Commit Graph

1212 Commits

Author SHA1 Message Date
Christoph Hellwig
abfc426d1b block: pass a block_device to bio_clone_fast
Pass a block_device to bio_clone_fast and __bio_clone_fast and give
the functions more suitable names.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20220202160109.108149-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-04 07:43:18 -07:00
Christoph Hellwig
49add4966d block: pass a block_device and opf to bio_init
Pass the block_device that we plan to use this bio for and the
operation to bio_init to optimize the assignment.  A NULL block_device
can be passed, both for the passthrough case on a raw request_queue and
to temporarily avoid refactoring some nasty code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220124091107.642561-19-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Christoph Hellwig
609be10667 block: pass a block_device and opf to bio_alloc_bioset
Pass the block_device and operation that we plan to use this bio for to
bio_alloc_bioset to optimize the assigment.  NULL/0 can be passed, both
for the passthrough case on a raw request_queue and to temporarily avoid
refactoring some nasty code.

Also move the gfp_mask argument after the nr_vecs argument for a much
more logical calling convention matching what most of the kernel does.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220124091107.642561-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Linus Torvalds
c9193f48e9 for-5.17/drivers-2022-01-11
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Merge tag 'for-5.17/drivers-2022-01-11' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:

 - mtip32xx pci cleanups (Bjorn)

 - mtip32xx conversion to generic power management (Vaibhav)

 - rsxx pci powermanagement cleanups (Bjorn)

 - Remove the rsxx driver. This hardware never saw much adoption, and
   it's been end of lifed for a while. (Christoph)

 - MD pull request from Song:
      - REQ_NOWAIT support (Vishal Verma)
      - raid6 benchmark optimization (Dirk Müller)
      - Fix for acct bioset (Xiao Ni)
      - Clean up max_queued_requests (Mariusz Tkaczyk)
      - PREEMPT_RT optimization (Davidlohr Bueso)
      - Use default_groups in kobj_type (Greg Kroah-Hartman)

 - Use attribute groups in pktcdvd and rnbd (Greg)

 - NVMe pull request from Christoph:
      - increment request genctr on completion (Keith Busch, Geliang
        Tang)
      - add a 'iopolicy' module parameter (Hannes Reinecke)
      - print out valid arguments when reading from /dev/nvme-fabrics
        (Hannes Reinecke)

 - Use struct_group() in drbd (Kees)

 - null_blk fixes (Ming)

 - Get rid of congestion logic in pktcdvd (Neil)

 - Floppy ejection hang fix (Tasos)

 - Floppy max user request size fix (Xiongwei)

 - Loop locking fix (Tetsuo)

* tag 'for-5.17/drivers-2022-01-11' of git://git.kernel.dk/linux-block: (32 commits)
  md: use default_groups in kobj_type
  md: Move alloc/free acct bioset in to personality
  lib/raid6: Use strict priority ranking for pq gen() benchmarking
  lib/raid6: skip benchmark of non-chosen xor_syndrome functions
  md: fix spelling of "its"
  md: raid456 add nowait support
  md: raid10 add nowait support
  md: raid1 add nowait support
  md: add support for REQ_NOWAIT
  md: drop queue limitation for RAID1 and RAID10
  md/raid5: play nice with PREEMPT_RT
  block/rnbd-clt-sysfs: use default_groups in kobj_type
  pktcdvd: convert to use attribute groups
  block: null_blk: only set set->nr_maps as 3 if active poll_queues is > 0
  nvme: add 'iopolicy' module parameter
  nvme: drop unused variable ctrl in nvme_setup_cmd
  nvme: increment request genctr on completion
  nvme-fabrics: print out valid arguments when reading from /dev/nvme-fabrics
  block: remove the rsxx driver
  rsxx: Drop PCI legacy power management
  ...
2022-01-12 10:35:23 -08:00
Linus Torvalds
d3c8108035 for-5.17/block-2022-01-11
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Merge tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - Unify where the struct request handling code is located in the blk-mq
   code (Christoph)

 - Header cleanups (Christoph)

 - Clean up the io_context handling code (Christoph, me)

 - Get rid of ->rq_disk in struct request (Christoph)

 - Error handling fix for add_disk() (Christoph)

 - request allocation cleanusp (Christoph)

 - Documentation updates (Eric, Matthew)

 - Remove trivial crypto unregister helper (Eric)

 - Reduce shared tag overhead (John)

 - Reduce poll_stats memory overhead (me)

 - Known indirect function call for dio (me)

 - Use atomic references for struct request (me)

 - Support request list issue for block and NVMe (me)

 - Improve queue dispatch pinning (Ming)

 - Improve the direct list issue code (Keith)

 - BFQ improvements (Jan)

 - Direct completion helper and use it in mmc block (Sebastian)

 - Use raw spinlock for the blktrace code (Wander)

 - fsync error handling fix (Ye)

 - Various fixes and cleanups (Lukas, Randy, Yang, Tetsuo, Ming, me)

* tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-block: (132 commits)
  MAINTAINERS: add entries for block layer documentation
  docs: block: remove queue-sysfs.rst
  docs: sysfs-block: document virt_boundary_mask
  docs: sysfs-block: document stable_writes
  docs: sysfs-block: fill in missing documentation from queue-sysfs.rst
  docs: sysfs-block: add contact for nomerges
  docs: sysfs-block: sort alphabetically
  docs: sysfs-block: move to stable directory
  block: don't protect submit_bio_checks by q_usage_counter
  block: fix old-style declaration
  nvme-pci: fix queue_rqs list splitting
  block: introduce rq_list_move
  block: introduce rq_list_for_each_safe macro
  block: move rq_list macros to blk-mq.h
  block: drop needless assignment in set_task_ioprio()
  block: remove unnecessary trailing '\'
  bio.h: fix kernel-doc warnings
  block: check minor range in device_add_disk()
  block: use "unsigned long" for blk_validate_block_size().
  block: fix error unwinding in device_add_disk
  ...
2022-01-12 10:26:52 -08:00
Greg Kroah-Hartman
1745e857e7 md: use default_groups in kobj_type
There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field.  Move the md rdev sysfs code to use default_groups field which
has been the preferred way since commit aa30f47cf6 ("kobject: Add
support for default attribute groups to kobj_type") so that we can soon
get rid of the obsolete default_attrs field.

Cc: Song Liu <song@kernel.org>
Cc: linux-raid@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Song Liu <song@kernel.org>
2022-01-06 10:42:50 -08:00
Xiao Ni
0c031fd37f md: Move alloc/free acct bioset in to personality
bioset acct is only needed for raid0 and raid5. Therefore, md_run only
allocates it for raid0 and raid5. However, this does not cover
personality takeover, which may cause uninitialized bioset. For example,
the following repro steps:

  mdadm -CR /dev/md0 -l1 -n2 /dev/loop0 /dev/loop1
  mdadm --wait /dev/md0
  mkfs.xfs /dev/md0
  mdadm /dev/md0 --grow -l5
  mount /dev/md0 /mnt

causes panic like:

[  225.933939] BUG: kernel NULL pointer dereference, address: 0000000000000000
[  225.934903] #PF: supervisor instruction fetch in kernel mode
[  225.935639] #PF: error_code(0x0010) - not-present page
[  225.936361] PGD 0 P4D 0
[  225.936677] Oops: 0010 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN PTI
[  225.937525] CPU: 27 PID: 1133 Comm: mount Not tainted 5.16.0-rc3+ #706
[  225.938416] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.module_el8.4.0+547+a85d02ba 04/01/2014
[  225.939922] RIP: 0010:0x0
[  225.940289] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[  225.941196] RSP: 0018:ffff88815897eff0 EFLAGS: 00010246
[  225.941897] RAX: 0000000000000000 RBX: 0000000000092800 RCX: ffffffff81370a39
[  225.942813] RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000092800
[  225.943772] RBP: 1ffff1102b12fe04 R08: fffffbfff0b43c01 R09: fffffbfff0b43c01
[  225.944807] R10: ffffffff85a1e007 R11: fffffbfff0b43c00 R12: ffff88810eaaaf58
[  225.945757] R13: 0000000000000000 R14: ffff88810eaaafb8 R15: ffff88815897f040
[  225.946709] FS:  00007ff3f2505080(0000) GS:ffff888fb5e00000(0000) knlGS:0000000000000000
[  225.947814] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  225.948556] CR2: ffffffffffffffd6 CR3: 000000015aa5a006 CR4: 0000000000370ee0
[  225.949537] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  225.950455] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  225.951414] Call Trace:
[  225.951787]  <TASK>
[  225.952120]  mempool_alloc+0xe5/0x250
[  225.952625]  ? mempool_resize+0x370/0x370
[  225.953187]  ? rcu_read_lock_sched_held+0xa1/0xd0
[  225.953862]  ? rcu_read_lock_bh_held+0xb0/0xb0
[  225.954464]  ? sched_clock_cpu+0x15/0x120
[  225.955019]  ? find_held_lock+0xac/0xd0
[  225.955564]  bio_alloc_bioset+0x1ed/0x2a0
[  225.956080]  ? lock_downgrade+0x3a0/0x3a0
[  225.956644]  ? bvec_alloc+0xc0/0xc0
[  225.957135]  bio_clone_fast+0x19/0x80
[  225.957651]  raid5_make_request+0x1370/0x1b70
[  225.958286]  ? sched_clock_cpu+0x15/0x120
[  225.958797]  ? __lock_acquire+0x8b2/0x3510
[  225.959339]  ? raid5_get_active_stripe+0xce0/0xce0
[  225.959986]  ? lock_is_held_type+0xd8/0x130
[  225.960528]  ? rcu_read_lock_sched_held+0xa1/0xd0
[  225.961135]  ? rcu_read_lock_bh_held+0xb0/0xb0
[  225.961703]  ? sched_clock_cpu+0x15/0x120
[  225.962232]  ? lock_release+0x27a/0x6c0
[  225.962746]  ? do_wait_intr_irq+0x130/0x130
[  225.963302]  ? lock_downgrade+0x3a0/0x3a0
[  225.963815]  ? lock_release+0x6c0/0x6c0
[  225.964348]  md_handle_request+0x342/0x530
[  225.964888]  ? set_in_sync+0x170/0x170
[  225.965397]  ? blk_queue_split+0x133/0x150
[  225.965988]  ? __blk_queue_split+0x8b0/0x8b0
[  225.966524]  ? submit_bio_checks+0x3b2/0x9d0
[  225.967069]  md_submit_bio+0x127/0x1c0
[...]

Fix this by moving alloc/free of acct bioset to pers->run and pers->free.

While we are on this, properly handle md_integrity_register() error in
raid0_run().

Fixes: daee202471 (md: check level before create and exit io_acct_set)
Cc: stable@vger.kernel.org
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
2022-01-06 08:37:03 -08:00
Randy Dunlap
dd3dc5f416 md: fix spelling of "its"
Use the possessive "its" instead of the contraction "it's"
in printed messages.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: linux-raid@vger.kernel.org
Signed-off-by: Song Liu <song@kernel.org>
2022-01-06 08:37:03 -08:00
Vishal Verma
f51d46d0e7 md: add support for REQ_NOWAIT
commit 021a24460d ("block: add QUEUE_FLAG_NOWAIT") added support
for checking whether a given bdev supports handling of REQ_NOWAIT or not.
Since then commit 6abc49468e ("dm: add support for REQ_NOWAIT and enable
it for linear target") added support for REQ_NOWAIT for dm. This uses
a similar approach to incorporate REQ_NOWAIT for md based bios.

This patch was tested using t/io_uring tool within FIO. A nvme drive
was partitioned into 2 partitions and a simple raid 0 configuration
/dev/md0 was created.

md0 : active raid0 nvme4n1p1[1] nvme4n1p2[0]
      937423872 blocks super 1.2 512k chunks

Before patch:

$ ./t/io_uring /dev/md0 -p 0 -a 0 -d 1 -r 100

Running top while the above runs:

$ ps -eL | grep $(pidof io_uring)

  38396   38396 pts/2    00:00:00 io_uring
  38396   38397 pts/2    00:00:15 io_uring
  38396   38398 pts/2    00:00:13 iou-wrk-38397

We can see iou-wrk-38397 io worker thread created which gets created
when io_uring sees that the underlying device (/dev/md0 in this case)
doesn't support nowait.

After patch:

$ ./t/io_uring /dev/md0 -p 0 -a 0 -d 1 -r 100

Running top while the above runs:

$ ps -eL | grep $(pidof io_uring)

  38341   38341 pts/2    00:10:22 io_uring
  38341   38342 pts/2    00:10:37 io_uring

After running this patch, we don't see any io worker thread
being created which indicated that io_uring saw that the
underlying device does support nowait. This is the exact behaviour
noticed on a dm device which also supports nowait.

For all the other raid personalities except raid0, we would need
to train pieces which involves make_request fn in order for them
to correctly handle REQ_NOWAIT.

Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Vishal Verma <vverma@digitalocean.com>
Signed-off-by: Song Liu <song@kernel.org>
2022-01-06 08:37:02 -08:00
zhangyue
07641b5f32 md: fix double free of mddev->private in autorun_array()
In driver/md/md.c, if the function autorun_array() is called,
the problem of double free may occur.

In function autorun_array(), when the function do_md_run() returns an
error, the function do_md_stop() will be called.

The function do_md_run() called function md_run(), but in function
md_run(), the pointer mddev->private may be freed.

The function do_md_stop() called the function __md_stop(), but in
function __md_stop(), the pointer mddev->private also will be freed
without judging null.

At this time, the pointer mddev->private will be double free, so it
needs to be judged null or not.

Signed-off-by: zhangyue <zhangyue1@kylinos.cn>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-12-10 09:11:07 -08:00
Markus Hochholdinger
55df1ce0d4 md: fix update super 1.0 on rdev size change
The superblock of version 1.0 doesn't get moved to the new position on a
device size change. This leads to a rdev without a superblock on a known
position, the raid can't be re-assembled.

The line was removed by mistake and is re-added by this patch.

Fixes: d9c0fa509e ("md: fix max sectors calculation for super 1.0")
Cc: stable@vger.kernel.org
Signed-off-by: Markus Hochholdinger <markus@hochholdinger.net>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-12-10 09:11:07 -08:00
Christoph Hellwig
1ebe2e5f9d block: remove GENHD_FL_EXT_DEVT
All modern drivers can support extra partitions using the extended
dev_t.  In fact except for the ioctl method drivers never even see
partitions in normal operation.

So remove the GENHD_FL_EXT_DEVT and allow extra partitions for all
block devices that do support partitions, and require those that
do not support partitions to explicit disallow them using
GENHD_FL_NO_PART.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211122130625.1136848-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29 06:38:35 -07:00
Linus Torvalds
3f01727f75 for-5.16/bdev-size-2021-10-29
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Merge tag 'for-5.16/bdev-size-2021-10-29' of git://git.kernel.dk/linux-block

Pull bdev size cleanups from Jens Axboe:
 "Clean up the bdev size handling with new bdev_nr_bytes() helper"

* tag 'for-5.16/bdev-size-2021-10-29' of git://git.kernel.dk/linux-block: (34 commits)
  partitions/ibm: use bdev_nr_sectors instead of open coding it
  partitions/efi: use bdev_nr_bytes instead of open coding it
  block/ioctl: use bdev_nr_sectors and bdev_nr_bytes
  block: cache inode size in bdev
  udf: use sb_bdev_nr_blocks
  reiserfs: use sb_bdev_nr_blocks
  ntfs: use sb_bdev_nr_blocks
  jfs: use sb_bdev_nr_blocks
  ext4: use sb_bdev_nr_blocks
  block: add a sb_bdev_nr_blocks helper
  block: use bdev_nr_bytes instead of open coding it in blkdev_fallocate
  squashfs: use bdev_nr_bytes instead of open coding it
  reiserfs: use bdev_nr_bytes instead of open coding it
  pstore/blk: use bdev_nr_bytes instead of open coding it
  ntfs3: use bdev_nr_bytes instead of open coding it
  nilfs2: use bdev_nr_bytes instead of open coding it
  nfs/blocklayout: use bdev_nr_bytes instead of open coding it
  jfs: use bdev_nr_bytes instead of open coding it
  hfsplus: use bdev_nr_sectors instead of open coding it
  hfs: use bdev_nr_sectors instead of open coding it
  ...
2021-11-01 09:50:37 -07:00
Xiao Ni
8b9e2291e3 md: update superblock after changing rdev flags in state_store
When the in memory flag is changed, we need to persist the change in the
rdev superblock flags. This is needed for "writemostly" and "failfast".

Reviewed-by: Li Feng <fengli@smartx.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:35 -06:00
Guoqing Jiang
5467948604 md: remove unused argument from md_new_event
Actually, mddev is not used by md_new_event.

Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:33 -06:00
Christoph Hellwig
7ad1069166 md: properly unwind when failing to add the kobject in md_alloc
Add proper error handling to delete the gendisk when failing to add
the md kobject and clean up the error unwinding in general.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:23 -06:00
Christoph Hellwig
94f3cd7d83 md: extend disks_mutex coverage
disks_mutex is intended to serialize md_alloc.  Extended it to also cover
the kobject_uevent call and getting the sysfs dirent to help reducing
error handling complexity.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:21 -06:00
Christoph Hellwig
51238e7fbd md: add the bitmap group to the default groups for the md kobject
Replace the deprecated default_attrs with the default_groups mechanism,
and add the always visible bitmap group to the groups created add
kobject_add time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:19 -06:00
Luis Chamberlain
9be68dd7ac md: add error handling support for add_disk()
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

We just do the unwinding of what was not done before, and are
sure to unlock prior to bailing.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:50:10 -06:00
Christoph Hellwig
0fe80347fd md: use bdev_nr_sectors instead of open coding it
Use the proper helper to read the block device size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20211018101130.1838532-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:43:22 -06:00
Christoph Hellwig
3e08773c38 block: switch polling to be bio based
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.

Polling for the bio itself leads to a few advantages:

 - the cookie construction can made entirely private in blk-mq.c
 - the caller does not need to remember the request_queue and cookie
   separately and thus sidesteps their lifetime issues
 - keeping the device and the cookie inside the bio allows to trivially
   support polling BIOs remapping by stacking drivers
 - a lot of code to propagate the cookie back up the submission path can
   be removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:36 -06:00
Christoph Hellwig
fe45e630a1 block: move integrity handling out of <linux/blkdev.h>
Split the integrity/metadata handling definitions out into a new header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-17-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:02 -06:00
Christoph Hellwig
b81e0c2372 block: drop unused includes in <linux/genhd.h>
Drop various include not actually used in genhd.h itself, and
move the remaning includes closer together.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:02 -06:00
Christoph Hellwig
7df835a32a md: fix a lock order reversal in md_alloc
Commit b0140891a8 ("md: Fix race when creating a new md device.")
not only moved assigning mddev->gendisk before calling add_disk, which
fixes the races described in the commit log, but also added a
mddev->open_mutex critical section over add_disk and creation of the
md kobj.  Adding a kobject after add_disk is racy vs deleting the gendisk
right after adding it, but md already prevents against that by holding
a mddev->active reference.

On the other hand taking this lock added a lock order reversal with what
is not disk->open_mutex (used to be bdev->bd_mutex when the commit was
added) for partition devices, which need that lock for the internal open
for the partition scan, and a recent commit also takes it for
non-partitioned devices, leading to further lockdep splatter.

Fixes: b0140891a8 ("md: Fix race when creating a new md device.")
Fixes: d626338735 ("block: support delayed holder registration")
Reported-by: syzbot+fadc0aaf497e6a493b9f@syzkaller.appspotmail.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: syzbot+fadc0aaf497e6a493b9f@syzkaller.appspotmail.com
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-09-22 08:45:58 -07:00
Linus Torvalds
440462198d for-5.14/drivers-2021-06-29
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Merge tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Pretty calm round, mostly just NVMe and a bit of MD:

   - NVMe updates (via Christoph)
        - improve the APST configuration algorithm (Alexey Bogoslavsky)
        - look for StorageD3Enable on companion ACPI device
          (Mario Limonciello)
        - allow selecting the network interface for TCP connections
          (Martin Belanger)
        - misc cleanups (Amit Engel, Chaitanya Kulkarni, Colin Ian King,
          Christoph)
        - move the ACPI StorageD3 code to drivers/acpi/ and add quirks
          for certain AMD CPUs (Mario Limonciello)
        - zoned device support for nvmet (Chaitanya Kulkarni)
        - fix the rules for changing the serial number in nvmet
          (Noam Gottlieb)
        - various small fixes and cleanups (Dan Carpenter, JK Kim,
          Chaitanya Kulkarni, Hannes Reinecke, Wesley Sheng, Geert
          Uytterhoeven, Daniel Wagner)

   - MD updates (Via Song)
        - iostats rewrite (Guoqing Jiang)
        - raid5 lock contention optimization (Gal Ofri)

   - Fall through warning fix (Gustavo)

   - Misc fixes (Gustavo, Jiapeng)"

* tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block: (78 commits)
  nvmet: use NVMET_MAX_NAMESPACES to set nn value
  loop: Fix missing discard support when using LOOP_CONFIGURE
  nvme.h: add missing nvme_lba_range_type endianness annotations
  nvme: remove zeroout memset call for struct
  nvme-pci: remove zeroout memset call for struct
  nvmet: remove zeroout memset call for struct
  nvmet: add ZBD over ZNS backend support
  nvmet: add Command Set Identifier support
  nvmet: add nvmet_req_bio put helper for backends
  nvmet: add req cns error complete helper
  block: export blk_next_bio()
  nvmet: remove local variable
  nvmet: use nvme status value directly
  nvmet: use u32 type for the local variable nsid
  nvmet: use u32 for nvmet_subsys max_nsid
  nvmet: use req->cmd directly in file-ns fast path
  nvmet: use req->cmd directly in bdev-ns fast path
  nvmet: make ver stable once connection established
  nvmet: allow mn change if subsys not discovered
  nvmet: make sn stable once connection was established
  ...
2021-06-30 12:21:16 -07:00
Guoqing Jiang
de3ea66e9d md: add comments in md_integrity_register
Given it is not obvious for the error handling, let's try to add some
comments here to make it clear.

Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
2021-06-14 22:32:07 -07:00
Guoqing Jiang
daee202471 md: check level before create and exit io_acct_set
The bio_set (io_acct_set) is used by personalities to clone bio and
trace the timestamp of bio. Some personalities such as raid1/10 don't
need the bio_set, so add check to not create it unconditionally.

Also update the comment for md_account_bio to make it more clear.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
2021-06-14 22:32:07 -07:00
Rikard Falkeborn
c32dc04059 md: Constify attribute_group structs
The attribute_group structs are never modified, they're only passed to
sysfs_create_group() and sysfs_remove_group(). Make them const to allow
the compiler to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Song Liu <song@kernel.org>
2021-06-14 22:32:07 -07:00
Guoqing Jiang
10764815ff md: add io accounting for raid0 and raid5
We introduce a new bioset (io_acct_set) for raid0 and raid5 since they
don't own clone infrastructure to accounting io. And the bioset is added
to mddev instead of to raid0 and raid5 layer, because with this way, we
can put common functions to md.h and reuse them in raid0 and raid5.

Also struct md_io_acct is added accordingly which includes io start_time,
the origin bio and cloned bio. Then we can call bio_{start,end}_io_acct
to get related io status.

Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
2021-06-14 22:32:06 -07:00
Guoqing Jiang
ad3fc79880 md: revert io stats accounting
The commit 41d2d848e5 ("md: improve io stats accounting") could cause
double fault problem per the report [1], and also it is not correct to
change ->bi_end_io if md don't own it, so let's revert it.

And io stats accounting will be replemented in later commits.

[1]. https://lore.kernel.org/linux-raid/3bf04253-3fad-434a-63a7-20214e38cf26@gmail.com/T/#t

Fixes: 41d2d848e5 ("md: improve io stats accounting")
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
2021-06-14 22:32:06 -07:00
Christoph Hellwig
0f1d2e0643 md: convert to blk_alloc_disk/blk_cleanup_disk
Convert the md driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01 07:42:23 -06:00
Heming Zhao
f7c7a2f9a2 md-cluster: fix use-after-free issue when removing rdev
md_kick_rdev_from_array will remove rdev, so we should
use rdev_for_each_safe to search list.

How to trigger:

env: Two nodes on kvm-qemu x86_64 VMs (2C2G with 2 iscsi luns).

```
node2=192.168.0.3

for i in {1..20}; do
    echo ==== $i `date` ====;

    mdadm -Ss && ssh ${node2} "mdadm -Ss"
    wipefs -a /dev/sda /dev/sdb

    mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l 1 /dev/sda \
       /dev/sdb --assume-clean
    ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb"
    mdadm --wait /dev/md0
    ssh ${node2} "mdadm --wait /dev/md0"

    mdadm --manage /dev/md0 --fail /dev/sda --remove /dev/sda
    sleep 1
done
```

Crash stack:

```
stack segment: 0000 [#1] SMP
... ...
RIP: 0010:md_check_recovery+0x1e8/0x570 [md_mod]
... ...
RSP: 0018:ffffb149807a7d68 EFLAGS: 00010207
RAX: 0000000000000000 RBX: ffff9d494c180800 RCX: ffff9d490fc01e50
RDX: fffff047c0ed8308 RSI: 0000000000000246 RDI: 0000000000000246
RBP: 6b6b6b6b6b6b6b6b R08: ffff9d490fc01e40 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: ffff9d494c180818 R14: ffff9d493399ef38 R15: ffff9d4933a1d800
FS:  0000000000000000(0000) GS:ffff9d494f700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe68cab9010 CR3: 000000004c6be001 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 raid1d+0x5c/0xd40 [raid1]
 ? finish_task_switch+0x75/0x2a0
 ? lock_timer_base+0x67/0x80
 ? try_to_del_timer_sync+0x4d/0x80
 ? del_timer_sync+0x41/0x50
 ? schedule_timeout+0x254/0x2d0
 ? md_start_sync+0xe0/0xe0 [md_mod]
 ? md_thread+0x127/0x160 [md_mod]
 md_thread+0x127/0x160 [md_mod]
 ? wait_woken+0x80/0x80
 kthread+0x10d/0x130
 ? kthread_park+0xa0/0xa0
 ret_from_fork+0x1f/0x40
```

Fixes: dbb64f8635 ("md-cluster: Fix adding of new disk with new reload code")
Fixes: 659b254fa7 ("md-cluster: remove a disk asynchronously from cluster environment")
Cc: stable@vger.kernel.org
Reviewed-by: Gang He <ghe@suse.com>
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Song Liu <song@kernel.org>
2021-04-23 09:39:04 -07:00
Christoph Hellwig
0d809b3837 md: do not return existing mddevs from mddev_find_or_alloc
Instead of returning an existing mddev, just for it to be discarded
later directly return -EEXIST.  Rename the function to mddev_alloc now
that it doesn't find an existing mddev.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
2021-04-15 11:06:32 -07:00
Christoph Hellwig
d144fe6ff1 md: refactor mddev_find_or_alloc
Allocate the new mddev first speculatively, which greatly simplifies
the code flow.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
2021-04-15 11:06:32 -07:00
Christoph Hellwig
85c8c3c1f8 md: factor out a mddev_alloc_unit helper from mddev_find
Split out a self contained helper to find a free minor for the md
"unit" number.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
2021-04-15 11:06:32 -07:00
Christoph Hellwig
65aa97c4d2 md: split mddev_find
Split mddev_find into a simple mddev_find that just finds an existing
mddev by the unit number, and a more complicated mddev_find that deals
with find or allocating a mddev.

This turns out to fix this bug reported by Zhao Heming.

----------------------------- snip ------------------------------
commit d3374825ce ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.

*** env ***
kvm-qemu VM 2C1G with 2 iscsi luns
kernel should be non-preempt

*** script ***

about trigger 1 time with 10 tests

`1  node1="15sp3-mdcluster1"
2  node2="15sp3-mdcluster2"
3
4  mdadm -Ss
5  ssh ${node2} "mdadm -Ss"
6  wipefs -a /dev/sda /dev/sdb
7  mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda \
   /dev/sdb --assume-clean
8
9  for i in {1..100}; do
10    echo ==== $i ====;
11
12    echo "test  ...."
13    ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb"
14    sleep 1
15
16    echo "clean  ....."
17    ssh ${node2} "mdadm -Ss"
18 done
`
I use mdcluster env to trigger soft lockup, but it isn't mdcluster
speical bug. To stop md array in mdcluster env will do more jobs than
non-cluster array, which will leave enough time/gap to allow kernel to
run md_open.

*** stack ***

`ID: 2831   TASK: ffff8dd7223b5040  CPU: 0   COMMAND: "mdadm"
 #0 [ffffa15d00a13b90] __schedule at ffffffffb8f1935f
 #1 [ffffa15d00a13ba8] exact_lock at ffffffffb8a4a66d
 #2 [ffffa15d00a13bb0] kobj_lookup at ffffffffb8c62fe3
 #3 [ffffa15d00a13c28] __blkdev_get at ffffffffb89273b9
 #4 [ffffa15d00a13c98] blkdev_get at ffffffffb8927964
 #5 [ffffa15d00a13cb0] do_dentry_open at ffffffffb88dc4b4
 #6 [ffffa15d00a13ce0] path_openat at ffffffffb88f0ccc
 #7 [ffffa15d00a13db8] do_filp_open at ffffffffb88f32bb
 #8 [ffffa15d00a13ee0] do_sys_open at ffffffffb88ddc7d
 #9 [ffffa15d00a13f38] do_syscall_64 at ffffffffb86053cb ffffffffb900008c

or:
[  884.226509]  mddev_put+0x1c/0xe0 [md_mod]
[  884.226515]  md_open+0x3c/0xe0 [md_mod]
[  884.226518]  __blkdev_get+0x30d/0x710
[  884.226520]  ? bd_acquire+0xd0/0xd0
[  884.226522]  blkdev_get+0x14/0x30
[  884.226524]  do_dentry_open+0x204/0x3a0
[  884.226531]  path_openat+0x2fc/0x1520
[  884.226534]  ? seq_printf+0x4e/0x70
[  884.226536]  do_filp_open+0x9b/0x110
[  884.226542]  ? md_release+0x20/0x20 [md_mod]
[  884.226543]  ? seq_read+0x1d8/0x3e0
[  884.226545]  ? kmem_cache_alloc+0x18a/0x270
[  884.226547]  ? do_sys_open+0x1bd/0x260
[  884.226548]  do_sys_open+0x1bd/0x260
[  884.226551]  do_syscall_64+0x5b/0x1e0
[  884.226554]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
`
*** rootcause ***

"mdadm -A" (or other array assemble commands) will start a daemon "mdadm
--monitor" by default. When "mdadm -Ss" is running, the stop action will
wakeup "mdadm --monitor". The "--monitor" daemon will immediately get
info from /proc/mdstat. This time mddev in kernel still exist, so
/proc/mdstat still show md device, which makes "mdadm --monitor" to open
/dev/md0.

The previously "mdadm -Ss" is removing action, the "mdadm --monitor"
open action will trigger md_open which is creating action. Racing is
happening.

`<thread 1>: "mdadm -Ss"
md_release
  mddev_put deletes mddev from all_mddevs
  queue_work for mddev_delayed_delete
  at this time, "/dev/md0" is still available for opening

<thread 2>: "mdadm --monitor ..."
md_open
 + mddev_find can't find mddev of /dev/md0, and create a new mddev and
 |    return.
 + trigger "if (mddev->gendisk != bdev->bd_disk)" and return
      -ERESTARTSYS.
`
In non-preempt kernel, <thread 2> is occupying on current CPU. and
mddev_delayed_delete which was created in <thread 1> also can't be
schedule.

In preempt kernel, it can also trigger above racing. But kernel doesn't
allow one thread running on a CPU all the time. after <thread 2> running
some time, the later "mdadm -A" (refer above script line 13) will call
md_alloc to alloc a new gendisk for mddev. it will break md_open
statement "if (mddev->gendisk != bdev->bd_disk)" and return 0 to caller,
the soft lockup is broken.
------------------------------ snip ------------------------------

Cc: stable@vger.kernel.org
Fixes: d3374825ce ("md: make devices disappear when they are no longer needed.")
Reported-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
2021-04-07 22:41:26 -07:00
Christoph Hellwig
8b57251f9a md: factor out a mddev_find_locked helper from mddev_find
Factor out a self-contained helper to just lookup a mddev by the dev_t
"unit".

Cc: stable@vger.kernel.org
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
2021-04-07 22:41:26 -07:00
Zhao Heming
6a4db2a603 md: md_open returns -EBUSY when entering racing area
commit d3374825ce ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.

This patch changes md_open returning from -ERESTARTSYS to -EBUSY, which
will break the infinitely retry when md_open enter racing area.

This patch is partly fix soft lockup issue, full fix needs mddev_find
is split into two functions: mddev_find & mddev_find_or_alloc. And
md_open should call new mddev_find (it only does searching job).

For more detail, please refer with Christoph's "split mddev_find" patch
in later commits.

*** env ***
kvm-qemu VM 2C1G with 2 iscsi luns
kernel should be non-preempt

*** script ***

about trigger every time with below script

```
1  node1="mdcluster1"
2  node2="mdcluster2"
3
4  mdadm -Ss
5  ssh ${node2} "mdadm -Ss"
6  wipefs -a /dev/sda /dev/sdb
7  mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda \
   /dev/sdb --assume-clean
8
9  for i in {1..10}; do
10    echo ==== $i ====;
11
12    echo "test  ...."
13    ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb"
14    sleep 1
15
16    echo "clean  ....."
17    ssh ${node2} "mdadm -Ss"
18 done
```

I use mdcluster env to trigger soft lockup, but it isn't mdcluster
speical bug. To stop md array in mdcluster env will do more jobs than
non-cluster array, which will leave enough time/gap to allow kernel to
run md_open.

*** stack ***

```
[  884.226509]  mddev_put+0x1c/0xe0 [md_mod]
[  884.226515]  md_open+0x3c/0xe0 [md_mod]
[  884.226518]  __blkdev_get+0x30d/0x710
[  884.226520]  ? bd_acquire+0xd0/0xd0
[  884.226522]  blkdev_get+0x14/0x30
[  884.226524]  do_dentry_open+0x204/0x3a0
[  884.226531]  path_openat+0x2fc/0x1520
[  884.226534]  ? seq_printf+0x4e/0x70
[  884.226536]  do_filp_open+0x9b/0x110
[  884.226542]  ? md_release+0x20/0x20 [md_mod]
[  884.226543]  ? seq_read+0x1d8/0x3e0
[  884.226545]  ? kmem_cache_alloc+0x18a/0x270
[  884.226547]  ? do_sys_open+0x1bd/0x260
[  884.226548]  do_sys_open+0x1bd/0x260
[  884.226551]  do_syscall_64+0x5b/0x1e0
[  884.226554]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
```

*** rootcause ***

"mdadm -A" (or other array assemble commands) will start a daemon "mdadm
--monitor" by default. When "mdadm -Ss" is running, the stop action will
wakeup "mdadm --monitor". The "--monitor" daemon will immediately get
info from /proc/mdstat. This time mddev in kernel still exist, so
/proc/mdstat still show md device, which makes "mdadm --monitor" to open
/dev/md0.

The previously "mdadm -Ss" is removing action, the "mdadm --monitor"
open action will trigger md_open which is creating action. Racing is
happening.

```
<thread 1>: "mdadm -Ss"
md_release
  mddev_put deletes mddev from all_mddevs
  queue_work for mddev_delayed_delete
  at this time, "/dev/md0" is still available for opening

<thread 2>: "mdadm --monitor ..."
md_open
 + mddev_find can't find mddev of /dev/md0, and create a new mddev and
 |    return.
 + trigger "if (mddev->gendisk != bdev->bd_disk)" and return
      -ERESTARTSYS.
```

In non-preempt kernel, <thread 2> is occupying on current CPU. and
mddev_delayed_delete which was created in <thread 1> also can't be
schedule.

In preempt kernel, it can also trigger above racing. But kernel doesn't
allow one thread running on a CPU all the time. after <thread 2> running
some time, the later "mdadm -A" (refer above script line 13) will call
md_alloc to alloc a new gendisk for mddev. it will break md_open
statement "if (mddev->gendisk != bdev->bd_disk)" and return 0 to caller,
the soft lockup is broken.

Cc: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <song@kernel.org>
2021-04-07 22:41:26 -07:00
Jan Glauber
7abfabaf5f md: Fix missing unused status line of /proc/mdstat
Reading /proc/mdstat with a read buffer size that would not
fit the unused status line in the first read will skip this
line from the output.

So 'dd if=/proc/mdstat bs=64 2>/dev/null' will not print something
like: unused devices: <none>

Don't return NULL immediately in start() for v=2 but call
show() once to print the status line also for multiple reads.

Cc: stable@vger.kernel.org
Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code and interface")
Signed-off-by: Jan Glauber <jglauber@digitalocean.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-03-24 16:29:07 -07:00
Xiao Ni
cf78408f93 md: add md_submit_discard_bio() for submitting discard bio
Move these logic from raid0.c to md.c, so that we can also use it in
raid10.c.

Reviewed-by: Coly Li <colyli@suse.de>
Reviewed-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Tested-by: Adrian Huang <ahuang12@lenovo.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-03-24 16:29:06 -07:00
Christoph Hellwig
a42e0d70c5 md: use rdev_read_only in restart_array
Make the read-only check in restart_array identical to the other two
read-only checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-01 09:35:20 -07:00
Christoph Hellwig
d7a4783883 md: check for NULL ->meta_bdev before calling bdev_read_only
->meta_bdev is optional and not set for most arrays.  Add a
rdev_read_only helper that calls bdev_read_only for both devices
in a safe way.

Fixes: 6f0d9689b6 ("block: remove the NULL bdev check in bdev_read_only")
Reported-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-01 09:35:20 -07:00
Christoph Hellwig
6a59656968 md: remove md_bio_alloc_sync
md_bio_alloc_sync is never called with a NULL mddev, and ->sync_set is
initialized in md_run, so it always must be initialized as well.  Just
open code the remaining call to bio_alloc_bioset.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-27 09:51:48 -07:00
Christoph Hellwig
32637385b8 md: simplify sync_page_io
Use an on-stack bio and biovec for the single page synchronous I/O.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-27 09:51:48 -07:00
Christoph Hellwig
a78f18da66 md: remove bio_alloc_mddev
bio_alloc_mddev is never called with a NULL mddev, and ->bio_set is
initialized in md_run, so it always must be initialized as well.  Just
open code the remaining call to bio_alloc_bioset.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-27 09:51:48 -07:00
Christoph Hellwig
99dfc43ecb block: use ->bi_bdev for bio based I/O accounting
Rework the I/O accounting for bio based drivers to use ->bi_bdev.  This
means all drivers can now simply use bio_start_io_acct to start
accounting, and it will take partitions into account automatically.  To
end I/O account either bio_end_io_acct can be used if the driver never
remaps I/O to a different device, or bio_end_io_acct_remapped if the
driver did remap the I/O.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24 18:17:20 -07:00
Christoph Hellwig
309dca309f block: store a block_device pointer in struct bio
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device.  From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24 18:17:20 -07:00
Xiao Ni
dc5d17a3c3 md: Set prev_flush_start and flush_bio in an atomic way
One customer reports a crash problem which causes by flush request. It
triggers a warning before crash.

        /* new request after previous flush is completed */
        if (ktime_after(req_start, mddev->prev_flush_start)) {
                WARN_ON(mddev->flush_bio);
                mddev->flush_bio = bio;
                bio = NULL;
        }

The WARN_ON is triggered. We use spin lock to protect prev_flush_start and
flush_bio in md_flush_request. But there is no lock protection in
md_submit_flush_data. It can set flush_bio to NULL first because of
compiler reordering write instructions.

For example, flush bio1 sets flush bio to NULL first in
md_submit_flush_data. An interrupt or vmware causing an extended stall
happen between updating flush_bio and prev_flush_start. Because flush_bio
is NULL, flush bio2 can get the lock and submit to underlayer disks. Then
flush bio1 updates prev_flush_start after the interrupt or extended stall.

Then flush bio3 enters in md_flush_request. The start time req_start is
behind prev_flush_start. The flush_bio is not NULL(flush bio2 hasn't
finished). So it can trigger the WARN_ON now. Then it calls INIT_WORK
again. INIT_WORK() will re-initialize the list pointers in the
work_struct, which then can result in a corrupted work list and the
work_struct queued a second time. With the work list corrupted, it can
lead in invalid work items being used and cause a crash in
process_one_work.

We need to make sure only one flush bio can be handled at one same time.
So add spin lock in md_submit_flush_data to protect prev_flush_start and
flush_bio in an atomic way.

Reviewed-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2021-01-20 08:18:10 -08:00
Linus Torvalds
69f637c335 for-5.11/drivers-2020-12-14
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Merge tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Nothing major in here:

   - NVMe pull request from Christoph:
        - nvmet passthrough improvements (Chaitanya Kulkarni)
        - fcloop error injection support (James Smart)
        - read-only support for zoned namespaces without Zone Append
          (Javier González)
        - improve some error message (Minwoo Im)
        - reject I/O to offline fabrics namespaces (Victor Gladkov)
        - PCI queue allocation cleanups (Niklas Schnelle)
        - remove an unused allocation in nvmet (Amit Engel)
        - a Kconfig spelling fix (Colin Ian King)
        - nvme_req_qid simplication (Baolin Wang)

   - MD pull request from Song:
        - Fix race condition in md_ioctl() (Dae R. Jeong)
        - Initialize read_slot properly for raid10 (Kevin Vigor)
        - Code cleanup (Pankaj Gupta)
        - md-cluster resync/reshape fix (Zhao Heming)

   - Move null_blk into its own directory (Damien Le Moal)

   - null_blk zone and discard improvements (Damien Le Moal)

   - bcache race fix (Dongsheng Yang)

   - Set of rnbd fixes/improvements (Gioh Kim, Guoqing Jiang, Jack Wang,
     Lutz Pogrell, Md Haris Iqbal)

   - lightnvm NULL pointer deref fix (tangzhenhao)

   - sr in_interrupt() removal (Sebastian Andrzej Siewior)

   - FC endpoint security support for s390/dasd (Jan Höppner, Sebastian
     Ott, Vineeth Vijayan). From the s390 arch guys, arch bits included
     as it made it easier for them to funnel the feature through the
     block driver tree.

   - Follow up fixes (Colin Ian King)"

* tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block: (64 commits)
  block: drop dead assignments in loop_init()
  sr: Remove in_interrupt() usage in sr_init_command().
  sr: Switch the sector size back to 2048 if sr_read_sector() changed it.
  cdrom: Reset sector_size back it is not 2048.
  drivers/lightnvm: fix a null-ptr-deref bug in pblk-core.c
  null_blk: Move driver into its own directory
  null_blk: Allow controlling max_hw_sectors limit
  null_blk: discard zones on reset
  null_blk: cleanup discard handling
  null_blk: Improve implicit zone close
  null_blk: improve zone locking
  block: Align max_hw_sectors to logical blocksize
  null_blk: Fail zone append to conventional zones
  null_blk: Fix zone size initialization
  bcache: fix race between setting bdev state to none and new write request direct to backing
  block/rnbd: fix a null pointer dereference on dev->blk_symlink_name
  block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
  block/rnbd: call kobject_put in the failure path
  Documentation/ABI/rnbd-srv: add document for force_close
  block/rnbd-srv: close a mapped device from server side.
  ...
2020-12-16 13:09:32 -08:00
Linus Torvalds
ac7ac4618c for-5.11/block-2020-12-14
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Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Another series of killing more code than what is being added, again
  thanks to Christoph's relentless cleanups and tech debt tackling.

  This contains:

   - blk-iocost improvements (Baolin Wang)

   - part0 iostat fix (Jeffle Xu)

   - Disable iopoll for split bios (Jeffle Xu)

   - block tracepoint cleanups (Christoph Hellwig)

   - Merging of struct block_device and hd_struct (Christoph Hellwig)

   - Rework/cleanup of how block device sizes are updated (Christoph
     Hellwig)

   - Simplification of gendisk lookup and removal of block device
     aliasing (Christoph Hellwig)

   - Block device ioctl cleanups (Christoph Hellwig)

   - Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig)

   - Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig)

   - sbitmap improvements (Pavel Begunkov)

   - Hybrid polling fix (Pavel Begunkov)

   - bvec iteration improvements (Pavel Begunkov)

   - Zone revalidation fixes (Damien Le Moal)

   - blk-throttle limit fix (Yu Kuai)

   - Various little fixes"

* tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits)
  blk-mq: fix msec comment from micro to milli seconds
  blk-mq: update arg in comment of blk_mq_map_queue
  blk-mq: add helper allocating tagset->tags
  Revert "block: Fix a lockdep complaint triggered by request queue flushing"
  nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class
  blk-mq: add new API of blk_mq_hctx_set_fq_lock_class
  block: disable iopoll for split bio
  block: Improve blk_revalidate_disk_zones() checks
  sbitmap: simplify wrap check
  sbitmap: replace CAS with atomic and
  sbitmap: remove swap_lock
  sbitmap: optimise sbitmap_deferred_clear()
  blk-mq: skip hybrid polling if iopoll doesn't spin
  blk-iocost: Factor out the base vrate change into a separate function
  blk-iocost: Factor out the active iocgs' state check into a separate function
  blk-iocost: Move the usage ratio calculation to the correct place
  blk-iocost: Remove unnecessary advance declaration
  blk-iocost: Fix some typos in comments
  blktrace: fix up a kerneldoc comment
  block: remove the request_queue to argument request based tracepoints
  ...
2020-12-16 12:57:51 -08:00