Commit Graph

6591 Commits

Author SHA1 Message Date
Bart Van Assche
d55450b96f block/mq-deadline: Fix the tag reservation code
commit 39823b47bb upstream.

The current tag reservation code is based on a misunderstanding of the
meaning of data->shallow_depth. Fix the tag reservation code as follows:
* By default, do not reserve any tags for synchronous requests because
  for certain use cases reserving tags reduces performance. See also
  Harshit Mogalapalli, [bug-report] Performance regression with fio
  sequential-write on a multipath setup, 2024-03-07
  (https://lore.kernel.org/linux-block/5ce2ae5d-61e2-4ede-ad55-551112602401@oracle.com/)
* Reduce min_shallow_depth to one because min_shallow_depth must be less
  than or equal any shallow_depth value.
* Scale dd->async_depth from the range [1, nr_requests] to [1,
  bits_per_sbitmap_word].

Cc: Christoph Hellwig <hch@lst.de>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Zhiguo Niu <zhiguo.niu@unisoc.com>
Fixes: 07757588e5 ("block/mq-deadline: Reserve 25% of scheduler tags for synchronous requests")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240509170149.7639-3-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:53:02 +02:00
Bart Van Assche
9c18787ec3 block: Call .limit_depth() after .hctx has been set
commit 6259151c04 upstream.

Call .limit_depth() after data->hctx has been set such that data->hctx can
be used in .limit_depth() implementations.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Zhiguo Niu <zhiguo.niu@unisoc.com>
Fixes: 07757588e5 ("block/mq-deadline: Reserve 25% of scheduler tags for synchronous requests")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240509170149.7639-2-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:53:02 +02:00
Christoph Hellwig
d418313bd8 block: initialize integrity buffer to zero before writing it to media
[ Upstream commit 899ee2c382 ]

Metadata added by bio_integrity_prep is using plain kmalloc, which leads
to random kernel memory being written media.  For PI metadata this is
limited to the app tag that isn't used by kernel generated metadata,
but for non-PI metadata the entire buffer leaks kernel memory.

Fix this by adding the __GFP_ZERO flag to allocations for writes.

Fixes: 7ba1ba12ee ("block: Block layer data integrity support")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-03 08:48:53 +02:00
Jinyoung Choi
a9a99a1ca1 block: cleanup bio_integrity_prep
[ Upstream commit 51d74ec9b6 ]

If a problem occurs in the process of creating an integrity payload, the
status of bio is always BLK_STS_RESOURCE.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jinyoung Choi <j-young.choi@samsung.com>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20230725051839epcms2p8e4d20ad6c51326ad032e8406f59d0aaa@epcms2p8
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 899ee2c382 ("block: initialize integrity buffer to zero before writing it to media")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-03 08:48:53 +02:00
Nitesh Shetty
5e0cde523f block: refactor to use helper
[ Upstream commit 8f63fef586 ]

Reduce some code by making use of bio_integrity_bytes().

Signed-off-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20230719121608.32105-1-nj.shetty@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 899ee2c382 ("block: initialize integrity buffer to zero before writing it to media")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-03 08:48:53 +02:00
Justin Stitt
61ec76ec93 block/ioctl: prefer different overflow check
[ Upstream commit ccb326b5f9 ]

Running syzkaller with the newly reintroduced signed integer overflow
sanitizer shows this report:

[   62.982337] ------------[ cut here ]------------
[   62.985692] cgroup: Invalid name
[   62.986211] UBSAN: signed-integer-overflow in ../block/ioctl.c:36:46
[   62.989370] 9pnet_fd: p9_fd_create_tcp (7343): problem connecting socket to 127.0.0.1
[   62.992992] 9223372036854775807 + 4095 cannot be represented in type 'long long'
[   62.997827] 9pnet_fd: p9_fd_create_tcp (7345): problem connecting socket to 127.0.0.1
[   62.999369] random: crng reseeded on system resumption
[   63.000634] GUP no longer grows the stack in syz-executor.2 (7353): 20002000-20003000 (20001000)
[   63.000668] CPU: 0 PID: 7353 Comm: syz-executor.2 Not tainted 6.8.0-rc2-00035-gb3ef86b5a957 #1
[   63.000677] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   63.000682] Call Trace:
[   63.000686]  <TASK>
[   63.000731]  dump_stack_lvl+0x93/0xd0
[   63.000919]  __get_user_pages+0x903/0xd30
[   63.001030]  __gup_longterm_locked+0x153e/0x1ba0
[   63.001041]  ? _raw_read_unlock_irqrestore+0x17/0x50
[   63.001072]  ? try_get_folio+0x29c/0x2d0
[   63.001083]  internal_get_user_pages_fast+0x1119/0x1530
[   63.001109]  iov_iter_extract_pages+0x23b/0x580
[   63.001206]  bio_iov_iter_get_pages+0x4de/0x1220
[   63.001235]  iomap_dio_bio_iter+0x9b6/0x1410
[   63.001297]  __iomap_dio_rw+0xab4/0x1810
[   63.001316]  iomap_dio_rw+0x45/0xa0
[   63.001328]  ext4_file_write_iter+0xdde/0x1390
[   63.001372]  vfs_write+0x599/0xbd0
[   63.001394]  ksys_write+0xc8/0x190
[   63.001403]  do_syscall_64+0xd4/0x1b0
[   63.001421]  ? arch_exit_to_user_mode_prepare+0x3a/0x60
[   63.001479]  entry_SYSCALL_64_after_hwframe+0x6f/0x77
[   63.001535] RIP: 0033:0x7f7fd3ebf539
[   63.001551] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
[   63.001562] RSP: 002b:00007f7fd32570c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   63.001584] RAX: ffffffffffffffda RBX: 00007f7fd3ff3f80 RCX: 00007f7fd3ebf539
[   63.001590] RDX: 4db6d1e4f7e43360 RSI: 0000000020000000 RDI: 0000000000000004
[   63.001595] RBP: 00007f7fd3f1e496 R08: 0000000000000000 R09: 0000000000000000
[   63.001599] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[   63.001604] R13: 0000000000000006 R14: 00007f7fd3ff3f80 R15: 00007ffd415ad2b8
...
[   63.018142] ---[ end trace ]---

Historically, the signed integer overflow sanitizer did not work in the
kernel due to its interaction with `-fwrapv` but this has since been
changed [1] in the newest version of Clang; It was re-enabled in the
kernel with Commit 557f8c582a ("ubsan: Reintroduce signed overflow
sanitizer").

Let's rework this overflow checking logic to not actually perform an
overflow during the check itself, thus avoiding the UBSAN splat.

[1]: https://github.com/llvm/llvm-project/pull/82432

Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240507-b4-sio-block-ioctl-v3-1-ba0c2b32275e@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:46:15 +02:00
Yu Kuai
9a97008dbf block: support to account io_ticks precisely
[ Upstream commit 99dc422335 ]

Currently, io_ticks is accounted based on sampling, specifically
update_io_ticks() will always account io_ticks by 1 jiffies from
bdev_start_io_acct()/blk_account_io_start(), and the result can be
inaccurate, for example(HZ is 250):

Test script:
fio -filename=/dev/sda -bs=4k -rw=write -direct=1 -name=test -thinktime=4ms

Test result: util is about 90%, while the disk is really idle.

This behaviour is introduced by commit 5b18b5a737 ("block: delete
part_round_stats and switch to less precise counting"), however, there
was a key point that is missed that this patch also improve performance
a lot:

Before the commit:
part_round_stats:
  if (part->stamp != now)
   stats |= 1;

  part_in_flight()
  -> there can be lots of task here in 1 jiffies.
  part_round_stats_single()
   __part_stat_add()
  part->stamp = now;

After the commit:
update_io_ticks:
  stamp = part->bd_stamp;
  if (time_after(now, stamp))
   if (try_cmpxchg())
    __part_stat_add()
    -> only one task can reach here in 1 jiffies.

Hence in order to account io_ticks precisely, we only need to know if
there are IO inflight at most once in one jiffies. Noted that for
rq-based device, iterating tags should not be used here because
'tags->lock' is grabbed in blk_mq_find_and_get_req(), hence
part_stat_lock_inc/dec() and part_in_flight() is used to trace inflight.
The additional overhead is quite little:

 - per cpu add/dec for each IO for rq-based device;
 - per cpu sum for each jiffies;

And it's verified by null-blk that there are no performance degration
under heavy IO pressure.

Fixes: 5b18b5a737 ("block: delete part_round_stats and switch to less precise counting")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240509123717.3223892-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:07 +02:00
Chaitanya Kulkarni
56aacead05 block: open code __blk_account_io_done()
[ Upstream commit 06965037ce ]

There is only one caller for __blk_account_io_done(), the function
is small enough to fit in its caller blk_account_io_done().

Remove the function and opencode in the its caller
blk_account_io_done().

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230327073427.4403-2-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 99dc422335 ("block: support to account io_ticks precisely")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:06 +02:00
Chaitanya Kulkarni
4e4c9bf71a block: open code __blk_account_io_start()
[ Upstream commit e165fb4dd6 ]

There is only one caller for __blk_account_io_start(), the function
is small enough to fit in its caller blk_account_io_start().

Remove the function and opencode in the its caller
blk_account_io_start().

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230327073427.4403-2-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 99dc422335 ("block: support to account io_ticks precisely")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:03:06 +02:00
Rik van Riel
f6add0a6f7 blk-iocost: avoid out of bounds shift
[ Upstream commit beaa51b360 ]

UBSAN catches undefined behavior in blk-iocost, where sometimes
iocg->delay is shifted right by a number that is too large,
resulting in undefined behavior on some architectures.

[  186.556576] ------------[ cut here ]------------
UBSAN: shift-out-of-bounds in block/blk-iocost.c:1366:23
shift exponent 64 is too large for 64-bit type 'u64' (aka 'unsigned long long')
CPU: 16 PID: 0 Comm: swapper/16 Tainted: G S          E    N 6.9.0-0_fbk700_debug_rc2_kbuilder_0_gc85af715cac0 #1
Hardware name: Quanta Twin Lakes MP/Twin Lakes Passive MP, BIOS F09_3A23 12/08/2020
Call Trace:
 <IRQ>
 dump_stack_lvl+0x8f/0xe0
 __ubsan_handle_shift_out_of_bounds+0x22c/0x280
 iocg_kick_delay+0x30b/0x310
 ioc_timer_fn+0x2fb/0x1f80
 __run_timer_base+0x1b6/0x250
...

Avoid that undefined behavior by simply taking the
"delay = 0" branch if the shift is too large.

I am not sure what the symptoms of an undefined value
delay will be, but I suspect it could be more than a
little annoying to debug.

Signed-off-by: Rik van Riel <riel@surriel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Jens Axboe <axboe@kernel.dk>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20240404123253.0f58010f@imladris.surriel.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:56:07 +02:00
Li Nan
8a26198186 block: fix overflow in blk_ioctl_discard()
[ Upstream commit 22d24a544b ]

There is no check for overflow of 'start + len' in blk_ioctl_discard().
Hung task occurs if submit an discard ioctl with the following param:
  start = 0x80000000000ff000, len = 0x8000000000fff000;
Add the overflow validation now.

Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240329012319.2034550-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:56:05 +02:00
Roman Smirnov
512a01da71 block: prevent division by zero in blk_rq_stat_sum()
[ Upstream commit 93f52fbeaf ]

The expression dst->nr_samples + src->nr_samples may
have zero value on overflow. It is necessary to add
a check to avoid division by zero.

Found by Linux Verification Center (linuxtesting.org) with Svace.

Signed-off-by: Roman Smirnov <r.smirnov@omp.ru>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/20240305134509.23108-1-r.smirnov@omp.ru
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-13 13:05:12 +02:00
Damien Le Moal
244cb8200e block: Do not force full zone append completion in req_bio_endio()
commit 55251fbdf0 upstream.

This reverts commit 748dc0b65e.

Partial zone append completions cannot be supported as there is no
guarantees that the fragmented data will be written sequentially in the
same manner as with a full command. Commit 748dc0b65e ("block: fix
partial zone append completion handling in req_bio_endio()") changed
req_bio_endio() to always advance a partially failed BIO by its full
length, but this can lead to incorrect accounting. So revert this
change and let low level device drivers handle this case by always
failing completely zone append operations. With this revert, users will
still see an IO error for a partially completed zone append BIO.

Fixes: 748dc0b65e ("block: fix partial zone append completion handling in req_bio_endio()")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240328004409.594888-2-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:19:49 +02:00
Chengming Zhou
052e4c8987 blk-mq: release scheduler resource when request completes
commit e5c0ca1365 upstream.

Chuck reported [1] an IO hang problem on NFS exports that reside on SATA
devices and bisected to commit 615939a2ae ("blk-mq: defer to the normal
submission path for post-flush requests").

We analysed the IO hang problem, found there are two postflush requests
waiting for each other.

The first postflush request completed the REQ_FSEQ_DATA sequence, so go to
the REQ_FSEQ_POSTFLUSH sequence and added in the flush pending list, but
failed to blk_kick_flush() because of the second postflush request which
is inflight waiting in scheduler queue.

The second postflush waiting in scheduler queue can't be dispatched because
the first postflush hasn't released scheduler resource even though it has
completed by itself.

Fix it by releasing scheduler resource when the first postflush request
completed, so the second postflush can be dispatched and completed, then
make blk_kick_flush() succeed.

While at it, remove the check for e->ops.finish_request, as all
schedulers set that. Reaffirm this requirement by adding a WARN_ON_ONCE()
at scheduler registration time, just like we do for insert_requests and
dispatch_request.

[1] https://lore.kernel.org/all/7A57C7AE-A51A-4254-888B-FE15CA21F9E9@oracle.com/

Link: https://lore.kernel.org/linux-block/20230819031206.2744005-1-chengming.zhou@linux.dev/
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202308172100.8ce4b853-oliver.sang@intel.com
Fixes: 615939a2ae ("blk-mq: defer to the normal submission path for post-flush requests")
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://lore.kernel.org/r/20230813152325.3017343-1-chengming.zhou@linux.dev
[axboe: folded in incremental fix and added tags]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[bvanassche: changed RQF_USE_SCHED into RQF_ELVPRIV; restored the
finish_request pointer check before calling finish_request and removed
the new warning from the elevator code. This patch fixes an I/O hang
when submitting a REQ_FUA request to a request queue for a zoned block
device for which FUA has been disabled (QUEUE_FLAG_FUA is not set).]
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:19:46 +02:00
Tony Battersby
242006996d block: Fix page refcounts for unaligned buffers in __bio_release_pages()
commit 38b43539d6 upstream.

Fix an incorrect number of pages being released for buffers that do not
start at the beginning of a page.

Fixes: 1b151e2435 ("block: Remove special-casing of compound pages")
Cc: stable@vger.kernel.org
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Tested-by: Greg Edwards <gedwards@ddn.com>
Link: https://lore.kernel.org/r/86e592a9-98d4-4cff-a646-0c0084328356@cybernetics.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[ Tony: backport to v6.1 by replacing bio_release_page() loop with
  folio_put_refs() as commits fd363244e8 and e4cc64657b are not
  present. ]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03 15:19:46 +02:00
Bart Van Assche
af4b1a5aa0 Revert "block/mq-deadline: use correct way to throttling write requests"
[ Upstream commit 256aab46e3 ]

The code "max(1U, 3 * (1U << shift)  / 4)" comes from the Kyber I/O
scheduler. The Kyber I/O scheduler maintains one internal queue per hwq
and hence derives its async_depth from the number of hwq tags. Using
this approach for the mq-deadline scheduler is wrong since the
mq-deadline scheduler maintains one internal queue for all hwqs
combined. Hence this revert.

Cc: stable@vger.kernel.org
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Cc: Zhiguo Niu <Zhiguo.Niu@unisoc.com>
Fixes: d47f9717e5 ("block/mq-deadline: use correct way to throttling write requests")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240313214218.1736147-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:19:37 +02:00
Damien Le Moal
5ea241b193 block: Clear zone limits for a non-zoned stacked queue
[ Upstream commit c8f6f88d25 ]

Device mapper may create a non-zoned mapped device out of a zoned device
(e.g., the dm-zoned target). In such case, some queue limit such as the
max_zone_append_sectors and zone_write_granularity endup being non zero
values for a block device that is not zoned. Avoid this by clearing
these limits in blk_stack_limits() when the stacked zoned limit is
false.

Fixes: 3093a47972 ("block: inherit the zoned characteristics in blk_stack_limits")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240222131724.1803520-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:19:27 +02:00
Greg Joyce
6fb80b3e75 block: sed-opal: handle empty atoms when parsing response
[ Upstream commit 5429c8de56 ]

The SED Opal response parsing function response_parse() does not
handle the case of an empty atom in the response. This causes
the entry count to be too high and the response fails to be
parsed. Recognizing, but ignoring, empty atoms allows response
handling to succeed.

Signed-off-by: Greg Joyce <gjoyce@linux.ibm.com>
Link: https://lore.kernel.org/r/20240216210417.3526064-2-gjoyce@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:20:26 -04:00
Christian A. Ehrhardt
8fc8087410 block: Fix WARNING in _copy_from_iter
[ Upstream commit 13f3956eb5 ]

Syzkaller reports a warning in _copy_from_iter because an
iov_iter is supposedly used in the wrong direction. The reason
is that syzcaller managed to generate a request with
a transfer direction of SG_DXFER_TO_FROM_DEV. This instructs
the kernel to copy user buffers into the kernel, read into
the copied buffers and then copy the data back to user space.

Thus the iovec is used in both directions.

Detect this situation in the block layer and construct a new
iterator with the correct direction for the copy-in.

Reported-by: syzbot+a532b03fdfee2c137666@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/0000000000009b92c10604d7a5e9@google.com/t/
Reported-by: syzbot+63dec323ac56c28e644f@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/0000000000003faaa105f6e7c658@google.com/T/
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240121202634.275068-1-lk@c--e.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:25 +01:00
Damien Le Moal
e7d2e87abc block: fix partial zone append completion handling in req_bio_endio()
[ Upstream commit 748dc0b65e ]

Partial completions of zone append request is not allowed but if a zone
append completion indicates a number of completed bytes different from
the original BIO size, only the BIO status is set to error. This leads
to bio_advance() not setting the BIO size to 0 and thus to not call
bio_endio() at the end of req_bio_endio().

Make sure a partially completed zone append is failed and completed
immediately by forcing the completed number of bytes (nbytes) to be
equal to the BIO size, thus ensuring that bio_endio() is called.

Fixes: 297db73184 ("block: fix req_bio_endio append error handling")
Cc: stable@kernel.vger.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240110092942.442334-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-23 09:12:49 +01:00
Jens Axboe
492e0aba08 block: treat poll queue enter similarly to timeouts
commit 33391eecd6 upstream.

We ran into an issue where a production workload would randomly grind to
a halt and not continue until the pending IO had timed out. This turned
out to be a complicated interaction between queue freezing and polled
IO:

1) You have an application that does polled IO. At any point in time,
   there may be polled IO pending.

2) You have a monitoring application that issues a passthrough command,
   which is marked with side effects such that it needs to freeze the
   queue.

3) Passthrough command is started, which calls blk_freeze_queue_start()
   on the device. At this point the queue is marked frozen, and any
   attempt to enter the queue will fail (for non-blocking) or block.

4) Now the driver calls blk_mq_freeze_queue_wait(), which will return
   when the queue is quiesced and pending IO has completed.

5) The pending IO is polled IO, but any attempt to poll IO through the
   normal iocb_bio_iopoll() -> bio_poll() will fail when it gets to
   bio_queue_enter() as the queue is frozen. Rather than poll and
   complete IO, the polling threads will sit in a tight loop attempting
   to poll, but failing to enter the queue to do so.

The end result is that progress for either application will be stalled
until all pending polled IO has timed out. This causes obvious huge
latency issues for the application doing polled IO, but also long delays
for passthrough command.

Fix this by treating queue enter for polled IO just like we do for
timeouts. This allows quick quiesce of the queue as we still poll and
complete this IO, while still disallowing queueing up new IO.

Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-16 19:06:31 +01:00
Tejun Heo
e5dc63f01e blk-iocost: Fix an UBSAN shift-out-of-bounds warning
[ Upstream commit 2a427b49d0 ]

When iocg_kick_delay() is called from a CPU different than the one which set
the delay, @now may be in the past of @iocg->delay_at leading to the
following warning:

  UBSAN: shift-out-of-bounds in block/blk-iocost.c:1359:23
  shift exponent 18446744073709 is too large for 64-bit type 'u64' (aka 'unsigned long long')
  ...
  Call Trace:
   <TASK>
   dump_stack_lvl+0x79/0xc0
   __ubsan_handle_shift_out_of_bounds+0x2ab/0x300
   iocg_kick_delay+0x222/0x230
   ioc_rqos_merge+0x1d7/0x2c0
   __rq_qos_merge+0x2c/0x80
   bio_attempt_back_merge+0x83/0x190
   blk_attempt_plug_merge+0x101/0x150
   blk_mq_submit_bio+0x2b1/0x720
   submit_bio_noacct_nocheck+0x320/0x3e0
   __swap_writepage+0x2ab/0x9d0

The underflow itself doesn't really affect the behavior in any meaningful
way; however, the past timestamp may exaggerate the delay amount calculated
later in the code, which shouldn't be a material problem given the nature of
the delay mechanism.

If @now is in the past, this CPU is racing another CPU which recently set up
the delay and there's nothing this CPU can contribute w.r.t. the delay.
Let's bail early from iocg_kick_delay() in such cases.

Reported-by: Breno Leitão <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 5160a5a53c ("blk-iocost: implement delay adjustment hysteresis")
Link: https://lore.kernel.org/r/ZVvc9L_CYk5LO1fT@slm.duckdns.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-16 19:06:29 +01:00
Ming Lei
1d9c777d3e blk-mq: fix IO hang from sbitmap wakeup race
[ Upstream commit 5266caaf56 ]

In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered
with the following blk_mq_get_driver_tag() in case of getting driver
tag failure.

Then in __sbitmap_queue_wake_up(), waitqueue_active() may not observe
the added waiter in blk_mq_mark_tag_wait() and wake up nothing, meantime
blk_mq_mark_tag_wait() can't get driver tag successfully.

This issue can be reproduced by running the following test in loop, and
fio hang can be observed in < 30min when running it on my test VM
in laptop.

	modprobe -r scsi_debug
	modprobe scsi_debug delay=0 dev_size_mb=4096 max_queue=1 host_max_queue=1 submit_queues=4
	dev=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter*/host*/target*/*/block/* | head -1 | xargs basename`
	fio --filename=/dev/"$dev" --direct=1 --rw=randrw --bs=4k --iodepth=1 \
       		--runtime=100 --numjobs=40 --time_based --name=test \
        	--ioengine=libaio

Fix the issue by adding one explicit barrier in blk_mq_mark_tag_wait(), which
is just fine in case of running out of tag.

Cc: Jan Kara <jack@suse.cz>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Reported-by: Changhui Zhong <czhong@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20240112122626.4181044-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:12:59 +00:00
Christoph Hellwig
8ae4201900 block: prevent an integer overflow in bvec_try_merge_hw_page
[ Upstream commit 3f034c374a ]

Reordered a check to avoid a possible overflow when adding len to bv_len.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20231204173419.782378-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:12:53 +00:00
Li Lingfeng
9564767b67 block: Move checking GENHD_FL_NO_PART to bdev_add_partition()
[ Upstream commit 7777f47f2e ]

Commit 1a721de848 ("block: don't add or resize partition on the disk
with GENHD_FL_NO_PART") prevented all operations about partitions on disks
with GENHD_FL_NO_PART in blkpg_do_ioctl() since they are meaningless.
However, it changed error code in some scenarios. So move checking
GENHD_FL_NO_PART to bdev_add_partition() to eliminate impact.

Fixes: 1a721de848 ("block: don't add or resize partition on the disk with GENHD_FL_NO_PART")
Reported-by: Allison Karlitskaya <allison.karlitskaya@redhat.com>
Closes: https://lore.kernel.org/all/CAOYeF9VsmqKMcQjo1k6YkGNujwN-nzfxY17N3F-CMikE1tYp+w@mail.gmail.com/
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240118130401.792757-1-lilingfeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-31 16:17:11 -08:00
Matthew Wilcox (Oracle)
9025ee1079 block: Remove special-casing of compound pages
commit 1b151e2435 upstream.

The special casing was originally added in pre-git history; reproducing
the commit log here:

> commit a318a92567d77
> Author: Andrew Morton <akpm@osdl.org>
> Date:   Sun Sep 21 01:42:22 2003 -0700
>
>     [PATCH] Speed up direct-io hugetlbpage handling
>
>     This patch short-circuits all the direct-io page dirtying logic for
>     higher-order pages.  Without this, we pointlessly bounce BIOs up to
>     keventd all the time.

In the last twenty years, compound pages have become used for more than
just hugetlb.  Rewrite these functions to operate on folios instead
of pages and remove the special case for hugetlbfs; I don't think
it's needed any more (and if it is, we can put it back in as a call
to folio_test_hugetlb()).

This was found by inspection; as far as I can tell, this bug can lead
to pages used as the destination of a direct I/O read not being marked
as dirty.  If those pages are then reclaimed by the MM without being
dirtied for some other reason, they won't be written out.  Then when
they're faulted back in, they will not contain the data they should.
It'll take a pretty unusual setup to produce this problem with several
races all going the wrong way.

This problem predates the folio work; it could for example have been
triggered by mmaping a THP in tmpfs and using that as the target of an
O_DIRECT read.

Fixes: 800d8c63b2 ("shmem: add huge pages support")
Cc:  <stable@vger.kernel.org>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-25 15:27:52 -08:00
Jens Axboe
33cf52b6e5 block: ensure we hold a queue reference when using queue limits
[ Upstream commit 7b4f36cd22 ]

q_usage_counter is the only thing preventing us from the limits changing
under us in __bio_split_to_limits, but blk_mq_submit_bio doesn't hold
it while calling into it.

Move the splitting inside the region where we know we've got a queue
reference. Ideally this could still remain a shared section of code, but
let's keep the fix simple and defer any refactoring here to later.

Reported-by: Christoph Hellwig <hch@lst.de>
Fixes: 900e080752 ("block: move queue enter logic into blk_mq_submit_bio()")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:49 -08:00
Min Li
ef31cc8779 block: add check that partition length needs to be aligned with block size
commit 6f64f866aa upstream.

Before calling add partition or resize partition, there is no check
on whether the length is aligned with the logical block size.
If the logical block size of the disk is larger than 512 bytes,
then the partition size maybe not the multiple of the logical block size,
and when the last sector is read, bio_truncate() will adjust the bio size,
resulting in an IO error if the size of the read command is smaller than
the logical block size.If integrity data is supported, this will also
result in a null pointer dereference when calling bio_integrity_free.

Cc:  <stable@vger.kernel.org>
Signed-off-by: Min Li <min15.li@samsung.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230629142517.121241-1-min15.li@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-25 15:27:42 -08:00
Keith Busch
a623d31805 block: make BLK_DEF_MAX_SECTORS unsigned
[ Upstream commit 0a26f327e4 ]

This is used as an unsigned value, so define it that way to avoid
having to cast it.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20230105205146.3610282-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 9a9525de86 ("null_blk: don't cap max_hw_sectors to BLK_DEF_MAX_SECTORS")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:30 -08:00
Li Nan
e765363ecf block: add check of 'minors' and 'first_minor' in device_add_disk()
[ Upstream commit 4c434392c4 ]

'first_minor' represents the starting minor number of disks, and
'minors' represents the number of partitions in the device. Neither
of them can be greater than MINORMASK + 1.

Commit e338924bd0 ("block: check minor range in device_add_disk()")
only added the check of 'first_minor + minors'. However, their sum might
be less than MINORMASK but their values are wrong. Complete the checks now.

Fixes: e338924bd0 ("block: check minor range in device_add_disk()")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231219075942.840255-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:28 -08:00
Li Nan
9f5b79cf12 block: Set memalloc_noio to false on device_add_disk() error path
[ Upstream commit 5fa3d1a00c ]

On the error path of device_add_disk(), device's memalloc_noio flag was
set but not cleared. As the comment of pm_runtime_set_memalloc_noio(),
"The function should be called between device_add() and device_del()".
Clear this flag before device_del() now.

Fixes: 25e823c8c3 ("block/genhd.c: apply pm_runtime_set_memalloc_noio on block devices")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231211075356.1839282-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:27 -08:00
Ming Lei
f84b0c6445 blk-mq: don't count completed flush data request as inflight in case of quiesce
[ Upstream commit 0e4237ae8d ]

Request queue quiesce may interrupt flush sequence, and the original request
may have been marked as COMPLETE, but can't get finished because of
queue quiesce.

This way is fine from driver viewpoint, because flush sequence is block
layer concept, and it isn't related with driver.

However, driver(such as dm-rq) can call blk_mq_queue_inflight() to count &
drain inflight requests, then the wait & drain never gets done because
the completed & not-finished flush request is counted as inflight.

Fix this issue by not counting completed flush data request as inflight in
case of quiesce.

Cc: Mike Snitzer <snitzer@kernel.org>
Cc: David Jeffery <djeffery@redhat.com>
Cc: John Pittman <jpittman@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20231201085605.577730-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-20 11:50:04 +01:00
Christoph Hellwig
bf223fd4d9 block: update the stable_writes flag in bdev_add
[ Upstream commit 1898efcdbe ]

Propagate the per-queue stable_write flags into each bdev inode in bdev_add.
This makes sure devices that require stable writes have it set for I/O
on the block device node as well.

Note that this doesn't cover the case of a flag changing on a live device
yet.  We should handle that as well, but I plan to cover it as part of a
more general rework of how changing runtime paramters on block devices
works.

Fixes: 1cb039f3dc ("bdi: replace BDI_CAP_STABLE_WRITES with a queue and a sb flag")
Reported-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231025141020.192413-3-hch@lst.de
Tested-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:32 +01:00
Christoph Hellwig
b5c8e0ff76 blk-mq: make sure active queue usage is held for bio_integrity_prep()
[ Upstream commit b0077e269f ]

blk_integrity_unregister() can come if queue usage counter isn't held
for one bio with integrity prepared, so this request may be completed with
calling profile->complete_fn, then kernel panic.

Another constraint is that bio_integrity_prep() needs to be called
before bio merge.

Fix the issue by:

- call bio_integrity_prep() with one queue usage counter grabbed reliably

- call bio_integrity_prep() before bio merge

Fixes: 900e080752 ("block: move queue enter logic into blk_mq_submit_bio()")
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Link: https://lore.kernel.org/r/20231113035231.2708053-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:30 +01:00
Sarthak Kukreti
9539e3b56e block: Don't invalidate pagecache for invalid falloc modes
commit 1364a3c391 upstream.

Only call truncate_bdev_range() if the fallocate mode is supported. This
fixes a bug where data in the pagecache could be invalidated if the
fallocate() was called on the block device with an invalid mode.

Fixes: 25f4c41415 ("block: implement (some of) fallocate for block devices")
Cc: stable@vger.kernel.org
Reported-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Fixes: line?  I've never seen those wrapped.
Link: https://lore.kernel.org/r/20231011201230.750105-1-sarthakkukreti@chromium.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-10 17:10:20 +01:00
Ming Lei
94070fd668 blk-cgroup: bypass blkcg_deactivate_policy after destroying
[ Upstream commit e63a573035 ]

blkcg_deactivate_policy() can be called after blkg_destroy_all()
returns, and it isn't necessary since blkg_destroy_all has covered
policy deactivation.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20231117023527.3188627-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-20 17:00:21 +01:00
Ming Lei
e52d0eb48e blk-throttle: fix lockdep warning of "cgroup_mutex or RCU read lock required!"
[ Upstream commit 27b13e209d ]

Inside blkg_for_each_descendant_pre(), both
css_for_each_descendant_pre() and blkg_lookup() requires RCU read lock,
and either cgroup_assert_mutex_or_rcu_locked() or rcu_read_lock_held()
is called.

Fix the warning by adding rcu read lock.

Reported-by: Changhui Zhong <czhong@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20231117023527.3188627-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-20 17:00:21 +01:00
Yu Kuai
46c541fa66 blk-core: use pr_warn_ratelimited() in bio_check_ro()
[ Upstream commit 1b0a151c10 ]

If one of the underlying disks of raid or dm is set to read-only, then
each io will generate new log, which will cause message storm. This
environment is indeed problematic, however we can't make sure our
naive custormer won't do this, hence use pr_warn_ratelimited() to
prevent message storm in this case.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Fixes: 57e95e4670 ("block: fix and cleanup bio_check_ro")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20231107111247.2157820-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:52:17 +01:00
Khazhismel Kumykov
6a5b845b57 blk-throttle: check for overflow in calculate_bytes_allowed
commit 2dd710d476 upstream.

Inexact, we may reject some not-overflowing values incorrectly, but
they'll be on the order of exabytes allowed anyways.

This fixes divide error crash on x86 if bps_limit is not configured or
is set too high in the rare case that jiffy_elapsed is greater than HZ.

Fixes: e8368b57c0 ("blk-throttle: use calculate_io/bytes_allowed() for throtl_trim_slice()")
Fixes: 8d6bbaada2 ("blk-throttle: prevent overflow while calculating wait time")
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20231020223617.2739774-1-khazhy@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-02 09:35:29 +01:00
Ming Lei
752ec2d93e block: fix use-after-free of q->q_usage_counter
commit d36a9ea5e7 upstream.

For blk-mq, queue release handler is usually called after
blk_mq_freeze_queue_wait() returns. However, the
q_usage_counter->release() handler may not be run yet at that time, so
this can cause a use-after-free.

Fix the issue by moving percpu_ref_exit() into blk_free_queue_rcu().
Since ->release() is called with rcu read lock held, it is agreed that
the race should be covered in caller per discussion from the two links.

Reported-by: Zhang Wensheng <zhangwensheng@huaweicloud.com>
Reported-by: Zhong Jinghua <zhongjinghua@huawei.com>
Link: https://lore.kernel.org/linux-block/Y5prfOjyyjQKUrtH@T590/T/#u
Link: https://lore.kernel.org/lkml/Y4%2FmzMd4evRg9yDi@fedora/
Cc: Hillf Danton <hdanton@sina.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Cc: Dennis Zhou <dennis@kernel.org>
Fixes: 2b0d3d3e4f ("percpu_ref: reduce memory footprint of percpu_ref in fast path")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20221215021629.74870-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Saranya Muruganandam <saranyamohan@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-10 22:00:37 +02:00
Christoph Hellwig
00cf1dc13c block: factor out a bvec_set_page helper
[ Upstream commit d58cdfae6a ]

Add a helper to initialize a bvec based of a page pointer.  This will help
removing various open code bvec initializations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 1f0bbf2894 ("nvmet-tcp: pass iov_len instead of sg->length to bvec_set_page()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23 11:11:08 +02:00
Yu Kuai
84d5779234 blk-throttle: consider 'carryover_ios/bytes' in throtl_trim_slice()
[ Upstream commit eead005664 ]

Currently, 'carryover_ios/bytes' is not handled in throtl_trim_slice(),
for consequence, 'carryover_ios/bytes' will be used to throttle bio
multiple times, for example:

1) set iops limit to 100, and slice start is 0, slice end is 100ms;
2) current time is 0, and 10 ios are dispatched, those io won't be
   throttled and io_disp is 10;
3) still at current time 0, update iops limit to 1000, carryover_ios is
   updated to (0 - 10) = -10;
4) in this slice(0 - 100ms), io_allowed = 100 + (-10) = 90, which means
   only 90 ios can be dispatched without waiting;
5) assume that io is throttled in slice(0 - 100ms), and
   throtl_trim_slice() update silce to (100ms - 200ms). In this case,
   'carryover_ios/bytes' is not cleared and still only 90 ios can be
   dispatched between 100ms - 200ms.

Fix this problem by updating 'carryover_ios/bytes' in
throtl_trim_slice().

Fixes: a880ae93e5 ("blk-throttle: fix io hung due to configuration updates")
Reported-by: zhuxiaohui <zhuxiaohui.400@bytedance.com>
Link: https://lore.kernel.org/all/20230812072116.42321-1-zhuxiaohui.400@bytedance.com/
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230816012708.1193747-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-19 12:28:00 +02:00
Yu Kuai
fd2420905c blk-throttle: use calculate_io/bytes_allowed() for throtl_trim_slice()
[ Upstream commit e8368b57c0 ]

There are no functional changes, just make the code cleaner.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230816012708.1193747-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: eead005664 ("blk-throttle: consider 'carryover_ios/bytes' in throtl_trim_slice()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-19 12:28:00 +02:00
Li Lingfeng
5e4e9900e6 block: don't add or resize partition on the disk with GENHD_FL_NO_PART
commit 1a721de848 upstream.

Commit a33df75c63 ("block: use an xarray for disk->part_tbl") remove
disk_expand_part_tbl() in add_partition(), which means all kinds of
devices will support extended dynamic `dev_t`.
However, some devices with GENHD_FL_NO_PART are not expected to add or
resize partition.
Fix this by adding check of GENHD_FL_NO_PART before add or resize
partition.

Fixes: a33df75c63 ("block: use an xarray for disk->part_tbl")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230831075900.1725842-1-lilingfeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:43:02 +02:00
Zhiguo Niu
9183c4fe91 block/mq-deadline: use correct way to throttling write requests
[ Upstream commit d47f9717e5 ]

The original formula was inaccurate:
dd->async_depth = max(1UL, 3 * q->nr_requests / 4);

For write requests, when we assign a tags from sched_tags,
data->shallow_depth will be passed to sbitmap_find_bit,
see the following code:

nr = sbitmap_find_bit_in_word(&sb->map[index],
			min_t (unsigned int,
			__map_depth(sb, index),
			depth),
			alloc_hint, wrap);

The smaller of data->shallow_depth and __map_depth(sb, index)
will be used as the maximum range when allocating bits.

For a mmc device (one hw queue, deadline I/O scheduler):
q->nr_requests = sched_tags = 128, so according to the previous
calculation method, dd->async_depth = data->shallow_depth = 96,
and the platform is 64bits with 8 cpus, sched_tags.bitmap_tags.sb.shift=5,
sb.maps[]=32/32/32/32, 32 is smaller than 96, whether it is a read or
a write I/O, tags can be allocated to the maximum range each time,
which has not throttling effect.

In addition, refer to the methods of bfg/kyber I/O scheduler,
limit ratiois are calculated base on sched_tags.bitmap_tags.sb.shift.

This patch can throttle write requests really.

Fixes: 07757588e5 ("block/mq-deadline: Reserve 25% of scheduler tags for synchronous requests")

Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/1691061162-22898-1-git-send-email-zhiguo.niu@unisoc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:42:42 +02:00
Christoph Hellwig
00c0b2825b block: don't allow enabling a cache on devices that don't support it
[ Upstream commit 43c9835b14 ]

Currently the write_cache attribute allows enabling the QUEUE_FLAG_WC
flag on devices that never claimed the capability.

Fix that by adding a QUEUE_FLAG_HW_WC flag that is set by
blk_queue_write_cache and guards re-enabling the cache through sysfs.

Note that any rescan that calls blk_queue_write_cache will still
re-enable the write cache as in the current code.

Fixes: 93e9d8e836 ("block: add ability to flag write back caching on a device")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230707094239.107968-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:42:40 +02:00
Christoph Hellwig
e5e0ec8ff1 block: cleanup queue_wc_store
[ Upstream commit c4e21bcd0f ]

Get rid of the local queue_wc_store variable and handling setting and
clearing the QUEUE_FLAG_WC flag diretly instead the if / else if.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230707094239.107968-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 43c9835b14 ("block: don't allow enabling a cache on devices that don't support it")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:42:39 +02:00
Sweet Tea Dorminy
8ad3bfdd22 blk-crypto: dynamically allocate fallback profile
commit c984ff1423 upstream.

blk_crypto_profile_init() calls lockdep_register_key(), which warns and
does not register if the provided memory is a static object.
blk-crypto-fallback currently has a static blk_crypto_profile and calls
blk_crypto_profile_init() thereupon, resulting in the warning and
failure to register.

Fortunately it is simple enough to use a dynamically allocated profile
and make lockdep function correctly.

Fixes: 2fb48d88e7 ("blk-crypto: use dynamic lock class for blk_crypto_profile::lock")
Cc: stable@vger.kernel.org
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20230817141615.15387-1-sweettea-kernel@dorminy.me
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23 17:52:39 +02:00
Ross Lagerwall
557ea2ff05 blk-mq: Fix stall due to recursive flush plug
[ Upstream commit 7090426351 ]

We have seen rare IO stalls as follows:

* blk_mq_plug_issue_direct() is entered with an mq_list containing two
requests.
* For the first request, it sets last == false and enters the driver's
queue_rq callback.
* The driver queue_rq callback indirectly calls schedule() which calls
blk_flush_plug(). This may happen if the driver has the
BLK_MQ_F_BLOCKING flag set and is allowed to sleep in ->queue_rq.
* blk_flush_plug() handles the remaining request in the mq_list. mq_list
is now empty.
* The original call to queue_rq resumes (with last == false).
* The loop in blk_mq_plug_issue_direct() terminates because there are no
remaining requests in mq_list.

The IO is now stalled because the last request submitted to the driver
had last == false and there was no subsequent call to commit_rqs().

Fix this by returning early in blk_mq_flush_plug_list() if rq_count is 0
which it will be in the recursive case, rather than checking if the
mq_list is empty. At the same time, adjust one of the callers to skip
the mq_list empty check as it is not necessary.

Fixes: dc5fc361d8 ("block: attempt direct issue of plug list")
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230714101106.3635611-1-ross.lagerwall@citrix.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-03 10:23:48 +02:00
Eric Biggers
49f6ac6f1c blk-crypto: use dynamic lock class for blk_crypto_profile::lock
[ Upstream commit 2fb48d88e7 ]

When a device-mapper device is passing through the inline encryption
support of an underlying device, calls to blk_crypto_evict_key() take
the blk_crypto_profile::lock of the device-mapper device, then take the
blk_crypto_profile::lock of the underlying device (nested).  This isn't
a real deadlock, but it causes a lockdep report because there is only
one lock class for all instances of this lock.

Lockdep subclasses don't really work here because the hierarchy of block
devices is dynamic and could have more than 2 levels.

Instead, register a dynamic lock class for each blk_crypto_profile, and
associate that with the lock.

This avoids false-positive lockdep reports like the following:

    ============================================
    WARNING: possible recursive locking detected
    6.4.0-rc5 #2 Not tainted
    --------------------------------------------
    fscryptctl/1421 is trying to acquire lock:
    ffffff80829ca418 (&profile->lock){++++}-{3:3}, at: __blk_crypto_evict_key+0x44/0x1c0

                   but task is already holding lock:
    ffffff8086b68ca8 (&profile->lock){++++}-{3:3}, at: __blk_crypto_evict_key+0xc8/0x1c0

                   other info that might help us debug this:
     Possible unsafe locking scenario:

           CPU0
           ----
      lock(&profile->lock);
      lock(&profile->lock);

                    *** DEADLOCK ***

     May be due to missing lock nesting notation

Fixes: 1b26283970 ("block: Keyslot Manager for Inline Encryption")
Reported-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230610061139.212085-1-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-23 13:49:21 +02:00