arch-level optimization.

2) Given that blksize_bits() is inline, _if_ @size is compile-time
constant, it's possible that order_base_2() _may_ make output
compile-time evaluated, depending on code context and compiler behavior.

Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/TYCP286MB23238842958D7C083D6B67CECA349@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: avoid double ->queue_rq() because of early timeout

David Jeffery found one double ->queue_rq() issue, so far it can
be triggered in VM use case because of long vmexit latency or preempt
latency of vCPU pthread or long page fault in vCPU pthread, then block
IO req could be timed out before queuing the request to hardware but after
calling blk_mq_start_request() during ->queue_rq(), then timeout handler
may handle it by requeue, then double ->queue_rq() is caused, and kernel
panic.

So far, it is driver's responsibility to cover the race between timeout
and completion, so it seems supposed to be solved in driver in theory,
given driver has enough knowledge.

But it is really one common problem, lots of driver could have similar
issue, and could be hard to fix all affected drivers, even it isn't easy
for driver to handle the race. So David suggests this patch by draining
in-progress ->queue_rq() for solving this issue.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: virtualization@lists.linux-foundation.org
Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221026051957.358818-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Micro-optimize get_max_segment_size()

This patch removes a conditional jump from get_max_segment_size(). The
x86-64 assembler code for this function without this patch is as follows:

206             return min_not_zero(mask - offset + 1,
   0x0000000000000118 <+72>:    not    %rax
   0x000000000000011b <+75>:    and    0x8(%r10),%rax
   0x000000000000011f <+79>:    add    $0x1,%rax
   0x0000000000000123 <+83>:    je     0x138 <bvec_split_segs+104>
   0x0000000000000125 <+85>:    cmp    %rdx,%rax
   0x0000000000000128 <+88>:    mov    %rdx,%r12
   0x000000000000012b <+91>:    cmovbe %rax,%r12
   0x000000000000012f <+95>:    test   %rdx,%rdx
   0x0000000000000132 <+98>:    mov    %eax,%edx
   0x0000000000000134 <+100>:   cmovne %r12d,%edx

With this patch applied:

206             return min(mask - offset, (unsigned long)lim->max_segment_size - 1) + 1;
   0x000000000000003f <+63>:    mov    0x28(%rdi),%ebp
   0x0000000000000042 <+66>:    not    %rax
   0x0000000000000045 <+69>:    and    0x8(%rdi),%rax
   0x0000000000000049 <+73>:    sub    $0x1,%rbp
   0x000000000000004d <+77>:    cmp    %rbp,%rax
   0x0000000000000050 <+80>:    cmova  %rbp,%rax
   0x0000000000000054 <+84>:    add    $0x1,%eax

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221025191755.1711437-4-bvanassche@acm.org
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Constify most queue limits pointers

Document which functions do not modify the queue limits.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221025191755.1711437-3-bvanassche@acm.org
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Remove request.write_hint

Commit c75e707fe1aa ("block: remove the per-bio/request write hint")
removed all code that uses the struct request write_hint member. Hence
also remove 'write_hint' itself.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221025191755.1711437-2-bvanassche@acm.org
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove bio_start_io_acct_time

bio_start_io_acct_time is not actually used anywhere, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221025155916.270303-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-apple: remove an extra queue reference

Now that blk_mq_destroy_queue does not release the queue reference, there
is no need for a second admin queue reference to be held by the
apple_nvme structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Sven Peter <sven@svenpeter.dev>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20221018135720.670094-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvme-pci: remove an extra queue reference

Now that blk_mq_destroy_queue does not release the queue reference, there
is no need for a second admin queue reference to be held by the nvme_dev.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20221018135720.670094-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: remove an extra queue reference

Now that blk_mq_destroy_queue does not release the queue reference, there
is no need for a second queue reference to be held by the scsi_device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20221018135720.670094-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-mq: move the call to blk_put_queue out of blk_mq_destroy_queue

The fact that blk_mq_destroy_queue also drops a queue reference leads
to various places having to grab an extra reference.  Move the call to
blk_put_queue into the callers to allow removing the extra references.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20221018135720.670094-2-hch@lst.de
[axboe: fix fabrics_q vs admin_q conflict in nvme core.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: fix up elevator_type refcounting

The current reference management logic of io scheduler modules contains
refcnt problems. For example, blk_mq_init_sched may fail before or after
the calling of e->ops.init_sched. If it fails before the calling, it does
nothing to the reference to the io scheduler module. But if it fails after
the calling, it releases the reference by calling kobject_put(&eq->kobj).

As the callers of blk_mq_init_sched can't know exactly where the failure
happens, they can't handle the reference to the io scheduler module
properly: releasing the reference on failure results in double-release if
blk_mq_init_sched has released it, and not releasing the reference results
in ghost reference if blk_mq_init_sched did not release it either.

The same problem also exists in io schedulers' init_sched implementations.

We can address the problem by adding releasing statements to the error
handling procedures of blk_mq_init_sched and init_sched implementations.
But that is counterintuitive and requires modifications to existing io
schedulers.

Instead, We make elevator_alloc get the io scheduler module references
that will be released by elevator_release. And then, we match each
elevator_get with an elevator_put. Therefore, each reference to an io
scheduler module explicitly has its own getter and releaser, and we no
longer need to worry about the refcnt problems.

The bugs and the patch can be validated with tools here:
https://github.com/nickyc975/linux_elv_refcnt_bug.git

[hch: split out a few bits into separate patches, use a non-try
      module_get in elevator_alloc]

Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: check for an unchanged elevator earlier in __elevator_change

No need to find the actual elevator_type struct for this comparism,
the name is all that is needed.

Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: sanitize the elevator name before passing it to __elevator_change

The stripped name should also be used for the none check.  To do so
strip it in the caller and pass in the sanitized name.  Drop the pointless
__ prefix in the function name while we're at it.

Based on a patch from Jinlong Chen <nickyc975@zju.edu.cn>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: add proper helpers for elevator_type module refcount management

Make sure we have helpers for all relevant module refcount operations on
the elevator_type in elevator.h, and use them.  Move the call to the get
helper in blk_mq_elv_switch_none a bit so that it is obvious with a less
verbose comment.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-wbt: don't enable throttling if default elevator is bfq

Commit b5dc5d4d1f4f ("block,bfq: Disable writeback throttling") tries to
disable wbt for bfq, it's done by calling wbt_disable_default() in
bfq_init_queue(). However, wbt is still enabled if default elevator is
bfq:

device_add_disk
 elevator_init_mq
  bfq_init_queue
   wbt_disable_default -> done nothing

 blk_register_queue
  wbt_enable_default -> wbt is enabled

Fix the problem by adding a new flag ELEVATOR_FLAG_DISBALE_WBT, bfq
will set the flag in bfq_init_queue, and following wbt_enable_default()
won't enable wbt while the flag is set.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-7-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

elevator: add new field flags in struct elevator_queue

There are only one flag to indicate that elevator is registered currently,
prepare to add a flag to disable wbt if default elevator is bfq.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-wbt: don't show valid wbt_lat_usec in sysfs while wbt is disabled

Currently, if wbt is initialized and then disabled by
wbt_disable_default(), sysfs will still show valid wbt_lat_usec, which
will confuse users that wbt is still enabled.

This patch shows wbt_lat_usec as zero if it's disabled.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reported-and-tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-wbt: make enable_state more accurate

Currently, if user disable wbt through sysfs, 'enable_state' will be
'WBT_STATE_ON_MANUAL', which will be confusing. Add a new state
'WBT_STATE_OFF_MANUAL' to cover that case.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-wbt: remove unnecessary check in wbt_enable_default()

If CONFIG_BLK_WBT_MQ is disabled, wbt_init() won't do anything.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

elevator: remove redundant code in elv_unregister_queue()

"elevator_queue *e" is already declared and initialized in the beginning
of elv_unregister_queue().

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221019121518.3865235-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-iocost: read 'ioc->params' inside 'ioc->lock' in ioc_timer_fn()

'ioc->params' is updated in ioc_refresh_params(), which is proteced by
'ioc->lock', however, ioc_timer_fn() read params outside the lock.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-iocost: prevent configuration update concurrent with io throttling

This won't cause any severe problem currently, however, this doesn't
seems appropriate:

1) 'ioc->params' is read from multiple places without holding
'ioc->lock', unexpected value might be read if writing it concurrently.

2) If configuration is changed while io is throttling, the functionality
might be affected. For example, if module params is updated and cost
becomes smaller, waiting for timer that is caculated under old
configuration is not appropriate.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-iocost: don't release 'ioc->lock' while updating params

ioc_qos_write() and ioc_cost_model_write() are the same:

1) hold lock to read 'ioc->params' to local variable;
2) update params to local variable without lock;
3) hold lock to write local variable to 'ioc->params';

In theroy, if user updates params concurrenty, the params might be lost:

t1: update params a t2: update params b
spin_lock_irq(&ioc->lock);
memcpy(qos, ioc->params.qos, sizeof(qos))
spin_unlock_irq(&ioc->lock);

qos[a] = xxx;

spin_lock_irq(&ioc->lock);
memcpy(qos, ioc->params.qos, sizeof(qos))
spin_unlock_irq(&ioc->lock);

qos[b] = xxx;

spin_lock_irq(&ioc->lock);
memcpy(ioc->params.qos, qos, sizeof(qos));
ioc_refresh_params(ioc, true);
spin_unlock_irq(&ioc->lock);

spin_lock_irq(&ioc->lock);
// updates of a will be lost
memcpy(ioc->params.qos, qos, sizeof(qos));
ioc_refresh_params(ioc, true);
spin_unlock_irq(&ioc->lock);

Althrough this is not common case, the problem can by fixed easily by
holding the lock through the read, update, write process.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

blk-iocost: disable writeback throttling

Commit b5dc5d4d1f4f ("block,bfq: Disable writeback throttling") disable
wbt for bfq, because different write-throttling heuristics should not
work together.

For the same reason, wbt and iocost should not work together as well,
unless admin really want to do that, dispite that performance is
affected.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Linux 6.1-rc2

Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "RISC-V:

   - Fix compilation without RISCV_ISA_ZICBOM

   - Fix kvm_riscv_vcpu_timer_pending() for Sstc

  ARM:

   - Fix a bug preventing restoring an ITS containing mappings for very
     large and very sparse device topology

   - Work around a relocation handling error when compiling the nVHE
     object with profile optimisation

   - Fix for stage-2 invalidation holding the VM MMU lock for too long
     by limiting the walk to the largest block mapping size

   - Enable stack protection and branch profiling for VHE

   - Two selftest fixes

  x86:

   - add compat implementation for KVM_X86_SET_MSR_FILTER ioctl

  selftests:

   - synchronize includes between include/uapi and tools/include/uapi"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  tools: include: sync include/api/linux/kvm.h
  KVM: x86: Add compat handler for KVM_X86_SET_MSR_FILTER
  KVM: x86: Copy filter arg outside kvm_vm_ioctl_set_msr_filter()
  kvm: Add support for arch compat vm ioctls
  RISC-V: KVM: Fix kvm_riscv_vcpu_timer_pending() for Sstc
  RISC-V: Fix compilation without RISCV_ISA_ZICBOM
  KVM: arm64: vgic: Fix exit condition in scan_its_table()
  KVM: arm64: nvhe: Fix build with profile optimization
  KVM: selftests: Fix number of pages for memory slot in memslot_modification_stress_test
  KVM: arm64: selftests: Fix multiple versions of GIC creation
  KVM: arm64: Enable stack protection and branch profiling for VHE
  KVM: arm64: Limit stage2_apply_range() batch size to largest block
  KVM: arm64: Work out supported block level at compile time

Revert "mfd: syscon: Remove repetition of the regmap_get_val_endian()"

This reverts commit 72a95859728a7866522e6633818bebc1c2519b17.

It broke reboots on big-endian MIPS and MIPS64 malta QEMU instances,
which use the syscon driver.  Little-endian is not effected, which means
likely it's important to handle regmap_get_val_endian() in this function
after all.

Fixes: 72a95859728a ("mfd: syscon: Remove repetition of the regmap_get_val_endian()")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Lee Jones <lee@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/utsname_sysctl.c: Fix hostname polling

Commit bfca3dd3d068 ("kernel/utsname_sysctl.c: print kernel arch") added
a new entry to the uts_kern_table[] array, but didn't update the
UTS_PROC_xyz enumerators of older entries, breaking anything that used
them.

Which is admittedly not many cases: it's really just the two uses of
uts_proc_notify() in kernel/sys.c.  But apparently journald-systemd
actually uses this to detect hostname changes.

Reported-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Fixes: bfca3dd3d068 ("kernel/utsname_sysctl.c: print kernel arch")
Link: https://lore.kernel.org/lkml/0c2b92a6-0f25-9538-178f-eee3b06da23f@secunet.com/
Link: https://linux-regtracking.leemhuis.info/regzbot/regression/0c2b92a6-0f25-9538-178f-eee3b06da23f@secunet.com/
Cc: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'perf_urgent_for_v6.1_rc2' of git://git./linux/kernel/git/tip/tip

Pull perf fixes from Borislav Petkov:

 - Fix raw data handling when perf events are used in bpf

 - Rework how SIGTRAPs get delivered to events to address a bunch of
   problems with it. Add a selftest for that too

* tag 'perf_urgent_for_v6.1_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bpf: Fix sample_flags for bpf_perf_event_output
  selftests/perf_events: Add a SIGTRAP stress test with disables
  perf: Fix missing SIGTRAPs

Merge tag 'sched_urgent_for_v6.1_rc2' of git://git./linux/kernel/git/tip/tip

Pull scheduler fixes from Borislav Petkov:

 - Adjust code to not trip up CFI

 - Fix sched group cookie matching

* tag 'sched_urgent_for_v6.1_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Introduce struct balance_callback to avoid CFI mismatches
  sched/core: Fix comparison in sched_group_cookie_match()

Merge tag 'objtool_urgent_for_v6.1_rc2' of git://git./linux/kernel/git/tip/tip

Pull objtool fix from Borislav Petkov:

 - Fix ORC stack unwinding when GCOV is enabled

* tag 'objtool_urgent_for_v6.1_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/unwind/orc: Fix unreliable stack dump with gcov

Merge tag 'x86_urgent_for_v6.0_rc2' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:
 "As usually the case, right after a major release, the tip urgent
  branches accumulate a couple more fixes than normal. And here is the
  x86, a bit bigger, urgent pile.

   - Use the correct CPU capability clearing function on the error path
     in Intel perf LBR

   - A CFI fix to ftrace along with a simplification

   - Adjust handling of zero capacity bit mask for resctrl cache
     allocation on AMD

   - A fix to the AMD microcode loader to attempt patch application on
     every logical thread

   - A couple of topology fixes to handle CPUID leaf 0x1f enumeration
     info properly

   - Drop a -mabi=ms compiler option check as both compilers support it
     now anyway

   - A couple of fixes to how the initial, statically allocated FPU
     buffer state is setup and its interaction with dynamic states at
     runtime"

* tag 'x86_urgent_for_v6.0_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Fix copy_xstate_to_uabi() to copy init states correctly
  perf/x86/intel/lbr: Use setup_clear_cpu_cap() instead of clear_cpu_cap()
  ftrace,kcfi: Separate ftrace_stub() and ftrace_stub_graph()
  x86/ftrace: Remove ftrace_epilogue()
  x86/resctrl: Fix min_cbm_bits for AMD
  x86/microcode/AMD: Apply the patch early on every logical thread
  x86/topology: Fix duplicated core ID within a package
  x86/topology: Fix multiple packages shown on a single-package system
  hwmon/coretemp: Handle large core ID value
  x86/Kconfig: Drop check for -mabi=ms for CONFIG_EFI_STUB
  x86/fpu: Exclude dynamic states from init_fpstate
  x86/fpu: Fix the init_fpstate size check with the actual size
  x86/fpu: Configure init_fpstate attributes orderly

Merge tag 'io_uring-6.1-2022-10-22' of git://git.kernel.dk/linux

Pull io_uring follow-up from Jens Axboe:
 "Currently the zero-copy has automatic fallback to normal transmit, and
  it was decided that it'd be cleaner to return an error instead if the
  socket type doesn't support it.

  Zero-copy does work with UDP and TCP, it's more of a future proofing
  kind of thing (eg for samba)"

* tag 'io_uring-6.1-2022-10-22' of git://git.kernel.dk/linux:
  io_uring/net: fail zc sendmsg when unsupported by socket
  io_uring/net: fail zc send when unsupported by socket
  net: flag sockets supporting msghdr originated zerocopy

Merge tag 'hwmon-for-v6.1-rc2' of git://git./linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - corsair-psu: Fix typo in USB id description, and add USB ID for new
   PSU

 - pwm-fan: Fix fan power handling when disabling fan control

* tag 'hwmon-for-v6.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (corsair-psu) Add USB id of the new HX1500i psu
  hwmon: (pwm-fan) Explicitly switch off fan power when setting pwm1_enable to 0
  hwmon: (corsair-psu) fix typo in USB id description

Merge tag 'i2c-for-6.1-rc2' of git://git./linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
 "RPM fix for qcom-cci, platform module alias for xiic, build warning
  fix for mlxbf, typo fixes in comments"

* tag 'i2c-for-6.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: mlxbf: depend on ACPI; clean away ifdeffage
  i2c: fix spelling typos in comments
  i2c: qcom-cci: Fix ordering of pm_runtime_xx and i2c_add_adapter
  i2c: xiic: Add platform module alias

Merge tag 'pci-v6.1-fixes-2' of git://git./linux/kernel/git/helgaas/pci

Pull pci fixes from Bjorn Helgaas:

 - Revert a simplification that broke pci-tegra due to a masking error

 - Update MAINTAINERS for Kishon's email address change and TI
   DRA7XX/J721E maintainer change

* tag 'pci-v6.1-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  MAINTAINERS: Update Kishon's email address in PCI endpoint subsystem
  MAINTAINERS: Add Vignesh Raghavendra as maintainer of TI DRA7XX/J721E PCI driver
  Revert "PCI: tegra: Use PCI_CONF1_EXT_ADDRESS() macro"

Merge tag 'media/v6.1-2' of git://git./linux/kernel/git/mchehab/linux-media

Pull missed media updates from Mauro Carvalho Chehab:
 "It seems I screwed-up my previous pull request: it ends up that only
  half of the media patches that were in linux-next got merged in -rc1.

  The script which creates the signed tags silently failed due to
  5.19->6.0 so it ended generating a tag with incomplete stuff.

  So here are the missing parts:

   - a DVB core security fix

   - lots of fixes and cleanups for atomisp staging driver

   - old drivers that are VB1 are being moved to staging to be
     deprecated

   - several driver updates - mostly for embedded systems, but there are
     also some things addressing issues with some PC webcams, in the UVC
     video driver"

* tag 'media/v6.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (163 commits)
  media: sun6i-csi: Move csi buffer definition to main header file
  media: sun6i-csi: Introduce and use video helper functions
  media: sun6i-csi: Add media ops with link notify callback
  media: sun6i-csi: Remove controls handler from the driver
  media: sun6i-csi: Register the media device after creation
  media: sun6i-csi: Pass and store csi device directly in video code
  media: sun6i-csi: Tidy up video code
  media: sun6i-csi: Tidy up v4l2 code
  media: sun6i-csi: Tidy up Kconfig
  media: sun6i-csi: Use runtime pm for clocks and reset
  media: sun6i-csi: Define and use variant to get module clock rate
  media: sun6i-csi: Always set exclusive module clock rate
  media: sun6i-csi: Tidy up platform code
  media: sun6i-csi: Refactor main driver data structures
  media: sun6i-csi: Define and use driver name and (reworked) description
  media: cedrus: Add a Kconfig dependency on RESET_CONTROLLER
  media: sun8i-rotate: Add a Kconfig dependency on RESET_CONTROLLER
  media: sun8i-di: Add a Kconfig dependency on RESET_CONTROLLER
  media: sun4i-csi: Add a Kconfig dependency on RESET_CONTROLLER
  media: sun6i-csi: Add a Kconfig dependency on RESET_CONTROLLER
  ...

io_uring/net: fail zc sendmsg when unsupported by socket

The previous patch fails zerocopy send requests for protocols that don't
support it, do the same for zerocopy sendmsg.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0854e7bb4c3d810a48ec8b5853e2f61af36a0467.1666346426.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

io_uring/net: fail zc send when unsupported by socket

If a protocol doesn't support zerocopy it will silently fall back to
copying. This type of behaviour has always been a source of troubles
so it's better to fail such requests instead.

Cc: <stable@vger.kernel.org> # 6.0
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2db3c7f16bb6efab4b04569cd16e6242b40c5cb3.1666346426.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

net: flag sockets supporting msghdr originated zerocopy

We need an efficient way in io_uring to check whether a socket supports
zerocopy with msghdr provided ubuf_info. Add a new flag into the struct
socket flags fields.

Cc: <stable@vger.kernel.org> # 6.0
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/3dafafab822b1c66308bb58a0ac738b1e3f53f74.1666346426.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

hwmon: (corsair-psu) Add USB id of the new HX1500i psu

Also update the documentation accordingly.

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/Y0FghqQCHG/cX5Jz@monster.localdomain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

tools: include: sync include/api/linux/kvm.h

Provide a definition of KVM_CAP_DIRTY_LOG_RING_ACQ_REL.

Fixes: 17601bfed909 ("KVM: Add KVM_CAP_DIRTY_LOG_RING_ACQ_REL capability and config option")
Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Add compat handler for KVM_X86_SET_MSR_FILTER

The KVM_X86_SET_MSR_FILTER ioctls contains a pointer in the passed in
struct which means it has a different struct size depending on whether
it gets called from 32bit or 64bit code.

This patch introduces compat code that converts from the 32bit struct to
its 64bit counterpart which then gets used going forward internally.
With this applied, 32bit QEMU can successfully set MSR bitmaps when
running on 64bit kernels.

Reported-by: Andrew Randrianasulu <randrianasulu@gmail.com>
Fixes: 1a155254ff937 ("KVM: x86: Introduce MSR filtering")
Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20221017184541.2658-4-graf@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86: Copy filter arg outside kvm_vm_ioctl_set_msr_filter()

In the next patch we want to introduce a second caller to
set_msr_filter() which constructs its own filter list on the stack.
Refactor the original function so it takes it as argument instead of
reading it through copy_from_user().

Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20221017184541.2658-3-graf@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

kvm: Add support for arch compat vm ioctls

We will introduce the first architecture specific compat vm ioctl in the
next patch. Add all necessary boilerplate to allow architectures to
override compat vm ioctls when necessary.

Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20221017184541.2658-2-graf@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Merge tag 'kvm-riscv-fixes-6.1-1' of https://github.com/kvm-riscv/linux into HEAD

KVM/riscv fixes for 6.1, take #1

- Fix compilation without RISCV_ISA_ZICBOM
- Fix kvm_riscv_vcpu_timer_pending() for Sstc