Commit Graph

116 Commits

Author SHA1 Message Date
Li Lingfeng
7eb8ff02c1 md: Hold mddev->reconfig_mutex when trying to get mddev->sync_thread
Commit ba9d9f1a707f ("Revert "md: unlock mddev before reap sync_thread in
action_store"") removed the scenario of calling md_unregister_thread()
without holding mddev->reconfig_mutex, so add a lock holding check before
acquiring mddev->sync_thread by passing mdev to md_unregister_thread().

Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20230803071711.2546560-1-lilingfeng@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
2023-08-15 09:40:26 -07:00
Yu Kuai
4469315439 md: protect md_thread with rcu
Currently, there are many places that md_thread can be accessed without
protection, following are known scenarios that can cause
null-ptr-dereference or uaf:

1) sync_thread that is allocated and started from md_start_sync()
2) mddev->thread can be accessed directly from timeout_store() and
   md_bitmap_daemon_work()
3) md_unregister_thread() from action_store().

Currently, a global spinlock 'pers_lock' is borrowed to protect
'mddev->thread' in some places, this problem can be fixed likewise,
however, use a global lock for all the cases is not good.

Fix this problem by protecting all md_thread with rcu.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230523021017.3048783-6-yukuai1@huaweicloud.com
2023-06-13 15:25:39 -07:00
Alexander Aring
12cda13cfd fs: dlm: remove DLM_LSFL_FS from uapi
The DLM_LSFL_FS flag is set in lockspaces created directly
for a kernel user, as opposed to those lockspaces created
for user space applications.  The user space libdlm allowed
this flag to be set for lockspaces created from user space,
but then used by a kernel user.  No kernel user has ever
used this method, so remove the ability to do it.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2022-08-23 14:54:54 -05:00
Zhang Jiaming
9e26728b5f md: Fix spelling mistake in comments
There are 2 spelling mistakes in comments. Fix it.

Signed-off-by: Zhang Jiaming <jiaming@nfschina.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02 17:14:44 -06:00
Heming Zhao
92d9aac92b md: replace deprecated strlcpy & remove duplicated line
This commit includes two topics:

1> replace deprecated strlcpy

change strlcpy to strscpy for strlcpy is marked as deprecated in
Documentation/process/deprecated.rst

2> remove duplicated strlcpy line

in md_bitmap_read_sb@md-bitmap.c there are two duplicated strlcpy(), the
history:

- commit cf921cc19c ("Add node recovery callbacks") introduced the first
  usage of strlcpy().

- commit b97e92574c ("Use separate bitmaps for each nodes in the cluster")
  introduced the second strlcpy(). this time, the two strlcpy() are same,
   we can remove anyone safely.

- commit d3b178adb3 ("md: Skip cluster setup for dm-raid") added dm-raid
  special handling. And the "nodes" value is the key of this patch. but
  from this patch, strlcpy() which was introduced by b97e92574c
  become necessary.

- commit 3c462c880b ("md: Increment version for clustered bitmaps") used
  clustered major version to only handle in clustered env. this patch
  could look a polishment for clustered code logic.

So cf921cc19c became useless after d3b178adb3, we could remove it
safely.

Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Song Liu <song@kernel.org>
2022-04-25 14:00:36 -07:00
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
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
Zhao Heming
bca5b06580 md/cluster: fix deadlock when node is doing resync job
md-cluster uses MD_CLUSTER_SEND_LOCK to make node can exclusively send msg.
During sending msg, node can concurrently receive msg from another node.
When node does resync job, grab token_lockres:EX may trigger a deadlock:
```
nodeA                       nodeB
--------------------     --------------------
a.
send METADATA_UPDATED
held token_lockres:EX
                         b.
                         md_do_sync
                          resync_info_update
                            send RESYNCING
                             + set MD_CLUSTER_SEND_LOCK
                             + wait for holding token_lockres:EX

                         c.
                         mdadm /dev/md0 --remove /dev/sdg
                          + held reconfig_mutex
                          + send REMOVE
                             + wait_event(MD_CLUSTER_SEND_LOCK)

                         d.
                         recv_daemon //METADATA_UPDATED from A
                          process_metadata_update
                           + (mddev_trylock(mddev) ||
                              MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD)
                             //this time, both return false forever
```
Explaination:
a. A send METADATA_UPDATED
   This will block another node to send msg

b. B does sync jobs, which will send RESYNCING at intervals.
   This will be block for holding token_lockres:EX lock.

c. B do "mdadm --remove", which will send REMOVE.
   This will be blocked by step <b>: MD_CLUSTER_SEND_LOCK is 1.

d. B recv METADATA_UPDATED msg, which send from A in step <a>.
   This will be blocked by step <c>: holding mddev lock, it makes
   wait_event can't hold mddev lock. (btw,
   MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD keep ZERO in this scenario.)

There is a similar deadlock in commit 0ba959774e
("md-cluster: use sync way to handle METADATA_UPDATED msg")
In that commit, step c is "update sb". This patch step c is
"mdadm --remove".

For fixing this issue, we can refer the solution of function:
metadata_update_start. Which does the same grab lock_token action.
lock_comm can use the same steps to avoid deadlock. By moving
MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD from lock_token to lock_comm.
It enlarge a little bit window of MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
but it is safe & can break deadlock.

Repro steps (I only triggered 3 times with hundreds tests):

two nodes share 3 iSCSI luns: sdg/sdh/sdi. Each lun size is 1GB.
```
ssh root@node2 "mdadm -S --scan"
mdadm -S --scan
for i in {g,h,i};do dd if=/dev/zero of=/dev/sd$i oflag=direct bs=1M \
count=20; done

mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sdg /dev/sdh \
 --bitmap-chunk=1M
ssh root@node2 "mdadm -A /dev/md0 /dev/sdg /dev/sdh"

sleep 5

mkfs.xfs /dev/md0
mdadm --manage --add /dev/md0 /dev/sdi
mdadm --wait /dev/md0
mdadm --grow --raid-devices=3 /dev/md0

mdadm /dev/md0 --fail /dev/sdg
mdadm /dev/md0 --remove /dev/sdg
mdadm --grow --raid-devices=2 /dev/md0
```

test script will hung when executing "mdadm --remove".

```
 # dump stacks by "echo t > /proc/sysrq-trigger"
md0_cluster_rec D    0  5329      2 0x80004000
Call Trace:
 __schedule+0x1f6/0x560
 ? _cond_resched+0x2d/0x40
 ? schedule+0x4a/0xb0
 ? process_metadata_update.isra.0+0xdb/0x140 [md_cluster]
 ? wait_woken+0x80/0x80
 ? process_recvd_msg+0x113/0x1d0 [md_cluster]
 ? recv_daemon+0x9e/0x120 [md_cluster]
 ? md_thread+0x94/0x160 [md_mod]
 ? wait_woken+0x80/0x80
 ? md_congested+0x30/0x30 [md_mod]
 ? kthread+0x115/0x140
 ? __kthread_bind_mask+0x60/0x60
 ? ret_from_fork+0x1f/0x40

mdadm           D    0  5423      1 0x00004004
Call Trace:
 __schedule+0x1f6/0x560
 ? __schedule+0x1fe/0x560
 ? schedule+0x4a/0xb0
 ? lock_comm.isra.0+0x7b/0xb0 [md_cluster]
 ? wait_woken+0x80/0x80
 ? remove_disk+0x4f/0x90 [md_cluster]
 ? hot_remove_disk+0xb1/0x1b0 [md_mod]
 ? md_ioctl+0x50c/0xba0 [md_mod]
 ? wait_woken+0x80/0x80
 ? blkdev_ioctl+0xa2/0x2a0
 ? block_ioctl+0x39/0x40
 ? ksys_ioctl+0x82/0xc0
 ? __x64_sys_ioctl+0x16/0x20
 ? do_syscall_64+0x5f/0x150
 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9

md0_resync      D    0  5425      2 0x80004000
Call Trace:
 __schedule+0x1f6/0x560
 ? schedule+0x4a/0xb0
 ? dlm_lock_sync+0xa1/0xd0 [md_cluster]
 ? wait_woken+0x80/0x80
 ? lock_token+0x2d/0x90 [md_cluster]
 ? resync_info_update+0x95/0x100 [md_cluster]
 ? raid1_sync_request+0x7d3/0xa40 [raid1]
 ? md_do_sync.cold+0x737/0xc8f [md_mod]
 ? md_thread+0x94/0x160 [md_mod]
 ? md_congested+0x30/0x30 [md_mod]
 ? kthread+0x115/0x140
 ? __kthread_bind_mask+0x60/0x60
 ? ret_from_fork+0x1f/0x40
```

At last, thanks for Xiao's solution.

Cc: stable@vger.kernel.org
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Suggested-by: Xiao Ni <xni@redhat.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-11-30 10:12:35 -08:00
Christoph Hellwig
94d91e7f8c md: remove a spurious call to revalidate_disk_size in update_size
None of the ->resize methods updates the disk size, so calling
revalidate_disk_size here won't do anything.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-11-16 08:34:15 -07:00
Christoph Hellwig
2c247c5169 md: use set_capacity_and_notify
Use set_capacity_and_notify to set the size of both the disk and block
device.  This also gets the uevent notifications for the resize for free.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-11-16 08:34:15 -07:00
Zhao Heming
1383b347a8 md/bitmap: fix memory leak of temporary bitmap
Callers of get_bitmap_from_slot() are responsible to free the bitmap.

Suggested-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-10-08 22:37:39 -07:00
Christoph Hellwig
659e56ba86 block: add a new revalidate_disk_size helper
revalidate_disk is a relative awkward helper for driver use, as it first
calls an optional driver method and then updates the block device size,
while most callers either don't need the method call at all, or want to
keep state between the caller and the called method.

Add a revalidate_disk_size helper that just performs the update of the
block device size from the gendisk one, and switch all drivers that do
not implement ->revalidate_disk to use the new helper instead of
revalidate_disk()

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-02 08:00:07 -06:00
Dan Carpenter
e8abe1de43 md-cluster: Fix potential error pointer dereference in resize_bitmaps()
The error handling calls md_bitmap_free(bitmap) which checks for NULL
but will Oops if we pass an error pointer.  Let's set "bitmap" to NULL
on this error path.

Fixes: afd7562860 ("md-cluster/raid10: resize all the bitmaps before start reshape")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-08-05 17:07:48 -07:00
Zhao Heming
60f80d6f2d md-cluster: fix wild pointer of unlock_all_bitmaps()
reproduction steps:
```
node1 # mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda
/dev/sdb
node2 # mdadm -A /dev/md0 /dev/sda /dev/sdb
node1 # mdadm -G /dev/md0 -b none
mdadm: failed to remove clustered bitmap.
node1 # mdadm -S --scan
^C  <==== mdadm hung & kernel crash
```

kernel stack:
```
[  335.230657] general protection fault: 0000 [#1] SMP NOPTI
[...]
[  335.230848] Call Trace:
[  335.230873]  ? unlock_all_bitmaps+0x5/0x70 [md_cluster]
[  335.230886]  unlock_all_bitmaps+0x3d/0x70 [md_cluster]
[  335.230899]  leave+0x10f/0x190 [md_cluster]
[  335.230932]  ? md_super_wait+0x93/0xa0 [md_mod]
[  335.230947]  ? leave+0x5/0x190 [md_cluster]
[  335.230973]  md_cluster_stop+0x1a/0x30 [md_mod]
[  335.230999]  md_bitmap_free+0x142/0x150 [md_mod]
[  335.231013]  ? _cond_resched+0x15/0x40
[  335.231025]  ? mutex_lock+0xe/0x30
[  335.231056]  __md_stop+0x1c/0xa0 [md_mod]
[  335.231083]  do_md_stop+0x160/0x580 [md_mod]
[  335.231119]  ? 0xffffffffc05fb078
[  335.231148]  md_ioctl+0xa04/0x1930 [md_mod]
[  335.231165]  ? filename_lookup+0xf2/0x190
[  335.231179]  blkdev_ioctl+0x93c/0xa10
[  335.231205]  ? _cond_resched+0x15/0x40
[  335.231214]  ? __check_object_size+0xd4/0x1a0
[  335.231224]  block_ioctl+0x39/0x40
[  335.231243]  do_vfs_ioctl+0xa0/0x680
[  335.231253]  ksys_ioctl+0x70/0x80
[  335.231261]  __x64_sys_ioctl+0x16/0x20
[  335.231271]  do_syscall_64+0x65/0x1f0
[  335.231278]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
```

Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-07-14 23:38:32 -07:00
Thomas Gleixner
8d7c56d08f treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 45
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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 11 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.370933192@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:12 +02:00
Guoqing Jiang
ea89238c0a md-cluster: remove suspend_info
Previously, we allow multiple nodes can resync device, but we
had changed it to only support one node can do resync at one
time, but suspend_info is still used.

Now, let's remove the structure and use suspend_lo/hi to record
the range.

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 09:41:25 -07:00
Guoqing Jiang
cb9ee15431 md-cluster: send BITMAP_NEEDS_SYNC message if reshaping is interrupted
We need to continue the reshaping if it was interrupted in
original node. So original node should call resync_bitmap
in case reshaping is aborted.

Then BITMAP_NEEDS_SYNC message is broadcasted to other nodes,
node which continues the reshaping should restart reshape from
mddev->reshape_position instead of from the first beginning.

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 09:40:48 -07:00
Guoqing Jiang
cbce6863b6 md-cluster/bitmap: don't call md_bitmap_sync_with_cluster during reshaping stage
When reshape is happening in one node, other nodes could receive
lots of RESYNCING messages, so md_bitmap_sync_with_cluster is called.

Since the resyncing window is typically small in these RESYNCING
messages, so WARN is always triggered, so we should not call the
func when reshape is happening.

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 09:40:01 -07:00
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
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
Guoqing Jiang
41a9504112 md-cluster: release RESYNC lock after the last resync message
All the RESYNC messages are sent with resync lock held, the only
exception is resync_finish which releases resync_lockres before
send the last resync message, this should be changed as well.
Otherwise, we can see deadlock issue as follows:

clustermd2-gqjiang2:~ # cat /proc/mdstat
Personalities : [raid10] [raid1]
md0 : active raid1 sdg[0] sdf[1]
      134144 blocks super 1.2 [2/2] [UU]
      [===================>.]  resync = 99.6% (134144/134144) finish=0.0min speed=26K/sec
      bitmap: 1/1 pages [4KB], 65536KB chunk

unused devices: <none>
clustermd2-gqjiang2:~ # ps aux|grep md|grep D
root     20497  0.0  0.0      0     0 ?        D    16:00   0:00 [md0_raid1]
clustermd2-gqjiang2:~ # cat /proc/20497/stack
[<ffffffffc05ff51e>] dlm_lock_sync+0x8e/0xc0 [md_cluster]
[<ffffffffc05ff7e8>] __sendmsg+0x98/0x130 [md_cluster]
[<ffffffffc05ff900>] sendmsg+0x20/0x30 [md_cluster]
[<ffffffffc05ffc35>] resync_info_update+0xb5/0xc0 [md_cluster]
[<ffffffffc0593e84>] md_reap_sync_thread+0x134/0x170 [md_mod]
[<ffffffffc059514c>] md_check_recovery+0x28c/0x510 [md_mod]
[<ffffffffc060c882>] raid1d+0x42/0x800 [raid1]
[<ffffffffc058ab61>] md_thread+0x121/0x150 [md_mod]
[<ffffffff9a0a5b3f>] kthread+0xff/0x140
[<ffffffff9a800235>] ret_from_fork+0x35/0x40
[<ffffffffffffffff>] 0xffffffffffffffff

clustermd-gqjiang1:~ # ps aux|grep md|grep D
root     20531  0.0  0.0      0     0 ?        D    16:00   0:00 [md0_raid1]
root     20537  0.0  0.0      0     0 ?        D    16:00   0:00 [md0_cluster_rec]
root     20676  0.0  0.0      0     0 ?        D    16:01   0:00 [md0_resync]
clustermd-gqjiang1:~ # cat /proc/mdstat
Personalities : [raid10] [raid1]
md0 : active raid1 sdf[1] sdg[0]
      134144 blocks super 1.2 [2/2] [UU]
      [===================>.]  resync = 97.3% (131072/134144) finish=8076.8min speed=0K/sec
      bitmap: 1/1 pages [4KB], 65536KB chunk

unused devices: <none>
clustermd-gqjiang1:~ # cat /proc/20531/stack
[<ffffffffc080974d>] metadata_update_start+0xcd/0xd0 [md_cluster]
[<ffffffffc079c897>] md_update_sb.part.61+0x97/0x820 [md_mod]
[<ffffffffc079f15b>] md_check_recovery+0x29b/0x510 [md_mod]
[<ffffffffc0816882>] raid1d+0x42/0x800 [raid1]
[<ffffffffc0794b61>] md_thread+0x121/0x150 [md_mod]
[<ffffffff9e0a5b3f>] kthread+0xff/0x140
[<ffffffff9e800235>] ret_from_fork+0x35/0x40
[<ffffffffffffffff>] 0xffffffffffffffff
clustermd-gqjiang1:~ # cat /proc/20537/stack
[<ffffffffc0813222>] freeze_array+0xf2/0x140 [raid1]
[<ffffffffc080a56e>] recv_daemon+0x41e/0x580 [md_cluster]
[<ffffffffc0794b61>] md_thread+0x121/0x150 [md_mod]
[<ffffffff9e0a5b3f>] kthread+0xff/0x140
[<ffffffff9e800235>] ret_from_fork+0x35/0x40
[<ffffffffffffffff>] 0xffffffffffffffff
clustermd-gqjiang1:~ # cat /proc/20676/stack
[<ffffffffc080951e>] dlm_lock_sync+0x8e/0xc0 [md_cluster]
[<ffffffffc080957f>] lock_token+0x2f/0xa0 [md_cluster]
[<ffffffffc0809622>] lock_comm+0x32/0x90 [md_cluster]
[<ffffffffc08098f5>] sendmsg+0x15/0x30 [md_cluster]
[<ffffffffc0809c0a>] resync_info_update+0x8a/0xc0 [md_cluster]
[<ffffffffc08130ba>] raid1_sync_request+0xa9a/0xb10 [raid1]
[<ffffffffc079b8ea>] md_do_sync+0xbaa/0xf90 [md_mod]
[<ffffffffc0794b61>] md_thread+0x121/0x150 [md_mod]
[<ffffffff9e0a5b3f>] kthread+0xff/0x140
[<ffffffff9e800235>] ret_from_fork+0x35/0x40
[<ffffffffffffffff>] 0xffffffffffffffff

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-08-31 17:38:10 -07:00
Linus Torvalds
08b5fa8199 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:

 - a new driver for Rohm BU21029 touch controller

 - new bitmap APIs: bitmap_alloc, bitmap_zalloc and bitmap_free

 - updates to Atmel, eeti. pxrc and iforce drivers

 - assorted driver cleanups and fixes.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (57 commits)
  MAINTAINERS: Add PhoenixRC Flight Controller Adapter
  Input: do not use WARN() in input_alloc_absinfo()
  Input: mark expected switch fall-throughs
  Input: raydium_i2c_ts - use true and false for boolean values
  Input: evdev - switch to bitmap API
  Input: gpio-keys - switch to bitmap_zalloc()
  Input: elan_i2c_smbus - cast sizeof to int for comparison
  bitmap: Add bitmap_alloc(), bitmap_zalloc() and bitmap_free()
  md: Avoid namespace collision with bitmap API
  dm: Avoid namespace collision with bitmap API
  Input: pm8941-pwrkey - add resin entry
  Input: pm8941-pwrkey - abstract register offsets and event code
  Input: iforce - reorganize joystick configuration lists
  Input: atmel_mxt_ts - move completion to after config crc is updated
  Input: atmel_mxt_ts - don't report zero pressure from T9
  Input: atmel_mxt_ts - zero terminate config firmware file
  Input: atmel_mxt_ts - refactor config update code to add context struct
  Input: atmel_mxt_ts - config CRC may start at T71
  Input: atmel_mxt_ts - remove unnecessary debug on ENOMEM
  Input: atmel_mxt_ts - remove duplicate setup of ABS_MT_PRESSURE
  ...
2018-08-18 16:48:07 -07:00
Andy Shevchenko
e64e4018d5 md: Avoid namespace collision with bitmap API
bitmap API (include/linux/bitmap.h) has 'bitmap' prefix for its methods.

On the other hand MD bitmap API is special case.
Adding 'md' prefix to it to avoid name space collision.

No functional changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Shaohua Li <shli@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2018-08-01 15:49:39 -07:00
Guoqing Jiang
df8c676418 md-cluster: don't send msg if array is closing
If we close an array which resync thread is running,
then we don't need the node to send msg since another
node would launch the resync thread to continue the
rest works. Also send a message is time consuming,
we should avoid it.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-07-05 11:17:02 -07:00
Guoqing Jiang
0357ba27bd md-cluster: show array's status more accurate
When resync or recovery is happening in one node,
other nodes don't show the appropriate info now.

For example, when create an array in master node
without "--assume-clean", then assemble the array
in slave nodes, you can see "resync=PENDING" when
read /proc/mdstat in slave nodes. However, the info
is confusing since "PENDING" status is introduced
for start array in read-only mode.

We introduce RESYNCING_REMOTE flag to indicate that
resync thread is running in remote node. The flags
is set when node receive RESYNCING msg. And we clear
the REMOTE flag in following cases:

1. resync or recover is finished in master node,
   which means slaves receive msg with both lo
   and hi are set to 0.
2. node continues resync/recovery in recover_bitmaps.
3. when resync_finish is called.

Then we show accurate information in status_resync
by check REMOTE flags and with other conditions.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-07-05 11:17:01 -07:00
Guoqing Jiang
010228e4a9 md-cluster: clear another node's suspend_area after the copy is finished
When one node leaves cluster or stops the resyncing
(resync or recovery) array, then other nodes need to
call recover_bitmaps to continue the unfinished task.

But we need to clear suspend_area later after other
nodes copy the resync information to their bitmap
(by call bitmap_copy_from_slot). Otherwise, all nodes
could write to the suspend_area even the suspend_area
is not handled by any node, because area_resyncing
returns 0 at the beginning of raid1_write_request.
Which means one node could write suspend_area while
another node is resyncing the same area, then data
could be inconsistent.

So let's clear suspend_area later to avoid above issue
with the protection of bm lock. Also it is straightforward
to clear suspend_area after nodes have copied the resync
info to bitmap.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-07-05 11:17:01 -07:00
Kees Cook
6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Guoqing Jiang
f0e230ad87 md-cluster: update document for raid10
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-01 21:32:25 -07:00
NeilBrown
b03e0ccb5a md: remove special meaning of ->quiesce(.., 2)
The '2' argument means "wake up anything that is waiting".
This is an inelegant part of the design and was added
to help support management of suspend_lo/suspend_hi setting.
Now that suspend_lo/hi is managed in mddev_suspend/resume,
that need is gone.
These is still a couple of places where we call 'quiesce'
with an argument of '2', but they can safely be changed to
call ->quiesce(.., 1); ->quiesce(.., 0) which
achieve the same result at the small cost of pausing IO
briefly.

This removes a small "optimization" from suspend_{hi,lo}_store,
but it isn't clear that optimization served a useful purpose.
The code now is a lot clearer.

Suggested-by: Shaohua Li <shli@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-01 21:32:20 -07:00
Mike Snitzer
935fe0983e md: rename some drivers/md/ files to have an "md-" prefix
Motivated by the desire to illiminate the imprecise nature of
DM-specific patches being unnecessarily sent to both the MD maintainer
and mailing-list.  Which is born out of the fact that DM files also
reside in drivers/md/

Now all MD-specific files in drivers/md/ start with either "raid" or
"md-" and the MAINTAINERS file has been updated accordingly.

Shaohua: don't change module name

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-10-16 19:06:36 -07:00
Colin Ian King
7a57157aeb md-cluster: make function cluster_check_sync_size static
The function cluster_check_sync_size is local to the source and does
not need to be in global scope, so make it static.

Cleans up sparse warning:
symbol 'cluster_check_sync_size' was not declared. Should it be static?

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-10-16 19:06:35 -07:00
Guoqing Jiang
2dffdc0724 md-cluster: fix potential lock issue in add_new_disk
The add_new_disk returns with communication locked if
__sendmsg returns failure, fix it with call unlock_comm
before return.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
CC: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-05-21 20:37:09 -07:00
Christophe JAILLET
835d89e92f md-cluster: Fix a memleak in an error handling path
We know that 'bm_lockres' is NULL here, so 'lockres_free(bm_lockres)' is a
no-op. According to resource handling in case of error a few lines below,
it is likely that 'bitmap_free(bitmap)' was expected instead.

Fixes: b98938d16a ("md-cluster: introduce cluster_check_sync_size")

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-04-14 08:08:29 -07:00
Guoqing Jiang
818da59f97 md-cluster: add the support for resize
To update size for cluster raid, we need to make
sure all nodes can perform the change successfully.
However, it is possible that some of them can't do
it due to failure (bitmap_resize could fail). So
we need to consider the issue before we set the
capacity unconditionally, and we use below steps
to perform sanity check.

1. A change the size, then broadcast METADATA_UPDATED
   msg.
2. B and C receive METADATA_UPDATED change the size
   excepts call set_capacity, sync_size is not update
   if the change failed. Also call bitmap_update_sb
   to sync sb to disk.
3. A checks other node's sync_size, if sync_size has
   been updated in all nodes, then send CHANGE_CAPACITY
   msg otherwise send msg to revert previous change.
4. B and C call set_capacity if receive CHANGE_CAPACITY
   msg, otherwise pers->resize will be called to restore
   the old value.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-16 16:55:50 -07:00
Guoqing Jiang
b98938d16a md-cluster: introduce cluster_check_sync_size
Support resize is a little complex for clustered
raid, since we need to ensure all the nodes share
the same knowledge about the size of raid.

We achieve the goal by check the sync_size which
is in each node's bitmap, we can only change the
capacity after cluster_check_sync_size returns 0.

Also, get_bitmap_from_slot is added to get a slot's
bitmap. And we exported some funcs since they are
used in cluster_check_sync_size().

We can also reuse get_bitmap_from_slot to remove
redundant code existed in bitmap_copy_from_slot.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-16 16:55:50 -07:00
Guoqing Jiang
7da3d20333 md-cluster: add CHANGE_CAPACITY message type
The msg type CHANGE_CAPACITY is introduced to support
resize clustered raid in later patch, and it is sent
after all the nodes have the same sync_size, receiver
node just need to set new capacity once received this
msg.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-16 16:55:49 -07:00
Guoqing Jiang
0ba959774e md-cluster: use sync way to handle METADATA_UPDATED msg
Previously, when node received METADATA_UPDATED msg, it just
need to wakeup mddev->thread, then md_reload_sb will be called
eventually.

We taken the asynchronous way to avoid a deadlock issue, the
deadlock issue could happen when one node is receiving the
METADATA_UPDATED msg (wants reconfig_mutex) and trying to run
the path:

md_check_recovery -> mddev_trylock(hold reconfig_mutex)
                  -> md_update_sb-metadata_update_start
		     (want EX on token however token is
		      got by the sending node)

Since we will support resizing for clustered raid, and we
need the metadata update handling to be synchronous so that
the initiating node can detect failure, so we need to change
the way for handling METADATA_UPDATED msg.

But, we obviously need to avoid above deadlock with the
sync way. To make this happen, we considered to not hold
reconfig_mutex to call md_reload_sb, if some other thread
has already taken reconfig_mutex and waiting for the 'token',
then process_recvd_msg() can safely call md_reload_sb()
without taking the mutex. This is because we can be certain
that no other thread will take the mutex, and we also certain
that the actions performed by md_reload_sb() won't interfere
with anything that the other thread is in the middle of.

To make this more concrete, we added a new cinfo->state bit
        MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD

Which is set in lock_token() just before dlm_lock_sync() is
called, and cleared just after. As lock_token() is always
called with reconfig_mutex() held (the specific case is the
resync_info_update which is distinguished well in previous
patch), if process_recvd_msg() finds that the new bit is set,
then the mutex must be held by some other thread, and it will
keep waiting.

So process_metadata_update() can call md_reload_sb() if either
mddev_trylock() succeeds, or if MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD
is set. The tricky bit is what to do if neither of these apply.
We need to wait. Fortunately mddev_unlock() always calls wake_up()
on mddev->thread->wqueue. So we can get lock_token() to call
wake_up() on that when it sets the bit.

There are also some related changes inside this commit:
1. remove RELOAD_SB related codes since there are not valid anymore.
2. mddev is added into md_cluster_info then we can get mddev inside
   lock_token.
3. add new parameter for lock_token to distinguish reconfig_mutex
   is held or not.

And, we need to set MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD in below:
1. set it before unregister thread, otherwise a deadlock could
   appear if stop a resyncing array.
   This is because md_unregister_thread(&cinfo->recv_thread) is
   blocked by recv_daemon -> process_recvd_msg
			  -> process_metadata_update.
   To resolve the issue, MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD is
   also need to be set before unregister thread.
2. set it in metadata_update_start to fix another deadlock.
	a. Node A sends METADATA_UPDATED msg (held Token lock).
	b. Node B wants to do resync, and is blocked since it can't
	   get Token lock, but MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD is
	   not set since the callchain
	   (md_do_sync -> sync_request
        	       -> resync_info_update
		       -> sendmsg
		       -> lock_comm -> lock_token)
	   doesn't hold reconfig_mutex.
	c. Node B trys to update sb (held reconfig_mutex), but stopped
	   at wait_event() in metadata_update_start since we have set
	   MD_CLUSTER_SEND_LOCK flag in lock_comm (step 2).
	d. Then Node B receives METADATA_UPDATED msg from A, of course
	   recv_daemon is blocked forever.
   Since metadata_update_start always calls lock_token with reconfig_mutex,
   we need to set MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD here as well, and
   lock_token don't need to set it twice unless lock_token is invoked from
   lock_comm.

Finally, thanks to Neil for his great idea and help!

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-16 16:55:49 -07:00
Guoqing Jiang
75df023f4f md-cluster: remove useless memset from gather_all_resync_info
This memset is not needed.  The lvb is already zeroed because
it was recently allocated by lockres_init, which uses kzalloc(),
and read_resync_info() doesn't need it to be zero anyway.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-09 09:02:06 -08:00
Guoqing Jiang
9c8043f337 md-cluster: free md_cluster_info if node leave cluster
To avoid memory leak, we need to free the cinfo which
is allocated when node join cluster.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-03-09 09:01:47 -08:00
Guoqing Jiang
d6385db941 md-cluster: make resync lock also could be interruptted
When one node is perform resync or recovery, other nodes
can't get resync lock and could block for a while before
it holds the lock, so we can't stop array immediately for
this scenario.

To make array could be stop quickly, we check MD_CLOSING
in dlm_lock_sync_interruptible to make us can interrupt
the lock request.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Guoqing Jiang
7bcda7149d md-cluster: introduce dlm_lock_sync_interruptible to fix tasks hang
When some node leaves cluster, then it's bitmap need to be
synced by another node, so "md*_recover" thread is triggered
for the purpose. However, with below steps. we can find tasks
hang happened either in B or C.

1. Node A create a resyncing cluster raid1, assemble it in
   other two nodes (B and C).
2. stop array in B and C.
3. stop array in A.

linux44:~ # ps aux|grep md|grep D
root	5938	0.0  0.1  19852  1964 pts/0    D+   14:52   0:00 mdadm -S md0
root	5939	0.0  0.0      0     0 ?        D    14:52   0:00 [md0_recover]

linux44:~ # cat /proc/5939/stack
[<ffffffffa04cf321>] dlm_lock_sync+0x71/0x90 [md_cluster]
[<ffffffffa04d0705>] recover_bitmaps+0x125/0x220 [md_cluster]
[<ffffffffa052105d>] md_thread+0x16d/0x180 [md_mod]
[<ffffffff8107ad94>] kthread+0xb4/0xc0
[<ffffffff8152a518>] ret_from_fork+0x58/0x90

linux44:~ # cat /proc/5938/stack
[<ffffffff8107afde>] kthread_stop+0x6e/0x120
[<ffffffffa0519da0>] md_unregister_thread+0x40/0x80 [md_mod]
[<ffffffffa04cfd20>] leave+0x70/0x120 [md_cluster]
[<ffffffffa0525e24>] md_cluster_stop+0x14/0x30 [md_mod]
[<ffffffffa05269ab>] bitmap_free+0x14b/0x150 [md_mod]
[<ffffffffa0523f3b>] do_md_stop+0x35b/0x5a0 [md_mod]
[<ffffffffa0524e83>] md_ioctl+0x873/0x1590 [md_mod]
[<ffffffff81288464>] blkdev_ioctl+0x214/0x7d0
[<ffffffff811dd3dd>] block_ioctl+0x3d/0x40
[<ffffffff811b92d4>] do_vfs_ioctl+0x2d4/0x4b0
[<ffffffff811b9538>] SyS_ioctl+0x88/0xa0
[<ffffffff8152a5c9>] system_call_fastpath+0x16/0x1b

The problem is caused by recover_bitmaps can't reliably abort
when the thread is unregistered. So dlm_lock_sync_interruptible
is introduced to detect the thread's situation to fix the problem.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Guoqing Jiang
fccb60a42c md-cluster: convert the completion to wait queue
Previously, we used completion to sync between require dlm lock
and sync_ast, however we will have to expose completion.wait
and completion.done in dlm_lock_sync_interruptible (introduced
later), it is not a common usage for completion, so convert
related things to wait queue.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Guoqing Jiang
5f0aa21da6 md-cluster: protect md_find_rdev_nr_rcu with rcu lock
We need to use rcu_read_lock/unlock to avoid potential
race.

Reported-by: Shaohua Li <shli@fb.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Guoqing Jiang
e3f924d3df md-cluster: remove some unnecessary dlm_unlock_sync
Since DLM_LKF_FORCEUNLOCK is used in lockres_free,
we don't need to call dlm_unlock_sync before free
lock resource.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Guoqing Jiang
400cb454a4 md-cluster: use FORCEUNLOCK in lockres_free
For dlm_unlock, we need to pass flag to dlm_unlock as the
third parameter instead of set res->flags.

Also, DLM_LKF_FORCEUNLOCK is more suitable for dlm_unlock
since it works even the lock is on waiting or convert queue.

Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Wei Yongjun
0f6187dbe5 md-cluster: fix error return code in join()
Fix to return error code -ENOMEM from the lockres_init() error
handling case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-08-24 10:21:51 -07:00
Guoqing Jiang
1fa9a1ad0a md-cluster: check the return value of process_recvd_msg
We don't need to run the full path of recv_daemon
if process_recvd_msg doesn't return 0.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-09 09:24:04 -07:00
Guoqing Jiang
51e453aecb md-cluster: gather resync infos and enable recv_thread after bitmap is ready
The in-memory bitmap is not ready when node joins cluster,
so it doesn't make sense to make gather_all_resync_info()
called so earlier, we need to call it after the node's
bitmap is setup. Also, recv_thread could be wake up after
node joins cluster, but it could cause problem if node
receives RESYNCING message without persionality since
mddev->pers->quiesce is called in process_suspend_info.

This commit introduces a new cluster interface load_bitmaps
to fix above problems, load_bitmaps is called in bitmap_load
where bitmap and persionality are ready, and load_bitmaps
does the following tasks:

1. call gather_all_resync_info to load all the node's
   bitmap info.
2. set MD_CLUSTER_ALREADY_IN_CLUSTER bit to recv_thread
   could be wake up, and wake up recv_thread if there is
   pending recv event.

Then ack_bast only wakes up recv_thread after IN_CLUSTER
bit is ready otherwise MD_CLUSTER_PENDING_RESYNC_EVENT is
set.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-09 09:24:03 -07:00
Guoqing Jiang
18c9ff7f48 md-cluster: sync bitmap when node received RESYNCING msg
If the node received RESYNCING message which means
another node will perform resync with the area, then
we don't want to do it again in another node.

Let's set RESYNC_MASK and clear NEEDED_MASK for the
region from old-low to new-low which has finished
syncing, and the region from old-hi to new-hi is about
to syncing, bitmap_sync_with_cluste is introduced 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>
2016-05-04 12:39:35 -07:00
Guoqing Jiang
1535212c54 md-cluster: fix locking when node joins cluster during message broadcast
If a node joins the cluster while a message broadcast
is under way, a lock issue could happen as follows.

For a cluster which included two nodes, if node A is
calling __sendmsg before up-convert CR to EX on ack,
and node B released CR on ack. But if a new node C
joins the cluster and it doesn't receive the message
which A sent before, so it could hold CR on ack before
A up-convert CR to EX on ack.

So a node joining the cluster should get an EX lock on
the "token" first to ensure no broadcast is ongoing,
then release it after held CR on ack.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-04 12:39:35 -07:00