So far bio is marked as REQ_POLLED if RWF_HIPRI/IOCB_HIPRI is passed
from userspace sync io interface, then block layer tries to poll until
the bio is completed. But the current implementation calls
blk_io_schedule() if bio_poll() returns 0, and this way causes io hang or
timeout easily.

But looks no one reports this kind of issue, which should have been
triggered in normal io poll sanity test or blktests block/007 as
observed by Changhui, that means it is very likely that no one uses it
or no one cares it.

Also after io_uring is invented, io poll for sync dio becomes legacy
interface.

So ignore RWF_HIPRI hint for sync dio.

CC: linux-mm@kvack.org
Cc: linux-xfs@vger.kernel.org
Reported-by: NChanghui Zhong <czhong@redhat.com>
Suggested-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Tested-by: NChanghui Zhong <czhong@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220420143110.2679002-1-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Get rid of the following redundant assignments:
- to a variable r_cols from function ldm_parse_cmp3
- to variables r_id1 and r_id2 from functions ldm_parse_dgr3 and ldm_parse_dgr4
- to a variable r_index from function ldm_parse_prt3
that end up in values not being read until the end of function.

Reported by clang-tidy [deadcode.DeadStores]
Signed-off-by: NMichal Orzel <michalorzel.eng@gmail.com>
Link: https://lore.kernel.org/r/20220423113811.13335-5-michalorzel.eng@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Get rid of redundant assignment to a variable part_fmt from function
atari_partition. It is being assigned a value that is never read until
the end of function.

Reported by clang-tidy [deadcode.DeadStores]
Signed-off-by: NMichal Orzel <michalorzel.eng@gmail.com>
Link: https://lore.kernel.org/r/20220423113811.13335-4-michalorzel.eng@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Get rid of redundant assignments to a variable slot from function
adfspart_check_ADFS. It is being assigned a value that is never read
as we are breaking out from the switch case and the function ends.

Reported by clang-tidy [deadcode.DeadStores]
Signed-off-by: NMichal Orzel <michalorzel.eng@gmail.com>
Link: https://lore.kernel.org/r/20220423113811.13335-3-michalorzel.eng@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Get rid of redundant assignment to a variable ret from function
bio_map_user_iov as it is being assigned a value that is never read.
It is being re-assigned in the first instruction after the while loop

Reported by clang-tidy [deadcode.DeadStores]
Signed-off-by: NMichal Orzel <michalorzel.eng@gmail.com>
Link: https://lore.kernel.org/r/20220423113811.13335-2-michalorzel.eng@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Get rid of redundant assignments to a variable sectors from functions
badblocks_check and badblocks_clear. This variable, that is a function
parameter, is being assigned a value that is never read until the end of
function.

Reported by clang-tidy [deadcode.DeadStores]
Signed-off-by: NMichal Orzel <michalorzel.eng@gmail.com>
Link: https://lore.kernel.org/r/20220423113811.13335-1-michalorzel.eng@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Export IO accounting interfaces in terms of block_device now that
gendisk has become more internal to block core.

Rename __part_{start,end}_io_acct's first argument from part to bdev.
Rename __part_{start,end}_io_acct to bdev_{start,end}_io_acct and
export them.  Remove disk_{start,end}_io_acct and update caller (zram)
to use bdev_{start,end}_io_acct.

DM can now be updated to use bdev_{start,end}_io_acct.
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NMike Snitzer <snitzer@kernel.org>
Link: https://lore.kernel.org/r/20220418022733.56168-2-snitzer@kernel.orgSigned-off-by: NJens Axboe <axboe@kernel.dk>

Randomly poking into block device internals for manual prefetches isn't
exactly a very maintainable thing to do.  And none of the performance
critical direct I/O implementations still use this library function
anyway, so just drop it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDamien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20220415045258.199825-28-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Secure erase is a very different operation from discard in that it is
a data integrity operation vs hint.  Fully split the limits and helper
infrastructure to make the separation more clear.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> [nifs2]
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org> [f2fs]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: NChao Yu <chao@kernel.org>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-27-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Abstract away implementation details from file systems by providing a
block_device based helper to retrieve the discard granularity.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: NRyusuke Konishi <konishi.ryusuke@gmail.com>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Link: https://lore.kernel.org/r/20220415045258.199825-26-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Just use a non-zero max_discard_sectors as an indicator for discard
support, similar to what is done for write zeroes.

The only places where needs special attention is the RAID5 driver,
which must clear discard support for security reasons by default,
even if the default stacking rules would allow for it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add a helper to query the number of sectors support per each discard bio
based on the block device and use this helper to stop various places from
poking into the request_queue to see if discard is supported and if so how
much.  This mirrors what is done e.g. for write zeroes as well.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-24-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Move all the logic to limit the discard bio size into a common helper
so that it is better documented.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: NColy Li <colyli@suse.de>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-23-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

No need to inline these fairly larger helpers.  Also fix the return value
to be unsigned, just like the field in struct queue_limits.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220415045258.199825-22-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Use the bdev based alignment helper instead of open coding it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220415045258.199825-21-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Just use bdev_alignment_offset in disk_discard_alignment_show instead.
That helpers is the same except for an always false branch that doesn't
matter in this slow path.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220415045258.199825-20-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

No need to inline these fairly larger helpers.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220415045258.199825-19-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

This does the same as the open coded variant except for an extra branch,
and allows to remove queue_alignment_offset entirely.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220415045258.199825-18-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Replace the open coded offset calculation with the proper helper.
This is an ABI change in that the -1 for a misaligned partition is
properly propagated, which can be considered a bug fix and matches
what is done on the whole device.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-17-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add a helper to check the max supported sectors for zone append based on
the block_device instead of having to poke into the block layer internal
request_queue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NDamien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-16-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add a helper to check the stable writes flag based on the block_device
instead of having to poke into the block layer internal request_queue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-15-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add a helper to check the FUA flag based on the block_device instead of
having to poke into the block layer internal request_queue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-14-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add a helper to check the write cache flag based on the block_device
instead of having to poke into the block layer internal request_queue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-13-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Add a helper to check the nonrot flag based on the block_device instead
of having to poke into the block layer internal request_queue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-12-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Use the bdev based helper instead of poking into the queue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDamien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-11-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220415045258.199825-10-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: NDavid Sterba <dsterba@suse.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-9-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Sanitize the calling conventions and use a goto label to cleanup the
code flow.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NChristoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20220415045258.199825-8-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

The bdev version does the right thing for partitions, so use that.

Fixes: 9104d31a ("drbd: introduce WRITE_SAME support")
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NChristoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20220415045258.199825-7-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Use the bdev based limits helpers where they exist.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NChristoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20220415045258.199825-6-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Fold each branch into its only caller.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NChristoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20220415045258.199825-5-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Use the proper bdev_discard_alignment helper that accounts for partition
offsets.

Fixes: c66ac9db ("[SCSI] target: Add LIO target core v4.0.0-rc6")
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-4-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

The SCSI target drivers is a consumer of the block layer and shoul
d generally work on struct block_device.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-3-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

For block devices, the SCSI target drivers implements UNMAP as calls to
blkdev_issue_discard, which does not guarantee zeroing just because
Write Zeroes is supported.

Note that this does not affect the file backed path which uses
fallocate to punch holes.

Fixes: 2237498f ("target/iblock: Convert WRITE_SAME to blkdev_issue_zeroout")
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-2-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

Bios queued into BFQ IO scheduler can be associated with a cgroup that
was already offlined. This may then cause insertion of this bfq_group
into a service tree. But this bfq_group will get freed as soon as last
bio associated with it is completed leading to use after free issues for
service tree users. Fix the problem by making sure we always operate on
online bfq_group. If the bfq_group associated with the bio is not
online, we pick the first online parent.

CC: stable@vger.kernel.org
Fixes: e21b7a0b ("block, bfq: add full hierarchical scheduling and cgroups support")
Tested-by: N"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-9-jack@suse.czSigned-off-by: NJens Axboe <axboe@kernel.dk>

BFQ usage of __bio_blkcg() is a relict from the past. Furthermore if bio
would not be associated with any blkcg, the usage of __bio_blkcg() in
BFQ is prone to races with the task being migrated between cgroups as
__bio_blkcg() calls at different places could return different blkcgs.

Convert BFQ to the new situation where bio->bi_blkg is initialized in
bio_set_dev() and thus practically always valid. This allows us to save
blkcg_gq lookup and noticeably simplify the code.

CC: stable@vger.kernel.org
Fixes: 0fe061b9 ("blkcg: fix ref count issue with bio_blkcg() using task_css")
Tested-by: N"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-8-jack@suse.czSigned-off-by: NJens Axboe <axboe@kernel.dk>

Track whether bfq_group is still online. We cannot rely on
blkcg_gq->online because that gets cleared only after all policies are
offlined and we need something that gets updated already under
bfqd->lock when we are cleaning up our bfq_group to be able to guarantee
that when we see online bfq_group, it will stay online while we are
holding bfqd->lock lock.

CC: stable@vger.kernel.org
Tested-by: N"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-7-jack@suse.czSigned-off-by: NJens Axboe <axboe@kernel.dk>

We call bfq_init_rq() from request merging functions where requests we
get should have already gone through bfq_init_rq() during insert and
anyway we want to do anything only if the request is already tracked by
BFQ. So replace calls to bfq_init_rq() with RQ_BFQQ() instead to simply
skip requests untracked by BFQ. We move bfq_init_rq() call in
bfq_insert_request() a bit earlier to cover request merging and thus
can transfer FIFO position in case of a merge.

CC: stable@vger.kernel.org
Tested-by: N"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-6-jack@suse.czSigned-off-by: NJens Axboe <axboe@kernel.dk>

In bfq_insert_request() we unlock bfqd->lock only to call
trace_block_rq_insert() and then lock bfqd->lock again. This is really
pointless since tracing is disabled if we really care about performance
and even if the tracepoint is enabled, it is a quick call.

CC: stable@vger.kernel.org
Tested-by: N"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-5-jack@suse.czSigned-off-by: NJens Axboe <axboe@kernel.dk>

When the process is migrated to a different cgroup (or in case of
writeback just starts submitting bios associated with a different
cgroup) bfq_merge_bio() can operate with stale cgroup information in
bic. Thus the bio can be merged to a request from a different cgroup or
it can result in merging of bfqqs for different cgroups or bfqqs of
already dead cgroups and causing possible use-after-free issues. Fix the
problem by updating cgroup information in bfq_merge_bio().

CC: stable@vger.kernel.org
Fixes: e21b7a0b ("block, bfq: add full hierarchical scheduling and cgroups support")
Tested-by: N"yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-4-jack@suse.czSigned-off-by: NJens Axboe <axboe@kernel.dk>