Commit Graph

469 Commits

Author SHA1 Message Date
Linus Torvalds
e0fc99e21e Merge tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:

 - NVMe:
      - ZNS support (Aravind, Keith, Matias, Niklas)
      - Misc cleanups, optimizations, fixes (Baolin, Chaitanya, David,
        Dongli, Max, Sagi)

 - null_blk zone capacity support (Aravind)

 - MD:
      - raid5/6 fixes (ChangSyun)
      - Warning fixes (Damien)
      - raid5 stripe fixes (Guoqing, Song, Yufen)
      - sysfs deadlock fix (Junxiao)
      - raid10 deadlock fix (Vitaly)

 - struct_size conversions (Gustavo)

 - Set of bcache updates/fixes (Coly)

* tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block: (117 commits)
  md/raid5: Allow degraded raid6 to do rmw
  md/raid5: Fix Force reconstruct-write io stuck in degraded raid5
  raid5: don't duplicate code for different paths in handle_stripe
  raid5-cache: hold spinlock instead of mutex in r5c_journal_mode_show
  md: print errno in super_written
  md/raid5: remove the redundant setting of STRIPE_HANDLE
  md: register new md sysfs file 'uuid' read-only
  md: fix max sectors calculation for super 1.0
  nvme-loop: remove extra variable in create ctrl
  nvme-loop: set ctrl state connecting after init
  nvme-multipath: do not fall back to __nvme_find_path() for non-optimized paths
  nvme-multipath: fix logic for non-optimized paths
  nvme-rdma: fix controller reset hang during traffic
  nvme-tcp: fix controller reset hang during traffic
  nvmet: introduce the passthru Kconfig option
  nvmet: introduce the passthru configfs interface
  nvmet: Add passthru enable/disable helpers
  nvmet: add passthru code to process commands
  nvme: export nvme_find_get_ns() and nvme_put_ns()
  nvme: introduce nvme_ctrl_get_by_path()
  ...
2020-08-05 10:51:40 -07:00
Vitaly Mayatskikh
fe630de009 md/raid10: avoid deadlock on recovery.
When disk failure happens and the array has a spare drive, resync thread
kicks in and starts to refill the spare. However it may get blocked by
a retry thread that resubmits failed IO to a mirror and itself can get
blocked on a barrier raised by the resync thread.

Acked-by: Nigel Croxon <ncroxon@redhat.com>
Signed-off-by: Vitaly Mayatskikh <vmayatskikh@digitalocean.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-07-22 11:44:54 -07:00
Damien Le Moal
38ffc01f38 md: raid10: Fix compilation warning
Remove the if statement around the call to sysfs_link_rdev() in
raid10_start_reshape() to avoid the compilation warning:

warning: suggest braces around empty body in an ‘if’ statement

when compiling with W=1.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-07-15 22:46:07 -07:00
Junxiao Bi
e1a86dbbbd md: fix deadlock causing by sysfs_notify
The following deadlock was captured. The first process is holding 'kernfs_mutex'
and hung by io. The io was staging in 'r1conf.pending_bio_list' of raid1 device,
this pending bio list would be flushed by second process 'md127_raid1', but
it was hung by 'kernfs_mutex'. Using sysfs_notify_dirent_safe() to replace
sysfs_notify() can fix it. There were other sysfs_notify() invoked from io
path, removed all of them.

 PID: 40430  TASK: ffff8ee9c8c65c40  CPU: 29  COMMAND: "probe_file"
  #0 [ffffb87c4df37260] __schedule at ffffffff9a8678ec
  #1 [ffffb87c4df372f8] schedule at ffffffff9a867f06
  #2 [ffffb87c4df37310] io_schedule at ffffffff9a0c73e6
  #3 [ffffb87c4df37328] __dta___xfs_iunpin_wait_3443 at ffffffffc03a4057 [xfs]
  #4 [ffffb87c4df373a0] xfs_iunpin_wait at ffffffffc03a6c79 [xfs]
  #5 [ffffb87c4df373b0] __dta_xfs_reclaim_inode_3357 at ffffffffc039a46c [xfs]
  #6 [ffffb87c4df37400] xfs_reclaim_inodes_ag at ffffffffc039a8b6 [xfs]
  #7 [ffffb87c4df37590] xfs_reclaim_inodes_nr at ffffffffc039bb33 [xfs]
  #8 [ffffb87c4df375b0] xfs_fs_free_cached_objects at ffffffffc03af0e9 [xfs]
  #9 [ffffb87c4df375c0] super_cache_scan at ffffffff9a287ec7
 #10 [ffffb87c4df37618] shrink_slab at ffffffff9a1efd93
 #11 [ffffb87c4df37700] shrink_node at ffffffff9a1f5968
 #12 [ffffb87c4df37788] do_try_to_free_pages at ffffffff9a1f5ea2
 #13 [ffffb87c4df377f0] try_to_free_mem_cgroup_pages at ffffffff9a1f6445
 #14 [ffffb87c4df37880] try_charge at ffffffff9a26cc5f
 #15 [ffffb87c4df37920] memcg_kmem_charge_memcg at ffffffff9a270f6a
 #16 [ffffb87c4df37958] new_slab at ffffffff9a251430
 #17 [ffffb87c4df379c0] ___slab_alloc at ffffffff9a251c85
 #18 [ffffb87c4df37a80] __slab_alloc at ffffffff9a25635d
 #19 [ffffb87c4df37ac0] kmem_cache_alloc at ffffffff9a251f89
 #20 [ffffb87c4df37b00] alloc_inode at ffffffff9a2a2b10
 #21 [ffffb87c4df37b20] iget_locked at ffffffff9a2a4854
 #22 [ffffb87c4df37b60] kernfs_get_inode at ffffffff9a311377
 #23 [ffffb87c4df37b80] kernfs_iop_lookup at ffffffff9a311e2b
 #24 [ffffb87c4df37ba8] lookup_slow at ffffffff9a290118
 #25 [ffffb87c4df37c10] walk_component at ffffffff9a291e83
 #26 [ffffb87c4df37c78] path_lookupat at ffffffff9a293619
 #27 [ffffb87c4df37cd8] filename_lookup at ffffffff9a2953af
 #28 [ffffb87c4df37de8] user_path_at_empty at ffffffff9a295566
 #29 [ffffb87c4df37e10] vfs_statx at ffffffff9a289787
 #30 [ffffb87c4df37e70] SYSC_newlstat at ffffffff9a289d5d
 #31 [ffffb87c4df37f18] sys_newlstat at ffffffff9a28a60e
 #32 [ffffb87c4df37f28] do_syscall_64 at ffffffff9a003949
 #33 [ffffb87c4df37f50] entry_SYSCALL_64_after_hwframe at ffffffff9aa001ad
     RIP: 00007f617a5f2905  RSP: 00007f607334f838  RFLAGS: 00000246
     RAX: ffffffffffffffda  RBX: 00007f6064044b20  RCX: 00007f617a5f2905
     RDX: 00007f6064044b20  RSI: 00007f6064044b20  RDI: 00007f6064005890
     RBP: 00007f6064044aa0   R8: 0000000000000030   R9: 000000000000011c
     R10: 0000000000000013  R11: 0000000000000246  R12: 00007f606417e6d0
     R13: 00007f6064044aa0  R14: 00007f6064044b10  R15: 00000000ffffffff
     ORIG_RAX: 0000000000000006  CS: 0033  SS: 002b

 PID: 927    TASK: ffff8f15ac5dbd80  CPU: 42  COMMAND: "md127_raid1"
  #0 [ffffb87c4df07b28] __schedule at ffffffff9a8678ec
  #1 [ffffb87c4df07bc0] schedule at ffffffff9a867f06
  #2 [ffffb87c4df07bd8] schedule_preempt_disabled at ffffffff9a86825e
  #3 [ffffb87c4df07be8] __mutex_lock at ffffffff9a869bcc
  #4 [ffffb87c4df07ca0] __mutex_lock_slowpath at ffffffff9a86a013
  #5 [ffffb87c4df07cb0] mutex_lock at ffffffff9a86a04f
  #6 [ffffb87c4df07cc8] kernfs_find_and_get_ns at ffffffff9a311d83
  #7 [ffffb87c4df07cf0] sysfs_notify at ffffffff9a314b3a
  #8 [ffffb87c4df07d18] md_update_sb at ffffffff9a688696
  #9 [ffffb87c4df07d98] md_update_sb at ffffffff9a6886d5
 #10 [ffffb87c4df07da8] md_check_recovery at ffffffff9a68ad9c
 #11 [ffffb87c4df07dd0] raid1d at ffffffffc01f0375 [raid1]
 #12 [ffffb87c4df07ea0] md_thread at ffffffff9a680348
 #13 [ffffb87c4df07f08] kthread at ffffffff9a0b8005
 #14 [ffffb87c4df07f50] ret_from_fork at ffffffff9aa00344

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-07-14 22:58:51 -07:00
Christoph Hellwig
21cf866145 writeback: remove bdi->congested_fn
Except for pktdvd, the only places setting congested bits are file
systems that allocate their own backing_dev_info structures.  And
pktdvd is a deprecated driver that isn't useful in stack setup
either.  So remove the dead congested_fn stacking infrastructure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>
[axboe: fixup unused variables in bcache/request.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 17:20:46 -06:00
Christoph Hellwig
ed00aabd5e block: rename generic_make_request to submit_bio_noacct
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:24 -06:00
John Pittman
45422b704d md/raid10: prevent access of uninitialized resync_pages offset
Due to unneeded multiplication in the out_free_pages portion of
r10buf_pool_alloc(), when using a 3-copy raid10 layout, it is
possible to access a resync_pages offset that has not been
initialized.  This access translates into a crash of the system
within resync_free_pages() while passing a bad pointer to
put_page().  Remove the multiplication, preventing access to the
uninitialized area.

Fixes: f025061836 ("md: raid10: don't use bio's vec table to manage resync pages")
Cc: stable@vger.kernel.org # 4.12+
Signed-off-by: John Pittman <jpittman@redhat.com>
Suggested-by: David Jeffery <djeffery@redhat.com>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-11-11 16:47:39 -08:00
David Jeffery
775d78319f md: improve handling of bio with REQ_PREFLUSH in md_flush_request()
If pers->make_request fails in md_flush_request(), the bio is lost. To
fix this, pass back a bool to indicate if the original make_request call
should continue to handle the I/O and instead of assuming the flush logic
will push it to completion.

Convert md_flush_request to return a bool and no longer calls the raid
driver's make_request function.  If the return is true, then the md flush
logic has or will complete the bio and the md make_request call is done.
If false, then the md make_request function needs to keep processing like
it is a normal bio. Let the original call to md_handle_request handle any
need to retry sending the bio to the raid driver's make_request function
should it be needed.

Also mark md_flush_request and the make_request function pointer as
__must_check to issue warnings should these critical return values be
ignored.

Fixes: 2bc13b83e6 ("md: batch flush requests.")
Cc: stable@vger.kernel.org # # v4.19+
Cc: NeilBrown <neilb@suse.com>
Signed-off-by: David Jeffery <djeffery@redhat.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-10-24 15:22:40 -07:00
Guoqing Jiang
9a567843f7 md: allow last device to be forcibly removed from RAID1/RAID10.
When the 'last' device in a RAID1 or RAID10 reports an error,
we do not mark it as failed.  This would serve little purpose
as there is no risk of losing data beyond that which is obviously
lost (as there is with RAID5), and there could be other sectors
on the device which are readable, and only readable from this device.
This in general this maximises access to data.

However the current implementation also stops an admin from removing
the last device by direct action.  This is rarely useful, but in many
case is not harmful and can make automation easier by removing special
cases.

Also, if an attempt to write metadata fails the device must be marked
as faulty, else an infinite loop will result, attempting to update
the metadata on all non-faulty devices.

So add 'fail_last_dev' member to 'struct mddev', then we can bypasses
the 'last disk' checks for RAID1 and RAID10, and control the behavior
per array by change sysfs node.

Signed-off-by: NeilBrown <neilb@suse.de>
[add sysfs node for fail_last_dev by Guoqing]
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-08-07 10:25:02 -07:00
Yufen Yu
7cee6d4e60 md/raid10: end bio when the device faulty
Just like raid1, we do not queue write error bio to retry write
and acknowlege badblocks, when the device is faulty.

Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-08-07 10:25:02 -07:00
Guoqing Jiang
e9eeba28a1 md/raid10: read balance chooses idlest disk for SSD
Andy reported that raid10 array with SSD disks has poor
read performance. Compared with raid1, RAID-1 can be 3x
faster than RAID-10 sometimes [1].

The thing is that raid10 chooses the low distance disk
for read request, however, the approach doesn't work
well for SSD device since it doesn't have spindle like
HDD, we should just read from the SSD which has less
pending IO like commit 9dedf60313 ("md/raid1: read
balance chooses idlest disk for SSD").

So this commit selects the idlest SSD disk for read if
array has none rotational disk, otherwise, read_balance
uses the previous distance priority algorithm. With the
change, the performance of raid10 gets increased largely
per Andy's test [2].

[1]. https://marc.info/?l=linux-raid&m=155915890004761&w=2
[2]. https://marc.info/?l=linux-raid&m=155990654223786&w=2

Tested-by: Andy Smith <andy@strugglers.net>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-15 01:37:35 -06:00
Marcos Paulo de Souza
c7afa8034b md: raid1-10: Unify r{1,10}bio_pool_free
Avoiding duplicated code, since they just execute a kfree.

Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-15 01:37:35 -06:00
Gustavo A. R. Silva
8cf05a7841 md: raid10: Use struct_size() in kmalloc()
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
   int stuff;
   struct boo entry[];
};

instance = kmalloc(size, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-15 01:37:34 -06:00
Marcos Paulo de Souza
3f677f9c99 drivers: md: Unify common definitions of raid1 and raid10
These definitions are being moved to raid1-10.c.

Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-15 01:37:34 -06:00
Thomas Gleixner
af1a8899d2 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 or at your option any
  later version you should have received a copy of the gnu general
  public license for example usr src linux copying if not write to the
  free software foundation inc 675 mass ave cambridge ma 02139 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 20 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.552543146@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:13 +02:00
Aditya Pakki
e406f12dde md: Fix failed allocation of md_register_thread
mddev->sync_thread can be set to NULL on kzalloc failure downstream.
The patch checks for such a scenario and frees allocated resources.

Committer node:

Added similar fix to raid5.c, as suggested by Guoqing.

Cc: stable@vger.kernel.org # v3.16+
Acked-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-03-12 10:15:18 -07:00
Xiao Ni
b761dcf121 It's wrong to add len to sector_nr in raid10 reshape twice
In reshape_request it already adds len to sector_nr already. It's wrong to add len to
sector_nr again after adding pages to bio. If there is bad block it can't copy one chunk
at a time, it needs to goto read_more. Now the sector_nr is wrong. It can cause data
corruption.

Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-03-12 10:15:18 -07:00
Guoqing Jiang
e820d55cb9 md: fix raid10 hang issue caused by barrier
When both regular IO and resync IO happen at the same time,
and if we also need to split regular. Then we can see tasks
hang due to barrier.

1. resync thread
[ 1463.757205] INFO: task md1_resync:5215 blocked for more than 480 seconds.
[ 1463.757207]       Not tainted 4.19.5-1-default #1
[ 1463.757209] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1463.757212] md1_resync      D    0  5215      2 0x80000000
[ 1463.757216] Call Trace:
[ 1463.757223]  ? __schedule+0x29a/0x880
[ 1463.757231]  ? raise_barrier+0x8d/0x140 [raid10]
[ 1463.757236]  schedule+0x78/0x110
[ 1463.757243]  raise_barrier+0x8d/0x140 [raid10]
[ 1463.757248]  ? wait_woken+0x80/0x80
[ 1463.757257]  raid10_sync_request+0x1f6/0x1e30 [raid10]
[ 1463.757265]  ? _raw_spin_unlock_irq+0x22/0x40
[ 1463.757284]  ? is_mddev_idle+0x125/0x137 [md_mod]
[ 1463.757302]  md_do_sync.cold.78+0x404/0x969 [md_mod]
[ 1463.757311]  ? wait_woken+0x80/0x80
[ 1463.757336]  ? md_rdev_init+0xb0/0xb0 [md_mod]
[ 1463.757351]  md_thread+0xe9/0x140 [md_mod]
[ 1463.757358]  ? _raw_spin_unlock_irqrestore+0x2e/0x60
[ 1463.757364]  ? __kthread_parkme+0x4c/0x70
[ 1463.757369]  kthread+0x112/0x130
[ 1463.757374]  ? kthread_create_worker_on_cpu+0x40/0x40
[ 1463.757380]  ret_from_fork+0x3a/0x50

2. regular IO
[ 1463.760679] INFO: task kworker/0:8:5367 blocked for more than 480 seconds.
[ 1463.760683]       Not tainted 4.19.5-1-default #1
[ 1463.760684] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1463.760687] kworker/0:8     D    0  5367      2 0x80000000
[ 1463.760718] Workqueue: md submit_flushes [md_mod]
[ 1463.760721] Call Trace:
[ 1463.760731]  ? __schedule+0x29a/0x880
[ 1463.760741]  ? wait_barrier+0xdd/0x170 [raid10]
[ 1463.760746]  schedule+0x78/0x110
[ 1463.760753]  wait_barrier+0xdd/0x170 [raid10]
[ 1463.760761]  ? wait_woken+0x80/0x80
[ 1463.760768]  raid10_write_request+0xf2/0x900 [raid10]
[ 1463.760774]  ? wait_woken+0x80/0x80
[ 1463.760778]  ? mempool_alloc+0x55/0x160
[ 1463.760795]  ? md_write_start+0xa9/0x270 [md_mod]
[ 1463.760801]  ? try_to_wake_up+0x44/0x470
[ 1463.760810]  raid10_make_request+0xc1/0x120 [raid10]
[ 1463.760816]  ? wait_woken+0x80/0x80
[ 1463.760831]  md_handle_request+0x121/0x190 [md_mod]
[ 1463.760851]  md_make_request+0x78/0x190 [md_mod]
[ 1463.760860]  generic_make_request+0x1c6/0x470
[ 1463.760870]  raid10_write_request+0x77a/0x900 [raid10]
[ 1463.760875]  ? wait_woken+0x80/0x80
[ 1463.760879]  ? mempool_alloc+0x55/0x160
[ 1463.760895]  ? md_write_start+0xa9/0x270 [md_mod]
[ 1463.760904]  raid10_make_request+0xc1/0x120 [raid10]
[ 1463.760910]  ? wait_woken+0x80/0x80
[ 1463.760926]  md_handle_request+0x121/0x190 [md_mod]
[ 1463.760931]  ? _raw_spin_unlock_irq+0x22/0x40
[ 1463.760936]  ? finish_task_switch+0x74/0x260
[ 1463.760954]  submit_flushes+0x21/0x40 [md_mod]

So resync io is waiting for regular write io to complete to
decrease nr_pending (conf->barrier++ is called before waiting).
The regular write io splits another bio after call wait_barrier
which call nr_pending++, then the splitted bio would continue
with raid10_write_request -> wait_barrier, so the splitted bio
has to wait for barrier to be zero, then deadlock happens as
follows.

	resync io		regular io

	raise_barrier
				wait_barrier
				generic_make_request
				wait_barrier

To resolve the issue, we need to call allow_barrier to decrease
nr_pending before generic_make_request since regular IO is not
issued to underlying devices, and wait_barrier is called again
to ensure no internal IO happening.

Fixes: fc9977dd06 ("md/raid10: simplify the splitting of requests.")
Reported-and-tested-by: Siniša Bandin <sinisa@4net.rs>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-12-20 08:53:24 -08:00
Guoqing Jiang
caea3c47ad raid10: refactor common wait code from regular read/write request
Both raid10_read_request and raid10_write_request share
the same code at the beginning of them, so introduce
regular_request_wait to clean up code, and call it in
both request functions.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-12-20 08:53:24 -08:00
Guoqing Jiang
5ebaf80bc8 md-cluster: introduce resync_info_get interface for sanity check
Since the resync region from suspend_info means one node
is reshaping this area, so the position of reshape_progress
should be included in the area.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-10-18 09:36:35 -07:00
Guoqing Jiang
7564beda19 md-cluster/raid10: support add disk under grow mode
For clustered raid10 scenario, we need to let all the nodes
know about that a new disk is added to the array, and the
reshape caused by add new member just need to be happened in
one node, but other nodes should know about the change.

Since reshape means read data from somewhere (which is already
used by array) and write data to unused region. Obviously, it
is awful if one node is reading data from address while another
node is writing to the same address. Considering we have
implemented suspend writes in the resyncing area, so we can
just broadcast the reading address to other nodes to avoid the
trouble.

For master node, it would call reshape_request then update sb
during the reshape period. To avoid above trouble, we call
resync_info_update to send RESYNC message in reshape_request.

Then from slave node's view, it receives two type messages:
1. RESYNCING message
Slave node add the address (where master node reading data from)
to suspend list.

2. METADATA_UPDATED message
Once slave nodes know the reshaping is started in master node,
it is time to update reshape position and call start_reshape to
follow master node's step. After reshape is done, only reshape
position is need to be updated, so the majority task of reshaping
is happened on the master node.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-10-18 09:34:56 -07:00
Guoqing Jiang
afd7562860 md-cluster/raid10: resize all the bitmaps before start reshape
To support add disk under grow mode, we need to resize
all the bitmaps of each node before reshape, so that we
can ensure all nodes have the same view of the bitmap of
the clustered raid.

So after the master node resized the bitmap, it broadcast
a message to other slave nodes, and it checks the size of
each bitmap are same or not by compare pages. We can only
continue the reshaping after all nodes update the bitmap
to the same size (by checking the pages), otherwise revert
bitmap size to previous value.

The resize_bitmaps interface and BITMAP_RESIZE message are
introduced in md-cluster.c for the purpose.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-10-18 09:30:58 -07:00
Shaohua Li
9e753ba9b9 MD: fix invalid stored role for a disk - try2
Commit d595567dc4 (MD: fix invalid stored role for a disk) broke linear
hotadd. Let's only fix the role for disks in raid1/10.
Based on Guoqing's original patch.

Reported-by: kernel test robot <rong.a.chen@intel.com>
Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
Cc: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-10-14 17:05:07 -07:00
Alex Wu
ee37d7314a md/raid10: Fix raid10 replace hang when new added disk faulty
[Symptom]

Resync thread hang when new added disk faulty during replacing.

[Root Cause]

In raid10_sync_request(), we expect to issue a bio with callback
end_sync_read(), and a bio with callback end_sync_write().

In normal situation, we will add resyncing sectors into
mddev->recovery_active when raid10_sync_request() returned, and sub
resynced sectors from mddev->recovery_active when end_sync_write()
calls end_sync_request().

If new added disk, which are replacing the old disk, is set faulty,
there is a race condition:
    1. In the first rcu protected section, resync thread did not detect
       that mreplace is set faulty and pass the condition.
    2. In the second rcu protected section, mreplace is set faulty.
    3. But, resync thread will prepare the read object first, and then
       check the write condition.
    4. It will find that mreplace is set faulty and do not have to
       prepare write object.
This cause we add resync sectors but never sub it.

[How to Reproduce]

This issue can be easily reproduced by the following steps:
    mdadm -C /dev/md0 --assume-clean -l 10 -n 4 /dev/sd[abcd]
    mdadm /dev/md0 -a /dev/sde
    mdadm /dev/md0 --replace /dev/sdd
    sleep 1
    mdadm /dev/md0 -f /dev/sde

[How to Fix]

This issue can be fixed by using local variables to record the result
of test conditions. Once the conditions are satisfied, we can make sure
that we need to issue a bio for read and a bio for write.

Previous 'commit 24afd80d99 ("md/raid10: handle recovery of
replacement devices.")' will also check whether bio is NULL, but leave
the comment saying that it is a pointless test. So we remove this dummy
check.

Reported-by: Alex Chen <alexchen@synology.com>
Reviewed-by: Allen Peng <allenpeng@synology.com>
Reviewed-by: BingJing Chang <bingjingc@synology.com>
Signed-off-by: Alex Wu <alexwu@synology.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-09-28 11:42:47 -07:00
Xiao Ni
1d0ffd2642 RAID10 BUG_ON in raise_barrier when force is true and conf->barrier is 0
In raid10 reshape_request it gets max_sectors in read_balance. If the underlayer disks
have bad blocks, the max_sectors is less than last. It will call goto read_more many
times. It calls raise_barrier(conf, sectors_done != 0) every time. In this condition
sectors_done is not 0. So the value passed to the argument force of raise_barrier is
true.

In raise_barrier it checks conf->barrier when force is true. If force is true and
conf->barrier is 0, it panic. In this case reshape_request submits bio to under layer
disks. And in the callback function of the bio it calls lower_barrier. If the bio
finishes before calling raise_barrier again, it can trigger the BUG_ON.

Add one pair of raise_barrier/lower_barrier to fix this bug.

Signed-off-by: Xiao Ni <xni@redhat.com>
Suggested-by: Neil Brown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-08-31 17:38:10 -07:00